Pouteria torta epicarp as a useful source of α-amylase inhibitor in the control of type 2 diabetes

Pouteria spp. fruits: Health benefits of bioactive compounds and their potential for the food industry

The Sapotaceae family encompasses the genus Pouteria spp., comprising approximately 1,250 species of fruits cherished by consumers for their delightful assortment and flavors. Over the years, extensive research has been devoted to exploring the natural bioactive compounds present in these fruits, with the primary goal of preventing and/or mitigating the risk of degenerative diseases. Despite their widespread popularity in numerous countries, the chemistry, nutritional content, and biological potential of these fruits remain relatively unexplored. This comprehensive review aims to shed light on the principal volatile and non-volatile chemical components found in Pouteria fruits, which present notable antioxidant properties. By doing so, a broad perspective on the current trends in characterizing these compounds and their potential applications were provided, as well as the associated health benefits. Additionally, the prospects and potential applications of Pouteria fruits in the food industry were explored herein.

New Therapeutic Strategies for Obesity and Its Metabolic Sequelae: Brazilian Cerrado as a Unique Biome

Brazil has several important biomes holding impressive fauna and flora biodiversity. Cerrado being one of the richest ones and a significant area in the search for new plant-based products, such as foods, cosmetics, and medicines. The therapeutic potential of Cerrado plants has been described by several studies associating ethnopharmacological knowledge with phytochemical compounds and therapeutic effects. Based on this wide range of options, the Brazilian population has been using these medicinal plants (MP) for centuries for the treatment of various health conditions. Among these, we highlight metabolic diseases, namely obesity and its metabolic alterations from metabolic syndrome to later stages such as type 2 diabetes (T2D). Several studies have shown that adipose tissue (AT) dysfunction leads to proinflammatory cytokine secretion and impaired free fatty acid (FFA) oxidation and oxidative status, creating the basis for insulin resistance and glucose dysmetabolism. In this scenario, the great Brazilian biodiversity and a wide variety of phytochemical compounds make it an important candidate for the identification of pharmacological strategies for the treatment of these conditions. This review aimed to analyze and summarize the current literature on plants from the Brazilian Cerrado that have therapeutic activity against obesity and its metabolic conditions, reducing inflammation and oxidative stress.

Role and mechanism of fruit waste polyphenols in diabetes management

Among various diseases in humans, diabetes is one of the most complicated disorders resulting either from the malfunctioning of β cells, causing a poor discharge of insulin from them, or poor functioning of the liberated insulin. A wide array of chemical compounds so-called secondary metabolites are present in plants. These phytochemicals are produced as by-products of metabolism and play a key role in plant protection. However, in humans, they offer several beneficial functions. Polyphenols are an important class of phytochemicals and apart from fruits, they are also found in their major wastes mainly including the peel, pomace, and seed. The current review is aimed to focus on the potential sources, distribution, and extraction/isolation of polyphenols from major fruit wastes along with highlighting their medicinal and therapeutic benefits, especially in the management of diabetes.

Anti-obesity, anti-hyperglycaemic, anti-antipyretic and analgesic activities of Globularia alypum extracts

OBJECTIVES

The aim of this study is to evaluate the anti-obesity, anti-hyperglycaemic, analgesic and antipyretic activities of Globularia alypum (GA).

MATERIALS AND METHODS

GA methanol and water extracts (GAME, GAWE) were administered to high-fat-high-glucose diet (HFFD) rats.

RESULTS

This study showed that GAME exhibited the highest antioxidant, anti-α-amylase and anti-lipase activities, with half inhibitory concentration (IC50) values 0.067, 1.05 and 2.97 mg/ml respectively. In HFFD rats, the administration of GAME inhibited lipase activity by 36, 37 and 30% in the intestine, pancreas and serum, respectively, reduced body weight by 17.7% and modulated lipid profile. In addition, administration of GAME to HFFD-rats decreased α-amylase activity, improved glucose level and protected liver function. Furthermore, the administration of GA extracts to rats revealed antipyretic (reduction in writhing by 64%) and analgesic (decrease of temperature by 1.11 °C) activities.

CONCLUSION

This study showed that GA extracts exhibited an anti-obesity, anti-hyperglycaemia, anti-pyretic and analgesic activities.

White common bean extract remodels the gut microbiota and ameliorates type 2 diabetes and its complications: A randomized double-blinded placebo-controlled trial

OBJECTIVE

Excessive carbohydrate intake is a high risk factor for increased morbidity of type 2 diabetes (T2D). A novel regimen for the dietary care of diabetes that consists of a highly active α-amylase inhibitor derived from white common bean extract (WCBE) and sufficient carbohydrates intake was applied to attenuate T2D and its complications. Furthermore, the role of gut microbiota in this remission was also investigated.

METHODS

We conducted a 4-month randomized double-blinded placebo-controlled trial. During the intense intervention period, ninety subjects were randomly assigned to the control group (Group C) and WCBE group (Group W). Subjects in Group C were supplemented with 1.5 g of maltodextrin as a placebo. Subjects in Group W took 1.5 g of WCBE half an hour before a meal. Fifty-five participants continued the maintenance intervention receiving the previous dietary intervention whereas less frequent follow-up. The variation in biochemical, vasculopathy and neuropathy indicators and the structure of the fecal microbiota during the intervention was analyzed.

RESULT

Glucose metabolism and diabetic complications showed superior remission in Group W with a 0.721 ± 0.742% decline of glycosylated hemoglobin after 4 months. The proportion of patients with diabetic peripheral neuropathy (Toronto Clinical Scoring System, TCSS ≥ 6) was significantly lower in Group W than in Group C. Both the left and right sural sensory nerve conduction velocity (SNCV-left sural and SNCV-right sural) slightly decreased in Group C and slightly increased in Group W. Additionally, the abundances of Bifidobacterium, Faecalibacterium and Anaerostipes were higher in Group W, and the abundances of Weissella, Klebsiella, Cronobacter and Enterobacteriaceae_unclassified were lower than those in Group C at month 2. At the end of month 4, Bifidobacterium remained more abundant in Group W.

CONCLUSION

To our knowledge, this is the first report of improvement to diabetes complications by using a dietary supplement in such a short-term period. The enrichment of SCFA-producing bacteria might be responsible for the attenuation of T2D and its complications.

CLINICAL TRIAL REGISTRATION NUMBER

http://www.chictr.org.cn/edit.aspx?pid=23309&htm=4, identifier ChiCTR-IOR-17013656.

In Silico Approaches to Identify Polyphenol Compounds as α-Glucosidase and α-Amylase Inhibitors against Type-II Diabetes

Type-II diabetes mellitus (T2DM) results from a combination of genetic and lifestyle factors, and the prevalence of T2DM is increasing worldwide. Clinically, both α-glucosidase and α-amylase enzymes inhibitors can suppress peaks of postprandial glucose with surplus adverse effects, leading to efforts devoted to urgently seeking new anti-diabetes drugs from natural sources for delayed starch digestion. This review attempts to explore 10 families e.g., Bignoniaceae, Ericaceae, Dryopteridaceae, Campanulaceae, Geraniaceae, Euphorbiaceae, Rubiaceae, Acanthaceae, Rutaceae, and Moraceae as medicinal plants, and folk and herb medicines for lowering blood glucose level, or alternative anti-diabetic natural products. Many natural products have been studied in silico, in vitro, and in vivo assays to restrain hyperglycemia. In addition, natural products, and particularly polyphenols, possess diverse structures for exploring them as inhibitors of α-glucosidase and α-amylase. Interestingly, an in silico discovery approach using natural compounds via virtual screening could directly target α-glucosidase and α-amylase enzymes through Monte Carto molecular modeling. Autodock, MOE-Dock, Biovia Discovery Studio, PyMOL, and Accelrys have been used to discover new candidates as inhibitors or activators. While docking score, binding energy (Kcal/mol), the number of hydrogen bonds, or interactions with critical amino acid residues have been taken into concerning the reliability of software for validation of enzymatic analysis, in vitro cell assay and in vivo animal tests are required to obtain leads, hits, and candidates in drug discovery and development.

A study on nutritional and functional study properties of Mayan plant foods as a new proposal for type 2 diabetes prevention

Mayan communities cultivate a great variety of plant foods that could be of interest due to their nutritional and functional potential. The aim of this study was to evaluate the nutritional value, glycemic index (GI), total phenol content (TPC), and total flavonoid content (TFC), and in vitro antioxidant and antidiabetic activity of 24 plant foods of a Mayan community from the Yucatan Peninsula. Multivariate statistical analysis indicated that Psidium guajava L. (fruit), Cucurbita moschata (vegetable), Raphanus sativus L. (tuber), Brassica oleracea var. capitata L. (leaf), and Bixa orellana L. (seed) had the highest nutritional and functional value for each plant food group. Principal component analysis suggested that TFC is a key feature to select plant foods with antidiabetic potential. Mayan plant foods have nutritional and functional properties that can be used in the development of a new proposal aimed at preventing type 2 diabetes.

Phenolic content, antioxidant capacity, and α-amylase and α-glucosidase inhibitory activities of Dimocarpus longan Lour

The aim of this study was to compare the phenolic compound profiles and antioxidant capacities of eight varieties of longan (Dimocarpus longan Lour.) planted in the middle and upper Yangtze River area. The total polyphenols content (TPC) and total flavonoids content (TFC) of dried longan pulp ranged from 1.07 ± 0.05 to 1.22 ± 0.05 mg gallic acid equivalents/g and 0.25 ± 0.07 to 0.87 ± 0.14 mg rutin equivalents/g. UHPLC-QqQ-MS/MS analysis revealed 12 individual polyphenol compounds in longan. The Fuwan8, Dongliang and FD97 varieties showed the strongest DPPH scavenging activity (IC₅₀ of 1.03 g/mL). The highest ABTS⁺ scavenging activity was found in the Dongliang. In the enzyme assays, the Fuwan8 and Dongliang varieties demonstrated maximum α-amylase and α-glucosidase inhibition activities, with values of 97.56 and 88.58%, respectively. The principal component analysis indicated that the Rongyu8 and Songfengben cultivars have nearly analogous polyphenol compounds.

Design and evaluation of chalconeimine derivatives as α-amylase inhibitors

Alpha-amylase is a known target for type II diabetes. Therefore, it is of interest to design α-amylase inhibitors based on hydrazone scaffold. The structure of these hybrids was confirmed by spectroscopic analysis (IR, 1H-and 13C NMR). All the compounds have potential inhibitory properties as shown by in vitro α-amylase inhibition activity. The compound 5-((1Z,3Z)-3-(benzo[d][1,3]dioxol-5-yl)-3-((2-chloropyridin-3- yl)imino)prop-1-en-1-yl)-2-(difluoromethoxy)phenol(4a) in 100 µg/mL concentration showed a high inhibition of 85.23%. In vitro α-amylase inhibition was further supported by docking studies of compound against the active site of pig pancreatic α-amylase (PDB ID: 3L2M). Docking studies revealed that the bonding interactions found between the compound and human pancreatic α-amylase are similar to those responsible for α-amylase inhibition by acarbose.

Fighting Type-2 Diabetes: Present and Future Perspectives

BACKGROUND

Type-2 diabetes mellitus accounts for 80-90% of diabetic patients. So far, the treatment of diabetes mainly aims at elevating insulin level and lowering glucose level in the peripheral blood and mitigating insulin resistance. Physiologically, insulin secretion from pancreatic β cells is delicately regulated. Thus, how insulin-related therapies could titrate blood glucose appropriately and avoid the occurrence of hypoglycemia remains an important issue for decades. Similar question is addressed on how to attenuate vascular complication in diabetic subjects.

METHODS

We overviewed the evolution of each class of anti-diabetic drugs that have been used in clinical practice, focusing on their mechanisms, clinical results and cautions.

RESULTS

Glucagon-like peptide-1 receptor agonists stimulate β cells for insulin secretion in response to diet but not in fasting stage, which make them superior than conventional insulinsecretion stimulators. DPP-4 inhibitors suppress glucagon-like peptide-1 degradation. Sodium/ glucose co-transporter 2 inhibitors enhance glucose clearance through urine excretion. The appearance of these new drugs provides new information about glycemic control. We update the clinical findings of Glucagon-like peptide-1 receptor agonists, DPP-4 inhibitors and Sodium/glucose cotransporter 2 inhibitors in glycemic control and the risk or progression of cardiovascular disease in diabetic patients. Stem cell therapy might be an alternative tool for diabetic patients to improve β cell regeneration and peripheral ischemia. We summarize the clinical results of mesenchymal stem cells transplanted into patients with diabetic limb and foot.

CONCLUSION

A stepwise intensification of dual and triple therapy for individual diabetic patient is required to achieve therapeutic target.

Acylated Aminooligosaccharides with Inhibitory Effects against α-Amylase from Streptomyces sp. HO1518

Five new acylated aminooligosaccharides (1–5), together with one known related analogue (6), were isolated from Streptomyces sp. HO1518. Their structure was identified by extensive spectroscopic analysis, including 1D and 2D NMR data and high resolution electrospray ionization mass spectrometry (HRESIMS), and by comparison with those reported in the literature. All of the new compounds showed more promising porcine pancreatic α-amylase (PPA) inhibitory activities than the clinical drug acarbose, indicating them as potential pharmaceutical drug leads toward type II diabetes.