Fat Infusion Research Articles

Testosterone enhances adipose tissue-blood pressure axis in obese mice exposed to early life stress

Previously, we have shown that male and female mice exposed to maternal separation and early weaning (MSEW), a model of early life stress, display exacerbated obesity-induced hypertension in response to chronic high fat diet. However, only male mice showed higher sympathetic tone at baseline, along with increased neuronal activation in PVN and pressor response to the acute stimulation of TRVP1 channels with capsaicin, a mechanism known as adipose afferent reflex (AAR). The aim of this study was to investigate whether obese male MSEW mice show 1) increased intracellular calcium in response to capsaicin in neuronal cultures of dorsal ganglia root (DRG), and 2) a role for sex hormones in AAR reactivity in vivo. Six-months-old control and MSEW fed a high fat diet (HFD, 60% kcal fat) were injected with pAAV-CAG-tdTomato (59462-PHP.S, 1012 viral particles); 8 sites; 4 ul/site; bilateral). After 6 weeks, mice were decapitated and DRGs (L5-T12) were collected and placed in ice-cold HBSS solution, dissociated and mixed with Collagenase P (1 mg/ml in HBSS, 15 min, 37 oC). After 0.25% Trypsin-EDTA incubation, neurons were mechanically dissociated, collected by centrifugation and resuspended in DMEM-10% FBS, plated onto the Matrigel Basement Membrane Matrix covered coverslips and maintained at 37 oC for 15-16 hours. Neuronal cultures were incubated in Ca2+ imaging solution with 2 μM Fura-2 AM, 30 min in dark conditions. After de-estirification, intracellular Ca2+ transients were visualized by exciting Fura-2 at 340 ± 20 nm and 380 ± 20 nm using a high-speed filter changer to obtain a ratiometric value independent of indicator concentration. Emitted light was passed through a dichroic filter (400-nm high pass) and an emitter filter (520 ± 30 nm) and was digitized onto the sensor of an EMCCD camera. Background subtraction and normalization to baseline were used to quantify changes in fluorescence. Despite similar resting uncalibrated ratios of calcium levels between groups (~0.6 ratio units, n=3), sensory neurons from MSEW mice tended to display larger responses to capsaicin (50 uM), showing elevated calcium kinetics vs. controls (0.56±0.09 vs. 0.31±0.12 delta ratio, respectively, p=0.063) as well as longer transients, perhaps indicative of reduced clearance or buffering. A separate set of age-matched mice were gonadectomized. After 4 weeks, anesthetized mice were fitted with carotid artery catheter for direct blood pressure measurement in response to the infusion of perigonadal fat with capsaicin (1.5 pmol/μL during 2 minutes in 4 sites, bilaterally). Capsaicin-induced pressor response was exacerbated in intact MSEW male mice compared to intact controls (9.0±0.2 vs. 1.3±0.2 delta mmHg, respectively, n=6, p<0.05). Orchidectomy attenuated delta blood pressure in MSEW mice to 7.0±0.2 mmHg (p<0.05 vs. intact MSEW), while enhanced delta blood pressure in control mice to 7.5±0.2 mmHg (p<0.05 vs. intact control). MSEW did not influence the pressor response to perigonadal fat stimulation with capsaicin either in intact or ovariectomized obese female mice (n=4-6 per group, p>0.05), suggesting that estradiol may not to play a protective role in obese females AAR reactivity. This data indicates that testosterone could buffer the AAR reactivity of obese control mice, while MSEW exerts an opposite effect. Thus, investigating testosterone signaling on calcium handling mechanisms (i.e., buffers, pumps, ER-mediated calcium release) in sensory neurons innervating visceral fat will provide insights on the sex-specific contribution of afferent sympathoexitatory signals to obesity-hypertension in male MSEW mice. This study was supported by NIH R01 HL135158, and SALT pilot - University of Kentucky to ASL. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

β-Cell Insulin Resistance Plays a Causal Role in Fat-Induced β-Cell Dysfunction In Vitro and In Vivo.

In the classical insulin target tissues of liver, muscle, and adipose tissue, chronically elevated levels of free fatty acids (FFA) impair insulin signaling. Insulin signaling molecules are also present in β-cells where they play a role in β-cell function. Therefore, inhibition of the insulin/insulin-like growth factor 1 pathway may be involved in fat-induced β-cell dysfunction. To address the role of β-cell insulin resistance in FFA-induced β-cell dysfunction we co-infused bisperoxovanadate (BPV) with oleate or olive oil for 48 hours in rats. BPV, a tyrosine phosphatase inhibitor, acts as an insulin mimetic and is devoid of any antioxidant effect that could prevent β-cell dysfunction, unlike most insulin sensitizers. Following fat infusion, rats either underwent hyperglycemic clamps for assessment of β-cell function in vivo or islets were isolated for ex vivo assessment of glucose-stimulated insulin secretion (GSIS). We also incubated islets with oleate or palmitate and BPV for in vitro assessment of GSIS and Akt (protein kinase B) phosphorylation. Next, mice with β-cell specific deletion of PTEN (phosphatase and tensin homolog; negative regulator of insulin signaling) and littermate controls were infused with oleate for 48 hours, followed by hyperglycemic clamps or ex vivo evaluation of GSIS. In rat experiments, BPV protected against fat-induced impairment of β-cell function in vivo, ex vivo, and in vitro. In mice, β-cell specific deletion of PTEN protected against oleate-induced β-cell dysfunction in vivo and ex vivo. These data support the hypothesis that β-cell insulin resistance plays a causal role in FFA-induced β-cell dysfunction.

1515-P: Effect of Aging on Insulin Clearance in Mice

Aging is commonly linked with hyperinsulinemia and insulin resistance. Age-related hyperinsulinemia results from increased insulin secretion and/or decreased insulin clearance as compensatory mechanisms to peripheral insulin resistance. Several studies have reported reduced β-cell function in elderly rodents and humans. Earlier reports on decreased insulin clearance due to aging suggest that hyperinsulinemia in elderly could be explained predominantly by a reduction in insulin clearance. Hence, we aim to better understand the role of aging on insulin clearance following fat infusion. To investigate the aging effect, 3 months and 10-14 months old C57BL6 mice were infused with ethylpalmitate for 48h (hydrolyzed to palmitate and ethanol in plasma), to achieve elevated circulating FFA in a non-toxic manner. Mice were then subjected to hyperglycemic clamp, and during the clamp plasma C-peptide and insulin were measured to evaluate insulin clearance. Glucose infusion rate (GINF), insulin sensitivity index (SI) and disposition index (DI) were also assessed during clamp analysis. GINF is a measure of glucose tolerance whereas DI evaluates β-cell function. Whereas insulin secretion did not increase, insulin clearance was reduced in the aging mice, as indicated by the lower C-peptide/insulin molar ratio, observed during hyperglycemic clamp. No significant changes were observed in GINF between old and young mice; however, SI and DI were lower in elderly group. These results collectively suggest that with advancing age, β-cells may lose their ability to maintain a higher insulin secretion and that reduced hepatic insulin clearance plays a more dominant role to compensate for age-related decline in insulin sensitivity. Disclosure S.Rahman: None. S.Zaidi: Other Relationship; BullFrog AI. H.T.Muturi: None. S.M.Najjar: None. A.Giacca: None.

Lipid Infused into the Duodenum of Rats at Varied Rates Influences Food Intake and Body Weight Gain

We investigated the influence of luminal fat, including intestinal exposure time to fat, on food intake and body weight (BW) gain under conditions that resemble normal feeding. Male Wistar rats were divided into three groups: two groups received 30 mL Intralipid® and one group received 30 mL saline, in addition to having access to a nonfat diet. The saline-infused and one of the fat-infused groups were schedule fed (SF), i.e., allowed to eat for 7 h of the dark cycle; the other fat-infused group had diet available for 24 h. The three groups of rats were subdivided further by rate of infusion, i.e., 0.13 mL/min or 1.0 mL/min for a total of 6 groups. Rats infused with fat had lower BW gain than saline controls, except when diet was available for 24 h and rate of fat infusion was 1.0 mL/min (BW gain was similar to saline group). Daily energy intake corresponded to BW gain data. Pancreata and intestinal mucosa were examined (after 2 wk of treatment) for hypertrophic changes that may be related to specific factors stimulated by luminal fat; these may also be involved in the control of food intake. Rats infused with fat had heavier pancreata than saline-infused rats, and infusion of fat at 0.13 mL/min resulted in heavier pancreata than infusion at the faster rate. DNA and protein analysis indicated that hypertrophy rather than hyperplasia was responsible for this effect. Thus, prolonged fat exposure to intraluminal receptors resulted in reduced total daily energy intake, suppressed BW gain and heavier pancreata. The combined data support a connection among intraluminal fat, negative feedback signals that inhibit food intake and factor(s) associated with pancreatic stimulation.

Assessment Of Dietary Practices Among Post Covid-19 Patients

Nutritional guidelines for post covid-19 nutrition in both male and female for different age group, in relation to their lifestyle and attitude on covid-19. Objective: To learn about the nutritional behaviors of people who got infected with covid-19. To assess the nutritional intake of people after recovery with covid-19. To assess the relationship of good nutrition and fast recovery Post covid-19. Methods: A cross sectional study was carried out through an online survey on WhatsApp. 100 participants; both male and female were selected through non-probability convenient technique. Participants were assessed through questionnaire. Individuals above 18 years who have been recovered from COVID-19 were the part of this study. Results: Out of 100 participants, 33 had increased appetite, 23 had suppressed appetite and 44 had healthy appetite. 49% participants had infusion of healthy fats, 45 participants were not taking any supplements during their recovery, 62 participants were dehydrated. Fruits and vegetables consumption among participants on daily basis was 39% and their dairy and dairy products consumption was 75%. Conclusions: Appropriate and healthy eating habits have been found to be advantageous in recovering from COVID-19 and in individuals who have recovered from COVID-19.

Review: Influence of postabsorptive metabolism on essential amino acid partitioning in lactating dairy cows

In the lactating cow, essential amino acids (EAAs) absorbed from the gut are partitioned to mammary and extra-mammary tissues via blood plasma circulation. There is also entry of EAA into plasma from the breakdown of proteins in the cow’s body. A balance model across plasma was solved to integrate entry rates of branched-chain (BCAA) and non-branched-chain EAA (NBAA) with their corresponding rate constants for clearance by mammary glands and the remainder of the body, for selected glucose and fat infusion experiments. Endogenous EAA entry from whole-body proteolysis was reduced by glucose and unchanged or increased by fat, the efficiency of net plasma BCAA clearance by mammary and extra-mammary tissues was elevated by glucose but slightly reduced by fat, and the efficiency of extra-mammary NBAA clearance may have decreased during glucose infusion but it was not affected or slightly increased by fat. These differences between glucose and fat responses can be accounted for by insulin and glucagon. Insulin suppresses endogenous EAA entry through mechanistic target of rapamycin complex 1, integrated stress response, and glycogen synthase kinase 3 signaling networks in skeletal muscle. While these networks can also regulate protein synthesis rates in muscle and the extra-mammary body, they exhibit low sensitivities to insulin in lactating ruminants. However, in the mammary glands, via these same networks, insulin stimulates clearance of EAA from plasma, although the drive to maintain a set point for milk protein yield takes precedence over nutritional signals. The glucose-induced increase in mammary BCAA clearance without an effect on NBAA clearance is due to a pronounced decrease in plasma BCAA concentrations. Because NBAAs do not experience a similar decline in concentration, the BCAA effect must be due to their metabolic transformation as opposed to sequestration in proteins. In adipose, the products of BCAA catabolism are lipogenic precursors. We propose that faster lipogenesis in adipose tissue, stimulated by glucose infusion, also promotes the uptake of precursor BCAA from plasma, causing a drop in their circulating concentrations. In addition, insulin stimulates BCAA oxidation in muscle as an alternative fuel to fatty acids. A lower efficiency of extra-mammary NBAA clearance during glucose infusion may be the consequence of decreased hepatic expression of AA-catabolizing enzymes in response to low glucagon concentration. The proportion of EAA entry partitioned to the mammary glands is a culmination of regulatory shifts at all of the points discussed above according to a regulated or unfair competition between mammary and extra-mammary processes.

Fats and Sugars Recruit Distinct Gut‐Brain Circuits To Control Food Intake And Reward

The high‐fat high‐sugar food environment has been implicated as a driver of the obesity epidemic. Nodose ganglia (NG) neurons transmit post‐ingestive signals, including fat and sugar intake, from the gut to the brain. Previous data revealed distinct vagal circuits are required for post‐ingestive fat and sugar reinforcement, but whether these signals converge onto overlapping reward circuits is unclear.MethodsTo address this, we used FosTRAP mice to genetically label whole‐brain neuronal responses to discreet time‐restricted stimuli. Using genetic‐encoded reporter (tdTom) expression and cFos immunolabeling we compared neural responses to intragastric stimuli at two separate timepoints in the same animal.ResultsRepeated intragastric infusion of the same macronutrient resulted in high colocalization between tdTom and cFos labeling (>70%) in neurons of a previously identified gut‐reward circuit (NTS, PBN, SNc, dorsal striatum). Equicaloric infusion of fat or sugar at two separate timepoints significantly reduced colocalization of tdTom and cFos labeling (<30%), suggesting that fat and sugar recruit parallel but largely distinct reward circuits. Viral‐mediated caspase ablation of sugar‐sensing NG neurons abolished activation of the reward circuitry for sugar, but not fat; confirming this is a vagally‐mediated mechanism. Optogenetic stimulation of fat‐sensing NG neurons is sufficient to condition operant behavior. Microdialysis in response to equicaloric intragastric infusions of fat or sugar resulted in similar dopamine efflux in the dorsal striatum. To obtain the same level of dopamine efflux, more calories of an equicaloric fat‐sugar combination are required, correlating with compensatory increased intake of fat‐sugar solution.ConclusionThere are labeled lines for vagally‐mediated fat or sugar reward. Reduced reward in response to fat‐sugar combinations may explain the inclination to overindulge in high‐fat high‐sugar foods, and have broad implications for the pathogenesis of obesity.

Asymmetric Control of Food Intake by Left and Right Vagal Sensory Neurons

Gut‐innervating vagal sensory neurons residing in the nodose ganglia (NG) conveys meal‐borne signals and control food intake, however, the underlying gut‐brain neurocircuit is unclear. The neuropeptide cocaine‐ and amphetamine‐regulated transcript (CART) is expressed in a subpopulation of vagal sensory neurons (~40%) that innervate the whole length of the gut and its release in the NTS is sufficient for meal termination. Thus, it can be an excellent target to understand the role of sensory neurons in feeding. Emerging evidence suggests that right or left NG (LNG or RNG) neurons recruit different downstream central circuits to control feeding, but the mechanisms remain poorly understood. Our hypothesis is that LNGCART and RNGCART neurons sense different meal‐related signals and are necessary and sufficient to modulate feeding.MethodsIn vivo calcium imaging, viral neuronal tracing, and feeding behaviors were assessed in response to chemo‐ and opto‐genetic stimulation of gut‐innervating vagal sensory neurons using CARTcre mice.ResultsAnatomical tracing revealed that LNGCART and RNGCART neurons innervate different regions of the duodenum (n=3). LNGCART innervate the muscular layer, while RNGCART innervate the villi. Importantly, 2‐photon calcium imaging highlighted real time increased activity in LNGCART in response to stretch, while intraduodenal fat infusions preferentially increased RNGCART neuron activity (n=7/group). Mice with LNGCART neurons ablation consumed higher volumes of liquid meal indicative of attenuated response to gastric and intestinal distension (n=6‐7/group). Furthermore, chemogenetic stimulation of LNGCART, but not RNGCART, caused pronounced and sustained hypophagia (n=7/group). Interestingly, mice with chemogenetic activation of RNGCART, but not LNGCART, increased flavor conditioning (n=7/group), while ablation of RNGCART neurons abolished the conditioned flavor preference that was paired with intragastric fat infusion (n=7/group) supporting their role in reward. In addition, optogenetic stimulation of RNGCART promoted self‐stimulation in a nose poke task (n=4). Lastly, dopaminergic neurons of the substantia nigra increased their firing rate in response to intraduodenal fat infusion, but not duodenal distension (n=2/group).ConclusionLeft and right vagus nerves provide different sensory information about a meal to the brain. Both anatomical and behavioral feeding studies support the necessity and sufficiency LNGCART neurons as food quantity detectors and RNGCART neurons as food reward mediators ‐ which has less influence on how much is consumed but rather plays a role in the decision‐making process about which foods to consume. Our findings on asymmetrical vagal innervation of the gut provides new mechanistic insight for how feeding decisions are made in response to vast and complex meal‐related signals.

A clinical study of using a phentolamine alcohol wet dressing in the treatment of extravasation after a 20% fat emulsion intravenous infusion - a randomised trial

Introduction/Objective. The aim of our paper was to investigate the clinical efficacy of using a phentolamine alcohol wet dressing to treat the extravasation of an intravenously administered infusion of milk fat. This study was designed as a randomized trial, and was done at the Hengshui people?s Hospital, Hebei Province, China, from June 2019 to June 2020. Methods. In total, 300 patients were randomly divided into two groups. In the experimental group, the patients were treated using a phentolamine alcohol wet dressing, whereas in the control group, the patients were treated using a hydropathic compress with a 50% magnesium sulphate solution. The cure rate, healing time, and patient satisfaction of the two groups were compared and analyzed. Results. The cure rate of intravenous infusion extravasation was 92.67% (139/150) in the experimental group and 70.67% (106/150) in the control group (p < 0.05). In the experimental group, there were 66 patients whose cure time was less than 24 hours, 62 patients whose cure time was between 24 and 48 hours, and 22 patients whose cure time was over 48 hours. The cure time of the patients was significantly shorter in the experimental group than the control group. After treatment, in the experimental group, 67 patients were very satisfied, 52 patients were satisfied, 21 patients were generally satisfied, and 10 patients were dissatisfied; in the control group, 32 patients were very satisfied, 40 patients were satisfied, 56 patients were generally satisfied, and 22 patients were dissatisfied. The satisfaction of patients was significantly higher in the experimental group than in the control group. Conclusion. The effect of using a phentolamine alcohol wet dressing to treat the extravasation of an intravenous infusion of milk fat is significantly better than the effect of using a magnesium sulphate solution, and this type of dressing is worthy of clinical application.

Comparative Effects of Intraduodenal Glucose and Fat Infusion on Blood Pressure and Heart Rate in Type 2 Diabetes.

The interaction of nutrients with the small intestine modulates postprandial cardiovascular function. Rapid small intestinal nutrient delivery may reduce blood pressure markedly, particularly in patients with type 2 diabetes (T2DM). Postprandial hypotension occurs in ~30% of patients with longstanding T2DM, but there is little information about the cardiovascular effects of different macronutrients. We compared the blood pressure and heart rate responses to standardized intraduodenal glucose and fat infusions in T2DM. Two parallel groups, including 26 T2DM patients who received intraduodenal glucose infusion and 14 T2DM patients who received intraduodenal fat, both at 2 kcal/min over 120 min, were compared retrospectively. Blood pressure and heart rate were measured at regular intervals. Systolic blood pressure was stable initially and increased slightly thereafter in both groups, without any difference between them. Diastolic blood pressure decreased in response to intraduodenal glucose, but remained unchanged in response to lipid, with a significant difference between the two infusions (P = 0.04). Heart rate increased during both intraduodenal glucose and lipid infusions (P < 0.001 each), and the increment was greater in response to intraduodenal fat than glucose (P = 0.004). In patients with T2DM, intraduodenal fat induced a greater increase in heart rate, associated with a diminished reduction in blood pressure, when compared with isocaloric glucose. The macronutrient composition of meals may be an important consideration in T2DM patients with symptomatic postprandial hypotension.

Increased myocardial fat supply improves cardiac energetics and function in heart failure

Abstract Introduction The failing heart is starved of energy, in part accounting for its contractile dysfunction. Reduced uptake of fat and sugar required for energy production has frequently been demonstrated in heart failure, therefore altering metabolism of glucose and/or fat is therefore attractive as a therapy. We hypothesized increasing glucose supply would be beneficial over increasing fat supply so measured ATP usage (via PCr/ATP ratio and flux through creatine kinase) and cardiac function during fat emulsion infusion or euglycaemic hyperinsulinaemic clamp. Methods 11 patients with a diagnosis of heart failure and nonischaemic cardiomyopathy were recruited, mean age 66 (range 49–80), mean BMI 27.7 (range 21.3–37.5), F:M 3:8, 3 diabetic and 8 non-diabetic. On the first visit they had a baseline cardiac magnetic resonance (CMR), collecting cardiac volumes and function, then were randomised to receive either fat infusion or euglycaemic clamp. Following an hour of infusion, CMR was repeated followed by 31P cardiac magnetic resonance spectroscopy, then a dobutamine stress sequence at 65% maximum heart rate. They received the alternate infusion at the next visit. Results Data was normally distributed. Baseline ejection fraction was 37±9%. PCr/ATP ratio was greater with the fat infusion compared to euglycaemic clamp (1.82±0.26 vs 1.68±0.24, p=0.04). Fat emulsion infusion also brought about a greater ejection fraction increase over the baseline, compared to the euglycaemic clamp in which there was little difference (+5.3±5.3% vs −0.6±3.1%, p=0.004). Calculated cardiac work was greater in the fat infusion group than the Insulin/glucose group (682±156 L.mmHg/min vs 581±85 L.mmHg/min, p=0.009). There was no significant difference in creatine kinase first order rate constant (fat infusion 0.2±0.09/s vs euglycaemic clamp 0.16±0.07/s, p=0.32) nor creatine kinase flux (fat infusion 1.85±0.92 μmol/g/s vs euglycaemic clamp 1.46±0.58 μmol/g/s, p=0.22). The increment in cardiac output on stress over baseline was not significantly different between arms (fat infusion +3.39±3.07 L/min vs euglycaemic clamp +3.08±2.57 L/min, p=0.42). The PCr/ATP ratio showed positive correlation with the stress ejection fraction (R2=0.656, p=0.001), but not with resting ejection fraction. Conclusions Increased supply of fat to the myocardium brought about improved contractility and cardiac energetics compared to an increased glucose supply. The increase in PCr/ATP ratio would imply (given ATP concentrations are kept constant in the myocardium) there is a greater availability of phosphocreatine, suggesting increased mitochondrial ATP synthesis. These results were unexpected as it has traditionally been thought that increased glucose metabolism would yield greater cardiac function in the failing heart. These data suggest targeting myocardial fat metabolism may provide novel treatments for cardiac dysfunction. Figure 1 Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): British Heart Foundation

Intact vagal gut-brain signalling prevents hyperphagia and excessive weight gain in response to high-fat high-sugar diet.

AimThe tools that have been used to assess the function of the vagus nerve lack specificity. This could explain discrepancies about the role of vagal gut‐brain signalling in long‐term control of energy balance. Here we use a validated approach to selectively ablate sensory vagal neurones that innervate the gut to determine the role of vagal gut‐brain signalling in the control of food intake, energy expenditure and glucose homoeostasis in response to different diets.MethodsRat nodose ganglia were injected bilaterally with either the neurotoxin saporin conjugated to the gastrointestinal hormone cholecystokinin (CCK), or unconjugated saporin as a control. Food intake, body weight, glucose tolerance and energy expenditure were measured in both groups in response to chow or high‐fat high‐sugar (HFHS) diet. Willingness to work for fat or sugar was assessed by progressive ratio for orally administered solutions, while post‐ingestive feedback was tested by measuring food intake after an isocaloric lipid or sucrose pre‐load.ResultsVagal deafferentation of the gut increases meal number in lean chow‐fed rats. Switching to a HFHS diet exacerbates overeating and body weight gain. The breakpoint for sugar or fat solution did not differ between groups, suggesting that increased palatability may not drive HFHS‐induced hyperphagia. Instead, decreased satiation in response to intra‐gastric infusion of fat, but not sugar, promotes hyperphagia in CCK‐Saporin‐treated rats fed with HFHS diet.ConclusionsWe conclude that intact sensory vagal neurones prevent hyperphagia and exacerbation of weight gain in response to a HFHS diet by promoting lipid‐mediated satiation.

Fabrication and Characterisation of Lavender Oil and Plant Phospholipid Based Sumatriptan Succinate Hybrid Nano Lipid Carriers

Background: Nanostructured Lipid Carriers (NLCs) of Sumatriptan Succinate (SS) were prepared by using lavender oil. In ancient days, lavender oil was used for the treatment of a migraine. The natural anti-migraine agent, lavender oil, combined with an anti-migraine drug such as SS in a nano-formulation, will be a practical alternative approach in migraine therapy.&#x0D; Objectives: Of sumatriptan succinate were fabricated by using a natural anti-migraine oil (lavender oil), LECIVA-S70, which is a specialized grade for liposomal dermatological preparation and designed for emulsion, fat infusions, nutraceutical formulations, and parenteral use. It contains 70% phosphatidylcholine, which is not generally present in the regular soy lecithin.&#x0D; Methods: The central composite design technique was used to examine the relationship between independent variables and responses such as lavender oil and LECIVA-S70. The dependent variables were Z-average (R1), Polydispersity Index (PDI) (R2), and % entrapment efficiency (R3). The NLCs were prepared with the double emulsification technique. The Fourier transform infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry analyzed the drug excipient compatibility profile. The developed NLCs were characterized for particle size by using Mastersizer, Zetasizer, and Transmission Electron Microscopy TEM). The membrane diffusion technique studied the in vitro drug release profile.&#x0D; Results: The Mean±SD size of the NLCs ranged from 411.4±311.1 d.nm to 398.8±242.6 d.nm. The best formulation (SNE9) demonstrated an average diameter of 398.8±242.6 d.nm, with the PDI of 0.216, and zeta potential of 17.18 mV&#x0D; Conclusion: The optimized formula demonstrated the narrow size range, a satisfactory zeta potential, high drug loading, and reproducible drug release profile. The NLCs successfully retained the aroma of the lavender oil. According to ANOVA, the PDI (R2) is significant with the central composite design.

Role of endogenous glucagon-like peptide-1 enhanced by vildagliptin in the glycaemic and energy expenditure responses to intraduodenal fat infusion in type 2 diabetes.

To evaluate the effects of the dipeptidyl peptidase-4 (DPP-4) inhibitor vildagliptin on glycaemic and energy expenditure responses during intraduodenal fat infusion, as well as the contribution of endogenous glucagon-like peptide-1 (GLP-1) signalling, in people with type 2 diabetes (T2DM). A total of 15 people with T2DM managed by diet and/or metformin (glycated haemoglobin 49.3 ± 2.1 mmol/mol) were studied on three occasions (two with vildagliptin and one with placebo) in a double-blind, randomized, crossover fashion. On each day, vildagliptin 50 mg or placebo was given orally, followed by intravenous exendin (9-39) 600 pmol/kg/min, on one of the two vildagliptin treatment days, or 0.9% saline over 180 minutes. At between 0 and 120 minutes, a fat emulsion was infused intraduodenally at 2 kcal/min. Energy expenditure, plasma glucose and glucose-regulatory hormones were evaluated. Intraduodenal fat increased plasma GLP-1 and glucose-dependent insulinotropic polypeptide (GIP), insulin and glucagon, and energy expenditure, and decreased plasma glucose (all P < 0.05). On the two intravenous saline days, plasma glucose and glucagon were lower, plasma intact GLP-1 was higher (all P < 0.05), and energy expenditure tended to be lower after vildagliptin (P = 0.08) than placebo. On the two vildagliptin days, plasma glucose, glucagon and GLP-1 (both total and intact), and energy expenditure were higher during intravenous exendin (9-39) than saline (all P < 0.05). In well-controlled T2DM during intraduodenal fat infusion, vildagliptin lowered plasma glucose and glucagon, and tended to decrease energy expenditure, effects that were mediated by endogenous GLP-1.

Abstract P3011: Role of CD36 in Insulin Mediated Microvascular Vasodilation in African Americans

CD36 is a membrane protein involved in fatty acids uptake that is expressed in the endothelium, which has been associated with endothelial dysfunction in African Americans (AA). One in four AA is G-allele carriers for coding CD36 SNP rs3211938, which results in ~50% reduction in its expression. We reported that potentiating nitric oxide action (NO) with sildenafil restored endothelial dysfunction in conduit arteries in G-allele carriers. In this study, we tested the hypothesis that in G-allele carriers, sildenafil would improve insulin-induced microvascular recruitment (MBV) in response to fat infusion. We recruited 25 healthy AA (17 non-carriers [ages 34 ± 7.4] and eight G-allele carriers [42 ± 7.4 yrs]). Subjects underwent three visits: Visit 1: Saline infusion and hyperinsulinemic euglycemic clamp (HIE clamp). Visit 2: Lipid infusion and HIE clamp and Visit 3: Lipid infusion and HIE clamp after a four-week sildenafil treatment (60 mg/day). During each visit, the subjects underwent an assessment of MBV at baseline (bsl), after 3-hour insulin (Ins) infusion (40mu/m 2 /min) and after Ins and L-arginine (10mg/kg/min) for 30 min. infusion (Ins+L-arg). Ins+L-arg (saline day) increased the % change in MBV in both groups. However, this increase was less in carriers as compared to non-carriers (13.6±42.4 and 38.9±74.4), Fig. A. Intralipid (IL) infusion increased MBV but only in non-carriers, Fig. B . Treatment with sildenafil in the presence of IL infusion induced a decline in MBV in G-allele carriers Fig. C . In conclusion, healthy AAs with CD36 deficiency had a poor insulin-induced microvascular recruitment and appeared to be worsened by potentiating NO function with sildenafil.

Capsaicin-induced visceral deafferentation does not attenuate flavor conditioning by intragastric fat infusions in mice

The postoral actions of sugar and fat can rapidly stimulate the intake of and preference for flavors associated with these nutrients via a process known as appetition. Prior findings revealed that postoral glucose appetition is not attenuated following capsaicin-induced visceral deafferentation. The present experiment determined if capsaicin treatment altered fat appetition in C57BL/6 mice. Following capsaicin (Cap) or control (Con) treatment, mice were fitted with chronic intragastric (IG) catheters. They were then given 1-h sessions with a flavored saccharin solution (CS-) paired with IG water infusion or a different flavor (CS+) paired with IG 6.4% fat infusion. IG fat stimulated CS+ intakes in both Cap and Con mice, and the groups displayed similar preferences for CS+ over CS- in two-choice tests. These results confirm prior reports of normal fat conditioning in rats exposed to capsaicin or vagal deafferentation surgery. In contrast, other recent findings indicate that total or selective vagotomy alters the preference of mice for dilute vs. concentrated fat sources.

Evaluation of confirmatory data following the Article 12 MRL review for bentazone.

The applicant BASF SE submitted a request to the competent national authority in the Netherlands to evaluate the confirmatory data that were identified for bentazone in the framework of the maximum residue level (MRL) review under Article 12 of Regulation (EC) No 396/2005 as not available. To address the data gaps, a new livestock feeding study and storage stability data for bentazone and 6‐hydroxy bentazone in animal matrices were submitted. To address the data gap for potatoes, adjusted less critical good agricultural practices (GAPs) were reported and supporting residue data were provided. The data gap related to analytical methods in fat and herbal infusions were addressed in the framework of the peer review. The data gap for residue trials on leek has not been addressed. Further confirmation from the applicant/Member States are needed for the clarification of the GAP for herbal infusions. Based on the information submitted in support of the confirmatory data request, the existing EU MRLs for bentazone need to be modified for potato and leek, for swine fat and kidney and for bovine, equine, goat and sheep fat, liver and milk. The consumer risk assessment performed in the MRL review was updated, using new toxicological reference values derived by the peer review. No consumer intake concerns were identified.

Comparative effects of intraduodenal fat and glucose on the gut-incretin axis in healthy males

BackgroundThe interaction of nutrients with the small intestine stimulates the secretion of numerous enteroendocrine hormones that regulate postprandial metabolism. However, differences in gastrointestinal hormonal responses between the macronutrients are incompletely understood. In the present study, we compared blood glucose and plasma hormone concentrations in response to standardised intraduodenal (ID) fat and glucose infusions in healthy humans. MethodsIn a parallel study design, 16 healthy males who received an intraduodenal fat infusion were compared with 12 healthy males who received intraduodenal glucose, both at a rate of 2kcal/min over 120min. Venous blood was sampled at frequent intervals for measurements of blood glucose, and plasma total and active glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), insulin and glucagon. ResultsPlasma concentrations of the incretin hormones (both total and active GLP-1 and GIP) and glucagon were higher, and plasma insulin and blood glucose concentrations lower, during intraduodenal fat, when compared with intraduodenal glucose, infusion (treatment by time interaction: P<0.001 for each). ConclusionsCompared with glucose, intraduodenal fat elicits substantially greater GLP-1, GIP and glucagon secretion, with minimal effects on blood glucose or plasma insulin in healthy humans. These observations are consistent with the concept that fat is a more potent stimulus of the ‘gut-incretin’ axis than carbohydrate.

Effects of infusing milk precursors into the artery on rumen fermentation in lactating cows.

This experiment was conducted to investigate the effects of infusing milk precursors into the external pudic artery on rumen fermentation in lactating dairy cows. Eight multiparous Holstein cows were randomly assigned to Group A (experimental group) and Group B (control group) with 4 cows each. A 2 × 4 complex factor crossover design was used. Cows in Group A were fed corn straw as the only roughage, and cows in Group B were fed mixed roughage. The experiment was divided into two periods. In the first period, cows in Group A, received treatments: 1) a basal infusate as a control (CSC); 2) a milk fat precursor infusion including C16:0, C18:0, C18:1c9, C18:2c6, C18:3n3, acetic acid (CSF); 3) a milk protein precursor infusion including 16 amino acids (CSA); 4) the mixed infusion of milk fat and protein precursors (CSFA). And meanwhile, cows in Group B were infused the basal infusate as a control group. In the second period, the cows in both Groups A and B were crossed over, which cows in Group A were named as Group B and the cows originally in Group B were in Group A. The experimental results showed that cows in experimental group had higher ruminal pH compared with the control, and ruminal pH in CSC, CSF, CSA were significantly higher than those in their respective control group (P < 0.05). The concentration of ammonia nitrogen (NH3–N) was significantly higher in CSA and CSFA compared with Group B (P < 0.05). We also observed that the infusion of mixed amino acids significantly increased the bacterial protein (BCP) content in rumen (P < 0.05) and influenced the rumen acetic acid concentration as well as the acetic to propionic ratio (P < 0.05). Milk fat precursors infusion significantly affected butyric acid concentration (P < 0.05). In addition, the content of lipopolysaccharide (LPS) in CSA was significantly higher than that in the control group (P < 0.05). It is concluded that the milk precursors infused into external pudic artery caused feedback effects on ruminal fermentation under the corn straw roughage conditions. The milk protein precursor increased the ruminal pH, the contents of BCP and acetic acid, which adjust rumen fermentation and improve milk performance.

Amelioration of Metabolic Syndrome-Associated Cognitive Impairments in Mice via a Reduction in Dietary Fat Content or Infusion of Non-Diabetic Plasma

Obesity, metabolic syndrome (MetS) and type 2 diabetes (T2D) are associated with decreased cognitive function. While weight loss and T2D remission result in improvements in metabolism and vascular function, it is less clear if these benefits extend to cognitive performance. Here, we highlight the malleable nature of MetS-associated cognitive dysfunction using a mouse model of high fat diet (HFD)-induced MetS. While learning and memory was generally unaffected in mice with type 1 diabetes (T1D), multiple cognitive impairments were associated with MetS, including deficits in novel object recognition, cued fear memory, and spatial learning and memory. However, a brief reduction in dietary fat content in chronic HFD-fed mice led to a complete rescue of cognitive function. Cerebral blood volume (CBV), a measure of vascular perfusion, was decreased during MetS, was associated with long term memory, and recovered following the intervention. Finally, repeated infusion of plasma collected from age-matched, low fat diet-fed mice improved memory in HFD mice, and was associated with a distinct metabolic profile. Thus, the cognitive dysfunction accompanying MetS appears to be amenable to treatment, related to cerebrovascular function, and mitigated by systemic factors.