Er-Miao-Fang Extracts Inhibits Adipose Lipolysis and Reduces Hepatic Gluconeogenesis via Suppression of Inflammation

Bioinformatics study of the potential therapeutic effects of ginsenoside Rf in reversing nonalcoholic fatty liver disease

OBJECTIVE

Ginsenoside Rf, a tetracyclic triterpenoid only present in Panax ginseng, has been proven to relieve lipid metabolism and inflammatory reactions, which can be a potential treatment for nonalcoholic fatty liver disease (NAFLD). Therefore, this study aimed to reveal the underlying mechanisms of ginsenoside Rf in the treatment of early-stage NAFLD (NAFL) by using a bioinformatics method and biological experiments.

METHODS

Target genes associated with NAFL were screened from the Gene Expression Omnibus (GEO) database, a database repository of high-throughput gene expression data and hybridization arrays, chips, and microarrays. Subsequently, gene set enrichment analysis was performed by using Gene Ontology enrichment analysis tool. Then, the binding capacity between ginsenoside Rf and NAFL-related targets was evaluated by molecular docking. Finally, the FFA-induced HepG2 cell model treated with ginsenoside Rf was adopted to verify the effect of ginsenoside Rf and the related mechanisms.

RESULTS

There were 41 common differentially expressed genes in the GEO dataset. Gene Ontology and Reactome pathway enrichment analysis of the differentially expressed genes showed that many pathways could be related to the pathogenesis of NAFL, including those participating in the cytokine-mediated signaling pathway, G protein-coupled receptor signaling pathway, and response to lipopolysaccharide. Finally, the qRT-PCR analysis results indicated that ginsenoside Rf therapy could ameliorate the transcription of ANXA2, BAZ1A, DNMT3L and MMP9.

CONCLUSION

Our research discovered the relevant mechanisms and basic pharmacological effects of ginsenoside Rf in the treatment of NAFL. These results might facilitate the development of ginsenoside Rf as an alternative medication for NAFL.

Mangiferin protects against alcoholic liver injury via suppression of inflammation-induced adipose hyperlipolysis

Adipose dysfunction is closely associated with alcoholic liver disease. The impact of mangiferin on ethanol-induced liver injury and the probable underlying molecular mechanism has not been sufficiently addressed. In the present study, mice were subjected to a chronic plus a single binge ethanol feeding to induce liver injury. In addition, the differentiated adipocytes from primary mouse adipocytes were isolated and used for the mechanism studies. Our study demonstrated that mangiferin protects against ethanol induced adipose hyperlipolysis by restoring PDE3B stability, which is associated with activating the AMPK/TBK1 signaling and suppressing the noncanonical NF-κB activation, leading to the reduction of free fatty acid release and the amelioration of ethanol-induced liver injury. Our findings identify that mangiferin ameliorates alcoholic liver injury via suppression of inflammation-induced adipose hyperlipolysis, suggesting that mangiferin might be a potential effective agent for the management of alcoholic liver injury.

Herring Milt and Herring Milt Protein Hydrolysate Are Equally Effective in Improving Insulin Sensitivity and Pancreatic Beta-Cell Function in Diet-Induced Obese- and Insulin-Resistant Mice

Although genetic predisposition influences the onset and progression of insulin resistance and diabetes, dietary nutrients are critical. In general, protein is beneficial relative to carbohydrate and fat but dependent on protein source. Our recent study demonstrated that 70% replacement of dietary casein protein with the equivalent quantity of protein derived from herring milt protein hydrolysate (HMPH; herring milt with proteins being enzymatically hydrolyzed) significantly improved insulin resistance and glucose homeostasis in high-fat diet-induced obese mice. As production of protein hydrolysate increases the cost of the product, it is important to determine whether a simply dried and ground herring milt product possesses similar benefits. Therefore, the current study was conducted to investigate the effect of herring milt dry powder (HMDP) on glucose control and the associated metabolic phenotypes and further to compare its efficacy with HMPH. Male C57BL/6J mice on a high-fat diet for 7 weeks were randomized based on body weight and blood glucose into three groups. One group continued on the high-fat diet and was used as the insulin-resistant/diabetic control and the other two groups were given the high-fat diet modified to have 70% of casein protein being replaced with the same amount of protein from HMDP or HMPH. A group of mice on a low-fat diet all the time was used as the normal control. The results demonstrated that mice on the high-fat diet increased weight gain and showed higher blood concentrations of glucose, insulin, and leptin, as well as impaired glucose tolerance and pancreatic β-cell function relative to those on the normal control diet. In comparison with the high-fat diet, the replacement of 70% dietary casein protein with the same amount of HMDP or HMPH protein decreased weight gain and significantly improved the aforementioned biomarkers, insulin sensitivity or resistance, and β-cell function. The HMDP and HMPH showed similar effects on every parameter except blood lipids where HMDP decreased total cholesterol and non-HDL-cholesterol levels while the effect of HMPH was not significant. The results demonstrate that substituting 70% of dietary casein protein with the equivalent amount of HMDP or HMPH protein protects against obesity and diabetes, and HMDP is also beneficial to cholesterol homeostasis.

Herring Milt Protein Hydrolysate Improves Insulin Resistance in High-Fat-Diet-Induced Obese Male C57BL/6J Mice

Protein consumption influences glucose homeostasis, but the effect depends on the type and origin of proteins ingested. The present study was designed to determine the effect of herring milt protein hydrolysate (HPH) on insulin function and glucose metabolism in a mouse model of diet-induced obesity. Male C57BL/6J mice were pretreated with a low-fat diet or a high-fat diet for 6 weeks. Mice on the high-fat diet were divided into four groups where one group continued on the high-fat diet and the other three groups were fed a modified high-fat diet where 15%, 35%, and 70%, respectively, of casein was replaced with an equal percentage of protein derived from HPH. After 10 weeks, mice that continued on the high-fat diet showed significant increases in body weight, blood glucose, insulin, and leptin levels and exhibited impaired oral glucose tolerance, insulin resistance, and pancreatic β-cell dysfunction. Compared to mice fed the high-fat diet, the 70% replacement of dietary casein with HPH protein reduced body weight, semi-fasting blood glucose, fasting blood glucose, insulin, leptin, and cholesterol levels and improved glucose tolerance, homeostasis model assessment of insulin resistance (HOMA-IR), and homeostasis model assessment of β-cell function (HOMA-β) indices. The 35% replacement of dietary casein with HPH protein showed moderate effects, while the 15% replacement of dietary casein with HPH protein had no effects. This is the first study demonstrating that replacing dietary casein with the same amount of protein derived from HPH can prevent high-fat-diet-induced obesity and insulin resistance.

Expression and localization analyses of the cholinergic anti-inflammatory pathway and α7nAchR in different tissues of rats with rheumatoid arthritis

Rheumatoid arthritis (RA) is a complicated chronic multisystem autoimmune disease, wherein the inflammatory cascade leads to vasospasm and osteoclastogenesis, which ultimately results in bone and cartilage destruction. In this study, we investigated the expression and localization of the alpha-7 nicotinic receptor (α7nAchR) gene CHRNA7 in the heart, liver, spleen, lung, kidney, and joints of the collagen-induced arthritis (CIA) rat model. The CHRNA7 mRNA and protein expression levels in these tissues of rats from CIA and normal groups were analyzed via real-time quantitative polymerase chain reaction (RT-qPCR) and western blotting, respectively. The cellular localization of CHRNA7 protein was determined via immunohistochemistry (IHC) assays. CHRNA7 was expressed at varying levels in different tissues of rats from the groups, among which joints showed significantly higher CHRNA7 expression levels than other tissues (P < 0.05). CIA rats had significantly higher CHRNA7 expression levels in the spleen and joints than the control group rats (P < 0.05). Positive expression signals for CHRNA7 were detected in various tissues of CIA and control group rats, among which strong positive signals were detected in joint fibroblast-like synoviocytes (FLSs), endothelial cells, stromal cells, and macrophages. Our results further confirmed the involvement of the CAP in the onset and development of inflammatory responses in RA, suggesting that CHRNA7 may be a new therapeutic target for RA. This study is of great clinical and theoretical significance for understanding the differential expression of CHRNA7 in various tissues and cholinergic anti-inflammatory pathway (CAP)-targeted treatment of RA.