Study On Mechanism Of Male Reproductive Injury Induced By Molybdenum And The Protective Effect Of Quercetin On The Injury

The experiment was implemented to study the reproductive function damage ofhigh molybdenum on male mice and the method of injury alleviating. The epididymiscoefficients of mouse were calculated, three sperm parameters(density, vitality anddeformity rate) were detected by microscope, biochemical indexes(MDA content, SODand GSH-Px activities) of testis tissue were tested through kits, contents of4kinds traceelements(copper, zinc, iron and manganese) in blood and testis were measured,morphological changes of the testis and epididymis were observed. The purpose was todiscuss the damage effect of high molybdenum on reproductive function of male miceand its possible mechanism, and find effective drugs of alleviating reproductive functioninjury of male animal induced by molybdenum and its optimum dose.The experimentwas divided into two parts:1. Exploration of damage effects of molybdenum on the reproductive capacity ofmale mice and its possible mechanism.To obtain the minimum concentration of molybdenum induced significantreduction of reproductive ability of male mice, damage effects of differentconcentrations of molybdenum on reproductive system of male mice were studied.90healthy adult ICR mice were randomly divided into6groups. After oraladministration of distilled water containing concentration of0,12.5,25,50,100,200mg/L molybdenum freely for2weeks, epididymis coefficients of mouse were calculatedafter weighing the epididymis weights, the contents of trace elements were measured,the contents of MDA, SOD and GSH-Px activities in testis were detected, pathologicalchanges of testis and epididymis were examinated, sperm density, vitality and deformityrate were assessed. According to the results, different concentrations of molybdenumcould cause the changes of various indexes except the control group, especially whenthe concentration was100mg/L. Compared with the control, the epididymiscoefficients of mice at100mg/L Mo group decreased significantly(P<0.01); copper content decreased significantly(P<0.05), zinc and manganese contents increased, thedifference was significant or extremely significant, iron content unchanged; the spermdensity and activity decreased significantly(P<0.05), malformation rate increased(P<0.01); high molybdenum could also increase oxidative stress of testicular tissue, theMDA content increased, the activities of GSH-Px and SOD decreased, the differenceswere significant or extremely significant;100mg/L Mo could induce all levels of germcells in the seminiferous tubules scattering, the number of elongated spermatidsreduction, mitochondrias of spermatogenic cells vacuolation, cristaes of mitochondriasdisappearing, endoplasmic reticulum expansion, the epididymal epithelium cellshedding, its main cells and mitochondriasvacuolation, The cilias whose thickness wasuneven in the free surface scattering, sperm density in the lumen reduced; in addition,moderate amount of molybdenum(25mg/L) could significantly reduce the degree ofoxidative damage of testis, promote reproductive function of mice. Therefore,100mg/Lmolybdenum could be used as the dose in the study of causing obvious toxic effect onthe reproductive function of male mice.2. The remission role of quercetin on the reproductive toxicity of molybdenumThis part was in order to study the protective effect of quercetin on malereproductive parameters reduction induced by molybdenum.90healthy mature ICRmice were randomly divided into six groups, which were treated according to water＋Oil,100mg/L Mo＋Oil,100mg/L Mo＋1mg/mL Que,100mg/L Mo＋3mg/mL Que,100mg/L Mo＋6mg/mL Que,100mg/L Mo＋9mg/mL Que for2weeks, respectively.water＋Oil was as the control group,100mg/L Mo＋Oil as the poisoning group, therest were the treatment groups. The weight of body and epididymis were recorded at theend of the trial to calculate the epididymis coefficient, the vitality, density, deformityrate of the sperm were accounted, the MDA content, SOD and GSH-Px activities oftesticular tissue were detected by kits, the trace elements in blood and testis tissue weredetermined, pathological changes of the testis and epididymis were observed. The resultshowed, the treatment of6mg/mL Que could improve male mice epididymis,reproductive parameters and their morphological structure of the testis and epididymiseffectively, the therapertic effects of rest concentrations quercetin were not obvious, oreven no. SOD and GSH-Px activities of testicular increased significantly(P<0.01) aftersupplement of6mg/mL Que; different doses of quercetin could lead changes of traceelements contents in the testis, however, the contents of trace elements were in favor ofthe function of antioxidant enzymes in the testis. Conclusion: Quercetin had a mitigation role in the decline of semen quality testicular and oxidative damage of malemice caused by molybdenum, the better dose was6mg/mL.In summary, the appropriate concentration of molybdenum could improvereproductive function of male mice, high dose of molybdenum would cause testicularoxidative damaged and semen quality reduced obviously. The testicular lipidperoxidation injury reduced significantly, antioxidant capacity enhanced, themorphology and function of testis and epididymis were protected, the normalreproductive function of male mice were maintained after adding the appropriateamount of quercetin, which suggested that quercetin might be effective againstreproductive toxicity induced by molybdenum.