ArchiveInjury of vascular endothelial barrier function is implicated in several pathophysiological processes. The integrity of vascular endothelium is regulated by cytoskeleton and cell-cell junctions. Small guanosine triphosphatases of the Rho family (Rho GTPases) are known to play a central role in vascular endothelial barrier function. It has been reported that RhoA, Rac1, Cdc42 and RhoB are involved and they exert both positive and negative effect on endothelial barrier integrity, depending on their subcellular location. When inflammatory factors such as thrombin attack the vascular endothelial cells, GEF of RhoA will be widely distributed throughout the cells. Thus, activated RhoA causes aggregation of F-actin fibers in a short time and disrupts the vascular endothelial barrier, a process named acute cell contraction. However, RhoA may also induce the production and maturation of intercellular junctions in new cells. Rac1 and Cdc42 help to maintain the integrity of vascular endothelial barrier at the resting state. They cause the phosphorylation of LIM kinase and inhabitation of cofilin, resulting in less remodeling of cytoskeletal in the vascular endothelial cells. On the other hand, Cdc42 can translocate to the cortex rapidly after a stimulation, where Cdc42 will activate the myosin Ⅱ and promote the reorganization of adjective junction to facilitate the recovery of vascular endothelial barrier. In this review, we overviewed how Rho GTPases regulate the vascular endothelial barrier integrity.
Chemotherapy plays an essential role in controlling tumor growth and progression. However, long-term use of chemotherapeutic drugs usually results in drug resistance in tumor cells, leading to treatment failure and disease progression. The mechanism of tumor resistance to chemotherapy and the strategy of prevention or reversal of such resistance have always been hot issues in cancer therapy research. Exosomes are small spherical vesicles secreted by cells with a diameter of 40-100 nm. They carry a variety of bioactive small molecules (including DNA, ncRNA, RNA, and proteins) and participate in regulation of cell microenvironment, thereby affecting a variety of physiological and pathological activities in the body. In recent years, studies have shown that exosomes play an important role in cancer cell resistance to chemotherapy, metastasis, and immune escape. This article reviews the role and mechanism of exosomes in the development of drug resistance in tumors, and aims to provide new ideas for the prevention or treatment of tumor resistance.
Lorlatinib (PF-06463922) is a highly selective and potent third generation anaplastic lymphoma kinase (ALK) inhibitor with dual activity against c-ros oncogene 1, a receptor tyrosine kinase (ROS1). In November 2018, the US Food and Drug Administration approved lorlatinib for treatment of disease progression in ALK-positive and late-stage NSCLC patients who receive the treatment with crizotinib and at least one of other ALK inhibitors; and those with disease progression after treatment of alectinib or ceritinib as the first ALK inhibitor. The results of Phase Ⅰ/Ⅱ clinical trials showed that it has effective initial anti-tumor activity, strong intracranial therapeutic activity, with less tolerance and safety issues. This paper systematically reviewed the chemical structure, mechanism of action, pharmacodynamics, pharmacokinetics, usage and dosage, clinical research, safety and upcoming research fields of lolatinib, to provide an update on clinical or laboratory research and clinical practice.
Adaptation to hypoxia of the plateau environment has been a focus of scientific research in decades. The geographical distributions of such living environment include the Qinghai-Tibet Plateau, Andean Plateau in South America and Ethiopian Plateau. Over the past century, the unique features of physiological adaptation to high-altitude chronic hypoxia have been documented scientifically. The genetic studies of hypoxic adaptation in the past decade have revealed genetic bases of human high-altitude adaptation, with a close relationship to the hypoxia inducible factor (HIF) pathway and hypoxia response elements (HREs). Interestingly, the genetic pattern of adaptation to hypoxia is not the same among the three plateau populations. Tibetan has developed the best high-altitude adaptation, with modification of the HIF pathway as the key genetic element. Due to the wide range of HIF pathways, HIFs could regulate hundreds of downstream genes and are closely related to various diseases such as cancer, inflammation, ischemia, acute organ damage and infection, etc. The treatment researches of these diseases through HIFs-related regulations have led to the development of stabilizers and inhibitors of HIF pathway. We review here the adaptive responses of the three plateau populations to the hypoxic environment, and the genetic mechanism of HIF and HREs in the different ethnic high-altitude populations. Classes of HIF inhibitors, such as PI3K and/or mammalian target of rapamycin (mTOR) inhibitors, DNA-binding inhibitors, histone deacetylase inhibitors, heat-shock protein 90 inhibitors, cardiac glycosides, transcription inhibitors, topoisomerase inhibitors, and HIF activators including 2-OG mimics, Fe2+ chelators, prolyl hydroxylase (PHD) active-site blockers and CUL2 deneddylators have been presented with the drug examples. In addition, the top 3 chemical-disease and chemical-gene (protein) co-occurrences have been presented from the Pubmed literature search. The review could serve as references for research of hypoxia adaptation and HIF-related diseases.
Protein-protein interaction (PPI) plays an important role in many steps of the human immunodeficiency virus (HIV) life cycle. Targeting these protein-protein interactions, especially the interaction between the virus with host cells, can provide new insights into the development of HIV inhibitors with novel mechanisms of action. Herein, we review the latest discoveries of PPI inhibitors based on the mechanisms of action of various protein-protein interactions with specific research examples.
The blood brain barrier can selectively block the uptake of xenobiotics from peripheral blood into the brain. Although this is important for maintaining the stability of the brain environment and normal function of the central nervous system, it presents a challenge for delivery of therapeutic drugs to the brain. Passive brain-targeting drug carrier is able to increase the drug concentration in the brain by enhancing the affinity to blood-brain barrier and/or inhibiting the efflux absorbed drug via P-glycoprotein. The active brain-targeting drug carrier can be obtained by linking specific ligands or antibodies onto passive target carriers to achieve precise delivery of drugs to the brain. Dual targeting drug carriers obtained by combining tumor cell targeting with brain targeting have shown their advantages for treatment of brain tumors. The targeted drug delivery to brain will provide a unique manner for the treatment of brain diseases such as Alzheimer's, Parkinson's, brain tumors, and stroke. Among the drug delivery systems of passive brain-targeting, active brain-targeting and dual brain-targeting, we evaluated the strategies to improve brain drug delivery efficiency, such as by reducing carrier size, opening tight junctions between cells at the blood-brain barrier, incorporating hydrophilic groups on the surface of the carrier, and alternative intranasal drug administration.
In ischemic stroke, increased level of neuronal complex of nitric oxide synthase (nNOS)-postsynaptic density protein-95 (PSD-95) plays an important role in neuronal damage. We aimed to establish a screening model to identify compounds capable of uncoupling nNOS interaction with PSD-95. In this model, human embryonic kidney-293T (HEK-293T) cells were transfected with either pCDH-Flag-nNOS or pcDNA3.1-PSD-95 plasmid to obtain the protein of Flag-nNOS or PSD-95. Incubating Flag-nNOS with PSD-95 causes formation of the nNOS-PSD-95 complex. ZL006, a known uncoupler of nNOS-PSD-95 interaction, can disturb the interaction between Flag-nNOS and PSD-95, serving as a positive control. The method coupling antibodies to magnetic beads with glutaraldehyde was used to decrease the cost and increase the efficiency. To establish that our model is suitable for selecting nNOS-PSD-95 uncouplers, we evaluated the ability of IC87201, another reported uncoupler of nNOS-PSD-95 interaction, and structural analogs of ZL006. IC87201 and one structure analog of ZL006 showed uncoupling effect, supporting that our model can be used to select different types uncoupler blocking nNOS-PSD-95 interaction.
A hyper-bilirubin cell model was established for its relevance to the pathological state of jaundice in human. This model was used to screen for the pharmacological components of Yin-Zhi-huang (YZH). Total bilirubin, indirect bilirubin in cells, and direct bilirubin in extracellular fluid were quantified after HepaRG cells were incubated with serum from rats injected with multiple components of YZH. Cellular uptake was determined by dynamic multiple reaction monitoring (DMRM) using LC-MS/MS. We found that the stable hyper-bilirubin HepaRG cell model could be established by incubating cells with 40 μg·mL-1 bilirubin and 50 μg·mL-1 probenecid. When the hyper-bilirubin cell model was incubated with serum from rats of YZH injection, there were 52.4% and 60.1% decrease in intercellular total bilirubin and indirect bilirubin, respectively, and 52.5% increase in extracellular direct bilirubin. Using DMRM mode, 53 components could be determined, and 8 potential bioactive candidates were identified from the serum. This method could be used to screen for bioactive metabolites of YZH. This strategy is simple, highly active, sensitive and specific, providing a new method for high throughput screening of therapeutic or toxic metabolites from traditional Chinese medicine. The regulations of Ethics Committee in the First Hospital of Lanzhou University were abided in the rat experiment of this study.
This study aimed to investigate the effect of Huangqin Tang (HQT) on oxidative stress associated with ulcerative colitis in rats, and to explore its antioxidant mechanism. After approved by Institute of Chinese Materia Medica Ethics Committees in China Academy of Chinese Medical Sciences, the rats were given 2, 4, 6-trinitrobenzenesulfonic (TNBS)/ethanol mixture to induce the ulcerative colitis (UC), and were randomly divided into normal group, model group, the salazosulfapyridine (SASP) group, and high, middle or low dose (20, 10, 5 g·kg-1) of HQT groups. After 5 days of treatment, the activity of catalase (CAT) from micrococcus lysodeikticus, glutathione peroxidase (GSH-px), myeloperoxidase (MPO), superoxide dismutase (SOD) were detected by biochemical assays. The levels of lipid peroxide (LPO) were detected by ELISA. The positive protein expression of nuclear factor erythroid-2-related factor 2 (Nrf2) were detected by immunohistochemistry method and the downstream antioxidant enzymes of Nrf2 were determined by Western blot analyses. The levels of SOD, CAT and GSH-px activities in the normal group were significantly higher than the model group, while the serum MPO activity in the model group was obviously increased (P < 0.05 or P < 0.01). Compared with the model group, there was a significant difference in the activity of CAT in the high and middle dose groups of HQT (P < 0.05 or P < 0.01), the activity of GSH-px in the high, middle and low dose groups of HQT were apparently higher than the model group (P < 0.05); The serum levels of LPO in the model group were significantly higher than those in the normal group (P < 0.05), while the up-regulating effects on LPO were reversed by the high and middle dose groups of HQT (P < 0.05). The expression of Nrf2 in the high-dose group of HQT and SASP group was statistically significant (P < 0.05). The results of Western blot showed that compared with the model group, each of the HQT and SASP group could increase the heme oxygenase (HO-1) and NAD[P]H:quinone oxidoreductase 1 (NQO-1) expression in a dose-dependence manner. HQT has significant anti-oxidative stress and obviously improves the signs, mental status and defecation of UC rats. The mechanism of action for HQT maybe related to activate the Nrf2 pathway and increase the expression of Ⅱ phase metabolic enzymes such as HO-1 and NQO-1, reduce the content of LPO and MPO in serum and enhance the activity of SOD, CAT and GSH-px.
The combination of ginkgo ketoester tablet-donepezil (GD) is a popular combination commonly used in clinic for the treatment of Alzheimer's disease. To evaluate the learning and memory improving ability of different proportions of the two drugs. We optimized the ratio of GD for treatment of dementia using a mouse model. Dementia was induced by multiple neuronal damages in mice. The experimental protocols were approved by the Animal Experimental Ethical Committee of Nanjing University of Chinese Medicine and all the procedures were strictly conducted in accordance with ethical principle of animal use and care. Morris water maze, brain hematosylin-eosin staining and the changes of the neurotransmitters and related enzymes in the plasma or brain tissues were tested to determine the effect of GD on dementia mice. The results showed that the dementia mice were significantly different from the normal group in terms of behavior, pathological sections and related indicators. Compared to the dementia mice, partial administration groups could improve learning and memory ability as well as indexes in the blood and brain tissues. Both the principal component analysis and multi-attribute comprehensive index methods were used to comprehensively evaluate the total effect of GD on anti-dementia. The results showed that the combination of two drugs at the dose of 0.5 to 1 times was in a dose-effect relationship, and the dose of 1 (the clinical equivalent) had the best treatment effect. Then based on the optimal dose, GD 1:1 had best effect, which was consistent with the clinical use of two drugs. This provides scientific basis for more effective application of the compatibility between ketoester tablet and donepezil for modern clinic medicine.
To investigate the effect of Sishen Wan (SSW) on intestinal flora in diarrhea-predominant irritable bowel syndrome (IBS-D) rats and explore the efficacy of this regiment for improving IBS-D, we divided 45 SPF male SD rats randomly into control, disease, SSW, Ershen Wan (ESW) and Wuweizasan (WWZS) groups. The spleen-kidney-yang deficiency type IBS-D rat model was prepared by a composite factor and administered for 14 days. After collecting the feces of the rats, total DNA was extracted from the stool samples. Primers were designed based on the 16S r RNA V3 to V4 regions of the bacteria, and used for high-throughput sequencing with the Illumina Miseq platform. We found that SSW can effectively reduce the diarrhea index (P < 0.05) and reduce the high sensitivity of intestinal tract (P < 0.05) of IBS-D rats. The principal component analysis (PCA), principal co-ordinates analysis (PCoA) and non-metric multidimensional scale analysis (NMDS) based on the Beta diversity distance showed that there were significant differences in the composition of the gut microbiota among the five groups (P < 0.05). The disease group has the lowest in abundance, uniformity and diversity of gut microbiota. Compared with the control group, the disease group showed a significant increase in Proteobacteria, Actinobacteria, Veillonococcus and Mycoplasma (P < 0.05), but a significant reduction in Pleaverella (P < 0.05). Compared with the disease group, SSW administration caused significant reduction in the Proteobacteria and Mycoplasma (P < 0.05), but significant increases of Clostridium, Turicibacter and Romboutsia (P < 0.05). Our study shows that SSW has the potential as a therapeutic regiment for treatment of IBS-D due to partial regulation of the intestinal flora. In addition, there is a synergy between ESW and WWZS.
Using the idiosyncratic lipopolysaccharide (LPS)-mediated hepatotoxicity model as a positive control, liver injury induced by Cortex Dictamni aqueous extract (AE) or Cortex Dictamni ethanol extracts (EE) was evaluated. Idiosyncratic hepatotoxicity model was established in rats[Institutional Animal Care and Use Committee (IACUC)-2018-008] by injecting LPS at a dosage of 2.8 mg·kg-1. Rats were randomly divided into 10 groups. The plasma levels of liver function biomarkers such as alanine transaminase (ALT), aspartate aminotransferase (AST) were measured. Histological changes (HE staining), hepatocellular apoptosis and the content of cytokines of liver were measured. Network pharmacology was used to analyze the relationship between chemical components and immunity in Cortex Dictamni. Compared with the control group, the doses (25, 50 g·kg-1) of AE or EE had no significant changes in ALT, AST and liver pathology (P>0.05). The doses of 4.2 g·kg-1 of AE or EE+LPS groups exhibited an elevation in ALT, AST and serum cytokines (P < 0.01). Disorder of liver lobular arrangement and irregular island-like or massive necrosis of liver cells were observed in these groups. Network pharmacology shows that Cortex Dictamni may directly or indirectly participate in the process of immunomodulation. We found that Cortex Dictamni regulated 15 core targets and affected 19 pathways, including apoptosis, TNF-α, NF-kappa B signaling pathways. These results suggest that Cortex Dictamni can induce idiosyncratic hepatotoxicity and the water extract can induce more serious liver injury then ethanol extract of Cortex Dictamni. These findings provide a reference for elucidating the idiosyncratic hepatotoxicity induced by Cortex Dictamni.
To expand an efficient strategy for the conversion of antibacterial activity of fluoroquinolones into an antitumor activity, sixteen new compounds, 1-cyclopropyl-6-fluoro-7-(4-methyl-piperazin-1-yl)-3-(5-arylidene-thiazol-4(5H)-one-2-yl)-quinolon-4(1H)-ones (7a-7p), were designed and synthesized with a thiazolone ring and an arylidene moiety as an isostere and modified group, respectively, from ciprofloxacin. Their structures were characterized by elemental analysis and spectral data. The in vitro antitumor activity of the synthesized compounds were measured using Hep-3B, Capan-1 and HL60 cell lines and were found to be more potent than ciprofloxacin. Meanwhile, the SAR revealed that the halogenated phenyl compounds such as fluorophenyl (7h, 7i), chlorophenyl (7j, 7k) or bromophenyl compounds (7l, 7m), and aromatic heterocyclic substitution such as furyl (6n) or pyridyl compounds (6o, 6p) displayed better activity than the control compounds, especially the IC50 values of pyridyl compounds 6o and 6p against Capan-1 cell growth was comparable to doxorubicin. Thus, an arylidene-modified thiazolone scaffold as the replacement of the C-3 carboxylic acid group appears to be an alternative route for an improved antitumor activity of fluoroquinolones.
The chemical constituents of Litsea coreana were investigated using chromatographic methods, including column chromatography on silica gel, MCI, and semi-preparation HPLC. Two compounds were isolated and identified as hawktealignan A (1) and cinnamophilin (2) by NMR analyses as well as their physical and chemical properties. Compound 1 is a new lignan and compound 2 was isolated from this plant for the first time.
A LC-MS/MS method for quantification of norfloxacin in human plasma had been developed. This method was applied to the pharmacokinetics study of norfloxacin in the human. The plasma sample was precipitated by methanol and ciprofloxacin was used as the internal standard (IS). Chromatographic separation was performed on a Symmetry® C18 column(100 mm×4.6 mm, 5 μm). Mobile phase contains 0.3% formic acid and 5% methanol in deionized water at a flow rate of 0.45 mL·min-1. Norfloxacin and ciprofloxacin (IS) were ionized with an ESI source and operated in positive ion mode. The detected ions were m/z 320.3→302.1 (norfloxacin), m/z 332.3→314.1 (ciprofloxacin). This LC-MS/MS method yielded a linearity over the range of 10-1 000 ng·mL-1 with the lower limit of quantitation (LLOQ) of 10 ng·mL-1. The intra and inter-assay precisions (RSD%) were within the range of 2.64%-7.23% and the accuracy (RE%) was less than ±5.00%. The pharmacokinetic parameters tmax, Cmax, AUC0-t, and t1/2 were 1.28±0.364 h, 627±171 ng·mL-1, 2 938±850 h·ng·mL-1, and 6.01±1.36 h, respectively. This LC-MS/MS method was proven simple, sensitive, rapid and suitable for pharmacokinetics study of norfloxacin in the human and Approved by the Medical Ethics Committee of Liuzhou Workers' Hospital.
Danhong injection (DHI) and ceftriaxone sodium were used in combination based on their experimental uses in clinic. This study was designed to investigate the impact of ceftriaxone on pharmacokinetics and pharmacodynamics of the phenolic acids from DHI. After administration of DHI for 7 d, ceftriaxone (CFTX) was combined with DHI for the next 7 d in adult male Sprague-Dawley (SD) rats. All the drugs were administered through caudal vein. UHPLC-TQ-MS was applied in determining the plasma concentration of p-coumaric acid (p-CA), salvianolic acid D (SaD), rosmarinic acid (RA) and salvianolic acid B (SaB). The pharmacokinetic parameters of the combination group or the Danhong injection alone group were calculated by statistical moment method, Cmax and the average of the area under the curve AUC0-t using 90% confidence interval of the bioequivalence and bioavailability degree module in DAS 3.2.8 statistic software. The results showed that Cmax of p-CA, SaD, RA and SaB were unqualified within 90% confidence intervals for bioequivalence statistics. And the results showed that AUC0-t of SaD, RA and SaB within 90% confidence intervals for bioequivalence statistics were unqualified. There were no significant difference in the tmax (P>0.05). The results of anticoagulation in vivo showed that the international normalized ratio (INR), prothrombin time (PT), thrombin time (TT) and activated partial thromboplastin time (APTT) were significantly increased when combined with CFTX (P < 0.05 or P < 0.01). The results in antithrombotic effects revealed that the thromboxane B2 (TXB2) level in serum was significantly decreased (P < 0.01) in the combination group compared with Danhong injection alone. However, there was no significant difference in antiplatelet effects. These results suggest that CFTX may enhance the anticoagulation and antithrombotic effects of DHI through altering pharmacokinetics and pharmacodynamics in SD rats.
In this paper, three methods, differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and X-ray powder diffraction (PXRD), were used to characterize the structure of Palbociclib. The form-B crystal mixed in with form-A crystal, the effective form of Palbociclib, was quantitated by the single peak method (peak area method and peak height method) using X-ray powder diffraction. While the qualitative identification by DSC was not clear, SEM and PXRD quickly and effectively identified two types of crystal. The standard curve equations established by the peak area method and the peak height method are:y=0.842 75x-0.001 21 and y=0.909 64x-0.002 32. This suggests that the linear relationship of peak area method is better than that of peak height method (R2=0.986 17 and R2=0.985 83). The sensitivity of the peak area method (LOD=1.17%, LOQ=3.92%) are higher than the peak height method (LOD=1.19%, LOQ=3.97%). The methods from this study can be used to identify and quantify palbociclib form-A and form-B crystal rapidly.
The study was conducted to characterize the pharmacokinetics, distribution, metabolism and excretion of CHMFL-FLT3-122 after a single oral dose of 50 mg·kg-1[14C] labeled CHMFL-FLT3-122 in rats. Isotope tracing techniques were used to analyze drug concentration and identify the distribution of drugs in tissues and metabolites in biological samples. The experiments were approved by the Animal Ethics Committee of XenoBiotic Laboratories-China, Inc. The absolute bioavailability in male and female rats were 45.83% and 50.92% respectively. The parent drug and its metabolites were extensively distributed in the stomach, intestine, liver and lung, and were eliminated completely in 48 h. The majority of radioactivity was excreted through the feces at 92.34% of the dose with a small fraction through urine at 3.99% of the dose. The parent drug was the most significant circulating component, representing 49.23% and 70.65% over the 0-48 h collection time interval in the plasma of male and female. Two major metabolites, M553 (sulfate conjugate) and M457 (N-dealkyl product), were identified in plasma. Metabolites of CHMFL-FLT3-122, including ten phase Ⅰ and four phase Ⅱ metabolites, were identified. The metabolic pathways of CHMFL-FLT3-122 were proposed as N-dealkylation, oxidation, amide hydrolysis, sulfate conjugation, and glucuronic conjugation.
This study explores the antidepressant mechanism of Radix Bupleuri-Radix Paeoniae Alba herb pair and the core role in Xiaoyaosan. The behavioral indicators were used to observe the effects of herb pair, Xiaoyaosan, and a negative control (Xiaoyaosan remove Radix Bupleuri-Radix Paeoniae Alba) on CUMS rats. The body weight, number of crossing and rearing, sugar preference rate were significantly decreased (P < 0.001) and the immobility time of forced swimming test was significantly prolonged (P < 0.01) in the model group. Radix Bupleuri-Radix Paeoniae Alba herb pair has significant antidepressant effect, with the number of crossing in low dose group similar to Xiaoyaosan, while the number of rearing and the sucrose preference rate in high dose group are equivalent to Xiaoyaosan, and the immobility time in high and low-doses group are better than Xiaoyaosan. Animal experimentation was approved according to the Committee on the Ethics of Animal Experiments of Shanxi University. Metabonomics results showed 15 biomarkers related to depression, whereas administering Xiaoyaosan or the herb pair can ameliorate 12 or 8 metabolites respectively, compared to the negative control, which can only ameliorate 6 metabolites. The metabolic pathway analysis showed 5 depression-related pathways. The herb pair and Xiaoyaosan exerted antidepressant effects through common 4 metabolic pathways, while the negative control only exerted effects through 3. In summary, behavioral, metabolomics and metabolic pathway analysis revealed that Radix Bupleuri-Radix Paeoniae Alba plays an important role in the biological effect of Xiaoyaosan.
In this study, black phosphorus quantum dots (BPQDs)-loaded liposomes (liposome-BPQDs) were prepared to explore physicochemical properties and photothermal effects on cervical cancer cells. BPQDs were fabricated by ultrasonic method. Liposome-BPQDs were prepared by thin film dispersion. Surface morphology, particle size, zeta potential and Raman spectra of liposome-BPQDs were characterized. The cytotoxicity of the liposome-BPQDs against human cervical cancer cells (HeLa) was examined by CCK-8 assay. Confocal laser scanning microscope (CLSM) and fluorescence microscopy were used to observe the uptake and apoptosis of HeLa cells. The results indicated that liposome-BPQDs were ellipsoidal or spherical under scanning electron microscope, TEM observation showed liposome-BPQDs were about 90-110 nm in diameter. The particle size measurements showed liposome-BPQDs were (104.2±0.35) nm in diameter, and zeta potential were examined to be (-11.3±3.01) mV. The encapsulation efficiency was (84.40±2.13)%.Under natural conditions with outdoor ventilation, temperature range of 25℃-34℃ and relative humidity of 80%-82%, the photothermal effects of liposome-BPQDs was better and the degradation denaturation of liposome-BPQDs were slower than those of BPQDs. The results also reflected that liposome-BPQDs could be uptaken by HeLa cells easily. After near-infrared laser irradiation, the mortality of HeLa cells rise significantly when the amount of BPQDs reach 20 μg·mL-1. In summary, liposome-BPQDs with high stability exhibited good photothermal effects, which can be expected to be applied to photothermal therapy of cervical carcinoma.
Ellagic acid is ubiquitous in plants and is considered as a potential candidate for antioxidant and antineoplastic drugs. However, ellagic acid has poor solubility and precipitates easily even after initial solubilization. Improvement of its bioavailability has been a concern of pharmaceutical industry. It was found that storage in Sanlejiang oral liquid at low temperature keeps its stability. Ellagic acid is anomalous in a way that is easily soluble at low temperatures but precipitates at high temperatures. In order to reveal the mechanism of this phenomenon and develop precipitation prevention and control strategies, ellagic acid in Sanlejiang oral liquid was stored at high, medium and low temperatures for three months. The changes of composition and phase state of the whole system during storage were systematically tracked and studied by means of precipitation amount or morphology, HPLC chemical profile of supernatant versus precipitates, and comprehensive characterization of physical phase state. The results show that the amount of precipitation at low temperature is only 1/3 of that at normal room temperature. As the temperature rises, the sedimentation increases sharply. HPLC analyses of supernatant versus precipitates revealed that ellagic acid precipitation originated from two ways:chemical degradation and physical deposition. The chemical sedimentation is related to the hydrolysis of tannins under acidic condition, forming chebulagic acid and corilagin. Physical sedimentation is related to the decrease of the association degree and viscosity of polyphenol colloids when temperature rises. This study elucidated the stability mechanism of ellagic acid in liquid preparations of TCM, and provided the mechanistic basis for efficient utilization and solution prepartion of ellagic acid.
The molecular identification of Ophiocordyceps sinensis and its adulterants was carried out by real-time fluorescent PCR with TaqMan probe. Genomic DNA was extracted from 100 samples of Ophiocordyceps sinensis and its adulterants. MEGA 7.0 software was used for comparative analysis to define the variable sites between Ophiocordyceps sinensis and its adulterants according to the internal transcribed spacer (ITS) region of ribosomal DNA (rDNA). A set of specific primers and TaqMan probe were designed using Primer Premier 6.0 software, and sensitivity and specificity studies were performed on two different real-time fluorescent PCR systems (Genesig q16 and Bio-Rad CFX96). The sensitivity study showed that the detectable DNA template concentration of Ophiocordyceps sinensis for the real-time fluorescent PCR was 0.016 ng·μL-1 in the Bio-Rad CFX96 system and 15.527 ng·μL-1 in the Genesig q16 system, respectively. Meanwhile, this method had good specificity for Ophiocordyceps sinensis on Genesig q16 and Bio-Rad CFX96 systems, so Ophiocordyceps sinensis could be clearly distinguished from Ophiocordyceps nutans, Cordyceps gunnii, Cordyceps militaris, Cordyceps cicadae, Cordyceps liangshanensis, Cordyceps gracilis. Our results indicate that real-time fluorescent PCR with TaqMan probe can be used to accurately identify Ophiocordyceps sinensis from its adulterants. This provides a technical method that has wide applications for market management and quality control of Chinese materia medica.