Study Of The Prevention Of Contrast-Induced Nephropathy By Polysaccharides Of Sargassum Fusiforme Through Antioxidant Capacity

Background and Objective:Contrast-induced nephropathy(CIN)has become one of the most common complications of patients after percutaneous coronary intervention.Its pathogenesis is still unclear and prevention methods are extremely limited.Recent studies have suggested that oxidative stress injury may be involved in the pathogenesis of CIN,so it is very important to study the role of oxidative stress in CIN and find corresponding preventive measures.Sargassum fusiforme has a long history of application in the traditional Chinese medicine of kidney disease treatment,and its main bioactive ingredient is the polysaccharides of sargassum fusiforme(SFP).The purpose of this study was to clarify the correlation between oxidative stress and CIN.To investigate whether SFP have antioxidant activity and thus prevent the effect of renal CIN through antioxidant.Methods:1.Relationship between oxidative stress and CIN:The patients of Percutaneous coronary intervention(PCI)were divided into CIN group and non-CIN group,and collected their general data,determinated and contrasted oxidative stress and inflammatory biomarkers of serum.2.Isolation,purification and antioxidant activity of SFP:Contrasted the difference between cold water method(sargassum fusiforme polysaccharides-Cold SFP-C)and hot water method(sargassum fusiforme polysaccharides-Hot SFP-H),determinated the content of total sugar,silver radical,glucuronic acid,protein and monosaccharide in SFP,and then determinated the scavenging activity of superoxide radical.3.Evaluation on the performance of SFP in preventing CIN:The rats were divided into 4 groups as Sham group,CIN group,CIN+SFP-C group,and SFP-C group.Determinated and contrasted blood urea nitrogen(BUN)and serum creatinine(SCr),superoxide dismutase(SOD)and malondialdehyde(MDA)in renal tissue,and then observed kidney tissues injury of rats in each group by HE staining.Results:1.Oxidative stress biomarkers of CIN patient:General data P value of each group patient was greater than 0.05.The increase trend of MDA in CIN patients after PCI was higher than that in non-CIN patients,while SOD showed the opposite trend.With the increase of SCr,the expression of MDA in the serum of patients was increased,while the SOD value was decreased,and the difference was statistically significant.2.Determination of SFP composition and antioxidant activity:The SFP-C and SFP-H was 7.5%and 9.1%after cold water treatment and hot water treatment,respectively.The proportions of total sugar,silver radical,glucuronic acid and protein were 85.5%,19.3%,8.3%and 0.3%by cold water treatment.Quantitative analysis of monosaccharide components shown that trehalose occupied a large molar ratio(56.1).SFP have the ability of scavenging superoxide free radicals,and SFP-C showed higher scavenging ability of oxygen free radical,P<0.05.3.The antioxidant result of SFP in rats:Compared with CIN group,after SFP-C prevention,the expression of MDA in tissue cells was significantly decreased,while the expression of SOD was significantly increased,P<0.05.And after SFP-C prevention,the necrosis of renal tubules and infiltration of inflammatory cells in rats were significantly reduced.Conclusion:1.Oxidative stress injury is closely related to CIN.2.SFP have the ability of scavenging superoxide free radicals.3.SFP can prevent CIN in rat by inhibiting oxidative stress.The results suggested that SFP could be used in the prevention and treatment of CIN.