Anti-obesity potential of bioactive guided fractions of Annona squamosa linn. leaves extract: a combination of in-vitro, in-vivo and in-silico studies along with profiling of lead compounds by HPTLC MS-MSn method.

Abstract

The antiobesity potential of bioactive fractions derived from Annona squamosa was approached using a combination of in vitro, in silico and in-vivo studies. The study was analyzed to validate and select the potent bioactive fractions of A. squamosa leaves extract through in vitro and in vivo activities targeting obesity. The phytochemical properties of the bioactive fractions were investigated utilizing total flavonoid, total phenolic and total steroidal content. Further, in vitro antioxidant assays such as nitric oxide (NO2), DPPH, ABTS, and Hydrogen peroxide (H2O2) scavenging assays were performed whereas pancreatic lipase, Alpha-amylase and Alpha glucosidase assays were carried out for enzyme inhibition activities. The overall study revealed that fractions F2 and F3 had shown significant in vitro activities targeting obesity. The selected potent fractions (F2 and F3) were orally bio-screened for efficacy in MSG-HFD-induced obese mice at 80mg/kg/bw. The invivo study confirmed that fractions 2 and 3 with a dose of 80mg/kg/bw had a significant potency compared to obese control and standard for various parameters. Body weight and lipid metrics were significantly reduced, and histological examinations revealed considerable beneficial alterations in the organs of the animals. Further HPTLC MS-MSn was used to characterize and identify the major compounds in the potent bioactive fractions, which confirmed the presence of seven major compounds: Ascorbic acid, Gallic acid, Quercetin, β-sitosterol, Stigmasterol, Caffeine and Epigallocatechin gallate. An in silico model was then employed to determine the best binding activity of the identified compound towards the specific receptors targeting obesity, confirming the most effective docking score towards stigmasterol and sitosterol. The in vitro and in vivo studies of derived bioactive fractions of A. squamosa leaves extract revealed a possible therapeutic approach towards anti-obesity activity for the first time.