The traditional Chinese formulae Ling-gui-zhu-gan decoction alleviated non-alcoholic fatty liver disease via inhibiting PPP1R3C mediated molecules

BACKGROUND

Ling-gui-zhu-gan decoction (LGZG), a classic traditional Chinese medicine formula, has been confirmed to be effective in improving steatosis in non-alcoholic fatty liver disease (NAFLD). However, the mechanism under the efficacy remains unclear. Hence, this study was designed to investigate the mechanisms of LGZG on alleviating steatosis.

METHODS

Twenty four rats were randomly divided into three groups: normal group, NAFLD group, fed with high fat diet (HFD) and LGZG group (fed with HFD and supplemented with LGZG). After 4 weeks intervention, blood and liver were collected. Liver steatosis was detected by Oil Red O staining, and blood lipids were biochemically determined. Whole genome genes were detected by RNA-Seq and the significant different genes were verified by RT-qPCR. The protein expression of Protein phosphatase 1 regulatory subunit 3C (PPP1R3C) and key molecules of glycogen and lipid metabolism were measured by western blot. Chromophore substrate methods measured glycogen phosphorylase (GPa) activity and glycogen content.

RESULTS

HFD can markedly induce hepatic steatosis and promote liver triglyceride (TG) and serum cholesterol (CHOL) contents, while liver TG and serum CHOL were both markedly decreased by LGZG treatment for 4 weeks. By RNA sequencing, we found that NAFLD rats showed significantly increase of PPP1R3C expression and LGZG reduced its expression. RT-qPCR and Western blot both verified the alteration of PPP1R3C upon LGZG intervention. LGZG also promoted the activity of glycogen phosphorylase liver type (PYGL) and inhibited the activity of glycogen synthase (GS) in NAFLD rats, resulting in glycogenolysis increase and glycogen synthesis decrease in the liver. By detecting glycogen content, we also found that LGZG reduced hepatic glycogen in NAFLD rats. In addition, we analyzed the key molecules in hepatic de novo lipogenesis and cholesterol synthesis, and indicated that LGZG markedly inhibited the activity of acetyl-CoA carboxylase (ACC), sterol receptor element-binding protein-1c (SREBP-1c) and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), resulting in lipid synthesis decrease in the liver.

CONCLUSION

Our data highlighted the role of PPP1R3C targeting pathways, and found that hepatic glycogen metabolism might be the potential target of LGZG in preventing NAFLD.

Ling-gui-zhu-gan decoction alleviates hepatic steatosis through SOCS2 modification by N6-methyladenosine

BACKGROUND

The ling-gui-zhu-gan (LGZG) decoction is a classic formula in traditional chinese medicine (TCM) and is widely used in clinical settings. Recently, the LGZG decoction was demonstrated to have an effect in alleviating hepatic steatosis induced by a high-fat diet (HFD). However, the mechanisms underlying this therapeutic effect remain unclear. The present study was designed to evaluate the effect and explore possible mechanisms of action of the LGZG decoction in nonalcoholic fatty liver disease (NAFLD).

METHODS

Liver tissue and blood samples were harvested. Liver steatosis, triglyceride (TG), liver total cholesterol (TC), liver low-density lipoprotein (LDL), serum almandine aminotransferase (ALT), aspartate aminotransferase (AST), and free fatty acid (FFA) were assayed. N6-methyladenosine (m6A) levels were estimated using an m6A RNA methylation quantification kit and immunohistochemistry. The m6A methylome was detected through methylated RNA immunoprecipitation sequencing (MeRIP-seq), followed by data analysis. The expression levels of differentially methylated genes (DMGs) were determined using real-time polymerase chain reaction and western blotting.

RESULTS

The LGZG decoction significantly alleviated hepatic steatosis and reduced m6A levels. MeRIP-seq revealed the coding sequence (CDS) domain to be the most critical modification site for m6A methylation, and the molecular functions of DMGs predominantly included insulin-like growth factor receptor binding and fatty acid metabolism and degradation. Further, LGZG treatment could reduce the m6A methylation levels of suppressor of cytokine signaling 2 (SOCS2), along with the expression of SOCS2 at mRNA and protein levels.

CONCLUSIONS

The LGZG decoction is an effective formula for treating NAFLD, and the possible mechanisms underlying its action could be related to N6-methyladenosine modification-medicated SOCS2.

Gan-Jiang-Ling-Zhu decoction alleviates hepatic steatosis in rats by the miR-138-5p/CPT1B axis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a commonly-encountered chronic liver disease which lacks verified pharmacological interventions. Gan-Jiang-Ling-Zhu decoction (GJLZ) is a classic formula utilized in clinical practice. In this study, we aimed to evaluate the therapeutic effect of GJLZ in NAFLD and explore the possible underlying mechanisms.

METHODS

Twenty-four rats were randomly divided into three groups: normal group, fed with chow diet for 8 weeks; model group, fed with high fat diet for 8 weeks; and GJLZ group, initially fed HFD for 4 weeks, and then administered the GJLZ decoction for 4 weeks by oral gavage while continuously feeding HFD. Rats were sacrificed after the intervention, and liver tissues and blood samples were harvested. Liver steatosis was detected by HE and Oil Red O staining. Body weight and liver index were analyzed. Liver triglyceride (TG), total cholesterol (TC), and low-density lipoprotein (LDL), serum almandine aminotransferase (ALT), aspartate aminotransferase (AST), and nonesterified fatty acid (NEFA) were assayed using commercial kits. Differentially expressed genes were identified by RNA-sequencing and verified using real-time PCR (RT-PCR) and western blotting. Whole miRNAs were detected by RNA-sequence analysis, and mRNA-targeted miRNAs were verified by RT-PCR. The miRNA-mRNA regulation pattern was confirmed using the dual-luciferase reporter assay.

RESULTS

Treatment with GJLZ significantly improved hepatic steatosis and inflammation, reduced liver index and liver TG content, and also significantly reduced serum ALT and AST levels. Based on the results of RNA-sequence analysis, five differentially expressed genes (DEGs) in the peroxisome proliferator-activated receptor (PPAR) signaling pathway were recognized. RT-PCR confirmed that carnitine palmitoyltransferase 1b (CPT1B) expression was significantly regulated by GJLZ treatment. GJLZ decoction intervention also increased significantly hydroxyacyl-CoA dehydrogenase trifunctional multienzyme complex subunit alpha (HADHA) expression. Next, miRNA profiling and screening were performed based on CPT1B alteration. Rno-miR-138-5p likely responded to GJLZ intervention, and rno-miR-138-5p inhibitor increased CPT1B expression while rno-miR-138-5p mimic reduced CPT1B expression. When CPT1B mutated, miR-138-5p mimic and inhibitor could not regulate the luciferase activity of CPT1B.

CONCLUSIONS

GJLZ is an effective formula for NAFLD management, and its possible mechanism of action involves the regulation of CPT1B expression via rno-miR-138-5p.

Bavachalcone-induced manganese superoxide dismutase expression through the AMP-activated protein kinase pathway in human endothelial cells

Mitochondrial oxidative stress has been suggested as a major etiological factor in cardiovascular diseases. Manganese superoxide dismutase (MnSOD) is an essential antioxidant mitochondrial enzyme. Although polyphenols can induce MnSOD expression, their mechanism of action remains unclear. We examined the effect of bavachalcone, a bioactive compound isolated from Psoralea corylifolia, on MnSOD protein expression and explored whether this effect is mediated through the AMP-activated protein kinase (AMPK) signaling pathway. Our data showed that bavachalcone enhanced the luciferase activity of the MnSOD promoter and increased MnSOD mRNA and protein expressions. Moreover, bavachalcone suppressed the mitochondrial superoxide production in endothelial cells. Conversely, bavachalcone stimulated liver kinase B1 and AMPKα phosphorylation. mRNA interference by using short hairpin RNA (shRNA) of AMPK inhibited bavachalcone-induced MnSOD expression. A-769662, an AMPK activator, also stimulated AMPK activity and increased MnSOD expression. Furthermore, AMPK knockdown by shRNA-AMPK reversed the inhibitory effects of bavachalcone on mitochondrial superoxide production in endothelial cells. These findings indicate that bavachalcone can protect the endothelial function by increasing AMPK activity and MnSOD expression and reducing mitochondrial oxidative stress. .

Bavachalcone Enhances RORα Expression, Controls Bmal1 Circadian Transcription, and Depresses Cellular Senescence in Human Endothelial Cells

The circadian clock regulates many aspects of (patho)physiology in the central nervous system and in the peripheral tissues. RAR-related orphan receptor α (RORα), an orphan nuclear receptor, is involved in circadian rhythm regulation, including regulation of cardiovascular function. Bavachalcone, a prenylchalcone, is a major bioactive chalcone isolated from Psoralea corylifolia. This natural ingredient activated RORα1 luciferase reporter activity on drug screening. In addition, bavachalcone induced RORα1 expression in mRNA and protein levels in a dose-dependent manner and enhanced the circadian amplitude of Bmal1 mRNA expression after serum shock. Moreover, bavachalcone suppressed senescence in human endothelial cells and mRNA expression of p16(ink4a) (a marker of replicative senescence) and IL-1α (a proinflammatory cytokine of the senescence-associated secretory phenotype). These inhibitory effects were partially reversed by the RORα inhibitor VPR-66. Our results demonstrate that bavachalcone, as a natural medicine ingredient, has a pharmacological function in regulating RORα1.