Differential Effects of Monounsaturated and Polyunsaturated Fats on Satiety and Gut Hormone Responses in Healthy Subjects

Functional and metabolic effects of omega-3 polyunsaturated fatty acid supplementation and the role of β-hydroxy-β-methylbutyrate addition in chronic obstructive pulmonary disease: A randomized clinical trial

INTRODUCTION

Short-term (4 weeks) supplementation with n-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) has recently been shown to improve protein metabolism in a dose dependent way in normal weight patients with Chronic Obstructive Pulmonary Disease (COPD). Furthermore, EPA/DHA supplementation was able to increase extremity lean soft tissue but not muscle function. No studies are available combining n-3 PUFAs and the leucine metabolite β-hydroxy-β-methylbutyrate (HMB) supplementation in chronic clinical conditions. Whether adding HMB to daily EPA/DHA supplementation for 10 weeks enhances muscle and brain health, daily functional performance, and quality of life of patients with COPD by further improving their protein and amino acid homeostasis remains unknown.

METHODS

Patients with COPD (GOLD: II-IV, n = 46) received daily for 10 weeks, according to a randomized double-blind placebo-controlled three-group design, EPA/DHA (n = 16), EPA/DHA to which HMB was added (n = 14), or placebo (n = 16). The daily dose of 2.0 g of EPA/DHA or soy + corn oil as the placebo was provided via gel capsules, and 3.0 g of Ca-HMB or maltodextrin as placebo as powders. At pre- and post-intervention, a pulse mixture of multiple amino acids was administered to measure postabsorptive net protein breakdown (netPB as primary endpoint) and whole body production (WBP) and conversion rates of the amino acids. As secondary endpoints, lean soft tissue and fat mass were assessed by dual-energy X-ray absorptiometry, upper and lower muscle function by handgrip and single leg isokinetic dynamometry, brain (cognitive, wellbeing) health by assessments, daily functional performance by measuring 6-min walk distance, 4-m gait speed, and postural balance, and quality of life by questionnaire. Plasma enrichments and concentrations were analyzed by LC-MS/MS, and systemic inflammatory profile and metabolic hormones by Luminex.

RESULTS

HMB + EPA/DHA but not EPA/DHA supplementation increased postabsorptive netPB (p = 0.028), and WBPs of glutamine (p = 0.024), taurine (p = 0.039), and tyrosine (p = 0.036). Both EPA/DHA and HMB + EPA/DHA supplementation resulted in increased WBP of phenylalanine (p < 0.05). EPA/DHA but not HMB + EPA/DHA was able to increase WBP of arginine (p = 0.030), citrulline (p = 0.008), valine (p = 0.038), and conversion of citrulline to arginine (p = 0.009). Whole body and extremity fat mass were reduced after HMB + EPA/DHA supplementation only, whereas lean soft tissue was increased after EPA/DHA (p = 0.049) and HMB + EPA/DHA (p = 0.073). No other significant findings were observed. Reductions in several proinflammatory cytokines were observed in the HMB + EPA/DHA group including IL-2, IL-17, IL-6, IL-12P40, and TNF-β (p < 0.05).

CONCLUSIONS

Ten weeks of supplementation with 2 g of EPA/DHA daily is sufficient to induce muscle gain in COPD but HMB is needed to induce fat loss. Whether HMB is solely responsible for the fat mass loss or has a synergistic effect with EPA/DHA remains unclear. The increase in net protein breakdown observed with HMB + EPA/DHA supplementation may indicate a beneficial enhanced protein turnover cycling associated with increased lean soft tissue.

CLINICAL TRIAL REGISTRY

ClinicalTrials.gov; NCT03796455.

Brain Perception of Different Oils on Appetite Regulation: An Anorectic Gene Expression Pattern in the Hypothalamus Dependent on the Vagus Nerve

(1) Background: We examined the effect of the acute administration of olive oil (EVOO), linseed oil (GLO), soybean oil (SO), and palm oil (PO) on gastric motility and appetite in rats. (2) Methods: We assessed food intake, gastric retention (GR), and gene expression in all groups. (3) Results: Both EVOO and GLO were found to enhance the rate of stomach retention, leading to a decrease in hunger. On the other hand, the reduction in food intake caused by SO was accompanied by delayed effects on stomach retention. PO caused an alteration in the mRNA expression of NPY, POMC, and CART. Although PO increased stomach retention after 180 min, it did not affect food intake. It was subsequently verified that the absence of an autonomic reaction did not nullify the influence of EVOO in reducing food consumption. Moreover, in the absence of parasympathetic responses, animals that received PO exhibited a significant decrease in food consumption, probably mediated by lower NPY expression. (4) Conclusions: This study discovered that different oils induce various effects on parameters related to food consumption. Specifically, EVOO reduces food consumption primarily through its impact on the gastrointestinal tract, making it a recommended adjunct for weight loss. Conversely, the intake of PO limits food consumption in the absence of an autonomic reaction, but it is not advised due to its contribution to the development of cardiometabolic disorders.

Annatto-Enriched Egg Improves the Perception of Satiety in Healthy Adults-Randomized Clinical Trial: EGGANT Study

Diet is one of the factors that prevents the development and death from cardiovascular diseases (CVD). It has been proposed that diets high in protein, which increase satiety, and with a high content of antioxidants, help reduce cardiovascular risk factors. The egg is one of the foods that produces greater satiety and provides antioxidants. In addition, due to its lipophilic matrix, it could improve the bioavailability of other dietary antioxidants such as Annatto.

OBJECTIVE

This study evaluated the effects of egg and annatto-enriched egg consumption on satiety markers and CVD risk factors in healthy adults from Colombia.

METHODS

A parallel randomized clinical trial was conducted, where one hundred and five (n = 105) men and women, divided into three groups, consumed daily for 8 weeks: (a) two eggs (egg group), or (b) two eggs with annatto (egg + annatto group), or (c) two egg whites (placebo group).

RESULTS

The three groups were similar in gender distribution. No significant changes were found over time (before vs. after) in any of the groups nor between the groups in anthropometric variables, physical activity, eating profile, and ghrelin as an objective marker of satiety. In the egg + annatto group, subjective satiety increased (effect size 0.431; p < 0.05) after consumption.

CONCLUSIONS

In healthy adults, the intake of two eggs, or two eggs with annatto daily for 8 weeks, did not result in significant changes in ghrelin; but eggs with annatto tend to increase the perception of satiety.

Effects of n-3 polyunsaturated fatty acid supplementation on appetite: a systematic review and meta-analysis of controlled clinical trials

BACKGROUND

The current studies explore the effect of omega-3 polyunsaturated fatty acids (PUFAs) on appetite.

OBJECTIVE

To examine the effect of omega-3 polyunsaturated fatty acids (n-3 PUFAs) on appetite using a systematic review and meta-analysis of controlled clinical trials (CTs).

PATIENTS AND METHODS

Online databases including PubMed, Scopus, ISI Web of Science, and Google Scholar were searched up to January 2022. A random-effects model was used to compare the overall standardized mean difference in appetite scores between n-3 PUFAs supplemented and control individuals.

RESULTS

Fifteen eligible CTs with 1504 participants (872 for n-3 PUFA supplementation and 632 for placebo groups) were included in our systematic review. The meta-analysis showed no significant difference in overall appetite score between n-3 PUFAs supplemented and control groups (standardized mean difference [SMD] = 0.458, 95% confidence interval [CI] - 0.327, 1.242, P value = 0.25). However, the n-3 PUFA supplementation significantly increased the desire to eat (SMD = 1.07, 95% CI 0.116, 2.029, P = 0.02) compared to control.

CONCLUSION

Although we found no effect of omega-3 supplementation on overall appetite score, it modestly increases the desire to eat. Further CTs evaluating the effect of PUFAs on appetite are still needed to confirm these findings.

Nut-enriched energy restricted diet has potential to decrease hunger in women at cardiometabolic risk: a randomized controlled trial (Brazilian Nuts Study)

Successful weight management represents a challenge to obesity control. Evidence suggests that nut consumption promotes a prolonged satiety response. Therefore, we hypothesize that nuts could be associated with greater weight loss in comparison to a control group, and we evaluate the acute and long-term effects of Brazilian nuts (BN: 15 g of Brazil nuts + 30 g of cashew nuts) included in an energy-restricted intervention on food intake, appetite, and peptide hormones. We conducted an 8-week, randomized, open-label, controlled, parallel-arm clinical trial with 28 women at cardiometabolic risk who received an energy-restricted diet containing BN or an energy-restricted nut-free diet (control). At baseline and after 8 weeks of intervention, subjective postprandial appetite ratings were assessed using a visual analog scale (VAS) before and after consumption (0, 10, 60, 120, 180, and 240 minutes) of a 437-kcal nut-enriched (BN group) or nut-free (control) breakfast meal. Subsequently, an ad libitum lunch was served, and the participants completed another VAS at 280 minutes. Plasma concentrations of ghrelin, glucose-dependent insulinotropic polypeptide, glucagon-like peptide 1, and leptin were measured at fasting and postprandially at 60, 120, and 240 minutes. Last, subsequent reported 24-hour energy intake was assessed in a free-living setting. BN consumption did not have acute effects on food intake, appetite, or peptide hormones. However, after an 8-week intervention, postprandial ghrelin (difference between post- and preintervention area under the curve) decreased in the BN group in comparison to the control (mean difference, 1978 pg/mL/min, 95% CI, 27-3929 pg/mL/min; P = .047) and therefore, an energy-restricted diet containing demonstrated potential to decrease hunger in cardiometabolic risk women.

Fat Intake and High Triglyceride-Glucose Index in Individuals at Cardiometabolic Risk: An Isocaloric Substitution Analyses

Insulin resistance (IR) is an important risk factor for cardiovascular diseases, and the triglyceride-glucose index (TyG index) is a potential IR biomarker. Evidence also suggests that fat intake may modulate IR status, but this relationship remains unclear. Thus, the present study aimed to analyze the relationship between the TyG index and isocaloric replacement of macronutrients, including the profile of dietary fatty acids in individuals at cardiometabolic risk.

This cross-sectional study enrolled 264 individuals at cardiometabolic risk (age 43.1 ± 16.3 years) who participated in a nutritional intervention study (ReBEC, id: RBR-5n4y2g). The baseline demographic, anthropometric, clinical, dietary, and lifestyle data were used. The TyG index was calculated using the formula ln [fasting triglycerides (mg/dL) × fasting plasma glucose (mg/dL)/2]. Multivariate nutrient density models were used to analyze isocaloric replacement of fatty acids (as 5% of energy). The chance of having a high TyG index (TyG index >8.83, median value) was decreased by 60% after replacing 5% of the energy intake of polyunsaturated fatty acid (PUFA), saturated fatty acid (SFA), and trans fatty acid (TFA) with monounsaturated fatty acid (MUFA) or PUFA and SFA with protein.

Isocaloric replacement of PUFA, SFA, and TFA with MUFA and protein was associated with lower chances of having a high TyG index. These results indicate the importance of macronutrient and dietary fat profiles in the dietary planning of individuals at cardiometabolic risk.

An Isolated Dose of Extra-Virgin Olive Oil Produces a Better Postprandial Gut Hormone Response, Lipidic, and Anti-Inflammatory Profile that Sunflower Oil: Effect of Morbid Obesity

INTRODUCTION

This study evaluates the effects of 25 mL of three types of oils [extra-virgin olive oil (EVOO), olive oil (OO), and sunflower oil (SO)] on postprandial (3 h) satiety markers and variables related to metabolic status and inflammation in non-obese patients (n = 6) and in those with morbid obesity (n = 6), before and 1 year after Roux-en-Y gastric by-pass (RYGB).

METHODS AND RESULTS

After EVOO intake, serum acylated ghrelin decreases and GLP1 increases more than with OO and SO. EVOO causes a higher increase of insulin and lower postprandial hypertriglyceridemia and free fatty acid levels than with OO and SO. EVOO decreases TNFα and IL6 expression in peripheral blood mononuclear cells, with OO inducing intermediate effects and SO inducing an increase of these proinflammatory markers. These results are observed in non-obese patients and in those with morbid obesity after RYGB. However, patients with morbid obesity before RYGB show a profound alteration of this response.

CONCLUSION

EVOO produces more beneficial effects than OO, which has lower amounts of minor components, and SO, which has PUFA as its main component. RYGB produces an improvement in the metabolic response to all three types of oils in patients with morbid obesity.

Effect of Gazpacho, Hummus and Ajoblanco on Satiety and Appetite in Adult Humans: A Randomised Crossover Study

Nowadays, overweight and obesity has reached an epidemic level around the world. With the aim to tackle them, an interesting strategy is the study of food and ingredients with satiety properties. In addition to reducing food and/or calorie intake, this type of foods must be included as part of a healthy diet. With regard to this, it is well known that the Mediterranean Diet (MD) is a feeding pattern that helps us to maintain good health, providing an adequate intake of micronutrients and active compounds. With this background, the main aim of this research was to identify MD foods with a high satiating potential capacity. For this purpose, three typical foods of the Mediterranean region, mainly based on vegetables, were selected: hummus, ajoblanco and gazpacho. As a control, white bread was used. Twenty-four human healthy volunteers consumed a standard breakfast followed by the different typical Mediterranean foods, and then the subjective sensation of hunger and satiety for each food was assessed by visual analogue scales (VAS) during 3 h. Subsequently, volunteers had ad libitum access to a standard meal. The results indicate that gazpacho showed the highest satiating scores, despite the fact that it was not the food that provided the highest protein or fibre amount. More studies of this type are needed to determine the proportion and/or combination of ingredients from these classical Mediterranean recipes that could enhance human satiety.

Selective release of gastrointestinal hormones induced by an orally active GPR39 agonist

OBJECTIVES

Obesity is a complex disease associated with a high risk of comorbidities. Gastric bypass surgery, an invasive procedure with low patient eligibility, is currently the most effective intervention that achieves sustained weight loss. This beneficial effect is attributed to alterations in gut hormone signaling. An attractive alternative is to pharmacologically mimic the effects of bariatric surgery by targeting several gut hormonal axes. The G protein-coupled receptor 39 (GPR39) expressed in the gastrointestinal tract has been shown to mediate ghrelin signaling and control appetite, food intake, and energy homeostasis, but the broader effect on gut hormones is largely unknown. A potent and efficacious GPR39 agonist (Cpd1324) was recently discovered, but the in vivo function was not addressed. Herein we studied the efficacy of the GPR39 agonist, Cpd1324, on metabolism and gut hormone secretion.

METHODS

Body weight, food intake, and energy expenditure in GPR39 agonist-treated mice and GPR39 KO mice were studied in calorimetric cages. Plasma ghrelin, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and peptide YY (PYY) levels were measured. Organoids generated from murine and human small intestine and mouse colon were used to study GLP-1 and PYY release. Upon GPR39 agonist administration, dynamic changes in intracellular GLP-1 content were studied via immunostaining and changes in ion transport across colonic mucosa were monitored in Ussing chambers. The G protein activation underlying GPR39-mediated selective release of gut hormones was studied using bioluminescence resonance energy transfer biosensors.

RESULTS

The GPR39 KO mice displayed a significantly increased food intake without corresponding increases in respiratory exchange ratios or energy expenditure. Oral administration of a GPR39 agonist induced an acute decrease in food intake and subsequent weight loss in high-fat diet (HFD)-fed mice without affecting their energy expenditure. The tool compound, Cpd1324, increased GLP-1 secretion in the mice as well as in mouse and human intestinal organoids, but not in GPR39 KO mouse organoids. In contrast, the GPR39 agonist had no effect on PYY or GIP secretion. Transepithelial ion transport was acutely affected by GPR39 agonism in a GLP-1- and calcitonin gene-related peptide (CGRP)-dependent manner. Analysis of Cpd1324 signaling properties showed activation of Gα_q and Gα_i/o signaling pathways in L cells, but not Gα_s signaling.

CONCLUSIONS

The GPR39 agonist described in this study can potentially be used by oral administration as a weight-lowering agent due to its stimulatory effect on GLP-1 secretion, which is most likely mediated through a unique activation of Gα subunits. Thus, GPR39 agonism may represent a novel approach to effectively treat obesity through selective modulation of gastrointestinal hormonal axes.

Manipulation of fatty acid composition in a high-fat meal does not result in differential alterations in appetite or food intake in normal weight females: A single-blind randomized crossover study

A behavioral concept that generates a path to obesity is eating in the absence of hunger (EAH). One strategy that may be effective in preventing EAH is the manipulation of dietary fatty acid (FA) composition. However, it remains unclear which FA has the greatest impact on both appetite and EAH. Therefore, the purpose of this study was to examine the effect of different dietary FA compositions (monounsaturated, MUFA; polyunsaturated, PUFA; saturated, SFA) on subjective ratings of appetite and subsequent ad libitum eating after a 3 h postprandial period. Sixteen apparently healthy normal weight females between ages 18-40 completed this randomized, single-blind, crossover study. Participants consumed a HF meal (65% energy from fat) rich in SFA, MUFA, and PUFA with an energy content corresponding to 35% of their measured resting metabolic rate on three separate occasions. Visual analog scales were collected while fasted and every 30 min for 3 h during a postprandial period to measure feelings of hunger, fullness, and desire to eat (DTE). Participants were provided an ad libitum buffet meal 3 h after the HF meal. There were no statistically significant differences for ratings of hunger, fullness, or DTE across conditions. Further, there was no significant difference in energy intake during the ad libitum lunch. We conclude that the manipulation of FA composition in a HF meal does not differentially affect appetite sensations or subsequent energy intake.