Journal of thermal biology最新文献

{"title":"Numerical simulation study on the thermo-mechanical coupling damage mechanism in microwave ablation of lung tumors","authors":"Yujie Fu,&nbsp;Qun Nan","doi":"10.1016/j.jtherbio.2026.104404","DOIUrl":"10.1016/j.jtherbio.2026.104404","url":null,"abstract":"<div><div>Lung cancer is one of the most threatening malignant tumors globally, and microwave ablation (MWA) serves as a crucial minimally invasive approach for treating early-stage patients who are intolerant to surgery. However, the lung, as a typical porous medium, remains unclear in terms of the correlation mechanism between thermal stress evolution during MWA and postoperative complications such as cavities. This study aims to reveal the thermo-mechanical coupling damage mechanism during lung MWA through numerical simulation. Based on the porous medium theory and the two-phase lag heat transfer model, an electromagnetic-thermal-mechanical multiphysics coupled finite element model was constructed to simulate the complete ablation process of lung tumors using a 2450 MHz microwave antenna. The simulation results indicate the presence of two damage risk zones with distinct mechanical characteristics during MWA: the high-temperature core zone, which is dominated by thermal coagulation necrosis and phase change contraction, bears the highest equivalent stress; whereas the tissue transition zone, due to significant gradients in temperature and material properties, becomes a region where strain first increases and then decreases, accompanied by shear stress concentration, making it a high-risk area for tearing-type damage and potential cavity formation. During the cooling phase, significant redistribution and relaxation of stress occur in both the core and transition zones. The presence of residual strain and stress confirms that irreversible phase change damage is the primary mechanism responsible for the permanent volume reduction of the ablation zone. This study systematically elucidates the “dual risk zone” mechanism of thermo-mechanical coupling damage in lung MWA, reveals the importance of mechanical evolution during the cooling phase, and provides an important theoretical basis for developing precise and safe ablation strategies based on mechanical thresholds.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"136 ","pages":"Article 104404"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146157690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic component of sensitivity to heat stress for fertility traits of Jersey crossbred cattle","authors":"Indrajit Gayari ,&nbsp;Sylvia Lalhmingmawii ,&nbsp;Lalmalsawmi Colney ,&nbsp;Hasan Baneh ,&nbsp;Ajoy Mandal","doi":"10.1016/j.jtherbio.2026.104376","DOIUrl":"10.1016/j.jtherbio.2026.104376","url":null,"abstract":"<div><div>Heat stress (HS) attributed by climate change, is a significant challenge to livestock production globally, particularly affecting dairy cows' fertility. This not only leads to decreased reproductive performance but threatens the herd profitability. The aim of this study was to analyze the effect of heat stress on non-return rate (NR56) and conception rate (CR) in Jersey × <em>Bos indicus</em> crossbred cows, to identify the threshold at which these traits are affected, and to estimate genetic parameters and variance components under HS conditions. The study analyzed insemination records of 1174 crossbreds over a period of 26 years, with the use of temperature-humidity index (THI) as an indicator to measure HS. Logistic regression models and Bayesian statistics were employed to identify THI breakpoints (BP) for NR56 and CR. Genetic parameters were estimated using reaction norm models and Gibbs sampling approach for evaluation of variance components. THI breakpoints were identified at 77 for NR56 and 68 for CR. The heritability of NR56 decreased as THI increased, while CR heritability exhibited a peak at higher THI levels. Genetic correlations indicated antagonistic relationships between general additive and HS-specific additive effects for both traits, with increasing additive and environmental variance as THI rose. Thus, this study highlights the genetic diversity associated with heat tolerance in crossbred cows and suggests that selecting for genetically heat-tolerant animals may mitigate HS related fertility declines. Further, these findings provide insight into breeding strategies that can be implemented to enhance reproductive performance of crossbred dairy cow in tropical climatic conditions.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"136 ","pages":"Article 104376"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145980961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Critical thermal limits of Atlantic bluefin tuna (Thunnus thynnus) larvae","authors":"Marta Moyano ,&nbsp;Edurne Blanco ,&nbsp;Aurelio Ortega ,&nbsp;Fernando De la Gándara ,&nbsp;Laia Armengol ,&nbsp;Myron A. Peck ,&nbsp;Patricia Reglero","doi":"10.1016/j.jtherbio.2026.104410","DOIUrl":"10.1016/j.jtherbio.2026.104410","url":null,"abstract":"<div><div>There is a growing interest in understanding the thermal tolerance of ectotherms across life stages. Identifying the stages that are most sensitive can help develop more robust projections on the consequences of climate impacts to populations, as well as help guide management and conservation efforts. Here, we estimate upper and lower thermal tolerance (as Critical Thermal maximum, CTmax, and minimum, CTmin) of Atlantic bluefin tuna (<em>Thunnus thynnus</em>) larvae. This species is an iconic apex predator that exhibits regional endothermy during the adult stage, but thermal tolerance of larvae was unknown. CTmin and CTmax were estimated in larvae grown from wild eggs under laboratory conditions. The mean (±SE) CTmax and CTmin across all tested batches and developmental stages was 31.7 (±0.6) and 17.9 (±0.7)°C, respectively. Rate of temperature change (1.5, 3, 6, or 9 °C h⁻¹) had no effect on the thermal tolerance estimates. Similarly, CTmin and CTmax were consistent across preflexion, flexion, and postflexion larval stages. The observed high inter-individual variability in CTmin and CTmax (11-13 °C) likely reflects methodological challenges related to the extreme sensitivity of the species to handling stress and confinement. Present and future thermal safety margin (by 2060) for larvae in the Balearic Islands are 3.6 (±0.6 SE) °C and 1.8 (±0.6 SE)°C, respectively. Future research should continue exploring alternative methods for estimating thermal limits and incorporate experimental designs with multiple stressors such as exposing well- and poorly-fed larvae to heatwaves and/or different light levels.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"136 ","pages":"Article 104410"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146202013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reactive oxygen species mediated-photo-sono-ablation of melanoma cells using a novel nanocomposite of platinum-polypyrrole as a nanozyme","authors":"H. Haghighi ,&nbsp;P. Tamaddon ,&nbsp;P. Faghani-Eskandarkolaei ,&nbsp;H. Heli ,&nbsp;M. Haghani ,&nbsp;N. Sattarahmady","doi":"10.1016/j.jtherbio.2026.104428","DOIUrl":"10.1016/j.jtherbio.2026.104428","url":null,"abstract":"<div><div>Tumor eradication in non-invasive photothermal (PTT) and sonodynamic therapy (SDT) approaches is favorable in melanoma cancer. However, finding a sensitizer for synchronous PTT and SDT is a desirable request, especially if this sensitizer material has other benefits in tumor treatment. Here, a platinum (Pt)/polypyrrole nanocomposite (Pt@PPy NC) was introduced for synchronous synergistic PTT and SDT of melanoma cancer cells. To compare and clarify the effect of the nanocomposite components, platinum nanoparticles (NPs) and polypyrrole (PPy) NPs were also synthesized and evaluated. Pt@PPy NC consisted of near-spherical Pt NPs adhered by a network of PPy. Pt NPs, PPy NPs, and Pt@PPy NC had mean diameters of 13 ± 7, 177 ± 48, and 16.5 ± 2.5 nm, respectively. The results of cytotoxicity assessment of B16-F10 cells treated with Pt@PPy NC revealed that while it was cytocompatible, it represented enhanced photothermal and sonodynamic cytotoxicity (with a deeper cytotoxicity effect, compared to Pt NPs and PPy NPs). Cell viability assessments revealed that the cell killing ability was attained in a synergistic manner from the effects of Pt@PPy NC, 808-nm light, and ultrasound waves. Detection of intracellular reactive oxygen species (ROS) production revealed that the effect of PTT and SDT using Pt@PPy NC arose from induction of oxidative stress. Pt@PPy NC also represented catalase-mimicking activity and could be considered for combination therapy.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"136 ","pages":"Article 104428"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146258594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesizing evidence to beat the heat: a guideline for thermal tolerance reporting","authors":"Helena S. Bayat ,&nbsp;Sebastian Prati ,&nbsp;Ralf B. Schäfer","doi":"10.1016/j.jtherbio.2026.104432","DOIUrl":"10.1016/j.jtherbio.2026.104432","url":null,"abstract":"<div><div>Despite widespread popularity throughout the last century, thermal tolerance methods lack a standardized reporting format. A standardized reporting format streamlines the compilation, synthesis, and analysis of physiological measures of thermal tolerance across the literature, enabling large-scale analyses. These analyses are increasingly valuable in the context of accelerating global warming, as they provide the statistical power to address questions on the determinants and implications of thermal tolerance at scale. We fill this gap by providing a brief history of methods used to determine thermal tolerance, describing variables pertinent to each method, and proposing a reporting format for variables associated with each method.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"136 ","pages":"Article 104432"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146776385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiple stressors, including cold exposure, disrupt growth and intestinal homeostasis via TLR4/p38MAPK/NF-κB and AMPK/SIRT1/PGC-1α pathways in layer chicks","authors":"Qingqing Chang ,&nbsp;Haiyue Gong ,&nbsp;Liying Pan ,&nbsp;Zhaohong Pu ,&nbsp;Jiaqi Zhang ,&nbsp;Jianhong Li ,&nbsp;Jun Bao ,&nbsp;Runxiang Zhang","doi":"10.1016/j.jtherbio.2026.104431","DOIUrl":"10.1016/j.jtherbio.2026.104431","url":null,"abstract":"<div><div>Chronic and multifactorial stressors, including low-temperature exposure, represent major challenges in modern poultry systems. This study evaluated the effects of a chronic unpredictable mild stress (CUMS) model on growth performance and intestinal homeostasis in layer chicks. A total of 300 one-day-old chicks were randomly assigned to either a control (CON) group or CUMS group for a 5-week trial. CUMS significantly reduced body weight (BW) and feed intake (ADFI) while increasing the feed conversion ratio (F/G) (<em>P</em> &lt; 0.05). Serum biochemical alterations indicated disrupted protein and lipid metabolism and elevated liver enzyme activity. CUMS markedly increased serum diamine oxidase (DAO) and D-lactic acid (D-LA) levels (<em>P</em> &lt; 0.05). Histological, ultrastructural and immunofluorescence analyses showed villus damage, reduced goblet cells, disrupted tight-junction proteins, and notable mitochondrial abnormalities, including swollen mitochondria, loss of cristae integrity, and increased ROS accumulation; ATP concentrations were significantly reduced across intestinal segments (<em>P</em> &lt; 0.05). Mechanistically, CUMS suppressed humoral immunity and activated TLR4/p38MAPK/NF-κB signaling with increased pro-inflammatory and decreased anti-inflammatory cytokines (<em>P</em> &lt; 0.05). Oxidative stress was evidenced by increased malondialdehyde (MDA) and reduced antioxidant enzyme activities (<em>P</em> &lt; 0.05), alongside inhibition of the Nrf2/HO-1 pathway. Apoptosis was enhanced via mitochondrial and death receptor pathways, with reduced Bcl-2/Bax ratios and elevated cleaved Caspase-3 (<em>P</em> &lt; 0.05). Additionally, the AMPK/SIRT1/PGC-1α pathway and mitochondrial biogenesis-related genes were significantly suppressed (<em>P</em> &lt; 0.05). Overall, multi-stressor CUMS model compromises intestinal homeostasis and growth through convergent inflammatory, oxidative, apoptotic, and mitochondrial mechanisms.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"136 ","pages":"Article 104431"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147271352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neutrophil:lymphocyte ratio and cell-free DNA dynamics during excessive heat stress in occupational and experimental settings","authors":"Erik Hansson ,&nbsp;Rachel E. Gilworth ,&nbsp;Jason R. Glaser ,&nbsp;Denis Chavarría ,&nbsp;Bethany D. Skinner ,&nbsp;Ilana Weiss ,&nbsp;Richard J. Johnson ,&nbsp;Magdalena Madero ,&nbsp;Mårten Segelmark ,&nbsp;David H. Wegman ,&nbsp;Catharina Wesseling ,&nbsp;Kristina Jakobsson ,&nbsp;Rebekah A.I. Lucas","doi":"10.1016/j.jtherbio.2026.104424","DOIUrl":"10.1016/j.jtherbio.2026.104424","url":null,"abstract":"<div><h3>Introduction</h3><div>Systemic inflammation is postulated to mediate heat stroke and heat-related organ injury, yet acute inflammatory responses among heat-stressed workers remains poorly understood. We aimed to describe neutrophil mobilisation and potential release of DNA during heat stress in multiple hot occupational settings and a controlled experimental setting.</div></div><div><h3>Methods</h3><div>Neutrophil:lymphocyte ratio (NLR) was investigated in six sugarcane worker groups: Nicaraguan cohorts consisting of 1a) workers undergoing pre-employment screening (N = 5257), 1b) workers with acute kidney injury (AKI, N = 470); 2) Salvadoran cane cutters (N = 45) sampled pre/post-shift before and during a rest-shade-hydration intervention; 3) Mexican cane workers performing 3a) heavy (N = 148) and 3b) light-moderate (N = 24) work, sampled pre/post shift; and 4) Honduran cane cutters sampled pre/post-shift (N = 72). Cell-free DNA (cf-DNA) was measured in two cross-shift sugarcane worker groups (N = 26, El Salvador and N = 20, Nicaragua). NLR and cf-DNA was also measured in research participants (N = 10) exercising in temperate and hot conditions.</div></div><div><h3>Results</h3><div>NLR was elevated in sugarcane workers with AKI and increased during work shifts. Large positive NLR changes were associated with not having rest-shade-hydration, heavy workload, high environmental heat and high core body temperatures. cf-DNA increased across work-shifts in both cane cutter groups and after exercise in heat.</div></div><div><h3>Conclusion</h3><div>Neutrophil mobilisation was common among workers with AKI, and NLR and cf-DNA increased during and after field-based occupational and experimental heat stress. The findings indicate that acute systemic inflammation with neutrophil activation and destruction is common during excessive exertional heat stress.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"136 ","pages":"Article 104424"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147284271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Migration phenology of adult Chinook salmon: tradeoffs among acute and cumulative thermal exposure risks","authors":"Matthew L. Keefer,&nbsp;Christopher C. Caudill","doi":"10.1016/j.jtherbio.2026.104388","DOIUrl":"10.1016/j.jtherbio.2026.104388","url":null,"abstract":"<div><div>Migratory coldwater species like anadromous salmonids are highly sensitive to river temperatures and methods are needed for estimating their exposure and risk. We built an agent-based model (ABM) for a threatened spring-run Chinook salmon population over 220-km of their adult migration in Oregon’s Willamette and North Santiam River basins. Upstream movement rules for the ABM were derived from a companion study of 161 radio-tagged salmon that moved through five study reaches before reaching prespawn holding sites. Tagged fish moved faster when river temperatures were warmer in all reaches, informing movement rules. We used the ABM to simulate continuous thermal histories for salmon migrating in two years (2011, 2015) with sharply contrasting thermal regimes and used the simulations to address hypotheses about thermal exposure and prespawn mortality risks. In both cool (2011) and warm (2015) years, early-run salmon had high cumulative exposure, whereas late-run salmon encountered acutely high temperatures, indicating substantive risk trade-offs within annual runs. On average, total degree day (DD) accumulations during migration and holding were ∼1100 (2011) and ∼1500 DD (2015), with 56 % and 69 %, respectively, accruing during holding in the terminal reach. Approximately 3 % (2011) and 24 % (2015) of simulated salmon encountered temperature maxima ≥21 °C, a threshold with known behavioral and physiological impacts. Estimates of prespawn mortality from an independent carcass dataset were ∼29 % (2011) and ∼61 % (2015), but it is unknown whether cumulative or acute processes (or both) precipitated the mortality. ABMs can help fisheries managers quantify environmental exposure, identify risks, and develop temperature mitigation strategies.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"136 ","pages":"Article 104388"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"RSK2 facilitates beige fat formation through thermogenic and glycolytic pathways","authors":"Yan Cai ,&nbsp;Jun-jun Chen ,&nbsp;Lin-fei He ,&nbsp;Yao Xu ,&nbsp;Rui-qi Yang ,&nbsp;Zhi-chun Yang","doi":"10.1016/j.jtherbio.2026.104389","DOIUrl":"10.1016/j.jtherbio.2026.104389","url":null,"abstract":"<div><h3>Objectives</h3><div>Beige adipose tissue offers therapeutic potential for metabolic disorders. Notably, glycolytic beige adipocytes, which can be activated independently of β-adrenergic signaling, may provide unique advantages. This study aimed to investigate the role of p90 ribosomal S6 kinase-2 (RSK2) in both cold-induced and cold-independent glycolytic beige adipocyte formation.</div></div><div><h3>Methods</h3><div>We employed C57BL/6J mice subjected to cold exposure (4 °C) or high-fat diet (HFD) and analyzed adipose tissue for thermogenic and glycolytic markers. In vitro, subcutaneous adipose-derived stem cells (primary preadipocytes) were cultured at 28 °C to mimic cold exposure. RSK2 expression was manipulated via knockdown or overexpression to evaluate its functional role.</div></div><div><h3>Results</h3><div>Cold exposure upregulated uncoupling protein-1 (UCP1) and RSK2 in vivo, while HFD suppressed RSK2, UCP1, enolase 1 (ENO1), and pyruvate kinase isoform M2 (PKM2). In primary preadipocytes, cold exposure induced UCP1 and RSK2 expression and reduced triglyceride accumulation. RSK2 knockdown suppressed UCP1, acetyl-CoA carboxylase (ACC), and hormone-sensitive lipase (HSL) but increased carnitine palmitoyl transferase expression. It also reduced PKM2, ENO1, and lactate production under normothermic conditions, whereas RSK2 overexpression had opposite effects. High-glucose and high-insulin treatment decreased RSK2, glycolytic and thermogenic markers, and insulin signaling, which were reversed by RSK2 overexpression. <strong>Conclusions</strong>: RSK2 plays a dual role in mediating cold-induced and cold-independent glycolytic beige adipocyte formation. It may serve as a promising target for treating obesity and related metabolic disorders.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"136 ","pages":"Article 104389"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sex-dependent calcium dynamics in mouse skeletal muscle: Responses to cooling and caffeine","authors":"Kosei Hayakawa ,&nbsp;Ryo Takagi ,&nbsp;Ayaka Tabuchi ,&nbsp;Haruka Ugawa ,&nbsp;Daiki Watanabe ,&nbsp;Daisuke Hoshino ,&nbsp;David C. Poole ,&nbsp;Yutaka Kano","doi":"10.1016/j.jtherbio.2026.104412","DOIUrl":"10.1016/j.jtherbio.2026.104412","url":null,"abstract":"<div><div>Intracellular calcium ion concentration ([Ca²⁺]i) regulation in skeletal muscle may vary with sex and muscle fiber type, but the precise nature of its response to temperature changes and pharmacological caffeine stimulation is not fully understood. This study aimed to elucidate sex-dependent and muscle fiber type-specific characteristics of muscle cooling, caffeine stimulation, and their combined effects. We investigated the effects of cooling (30 °C to 0 °C) and caffeine stimulation (1.25–80 mM) separately and in combination (cooling + 1.25 mM caffeine) in fast-twitch (plantaris, PLA) and slow-twitch (soleus, SOL) muscles of male and female C57BL/6J mice. [Ca²⁺]i dynamics were analyzed using <em>in vivo</em> Fura-2 bioimaging under isoflurane anesthesia. The temperature threshold for the onset of [Ca²⁺]i accumulation was significantly higher in SOL than in PLA, with no significant difference between sexes (males: PLA 2.3 ± 0.9 °C, SOL 4.5 ± 2.2 °C; females: PLA 2.3 ± 0.8 °C, SOL 4.3 ± 1.3 °C). Conversely, the [Ca²⁺]i response to caffeine was significantly higher in females than in males at high concentrations (80 mM). Furthermore, the combined stimulation of cooling and caffeine had a greater effect on females than on males. Our findings also indicate that the phosphorylation response of ryanodine receptors to caffeine was significantly higher in females than in males. In conclusion, while no sex differences were observed in the [Ca²⁺]i response to cooling, clear sex-dependent differences (males &lt; females) were observed in the response to caffeine.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"136 ","pages":"Article 104412"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146170257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}