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Low Carbohydrate Availability in Energy Balance Alters Bone Turnover and Muscle Proteomic Response With Limited Endocrine Disruption.

Training with low carbohydrate availability (LCA) has been proposed as an independent determinant of physiological perturbations commonly attributed to low energy availability (LEA) and to increase skeletal muscle oxidative machinery, yet the effects of LCA in isolation from LEA remain unclear. We examined whether short-term carbohydrate restriction under energy balance alters endocrine and metabolic markers associated with LEA and skeletal muscle proteomic response. In a randomized crossover design, eight trained males completed 4 days of either a low-carbohydrate high-fat diet (LOW; 12% carbohydrate, 69% fat, 19% protein) or a normal-carbohydrate diet (NORM; 62% carbohydrate, 19% fat, 19% protein), while undertaking daily cycloergometer exercise (15 kcal kg FFM-1 day-1) and maintaining energy availability at 45 kcal kg FFM-1 day-1. LOW induced a clear metabolic shift consistent with LCA, evidenced by elevated circulating free fatty acids, glycerol and β-hydroxybutyrate, in fasting conditions and fat oxidation at rest and during exercise, alongside reduced exercise glucose concentrations. Despite these responses, LOW did not alter insulin, testosterone, triiodothyronine, leptin, hepcidin, or P1NP. In contrast, β-CTX increased and IGF-1 decreased relative to NORM. Muscle glycogen concentration decreased only in LOW (40% ± 14%). Proteomic analysis identified 671 proteins; 57 differentially expressed in LOW relative to NORM were limited to fatty acid metabolism pathways and suppression of ribosomal, sarcomeric, and extracellular matrix proteins. These findings indicate that isolated LCA exerts limited endocrine disruption but may selectively compromise bone turnover and muscle anabolic response, suggesting that without acute LEA, LCA has limited influence on muscle oxidative phenotype.

Male

Skeletal Muscles Do Not Compete for Growth: Activating Additional Muscle Mass Does Not Compromise Changes in Muscle Size.

Kataoka, R, Yamada, Y, Hammert, WB, Sallberg, RW, Kang, A, Song, JS, Kassiano, W, Metcalf, EE, and Loenneke, JP. Skeletal muscles do not compete for growth: Activating additional muscle mass does not compromise changes in muscle size. J Strength Cond Res 40(9): 1043-1049, 2026-This study investigated whether the magnitude of muscle size and strength differed based on the amount of muscle recruited during training sessions. One hundred five untrained individuals were randomly assigned to 1 of 3 groups: low-load unilateral elbow flexion exercise (a) to failure (LL-Failure, n = 36), (b) to failure and low-load knee extension exercise to failure (LL-Failure + Legs, n = 33), or (c) a time-matched nonexercise control (CON, n = 36). Training groups completed 18 supervised sessions over 6 weeks (2 sets at 30% 1 repetition maximum [1RM] to failure). LL-Failure + Legs group performed 4 additional sets of knee extension exercise in each leg (20-30 RM). Muscle thickness on the anterior upper arm (60 and 70% sites) and elbow flexor 1RM strength of the trained arm were measured at pretesting and posttesting. Changes were compared using the ANCOVA function of Bayes Factors for Informative Hypotheses (prevalues as the covariate). Specific hypotheses were evaluated by comparing Bayes factors and the posterior probabilities between models. Six weeks of training led to increases in muscle size and strength. However, performing additional leg exercise did not attenuate the muscle growth in the anterior upper arm (0.19 cm) compared with performing only arm exercise to failure (0.18 cm). Changes in 1RM strength also did not differ between training groups (0.32 and 0.25 kg for LL-Failure and LL-Failure + Legs, respectively). Overall, there was no evidence for competition of adaptations in muscle size and strength under uncontrolled nutritional conditions. Whether greater training volume or limited nutrient intake induces a competition for resources warrants further investigation.

Humans

Increasing gut short-chain fatty acids protects intestinal barrier function but does not spare muscle glycogen or impact aerobic performance.

Animal studies suggest gut microbiota-derived short-chain fatty acids (SCFA) provide an intestinal barrier-protecting, glycogen-sparing energy source that increases aerobic endurance performance, but confirmation in humans is needed. This study aimed to determine whether increasing colonic SCFA availability impacts intestinal barrier function, substrate metabolism, muscle glycogen and aerobic performance in healthy adults. Using a randomized, double-blind, crossover design 12 active men (age 18-30&#xa0;years;40.0&#xa0;&#xb1;&#xa0;7.1&#xa0;mL/kg/min) performed prescribed exercise and consumed a provided diet supplemented with acetylated and butyrylated high-amylose maize starch engineered to deliver SCFA to the colon (HAMS-A/B) or low-amylose maize starch (LAMS) for 7 days, separated by a 2 week washout. Indirect calorimetry, stable isotopes and blood, muscle and urine biomarkers were measured on intervention day 8 while participants completed 90&#xa0;min of steady-state cycle ergometry (ExSS; 60 &#xb1; 5%) followed by a 5&#xa0;km treadmill time trial. HAMS-A/B, relative to LAMS, increased faecal and serum SCFA. Multiple markers of intestinal barrier damage and permeability were lower, and the respiratory exchange ratio during ExSS was higher (0.02 [95% confidence interval (CI): 0.01, 0.03], Ptreatment&#xa0;<&#xa0;0.001) following HAMS-A/B versus LAMS. However no between-treatment difference in glucose turnover, muscle glycogen depletion (14&#xa0;&#xb5;mol/kg/g dry wt. [95% CI: -116, 143], Pinteractio n&#xa0;=&#xa0;0.613) or TT performance (5&#xa0;s [95%CI: -44, 54], Ptreatment&#xa0;=&#xa0;0.816) was observed. Increasing colonic and circulating SCFA modestly altered substrate oxidation and preserved intestinal barrier function during endurance exercise. However effects were not sufficient to spare muscle glycogen or increase aerobic endurance performance, leaving the practical relevance unclear and underscoring challenges inherent in translating promising preclinical findings to humans. KEY POINTS: Animal studies suggest gut microbiota-derived short-chain fatty acids (SCFA) provide an intestinal barrier-protecting, glycogen-sparing energy source that increases aerobic endurance performance, but confirmation in humans is lacking. A gut microbiota-targeted dietary supplementation strategy was used to deliver SCFA to the colon and successfully increased colonic and systemic SCFA concentrations in healthy, physically active adults before and during an endurance exercise bout and aerobic performance test. Increasing colonic and systemic SCFA availability preserved intestinal barrier function but did not impact glucose turnover, alter protein expression in muscle or spare muscle glycogen during endurance exercise. Increasing colonic and systemic SCFA availability did not impact aerobic endurance performance.

Humans

Acute and chronic effects of mixed nuts on energy metabolism in women at cardiometabolic risk: a randomized clinical trial.

BACKGROUND AND AIMS: The effect of consuming a mix of Brazilian nuts on energy metabolism has not been explored. Thus, the present study aimed to evaluate the effects of acute and chronic consumption of mixed nuts on markers of energy metabolism in women with overweight/obesity. METHODS AND RESULTS: This is a randomized, controlled, and parallel clinical trial with adult women. In an acute study, participants received a beverage containing mixed nuts (30&#xa0;g of cashew nuts&#xa0;+&#xa0;15&#xa0;g of Brazil nuts) or a control beverage, and energy metabolism markers were assessed for up to 3&#xa0;h postprandially. For the chronic study, participants received 45&#xa0;g of a mix of nuts/day and a -500kcal energy-restricted diet (MNG) or only a -500kcal energy-restricted diet free of nuts (CTG) for 8 weeks, and energy metabolism was assessed before and after the intervention period. In the postprandial period, fat oxidation was higher in the MNG than in the CTG (piAUC: 47.53&#xa0;&#xb1;&#xa0;5.78&#xa0;mg/min vs. 27.93&#xa0;&#xb1;&#xa0;6.98&#xa0;mg/min; p&#xa0;=&#xa0;0.048). After 8 weeks of the intervention, fasting fat oxidation increased in the MNG (+16.0&#xa0;&#xb1;&#xa0;7.0&#xa0;mg/min) and decreased in the CTG (-5.0&#xa0;&#xb1;&#xa0;6.0&#xa0;mg/min), with no significant difference between groups. Other acute and chronic markers also showed no significant changes between groups. CONCLUSION: The acute consumption of mixed nuts increased postprandial fat oxidation, whereas chronic intake within an energy-restricted diet did not affect energy metabolism markers in women at cardiometabolic risk. REGISTRATION NUMBER FOR BRAZILIAN REGISTRY OF CLINICAL TRIALS: RBR-3ntxrm.

Humans

Transcriptomic responses of Porphyrophora sophorae larvae during licorice root colonization reveal coordinated remodeling of translation, mitochondrial energy metabolism and defense-related genes.

BACKGROUND: Porphyrophora sophorae is a subterranean piercing-sucking scale insect that damages licorice (Glycyrrhiza uralensis) roots, but the molecular responses associated with larval root colonization remain insufficiently defined. METHODS: We compared non-parasitic larvae (NP) and root-colonizing larvae (RC) using six RNA-seq libraries, de novo transcriptome assembly, DESeq2-based differential expression analysis, GO/KEGG enrichment, annotation-based candidate gene screening, and RT-qPCR validation of selected genes. RESULTS: Sequencing yielded 260.91 million clean reads, and de novo assembly produced 60,794 non-redundant transcripts. DESeq2 identified 703 FDR-significant DEGs, including 49 upregulated and 654 downregulated genes in RC larvae. Upregulated genes were mainly associated with translation- and ribosome-related processes, whereas downregulated genes were enriched in mitochondrial, oxidation-reduction, energy metabolism, and oxidative phosphorylation-related functions. Annotation-based screening identified 75 FDR-significant candidate genes associated with chemosensation, defense-related responses, and energy metabolism, with mitochondrial energy metabolism-related genes forming the largest module. RT-qPCR validation based on the raw Ct data showed concordant expression directions for ten selected transcript targets. CONCLUSIONS: Root colonization in P. sophorae larvae was associated with coordinated transcriptional remodeling involving selective activation of translation-related processes, adjustment of mitochondrial energy metabolism, and changes in defense-related gene expression. These results provide candidate molecular targets for future functional studies of host contact, feeding establishment, and physiological adjustment in this subterranean scale insect.

Animals

Mineral-driven molecular signatures of energy metabolism underpin sperm motility in buffalo.

The success of spermatogenesis depends on the interplay of various biomolecules that ultimately determine sperm quality. In this study, RNA-seq analysis of frozen-thawed buffalo sperm (n&#x202f;=&#x202f;8) revealed the presence of 263 mineral-associated genes (>1 FPKM) in high (n&#x202f;=&#x202f;4) and 181 in low motile (n&#x202f;=&#x202f;4) sperm groups. Among these, 177 mineral-associated genes were commonly expressed between them, and the majority were upregulated (>1 fold), LOC102391588 (ncRNA; 37-fold), ZNF699 (26.5-fold), MYZAP (13-fold), etc., in the high motile group. The expression of selected mineral-associated genes was validated. The top enriched functions in commonly expressed genes were regulation of transcription by RNA polymerase II (FDR: 4.7&#x202f;&#xd7; 10&#x207b;2; ZNF331, ZNF692, ZNF180, etc.), followed by spermatogenesis (FDR: 2.9&#x202f;&#xd7; 10&#x207b;2; CALR3, ADAM18, ADAM29, etc.), proton transmembrane transport (FDR: 4.0&#x202f;&#xd7; 10&#x207b;2; ATP6V0E1, ATP1A4, ATP6V1B2, etc.) and flagellated sperm motility (FDR: 2.3&#x202f;&#xd7; 10&#x207b;1; CATSPERD, EFCAB6, CABS1, etc.). Additionally, the chromatin remodeling pathway (FDR: 3&#x202f;&#xd7; 10&#x207b;2; PTP4A1, PPM1A, DUSP1, etc.) emerged as the most significant and may suggest that these minerals influence genome packaging and sperm functionality. Mineral-associated genes were predominantly associated with zinc (49%), followed by calcium (20%), phosphorus (10%), iron (5%), sodium (2%), potassium (2%), copper (1%) and other trace elements (11%). Although the current study uses frozen-thawed sperm, the findings indicate that mineral-associated genes are crucial for promoting membrane stability, energy production, motility and chromatin integrity, which may contribute to the superior fertilizing ability of sperm.

Animals

Dual-tasking reveals severity-dependent reorganization of cortical beta energy landscapes in Parkinson's disease.

Dual-task impairment is a hallmark of Parkinson's disease (PD), yet the large-scale neural mechanisms underlying postural-motor interference remain poorly understood. In particular, it is unclear how cortical network dynamics reorganize across disease severity when postural control competes with concurrent task demands. This study investigated EEG-derived beta-band cortical energy landscapes in healthy older adults, early-stage PD, and mid-stage PD during single- and dual-task conditions. Dual-task behavioral cost increased with disease severity for concurrent manual performance (p&#xa0;<&#xa0;0.001), whereas a quadratic pattern was observed for postural performance. Energy landscape analysis revealed severity-dependent reconfiguration of cortical beta dynamics. Dual-task-related landscape changes in effective network flexibility (&#x394;Neff), landscape geometry (&#x394;Evar and &#x394;Gmag), and dominant low-energy attractor organization (&#x394;Low mass and &#x394;Low area) showed significant monotonic trends (p&#xa0;<&#xa0;0.05), reflecting progressive constrained cortical network dynamics with advancing PD severity. In addition, dual-task-related landscape alterations were associated with clinical severity, as indexed by Hoehn and Yahr stage (|r|&#xa0;=&#xa0;0.353-0.423, p&#xa0;=&#xa0;0.016-0.048), and showed associations with motor impairment, as measured by MDS-UPDRS part III scores (|r|&#xa0;=&#xa0;0.333-0.455, p&#xa0;=&#xa0;0.009-0.063). These findings demonstrate that dual-task demands induce severity-dependent reconfiguration of cortical beta energy landscapes in PD. Energy landscape geometry may capture systems-level neural constraints associated with dual-task susceptibility in PD, providing a physiologically grounded framework to characterize disease-related functional vulnerability.

Humans

An expanded breakfast buffet increases daily energy and protein intakes in hospitalised patients: A prospective crossover quality improvement study.

BACKGROUND & AIMS: Inadequate dietary intake remains common during hospitalisation. Ordinary hospital meals are central to nutritional intake, but their contribution depends on what is offered and what patients are able and willing to eat. We evaluated whether a preference-informed, limited expansion of the hospital breakfast buffet could increase total daily energy and protein intakes. METHODS: This prospectively structured, ward-based crossover quality-improvement study was conducted in seven inpatient wards at a tertiary university hospital. Each ward was observed for four consecutive days and randomly allocated to begin with standard or expanded breakfast, after which conditions alternated daily. The expanded buffet consisted of standard breakfast supplemented with familiar energy- and protein-rich foods selected from previous patient-choice data. Twenty-four-hour intake was registered using component-level weighed food records during the day and nursing registration overnight. Primary outcomes were total daily energy and protein intakes. Linear mixed-effects models adjusted for observation day and ward-level starting sequence and accounted for repeated patient observations and ward-level clustering. Analyses used data from patients who consumed breakfast and contributed analysable observations under both breakfast conditions. RESULTS: The primary crossover population included 71 patients contributing 188 analysable patient-days. Compared with standard breakfast, the expanded breakfast increased total daily energy intake by +198 kcal/day (95% CI 44 to 352) and protein intake by +6.8 g/day (95% CI 1.0 to 12.5), without a statistically significant increase in total food weight. Daily energy and protein adequacy increased by +8.7 and + 6.8 percentage points, respectively. The increase was driven mainly by breakfast intake, with no measurable reduction in non-breakfast intake. CONCLUSIONS: A limited expansion of the ordinary hospital breakfast buffet increased total daily energy and protein intakes in the primary crossover population of hospitalised adults who consumed breakfast. This increase occurred without a statistically significant increase in total food weight or a measurable reduction in non-breakfast intake. Small, preference-informed additions of familiar energy- and protein-rich foods at breakfast may improve daily intake by increasing the nutrient yield of foods patients are able or willing to eat.

Humans

Associations Between Health-Related Physical Fitness and Accelerometry-Based Energy Expenditure in Physiotherapy Workers.

BACKGROUND AND PURPOSE: Although it has been assumed that higher physical activity (PA) levels will contribute to better physical fitness (PF) performance, the interplay between these two has yet to be investigated. Moreover, the majority of studies have been presented in children and adolescents, and older adults, while little is known about the correlation in the adult working population of physiotherapists. Therefore, the main purpose of the study was to examine associations between objectively measured PA and health-related PF. METHODS: We recruited 50 physiotherapists (72.6% women) from several public and private settings in the city of Zagreb. The SenseWearArmbandPro3 (SWA), a triaxial accelerometer placed on the nondominant hand for 7 consecutive days, was used to capture total energy expenditure (TEE) and active EE (AEE). Cardiorespiratory fitness included the Harvard step test, and muscular fitness was composed of sit-ups in 60&#xa0;sec and the Handgrip strength. Flexibility was evaluated using the Toe-touch test. RESULTS: TEE and AEE were moderately and positively correlated with the Harvard step test (r&#xa0;=&#xa0;0.65 and 0.62, p&#xa0;<&#xa0;0.001), sit-ups (r&#xa0;=&#xa0;0.70 and 0.59, p&#xa0;<&#xa0;0.001), and the Handgrip strength test (r&#xa0;=&#xa0;0.74 and 0.64, p&#xa0;<&#xa0;0.001). No significant correlation with the Toe-touch test was observed (r&#xa0;=&#xa0;-0.25 and -0.19, p&#xa0;>&#xa0;0.05). When models were adjusted for age, weaker, but significant positive correlations remained. DISCUSSION: The findings suggest that both cardiorespiratory and muscular fitness are positively associated with PA, whereas no statistically significant association with flexibility was detected. Thus, it is not surprising that we obtained moderate to almost strong correlations between TEE and AEE with cardiorespiratory and muscular fitness. CONCLUSIONS: In physiotherapists, TEE and AEE yield moderate correlations with health-related PF, especially for cardiorespiratory and muscular fitness.

Humans

Integrated proteomic and acetylomic analyses reveal the metabolic reprogramming associated with increased tylosin-equivalent concentration in Streptomyces xinghaiensis sf106-B1.

Deciphering the metabolic basis of high-yield antibiotic production in Streptomyces is crucial for strain optimization. Atmospheric and room-temperature plasma (ARTP) mutagenesis of Streptomyces xinghaiensis sf106 generated a mutant with a 30% increase in tylosin-equivalent concentration (&#x3bc;g/mL). 4D-FastDIA quantitative proteomics identified 279 differentially abundant proteins enriched in the Type I polyketide synthase (PKS) pathway, with increased abundance of key macrolide-biosynthesis-related proteins. Lysine-acetylome profiling identified 1152 differentially abundant acetylation sites and revealed altered acetylation of enzymes involved in fatty acid metabolism and the tricarboxylic acid (TCA) cycle, suggesting adjustments in central metabolism associated with acyl-CoA precursor availability and energy generation. Integration of proteomic and acetylomic data suggests coordinated changes in protein abundance and lysine acetylation associated with the increased tylosin-equivalent concentration. These results highlight candidate nodes for rational metabolic engineering of S. xinghaiensis.

Streptomyces

Water intake, switching between bites and sips, and drinking behavior are associated with food intake across meals varying in spiciness: A secondary analysis of two randomized crossover studies.

Widespread nutrition advice instructs consumers to drink water with meals to increase fullness and reduce energy intake. However, recent data indicates greater water intake is associated with more food intake at a meal, not less. Switching between meal components (e.g., alternating between food and water), has also been associated with increased food intake at a pasta meal, but it remains unclear whether this applies to other foods. In a secondary analysis, we pooled existing data from 2 crossover experiments (total n&#xa0;=&#xa0;86) where adults ate an ad libitum lunch consisting of 650&#xa0;g of beef chili (n&#xa0;=&#xa0;52) or chicken tikka masala (n&#xa0;=&#xa0;34) with 450&#xa0;g of water twice in the laboratory while being video-recorded. For both experiments, the spiciness of the lunch was varied by adding different ratios of hot:sweet paprika. Videos were coded to measure sip number, sip size (g/sip), drinking rate (g/min), and number of switches between bites of food and sips of water. As we previously reported, increasing spiciness slowed eating rate and reduced food intake; in secondary analyses described here, the reduction in food intake was not moderated by water intake, switching, or drinking behaviors (all p&#xa0;>&#xa0;0.73). Notably, across all meals, greater water intake (p&#xa0;<&#xa0;0.001) and switching (p&#xa0;=&#xa0;0.02) associated with greater food intake. Overall, individuals ate more when they drank more and switched between bites and sips more often, highlighting the potential influence of water and drinking behaviors on food consumption. This finding challenges the widespread dietary advice to drink water with meals to reduce food intake.

Humans

The environmental impact of diagnosis and therapy in obstructive sleep Apnea: A systematic review.

Healthcare contributes significantly to global greenhouse gas (GHG) emissions, yet the environmental impact of sleep medicine, particularly the diagnosis and therapy of obstructive sleep apnea (OSA), remains poorly characterized. We systematically searched PubMed, Scopus, and Embase (2015-2025) for studies on OSA care reporting environmental metrics (carbon footprint, energy use, resource consumption) or healthcare resource utilization. Supplementary searches identified additional non-peer-reviewed sustainability-focused studies that have been presented at conferences. Of 19 primary peer-reviewed studies on OSA care and utilization, only one reported environmental metrics (telemedicine CO2 savings related to reduction in travel-related emissions). Supplementary sources revealed that OSA care has a measurable carbon footprint driven by disposable equipment, device electricity, and travel and that OSA diagnostics create significant solid waste with opportunities for waste reduction through the use of reusable equipment. This review shows that while the environmental impact of sleep medicine has been rarely studied to this date, available evidence suggests significant opportunities for sustainability through virtual care, home testing, and equipment optimization. Future research should incorporate environmental impact into the assessment of clinical pathways.

Humans

Exploring the role of successful exercise-induced body weight loss on cardiometabolic health in individuals with metabolic syndrome.

BACKGROUND AND AIM: High-intensity interval training (HIIT) is known to improve cardiorespiratory fitness (i.e., VO2MAX), a key marker of cardiometabolic health in individuals with metabolic syndrome (MetS). Nonetheless, body weight loss is widely recognized as a crucial factor in reducing insulin resistance and improving metabolic risk factors. Thus, we aimed to determine the importance of body weight loss following exercise training on improving MetS. METHODS AND RESULTS: Two hundred and twenty-eight adults (55.3&#xa0;&#xb1;&#xa0;7.9&#xa0;yr) with overweight/obesity (32.5&#xa0;&#xb1;&#xa0;4.6&#xa0;kg&#xb7;m-2) and MetS were randomized to: a) standard health care non-exercise group (CONTROL group, N=58) or b) standard health care plus 16 weeks of HIIT (EXER group, N=170). MetS (MetS z-score), insulin resistance (HOMA-IR), cardiorespiratory fitness (VO2PEAK), maximal cycling power (WPEAK), and body weight/composition were assessed. After intervention, EXER group participants were divided according to their weight loss response to training: i) those achieving the weight loss predicted from estimated exercise energy expenditure (-BW group, n=78; -3.3&#xa0;&#xb1;&#xa0;2.2&#xa0;kg); ii) those not reaching the expected weight loss (=BW group, n=38; -0.7&#xa0;&#xb1;&#xa0;0.5&#xa0;kg); iii) and those who gained weight (+BW group, n=54; 1.1&#xa0;&#xb1;&#xa0;1.0&#xa0;kg). VO2PEAK significantly improved regardless of body weight loss response (-BW, 0.3&#xa0;&#xb1;&#xa0;0.3; =BW, 0.2&#xa0;&#xb1;&#xa0;0.3; +BW, 0.3&#xa0;&#xb1;&#xa0;0.2&#xa0;L&#xb7;min-1; all p&#xa0;<&#xa0;0.001) compared to CONTROL group (0.0&#xa0;&#xb1;&#xa0;0.3&#xa0;L&#xb7;min-1). However, significant improvements in MetS z-score (-0.31&#xa0;&#xb1;&#xa0;0.41) and HOMA-IR (-0.7&#xa0;&#xb1;&#xa0;1.6) were observed only in the -BW group (both p&#xa0;<&#xa0;0.001). CONCLUSIONS: Exercise recommendations should consider that greater improvements in MetS are observed when interventions are accompanied by successful body weight loss. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05120778.

Humans

Risk factors for loss of skeletal muscle mass in patients with chronic kidney disease on a low-protein diet.

OBJECTIVES: A low-protein diet (LPD) is recommended for patients with chronic kidney disease (CKD) to prevent a further decline in renal function. However, its impact on muscle mass in these patients remains unclear. This study investigated the risk factors for loss of muscle mass in patients with CKD on an LPD. METHODS: Eighty-four patients with predialysis CKD (59 men, mean age 61.9 &#xb1; 11.5 y) who participated in a multicenter randomized controlled trial initiated in 2014 were retrospectively reviewed. We collected data on baseline blood and urine tests, body composition, and dietary records at the start and end of the observation period. We evaluated muscle mass using the skeletal muscle index (SMI) and analyzed risk factors for a decrease in SMI during the 24-wk observation period, using logistic regression analysis. Variables with an association (P < 0.1) in univariate analysis, as well as age, sex, use of low-protein rice, and changes in protein intake, were subjected to multivariate analysis. RESULTS: SMI decreased in 50 patients (59.5%) during the observation period. Multivariate analysis identified significant associations of the SMI with serum albumin at baseline (odds ratio 0.11, 95% confidence interval 0.02-0.52, P = 0.004) and changes in energy intake while on the LPD (odds ratio 3.39, 95% confidence interval 1.00-11.43, P = 0.049). CONCLUSIONS: Risk factors for reduced SMI in patients with CKD on an LPD were malnutrition when initiating the LPD and reduced energy intake during its implementation. Clinicians should optimize nutritional status before initiation of an LPD and ensure adequate energy intake throughout treatment.

Humans

An updated systematic review of buffalo nutritional requirements (2000-2024).

Buffaloes (Bubalus bubalis) are large ruminants with a superior ability to digest and utilize low-quality forages, producing milk and meat of higher quality compared to cattle. Despite their importance in animal production, buffaloes remain the focus of relatively few studies aimed at defining their nutritional requirements, which often results in inadequate diet formulation and management. There, this study aimed to conduct a systematic review of the literature on buffalo nutritional requirements, considering only open-access papers published in English and in indexed journals. A total of 58 studies met the inclusion criteria. Most of them focused on dairy buffaloes, particularly on the evaluation of crude protein, energy levels, and fiber content in the diet. Mineral nutrition was addressed in eight studies; however, in general the evaluated levels showed no significant effects. In contrast, very few or no studies were found concerning beef buffaloes, growing animals, reproduction, or other production stages. These findings highlight a critical gap in the literature and reinforce the urgent need to direct more research efforts and resources toward establishing species-specific nutritional requirements, particularly for beef buffaloes.

Animals

Acute Stevia Consumption does not Alter Endocrine Responses in Individuals with Normal Weight, Overweight, and Type 2 Diabetes Mellitus.

BACKGROUND: Stevia is a plant-based non-nutritive sweetener. Acute effects of stevia ingestion on glycemia and hormonal responses have not been fully investigated. OBJECTIVE: This objective of this study was to evaluate the acute effects of beverages containing stevia alone and in combination with glucose on glycemic, hormonal, and appetite responses. METHODS: This study evaluated three cohorts of n=23 individuals with either normal weight (NW), overweight (OW), or type 2 diabetes mellitus (T2DM) for which each individual completed four test conditions in a randomized sequence crossover study design. The four test conditions were beverages containing stevia (75.6 mg steviol equivalents), water, glucose (30 g), and stevia+glucose (30 g glucose+75.6 mg steviol equivalents). Blood samples were collected before and for 180 min after beverage consumption. Assessments included net area under the curve (niAUC) and incremental maximal concentration values for plasma glucose, insulin, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1, glucagon, and PYY. Appetite was assessed with visual-analog scale questions and energy consumption during an ad libitum meal. RESULTS: Responses to the stevia beverage did not differ significantly from those for water alone, and stevia + glucose did not differ significantly from glucose alone for any of the three groups. CONCLUSION: Acute stevia consumption did not materially alter responses for glycemia or hormones involved in glucose and appetite regulation, appetite ratings, or energy intake at a subsequent meal. Clinical Trial Registry number and website where it was obtained: Clinical Trials.gov Identifier: NCT05287906. Study Details | NCT05287906 | A Trial to Assess Steviol Glycosides on Acute Appetite Hormone Release | ClinicalTrials.gov.

Appetite

Physiological and molecular responses of coelomocytes to low- to mid-frequency acoustic exposure in the sea urchin Strongylocentrotus intermedius.

Underwater noise is a widespread environmental pollutant in marine ecosystems, yet the effects of low- to mid-frequency acoustic exposure on immune physiology and molecular responses in echinoderms remain unclear. In this study, the sea urchin Strongylocentrotus intermedius was exposed to continuous pure-tone acoustic stimulation at 80, 125, 250, 500, 750, and 1000&#xa0;Hz for 3&#xa0;h. Results showed that acoustic exposure significantly affected redox homeostasis, energy metabolism, and immune function in S. intermedius coelomocytes: the antioxidant system and glutathione redox balance were altered, as indicated by increased superoxide dismutase (SOD) and catalase (CAT) activities, elevated reduced glutathione (GSH) content, and a higher GSH/GSSG ratio; glycolysis-related enzyme activities were enhanced, with increased pyruvate kinase (PK) activity under 125-500&#xa0;Hz exposure and elevated hexokinase (HK) activity at 250&#xa0;Hz; and immune function was impaired, as shown by increased coelomocyte mortality, reduced phagocytic activity, and inhibited acid phosphatase (ACP) and alkaline phosphatase (AKP) activities, whereas respiratory burst activity showed no significant change. Among all treatments, 250&#xa0;Hz induced the most pronounced physiological responses. Transcriptomic analysis of coelomocytes from the 250&#xa0;Hz group identified 663 differentially expressed genes, including 537 upregulated and 126 downregulated genes, mainly enriched in pathways related to apoptosis, phagosome, lysosome, glutathione metabolism, arachidonic acid metabolism, and carbohydrate metabolism. These findings indicate that low- to mid-frequency acoustic exposure can act as a physiological and molecular stressor to S. intermedius coelomocytes by affecting redox homeostasis, enhancing energy metabolism, and suppressing immune effector processes, with 250&#xa0;Hz showing the strongest effect under the present exposure conditions. This study provides experimental evidence for evaluating the potential biological effects of low- to mid-frequency acoustic exposure on benthic echinoderms.

Animals

Plasticity of hepatic metabolism in Arctic char (Salvelinus alpinus) in response to cyclic hypoxia.

The emergence of cyclic hypoxia puts aquatic organisms' homeostasis under significant strain. Energetic metabolism as well as protein synthesis and folding are particularly altered during hypoxia, while reoxygenation imposes an oxidative challenge. Currently, little is known about how hypoxia-sensitive organisms respond to large oxygen fluctuations. Our previous work on Arctic char revealed that this salmonid, despite being strongly affected by acute hypoxia and reoxygenation (H/R), can successfully reestablish homeostasis, notably through adjustments to hepatic mitochondrial metabolism. However, the mechanisms underlying this acclimation remain poorly understood. We hypothesized that Arctic char remodel their hepatic proteome to optimize energy metabolism, reorganize oxygen-demanding pathways, and maintain cellular homeostasis during repeated H/R cycles. By exposing Arctic char to two or fifteen days of diel cyclic hypoxia, we confirmed this species' limited capacity to respond to acute H/R. Nevertheless, after fifteen cycles, fish adjusted their energetic metabolism through coordinated regulation of carbohydrate and lipid pathways and upregulation of amino acid metabolism. Mitochondrial metabolism was strongly reorganized, particularly at the ubiquinone-Complex III interaction level, alongside adjustments in proline utilization and protein processing. Moreover, protein processing and folding pathways were stimulated in both mitochondria and the endoplasmic reticulum. However, chronic cyclic hypoxia may still promote non-mitochondrial ROS production, DNA replication stress, and impaired immune function. This study highlights how a hypoxia-sensitive fish progressively reorganizes its metabolism and oxygen-demanding pathways to establish a phenotype adapted to chronic cyclic hypoxia, while also revealing the physiological costs associated with this acclimation.

Animals