garlic
Oxidative stress in streptozotocin-induced diabetic rats: effects of garlic oil and melatonin.

Anwar MM, Meki AR.

Department of Physiology, Faculty of Medicine, Assiut University, Assiut, Egypt. manwar59 hotmail.com

In the present study, oxidative stress in diabetic model and the effect of garlic oil or melatonin treatment were examined. Streptozotocin (60 mg/kg body weight, i.p.)-induced diabetic rats, showed a significant increase of plasma glucose, total lipids, triglyceride, cholesterol, lipid peroxides, nitric oxide and uric acid. Concomitantly, significant decreases in the levels of antioxidants ceruloplasmin, albumin and total thiols were found in the plasma of diabetic rats. Lipid peroxide levels were significantly increased in erythrocyte lysate and in homogenates of liver and kidney, while superoxide dismutase (SOD) activities were decreased in tissue homogenates of liver and kidney. Treatment of diabetic rats with garlic oil (10 mg/kg i.p.) or melatonin (200 microg/kg i.p.) for 15 days significantly increased plasma levels of total thiol, ceruloplasmin activities, albumin. Lipid peroxides, uric acid, blood glucose, total lipid, triglyceride and cholesterol were decreased significantly after treatment with garlic oil or melatonin. Nitric oxide levels were decreased significantly in rats treated with melatonin only. In erythrocytes lysate, glutathione S-transferase (GST) activities were increased significantly in rats treated with garlic oil or melatonin, while lipid peroxides decreased significantly and total thiol increased significantly in melatonin or garlic oil treatment, respectively. In liver homogenates of rats treated with garlic or melatonin, lipid peroxides were decreased significantly, and GST activities increased significantly, while SOD activities were increased significantly in liver and kidney after garlic or melatonin treatment. The results suggest that garlic oil or melatonin may effectively normalize the impaired antioxidants status in streptozotocin induced-diabetes. The effects of these antioxidants of both agents may be useful in delaying the complicated effects of diabetes as retinopathy, nephropathy and neuropathy due to imbalance between free radicals and antioxidant systems. Moreover, melatonin may be more powerful free radical scavenger than garlic oil.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12890544&dopt=Abstract garlic



garlic
Effect of garlic (Allium sativum linn) on serum lipoproteins and lipoprotein cholesterol levels in albino rats rendered hypercholesteremic by feeding cholesterol.

Kamanna VS, Chandrasekhara N.

The hypocholesteremic activity of garlic was tested by incorporation freeze-dried garlic powder at 0.5, 1.0, 2.0 and 3.0% levels in an atherogenic diet fed to rats. It was observed that 0.5 and 1.0% levels were not effective whereas the other 2 levels were. The group fed 2.0% garlic powder had much lower serum cholesterol level than the one fed 3%. The increased levels of low density lipoproteins (LDL) and LDL-cholesterol in rats fed the atherogenic diet were partly reversed in rats receiving a supplement of 2% garlic powder. On a cholesterol-containing diet, high density lipoprotein (HDL) and HDL-cholesterol levels were decreased. Inclusion of garlic powder in the atherogenic diet enhanced the percentage of HDL whereas no change was observed in HDL cholesterol levels. Commercial garlic pearls (equivalent to 0.15% garlic powder in the diet) produced a significant decrease in serum and liver cholesterol levels in rats fed the atherogenic diet. On the other hand, asafoetida at 1.5% level failed to reduce the serum cholesterol levels in the cholesterol-fed rats.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7121209&dopt=Abstract garlic



garlic
Effect of garlic feeding on regression of experimental atherosclerosis in rabbits.

Bordia A, Verma SK.

Thirty six rabbits were fed a cholesterol-containing diet for 3 months to produce atherosclerosis. Twelve rabbits were killed at the end of this period for baseline observations (Group I). The remaining animals were divided into two groups; Group II was fed stock diet and Group II was fed essential oil of garlic added to the stock diet. All the animals were killed at the end of 12 months. Blood lipids and fibrinolysis were monitored during the progression and regression phases. After cholesterol feeding was discontinued, serum total cholesterol and triglyceride concentration decreased gradually in both the groups. However, there was an increase in HDL levels in the garlic fed groups. Cholesterol feeding resulted in 80.9% atheromatous involvement of aortic surface in Group I. This remained almost the same (71.1%) after 9 months of stock feeding (Group II) while in the garlic fed group only 30.4% of the aortic surface had lesions. Correspondingly, the aortic lipid content of garlic fed animals was reduced by 72%, while in the control group there was no significant reduction. The data suggests that cholesterol is depleted from experimentally induces atherosclerosis by garlic administration.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7213027&dopt=Abstract garlic



garlic
The effect of fried versus raw garlic on fibrinolytic activity in man.

Chutani SK, Bordia A.

The effect of fried and raw garlic on blood fibrinolytic activity has been compared in 20 patients with ischaemic heart disease. Three blood samples were collected on the first day of the study and similarly on the 2nd and 7th days after garlic administration, either in raw or fried form. Fibrinolytic activity increased by 72% and 63% within 6 h of administration of raw or fried garlic, respectively. The elevated levels were maintained up to 12 h. In the second part of the study, raw or fried garlic was administered for 4 weeks to patients with ischaemic heart disease and fibrinolytic activity was measured at weekly intervals. It showed a sustained increase, rising to 84.8% at the end of 28th day when raw garlic was administered. Similarly, with fried garlic the rise was 72%. The study shows that: (i) both raw and fried garlic significantly enhance fibrinolytic activity (FA); (ii) garlic enhances FA within hours of administration; (iii) FA continues to rise with continued administration of garlic; (iv) frying removes the strong acrid smell of garlic, but preserves its useful effect on FA.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7225179&dopt=Abstract garlic



garlic
Comparative effect of clofibrate, garlic and onion on alimentary hyperlipemia.

Arora RC, Arora S.

The effect of clofibrate on the same subjects in similar test conditions were used as a control to verify the alleged beneficial effects from garlic and onion on alimentary hyperlipemia in normals and in cases with ischemic heart disease. The results showed that clofibrate checked the fat-induced (a) rises of serum triglyceride and plasma fibrinogen, and (b) falls of coagulation time (CT) and blood fibrinolytic activity (BFA). Only garlic had a clofibrate-like effect on CT but both garlic and onion checked the postprandial fall of BFA. Clofibrate, however, increased BFA even above the fasting level. Serum cholesterol and beta-lipoprotein were not appreciably affected by fat with or without any drug. Thus, surprisingly, the so-called beneficial effects of garlic and onion were not seen in subjects who had shown significant changes after clofibrate.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7259824&dopt=Abstract garlic