Dan-gua Fang (丹瓜方) Improves Glycolipid Metabolic Disorders by Promoting Hepatic Adenosine 5'-monophosphate Activated Protein Kinase Expression in Diabetic Goto-kakizaki Rats

Objective：To investigate the effect of Dan-gua Fang（丹瓜方） on adenosine 5’-monophosphate（AMP） activated protein kinase（AMPK） α expression in liver and subsequent improvement of glucose and lipid metabolism.Methods：Forty 13-week-old diabetic Goto-Kakizaki（GK） rats were randomly divided into model,Dan-gua Fang,metformin and simvastatin groups（n=10 for each）,and fed high-fat diet ad libitum.Ten Wistar rats were used as normal group and fed normal diet.After 24 weeks,liver expression of AMPK α mRNA was assessed by real-time PCR.AMPK α and phospho-AMPK α protein expression in liver was evaluated by Western blot.Liver histomorphology was carried out after hematoxylin-eosin staining,and blood glucose（BG）,glycosylated hemoglobin A1c（HbA1c）,food intake and body weight recorded.Results：Similar AMPK α mRNA levels were found in the Dan-gua Fang group and normal group,slightly higher than the values obtained for the remaining groups（P〈0.05）.AMPK α protein expression in the Dan-gua Fang group animals was similar to other diabetic rats,whereas phospho-AMPK α（Thr-172） protein levels were markedly higher than in the metformin group and simvastatin group（P〈0.05）,respectively.However,phosphor-AMPKa/AMPK α ratios were similar in all groups.Dan-gua Fang reduced fasting blood glucose with similar strength to metformin,and was superior in reducing cholesterol,triglycerides,high-density lipoprotein cholesterol as well as improving low-density lipoprotein cholesterol in comparison with simvastatin and metformin.Dan-gua Fang decreases plasma alanine aminotransferase（ALT） significantly.Conclusion：Dan-gua Fang,while treating phlegm-stasis,could decrease BG and lipid in type 2 diabetic GK rats fed with high-fat diet,and effectively protect liver histomorphology and function.This may be partly explained by increased AMPK expression in liver.Therefore,Dan-gua Fang might be an ideal drug for comprehensive Intervention for glucose and lipid metabolism disorders in type 2 diabetes mellitus.

Diabetes,insulin and cancer risk

There is a consensus that both type 1 and type 2 diabetes are associated with a spectrum of cancers but the underlying mechanisms are largely unknown.On the other hand,there are ongoing debates about the risk association of insulin use with cancer.We have briefly reviewed recent related research on exploration of risk factors for cancer and pharmacoepidemiological investigations into drug use in diabetes on the risk of cancer,as well as the current understanding of metabolic pathways implicated in intermediary metabolism and cellular growth.Based on the novel findings from the Hong Kong Diabetes Registry and consistent experimental evidence,we argue that use of insulin to control hyperglycemia is unlikely to contribute to increased cancer risk and that dysregulations in the AMPactivated protein kinase pathway due to reduced insulin action and insulin resistance,the insulin-like growth factor-1(IGF-1)-cholesterol synthesis pathway and renin-angiotensin system,presumably due to reduced insulin secretion and hyperglycemia,may play causal roles in the increased risk of cancer in diabetes.Further exploration into the possible causal relationships between abnormalities of these pathways and the risk of cancer in diabetes is warranted.

Investigation and experimental validation of curcumin-related mechanisms against hepatocellular carcinoma based on network pharmacology

Objective:To determine the potential molecular mechanisms underlying the therapeutic effect of curcumin on hepatocellular carcinoma(HCC)by network pharmacology and experimental in vitro validation.Methods:The predictive targets of curcumin or HCC were collected from several databases.the identified overlapping targets were crossed with Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analyses using the Database for Annotation,Visualization,and Integrated Discovery(DAVID)platform.Two of the candidate pathways were selected to conduct an experimental verification.The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide tetrazolium(MTT)assay was used to determine the effect of curcumin on the viability of Hep G2 and LO2 cells.The apoptosis and autophagy of Hep G2 cells were respectively detected by flow cytometry and transmission electron microscopy.Besides,western blot and real-time polymerase chain reaction(PCR)were employed to verify the p53 apoptotic pathway and adenosine 5’-monophosphate(AMP)-activated protein kinase(AMPK)autophagy pathway.Hep G2 cells were pretreated with pifithrin-α(PFT-α)and GSK690693 for further investigation.Results:The 167 pathways analyzed by KEGG included apoptosis,autophagy,p53,and AMPK pathways.The GO enrichment analysis demonstrated that curcumin was involved in cellular response to drug,regulation of apoptotic pathway,and so on.The in vitro experiments also confirmed that curcumin can inhibit the growth of Hep G2 cells by promoting the apoptosis of p53 pathway and autophagy through the AMPK pathway.Furthermore,the protein and messenger RNA(m RNA)of the two pathways were downregulated in the inhibitor-pretreated group compared with the experimental group.The damage-regulated autophagy modulator(DRAM)in the PFT-α-pretreated group was downregulated,and p62 in the GSK690693-pretreated group was upregulated.Conclusions:Curcumin can treat HCC through the p53 apoptotic pathway and the AMPK/Unc-51-like kinase 1(ULK1)autophagy pathway,in which the mutual transformation of autophagy and apoptosis may occur through DRAM and p62.