The role of NADPH oxidase in taurine attenuation of Streptococcus uberis-induced mastitis in rats

- The ameliorating effects of taurine on NADPH oxidase in S. uberis mastitis were defined.
- T-AOC levels and SOD activities decreased, MDA levels increased after S. uberis infusion.
- Concentrations of IL-1β and IL-6 were also decreased by taurine administration.
- Taurine has the ability of regulating redox condition of organism.

In order to evaluate the role of taurine on the oxidative stress mediated by NADPH oxidase in Streptococcus uberis-induced (S. uberis) mastitis, rats were administered daily (per os) 100 mg/kg of taurine (group TS) or an equal volume of physiological saline (group CS) from gestation day 14 until parturition. Seventy-two hours after parturition, approximately 100 cfu of S. uberis was infused into each of 2 mammary glands. Pretreatment with taurine significantly decreased mRNA and protein expression of p47phox and p22phox in mammary tissues. The total anti-oxidation capability (T-AOC) levels and superoxide dismutase (SOD) activities decreased, while malondialdehyde (MDA) levels increased both in mammary tissues and serum of rats with intramammary S. uberis infusion. Gavage administration of taurine moderated this change. Concentrations of interleukin-1β (IL-1β) and IL-6 in mammary glands decreased as a result of taurine administration. Significant differences (P < 0.05) were present at 48 and 72 h post S. uberis-infusion (PI) for IL-1β and 72 h PI for IL-6. Our data indicate that, in S. uberis-induced mastitis, taurine has the ability of regulating redox conditions which leads to the suppression of oxidative stress and secretion of proinflammatory cytokines. This phenomenon may be ascribed to taurines's ability to inhibit the expression of NADPH oxidase.