Recent Updates on Phytoconstituent Alpha-Glucosidase Inhibitors: An Approach towards the Treatment of Type Two Diabetes

Novel carbazole-oxadiazole derivatives as anti-α-glucosidase and anti-α-amylase agents: Design, synthesis, molecular docking, and biological evaluation

To find novel inhibitors of α-glucosidase and α-amylase, a series of new carbazole-oxadiazole derivatives (6a-6n) were prepared, and screened for their anti-α-glucosidase and anti-α-amylase effects. Most of the tested derivatives showed different degrees of α-glucosidase and α-amylase inhibitory activity (IC50: 21.39 ± 0.69-92.05 ± 1.54 μM, 45.53 ± 1.50-126.14 ± 6.33 μM, respectively) compared to the standard acarbose (IC50: 427.00 ± 9.56 μM, 24.68 ± 1.10 μM, respectively). Thereinto, 6c (IC50 = 21.39 ± 0.69 μM) displayed the most effective anti-α-glucosidase activity and 6e presented the best anti-α-amylase activity with an IC50 value of 45.53 ± 1.50 μM. Lineweaver-Burk plot analysis suggested that 6c and 6e behaved as mixed α-glucosidase inhibitor and mixed α-amylase inhibitor, respectively. The results of circular dichroism, atomic force microscope, and molecular docking simulation exposed interaction mechanisms between two preferred compounds (6c and 6e) and their corresponding enzymes. Combined with the possible properties of reducing the elevation in postprandial blood glucose, oral activity, positive bioavailability, and low cytotoxicity of 6c and 6e, it could be concluded that the target derivatives may be able to act as lead molecules for the development of new hypoglycemic agents.

Anti-diabetes and neuroprotection potential and primary safety studies of Isatis tinctoria L. hydroalcoholic leaf extract

PURPOSE

Natural plant raw materials, previously underestimated in therapeutics, are becoming the subject of research for new applications in medicine. In our research, the hydroalcoholic extract of Isatis tinctoria leaf, rich in flavonoid compounds such as vicenin-2 and quercetin, was examined as a potential antidiabetic and neuroprotective agent.

METHODS

The effect of the extract and its main flavonoid compounds on protein glycation, alpha-glucosidase activity, and acetylcholinesterase activity was tested. In vitro, in the mouse hippocampal neuronal cell line and in vivo, using a mouse model, the safety of the extract was screened for.

RESULTS

Our experiments demonstrated significant inhibition of protein glycation, alpha-glucosidase activity, acetylcholinesterase activity, and β-amyloid aggregation by the extract, in a concentration-dependent manner. The extract had a strong reducing effect and did not exhibit cytotoxicity up to a concentration of 25 mg/mL. Intraperitoneal administration of the extract to mice did not have negative effects on body mass, locomotor activity, coordination, and liver cell integrity.

CONCLUSIONS

Our research sheds new light on this raw material and deepens knowledge of its activity. This may result in the recognition of its therapeutic effects and even in its introduction in the modern treatment of diseases characterized by pathological changes associated with hyperglycemia, oxidation, and inflammation.

Deciphering the Potential Therapeutic Effects of Hydnocarpus wightianus Seed Extracts using in vitro and in silico approaches

Phytocompounds possess the potential to treat a broad spectrum of disorders due to their remarkable bioactivity. Naturally occurring compounds possess lower toxicity profiles, which making them attractive targets for drug development. Hydnocarpus wightianus seeds were extracted using ethanol, acetone, and hexane solvents. The extracts were evaluated for phytochemicals screening and other therapeutic characteristics, such as free radicals scavenging, anti α-amylase, anti α-glucosidase, and anti-bacterial activities. The ethanolic extract exhibited noteworthy antibacterial characteristics and demonstrated considerable antioxidant, and anti-diabetic effects. The IC50 value of the ethanolic extract for Dpph, α-amylase, and α-glucosidase were found to be 77.299 ± 3.381 μg/mL, 165.56 2.56 μg/mL, and 136.58 ± 5.82 μg/mL, respectively. The ethanolic extract was effective against Methicillin resistant Staphylococcus aureus (26 mm zone of inhibition at 100 μL concentration). Molecular docking investigations revealed the phytoconstituent's inhibitory mechanisms against diabetic, free radicals, and bacterial activity. Docking score for phytocompounds against targeted protein varies from -7.2 to -5.1 kcal/mol. The bioactive compounds present in the ethanolic extract were identified by Gas chromatography/Mass spectrometry analysis, followed by molecular docking and molecular dynamic simulation studies to further explore the phytoconstituent's inhibitory mechanism of α-glucosidase, ∝-amylase, radical scavenging, and bacterial activity. The electronic structure and possible pharmacological actions of the phytocompound were revealed through the use of Density Functional Theory (DFT) analysis. Computational and in vitro studies revealed that these identified compounds have anti-diabetic, anti-oxidant, and anti-bacterial activities against antibiotic-resistant strain of Staphylococcus aureus.

Highly Soluble β-Glucan Fiber Modulates Mechanisms of Blood Glucose Regulation and Intestinal Permeability

β-glucans found in cereal grains have been previously demonstrated to improve blood glucose control; however, current understanding points to their high viscosity as the primary mechanism of action. In this work, we present a novel, highly soluble, low-viscosity β-glucan fiber (HS-BG fiber) and a preclinical dataset that demonstrates its impact on two mechanisms related to the prevention of hyperglycemia. Our results show that HS-BG inhibits the activity of two key proteins involved in glucose metabolism, the α-glucosidase enzyme and the SGLT1 transporter, thereby having the potential to slow starch digestion and subsequent glucose uptake. Furthermore, we demonstrate in a multi-donor fecal fermentation model that HS-BG is metabolized by several different members of the gut microbiome, producing high amounts of short-chain fatty acids (SCFAs), known agonists of GPR43 receptors in the gut related to GLP-1 secretion. The production of SCFAs was verified in the translational gut model, SHIME®. Moreover, HS-BG fiber fermentation produces compounds that restored permeability in disrupted epithelial cells, decreased inflammatory chemokines (CXCL10, MCP-1, and IL-8), and increased anti-inflammatory marker (IL-10), which could improve insulin resistance. Together, these data suggest that the novel HS-BG fiber is a promising new functional ingredient that can be used to modulate postprandial glycemic responses while the high solubility and low viscosity enable easy formulation in both beverage and solid food matrices.

A Novel Nutraceutical Supplement Lowers Postprandial Glucose and Insulin Levels upon a Carbohydrate-Rich Meal or Sucrose Drink Intake in Healthy Individuals-A Randomized, Placebo-Controlled, Crossover Feeding Study

BACKGROUND

Alkaloid- and polyphenol-rich white mulberry leaf and apple peel extracts have been shown to have potential glucose-lowering effects, benefitting the control of postprandial blood glucose levels. This study aimed to determine the effect of the combination of Malus domestica peel and Morus alba leaf extracts (GLUBLOCTM) on postprandial blood glucose and insulin-lowering effects in healthy adults after a carbohydrate-rich meal or sucrose drink intake.

METHODS

This study was designed as a randomized, crossover, single-blinded clinical trial. Out of 116 healthy participants, 85 subjects (aged 18-60 years) completed the day 1 and 5 crossover study. On day 1, subjects were supplemented with a placebo or GLUBLOCTM tablet 10 min before the carbohydrate-rich meal (300 g of tomato rice) or sucrose drink intake (75 g of sucrose dissolved in 300 mL water). On day 5, the treatments were crossed over, and the same diet was followed. Postprandial blood glucose and insulin levels were measured on days 1 and 5 (baseline 0, post-meal 30, 60, 90, and 120 min). Differences in iAUC, Cmax, and Tmax were determined between the placebo and GLUBLOCTM-treated cohorts.

RESULTS

Significant changes in total iAUC (0-120 min), Cmax, and Tmax of postprandial blood glucose and insulin levels were noticed upon GLUBLOCTM supplementation. The percentage reduction in the iAUC of blood glucose levels was 49.78% (iAUC0-60min) and 43.36% (iAUC0-120min), respectively, compared with the placebo in the sucrose drink intake study. Similarly, there was a 41.13% (iAUC0-60min) and 20.26% (iAUC0-120min) glucose-lowering effect compared with the placebo in the carbohydrate-rich meal intake study.

CONCLUSIONS

Premeal supplementation with GLUBLOCTM significantly reduced the postprandial surge in blood glucose and insulin levels after a carbohydrate-rich meal or sucrose drink intake over 120 min in healthy individuals. This study proves that GLUBLOCTM can manage steady postprandial blood glucose levels.

Rhodiosin from Rhodiola crenulata effectively alleviate postprandial hyperglycemia by inhibiting both the activity and production of α‑glucosidase

BACKGROUND

Effective control of postprandial blood glucose (PBG) level is essential for the prevention and treatment of diabetes and its complications. Several flavonoids have attracted much attention due to their significant PBG-lowering effects. However, there is still a certain gap in the in vivo hypoglycemic activity of most flavonoids compared to first-line drugs available on the market, and are still lack of the PBG-lowering effects of 8-hydroxyflavones and their structure-activity relationship.

PURPOSE

Evaluate hypoglycemic effects of 8-hydroxyflavones from Rhodiola crenulata in vitro and in vivo, especially comparatively analyze the relationship between hypoglycemic effects and flavonoid configuration and reveal the possible mechanism of 8-hydroxyflavones in lowering hyperglycemia.

METHODS

Starch, maltose, sucrose, and glucose tolerance tests in both diabetic and normal mice were used to evaluate and compare the hypoglycemic effects of 8-hydroxyflavones rhodiosin (RHS), rhodionin (RHN), and herbacetin (HBT). Molecular docking, enzyme kinetics, and immunofluorescence analysis were used to research the possible hypoglycemic mechanisms of 8-hydroxyflavones.

RESULTS

RHS (5 and 10 mg/kg) could efficiently decrease PBG levels in both normal and diabetes mice. Moreover, RHS, RHN, and HBT all had significant PBG-lowering effects in transgenic diabetes mice, and the effects were equivalent to or stronger than acarbose. Further mechanism research indicated that 8-hydroxyflavones achieved PBG-lowering effects by inhibiting both the activity and production of glycosidase. Notably, we have innovatively discovered that inhibiting the expression of glycosidases rather than just their activities may be a new target for hypoglycemic drugs.

CONCLUSION

We have firstly comprehensively and systematically clarified PBG-lowering effects of 8-hydroxyflavones from Rhodiola crenulata, and revealed their structure-activity relationships and hypoglycemic mechanisms. The study demonstrated that the substitution of 8-hydroxy groups in flavonoids could significantly enhance their hypoglycemic effects, which were equivalent to or stronger than commercially available drug acarbose. 8-Hydroxyflavones could be used as therapeutic or health drugs with significant potential to reduce postprandial hyperglycemia.

A randomized double blind placebo controlled trial to assess the safety and efficacy of a patented fenugreek (Trigonella foenum-graecum) seed extract in Type 2 diabetics

Background

Fenugreek plant (Trigonella foenum-graecum) constitutes a traditionally acclaimed herbal remedy for many human ailments including diabetes, obesity, neurodegenerative diseases, and reproductive disorders. It is also used as an effective anti-oxidative, anti-inflammatory, antibacterial, and anti-fungal agent. The seed of the plant is especially enriched in several bioactive molecules including polyphenols, saponins, alkaloids, and flavonoids and has demonstrated potential to act as an antidiabetic phytotherapeutic. A novel patented formulation (Fenfuro®) was developed in our laboratory from the fenugreek seeds which contained >45% furostanolic saponins (HPLC).

Objective

A placebo-controlled clinical compliance study was designed to assess the effects of complementing Fenfuro® on a randomized group of human volunteers on antidiabetic therapy (Metformin and sulphonylurea) in controlling the glycemic index along with simultaneous safety assessment.

Study methodology and trial design

In a randomized double-blind, placebo-controlled trial, 42 individuals (21 male and 21 female volunteers) in the treatment group (out of 57 enrolled) and 39 individuals (17 male and 22 female volunteers) in the placebo group (out of 47 enrolled), all on antidiabetic therapy with Metformin/Metformin with sulphonyl urea within the age group of 18-65 years were administered either 1,000 mg (500 mg × 2) (Fenfuro®) capsules or placebo over a period of 12 consecutive weeks. Fasting and postprandial glucose along with glycated hemoglobin were determined as primary outcomes to assess the antidiabetic potential of the formulation. Moreover, in order to evaluate the safety of the formulation, C-peptide and Thyroid Stimulating Hormone (TSH) levels as well as immunohematological parameters were assessed between the treatment and placebo groups at the completion of the study.

Results

After 12 weeks of administration, both fasting as well as postprandial serum glucose levels decreased by 38 and 44% respectively in the treatment group. Simultaneously, a significant reduction in glycated hemoglobin by about 34.7% was also noted. The formulation did not have any adverse effect on the study subjects as there was no significant change in C- peptide level and TSH level; liver, kidney, and cardiovascular function was also found to be normal as assessed by serum levels of key immunohematological parameters. No adverse events were reported.

Conclusion

This clinical compliance study re-instated and established the safety and efficacy of Fenfuro® as an effective phytotherapeutic to treat hyperglycemia.

Review of the pharmacological properties of marine macroalgae used in the treatment of diabetes mellitus in Indonesia

Indonesia is the largest archipelagic country in the world, with 70% of its territory covered by oceans that are rich in various types of biological resources. Indonesia's biodiversity has made it possible to develop natural medicine. Marine algae have enormous potential, but the types of marine algae used still need to be more varied. Research on the pharmacology of marine macroalgae has been conducted in Indonesia, but studies on such topic related to diabetes mellitus (DM) still need to be completed. This study provides a comprehensive dataset of pharmacological anti-diabetic potential of marine macroalgae used for managing DM and reports on preclinical trials that provide pharmacological evidence. Data on the Indonesian marine macroalgae used to lower blood glucose were obtained from online sources. The bioactive chemicals of marine macroalgae have been found efficient at blocking several diabetes enzymes in in-vivo and in-vitro studies, and such chemicals have anti-inflammatory, anti-obesity, antioxidant, and other therapeutic benefits. The Google Scholar was used to search for the pharmacological literature with the keywords marine AND macroalgae AND diabetes AND Indonesia. Pharmacological research on the anti-diabetic activity of marine macroalgae has been carried out on five major Indonesian islands, including Sumatra, Kalimantan, Java, Sulawesi, and Papua, which encompassed 12 provinces: Southwest Papua, South Sulawesi, West Kalimantan, Riau Archipelago, Banten, West Java, North Sulawesi, East Java, Yogyakarta, Maluku, Jakarta, and Bengkulu. Articles on preclinical tests (in vitro and in vivo) were also used for the phytochemical problem section. The results briefly describe which class of algae has been widely used in Indonesia as an anti-diabetic. The findings of this research can be utilized to help find DM treatment drugs based on natural resources from marine macroalgae.

In Vitro Analysis of Camellia sinensis Leaf Extract Against Diabetes Mellitus

INTRODUCTION

Diabetes mellitus (DM) poses a significant global health challenge, with its prevalence steadily increasing. Natural compounds derived from plants have garnered attention for their potential therapeutic effects in managing this metabolic disorder. Camellia sinensis, commonly known as tea, is rich in bioactive compounds exhibiting various pharmacological properties. This study investigates the potential anti-diabetic activity of C. sinensis leaf extract through in vitro analysis.

MATERIALS AND METHODS

Camella sinensis leaf extract was prepared by grinding the plant's leaf into a powder, mixing it with distilled water, and heating. The antidiabetic activity was assessed through α-Amylase and α-Glucosidase inhibitory assays, employing varying concentrations of the plant extract. Molecular docking analysis utilized Autodock 1.5.6 software (The Scripps Research Institute, California, US) to predict ligand-receptor interactions, guiding subsequent experimental validation.

RESULT

Camella sinensis leaf extract exhibited high phenolic content, suggesting potential in managing hyperglycemia. Tannins may aid glucose absorption and inhibit adipogenesis, making them promising for non-insulin-dependent DM (NIDDM). Terpenoids, with antioxidant activity, inhibit advanced glycation. Saponins and steroids were absent. Molecular docking revealed residues like IR, IRS1, and AS160 with significant impact on α-Amylase and α-Glucosidase, comparable to metformin.

CONCLUSION

The findings of this study highlight the promising potential of C. sinensis leaf extract in managing hyperglycemia associated with DM. The high phenolic content aids in glucose regulation. Specifically, the presence of tannins suggests a potential role in modulating glucose absorption and inhibiting adipogenesis, which could be particularly beneficial for individuals with NIDDM. These findings provide valuable insights into the molecular mechanisms underlying the potential therapeutic efficacy of C. sinensis leaf extract against DM, paving the way for further research and development of novel therapeutic interventions in diabetes management.

Novel Functional Food Properties of Forest Onion (Eleutherine bulbosa Merr.) Phytochemicals for Treating Metabolic Syndrome: New Insights from a Combined Computational and In Vitro Approach

Metabolic syndrome is a global health problem. The use of functional foods as dietary components has been increasing. One food of interest is forest onion extract (FOE). This study aimed to investigate the effect of FOE on lipid and glucose metabolism in silico and in vitro using the 3T3-L1 mouse cell line. This was a comprehensive study that used a multi-modal computational network pharmacology analysis and molecular docking in silico and 3T3-L1 mouse cells in vitro. The phytochemical components of FOE were analyzed using untargeted ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS). Next, an in silico analysis was performed to determine FOE's bioactive compounds, and a toxicity analysis, protein target identification, network pharmacology, and molecular docking were carried out. FOE's effect on pancreatic lipase, α-glucosidase, and α-amylase inhibition was determined. Finally, we determined its effect on lipid accumulation and MAPK8, PPARG, HMGCR, CPT-1, and GLP1 expression in the preadipocyte 3T3-L1 mouse cell line. We showed that the potential metabolites targeted glucose and lipid metabolism in silico and that FOE inhibited pancreatic lipase levels, α-glucosidase, and α-amylase in vitro. Furthermore, FOE significantly (p < 0.05) inhibits targeted protein expressions of MAPK8, PPARG, HMGCR, CPT-1, and GLP-1 in vitro in 3T3-L1 mouse cells in a dose-dependent manner. FOE contains several metabolites that reduce pancreatic lipase levels, α-glucosidase, α-amylase, and targeted proteins associated with lipid and glucose metabolism in vitro.

Potential antioxidant, α-glucosidase, butyrylcholinesterase and acetylcholinesterase inhibitory activities of major constituents isolated from Alpinia officinarum hance rhizomes: computational studies and in vitro validation

Alpinia officinarum is a commonly used spice with proven folk uses in various traditional medicines. In the current study, six compounds were isolated from its rhizomes, compounds 1-3 were identified as diarylheptanoids, while 4-6 were identified as flavonoids and phenolic acids. The isolated compounds were subjected to virtual screening against α-glucosidase, butyrylcholinesterase (BChE), and acetylcholinesterase (AChE) enzymes to evaluate their potential antidiabetic and anti-Alzheimer's activities. Molecular docking and dynamics studies revealed that 3 exhibited a strong binding affinity to human a α- glucosidase crystal structure compared to acarbose. Furthermore, 2 and 5 demonstrated high potency against AChE. The virtual screening results were further supported by in vitro assays, which assessed the compounds' effects on α-glucosidase, cholinesterases, and their antioxidant activities. 5-Hydroxy-7-(4-hydroxy-3-methoxyphenyl)-1-phenylheptan-3-one (2) showed potent antioxidant effect in both ABTs and ORAC assays, while p-hydroxy cinnamic acid (6) was the most potent in the ORAC assay. In contrary, kaempferide (4) and galangin (5) showed the most potent effect in metal chelation assay. 5-Hydroxy-1,7-diphenylhepta-4,6-dien-3-one (3) and 6 revealed the most potent effect as α-glucosidase inhibitors where compound 3 showed more potent effect compared to acarbose. Galangin (5) revealed a higher selectivity to BChE, while 2 showed the most potent activity to (AChE).

Seaweeds as Nutraceutical Elements and Drugs for Diabetes Mellitus: Future Perspectives

Diabetes mellitus is a chronic metabolic condition marked by high blood glucose levels caused by inadequate insulin synthesis or poor insulin use. This condition affects millions of individuals worldwide and is linked to a variety of consequences, including cardiovascular disease, neuropathy, nephropathy, and retinopathy. Diabetes therapy now focuses on controlling blood glucose levels through lifestyle changes, oral medicines, and insulin injections. However, these therapies have limits and may not successfully prevent or treat diabetic problems. Several marine-derived chemicals have previously demonstrated promising findings as possible antidiabetic medicines in preclinical investigations. Peptides, polyphenols, and polysaccharides extracted from seaweeds, sponges, and other marine species are among them. As a result, marine natural products have the potential to be a rich source of innovative multitargeted medications for diabetes prevention and treatment, as well as associated complications. Future research should focus on the chemical variety of marine creatures as well as the mechanisms of action of marine-derived chemicals in order to find new antidiabetic medicines and maximize their therapeutic potential. Based on preclinical investigations, this review focuses on the next step for seaweed applications as potential multitargeted medicines for diabetes, highlighting the bioactivities of seaweeds in the prevention and treatment of this illness.

Synthesis and Biological Evaluation of New Dihydrofuro[3,2-b]piperidine Derivatives as Potent α-Glucosidase Inhibitors

Inhibition of glycoside hydrolases has widespread application in the treatment of diabetes. Based on our previous findings, a series of dihydrofuro[3,2-b]piperidine derivatives was designed and synthesized from D- and L-arabinose. Compounds 32 (IC50 = 0.07 μM) and 28 (IC50 = 0.5 μM) showed significantly stronger inhibitory potency against α-glucosidase than positive control acarbose. The study of the structure-activity relationship of these compounds provides a new clue for the development of new α-glucosidase inhibitors.

Butyrate's (a short-chain fatty acid) microbial synthesis, absorption, and preventive roles against colorectal and lung cancer

Butyrate, a short-chain fatty acid (SCFA) produced by bacterial fermentation of fiber in the colon, is a source of energy for colonocytes. Butyrate is essential for improving gastrointestinal (GI) health since it helps colonocyte function, reduces inflammation, preserves the gut barrier, and fosters a balanced microbiome. Human colonic butyrate producers are Gram-positive firmicutes, which are phylogenetically varied. The two most prevalent subgroups are associated with Eubacterium rectale/Roseburia spp. and Faecalibacterium prausnitzii. Now, the mechanism for the production of butyrate from microbes is a very vital topic to know. In the present study, we discuss the genes encoding the core of the butyrate synthesis pathway and also discuss the butyryl-CoA:acetate CoA-transferase, instead of butyrate kinase, which usually appears to be the enzyme that completes the process. Recently, butyrate-producing microbes have been genetically modified by researchers to increase butyrate synthesis from microbes. The activity of butyrate as a histone deacetylase inhibitor (HDACi) has led to several clinical trials to assess its effectiveness as a potential cancer treatment. Among various significant roles, butyrate is the main energy source for intestinal epithelial cells, which helps maintain colonic homeostasis. Moreover, people with non-small-cell lung cancer (NSCLC) have distinct gut microbiota from healthy adults and frequently have dysbiosis of the butyrate-producing bacteria in their guts. So, with an emphasis on colon and lung cancer, this review also discusses how the microbiome is crucial in preventing the progression of certain cancers through butyrate production. Further studies should be performed to investigate the underlying mechanisms of how these specific butyrate-producing bacteria can control both colon and lung cancer progression and prognosis.

Carbonylbis(hydrazine-1-carbothioamide) derivatives as a new class of α-glucosidase inhibitors and their mechanistic insights via molecular docking and dynamic simulations

In the past, efforts have been made to find a cure for diabetes, mainly evaluating new classes of compounds to explore their potency. In this study, we present the synthesis and evaluation of carbonylbis(hydrazine-1-carbothioamide) derivatives as potential α-glucosidase inhibitors, employing both in vivo and in silico investigations. The in vitro experiments revealed that all tested compounds were significantly potent for α-glucosidase inhibition, with the lead compound 3a displaying approximately 80 times higher activity than acarbose. To delve deeper, in silico induced fit docking, pharmacokinetics, and molecular dynamics studies were conducted. Significantly, compound 3a exhibited a docking score of -7.87 kcal/mol, surpassing acarbose, which had a docking score of -6.59 kcal/mol. The in silico ADMET indicated that most of the synthesized compounds have properties conducive to drug development. Molecular dynamics analysis demonstrated that, when the ligand 3a was coupled with the target 3TOP, Cα-RMSD backbone RMSD values below 2.4 Å and "Lig_fit_Prot" values below 2.7 Å were observed. QSAR analysis demonstrates that the "fOC8A" descriptor positively correlates with α-glucosidase inhibition activity, while "lipoplus_AbSA" positively contributes and "notringC_notringO_8B" negatively contributes to this activity.

Albadri A, Patel H, Kadri A, Aouadi K. Identification of dual-target isoxazolidine-isatin hybrids with antidiabetic potential: Design, synthesis, in vitro and multiscale molecular modeling approaches

In the development of novel antidiabetic agents, a novel series of isoxazolidine-isatin hybrids were designed, synthesized, and evaluated as dual α-amylase and α-glucosidase inhibitors. The precise structures of the synthesized scaffolds were characterized using different spectroscopic techniques and elemental analysis. The obtained results were compared to those of the reference drug, acarbose (IC50 = 296.6 ± 0.825 μM for α-amylase & IC50 = 780.4 ± 0.346 μM for α-glucosidase). Among the title compounds, 5d exhibited impressive α-amylase and α-glucosidase inhibitory activity with IC50 values of 30.39 ± 1.52 μM and 65.1 ± 3.11 μM, respectively, followed by 5h (IC50 = 46.65 ± 2.3 μM; IC50 = 85.16 ± 4.25 μM) and 5f (IC50 = 55.71 ± 2.78 μM; IC50 = 106.77 ± 5.31 μM). Mechanistic studies revealed that the most potent derivative 5d bearing the chloro substituent attached to the oxoindolin-3-ylidene core, and acarbose, are a competitive inhibitors of α-amylase and α-glucosidase, respectively. Structure activity relationship (SAR) was examined to guide further structural optimization of the most appropriate substituent(s). Moreover, drug-likeness qualities and ADMET prediction of the most active analogue, 5d was also performed. Subsequently, 5d was subjected to molecular docking and dynamic simulation during the progression of 120 ns analysis to check the essential ligand-receptor patterns, and to estimate its stability. In silico studies were found in good agreement with the in vitro enzymatic inhibitions results. In conclusion, we demonstrated that most potent compound 5d could be exploited as dual potential inhibitor of α-amylase and α-glucosidase for possible management of diabetes.

Identification of isobenzofuranone derivatives as promising antidiabetic agents: Synthesis, in vitro and in vivo inhibition of α-glucosidase and α-amylase, computational docking analysis and molecular dynamics simulations

Diabetes mellitus, one of the major health challenges of the 21st century, is associated with numerous biomedical complications including retinopathy, neuropathy, nephropathy, cardiovascular diseases and liver disorders. To control the chronic hyperglycemic condition, the development of potential inhibitors of drug targets such as α-glucosidase and α-amylase remains a promising strategy and focus of continuous efforts. Therefore, in the present work, a concise library of isobenzofuranone derivatives (3a-q) was designed and synthesized using Suzuki-Miyaura cross-coupling approach. The biological potential of these heterocyclic compounds against carbohydrate-hydrolyzing enzymes; α-glucosidase and α-amylase, was examined. In vitro inhibitory results demonstrated that the tested isobenzofuranones were considerably more effective and potent inhibitors than the standard drug, acarbose. Compound 3d having an IC50 value of 6.82 ± 0.02 μM was emerged as the lead candidate against α-glucosidase with ⁓127-folds strong inhibition than acarbose. Similarly, compound 3g demonstrated ⁓11-folds higher inhibition strength against α-amylase when compared with acarbose. Both compounds were tested in vivo and results demonstrate that the treatment of diabetic rats with α-amylase inhibitor show more pronounced histopathological normalization in kidney and liver than with α-glucosidase inhibitor. The Lineweaver-Burk plot revealed an uncompetitive mode of inhibition for 3d against α-glucosidase whereas compound 3g exhibited mixed inhibition against α-amylase. Furthermore, in silico molecular docking and dynamics simulations validated the in vitro data for these compounds whereas pharmacokinetics profile revealed the druglike properties of potent inhibitors.

In silico exploration of the potential inhibitory activities of in-house and ZINC database lead compounds against alpha-glucosidase using structure-based virtual screening and molecular dynamics simulation approach

Inhibitors of α-glucosidase have been used to treat type-2 diabetes (T2DM) by preventing the breakdown of carbohydrates into glucose and prevent enhancing glucose conversion. Structure-based virtual screening (SBVS) was used to generate novel chemical scaffold-ligand α-glucosidase inhibitors. The databases were screened against the receptor α-glucosidase using SBVS and molecular dynamics simulation (MDS) techniques in this study. Based on molecular docking studies, three and two compounds of α-glucosidase inhibitors were chosen from a commercial database (ZINC) and an In-house database for this study respectively. The mode of binding interactions of the selected compounds later predicted their α-glucosidase inhibitory potential. Finally, one out of three lead compound from ZINC and one out of two lead compound from In-house database were shortlisted based on interactions. Furthermore, MDS and post-MDS strategies were used to refine and validate the shortlisted leads along with the reference acarbose/α-glucosidase. The Hits' ability to inhibit α-glucosidase was predicted by SBVS, indicating that these compounds have good inhibitory activities. The lead inhibitor's structure may serve as templates for the design of novel inhibitors, and in vitro testing to confirm their anti-diabetic potential is necessary. These insights can help rationally design new effective anti-diabetic drugs.Communicated by Ramaswamy H. Sarma.

An analytical framework combining online high-performance liquid chromatography methodologies and biological properties of different extracts of Leonurus cardiaca

Little or no information is available concerning online high-performance liquid chromatography (HPLC) antioxidants and the antibiofilm effect of Leonurus cardiaca. Five distinct extractions of methanolic, ethyl acetate, dichloromethane, hexane, and water were obtained from L. cardiaca. In the online-HPLC-antioxidant analysis of all examined samples, rosmarinic acid emerged as the primary antioxidant, registering concentrations ranging from 6 to 15 ppm at wavelengths of 517 and 734 nm. Notably, the water extract exhibited robust antioxidant activity In vitro. Regarding acetylcholinesterase and butrylcholinesterase inhibition, the n-hexane extract exhibited superior inhibition with values of 3.08 and 5.83 galanthamine equivalent, respectively. Except for the water extract, all tested extracts (at a concentration of 20 μg/mL) exhibited substantial inhibitory activity against biofilm formation, in many cases superior to 80%, and reached even 94.52% against Escherichia coli. Although less vigorous, the extracts also acted against the mature biofilm (inhibition up 76.50% against Staphylococcus aureus). They could work against the metabolism inside an immature and mature biofilm, with inhibition percentages up to 93.18% (vs. Pseudomonas aeruginosa) and 76.50% (vs. Acinetobacter baumannii), respectively. Considering its significant antioxidants, enzyme inhibition, and antimicrobial activity, L. cardiaca emerges as a promising candidate for therapeutic potential.

α-Glucosidase inhibition by green, white and oolong teas: in vitro activity and computational studies

Natural α-glucosidase inhibitors from plant-based foods such as catechins offer an attractive strategy for their potential anti-diabetic effects. In this study, infusions of three different tea types (green, white, and oolong) were investigated for their total phenolic (TPC) and catechins (EGCG, ECG, EGC, and EC) content, and for their α-glucosidase inhibitory activities. We observed that the level of TPC in white tea was significantly higher compared to oolong and green tea, which suggests higher content of EGCG and ECG catechins in fresh young leaves. Our findings showed that the higher content of such catechins in the infusion of white tea well correlated with a strong inhibition of α-glucosidase, and such inhibition was demonstrated to be more effective than the FDA-approved drug acarbose. Then, we computationally explored the molecular requirements for enzyme inhibition, especially for the most active catechins EGCG and ECG, as well as their disposition/stability within the active site.

Natural Inhibitors of Mammalian α-Amylases as Promising Drugs for the Treatment of Metabolic Diseases

α-Amylase is a generally acknowledged molecular target of a distinct class of antidiabetic drugs named α-glucosidase inhibitors. This class of medications is scarce and rather underutilized, and treatment with current commercial drugs is accompanied by unpleasant adverse effects. However, mammalian α-amylase inhibitors are abundant in nature and form an extensive pool of high-affinity ligands that are available for drug discovery. Individual compounds and natural extracts and preparations are promising therapeutic agents for conditions associated with impaired starch metabolism, e.g., diabetes mellitus, obesity, and other metabolic disorders. This review focuses on the structural diversity and action mechanisms of active natural products with inhibitory activity toward mammalian α-amylases, and emphasizes proteinaceous inhibitors as more effective compounds with significant potential for clinical use.

In Vitro and In Vivo Evaluation for Antioxidant and Anti-Diabetic Properties of Cyperus rotundus L. Kombucha

Cyperus rotundus L. exhibits promising potential for the development of functional foods due to its documented pharmacological and biological activities. This study investigated the antioxidant and anti-diabetic properties of C. rotundus kombucha. The results demonstrated potent antioxidant activity with an IC50 value of 76.7 ± 9.6 µL/mL for the DPPH assay and 314.2 ± 16.9 µL/mL for the ABTS assay. Additionally, the kombucha demonstrated alpha-glucosidase inhibitory with an IC50 value of 142.7 ± 5.2 µL/mL. This in vitro antioxidant potential was further validated in vivo using Drosophila. Drosophila fed a high-sugar diet and supplemented with pure kombucha revealed significant increases in DPPH and ABTS free radical scavenging activity. Drosophila on a high-sugar diet supplemented with varying kombucha concentrations manifested enhanced resistance to oxidative stresses induced by H2O2 and paraquat. Concurrently, there was a notable decline in lipid peroxidation levels. Additionally, significant upregulations in CAT, SOD1, and SOD2 activities were observed when the high-sugar diet was supplemented with kombucha. Furthermore, in vivo assessments using Drosophila demonstrated significant reductions in alpha-glucosidase activity when fed with kombucha (reduced by 34.04%, 13.79%, and 11.60% when treated with 100%, 40%, and 10% kombucha, respectively). A comprehensive GC-MS and HPLC analysis of C. rotundus kombucha detected the presence of antioxidative and anti-glucosidase compounds. In conclusion, C. rotundus kombucha exhibits considerable antioxidant and anti-diabetic properties, demonstrating its potential as a beneficial beverage for health promotion.

Phytochemical characterization of Typha domingensis and the assessment of therapeutic potential using in vitro and in vivo biological activities and in silico studies

Typha domingensis, a medicinal plant with significant traditional importance for curing various human diseases, has potentially bioactive compounds but was less explored previously. Therefore, this study aims to investigate the therapeutic potential of T. domingensis by evaluating the phytochemical profile through high-performance liquid chromatography (HPLC) techniques and its biological activities (in vitro and in vivo) from the methanolic extract derived from the entire plant (TDME). The secondary metabolite profile of TDME regulated by reverse phase ultra-high-performance liquid chromatography-mass spectrometry (RP-UHPLC-MS) revealed some bioactive compounds by -ve and +ve modes of ionization. The HPLC quantification study showed the precise quantity of polyphenols (p-coumaric acid, 207.47; gallic acid, 96.25; and kaempferol, 95.78 μg/g extract). The enzyme inhibition assays revealed the IC50 of TDME as 44.75 ± 0.51, 52.71 ± 0.01, and 67.19 ± 0.68 µgmL-1, which were significant compared to their respective standards (indomethacin, 18.03 ± 0.12; quercetin, 4.11 ± 0.01; and thiourea, 8.97 ± 0.11) for lipoxygenase, α-glucosidase, and urease, respectively. Safety was assessed by in vitro hemolysis (4.25% ± 0.16% compared to triton × 100, 93.51% ± 0.36%), which was further confirmed (up to 10 g/kg) by an in vivo model of rats. TDME demonstrated significant (p < 0.05) potential in analgesic activity by hot plate and tail immersion tests and anti-inflammatory activity by the carrageenan-induced hind paw edema model. Pain latency decreased significantly, and the anti-inflammatory effect increased in a dose-dependent way. Additionally, in silico molecular docking revealed that 1,3,4,5-tetracaffeoylquinic acid and formononetin 7-O-glucoside-6″-O-malonate possibly contribute to enzyme inhibitory activities due to their higher binding affinities compared to standard inhibitors. An in silico absorption, distribution, metabolism, excretion, and toxicological study also predicted the pharmacokinetics and safety of the chosen compounds identified from TDME. To sum up, it was shown that TDME contains bioactive chemicals and has strong biological activities. The current investigations on T. domingensis could be extended to explore its potential applications in nutraceutical industries and encourage the isolation of novel molecules with anti-inflammatory and analgesic effects.

Antioxidant and α-glucosidase inhibitory activities of compound isolated from Stachytarpheta jamaicensis (L) Vahl. leaves

Stachytarpheta jamaicensis is one of the folk medicines used for the treatment of diabetes in Ambon, Indonesia, but there are limited studies on the bioactivities of its constituents. This study aims to assess the antioxidant and antidiabetic activities of four extracts of S. jamaicensis leaves extracted using several solvents. Bioassay guided fractionation on each extract establishes for exploring S. jamaicensis leaves active compounds. The antioxidant was evaluated using the DPPH and ABTS methods, while the α-glucosidase inhibitory was carried out in vitro assay. The results showed that the methanol extract of S. jamaicensis leaves displays inhibition of DPPH, ABTS and α-glucosidase activity compared to other solvent extracts. Furthermore, 6β-hydroxyipolamiide was successfully isolated from the methanol extract of S. jamicensis leaves which was reported to have α-glucosidase inhibitory activity with an IC50 of 539.17 μg/mL. Based on the results, S. jamaicensis could be recommended as an antioxidant and antidiabetic agent.

Assessment of the Chemical Profile and Potential Medical Effects of a Flavonoid-Rich Extract of Eclipta prostrata L. Collected in the Central Highlands of Vietnam

Eclipta prostrata L. (EPL), a medicinal plant, is widely utilized in the central highlands of Vietnam. This study aims to assess the chemical profile and potential medical effects of an EPL extract rich in flavonoids. A total of 36 secondary metabolites were identified from the EPL extract through GC-MS and UHPLC-UV analysis. Among them, 15 volatile compounds and several phenolic and flavonoid chemicals, including salicylic acid, epicatechin gallate, isovitexin, and apigetrin, were reported in EPL extract for the first time. This herbal extract demonstrated moderate inhibition against α-amylase and α-glucosidase, and high anti-oxidant and anti-acetylcholinesterase activities (IC50 = 76.8 ± 0.8 μg/mL). These promising attributes can be likely attributed to the high levels of major compounds, including wedelolactone (1), chlorogenic acid (3), epicatechin gallate (6), salicylic acid (8), isovitexin (9), apigetrin (11), and myricetin (12). These findings align with the traditional use of EPL for enhancing memory and cognitive function, as well as its potential benefits in diabetes management. The results of the molecular docking study reveal that the major identified compounds (1, 6, 9, and 11) showed a more effective acetylcholinesterase inhibitory effect than berberine chloride, with good binding energy (DS values, -12.3 to -14.3 kcal/mol) and acceptable values of RMSD (1.02-1.67 Å). Additionally, almost all the identified major compounds exhibited good ADMET properties within the required limits.

Anti-Hyperglycemic Effects of Bioactive Compounds in the Context of the Prevention of Diet-Related Diseases

Diet-related diseases are health conditions primary caused by poor nutrition. These diseases encompass obesity, type 2 diabetes, cardiovascular diseases, osteoporosis, and certain types of cancer. Functional foods and nutraceuticals offer a promising dietary approach to addressing diet-related diseases across various clinical contexts. The bioactive compounds found in these foods are the subject of intensive studies aimed at discovering their anti-hyperglycemic effects, which are beneficial in alleviating chronic diseases and protecting human health. Hyperglycemia is a common risk factor for metabolic disease and mortality worldwide. Chronic hyperglycemic states can lead to many long-term complications, such as retinopathy, neuropathy, kidney disease, heart disease, cancer, and diabetes. This review explores the potential anti-hyperglycemic effects of bioactive compounds, specifically flavonoids and phenolic acids, and their proposed roles in mitigating chronic diseases and promoting human health. By thoroughly examining the existing literature, we investigated the potential anti-hyperglycemic effects of these bioactive compounds and their proposed roles in managing chronic diseases. The goal of this paper was to enhance our comprehension of how these compounds modulate glucose transporters, with the ultimate aim of identifying effective strategies for the prevention and treatment of diet-related diseases. Overall, this review investigated the use of bioactive compounds from functional foods as potential inhibitors of glucose transporters in the context of prevention/treatment of diet-related diseases.

Synthesis and diverse biological activities of substituted indole β-carbolines: a review

β-Carboline bearing indole is one of the heterocyclic compounds that play a vital role in medicinal chemistry with various pharmacological effects such as anticancer, anti-acetylcholinesterase, anti-inflammation, antimalarial, antibacterial, anti-diabetic, and antioxidant. Over the last two decades, many studies on the synthesis and biological activity of indole β-carboline compounds have been conducted yet there is no appropriate data summary has been presented. Thus, the goal of this review was to highlight the synthesis pathway and bioactivity of substituted indole β-carboline reported from 2005 to date. In addition, this will encourage further investigation into the synthesis and evaluation of new indole β-carboline, in the hope of contributing to the development of potentially new medications for the treatment of various ailments.

Exploring plant-based alpha-glucosidase inhibitors: promising contenders for combatting type-2 diabetes

Objective: This systematic review aimed to provide comprehensive details on the α-G inhibitory potential of various bioactive compounds derived from natural sources.Methods: A comprehensive literature search was conducted using various databases and search engines, including Science Direct, Google Scholar, SciFinder, Web of Science, and PubMed until May, 2023.Results and conclusions: The enzyme alpha-glucosidase (α-G) is found in the brush border epithelium of the small intestine and consists of duplicated glycoside hydrolase (GH31) domain. It involves the conversion of disaccharides and oligosaccharides into monosaccharides by acting on alpha (1 → 4) and (1 → 6) linked glucose residue. Once absorbed, glucose enters the bloodstream and elevates postprandial glucose, which is associated with the development of type 2 Diabetes (T2D). Epidemic obesity, cardiovascular disease, and nephropathy are linked to T2D. Traditional medicinal plants with α-G inhibitory potential are commonly used to treat T2D due to the adverse effects of currently used α-G inhibitors miglitol, acarbose, and voglibose. Various bioactive compounds derived from natural sources, including lupenone, Wilforlide A, Baicalein, Betulinic acid, Ursolic acid, Oleanolic acid, Katononic acid, Carnosol, Hypericin, Astilbin, lupeol, betulonic acid, Fagomine, Lactucaxanthin, Erythritol, GP90-1B, Procyanidins, Galangin, and vomifoliol retain α-G inhibitory potential for regulating hyperglycaemia.

Metabolomics Analysis and Biochemical Profiling of Arsenic-Induced Metabolic Impairment and Disease Susceptibility

Our study aimed to conduct a comprehensive biochemical profiling and metabolomics analysis to investigate the effects of arsenic-induced metabolic disorders, with a specific focus on disruptions in lipid metabolism, amino acid metabolism, and carbohydrate metabolism. Additionally, we sought to assess the therapeutic potential of resveratrol (RSV) as a remedy for arsenic-induced diabetes, using metformin (MF) as a standard drug for comparison. We measured the total arsenic content in mouse serum by employing inductively coupled plasma mass spectrometry (ICP-MS) after administering a 50-ppm solution of sodium arsenate (50 mg/L) in purified water. Our findings revealed a substantial increase in total arsenic content in the exposed group, with a mean value of 166.80 ± 8.52 ppb (p < 0.05). Furthermore, we investigated the impact of arsenic exposure on various biomarkers using enzyme-linked immunosorbent assay (ELISA) methods. Arsenic exposed mice exhibited significant hyperglycemia (p < 0.001) and elevated levels of homeostatic model assessment of insulin resistance (HOMA-IR), hemoglobin A1c (Hb1Ac), Inflammatory biomarkers as well as liver and kidney function biomarkers (p < 0.05). Additionally, the levels of crucial enzymes linked to carbohydrate metabolism, including α-glucosidase, hexokinase, and glucose-6-phosphatase (G6PS), and oxidative stress biomarkers, such as levels of glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GPx), catalase, and superoxide dismutase (SOD), were significantly reduced in the arsenic-exposed group compared to the control group (p < 0.05). However, the level of MDA was significantly increased. Molecular analysis of gene expression indicated significant upregulation of key enzymes involved in lipid metabolism, such as carnitine palmitoyl-transferase-I (CPT-I), carnitine palmitoyl-transferase-II (CPT-II), lecithin-cholesterol acyltransferase (LCAT), and others. Additionally, alterations in gene expression related to glucose transporter-2 (GLUT-2), glucose-6-phosphatase (G6PC), and glucokinase (GK), associated with carbohydrate metabolism, were observed. Amino acid analysis revealed significant decreases in nine amino acids in arsenic-exposed mice. Metabolomics analysis identified disruptions in lipid metabolomes, amino acids, and arsenic metabolites, highlighting their involvement in essential metabolic pathways. Histopathological observations revealed significant changes in liver architecture, hepatocyte degeneration, and increased Kupffer cells in the livers of arsenic-exposed mice. In conclusion, these findings enhance our comprehension of the impact of environmental toxins on metabolic health and offer potential avenues for remedies against such disruptions.

Algae-Derived Natural Products in Diabetes and Its Complications-Current Advances and Future Prospects

Diabetes poses a significant global health challenge, necessitating innovative therapeutic strategies. Natural products and their derivatives have emerged as promising candidates for diabetes management due to their diverse compositions and pharmacological effects. Algae, in particular, have garnered attention for their potential as a source of bioactive compounds with anti-diabetic properties. This review offers a comprehensive overview of algae-derived natural products for diabetes management, highlighting recent developments and future prospects. It underscores the pivotal role of natural products in diabetes care and delves into the diversity of algae, their bioactive constituents, and underlying mechanisms of efficacy. Noteworthy algal derivatives with substantial potential are briefly elucidated, along with their specific contributions to addressing distinct aspects of diabetes. The challenges and limitations inherent in utilizing algae for therapeutic interventions are examined, accompanied by strategic recommendations for optimizing their effectiveness. By addressing these considerations, this review aims to chart a course for future research in refining algae-based approaches. Leveraging the multifaceted pharmacological activities and chemical components of algae holds significant promise in the pursuit of novel antidiabetic treatments. Through continued research and the fine-tuning of algae-based interventions, the global diabetes burden could be mitigated, ultimately leading to enhanced patient outcomes.

New Insights into the Latest Advancement in α-Amylase Inhibitors of Plant Origin with Anti-Diabetic Effects

The rising predominance of type 2 diabetes, combined with the poor medical effects seen with commercially available anti-diabetic medications, has motivated the development of innovative treatment approaches for regulating postprandial glucose levels. Natural carbohydrate digestion enzyme inhibitors might be a viable option for blocking dietary carbohydrate absorption with fewer side effects than manufactured medicines. Alpha-amylase is a metalloenzyme that facilitates digestion by breaking down polysaccharides into smaller molecules such as maltose and maltotriose. It also contributes to elevated blood glucose levels and postprandial hyperglycemia. As a result, scientists are being urged to target α-amylase and create inhibitors that can slow down the release of glucose from carbohydrate chains and prolong its absorption, thereby resulting in lower postprandial plasma glucose levels. Natural α-amylase inhibitors derived from plants have gained popularity as safe and cost-effective alternatives. The bioactive components responsible for the inhibitory actions of various plant extracts have been identified through phytochemical research, paving the way for further development and application. The majority of the findings, however, are based on in vitro investigations. Only a few animal experiments and very few human investigations have confirmed these findings. Despite some promising results, additional investigation is needed to develop feasible anti-diabetic drugs based on plant-derived pancreatic α-amylase inhibitors. This review summarizes the most recent findings from research on plant-derived pancreatic α-amylase inhibitors, including plant extracts and plant-derived bioactive compounds. Furthermore, it offers insights into the structural aspects of the crucial therapeutic target, α-amylases, in addition to their interactions with inhibitors.

Design, synthesis, in vitro anti-α-glucosidase evaluations, and computational studies of new phthalimide-phenoxy-1,2,3-triazole-N-phenyl (or benzyl) acetamides as potential anti-diabetic agents

An important target in the treatment of type 2 diabetes is α-glucosidase. Inhibition of this enzyme led to delay in glucose absorption and decrease in postprandial hyperglycemia. A new series of phthalimide-phenoxy-1,2,3-triazole-N-phenyl (or benzyl) acetamides 11a-n were designed based on the reported potent α-glucosidase inhibitors. These compounds were synthesized and screened for their in vitro inhibitory activity against the latter enzyme. The majority of the evaluated compounds displayed high inhibition effects (IC₅₀ values in the range of 45.26 ± 0.03-491.68 ± 0.11 µM) as compared to the positive control acarbose (IC₅₀ value = 750.1 ± 0.23 µM). Among this series, compounds 11j and 11i represented the most potent α-glucosidase inhibitory activities with IC₅₀ values of 45.26 ± 0.03 and 46.25 ± 0.89 µM. Kinetic analysis revealed that the compound 11j is a competitive inhibitor with a K_i of 50.4 µM. Furthermore, the binding interactions of the most potent compounds in α-glucosidase active site were studied through molecular docking and molecular dynamics. The latter studies confirmed the obtained results through in vitro experiments. Furthermore, in silico pharmacokinetic study of the most potent compounds was also performed.

Phenolic Profiles, Antioxidant, and Hypoglycemic Activities of Ribes meyeri Fruits

Ribes meyeri is a Ribes genus in the Saxifragaceae family, which is used as both medicine and food. However, the active components and biological activities of R. meyeri fruits are still unknown. In this paper, the phenolic components and their antioxidant and hypoglycemic activities of R. meyeri fruits were studied. Firstly, a total of 42 phenolic components of R. meyeri fruits, including 26 anthocyanins, 9 flavonoids, and 7 phenolic acids, were tentatively identified using HPLC-QTOF-MS/MS, and the main four anthocyanins were quantified using UPLC-MS/MS. The result indicated that cyanidin-3-O-rutinoside is the main anthocyanin in the R. meyeri fruits. The anthocyanin fraction of R. meyeri fruits exhibited significant inhibitory activity on α-amylase and α-glucosidase. The anthocyanin fraction from R. meyeri fruits significantly increased the glucose uptake of 3T3-L1 adipocytes. This is the first study of a qualitative and quantitative analysis of the phenolics of R. meyeri fruits.

Natural products targeting inflammation-related metabolic disorders: A comprehensive review

Currently, the incidence of metabolic disorders is increasing, setting a challenge to global health. With major advancement in the diagnostic tools and clinical procedures, much has been known in the etiology of metabolic disorders and their corresponding pathophysiologies. In addition, the use of in vitro and in vivo experimental models prior to clinical studies has promoted numerous biomedical breakthroughs, including in the discovery and development of drug candidates to treat metabolic disorders. Indeed, chemicals isolated from natural products have been extensively studied as prospective drug candidates to manage diabetes, obesity, heart-related diseases, and cancer, partly due to their antioxidant and anti-inflammatory properties. Continuous efforts have been made in parallel to improve their bioactivity and bioavailability using selected drug delivery approaches. Here, we provide insights on recent progress in the role of inflammatory-mediated responses on the initiation of metabolic disorders, with particular reference to diabetes mellitus, obesity, heart-related diseases, and cancer. In addition, we discussed the prospective role of natural products in the management of diabetes, obesity, heart-related diseases, and cancers and provide lists of potential biological targets for high throughput screening in drug discovery and development. Lastly, we discussed findings observed in the preclinical and clinical studies prior to identifying suitable approaches on the phytochemical drug delivery systems that are potential to be used in the treatment of metabolic disorders.

Metabolites of Geum aleppicum and Sibbaldianthe bifurca: Diversity and α-Glucosidase Inhibitory Potential

α-Glucosidase inhibitors are essential in the treatment of diabetes mellitus. Plant-derived drugs are promising sources of new compounds with glucosidase-inhibiting ability. The Geum aleppicum Jacq. and Sibbaldianthe bifurca (L.) Kurtto & T.Erikss. herbs are used in many traditional medical systems to treat diabetes. In this study, metabolites of the G. aleppicum and S. bifurca herbs in active growth, flowering, and fruiting stages were investigated using high-performance liquid chromatography with photodiode array and electrospray ionization triple quadrupole mass spectrometric detection (HPLC-PDA-ESI-tQ-MS/MS). In total, 29 compounds in G. aleppicum and 41 components in S. bifurca were identified including carbohydrates, organic acids, benzoic and ellagic acid derivatives, ellagitannins, flavonoids, and triterpenoids. Gemin A, miquelianin, niga-ichigoside F1, and 3,4-dihydroxybenzoic acid 4-O-glucoside were the dominant compounds in the G. aleppicum herb, while guaiaverin, miquelianin, tellimagrandin II₂, casuarictin, and glucose were prevailing compounds in the S. bifurca herb. On the basis of HPLC activity-based profiling of the G. aleppicum herb extract, the most pronounced inhibition of α-glucosidase was observed for gemin A and quercetin-3-O-glucuronide. The latter compound and quercetin-3-O-arabinoside demonstrated maximal inhibition of α-glucosidase in the S. bifurca herb extract. The obtained results confirm the prospects of using these plant compounds as possible sources of hypoglycemic nutraceuticals.

Screening and Elucidation of Chemical Structures of Novel Mammalian α-Glucosidase Inhibitors Targeting Anti-Diabetes Drug from Herbals Used by E De Ethnic Tribe in Vietnam

Among ten extracts of indigenous medicinal plants, the MeOH extract of Terminalia triptera Stapf. (TTS) showed the most efficient mammalian α-glucosidase inhibition for the first time. The data of screening bioactive parts used indicated that the TTS trunk bark and leaves extracts demonstrated comparable and higher effects compared to acarbose, a commercial anti-diabetic drug, with half-maximal inhibitory concentration (IC50) values of 181, 331, and 309 µg/mL, respectively. Further bioassay-guided purification led to the isolation of three active compounds from the TTS trunk bark extract and identified as (-)-epicatechin (1), eschweilenol C (2), and gallic acid (3). Of these, compounds 1 and 2 were determined as novel and potent mammalian α-glucosidase inhibitors. The virtual study indicated that these compounds bind to α-glucosidase (Q6P7A9) with acceptable RMSD values (1.16-1.56 Å) and good binding energy (DS values in the range of -11.4 to -12.8 kcal/mol) by interacting with various prominent amino acids to generate five and six linkages, respectively. The data of Lipinski's rule of five and absorption, distribution, metabolism, excretion and toxicity (ADMET)-based pharmacokinetics and pharmacology revealed that these purified compounds possess anti-diabetic drug properties, and the compounds are almost not toxic for human use. Thus, the findings of this work suggested that (-)-epicatechin and eschweilenol C are novel potential mammalian α-glucosidase inhibitor candidates for type 2 diabetes treatment.

Annona cherimola Miller and Its Flavonoids, an Important Source of Products for the Treatment of Diabetes Mellitus: In Vivo and In Silico Evaluations

The antihyperglycemic activity of ethanolic extract from Annona cherimola Miller (EEAch) and its products were evaluated using in vivo and in silico assays. An α-glucosidase inhibition was evaluated with oral sucrose tolerance tests (OSTT) and molecular docking studies using acarbose as the control. SGLT1 inhibition was evaluated with an oral glucose tolerance test (OGTT) and molecular docking studies using canagliflozin as the control. Among all products tested, EEAc, the aqueous residual fraction (AcRFr), rutin, and myricetin reduced the hyperglycemia in DM2 mice. During the carbohydrate tolerance tests, all the treatments reduced the postprandial peak such as the control drugs. In the molecular docking studies, rutin showed more affinity in inhibiting α-glucosidase enzymes and myricetin in inhibiting the SGLT1 cotransporter, showing ∆G values of -6.03 and -3.32 kcal/mol^-1, respectively, in α-glucosidase enzymes. In the case of the SGLT1 cotransporter, molecular docking showed ∆G values of 22.82 and -7.89 in rutin and myricetin, respectively. This research sorts in vivo and in silico pharmacological studies regarding the use of A. cherimola leaves as a source for the development of new potential antidiabetic agents for T2D control, such as flavonoids rutin and myricetin.

Potential α-Glucosidase Inhibitors from the Deep-Sea Sediment-Derived Fungus Aspergillus insulicola

Three new phenolic compounds, epicocconigrones C–D (1–2) and flavimycin C (3), together with six known phenolic compounds: epicocconigrone A (4); 2-(10-formyl-11,13-dihydroxy-12-methoxy-14-methyl)-6,7-dihydroxy-5-methyl-4-benzofurancarboxaldehyde (5); epicoccolide B (6); eleganketal A (7); 1,3-dihydro-5-methoxy-7-methylisobenzofuran (8); and 2,3,4-trihydroxy-6-(hydroxymethyl)-5-methylbenzyl-alcohol (9), were isolated from fermentation cultures of a deep-sea sediment-derived fungus, Aspergillus insulicola. Their planar structures were elucidated based on the 1D and 2D NMR spectra and HRESIMS data. The absolute configurations of compounds 1–3 were determined by ECD calculations. Compound 3 represented a rare fully symmetrical isobenzofuran dimer. All compounds were evaluated for their α-glucosidase inhibitory activity, and compounds 1, 4–7, and 9 exhibited more potent α-glucosidase inhibitory effect with IC50 values ranging from 17.04 to 292.47 μM than positive control acarbose with IC50 value of 822.97 μM, indicating that these phenolic compounds could be promising lead compounds of new hypoglycemic drugs.

Value-Added Compounds with Antimicrobial, Antioxidant, and Enzyme-Inhibitory Effects from Post-Distillation and Post-Supercritical CO2 Extraction By-Products of Rosemary

Hydrodistillation is the main technique to obtain essential oils from rosemary for the aroma industry. However, this technique is wasteful, producing numerous by-products (residual water, spent materials) that are usually discarded in the environment. Supercritical CO₂ (SC-CO₂) extraction is considered an alternative greener technology for producing aroma compounds. However, there have been no discussions about the spent plant material leftover. Therefore, this work investigated the chemical profile (GC-MS, LC-HRMS/MS) and multi-biological activity (antimicrobial, antioxidant, enzyme inhibitory) of several raw rosemary materials (essential oil, SC-CO₂ extracts, solvent extracts) and by-products/waste materials (post-distillation residual water, spent plant material extracts, and post-supercritical CO₂ spent plant material extracts). More than 55 volatile organic compounds (e.g., pinene, eucalyptol, borneol, camphor, caryophyllene, etc.) were identified in the rosemary essential oil and SC-CO₂ extracts. The LC-HRMS/MS profiling of the solvent extracts revealed around 25 specialized metabolites (e.g., caffeic acid, rosmarinic acid, salvianolic acids, luteolin derivatives, rosmanol derivatives, carnosol derivatives, etc.). Minimum inhibitory concentrations of 15.6-62.5 mg/L were obtained for some rosemary extracts against Micrococcus luteus, Bacilus cereus, or Staphylococcus aureus MRSA. Evaluated in six different in vitro tests, the antioxidant potential revealed strong activity for the polyphenol-containing extracts. In contrast, the terpene-rich extracts were more potent in inhibiting various key enzymes (e.g., acetylcholinesterase, butyrylcholinesterase, tyrosinase, amylase, and glucosidase). The current work brings new insightful contributions to the continuously developing body of knowledge about the valorization of rosemary by-products as a low-cost source of high-added-value constituents in the food, pharmaceutical, and cosmeceutical industries.

Integrated metabolite analysis and health-relevant in vitro functionality of white, red, and orange maize (Zea mays L.) from the Peruvian Andean race Cabanita at different maturity stages

The high maize (Zea mays L.) diversity in Peru has been recognized worldwide, but the investigation focused on its integral health-relevant and bioactive characterization is limited. Therefore, this research aimed at studying the variability of the primary and the secondary (free and dietary fiber-bound phenolic, and carotenoid compounds) metabolites of three maize types (white, red, and orange) from the Peruvian Andean race Cabanita at different maturity stages (milk-S1, dough-S2, and mature-S3) using targeted and untargeted methods. In addition, their antioxidant potential, and α-amylase and α-glucosidase inhibitory activities relevant for hyperglycemia management were investigated using in vitro models. Results revealed a high effect of the maize type and the maturity stage. All maize types had hydroxybenzoic and hydroxycinnamic acids in their free phenolic fractions, whereas major bound phenolic compounds were ferulic acid, ferulic acid derivatives, and p-coumaric acid. Flavonoids such as luteolin derivatives and anthocyanins were specific in the orange and red maize, respectively. The orange and red groups showed higher phenolic ranges (free + bound) (223.9-274.4 mg/100 g DW, 193.4- 229.8 mg/100 g DW for the orange and red maize, respectively) than the white maize (162.2-225.0 mg/100 g DW). Xanthophylls (lutein, zeaxanthin, neoxanthin, and a lutein isomer) were detected in all maize types. However, the orange maize showed the highest total carotenoid contents (3.19-5.87 μg/g DW). Most phenolic and carotenoid compounds decreased with kernel maturity in all cases. In relation to the primary metabolites, all maize types had similar fatty acid contents (linoleic acid > oleic acid > palmitic acid > α-linolenic acid > stearic acid) which increased with kernel development. Simple sugars, alcohols, amino acids, free fatty acids, organic acids, amines, and phytosterols declined along with grain maturity and were overall more abundant in white maize at S1. The in vitro functionality was similar among Cabanita maize types, but it decreased with the grain development, and showed a high correlation with the hydrophilic free phenolic fraction. Current results suggest that the nutraceutical characteristics of orange and white Cabanita maize are better at S1 and S2 stages while the red maize would be more beneficial at S3.