Hulless barley polyphenol extract inhibits adipogenesis in 3T3-L1 cells and obesity related-enzymes

Abstract

Obesity is characterized by excessive lipid accumulation, hypertrophy, and hyperplasia of adipose cells. Hulless barley (Hordeum vulgare L. var. nudum Hook. f.) is the principal crop grown in the Qinghai-Tibet plateau. Polyphenols, the major bioactive compound in hulless barley, possess antioxidant, anti-inflammatory, and antibacterial properties. However, the anti-obesity effect of hulless barley polyphenol (HBP) extract has not been explored. Therefore, the current study assessed the impact of HBP extract on preventing obesity. For this purpose, we evaluated the inhibitory effect of HBP extract against obesity-related enzymes. Moreover, we investigated the effect of HBP extract on adipocyte differentiation and adipogenesis through 3T3-L1 adipocytes. Our results demonstrated that HBP extract could inhibit α-amylase, α-glucosidase (α-GLU), and lipase in a dose-dependent manner. In addition, HBP extract inhibited the differentiation of 3T3-L1 preadipocytes by arresting the cell cycle at the G0/G1 phase. Furthermore, the extract suppressed the expression of adipogenic transcription factors such as peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), regulating fatty acid synthase (FAS), fatty acid-binding protein 4 (FABP4), and adipose triglyceride lipase (ATGL). It was also observed that HBP extract alleviated intracellular lipid accumulation by attenuating oxidative stress. These findings specify that HBP extract could inhibit obesity-related enzymes, adipocyte differentiation, and adipogenesis. Therefore, it is potentially beneficial in preventing obesity.

Microbial fermentation of blue honeysuckle ( Lonicera caeruleaL.) polyphenol promotes insulin secretion and intervenes in obesity by promoting short-chain fatty acids production

“…Therefore, extracting substances from natural plants that inhibit α-amylase and α-glucosidase activities is of considerable significance for obesity prevention and treatment [58]. In this study, the evaluation results of the in vitro hypoglycemic effect of polyphenols revealed that BHP had the strongest inhibitory effect on α-amylase, and polyphenols exerted a dose-dependent inhibitory effect on α-amylase and α-glucosidase, which is consistent with the results of Deng et al [54]. These researchers found that the hulless barley polyphenol extract had certain dose-dependent inhibitory effects on ɑ-amylase and ɑ-glucosidase.…”

“…When α-amylase and α-glucosidase activities are inhibited, circulating glucose levels are maintained by reducing blood glucose absorption [7,54]. Existing enzyme inhibitors such as acarbose, miglitol, and vogliose are used to inhibit the activity of the aforementioned enzymes.…”

“…ɑ-Amylase and ɑ-glucosidase can decompose starch and glycogen, and glucose absorption is delayed with the inhibition of their enzyme activities, which then controls obesity. Natural phenolic compounds can non-specifically inhibit ɑ-amylase and ɑ-glucosidase activities [7,54]. Therefore, to preliminarily evaluate whether BHPs can intervene in obesity, their ability to inhibit ɑ-amylase and ɑ-glucosidase activities was measured in vitro (Fig.…”

Heterologous expression and enzymatic characteristics of sulfatase from Lactobacillus plantarum dy-1

“…The hypoglycemic and lipid-lowering functions of phenolic acid in vitro were achieved by inhibiting amylase and lipase. The impact of α-amylase and lipase on the release of bound phenolic acids was determined using a method described by Deng et al 25 In summary, 50 μL of serially diluted bound phenolic acid (50–300 μg GAE mL −1 ), 200 μL of the enzyme solution (10 U mL −1 in the same phosphate buffer), and 550 μL of phosphate buffer were mixed in preincubated tubes and incubated for 5 min at 37 °C. After the addition of 200 μL of 0.5% gelatinized starch solution (w/v), the tubes were further incubated at 37 °C for 10 min.…”

Influence of Polyphenols on Adipose Tissue: Sirtuins as Pivotal Players in the Browning Process

“…Micromolar concentrations of resveratrol prevented preadipocyte differentiation, promoted mature adipocyte lipolysis [117], and decreased lipid accumulation in murine (3T3-L1) and human (SGBS) adipocytes [118]. Both isolated polyphenols (e.g., apigenin, hesperidin, myricetin, quercetin, resveratrol) and polyphenol extracts inhibited adipogenesis through modulation of PPAR-γ expression [117,[119][120][121][122][123], but other targets may be involved in the pharmacology of natural polyphenols. For instance, naringenin and naringin (20-100 µM) decreased triglyceride and lipid accumulation in 3T3-L1 cells by phosphorylating AMPK and acetyl-CoA carboxylase (ACC) [124], while resveratrol (50-100 µM) reduced lipid droplets in cultured adipocytes by decreasing AMPK and ACC levels [118].…”