Latest ArticlesThe natural products containing 3-acyl tetramic acid units have a large number of complex and diverse structures, showing a variety of biological activities such as antibacterial, antiviral, anti-tumor and so on, especially antibacterial activity which are regarded as a potential reservoir of new antibiotics. In this paper, the antibacterial activities of various natural products containing 3-acyl tetramic acids and the new research hotspots and directions are reviewed.
Compared with other drug-resistant strains, Acinetobacter baumannii has the characteristics of serious drug resistance, high mortality and difficulty to treat. As the phenomena of resistance to existing anti-Acinetobacter baumannii drugs continuously occurs, the development of new anti-Acinetobacter baumannii drugs is urgent. This review introduces the clinical application and research progress of anti-Acinetobacter baumannii drugs, aiming to provide help for the research and development of anti-Acinetobacter baumannii drugs.
Quantitative nuclear magnetic resonance (qNMR) technology has significant advantages in quantification due to its simple sample processing and high reproducibility. Two-dimensional qNMR analysis, which can solve the quantification problem of different components in complex systems, has gradually been applied in medicine, food, metabonomics, chemical engineering, and other fields. This paper reviews the analysis methods, influencing factors, experimental optimization, application fields, and other aspects of qNMR to promote its wide and effective application.
This study assessed and explored the pharmacological effects and mechanisms of action of IMMH002 {2-amino-2-(2-(4ʹ-(2-ethyloxazol-4-yl)-[1, 1ʹ-biphenyl]-4-yl)ethyl)propane-1, 3-dio}, a selective sphingosine-1-phosphate receptor subtype 1 (S1P1) modulator, in a concanavalin A (ConA)-induced autoimmune hepatitis (AIH) mouse model. The experimental protocol strictly adhered to the guidelines of the Ethics Committee for Animal Research of the Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College (Approval No.: 00004046). Male ICR mice were pre-treated with the drug for four days, followed by induction of AIH through tail vein injection of ConA protein. Liver function, hepatic tissue pathology, peripheral blood parameters, as well as immunoglobulin G (IgG), inflammatory cytokines, T cell distribution, and inflammatory pathways were evaluated in mice. Results demonstrated that IMMH002 significantly reduced liver function indicators such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST), alleviated hepatic tissue inflammation and necrotic damage, decreased serum IgG levels, and lowered the expression of inflammatory mediators including interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and interferon γ (IFN-γ). Additionally, it facilitated T lymphocyte homing, downregulated the phosphorylation of nuclear factor kappa-B (NF-κB), IκB kinase β (IKKβ) and nuclear factor inhibitor protein-α (IκBα) proteins in hepatic tissue and cellular inflammation models. Collectively, IMMH002 effectively ameliorated ConA-induced autoimmune hepatitis in mice, exhibiting extensive anti-inflammatory and anti-necrotic effects, thereby laying a theoretical foundation for AIH clinical treatment.
To investigate the effects and mechanism of the combination of Morus alba L. (Sangzhi) alkaloids(SZ-A) and metformin (Met) on glucose metabolism in type 2 diabetic mice, KKAy mice were divided into four groups according to the glucose and lipid indexes: control group (control), Morus alba L. (Sangzhi) alkaloids group (SZ-A, 100 mg·kg-1), metformin group (Met, 100 mg·kg-1) and combined administration group (combination, Comb, 100 mg·kg-1 SZ-A + 100 mg·kg-1 Met). All groups were administered by gavage once daily for 7 weeks accompanied with monitoring food intake, water intake, body weight as well as glycemia. Additionally, oral glucose tolerance test (OGTT), insulin tolerance test (ITT) and oral sodium pyruvate tolerance test (OPTT) were performed at week 2, week 5, week 6, respectively. The experiments were approved by the Institutional Animal Care and Use Committee of the Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College (00004332). We determined the weight and lipid content of liver, and then performed the histopathological analysis after sacrificed. Furthermore, Western blot assay was used to detect the protein levels of key molecules of PI3K/PDK1/Akt/GLUT signaling pathway in liver, muscle and adipose tissue. Compared to the SZ-A or Met monotherapy group, SZ-A + Met significantly improved the glucose metabolism disorder, which was showed in reduced food intake, water intake, the level of fasting blood glucose, postprandial blood glucose and glycosylated hemoglobin A1c (HbA1c) of KKAy mice, as well as improved glucose tolerance, enhanced insulin sensitivity and inhibited gluconeogenesis. In addition, SZ-A + Met obviously up-regulated the protein expression levels in PI3K/PDK1/Akt/GLUT signaling pathway in liver, muscle and adipose tissue of KKAy mice. Moreover, the liver lipid accumulation and blood aminotransferase level of KKAy mice in the combined administration group were significantly reduced. Therefore, we concluded that the combination of SZ-A and Met improved glucose metabolism and inhibited the occurrence and development of T2DM via promoting glucose uptake and utilization, suggesting that the combination of SZ-A and Met is a more useful treatment for T2DM.
GJ-4 is crocin enrichments extracted from Gardenia jasminoides J. Ellis, and our previous studies have shown that GJ-4 significantly improved learning and memory impairment induced by Aβ in mice. Herein, a memory deficit model was developed by injecting okadaic acid (OA) into the lateral ventricle of mice, and the neuroprotection and underlying mechanism of GJ-4 on neuronal injury caused by Tau hyperphosphorylation were investigated. The Animal Care & Welfare Committee, Institute of Materia Medica, CAMS & PUMC has approved all procedures (No.00000318). GJ-4 at different doses was intragastric administration to mice for 16 days. Step-down test and Morris water maze test showed that GJ-4 could significantly improve OA-induced memory impairment in mice, and reduced the loss of Nissl bodies in the hippocampus of mice. GJ-4 could also decrease the phosphorylation level of Tau protein at Ser396, Thr231 and Ser404 via increasing protein phosphatase 2A (PP2A) activity and inhibiting glycogen synthase kinase-3β (GSK-3β) activity. Besides, further researches indicated that GJ-4 could inhibit the level of oxidative stress in the brain of OA mice, reduce neuronal apoptosis and inhibit the neuroinflammation mediated by activation of astrocytes in the hippocampus of mice, and eventually achieve its effects in improving learning and memory impairment in mice. According to these findings, we anticipated that GJ-4 might be a potential therapeutic drug for Alzheimer's disease.
Gut microbial metabolite trimethylamine-N-oxide (TMAO) is associated with type 2 diabetes (T2DM). Decreased insulin sensitivity is a significant etiological factor of T2DM. Adipocytes, myocytes, and hepatocytes are the three major target cells for insulin. This study aims to investigate the effects and mechanisms of TMAO on the insulin sensitivity of these target cells. Research results indicate that in different ages of db/db diabetic mice, plasma TMAO levels were increased. TMAO significantly inhibits the insulin signaling pathways in these three major insulin target cells, reduces glucose uptake in 3T3-L1 adipocytes and L6 myocytes and downregulates genes related to gluconeogenesis in primary mouse hepatocytes. Furthermore, in mice with normal insulin sensitivity, elevating plasma TMAO levels to those seen in db/db mice using a minipump results in impaired glucose tolerance and hyperinsulinemia. All animal experiments were carried out with approval of the Experimental Animal Welfare Ethics Committee of the Institute of Materia Medica (Chinese Academy of Medical Sciences and Peking Union Medical College). Mechanistic studies suggest that TMAO exposure increases the levels of endoplasmic reticulum stress-related proteins in these three major insulin target cells. In summary, TMAO directly attenuates insulin sensitivity in insulin target cells, and its mechanism of action may involve enhancing endoplasmic reticulum stress.
A pharmacophore-based study was conducted to investigate the therapeutic activity of the traditional Tibetan medicine Zha Xun (ZX) in liver diseases. In the present study, the protective effect of ZX on the acute liver injury induced by concanavalin A (ConA) and 0.15% carbon tetrachloride (0.15% CCl4) in ICR mice was evaluated, and the results showed that ZX significantly reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the ConA-induced acute immune liver injury model and the CCl4-induced acute oxidative liver injury model (P < 0.05). Subsequently, the protective effects of aqueous, 95% ethanol, 60% ethanol and 30% ethanol eluting fractions of ZX, and fulvic acid, the main water-soluble constituent of ZX, were evaluated against acute oxidative liver injury induced by 0.15% CCl4 in mice. The results showed that different solvent-eluting fractions of ZX showed certain hepatoprotective activities, among which the aqueous extract of ZX and 30% ethanol extract of ZX significantly reduced the serum levels of ALT, AST, and lactate dehydrogenase (LDH) in mice (P < 0.05), and the serum levels of LDH in mice were significantly reduced by fulvic acid (P < 0.05), which showed significant hepatoprotective activity. The protective activities and preliminary mechanisms of the total extract of ZX, the aqueous extract of ZX, the 30% ethanol extract of ZX, and fulvic acid against hepatocellular injury in vitro were further evaluated by using the H2O2-induced hepatocellular injury model. The results showed that the components could significantly inhibit H2O2-induced hepatocellular injury, reduce the levels of ALT, alkaline phosphatase (ALP), and LDH, improve the survival rate of hepatocellular cells, and reduce the content of intracellular reactive oxygen species (ROS) in cell culture. At the same time, it can inhibit hepatocyte apoptosis by increasing the expression ratio of Bcl-2/BAX protein and decreasing the expression ratio of cleaved caspase-3/pro caspase-3 protein. The present study showed that ZX has clear hepatoprotective activity in vitro and in vivo, and the different solvent elution fractions of ZX showed certain hepatoprotective activity, among which the aqueous extract of ZX, 30% ethanol extract of ZX had better hepatoprotective activity, and the activity of 60% ethanol extract of ZX was stronger than that of 95% ethanol extract of ZX. The activity of ZX and its water-soluble elution site exerted hepatoprotective effects by inhibiting hepatocyte apoptosis and oxidative stress. The animals used in this experiment and related disposal meet the requirements of animal welfare, and have been reviewed and approved by the Laboratory Animal Management and Use Committee of the Institute of Materia Medica, Chinese Academy of Medical Sciences (approval number: 00004018).
Atopic dermatitis (AD) is a chronic, relapsing, inflammatory dermatosis with a variety of clinical manifestations and difficult to cure. Currently, many AD drug candidates have entered the research and development pipeline. In order to provide technical specifications for the clinical development of AD drugs, the Center for Drug Evaluation of National Medical Products Administration released the "Technical Guidelines for Clinical Trials of Drugs for AD Treatment" (Draft for Comments) in November 2022. Non-clinical pharmacodynamics evaluation is an important research before the drug enters clinical trials. Oxazolone (OXA)- and 2, 4-dinitro-fluorobenzene (DNFB)-induced models are the most popular classical hapten-induced AD murine models, but variations of modeling are existing in the methods from different studies, including sensitization sites, haptens' dosages, the period of challenges, and the skin lesions severity evaluation as well. In this study, the investigation of OXA- and DNFB-induced AD murine models with various conditions of modeling was performed to compare the characteristics of hapten-induced AD murine models in the pathological process and severity according to the appearance of AD patients, and the guidance of pharmacodynamics evaluation of AD-therapeutic drugs in clinical trials as well, which may provide a proposal for AD treatment drug candidates in the non-clinical pharmacodynamics evaluation. All animal experiments were approved by the Animal Care & Welfare Committee of Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College (approval No.: 00007782 and 00007784).
To study the cognitive effects of diterpene ginkgolides (DG), transient middle cerebral artery occlusion (tMCAO)-induced rats were established. tMCAO-rats induced by suture method were divided into sham operation group, solvent control group, NBP group, DG group. The animal experiments in the present study were performed in accordance with the Ethical Guidelines of the Laboratory Animal Welfare Ethical Committee of Peking Union Medical College (00000646, 00000635). The effects of DG on tMCAO rats were evaluated by neurological severity score, cerebral infarction volume measurement, step-down and Morris water maze test. In the acute tMCAO rat model, 100 mg·kg-1 DG improved the neural score and infarction volume. In the chronic tMCAO rat model, DG 100 mg·kg-1 significantly improved the survival rate of tMCAO-induced rats. The Morris water maze results showed 100 mg·kg-1 DG decreased the latency of tMCAO-induced rats to find the platform, while the effect was weaker than the NBP. However, DG 30 mg·kg-1 did not show a significant effect. In conclusion, DG exerted a therapeutic effect on transient middle cerebral artery occlusion.