Antidiabetic role of a novel protein from garlic via NO in expression of Glut-4/insulin in liver of alloxan induced diabetic mice

Two novel angiotensin I-converting enzyme inhibitory peptides from garlic protein: In silico screening, stability, antihypertensive effects in vivo and underlying mechanisms

This study aimed to screen novel angiotensin I-converting enzyme (ACE) inhibitory peptides from garlic proteins and to explore their underlying antihypertensive mechanisms in vivo. After simulated hydrolysis and in silico screening, two novel peptides (MGR and HDCF) were obtained with the highest ACE inhibitory activity (IC50 of 4.50 μM and 26.38 μM) and acted as competitive inhibitors. They interacted with key residues in the ACE receptor mainly through hydrogen bonding and exhibited excellent stability against high temperature, extreme pH, and gastrointestinal digestion. In spontaneously hypertensive rats, MGR and HDCF effectively lowered blood pressure after single or continuous treatments. This was mainly achieved by balancing the renin-angiotensin system, improving renal and cardiac impairment, and regulating endothelial dysfunction. These findings suggested that garlic proteins were potentially suitable materials to prepare ACE inhibitory peptides and provided two promising candidates for ACE inhibition as functional food ingredients.

Hepatic insulin synthesis increases in rat models of diabetes mellitus type 1 and 2 differently

Insulin-positive (+) cells (IPCs), detected in multiple organs, are of great interest as a probable alternative to ameliorate pancreatic beta-cells dysfunction and insulin deficiency in diabetes. Liver is a potential source of IPCs due to it common embryological origin with pancreas. We previously demonstrated the presence of IPCs in the liver of healthy and diabetic rats, but detailed description and analysis of the factors, which potentially can induced ectopic hepatic expression of insulin in type 1 (T1D) and type 2 diabetes (T2D), were not performed. In present study we evaluate mass of hepatic IPCs in the rat models of T1D and T2D and discuss factors, which may stimulate it generation: glycaemia, organ injury, involving of hepatic stem/progenitor cell compartment, expression of transcription factors and inflammation. Quantity of IPCs in the liver was up by 1.7-fold in rats with T1D and 10-fold in T2D compared to non-diabetic (ND) rats. We concluded that ectopic hepatic expression of insulin gene is activated by combined action of a number of factors, with inflammation playing a decision role.

Influence of Garlic on the Glycemic Control and Lipid Profile in Animals with Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

Nonalcoholic fatty liver disease is the hepatic sign of metabolic syndrome. Here, we aimed to assess the effects of garlic and its major components on fasting plasma glucose, fasting insulin, and lipid profile levels in animal models of nonalcoholic fatty liver disease. A systematic search in PubMed, Scopus, ProQuest, and Web of Science was performed. After the screening process and data extraction, the pooled effect sizes were estimated using a random-effect model and stated as standardized mean differences and a 95% confidence interval. Out of 839 reports, 22 articles were included in the present study. The pooled results revealed that garlic and its components significantly decreased fasting plasma glucose (standardized mean difference: - 0.77, 95% confidence interval: - 1.42 to - 0.12, I2 : 58.85%), fasting insulin (standardized mean difference: - 1.88, 95% confidence interval: - 3.07 to - 0.69, I2 : 70.42%), serum triglyceride (standardized mean difference: - 1.01, 95% confidence interval: - 1.43 to - 0.59, I2 : 61.41%), cholesterol (standardized mean difference: - 1.00, 95% confidence interval: - 1.39 to - 0.60, I2 : 52.12%), and low-density lipoprotein cholesterol (standardized mean difference: - 0.98, 95% CI: - 1.63 to - 0.32, I2 : 71.58%) and increased high-density lipoprotein cholesterol (standardized mean difference: 1.05, 95% confidence interval: 0.52 to 1.58, I2 : 59.39%) levels. The type of animal, nonalcoholic fatty liver disease induction model, kind and duration of intervention, study model, and risk of bias were detected as possible sources of heterogeneity across studies. We conclude that garlic and its major components have a favorable impact on glycemic control and lipid profile in diet-induced nonalcoholic fatty liver disease animal models.

Nutraceutical management of metabolic syndrome as a palliative and a therapeutic to coronavirus disease (COVID) crisis

The global market for medicinal plants and herbs is on the increase due to their desirability, efficacy, and less adverse effects as complementary and alternative medications to the orthodox pharmaceuticals, perhaps due to their natural components and qualities. Metabolic syndromes are managed with changes in diet, exercise, lifestyle modifications and the use of pharmacological agents. Plants are now known to have potent antioxidant and cholinergic activities which are relevant to the management of several metabolic syndromes, which are unfortunately, co-morbidity factors in the coronavirus disease crisis. This review will focus on the biological activities of some plant products used as complementary and alternative medicines in the management of metabolic syndromes, and on their reported antiviral, antithrombotic, angiotensin-converting enzyme inhibitory properties, which are integral to their usage in the management of viral infections and may give an avenue for prophylactic and therapeutics especially in the absence of vaccines/formulated antiviral therapies.

A review on the effect of garlic on diabetes, BDNF, and VEGF as a potential treatment for diabetic retinopathy

BACKGROUND

Garlic is one of the favorite herbs in traditional medicine that has been reported to have many medicinal features. The aim of the current study is to review the latest documents on the effect of garlic on diabetes, VEGF, and BDNF and, finally, to review the existing studies on the effect of garlic on diabetic retinopathy.

MAIN TEXT

The therapeutic effect of garlic on diabetes has been investigated in various studies. Diabetes, especially in advanced stages, is associated with complications such as diabetic retinopathy, which is caused by the alteration in the expression of molecular factors involved in angiogenesis, neurodegeneration, and inflammation in the retina. There are different in-vitro and in-vivo reports on the effect of garlic on each of these processes. Considering the present concept, we extracted the most related English articles from Web of Science, PubMed, and Scopus English databases from 1980 to 2022. All in-vitro and animal studies, clinical trials, research studies, and review articles in this area were assessed and classified.

RESULT AND CONCLUSION

According to previous studies, garlic has been confirmed to have beneficial antidiabetic, antiangiogenesis, and neuroprotective effects. Along with the available clinical evidence, it seems that garlic can be suggested as a complementary treatment option alongside common treatments for patients with diabetic retinopathy. However, more detailed clinical studies are needed in this field.

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.

The levels of nitrite, nitrate and lipid peroxidation in diabetic mouse brain: the effect of melatonin and pentoxifylline

OBJECTIVE

This study investigated the relationship between diabetes (DM) and nitrite, nitrate and MDA levels and effect of melatonin and pentoxifylline.

METHODS

Sixty mice were randomly divided into four groups. Control: no action; Diabetes group (DM): after fasting-blood-glucose (FBG) was measured, 150 mg/kg alloxane was applied intraperitoneally three-times every other day; Diabetes + Melatonin (DM + MLT) and Diabetes + Pentoxifylline groups (DM + PTX): following the same procedures with DM, 10 mg/kg melatonin and 50 mg/kg pentoxifylline were administered subcutaneously six days, respectively. Following FBG analysis, brain tissues were taken under the anaesthesia. Nitrite, nitrate and MDA levels were measured.

RESULTS

In the all groups with alloxane, FBG were higher than in before application (p < .05). Also, FBG, nitrite, nitrate and MDA levels in the DM + MLT and DM + PTX groups were lower than in the DM (p < .05).

CONCLUSIONS

Nitrite and nitrate may be related to etiopathogenesis of DM, and pentoxifylline and especially melatonin relatively decrease nitrite, nitrate and lipid peroxidation.

Comorbidity of osteoporosis and Alzheimer's disease: Is `AKT `-ing on cellular glucose uptake the missing link?

Osteoporosis and Alzheimer's disease (AD) are both degenerative diseases. Osteoporosis often proceeds cognitive deficits, and multiple studies have revealed common triggers that lead to energy deficits in brain and bone. Risk factors for osteoporosis and AD, such as obesity, type 2 diabetes, aging, chemotherapy, vitamin deficiency, alcohol abuse, and apolipoprotein Eε4 and/or Il-6 gene variants, reduce cellular glucose uptake, and protective factors, such as estrogen, insulin, exercise, mammalian target of rapamycin inhibitors, hydrogen sulfide, and most phytochemicals, increase uptake. Glucose uptake is a fine-tuned process that depends on an abundance of glucose transporters (Gluts) on the cell surface. Gluts are stored in vesicles under the plasma membrane, and protective factors cause these vesicles to fuse with the membrane, resulting in presentation of Gluts on the cell surface. This translocation depends mainly on AKT kinase signaling and can be affected by a range of factors. Reduced AKT kinase signaling results in intracellular glucose deprivation, which causes endoplasmic reticulum stress and iron depletion, leading to activation of HIF-1α, the transcription factor necessary for higher Glut expression. The link between diseases and aging is a topic of growing interest. Here, we show that diseases that affect the same biochemical pathways tend to co-occur, which may explain why osteoporosis and/or diabetes are often associated with AD.

Collagen/Chitosan Gels Cross-Linked with Genipin for Wound Healing in Mice with Induced Diabetes

Diabetes mellitus continues to be one of the most common diseases often associated with diabetic ulcers. Chitosan is an attractive biopolymer for wound healing due to its biodegradability, biocompatibility, mucoadhesiveness, low toxicity, and hemostatic effect. A panel of hydrogels based on chitosan, collagen, and silver nanoparticels were produced to treat diabetic wounds. The antibacterial activity, cytotoxicity, swelling, rheological properties, and longitudinal sections of hydrogels were studied. The ability of the gels for wound healing was studied in CD1 mice with alloxan-induced diabetes. Application of the gels resulted in an increase in VEGF, TGF-b1, IL-1b, and TIMP1 gene expression and earlier wound closure in a comparison with control untreated wounds. All gels increased collagen deposition, hair follicle repair, and sebaceous glands formation. The results of these tests show that the obtained hydrogels have good mechanical properties and biological activity and have potential applications in the field of wound healing. However, clinical studies are required to compare the efficacy of the gels as animal models do not reproduce full diabetes pathology.

From the distinctive smell to therapeutic effects: Garlic for cardiovascular, hepatic, gut, diabetes and chronic kidney disease

Garlic, a member of the Allium family, widely used in cooking for many centuries, displays well described antioxidant and anti-inflammatory properties, as a result of its constituent organosulfur compounds, such as alliin, allicin, ajoene S-allyl-cysteine, diallyl sulfide and diallyl disulfide, among others. Although garlic has demonstrated beneficial effects in cardiovascular disease, diabetes, and cancer, its efficacy as a therapeutic intervention in chronic kidney disease remains to be proven. This review thus focuses on the potential benefits of garlic as a treatment option in chronic kidney disease. and its ability to mitigate associated cardiovascular complications and gut dysbiosis.

Herbal Medicines for Diabetes Management and its Secondary Complications

Diabetic Mellitus (DM) is a metabolic disorder that is concerning for people all over the world. DM is caused due to lack of insulin or ineffective production of insulin in the pancreas. A total of 463 million people were reported to have diabetes mellitus in 2019 and this number is predicted to rise up to 578 million by the year 2030 and 700 million by 2045. High blood sugar gives rise to many complications like diabetic retinopathy, diabetic nephropathy, atherosclerosis, hypercoagulability, cardiovascular disease, coronary heart disease, abdominal obesity, hypertension, hyperlipidemia, cerebrovascular disease, coronary artery disease, foot damage, skin complications, Alzheimer's disease, hearing impairment, and depression. These life-threatening complications make diabetes more severe than other diseases. Many synthetic drugs have been developed, but still, a complete cure is not provided by any of the molecules. Continuous use of some synthetic agents causes severe side effects, and thus the demand for non-toxic, affordable drugs still persists. Traditional treatments have been an extremely valued source of medicine all over human history. These are extensively used throughout the world, indicating that herbs are a growing part of modern and high-tech medicines. The World Health Organization (WHO) has listed a total of 21,000 plants, which are used for medicinal purposes around the world. Among them, more than 400 plants are available for the treatment of diabetes. Despite the fact that there are many herbal drugs available for treating diabetes, only a small number of these plants have undergone scientific and medical evaluation to assess their efficacy. Trigonella foenum-graecum, Allium sativum, Caesalpinia bonduc, Ferula assafoetida,etc., are some of the medicinal plants used for antidiabetic therapy. The presence of phenolic compounds, flavonoids, terpenoids, and coumarins is responsible for the antidiabetic nature of the medicinal plants. These constituents have shown a reduction in blood glucose levels. Pycnogenol, acarbose, miglitol, and voglibose are some of the examples of marketed drugs, which are obtained from natural origin and used as antidiabetic drugs. The active principles derived from the plants work through many antidiabetic mechanisms, which include inhibition of α-glucosidase, α-amylase, and protein tyrosine phosphatase 1B activities. One of the major advantages of herbal drugs is the low level of side effects attributed to these medicines, and this attracted various researchers to develop new molecules for the treatment of diabetes. In this review, recent advances in the field of herbal drugs to treat diabetes, prevent secondary complications from arising due to diabetes, and various herbal molecules in different stages of clinical trials will be emphasized upon.

Protective effects of diallyl trisulfide (DATS) against doxorubicin-induced inflammation and oxidative stress in the brain of rats

Doxorubicin (DOX) is a widely used antitumor drug that causes severe neurotoxicity in patients. Diallyl trisulfide (DATS) is an organosulfur compound with established potent antioxidant and anti-inflammatory properties. Herein, we investigated the neuroprotective efficacy of DATS in preventing DOX-induced neurotoxicity in a rat model. Specifically, DATS (40 mg/kg) was administered to rats 24 h after DOX treatment, once a week for 8 weeks. Our results showed that DATS treatment led to a decrease in plasma levels of tumor necrosis factor-alpha (TNF-α) induced by DOX. DATS restored cerebral cortex and hippocampus histopathological architecture and neuronal loss. Immunohistochemical staining indicated that DATS decreased the expression of glial fibrillar acidic protein (GFAP) in DOX treated rats. Components of stress-related inflammatory proteins (TNF-α, phospho nuclear factor kappa B (NF-κB), inducible nitricoxide synthase (iNOS) and cyclooxygenase-2 (COX-2)) were all significantly increased in the DOX group, in comparison with the control group, whereas they were decreased after DATS treatment. In addition, the mRNA of antioxidant enzymes (superoxide dismutase 2 (SOD2), catalase, glutathione peroxidase 1, 4 (GPx1 and GPx4)) and antioxidant proteins (heme oxygenase-1 (HO-1), superoxide dismutase 1, 2 (SOD1 and SOD2), Γ-glutamylcysteine synthase (Γ-GCSc)) were markedly increased in DOX group compared with the control group, which were significantly attenuated by DATS treatment. The upregulation of antioxidants enzymes in DOX group was probably a compensatory effect against elevated oxidative stress induced by DOX. DATS treatment could ameliorate this oxidative stress in brain. Our results suggested that DATS has potential clinical applications in the prevention of DOX-induced neurotoxicity by ameliorating inflammatory insults and oxidative stress.

Pharmacological modulation of the hydrogen sulfide (H2 S) system by dietary H2 S-donors: A novel promising strategy in the prevention and treatment of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) represents the most common age-related metabolic disorder, and its management is becoming both a health and economic issue worldwide. Moreover, chronic hyperglycemia represents one of the main risk factors for cardiovascular complications. In the last years, the emerging evidence about the role of the endogenous gasotransmitter hydrogen sulfide (H₂ S) in the pathogenesis and progression of T2DM led to increasing interest in the pharmacological modulation of endogenous "H₂ S-system". Indeed, H₂ S directly contributes to the homeostatic maintenance of blood glucose levels; moreover, it improves impaired angiogenesis and endothelial dysfunction under hyperglycemic conditions. Moreover, H₂ S promotes significant antioxidant, anti-inflammatory, and antiapoptotic effects, thus preventing hyperglycemia-induced vascular damage, diabetic nephropathy, and cardiomyopathy. Therefore, H₂ S-releasing molecules represent a promising strategy in both clinical management of T2DM and prevention of macro- and micro-vascular complications associated to hyperglycemia. Recently, growing attention has been focused on dietary organosulfur compounds. Among them, garlic polysulfides and isothiocyanates deriving from Brassicaceae have been recognized as H₂ S-donors of great pharmacological and nutraceutical interest. Therefore, a better understanding of the therapeutic potential of naturally occurring H₂ S-donors may pave the way to a more rational use of these nutraceuticals in the modulation of H₂ S homeostasis in T2DM.