AIM:To investigate whether carnitine deficiency is a risk factor during the development of diethylnitrosamine (DENA)-induced hepatic carcinogenesis. METHODS:A total of 60 male Wistar albino rats were divided into six ...AIM:To investigate whether carnitine deficiency is a risk factor during the development of diethylnitrosamine (DENA)-induced hepatic carcinogenesis. METHODS:A total of 60 male Wistar albino rats were divided into six groups with 10 animals in each group.Rats in group 1(control group)received a single intraperitoneal(i.p.)injection of normal saline. Animals in group 2(carnitine-supplemented group) were given L-carnitine(200 mg/kg per day)in drinking water for 8 wk.Animals in group 3(carnitine-depleted group)were given D-carnitine(200 mg/kg per day)and mildronate(200 mg/kg per day)in drinking water for 8 wk.Rats in group 4(DENA group)were injected with a single dose of DENA(200 mg/kg,i.p.)and 2 wk later received a single dose of carbon tetrachloride(2 mL/kg) by gavage as 1:1 dilution in corn oil.Animals in group 5(DENA-carnitine depleted group)received the same treatment as group 3 and group 4.Rats in group 6 (DENA-carnitine supplemented group)received the same treatment as group 2 and group 4.RESULTS:Administration of DENA resulted in a significant increase in alanine transaminase(ALT), gamma-glutamyl transferase(G-GT),alkaline phosphatase(ALP),total bilirubin,thiobarbituric acid reactive substances(TBARS)and total nitrate/ nitrite(NOx)and a significant decrease in reduced glutathione(GSH),glutathione peroxidase(GSHPx), catalase(CAT)and total carnitine content in liver tissues.In the carnitine-depleted rat model,DENA induced a dramatic increase in serum ALT,G-GT,ALP and total bilirubin,as well as a progressive reduction in total carnitine content in liver tissues.Interestingly, L-carnitine supplementation resulted in a complete reversal of the increase in liver enzymes,TBARS and NOx,and a decrease in total carnitine,GSH,GSHPx, and CAT induced by DENA,compared with the control values.Histopathological examination of liver tissues confirmed the biochemical data,where L-carnitine prevented DENA-induced hepatic carcinogenesis while D-carnitine-mildronate aggravated DENA-induced hepatic damage. CONCLUSION:Data from this study suggest for the first time that:(1)carnitine deficiency is a risk factor and should be viewed as a mechanism in DENA- induced hepatic carcinogenesis;(2)oxidative stress plays an important role but is not the only cause of DENA-induced hepatic carcinogenesis;and(3) long-term L-carnitine supplementation prevents the development of DENA-induced liver cancer.展开更多
Introduction Carnitine plays a crucial role in energy metabolism by transporting long-chain fatty acids into mitochondria for𝛽-oxidation and removing waste metabolites.[1]Approximately 98%of the body’s total ...Introduction Carnitine plays a crucial role in energy metabolism by transporting long-chain fatty acids into mitochondria for𝛽-oxidation and removing waste metabolites.[1]Approximately 98%of the body’s total carnitine is stored in skeletal muscle,with blood serving as the transport medium.[2]Carnitine is synthesized in the liver and kidneys from lysine and methionine,but endogenous production is limited.The body preserves carnitine levels through renal reabsorption and stores in organs such as skeletal muscles,the liver,kidneys,and heart.[3]However,carnitine deficiency is prevalent in approximately 95%of hemodialysis patients due to extracorporeal loss during dialysis and impaired renal synthesis.[4]L-carnitine replacement therapy can mitigate complications,including cardiac issues,anemia,and muscle weakness.展开更多
基金Supported by Operating grant from Research Center,Collegeof Pharmacy,King Saud University(CPRC 207)
文摘AIM:To investigate whether carnitine deficiency is a risk factor during the development of diethylnitrosamine (DENA)-induced hepatic carcinogenesis. METHODS:A total of 60 male Wistar albino rats were divided into six groups with 10 animals in each group.Rats in group 1(control group)received a single intraperitoneal(i.p.)injection of normal saline. Animals in group 2(carnitine-supplemented group) were given L-carnitine(200 mg/kg per day)in drinking water for 8 wk.Animals in group 3(carnitine-depleted group)were given D-carnitine(200 mg/kg per day)and mildronate(200 mg/kg per day)in drinking water for 8 wk.Rats in group 4(DENA group)were injected with a single dose of DENA(200 mg/kg,i.p.)and 2 wk later received a single dose of carbon tetrachloride(2 mL/kg) by gavage as 1:1 dilution in corn oil.Animals in group 5(DENA-carnitine depleted group)received the same treatment as group 3 and group 4.Rats in group 6 (DENA-carnitine supplemented group)received the same treatment as group 2 and group 4.RESULTS:Administration of DENA resulted in a significant increase in alanine transaminase(ALT), gamma-glutamyl transferase(G-GT),alkaline phosphatase(ALP),total bilirubin,thiobarbituric acid reactive substances(TBARS)and total nitrate/ nitrite(NOx)and a significant decrease in reduced glutathione(GSH),glutathione peroxidase(GSHPx), catalase(CAT)and total carnitine content in liver tissues.In the carnitine-depleted rat model,DENA induced a dramatic increase in serum ALT,G-GT,ALP and total bilirubin,as well as a progressive reduction in total carnitine content in liver tissues.Interestingly, L-carnitine supplementation resulted in a complete reversal of the increase in liver enzymes,TBARS and NOx,and a decrease in total carnitine,GSH,GSHPx, and CAT induced by DENA,compared with the control values.Histopathological examination of liver tissues confirmed the biochemical data,where L-carnitine prevented DENA-induced hepatic carcinogenesis while D-carnitine-mildronate aggravated DENA-induced hepatic damage. CONCLUSION:Data from this study suggest for the first time that:(1)carnitine deficiency is a risk factor and should be viewed as a mechanism in DENA- induced hepatic carcinogenesis;(2)oxidative stress plays an important role but is not the only cause of DENA-induced hepatic carcinogenesis;and(3) long-term L-carnitine supplementation prevents the development of DENA-induced liver cancer.
文摘Introduction Carnitine plays a crucial role in energy metabolism by transporting long-chain fatty acids into mitochondria for𝛽-oxidation and removing waste metabolites.[1]Approximately 98%of the body’s total carnitine is stored in skeletal muscle,with blood serving as the transport medium.[2]Carnitine is synthesized in the liver and kidneys from lysine and methionine,but endogenous production is limited.The body preserves carnitine levels through renal reabsorption and stores in organs such as skeletal muscles,the liver,kidneys,and heart.[3]However,carnitine deficiency is prevalent in approximately 95%of hemodialysis patients due to extracorporeal loss during dialysis and impaired renal synthesis.[4]L-carnitine replacement therapy can mitigate complications,including cardiac issues,anemia,and muscle weakness.
