Modulation of Keap1-Nrf2-ARE signaling pathway by oxyresveratrol,a derivative of resveratrol from grape skin

Grape skin,one of the by-products of grape processing,is rich in oxyresveratrol and other bioactive compounds.Oxyresveratrol is a polyphenolic non-flavonoid with anti-inflammatory and anti-aging properties among other biological activities,but little research has been done on its antioxidant mechanism.This study aims to evaluate the regulation of oxyresveratrol on Keap1-Nrf2-ARE signaling pathway.Firstly,oxyresveratrol in grape skin was detected by HPLC-MS/MS,and then its interaction mechanism with Keap1 was investigated by molecular docking.The result of Western blot further confirmed that oxyresveratrol can bind with Nrf2 to induce its nuclear translocation.The Luciferase reporter gene analysis revealed the agonistic effects of oxyresveratrol on ARE.Oxyresveratrol increased not only the mRNA expression levels of ARE-mediated genes NQO1,HO-1,and GCLM,but also their protein expression levels,suggesting that oxyresveratrol inhibited H2 O2-induced oxidative damage.Therefore,oxyresveratrol can be applied as a potential antioxidant by activating the Keap-Nrf2-ARE signaling pathway.

Using genetic tools to inform conservation of fragmented populations of Asian elephants (Elephas maximus) across their range in China

A herd of 15 Chinese elephants attracted international attention during their 2021 northward trek,motivating the government to propose establishment of an Asian elephant national park.However,planning is hampered by a lack of genetic information on the remaining populations in China.We collected DNA from 497 dung samples from all 5 populations encompassing the entire range of elephants in China and used mitochondrial and microsatellite markers to investigate their genetic and demographic structure.We identified 237 unique genotypes(153 females,84 males),representing 81%of the known population.However,the effective population size was small(28,range 25–32).Historic demographic contraction appeared to account for low haplotype diversity(Hd=0.235),but mod-erate nucleotide and nuclear diversity(π=0.6%,He=0.55)was attributable to post-bottleneck recovery involving recent population expansion plus historical gene exchange with elephants in Myanmar,Lao PDR,and Vietnam.The 5 populations fell into 3 clusters,with Nangunhe elephants differing consistently from the other 4 populations(FST=0.23);elephants from Mengyang,Simao,and Jiangcheng belonged to a single population(henceforth,MSJ),and differed from the Shangyong population(FST=0.11).Interpopulation genetic variation reflected isola-tion by distance and female-biased dispersal.Chinese elephants should be managed as 2 distinct units:Nangunhe and another combining Shangyong and MSJ;their long-term viability will require restoring geneflow between Shangyong and MSJ,and between elephants in China and neighboring countries.Our results have the potential to inform conservation planning for an iconic megafaunal species.