{"title":"Resistance training-induced dihydrotestosterone is blunted in aging rat skeletal muscle.","authors":"Yung-Li Hung, Akihito Ishigami, Shuichi Machida","doi":"10.1016/j.jphyss.2025.100019","DOIUrl":"10.1016/j.jphyss.2025.100019","url":null,"abstract":"<p><p>This study aimed to investigate the influence of aging on steroid hormone production in skeletal muscles in response to resistance training. Male F344 rats, aged 4 months (young) and 22 months (old), were randomized into the sedentary and training groups. The training group performed resistance training by climbing a ladder with a load every three days for eight weeks. After the training period, the flexor hallucis longus muscle was dissection, and muscle steroid hormone levels were analyzed using liquid chromatography-tandem mass spectrometry. We found that resistance training significantly increased muscle mass in young and old rats, although the increase was less pronounced in the latter. In young, trained rats, muscle dihydrotestosterone levels were approximately 35-fold higher compared to sedentary controls (p < 0.01); dihydrotestosterone levels did not differ significantly between sedentary and trained old rats. These findings indicate that resistance training-induced dihydrotestosterone production is blunted in aging rat skeletal muscle.</p>","PeriodicalId":16832,"journal":{"name":"Journal of Physiological Sciences","volume":"75 2","pages":"100019"},"PeriodicalIF":2.6,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12002648/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143788358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Masao Kakoki, John R Hagaman, Masahiko Terajima, Masako Nagasawa, Katsumi Uoshima, Mitsuo Yamauchi, Oliver Smithies, Kenji Kansaku
{"title":"Proximal aortic aneurysms in mice underexpressing transforming growth factor-β1.","authors":"Masao Kakoki, John R Hagaman, Masahiko Terajima, Masako Nagasawa, Katsumi Uoshima, Mitsuo Yamauchi, Oliver Smithies, Kenji Kansaku","doi":"10.1016/j.jphyss.2025.100024","DOIUrl":"10.1016/j.jphyss.2025.100024","url":null,"abstract":"<p><p>In humans, loss-of-function mutations in multiple component genes of transforming growth factor (TGF)-β signaling have been demonstrated to cause proximal aortic aneurysms. However, association of human variants in the prototype ligand TGFB1 with thoracic aortic aneurysms have not been reported to date. To delineate the consequences of genetically altered Tgfb1 expression on aortic phenotype in mammals, we studied aortic phenotype in mice with loss-of-functions or gain-of-function mutations in Tgfb1 (Tgfb1<sup>L/L</sup> and Tgfb1<sup>H/H</sup>). Tgfb1<sup>L/L</sup> mice spontaneously developed proximal aortic aneurysms and had markedly shortened lifespans as compared with wildtype, whereas Tgfb1<sup>H/H</sup>mice did not develop aortic aneurysms and had comparable lifespans with wildtype. Aortic levels of collagen and elastin stable crosslinks, and the expression of their associated enzymes in Tgfb1<sup>L/L</sup> mice were significantly less than those in wildtype. These results suggest that TGF-β1 is protective against aortic aneurysms at least partly via increasing the cross-linking of collagen and elastin.</p>","PeriodicalId":16832,"journal":{"name":"Journal of Physiological Sciences","volume":"75 2","pages":"100024"},"PeriodicalIF":3.2,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12162004/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144199447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"TRPV1 and thermosensitivity.","authors":"Makoto Tominaga, Moe Iwata","doi":"10.1016/j.jphyss.2025.100009","DOIUrl":"10.1016/j.jphyss.2025.100009","url":null,"abstract":"<p><p>The capsaicin receptor TRPV1 was identified as the first heat-activated ion channel in 1997. Since then, numerous studies have been performed on its physiological functions and structure-function relationship, and chemicals targeting TRPV1 have been developed. It has been more than 27 years since the initial cloning of the TRPV1 gene and more than 11 years since the clarification of its structure at the atomic level using cryo-EM. However, we still lack good chemical antagonists of TRPV1 as medicines. TRPV1 is involved in body temperature regulation, but how TRPV1 antagonists cause hyperthermia and how TRPV1 is involved in body temperature regulation are not yet clearly understood. More research is needed in the thermal biology field.</p>","PeriodicalId":16832,"journal":{"name":"Journal of Physiological Sciences","volume":"75 1","pages":"100009"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11864123/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143399416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The interaction between orexin, sleep deprivation and Alzheimer's disease: Unveiling an Emerging Connection.","authors":"Masoumeh Kourosh-Arami, Mahdi Ramezani, Alireza Komaki","doi":"10.1016/j.jphyss.2024.100004","DOIUrl":"10.1016/j.jphyss.2024.100004","url":null,"abstract":"<p><p>Alzheimer's disease (AD) is a devastating neurodegenerative disorder characterized by progressive cognitive decline and memory loss. Sleep-wake disorders are an extremely predominant and often disabling aspect of AD. Ox is vital in maintaining the sleep-wake cycle and promoting wakefulness. Dysfunction of Ox signaling has been associated with sleep disorders such as narcolepsy. In AD patients, the increase in cerebrospinal fluid Ox levels is related to parallel sleep deterioration. The relationship between AD and sleep disturbances has gained increasing attention due to their potential bidirectional influence. Disruptions in sleep patterns are commonly observed in AD patients, leading researchers to investigate the possible involvement of Ox in sleep disturbances characteristic of the disease. This review article explores the role of the Ox system in AD, and the intricate relationship between AD and sleep, highlighting the potential mechanisms, impact on disease pathology, and therapeutic interventions to improve sleep quality in affected individuals.</p>","PeriodicalId":16832,"journal":{"name":"Journal of Physiological Sciences","volume":"75 1","pages":"100004"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11979663/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"TRPV3 in skin thermosensation and temperature responses.","authors":"Jing Lei, Makoto Tominaga","doi":"10.1016/j.jphyss.2025.100005","DOIUrl":"10.1016/j.jphyss.2025.100005","url":null,"abstract":"<p><p>Human skin, as a sophisticated sensory organ, is able to detect subtle changes in ambient temperature. This thermosensory capability is primarily mediated by temperature-sensitive TRP channels expressed in both sensory neurons and keratinocytes. Among these, TRPV3, which responds to warm temperatures and plays a crucial role in various skin functions, is particularly notable. TRPV3 channels not only detect moderate warmth but are also sensitive to chemical ligands that evoke thermal sensations. The activation of TRPV3 by warm temperatures and compounds highlights its importance in the molecular mechanisms underlying skin thermosensation. This review mainly discusses the role of TRPV3, particularly its contribution to skin thermosensation and structural insights into its temperature sensitivity, providing an understanding of how TRPV3 modulates thermal perception at the molecular level.</p>","PeriodicalId":16832,"journal":{"name":"Journal of Physiological Sciences","volume":"75 1","pages":"100005"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11979661/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Involvement of ROS signal in aging and regulation of brain functions.","authors":"Sho Kakizawa","doi":"10.1016/j.jphyss.2024.100003","DOIUrl":"10.1016/j.jphyss.2024.100003","url":null,"abstract":"<p><p>Reactive oxygen species (ROS) are redox-signaling molecules involved in aging and lifestyle-related diseases. In the brain, in addition to the production of ROS as byproducts of metabolism, expression of ROS synthases has recently been demonstrated, suggesting possible involvement of ROS in various brain functions. This review highlights current knowledge on the relationship between ROS and brain functions, including their contribution to age-related decline in synaptic plasticity and cognitive function. While most studies demonstrate either the positive or negative effects of ROS on synaptic plasticity, the dual effects of ROS at individual synapses have been demonstrated recently in the mouse cerebellum. Furthermore, the cooperative interaction between these two effects determines the direction of synaptic plasticity. It is anticipated that further elucidation of both the positive and negative effects of ROS on brain function will lead to the development of more effective therapeutic strategies with fewer side effects for ROS-related brain dysfunction.</p>","PeriodicalId":16832,"journal":{"name":"Journal of Physiological Sciences","volume":"75 1","pages":"100003"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11979664/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Circadian sleep-wake rhythm reversal in mice implanted with stomach cancer cell lines.","authors":"Motohide Goto, Takashi Maruyama, Miki Nonaka, Yasuhito Uezono, Yoichi Ueta, Susumu Ueno","doi":"10.1016/j.jphyss.2025.100007","DOIUrl":"10.1016/j.jphyss.2025.100007","url":null,"abstract":"<p><p>The present study explored the phenotype and behavioral characteristics of mice implanted with the 85As2 human stomach cancer cell lines. Generally, mice are nocturnal; they are active during the dark phase and resting in the light phase. However, mice implanted with 85As2 cells demonstrated diurnal patterns, showing activity in the light phase. The similar light-dark behavioral reversal was noted in mice implanted with other cancer cell lines, such as the HCT116 human colon cancer cell lines. Furthermore, 85As2 implanted mice revealed significant shortening of the free-running period under constant dark conditions. To explore the underlying physiological mechanisms of this circadian rhythm reversal, diurnal variations in the suprachiasmatic nucleus (SCN) were analyzed with observation of c-Fos expression. Interestingly, no significant difference was found in the SCN activity between the control and 85As2-implanted mice, demonstrating rhythm reversal. It is suggested that the lesion causing this rhythm reversal exists downstream of the SCN.</p>","PeriodicalId":16832,"journal":{"name":"Journal of Physiological Sciences","volume":"75 1","pages":"100007"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11864213/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143408639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The difference in arterial baroreflex sensitivity between the supine and standing positions in healthy subjects.","authors":"Teruhiko Sakamoto, Satoshi Mitsuyama, Toru Nagasawa, Kazuomi Kario, Seiji Ozawa","doi":"10.1016/j.jphyss.2025.100006","DOIUrl":"10.1016/j.jphyss.2025.100006","url":null,"abstract":"<p><p>The spectral analysis of heart rate variability (HRV) has long been considered a practical, noninvasive tool to assess autonomic nervous functions that regulate the cardiovascular system. The conventional method, however, has limitations in characterizing transient changes of HRV. We have overcome this problem by adopting the time-frequency analysis method. Using this method, we attempted to clarify differences in the arterial baroreflex (ABR) activity during a transient change in the heart rate between the supine and standing positions in healthy subjects. We found that the ABR gain was significantly greater in the supine position compared to standing, and this gain increase was due to transient increases in 0.15 to 0.20 Hz components of HRV spectral powers caused by enhanced cardiac vagal outflow. Based on these findings, we conclude that the orthostatic stress induced by the postural change from supine to standing markedly reduces the baroreflex gain by suppressing high-frequency cardiac vagal outflow.</p>","PeriodicalId":16832,"journal":{"name":"Journal of Physiological Sciences","volume":"75 1","pages":"100006"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11979646/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143374259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Eicosapentaenoic acid prevents atrial electrocardiographic impairments and atrial fibrillation in high fat diet mice.","authors":"Kosuke Horii, Katsushige Ono, Tomoko Sumi, Mayo Higashihara, Nobuhiro Zaima, Seiji Masuda, Masaki Morishima","doi":"10.1016/j.jphyss.2025.100014","DOIUrl":"10.1016/j.jphyss.2025.100014","url":null,"abstract":"<p><p>There is growing evidence that eicosapentaenoic acid (EPA) uptake has beneficial effects on various cardiovascular diseases. However, electrophysiological actions of EPA remain poorly documented. To investigate the potential antiarrhythmic effects of EPA, mice were fed a high-fat diet (HFD) or an HFD supplemented with EPA for eight weeks. Electrocardiogram (ECG) recordings in combined with esophageal electrical stimulation revealed that HFD-fed mice exhibited bradycardia, reduced P-wave amplitude, and prolonged P-wave duration. Atrial fibrillation (AF) was induced in 100 % of HFD mice, which was only in 50 % of EPA-supplemented mice with significantly shorter durations. HFD-fed mice showed decreased expression of Cav1.2-mRNA, increased expression of Kv1.5-mRNA, elevated expression of inflammatory cytokines (IL-1β, TNF-α, and IL-10), and larger fibrotic area in atrial tissue, which were all reversed by EPA supplementation. These findings suggest that long-term dietary intake of EPA may help maintain normal atrial function and structure, thereby reducing the risk of AF.</p>","PeriodicalId":16832,"journal":{"name":"Journal of Physiological Sciences","volume":"75 1","pages":"100014"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11953981/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Rebastinib inhibits FoxO1 activity and reduces dexamethasone-induced atrophy and its-related gene expression in cultured myotubes.","authors":"Tomoki Sato, Akihito Morita, Yui Watanabe, Yumi Naito, Haruka Kawaji, Takumi Nakagawa, Hiroki Hamaguchi, Yasuko Manabe, Nobuharu L Fujii, Naohisa Ogo, Akira Asai, Yasutomi Kamei, Shinji Miura","doi":"10.1016/j.jphyss.2025.100012","DOIUrl":"10.1016/j.jphyss.2025.100012","url":null,"abstract":"<p><p>FoxO1, a transcription factor, is upregulated in skeletal muscle during atrophy and inactivation of FoxO1 is a potential strategy to prevent muscle loss. This study identified Rebastinib as a potent suppressor of FoxO1 activity among protein kinase inhibitors. To determine whether Rebastinib inhibits atrophy-related ubiquitin ligases gene expression and mitigates atrophy in mouse skeletal muscle-derived cells, we investigated its protective effects of the compound against dexamethasone (DEX)-induced muscle atrophy using C2C12 myotubes. Rebastinib inhibited the DEX-induced upregulation of atrogin-1 and MuRF-1 mRNA, and atrogin-1 protein. Rebastinib also suppressed protein degradation and increased myotube diameter in DEX-treated C2C12 myotubes. Additionally, Rebastinib ameliorated the DEX- and cachexia-induced reduction in contractile force generation. Although the precise mechanisms underlying the action of Rebastinib against muscle atrophy and its efficacy in vivo remains to be elucidated, this compound shows great potential as a therapeutic agent for muscle atrophy.</p>","PeriodicalId":16832,"journal":{"name":"Journal of Physiological Sciences","volume":"75 1","pages":"100012"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11905838/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143476057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}