Alterations in Plasma Glucose and Cardiac Antioxidant Enzymes Activity in Streptozotocin-Induced Diabetic Rats: Effects of Trigonella foenum-graecum Extract and Swimming Training

Fabrication and characterization of gold nanoparticles using alginate: In vitro and in vivo assessment of its administration effects with swimming exercise on diabetic rats

Gold nanoparticles (AuNPs) have unique features that might lead to the development of a new class of diabetic medicines. AuNPs were biosynthesized utilizing sodium-alginate. UV-Vis-spectroscopy, Fourier transforms infrared, field emission scanning electron microscopy (FESEM), and energy dispersive X-ray were used to examine the particles. The potential of AuNPs for improving the diabetes condition was examined along with swimming in rats. FESEM image revealed the spherical morphology with an average particle size of 106.6 ± 20.8 nm. In the diabetic group, serum glucose, blood urea nitrogen (BUN), creatinine, cholesterol, and triglyceride (TG) levels were significantly higher than the control group. Low-density lipoprotein (LDL) was significantly higher and high-density lipoprotein (HDL) was significantly lower in the diabetic group compared to the control group. Malondialdehyde (MDA) levels were also significantly higher in the D group. However, in the groups treated with swimming and gold, these parameters were significantly improved. Specifically, serum-glucose, BUN, creatinine, cholesterol, and TG levels were significantly reduced, while LDL was significantly decreased in the diabetic + swimming + AuNPs group and HDL was significantly increased in the diabetic + AuNPs group. MDA levels were significantly decreased in the treated groups, and other antioxidants were significantly improved in the diabetic + swimming + AuNPs group. Catalase levels were also significantly improved in the D + gold group. It can be concluded that both AuNPs and swimming can decrease diabetic complications.

SIRT3 alleviates high glucose-induced chondrocyte injury through the promotion of autophagy and suppression of apoptosis in osteoarthritis progression

A growing amount of epidemiological evidence proposes diabetes mellitus (DM) to be an independent risk factor for osteoarthritis (OA). Sirtuin 3 (SIRT3), which is mainly located in mitochondria, belongs to the family of nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylases and is involved in the physiological and pathological processes of cell regulation. The aim of this study was to investigate the effects of SIRT3 on diabetic OA and underlying mechanisms in the prevention of type 2 DM (T2DM)-induced articular cartilage damage. High-fat and high-sugar diets combined with streptozotocin (STZ) injection were used for establishing an experimental T2DM rat model. The destabilization of medial meniscus (DMM) surgery was applied to induce the rat OA model. Primary rat chondrocytes were cultivated with a concentration of gradient glucose. Treatment with intra-articular injection of SIRT3 overexpression lentivirus was achieved in vivo, and intervention with SIRT3 knockdown was performed using siRNA transfection in vitro. High glucose content was found to activate inflammatory response, facilitate apoptosis, downregulate autophagy, and exacerbate mitochondrial dysfunction in a dose-dependent manner in rat chondrocytes, which can be deteriorated by SIRT3 knockdown. In addition, articular cartilage damage was found to be more severe in T2DM-OA rats than in DMM-induced OA rats, which can be mitigated by the intra-articular injection of SIRT3 overexpression lentivirus. Targeting SIRT3 is a potential therapeutic strategy for the alleviation of diabetic OA.

Fenugreek and Its Effects on Muscle Performance: A Systematic Review

Fenugreek extracts possess promising physiological and pharmacological properties in human and animal models. This review aims to provide a scientific and comprehensive analysis of the literature on the effects of fenugreek extracts on muscle performance. An extensive online search was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines. The main medical and scientific engines were searched for articles from May 1981 to May 2021 to capture all scientific studies focused on the effect of fenugreek on muscle and exercise or sport. Out of 81 studies acquired, six eligible randomized controlled trials (RCTs) were included in the qualitative analysis. Four RCTs observed that fenugreek supplementation had significantly improved muscle strength, repetitions to failure (muscle endurance), submaximal performance index, lean body mass, and reduced body fat. Among the remaining two trials, one reported the significant effect of fenugreek extracts on the rate of muscle glycogen resynthesis during post-exercise recovery; however, the other failed to do so. Those two trials were weak, with a minimal sample size (<10). Further, fenugreek glycoside supplementation with sapogenins and saponins reported substantial anabolic and androgenic activity, influencing testosterone levels and muscle performance. It was useful during eight weeks of resistance training without any clinical side effects. Fenugreek with creatine supplementation improved creatine uptake without the necessity of high carbohydrate intake. Hence, fenugreek extracts can be a helpful natural supplement and ergogenic aid for athletes. However, it is better to be aware of doping and liver and kidney damage before using the fenugreek supplement.

Therapeutic overexpression of miR-92a-2-5p ameliorated cardiomyocyte oxidative stress injury in the development of diabetic cardiomyopathy

Background

Diabetic cardiomyopathy (DCM) results from pathological changes in cardiac structure and function caused by diabetes. Excessive oxidative stress is an important feature of DCM pathogenesis. MicroRNAs (miRNAs) are key regulators of oxidative stress in the cardiovascular system. In the present study, we screened for the expression of oxidative stress-responsive miRNAs in the development of DCM. Furthermore, we aimed to explore the mechanism and therapeutic potential of miR-92a-2-5p in preventing diabetes-induced myocardial damage.

Methods

An experimental type 2 diabetic (T2DM) rat model was induced using a high-fat diet and low-dose streptozotocin (30 mg/kg). Oxidative stress injury in cardiomyocytes was induced by high glucose (33 mmol/L). Oxidative stress-responsive miRNAs were screened by quantitative real-time PCR. Intervention with miR-92a-2-5p was accomplished by tail vein injection of agomiR in vivo or adenovirus transfection in vitro.

Results

The expression of miR-92a-2-5p in the heart tissues was significantly decreased in the T2DM group. Decreased miR-92a-2-5p expression was also detected in high glucose-stimulated cardiomyocytes. Overexpression of miR-92a-2-5p attenuated cardiomyocyte oxidative stress injury, as demonstrated by increased glutathione level, and reduced reactive oxygen species accumulation, malondialdehyde and apoptosis levels. MAPK interacting serine/threonine kinase 2 (MKNK2) was verified as a novel target of miR-92a-2-5p. Overexpression of miR-92a-2-5p in cardiomyocytes significantly inhibited MKNK2 expression, leading to decreased phosphorylation of p38-MAPK signaling, which, in turn, ameliorated cardiomyocyte oxidative stress injury. Additionally, diabetes-induced myocardial damage was significantly alleviated by the injection of miR-92a-2-5p agomiR, which manifested as a significant improvement in myocardial remodeling and function.

Conclusions

miR-92a-2-5p plays an important role in cardiac oxidative stress, and may serve as a therapeutic target in DCM.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s11658-022-00379-9.

Protective effects of medicinal plant against diabetes induced cardiac disorder: A review

ETHNOPHARMACOLOGY RELEVANCE

Nowadays, there is an increase in global tendency to use medicinal plants as preventive and therapeutic agents to manage diabetes and its long-term complications such as cardiovascular disorders owing to their availability and valuable traditional background.

AIM OF STUDY

This review aims to introduce common medicinal plants, which have been demonstrated to have cardioprotective effects on diabetes and their mechanisms of action.

MATERIALS AND METHODS

Online literature databases, including Web of Sciences, PubMed, Science Direct, Scopus and Google Scholar were searched without date limitation by May 2020. The following keywords (natural products or medicinal plants or herbal medicine or herb or extract) and (diabetes or antidiabetic or hyperglycemic) and (cardiomyopathy or heart or cardioprotective or cardiac or cardio) were used, and after excluding non-relevant articles, 81 original English articles were selected.

RESULTS

The surveyed medicinal plants induced cardioprotective effects mostly through increasing antioxidant effects leading to attenuating ROS production as well as by inhibiting inflammatory signaling pathways and related cytokines. Moreover, they ameliorated the Na+/K + ATPase pump, the L-type Ca₂⁺ channel current, and the intracellular ATP. They also reduced cardiac remodeling and myocardial cell apoptosis through degradation of caspase-3, Bax, P53 protein, enhancement of Bcl-2 protein expression as well as downregulation of TGFβ1 and TNFα expression. In addition, the extracts improved cardiac function through increasing EF% and FS% as well as restoring hemodynamic parameters.

CONCLUSIONS

The reviewed medicinal plants demonstrated cardioprotective manifestations in diabetes through intervention with mechanisms involved in the diabetic heart to restore cardiovascular complications.

Nephroprotective effect of Artemisia herba alba aqueous extract in alloxan-induced diabetic rats

BACKGROUND AND AIM

In the present study, we investigate the phytochemical composition and the nephroprotective effects as well as the antioxidant properties of Artemisia herba alba aqueous extract in alloxan-induced experimental diabetes in rats.

EXPERIMENTAL PROCEDURE

Wistar rats were divided into four groups of seven rats each: Group I: Normal control (NC) received saline solution at 9‰ given by intraperitoneal way; Group II: Diabetic control (DC) received alloxan (150 mg/kg b.w) intraperitoneally; Group III: Normal control (NC + AHA) received saline solution at 9‰ and treated orally by AHA aqueous extract (400 mg/kg/b.w); Group IV: Diabetic control (DC + AHA) received alloxan solution (150 mg/kg b.w) intraperitoneally and treated by aqueous extract of AHA (400 mg/kg/b.w/day) orally after one week of alloxan administration. After 30 days, blood and tissue samples were collected for biochemical and histopathological analysis, respectively. Glomerular damage markers, including creatinine, serum urea, urine creatinine and urine urea levels were estimated. Creatinine clearance was also assessed. Oxidative stress parameters were assessed in the kidney homogenate.

RESULTS AND CONCLUSION

Alloxan-exposure resulted in significant increase in blood glucose and serum level of glomerular damage markers. The antioxidant enzyme activities were significantly downregulated associated with an increase in malondialdehyde (MDA) level over the baseline values. Artemisia herba alba aqueous extract supplementation significantly improved the studied parameters. In concluding, the results obtained suggests that Artemisia herbs-alba aqueous extract supplementation reduces alloxan-induced free radical generation, potentiates the antioxidant defense system and alleviates renal sensitivity to oxidative stress.

Mitigating effects of antioxidant properties of Artemisia herba alba aqueous extract on hyperlipidemia and oxidative damage in alloxan-induced diabetic rats

Chronic hyperglycemia and excess reactive oxygen species overproduced in diabetes were associated with oxidative stress, led to continuous injury and functions damage to different organs: eyes, kidneys, neural and cardiovascular system. The present study was undertaken to evaluate the protective effect of Artemisia herba alba (AHA) leaf powder against alloxane-induced oxidative damage in diabetic rats. Rats were randomly divided into four groups: Group I controls received saline solution 9%; Group II was treated with 150 mg alloxane/(kg body weight) administered by intraperitoneal. Rats of Group III have received saline solution and treated with 400 mg AHA/(kg body weight). Animals of Group IV were treated with alloxane and AHA. Alloxane exposure led to increased blood glucose, total cholesterol, triglycerides, malondialdehyde, and a decrease in the antioxidants enzymes activities (catalase, glutathione peroxidase and glutathione-S-transferase). Administration of AHA aqueous extract ameliorated these parameters. These results demonstrate that AHA ameliorates hyperglycemia, hyperlipidemia and oxidative damage in alloxan-induced diabetes in rats.

Quickly promoting angiogenesis by using a DFO-loaded photo-crosslinked gelatin hydrogel for diabetic skin regeneration

A desferrioxamine (DFO)-loaded photo-crosslinked gelatin hydrogel was used to reconstruct vessel network and prompt skin regeneration in diabetic wounds.