scholarly journals Association between Chronic Pain and Alterations in the Mesolimbic Dopaminergic System

2020 ◽  
Vol 10 (10) ◽  
pp. 701
Author(s):  
Seoyon Yang ◽  
Mathieu Boudier-Revéret ◽  
Yoo Jin Choo ◽  
Min Cheol Chang

Chronic pain (pain lasting for >3 months) decreases patient quality of life and even occupational abilities. It can be controlled by treatment, but often persists even after management. To properly control pain, its underlying mechanisms must be determined. This review outlines the role of the mesolimbic dopaminergic system in chronic pain. The mesolimbic system, a neural circuit, delivers dopamine from the ventral tegmental area to neural structures such as the nucleus accumbens, prefrontal cortex, anterior cingulate cortex, and amygdala. It controls executive, affective, and motivational functions. Chronic pain patients suffer from low dopamine production and delivery in this system. The volumes of structures constituting the mesolimbic system are known to be decreased in such patients. Studies on administration of dopaminergic drugs to control chronic pain, with a focus on increasing low dopamine levels in the mesolimbic system, show that it is effective in patients with Parkinson’s disease, restless legs syndrome, fibromyalgia, dry mouth syndrome, lumbar radicular pain, and chronic back pain. However, very few studies have confirmed these effects, and dopaminergic drugs are not commonly used to treat the various diseases causing chronic pain. Thus, further studies are required to determine the effectiveness of such treatment for chronic pain.

1995 ◽  
Vol 26 (4) ◽  
pp. 21-25 ◽  
Author(s):  
Jane Boyer McGuigan

This study explored the applicability of Seligman's leamed helplessness theory to men receiving treatment for chronic back pain. Negative attributional style and depression scores for 112 men receiving treatment for chronic pain were obtained. Fifty-four men were receiving worker's compensation; fifty-eight were not. Participants voluntarily completed the Attributional Style Questionnaire, the Beck Depression Inventory, and a visual analogue scale measuring perceived ability to control pain. Demographic information was also obtained. Multivariate analysis of variance indicated that the groups did not differ in negative attributional style scores, but that they did differ in depression scores. No relationship was found between depression, negative attributional style, and perceived level of pain.


2020 ◽  
Vol 117 (18) ◽  
pp. 10015-10023 ◽  
Author(s):  
Meena M. Makary ◽  
Pablo Polosecki ◽  
Guillermo A. Cecchi ◽  
Ivan E. DeAraujo ◽  
Daniel S. Barron ◽  
...  

Chronic pain is a highly prevalent disease with poorly understood pathophysiology. In particular, the brain mechanisms mediating the transition from acute to chronic pain remain largely unknown. Here, we identify a subcortical signature of back pain. Specifically, subacute back pain patients who are at risk for developing chronic pain exhibit a smaller nucleus accumbens volume, which persists in the chronic phase, compared to healthy controls. The smaller accumbens volume was also observed in a separate cohort of chronic low-back pain patients and was associated with dynamic changes in functional connectivity. At baseline, subacute back pain patients showed altered local nucleus accumbens connectivity between putative shell and core, irrespective of the risk of transition to chronic pain. At follow-up, connectivity changes were observed between nucleus accumbens and rostral anterior cingulate cortex in the patients with persistent pain. Analysis of the power spectral density of nucleus accumbens resting-state activity in the subacute and chronic back pain patients revealed loss of power in the slow-5 frequency band (0.01 to 0.027 Hz) which developed only in the chronic phase of pain. This loss of power was reproducible across two cohorts of chronic low-back pain patients obtained from different sites and accurately classified chronic low-back pain patients in two additional independent datasets. Our results provide evidence that lower nucleus accumbens volume confers risk for developing chronic pain and altered nucleus accumbens activity is a signature of the state of chronic pain.


2020 ◽  
Vol 16 (3) ◽  
pp. 215-218
Author(s):  
Jonathan P. Eskander, MD, MBA ◽  
Junaid Spall, BS ◽  
Awais Spall, BA ◽  
Rinoo V. Shah, MD, MBA ◽  
Alan D. Kaye, MD, PhD

Objective: Two patient case reports are presented describing the use of cannabidiol (CBD) for the symptomatic relief of a lumbar compression fracture and in the mitigation of thoracic discomfort and dysesthesia secondary to a surgically resected meningioma.Discussion: CBD appears to have antisnociceptive and anti-inflammatory effects on opioid-naive patients with neuropathic and radicular pain. Of note, the patients in this case series used the same CBD cream: Baskin Essentials Body Wellness Cream (400 mg CBD per two oz.)Conclusion: Hemp-derived CBD in a transdermal cream provided significant symptom and pain relief for the patients described in this case series. Based on these results, we believe further investigation is warranted to see if CBD-containing products should have a more prominent role in the treatment of acute and chronic pain. 


2021 ◽  
Vol 17 ◽  
pp. 174480692199902
Author(s):  
Jing-Shan Lu ◽  
Qi-Yu Chen ◽  
Xiang Chen ◽  
Xu-Hui Li ◽  
Zhaoxiang Zhou ◽  
...  

Parkinson’s disease is the second most common neurodegenerative disorder after Alzheimer’s disease. Chronic pain is experienced by the vast majority of patients living with Parkinson’s disease. The degeneration of dopaminergic neuron acts as the essential mechanism of Parkinson’s disease in the midbrain dopaminergic pathway. The impairment of dopaminergic neurons leads to dysfunctions of the nociceptive system. Key cortical areas, such as the anterior cingulate cortex (ACC) and insular cortex (IC) that receive the dopaminergic projections are involved in pain transmission. Dopamine changes synaptic transmission via several pathway, for example the D2-adenly cyclase (AC)-cyclic AMP (cAMP)-protein kinase A (PKA) pathway and D1-G protein-coupled receptor kinase 2 (GRK2)-fragile X mental retardation protein (FMRP) pathway. The management of Parkinson’s disease-related pain implicates maintenance of stable level of dopaminergic drugs and analgesics, however a more selective drug targeting at key molecules in Parkinson’s disease-related pain remains to be investigated.


2021 ◽  
Vol 14 ◽  
Author(s):  
Zui Shen ◽  
Haiyan Zhang ◽  
Zemin Wu ◽  
Qiaoying He ◽  
Jinggen Liu ◽  
...  

Anxiety is a common comorbidity associated with chronic pain, which results in chronic pain complexification and difficulty in treatment. Electroacupuncture (EA) is commonly used to treat chronic pain and anxiety. However, the underlying mechanisms of the EA effect are largely unknown. Here, we showed that a circuitry underlying chronic pain induces anxiety disorders, and EA can treat them by regulating such circuitry. Using chemogenetic methods, we found that chemogenetic activation of the rostral anterior cingulate cortex (rACC) glutamatergic output to the thalamus induced anxiety disorders in control rats. Then, chemogenetic inhibition of the rACC-thalamus circuitry reduced anxiety-like behavior produced by intraplantar injection of the complete Freund’s adjuvant (CFA). In this study, we examined the effects of EA on a rat model of CFA-mediated anxiety-like behaviors and the related mechanisms. We found that chemogenetic activation of the rACC-thalamus circuitry effectively blocked the effects of EA on chronic pain-induced anxiety-like behaviors in CFA rats. These results demonstrate an underlying rACC-thalamus glutamatergic circuitry that regulates CFA-mediated anxiety-like behaviors. This study also provides a potential mechanistic explanation for EA treatment of anxiety caused by chronic pain.


2021 ◽  
Vol 5 ◽  
pp. 247054702110302
Author(s):  
Taylor D. Yeater ◽  
David J. Clark ◽  
Lorraine Hoyos ◽  
Pedro A. Valdes-Hernandez ◽  
Julio A. Peraza ◽  
...  

Background Autonomic dysregulation may lead to blunted sympathetic reactivity in chronic pain states. Autonomic responses are controlled by the central autonomic network (CAN). Little research has examined sympathetic reactivity and associations with brain CAN structures in the presence of chronic pain; thus, the present study aims to investigate how chronic pain influences sympathetic reactivity and associations with CAN brain region volumes. Methods Sympathetic reactivity was measured as change in skin conductance level (ΔSCL) between a resting reference period and walking periods for typical and complex walking tasks (obstacle and dual-task). Participants included 31 people with (n = 19) and without (n = 12) chronic musculoskeletal pain. Structural 3 T MRI was used to determine gray matter volume associations with ΔSCL in regions of the CAN (i.e., brainstem, amygdala, insula, and anterior cingulate cortex). Results ΔSCL varied across walking tasks (main effect p = 0.036), with lower ΔSCL in chronic pain participants compared to controls across trials 2 and 3 under the obstacle walking condition. ΔSCL during typical walking was associated with multiple CAN gray matter volumes, including brainstem, bilateral insula, amygdala, and right caudal anterior cingulate cortex (p’s < 0.05). The difference in ΔSCL from typical-to-obstacle walking were associated with volumes of the midbrain segment of the brainstem and anterior segment of the circular sulcus of the insula (p’s < 0.05), with no other significant associations. The difference in ΔSCL from typical-to-dual task walking was associated with the bilateral caudal anterior cingulate cortex, and left rostral cingulate cortex (p’s < 0.05). Conclusions Sympathetic reactivity is blunted during typical and complex walking tasks in persons with chronic pain. Additionally, blunted sympathetic reactivity is associated with CAN brain structure, with direction of association dependent on brain region. These results support the idea that chronic pain may negatively impact typical autonomic responses needed for walking performance via its potential impact on the brain.


2021 ◽  
Vol 17 ◽  
pp. 174480692199093
Author(s):  
Dan-jie Su ◽  
Long-fei Li ◽  
Sai-ying Wang ◽  
Qi Yang ◽  
Yu-jing Wu ◽  
...  

Chronic pain is highly prevalent worldwide and severely affects daily lives of patients and family members. Praeruptorin C (Pra-C) is a main active ingredient derived from Peucedanum praeruptorum Dunn, traditionally used as antibechic, anti-bronchitis and anti-hypertension drug. Here, we evaluated the effects of Pra-C in a chronic inflammatory pain mouse model induced by complete Freund’s adjuvant (CFA) injection. Pra-C (3 mg/kg) treatment for just 3 days after CFA challenge relieved CFA-induced mechanical allodynia and hindpaw edema in mice. In the anterior cingulate cortex (ACC), Pra-C treatment inhibited microglia activation and reduced levels of proinflammatory cytokines, TNF-α and IL-1β, and suppressed upregulation of glutamate receptors caused by CFA injection. In addition, Pra-C attenuated neuronal hyperexcitability in ACC of CFA-injected mice. In vitro studies confirmed the analgesic effect of Pra-C was due to its inhibitory ability on microglial activation. In conclusion, Pra-C administration had a certain effect on relieving chronic pain by inhibiting microglial activation, attenuating proinflammatory cytokine releasing and regulating excitatory synaptic proteins in the ACC of the CFA-injected mice.


Sign in / Sign up

Export Citation Format

Share Document