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1.
Food Chem ; 338: 128113, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33092009

RESUMO

Saponins are promising compounds for ameliorating hyperlipidemia but scarce information exists about sapogenins, the hydrolyzed forms of saponins. Saponin-rich extracts and their hydrolysates from fenugreek (FE, HFE) and quinoa (QE, HQE), and saponin and sapogenin standards, were assessed on the inhibition of pancreatic lipase and interference on the bioaccessibility of cholesterol by in vitro digestion models. All extracts inhibited pancreatic lipase (IC50 between 1.15 and 0.59 mg/mL), although the hydrolysis enhanced the bioactivity of HQE (p = 0.014). The IC50 value significantly correlated to the saponin content (r = -0.82; p = 0.001). Only the hydrolyzed extracts showed a reduction of bioaccessible cholesterol (p < 0.001) higher than that of phytosterols (35% reduction). Sapogenin standards exhibited no bioactivities, protodioscin and hederacoside C slightly inhibited the lipase (around 10%) and protodioscin reduced the bioaccessible cholesterol (23% reduction, p = 0.035). The hydrolysis process of saponin-rich extracts enhances the bioactivity and allows developing multibioactive products against pancreatic lipase and cholesterol absorption simultaneously.


Assuntos
Chenopodium quinoa/química , Lipase/antagonistas & inibidores , Pâncreas/enzimologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Saponinas/química , Trigonella/química , Anticolesterolemiantes/química , Anticolesterolemiantes/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Hidrólise
3.
J Food Sci ; 85(10): 3220-3228, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32895959

RESUMO

The leaves and fruits of Rhus coriaria are traditionally used in Turkey for the treatment of diabetes. The aim of the present study is to determine α-amylase, α-glucosidase, and pancreatic lipase inhibitory activities of R. coriaria leaf and fruit ethanol extracts (80%), and to isolate active compounds against these enzymes. As a result of the activity-guided isolation, the active compounds were determined as the amentoflavone, agathisflavone, and 1,2,3,4,6-penta-O-galloyl-ß-glucopyranose. Agathisflavone, amentoflavone, and penta-O-galloyl-ß-glucopyranose inhibited α-glucosidase with 11.4 ± 0.9, 11.3 ± 0.7, and 4.1 ± 0.1 µM IC50 values, respectively. Furthermore, penta-O-galloyl-ß-glucopyranose inhibited α-amylase with 6.32 ± 0.18 µM IC50 . These three compounds also significantly inhibited (P < 0.05) pancreatic lipase. The results of high-performance liquid chromatography analysis showed that penta-O-galloyl-ß-D-glycopyranose was one of the main compounds in both fruit and leaf extracts. Therefore, it may be considered that R. coriaria fruit and leaf extracts can be standardized on this substance and used in the development of both medicinal products and functional food for diabetes. PRACTICAL APPLICATION: Rhus coriaria (Sumac) is one of the plants that is well known and used around the world as a spice. It is also used against diabetes traditionally. The determination of effective compounds can lead to the standardization and development of both medicinal products and functional foods for diabetes. While the fruits of the plant are used as a spice all around the world, the leaves are generally throw away; therefore, the usage of the leaves to the food and medical industry can lead to beneficial effects on the economy.


Assuntos
Inibidores Enzimáticos/química , Lipase/antagonistas & inibidores , Extratos Vegetais/química , Rhus/química , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases/química , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/isolamento & purificação , Frutas/química , Humanos , Lipase/química , Pâncreas/enzimologia , Extratos Vegetais/isolamento & purificação , Turquia , alfa-Amilases/química
4.
Cochrane Database Syst Rev ; 8: CD008227, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32761612

RESUMO

BACKGROUND: Most people with cystic fibrosis (CF) (80% to 90%) need pancreatic enzyme replacement therapy (PERT) to prevent malnutrition. Enzyme preparations need to be taken whenever food is taken, and the dose needs to be adjusted according to the food consumed. A systematic review on the efficacy and safety of PERT is needed to guide clinical practice, as there is variability between centres with respect to assessment of pancreatic function, time of commencing treatment, dose and choice of supplements. This is an updated version of a published review. OBJECTIVES: To evaluate the efficacy and safety of PERT in children and adults with CF and to compare the efficacy and safety of different formulations of PERT and their appropriateness in different age groups. Also, to compare the effects of PERT in CF according to different diagnostic subgroups (e.g. different ages at introduction of therapy and different categories of pancreatic function). SEARCH METHODS: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Most recent search: 07 November 2019. We also searched an ongoing trials website and the websites of the pharmaceutical companies who manufacture pancreatic enzyme replacements for any additional trials. Most recent search: 26 December 2019. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials in people of any age, with CF and receiving PERT, at any dosage and in any formulation, for a period of not less than four weeks, compared to placebo or other PERT preparations. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trials and extracted outcome data. They also assessed the risk of bias and quality of the evidence (GRADE) of the trials included in the review. MAIN RESULTS: 14 trials were included in the review (641 children and adults with CF), two of these were parallel trials and 12 were cross-over trials. Interventions included different enteric and non-enteric-coated preparations of varying formulations in comparison to each other. The number of participants in each trial varied between 14 and 129. 13 trials were for a duration of four weeks and one trial lasted seven weeks. The majority of the trials had an unclear risk of bias from the randomisation process as the details of this were not given; they also had a high risk of attrition bias and reporting bias. The quality of the evidence ranged from moderate to very low. We mostly could not combine data from the trials as they compared different formulations and the findings from individual trials provided insufficient evidence to determine the size and precision of the effects of different formulations. AUTHORS' CONCLUSIONS: There is limited evidence of benefit from enteric-coated microspheres when compared to non-enteric coated pancreatic enzyme preparations up to one month. In the only comparison where we could combine any data, the fact that these were cross-over trials is likely to underestimate the level of inconsistency between the results of the trials due to over-inflation of CIs from the individual trials.There is no evidence on the long-term effectiveness and risks associated with PERT. There is also no evidence on the relative dosages of enzymes needed for people with different levels of severity of pancreatic insufficiency, optimum time to start treatment and variations based on differences in meals and meal sizes. There is a need for a properly designed trial that can answer these questions.


Assuntos
Fibrose Cística/terapia , Terapia de Reposição de Enzimas/normas , Dor Abdominal/epidemiologia , Adulto , Fatores Etários , Cápsulas/administração & dosagem , Criança , Preparações de Ação Retardada , Terapia de Reposição de Enzimas/efeitos adversos , Fármacos Gastrointestinais/uso terapêutico , Humanos , Microesferas , Estado Nutricional , Pâncreas/enzimologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Ganho de Peso
5.
Sci Rep ; 10(1): 11731, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678161

RESUMO

The digestive enzyme chymotrypsin protects the pancreas against pancreatitis by reducing harmful trypsin activity. Genetic deficiency in chymotrypsin increases pancreatitis risk in humans and pancreatitis severity in mice. Pancreatic chymotrypsin is produced in multiple isoforms including chymotrypsin B1, B2, C and chymotrypsin-like protease (CTRL). Here we investigated the role of CTRL in cerulein-induced pancreatitis in mice. Biochemical experiments with recombinant mouse enzymes demonstrated that CTRL cleaved trypsinogens and suppressed trypsin activation. We generated a novel CTRL-deficient strain (Ctrl-KO) using CRISPR-Cas9 genome engineering. Homozygous Ctrl-KO mice expressed no detectable CTRL protein in the pancreas. Remarkably, the total chymotrypsinogen content in Ctrl-KO mice was barely reduced indicating that CTRL is a low-abundance isoform. When given cerulein, Ctrl-KO mice exhibited lower intrapancreatic chymotrypsin activation and a trend for higher trypsin activation, compared with C57BL/6N mice. Despite the altered protease activation, severity of cerulein-induced acute pancreatitis was similar in Ctrl-KO and C57BL/6N mice. We conclude that CTRL is a minor chymotrypsin isoform that plays no significant role in cerulein-induced pancreatitis in mice.


Assuntos
Pâncreas/enzimologia , Pancreatite/etiologia , Pancreatite/metabolismo , Serina Endopeptidases/deficiência , Doença Aguda , Animais , Biópsia , Linhagem Celular , Quimotripsina/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , Expressão Gênica , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Pancreatite/patologia , Peroxidase/genética , Peroxidase/metabolismo , Índice de Gravidade de Doença , Tripsina/metabolismo
6.
Phys Chem Chem Phys ; 22(28): 16325-16333, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32648563

RESUMO

The use of cosolvents and high hydrostatic pressure (HHP) has been described as an efficient means to modulate the stability of enzymes and their catalytic activity. Cosolvents and pressure can lead to increased reaction rates without affecting the stability of the enzyme. Here, we studied the combined effects of one of the most used organic cosolvents, dimethyl sulfoxide (DMSO), and HHP to reveal their combined effect on the kinetic constants of an α-chymotrypsin-catalyzed peptide hydrolysis reaction. The Michaelis constant and the turnover number of the reaction respond differently to the two variables, and we observed an opposite effect of hydrostatic pressure and the dipolar cosolvent DMSO on the kinetic parameters. The results could be rationalized by determining the volume diagram of the reaction at the different solution conditions. In our case, the use of high hydrostatic pressure in concert with DMSO does not lead to an improvement of the enzymatic activity. However, the advantages of DMSO and HHP to increase the temperature stability of the enzyme and to increase the solubility of more hydrophobic substrates could still be useful.


Assuntos
Quimotripsina/metabolismo , Dimetil Sulfóxido/metabolismo , Animais , Biocatálise , Bovinos , Quimotripsina/química , Dimetil Sulfóxido/química , Hidrólise , Pressão Hidrostática , Cinética , Estrutura Molecular , Pâncreas/enzimologia , Termodinâmica
7.
Biochem Pharmacol ; 180: 114174, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32717227

RESUMO

Primary toxicity targets of alcohol and its metabolites in the pancreas are cellular energetics and endoplasmic reticulum (ER). Therefore, the role of AMP-Activated Protein Kinase (AMPKα) in amelioration of ethanol (EtOH)-induced pancreatic acinar cell injury including ER/oxidative stress, inflammatory responses, the formation of fatty acid ethyl esters (FAEEs) and mitochondrial bioenergetics were determined in human pancreatic acinar cells (hPACs) and AR42J cells incubated with/without AMPKα activator [5-aminoimidazole-4-carboxamide ribonucleotide (AICAR)]. EtOH treated hPACs showed concentration and time-dependent increases for FAEEs and inactivation of AMPKα, along with the upregulation of ACC1 and FAS (key lipogenic proteins) and downregulation of CPT1A (involved ß-oxidation of fatty acids). These cells also showed significant ER stress as evidenced by the increased expression for GRP78, IRE1α, and PERK/CHOP arm of unfolded protein response promoting apoptosis and activating p-JNK1/2 and p-ERK1/2 with increased secretion of cytokines. AR42J cells treated with EtOH showed increased oxidative stress, impaired mitochondrial biogenesis, and decreased ATP production rate. However, AMPKα activation by AICAR attenuated EtOH-induced ER/oxidative stress, lipogenesis, and inflammatory responses as well as the formation of FAEEs and restored mitochondrial function in hPACs as well as AR42J cells. Therefore, it is likely that EtOH-induced inactivation of AMPKα plays a crucial role in acinar cell injury leading to pancreatitis. Findings from this study also suggest that EtOH-induced inactivation of AMPKα is closely related to ER/oxidative stress and synthesis of FAEEs, as activation of AMPKα by AICAR attenuates formation of FAEEs, ER/oxidative stress and lipogenesis, and improves inflammatory responses and mitochondrial bioenergetics.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Células Acinares/enzimologia , Retículo Endoplasmático/enzimologia , Etanol/farmacologia , Estresse Oxidativo/fisiologia , Pâncreas/enzimologia , Células Acinares/efeitos dos fármacos , Aciltransferases/metabolismo , Adulto , Células Cultivadas , Relação Dose-Resposta a Droga , Retículo Endoplasmático/efeitos dos fármacos , Ácidos Graxos não Esterificados/metabolismo , Feminino , Humanos , Lipídeos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/citologia , Pâncreas/efeitos dos fármacos , Fenótipo
8.
Food Chem ; 326: 126785, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32438224

RESUMO

Obesity and oxidative damage are two important risk factors associated closely with metabolic syndrome. Utilization of functional food ingredients is considered as a feasible way to tackle these challenges. In the present study, eight representative species of citrus peel extracts (CPEs) were evaluated and compared for their flavonoid profiles, antioxidant activities, and pancreatic lipase (PL) inhibitory capacities and mechanisms. Results indicated that hesperidin, naringin, neohesperidin, narirutin and eriocitrin were the five major flavonoids in CPEs, among which hesperidin was the main active PL inhibitor. Moreover, hesperidin could interact with PL by hydrogen bonds and van der Waals forces, and the interaction would not obviously change the secondary structure of PL. Overall, ponkan peel extract, having the strongest overall antioxidant activity, the highest content of hesperidin and total phenolic compounds among all tested CPEs, is a promising natural ingredient to scavenge free radicals and manage obesity.


Assuntos
Antioxidantes/farmacologia , Citrus/química , Flavonoides/química , Lipase/metabolismo , Pâncreas/enzimologia , Extratos Vegetais/química , Animais , Fenóis/química , Suínos
9.
Am J Nurs ; 120(5): 58-62, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32332369

RESUMO

This is the seventh article in a new series about evidence-based practice (EBP) that builds on AJN's award-winning previous series-Evidence-Based Practice, Step by Step-published between 2009 and 2011 (to access the series, go to http://links.lww.com/AJN/A133). This follow-up series features exemplars illustrating the various strategies that can be used to implement EBP changes-one of the most challenging steps in the EBP process.


Assuntos
Fibrose Cística , Prática Clínica Baseada em Evidências , Adesão à Medicação , Pâncreas/enzimologia , Autogestão , Adolescente , Criança , Fibrose Cística/tratamento farmacológico , Fibrose Cística/enzimologia , Humanos , Inovação Organizacional , Participação dos Interessados , Inquéritos e Questionários , Ganho de Peso
10.
Biomed Res Int ; 2020: 3064290, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32258111

RESUMO

A full-length cDNA encoding digestive lipase (SmDL) was cloned from the pancreas of the smooth-hound (Mustelus mustelus). The obtained cDNA was 1350 bp long encoding 451 amino acids. The deduced amino acid sequence has high similarity with known pancreatic lipases. Catalytic triad and disulphide bond positions are also conserved. According to the established phylogeny, the SmDL was grouped with those of tuna and Sparidae lipases into one fish digestive lipase cluster. The recently purified enzyme shows no dependence for bile salts and colipase. For this, the residue-level interactions between lipase-colipase are yet to be clearly understood. The structural model of the SmDL was built, and several dissimilarities were noticed when analyzing the SmDL amino acids corresponding to those involved in HPL binding to colipase. Interestingly, the C-terminal domain of SmDL which holds the colipase shows a significant role for colipase interaction. This is apt to prevent the interaction between fish lipase and the pancreatic colipase which and can provide more explanation on the fact that the classical colipase is unable to activate the SmDL.


Assuntos
Colipases/genética , Elasmobrânquios/genética , Lipase/genética , Pâncreas/enzimologia , Sequência de Aminoácidos/genética , Aminoácidos/química , Aminoácidos/genética , Animais , Ácidos e Sais Biliares/genética , Domínio Catalítico/genética , Colipases/química , DNA Complementar/química , DNA Complementar/genética , Digestão/genética , Peixes/genética , Lipase/química , Pâncreas/química , Triglicerídeos/química , Triglicerídeos/genética
11.
J Colloid Interface Sci ; 573: 176-192, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32278949

RESUMO

Lipid cubic phase formulations have gained recognition as potential controlled delivery systems for a range of active pharmaceutical and biological agents on account of their desirable physiochemical properties and ability to encapsulate both hydrophobic and hydrophilic molecules. The most widely studied lipid cubic systems are those of the monoacylglycerol lipid family. These formulations are susceptible to lipolysis by a variety of enzymes, including lipases and esterases, which attack the ester bond present on the lipid chain bridging the oleic acid component to the glycerol backbone. The release of poorly soluble molecules residing in the lipid membrane portions of the phase is limited by the breakdown of the matrix; thus, presenting a potential means for further controlling and sustaining the release of therapeutic agents by targeting the matrix stability and its rate of degradation. The aims of the present study were twofold: to evaluate an approach to regulate the rate of degradation of lipid cubic phase drug delivery systems by targeting the enzyme interactions responsible for their demise; and to study the subsequent drug release profiles from bulk lipid cubic gels using model drugs of contrasting hydrophobicity. Here, hybrid materials consisting of cubic phases with monoacylglycerol lipids of different chain lengths formulated with a potent lipase inhibitor tetrahydrolipstatin were designed. Modulation of the release of a hydrophobic model pharmaceutical, a clofazimine salt, was obtained by exploiting the matrices' enzyme-driven digestion. A stable cubic phase is described, displaying controlled degradation with at least a 4-fold improvement compared to the blank systems shown in inhibitor-containing cubic systems. Sustained release of the model hydrophobic pharmaceutical was studied over 30 days to highlight the advantage of incorporating an inhibitor into the cubic network to achieve tunable lipid release systems. This is done without negatively affecting the structure of the matrix itself, as shown by comprehensive small-angle x-ray scattering experiments.


Assuntos
Inibidores Enzimáticos/farmacologia , Lipase/antagonistas & inibidores , Lipídeos/química , Orlistate/farmacologia , Animais , Liberação Controlada de Fármacos , Inibidores Enzimáticos/química , Interações Hidrofóbicas e Hidrofílicas , Lipase/metabolismo , Estrutura Molecular , Orlistate/química , Pâncreas/enzimologia , Suínos
12.
Clin Gastroenterol Hepatol ; 18(9): 2128-2130.e2, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32334082

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus that causes coronavirus disease 2019 (COVID-19) in human beings, has caused a serious public health issue.1 Attention to pancreatic injury is lacking, which may impact patients' prognosis. In this study, we explored the expression and distribution of angiotensin-converting enzyme 2 (ACE2), the receptor of SARS-CoV-2, in the pancreas. Combined with clinical data, we showed that pancreatic injury can occur in some COVID-19 patients.


Assuntos
Betacoronavirus/crescimento & desenvolvimento , Infecções por Coronavirus/complicações , Perfilação da Expressão Gênica , Pâncreas/enzimologia , Pancreatopatias/fisiopatologia , Peptidil Dipeptidase A/análise , Pneumonia Viral/complicações , Receptores Virais/análise , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Adulto Jovem
13.
Chem Biodivers ; 17(5): e2000010, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32196948

RESUMO

In the present study, non-thermal dielectric barrier discharge (DBD) plasma of induced structural changes of morin resulted in the isolation of one previously undescribed benzofuranone derivative, along with two known compounds. The chemical structures of these degradation products were elucidated by UV, NMR and FAB-MS spectroscopic analyses. The isolated three compounds showed potent antioxidative activities in two different tests, with IC50 values in the range of 12.9-41.8 µm in the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+ ) radical scavenging activity, 19.0-71.9 µm for hydroxyl radical scavenging activity test. Furthermore, the new methoxylated benzofuranone exhibited enhancement of inhibitory effects against pancreatic lipase with an IC50 value of 90.7±1.6 µm, when compared to the parent morin. These results suggested that the degradation products isolated from plasma exposed morin might be beneficial for prevention of obesity and related diseases.


Assuntos
Antioxidantes/farmacologia , Benzofuranos/farmacologia , Flavonoides/farmacologia , Antioxidantes/química , Antioxidantes/metabolismo , Benzofuranos/química , Benzofuranos/metabolismo , Benzotiazóis/antagonistas & inibidores , Biodegradação Ambiental , Impedância Elétrica , Flavonoides/química , Flavonoides/metabolismo , Humanos , Lipase/antagonistas & inibidores , Lipase/metabolismo , Estrutura Molecular , Pâncreas/enzimologia , Ácidos Sulfônicos/antagonistas & inibidores
14.
Ecotoxicol Environ Saf ; 192: 110305, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32070782

RESUMO

Environmental xenoestrogens are the most accessible endocrine disrupting chemicals that have been reported with harmful effects on human health. Although the influences of xenoestrogens on the endocrine system have been extensively studied, it remains unclear whether these xenoestrogens can affect the digestive system in mammals. This study aimed to investigate the inhibitory effects and the underlying mechanism of six non-steroidal synthetic estrogens (including hexestrol, diethylstilbestrol, dienestrol, bisphenol A, bisphenol AF and bisphenol Z) on pancreatic lipase (PL), a key digestive enzyme responsible for lipid digestion and absorption in mammals. The results clearly demonstrated that hexestrol, diethylstilbestrol and dienestrol exhibited strong inhibition on PL, with the IC50 values of less than 1.0 µM. Further investigations elucidated that these three synthetic estrogens functioned as mixed inhibitors of PL, with the Ki values of less than 1 µM. Moreover, molecular dynamics simulations showed that diethylstilbestrol and its analogues might block the binding of substrate on PL via occupying the portal to the active site of PL and thereby inhibit the hydrolytic activity of this key enzyme. Collectively, these results suggested that diethylstilbestrol and its analogues were potent PL inhibitors, which might play a profound role in lipid absorption and weight gain in mammals.


Assuntos
Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Inibidores Enzimáticos/toxicidade , Lipase/antagonistas & inibidores , Pâncreas/enzimologia , Animais , Domínio Catalítico , Estrogênios não Esteroides/toxicidade , Humanos , Lipase/química , Lipase/metabolismo , Xenobióticos
15.
Animal ; 14(S1): s17-s28, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32024574

RESUMO

Pregastric fermentation along with production practices that are dependent on high-energy diets means ruminants rely heavily on starch and protein assimilation for a substantial portion of their nutrient needs. While the majority of dietary starch may be fermented in the rumen, significant portions can flow to the small intestine. The initial phase of small intestinal digestion requires pancreatic α-amylase. Numerous nutritional factors have been shown to influence pancreatic α-amylase secretion with starch producing negative effects and casein, certain amino acids and dietary energy having positive effects. To date, manipulation of α-amylase secretion has not resulted in substantial changes in digestibility. The second phase of digestion involves the actions of the brush border enzymes sucrase-isomaltase and maltase-glucoamylase. Genetically, ruminants appear to possess these enzymes; however, the absence of measurable sucrase activity and limited adaptation with changes in diet suggests a reduced capacity for this phase of digestion. The final phase of carbohydrate assimilation is glucose transport. Ruminants possess Na+-dependent glucose transport that has been shown to be inducible. Because of the nature of pregastric fermentation, ruminants see a near constant flow of microbial protein to the small intestine. This results in a nutrient supply, which places a high priority on protein digestion and utilization. Comparatively, little research has been conducted describing protein assimilation. Enzymes and processes appear consistent with non-ruminants and are likely not limiting for efficient digestion of most feedstuffs. The mechanisms regulating the nutritional modulation of digestive function in the small intestine are complex and coordinated via the substrate, neural and hormonal effects in the small intestine, pancreas, peripheral tissues and the pituitary-hypothalamic axis. More research is needed in ruminants to help unravel the complexities by which small intestinal digestion is regulated with the aim of developing approaches to enhance and improve the efficiency of small intestinal digestion.


Assuntos
Aminoácidos/metabolismo , Carboidratos da Dieta/metabolismo , Ingestão de Energia , Proteínas/metabolismo , Ruminantes/metabolismo , Amido/metabolismo , Animais , Caseínas/metabolismo , Dieta/veterinária , Digestão , Fermentação , Intestino Delgado/metabolismo , Pâncreas/enzimologia , Rúmen/metabolismo , alfa-Amilases/metabolismo
16.
Carbohydr Polym ; 234: 115914, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32070532

RESUMO

In this work, ionic liquids-modified magnetic carboxymethyl cellulose nanoparticles (IL-MCMC) were prepared and used as supports for enzyme immobilization. The specific activity of immobilized lipase PPL-IL-MCMC was 1.43 and 2.81 folds higher than that of free PPL and PPL-MCMC, respectively. Water contact angle analysis indicated that the introduction of ionic liquids increased the hydrophobicity of supports, which in tune induced the lid-opening of lipase, allowing its active sites to become more accessible. In addition, the affinity between lipase and substrate immobilized on the prepared supports was enhanced. The same method was also applied to analyze immobilize penicillin G acylase (PGA) to further investigate the general applicability of the method. The results showed that the immobilized PGA exhibited higher stability than many other reported PGAs. The developed composites may be utilized as excellent supports for enzyme immobilization in industrial application.


Assuntos
Celulose/metabolismo , Líquidos Iônicos/metabolismo , Lipase/metabolismo , Nanopartículas de Magnetita/química , Animais , Biocatálise , Celulose/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Líquidos Iônicos/química , Lipase/química , Estrutura Molecular , Pâncreas/enzimologia , Tamanho da Partícula , Propriedades de Superfície , Suínos
17.
Anal Chim Acta ; 1099: 94-102, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-31986282

RESUMO

In terms of ligand fishing, the amount and the relative activity recovery of enzymes immobilized on magnetic particles and nanoparticles are not preeminent. Therefore, the metal-organic framework (MOF) UiO-66-NH2 was synthesized to immobilize the porcine pancreatic lipase (PPL) via precipitation-cross-linking, and the resulting novel biological matrices named PPL@MOF manifested high PPL loading capacity (98.31 mg/g) and relative activity recovery (104.4%). Moreover, the novel enzyme-MOF composite was applied to screen lipase inhibitors from Prunella vulgaris L. to enrich and improve the techniques of ligand fishing. As a result, 13 lipase ligands were obtained, and 12 compounds were determined by HPLC-Q-TOF-MS/MS. All of these ligands were further confirmed to be potential inhibitors through the verification of the activity assay and molecular docking. The proposed approach based on PPL@MOF was superior in terms of abundant protein loading capacity, high enzyme catalytic activity and easy preparation process. Taken together, our newly developed method provided a new platform for efficient discovering bioactive molecules from natural herbs.


Assuntos
Produtos Biológicos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Enzimas Imobilizadas/antagonistas & inibidores , Lipase/antagonistas & inibidores , Estruturas Metalorgânicas/farmacologia , Prunella/química , Animais , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Descoberta de Drogas , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Ligantes , Lipase/química , Lipase/metabolismo , Medicina Tradicional Chinesa , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/metabolismo , Simulação de Acoplamento Molecular , Pâncreas/enzimologia , Suínos
18.
Org Lett ; 22(4): 1380-1384, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-31999125

RESUMO

(±)-Melipatulinones A-C (1-3), three unique enantiomeric pairs of lignan-phloroglucinol hybrids along with the biogenetically related compound melipatulignan A (4), were isolated from the leaves of Melicope patulinervia. Melipatulinones A (1) and B (2) share a novel spiro[hydrobenzofuran-2,3'-furan] 5/5/6 tricyclic ring system, while melipatulinone C (3) features an unprecedented spiro[cyclopenta[b]hydrofuran-2,3'-furan] 5/5/5 tricyclic framework. Their structures were determined by spectroscopic methods, electronic circular dichroism (ECD) calculations, and X-ray diffraction. Compounds 1-3 exhibited a pancreatic lipase inhibitory effect.


Assuntos
Inibidores Enzimáticos/farmacologia , Lignanas/farmacologia , Lipase/antagonistas & inibidores , Rutaceae/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Lignanas/química , Lignanas/isolamento & purificação , Lipase/metabolismo , Conformação Molecular , Pâncreas/enzimologia , Folhas de Planta/química , Estereoisomerismo
19.
J Trace Elem Med Biol ; 58: 126448, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31901726

RESUMO

BACKGROUND: Increasing resistance to available drugs and their associated side-effects have drawn wide attention towards designing alternative therapeutic strategies for control of hyperglycemia and oxidative stress. The roles of the sizes and shapes of the nanomaterials used in the treatment and management of Type 2 Diabetes Mellitus (T2DM) in preventing chronic hyperglycaemia and oxidative stress are investigated. We report specifically on the effects of doping silver (Ag) into the ZnO nanorods (ZnO:Ag NR's) as a rational drug designing strategy. METHODS: Inhibition of porcine pancreatic α-amylase, murine pancreatic amylase, α-glucosidase, murine intestinal glucosidase and amyloglucosidase are checked for evaluation of antidiabetic potential. In addition, the radical scavenging activities of ZnO:Ag NR's against nitric oxide, DDPH and superoxide radicals are evaluated. RESULTS: Quantitative radical scavenging and metabolic enzyme inhibition activities of ZnO:Ag NR's at a concentration of 100 µg/mL were found to depend on the amount of Ag doped in up to a threshold level (3-4 %). Circular dichroism analysis revealed that the interaction of the NR's with the enzymes altered their secondary conformation. This alteration is the underlying mechanism for the potent enzyme inhibition. CONCLUSIONS: Enhanced inhibition of enzymes and scavenging of free radicals primarily responsible for reactive oxygen species (ROS) mediated damage, provide a strong scientific rationale for considering ZnO:Ag NR's as a candidate nanomedicine for controlling postprandial hyperglycaemia and the associated oxidative stress.


Assuntos
Antioxidantes/farmacologia , Hipoglicemiantes/farmacologia , Nanotubos/química , Prata/farmacologia , Óxido de Zinco/farmacologia , Amilases/antagonistas & inibidores , Amilases/metabolismo , Animais , Compostos de Bifenilo/química , Inibidores Enzimáticos/farmacologia , Depuradores de Radicais Livres/metabolismo , Inibidores de Glicosídeo Hidrolases/farmacologia , Intestinos/enzimologia , Camundongos , Nanotubos/ultraestrutura , Óxido Nítrico/metabolismo , Pâncreas/enzimologia , Picratos/química , Superóxidos/metabolismo , Suínos , alfa-Glucosidases/metabolismo
20.
Biosci Rep ; 40(1)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31919493

RESUMO

The kinetic aspects of lipolysis by pulmonary phospholipase A2 (ChPLA2-V), chicken intestinal phospholipase A2 (ChPLA2-IIA) and chicken pancreatic phospholipase A2 (ChPLA2-IB), from chicken have been compared using the monomolecular films technique, on short-chain phospholipids (with three different head groups) and on long-chain phospholipids. The main conclusions from our experimental data indicate that the maximum catalytic activities of ChPLA2-V on 1,2 phosphatidylcholine and 1,2 phosphatidylethanolamine reached 15.26 and 36.12 moles/cm2.min.mM, respectively, at a pressure of 15 and 35 dynes/cm, respectively. Whereas, those of ChPLA2-IB were 3.58 (at the pressure of 20 dynes/cm) and 4.9 moles/cm2.min.mM. However, hydrolysis of phosphatidylglycerol monolayers (C12PG), were very much higher compared with all the substrates tested with 122 moles/cm2.min. Surprisingly, the hydrolysis rate of ChPLA2-V on long-chain phosphatidylglycerol (C18PG) was very low (1.45 moles/cm2.min) compared with all tested substrates, even with the use of p-cyclodextrin. And thus, the fatty acid preference of ChPLA2-V was 2-decanoyl > 2-oleoyl with a PG head group. In order to gain significant correlations between enzyme's structures and their relative functions, we tried to examine the surface electrostatic potentials of the various secreted phospholipase 2 (sPLA2) from chicken. In the present study, we detailed that the substrate affinity, specificity and the hydrolysis rates of sPLA2 at each interface is governed by the surface electrostatic potentials and hydrophobic interactions operative at this surface.


Assuntos
Galinhas/metabolismo , Fosfolipases A2/metabolismo , Fosfolipídeos/metabolismo , Animais , Ácidos Graxos/metabolismo , Hidrólise , Intestinos/enzimologia , Cinética , Pâncreas/enzimologia , Pâncreas/metabolismo , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo
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