Oxidative stress• Estradiol boosts the expression of Nrf2 and its associated antioxidant  enzymes, thereby reducing oxidative stress damage and inflammatory  reactions.• Nrf2 knockout results in a decrease in the abundance of the probiotic L.  murinus in AOM/DSS male mice.• In the presence of high oxidative stress, neuroglobin interacts with  cytochrome C to inhibit the subsequent apoptotic process, thereby  counteracting the pro-apoptotic impact of estradiol. This evidence concerns the gene CYCS and infectious otitis media.