Oxygen is vital for life. Redox stress is important in cell signal transduction, mediating many physiological and pathological processes such as aging, neurodegenerative diseases, metabolic diseases and tumors. Redox homeostasis maintainance is critical for promoting life health. In this paper, the lasting challenges during antioxidant research and development and the beyond main reasons were analyzed: including insufficient understanding of the physiological function of redox stress; excessive antioxidant, causing reductive stress; antioxidant strategies lacking specificity. Here the author proposed that cells and the body own precise redox nature, therefore, redox intervention strategies such as anti-oxidation should consider the "5R" principle, i.e. right species, right time, right place, right level, right target. Precision redox regulation is the future direction and precise redox medicine development is opening.

Ferroptosis is a novel type of cell death, which is distinguished from the traditional cell death pathways such as apoptosis, proptosis, necrosis and autophagy in terms of morphology, biochemistry and genetics. The main features of ferroptosis are the iron accumulation and lipid peroxidation. The regulation mechanism of ferroptosis involves glutathione metabolism, lipid peroxidation reactions and iron metabolism, which are closely related to the pathological process of tumor, aging, neurodegenerative diseases, ischemia reperfusion injury, cardiovascular and cerebrovascular diseases, kidney injury, hepatic fibrosis and so on. How to effectively study the role of ferroptosis regulation mechanism in the treatment of diseases becomes the hot spot and focus of the ferroptosis research. In recent years, with the in-depth study of ferroptosis, the identification, confirmation and the mechanism of ferroptosis have been developed significantly and have come forth continuously, in the meantime, techniques based on the morphology, biochemistry, molecular biology and genetics have been widely applied in the detection of ferroptosis. In order to deepen readers' understanding of ferroptosis and its detection methods, this paper will mainly review the current research progress on the detection methods and their application in ferroptosis, summarize and discuss their advantages and disadvantages in the detection of ferroptosis, this knowledge are crucial for better understanding and studying the biological function of ferroptosis.

The remodeling of phospholipid includes two processes: deacylation and reacylation. It realizes the conversion of nascent phospholipids to mature phospholipids by changing the length and types of fatty acids at specific sites of phospholipids, which is a key step in phospholipid metabolism. Phospholipids are not only the basic components of biological membranes, but also participate in the transduction of many molecular signals in cells. Therefore, phospholipid remodeling disorders can affect the structure and function of cell membranes, as well as the activity of membrane proteins, causing a series of intricate signaling cascades, and finally lead to many pathological changes including neurodegeneration. This paper reviews the basic process of phospholipid remodeling and the involvement of its key enzymes, calcium independent group VIA phospholipase A₂ (iPLA₂β), peroxiredoxin 6 (PRDX6), calcium independent group VIB phospholipase A₂ (iPLA₂γ) as well as acyl-CoA lysocardiolipin acyltransferase 1 (ALCAT1) in the pathology of Parkinson's disease. The mutations in the gene encoding iPLA₂β, PLA2G6, have been widely reported to be directly related to hereditary Parkinson disease-14 (PARK14). Here we focus on the molecular mechanism of iPLA₂β in the development of Parkinson's disease, mainly involving phospholipid fatty acid metabolism disorders, mitochondrial physiology abnormalities and α-synuclein aggregate formation and other aspects, which will help to understand the role of phospholipid remodeling in Parkinson's disease, and provide new clues for the development of new Parkinson's disease diagnosis and treatment strategies.

Immune checkpoints (ICs) are immunosuppressive molecules expressed on immune cells, which can regulate immune cells' activation. Immune checkpoint inhibitors (ICIs) which can block the interaction of immune checkpoints and their ligands, improve the cytotoxic effect of the immune system on tumor cells. Immunotherapy such as employing ICIs has gradually become a conventional therapeutic strategy for cancer treatment. However, the low response rate and the emergence of drug resistance have seriously affected the clinical efficacy of ICIs. Reactive oxygen species (ROS) are electronic reduction products of active oxygen, as well as natural by-products of cell metabolism, which can be used as regulators of intercellular signals. Tumor microenvironment (TME) is often in the state of oxidative stress (OS), which is the imbalance between oxidative system and antioxidant system. ROS can affect the interaction with its ligands by regulating the expression and activity of immune checkpoints in TME, thus affecting the anti-tumor effect of immune cells. Accumulating studies have shown that ROS could regulate tumor immune checkpoints through several pathways. Due to different types and stages of tumor, it would be clinical beneficial to understand the mechanistic link of ROS on tumor immune checkpoint, and choose appropriate ROS regulators combined with immune checkpoint inhibitors to maximize anti-tumor effects. This article reviews the common metabolic sources and characteristics of ROS, the regulatory effect and mechanism of ROS on tumor immune checkpoints and its therapeutic application.

Heme oxygenase-1 (HO-1) is a cytoprotective enzyme that catalyzes the conversion of heme to CO, biliverdin, and iron, which together protect cells from oxidative and inflammatory damage and play an important role in maintaining cell homeostasis. In recent years, HO-1 has also been found to have antiviral biological effects, and the induced expression of HO-1 inhibits the replication of various viruses such as hepatitis C virus, hepatitis B virus, human immunodeficiency virus, dengue virus, ebolavirus, influenza A virus, Zika virus, severe acute respiratory syndrome coronavirus 2, human respiratory syncytial virus, hepatitis A virus and enterovirus 71. The inhibitory effect of HO-1 on these viruses involves three mechanisms, including direct inhibition of virus replication by HO-1 and its downstream products, enhancement of type I interferon responses in host cell, and attenuation of inflammatory damage caused by viral infection. This review focuses on the recent advances in the antiviral effect of HO-1 and its mechanism, which is expected to provide evidence for HO-1 as a potential target for antiviral therapy.

The pathogenesis of heart failure is a complex progression and associated with abnormal regulation of many signaling pathways. As a cofactor of hemoglobin, myoglobin, oxidative respiratory chain, DNA synthase and other important proteins, iron plays an indispensable role in myocardial energy metabolism. Recently, a large number of studies have shown that heart failure is related to the disorder of iron metabolism. Both iron deficiency and iron overload can lead to the development of a variety of cardiomyopathy, and even progress to heart failure. Iron metabolism could be a key target for the diagnosis, prevention and treatment of heart failure. Here, we review the basic process of iron metabolism and its mechanism in heart failure, expecting to provide new clues and evidence for the treatment of heart failure.

The iron and inflammation homeostasis are closely coupled, forming an integrated functional unit under physiological conditions. "Iron transport balance" has become the key mechanism to maintain iron homeostasis through bidirectional regulation of iron uptake and release and dynamic management of transmembrane concentration. It is also the physiological basis for the inflammatory balance between promotion and resolution. Under pathological conditions, represented by inflammatory bowel disease (IBD), disturbed iron transportation was highly involved in almost every step of inflammatory diseases. Therefore, the iron transporting rebalancing provides the mechanistic basis and effective approach for the normalization of inflammatory microenvironment. Macrophage is the key regulator of inflammation homeostasis and determinant for iron transport balance. Unfortunately, the current clinical transformation based on iron transport balance theory has still been insufficient. Sometimes, this strategy even showed high complexity and contradiction, severely restricting its clinical application. By summarizing the theoretical research progress of iron transport balance, especially its relevance to macrophage phenotypic polarization, this review aims to explore the therapeutic value in inflammation intervention by targeting iron transporting balance. This review will provide the necessary knowledge and hints for the research and development of candidate drugs in treating inflammatory diseases.

The discovery of regulatory cell death has led to new breakthroughs in the field of disease treatment. As a novel discovered regulatory cell death in the past decade, ferroptosis is characterized by abnormal increase of intracellular iron ions and peroxidative damage of cell membrane lipids, morphological features of mitochondrial volume reduction, increased mitochondrial membrane density, as well as mitochondria decrease or disappear. The mechanism of ferroptosis is mainly associated with factors such as iron metabolism disorder, lipid metabolism abnormality, amino acid antioxidant system imbalance and oxidative stress. Since the liver is the main organ of human body for storing iron ions, it is necessary to deeply investigate the mechanism of ferroptosis in liver diseases. Relevant studies have shown that ferroptosis plays different roles in various liver diseases and is closely related to the process of liver diseases, including drug-induced liver injury, alcoholic fatty liver disease, non-alcoholic fatty liver diseases, viral hepatitis, liver fibrosis and hepatocellular carcinoma. The aim of this review is to link ferroptosis and liver diseases, concentrating on the iron metabolism disorder, accumulation of lipid peroxides in cell membranes, imbalance of amino acid antioxidant system, hyperpolarization of mitochondrial membrane potential and its accumulation of lipid peroxides, oxidative stress-related transcription factors and other aspects. This review summarizes the regulatory mechanism, current situation and the roles of ferroptosis in liver diseases, in order to provide a new theoretical basis and ideas for the in-depth study of ferroptosis and the treatment of liver diseases.

Ferroptosis is a novel cell death mode proposed in recent years, which is characterized by intracellular iron-dependent lipid peroxidation. Its mechanisms include lipid peroxidation, iron accumulation and the imbalance of antioxidant system. The crosstalk between ferroptosis and asthma is gradually deepening. Elucidating the specific mechanism of ferroptosis in regulating asthma is helpful to broaden the understanding of the pathology of asthma. This paper expounds the role of ferroptosis in airway epithelial cells in the occurrence and development of asthma from three perspectives: lipid peroxidation, iron accumulation and the imbalance of antioxidant system, hoping to find new targets and strategies for asthma treatment.

Cystine/glutamate antiporter [system Xc(-)] is a sodium independent amino acid transporter, which is a heterodimer composed of light chain subunit xCT and heavy chain subunit 4F2hc (CD98) through covalent disulfide bond. System Xc(-) typically mediates cystine uptake and glutamate output, helps to maintain the balance of glutamate, cystine and cysteine inside and outside the cell, regulates the level of glutamate inside and outside the membrane and the synthesis of intracellular glutathione, thus affecting oxidative stress and glutamate neurotoxicity. This review expounds the structure and function of system Xc(-), analyzes the role of the transporter in physiology and pathology, discusses the role and mechanism in different diseases, and discusses the specific research progress of system Xc(-) as a drug target. This review summarizes the research status of system Xc(-) and provides theoretical guidance for further research on system Xc(-) and drug discovery.

Mitochondrial oxidative stress has been recognized as a preliminary and critical factor that aggravates the pathological cascade of Alzheimer's disease, which induces the production of β-amyloid protein, upregulates the expression of phosphorylated tau protein and triggers oxidative damage to lipids, proteins and mitochondrial deoxyribonucleic acid. Central neurons are more vulnerable to oxidative stress than non-neuronal cells due to their high oxygen demand, abundant unsaturated fatty acids and antioxidant enzymes deficiency. On this account, this review introduces the causes of mitochondrial oxidative stress, and analyzes the important role of mitochondrial oxidative stress in the pathogenesis of Alzheimer's disease. Meanwhile, the review focuses on the design and intervention strategies of drug delivery systems targeting mitochondrial oxidative stress in neurons, aiming to provide new ideas for the prevention and treatment of Alzheimer's disease.

In this study, according to TCM theory of "liver qi stagnation forming fire", emotional stress mice model was employed to evaluate the protective effects of Qingre Xiaoyanning on herpes simplex virus type 1 (HSV-1) induced reactivation. The animal experimental protocol has been reviewed and approved by Laboratory Animal Ethics Committee of Jinan University, in compliance with the Institutional Animal Care Guidelines. BALB/c mice were divided into six groups, including mock group, HSV-1 latency group, HSV-1 reactivation group (HSV-1 latency + stress), low (0.658 g·kg^-1·day^-1) and high dose (1.316 g·kg^-1·day^-1) of Qingre Xiaoyanning groups and positive control group (acyclovir, 0.206 g·kg^-1·day^-1). Except for the normal group and HSV-1 latency group, all mice in other groups received a daily 12-h restraint stress for 4 days. After 7-day treatment of drugs, body weight and recurrent eye infections of mice were recorded. Brain tissues were harvested to monitor HSV-1 antigen distribution by immunohistochemical staining and detect virus titer by plaque assay. In the meantime, the mRNA and protein levels of infected cell polypeptide (ICP27) and glycoprotein B (gB) in the brain tissues were detected by RT-PCR and Western blot, respectively. The level of 4-hydroxynonenal (4-HNE) and expressions of ferroptosis-related proteins were measured by Western blot. The evaluation of malondialdehyde (MDA) content in the brain tissues was conducted by MDA assay commercial kit. The results showed that Qingre Xiaoyanning significantly retarded the decline of body weight of mice induced by HSV-1 reactivation, reduced the activation rate of HSV-1 and recurrent eye infections, declined virus titer of HSV-1, down-regulated gene and protein expressions of ICP27 and gB, and hindered the distribution of HSV-1 antigen in the brain of mice. Meanwhile, Qingre Xiaoyanning also decreased the protein expression of ferroptosis-related proteins, including DMT1, TFR1 and ALOX15 in the brain tissue of HSV-1 reactivated mice. The levels of lipid peroxidation products, 4-HNE and MDA, were also reduced by Qingre Xiaoyanning treatment. All the above results indicate that Qingre Xiaoyanning significantly inhibited HSV-1 reactivation by restraint stress, which might be related to the regulation of ferroptosis. Our findings provide a theoretical basis for the application of "clearing liver-fire" TCM on treatmenting HSV-1 reactivation-related symptoms.

In this study, chronic emotional stress-induced H1N1 influenza susceptibility model was employed to simulate the states of "emotional stagnation" and "liver fire invading lung", and the protective effect of Qinggan Xiefei Fang on viral pneumonia was investigated. Survival rate and morbidity rate of mice were observed within 21 days after H1N1 infection, the symptoms of viral pneumonia and the level of phospholipid peroxidation were detected in lungs of mice after 6-day infection. The experimental results showed that Qinggan Xiefei Fang could alleviate the decline of survival rate and morbidity rate of mice caused by chronic constraint stress loaded with H1N1, inhibit the replication of H1N1 and the production of inflammatory factors, reduce the level of phospholipid peroxidation, and improve the symptoms of pneumonia in mice. The results also showed that compound-target network of Qinggan Xiefei Fang contained 171 compounds and 260 corresponding targets involved in the signaling pathway of oxidative stress, inflammation and immunity. All the above results indicate that Qinggan Xiefei Fang protecting influenza virus pneumonia was related to the regulation of oxidative stress. The animal experimental protocol has been reviewed and approved by Laboratory Animal Ethics Committee of Jinan University, in compliance with the Institutional Animal Care Guidelines.

The abnormal lipids metabolism is a critical pathological feature of coronary heart disease (CHD). Additional supplemental intake of polyunsaturated fatty acid (PUFA) has long been considered to be an effective strategy for preventing CHD, but more and more clinical trials have denied this view. Still, it is ambiguity for the specific mechanism of PUFA in CHD. The experimental programs are compliant with ethical principles for animal use and have been approved by the Animal Experiment Ethics Committee of Jinan University. In the present study, we established an animal model by intake of omega-6 PUFA combined acute myocardial ischemia to explore the mechanism of CHD. Intragastric administration of linoleic acid (LA) for 14 days, intraperitoneal injection of isoprenaline (ISO) was applied to induce acute myocardial ischemia for the animal model establishment. The animal ultrasound imaging system was used to detect cardiac function in vivo after ISO injection for 24 h. Serum and heart tissue samples were collected for the myocardial enzyme, phospholipidomics analysis and molecular biological detection. Compared to the LA group, the cardiac function showed that the left ventricular ejection fraction (EF%) and the left ventricular shortening fraction (FS%) decreased, aspaetate aminotransferase (AST), creatine kinase isoenzyme (CK-MB), and lactate dehydrogenase (LDH) increased in the LA + ISO mice. Compared to the ISO group, the phospholipidomics analysis showed that the PUFAs significantly were raised in the LA + ISO myocardium, and the content of oxidized phosphatidylethanolamine (ox-PE) changed most remarkable. Compared with the ISO group, the molecular biology detection showed that glutathione (GSH) and nicotinamide adenine dinucleotide phosphate (NADPH) were depleted, the end-products of ox-PE were increased, and the level of arachidonic acid 12/15-lipoxygenase (ALOX15) protein expression increased obviously. We suggest that ALOX15 mediated phospholipid peroxidation might be the critical mechanism of LA increased the susceptibility of myocardial ischemia injury. This study provides an experimental basis for whether PUFA could be used as an alternative treatment strategy for CHD prevention and provides a new intervention target for the early prevention strategy of CHD.

The aim of this study is to investigate the role of fibroblast growth factor 21 (FGF21) in empagliflozin (EMP) in treatment of heart failure and the related mechanisms. FGF21 knockout (FGF21 KO) and littermate wild-type (WT) mice induced by doxorubicin (Dox) were used to establish heart failure mouse model in vivo. The experiment process and animal welfare follow the regulations of Animal Ethics Committee of Hefei University of Technology strictly. The results suggest that Dox (5 mg·kg^-1) induced typical heart failure symptoms in both WT and FGF21 KO mice. In WT mice, EMP (10 mg·kg^-1) significantly improved Dox-induced cardiac atrophy, decreased myocardial systolic function, decreased left ventricular ejection fraction and shortened fraction; EMP treatment also significantly inhibited the increase of Dox-induced cardiotoxicity indexes (aspartate amino transferase, creatine kinase, hydroxybutyrate dehydrogenase, lactate dehydrogenase) in mice. Dox induced cardiac fibrosis, inflammation and oxidative stress were also significantly improved by EMP. However, in FGF21 KO mice, the therapeutic effects of EMP on heart failure was significantly inhibited. The results suggest that the function of EMP in treating heart failure partly depends on the presence of FGF21, and the mechanism may be related to the effect of FGF21 on improving fibrosis, inflammation and oxidative stress.

The aim of this study was to establish an efficient and stable mouse model of hyperuricemic nephropathy (HN) by testing different modes of administration of potassium oxonate (PO) combined with hypoxanthine (Hx). Animal welfare and experimental procedures were in accordance with the regulations of the Animal Ethics Committee of Guangdong Pharmaceutical University. Male C57BL/6 mice were randomly divided into a control group, a PO+Hx group (i.g.; 100 mg·kg^-1·d^-1 and 500 mg·kg^-1·d^-1, respectively), and a PO+Hx group (i.p.; 100 mg·kg^-1·d^-1, and 500 mg·kg^-1·d^-1). This HN model was induced by combination of PO and Hx administration once daily for 21 days. The results of serum biochemistry showed that the levels of serum creatinine and 24 h albuminuria were increased compared with the normal group in intragastric administration of PO combined with Hx (P < 0.05), but there was no significant difference in serum uric acid and hepatic levels of xanthine oxidase. The maximum value of serum uric acid and creatinine was 349.3 μmol·L^-1 and 26.4 μmol·L^-1, respectively, in mice injected with PO combined with Hx. The levels of liver xanthine oxidase and 24 h albuminuria were significantly increased in mice injected with PO combined with Hx (P < 0.01). Pathological data showed that renal tubules were dilated, the epithelial cells of renal tubules were disordered, and the production of collagen fibers, reactive oxygen species (ROS) and lipid peroxidase 4-hydroxynonenal (4-HNE) were slightly increased after intragastric administration of PO combined with Hx mice. Obvious infiltration of inflammatory cells and large area of collagen deposition, with a large amount of ROS and the lipid peroxide 4-HNE were produced in mice injected with PO combined with Hx. Western blot analysis showed that the expression of fibronectin (FN) and urate transporter 1 (URAT1) was increased after intragastric administration of PO combined with Hx in mice and further increased in mice injected with PO combined with Hx. This study demonstrates that injection with 100 mg·kg^-1 potassium oxonate combined with 500 mg·kg^-1 hypoxanthine establishes a stable and efficient mouse HN model.

Although current synthetic anti-gout drugs have significant therapeutic effects in reducing serum uric acid levels, they have serious side effects such as allergic reactions and liver and kidney damage. Natural products with a wide range of uric acid-lowering and high safety have played a critical role in anti-gout drug discovery and development. This paper reviews the natural products with uric acid-lowering or anti-gout pharmacological effects and the investigation on their mechanisms of action, to provide information for drug discovery and development.

The MYC gene, one of the most common dysregulated driver genes in human cancers, is composed of three paralogous genes C-MYC, N-MYC and L-MYC. It is abnormally activated in more than half of cancer types. Since MYC plays an important role in the formation, maintenance and progression of cancer, targeting MYC is an effective strategy for cancer treatment. As a potential anti-cancer target, MYC is considered "undruggable" because it lacks a suitable pocket for accommodating small molecule inhibitors. Recently, under the guidance of protein structure information and many computational tools, many indirect strategies to inhibit MYC have emerged and shown favorable anti-cancer effects in tumor models. In this paper, the recent small molecules that indirectly target MYC are divided into inhibitors acting on the protein-protein interaction (PPI) among MYC and other proteins, and targeting inhibitors regulating MYC action. Additionally, the introduction and assessment towards compounds with different mechanisms are summarized to provide reference for the further research of MYC inhibitors.

Molecular glues are a class of small molecules that induce the formation of protein-protein interactions to confer new biological function or therapeutic effects. As a unique pharmacological modality, molecular glues could target proteins without druggable binding pockets. It exhibits a variety of functions, including regulating signal transduction, stabilization or degradation of targeted proteins, through sticking different proteins together. This review will summarize the development and current status of molecular glues derived from natural products and analogs by illustrating the discovery and interaction mechanism. We hope to present a systematic view, provide valuable clues for researchers and encourage them to explore more efficient and rational molecular glue discovery strategies.

Panax quinquefolium L. is a valuable Chinese herbal medicine with a large market demand. It has a complex chemical composition and numerous biological activities. At present, research on P. quinquefolium is focused on its underground parts, with especial interest in its saponins. There are few studies on non-saponins and the aboveground parts of Panax quinquefolium. Current quality standards are based on the saponin contents, which does not address the other benefits of Panax quinquefolium. This paper summarizes progress on the chemical components, pharmacological effects, quality evaluation, and product development of P. quinquefolium in recent years, and provides references for its further R & D and comprehensive utilization.

The high mortality of tumor is one of the most urgent problems to be solved. However, the current clinical trials provide limited quantitative descriptions on dynamic changes of drug efficacy, which restrict the selection of dosing regimens. Quantitative systems pharmacology (QSP) is a new approach for precise treatment of tumors. It quantifies the network relationship between drug action and diseases by integrating the tumor growth and molecules, cells in vivo, thereby predicting the efficacy, toxicity, and mechanism of antitumor drugs as well as identifying predictive biomarkers. In this review, we provide an overview of definition of QSP, current approaches and typical applications in research of antitumor drugs to enhance our understanding of QSP.

The quality of traditional Chinese medicine has a direct impact on the effectiveness and safety of its use, and is the premise necessary to ensure the healthy development of the traditional Chinese medicine industry. Comprehensive and accurate control and evaluation of the quality of medicinal materials is of great significance to the traditional Chinese medicine industry, but the complexity and dynamics of the chemical composition of medicinal materials makes their quality evaluation a challenge. Plant metabolomics provides an integrated and comprehensive analysis that is consistent with the holistic approach of traditional Chinese medicine. Chemical information therein promotes the establishment of a traceable system and provides new ideas and methods for the quality evaluation of medicinal materials. Plant metabolomics in the quality evaluation of medicinal materials is gradually increasing, and the core is the screening and identification of differential metabolites or specific marker compounds by means of stoichiometry. This study focused on the main factors that affect the quality of medicinal materials, such as origin, environmental adversity, varieties, harvest time, commercial specification and TCM processing. We describe the research progress in plant metabolomics combined with chemometrics analysis for the quality control and evaluation of medicinal materials, summarize existing problems, identify trends, and propose future research directions. Metabolomics plays an increasingly important role in the quality evaluation of medicinal materials, but the absolute qualitative and quantitative information of metabolomics needs to be further developed, and a single 'omics' technique is not sufficient for an in-depth analysis of medicinal value. In the future, standardization of plant metabolomics methods and a more complete database should be actively promoted, and plant metabolomics should be integrated into quality marker exploration. Plant metabolomics will need to be integrated with other 'omics' methods to improve the quality and evaluation system of medicinal materials.

Glioblastoma is a malignant tumor in central nervous system, which has strong invasion, poor prognosis and short survival time. At present, the main treatment strategy of glioblastoma is surgical excision, supplemented by radiotherapy and chemotherapy. However, due to incomplete resection and high recurrence rate, it is urgent to find novel therapeutic method for glioblastoma. Photodynamic therapy, as a promising non-surgical treatment, provides a new strategy for postoperative adjuvant therapy of glioblastoma. This review summarizes the mechanism and clinical application of photodynamic therapy mediated by various photosensitizers in glioblastoma, in order to provide help for the treatment of glioblastoma.

There is a broad and urgent need for the clinical application of anticancer nanomedicine in tumor therapy, but the complex biological barrier in solid tumors has always been the main obstacle to infiltrating nanomedicine into the tumor. The traditional design of nanomedicine based on enhanced permeability and retention (EPR) effect still has some limitations in tumor permeability, it is urgent to find other design theories. Therefore, this review summarizes two novel strategies, active transcytosis and immune cell-mediated tumor penetration, for promoting tumor penetration of anticancer nanomedicine.

In recent years, the use of the body's immune system for anti-tumor immunotherapy has received extensive attention. However, the immunosuppressive tumor microenvironment (TME) limits the effect of immunotherapy. Therefore, overcoming the limitations of TME and immunosuppressive cells plays an important role in tumor immunotherapy. Nano agents have great potential to reprogram the immunosuppressive microenvironment and provide an effective strategy for immunotherapy. With the continuous development of active targeting nano carrier technology and the deepening of the research on drug action sites, subcellular organ targeting nano carrier materials with more accurate active targeting function have also attracted more and more attention. This review will briefly introduce the relationship between subcellular organelles and tumor, summarize the design strategy and research progress of targeted nano drug delivery system based on the characteristics of acidity, reactive oxygen species (ROS) activity, immunogenicity, and TME of immunosuppressive cells, to provide reference for the construction of subcellular pathway targeted drug delivery system in tumor immunotherapy.

Particle design, based on the concept of "quality by design", combines the elements of microbiology, formulation science, heat and mass transfer, solid state physics, powder science, and nanotechnology. It is widely used to develop particles with excellent functional properties. Without affecting the active ingredients, the modification technology of traditional Chinese medicine (TCM) powder based on particle design theory, could improve the flowability, tabletability, disintegration and dissolution behavior, hygroscopicity, wettability, and other functional properties at the physical structure level. This greatly promotes the development of solid preparations of TCM. The present review aims to summarize and discuss the research progress of powder modification of TCM from the perspective of the theory of particle design, powder modification technology, equipment used for powder modification, application in TCM and modification mechanism mainly based on researches published in recent ten years. This review could provide ideas and theory basis for the development of particle design.

Silk fibroin is a natural polymer with certain water solubility, structural modification, good biocompatibility and biodegradability, which can be used as a drug delivery carrier material. As a promising drug delivery system, drug-loaded silk fibroin nanoparticles can control drug release, reduce toxicity and improve therapeutic effects. In this paper, the basic characteristics of silk fibroin, the preparation methods of drug-loaded silk fibroin nanoparticles and the application of silk fibroin in nanoparticulate drug delivery systems are reviewed, and on this basis, the further development of drug-loaded silk fibroin nanoparticles is prospected.

The mitochondrial enzyme glutaminase C (GAC) is highly expressed in a variety of cancer cells, resulting in increased glutamine metabolism and cancer development. Therefore, GAC has become a potential target for anti-tumor drug development. However, current GAC inhibitors shared similar structural characteristics, few new scaffolds were reported. By conducting a prokaryotic Escherichia coli expression system, human GAC protein of high-purity was obtained through lysozyme digestion combined with ultrasound dissociation, and cobalt magnetic beads purification, Moreover, we performed studies to validate interaction between small molecules and GAC protein through thermal shift assay, drug affinity responsive target stability assay, protein crosslinking and GAC enzyme activity detection. Meanwhile, a comprehensive small molecule-protein interaction confirmation and systematic pharmacodynamic study in vitro were carried out on compound C19, which was a reported GAC inhibitor screened from the Enamine database. Results showed that C19 directly bind to GAC protein, disturbed GAC tetramers formation, and inhibited its enzyme catalytic activity. By interfering GAC function, C19 dose-dependently suppressed GAC-mediated glutamine metabolism, reduced glutamate in cancer cells, and thus alleviated A549 and NCI-H1299 non-small cell lung cancer cell growth. Together, C19 was identified as a lead compound, providing a new strategy for the structural design of drugs targeting GAC.

To investigate the effect of Fufang yinhua jiedu (FFYH) granules against coronavirus and its potential mechanism, we used Huh7, Huh7.5, H460, and C3A cell lines as in vitro models to evaluate the cytotoxicity and antiviral activity of FFYH by observation of cell pathogenic effect (CPE); and then the inhibitory effect of FFYH on the transcription expression of coronavirus RNA and inflammatory factor mRNA were evaluated by quantitive reverse transcription PCR (qRT-PCR); finally, the inhibitory effect of FFYH on the expression of coronavirus protein and its underlying mechanism against coronavirus were investigated by Western blot and immunofluorescence. Our results indicated that 50% toxic concentration (TC₅₀) FFYH on Huh7, Huh7.5, H460, and C3A cells were 2 035.21, 5 245.69, 2 935.28 and 520 µg·mL^-1, respectively; 50% inhibitory concentration (IC₅₀) of FFYH on HCoV-229E in Huh7 and Huh7.5 cells were 438.16 and 238.54 µg·mL^-1 with safety index (SI) of 4.64 and 21.99, respectively; IC₅₀ of FFYH on HCoV-OC43 in H460 cells was 165.13 µg·mL^-1 with SI of 17.78. Moreover, FFYH not only could inhibit the replication of coronaviruses (HCoV-OC43 and HCoV-229E) through inhibiting the transcription of viral RNA and the expression of viral protein, but also effectively suppress the expression of inflammatory factors interleukin-6 (IL-6), tumor necrosis factor α (TNF-α) and interleukin-8 (IL-8) at mRNA level caused by coronaviruses, which might be associated with the inhibitory effect of FFYH on mitogen-activated protein kinase (MAPK) pathway and the nuclear translocation of nuclear transcription factor-κB (NF-κB). In summary, our results demonstrated that FFYH exhibited a good in vitro anti-coronavirus effect, which provides a theoretical basis for its clinical use in the treatment of anti-coronavirus pneumonia.

This study was designed to obtain recombinant human thioredoxin (rhTXN) by gene cloning and prokaryotic expression, and evaluated its therapeutic effect in the mouse ulcerative colitis (UC) model induced by dextran sulfate sodium (DSS). The human thioredoxin gene TXN was cloned from the cDNA of Jurkat cells. The recombinant expression plasmid pCold TF-rhTXN was constructed by restriction enzyme digestion. After expression in E. coli BL21 (DE3), recombinant human thioredoxin was purified by a nickel column. Intact rhTXN recombinant protein was obtained after removal of the fusion partner-tag by enzyme digestion and the activity of disulfide reductase was detected by the insulin reduction method. The animal experiments in this study were performed in accordance with the ethical guidelines of the Laboratory Animal Welfare Ethical Review Committee of Nanjing University. Experiment ulcerative colitis was induced by providing mice with sterilized drinking water which contained 3% DSS. rhTXN was injected intraperitoneally. The therapeutic effect was studied by weight change, colon length and HE (hematoxylin and eosin) stained sections. In vivo imaging was used to study the targeting of rhTXN to DSS mice. The GSE107499 data set of GEO database was used to screen the hub genes at the lesional sites of UC and study the correlation with TXN. The experimental results showed that rhTXN was successfully expressed and purified with disulfide reductase activity. rhTXN (100 μg·kg^-1) had a significant therapeutic effect on maintaining the weight change of mice (P = 0.000 5) and reducing intestinal injury (P < 0.000 1), and had a colon targeting effect on DSS mice. In GSE107499 data set, TXN in inflammatory sites of UC patients was significantly down regulated (P < 0.01) and negatively correlated with hub gene CD40 (P < 0.01) and positively correlated with hub gene fibronectin 1 (FN1) (P < 0.01). In this study, biologically active rhTXN was successfully prepared and proved to have a promising therapeutic effect on the DSS mouse model, and TXN gene was significantly correlated with the UC hub genes CD40 and FN1.

As a member of the human epidermal growth factor receptor (HER) family of receptor tyrosine kinases, HER3 is an aberrantly activator of the PI3K/AKT pathway. Studies have indicated that HER3 is related to the progression of a variety of tumor types such as breast cancer, non-small cell lung cancer (NSCLC), ovary cancer and colon cancer, and in acquired resistance to EGFR and HER2 therapies. However, the attempts to target HER3 with neutralizing antibodies are not ideal previously. This is most likely due to the fact that the antibodies targeting HER3 fail to completely block the heterodimerization of HER3 and other receptors. Antibody-drug conjugates (ADCs) can specifically bind to target cells and exert the highly cytotoxicity effect on cancer cells through chemical drugs. ADCs have been widely used in clinical cancer therapies. We analyzed and optimized the structure of the antigen-antibody complex between HER3 and antibody LmAb3 by computer-aided molecular simulation technology, and the key sites involved in antigen binding in LmAb3 were predicted by distance geometry and computer graphics technology. Then a novel anti-HER3 antibody FD001 was obtained by point mutation technology. The affinity measurement by ForteBio results showed that the affinity of FD001 is much higher than LmAb3, the K_D values of FD001 and LmAb3 with HER3 were 1.48E-11 and 2.46E-10, respectively. Antibody drug conjugate FD001-DM1 is obtained by coupling FD001 to DM1 [emtansine, N²'-deacetyl-N²'-(3-mercapto-1-oxopropyl)-maytansine] by lysine coupling technology. The results of cell cytotoxicity experiments showed that FD001-DM1 could effectively inhibit the proliferation of HER3-positive HT-29 colon cancer cells, with EC₅₀ value of 33.62 nmol·L^-1. The in vivo xenografts therapy results showed that the tumor volume of the FD001-DM1 treatment group was about 25% of that of the control group, and there was no significant weight reduction of the mice. These results reveal that FD001-DM1 had good in vivo and in vitro anti-tumor activity with high safety, which may provide effective help for further exploration of HER3-targeted ADCs drugs. The mice in this study were used and treated in accordance with international laboratory animal care and use guidelines and approved by the Animal Ethics Committee of the Military Cognitive and Brain Science Institute of the Military Medical Research Institute.

Five new megastigmanes (1-5) were isolated from a decoction of Uncaria rhynchophylla by separation techniques of column chromatography using a combination of multiple stationary phases, including macroporous adsorbent resin, MCI resin, silica gel, Sephadex LH-20, and Toyopearl HW-40F, and reversed phase HPLC. Their structures were characterized by spectroscopic data analysis of HR-ESI-MS, NMR, and CD, in combination with Mosher's mothed as well as ECD and NMR calculations. The new compounds were named uncarphyllonone A (1), uncarphyllonols A (2) and B (3), and uncarphabscisic acids A (4) and B (5). Although the structures of 3 and 4 were previously reported, the reported NMR spectroscopic data were incorrect or do not support the assigned structures in literatures. This is also the first report of discovery of new megastigmane natural products from the Uncaria genus.

Seven nucleoside compounds were isolated from the Oenothera biennis L. by various chromatographic techniques such as Diaion HP-20, silica gel, Sephadex LH-20, MCI and semi-preparative HPLC. Their structures were identified by analysis of physicochemical properties and spectral data, and determined as 9-(3′-carbonyl methyl)hydroxypurine (1), 1-(3′-carbonyl methyl)purine-6, 8-dione (2), N-methyl-2-pyridone-5-carboxamide (3), uracil (4), uridine (5), thymidine (6) and 2′-Ο-methoxy luridine (7). Compound 1 is a new nucleoside and compounds 2-7 were newly isolated from the Oenothera biennis L. Compounds 1-2 can significantly increase the viability of BEAS-2B cells induced by TGF-β1, showing potent anti-pulmonary fibrosis activity.

Four compounds were isolated from the 70% EtOH extract of Ardisia crispa by using various chromatographic techniques, including silica gel, ODS and semi-preparative HPLC. The structures of 1-4 were elucidated based on physicochemical properties and spectroscopic data. These compounds were defined as crispalactone A (1), (+)-pinoresinol (2), 3, 5-dimethoxy-4- hydroxyphenol-1-O-β-D-glucopyranoside (3) and (+)-schizandriside (4). Compound 1 is a new γ-valerolactone derivative, and compounds 2-4 are firstly isolated from Ardisia crispa.

Sixteen compounds were isolated from the ethanol extract of Illigera rhodantha by silica gel, ODS, and Sephadex LH-20 column chromatographies. These compounds were identified as (2R, 3R)-2, 3-dihydroxy-2-methylbutane-1, 4-diyldibenzoate (1), p-hydroxyphenethyl trans-ferulate (2), 4-O-benzoyl-2-C-methyl-D-erythritol (3), N-trans feruloyl-3-methyldopamine (4), tribulusamide A (5), cryptomeridiol (6), teuclatriol (7), oleanolic acid (8), icario A₂ (9), vanillic acid (10), p-hydroxybenzoic acid (11), gallic acid (12), ethyl gallate (13), chrysophanol (14), D-1-O-methyl-inositol (15), and hexadecanoic acid (16) based on their spectral data and physico-chemical properties. Compound 1 is an undescribed compound, of which its absolute configurations were determined by Mosher and ROESY methods; all the compounds except 10, 11 and 14 were isolated from Illigera genus for the first time. Compared with the positive control indomethacin, compounds 4-6, 8 and 9 inhibited significantly against the NO production in LPS-induced RAW 264.7 cells.

Twenty compounds were isolated from the ethyl acetate extract of Smilax glabra by using various chromatographic techniques, including macroreticular resin, silica gel, Sephadex LH-20 and semi-preparative HPLC. Their structures were elucidated by physicochemical properties, MS and spectroscopic data. These compounds were elucidated as glabraside A (1), glabraone A (2), 5-hydroxy-3ʹ, 4ʹ, 7-trimethoxy-flavanone (3), naringenin (4), quercetin 7-O-α-L-rhamnoside (5), neoastilbin (6), neoisoastilbin (7), isoastilbin (8), eriodictyol-7-O-β-D-glucopyranoside (9), naringenin-7-O-α-L-rhamnoside (10), kaempferol 3-O-[4′′′′′-O-acetyl-α-L-rhamnosyl-(1→6)]-[β-D-glucopyranosyl-(1→2)]-β-D-glucopyranoside (11), 5-hydroxymaltol (12), 3, 4, 5-trimethoxyphenyl-1-O-β-D-glucopyranoside (13), 2-(3′, 4′-dihydroxyphenyl)-1, 3-benzodioxole-5-aldehyde (14), kompasinol A (15), (+)-syringaresinol (16), cis-resveratrol (17), trans-resveratrol (18), flufuran (19) and 5-hydroxymethyl-furaldehyde (20). Two new compounds (1 and 2) showed inhibitory activity toward nitric oxide (NO) production, with IC₅₀ values of 56.8 and 29.5 μmol·L^-1, respectively.

The ethyl acetate part of the alcoholic extract of Cordia dichotoma fruits was purified by a combination of normal-phase silica gel column chromatography, Sephadex LH-20 gel column chromatography and semi-preparative HPLC, and the structure was identified by modern spectroscopic techniques (UV, IR, MS, NMR). A total of 10 compounds were isolated and identified as cordilide (1), (S)-2-hydroxy-3-(4′-hydroxyphenyl) propanoic acid (2), vanillic acid (3), p-coumaric acid (4), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)propan-1-one (5), benzoic acid (6), p-hydroxypropiophenone (7), p-hydroxyacetophenone (8), 5′-methoxyevofolin B (9) and vanillin (10). Among them, compound 1 is a pair of new phenylpropanoid enantiomers, and compounds 3, 6, 8 and 9 were isolated for the first time from the genus.

Saponins and sterones are two main characteristic components in Achyranthis Bidentatae Radix. In order to control the quality of Achyranthis Bidentatae Radix more effectively, a high-performance liquid chromatography (HPLC) method was established by using double external standards calibration method (DESCM) for simultaneous determination of the contents of achyranthoside C, achyranthoside D, β-ecdysterone, 25R-inokosterone and 25S-inokosterone in Achyranthis Bidentatae Radix. Chromatographic separation was achieved on an Agilent Poroshell 120 EC-C18 (150 mm × 4.6 mm, 2.7 μm) using 0.1% phosphoric acid in water and 0.1% phosphoric acid in acetonitrile as mobile phase. The flow rate was 0.8 mL·min^-1 and the column temperature was set as 35 ℃, the injection volume was 5 μL and the total analytical time was 30 min. β-Ecdysterone was used as the reference to calculate the relative correction factors (RCF) and relative retention time (RRT) of 25R-inokosterone and 25S-inokosterone, achyranthoside D was used for achyranthoside C. The RCFs of 25R-inokosterone, 25S-inokosterone, and achyranthoside C were 1.116, 1.056, and 0.888 1, respectively. The double external standards calibration method (DESCM) and external standard method (ESM) were used to calculate the contents of five ingredients in Achyranthis Bidentatae Radix samples from different sources and the variation between the results was within acceptable limits (RE ≤ 5%). The results showed that the contents of two saponins and three sterones of Achyranthis Bidentatae Radix were 0.597%-1.916% and 0.044%-0.150% respectively. The total content of saponins was about 10 times that of sterones. In conclusion, the established DESCM allowed simultaneous determination of five ingredients (achyranthoside C, achyranthoside D, β-ecdysterone, 25R-inokosterone, and 25S-inokosterone) in Achyranthis Bidentatae Radix, providing a scientific and feasible overall quality evaluation method for Achyranthis Bidentatae Radix.

This study establishes and optimizes the physiologically based pharmacokinetics (PBPK) model for dapagliflozin, predicts the drug distribution into relevant tissues, and calculates the inhibitory effect on the sodium-glucose cotransporters (SGLTs) in the intestine and renal proximal tubule. Based on literature data, a PBPK model for oral administration in healthy adults was established and the predicted blood concentration-time curve characteristics, the main pharmacokinetic parameters (PK), and drug excretion in urine were compared with the published data. To verify and optimize the model and verify the accuracy of the tissue distribution and concentration predictions, a pharmacodynamics model (PD) was established. Urine glucose excretion (UGE) was simulated at the corresponding times. The characteristics of the drug-time curve predicted by the model are similar to those of the measured curve, and the ratio of the main PK parameters to the measured values is within a two-fold range; the accuracy of the established PBPK model is good. The maximal inhibition obtained with 10 mg of dapagliflozin on the duodenum and jejunum segment sodium-glucose co-transporter 1 (SGLT1s) was 1.6%-4.7%, and the inhibition rate of the sodium-glucose co-transporter 2 (SGLT2s) in the proximal tubule of the kidney was as high as 99.9%. At a dose of 10 mg, dapagliflozin delayed intestinal glucose absorption while occupying most of the sites (99.9%) of the renal sodium-glucose cotransporter 2 and inhibiting its glucose reabsorption. This physiological-pharmacokinetic model for dapagliflozin in healthy adults can provide meaningful guidance for exploring pharmacological mechanisms and potential toxicity of gliflozin by simulating drug distribution in different tissues.

This study establishes a quantitative analysis of multi-components by single marker (QAMS) method for the simultaneous determination of gallic acid, sodium danshensu, protocatechuic acid, protocatechuic aldehyde, vanillin, rosmarinic acid, salvianolic acid B, eugenol, cryptotanshinone and tanshinone II_A in Guanxinshutong capsules (Bambusae Concretio Silicea, Salvia miltiorrhiza, clove, borneol, Bambusae Concretio Silicea) by HPLC. Sample was loaded onto an Agilent C18 (ZORBAX Extend-RP C18, 250 mm × 4.6 mm, 5 µm) column and eluted with methanol-0.4% aqueous formic acid solution as a flow phase gradient, flow speed 1.0 mL·min^-1, detection wavelength 280 nm, column temperature 35 ℃ and sample intake of 5 µL. Using protocatechuic acid as the internal reference, a relative correction factor was calculated and the durability was investigated, and the content of 10 components was calculated by QAMS and external standard method (ESM). The results show that the specificity, linear relationship, precision, repeatability, and stability of the 10 components were good. The average recovery was 98.20%-103.47% and RSD was 1.26%-2.84%. The relative positive factors and contents of the other nine components were calculated as gallic acid (0.759, 227.381), sodium tanshinol (3.630, 3.283), protocatechualdehyde (0.185, 0.150), vanillin (0.532, 65.213), rosmarinic acid (4.240, 1.035), salvianolic acid B (3.245, 18.204), eugenol (1.729, 9.265), cryptotanshinone (0.691, 1.449), and tanshinone Ⅱ_A (0.702, 1.939). The results of QAMS were consistent with ESM analysis, and the relative error was between -3% and 3%. This method is stable and reliable, and can be used for the determination of 10 components in Guanxinshutong capsules.

This study aims to construct a dynamic two-dimensional characterization technique for the hygroscopicity of traditional Chinese medicine extracts and investigate the effect of material properties of powders on hygroscopicity. The dynamic hygroscopicity-time curves of the powders were measured at 25 ℃ and 75% humidity, and the semi-equilibrium hygroscopicity time (t_1/2) and equilibrium hygroscopicity (F^∞) were derived as two-dimensional evaluation indicators. Finally, the correlation between the material properties and the hygroscopic behavior was analyzed by principal component analysis (PCA) and partial least squares analysis (PLS). The results showed that the dynamic two-dimensional characterization system of hygroscopicity constructed with 1/t_1/2 = 0.1 h^-1 and F^∞ = 15% as the center can classify the hygroscopic behavior of traditional Chinese medicine extracts into four categories: fast hygroscopicity with strong hygroscopicity, slow hygroscopicity with strong hygroscopicity, fast hygroscopicity with weak hygroscopicity and slow hygroscopicity with weak hygroscopicity. The moisture absorption was negatively correlated with D₅₀, D₉₀, ρ_b and ρ_t; the moisture absorption rate was negatively correlated with D₁₀, D₅₀, D₉₀, ρ_b, ρ_t, and positively correlated with moisture content. The hygroscopicity dynamic two-dimensional characterization indicators of Chinese medicine extracts (CMEs) constructed in this study matched with the physical properties. The method of dynamic multi-dimensional characterization technology is feasible and scientific, and the idea has strong promotional value.

Leech bites usually lead to more bleeding, and dermal tissue is damaged to form lifelong scars. If leeches enter the body cavity, it will be more dangerous. Therefore, there is an urgent need to develop effective repellents. In this study, oil in water (O/W) emulsion of tea tree oil was prepared with tea tree oil as the main ingredient, and konjac glucomannan (KGM), ethyl cellulose (EC) as the main excipients. The filter-paper ring method and repellent test in water were used to evaluate the repellent effects on leeches. The animal experiments were approved by the Ethics Committee of Academy of Military Medical Sciences and were conducted in accordance with relevant guidelines and regulations. The activities of acetylcholinesterase (AchE), glutathione S-transferase (GST) and carboxylesterase (CarE) in vivo were measured to clarify the repellent mechanisms. The results showed that a uniform and stable tea tree oil emulsion was successfully prepared, which has excellent hydrophilicity and can effectively repel leeches. The tea tree oil emulsion has a good repellent effect on leeches, which can avoid the volatilization of tea tree oil and prolong the effective repelling time. The novel formulation of tea tree oil provides a new idea for repelling effects with long time and high efficiency based on similar essential oil.

It is a common understanding that turbidity and precipitation of traditional Chinese medicine are easy to occur in the process of decocting. At present, our research group found that the cause of "multi-phase of traditional Chinese medicine decoction" mainly came from the interaction between the effective components of traditional Chinese medicine, especially the interaction of acid and base components. For example, the Liquorice and Rhizoma chinensis was a supramolecular system formed by a large number of active components in the decoction (> 30%), and could stably exist in the decoction system. In this study, the supramolecular part was extracted, and the morphology of the supramolecular part was characterized by scanning electron microscopy and dynamic light scattering. It was observed that the supramolecular particles were uniform in size and regular in shape. The main components of supramolecular sites were identified by liquid mass spectrometry (LC-MSⁿ). The results of UV and IR spectra showed that the chemical components of Liquorice and Rhizoma chinensis in the co-decocting process collided with each other, and weak bonds were formed between the functional groups of the molecules, which then induced the aggregation to form supramolecules. Thereafter, Through the diarrhea model of mice, sensory evaluation and antibacterial activity evaluation found that Liquorice and Rhizoma chinensis decocted together enhanced the antibacterial activity of Rhizoma, and compatibility "reconcile" Rhizoma "big bitter cold" property compared with single decoction group and interval administration group. All animal experiments were approved by the Animal Ethics Committee of Beijing University of Chinese Medicine, and the relevant regulations of Beijing University of Chinese Medicine on experimental animals were strictly followed. In this study, supramolecular chemistry method was used to preliminarily discuss the scientific connotation of "increasing efficiency and decreasing toxicity" of Liquorice and Rhizoma chinensis combined decoction from three perspectives of "property, efficacy and taste", and provide new ideas for the basic research of "reconcile" compatibility of Liquorice.

In order to reveal the molecular mechanism of the small heat shock proteins (sHSPs) involved in stress resistance and active ingredients accumulation in Salvia miltiorrhiza, a small heat shock protein gene was cloned from Salvia miltiorrhiza by reverse transcription PCR according to the transcriptome data of orange root Salvia miltiorrhiza. The gene is named SmHSP21.8 based on the molecular weight of the protein, and it contains an open reading frame of 585 bp, which encodes 194 amino acids. The results of phylogenetic analysis and amino acid sequence alignment showed that SmHSP21.8 protein belongs to the endoplasmic reticulum (ER) subfamily, and contains a conserved endoplasmic reticulum-specific DPFR-I/V-LE-H/Q-x-P motif at N-terminus. The prokaryotic expression vector pMAL-c2X-SmHSP21.8 was constructed and transformed into E. coli BL21 competent cells. The recombinant protein was successfully expressed after inducted. Temporal and spatial expression analysis showed that SmHSP21.8 gene was the highest expressed in flowers and had significant tissue specificity. The relative expression of the gene was significantly increased in seedlings after induction by 38 ℃, PEG6000, abscisic acid(ABA), and indole-3-acetic acid (IAA), indicating that SmHSP21.8 gene may be involved in abiotic stress such as high temperature and drought, as well as the response to exogenous hormones ABA and IAA. These results lay the foundation for further research on the molecular mechanism of small heat shock proteins involved in adversity stress.