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Ghovanloo MR, Tyagi S, Zhao P, Effraim PR, Dib-Hajj SD, Waxman SG. Sodium currents in naïve mouse dorsal root ganglion neurons: No major differences between sexes. Channels (Austin) 2024; 18:2289256. [PMID: 38055732 PMCID: PMC10761158 DOI: 10.1080/19336950.2023.2289256] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 11/23/2023] [Indexed: 12/08/2023] Open
Abstract
Sexual dimorphism has been reported in multiple pre-clinical and clinical studies on pain. Previous investigations have suggested that in at least some states, rodent dorsal root ganglion (DRG) neurons display differential sex-dependent regulation and expression patterns of various proteins involved in the pain pathway. Our goal in this study was to determine whether sexual dimorphism in the biophysical properties of voltage-gated sodium (Nav) currents contributes to these observations in rodents. We recently developed a novel method that enables high-throughput, unbiased, and automated functional analysis of native rodent sensory neurons from naïve WT mice profiled simultaneously under uniform experimental conditions. In our previous study, we performed all experiments in neurons that were obtained from mixed populations of adult males or females, which were combined into single (combined male/female) data sets. Here, we have re-analyzed the same previously published data and segregated the cells based on sex. Although the number of cells in our previously published data sets were uneven for some comparisons, our results do not show sex-dependent differences in the biophysical properties of Nav currents in these native DRG neurons.
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Affiliation(s)
- Mohammad-Reza Ghovanloo
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
- Center for Neuroscience & Regeneration Research, Yale University, West Haven, CT, USA
- Neuro-Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - Sidharth Tyagi
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
- Center for Neuroscience & Regeneration Research, Yale University, West Haven, CT, USA
- Neuro-Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
- Medical Scientist Training Program, Yale University School of Medicine, New Haven, CT, USA
| | - Peng Zhao
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
- Center for Neuroscience & Regeneration Research, Yale University, West Haven, CT, USA
- Neuro-Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - Philip R. Effraim
- Center for Neuroscience & Regeneration Research, Yale University, West Haven, CT, USA
- Neuro-Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
- Department of Anesthesiology, Yale University School of Medicine, New Haven, CT, USA
| | - Sulayman D. Dib-Hajj
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
- Center for Neuroscience & Regeneration Research, Yale University, West Haven, CT, USA
- Neuro-Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - Stephen G. Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
- Center for Neuroscience & Regeneration Research, Yale University, West Haven, CT, USA
- Neuro-Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
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Liu M, Yi S, Yu H, Zhang T, Dong F, Zhu L. Underlying Mechanisms for the Sex- and Chemical-Specific Hepatotoxicity of Perfluoroalkyl Phosphinic Acids in Common Carp ( Cyprinus carpio). Environ Sci Technol 2023; 57:14515-14525. [PMID: 37728733 DOI: 10.1021/acs.est.3c04964] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
The hepatotoxicities of perfluoroalkyl and polyfluoroalkyl substances (PFASs) have been extensively investigated, while little is known about the sex-specific differences. In this study, common carp were exposed to the emerging perfluoroalkyl phosphinic acids (6:6 and 8:8 PFPiAs) for 14 days to disclose sex-specific hepatotoxicity. Apparent hepatotoxicity, including cell necrosis, apoptosis, and steatosis, was observed in both male and female carp liver. The observed hepatocyte steatosis was predominantly attributed to the dysregulation of hepatic lipid metabolism but was based on sex-specific mechanisms. It was manifested as inhibited oxidative decomposition of fatty acids (FAs) in the female liver, whereas it enhanced the uptake of FAs into the male liver, both of which led to excessive lipid accumulation. Untargeted lipidomics validated that the metabolism pathways of FA, sphingolipid, glycerolipid, and glycerophospholipid were disrupted by both compounds, leading to the generation of reactive oxygen species and oxidative stress. The oxidative stress further evolved into inflammation, manifested as promoted expression of proinflammatory cytokines and repressed expression of anti-inflammatory cytokines. Consistently, all of the changes were more noticeable in male carp, suggesting that male fish were more susceptible to PFPiA disruption. 8:8 PFPiA was less accumulated but caused stronger hepatotoxicity than 6:6 PFPiA, possibly because of the stronger binding capacity of 8:8 PFPiA to nuclear transcription factors mediating lipid metabolism and inflammation. The findings of this study highlight the significance of sex- and chemical-dependent bioaccumulation and the toxicity of PFASs in organisms.
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Affiliation(s)
- Menglin Liu
- Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
- School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Henan Normal University, Xinxiang 453007, China
| | - Shujun Yi
- Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Hao Yu
- School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Henan Normal University, Xinxiang 453007, China
| | - Tianxu Zhang
- Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Fengfeng Dong
- Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Lingyan Zhu
- Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
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Ulbricht RJ, Rivas CA, Marino H, Snyder E, James D, Makhloufi J, Johnson N, Zimmerman S, Wang J. Sex-specific effect of P2Y 2 purinergic receptor on glucose metabolism during acute inflammation. Front Endocrinol (Lausanne) 2023; 14:1248139. [PMID: 37701898 PMCID: PMC10494456 DOI: 10.3389/fendo.2023.1248139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 08/14/2023] [Indexed: 09/14/2023] Open
Abstract
The sex of an animal impacts glucose sensitivity, but little information is available regarding the mechanisms causing that difference, especially during acute inflammation. We examined sex-specific differences in the role of the P2Y2 receptor (P2Y2R) in glucose flux with and without LPS challenge. Male and female wild-type and P2Y2R knockout mice (P2Y2R-/-) were injected with LPS or saline and glucose tolerance tests (GTT) were performed. P2Y2R, insulin receptor, and GLUT4 transporter gene expression was also evaluated. Female mice had reduced fasting plasma glucose and females had reduced glucose excursion times compared to male mice during GTT. P2Y2R-/- males had significantly decreased glucose flux throughout the GTT as compared to all female mice. Acute inflammation reduced fasting plasma glucose and the GTT area under the curve in both sexes. While both wild-type and P2Y2R-/- male animals displayed reduced fasting glucose in LPS treatment, female mice did not have significant difference in glucose tolerance, suggesting that the effects of P2Y2R are specific to male mice, even under inflammatory conditions. Overall, we conclude that the role for the purinergic receptor, P2Y2R, in regulating glucose metabolism is minimal in females but plays a large role in male mice, particularly in the acute inflammatory state.
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Affiliation(s)
- Randi J. Ulbricht
- Department of Biomedical Sciences, Missouri State University, Springfield, MO, United States
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Bkaily G, Simon Y, Normand A, Jazzar A, Najibeddine H, Khalil A, Jacques D. Short-Communication: Short-Term Treatment with Taurine Prevents the Development of Cardiac Hypertrophy and Early Death in Hereditary Cardiomyopathy of the Hamster and Is Sex-Dependent. Nutrients 2022; 14:nu14163287. [PMID: 36014791 PMCID: PMC9412608 DOI: 10.3390/nu14163287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/09/2022] [Accepted: 08/10/2022] [Indexed: 12/02/2022] Open
Abstract
Premature death due to heart failure is a major health problem. Taurine is a non-essential amino acid that has received much attention. However, although many studies have been carried out on the beneficial effects of taurine in cardiac pathophysiology, no studies have investigated the effect of taurine treatment on the development of hereditary cardiomyopathy (HCM) associated with hypertrophy, heart failure, and early death. This study aims to verify whether short-term treatment (20 days) with taurine in tap water prevents the development of hypertrophy and premature death in hereditary cardiomyopathy of the hamster (HCMH) of the line UM-X7.1 and if its effect is sex-dependent. Our results show that treatment for 20 days with taurine (250 mg/kg/day or 25 mg/animal/day) during the development of the hypertrophic phase (220 days old) significantly decreased (p < 0.01) the heart weight to body weight ratio in male HCMHs without affecting the female. During the 20 days (220−240 days old), there were nearly 40% premature deaths in non-treated males HCMHs and 50% in female HCMHs. Treatment for 20 days wholly and significantly prevented early death in both males and females HCMHs. Our results demonstrate that short-term treatment with taurine prevents the development of cardiac hypertrophy associated with HCM in a sex-dependent manner; however, it prevents early death in a sex-independent fashion. Our results suggest that taurine supplementation could be used to treat HCM.
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Affiliation(s)
- Ghassan Bkaily
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
- Correspondence: (G.B.); (D.J.)
| | - Yanick Simon
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
| | - Alexandre Normand
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
| | - Ashley Jazzar
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
| | - Houssein Najibeddine
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
| | - Abdelouahed Khalil
- Department of Medicine, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
| | - Danielle Jacques
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
- Correspondence: (G.B.); (D.J.)
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Huang M, Liu K, Wei Z, Feng Z, Chen J, Yang J, Zhong Q, Wan G, Kong XJ. Serum Oxytocin Level Correlates With Gut Microbiome Dysbiosis in Children With Autism Spectrum Disorder. Front Neurosci 2021; 15:721884. [PMID: 34658767 PMCID: PMC8517432 DOI: 10.3389/fnins.2021.721884] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 09/15/2021] [Indexed: 12/27/2022] Open
Abstract
To investigate the levels of serum oxytocin (OT) in children with autism spectrum disorder (ASD) and explore the association between OT levels and gut microbiota relative abundances, we recruited 39 children with ASD children-mother dyads and 44 healthy controls. Serum OT levels were determined via enzyme-linked immunosorbent assay and gut microbiota abundances were determined by 16S rRNA sequencing. We found that the OT level of ASD was lower than the healthy control group overall (P < 0.05). Furthermore, we present preliminary evidence of gut microbiome dysbiosis observed among children with ASD to lower levels of OT based on correlational analysis between serum OT and specific gut microbiota abundances (P < 0.05). We also found sex-related differences in serum OT levels and GIS index (P < 0.05). However, the generalizability of findings relevant to females with ASD require further validation in future studies involving larger sample sizes and balanced sex distributions due to the small number of females involved in this study. Nonetheless, these new findings further our understanding of the effects of low serum OT levels among individuals with ASD, which provides preliminary evidence in hopes of guiding future study design or mechanistic studies. The findings of the present study may be suggestive of potential ASD subtypes based on ASD severity and gut microbiome composition that may facilitate the prediction of the therapeutic responses of OT among those with ASD.
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Affiliation(s)
- Minshi Huang
- Department of Child Psychology and Rehabilitation, Affiliated Shenzhen Maternity and Child Healthcare Hospital, Southern Medical University, Shenzhen, China
| | - Kevin Liu
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - Zhen Wei
- Department of Child Psychology and Rehabilitation, Affiliated Shenzhen Maternity and Child Healthcare Hospital, Southern Medical University, Shenzhen, China
| | - Zhe Feng
- Department of Child Psychology and Rehabilitation, Affiliated Shenzhen Maternity and Child Healthcare Hospital, Southern Medical University, Shenzhen, China
| | - Jierong Chen
- Department of Child Psychology and Rehabilitation, Affiliated Shenzhen Maternity and Child Healthcare Hospital, Southern Medical University, Shenzhen, China
| | - Jie Yang
- Department of Child Psychology and Rehabilitation, Affiliated Shenzhen Maternity and Child Healthcare Hospital, Southern Medical University, Shenzhen, China
| | - Qin Zhong
- Department of Child Psychology and Rehabilitation, Affiliated Shenzhen Maternity and Child Healthcare Hospital, Southern Medical University, Shenzhen, China
| | - Guobin Wan
- Department of Child Psychology and Rehabilitation, Affiliated Shenzhen Maternity and Child Healthcare Hospital, Southern Medical University, Shenzhen, China
| | - Xue-Jun Kong
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
- Department of Medicine and Psychiatry, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States
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6
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Shao S, Li J, Chen S, Dong Y, Wang S, Zhu Z, Xie L, Li H. Sex-dependent expression of N-cadherin-GluA1 pathway-related molecules in the prefrontal cortex mediates anxiety-like behavior in male offspring following prenatal stress. Stress 2021; 24:612-620. [PMID: 34184955 DOI: 10.1080/10253890.2021.1942829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Prenatal stress (PS) affects neurodevelopment and increases the risk for anxiety in adolescence in male offspring, but the mechanism is still unclear. N-Cadherin regulates the expression of AMPA receptors (AMPARs), which mediate anxiety by modulating network excitability in the prefrontal cortex (PFC). Our results revealed that in adolescent male, but not female, offspring rats, PS induced anxiety-like behavior, as assessed by the open field test (OFT). Furthermore, N-cadherin and AMPAR subunit GluA1 were colocalized in the PFC, and the expression of the N-cadherin and the GluA1 decreased following PS exposure in male offspring rats. We also found that the AMPAR agonist CX546 did not alleviate anxiety-like behavior in adolescent male offspring rats; however, it increased the expression of GluA1 in the PFC but did not alter the expression of N-cadherin. In conclusion, our study suggested that the N-cadherin-GluA1 pathway in the PFC mediates anxiety-like behavior in adolescent male offspring rats and that N-cadherin might be required for sex differences in the effect of PS on adolescent offspring.
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Affiliation(s)
- Shuya Shao
- Department of Neonatology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Jing Li
- Department of Neonatology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Shengquan Chen
- Department of Neonatology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - YanKai Dong
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Maternal and Infant Health Research Institute and Medical College, Northwestern University, Xi'an, China
| | - Shang Wang
- Department of Neonatology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Zhongliang Zhu
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Maternal and Infant Health Research Institute and Medical College, Northwestern University, Xi'an, China
| | - Longshan Xie
- Department of Functional Neuroscience, The First People's Hospital of Foshan (The Affiliated Foshan Hospital of Sun Yat-sen University), Foshan, China
| | - Hui Li
- Department of Neonatology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
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Bharadwaj VN, Copeland C, Mathew E, Newbern J, Anderson TR, Lifshitz J, Kodibagkar VD, Stabenfeldt SE. Sex-Dependent Macromolecule and Nanoparticle Delivery in Experimental Brain Injury. Tissue Eng Part A 2020; 26:688-701. [PMID: 32697674 PMCID: PMC7398445 DOI: 10.1089/ten.tea.2020.0040] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 04/09/2020] [Indexed: 02/07/2023] Open
Abstract
The development of effective therapeutics for brain disorders is challenging, in particular, the blood-brain barrier (BBB) severely limits access of the therapeutics into the brain parenchyma. Traumatic brain injury (TBI) may lead to transient BBB permeability that affords a unique opportunity for therapeutic delivery via intravenous administration ranging from macromolecules to nanoparticles (NPs) for developing precision therapeutics. In this regard, we address critical gaps in understanding the range/size of therapeutics, delivery window(s), and moreover, the potential impact of biological factors for optimal delivery parameters. Here we show, for the first time, to the best of our knowledge, that 24-h postfocal TBI female mice exhibit a heightened macromolecular tracer and NP accumulation compared with male mice, indicating sex-dependent differences in BBB permeability. Furthermore, we report for the first time the potential to deliver NP-based therapeutics within 3 days after focal injury in both female and male mice. The delineation of injury-induced BBB permeability with respect to sex and temporal profile is essential to more accurately tailor time-dependent precision and personalized nanotherapeutics. Impact statement In this study, we identified a sex-dependent temporal profile of blood/brain barrier disruption in a preclinical mouse model of traumatic brain injury (TBI) that contributes to starkly different macromolecule and nanoparticle delivery profiles post-TBI. The implications and potential impact of this work are profound and far reaching as it indicates that a demand of true personalized medicine for TBI is necessary to deliver the right therapeutic at the right time for the right patient.
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Affiliation(s)
- Vimala N. Bharadwaj
- School of Biological and Health Systems Engineering, Ira A. Fulton Schools of Engineering, Arizona State University, Tempe, Arizona, USA
| | - Connor Copeland
- School of Biological and Health Systems Engineering, Ira A. Fulton Schools of Engineering, Arizona State University, Tempe, Arizona, USA
| | - Ethan Mathew
- School of Biological and Health Systems Engineering, Ira A. Fulton Schools of Engineering, Arizona State University, Tempe, Arizona, USA
| | - Jason Newbern
- School of Life Sciences, Arizona State University, Tempe, Arizona, USA
| | - Trent R. Anderson
- Basic Medical Sciences, University of Arizona, College of Medicine–Phoenix, Phoenix, Arizona, USA
| | - Jonathan Lifshitz
- Department of Child Health, University of Arizona, College of Medicine–Phoenix, Phoenix, Arizona, USA
- BARROW Neurological Institute at Phoenix Children's Hospital, Phoenix, Arizona, USA
- Phoenix VA Health Care System, Phoenix, Arizona, USA
| | - Vikram D. Kodibagkar
- School of Biological and Health Systems Engineering, Ira A. Fulton Schools of Engineering, Arizona State University, Tempe, Arizona, USA
| | - Sarah E. Stabenfeldt
- School of Biological and Health Systems Engineering, Ira A. Fulton Schools of Engineering, Arizona State University, Tempe, Arizona, USA
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Patil MJ, Green DP, Henry MA, Akopian AN. Sex-dependent roles of prolactin and prolactin receptor in postoperative pain and hyperalgesia in mice. Neuroscience 2013; 253:132-41. [PMID: 23994182 DOI: 10.1016/j.neuroscience.2013.08.035] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Revised: 08/06/2013] [Accepted: 08/20/2013] [Indexed: 11/29/2022]
Abstract
Although surgical trauma activates the anterior pituitary gland and elicits an increase in prolactin (PRL) serum levels that can modulate nociceptive responses, the role of PRL and the PRL-receptor (PRL-R) in thermal and mechanical hyperalgesia in postoperative pain is unknown. Acute postoperative pain condition was generated with the use of the hindpaw plantar incision model. Results showed endogenous PRL levels were significantly increased in serum, operated hindpaw and spinal cords of male and female rats 24h after incision. These alterations were especially pronounced in females. We then examined the role of the PRL system in thermal and mechanical hyperalgesia in male and female mice 3-168 h after plantar incision with the use of knock-out (KO) mice with PRL or PRL-R gene ablations and in wild-type (WT) mice. WT mice showed postoperative cold hyperalgesia in a sex-dependent manner (only in females), but with no effect on heat hyperalgesia or mechanical allodynia in either sex. Studies in KO mice showed no effect of PRL and PRL-R gene ablation on heat and cold hyperalgesia in male mice, while heat hyperlgesia were reduced 3-72 h post-surgery in female PRL and PRL-R KO mice. In contrast, PRL and PRL-R ablations significantly attenuated mechanical allodynia 3-72 h post-surgery in both male and female mice. Overall, we found elevated PRL levels in serum, hindpaws and spinal cords after incision, and identify a contributory role for the PRL system in postoperative pain responses to thermal stimuli in females and to mechanical stimuli in both males and females.
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Affiliation(s)
- M J Patil
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, TX 78229, USA
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