The digestive enzymes-polyphenolic compounds (PCs) interactions behind the inhibition of these enzymes have not been completely studied. The existing studies have mainly analyzed polyphenolic ...extracts and reported inhibition percentages of catalytic activities determined by UV-Vis spectroscopy techniques. Recently, pure PCs and new methods such as isothermal titration calorimetry and circular dichroism have been applied to describe these interactions. The present review focuses on PCs structural characteristics behind the inhibition of digestive enzymes, and progress of the used methods. Some characteristics such as molecular weight, number and position of substitution, and glycosylation of flavonoids seem to be related to the inhibitory effect of PCs; also, this effect seems to be different for carbohydrate-hydrolyzing enzymes and proteases. The digestive enzyme-PCs molecular interactions have shown that non-covalent binding, mostly by van der Waals forces, hydrogen binding, hydrophobic binding, and other electrostatic forces regulate them. These interactions were mainly associated to non-competitive type inhibitions of the enzymatic activities. The present review emphasizes on the digestive enzymes such as α-glycosidase (AG), α-amylase (PA), lipase (PL), pepsin (PE), trypsin (TP), and chymotrypsin (CT). Existing studies conducted in vitro allow one to elucidate the characteristics of the structure-function relationships, where differences between the structures of PCs might be the reason for different in vivo effects.
Inhibition of target digestive enzymes is an accepted strategy to prevent diseases such as obesity and diabetes. Proanthocyanidins (PACs) are known for their ability to bind, inhibit, and precipitate ...enzymes, which makes them potential bioDrugs with an impact on the digestive process. PAC degree of polymerization (DP) is one of the structural features responsible for their differential inhibitory potency but the explanation for this phenomenon is still unclear. Pecan nut (Carya illinoinensis L.) kernels and nutshells are rich in oligomeric and polymeric PACs. We have used thiolysis and HPLC analyses to propose four theoretical model structures of PACs representative of four semipurified fractions obtained from pecan kernel and shell, which showed different inhibitory activity against intestinal lipases, amylases, and proteases. The noncovalent interactions between PACs and digestive enzymes were predicted by in silico methods through computational software. These observations are discussed in view of current literature on the biological effects of PACs with different DPs and allowed us to propose the hypothesis that “small oligomeric PACs could be digestive enzyme inhibitors due to their capacity to enter and bind the enzymes’ specific cavities better than polymers and oligomers of medium and high molecular weight.”
The inhibitory activity and binding characteristics of caffeic acid,
-coumaric acid, quercetin and capsaicin, four phenolic compounds found in hot pepper, against porcine pancreatic lipase activity ...were studied and compared to hot pepper extract. Quercetin was the strongest inhibitor (IC
=(6.1±2.4) µM), followed by
-coumaric acid ((170.2±20.6) µM) and caffeic acid ((401.5±32.1) µM), while capsaicin and a hot pepper extract had very low inhibitory activity. All polyphenolic compounds showed a mixed-type inhibition. Fluorescence spectroscopy studies showed that polyphenolic compounds had the ability to quench the intrinsic fluorescence of pancreatic lipase by a static mechanism. The sequence of Stern-Volmer constant was quercetin, followed by caffeic and
-coumaric acids. Molecular docking studies showed that caffeic acid, quercetin and
-coumaric acid bound near the active site, while capsaicin bound far away from the active site. Hydrogen bonds and π-stacking hydrophobic interactions are the main pancreatic lipase-polyphenolic compound interactions observed.
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•Elicited and non-elicited bean sprouts exerted a hypolipidemic effect mainly on TAG.•SA-elicited sprouts increased TAG excretion due to pancreatic lipase inhibition.•Hesperidin and ...soysaponin-I were identified as main hypotriglyceridemic compounds.•The elicitation did not improve the hypolipidemic effect of bean sprouts.
Common beans (Phaseolus vulgaris L.) are recommended as hypolipidemic adjuvants due to their high content of phytochemicals, which can be enhanced by germination and elicitation. The aim of this study was to evaluate the hypolipidemic effect of non-elicited control (CS) and chemically elicited 30 mM H2O2, 7 μM chitosan (CH), and 1 and 2 mM salicylic acid (SA) bean sprouts. Rats were fed with a high fat and fructose diet (HFF) and supplemented with bean sprouts (10%) for twelve weeks. Control- and elicited-common bean sprouts significantly (p < 0.05) decreased serum triacylglycerides (TAG). Sprouts elicited with 1 and 2 mM SA increased fecal TAG excretion, which was related to the inhibition of pancreatic lipase enzyme activity. Hesperidin and soysaponin-I were identified as the main hypotriglyceridemic phytochemicals of bean sprouts according to the chemometric and in silico analyses. Therefore, the hypotriglyceridemic effect of SA-elicited bean sprouts was associated with decreased TAG intestinal absorption.
Abstract Grape pomace (GP) and pecan shell (PS) are agro-industrial by-products rich in healthy bioactives, mainly phenolic compounds (PC) and dietary fiber (DF). Raw GP and PS were chemically ...characterized, and the adsorption isotherms of their PC-insoluble DF (IDF) complexes were evaluated. GP and PS statistically differed (p < 0.05) in chemical and physicochemical properties. Total PC, total flavonoids, and IDF were higher in GP. Thirteen and eight PC were identified in GP and PS by HPLC-MS/MS chromatography, finding isoquercetin and type B dimer and trimer procyanidins as the most abundant compounds. PC-IDF (phenolic compounds-insoluble dietary fiber) adsorption isotherms were determined by both spectroscopic (Freundlich) and HPLC-MS/MS (Freundlich/Langmuir) techniques, observing that PS IDF presented higher PC adsorption at all tested concentrations. Epicatechin, isoquercetin, and quercetin were the main identified PC in both by-products, and were able to fit to both Langmuir and Freundlich isotherm by HPLC-MS/MS.
Trypsin is a key protease related to digestion and absorption of proteins, which its inhibition must be studied when natural compounds, such as flavonoids, are used as part of alternative treatments ...for obesity and diabetes mellitus type 2, since trypsin and together with other pancreatic enzymes worked at small intestine. Considering that flavonoids are good lipase and amylase inhibitors, trypsin-flavonoids interactions were analyzed through UV-Vis, intrinsic and extrinsic fluorescence spectroscopies, circular dichroism, and molecular docking. The interaction between porcine pancreas trypsin and five flavonoids: hesperetin (HES), luteolin (LUT), quercetin (QUE), catechin (CAT), and rutin (RUT) was evaluated. Most of them exhibited a mixed-type mode. LUT was the best trypsin inhibitor (e.g., lower IC50, 45.20±1.00 µM). All flavonoids-trypsin complexes showed static quenching, and QUE and LUT exhibited higher affinity (higher Ka values, 0.90±0.10 and 1.60±0.20·10-1 mM-1, respectively). Hydrophobic interactions between trypsin and flavonoids were predominant.
Svrha je ovog istraživanja bila ispitati molekulsko uklapanje i inhibicijski učinak četiri fenolna spoja pronađena u ljutim papričicama, i to: kavene kiseline, p-kumarne kiseline, kvercetina i ...kapsaicina, na aktivnost lipaze izolirane iz svinjske gušterače. Najjači inhibicijski učinak imao je kvercetin (IC50=(6.1±2.4) μM), zatim p-kumarna (170.2±20.6) μM) i kavena kiselina (401.5±32.1) μM), dok su kapsaicin i ekstrakt ljute papričice imali iznimno slab učinak. Svi polifenolni spojevi imali su inhibicijski učinak miješanog tipa. Mjerenjem fluorescencije utvrđeno je da su polifenolni spojevi ugasili prirođenu fluorescenciju lipaze izolirane iz gušterače, i to pomoću statičkog mehanizma. Sekvencija Stern-Volmerove konstante bila je: kvercetin, kavena kiselina, te p-kumarna kiselina. Rezultati ispitivanja molekulskih uklapanja pokazali su da se kavena kiselina, kvercetin i p-kumarna kiselina vežu blizu, za razliku od kapsaicina koji se veže daleko od aktivnog mjesta. Vodikove veze i hidrofobne pi-interakcije glavni su načini međusobnog povezivanja polifenolnih spojeva u lipazi izoliranoj iz gušterače.
Evidence suggests that participation in physical activity may support young people's current and future mental health. Although previous reviews have examined the relationship between physical ...activity and a range of mental health outcomes in children and adolescents, due to the large increase in published studies there is a need for an update and quantitative synthesis of effects.
The objectives of this study were to determine the effect of physical activity interventions on mental health outcomes by conducting a systematic review and meta-analysis, and to systematically synthesize the observational evidence (both longitudinal and cross-sectional studies) regarding the associations between physical activity and sedentary behavior and mental health in preschoolers (2-5 years of age), children (6-11 years of age) and adolescents (12-18 years of age).
A systematic search of the PubMed and Web of Science electronic databases was performed from January 2013 to April 2018, by two independent researchers. Meta-analyses were performed to examine the effect of physical activity on mental health outcomes in randomized controlled trials (RCTs) and non-RCTs (i.e. quasi-experimental studies). A narrative synthesis of observational studies was conducted. Studies were included if they included physical activity or sedentary behavior data and at least one psychological ill-being (i.e. depression, anxiety, stress or negative affect) or psychological well-being (i.e. self-esteem, self-concept, self-efficacy, self-image, positive affect, optimism, happiness and satisfaction with life) outcome in preschoolers, children or adolescents.
A total of 114 original articles met all the eligibility criteria and were included in the review (4 RCTs, 14 non-RCTs, 28 prospective longitudinal studies and 68 cross-sectional studies). Of the 18 intervention studies, 12 (3 RCTs and 9 non-RCTs) were included in the meta-analysis. There was a small but significant overall effect of physical activity on mental health in children and adolescents aged 6-18 years (effect size 0.173, 95% confidence interval 0.106-0.239, p < 0.001, percentage of total variability attributed to between-study heterogeneity I
= 11.3%). When the analyses were performed separately for children and adolescents, the results were significant for adolescents but not for children. Longitudinal and cross-sectional studies demonstrated significant associations between physical activity and lower levels of psychological ill-being (i.e. depression, stress, negative affect, and total psychological distress) and greater psychological well-being (i.e. self-image, satisfaction with life and happiness, and psychological well-being). Furthermore, significant associations were found between greater amounts of sedentary behavior and both increased psychological ill-being (i.e. depression) and lower psychological well-being (i.e. satisfaction with life and happiness) in children and adolescents. Evidence on preschoolers was nearly non-existent.
Findings from the meta-analysis suggest that physical activity interventions can improve adolescents' mental health, but additional studies are needed to confirm the effects of physical activity on children's mental health. Findings from observational studies suggest that promoting physical activity and decreasing sedentary behavior might protect mental health in children and adolescents. PROSPERO Registration Number: CRD42017060373.
This study aimed to investigate the accuracy of a broad range of echocardiographic variables to develop multiparametric scores to diagnose CA in patients with proven light chain (AL) amyloidosis or ...those with increased heart wall thickness who had amyloid was suspected. We also aimed to further characterize the structural and functional changes associated with amyloid infiltration.
Cardiac amyloidosis (CA) is a serious but increasingly treatable cause of heart failure. Diagnosis is challenging and frequently unclear at echocardiography, which remains the most often used imaging tool.
We studied 1,187 consecutive patients evaluated at 3 referral centers for CA and analyzed morphological, functional, and strain-derived echocardiogram parameters with the aim of developing a score-based diagnostic algorithm. Cardiac amyloid burden was quantified by using extracellular volume measurements at cardiac magnetic resonance.
A total of 332 patients were diagnosed with AL amyloidosis and 339 patients with transthyretin CA. Concentric remodeling and strain-derived parameters displayed the best diagnostic performance. A multivariable logistic regression model incorporating relative wall thickness, E wave/e′ wave ratio, longitudinal strain, and tricuspid annular plane systolic excursion had the greatest diagnostic performance in AL amyloidosis (area under the curve: 0.90; 95% confidence interval: 0.87 to 0.92), whereas the addition of septal apical–to–base ratio yielded the best diagnostic accuracy in the increased heart wall thickness group (area under the curve: 0.80; 95% confidence interval: 0.85 to 0.90).
Specific functional and structural parameters characterize different burdens of CA deposition with different diagnostic performances and enable the definition of 2 scores that are sensitive and specific tools with which diagnose or exclude CA.
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