Punica granatum L.-derived omega-5 nanoemulsion improves hepatic steatosis in mice fed a high fat diet by increasing fatty acid utilization in hepatocytes.

Pomegranate seed oil (PSO) is mainly composed of punicic acid (PA), a polyunsaturated fatty acid also known as omega-5 (ω-5), a potent antioxidant associated with a variety of metabolic and cellular beneficial effects. However, the potential benefits of a nanoemulsified version of ω-5 (PSOn) have not been evaluated in a pathological liver condition. Here, we examined whether PSOn had beneficial effects on C57BL/6N mice fed a high-fat diet (HFD), specifically on hepatic steatosis. We observed that PSOn supplementation decreased body weight and body fat mass in control mice, whereas glucose intolerance, insulin resistance, energy expenditure, and hepatic steatosis were improved in both control mice and in mice fed a HFD. Interestingly, PSOn increased fatty acid oxidation in primary hepatocytes and antioxidant gene expression. Altogether, our data indicate that PSOn effectively reduces some of the HFD-derived metabolic syndrome indicators by means of an increase in fatty acid oxidation within hepatocytes.

Intestinal microbiota assessment in cirrhotic patients from a Mexican mestizo population. / Determinación de la microbiota intestinal en pacientes cirróticos de población mestizo-mexicana.

INTRODUCTION AND AIMS: The intestinal microbiota is significantly altered in cirrhotic patients, but the composition of the intestinal microbiota in Mexican patients with the pathology has not been reported. The present study is an attempt to determine the type of intestinal microbiota in healthy subjects and in patients of Mexican mestizo origin that present with cirrhosis of the liver. MATERIALS AND METHODS: Biochemical liver function parameters (ALT, AST, GGT, BIL-T, etc.) were determined in 23 cirrhotic patients and 21 control subjects. The intestinal microbiota was established through 16S ribosomal RNA gene sequencing. RESULTS: The cirrhotic patients had elevated levels of ALT, AST, GGT (105.2±77.7 vs. 20.99±8.5UI/L, 110±68.6 vs. 23.39±5.2, and 119.1±79.1 vs. 19.3±15.2UI/L, respectively), IL-6 (1.64±0.38pg/ml, P<.001), or TNFα (1.78±0.3, P<.05). The intestinal microbiota of the cirrhotic patients was less diverse, compared with that of the control subjects. At the level of the phylum, there was a significant increase in Proteobacteria and Bacteroidetes in the patients with cirrhosis, compared with the controls (6.2 vs. 4.9% and 44 vs. 46%, respectively, P<.01). In contrast, there was a decrease in Firmicutes, Actinobacteria, and Fusobacteria in the cirrhotic patients. There was an increase in the Campylobacter and Gemella families in the cirrhotic patients, whereas Streptococcus and Veillonella had a positive association with serum ALT or AST levels. CONCLUSIONS: To the best of our knowledge, the present study is the first to demonstrate the type of intestinal microbiota in Mexican patients with cirrhosis of the liver. The extension of the findings in a larger cohort of subjects and the metagenome analysis will enable the creation of data that can have relevant treatment implications for this group of patients in Mexico.

Dexamethasone represses cAMP rapid upregulation of TRH gene transcription: identification of a composite glucocorticoid response element and a cAMP response element in TRH promoter.

Hypothalamic proTRH mRNA levels are rapidly increased (at 1 h) in vivo by cold exposure or suckling, and in vitro by 8Br-cAMP or glucocorticoids. The aim of this work was to study whether these effects occurred at the transcriptional level. Hypothalamic cells transfected with rat TRH promoter (-776/+85) linked to the luciferase reporter showed increased transcription by protein kinase (PK) A and PKC activators, or by dexamethasone (dex), but co-incubation with dex and 8Br-cAMP decreased their stimulatory effect (as observed for proTRH mRNA levels). These effects were also observed in NIH-3T3-transfected cells supporting a characteristic of TRH promoter and not of hypothalamic cells. Transcriptional regulation by 8Br-cAMP was mimicked by noradrenaline which increased proTRH mRNA levels, but not in the presence of dex. PKA inhibition by H89 avoided 8Br-cAMP or noradrenaline stimulation. TRH promoter sequences, cAMP response element (CRE)-like (-101/-94 and -59/-52) and glucocorticoid response element (GRE) half-site (-210/-205), were analyzed by electrophoretic mobility shift assays with nuclear extracts from hypothalamic or neuroblastoma cultures. PKA stimulation increased binding to CRE (-101/-94) but not to CRE (-59/-52); dex or 12-O-tetradecanoylphorbol-13-acetate (TPA) increased binding to GRE, a composite site flanked by a perfect and an imperfect activator protein (AP-1) site in the complementary strand. Interference was observed in the binding of CRE or GRE with nuclear extracts from cells co-incubated for 3 h with 8Br-cAMP and dex; from cells incubated for 1 h, only the binding to GRE showed interference. Rapid cross-talk of glucocorticoids with PKA signaling pathways regulating TRH transcription constitutes another example of neuroendocrine integration.