Vanillin induces adipocyte differentiation in 3T3-L1 cells by activating extracellular signal regulated kinase 42/44

High expression of an unknown long noncoding RNA RP11-290L1.3 from GDM macrosomia and its effect on preadipocyte differentiation

AIMS

Gestational diabetes mellitus (GDM)-induced macrosomia is predominantly characterized by fat accumulation, which is closely related to adipocyte differentiation. An unknown long noncoding RNA RP11-290L1.3, referred to as RP11, was identified to be dramatically upregulated in the umbilical cord blood of women with GDM-induced macrosomia in our previous study. We conducted this study to identify the function of RP11 in GDM-induced macrosomia.

METHODS

The effects of RP11 gain- and loss-of-function on HPA-v (human preadipocytes-visceral) adipogenesis were determined with lentivirus mediated cell transduction. The mRNA and protein expression levels of adipogenesis makers were evaluated by qPCR/Western blot. Then, we performed the microarray and pathway analysis to explore the possible mechanisms by which RP11 regulates adipogenesis.

RESULTS

Overexpression of RP11 significantly enhanced adipocyte differentiation and increased the mRNA and protein expression levels of adipogenesis makers, such as PPARγ, SREBP1c, and FASN by qPCR/Western blot. Knockdown of RP11 showed opposite effects. Microarray and pathway analysis showed, after RP11 knockdown, 1612 genes were upregulated, and 583 genes were down-regulated which were found to be mainly involved in metabolic pathways, insulin signaling pathway and MAPK signaling pathway.

CONCLUSION

In conclusion, the unknown lncRNA RP11 serves as a positive factor on preadipocyte differentiation which could shed light on fetal fat accumulation in GDM.

Ayurvedic anti-diabetic formulation Lodhrasavam inhibits alpha-amylase, alpha-glucosidase and suppresses adipogenic activity in vitro

BACKGROUND

The patho-physiological cross-talk between diabetes and obesity is well established. However, the choices of drugs suitable for combined treatment of diabetes and obesity are limited. Integration of complementary and alternative medicines (CAMs), like Ayurveda, with modern medicine would be a promising strategy to fill this gap. The diagnostic principles of Ayurveda define obesity as one of the predisposing factors of Madhumeha (correlated as diabetes) and recommends specific formulations for managing obese-diabetes. Lodhrasavam is one such poly-herbal formulation prescribed for obese-diabetic patients.

OBJECTIVES

The present study is an attempt to demonstrate the possible modes of action of Lodhrasavam, built on the hypothesis that the formulation can exert both anti-diabetic and anti-obesity actions.

MATERIALS AND METHODS

Lodhrasavam, following simulated gastro-intestinal digestion, was monitored for inhibition of α-amylase, α-glucosidase (key digestive enzyme targets of anti-diabetic drugs) and adipogenesis using standard in vitro model systems.

RESULTS

Lodhrasavam digest inhibited α-amylase (90%) and α-glucosidase (78%) activity as well as reduced the differentiation of 3T3-L1 fibroblasts to adipocytes. Upon fractionation, the enzyme inhibitory activity and anti-adipogenic activity of the digest were found distributed in different solvent fractions. This partly indicates a potential pharmacological networking of chemically and functionally diverse bioactive molecules in Lodhrasavam.

CONCLUSION

The study provides a possible mode of action and an experimental support for the Ayurvedic use of Lodhrasavam for managing obese-diabetes. Generating scientific evidences and understanding the modes of action, in contemporary scientific language, would essentially help in expanding global acceptance of potentials of CAMs in the management of life style disorders.

Characterization of Secondary Metabolites from Purple Ipomoea batatas Leaves and Their Effects on Glucose Uptake

Ipomoea batatas has long been used in folk medicine for the treatment of hyperglycemia or as a food additive for the prevention of type 2 diabetes. However, neither the plant extract nor its active components have been evaluated systematically. In this work four crude extracts, including n-hexane- (IBH), 95% MeOH- (IBM), n-BuOH- (IBB), and H₂O-soluble (IBW) fractions, were prepared by fractionation of a methanolic extract of purple I. batatas leaves. Twenty-four pure compounds 1-24 were then isolated by various chromatographic techniques and their structures identified from NMR and MS data. Glucose uptake assays in differentiated 3T3-L1 adipocytes and rat primary hepatocytes, as well as western blot analysis, were carried out to evaluate the antidiabetic activity of this species. The IBH crude fraction, with methyl decanoate (22) as a major and active compound, showed the greatest effect on glucose uptake, most likely via activation of Glut4 and regulation of the PI3K/AKT pathway. Quercetin 3-O-β-d-sophoroside (1), quercetin (3), benzyl β-d-glucoside (10), 4-hydroxy-3-methoxybenzaldehyde (12), and methyl decanoate (22) could be important components contributing to the antidiabetic effects. We conclude that purple I. batatas leaves have potential as an antidiabetic plant source and the active constituents 1, 3, 10, 12, and 22 are promising lead candidates for future investigation.

Gan-Lu-Yin Inhibits Proliferation and Migration of Murine WEHI-3 Leukemia Cells and Tumor Growth in BALB/C Allograft Tumor Model

The aim of this study was to explore the antitumor effect of Gan-Lu-Yin (GLY), a traditional Chinese herbal formula, on leukemia. Ethanolic extract of GLY was applied to evaluate its regulatory mechanisms in proliferation, migration, and differentiation of WEHI-3 leukemic cells as well as antitumor effect on BALB/c mice model. The results showed that GLY markedly reduced cell proliferation and migration with induced differentiation of WEHI-3 cells. The expression level of phosphorylated FAK, Akt, ERK1/2, and Rb was decreased p21 expression while level was increased in WEHI-3 treated with GLY. The results of cell cycle analysis revealed that GLY treatment could markedly induce G1 phase arrest and decrease cell population in S phase. Moreover, experimental results demonstrated that GLY decreased the protein expression and enzyme activity of MMP-2 and MMP-9. GLY treatment also reduced WEHI-3 leukemic infiltration in liver and spleen and tumor growth in animal model. Accordingly, GLY demonstrated an inhibitory effect on tumor growth with a regulatory mechanism partially through inhibiting FAK, Akt, and ERK expression in WEHI-3 cells. GLY may provide a promising antileukemic approach in the clinical application.

Effects of orexin A on proliferation, survival, apoptosis and differentiation of 3T3-L1 preadipocytes into mature adipocytes

Metabolic activities of orexin A (OXA) in mature adipocytes are mediated via PI3K/PKB and PPARγ. However, the effects of OXA on preadipocytes are largely unknown. We report here that OXA stimulates the proliferation and viability of 3T3-L1 preadipocytes and protects them from apoptosis via ERK1/2, but not through PKB. OXA reduces proapoptotic activity of caspase-3 via ERK1/2. Inhibition of ERK1/2 prevents the differentiation of preadipocytes into adipocytes. Unlike insulin, neither short-term nor prolonged exposure of 3T3-L1 preadipocytes to OXA induces preadipocyte differentiation to adipocytes, despite increased ERK1/2 phosphorylation. Unlike insulin, OXA fails to activate PKB, which explains its inability to induce the differentiation of preadipocytes.