Intervention Of Astaxanthin On Ochratoxin A Induced Nephrotoxicity In Broilers

Ochratoxin A（OTA）is an important mycotoxin with a wide range of existence.OTA causes great harm to human and animal health by polluting food and feed.In previous reports,the kidney is the main target organ of OTA,and a certain dose of OTA can lead to kidney injury.Astaxanthin（ASX）is a naturally occurring carotenoid with strong antioxidant capacity.ASX can protect cells from oxidative damage,so it is speculated that ASX has a certain intervention effect on cellular oxidative stress caused by OTA.Renal injury caused by many reasons can cause endoplasmic reticulum stress,but whether the toxic effect of OTA on kidney can cause endoplasmic reticulum stress has not been reported.Purpose:This experiment was to explore whether ASX could intervene the renal injury induced by OTA in Broilers by inhibiting the endoplasmic reticulum stress pathway.Method:Sixty 1-day-old white feather broilers were random Ly divided into control group（CON,0.1 m L Na HCO₃solution）,challenge group（OTA,5.0 mg/kg OTA）,antidote group（ASX,100 mg/kg ASX）and combined detoxification group（5.0 mg/kg OTA+100mg/kg ASX）.The renal injury effect of OTA and the intervention effect of ASX were detected by measuring the body weight,renal organ coefficient,histopathological section,transmission electron microscope,renal function index,serum biochemical index,real-time fluorescence quantitative PCR and Western blot.Result:（1）ASX can inhibit the decline of body weight and organ coefficient of broilers caused by OTA,and improve the pathological changes such as renal glomerular atrophy,renal tubular swelling and vacuolar degeneration.（2）ASX can inhibit the increase of urea nitrogen（BUN）and creatinine（CRE）in serum caused by OTA.（3）ASX can inhibit the decrease of total antioxidant capacity（T-AOC）,superoxide dismutase（SOD）,catalase（CAT）activity and reduced glutathione（GSH）content in serum caused by OTA,and prevent the increase of malondialdehyde（MDA）.（4）The results of real-time fluorescence quantitative PCR showed that ASX could inhibit the increase of GRP78、GRP94、ATF4、ATF6、CHOP、PERK、el F-2α、Caspase-3、Caspase-12 m RNA expression caused by OTA and prevent the decrease of Bcl-2 m RNA expression.（5）Western blot results showed that ASX could inhibit the increased protein expression of GRP78,ATF6 and CHOP caused by OTA.Conclusion:ASX can significantly improve the renal function of broilers poisoned by OTA.Its mechanism may be related to inhibiting endoplasmic reticulum stress,improving renal antioxidant capacity and inhibiting endoplasmic reticulum stress-mediated apoptosis.