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Mitochondrial dysfunction occurs in monocytes during obesity and contributes to a low-grade inflammatory state; therefore, maintaining good mitochondrial conditions is a key aspect of maintaining health. Dietary interventions are primary strategies for treating obesity, but little is known about their impact on monocyte bioenergetics. Thus, the aim of this study was to evaluate the effects of calorie restriction (CR), intermittent fasting (IF), a ketogenic diet (KD), and an ad libitum habitual diet (AL) on mitochondrial function in monocytes and its modulation by the gut microbiota. A randomized controlled clinical trial was conducted in which individuals with obesity were assigned to one of the 4 groups for 1 month. Subsequently, the subjects received rifaximin and continued with the assigned diet for another month. The oxygen consumption rate (OCR) was evaluated in isolated monocytes, as was the gut microbiota composition in feces and anthropometric and biochemical parameters. Forty-four subjects completed the study, and those who underwent CR, IF and KD interventions had an increase in the maximal respiration OCR (p = 0.025, n2p = 0.159 [0.05, 0.27] 95% confidence interval) in monocytes compared to that in the AL group. The improvement in mitochondrial function was associated with a decrease in monocyte dependence on glycolysis after the IF and KD interventions. Together, diet and rifaximin increased the gut microbiota diversity in the IF and KD groups (p = 0.0001), enriched the abundance of Phascolarctobacterium faecium (p = 0.019) in the CR group and Ruminococcus bromii (p = 0.020) in the CR and KD groups, and reduced the abundance of lipopolysaccharide (LPS)-producing bacteria after CR, IF and KD interventions compared to the AL group at the end of the study according to ANCOVA with covariate adjustment. Spearman's correlation between the variables measured highlighted LPS as a potential modulator of the observed effects. In line with this findings, serum LPS and intracellular signaling in monocytes decreased with the three interventions (CR, p = 0.002; IF, p = 0.001; and KD, p = 0.001) compared to those in the AL group at the end of the study. We conclude that these dietary interventions positively regulate mitochondrial bioenergetic health and improve the metabolic profile of monocytes in individuals with obesity via modulation of the gut microbiota. Moreover, the evaluation of mitochondrial function in monocytes could be used as an indicator of metabolic and inflammatory status, with potential applications in future clinical trials. This trial was registered with ClinicalTrials.gov (NCT05200468). [Display omitted] [ABSTRACT FROM AUTHOR]

Background and Aim: Circulating amino acids are modified by sex, body mass index (BMI) and insulin resistance (IR). However, whether the presence of genetic variants in branched-chain amino acid (BCAA) catabolic enzymes modifies circulating amino acids is still unknown. Thus, we determined the frequency of two genetic variants, one in the branched-chain aminotransferase 2 (BCAT2) gene (rs11548193), and one in the branched-chain ketoacid dehydrogenase (BCKDH) gene (rs45500792), and elucidated their impact on circulating amino acid levels together with clinical, anthropometric and biochemical parameters.Methods and Results: We performed a cross-sectional comparative study in which we recruited 1612 young adults (749 women and 863 men) aged 19.7 ± 2.1 years and with a BMI of 24.9 ± 4.7 kg/m2. Participants underwent clinical evaluation and provided blood samples for DNA extraction and biochemical analysis. The single nucleotide polymorphisms (SNPs) were determined by allelic discrimination using real-time polymerase chain reaction (PCR). The frequencies of the less common alleles were 15.2 % for BCAT2 and 9.83 % for BCKDH. The subjects with either the BCAT2 or BCKDH SNPs displayed no differences in the evaluated parameters compared with subjects homozygotes for the most common allele at each SNP. However, subjects with both SNPs had higher body weight, BMI, blood pressure, glucose, and circulating levels of aspartate, isoleucine, methionine, and proline than the subjects homozygotes for the most common allele (P < 0.05, One-way ANOVA).Conclusion: Our findings suggest that the joint presence of both the BCAT2 rs11548193 and BCKDH rs45500792 SNPs induces metabolic alterations that are not observed in subjects without either SNP. [ABSTRACT FROM AUTHOR]

The amino acid profile of young adults is modified by sex, body mass index (BMI) and insulin resistance (IR). However, we do not know if age or the presence of specific polymorphisms in the genes of BCAT2 and BCKDH contribute to changes in the amino acid profile, especially in subjects with obesity. Therefore, we have evaluated the effect of age, the presence of IR and the polymorphisms of BCAT2 rs11548193 and BCKDH rs45500792 on the concentration of amino acids in subjects with obesity. This was a cross-sectional study conducted with 487 subjects with obesity. Participants underwent a physical examination in which their clinical history was obtained and a blood sample was taken for biochemical, hormonal, and DNA analysis. Adults <30 years old with obesity had higher levels of alanine, arginine, aspartate, histidine, leucine, lysine, methionine, phenylalanine, proline, serine and valine than adults ≥30 years old. Interestingly, regardless of age, we found that arginine, aspartate, serine decreased, while proline and tyrosine increased in the presence of IR; tyrosine and sum of branched-chain amino acids (∑BCAA) were the amino acids that increased in the presence of BCAT2 rs11548193 and BCKDH rs45500792 polymorphisms. We found that the amino acid profiles of subjects with obesity are differentially modified by age, the presence of IR, and the presence of the BCAT2 rs11548193 and BCKDH rs45500792 polymorphisms. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases (CVDs) are the leading cause of global death. Hypercholesterolemia is among the main risk factors for developing cardiovascular events, and is highly prevalent in the Mexican population. The primary objective of the present work was to assess the effect of a dietary portfolio (DP) with functional foods containing dehydrated nopal, soy protein, chia seeds, inulin, and oats in LDL-C and TC concentrations of subjects with mild hypercholesterolemia. Also, we explored the changes in the profile of the lipoprotein subclasses measured by nuclear magnetic resonance spectroscopy (NMR). Sixty-two subjects (47 women, 15 men) with mild hypercholesterolemia (LDL-C, ≥130 ≤ 190 mg/dL, TC > 200 mg/dL) completed the randomized, parallel, controlled study. The dietary intervention was given in two stages. First, a dietary standardization stage with a low saturated fat diet (LSFD) which matched the habitual energy intake of the volunteers for 2-weeks, followed by 2.5 months of dietary intervention with a LSFD plus placebo (PL) or DP. Subjects who consumed the LSFD + DP interventions had a significantly higher reduction of LDL-C (−18.05%, P = 0.003) and TC (−17.08%, P = 0.02) compared to volunteers who consumed an LSFD for the same period. Furthermore, the lipoprotein subclass profiling showed that the small low-density-lipoproteins, and the small high-density-lipoproteins significantly decreased (P = 0.04, P < 0.001, respectively), conveying a less atherogenic state. At the end of the study, 78% of the subjects who consumed LSFD + DP reduced their LDL-C below 160 mg/dL, and of these, 47% reduced it below 130 mg/dL. Based on the results obtained from this study, the inclusion of functional foods as part of the lifestyle modifications is recommended to treat mild hypercholesterolemia and reduce cardiovascular risk. Registered under ClinicalTrials.gov Identifier no. NCT04148976. [ABSTRACT FROM AUTHOR]

Background: Chronic low‐grade inflammation is one of the main drivers of cognitive decline. The MIND Diet is a dietary pattern that includes foods rich in antioxidants that exert a neuroprotective effect by decreasing oxidative stress (OS) and inflammation. The aim was to evaluate the association between inflammation markers and the intake of foods characteristic of the MIND diet with body composition in older adults. Method: Cross‐sectional analysis of 73 older adults (70.6±4.6 years, 63% women) without cognitive decline who are participating in the LatAm Fingers study in Mexico. Basal blood samples were taken to determine C‐reactive protein (CRP) and Lipopolysaccharide (LPS). Subjects were divided into two groups according to CRP levels (≤1.0 mg/L without inflammation; >1.0 mg/L with inflammation). Body composition was measured by multi‐frequency bioelectrical impedance (Inbody 720). Participants were asked to autocomplete a validated food frequency questionnaire (POINTER) to evaluate the dietary intake of the MIND diet foods (leafy green vegetables, other vegetables, olive oil, fish, poultry, nuts, whole grains, legumes, and berries). Low adherence was defined as a total score of <8 out of 15 points. Result: 74% of women presented elevated CRP levels (>1.0mg/L). Interestingly, subjects from the group without inflammation had lower values of body mass index (BMI) (27.2 ± 2.4 vs. 30.0 ± 3.6 Kg/m²; p = 0.002), total fat percentage (35.5 ± 5.6 vs. 42.9 ± 6.9%; p = 0.0001) and visceral fat area (108.3 ± 20.7 vs. 123.6 ± 24.0 cm²; p = 0.012) and higher levels of total muscle mass (23.9 ± 5.0 vs. 21.6 ± 4.3Kg; p = 0.049). All participants had metabolic endotoxemia (LPS levels 450 ± 211 ng/mL). Compliance with the MIND diet was deficient (score <8 points) in most participants (58.3%). Conclusion: High levels of CRP are associated with a negative impact on body composition in older Mexican adults. Additionally, this population is at high risk of cognitive decline as it presents elevated markers of systemic inflammation with a low intake of neuroprotective foods. [ABSTRACT FROM AUTHOR]

Summary Background & aims Accurate predictive equations of resting energy expenditure (REE) are crucial in devising nutritional strategies to manage overweight/obesity, especially in countries where these are highly prevalent. REE is the most common measurement used to estimate energy requirements in the nutritional context; the most accurate method of measuring REE is indirect calorimetry (IC). However, this method is costly and often rarely feasible in many clinical settings. The objective of the present study was to develop and validate a new equation for predicting REE in adults with overweight and obesity. Methods This was a cross-sectional study including 410 men and women with overweight and obesity (20–60 y). Participants were randomly assigned; the development group included 200 subjects and the validation group 210 subjects. The new predictive equation was derived using stepwise multiple linear regression analysis. The accuracy of the new equation was compared to several existing predictive equations (PEs). The accuracy rate was calculated as the percentage of subjects whose REE-PE was within ±10% of the REE-IC. REE was measured by IC and anthropometric measurements. Results One predictive equation was developed (NEQ) in which weight was the strongest predictor of REE. Compared with others predicted equations already using, the new designed equation showed the less mean bias (Kj/day): NEQ: 25.7, Valencia:129, WHO/FAO/United Nations University: 270, Mifflin-St Jeor: 308, Owen: −808, Carrasco: −1097, Korth: −36.4, Johnstone: −375, Livingstone: −315, De Lorenzo: −28.3, Lazzer: −123, Muller: −145, Huang: −399 and Bernstein: −1335. Conclusions The present equation had the highest predictive accuracy in subjects with overweight or obesity compared with the previous equations derived from different populations. Thus, these new equation can be used to assist the nutritional management of these subjects. [ABSTRACT FROM AUTHOR]

The purpose of this study was to characterize the in vitro specific reactive oxygen species (ROS) scavenging activity of nopal extracts and to study the effect of nopal consumption on plasma antioxidant capacity. The in vitro hydrolysis of the extract increased its antioxidant activity and the concentration of total polyphenols. The hydrolyzed extract showed ability to scavenge hydroxyl radical, hydrogen peroxide, peroxynitrite anion, superoxide anion and hypochlorous acid. Quercetin, isorhamnetin and kaempferol were identified in this extract by high-performance liquid chromatography (HPLC)/mass spectrometry and vitamin C by HPLC. The antioxidant activity of nopal was compared with that of different foods and the following order was found: coffee > garlic > nopal > plum > chia seeds. Nopal consumption increased blood and plasma antioxidant activity in healthy subjects. Thus, nopal showed in vitro and in vivo antioxidant activity that may be, at least in part, due to the presence of polyphenols and vitamin C. [ABSTRACT FROM AUTHOR]

Abstract: During lactation, the mammary gland increases the needs for nutrients to fulfill the milk production requirements. Among these nutrients, amino acids play an important role for the synthesis of milk proteins. Amino acids are supplied to the mammary gland through amino acid transporters, although some are synthesized in situ. The purpose of this study was to establish the pattern of changes in messenger RNA abundance of the amino acid transporters ASC, system L, EAAC1, GLAST, CAT-1, and Tau in the mammary gland of the rat during different stages of pregnancy and lactation. Rats were fed during pregnancy and lactation a 20% casein diet. Food intake increased significantly during the lactation period. Amino acid transporter ASC expression increased during the first days of pregnancy about 2-fold, and it was increased in a lesser extent again during the peak of lactation. The expression of system L (LAT-1) and CAT-1 transporters was increased only during the lactation period. On the other hand, the expression of the transporters for anionic amino acids EAAC1 and GLAST was low during both stages. Finally, taurine transporter expression decreased during pregnancy; and it was significantly lower during lactation. These results showed that amino acid transporters were not expressed similarly in the mammary gland during pregnancy and lactation, indicating that the expression of these transporters did not respond only to the metabolic needs of the gland but depended on the dietary protein supply and possibly the specific hormonal changes that occur during pregnancy and lactation. [Copyright &y& Elsevier]

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The preservation of body proteins is essential to guarantee their functions in organisms. Therefore, the utilization of amino acids as energy substrates is regulated by a precise fine-tuned mechanism. Recent evidence suggests that the transcription factors peroxisome proliferator-activated receptor alpha (PPARα) and hepatocyte nuclear factor 4 alpha (HNF4α) are involved in this regulatory mechanism. Thus, the aim of this study was to determine how these transcription factors interact to regulate the expression of amino acid catabolism genes. In vivo studies using PPARα-knockout mice (Pparα-null) fed different amounts of dietary protein showed that in the absence of PPARα, there was a significant increase in HNF4α abundance in the liver, which corresponded with an increase in amino acid catabolizing enzyme (AACE) expression and the generation of increased amounts of postprandial urea. Moreover, this effect was proportional to the increase in dietary protein consumed. Chromatin immunoprecipitation assays showed that HNF4α can bind to the promoter of AACE serine dehydratase (SDS), an effect that was potentiated by dietary protein in the Pparα-null mice. The mechanistic studies revealed that the presence of retinoid X receptor alpha (RXRα) is essential to repress HNF4α activity in the presence of PPARα, and this interaction accelerates HNF4α degradation via the proteasome pathway. These results showed that PPARα can downregulate liver amino acid catabolism in the presence of RXRα by inhibiting HNF4α activity. Unlabelled Image • PPARα deletion increases HNF4α and the expression of amino acid catabolism genes in the liver. • Increase in dietary protein intake and PPARα deletion promotes HNF4α binding to the Sds promoter. • Upon activation, PPARα interacts with HNF4α and this interaction requires the presence of RXRα. • PPARα and RXRα repress HNF4α transcriptional activity by inducing its proteasomal degradation. [ABSTRACT FROM AUTHOR]

Angiotensin-(1-7) [Ang-(1-7)], a component of the renin angiotensin system, is a vasodilator that exerts its effects primarily through the Mas receptor. The discovery of the Mas receptor in white adipose tissue (WAT) suggests an additional role for this peptide. The aim of the present study was to assess whether Ang-(1-7) can induce the expression of thermogenic genes in white adipose tissue and increase mitochondrial respiration in adipocytes. Stromal Vascular fraction (SVF)-derived from mice adipose tissue was stimulated for one week with Ang-(1-7), then expression of beige markers and mitochondrial respiration were assessed. Mas+/+ and Mas−/− mice fed a control diet or a high fat-sucrose diet (HFSD) were exposed to a short or long term infusion of Ang-(1-7) and body weight, body fat, energy expenditure, cold resistance and expression of beige markers were assessed. Also, transgenic rats overexpressing Ang-(1-7) were fed with a control diet or a high fat-sucrose diet and the same parameters were assessed. Ang-(1-7) circulating levels from human subjects with different body mass index (BMI) or age were measured. Incubation of adipocytes derived from SVF with Ang-(1-7) increased the expression of beige markers. Infusion of Ang-(1-7) into lean and obese Mas+/+mice also induced the expression of Ucp1 and some beige markers, an effect not observed in Mas−/− mice. Mas−/− mice had increased body weight gain and decreased cold resistance, whereas rats overexpressing Ang-(1-7) showed the opposite effects. Overexpressing rats exposed to cold developed new thermogenic WAT in the anterior interscapular area. Finally, in human subjects the higher the BMI, low circulating concentration of Ang-(1-7) levels were detected. Similarly, the circulating levels of Ang-(1-7) peptide were reduced with age. These data indicate that Ang-(1-7) stimulates beige markers and thermogenesis via the Mas receptor, and this evidence suggests a potential therapeutic use to induce thermogenesis of WAT, particularly in obese subjects that have reduced circulating concentration of Ang-(1-7). Unlabelled Image • Ang-(1-7) induces the expression of beige markers in white adipose tissue. • Ang-(1-7) stimulates energy expenditure and increases mitochondrial respiration. • Thermogenesis is activated by Ang-(1-7) via Mas receptor. • Overexpression of Ang-(1-7) induces resistance to obesity. • Obese humans show low levels of circulating Ang-(1-7). [ABSTRACT FROM AUTHOR]