Antioxidative and Anti-inflammatory Effects of Plant-derived Hypoglycemic Medicines: An In vivo/In vitro Systematic Review.

BACKGROUND: The activation of oxidative stress and inflammatory conditions has been associated with acceleration in diabetes (DM) onset and complications. Despite various anti-DM medications, there is a growing trend to discover inexpensive and effective treatments with low adverse effects from plants as one of the promising sources for drug development. OBJECTIVE: This study aimed to systematically investigate the simultaneous anti-inflammatory and antioxidant effects of plant-derived hypoglycemic medicines in diabetic experimental models. METHODS: The search terms consisted of "diabetes", "herbal medicine", "antioxidant", "Inflammatory biomarker", and their equivalents among PubMed, Scopus, Web of Science, and Cochrane Library databases up to 17 August 2021. RESULTS: Throughout the search of databases, 201 eligible experimental studies were recorded. The results showed that the most commonly assessed inflammatory and oxidative stress biomarkers were tumor necrosis factor (TNF)-α, interleukin (IL) 6, IL-1ß, IL-10, malondialdehyde (MDA), and nitric oxide (NO). The activity of antioxidant enzymes, including superoxide dismutase (SOD), glutathione (GSH), and catalase (CAT) were assessed in the present review. Among herbal treatments, Trigonella foenum-graecum L., Centella asiatica (L.) Urb., Vitis vinifera L., and Moringa oleifera Lam. were most commonly used for diabetic complications. Due to the dispersion of the treatments, meta-analysis was not applicable. CONCLUSION: Our findings showed that the application of different plant-derived hypoglycemic treatments in animal models improved diabetes and its complications, as well as modulated concomitant inflammatory and oxidative stress biomarkers. These findings suggest that plant-based antidiabetic medicines and food supplements have the potential to manage diabetes and its complications.

Meta-analysis of the anti-oxidative and anti-inflammatory effects of hypoglycaemic plant-derived medicines.

BACKGROUND: The pivotal role of oxidative stress and inflammation in the pathophysiology of type 2 diabetes mellitus (T2DM) has been firmly established. However, the evidence concerning hypoglycaemic medicinal plants' antioxidant and anti-inflammatory effects remains inconclusive due to inconsistencies in prior studies. To address this gap, our study aims to perform a comprehensive systematic review and meta-analysis of randomized controlled trials (RCTs) to consolidate previous research findings in this field. METHODS: We conducted a comprehensive search in the PubMed, Web of Science, Embase, Cochrane Library, and Scopus databases to identify relevant English randomized controlled trials (RCTs). Our study adhered to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. All eligible studies that evaluated concurrently the antioxidative and anti-inflammatory effects of hypoglycaemic plant-derived supplements on type 2 diabetes mellitus (T2DM) were included in the meta-analysis. The meta-analysis itself was carried out using both fixed and random effects models to synthesize the findings from the selected studies. RESULTS: Our study included 47 trials with a total of 2636 participants, both male and female, aged between 20 and 79 years, diagnosed with prediabetes, type 2 diabetes mellitus (T2DM), or metabolic syndrome. The meta-analysis revealed that plant-derived treatments, compared to placebos or other medicines, significantly improved oxidative stress (SMD = - 0.36, 95% CI - 0.64 to - 0.09), inflammation (SMD = - 0.47, 95% CI - 0.63 to - 0.31), total antioxidant capacity (SMD = 0.46, 95% CI 0.16-0.75), and antioxidant enzyme activity (SMD = 1.80, 95% CI 1.26-2.33). The meta-regression analysis showed that treatment duration exceeding 8 weeks significantly impacted the heterogeneity of the oxidative stress data. CONCLUSIONS: Several hypoglycaemic plant-based treatments appear to positively affect T2DM patients by concurrently lowering oxidative stress and inflammatory indicators and boosting antioxidant enzyme activity. CLINICAL TRAIL REGISTRY: PROSPERO ID: CRD42021226147.

The high-intensity interval training (HIIT) and curcumin supplementation can positively regulate the autophagy pathway in myocardial cells of STZ-induced diabetic rats.

OBJECTIVE: Targeting autophagy is a new therapeutic strategy for the complications of diabetes,such as diabetic cardiomyopathy (DCM). During diabetes, increased or insufficient autophagic activity causes aberrations in cellular homeostasis. Regarding the conflicting and unclear results regarding the effect of HIIT and curcumin supplementation on the expression of genes associated to autophagy, this study aimed to assess whether 4-week high-intensity interval training (HIIT) and curcumin supplementation are able to influence the expression of autophagy-related genes in myocardial cells of diabetic rats. METHODS: In an experimental design, 24 male Wistar rats were randomly divided into 4 groups: non-diabetic control (NC), diabetic control (DC), diabetes + HIIT (D + HIIT), and diabetes + curcumin (D + CU). After HIIT program and curcumin treatment, the genes expression of autophagy pathway were assessed in the myocardium by real-time PCR Tanique. RESULTS: The results indicated that the expression levels of ATG1, Beclin1, ATG5, and LAMP-2 genes were significantly reduced in the DC group compared to the NC group (p < 0.001). Following 4-week HIIT, the expression of Beclin1, ATG-5, and LAMP-2 improved considerably compared to the DC group (p < 0.001, p < 0.001, and p < 0.05, respectively). In addition, after 4 weeks of curcumin supplementation, the expression levels of ATG-5 and Beclin-1 were significantly improved compared to the DC group (p < 0.001, p < 0.05, respectively). It seems HIIT and curcumin supplementation can be an effective approach for inducing autophagy and improving cardiac function in DCM rats.However, HIIT seems more effective than curcumin in this regard.

Antioxidative hypoglycemic herbal medicines with in vivo and in vitro activity against C-reactive protein; a systematic review.

BACKGROUND: Inflammation is a double-edged sword in the pathophysiology of chronic diseases, such as type 2 diabetes mellitus (T2DM). The global rise in the prevalence of T2DM in one hand, and poor disease control with currently-available treatments on the other hand, along with an increased tendency towards the use of natural products make scientists seek herbal medicines for the management of diabetes and its complications by reducing C-reactive protein (CRP) as an inflammatory marker. PURPOSE: To systematically review the literature to identify the efficacy of various medicinal plants with antioxidative and anti-inflammatory properties considering their effect on CRP in animal models of T2DM. STUDY DESIGN: systematic review. METHODS: Electronic databases including PubMed, Scopus, Web of Science and Cochran Library were searched using the search terms "herbal medicine", "diabetes", "c-reactive protein", "antioxidants" till August 2021. The quality of evidence was assessed using the Systematic Review Centre for Laboratory animal Experimentation (SYRCLE's) tool. The study protocol was registered in PROSPERO with an ID number CRD42020207190. A manual search to detect any articles not found in the databases was also made. The identified studies were then critically reviewed and relevant data were extracted and summarized. RESULTS: Among total of 9904 primarily-retrieved articles, twenty-three experimental studies were finally included. Our data indicated that numerous herbal medicines, compared to placebo or hypoglycemic medications, are effective in treatment of diabetes and its complications through decreasing CRP concentrations and oxidative stresses levels. Medicinal plants including Psidium guajava L., Punica granatum L., Ginkgo biloba L., Punica granatum L., Dianthus superbusn L.. Moreover, Eichhornia crassipes (Mart.) Solms, Curcuma longa L., Azadirachta indica A. Juss., Morus alba L., and Ficus racemosa L. demonstrated potential neuroprotective effects in animal models of diabetes. CONCLUSION: Hypoglycemic medicinal plants discussed in this review seem to be promising regulators of CRP, and oxidative stress. Thus, these plants are suitable candidates for management of diabetes' complications. Nevertheless, further high-quality in vivo studies and clinical trials are required to confirm these effects.