Polysaccharides from Portulaca oleracea L. regulated insulin secretion in INS-1 cells through voltage-gated Na+ channel

Anti-obesity and anti-diabetic bioactive peptides: A comprehensive review of their sources, properties, and techno-functional challenges

The scourge of obesity arising from obesogens and poor dieting still ravages our planet as half of the global population may be overweight and obese by 2035. This metabolic disorder is intertwined with type 2 diabetes (T2D), both of which warrant alternative therapeutic options other than clinically approved drugs like orlistat with their tendency of abuse and side effects. In this review, we comprehensively describe the global obesity problem and its connection to T2D. Obesity, overconsumption of fats, the mechanism of fat digestion, obesogenic gut microbiota, inhibition of fat digestion, and natural anti-obesity compounds are discussed. Similar discussions are made for diabetes with regard to glucose regulation, the diabetic gut microbiota, and insulinotropic compounds. The sources and production of anti-obesity bioactive peptides (AOBPs) and anti-diabetic bioactive peptides (ADBPs) are also described while explaining their structure-function relationships, gastrointestinal behaviors, and action mechanisms. Finally, the techno-functional applications of AOBPs and ADBPs are highlighted.

Recent advances in medicinal and edible homologous plant polysaccharides: Preparation, structure and prevention and treatment of diabetes

Medicinal and edible homologs (MEHs) can be used in medicine and food. The National Health Commission announced that a total of 103 kinds of medicinal and edible homologous plants (MEHPs) would be available by were available in 2023. Diabetes mellitus (DM) has become the third most common chronic metabolic disease that seriously threatens human health worldwide. Polysaccharides, the main component isolated from MEHPs, have significant antidiabetic effects with few side effects. Based on a literature search, this paper summarizes the preparation methods, structural characterization, and antidiabetic functions and mechanisms of MEHPs polysaccharides (MEHPPs). Specifically, MEHPPs mainly regulate PI3K/Akt, AMPK, cAMP/PKA, Nrf2/Keap1, NF-κB, MAPK and other signaling pathways to promote insulin secretion and release, improve glycolipid metabolism, inhibit the inflammatory response, decrease oxidative stress and regulate intestinal flora. Among them, 16 kinds of MEHPPs were found to have obvious anti-diabetic effects. This article reviews the prevention and treatment of diabetes and its complications by MEHPPs and provides a basis for the development of safe and effective MEHPP-derived health products and new drugs to prevent and treat diabetes.

A review on ethnopharmacology, phytochemistry, pharmacology and potential uses of Portulaca oleracea L

ETHNOPHARMACOLOGICAL RELEVANCE

Portulaca oleracea L. (PO), popularly known as purslane, has been documented in ethnopharmacology in various countries and regions. Traditional application records indicated that PO might be used extensively to treat the common cold, dysentery, urinary tract infections, coughing, eye infections, skin problems, gynecological diseases, and pediatric illnesses.

AIM OF THE REVIEW

This paper includes a systematic review of the traditional usage, phytochemicals, pharmacological activity, and potential uses of PO to provide an overview of the research for further exploitation of PO resources.

MATERIALS AND METHODS

This article uses "Portulaca oleracea L." and "purslane" as the keywords and collects relevant information on PO from different databases, including PubMed, Web of Science, Springer, Science Direct, ACS, Wiley, CNKI, Baidu Scholar, Google Scholar, and ancient meteria medica.

RESULTS

PO is a member of the Portulacaceae family and is grown worldwide. Traditional Chinese medicine believes that purslane has the effect of improving eyesight, eliminating evil qi, quenching thirst, purgation, diuresis, hemostasis, regulating qi, promoting hair growth, detoxifying, and avoiding epidemic qi. Recent phytochemical investigations have shown that PO is a rich source of flavonoids, homoisoflavonoids, alkaloids, organic acids, esters, lignans, terpenoids, catecholamines, sterols, and cerebrosides. The purslane extracts or compounds have exhibited numerous biological activities such as anti-inflammatory, immunomodulatory, antimicrobial, antiviral, antioxidant, anticancer, renoprotective, hepatoprotective, gastroprotective, metabolic, muscle relaxant, anti-asthmatic and anti-osteoporosis properties. The significant omega-3 fatty acids, vital amino acids, minerals, and vitamins found in purslane also provide nutritional benefits. Purslane as a food/feed additive in the food industry and animal husbandry has caused concern. Its global wide distribution and tolerance to abiotic stress characteristics make it in the future sustainable development of agriculture a certain position.

CONCLUSIONS

Based on traditional usage, phytochemicals, and pharmacological activity, PO is a potential medicinal and edible plant with diverse pharmacological effects. Due to purslane's various advantages, it may have vast application potential in the food and pharmaceutical industries and animal husbandry.

Extraction, Purification, Structural Characteristics, Biological Activity and Application of Polysaccharides from Portulaca oleracea L. (Purslane): A Review

Portulaca oleracea L. (purslane) is a widely distributed plant with a long history of cultivation and consumption. Notably, polysaccharides obtained from purslane exhibit surprising and satisfactory biological activities, which explain the various benefits of purslane on human health, including anti-inflammatory, antidiabetic, antitumor, antifatigue, antiviral and immunomodulatory effects. This article systematically reviews the extraction and purification methods, chemical structure, chemical modification, biological activity and other aspects of polysaccharides from purslane collected in the Chinese Pharmacopoeia, Flora of China, Web of Science, PubMed, Baidu Scholar, Google Scholar and CNKI databases in the last 14 years, using the keywords "Portulaca oleracea L. polysaccharides" and "purslane polysaccharides". The application of purslane polysaccharides in different fields is also summarized, and its application prospects are also discussed. This paper provides an updated and deeper understanding of purslane polysaccharides, which will provide useful guidance for the further optimization of polysaccharide structures and the development of purslane polysaccharides as a novel functional material, as well as a theoretical basis for its further research and application in human health and manufacturing development.

BuOH fraction of Salix Babylonica L. extract increases pancreatic beta-cell tumor death at lower doses without harming their function

Salix babylonica L. is a species of the willow tree. Insulinoma is a tumor originating from pancreatic beta cells. This study aims to research the effect of different fractions of Salix babylonica L. leaf extract on INS-1 cells for treating pancreatic tumors. Cell death occurred at lower doses in the EtOAc fraction. The cells are functional in the BuOH fraction but not in EtOAc and H₂O fractions. The EtOAc fraction has a higher percentage of necrosis and ROS. INS1, INS2, and AKT gene expressions in the H₂O fraction, GLUT2, IR, HSP70 gene expressions, and WNT4 protein levels increased in the BuOH fraction. HSP90 gene expression, Beta-actin, GAPDH, insulin, HSP70, HSP90, HSF1, Beta-Catenin, and WNT7A protein levels were decreased, while IR immunolabelling intensity increased in both fractions. Ca⁺², K⁺, Na⁺, and CA-19-9 in the cell, Ca⁺² and K⁺ in secretion increased. The secondary metabolites in the EtOAc fraction cause more damage in INS-1 cells. Since the water fraction also causes the cells to die in high doses, cell function is damaged. The secondary metabolites in the BuOH fraction kill INS-1 cells with less damage. This makes the BuOH fraction of Salix babylonica L. more valuable.

Structure and Function of Sodium Channel Nav1.3 in Neurological Disorders

Nav1.3, encoded by the SCN3A gene, is a voltage-gated sodium channel on the cell membrane. It is expressed abundantly in the fetal brain but little in the normal adult brain. It is involved in the generation and conduction of action potentials in excitable cells. Nav1.3 plays an important role in many neurological diseases. The aim of this review is to summarize new findings about Nav1.3 in the field of neurology. Many mutations of SCN3A can lead to neuronal hyperexcitability and then cause epilepsy. The rapid recovery from inactivation and slow closed-state inactivation kinetics of Nav1.3 leads to a reduced activation threshold of the channel and a high frequency of firing of neurons. Hyperactivity of Nav1.3 also induces increased excitability of sensory neurons, a lower nociceptive threshold, and neuropathic pain. This review summarizes the structure and the function of Nav1.3 and focuses on its relationship with epilepsy and neuropathic pain.

Portulaca oleracea polysaccharides reduce serum lipid levels in aging rats by modulating intestinal microbiota and metabolites

Metabolic diseases characterized by dyslipidemia are common health problems for elderly populations. Dietary fiber intake is inversely associated with the risk of dyslipidemia. This study investigated the effects of Portulaca oleracea polysaccharide (POP) on the intestinal microbiota and its metabolites in aging rats using 16S rRNA sequencing and metabolomics techniques. Our results showed that POPs reduced the ratio of Firmicutes/Bacteroidetes (F/B), relative abundance of Fusobacteria, and levels of triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), alanine aminotransferase (ALT), and gamma-glutamyl transferase (γ-GT) in the serum of aging rats. POP supplementation also reduced 5beta-cholestane-3alpha,7alpha,12alpha,25-tetrol, and vaccenic acid concentrations in lipids and lipoid-like molecules, while soyasapogenol E and monoacylglycerol (MG) (24:0/0:0/0:0) levels increased. This study demonstrated that POP’s beneficial effects on lipid levels in aging rats might be partially attributable to the modification of gut microbiota and related metabolites.

ATP Secretion and Metabolism in Regulating Pancreatic Beta Cell Functions and Hepatic Glycolipid Metabolism

Diabetes (DM), especially type 2 diabetes (T2DM) has become one of the major diseases severely threatening public health worldwide. Islet beta cell dysfunctions and peripheral insulin resistance including liver and muscle metabolic disorder play decisive roles in the pathogenesis of T2DM. Particularly, increased hepatic gluconeogenesis due to insulin deficiency or resistance is the central event in the development of fasting hyperglycemia. To maintain or restore the functions of islet beta cells and suppress hepatic gluconeogenesis is crucial for delaying or even stopping the progression of T2DM and diabetic complications. As the key energy outcome of mitochondrial oxidative phosphorylation, adenosine triphosphate (ATP) plays vital roles in the process of almost all the biological activities including metabolic regulation. Cellular adenosine triphosphate participates intracellular energy transfer in all forms of life. Recently, it had also been revealed that ATP can be released by islet beta cells and hepatocytes, and the released ATP and its degraded products including ADP, AMP and adenosine act as important signaling molecules to regulate islet beta cell functions and hepatic glycolipid metabolism via the activation of P2 receptors (ATP receptors). In this review, the latest findings regarding the roles and mechanisms of intracellular and extracellular ATP in regulating islet functions and hepatic glycolipid metabolism would be briefly summarized and discussed.

A review on bioactive phytochemicals and ethnopharmacological potential of purslane (Portulaca oleracea L.)

The Portulaca oleracea L. commonly known as purslane is distributed all over the world and easily grows in diverse soil and climatic conditions. It has been traditionally used as a nutritious and ethnomedicinal food across the globe. Various studies have shown that the plant is a rich source of various important phytochemicals such as flavonoids, alkaloids, terpenoids, proteins, carbohydrates, and vitamins such as A, C, E, and B, carotenoids and minerals such as phosphorus, calcium, magnesium and zinc. It is particularly very important because of the presence of a very high concentration of omega-3- fatty acids especially α-linolenic acid, gamma-linolenic acid and linoleic acid, which are not generally synthesized in terrestrial plants. Various parts of purslane are known for ethnomedicinal and pharmacological uses because of its anti-inflammatory, antidiabetic, skeletal muscle relaxant, antitumor, hepatoprotective, anticancer, antioxidant, anti-insomnia, analgesic, gastroprotective, neuroprotective, wound healing and antiseptic activities. Due to multiple benefits of purslane, it has become an important wonder crop and various scientists across the globe have shown much interest in it as a healthy food for the future. In this review, we provide an update on the phytochemical and nutritional composition of purslane, its usage as nutritional and an ethnomedicinal plant across the world. We further provide a detailed account on ethnopharmacological studies that have proved the ethnomedicinal properties of purslane.

Therapeutic Screening of Herbal Remedies for the Management of Diabetes

The study of diabetes mellitus (DM) patterns illustrates increasingly important facts. Most importantly, they include oxidative stress, inflammation, and cellular death. Up to now, there is a shortage of drug therapies for DM, and the discovery and the development of novel therapeutics for this disease are crucial. Medicinal plants are being used more and more as an alternative and natural cure for the disease. Consequently, the objective of this review was to examine the latest results on the effectiveness and protection of natural plants in the management of DM as adjuvant drugs for diabetes and its complex concomitant diseases.

Effect of Portulaca Oleracea (purslane) extract on liver enzymes, lipid profile, and glycemic status in nonalcoholic fatty liver disease: A randomized, double-blind clinical trial

Purslane (Portulaca oleracea L.) is the richest green leafy vegetable source of omega-3, especially alpha linolenic acid (ALA). Experimental studies have shown beneficial effects of purslane extract on liver enzymes. The aim of the present study was to examine the effect of purslane hydroalcohoic extract in patients with non-alcoholic fatty liver disease (NAFLD). In a randomized double-blinded clinical trial, 74 patients were randomly assigned to receive either 300 mg purslane extract or placebo capsules for 12 weeks. Compared with baseline, alanine aminotransferase (ALT) (-9 [-17, 0.50] mg/dl; p = .007), aspartate aminotransferase (AST) (-4 [-10, -0.50] mg/dl; p = .001), gamma glutamyltransferase (GGT) (-6.21 ± 9.85 mg/dL; p < .001), fasting blood glucose (FBG) (-8 [-11, -1.50] mg/dl; p < .001) insulin resistance (-0.95 ± 2.23; p = .020), triglyceride (-20 [-67.50, 3.50] mg/dl; p = .010), and low-density lipoprotein cholesterol (LDL-C) (-5 [-12, -1] mg/dl; p < .001) decreased significantly in the purslane group. At the end of study, no significant changes were observed in liver steatosis grade, insulin, liver enzymes, total bilirubin, lipid profile, and blood pressure between the two groups. The findings of our study show that purslane extract at the dose of 300 mg/day for 12 weeks has no significant effects on liver enzymes, lipid profile, and glycemic indices in patients with NAFLD.

Effects of Polyphenols on Insulin Resistance

Insulin resistance (IR) is apparent when tissues responsible for clearing glucose from the blood, such as adipose and muscle, do not respond properly to appropriate signals. IR is estimated based on fasting blood glucose and insulin, but some measures also incorporate an oral glucose challenge. Certain (poly)phenols, as supplements or in foods, can improve insulin resistance by several mechanisms including lowering postprandial glucose, modulating glucose transport, affecting insulin signalling pathways, and by protecting against damage to insulin-secreting pancreatic β-cells. As shown by intervention studies on volunteers, the most promising candidates for improving insulin resistance are (-)-epicatechin, (-)-epicatechin-containing foods and anthocyanins. It is possible that quercetin and phenolic acids may also be active, but data from intervention studies are mixed. Longer term and especially dose-response studies on mildly insulin resistant participants are required to establish the extent to which (poly)phenols and (poly)phenol-rich foods may improve insulin resistance in compromised groups.

Anti-diabetic and anti-parasitic properties of a family of luminescent zinc coordination compounds based on the 7-amino-5-methyl-1,2,4-triazolo[1,5-a]pyrimidine ligand

We report on the formation of a triazolopyrimidine derivative ligand, 7-amino-5-methyl-1,2,4-triazolo[1,5-a]pyrimidine (7-amtp), and a new family of coordination compounds based on this ligand and zinc as metal ion, synthesized by conventional routes. These materials possess different mononuclear structures, namely [ZnCl₂(7-amtp)₂] (1), [Zn(7-amtp)₂(H₂O)₄](NO₃)₂·2(7-amtp)·6H₂O (2) and [Zn(7-amtp)₂(H₂O)₄](SO₄)·1.5H₂O (3) derived from the use of different zinc (II) salts, in such a way that the counterions govern the crystallization to a large extent. These compounds present and show variable luminescent properties based on ligand-centred charge transfers which have been deeply studied by Time Dependent Density Functional Theory (TD-DFT) calculations. When these compounds are transferred to solution, preserving complex entities as corroborated by NMR studies, they present interesting anti-diabetic and anti-parasitic capabilities, with a comparatively higher selectivity index than other previously reported triazolopyrimidine-based materials. The results derived from in vivo experiments conducted in mice also confirm their promising activity as anti-diabetic drug being capable of dropping glucose levels after oral administration. Therefore, these new materials may be considered as excellent candidates to be further investigated in the field of luminescent coordination compounds with biomedical applications.

Remedying the Mitochondria to Cure Human Diseases by Natural Products

Mitochondria are the ‘engine' of cells. Mitochondrial dysfunction is an important mechanism in many human diseases. Many natural products could remedy the mitochondria to alleviate mitochondria-involved diseases. In this review, we summarized the current knowledge of the relationship between the mitochondria and human diseases and the regulation of natural products to the mitochondria. We proposed that the development of mitochondrial regulators/nutrients from natural products to remedy mitochondrial dysfunction represents an attractive strategy for a mitochondria-involved disorder therapy. Moreover, investigating the mitochondrial regulation of natural products can potentiate the in-depth comprehension of the mechanism of action of natural products.

Macro- and Micronutrients from Traditional Food Plants Could Improve Nutrition and Reduce Non-Communicable Diseases of Islanders on Atolls in the South Pacific

Pacific Islanders have paid dearly for abandoning traditional diets, with diabetes and other non-communicable diseases (NCD) widespread. Starchy root crops like sweet potato, taro, and cassava are difficult to grow on the potassium-deficient soils of atolls, and high energy, low nutrient imported foods and drinks are popular. Nutritious, leafy food plants adapted to alkaline, salty, coral soils could form part of a food system strategy to reduce NCD rates. This project targeted four atolls south of Tarawa, Kiribati, and was later extended to Tuvalu. Mineral levels in diverse, local leafy food plants were compared to reveal genotype–environment interactions. Food plants varied in ability to accumulate minerals in leaves and in tolerance of mineral-deficient soils. Awareness activities which included agriculture, health, and education officers targeted atoll communities. Agriculture staff grew planting material in nurseries and provided it to farmers. Rejuvenation of abandoned giant swamp taro pits to form diversified nutritious food gardens was encouraged. Factsheets promoted the most suitable species from 24 analyzed, with multiple samples of each. These included Cnidoscolus aconitifolius (chaya), Pseuderanthemum whartonianum (ofenga), Polyscias scutellaria (hedge panax), and Portulaca oleracea (purslane). The promoted plants have been shown in other studies to have anti-NCD effects. Inclusion of the findings in school curricula and practical application in the form of demonstration school food gardens, as well as increased uptake by farmers, are needed. Further research is needed on bioavailability of minerals in plants containing phytates and tannins.

Polysaccharides from Opuntia milpa alta alleviate alloxan-induced INS-1 cells apoptosis via reducing oxidative stress and upregulating Nrf2 expression

The incidence and progression of type 2 diabetes are closely related to pancreatic β-cell damage. Oxidative stress may be one of the key factors contributing to β-cell apoptosis. Opuntia milpa alta polysaccharides (MAPs) are water-soluble macromolecular polysaccharides that have antidiabetic effects in vivo. Therefore, we hypothesized that MAPs might effectively prevent β-cell apoptosis via the inhibition of oxidative damages. In this study, INS-1 cells were exposed to alloxan with different concentrations of MAPs in vitro, and the cell viability, oxidative enzyme activities, nitric oxide production, reactive oxygen species production, apoptosis, and the expression of proteins in the antioxidant nucleus transcription factor NF-E2-related factor 2 (Nrf2) pathway and proteins related to apoptosis were measured to assess oxidative stress responses and apoptosis. The results indicated that INS-1 cell viabilities and superoxide dismutase and reduced glutathione activities were significantly restored, whereas lactate dehydrogenase releases and reactive oxygen species, nitric oxide, and malondialdehyde levels were greatly decreased after MAPs treatment. We found that MAPs could attenuate alloxan-induced apoptosis by increasing the expression of Bcl-2 and decreasing the expression of Bax and the activities of caspase-3 and caspase-9. The results of Western blot revealed that MAPs suppressed the expression of cleaved caspase-3 and cleaved PARP and upregulated the expression of nucleus Nrf2 and its downstream protein. These findings indicated that MAPs could alleviate alloxan-induced β-cell apoptosis by reducing oxidative stress and upregulating Nrf2 expression.