Effects of garlic on platelet biochemistry and physiology

Preclinical Evaluation of the Anticoagulant Effect of an Aqueous Extract of Snow Mountain Garlic

Background/Objectives: In the genus Allium, it has been shown that some organosulfate compounds of common garlic and onion have an antiplatelet effect. Still, little is known about the anticoagulant activity of the species, Allium ampeloprasum L., specifically Snow mountain garlic; due to its growth site at 6000 m above sea level at temperatures of -10 °C, it could contain different organosulfate compounds. Methods: This study evaluated the anticoagulant effect of a lyophilized aqueous extract of S. mountain garlic in vivo, toxicity in male Wistar rats for 90 days, and the organosulfate compounds present. Results: There was a significant increase (p < 0.05) in the area under the curve for bleeding time at doses of 500 and 1000 mg/kg/d of lyophilized aqueous extract of Snow mountain garlic and 100 mg/kg/d of acetylsalicylic acid. The ED50 was 366 ± 2.43 mg/kg. For chronic toxicity in vivo, no histopathological alterations were found at doses below 500 mg/kg. On the other hand, organosulfate compounds were found in the lyophilized aqueous extract of S. mountain garlic that had not been documented to have an anticoagulant effect. Conclusions: We conclude that S. mountain garlic contains anticoagulant compounds which may be candidates for the treatment of thrombosis.

Randomized, double-blind clinical trial evaluating the impact of freeze-dried garlic extract capsules on blood pressure, lipid profile, and nitric oxide levels in individuals at risk for hypertension

OBJECTIVES

Hypertension, substantially heightens the risk of cardiovascular disease. This study aims to evaluate the effectiveness of freeze-dried garlic extract in blood pressure and lipid profiles in prehypertensive individuals.

METHODS

Participants (age of 30-70 years) were allocated to intervention (n=47) or control (n=49) groups. The intervention group received two capsules of freeze-dried garlic extract daily for eight weeks, while the control group received identical placebo capsules. Primary outcomes, SBP, DBP, PP, MAP, TC, TG, LDL and HDL levels, serum NO levels, were assessed at baseline, four weeks, and eight weeks.

RESULTS

At the end of study, results showed significant changes in the values of SBP, DBP, and MAP except for PP. In comparison to those who received the placebo, a significant drop in SBP, DBP (p<0.001), and MAP (p<0.001) was observed in the intervention group. Also, there were significant changes in TG, LDL, TC, and HDL levels in the interventional group. A noticeable decline was reported in TG (p<0.001), LDL (p<0.001), and TC (p<0.001), while HDL levels increased (p<0.001) in the intervention group compared to those receiving the placebo. Following garlic supplementation, a significant increase in blood NO levels was reported in the intervention group (p<0.001).

CONCLUSIONS

The study showed that garlic supplementation was effective in lowering blood pressure, improving lipid profile, and increasing nitric oxide levels in prehypertensive participants. These results indicate that garlic could be a valuable complementary therapy for managing prehypertension.

Characterizations of White Mulberry, Sea-Buckthorn, Garlic, Lily of the Valley, Motherwort, and Hawthorn as Potential Candidates for Managing Cardiovascular Disease-In Vitro and Ex Vivo Animal Studies

Cardiovascular diseases are a broadly understood concept focusing on vascular and heart dysfunction. Lack of physical exercise, type 2 diabetes, obesity, hypertension, dyslipidemia, thromboembolism, and kidney and lung diseases all contribute to the development of heart and blood vessel dysfunction. Although effective and important, traditional treatment with diuretics, statins, beta blockers, calcium inhibitors, ACE inhibitors, and anti-platelet drugs remains a second-line treatment after dietary interventions and lifestyle changes. Scientists worldwide are still looking for an herbal product that would be effective and free from side effects, either taken together with or before the standard pharmacological intervention. Such herbal-originated medication therapy may include Morus alba L. (white mulberry), Elaeagnus rhamnoides (L.) A. Nelson (sea-buckthorn), Allium sativum L. (garlic), Convallaria majalis L. (lily of the valley), Leonurus cardiaca L. (motherwort), and Crataegus spp. (hawthorn). Valuable herbal raw materials include leaves, fruits, seeds, and even thorns. This short review focuses on six herbs that can constitute an interesting and potential therapeutic option in the management of cardiovascular disorders.

Effect of garlic extract on markers of lipid metabolism and inflammation in coronary artery disease (CAD) patients: A systematic review and meta-analysis

Several preclinical studies have focused on the beneficial effects of garlic on cardiovascular diseases, but the results were inconsistent. We performed a systematic review and meta-analysis on the effect of garlic powder tablets and aged garlic extract (AGE) in CAD patients, mainly focusing on blood pressure, coronary artery calcification, lipid profile, and inflammatory markers. We searched PubMed, Cochrane CENTRAL, and Google Scholar to identify randomized controlled trials which examined garlic's effect on CAD patients. The standardized mean difference with 95% CI was calculated using fixed-effect or random-effect models. Garlic has shown statistically significant changes of HDL (SMD = 0.18; 95% CI = -0.00 to 0.37; p = .05); LDL (SMD = -0.27; 95% CI = -0.46 to -0.08; p = .004), apolipoprotein-A (SMD = 0.68; 95% CI = 0.24 1.13; p = .002), C-RP (SMD = -0.59; 95% CI = -0.92 to -0.25; p = .0007), IL-6 (SMD = -1.08; 95% CI = -2.17 to 0.01; p = .05), homocysteine (SMD = -0.66; 95% CI = -1.04 to -0.28; p = .0007) and CAC score (SMD = -1.61; 95% CI = -2.66 to -0.57; p = .003). In the case of subgroup analysis, the overall effect was significantly effective in reducing TC, LDL levels and improving HDL levels in CV risk patients. Our study findings provide consistent evidence that intake of garlic reduces CVD risk factors. However, garlic could be considered a safe natural medicine to debilitate inflammation in CAD patients.

Platelet Aggregation Inhibition: An Evidence-Based Systematic Review on the Role of Herbs for Primary Prevention Based on Randomized Controlled Trials

BACKGROUND

Platelet aggregation is a crucial mechanism in the progression of atherothrombotic events. This systematic review aims to introduce the plants studied in healthy people as the primary prevention to inhibit platelet aggregation. We also discuss possible mechanisms that are involved in the inhibition of platelet aggregation.

METHODS

A systematic search on the electronic medical databases from 1970 to February 2020 was performed. The selected keywords were: "herb", "plant", "platelet aggregation", "platelet activation", "clinical trial", "randomized" and "controlled".

RESULTS

The result of the initial search was a pool of 136 articles. After initial abstract reviewing, there were 55 relevant articles. Finally, 28 eligible records fulfilled our inclusion criteria to enter the qualitative synthesis process.

CONCLUSION

Out of the 10 plants evaluated in the clinical trials, nine had inhibitory effects on platelet aggregation. Most of the reviewed plants, including tomato (Solanum lycopersicum L), garlic (Allium sativum), kiwifruit (Actinidia deliciosa), cacao (Theobroma cacao), grape (Vitis vinifera), ginkgo (Ginkgo biloba), flaxseed (Linum usitatissimum), sea buckthorn berry (Hippophae), and argan (Argania spinose) could be potential sources for the primary prevention of atherothrombotic events at an appropriate dosage. Finally, we do not consider phytoceuticals as a replacement for the guideline-directed medical treatment. Large randomized double-blind clinical trials are required to evaluate the anti-platelet characteristics of these plants for the adjuvant primary prevention of cardiovascular disease.

A systematic review of randomized controlled trials related to the effects of garlic supplementation on platelet aggregation

The increment of platelet aggregation factors has been considered a key phenomenon in atherosclerosis. Studies have shown that garlic (Allium sativum) is associated with a reduction in platelet aggregation and thrombosis. Hence, the present systematic review was conducted to evaluate the effect of garlic on platelet aggregation. All randomized controlled trials (RCTs) with keywords related to garlic and platelet aggregation were thoroughly searched in electronic databases including PubMed, Scopus, ISI Web of Science, and Google Scholar up to January 2021. Moreover, the references of all related articles were screened to discover more relevant studies. The quality of each study was reported based on Cochrane Collaboration's tool. In total, 12 studies met the inclusion criteria from 18,235 identified articles (including 595 participants). Most of the studies assessed platelet aggregation in response to different inducers. Of the 12 clinical trials, six studies depicted the beneficial effect of garlic on reducing platelet aggregation. The summary of the quality assessment indicated that most of the studies had high-quality scores. Regarding the small number of RCTs and heterogeneity between studies, it is impossible to make a proper conclusion about the impacts of garlic on platelet aggregation. Therefore, further precise trials with a standard design are necessary to validate the anti-thrombotic effect of garlic.

S-Allyl cysteine in garlic (Allium sativum): Formation, biofunction, and resistance to food processing for value-added product development

S-allyl cysteine (SAC), which is the most abundant bioactive compound in black garlic (BG; Allium sativum), has been shown to have antioxidant, anti-apoptotic, anti-inflammatory, anti-obesity, cardioprotective, neuroprotective, and hepatoprotective activities. Sulfur compounds are the most distinctive bioactive elements in garlic. Previous studies have provided evidence that the concentration of SAC in fresh garlic is in the range of 19.0-1736.3 μg/g. Meanwhile, for processed garlic, such as frozen and thawed garlic, pickled garlic, fermented garlic extract, and BG, the SAC content increased to up to 8021.2 μg/g. BG is an SAC-containing product, with heat treatment being used in nearly all methods of BG production. Therefore, strategies to increase the SAC level in garlic are of great interest; however, further knowledge is required about the effect of processing factors and mechanistic changes. This review explains the formation of SAC in garlic, introduces its biological effects, and summarizes the recent advances in processing methods that can affect SAC levels in garlic, including heat treatment, enzymatic treatment, freezing, fermentation, ultrasonic treatment, and high hydrostatic pressure. Thus, the aim of this review was to summarize the outcomes of treatment aimed at maintaining or increasing SAC levels in BG. Therefore, publications from scientific databases in this field of study were examined. The effects of processing methods on SAC compounds were evaluated on the basis of the SAC content. This review provides information on the processing approaches that can assist food manufacturers in the development of value-added garlic products.

Real-world management of targeted therapies in chronic lymphocytic leukemia

The advent of novel targeted therapies, including B-cell receptor (BCR) pathway and B-cell lymphoma 2 (BCL2) inhibitors, has substantially changed the treatment paradigm for chronic lymphocytic leukemia (CLL). Although targeted therapies have improved outcomes compared to traditional chemoimmunotherapy in the front-line and relapsed or refractory settings, they are associated with resistance mutations and suboptimal outcomes in certain high-risk patients. Additionally, targeted therapies are associated with drug interactions and unique adverse effect profiles which can be challenging for patients and clinicians to manage. Ongoing studies continue to address questions regarding optimal sequencing of therapies, the role of treatment combinations, and the efficacy of next-generation novel agents. This review provides a comprehensive overview regarding the clinical management of targeted therapies for CLL and applies current literature to clinical practice.

Virtual screening of functional foods and dissecting their roles in modulating gene functions to support post COVID-19 complications

COVID-19 has become the focal point since 2019 after the outbreak of coronavirus disease. Many drugs are being tested and used to treat coronavirus infections; different kinds of vaccines are also introduced as preventive measure. Alternative therapeutics are as well incorporated into the health guidelines of some countries. This research aimed to look into the underlying mechanisms of functional foods and how they may improve the long-term post COVID-19 cardiovascular, diabetic, and respiratory complications through their bioactive compounds. The potentiality of nine functional foods for post COVID-19 complications was investigated through computational approaches. A total of 266 bioactive compounds of these foods were searched via extensive literature reviewing. Three highly associated targets namely troponin I interacting kinase (TNNI3K), dipeptidyl peptidase 4 (DPP-4), and transforming growth factor beta 1 (TGF-β1) were selected for cardiovascular, diabetes, and respiratory disorders, respectively, after COVID-19 infections. Best docked compounds were further analyzed by network pharmacological tools to explore their interactions with complication-related genes (MAPK1 and HSP90AA1 for cardiovascular, PPARG and TNF-alpha for diabetes, and AKT-1 for respiratory disorders). Seventy-one suggested compounds out of one-hundred and thirty-nine (139) docked compounds in network pharmacology recommended 169 Gene Ontology (GO) items and 99 Kyoto Encyclopedia of Genes and Genomes signaling pathways preferably AKT signaling pathway, MAPK signaling pathway, ACE2 receptor signaling pathway, insulin signaling pathway, and PPAR signaling pathway. Among the chosen functional foods, black cumin, fenugreek, garlic, ginger, turmeric, bitter melon, and Indian pennywort were found to modulate the actions. Results demonstrate that aforesaid functional foods have attenuating roles to manage post COVID-19 complications. PRACTICAL APPLICATIONS: Functional foods have been approaching a greater interest due to their medicinal uses other than gastronomic pleasure. Nine functional food resources have been used in this research for their traditional and ethnopharmacological uses, but their directive-role in modulating the genes involved in the management of post COVID-19 complications is inadequately studied and reported. Therefore, the foods types used in this research may be prioritized to be used as functional foods for ameliorating the major post COVID-19 complications through appropriate science.

Improving the bioavailability and bioactivity of garlic bioactive compounds via nanotechnology

This review highlights main bioactive compounds and important biological functions especially anticancer effects of the garlic. In addition, we review current literature on the stability and bioavailability of garlic components. Finally, this review aims to provide a potential strategy for using nanotechnology to increase the stability and solubility of garlic components, providing guidelines for the qualities of garlic products to improve their absorption and prevent their early degradation, and extend their circulation time in the body. The application of nanotechnology to improve the bioavailability and targeting of garlic compounds are expected to provide a theoretical basis for the functional components of garlic to treat human health. We review the improvement of bioavailability and bioactivity of garlic bioactive compounds via nanotechnology, which could promisingly overcome the limitations of conventional garlic products, and would be used to prevent and treat cancer and other diseases in the near future.

Sulfur-containing Secondary Metabolites as Neuroprotective Agents

Sulfur-containing secondary metabolites are a relatively small group of substances of plant origin. The present review is focused on their neuroprotective properties. The results obtained in a series of in vitro and in vivo studies are reported. Among glucosinolates, the wide class of compounds in the sulfur-containing metabolites, glucoraphanin, sulforaphane and isothiocyanates proved to be the more studied in this context and showed interesting properties as modulators of several systems involved in the pathogenesis of neurologic diseases such as oxidative stress, inflammation and apoptosis. Allium sativum L. (garlic) is widely known for its sulfur-containing components endowed with health-promoting activities and its medicinal properties are known from ancient times. In recent studies, garlic components proved active in neuroprotection due to the direct and indirect antioxidant properties, modulation of apoptosis mediators and inhibiting the formation of amyloid protein. Dihydroasparagusic acid, the first dimercaptanic compound isolated from a natural source, effectively inhibited inflammatory and oxidative processes that are important factors for the etiopathogenesis of neurodegenerative diseases, not only for its antioxidant and radical scavenging properties but also because it may down-regulate the expression of several microglial-derived inflammatory mediators. Serofendic acid represents a rare case of sulfur-containing animal-derived secondary metabolite isolated from fetal calf serum extract. It proved effective in the suppression of ROS generation and in the expression of several inflammatory and apoptosis mediators and showed a cytotrophic property in astrocytes, promoting the stellation process. Lastly, the properties of hydrogen sulfide were also reported since in recent times it has been recognized as a signaling molecule and as a mediator in regulating neuron death or survival. It may be produced endogenously from cysteine but may also be released by sulfur-containing secondary metabolites, mainly from those present in garlic.

Prevailing Knowledge on the Bioavailability and Biological Activities of Sulphur Compounds from Alliums: A Potential Drug Candidate

Allium sativum (garlic) is widely known and is consumed as a natural prophylactic worldwide. It produces more than 200 identified chemical compounds, with more than 20 different kinds of sulfide compounds. The sulfide compounds particularly are proven to contribute to its various biological roles and pharmacological properties such as antimicrobial, antithrombotic, hypoglycemic, antitumour, and hypolipidemic. Therefore, it is often referred as disease-preventive food. Sulphur-containing compounds from A. sativum are derivatives of S-alkenyl-l-cysteine sulfoxides, ajoene molecules, thiosulfinates, sulfides, and S-allylcysteine. This review presents an overview of the water-soluble and oil-soluble sulphur based phytochemical compounds present in garlic, highlighting their mechanism of action in treating various health conditions. However, its role as a therapeutic agent should be extensively studied as it depends on factors such as the effective dosage and the suitable method of preparation.

Medicinal Plants as a Potential and Successful Treatment Option in the Context of Atherosclerosis

Atherosclerosis is a chronic multifactorial disease characterized by mainly changes of blood lipids profile and inflammation in vessel wall. The cardiovascular disease based on atherosclerosis is currently the leading cause of mortality in developed countries. Therefore, timely prevention and therapy of atherosclerosis are able to reduce the risk of the development of its clinical manifestations. Anti-atherosclerotic activity of medicinal plants mainly appears in their multiple effects such as anti-inflammatory, antioxidant, anti-atherogenic, hypotensive, lipid-lowering, anti-thrombotic. Moreover, most of medicinal plants are characterized by their pleiotropic anti-atherosclerotic action. In addition, the medicinal plants-derived pharmacological substances and/or compounds are characterized by relative safety and fewer side effects that allows considering them as one of potential anti-atherosclerotic effective agents. The direct anti-atherosclerotic effect of some medicinal plants was confirmed in clinical trials of carotid Intima-media thickness (IMT) progression during long-term medication with medicinal plants. This review attempted to determine the current status of the databases PubMed and Scopus (until November, 2019) to investigate the medicinal plants possessing anti-atherosclerotic activity in experimental and clinical studies.

Assessment of routine diet (garlic consumption) as a pre- and postoperative protocol in oral and maxillofacial surgical interventions: An evidence-based literature review

BACKGROUND

It was hypothesized that pathological bleeding (PB) during and/or after oral surgical procedures is higher in systemically healthy patients who have a history of garlic intake compared to controls (patients without a history of garlic consumption).

AIM

The aim of the present review article was to identify studies in which garlic consumption was included as a patient management protocol before and after oral and maxillofacial surgery (OMFS).

METHODS

A review of pertinent indexed literature was performed. The focused question that was addressed was "Has diet (garlic consumption) been considered as a patient management protocol before and after OMFS?" The inclusion criteria were: (a) studies published in indexed databases, (b) original studies, (c) studies on OMFS, and (d) studies that considered diet (garlic consumption) as a patient management protocol before and after OMFS. Literature review, commentaries, letters to the editor, and studies published in non-indexed resources were excluded. The pattern of the present review was customized to summarize the pertinent information.

RESULTS

The initial search using the terms "oral," maxillofacial," "protocol," and "surgery" yielded 1478 studies. The addition of the term "diet" to this search strategy reduced the number of studies to five. Further filtration of these studies using the terms "garlic" and/or "Allium sativum" showed no studies.

CONCLUSIONS

Garlic intake predisposes patients to PB. However, there are no studies in the indexed literature that have considered the inclusion of garlic consumption in patient management protocols before and after OMFS.

Decrease in Efficacy of Warfarin as a Result of Drug-Drug Interaction (Case Report)

The one of the main aims in modern clinical pharmacology is to provide safe and effective therapy considering a frequent administration of several drugs having different drug-drug interactions. Warfarin belongs to the number of popular anticoagulants which along with its efficiency not infrequently alters anticoagulant characteristics when administered with other drugs and food products. A case of a decrease in the efficacy of warfarin in a patient with mitral stenosis while taking a combined choleretic drug is presented in the article. The components of this choleretic drug (dry animal bile, dry garlic extract, dry nettle extract, activated charcoal) could impair the absorption of warfarin, increase intestinal absorption of vitamin K, and have a negative effect on the anticoagulant effect of warfarin. Management of patients receiving anticoagulants should be performed in accordance with clinical recommendations. Prescription of drugs, including multicomponent ones, without proven efficacy, for such patients should be considering the potential drug interaction.

Garlic lowers blood pressure in hypertensive subjects, improves arterial stiffness and gut microbiota: A review and meta-analysis

Garlic supplements have shown effectiveness in reducing blood pressure in hypertensive patients, similarly to first-line standard anti-hypertensive medications. Kyolic garlic has also shown promise in improving cardiovascular health by reducing arterial stiffness, elevated cholesterol levels and blood 'stickiness'. In addition, the prebiotic properties in garlic increase gut microbial richness and diversity. This article systematically reviews previously published trials investigating the effects of garlic on blood pressure, and provides an updated meta-analysis of hypertensive participants. In addition, we summarise the findings of recent clinical trials investigating the effects of Kyolic aged garlic extract on arterial stiffness, and gut microbiota in hypertensive subjects. We searched online electronic databases, including PubMed and Google Scholar for randomised controlled trials (RCTs) published between 1955 and December, 2018 examining the effects of garlic on high blood pressure. The meta-analysis of 12 trials and 553 hypertensive participants confirmed that garlic supplements lower systolic blood pressure (SBP) by an average of 8.3±1.9 mmHg and diastolic blood pressure (DBP, n=8 trials, n=374 subjects) by 5.5±1.9 mmHg, similarly to standard anti-hypertensive medications. This reduction in blood pressure was associated with a 16-40% reduction in the risk of suffering from cardiovascular events. Additionally, this review summarises new evidence for the vitamin B12 status playing an important role in the responsiveness of blood pressure to garlic. Furthermore, Kyolic aged garlic extract significantly lowered central blood pressure, pulse pressure, pulse wave velocity and arterial stiffness, and improved the gut microbiota, evidenced by higher microbial richness and diversity, with a marked increase in the numbers of Lactobacillus and Clostridia species found following 3 months of supplementation. Thus, Kyolic aged garlic extract is considered to be highly tolerable with a high safety profile either as a stand-alone or adjunctive anti-hypertensive treatment, with multiple benefits for cardiovascular health.

New Aspects Towards a Molecular Understanding of the Allicin Immunostimulatory Mechanism via Colec12, MARCO, and SCARB1 Receptors

The allicin pleiotropic effects, which include anti-inflammatory, anti-oxidant, anti-tumoral, and antibacterial actions, were well demonstrated and correlated with various molecular pathways. The immunostimulatory mechanism of allicin has not been elucidated; however, there is a possible cytokine stimulation from immunoglobulin release caused by allicin. In this study, when Wistar female rats and CD19+ lymphocytes were treated with three different doses of allicin, immunoglobulins, glutathione, and oxidative stress markers were assayed. Molecular docking was performed between S-allylmercaptoglutathione (GSSA)—a circulating form of allicin in in vivo systems formed by the allicin interaction with glutathione (GSH)—and scavenger receptors class A and B from macrophages, as well as CD19+ B lymphocytes. Our data demonstrated a humoral immunostimulatory effect of allicin in rats and direct stimulation of B lymphocytes by S-allyl-mercapto-glutathione, both correlated with decreased catalase (CAT) activity. The molecular docking revealed that S-allyl-mercapto-glutathione interacting with Colec12, MARCO (class A), and SCARB1 (class B) scavenger receptors in in vitro tests demonstrates a direct stimulation of immunoglobulin secretion by GSSA in CD19+ B lymphocytes. These data collectively indicate that GSSA stimulates immunoglobulin secretion by binding on scavenger receptors class B type 1 (SCARB1) from CD19+ B lymphocytes.

rLj-RGD3, a novel recombinant toxin protein from Lampetra japonica, prevents coronary thrombosis-induced acute myocardial infarction by inhibiting platelet functions in rats

Recombinant Lampetra japonica RGD-peptide (rLj-RGD3), a soluble protein containing three RGD sequences, was acquired from the oral salivary glands of Lampetra japonica using recombinant DNA technology. The aim of this study was to investigate the protective effects of rLj-RGD3 against acute myocardial infarction (AMI) induced by coronary artery thrombosis, as well as the underlying mechanisms. A rat model of AMI caused by ferric chloride-induced thrombosis on the surface of the left anterior descending (LAD) coronary artery was successfully established. Rats were given various doses of rLj-RGD3 (12 μg/kg, 24 μg/kg and 48 μg/kg) via sublingual intravenous delivery 10 min before AMI. ST segment elevation was recorded by electrocardiogram (ECG) until the end of the model. Left ventricular Evans blue content and histopathological changes were examined. Blood samples were collected to determine 5-hydroxytryptamine (5-HT), β-thromboglobulin (β-TG), platelet factor 4 (PF4) and cAMP levels. The effects of rLj-RGD3 on platelet aggregation, adhesion and intracellular calcium concentrations were also measured. rLj-RGD3 significantly reduced ST segment elevation, prevented thrombus formation in the coronary artery and decreased Evans blue content in the left ventricular myocardium. Meanwhile, rLj-RGD3 exerted an inhibitory effect on adenosine diphosphate (ADP)-induced platelet aggregation and blocked platelet adhesion to collagen. Treatment with rLj-RGD3 prevented 5-HT, β-TG and PF4 release and significantly elevated intracellular cAMP levels in a dose-dependent manner but decreased the level of cytosolic-free Ca²⁺, an aggregation-inducing molecule. These results show that rLj-RGD3 can effectively reduce coronary thrombosis in AMI rats by strongly inhibiting platelet function, indicating that the recombinant RGD toxin protein rLj-RGD3 may serve as a potent clinical therapeutic agent for AMI.

Characterization of garlic endophytes isolated from the black garlic processing

The objectives of this study were to isolate and identify garlic endophytes, and explore the characteristics of dominant strains. Garlic endophytes were studied through phenotypical characterization and comparative sequence analysis of 16S rDNA based on culture‐dependent approaches. Representative strains inferred from 16S rDNA sequencing were selected for further identification by gyrA and rpoB gene loci and phylogenetic analysis based on concateneted house‐keeping sequences. Seven kinds of Bacillus were found from garlic and black garlic, respectively. Further studies demonstrated that the total bacteria and endophytes showed a sharp decrease firstly, followed by a rapid rise, then maintained at a certain level, and finally slowed down during the black garlic processing. B. subtilis, B. methylotrophicus, and B. amyloliquefaciens were the dominant strains. The selected strains were capable of fermenting glucose, lactose, sucrose, and garlic polysaccharide to produce acid but no gas, with a strong ability of heat resistance. The results indicated that there were a certain number of garlic endophytes during the black garlic processing, and Bacillus was the dominant strains under the conventional culture‐dependent methods. This report provided useful information for the presence and type of garlic endophytes during the black garlic processing, which were of great significance to study the formation mechanism and quality improvement of black garlic in the future, as well as the security of garlic powder.

Community pharmacists' knowledge, practices and beliefs about complementary and alternative medicine in Palestine: a cross-sectional study

BACKGROUND

Complementary and alternative medicine (CAM) utilization is dramatically increasing among patients. As community pharmacies are a major provider of CAM products, community pharmacists need to have the sufficient knowledge and information to advice their patients, answer their inquiries and to be proactive in the healthcare process to ensure optimal therapy outputs and minimize both drug-drug and drug-herb interactions. Therefore, the main objective of this study was to assess the knowledge, beliefs, and practices of community pharmacists in Palestine about CAM.

METHODS

The study was conducted in a cross-sectional design in which a questionnaire was administered on a sample of licensed community pharmacists from Palestine. The questionnaire was of 5 sections: demographic and practice details of the participants, practice, beliefs, and knowledge about CAM. Mann-Whitney-U or Kruskal-Wallis tests were used to comparison of different issues as appropriate. P-values of <0.05 were considered significant.

RESULTS

A total of 284 community pharmacists were surveyed, however, 281 were included in the analysis as they met inclusion criteria. Out of the 281, 149 (53.0%) of the participants were males and the rest were females. About 40% of the participants were between 20 to 29 years old. Pharmacists frequently recommended CAM modalities. Exercises (84.0%) and food supplements (82.6%) were the most commonly recommended modalities. In the last year, vitamin B12 was the most frequently prescribed supplement. The median knowledge score was 5 out of 8 and the median beliefs about CAM score was 4.0 out of 7.0.

CONCLUSIONS

CAM recommendations by pharmacists appear to be commonplace. Although their knowledge scores were fair to average, pharmacists still need more education and training about CAM in order to be more qualified to provide better pharmaceutical care and improve their patient's outcome.

The Health Potential of Fruits and Vegetables Phytochemicals: Notable Examples

Fruit and vegetables are essential components of a healthy diet. The World Health Organization (WHO) recommends an intake of five to eight portions (400-600 g) daily of fruits and vegetables to reduce risk of cardiovascular disease, cancer, poor cognitive performance, and other diet-related diseases, as well as for the prevention of micronutrient deficiencies. Much of their potential for disease prevention is thought to be provided by phytochemicals, among which the preventive activity of antioxidants is most well documented. Since numerous meta-studies published indicate variable and often contradictory results about the impact of isolated phytochemicals on health, their consumption as supplements must be carried out with care, because doses may exceed the recommended nutritional intake. Nonetheless, there is a general consensus that whole fruit and vegetable intake is more important in providing health benefits than that of only one of their constituent, because of additive and synergistic effects. This review describes the most recent literature regarding the health benefits of some selected fruits and vegetables. Importantly, since some phytochemicals regulate the same genes and pathways targeted by drugs, diets rich in fruits and vegetables in combination with medical therapies are being considered as novel approaches to treatment. Therefore, phytochemicals in fruits and vegetable might be a promising tool for the prevention and/or amelioration of a wide range of diseases.

Garlic-Induced Surgical Bleeding: How Much Is Too Much?

A patient underwent C2-T2 decompression and fusion with excessive intraoperative bleeding and no clear source. The patient denied the use of blood-thinning medications, but had consumed the equivalent of 12 g garlic daily in the days leading up to the surgery. He was treated with desmopressin acetate (DDAVP) and cryoprecipitate with adequate control of bleeding. Garlic is known to have an antiplatelet effect, although the dose range necessary to create a bleeding abnormality has not yet been well described nor has the effect of taking garlic with sertraline or other agents with an established or potential effect on coagulation.

A Comprehensive Review on Rasam: A South Indian Traditional Functional Food

The view that food can have an expanded role that goes well beyond providing a source of nutrients truly applies to traditional functional foods. The systematic consumption of such traditional functional food provides an excellent preventive measure to ward off many diseases. Rasam, a soup of spices, is a traditional South Indian food. It is traditionally prepared using tamarind juice as a base, with the addition of Indian sesame oil, turmeric, tomato, chili pepper, pepper, garlic, cumin, curry leaves, mustard, coriander, asafoetida, sea salt, and water. Rasam is a classic example of traditional functional food with all its ingredients medicinally claimed for various ailments. The preclinical and clinical studies on rasam and its ingredients support their traditional claim. This review is an attempt to compile the literatures on rasam, its ingredients, and to highlight its medicinal potential that has been underestimated.

Development of a Method and Validation for the Quantitation of FruArg in Mice Plasma and Brain Tissue Using UPLC-MS/MS

Aged garlic extract (AGE) is a popular nutritional supplement and is believed to promote health benefits by exhibiting antioxidant and anti-inflammatory activities and hypolipidemic and antiplatelet effects. We have previously identified N-α-(1-deoxy-d-fructos-1-yl)-l-arginine (FruArg) as a major contributor to the bioactivity of AGE in BV-2 microglial cells whereby it exerted a significant ability to attenuate lipopolysaccharide-induced neuroinflammatory responses and to regulate the Nrf2-mediated antioxidant response. Here, we report on a sensitive ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) protocol that was validated for the quantitation of FruArg in mouse plasma and brain tissue samples. Solid-phase extraction was used to separate FruArg from proteins and phospholipids present in the biological fluids. Results indicated that FruArg was readily absorbed into the blood circulation of mice after intraperitoneal injections. FruArg was reliably detected in the subregions of the brain tissue postinjection, indicating that it penetrates the blood-brain barrier in subnanomolar concentrations that are sufficient for its biological activity.

Effects of aged garlic extract and FruArg on gene expression and signaling pathways in lipopolysaccharide-activated microglial cells

Aged garlic extract (AGE) is widely used as a dietary supplement on account of its protective effects against oxidative stress and inflammation. But less is known about specific molecular targets of AGE and its bioactive components, including N-α-(1-deoxy-D-fructos-1-yl)-L-arginine (FruArg). Our recent study showed that both AGE and FruArg significantly attenuate lipopolysaccharide (LPS)-induced neuroinflammatory responses in BV-2 microglial cells. This study aims to unveil effects of AGE and FruArg on gene expression regulation in LPS stimulated BV-2 cells. Results showed that LPS treatment significantly altered mRNA levels from 2563 genes. AGE reversed 67% of the transcriptome alteration induced by LPS, whereas FruArg accounted for the protective effect by reversing expression levels of 55% of genes altered by LPS. Key pro-inflammatory canonical pathways induced by the LPS stimulation included toll-like receptor signaling, IL-6 signaling, and Nrf2-mediated oxidative stress pathway, along with elevated expression levels of genes, such as Il6, Cd14, Casp3, Nfkb1, Hmox1, and Tnf. These effects could be modulated by treatment with both AGE and FruArg. These findings suggests that AGE and FruArg are capable of alleviating oxidative stress and neuroinflammatory responses stimulated by LPS in BV-2 cells.

Chemical composition and bioactive compounds of garlic (Allium sativum L.) as affected by pre- and post-harvest conditions: A review

Garlic (Allium sativum L.) is considered one of the twenty most important vegetables, with various uses throughout the world, either as a raw vegetable for culinary purposes, or as an ingredient of traditional and modern medicine. Furthermore, it has also been proposed as one of the richest sources of total phenolic compounds, among the usually consumed vegetables, and has been highly ranked regarding its contribution of phenolic compounds to human diet. This review aims to examine all the aspects related with garlic chemical composition and quality, focusing on its bioactive properties. A particular emphasis is given on the organosulfur compounds content, since they highly contribute to the effective bioactive properties of garlic, including its derived products. The important effects of pre-harvest (genotype and various cultivation practices) and post-harvest conditions (storage conditions and processing treatments) on chemical composition and, consequently, bioactive potency of garlic are also discussed.

Aged Garlic Extract Inhibits Human Platelet Aggregation by Altering Intracellular Signaling and Platelet Shape Change

BACKGROUND

Increased platelet aggregation plays a pivotal role in the etiology of cardiovascular disease. Upon platelet aggregation, an increase in free cytoplasmic Ca(2+) results in the inhibition of soluble guanylyl cyclase (sGC) and adenylyl cyclase (AC), leading to a decrease in cyclic guaninosine-5'-monophosphate (cGMP) and cAMP, respectively. This leads to the activation of the glycoprotein IIb/IIIa (GPIIb/IIIa) fibrinogen receptor, resulting in platelet shape change. Aged garlic extract (AGE) decreases platelet aggregation; however, the mechanisms involved are not clearly defined.

OBJECTIVE

Our objective was to investigate the effects of AGE on intraplatelet cell signaling and platelet shape change.

METHODS

Platelets from 14 participants were studied. Platelet aggregation was induced by ADP in the presence of AGE up to a concentration of 6.25% (vol:vol) alone or in combination with 3-morpholinosydnonimine (Sin-1), a nitric oxide donor. The experiments with AGE were repeated in the presence of 3-isobutyl-1-methylxanthine (IBMX), a phosphodiesterase inhibitor. In a series of separate experiments, platelet aggregation was induced in the presence of either 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), an sGC inhibitor, or 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (SQ22536), an AC inhibitor, or a combination of both in the presence of IBMX and AGE. Intraplatelet cGMP and cAMP were measured. The platelets were also subjected to scanning electron microscopic analysis, and their binding to fibrinogen was determined.

RESULTS

AGE decreased platelet aggregation at all concentrations tested; this decrease was more marked in the presence of Sin-1 and ranged between 15% and 67%.The presence of IBMX also led to a decrease (17-35%) in platelet aggregation at all AGE concentrations and a significant decrease in the amounts of cGMP (24-41%) and cAMP (19-70%), respectively, in the presence of ODQ and SQ22536. The presence of AGE significantly inhibited the binding of activated platelets to fibrinogen, preventing changes in platelet shape.

CONCLUSION

These results indicate that AGE inhibits platelet aggregation by increasing cyclic nucleotides and inhibiting fibrinogen binding and platelet shape change.

Commonly Used Dietary Supplements on Coagulation Function during Surgery

BACKGROUND

Patients who undergo surgery appear to use dietary supplements significantly more frequently than the general population. Because they contain pharmacologically active compounds, dietary supplements may affect coagulation and platelet function during the perioperative period through direct effects, pharmacodynamic interactions, and pharmacokinetic interactions. However, in this regard, limited studies have been conducted that address the pharmacological interactions of dietary supplements. To avoid possible bleeding risks during surgery, information of potential complications of dietary supplements during perioperative management is important for physicians.

METHODS

Through a systematic database search of all available years, articles were identified in this review if they included dietary supplements and coagulation/platelet function, while special attention was paid to studies published after 1990.

RESULTS

Safety concerns are reported in commercially available dietary supplements. Effects of the most commonly used natural products on blood coagulation and platelet function are systematically reviewed, including 11 herbal medicines (echinacea, ephedra, garlic, ginger, ginkgo, ginseng, green tea, kava, saw palmetto, St John's wort, and valerian) and 4 other dietary supplements (coenzyme Q₁₀, glucosamine and chondroitin sulfate, fish oil, and vitamins). Bleeding risks of garlic, ginkgo, ginseng, green tea, saw palmetto, St John's wort, and fish oil are reported. Cardiovascular instability was observed with ephedra, ginseng, and kava. Pharmacodynamic and pharmacokinetic interactions between dietary supplements and drugs used in the perioperative period are discussed.

CONCLUSIONS

To prevent potential problems associated with the use of dietary supplements, physicians should be familiar with the perioperative effects of commonly used dietary supplements. Since the effects of dietary supplements on coagulation and platelet function are difficult to predict, it is prudent to advise their discontinuation before surgery.

Natural Products for Antithrombosis

Thrombosis is considered to be closely related to several diseases such as atherosclerosis, ischemic heart disease and stroke, as well as rheumatoid arthritis, hyperuricemia, and various inflammatory conditions. More and more studies have been focused on understanding the mechanism of molecular and cellular basis of thrombus formation as well as preventing thrombosis for the treatment of thrombotic diseases. In reality, there is considerable interest in the role of natural products and their bioactive components in the prevention and treatment of thrombosis related disorders. This paper briefly describes the mechanisms of thrombus formation on three aspects, including coagulation system, platelet activation, and aggregation, and change of blood flow conditions. Furthermore, the natural products for antithrombosis by anticoagulation, antiplatelet aggregation, and fibrinolysis were summarized, respectively.

Effect of Selenium-Enriched Garlic Oil against Cytotoxicity Induced by OX-LDL in Endothelial Cells

Objective. To detect the effect of selenium-enriched garlic oil (Se-garlic oil) against cytotoxicity induced by ox-LDL in endothelial cells. Methods. Se-garlic oil was extracted by organic solvent extraction. High performance liquid chromatography (HPLC) was used to detect the content of allicin in the Se-garlic oil. Hydride generation atomic fluorescence spectrometry (HG-AFS) was used to detect the content of Se in the Se-garlic oil. ECV-304 cells were separated into five groups (blank, ox-LDL, and low-, medium-, and high-dose Se-garlic oil). Methyl thiazolyl tetrazolium (MTT) assay was used to detect the cytoactivity of each cell group after culturing for 24, 48, and 72 hours. Flow cytometry (FCM) stained with annexin V-FITC/PI was used to detect the apoptosis of the cells from the blank, Se-garlic oil, ox-LDL, and Se-garlic oil + ox-ldl groups after 48 hours of incubation. Results. The amount of allicin in Se-garlic oil was 142.66 mg/ml, while, in Se, it was 198 mg/kg. When ox-LDL was added to low-, medium-, and high-dose Se-garlic oil, the cell viability rates of ECV-304 cells treated in the three groups were all higher, while the apoptosis rates were significantly lower than those of the ox-LDL group (P < 0.05). However, there was no significant difference between the apoptosis rates of the blank, Se-garlic oil, and Se-garlic oil + ox-LDL groups (P > 0.05). Conclusion. Se-garlic oil could inhibit the cytotoxic effect induced by ox-LDL in endothelial cells.

Inhibition of platelet activation by lachrymatory factor synthase (LFS)-silenced (tearless) onion juice

Onion and garlic are renowned for their roles as functional foods. The health benefits of garlic are attributed to di-2-propenyl thiosulfinate (allicin), a sulfur compound found in disrupted garlic but not found in disrupted onion. Recently, onions have been grown with repressed lachrymatory factor synthase (LFS) activity, which causes these onions to produce increased amounts of di-1-propenyl thiosulfinate, an isomer of allicin. This investigation into the key health attributes of LFS-silenced (tearless) onions demonstrates that they have some attributes more similar to garlic and that this is likely due to the production of novel thiosulfinate or metabolites. The key finding was that collagen-induced in vitro platelet aggregation was significantly reduced by tearless onion extract over normal onion extract. Thiosulfinate or derived compounds were shown not to be responsible for the observed changes in the inflammatory response of AGS (stomach adenocarcinoma) cells to tumor necrosis factor alpha (TNFα) when pretreated with model onion juices. A preliminary rat feeding trial indicated that the tearless onions may also play a key role in reducing weight gain.

Role of garlic usage in cardiovascular disease prevention: an evidence-based approach

Introduction. Rapidly growing prevalence of cardiovascular disease is a major threat for the developed as well as developing world warranting urgent need of intervention. Complementary and alternative medicines are gaining popularity among general population because of their safety profile and easy administration. Garlic, in particular, is considered to be one of the best disease-preventive foods because of its potent and widespread effects. This study was done to find out the role of garlic usage in cardiovascular disease prevention. Methodology. Major databases including Google, PubMed, MEDLINE, and Cochrane library view were used for the literature search. Clinical trials conducted on humans assessing role of garlic usage in cardiovascular disease prevention and the possible mechanisms responsible for such therapeutic actions were assessed. Results. Various clinical trials and meta-analyses conducted have shown positive impact of garlic in cardiovascular-disease prevention especially its effects on lipid levels; however, some contradictory results are also reported. Similarly, its effects on hypertension control, and platelet are also mild with limited data availability. The possible reason for these inconsistent results is the difference in preparations with diverse composition, variations in sulphur content present in different garlic preparations used, and methodological variations in subject recruitment, duration of study, dietary control and so forth. Conclusion. Garlic can be used as an adjuvant with lipid-lowering drugs for control of lipids, however, its role as a main therapeutic agent cannot be recommended and it is suggested that more meta-analyses using standardized preparations with a close watch on methodological shortfalls should be conducted to prove its role.

Garlic and cardioprotection: insights into the molecular mechanisms

Garlic is widely recognized for its immense therapeutic potential. Garlic has been shown to exert its beneficial effects against a wide spectrum of diseases, including cancer, diabetes, and microbial infections, as well as immunological and cardiovascular disorders. Most of the research on garlic has indicated that garlic and its active compounds are effective in reducing cardiovascular and metabolic risk by normalizing abnormal plasma lipids, oxidized low density lipoproteins, abnormal platelet aggregation, high blood pressure, and cardiac injury. Some of the beneficial effects of dietary garlic against cardiovascular disorders are mediated via the generation of hydrogen sulfide and nitric oxide in cardiomyocytes and endothelial cells. Garlic has the potential to protect the heart against myocardial infarction, doxorubicin-induced cardiotoxicity, arrhythmia, hypertrophy, and ischemia-reperfusion injury. The induction of cardiac endogenous antioxidants and the reduction of lipid peroxidation by garlic has been reported by several different groups. Other mechanisms, such as regulating ion channels, modulating Akt signaling pathways, histone deacetylase inhibition, and cytochrome P450 inhibition, could be responsible for the cardioprotective effect of garlic. Although several mechanisms have been identified for the cardioprotective effect of garlic, there is a need for further research to identify the specific molecular mechanism of cardioprotection in different cardiac diseases.

A novel antithrombotic effect of sulforaphane via activation of platelet adenylate cyclase: ex vivo and in vivo studies

Sulforaphane is a naturally occurring isothiocyanate, which can be found in cruciferous vegetables such as broccoli and cabbage. Sulforaphane was found to have very potent inhibitory effects on tumor growth through regulation of diverse mechanisms. However, no data are available concerning the effects of sulforaphane on platelet activation and its relative issues. Activation of platelets caused by arterial thrombosis is relevant to a variety of cardiovascular diseases. Hence, the aim of this study was to examine the in vivo antithrombotic effects of sulforaphane and its possible mechanisms in platelet activation. Sulforaphane (0.125 and 0.25 mg/kg) was effective in reducing the mortality of ADP-induced acute pulmonary thromboembolism in mice. Other in vivo studies also revealed that sulforaphane (0.25 mg/kg) significantly prolonged platelet plug formation in mice. In addition, sulforaphane (15-75 μM) exhibited more-potent activity of inhibiting platelet aggregation stimulated by collagen. Sulforaphane inhibited platelet activation accompanied by inhibiting relative Ca(2+) mobilization; phosphorylation of phospholipase C (PLC)γ2, protein kinase C (PKC), mitogen-activated protein kinases (MAPKs) and Akt; and hydroxyl radical (OH(●)) formation. Sulforaphane markedly increased cyclic (c)AMP, but not cyclic (c)GMP levels, and stimulated vasodilator-stimulated phosphoprotein (VASP) phosphorylation. SQ22536, an inhibitor of adenylate cyclase, but not ODQ (1H-[1,2,4]Oxadiazolo[4,3-a]quinoxal in-1-one), an inhibitor of guanylate cyclase, obviously reversed the sulforaphane-mediated effects on platelet aggregation; PKC activation, p38 MAPK, Akt and VASP phosphorylation; and OH(●) formation. Furthermore, a PI3-kinase inhibitor (LY294002) and a p38 MAPK inhibitor (SB203580) both significantly diminished PKC activation and p38 MAPK and Akt phosphorylation; in contrast, a PKC inhibitor (RO318220) did not diminish p38 MAPK or Akt phosphorylation stimulated by collagen. This study demonstrates for the first time that in addition to it originally being considered as an agent for prevention of tumor growth, sulforaphane possesses potent antiplatelet activity which may initially activate adenylate cyclase/cAMP, followed by inhibiting intracellular signals (such as the PI3-kinase/Akt and PLCγ2-PKC-p47 cascades) and ultimately inhibiting platelet activation. Therefore, this novel role of sulforaphane may represent a high therapeutic potential for treatment or prevention of cardiovascular diseases.

Aged garlic extract inhibits platelet activation by increasing intracellular cAMP and reducing the interaction of GPIIb/IIIa receptor with fibrinogen

AIMS

Increased platelet aggregation plays an important role in the etiology of cardiovascular disease. Garlic inhibits platelet aggregation; however, the mechanisms involved have not clearly been defined. This study was undertaken to investigate the mechanisms by which an aged garlic extract (AGE) inhibits both the activation and aggregation of human platelets.

MAIN METHODS

Isolated human platelets were stimulated with ADP and their adhesion to fibrinogen was assessed using Rose Bengal or (51)Cr uptake. Activation of platelets was assessed using fluorescence activated cell sorting (FACS) analysis along with measurement of intracellular cAMP.

KEY FINDINGS

AGE at concentrations in the range of 3.12 to 12.5% (v/v) inhibited the binding of platelets to fibrinogen by approximately 40% when compared to control values in the Rose Bengal assay (P<0.05). In the (51)Cr experiments AGE significantly inhibited the binding of ADP-activated platelets to immobilized fibrinogen by 61.5% at 1.56% and 6.25% (v/v) of AGE respectively. At a concentration of 12.5% (v/v) the inhibition was 70.4% and at 25% (v/v) it was 64.5% respectively (P<0.05). In the fluorescence activated cell sorting (FACS) analysis, AGE significantly decreased the amount of PAC-1 binding to GPIIb/IIIa by approximately 72% compared with PBS control. In conjunction to these observations, AGE also increased platelet cAMP (P<0.01) levels.

SIGNIFICANCE

These findings suggest that AGE inhibits platelet aggregation via inhibition of the GPIIb/IIIa receptor and an increase in cAMP.

Aged red garlic extract reduces lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages and acute pulmonary inflammation through haeme oxygenase-1 induction

AIM

It is known that garlic has antioxidative and anti-inflammatory properties. Aged red garlic (ARG), a novel aged garlic formulation, has higher antioxidant effects than fresh raw garlic. This study was performed to examine the anti-inflammatory effects of ARG extract (ARGE).

METHODS

The anti-inflammatory effects of ARGE were evaluated in the lipopolysaccharide (LPS)-treated Raw 264.7 macrophages and acute lung inflammatory mice. NO production was determined by the Griess method, and iNOS, HO-1 and COX-2 expressions were measured using Western blot analysis. Histology and inflammation extent of lung were analysed using haematoxylin-eosin staining and immunohistochemistry.

RESULTS

ARGE treatment markedly reduced LPS-induced nitrite production in RAW 264.7 macrophages and reduced inducible nitric oxide synthase (iNOS) expression. Treatment of cells with ARGE led to a significant increase in haeme oxygenase-1 (HO-1) protein expression, which was mediated by stimulating the expression of nuclear factor erythroid 2-related factor 2 (Nrf2). Treatment with zinc protoporphyrin, a selective inhibitor of HO-1, significantly reversed the ARGE-mediated inhibition of nitrite production (P < 0.05). In LPS-induced inflammatory mice, ARGE treatment down-regulated iNOS and COX-2 expressions, while it up-regulated HO-1 expression.

CONCLUSION

These results show that ARGE reduces LPS-induced nitric oxide production in RAW 264.7 macrophages through HO-1 induction and suggest that ARGE may have potential effects on prevention and treatment of acute inflammatory lung injury.

Garlic provides protection to mice heart against isoproterenol-induced oxidative damage: role of nitric oxide

Garlic has been widely recognized as a cardioprotective agent. However, the molecular mechanism of its cardioprotective effects is not well established. Here we hypothesized that aqueous garlic homogenate may mediate cardioprotection via nitric oxide (NO). Mice were fed with saline and aqueous garlic homogenate (250 and 500 mgkg(-1)day(-1) orally) for 30 days. In another set of experiment, mice were pre-treated with saline, aqueous garlic homogenate (AGH) (250 mgkg(-1)day(-1) for 30 days), and AGH (30 days) along with L-NAME (20 mgkg(-1)day(-1) i.p. for last 7 days) before inducing acute myocardial infarction by isoproterenol (s.c. injection of isoproterenol 150 mgkg(-1)day(-1) for 2 days) and sacrificed after 48 h. Dose dependent increase in serum NO level was observed after garlic 250 and 500 mgkg(-1) dose feeding. While no change in serum SGPT and SGOT level, a significant decrease in serum LDH level was observed after garlic feeding. Garlic-induced NO formation was further confirmed in human aortic endothelial cells (HAEC). Administration of isoproterenol caused a significant decrease in endogenous antioxidants i.e., myocardial catalase, GSH and GPx activity, and mitochondrial enzyme activities like citrate synthase and β hydroxyacyl CoA dehydrogenase. All those deleterious cardiac changes induced by isoproterenol were significantly attenuated by garlic homogenate. However this beneficial effect of garlic was blunted when garlic was administered with L-NAME, a nonspecific inhibitor of nitric oxide synthase (NOS). Further, a significant increase in myocardial TBARS and decrease in total antioxidant activity was observed in L-NAME treated group compared to isoproterenol treated group. Administration of L-NAME in mice from control group lowered serum and cardiac NO levels without any change of oxidative stress parameters. In conclusion, our study provides novel evidence that garlic homogenate is protective in myocardial infarction via NO-signaling pathway in mice.

In vitro assessment of oxidative stress and apoptotic mechanisms of garlic extract in the treatment of acute promyelocytic leukemia

INTRODUCTION

Garlic supplementation in diet has been shown to be beneficial to cancer patients. Recently, its pharmacological role in the prevention and treatment of cancer has received increasing attention. However, the mechanisms by which garlic extract (GE) induces cytotoxicity, oxidative stress, and apoptosis in cancer cells remain largely unknown.

OBJECTIVE

The present study was designed to use HL-60 cells as a test model to evaluate whether or not GE-induced cytotoxicty and apoptosis in human leukemia (HL-60) cells is mediated through oxidative stress.

METHODS

Human leukemia (HL-60) cells were treated with different concentrations of GE for 12 hr. Cell survival was determined by MTT assay. The extent of oxidative cell/tissue damage was determined by measuring malondialdehyde (lipid peroxidation biomarker) concentrations by spectrophotometry. Cell apoptosis was measured by flow cytometry assessment (Annexin-V and caspase-3 assays) and agarose gel electrophoresis (DNA laddering assay).

RESULTS

Data obtained from the MTT assay indicated that GE significantly (p < 0.05) reduced the viability of HL-60 cells in a concentration-dependent manner. We detected a significant (p < 0.05) increase in malondialdehyde (MDA) concentrations in GE-treated HL-60 cells compared to the control. Flow cytometry data showed a strong concentration-response relationship between GE exposure and Annexin-V positive HL-60 cells. Similarly, a statistically significant and concentration-dependent increase (p <0.05) were recorded with regard to caspase-3 activity in HL-60 cells undergoing late apoptosis. These results were confirmed by data of DNA laddering assay showing a clear evidence of nucleosomal DNA fragmentation in GE-treated cells.

CONCLUSION

Our finding indicates that GE-induced cytotoxicity and apoptosis in HL-60 cells involve phosphatidylserine externalization, caspase-3 activation, and nucleosomal DNA fragmentation associated with the formation of MDA, a by-product of lipid peroxidation and biomarker of oxidative stress. At therapeutic concentrations, GE-induced cytotoxic and apoptotic effects in HL-60 cells is mediated by oxidative stress.

Antiplatelet effects of Spatholobus suberectus via inhibition of the glycoprotein IIb/IIIa receptor

ETHNOPHARMACOLOGICAL RELEVANCE

The vine stem of Spatholobus suberectus is a widely used blood-activating and stasis-dispelling medicine for the treatment of diseases related to blood stasis syndrome in traditional medicine in Korea, Japan, and China.

AIM OF THE STUDY

To demonstrate the clinical effects of Spatholobus suberectus against blood stasis syndromes using in vitro and in vivo platelet aggregation studies and to investigate its exact mechanisms.

MATERIALS AND METHODS

We extracted vine stems of Spatholobus suberectus, using 95% EtOH (SSE) and investigated its antiplatelet activity on platelet aggregation induced by collagen and ADP in human platelet-rich plasma (PRP). For the mechanism study, a glycoprotein IIb/IIIa (GP IIb/IIIa) assay using flow cytometric analysis and a thromboxane A(2) (TXA(2)) assay were performed. In addition, we investigated the effects of SSE in a thromboembolic mouse model.

RESULTS

SSE significantly inhibited ADP- and collagen-induced platelet aggregation in human PRP concentration-dependently without affecting plasma clotting time. It also significantly inhibited fibrinogen binding to the GP IIb/IIIa receptor and partly inhibited the formation of TXA(2). In the in vivo study, oral administration of SSE dose-dependently suppressed the death of thromboembolism model mice induced by intravenous injection of collagen plus epinephrine.

CONCLUSIONS

SSE showed antiplatelet activity without anticoagulant effects mainly through the inhibition of fibrinogen binding to the GP IIb/IIIa receptor. Our current results support the clinical usage of SSE in the East Asian region treating atherothrombotic diseases and may represent a new natural source to develop antiplatelet agents.

Organosulfur compounds and cardiovascular disease

Epidemiological studies have shown an inverse relationship between consumption of fruits and vegetables and the risk of cardiovascular disease. Phytochemicals are non-nutritional chemical compounds found in small quantities in fruits and vegetables with known health benefits. Among them, organosulfides are present mainly in garlic and onion characterized by their antioxidant and anti-inflammatory properties, and isothiocyanates in cruciferous vegetables have anticarcinogenic effects in experimental models. In this review, we are focusing on the main biological studies regarding the beneficial effect of organosulfur compounds on their protection against cardiovascular disease.

Garlic extract induces intestinal P-glycoprotein, but exhibits no effect on intestinal and hepatic CYP3A4 in humans

Garlic extracts have been shown to decrease drug exposure for saquinavir, a P-glycoprotein and cytochrome P450 3A4 substrate. In order to explore the underlying mechanisms and to study the effects of garlic on pre-systemic drug elimination, healthy volunteers were administered garlic extract for 21 days. Prior to and at the end of this period, expression of duodenal P-glycoprotein and cytochrome P450 3A4 protein were assayed and normalized to villin, while hepatic cytochrome P450 3A4 function and simvastatin, pravastatin and saquinavir pharmacokinetics were also evaluated. Ingestion of garlic extract increased expression of duodenal P-glycoprotein to 131% (95% CI, 105-163%), without increasing the expression of cytochrome P450 3A4 which amounted to 87% (95% CI, 67-112%), relative to baseline in both cases. For the erythromycin breath test performed, the average result was 96% (95% CI, 83-112%). Ingestion of garlic extract had no effect on drug and metabolite AUCs following a single dose of simvastatin or pravastatin, although the average area under the plasma concentration curve (AUC) of saquinavir decreased to 85% (95% CI, 66-109%), and changes in intestinal P-glycoprotein expression negatively correlated with this change. In conclusion, garlic extract induces intestinal expression of P-glycoprotein independent of cytochrome P450 3A4 in human intestine and liver.