Neuroprotective effects of sesamin and sesamolin on gerbil brain in cerebral ischemia.

Sesamin and sesamolin, abundant lignans found in sesame oil, have been demonstrated to possess several bioactivities beneficial for human health. Excess generation of nitric oxide in lipopolysaccharide-stimulated rat primary microglia cells was significantly attenuated when they were pretreated with sesamin or sesamolin. The neuroprotective effect of sesamin and sesamolin was also observed in vivo using gerbils subjected to a focal cerebral ischemia induced by occlusion of the right common carotid artery and the right middle cerebral artery. Repeated treatment of sesamin or a crude sesame oil extract containing both sesamin and sesamolin significantly reduced the infarct size, visualized via 2,3,5-triphenyltetrazolium chloride staining, by approximately 50% when compared with the control group. These results suggest that sesamin and sesamolin exert effective neuroprotection against cerbral ischemia.

Sesamin inhibits lipopolysaccharide-induced cytokine production by suppression of p38 mitogen-activated protein kinase and nuclear factor-kappaB.

Sesame seed oil increases the survival after cecal ligation and puncture in mice and the increased IL-10 levels with non-lethal lipopolysaccharides (LPS) challenge. We showed that sesamin and sesamolin, major lignans of sesame oil, regulated LPS-induced nitric oxide production in the murine microglia and BV-2 cell line. In this study, we studied the effect of sesamin on cytokine production by LPS stimulation. The result showed that sesamin significantly inhibited LPS-stimulated IL-6 mRNA and protein, and to a lesser degree TNF-alpha, in BV-2 microglia. Sesamin and sesamolin also reduced LPS-activated p38 mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-kappaB activations. Furthermore, SB203580, a specific inhibitor of p38 MAP kinase, specifically inhibited LPS-induced IL-6 production. These results suggest that sesamin inhibited LPS-induced IL-6 production by suppression of p38 MAPK signal pathway and NF-kappaB activation.

Enhanced methionine and cysteine levels in transgenic rice seeds by the accumulation of sesame 2S albumin.

A chimeric gene encoding a precursor polypeptide of sesame 2S albumin, a sulfur-rich seed storage protein, was expressed in transgenic rice plants under the control of the glutelin promoter with the aim of improving the nutritive value of rice. Rice grains harvested from the first generation of ten different transformed lines inherited the transgene, and the accumulated sesame 2S albumin was presumably processed correctly as its mature form in sesame seed. This transgene was specifically expressed in maturing rice seeds with its encoded sesame 2S albumin exclusively accumulated in the seeds. The crude protein content in rice grains from five putative homozygous lines was increased by 0.64-3.54%, and the methionine and cysteine contents of these transgenic rice grains were respectively elevated by 29-76% and 31-75% compared with those of wild-type rice grains.