Rb2 inhibits α-glucosidase and regulates glucose metabolism by activating AMPK pathways in HepG2 cells

Anti-Hyperglycemic Effects of Thai Herbal Medicines

This study aims to investigate selected medicinal plants' anti-oxidative and antihyperglycemic activities to develop an effective remedy for lowering blood glucose levels and/or reducing diabetes complications. Thai medicinal plants, reported to have blood sugar-lowering effects, were selected for the study: Coccinia grandis, Gymnema inodorum, Gynostemma pentaphyllum, Hibiscus sabdariffa, Momordica charantia, Morus alba, and Zingiber officinale. Each species was extracted by Soxhlet's extraction using ethanol as solvent. The ethanolic crude extract of each species was then evaluated for its phytochemicals, anti-oxidant, and antihyperglycemic activities. The results showed that the extract of Z. officinale gave the highest values of total phenolic and total flavonoid content (167.95 mg gallic acid equivalents (GAE)/g and 81.70 mg CE/g, respectively). Anti-oxidant activity was determined using DPPH and ABTS radical scavenging activity. Among the ethanolic extracts, Z. officinale exhibited the highest anti-oxidant activity with IC50 values of 19.16 and 8.53 µg/mL, respectively. The antihyperglycemic activity was assessed using α-glucosidase inhibitory and glucose consumption activities. M. alba and G. pentaphyllum demonstrated the highest α-glucosidase inhibitory activity among the ethanolic extracts, with IC50 values of 134.40 and 329.97 µg/mL, respectively. Z. officinale and H. sabdariffa showed the highest percentage of glucose consumption activity in induced insulin-resistant HepG2 cells at a concentration of 50 µg/mL with 145.16 and 107.03%, respectively. The results from α-glucosidase inhibitory and glucose consumption activities were developed as an effective antihyperglycemic remedy. Among the remedies tested, the R1 remedy exhibited the highest potential for reducing blood glucose levels, with an IC50 value of 122.10 µg/mL. Therefore, the R1 remedy should be further studied for its effects on animals.

Novel isoniazid-hydrazone derivatives induce cell growth inhibition, cell cycle arrest and apoptosis via mitochondria-dependent caspase activation and PI3K/AKT inhibition

In this study, seven isoniazid-hydrazone derivatives (3a-g) were synthesized and their structures elucidated by chromatographic techniques, and then the antiproliferative effects of these compounds on various cancer cells were tested. The advanced anticancer mechanism of the most potent compound was then investigated. Antiproliferative activities of the synthesized compounds were evaluated on human breast cancer MCF-7, lung cancer A-549, colon cancer HT-29, and non-cancerous mouse fibroblast 3T3-L1 cell lines by XTT assay. Flow cytometry analysis were carried out to determine cell cycle distribution, apoptosis, mitochondrial membrane potential, multi-caspase activity, and expression of PI3K/AKT signaling pathway. The XTT results showed that all the title molecules displayed cytotoxic activity at varying strengths in different dose ranges, and among them, the strongest cytotoxic effect and high selectivity were exerted by 3d against MCF-7 cells with the IC50 value of 11.35 µM and selectivity index of 8.65. Flow cytometry results revealed that compound 3d induced apoptosis through mitochondrial membrane disruption and multi-caspase activation in MCF-7 cells. It also inhibited the cell proliferation via inhibition of expression of PI3K/AKT and arrested the cell cycle at G0/G1 phase. In conclusion, all these data disclosed that among the synthesized compounds, 3d is notable for in vivo anticancer studies.

Sahlep (Dactylorhiza osmanica): Phytochemical Analyses by LC-HRMS, Molecular Docking, Antioxidant Activity, and Enzyme Inhibition Profiles

Studies have shown an inverse correlation among age-related illnesses like coronary heart disease and cancer and intake of fruit and vegetable. Given the probable health benefits of natural antioxidants from plants, research on them has increased. Dactylorhiza osmanica is consumed as a food and traditional medicine plant in some regions of Turkey, so evaluation of the biological ability of this species is important. In this study, the amount of phenolic content (LC-HRMS), antioxidant activities and enzyme inhibitory properties of an endemic plant, D. osmanica, were investigated. The antioxidant capacities of an ethanol extract of D. osmanica aerial parts (EDOA) and roots (EDOR) were evaluated with various antioxidant methods. Additionally, the enzyme inhibitory effects of EDOA and EDOR were examined against acetylcholinesterase (AChE), α-glycosidase, and α-amylase enzymes, which are associated with common and global Alzheimer's disease and diabetes mellitus. The IC50 values of EDOA against the enzymes were found to be 1.809, 1.098, and 0.726 mg/mL, respectively; and the IC50 values of EDOR against the enzymes were found to be 2.466, 0.442, and 0.415 mg/mL, respectively. Additionally, LC-HRMS analyses revealed p-Coumaric acid as the most plentiful phenolic in both EDOA (541.49 mg/g) and EDOR (559.22 mg/g). Furthermore, the molecular docking interaction of p-coumaric acid, quercitrin, and vanillic acid, which are the most plentiful phenolic compounds in the extracts, with AChE, α-glucosidase, and α-amylase, were evaluated using AutoDock Vina software. The rich phenolic content and the effective antioxidant ability and enzyme inhibition potentials of EDOA and EDOR may support the plant's widespread food and traditional medicinal uses.

A new specific method for isolation of tomentosin with a high yield from Inula viscosa (L.) and determination of its bioactivities

INTRODUCTION

Tomentosin, the characteristic component of Inula viscosa (L.) is an important sesquiterpene lactone with anticarcinogenic effects. Methods of obtaining pure tomentosin are not sufficient for anticancer drug research.

OBJECTIVES

This study aims to develop a specific method to isolate tomentosin from I. viscosa with high yield. It also aims to investigate the inhibitory effects of tomentosin on human carbonic anhydrase I (hCAI), human carbonic anhydrase II (hCAII), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-glucosidase, and α-amylase enzymes.

MATERIAL AND METHODS

Tomentosin was purified by a specific column chromatography method. The content of tomentosin in dichloromethane, dichloromethane by Soxhlet method, ethanol and ethanol by Soxhlet method extracts of I. viscosa was determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Half maximal inhibitory concentration (IC₅₀ ) and inhibition constant (K_i ) values were calculated to determine in vitro enzyme inhibition effects.

RESULTS

Tomentosin was isolated in high yield (0.64%). The IC₅₀ and K_i values for tomentosin were calculated as 5.00 ± 0.19 (r = 0.9688) and 4.62 ± 0.10 μM for hCAI, 5.40 ± 0.26 (r = 0.9677) and 5.22 ± 0.31 μM for hCAII, 6.75 ± 0.208 (r = 0.9891) and 3.75 ± 0.27 μM for AChE, 6.67 ± 0.307 (r = 0.9820) and 0.51 ± 0.11 μM for BChE, 26.61 ± 0.236 (r = 0.9815) and 2.61 ± 0.71 μM for α-glucosidase and 26.89 ± 1.54 μM (r = 0.9670) for α-amylase, respectively.

CONCLUSION

Tomentosin was isolated in high yield from the paste-like extract of I. viscosa compared to the positive controls, it was determined that tomentosin was weakly effective against hCAI, hCAII, AChE and BChE, but thoroughly effective against α-glucosidase and α-amylase. These results suggested that tomentosin has α-glucosidase and α-amylase inhibitor potential.

New 4-phenylpiperazine-carbodithioate-N-phenylacetamide hybrids: Synthesis, in vitro and in silico evaluations against cholinesterase and α-glucosidase enzymes

A series of novel 4-phenylpiperazine-carbodithioate-N-phenylacetamide hybrids (6a-n) was designed, synthesized, and evaluated for their in vitro inhibitory activity against the metabolic enzymes, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glucosidase. The obtained results showed that most of the synthesized compounds exhibited high to good anti-AChE and anti-BChE activity in the range of nanomolar concentrations in comparison to tacrine as a positive control. Molecular modeling of the most potent compounds 6e and 6i demonstrated that these compounds interacted with important residues of the AChE and BChE active sites. Moreover, all the newly synthesized compounds 6a-n had significant K_i values against α-glucosidase when compared with the positive control acarbose. Representatively, N-2-fluorophenylacetamide derivative 6l, with a K_i value of 0.98 nM as the most potent compound, was 126 times more potent than acarbose with a K_i value of 123.70 nM. This compound also fitted in the α-glucosidase active site and interacted with key residues. An in silico study of the druglikeness/absorption, distribution, metabolism, and excretion (ADME)/toxicity profile of the selected compounds 6e, 6i, and 6l predicts that these compounds are drug-like and have the appropriate properties in terms of ADME and toxicity.

A Pre-clinical Trial Study: Anti-human Colon Cancer Effect of Thalassiolin B in vitro with Enzymes Inhibition Effects and Molecular Docking Studies

In this study, it is recorded the inhibition effect of Thalassiolin B on aldose reductase, alpha-glucosidase and alpha-amylase enzymes. In the next step, the molecular docking method was used to compare the biological activities of the Thalassiolin B molecule against enzymes formed from the assembly of proteins. In these calculations, the enzymes used are Aldose reductase, Alpha-Amylase, and Alpha-Glucosidase, respectively. After the docking method, ADME/T analysis of Thalassiolin B molecule was performed to be used as a drug in the pharmaceutical industry. In the MTT assay, the anti-human colon cancer properties of Thalassiolin B against EB, LS1034, and SW480 cell lines were investigated. The cell viability of Thalassiolin B was very low against human colon cancer cell lines without any cytotoxicity on the human normal (HUVEC) cell line. The IC₅₀ of the Thalassiolin B against EB, LS1034, and SW480 were 483, 252, and 236 µg/mL, respectively. Thereby, the best cytotoxicity results and anti-human colon cancer potentials of our Thalassiolin B were observed in the case of the SW480 cell line. Maybe the anti-human colon cancer properties of Thalassiolin B are related to their antioxidant effects.

Selenourea and thiourea derivatives of chiral and achiral enetetramines: Synthesis, characterization and enzyme inhibitory properties

A series of chiral and achiral cyclic seleno- and thiourea compounds bearing benzyl groups on N-atoms were prepared from enetetramines and appropriate Group VI elements in good yields. All the synthesized compounds were characterized by elemental analysis, FT-IR, ¹H NMR and ¹³C NMR spectroscopy, and the molecular and crystal structures of (R,R)-4b and (R,R)-5b were confirmed by the single-crystal X-ray diffraction method. These assayed for their activities against metabolic enzymes acetylcholinesterase, butyrylcholinesterase, and α-glycosidase. These selenourea and thiourea derivatives of chiral and achiral enetetramines effectively inhibit AChE and BChE with IC₅₀ values in the range of 3.32-11.36 and 1.47-9.73 µM, respectively. Also, these compounds inhibited α-glycosidase enzyme with IC₅₀ values varying between 1.37 and 8.53 µM. The results indicated that all the synthesized compounds exhibited excellent inhibitory activities against mentioned enzymes as compared with standard inhibitors. Representatively, the most potent compound against α-glycosidase enzyme, (S,S)-5b, was 12-times more potent than standard inhibitor acarbose; 7b and 8a as most potent compounds against cholinesterase enzymes, were around 5 and 13-times more potent than standard inhibitor tacrine against achethylcholinesterase (AChE) and butyrylcholinesterase (BChE), respectively.

Benzenesulfonamide derivatives as potent acetylcholinesterase, α-glycosidase, and glutathione S-transferase inhibitors: biological evaluation and molecular docking studies

Sulfonamide derivatives exhibit a wide biological activity and can function as potential medical molecules in the development of a drug. Studies have reported that the compounds have an effect on many enzymes. In this study, the derivatives of amine sulfonamide (1i-11i) were prepared with reduced imine compounds (1-11) with NaBH4 in methanol. The synthesized compounds were fully characterized by spectral data and analytical. The effect of the synthesized derivatives on acetylcholinesterase (AChE), glutathione S-transferase (GST) and α-glycosidase (α-GLY) enzymes were determined. For the AChE and α-GLY, the most powerful inhibition was observed on 10 and 10i series with KI value in the range 2.26 ± 0.45-3.57 ± 0.97 and 95.73 ± 13.67-102.45 ± 11.72 µM, respectively. KI values of the series for GST were found in the range of 22.76 ± 1.23-49.29 ± 4.49. Finally, the compounds have a stronger inhibitor in lower concentrations by the attachment of functional electronegative groups such as two halogens (-Br and -CI), -OH to the benzene ring and -SO2NH2. The crystal structures of AChE, α-GLY, and GST in complex with selected derivatives 4 and 10 show the importance of the functional moieties in the binding modes within the receptors.Communicated by Ramaswamy H. Sarma.

Dietary anthocyanins as potential natural modulators for the prevention and treatment of non-alcoholic fatty liver disease: A comprehensive review

Nonalcoholic fatty liver disease (NAFLD) refers to a metabolic syndrome linked with type 2 diabetes mellitus, obesity, and cardiovascular diseases. It is characterized by the accumulation of triglycerides in the hepatocytes in the absence of alcohol consumption. The prevalence of NAFLD has abruptly increased worldwide, with no effective treatment yet available. Anthocyanins (ACNs) belong to the flavonoid subclass of polyphenols, are commonly present in various edible plants, and possess a broad array of health-promoting properties. ACNs have been shown to have strong potential to combat NAFLD. We critically assessed the literature regarding the pharmacological mechanisms and biopharmaceutical features of the action of ACNs on NAFLD in humans and animal models. We found that ACNs ameliorate NAFLD by improving lipid and glucose metabolism, increasing antioxidant and anti-inflammatory activities, and regulating gut microbiota dysbiosis. In conclusion, ACNs have potential to attenuate NAFLD. However, further mechanistic studies are required to confirm these beneficial impacts of ACNs on NAFLD.

Polyphenolic inhibition of enterocytic starch digestion enzymes and glucose transporters for managing type 2 diabetes may be reduced in food systems

With the current global surge in diabetes cases, there is a growing interest in slowing and managing diabetes and its effects. While there are medications that can be used, they have adverse side effects such as hypoglycemia and weight gain. To overcome these problems, bioactive compounds commonly found in fruits, vegetables and cereal grains are used to slow starch digestion and transport of simple sugars across the intestinal epithelia thereby reducing plasma blood glucose spike. These effects are achieved through inhibition of amylases, glucosidases and glucose transporters present in the gastrointestinal tract and brush boarder membrane. The extent of inhibition by polyphenols is dependent on molecular structure, doses and food matrix. Glycemic lowering effect of polyphenols have been demonstrated both in in vivo and in vitro studies. However, when these compounds are incorporated in food systems, they can interact with other polymers in the food matrix leading to lesser inhibition of digestion and/or glucose transporters compared to isolated or pure compounds as often witnessed in most in vitro studies.

Synthesis, characterization, crystal structure, α-glycosidase, and acetylcholinesterase inhibitory properties of 1,3-disubstituted benzimidazolium salts

Chloro-/fluorobenzyl-substituted benzimidazolium salts were synthesized from the reaction of 4-fluorobenzyl/2-chloro-4-fluorobenzyl-substituted benzimidazole and chlorinated aromatic hydrocarbons. They were characterized using various spectroscopic techniques (Fourier-transform infrared and nuclear magnetic resonance) and elemental analysis. In addition, the crystal structures of the complexes 1a -d and 2b were determined by single-crystal X-ray diffraction methods. These compounds were crystallized in the triclinic crystal system with a P-1 space group. The crystal packing of all complexes is dominated by O-H⋯Cl hydrogen bonds, which link the water molecules and chloride anions, forming a chloride-water tetrameric cluster. These synthesized salts were found to be effective inhibitors for α-glycosidase and acetylcholinesterase (AChE), with K_i values ranging from 45.77 ± 6.83 to 102.61 ± 11.56 µM for α-glycosidase and 0.94 ± 0.14 to 10.24 ± 1.58 µM for AChE. AChE converts acetylcholine into choline and acetic acid, thus causing the return of a cholinergic neuron to its resting state. Discovering AChE and α-glycosidase inhibitors is one of the important ways to develop new drugs for the treatment of Alzheimer's disease and diabetes.

Application 2D Descriptors and Artificial Neural Networks for Beta-Glucosidase Inhibitors Screening

Beta-glucosidase inhibitors play important medical and biological roles. In this study, simple two-variable artificial neural network (ANN) classification models were developed for beta-glucosidase inhibitors screening. All bioassay data were obtained from the ChEMBL database. The classifiers were generated using 2D molecular descriptors and the data miner tool available in the STATISTICA package (STATISTICA Automated Neural Networks, SANN). In order to evaluate the models' accuracy and select the best classifiers among automatically generated SANNs, the Matthews correlation coefficient (MCC) was used. The application of the combination of maxHBint3 and SpMax8_Bhs descriptors leads to the highest predicting abilities of SANNs, as evidenced by the averaged test set prediction results (MCC = 0.748) calculated for ten different dataset splits. Additionally, the models were analyzed employing receiver operating characteristics (ROC) and cumulative gain charts. The thirteen final classifiers obtained as a result of the model development procedure were applied for a natural compounds collection available in the BIOFACQUIM database. As a result of this beta-glucosidase inhibitors screening, eight compounds were univocally classified as active by all SANNs.

Secondary metabolites of Helichrysum plicatum DC. subsp. plicatum flowers as strong carbonic anhydrase, cholinesterase and α-glycosidase inhibitors

Helichrysum plicatum species are used in Turkish folk medicine as lithagogue, diuretic, and nephritic. Research on the methanol (MeOH) extract of flowers of H. plicatum DC. subsp. plicatum resulted in the isolation of eight known compounds (1-8). The chemical structures of the compounds were determined as β-sitosterol (1), apigenin (2), nonacosanoic acid (3), astragalin (4), β-sitosterol-3-O-β-D-glucopyranoside (5), helichrysin A (6), helichrysin B (7), and isosalipurposide (8) by spectroscopic and chromatographic/spectrometric methods, including 1D and 2D nuclear magnetic resonance and liquid chromatography-tandem mass spectrometry. Nonacosanoic acid (3) was isolated for the first time from H. plicatum DC. subsp. plicatum. The MeOH extract and isolated compounds were evaluated for their in vitro human carbonic anhydrase I (hCAI) and II (hCAII), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glycosidase inhibitory activities. The IC50 values of H. plicatum DC. subsp. plicatum MeOH extract for hCAI, hCAII, AChE, BChE, and α-glycosidase were found to be 77.87, 52.90, 115.50, 117.46, and 81.53 mg/mL, respectively. The compounds showed IC50 values of 1.43-4.47, 1.40-4.32, 1.69-2.90, 1.09-3.89, and 1.61-3.80 μM against hCAI, hCAII, AChE, BChE, and α-glycosidase, respectively. In summary, H. plicatum DC. subsp. plicatum secondary metabolites demonstrated strong inhibitory effects especially against hCAI and hCAII, whereas the MeOH extract showed a weak inhibitory effect on all enzymes.

Steamed Panax notoginseng Attenuates Anemia in Mice With Blood Deficiency Syndrome via Regulating Hematopoietic Factors and JAK-STAT Pathway

Panax notoginseng (Burk.) F. H. Chen is a medicinal herb used to treat blood disorders since ancient times, of which the steamed form exhibits the anti-anemia effect and acts with a “blood-tonifying” function according to traditional use. The present study aimed to investigate the anti-anemia effect and underlying mechanism of steamed P. notoginseng (SPN) on mice with blood deficiency syndrome induced by chemotherapy. Blood deficiency syndrome was induced in mice by cyclophosphamide and acetylphenylhydrazine. A number of peripheral blood cells and organs (liver, kidney, and spleen) coefficients were measured. The mRNA expression of hematopoietic function-related cytokines in the bone marrow of mice was detected by RT-qPCR. The janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway was screened based on our previous analysis by network pharmacology. The expression of related proteins and cell cycle factors predicted in the pathway was determined by Western blot and RT-qPCR. SPN could significantly increase the numbers of peripheral blood cells and reverse the enlargement of spleen in a dose-dependent manner. The quantities of related hematopoietic factors in bone marrow were also increased significantly after SPN administration. SPN was involved in the cell cycle reaction and activation of immune cells through the JAK-STAT pathway, which could promote the hematopoiesis.

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.

Anti-inflammatory Property of AMP-activated Protein Kinase

BACKGROUND

One of the many debated topics in inflammation research is whether this scenario is really an accelerated form of human wound healing and immunityboosting or a push towards autoimmune diseases. The answer requires a better understanding of the normal inflammatory process, including the molecular pathology underlying the possible outcomes. Exciting recent investigations regarding severe human inflammatory disorders and autoimmune conditions have implicated molecular changes that are also linked to normal immunity, such as triggering factors, switching on and off, the influence of other diseases and faulty stem cell homeostasis, in disease progression and development.

METHODS

We gathered around and collected recent online researches on immunity, inflammation, inflammatory disorders and AMPK. We basically searched PubMed, Scopus and Google Scholar to assemble the studies which were published since 2010.

RESULTS

Our findings suggested that inflammation and related disorders are on the verge and interfere in the treatment of other diseases. AMPK serves as a key component that prevents various kinds of inflammatory signaling. In addition, our table and hypothetical figures may open a new door in inflammation research, which could be a greater therapeutic target for controlling diabetes, obesity, insulin resistance and preventing autoimmune diseases.

CONCLUSION

The relationship between immunity and inflammation becomes easily apparent. Yet, the essence of inflammation turns out to be so startling that the theory may not be instantly established and many possible arguments are raised for its clearance. However, this study might be able to reveal some possible approaches where AMPK can reduce or prevent inflammatory disorders.

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.

Inhibition profiles of Voriconazole against acetylcholinesterase, α-glycosidase, and human carbonic anhydrase I and II isoenzymes

In this work, the inhibitory activity of Voriconazole was measured against some metabolic enzymes, including human carbonic anhydrase (hCA) I and II isoenzymes, acetylcholinesterase (AChE), and α-glycosidase; the results were compared with standard compounds including acetazolamide, tacrine, and acarbose. Half maximal inhibition concentration (IC₅₀ ) values were obtained from the enzyme activity (%)-[Voriconazole] graphs, whereas K_i values were calculated from the Lineweaver-Burk graphs. According to the results, the IC₅₀ value of Voriconazole was 40.77 nM for α-glycosidase, while the mean inhibition constant (K_i ) value was 17.47 ± 1.51 nM for α-glycosidase. The results make an important contribution to drug design and have pharmacological applications. In addition, the Voriconazole compound demonstrated excellent inhibitory effects against AChE and hCA isoforms I and II. Voriconazole had K_i values of 29.13 ± 3.57 nM against hCA I, 15.92 ± 1.90 nM against hCA II, and 10.50 ± 2.46 nM against AChE.

The mechanism of damage by trace amounts of acetamiprid to the midgut of the silkworm, Bombyx mori

Acetamiprid is widely used for agricultural pest control. However, it remains poorly understood whether the environmental residues of acetamiprid have the potential effects on economic insect. In this study, we evaluated the effects of acetamiprid on silkworm growth and development. The exposure to trace amounts of acetamiprid significantly decreased body weight, viability, and spinning ability. In addition, the activity of trypsin in the midgut was decreased after exposure. DGE and KEGG pathway enrichment analysis revealed that the significantly differentially expressed genes were mainly involved in nutrient metabolism, stress responses, and inflammation pathways. These results, in combination with hematoxylin-eosin staining and transmission electron microscopy, indicated that acetamiprid could cause oxidative damage to midgut, lead to inflammatory responses, and affect the activities of midgut digestive enzymes, thus resulting in abnormal growth and development. Our findings greatly contributed to the evaluation of the effects of acetamiprid residues on other nontarget beneficial insect.

Inhibitory effects of selected antibiotics on the activities of α-amylase and α-glucosidase: In-vitro, in-vivo and theoretical studies

Antibiotics are effective drugs that are used to treat infectious diseases either by killing bacteria or slowing down their growth. The well-adapted structural features of antibiotics for the inhibition/activation of enzymes include several available hydrogen bond (H-bond) acceptors and donors, flexible backbone and hydrophobic nature. The substrates of α-amylase and α-glucosidase, known as key absorbing enzymes, have functional groups (OH groups) rembling antibiotics. Given the possibility of developing in diabetics and the significant association between diabetes and infection, the present study was conducted to investigate the influences of tetracycline (TET), kanamycin (KANA), lincomycin (LIN), erythromycin (ERM) and azithromycin (AZM) on α-glucosidase and α-amylase activities with calculating IC₅₀ and K_i values. Also, the efficacy of antibiotics after oral administration was evaluated by analysis of blood glucose concentrations in rats, as well as a molecular docking analysis was explored. α-glucosidase and α-amylase activities were inhibited in a dose dependent fashion by TET with an IC₅₀ of 38.7 ± 1.4 and 47.8 ± 3.2 μM respectively, by KANA with an IC₅₀ of 46.2 ± 1.6 and 65.1 ± 1.6, by LIN with an IC₅₀ of 59.1 ± 2.1 and 51.3 ± 4.1, by ERM with an IC₅₀ of 94.9 ± 4.7 and 65.7 ± 3.8 and by AZM with an IC₅₀ of 69.4 ± 4.4 and 103.6 ± 6.2. Moreover, the K_i values of TET were calculated as 4.4 ± 0.6 and 8.4 ± 0.8 μM for α-glucosidase and α-amylase in a competitive-mode and mixed-mode inhibition. In addition, to communicate with the active site of α-glucosidase and α-amylase respectively, TET presented a binding energy of -9.8 and -8.8 kcal/mol, KANA -7.9 and -7.1, LIN -7.8 and -6.7, ERM -6.8 and -6.4, and AZM -6.4 and -7.5 kcal/mol. In-vivo studies also suggested a decrease in the blood glucose concentration after administering TET compared to the positive controls (P < 0.01). The results obtained from the present research can therefore help the scientific community explore the possible interconnection between the clinical side-effects of antibiotics and their α-glucosidase and α-amylase inhibitory properties, as the target enzymes in hypoglycemia conditions.

Antidiabetic properties of dietary phenolic compounds: Inhibition effects on α-amylase, aldose reductase, and α-glycosidase

Aldose reductase (AR), α-amylase, and α-glycosidase are vital enzymes to prevent diabetic complications. Here, AR was purified from sheep kidney using elementary methods with 111.11-purification fold and with 0.85% purification yield. The interactions between some phenolic compounds and the AR, α-glycosidase, and α-amylase enzyme were determined. It was found that phenolic compounds exhibit potential inhibitor properties for these enzymes. For α-amylase, studied phenolic compounds showed IC₅₀ values in the range of 601.56-2,067.78 nM. For α-glycosidase, K_i values were found in the range of 169.25 ± 27.22-572.88 ± 106.76 nM. For AR, K_i values in the range of 8.48 ± 0.56-43.26 ± 7.63 µM. However, genistein showed the best inhibition effect toward AR and α-glycosidase, but delphinidin chloride exhibited the best inhibition effect against α-amylase enzyme. We determined that all compounds showed noncompetitive inhibition effect against AR and α-glycosidase. Also, studied phenolic compounds may be useful in the prevention or treatment of diabetic complications.

Rhizoma coptidis as a Potential Treatment Agent for Type 2 Diabetes Mellitus and the Underlying Mechanisms: A Review

Diabetes mellitus, especially type 2 diabetes mellitus (T2DM), has become a significant public health burden. Rhizoma coptidis (RC), known as Huang Lian, is widely used for treating diabetes in China. The bioactive compounds of RC, especially alkaloids, have the potential to suppress T2DM-induced lesions, including diabetic vascular dysfunction, diabetic heart disease, diabetic hyperlipidemia, diabetic nephropathy, diabetic encephalopathy, diabetic osteopathy, diabetic enteropathy, and diabetic retinopathy. This review summarizes the effects of RC and its bioactive compounds on T2DM and T2DM complications. Less research has been conducted on non-alkaloid fractions of RC, which may exert synergistic action with alkaloids. Moreover, we summarized the pharmacokinetic properties and structure-activity relationships of RC on T2DM with reference to extant literature and showed clearly that RC has potential therapeutic effect on T2DM.

Novel 2-aminopyridine liganded Pd(II) N-heterocyclic carbene complexes: Synthesis, characterization, crystal structure and bioactivity properties

In this work, the synthesis, crystal structure, characterization, and enzyme inhibition effects of the novel a series of 2-aminopyridine liganded Pd(II) N-heterocyclic carbene (NHC) complexes were examined. These complexes of the Pd-based were synthesized from PEPPSI complexes and 2-aminopyridine. The novel complexes were characterized by using ¹³C NMR, ¹H NMR, elemental analysis, and FTIR spectroscopy techniques. Also, crystal structures of the two compounds were recorded by using single-crystal X-ray diffraction assay. Also, these complexes were tested toward some metabolic enzymes like α-glycosidase, aldose reductase, butyrylcholinesterase, acetylcholinesterase enzymes, and carbonic anhydrase I, and II isoforms. The novel 2-aminopyridine liganded (NHC)PdI₂(2-aminopyridine) complexes (1a-i) showed Ki values of in range of 5.78 ± 0.33-22.51 ± 8.59 nM against hCA I, 13.77 ± 2.21-30.81 ± 4.87 nM against hCA II, 0.44 ± 0.08-1.87 ± 0.11 nM against AChE and 3.25 ± 0.34-12.89 ± 4.77 nM against BChE. Additionally, we studied the inhibition effect of these derivatives on aldose reductase and α-glycosidase enzymes. For these compounds, compound 1d showed maximum inhibition effect against AR with a Ki value of 360.37 ± 55.82 nM. Finally, all compounds were tested for the inhibition of α-glycosidase enzyme, which recorded efficient inhibition profiles with Ki values in the range of 4.44 ± 0.65-12.67 ± 2.50 nM against α-glycosidase.

Identification of Ellagitannins in the Unripe Fruit of Rubus Chingii Hu and Evaluation of its Potential Antidiabetic Activity

As a functional food, the unripe fruits of Rubus chingii Hu have been widely used in China for thousands of years. Twenty-five major ellagitannins (ETs) were identified from the unripe fruits, and a novel ellagitannin, chingiitannin A (1), together with four other known ETs (2-5) were isolated and identified by HPLC-QTOF-MS/MS and 2D-NMR. Chingiitannin A showed the highest α-glucosidase and α-amylase inhibitory activities (IC₅₀ 2.89 and 4.52 μM, respectively), which occurred in a reversible and noncompetitive manner. Static quenching was indicated in a fluorescence quenching assay. Molecular docking results revealed that chingiitannin A interacted with the enzymes mainly by hydrogen bonding and was bound in the allosteric site. Chingiitannin A was nontoxic, and it increased the glucose uptake in L6 myotubes. The results suggested that the unripe fruits of Rubus chingii Hu are rich sources of ETs, and chingiitannin A might be a good candidate for functional foods or antidiabetic drugs.

Novel eugenol bearing oxypropanolamines: Synthesis, characterization, antibacterial, antidiabetic, and anticholinergic potentials

Five oxypropanol amine derivatives that four of them are novel have been synthesized with high yields and practical methods. in vitro antibacterial susceptibility of Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus strains to synthesized substances were evaluated with agar well-diffusion method by comparison with commercially available drugs. Most of the bacteria were multidrug resistant. It was concluded that these compounds are much more effective than reference drugs. These eugenol bearing oxypropanolamine derivatives were also effective inhibitors against α-glycosidase, cytosolic carbonic anhydrase I and II isoforms (hCA I and II), and acetylcholinesterase (AChE) enzymes with K_i values in the range of 0.80 ± 0.24-3.52 ± 1.01 µM for hCA I, 1.08 ± 0.15-3.64 ± 0.92 µM for hCA II, 5.18 ± 0.84-12.46 ± 2.08 µM for α-glycosidase, and 11.33 ± 2.83-32.81 ± 9.73 µM for AChE, respectively.

Dietary polyphenols modulate starch digestion and glycaemic level: a review

Polyphenols, as one group of secondary metabolite, are widely distributed in plants and have been reported to show various bioactivities in recent year. Starch digestion not only is related with food industrial applications such as brewing but also plays an important role in postprandial blood glucose level, and therefore insulin resistance. Many studies have shown that dietary phenolic extracts and pure polyphenols can retard starch digestion in vitro, and the retarding effect depends on the phenolic composition and molecular structure. Besides, dietary polyphenols have also been reported to alleviate elevation of blood glucose level after meal, indicating the inhibition of starch digestion in vivo. This review aims to analyze how dietary polyphenols affect starch digestion both in vitro and in vivo. We can conclude that the retarded starch digestion in vitro by polyphenols results from inhibition of key digestive enzymes, including α-amylase and α-glucosidase, as well as from interactions between polyphenols and starch. The alleviation of postprandial hyperglycemia by polyphenols might be caused by both the inhibited starch digestion in vivo and the influenced glucose transport. Therefore, phenolic extracts or pure polyphenols may be alternatives for preventing and treating type II diabetes disease.

Antidiabetic potential: In vitro inhibition effects of bromophenol and diarylmethanones derivatives on metabolic enzymes

Aldose reductase converts glucose to sorbitol in the polyol pathway. It is an important enzyme to prevent diabetic complications. In this study, we studied the inhibitory effects of bromophenol derivatives on aldose reductase (AR), α-glucosidase, and α-amylase enzymes. In the bromophenols series, compound 1f showed the maximum inhibition effect against AR with a K_i value of 0.05 ± 0.01 μM, while compound 1d showed the lowest inhibition effect against AR with a K_i value of 1.13 ± 0.99 μM. In addition, α-amylase from porcine pancreas and α-glucosidase from Saccharomyces cerevisiae were used as enzymes. In this study, all compounds were tested for the inhibition of the α-glucosidase enzyme and demonstrated efficient inhibition profiles with K_i values in the range of 43.62 ± 5.28 to 144.37 ± 16.37 nM against α-glucosidase. Additionally, these compounds were tested against the α-amylase enzyme, which determined an effective inhibition profile with IC₅₀ values in the range of 9.63-91.47 nM. These compounds can be selective inhibitors of AR, α-glucosidase, and α-amylase enzymes as antidiabetic agents.