Study On The Effect Of Sodium Selenite And Seabuckthorn Seed Oil On Nephrotoxicity And Hepatoxicity Of Mercury And Exploration Of Its Mechanism

ObjectiveMercury is a venenous metal distributed widely in environment. The studies on mercuric toxicity were attached importance to it in last 1950s. The research about the effect of mercury on people'health has make progress greatly with the application of many new technologies. Although people have cognizance of the sever harm of mercury and its compound, people haven' t created the similar or higher functional substitutes for them. Mercury and its compounds still have been extensively used in medicine, agriculture and industry. Human being cant extricate himself from the harm of mercury now. Numerous clinic observations and animal experiments have confirmed the neurotoxic symptom, genital toxicity , embryo toxicity and immune toxicity of mercury , but the mechanisms of damage induced by mercury are still unclear. So this study establish mercuric chloride as the research object, to explore the effects of Sodium Selenite (SS) and Seabuckthorn Seed Oil ( SBO) on part change of enzymatic result both in liver and renal cortex induced by mercury, the effects of SS and SBO on oxida-tive damage of liver and kidney caused by mercury and the effect of SS on renal cortex cell apoptosis and part relative gene induced by mercury. Accordingly, to provide further academic evidences for the molecular biological mechanism of mercuric renal damage.Method1. The effect of Sodium Selenite and Seabuckthorn Seed Oil on part changeof enzymatic result in liver and renal cortex induced by mercuryWistar rats were divided randomly into four groups. The rats of control group were given subcutaneous injection with 0.9% saline. The rats in mercuric chloride group were subcutaneously injected with 2.5mg/kg HgCl2. The rats in SS group were pretreated with 20fimol/kg SS injecting from abdominal cavity and the rats in SBO group were pretreated with pouring 95% SBO 5ml/kg into stomach. Two hours later, the rats both SS group and SBO group were injected subcutaneously with 2. 5mg/kg HgCl2. The 12h urine samples were collected. All rats were put to death at 48h after injection, and the blood samples were collected the liver and renal cortex were removed. Mercury contents in the liver, renal cortex and urine samples were measured. Urinary NAG, ALP, LDH activities, urinary protein and serum BUN contents were also checked up.2. Experimental study of the effects of Sea Buckthorn Oil and Sodium Sele-nite on oxidative damage of liver and kidnev induced bv mercurvWistar rats were divided randomly into four groups. The rats of control group were given subcutaneous injection with 0.9% saline. The rats in mercuric chloride group were subcutaneously injected with 2.5mg/kg HgCl2. The rats in SS group were pretreated with 20jxmol/kg SS injecting from abdominal cavity and the rats in SBO group were pretreated with pouring 95% SBO 5 ml/kg into stomach. Two hours later, the rats both SS group and SBO group were injected subcutaneously with 2. 5mg/kg HgCl2 GSH, MDA, protein contents and GSH -Px, SOD activities both in the liver and renal cortex were checked up.3. The effect of Sodium Selenite on renal cortex cell apoptosis and part change of relative gene induced by mercuryWistar rats were randomly divided into five groups. The rats of control group were given subcutaneous injections with 0. 9% saline, the rats in mercuric chloride group were subcutaneous injections with 2. 5mg/kg HgCl2, the rats in SS control group were given abdominal cavity injected with 20|xmol/kg SS, the rats in SS treated group I were pretreated with 20(xmol/kg SS, two hours later injected subcutanely with 2. 5mg/kg HgCl2 the rats in SS treated group II were abdominal cavity injected with 20|xmol/kg Na2Se03 and injected subcutaneously with 2. 5mg/kg HgCl2 at the same time. All rats were put to death 48h after in-jection. Cell apoptosis of renal cortex, gene expression such as c - fos mRNA, c -jun mRNA and p38MAPK mRNA and protein expression such as FOS , JUN and JNK,p38MAPK were checked up.4. Statistic analysisAll results were expressed as mean± standard deviation and treated in SPSS12. 0 software by one - way analysis of variance (ANOVA) to test the significant differences among groups followed by q test ( Student - Newman -Keuls, SNK) to find the differences between the groups.Result1. The effect of Sodium Selenite and Seabuckthorn Seed Oil on part change of enzymatic result both in liver and renal cortex induced by mercuryThe level of mercury contents in the liver of SS pretreatment group was higher, mercury concentrations both in renal cortex and urine, Urinary NAG, ALP, LDH activities, urinary protein and serum BUN contents were lower significantly than that of mercuric chloride group ( P < 0. 05 ). Both the level of mercury contents in the liver and in renal cortex, urinary NAG, ALP, LDH activities , urinary protein and serum BUN contents of SBO pretreated group were lower significantly than that of mercuric chloride group (P <0. 05).2. Experimental study of the effects of Sea Buckthorn Oil and Sodium Selenite on oxidative damage of liver and kidney induced by mercuryThe contents of GSH, activities of SOD both in the liver and renal cortex of SBO pretreated group were higher, and the MDA contents were lower than that of mercuric chloride group. But the differences were not significantly in statistics. The contents of GSH, activities of GSH - Px and SOD in the liver of SS pretreated group were higher than that of mercuric chloride group. The differences were significantly in statistics (P <0. 05). The contents of MDA in the liver of SBO pretreated group were lower than that of mercuric chloride group. But the differences were not significantly in statistics. The contents of GSH, activities of SOD in renal cortex of SS pretreated group were higher than that of mercuric chloride group. But the differences were not significantly in statistics.Activities of GSH - Px in renal cortex of SS pretreated group were higher, the contents of MDA of in renal cortex of SS pretreated group were lower than that of mercuric chloride group. The differences were significantly in statistics (P <0. 05).3. The effect of Sodium Selenite on cell apoptosis of renal cortex and part relative gene change induced by mercury3. 1 Results of TUNNEL experimentTUNNEL positive cell were observed in rats kidney both in mercuric chloride group and in SS control group. TUNNEL positive cell were fewer in SS treated group I and II.3. 2 Results of flow cytometry analysisRates of renal cell apoptosis among mercuric chloride group, SS control group and SS treated group I were higher than that of control group. All the differences were significantly in statistics ( P <0. 05) . Rate of renal cell apoptosis among SS control group, SS treated group I and SS treated group II were lower than that of mercuric chloride group. All the differences were significantly in statistics ( P <0. 05). Rates of renal cell apoptosis both in SS treated group I and SS treated group II were lower than that of SS control group. All the differences were significantly in statistics (P<0.05).3. 3 Experimental results of RT - PCRThe expression of c -jun mRNA, c - fos mRNA and p38MAPK mRNA in renal cortex cell of mercuric chloride group, the expression of c -jun mRNA in renal cortex cell of SS control group, the expression of c - jun mRNA and c - fos mRNA in renal cortex cell of SS treated group I , the expression of c -jun mRNA in renal cortex cell of SS treated group II were all higher than that of control group. The differences were all significantly in statistics (P <0. 05). The expression of c - jun mRNA and c - fos mRNA in renal cortex cell both in SS treated group I and in SS treated group II , The expression of p38MAPK mRNA in renal cortex cell of SS treated group II were higher than that of mercuric chloride group. The differences were all significantly in statistics (P < 0. 05).3. 4 Experimental results of Western BlottingCompare with control group, the expression of phosphor - JUN protein,phosphor - JNK protein, phosphor - p38MAPK protein and the expression of FOS protein in renal cortex cell among mercuric chloride group, SS control group, SS treated group I and SS treated group II were higher significantly. The expression of phosphor - JUN protein, phosphor - JNK protein, phosphor -p38MAPK protein and the expression of FOS protein in renal cortex cell both in SS treated group I and in SS treated group II were higher than that of mercuric chloride group. All the differences were significantly in statistics (P <0. 05). Compare with SS control group, the expression of phosphor - JUN protein, phosphor - JNK protein, phosphor - p38MAPK protein and the expression of FOS protein in renal cortex cell all had no significant difference (P >0. 05).Conclusions1. The effect of Sodium Selenite and Seabuckthorn Seed Oil on part change of enzymatic results in liver and renal cortex induced by mercurySBO can promote excretion of mercury from the kidney of rats. SBO and Sodium Selenite had antagonistic effects of enzymatic change on both in liver and kidney induced by mercury.2. Experimental study of the effects of Sea Buckthorn Oil and Sodium Selenite on oxidative damage of liver and kidney induced by mercurySBO had not significantly protective effects on oxidative damage both in the liver and kidney induced by mercury. Sodium Selenite had significantly antagonistic effects on oxidative damage induced by mercury both in the liver and kidney.3. The effect of Sodium Selenite on cell apoptosis of renal cortex and part relative gene change induced by mercurySS decreased rates of cell apoptosis in renal cortex induced by mercury, and decreased the expression of relative gene such as c - fos mRNA, c - jun mRNA and p38 MAPK mRNA. SS protected renal cortex from oxidative damage caused by mercury. SS can decreased the expression of JUN protein , JNK protein , P38 MAPK protein and FOS protein in renal cortex cell induced by mercury.