Effect of a surfactant, Tween 80, on the formation and secretion of chylomicrons in the rat

Utility of the avian sub-acute dietary toxicity test in ecological risk assessment and a path forward to reduce animal use

The United States Environmental Protection Agency (USEPA) has long required both avian sub-acute dietary and acute oral studies to inform risk assessments for pesticides. Recently, the USEPA collaborated with People for the Ethical Treatment of Animals to determine whether the results of the acute oral avian toxicity test or the sub-acute dietary toxicity test consistently generated the greatest risk predictions in USEPA tier 1 assessments for pesticides first registered between 1998 and 2017. Their study concluded that in 99% of the cases, risk conclusions were driven by the acute oral study (OPPTS 850.2100, OCSPP 850.2100, or similar) because using these data results in higher risk quotients than sub-acute dietary data. Shortly after publishing these results, the USEPA released a formal memorandum providing guidance for waiving the sub-acute dietary study for most pesticides. The USEPA will, however, retain the option to require sub-acute dietary studies for pesticides with certain chemical properties. However, as the avian sub-acute dietary study has an exposure regimen that is often more representative of how birds are exposed to pesticides under actual use conditions than does the acute oral study (i.e., as part of a dietary item eaten over the course of a day and not a bolus dose), this study can provide useful context for risk assessment on a case-by-case basis. Decision criteria are needed to determine a path forward that both minimizes vertebrate animal testing and positions the avian sub-acute dietary data as an option for risk refinement. Decision criteria are proposed here with recommendations for refining the design of avian sub-acute dietary studies to ensure that the data generated are optimized to support a science-based acute avian risk assessment, supported by a case study demonstrating when and how sub-acute dietary studies may be used in a higher-tier risk assessment. Integr Environ Assess Manag 2022;18:1629-1638. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

The underlying rationality of Chinese medicine herb pair Coptis chinensis and Dolomiaea souliei: From the perspective of metabolomics and intestinal function

ETHNOPHARMACOLOGICAL RELEVANCE

The combination of Coptis chinensis (RC) and Dolomiaea souliei (VR) has long been used as a classic herb pair for the treatment of gastrointestinal diseases, but the underlying mechanisms remain unknown.

MATERIALS AND METHODS

In this study, the rationality of evidence-based RC and VR combination was explored from the perspective of metabolism, gut microbiota and gastrointestinal function.

RESULTS

After 5 weeks treatment, VR extracts (700 mg/kg) and RC alkaloids (800 mg/kg) showed no toxic effect on mice. However, RC administration significantly decreased the body weight of mice. Gastric emptying, gastrointestinal motility function and the absorption of FITC dextran were retarded in the mice of RC group, taking RC along with low dose VR (RC-VRL) and high dose VR (RC-VRH) reversed the impaired gastrointestinal function caused by RC. RC administration significantly increased villus height/crypt depth value. Notably, VR administration increased the number of crypts in mice ileum and reduced villus height/crypt depth value in VR and RC combination group. RC treatment significantly increased the expression of occludin compared to NC group; RC-VRL treatment reversed this tendency. While, VR administration increased ZO1 expression by 99.4% compared to NC mice. As for gut microbiota, RC gavage decreased the gut microbiota diversity, but gut microbiota in VR group was similar to NC group, and VR and RC combination increased gut microbiota diversity. RC administration obviously increased the proportion of Akkermansia muciniphila, Bacteroides thetaiotaomicron, Parabacteroides distasonis, and Escherichia coli, compared to NC mice. VR treatment increased the richness of Bacteroides thetaiotaomicron, Parabacteroides distasonis. RC-VRL and RC-VRH treatment dose-dependently increased the richness of Rikenellaceae RC9, Lactobacillus, and decreased the abundance of Psychrobacter, Bacteroides and Ruminococcus in mice. Serum metabolomic analysis revealed that RC gavage significantly down regulated 76 metabolites and up regulated 31 metabolites. VR treatment significantly down regulated 30 metabolites and up regulated 12 metabolites. Weight loss caused by RC may attribute to the elevated methylxanthine level in mice. The potential adverse effects caused by high dose RC intake may partially alleviate by high serum contents of adenosine, inosine and urolithin A resulted from VR coadministration.

CONCLUSION

VR may alleviate RC caused "fluid retention" via normalizing gastrointestinal function, gut microbiota and modulating the perturbed metabolism.

RMD86, a thiophene derivative, promotes antinociceptive and antipyretic activities in mice

Treatment of pain and fever remains an important challenge for modern medicine. Non-steroidal anti-inflammatory drugs (NSAIDs) are the pharmacological options most often used, but their frequent use exposes the patient to serious side effects and dangerous drug interactions. In this context, thiophene derivatives are promising therapeutic alternatives. In this study, we evaluated the in vivo and in silico antinociceptive and antipyretic properties of RMD86, a thiophene derivative. At 100 mg/kg, RMD86 induced no significant changes in the motor coordination of mice in the Rotarod test. At 25, 50, and 100 mg/kg RMD86 significantly reduced the number of abdominal contortions induced by acetic acid (antinociceptive activity) in mice when compared to the control. In the formalin test, for the first phase, there was a reduction in licking times at doses of 50 and 100 mg/kg. In the second phase, reduction occurred at all doses. In the hot plate test, RMD86 (at 100 mg/kg) increased latency time in the first 30 min. For antipyretic activity, RMD86, when compared to the reference drug acetaminophen (250 mg/kg), significantly reduced pyrexia at 30, 60, and 120 min, at dosages of 25, 50 and 100 mg/kg. Molecular docking studies revealed that RMD86 presents a greater number of interactions and lower energy values than both the co-crystallized ligand and the reference drug (meloxicam) against COX-1 and COX-2 isoenzymes. The results give evidence of the analgesic and antipyretic properties like NSAIDs suggesting its potential for pain therapy.

Poloxamer-chitosan-based Naringenin nanoformulation used in brain targeting for the treatment of cerebral ischemia

OBJECTIVE

Here, the aim is to improve the bioavailability of Naringenin (NRG) in brain and to establish the highest remedial benefit from a novel anti-ischemic medicine i.e. NRG.

METHODS

A novel Naringenin-loaded-nanoemulsion (NE)-(in situ)-gel (i.e. thermoresponsive), was formulated with the help of Poloxamer-407 (20.0% w/v). Chitosan (CS, 0.50% w/v) was used to introduce the mucoadhesive property of NE-(in situ)-gel and finally called as NRG-NE-gel + 0.50%CS. A novel UHPLC-ESI-Q-TOF-MS/MS-method was optimized and used for NRG-NE-gel + 0.50%CS to quantify the Pharmacokinetic-(PK)-parameters in plasma as well as brain and to evaluate the cerebral ischemic parameters after MCAO i.e. locomotor activity, grip strength, antioxidant activity, and quantity the infarction volume in neurons with the safety/toxicity of NRG-NE-gel + 0.50%CS after i.n. administration in the rats.

RESULTS

The mucoadhesive potency and gelling temperature of NRG-NE-gel + 0.50%CS were observed 6245.38 dynes/cm2 and 28.3 ± 1.0 °C, respectively. Poloxamer-407 based free micelles size was observed 98.31 ± 1.17 nm with PDI (0.386 ± 0.021). The pH and viscosity of NRG-NE-gel + 0.50%CS were found to be 6.0 ± 0.20 and 2447 ± 24cp (at 35.0 ± 1.0 °C temperature), respectively. An elution time and m/z NRG were observed 1.78 min and 270.97/150.96 with 1.22 min and m/z of 301.01/150.98 for Quercetin (IS) respectively. Inter and intra %precision and %accuracy was validated 1.01-3.37% and 95.10-99.30% with a linear dynamic range (1.00 to 2000.00 ng/ml). AUC0-24 of plasma & brain were observed 995.60 ± 24.59 and 5600.99 ± 144.92 (ng min/ml g) in the rats after the intranasal (i.n.) administration of NRG-NE-gel + 0.50%CS. No toxicological response were not found in terms of mortalities, any-change morphologically i.e. in the microstructure of brain as well as nasal mucosa tissues, and also not found any visual signs in terms of inflammatory or necrosis.

CONCLUSION

Intranasally administered NRG-NE-gel + 0.50%CS enhanced the bioavailability of Naringenin in the brain. In the cerebral ischemic rats, significantly improved the neurobehavioral activity (locomotor & grip strength) followed by antioxidant activity as well as infarction volume. Finally, the toxicity studies carried out and established the safe nature of optimized-NRG-NE-gel + 0.50%CS.

Poloxamer-407 thickened lipid colloidal system of agomelatine for brain targeting: Characterization, brain pharmacokinetic study and behavioral study on Wistar rats

The current study was designed to enhance the brain bioavailability and to extract maximum therapeutic benefit from a novel antidepressant drug, agomelatine. For this purpose, a thermoresponsive in situ gel was prepared by dissolving 20% w/v of Poloxamer-407 in agomelatine containing nanoemulsion. To impart mucoadhesive property, 0.5% w/v concentration of chitosan was ensured in the final formulation, named as Ago-NE-gel+0.5%chitosan. The gelling point and mucoadhesive strength of Ago-NE-gel+0.5%chitosan were found to be 28 ± 1 °C, and 6246.27 dynes/cm² respectively. The size of free micelles of Poloxamer-407 was recorded graphically at 18.43 ± 0.95 nm whereas the size of sterically stabilized Ago-NE was observed at 142.58 ± 4.21 nm. The viscosity and pH of Ago-NE-gel+0.5%chitosan were found to be 2439 ± 23 cP (at 35 ± 1 °C temperature) and 5.8 ± 0.2 respectively. The developed formulation was found safe on nasal mucosa during the toxicity study. CLSM based brain distribution study suggested that Ago-NE-gel+0.5%chitosan is more competent to deliver the drug into the brain as compared to agomelatine-suspension. After intranasal administration of Ago-NE-gel+0.5%chitosan in Wistar rats, the AUC_0-8h in brain and plasma were found to be 1418.591 ± 71.87 and 473.901 ± 32.42 ng.h/ml respectively. The hypothesis conceived at the beginning of this research work was delivered as 2.82 folds enhanced bioavailability of agomelatine in the brain. The behavioral studies confirmed that the antidepressant activity of agomelatine can be improved by loading the drug into a mucoadhesive-nanoemulsion-gel system followed by its intranasal administration.

Oral administration of lipid oil-in-water emulsions performed with synthetic or protein-type emulsifiers differentially affects post-prandial triacylglycerolemia in rats

In this study, we compared the impact of administration of size-calibrated lipid emulsions prepared with either synthetic or natural emulsifiers on the post-absorptive plasma triacylglycerol responses in rats. We did this using four types of size-calibrated (10 μm diameter) and metastable (3 days) emulsions with 20% of an oleic acid-rich sunflower oil and 1% of either synthetic emulsifiers (Tween 80 or sodium 2-stearoyl-lactylate) or two proteins (β-lactoglobulin or sodium caseinate). An oral fat tolerance test was performed in fasted rats by oral administration of each of these formulations in continuous or emulsified forms. Kinetic parameters (AUC_0-inf., AUC_0-6h, C_max, T_max, and T_1/2) for the description of the plasma triacylglycerol responses were calculated. AUC_0-6h and AUC_0-inf. calculated for the protein groups were significantly lower than those of the control and the synthetic groups. These lower values were associated with significant decreases in the C_max, exacerbated by the emulsion form and with marked decreases in the T_max as compared to the control group. T_1/2 values were differentially affected by the lipid administration forms and by the nature of the emulsifiers. As compared with the control group, T_1/2 was largely increased in the sodium stearoyl-2-lactylate group, but on the contrary, largely lowered in the casein group. We concluded that the use of proteins as natural emulsifiers in lipid emulsions decreased the magnitude of post-prandial triacylglycerolemia for the same amount of ingested lipids, when the emulsion size is controlled for. Proteins could be a promising alternative to the widespread use of synthetic emulsifiers in the food industry.

Microbial degradation of endosulfan in contaminated soil with the elution of surfactants

In this work, an endosulfan-degrading strain was isolated from the aged soil contaminated by endosulfan, and identified as Ochrobactrum sp. EB-4 by 16S rDNA sequence analysis. The microbial degradation characteristics of endosulfan in three eluents (Tween 80 + SDS, Tween 80 + Na2SiO3, Tween 80 + SDS + Na2SiO3) were investigated. The results showed that the degradation percents of α-, β-endosulfan in the three eluents were 86.83 %∼92.91 % and 88.90 %∼93.94 % in 15 days, respectively. The degradation process can be well described by the first-order kinetic model, and the half-times of α-endosulfan in eluent 1∼eluent 3 were 3.83, 5.29, and 4.53 days, while those of β-endosulfan were 3.35, 4.50 and 3.79 days, respectively. The endosulfan diol and endosulfan sulfate as main metabolites were detected, and the former can be further degraded by this strain, which revealed that the simultaneously happened hydrolysis and oxidation reactions were the main degradation processes, and dominated by hydrolysis reaction. After 5 days of washing with the eluents, 56.00∼84.33 % of α-endosulfan, and 46.49∼68.56 % of β-endosulfan in soil were eluted, respectively, and can be entirely biodegraded in 12 days, which indicated that the microbial degradation was the rate-determining step.

Tolerable Levels of Nonclinical Vehicles and Formulations Used in Studies by Multiple Routes in Multiple Species With Notes on Methods to Improve Utility

Formulation of nonclinical evaluations is a challenge, with the fundamental need to achieve multiples of the clinical exposure complicated by differences in species and routes of administration-specific tolerances, depending on concentrations, volumes, dosing regimen, duration of each administration, and study duration. Current practice to approach these differences is based on individual experience and scattered literature with no comprehensive data source (the most notable exception being our 2006 publication on this same subject). Lack of formulation tolerance data results in excessive animal use, unplanned delays in the evaluation and development of drugs, and vehicle-dependent results. A consulting firm, a chemical company, and 4 contract research organizations conducted a rigorous data mining operation of vehicle data from studies dating from 1991 to 2015, enhancing the data from this author's 2006 publication (3 of the six 2015 contributors were also 2006 contributors). Additional data were found in the published literature. The results identified 108 single-component vehicles (and 305 combination formulations) used in more than 1,040 studies across multiple species (dog, primate, rat, mouse, rabbit, guinea pig, minipig, pig, chick embryo, and cat) by multiple routes for a wide range of study durations. The tabulated data include maximum tolerated use levels by species, route, duration of study, dose-limiting toxicity where reported, review of the available literature on each vehicle, guidance on syringe selection, volume and pH limits by route with basic guidance on nonclinical formulation development, and guidance on factors to be considered in nonclinical route selection.

Impact of various emulsifiers on ALA bioavailability and chylomicron synthesis through changes in gastrointestinal lipolysis

Formulating healthy food rich in omega 3 fatty acids requires prior knowledge of the parameters influencing their bioavailability and their metabolic fate. In this context, we studied the effects of various emulsifiers widely used in the food industry, on the gastrointestinal lipolysis of flaxseed oil emulsions in an in vitro model and on the intestinal absorption and lymphatic secretion of alpha-linolenic acid (ALA) in rats. In vitro data showed that the emulsification of flaxseed oil with soya lecithin improved the gastric lipolysis of the oil (+30%), while the presence of Tween 80 or of sodium caseinate decreased it (-80% and -40%, respectively). The in vivo data demonstrated that the intestinal absorption and the lymphatic secretion of ALA were improved with soya lecithin (Cmax = 24 mg mL(-1)) and reduced in the presence of sodium caseinate (Cmax = 7 mg mL(-1)) compared to unemulsified flaxseed oil (Cmax = 16 mg mL(-1)); Tween 80 had no effect. In addition, the synthesized chylomicrons were notably larger and more numerous with soya lecithin whereas they were smaller in the presence of sodium caseinate (p < 0.05). This study shows that the intestinal bioavailability of ALA was increased by the emulsification of flaxseed oil with soya lecithin via an improved lipolysis, favouring the intestinal absorption of ALA and the secretion of many large chylomicrons in lymph.

Enhancement of ginsenoside biosynthesis and secretion by Tween 80 in Panax ginseng hairy roots

We evaluated the effect of Tween 80 permeabilization on ginsenoside secretion in Panax ginseng hairy roots. Tween 80 (1.2%, w/v) had no significant effect on hairy root vitality. After a 25-day treatment with Tween 80, approximately 76% of the total ginsenosides was released into the surrounding medium. In the case of control, the ginsenosides secreted into the medium were negligible. Furthermore, when compared with control, the level of total ginsenosides was enhanced by approximately threefold under Tween treatment. Additionally, secretion of the typical ginsenoside monomers including Rb1 , Rg1 , and Re was analyzed, indicating that the most of them were released into the medium. Moreover, it was observed that dammarenediol synthase, a key enzyme involved in ginsenoside biosynthesis, was upregulated at both gene expression and enzyme activity levels. The expression of genes CYP716A47 and CYP716A53v2 encoding Cyt P450 enzymes catalyzing the formation of protopanaxadiol from dammarenediol and protopanaxatriol from protopanaxadiol, respectively, was slightly upregulated. These results clearly demonstrated that Tween 80 could act not only as an efficient permeabilizer to enhance ginsenoside secretion from the hairy roots, but also as an elicitor to promote the biosynthesis of ginsenoside.

Tragopogon porrifolius improves serum lipid profile and increases short-term satiety in rats

Tragopogon porrifolius (white salsify) is an edible plant commonly used in folk medicine in Lebanon and neighbouring countries. This study investigates the effect of the aqueous extract of the aerial part of T. porrifolius on lipemia and appetite regulation using a rat model. Food intake, abdominal fat percentage, blood lipid profile, liver weight and liver enzymes were assessed following 4 weeks of extract intake via drinking water (50, 100, or 250 mg/kg body weight) in standard high-carbohydrate and high-fat dietary conditions. In a separate study, the short term effect of a preload of T. porrifolius extract on food intake was evaluated. Results showed that consumption of the plant extract for a period of four weeks resulted in a marked improvement of the lipid profile (triglycerides, total cholesterol, LDL and HDL cholesterol). Body weight, food intake and intra-abdominal fat were also lower in animals given the plant extract (100 and 250 mg/kg). In addition, T. porrifolius extract preload produced a dose dependent decrease in food intake observed over 24h. The intake of T. porrifolius aqueous extract therefore improved lipemia and increased satiety in rats with no visible adverse effects.

A new function of Vitamin E-TPGS in the intestinal lymphatic transport of lipophilic drugs: enhancing the secretion of chylomicrons

The purpose of this study was to examine whether Vitamin E-TPGS had a function in promoting the secretion of chylomicrons in enterocytes. Therefore, we simulated the human intestinal epithelial cells by Caco-2 cell model to study the effect of Vitamin E-TPGS on the chylomicron secretion in vitro. Meanwhile, chylomicron flow blocking rat model and mesenteric lymph cannulated rat model were used for the studies in vivo to evaluate the effect and probucol was chosen as the model drug. The results of cell experiments indicated that Vitamin E-TPGS at low concentration had a strong enhancement on the secretion of chylomicrons. The results of animal experiments indicated that Vitamin E-TPGS could significantly enhance the lymphatic transport of probucol by the same role consistently with the results obtained from cell experiments. However, the role would reach the plateau and saturate after a concentration dependent increase. These studies first demonstrate the function of Vitamin E-TPGS in the intestinal lymphatic transport of lipophilic drugs, which can significantly promote the secretion of chylomicrons by the intestinal epithelial cells.

Pharmacological evaluation of aqueous extract of Althaea officinalis flower grown in Lebanon

CONTEXT

Althaea officinalis Linn. (Malvaideae) flower is commonly used in folk medicine in Lebanon and neighboring countries. Although most of the studies have been conducted on the mucilage-rich roots, little is known about the flower.

OBJECTIVE

This study investigates the potential role of aqueous extract of Althaea officinalis flower in lipemia, gastric ulcer, inflammation, and platelet aggregation using the rat model.

MATERIAL AND METHODS

Blood lipid profile and liver function were assessed after 1 month of extract intake via drinking water. Anti-inflammatory activity was tested against acute and chronic inflammation induced by carrageenan and formalin, respectively. Antiulcer activity was evaluated using ethanol-induced gastric ulcer. Antiplatelet activity was investigated in vitro using the adenosine 5'-diphosphate (ADP)-induced platelet aggregation bioassay.

RESULTS

The 50 mg/kg body weight dose resulted in significant increase in serum HDL cholesterol level with no effects on stool cholesterol and triacylglycerol. Increasing the dose to 500 mg/kg body weight caused a significant decrease in stool water content. No adverse effect on liver enzymes was observed. Significant anti-inflammatory (acute and chronic inflammation) and antiulcerogenic activities were observed at all used doses (50, 100, and 250 mg/kg body). Time-dependent inhibition of platelet aggregation was demonstrated at 500 µg/ml concentration.

DISCUSSION AND CONCLUSION

The aqueous extract of Althaea officinalis flower demonstrated potential benefits in lipemia, inflammation, gastric ulcer, and platelet aggregation with no visible adverse effect.

Redispersible, dry emulsion of lovastatin protects against intestinal metabolism and improves bioavailability

AIM

To prepare a redispersible, dry emulsion (DE) and investigate whether it can improve intestinal stability and oral absorptive efficiency of the poorly water-soluble lovastatin (Lov).

METHODS

Phosal 53 MCT, Tween 80, and starch sodium octenyl succinate were employed as the oil phase, emulsifying agent, and matrix material, respectively. The redispersible, DE of Lov (Lov-DE) was prepared by spray drying the submicron emulsion of Lov. The characteristics of DE and the in vitro drug release were studied. The protective effects on the metabolism of Lov- DE and reference formulations, including the Lov suspension and the hydroxypropyl-beta-cyclodextrin (CD) complex were investigated in microsomes and the gut wall of male Sprague-Dawley (SD) rats. The bioavailability in SD rats was evaluated simultaneously.

RESULTS

Lov-DE in distilled water was reconstituted compared with the submicron emulsion of Lov before spray drying, and remained almost unchanged after 3 months' storage at room temperature. Compared with the Lov suspension, the in vitro Lov dissolution of both the redispersible, DE and CD complex increased obviously. Compared with control formulations, the metabolism studies carried out in vitro and in vivo confirmed that the redispersible, DE presented remarkable protective effects as indicated by the decreased metabolism rate of Lov. Lov-DE showed a 1.83-fold and 1.44-fold higher the area under the curve(AUC0-8 h)of Lov compared with that of the Lov suspension and CD complex in SD rats, respectively.

CONCLUSION

Lov-DE reduced the metabolism of Lov in the small intestine and improved its oral absorption in SD rats.

Physical and biological considerations for the use of nonaqueous solvents in oral bioavailability enhancement

This review addresses the use of nonaqueous solvents as components of oral formulations in discovery and preclinical studies. Pharmacology, pharmacokinetic, and safety studies are frequently conducted with solution formulations that use a solvent to solubilize poorly aqueous soluble drugs. The physical chemical basis for solubilization and the precipitation of solubilized drug following administration both contribute to the utility of nonaqueous solvent solutions as oral vehicles. While many of these solvents are considered nontoxic, they are not completely inert biologically. The effects of common nonaqueous solvents on the structural integrity of the epithelia, the inherent permeability of and flux across the GI membrane, the activity of efflux and metabolic enzymes, and the effects on GI motility and GI transit times will be described through an examination of available literature. The practical relevance of these factors to the development of early formulations will be examined critically and suggestions made for the suitability of nonaqueous solvents for a variety of purposes.

Nonclinical vehicle use in studies by multiple routes in multiple species

The laboratory toxicologist is frequently faced with the challenge of selecting appropriate vehicles or developing utilitarian formulations for use in in vivo nonclinical safety assessment studies. Although there are many vehicles available that may meet physical and chemical requirements for chemical or pharmaceutical formulation, there are wide differences in species and route of administration specific to tolerances to these vehicles. In current practice, these differences are largely approached on a basis of individual experience as there is only scattered literature on individual vehicles and no comprehensive treatment or information source. This approach leads to excessive animal use and unplanned delays in testing and development. To address this need, a consulting firm and three contract research organizations conducted a rigorous data mining operation of control (vehicle) data from studies dating from 1991 to present. The results identified 65 single component vehicles used in 368 studies across multiple species (dog, primate, rat, mouse, rabbit, guinea pig, minipig, chick embryo, and cat) by multiple routes. Reported here are the results of this effort, including maximum tolerated use levels by species, route, and duration of study, with accompanying dose limiting toxicity. Also included are basic chemical information and a review of available literature on each vehicle, as well as guidance on volume limits and pH by route and some basic guidance on nonclinical formulation development.

Effect of hydroxycut intake on fasted and postprandial lipemia in rats

Hydroxycut, an herbal supplement not currently defined as a drug, is frequently sold over the counter to increase exercise performance, build muscles, and burn fat. The effects of 8 wk of hydroxycut-induced changes on blood lipid profile in rats fed with either regular or high-fat diet were evaluated. Regardless of fat content in the diet, the doses of hydroxycut used significantly decreased fasting serum concentrations of cholesterol, triacylglycerol (TAG), low-density lipoprotein (LDL) cholesterol, total apolipoprotein B (apo B), and LDL/high-density lipoprotein (HDL) cholesterol ratio. A significant increase in serum blood glucose level was observed with hydroxycut intake in the presence of a high-fat diet. No hydroxycut-related changes in serum activities of serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate dehydrogenase (SGPT), lactate dehydrogenase (LDH), and creatinine phosphokinase (CPK) enzymes were noted, indicating no liver damage occurred. A decrease in liver fat content was observed with hydroxycut intake. The drug did not affect the number and composition of secreted very-low-density lipoprotein (VLDL) particles except for a decrease in VLDL TAG when the fat content in the diet was high. Hydroxycut reduced significantly LDL apo B and LDL TAG and cholesterol concentrations. Hydroxycut increased TAG and cholesterol excretion in feces. A single intragastric food load containing hydroxycut reduced significantly postprandial plasma TAG concentration in a dose-dependent manner. In conclusion, hydroxycut intake in recommended doses exerts a beneficial impact on atherosclerosis, an effect attributed to improved clearance and metabolism of lipoprotein particles, and to a lesser extent to an increased excretion of TAG and cholesterol in the feces. More studies are needed to ensure the safety of long-term use of hydroxycut.

Effect of acute and chronic moderate red or white wine consumption on fasted and postprandial lipemia in the rat

The effects of acute and chronic (10 wk) red or white wine consumption on fasted and postprandial lipemia in the rat model are reported. Fasted rats, in the acute study, were loaded intragastrically with 5 ml of an olive oil emulsion (30% w/v) in the presence or absence of wine (8% v/v ethanol), and either mesenteric lymph or blood was collected 3 h postprandially. Animals in the chronic study received either red or white wine in drinking water for a period of 10 wk (3% v/v ethanol). Blood samples were collected from animals in either the fasted state or after fat-wine loading. Postprandially, wine delayed gastric emptying, reduced lymph triacylglycerol (TAG) secretion concomitantly with increased number and decreased chylomicron (CM) size, and increased plasma TAG and CM concentrations. Phospholipid and cholesterol contents of CM, but not very-low-density lipoprotein (VLDL), were increased, indicating enhanced liver bile secretion; however, a significant increase in plasma VLDL concentration was observed. In the chronic study, a wine-fat load resulted in increased high-density lipoprotein (HDL) cholesterol concentration and less pronounced postprandial hypertriglyceridemia and hyperchylomicronemia. In the fasted state, plasma TAG and total apolipoprotein B concentrations were not modified in these animals, and an increase in HDL and a decrease in low-density lipoprotein (LDL)/HDL cholesterol ratios were observed. No liver function or intestinal lipid absorption impairment was observed. In conclusion, unlike binge drinking, chronic moderate wine consumption appears to have a cardioprotective effect in the fasted state, an effect attenuated by the observed temporary postprandial hyperchylomicronemia and hypertriglyceridemia resulting from a direct effect of alcohol on CM size and number.

Effect of Urtica dioica extract intake upon blood lipid profile in the rats

Aqueous (150 mg/kg/day) and to a lesser extent petroleum ether (20 mg/kg/day) extract of Urtica dioica given for 30 days to rats fed with normal or high-fat diet, improved the blood lipid profile. Significant decreases in total cholesterol, LDL cholesterol, LDL/HDL cholesterol ratio and plasma total apo B were observed. Assessment of GOT, GPT and LDH activities showed that no liver damage has occurred during the study period.

Effect of different surfactants in biorelevant medium on the secretion of a lipophilic compound in lipoproteins using Caco-2 cell culture

The impact of a pharmaceutical relevant metabolizable, ionic surfactant or two synthetic, nonionic surfactants on the absorption and lipoprotein incorporation of a lipophilic drug, retinol, was studied in the Caco-2 cell culture. Filter-grown monolayers of Caco-2 cells were incubated for 20 h with (3)H-retinol and (14)C-oleic acid and with increasing concentrations of lyso-phosphatidylcholine (lyso-PC), Cremophor RH40, or Tween 80. The concentration of (3)H-retinol and (14)C-lipid was measured in the apical, intracellular, and basolateral compartments. The basolateral medium was ultracentrifugated into different lipoprotein classes and their (3)H-retinol and (14)C-lipid concentrations were determined. The cells incubated with lyso-PC and Tween 80 increased the incorporation of (3)H-retinol and (14)C-lipid into chylomicrons and very low density lipoproteins (VLDL). The explored surfactants impacted the incorporation of (3)H-retinol and (14)C-lipid in chylomicrons and VLDL in a concentration-dependent manner. As these surfactants interfere with the intestinal lipoprotein secretion, inclusion of high concentrations of the surfactants in lipid-based formulations of poorly aqueous soluble drugs might impact the degree of intestinal lymphatic transport of the drug after oral administration.

Size and number of lymph particles measured by a particle sizer during absorption of structured oils in rats

Chylomicrons transport absorbed fat from the intestine to the circulation. During dietary fat absorption, the chylomicrons become larger in diameter, and in some studies an increase in chylomicron number has been observed as well. In the present study, we compared particle size and number in rat lymph following administration of four different oils. We administered fish oil, medium-chain TAG (MCT), and two structured oils differing in intramolecular structure, with either medium-chain FA in the outer positions of the TAG and long-chain n-3 PUFA in the sn-2 position (MLM oil) or with the reverse structure (LML oil), to lymph-cannulated rats and collected lymph in fractions for the following 8 h. Chylomicron size was measured by a particle size analyzer immediately after collection, and from these data the number of chylomicrons present was estimated. The number of particles in lymph increased during the absorption of oils containing long-chain PUFA (MLM, LML, and fish oil), whereas it was not affected by administration of MCT. The FA from MCT were probably absorbed via the portal vein; therefore, only a small number of particles were measured in lymph. When comparing the two structured oils, we observed a tendency toward a higher number of particles after LML administration, although the difference was not statistically significant. The highest number of particles after administration of all oils was observed in the size intervals 53-80 and 80-121 nm and probably represented small chylomicrons. Thus, the FA composition influenced the number of particles in lymph during absorption, whereas TAG structure had only a minor influence.

Effect of acute and chronic moderate alcohol consumption on fasted and postprandial lipemia in the rat

Effects of acute and chronic alcohol intake on fasted and postprandial lipemia in the rat model are reported. In the acute study, fasted rats are loaded with a 30% w/w olive oil emulsion with or without 8% alcohol in the form of ethanol, beer or whisky. After 3 h, either mesenteric lymph or blood is collected and the TAG-rich lipoprotein fractions are isolated. In the chronic study, animals received, for a period of 10 weeks, 3% alcohol in drinking water in the form of ethanol, beer or whisky. Blood samples were collected from animals in either the fasted state or after being loaded with the fat load as described above. Alcohol ingestion along with a fat load increases the number (increased net apoB48 secretion) and reduces the size (reduced TAG/apoB48 ratio) of CM secreted into the mesenteric lymph duct. It also delays gastric emptying, reduces trans-enterocyte TAG flux rates and increases plasma concentrations of TAG, cholesterol and CM. Similar conditions also results in increased total phospholipid and cholesterol content of CM but not of VLDL, indicating an enhanced liver bile secretion into the gut; however, a significant increase in plasma VLDL concentration is observed. Unlike the acute study, an alcohol-fat load in animals put on chronic alcohol intake results in increased HDL cholesterol concentrations and less pronounced postprandial hypertriglyceridemia and hypercholesterolemia but not hyperchylomicronemia. In the fasted state, plasma TAG and total apoB concentrations are not modified in these animals, and an increase in HDL and a decrease in total and LDL cholesterol concentrations are observed. No liver function impairment is observed following the 10-week period of chronic alcohol intake. In conclusion, unlike binge drinking, chronic moderate alcohol consumption appears to have a cardioprotective effect in the fasted state, an effect attenuated by the observed temporary postprandial hyperchylomicronemia and hypertriglyceridemia resulting from a direct effect of alcohol on CM size and number.