Omega-3-fatty acid adds to the protective effect of flax lignan concentrate in pressure overload-induced myocardial hypertrophy in rats via modulation of oxidative stress and apoptosis.

Objective of the present investigation was to study the effect of the flax lignan concentrate (FLC) and Omega-3-fatty acid (O-3-FA) on myocardial apoptosis, left ventricular (LV) contractile dysfunction and electrocardiographic abnormalities in pressure overload-induced cardiac hypertrophy. The rats were divided into five groups such as sham, aortic stenosis (AS), AS+FLC, AS+O-3-FA and AS+FLC+O-3-FA. Cardiac hypertrophy was produced in rats by abdominal aortic constriction. The rats were treated with FLC (400mg/kg, p.o.), O-3-FA (400mg/kg, p.o.) and FLC+O-3-FA orally per day for four weeks. The LV function, myocardial apoptosis, and oxidative stress were quantified. FLC+O-3-FA treatment significantly reduced hemodynamic changes, improved LV contractile dysfunction, reduced cardiomyocyte apoptosis and cellular oxidative stress. Moreover, it significantly up-regulated the VEGF expression and decreased TNF-alpha level in serum. The histological analysis also revealed that FLC+O-3-FA treatment markedly preserved the cardiac structure and inhibited interstitial fibrosis. In conclusion, FLC+O-3-FA treatment improved LV dysfunction, inhibited cardiomyocyte apoptosis, improved myocardial angiogenesis, conserved activities of membrane-bound phosphatase enzymes and suppressed inflammation through reduced oxidative stress in an additive manner than FLC alone and O-3-FA alone treatment in pressure overload-induced cardiac hypertrophy.

L-glutamine supplementation prevents the development of experimental diabetic cardiomyopathy in streptozotocin-nicotinamide induced diabetic rats.

The objective of the present investigation was to evaluate the effect of L-glutamine on cardiac myopathy in streptozotocin-nicotinamide induced diabetic rats. Diabetes was induced in overnight fasted Sprague Dawely rats by using intraperitonial injection of streptozotocin (55 mg/kg). Nicotinamide (100 mg/kg, i.p.) was administered 20 min before administration of streptozotocin. Experimental rats were divided into Group I: non-diabetic control (distilled water; 10 ml/kg, p.o.), II: diabetic control (distilled water, 10 ml/kg, p.o.), III: L-glutamine (500 mg/kg, p.o.) and IV: L-glutamine (1000 mg/kg, p.o.). All groups were diabetic except group I. The plasma glucose level, body weight, electrocardiographic abnormalities, hemodynamic changes and left ventricular contractile function, biological markers of cardiotoxicity, antioxidant markers were determined after 4 months after STZ with nicotinamide injection. Histopathological changes of heart tissue were carried out by using H and E stain. L-glutamine treatment improved the electrocardiographic, hemodynamic changes; LV contractile function; biological markers; oxidative stress parameters and histological changes in STZ induced diabetic rats. Results from the present investigation demonstrated that L-glutamine has seemed a cardioprotective activity.

Dietary flaxseed oil and fish oil modulates expression of antioxidant and inflammatory genes with alleviation of protein glycation status and inflammation in liver of streptozotocin-nicotinamide induced diabetic rats.

Beneficial effects of dietary flaxseed oil or fish oil on streptozotocin-nicotinamide induced diabetic rats were investigated. Rats were divided into three diabetic and three non-diabetic groups and received control, flaxseed oil or fish oil diets (10%w/w). Both diets reduced blood glucose, TBARS and hepatic NO. The extent of glycation measured in terms of glycated albumin and hemoglobin was reduced significantly with both diets. Flaxseed oil diet up-regulated hepatic catalase (CAT) (activity and expression), superoxide dismutase (SOD) (activity and expression) and glutathione peroxidase (GPx) expression. Fish oil diet up-regulated hepatic CAT (activity and expression), paraoxonase-1 (PON-1) expression and down-regulated heme oxygenase-1 (HO-1) expression. Furthermore, both diets down-regulated the expression of hepatic inflammatory genes TNF-α, IL-6, MCP-1, INF-γ and NF-κB. These results were supported by histopathological observations which showed better tissue preservation in both the diets. Thus, both the diets proved to be beneficial in preventing tissue injury and alleviating diabetic insults in the livers of STZ-NIC diabetic rats.

Oral L-glutamine increases active GLP-1 (7-36) amide secretion and improves glycemic control in stretpozotocin-nicotinamide induced diabetic rats.

L-glutamine is a non-essential amino acid. It decreased blood sugar, stimulated insulin secretion in type 2 diabetic patients. The objective of the present investigation was to evaluate L-glutamine increases glucagon like peptide-1 (GLP-1) (7-36) amide secretion in streptozotocin-nicotinamide (STZ-NTM) induced diabetic Sprague Dawley rats. Molecular docking study was performed to elucidate the molecular basis for GLP-1 receptor agonistic activity. Type 2 diabetes was induced in overnight fasted Sprague Dawley rats pre-treated with nicotinamide (100 mg/kg, i.p.) followed by 20 min after administration of streptozotocin (55 mg/kg, i.p.). The rats were divided into; I - nondiabetic, II - diabetic control, III - sitagliptin (5 mg/kg, p.o.), IV - L-glutamine (250 mg/kg, p.o.), V - L-glutamine (500 mg/kg, p.o.) and VI - L-glutamine (1000 mg/kg, p.o.). The L-glutamine and sitagliptin treatment was 8 week. Plasma glucose was estimated every week. Body weight, food and water intake were recorded daily. Glycosylated haemoglobin, lipid profile, plasma and colonic active (GLP-1) (7-36) amide, mRNA expression of proglucagon GLP-1, plasma and pancreatic insulin, histology of pancreata and biomarkers of oxidative stress (superoxidase dismutase, reduced glutathione, malondialdehyde, glutathione peroxidase, glutathione S transferase) were measured after 8 week. In acute study, the rats were divided into I - glucose (2.5 g/kg, p.o.), II - sitagliptin (5 mg/kg, p.o.), III - L-glutamine (250 mg/kg, p.o.), IV - L-glutamine (500 mg/kg, p.o.) and V - L-glutamine (1000 mg/kg, p.o.). Plasma glucose, active GLP-1 (7-36) amide concentration and insulin levels were measured after glucose loading. The docking data indicated that l-glutamine bind to the GLP-1 receptor. L-glutamine decreased plasma glucose, increased plasma and pancreatic insulin, increased plasma and colonic active GLP-1 (7-36) amide secretion as well as decreased oxidative stress in streptozotocin-nicotinamide induced diabetic rats.

Cycloart-23-ene-3ß, 25-diol stimulates GLP-1 (7-36) amide secretion in streptozotocin-nicotinamide induced diabetic Sprague Dawley rats: a mechanistic approach.

In previous study, we have reported cycloart-23-ene-3ß, 25-diol is an active antidiabetic constituent isolated from stem bark of Pongamia pinnata (Linn.) Pierre. The objective of the present investigation was to evaluate cycloart-23-ene-3ß, 25-diol stimulates glucagon like peptide-1 (GLP-1) (7-36) amide secretion in streptozotocin-nicotinamide induced diabetic Sprague Dawley rats. Molecular docking studies were performed to elucidate the molecular basis for GLP-1 receptor agonistic activity. Type 2 diabetes was induced in overnight fasted Sprague Dawley rats pre-treated with nicotinamide (100mg/kg, i.p.) followed by administration of streptozotocin (55 mg/kg, i.p.) 20 min after. The rats were divided into following groups; I- non-diabetic, II- diabetic control, III- sitagliptin (5mg/kg, p.o.), IV- cycloart-23-ene-3ß, 25-diol (1mg/kg, p.o.). The cycloart-23-ene-3ß, 25-diol and sitagliptin treatment was 8 week. Plasma glucose was estimated every week (week 0 to week 8). Body weight, food and water intake were recorded daily. Glycosylated haemoglobin, lipid profile, plasma and colonic active (GLP-1) (7-36) amide, mRNA expression of proglucagnon GLP-1, plasma and pancreatic insulin, histology of pancreata as well as biomarkers of oxidative stress (superoxidase dismutase, reduced glutathione, malondialdehyde, glutathione peroxidase, glutathione S transferase) were measured after 8th week treatment. In acute study, active GLP-1 (7-36) amide release, plasma glucose and insulin were measured during oral glucose tolerance test. The docking data clearly indicated cycloart-23-ene-3ß, 25-diol bind to the GLP-1 receptor. It decreased plasma glucose level, increased plasma and pancreatic insulin level as well as increased plasma and colonic active GLP-1 (7-36) amide secretion in streptozotocin-nicotinamide induced diabetic Sprague Dawley rats.

Elucidation of molecular mechanism involved in neuroprotective effect of Coenzyme Q10 in alcohol-induced neuropathic pain.

The aim of the present investigation was to evaluate the effect of Coenzyme Q10 and its combination with vitamin E in alcohol-induced chronic neuropathic pain. Male Wistar rats were orally treated with alcohol (10 g/kg, 35% v/v, b.i.d.) for 10 weeks. Coenzyme Q10 (25, 50, and 100 mg/kg) and vitamin E (100 mg/kg) were coadministered orally for 1 h after ethanol administration for 10 weeks. Various nerve functions, biochemical, and molecular parameters were assessed. Chronic administration of ethanol for 10 weeks resulted significant development of neuropathic pain. Treatment with Coenzyme Q10 (50 and 100 mg/kg) for 10 weeks showed significant and dose dependently increased in level of nociceptive threshold, endogenous antioxidant, and Na,K-ATPase enzyme. Coenzyme Q10 (50 and 100 mg/kg) significantly restored the levels of motor nerve conduction velocity and sensory nerve conduction velocity. It also showed significant decrease in levels of endogenous calcium, oxidative-nitrosative stress, TNF-α, IL-1ß, and IL-4 level. Alteration in protein expression of polymerase gamma (pol γ) was significantly restored the Coenzyme Q10 treatment. The important finding of the study is that, Coenzyme Q10 (100 mg/kg) and α-tocopherol (100 mg/kg) combination-treated rats showed more significant prevention of behavioral, biochemical, and molecular neurotoxic effect of alcohol administration than Coenzyme Q10 or α-tocopherol alone treated group. It is evident from the finding of present investigation that plethora of mechanism including inhibition of oxido-nitrosative stress, release of pro-inflammatory cytokine, modulation of endogenous biomarker, and protection of pol γ protein expression simultaneously orchestrate to exhibits neuroprotective effect of Coenzyme Q10, vitamin E and their combination.

Beneficial effects of flaxseed oil and fish oil diet are through modulation of different hepatic genes involved in lipid metabolism in streptozotocin-nicotinamide induced diabetic rats.

Dietary omega-3 fatty acids have been demonstrated to have positive physiological effects on lipid metabolism, cardiovascular system and insulin resistance. Type-2 diabetes (T2DM) is known for perturbations in fatty acid metabolism leading to dyslipidemia. Our objective was to investigate beneficial effects of dietary flaxseed oil and fish oil in streptozotocin-nicotinamide induced diabetic rats. Thirty-six adult, male, Wistar rats were divided into six groups: three diabetic and three non-diabetic. Diabetes was induced by an injection of nicotinamide (110 mg/kg) and STZ (65 mg/kg). The animals received either control, flaxseed oil or fish oil (10 % w/w) enriched diets for 35 days. Both diets lowered serum triglycerides and very low-density lipoprotein cholesterol levels and elevated serum high-density lipoprotein cholesterol levels in diabetic rats, while serum total cholesterol and LDL-C levels remained unaffected. Both the diets increased omega-3 levels in plasma and RBCs of diabetic rats. Flaxseed oil diet significantly up-regulated the key transcription factor peroxisome proliferator-activated receptor-α (PPAR-α ) and down-regulated sterol regulatory element-binding protein-1 (SREBP-1) in diabetic rats, which would have increased ß-oxidation of fatty acids and concomitantly reduced lipogenesis respectively, thereby reducing TG levels. Fish oil diet, on the contrary lowered serum TG levels without altering PPAR-α while it showed a non-significant reduction in SREBP-1 expression in diabetic rats. Another key finding of the study is the activation of D5 and D6 desaturases in diabetic rats by flaxseed oil diet or fish oil diets, which may have resulted in an improved omega-3 status and comparable effects shown by both diets. The reduced expression of Liver-fatty acid binding protein in diabetic rats was restored by fish oil alone, while both diets showed equal effects on adipocyte fatty acid-binding protein expression. We also observed down-regulation of atherogenic cytokines tumor necrosis factor-α and interleukin-6 by both the diets. In conclusion, dietary flaxseed oil and fish oil have therapeutic potential in preventing lipid abnormalities in T2DM.

Trigonelline ameliorates diabetic hypertensive nephropathy by suppression of oxidative stress in kidney and reduction in renal cell apoptosis and fibrosis in streptozotocin induced neonatal diabetic (nSTZ) rats.

Oxidative stress and apoptotic cell death in kidney have been suggested as contributing factors in the development and complication of diabetes especially in diabetic nephropathy (DN). This study investigated the effects of trigonelline (TG) on the renal functional, morphological changes and renal apoptosis in neonatal diabetic rats, a model of non-insulin-dependent diabetes mellitus. Diabetes mellitus was induced in one day old neonatal Wistar rat pups by an intraperitoneal (i.p.) injection of streptozotocin (STZ) (50mg/kg) and monitored for 16 weeks thereafter. The diabetic rats were divided as follows: the nSTZ diabetic group, the TG (50mg/kg) treated diabetic group, and the TG (100mg/kg) treated diabetic group. The age matched nondiabetic group received an injection of citrate buffer (0.1M, pH4.5). At the end kidney samples were taken for light microscopic examinations. The levels of serum creatinine and BUN were significantly low in TG (100mg/kg) treated diabetic rats. Glomerular filtration rate was improved in TG treated rats. The activities of antioxidant enzyme and membrane bound enzyme were decreased and the levels of tumor necrotic factor (TNF-α) and hydroxyproline content were increased in renal tissues of the diabetic group. TG (100mg/kg/day) treatment for a period of 4 weeks showed significant ameliorative effects on all the biochemical parameters studied. Biochemical findings were supported by histological studies. The degenerative changes in kidney tissue and fibrosis were alleviated in the TG treated groups. These results suggested that TG might have a significant role in alleviating kidney damage in nSTZ-diabetic rats.

Evaluation of ameliorative effect of quercetin in experimental model of alcoholic neuropathy in rats.

OBJECTIVE: The objective of the present investigation was to study the neuroprotective effect of the quercetin in alcohol induced neuropathy in rats. MATERIALS AND METHODS: Male Wistar rats were administered alcohol (10 gm/kg, 35% v/v, p.o. b.i.d.) for 10 weeks. Alpha tocopherol (vitamin E) was used as a standard drug. Vitamin E (100 mg/kg) and quercetin (10, 20 and 40 mg/kg) were co-administered 1 h after ethanol administration for 10 weeks. Behavioral assessment parameters, such as motor incoordination, tactile allodynia, mechanical and thermal hyperalgesia were recorded in all groups of animals. Meanwhile, motor nerve conduction velocity was also recorded. Biochemical parameters, such as nitric oxide (NO), Na(+)-K(+)-ATPase, malondialdehyde (MDA) and myeloperoxidase (MPO) were estimated in sciatic nerve. Apoptosis index was determined with help of DNA fragmentation in sciatic nerve. RESULTS AND DISCUSSION: Chronic ethanol administration for 10 weeks resulted in significant (P < 0.001) development of neuropathic pain. Chronic treatment with quercetin (20 and 40 mg/kg) for 10 weeks significantly (P < 0.001) attenuated allodynia, hyperalgesia as well as motor coordination and impaired nerve conduction velocity along with decreased level of membrane-bound Na(+)-K(+)-ATPase. It also significantly (P < 0.001) decreased elevated levels of MDA, MPO as well as pro-inflammatory mediators, such as NO. It also decreased the extent of DNA fragmentation. This alteration was more significant in vitamin E treated rats (100 mg/kg). Quercetin is a proven antioxidant that might have decreased the oxidative stress produced by chronic alcoholism. CONCLUSION: The present investigation elucidates neuroprotective effect of quercetin in alcohol induced neuropathy through modulation of membrane-bound inorganic phosphate enzyme and inhibition of release of oxido-inflammatory mediators, such as MDA, MPO and NO.

Neuroprotective effect of naringin by modulation of endogenous biomarkers in streptozotocin induced painful diabetic neuropathy.

Diabetes mellitus is a serious debilitating epidemic affecting all social strata in developing as well as developed countries. Diabetic neuropathy is most common of secondary complications associated with diabetes mellitus and is characterized by slowing of nerve conduction velocity, elevated pain, sensory loss and nerve fiber degeneration. The aim of the present investigation was to evaluate the neuroprotective effect of naringin against streptozotocin (STZ) induced diabetic neuropathic pain in laboratory rats. Four weeks after intraperitoneal injection of STZ resulted in significant decrease in mechano-tactile allodynia, mechanical hyperalgesia, thermal hyperalgesia and motor nerve conduction velocity. Activity of endogenous antioxidant like superoxide dismutase as well as membrane bound inorganic phosphate enzyme was also found to be significantly decreased. It not only caused neural cell apoptosis but also enhanced lipid peroxide, nitrite, and inflammatory mediators' (TNF-α) level. Chronic treatment with naringin (40 and 80mg/kg) for 4 weeks significantly and dose dependently attenuated the decrease in level of nociceptive threshold, endogenous antioxidant and membrane bound inorganic phosphate enzyme. It also decreased the elevated levels of oxidative-nitrosative stress, inflammatory mediators as well as apoptosis in neural cells significantly and dose dependently. The important finding of the study is that, the naringin-insulin combination not only attenuated the diabetic condition but also reversed the neuropathic pain, whereas insulin or naringin alone only improved hyperglycemia but partially reversed the pain response in diabetic rats. Thus, naringin is a potential flavonone bearing antioxidant, antiapoptotic and disease modifying property acting via modulation of endogenous biomarker to inhibit diabetes induced neuropathic pain.

Therapeutic role of curcumin in prevention of biochemical and behavioral aberration induced by alcoholic neuropathy in laboratory animals.

Painful peripheral neuropathy induced by chronic ethanol consumption is a major medico-socioeconomical problem. The objective of present investigation was to study the effect of curcumin (20, 40 and 80mg/kg; p.o.) in alcohol-induced neuropathy in rats. Ethanol (35% v/v, 10g/kg; p.o.) was administered for 10 weeks which showed a significant decrease in thermal hyperalgesia, mechanical hyperalgesia, mechanical allodynia and nerve conduction velocity. It caused enhanced malondialdehyde, oxidative-nitrosative stress, total calcium levels, inflammatory mediators (TNF-α and IL-1ß levels) along with DNA damage. Co-administration of curcumin and α-tocopherol for 10 weeks significantly and dose-dependently improved nerve functions, biochemical as well as molecular parameters and DNA damage in sciatic nerve of ethanol treated rats. Hence, it was concluded that curcumin is of potent therapeutic value in the amelioration of alcoholic neuropathy in rats and acts by inhibition of pro-inflammatory mediators like TNF-α and IL-1ß.

Effect of hydroalcoholic extract of Hibiscus rosa sinensis Linn. leaves in experimental colitis in rats.

OBJECTIVE: To elucidate the ameliorative effect of hydroalcoholic extract of leaves of Hibiscus rosa sinensis (HRS) in acetic acid induced experimental colitis in male wistar rats. METHODS: The animals were administered with 2 mL acetic acid (4%) via intra rectal. The animals were divided into various treatment groups (n=6). Prednisolone was used as standard drug and HRS was administered at a dose of 50, 100 and 200 mg/kg p.o. The control group of animals received 1 mL of vehicle (distilled water). Ulcer area, ulcer index, spleen weight, colon weight to length ratio, macroscopic score, haematological parameters, colonic superoxide dismutase (SOD), glutathione (GSH), myeloperoxidase (MPO), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), nitric oxide (NO) and histological changes were recorded after the treatment regimen of 11 days. RESULTS: Intrarectal instillation of acetic acid caused enhanced ulcer area, ulcer index, spleen weight, colon weight to length ratio, colonic MPO, MDA, NO and TNF-α It caused significant decreased level of SOD and GSH. Pretreatment with HRS for 7 days exhibited significant effect in lowering of oxidative stress, colonic NO, TNF-α and elevation of SOD and GSH at a dose of 100 and 200 mg/kg in acetic acid induced colitis. CONCLUSIONS: The present investigation demonstrates HRS is of potent therapeutic value in the amelioration of experimental colitis in laboratory animals by inhibiting the proinflammatory mediator like NO and TNF-α.

Cardioprotective effect of whole fruit extract of pomegranate on doxorubicin-induced toxicity in rat.

CONTEXT: Cardioprotective effects of various plants are generally attributed to their antioxidant activity. The whole fruit extract of pomegranate (WFEP), Punica granatum L. (Punicaceae), has a potent antioxidant activity. OBJECTIVE: To investigate cardioprotective effect of WFEP against doxorubicin (Dox)-induced cardiotoxicity in rats. MATERIALS AND METHODS: Male Wistar rats were divided randomly into three groups of eight rats each: control (water, 5 mL/kg); Dox (10 mg/kg i.v.) and WFEP (100 mg/kg). Dox was administered in Dox and WFEP groups. After anesthetizing the animals on the last day, electrocardiogram was recorded and blood was analyzed for creatine kinase-MB isoenzyme (CK-MB), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) activities. Determinations of superoxide dismutase (SOD), reduced glutathione (GSH), lipid peroxidation (LPO) and histopathology of the heart tissues were carried out. RESULTS: The WFEP group showed decreased QT and increase in heart rate (p < 0.05) compared to the Dox group. Significant decrease in CK-MB (p < 0.01), LDH (p < 0.05) and no such significant decrease in AST were observed as compared to the Dox group. There was significant increase in the level of GSH (p < 0.05), whereas inhibition of LPO and increase in SOD concentration was not significant in the WFEP group compared to the Dox group. Histopathological study of the WFEP-treated group showed slight protection against myocardial toxicity induced by Dox. CONCLUSION: Results indicate that WFEP has cardioprotective effect against Dox-induced cardiotoxicity in rats.

Renoprotective effect of Linum usitatissimum seeds through haemodynamic changes and conservation of antioxidant enzymes in renal ischaemia-reperfusion injury in rats.

OBJECTIVE: To evaluate an ethanolic extract of seeds of Linum usitatissimum (Linn.) (EELU) for its renoprotective role in rats through its antihypertensive effect and conservation of biological oxidation enzymes. MATERIALS AND METHODS: Male Wistar rats (200-250 g) underwent uninephrectomy on day 0; after 2 weeks of recovery, the nephrectomised rats were divided into four groups of eight each: (I) sham (II); renal ischaemia reperfusion (RIR); (III) RIR + EELU 200 mg/kg; and (IV) RIR + EELU 400 mg/kg. In group II, III and IV the renal artery was occluded for 45 min and reperfused for 4 weeks; the sham group did not undergo RIR. RESULTS: EELU (400 mg/kg) significantly decreased the haemodynamic changes after 4 weeks of RIR injury. EELU treatment significantly restored the levels of renal endogenous antioxidant enzymes and membrane-bound enzymes. EELU 400 mg/kg restored the levels of blood urea nitrogen and serum creatinine. EELU also decreased the levels of tumour necrosis factor-α and myeloperoxidase activity. A flow-cytometric study confirmed a significant decrease in cellular necrosis and increase in viability after RIR in EELU-treated rats. The anti-apoptotic role of EELU was evident from the decrease in DNA fragmentation. Renal tissue damage as assessed by histopathology was decreased in groups III and IV (200 and 400 mg/kg EELU). CONCLUSION: We conclude that EELU protected the kidney against RIR-induced renal injury, probably by inhibiting reactive oxygen species that have a causal role in such cases. It also inhibits apoptotic cell death and inflammation, and improves haemodynamic changes.

Effect of pretreatment with coenzyme Q10 on isoproterenol-induced cardiotoxicity and cardiac hypertrophy in rats.

BACKGROUND: Coenzyme Q10 (CoQ10) is a lipid-soluble, vitamin-like substance found in the hydrophobic interior of the phospholipid bilayer of most cellular membranes. It appears to be involved in the coordinated regulation between oxidative stress and antioxidant capacity of heart tissue when the heart is subjected to oxidative stress in various pathogenic conditions. OBJECTIVE: The objective of the present study was to investigate the effect of pretreatment with CoQ10 (100 mg/kg) on isoproterenol (ISO)-induced cardiotoxicity and cardiac hypertrophy in rats. METHODS: Albino male Wistar rats (250-300 g) were evenly divided by lottery method into 1 of the following 3 groups: the ISO group (olive oil 2 mL/kg orally for 18 days and ISO 1 mg/kg IP from days 9-18); the CoQ10 + ISO group (CoQ10 100 mg/kg orally for 18 days and ISO 1 mg/kg IP from days 9-18); and the control group (olive oil 2 mL/kg orally for 18 days and water IP from days 9-18). Twenty-four hours after the last dose of water or ISO, the rats were anesthetized and an ECG was recorded. Blood was withdrawn by retro-orbital puncture for estimation of serum creatine kinase-MB (CK-MB) isoenzyme levels, lactate dehydrogenase (LDH) levels, and aspartate aminotransferase activities. The animals were euthanized using an overdose of ether. The hearts of 6 animals from each group were used for estimation of superoxide dismutase (SOD) activity, reduced glutathione (GSH) concentration, lipid peroxidation (LPO), malondialdehyde (MDA), and total protein concentration. Histopathology of the 2 remaining hearts in each group was carried out by a blinded technician. RESULTS: A total of 24 rats (8 in each group) were used in this study; all rats survived to study end. Compared with the control group, the ISO-treated rats had a significant change in heart to body weight ratio (P < 0.001); significant changes in the endogenous antioxidants (ie, significantly higher myocardial MDA concentration [P < 0.001]; significantly lower myocardial GSH concentration [P < 0.001] and SOD activity [P < 0.01]); and significantly higher serum activities of marker enzymes (eg, CK-MB [P < 0.001] and LDH [P < 0.001]). Compared with the ISO group, the CoQ10 + ISO group had a significant change in heart to body weight ratio (P < 0.001); significant changes in the endogenous antioxidants (ie, significantly lower MDA concentration [P < 0.05]; significantly higher myocardial GSH concentration [P < 0.001] and SOD activity [P < 0.05]); and significantly lower serum activities of marker enzymes (eg, CK-MB [P < 0.05] and LDH [P < 0.01]). CONCLUSION: Pretreatment with CoQ10 (100 mg/kg) for 18 days was associated with moderate protection against ISO-induced cardiotoxicity and cardiac hypertrophy, and with lower myocardial injury by preserving endogenous antioxidants and reducing LPO in rat heart.