ANTI-ATHEROSCLEROSIS EFFECT OF THE HERB SPERANSKIA TUBERCULATA (BUNGE) BAILL

Abstract

The article describes the inhibitory effect of extracts of the herb Speranskia Tuberculata (Bunge) Baill on atherosclerosis of vessels. Crude extracts were prepared using petroleum ether (PE extracts). Subsequently, the dried extracts were dissolved in dimethyl sulfoxide to prepare working solutions with 12.5 to 75 μg/mL concentrations. RAW 264.7 cells, a macrophage cell line, were used as the research object. Atherosclerosis was induced in the cells by incubating oxidised low-density lipoproteins. The study of the influence of PE extract concentration was carried out in two experiments. The first included oil red O staining on macrophages with different concentrations of PE extract added, followed by a spectrophotometric examination of the solutions. Thus, the effect of PE extract concentration on lipid content in cells was investigated. The second method was based on flow cytometry and ended by measuring the intensity of fluorescent cholesterol in the cells of various samples. Cell samples additionally containing only oxidised low-density lipoproteins, as well as cells treated with PE extract and caffeic acid, were compared. PE extracts of Speranskia Tuberculata (Bunge) Baill effectively inhibit the transition from macrophages to foam cells, as shown by labelling foam cells with neutral fat using Oil red O staining. The processes of cholesterol uptake by macrophages were investigated by flow cytometry using fluorescently labelled cholesterol. PE extract minimises cholesterol deposition in macrophages by inhibiting macrophage phagocytosis of cholesterol while promoting the effect of intracellular cholesterol outflux. Thus, the role of PE extracts in regulating the cholesterol balance in macrophages and inhibiting the transformation of macrophages into foam cells has been experimentally proven. Possible mechanisms for realising these effects are proposed.