Extruded Amaranth (Amaranthus hypochondriacus) Hydrolysates Showed Potential Anti‐atherosclerotic Effect on THP‐1 Human Cells

Abstract

The aim of this study was to compare the anti‐atherosclerotic effect of unprocessed amaranth hydrolysate (UAH) and extruded amaranth hydrolysate (EAH) in lipopolysaccharide (LPS)‐induced human THP‐1 cells by protein expression, immunocytochemistry and confocal microscopy. Amaranth was extruded in a single screw extruder at 125 °C and 130 rpm. Unprocessed and extruded amaranth flours were hydrolyzed with pepsin and pancreatin and freeze dried until use. THP‐1 human cells, derived from acute monocytic leukemia, were treated with both hydrolysates at 1 mg/mL for 24 h; LPS was applied to induce inflammation. UAH and EAH inhibited the expression of interleukins related with the atherosclerotic process such as interleukin‐4, interleukin‐6, among others. Likewise, UAH and EAH inhibited the expression and production of MCP‐1 and tumor necrosis factor‐α (TNF‐α), respectively. Western blot analysis showed that EAH inhibited LOX‐1 (27%), ICAM‐1 (28%) and MMP‐9 (19%) expression, important protein markers in atherosclerosis. By confocal microscopy, EAH led to a reduction of 58, 52 and 79% for LOX‐1, ICAM‐1 and MMP‐9, respectively. In conclusion, extruded amaranth hydrolysates showed potential anti‐atherosclerotic in LPS‐induced THP‐1 human macrophage‐like cells, reducing expression of proteins associated with LOX‐1 signaling, perhaps attributed to the formation of bioactive peptides during the extrusion process