Sesame oil attenuates nutritional fibrosing steatohepatitis by modulating matrix metalloproteinases-2, 9 and PPAR-γ.

Sesame oil is a nutrient-rich antioxidant popular in alternative medicine. It contains sesamin, sesamol, and sesamolin, all of which contribute to its improved liver function in various animal model studies. However, its effect on nutritional fibrosing steatohepatitis is unclear. We investigated therapeutic sesame oil on matrix metalloproteinases-2, 9 (MMP-2, 9) in nutritional fibrosing steatohepatitic mice. C57BL/6 J mice were fed with methionine-choline deficient (MCD) diet for 35 days to induce fibrosing steatohepatitis. Sesame oil was treated from 29-35th day. Body weight, steatosis, aspartate transaminase, alanine transaminase, peroxisome proliferator-activated receptor (PPAR)-γ, α-smooth muscle actin (α-SMA), MMP-2, 9, and tissue inhibitor of matrix metalloproteinases (TIMP)-1 were assessed after 35 days. All tested parameters except TIMP-1 and PPAR-γ were higher in MCD fed mice than in normal control mice. Mice fed with MCD diet for 4 weeks showed severe liver injury with steatosis, necrotic-inflammation, and fibrosis. In sesame-oil (4 ml)-treated mice, all tested parameters except TIMP-1, α-SMA, and PPAR-γ were significantly attenuated compared with MCD fed mice. Sesame oil inhibited MMP-2, 9 activities, but up-regulated TIMP-1 expression in MCD fed mice. In addition, a histological analysis of liver tissue samples showed that sesame oil provided significant protection against fibrosis. We conclude that therapeutic sesame oil protects against fibrosing steatohepatitis by inhibiting MMP-2, 9 activities, up-regulating TIMP-1 expression, and PPAR-γ.