Allicin Research Articles

Effect of supplementation of allicin on methanogenesis and ruminal microbial flora in Dorper crossbred ewes.

BackgroundGarlic extracts have been reported to be effective in reducing methanogenesis. Related mechanisms are not well illustrated, however, and most studies have been conducted in vitro. This study investigates the effects of supplementary allicin (AL) in sheep diet on in vivo digestibility, rumen fermentation, and shifts of microbial flora.MethodsTwo experiments were conducted using Dorper × thin-tailed Han crossbred ewes. In experiment 1, eighteen ewes (60.0 ± 1.73 kg BW) were randomly assigned for 29 days to either of two dietary treatments: a basal diet or the basal diet supplemented with 2.0 g AL/head·day to investigate supplementary AL on nutrient digestibility and methane emissions. In experiment 2, six ewes (65.2 ± 2.0 kg BW) with ruminal canulas were assigned to the same two dietary treatments as in experiment 1 for 42 days to investigate supplementary AL on ruminal fermentation and microbial flora. The methane emissions were determined using an open-circuit respirometry system and microbial assessment was done by qPCR of 16S rRNA genes.ResultsSupplementary AL increased the apparent digestibility of organic matter (P < 0.001), nitrogen (P = 0.006), neutral detergent fiber (P < 0.001), and acid detergent fiber (P = 0.002). Fecal nitrogen output was reduced (P = 0.001) but urinary nitrogen output was unaffected (P = 0.691), while nitrogen retention (P = 0.077) and nitrogen retention/nitrogen intake (P = 0.077) tended to increase. Supplementary AL decreased methane emissions scaled to metabolic bodyweight by 5.95 % (P = 0.007) and to digestible organic matter intake by 8.36 % (P = 0.009). Ruminal pH was unaffected (P = 0.601) while ammonia decreased (P = 0.024) and total volatile fatty acids increased (P = 0.024) in response to supplementary AL. Supplementary AL decreased the population of methanogens (P = 0.001) and tended to decrease that of protozoans (P = 0.097), but increased the populations of F. succinogenes (P < 0.001), R. flavefaciens (P = 0.001), and B. fibrisolvens (P = 0.001).ConclusionsSupplementation of AL at 2.0 g/head·day effectively enhanced OM, N, NDF, and ADF digestibility and reduced daily methane emissions (L/kg BW0.75) in ewes, probably by decreasing the population of ruminal protozoans and methanogens.

Effects of allicin on apoptosis of human rheumatoid arthritis fibroblast-like synoviocytes

Objective To research the effects of allicin on the apoptosis of human rheumatoid arthritis fibroblast-like synoviocytes (RAFLSs).Methods We collected synovial tissues of patients who suffered rheumatoid arthritis and accepted athroplasty operation or excision of synovial tissues with arthroscopy.The standard of diagnosis of RA was the criteria revised by American College of Rheumatology (ACR).We extracted synoviocytes with trypsin and observed the shape of these cells under optical microscopy.The cluster of differentiation 90 (CD90) of RAFLSs was tested by flow cytometry (FCM).The cells were treated with allicin at different concentrations.The apoptosis rate of RAFLSs was tested through DNA fragmentation assay.Results The positive rate of CD90 in the RAFLSs used to the last research was more than 95％.The apoptosis rate of RAFLSs treated with l00 μmol/L allicin was (6.7 ± 1.1)％.As Compared with the control group,there was no statistically significant difference.The apoptosis rate in 200 and 300 μmol/L allicin-treated groups was (12.9 ± 2.1) ％ and (19.7 ± 1.8) ％ respectively.There was significant difference in the apoptosis rate among the three allicin-treated groups.Conclusion Allicin can accelerate apoptosis of RAFLSs in a concentration dependent manner. Key words: Allicin; Rheumatoid arthritis ; Fibroblast-like synoviocyte; Apoptosis

Effects of garlic supplementation on blood pressure

Hypertension is one of the major risk factor for cardiovascular morbidity and mortality. One of primary management of hypertension include dietary changes which could incorporate dietary supplementation ,also use of non pharmacological treatment options is high in patients with high blood pressure .Garlic has played an important dietary as well as medicinal role in human history and it has been on the top ten lists of herbal sales among people. For evaluating the effect of garlic on blood pressure ,we reviewed clinical trials published from 1982 until 2013 by searching in informative bank such as PubMed، Ovid، Elsevier Science , Google Scholar with keywords garlic , blood pressure, hypertension and herbal supplement. The result of this review article showed that several clinical trials have suggested garlic lowers systolic and or diastolic blood pressure and has beneficial effect in controlling hypertension, but negative results also have been obtained in some of trials .Blood pressure reducing properties of garlic have been linked to its hydrogen sulphide production and allicin content , liberated from alliin and the enzyme alliinase. large scale trials are needed to investigate whether standardized garlic preparations could provide a safe alternative or complementary treatment option for hypertension in clinical practice.

In vivo phytotherapy of snail by plant derived active components in control of fascioliasis

Fascioliasis is worldwide zoonotic disease, which caused great economic loss to human being. In vivo killing of Fasciola larva (redia and cercaria) is one of the effective methods to control of fascioliasis. In vivo toxicity of different binary combinations (1:1ratio) of plant derived active components such as citral, ferulic acid, umbelliferone; azadirachtin and allicin were tested against Fasciola larva (redia and cercaria) in snail Lymnaea acuminata . Mortality of larvae were observed at 2h, 4h, 6h and 8h of treatment. In vivo exposure of azadirachtin + allicin (1:1 ratio) was highly toxic against redia and cercaria (8h LC 50 0.007and 0.006 mg/L). Combinations of citral + umbelliferone, cirtal + ferulic acid were less toxicity against redia and cercaria larva than azadirachtin + allicin. In vivo use of these larvicidal active components in the binary combinations at sublethal does will be more helpful in controlling the redia/cercaria than their individual components.

Antiarrhythmic effects and ionic mechanisms of allicin on myocardial injury of diabetic rats induced by streptozotocin

The aim of this study was to evaluate the antiarrhythmic effect of allicin (AL) on streptozotocin (STZ)-induced diabetic rats and explore the possible mechanisms. Hyperglycemia was induced in rats by single intraperitoneal injection of STZ (40 mg/kg). Three days after STZ treatment, the hyperglycemic rats (plasma glucose levels≥16.7 mM) were administered with AL (4, 8, and 16 mg/kg) by intraperitoneal injection daily for 28 days. The fasting blood glucose levels were measured on every seventh day during the 28 days of treatment. The body weight and blood glucose levels were detected after 28 days. Antiarrhythmic effect of AL was observed in the diabetic rats induced by BaCl2. To determine the ionic mechanism in rat ventricular myocytes of AL, action potential duration (APD), L-type calcium current (ICa-L), and inward rectifier potassium current (IK1) were recorded by the whole cell-patch clamp technique. The expressions of L-type calcium channel protein α1C mRNA and cell potassium channels protein Kir2.1 mRNA were studied by RT-PCR. AL normalized the RR interval and QT interval in diabetic rats. AL obviously delayed the onset of ventricular arrhythmia and reduced the score of arrhythmia induced by BaCl2. Electrophysiological experiment revealed that AL could shorten APD through inhibition of ICa-L and enhancement of IK1. RT-PCR analysis indicated that long-term treatment with AL could decrease the expression of α1C mRNA and increase the expression of Kir2.1 mRNA. AL has antiarrhythmic effect in STZ-induced diabetic rats. It is tempting for the application of AL to be a useful therapeutic approach in diabetes with ventricular arrhythmia.

Adjuvant action of garlic sugar solution in animals immunized with Ehrlich ascites tumor cells attenuated with allicin.

Ethanol-insoluble components were extracted from fresh garlic with 0.9% NaCl solution containing streptomycin and penicillin. This extract, containing approximately 10% sugar, 0.3% nitrogen, and 0.4% ash, was termed garlic sugar solution. This garlic sugar solution (Medium 1) was used as the suspending medium for Ehrlich ascites tumor cells attenuated with allicin, the main principle of garlic, and 0.9% NaCl solution containing streptomycin and penicillin (Medium 2) was also used as the suspending medium. Mice of DDD strain were immunized with the attenuated tumor cells suspended in Medium 1 or 2. After immunization, the immunized and control mice were challenged intraperitoneally with viable Ehrlich ascites tumorcells. Animals immunized with the attenuated tumor cells suspended in Medium 1 acquired significantly stronger resistance against the tumor cells than animals immunized with those suspended in Medium 2.

Allicin protects against myocardial apoptosis and fibrosis in streptozotocin-induced diabetic rats

To evaluate the cardioprotective effect of allicin (AL) on myocardial injury of streptozotocin (STZ)-induced diabetic rats and to further explore its underlying mechanisms. Hyperglycemia was induced in rats by single intraperitoneal injection of STZ (40mg/kg). Three days after STZ induction, the hyperglycemic rats (plasma glucose levels ≥16.7mmol/l) were treated with AL by intraperitoneal injection at the doses of 4mg/kg, 8mg/kg, and 16mg/kg daily for 28days. The fasting blood glucose levels were measured on every 7th day during the 28days of treatment. The body weight, blood glucose, and parameter of cardiac function were detected after 4weeks to study the cardioprotective effects of AL on diabetic rats in vivo. The apoptotic index of cardiomyocytes was estimated by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The expressions of Fas, Bcl-2, CTGF, and TGF-β1 protein were studied by immunohistochemistry. Laser scanning confocal microscopy technique was utilized to observe the effects of AL on intracellular calcium concentration ([Ca2+]i) in rat ventricular cardiomyocytes. AL at the doses of 4mg/kg, 8mg/kg, and 16mg/kg significantly reduced blood glucose levels in a dose-dependent manner and increased body weight as well compared with the model group. Hemodynamic parameters including left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), and maximum rate of left ventricular pressure rise and fall (+dp/dtmax and −dp/dtmax) were significantly restored back to normal levels in AL-treated (8mg/kg and 16mg/kg) rats compared with diabetic model rats. AL markedly inhibited cardiomyocyte apoptosis induced by diabetic cardiac injury. Further investigation revealed that this inhibitory effect on cell apoptosis was mediated by increasing anti-apoptotic protein Bcl-2 and decreasing pro-apoptotic protein Fas. Additional experiments demonstrated AL abrogated myocardial fibrosis by blocking the expressions of CTGF and TGF-β1 protein. AL shows protective action on myocardial injury in diabetic rats. The possible mechanisms were involved in reducing blood glucose, correcting hemodynamic impairment, reducing Fas expression, activating Bcl-2 expression, decreasing intracellular calcium overload, inhibiting the expressions of TGF-β1 and CTGF, and further improving cardiac function.

Garlic (Allium sativum L.): A review of potential therapeutic applications

Garlic (Allium sativum L. fam. Alliaceae), one of the best‑researched herbal remedies, is frequently used as a food and a spice. Garlic contains enzymes (e.g., allinase), sulphur‑containing compounds, including alliin, and compounds produced enzymatically from alliin (for example, allicin). Conventionally, it has been used to treat infections, wounds, diarrhoea, rheumatism, heart disease, diabetes and many other disorders. Experimental studies have demonstrated that garlic exhibits antibacterial, antihypertensive, cardioprotective, antilipidaemic, anticarcinogenic, immunostimulant and hypoglycaemic properties. Clinically, garlic has been investigated for a variety of indications, namely, hypertension, hypercholesterolaemia, diabetes and for the prevention of arteriosclerosis and cancer. Systematic reviews are available for the possible antilipidaemic, antihypertensive, antithrombotic and chemopreventive effects. Garlic appears to be generally safe although allergic reactions may occur. Key words: Allium sativum, anticarcinogenic, antimicrobial, antioxidant, cardioprotective, garlic

In vitro inhibitory effect of diallyl sulfide on cell proliferation and vascular endothelial growth factor expression of human osteosarcoma MG-63 cells

Objective To investigate the effect of diallyl sulfide (DAS) on the growth and vascular endothelial growth factor (VEGF) expression of human MG63 cells in vitro, and to explore the curative possibility of osteosarcoma with DAS. Methods The effect of DAS at the concentrations of 0, 10, 20, 40 g/L on growth and proliferation was assessed by methylthiazol tetrazolium (MTT) assay. The morphology of the cells was examined under the inverted phase contrast microscopy and Hoechst 33258 fluorescent staining. The apoptosis was detected by annexin-V/PI double-labeled cytometry after treated with DAS at different concentrations of 0, 10, 20, 40 g/L for 48 h. The effect of DAS on the cell cycle of MG63 cells was studied by flow cytometry. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were used to analyze the changes of VEGF mRNA and protein levels. Results Proliferation of MG63cells was significantly inhibited by DAS in a time- and dose-dependent fashion. As compared with the control group, the DAS over the concentration of 10 g/L significantly inhibited the proliferation of MG63 cells (P＜0.05). MG63 cells grew round and small obviously after being treated with DAS under the inverted microscopy. The apoptotic rate was(4.7±1.4)%, (18.6±0.7)%, (24.9±1.1)% after the cells were treated with DAS at the concentrations of 10, 20, 40 g/L for 48 h, respectively, which was significantly different from that in the control group (1.70±0.36)%, P＜0.05. Allicin reduced the secretion of VEGF and inhibited the level of VEGF mRNA expression in a dose-dependent manner. Conclusion DAS can inhibit the proliferation of MG63 cells in vitro. The antitumor effects of allicin may be related to down-regulation of the expression of VEGF mRNA. Key words: Osteosarcoma; DAS; Proliferation; VEGF

The effects of allicin on expression of PDCD5 in human retinoblastoma cells

目的 探讨大蒜素对人视网膜母细胞瘤(Rb)细胞的抑制作用及其对程序化细胞死亡因子5(PDCD5)表达的影响.方法 分别用不同质量浓度的大蒜素、顺铂及大蒜素和顺铂联合处理人Rb细胞,在作用24、48、72 h后观察Rb细胞的形态,并应用免疫细胞化学法检测不同处理条件下各时间点PDCD5的表达情况.结果 人Rb细胞在不同质量浓度大蒜素、顺铂以及大蒜素和顺铂联合作用下,细胞生长受到抑制.不同质量浓度的大蒜素均可以上调人Rb细胞中PDCD5的表达.与对照组比较差异均有统计学意义(P<0.05).随着大蒜素作用时间的延长,PDCD5的表达依次上升.大蒜素(15μg/mL)和顺铂(3μg/mL)联合用药可增强对人Rb细胞的生长抑制,与单独用药比较,上调PDCD5表达的作用差异有统计学意义(P<0.05).结论 Rb细胞中存在与细胞凋亡有关的PDCD5蛋白低表达.大蒜素可抑制人Rb细胞的生长,且抑制作用具有时间和质量浓度依赖性.大蒜素和顺铂联合用药作用强于单独用药,可提高药物对肿瘤细胞的生长抑制。

Experiment research of anti-tumor effect of allicin for murine bladder cancer

目的 探讨大蒜素对小鼠膀胱癌的抗肿瘤效果和机制.方法将100μg/ml大蒜素直接加入肿瘤细胞培养6 h,用相差显微镜观察肿瘤细胞形态学变化.MTT法测定大蒜素对肿瘤细胞体外生长的直接影响.动物实验检测大蒜素的抗癌效果.在实验第19天切除肿瘤组织作病理学检查,了解免疫反应情况.LDH释放法测大蒜素注射后淋巴细胞对肿瘤细胞的细胞毒活性.结果大蒜素对膀胱肿瘤细胞有明显的直接细胞毒作用,与生理盐水对照组相比,大蒜素剂量为0.1 mg/ml时,肿瘤的抑制率可达56%,剂量为2.5mg/ml时,肿瘤抑制率可达99%.LDH释放法测得大蒜素注射后,能产生针对肿瘤细胞的细胞毒淋巴细胞.结论大蒜素对膀胱肿瘤有明显的抑制作用。

Effect of Garlic Oil and Four of its Compounds on Rumen Microbial Fermentation

Different concentrations (3, 30, 300, and 3000mg/L of culture fluid) of garlic oil (GAR), diallyl sulfide (DAS), diallyl disulfide (DAD), allicin (ALL), and allyl mercaptan (ALM) were incubated for 24h in diluted ruminal fluid with a 50:50 forage:concentrate diet (17.7% crude protein; 30.7% neutral detergent fiber) to evaluate their effects on rumen microbial fermentation. Garlic oil (30 and 300mg/L), DAD (30 and 300mg/L), and ALM (300mg/L) resulted in lower molar proportion of acetate and higher proportions of propionate and butyrate. In contrast, at 300mg/L, DAS only increased the proportion of butyrate, and ALL had no effects on volatile fatty acid proportions. In a dual-flow continuous culture of rumen fluid fed the same 50:50 forage:concentrate diet, addition of GAR (312mg/L), DAD (31.2 and 312mg/L), and ALM (31.2 and 312mg/L) resulted in similar changes to those observed in batch culture, with the exception of the lack of effect of DAD on the proportion of propionate. In a third in vitro study, the potential of GAR (300mg/L), DAD (300mg/L), and ALM (300mg/L) to decrease methane production was evaluated. Treatments GAR, DAD, and ALM resulted in a decrease in methane production of 73.6, 68.5, and 19.5%, respectively, compared with the control. These results confirm the ability of GAR, DAD, and ALM to decrease methane production, which may help to improve the efficiency of energy use in the rumen.