Determination of the kinetic properties of platycodin D for the inhibition of pancreatic lipase using a 1, 2-diglyceride-based colorimetric assay

A 1,2-diglyceride-based multi-step colorimetric assay to measure the pancreatic lipase activity was applied for the determination of the kinetic profiles of the lipase inhibition with a slight modification and the validity verification. With this assay method, our study revealed that platycodin D, one of major constituents of Platycodi Radix, inhibits the pancreatic lipase activity in a competitive type, with the value of KI being 0.18+/-0.02 mM. In addition, PD has affected the values of K(m,app) and Kcat/Km in a dose-dependent manner. The results shed a meaningful light on how PD mediates lipid metabolism in the intestinal tracts. On the other hand, since the revised assay is sensitive, rapid, and does not affect the accuracy to the kinetic properties, it is applicable not only to evaluation of the kinetic properties of the pancreatic lipase, but also to high-throughput screening of pancreatic lipase activity.     

桔梗的化学成分和抗肿瘤活性研究进展

桔梗作为一种药食两用的植物,具有显著的镇咳祛痰、抗肿瘤、抗氧化及降血糖等作用。迄今为止,从桔梗中共分离得到55种皂苷类化合物,三萜皂苷是其主要的活性成分。本文对近年来桔梗的化学成分研究进展进行了总结,并从诱导肿瘤细胞凋亡、增强机体免疫功能、抑制端粒酶活性、抑制肿瘤细胞浸润与转移以及阻滞细胞周期等方面,对国内外桔梗抗肿瘤活性的研究进展进行了阐述。     

Determination of the kinetic properties of platycodin D for the inhibition of pancreatic lipase using a 1,2-diglyceride-based colorimetric assay

A 1, 2-diglyceride-based multi-step colorimetric assay to measure the pancreatic lipase activity was applied for the determination of the kinetic profiles of the lipase inhibition with a slight modification and the validity verification. With this assay method, our study revealed that platycodin D, one of major constituents of Platycodi Radix, inhibits the pancreatic lipase activity in a competitive type, with the value ofK _l being 0.18±0.02 mM. In addition, PD has affected the values ofK _{m, app} andK _cat/K _m in a dose- dependent manner. The results shed a meaningful light on how PD mediates lipid metabolism in the intestinal tracts. On the other hand, since the revised assay is sensitive, rapid, and does not affect the accuracy to the kinetic properties, it is applicable not only to evaluation of the kinetic properties of the pancreatic lipase, but also to highthroughput screening of pancreatic lipase activity.     

Isolation of pancreatic lipase activity-inhibitory component of spirulina platensis and it reduce postprandial triacylglycerolemia

In the process of investigating the hypolipidemic effects of Spirulina platensis, we found that the aqueous extract of S. platensis may inhibit the intestinal absorption of dietary fat by inhibiting pancreatic lipase activity. The aqueous extract of S. platensis (500 m/kg) reduced the elevation of rat plasma triacylglycerol levels after oral administration of the lipid emulsion 2 h after administration. To clarify the hypolipidemic effects of S. platensis, the active component was isolated and designated 1'-O-(palmitonyl)-2'-O-(caprylonyl) glyceryl-beta-alpha-D-galactopyranoside (glycolipid H-b2). Glycolipid H-b2 was found to inhibit pancreatic lipase activity in a dose-dependent manner. The fractions containing glycolipid H-b2 (250 mg/kg) reduced the elevation of rat plasma triacylglycerol levels after oral administration of the lipid emulsion 2 h after administration. Furthermore, we examined the effects of phycocyanin isolated from S. platensis on pancreatic lipase activity. Phycocyanin inhibited the pancreatic lipase activity in a dose-dependent manner. These results suggest that the inhibitory effects of S. platensis on postprandial triacylglycerolemia may be due in part to the inhibition of pancreatic lipase activity by glycolipid H-b2 and phycocyanin.     

Medicinal plant and its related metabolic modulators]

We suggested a strategy for identifying anti-obesity drugs. The strategy aimed to prevent obesity through inhibiting intestinal absorption of dietary fat. Intestinal absorption of dietary fat was found to be reduced by tea saponin and chitosan through inhibiting pancreatic lipase activity, by chondroitin sulfate through inhibiting both pancreatic lipase activity and fatty acid absorption, and by lactosucrose through inhibiting beta-monoglyceride absorption. All these functional substances reduced plasma triglyceride levels previously elevated by oral administration of a lipid emulsion containing corn oil. Furthermore, these substances were found to cause reduction in perimetrial adipose tissue weight, which had been elevated by oral administration of a high fat diet (containing 40% of beef tallow) to female mice. Based on these results, a strategy for identifying anti-obesity drugs was discussed.     

甘草及其活性成分的表面活性比较研究

目的 研究甘草及其活性成分的表面活性,为更合理地研究甘草中成分的增溶能力提供参考.方法 在不同温度下,采用Wilhelmy吊片法测定溶液的表面张力和溶液的临界胶束浓度(CMC).结果 分析了溶液的表面活性效能、效率和表面过剩浓度,甘草水煎液表面活性较好.结论 甘草中除皂苷组分具有表面活性外,其他组分对表面活性有贡献.     

The anti-obesity potential of sigmoidin A

Context: During the last few decades, the prevalence of obesity in the western world has dramatically increased with epidemic proportions. Hand in hand with this statistic, the incidences of obesity-linked diseases such as diabetes are increasing with pandemic rate. The search for novel drugs and nutritional intervention approaches for obesity is now of significant importance.

Objective: The anti-obesity potential of eriodictyol (ERD) and its close structural analogue, sigmoidin A (SGN), were evaluated. SGN was isolated from Erythrina abyssinica Lam. ex DC. (Fabaceae).

Materials and methods: Concentrations between 300 and 0.1 µM of test samples and reference drugs made in three-fold dilutions were tested for enzyme inhibitory effects. The major obesity target, pancreatic lipase, was used to test the anti-obesity potential while the selective effects of the compounds were determined through assessments of effects on α-glucosidase.

Results: The inhibitory effect of SGN on pancreatic lipase (IC₅₀, 4.5 ± 0.87 µM) was 30-times greater than that of ERD (IC₅₀, 134 ± 19.39 µM) while their effect on α-glucosidase enzyme was comparable (IC₅₀ value of 62.5 ± 9.47 and 57.5 ± 13.15 µM). The anti-obesity drug, orlistat, inhibited pancreatic lipase with an IC₅₀ value of 0.3 ± 0.04 µM, while the anti-diabetic drug, acarbose, inhibited α-glucosidase with an IC₅₀ value of 190.6 ± 16.05 µM.

Discussion: Although less active than the standard anti-obesity drug, orlistat, the observed activity indicated that prenylation of the flavonoid skeleton potently enhances anti-lipase activity.

Conclusion: Such groups of flavonoids need to be further investigated for their therapeutic and nutritional benefit in combating obesity problems.     

新疆两色金鸡菊模拟茶饮自由基清除、胰脂肪酶活性抑制及成分分析

目的：考察新疆两色金鸡菊模拟茶饮水提取物清除自由基、胰脂肪酶活性抑制能力,并对其成分进行HPLC分析。方法：采用去离子纯净水煎煮两色金鸡菊获得模拟茶饮水提取物。对模拟茶饮水提取物进行DPPH、ABTS⁺·、·OH和NO·自由基的清除能力考察;同时考察模拟茶饮水提取物对胰脂肪酶活性抑制能力;使用HPLC法分析模拟茶饮水提取物中的主要物质成分。结果：模拟茶饮水提取物对DPPH自由基的清除能力（SC₅₀）为（228.6±4.61）μg·mL^-1;对ABTS^+·自由基的清除能力（SC₅₀）为（128.4±5.83）μg·mL^-1;对·OH自由基的清除能力（SC₅₀）为（22.41±1.13）μg·mL^-1;对NO·自由基的清除能力（SC₅₀）为（149.8±11.6）μg·mL^-1;对胰脂肪酶活性抑制能力（IC₅₀）为（366.4±8.12）μg·mL^-1。经HPLC成分分析,模拟茶饮水提取物主要含有绿原酸、黄诺马苷、栎草亭-7-O-β-D-吡喃葡萄糖苷、马里苷、异奥卡宁和奥卡宁等成分。结论：新疆两色金鸡菊模拟茶饮水提取物具有一定的自由基清除能力,同时具有一定的抑制胰脂肪酶活性的能力。     

桔梗生长年限和采收期与质量的相关性研究

目的确定桔梗最佳生长年限与最佳采收期。方法蒽酮比色法测定多糖含量;HPLC测定桔梗皂苷D含量;改进的总苷称重法测定总皂苷含量。结果以两年生,9月下旬至11月上旬采收的桔梗质量最佳。结论三种指标具有代表性,能够较全面反映药材质量。     

Pancreatic lipase activation,inhibition, and relationship to peroxide oxidation of lipids

The influence of biologically active indolalkylamines (serotonin and tryptamine), amino acids (tryptophan), and catecholamines (epinephrine and norepinephrine) on the activity of pancreatic lipase has been studied. It is established that the biologically active monoamines inhibit lipid peroxidation and potentiate the lipase activity. Ascheme of relationships between the enzymatic and chemical conversion pathways of natural lipids is presented. The influence of biologically active monoamines on these processes is considered. It is shown that heavy-metal ions contaminating water produce a significant effect on the lipase activity. The proposed method of determination of the lipase activity can be considered as a promising biotest in ecological investigations.     

醋柴胡不同极性洗脱部位对黄芩苷在小鼠体内分布的影响以及成分分析

目的 考察醋柴胡不同极性洗脱部位对黄芩苷在小鼠体内分布的影响，并运用相关性分析初步探讨醋柴胡配伍黄芩苷在不同脏器中的增效活性成分。方法 通过多次给药，LC-MS/MS测定小鼠各组织中黄芩苷的含量，考察醋柴胡不同极性洗脱部位对黄芩苷在小鼠体内分布的影响；Q-Exactive Plus对醋柴胡不同极性部位的成分进行分析，SPSS 21.0软件进行相关性分析并探讨可能活性成分。结果 与黄芩苷单用组相比，联用组（95%乙醇洗脱部位）肝脏、肺脏、脾脏中黄芩苷浓度升高，75%乙醇洗脱部位肺脏中药物浓度升高，50%乙醇洗脱部位脾脏中药物浓度升高；成分相关性分析结果表明醋柴胡中21个化合物与黄芩苷在小鼠肝脏中分布呈显著性正相关，主要为醋制后产生的乙酰化皂苷；另13个化合物与黄芩苷在小鼠肺脏分布呈显著性相关，主要为生柴胡皂苷。结论 乙酰化皂苷、生柴胡皂苷可能分别是醋柴胡治疗肝脏、肺脏疾病的活性成分，其结果有待进一步验证。     

Anti-obesity effects of galangin,a pancreatic lipase inhibitor in cafeteria diet fed female rats

Abstract

Context: Alpinia galanga Willd (Zingiberaceae) (AG) is a rhizomatous herb widely cultivated in shady regions of Malaysia, India, Indochina and Indonesia. It is used in southern India as a domestic remedy for the treatment of rheumatoid arthritis, cough, asthma, obesity, diabetes, etc. It was reported to have anti-obesity, hypoglycemic, hypolipidemic and antioxidant properties.

Objective: A flavonol glycoside, galangin, was isolated from AG rhizomes. Based on its in vitro pancreatic lipase inhibitory effect, the study was further aimed to clarify whether galangin prevented obesity induced in female rats by feeding cafeteria diet (CD) for 6 weeks.

Materials and methods: The in vitro pancreatic lipase inhibitory effect of galangin was determined by measuring the release of oleic acid from triolein. For in vivo experiments, female albino rats were fed CD with or without 50?mg/kg galangin for 6 weeks. Body weight and food intake was measured at weekly intervals. On day 42, serum lipids levels were estimated and then the weight of liver and parametrial adipose tissue (PAT) was determined. The liver lipid peroxidation and triglyceride (TG) content was also estimated.

Results: The IC₅₀ value of galangin for pancreatic lipase was 48.20?mg/mL. Galangin produced inhibition of increased body weight, energy intake and PAT weight induced by CD. In addition, galangin produced a significant decrease in serum lipids, liver weight, lipid peroxidation and accumulation of hepatic TGs.

Conclusion: Galangin present in AG rhizomes produces anti-obesity effects in CD-fed rats; this may be mediated through its pancreatic lipase inhibitory, hypolipidemic and antioxidant activities.     

Natural inhibitors of pancreatic lipase as new players in obesity treatment

Obesity is a multifactorial disease characterized by an excessive weight for height due to an enlarged fat deposition such as adipose tissue, which is attributed to a higher calorie intake than the energy expenditure. The key strategy to combat obesity is to prevent chronic positive impairments in the energy equation. However, it is often difficult to maintain energy balance, because many available foods are high-energy yielding, which is usually accompanied by low levels of physical activity. The pharmaceutical industry has invested many efforts in producing antiobesity drugs; but only a lipid digestion inhibitor obtained from an actinobacterium is currently approved and authorized in Europe for obesity treatment. This compound inhibits the activity of pancreatic lipase, which is one of the enzymes involved in fat digestion. In a similar way, hundreds of extracts are currently being isolated from plants, fungi, algae, or bacteria and screened for their potential inhibition of pancreatic lipase activity. Among them, extracts isolated from common foodstuffs such as tea, soybean, ginseng, yerba mate, peanut, apple, or grapevine have been reported. Some of them are polyphenols and saponins with an inhibitory effect on pancreatic lipase activity, which could be applied in the management of the obesity epidemic.     

Identification of novel saponins from edible seeds of Japanese horse chestnut (Aesculus turbinata Blume) after treatment with wooden ashes and their nutraceutical activity

Natural seeds of Japanese horse chestnut (Aesculus turbinata Blume) contain large amounts of mixed triterpenoidal saponins called escins. Recent studies have shown that escins have several biological activities including anti-inflammatory action and inhibitory effects on the absorption of ethanol and glucose. For the edible utilization of the seeds, natural seeds are usually treated with wooden ashes to remove harshness. Here, we found the novel compounds derived from escins in the edible seeds after the food processing with wooden ashes. The instrumental analyses revealed the chemical structures of escins and the derivatives. These compounds are identified as four types of deacetylescins Ia, IIa, Ib, and IIb as well as two types of desacylescins I and II. To determine their biological activity, the purified compounds were tested for their potential nutraceutical activity. The oral glucose tolerance test in mice revealed that a single oral administration of the isolated components of deacetylescins at a dose of 100 mg/kg was clearly effective in attenuating the elevation of blood glucose levels. The inhibitory effects of escins and their derivatives were in the order of escins>deacetylescins>desacylescins. Moreover, we found the inhibitory activity of those compounds on pancreatic lipase. Escins were the most potent in inhibiting the enzyme activity, and followed by desacylescins and then deacetylescins. Taken together, our results suggest the potential usefulness of novel saponins including deacetylescins and desacylescins from edible seeds as novel sources for nutraceutical foods with anti-obese effects.     

In vitro α-amylase and pancreatic lipase inhibitory activity of Cornus mas L. and Cornus alba L. fruit extracts

Less-common fruits from Cornus spp. (Cornaceae), also named dogwoods, have shown antidiabetic, antibacterial and anti-allergic properties and are thus considered a source of phytochemicals that are beneficial to human health. The study aimed to compare the chemical compositions of the aqueous and ethanolic extracts of lyophilized fresh-picked and commercially available dried fruits of Cornus mas (Cm, cornelian cherry) and Cornus alba (Ca) fruits using HPLC-DAD-MS/MS method. Simultaneously, the α-amylase and pancreatic lipase (PL) inhibitory activities of the prepared extracts were compared by in vitro fluorescence assay based on the kinetic hydrolysis of starch or oleate ester of 4-methylumbelliferone (MUO), respectively. Additionally, a bio-assay guided identification of compounds potentially responsible for the inhibition of pancreatic enzymes was performed. Iridoids (loganic acid, cornuside) and anthocyanins (pelargonidin 3-O-galactoside) were identified in the Cm fruit extracts. Flavonoids, such as quercetin and kaempferol derivatives, were detected in the Ca fruit extracts. The chromatographic separation of the constituents of Ca fruit provided a fraction containing phenolic acids derivatives, which inhibited PL activity by 69.9 ± 4.5% at a concentration of 7.5 μg·mL^?1. The IC₅₀ of hydroxytyrosol glucoside, isolated from the most active Ca fraction, was 0.99 ± 0.10 mg·mL^?1 indicating other constituents responsible for the fraction activity. The most active subfraction from Cm fruit (7.5 μg·mL^?1), which inhibited PL activity by 28.3 ± 1.5%, contained pelargonidin 3-O-galactoside. Loganic acid and cornuside in highly pure form did not inhibit lipase activity. The phytochemical constituents of Cm, and particularly of Ca fruit extracts, can inhibit pancreatic enzymes and thus might be considered effective preparations in the prevention and control of hyperlipidemia related diseases.     

山楂饮片对胰脂肪酶活性的抑制作用研究

目的 探讨不同产地、不同品种的山楂样品对胰脂肪酶活性的抑制作用。方法 以对硝基苯基丁酸酯作为底物,在405 nm波长测定山楂饮片样品的水提物对胰脂肪酶体外活性。结果 各批次山楂样品对胰脂肪酶活性具有一定的抑制作用。结论 山楂可用于预防和治疗肥胖症;胰脂肪酶活性可作为山楂饮片等级划分的生物效应指标。     

Inhibitory activities of Puerariae Flos against testosterone 5α-reductase and its hair growth promotion activities

Crude drugs expected to have an estrogenic effect were screened for their inhibitory activity on testosterone 5α-reductase. Testosterone 5α-reductase is an enzyme catalyzing the conversion of testosterone to dihydrotestosterone, which possesses high affinity for the androgen receptor. Among the crude drugs tested, we focused on Puerariae Flos (the flowers of Pueraria thomsonii) due to its potent inhibitory activity and suitability for commercial use. The 50% ethanolic extract of Puerariae Flos (PF-ext) showed inhibitory activity of 60.2% at 500 μg/ml against testosterone 5α-reductase. Interestingly, it was more potent than that of Puerariae Radix (roots of Pueraria lobata). PF-ext also showed in vivo anti-androgenic activity using a hair growth assay in testosterone-sensitive male C57Black/6NCrSlc strain mice. We demonstrated saponins, including soyasaponin I and kaikasaponin III, to be active components in PF-ext. In addition, hair growth promotion activity in C3H/He mice at 2 mg/mouse/day of the topical administration of PF-ext was demonstrated. Thus, Puerariae Flos is a promising crude drug for treating androgenic alopecia.     

Inhibitory effects of compounds isolated from fruit of <Emphasis Type="Italic">Juglans mandshurica</Emphasis> on pancreatic lipase

The water extract of Juglans mandshurica fruit has been shown to strongly inhibit pancreatic lipase in vitro in a dose-dependent manner. The extract was observed to inhibit the normal elevation in the level of plasma triacylglycerol in rats 2–4 h after oral administration of a lipid emulsion. Fourteen compounds isolated from J. mandshurica fruit were evaluated for their inhibitory activity against pancreatic lipase. Of these, 1,4,8-trihydroxynaphthalene-1-O-β-d-[6′-O-(3″,4″,5″-trihydroxybenzoyl)]glucopyranoside (1) showed the strongest inhibitory activity.