Diallyl trisulfide and diallyl disulfide ameliorate cardiac dysfunction by suppressing apoptotic and enhancing survival pathways in experimental diabetic rats

Diallyl Trisulfide and Cardiovascular Health: Evidence and Potential Molecular Mechanisms

Traditionally, garlic has a valuable role in preventing and reducing the incidence of many diseases and pathophysiological disorders. Consequently, some researchers have focused on the beneficial cardiovascular properties of diallyl trisulfide (DATS), the most potent polysulfide isolated from garlic. Therefore, in this review, we collected the available data on DATS, its biochemical synthesis, metabolism and pharmacokinetics, and gathered the current knowledge and the role of DATS in cardiovascular diseases. Overall, this review summarizes the cardioprotective effects of DATS and brings together all previous findings on its protective molecular mechanisms, which are mainly based on the potent anti-apoptotic, anti-inflammatory, and antioxidant potential of this polysulfide. Our review is an important cornerstone for further basic and clinical research on DATS as a new therapeutic agent for the treatment of numerous heart diseases.

Effects of garlic (Allium sativum L) and Citrullus colocynthis (L.) Schrad individually and in combination on male reproductive damage due to diabetes: suppression of the AGEs/RAGE/Nox-4 signaling pathway

BACKGROUND

Diabetes Mellitus is associated with disturbances in male reproductive function and fertility. Studies have shown that oxidative stress with the subsequent inflammation and apoptosis cause these complications in diabetes. Garlic (G) (Allium sativum L) and Citrullus colocynthis (L.) Schrad (C) both have antidiabetic and antioxidant properties. Recently, we demonstrated their synergistic effects in alleviating reproductive complications when administered concomitantly. However, as even medicinal plants in long term usage may lead to some unwanted side effects of their own, we examined whether with half the original doses of these two medicinal plants we could achieve the desired results.

METHODS

Thirty-five male Wistar rats were divided into five groups (n = 7/group): Control, Diabetic, Diabetic + G (0.5 ml/100 g BW), Diabetic + C (5 mg/kg BW) and Diabetic + GC (0.5 ml/100 g BW of garlic and 5 mg/kg BW of C. colocynthis) groups. The experimental period was 30 days.

RESULTS

Oxidative stress, advanced glycation end products (AGEs), immunoexpression of caspase-3, and expression of mRNAs for receptor for advanced glycation end products (RAGE), NADPH oxidase-4 (NOX-4) and nuclear factor kappa B increased in testis of diabetic rats. Treatment with garlic and C. colocynthis alone showed some beneficial effects, but in the combination form the effectiveness was more profound.

CONCLUSIONS

We conclude that the combination therapy of diabetic rats with lower doses is still as efficient as higher doses; therefore, the way forward for reducing complications in long term consumption.

Diallyl trisulfide (DATS) protects cardiac cells against advanced glycation end-product-induced apoptosis by enhancing FoxO3A-dependent upregulation of miRNA-210

Diabetic cardiomyopathy is a common complication of diabetes, resulting in cardiac hypertrophy and heart failure associated with excessive reactive oxygen species and mitochondria-mediated apoptosis generation. Mitogen-activated protein kinase-c-Jun N-terminal kinase (MAPK-JNK), regulated by microRNA (miR)-210, affects mitochondrial function and is activated by advanced glycation end-products (AGE) in cardiac cells. Diallyl trisulfide (DATS), an antioxidant in garlic oil, inhibits stress-induced cardiac apoptosis. This study examined whether DATS enhances miR-210 expression to attenuate cardiac apoptosis. We investigated the DATS-mediated attenuation mechanism of AGE-enhanced cardiac apoptosis by modulating miR-210 and its upstream transcriptional regulator, FoxO3a. We found FoxO3a binding sites in the miR-210 promoter region. Our results indicated that DATS treatment inhibited AGE-induced JNK activation, phosphoprotein c-Jun nuclear transactivation, and cardiac apoptosis and reversed the AGE-induced reduction in cardiac miR-210 levels. The luciferase activity after DATS treatment was significantly lower than that of the control and was reversed following AGE treatment. We also showed that FoxO3a, upregulated by DATS treatment, may bind to the miR-210 promoter to enhance its expression and downregulates JNK expression to attenuate AGE-induced cardiac apoptosis. Oral administration of DATS enhanced FoxO3a expression in the heart and reduced diabetes-induced heart apoptosis. Our findings indicate that DATS mediates AGE-induced cardiac cell apoptosis attenuation by promoting FoxO3a nuclear transactivation to enhance miR-210 expression and regulate JNK activation. Our results suggest that DATS can be used as a cardioprotective agent, and miR-210 is a critical regulator in inhibiting diabetic cardiomyopathy.

Characterization of volatile organic compounds with anti-atherosclerosis effects in Allium macrostemon Bge. and Allium chinense G. Don by head space solid phase microextraction coupled with gas chromatography tandem mass spectrometry

Introduction

Allium macrostemon Bge. (AMB) and Allium chinense G. Don (ACGD) are both edible Allium vegetables and named officinal Xiebai (or Allii Macrostemonis Bulbus) in East Asia. Their medicinal qualities involve in lipid lowering and anti-atherosclerosis effects. And steroidal saponins, nitrogenous compounds and sulfur compounds are like the beneficial components responsible for medicinal functions. Sulfur compounds are the recognized main components both in the volatile oils of AMB and ACGD. Besides, few researches were reported about their holistic chemical profiles of volatile organic compounds (VOCs) and pharmacodynamic effects.

Methods

In this study, we first investigated the lipid-lowering and anti-atherosclerotic effects of volatile oils derived from AMB and ACGD in ApoE ^-/- mice with high fat and high cholesterol diets.

Results

The results showed the volatile oils of AMB and ACGD both could markedly reduce serum levels of TG, TC, and LDL-C (p < 0.05), and had no alterations of HDL-C, ALT, and AST levels (p > 0.05). Pathological results displayed they both could obviously improve the morphology of cardiomyocytes and the degree of myocardial fibrosis in model mice. Meanwhile, oil red O staining results also proved they could apparently decrease the lesion areas of plaques in the aortic intima (p < 0.05). Furthermore, head space solid phase microextraction coupled with gas chromatography tandem mass spectrometry combined with metabolomics analysis was performed to characterize the VOCs profiles of AMB and ACGD, and screen their differential VOCs. A total of 121 and 115 VOCs were identified or tentatively characterized in the volatile oils of AMB and ACGD, respectively. Relative-quantification results also confirmed sulfur compounds, aldehydes, and heterocyclic compounds accounted for about 85.6% in AMB bulbs, while approximately 86.6% in ACGD bulbs were attributed to sulfur compounds, ketones, and heterocyclic compounds. Multivariate statistical analysis showed 62 differentially expressed VOCs were observed between AMB and ACGD, of which 17 sulfur compounds were found to be closely associated with the garlic flavor and efficacy.

Discussion

Taken together, this study was the first analysis of holistic chemical profiles and anti-atherosclerosis effects of AMB and ACGD volatile oils, and would benefit the understanding of effective components in AMB and ACGD.

How Does Allium Leafy Parts Metabolome Differ in Context to Edible or Inedible Taxa? Case Study in Seven Allium Species as Analyzed Using MS-Based Metabolomics

Genus Allium (F. Amaryllidaceae) includes a wide variety of edible foods widely consumed for their nutritive as well as health benefits. Seven Allium species, viz., chives, Egyptian leek, French leek, red garlic, white garlic, red onion, and white onion aerial parts were assessed for metabolome heterogeneity targeting both aroma and nutrients phytochemicals. A headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) were employed. Results revealed extensive variation in volatiles and nutrients profile among the seven Allium species represented by a total of 77 nutrients and 148 volatiles. Among edible Allium species, French leek encompassed high levels of nutrients, viz., sugars, fatty acids/esters, organic acids, and amino acids, compared to Egyptian leek. Sulfur aroma compounds appeared as the most discriminatory among Allium, taxa accounting for its distinct flavor. Furthermore, chemometric analysis of both datasets showed clear discrimination of the seven Allium species according to several key novel markers. This study provides the first comparative approach between edible and inedible aerial leafy parts of Allium species providing novel insight into their use as functional foods based on such holistic profiling.

Garlic (Allium sativum L.) in diabetes and its complications: Recent advances in mechanisms of action

Diabetes mellitus (DM) is a metabolic disease characterized by chronic hyperglycemia and impaired islet secretion that places a heavy burden on the global health care system due to its high incidence rate, long disease course and many complications. Fortunately, garlic (Allium sativum L.), a well-known medicinal plant and functional food without the toxicity and side effects of conventional drugs, has shown positive effects in the treatment of diabetes and its complications. With interdisciplinary development and in-depth exploration, we offer a clear and comprehensive summary of the research from the past ten years, focusing on the mechanisms and development processes of garlic in the treatment of diabetes and its complications, aiming to provide a new perspective for the treatment of diabetes and promote the efficient development of this field.

Synergistic properties of garlic and Citrullus colocynthis on reproductive injury caused by diabetes in male rats: Structural and molecular evidence

This study evaluates the synergistic effect of garlic and Citrullus colocynthis on diabetic reproductive damage by suppressing the AGEs/RAGE/Nox-4 signaling pathway. Thirty-five male Wistar rats were divided into five groups (n = 7/group): Control, Diabetic, Diabetic+G (Garlic, 1 mL/100 g b.w), Diabetic+C (C. colocynthis, 10 mg/kg b.w) and Diabetic+GC (Garlic, 1 mL/100 g b.w and C. colocynthis, 10 mg/kg b.w) groups. At the end of the experimental period (30 days), in diabetic rats, glucose increased, and body & testis weight, luteinizing hormone (LH) and testosterone levels, and sperm count decreased significantly and histopathological injuries were observed. In addition, they have increased testicular apoptosis and oxidative stress. Also, the mechanism based on advanced glycation end products (AGEs)/receptors for advanced glycation end products (RAGE)/NADPH oxidase-4 (Nox-4) was activated in diabetic rats. Separate consumption of garlic and C. colocynthis in Diabetic+G and Diabetic+C groups alleviated the negative adverse effect of diabetes to some extent, but when they were used in the combination form (Diabetic+GC) improvement was profound. Testis histopathology, increased body and testis weight, and enhanced capacity in protecting diabetic reproductive injury was seen. Decreases in testosterone and LH concentration and sperm count in diabetic rats were also reversed by combined administration of garlic and C. colocynthis. It regulated oxidative stress markers, meanwhile reducing caspase-3 immunoexpression. In addition, overexpression of RAGE, Nox-4 and nuclear transcription factor-κB (NF-κB) was inhibited by the combination of garlic and C. colocynthis. PRACTICAL APPLICATIONS: Diabetes mellitus is wide spread all around the world with variety of complications in body including reproductive system in which patients suffer from physical and psychological aspects. Despite many efforts in providing agents for controlling diabetes and its complications, economic conditions of some countries make it difficult for people to provide costly medicine and as a result, they have to bear the complications until they pass away. However, traditional medicine is still finding its way, especially in poor countries with emphasis on medicinal plants. There have been many studies on plants to alleviate diabetes or its side effects. But, using one plant for long term, may be not so effective. Here, we attempted to find whether two plants from two different species can show more efficacy than each one alone. We noticed garlic and Citrullus colocynthis despite having beneficial effects when used alone, they could show synergistic effects in combination.

Allicin and Capsaicin Ameliorated Hypercholesterolemia by Upregulating LDLR and Downregulating PCSK9 Expression in HepG2 Cells

Hypercholesterolemia is a common cause of cardiovascular diseases (CVDs). Although allicin and capsaicin possess hypolipidemic effects through several molecular mechanisms, their effects on LDLR and PCSK9 expression are still unknown. This study aimed to investigate the effects of allicin and capsaicin on LDLR and PCSK9 expression in HepG2 cells. The effects of allicin and capsaicin on cell viability were evaluated by MTT assay and trypan blue exclusion assay. Low-density lipoprotein receptor (LDLR) levels and LDL uptake were determined by flow cytometry and confocal laser scanning microscopy (CLSM), respectively. RT-qPCR and Western blot analyses were performed to evaluate the expression of PCSK9, LDLR, SREBP-2, and HNF1α. ELISA was used to measure PCSK9 levels in culture media. Allicin and capsaicin increased the protein expression levels of LDLR via activation of the transcription factor SREBP2. However, allicin and capsaicin decreased the expression of PCSK9 protein and the secretion of PCSK9 in culture media via the suppression of HNF1α. Moreover, allicin and capsaicin increased LDL uptake into HepG2 cells. The efficacies of the hypolipidemic effects of allicin (200 µM) and capsaicin (200 µM) were comparable to that of atorvastatin (10 µM) in this study. In conclusion, allicin and capsaicin possessed hypolipidemic effects via the upregulation of LDLR and downregulation of PCSK9 expression, thereby enhancing LDL uptake into HepG2 cells. This indicates that allicin and capsaicin should be used as potent supplements to ameliorate hypercholesterolemia.

Natural Products in Cardiovascular Diseases: The Potential of Plants from the Allioideae Subfamily (Ex-Alliaceae Family) and Their Sulphur-Containing Compounds

Cardiovascular diseases (CVDs) are the leading cause of mortality worldwide and, together with associated risk factors such as diabetes, hypertension, and dyslipidaemia, greatly impact patients' quality of life and health care systems. This burden can be alleviated by fomenting lifestyle modifications and/or resorting to pharmacological approaches. However, due to several side effects, current therapies show low patient compliance, thus compromising their efficacy and enforcing the need to develop more amenable preventive/therapeutic strategies. In this scenario, medicinal and aromatic plants are a potential source of new effective agents. Specifically, plants from the Allioideae subfamily (formerly Alliaceae family), particularly those from the genus Allium and Tulbaghia, have been extensively used in traditional medicine for the management of several CVDs and associated risk factors, mainly due to the presence of sulphur-containing compounds. Bearing in mind this potential, the present review aims to gather information on traditional uses ascribed to these genera and provide an updated compilation of in vitro and in vivo studies validating these claims as well as clinical trials carried out in the context of CVDs. Furthermore, the effect of isolated sulphur-containing compounds is presented, and whenever possible, the relation between composition and activity and the mechanisms underlying the beneficial effects are pointed out.

Biological Functions of Diallyl Disulfide, a Garlic-Derived Natural Organic Sulfur Compound

Garlic is widely accepted as a functional food and an excellent source of pharmacologically active ingredients. Diallyl disulfide (DADS), a major bioactive component of garlic, has several beneficial biological functions, including anti-inflammatory, antioxidant, antimicrobial, cardiovascular protective, neuroprotective, and anticancer activities. This review systematically evaluated the biological functions of DADS and discussed the underlying molecular mechanisms of these functions. We hope that this review provides guidance and insight into the current literature and enables future research and the development of DADS for intervention and treatment of multiple diseases.

Diallyl Trisulfide Suppresses High-Glucose-Induced Cardiomyocyte Apoptosis by Targeting Reactive Oxygen Species-Mediated Hypoxia-Inducible Factor-1α/Insulin-like Growth Factor Binding Protein 3 Activation

It has been reported that 80% of diabetic patients die due to cardiovascular diseases. We previously demonstrated that activated hypoxia-inducible factor-1α (HIF-1 α)/insulin-like growth factor binding protein-3 (IGFBP-3) signaling by reactive oxygen species (ROS)-regulated prolyl hydroxylase domain-containing protein (PHD) is involved in high-glucose (HG)-induced cardiac apoptosis. Diallyl trisulfide (DATS), a garlic component, shows the strongest inhibitory effect on diabetic cardiomyopathy. In this study, we investigated whether HIF-1α/IGFBP-3 signaling governs the antiapoptotic effect by DATS on HG-exposed cardiomyocytes. It was observed that significantly increased levels of cell apoptosis and decreased Akt phosphorylation were reversed by DATS in HG-exposed cardiac cells. H₂O₂ and PHD small interfering RNA treatments increased HIF-1α and IGFBP-3 protein levels, which were decreased by DATS treatment. Overexpression of HIF-1α and IGFBP-3 increased HG-induced cell apoptosis, which was suppressed by DATS. The coimmunoprecipitation assay results showed that DATS not only increased the IGF-1 level and reduced IGFBP-3 level but also suppressed their extracellular association for cardiac cells exposed to HG. Experiments using neonatal cardiomyocytes and hearts showed similar results. These findings indicate that the effect of ROS-regulated PHD on the activation of HIF-1α/IGFBP-3 signaling governs the antiapoptotic effect by DATS on HG-exposed cardiomyocytes.

E3 ligase activity of Carboxyl terminus of Hsc70 interacting protein (CHIP) in Wharton's jelly derived mesenchymal stem cells improves their persistence under hyperglycemic stress and promotes the prophylactic effects against diabetic cardiac damages

Recent studies indicate that umbilical cord stem cells are cytoprotective against several disorders. One critical limitation in using stem cells is reduction in their viability under stressful conditions, such as diabetes. However, the molecular intricacies responsible for diabetic conditions are not fully elucidated. In this study, we found that high glucose (HG) conditions induced loss of chaperone homeostasis, stabilized PTEN, triggered the downstream signaling cascade, and induced apoptosis and oxidative stress in Wharton's jelly derived mesenchymal stem cells (WJMSCs). Increased Carboxyl terminus of Hsc70 interacting protein (CHIP) expression promoted phosphatase and tensin homolog (PTEN) degradation via the ubiquitin-proteasome system and shortened its half-life during HG stress. Docking studies confirmed the interaction of CHIP with PTEN and FOXO3a with the Bim promoter region. Further, it was found that the chaperone system is involved in CHIP-mediated PTEN proteasomal degradation. CHIP depletion stabilizes PTEN whereas PTEN inhibition showed an inverse effect. CHIP overactivation suppressed the binding of FOXO3a with bim. Coculturing CHIP overexpressed WJMSCs suppressed HG-induced apoptosis and oxidative stress in embryo derived cardiac cell lines. CHIP overexpressing and PTEN silenced WJMSCs ameliorated diabetic effects in streptozotocin (STZ) induced diabetic rats and further improved their body weight and heart weight, and rescued from hyperglycemia-induced cardiac injury. Considering these, the current study suggests that CHIP confers resistance to apoptosis and acts as a potentiation factor in WJMSCs to provide protection from degenerative effects of diabetes.

Natural and synthetic antioxidants targeting cardiac oxidative stress and redox signaling in cardiometabolic diseases

Cardiometabolic diseases (CMDs) are metabolic diseases (e.g., obesity, diabetes, atherosclerosis, rare genetic metabolic diseases, etc.) associated with cardiac pathologies. Pathophysiology of most CMDs involves increased production of reactive oxygen species and impaired antioxidant defense systems, resulting in cardiac oxidative stress (OxS). To alleviate OxS, various antioxidants have been investigated in several diseases with conflicting results. Here we review the effect of CMDs on cardiac redox homeostasis, the role of OxS in cardiac pathologies, as well as experimental and clinical data on the therapeutic potential of natural antioxidants (including resveratrol, quercetin, curcumin, vitamins A, C, and E, coenzyme Q10, etc.), synthetic antioxidants (including N-acetylcysteine, SOD mimetics, mitoTEMPO, SkQ1, etc.), and promoters of antioxidant enzymes in CMDs. As no antioxidant indicated for the prevention and/or treatment of CMDs has reached the market despite the large number of preclinical and clinical studies, a sizeable translational gap is evident in this field. Thus, we also highlight potential underlying factors that may contribute to the failure of translation of antioxidant therapies in CMDs.

A comprehensive understanding about the pharmacological effect of diallyl disulfide other than its anti-carcinogenic activities

Diallyl disulfide (DADS), an oil-soluble sulfur compound that is responsible for the biological effects of garlic, displays numerous biological activities, among which its anti-cancer activities are the most famous ones. In recent years, the pharmacological effects of DADS other than its anti-carcinogenic activities have attracted numerous attentions. For example, it has been reported that DADS can prevent the microglia-mediated neuroinflammatory response and depression-like behaviors in mice. In the cardiovascular system, DADS administration was found to ameliorate the isoproterenol- or streptozotocin-induced cardiac dysfunction via the activation of the nuclear factor E2-related factor 2 (Nrf2) and insulin-like growth factor (IGF)-phosphatidylinositol-3-kinase (PI3K)-protein kinase B (Akt) signaling. DADS administration can also produce neuroprotective effects in animal models of Alzheimer's disease and protect the heart, endothelium, liver, lung, and kidney against cellular or tissue damages induced by various toxic factors, such as the oxidized-low density lipoprotein (ox-LDL), carbon tetrachloride (CCl₄), ethanol, acetaminophen, Cis-Diammine Dichloroplatinum (CisPt), and gentamicin. The major mechanisms of action of DADS in disease prevention and/or treatment include inhibition of inflammation, oxidative stress, and cellular apoptosis. Mechanisms, including the activation of Akt, extracellular signal-regulated kinase 1/2 (ERK1/2), protein kinase A (PKA), and cyclic adenosine monophosphate-response element binding protein (CREB) and the inhibition of histone deacetylases (HDACs), can also mediate the cellular protective effects of DADS in different tissues and organs. In this review, we summarize and discuss the pharmacological effects of DADS other than its anti-carcinogenic activities, aiming to reveal more possibilities for DADS in disease prevention and/or treatment.

Simvastatin protects high glucose-induced H9c2 cells from injury by inducing autophagy

CONTEXT

Simvastatin is the first line therapeutic drug for coronary heart disease and atherosclerosis. The protective effect mechanism of simvastatin on cardiomyocytes is unclear.

OBJECTIVE

This study explores the effect of simvastatin on high glucose induced cardiomyocyte injury and the role of autophagy during the process.

MATERIALS AND METHODS

H9c2 cells were incubated with different doses of glucose (0, 50, 100, 200 mM) for 24 h to verify the glucose induced injury. The H9c2 cells were pre-treated with simvastatin at different dosages (0, 0.1, 0.5, 1 μM) for 30 min to rescue the injury followed by the autophagy evaluation. 3-MA was used as an autophagy inhibitor to confirm the role of autophagy in simvastatin treated process. CCK-8 assay, FACS assay, confocal microscopy, western blotting and immunofluorescence analysis were conducted to evaluate the high glucose induced injury or protective effects of simvastatin in H9c2 cell line.

RESULTS

High glucose dramatically decreased H9c2 cell viability (0 mM, 0.58 ± 0.09%; vs. 50 mM, 8.67 ± 0.43%; 100 mM, 16.1 ± 3.56%; 200 mM, 32.9 ± 2.63%), induced significant cell apoptosis (0 mM, 0.96 ± 0.16%, vs. 50 mM, 7.00 ± 0.63%; 100 mM, 12.9 ± 0.78%; 200 mM, 21.8 ± 1.17%) and suppressed cell autophagy. Simvastatin decreased apoptosis and attenuate injury by decreasing cell apoptosis ratio, elevating Bcl-2 expression while decreasing Bax and caspase-3 protein expressions. Meanwhile, simvastatin restored the autophagy depicted by western blotting with increased ATG-5, Beclin1 and LC3II/LC3I protein expression and decreased p62 expression, as well as immunofluorescence with elevated LC3 fluorescence density.

DISCUSSION AND CONCLUSIONS

The myocardial protective effect mediated by autophagy activated by simvastatin to some extent elucidated the mechanism of the protective effect of simvastatin on H9c2 cell injury, which provided a certain theoretical basis for the clinical application of simvastatin in the treatment of cardiovascular diseases. In addition, we speculate that simvastatin may be used for diabetes associated cardiovascular diseases.

Nutraceutical Vegetable Oil Nanoformulations for Prevention and Management of Diseases

The scientific community is becoming increasingly interested in identifying, characterizing, and delivering nutraceuticals, which constitutes a multi-billion-dollar business. These bioactive agents are claimed to exhibit several health benefits, including the prevention and treatment of diseases such as arthritis, cancer, osteoporosis, cataracts, Alzheimer's, and Huntington's diseases, heart, brain and metabolic disorders, etc. Nutraceuticals are typically consumed as part of a regular human diet and are usually present within foods, comprising vegetable oil, although at low levels and variable composition. Thus, it is difficult to control the type, amount and frequency of their ingestion by individuals. Nanoformulations about vegetable oil-based bioactive compounds with nutraceutical properties are useful for overcoming these issues, while improving the uptake, absorption, and bioavailability in the body. The purpose of this current study is to review papers on such nanoformulations, particularly those relevant for health benefits and the prevention and management of diseases, as well as bioactives extracted from vegetable oils enhancing the drug effectiveness, retrieved through bibliographic databases by setting a timespan from January 2000 to April 2020 (about 1758 records).

Diallyl Trisulfide (DATS) Suppresses AGE-Induced Cardiomyocyte Apoptosis by Targeting ROS-Mediated PKCδ Activation

Chronic high-glucose exposure results in the production of advanced glycation end-products (AGEs) leading to reactive oxygen species (ROS) generation, which contributes to the development of diabetic cardiomyopathy. PKCδ activation leading to ROS production and mitochondrial dysfunction involved in AGE-induced cardiomyocyte apoptosis was reported in our previous study. Diallyl trisulfide (DATS) is a natural cytoprotective compound under various stress conditions. In this study, the cardioprotective effect of DATS against rat streptozotocin (STZ)-induced diabetic mellitus (DM) and AGE-induced H9c2 cardiomyoblast cell/neonatal rat ventricular myocyte (NRVM) damage was assessed. We observed that DATS treatment led to a dose-dependent increase in cell viability and decreased levels of ROS, inhibition of PKCδ activation, and recuded apoptosis-related proteins. Most importantly, DATS reduced PKCδ mitochondrial translocation induced by AGE. However, apoptosis was not inhibited by DATS in cells transfected with PKCδ-wild type (WT). Inhibition of PKCδ by PKCδ-kinase-deficient (KD) or rottlerin not only inhibited cardiac PKCδ activation but also attenuated cardiac cell apoptosis. Interestingly, overexpression of PKCδ-WT plasmids reversed the inhibitory effects of DATS on PKCδ activation and apoptosis in cardiac cells exposed to AGE, indicating that DATS may inhibit AGE-induced apoptosis by downregulating PKCδ activation. Similar results were observed in AGE-induced NRVM cells and STZ-treated DM rats following DATS administration. Taken together, our results suggested that DATS reduced AGE-induced cardiomyocyte apoptosis by eliminating ROS and downstream PKCδ signaling, suggesting that DATS has potential in diabetic cardiomyopathy (DCM) treatment.

The cardioprotective effects of diallyl trisulfide on diabetic rats with ex vivo induced ischemia/reperfusion injury

Diallyl trisulfide (DATS) is distinguished as the most potent polysulfide isolated from garlic. The aim of our study was to investigate effects of oral administration of DATS on healthy and diabetic rats, with special attention on heart function. Rats were randomly divided into four groups: CTRL (healthy rats), DATS (healthy rats treated with DATS), DM (diabetic rats), DM + DATS (diabetic rats treated with DATS). DATS (40 mg/kg of body weight) was administered every other day for 3 weeks, at the end of which rats underwent echocardiography, glycemic measurement and redox status assessment. Isolated rat hearts were subjected to 30 min global ischemia and 60 min reperfusion, after which heart tissue was counterstain with hematoxylin and eosin and cardiac Troponin T staining (cTnT), while expression of Bax, B cell lymphoma 2 (Bcl-2), caspase-3, caspase-9 and superoxide dismutase-2 were examined in the left ventricle. DATS treatment significantly reduced blood glucose levels of diabetic rats, and improved cardiac function recovery, diminished oxidation status, attenuated cardiac remodeling and inhibited myocardial apoptosis in healthy and diabetic rats. DATS treatment causes promising cardioprotective effects on ex vivo-induced ischemia/reperfusion (I/R) injury in diabetic and healthy rat heart probably mediated by inhibited myocardial apoptosis. Moreover, appropriate DATS consumption may provide potential co-therapy or prevention of hyperglycemia and various cardiac complications in rats with DM.

ROS- and HIF1α-dependent IGFBP3 upregulation blocks IGF1 survival signaling and thereby mediates high-glucose-induced cardiomyocyte apoptosis

The prevalence of chronic hyperglycemia and its complications, imposing a critical burden on the worldwide economy and the global healthcare system, is a pressing issue. Mounting evidence indicates that oxidative stress and hypoxia, two noticeable features of hyperglycemia, play a joint crucial role in mediating cellular apoptosis. However, the underlying detailed molecular mechanism remains elusive. Triggered by the observation that insulin-like growth factor (IGF1)-binding protein 3 (IGFBP3) can mediate, in renal cells, high-glucose-induced apoptosis by elevating oxidative stress, we wish to, in this study, know whether or not the similar scenario holds in cardiac cells and, if so, to find its relevant molecular key players, thereby dissecting the underlying molecular pathway. Specifically, we used a combination of three different cellular sources (H9c2 cells, diabetic rats, and neonatal rat ventricular cardiomyocytes) as our model systems of study. We made use of Co-IP assay and western blot analysis in conjunction with loss-of-function reasoning, gain-of-function logic, and inhibitor treatment as our main analytical tools. As a result, briefly, our main findings are that hyperglycemia can induce cardiac IGFBP3 overexpression and secretion, that high levels of IGFBP3 can sequester IGF1 from IGF1 survival pathway, leading to apoptosis, and that IGFBP3 gene upregulation is hypoxia-inducible factor (HIF)1α-dependent and reactive oxygen species dependent. Piecing these findings together allows us to propose the improved molecular regulatory mechanism. In conclusion, we have established the molecular roles of IGFBP3, HIF1, and prolyl hydroxylase domain in connecting oxidative stress with hypoxia and in cellular apoptosis under hyperglycemia.

Anti-obesity and Hypolipidemic effects of garlic oil and onion oil in rats fed a high-fat diet

Background

Until now, little research concerning the lipid-lowering and anti-obesity functions of garlic oil and onion oil has been performed. The objective of this study was to explore the effects of garlic oil and onion oil on serum lipid levels in hyperlipidemia model rats, to provide a scientific basis for the prevention of hyperlipidemia through a dietary approach, and to explore the potential health benefits of garlic and onion.

Method

Ninety-six male Sprague-Dawley rats were randomly allocated into eight groups based on their body weight and serum levels of triglycerides (TG) and total cholesterol (TC). The rats received repeated oral administration of volatile oils extracted from garlic and onion for 60 days. Serum lipids and parameters of obesity were examined.

Results

The volatile oils suppressed the HFD-induced body weight gain and tended to decrease adipose tissue weight. The oils decreased the levels of TG, TC and LDL-C and increased the serum level of HDL-C compared with the rats in the hyperlipidemia model groups (P < 0.05). The oils were also effective at improving the lipid profile and alleviating hepatic steatosis.

Conclusion

Our results implied that garlic oil and onion oil have anti-obesity properties that can counteract the effects of an HFD on body weight, adipose tissue weight, and serum lipid profiles.

Electronic supplementary material

The online version of this article (10.1186/s12986-018-0275-x) contains supplementary material, which is available to authorized users.

Diallyl trisulfide ameliorates myocardial ischemia-reperfusion injury by reducing oxidative stress and endoplasmic reticulum stress-mediated apoptosis in type 1 diabetic rats: role of SIRT1 activation

Diallyl trisulfide (DATS) protects against apoptosis during myocardial ischemia-reperfusion (MI/R) injury in diabetic state, although the underlying mechanisms remain poorly defined. Previously, we and others demonstrated that silent information regulator 1 (SIRT1) activation inhibited oxidative stress and endoplasmic reticulum (ER) stress during MI/R injury. We hypothesize that DATS reduces diabetic MI/R injury by activating SIRT1 signaling. Streptozotocin (STZ)-induced type 1 diabetic rats were subjected to MI/R surgery with or without perioperative administration of DATS (40 mg/kg). We found that DATS treatment markedly improved left ventricular systolic pressure and the first derivative of left ventricular pressure, reduced myocardial infarct size as well as serum creatine kinase and lactate dehydrogenase activities. Furthermore, the myocardial apoptosis was also suppressed by DATS as evidenced by reduced apoptotic index and cleaved caspase-3 expression. However, these effects were abolished by EX527 (the inhibitor of SIRT1 signaling, 5 mg/kg). We further found that DATS effectively upregulated SIRT1 expression and its nuclear distribution. Additionally, PERK/eIF2α/ATF4/CHOP-mediated ER stress-induced apoptosis was suppressed by DATS treatment. Moreover, DATS significantly activated Nrf-2/HO-1 antioxidant signaling pathway, thus reducing Nox-2/4 expressions. However, the ameliorative effects of DATS on oxidative stress and ER stress-mediated myocardial apoptosis were inhibited by EX527 administration. Taken together, these data suggest that perioperative DATS treatment effectively ameliorates MI/R injury in type 1 diabetic setting by enhancing cardiac SIRT1 signaling. SIRT1 activation not only upregulated Nrf-2/HO-1-mediated antioxidant signaling pathway but also suppressed PERK/eIF2α/ATF4/CHOP-mediated ER stress level, thus reducing myocardial apoptosis and eventually preserving cardiac function.

Synergistic effect of HIF-1α and FoxO3a trigger cardiomyocyte apoptosis under hyperglycemic ischemia condition

Cardiomyocyte death is an important pathogenic feature of ischemia and heart failure. Through this study, we showed the synergistic role of HIF-1α and FoxO3a in cardiomyocyte apoptosis subjected to hypoxia plus elevated glucose levels. Using gene specific small interfering RNAs (siRNA), semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR), Western blot, immunofluorescence, nuclear and cytosolic localization and TUNEL assay techniques, we determined that combined function of HIF-1α and FoxO3a under high glucose plus hypoxia condition lead to enhanced expression of BNIP3 inducing cardiomyocyte death. Our results highlighted the importance of the synergistic role of HIF-1α and FoxO3a in cardiomyocyte death which may add insight into therapeutic approaches to pathophysiology associated with ischemic diabetic cardiomyopathies.

Green tea epigallocatechin gallate enhances cardiac function restoration through survival signaling expression in diabetes mellitus rats with autologous adipose tissue-derived stem cells

The present study tests a hypothesis that cardioprotective effects mediated by autologous adipose-derived stem cells (ADSC) in rats afflicted with insulin-dependent diabetes mellitus (IDDM) may be synergistically enhanced by oral treatment with green tea epigallocatechin gallate (EGCG). Wistar rats were divided into sham, DM, DM+ADSC (autologous transplanted 1 × 106 cells per rat), and DM+ADSC+E (E, green tea oral administration EGCG). Heart tissues were isolated from all rats, and investigations were performed after 2-mo treatment. In the sham, DM, and DM+ADSC groups, we found that DM induced cardiac dysfunction (sham and DM) and autologous ADSC transplantation could partially recover cardiac functions (DM and DM+ADSC) in DM rats. Compared with DM+ADSC, significant improvement in cardiac functions can be observed in DM+ADSC+E in echocardiographic data, histological observations, and even cellular protein expression. Oral green tea EGCG administration and autologous ADSC transplantation show synergistically beneficial effects on diabetic cardiac myopathy in DM rats.

NEW & NOTEWORTHY Cardiomyopathy can be induced in rats with diabetes mellitus (DM). Heart function can be restored in DM rats with adipose-derived stem cell treatment. Oral epigallocatechin gallate (EGCG) administration synergistically enhances cardiac function in DM rats with stem cell treatment. The EGCG and stem cell treatment cross-effect occurs via survival protein expression.

Evaluation of garlic oil in nano-emulsified form: Optimization and its efficacy in high-fat diet induced dyslipidemia in Wistar rats

Garlic oil nanoemulsion was formulated using ultrasonic emulsification and the optimized garlic oil nanoemulsion ratio (1:2) of oil: surfactant showed spherical, with tiny droplet size 24.9 ± 1.11 nm. It was observed that the prepared nanoemulsion has the zeta potential of -42.63 ± 1.58 mV and a low polydispersity index of 0.2 ± 0.09 with excellent stability. The formulation was subjected to in vivo acute and sub-acute toxicity. In acute toxicity study, single oral administration of 18.63 ml of garlic oil nanoemulsion/kg resulted in immediate mortality. However, garlic oil nanoemulsion (0.46 ml/kg) and tween 80 (0.5 ml/kg) administered rats did not exhibit any toxicity and showed no changes in hematological and histological parameters. Further, both preventive and curative studies of garlic oil nanoemulsion were evaluated in high-fat diet fed dyslipidemic Wistar rats. Garlic oil nanoemulsion administered groups showed a significant effect in reducing the levels of lipid profiles (p < 0.001) compared to atorvastatin and garlic oil. Evaluation of lipid deposits in hepatic tissues was analyzed by Oil Red O staining, which revealed that garlic oil nanoemulsion administered rats markedly reduced the fat depots. Our findings suggest that garlic oil nano-emulsified form reduced toxicity and improved efficacy in preventing and treating dyslipidemia.

Cytoprotective effects of diallyl trisulfide against valproate-induced hepatotoxicity: new anticonvulsant strategy

Sodium valproate (VP) is an important antiepileptic drug, although it can produce deleterious hepatotoxic reactions. Diallyl trisulfide (DATS) is the principle component of garlic oil that possesses antioxidant properties. This study explored the potential hepatoprotective activity of DATS against VP-induced hepatic damage and its underlying mechanisms. In addition, the study assessed the effect of DATS on VP antiepileptic activity. Rats were given DATS once daily at two different doses along with VP for 2 weeks. Results have shown the ability of DATS to counteract VP-induced hepatic damage as it decreased elevated serum transaminases (aspartate aminotransferase and alanine aminotransferase) and alkaline phosphatase. Liver histopathology indicated that DATS preserved the hepatic structural integrity and protected against VP-induced hepatic steatosis and necro-inflammation injury. DATS ameliorated VP-induced oxidative stress and increased the antioxidant capacity of the liver. Immunohistochemical analysis showed activation of nuclear factor kappa-B along with high expression of cyclo-oxygenase-2 (COX-2) upon VP administration. This was accompanied by overproduction of proinflammatory mediators (TNF-α, IL-1β, IL-6). Tracing the apoptotic pathway, VP administration induced marked apoptosis using TUNEL staining. Furthermore, VP-treated animals exhibited high immunoexpression of Bax protein and increased levels of Bax and caspase-3 while level of Bcl2 was significantly decreased in hepatic tissue. However, DATS simultaneous treatment counteracted all of these molecular pathological changes. Using pentylenetetrazole (PTZ)-induced seizures model in mice, the effect of DATS on the anticonvulsant activity of VP was found to be positive, meaning that combination of DATS with VP can confer protection against VP-induced hepatic injurious effects through its antioxidant, antiinflammatory, and antiapoptotic properties without affecting VP antiepileptic activity.

Diabetes mellitus and its management with medicinal plants: A perspective based on Iranian research

ETHNOPHARMACOLOGICAL RELEVANCE

Complementary and alternative medicine has been increasingly used to treat chronic illnesses, such as diabetes mellitus. However, various limitations in terms of their application and efficacies exist. Furthermore, there is still much to be done to discover the right herbal medicine for diabetes.

AIM OF THE STUDY

This paper aims to evaluate previous herbal studies on the management of diabetes mellitus, to address their strengths and weaknesses and propose a general framework for future studies.

APPROACH AND METHODS

Data sources such as PubMed, ScienceDirect, Scopus, SpringerLink, and Wiley were searched, limited to Iran, using 36 search terms such as herbal, traditional, medicine, and phytopharmacy in combination with diabetes and related complications. Reviewed articles were evaluated regarding the use of botanical nomenclature and included information on (1) identity of plants and plant parts used, (2) the processing procedure, and (3) the extraction process. The main outcomes were extracted and then surveyed in terms of the efficacies of herbs in the management of diabetes mellitus. Then a comparative study was performed between Iranian and non-Iranian studies with respect to herbs best studied in Iran.

RESULTS

Of the 82 herbs studied in Iran, only six herbs were endemic and 19 were studied in detail. Although most of the reviewed herbs were found to decrease the level of blood glucose (BG) and/or glycated hemoglobin (HbA1C) in both Iranian and non-Iranian studies, information on their pharmacological mechanisms is scarce. However, the level of HbA1C was measured in a limited number of clinical trials or animal studies. Available information on both short- and long-term use of studied herbs on diabetes related complications and functions of involved organs as well as comorbid depression and/or simultaneous changes in lifestyle is also insufficient. Furthermore, little or no information on their phytochemical, toxicological, and herb-drug interaction properties is available. It is worth noting that the efficacy of the reviewed herbs has been studied scarcely in both humans and animals regarding both Iranian and non-Iranian studies. A significant number of reviewed articles failed to cite the scientific name of herbs and include information on the processing procedure and the extraction process.

CONCLUSIONS

Treatment of diabetes mellitus as a multifactorial disease using herbal medicines requires a comprehensive approach. In order to discover the right herbal medicine for the management of diabetes many other important factors than the levels of BG, HbA1C and insulin should be considered. According to our criteria, all the reviewed herbs suffered from inadequate investigation in human, animal and in vitro models in this respect, whereas they are worth investigating further. However, more research on endemic plants and the traditional history of herbal medicine is warranted. In our opinion, the pharmacological, toxicological, and phytochemical information should be obtained before clinical trials. Furthermore, information such as botanical scientific nomenclature, side effects, and toxicity will improve the quality and validity of publications in herbal research. In particular, designing a database covering all valid information about herbs and/or diseases will decrease unnecessary costs and increase the efficiency of research.

Diallyl trisulfide protects against high glucose-induced cardiac apoptosis by stimulating the production of cystathionine gamma-lyase-derived hydrogen sulfide

BACKGROUND

Cystathionine-γ-lyase (CSE)-derived hydrogen sulfide (H2S) is a potent cardioprotective agent. We investigated the effects of diallyl trisulfide (DATS) on CSE expression and H2S generation in myocardium and examined whether DATS-mediated H2S generation effectively protects rat heart from diabetes-induced cardiac damage.

METHODS

The correlations between the effects of hyperglycemia and diabetes on CSE expression and the effects of DATS and H2S on hyperglycemia and diabetes were examined in vitro in the cardiomyocyte cell line H9c2 and in vivo in hearts from rats with streptozotocin-induced diabetes mellitus (DM).

RESULTS

Expression of CSE, a catalyst of H2S production, was suppressed in H9c2 cells treated with high glucose (33 mM) and in DM rat hearts. CSE suppression also correlated with a decrease in the activation of the pro-survival protein kinase Akt. Treatment of H9c2 cells with DATS resulted in increased CSE expression and a reduction in apoptosis via a mechanism involving IGF1R/pAkt signaling and by modulating the expression of reactive oxygen species-related enzymes. The role CSE plays in the cardioprotective effects of DATS was further confirmed by CSE inhibition assays including inhibitors and siRNA.

CONCLUSION

DATS produces H2S as efficiently as NaSH and DATS-derived H2S provides effective cardioprotection. Further, our data indicate that H2S plays a major role in the protective effect of DATS against apoptosis of cardiomyocytes.

Chemical and biochemical mechanisms underlying the cardioprotective roles of dietary organopolysulfides

Foods that are rich in organosulfides are highly regarded for their broad range of functions in disease prevention and health promotion since ancient time yet modern scientific study, particularly clinical studies could not agree with traditional wisdom. One of the complexities is due to the labile nature of organosulfides, which are often transformed to different structures depending on the processing conditions. The recent evidence on polysulfides as H₂S donors may open up a new avenue for establishing structure and health promotion activity relationship. To put this development into perspective, we carried out a review on the recent progress on the chemistry and biochemistry of organopolysulfides with emphasis on their cardioprotective property. First, we briefly surveyed the foods that are rich in polysulfides and their structural diversity. This is followed by in-depth discussion on the chemical transformations of polysulfides under various processing conditions. We further reviewed the potential action mechanisms of polysulfides in cardioprotection through: (a) hydrogen sulfide releasing activity; (b) radical scavenging activity; and (c) activity in enzyme inhibition and intervention of gene regulation pathways. Based on the literature trend, we can conclude that the emerging concept of organopolysulfides as naturally occurring H₂S donors is intriguing and warrants further research to establish the structure and activity relationship of the organopolysulfides as H₂S donors.

Impact of the uremic milieu on the osteogenic potential of mesenchymal stem cells

Human mesenchymal stem cells (hMSCs), the precursors of osteoblasts during osteogenesis, play a role in the balance of bone formation and resorption, but their functioning in uremia has not been well defined. To study the effects of the uremic milieu on osteogenic properties, we applied an in vitro assay culturing hMSCs in osteogenic medium supplemented with serum from healthy donors and from uremic patients on hemodialysis. Compared to control, serum from uremic patients induces, in hMSC cultures, a modification of several key regulators of bone remodeling, in particular a reduction of the ratio Receptor Activator of Nuclear factor Kappa B Receptor (RANKL) over osteoprotegerin, indicating an adaptive response of the system to favor osteogenesis over osteoclastosis. However, the levels of osteopontin, osteocalcin, and collagen type I, are increased in cell medium, while BMP-2, and alizarin red staining were decreased, pointing to a reduction of bone formation favoring resorption. Selected uremic toxins, such as p-cresylsulfate, p-cresylglucuronide, parathyroid hormone, indoxyl sulfate, asymmetric dimethylarginine, homocysteine, were able to mimic some of the effects of whole serum from uremic patients. Serum from cinacalcet-treated patients antagonizes these effects. Hydrogen sulfide (H2S) donors as well as hemodialysis treatment are able to induce beneficial effects. In conclusion, bone modifications in uremia are influenced by the capability of the uremic milieu to alter hMSC osteogenic differentiation. Cinacalcet, H2S donors and a hemodialysis session can ameliorate the hampered calcium deposition.

Redox regulation of endothelial cell fate

Endothelial cells (ECs) are present throughout blood vessels and have variable roles in both physiological and pathological settings. EC fate is altered and regulated by several key factors in physiological or pathological conditions. Reactive nitrogen species and reactive oxygen species derived from NAD(P)H oxidases, mitochondria, or nitric oxide-producing enzymes are not only cytotoxic but also compose a signaling network in the redox system. The formation, actions, key molecular interactions, and physiological and pathological relevance of redox signals in ECs remain unclear. We review the identities, sources, and biological actions of oxidants and reductants produced during EC function or dysfunction. Further, we discuss how ECs shape key redox sensors and examine the biological functions, transcriptional responses, and post-translational modifications evoked by the redox system in ECs. We summarize recent findings regarding the mechanisms by which redox signals regulate the fate of ECs and address the outcome of altered EC fate in health and disease. Future studies will examine if the redox biology of ECs can be targeted in pathophysiological conditions.

Organosulfur garlic compounds induce neovasculogenesis in human endothelial progenitor cells through a modulation of MicroRNA 221 and the PI3-K/Akt signaling pathways

Human endothelial progenitor cells (EPCs) play crucial roles in the prevention of ischemic injury via neovasculogenesis. Frequent garlic consumption is reportedly associated with a low incidence of cardiovascular diseases (CVD). However, the molecular mechanisms by which garlic extracts, including diallyl disulfide (DADS) and diallyl trisulfide (DATS), exert an effect on neovasculogenesis have not been elucidated yet. The current study investigated the effects of these organosulfur compounds on neovasculogenesis by using vascular tube formation assay, Western blotting assay, real-time polymerase chain reaction (RT-PCR), and immunohistochemical (IHC) staining assays in both in vitro and in vivo models. The current study demonstrates that DADS and DATS dose-dependently enhance the neovasculogenesis of human EPCs in vitro. The mechanism of actions included the up-regulation of the c-kit protein, as well as the phosphorylation (i.e., activation) of the Akt and ERK 1/2 signaling molecules in human EPCs. Furthermore, DATS suppressed the expression of microRNA (miR) 221 in vitro. In a mouse xenograft model of neovasculogenesis, DATS consumption induced the formation of new blood vessels at a dosage of 10 mg/kg of body weight/day. It is suggested that garlic consumption enhances neovasculogenesis in human EPCs and thereby probably exerts a preventive effect against ischemic injuries.

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.