Kaempferol inhibits the activity of pancreatic lipase and its synergistic effect with orlistat

Fluorescence lifetime imaging of human pancreatic lipase activity using a novel probe for early diagnosis of severe acute pancreatitis

Severe Acute Pancreatitis, a serious condition caused by factors such as gallstones and chronic excessive alcohol consumption, with a very high mortality rate. Human pancreatic lipase (hPL) is a key digestive enzyme and abnormal activity levels of this enzyme are important indicators for diagnosing and monitoring pancreatic diseases. A fluorescent probe, LPP, has been developed to monitor the activity of hPL, especially in cases of SAP. The probe is based on cyanine isoindole derivatives, in vitro experiments confirmed the high specificity and sensitivity of the probe, with a detection limit of 0.012 U/mL, reactions completed within 10 min, and effective monitoring of pancreatic lipase activity in various biological samples. The stability and low cytotoxicity of LPP make it suitable for clinical applications, providing new tools and perspectives for the research and treatment of pancreatic diseases and related metabolic abnormalities. In addition, the change in fluorescence lifetime after the reaction of the probe with lipase allows for fluorescence lifetime imaging (FLIM), effectively monitoring the dynamic changes of hPL and enabling early diagnosis and monitoring of pancreatitis. This research not only enhances the understanding of pancreatic lipase activity detection but also has the potential to improve the diagnostics and treatment of pancreatitis.

Structural characterization of noni (Morinda citrifolia L.) pectin and its inhibitory activity on pancreatic lipase

This study aimed to investigate the physicochemical properties and biological activities of noni pectin (NP) extracted using various solvents, three fractions of noni pectin were obtained using traditional chemical and deep eutectic solvents. NPs are composed of various ratios of galacturonic acid, arabinose, rhamnose, xylose, glucose, and galactose with different yields, molecular weights, esterification degrees (DE), and microstructures. Among the fractions, noni pectin extracted with Betaine-citric acid (BNP) exhibited higher molecular weight, degree for esterification and pancreatic lipase (PL) inhibitory activity than the other fractions. Enzyme kinetic analysis indicated that BNP inhibited PL via a noncompetitive mechanism. BNP significantly altered the secondary structure of PL and quenched PL fluorescence, suggesting a static quenching mechanism. Isothermal titration calorimetry (ITC) further demonstrated that the binding of BNP to PL was spontaneous and driven by enthalpy, primarily mediated by hydrogen bonding and van der Waals forces. Molecular docking simulations also confirmed strong noncovalent interactions (hydrogen bonding and van der Waals forces) between BNP and PL. This study validated the high efficiency of the deep eutectic solvent-extracted noni pectin fraction in pancreatic lipase inhibition.

Structural characteristics of cell wall pectic polysaccharides from wampee and their decreased binding with pectinase by wampee polyphenol

To investigate the structural characteristics of cell wall pectic polysaccharides from wampee, water soluble pectin (WSP), chelator-soluble pectin (CSP) and sodium carbonate-soluble pectin (SSP) were purified. And the inhibitory effects of wampee polyphenol (WPP) on pectinase when these cell wall pectic polysaccharides were used as substrates were also explored. Purified WSP (namely PWSP) had the lowest molecular weight (8.47 × 105 Da) and the highest GalA content (33.43%). While purified CSP (called PCSP) and SSP contained more abundant rhamnogalacturonan I side chains. All of them were low-methoxy pectin (DE < 50%). Enzyme activity and kinetics analysis showed that the inhibition of pectinase by wampee polyphenol was reversible and mixed type. When SSP was used as the substrate, WPP had the strongest inhibition (IC50 = 1.96 ± 0.06 mg/mL) on pectinase. Fluorescence quenching results indicated that WPP inhibited enzyme activity by interacting with substrates and enzymes. Therefore, WPP has the application potential in controlling softening of fruits and vegetables.

Oral Administration of Kaempferol Isolated from Baccharis Mattogrosensis Enables In Vivo Activity Against Schistosoma Mansoni

Baccharis mattogrosensis is a species from Asteraceae which has been used in Brazilian folk medicine to treatment of several illnesses, including those caused by parasites. In the present work, the MeOH extract of aerial parts of B. mattogrosensis was subjected to chromatographic fractionation to afford three flavonoids: apigenin (1), quercetin (2), and kaempferol (3) as well as a mixture three chlorogenic acids: 3,4-O-dicaffeoylquinic (4), 3,5-O-dicaffeoylquinic (5), and 4,5-O-dicaffeoylquinic (6) acids. When tested in vitro, kaempferol (3) exhibited activity against Schistosoma mansoni with EC50=81.86 μM, whereas compounds 1, 2, 4-6 showed to be inactives. Considering this result, the effects of kaempferol (3) against S. mansoni infection using an experimental approach (in vivo assay) was tested at first time. Using a single oral dose (400 mg/kg) of kaempferol (3) to S. mansoni-infected mice reduced the worm burden by 25.5 %. Similarly, the number of eggs, which are responsible for a variety of pathologies and transmission of schistosomiasis, was decreased by 28.8 % in treated mice. Collectively, although kaempferol (3) is partially active when administered orally in a mouse model of schistosomiasis, our results suggest that this compound could be, in future studies, administered in different forms, such as nanoformulation.

The inhibitory activity of Flos Sophorae Immaturus extract and its major flavonoid components on pancreatic lipase

Inhibition of pancreatic lipase (PL) is a strategy to prevent obesity. The inhibitory effects of Flos Sophorae Immaturus (FSI) extract and its main flavonoid components, rutin and quercetin, on PL were investigated. The contents of rutin and quercetin in FSI extract were 44.10 ± 1.33 % and 6.07 ± 1.62 %, respectively. The IC50 values of FSI extract, rutin and quercetin on PL were 322, 258 and 71 μg/mL, respectively. Rutin and quercetin inhibited PL in a reversible and noncompetitive manner. The combination of rutin and quercetin exhibited synergistic inhibitory effects at low concentration. The binding of rutin/quercetin with PL caused the fluorescence quenching of protein. Fluorescence titration showed the binding affinity of quercetin with PL protein was stronger than that of rutin. Circular dichroism analysis showed the binding changed the secondary structure of PL with an increase in random coil and a decrease in α-Helix and β-Sheet. Molecular docking revealed that rutin and quercetin could interact with the amino acid residues around the catalytic site through multiple secondary interactions. In vivo studies showed that FSI extract can reduce fat absorption and promote fecal fat excretion through inhibition of PL activity, and the effects were mainly due to rutin and quercetin.

Morin inhibits the activity of pancreatic lipase and adipogenesis

Obesity is a major health issue that contributes significantly to increased mortality and morbidity worldwide. Obesity is caused by uncontrolled adipogenesis and lipogenesis, leading to several metabolism-associated problems. Pancreatic lipase, an enzyme that breaks down dietary lipids, is a prominent target for obesity. Orlistat, a known inhibitor of pancreatic lipase, is commonly employed for the management of obesity. However, its side effects, such as diarrhoea, nausea and bladder pain, urge to look out for safer alternatives. Morin is a pentahydroxyflavone, exerts a broad spectrum of pharmacological effects including antioxidant, anti-inflammatory, lipid lowering, anti-diabetic, anti-fibrotic, anti-cancer, etc. This study investigated the effect of morin on pancreatic lipase activity, in vitro and in vivo adipogenesis. Molecular docking and simulation studies showed morin to have a higher binding affinity towards pancreatic lipase compared with orlistat, which also inhibited its activity in vitro. Morin also reduced lipid droplet accretion and downregulated the expression of adipogenic and lipogenic genes. The acute oral toxicity of morin was determined in C57BL/6 mice, where morin did not show toxicity up to 2000 mg/kg body weight dose. Oral administration of morin to high fat diet fed mice reduced body weight, glucose and insulin levels. Also, the histopathological examination revealed reduction in adipocyte size and decreased mRNA expression of adipogenesis markers in white adipose tissue of morin administered group compared to high fat diet group. Overall, the results suggested morin inhibited pancreatic lipase activity, adipogenesis and further studies are warranted to explore its therapeutic potential for obesity.

Kinetic and thermodynamic-based studies on the interaction mechanism of novel R. roxburghii seed peptides against pancreatic lipase and cholesterol esterase

Pancreatic lipase (PL) and cholesterol esterase (CE) are vital digestive enzymes that regulate lipid digestion. Three bioactive peptides (LFCMH, RIPAGSPF, YFRPR), possessing enzyme inhibitory activities, were identified in the seed proteins of R. roxburghii. It is hypothesized that these peptides could inhibit the activities of these enzymes by binding to their active sites or altering their conformation. The results showed that LFCMH exhibited superior inhibitory activity against these enzymes compared to the other peptides. The inhibition mechanisms of the three peptides were identified as either competitive or mixed, according to inhibition models. Further studies have shown that peptides could bind to the active sites of enzymes, thus affecting their spatial conformation and restricting substrate entry into the active site. Molecular simulation further proved that hydrogen bonds and hydrophobic interactions played a vital role in the binding of peptides to enzymes. This study enriches our understanding of interaction mechanisms of peptides on PL and CE.

Inhibition of pancreatic lipase by coffee leaves-derived polyphenols: A mechanistic study

The suppression of pancreatic lipase has been employed to mitigate obesity. This study explored the mechanism of coffee leaf extracts to inhibit pancreatic lipase. The ethyl acetate fraction derived from coffee leaves (EAC) exhibited the highest inhibitory capacity with a half-maximal inhibitory concentration (IC50) of 0.469 mg/mL and an inhibitor constant (Ki) of 0.185 mg/mL. This fraction was enriched with 3,5-dicaffeoylquinic acid (3,5-diCQA, 146.50 mg/g), epicatechin (87.51 mg/g), and isoquercetin (48.29 mg/g). EAC inhibited lipase in a reversible and competitive manner, and quenched its intrinsic fluorescence through a static mechanism. Molecular docking revealed that bioactive compounds in EAC bind to key amino acid residues (HIS-263, PHE-77, and SER-152) located within the active cavity of lipase. Catechin derivatives play a key role in the lipase inhibitory activity within EAC. Overall, our findings highlight the promising potential of coffee leaf extract as a functional ingredient for alleviating obesity through inhibition of lipase.

A narrative review on the mechanism of natural flavonoids in improving glucolipid metabolism disorders

Glucolipid metabolism disorder (GLMD) is a complex chronic disease characterized by glucose and lipid metabolism disorders with a complex and diverse etiology and rapidly increasing incidence. Many studies have identified the role of flavonoids in ameliorating GLMD, with mechanisms related to peroxisome proliferator-activated receptors, nuclear factor kappa-B, AMP-activated protein kinase, nuclear factor (erythroid-derived 2)-like 2, glucose transporter type 4, and phosphatidylinositol-3-kinase/protein kinase B pathway. However, a comprehensive summary of the flavonoid effects on GLMD is lacking. This study reviewed the roles and mechanisms of natural flavonoids with different structures in the treatment of GLMD reported globally in the past 5 years and provides a reference for developing flavonoids as drugs for treating GLMD.

Evaluation of antioxidant, antidiabetic and antiobesity potential of phenylpropanoids (PPs): Structure-activity relationship and insight into action mechanisms against dual digestive enzymes by comprehensive technologies

Phenylpropanoids (PPs), a group of natural compounds characterized by one or more C6-C3 units, have exhibited considerable potential in addressing metabolic disease. However, the comprehensive investigation on the relationship of compound structures and involved activity, along with the action mechanisms on the drug target is absent. This study aimed to evaluate the antioxidant and inhibitory activities of 16 PPs against two digestive enzymes, including α-glucosidase and pancreatic lipase, explore the structure-activity relationships and elucidate the mechanisms underlying enzyme inhibition. The findings revealed the similarities in the rules governing antioxidant and enzyme inhibitory activities of PPs. Specifically, the introduction of hydroxyl groups generally exerted positive effects on the activities, while the further methoxylation and glycosylation were observed to be unfavorable. Among the studied PPs, esculetin exhibited the most potent antioxidant activity and dual enzymes inhibition potential, displaying IC50 values of 0.017 and 0.0428 mM for DPPH and ABTS radicals scavenging, as well as 1.36 and 6.67 mM for α-glucosidase and lipase inhibition, respectively. Quantification analysis indicated esculetin bound on both α-glucosidase and lipase successfully by a mixed-type mode. Further analyses by UV-Vis, FT-IR, fluorescence spectra, surface hydrophobicity, SEM, and molecular docking elucidated that esculetin could bind on the catalytic or non-catalytic sites of enzymes to form complex, impacting the normal spatial conformation for hydrolyzing the substrate, thus exhibiting the weakened activity. These results may shed light on the utilization value of natural PPs for the management of hyperglycemia and hyperlipemia, and afford the theoretical basis for designing drugs with stronger inhibition against the dual digestive enzymes based on esculetin.

Inquiry lipaseoring the mechanism of pancreatic lipase inhibition by isovitexin based on multispectral method and enzyme inhibition assay

Isovitexin is a main natural flavonoid component in various plants. Currently, the inhibitory effect of isovitexin on pancreatic lipase (PL) and its mechanism have not been elucidated yet. In the present study, we investigated the inhibitory effect of isovitexin on PL, as well as its interaction mechanism, using enzyme inhibition methods, spectroscopic analysis, and molecular simulations. Results showed that isovitexin possessed significant PL inhibitory activity, with IC50 values of 0.26 ± 0.02 mM. The interaction between isovitexin and PL was dominated by static quenching, and mainly through hydrogen bonding and hydrophobic interaction forces. Analysis of fluorescence spectroscopy confirmed that isovitexin binding altered the conformation of the PL. Circular dichroism (CD) spectrum indicated that isovitexin altered the secondary structure of PL by decreasing the α-helix content and increasing the β-fold content. Molecular simulations further characterize the conformational changes produced by the interaction between isovitexin with PL. The performed study may provide a new insight into the inhibitory mechanism of isovitexin as a novel PL inhibitor.

Kaempferol: Paving the path for advanced treatments in aging-related diseases

Aging-related diseases (ARDs) are a major global health concern, and the development of effective therapies is urgently needed. Kaempferol, a flavonoid found in several plants, has emerged as a promising candidate for ameliorating ARDs. This comprehensive review examines Kaempferol's chemical properties, safety profile, and pharmacokinetics, and highlights its potential therapeutic utility against ARDs. Kaempferol's therapeutic potential is underpinned by its distinctive chemical structure, which confers antioxidative and anti-inflammatory properties. Kaempferol counteracts reactive oxygen species (ROS) and modulates crucial cellular pathways, thereby combating oxidative stress and inflammation, hallmarks of ARDs. Kaempferol's low toxicity and wide safety margins, as demonstrated by preclinical and clinical studies, further substantiate its therapeutic potential. Compelling evidence supports Kaempferol's substantial potential in addressing ARDs through several mechanisms, notably anti-inflammatory, antioxidant, and anti-apoptotic actions. Kaempferol exhibits a versatile neuroprotective effect by modulating various proinflammatory signaling pathways, including NF-kB, p38MAPK, AKT, and the β-catenin cascade. Additionally, it hinders the formation and aggregation of beta-amyloid protein and regulates brain-derived neurotrophic factors. In terms of its anticancer potential, kaempferol acts through diverse pathways, inducing apoptosis, arresting the cell cycle at the G2/M phase, suppressing epithelial-mesenchymal transition (EMT)-related markers, and affecting the phosphoinositide 3-kinase/protein kinase B signaling pathways. Subsequent studies should focus on refining dosage regimens, exploring innovative delivery systems, and conducting comprehensive clinical trials to translate these findings into effective therapeutic applications.

Natural compounds as obesity pharmacotherapies

Obesity has become a serious global public health problem, affecting over 988 million people worldwide. Nevertheless, current pharmacotherapies have proven inadequate. Natural compounds have garnered significant attention due to their potential antiobesity effects. Over the past three decades, ca. 50 natural compounds have been evaluated for the preventive and/or therapeutic effects on obesity in animals and humans. However, variations in the antiobesity efficacies among these natural compounds have been substantial, owing to differences in experimental designs, including variations in animal models, dosages, treatment durations, and administration methods. The feasibility of employing these natural compounds as pharmacotherapies for obesity remained uncertain. In this review, we systematically summarized the antiobesity efficacy and mechanisms of action of each natural compound in animal models. This comprehensive review furnishes valuable insights for the development of antiobesity medications based on natural compounds.

Molecular Docking Studies and In Vitro Activity of Paliurus spina-christi Mill Extracts as Pancreatic Lipase Inhibitors

Obesity is a risk factor for the onset of chronic diseases. One of the most promising approaches to treating obesity consists of reducing dietary fat absorption using extracts from plants because they contain phenolic compounds, especially flavonoids. Paliurus spina-christi, belonging to the Rhamnaceae family, is one of the five species belonging to the Paliurus genus. Herein, the aerial parts of the plant were extracted with methanol through the pressurized cyclic solid-liquid extraction using the Naviglio extractor®. The extracts were analyzed with High Performance Thin Layer Chromatography and investigated for their in vitro biological potential. The phytochemical analysis revealed that rutin has been shown to be the most abundant flavonoid component. The best antiradical activity was observed for the fruit extract with an IC50 value of 53.41 ± 1.24 µg/mL. This extract also has a better inhibitory capacity on lipid peroxidation evaluated at a different time of incubation. Potent lipase inhibitor activity of the extract from fruits was also demonstrated with in vitro experiments. This property can be attributed to a direct interaction of main components of P. spina-christi extract with the human pancreatic enzyme as demonstrated by the results of molecular docking experiments conducted on the crystallographic structures of lipase.

Inhibition of Pancreatic Lipase by Flavonoid Derivatives: In Vitro and In Silico Investigations

Obesity, characterized by excessive adipose tissue accumulation, has emerged as a crucial determinant for a wide range of chronic medical conditions. The identification of effective interventions for obesity is of utmost importance. Widely researched antiobesity agents focus on pancreatic lipase, a significant therapeutic target. This study presented the evaluation of ten flavonoid compounds in terms of their inhibitory activities against pancreatic lipase, utilizing both in vitro and in silico approaches. The results indicated that all tested compounds demonstrated modest and weaker inhibitory activities compared to the reference compound, orlistat. Among the compounds investigated, F01 exhibited the highest potency, with an IC50 value of 17.68 ± 1.43 µM. The enzymatic inhibition kinetic analysis revealed that F01 operated through a competitive inhibition mechanism with a determined Ki of 7.16 μM. This value suggested a moderate binding affinity for the pancreatic lipase enzyme. Furthermore, the associated Vmax value was quantified at 0.03272 ΔA·min-1. In silico studies revealed that F01 displayed a binding mode similar to that of orlistat, despite lacking an active functional group capable of forming a covalent bond with Ser152 of the catalytic triad. However, F01 formed a hydrogen bond with this crucial amino acid. Furthermore, F01 interacted with other significant residues at the enzyme's active site, particularly those within the lid domain. Based on these findings, F01 demonstrates substantial potential as a candidate for further investigations.

Soluble polysaccharides decrease inhibitory activity of banana condensed tannins against porcine pancreatic lipase

The inhibition of soluble polysaccharides (SPs) (arabic gum, dextran and pectin from citrus) on the binding between banana condensed tannins (BCTs) and pancreatic lipase (PL) was studied from variant aspects. Molecular docking simulations predicted that BCTs strongly bound SPs and PL through non-covalent interactions. The experimental results showed that SPs reduced the inhibition of BCTs on PL, and the IC₅₀ value increased. However, the addition of SPs did not change the inhibitory type of BCTs on PL, which all were non-competitive inhibition. BCTs quenched PL fluorescence through static quenching mechanism and changed the secondary structure of PL. The addition of SPs alleviated the trending. The effect of SPs on the binding of BCTs-PL was mainly due to the strong non-covalent interaction between SPs and BCTs. This study emphasized that attention should be paid to the counteracting effects of polysaccharides and polyphenols in dietary intake to maximize their respective roles.

Hyperoside inhibits pancreatic lipase activity in vitro and reduces fat accumulation in vivo

Hyperoside, the main component of many anti-obesity plants, might exhibit a lipase inhibition effect to reduce fat accumulation. The anti-obesity effect of hyperoside was investigated by studying its inhibitory effect and mechanism on pancreatic lipase in vitro and evaluating its ability to reduce lipid accumulation in vivo. Hyperoside is a mixed-type inhibitor of lipase with an IC₅₀ of 0.67 ± 0.02 mmol L^-in vitro. Hyperoside changed the secondary conformation of lipase, increased the α-helix content, and changed the microenvironment of lipase through static quenching. The interaction between hyperoside and lipase results from a strong binding spontaneous exothermic reaction, mainly through hydrogen bonding, van der Waals force and electrostatic force. Hyperoside protected hepatic lipid accumulation and adipose tissue hypertrophy and reduced the expression of inflammatory factors in high-fat diet-induced rats. Moreover, hyperoside had a good inhibitory effect on lipase activity in serum and increased fecal fat excretion, thereby reducing lipid absorption in vivo. This study provides theoretical support for the research and development of hyperoside in fat-reducing functional foods.

Screening and identification of lipase inhibitors extracted from Dioscorea nipponica Makino by UV-vis and HPLC coupled to UPLC-Q-TOF-MS/MS

Dioscoreae nipponica Makino (D. nipponica) as the rhizome of dioscoreaceae rich in steroidal saponins, has been reported to have the hypolipidemic effects etc. However, it is still unclear which exact active components are primary responsible for the beneficial effects. This study was conducted to fish out the lipase inhibitors from D. nipponica, and evaluate the inhibitory activity on porcine pancreatic lipase (PPL) through in vitro kinetic assay using p-nitrophenyl palmitate as substrate. Accordingly, the ethanolic extract was subjected to D101 macroporous resin purification for spectrophotometric screening, high performance liquid chromatography (HPLC) separation and structural characterization by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. Through orlistat validation, the PPL inhibitory activity and IC₅₀ value of the extract were respectively 68.34 ± 1.47 % and 107.05 μg/mL under the optimized inhibition conditions. From 6 steroidal saponins identified, the inhibitory components named the protodioscin, protogracillin, dioscin and gracillin were fished out by grouping separation and HPLC analysis. Furthermore, dioscin and gracillin with the parent structure of diogenin were confirmed as the major inhibitors by virtue of stability tests based on transformation of protodioscin and protogracillin. Finally, the inhibitory mechanism of the major inhibitors toward PPL was further clarified by kinetic analysis and molecular docking analysis. The proposed method not only revealed the PPL inhibitory components in D. nipponica, but also provided an effective approach to hierarchical screening of PPL inhibitors from natural plants.

Nutrients, Phytochemicals and In Vitro Disease Prevention of Nephelium hypoleucum Kurz Fruit

Nephelium hypoleucum Kurz is an evergreen tree in the Sapindaceae family, mostly found in the forests of some Southeast Asia countries, especially Thailand. The lack of biological information regarding this tree has led to inappropriate agricultural management, conservation and utilization. Thus, this study aims to examine the nutritional composition, organic acid and phenolic profiles and in vitro health properties through several key enzyme inhibitions against some civilization diseases including Alzheimer's disease (β-secretase (BACE-1), butyrylcholinesterase (BChE) and acetylcholinesterase (AChE)), obesity (lipase), hypertension (angiotensin-converting enzyme (ACE)) and diabetes (dipeptidyl peptidase-IV (DPP-IV), α-amylase and α-glucosidase) on the aril (flesh) part of N. hypoleucum Kurz fruit. The remaining fruit parts including the pericarp (peel) and seed were also assessed as sources of potential phenolics as well as key enzyme inhibitors. As results, carbohydrate (17.18 g) was found to be a major source of energy (74.80 kcal) in the aril (100 g fresh weight), with trace amounts of protein (0.78 g) and fat (0.32 g). The fruit aril also contained high insoluble dietary fiber (5.02 g) and vitamin C (11.56 mg), while potassium (215.82 mg) was detected as the major mineral. Organic acid profile indicated that the aril was rich in citric acid, while the phenolic profile suggested predominant quercetin and kaempferol. Interestingly, high gallic acid contents were detected in both pericarp and seed, with the latter 3.2-fold higher than the former. The seed also possessed the highest total phenolic content (TPC, 149.45 mg gallic acid equivalent/g dry weight), while total anthocyanin content (TAC, 0.21 mg cyanidin-3-O-glucoside equivalent/g dry weight) was only detected in pericarp. High TPC also led to high enzyme inhibitory activities in seed including BACE-1, AChE, BChE, ACE, DPP-IV and α-glucosidase. Interestingly, aril with the highest α-amylase inhibition suggested strong inhibitory distribution, predominantly from quercetin and kaempferol. Lipase inhibitory activities were only detected in the aril and pericarp, suggesting the biological function of these two phenolics and possibly anthocyanins.

Antiobesity potential of major metabolites from Clitoria ternatea kombucha: Untargeted metabolomic profiling and molecular docking simulations

The prevalence of obesity is rapidly increasing and poses serious health risks accompanied by a decrease in life expectancy and quality of life. Therefore, the therapeutic potential of natural-derived nutraceuticals against obesity and its comorbidities needs to be explored. Molecular inhibition of lipase enzymes and fat mass and obesity-associated (FTO) protein has attracted some recent interest in efforts to find antiobesity agents. This study aims to innovate a fermented drink from Clitoria ternatea kombucha (CTK), find out their metabolites profile, and determine the antiobesity potential through a molecular docking study. The CTK formulation refers to previous research while the metabolites profile was determined using HPLC-ESI-HRMS/MS. Major compounds were selected based on best match value > 99.0% of the M/Z cloud database. A total of 79 compounds were identified in CTK, and 13 ideal compounds were selected to be simulated in the molecular docking study against human pancreatic lipase, α-amylase, α-glucosidase, porcine pancreatic lipase, and FTO proteins. The study found that Kaempferol, Quercetin-3β-D-glucoside, Quercetin, Dibenzylamine, and α-Pyrrolidinopropiophenone showed the best potential as functional antiobesity compounds since their affinity value ranked high in each respective receptor. In conclusion, the major compounds of CTK metabolites have the potential to be promising functional foods against obesity. However, further in vitro and in vivo studies should validate these health benefits.

Anti-pancreatic lipase and anti-adipogenic effects of 5, 7, 3',4',5' -pentamethoxy and 6, 2',4'-trimethoxy flavone - An In vitro study

In this study, the anti-obesity effects of 5,7,3',4',5-pentamethoxyflavone (PMF) and 6,2',4'-trimethoxyflavone (TMF) were evaluated through two distinct mechanisms of action: inhibition of crude porcine pancreatic lipase (PL), and inhibition of adipogenesis in 3T3-L1 pre-adipocytes. Both flavones show dose dependent, competitive inhibition of PL activity. Molecular docking studies revealed binding of the flavones to the active site of PL. In 3T3-L1 adipocytes, both flavones reduced the accumulation of lipids and triglycerides. PMF and TMF also lowered the expression of adipogenic and lipogenic genes. They both reduced the expression of peroxisome proliferator-activated receptor-gamma (PPAR-γ), CCAAT/enhancer-binding protein α and β (C/EBP α and β), sterol regulatory element-binding protein 1 (SREBF 1), fatty acid synthase (FASN), adipocyte binding protein 2 (aP2), and leptin gene. In addition, these flavones enhanced adiponectin mRNA expression, increased lipolysis and enhanced the expression of lipolytic genes: adipose triglycerides lipase (ATGL), hormone sensitive lipase (HSL) and monoglycerides lipase (MAGL) in mature 3T3-L1 adipocytes. Overall, PMF was seen to be a more potent inhibitor of both PL activity and adipogenesis versus TMF. These results suggest that PMF and TMF possess anti-obesity activities and can be further evaluated for their anti-obesity effects.

Design and Synthesis of Echitamine-inspired Hybrid Analogues Containing Thiazolidinediones as Potential Pancreatic Lipase Inhibitors

Background:

Obesity is a multifactorial metabolic disease characterised by excessive accumulation of triglycerides. The prevalence and morbidity rates associated with obesity are increasing tremendously, posing a significant risk to society. Pancreatic lipase (PL) is a key enzyme responsible for the digestion of dietary triglycerides; hence its inhibition is considered an attractive target in obesity.

Methods:

In this present work, a new series of echitamine-inspired indole-based thiazolidinedione hybrid analogues were designed, synthesized, and evaluated for their in vitro PL inhibitory potential. The nature of inhibition has been identified by enzyme kinetic analysis, whereas in silico molecular modelling tools (molecular docking and dynamic studies) were used for the identification of the mode of action at the catalytic site of PL (PDB ID: 1LPB). Fluorescence quenching was used for the identification of the interaction between the potent analogues with PL.

Results:

The condensation reaction of substituted indole derivatives with TZD in the presence of aqueous KOH resulted in the formation of the titled analogues. Analogues 7k and 7p displayed a potential PL inhibitory activity (IC50 = 11.36 and 11.87 μM, respectively). A competitive mode of PL inhibition was revealed in the enzyme kinetic analysis. A static quenching mechanism was exhibited by the screened agents on PL. The obtained MolDock scores were aligned with the in vitro PL inhibitory activity (Pearson’s r - 0.7575, p<0.05). Moreover, the PL-ligand complexes were stable in the dynamic conditions.

Conclusion:

Analogue 7k exerted the potential activity, and further studies might result in novel lead molecules.

LC-HRMS-Based Profiling: Antibacterial and Lipase Inhibitory Activities of Some Medicinal Plants for the Remedy of Obesity

Globally, obesity is a serious health concern that causes numerous diseases, including type 2 diabetes, hypertension, cardiovascular diseases, etc. Medicinal plants have been used to aid in weight loss since ancient times. Thus, this research is focused on the exploration of pancreatic lipase inhibitory activity and secondary metabolite profiling of Bergenia ciliata, Mimosa pudica, and Phyllanthus emblica, selected based on an ethnobotanical survey. The lipase inhibition was investigated using 4-nitrophenyl butyrate (p-NPB) as a substrate. To uncover further therapeutic potentials of these medicinal plants, antimicrobial activity and minimum inhibitory concentration (MIC) of the extracts were also determined. The ethyl acetate plant extracts showed higher antimicrobial activity against Staphylococcus aureus, Escherichia coli, Salmonella typhi, and Shigella sonnei. The MIC of ethyl acetate extracts of medicinal plants considered in this study ranges from 1.56 to 6.25 mg/mL. The hexane fraction of Mimosa pudica and Phyllanthus emblica showed a higher lipase inhibitory activity as compared to others, with IC50 values of 0.49 ± 0.02 and 2.45 ± 0.003 mg/mL, respectively. In the case of Bergenia ciliata, the methanolic extract inhibited lipase more effectively than others, with an IC50 value of 1.55 ± 0.02 mg/mL (IC50 value of orlistat was 179.70 ± 3.60 µg/mL). A mass spectrometry analysis of various solvent/solvent partition fractions (extracts) revealed 29 major secondary metabolites. The research offers a multitude of evidence for using medicinal plants as antiobesity and antimicrobial agents.

Effects of Maturity and Thermal Treatment on Phenolic Profiles and In Vitro Health-Related Properties of Sacha Inchi Leaves

Sacha inchi (Plukenetia volubilis L.) has been adopted as a novel economic crop with well-studied nutritional and bioactive benefits for human health. Sacha inchi seeds and oil have high commercial value but scant research has focused on its leaves. This study investigated and compared phenolic compositions, antioxidant potentials and in vitro health-related properties of both young and mature sacha inchi leaves after freeze-drying and oven-drying processes. Results showed that p-coumaric acid, 4-hydroxybenzoic acid, ferulic acid and gallic acid were predominantly detected in both young and mature leaves that also exhibited similar total phenolic contents (TPCs), while higher TPCs were detected in freeze-dried than in oven-dried leaves. Mature leaves exhibited higher antioxidant potential than young leaves after freeze-drying, while the opposite results were observed for oven-drying. Overall in vitro health-related activities were higher in mature leaves compared to young leaves regardless of the drying process. Knowledge gained from this study can be used to encourage prospective utilization of sacha inchi leaves as a source of health-promoting compounds. This, in turn, will increase the commercial value of the leaves and provide a wider market variety of sacha inchi products.

Binding mechanism of lipase with Lentinus edodes mycelia polysaccharide by multi-spectroscopic methods

It is an effective strategy to avoid obesity by inhibiting the activity of lipase. In this study, the binding mechanism of lipase and Lentinus edodes mycelia polysaccharide (LMP) were explored with multi-spectral methods, for example, three-dimensional (3D) fluorescence, Fourier-transformed infrared (FT-IR), and Raman spectra. At 290 K, the binding constant was 2.44 × 10⁵  L/mol, there was only one binding site between LMP and lipase. Static quenching was the quenching mechanism. The major forces were hydrogen bonding and van der Waals force. The binding of LMP to lipase impacted the microenvironment around tyrosine and tryptophan residues. The polarity around these residues was decreased and hydrophobicity was enhanced. This study not only revealed the binding mechanism of LMP on lipase but also provided scientific evidence for expanding the application of LMP in functional food industries.

The mechanism of delaying starch digestion by luteolin

In this study, the mechanisms of the delay of starch digestion by luteolin were revealed by studying the luteolin-PPA (porcine pancreatic α-amylase) interaction and luteolin-starch interaction. The luteolin-PPA interaction was investigated by inhibitory kinetics analysis, fluorescence quenching, circular dichroism (CD), Fourier transform infrared (FT-IR) spectroscopy and molecular docking. The results of the inhibitory kinetics revealed that luteolin was a mixed-type inhibitor of PPA and that the inhibitory action was reversible. Fluorescence spectroscopy (including fluorescence quenching and thermodynamics) and molecular docking analyses indicated that hydrogen bonds and hydrophobic forces were the main forces between PPA and luteolin. CD and FT-IR spectroscopy analyses showed that the interaction between luteolin and PPA changed the secondary structure of PPA and induced a decline in its activity. In addition, the luteolin-starch interaction was also studied using UV-visible absorption and X-ray diffraction analyses. These indicated that luteolin could bind with PPA, and that hydrogen bonds and van der Waals forces may be present. Overall, luteolin delayed starch digestion not only by binding with PPA but also by binding with starch. Thus, luteolin has the potential to prevent and control diabetes by being added into starch-based food to delay starch digestion.

Inhibitory Effects of Myricetrin and Dihydromyricetin toward α-Glucosidase and Pancreatic Lipase with Molecular Docking Analyses and Their Interaction

The aim of the current study was to evaluate the interaction effects of myricetrin and dihydromyricetin in inhibiting α-glucosidase and pancreatic lipase at different combination ratios and concentrations and to illuminate the underlying mechanisms of their inhibitions by molecular docking analyses. Results showed that both phenolic compounds possessed good inhibitory effects toward two enzymes in a dose-dependent manner. Myricetrin demonstrated a stronger inhibition against α-glucosidase (IC50, 41.14 ± 2.52 and more than 200 μg/mL, respectively), while dihydromyricetin had a better pancreatic lipase inhibition (IC50, 244.96 ± 4.24 and 373.26 ± 21.36 μg/mL, respectively). Different interaction types were observed when myricetrin and dihydromyricetin inhibited α-glucosidase and pancreatic lipase in combination, which were closely related to the combination ratio and concentration. For α-glucosidase inhibition, synergistic effects were observed at relative low concentrations when the combination ratio of myricetrin to dihydromyricetin was set as 1 : 2, while strong synergistic effects existed at relative high concentrations for pancreatic lipase inhibition. In other combination ratios (1 : 1 or 2 : 1), additive and/or antagonistic effects occurred. Molecular docking analyses showed that myricetrin formed nine hydrogen bonds with α-glucosidase, while only three hydrogen bonds were formed between dihydromyricetin and α-glucosidase. However, these two phenolic compounds had similar hydrogen bonds and hydrophobic interactions with pancreatic lipase. The present study suggested that myricetrin and dihydromyricetin or food materials rich in these two phenolic compounds could be exploited as α-glucosidase and/or pancreatic lipase inhibitors to deal with health problems caused by excessive energy intake, and the combination ratio and concentration of these two phenolic compounds should be considered when producing new functional foods.

Inhibitory kinetics and mechanism of pentacyclic triterpenoid from endophytic Colletotrichum gigasporum against pancreatic lipase

The burden of obesity is increasing all over the world. Except for Orlistat, no effective anti-obesity drug is currently available. Therefore, a search for the new anti-obesity compound is need of time. This study demonstrates macromolecular interaction and inhibitory effect of pentacyclic triterpenoids (PTT) on pancreatic lipase (PL). In the present study PTTs from endophytic Colletotrichum gigasporum were found to show significant inhibitory activity against PL with IC₅₀ of 16.62 ± 1.43 μg/mL. The PTT isolated through bioassay-guided isolation showed a dose-dependent (R² = 0.915) inhibition against porcine PL and the results were comparable with the standard (Orlistat). Based on inhibition kinetic data, the gradual increase in K_{m (app)} with increasing PTT concentration indicated that the mode of interaction of PTT with PL was a competitive type, and it directly competed with the substrate (pNPB) for the active site of PL. In vivo studies in Wistar rats at the oral dose (100 mg/kg body weight) of PTT significantly decreased (p < 0.05) incremental plasma triglyceride levels as compared to group B and TG absorption was down-regulated up to 49.18% vis a vis group D animals. The isolated PTT was identified as lupeol based on chromatographic and spectral data. The endophytic isolate was identified as Colletotrichum gigasporum based on morphology and ITS gene sequencing. The present study indicated that PTT had the potential to be used as a natural PL inhibitor in the treatment of obesity and the isolated endophyte can be a valuable bioresource for it.

Design, synthesis, in silico molecular modelling studies and biological evaluation of novel indole-thiazolidinedione hybrid analogues as potential pancreatic lipase inhibitors

A series of thiazolidinedione-indole hybrids are designed and synthesized as a potential inhibitor for pancreatic lipase (PL).