THE INHIBITORY EFFECT OF RAMBUTAN PEEL EXTRACT TO THE Igf-1 AND Igf-1r EXPRESSION IN OBESE RATS VISCERAL FAT
Abstract
The activation of Insulin Like Growth Factor-1 (Igf-1) to its receptor (Igf-1r) plays an important role in the process of adipogenesis. The inhibition of Igf-1 and its receptor at the early process is the precise step for the therapy of obesity. This study used obese rats treated with ellagic acid and Rambutan Peel Extract (RPE) 30mg/kgbw dose. The Igf-1 and Igf-1r expression in visceral fat tissue was observed using immunofluorescence double staining, which confirmed later by western blotting. The results reveal that the use of RPE30mg/kg BW on obese rats model can provide inhibitory effect on the expression of igf-1 and igf-1r as in a normal rat. The expression of igf-1 and its receptor highest in obese rats and the lowest expression in obese rats which were treated with ellagic acid. The reduced expression of igf-1 and its receptor will reduce ERK1/2 and PPAR expression in adipogenesis signaling cascade and in turn inhibits adipogenesis.
Keywords: Igf-1, Igf-1r, Rambutan Peel Extract (RPE)
References
Buehlmeyer, K. 2007. IGF-1 gene expression in rat colonic mucosa after different exercise volumes. 434–440.
Campos, K. E., G.T. Volpato, I.M.P. Calderon, M.V.C. Rudge and D.C. Damasceno. 2008. Effect of obesity on rat reproduction and on the development of their adult offspring. Braziian Journal of Medical and Biological Research 41, 122–125.
Firdausi, L., M.R. Indra, and F. Fatchiyah. 2012. Binding Inhibition Between Igf-1r and Igf-1 by Catechin of Black Tea. The Journal of Tropical Life Science 2, 132–135.
Gregoire, F. M., Smas, C. M., and H.E.I.S. Sul. 1998. Understanding Adipocyte Differentiation. 78, 783–810.
Holly, J., M. Sabin, C. Perks, and J. Shield. 2006. Literature review. Matabolic Syndrome and Related Disorder 4: 43-50.
Kloting, N. 2008. Autocrine IGF-1 Action in Adipocytes Controls Systemic. Diabetes 57, 2074–2082.
Kondo, T. 2003. Knockout of insulin and IGF-1 receptors on vascular endothelial cells protects against retinal neovascularization. 111, 1835–1842.
Lin, J., M.A. Della-fera, C.A. Baile and A. Clifton. 2005. Inhibits Adipogenesis and Induces Apoptosis in 3T3-L1 Adipocytes.13.
Marques, B. G. 2012. Insulin-like growth factor I mediates high-fat diet-induced adipogenesis in Osborne-Mendel rats metabolism regulation Insulin-like growth factor I mediates high-fat diet-induced adipogenesis in Osborne-Mendel rats. Physiol, Am J Integr, Regul 278, R654 – R662.
Min, S. Y. 2012. Cocoa polyphenols suppress adipogenesis in vitro and obesity in vivo by targeting insulin receptor. International Journal of Obesity 1–9.doi:10.1038/ijo.2012.85
Onkogi, S., C. Dhuangrat, S. Anuchpeed, S. Tachakitturungrod. 2007. Sombat Chowwanapoopahn Comparisson of Antioxidants Capasities and Cytotoxicities of Certain Fruit Peel. Jurnal of Medical Science 103.
Ross, S.E. 1999. Glycogen Synthase Kinase 3 Is an Insulin-Regulated C / EBP/ Kinase. 19, 8433-8441.
Thitilertdecha, N., A. Teerawutgulrag, J.D. Kilburn, N. Rakariyatham. 2010. Identification of Major Phenolic Compounds from Nephelium lappaceum L. and Their Antioxidant Activities. Molecule 15, 1453–1465.
Unno, T. 2009. Dietary tea catechins increase fecal energy in rats. Journal of nutritional science and vitaminology 55, 447–51.
Viswakarma, N. 2010. Coactivators in PPAR-Regulated Gene Expression. PPAR Research 2010, 1–22.