Probiotic Lactobacillus gasseri SBT2055 improves glucose tolerance and reduces body weight gain in rats by stimulating energy expenditure.

Probiotic Lactobacillus gasseri SBT2055 (LG2055) reduces postprandial TAG absorption and exerts anti-obesity effects in rats and humans; however, the underlying mechanisms are not fully understood. In the present study, we addressed the mechanistic insights of the anti-obesity activity of LG2055 by feeding Sprague-Dawley rats diets containing skimmed milk fermented or not by LG2055 for 4 weeks and by analysing energy expenditure, glucose tolerance, the levels of SCFA in the caecum and serum inflammatory markers. Rats fed the LG2055-containing diet demonstrated significantly higher carbohydrate oxidation in the dark cycle (active phase for rats) compared with the control group, which resulted in a significant increase in energy expenditure. LG2055 significantly reduced cumulative blood glucose levels (AUC) compared with the control diet after 3 weeks and increased the molar ratio of butyrate:total SCFA in the caecum after 4 weeks. Furthermore, the LG2055-supplemented diet significantly reduced the levels of serum amyloid P component - an indicator of the inflammatory process. In conclusion, our results demonstrate that, in addition to the inhibition of dietary TAG absorption reported previously, the intake of probiotic LG2055 enhanced energy expenditure via carbohydrate oxidation, improved glucose tolerance and attenuated inflammation, suggesting multiple additive and/or synergistic actions underlying the anti-obesity effects exerted by LG2055.

Effect of dietary resveratrol on the metabolic profile of nutrients in obese OLETF rats.

BACKGROUND: Resveratrol (trans-3,4',5-trihydroxystilbene) is a naturally occurring phytoalexin produced by plants in response to various stresses. Several studies have shown that resveratrol is present in significant amounts in a variety of human diets, including wines, grapes, berries, and peanuts, and it possesses several beneficial health properties, such as atheroprotective, anti-obesity, anti-cancer, anti-inflammatory and antioxidant activities. In this study, we evaluated the effect of resveratrol on the pathogenesis of obesity and the metabolic profile of nutrients in non-high fat-fed obese OLETF rats. RESULTS: Although lipid parameters in the serum and liver were not changed, the accumulation of abdominal white adipose tissues was markedly prevented in resveratrol diet-fed OLETF rats after 4 weeks of feeding. The results of the respiratory gas analysis indicated that dietary resveratrol induced the partial enhancement of fat metabolism and sparing actions for carbohydrate and protein at 1 week and 3 weeks of feeding in OLETF rats. Additionally, the adipose mRNA level of carnitine palmitoyltransferase in the resveratrol diet-fed OLETF rats was higher than the control rats after 4 weeks of feeding. CONCLUSION: Our study demonstrated that dietary resveratrol can prevent obesity through a change in the metabolic profile of nutrients in obese OLETF rats.

Polyphenolic extract of lotus root (edible rhizome of Nelumbo nucifera) alleviates hepatic steatosis in obese diabetic db/db mice.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is emerging as the most common liver disease of industrialized countries. Thus, discovering food components that can ameliorate NAFLD is of interest. Lotus root, the edible rhizome of Nelumbo nucifera, contains high levels of polyphenolic compounds, and several health-promoting properties of lotus root have been reported. In this study, we tested whether feeding a polyphenolic extract of lotus root to db/db mice protects them from hepatic steatosis. RESULTS: After 3 weeks of feeding, the hepatomegaly and hepatic triglyceride accumulation were markedly alleviated in the lotus polyphenol-diet-fed db/db mice relative to the control mice. Although the lipolytic enzyme activity was not changed, the activities of lipogenic enzymes, such as fatty acid synthase and malic enzyme, were significantly lower in the lotus polyphenol diet-fed db/db mice. Additionally, the ESI-IT/MS and MALDI-TOF MS spectra revealed the presence of B-type proanthocyanidin polymers with polymerization degree up to 9 in the polyphenolic lotus root extract. CONCLUSION: We speculate that the condensed tannins contained in lotus root can alleviate hepatic steatosis by suppressing the lipogenic enzyme activity in the livers of db/db mice.

Pterostilbene, a dimethylated analog of resveratrol, promotes energy metabolism in obese rats.

Pterostilbene (trans-3,5-dimethoxy-4-hydroxystilbene) is a dimethylated analog of resveratrol and has been reported to exert various pharmacological effects. In this study, we evaluated the effect of pterostilbene on the pathogenesis of obesity and energy metabolism in obese rats. Pterostilbene significantly activates silent mating type information regulation 2 homolog-1 and peroxisome proliferator-activated receptor-alpha in vitro. At 4 weeks a 0.5% pterostilbene diet markedly suppressed the abdominal white adipose tissue (WAT) accumulation in obese rats. The oxygen consumption and energy expenditure were significantly higher in the pterostilbene group, and pterostilbene increased the fat metabolism rather than the carbohydrate metabolism in obese rats. The mRNA level of uncoupling protein, a thermogenic regulator, was increased and the mRNA levels of fatty acid synthase and leptin, which are involved in lipogenesis and fat storage, were markedly decreased in WAT after the pterostilbene feeding. These results suggest that pterostilbene prevents WAT accumulation through the enhancement of energy metabolism and partly the suppression of lipogenesis in obese OLETF rats.

Soy Protein Isolate Suppresses Lipodystrophy-induced Hepatic Lipid Accumulation in Model Mice.

Lipodystrophies are acquired and genetic disorders characterized by the complete or partial absence of body fat with a line of metabolic disorders, including hepatic steatosis. Because soy protein isolate (SPI) has been reported to reduce cholesterol and triglyceride levels in animals and humans, we explored the effect of SPI on the pathophysiology of hepatic lipid accumutaion in a diet-induced lipodystrophy model mice. Four weeks of the lipodystrophy model diet induced hepatic lipid accumulation concomitant with marked deficiencies of adipose tissue and serum adipocytokines in mice. However, supplementing the lipodystrophy model diet with SPI could alleviate the hepatic lipid acculation without affecting the lipoatrophic effect of the diet. Enhanced lipogenesis is the principal mechanism of hepatic steatosis in this model, but SPI supplementation significantly attenuated the increase in enzyme activity and/or mRNA expression. Additionally, SPI supplementation upregulated the hepatic mRNA expression of an enzyme involved in cholesterol catabolism. In conclusion, our results indicate the possibility of dietary SPI to attenuate lipodystorophy-induced hepatic steatosis through the direct reduction of hepatic lipogenesis without affecting adipocytokine production.

Gastritis associated with Epstein-Barr virus infection.

Infectious mononucleosis is a self-limiting clinical syndrome caused by primary Epstein-Barr virus (EBV) infection. EBV-associated gastritis, however, has rarely been documented. We report a case of a 17-year-old woman who presented with fever, sore throat, and epigastric pain. Upper endoscopy revealed diffuse granular mucosae and elevated lesions in the stomach. Histologically, the biopsied mucosa was infiltrated by numerous atypical lymphocytes. From clinical, histopathologic, immunohistochemical, and in situ hybridization analyses, we diagnosed EBV-associated gastritis. Her symptoms spontaneously resolved, and follow-up endoscopy revealed improvement and no atypical lymphocytes. To prevent misdiagnosis and unnecessary treatment, the possibility of EBV-associated gastritis should be considered.