Inhibition Of Pancreatic Lipase Research Articles

Investigation of the Therapeutic Value of Verbascum pyramidatum Bieb. for Obesity

Nowadays, one of the therapeutic approaches for obesity is the use pancreatic lipase inhibitors which reduce the digestion and absorption of fats. Most research indicates that natural sources which have a lipase inhibitory effect, may be utilized to treat obesity. Verbascum pyramidatum is one of the potential natural sources for obesity, and it has been demonstrated to have anti-inflammatory, antidiabetic, and regulatory effects on lipid metabolism. With this study, V. pyramidatum's potential lipase inhibitor effect, it is aimed to reveal its value in the treatment of obesity.
 In vitro spectroscopic method was used to determine the lipase inhibitory effect of V. pyramidatum. The quantitative investigation of V. pyramidatum's phenolic metabolites with antiobesity activity was carried out utilizing the Reverse Phase-High Performance Liquid Chromatography method.
 In this reported study, it was proven that extract and all fractions had an impact that inhibited lipase, with the ethyl acetate extract showing the highest inhibitory effect. Additionally, it was revealed through HPLC analysis that the species included p-OH benzoic acid, coumaric acid, quercetin, sinapic acid, and syringaldehyde. It has been demonstrated that V. pyramidatum may be a promising candidate for obesity treatment, but further investigations are required to use it as a therapeutic agent.

In Vitro Pancreatic Lipase, Alpha-Amylase and Αlpha-Glucosidase Inhibitory Activities of the Phytochemical Barbaloin

In the present study the phytochemical, barbaloin was studied for in-vitro pancreatic lipase, alpha (α)-amylase and alpha (α)-glucosidase inhibitory activities. The aim of this work is to evaluate the inhibitory activities of the phytochemical, barbaloin at different concentrations. Pancreatic lipase is an enzyme that hydrolyzes the lipids obtained from the diet which acts as an important target to treat obesity. The natural medicines that can inhibit pancreatic lipase enzyme and thus decrease absorption of dietary fat in the body gained much attention for the treatment and prevention of obesity. Diabetes mellitus is a metabolic disorder marked by an elevated level of glucose that circulates in the blood plasma. Alpha amylase and alpha glucosidase inhibitors are used to attain control over hyperglycemia in type 2 diabetes mellitus. The present study was designed to screen the novel pancreatic lipase, alpha amylase and alpha glucosidase inhibitors using a phytochemical, barbaloin in order to minimize the toxicity and side effects of the inhibitors which are used at present to treat the disorders like obesity and hyperglycemia. The phytochemical, barbaloin exhibited significant pancreatic lipase, α-amylase and α-glucosidase inhibitory activities with an IC50 value 5.52µg/ml, 8.22µg/ml and 5.81µg/ml respectively and well compared with standard orlistat for pancreatic lipase and acarbose for alpha (α)-amylase and alpha (α)-glucosidase inhibitory activities respectively.

Effect of ultra-high pressure treatment on structural and functional properties of dietary fiber from pomelo fruitlets

The effects of ultra-high pressure treatment on structural and functional properties of dietary fiber from pomelo fruitlets were analyzed. The results showed that ultra-high treatment changed monosaccharide composition, increased total dietary fiber and soluble dietary fiber from pomelo fruitlets, especially at 400 MPa where soluble dietary fiber was greatly increased from 32.49% ± 0.23% to 41.92% ± 0.32% as compared to native one (p < 0.05). Besides, ultra-high pressure treatment enhanced water- and oil-holding capacity, as well as swelling capacity of dietary fiber, which were related to its more porous structure and hydrophobic groups. Crystallinity and thermal stability of ultra-high pressure modified dietary fibers increased. Moreover, ultra-high pressure modified dietary fibers possessed stronger bile acid binding and pancreatic lipase inhibition capacities, suggesting its better potential in vitro hypolipidemic activity. Our findings suggested that ultra-high pressure treatment is a promising method to obtain dietary fiber with excellent functional properties, and can provide a basis for the high-value utilization of pomelo fruitlets as functional food with blood-lipid regulation.

In vitro anti-obesity activity by pancreatic lipase inhibition - Simple HPLC approach using EVOO as natural substrate.

Pancreatic lipase (PL) is a key lipolytic enzyme in humans for the digestion and absorption of dietary fats. Thereby, PL is a well-recognized target in the management of obesity and its inhibition attracts the interest of researchers globally. The screening of new natural PL inhibitors as alternative strategy to the synthesis of chemical ones represents nowadays a hot topic in research. The main challenge in this matter is the lack of a universal analytical method allowing the monitoring of PL activity and the reliable quantification of lipid digestion products. The (normal phase)-high-performance liquid chromatography-evaporative light scattering detector [(NP)-HPLC-ELSD] method proposed in this work represents a direct and rapid strategy to simultaneously quantify the products obtained from in vitro PL digestion. As one of the main novelties, the triacylglycerol (TAG) fraction from extra-virgin olive oil was selected as natural substrate. The PL activity was measured by monitoring the levels of remaining TAGs and formed free fatty acids (FFAs), using Orlistat as known inhibitor. The method validation confirmed the adequacy of the analytical method for quantitative purposes, showing high recovery percentage values (between 99% and 103%) and low relative standard deviation (RSD%) values (between 2% and 7%) for triolein and oleic acid standard solutions, as well as appreciably low limit of detection (LOD) and limit of quantification (LOQ) values (respectively 58 and 177 ng mL-1 for triolein; 198 and 602 ng mL-1 for oleic acid). Finally, the developed HPLC-ELSD method was successfully applied to evaluate the inhibitory effect of a polyphenolic extract obtained from apple pomace. The results showed a comparable inhibition degree between a 4.0mg mL-1 apple pomace solution and a 1.0μg mL-1 Orlistat solution. The proposed innovative method reveals highly sensitive and simple to follow the fate of PL digestion, thus opening the way to further investigations in the research of new potentially anti-obesity compounds. © 2022 Society of Chemical Industry.

Isolation and Identification of Lipid-Lowering Peptides from Sacha Inchi Meal.

Sacha inchi meal (SIM) is a by-product of sacha inchi (considered as a "super-food") processing. In previous studies, we found that SIM protein hydrolysates exhibited pancreatic lipase inhibition activity. In this study, 10 bioactive peptides from those hydrolysates were identified. The top five peptides (NLYYKVV (NV-7), WWYVK (WK-5), WLLMWPYK (WK-8), EGLLMWPY (EY-8), and FPFFGYVWK (FK-9)) with strong pancreatic lipase inhibition activity had IC50 values of 34.01-246.50 µM, and displayed various inhibition types (mixed, non-competitive, and competitive type) by enzyme inhibition kinetics analysis. Fluorescence quenching analysis demonstrated that the interaction between the peptides and pancreatic lipase was mainly hydrogen bond and van der Waals force. The key residues involved in the peptide-enzyme interaction were determined by molecular docking. Moreover, the top two peptides were found to significantly inhibit fat accumulation and regulate lipid metabolism by alleviating the level of reactive oxygen species in HepG2 cells. Collectively, sacha inchi meal-derived peptides displayed potent lipid-lowering activity and could be used as materials of functional food.

Discovery of A Novel Synthetic Thiazole-benzimidazole Conjugate that Acts as a Potent Pancreatic Lipase Inhibitor using in silico and in vitro Approaches

Abstract: Aim/ Background: Pancreatic lipase (PL) inhibition has been suggested to be an effective method for obesity management. In this study, 10 novel thiazole-benzimidazole conjugates were designed. Materials and Methods: Conjugates were initially screened via in silico experiments, such as ADMET analysis and molecular docking, to identify the most promising PL inhibitors. Results: Results revealed that compounds 3, 6 and 8 had the most optimum druglikeness properties, and the highest binding affinity to PL, with binding energies of -7.7, -7.5 and -8.1 kcal/mol, respectively. Therefore, these promising derivatives were then synthesized and subjected to an in PL inhibition assay to validate the results of the in silico experiments. The synthetic compounds were fully characterized via FTIR, 1H-NMR, 13C-NMR and LCMS. Results of the enzymatic assay revealed that 3, 6 and 8 inhibited PL potently with high inhibition rates of greater than 80% at the highest tested dose, and demonstrated IC50 values of 68.53, 54.97 and 50.09 μM, respectively. Compound 8 was the most active derivative and displayed comparable activity to orlistat which possessed an IC50 value of 39.18μM. Conclusion: Therefore, we report the discovery of compound 8 as a highly potent PL inhibitor that could act as a lead compound to develop novel anti-obesity agents. Keywords: Pancreatic lipase, Inhibition, Thiazole-benzimidazole, in silico, in vitro, Enzyme assay.

Co-extraction of soy protein and polysaccharide with lipid-lowering activity: Characterization of functional property, nutritional property and colonic fermentation property through a metabolomics approach

Defatted soy meal is a candidate for preparing lipid-lowering active ingredient. The study aimed to optimally co-extract soy protein and polysaccharide with lipid-lowering activity and improved functional and nutritional properties using non-conventional extraction techniques, i.e. thermal-, high pressure homogenization- and enzyme-assisted extraction. Non-conventional extraction enhanced the yields of soy protein and soluble saccharides and inactivated anti-nutrients. Soy extract (SE) prepared by pectinase-assisted extraction possessed not only strong in vitro lipid-lowering activity (i.e. cholesterol micellar inhibition activity, bile salts binding capacity, pancreatic lipase inhibition activity and cholesterol esterase inhibition activity), but also excellent functional (i.e. instant solubility of protein, low turbidity and acceptable color) and nutritional properties (i.e. none agglutinin activity). Resistant-digested fragment of 7S/11S played key role in lipid-lowering activity of SE. Moreover, SE beneficially altered colonic fermentation property of soy protein through promoting the release of bioactive peptides and organic acids, accelerating tryptophan and linoleic acid metabolism to produce indole acrylic acid, indole lactic acid and linoleic acid, and inhibiting putrefactive compounds (i.e. piperidine and tyramine). Oligosaccharide and polysaccharide in SE improved functional and nutritional properties of soy protein without compromising its lipid-lowering activity.

Purple tea: chemical characterization and evaluation as inhibitor of pancreatic lipase and fat digestion in mice.

A variety of the classic green tea plant, Camellia sinensis, was developed and is exclusive to Kenya. Due to high content of anthocyanin polyphenols in its leaves, the beverage obtained from this variety is purple in color and is the origin of the name purple tea. This work had two main purposes. The first one was to identify and quantify the major anthocyanin polyphenols in a hot water aqueous extract of the purple tea leaves. The second one was to test the hypothesis if this extract is capable of inhibiting triglyceride absorption considering that anthocyanin polyphenolics have been frequently associated to antilipidemic effects. Parallel experiments were always done with a similar green tea extract for comparison purposes. The antioxidant, anti-inflammatory, and cytotoxic activities of both tea varieties are similar. The purple tea extract, however, was strongly inhibitory toward the pancreatic lipase (minimal IC50 = 67.4 μg mL-1), whereas the green tea preparation was a weak inhibitor. Triglyceride digestion in mice was inhibited by the purple tea extract starting at 100 mg kg-1 dose and with a well-defined dose dependence. Green tea had no effect on triglyceride digestion at doses up to 500 mg kg-1. The latter effect is probably caused by several components in the purple tea extract including non-anthocyanin and anthocyanin polyphenols, the first ones acting solely via the inhibition of the pancreatic lipase and the latter by inhibiting both the lipase and the transport of free fatty acids from the intestinal lumen into the circulating blood. The results suggest that the regular consumption of Kenyan purple tea can be useful in the control of obesity.

Anti-obesity and anticancer activity of Solanum xanthocarpum leaf extract: An in vitro study

Background: Solanum xanthocarpum grows in parts of India as a wild herb. The active principles of this plant are Solasodine, Carpesterol, β-Sitosterol, and Diosgenin. Pharmacological effects such as hypoglycemic, hepatoprotective and hypotensive activity of S. xanthocarpum have been reported. Solasodine, an active component of this plant is reported to have antioxidant activity. Aims and Objectives: The objective of this study is to evaluate the anticancer and anti-obesity property of S. xanthocarpum. Materials and Methods: This study was carried out in Department of Pharmacology, Government Kilpauk Medical College, with laboratory support from Life Teck Research Center, Chennai. Both dry and fresh leaves of S. xanthocarpum were taken and evaluated for anticancer property using MCF cell line and anti-obesity activity using Pancreatic Lipase inhibition activity. Results: There was significant decrease in cell viability with increase in concentration of both dry and fresh leaves which shows anticancer activity. With increase in concentrations of leaf extracts, the inhibition of pancreatic lipase was found but in comparison to Orlistat the standard treatment, the effect was very less. Conclusion: Based on above results, it is concluded that S. xanthocarpum has good anticancer and minimal anti-obesity activity. Further investigations are required to identify the actual phytoactive component.

Comparative evaluation of anti-obesity effect through pancreatic lipase inhibition of methanolic extract of the bark of Saraca asoca and Cynometra travancorica

Comparative evaluation of anti-obesity effect through pancreatic lipase inhibition of methanolic extract of the bark of Saraca asoca and Cynometra travancorica

Protective Effect of Dolichos biflorus Seed Extract on 3T3‐L1 Preadipocyte Differentiation and High‐Fat Diet‐Induced Obesity in Rats

Obesity is known to be one of the severe health issues worldwide, as its prevalence continues to rise as well as its association with other chronic diseases worsens. Even though various approaches have been underway to prevent or treat obesity, alternative approaches are in need to combat this chronic condition because of the unsatisfactory effectiveness and adverse side effects of the existing approaches. Dolichos biflorus L. seeds have been employed as a weight‐loss treatment in folk medicine. Considering the necessity to develop a safe alternative remedy to rising obesity, the current investigation has been set up to assess the antiobesity potential and the mode of action of the aqueous seed extract of D. biflorus (ASEDB) in a cell line (3T3‐L1) and high‐fat diet (HFD)‐induced rats. For in-vitro studies, 3T3‐L1 cell lines were cultured in Dulbecco’s modified Eagle medium (DMEM) augmented with adipogenic‐inducing medium and the influence of the extract (10 µg/mL–500 µg/mL) on 3T3‐L1 adipocyte viability, adipogenesis, and lipolysis was assessed. An in-vitro study revealed maintenance of cell viability, reduced triglycerides (TG) accumulation, and promoted lipolysis in 3T3‐L1 cells by ASEDB. Following in-vitro analysis, the HFD‐induced obese rats were treated with ASEDB at different concentrations (100 mg/kg, 200 mg/kg, and 300 mg/kg) for 60 days and the effect was evaluated through various anthropometric and biochemical parameters. The findings revealed a significant decrement in total body weight, organ weights, fat pad weights, and restoration of abnormal levels of glucose, leptin, insulin, lipid markers, and antioxidant system to normal by ASEDB treatment. Also, pancreatic lipase inhibition analysis of ASEDB revealed a modest level of inhibition with an IC50 value of 213.3 µg/mL. All these findings exposed that ASEDB possesses pronounced antiobesity potential and exhibits its protective effect by suppressing food intake, reducing fat digestion and absorption, limiting adipogenesis, enhancing lipolysis, and alleviating oxidative stress.

Pancreatic lipase related protein 1 as a potential target in triglyceride breakdown: A molecular docking studies with in vitro appraisal

Targeting obesity by altering the absorption of dietary triglycerides by inhibiting the pancreatic lipase is an interesting exploration. We aimed to understand the role of pancreatic lipase related protein 1 (PLRP1) and to explore whether flavonoids could bind to the protein and provide a treatment option for obesity. The selected 50 known plant-derived flavonoids have been tested for pancreatic lipase inhibition activity. The molecular docking analysis were performed to understand the binding interactions of the protein and molecules that have not been previously reported, along with in vitro pancreatic lipase enzyme activity of four flavonoid molecules to support the docking studies. The reported flavonoid molecules were also screened for parameters such as drug-likeness and oral bioavailability. Amongst the 50 tested flavonoid molecules, 13 molecules showing poor GI-absorption in the study. Of note, from the 13 molecules, (−)-epicatechin, cyanidin, petunidin and peonidin were predicted to exhibit the most potent binding with the protein target involving the Glu102, Ser129, ILE 97 and TRP270 residues to be the hotspots towards protein binding. The in vitro results demonstrated that the compound petunidin was potent inhibitor when compared to the control. Also, the kinetics data for all the compounds showed to possess an uncompetitive type of inhibition. Therefore, the findings of this study will be able to deliver useful insights to researchers in designing interesting weight-control drugs. Also, PLRP1 protein could open us a new insight and as an interesting target approach in the triglyceride breakdown for the management of obesity.

Antioxidant, Anti-Diabetic, Anti-Obesity, and Antihypertensive Properties of Protein Hydrolysate and Peptide Fractions from Black Sesame Cake.

A low-value by-product of cold-pressed sesame oil is defatted black sesame cake (DBSC). The remaining protein and essential amino acids may be utilized as a renewable biological source to produce bioactive products. The bioactivities of the protein hydrolysate from black sesame cake and its peptide fractions were examined in this study for in vitro antioxidant activity and inhibition of DPP-IV, ACE, α-amylase, α-glucosidase, and pancreatic lipase. By using Flavourzyme to hydrolyze DBSC, followed by ultrafiltration, fractions with peptide sizes of <3, 3−10, and >10 kDa were obtained. According to the findings, the products of DBSC could neutralize free radicals and prevent ferric ion redox reactions. The highest inhibitory effects were shown with low Mw peptides (<3 kDa) against ACE, DPP-IV, α-amylase, and α-glucosidase. DBSC has demonstrated potential as a nutraceutical or functional ingredient for preventing and treating disorders associated with free radicals, such as diabetes, hypertension, and hyperglycemia.

Screening of Pancreatic Lipase Inhibitors of Endophytic Fungi of Medicinal Plants in Uzbekistan

Search for pancreatic lipase (PL) inhibitors is essential for obesity and associated chronic disease therapy. PL inhibitors significantly reduce enzyme activity and prevent the absorption and hydrolysis of triglycerides into free fatty acids. This study provides new evidence of screening PL inhibitory activity of 15 endophytic fungi from 6 medicinal plants in Uzbekistan. In general, the extracts of almost all twelve endophytes exposed the inhibitory potential, but only five of them had inhibition levels above 50%. The highest inhibitory activity, amounting to 73.7% and 65.2%, and comparable to the activity of Xenical as a standard, was established for Fusarium sp.-AL142R and F.sambucinum - AL135L, respectively, isolated from the endemic plant Allium longicuspis. The values of IC50 inhibitory activity are 20.7 and 8.01, respectively, compared with Xenical as a standard with IC50 20.6 μg/ml. The inhibitory extracts of both endophytes contain alkaloids, terpenoids, flavonoids, and tannins. The data obtained for the first time indicate the potential of Uzbekistan plant endophytes as possible sources of PL inhibitors

Molecular docking and in silico drug-likeness studies of Garcinia prainiana King bioactive compounds as pancreatic lipase inhibitors

Garcinia prainiana King is an underutilized local fruit possessing high value in numerous therapeutic uses. Unlike other Garcinia species such as G. cambogia and G. atroviridis, the anti-obesity effect of G. prainiana has never been evaluated. Thus, in the present study, the inhibitory potential of bioactive compounds from G. prainiana towards pancreatic lipase, an enzyme involved in fat digestion that caused obesity was evaluated. A molecular docking study of eleven G. prainiana bioactive compounds against pancreatic lipase was performed followed by in silico drug-likeness prediction using the SwissADME tool. The docking study demonstrated that amentoflavone is the top compound showing the highest inhibition activity towards pancreatic lipase compared to other compounds. Two hydrogen bonds were formed between amentoflavone and two catalytic residues, Ser152 and His263 of pancreatic lipase. The formation of hydrophobic interactions with the lid residues, Ala260 and Ala259, may also contribute to the inhibitory effect of this compound. Other than amentoflavone, 4‴-methylamentoflavone and naringenin 7-o-β-D-glucuronide also exhibited high inhibition activities against pancreatic lipase by interacting with the catalytic and lid residues through hydrogen bonds. However, in the context of drug developability, naringenin 7-o-β-D-glucuronide was predicted to have a higher potential to be an oral drug candidate compared to amentoflavone and 4‴-methylamentoflavone. In conclusion, this study indicated the potential of G. prainiana compounds, particularly amentoflavone, 4‴- methylamentoflavone and naringenin 7-o-β-D-glucuronide as new pancreatic lipase inhibitors. However, naringenin 7-o-β-D-glucuronide has a higher drug-likeness potential that could serve as a drug candidate for the development of an anti-obesity agent.

Lipase activity inhibited by aloenin A: Glycoside from Aloe vera (L.) Burm. f.-In vitro and molecular docking studies.

Obesity is taking over many parts of the world and has been identified as the second leading cause of preventable death, with a dramatic increase in prevalence over the last two decades. Pancreatic lipase is a lipid-digesting enzyme that plays an important role in fat metabolism. Inhibiting pancreatic lipase is an attractive target for obesity treatment. Phytochemicals or bioactive compounds/extracts isolated from medicinal plants offer a promising platform for the development of pancreatic lipase inhibitors. This study aims to characterize and investigate the effect of aloenin A, glycoside found in Aloe vera, as a possible inhibitor of pancreatic lipase in vitro and in silico. A. vera extract had an IC50 value of 0.5472 μg/ml, whereas aloenin A had an IC50 value of 14.95 μg/mL and was found to inhibit in a competitive manner. These findings were supported by molecular docking studies, which revealed that aloenin A binds to the substrate binding site with a binding energy of - 7.16 kcal/mol, and this binding site is stabilized by three hydrogen bonds contributed by Phe77 and Asp79 . Our findings suggest that the anti-hyperlipidemic effects of A. vera on pancreatic lipase can be attributed in part to the presence of aloenin A.

Fungal Bergamotane Sesquiterpenoids-Potential Metabolites: Sources, Bioactivities, and Biosynthesis.

The marine environment represents the largest ecosystem on the Earth's surface. Marine-derived fungi are of remarkable importance as they are a promising pool of diverse classes of bioactive metabolites. Bergamotane sesquiterpenoids are an uncommon class of terpenoids. They possess diverse biological properties, such as plant growth regulation, phototoxic, antimicrobial, anti-HIV, cytotoxic, pancreatic lipase inhibition, antidiabetic, anti-inflammatory, and immunosuppressive traits. The current work compiles the reported bergamotane sesquiterpenoids from fungal sources in the period ranging from 1958 to June 2022. A total of 97 compounds from various fungal species were included. Among these metabolites, 38 compounds were derived from fungi isolated from different marine sources. Furthermore, the biological activities, structural characterization, and biosynthesis of the compounds are also discussed. The summary in this work provides a detailed overview of the reported knowledge of fungal bergamotane sesquiterpenoids. Moreover, this in-depth and complete review could provide new insights for developing and discovering new valuable pharmaceutical agents from these natural metabolites.

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.

Canary Seed (Phalaris canariensis L.) Peptides Prevent Obesity and Glucose Intolerance in Mice Fed a Western Diet

Previous research showed that canary seed (Phalaris canariensis L.) peptides (CSP) possess robust in vitro antiobesity properties via inhibition of pancreatic lipase (PL). Nevertheless, no studies have yet explored their antiobesity properties in vivo. Consequently, we investigated the effects of CSP in C57BL/6J mice under a Western diet (WD). Mice were assigned into groups and fed a normal diet (ND) or a WD accompanied by an oral dose of CSP (250 or 500 mg/kg/day), orlistat (40 mg/kg/day), or distilled water. The results showed that consuming CSP can provide metabolic benefits, including preventing weight gain by up to 20%, increasing glucose tolerance, and reducing insulin, leptin, and LDL/VLDL levels in plasma. Conversely, total ghrelin was unaffected by CSP-500, but decreased by CSP-250, and amplified by orlistat. Surprisingly, CSP-250 was more effective in preventing weight gain and promoting satiety than CSP-500. Parallel to this, protein absorption in CSP-500 was decreased, supported by a rise in fecal crude protein (+3.5%). Similarly, fecal fat was increased by orlistat (38%) and was unaffected by CSP-250 (3.0%) and CSP (3.0%), comparatively to WD (2.5%). Despite this, both CSP treatments were equally effective in decreasing hepatic steatosis and avoiding hyperlipidemia. Furthermore, the enzymatic analysis showed that CSP-PL complexes dissociated faster (15 min) than orlistat-PL complexes (41 min). Lastly, CSP did not affect expression of hepatic lipid oxidation genes ACO and PPAR-α, but reduced the expression of the hydrolase gene LPL, and lipogenesis related genes FAS and ACC. Taken together, these results suggest that CSP antiobesity mechanism relies on lipid metabolism retardation to increase fat transit time and subsequently suppress hunger.

Sweet potato extract alleviates high-fat-diet-induced obesity in C57BL/6J mice, but not by inhibiting pancreatic lipases.

Sweet potato is widely consumed as a healthy and nutritive vegetable containing bioactive constituents for health promotion. This study investigated the beneficial impact of white-fleshed sweet potato extract (SPE) on high fat diet (HFD)-induced obese mice. First, SPE, in which resin glycoside was found as the dominant constituent, was suggested as a potential anti-obesity agent, because 20-70% pancreatic lipase (PL) inhibition was measured with SPE by in vitro turbidity assay and pNPP assay. Hence, next, the effect of SPE on obese mice was detected by oral administration of HFD supplemented with 6% SPE on C57BL/6J mice for 9 weeks. Surprisingly, being the opposite of what was typically observed from a lipase inhibitor such as orlistat, the fecal fat content in SPE-fed obese mice was decreased (p < 0.01). Meanwhile, 6% SPE supplement indeed significantly ameliorated HFD-induced obesity in mice, including body weight gain, fat accumulation, adipocyte enlargement, insulin resistance, and hepatic steatosis (p < 0.05). The improved liver steatosis was found associated with a down-regulating action of SPE on nuclear factor kappa B activation in HFD-fed mice. The anti-obesity influence of SPE was also confirmed on the HepG2 cell model for non-alcoholic fatty liver disease (NAFLD). These results indicate that SPE, as a dietary supplement, has the great potential for weight control and treating hepatic steatosis, possibly through a different action mechanism from that of orlistat.