Pancreatic Α-amylase Research Articles

161 The Effects of Feeding Hempseed Cake on Pancreatic and Intestinal Enzymatic Activity in Finishing Heifers

Abstract Due to the unique nature of the rumen, unlike monogastric animals, ruminants like cattle largely depend on microbial hydrolysis of feed rather than post-ruminal enzymatic degradation. However, in ruminants fed high-grain diets, significant amounts of starch can bypass ruminal fermentation, where pancreatic and small intestinal enzymes play a vital role in digestion. Ruminal microbiota, as well as the host animal, require protein as a nitrogen source to optimize digestibility. Hempseed cake (containing >30% of crude protein) is a by-product of hempseed oil production, but currently is not used as a feed source as it is not an FDA-approved feed ingredient. Presently, the availability and costs of protein supplements are volatile, and sourcing alternative protein sources is needed. Therefore, information is necessary on the effect of feeding hempseed cake on ruminant digestive function. This study aimed to evaluate the effects of feeding hempseed cake on pancreatic and intestinal enzymatic activity in finishing heifers. Angus-crossbred finishing heifers (494 ± 10 kg BW) were fed for 111 days with one of two dietary treatments: 20% [dry matter (DM) basis] of dried corn distillers grains plus solubles (n = 16, control) or hempseed cake (n = 16, hemp). All animals were slaughtered at the end of treatment. Intestinal tissues for digestive enzyme assays were isolated and stored at -800C following immediate flash freezing with liquid nitrogen. The MIXED procedure in SAS was used to analyze the data. There was a tendency (P = 0.09) of greater pancreatic tissue mass in the hemp group than in the control group. The activity of pancreatic α-amylase, trypsin, and lipase relative to protein (U/g protein) was less (P < 0.01) in heifers fed hemp than in heifers fed distillers grains primarily because protein concentration (mg/g) and content (g/pancreas) were greater (P < 0.01) in the hemp group than the control group. However, there were no differences (P ≥ 0.2) in digestive enzyme activity (U/g of tissue) in pancreatic and small intestinal tissues. Overall, our results suggest that there was no adverse effect of feeding hemp on the enzymes responsible for nutrient digestion in the small intestine and that hempseed cake may be useful as an alternative source of protein in cattle fed finishing diets.

α-Amylase and mycobacterium-TB H37Rv antagonistic efficacy of novel pyrazole-coumarin hybrids: an in vitro and in silico investigation

The present investigation of minutiae to acquire structural information of the novel pyrazole-coumarin hybrids (PC1-PC10) synthesized using ultrasound methods and characterized using different spectroscopic techniques: mass, 1H-NMR, 13 C-NMR and IR spectroscopy, and theoretically explored using the DFT approach with a B3LYP/6–311G (d, p) basis set, and there in vitro, antagonistic efficacy against α-amylase and mycobacterium-TB H37Rv are described in this article. Pyrazole-coumarin hybrids (PC1-PC10) showed α-amylase inhibition ranging from IC50 (0.32–0.58 mM) when compared with acarbose (IC50 = 0.34 mM). Similarly, Mycobacterium-TB H37Rv strain inhibition screening showed MIC values ranging from 62.5 to 1000 µg/mL when compared with rifampicin and isoniazid MIC = 0.25 and 0.20 µg/mL, respectively. Molecular docking and MD simulation studies were performed to determine the active sites and rationalize the activities of the active compounds. To investigate the binding conformation and dynamics responsible for their activity, the three most active compounds (PC1, PC3 and PC6) were docked into the porcine pancreatic α-amylase active site (PDB ID:1OSE), and mycobacterium-TB H37Rv active site (PDB ID: 4TZK). The binding interactions between PC1, PC3, and PC6 with α-amylase were like those responsible for inhibiting α-amylase by acarbose. Also, the mycobacterium-TB H37Rv inhibiting responsible residues were compared with standard isoniazid and rifampicin. Communicated by Ramaswamy H. Sarma

Phytochemical Profile, Antilipase, Hemoglobin Antiglycation, Antihyperglycemic, and Anti-Inflammatory Activities of Solanum elaeagnifolium Cav.

In the present investigation, the phenolic compounds of Solanum elaeagnifolium were identified, and the plant’s anti-lipase and anti-glycation effects on hemoglobin were discovered through in vitro experiments, as well as its short-term antihyperglycemic and anti-inflammatory effects. The chemical compound composition was detected using HPLC-DAD, the anti-lipase activity was tested in vitro using 4-nitrophenyl butyrate as a substrate, and the antiglycation activity of the plant extracts was also tested in vitro using a haemoglobin model. The antihyperglycemic effect was determined by inhibiting pancreatic α-amylase and α-glycosidase activity and performing an in vivo glucose tolerance test on normal rats, and the anti-inflammatory activity was determined by inducing paw inflammation with carrageenan. In both the SEFR (fruit) and SEFE (leaf) extracts, chromatographic analysis revealed the presence of quercetin 3-O-β-D-glucoside, rutin, and quercetin. SEFR inhibited the pancreatic lipase enzyme more effectively, with an IC50 of 0.106 ± 0.00 mg/mL. S. elaeagnifolium extracts demonstrated significant antiglycation activity, with 3.990 ± 0.23 mg/mL of SEFE and 3.997 ± 0.14 mg/mL of SEFR. When compared to positive and negative controls, plant extracts had very significant anti-diabetic and anti-inflammatory effects. The findings in this study and previous research on this plant encourage us to investigate other pharmacological activities of this plant besides its duiretic, cictrisant, and anti-ulcer activity.

Control of postprandial hyperglycemia by oral administration of the sea anemone mucus-derived α-amylase inhibitor (magnificamide)

Diabetes mellitus is a serious threat to human health in both developed and developing countries. Optimal disease control requires the use of a diet and a combination of several medications, including oral hypoglycemic agents such as α-glucosidase inhibitors. Currently, the arsenal of available drugs is insufficient, which determines the relevance of studying new potent α-amylase inhibitors. We implemented the recombinant production of sea anemone derived α-amylase inhibitor magnificamide in Escherichia coli. Peptide was isolated by a combination of liquid chromatography techniques. Its folding and molecular weight was proved by 1H NMR and mass spectrometry. The Ki value of magnificamide against human pancreatic α-amylase is 3.1 nM according to Morrison equation for tight binding inhibitors. Our study of the thermodynamic characteristics of binding of magnificamide to human salivary and pancreatic α-amylases by isothermal titration calorimetry showed the presence of different binding mechanisms with Kd equal to 0.11 µM and 0.1 nM, respectively. Experiments in mice with streptozotocin-induced diabetes mimicking diabetes mellitus type 1 were used to study the efficiency of magnificamide against postprandial hyperglycemia. It was found that at a dose of 0.005 mg kg–1, magnificamide effectively blocks starch breakdown and prevents the development of postprandial hyperglycemia in T1D mice. Our results demonstrated the therapeutic potential of magnificamide for the control of postprandial hyperglycemia.

Lavandula angustifolia mill. (Lamiaceae) ethanol extract and its main constituents as promising agents for the treatment of metabolic disorders: chemical profile, in vitro biological studies, and molecular docking

Lavandula angustifolia Mill. (lavender) is one of the most used medicinal plants. Herein, we chemically characterised and investigated the antioxidant properties and the capability to inhibit key enzymes for the treatment of type 2 diabetes (TD2) and obesity such as pancreatic lipase, α-glucosidase, and α-amylase of the ethanolic extract of two lavender samples (La1 and La2) from southern Italy. Both extracts significantly inhibited α-glucosidase, while La1 inhibited α-amylase and lipase more effectively than La2. To investigate whether these properties could be due to a direct interaction of the main constituents of the extracts with the targeted enzymes, molecular docking studies have been performed. As a result, the selected compounds were able to interact with the key residues of the binding site of the three proteins, thus supporting biological data. Current findings indicate the new potential of lavender ethanolic extract for the development of novel agents for T2D and obesity.

In Vitro Inhibitory Activities against α-Glucosidase, α-Amylase, and Pancreatic Lipase of Medicinal Plants Commonly Used in Chocó (Colombia) for Type 2 Diabetes and Obesity Treatment

Plant-based therapies are widely utilized for treating diseases in approximately 80% of the global population, including Colombia’s Chocó Department. This study aimed to identify and evaluate plants with significant therapeutic value for obesity and diabetes in Chocó. The inhibitory effects of these plants on pancreatic lipase (PL), α-glucosidase (AG), and α-amylase (AA) were assessed, and the most promising species were selected to isolate and identify bioactive components. Artocarpus altilis, Momordica balsamina, Bauhinia picta, Neurolaena lobata, and Vismia macrophylla emerged as key species based on their traditional usage among the Chocó population. Notably, the extract derived from Vismia macrophylla demonstrated the most encouraging outcomes as a digestive enzyme inhibitor, exhibiting IC50 values of 0.99 ± 0.21 μg/mL, 5.61 ± 0.82 mg/mL, and 28.91 ± 2.10 μg/mL for AG, AA, and PL, respectively. Further chemical analysis led to the isolation of three bioactive compounds: 5′-demethoxycadensin G 1, para-hydroxybenzoic acid methyl ester 2, and para-hydroxybenzoic acid butyl ester 3. Compound 1 displayed the highest activity against AG (IC50 = 164.30 ± 0.11 μM), while compounds 2 (IC50 = 28.50 ± 4.07 μM) and 3 (IC50 = 10.15 ± 3.42 μM) exhibited potent inhibitory effects on PL. Molecular docking and enzymatic kinetics studies indicate that these bioactive compounds primarily act as mixed inhibitors of AG and non-competitive inhibitors of PL. These findings underscore the potential of V. macrophylla and its compounds as effective inhibitors of digestive enzymes associated with obesity and type 2 diabetes.

The inhibition mechanism of bound polyphenols extracted from mung bean coat dietary fiber on porcine pancreatic α-amylase: kinetic, spectroscopic, differential scanning calorimetric and molecular docking

The inhibitory mechanisms of purified bound polyphenols extracted from mung bean coat dietary fiber (pMBDF-BP) on porcine pancreatic α-amylase (PPA) were investigated through inhibition kinetics, fluorescence spectroscopy, circular dichroism, differential scanning calorimetry and molecular docking. It was shown that pMBDF-BP exerted significant reversible inhibition on PPA in a mixed-type inhibition manner (IC50 = 18.57 ± 0.30 μg/mL), and the combination of the three major components exhibited a synergistic inhibitory effect on PPA. Further, pMBDF-BP bound to the active site or form a polyphenol-enzyme complex at the inactive site through hydrogen bonding and hydrophobic forces, via enhancing the hydrophobicity of the microenvironment surrounding tryptophan and tyrosine residues and promoting the secondary structure of PPA towards a more stable conformation, eventually reducing the enzyme activity. This study provided theoretical evidences for the utilization of bound polyphenols extracted from mung bean coat dietary fiber as a functional component in natural inhibitors of α-amylase.

Hypoglycemic activity of Syzygium cumini (L.) Skeels seed extracts: an approach to in vitro, in vivo, and in silico studies

This research is carried out to explore the hypoglycemic activity of Syzygium cumini seed extracts by in vitro, in vivo, and in silico methods. For in vitro studies the α-amylase and α-glucosidase enzyme inhibition assays were employed. For in vivo studies 30 alloxan induced Wistar rats were used. They were orally administered with glibenclamide and low/high dose of the extracts and were monitored regularly for the change in blood glucose levels for about 28 days. The in silico molecular docking was conducted to evaluate the binding interaction of 1,2,3-Benzenetriol with human pancreatic α-amylase and α-glucosidase. It was found that all the extracts were able to inhibit the α-amylase and α-glucosidase enzymes. Among which the acetone extract showed greater inhibition with 72.52 ± 0.51% and 63.02 ± 0.73% for both the enzymes, respectively. There was significant (p < 0.05) reduction in blood glucose levels in the rats administered with glibenclamide and extracts. In silico docking results revealed that the compound 1,2,3-Benzenetriol exhibited the highest binding affinity for human pancreatic α-amylase with binding energy −7.7 kcal/mol. Thus suggesting the utilization of S. cumini seeds in the management of diabetes mellitus. Communicated by Ramaswamy H. Sarma

Peculiarities of treatment of patients with comorbid pathology: chronic pancreatitis and hypothyroidism, taking into account SEPP1 gene polymorphism (RS7579)

Optimization of therapeutic regimens during the treatment of the polymorbid course of chronic pancreatitis combined with hypothyroidism is an important task of modern science.&#x0D; Aim: to treat patients with comorbid pathology: chronic pancreatitis and hypothyroidism, taking into account the polymorphism of the SEPP1 gene (RS7579)&#x0D; Materials and methods. During the research, we examined 128 people. Patients were divided into 3 groups. The first group included 48 patients with chronic pancreatitis, the second - 50 patients with chronic pancreatitis in combination with hypothyroidism, and the third - 30 practically healthy people.&#x0D; Results. Symptoms of maldigestion decreased in 72 % of the examined patients. Signs of nutritional deficiency have significantly decreased, and general well-being has improved. Multicomponent therapy also affected mood, sleep, and reduced irritability and symptoms of depression and anxiety disorders. A multisystemic polysyndromic approach to treatment led to improvements in both pancreatic and thyroid function. The effectiveness of the treatment strategy for patients with chronic pancreatitis was dependent on individual characteristics, such as the severity of chronic pancreatitis, the presence of primary hypothyroidism, the degree of selenium deficiency and concomitant symptoms, taking into account polymorphic variants of the SEPP1 (rs7579) gene. Selenoid deficiency decreased, especially in the group with a combination of chronic pancreatitis and hypothyroidism. The improvement in thyroid hormone activity included a 40.46 % decrease in blood TSH and a 2.5-fold increase in free T4.&#x0D; Conclusions. The program of complex therapy led to the normalization of the condition of patients with the G-allele genotype of the SEPP1 gene (rs7579), as evidenced by significant improvements in most of the analyzed indicators. The concentration of fecal elastase 1 and blood selenoprotein P significantly increased, and the level of serum pancreatic α-amylase significantly decreased in carriers of the AA genotype. Under the influence of therapy, there were also changes in the hormonal activity of the thyroid gland, a decrease in the concentration of total metabolites of NO, and an improvement in the health indicators of the cardiovascular system. However, for patients with the AA genotype of the SEPP1 (rs7579) gene, continuation of therapy remains important to achieve an optimal condition, in particular, to manage cholesterol levels and other cardiovascular risk factors

In silico docking studies of alpha-amylase inhibitors from the methanol extract of Aloe vera

In the current study, potent inhibitors of a-amylase, one of the significant regulating enzymes in diabetes, were identified from the methanolic extract of Aloe barbadensis miller (Aloe vera), an indigenous herbal plant used to treat carbohydrate absorption problems such as diabetes and obesity. The Aloe vera gel extract was dried, ground, macerated with methanol and subjected to phytochemical screening, which was characterized by gas chromatography. Since there is a rapid increase in computational methods to predict the association between two molecules, molecular docking studies assessed the effect of AVM (Aloe vera methanol) extract in inhibiting the enzyme alpha-amylase. The molecules derived from GC-MS analysis were employed as ligands for the receptor α-amylase in molecular docking experiments. The protein target used in this study was the human pancreatic α-amylase with PDB-ID -2QV4. The protein target and ligand structures were obtained from PDB and Pubchem databases respectively and docking studies were performed using PyRx. In this study, we intended to find distinct phytochemical substances from the Aloe vera plant as α-amylase inhibitors with an objective that the molecular docking studies provided in this study might result in the discovery of effective α-amylase inhibitors for diabetic management.

The genome of Anoplarchus purpurescens (Stichaeidae) reflects its carnivorous diet

Digestion is driven by digestive enzymes and digestive enzyme gene copy number can provide insights on the genomic underpinnings of dietary specialization. The “Adaptive Modulation Hypothesis” (AMH) proposes that digestive enzyme activity, which increases with increased gene copy number, should correlate with substrate quantity in the diet. To test the AMH and reveal some of the genetics of herbivory vs carnivory, we sequenced, assembled, and annotated the genome of Anoplarchus purpurescens, a carnivorous prickleback fish in the family Stichaeidae, and compared the gene copy number for key digestive enzymes to that of Cebidichthys violaceus, a herbivorous fish from the same family. A highly contiguous genome assembly of high quality (N50 = 10.6 Mb) was produced for A. purpurescens, using combined long-read and short-read technology, with an estimated 33,842 protein-coding genes. The digestive enzymes that we examined include pancreatic α-amylase, carboxyl ester lipase, alanyl aminopeptidase, trypsin, and chymotrypsin. Anoplarchus purpurescens had fewer copies of pancreatic α-amylase (carbohydrate digestion) than C. violaceus (1 vs. 3 copies). Moreover, A. purpurescens had one fewer copy of carboxyl ester lipase (plant lipid digestion) than C. violaceus (4 vs. 5). We observed an expansion in copy number for several protein digestion genes in A. purpurescens compared to C. violaceus, including trypsin (5 vs. 3) and total aminopeptidases (6 vs. 5). Collectively, these genomic differences coincide with measured digestive enzyme activities (phenotypes) in the two species and they support the AMH. Moreover, this genomic resource is now available to better understand fish biology and dietary specialization.

Pharmacognostical, Phytochemical, In vitro Anti-obesity Studies, and Toxicity Analysis of Momordica charantia Linnaeus Fruits from Haryana

Background: Momordica charantia Linnaeus (Cucurbitaceae family), known as bitter melon is an annual climbing vine, which grows in tropical regions and its fruits are consumed as a vegetable in Asian countries. Traditionally various parts of the plant such as fruits, seeds, leaves, flowers, etc. have been used for medicinal purposes. Its fruit is used as an anti-diabetic, laxative, anthelmintic, emetic, and anti-obesity, for respiratory problems, ulcers, wounds, rheumatism, gout, toothache, and skin diseases. Objective: To perform pharmacognostical evaluation, qualitative and quantitative phytochemical screening, safety and toxicity studies, and in vitro anti-obesity activity evaluation on bitter gourd fruits from Haryana (India). Methods: Organoleptic studies were performed with the naked eye and microscopical studies were performed using the EVOS microscope; physicochemical evaluation, microbial, and mycotoxin studies were performed by adopting the standard procedures detailed in the WHO guidelines (2011); phytochemical screening was performed by following the standard procedures; pesticide residue determination was performed by using GCMS; and in vitro anti-obesity evaluation consisting of in vitro pancreatic lipase, α-amylase, and α-glucosidase evaluation was performed by following the standard procedures. Results: The pharmacognostical standards i.e. macroscopy, microscopy, and physicochemical analyses of the fruits were established and their qualitative and quantitative phytochemical contents revealed the presence of alkaloids, glycosides, flavonoids, tannins, proteins, and amino acids, carbohydrates, fats, and fixed oils, sterols, and triterpenoids, etc. The fruit was found to be free from mycotoxin, microbial contamination, and harmful pesticide residues. The major pesticides found to be present in fruit extract were alpha-BHC, Aldrin, 4, 4’-DDE, Endrin, and4, 4'- DDD and they were present within permissible limits. The total phenolic content in the fruits was found to be 3.49 ± 1.3mg/g gallic acid equivalent/100g. The content of total flavonoids have been expressed as quercetin, catechin, and rutin equivalents, i.e., 1.88 ± 0.16, 122.7 ± 13.8 and 1.978 ± 0.006 mg/g dry weight of fruits respectively and they were present within permissible limits. The α-glucosidase inhibition potential of the alcoholic extract was good with an IC50 value of 173.50 ± 0.33 μg/ml, followed by aqueous extract i.e. 351.00 ± 0.56, whereas the chloroform extract showed milder inhibition with IC50 value of 448.60 ± 0.98 μg/ml. The lipase inhibition potential of aqueous extracts was good with an IC50 value of 140.31 ± 0.48μg/ml, followed by alcoholic extracts, with inhibition of 100.10 μg/ml, whereas the chloroform extracts show lesser inhibition, i.e., 499.83 μg/ml only. Whereas the alcoholic extract shows good α-amylase enzyme inhibition with IC50 value of 425.44 ± 0.63 μg/ml, followed by aqueous extract i.e., 486.12 ± 0.77 μg/ml, and chloroform extract shows lesser activity, i.e., 65. 82 ± 0.41 μg/ml. Conclusion: Identification and authentication of the fruits was performed with the help of pharmacognostical and physicochemical standards, and they could be useful for the monograph preparation of the plant and in controlling the commercial adulteration of the bitter gourd fruits. Safety and toxicity studies have determined that the fruits were fit for consumption. In vitro anti-obesity evaluation findings can be further explored in vivo for testing their therapeutic efficacy in lab animals. Proper identification of the crude drug helps the researchers in reproducing the results and carrying the research forward without wasting time that usually occurs due to misidentification of the crude drug which makes lab results difficult to reproduce.

Antihyperglycemic potential of the Lavandula stoechas aqueous extract via inhibition of digestive enzymes and reduction of intestinal glucose absorption

BackgroundDiabetes mellitus is a widespread metabolic disorder affecting global populations. Lavandula stoechas from Moroccan traditional medicine is used for its potential anti-diabetic effects. ObjectiveThis study aims to evaluate the antihyperglycemic impact of the aqueous extract of L. stoechas (AqLs) and explore its mechanisms. MethodsThe study employed a glucose tolerance test (OGTT) on normal and diabetic Wistar rats, administering AqLs at 150 mg/kg. In vitro, AqLs was tested against α-glucosidase and α-amylase activities, confirmed in vivo using normal and Allx-diabetic rats. The extract’s impact on intestinal d-glucose absorption was assessed using the jejunum segment perfusion technique at 250 mg/kg in situ. Albino mice were used to assess toxicity. ResultsAqLs significantly reduced postprandial hyperglycemia (P < 0.001) due to glucose overload. It inhibited pancreatic α-amylase (IC50: 0.485 mg/mL) and intestinal α-glucosidase (IC50: 168 µg/mL) in vitro. Oral AqLs at 150 mg/kg reduced hyperglycemia induced by sucrose and starch in normal and diabetic rats. It also lowered (P < 0.001) intestinal glucose absorption in situ at 250 mg/kg. Oral acute toxicity tests on Albino mice indicated no adverse effects at different doses. Conclusionto summarize, L. stoechas has evident antihyperglycemic effects attributed to inhibiting intestinal glucose absorption and key monosaccharide digestion enzymes like α-amylase and α-glucosidase.

Plant-Based Bioactive Phthalates Derived from Hibiscus rosa-sinensis: As In Vitro and In Silico Enzyme Inhibition.

Hibiscus rosa-sinensis is an attractive, ever-blossoming, and effortlessly available plant around the globe. The fabulous flowers of H. rosa-sinensis enjoy a significant status in folk medicine throughout the world and comprise a range of phyto constituents due to which this splendid flower owns numerous biological and pharmaceutical activities like antioxidant, antifungal, antimicrobial, anti-inflammatory, antipyretic, antidiabetic, and antifertility activity. Considering this, column chromatographic isolation of the phytoconstituents of ethyl acetate fraction of the flowers of H. rosa-sinensis was performed. A series of five phthalates including Di-n-octyl phthalate (HR1), ditridecyl phthalate (HR2), 1-allyl 2-ethyl phthalate (HR3), diethyl phthalate (HR4), and bis (6-methylheptyl) phthalate (HR5) were isolated. The structures of the isolated phthalates were elucidated by gas chromatography-mass spectrometry, 1H NMR, and 13C NMR. In silico and in vitro antidiabetic and antioxidant potential and DFT studies of isolated phthalates were carried out. In our study, isolated ligands were explored as potent antidiabetic as well as antioxidant agents as they exhibited good binding affinity (in in vitro and in silico experiments) against all selected protein targets. Compounds HR1-HR5 showed that the binding affinity value ranged from -5.9 to -5.2 kcal/mol, -5.5 to -4.3 kcal/mol, and -5.0 to -4.1 kcal/mol for target proteins 1HNY, 2I3Y, and 5O40, respectively. Among all isolated phthalates, HR5 can be a lead compound as it showed the best binding affinity with human pancreatic α-amylase (ΔG = -5.9 kcal/mol) and displayed a minimum inhibition concentration (IC50) of 11.69 μM among all phthalates. Compound HR1 was the best docked and scored compound for inhibiting glutathione peroxidase; however, HR2 possessed the lowest binding score of -5.0 kcal/mol, thus indicating the highest potential among isolated phthalates for inhibiting the superoxide dismutase. Furthermore, the top-ranked docked ligand-protein complex for each protein was assessed for stability of protein and complex mobility by molecular dynamics simulation using the IMOD server.

Insight into biological activities of chemically characterized extract from Marrubium vulgare L. in vitro, in vivo and in silico approaches.

Aqueous extracts of Marrubium vulgare L. (M. vulgare) are widely used in traditional medicine for their therapeutic effects. Hence, this study aims to evaluate in vitro, in vivo, and in silico the biological activities of M. vulgare aqueous extract to further support their traditional use. Qualitative phytochemical tests of M. vulgare extracts showed the presence of primary and secondary metabolites, while quantitative analyses recorded revealed the contents of total phenols, flavonoids, and tannins, with values of 488.432 ± 7.825mg/EAG gallic acid extract/g, 25.5326 ± 1.317mg/EQ Quercetin extract/g and 23.966 ± 0.187mg/EC catechin extract/g, respectively. Characterization of the phytochemical constituents of the extract revealed the presence of catechin and maleic acid as the most abundant while the evaluation of the antioxidant power revealed that the extract possesses significant antioxidant capacity, antimitotic potential, and antimicrobial properties against Streptococcus agalactiae and Staphylococcus epidermidis among many others. The antidiabetic activity of the extract showed a potent antihyperglycemic effect and a significant modulation of the pancreatic α-amylase activity as revealed by both in vitro and in vivo analysis, while an in silico evaluation showed that chemicals in the studied extract exhibited the aforementioned activities by targeting 1XO2 antimitotic protein, W93 antidiabetic protein and 1AJ6 antimicrobial protein, which revealed them as worthy of exploration in drug discovery odyssey. Conclusively, the result of this study demonstrates the numerous biological activities of M. vulgare and gives credence to their folkloric and traditional usage.

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.

Postruminal Casein Infusion and Exogenous Glucagon-Like Peptide 2 Administration Differentially Stimulate Pancreatic α-Amylase and Small Intestinal α-Glucosidase Activity in Cattle

BackgroundIncreasing luminal carbohydrate flow decreases pancreatic α-amylase activity but can increase jejunal maltase activity, suggesting that regulation of carbohydrase activity is perhaps uncoordinated in response to luminal carbohydrate flow. Increasing luminal casein flow increases pancreatic α-amylase activity in cattle, and exogenous glucagon-like peptide 2 (GLP-2) has been shown to increase small intestinal α-glucosidase activity in nonruminants. ObjectivesThe objective was to evaluate the effects of postruminal casein infusion, exogenous GLP-2, or their combination on endogenous pancreatic and small intestinal carbohydrase activity in cattle postruminally infused with starch. MethodsHolstein steers [n = 24; 250 ± 23 kg body weight (BW)] received a continuous abomasal infusion of 3.94 g raw corn starch/kg of BW combined with either 0 or 1.30 g casein/kg of BW. Steers received subcutaneous injections in 2 equal portions daily of excipient (0.5% bovine serum albumin) or 100 μg GLP-2/kg of BW per day. At the end of the 7-d treatment period, steers were slaughtered for tissue collection. Data were analyzed using the MIXED procedure of SAS version 9.4 (SAS Institute Inc.). ResultsPostruminal casein infusion increased (P ≤ 0.03) pancreatic mass by 12.6%, total pancreatic α-amylase activity by 50%, and postruminal starch disappearance from 96.7% to 99.3%. Exogenous GLP-2 increased (P < 0.01) total small intestinal and mucosal mass by 1.2 kg and 896 g, respectively. Relative to control, GLP-2 and casein + GLP-2 increased (P = 0.04) total small intestinal α-glucosidase activity by 83.5%. Total small intestinal maltase, isomaltase, and glucoamylase activity was 90%, 100%, and 66.7% greater for GLP-2 and casein + GLP-2 steers compared with control. ConclusionsCasein increased pancreatic α-amylase activity, GLP-2 increased small intestinal α-glucosidase activity, and the combination of casein and GLP-2 increased both pancreatic α-amylase activity and small intestinal α-glucosidase activity. This novel approach provides an in vivo model to evaluate effects of increasing endogenous carbohydrase activity on small intestinal starch digestion.

Phytochemical Analysis, Antioxidant, and Antihyperglycemic Activities of Crataegus monogyna Jacq Aqueous Extract

Objective This study aims to evaluate the phytochemical composition, antioxidant, and antihyperglycemic (in vivo, in vitro, and in silico) activities and acute toxicity of Crataegus monogyna Jacq ( C monogyna) aqueous extracts. Methods The study analyzed the aqueous extract of C monogyna through various methods such as phytochemical screening, and the high-performance liquid chromatography-ultraviolet (HPLC-UV)-visible analysis. The extract was also tested for antioxidant potential, acute toxicity, antihyperglycemic effect, and inhibitory effect on the pancreatic α-amylase enzyme. Additionally, the study used the molecular docking approach to identify the most potent ligands in the extract. Results The phytochemical screening of the aqueous extract of C monogyna showed the presence of flavonoids, tannins, coumarins, sterol, and triterpene. The extract was rich in total polyphenols (1.65 ± 0.04 mg gallic acid equivalent per gram of extract [GAE/g] DM), total flavonoids (0.33 ± 0.03 EQ/g DM), and condensed tannins (0.28 ± 0.01 EC/mg DM). HPLC-UV-visible analysis identified 9 phenolic compounds, with high levels of gallic acid and caffeic acid. The C monogyna extract has a high antioxidant activity with an IC50 of 9.23 ± 0.01 mg/mL by DPPH and 8.32 ± 0.02 mg/mL by FRAP. The aqueous extract of C monogyna was not toxic to albino mice. The glucose tolerance test showed a significant antihyperglycemic effect, with an IC50 of 0.070 ± 0.008 mg/mL for the inhibition of pancreatic α-amylase activity by the aqueous extract of C monogyna. The in vivo inhibitory effect of the extract on the pancreatic α-amylase enzyme was confirmed. Two flavonoids, catechin, and rutin, were identified as potent inhibitors of the activity of α-amylase in the in silico part of the study, compared to the native ligand, Acarbose. Conclusion The study found that C monogyna has significant antioxidant and antihyperglycemic properties. The presence of catechin and rutin may contribute to these effects. The results suggest that C monogyna could be used as a dietary supplement to prevent and treat diabetes.

Exploration of human pancreatic alpha-amylase inhibitors from Physalis peruviana for the treatment of type 2 diabetes

Type 2 Diabetes (T2D), a chronic metabolic disorder characterized by persistent hyperglycemia, accounts for ∼90% of all types of diabetes. Pancreatic α-amylase is a potential drug target for preventing postprandial hyperglycemia and inhibiting T2D in humans. Although many synthetic drugs have been identified against pancreatic α-amylase, however, reported several side effects, and plant-derived natural products are less explored against T2D. This study tested 34 flavonoids derived from the plant Physalis peruviana against the human pancreatic α-amylase (HPA) using in silico computational approaches such as molecular docking and molecular dynamics simulation approaches. Schrödinger, a drug discovery package with modules applicable for molecular docking, protein-ligand interaction analysis, molecular dynamics, post-dynamics simulation, and binding free energy calculation, was employed for all computational studies. Four flavonoids, namely, Chlorogenic acid, Withaperuvin F, Withaperuvin H, and Rutin, were picked based on their docking score ranging between −7.03 kcal/mol and −11.35 kcal/mol compared to the docking score −7.3 kcal/mol of reference ligand, i.e. Myricetin. The molecular dynamics analysis suggested that all flavonoids showed considerable stability within the protein’s catalytic pocket, except chlorogenic acid, which showed high deviation during the last 15 ns. However, the interactions observed in initial docking and extracted from the simulation trajectory involved > 90% identical residues, indicating the affinity and stability of the docked flavonoids with the protein. Therefore, all four compounds identified in this study are proposed as promising antidiabetic candidates and should be further considered for their in vitro and in vivo validation. Communicated by Ramaswamy H. Sarma

Physicochemical characterizations, α-amylase inhibitory activities and inhibitory mechanisms of five bacterial exopolysaccharides

Inhibiting pancreatic α-amylase activity can decrease the release rate of glucose, thereby delaying postprandial blood glucose. This study aimed to investigate the physicochemical properties and porcine pancreatic α-amylase (PPA) inhibitory activities of five bacterial exopolysaccharides (EPSs). We also aimed to analyze the differences of their inhibitory activities, exploring the inhibition mechanism between EPSs and PPA. Five EPSs had a low molecular weight (55–66 kDa), which were mainly composed of mannose and glucose with total content exceeding 86 %. The IC50 values of five EPSs (0.162–0.431 mg/mL) were significantly lower than that of acarbose (0.763 mg/mL), indicating that the inhibitory effects of five EPSs on PPA were stronger than acarbose, especially the EPS from Bacillus subtilis STB22 (BS–EPS). Moreover, BS–EPS was a mixed-type inhibitor, whereas other EPSs were noncompetitive inhibitors of PPA. Five EPSs quenched the fluorophore of PPA by the mixed quenching or apparent static quenching. Interestingly, BS–EPS showed stronger binding affinity to PPA than other EPSs. It can be speculated that EPSs with low molecular weight, high carboxylic acid content, and α-glycosidic bond exhibited high PPA inhibitory activity. These results suggest that BS-EPS can effectively inhibit PPA activity and has potential applications in reducing postprandial hyperglycemia.