Alexandre M do Nascimento, Ana M Rodrigues, Heloisa E G Ramos, Beatriz C de Moraes, Raphael S Santos, Camila S Dale, Deborah Schechtman
{"title":"PLCγ has a dual role in capsaicin-triggered neurogenic inflammation promoting mechanical hypersensitivity and edema in male mice.","authors":"Alexandre M do Nascimento, Ana M Rodrigues, Heloisa E G Ramos, Beatriz C de Moraes, Raphael S Santos, Camila S Dale, Deborah Schechtman","doi":"10.1152/ajpcell.00154.2025","DOIUrl":"10.1152/ajpcell.00154.2025","url":null,"abstract":"<p><p>Understanding the signaling mechanisms leading to neurogenic inflammation, a process found in chronic pain, psoriasis and migraine, is key for the development of more effective analgesics. A key player in the onset of this inflammation is transient receptor potential cation channel, subfamily V, member 1 (TRPV1), an ion channel abundant at the free terminals of nociceptors, which can be directly activated by capsaicin (CAP), acidic pH or noxious heat, and indirectly through phospholipase C-γ (PLCγ), which promotes cleavage of the inhibitory phosphatidylinositol-4,5-bisphosphate from the channel. In turn, PLCγ is activated via its phosphorylation by growth factor receptor tyrosine kinases, such as the high affinity nerve growth factor receptor, tropomyosin kinase A (TrkA). We previously developed a permeable phosphopeptide (TAT-pQYP) that binds to PLCγ, preventing lipase anchoring to TrkA, and hence its phosphorylation/activation, and showed that PLCγ is key for mechanical hypersensitivity in CFA-induced inflammation. Herewith, we investigate the role of PLCγ in an acute model of inflammatory nociception induced by the subcutaneous injection of CAP in the hind paw of male mice. This model elicited a two phase response, the first related to TRPV1's sensitization and the latter to neurogenic inflammation. TAT-pQYP did not alter the TRPV1-mediated chemonociceptive response and neurogenic signaling itself, but it was able to disrupt PLCγ signaling, reverting nerve growth factor/TrkA-dependent mechanical hypersensitivity in nociceptors, and returning paw diameter to baseline levels by disrupting vascular endothelial growth factor A/endothelial nitric oxide synthase signaling in endothelial cells. Altogether, our results show that TAT-pQYP disrupts PLCγ signaling in CAP-triggered neurogenic inflammation, leading to an anti-inflammatory and antinociceptive effect without interfering with TRPV1 chemosensitivity and neuropeptides activity. PLCγ represents a potential target to relieve neurogenic inflammation-dependent pain while preserving TRPV1's physiological activity.<b>NEW & NOTEWORTHY</b> When activated, TRPV1 promotes neurogenic inflammation via neuropeptide signaling. However, drugs designed to directly block TRPV1 may impair its nociceptive roles, essential for tissue preservation. In this work, pain and swelling caused by neurogenic inflammation were mitigated after blocking PLCγ's activity, modulating TRPV1's activity without affecting normal chemosensitivity. This suggests that blocking PLCγ could be a new approach for the development of painkillers maintaining the physiological detection of harmful stimuli.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C821-C833"},"PeriodicalIF":4.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144820291","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":"Asymmetric FGF receptor dimerization: implications for FGF23 biology and drug discovery.","authors":"Mohammed S Razzaque, Moosa Mohammadi","doi":"10.1152/ajpcell.01020.2024","DOIUrl":"10.1152/ajpcell.01020.2024","url":null,"abstract":"<p><p>Fibroblast growth factor 23 (FGF23) requires both αKlotho and heparan sulfate proteoglycans (HSPGs) as obligatory coreceptors to bind, dimerize, and activate its FGF receptors (FGFRs) in the kidney, thereby regulating mineral ion and vitamin D homeostasis. Cryogenic electron microscopy studies reveal that FGF23 signaling proceeds through an asymmetric 1:2:1:1 FGF23-FGFR-αKlotho-HS assembly. According to this structural model, αKlotho simultaneously anchors FGF23 and one FGFR chain, referred to as the primary receptor (FGFR<sup>P</sup>), to form a 1:1:1 FGF23-FGFR<sup>P</sup>-αKlotho triplex, which boosts FGF23-FGFR<sup>P</sup> interaction. Subsequently, the HS coreceptor aids the triplex in recruiting a second FGFR chain, or secondary receptor (FGFR<sup>S</sup>), leading to asymmetric receptor dimerization. This recruitment is driven by the interactions of FGF23 and FGFR<sup>P</sup> from the triplex with the secondary receptor, with no direct involvement from αKlotho. This model outlines the possibility of heterodimerization among the renal cognate receptors of FGF23 (namely, FGFR1c, FGFR3c, and FGFR4), which may introduce signaling diversity affecting phosphate and vitamin D regulation. In addition, it proposes that kidney-specific HS structures could cooperate with renal αKlotho to home FGF23 to renal tissues. The proposed FGF23 signaling assembly provides a framework for further investigation and may inform the development of FGF23 antagonists or partial agonists for treating disorders associated with phosphate and vitamin D dysregulation.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C904-C910"},"PeriodicalIF":4.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144870895","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":"Reversible oxidative modifications partially cause myofibrillar active and passive force decline in early phase of immobilization.","authors":"Daiki Watanabe, Takaaki Mishima, Taku Hamada","doi":"10.1152/ajpcell.00554.2025","DOIUrl":"10.1152/ajpcell.00554.2025","url":null,"abstract":"<p><p>Muscle immobilization leads to a decrease in muscle fiber size and contractile function, partly due to a decline in myofibrillar force. In this study, we examined the effects of reversible oxidative modifications on the decline of myofibrillar function during the early phase of immobilization. One leg of male C57BL6 mice was immobilized for 3 days and 7 days, whereas the contralateral leg was used as a nontreated (NT) control. After the given immobilization periods, mechanically skinned fibers were prepared from the gastrocnemius muscle, and myofibrillar active and passive forces were assessed. Myofibrillar specific force decreased after 7 days of immobilization, although myofibrillar Ca<sup>2+</sup> sensitivity remained unchanged. The decreased specific force was partially restored by a treatment with dithiothreitol (DTT), a reducing agent, only when applied to nonactivated fibers, not activated fibers. In addition, 3-morpholinosydnonimine and peroxynitrite (ONOO<sup>-</sup>) decreased maximal force in nonactivated fibers from NT but not immobilized (Im) muscles. Myofibrillar passive force decreased after 7 days of immobilization. DTT treatment increased passive force in both NT and Im fibers, with a greater improvement seen in Im fibers. Furthermore, treatment with oxidized glutathione before DTT treatment decreases passive force in both NT and Im fibers, with a greater reduction seen in NT fibers. These results suggest that reversible oxidative modifications partially contribute to the impairments in both myofibrillar active and passive forces, at least in the early phase of immobilization. Specifically, ONOO<sup>-</sup> and <i>S</i>-glutathionylation likely play an important role in active and passive force, respectively.<b>NEW & NOTEWORTHY</b> Muscle disuse negatively affects muscle quality, in part due to an impairment of myofibril. This study was the first to reveal that reducing treatment can partially restore the decreased myofibrillar maximal force and passive force observed during the early phase of immobilization. Furthermore, the results suggest that peroxynitrite-induced modification and <i>S</i>-glutathionylation of titin likely contribute to the decreases in active and passive forces, respectively. This study provides valuable insights for the population affected by muscle immobilization.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C939-C952"},"PeriodicalIF":4.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144938903","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}
Stephanie M Bilinovich, Surya B Chhetri, Jackson T Mitchell, Gage O Leighton, Vladislav Jdanov, Jacob K Zieba, Taylor W Cook, Krysta L Engel, Robert M Vaughan, Humza Bhatti, Sadie L Heeringa, Amy M Wilstermann, Sophie Vanderweele, Akansha S Das, Emily C Sherry, Stephen A Duncan, Katie L Uhl, David C Hinds, Mark Mackiewicz, Sarah K Meadows, Kimberly M Newberry, E Christopher Partridge, Sara G Cline, C Joy Shepard, D Casey Smith, Antonio Bradley, Daniel Vogt, Daniel B Campbell, Lucas Pozzo-Miller, Caleb P Bupp, Austin J Goodyke, Surender Rajasekaran, Rebecca C Knickmeyer, Benjie Blair, Connie M Krawczyk, Timothy J Triche, Richard M Myers, Eric M Mendenhall, David C Williams, Jeremy W Prokop
{"title":"Methyl-CpG-binding domain as a protein interaction partner in promoter regulation and neurodevelopment through evolutionary expanded entanglement.","authors":"Stephanie M Bilinovich, Surya B Chhetri, Jackson T Mitchell, Gage O Leighton, Vladislav Jdanov, Jacob K Zieba, Taylor W Cook, Krysta L Engel, Robert M Vaughan, Humza Bhatti, Sadie L Heeringa, Amy M Wilstermann, Sophie Vanderweele, Akansha S Das, Emily C Sherry, Stephen A Duncan, Katie L Uhl, David C Hinds, Mark Mackiewicz, Sarah K Meadows, Kimberly M Newberry, E Christopher Partridge, Sara G Cline, C Joy Shepard, D Casey Smith, Antonio Bradley, Daniel Vogt, Daniel B Campbell, Lucas Pozzo-Miller, Caleb P Bupp, Austin J Goodyke, Surender Rajasekaran, Rebecca C Knickmeyer, Benjie Blair, Connie M Krawczyk, Timothy J Triche, Richard M Myers, Eric M Mendenhall, David C Williams, Jeremy W Prokop","doi":"10.1152/ajpcell.00749.2024","DOIUrl":"10.1152/ajpcell.00749.2024","url":null,"abstract":"<p><p>There is increasing evidence that the methyl-binding domain (MBD) is a protein-protein interaction motif that can function independently of methylated DNA binding. The MBD proteins found throughout plants and invertebrates duplicated into multiple vertebrate DNA and non-DNA-binding members (MBD1, MBD2, MBD3, MBD4, MBD5, MBD6, MECP2, BAZ2A, BAZ2B, SETDB1, and SETDB2). Although many invertebrate species possess MBD proteins that can bind and recognize DNA methylation, the DNA-binding function has been independently lost multiple times, with only minor alterations to the protein interaction residues. The nucleosome remodeling and deacetylase (NuRD) complex, which interacts with MBD2/3 and is colocalized with MBD1/4 ChIP-Seq, is maintained in species where MBD2/3 cannot bind to DNA. NuRD ChIP-seq data from HepG2 cell line, human induced pluripotent stem cells (iPSCs), and human iPSC-derived liver cells suggest that the NuRD complex is highly localized to nonmethylated CpG-rich housekeeping gene promoter elements, which are essential in organogenesis and maintained within the <i>Drosophila melanogaster</i> MBD2/3 non-DNA-binding system. Integration of MBD interaction proteins and NuRD gene expression from >115 million cells of single-cell RNA-seq, along with thousands of bulk tissue profiles, highlights a critical role of MBD3, MECP2, and GATAD2B in brain development and intellectual disability syndromes that is maintained throughout invertebrate neural development and likely involves evolutionary expanded entanglement as the vertebrate MBD proteins expanded. This work suggests that MBD has a largely unexplored role as a critical protein interaction motif that is evolutionarily conserved for regulating enhancers and promoters.<b>NEW & NOTEWORTHY</b> The evolution of the methyl-binding domain (MBD) suggests a shared function in gene regulation, from plants to humans, with the conservation of non-DNA-interacting amino acids critical for protein-protein interactions. The MBD-regulated NuRD complex localizes to promoters of housekeeping genes with hypomethylated CpG islands. Expression profiles suggest a shared role for NuRD complex components in neurodevelopment, where the MBD3 and GATAD2B subcomplex of NuRD may be underexplored due to its non-DNA-binding biology.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C848-C867"},"PeriodicalIF":4.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144717289","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":"Pericytes in tissue fibrosis.","authors":"Izabela Tuleta, Nikolaos G Frangogiannis","doi":"10.1152/ajpcell.00403.2025","DOIUrl":"10.1152/ajpcell.00403.2025","url":null,"abstract":"<p><p>Pericytes are mural cells, embedded within the microvascular basement membrane and primarily involved in preservation of vessel integrity and regulation of vascular permeability and blood flow. Their study poses major challenges due to the absence of specific and reliable markers for their identification. Emerging evidence suggests that, in addition to their involvement in the regulation of microvascular responses, pericytes may also play a central role in repair, inflammation, and fibrosis in many different organs. Following injury, pericytes may dissociate from endothelial cells, acquiring inflammatory and profibrotic phenotypes. Fibrogenic activation of pericytes has been reported in many different pathologic conditions and may involve stimulation by inflammatory cytokines, transforming growth factor-β, or platelet-derived growth factor-BB. Activated pericytes may stimulate fibrosis by secreting fibroblast-activating growth factors, by producing proteins involved in extracellular matrix remodeling, and by depositing structural and matricellular matrix proteins. Conflicting findings have been reported on the phenotypic plasticity of pericytes and their capacity to convert to fibroblasts and myofibroblasts. Organ-specific differences in pericyte populations and differences in sensitivity and specificity of the pericyte fate mapping and fibroblast identification strategies may account for the conflicting observations reported in various studies. This review manuscript deals with the fate, role, and mechanisms of activation of pericytes in tissue fibrosis. We discuss both the general mechanisms of pericyte activation and the organ-specific roles of pericytes in fibrotic conditions involving the kidney, liver, lung, heart, and central nervous system. Understanding the role of pericytes is important to develop effective therapies for fibrotic conditions.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C868-C886"},"PeriodicalIF":4.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12439126/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144833644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ralph A de Groot, Daan Reedijk, Quentin Faucher, Silvia M Mihăilă, Rosalinde Masereeuw
{"title":"Strategies for overcoming ABC transporter-mediated multidrug resistance in colorectal cancer.","authors":"Ralph A de Groot, Daan Reedijk, Quentin Faucher, Silvia M Mihăilă, Rosalinde Masereeuw","doi":"10.1152/ajpcell.00412.2025","DOIUrl":"10.1152/ajpcell.00412.2025","url":null,"abstract":"<p><p>Colorectal cancer (CRC) remains a leading cause of cancer-related mortality, with multidrug resistance (MDR) significantly limiting the effectiveness of chemotherapy. A major contributor to MDR is the overexpression of ATP-binding cassette (ABC) transporters, such as P-glycoprotein (<i>ABCB1/</i>P-gp), breast cancer resistance protein (<i>ABCG2/</i>BCRP), and multidrug resistance-associated proteins (<i>ABCC/</i>MRPs). These transporters actively efflux chemotherapeutic agents, reducing their intracellular drug accumulation and efficacy. This review outlines both clinical and emerging strategies that aim to overcome ABC transporter-mediated resistance in CRC. Herein, we detail the functional role of ABC transporters in CRC, followed by clinically tested approaches, such as pharmacological inhibitors, natural compound inhibitors, as well as nanoparticle-based drug delivery systems, that have been explored to circumvent resistance. In addition, we discuss emerging preclinical approaches, including CRISPR/Cas9 gene-editing, RNA interference, epigenetic modulators, and gut microbiome-targeted interventions, that hold promise for future therapeutic translation. By integrating clinically validated and experimental strategies, this review highlights the importance of a multimodal approach to effectively circumvent MDR in CRC and optimize personalized treatment strategies to improve clinical outcomes.<i>ABC transporters; chemoresistance; colorectal cancer; multidrug resistance; therapies</i>.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C699-C717"},"PeriodicalIF":4.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144641558","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}
He Zhou, Solange Abdulnour-Nakhoul, L Lee Hamm, Nazih L Nakhoul
{"title":"Rhbg interaction with CA-IV and its effects on NH<sub>3</sub>/NH<sub>4</sub><sup>+</sup> and CO<sub>2</sub> transport.","authors":"He Zhou, Solange Abdulnour-Nakhoul, L Lee Hamm, Nazih L Nakhoul","doi":"10.1152/ajpcell.00099.2025","DOIUrl":"10.1152/ajpcell.00099.2025","url":null,"abstract":"<p><p>Renal Rhesus type B glycoprotein (Rhbg) is a glycosylated mammalian NH<sub>3</sub>/NH<sub>4</sub><sup>+</sup> transporter expressed in α-intercalated cells of the collecting duct. Carbonic anhydrase-IV (CA-IV) is also expressed in the mammalian kidney, where it catalyzes the reversible hydration of CO<sub>2</sub>. This study aims to demonstrate: <i>1</i>) whether Rhbg and CA-IV proteins physically interact; and <i>2</i>) if this interaction functionally affects transport of NH<sub>3</sub>/NH<sub>4</sub><sup>+</sup> and possibly CO<sub>2</sub>. We measured transport of NH<sub>4</sub><sup>+</sup>, NH<sub>3</sub>, and CO<sub>2</sub> in four groups of <i>Xenopus</i> oocytes. In the first group, we coexpressed Rhbg with CA-IV and compared the measurements to three groups of oocytes expressing either Rhbg or CA-IV or injected with H<sub>2</sub>O. We used ion-selective microelectrodes to measure surface pH, to monitor NH<sub>3</sub> transport, and intracellular pH to monitor NH<sub>4</sub><sup>+</sup> and CO<sub>2</sub> transport. We also used a two-electrode voltage clamp to measure current changes caused by electrogenic NH<sub>4</sub><sup>+</sup> transport. These parameters measured NH<sub>3</sub>/NH<sub>4</sub><sup>+</sup> and CO<sub>2</sub> transport in oocytes expressing Rhbg and/or CA. Our results indicate that: <i>1</i>) Rhbg and CA-IV were coimmunoprecipitated, suggesting a physical interaction; and <i>2</i>) coexpressing CA-IV with Rhbg: <i>i</i>) inhibited electrogenic NH<sub>4</sub><sup>+</sup> transport by Rhbg in the presence and absence of CO<sub>2</sub>; <i>ii</i>) reduced NH<sub>3</sub> transport by Rhbg only in the presence of CO<sub>2</sub>; and <i>iii</i>) had no detectable effect on CO<sub>2</sub> transport by Rhbg. We demonstrated for the first time that Rhbg and CA-IV physically interact, and this interaction has inhibitory effects on Rhbg function but not CA-IV. The interaction of Rhbg and CA-IV is important to explain their role in renal acid-base homeostasis.<b>NEW & NOTEWORTHY</b> Our study revealed the complex regulation of NH<sub>3</sub>/NH<sub>4</sub><sup>+</sup> transport, highlighting the roles of Rhbg, CA-IV, and environmental factors such as CO<sub>2</sub> concentration. These interactions are critical to our understanding of NH<sub>3</sub>/NH<sub>4</sub><sup>+</sup> transport and regulation. Our findings lay a strong foundation for future investigations into the molecular dynamics among these transport proteins and their physiological significance. These studies are essential to fully understand how these mechanisms influence renal ammonia handling, urinary acidification, and systemic pH balance.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C887-C903"},"PeriodicalIF":4.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144854248","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}
Camila Astudillo-Guerrero, Daniela Fernandois, Emilie Caron, Vincent Prevot, Joshua P Thaler, Mauricio D Dorfman, Gonzalo Cruz
{"title":"Hypothalamic gliosis as a potential mediator of improved glucose tolerance induced by time-restricted feeding in obese mice.","authors":"Camila Astudillo-Guerrero, Daniela Fernandois, Emilie Caron, Vincent Prevot, Joshua P Thaler, Mauricio D Dorfman, Gonzalo Cruz","doi":"10.1152/ajpcell.00357.2025","DOIUrl":"10.1152/ajpcell.00357.2025","url":null,"abstract":"<p><p>Time-restricted feeding (TRF) has been shown to improve glycemic control, reduce liver fat, and decrease cardiovascular risk in humans and diet-induced obese (DIO) mice. However, the mechanisms associated with this improvement are not completely understood. High-fat diet (HFD)-associated hypothalamic inflammation and glial activation promote obesity and metabolic dysfunction, raising the possibility that TRF mitigates these factors. Specifically, TRF increases circulating levels of β-hydroxybutyrate (BHB), a ketone body that crosses the blood-brain barrier and has anti-inflammatory properties. Here, we evaluated whether the beneficial effects of TRF are associated with changes in hypothalamic inflammation and gliosis. Furthermore, we assessed the ability of peripheral or central administration of BHB to mimic the metabolic phenotype of TRF. Consistent with prior studies in HFD-fed mice, weight loss induced by TRF was modest, due to a transient decrease in food intake offset by a persistent reduction in energy expenditure. Despite the limited effect on body weight and adiposity, TRF markedly improved glucose tolerance in DIO mice, restoring glucose homeostasis to the level of chow-fed controls. Unexpectedly, TRF increased hypothalamic markers of gliosis in DIO mice. Finally, although TRF induced the predicted rise in circulating BHB levels, chronic systemic or ICV administration of BHB had no effect on glucose tolerance and hypothalamic gliosis. Together, these data suggest that increased hypothalamic gliosis may contribute to the improvement of glucose tolerance induced by TRF in DIO mice.<b>NEW & NOTEWORTHY</b> This study shows that time-restricted feeding (TRF) improves glucose tolerance in obese mice independently of weight loss. Surprisingly, this benefit is linked to increased hypothalamic gliosis, challenging the view that gliosis is solely detrimental in obesity. Although TRF elevates circulating β-hydroxybutyrate (BHB), peripheral and central BHB delivery fails to mimic TRF's glycemic benefits or affect hypothalamic gliosis. These findings suggest gliosis may play a previously unrecognized role in mediating TRF's metabolic benefits.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C834-C847"},"PeriodicalIF":4.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12377117/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144752050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Cellular and molecular mechanisms of cancer drug resistance.","authors":"Miroslava Matuskova, Andrea Babelova","doi":"10.1152/ajpcell.00615.2025","DOIUrl":"10.1152/ajpcell.00615.2025","url":null,"abstract":"","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C936-C938"},"PeriodicalIF":4.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144870896","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}
Negar Mir, Sulayman A Lyons, Zhengzhang Guo, Safa Khadija Mirza, Wenbo Tan, Ashley J Peckett, Jacqueline L Beaudry
{"title":"Acute antilipolytic effects of elevated levels of corticosterone in differentiated murine white adipocytes.","authors":"Negar Mir, Sulayman A Lyons, Zhengzhang Guo, Safa Khadija Mirza, Wenbo Tan, Ashley J Peckett, Jacqueline L Beaudry","doi":"10.1152/ajpcell.00353.2024","DOIUrl":"10.1152/ajpcell.00353.2024","url":null,"abstract":"<p><p>Glucocorticoids (GC) are a group of steroid hormones that affect white adipose tissue (WAT) lipogenesis (biosynthesis of triglycerides) and lipolysis (hydrolysis of triglycerides). At the cellular level, prolonged GC exposure promotes increases in WAT lipolysis through glucocorticoid receptor (GR) mediated mechanisms; however, elevated GC levels can decrease WAT lipolysis through unknown mechanisms that remain unclear. Evidence suggests that GCs may also have actions independent of GR binding, though how these GR-independent effects impact WAT lipolysis also remains unknown. Therefore, the objective of this study was to assess how elevated GCs impact WAT lipolysis through non-GR-mediated mechanisms. Mature white adipocytes (3T3-L1 cells) were acutely exposed to various GC concentrations (10-200 µM), and lipolytic rates were quantified in the presence or absence of lipolytic pathway inhibitors or siRNA GR. Contradictory to chronic in vitro and in vivo studies, acute (1-4 h), high GC levels (50-200 µM) significantly decreased basal lipolysis. These inhibitory effects persisted when the GR or gene transcription was blocked after 1 h, suggesting GCs inhibition of lipolysis occurred independent of GR-mediated pathways. Interestingly, 1 h of elevated GC exposure decreased hormone sensitive lipase (HSL) activity through a reduction of ser563 phosphorylation. However, this decrease in HSL activity was independent of cAMP signalling, as elevated GCs had no effect on cAMP or PKA activity relative to controls. Ex vivo adipose explant studies also revealed depot-specific suppression of lipolysis by corticosterone. Therefore, elevated GC levels can acutely decrease lipolysis in WAT independent of GR-mediated mechanisms, suggesting an alternative pathway in which GCs act to regulate lipolysis.<b>NEW & NOTEWORTHY</b> This research led to novel findings about acute, non-GR-mediated effects of elevated CORT on lipolysis in WAT. Most work has been done on lower GC levels and chronic durations, and does not fully capture the acute, non-GR-mediated effects of GCs in WAT. These acute, non-GR-mediated effects have been studied in tissues such as smooth muscle and bronchial epithelial cells, but to our knowledge, no study reported on such effects in WAT.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C972-C985"},"PeriodicalIF":4.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144938628","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}