garlic
Garlic and associated allyl sulfur components inhibit N-methyl-N-nitrosourea induced rat mammary carcinogenesis.

Schaffer EM, Liu JZ, Green J, Dangler CA, Milner JA.

Department of Nutrition, The Pennsylvania State University, University Park 16802, USA.

Our previous studies demonstrated that dietary garlic powder supplementation inhibits N-nitrosamine induced DNA alkylation in liver and mammary tissue. The present studies compared the impact of dietary supplementation with garlic powder or two garlic constituents, water-soluble S-allyl cysteine (SAC) and oil-soluble diallyl disulfide (DADS), on the incidence of mammary tumorigenesis induced by N-methyl-N-nitrosourea (MNU). Female Sprague-Dawley rats were fed semi-purified casein based diets with or without supplements of garlic powder(20g/kg), SAC (57 micromol/kg) or DADS (57 micromol/kg) for 2 weeks prior to treatment with MNU (15 mg/kg body wt). Garlic powder, SAC and DADS supplementation significantly delayed the onset of mammary tumors compared to rats receiving the unsupplemented diet. Tumor incidence 23 weeks after MNU treatment was reduced by 76, 41 and 53% in rats fed garlic, SAC and DADS, respectively, compared to controls (P<0.05). Total tumor number was reduced 81, 35 and 65% by these supplements, respectively (P<0.05). In a separate study the quantity of mammary DNA alkylation occurring 3 h after MNU treatment was reduced in rats fed garlic, SAC or DADS (P<0.05). Specifically, O(6)-methylguanine adducts were reduced by 27, 18 and 23% in rats fed supplemental garlic, SAC and DADS, respectively, compared to controls. N(7)-Methylguanine adducts decreased by 48, 22 and 21% respectively, compared to rats fed the control diet. These studies demonstrate that garlic and associated allyl sulfur components, SAC and DADS, are effective inhibitors of MNU-induced mammary carcinogenesis.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8603370&dopt=Abstract garlic



garlic
Dietary components modify the ability of garlic to suppress 7,12-dimethylbenz(a)anthracene-induced mammary DNA adducts.

Amagase H, Schaffer EM, Milner JA.

Department of Nutrition, The Pennsylvania State University, University Park 16802, USA.

Various dietary components were evaluated as factors influencing garlic's ability to depress rat mammary cell DNA adducts resulting from 7,12-dimethylbenz(a)anthracene (DMBA) treatment. Diets with or without garlic powder (20 g/kg) were provided for 2 wk before DMBA treatment (25 mg/kg body weight). Rats fed diets containing 36 g casein/100 g diet had 31% fewer (P < 0.05) mammary cell DNA adducts than those fed 12 g/100 g. Garlic supplementation significantly (P < 0.05) reduced DNA adducts in rats fed either 12 or 36 g casein/100 g by 35 and 32% respectively. In the absence of dietary garlic, DNA adducts were 23% lower (P < 0.05) in rats provided a diet containing supplemental L-methionine at 0.9 g/100 g than at 0.3 g/100 g. However, adduct inhibition by garlic supplementation was greater in rats fed the lower (P < 0.05) amount of methionine (54 vs. 26% inhibition). Adduct levels in rats fed diets with 20 g corn oil/100 g were twice those occurring in rats fed 5 g/100 g (P < 0.05), regardless of adjustment for energy density. Garlic supplementation prevented the increase in DNA adducts caused by increasing dietary corn oil. Combining dietary supplements of garlic, selenite (0.5 mg/kg diet) and retinyl acetate (328 mg/kg diet) inhibited the occurrence of DNA adducts to a greater degree than when each was supplied individually. These studies demonstrate that while dietary garlic can reduce DNA adduct formation in mammary tissue caused by DMBA, this protection is influenced by several dietary components.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8613883&dopt=Abstract garlic



garlic
A prospective cohort study on the relationship between onion and leek consumption, garlic supplement use and the risk of colorectal carcinoma in The Netherlands.

Dorant E, van den Brandt PA, Goldbohm RA.

Department of Epidemiology, University of Limburg, Maastricht, The Netherlands.

The association between onion and leek consumption, garlic supplement use and colon and rectum carcinoma among men and women was evaluated in the Netherlands Cohort Study, a large-scale prospective cohort study on diet and cancer. Onions, leeks, and garlic belong to the Allium genus and contain large amounts of potentially chemopreventive compounds. The Netherlands Cohort Study was started in 1986 among 120 852 men and women, aged 55-69 years. Dietary intake was measured with a 150-item food frequency questionnaire. After 3.3 years of follow-up, 150 and 143 incident male and female cases of colon carcinoma, and 93 and 57 cases of rectum carcinoma, respectively, with complete dietary data were available for analysis. Dietary data were available for 1525 men and 1598 women of a randomly selected subcohort, that was followed up to estimate person-time in the entire cohort. In men, the adjusted rate ratios (RRs) in multivariable analysis for colon and rectum carcinoma in the highest compared to the lowest onion consumption categories were 0.87 (95% confidence interval [CI] = 0.48-1.65), and 0.66 (95% CI = 0.28-1.52), respectively. The RRs for proximal colon carcinoma were lower than for distal colon carcinoma. Leek consumption was not associated with colon and rectum carcinoma incidence in men. None of the RRs were significantly different from unity and no trends in the RRs were detected. A lower risk was found for rectum carcinoma in women consuming less than 0.25 onions per day (RR=0.36, 95% CI = 0.13-0.99), but the trend in the RRs was not statistically significant (P = 0.25). All other RRs for colon and rectum carcinoma associated with onion consumption were slightly higher than one. Leek consumption was not associated with colon and rectum carcinoma incidence. The use of garlic supplements was not associated with colon and rectum carcinoma in men and women combined. This study does not support an inverse association between the consumption of onions and leeks, or the use of garlic supplements and the incidence of male and female colon and rectum carcinoma.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8631133&dopt=Abstract garlic



garlic
Histopathological effects of garlic on liver and lung of rats.

Alnaqeeb MA, Thomson M, Bordia T, Ali M.

Department of Zoology, Faculty of Science, Kuwait University.

The comparative toxic effects of oral and intraperitoneal administration of garlic extracts on lung and liver tissue of rats were studied. Administration of low doses of garlic (50 mg/kg) to rats either orally or intraperitoneally had little effect on lung and liver tissues as compared to control animals. In contrast, administration of high doses of garlic (500 mg/kg) resulted in profound changes in lung and liver tissues of rats. Intraperitoneal administration of the high dose of garlic was more damaging to lung and liver tissue of rats than oral administration.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8644128&dopt=Abstract garlic



garlic
Hypolipidemic effect of garlic protein substituted for casein in diet of rats compared to those of garlic oil.

Mathew BC, Daniel RS, Augusti KT.

Department of Biochemistry, University of Kerala, Thiruvananthapuram, India.

Garlic (Allium sativum Linn.) is ascribed with many therapeutic effects. For the present study, the water soluble proteins and the essential oil of garlic were investigated for their hypolipidemic effect on hyperlipidemia induced by cholesterol containing diet in albino rats. Both garlic protein (16% of diet) and garlic oil (100 mg/kg body weight/day) exhibited significant lipid lowering effects. The hypolipidemic action is primarily due to a decrease in hepatic cholesterogenesis in the treated rats. Even though garlic oil was found to be more effective, the garlic protein is more palatable and free from an obnoxious smell.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8698422&dopt=Abstract garlic