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Tinnirello A, Mazzoleni S, Santi C. Chronic Pain in the Elderly: Mechanisms and Distinctive Features. Biomolecules 2021; 11:biom11081256. [PMID: 34439922 PMCID: PMC8391112 DOI: 10.3390/biom11081256] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 08/17/2021] [Accepted: 08/20/2021] [Indexed: 12/22/2022] Open
Abstract
Background: Chronic pain is a major issue affecting more than 50% of the older population and up to 80% of nursing homes residents. Research on pain in the elderly focuses mainly on the development of clinical tools to assess pain in patients with dementia and cognitive impairment or on the efficacy and tolerability of medications. In this review, we searched for evidence of specific pain mechanisms or modifications in pain signals processing either at the cellular level or in the central nervous system. Methods: Narrative review. Results: Investigation on pain sensitivity led to conflicting results, with some studies indicating a modest decrease in age-related pain sensitivity, while other researchers found a reduced pain threshold for pressure stimuli. Areas of the brain involved in pain perception and analgesia are susceptible to pathological changes such as gliosis and neuronal death and the effectiveness of descending pain inhibitory mechanisms, particularly their endogenous opioid component, also appears to deteriorate with advancing age. Hyperalgesia is more common at older age and recovery from peripheral nerve injury appears to be delayed. In addition, peripheral nociceptors may contribute minimally to pain sensation at either acute or chronic time points in aged populations. Conclusions: Elderly subjects appear to be more susceptible to prolonged pain development, and medications acting on peripheral sensitization are less efficient. Pathologic changes in the central nervous system are responsible for different pain processing and response to treatment. Specific guidelines focusing on specific pathophysiological changes in the elderly are needed to ensure adequate treatment of chronic pain conditions.
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Affiliation(s)
- Andrea Tinnirello
- Anesthesiology and Pain Medicine Department, ASST Franciacorta, Ospedale di Iseo, 25049 Iseo, Italy
- Correspondence: ; Tel.: +39-030-7103-395
| | - Silvia Mazzoleni
- Second Division of Anesthesiology, Intensive Care & Emergency Medicine, University of Brescia at Spedali Civili Hospital, Piazzale Spedali Civili 1, 25100 Brescia, Italy; (S.M.); (C.S.)
| | - Carola Santi
- Second Division of Anesthesiology, Intensive Care & Emergency Medicine, University of Brescia at Spedali Civili Hospital, Piazzale Spedali Civili 1, 25100 Brescia, Italy; (S.M.); (C.S.)
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Mantyh PW. Mechanisms that drive bone pain across the lifespan. Br J Clin Pharmacol 2018; 85:1103-1113. [PMID: 30357885 DOI: 10.1111/bcp.13801] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 10/18/2018] [Accepted: 10/19/2018] [Indexed: 02/06/2023] Open
Abstract
Disorders of the skeleton are frequently accompanied by bone pain and a decline in the functional status of the patient. Bone pain occurs following a variety of injuries and diseases including bone fracture, osteoarthritis, low back pain, orthopedic surgery, fibrous dysplasia, rare bone diseases, sickle cell disease and bone cancer. In the past 2 decades, significant progress has been made in understanding the unique population of sensory and sympathetic nerves that innervate bone and the mechanisms that drive bone pain. Following physical injury of bone, mechanotranducers expressed by sensory nerve fibres that innervate bone are activated and sensitized so that even normally non-noxious loading or movement of bone is now being perceived as noxious. Injury of the bone also causes release of factors that; directly excite and sensitize sensory nerve fibres, upregulate proalgesic neurotransmitters, receptors and ion channels expressed by sensory neurons, induce ectopic sprouting of sensory and sympathetic nerve fibres resulting in a hyper-innervation of bone, and central sensitization in the brain that amplifies pain. Many of these mechanisms appear to be involved in driving both nonmalignant and malignant bone pain. Results from human clinical trials suggest that mechanism-based therapies that attenuate one type of bone pain are often effective in attenuating pain in other seemingly unrelated bone diseases. Understanding the specific mechanisms that drive bone pain in different diseases and developing mechanism-based therapies to control this pain has the potential to fundamentally change the quality of life and functional status of patients suffering from bone pain.
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Affiliation(s)
- Patrick W Mantyh
- Department of Pharmacology, University of Arizona, Tucson, AZ, USA.,Cancer Center, University of Arizona, Tucson, AZ, USA
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Ahn JH, Shin MC, Park JH, Kim IH, Lee JC, Yan BC, Hwang IK, Moon SM, Ahn JY, Ohk TG, Lee TH, Cho JH, Shin HC, Won MH. Increased immunoreactivity of c‑Fos in the spinal cord of the aged mouse and dog. Mol Med Rep 2014; 11:1043-8. [PMID: 25351722 DOI: 10.3892/mmr.2014.2800] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 07/22/2014] [Indexed: 11/06/2022] Open
Abstract
Expression of c‑Fos in the spinal cord following nociceptive stimulation is considered to be a neurotoxic biomarker. In the present study, the immunoreactivity of c‑Fos in the spinal cord was compared between young adult (2‑3 years in dogs and 6 months in mice) and aged (10‑12 years in dogs and 24 months in mice) Beagle dogs and C57BL/6J mice. In addition, changes to neuronal distribution and damage to the spinal cord were also investigated. There were no significant differences in neuronal loss or degeneration of the spinal neurons observed in either the aged dogs or mice. Weak c‑Fos immunoreactivity was observed in the spinal neurons of the young adult animals; however, c‑Fos immunoreactivity was markedly increased in the nuclei of spinal neurons in the aged dogs and mice, as compared with that of the young adults. In conclusion, c‑Fos immunoreactivity was significantly increased without any accompanying neuronal loss in the aged spinal cord of mice and dogs, as compared with the spinal cords of the young adult animals.
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Affiliation(s)
- Ji Hyeon Ahn
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 200‑701, Republic of Korea
| | - Myoung Chul Shin
- Department of Emergency Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon 200‑701, Republic of Korea
| | - Joon Ha Park
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 200‑701, Republic of Korea
| | - In Hye Kim
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 200‑701, Republic of Korea
| | - Jae-Chul Lee
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 200‑701, Republic of Korea
| | - Bing Chun Yan
- Institute of Integrative Traditional and Western Medicine, Medical College, Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - In Koo Hwang
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, Seoul National University, Seoul 151‑742, Republic of Korea
| | - Seung Myung Moon
- Department of Neurosurgery, Dongtan Sacred Heart Hospital, College of Medicine, Hallym University, Hwaseong, Gyeonggi 445‑170, Republic of Korea
| | - Ji Yun Ahn
- Department of Emergency Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon 200‑701, Republic of Korea
| | - Taek Geun Ohk
- Department of Emergency Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon 200‑701, Republic of Korea
| | - Tae Hun Lee
- Department of Emergency Medicine, Chuncheon Sacred Heart Hospital, College of Medicine, Hallym University, Chuncheon, Gangwon 200‑702, Republic of Korea
| | - Jun Hwi Cho
- Department of Emergency Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon 200‑701, Republic of Korea
| | - Hyung-Cheul Shin
- Department of Physiology, College of Medicine, Hallym University, Chuncheon, Gangwon 200‑702, Republic of Korea
| | - Moo-Ho Won
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 200‑701, Republic of Korea
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Vitamin D deficiency leads to sensory and sympathetic denervation of the rat synovium. Neuroscience 2014; 279:77-93. [PMID: 25193239 DOI: 10.1016/j.neuroscience.2014.08.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 08/15/2014] [Accepted: 08/21/2014] [Indexed: 12/20/2022]
Abstract
Vitamin D deficiency is associated with increased susceptibility to inflammatory arthritis. Sensory and sympathetic synovial nerves are critical to the development of inflammatory arthritis and spontaneously degenerate in the early phases of disease. These nerves contain vitamin D receptors and vitamin D influences nerve growth and neurotrophin expression. We therefore examined the density of synovial nerves and neurotrophin-containing cells in vitamin D-deficient rats. Seven-week-old Sprague-Dawley rats were fed either control or vitamin D-deficient diets for 4weeks. Knee synovium sections extending from the patella to the meniscus were immunostained for total nerves, myelinated and unmyelinated nerves, sympathetic nerves, peptidergic and non-peptidergic sensory nerves, and neurotrophins and immune cell markers. In control rats, intimal innervation by unmyelinated sensory fibers was denser than subintimal innervation. In contrast, sympathetic innervation was confined to the subintima. Many sensory axons contained markers for both peptidergic and non-peptidergic nerves. Nerve growth factor (NGF) was primarily expressed by intimal CD163-negative type B synoviocytes, while neurturin, a ligand selective for non-peptidergic sensory neurons, was expressed by synovial mast cells. In vitamin D-deficient rats, there were significant reductions in sensory nerves in the intima and sympathetic nerves in the subintima. While there was no significant change in NGF-immunoreactivity, the number of neurturin-expressing mast cells was significantly reduced in the intima, suggesting that intimal reductions in sensory nerves may be related to reductions in neurturin. Vitamin D deficiency therefore may increase susceptibility to inflammatory arthritis by depleting sensory and sympathetic synovial nerves as a result of reduced synovial neurotrophin content.
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Liu J, Li G, Peng H, Tu G, Kong F, Liu S, Gao Y, Xu H, Qiu S, Fan B, Zhu Q, Yu S, Zheng C, Wu B, Peng L, Song M, Wu Q, Li G, Liang S. Sensory-sympathetic coupling in superior cervical ganglia after myocardial ischemic injury facilitates sympathoexcitatory action via P2X7 receptor. Purinergic Signal 2013; 9:463-79. [PMID: 23754120 PMCID: PMC3757147 DOI: 10.1007/s11302-013-9367-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Accepted: 05/13/2013] [Indexed: 12/17/2022] Open
Abstract
P2X receptors participate in cardiovascular regulation and disease. After myocardial ischemic injury, sensory-sympathetic coupling between rat cervical DRG nerves and superior cervical ganglia (SCG) facilitated sympathoexcitatory action via P2X7 receptor. The results showed that after myocardial ischemic injury, the systolic blood pressure, heart rate, serum cardiac enzymes, IL-6, and TNF-α were increased, while the levels of P2X7 mRNA and protein in SCG were also upregulated. However, these alterations diminished after treatment of myocardial ischemic (MI) rats with the P2X7 antagonist oxATP. After siRNA P2X7 in MI rats, the systolic blood pressure, heart rate, serum cardiac enzymes, the expression levels of the satellite glial cell (SGC) or P2X7 were significantly lower than those in MI group. The phosphorylation of ERK 1/2 in SCG participated in the molecular mechanism of the sympathoexcitatory action induced by the myocardial ischemic injury. Retrograde tracing test revealed the sprouting of CGRP or SP sensory nerves (the markers of sensory afferent fibers) from DRG to SCG neurons. The upregulated P2X7 receptor promoted the activation of SGCs in SCG, resulting in the formation of sensory-sympathetic coupling which facilitated the sympathoexcitatory action. P2X7 antagonist oxATP could inhibit the activation of SGCs and interrupt the formation of sensory-sympathetic coupling in SCG after the myocardial ischemic injury. Our findings may benefit the treatment of coronary heart disease and other cardiovascular diseases.
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Affiliation(s)
- Jun Liu
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Guilin Li
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Haiying Peng
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Guihua Tu
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Fanjun Kong
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Shuangmei Liu
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Yun Gao
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Hong Xu
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Shuyi Qiu
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Bo Fan
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Qicheng Zhu
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Shicheng Yu
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Chaoran Zheng
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Bing Wu
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Lichao Peng
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Miaomiao Song
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Qin Wu
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Guodong Li
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
| | - Shangdong Liang
- />Department of Physiology, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
- />Key Laboratory of Basic Medicine, Medical College of Nanchang University, Nanchang, Jiangxi 330006 People’s Republic of China
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Tu G, Li G, Peng H, Hu J, Liu J, Kong F, Liu S, Gao Y, Xu C, Xu X, Qiu S, Fan B, Zhu Q, Yu S, Zheng C, Wu B, Peng L, Song M, Wu Q, Liang S. P2X(7) inhibition in stellate ganglia prevents the increased sympathoexcitatory reflex via sensory-sympathetic coupling induced by myocardial ischemic injury. Brain Res Bull 2013; 96:71-85. [PMID: 23688519 DOI: 10.1016/j.brainresbull.2013.05.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 05/08/2013] [Accepted: 05/09/2013] [Indexed: 12/11/2022]
Abstract
Purinergic signaling has been found to participate in the regulation of cardiovascular function. In this study, using a rat myocardial ischemic injury model, the sympathoexcitatory reflex mediated by P2X7 receptor via sensory-sympathetic coupling between cervical dorsal root ganglia (DRG) nerves and stellate ganglia (SG) nerves was explored. Our results showed that the systolic blood pressure, heart rate, serum cardiac enzymes concentrations, interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) concentrations were increased, and the expression levels of P2X7 mRNA and protein in DRG and SG were up-regulated after myocardial ischemic injury. Administration of brilliant blue G (BBG), a selective P2X7 antagonist, decreased the elevation of systolic blood pressure, heart rate, serum cardiac enzyme, IL-6 and TNF-α, and inhibited the up-regulated expression of P2X7 mRNA and protein in DRG and SG after myocardial ischemic injury. Retrograde tracing test showed that there were calcitonin gene-related peptide sensory nerves and substance P sensory nerves sprouting from DRG to SG, which played an important role in the development of myocardial ischemic injury. The up-regulated P2X7 receptor expression levels on the surface membrane of satellite glial cells contributed to the activation of sensory-sympathetic coupling, which in turn facilitated the sympathoexcitatory reflex. BBG can inhibit the activation of satellite glial cells and interrupt the generation of sensory-sympathetic coupling in the cervical sympathetic ganglia after the myocardial ischemic injury. Taken together, these findings may provide a new therapeutic approach for treating coronary heart disease, hypertension and other cardiovascular diseases.
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Affiliation(s)
- Guihua Tu
- Department of Physiology, Information Engineering College of Nanchang University, Nanchang, Jiangxi 330006, PR China
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Li Y, Li H, Liu G, Liu Z. Effects of neuregulin-1β on growth-associated protein 43 expression in dorsal root ganglion neurons with excitotoxicity induced by glutamate in vitro. Neurosci Res 2013; 76:22-30. [PMID: 23524246 DOI: 10.1016/j.neures.2013.02.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2012] [Revised: 02/18/2013] [Accepted: 02/19/2013] [Indexed: 11/19/2022]
Abstract
Neuregulin-1β (NRG-1β) is a growth factor with potent neuroprotective capacity. Growth-associated protein 43 (GAP-43) is expressed in dorsal root ganglion (DRG) neurons and an indicator of neuronal survival in vitro. The purpose of present study is to evaluate the effects of NRG-1β on GAP-43 expression in DRG neurons with excitotoxicity induced by glutamate (Glu) in vitro. The phosphatidylinositol 3-kinase (PI3K)/Akt and extracellular signal-regulated protein kinase 1/2 (ERK1/2) signaling pathways involved in these effects were also determined. Embryonic rat DRG neurons were treated with Glu in the absence or presence of NRG-1β and PI3K inhibitor LY294002 and/or ERK1/2 inhibitor PD98059. After that, GAP-43 mRNA and GAP-43 protein levels were analyzed by real time-PCR and western blot assay, respectively. GAP-43 expression in situ was determined by immunofluorescent labeling. The results showed that the decreased GAP-43 levels induced by Glu could be partially reversed by the presence of NRG-1β. Inhibitors (LY294002, PD98059) either alone or in combination blocked the effects of NRG-1β. These data provide new insights of the actions of NRG-1β in sensory neurons.
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Affiliation(s)
- Yunfeng Li
- Faculty of Clinical Medicine, Shandong University School of Medicine, Jinan 250012, China
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Csati A, Tajti J, Tuka B, Edvinsson L, Warfvinge K. Calcitonin gene-related peptide and its receptor components in the human sphenopalatine ganglion — Interaction with the sensory system. Brain Res 2012; 1435:29-39. [DOI: 10.1016/j.brainres.2011.11.058] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Revised: 10/26/2011] [Accepted: 11/24/2011] [Indexed: 11/29/2022]
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Im HJ, Li X, Muddasani P, Kim GH, Davis F, Rangan J, Forsyth CB, Ellman M, Thonar EJMA. Basic fibroblast growth factor accelerates matrix degradation via a neuro-endocrine pathway in human adult articular chondrocytes. J Cell Physiol 2008; 215:452-63. [PMID: 17960584 DOI: 10.1002/jcp.21317] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Pain-related neuropeptides released from synovial fibroblasts, such as substance P, have been implicated in joint destruction. Substance P-induced inflammatory processes are mediated via signaling through a G-protein-coupled receptor, that is, neurokinin-1 tachykinin receptor (NK(1)-R). We determined the pathophysiological link between substance P and its receptor in human adult articular cartilage homeostasis. We further examined if catabolic growth factors such as basic fibroblast growth factor (bFGF or FGF-2) or IL-1beta accelerate matrix degradation via a neural pathway upregulation of substance P and NK(1)-R. We show here that substance P stimulates the production of cartilage-degrading enzymes, such as matrix metalloproteinase-13 (MMP-13), and suppresses proteoglycan deposition in human adult articular chondrocytes via NK(1)-R. Furthermore, we have demonstrated that substance P negates proteoglycan stimulation promoted by bone morphogenetic protein-7, suggesting the dual role of substance P as both a pro-catabolic and anti-anabolic mediator of cartilage homeostasis. We report that bFGF-mediated stimulation of substance P and its receptor NK(1)-R is, in part, through an IL-1beta-dependent pathway.
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Affiliation(s)
- Hee-Jeong Im
- Department of Biochemistry, Rush University Medical Center, Cohn Research BD, Chicago, Illinois 60612, USA.
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Gibson SJ, Farrell M. A Review of Age Differences in the Neurophysiology of Nociception and the Perceptual Experience of Pain. Clin J Pain 2004; 20:227-39. [PMID: 15218407 DOI: 10.1097/00002508-200407000-00004] [Citation(s) in RCA: 259] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To better understand the nature of age differences in pain and nociception with the aging of the worlds' population. METHODS The evidence from numerous neurophysiologic and psychological studies suggest a small, but demonstrable age-related impairment in the early warning functions of pain. The increase in pain perception threshold and the widespread change in the structure and function of peripheral and CNS nociceptive pathways may place the older person at greater risk of injury. Moreover, the reduced efficacy of endogenous analgesic systems, a decreased tolerance of pain and the slower resolution of postinjury hyperalgesia may make it more difficult for the older adult to cope, once injury has occurred. RESULTS These age-related changes may be best conceptualized as a reduced capacity in the functional reserve of the pain system, at both ends of the intensity spectrum. DISCUSSION The clinical implications are obvious; older persons are likely to be especially vulnerable to the negative impacts of pain and pain associated events.
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Affiliation(s)
- Stephen J Gibson
- Department of Medicine, University of Melbourne, Victoria, Australia.
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