Spirogyra neglecta inhibits the absorption and synthesis of cholesterol in vitro

Abstract

BackgroundSpirogyra neglecta (SN) has many nutritional benefits and it is commonly used to ameliorate different human conditions including inflammation, gastric ulcer, hyperglycemia, and hyperlipidemia. However, the mechanism of the hypocholesterolemic effect of SN still remains unclear. Therefore, the present study was aimed to evaluate the effect of SN extract particularly on cholesterol absorption and synthesis mechanisms.MethodsFor cholesterol absorption, the uptake of cholesterol was measured by using tritium radiolabeling of cholesterol in Caco-2 cells. Bile acid binding, micelles size, and cholesterol solubility were analyzed in in vitro assays, while cholesterol synthesis was evaluated by using a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase assay kit.ResultsSN extract was found to decrease cholesterol uptake in Caco-2 cells and decreased the solubility of cholesterol in micelles. The SN extract bound to taurocholate, taurodeoxycholate, and glycodeoxycholate bile acids, and increased micelles size. SN has also demonstrated an inhibitory effect on HMG-CoA reductase (HMGR) enzymatic activity. For further experimentation, the treatment combination of SN and ezetimibe (0.04 mg/mL) showed a greater significant reduction in cholesterol uptake than the extract alone.ConclusionThese observations suggested that inhibitory cholesterol absorption effects of SN could be mediated through the modulation of size and solubility of cholesterol micelles, resulting in interference of cholesterol uptake. In addition, SN inhibited the rate limiting step of cholesterol synthesis. This study provides supporting evidence for the potential usage of SN as a cholesterol lowering agent.

Phenolic Profile of Nipa Palm Vinegar and Evaluation of Its Antilipidemic Activities

“…Pancreatic cholesterol esterase is an enzyme which hydrolyses cholesterol esters, so inhibition of pancreatic cholesterol esterase can reduce cholesterol absorption and may be useful for therapeutics for controlling cholesterol [ 25 ]. Moreover, the reduction of micelle formation is a target for lowering blood cholesterol level [ 21 ]. This study evaluated nipa palm vinegar for its total phenolic content and the presence of phenolic compounds as well as determined its ability to inhibit pancreatic lipase, inhibit cholesterol esterase, and inhibit cholesterol micellization.…”

“…Cholesterol micelles served as a model system for in vitro cholesterol micellization and were prepared according to a previous method [ 21 ]. In brief, the micelle solution (2 mM cholesterol, 1 mM oleic acid, and 2.4 mM phosphatidylcholine) was dissolved in methanol and then dried under nitrogen.…”

<i>Spirogyra neglecta</i> Aqueous Extract Attenuates LPS-Induced Renal Inflammation

“…SNE was dissolved in sterile water and administered orally by gavage once daily for 14 d as previously report. 29) The protocol of LPS-induced inflammation is summarised in Table 1.…”

“…27) In vivo studies indicated that this species has several beneficial effects, including anti-gastric ulcer, antihyperglycaemia and anti-hyperlipidaemia. 28,29) However, the information concerning effect of SNE on LPS-induced renal inflammation and its mechanisms remain unclear. This study, therefore, aimed to determine the effect of SNE on renal function, renal organic anion and cation transporter function and its mechanisms involved in experimental LPS-induced inflammation in rats.…”

Effect of lemongrass water extract supplementation on atherogenic index and antioxidant status in rats

“…Phenolic compounds in the CCW extract were further quantitated by high-performance liquid chromatography with diode array detection and a mass spectrometry detector (HPLC-DAD/MSD) (8). Briefly, phenolic compounds were separated using an Agilent 1100 series HPLC system (Agilent Technologies, Germany), equipped with a LiChroCART Stainless Steel Purospher STAR RP-18E column (150 mm × 4.6 mm, particle size 5 μm) (Merck, Germany) and a diode array detector recording at 270, 330, 350 and 370 nm.…”