Latest ArticlesZ-VAD-FMK was combined with hypoxia-reoxygenation (H/R) injury to establish a necroptosis model of H9c2 cells to mimic the pathological changes of myocardial ischemia reperfusion injury (MIRI) in vitro and to study the effect and mechanism of tilianin against myocardial ischemia-reperfusion injury. A cell counting kit-8 (CCK-8) was used to detect cell viability, and commercial kits were used to detect lactate dehydrogenase (LDH) and superoxide dismutase (SOD) in the cell culture supernatant. Hoechst 33342/PI immunofluorescence staining was used to detect cell death. DCFH-DA, BBcellProbeTMM61, and JC-1 probes were used to detect reactive oxygen species (ROS), mitochondrial permeability transition pore (mPTP), and mitochondrial membrane potential (MMP), respectively. An enzyme-linked immunosorbent assay (ELISA) method was used to detect the release of tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6). The results show that the cell viability, SOD activity, and MMP of the model group induced by H/R injury decreased, as compared with control group, but the necroptosis rate, LDH level, and ROS release increased significantly. Furthermore, mPTP of the model group cells opened, and TNF-α, IL-1β, and IL-6 levels were significantly higher. Molecular docking modeling showed that tilianin can bind to calmodulin-dependent protein kinase Ⅱ (CaMKII), and Western blot results showed that compared with control group, the expression levels of p-CaMKII and phospho-mixed lineage kinase domain-like protein increased in the model group, and tilianin could decrease the expression level of these proteins. The above results indicate that tilianin can protect H9c2 cells by inhibiting the phosphorylation of CaMKII at threonine 287, protecting mitochondrial function, and inhibiting the opening of mPTP to prevent necroptosis. This study has value for research on new methods to treat H/R injury.
Hepatic encephalopathy is a common metabolic neuropsychiatric syndrome in the development of end-stage liver disease. Since the concept of intestinal-liver-brain axis was proposed, the relationship between the pathogenesis of hepatic encephalopathy and the gut microbiota has been a hot research topic. In recent years, studies have confirmed that gut microbiota is involved in and affects various pathological processes of hepatic encephalopathy. This article combines the latest research progress at home and abroad to elaborate on the research status of regulating gut microbiota and thus interfering with the pathological process of hepatic encephalopathy, hoping to provide new ideas and methods for the intervention of hepatic encephalopathy based on the regulation of gut microbiota.
Acetaminophen (APAP, also known as paracetamol)-induced liver injury is the leading cause of drug-induced liver injury in the world. Wuzhi Tablet (WZ, an ethanol extract of Schisandra sphenanthera) is widely used in clinical practice to protect liver function. Our previous studies have shown that pretreatment with WZ for 3 days can significantly protect against APAP-induced liver injury; however, the effect of different intervals between APAP and WZ treatment on APAP-induced liver injury remains unclear. In this study, the change in liver injury indexes, APAP metabolites, and the activity of cytochrome P450 (CYP450) enzymes after treatment with WZ and APAP at different intervals were determined. The animal experiment was reviewed and approved by the Animal Ethics Committee of Sun Yat-sen University. The results show that 0 h, 0.5 h, and 2 h pretreatment with WZ significantly protected against APAP-induced liver injury in mice, as evidenced by a significant decrease in biochemical parameters such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), and malonaldehyde (MDA). WZ inhibited the metabolic activation of APAP mediated by CYP450 enzymes and reduced the formation of APAP metabolites. This study further demonstrates that pretreatment with WZ at different intervals (0 h, 0.5 h, and 2 h before APAP dosing) exerts a significant hepatoprotective effect against APAP-induced liver injury, and a single-dose of WZ inhibits the activity of CYP450 enzymes related to APAP metabolic activation, thereby protecting against APAP-induced hepatotoxicity.
Using a H2O2-induced BRL cell senescence model, we investigated the anti-aging effects of drug-containing serums of Erzhi Wan (EZW) and various polar extracts (petroleum ether, ethyl acetate, n-butanol, water, and iridoid glycoside-enriched fractions). Cell viability was detected by MTT assay. Cell senescence was evaluated with β-galactosidase staining assay. Intracellular reactive oxygen species (ROS) were measured by flow cytometry. UFLC-Q-TOF-MS/MS was used to identify chemical components in EZW and the extracts, and molecular docking technology was used to predict the anti-aging components of EZW. Results showed that treatment of cells with 600 μmol·L-1 H2O2 for 72 h markedly induced cell senescence, inhibited cell proliferation and increased intracellular β-galactosidase activity and ROS levels. If cells were pretreated with drug-containing serum of EZW this induction of senescence was decreased. A total of 49 chemical compounds were identified in EZW by liquid chromatography-mass spectrometry, 14 of these were identified by molecular docking as potential active ingredients. Based on these analyses, and the in vitro experiments with polar extracts, we conclude that the anti-aging components of EZW are triterpenes, flavonoids and phenyl alcohols, providing a basis for further elucidation of the active agents and mechanism of the anti-aging effect of EZW.
The structure and diversity of the intestinal flora in rats exposed to high altitude hypoxia was investigated. Animal experiments strictly follow the regulations of Medical Laboratory Animal Ethics Committee of Qinghai University, School of Medicine. SD rats were randomly divided into a control group, a moderate altitude hypoxia group, and a high altitude hypoxia group. The pH value of the feces was measured and histopathological changes in the small intestine were determined by HE staining, and the intestinal flora were characterized by 16S rDNA high throughput sequencing technology on the 3rd, 7th, 15th, and 30th day of hypoxia exposure. Compared with the control group, the fecal pH value of rats in the moderate altitude hypoxia group and the high altitude hypoxia group was decreased significantly. The lamina propria and submucosa capillaries were slightly dilated and congested on the 3rd day in the moderate altitude hypoxia group. In the high altitude hypoxia group the submembrane capillaries were dilated and congested, the lamina propria of the mucosa showed mild edema, and the lymphatic vessels were dilated on the 7th day. The composition and diversity of intestinal flora in these rats changed significantly with prolonged exposure to the high altitude hypoxic environment. A total of 35 phyla, 87 classes, 205 orders, 337 families, 638 genera, and 256 species were annotated in the three groups of rats, including Firmicutes, Clostridia, Clostridiales, Ruminococcaceae, Akkermansia, and Lactobacillus_murinus. Compared with the control group, the intestinal flora of the hypoxic groups showed the most significant changes by the 15th day. There were 9 microbiota of gut microorganisms with relative abundance in the moderate altitude hypoxia group, of which Rikenellaceae_RC9_gut_group bacteria was the most common, there were 19 different microbiota of gut microorganisms with higher relative abundance in the high altitude hypoxia group, of which Ruminococcaceae bacteria was the most common. The results of this study indicate significant changes in the intestinal flora with high altitude hypoxia, and establish a foundation for further research on the initiation and development of diseases and drug metabolism in high altitude hypoxia.
To investigate the influence factors and effects of metal or dissolving microneedles on the formation and healing of skin microchannels, the pencil-shaped or conical stainless steel microneedles with different lengths, tip to tip space and base area, and the pencil-shaped dissolving microneedles with different tip to tip space were used. The microneedles were applied to the skin of epilatory mice and rats, and the effects of various microneedle parameters, application parameters, and animals on the microchannels were explored by the transepidermal water loss (TEWL) and methylene blue staining. Visually observe the skin local irritation caused by the microneedles. The animal experiments were approved by the Animal Experiments Welfare and Ethical Committee of Zhejiang University of Technology. The application time of the microneedle should be maintained at 30 s or more. When the insertion forces were 2, 4, 8 N, and the TEWL initial values of the formed microchannels were 12.9, 33.0, 40.4 g·m-2·h-1, respectively. When the length of metal microneedle were 400, 600, 800 μm, and the TEWL initial values of the formed microchannels were 37.1, 40.4, 49.5 g·m-2·h-1, respectively. When the tip to tip space of metal microneedle were 400, 600, 800 μm, and the TEWL initial values of the formed microchannels were 33.2, 40.4, 55.8 g·m-2·h-1, respectively. When the base area of metal microneedle were 0.16, 0.35, 0.62 cm2, and the TEWL initial values of the formed microchannels were 35.1, 40.4, 67.1 g·m-2·h-1, respectively. The effects of conical and pencil-shaped microneedles are similar. When the tip to tip space of pencil shaped dissolving microneedle were 400, 600, 800 μm, and the TEWL initial values of the formed microchannels were 49.8, 60.5, 70.5 g·m-2·h-1, respectively. The TEWL baseline values of animal skins of different genders and series are different, but the tendency of microchannels formation and closure is similar. Visual inspection revealed that the slight erythema caused by the microneedles subsided within 24 h. Microneedles of different parameters have different effects on microchannels. The microchannels closed within 24 or 48 h, and the skin local irritation caused by microneedle was mild.
Protein-protein interactions (PPI) are involved in a variety of biological processes, including cell-to-cell interactions, metabolism and development control. The misregulation, post-translational modification and interference of PPI are related to a variety of human diseases, making the regulation of these interactions a very attractive field of drug discovery. In recent years, the interaction between MDM2 and p53 has become a research hotspot, which plays an important role in the treatment of tumors. But unfortunately there are no such inhibitors approved all over the world. In this view, recent advances of MDM2-p53 inhibitors were briefly described and its inhibitors with potential therapeutic activities in clinical studies were introduced.
To study the regulating effect of total phenolic acids from the stems and leaves of Salvia miltiorrhiza Bge. on the intestinal flora and short-chain fatty acids in spontaneous type 2 diabetic nephropathy mice, db/db mice were taken as the research object, and were treated with the total phenolic acid of Salvia miltiorrhiza Bge. Animal welfare and experimental procedures followed the regulations of the Animal Ethics Committee of Nanjing University of Chinese Medicine Drug Safety Evaluation Research Center. Fresh feces and cecal contents of mice were collected for analysis of intestinal flora composition and differential flora. Gas chromatography was used to detect short-chain fatty acids in fresh feces and cecal content. Then the correlation analysis of the two results was made. Compared with the normal group, the most significant decreased differential flora in the model group were g_Rikenellaceae_RC9_gut_group and g_Bacteroidales_S24-7_group, while the most significant increased were g_unclassified_f__Coriobacteriaceae and g_unclassified_p__Firmicutes. Compared with the blank group, the contents of isovaleric acid and valeric acid in fresh feces and the contents of 6 short-chain fatty acids in the cecal contents of the model group were significantly reduced (P < 0.01). After drug intervention, the intestinal flora disorder and the reduction of short-chain fatty acids were improved to varying degrees, and the effect of the total phenolic acids from the stems and leaves of Salvia miltiorrhiza Bge. was slightly better than that from the roots in regulating some flora and short-chain fatty acids. The results of correlation analysis showed that g_Rikenellaceae_RC9_gut_group was moderately positively correlated with acetic acid and isobutyric acid in the cecal contents (r > 0.4). It is suggested that the total phenolic acid from the stems and leaves of Salvia miltiorrhiza Bge. can improve the intestinal flora disorder of mice with type 2 diabetic nephropathy, and can regulate the content of short-chain fatty acids in the intestine via adjusting the content of some short-chain fatty acid-producing bacteria, thereby helping to restore normal.
Metabolomics based on liquid chromatography coupled with mass spectrometry (LC-MS) was used to study the initiation and development of diabetes in rats, and the ability of Ginkgo biloba extract (GBE) to ameliorate this pathology. Diabetes mellitus (DM) was induced by intra-peritoneal injection of streptozotocin. The rats were randomly divided into a normal control group treated with drug-free solution (NC), a normal control group treated with GBE (N-GBE), a DM group treated with drug-free solution (DM), and a DM group treated with GBE (D-GBE); rats were maintained on this protocol for 9 weeks. Rat plasma was collected from the sixth week to the ninth week and then analyzed with LC-MS. Animal experimentation was approved by the Committee on the Ethics of Animal Experiments of Xuzhou Medical University. Twelve plasma metabolites with continuous differentiation were monitored to indicate dysfunction of metabolic pathways including fatty acid metabolism, phospholipid metabolism, amino acid metabolism, tricarboxylic acid cycle activity, bile acid metabolism, and purine metabolism to confirm the occurrence and development of DM. Treatment with GBE partially reversed the changes seen in five metabolites in DM rats, indicating that GBE could prevent the occurrence and development of DM by acting on fatty acid metabolism, phospholipid metabolism, amino acid metabolism, and the tricarboxylic acid cycle.
Natural products are valuable resources for discovering new drugs. So far, screening bioactive compounds from organism extracts is still an important and challenging task. Traditional biometric guided method involves repeated fractionation steps and bioactivity tests, which are time-consuming, labor-consuming, and inefficient. Ligand fishing is a bioanalysis method for screening ligands from complex organism extracts based on intermolecular affinity interactions. It has the characteristics of strong specificity, high efficiency, and less requirement for sample pretreatment. In this review, we summarize the classification of ligand fishing strategy and its application in enzyme inhibitors screening. Finally, the development prospects of this technology are forecasted.