Combination effect of voluntary exercise and garlic (Allium sativum) on oxidative stress, cholesterol level and histopathology of heart tissue in type 1 diabetic rats

A scoping review on natural cholesterol lowering supplements sold in South African pharmacies

Background

Dyslipidaemia is defined as elevated total or low-density lipoprotein (LDL) levels or low levels of high-density lipoprotein (HDL). Patients may often make use of natural cholesterol lowering supplements (NCLSs) available at the pharmacy; however, limited information on these supplements is readily available. Pharmacists should be knowledgeable about NCLSs to ensure that the use of these supplements is supported by evidence and to provide appropriate advice to patients for desirable therapeutic outcomes.

Aim

This study aimed to identify the NCLSs being sold in South African pharmacies and review the scientific evidence for each of the ingredients in these NCLSs.

Methods

Seventeen NCLS products were identified, and the Joanna Briggs Institute (JBI) scoping review methodology was used to conduct a literature review of NCLSs.

Results

From the ingredients reviewed it is evident that co-enzyme Q10, probiotics and sterols have sufficient evidence supporting their use. However, there is still limited scientific evidence available to validate the remaining ingredients.

Conclusion

Further research on NCLSs will provide practising pharmacists and practitioners with a guide of the evidence available on the various ingredients in NCLSs.

Contribution

This study provides a review of the available literature on the NCLSs being sold in the pharmacies across South Africa to provide pharmacists with a collated document of the evidence behind these popular supplements to assist them in making evidence based informed decision regarding natural products for cholesterol.

Effect of SGLT2 Inhibitor on Cardiomyopathy in a Rat Model of T2DM: Possible involvement of Cardiac Aquaporins

Diabetic cardiomyopathy (DCM) causes arrhythmia, heart failure, and sudden death. Empagliflozin, an SGLT-2 (Sodium glucose co-transporter) inhibitor, is an anti-diabetic medication that decreases blood glucose levels by stimulating urinary glucose excretion. Several aquaporins (AQPs) including AQP-1-3 and - 4 and their involvement in the pathogenesis in different cardiac diseases were detected. In the current study the effect of Empagliflozin on diabetic cardiomyopathy and the possible involvement of cardiac AQPs were investigated.

METHODS

56 adult male Sprague-Dawley rats were divided into 4 groups: Control, DCM: type 2 diabetic rats, low EMPA+DCM received empagliflozin (10 mg/kg/day) and high EMPA+DCM received empagliflozin (30 mg/kg/day) for 6 weeks.

RESULTS

Administration of both EMPA doses, especially in high dose group, led to significant improvement in ECG parameters. Also, a significant improvement in biochemical and cardiac oxidative stress markers (significant decrease in serum CK-MB, and malondialdehyde while increasing catalase) with decreased fibrosis and edema in histopathological examination and a significant attenuation in apoptosis (caspase-3) and edema (AQP-1& -4).

CONCLUSION

Both doses of Empagliflozin have a cardioprotective effect and reduced myocardial tissue edema with high dose having a greater effect. This might be due to attenuation of oxidative stress, fibrosis and edema mediated through AQP-1, - 3& - 4 expression.

Basic Chemical Composition, Antioxidant Activity and Selected Polyphenolic Compounds Profile in Garlic Leaves and Bulbs Collected at Various Stages of Development

Garlic is commonly used as vegetable or spice and as a herb in folklore as well as traditional medicine in many countries. The current study aimed to compare the chemical composition, antioxidant activity, and the content of selected polyphenolic compounds in cloves as well as leaves of winter garlic plants of the Harnaś and Ornak cultivars, which are of Polish origin. Garlic was grown from cloves for three years (2018-2020) in the experimental field of the University of Agriculture in Krakow, Poland. The research material was harvested on three dates: May; June, unripe garlic plants; and in July, the plant at full maturity. The content of vitamin C in the fresh material was determined. The proximate analysis was determined in the freeze-dried plants of garlic, and the total carbohydrate content was calculated. The antioxidant activity and the content of selected polyphenolic compounds were also determined. Garlic cloves showed a higher content of dry matter, and total carbohydrates than the leaves of garlic plants. On the other hand, in the leaves, a significantly higher content of protein, total fat and ash were observed. Additionally, garlic leaves were characterised by a higher content of vitamin C, total polyphenols, and a higher antioxidant activity than garlic cloves. The leaves of young garlic plants from the May harvest were distinguished by a higher content of these compounds. The dominant phenolic compounds were catechin and epicatechin. The leaves of young plants can be a valuable source of bioactive substances, especially in early spring.

The effects of resveratrol and melatonin on biochemical and molecular parameters in diabetic old female rat hearts

The roles of melatonin and resveratrol-enhanced activation of SIRT1 (silent information regulator 1), GLUT4 (glucose transporter type 4), and PGC-1α (peroxisome proliferator-activated receptor gamma coactivator 1-alpha) in mediating the protective effects on the heart in aged female rats with streptozotocin-induced diabetes were investigated. 16-month-old 48 Wistar female rats were separated into 8 groups with equal numbers. Group 1: Control, Group 2: Resveratrol Control, Group 3: Melatonin Control, Group 4: Resveratrol and Melatonin Control, Group 5: Diabetes, Group 6: Diabetes Resveratrol, Group 7: Diabetes Melatonin, Group 8: Diabetes Resveratrol and Melatonin. A single dose of 40 mg/kg intraperitoneal streptozotocin was injected into the rats of Groups 5, 6, 7, and 8 to induce experimental diabetes. Blood glucose levels were measured from the tail veins of the animals six days after the injections, using a diagnostic glucose kit. Rats with a blood glucose levels ≥300 mg/dl were considered diabetic. 5 mg/kg/day of resveratrol (intraperitoneal) and melatonin (subcutaneous) were administered for four weeks. At the end of the applications, SIRT1, GLUT4, PGC-1α gene expression as well as MDA and GSH levels in the heart tissues were determined by the PCR method from heart tissue samples taken under general anesthesia. The findings of our study show that suppressed antioxidant activity and decreased GLUT4, SIRT1, and PGC-1α gene expression in heart tissue can be reversed by the combination of resveratrol, melatonin, and resveratrol + melatonin in a diabetic aged female rat model. Resveratrol and melatonin supplementation may have a protective effect on cardiac functions in the diabetic aged female rat model.

Moderate-Intensity Exercise Maintains Redox Homeostasis for Cardiovascular Health

It is well known that exercise is beneficial for cardiovascular health. Oxidative stress is the common pathological basis of many cardiovascular diseases. The overproduction of free radicals, both reactive oxygen species and reactive nitrogen species, can lead to redox imbalance and exacerbate oxidative damage to the cardiovascular system. Maintaining redox homeostasis and enhancing anti-oxidative capacity are critical mechanisms by which exercise protects against cardiovascular diseases. Moderate-intensity exercise is an effective means to maintain cardiovascular redox homeostasis. Moderate-intensity exercise reduces the risk of cardiovascular disease by improving mitochondrial function and anti-oxidative capacity. It also attenuates adverse cardiac remodeling and enhances cardiac function. This paper reviews the primary mechanisms of moderate-intensity exercise-mediated redox homeostasis in the cardiovascular system. Exploring the role of exercise-mediated redox homeostasis in the cardiovascular system is of great significance to the prevention and treatment of cardiovascular diseases.

Acute and subchronic 90-days toxicity assessment of propyl-propane-thiosulfinate (PTS) in rats

The organosulfur compounds (OSC) extracted from Allium spp. exhibit antibacterial, antifungal, and antioxidant properties. The agri-food industry is taking advantage of these properties by using them as natural feed and food additives. In the present work, an acute and a subchronic 90-days toxicity studies have been conducted for the first time to assess the safety of the OSC propyl-propane-thiosulfinate (PTS). Both studies were carried out following the Organization for Economic Co-operation and Development test guidelines (425 and 408, respectively). The acute study provided a maximum tolerated dose (MTD) of 175 mg/kg and the subchronic study established the Non Observed Adverse Effect Level (NOAEL) ≥ 55 mg/kg body weight (b.w.)/day in both sexes. In addition, the subchronic study performed on rats exposed to 14, 28 and 55 mg/kg b.w./day PTS, revealed no changes in any of the hematological parameters measured as well as no differences in body weight and water/food consumption. However, biochemical parameters were altered in some groups, although they were not biologically significant (Ca2+ in female rats, and the thyroids hormones T3 and T4 in rat males). Furthermore, the histopathological assessment evidenced no abnormality on the gastrointestinal, respiratory, lymphoid, urinary, circulatory, nervous, musculoskeletal, and reproductive systems.

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.

Voluntary exercise improves sperm parameters in high fat diet receiving rats through alteration in testicular oxidative stress, mir-34a/SIRT1/p53 and apoptosis

OBJECTIVES

High fat diet can lead to testicular structural and functional disturbances, spermatogenesis disorders as well as infertility. So, the present investigation was proposed to clarify whether voluntary exercise could prevent high fat diet induced reproductive complications in rats through testicular stress oxidative and apoptosis.

METHODS

Forty male Wistar rats were randomly divided into four groups; control (C), voluntary exercise (VE), high fat diet (HFD) and high fat diet and voluntary exercise (VE + HFD) groups. The rats in the VE and VE + HFD groups were accommodated in apart cages that had running wheels and the running distance was assessed daily for 10 weeks. In VE + HFD group, animals were fed with HFD for five weeks before commencing exercise. The sperm parameters, the expressions of testicular miR-34a gene, and P53 and SIRT1 proteins as well as testicular apoptosis were analyzed in all groups.

RESULTS

The results indicated that voluntary exercise in VE + HFD group led to significantly increased GPX and SOD activities, SIRT1 protein expression, sperm parameters, and decreased the expression of miR34a gene and Acp53 protein, and cellular apoptosis index compared to HFD group (p<0.001 to p<0.05). The SOD and catalase activities, SIRT1 protein expression, sperm parameters in VE + HFD group were lower than of those of VE group, however, MDA content, expression of Acp53 protein, apoptosis indexes in VE + HFD group was higher than that of VE group (p<0.001 to p<0.05).

CONCLUSION

This study revealed that voluntary exercise improved spermatogenesis, in part by decreasing the testicular oxidative stress status, apoptosis through alteration in miR-34a/SIRT1/p53 pathway.

Pathophysiology, Clinical Characteristics of Diabetic Cardiomyopathy: Therapeutic Potential of Natural Polyphenols

Diabetic cardiomyopathy (DCM) is an outcome of disturbances in metabolic activities through oxidative stress, local inflammation, and fibrosis, as well as a prime cause of fatality worldwide. Cardiovascular disorders in diabetic individuals have become a challenge in diagnosis and formulation of treatment prototype. It is necessary to have a better understanding of cellular pathophysiology that reveal the therapeutic targets and prevent the progression of cardiovascular diseases due to hyperglycemia. Critical changes in levels of collagen and integrin have been observed in the extracellular matrix of heart, which was responsible for cardiac remodeling in diabetic patients. This review explored the understanding of the mechanisms of how the phytochemicals provide cardioprotection under diabetes along with the caveats and provide future perspectives on these agents as prototypes for the development of drugs for managing DCM. Thus, here we summarized the effect of various plant extracts and natural polyphenols tested in preclinical and cell culture models of diabetic cardiomyopathy. Further, the potential use of selected polyphenols that improved the therapeutic efficacy against diabetic cardiomyopathy is also illustrated.

The impacts of garlic and voluntary training alone or together on myocardial miR-126 and miR-210 gene expressions and angiogenesis in healthy rats

Introduction: microRNAs (miRs) play a critical role in both physiological and pathological processes. Recent studies have shown that garlic and exercise training have many beneficial effects in different disorders including cardiovascular disease. However, their mechanisms have not been fully understood. This study sought to investigate the impact of garlic and voluntary training alone or together on themiR-126 and miR-210 gene expressions and cardiac angiogenesis. Methods: Male Wistar rats were divided into four groups (n=7): (1) Control, (2) Garlic, (3) Exercise, and (4) Garlic+ Exercise. Animals were gavaged with raw fresh garlic homogenate (250 mg/kg body weight/day) or were subjected to voluntary training alone or together for about 6 weeks. The expressions of miR-126 and miR-210 in the heart tissue were measured by real-time PCR and lipid profile in serum was assessed by enzymatic kits. Angiogenesis was determined by immuno staining detection of PECAM-1 and CD31 in the heart tissue. Results: Garlic and exercise up-regulated myocardial miR-126 (P < 0.01), miR-210 (P < 0.001)expressions, and angiogenesis (P < 0.001) which was evidenced by higher CD31 expression. Besides, combination of garlic and exercise amplified their effects on those parameters (P < 0.001). Moreover, both voluntary exercise and garlic alone (P < 0.01) or together (P < 0.001) markedly modulated serum lipid profile. Conclusion: Voluntary exercise and garlic treatment for 6 weeks enhanced myocardial angiogenesis. These alterations were partly due to the increment of miR-126 and miR-210 expressions in the heart tissue in relation to improvement in lipid profile.

Attenuated Renal and Hepatic Cells Apoptosis Following Swimming Exercise Supplemented with Garlic Extract in Old Rats

Background/Objective

One of the problems associated with aging is the development of apoptosis in different tissues. There is evidence that physical activity and herbal remedies can be useful. This study aimed to determine the effect of swimming training (SW) alone or combined with garlic extract on renal and hepatic cells apoptosis, as wellas on the liver and kidney function biomarkers in old rats.

Methods

A total of 35 old rats (aged 40–50 weeks) were randomly divided into 5 groups including control, saline (S), exercise training (ET), garlic (G) and exercise training+ garlic (ET.G) groups. Exercise was started for 5 min/day and then gradually extended to 60 min/day and the G and E+G groups received 1 mL/kg of this mixture by gavage. Twenty-four hours after completion of 8 weeks training, liver, kidney and blood samples were collected for histopathological examinations, liver and kidney functions, oxidative stress and apoptosis biomarkers.

Results

The tissue sections of the SW exercise, control and saline groups showed some mild histopathological changes in liver and kidney, while SW supplemented with garlic prevented these damages. The SW alone or supplemented with garlic significantly increased the Bcl-2 value and declined the BAX level in both liver and kidney (p<0.05). The activities of catalase (CAT) and superoxide dismutase (SOD) in the liver and kidney of the control and saline groups were lower than those in E, G and G+E groups, while a significant increase for malondialdehyde (MDA) value was found in the control and saline groups. Furthermore, the E+G significantly declined the activity of hepatic (ALT, AST and ALP) and renal damage (uric acid, urea and creatinine) biomarkers compared to the control and saline groups (p<0.05).

Discussion

Swimming exercise supplemented with garlic extract not only improves antioxidant capacity but also declines oxidative damages and apoptosis through reducing Bax levels and enhancing Bcl-2 value.

Modulatory effect of tropisetron in the liver of streptozotocin-induced diabetes in rats: biochemical and histological evidence

Objectives There is an association between diabetes and liver disorders. Oxidative stress plays a crucial role in the pathology of hepatic abnormalities in diabetes. In this study, the effect of Tropisetron on the oxidative damage and histological alterations in the liver of type 1 diabetes mellitus (DM) were evaluated. Methods Thiry-five male Wistar rats were randomly divided into five experimental groups (n = 7): control (C), tropisetron (T), diabetes (D), diabetes + tropisetron (D + T) and diabetes + glibenclamide (D + G). A single injection of streptozotocin (STZ, 50 mg/kg; i.p) was used to induce diabetes. Tropisetron (3 mg/kg; i.p), as a 5-HT3 receptor antagonist and glibenclamide (1 mg/kg; i.p), as a positive control were given once daily for 2 weeks. Finally, animals were euthanized and liver samples were obtained for histopathological examination and biochemical measurements including malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx) levels. Results There is a significant increase in MDA (p < 0.001) level and a significant decrease (p < 0.001) in SOD and GPx contents in diabetic animals. Tropisetron attenuated MDA levels (p < 0.001) and enhanced SOD (p < 0.05) and GPx (p < 0.01) activities accompanied by histopathological improvement in the diabetes liver. Similar results were achieved in the rats treated with the standard drug, namely: glibenclamide. Conclusions Our findings indicate that tropisetron mitigates liver damage in the diabetes rats in part by attenuation of oxidative stress.

Alliin, an Allium sativum Nutraceutical, ReducesMetaflammation Markers in DIO Mice

Obesity generates a chronic low-grade inflammatory state which promotes oxidative stress and triggers comorbidities. Alliin is the main organosulfur compound in garlic and has been shown to induce a decrease in the expression of proinflammatory cytokines; its systemic effect on metabolic parameters and adipose tissue is not yet known, however. After nine weeks of HFD and with obesity established in C57BL/6 mice, we observed that a daily treatment with alliin for 3.5 weeks (15 mg/kg) did not affect body weight, but significantly improved insulin sensitivity and glucose tolerance, both evaluated through a blood glucose monitoring system. Once alliin treatment was completed, serum, adipose tissue, and organs of interest related to metabolism were removed for further analysis. We observed that alliin significantly decreased the size of adipocytes from epididymal adipose tissue, evaluated via microscopy. A decrease in gene expression and serum protein levels of the adipocytokines leptin and resistin, as well as decreased serum IL-6 concentration, were detected by qRT-PCR and ELISA, respectively. It did not, however, affect mRNA expression of antioxidant enzymes in the liver. Taken altogether, these results indicate that treatment with alliin reduces metaflammation markers in DIO mice and improves some metabolic parameters without affecting others.

Involvement of endocannabinoid system, inflammation and apoptosis in diabetes induced liver injury: Role of 5-HT3 receptor antagonist

Confident relationships between diabetes andliver damagehave previously been established. This study was designed to evaluate hepaticinflammation, apoptosis, and endocannabinoid system alterations in diabetes with or withouttropisetrontreatment. Rats were assigned to five equal groups: control, tropisetron, diabetes, tropisetron+diabetes, and glibenclamide+diabetes (n = 7 in each group). Rats were treated with tropisetron (3 mg/kg) and glibenclamide (1 mg/kg) as a positive control for two weeks after type 1 diabetes induction.Inflammatory cytokines tumor necrosis factor-alpha and interleukin 6 (TNF-α and IL-6) levels, apoptotic cells, and fatty acid amide hydrolase (FAAH) enzyme, at both transcriptional and protein levels increased, while the gene expression of cannabinoid receptor 1 (CB1) and its protein level decreased in the diabetic liver compared to the control. Treatment with tropisetron reversed TNF-α, apoptotic index, and endocannabinoid system components. These effects were equipotent with glibenclamide, indicating that tropisetroncan protect liver tissue against diabetic disturbances. These findings strongly support the idea that diabetes-induced liver abnormality is mediated by inflammatory reactions, apoptosis, and endocannabinoid system, and that these effects can be alleviated by using tropisetron as an antioxidant and anti-inflammatory agent.

Prevention of arachidonic acid-induced liver injury by controlling oxidative stress-mediated transglutaminase activation with garlic extracts

Garlic and its sulfur constituents have numerous biological functions, such as antioxidant, anti-inflammatory, anti-microbial, anticancer, antidiabetic and cardioprotective effects. Fatty liver diseases, such as non-alcoholic steatohepatitis, which is characterized by the accumulation of lipids and oxidative stress in hepatocytes and continual liver damage, has attracted much attention, and it is believed that it will become the leading etiology of liver cancer. We have previously reported that the growth-suppressive effects of arachidonic acid (AA), an unsaturated fatty acid known to be a pro-inflammatory precursor, is accompanied by the production of reactive oxygen species followed by the nuclear accumulation and activation of the protein crosslinking enzyme, transglutaminase (TG)2. In this study, we examined the potential role of garlic extracts in preventing the growth-suppressive effects of AA on human hepatic cells. We also aimed to provide a mechanistic insight regarding the association between the hepatoprotective effects of garlic extract and the inhibition of the TG-related crosslinking of nuclear proteins, which is not associated with hepatic lipid partitioning mediated by stearoyl-CoA desaturase-1. Given the critical roles of unsaturated fatty acids in the regulation of cancer cell stemness and immune surveillance in the context of chronic injury, we propose that garlic extracts may serve as a therapeutic option for the prevention of chronic liver injury and inflammation, as well as for the prevention of the carcinogenesis of fatty livers.