Southern Brazilian native fruit shows neurochemical, metabolic and behavioral benefits in an animal model of metabolic syndrome

Sustainable Intervention: Grape Pomace Flour Ameliorates Fasting Glucose and Mitigates Streptozotocin-Induced Pancreatic Damage in a Type 2 Diabetes Animal Model

Background/Objectives: Type 2 Diabetes Mellitus (T2DM) is characterized by hyperglycemia, increased risk of cardiovascular diseases, and oxidative imbalances. This study aimed to investigate the impact of dietary supplementations with 'Arinto' grape pomace flour (GPF) (WGPF) and 'Touriga Nacional' GPF (RGPF) in an animal model of T2DM. Methods: T2DM was induced by a high-fat diet (HFD) for 28 days and a single dose of streptozotocin (STZ) (35 mg/kg) on the 21st day. Forty adult male Wistar rats were divided into five groups: Control (CT), T2DM, T2DM + Metformin (250 mg/kg), T2DM + 10% 'Arinto' GPF (WGPF), and T2DM + 10% 'Touriga Nacional' GPF (RGPF). On the 21st day of the experimental protocol, animals were submitted to an oral glucose tolerance test. An oral glucose tolerance test, oxidative stress parameters, biochemical analysis, and pancreas histological analyses were performed. Results: T2DM impaired glucose tolerance, elevated serum triglycerides and cholesterol, increased oxidative damage in the liver, and induced pancreatic histological abnormalities. However, supplementation with WGPF and RGPF demonstrated positive effects, mitigating glycemic and lipid disruptions, ameliorating oxidative stress, and protecting pancreatic Islets β-cells. Conclusions: Our findings highlight the protective effects of WGPF and RGPF in the adverse impacts of T2DM. Additionally, our study emphasizes the innovative use of grape pomace, a winemaking by-product, promoting sustainability by transforming waste into functional foods with significant health benefits.

Psidium cattleianum fruit extract prevents systemic alterations in an animal model of type 2 diabetes mellitus: comparison with metformin effects

Objective: In this study, we aimed to determine the role of Psidium cattleianum extract (PCE) and compare its effects with those of metformin (Met) in an animal model with type 2 diabetes mellitus (T2DM).Methods: T2DM was induced in rats using a high-fat diet (HFD), followed by a single dose of streptozotocin (STZ). Met and PCE were administered intragastrically once a day throughout the experiment, and their effects on biochemical, inflammatory, oxidative, and histological parameters were evaluated.Results: Met and PCE prevented the increase in serum levels of glucose, total cholesterol (TC), triacylglycerol (TG), very low-density lipoprotein (VLDL) and interleukin-6 (IL-6) induced by T2DM, and restored redox homeostasis in the liver and brain. Met increased the serum levels of anti-inflammatory cytokine and interleukin-10 (IL-10). Furthermore, both treatments restored the liver and pancreas from marked cellular disorganisation, vacuolisation, and necrosis, with PCE being more effective than Met in recovering histological changes.Conclusion: PCE is a promising agent for the prevention of T2DM complications.

Momordica charantia (bitter melon) efficacy and safety on glucose metabolism in Korean prediabetes participants: a 12-week, randomized clinical study

This study was performed to investigate the effects of bitter melon extract (BME) on glucose metabolism, insulin resistance, and various metabolic parameters of participants with prediabetes. A 12-week randomized placebo-controlled clinical study was conducted with prediabetic patients. A total of 76 participants were randomly assigned to initiate the study. In the final analysis, 33 and 32 subjects were included in the BME and placebo groups, respectively. Results showed that 75 g oral glucose tolerance test (OGTT) blood glucose level decreased in BME group after 12 weeks. The glucose level after 30 min of glucose ingestion decreased significantly. The glucagon level in the BME group after 12 weeks significantly decreased 120 min after 75 g OGTT. These results suggested that bitter melon exhibits glucose-lowering effects through suppression of glucagon levels in people with prediabetes.

Extract of Calyces from Physalis peruviana Reduces Insulin Resistance and Oxidative Stress in Streptozotocin-Induced Diabetic Mice

Diabetes mellitus is a metabolic disorder mainly characterized by obesity, hyperglycemia, altered lipid profile, oxidative stress, and vascular compromise. Physalis peruviana is a plant used in traditional Colombian medicine for its known activities of glucose regulation. This study aimed to evaluate the anti-diabetic activity of the butanol fraction from an extract of Physalis peruviana calyces in two doses (50 mg/kg and 100 mg/kg) in induced type 2 diabetic mice. Blood glucose levels were evaluated once a week, demonstrating that a dose of 100 mg/kg resulted in greater regulation of blood glucose levels in mice throughout the experiment. The same overall result was found for the oral glucose tolerance test (OGTT) and the homeostatic model assessment for insulin resistance (HOMA- IR). The lipid profile exhibited improvement compared to the non-treated group, a dose of 100 mg/kg having greater protection against oxidative stress (catalase, superoxide dismutase, and malondialdehyde levels). Histopathological findings in several tissues showed structure preservation in most of the animals treated. The butanol fraction from Physalis peruviana at 100 mg/kg showed beneficial results in improving hyperglycemia, lipidemia, and oxidative stress status, and can therefore be considered a beneficial coadjuvant in the therapy of diabetes mellitus.

Brazilian native fruit extracts act as preventive agents modulating the purinergic and cholinergic signalling in blood cells and serum in a rat model of metabolic syndrome

In this study, we evaluated the effects of native fruit extracts on inflammatory and thromboregulatory parameters in animal model of metabolic syndrome (MetS) induced by highly palatable diet (HPD). Rats were divided into 4 experimental groups: standard chow, HPD, HPD and Psidium cattleianum extract, and HPD and Eugenia uniflora extract. HPD increased serum interleukin-6 (IL-6) levels. On the other hand, this change was prevented by extracts. HPD decreased NTPDase activity in lymphocytes and platelets and 5'-nucleotidase in platelets. Treatment with extracts prevented these changes. An increase in adenosine deaminase (ADA) activity was prevented by E. uniflora in lymphocytes and serum of rats. Fruit extracts prevented the increase in the activity of acetylcholinesterase (AChE) in lymphocytes and butyrylcholinesterase (BuChE) in serum induced by the HPD. Brazilian native fruit extracts have anti-inflammatory and antithrombotic effects, demonstrating therapeutic potential in the prevention of complications associated with MetS.

Diagnostic Criteria for Metabolic Syndrome in Diet-Induced Rodent Models: A Systematic Review

BACKGROUND

Thousands of publications in recent years have addressed the induction of metabolic syndrome (MetS) in rodents. However, the criteria and the reference values for diagnosing this disease have not been defined.

OBJECTIVE

Our main objective was to carry out a systematic review to gather evidence about the criteria for biochemical and anthropometric parameters in which scientific studies have relied on to report that rats developed MetS from a previous dietary manipulation.

METHODS

We compiled characteristics and findings of diet-induced MetS with high-fat, high-carbohydrate, high-fat/high-carbohydrates, and cafeteria diet from PubMed and Science Direct databases published in the last 5 years.

RESULTS

The results on the principal determinants for the syndrome, published in the reviewed articles, were chosen to propose reference values in the rat models of food induction.

CONCLUSION

The values obtained will serve as reference cut-of points in the development of the disease; in addition, the compilation of data will be useful in planning and executing research protocols in animal models.

Extraction and characterization of phytochemical compounds from araçazeiro (Psidium cattleianum) leaf: Putative antioxidant and antimicrobial properties

Underexplored species have phytochemical potential for pharmacological and nutraceutical applications. The fruits of such species, including aracá (Psidium cattleianum Sabine), are rich in specialized metabolites with putative antioxidant and antimicrobial activity; therefore, the leaves of these species are also a potential source of bioactive compounds. In this study, araçazeiro leaves were extracted using an aqueous infusion (Al) and a pressurized liquid extraction system with water (PLE-W), ethanol (PLE-E), and 1:1 water:ethanol ratio combination (PLE-W:E). PLE-W:E yielded a greater diversity of extracted compounds. Nonetheless, all extracts showed inhibitory activity against pathogenic Gram-positive and Gram-negative bacteria and antioxidant activity in the in vitro thiobarbituric acid reactive substances (TBARS) and reactive oxygen species (ROS) assays with rat brain and yeast model systems. Thus, araçazeiro leaves can be exploited as a promising source of bioactive compounds.

Natural Compounds as Beneficial Antioxidant Agents in Neurodegenerative Disorders: A Focus on Alzheimer's Disease

The positive role of nutrition in chronic neurodegenerative diseases (NDs) suggests that dietary interventions represent helpful tools for preventing NDs. In particular, diets enriched with natural compounds have become an increasingly attractive, non-invasive, and inexpensive option to support a healthy brain and to potentially treat NDs. Bioactive compounds found in vegetables or microalgae possess special properties able to counteract oxidative stress, which is involved as a triggering factor in neurodegeneration. Here, we briefly review the relevant experimental data on curcuminoids, silymarin, chlorogenic acid, and compounds derived from the microalga Aphanizomenon flos aquae (AFA) which have been demonstrated to possess encouraging beneficial effects on neurodegeneration, in particular on Alzheimer's disease models.