Physiology & Behavior

Unpredictable and insufficient access to food, known as food insecurity, is associated with the development of obesity. However, causal mechanisms underlying this paradoxical relationship remain poorly understood. Using a rat model of food insecurity, this study investigated whether food insecurity causes dysregulated feeding behaviours, specifically impaired gut signal sensitivity and enhanced cue-driven appetitive responses. Adolescent female rats were assigned to receive either ad libitum chow access (Food secure), 90% caloric restriction (Food restricted) or unpredictable quantity and timing of food access (Food insecure), for 4 weeks. After which, rats were returned to an ad libitum chow diet for the remainder of the study. To examine gut signal sensitivity, we measured the effects of cholecystokinin (CCK) on 10% sucrose intake. To examine cue-driven feeding behaviours, we used Pavlovian appetitive conditioning and measured appetitive responses towards a food-predictive cue. Results showed that prior food insecure rats were less sensitive to the intake inhibitory effects of CCK and exhibited enhanced cue-induced appetitive behaviours, when compared to food secure and food restricted groups. Anxiety-like behaviours or learning and memory was not different between groups. At the end of the study, adolescent caloric restriction resulted in reduced fat mass, plasma leptin levels and body weight when compared to food secure, but not food insecure rats, suggesting that adolescent food insecurity somewhat overcame these metabolic effects. Taken together, our findings suggest that adolescent food insecurity impaired gut signal sensitivity and heightened food cue sensitivity, which may cause enduring metabolic and behavioural adaptations that promote overeating and weight gain.

Dietary choice plays a critical role in metabolic and neurological health, yet the biological factors that shape macronutrient preference remain poorly understood. Evidence from both humans and rodents suggests potential sex differences in the attractiveness of specific nutrients, though findings have been inconsistent and often rely on self-report or diets with mixed macronutrient composition. The present study examined sex differences in macronutrient preference and food-directed behavior in mice using a controlled three-food choice paradigm. Adult male (n = 12) and female (n = 11) C57BL/6J mice were given simultaneous access to foods consisting of fat, sucrose, or a fat-carbohydrate combination across 14 days. Intake, latency to approach, and time spent near each food source were quantified, and estrous cycle stage was monitored in females. Female mice consumed significantly more food than males overall, driven by a selective increase in fat intake. Behavioral measures paralleled these results, with females spending more time in proximity to fat-associated food zones. In contrast, males preferentially consumed the fat-carbohydrate combination and showed weaker nutrient-specific engagement. Estrous cycle stage modestly influenced feeding behavior, with estrus associated with increased overall intake and greater consumption of combination diets, reflecting elevated carbohydrate intake. These findings demonstrate robust sex differences in macronutrient preference and suggest that hormonal state may selectively modulate nutrient-specific feeding behavior.

Standard rat housing may impede species-typical behaviors and impact rat welfare and research outcomes. This research investigated the effects of housing on behavioral and physiological outcomes of rats through the use of modified large animal cages for housing, and was conducted in two studies. Study A: 70 Sprague Dawley (SD) rats (34 males, 36 females; 5 wk old) were randomly assigned to standard polycarbonate shoebox cages (C: 733.9cm2) or modified stainless steel primate cages (T: 10,416cm2) for 18 days. In Study B: 48 SD rats (24 males, 24 females; 7.5 wk old) were held in T housing for 90 days to assess long term impacts. All rats received gentle handling for 15s 3x/week. Rats were assessed for body weight, anxiety-like behavior in an elevated plus maze, response during a voluntary human approach test, and overall home cage behavior, posture, and space usage. Data were analyzed using generalized linear mixed models, with sex and treatment as fixed effects, and cage as the random effect. The results of study A suggest that the modified large animal cages (T) had positive impacts on rat behavior and welfare. T rats were less anxious (P=0.038) and more active (P<0.0001) and explorative (P=0.0003) compared to C rats. In both groups, activity levels declined towards the end of the 18-day study period (P<0.0001). For study B, similar patterns were observed, with rats becoming more inactive (P<0.0001) over 90 days. However, rats spent significant time on elevated shelves in T housing, which increased throughout the study (P<0.0001), suggesting continued use of the resources the housing provided. In both studies, there were no differences in latency to approach humans (P>0.05), but T rats spent less time in contact with human handlers, suggesting differences in motivation to interact with humans that should be explored further.

Of the three dietary macronutrients, protein plays an especially pivotal role in physiological functions. Nevertheless, the behavioural control of protein intake is poorly understood. In this study, we used Feeding Experimentation Devices (FED3s) to examine the structure of ingestive behaviour in mice given access to diets varying in protein content. Adult C57BL/6NRj mice were contact-housed in pairs in custom-made cages with perforated dividers, each having access to an individual FED3 unit. Mice were given ad libitum access to either 20 mg control, non-restricted (NR) pellets (20% casein) or 20 mg protein-restricted (PR) pellets (5% casein) from FED3s on free-feeding mode. Each pellet retrieval event was timestamped ~24 h/day. All mice experienced both diets for 7 days with order of diet presentation counterbalanced (i.e., NR[-&gt;]PR and PR[-&gt;]NR). Analysis of dynamics of pellet intake per day revealed that mice that were initially protein-restricted first showed a decrease in pellet intake before increasing on later days and exhibiting a persistent high level of intake once non-restricted diet was available. The group that was initially non-restricted exhibited a blunted response to the same diet manipulation. In addition, we clustered pellet retrieval data into discrete clusters of feeding events and used a mathematical approach to determine the boundary of meals (2-5 pellets), separated from "snacks" (1 pellet) and "feasts" (>5 pellets). We identified alterations in meal patterning in response to diet manipulation with protein restriction increasing "snacking" and leading to increased meal number, and reduced meal size. Moreover, restored access to NR diet, elicited "feasting". These effects depended on the sequence of diets the mice experienced, such that the effects were stronger in initially protein restricted mice compared to those initially non-restricted. In summary, our findings show that manipulation of dietary protein levels affects meal patterning in adult mice.

BackgroundObesogenic diets (ODs) are known to trigger metabolic and inflammatory disturbances. However, the effects of short-term OD withdrawal on systemic and neuroinflammatory parameters remain unclear. ObjectivesThis study investigated the short-term effects of OD withdrawal on metabolic, inflammatory, and anxiety-like behaviours in young male Wistar rats. MethodsThree-week-old male Wistar rats were fed either a control (Ct, n=5) or high-sugar/high-fat (HSHF) diet for 14 days. Animals in the HSHF group were further divided into no-withdrawal (NWt, n=5) and withdrawal (Wt, n=5) groups, where Wt received a control diet for 48 hours. Food intake, body mass, adiposity, serum metabolic parameters, hepatic energy stores, inflammatory markers (serum, liver, hypothalamus, hippocampus, mesenteric fat), and oxidative stress markers in the hippocampus were measured. Anxiety-like behaviour was assessed using the elevated plus maze. ResultsOD intake significantly increased caloric intake, visceral adiposity, hepatic glycogen, and TAG levels. The 48-hour withdrawal reduced TAG, induced hyperinsulinemia and hypoglycaemia, and heightened inflammation in mesenteric fat, serum, and the hippocampus. Oxidative stress markers (SOD and MDA) increased in the hippocampus, correlating with elevated serum corticosterone and heightened anxiety-like behaviour in the Wt group compared to the other groups. ConclusionShort-term withdrawal after only two weeks of OD intake exacerbates systemic and neuroinflammation, hippocampal oxidative stress, and anxiety-like behaviours, indicating rapid negative responses to dietary transition. These findings highlight the metabolic and behavioural challenges associated with short-term OD withdrawal and highlight the need for adjunct interventions to mitigate its adverse effects.

We assessed whether pigs provide consolation, referring to targeted affiliation that attenuates a partners stress, under experimental conditions that manipulated exposure to stressed partners. Using a within-subject design, 74 pigs were tested in three contexts: a helping task in which group members could observe and help a trapped focal pig to return to the group, a direct-reunion, in which group members were naive to the experience of a separated focal pig until reunion, and an undisturbed control. We measured affiliative and non-affiliative interactions, anxiety behaviours and changes in salivary cortisol. Only the helping context satisfied most consolation criteria: there were selective increases in unidirectional affiliative contacts from the observer to the focal pig, non-affiliative interactions remained at baseline, and focal pigs showed fewer anxiety behaviours. In contrast, direct-reunions triggered increases in affiliative and non-affiliative interactions and higher anxiety. Cortisol increased during both direct-reunions and helping, but its level was not linked to affiliation. Results add to growing evidence for consolation behaviour in pigs and suggest best practices for reintegrating pigs into groups. Graded reintroductions that allow observers to assess the emotional state of targets may promote social buffering, whereas abrupt regrouping may trigger more generalized arousal or personal distress.

Ramadan fasting represents a natural model of prolonged daily intermittent fasting associated with metabolic and circadian alterations. This study investigated longitudinal changes in intracortical excitability across pre-, mid-, and post-Ramadan timepoints in healthy adults observing Ramadan fasting. Thirty fasting participants underwent paired-pulse transcranial magnetic stimulation at three timepoints (pre-, mid-, and post-Ramadan). A non-fasting control group (n = 11) was assessed at pre- and mid-Ramadan. Conditioned motor-evoked potentials were recorded at interstimulus intervals of 2-10 ms and normalized to unconditioned responses. A linear mixed-effects model assessed effects of Timepoint and interstimulus interval (ISI). Secondary outcomes included blood glucose, cognitive performance, sleep duration, and reaction time. A significant main effect of Timepoint (p < 0.001) indicated longitudinal modulation of intracortical excitability, with increased MEP ratios at mid-Ramadan and partial persistence post-Ramadan. The ISI effect confirmed the inhibition-facilitation gradient (p < 0.001). The Timepoint x ISI interaction was not significant (p = 0.566), indicating a global shift in excitability without ISI-specific modulation. Blood glucose and sleep duration decreased significantly at mid-Ramadan. Ramadan fasting is associated with a time-dependent increase in intracortical excitability, most appropriately interpreted as a generalized shift rather than selective modulation of inhibitory or facilitatory circuits. These changes occur in the context of concurrent metabolic and sleep alterations and may reflect combined influences of fasting-related metabolic state and reduced sleep duration; however, these factors cannot be disentangled within the present design.

Endogenous circadian oscillators regulate learning, cognitive performance and memory are disrupted due to circadian shifts. High-fat-high-fructose (H) diet, photoperiodic shifts induced chronodisruption (CD) and a combination (HCD) causes neurobehavioral perturbations wherein; the merits of exogenous melatonin in alleviating the said behavioral deficits are studied herein. Indices of anxiety (marble burying test, elevated plus maze test and hole board test) and depressive behavior (sucrose preference test, forced swim test and tail suspension test) were elevated in H, CD and HCD groups. Significant increments in the titres of thyroid hormone levels (T3, T4 and TSH) and mRNA levels of hippocampal pro-inflammatory genes (Tnf-, Il-1{beta}, Il-4, Il-6, Il-10, Il-12, Il-17, Mcp-1 and Nf-{kappa}b) in the said experimental groups corroborates with the said changes. Exogenous melatonin treatment to the said experimental groups viz. HM, CDM and HCDM; accounted for moderate to significant improvement in the said neurobehavioral perturbations and hippocampal inflammatory markers. Hippocampal BDNF-TrkB pathway genes of H, CD and HCD had recorded a non-significant downregulation in mRNA but without prominent changes in proteins. Likewise, melatonin-treated groups showed moderate to significant improvement in transcripts of Bdnf, Trkb, Nt-3, Nt-4, Psd-95 and Syn-1. Herein, we report neurobehavioral perturbations caused by a combination of H and CD. Melatonin-mediated improvement in neurobehavior and the corrective changes in hippocampal BDNF-TrkB pathway implies towards the potential anxiolytic and anti-depressive activity as reported herein.

Prolonged esports play induces cognitive fatigue that is not fully captured by subjective awareness, motivating practical, non-stimulant nutritional strategies supported by objective physiological markers. We here tested whether acute milk protein intake attenuates fatigue-related physiological responses during prolonged esports play and supports subjective state, executive control, and in-game performance. In a randomized, single-blind (assessor-blind), energy-matched controlled crossover study, 15 healthy young adults with esports experience completed two sessions in which they consumed either a milk protein drink or an energy-matched apple juice control before a 3-h virtual soccer task. Physiological measures included pupillometry during gameplay, salivary cortisol, continuous interstitial glucose monitoring, and heart rate. Subjective ratings (VAS) and executive function (flanker task) were assessed across post-ingestion time points, and in-game performance metrics were aggregated within hourly gameplay blocks. Milk protein intake was associated with a coherent pattern of physiological advantages, including larger pupil diameter during gameplay, smoother interstitial glucose dynamics, and lower salivary cortisol, while heart rate showed time-dependent changes without a clear condition effect. These physiological changes co-occurred with higher enjoyment and lower hunger, improved flanker performance, and condition-dependent improvements in in-game performance, most notably higher shot success rate. Additionally, pupil diameter during gameplay was associated with inhibitory-control efficiency on the flanker task. These findings suggest that acute milk protein intake may serve as a practical, non-stimulant nutritional strategy to sustain physiological state and cognitive-behavioral performance during prolonged esports (virtual soccer) play. Highlights- Prolonged esports play models modern digital cognitive activity and cognitive fatigue. - Acute milk protein intake increases pupil diameter during prolonged esports play. - Interstitial glucose dynamics are smoother and salivary cortisol is lower with milk protein. - Enjoyment increases and hunger decreases during 3 h of virtual soccer play. - Executive function and in-game performance improve, most notably shot success rate.

Physical activity offers myriad benefits to health and well-being, in humans and other animals as well. In rodents, voluntary wheel running can attenuate the effects of both physical and social stressors on rodent social behavior. Whether wheel running affects rodent social behaviors per se remains less well understood. We conducted the current study to test whether home cage access to running wheels impacts the social behaviors of adult, group-housed C57BL/6J female mice during same-sex interactions with novel females. Group-housed females were either given continuous home cage running wheel access or a standard paper hut starting at weaning, and as adults, social behaviors were measured during interactions with novel females. In two cohorts, we found that 5 weeks of running wheel access during adolescence reduced the time that subject females spent investigating a novel female and also tended to reduce total ultrasonic vocalizations produced during interactions. These effects were not reversed by a 2-week period of running wheel removal but were recapitulated in a different cohort by 2 weeks of running wheel access in adulthood. Unexpectedly, we found that these effects on female social behavior were not due to wheel running per se, because females raised from weaning with immobile running wheels also showed low rates of social behaviors during same-sex interactions in adulthood. Overall, we find that the presence of a running wheel in the home cage has an enduring inhibitory influence on female social behavior during same-sex interactions, a finding that has implications for the design of studies that include same-sex interactions between female mice.

Oxytocin is a hypothalamic hormone and neuromodulator that has been linked to a variety of different functions, including parturition, social behavior, and cognitive processing. More recently, oxytocin has also been associated with metabolism and energy balance. However, evidence to date in this field has been inconsistent, especially in human research. To address this, we performed a preregistered systematic review and meta-analysis, which synthesized existing literature on the effect of exogenous oxytocin administration compared to a placebo on caloric intake and appetite in humans, using a living meta-analysis approach. Results indicated a significant, reductive effect of oxytocin administration on appetite in participants belonging to certain patient groups (e.g., obesity or type II diabetes; Hedges' g = -0.21). A separate moderator analysis evaluating oxytocin's effect on caloric intake revealed a conditional effect depending on the patient group, with the obesity group showing a significant effect. We did not find any statistically significant effects in healthy participants. However, further analyses revealed that these effects were also not equivalent, indicating that the data are currently too insensitive to draw clear conclusions. Taken together, the results provide some evidence for the role of oxytocin in regulating appetite in an anorexigenic, possibly homeostatic fashion. Future updates in this living meta-analysis may lead to more definitive conclusions.

In mammals, loud, high-pitched, and harsh-sounding calls typically accompany heightened emotional arousal, particularly during distress such as separation. However, whether subtle arousal reductions can be detected through acoustic analysis within a single negative context remains unclear. We investigated whether source-related acoustic parameters of puppy whines reflect arousal modulations induced by calming interventions during maternal separation. Thirty-five eight-week-old Beagle puppies were recorded under four conditions combining synthetic appeasing pheromone and a pressure harness. Vocal behavior, activity, whine duration, and intensity, did not significantly differ across treatments, suggesting interventions did not suppress separation-related vocal responses. Nevertheless, calming products selectively altered acoustic parameters known to index arousal in dog vocalizations. Puppies receiving combined treatments produced whines with lower fundamental frequency (fo) and reduced fo variability, while pheromone exposure increased call tonality, reflected by reduced jitter and shimmer and elevated harmonics-to-noise ratios. Spectral entropy remained unchanged, possibly because the proportion of whines containing nonlinear phenomena did not vary across conditions. Reductions in fo, fo variability, and acoustic roughness are consistent with established correlates of lower arousal in mammals, suggesting source-related vocal parameters sensitively capture subtle arousal shifts even when overt vocal behavior remains stable, supporting their use as bioacoustic indicators for evaluating welfare interventions.

There is a dearth of information on how different cocktails sweetened with different sugars impact brain activity. Glucose enters the brain faster and in greater concentration than fructose and directly affects neuronal activity of melanin-concentrating hormone (MCH) neurons. MCH signaling promotes both glucose drinking and alcohol intake by integrating central and sensory inputs, but it is currently unknown how MCH neuronal activity relates to sweetened cocktail drinking. This study sought to investigate the relationship between MCH activity and sugar-sweetened alcoholic cocktail drinking. We also sought to compare MCH neuronal responses to the sugar solutions without alcohol as well as their response to sensory stimuli. In female and male rats, we used fiber photometry to monitor MCH neurons in response to sensory stimuli and during drinking of 10% glucose, 10% fructose, and glucose or fructose cocktails with 1.25% or 10% alcohol. We found that MCH activity rises in response to a variety of sensory stimuli and peaks before the start of drinking for all cocktails, before returning to baseline near the start of drinking. The cocktail type impacted the dynamics of MCH activity, where increased alcohol concentration resulted in earlier MCH activity for fructose but not glucose cocktails. Finally, we found that peak MCH activity during drinking is correlated with approach behavior for all sugar and cocktail types. These findings suggest that glucose and alcohol may interact to directly influence MCH activity. Further, MCH neurons may regulate cocktail drinking in response to sugar type and alcohol concentration. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=118 SRC="FIGDIR/small/719280v1_ufig1.gif" ALT="Figure 1"> View larger version (17K): org.highwire.dtl.DTLVardef@54685org.highwire.dtl.DTLVardef@59003eorg.highwire.dtl.DTLVardef@11f0358org.highwire.dtl.DTLVardef@114b524_HPS_FORMAT_FIGEXP M_FIG C_FIG New and noteworthyFiber photometry was used to monitor lateral hypothalamic melanin-concentrating hormone (MCH) neurons in male and female rats during sensory stimuli and drinking of glucose, fructose, or glucose- or fructose-sweetened alcoholic cocktails. Subsecond-scale changes in MCH activity occurred after stimuli. Peak MCH activity during drinking was correlated with approach behavior. Alcohol concentration only impacted MCH activity with fructose cocktails. We discuss the implications of MCH dynamics towards brain function, associative learning, and alcohol use disorder.

Exercise affects the immune function and induces pro- and anti-inflammatory effects. The alterations concerning the immune system linked to physical activity have been documented across various studies with complex exercise tests. However, the characterization of the non-pathological, exercise-induced immunological stress regulation is highly relevant in numerous clinical and non-clinical areas for a better understanding of normal physiological adaptations and differentiation from non-healthy adaptations. Thus, it is valuable and necessary to establish simple immune-metabolic response triggering exercise tests for use in clinical and non-clinical settings. The aim of this study was to examine the effects of the 1-minute sit-to-stand test (STST) on immune-metabolic stress indices and to determine whether it elicits a sufficiently high intensity to qualify as an anaerobic exercise test, thereby supporting its application in investigating exercise-induced immunological stress regulation. 28 study participants performed the 1-minute STST. Capillary blood was taken 20 and 10 minutes before the test, immediately after, and 5, 10, 15, 30, and 45 minutes after exercise. Lactate, glucose and blood counts were determined. Lactate concentration increased significantly immediately after the STST (p < 0.001) and remained significantly elevated until 45 minutes post-exercise. Glucose concentration was significantly decreased after 10 minutes post-exercise (p < 0.05) and again 30 and 45 minutes post-exercise (p < 0.01 for both). Leucocyte count increased significantly post-exercise (p < 0.001) and returned to baseline levels 30 minutes afterwards. Lymphocyte and granulocyte count increased significantly after the test (p < 0.001 for both) and lymphocyte count slightly decreased below baseline values 30 minutes post-exercise (p = 0.07) while granulocyte count remained significantly elevated (p < 0.05). Furthermore, decreased NLR (p < 0.001) and SII (p < 0.01) immediately after the test and increased levels of NLR, SII and SIRI post-exercise could be observed. The 1-minute STST caused an increase in lactate level above the anaerobic threshold, therefore the test can be evaluated as an anaerobic exercise test. Furthermore, it was demonstrated that the STST induced shifts in leucocyte, lymphocyte, and granulocyte counts, which means that even a short intense anaerobic exercise, such as the STST causes changes in immune cell counts and therefore, the test is suitable for analyzing the exercise-induced immunological stress response.

Historically, the primary method for measuring murine circadian activity in vivo has been monitoring voluntary wheel running. Recently, passive infrared (PIR) motion sensors have emerged as an alternative that is not reliant on voluntary behaviour. While research has examined the differences between the two methods for measuring circadian parameters, little focus has been placed on how these techniques may confound the assessment of therapeutic interventions. Here, we show that wheel running activity is disproportionately affected by daily oral gavage of saline compared to sham gavage treatment. In contrast, PIR-monitored activity indicates little difference between the two treatments. Both PIR and running-wheel-measured activity show a reduction in circadian amplitude and an increase in intradaily variability during both types of gavage, likely reflecting the stress of daily gavage, though the mice showed no weight loss. This finding indicates that pre- and post-intervention comparisons will misattribute gavage effects to the intervention unless appropriate sham and vehicle controls are included. More broadly, the choice of circadian measurement technique fundamentally shapes the interpretation of pharmacological interventions and must be considered in experimental design.

ObjectiveStall housing of pregnant sows raises welfare concerns, whereas conventional group housing systems often reduce space efficiency. This study evaluated the effects of periodic group housing (PG) on reproductive performance and welfare compared with continuous stall housing (CS). MethodsSows in the CS group (n = 15) were continuously housed in stalls. In the PG group (n = 15), sows were housed in groups of three and allocated 1 day of group housing and 6 days of stall housing per week over 10 weeks. During group housing sessions, the sows had access to a group housing area containing sawdust. Behavioral observations and salivary cortisol measurements were conducted on the first day of the stall housing session in weeks 1, 6, and 10. Behavioral indices were expressed as proportions based on 90 sampling points recorded at 1-min intervals. ResultsThe number of stillbirths was significantly lower in the PG group than in the CS group (0.63 vs. 1.49 piglets per litter). whereas other reproductive outcomes, including total litter size and average birth weight, did not differ. In older parity sows, the PG treatment markedly increased the proportion of time spent lying, suggesting reduced discomfort associated with restricted movement. Furthermore, the proportion of exploratory behavior decreased markedly, and drinking behavior showed a decreasing trend across parity levels in the PG group, suggesting partial satisfaction of motivations for environmental exploration and oral manipulation. The proportion of oral abnormal behavior showed a pronounced interaction between housing treatment and experimental week, increasing from week 1 to week 6 in the PG group. Salivary cortisol concentrations did not differ between the groups. ConclusionPG may improve reproductive performance and partially satisfy the behavioral motivations restricted under continuous stall housing. This system may represent a practical alternative for improving animal welfare while minimizing economic losses.

BackgroundObesity is a chronic multifactorial disease characterized by substantial interindividual variability in weight loss after lifestyle intervention and bariatric surgery. Thyroid hormones play a key role in energy homeostasis, but their influence on postoperative weight outcomes remains insufficiently studied. ObjectiveTo evaluate the association between preoperative thyroid status and changes in body mass index (BMI) after lifestyle intervention and bariatric surgery over a five-year follow-up. MethodsWe conducted a retrospective cohort study including adults with class II or III obesity enrolled in the Obesite Severe et Epigenetique (OBESEPI) study. All participants underwent preoperative lifestyle intervention followed by bariatric surgery. Thyroid status was classified as euthyroid or hypothyroid based on clinical and biochemical criteria. BMI was assessed at baseline and at nine postoperative time points over five years. ResultsAmong 435 included patients, 71 (16.8%) had hypothyroidism. Baseline BMI was similar between groups, whereas diabetes was more frequent in hypothyroid patients (52.1% vs 37.7%; p = 0.022). Hypothyroid patients had significantly higher BMI at 6-24 months after surgery, but differences were no longer significant beyond three years. BMI trajectories and magnitude of weight regain were comparable between groups. Higher preoperative TSH levels were independently associated with BMI regain (OR 1.32, 95% CI 1.00-1.72; p = 0.047). Higher baseline BMI, younger age, and female sex were also associated with greater BMI regain. ConclusionsHypothyroidism was associated with lower early postoperative weight loss but did not influence long-term BMI trajectories. Higher preoperative TSH levels were independently associated with BMI regain. KEYPOINTSO_LIPreoperative hypothyroidism is associated with reduced early weight loss during the first two years after bariatric surgery. C_LIO_LILong-term BMI trajectories and weight regain patterns are similar between hypothyroid and euthyroid patients beyond three years of follow-up. C_LIO_LIHigher preoperative TSH levels independently predict BMI regain. C_LIO_LIBaseline BMI, younger age, and female sex remain key determinants of the magnitude of BMI regain after bariatric surgery. C_LI

Exercise is a positive health behaviour associated with improved mood. However, the mechanisms underlying the benefits of exercise on affective health are unclear, particularly with respect to type of exercise and sex. Chronic exercise decreases neuroinflammation, which is linked to improvements in mood and anxiety. However, exercise is also a physiological stressor that can transiently upregulate systemic inflammation, and its effects on neuroinflammation are not well understood. This study examined how acute and chronic exercise affect circulating and brain cytokine levels and anxiety-related behaviour in young healthy male and female mice. In Experiment 1, mice were placed on a treadmill for a two-hour bout of moderate exercise. Two hours after exercise, animals were either tested in the open field or euthanized for measurement of cytokines (IL-1{beta}, TNF, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12p70, IFN-{gamma}, KC/GRO). In Experiment 2, mice underwent an 8-week moderate treadmill exercise paradigm followed by open field testing and tissue collection. Acute exercise decreased time spent in the centre of the open field in males only, suggesting increased anxiety-like behaviour in males. Acute exercise increased IL-6 and decreased TNF in serum, and increased amygdala principal component 1 (loading IL-12p70, IL-10, IFN-{gamma}, and TNF) in both sexes. Chronic exercise increased open field centre entries, increased IL-6 in the prefrontal cortex, decreased TNF in the dorsal hippocampus, and had minimal effects on circulating cytokines in both sexes. These results demonstrate that the effects of exercise on anxiety-related behaviour and cytokine levels depend on recurrence, tissue, and brain region. New & NoteworthyOur work highlights the contrast between anxiogenic and anxiolytic effects of acute versus chronic exercise, respectively, in healthy mice. Acute and chronic exercise differentially affected circulating and brain cytokines, providing insight into physiological adaptations to exercise. Both sexes demonstrated similar cytokine responses to exercise. These similarities are novel with respect to exercise research and noteworthy given sex differences in anxiety with respect to acute exercise.

Despite growing availability of plant-based meat, limited data exist on how these products perform relative to animal-based options in real-world consumption settings. This study compares consumer sensory perceptions of two plant-based meatballs (soy, soy-wheat) and two animal-based meatballs (beef, beef-mushroom) among university dining hall patrons (n = 128), complemented by instrumental Texture Profile Analysis. Animal-based meatballs received significantly higher ratings for moistness, meatiness, fattiness, and tastiness (all p < 0.001), with the meatiness gap being the largest ({Delta} = 1.40 on a 5-point scale). Texture analysis found that animal-based samples were significantly harder, more cohesive, and chewier than plant-based samples. In contrast, consumers perceived no difference in chewiness or hardness between categories, revealing a disconnect between instrumental and sensory measures. Just-About-Right penalty analysis identified insufficient savoriness as a universal improvement target across all products, including beef. Flavor and texture were the dominant drivers of dining choice, while sustainability and animal welfare ranked lowest in importance. These findings indicate that achieving sensory parity--particularly in moistness, meatiness, and savoriness--rather than emphasizing sustainability messaging, may be critical for increasing acceptance of plant-based meat in institutional food service. Data and code are available at https://github.com/LivingMatterLab/AI4Food

Stressors are commonly used in rats to induce models of anxiety or depression. The effectiveness of these stressors is often evaluated using specific behavioural tests. In a previous meta-analysis of chronic variable stress (CVS) procedures, we predicted that longer and more intensive stress procedures would result in larger effect sizes in behavioural tests. However, we found that the duration or intensity of CVS procedures did not correlate strongly with the magnitude of the effect sizes reported in behaviouraltests. In that study, we were concerned that the large and unexplained diversity in CVS procedure design, both in terms of duration and the types of stressors used, made it challenging to detect the factors that were influencing effect size. In an effort to address this, we explore here the use of a much simpler stress procedure - chronic restraint stress (CRS) - to study the relationship between the duration of CRS procedures and the effect sizes obtained in subsequent behavioural tests. We searched PubMed for articles using CRS procedures with rats, systematically documented the total duration of restraint, and carried out a meta-analysis of the effect sizes obtained in four behavioural tests: the forced swim test (FST), the sucrose preference test (SPT), the elevated plus maze (EPM) and the open field test (OFT). We found that chronic restraint stress increased immobility in the FST, decreased sucrose preference in the SPT, decreased time spent in the open arms of the EPM but had no effect on time spent in the centre of the OFT. However, the effect sizes in all behavioural tests, except the SPT, were not moderated by the duration of the CRS procedure, indicating that longer CRS procedures are associated with larger effect sizes in the SPT but not in the FST or EPM.