Renoprotective effect of aged garlic extract in streptozotocin-induced diabetic rats

S-1-Propenylcysteine Enhances Endurance Capacity of Mice by Stimulating Fatty Acid Metabolism via Muscle Isoform of Carnitine Acyltransferase-1

BACKGROUND

Endurance is an important capacity to sustain healthy lifestyles. Aged garlic extract (AGE) has been reported to exert an endurance-enhancing effect in clinical and animal studies, although little is known about its active ingredients and mechanism of action.

OBJECTIVES

This study investigated the potential effect of S-1-propenylcysteine (S1PC), a characteristic sulfur amino acid in AGE, on the swimming endurance of mice, and examined its mechanism of action by a metabolomics-based approach.

METHODS

Male Institute of Cancer Research (ICR) mice (6 wk old) were orally administered either water (control) or S1PC (6.5 mg/kg/d) for 2 wk. The swimming duration to exhaustion was measured at 24 h after the final administration. Nontargeted metabolomic analysis was conducted on the plasma samples obtained from mice after 40-min submaximal swimming bouts. Subsequently, the enzyme activity of carnitine acyltransferase-1 (CPT-1) and the content of malonyl-coenzyme A (CoA), acetyl-CoA, and adenosine triphosphate (ATP) were quantified in heart, skeletal muscles, and liver of mice.

RESULTS

The duration time of swimming was substantially increased in the S1PC-treated mice as compared with the control group. Metabolomic analysis revealed significant alterations in the plasma concentration of the metabolites involved in fatty acid metabolism, in particular medium- or long-chain acylcarnitines in the mice treated with S1PC. Moreover, the administration of S1PC significantly enhanced the CPT-1 activity with the concomitant decrease in the malonyl-CoA content in the heart and skeletal muscles. These effects of S1PC were accompanied by the elevation of the acetyl-CoA and ATP levels to enhance the energy production in those tissues.

CONCLUSIONS

S1PC is a key constituent responsible for the endurance-enhancing effect of AGE. This study suggests that S1PC helps provide energy during endurance exercise by increasing fatty acid metabolism via CPT-1 activation in the heart and skeletal muscles.

Evidential support for garlic supplements against diabetic kidney disease: a preclinical meta-analysis and systematic review

Garlic (Allium sativum L.) is a popular spice that is widely used for food and medicinal purposes and has shown potential effects on diabetic kidney disease (DKD). Nevertheless, systematic preclinical studies are still lacking. In this meta-analysis and systematic review, we evaluated the role and potential mechanisms of action of garlic and its derived components in animal models of DKD. We searched eight databases for relevant studies from the establishment of the databases to December 2022 and updated in April 2023 before the completion of this review. A total of 24 trials were included in the meta-analysis. It provided preliminary evidence that supplementing with garlic could improve the indicators of renal function (BUN, Scr, 24 h urine volume, proteinuria, and KI) and metabolic disorders (BG, insulin, and body weight). Meanwhile, the beneficial effects of garlic and its components in DKD could be related to alleviating oxidative stress, suppressing inflammatory reactions, delaying renal fibrosis, and improving glucose metabolism. Furthermore, time-dose interval analysis exhibited relatively greater effectiveness when garlic products were supplied at doses of 500 mg kg-1 with interventions lasting 8-10 weeks, and garlic components were administered at doses of 45-150 mg kg-1 with interventions lasting 4-10 weeks. This meta-analysis and systematic review highlights for the first time the therapeutic potential of garlic supplementation in animal models of DKD and offers a more thorough evaluation of its effects and mechanisms to establish an evidence-based basis for designing future clinical trials.

Optimizing diabetic kidney disease animal models: Insights from a meta-analytic approach

Diabetic kidney disease (DKD) is a prevalent complication of diabetes, often leading to end-stage renal disease. Animal models have been widely used to study the pathogenesis of DKD and evaluate potential therapies. However, current animal models often fail to fully capture the pathological characteristics of renal injury observed in clinical patients with DKD. Additionally, modeling DKD is often a time-consuming, costly, and labor-intensive process. The current review aims to summarize modeling strategies in the establishment of DKD animal models by utilizing meta-analysis related methods and to aid in the optimization of these models for future research. A total of 1215 articles were retrieved with the keywords of "diabetic kidney disease" and "animal experiment" in the past 10 years. Following screening, 84 articles were selected for inclusion in the meta-analysis. Review manager 5.4.1 was employed to analyze the changes in blood glucose, glycosylated hemoglobin, total cholesterol, triglyceride, serum creatinine, blood urea nitrogen, and urinary albumin excretion rate in each model. Renal lesions shown in different models that were not suitable to be included in the meta-analysis were also extensively discussed. The above analysis suggested that combining various stimuli or introducing additional renal injuries to current models would be a promising avenue to overcome existing challenges and limitations. In conclusion, our review article provides an in-depth analysis of the limitations in current DKD animal models and proposes strategies for improving the accuracy and reliability of these models that will inspire future research efforts in the DKD research field.

Bioavailability of Organosulfur Compounds after the Ingestion of Black Garlic by Healthy Humans

The consumption of black garlic has been related to a decreased risk of many human diseases due to the presence of phytochemicals such as organosulfur compounds (OSCs). However, information on the metabolization of these compounds in humans is limited. By means of ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS), this study aims to determine the OSCs and their metabolites excreted in urine 24 h after an acute intake of 20 g of black garlic by healthy humans. Thirty-three OSCs were identified and quantified, methiin (17,954 ± 6040 nmol), isoalliin (15,001 ± 9241 nmol), S-(2-carboxypropyl)-L-cysteine (8804 ± 7220 nmol) and S-propyl-L-cysteine (deoxypropiin) (7035 ± 1392 nmol) being the main ones. Also detected were the metabolites N-acetyl-S-allyl-L-cysteine (NASAC), N-acetyl-S-allyl-L-cysteine sulfoxide (NASACS) and N-acetyl-S-(2-carboxypropyl)-L-cysteine (NACPC), derived from S-allyl-L-cysteine (SAC), alliin and S-(2-carboxypropyl)-L-cysteine, respectively. These compounds are potentially N-acetylated in the liver and kidney. The total excretion of OSCs 24 h after the ingestion of black garlic was 64,312 ± 26,584 nmol. A tentative metabolic pathway has been proposed for OSCs in humans.

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.

A Comprehensive Review on Nutraceuticals: Therapy Support and Formulation Challenges

Nutraceuticals are the nourishing components (hybrid of nutrition and pharmaceuticals) that are biologically active and possess capability for maintaining optimal health and benefits. These products play a significant role in human health care and its endurance, most importantly for the future therapeutic development. Nutraceuticals have received recognition due to their nutritional benefits along with therapeutic effects and safety profile. Nutraceuticals are globally growing in the field of services such as health care promotion, disease reduction, etc. Various drug nutraceutical interactions have also been elaborated with various examples in this review. Several patents on nutraceuticals in agricultural applications and in various diseases have been stated in the last section of review, which confirms the exponential growth of nutraceuticals' market value. Nutraceuticals have been used not only for nutrition but also as a support therapy for the prevention and treatment of various diseases, such as to reduce side effects of cancer chemotherapy and radiotherapy. Diverse novel nanoformulation approaches tend to overcome challenges involved in formulation development of nutraceuticals. Prior information on various interactions with drugs may help in preventing any deleterious effects of nutraceuticals products. Nanotechnology also leads to the generation of micronized dietary products and other nutraceutical supplements with improved health benefits. In this review article, the latest key findings (clinical studies) on nutraceuticals that show the therapeutic action of nutraceutical's bioactive molecules on various diseases have also been discussed.

Insights into the Uses of Traditional Plants for Diabetes Nephropathy: A Review

Diabetic nephropathy (DN) is a serious kidney illness characterized by proteinuria, glomerular enlargement, reduced glomerular filtration, and renal fibrosis. DN is the most common cause of end-stage kidney disease, accounting for nearly one-third of all cases of diabetes worldwide. Hyperglycemia is a major factor in the onset and progression of diabetic nephropathy. Many contemporary medicines are derived from plants since they have therapeutic properties and are relatively free of adverse effects. Glycosides, alkaloids, terpenoids, and flavonoids are among the few chemical compounds found in plants that are utilized to treat diabetic nephropathy. The purpose of this review was to consolidate information on the clinical and pharmacological evidence supporting the use of a variety of medicinal plants to treat diabetic nephropathy.

Antidiabetic and Hypolipidemic Efficiency of Lactobacillus plantarum Fermented Oat (Avena sativa) Extract in Streptozotocin-Induced Diabetes in Rats

Antidiabetic properties of fermented foods have been previously demonstrated. This study aimed to examine the antidiabetic and hypolipidemic potential activities of L. plantarum fermented oat extract in Streptozotocin-induced diabetic rats. Firstly, inoculating 1% of L. plantarum starter culture in 10% whole oat flour in aqueous media resulted in 8.36 log CFU mL−1 and pH 4.60 after 72 h of fermentation at 37 °C. With time progression of oat fermentation, total phenolic content (TPC), antioxidant activity (AOA), and γ-aminobutyric acid (GABA) contents were significantly increased up to 72 h. On the contrary, a significant reduction in β-glucan content was observed only after 72 h of fermentation. Secondly, separated aqueous extracts, i.e., unfermented oat extract (UFOE) and L. plantarum fermented oat extract (LFOE) were examined in vivo in a rat model, which consisted of five groups. Group 1 (negative group, NR); GROUP 2 (positive group, STZ), intraperitoneally injected with a single dose of 45 mg kg−1 BW of Streptozotocin and administered 7 mL of distilled water orally per day; Group 3 (STZ+MET), diabetic rats orally administered 50 mg of metformin kg−1 BW daily; Group 4 (STZ+UFOE), diabetic rats orally administered 7 mL of UFOE daily; and Group 5 (STZ+UFOE), diabetic rats orally administered 7 mL of LFOE daily for 6 weeks. Monitoring random blood glucose (RBG) and fasting blood glucose (FBG) showed that both the UFOE and the LFOE alleviated hyperglycemia in the STZ-induced diabetic rats. The extracts were significantly efficient in improving serum lipid profiles as compared with the positive group. Moreover, liver and kidneys’ functions were improved, and both extracts promoted hepatoprotective and nephroprotective characteristics. Furthermore, the administration of the UFOE and the LFOE efficiently attenuated GSH, CAT, and SOD enzymes and decreased MDA levels as compared with the positive group. In conclusion, data indicate the potential of UFOE and LFOE in future strategies as functional supplements against diabetes and diabetes-related complications.

Pharmacological agents for the prevention of colistin-induced nephrotoxicity

BACKGROUND

Colistin is a polymyxin antibiotic which has been used for treatment of Gram-negative infections, but it was withdrawn due to its nephrotoxicity. However, colistin has gained its popularity in recent years due to the reemergence of multidrug resistant Gram-negative infections and drug-induced toxicity is considered as the main obstacle for using this valuable antibiotic.

RESULTS

In total, 30 articles, including 29 animal studies and one clinical trial were included in this study. These compounds, including aged black garlic extract, albumin fragments, alpha lipoic acid, astaxanthin, baicalein, chrysin, cilastatin, colchicine, curcumin, cytochrome c, dexmedetomidine, gelofusine, grape seed proanthocyanidin extract, hesperidin, luteolin, lycopene, melatonin, methionine, N-acetylcysteine, silymarin, taurine, vitamin C, and vitamin E exhibited beneficial effects in most of the published works.

CONCLUSIONS

In this review, the authors have attempted to review the available literature on the use of several compounds for prevention or attenuation of colistin-induced nephrotoxicity. Most of the studied compounds were potent antioxidants, and it seems that using antioxidants concomitantly can have a protective effect during the colistin exposure.

Use of haematological signatures in conjunction with conventional biomarkers to assess Reno-protective effects of Gedunin in diabetic nephropathy of Streptozotocin induced diabetic rats

Purpose

The present study was aimed at analysing the reno-protective potential of Gedunin (a limonoid from Neem leaves) through haematological and serological assays and renal histopathology studies in streptozotocin induced diabetic rats.

Method

Four weeks old Wister albino rats were chosen for the study. The rats were divided into four groups of 8 rats each. Group 1 (normal control rats); Group 2 (diabetic control rats); Group 3 (Drug control rats: normal rats treated with 1 mg/kg body weight of Gedunin thrice a week through oral gavage for 2 weeks); Group 4 (diabetic rats treated with Gedunin similar to Group 3). Diabetes was induced using a single intraperitoneal injection of streptozotocin (50 mg/kg) in the pre-determined groups. After completion of treatment, the rats were sacrificed and haematological and serological parameters including functional indices of blood cells and renal markers were evaluated through spectrophotometric methods. Renal histology studies were carried out and images were captured on Olympus SC 100, 10 Mega Pixel camera.

Results

Streptozotocin induced diabetes lead to marked reduction in the RBC count, haemoglobin, PCV, WBC count, lymphocyte, elevated levels of fasting blood glucose, kidney function markers such as urea, creatinine, uric acid in rats. Administration of Gedunin significantly (P < 0.05) ameliorated the elevated levels of fasting glucose, RDW%, MCHC%, NLR% and platelet count. A significant reversal of renal tissue damage was also observed.

Conclusion

The restoration of renal serological markers and reversal of renal tissue injuries are all indicative of promising reno-protective potential of Gedunin. Remarkable improvement of haematological parameters supports their use as reno-protection markers.

Black Garlic and Its Bioactive Compounds on Human Health Diseases: A Review

Black garlic (BG) is a form of aged garlic obtained from raw garlic (Allium sativum) via Millard reaction under high temperature (60-90 °C) and humidity (70-90%) for a period of time. Several studies reported higher contents of water-soluble antioxidants compounds (S-allyl cysteine, S-allyl-mercapto cysteine), 5-hydroxymethylfurfural, organosulfur compounds, polyphenol, volatile compounds, and products of other Millard reactions compared to fresh garlic after the thermal processing. Recent studies have demonstrated that BG and its bioactive compounds possess a wide range of biological activities and pharmacological properties that preserve and show better efficacy in preventing different types of diseases. Most of these benefits can be attributed to its anti-oxidation, anti-inflammation, anti-obesity, hepatoprotection, hypolipidemia, anti-cancer, anti-allergy, immunomodulation, nephroprotection, cardiovascular protection, and neuroprotection. Substantial studies have been conducted on BG and its components against different common human diseases in the last few decades. Still, a lot of research is ongoing to find out the therapeutic effects of BG. Thus, in this review, we summarized the pre-clinical and clinical studies of BG and its bioactive compounds on human health along with diverse bioactivity, a related mode of action, and also future challenges.

NADH/NAD+ Redox Imbalance and Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a common and severe complication of diabetes mellitus. If left untreated, DKD can advance to end stage renal disease that requires either dialysis or kidney replacement. While numerous mechanisms underlie the pathogenesis of DKD, oxidative stress driven by NADH/NAD⁺ redox imbalance and mitochondrial dysfunction have been thought to be the major pathophysiological mechanism of DKD. In this review, the pathways that increase NADH generation and those that decrease NAD⁺ levels are overviewed. This is followed by discussion of the consequences of NADH/NAD⁺ redox imbalance including disruption of mitochondrial homeostasis and function. Approaches that can be applied to counteract DKD are then discussed, which include mitochondria-targeted antioxidants and mimetics of superoxide dismutase, caloric restriction, plant/herbal extracts or their isolated compounds. Finally, the review ends by pointing out that future studies are needed to dissect the role of each pathway involved in NADH-NAD⁺ metabolism so that novel strategies to restore NADH/NAD⁺ redox balance in the diabetic kidney could be designed to combat DKD.

Potential application of nanoemulsified garlic oil blend in mitigating the progression of type 2 diabetes-mediated nephropathy in Wistar rats

The renoprotective potential of nanoemulsified garlic oil blend (GNE) in alleviating the progressive stages of hyperlipidemia-mediated diabetic nephropathy was examined. The study was carried out in high fat-fed, streptozotocin-induced type 2 diabetic Wistar rats for five months. The diabetic rats showed a significant increase of area under the curve in OGTT (p < 0.01) and IPITT (p < 0.01), increased urinary albumin (p < 0.01), urinary microprotein (p < 0.001), total cholesterol (p < 0.01), triglycerides (p < 0.001) and LDL cholesterol (p < 0.001), with decreased serum albumin (p < 0.01), serum protein (p < 0.001) and HDL-cholesterol levels (p < 0.05) than the control rats. The histopathological analysis evidenced mesangial expansion and hypercellularity at the end of the first and third month, and glomerulosclerosis and tubular atrophy at the end of the fifth month in diabetic rats. Moreover, on disease progression, increase in urinary podocalyxin, NGAL and CD36 was observed, and the renal mRNA and protein expression of podocalyxin decreased significantly with a concomitant increase in NGAL and CD36 expression from first till fifth month end. The treatment with GNE (20 mg/kg) significantly ameliorated the serum albumin (p < 0.001) and urine albumin (p < 0.01) from the end of the third month with significant attenuation in the lipid profile than GO (20 mg/kg) or Ator (8 mg/kg). Moreover, GNE reverted the histopathological alterations and attenuated the aberrant mRNA, protein expression and urinary excretion level of renal CD36, podocalyxin and NGAL in diabetic rats from an early stage of disease till the end of the study period. This study demonstrated the enhanced efficacy of GO in nanoemulsified form in mitigating the progression of nephropathy in type 2 diabetic rats.

Impact of liraglutide on microcirculation in experimental diabetic cardiomyopathy

Liraglutide is a new therapy used in diabetes and its effect on diabetic complications particularly cardiovascular ones is still under investigated. In our research, we tried to study the effect of liraglutide on experimental diabetic cardiomyopathy (DCM) induced by streptozotocin. We found that liraglutide nearly preserved normal myocardiac structure and significantly protected against myocardiac inflammation and fibrosis that was found in DCM group, p < 0.05. It also increased the density of coronary arteriolar vasculature markedly indicated by significant increase in α SMA (p < 0.05) compared to both DCM and non-diabetic (ND) groups. Moreover, liraglutide decreased TNFα and increased VEGF proteins expression (P < 0.05) compared to DCM group. Conclusion, liraglutide may have a very important role in protecting against experimentally induced diabetic cardiomyopathy by preventing the degenerative changes in the cardiomyocytes and the associated fibrosis, inflammation and decreased vasculature at structural and molecular levels.

Mechanisms of Herbal Nephroprotection in diabetes mellitus

Diabetic nephropathy (DN) is a leading cause of kidney morbidity. Despite the multilayered complexity of the mechanisms involved in the pathogenesis of DN, the conventional treatment is limited to just a few drug classes fraught with the risk of adverse events, including the progression of renal dysfunction. Phytoceuticals offer a promising alternative as they act on the many-sidedness of DN pathophysiology, multitargeting its intricacies. This paper offers a review of the mechanisms underlying the protective action of these phytoagents, including boosting the antioxidant capabilities, suppression of inflammation, averting the proliferative and sclerosing/fibrosing events. The pathogenesis of DN is viewed as a continuum going from the original offense, high glucose, through the noxious products it generates (advanced glycation end-products, products of oxidative and nitrosative stress) and the signaling chains consequently brought into action, to the harmful mediators of inflammation, sclerosis, and proliferation that eventually lead to DN, despite the countervailing attempts of the protective mechanisms. Special attention was given to the various pathways involved, pointing out the ability of the phytoagents to hinder the deleterious ones (especially those leading to, driven by, or associated with TGF-β activation, SREBP, Smad, MAPK, PKC, NF-κB, NLRP3 inflammasome, and caspase), to promote the protective ones (PPAR-α, PPAR-γ, EP4/Gs/AC/cAMP, Nrf2, AMPK, and SIRT1), and to favorably modulate those with potentially dual effect (PI3K/Akt). Many phytomedicines have emerged as potentially useful out of in vitro and in vivo studies, but the scarcity of human trials seriously undermines their usage in the current clinical practice-an issue that stringently needs to be addressed.

Hepatoprotective and Renoprotective Properties of Lovastatin-Loaded Ginger and Garlic Oil Nanoemulsomes: Insights into Serum Biological Parameters

Background and Objectives: Dyslipidemia is gaining much attention among healthcare professionals because of its high association with the malfunctioning of a number of normal physiological and metabolic processes in the body. Obesity is directly interconnected with dyslipidemia and is said to be a denouement of hyperlipidemia and, if left untreated, may lead to intense damage to organs that are directly involved in fat metabolism. The objective of this study was to investigate the synergistic antiobesity and anti-hyperlipidemic activities along with hepato- and renoprotective potential of nanoemulsomes (NES) of lovastatin (LTN)-loaded ginger (GR) and garlic (GL) oils. Materials and Methods: LTN nanoemulsomes co-encapsulated with GR oil and GL oil were prepared by a thin hydration technique. Eight-week-old male Wistar rats weighing 200-250 g were induced with hyperlipidemia via a high-fat diet (HFD) comprising 40% beef tallow. Body weight, serum biochemical lipid parameters, and those for liver and kidney functions, serum TC, LDL-C, vLDL-C, HDL-C, TG, atherogenic index (AI), ALT, AFT, ALP, γ-GT, total protein (TP), serum albumin and globulin ratio (A/G), serum creatinine, blood urea nitrogen (BUN) and blood urea, and histopathology of hematoxylin and eosin (H&E) stained liver and kidney sections of all aforementioned groups were examined in the treated animals. Results: Nanoemulsomes of LTN-loaded GR and GL oils provided synergistic effects with LTN, exerted better ameliorative actions in reducing serum TC, LDL-C, vLDL-C, triglycerides, and AI, and improved serum HDL-C levels. Serum ALT, AST, ALP, and γ-GT levels were in the normal range for nanoemulsome groups. H&E stained liver and kidney sections of these animals confirmed better hepatoprotective and renoprotective effects than LTN alone. Serum biochemical parameters for renal functions also claimed to be in the moderate range for nanoemulsome-treated groups. Conclusion: This study demonstrated that nanoemulsomes of LTN-loaded GR and GL oils synergistically provided better antihyperlipidemic, hepatoprotective, and renoprotective effects as compared to LTN alone.

Enhanced Therapeutic Potency of Nanoemulsified Garlic Oil Blend Towards Renal Abnormalities in Pre-diabetic Rats

The therapeutic potency of ultrasonic nanoemulsified garlic oil blend using a non-ionic surfactant (Tween 80) was assessed on pre-diabetic Wistar rats with microalbuminuria. The pre-diabetic condition was induced in male albino Wistar rats by supplementing high-fat diet. The prolonged period of the pre-diabetic state caused renal dysfunctioning, which was indicated by microalbuminuria. Treatment of pre-diabetic rats with nanoemulsified garlic oil blend significantly ameliorated the lipid profile (p < 0.001), urinary albumin (p < 0.01), microprotein (p < 0.001), urinary triglycerides (p < 0.01), serum triglycerides (p < 0.01), serum albumin (p < 0.05), and protein levels (p < 0.01) in comparison to treatment of pre-diabetic rats with garlic oil blend or atorvastatin. Similarly, histopathological investigations indicated a remarkable attenuation in the mesangial expansion and proliferation, glomerular and tubular basement membrane thickening, and the tubular lipid deposits on administering nanoemulsified garlic oil blend than garlic oil blend or atorvastatin. Moreover, nanoemulsified garlic oil blend significantly promoted renal podocin gene expression by 3.98-fold (p < 0.001) and attenuated increased urinary podocin level by 2.92-fold (p < 0.01). Thus, our study affirms that the efficacy of garlic oil blend was augmented upon nanoemulsification, which substantially ameliorated the renal abnormalities observed in the pre-diabetic condition than garlic oil blend or atorvastatin.

Mangosteen Vinegar Rind from Garcinia mangostana Prevents High-Fat Diet and Streptozotocin-Induced Type II Diabetes Nephropathy and Apoptosis

Type II diabetes (T2D) nephropathy, a major cause of end-stage kidney disease, progresses and develops from oxidative stress. Natural polyphenols can protect the kidney from diabetic nephropathy exerting antioxidant activities. The present approach enumerates the reno-protective and anti-apoptotic effects of mangosteen vinegar rind (MVR, a phenolic aqueous extract) against high-fat diet (5 g/day up to five weeks)-/streptozotocin (single ip, dose 30 mg/kgBW)-induced T2D nephropathy of albino mice. In vitro total phenolic content, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) activity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant capacity, and α-amylase inhibition activity as antidiabetic assay of MVR were performed. In vivo mice body weight, oral glucose, and maltose tolerance test, metabolic parameters (plasma glucose, insulin level, omeostasis model assessment-estimated insulin resistance), biochemical parameters (kidney hypertrophy, blood urea nitrogen, creatinine), oxidative stress parameters (malondialdehyde, superoxide dismutase, catalase) were estimated in an intervention study. Additionally, renal morphology and early apoptosis were observed following the H & E staining and TUNEL assay of the tissue frozen section. We found that the aqueous extract of MVR possesses potent in vitro antioxidative and antidiabetic activities. Animal intervention results showed that MVR 100, 200 mg/kgBW, and Glibenclamide 60 mg/kgBW treatments significantly improved (P < 0.05) the abovementioned parameters compared to the diabetic control group. Furthermore, treatments also significantly restored (P < 0.05) kidney histological alterations and reduced cellular apoptosis compared to the diabetic control group. These findings concluded that MVR treatments significantly modulated the glucose intolerance, metabolic alterations, and oxidative stress-induced pathological alterations and cellular apoptosis of diabetic kidney. PRACTICAL APPLICATION: Garcinia mangostana, a polyphenol rich natural product, is obtained from the tropical rain forest area of Southeast Asian countries and processes diverse biological activities including antioxidant, anti-proliferative, anti-inflammatory, anti-carcinogenic, and so on. This research first time focuses on the nephro-protective and anti-apoptotic effects of mangosteen vinegar rind (MVR) from the mangosteen fruit pericarp. Our study provides the efficient data to prove the beneficial effect of MVR as a dietary supplement for the prevention and management of diabetic nephropathy.

A mini review: garlic extract and vascular diseases

Vascular diseases refer to medical conditions that narrow blood vessels. Narrowed cardiac or cerebral arteries can lead to myocardial infarction or ischemic stroke. Risk factors including atherosclerosis, hypertension, and diabetes may induce either cardiovascular or cerebral complications. Based on current research, garlic favorably affects atherosclerosis, hypertension and diabetes, and helps decrease the risk of myocardial infarction and ischemic stroke. Garlic has been utilized for hundreds of years as a natural health remedy. New research is emerging regarding its effectiveness in treating common diseases, including atherosclerosis, hypertension, and diabetes. The underlying mechanisms by which garlic, and its byproducts, can alter pathophysiology have begun to be elucidated by these studies. Garlic is a prominent topic for future research regarding its potential as an adjuvant to conventional pharmacotherapy for these common health conditions. In this mini-review, we discuss the current state of the literature regarding garlic and its effects in patients with vascular disease. Specifically, we decided to briefly discuss the key points regarding the mechanisms underlying garlic's anti-hypertensive, anti-hyperlipidemic, and hypoglycemic effects. This allows the readers to understand each process while keeping the paper concise. These mechanisms can be further explored in the original articles, at the reader's discretion.

Antioxidative Effects of Natural Products on Diabetic Cardiomyopathy

Diabetic cardiomyopathy (DCM) is a common and severe complication of diabetes and results in high mortality. It is therefore imperative to develop novel therapeutics for the prevention or inhibition of the progression of DCM. Oxidative stress is a key mechanism by which diabetes induces DCM. Hence, targeting of oxidative stress-related processes in DCM could be a promising therapeutic strategy. To date, a number of studies have shown beneficial effects of several natural products on the attenuation of DCM via an antioxidative mechanism of action. The aim of the present review is to provide a comprehensive and concise overview of the previously reported antioxidant natural products in the inhibition of DCM progression. Clinical trials of the antioxidative natural products in the management of DCM are included. In addition, discussion and perspectives are further provided in the present review.

The novel mitochondria-targeted hydrogen sulfide (H2S) donors AP123 and AP39 protect against hyperglycemic injury in microvascular endothelial cells in vitro

The development of diabetic vascular complications is initiated, at least in part, by mitochondrial reactive oxygen species (ROS) production in endothelial cells. Hyperglycemia induces superoxide production in the mitochondria and initiates changes in the mitochondrial membrane potential that leads to mitochondrial dysfunction. Hydrogen sulfide (H₂S) supplementation has been shown to reduce the mitochondrial oxidant production and shows efficacy against diabetic vascular damage in vivo. However, the half-life of H₂S is very short and it is not specific for the mitochondria. We have therefore evaluated two novel mitochondria-targeted anethole dithiolethione and hydroxythiobenzamide H₂S donors (AP39 and AP123 respectively) at preventing hyperglycemia-induced oxidative stress and metabolic changes in microvascular endothelial cells in vitro. Hyperglycemia (HG) induced significant increase in the activity of the citric acid cycle and led to elevated mitochondrial membrane potential. Mitochondrial oxidant production was increased and the mitochondrial electron transport decreased in hyperglycemic cells. AP39 and AP123 (30–300 nM) decreased HG-induced hyperpolarisation of the mitochondrial membrane and inhibited the mitochondrial oxidant production. Both H₂S donors (30–300 nM) increased the electron transport at respiratory complex III and improved the cellular metabolism. Targeting H₂S to mitochondria retained the cytoprotective effect of H₂S against glucose-induced damage in endothelial cells suggesting that the molecular target of H₂S action is within the mitochondria. Mitochondrial targeting of H₂S also induced >1000-fold increase in the potency of H₂S against hyperglycemia-induced injury. The high potency and long-lasting effect elicited by these H₂S donors strongly suggests that these compounds could be useful against diabetic vascular complications.

Renoprotective effect of a combination of garlic and telmisartan against ischemia/reperfusion-induced kidney injury in obese rats

Obesity enhances the frequency and severity of acute kidney injury (AKI). Telmisartan pre-treatment was used experimentally in the amelioration of ischemia/reperfusion (IR)-induced AKI. However, there is a lack of evidence regarding its beneficial effects on AKI in obese animals. The present study, therefore, aimed to explore the protective effects of garlic and/or telmisartan against renal damage induced by unilateral IR in obese rats. Meloxicam was used as a standard anti-inflammatory agent. Prophylactic oral administration of meloxicam (3 mg kg(-1)), garlic (500 mg kg(-1)) and/or telmisartan (5 and 10 mg kg(-1)) for 4 wk protected against renal function deterioration induced by IR in obese rats. Both doses of telmisartan significantly reduced serum total cholesterol and triacyglycerol levels as well as peri-renal adipocytes size and renal fibrosis. Renal nuclear factor-kappa B immunoreactivity, tumor necrosis factor-alpha content as well as interleukin-10, adiponectin receptor 1 and macrophages (M1, M2) polarization markers (CD11c, CD206) mRNA expressions were down-regulated in ischemic kidney tissues and white adipose tissues around them by all treatments. Moreover, garlic, telmisartan and their combinations significantly suppressed oxidative stress in renal ischemic tissues. Histological picture was also improved by these treatments. Interestingly, the combinations provided a greater protection than their monotherapy in a dose-dependent manner. We suppose that this combination may be a promising prophylactic regimen for managing AKI in case of obesity. Thus, future experimental and clinical large-scale studies are necessary.

Anti-diabetic and anti-oxidant potential of aged garlic extract (AGE) in streptozotocin-induced diabetic rats

Background

Although aged garlic extract (AGE) shares some active components with fresh garlic and in spite of its palatability and milder side effects, the anti-diabetic and related anti-oxidant properties of AGE have not been investigated extensively, and the reported findings are inconsistent.

This study investigated the anti-diabetic effects of 3 incremental doses of AGE in streptozotocin (STZ)-induced diabetic rats (fasting blood sugar > 20 mM).

Method

Diabetic rats were divided into a control diabetic group (CD) and AGE-treated diabetic group (AGE-D). The AGE-D was divided into 3 groups and accordingly treated with AGE i.p. at 100, 300 and 600 mg/kg daily for 8 weeks. A control normal group (CN) was also included for reference.

Results

Compared to the CN group, the CD group showed significant loss of body weight (over 50 %); and decreased serum insulin concentration (10 fold) and total anti-oxidant level and catalase activity (45–70 %) in serum, kidney and liver. Conversely, the CD rats had an elevated blood glucose (nearly 4 fold), serum cholesterol (nearly 2 fold) and triglycerides (>2 fold), erythrocyte glycated hemoglobin (GHb, 3 fold) and kidney and liver lipid peroxidation (MDA levels). Treatment with AGE positively reversed the diabetic changes in the targeted parameters to levels significantly lower than those measured in the CD group and the degrees of attenuation were almost dose dependent especially with the two higher doses.

Conclusion

AGE exhibits a dose-dependent ameliorative action on indicators of diabetes in STZ-induced diabetic rats.

Renoprotective effect of lansoprazole in streptozotocin-induced diabetic nephropathy in wistar rats

Proton pump inhibitors (PPIs) have exhibited glucose lowering action in animal models of diabetes; however, their potential in diabetes-related complications has not yet been evaluated. Hence, the present study has been undertaken to investigate the renoprotective potential of lansoprazole in streptozotocin-induced diabetic nephropathy in wistar rats. Diabetic nephropathy was induced with a single injection of streptozotocin (STZ, 45 mg/kg, i.p.). Lansoprazole (40 mg/kg; 80 mg/kg, p.o.; 4 weeks) was administered to diabetic rats after 4 weeks of STZ treatment. A battery of biochemical tests such as serum glucose, glycated hemoglobin, blood urea nitrogen (BUN), serum creatinine, albumin, and kidney weight/body weight (%) ratio were performed to evaluate the renal functions. Oxidative stress was determined by estimating renal thiobarbituric acid reactive species (TBARS) and reduced glutathione (GSH) levels. Lipid profile was assessed by determining serum cholesterol (TC), triglyceride (TG), and high-density lipoprotein (HDL). The STZ-treated rats demonstrated deleterious alterations in kidney functions, enhanced oxidative stress, and disturbed lipid profile. Administration of lansoprazole to diabetic rats significantly reduced serum glucose, glycated hemoglobin, BUN, creatinine, albumin levels, and oxidative stress. Serum lipids like TC and TG were decreased, and HDL was enhanced in lansoprazole-treated STZ rats. The findings of our study indicate that renoprotective effects of lansoprazole may be attributed to its glucose-lowering, lipid-lowering, and antioxidative potential.

The inhibitory effects of γ-glutamylcysteine derivatives from fresh garlic on glycation radical formation

The effects of three reactive peptides, γ-glutamylmethylcysteine (γ-GMC), γ-glutamylpropylcysteine (γ-GPC), and γ-glutamylbutylcysteine (γ-GBC) on the suppression of reactive radicals during the heating of l-lysine in the presence or absence of glucose was studied by electron spin resonance spectroscopy. γ-GMC and γ-GPC were extracted from fresh garlic, and γ-GBC was a synthetic peptide. The results showed that γ-GMC and γ-GPC effectively suppress formation of l-lysine radicals, but that γ-GBC exhibits low radical inhibition. The origin of the short peptides, and the length of their side chain, influenced their surface hydrophobicity and subsequent radical inhibition. In addition, the oxidation of l-lysine was inhibited by the peptides in a similar manner to their inhibition of the Maillard reaction (MR), and their radical inhibition was consistent with similar activity towards N(ε)-(carboxymethyl)lysine (CML).

Histopathological study of the combination of metformin and garlic juice for the attenuation of gentamicin renal toxicity in rats

INTRODUCTION

Tubular toxicity is one of the most important side effects of aminoglycoside antibiotics, especially gentamicin.

OBJECTIVES

We histopathologically studied the effect of garlic extract and metformin co-administration, in attenuation of genetamicin induced tubular toxicity in rats.

MATERIALS AND METHODS

In this study seventy rats were divided into seven equal groups and except group 1 (control) were injected 100 mg/kg/day gentamicin (GM) intraperitoneally (i.p.) for 10 days. Other than GM, group III received 20 mg/kg garlic (i.p.), group IV metformin (MF) (100 mg/kg, orally), group V a combination of MF with garlic juice (100 and 20 mg/kg/day, respectively) and group VI a combination of MF and garlic juice (50 and 10 mg/kg/day, respectively) for following 10 days. Group VII received a combination of MF and garlic juice (100 and 20 mg/kg, respectively) along with GM. Animals were sacrificed on the 20(th) day of the experiment and the kidneys were removed for histological examinations.

RESULTS

GM induced nephrotoxicity and garlic or MF alone and a combination of both with high doses (not low doses) significantly abolished the kidney tubular injury induced by GM. In addition, co-administration of GM, MF and garlic (group 7) prevented the GM- induced tissue damage more than the groups in which MF and garlic were injected 10 days post GM administration.

CONCLUSION

Garlic extract and Metformin, alone or in a combination, might be safely used to ameliorate GM induced tubular toxicity.