Effect of NADPH oxidases inhibition on the development of interstitial fibrosis in unilateral ureter obstruction rats / 中华肾脏病杂志

ABSTRACT

Objective To clarify whether the NADPH oxidases (NOXs) family contributed to the reactive oxygen species (ROS) production and subsequent interstitial fibrosis in unilateral ureter obstruction (UUO) rats.Methods Male Wistar rats were randomly divided into sham operation group (n =8),sham operation + apocynin treatment group (n =8),UUO operation group (n =8) and UUO operation+apocynin treatment group (n =8).Either vehicle or apocynin (100 mg/kg per day) were given by gavage for 7 days after surgery.Rats were sacrificed at 7th day.ELISA was used to detect the activity of superoxide dismutase (SOD) and catalase (CAT),and the level of 8-iso-prostaglandin F2alpha (8-isoPGF2α) in renal tissue.Western blotting was used to detect the protein expressions of NADPH oxidase subunit NOX2 and NOX4,α-smooth muscle actin(α-SMA),collagen Ⅰ (COL-Ⅰ) and the level of ERK1/ 2 phosphorylation (p-ERK1/2).Results UUO rats with vehicle displayed increased oxidative stress,as measured by renal tissue 8-iso-PGF2α,accompanied with increased renal expression of NADPH oxidases (NOX2,1.5-fold and NOX4,1.7-fold,respectively),compared with sham-operated rats (P ＜0.05).Furthermore,vehicle treated UUO rats showed increased renal COL-Ⅰ and α-SMA levels,compared with sham-operated rats (P ＜ 0.05).ERK1/2 was also activated as detected by p-ERK1/2 expression in UUO rats with vehicle (P ＜ 0.05).Apocynin treatment significantly decreased renal tissue 8-iso-PGF2α level and expressions of NOX2 (-28.7％) and NOX4 (-31.0％) in UUO rats,respectively,compared with vehicle treated rats (P ＜ 0.05).And significant decrease of COL-Ⅰ (-26.4％) and α-SMA expression (-80.0％) were also observed (P ＜ 0.05).The activation of ERK1/2 in UUO rats was greatly inhibited by apocynin treatment (P ＜ 0.01).Despite the pronounced dysregulation of pro-oxidative NOXs family,no compensatory increase of antioxidative enzyme activities occurred.Conclusion The NOXs family contributes largely to the production of ROS and subsequent interstitial fibrosis after ureter ligation,and inhibition of the NOXs family may be a choice for preventing interstitial fibrosis.