Latest ArticlesTo 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.
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).
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.
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.
The binding of small molecule drugs to targets is mostly through non-covalent bonds, and hydrogen bond, electrostatic, hydrophobic and van der Waals interactions function to maintain the binding force. The more these binding factors lead to strong bindings and high activities. However, it is often accompanied by the increase of molecular size, resulting in pharmacokinetic problems such as membrane penetration and absorption, as well as metabolism, which ultimately affects the drug success. Fragment-based drug discovery (FBDD) is to screen high-quality fragment library to find hits. Combine with structural biology, FBDD generates lead compounds by means of fragment growth, linking and fusion, and finally drug candidates by the optimization operation. During the value chain FBDD is closely related to structure-based drug discovery (SBDD). In this paper, the principle of FBDD is briefly described by several launched drugs.
The exploration of drug toxicity and mechanisms is a vital component in ensuring the safe use of drugs in clinical practice, as this topic has attracted widespread concern. The intestinal flora holds great significance for drug metabolism, efficacy and mechanism, and is an instrumental metabolic organ that facilitates material information transfer and biotransformation. However, an increasing number of studies have shown that intestinal bacteria are closely related to the toxicity of specific drugs. On the one hand, drugs are transformed into toxic metabolites under the influence of intestinal bacteria, thus inducing direct drug toxicity. On the other hand, the composition and function of the intestinal flora are altered under drug influence, resulting in disruption of endogenous metabolic pathways. Consequently, this disruption compromises the intestinal barrier and affects other organs, leading to indirect drug toxicity. This review meticulously compiles recent examples of drug toxicity attributed to intestinal bacteria, explores in depth the contention that metabolic enzymes of gut microbiota may be of great influence on oral drug toxicity, and outlines prospective avenues for future research on gut microbiota and drug toxicity and mechanisms. This not only provides novel perspectives for the judicious clinical utilization of drugs but also offers insights for the safety assessment of innovative pharmaceuticals.
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.
Alternative splicing of pre-messenger RNA (pre-mRNA) is a crucial mechanism for the diversity of the human transcriptome and proteome. Alternative splicing is a complex gene regulation process. Whole-transcriptome analysis shows that 95% of human exonic genes are alternatively spliced, involving various cis-acting elements and trans-acting factors. Any changes in any component or step may cause erroneous splicing events and lead to the occurrence of various related diseases. In addition to gene replacement therapy that directly changes the splicing results, RNA splicing modification is expected to become a new therapeutic strategy to alleviate or treat diseases by targeting and correcting abnormal pre-mRNA splicing. Splicing modification tools currently developed including RNA trans-splicing, antisense oligonucleotides, small interfering RNA, and small molecule drugs can correct abnormal splicing through different ways. This article reviews the resent progress of epigenetic regulation of pre-mRNA alternative splicing in recent years, and discusses the occurrence and regulation of alternative splicing, the types of diseases caused by related splicing defects, and the current-used tools for targeting and altering splicing. The importance of splicing modification strategies in the future treatment of human diseases is envisioned.
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.
Three new anthraquinones were isolated from the 80% ethanol extract of Prismatomeris tetrandra by silica gel, MCI, ODS column chromatography and high performance preparative liquid chromatography (HPLC). The structures of the new compounds were identified by mass spectrometry, nuclear magnetic resonance and other spectroscopic methods as 6-hydroxy-1,2,3-trimethoxy-7-methylanthracene-9,10-dione (1), 6-(hydroxymethyl)-1,2,3-trimethoxyanthracene-9,10-dione (2) and 7-hydroxy-6-(hydroxymethyl)-1,2-dimethoxyanthracene-9,10-dione (3). Compounds 1, 2 and 3 showed protective effects against monosodium glutamate-induced damage in SH-SY5Y neuroblastoma cells, with the cell survival rates elevated 18.45%, 4.31%, and 7.65%, respectively.