Phenolic compounds ameliorate the glucose uptake in HepG2 cells' insulin resistance via activating AMPK

Bioprospection of rattlesnake venom peptide fractions with anti-adipose and anti-insulin resistance activity in vitro

Animal venoms are natural products that have served as a source of novel molecules that have inspired novel drugs for several diseases, including for metabolic diseases such as type-2 diabetes and obesity. From venoms, toxins such as exendin-4 (Heloderma suspectum) and crotamine (Crotalus durissus terrificus) have demonstrated their potential as treatments for obesity. Moreover, other toxins such as Phospholipases A2 and Disintegrins have shown their potential to modulate insulin secretion in vitro. This suggests an unexplored diversity of venom peptides with a potential anti-obesogenic in Mexican rattlesnake venoms. For that reason, this study explored the in vitro effect of Crotalus venom peptide-rich fractions on models for insulin resistance, adipocyte lipid accumulation, antioxidant activity, and inflammation process through nitric oxide production inhibition. Our results demonstrated that the peptide-rich fractions of C. aquilus, C. ravus, and C. scutulatus scutulatus were capable of reverting insulin resistance, enhancing glucose consumption to normal control; C. culminatus, C. molossus oaxacus, and C. polystictus diminished the lipid accumulation on adipocytes by 20%; C. aquilus, C. ravus, and C. s. salvini had the most significant cellular antioxidant activity, having nearly 80% of ROS inhibition. C. aquilus, C. pyrrhus, and C. s. salvini inhibited nitric oxide production by about 85%. We demonstrated the potential of these peptides from Crotalus venoms to develop novel drugs to treat type-2 diabetes and obesity. Moreover, we described for the first time that Crotalus venom peptide fractions have antioxidant and inflammatory properties in vitro models.

Coffee Bioactive N-Methylpyridinium: Unveiling Its Antilipogenic Effects by Targeting De Novo Lipogenesis in Human Hepatocytes

SCOPE

Type 2 diabetes and nonalcoholic fatty liver diseases (NAFLDs) are promoted by insulin resistance (IR), which alters lipid homeostasis in the liver. This study aims to investigate the effect of N-methylpyridinium (NMP), a bioactive alkaloid of coffee brew, on lipid metabolism in hepatocytes.

METHODS AND RESULTS

The effect of NMP in modulating lipid metabolism is evaluated at physiological concentrations in a diabetes cell model represented by HepG2 cells cultured in a high-glucose medium. Hyperglycemia triggers lipid droplet accumulation in cells and enhances the lipogenic gene expression, which is transactivated by sterol regulatory element binding protein-1 (SREBP-1). Lipid droplet accumulation alters the redox status and endoplasmic reticulum (ER) stress, leading to the activation of the unfolded protein response and antioxidative pathways by X-Box Binding Protein 1(XBP-1)/eukaryotic Initiation Factor 2 alpha (eIF2α) Protein Kinase RNA-Like ER Kinase and nuclear factor erythroid 2-related factor 2 (NRF2), respectively. NMP induces the phosphorylation of AMP-dependent protein kinase (AMPK) and acetyl-CoA carboxylase α (ACACA), and improves the redox status and ER homeostasis, essential steps to reduce lipogenesis and lipid droplet accumulation.

CONCLUSION

These results suggest that NMP may be beneficial for the management of T2D and NAFLD by ameliorating the cell oxidative and ER homeostasis and lipid metabolism.

Effects of Purified Vitexin and Iso-Vitexin from Mung Bean Seed Coat on Antihyperglycemic Activity and Gut Microbiota in Overweight Individuals' Modulation

Exceeding a healthy weight significantly elevates the likelihood of developing type 2 diabetes (T2DM). A commercially available singular constituent, available as either purified vitexin or iso-vitexin, has been associated with a decreased risk of T2DM, but its synergistic effect has not been reported yet. Vitexin and iso-vitexin were extracted using an ethanol-based solvent from mung bean seed coat (MBCE) and subsequently purified using preparative liquid chromatography (Prep-LC). Eleven mixture ratios of vitexin and/or iso-vitexin were determined for their antioxidant and antihyperglycemic activities. The 1:1.5 ratio of vitexin to iso-vitexin from MBCE demonstrated the most synergistic effects for enzyme inhibition and glucose uptake in HepG2 cells within an insulin-resistant system, while these ratios exhibited a significantly lower antioxidant capacity than that of each individual component. In a gut model system, the ratio of 1:1.5 (vitexin and iso-vitexin) regulated the gut microbiota composition in overweight individuals by decreasing the growth of Enterobacteriaceae and Enterococcaceae, while increasing in Ruminococcaceae and Lachnospiraceae. The application of vitexin/iso-vitexin for 24 h fermentation enhanced a high variety of abundances of 21 genera resulting in five genera of Parabacteroides, Ruminococcus, Roseburia, Enterocloster, and Peptacetobacter, which belonged to the phylum Firmicutes, exhibiting high abundant changes of more than 5%. Only two genera of Proteus and Butyricicoccus belonging to Proteobacteria and Firmicutes decreased. The findings suggest that these phytochemicals interactions could have synergistic effects in regulating glycemia, through changes in antihyperglycemic activity and in the gut microbiota in overweight individuals. This optimal ratio can be utilized by industries to formulate more potent functional ingredients for functional foods and to create nutraceutical supplements aimed at reducing the risk of T2DM in overweight individuals.

Dietary (poly)phenols as modulators of the biophysical properties in endothelial cell membranes: its impact on nitric oxide bioavailability in hypertension

Hypertension is a major contributor to premature death, owing to the associated increased risk of damage to the heart, brain and kidneys. Although hypertension is manageable by medication and lifestyle changes, the risk increases with age. In an increasingly aged society, the incidence of hypertension is escalating, and is expected to increase the prevalence of (cerebro)vascular events and their associated mortality. Adherence to plant-based diets improves blood pressure and vascular markers in individuals with hypertension. Food flavonoids have an inhibitory effect towards angiotensin-converting enzyme (ACE1) and although this effect is greatly diminished upon metabolization, their microbial metabolites have been found to improve endothelial nitric oxide synthase (eNOS) activity. Considering the transmembrane location of ACE1 and eNOS, the ability of (poly)phenols to interact with membrane lipids modulate the cell membrane's biophysical properties and impact on nitric oxide (·NO) synthesis and bioavailability, remain poorly studied. Herein, we provide an overview of the current knowledge on the lipid remodeling of endothelial membranes with age, its impact on the cell membrane's biophysical properties and ·NO permeability across the endothelial barrier. We also discuss the potential of (poly)phenols and other plant-based compounds as key players in hypertension management, and address the caveats and challenges in adopted methodologies.

A comprehensive review of apigenin a dietary flavonoid: biological sources, nutraceutical prospects, chemistry and pharmacological insights and health benefits

A multitude of plant-derived bioactive compounds have shown significant promise in preventing chronic illnesses, with flavonoids constituting a substantial class of naturally occurring polyphenolic compounds. Apigenin, a flavone identified as 4',5,7-trihydroxyflavone, holds immense promise as a preventative agent against chronic illnesses. Despite its extensive research and recognized nutraceutical value, its therapeutic application remains underexplored, necessitating further clinical investigations. This review delves into the biological sources, nutraceutical prospects, chemistry, pharmacological insights, and health benefits of apigenin. Through multifaceted analytical studies, we explore its diverse pharmacological profile and potential therapeutic applications across various health domains. The manuscript comprehensively examines apigenin's role as a neuroprotective , anti-inflammatory compound, and a potent antioxidant agent. Additionally, its efficacy in combating cardiovascular diseases, anti-diabetic properties, and anticancer potential has been discussed. Furthermore, the antimicrobial attributes and the challenges surrounding its bioavailability, particularly from herbal supplements have been addressed. Available in diverse forms including tablets, capsules, solid dispersions, co-crystals, inclusion complexes and nano formulations. Additionally, it is prevalent as a nutraceutical supplement in herbal formulations. While strides have been made in overcoming pharmacokinetic hurdles, further research into apigenin's clinical effectiveness and bioavailability from herbal supplements remains imperative for its widespread utilization in preventive medicine.

Genistein and metformin regulate glycerol kinase and the enzymes of glycerol 3-phosphate shuttle in a differential manner in myocytes, hepatocytes and adipocytes

Glycerol kinase (GK) and glycerol 3-phosphate dehydrogenase (GPDH) are critical in glucose homeostasis. The role of genistein and metformin on these enzymes and glucose production was investigated in C2C12, HepG2, and 3T3-L1 cells. Enzyme kinetics, Real-Time PCR and western blots were performed to determine enzyme activities and expressions of mRNAs and proteins. Glucose production and uptake were also measured in these cells. siRNAs were used to assess their impact on the enzymes and glucose production. Ki values for the compounds were determined using purified GK and GPDH. Genistein decreased GK activity by ∼45 %, while metformin reduced cGPDH and mGPDH activities by ∼32 % and ∼43 %, respectively. Insignificant changes in expressions (mRNAs and proteins) of the enzymes were observed. The compounds showed dose-dependent alterations in glucose production and uptake in these cells. Genistein non-competitively inhibited His-GK activity (Ki 19.12 μM), while metformin non-competitively inhibited His-cGPDH (Ki 75.52 μM) and mGPDH (Ki 54.70 μM) activities. siRNAs transfection showed ∼50 % and ∼35 % decrease in activities of GK and mGPDH and a decrease in glucose production (0.38-fold and 0.42-fold) in 3T3-L1 cells. Considering the differential effects of the compounds, this study may provide insights into the potential therapeutic strategies for type II diabetes mellitus.

N-p-coumaroyloctopamine ameliorates hepatic glucose metabolism and oxidative stress involved in a PI3K/AKT/GSK3β pathway

Type 2 diabetes mellitus is regarded as a chronic metabolic disease characterized by hyperglycemia. Long-term hyperglycemia may result in oxidative stress, damage pancreatic β-cell function and induce insulin resistance. Herein we explored the anti-hypoglycemic effects and mechanisms of action of N-p-coumaroyloctopamine (N-p-CO) in vitro and in vivo. N-p-CO exhibited high antioxidant activity, as indicated by the increased activity of SOD, GSH and GSH-Px in HL-7702 cells induced by both high glucose (HG) and palmitic acid (PA). N-p-CO treatment significantly augmented glucose uptake and glycogen synthesis in HG/PA-treated HL-7702 cells. Moreover, administration of N-p-CO in diabetic mice induced by both high-fat diet (HFD) and streptozotocin (STZ) not only significantly increased the antioxidant levels of GSH-PX, SOD and GSH, but also dramatically alleviated hyperglycemia and hepatic glucose metabolism in a dose-dependent manner. More importantly, N-p-CO upregulated the expressions of PI3K, AKT and GSK3β proteins in both HG/PA-induced HL-7702 cells and HFD/STZ-induced mice. These findings clearly suggest that N-p-CO exerts anti-hypoglycemic and anti-oxidant effects, most probably via the regulation of a PI3K/AKT/GSK3β signaling pathway. Thus, N-p-CO may have high potentials as a new candidate for the prevention and treatment of diabetes.

Berberine ameliorates glucocorticoid-induced hyperglycemia: an in vitro and in vivo study

Berberine (BBR), a bioactive compound isolated from Coptidis Rhizoma, possesses diverse pharmacological activities including anti-bacterial, anti-inflammatory, antitumor, hypolipidemic, and anti-diabetic. However, its role as an anti-diabetic agent in animal models of dexamethasone (Dex)-induced diabetes remains unknown. Studies have shown that natural compounds including aloe, caper, cinnamon, cocoa, green and black tea, and turmeric can be used for treating Type 2 diabetes mellitus (DM). Compared to conventional drugs, natural compounds have less side effects and are easily available. Herein, we studied the anti-diabetic effects of BBR in a mice model of Dex-induced diabetes. HepG2 cell line was used for glucose release and glycogen synthesis studies. Cell proliferation was measured by methylthiotetrazole (MTT) assay. For animal studies, mice were treated with Dex (2 mg/kg, i.m.) for 30 days and effect of BBR at the doses 100, 200, and 500 mg/kg (p.o.) was analyzed. Glucose, insulin, and pyruvate tests were performed for evaluating the development of the diabetic model. Echo MRI was performed to assess the fat mass. Further, to elucidate the mechanism of action of BBR, mRNA expression of genes regulating gluconeogenesis, glucose uptake, and glycolysis was analyzed. In vitro BBR had no impact on cell viability up to a concentration of 50 μM. Moreover, BBR suppressed the hepatic glucose release and improved glucose tolerance in HepG2 cells. In vivo, BBR improved glucose homeostasis in diabetic mice as evidenced by enhanced glucose clearance, increased glycolysis, elevated glucose uptake, and decreased gluconeogenesis. Further, Dex treatment increased the total fat mass in mice, which was ameliorated by BBR treatment. BBR improves glucose tolerance by increasing glucose clearance, inhibiting hepatic glucose release, and decreasing obesity. Thus, BBR may become a potential therapeutic agent for treating glucocorticoid-induced diabetes and obesity in the future.

Research-based Analytical Procedures to Evaluate Diabetic Biomarkers and Related Parameters: In Vitro and In Vivo Methods

BACKGROUND

The degenerative tendency of diabetes leads to micro- and macrovascular complications due to abnormal levels of biochemicals, particularly in patients with poor diabetic control. Diabetes is supposed to be treated by reducing blood glucose levels, scavenging free radicals, and maintaining other relevant parameters close to normal ranges. In preclinical studies, numerous in vivo trials on animals as well as in vitro tests are used to assess the antidiabetic and antioxidant effects of the test substances. Since a substance that performs poorly in vitro won't perform better in vivo, the outcomes of in vitro studies can be utilized as a direct indicator of in vivo activities.

OBJECTIVE

The objective of the present study is to provide research scholars with a comprehensive overview of laboratory methods and procedures for a few selected diabetic biomarkers and related parameters.

METHOD

The search was conducted on scientific database portals such as ScienceDirect, PubMed, Google Scholar, BASE, DOAJ, etc. Conclusion: The development of new biomarkers is greatly facilitated by modern technology such as cell culture research, lipidomics study, microRNA biomarkers, machine learning techniques, and improved electron microscopies. These biomarkers do, however, have some usage restrictions. There is a critical need to find more accurate and sensitive biomarkers. With a few modifications, these biomarkers can be used with or even replace conventional markers of diabetes.

Analysis of Cell Glycogen with Quantitation and Determination of Branching Using Liquid Chromatography-Mass Spectrometry

Glycogen is a highly branched biomacromolecule that functions as a glucose buffer. It is involved in multiple diseases such as glycogen storage disorders, diabetes, and even liver cancer, where the imbalance between biosynthetic and catabolic enzymes results in structural alterations and abnormal accumulation of glycogen that can be toxic to cells. Accurate and sensitive glycogen quantification and structural determination are prerequisites for understanding the phenotypes and biological functions of glycogen under these conditions. In this research, we furthered cell glycogen characterization by presenting a highly sensitive method to measure the glycogen content and degree of branching. The method employed a novel fructose density gradient as an alternative to the traditional sucrose gradient to fractionate glycogen from cell mixtures using ultracentrifugation. Fructose was used to avoid the large glucose background, allowing the method to be highly quantitative. The glycogen content was determined by quantifying 1-phenyl-3-methyl-5-pyrazolone (PMP)-derivatized glucose residues obtained from acid-hydrolyzed glycogen using ultra-high-performance liquid chromatography/triple quadrupole mass spectrometry (UHPLC/QqQ-MS). The degree of branching was determined through linkage analysis where the glycogen underwent permethylation, hydrolysis, PMP derivatization, and UHPLC/QqQ-MS analysis. The new approach was used to study the effect of insulin on the glycogen phenotypes of human hepatocellular carcinoma (Hep G2) cells. We observed that cells produced greater amounts of glycogen with less branching under increasing insulin levels before reaching the cell's insulin-resistant state, where the trend reversed and the cells produced less but higher-branched glycogen. The advantage of this method lies in its high sensitivity in characterizing both the glycogen level and the structure of biological samples.

Elucidating the Mechanism of Agrimonolide in Treating Colon Cancer Based on Network Pharmacology

Purpose

This study reported the efficacy and underlying mechanism of agrimonolide (AM) in treating colon cancer.

Methods

Colon cancer-AM-related targets were screened from online database. AM targets for colon cancer were identified by Venn diagram. Main molecular function, biological process, cellular component and pathways associated with AM targets for colon cancer were analyzed by GO and KEGG enrichment analysis. Relationship of the 10 core targets of AM for colon cancer with the top 15 BP and KEGG pathways was analyzed by Cytoscape software. A "component-target-pathway" network was constructed to select the hub genes of AM for colon cancer. AM effects on colon cancer cell viability, proliferation, invasion, migration and apoptosis were researched by CCK-8, colony formation, Transwell invasion, wound healing and flow cytometry assays. Tumor-bearing nude mice models were constructed and given AM treatment. Hub gene expression in cells/tissues was detected by Western blot.

Results

A total of 107 targets were selected as AM targets for colon cancer. The 10 core targets were related to the top 15 biological process terms and KEGG pathways. PI3K, AKT and mTOR were selected as the hub genes of AM for colon cancer. AM weakened colon cell proliferation, invasion, migration and apoptosis inhibition, and suppressed colon cell in vivo growth. AM up-regulated Caspase-3 and BAX proteins, down-regulated C-Myc, Cyclin D1 and BCL-2 proteins, and inactivated the PI3K/AKT/mTOR pathway both in vitro and in vivo.

Conclusion

AM suppressed colon cancer progression through inactivating the PI3K/AKT/mTOR pathway. It may be useful for colon cancer treatment.

The Muscle-Conditioned Medium Containing Protocatechuic Acid Improves Insulin Resistance by Modulating Muscle Communication with Liver and Adipose Tissue

Diabetes mellitus is a public health concern, affecting 10.5% of the population. Protocatechuic acid (PCA), a polyphenol, exerts beneficial effects on insulin resistance and diabetes. This study investigated the role of PCA in improving insulin resistance and the crosstalk between muscle with liver and adipose tissue. C2C12 myotubes received four treatments: Control, PCA, insulin resistance (IR), and IR-PCA. Conditioned media from C2C12 was used to incubate HepG2 and 3T3-L1 adipocytes. The impact of PCA was analyzed on glucose uptake and signaling pathways. PCA (80 µM) significantly enhanced glucose uptake in C2C12, HepG2, and 3T3-L1 adipocytes (p < 0.05). In C2C12, PCA significantly elevated GLUT-4, IRS-1, IRS-2, PPAR-γ, P-AMPK, and P-Akt vs. Control (p ≤ 0.05), and modulated pathways in IR-PCA. In HepG2, PPAR-γ and P-Akt increased significantly in Control (CM) vs. No CM, and PCA dose upregulated PPAR-γ, P-AMPK, and P-AKT (p < 0.05). In the 3T3-L1 adipocytes, PI3K and GLUT-4 expression was elevated in PCA (CM) vs. No CM. A significant elevation of IRS-1, GLUT-4, and P-AMPK was observed in IR-PCA vs. IR (p ≤ 0.001). Herein, PCA strengthens insulin signaling by activating key proteins of that pathway and regulating glucose uptake. Further, conditioned media modulated crosstalk between muscle with liver and adipose tissue, thus regulating glucose metabolism.

The significant antidyslipidemic, hypoglycemic, antihyperglycemic, and antiobesity activities of the aqueous extracts of Agave Sisalana juice are partly mediated via modulation of calcium signaling pathways

Plant species in the genus Agave, including Agave sisalana, have found extensive application in African and Asian traditional medicine. Inspired by the use of the edible sweet sap known as Aguamiel (obtained from specific mature agave species such as Agave salmiana) in Mexico by diabetic patients to improve their diabetic condition, this study investigated the effects of Agave sisalana extracts prepared by lyophilization, fermentation, and saponin extraction from sisal juice in a rodent model of metabolic syndrome. The metabolic syndrome was induced by administering a high fat and high fructose diet to freshly weaned Sprague-Dawley rats for eight weeks. The A. sisalana extracts possessed significant hypoglycemic effects [3.883 ± 0.371 mmol/L (normal group) vs. 8.183 ± 0.5845 mmol/L (negative control) vs. 3.767 ± 0.2716 mmol/L (positive control) vs. 4.167 ± 0.4602 mmol/L (FSP) vs. 4.533 ± 0.3169 mmol/L (FerSP) vs. 3.5 ± 0.2309 mmol/L (FS LD) vs. 3.867 ± 0.3353 mmol/L (FS HD) vs. 4.617 ± 0.2725 mmol/L (FerS LD) vs. 4.383 ± 0.3114 mmol/L (FerS HD): p < 0.0001]. The extracts also possessed significant antihyperlipidemic effects with significant differences in total serum cholesterol between the groups [1.398 ± 0.1232 mmol/L (normal group) vs. 4.225 ± 0.4135 mmol/L (negative control) vs. 1.582 ± 0.154 mmol/L (positive control) vs. 1.245 ± 0.0911 mmol/L (FSP) vs. 1.393 ± 0.1423 mmol/L (FerSP) vs. 1.387 ± 0.0924 mmol/L (FS LD) vs. 1.761 ± 0.1495 mmol/L (FS HD) vs. 1.698 ± 0.1294 mmol/L (FerS LD) vs. 1.6975 ± 0.0982 mmol/L (FerS HD): p < 0.0001]. Further, significant antiobesity effects of the A.sisalana extracts were observed with significant differences in weight among the groups [196.3 ± 6.49 g (normal group) vs. 298.9 ± 6.67 g (negative control) vs. 215.3 ± 6.06 g (positive control) vs. 195.4 ± 3.92 g (FSP) vs. 213.1 ± 5.21 g (FerSP) vs. 190.8 ± 6.49 g (FS LD) vs. 198.9 ± 4.31 g (FS HD) vs. 204.7 ± 4.78 g (FerS LD) vs. 208.7 ± 6.21 g (FerS HD): p < 0.0001]. Network pharmacology studies indicated that the chemical components found in sisal juice primarily exert their effects by modulating the voltage-gated calcium channels CACNA1S, CACNA1D, and CACNA1C, in the beta cells of the islets of Langerhans.

Polymeric micelles loaded with glyburide and vanillic acid: I. Formulation development, in-vitro characterization and bioavailability studies

The co-formulation of glyburide (Gly) and vanillic acid (VA) as such in the form of nanomedicine has never been explored to treat metabolic diseases including type 2 diabetes mellitus. Both the drugs possess dissolution rate-limited oral bioavailability leading to poor therapeutic efficacy. Hence, co-loading these drugs into a nanocarrier could overcome their poor oral bioavailability related challenges. Owing to this objective, both drugs were co-loaded in amphiphilic polymeric micelles (APMs) and evaluated for their biopharmaceutical outcomes. The APMs were prepared using mPEG-b-PCL/CTAB as a copolymer-surfactant system via the liquid antisolvent precipitation (LAP) method. The design of these APMs were optimized using Box Behnken Design by taking various process/formulation based variables to achieve the desired micellar traits. The release of both the drugs from the optimized co-loaded APMs was compared in different media and displayed a remarkable sustained release profile owing to their hydrophobic interactions with the PCL core. The in vitro cytotoxicity study of co-loaded APMs on Caco-2 cells revealed 70 % cell viability in a concentration-dependent manner. The preventive effects of Gly and VA co-loaded in APMs on glucose uptake was studied in insulin-responsive human HepG2 cells treated with high glucose. The co-loading of both the drugs in optimized APMs exhibited synergistic glucose-lowering activity (p < 0.001) than raw drugs with low cytotoxicity on HepG2 cells within the test concentration. This could be attributed to an increase in the relative oral bioavailability of both the drugs in APMs i.e., 868 % for Gly and 87 % for VA respectively.

Agrimonolide inhibits cancer progression and induces ferroptosis and apoptosis by targeting SCD1 in ovarian cancer cells

BACKGROUND

Ovarian cancer is a gynaecological tumour has high incidence and mortality rates. Agrimonolide, isolated from Agrimonia pilosa Ledeb, has multiple biomedical activities, including anticancer activity.

PURPOSE

Here, we aimed to reveal the function of agrimonolide on ovarian cancer progression.

METHODS

MTT assay, colony-formation assay, flow cytometry, transwell assay, scratch test, western immunoblotting, reactive oxygen species (ROS) detection, and ferroptosis analysis were performed to reveal the role and underlying mechanisms of agrimonolide in ovarian cancer cell lines (A2780 and SKOV-3). The effects of agrimonolide on the SKOV-3 xenograft model were also studied.

RESULTS

Agrimonolide dose-dependently inhibited proliferation, migration, and invasion and promoted apoptosis in A2780 and SKOV-3 cells. Agrimonolide induced ferroptosis in tumour cells, evidenced by the increased levels of ROS, total iron, and Fe²⁺ and downregulation of ferroptosis indicators (SLC7A11 and GPX4). The SwissTargetPrediction and Comparative Toxicogenomics Database predicted SCD1 as a target protein for agrimonolide. Molecular Operating Environment software docked agrimonolide in the SCD1 protein, and the binding energy of interaction was -8.21 kcal/mol. The effects of agrimonolide on proliferation, invasion, and induction of apoptosis and ferroptosis were attenuated by SCD1 overexpression in A2780 and SKOV-3 cells. Additionally, agrimonolide attenuated the tumour growth of ovarian cancer in the SKOV-3 xenograft model and significantly downregulated SCD1 in tumour tissues.

CONCLUSION

Our study is the first to suggest that agrimonolide acts as a novel apoptosis- and ferroptosis-inducing agent in ovarian cancer cells by targeting SCD1. Agrimonolide may be a novel therapeutic agent for treating ovarian cancer.

Gut Microbiota Modulation, Anti-Diabetic and Anti-Inflammatory Properties of Polyphenol Extract from Mung Bean Seed Coat (Vigna radiata L.)

The present study investigated the gut health, anti-diabetic, and anti-inflammatory activities of mung bean seed coat extract (MSE). MSE was obtained by pressurized liquid extraction (PLE) using 50% ethanol as the extracting solvent. After 24 h of in vitro human fecal fermentation, MSE exhibited higher productions of total short-chain fatty acids (SCFA) than those of the control group (CON) and other polyphenol-rich substrates, including gallic acid (GA) and vitexin (VIT) (p > 0.05), but still lower than the fructo-oligosaccharide (FOS). In 16S-rRNA next-generation sequencing, MSE regulated the composition of gut microbiota by stimulating the growth of the beneficial bacteria Enterococcus, Ruminococcus, Blautia, and Bacteroides and decreasing the growth of the potential pathogenic bacteria Escherichia-Shigella. Similarly, qPCR showed increased numbers of Bifidobacterium, Lactobacillus, Faecalibacterium prausnitzii, and Prevotella, compared with those of CON (p < 0.05). MSE also reduced reactive oxygen species and increased glucose uptake in insulin-resistant HepG2 cells dose-dependently. The anti-inflammatory activity of MSE was observed in LPS-stimulated THP-1 monocytes with the reduction of TNFα, IL-1β, IL-6, and IL-8 genes. The data demonstrated the potential applications of MSE as a dietary supplement with gut health benefits and its ability to mitigate diabetes and inflammatory-related diseases.

The Antioxidant and Hypolipidemic Effects of Mesona Chinensis Benth Extracts

In this study, the antioxidant and hypolipidemic effects of Mesona Chinensis Benth (MCB) extracts were evaluated. Seven fractions (F0, F10, F20, F30, F40, F50 and MTF) were obtained from the MCB ethanol extracts. Compared to the commercial antioxidants (vitamin C), MTF and F30 exhibited higher antioxidant activities in the antiradical activity test and the FRAP assay. The half-inhibition concentration (IC50) for MTF and F30 were 5.323 µg/mL and 5.278 µg/mL, respectively. MTF at 200 µg/mL significantly decreased the accumulation of TG in oleic acid (OA)-induced HepG2 cells and reversed the inhibitory effect of Compound C on AMPK (MTF and F30 significantly increased the glucose utilization of insulin-induced HepG2 cells). In addition, the components of MTF were identified by HPLC-MS, which were caffeic acid, quercetin 3-O-galactoside, isoquercetin, astragalin, rosmarinic acid, aromadendrin-3-O-rutinoside, rosmarinic acid-3-O-glucoside and kaempferol-7-O-glucoside. Through statistical correlations by Simca P software, it was found that the main antioxidant and hypolipidemic components of MCB might be caffeic acid, kaempferol-7-O-glucoside, rosmarinic acid-3-O-glucoside and aromadendrin-3-O-rutinoside, which may play important roles in the AMPK pathway. MTF and F30 in MCB could be potential health products for the treatment of hyperlipidemia.

Agrimonia pilosa: A Phytochemical and Pharmacological Review

Agrimonia pilosa Ledeb., which belongs to Agrimonia and Rosaceae, is used in traditional Chinese medicine. It exhibits excellent medicinal properties and has been used to treat various diseases, such as tumors, trichomoniasis, vaginitis, diarrhea, and dysentery. Phytochemical studies have revealed that Agrimonia has over 100 secondary metabolites that can be categorized into six classes, i.e., flavonoids, isocoumarins, triterpenes, phloroglucinol derivatives, tannins, and organic acids. This review summarizes recently published literature on the chemical structures of 90 bioactive compounds that have been identified in A. pilosa and examines their pharmacological properties, including their antitumor, anti-inflammatory, antioxidant, antibacterial, and antidiabetic properties, as well as the potential development of parasitic resistance to these chemicals. This review highlights existing knowledge gap and serves as a basis for developing novel preparations of A. pilosa with medicinal value.

Enhanced alleviation of insulin resistance via the IRS-1/Akt/FOXO1 pathway by combining quercetin and EGCG and involving miR-27a-3p and miR-96-5p

Quercetin and EGCG exhibit anti-diabetic and anti-obesity activities, however, their interactive effects in anti-diabetic/anti-obesity actions and underlying mechanisms remain unclear. This study aimed to fill these knowledge gaps. Quercetin, EGCG or their combination attenuated insulin resistance and decreased hepatic gluconeogenesis in high-fat-high-fructose diet (HFFD)-fed C57BL/6 mice and in palmitic acid (PA)-treated HepG2 cells. In mice, supplementation with quercetin (0.05%w/w), EGCG (0.05%w/w) and their combination (quercetin 0.05%+EGCG 0.05%w/w) reduced weight gain and fasting blood glucose and improved serum biochemical parameters. Compare with quercetin/EGCG alone, the quercetin-EGCG combination reduced gluconeogenesis to a greater extent via IRS-1/Akt/FOXO1-mediated down-regulation of downstream PEPCK and G-6-pase. In HepG2 cells, the quercetin (5 μM)-EGCG (5 μM) co-treatment exerted greater suppression on PA-induced changes in glucose and glycogen contents and hexokinase and G-6-pase activities than quercetin/EGCG alone (each 10 μM). The quercetin-EGCG co-treatment reduced glucose production through targeting FOXO1 and inhibiting the transcription of gluconeogenic enzymes. MiR-27a-3p and miR-96-5p regulated directly FOXO1 expression and function, and co-inhibition of miR-27a-3p and miR-96-5p weakened greatly the protective effect of quercetin-EGCG combination. This is the first report on the contributions of miR-27a-3p and miR-96-5p to the synergistic and protective effect of the quercetin-EGCG co-treatment against PA-induced insulin resistance through inhibiting FOXO1 expression.

Hirsutine ameliorates hepatic and cardiac insulin resistance in high-fat diet-induced diabetic mice and in vitro models

Closely associated with type 2 diabetes mellitus (T2DM), hepatic steatosis and cardiac hypertrophy resulting from chronic excess intake can exacerbate insulin resistance (IR). The current study aims to investigate the pharmacological effects of hirsutine, one indole alkaloid isolated from Uncaria rhynchophylla, on improving hepatic and cardiac IR, and elucidate the underlying mechanism. T2DM and IR in vivo were established by high-fat diet (HFD) feeding for 3 months in C57BL/6 J mice. In vitro IR models were induced by high-glucose and high-insulin (HGHI) incubation in HepG2 and H9c2 cells. Hirsutine administration for 8 weeks improved HFD-induced peripheral hyperglycemia, glucose tolerance and IR by OGTT and ITT assays, and simultaneously attenuated hepatic steatosis and cardiac hypertrophy by pathological observation. The impaired p-Akt expression was activated by hirsutine in liver and heart tissues of HFD mice, and also in the models in vitro. Hirsutine exhibited the effects on enhancing glucose consumption and uptake in IR cell models via activating phosphatidylinositol 3-kinase (PI3K)/Akt pathway, which was blocked by PI3K inhibitor LY294002. Moreover, the effect of hirsutine on promoting glucose uptake and GLUT4 expression in HGHI H9c2 cells was also prevented by Compound C, an inhibitor of AMP-activated protein kinase (AMPK). Enhancement of glycolysis might be another factor of hirsutine showing its effects on glycemic control. Collectively, it was uncovered that hirsutine might exert beneficial effects on regulating glucose homeostasis, thus improving hepatic and cardiac IR, and could be a promising compound for treating diet-induced T2DM.

Carpachromene Ameliorates Insulin Resistance in HepG2 Cells via Modulating IR/IRS1/PI3k/Akt/GSK3/FoxO1 Pathway

Insulin resistance contributes to several disorders including type 2 diabetes and cardiovascular diseases. Carpachromene is a natural active compound that inhibits α-glucosidase enzyme. The aim of the present study is to investigate the potential activity of carpachromene on glucose consumption, metabolism and insulin signalling in a HepG2 cells insulin resistant model. A HepG2 insulin resistant cell model (HepG2/IRM) was established. Cell viability assay of HepG2/IRM cells was performed after carpachromene/metformin treatment. Glucose concentration and glycogen content were determined. Western blot analysis of insulin receptor, IRS1, IRS2, PI3k, Akt, GSK3, FoxO1 proteins after carpachromene treatment was performed. Phosphoenolpyruvate carboxykinase (PEPCK) and hexokinase (HK) enzymes activity was also estimated. Viability of HepG2/IRM cells was over 90% after carpachromene treatment at concentrations 6.3, 10, and 20 µg/mL. Treatment of HepG2/IRM cells with carpachromene decreased glucose concentration in a concentration- and time-dependant manner. In addition, carpachromene increased glycogen content of HepG2/IRM cells. Moreover, carpachromene treatment of HepG2/IRM cells significantly increased the expression of phosphorylated/total ratios of IR, IRS1, PI3K, Akt, GSK3, and FoxO1 proteins. Furthermore, PEPCK enzyme activity was significantly decreased, and HK enzyme activity was significantly increased after carpachromene treatment. The present study examined, for the first time, the potential antidiabetic activity of carpachromene on a biochemical and molecular basis. It increased the expression ratio of insulin receptor and IRS1 which further phosphorylated/activated PI3K/Akt pathway and phosphorylated/inhibited GSK3 and FoxO1 proteins. Our findings revealed that carpachromene showed central molecular regulation of glucose metabolism and insulin signalling via IR/IRS1/ PI3K/Akt/GSK3/FoxO1 pathway.

Aegle marmelos Leaf Extract Phytochemical Analysis, Cytotoxicity, In Vitro Antioxidant and Antidiabetic Activities

For many years, Aegle marmelos (A. marmelos) has been used medicinally and as a dietary supplement. Despite this, there are minimal research data on A. marmelos phytochemical properties and pharmacological effects. This study aimed to explore the phytoconstituents, cytotoxicity, glucose uptake, and antioxidant and antidiabetic potential of an alcoholic extract of A. marmelos leaf. The cytotoxicity of A. marmelos in HepG2 cells was tested in vitro, and the results revealed that it has strong cytocompatibility and cytoprotective properties. The extract's antioxidant activities were investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods. Antioxidant potential was shown to be quite impressive. The enzymes α-amylase and α-glycosidase were found to be substantially inhibited by A. marmelos, with IC₅₀ values of 46.21 and 42.07 mg/mL, respectively. In HepG2 cells, A. marmelos significantly reduced ROS levels that were elevated due to high glucose and enhanced glucose consumption (p < 0.05). These activities might be due to the enrichment of bioactive phytoconstituents analyzed chromatographically using GC/MS and HPLC. The findings of this study show that A. marmelos could be an effective restorative therapy for diabetes and related diseases.

Antioxidant, Anti-Inflammatory, and Antidiabetic Activities of Bioactive Compounds from the Fruits of Livistona chinensis Based on Network Pharmacology Prediction

In this study, a chemical investigation on the fruits of Livistona chinensis (FLC) led to the isolation and identification of 45 polyphenols and 5 alkaloids, including two new compounds (Livischinol (1) and Livischinine A (46)), an undescribed compound (47) and 47 known compounds. FLC was predicted with novel potential antidiabetic function by collecting and analyzing the potential targets of the ingredients. Compound 32 exhibited significant α-glucosidase inhibitory activity (IC₅₀ = 5.71 μM) and 1, 6, and 44 showed the PTP1B inhibitory activity with IC₅₀ values of 9.41-22.19 μM, while that of oleanolic acid was 28.58 μM. The competitive inhibitors of PTP1B (compounds 1 and 44) formed strong binding affinity, with catalytic active sites, proved by kinetic analysis, fluorescence spectra measurements, and computational simulations, and stimulated glucose uptake in the insulin-resistant HepG2 cells at the dose of 50 μM. In addition, FLC was rich in antioxidant and anti-inflammatory bioactive compounds so that they could be developed as nutraceuticals against diabetes.

Ultrasound-assisted enzymatic extraction of Corni Fructus alpha-glucosidase inhibitors improves insulin resistance in HepG2 cells

Corni Fructus (CF) is a traditional medicine and beneficial food with multifaceted protective effects against diabetes and its complications. Since alpha-glucosidase inhibitors (GIs) are promising first-choice oral antihyperglycemic drugs for diabetes, we examined whether GIs from CF (GICF) are useful for diabetes treatment. Therefore, GICF was extracted by ultrasound-assisted enzymatic extraction (UAEE) that is optimized by a three-level, four-factor Box-Behnken design and determined by ultra-performance liquid chromatography. Compared to 36.31 mg g^-1 without enzyme treatment, the GICF yield increased to 70.44 mg g^-1via UAEE under optimum conditions (0.5% compound enzyme extracted in 23 min at 46 °C and pH 4.8). The activity (91.99%) of GICF was as predicted (93.28%). When GICF was used in an insulin-resistant HepG2 cell model, it significantly ameliorated the glucose metabolism in a dose-dependent manner. Our findings indicate that UAEE may be an innovative method for functional food extraction and a potential strategy for high-quality food ingredient (such as GI) production with high efficiency and productivity.

Modulating effects of capsaicin on glucose homeostasis and the underlying mechanism

Abnormal glucose homeostasis is linked to a variety of metabolic syndromes, such as insulin resistance, obesity, type-2 diabetes mellitus, hypertension and cardiovascular diseases. Maintenance of normal glucose homeostasis is important for the body to keep normal biological functions. As the major bioactive ingredient in chili peppers responsible for the pungent flavor, capsaicin has been reported to effectively improve glucose homeostasis with low cytotoxicity. In this review, the modulating effects of capsaicin on glucose homeostasis in cell models, animal models and human trials are summarized through both TRPV1 dependent and TRPV1 independent pathways. The relevant molecular mechanisms underlying its regulatory effects are also evaluated. Understanding the effects and mechanisms of capsaicin on glucose metabolism could provide theoretical evidence for its application in the food and pharmaceutical industries.

Activated AMPK promoted the decrease of lactate production in rat Sertoli cells exposed to Zearalenone

Zearalenone, which is ubiquitous in grains and animal feed, is a mycotoxin that can cause serious damage to animals and humans. Sertoli cells (SCs) can be used to study ZEA male reproductive toxicity in vitro. SCs provide energy for germ cells, where AMPK regulates intracellular energy. In order to explore the regulatory effect of AMPK on ZEA-induced lactate decline, we activated AMPK by AICAR and then inhibited AMPK by Compound C with ZEA-treated SCs for 24 h to detect intracellular lactate production-related indicators. Cell viability in the presence of 20 μmol/L ZEA and either 50 μmol/L AICAR or 5 μmol/L Compound C, respectively, did not damage SCs, and could effectively either activate or inhibit AMPK. Inhibition of AMPK promoted the production of pyruvate and lactate via increased expression of the glycolysis-related genes Pgam1 and the lactate production-related proteins GLUT1, LDHA, and MCT4. Activating AMPK inhibited the production of lactate and pyruvate by suppressing the expression of glycolysis-related genes HK1, Pgam1, and Gpi1 and that of lactate production-related proteins LDHA and MCT4. Zearalenone destroys the energy balance in SCs, activates P-AMPK, which inhibit the production of lactate and pyruvate in SCs. This also leads to the decrease of energy supply of SCs to spermatogenic cells, damages to reproductive system.

Perfluorooctanesulfonic Acid (PFOS) Thwarts the Beneficial Effects of Calorie Restriction and Metformin

A combination of calorie restriction (CR), dietary modification, and exercise is the recommended therapy to reverse obesity and nonalcoholic fatty liver disease. In the liver, CR shifts hepatic metabolism from lipid storage to lipid utilization pathways, such as AMP-activated protein kinase (AMPK). Perfluorooctanesulfonic acid (PFOS), a fluorosurfactant previously used in stain repellents and anti-stick materials, can increase hepatic lipids in mice following relatively low-dose exposures. To test the hypothesis that PFOS administration interferes with CR, adult male C57BL/6N mice were fed ad libitum or a 25% reduced calorie diet concomitant with either vehicle (water) or 100 μg PFOS/kg/day via oral gavage for 6 weeks. CR alone improved hepatic lipids and glucose tolerance. PFOS did not significantly alter CR-induced weight loss, white adipose tissue mass, or liver weight over 6 weeks. However, PFOS increased hepatic triglyceride accumulation, in both mice fed ad libitum and subjected to CR. This was associated with decreased phosphorylated AMPK expression in liver. Glucagon (100 nM) treatment induced glucose production in hepatocytes, which was further upregulated with PFOS (2.5 μM) co-treatment. Next, to explore whether the observed changes were related to AMPK signaling, HepG2 cells were treated with metformin or AICAR alone or in combination with PFOS (25 μM). PFOS interfered with glucose-lowering effects of metformin, and AICAR treatment partially impaired PFOS-induced increase in glucose production. In 3T3-L1 adipocytes, metformin was less effective with PFOS co-treatment. Overall, PFOS administration disrupted hepatic lipid and glucose homeostasis and interfered with beneficial glucose-lowering effects of CR and metformin.

Flavonoids from Hypericum patulum enhance glucose consumption and attenuate lipid accumulation in HepG2 cells

Hypericum patulum has been used as a folk medicine for its varied therapeutic effects including antifungal, wound-healing, spasmolytic, stimulant, hypotensive activities. The water decoction is drank as tea could treat cold, infantile malnutrition. The present study aims to isolate the constituents of the plant and investigate their effects on the glucose consumption in insulin-resistant HepG2 cells, furthermore, lipid metabolism in oleic acid (OA)-treated HepG2 cells was also studied. The phytochemical investigation of the plant led to the isolation of eleven compounds, and their structures were identified by spectroscopic analysis as n-dotriacontanol (1), shikimic acid (2), 1-O-caffeoylquinic acid methyl ester (3), 5-O-caffeoylquinic acid methyl ester (4), 5-O-coumaroylquinic acid methyl ester (5), 5-O-caffeoylquinic acid butyl ester (6), quercetin-3-O-α-L-rhamnoside (7), quercetin (8), quercetin-3-O-(4״-methoxy)-α-L-rahmnopyranosyl (9), hyperoside (10), and rutin (11). The results revealed that compounds 7, 9, and 10 could enhance glucose consumption significantly in hyperglycemia induced HepG2 cells and insulin-resistant HepG2 cells. In addition, the western blotting analysis result exhibited that compounds 7, 9, and 10 in high concentration (5 μM, H) group could dramatically upregulate the expression of PPARγ protein, and even the effect of them had no significant difference compared with that of rosiglitazone. Furthermore, compounds 9 and 10 in middle concentration (2.5 μM, M) group and H group could dramatically promote triglyceride metabolism and decrease TG content in OA-treated HepG2 cells, and even in H group, reactive oxygen species (ROS) level were significantly decreased compared with model group. PRACTICAL APPLICATIONS: Hypericum patulum is a well-known plant of the genera Hypericum for its varied preventive and therapeutic potential activities. To study the chemical constituents and their effects on glucose and lipid metabolism in vitro, we detected glucose consumption in insulin-resistant HepG2 cells, triglyceride content and reactive oxygen species level in OA-treated HepG2 cells. In addition, PPARγ protein was also detected by western blotting analysis in the study. Compounds 1, 2, 3, 5, 6, 9, 10, and 11 were isolated from the plant for the first time. Quercetin-3-O-(4"-methoxy)-α-L-rahmnopyranosyl (9) and hyperoside (10) had potential therapeutic benefit against glucose and lipid metabolic disease. Therefore, this study might have certain guiding significance for further research and development of H. patulum.

Analysis of polyphenols in Aegle marmelos leaf and ameliorative efficacy against diabetic mice through restoration of antioxidant and anti-inflammatory status

The biomedical survey reports edible plant Aegle marmelos has been utilized for centuries by tribal communities in India as a dietary supplement for the management of diabetes. Herein, we have investigated cytotoxicity, cytoprotective and antidiabetic activity of characterized alkaloid-free hydroalcoholic extract of A. marmelos (AFEAM; 200 and 400 mg/kg). Identification of polyphenols and quantification of major compounds were done using UPLC-MS and HPTLC, respectively. AFEAM showed good cytocompatibility and cytoprotective potential against oxidative stress induced by hyperglycemia in HepG₂ cells. The AFEAM intake had significantly ameliorated the serum blood glucose level, state of dyslipidemia, level of pro-inflammatory markers (tumor necrosis factor-α, interleukin-6, and interleukin-1β), and antioxidant (superoxide dismutase, catalase, glutathione peroxidase, and malondialdehyde) status in diabetic mice. Histological examination of the treated groups showed amelioration of damaged pancreas, liver, and kidney tissues. Conclusively, AFEAM intake might be promising dietary supplements for prediabetics as well as an adjuvant to modern treatment in diabetics. PRACTICAL APPLICATIONS: Different reports have been published on Aegle marmelos but as per our understanding till date, no study has been reported on the amelioration of diabetes due to alkaloid free hydroalcoholic extract of A. marmelos /polyphenolic content in the animal model. The result of this study indicated that A. marmelos supplementation effectively ameliorates diabetes through the restoration of antioxidant and anti-inflammatory status. This study has collated sufficient scientific evidence for the dietary application of A. marmelos in society especially for prediabetics, however, it can also be used as an adjuvant to modern treatments in diabetics.

(Poly)phenol-Rich Diets in the Management of Endothelial Dysfunction in Diabetes Mellitus: Biological Properties in Cultured Endothelial Cells

Processed and ready-to-eat foods become routinely consumed resulting in a sharp rise of sugar intake in people's daily diets. The inclusion of fresh fruits and vegetables rich in (poly)phenols has been encouraged by the World Health Organization (WHO) as part of the daily choices to ameliorate endothelial dysfunction and ease the socio-economic burden of diabetes. Research in Food, Nutrition, and Cell Metabolism areas is revealing that the health benefits of (poly)phenol-rich foods go beyond their antioxidant properties and are in fact key modulators of redox and glycaemia status, and inflammatory response contributing to improved endothelial function and vascular health in diabetes. Other beneficial aspects include appetite modulation, regulation of hydrolytic enzymes involved in sugar and lipid metabolism, and mediation of cell-cell aggregation events. This work overviews the current knowledge on the biological properties of ingested (poly)phenols in cultured endothelial cells with emphasis on the circulating (poly)phenols, providing support to (poly)phenol-rich diets as alternatives to drug-based therapies in the prevention, treatment, and management of diabetes. A critical evaluation on the caveats and challenges involve in current experimental cell-based designs and approaches adopted is also discussed.

Limonoids isolated from fruits of Swietenia macrophylla king enhance glucose consumption in insulin-resistant HepG2 cells via activating PPARγ

The fruits of Swietenia macrophylla King have been processed commercially to a variety of health foods and healthcare products and exhibited antidiabetic, anti-inflammatory, antimutagenicity, antitumor activity, and so on. This study was aimed to examine the glucose consumption in human hepatoma HepG2 cells and the expression of PPARγ of limonoids isolated from the fruits of S. macrophylla. The phytochemical investigation of the fruits led to the isolation of ten limonoids which structures were elucidated by spectroscopic analysis as swietenine (1), khayasin T (2), 6-deoxyswietenine (3), 3-O-tigloylswietenolide (4), swietenolide (5), 3,6-O,O-diacetylswietenolide (6), 7-deacetoxy-7-oxogedunin (7), fissinolide (8), proceranolide (9), 7-deacetoxy-7α-hydroxygedunin (10), and compound 10 was isolated from this plant for the first time. The glucose consumption assay revealed that compounds 1, 2, 3, 5, and 9 could promote glucose consumption significantly in normal hyperglycemia-induced HepG2 cells, furthermore, compounds 1, 5, and 9 had a better effect on promoting glucose consumption in insulin-resistant HepG2 cells. In addition, compounds 1 and 5 could dramatically enhance the expression of PPARγ protein in insulin-resistant HepG2 cells according to the western blotting analysis result. PRACTICAL APPLICATIONS: Swietenia macrophylla King belongs to the family Meliaceae and the fruits have been exhibited a wide range of biological activities, such as antidiabetic, anti-inflammatory, antimutagenicity, antitumor activity, and so on. Phytochemical investigations of S. macrophylla have revealed that limonoids and triterpenoids were effective antidiabetic agents. However, the mechanism of these limonoids to antidiabetic activity is unclear. In this study, limonoids were isolated from the fruit of S. macrophylla and their effects on the glucose consumption of insulin-resistant HepG2 cells were studied. The results showed that compounds 1 and 5 could dramatically enhance the expression of PPARγ protein in insulin-resistant HepG2 cells, which will give aid to explore the mechanism of these limonoids in the treatment of type 2 diabetes. Therefore, this research might facilitate further research and development of S. macrophylla.

Dietary Luteolin: A Narrative Review Focusing on Its Pharmacokinetic Properties and Effects on Glycolipid Metabolism

Luteolin, a flavone subclass of flavonoids, is commonly found in food plants and has multiple biological activities. Recently, evidence is growing with regard to the potential of luteolin intake to beneficially affect glycolipid metabolism disorders (GLMDs), particularly insulin resistance, diabetes, and obesity. The aim of this contribution is to provide an overview of recent advances in identifying and understanding the pharmacokinetic properties (absorption, metabolism, and bioavailability) of luteolin, its regulatory effects on glycolipid metabolism, and the underlying mechanisms of action of luteolin in the brain, liver, adipose tissues, and other tissues/organs. Collectively, luteolin or its principal metabolites may contribute to counteracting GLMDs, especially for human obesity and diabetes.

Plants from the genus Eugenia as promising therapeutic agents for the management of diabetes mellitus: A review

This review combined scientific data regarding the use of genus Eugenia plants for the management of diabetes. Diabetes mellitus is a chronic metabolic disease mainly characterized by hyperglycaemia, which can lead to serious health complications. Scientists have been seeking therapeutic compounds in plants, reporting the species of the genus Eugenia as a potential source of phytochemicals with antidiabetic properties. In vitro and in vivo studies have proved that the bioactive compounds in the genus Eugenia can positively affect the biomarkers of diabetes. We discussed the phytochemical profile of the genus Eugenia and its mechanism of action on diabetes, which could modulate carbohydrate metabolism, glucose homeostasis, and insulin secretion, inhibit carbohydrases and reduce oxidative stress, suppressing the formation of advanced glycation end-products and protecting/regenerating pancreatic β-cells. Therefore, plants of the genus Eugenia showed therapeutic potential to be used in the treatment of diabetes and its comorbidities.

Dietary Ginsenoside T19 Supplementation Regulates Glucose and Lipid Metabolism via AMPK and PI3K Pathways and Its Effect on Intestinal Microbiota

Ginseng, as a functional food, is widely used worldwide because of its multifarious benefits. Studies have verified that 25-hydroxyl-protopanaxatriol (T19) is a new ginsenoside from ginseng, which had an important inhibitory effect on α-glucosidase and protein tyrosine phosphatase 1B in vitro. This study aims to assess the regulation of T19 against glycolipid metabolism by insulin-resistant HepG2 cells and diabetes mice induced with high-fat diet combined with streptozotocin (STZ). T19 effectively lowered the levels of blood glucose and lipid, alleviated insulin resistance, and improved histological pathology of liver and pancreas. Further study demonstrated that regulation of AMP-activated protein kinase- and phosphoinositide-3-kinase-signaling pathways was involved in the potential mechanism of T19 efficiency. Simultaneously, high-throughput sequencing of 16S rDNA revealed that T19 remarkably ameliorated the high-fat diet/STZ-induced disorders of intestinal microbiota by decreasing the value of Firmicutes/Bacteroidetes, and remarkably raised the relative abundance of the Lachnospiraceae family, which are the beneficial bacteria that can regulate glucose and lipid metabolism. The results may provide clues for further understanding the mechanism of T19 in regulating glycolipid metabolism, and may provide a scientific basis for ginseng as a potential dietary food to prevent metabolic diseases.

Pelargonidin-3-O-glucoside Derived from Wild Raspberry Exerts Antihyperglycemic Effect by Inducing Autophagy and Modulating Gut Microbiota

Increasing evidence indicates that anthocyanins exert beneficial effects on type 2 diabetes (T2D), but the underlying mechanism remains unclear. Herein, the hyperglycemia-lowering effect of Pg3G derived from wild raspberry was investigated on high-glucose/high-fat (HG+HF)-induced hepatocytes and db/db diabetic mice. Our results indicated that Pg3G promoted glucose uptake in HG+HF-induced hepatocytes. Moreover, Pg3G induced autophagy, whereas autophagy inhibitors blocked the hypoglycemic effect of Pg3G. Transcriptional factor EB (TFEB) was found to be linked to Pg3G-induced autophagy. In vivo study showed that Pg3G treatment contributed to the improvement of glucose tolerance, insulin sensitivity, and induction of autophagy. Furthermore, Pg3G not only modified the gut microbiota composition, as indicated by an increased abundance of Prevotella, and elevated Bacteroidetes/Firmicutes ratio, but also strengthened the intestinal barrier integrity. This study unveils a novel mechanism that Pg3G attenuates hyperglycemia through inducing autophagy and modulating gut microbiota, which implicates a potential nutritional intervention strategy for T2D.

Exopolysaccharides from probiotic bacteria and their health potential

Exopolysaccharides (EPS) are extracellular macromolecules excreted as tightly bound capsule or loosely attached slime layer in microorganisms. They play most prominent role against desiccation, phagocytosis, cell recognition, phage attack, antibiotics or toxic compounds and osmotic stress. In the last few decades, natural polymers have gained much attention among scientific communities owing to their therapeutic potential. In particular the EPS retrieved from probiotic bacteria with varied carbohydrate compositions possess a plenty of beneficial properties. Different probiotic microbes have unique behavior in expressing their capability to display significant health promoting characteristics in the form of polysaccharides. In this new era of alternative medicines, these polysaccharides are considered as substitutes for synthetic drugs. The EPS finds applications in various fields like textiles, cosmetics, bioremediation, food and therapeutics. The present review is focused on sources, chemical composition, biosynthetic pathways of EPS and their biological potential. More attention has been given to the scientific investigations on antimicrobial, antitumor, anti-biofilm, antiviral, anti-inflammatory and immunomodulatory activities.

Inhibition of Digestive Enzyme and Stimulation of Human Liver Cells (HepG2) Glucose Uptake by Date Seeds Extract

Type 2 diabetes mellitus is increasing worldwide, and the United Arab Emirates is presenting one of the world's highest prevalence rates. Dietary polyphenols exert an antidiabetic effect by modulating carbohydrates digestion and cellular glucose uptake. Due to their particularly high content in polyphenols, date seeds represent a potential antidiabetic agent. This study aims to determine if date seed polyphenols inhibit the activity of the enzymes (α-amylase and α-glucosidase), responsible for the digestion of carbohydrates and modulating the glucose uptake by human liver cells. In vitro activity of the intestinal α-glucosidase, pancreatic α-amylase, the glucose uptake by HepG2 cells, and the expression of GLUT4 and AMPK analyzed by western blotting (with and without date seeds extract). Our result showed that the maximum enzymes inhibition was obtained with 400 μg/mL and 900 μg/mL DSE for α-amylase and α-glucosidase, respectively. The HepG2 cell viability significantly decreased up to 80% at 4000 μg/mL DSE. The expression of GLUT4 was higher at 100 μg/mL DSE (with insulin and without insulin). However, the expressions of P-AMPK and AMPK were increased by DSE, mainly in a non-insulin-dependent manner. Therefore, DSE, by inhibiting carbohydrate digestion and stimulating glucose uptake by HepG2, can potentially demonstrate the therapeutic potential for diabetes management.

Policosanol profiles and adenosine 5'-monophosphate-activated protein kinase (AMPK) activation potential of Korean wheat seedling extracts according to cultivar and growth time

Policosanols is a health promoting aliphatic alcohol known as lipid-lowing agent. To enable maximising the functional properties of wheat, this research investigates the policosanol profiles and adenosine 5'-monophosphate-activated protein kinase (AMPK) activation potential of Korean wheat seedlings according to cultivars and growth times. GC-MS revealed six policosanols that differed markedly in content between 17 cultivars, especially, octacosanol (8) showed the most predominant component (49-83%), varying significantly in average concentrations with growth times as 361.4 (3 days) → 613.0 (6 days) → 203.1 (9 days) → 196.5 (12 days) → 50.9 mg/100 g (19 days). The highest average policosanol (738.7 mg/100 g) exhibited after 6 days, while the lowest was 104.4 mg/100 g on 19 days. Moreover, the wheat cultivars including Shinmichal 1, Anbaek, Namhae, and Joah at 6 days may be recommended as potential sources because of high policosanols (921.7-990.6 mg/100 g). Western blot analysis revealed markedly higher AMPK activation in cells treated with the hexane extracts (150-370% at 100 μg/ml) and octacosanol (8) possessed potent AMPK activator (control; 100 → 280% at 200 μg/ml). It is confirmed that the AMPK activation by wheat seedlings are positively related to the highest policosanol content at the 6 days of growth time, independent of the cultivar. Our results may be contributed to enhance the wheat value regarding development of new cultivars and functional foods.

Cultivated Fruit Body of Phellinus baumii: A Potentially Sustainable Antidiabetic Resource

Previous studies have been reported that the fruit body of wild Phellinus baumii alleviates diabetes, and antioxidants are beneficial to diabetes by protecting the β-cell from damage due to oxidative stress. Large-scale cultivation of P. baumii fruit body has been successful in the past decade. This paper aimed to investigate whether the fruit body of the cultivated P. baumii has the same analogical effects as the wild. The cultivated P. baumii fruit body was extracted by 80% of ethanol extracts, and different fractions were obtained with the successive use of petroleum ether, ethyl acetate (EtOAc), n-butanol (n-BuOH), and water, which yielded 15.98 ± 1.56, 1.74 ± 0.34, 3.31 ± 0.41, 4.12 ± 0.37, and 1.38 ± 0.26% extract recovery, respectively. Results show that the EtOAc fraction exhibits the highest inhibitory effect on α-glucosidase activity (IC50 = 49.05 ± 3.14 μg mL-1), which is an order of magnitude higher than the positive control (acarbose, IC50 = 645.73 ± 7.86 μg mL-1). It was mainly composed of phenolic compounds with a purity of 79.45% and characterized by liquid chromatography-mass spectrometry as osmudacetone, hispidin, davallialactone, 2,5-bis(4,7-dihydroxy-8-methyl-2-oxo-2H-chromen-3-yl)cyclohexa-2,5-diene-1,4-dione, hypholomin B, and inoscavin A. Furthermore, the EtOAc fraction increased the glucose consumption of insulin-resistant HepG2 cells at a concentration range of 25-100 μg mL-1. The EtOAc fraction also demonstrated antioxidant activities by scavenging 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt, and hydroxyl radicals. In conclusion, the EtOAc fraction of the cultivated P. baumii fruit body exerted effective antidiabetic effects, possibly due to the high content of selective phenolic compounds. Hence, the cultivated fruit body of P. baumii can be a sustainable resource for treating diabetes, and our work also shed some light on its future utilization.

Enhancement of glucose homeostasis through the PI3K/Akt signaling pathway by dietary with Agaricus blazei Murrill in STZ-induced diabetic rats

Agaricus blazei Murrill (ABM) is an edible fungus. This study investigated the protective role of ABM fruiting body against streptozotocin (STZ)-induced diabetic rats. After 4 weeks of ABM supplement, glucose homeostasis was improved in diabetic rats. Quantitative real-time and Western blot analyses suggested that ABM could promote the gene and protein expression level of insulin receptor, pyruvate dehydrogenase kinase, phospho-kinase B, kinase B, phosphatidylinositol 3-kinase, insulin receptor substrate 1, glucose transporter-4, and glutamine synthetase, while inhibiting the expression of glycogen synthase kinase 3β and c-jun N-terminal kinase 1 and 2. According to multivariate and univariate statistical analysis, liver metabolite profiles of the normal and diabetic rats fed basal and experimental diet were clearly separated. The differential liver metabolites from diabetic rats fed basal and ABM diet-related pathways including the glycolysis pathway, pentose phosphate pathway, tricarboxylic acid cycle, and oxidative phosphorylation were analyzed. A total of 18 potential biomarker metabolites were identified as differential biomarkers associated with ABM supplement diet.

Assessment of antioxidant and antidiabetic properties of Agaricus blazei Murill extracts

Agaricus blazei Murill (ABM), a medicinal mushroom, has beneficial effects on various human metabolic diseases. The objective of this research was to evaluate the antioxidant and antidiabetic properties of ABM extracts (ethanol extract and ethyl acetate extract). The antioxidant activities of ABM ethanol extract (EE) and ethyl acetate extract (EA) were analyzed using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and hydroxyl radical scavenging assays and the reducing power using K3Fe(CN)6 in vitro. Moreover, the effects of EE and EA on α-glucosidase inhibitory activity and improving glucose uptake by HepG2 cells were investigated in vitro. The EA showed stronger antioxidant activity, as well as inhibition of α-glucosidase, compared to EE. The analysis of glucose uptake by HepG2 cells showed that EA had significant glucose-lowering activity and exhibited no difference compared to metformin. The results suggest that ABM extracts could improve the glucose uptake by HepG2 cells and thereby alleviate postprandial hyperglycemia. This investigation provides a strong rationale for further studies on the application of ABM to control type 2 diabetes.

Identification of Cyanidin-3-arabinoside Extracted from Blueberry as a Selective Protein Tyrosine Phosphatase 1B Inhibitor

Protein tyrosine phosphatase 1B (PTP1B) is an important target for type 2 diabetes. PTP1B inhibitors can reduce blood glucose levels by increasing insulin sensitivity. Anthocyanins often play a hypoglycemic effect, but the research about them have mainly focused on glucosidase. At present, the research about protein tyrosine phosphatase 1B (PTP1B) target is less, and the corresponding molecular mechanism is still unclear. Therefore, in this present study, anthocyanins isolated from blueberry were used to study the inhibitory activity on PTP1B. The isolated cyanidin-3-arabinoside (Cya-3-Ara) exhibited a better inhibitory activity with IC₅₀ = 8.91 ± 0.63 μM, which was higher than the positive control (oleanolic acid, IC₅₀ = 13.9 ± 1.01 μM), and the mechanism of PTP1B inhibition was reversible mixed pattern. The structure-activity relationship (SAR) between anthocyanins and PTP1B inhibition was investigated. The enzyme activity inhibition and molecular docking showed that anthocyanins had high selectivity for PTP1B inhibition. Further study showed that Cya-3-Ara could promote glycogen synthesis through ameliorating PTP1B-involved IRS-1/PI3K/Akt/GSK3β pathways. Cya-3-Ara could also be regarded as a synergistic inhibitor (CI ≤ 0.54) of oleanolic acid to obtain a better inhibitory effect on PTP1B. Taken together, our study clearly illustrates the SAR between anthocyanins and PTP1B inhibition and the mechanism of Cya-3-Ara in the insulin signaling pathway.

Production of triterpenoid compounds from Ganoderma lucidum spore powder using ultrasound-assisted extraction

When ingested as a dietary supplement, Ganoderma lucidum spore powders (GLSP) provide various health benefits such as enhanced immunity, liver protection and anti-cancer effects. In this study, triterpenoid extraction from GLSP was achieved using an ultrasound-assisted process which was optimized using response surface methodology (RSM). Ultrasound-assisted extraction (UAE) was also compared to the most conventional chemical extraction method. For UAE, optimum extraction conditions were found to be ethanol concentration = 95% v/v; solvent to solid ratio = 50:1 mL/g; ultrasound time = 5.4 min; ultrasound power = 564.7 w, and ultrasound probe distance = 8.2 cm. At optimal UAE conditions, no significant differences were found between experimental (0.97 ± 0.04 %) and predicted values (99%); which indicates appreciable correlation at the 97% confidence interval. The findings show the application of Box-Behnken design (BBD) to predict and optimize triterpenoid yield for UAE of triterpenoid from GLSP. Furthermore, glucose consumption was 2.68 times that of control samples when tested with insulin-resistant HepG2 cell, showing potential use in type 2 diabetes. In addition, triterpenoid extracts show good biocompatibility and inhibition of antioxidant activity.