ETHNOPHARMACOLOGICAL RELEVANCE: The fruits of Terminalia bellerica Roxb. (Combretaceae) and T. chebula Retz. (Combretaceae) are important components of triphala, a popular Ayurvedic formulation, for treating diabetes in Indian traditional medicine. AIM OF THE STUDY: The aim of this study was to evaluate the effects of the constituents of T. bellerica and T. chebula fruit extracts on PPAR? and PPAR? signaling/expression, cellular glucose uptake and adipogenesis. MATERIALS AND METHODS: PPAR? and PPAR?
Medicinal plants are a rich source of ligands for nuclear receptors. The present study was aimed to screen a collection of plant extracts for PPAR?/?-activating properties and identify the active extract that can stimulate cellular glucose uptake without enhancing the adipogenesis. A reporter gene assay was performed to screen ethanolic extracts of 263 plant species, belonging to 94 families, for activation of PPAR? and PPAR?. Eight extracts showed activation of PPAR?, while 22 extracts showed activation of PPAR?.
The thiazolidinedione (TZDs) class of drugs are very effective for the treatment of type 2 diabetes mellitus (T2DM). But due to the adverse effects of synthetic TZDs, their use is strictly regulated. The therapeutic actions of TZDs are mediated via modulation of peroxisome proliferator-activated receptor gamma (PPAR?). Naturally occurring PPAR? modulators are more desirable as they lack the serious adverse effects caused by TZDs. This has prompted the exploitation of medicinal plants used in traditional medicine, for their potential PPAR? activity.
Calorie restriction extends lifespan in organisms ranging from yeast to mammals. In yeast, the SIR2 gene mediates the life-extending effects of calorie restriction. Here we show that the mammalian SIR2 orthologue, Sirt1 (sirtuin 1), activates a critical component of calorie restriction in mammals; that is, fat mobilization in white adipocytes. Upon food withdrawal Sirt1 protein binds to and represses genes controlled by the fat regulator PPAR-gamma (peroxisome proliferator-activated receptor-gamma), including genes mediating fat storage.
Calorie restriction extends lifespan in organisms ranging from yeast to mammals. In yeast, the SIR2 gene mediates the life-extending effects of calorie restriction. Here we show that the mammalian SIR2 orthologue, Sirt1 (sirtuin 1), activates a critical component of calorie restriction in mammals; that is, fat mobilization in white adipocytes. Upon food withdrawal Sirt1 protein binds to and represses genes controlled by the fat regulator PPAR-gamma (peroxisome proliferator-activated receptor-gamma), including genes mediating fat storage.
BACKGROUND: In a variety of organisms, including mammals, caloric restriction improves metabolic status and lowers the incidence of chronic-degenerative diseases, ultimately leading to increased lifespan. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that knockout mice for Eps8, a regulator of actin dynamics, display reduced body weight, partial resistance to age- or diet-induced obesity, and overall improved metabolic status. Alteration in the liver gene expression profile, in behavior and metabolism point to a calorie restriction-like phenotype in Eps8 knockout mice.
In Ayurvedic medicine, Salacia reticulata is known to be useful against various metabolic diseases, including diabetes and obesity. In this study, we attempted to clarify the antiobesity mechanism and the safety of S. reticulata in vivo and in vitro. We gave ordinary MF feed, alone or mixed with S. reticulata (0.3 or 1.0%), to Tsumura Suzuki obesity diabetes (TSOD) mice (spontaneous obese type II diabetes model mice) and Tsumura Suzuki non-obese (TSNO) mice (the corresponding reference animals), ad libitum for 2 months.
ETHOPARMACOLOGICAL RELEVANCE: Salacia reticulata, a herbal medicine which has been used for the treatment of early diabetes in Ayurvedic medicine, is reported to have an anti-obesity effect and to be useful in the treatment of diabetes mellitus, insulin resistance and other metabolic diseases. AIM OF THE STUDY: The present study was performed to elucidate the mechanism of action of Salacia reticulata with special attention to the adipocytes as the tissue primarily involved in the pathology of metabolic diseases.
ETHNOPHARMACOLOGICAL RELEVANCE: The fruits of Terminalia bellerica Roxb. (Combretaceae) and T. chebula Retz. (Combretaceae) are important components of triphala, a popular Ayurvedic formulation, for treating diabetes in Indian traditional medicine. AIM OF THE STUDY: The aim of this study was to evaluate the effects of the constituents of T. bellerica and T. chebula fruit extracts on PPARα and PPARγ signaling/expression, cellular glucose uptake and adipogenesis.
Muscle and fat cells develop insulin resistance when cultured under hyperinsulinemic conditions for sustained periods. Recent data indicate that early insulin signaling defects do not fully account for the loss of insulin action. Given that cortical filamentous actin (F-actin) represents an essential aspect of insulin regulated glucose transport, we tested to see whether cortical F-actin structure was compromised during chronic insulin treatment.
