Down-Regulation of Genes Related to Photoaging and Inflammation in UVB-Irradiated Mice Premature Skin Photoaging by Linoleic Acid-Rich Tempeh Oil

In a study from June 19, 2019, researchers investigated the effects of linoleic acid-rich tempeh oil, extracted from white and black soybean tempeh, on UVB-induced premature skin photoaging in mice. The study involved groups of mice that were exposed to UVB radiation for 4 weeks to induce photoaging and were then orally supplemented with tempeh oil at doses of 100 and 300 mg/kg, alongside a negative control, a positive control, and an omega-3 standard. The tempeh oil, which was found to contain high levels of linoleic acid (52.3% in white tempeh oil and 85.69% in black tempeh oil), showed efficacy in improving tissue damage and increasing hair follicle proliferation. Furthermore, the oil significantly down-regulated the expression of genes associated with photoaging and inflammation, such as MMP-1, MMP-3, MMP-9, COX-2, and iNOS, with a notable impact on the MMP-9 gene. The study concluded that tempeh oil could be a promising photoprotective ingredient for use in nutraceuticals and cosmeceuticals aimed at protecting against skin photoaging.