- L-cysteine supplementation lowers blood glucose, glycated hemoglobin, CRP, MCP-1, and oxidative stress and inhibits NF-kappaB activation in the livers of Zucker diabetic rats. Jain, S.K., Velusamy, T., Croad, J.L., Rains, J.L., Bull, R. Free Radic. Biol. Med. (2009)