garlic
Prevention of 4-nitroquinoline 1-oxide-induced rat tongue carcinogenesis by garlic.

Balasenthil S, Ramachandran CR, Nagini S.

Department of Biochemistry, Faculty of Science, Annamalai University, Annamalainagar-608 002, Tamil Nadu, India.

The present study was undertaken to examine the inhibitory effect of garlic (Allium sativum) on 4-nitroquinoline 1-oxide (4NQO)-induced tongue carcinogenesis in male rats, both in the initiation and post-initiation phases. Lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (GPx), and glutathione S-transferase (GST) were used to monitor the chemopreventive potential of garlic. Biochemical estimations were carried out on tumour and normal tongue tissues. Diminished lipid peroxidation in the tumour tissue was accompanied by a significant increase in the levels of GSH, GPx and GST. Administration of garlic (250 mg/kg, p.o., three times a week) effectively suppressed 4NQO-induced tongue carcinogenesis as revealed by the absence of carcinomas in the initiation phase and their reduced incidence in the post-initiation phase. The results of the present study suggest that garlic may exert its chemopreventive effects by modulating lipid peroxidation and enhancing the levels of GSH, GPx and GST.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11429247&dopt=Abstract garlic



garlic
Garlic-induced alteration in rat liver and kidney morphology and associated changes in endogenous antioxidant status.

Banerjee SK, Maulik M, Manchanda SC, Dinda AK, Das TK, Maulik SK.

Department of Pharmacology, All India Institute of Medical Sciences, 110029, New Delhi, India.

The effects of chronic garlic intake on various endogenous antioxidant enzymes and lipid peroxidation on two major organs, the liver (L) and kidneys (K), were investigated. Wistar albino rats were fed with fresh garlic homogenate daily by gavage in three different doses (250, 500 and 1000 mg/kg/day) for 30 days. After this period, rats were sacrificed and liver and kidneys were harvested for biochemical estimation. In comparison to saline-treated rats, the 250 mg/kg/day dose significantly (P<0.02) reduced thiobarbituric acid reactive substances (TBARS) (L: 187.48+/-9.23 vs 150.66+/-11.45; K: 177.38 15.88 vs 120.66+/-9.39 nmol/g wet. weight) and glutathione peroxidase (GPx) (L: 0.2438+/-0.05 vs 0.0046+/-0.0005; K: 0.1459+/-0.034 vs 0.0055+/-0.0003 U/mg protein). There was no change in catalase and reduced glutathione (GSH) but superoxide dismutase (SOD) increased significantly (P<0.01) (L: 5.49+/-0.76 vs 18.38+/-2.26; K: 11.47+/-1.48 vs 21.22+/-3.19 U/mg protein). Both 500 and 1000 mg/kg/day doses significantly (P<0.05) reduced endogenous antioxidants (catalase and SOD) without altering TBARS. A 1000 mg/kg/day dose of garlic caused marked histopathological and ultrastructural changes in both liver and kidneys. The results suggest that garlic in low doses has the potential to enhance the endogenous antioxidant status, although at higher doses a reversal of these effects is observed. The present study also highlights the potential ability of a high dose of garlic to induce morphological changes in the liver and kidneys, indicating the need to identify a safe dose range for garlic.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11434986&dopt=Abstract garlic



garlic
[The experimental study of the anti-enterovirus effects of drugs in vitro]

[Article in Chinese]

Luo R, Dong Y, Fang F.

Shiyan People's Hospital, Hubei 442000, China.

OBJECTIVE: To screen the safe and effective anti-enterovirus drugs for clinical application. METHODS: The cytotoxicity of Ribavirin, Shuanghuanglian and Garlic were evaluated through MTT colorimetry and cell morphology. The antiviral activity of Ribavirin, Shuanghuanglian and Garlic were studied in HEL and Vero cells infected with CBV3 and ECHO11 by observing cytopathic effect (CPE), MTT colorimetry and plaque-reduction assay. The antiviral activity of these three drugs were compared and that of Shuanghuanglian and Garlic were also compared before and after ECHO11 absorbing by plaque-reduction assay. RESULTS: (1) The cytotoxicity of these three drugs were expressed as TC50(50% toxic concentration). TC50 of Ribavirin was 2 mg/ml, of Shuanghuanglian 5 mg/ml, of Garlic 12.5 micrograms/ml. (2) Ribavirin could inhibit CBV3 and ECHO11 at the concentration ranged from 1 mg/ml to 1.5 mg/ml. Shuanghuanglian could inhibit CBV3 and ECHO11 at the concentration of 0.5 mg/ml and the viral inhibiting effect was concentration-dependent. Garlic could inhibit CBV3 and ECHO11 at the concentration ranged from 2.5 micrograms/ml to 7.5 micrograms/ml and 5 micrograms/ml was the most effective. (3) Plaque-reduction assay was used to test the anti-virus (CBV3 and ECHO11) activity of these three drugs: plaque reduction rate of 1.5 mg/ml Ribavirin was 43.2% and 37.2%, of 2.5 mg/ml Shuanghuanglian was 81.1% and 88.4% and of 5 micrograms/ml Garlic was 66.2% and 77.4% respectively. The plaque reduction rate of Ribavirin was lower than the other two drugs (P < 0.05), between these two showed no significant difference (P > 0.05). The anti-ECHO11 activity of Shanghuanglian before ECHO11 adsorbing was higher than after ECHO11 adsorbing (P < 0.05). There was no significant difference between the plaque reduction rates of Garlic before and after ECHO11 adsorbin. CONCLUSION: All of the three drugs have anti-virus activity in vitro while Shuanghuanglian and Garlic are more effective. Among these three drugs, the cytotoxicity of Shuanghuanglian is the most weak and the anti-virus activity is the strongest. The antiviral activity of Shuanghuanglian adding before virus adsorbing was higher, so it seems that Shuanghuanglian can prevent EV infection.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11444254&dopt=Abstract garlic



garlic
Effect of garlic (Allium sativum L.) extract on tissue lead level in rats.

Senapati SK, Dey S, Dwivedi SK, Swarup D.

Laboratory of Comparative System of Medicine, Division of Medicine, Indian Veterinary Research Institute, Izatnagar, 243 122 U.P., India.

The prophylactic efficacy of garlic (Allium sativum L.) extract to reduce tissue lead (Pb) concentration was evaluated experimentally in rats. Thirty female rats were divided into five groups, keeping group A as a healthy control. Rats of groups B, C, D and E received lead acetate orally at the rate of 5 mg per kg body weight daily for 6 weeks. The garlic extract was tried in three doses, viz. 100 (low), 200 (medium) and 400 mg (high) per kg body weight orally and given simultaneously with lead salt to the rats of group C, D and E, respectively. Mean blood lead concentrations in lead-exposed rats ranged between 0.13+/-0.02 and 0.96+/-0.06 microg/ml, whereas in garlic-treated rats, the range was between 0.16+/-0.01 and 0.80+/-0.05; 0.13+/-0.01 and 0.71+/-0.06 and 0.14+/-0.01 and 0.60+/-0.05 microg per ml in low, medium and high dose groups, respectively. The mean lead concentration in liver, kidneys, brain and bone of lead exposed rats was 2.943+/-0.206, 4.780+/-0.609, 1.019+/-0.100 and 44.075+/-2.60 microg per ml, respectively. Concomitant use of garlic extract at the three different doses was found to reduce lead concentration considerably indicating the potential therapeutic activity of garlic against lead.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11448543&dopt=Abstract garlic



garlic
An in vitro evaluation of human cytochrome P450 3A4 and P-glycoprotein inhibition by garlic.

Foster BC, Foster MS, Vandenhoek S, Krantis A, Budzinski JW, Arnason JT, Gallicano KD, Choudri S.

Office of Science, Therapeutic Products Directorate, Health Canada, Ottawa, Ontario, Canada. brian_foster hc-sc.gc.ca

PURPOSE. Garlic has been used as a flavouring agent, traditional medicine, and functional food to improve physical or mental well-being. Garlic and garlic products generally have been regarded as safe but a number of conflicting reports in the literature and confounding factors make it difficult to unequivocally establish the clinical efficacy and safety of these products either alone or in the presence of therapeutic products. A preliminary study was undertaken with fresh garlic and garlic products using the major cDNA-expressed human cytochrome P-450 isozymes associated with the metabolism of HIV/AIDS drugs, and purified P-glycoprotein (P-gp) cell membranes to ascertain the risk potential for generating interactions with therapeutic products. METHODS. A broad screening was undertaken with 10 garlic products (aged, odourless, oil, freeze-dried) and 3 varieties of fresh garlic bulbs (common, Elephant and Chinese), all purchased from local outlets, to examine their potential to affect human cytochrome P-450 2C9*1, 2C9*2, 2C19, 2D6, 3A4, 3A5 and 3A7 mediated-metabolism of marker substrates using an in vitro fluorometric microtiter plate assay. Four garlic products were screened for their potential to interact with P-gp using an in vitro colourmetric ATPase assay. RESULTS. Extracts of fresh garlic, different brands and lots of odourless garlic and representative samples of garlic oil, freeze dried garlic, and aged garlic exhibited an inhibitory effect on cytochrome P450 2C9*1, 2C19, 3A4, 3A5 and 3A7 mediated metabolism of a marker substrate. The activity of 2D6 mediated-metabolism was generally unaffected by garlic. Extracts of the fresh garlic stimulated CYP2C9*2 metabolism of the marker substrate. With the extracts tested, garlic had very low to moderate P-gp interaction as compared with the positive control verapamil. CONCLUSIONS. Our in vitro findings demonstrate that garlic components can affect cytochrome P-450 2C, 2D and 3A mediated-metabolism of the isoforms studied. The safety and efficacy of conventional therapeutic products metabolized by the affected isozymes, particularly those with a narrow therapeutic index, taken concomitantly with garlic needs to be examined further under clinical settings.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11466175&dopt=Abstract garlic