Withaferin-A down-regulate enterohepatic circulation of bile acids: An insight from a hyperlipidemic rat model Pooja Acharya a, b , Parvati Huded a , Sadashivaiah Bettadahalli a , Mehrdad Zarei a , Vinayak Uppin a, b , Nayana Venugopal a , Ramaprasad Ravichandra Talahalli a, b, * a Dept. of Biochemistry, CSIR-Central Food Technological Research Institute, Mysore, 570020, Karnataka, India b Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, Uttar Pradesh, India ARTICLE INFO Keywords: Apical sodium-dependent bile acid transporter Cholesterol 7-α hydroxylase HMG-CoA Hyperlipidemia Withaferin-A ABSTRACT Hyperlipidemia is a metabolic abnormality in both young and aged populations across the world. Withaferin-A (WT) present in Withania somnifera (Indian ginseng) has been studied by many investigators for their therapeu- tic potentials. However, their effects on bile acid (BA) metabolism, that play a significant role in lipid homeostasis under hyperlipidemia has not been studied. This study explores the modulatory potential of WT on BA meta- bolism in young and aged hyperlipidemic rats. Hyperlipidemia was induced by feeding lard fat (35g/100g diet, HF) for 60 days. Withaferin-A (2.5 mg/kg diet) was fed to assess its effect on lipid metabolism and enterohepatic circulation of BA. In both models, compared to HF, WT had significantly (p < 0.05), decreased serum lipids, BA uptake, and HMG-CoA reductase activity, but increased hepatic Cyp7a1, decreased serum BA and increased fecal BA. WT re-regulated hyperlipidemia-induced aberrations in the intestinal uptake, hepatic synthesis, and choles- terol and BA metabolism in both models. 1. Introduction Hyperlipidemia is characterized by an increased level of blood lipids, and it is one of the risk factors for developing cardiovascular disease [1]. Bile acid (BA) sequestrants, in combination with lipid-lowering drugs, are prescribed to address hyperlipidemia [2,3]. Interrupting the intesti- nal bile reclamation by modulating the apical sodium-dependent bile acid transporter (Asbt) is an emerging therapeutic approach [4]. The beneficial use of mainstream lipid-lowering drugs are weakened by side effects [5], and the shortcomings can be overcome by employing phy- tomolecules with medicinal properties [6]. Synthetic molecules that serve as Asbt blockers are under clinical trials [7]. There are FDA-approved drugs of diverse classes such as dihydropyridine calcium channel blockers and HMG-CoA reductase inhibitors, which can qualify as Asbt inhibitors, but they elicit varied physiological responses, with Asbt inhibition occurring only as an auxiliary effect, rather than the primary mechanism [8,9]. Withania sominifera is an Indian traditional medicinal plant, and have been exploited for curing several health complications [10]. Withanolides present in Withania somnifera exhibit versatile therapeutic benefits, including hypoglycemic and hypolipi- demic [11,12], neuroprotective [13], and cytotoxic activity [14,15]. It has been demonstrated that withanolides favorably modulate blood lipids in mildly hypercholesterolemic human subjects [16]. Withaferin-A (WT) is the first member of the withanolide class of ergostane with car- dioprotective, anti-inflammatory, and immunomodulatory properties [17,18]. However, there are no reports on the mechanism by which WT normalizes hyperlipidemia, especially by the intervention of enter- ohepatic circulation of BA and its transporters. In this study, we investigated the effect of WT on the enterohepatic circulation of BA in young and aged hyperlipidemic rats, to understand the efficacy of WT in the modulation of bile acid metabolism. Our study showed that WT mitigates aberrations in the lipid profile caused by hyperlipidemia by modulating BA metabolism in both young and aged conditions, with similar efficacy. Further, the benefits observed in the young and aged hyperlipidemic rat model need to be validated in human subjects to exploit WT as a standalone or adjunct therapy in the treatment of hyperlipidemia. Abbreviations: Asbt, apical sodium-dependent bile acid transporter; BA, bile acids; Cyp7a1, cholesterol 7-α hydroxylase; HF, high-fat; HMG-CoA, 3-hydroxy-3- methyl-glutaryl-coenzyme A; WT, Withaferin-A. * Corresponding author. Dept. of Biochemistry, CSIR-Central Food Technological Research Institute, Mysore, 570020, Karnataka, India. E-mail address: ramaprasad@cftri.res.in (R.R. Talahalli). Contents lists available at ScienceDirect Journal of Agriculture and Food Research journal homepage: www.journals.elsevier.com/journal-of-agriculture-and-food-research/ https://doi.org/10.1016/j.jafr.2020.100035 Received 20 February 2020; Received in revised form 13 March 2020; Accepted 13 March 2020 2666-1543/© 2020 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Journal of Agriculture and Food Research 2 (2020) 100035