Curcumin Trinicotinate Could Reduce The Abundance Of Beta-amyloid In Brain Of High-fat-diet Rats:Involving In Idol-LDLR Pathway In Brain

[Background and Objective]High-fat diet(HFD)induces higher content of beta-amyloid(Aβ)in brain.Curcumin Trinicotinate(CurTn)has obvious effect on lipid.The low-density lipoprotein receptor(LDLR),which could be ubiquitined and degradated by Idol,decreases the content of Aβ in brain.CurTn can regulate the Idol-LDLR pathway in the liver,decreasing the richness of Idol and increasing the abundance of LDLR.Therefore,we explored whether CurTn exerts reduction of Aβ in the brain of HFD rats and whether Idol-LDLR pathway in brain is involved this role of CurTn.It could provide a new idea for the prevention and treatment of cognitive dyfunction caused by the increase of Aβ in the brain.[Methods]Male Wistar rats adaptively fed for one week were randomly divided into five groups named normal diet group,high fat diet group,high fat diet group + 50 mg/kg/d CurTn,high fat diet group + 100 mg/kg/d CurTn,high fat diet group + 150 mg/kg/d CurTn.Regardless of normal diet group,high fat diet group and CurTn-treated group were injected with a large dose of vitamin D3(600000 IU/kg)for one time on the first day via intraperitoneal pathway.After sacrifaction of Wistar rats fed for eight weeks,the contents of Aβ40 and Aβ42 in brain of Wistar rats were detected by Aβ ELISA kit,while the expression of Idol and LDLR were detected by Western blotting.[Results] 1.CurTn reduced the contents of Aβ40 and Aβ42 in brain of HFD-exposed Wistar rats.The results of ELISA indicated that the contents of Aβ40 and Aβ42 in the brain of Wistar rats in the high fat diet group increased highly compared to the normal diet group(P < 0.05).However,the contents of Aβ40 and Aβ42 in the brain of Wistar rats exposed to high fat diet were reduced by treatment with 100 mg/kg/d and 150 mg/kg/d CurTn(P < 0.05).2.CurTn decreased the abundance of Idol and improved the expression of LDLR in brain of HFD-exposed rats.1)CurTn decreaded the abundance of Idol in brain of HFD-induced rats.The result of Western blotting showed that the expression of Idol in the brain of Wistar rats in the high fat diet group increased clearly compared to the normal diet group(P < 0.01).However,the expression of Idol in the brain of Wistar rats exposed to high fat diet was significancely decreased by treatment with 100 mg/kg/d and 150 mg/kg/d CurTn(P < 0.05).2)CurTn improved the abundance of LDLR in brain of HFD-induced rats.The results of Western blotting showed that when compared with the normal diet group,the abundance of LDLR in the brain of Wistar rats decreased in the high fat group(P < 0.05).However,the content of LDLR in the brain of HFD rats was rised by treatment with 100 mg/kg/d and 150 mg/kg/d CurTn(P < 0.01).[Conclusion] CurTn reduces the abundance of Aβ in the brain of HFD-treated rats,which involves in regulation of Idol-LDLR pathway in the brain.