Yacon (Smallanthus sonchifolius) Leaf Extract Attenuates Hyperglycemia and Skeletal Muscle Oxidative Stress and Inflammation in Diabetic Rats

Exploratory review on the evidence of Andean crops with hypoglycemic effect and their bioactive components

Diabetes is a chronic disease that affects several people around the world. Some domesticated crops in South America have been reported to be a promising source of bioactive compounds with possible hypoglycemic effects. In this review we aimed to explore and synthesize the existing evidence in the scientific literature on the hypoglycemic effect of Andean crops and their bioactive components. We included different types of primary studies from three databases (Scopus, Pubmed and Web of Science) during June 2023, without restrictions, by means of controlled and uncontrolled language, according to the PICO strategy. We found 30 studies conducted between 2005 and 2022 that reported a hypoglycemic effect, through enzymatic inhibition in in vitro studies and significant glucose reduction in preclinical studies and clinical trials. This effect was attributed to different bioactive components that were identified with independent mechanisms related to glucose reduction and enzymatic inhibition. The most commonly used cultures were Smallanthus sonchifolius (9/30), Lupinus mutabilis (5/30) and Solanum tuberosum (4/30). The hypoglycemic effect was assigned to bioactive components such as polyphenols, flavonoids, phenolic acid subclasses, fructans, alkaloids, hydrolysates, anthocyanins and dietary fiber. Despite encouraging results from different types of studies, further research on their mechanisms of action, their efficacy compared to conventional treatments and their long-term safety is required for these to be considered safe and effective treatments.

Myths and beliefs about insulin therapy in patients with diabetes mellitus and their family caregivers from a hospital in northern Peru, 2020

OBJECTIVE.

To analyze and explore the myths and beliefs about insulin therapy in patients with diabetes mellitus and their family caregivers from a general hospital in northern Peru in 2020.

MATERIALS AND METHODS.

This qualitative study used a thematic analysis model, following the interpretative paradigm. Sociodemographic and clinical data were obtained from medical records. Patients with diabetes that used some type of insulin for at least three months prior to the study were interviewed, as well as their family caregivers. Patients participated in a focus group and in-depth interviews; family caregivers participated only in in-depth interviews.

RESULTS.

Twelve patients with diabetes (11 with type 2 diabetes mellitus) were included; six in the focus group and six in the in-depth interviews. Seven family caregivers were included. After analysis, we obtained four categories: 1) beliefs related to starting insulin treatment: treatment of choice after failure of other drugs, cures diabetes, regulates sugar, fear of injectables; 2) beliefs related to treatment adherence: decompensation for not using insulin, insulin is necessary to live; 3) beliefs related to alternative therapies and cost: use of alternative therapies, high cost of insulin; and 4) myths related to the use of insulin: generates dependence, dependence for insulin administration, negative effects of insulin.

CONCLUSIONS.

The beliefs and myths of patients treated with insulin arise from the beginning of treatment, remain throughout the course of treatment, and are often reinforced by the worldview of family members.

Antioxidant and anti-inflammatory properties of gamma- oryzanol attenuates insulin resistance by increasing GLUT- 4 expression in skeletal muscle of obese animals

BACKGROUND

Skeletal muscle is the most important organ for whole-body glucose homeostasis. However, it has been suggested that obesity-related inflammation could be involved in insulin resistance and diabetes mellitus type 2 (DM2) development due several mechanisms, among them, the reduced expression of the glucose transporter type 4 (GLUT-4). Gamma-oryzanol (γOz) is a compound present in the whole grain of rice that presents anti-inflammatory and antioxidant activities. The aim of this study was to verify if the effect antioxidant and anti-inflammatory of yOz attenuate insulin resistance in skeletal muscle of obese rats by increasing GLUT- 4 expression.

METHODS

Male Wistar rats (±187 g) were initially randomly distributed into 2 experimental groups (control, n = 6, and high sugar-fat diet (HSF), n = 12) for 20 weeks. At week 20th of this study, once obesity and insulin resistance were detected in the HSF group, animals were divided to begin the treatment with γOz or continue receiving HSF for 10 more weeks. At the end it was analyzed nutritional, metabolic, inflammatory and oxidative stress parameters and GLUT-4 protein expression.

RESULTS

The treatment improved insulin resistance, reduced inflammation, increased antioxidant response and GLUT-4 expression.

CONCLUSION

It is possible to conclude that the antioxidant and anti-inflammatory activity of yOz attenuates insulin resistance by increasing GLUT-4 expression in skeletal muscle of obese animals.

Use of Chlorogenic Acid against Diabetes Mellitus and Its Complications

Chlorogenic acid (CA) is a phenolic compound commonly found in human plant-based diets. CA is the main component of many traditional Chinese medicine preparations, and in recent years, it has been found to have hypoglycemic, hypolipidemic, anti-inflammatory, antioxidant, and other pharmacological properties. Specifically, CA relieves the effects of, and prevents, diabetes mellitus (DM). In addition, CA is also beneficial against complications arising from DM, such as diabetic nephropathy (DN), diabetic retinopathy (DR), and diabetic peripheral neuropathy (DPN). Herein, we review the use of CA in the prevention and treatment of DM and its complications, providing a background for further research and medical uses.

A Sustainable Wholesome Foodstuff; Health Effects and Potential Dietotherapy Applications of Yacon

A sustainable food supply is an ever-growing public and planetary health concern influenced by food culture, food practices, and dietary patterns. Globally, the consumption of plant foods that offer physiological and biochemical benefits is increasing. In recent years, products made from yacon (Smallanthus sonchifolius) tubers and leaves, e.g., in the form of syrup, powder, and herbal tea, have steadily emerged with scientific evidence to validate their possible health claims. Yacon was introduced to New Zealand in 1966, and its products can now be produced on a commercial scale. This paper reviews literature published mainly in the last 10 years concerning the health-related properties of yacon as a wholesome foodstuff and its bioactive components, e.g., fructooligosaccharides. Literature was sourced from Web of Science, PubMed, EBSCO Health, and Google Scholar up to June 2019. The potential markets for yacon in the field of food technology and new dietotherapy applications are discussed. Furthermore, the unique features of New Zealand-produced yacon syrup are introduced as a case study. The paper explores the scientific foundation in response to the growing public interest in why and how to use yacon.

Recovery of Cardiac Remodeling and Dysmetabolism by Pancreatic Islet Injury Improvement in Diabetic Rats after Yacon Leaf Extract Treatment

Yacon (Smallanthus sonchifolius) is a native Andean plant rich in phenolic compounds, and its effects on dysmetabolism and cardiomyopathy in diabetic rats was evaluated. The rats (10/group) were allocated as follows: C, controls; C + Y, controls treated with Yacon leaf extract (YLE); DM, diabetic controls; and DM + Y, diabetic rats treated with YLE. Type 1 diabetes (T1DM) was induced by the administration of streptozotocin (STZ; 40 mg⁻¹/kg body weight, single dose, i.p.), and treated groups received 100 mg/kg body weight YLE daily via gavage for 30 d. The YLE group shows an improvement in dysmetabolism and cardiomyopathy in the diabetic condition (DM versus DM + Y) promoting a significant reduction of glycemia by 63.39%, an increase in insulin concentration by 49.30%, and a decrease in serum triacylglycerol and fatty acid contents by 0.39- and 0.43-fold, respectively, by ameliorating the pancreatic islet injury, as well as increasing the activity of the antioxidant enzymes (catalase, superoxide dismutase, and glutathione peroxidase) and decreasing the fibrosis and cellular disorganization in cardiac tissue. The apparent benefits of YLE seem to be mediated by ameliorating dysmetabolism and oxidative stress in pancreatic and cardiac tissues.