neuropeptide-y and Fibromyalgia

Orofacial pain frequently originates from pathologic conditions in the masticatory muscles or temporomandibular joints (TMJs). The mediators and mechanisms that monitor pain and inflammation, centrally or peripherally, are of great interest in the search for new treatment modalities. The neuropeptides substance P (SP), calcitonin gene-related peptide (CGRP), and neuropeptide Y (NPY) have all been found at high levels in the synovial fluid of arthritic TMJs in association with spontaneous pain, while serotonin (5-HT) has been found in association with hyperalgesia/allodynia of the TMJ. Interleukin-1 beta (IL-1 beta) and tumor necrosis factor alpha (TNF alpha) have been found in arthritic TMJs, but not in healthy TMJs, in association with hyperalgesia/allodynia of the TMJ as well as spontaneous pain. Anterior open bite, which may be a clinical sign of TMJ destruction, has been found in association with high levels of CGRP, NPY, and IL-1 beta in the synovial fluid of the TMJ. Interleukin-1 beta has also been related to radiographic signs of joint destruction. Prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) are both present in the arthritic TMJ, and PGE2 has been shown to be associated with hyperalgesia/allodynia of the TMJ. Very little is known about pain and inflammatory mediators in muscles. However, we know that 5-HT and PGE2 are involved in the development of pain and hyperalgesia/allodynia of the masseter muscle in patients with fibromyalgia, whereas local myalgia (myofascial pain) seems to be modulated by other, as yet unknown mediators. Interaction between the peripheral nervous system (sensory and sympathetic nerves), the immune system, and local cells is probably of great importance for the modulation of pain and inflammation in the TMJ and orofacial musculature.

Topics: Arthritis; Calcitonin Gene-Related Peptide; Dinoprostone; Facial Pain; Fibromyalgia; Humans; Hyperalgesia; Inflammation Mediators; Interleukin-1; Leukotriene B4; Masseter Muscle; Neuroimmunomodulation; Neuropeptide Y; Neuropeptides; Neurosecretory Systems; Open Bite; Serotonin; Substance P; Synovial Fluid; Temporomandibular Joint Disorders; Tumor Necrosis Factor-alpha

Neuropeptide Y is associated with stress in animal and human laboratory studies. However, data from clinical studies are scarce and no clinical longitudinal studies have been published. The aim of this clinical study was to assess the possible association between changes in the levels of pain, depression, and stress measures, on the one hand, and plasma neuropeptide Y levels, on the other.. Forty-four women with the fibromyalgia syndrome were exposed to a Cognitive Behavioral Therapy intervention. Levels of the plasma neuropeptide Y as well as pain, depression, and stress measures were obtained at the start and at the end of the intervention, and after a further six month follow-up. Based on these data, a before-and-after analysis was performed.. Almost all measures of pain, depression, and stress improved during the study; specifically, variables measuring life control (coping), depression, and stress-related time urgency improved significantly. Moreover, during the same time period, the mean plasma neuropeptide Y level was reduced from 93.2 ± 38.8 fmol/mL before the Cognitive Behavioral Therapy to 75.6 ± 42.9 fmol/mL (p<0.001) at the end of the study.. After exposure to a Cognitive Behavioral Therapy intervention, levels of most of the pain, depression, and stress measures improved, half of them significantly, as did the levels of neuropeptide Y. This circumstance indicates a possible functional relationship between pain-depression-stress and neuropeptide Y.

Topics: Adaptation, Psychological; Female; Fibromyalgia; Humans; Longitudinal Studies; Neuropeptide Y; Pain

Smoking deregulates neuroendocrine responses to pain supporting production of neuropeptide Y (NpY) by direct stimulation of nicotinic receptors or by inhibiting adipokine leptin. Present study addressed the effect of cigarette smoking on adipokines and pain parameters, in 62 women with fibromyalgia (FM) pain syndrome with unknown etiology. Pain was characterized by a visual analogue scale, tender point (TP) counts, pressure pain threshold, and neuroendocrine markers NpY and substance P (sP). Levels of IGF-1, leptin, resistin, visfatin, and adiponectin were measured in blood and cerebrospinal fluid. Current smokers (n = 18) had lower levels of leptin compared to ex-smokers (n = 25, P = 0.002), while the expected NpY increase was absent in FM patients. In smokers, this was transcribed in higher VAS-pain (P = 0.04) and TP count (P = 0.03), lower pain threshold (P = 0.01), since NpY levels were directly related to the pain threshold (rho = 0.414) and inversely related to TP counts (rho = -0.375). This study shows that patients with FM have no increase of NpY levels in response to smoking despite the low levels of leptin. Deregulation of the balance between leptin and neuropeptide Y may be one of the essential mechanisms of chronic pain in FM.

Topics: Adult; Female; Fibromyalgia; Humans; Leptin; Middle Aged; Neuropeptide Y; Pain; Smoking

Fibromyalgia (FM) is thought to occur because of the combination of interactions among neurotransmitters, such as neuropeptide Y (NPY), stressors, hormones, cytokines, and both the immune and sympathetic nervous systems. The aim of this study was to evaluate serum concentrations of cytokines, antipolymer antibodies (APA), and NPY in 51 patients with FM, 25 with tension-type headache (TTH), and 15 healthy controls. Serum concentrations of eight different cytokines, APA and NPY, were measured. Interleukin (IL)-1RA, IL-6, IL-10, and tumor necrosis factor-alpha were higher in serum of FM patients compared with TTH patients and a significant correlation between IL-10 and Fibromyalgia Impact Questionnaire score was observed. There was a significant difference between FM and TTH versus controls in NPY levels, but not in APA levels. Cytokines and NPY take part in pain modulation and even if they are altered in FM they cannot be considered as measurable biomarkers of disease.

Topics: Adult; Aged; Antibodies; Case-Control Studies; Cytokines; Female; Fibromyalgia; Humans; Interviews as Topic; Male; Middle Aged; Neuropeptide Y; Pain; Surveys and Questionnaires; Syndrome; Tension-Type Headache

Autonomic nervous system dysfunction observed in fibromyalgia, characterized without exception by a sympathetic hyperactivity and hyporeactivity, has been reported. However, several studies demonstrated reduced levels of norepinephrine and neuropeptide Y at rest and after tilt table in some patients, which was improved by beta-stimulating agents. These findings support heterogeneity in fibromyalgia-associated dysautonomia. Fibromyalgia could be a generalized sympathetic dystrophy since both conditions are activated by trauma and partly linked to sympathetic mechanisms. Yet they differ on several points: hormonal and neurochemical abnormalities are observed in fibromyalgia whereas activation by peripheral trauma and hyperosteolysis are observed in reflex sympathetic dystrophy.

Topics: Autonomic Nervous System Diseases; Fibromyalgia; Humans; Neuropeptide Y; Norepinephrine; Reflex Sympathetic Dystrophy; Tilt-Table Test

To examine basal and stimulated hypothalamic-pituitary-adrenal (HPA) axis and related hormone levels, including adrenocorticotropin (ACTH), cortisol, arginine vasopressin (AVP), and neuropeptide Y (NPY), in patients with fibromyalgia (FM).. Basal and ovine corticotropin-releasing hormone (oCRH)-stimulated HPA axis function were assessed in 12 patients with FM and in age- and sex-matched normal subjects. Basal plasma AVP levels and AVP release after postural change were assessed, and plasma NPY levels were measured in the same samples.. Patients with FM had low 24-hour urinary free cortisol, but normal peak and elevated trough plasma cortisol levels, compared with normal subjects. The net integrated ACTH response to oCRH in FM was not significantly different from that in normal subjects, but tended toward an exaggerated response. There was a significant decrease in net integrated cortisol response to oCRH in FM patients, indicating adrenal hyporesponsiveness. AVP levels were not significantly different between FM patients and control subjects, but variability was greater among the FM patients. Plasma NPY levels were significantly lower in FM patients than in normal subjects.. These data support the view that HPA axis function is perturbed in patients with FM. Further study is required to ascertain the cause of HPA axis perturbations and their relationship to symptoms in patients with FM.

Topics: Adrenocorticotropic Hormone; Adult; Arginine; Arginine Vasopressin; Corticotropin-Releasing Hormone; Female; Fibromyalgia; Humans; Hydrocortisone; Hypothalamo-Hypophyseal System; Middle Aged; Neuropeptide Y; Pituitary-Adrenal System