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.     

Antioxidant and anti‐apoptotic effects of onion (Allium cepa) extract on doxorubicin‐induced cardiotoxicity in rats

The aim of this study was to investigate the antioxidant and anti‐apoptotic effects of onion (Allium cepa) extracts (ACE) on doxorubicin (DOX)‐induced cardiotoxicity. The rats in the ACE‐pretreated group were given a daily dose of 1 ml ACE for 14 days. To induce cardiotoxicity, DOX (30 mg kg^?1 body weight) was injected intraperitoneally by a single dose and the rats were sacrificed after 48 h. To date, no such studies have been performed on the cardioprotective and anti‐apoptotic potential of ACE on DOX‐induced cardiotoxicity. Our data indicate a significant reduction in the activity of in situ identification of apoptosis using terminal dUTP nick end‐labeling in cardiomyocytes of the DOX‐treated group with ACE therapy. The DOX‐treated with ACE groups showed a significant decrease in malondialdehyde levels, and increased activities of superoxide dismutase, glutathione and glutathione peroxidase in comparison with the DOX‐treated group. Creatine kinase, creatine kinase MB, lactate dehydrogenase activities and cardiac troponin I levels were significantly decreased in the DOX + ACE group in comparison with the DOX group. These biochemical and histological disturbances were effectively attenuated on pretreatment with ACE. The present study showed that ACE may be a suitable cardioprotector against toxic effects of DOX. Copyright © 2011 John Wiley & Sons, Ltd.     

Hypoglycaemic effects of onion, Allium cepa Linn. on diabetes mellitus - a preliminary report.

Hypoglycaemic fractions of A. cepa Linn (onion) have been separated. After 7 days treatment, the more active hypoglycaemic fraction was about half as active as Phenformin in lowering the fasting blood sugar of alloxan-diabetic rabbits. Oral administration of the hypoglycaemic fraction to alloxan-diabetic rabbits improved their glucose tolerance also. Juice expressed residue of onion, when fed to diabetic patients along with their food, controlled the hyperglycaemia effectively.     

The effects of onion (Allium cepa) extract on doxorubicin‐induced apoptosis in aortic endothelial cells

The aim of this study was to investigate the effects of onion (Allium cepa) extracts (ACE) on doxorubicin (DOX)-induced apoptosis in aortic endothelial cells. The rats in the ACE-pretreated group were given a daily dose of 1 ml ACE for 14 days. To induce aortic endothelial cell apoptosis, DOX (30 mg kg⁻¹ body weight) was injected intraperitoneally by a single dose and the rats were sacrificed after 48 h. To date, no such studies have been performed on antiapoptotic potential of ACE on DOX-induced apoptosis in aortic endothelial cells. Our data indicate a significant reduction in the activity of in situ identification of apoptosis using terminal dUTP nick end-labeling in aortic endothelial cells of the DOX-treated group with ACE therapy. DOX-treated with ACE groups showed a significant decrease in malondialdehyde levels and increased levels of glutathione in comparison with the DOX-treated group. Data from our study show that prevention of endothelial cell apoptosis by ACE may contribute to the restoration of aortic endothelial dysfunction that is associated with DOX treatment. Copyright © 2011 John Wiley & Sons, Ltd.     

The effects of Permethrin and antioxidant properties of Allium cepa (onion) on testicles parameters of male rats

The aim of this study was to evaluate the effects of Permethrin on the testes of adult Wistar rats, and evaluate the efficacy of Onion juice supplementation. The male rats were divided into five groups: I: control; II: DMSO (0/5?ml); III: Permethrin (35?mg/kg) in 0/5?ml DMSO; IV: Permethrin (35?mg/kg)?+?Onion (3?ml); V: onion (3?ml). After 60 days, male rats in all groups prepared to evaluate genital organs weights, the Leydig cells culturing and measurement of testosterone hormone level. Permethrin have negative impacts on Sperm parameters, the Leydig cells count and reduced testosterone serum level in groups 3 and 4. However, in group 4, ONION with antioxidant properties can modify these effects. Onion showed a significant remedy effect on sperm parameters and also leads to increases in the number of Leydig cells. These findings indicated that Permethrin have the negative effects on the reproductive system and fertility.     

Antioxidant activity of phenolic extracts from different cultivars of Italian onion (Allium cepa) and relative human immune cell proliferative induction

Context: The total antioxidant activity (TAC) may vary considerably between onion cultivars. Immunological effects of onion phenolic compounds are still underestimated.

Objective: The objective of this study is to determine the total phenol content (TPC) and the relative TAC of three Allium cepa L. (Liliaceae) onion cultivars cultivated in Cannara (Italy): Rossa di Toscana, Borettana di Rovato, and Dorata di Parma, and to evaluate the phenol extracts ability to induce human immune cell proliferation.

Materials and methods: TPC was determined by the Folin–Ciocalteu method, TAC with FRAP, TEAC/ABTS, and DPPH methods. Peripheral blood mononuclear cells from healthy human donors were incubated for 24?h at 37?°C with 1?ng/mL of phenolic extract in PBS, immunostained, and then analyzed by 4-color flow cytometry for the phenotypic characterization of T helper cells (CD4+ cells), cytotoxic T lymphocytes (CD8+ cells), T regulatory cells (CD25high CD4+ cells), and natural killer cells/monocytes (CD16+ cells).

Results: Rossa di Toscana displayed the highest TPC (6.61?±?0.87?mg GA equivalents/g onion bulb DW) and the highest TAC with the experienced methods: FRAP, 9.19?±?2.54 μmol Trolox equivalents/g onion bulb DW; TEAC/ABTS, 21.31?±?0.41 μmol Trolox equivalents/g onion bulb DW; DPPH, 22.90?±?0.01 μmol Trolox equivalents/g onion bulb DW. Incubation with Rossa di Toscana extract determined an increase in the frequency of the antitumor/anti-infection NK CD16+ immune cells (23.0?±?0.4%).

Discussion and conclusions: Content of health-promoting phenols and the deriving antioxidant and immunostimulating activity vary considerably among the investigated cultivars. Rossa di Toscana can be considered as a potential functional food.     

Characterization of onion lectin (Allium cepa agglutinin) as an immunomodulatory protein inducing Th1-type immune response in vitro

Onion (Allium cepa), a bulb crop of economic importance, is known to have many health benefits. The major objective of the present study is to address the immunomodulatory properties of onion lectin (A. cepa agglutinin; ACA). ACA was purified from onion extract by d-mannose-agarose chromatography (yield: ~ 1 mg/kg). ACA is non-glycosylated and showed a molecular mass of ~ 12 kDa under reducing/non-reducing SDS-PAGE; glutaraldehyde cross-linking indicated that ACA is a non-covalent tetramer of ~ 12 kDa subunits. Its N-terminal sequence (RNVLLNNEGL; UniProt KB Accn. C0HJM8) showed 70–90% homology to mannose-specific Allium agglutinins. ACA showed specific hemagglutination activity of 8200 units/mg and is stable in the pH range 6–10 and up to 45 ° C. The immunomodulatory activity of ACA was assessed using the macrophage cell line, RAW264.7 and rat peritoneal macrophages; at 0.1 μg/well, it showed a significant increase (6–8-fold vs. control) in the production of nitric oxide at 24 h, and significantly stimulated (2–4-fold vs. control) the production of pro-inflammatory cytokines (TNF-α and IL-12) at 24 h. ACA (0.1 μg/well) enhanced the proliferation of murine thymocytes by ~ 4 fold (vs. control) at 24 h; however, ACA does not proliferate B cell-enriched rat splenocytes. Further, it significantly elevated the expression levels of cytokines (IFN-γ and IL-2) over the control in murine thymocytes. Taken together, purified ACA induces a Th1-type immune response in vitro. Though present in low amounts, ACA may contribute to the immune-boosting potential of the popular spice onion since considerable amounts are consumed on a daily basis universally.     

Tolerance to the convulsions induced by daily nicotine treatment in rats.

Development of tolerance to the nicotine-induced convulsions in rats was examined. Acute intraperitoneal (i.p.) administration of nicotine (2.5, 3.75 and 5 mg/kg) produced convulsions in a dose-dependent manner. Mecamylamine (1 mg/kg, i.p.) antagonized the convulsions, but hexamethonium (5 mg/kg, i.p.) did not modify them. Daily nicotine administration (2.5, 3.75 and 5 mg/kg, i.p.) once a day for 6 days developed tolerance to the convulsions induced by nicotine. After the daily administrations of nicotine for 6 days, the effects of a challenge administration of nicotine (2 mg/kg) on the nicotine-induced convulsions were tested on the 7th-day. Further tolerances were also developed by the 7th-day challenge administration. After the 7th-day test, nicotine levels of the brain and blood 15 min after the challenge injection were measured. With nicotine (5 mg/kg once a day)-treatment, nicotine levels of all the brain regions were increased. In contrast, a similar challenge injection had no effect on blood nicotine level. These results indicate that the development of tolerance to the nicotine-induced convulsions is produced relatively earlier and day by day by daily administrations to rats, which is closely related with the increase in brain nicotine level.     

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.     

Potential antioxidant,anticholinergic, antidiabetic and antiglaucoma activities and molecular docking of spiraeoside as a secondary metabolite of onion (Allium cepa)

Onion contains many dietary and bioactive components including phenolics and flavonoids. Spiraeoside (quercetin-4-O-β-D-glucoside) is one of the most putative flavonoids in onion. Several antioxidant techniques were used in this investigation to assess the antioxidant capabilities of spiraeoside, including 1,1-diphenyl-2-picrylhydrazyl radical (DPPH·) scavenging, N,N-dimethyl-p-phenylenediamine radical (DMPD^•+) scavenging, 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonate) radical (ABTS^•+) scavenging activities, cupric ions (Cu²⁺) reducing and potassium ferric cyanide reduction abilities. In contrast, the water-soluble α-tocopherol analogue trolox and the conventional antioxidants butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), and α-tocopherol were utilized as the standards for evaluation. Spiraeoside scavenged the DPPH radicals an IC₅₀ of 28.51 μg/mL (r²: 0.9705) meanwhile BHA, BHT, trolox, and α-tocopherol displayed IC₅₀ of 10.10 μg/mL (r²: 0.9015), 25.95 μg/mL (r²: 0.9221), 7.059 μg/mL (r²: 0.9614) and 11.31 μg/mL (r²: 0.9642), accordingly. The results exhibited that spiraeoside had effects similar to BHT, but less potent than α-tocopherol, trolox and BHA. Also, inhibitory effects of spiraeoside were evaluated toward some metabolic enzymes including acetylcholinesterase (AChE), butyrylcholinesterase (BChE), carbonic anhydrase II (CA II) and α-glycosidase, which are related to a number of illnesses, such as Alzheimer’s disease (AD), diabetes mellitus and glaucoma disorder. Spiraeoside exhibited IC₅₀ values of 4.44 nM (r²: 0.9610), 7.88 nM (r²: 0.9784), 19.42 nM (r²: 0.9673) and 29.17 mM (r²: 0.9209), respectively against these enzymes. Enzyme inhibition abilities were compared to clinical used inhibitors including acetazolamide (for CA II), tacrine (for AChE and BChE) and acarbose (for α-glycosidase). Spiraeoside demonstrated effective antioxidant, anticholinergic, antidiabetic and antiglaucoma activities. With these properties, it has shown that Spiraeoside has the potential to be a medicine for some metabolic diseases.     

Potential therapeutic effect of Allium cepa L. and quercetin in a murine model of Blomia tropicalis induced asthma

Background

Asthma is an inflammatory condition characterized by airway hyperresponsiveness and chronic inflammation. The resolution of inflammation is an essential process to treat this condition. In this study we investigated the effect of Allium cepa L. extract (AcE) and quercetin (Qt) on cytokine and on smooth muscle contraction in vitro and its therapeutic potential in a murine model of asthma.

Methods

AcE was obtained by maceration of Allium cepa L. and it was standardized in terms of quercetin concentration using high performance liquid chromatography (HPLC). In vitro, using AcE 10, 100 or 1000 μg/ml or Qt 3.5, 7.5, 15 μg/ml, we measured the concentration of cytokines in spleen cell culture supernatants, and the ability to relax tracheal smooth muscle from A/J mice. In vivo, Blomia tropicalis (BT)-sensitized A/J mice were treated with AcE 100, 1000 mg/kg or 30 mg/kg Qt. We measured cell influx in bronchoalveolar lavage (BAL), eosinophil peroxidase (EPO) in lungs, serum levels of Bt-specific IgE, cytokines levels in BAL, and lung histology.

Results

We observed a reduction in the production of inflammatory cytokines, a relaxation of tracheal rings, and a reduction in total number of cells in BAL and EPO in lungs by treatment with AcE or Qt.

Conclusion

AcE and Qt have potential as antiasthmatic drugs, as they possess both immunomodulatory and bronchodilatory properties.     

瓜蒌皮提取物对大鼠血管内皮损伤的保护作用

目的研究瓜蒌皮提取物（EPT）对低密度脂蛋白（LDL）诱导的血管内皮损伤的保护作用。方法 48只SD大鼠在乙醚麻醉下,舌下静脉注射人血清LDL（4mg/kg）诱发血管内皮功能损伤。检测血中非对称性二甲基精氨酸（ADMA）、丙二醛（MDA）、一氧化氮（NO）和肿瘤坏死因子-α（TNF-α）的含量。结果单次静注LDL（4mg/kg）显著增加血液中ADMA、MDA和TNF-α水平,降低血液中NO水平。用水和70%乙醇洗脱的瓜蒌皮提取物能显著抑制ADMA、MDA和TNF-α浓度升高及增加血液中NO水平。结论瓜蒌皮提取物对LDL诱导的血管内皮细胞损伤有保护作用,其保护作用与降低ADMA浓度有关。     

Antioxidant activity of Albizzia lebbeck (Linn.) Benth. in alloxan diabetic rats

There is an increasing demand for natural anti-diabetic drugs, as continuous oral administration of insulin can culminate in many side effects and toxicity. In our endeavour to formulate some cost-effective herbal medicines for diabetes, we undertook this study to evaluate the antioxidant potential of aqueous extract of Albizzia lebbeck (ALL) in diabetic rats. The oxidative stress in alloxan-induced diabetic rats was determined by estimating the levels of thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD) and reduced glutathione (GSH) in liver and kidneys. Activities of antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione S transferase (GST) were assessed in diabetic as well as rats co-administered with ALL. Oxidative damage in the liver and kidneys of diabetic rats as evidenced by a marked increment in the levels of TBARS and CD, and also a distinct diminution in GSH content was nullified by ALL, as these parameters showed a tendency to retrieve towards normalcy on co-administration of the herbal drug. The antioxidant enzymes registered a decline in activity in diabetic rats thus revealing the damaging effects of free radicals generated due to alloxan exposure. The activities of these enzymes returned to normalcy in ALL-administered rats indicating the antioxidant efficacy of the drug in resisting oxidative insult. The findings provide a rationale for further studies on isolation of active principles and pharmacological evaluation.     

Characteristics of tail-tremor induced by nicotine in rats

To characterize the tail-tremor and locomotor hyperactivity induced by repeated nicotine administration, the effects of nicotinic, -adrenergic and dopaminergic blockers were investigated in rats. Daily administration of nicotine (0.5 mg/kg, s.c.) induced tail-tremor from the 4th day, which became more marked in intensity by subsequent administration. Locomotor hyperactivity was also induced by nicotine, which was enhanced by daily administration. The tail-tremor and locomotor hyperactivity induced by repeated nicotine administration were inhibited by mecamylamine (0.1–1 mg/kg, i.p.) but not by hexamethonium (0.5 and 1 mg/kg, i.p.). Clonidine (0.02 and 0.04 mg/kg, i.p.) and prazosin (0.5 and 1 mg/kg, i.p.) reduced tail-tremor more markedly than hyperactivity. However, haloperidol (0.05–0.2 mg/kg, i.p.) and chlorpromazine (1–5 mg/kg, i.p.) reduced hyperactivity more markedly than tail-tremor. These results suggest that nicotine-induced tail-tremor and hyperactivity are due to an increased susceptibility of central nicotinic receptors of nicotine followed by catecholaminergic mechanisms, and that tail-tremor may be more associated with the noradrenergic system than the dopaminergic system. Correspondence to: Y. Gomita at the above address     

Mitodepressive effect of (-)-cathinone, from Catha edulis (khat), on the meristematic region of Allium cepa root tips

(-)-Cathinone, a psychostimulant alkaloid from khat, showed a significant mitodepressive effect on the dividing cells of Allium cepa root tips. This effect was dose-dependent and irreversible. Exposure of root cell to cathinone for 48 hr produced significant condensation and clumping of chromosomes, sticky metaphases and anaphase bridges. Our study suggests that the teratogenic and mutagenic effects of khat extracts as reported by earlier workers might be partially or totally due to their (-)-cathinone content.     

Hexavalent chromium and its effect on health: possible protective role of garlic (Allium sativum Linn)

Hexavalent chromium or chromium (VI) is a powerful epithelial irritant and a confirmed human carcinogen. This heavy metal is toxic to many plants, aquatic animals, and bacteria. Chromium (VI) which consists of 10%-15% total chromium usage, is principally used for metal plating (H2Cr2O7), as dyes, paint pigments, and leather tanning, etc. Industrial production of chromium (II) and (III) compounds are also available but in small amounts as compared to chromium (VI). Chromium (VI) can act as an oxidant directly on the skin surface or it can be absorbed through the skin, especially if the skin surface is damaged. The prooxidative effects of chromium (VI) inhibit antioxidant enzymes and deplete intracellular glutathione in living systems and act as hematotoxic, immunotoxic, hepatotoxic, pulmonary toxic, and nephrotoxic agents. In this review, we particularly address the hexavalent chromium-induced generation of reactive oxygen species and increased lipid peroxidation in humans and animals, and the possible role of garlic (Allium sativum Linn) as a protective antioxidant.     

Beneficial effect of alpha-tocopherol in renal ischemia-reperfusion in rats.

We evaluated the effects of alpha-tocopherol (vitamin E) on the products of lipid peroxidation and serum creatinine levels in a rat model of renal ischemia-reperfusion. The animals were submitted to sham operation or renal ischemia-reperfusion, and they were pretreated with alpha-tocopherol or the vehicle saline. In four groups, we analyzed the lipid peroxidation products by measuring malondialdehyde and chemiluminescence levels. In the other three groups, we studied the serum creatinine levels after the procedures. In our study, the pretreatment with alpha-tocopherol reduced significantly the lipid peroxidation of renal cells and renal dysfunction induced by renal ischemia-reperfusion in rats.     

Antioxidant effects of heated garlic juice on cadmium-induced liver damage in rats as compared to ascorbic acid

The antioxidant efficacy of heated garlic juice (HGJ) in liver was evaluated with that of ascorbic acid (AA) in rats exposed to acute dose of cadmium (4 mg kg(-1) bd. wt). The rats were either given HGJ (100 mg kg(-1) bd. wt) orally, daily for 4 weeks or AA (100 mg kg(-1) bd. wt) orally, daily for 4 weeks or both or cadmium (4 mg kg(-1) bd. wt) intraperitoneally for 3 days. Another group of rats was given cadmium (4 mg kg(-1) bd. wt) intraperitoneally for 3 days after pretreatment with either HGJ (100 mg kg(-1) bd. wt) or ascorbic acid (100 mg kg(-1) bd. wt) for 4 weeks and the liver excised. The results obtained show that AA and HGJ significantly reduced the level of liver malondialdehyde (MDA) induced by cadmium compared to control (p < 0.05) but AA tends to be more potent when compared with HGJ. The presence of either HGJ or AA also significantly reduced the levels of ROS in the presence of cadmium (Cd). The presence of either AA or HGJ pre-treatment produced significant increase in liver SOD and Catalase activities when compared with rats treated with Cd alone. There was no significant reduction in the activities of these enzymes in the presence of cadmium compared to control. Western blot shows that the expressions of Nrf2 and NQO1 in the liver were significantly increase by 3 and 1.7-fold respectively in the AA pretreated mice when compared with Cd. However no significant changes were seen in HGJ pretreated rats. The expression of HO-1 was not significantly increase in the AA pretreated rats. The results show that though both ascorbic acid and HGJ are efficient in preventing Cd-induced damage in the rat liver, ascorbic acid appeared to be a more powerful antioxidant than heated garlic juice in preventing cadmium-induced oxidative damage in liver and its action may be mediated in parts via Nrf2-keap1 pathway.