Journal of Physiology-London最新文献

筛选
英文 中文
The place around me is (not) understood: Musings of an active single neurone. 我周围的地方是(不)被理解的:一个活跃的单个神经元的沉思。
IF 4.7 2区 医学
Journal of Physiology-London Pub Date : 2025-01-21 DOI: 10.1113/JP287796
Oscar Sacchi
{"title":"The place around me is (not) understood: Musings of an active single neurone.","authors":"Oscar Sacchi","doi":"10.1113/JP287796","DOIUrl":"https://doi.org/10.1113/JP287796","url":null,"abstract":"","PeriodicalId":50088,"journal":{"name":"Journal of Physiology-London","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143015224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Effects of patent foramen ovale in migraine: a metabolomics-based study. 卵圆孔未闭对偏头痛的影响:一项基于代谢组学的研究。
IF 4.7 2区 医学
Journal of Physiology-London Pub Date : 2025-01-21 DOI: 10.1113/JP286772
Bosi Dong, Xin Li, Lu Zhang, Ge Liang, Wen Zheng, Luolan Gui, Shuming Ji, Yusha Tang, Hua Li, Wanling Li, Ruiqi Yang, Yajiao Li, Anjiao Peng, Yucheng Chen, Meng Gong, Lei Chen
{"title":"Effects of patent foramen ovale in migraine: a metabolomics-based study.","authors":"Bosi Dong, Xin Li, Lu Zhang, Ge Liang, Wen Zheng, Luolan Gui, Shuming Ji, Yusha Tang, Hua Li, Wanling Li, Ruiqi Yang, Yajiao Li, Anjiao Peng, Yucheng Chen, Meng Gong, Lei Chen","doi":"10.1113/JP286772","DOIUrl":"https://doi.org/10.1113/JP286772","url":null,"abstract":"<p><p>Patent foramen ovale (PFO), a cardiac anatomical anomaly inducing abnormal haemodynamics, leads to a paradoxical bypass of the pulmonary circulation. PFO closure might alleviate migraines; however, clinical evidence and basic experiments for the relationship are lacking. To explore the effect of PFO on migraine, 371 migraineurs finishing blood tests and contrast transthoracic echocardiography for the detection of PFO were prospectively included. Multivariate regression analysis revealed that PFO was independently associated with aura, and lower cystatin-C (cys-C) and calcium levels. Among them, patients with PFO who underwent percutaneous PFO closure were continuously followed up 1 year after the operation. The intensity of migraine was significantly relieved and the levels of cys-C and calcium increased after PFO closure. Untargeted and targeted metabolomics of plasma from migraineurs before and after PFO closure revealed that 5-HT and glutathione (GSH) metabolites were differentially expressed after PFO closure. The differential metabolites were then validated in the plasma and brain tissues of PFO mouse models by LC-MS/MS analysis. Desorption electrospray ionization mass imaging demonstrated that these metabolic alterations occurred mainly in the posterior cerebral cortex. Collectively, aura, cys-C and calcium could be biomarkers of migraineurs with PFO. PFO might have an impact on the posterior head associated with the regulation of 5-HT and GSH. PFO closure might relieve migraine by improving 5-HT clearance metabolism and ameliorating redox reactions. Our results may provide evidence for an indication of PFO closure in migraine and support the related potential mechanism. KEY POINTS: Aura, and levels of cystatin-C and calcium are biomarkers of migraineurs with a patent foramen ovale (PFO). The clearance of pulmonary metabolism of 5-HT and deoxygenated blood might be the reason for the improvement of migraine symptoms in patients with PFO. The posterior region of the brain is the main area responsible for PFO-induced migraine.</p>","PeriodicalId":50088,"journal":{"name":"Journal of Physiology-London","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143015207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The physiology of stroke neurorehabilitation 中风神经康复的生理学。
IF 4.7 2区 医学
Journal of Physiology-London Pub Date : 2025-01-21 DOI: 10.1113/JP287848
Richard G. Carson
{"title":"The physiology of stroke neurorehabilitation","authors":"Richard G. Carson","doi":"10.1113/JP287848","DOIUrl":"10.1113/JP287848","url":null,"abstract":"&lt;p&gt;The Cochrane network, in its definition of rehabilitation, refers to “interventions targeting a person's” capacity (by addressing body structures, functions, and activities/participation) … with the goal of “optimizing” the “functioning” … of “persons with health conditions currently experiencing disability or likely to experience disability …” (Negrini et al., &lt;span&gt;2022&lt;/span&gt;). In respect of the significance accorded to ‘capacity’ and ‘functioning’, rehabilitation lies squarely within the purview of physiology, with its emphasis on the integration of molecular, cellular, systems and whole-body function. Neurorehabilitation (a.k.a. neurological rehabilitation) deals more specifically (e.g. National Institute for Health &amp; Care Excellence, &lt;span&gt;2021&lt;/span&gt;) with neurological impairments that arise from injury to the brain, spine or peripheral nerves, caused by disease, trauma, tumours, infections, metabolic insults and disorders of the blood supply – such as stroke. In terms of its ramifications, stroke ranks as the second highest cause of death (Roth et al., &lt;span&gt;2018&lt;/span&gt;), and follows only neonatal disorders and ischaemic heart disease as an agent of long-term disability (Kyu et al., &lt;span&gt;2018&lt;/span&gt;). Most notably, stroke has a disability impact – in terms of severity, greater than any other chronic disease (e.g. Adamson et al., &lt;span&gt;2004&lt;/span&gt;). It is estimated that approximately 15 million strokes occur worldwide every year (World Health Organization, &lt;span&gt;2024&lt;/span&gt;). Of those who survive, half will be left with a disability that demands neurorehabilitation. With the lethality of stroke falling, and the incidence of stroke rising – especially in low-income and middle-income countries (Prust et al., &lt;span&gt;2024&lt;/span&gt;), there is a renewed imperative to direct research towards life after stroke, particularly since targets for neurorehabilitation feature prominently among the priorities identified by stroke survivors and their carers (Pollock et al., &lt;span&gt;2012&lt;/span&gt;).&lt;/p&gt;&lt;p&gt;It seems self-evident that physiological knowledge should inform stroke neurorehabilitation, particularly when there is an aspiration to increase the efficacy and efficiency of its delivery. In this context, such knowledge might extend to mechanisms that mediate adaptation to, or recovery from, brain damage. It may also encompass means through which a neurorehabilitation technique exerts an effect. Writing in this collection, Carson and Hayward (&lt;span&gt;2025&lt;/span&gt;) point out that these strands of knowledge are integrated less frequently than one might suppose. In addition, and unlike in many other areas of clinical science, knowledge of the relevant physiology is frequently sought (if at all) following the concoction of a novel neurorehabilitation therapy, rather than as a precursor. Perhaps this is due to lack of appreciation of an existing corpus of physiological knowledge that is directly relevant to stroke neurorehabilitation. This special issue of &lt;i&gt;T","PeriodicalId":50088,"journal":{"name":"Journal of Physiology-London","volume":"603 3","pages":"611-615"},"PeriodicalIF":4.7,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1113/JP287848","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143015223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Does exercise truly affect brain-wide glucose metabolism? 运动真的会影响全脑葡萄糖代谢吗?
IF 4.7 2区 医学
Journal of Physiology-London Pub Date : 2025-01-20 DOI: 10.1113/JP288329
Laust Vind Knudsen, Tanja Maria Michel, Abigail Jane Sheldrick-Michel, Manouchehr Seyedi Vafaee
{"title":"Does exercise truly affect brain-wide glucose metabolism?","authors":"Laust Vind Knudsen, Tanja Maria Michel, Abigail Jane Sheldrick-Michel, Manouchehr Seyedi Vafaee","doi":"10.1113/JP288329","DOIUrl":"https://doi.org/10.1113/JP288329","url":null,"abstract":"","PeriodicalId":50088,"journal":{"name":"Journal of Physiology-London","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143015206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Inhibition of diacylglycerol lipase α induced blood-brain barrier breach in female Sprague-Dawley rats. 抑制二酰基甘油脂肪酶α诱导雌性Sprague-Dawley大鼠血脑屏障破裂。
IF 4.7 2区 医学
Journal of Physiology-London Pub Date : 2025-01-19 DOI: 10.1113/JP287680
Erika Liktor-Busa, Aidan A Levine, Sally J Young, Colin Bader, Seph M Palomino, Felipe D Polk, Sarah A Couture, Paulo W Pires, Trent Anderson, Tally M Largent-Milnes
{"title":"Inhibition of diacylglycerol lipase α induced blood-brain barrier breach in female Sprague-Dawley rats.","authors":"Erika Liktor-Busa, Aidan A Levine, Sally J Young, Colin Bader, Seph M Palomino, Felipe D Polk, Sarah A Couture, Paulo W Pires, Trent Anderson, Tally M Largent-Milnes","doi":"10.1113/JP287680","DOIUrl":"https://doi.org/10.1113/JP287680","url":null,"abstract":"<p><p>The endocannabinoid system's significance in maintaining blood-brain barrier (BBB) integrity under physiological and pathological conditions is suggested by several reports, but the underlying molecular mechanisms are not well understood. In this paper, we investigated the effects of depletion of 2-arachidonoylglycerol (2-AG), one of the main endocannabinoids in the central nervous system, on BBB integrity using pharmacological tools. Female Sprague-Dawley rats were injected with the diacylglycerol lipase α (DAGLα) inhibitor LEI-106 (40 mg/kg, i.p.), followed by assessment of BBB integrity via in situ brain perfusion. Liquid chromatography-mass spectrometry, western immunoblotting, light transmittance experiments and pressure myography were also used to further examine the results of DAGLα blockade on the BBB and vascular reactivity. We found that DAGLα inhibition caused BBB opening in cortical brain areas, manifesting as increased sucrose transport measured by in situ brain perfusion. This was accompanied by reduced levels of 2-AG and decreased detection of the tight junction protein zonula occludens-1 (ZO-1). The protein level in cortical areas of neuronal PAS domain protein 4 (NPAS4), encoded by an activity-dependent immediate early gene, was increased without the presence of cortical spreading depression after LEI-106 administration. We also observed a significant increase in pressure-induced constriction within the parenchymal microcirculation after inhibition of DAGLα, possibly altering shear stress in the microcirculation. These results support the role of endogenous 2-AG in maintaining normal tight junction function. This improved understanding of the molecular mechanisms of endocannabinoid system function at the neurovascular unit can help to unlock the therapeutic potentials of cannabinoids in central nervous system disorders associated with BBB dysfunction. KEY POINTS: The administration of the diacylglycerol lipase α (DAGLα) inhibitor LEI-106 (40 mg/kg, i.p.) induced blood-brain barrier (BBB) opening of cortical brain areas in female Sprague-Dawley rats. This BBB disruption was accompanied by reduced levels of 2-arachidonoylglycerol (2-AG) and decreased detection of the tight junction protein zonula occludens-1 (ZO-1). The protein level in cortical areas of neuronal PAS domain protein 4 (NPAS4), encoded by an activity-dependent immediate early gene, was increased without the presence of cortical spreading depression after LEI-106 administration. A significant increase in pressure-induced constriction within the parenchymal microcirculation was also observed after inhibition of DAGLα, possibly altering shear stress. These results support the role of endogenous 2-AG in maintaining normal tight junction function.</p>","PeriodicalId":50088,"journal":{"name":"Journal of Physiology-London","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2025-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143015209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Cortical coding of gustatory and thermal signals in active licking mice. 活跃舔食小鼠的味觉和热信号的皮质编码。
IF 4.7 2区 医学
Journal of Physiology-London Pub Date : 2025-01-19 DOI: 10.1113/JP287499
Audrey N Nash, Morgan Shakeshaft, Cecilia G Bouaichi, Katherine E Odegaard, Tom Needham, Martin Bauer, Richard Bertram, Roberto Vincis
{"title":"Cortical coding of gustatory and thermal signals in active licking mice.","authors":"Audrey N Nash, Morgan Shakeshaft, Cecilia G Bouaichi, Katherine E Odegaard, Tom Needham, Martin Bauer, Richard Bertram, Roberto Vincis","doi":"10.1113/JP287499","DOIUrl":"10.1113/JP287499","url":null,"abstract":"<p><p>Eating behaviours are influenced by the integration of gustatory, olfactory and somatosensory signals, which all contribute to the perception of flavour. Although extensive research has explored the neural correlates of taste in the gustatory cortex (GC), less is known about its role in encoding thermal information. This study investigates the encoding of oral thermal and chemosensory signals by GC neurons compared to the oral somatosensory cortex. In this study we recorded the spiking activity of more than 900 GC neurons and 500 neurons from the oral somatosensory cortex in mice allowed to freely lick small drops of gustatory stimuli or deionized water at varying non-nociceptive temperatures. We then developed and used a Bayesian-based analysis technique to assess neural classification scores based on spike rate and phase timing within the lick cycle. Our results indicate that GC neurons rely predominantly on rate information, although phase information is needed to achieve maximum accuracy, to effectively encode both chemosensory and thermosensory signals. GC neurons can effectively differentiate between thermal stimuli, excelling in distinguishing both large contrasts (14 vs. 36°C) and, although less effectively, more subtle temperature differences. Finally a direct comparison of the decoding accuracy of thermosensory signals between the two cortices reveals that whereas the somatosensory cortex exhibited higher overall accuracy, the GC still encodes significant thermosensory information. These findings highlight the GC's dual role in processing taste and temperature, emphasizing the importance of considering temperature in future studies of taste processing. KEY POINTS: Flavour perception relies on gustatory, olfactory and somatosensory integration, with the gustatory cortex (GC) central to taste processing. GC neurons also respond to temperature, but the specifics of how the GC processes taste and oral thermal stimuli remain unclear. The focus of this study is on the role of GC neurons in the encoding of oral thermal information, particularly compared to the coding functions of the oral somatosensory cortex. We found that whereas the somatosensory cortex shows a higher classification accuracy for distinguishing water temperature, the GC still encodes a substantial amount of thermosensory information. These results emphasize the importance of including temperature as a key factor in future studies of cortical taste coding.</p>","PeriodicalId":50088,"journal":{"name":"Journal of Physiology-London","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2025-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143015205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Mouse models for metabolic health research: molecular mechanism of exercise effects on health improvement through adipose tissue remodelling. 小鼠代谢健康模型研究:通过脂肪组织重塑运动对健康改善的分子机制
IF 4.7 2区 医学
Journal of Physiology-London Pub Date : 2025-01-17 DOI: 10.1113/JP285975
Hye Jin Kim, Youn Ju Kim, Je Kyung Seong
{"title":"Mouse models for metabolic health research: molecular mechanism of exercise effects on health improvement through adipose tissue remodelling.","authors":"Hye Jin Kim, Youn Ju Kim, Je Kyung Seong","doi":"10.1113/JP285975","DOIUrl":"https://doi.org/10.1113/JP285975","url":null,"abstract":"<p><p>Exercise provides health benefits to multiple metabolic tissues through complex biological pathways and interactions between organs. However, investigating these complex mechanisms in humans is still limited, making mouse models extremely useful for exploring exercise-induced changes in whole-body metabolism and health. In this review, we focus on gaining a broader understanding of the metabolic phenotypes and molecular mechanisms induced by exercise in mouse models. We first discuss the differences in adaptations induced by aerobic and resistance exercise, and compare voluntary wheel running and forced treadmill exercise, the two main methods of aerobic exercise research in mice, to show the similarities and differences between the same aerobic exercise but different methods, and their impact on experimental outcomes. The effects of exercise on metabolic phenotypes, including alleviation of obesity and metabolic disorders, and the mechanisms involved in adipose tissue remodelling and browning are explored, as well as the role of the gut microbiota in mediating the physiological responses and metabolic effects of exercise. Understanding these molecular mechanisms and methodological aspects of exercise experiments in mouse models can serve as a valuable template for the design of future basic research in exercise physiology and will provide a strong scientific evidence base for optimizing the design of exercise intervention programmes for metabolic health.</p>","PeriodicalId":50088,"journal":{"name":"Journal of Physiology-London","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143015220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Skin disease-associated GJB4 variants differentially influence connexin stability, cell viability and channel function. 皮肤疾病相关的GJB4变异对连接蛋白稳定性、细胞活力和通道功能有不同的影响。
IF 4.7 2区 医学
Journal of Physiology-London Pub Date : 2025-01-16 DOI: 10.1113/JP286367
Sergiu A Lucaciu, Stephanie E Leighton, Robert S Wong, Varun Sekar, Alexandra Hauser, Nhu-An Lai, Danielle Johnston, Peter B Stathopulos, Donglin Bai, Dale W Laird
{"title":"Skin disease-associated GJB4 variants differentially influence connexin stability, cell viability and channel function.","authors":"Sergiu A Lucaciu, Stephanie E Leighton, Robert S Wong, Varun Sekar, Alexandra Hauser, Nhu-An Lai, Danielle Johnston, Peter B Stathopulos, Donglin Bai, Dale W Laird","doi":"10.1113/JP286367","DOIUrl":"https://doi.org/10.1113/JP286367","url":null,"abstract":"<p><p>Here we characterize seven Cx30.3 gene variants (R22H, S26Y, P61R, C86S, E99K, T130M and M190L) clinically associated with the rare skin disorder erythrokeratodermia variabilis et progressiva (EKVP) in tissue-relevant and differentiation-competent rat epidermal keratinocytes (REKs). We found that all variants, when expressed alone or together with wildtype (WT) Cx30.3, had the capacity to traffic and form gap junctions with an efficiency like WT Cx30.3. Cx30.3 was found to have a slower relative turnover than Cx43. However, turnover was more rapid for the R22H and P61R variants relative to Cx30.3. Furthermore, REKs that expressed the P61R variant exhibited reduced viability and were more permeable to fluorescent dyes, indicative of leaky hemichannels and/or the loss of membrane integrity associated with cell death. In connexin-null AD-293 cells, dual patch clamp studies revealed that the variants had either reduced (C86S) or no (S26Y and T130M) gap junction channel function. The remaining variants formed functional gap junction channels with enhanced transjunctional voltage (V<sub>j</sub>)-dependent gating. Moreover, WT Cx30.3 and functional variant gap junction channels had similar unitary conductance of ∼34-42 pS, though variant channels appeared to have lower open probability than WT Cx30.3 channels at high V<sub>j</sub>s. In conclusion, EKVP-associated Cx30.3 variants each alter one or more Cx30.3 characteristics although the molecular changes identified for E99K were limited to enhanced V<sub>j</sub> gating. The breadth of molecular changes identified may all be sufficient to cause EKVP, but this remains to be firmly established as more familial patients are genotyped for these variants. KEY POINTS: Here we characterize seven Cx30.3 variants (R22H, S26Y, P61R, C86S, E99K, T130M and M190L) that have been clinically associated with the rare skin disorder erythrokeratodermia variabilis et progressiva (EKVP). We discovered human Cx30.3 undergoes relatively slow turnover compared with Cx43 and exhibits kinetically slow and limited voltage gating. Wildtype Cx30.3 and all variants localized to intracellular compartments and gap junctions in rat epidermal keratinocytes. Each EKVP-associated Cx30.3 variant altered one or more Cx30.3 characteristics related to protein stability, cell viability and/or channel function. The breadth of molecular changes identified for each Cx30.3 variant may independently be sufficient to cause EKVP, but this remains to be firmly established through additional genetic and molecular analysis.</p>","PeriodicalId":50088,"journal":{"name":"Journal of Physiology-London","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143015221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
In vivo calcium imaging reveals directional sensitivity of C-low threshold mechanoreceptors. 体内钙显像显示c -低阈机械感受器的定向敏感性。
IF 4.7 2区 医学
Journal of Physiology-London Pub Date : 2025-01-15 DOI: 10.1113/JP286631
Evangelia Semizoglou, Laure Lo Re, Steven J Middleton, Jimena Perez-Sanchez, Tommaso Tufarelli, David L Bennett, Kim I Chisholm
{"title":"In vivo calcium imaging reveals directional sensitivity of C-low threshold mechanoreceptors.","authors":"Evangelia Semizoglou, Laure Lo Re, Steven J Middleton, Jimena Perez-Sanchez, Tommaso Tufarelli, David L Bennett, Kim I Chisholm","doi":"10.1113/JP286631","DOIUrl":"https://doi.org/10.1113/JP286631","url":null,"abstract":"<p><p>C-low threshold mechanoreceptors (C-LTMRs) in animals (termed C-tactile (CT) fibres in humans) are a subgroup of C-fibre primary afferents, which innervate hairy skin and respond to low-threshold punctate indentations and brush stimuli. These afferents respond to gentle touch stimuli and are implicated in mediating pleasant/affective touch. These afferents have traditionally been studied using low-throughput, technically challenging approaches, including microneurography in humans and teased fibre electrophysiology in other mammals. Here we suggest a new approach to studying genetically labelled C-LTMRs using in vivo calcium imaging. We used an automated rotating brush stimulus and von Frey filaments, applied to the hairy skin of anaesthetized mice to mirror light and affective touch. Simultaneously we visualized changes in C-LTMR activity and confirmed that these neurons are sensitive to low-threshold punctate mechanical stimuli and brush stimuli with a strong preference for slow brushing speeds. We also reveal that C-LMTRs are directionally sensitive, showing more activity when brushed against the natural orientation of the hair. We present in vivo calcium imaging of genetically labelled C-LTMRs as a useful approach that can reveal new aspects of C-LTMR physiology. KEY POINTS: C-low threshold mechanoreceptors are sensitive to the directionality of a brush stimulus, being preferentially activated by brushing against the grain of the hair, compared with brushing with the grain of the hair. This is surprising as brushing against the grain of the hair is considered less pleasant. In vivo calcium imaging is a useful approach to the study of C-low threshold mechanoreceptors. While viral transfection, using systemic AAV9, is effective in labelling most sensory neuron populations in the dorsal root ganglion, it fails to label C-low threshold mechanoreceptors.</p>","PeriodicalId":50088,"journal":{"name":"Journal of Physiology-London","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142985260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Cognitive impairment caused by compromised hepatic ketogenesis is prevented by endurance exercise. 由肝生酮受损引起的认知障碍可通过耐力运动加以预防。
IF 4.7 2区 医学
Journal of Physiology-London Pub Date : 2025-01-14 DOI: 10.1113/JP287573
Taylor J Kelty, Nathan R Kerr, Chih H Chou, Grace E Shryack, Christopher L Taylor, Alexa A Krause, Alexandra R Knutson, Josh Bunten, Tom E Childs, Grace M Meers, Ryan J Dashek, Patrycja Puchalska, Peter A Crawford, John P Thyfault, Frank W Booth, R Scott Rector
{"title":"Cognitive impairment caused by compromised hepatic ketogenesis is prevented by endurance exercise.","authors":"Taylor J Kelty, Nathan R Kerr, Chih H Chou, Grace E Shryack, Christopher L Taylor, Alexa A Krause, Alexandra R Knutson, Josh Bunten, Tom E Childs, Grace M Meers, Ryan J Dashek, Patrycja Puchalska, Peter A Crawford, John P Thyfault, Frank W Booth, R Scott Rector","doi":"10.1113/JP287573","DOIUrl":"https://doi.org/10.1113/JP287573","url":null,"abstract":"<p><p>Extensive research has demonstrated endurance exercise to be neuroprotective. Whether these neuroprotective benefits are mediated, in part, by hepatic ketone production remains unclear. To investigate the role of hepatic ketone production on brain health during exercise, healthy 6-month-old female rats underwent viral knockdown of the rate-limiting enzyme in the liver that catalyses the first reaction in ketogenesis: 3-hydroxymethylglutaryl-CoA synthase 2 (HMGCS2). Rats were then subjected to either a bout of acute exercise or 4 weeks of chronic treadmill running (5 days/week) and cognitive behavioural testing. Acute exercise elevated ketone plasma concentration 1 h following exercise. Hepatic HMGCS2 knockdown, verified by protein expression, reduced ketone plasma concentration 1 h after acute exercise and 48 h after chronic exercise. Proteomic analysis and enrichment of the frontal cortex revealed hepatic HMGCS2 knockdown reduced markers of mitochondrial function 1 h after acute exercise. HMGCS2 knockdown significantly reduced state 3 complex I + II respiration in isolated mitochondria from the frontal cortex after chronic exercise. Spatial memory and protein markers of synaptic plasticity were significantly reduced by HMGCS2 knockdown. These deficiencies were prevented by chronic endurance exercise training. In summary, these are the first data to propose that hepatic ketogenesis is required to maintain cognition and mitochondrial function, irrespective of training status, and that endurance exercise can overcome neuropathology caused by insufficient hepatic ketogenesis. These results establish a mechanistic link between liver and brain health that enhance our understanding of how peripheral tissue metabolism influences brain health. KEY POINTS: Decades of literature demonstrate endurance exercise to be neuroprotective. Whether neuroprotective benefits are mediated, in part, by hepatic ketone production remains unclear. This study provides the first set of data that suggest hepatic ketogenesis is required to maintain cognition, synaptic plasticity and mitochondrial function. These data indicate endurance exercise can protect against cognitive decline caused by compromised hepatic ketogenesis. These results establish a mechanistic link between liver and brain function, prompting further investigation of how hepatic metabolism influences brain health.</p>","PeriodicalId":50088,"journal":{"name":"Journal of Physiology-London","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142985258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信