Allicin as add-on therapy for Helicobacter pylori infection: A systematic review and meta-analysis.

BACKGROUND: Allicin (2-propene-1-sulfinothioic acid S-2-propenyl ester, diallyl thiosulfinate) extracted from garlic, has proven activity against Helicobacter pylori (H. Pylori) infection. In recent years, clinical trials have explored its utility as an add-on therapy with variable outcomes reported. AIM: To perform a systemic review of allicin as an add-on treatment for H. Pylori infection and assess its efficacy in randomized controlled trials (RCTs). METHODS: Electronic databases including MEDLINE, EMBASE, the Web of Science, the Cochrane Database, the China National Knowledge Infrastructure Database, Chinese VIP Information Databases, Chinese Medical Databases, and the Wan-Fang Database were searched for keywords including "allicin", "Helicobacter pylori", "randomized clinical trials", and their synonyms. A meta-analysis was performed using the fixed-effects model for low heterogeneity and the random-effects model for high heterogeneity with sensitivity analysis. Bias was evaluated using Egger's tests. Trial sequential analysis (TSA) was used to evaluate information size and treatment benefits. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) was used to assess the level of quality, and studies were classed as "high quality", "moderate quality", "low quality", and "very low quality". RESULTS: A total of eight RCTs consisting of 867 participants (435 from the allicin group and 432 from the control group) were included. Eradication rate in the allicin group (93.33%, 406/435) was significantly higher than that of the control group (83.56%, 361/432) [I 2 = 0%, odds ratio (OR) = 2.75, 95% confidence interval (CI): 1.74-4.35, P < 0.001]. The healing rate of ulcers following H. pylori therapy in the allicin group (86.17%, 349/405) was significantly higher than that of the control group (75.87%, 305/402) [I 2 = 0%, OR = 2.05, 95%CI: 1.39-3.03, P < 0.001]. The total remission rate of peptic ulcers across all allicin groups was 97.16%, which was significantly higher than that of controls [96.05% (389/405) vs 86.55% (360/402), I 2 = 0, OR = 3.04, 95%CI: 1.51-6.12, P = 0.015]. No significant differences in side effects were observed. TSA suggested that the trials were of sufficient standard to draw reliable conclusions. The quality of outcomes including eradication rates and side effects was graded as "very low" due to downgrades for "risk of bias" and "indirectness". Other outcomes such as ulcer healing rates and total ulcer remission rates were graded as "low" due to downgrades for "risk of bias". CONCLUSION: Allicin as an add-on therapy improves H. pylori eradication, healing of ulcers, and remission of symptoms. These results are suggested to be treated with caution due to limited quality.

Downregulating PI3K/Akt/NF-κB signaling with allicin for ameliorating the progression of osteoarthritis: in vitro and vivo studies.

Osteoarthritis (OA) is characterized by the degeneration and destruction of articular cartilage. Allicin, a dietary garlic active constituent, exerts anti-inflammatory effects on several diseases. However, its effects on OA have not been clearly elucidated. In this study, we explored the effects of allicin on OA in both in vitro and in vivo models. Allicin inhibited interleukin-1ß (IL-1ß) induced overproduction of nitric oxide, inducible nitric oxide synthase, prostaglandin E2, and cyclooxygenase-2, as well as pro-inflammatory cytokines tumor necrosis factor alpha and interleukin-6 in chondrocytes in a dose-dependent manner. Meanwhile, allicin reversed the overproduction of metalloproteinase-13 and a disintegrin and metalloproteinase with thrombospondin motifs-5 and the decrease of aggrecan and type II collagen. Furthermore, allicin dramatically suppressed IL-1ß-stimulated PI3K/Akt/NF-κB activation in chondrocytes. In vivo, treatment with allicin prevented the destruction of cartilage and inhibited PI3K/Akt/NF-κB activation in the cartilage of mice OA models. Taken together, these results indicate that allicin may be a potential therapeutic agent for OA.

The role of diallyl thiosulfinate associated with nuciferine and diosgenin in the treatment of premature ejaculation: A pilot study.

OBJECTIVE: To assess the efficacy and safety of an association of diallyl thiosulfinate with nuciferine and diosgenin in the treatment of a group of patients suffering from premature ejaculation (PE), primary or secondary to erectile dysfunction (ED). MATERIALS AND METHODS: From July 2015 to October 2016, 143 patients (mean age 25.3; range 18-39) affected by PE completed the study and were finally analyzed in this phase I study. All patients, after clinical assessment and laboratory evaluation were asked to take an association of diallyl thiosulfinate with nuciferine and diosgenin as oral tablet, once a day, on alternate days, for three months. At the baseline and after three months of treatment, each patient was asked to complete the following questionnaires: International Index of Erectile Function (IIEF-5), Premature Ejaculation Diagnostic Tool (PEDT), Male Sexual Health Questionnaire (MSHQ). RESULTS: A statistical significant improvement in terms of erectile function, comparing the IIEF-5 value at baseline and follow- up visit was found (respectively IIEF-5: 8.7 vs 14.01; p < 0.001). Moreover, at follow-up visit, 97/143 men (67.8%) referred a subjective improvement of the erection quality and a better control of the ejaculation (PROs). The IELT improved too between the baseline evaluation and the follow-up visit (p < 0.001). CONCLUSION: In conclusion, our study, even if supported by preliminary results, showed how Diallyl Thiosulfinate, Nuciferine and Diosgenin is able to improve the control of ejaculation in patients suffering from PE, primary or secondary to ED without any significant adverse effects.

The Beneficial Effects of Allicin in Chronic Kidney Disease Are Comparable to Losartan.

Recent studies suggest that allicin may play a role in chronic kidney disease (CKD), reducing hypertension and oxidative stress and improving renal dysfunction. In the present study, CKD was induced by 5/6 nephrectomy and the animals were divided into four treatment groups as follows: control (C), CKD, CKD+allicin (40 mg/kg pathway oral) (CKDA), and CKD+Losartan (20 mg/kg) (CKDL). After CKD induction, the rats developed hypertension from week 3 to the end of the study. This was associated with increased creatinine and blood urea nitrogen (BUN) levels in serum, increased albuminuria, increased urinary excretion of N-acetyl-ß-d-glucosaminidase (NAG), increased nephrin expression, and incrased histological alterations in the cortex. The levels of angiotensin receptors and endothelial nitric oxide synthase (eNOS) were decreased in the renal cortex from the CKD group. Otherwise, lipid and protein oxidation were higher in the CKD group than in the control group. A disturbance was observed in the expression levels of the nuclear factor erythroid 2-related factor 2/Kelch ECH associating protein 1 system (Nrf2/keap1) and the antioxidant enzymes catalase, superoxide dismutase, and heme oxygenase-1. Allicin or losartan treatments relieved renal dysfunction, hypertension, and oxidative stress. In addition, both treatments showed the same efficacy on the expression of angiotensin receptors, the nephrin, Nrf2/keap1 pathway, and eNOS. Further in silico analyses suggest that allicin and losartan could have a common mechanism involving interaction with AT1 receptors. Allicin showed antihypertensive, antioxidant, and nephroprotective effects. The beneficial effects showed by allicin are similar, or even better, than those of losartan. In fact, the effect of allicin on blood pressure and renal function is comparable to reductions seen with losartan, a prescription drug commonly used as a first-line therapy.

Therapeutic Hotline. Oral allicin in the treatment of Behcet's disease through attenuating oxidative stress: A pilot study in 20 patients with mucocutaneous lesions.

Behçet's disease (BD) involves oxidative stress (OS) aggression and imbalanced oxidant/antioxidant status. Owing to its antioxidant property, allicin is proposed for treating BD. In this study, we aimed to investigate the efficacy and safety of allicin on patients with BD with mucocutaneous involvement. Twenty patients with active BD were treated with allicin for 12 weeks and followed up to 16 weeks. A clinical manifestations index and scoring system was the primary technique for efficacy evaluation at baseline and Week 4, 12, 16. The secondary efficacy variables were OS-related biomarkers determined at first and final visit. Side effects were assessed at each visit. By the end of study, 18 patients completed the trail. Allicin was effective in decreasing ulcer and cutaneous parameters (p < .05). Especially, the greatest reduction of mucocutaneous scores emerged from baseline after the first four-week treatment (p < .05). Meanwhile, allicin remarkably ameliorated OS-related parameters. Besides, some side effects were observed on allicin, these adverse reactions, however, disappeared upon cessation of drugs. In conclusion, allicin is a safe and effective treatment for BD, which may be associated with its inhibiting OS and regulating oxidant/antioxidant status balance.

Effects of allicin on cardiovascular risk factors in spontaneously hypertensive rats.

BACKGROUND: Allium sativum, the active ingredient in garlic, is known to have a beneficial effect on major cardiovascular risk factors, including dyslipidemia, blood pressure, blood glucose and insulin levels. However, the data on the significance of these effects are inconsistent due to methodological limitations, especially the use of whole garlic cloves which does not allow controlled dosing of the active compound. OBJECTIVES: To study the effects of purified allicin on the cardiovascular system. METHODS: Spontaneously hypertensive rats treated for 6 weeks with a daily dose of 80 mg/kg/day of purified allicin added to their chow were compared to control rats that were fed regular chow. Weight, systolic blood pressure (SBP), triglycerides, cholesterol, insulin and adiponectin were measured at baseline and at the end of the study. RESULTS: Allicin had no effect on body weight whereas it reduced SBP significantly from 190 +/- 7.5 mmHg to 168 +/- 5.7 (P < 0.0001) and triglyceride levels from 96 +/- 25 mg/dl to 71 +/- 19 (P = 0.009). Allicin had no effect on plasma cholesterol, insulin and adiponectin levels. CONCLUSIONS: Allicin lowered blood pressure and triglyceride levels in spontaneously hypertensive rats. This effect was not mediated through weight loss.

Healthy and adverse effects of plant-derived functional metabolites: the need of revealing their content and bioactivity in a complex food matrix.

In recent years, both food quality and its effect on human health have become a fundamental issue all over the world. As a consequence of this new and increased awareness, American, European, and Asian policymakers have strongly encouraged the research programs on food quality and safety thematic. Attempts to improve human health and to satisfy people's desire for healthcare without intake of pharmaceuticals, has led the food industry to focus attention on functional or nutraceutical food. For a long time, compounds with nutraceutical activity have been produced chemically, but the new demands for a sustainable life have gradually led the food industry to move towards natural compounds, mainly those derived from plants. Many phytochemicals are known to promote good health, but, sometimes, undesirable effects are also reported. Furthermore, several products present on the market show few benefits and sometimes even the reverse - unhealthy effects; the evidence of efficacy is often unconvincing and epidemiological studies are necessary to prove the truth of their claims. Therefore, there is a need for reliable analytical control systems to measure the bioactivity, content, and quality of these additives in the complex food matrix. This review describes the most widespread nutraceutics and an analytical control of the same using recently developed biosensors which are promising candidates for routine control of functional foods.

Garlic for the common cold.

BACKGROUND: Garlic is alleged to have antimicrobial and antiviral properties that relieve the common cold, among other beneficial effects. There is widespread usage of garlic supplements. The common cold is associated with significant morbidity and economic consequences. On average, children have six to eight colds per year and adults have two to four. OBJECTIVES: To determine whether garlic (allium sativum) is effective for either the prevention or treatment of the common cold, when compared to placebo, no treatment or other treatments. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2011, Issue 4), which includes the Cochrane Acute Respiratory Infections Group Specialised Register, OLDMEDLINE (1950 to 1965), MEDLINE (January 1966 to November week 3, 2011), EMBASE (1974 to December 2011) and AMED (1985 to December 2011). SELECTION CRITERIA: Randomised controlled trials of common cold prevention and treatment comparing garlic with placebo, no treatment or standard treatment. DATA COLLECTION AND ANALYSIS: Two review authors independently reviewed and selected trials from searches, assessed and rated study quality and extracted relevant data. MAIN RESULTS: Of the six trials identified as potentially relevant from our searches, only one trial met the inclusion criteria. This trial randomly assigned 146 participants to either a garlic supplement (with 180 mg of allicin content) or a placebo (once daily) for 12 weeks. The trial reported 24 occurrences of the common cold in the garlic intervention group compared with 65 in the placebo group (P < 0.001), resulting in fewer days of illness in the garlic group compared with the placebo group (111 versus 366). The number of days to recovery from an occurrence of the common cold was similar in both groups (4.63 versus 5.63). Only one trial met the inclusion criteria, therefore limited conclusions can be drawn. The trial relied on self reported episodes of the common cold but was of reasonable quality in terms of randomisation and allocation concealment. Adverse effects included rash and odour. AUTHORS' CONCLUSIONS: There is insufficient clinical trial evidence regarding the effects of garlic in preventing or treating the common cold. A single trial suggested that garlic may prevent occurrences of the common cold but more studies are needed to validate this finding. Claims of effectiveness appear to rely largely on poor-quality evidence.

Effects of (2R)-(3-amino-2-fluoropropyl)sulphinic acid (AFPSiA) on transient lower oesophageal sphincter relaxation in dogs and mechanism of hypothermic effects in mice.

The effects of the novel GABA analogue (2R)-(3-amino-2-fluoropropyl)sulphinic acid (AFPSiA) on transient lower oesophageal sphincter relaxations (TLOSRs) were studied in the dog. In addition, the GABA(A)/GABA(B) selectivity was determined in vitro and in vivo, and the pharmacokinetics and the metabolism of the compound were studied in the dog and rat. TLOSRs were reduced by 55 +/- 8% after intragastric administration of AFPSiA at 14 mumol kg(-1) and did not decrease further at higher doses. When evaluated 2 and 4 h after administration, the effect declined to 37 +/- 6 and 16 +/- 9%, respectively. Spontaneous swallowing was only significantly inhibited at 100 micromol kg(-1). The oral availability of AFPSiA was 52 +/- 17 and 71 +/- 4% in the dog and rat, respectively. A fraction of AFPSiA was oxidised to the corresponding sulphonate, (2R)-(3-amino-2-fluoropropyl)sulphonic acid (AFPSoA) after oral administration to the rat and dog. In rat brain membranes, AFPSiA was found to have ten times higher affinity for rat brain GABA(B) (K(i) =47 +/- 4.4 nM) compared to GABA(A) (K(i) = 430 +/- 46 nM) binding sites. The compound was a full agonist at human recombinant GABA(B(1a,2)) receptors (EC(50) = 130 +/- 10 nM). In contrast, the metabolite AFPSoA was considerably more selective for binding to rat brain GABA(A) (K(i) = 37 +/- 3.1 nM) vs GABA(B) (K(i) = 6800 +/- 280 nM) receptors. In the mouse, high doses (1-8 mmol kg(-1)) of AFPSiA induced a rapid and mild hypothermia followed by a profound and sustained hypothermia at the higher doses tested (6 and 8 mmol kg(-1)). This effect was unaffected by the selective GABA(B) receptor antagonist CGP62349. AFPSoA (1 and 2 mmol kg(-1)) produced transient and moderate hypothermia while the hypothermic response was considerably larger at 4 mmol kg(-1).It is concluded that AFPSiA inhibits but does not abolish TLOSRs in the dog. High doses of the compound induce hypothermia in the mouse, which probably is attributable to activation of the GABA(A) receptor. The latter effect may be caused both by AFPSiA and its oxidised sulphonic acid metabolite AFPSoA.

A comparative study on hypocholesterolaemic effect of allicin, whole germinated seeds of bengal gram and guggulipid of gum gugglu.

The daily use of allicin and whole germinated bengal gram seeds for 8 weeks led to a significant decrease in serum cholesterol levels in normal volunteers with no side effects. The standard reference, guggulipid therapy, significantly (p < 0.001) reduced the mean serum cholesterol level to 142.88 +/- 24.14 mg/100 mL from an initial status of 211.91 +/- 6.23 mg/100mL (32.36% +/- 12.48% fall). Allicin treatment significantly reduced the mean serum cholesterol level to 129.99 +/- 2.79 mg/100 mL from a pre-treatment value of 148.10 +/- 8. 81 mg/100mL, a fall of 13.36% +/- 4.64%. The serum cholesterol value was reduced to 135.62+/- 22.85 mg/100 mL from a pre-treatment value of 157.29 +/- 4.94 mg/100mL (17.15% +/- 9.94% fall) due to daily use of whole germinated bengal gram seeds. Hence the hypocholesterolaemic effects of allicin and whole germinated bengal gram seeds are comparable to the established standard reference, guggulipid. These two materials are herbal in origin and it is supposed to have a lesser risk-benefit ratio compared with other available synthetic drugs. The inclusion of these herbal products in the normal diet may be an alternative effective measure for hypercholesterolaemia.

Health effects associated with sulfuryl fluoride and methyl bromide exposure among structural fumigation workers.

OBJECTIVES: This study assessed the health effects associated with occupational exposure to methyl bromide and sulfuryl fluoride among structural fumigation workers. METHODS: A cross-sectional study of 123 structural fumigation workers and 120 referents in south Florida was conducted. Nerve conduction, vibration, neurobehavioral, visual, olfactory, and renal function testing was included. RESULTS: The median lifetime duration of methyl bromide and sulfuryl fluoride exposure among workers was 1.20 years and 2.85 years, respectively. Sulfuryl fluoride exposure over the year preceding examination was associated with significantly reduced performance on the Pattern Memory Test and on olfactory testing. In addition, fumigation workers had significantly reduced performance on the Santa Ana Dexterity Test of the dominant hand and a nonsignificantly higher prevalence of carpal tunnel syndrome than did the referents. CONCLUSIONS: Occupational sulfuryl fluoride exposures may be associated with subclinical effects on the central nervous system, including effects on olfactory and some cognitive functions. However, no widespread pattern of cognitive deficits was observed. The peripheral nerve effects were likely caused by ergonomic stresses experienced by the fumigation workers.

Agreement between company-recorded and self-reported estimates of duration and frequency of occupational fumigant exposure.

Investigators must often rely on self-reported work history information collected with questionnaires. However, little is known about the agreement between self-reported estimates of exposure and records kept by companies. As part of a cross-sectional medical study of structural fumigation workers, self-reported work history information was collected on both duration and frequency of exposure using an interviewer-administered questionnaire. All company records available on these workers were also collected. Only 15 of 81 structural fumigation companies identified by study participants as current or past structural fumigation employers had records suitable for comparison. These 15 companies employed 32 of the workers who participated in the cross-sectional medical study. The exposure information provided by the 32 workers was compared to information obtained from company records. By examining the agreement between these two data sources, potential limitations were identified in both the self-reported and company-recorded exposure data. By recognizing these limitations in the exposure data, we identified the most appropriate exposure measures to be used in subsequent data analyses. This exercise also demonstrated the difficulties in undertaking these exposure comparisons in an industry consisting of many small, independent companies. Similar difficulties with assessing exposures may be experienced by investigators studying other service industries consisting of many small, independent companies (e.g., dry cleaning, auto repair).

Garlic for cryptosporidiosis?

AIDS: The AIDS Research Alliance in California has been testing the effectiveness of garlic in combating cryptosporidiosis, a parasitic infection of the intestinal tract. The test involved patients taking liquid Allicin mixed with distilled water twice daily. Side effects included the expected garlic taste and smell, but patients suffered from less diarrhea and had stable or increasing body weight. For several patients, repeated testing showed negative results for cryptosporidium parasites. Larger trials are planned.^ieng

Possible nutritional factors in induced pemphigus.

Today it is generally accepted that every drug that possesses an active thiol group in its molecule is capable of inducing pemphigus. Some plants, in particular those belonging to the Allium group, contain several active compounds with stable disulfide and thiol groups in their molecule. The Allium group contains many important vegetables like onion, leek and garlic. Examples of molecules with an active thiol group are: CH2 = CH-CH2-S-S-CH2-CH = CH2 (diallyl disulfide) or CH2 = CH-CH2-S(O)S-CH2-CH = CH2 (allicin). It is suggested that some foods, in particular vegetables of the Allium group that contain active thiol groups in their molecule, could contribute to the induction of pemphigus. In general, nutritional factors should be added to the list of exogenous factors that are capable of inducing pemphigus.