garlic
Expression of c-fos in the main olfactory bulb of neonatal rabbits in response to garlic as a novel and conditioned odour.

Allingham K, Brennan PA, Distel H, Hudson R.

Institut fur Medizinische Psychologie, University of Munich, Munchen, Germany. karl imp.med.uni-muenchen.de

Expression of c-Fos was examined in the olfactory bulbs of 3-day-old rabbits after they had been presented with the odour of garlic as a novel stimulus, as a learned odour, or during conditioning, and this expression compared with baseline levels in non-stimulated controls. Exposure to garlic odour resulted in substantial and widespread increases in c-Fos expression in the olfactory bulbs of all animals. However, although conditioned pups showed a specific behavioural response to the learned garlic odour, neither the amount nor pattern of c-Fos expression differed compared to pups exposed to garlic as a novel odour. The odour-induced expression of c-Fos was not well localised, although there was a significant increase in the number of granule cells expressing c-Fos in the ventrolateral region of the bulb. These results support previous reports that the response to odours in the olfactory bulb of new-born animals is not as spatially distinct as that in adults. Nevertheless, the immature olfactory system of these young animals is clearly capable of very specific odour learning.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11125735&dopt=Abstract garlic



garlic
Antimicrobial properties of garlic oil against human enteric bacteria: evaluation of methodologies and comparisons with garlic oil sulfides and garlic powder.

Ross ZM, O'Gara EA, Hill DJ, Sleightholme HV, Maslin DJ.

St. George's University, St. George's, Grenada, West Indies, United Kingdom.

The antimicrobial effects of aqueous garlic extracts are well established but those of garlic oil (GO) are little known. Methodologies for estimating the antimicrobial activity of GO were assessed and GO, GO sulfide constituents, and garlic powder (GP) were compared in tests against human enteric bacteria. Test methodologies were identified as capable of producing underestimates of GO activity. Antimicrobial activity was greater in media lacking tryptone or cysteine, suggesting that, as for allicin, GO effects may involve sulfhydryl reactivity. All bacteria tested, which included both gram-negative and -positive bacteria and pathogenic forms, were susceptible to garlic materials. On a weight-of-product basis, 24 h MICs for GO (0.02 to 5.5 mg/ml, 62 enteric isolates) and dimethyl trisulfide (0.02 to 0.31 mg/ml, 6 enteric isolates) were lower than those for a mixture of diallyl sulfides (0.63 to 25 mg/ml, 6 enteric isolates) and for GP, which also exhibited a smaller MIC range (6.25 to 12.5 mg/ml, 29 enteric isolates). Viability time studies of GO and GP against Enterobacter aerogenes showed time- and dose-dependent effects. Based upon its thiosulfinate content, GP was more active than GO against most bacteria, although some properties of GO are identified as offering greater therapeutic potential. Further exploration of the potential of GP and GO in enteric disease control appears warranted.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11133485&dopt=Abstract garlic



garlic
Thromboxane-B2, prostaglandin-E2 and hypertension in the rat 2-kidney 1-clip model: a possible mechanism of the garlic induced hypotension.

Al-Qattan KK, Khan I, Alnaqeeb MA, Ali M.

Department of Biological Sciences, Faculty of Science, Kuwait University, P.O. Box 5969, Al-Safat 13060, Kuwait. qattan kuc01.kuniv.edu.kw

Serum collected from unilaterally clipped and unclipped rats before and after treatment with water, garlic or cilazapril and subsequent to measuring blood pressure was assayed for thromboxane-B2 and prostaglandin-E2. The unclipped rats' thromboxane-B2 and prostaglandin-E2 levels were about 23 ng/ml and 2 ng/ml, respectively, and blood pressure was 126+/-3 mmHg. These values were not affected by either water or garlic administration. The clipped rats' thromboxane-B2 and prostaglandin-E2 concentrations were close to 34 ng/ml and 4 ng/ml, respectively, and declined only in response to garlic (by 15 ng/ml and 3 ng/ml) and cilazapril (by 12 ng/ml and 1.5 ng/ml). The blood pressure of these rats was 196+/-7 mmHg and again was reduced only by garlic to 169+/-14 mmHg and cilazapril to 137+/-5 mmHg. The no-treatment and water-treatment readings were significantly higher in the clipped rats. The data suggest that prostanoid system activity in the 2-kidney 1-clip rat is enhanced and mostly toward maintaining the hypertension. Furthermore, the blood pressure lowering effects of garlic and cilazapril might have been induced partially by a greater reduction in the synthesis of vasoconstrictor prostanoids. Copyright 2001 Harcourt Publishers Ltd.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11161580&dopt=Abstract garlic



garlic
Post-transcriptional control of catalase expression in garlic-treated rats.

Pedraza-Chaverri J, Granados-Silvestre MD, Medina-Campos ON, Maldonado PD, Olivares-Corichi IM, Ibarra-Rubio ME.

Department of Biology, Faculty of Chemistry, National Autonomous University of Mexico UNAM, Mexico.

Regulation of catalase (CAT) expression, a major antioxidant enzyme that detoxifies H2O2, is very complex. Garlic is effective to prevent or ameliorate oxidative stress probably through its intrinsic antioxidant properties and/or to its ability to modify antioxidant enzyme expression. In this paper we studied the effect of a 2% garlic diet on the renal and hepatic CAT expression (mRNA levels, and enzyme activity, content, synthesis, and degradation). The study was made 2 weeks after feeding rats with a 2% garlic diet. CAT activity and content were measured by a spectrophotometric method and Western blot, respectively. CAT mRNA levels and CAT synthesis (k(s)) and degradation (kD) in vivo were measured by Northern blot and kinetic of reappearance of CAT activity after aminotriazole injection, respectively. Garlic-treatment decreased CAT activity and content, and CAT mRNA levels were unchanged in both tissues. k(s) decreased and kD remained unchanged in kidney and liver. The decrease in k(s) without changes in kD and CAT mRNA levels could explain the low CAT expression in garlic-fed rats. In vivo H2O2 generation in kidney and liver was markedly decreased in garlic-fed rats which could be due to a direct antioxidant effect of garlic. This may be the initial event in the garlic-fed rats that leads to the decreased CAT expression. Our data strongly suggest that the diminished renal and hepatic CAT expression in garlic-fed rats is mediated by post-transcriptional changes (mainly low translational efficiency) which could be an adaptation to the low H2O2.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11216869&dopt=Abstract garlic



garlic
The determination of metabolites of garlic preparations in breath and human plasma.

Rosen RT, Hiserodt RD, Fukuda EK, Ruiz RJ, Zhou Z, Lech J, Rosen SL, Hartman TG.

Center For Advanced Food Technology, Rutgers University, New Brunswick, NJ 08901, USA.

Gas Chromatography-Mass Spectrometry (GC-MS) was the major technique used to determine various metabolites after consumption of dehydrated granular garlic and an enteric-coated garlic preparation, in breath, plasma, and simulated gastric fluids. A special short-path thermal desorption device was used as an introduction technique for the gas chromatograph for the determination of volatiles. These garlic preparations release allicin, which decomposes in stomach acid or with time in the intestine to release allyl sulfides, disulfides and other volatiles, some of which are postulated to be metabolized by glutathione and/or S-adenosylmethionine to form allyl methyl sulfide, the main sulfur containing volatile metabolite. S-Allylcysteine, a non-volatile bioactive component of aged garlic preparations, was determined in human plasma and urine by HPLC-MS using the negative ion atmospheric pressure chemical ionization mode (APcI)- MS. The technique of selected ion monitoring was used for quantitation. A synthetic internal standard of deuterated S-allylcysteine was added to the plasma or urine to ensure recovery and to obtain reliable quantitative data.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11237188&dopt=Abstract garlic