Prophylactic Effects of Garlic Oil and Onion Oil Fractions as Compared to Vitamin E on Rats Orally Fed with Lead Acetate Solution.

Heavy metal pollution is a global public health challenge due to its stable and persistent environmental contamination. Of these lead is considered to be one of the most common ubiquitous and industrial pollutants and at low concentration it exerts extensive damages to the tissues. Daily feeding of lead acetate solution (Dose: 10 mg/kg/day) to normal rats for a month adversely altered the parameters of blood, serum and tissues, viz; RBC, WBC, Hb, ɗ- ALAD (Delta amino levulinic acid dehydratase), Pb content, lipids, oxidized lipids (TBARS), vitamins C and E and GSH levels and activities of AST, ALT and antioxidant enzymes viz; catalase, GR, Gpx and SOD. In order to study whether antioxidants have any effect to counteract the toxicity of lead we have selected comparatively better active allium fractions for the study viz: polar fraction of garlic (PFG) and polar fraction of onion (PFO). On feeding of these active fractions of garlic and onion oils i.e. their polar fractions and vitamin E (Dose 100 mg/kg/day) separately for a month along with or without lead acetate to rats each nutraceutical and vitamin E counteracted the adverse effects of Pb significantly (p ≤ 0.05). Their effects are in the order of PFG > PFO > Vitamin E. All these results point out that garlic and onion oils contain natural disulfoxide compounds which act as antioxidant and anti toxic to lead compounds. Their comparative differences in action may be due to the presence and position of double bonds and disulfide oxide bonds in their molecules. i.e., in PFG the allyl disulfide oxide group is present and in PFO saturated methyl and propyl groups and unsaturated propenyl group are present in place of allyl groups. The former group confers a better antioxidant activity on PFG, while the latter groups confer a lesser activity on PFO.

A review on the role of nutraceuticals as simple as se(2+) to complex organic molecules such as glycyrrhizin that prevent as well as cure diseases.

Nutraceuticals are nutritional medicines which are present in edible food items. Most of them are antioxidants with various other biological properties viz, anti inflammatory, anti atherogenic, anticancer, anti viral, anti aging properties etc. They are as simple as minerals like Se(2+) to complex organic molecules such as glycyrrhizin (Ca(2+), K(+) salts of glycyrrhizic acid). They can prevent as well as cure various diseases. Most of the medical people are not aware of the importance of the nutraceuticals as such matters are not part of their text books. Many still think that vitamins are the major nutritional medicines. Actually other dietary principles like terpenes, carotenes, phytosterols, polyphenols, flavanoids, di and poly sulphides, their sulfoxides and their precursor amino acids are necessary to scavenge free radicals in the body which are reactive oxygen species to protect and maintain the vitamin levels in the body. They down regulate the activities of those enzymes which are increased in diseases and they increase those that remove oxidants and detoxify carcinogens. They are immune boosters too. Recently glucosinolates, non toxic alkaloids, certain proteins and even fiber are included in the list of nutraceuticals.

Antioxidant status and oxidative stress in the circulation of younger and elderly human subjects.

Extensive research has demonstrated the protective properties of antioxidants, which scavenge reactive oxygen species and their precursors, as well as up-regulate enzymes involved in the repair of cellular damage. Several case-control studies have showed higher blood levels of antioxidants and decreased oxidative stress in younger individuals when compared with older ones. Cell damage caused by free radicals appears to be a major contributor in aging and degenerative diseases of aging such as cancer, cardiovascular disease, cataracts, compromised immune system, rheumatoid arthritis and brain dysfunction. The objective of this study was to determine the variation of Circulating levels of selected antioxidants (enzymic and non enzymic) and oxidative stress marker in younger and older humans. The results showed that a majority of the younger age group participants showed a significant increase in enzymic and nonenzymic antioxidant status and a decrease in oxidative stress when compared with the older age group.

A rethinking on the benefits and drawbacks of common antioxidants and a proposal to look for the antioxidants in allium products as ideal agents: a review.

This review article on the beneficial uses of Allium antioxidants tries to give some answers to the recent doubts raised by Singh et al. (Ind J Clin Biochem 25(3):225-243, 2010) against the claim of some researchers that Antioxidants (AOs) are miraculous molecules. Many people still believe that vitamins like A, C and E are the only true AOs that play important role in the corrections of metabolic derangements in life style diseases and hence all their faults are attributed to the failures of AOs as a class. This is quite unfair as there are many other natural AOs that do equal or even better AO action than the vitamins. Such is the case with the Allium S-alkyl sulfoxide aminoacids and their breakdown products viz, the various poly sulfides and their oxides e.g. allicin and ajoene type compounds which trap electrons mainly. It is true that antioxidant vitamins and ß-carotene a precursor of Vitamin A bring about problems as prooxidant or as agents that block some metabolic pathways and gene expression. Again the argument that AOs cannot improve the level of antioxidant enzymes like SOD, catalase and glutathione Px is also not universal. Actually allium AOs can even spare the use of antioxidant vitamins in the body and enhance the action of antioxidant enzymes and supply of ATP and other nutrients to the tissues as the former are good vasodialators and promoters of membrane permeability. The use of AOs should be selective and moderate. Allium AOs satisfy the role of ideal AOs based on many of their invivo and invitro actions reported by the author and others. Their metabolits can regenerate them and recycle them for a sufficient time in the body. They have non antioxidant effects also such as antiplatelet, fibrinolytic, antiinflammatory, immunomodulatory, antiageing actions etc. Plant derived AOs may be more beneficial and better tolerated in their partially purified forms rather than in their absolutely purified forms as the accompanying principles have some protective and regulatory effects in general. This and other aspects of allium AOs are discussed in the paper.

Garlic Oil and Vitamin E Prevent the Adverse Effects of Lead Acetate and Ethanol Separately as well as in Combination in the Drinking Water of Rats.

Daily feeding of drinking water containing lead acetate (160 mg/l) or 10% alcohol by volume or a combination of both to rats for a month produced certain deleterious effects through oxidative stress. Both heavy metal lead and alcohol are capable of doing such damages. The deleterious alterations observed were in the parameters of blood, serum and tissues, viz; Hb, Pb, proteins, lipids, lipid per oxidation, Vitamins C and E levels and enzyme activities of AST, ALT, and catalase. Simultaneous feeding of either of the two antioxidants garlic oil (GO) and vitamin E at equal doses of 100 mg/kg/day, to the rats counteracted the deleterious effects of the above two chemicals significantly. The maximum damage was brought about by feeding of drinking water containing both lead acetate and alcohol. The protective effects of GO and Vitamin E were not significantly different. The mechanism of actions of the Vitamin E and GO is probably due to their efficiency as detoxifying agents and antioxidants, to scavenging free radicals as well as an independent action of GO on the removal of lead salt as lead sulfide.

Antiatherogenic and antiperoxidative effects of garlic and soy proteins in alcohol fed rats.

Rats fed with alcohol (18%) at 3.76 g/day for 45 days showed significant reduction in body weight, glutathione (GSH) content and activities of superoxide dismutase (SOD) and catalase in liver. Lecithin cholesterol acyltransferase (LCAT) in plasma, levels of HDL cholesterol in serum, hepatic bile acid production and fecal excretion of neutral sterols also showed significant reduction. Simultaneous feeding of garlic protein (GP) or soy protein (SP) (500 mg/kg body weight/day for 45 days) to alcohol fed groups increased each of above parameters significantly towards normal values. Increase in GSH content and catalase activity in liver, was significantly higher for SP treated group than for GP treated group. However, increase in plasma LCAT was significantly higher for GP treated group than for SP treated group. Alcohol fed rats showed significant increase in liver weight, serum and tissue cholesterol, serum triacylglycerol (TAG), phospholipids (PL) and free fatty acid (FFA) levels and activity of HMGCoA reductase in liver and intestine. Lipid peroxidation, glucose-6 phosphate dehydrogenase (G6PD), glutathione peroxidase (GPx) and glutathione reductase (GR) in liver and incorporation of labeled acetate into liver cholesterol also showed significant increase. GP and SP treated rats showed decrease in these values towards normal. GP feeding showed a better effect than SP in lowering serum and heart total cholesterol, and in maintaining GPx at near normal level, while SP feeding showed a better effect in lowering serum FFA level and maintaining GR activity at near normal level. In suppressing incorporation of labeled acetate into serum cholesterol, GP feeding showed a better effect than SP. Antiatherogenic and antiperoxidative effects of these proteins may be due to lower lysine/arginine ratio.

A study on the hypoglycemic and hypolipidemic effects of an ayurvedic drug Rajanyamalakadi in diabetic patients.

A study was undertaken for evaluating the hypoglycemic and hypolipidemic effects of an ayurvedic medicine "Rajanyamalakadi" containing Curcuma longa, Emblica officinalis and Salacia oblonga in type II diabetic patients over a period of 3 months. Ethical committee consent for the study was given by the Director, Indian Systems of Medicine, Kerala. A total of 43 patients with established diabetes mellitus as adjudged from clinical features and FBS values, appeared for the camp (Age group 35-75 yrs). An informed consent for the study was obtained from each patient. The clinical proforma was given to each patient to collect data such as height, weight, diet pattern, previous history of illness etc. The ongoing antidiabetic medications were stopped under medical supervision and the patients were provided with 'Rajanyamalakadi' tablets (dose 1-2 tablets each weighing 500mg). The dosage of the drug was decided by the supervising medical officer on a case to case basis, taking note of the clinical conditions and responsiveness of the patients. The patients were monitored for three months, who were divided into 6 groups based on their age and again into two groups, 5 & 6, based on their mean FBS values. ie; Normal Persons, Diabetics of age groups 35-45yrs, 46-55yrs, >55yrs and those with FBS < 145.9 mg% and > 145.9 mg%. The Ayurvedic medicine "Rajanyamalakadi" has showed significant antidiabetic, hypolipidemic and antioxidant effects. In addition to that significant ameliorating effects on the elevated serum AST and ALT activities were also demonstrated by the treatment. The nutraceuticals present in the drug like Terpenoids, Polyphenols, Curcumin etc are responsible for the medicinal effects.

Effects of insulin, glimepiride and combination therapy of insulin and metformin on blood sugar and lipid profile of NIDDM patients.

In the present study the efficacies of therapy with insulin, sulphonylurea or insulin + metformin on NIDDM patients are compared. One group which was on a definite dose of insulin therapy, but with uncontrolled diabetes was treated by doubling the insulin dose, a second group whose diabetes was not controlled by glibenclamide was switched over to another sulphonylurea viz; glimepiride and a third group whose diabetes was not controlled by insulin therapy was switched over to a combination therapy with insulin +metformin. After recording their initial blood parameters all the groups were treated as above for 3 months, and the parameters were again determined. The fasting blood sugar and serum lipids of the first group were controlled significantly, but the values were far above normal range. However HDL Cholesterol and atherogenic index were near normal range. In glimepiride treated group, none of the parameters showed any amelioration. In the combined therapy group, control of blood sugar and atherogenic index was more or less the same as for group 1, but hyperlipidemia remained slightly above that of the same. From the findings we can infer that in long term diabetes treatment higher doses of insulin and combined therapy with insulin and metformin may be more beneficial than with low doses of insulin or sulfonyl urea alone.

Lipid lowering effect of S-methyl cysteine sulfoxide from Allium cepa Linn in high cholesterol diet fed rats.

The lipid lowering action of S-methyl cysteine sulfoxide (SMCS) isolated from Allium cepa Linn (family: Liliaceae) was investigated in Sprague-Dawley rats fed on 1% cholesterol diet, in comparison to the hypolipidemic drug gugulipid. Administration of SMCS at a dose of 200mg/kg body weight for 45 days ameliorated the hyperlipidemic condition. The lipid profile in serum and tissues showed that concentrations of cholesterol, triglyceride and phospholipids were significantly reduced when compared to their untreated counterparts. The total lipoprotein lipase activity in the adipose tissue was decreased with also a decrease in the free fatty acid levels in serum and tissues. The activities of the lipogenic enzymes glucose 6-phosphate dehydrogenase and malic enzyme as also of HMG CoA reductase in the tissues remained low on treatment indicating that both the drugs did not favor lipogenesis and cholesterogenesis in the hyperlipidemic animals. The fecal excretion of bile acids and sterols was further increased upon treatment with the drugs. The results are directive to that both gugulipid and SMCS cause reduction of endogenous lipogenesis, increase catabolism of lipids and subsequent excretion of metabolic by-products through the intestinal tract. However, gugulipid is a better drug than SMCS at a low dose of 50mg/kg body weight.

A comparative study on the effects of diet and exercise, metformin and metformin+pioglitazone treatment on NIDDM patients.

A comparative study on two groups of newly diagnosed nonobese and obese NIDDM patients who were 15 in each group and treated by diet cum exercise and metfromin monotherapy respectively and a third group of 15 obese NIDDM patients whose hyperglycemia was not first controlled by a combination therapy of metformin and sulfonylurea and therefore changed over to a different combination therapy of metformin and ploglitazone, was carried out before and after a period of three months treatment. The mild hyperglycemia in the 1(st) group and the moderate or severe hyperglycemia with accompanied disorders of serum enzymes such as AST, ALT, GGT and the level of HBA(10) observed with 2(nd) and 3(rd) groups of obese NIDDM patients were significantly ameliorated by the respective mode of treatments. Here the efficacies of the three types of treatment are substantiated and further it specifically depicts the success with the choice of combination therapy with metformin and pioglitazone in the third group of obese diabetics.

Nutraceutical effects of garlic oil, its nonpolar fraction and a Ficus flavonoid as compared to vitamin E in CCl4 induced liver damage in rats.

Carbon tetrachloride feeding (3.2g/kg/72hr) for one month increased significantly the serum and tissue lipid profile and deranged the enzyme levels viz; alkaline phosphatase, alanine transaminase, aspartate transaminase, glutathionze reductase, HMGCoA reductase, catalase, gluc.6.PDH and malic enzyme in rats. Simultaneously the lipid peroxidation level in liver was also raised. On administration of garlic oil and its major nonpolar fraction (NPFGO) and a flavonoid isolated from the bark of Ficus bengalensis Linn, viz; leucopelargonin derivative respectively to different groups(100mg/kg/day) the deleterious effects of CCl4 were significantly ameliorated. The liver damage by CCl4 was satisfactorily prevented by these samples as effectively as Vit. E (50 mg/kg/day). The results prove that important nutraceuticals (phytonutrients) like bioflavonoids and theols i.e. allylic sulphide rich fractions give protection from toxins like CCl4. The order of beneficial effects of the drugs are Leucopelargonin > NPFGO > Garlic oil and their effects are comparable to that of vitamin E used at a minimal dose.

Beneficial effects of a polar fraction of garlic (Allium sativum Linn) oil in rats fed with two different high fat diets.

Feeding a diet containing 20% of sesame oil (SO) or coconut oil (CNO) along with 2% cholesterol to rats for two months showed differences in their serum and tissue lipid profile and certain enzyme activities. Hyperlipidemia and related oxidative effects were more pronounced in coconut oil fed rats than those fed sesame oil. Feeding a combination of the oils (10% CNO +10% SO) lowered significantly the hyperlipidemia and certain other deleterious effects of CNO. Feeding a polar fraction of garlic oil (PFGO) prepared in the same way as for ajoene and administered at a dosage of 100 mg/kg along with each of the above oil containing diets counteracted significantly the hyperlipidemic, oxidant and also most of the other deleterious effects of the oils like raised lipid levels in serum and tissues, raised serum levels of AST and tissue levels of HMGCoA reductase and the lowered serum and tissue levels of glutathione reductase. The results support the claims that ajoene, the major polar compound of garlic oil, has very good biological action, which warrants further study.

A comparative study of antioxidants S-allyl cysteine sulfoxide and vitamin E on the damages induced by nicotine in rats.

The dietary consumption of antioxidant-rich fruits and vegetables is inversely correlated with the incidence of various diseases like cardiovascular diseases and lung cancer. We have tried to find out how far the S-allyl cysteine sulfoxide (SACS) isolated from garlic (Allium Sativum L.) can combat the nicotine-induced peroxidative damage in rats. The effects have been compared with the standard antioxidant vitamin E. Administration of SACS or vitamin E (100 mg/kg) to nicotine (0.6 mg/kg) treated rats for 21 days showed decreased concentrations of thiobarbituric acid reactive substances, hydroperoxides, and conjugated dienes in liver, lungs, and heart as compared with the values found in rats treated with nicotine alone. The activities of catalase and superoxide dismutase increased. The levels of the antioxidants like vitamins A, C, and E in the liver and glutathione in all tissues increased significantly in SACS-treated or vitamin E fed rats. However, the antioxidant status was higher when vitamin E was administered as compared with SACS administered to nicotine-treated rats.

Mechanism of action of antiatherogenic and related effects of Ficus bengalensis Linn. flavonoids in experimental animals.

One month treatment of alloxan diabetic dogs with a glycoside, viz. leucopelargonin derivative (100 mg/kg/day) isolated from the bark of F. bengalensis decreased fasting blood sugar and glycosylated haemoglobin by 34% and 28% respectively. Body weight was maintained in both the treated groups while the same was decreased significantly by 10% in the control group. In cholesterol diet fed rats, as the atherogenic index and the hepatic bile acid level and the faecal excretion of bile acids and neutral sterols increased, the HMGCoA reductase and lipogenic enzyme activities in liver and lipoprotien lipase activity in heart and adipose tissue and plasma LCAT activity and the incorporation of labelled acetate into free and ester cholesterol in liver decreased significantly. On treatment with the two ficus flavonoids, viz. leucopelargonin and leucocyanin derivatives and another flavonoid quercetin (100 mg/kg/day) the above said effects except on bile acids and sterols and lipogenic enzymes were significantly reversed in the cholesterol fed rats. However in the treated rats the hepatic level of bile acids and the faecal excretion of bile acids and neutral sterols still further increased and the action of lipogenic enzyme glucose 6 phosphate dehydrogenase was still further decreased. These effects of leucopelargonidin and quercetin were better than that of the second. Toxicity studies are required to be carried out to find out if the ficus flavonoids could be used as health promoters as they are hypocholesterolemic and antioxidant in action.

Antidiabetic and antioxidant effects of S-methyl cysteine sulfoxide isolated from onions (Allium cepa Linn) as compared to standard drugs in alloxan diabetic rats.

Antidiabetic and antoxidant effects of S-methyl cysteine sulfoxide (SMCS) isolated from A. cepa and two standard drugs, glibenclamide and insulin were studied and compared in alloxan diabetic rats after using each of them for treatment for two months. These drugs ameliorated the diabetic condition significantly, viz. maintenance of body weight and control of blood sugar in rats. Further they lowered the levels of malondialdehyde, hydroperoxide and conjugated dienes in tissues exhibiting antioxidant effect on lipid peroxidation in experimental diabetes. This is achieved by their stimulating effects on glucose utilization and the antioxidant enzymes, viz. superoxide dismutase and catalase. The probable mechanism of action of SMCS and glibenclamide may be partly dependent on the stimulation of insulin secretions and partly due to their individual actions. In the amelioration of diabetes the standard drugs showed a better action, but as an antioxidant SMCS proved to be a better one.

A comparative study on the beneficial effects of garlic (Allium sativum Linn), amla (Emblica Officinalis Gaertn)and onion (Allium cepa Linn) on the hyperlipidemia induced by butter fat and beef fat in rats.

Three months feeding of butter fat (BUF) and beef (BF) separately as components of diet at a level of 21% by weight for albino rats, significantly raised their serum and tissue lipids, lipid peroxidation and activities of certain enzymes. BUF was found to be more atherogenic than BF. On incorporation of 5% garlic, amla or onion separately in the above diets, each of them ameliorated the deleterious effects of the animal fats. A higher hyperlipidemic effect of BUF as compared to that of BF may be due to the fact that the ratio of unsaturated to saturated fats is lower for the former (0.56) than for the latter (0.75) and also that the former is richer in cholesterol content than the latter. The order of the curative effects of the vegetables are garlic>amla>onion. The better hypolipidemic effects and correction of elevated levels of certain enzymes shown by garlic and amla may be due to the facts that they contain comparatively better active principles than that found in onions.

Beneficial effects of garlic (Allium sativum Linn) on rats fed with diets containing cholesterol and either of the oil seeds, coconuts or groundnuts.

Feeding of 2% cholesterol diet increased lipid parameters in serum and tissues of rats during a period of one month. In addition to the above, lipid peroxidation also increased and activities of certain enzymes were significantly altered in the tissues. Similar changes were also observed to a greater extent with diets containing 40% by weight of coconut kernel or groundnut with and without 2% cholesterol. The enzymes studied were HMGCoA reductase, AST, ALT and ALP in tissues and serum as the case may be. In general the atherogenic effects were observed more with groundnut containing diets than those with coconut. Even though the oil from the former is mostly unsaturated and that from the latter is mostly saturated, these analytical criteria do not relate to their atherogenic effects. When 5% garlic was incorporated with any of the high fat diets, the lipid parameters, their peroxidation and alterations in enzyme activities were significantly decreased. These results show that garlic contains some principles that counteract the atherogenicity of the above oil seeds.

Antioxidant effect of onion oil (Allium cepa. Linn) on the damages induced by nicotine in rats as compared to alpha-tocopherol.

The beneficial effects of onion oil as an antioxidant has been assessed in nicotine administered rats by studying whether the peroxidative damage caused by nicotine can be effectively combated with the onion oil and the effects compared to vitamin E, a highly efficient antioxidant. Lipid peroxidation products and antioxidant defence system have been studied in liver, lungs, and heart. The rats were injected with nicotine (0.6 mg/kg body wt.) and simultaneously given onion oil (100 mg/kg body wt.) or vitamin E (100 mg/kg body wt.) for 21 days. Concentration of free fatty acids, TBA reactive substances (TBARS), conjugated dienes and hydroperoxides were significantly increased in the tissues of nicotine treated rats as compared to normal rats. Onion oil supplemented to nicotine treated rats showed increased resistance to lipid peroxidation and the effect was near to that of vitamin E fed rats. The activity of catalase and superoxide dismutase decreased in nicotine treated rats. Antioxidants-glutathione content, vitamin C and retinol showed no significant difference but liver vitamin E content significantly decreased in nicotine treated rats. On onion oil or vitamin E supplementation, the concentration of antioxidants were significantly raised in all the tissues studied, however, a significantly increased concentration of glutathione, vitamin E and retinol was noticed in vitamin E+nicotine treated rats. Thus, these results indicate that onion oil is an effective antioxidant against the oxidative damage caused by nicotine as compared to vitamin E.

Anti-peroxidative and hypoglycaemic activity of salacia oblonga extract in diabetic rats.

Hypoglycaemic activity of a petroleum ether extract of the root bark of Salacia oblonga Wall. (Celastraceae) (SOB) was studied in streptozotocin (STZ) hyperglycaemic rats. In addition, the anti-lipid peroxidative activity of SOB was studied in hyperglycaemic rats. The extract showed significant hypoglycaemia ( p < 0.001), which was supported by an insulin assay. A detailed biochemical study (thiobarbituric acid reactive substances, hydroperoxides, conjugated dienes, glutathione, superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase) in the renal tissue of diabetic animals treated with SOB demonstrated promising anti-lipid peroxidative activity. These results suggest that S. oblonga root bark possesses anti-diabetic and anti-peroxidative principles, and may be of value in the treatment of diabetes and associated renal complications.

Antioxidant role of oils isolated from garlic (Allium sativum Linn) and onion (Allium cepa Linn) on nicotine-induced lipid peroxidation.

Nicotine, a major component of tobacco, is partly responsible for the development of atherosclerosis. It has been suggested that antioxidant nutrients are protective against degenerative diseases. So we have studied the antioxidant effect of oils isolated from onion and garlic on nicotine-induced lipid peroxidation in rat tissues. The lipid peroxidation products and scavenging enzymes were assessed in liver, lungs, heart and kidney. The rats were treated with 0.6 mg nicotine/kg bw and simultaneously given 100 mg garlic or onion oils/kg bw for 21 d. Thiobarbituric acid reactive substances, conjugated dienes and hydroperoxides concentrations were significantly increased in the tissues of nicotine-treated rats. Both the garlic oil and onion oil supplementation to nicotine-treated rats increased resistance to lipid peroxidation. The activities of catalase, superoxide dismutase and glutathione peroxidase decreased in nicotine-treated rats, but there was a trend to increased glutathione content. With garlic oil or onion oil supplementation, nicotine-treated rats had increased activities of antioxidant enzymes and increased concentrations of glutathione. These results indicate that oils of garlic and onion are effective antioxidants against the oxidative damage caused by nicotine.