MO610: A Graphene-Based Bioactive Compound Reduces Adipogenesis and Increases Lipolysis Via Integrin-Beta1 Interaction: A New Therapeutical Approach Against Obesity

Abstract

Abstract BACKGROUND AND AIMS Type 2 diabetes and obesity are metabolic disorders related to kidney risk and associated with white adipose tissue (WAT) hypertrophy, which is based in a pro-adipogenic transdifferentiation of the adipocytes and their precursors’ stem cells present in WAT. Several transcription factors are key regulators during this transdifferentiation. The consequence is that adipocytes’ size increases due to the excessive storage of triglycerides (TG) inside the cells. Therapeutic strategies for reducing WAT size may be based in the capacity of increasing lipolysis and reducing adipogenesis. We have previously demonstrated the implication of the extracellular matrix (ECM) mediator integrin beta 1 (INTB1) and intracellular mediation of actin cytoskeleton during obesity (Hatem-Vaquero. J Endocrinol 2017; Cell Physiol Biochem 2020). Here, we demonstrate for the first time the antiobesogenic properties of a new highly biocompatible and bioactive graphene-based product named BioGraph (Llorens-Gámez M. Int J Biol Macromol 2020; Salesa B. Biomedicines 2021), which physicochemical interaction with INTB1 give a great potential as a diagnostic and bioactive therapeutic tool. METHOD Pluripotent c3h10t1/2 cells were differentiated into adipocytes using a specific culture medium. After 7 days of differentiation, the adipocytes were treated for 24 h with a suspension of the graphene derivative BioGraph, developed, registered and patented by Graphenano Medical Care S.L. To determine viability and toxicity on adipocytes, trypan blue and MTT labeling techniques were used. The levels of intracellular TG contained in the lipid droplets were determined by fluorescent labeling with AdipoRed. PPARgamma, CEBP and INTB1 mRNA levels were determined by RT-qPCR. Actin polymerization in the cytoskeleton was quantified by fluorescent phalloidin staining. Active INTB1 quantification (phosphorylated isoform at thr788/9) and total and active lipase HSL (phosphorylated isoform at ser660) were performed by western blot. RESULTS BioGraph is safe and non-toxic on adipocytes in a two-order concentration range. The TG content is reduced in a dose-dependent manner. Adipogenesis markers PPARgamma and CEBP and actin polymerization were reduced after treatment with an intermediate dose. The expression of INTB1 was not modified, but its phosphorylation was increased rapidly after treatment. Lipolysis-main enzyme HSL expression and activity were increased 24 h after treatment. CONCLUSION BioGraph is biocompatible and bioactive on adipocytes. A rapid modulation of INTB1 produces the depolymerization of the cytoskeleton, the reduction of intracellular TG content and the expression of adipogenesis markers, while HSL-mediated lipolysis is increased. We demonstrate for the first time the mechanism followed by a graphene-based material modulating the adipocyte phenotype and behavior. BioGraph may be considered a new anti-obesogenic agent.