1
|
do Espírito-Santo RF, Margerison SM, Zhang Y, Pak J, Ro JY, Da Silva JT. Age- and Sex-Dependent Effects of Moderate Exercise on Endogenous Pain Inhibition in Rats. Biomedicines 2024; 12:1122. [PMID: 38791084 PMCID: PMC11117727 DOI: 10.3390/biomedicines12051122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 04/26/2024] [Accepted: 05/15/2024] [Indexed: 05/26/2024] Open
Abstract
Diffuse noxious inhibitory controls (DNICs), or the pain inhibits pain phenomenon, refer to reduced pain-like behaviors that are displayed following a noxious conditioning stimulus located far from the test stimulus and have also been referred to as "descending control of nociception" when measured in awake-behaving animals. In this study, we sought to determine the impact of moderate long-term exercise on the DCN response and determine if this effect differed across age and sex. After a six-week exercise program consisting of 30 min of moderate treadmill running 5 days a week, the animals' forepaws were injected with capsaicin, and DCN responses were assessed using thermal withdrawal latencies of the hind paw. Young, exercised male and female rats displayed prolonged DCN responses relative to their sedentary counterparts, with the young exercised male group displaying longer-lasting DCN facilitation than the young exercised females. Exercise did not impact DCN responses in either male or female aged rats. Additionally, the serum testosterone levels did not change following exercise in any group. Importantly, the levels of corticosterone did not change following the exercise program, indicating that changes in the DCN response are not due to stress-induced analgesia. Our findings suggest that moderate exercise can facilitate the DCN response in young animals, even when this exercise does not change the levels of serum testosterone.
Collapse
Affiliation(s)
- Renan F. do Espírito-Santo
- Department of Neural and Pain Sciences, University of Maryland School of Dentistry, Baltimore, MD 21201, USA; (R.F.d.E.-S.); (S.M.M.); (Y.Z.); (J.P.); (J.Y.R.)
| | - Sarah M. Margerison
- Department of Neural and Pain Sciences, University of Maryland School of Dentistry, Baltimore, MD 21201, USA; (R.F.d.E.-S.); (S.M.M.); (Y.Z.); (J.P.); (J.Y.R.)
- Department of Physical Therapy and Rehabilitation Science, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Youping Zhang
- Department of Neural and Pain Sciences, University of Maryland School of Dentistry, Baltimore, MD 21201, USA; (R.F.d.E.-S.); (S.M.M.); (Y.Z.); (J.P.); (J.Y.R.)
| | - Joshua Pak
- Department of Neural and Pain Sciences, University of Maryland School of Dentistry, Baltimore, MD 21201, USA; (R.F.d.E.-S.); (S.M.M.); (Y.Z.); (J.P.); (J.Y.R.)
| | - Jin Y. Ro
- Department of Neural and Pain Sciences, University of Maryland School of Dentistry, Baltimore, MD 21201, USA; (R.F.d.E.-S.); (S.M.M.); (Y.Z.); (J.P.); (J.Y.R.)
| | - Joyce T. Da Silva
- Department of Neural and Pain Sciences, University of Maryland School of Dentistry, Baltimore, MD 21201, USA; (R.F.d.E.-S.); (S.M.M.); (Y.Z.); (J.P.); (J.Y.R.)
| |
Collapse
|
2
|
Hoegh M, Bannister K. Pain Science in Practice (Part 6): How Does Descending Modulation of Pain Work?. J Orthop Sports Phys Ther 2024; 54:1-4. [PMID: 38288567 DOI: 10.2519/jospt.2024.12112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
SYNOPSIS To understand the neuroscience of pain relief, one must know about the descending pain modulatory system. Neuronal pathways that originate in the brainstem and project to the spinal cord to modulate spinal neuronal activity provide a well-documented perspective on the mechanisms of analgesia that underpin pharmacological and nonpharmacological treatment options for people with musculoskeletal pain. Peripheral stimuli or signals from the cortex and subcortical regions of the brain can trigger the descending pain modulatory system (DPMS). The system helps explain how counter-stimulation techniques (eg, acupuncture and manual therapy), the patients' expectations and beliefs, and social or contextual factors could influence how people experience pain. J Orthop Sports Phys Ther 2024;54(2):1-4. doi:10.2519/jospt.2024.12112.
Collapse
Affiliation(s)
- Morten Hoegh
- Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Aalborg, Denmark
| | - Kirsty Bannister
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| |
Collapse
|
3
|
Kureshi S, Mendizabal M, Francis J, Djalilian HR. Conservative Management of Acute Sports-Related Concussions: A Narrative Review. Healthcare (Basel) 2024; 12:289. [PMID: 38338173 PMCID: PMC10855441 DOI: 10.3390/healthcare12030289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/09/2024] [Accepted: 01/22/2024] [Indexed: 02/12/2024] Open
Abstract
This review explores the application of the conservative management model for pain to sports-related concussions (SRCs), framing concussions as a distinct form of pain syndrome with a pathophysiological foundation in central sensitization. Drawing parallels with proven pain management models, we underscore the significance of a proactive approach to concussion management. Recognizing concussions as a pain syndrome allows for the tailoring of interventions in alignment with conservative principles. This review first covers the epidemiology and controversies surrounding prolonged concussion recovery and persistent post-concussion symptoms (PPCS). Next, the pathophysiology of concussions is presented within the central sensitization framework, emphasizing the need for early intervention to mitigate the neuroplastic changes that lead to heightened pain sensitivity. Five components of the central sensitization process specific to concussion injuries are highlighted as targets for conservative interventions in the acute period: peripheral sensitization, cerebral metabolic dysfunction, neuroinflammation, glymphatic system dysfunction, and pain catastrophizing. These proactive interventions are emphasized as pivotal in accelerating concussion recovery and reducing the risk of prolonged symptoms and PPCS, in line with the philosophy of conservative management.
Collapse
Affiliation(s)
- Sohaib Kureshi
- Neurosurgical Medical Clinic, San Diego, CA 92111, USA
- TBI Virtual, San Diego, CA 92111, USA
| | | | | | - Hamid R. Djalilian
- TBI Virtual, San Diego, CA 92111, USA
- Departments of Otolaryngology, Neurological Surgery, and Biomedical Engineering, University of California, Irvine, CA 92697, USA
| |
Collapse
|
4
|
Chen Q, Bharadwaj V, Irvine KA, Clark JD. Mechanisms and treatments of chronic pain after traumatic brain injury. Neurochem Int 2023; 171:105630. [PMID: 37865340 DOI: 10.1016/j.neuint.2023.105630] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 10/13/2023] [Accepted: 10/15/2023] [Indexed: 10/23/2023]
Abstract
While pain after trauma generally resolves, some trauma patients experience pain for months to years after injury. An example, relevant to both combat and civilian settings, is chronic pain after traumatic brain injury (TBI). Headache as well as pain in the back and extremities are common locations for TBI-related chronic pain to be experienced. TBI-related pain can exist alone or can exacerbate pain from other injuries long after healing has occurred. Consequences of chronic pain in these settings include increased suffering, higher levels of disability, serious emotional problems, and worsened cognitive deficits. The current review will examine recent evidence regarding dysfunction of endogenous pain modulatory mechanisms, neuroplastic changes in the trigeminal circuitry and alterations in spinal nociceptive processing as contributors to TBI-related chronic pain. Key pain modulatory centers including the locus coeruleus, periaqueductal grey matter, and rostroventromedial medulla are vulnerable to TBI. Both the rationales and existing evidence for the use of monoamine reuptake inhibitors, CGRP antagonists, CXCR2 chemokine receptor antagonists, and interventional therapies will be presented. While consensus guidelines for the management of chronic post-traumatic TBI-related pain are lacking, several approaches to this clinically challenging situation deserve focused evaluation and may prove to be viable therapeutic options.
Collapse
Affiliation(s)
- QiLiang Chen
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University, School of Medicine, Stanford, CA, 94305, USA
| | - Vimala Bharadwaj
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University, School of Medicine, Stanford, CA, 94305, USA
| | - Karen-Amanda Irvine
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University, School of Medicine, Stanford, CA, 94305, USA; Anesthesiology Service, Veterans Affairs Palo Alto Health Care System, 3801 Miranda Ave (E4-220), Palo Alto, CA, 94304, USA
| | - J David Clark
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University, School of Medicine, Stanford, CA, 94305, USA; Anesthesiology Service, Veterans Affairs Palo Alto Health Care System, 3801 Miranda Ave (E4-220), Palo Alto, CA, 94304, USA.
| |
Collapse
|