Effects Of Phorbol And Valproat Sodium On The Organ Toxicity In Mice Injected With Doxorubicin

ObjectiveMalignant tumors are the common factors which threat human health seriously and are also the main causes of death.Chemotherapy refers to a way of treatment with use of cytotoxic drugs to kill tumor cells,inhibiting tumor cell growth or promoting apoptosis of tumor cells.As a systemic treatment,chemotherapy is effective in the treatment of primary,metastatic and subclinical metastases.However,cytotoxic drugs also inevitably cause damage to normal cells and immune cells while killing tumor cells.Doxorubicin is a highly effective and broad-spectrum antitumor drug which exerts its efficacy by destroying DNA and oxidative stress.Doxorubicin is a recognized effective agent for the treatment of solid tumors and blood cancer,but it has a very toxic effect on the hearts,kidneys and other organs,and thus limiting its clinical application.12-O-tetradecanoylphorbol-13-acetate(TPA)is a drug that has been shown to have synergistic and attenuated effects in chemotherapy.Valproat sodium is the most commonly used antiepileptic drug in clinic and has antitumor effect.However,very few studies about the combined use of TPA and VAL have been reported.This study was designed to investigate the effects of combined use of TPA and VAL on organ toxicity induced by doxorubicin,in order to supply suitable drugs with better effect and lower toxicity in clinical tumor treatment based on this experiment and theory.MethodsMale Kunming mice were divided into control group,model group,VAL group,TPA group and combination group.Model group: DOX injection through tail vein,3 mg/kg/week,until the cumulative dose became 36 mg/kg.Body weight changes and deaths were recorded before the experiment and during the following 16 weeks after administration.Then the heart,liver,kidney and other related functional indexes were observed or detected after the cumulative doses of doxorubicin reaching 12 mg/kg,30 mg/kg,36 mg/kg along with another four weeks' free activity.The creatinine kinase MB(CK-MB),Liver function indexes,alanine aminotransferase(ALT),aspartate aminotransferase(AST),Urea nitrogen(BUN)was determined by automatic biochemical analyzer.Heart index,kidney index,spleen index and thymus index were measured.Histopathological damage was observed by HE staining.Results1 The body weight of mice in model group increased continuously in the first 4 weeks,and decreased from the 5th week,and the weight at week 16 was lower than that before administration.The body weight of mice in VAL group,TPA group and TPA + VAL group were increased in the first 4 weeks and no obvious fluctuation after the following 2 weeks.The weight of the 16 th week was higher than that before the administration,and the body weight of the three groups was not significantly different,but significantly higher than the model group.2 The mortality of the mice in the model group was 52.0%,and the mortality rates in the VAL group,TPA group and TPA + VAL group were 26.1%,36% and 20% respectively,and the mortality rate was significantly lower than that of the model group.The mean survival days of mice in TPA group,TPA group and TPA + VAL group were significantly longer than that in model group,and the average survival time of TPA + VAL group was significantly longer than that of TPA group.3 The serum CK-MB level in the model group was significantly higher than that in the control group,and the CK-MB level improved with the increasing dose of DOX.The serum CK-MB levels in VAL group,TPA group and TPA+VAL group were significantly lower than that of model group.At the dose of 30 mg/kg in DOX,the level of serum CK-MB in TPA + VAL group was significantly lower than that in VAL group.At the dose of 36 mg/kg in DOX,the level of serum CK-MB in TPA + VAL group was significantly lower than those in both VAL group and TPA group.4 The serum ALT level in the model group was significantly higher than that in the control group,and the ALT level increased with the ascending dose of DOX.At the dose of 30 mg/kg and 36 mg/kg,the serum ALT levels in the VAL group,the TPA group and the TPA + VAL group were significantly lower than those in the model group.At the dose of 36 mg/kg of DOX,the serum ALT levels in the VAL group and the TPA group were significantly lower than those in the TPA + VAL group.5 The serum AST level in the model group was significantly higher than that in the control group,and the AST level improved with the increasing dose of DOX.At the dose of 12 mg/kg and 30 mg/kg,the levels of serum AST in the VAL group and TPA group were significantly lower than those in the model group.At the dose of 36 mg/kg at DOX,the serum AST level in the TPA + VAL group was significantly lower than that in the model group.At the dose of 30 mg / kg at DOX,the serum AST level in the VAL group and TPA group was significantly lower than that in TPA + VAL group.At the dose of 12 mg/kg and 36 mg/kg,the serum AST level in the TPA group was significantly lower than that in the TPA + VAL group.6 There were no significant differences in the serum level of BUN among all groups.7 The cardiac index in the model group was significantly higher than that of the control group,and the thymus index was significantly lower than that in the control group.The cardiac index of mice in TPA group and TPA + VAL group was significantly lower than that in model group,and the thymus index was significantly higher than that in model group.The renal index of TPA + VAL group was significantly lower than that of model group.The cardiac index of TPA + VAL group was significantly higher than that of TPA group.The thymus index of TPA + VAL group was significantly higher than that of VAL group and TPA group.8 The results of HE staining showed that there were abnormal cardiomyocyte interstitial,nuclear lysis,myocardial fiber dispersion,myocardial infiltration,vacuolization,necrosis and severe steatosis in the model group;myocardial edema,loose cytoplasm,pale,vacuolar nucleus,mild steatosis in the VAL group;myocardial tissue bleeding,pale cytoplasm with unclear border,mild fatty degeneration in the TPA group;and blurred cardiomyocytes,pyknotic nuclei,focal nuclei disappear,lesser damage in the VAL+TPA group.9 Model group showed vasodilation and congestion,a large number of lymphocytes,plasma cells,tissue-like cell infiltration,inflammation,tubular protein tubular appearance,luminal luminal stained cavity,ground glass-like material accumulation;VAL group showed a small amount of tube,less damage;TPA group showed a small amount of tube type,less damage;TPA+VAL group showed more normal tissue.ConclusionsThe combined use of TPA and VAL is more effective than single drug in reducing the toxicity of doxorubicin,especially,the effect of reducing heart toxicity is the most obviousbut,and it should be noted that the efficacy of combination therapy in reducing doxorubicin hepatotoxicity is worse than that of monotherapy of treatment.