Effects of Capsaicin on Induction of Apoptosis and Inhibition of Adipogenesis in 3T3-L1 Cells

Abstract

Currently, at the beginning of the 21st century, obesity has become the leading metabolic disease in the world. It is a serious health problem in industrialized countries. Previous research has suggested that decreased preadipocyte differentiation and proliferation and decreased lipogenesis are mechanisms to reduce obesity. In the present study, the effects of capsaicin on the induction of apoptosis and inhibition of lipid accumulation in 3T3-L1 preadipocytes and adipocytes were investigated. The results demonstrated that capsaicin decreased cell population growth of 3T3-L1 preadipocytes, assessed with the MTT assay. Flow cytometric analysis of 3T3-L1 preadipocytes exposed to capsaicin showed that apoptotic cells increased in a time-and dose-dependent manner. Treatment with capsaicin decreased the number of normal cells and increased the number of early apoptotic and late apoptotic cells in a dose-dependent manner. The treatment of cells with capsaicin caused the loss of mitochondria membrane potential (∆Ψm). The induction of apoptosis in 3T3-L1 preadipocytes by capsaicin was mediated through the activation of caspase-3, Bax, and Bak, and then through the cleavage of PARP and the down-regulation of Bcl-2. Moreover, capsaicin significantly decreased the amount of intracellular triglycerides and glycerol-3-phosphate dehydrogenase (GPDH) activity in 3T3-L1 adipocytes. Capsaicin also inhibited the expression of PPARγ, C/EBPR, and leptin, but induced up-regulation of adiponectin at the protein level. These results demonstrate that capsaicin efficiently induces apoptosis and inhibits adipogenesis in 3T3-L1 preadipocytes and adipocytes.

Anti-obesity efficacy of nanoemulsion oleoresin capsicum in obese rats fed a high-fat diet

“…36 In 3T3-L1 adipocytes, red pepper constituents decrease the amount of intracellular TG by inhibiting GPDH activity, which inhibits adipogenesis. 37 In a previous study, one red pepper constituent, capsaicin, also attenuated GPDH activity, resulting in reduced WAT mass and body weight. 36 Consistent with those results, NOC supplementation, in the present study, also led to decreased GPDH activity in WAT, whereas OC did not.…”

Search for New Type of PPARγ Agonist-Like Anti-diabetic Compounds from Medicinal Plants

“…33) Furthermore, capsaicin, a well known transient receptor potential vanilloid type-1 (TRPV1) agonist, was reported to prevent adipogenesis in stimulated 3T3-L1 cells, 33,34) but it induced the up-regulation of adiponectin. 35) On the other hand, the effects of piperine (11), which was reported as a TRPV1 agonist, 36) and related amide constituents on 3T3-L1 cells have not been examined.…”

The Role of Transient Receptor Potential Channels in Metabolic Syndrome

“…Capsaicin activation of TRPV1 in 3T3-L1 preadipocytes reduced adipogenesis by decreasing the activities of peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein (C/EBPα), leptin, intracellular triglycerides, and glycerol-3-phosphate dehydrogenase activity. Furthermore activation of TRPV1 in 3T3-L1 preadipocytes increased apoptosis by activation of caspase-3, pro-apoptotic Bax and Bak, cleavage of poly(ADP-ribose) polymerase (PARP), and downregulation of anti-apoptotic Bcl-2 (15). Capsaicin also activated the serine/threonine kinase, AMP-activated kinase (AMPK), in 3T3-L1 preadipocytes, causing reduced adipogenesis and increased apoptosis (16).…”