NOS2 and in situ carcinoma: CIS damages testicular tissue and reduces sperm production through increasing oxidative stress and inducing apoptosis and upregulations of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), while Ginkgo biloba reduces these oxidative and apoptosis actions of CIS in testis [25].