Low plasma levels of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNFalpha), and vascular endothelial growth factor (VEGF) in patients with alpha1-antitrypsin deficiency-related fibromyalgia

Serum VEGF and CGRP Biomarkers: Relationships with Pain Intensity, Electric Pain, Pressure Pain Threshold, and Clinical Symptoms in Fibromyalgia-An Observational Study

Fibromyalgia (FM) is a multifactorial syndrome, mainly characterized by chronic widespread pain, whose physiopathology is yet to be determined. Reliable biomarkers for FM and how they are associated with the symptomatology have not yet been identified. We aimed to examine the relationships among serum vascular endothelial growth factor (VEGF) and calcitonin gene-related peptide (CGRP) levels with clinical manifestations and pain-related variables in women with FM. We conducted an observational case study with forty-seven women diagnosed with FM. Serum VEGF and CGRP levels were spectrophotometrically analyzed. We used questionnaires to measure the impact of FM and the degree of central sensitization, fatigue, and anxiety. We also assessed pain intensity, electric pain threshold and magnitude, and pressure pain threshold (PPT) in tender points. The linear regression analysis adjusting for age, menopause status, and body mass index showed that serum VEGF levels were significantly associated with the PPTs of non-dominant trapezius (β = 153.418; p = 0.033), non-dominant second metacarpal (β = 174.676; p = 0.008) and dominant tibialis anterior (β = 115.080; p = 0.049) in women with FM. We found no association between serum CGRP levels and the variables measured (p ≥ 0.152). Our results suggest that VEGF may be related to pain processing in patients with FM.

Associations among serum VEGF and CGRP levels with the peripheral vascular blood flow of the skin of the hands in women with Fibromyalgia

BACKGROUND

Fibromyalgia (FM) is a long-term condition of unknown physiopathology, whose hallmark symptoms are diffuse musculoskeletal chronic pain and fatigue.

OBJECTIVES

We aimed to analyze the associations among serum vascular endothelial growth factor (VEGF) and calcitonin gene-related peptide (CGRP) levels with the peripheral temperature of the skin of both hands and the core body temperature in patients with FM and healthy controls.

METHODS

We conducted a case-control observational study with fifty-three women diagnosed with FM and twenty-four healthy women. VEGF and CGRP levels were spectrophotometrically analyzed in serum by enzyme-linked immunosorbent assay. We used an infrared thermography camera to assess the peripheral temperature of the skin of the dorsal thumb, index, middle, ring, and pinkie fingertips and dorsal centre as well as the palm thumb, index, middle, ring, and pinkie fingertips, palm centre and thenar and hypothenar eminences of both hands and an infrared thermographic scanner to record the tympanic membrane and axillary temperature.

RESULTS

Linear regression analysis adjusting for age, menopause status, and body mass index showed that serum VEGF levels were positively associated with the maximum (β = 65.942, 95% CI [4.100,127.784], p = 0.037), minimum (β = 59.216, 95% CI [1.455,116.976], p = 0.045), and mean (β = 66.923, 95% CI [3.142,130.705], p = 0.040) temperature of the thenar eminence of the non-dominant hand, as well as with the maximum temperature of the hypothenar eminence of the non-dominant hand (β = 63.607, 95% CI [3.468,123.747], p = 0.039) in women diagnosed with FM.

CONCLUSIONS

Mild associations were observed between serum VEGF levels and the peripheral temperature of the skin in hand areas in patients with FM; therefore, it is not possible to establish a clear relationship between this vasoactive molecule and vasodilation of the hands in these patients.

Calcitonin Gene-Related Peptide, Vascular Endothelial Growth Factor, and Clinical Manifestations in Women With Fibromyalgia

BACKGROUND

Fibromyalgia is a complex illness to diagnose and treat, which significantly impairs patients' quality of life.

OBJECTIVES

The study aims were to compare levels of calcitonin gene-related peptide and vascular endothelial growth factor between patients with fibromyalgia and healthy controls and to examine their relationship with the main clinical manifestations of fibromyalgia.

METHODS

This case-control study included 42 women diagnosed with fibromyalgia and 22 healthy women. Serum calcitonin gene-related peptide and vascular endothelial growth factor levels were spectrophotometrically analyzed by enzyme-linked immunosorbent assay. Clinical manifestations were assessed by means of self-administered questionnaires, including functional capacity in daily living activities, musculoskeletal pain, fatigue, anxiety, and sleep quality. The predictive value of these parameters in fibromyalgia was determined by receiver operating characteristic curve analysis.

RESULTS

Serum calcitonin gene-related peptide levels significantly increased in the fibromyalgia group in comparison to the control group. However, there were no significant differences in vascular endothelial growth factor levels between patients and controls. No significant correlations were found between calcitonin gene-related peptide and vascular endothelial growth factor and the symptoms analyzed.

DISCUSSION

Serum calcitonin gene-related peptide levels were dysregulated in women with fibromyalgia and may be a reliable parameter to help diagnose this complex syndrome.

Potential role of blood biomarkers in patients with fibromyalgia: a systematic review with meta-analysis

ABSTRACT

Fibromyalgia (FM) is a complex chronic pain condition. Its symptoms are nonspecific, and to date, no objective test exists to confirm FM diagnosis. Potential objective measures include the circulating levels of blood biomarkers. This systematic review and meta-analysis aim to review studies assessing blood biomarkers' levels in patients with FM compared with healthy controls. We systematically searched the PubMed, MEDLINE, EMBASE, and PsycINFO databases. Fifty-four studies reporting the levels of biomarkers in blood in patients with FM were included. Data were extracted, and the methodological quality was assessed independently by 2 authors. The methodological quality of 9 studies (17%) was low. The results of most studies were not directly comparable given differences in methods and investigated target immune mediators. Thus, data from 40 studies only were meta-analyzed using a random-effects model. The meta-analysis showed that patients with FM had significantly lower levels of interleukin-1 β and higher levels of IL-6, IL-8, tumor necrosis factor-alpha, interferon gamma, C-reactive protein, and brain-derived neurotrophic factor compared with healthy controls. Nevertheless, this systematic literature review and meta-analysis could not support the notion that these blood biomarkers are specific biomarkers of FM. Our literature review, however, revealed that these same individual biomarkers may have the potential role of identifying underlying pathologies or other conditions that often coexist with FM. Future research is needed to evaluate the potential clinical value for these biomarkers while controlling for the various confounding variables.

Is fibromyalgia associated with a unique cytokine profile? A systematic review and meta-analysis

Objectives

The aetiology of primary chronic pain syndromes (CPS) is highly disputed. We performed a systematic review and meta-analysis aiming to assess differences in circulating cytokine levels in patients with diffuse CPS (fibromyalgia) vs healthy controls (HC).

Methods

Human studies published in English from the PubMed, MEDLINE/Scopus and Cochrane databases were systematically searched from inception up to January 2020. We included full text cross-sectional or longitudinal studies with baseline cytokine measurements, reporting differences in circulating cytokine levels between fibromyalgia patients and HC. Random-effects meta-analysis models were used to report pooled effects and 95% CIs. This study is registered with PROSPERO (CRD42020193774).

Results

Our initial search yielded 324 papers and identified 29 studies (2458 participants) eligible for systematic review and 22 studies (1772 participants) suitable for meta-analysis. The systematic analysis revealed reproducible findings supporting different trends of cytokine levels when fibromyalgia patients were compared with HC, while the chemokine eotaxin, was consistently raised in fibromyalgia. Meta-analysis showed significantly increased TNF-α [standardized mean difference (SMD) = 0.36, 95% CI: 0.12, 0.60, P = 0.0034; I² = 71%, Q²P = 0.0002], IL-6 (SMD = 0.15, 95% CI: 0.003, 0.29, P = 0.045; I² = 39%, Q²P = 0.059), IL-8 (SMD = 0.26, 95% CI: 0.05, 0.47, P = 0.01; I² = 61%, Q²P = 0.005) and IL-10 (SMD = 0.61, 95% CI: 0.34, 0.89, P < 0.001; I² = 10%, Q²P = 0.34) in fibromyalgia patients compared with HC.

Conclusion

We found evidence of significant differences in the peripheral blood cytokine profiles of fibromyalgia patients compared with HC. However, the distinctive profile associated with fibromyalgia includes both pro-inflammatory (TNF-α, IL-6, IL-8) and anti-inflammatory (IL-10) cytokines in pooled analysis, as well as chemokine (eotaxin) signatures. Further research is required to elucidate the role of cytokines in fibromyalgia.

A theoretical framework to improve the construct for chronic pain disorders using fibromyalgia as an example

Fibromyalgia (FM) is a frequent, complex condition of chronic musculoskeletal pain with no evidence for biological correlates. For this reason, despite many efforts from the medical community, its construct still appears ill defined. Promising candidate biomarkers are critically reviewed. A research agenda is proposed for developing a clearer construct of FM. The ideal theoretical framework is one of overcoming the illness–disease dichotomy and considering reciprocal interactions between biology and behaviour. This approach may foster research in other fields of pain medicine and of medicine in general.

MCP-2/CCL8 Level Associated With Suicidal Ideation in Elderly Men With Major Depression

OBJECTIVES

We compared serum levels of chemokines between male elders with major depressive disorder (MDD) and healthy controls, verifying whether any difference exists in the levels of these mediators between those with and without current suicidal ideation (SI).

METHODS

We enrolled 145 male elders aged 65 or older and analyzed 40 chemokines in patients with MDD with SI (n = 24) and without SI (n = 23), as well as healthy controls (n = 98).

RESULTS

The patients with MDD with SI presented higher levels of MCP-2/CCL8 (p < 0.001) compared with the patients with MDD without SI and the healthy controls.

CONCLUSIONS

Current findings suggest a potential role of MCP-2/CCL8 in suicidality among elderly males with depression.

Serum Vascular Endothelial Growth Factor and Vascular Endothelial Growth Factor Receptor-1 Levels in Patients With Fibromyalgia Syndrome

Objectives

This study aims to compare the serum vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor-1 (VEGFR-1) levels between patients with fibromyalgia syndrome (FMS) and healthy controls.

Patients and methods

The study included 40 female patients (mean age 39.9±10.2 years; range, 22 to 52 years) diagnosed with primary FMS according to the American College of Rheumatology criteria (1990) and 40 healthy female volunteers (mean age 40.9±8.3 years; range, 25 to 53 years). The sociodemographic data of both groups were recorded. The disease duration and the number of tender points were recorded for patients with FMS, and venous blood samples were collected from the two groups for the measurement of serum VEGF and VEGFR-1 levels.

Results

The FMS and control groups were comparable in terms of age and body mass index (p>0.05). A comparison of the serum VEGF levels of the FMS and control groups revealed a statistically insignificant difference (p>0.05), while a comparison of the serum VEGF-1 levels of the FMS and control groups revealed a statistically significant difference (p<0.05).

Conclusion

Serum VEGFR-1 levels were higher in patients with FMS, while the serum VEGF levels of the FMS patients did not differ from those of the healthy controls.

Effects of attachment-based compassion therapy (ABCT) on brain-derived neurotrophic factor and low-grade inflammation among fibromyalgia patients: A randomized controlled trial

Fibromyalgia (FM) is a disabling syndrome characterized by chronic pain associated with fatigue. Its pathogenesis is unknown, but alterations in central sensitization, involving an imbalance of brain-derived neurotrophic factor (BDNF) and inflammatory biomarkers, appear to be implicated. The aim of this study was to evaluate the impact of attachment-based compassion therapy (ABCT) on levels of BDNF, the inflammatory markers TNF-α, IL-6, IL-10, and the C-reactive protein (CRP), analysing whether biomarkers play a mediating/moderating role in improvements in FM functional status. Thirty-four female patients with FM participated in a RCT and were assigned to ABCT or relaxation therapy. Blood extractions were conducted at baseline and post-intervention, with self-report assessments of functional status (FIQ) at baseline, post-intervention and 3-month follow-up. A pro-inflammatory composite was obtained by summing up IL-6, TNF-α and CRP normalized values. Non-parametric tests, analysis of variance and regression models were used to evaluate treatment and mediation/moderation. Compared to relaxation therapy, ABCT showed significant improvements in FIQ and decreases in BDNF, CRP, and pro-inflammatory composite. Changes in BDNF had a mediating role in FIQ. ABCT seems to reduce BDNF and appears to have anti-inflammatory effects in FM patients. Reductions in BDNF could be a mechanism of FM functional status improvement.

Clinical Trial Registration:http://ClinicalTrials.gov, identifier NCT02454244. Date: May 27th, 2015.

A narrative review on the difficulties associated with fibromyalgia diagnosis

Fibromyalgia presents a clinical enigma as its pathophysiology is not well understood and its symptoms are nonspecific and overlap with many disorders, making its diagnosis a challenge for clinicians and researchers. Efforts have been made to develop a set of diagnostic criteria for this disorder. However, these criteria rely heavily on expert clinician opinion and produce a large heterogeneity within the diagnosed population. With no present specific technique reflecting the underlying pathophysiology of fibromyalgia, a definitive diagnosis of fibromyalgia remains elusive. This review discusses some problems and challenges associated with fibromyalgia diagnosis and presents some novel findings on the pathophysiological nature of fibromyalgia.

Development and validation of an immunosensor for monocyte chemotactic protein 1 using a silicon photonic microring resonator biosensing platform

OBJECTIVES

We report the development of an optical immunosensor for the detection of monocyte chemotactic protein 1 (MCP-1) in serum samples. MCP-1 is a cytokine that is an emerging biomarker for several diseases/disorders, including ischemic cardiomyopathy, fibromyalgia, and some cancers.

DESIGN AND METHODS

The detection of MCP-1 was achieved by performing a sandwich immunoassay on a silicon photonic microring resonator sensor platform. The resonance wavelengths supported by microring sensors are responsive to local changes in the environment accompanying biomarker binding. This technology offers a modularly multiplexable approach to detecting analyte localization in an antibody-antigen complex at the sensor surface.

RESULTS

The immunosensor allowed the rapid detection of MCP-1 in buffer and spiked human serum samples. An almost 2 order of magnitude linear range was observed, between 84.3 and 1582.1pg/mL and the limits of blank and detection were determined to be 0.3 and 0.5pg/mL, respectively. The platform's ability to analyze MCP-1 concentrations across a clinically-relevant concentration range was demonstrated.

CONCLUSIONS

A silicon photonic immunosensor technology was applied to the detection of clinically-relevant concentrations of MCP-1. The performance of the sensor was validated through a broad dynamic range and across a number of suggested clinical cut-off values. Importantly, the intrinsic scalability and rapidity of the technology makes it readily amenable to the simultaneous detection of multiplexed biomarker panels, which is particularly needed for the clinical realization of inflammatory diagnostics.

The design of a new truncated and engineered alpha1-antitrypsin based on theoretical studies: an antiprotease therapeutics for pulmonary diseases

Alpha 1- antitrypsin (α1AT) a 54 kDa glycoprotein is a protease inhibitor. In the absence of α1AT, elastase released by lung macrophages, was not inhibited and lead to elastin breakdown and pulmonary problems such as emphysema or COPD. α1AT has three site of N-glycosylation and a characteristic reactive central loop (RCL). As small-scale medicines are preferred for pulmonary drug delivery, in this study α1ATs (1, 2, 3, 4 and 5) were engineered and shortened from the N-terminal region. In order to investigate the effect of different mutations and the deletion of 46 amino acids theoretical studies were performed. Homology modeling was performed to generate the 3D structure of α1ATs. The 10 ns Molecular Dynamic (MD) simulations were carried out to refine the models. Results from MD and protein docking showed that α1AT2 has the highest binding affinity for neutrophil elastase, provided the basis for the experimental phase in which sequences from the five α1AT constructs were inserted into the expression vector pGAPZα and expressed in the yeast Pichia pastoris. Although, the α1AT2 construct has the highest inhibitory activity even more that the native construct (α1AT5), results indicated the presence of protease inhibitory function of all the proteins' construct against elastase.

α1-Antitrypsin in fibromyalgia: results of a randomized, placebo-controlled, double-blind and crossover pilot trial

OBJECTIVE

To assess clinical effect of a human plasma-derived alpha-1 antitrypsin (AAT) concentrate in reducing pain severity of patients with fibromyalgia (FM).

METHODS

Thirteen subjects with FM completed a randomized, double-blind, placebo-controlled, crossover study which consisted of 9 weeks trial of AAT or placebo with a washout period of 6 weeks. Primary efficacy endpoint was change on pain severity score, assessed by a daily visual analogue scale (VAS) for pain. Other outcome measures included a tender point score, the Fibromyalgia Impact Questionnaire, (FIQ), the Medical Outcomes Study Short Form 36 (SF-36), the Health Assessment Questionnaire Disability Index (HAQ-DI), the Hospital Anxiety and Depression Scale (HADS) and tiredness score evaluated by VAS.

RESULTS

No statistically significant differences were observed in either pain severity or other secondary outcome measures in either of the treatment groups, or between treatment groups in either of the treatment periods. No carryover or order of intervention effect was observed from one treatment to the other. Both investigational interventions were generally well tolerated, and vital signs during the drug infusions were within the respective normal ranges.

CONCLUSION

Treatment with a human plasma-derived AAT concentrate did not demonstrate significant improvement over placebo on reducing pain severity and other symptoms of FM. Further research should examine other FM subpopulations and drug doses.

Alpha-1 antitrypsin: a potent anti-inflammatory and potential novel therapeutic agent

Alpha-1 antitrypsin (AAT) has long been thought of as an important anti-protease in the lung where it is known to decrease the destructive effects of major proteases such as neutrophil elastase. In recent years, the perception of this protein in this simple one dimensional capacity as an anti-protease has evolved and it is now recognised that AAT has significant anti-inflammatory properties affecting a wide range of inflammatory cells, leading to its potential therapeutic use in a number of important diseases. This present review aims to discuss the described anti-inflammatory actions of AAT in modulating key immune cell functions, delineate known signalling pathways and specifically to identify the models of disease in which AAT has been shown to be effective as a therapy.

Inflammatory/stress feedback dysregulation in women with fibromyalgia

OBJECTIVE

Although one of the current hypotheses of the aetiology of fibromyalgia (FM) syndrome involves inflammatory and neuroendocrine disorders, its biophysiology still remains unclear. The purpose of the present investigation was to study the systemic inflammatory and stress responses, as well as the innate response mediated by monocytes and neutrophils in FM patients.

METHODS

Twenty-five women diagnosed with primary FM and 20 age-matched healthy women (control group) were enrolled in the study. Circulating 'neuroendocrine-stress' biomarkers (CRH, ACTH, cortisol, NA, eHsp72, serotonin and IGF-1) were evaluated by ELISA. Serum IL-8 and CRP concentrations were also determined by ELISA, and inflammatory cytokine release by monocytes [IL-1β, TNFα, IL-6, IL-10, IL-18, monocyte chemotactic protein-1 (MCP-1) and RANTES] was evaluated by the Luminex BioPlex system. The phagocytic process of neutrophils (chemotaxis, phagocytosis and microbicide capacity) was also evaluated.

RESULTS

FM patients showed an inflammatory state accompanied by an altered stress response. This is mainly manifested by high circulating levels of IL-8 and CRP (in 100% of the FM group), high circulating levels of cortisol, and increased systemic levels of NA and eHsp72. There is also increased release of inflammatory cytokines (IL-1β, TNFα, IL-6, IL-10, IL-18 and MCP-1) by monocytes, and enhanced activation of the functional capacity of neutrophils (chemotactic, phagocytic and fungicidal activities).

CONCLUSION

An inflammatory/stress feedback dysregulation underlies FM. Whether dysregulation of the stress response is the cause of the inflammatory dysregulation or vice versa is also discussed.

Systematic review with meta-analysis: cytokines in fibromyalgia syndrome

BACKGROUND

To perform a systematic review and meta-analysis on cytokine levels in patients with fibromyalgia syndrome (FMS).

METHODS

Through December 2010 we systematically reviewed the databases PubMed, MEDLINE, and PsycINFO and screened the reference lists of 22 review articles for suitable original articles. Original articles investigating cytokines in patients with FMS were included. Data were extracted by two independent authors. Differences of the cytokine levels of FMS patients and controls were summarized by standardized mean differences (SMD) using a random effects model. Study quality was assessed applying methodological scores: modified Center of Evidence Based Medicine, Newcastle-Ottawa-Scale, and Würzburg Methodological Quality Score.

RESULTS

Twenty-five articles were included investigating 1255 FMS patients and 800 healthy controls. Data of 13/25 studies entered meta-analysis. The overall methodological quality of studies was low. The results of the majority of studies were not comparable because methods, investigated material, and investigated target cytokines differed. Systematic review of the selected 25 articles revealed that FMS patients had higher serum levels of interleukin (IL)-1 receptor antagonist, IL-6, and IL-8, and higher plasma levels of IL-8. Meta-analysis of eligible studies showed that FMS patients had higher plasma IL-6 levels compared to controls (SMD = -0.34 [-0.64, -0.03] 95% CI; p = 0.03). The majority of investigated cytokines were not different between patients and controls.

CONCLUSIONS

The pathophysiological role of cytokines in FMS is still unclear. Studies of higher quality and with higher numbers of subjects are needed.

Efficacy of alpha1-antitrypsin augmentation therapy in conditions other than pulmonary emphysema

Up to now alpha 1-antitrypsin (AAT) augmentation therapy has been approved only for commercial use in selected adults with severe AAT deficiency-related pulmonary emphysema (i.e. PI*ZZ genotypes as well as combinations of Z, rare and null alleles expressing AAT serum concentrations <11 μmol/L). However, the compassionate use of augmentation therapy in recent years has proven outstanding efficacy in small cohorts of patients suffering from uncommon AAT deficiency-related diseases other than pulmonary emphysema, such as fibromyalgia, systemic vasculitis, relapsing panniculitis and bronchial asthma. Moreover, a series of preclinical studies provide evidence of the efficacy of AAT augmentation therapy in several infectious diseases, diabetes mellitus and organ transplant rejection. These facts have generated an expanding number of medical applications and patents with claims for other indications of AAT besides pulmonary emphysema. The aim of the present study is to compile and analyze both clinical and histological features of the aforementioned published case studies and reports where AAT augmentation therapy was used for conditions other than pulmonary emphysema. Particularly, our research refers to ten case reports and two clinical trials on AAT augmentation therapy in patients with both AAT deficiency and, at least, one of the following diseases: fibromyalgia, vasculitis, panniculitis and bronchial asthma. In all the cases, AAT was successfully applied whereas previous maximal conventional therapies had failed. In conclusion, laboratory studies in animals and humans as well as larger clinical trials should be, thus, performed in order to determine both the strong clinical efficacy and security of AAT in the treatment of conditions other than pulmonary emphysema.

Abnormal overexpression of mastocytes in skin biopsies of fibromyalgia patients

Formalin-fixed, paraffin-embedded skin tissue sections were collected from a matched cohort of 63 fibromyalgia syndrome (FMS) patients and 49 volunteers from the general population with both alpha1-antitrypsin (AAT) normal and deficiency variants. These tissues were examined for the expression of the broad-spectrum inhibitor AAT, the serine proteinases elastase and tryptase, the proinflammatory cytokines MCP-1 and TNFα, the endothelium biomarker VEGF, and the inflammation/nociception-related receptor PAR(2). The most relevant finding of the study was a significantly increased number of mast cells (MCs) in the papillary dermis of all FMS patients (greater than or equal to five to 14 per microscopic high power field) compared to zero to one in controls (p < 0.001). MCs strongly stained with tryptase, AAT and PAR(2) antibodies, exhibited a spindle-like shape and were uniformly distributed around blood vessels and appendages. MCP-1 and VEGF expressed weak/moderate positivity in most samples, with a higher expression in controls than in FMS patients (p < 0.001 and 0.051, respectively). No differences in elastase and TNFα were found between both groups. Moreover, no histological differences were found between samples from AAT deficiency and normal AAT phenotypes. Our results indicate that FMS is a MC-associated condition. MCs are present in skin and mucosal surfaces throughout the human body, and are easily stimulated by a number of physical, psychological, and chemical triggers to degranulate, releasing several proinflammatory products which are able to generate nervous peripheral stimuli causing CNS hypersensitivity, local, and systemic symptoms. Our findings open new avenues of research on FMS mechanisms and will benefit the diagnosis of patients and the development of therapeutics.