garlic
[In vivo and in vitro effects of selenium-enriched garlic on growth of human gastric carcinoma cells]

[Article in Chinese]

Tang F, Zhou J, Gu L.

Peking University School of Oncology & Beijing Institute for Cancer Research, Beijing 100034, China.

OBJECTIVE: To compare the effects of selenium-enriched garlic (Se-garlic), garlic, Na2SeO3, and garlic + Na2SeO3 on growth of human gastric carcinoma cells. METHODS: In vivo and in vitro assays were carried out in the cultured human gastric carcinoma cell line MGC803 transplanted in the nude mice by cell count, flow cytometry, Western blot and neoplasm volume measurement. RESULTS: The inhibition effect of garlic was similar to that of Se-garlic, but Na2SeO3 was weaker than Se-garlic. Combination of garlic and Na2SeO3 was stronger than Se-garlic. In flow cytometry assay, the proportion of G1 phase was increased after 24 hour treatment of Se-garlic, garlic and Na2SeO3 in the non-synchronized cells. However, the proportion of S phase was increased in the synchronized cells. The proportion of G2 + M phase was increased both in non-synchronized and synchronized cells on treatment with the combination of garlic and Na2SeO3. The amount of Cdk2-CyclinE complex and Cdk4-CyclinD1 complex was decreased in all treated synchronized cells in immunoprecipitation and immunoblot assays. The growth of MGC803 tumor in male Balb/c nude mice was inhibited by administration of 1.67% of Se-garlic (Se 2 micrograms/g) in diet with an inhibition rate of 29.92% in tumor weight. Treatment of either 0.83% of Se-garlic or 1.67% of garlic or 4.38 micrograms/g of Na2SeO3 (Se 2 micrograms/g) could not appreciably inhibit the growth of tumor. Wrapping of a number of monocytes around the tumor was induced in 62.50% of tumors in 0.83% of the Se-garlic group. CONCLUSION: In vitro, Se-garlic is able to inhibit the growth of MGC803 cell through action of garlic. In vivo, Segarlic is able to inhibit growth of MGC803 tumor in nude mice by being better than garlic and selenite.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11859710&dopt=Abstract garlic



garlic
Dose-dependent induction of endogenous antioxidants in rat heart by chronic administration of garlic.

Banerjee SK, Maulik M, Mancahanda SC, Dinda AK, Gupta SK, Maulik SK.

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

The inhibitory property of garlic on free radical generation and lipid peroxidation has been reported in a number of in vitro studies. However, the in vivo effects of chronic garlic intake on the antioxidant milieu of heart has not been reported. Therefore, the present study was designed to investigate the effect of chronic garlic homogenate administration on myocardial endogenous antioxidants and lipid peroxidation at five different dosage levels (125, 250, 500, 1000 and 2000 mg/kg; B, C, D, E, F groups respectively). Garlic homogenate was administered orally to Wistar albino rats (150-200 gms) of either sex 6 days/week for 30 days. Myocardial TBARS (Thiobarbituric acid reactive substances) and antioxidants such as SOD (Superoxide Dismutase), catalase, GPx (glutathione peroxidase) and GSH (Reduced Glutathione) were estimated and histopathological changes were observed. Group F was excluded after 55% mortality occurred in 15 days. TBARS levels were significantly lower in groups B, C and D than that of control group (A). Catalase was increased significantly in groups C, D and E, whereas SOD increased significantly in groups B, C and D but decreased in group E. Significant increase in GSH in group E and significant reduction in GPx activity in group B were observed. Histopathological studies showed marked focal myocytolysis in group E. These results showed that chronic garlic intake dose dependently augmented endogenous antioxidants, which might have important direct cytoprotective effects on the heart, especially in the event of oxidant stress induced injury.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11895102&dopt=Abstract garlic



garlic
Altered cytokeratin expression during chemoprevention of experimental hamster buccal pouch carcinogenesis by garlic.

Balasenthil S, Rao KS, Nagini S.

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

BACKGROUND: Cytokeratins (also known as keratins (K)) are members of the family of intermediate filaments and form major components of the mammalian epithelial cell cytoskeleton. Cytokeratins have emerged as reliable cellular markers of oral cancer development and chemoprevention because of their abundance, stability and high antigenicity. METHODS: We investigated the effect of aqueous garlic extract on cytokeratin expression during 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. Hamsters were divided into four groups of six animals. Animals in group 1 were painted with a 0.5% solution of DMBA in liquid paraffin, on the right buccal pouches, three times a week for 14 weeks. Group 2 animals were painted with DMBA as in group 1 and also received 250 mg/kg body weight aqueous garlic extract orally on alternate days to the DMBA application. Group 3 animals received garlic extract only, as in group 2. Group 4 animals received neither DMBA nor garlic extract and served as the control. The hamsters were killed after an experimental period of 14 weeks. RESULTS: Cytokeratin expression was studied using human monoclonal antibodies AE1 and AE3, which react with type I and II keratins. In DMBA-induced squamous cell carcinomas, decreased expression of high molecular weight keratins was observed. Administration of garlic extract to animals painted with DMBA suppressed HBP carcinomas and restored normal cytokeratin expression. CONCLUSION: The results of the present study suggest that inhibition of HBP carcinogenesis by garlic may be due to its regulatory effects on differentiation, tumour invasiveness, migratory and metastatic potential. We suggest that one of the mechanisms of tumour inhibition by garlic is an influence on cellular differentiation.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11903819&dopt=Abstract garlic



garlic
Garlic and its active metabolite allicin produce endothelium- and nitric oxide-dependent relaxation in rat pulmonary arteries.

Ku DD, Abdel-Razek TT, Dai J, Kim-Park S, Fallon MB, Abrams GA.

Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Alabama 35294, USA. DavidKu UAB.EDU

1. The aims of the present study were to investigate the effects of fresh garlic and one of its active metabolites, allicin, on rat isolated pulmonary arteries (RPA). 2. In endothelium-intact and phenylephrine-precontracted RPA, the addition of a water or a 5% ethanol extract of fresh garlic (1-500 microg/mL) resulted in a dose-dependent relaxation reaching a maximum (mean +/- SEM) of -91 +/- 3 and -93 +/- 2%, respectively, with an ED(50) of 113 +/- 12 and 106 +/- 10 microg/mL, respectively. The vasorelaxation was readily reversible upon washing and no tachyphylaxis was noted. 3. An extract of the external garlic storage leaf produced a significantly greater relaxation than the inner stem. Microfiltration of extracts with a 10,000 molecular sieve did not attenuate relaxation. Inactivation of alliinase and allicin formation, with either boiling of the garlic clove for 30 min or 100% ethanol treatment, completely abolished relaxation. In contrast, similar treatment of crushed garlic with formed allicin retained the relaxation response. 4. Pure allicin produced a similar relaxation as garlic extract, with an EC(50) of approximately 0.8 microg/mL. Disruption of endothelium or N(G)-nitro-L-arginine methyl ester pretreatment attenuated the relaxation, whereas indomethacin had no effect. 5. Prior garlic (500 microg/mL) treatment enhanced acetylcholine relaxation by shifting the response curve to the left, but had no effect on nitric oxide (NO) donor-induced responses. 6. These results demonstrate that garlic and the active metabolite allicin are capable of eliciting a NO-dependent relaxation in RPA and that this response is likely to be mediated via garlic activation of NO formation rather than its stabilization.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11906464&dopt=Abstract garlic



garlic
Allixin accumulation with long-term storage of garlic.

Kodera Y, Ayabe M, Ogasawara K, Yoshida S, Hayashi N, Ono K.

Healthcare Institute, Wakunaga Pharmaceutical Co., Ltd., Japan. kodera_y wakunaga.co.jp

Extremely high accumulation of allxiin, a phytoalexin derived from garlic, was observed in necrotic tissue areas after long-term storage. The allixin produced recrystallized on the surface of the garlic clove. The amount of allixin produced in raw garlic with necrotic tissue areas was 1400 ng/mg wet garlic, which exceeds the minimum exhibitory concentration of allixin. After approximately 2 years of storage, amount of allixin accumulated reached slightly less than 1% of the dry weight of garlic cloves.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11911208&dopt=Abstract garlic