Cardioprotective effects of MET-88, a gamma-butyrobetaine hydroxylase inhibitor, on cardiac dysfunction induced by ischemia/reperfusion in isolated rat hearts

Inhibition of fatty acid metabolite accumulation may be beneficial for treatment of cardiac dysfunction induced by ischemia. MET-88, 3-(2,2,2-trimethylhydrazinium)propionate dihydrate, inhibits gamma-butyrobetaine hydroxylase which catalyzes conversion of gamma-butyrobetaine to carnitine. In this study, we investigated whether MET-88 has cardioprotective effects against cardiac dysfunction induced by ischemia/reperfusion. Rats were divided into four groups: (1) control; (2) MET-88 at 50 mg/kg; (3) MET-88 at 100 mg/kg; (4) nifedipine at 30 mg/kg. MET-88 was administered orally once a day for 10 days, and nifedipine was administered orally 30 min before the experiments. Cardiac functions (heart rate, left ventricular systolic pressure and coronary flow) were measured in rat working heart preparations for 30 min under ischemia followed by 20 min under reperfusion. Myocardial carnitine levels were measured at the end of the experiments. Before ischemia, MET-88 did not affect cardiac functions, but nifedipine significantly increased only coronary flow. Under the ischemic condition, cardiac functions were markedly decreased in all groups. During reperfusion, MET-88 and nifedipine promoted recovery of cardiac functions and decreased the incidence of ventricular fibrillation. MET-88 also prevented the accumulation of long-chain acylcarnitine induced by ischemia. These results indicated that MET-88 protected against cardiac dysfunction in ischemia/reperfusion, and preventing the accumulation of long-chain acylcarnitine may be responsible for the cardioprotective effects.     

Pharmacokinetics and biological fate of 3-(2,2, 2-trimethylhydrazinium)propionate dihydrate (MET-88), a novel cardioprotective agent, in rats.

In this study, we examined the disposition, metabolism, and excretion of a novel cardioprotective agent, 3-(2,2, 2-trimethylhydrazinium)propionate dihydrate (MET-88), in rats. The disposition of MET-88 after oral and i.v. administration of 2, 20, and 60 mg/kg indicated that the pharmacokinetics of MET-88 were nonlinear. The profiles of radioactive MET-88 and total radioactivity in plasma were consistent at doses of 20 and 60 mg/kg. However, at 2 mg/kg, the plasma MET-88 levels were obviously lower than the total. The excretion of radioactivity after oral administration of MET-88 indicated that increasing doses led to a shift from exhaled CO(2) to urinary excretion as the major excretion route. Major metabolites in plasma after oral administration of MET-88 were glucose, succinic acid, and 3-hydroxypropionic acid, and in vitro studies revealed that MET-88 was converted to 3-hydroxypropionic acid by gamma-butyrobetaine hydroxylase (EC 1.14. 11.1). An isolated liver perfusion system modified to trap CO(2) gas was used to examine the excretion pathway of MET-88. [(14)C]CO(2) gas was decreased by the addition of iodoacetic acid, DL-fluorocitric acid, or gamma-butyrobetaine to this system, and subsequent thin-layer chromatography analyses of perfusates revealed that MET-88 was first converted to 3-hydroxypropionic acid by gamma-butyrobetaine hydroxylase and then was biosynthesized to glucose and metabolized to CO(2) gas via the glycolytic pathway and tricarboxylic acid cycle.     

Beneficial effects of MET-88, a gamma-butyrobetaine hydroxylase inhibitor in rats with heart failure following myocardial infarction

Myocardial ischemia can cause myocardial infarction and as a consequence, heart failure. 3-(2,2,2-trimethylhydrazinium) propionate (MET-88) inhibits gamma-butyrobetaine hydroxylase and has cardioprotective effects on the ischemic heart. We now examined the effects of MET-88 in rats with congestive heart failure following myocardial infarction. Congestive heart failure was produced by left coronary artery ligation in rats. MET-88 at 100 mg/kg/day was orally administered from the 2nd day after surgery. We performed a survival study for 181 days, and measured ventricular remodeling, cardiac function, and myocardial high-energy phosphate levels after treatment for 20 days. MET-88 prolonged survival with a median 50% survival of 103 days compared to 79 days for the heart-failure control rats. The expansion of the left ventricular cavity (ventricular remodeling) in heart-failure rats was prevented by treatment with MET-88, and the effect of MET-88 was similar to that of captopril at 20 mg/kg. MET-88 attenuated the rise in right atrial pressure in heart-failure rats and augmented cardiac functional adaptability against an increased load. Also, MET-88 improved the myocardial energy state in heart-failure rats. The present results indicate that MET-88 improves the pathosis in rats with heart failure induced by myocardial infarction.     

Carnitine deficiency provokes cisplatin-induced hepatotoxicity in rats

This study investigates whether or not carnitine deficiency is a risk factor and could contribute to cisplatin-induced liver toxicity. A total of 60 adult male Wistar albino rats were divided into six groups. The first three groups were injected intraperitoneally with normal saline, propionyl-l-carnitine (500 mg/kg), and d-carnitine (500 mg/kg), respectively, for 10 successive days. The fourth, fifth and sixth groups were injected intraperitoneally with the same doses of normal saline, propionyl-l-carnitine and d-carnitine, respectively, for 5 successive days before and after a single dose of cisplatin (7 mg/kg). Administration of the standard nephrotoxic dose of cisplatin did not produce any changes in serum alanine transaminase and gamma-glutamyl transferase and no morphological changes in liver tissues. However, it did produce a significant increase in thiobarbituric acid reactive substances and total nitrate/nitrite and a significant decrease in reduced glutathione content in liver tissues. On the other hand, combined treatment with cisplatin and d-carnitine induced a dramatic increase in serum alanine transaminase and gamma-glutamyl transferase, as well as progressive reduction in total carnitine and ATP content in liver tissue. Moreover, histopathological examination of liver tissues confirmed the biochemical data, where cisplatin and d-carnitine combination showed signs of liver injury manifested as focal necro-inflammatory changes and portal inflammation. Interestingly, in carnitine supplemented rats using propionyl-l-carnitine, cisplatin did not produce any biochemical and histopathological changes in liver tissues. In conclusion, data from this study suggest for the first time that (1) carnitine deficiency is a risk factor and could precipitate cisplatin-induced hepatotoxicity, (2) oxidative stress is not the main cause of cisplatin-related hepatotoxicity and (3) propionyl-l-carnitine prevents the development of cisplatin-induced liver injury.     

PROTECTIVE EFFECTS OF MANGANESE AGAINST LIPID PEROXIDATION

The aim of this study was to investigate the effects of chronic, daily, 30-d administration of manganese chloride (MnCl₂) to male Sprague-Dawley rats on lipid peroxidation in various tissues. Rats were intraperitoneally injected with MnCl₂ (20 mg/kg) once daily for 30 con secutive days. The Mn accumulated in liver, spleen, adrenal glands, heart, kidneys, lung, and testes. This was associated with decreased lipid peroxidation in liver, spleen, and adrenal glands and a decrease in the levels of Fe in these tissues. In a second group of animals, Mn (20 mg/kg/d) and glutathione (GSH, 15 mg/kg/d) were administered ip for 30 d. GSH counteracted the Mn-induced protective fall in lipid peroxidation, but Fe levels remained lower in liver and spleen. Mn decreases lipid peroxidation in certain tissues, which may involve lowering Fe content, but interaction with Fe is not the sole mechanism.     

Differential effects of GABA transaminase inhibitors on sexual behavior, locomotor activity, and motor execution in the male rat

The GABA transaminase inhibitors gamma-acetylen GABA (GAG) and sodium valproate were administered intraperitoneally and their effects on locomotor activity, motor execution and sexual behavior were analyzed. It was found that sodium valproate, administered 15 min before observation, reduced locomotor activity only at a dose of 200 mg/kg. Doses of 100 and 400 mg/kg had no effect. Motor execution was impaired in a dose-dependent way, the lowest effective dose being 200 mg/kg. Sexual behavior was also dose-dependently reduced. Sodium valproate, administered 60 min before observation, inhibited all behaviors. The lowest effective dose was 200 mg/kg for locomotor activity and 400 mg/kg for motor execution and sexual behavior. GAG also inhibited all behavior, in doses ranging from 25 mg/kg (locomotor activity) to 100 mg/kg (motor execution and sexual behavior). The data showed that there is no relation between effects on locomotor activity and the effects on sexual behavior, whereas sexual behavior is inhibited whenever motor execution is impaired. Moreover, there is no correlation between effects on locomotor activity and motor execution. It is suggested that GABA transaminase inhibitors effect sexual behavior only indirectly, via an impairment of motor execution. Therefore it is doubtful whether GABAergic mechanisms play any role in the normal regulation of sexual behavior.     

Effect of hydrazine on urea cycle enzymes in vitro and in vivo

The effect of hydrazine on urea cycle enzymes was studied in adult male rats. Addition of different concentrations of hydrazine to homogenates of rat liver produced a gradual inhibition of citrulline and urea synthesis. A daily injection of subconvulsive doses (32 mg/kg) of this toxic substance for 4 days provoked an increase of citrulline and urea contents in different tissues. The activities of urea cycle enzymes were not affected by such a treatment except for argininosuccinase where an increase was noted. The activity of ornithine-ketoacid transaminase was greatly inhibited. The results suggest that the inhibition of ornithine-ketoacid transaminase provokes an accumulation of ornithine. The presence of a high concentration of this amino acid together with an increased ammonia production stimulates urea synthesis. Under these physiological conditions, the condensation reaction of citrulline with aspartic acid may become ratelimiting in the operation of the urea cycle with the resultant accumulation of citrulline.     

Protective effects of manganese against lipid peroxidation

The aim of this study was to investigate the effects of chronic, daily, 30-d administration of manganese chloride (MnCl2) to male Sprague-Dawley rats on lipid peroxidation in various tissues. Rats were intraperitoneally injected with MnCl2 (20 mg/kg) once daily for 30 consecutive days. The Mn accumulated in liver, spleen, adrenal glands, heart, kidneys, lung, and testes. This was associated with decreased lipid peroxidation in liver, spleen, and adrenal glands and a decrease in the levels of Fe in these tissues. In a second group of animals, Mn (20 mg/kg/d) and glutathione (GSH, 15 mg/kg/d) were administered ip for 30 d. GSH counteracted the Mn-induced protective fall in lipid peroxidation, but Fe levels remained lower in liver and spleen. Mn decreases lipid peroxidation in certain tissues, which may involve lowering Fe content, but interaction with Fe is not the sole mechanism.     

Mildronate, an inhibitor of carnitine biosynthesis, induces an increase in gamma-butyrobetaine contents and cardioprotection in isolated rat heart infarction

The inhibition of gamma-butyrobetaine (GBB) hydroxylase, a key enzyme in the biosynthesis of carnitine, contributes to lay ground for the cardioprotective mechanism of action of mildronate. By inhibiting the biosynthesis of carnitine, mildronate is supposed to induce the accumulation of GBB, a substrate of GBB hydroxylase. This study describes the changes in content of carnitine and GBB in rat plasma and heart tissues during long-term (28 days) treatment of mildronate [i.p. (intraperitoneal) 100 mg/kg/daily]. Obtained data show that in concert with a decrease in carnitine concentration, the administration of mildronate caused a significant increase in GBB concentration. We detected about a 5-fold increase in GBB contents in the plasma and brain and a 7-fold increase in the heart. In addition, we tested the cardioprotective effect of mildronate in isolated rat heart infarction model after 3, 7, and 14 days of administration. We found a statistically significant decrease in necrotic area of infarcted rat hearts after 14 days of treatment with mildronate. The cardioprotective effect of mildronate correlated with an increase in GBB contents. In conclusion, our study, for the first time, provides experimental evidence that the long-term administration of mildronate not only decreases free carnitine concentration, but also causes a significant increase in GBB concentration, which correlates with the cardioprotection of mildronate.     

The protective effect of (4R)-hexahydro-7, 7-dimethyl-6-oxo-1, 2, 5-dithiazocine-4-carboxylic acid (SA3443), a novel cyclic disulfide, on acetaminophen-induced liver injury

Effects of (4R)-hexahydro-7, 7-dimethyl-6-oxo-1, 2, 5-dithiazocine-4-carboxylic acid (SA3443) on acetaminophen-induced liver injury were investigated in BALB/c mice. SA3443 (30-300 mg/kg, p.o.) dose-dependently suppressed the elevation of serum transaminase activities and the histological changes of liver induced by acetaminophen (150 mg/kg, p.o.). The compound at the same doses also reduced the mortality due to the lethal acute hepatic failure induced by acetaminophen (350 mg/kg, p.o.). Other hepatoprotective agents, cianidanol (500 mg/kg, p.o.), malotilate (100 mg/kg, p.o.), grycyrrhizine (10 mg/kg, i.p.) and cysteine (300 mg/kg, p.o.) similarly reduced it. SA3443 had no effect on glutathione (GSH) contents in the liver of normal mice, but it dose-dependently suppressed the decrease of GSH contents in the liver of BALB/c mice treated with acetaminophen. These results suggest that SA3443, a novel cyclic disulfide, provides considerable protection against acetaminophen-induced liver injury and that one of the modes of the hepatoprotective action of this compound is suppression of the decrease of GSH contents in the liver.     

Effect of the joint administration of ketamine and propofol on the lipid metabolism and peroxidation in rats

Ketamine (50 mg/kg, i.p.) increases the intensity of lipolysis and lipid peroxidation (LPO) in the hepatic and cardiac tissues of Wistar male rats, as manifested by an increase in the content of nonetherified fatty acids and cholesterol in the blood serum and in the content of LPO products in the blood serum and in the liver and heart tissues. Propofol in the same dose also influences the lipid metabolism and LPO intensity, but to a lower extent. The joint administration of both ketamine (25 mg/kg, i.p.) and propofol (25 mg/kg, i.p.) leads to averaging of some characteristics of the lipid metabolism and LPO.     

Sub-chronic effects of styrene and styrene oxide on lipid peroxidation and the metabolism of glutathione in rat liver and brain

Sub-chronic effects of styrene and styrene oxide on lipid peroxidation, glutathione contents and glutathione reductase activities in the liver and brain were examined after intraperitoneal administration to rats 3 times a week for 7 weeks. Styrene (300, 400 and 500 mg/kg) and styrene oxide (200 and 300 mg/kg) increased lipid peroxidation in the liver after 7 weeks of treatment. Hepatic lipid peroxidation in the rats treated with a higher dose of styrene oxide (400 mg/kg) was significantly enhanced even after 2 weeks of treatment. On the other hand, no change in lipid peroxidation was observed in the brain under the above conditions. Neither glutathione contents nor glutathione reductase activities in the liver and brain were altered at 40 h after the last of these sub-chronic treatments. To elucidate the cause of lipid peroxidation, the time courses of glutathione content after treatment with either styrene or styrene oxide (300 mg/kg) were studied in more detail. Significant decreases in both the GSH and GSSG contents were detected shortly after these treatments and the levels recovered to the control values at 40 h in these organs, although the changes were less significant in the brain of rats treated with styrene. These results suggest that enhancement of lipid peroxidation in the liver after treatment with styrene or styrene oxide was a consequence of repeated depletions of glutathione to certain critical levels and delayed recovery of lipid peroxides.     

Effects of Long‐Term Mildronate Treatment on Cardiac and Liver Functions in Rats

Abstract: Mildronate is a cardioprotective drug that improves cardiac function during ischaemia and functions by lowering l ‐carnitine concentration in body tissues and modulating myocardial energy metabolism. The aim of the present study was to characterise cardiovascular function and liver condition after long‐term mildronate treatment in rats. In addition, changes in the plasma lipid profile, along with changes in the concentration of mildronate, l ‐carnitine and γ‐butyrobetaine were monitored in the rat tissues. Wistar rats were perorally treated daily with a mildronate dose of either 100, 200 or 400 mg/kg for 4, 8 or 12 weeks. The l ‐carnitine‐lowering effect of mildronate was dose‐dependent. However, the carnitine levels reached a plateau after about four weeks of treatment. During the additional weeks of treatment, the carnitine levels were not considerably changed. The obtained results provide evidence that even a high dose of mildronate does not alter cardiovascular parameters and the function of isolated rat hearts. Furthermore, the histological evaluation of liver tissue cryosections and measurement of biochemical markers of hepatic toxicity showed that all the measured values were within the normal reference range. Our results provide evidence that long‐term mildronate administration induces significant changes in carnitine homeostasis, but it is not associated with cardiac impairment or disturbances in liver function.     

Biochemical and pathological changes in the heart and liver of rats given brominated cottonseed oil

Groups of young male rats were given daily po doses of brominated cottonseed oil (BCO) for 3 days. Control animals were given corn or cottonseed oil. The heart and liver were then removed and homogenized, and the ability of the homogenates to metabolize pyruvate and palmitate was studied. The capacity of the heart and liver of rats given 400 or 1000 mg BCO/kg for 3 days to metabolize pyruvate was similar to controls. The liver but not the heart of rats given 2500 mg/kg for 3 days had a reduced capacity to decarboxylate pyruvate. The heart but not the liver of rats given 400–2500 mg/kg showed a dose-dependent reduction in palmitate utilization. The reduction in palmitate utilization was accompanied by a morphologically apparent accumulation of lipid in the heart muscle. Additional studies indicated that the reduction in cardiac palmitate utilization could be overcome by the addition of ATP, dl-carnitine, and CoA to the medium.     

Combined effects of vitamin C, vitamin E, and sodium selenate supplementation on absolute ethanol-induced injury in various organs of rats

In this study, the effect of combination of vitamin C (ascorbic acid), vitamin E (alpha -tocopherol), and selenium (sodium selenate) on ethanol-induced liver and intestine injury in rats was investigated. The ethanol-induced injury was produced by the administration of 1 ml of absolute ethanol to each rats. Animals received vitamin C (250 mg/kg), vitamin E (250 mg/kg), and sodium selenate (Se) (0.5 mg/kg) for 3 days; 1 h after the final antioxidant administration, they were sacrificed. Lipid peroxidation and glutathione levels, catalase (CAT), lactate dehydrogenase (LDH), superoxide dismutase (SOD), and glutathione peroxidase (GP(x)) activities were determined in liver and intestine tissues. Myeloperoxidase (MPO), aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), gamma-glutamyltransferase (GGT) were determined in liver tissue. Also, CAT activity, urea, creatinine, uric acid, and total lipid levels were determined in serum samples. In the ethanol group, serum urea, creatinine, uric acid, and total lipid levels; liver and intestine LDH; liver MPO, AST, ALP, ALT, and GGT activities; and liver and intestine LPO levels increased, whereas serum CAT activity, liver and intestine GSH levels, and CAT, SOD, and GP(x) activities decreased. On the other hand, treatment with vitamin C, vitamin E, and Se reversed these effects. As a result of these findings, we can say that the combination of vitamin C, vitamin E, and selenium has a protective effect on ethanol-induced changes in lipid peroxidation, glutathione levels, and antioxidant enzyme activities in liver and intestine tissues, and in some serum parameters of rats.     

Postmortem distribution of sildenafil in histological material

This study reports results of the detection and quantitation of sildenafil (Viagra) in biological fluids and tissues and its stability in fixed tissues and formalin solutions in which the tissues were fixed. Toxicological analyses were performed on samples from a 60-year-old man who died of acute heart failure due to myocardiosclerosis. Sildenafil pills were found in his pocket. At the time of autopsy, sildenafil was found in body fluids and tissues (blood 0.04 mg/L, bile 0.99 mg/L, gastric contents 6.84 mg/L, urine 9.60 mg/L, brain 6.43 mg/kg, heart 6.10 mg/kg, kidney 4.28 mg/kg, liver 5.46 mg/kg, lung 5.38 mg/kg, spleen 1.38 mg/kg). Tissue samples were preserved in formalin solutions for four weeks. Analyses of formalin-fixed tissues and formalin solutions in which the same tissues had been preserved allowed the detection and quantitation of sildenafil (brain 2.20 mg/kg, formalin from brain 4.01 mg/L; heart 1.46 mg/kg, formalin from heart 4.41 mg/L; kidney 0.98 mg/kg, formalin from kidney 3.19 mg/L; liver 2.19 mg/kg, formalin from liver 3.21 mg/L; lung 1.02 mg/kg, formalin from lung 4.18 mg/L; spleen 0.28 mg/kg, formalin from spleen 0.94 mg/L). Results indicate that sildenafil has good stability in biological specimens subjected to chemical fixation.     

人参茎叶皂甙对家兔慢性高脂血症的脂质调节及抗过氧化脂质作用

用家兔制作高脂血症模型,将32只家兔平均分为4组;正常饲料对照组,高脂饲料对照组,30mg/kg人参茎叶皂甙(GSL)高脂饲料组,60mg/kgGSL高脂饲料组。在实验第24天去掉高脂饲料给普通正常饲料,第42天实验结束。结果表明:GSL能降低血清脂质含量,降低总胆固醇与低密度脂蛋白胆固醇的比值,高剂量的GSL能升高血清高密度脂蛋白胆固醇的含量。GSL还能降低动脉壁脂质含量及心、肝组织内总胆固醇水平,也能降低血清及以上各组织内丙二醛含量。     

Evaluation of the effects of subchronic oral administration of n-butyl maleate in Sprague-Dawley rats

n-Butyl maleate, also referred to as monobutyl maleate, is an ester of maleic acid, which is used as a counterion in the pharmaceutical industry. While substantial published data exist on short-term treatment, maleic acid-induced renal toxicity in the rat, no toxicity data are available on the monobutyl ester. This study evaluated the oral subchronic nephrotoxicity potential of n-butyl maleate administered to Sprague-Dawley rats (10/males and females/group) at doses of 0 (vehicle control), 10, 30, or 60 mg/kg/d for 2 wk. Statistically significant elevations in organ weights were noted in males at 60 mg/kg/d and included: (a) increases in absolute heart, kidney, and liver weights; (b) increased liver to body weight ratios; and (c) increased heart, kidney, liver, spleen, and epididymides to brain weight ratios. In females, statistically significant increases in organ weights were limited to increases in adrenal to brain weights at > or = 10 mg/kg/d, kidney to brain weights at > or = 30 mg/kg/d, and kidney to body weight and liver to brain weight ratios at 60 mg/kg/d. There were no macroscopic or microscopic pathology changes observed in any of the tissues examined. Importantly, light microscopic examination of the kidney was unremarkable at the end of the 2-wk dosing period with n-butyl maleate. Although lacking a histopathological correlate, resultant increases in organ weights at 60 mg/kg/d might be considered indicative of an adverse effect. However, renal perturbation induced by n-butyl maleate was mild in comparison to maleic acid-induced renal toxicity, which manifested as impaired tubular resorption and necrosis of the proximal tubules at doses > or = 60 mg/kg/d. The no-observed-adverse-effect level (NOAEL) for the study was 30 mg/kg/d.     

The mechamism of L-arginine protective influence on the liver under ischemia - reperfusion conditions

Previous investigations indicated a protective effect of L-arginine (300 mg/kg) against hepatic reperfusion injury. This was an investigation of the mechanism of this protective effect. The infusion of L-arginine under the conditions of inhibited NO synthesis (L-NAME, 10 mg/kg) significantly increased lipid peroxidation processes and transaminase activity and decreased antioxidant defense in postischemic liver. It is concluded that protective mechanism of L-arginine against hepatic reperfusion injury is associated with NO synthesis.     

枸杞多肽对D-半乳糖诱导小鼠的抗衰老作用及其可能机制

目的研究枸杞多肽对D-半乳糖（D-gal）衰老模型小鼠的影响及其可能作用机制。方法ICR小鼠60只,随机分为正常对照组、衰老模型组、枸杞多肽200,400,800mg/（kg.d）剂量组和100mg/（kg.d）维生素E（VitE）组。除正常组外均采用D-gal10mg/kg颈背部皮下注射,每日1次,连续注射5周,同时枸杞多肽和VitE组按20ml/（kg.d）灌胃给药。观察各组小鼠的行为学及学习记忆改变,并于5周后检测小鼠血清、心脏、肝脏、脑组织中超氧化物歧化酶（SOD）活性、丙二醛（MDA）含量及端粒酶活性。结果与正常对照组相比,衰老模型组小鼠体重增加明显减少,小鼠跳台错误次数明显增多,小鼠血清、心脏、肝脏和脑SOD和端粒酶活性降低,MDA含量增加（P〈0.01）。与模型组相比,枸杞多肽组和VitE组小鼠体重增加升高（P〈0.01）,小鼠跳台错误次数减少（P〈0.05）,小鼠血清、心脏、肝脏和脑组织SOD活性升高,MDA含量减少（P〈0.05）;枸杞多肽200mg/（kg.d）剂量组及VitE组小鼠血清端粒酶活性有升高的趋势,但差异不显著;400和800mg/（kg.d）剂量组小鼠血清和心脏端粒酶活性升高（P〈0.01）,VitE组小鼠心脏端粒酶活性也明显升高;而各治疗组小鼠肝脏和脑组织端粒酶活性无明显变化。结论枸杞多肽对D-gal诱导衰老模型小鼠有抗衰老作用,其机制可能与提高小鼠血清、心脏、肝脏和脑组织SOD活性,减少MDA含量,以及提高血清和心脏端粒酶活性有关。