Modulation of hippocampal TLR4/BDNF signal pathway using probiotics is a step closer towards treating cognitive impairment in NASH model.

BACKGROUND AND AIM: Disturbance of gut microbiota plays a role in induction and progression of non alcoholic steatohepatitis (NASH) and the associated cognitive dysfunction. We supposed that high fat diet (HFD)-induced dysbiosis may lead to NASH/cognitive impairment co-morbidities through hippocampal TLR4/BDNF signaling pathway and the regaining of microbiota balance through probiotics could provide a therapeutic option. METHODOLOGY: Four groups of male Wister rats were used; Naïve, Lactobacillus Plantarum EMCC-1039 (LP EMCC-1039), NASH and NASH+ LP EMCC-1039 groups. After induction of NASH with high fat diet (HFD), LP EMCC-1039 was given daily by oral gavage in the last two weeks of experiment to the treated group. Body weight percentage (BW%) changes, Lee index (LI), liver function tests, expression of BDNF, TLR4 with RT-PCR and quantification of BDNF, TLR4 by ELISA were measured . Histological studies and assessment of cognitive function were also performed. RESULTS: NASH group showed an increase in BW% and LI . It was associated with cognitive deficits, an increase in hepatic, hippocampal TLR4 expression and decline in BDNF expression and protein, all p values were <0.05. Histological examination revealed significant decrease in number of viable cells and shrinking of pyramidal cells in hippocampus (p<0.05). Treatment with LP EMCC-1039 improved all these pathological changes significantly (p<0.05) with negative correlation between NAFLD activity score (NAS) and cognitive measurements. Additionally, hepatic and hippocampal TLR4 expression were decreased and BDNF expression and quantity were increased. CONCLUSIONS: Dysbiosis-induced NASH was associated with cognitive impairment and a probiotic (LP EMCC-1039) supplementation has beneficial effect through modulation of TLR4/BDNF signaling pathway.

Involvement of TLR4/ CXCL9/ PREX-2 pathway in the development of hepatocellular carcinoma (HCC) and the promising role of early administration of lactobacillus plantarum in Wistar rats.

BACKGROUND AND AIM: Improvement of gut microbiota may help in preventing the progression of cirrhosis. We supposed that Lactobacillus Plantarum (L. Plantarum) protects the cirrhotic liver through suppression of TLR4/ CXCL9/ PREX-2. METHODOLOGY: Rats were divided into two groups. Group I, lasts for six weeks and Group II lasts for 12 weeks. Each group was subdivided into: naïve, Lactobacillus Plantarum (L. Plantarum), thioacetamide (TAA) and TAA + L. Plantarum. Liver function tests, α fetoprotein (AFP) levels, CXCL9, PREX-2 and TLR4 expression were assessed. Histological studies were performed. RESULTS: TAA induced significant deterioration in liver functions and increased AFP. There was periportal cirrhosis, vacuolated hepatocytes, decrease hepatocyte parrafin-1 (hep par-1) expression, increase proliferating cell nuclear antigen (PCNA) positive nuclei and cytokeratin AE1/AE3. The PCR results showed significant increase in TLR4, CXCL9 and PREX-2 expression. Early administration of L. Plantarum significantly decreased the expression of TLR4, CXCL9 and PREX-2 together with improvement in liver function and prevented the pathological changes. CONCLUSIONS: The cirrhotic complications induced by TAA are through activation of TLR4/ CXCL9/ PREX-2 pathway and could be prevented by the early administration of L. Plantarum.

Insights into hepatic and renal FXR/DDAH-1/eNOS pathway and its role in the potential benefit of rosuvastatin and silymarin in hepatic nephropathy.

OBJECTIVES: The repression of renal Farnesoid X Receptor (FXR) had been shown to result from lack of bile acid production from cirrhotic liver. We hypothesized that silymarin and rosuvastatin (Rvs) could have a hepatorenal therapeutic effects in hepatic nephropathy through induction of FXR. METHODS: Forty two male Wistar rats were used; naïve (n = 12); six of them were sacrificed after 4 weeks and six continued till the end of the experiment. Thirty rats were treated as follows: Rvs, silymarin, thioacetamide (TAA), TAA + Rvs and TAA + silymarin. Liver and kidney function tests as well as the renal and hepatic expression of transforming growth factor ß1 (TGFß1), FXR, dimethylarginine dimethylaminohydrolase-1 (DDAH-1) and eNOS were performed. Histological and immuno-histochemical studies of liver and kidney were also done. RESULTS: TAA-inducted liver cirrhosis was associated with significant deterioration of liver and renal functions together with increasing expression of hepatic and renal TGFß1 and decreasing expression of hepatic and renal FXR, DDAH-1 and eNOS. Giving silymarin or Rvs induced hepatic and renal improvement which was evidenced biochemically and histologically. Significant positive correlation was detected between all the investigated biomarkers except for the correlation between FXR and TGFß1 which was negative. CONCLUSIONS: In conclusion, liver cirrhosis is associated with deterioration of renal functions. Silymarin and Rvs have a potential hepatorenal therapeutic benefit through simultaneous enhancement of FXR/DDAH-1/eNOS pathway in both organs.

Potential involvement of JNK1 repression in the hepatic effect of sitagliptin and metformin in rats subjected to high fat diet and chronic mild distress.

BACKGROUND: Depression and non-alcoholic steatohepatitis (NASH) are highly co-morbid, and hepatic JNK pathway may be involved in their relation. AIM: To evaluate the impact of depression on NASH through the involvement of JNK1 and to assess the effect of sitagliptin and metformin on hepatic JNK1 expression in both NASH and NASH associated with depression. METHODS: Eight groups of male Wistar rats were used: naïve rats, non-stressed NASH, non-stressed NASH sitagliptin treated, non-stressed NASH metformin treated, stressed, stressed NASH untreated, stressed NASH sitagliptin treated and stressed NASH metformin treated. Behavioral, biochemical, molecular and histopathological studies were performed. RESULTS: Non-stressed NASH group showed depressive like symptoms, disturbed glucose homeostasis, impairment of liver functions, decrease adiponectin and increase malondialdehyde, which were aggreviated by stress. Sitagliptin produced significant improvement compared to metformin regarding biochemical and histopathological parameters. Furthermore, sitagliptin significantly decreased expression of hepatic JNK1 in both stressed and non-stressed rats. All these changes were accompanied by significant improvement of behavioral changes. CONCLUSIONS: The link between NASH and depression raised the role of JNK activation through increase expression of JNK1. Since sitagliptin was associated with preferable effects than metformin, therefore, it is potentially preferred in the management of either NASH or NASH associated with depression.