Sympathetic nervous system plays an important role in the relationship between immune mediated diseases

Heart Rate Variability in Patients of Ankylosing Spondylitis: A Systematic Review and Meta-Analysis

Patients with ankylosing spondylitis (AS) have a significantly higher risk of cardiovascular morbidities. The participation of the autonomic nervous system (ANS) in AS is still unknown and inconclusive. Heart rate variability (HRV) is defined as the variability of the time interval between two consecutive heartbeats. This meta-analysis aims to detect the association of HRV and its various parameters with AS patients by comparing them to healthy controls. Research literature was searched in PubMed, Embase, and Cochrane Library databases from inception to April 2022. The Review Manager 5 (RevMan) Version 5.4 software was used to analyze the data. In addition, the protocol of systematic review is registered in the PROSPERO database with ID CRD42022336484. This study includes a total of nine case-control studies with a total of 923 patients; 409 with AS and 514 healthy controls. The root mean square of successive differences between normal heartbeats (RMSSD) [standardized mean difference (SMD); -0.47, 95% CI: -0.69 to -0.25, p < 0.0001], proportion of NN50 (pNN50) (SMD; -0.89, 95% CI: -1.74 to -0.04, p = 0.04) and HRV (SMD; -1.11, 95% CI: -1.53 to 0.69, P < 0.00001) were significantly low in AS cases compared to healthy controls. The HRV value was also significantly low in patients with high Bath ankylosing spondylitis disease activity (BASDAI) index (SMD: -1.45, 95% CI: -2.45 to -0.36, p < 0.009). HRV (parasympathetic activity) was significantly lowered in AS patients compared to healthy controls.

Autoimmunity in Long Covid and POTS

Orthostatic intolerance and other autonomic dysfunction syndromes are emerging as distinct symptom clusters in Long Covid. Often accompanying these are common, multi-system constitutional features such as fatigue, malaise and skin rashes which can signify generalized immune dysregulation. At the same time, multiple autoantibodies are identified in both Covid-related autonomic disorders and non-Covid autonomic disorders, implying a possible underlying autoimmune pathology. The lack of specificity of these findings precludes direct interpretations of cause and association, but their prevalence with its supporting evidence is compelling.

Cardiac Autonomic Modulation Is Different in Terms of Clinical Variant of Multiple Sclerosis

This study evaluates whether the cardiac autonomic response to head-up tilt test (HUTT) differs between patients with relapsing-remitting multiple sclerosis (RRMS) and those with progressive MS (PMS) as compared to healthy controls (HC). Baroreflex sensitivity, cardiac parameters, heart rate (HRV) and blood pressure variability (BPV) were compared between 28 RRMS, 21PMS and 25 HC during HUTT. At rest, PMS patients had higher values of the sympathovagal ratio, a low-frequency band HRV (LFnu-RRI) and lower values of parasympathetic parameters (HFnu-RRI, HF-RRI) compared to RRMS and HC. Resting values of cardiac parameters were significantly lower in RRMS compared to PMS patients. No intergroup differences were observed for post-tilt cardiac and autonomic parameters, except for delta HF-RRI with lower values in the PMS group. The MS variant corrected for age, sex and Expanded Disability Status Scale (EDSS) score was an independent predictor of changes in the sympathovagal ratio as measured by HRV. Furthermore, a higher overall EDDS score was related to a higher sympathovagal ratio, lower parasympathetic parameters at rest, and decrease post-tilt changes of the sympathovagal ratio of sBP BPV. Autonomic imbalance is markedly altered in the MS patient group compared to control changes were most pronounced in the progressive variant of MS disease. The MS variant appeared to have a potential influence on cardiac autonomic imbalance at rest.

Heart rate variability is differentially altered in multiple sclerosis: implications for acute, worsening and progressive disability

Background

Sympathovagal imbalance has been associated with poor prognosis in chronic diseases, but there is conflicting evidence in multiple sclerosis.

Objectives

The objective of this study was to investigate the autonomic nervous system dysfunction correlation with inflammation and progression in multiple sclerosis.

Methods

Heart rate variability was analysed in 120 multiple sclerosis patients and 60 healthy controls during supine rest and head-up tilt test; the normalised units of low frequency and high frequency power were considered to assess sympathetic and vagal components, respectively. Correlation analyses with clinical and radiological markers of disease activity and progression were performed.

Results

Sympathetic dysfunction was closely related to the progression of disability in multiple sclerosis: progressive patients showed altered heart rate variability with respect to healthy controls and relapsing–remitting patients, with higher rest low frequency power and lacking the expected low frequency power increase during the head-up tilt test. In relapsing–remitting patients, disease activity, even subclinical, was associated with lower rest low frequency power, whereas stable relapsing–remitting patients did not differ from healthy controls. Less sympathetic reactivity and higher low frequency power at rest were associated with incomplete recovery from relapse.

Conclusions

Autonomic balance appears to be intimately linked with both the inflammatory activity of multiple sclerosis, which is featured by an overall hypoactivity of the sympathetic nervous system, and its compensatory plastic processes, which appear inefficient in case of worsening and progressive multiple sclerosis.

Genome-wide association study for cytokines and immunoglobulin G in swine

Increased disease resistance through improved immune capacity would be beneficial for the welfare and productivity of farm animals. To identify genomic regions responsible for immune capacity traits in swine, a genome-wide association study was conducted. In total, 675 pigs were included. At 21 days of age, all piglets were vaccinated with modified live classical swine fever vaccine. Blood samples were sampled when the piglets were 20 and 35 days of age, respectively. Four traits, including Interferon-gamma (IFN-γ) and Interleukin 10 (IL-10) levels, the ratio of IFN-γ to IL-10 and Immunoglobulin G (IgG) blocking percentage to CSFV in serum were measured. All the samples were genotyped for 62,163 single nucleotide polymorphisms (SNP) using the Illumina porcineSNP60k BeadChip. After quality control, 46,079 SNPs were selected for association tests based on a single-locus regression model. To tackle the issue of multiple testing, 10,000 permutations were performed to determine the chromosome-wise and genome-wise significance level. In total, 32 SNPs with chromosome-wise significance level (including 4 SNPs with genome-wise significance level) were identified. These SNPs account for 3.23% to 13.81% of the total phenotypic variance individually. For the four traits, the numbers of significant SNPs range from 5 to 15, which jointly account for 37.52%, 82.94%, 26.74% and 24.16% of the total phenotypic variance of IFN-γ, IL-10, IFN-γ/IL-10, and IgG, respectively. Several significant SNPs are located within the QTL regions reported in previous studies. Furthermore, several significant SNPs fall into the regions which harbour a number of known immunity-related genes. Results herein lay a preliminary foundation for further identifying the causal mutations affecting swine immune capacity in follow-up studies.

Pupillometric assessment of autonomic nervous system in children with allergic rhinitis

OBJECTIVE

The purpose of this study was to investigate autonomic nervous system dysfunction by measuring pupil sizes in pediatric patients with allergic rhinitis.

SUBJECTS AND METHODS

The study group consisted of 60 children (28 girls and 32 boys) who were age and gender matched with the control group, which also consisted of 60 children (26 girls and 34 boys). The diagnosis of allergic rhinitis was based on the history, physical examination and skin prick test performed by an allergologist. Pupil diameter measurements were performed using the pupillometer incorporated in the NİDEK OPD-Scan.

RESULTS

In the allergic rhinitis group, mean photopic and mesopic pupil diameters were 3.52 ± 0.07 and 5.98 ± 0.21, respectively, while in the control group, corresponding measurements were 4.03 ± 0.18 and 6.55 ± 0.16. There was a significant difference for photopic and mesopic pupil diameter between the groups (p < 0.001).

CONCLUSION

This study showed that the pupil size in response to a light stimulus in children with allergic rhinitis was smaller than that of the control group and may indicate parasympathetic hyperactivity and sympathetic hypoactivity.

The investigation of autonomic functions in patients with psoriasis

BACKGROUND

Psoriasis is a common Th1-mediated skin disease whose etiology remains obscure. Loss of sweating caused by retention hyperkeratosis is seen in psoriasis plaques, which is likely to have resulted from autonomic dysfunction.

OBJECTIVE

In the present study, we aimed to evaluate autonomic nervous system (ANS) functions with regard to psoriasis and to examine whether there is an underlying ANS dysfunction.

MATERIALS AND METHODS

Fifty adult patients with plaque-type psoriasis and 20 healthy controls were enrolled in the present study. RESULTS  In this study, R-R interval variation (RRIV) was used to evaluate the parasympathetic system. No statistically significant difference was detected when RRIV values of the patient and the control groups were evaluated during normal and deep breathing (P > 0.05). It was determined that parasympathetic activity in the patient group remained unaffected. The sympathetic skin response (SSR) method was used for the evaluation of the sympathetic system. It was found that SSR latency and amplitude values of upper and lower extremities of the patient group were prolonged in comparison to those of the control group. The change in SSR latency of the upper extremity was found to be statistically significant (P < 0.05), whereas the changes in hand amplitude, foot latency, and foot amplitude values were not statistically significant (P > 0.05). It was determined that sympathetic activity in the patient group was affected.

CONCLUSION

In conclusion, we detected that a dysfunction was present in sympathetic nervous systems of patients with psoriasis. The parasympathetic nervous system functions were normal in patients with psoriasis.

Immune cells listen to what stress is saying: neuroendocrine receptors orchestrate immune function

Over the past three decades, the field of psychoneuroimmunology research has blossomed into a major field of study, gaining interests of researchers across all traditionally accepted disciplines of scientific research. This chapter provides an overview of our current understanding in defining neuroimmune interactions with a primary focus of discussing the neuroendocrine receptor activity by immune cells. This chapter highlights the necessity of neuroimmune responses as it relates to a better understanding of the pathophysiological mechanisms of health and disease.

The subclinic autonomic dysfunction in patients with Behçet disease: an electrophysiological study

Studies that have evaluated autonomic nervous system (ANS) function in Behçet disease (BD) are rare and have indicated conflicting results with different degrees of involvement. The aim of this study was to investigate ANS function by using electrophysiological tests in patients with BD and to determine the relationship between the disease activity parameters and the indicators of autonomic activity. We included 70 BD patients and 50 healthy controls. Demographic characteristics including age, sex, and disease duration were recorded. A detailed neurological examination was performed, and clinical autonomic symptoms were recorded. The Behçet Disease Current Activity Form (BDCAF) was used to determine the disease activity. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels were determined for laboratory activity. The electrophysiological assessments of ANS function were performed by sympathetic skin response (SSR) and R-R interval variation (RRIV) tests. The mean values of sympathetic (SSR latency and amplitude) and parasympathetic (RRIV at rest [R%] and deep breathing [D%], D% - R%, and D%/R%) parameters were compared, and any correlations between ANS parameters and clinical disease characteristics were determined. Seventy BD patients (23 males, 47 females) with a mean age of 41.2 ± 10.01 years and 50 control subjects (18 males, 32 females) with a mean age of 39.5 ± 8.94 years were included in the study. All the subjects were totally symptom free with respect to ANS involvement, and the subjects in both groups had normal neurological examination findings. The demographic characteristics were similar between the groups. The mean latency of SSR was increased (1.4 ± 0.4 vs 0.7 ± 0.8), and R% (0.3 ± 0.3 vs 0.5 ± 0.4) and D% (0.3 ± 0.3 vs 0.6 ± 0.5) values were decreased in BD patients compared to control subjects. No correlation was found between BDCAF scores and ANS variables. However, there was a significant correlation between SSR latency and ESR and CRP values (p < 0.01, r = -0.25, r = -0.31, respectively) in the patient group, indicating a more sympathetic dysautonomia in patients with active laboratory parameters. In conclusion, our study indicates a subclinical sympathetic and parasympathetic autonomic dysfunction in patients with BD, which may be related with disease activity. As the early recognition of abnormalities in ANS may be very important in order to prevent excessive morbidity, simple electrophysiological methods are suggested to identify Behçet patients at high risk for symptomatic dysautonomia.

Mapping quantitative trait loci for cytokines in the pig

Increased disease resistance through improved general immune capacity would be beneficial for the welfare and productivity of farm animals. Cytokines are essential diagnostic parameters in veterinary practice. To identify quantitative trait loci (QTL) for cytokine levels in serum in the pig, Interferon-gamma (IFN-γ) and Interleukin 10 (IL-10) levels and the ratio of IFN-γ to IL-10 were measured in a composite pig population, before and after challenge with modified live CSF (classical swine fever) vaccine. Through interval mapping using the variance component approach and the permutation test, 11 QTL (five for IFN-γ, two for IL-10 and four for the ratio of IFN-γ to IL-10) with significance levels of P < 0.10 were identified, of which five were significant at the P < 0.05 level. The most significant QTL (P < 0.01) was found on chromosome 16, with effect on the ratio of IFN-γ to IL-10. Within these QTL regions, a number of known genes were revealed and their potential relationships to the studied traits were discussed. Some of these genes may serve as candidate genes for these traits in swine.

Cardiac autonomic imbalance in children with allergic rhinitis

The involvement of autonomic imbalance has been reported in the pathogenesis of hypersensitivity reactions. Allergic diseases are more frequent in children and some of predisposing factors may be changed according to the increasing age, but the involvement of autonomic imbalance has not been investigated in pediatric population. In this cross-sectional, case-control study, we evaluated the autonomic system by measuring heart rate variability (HRV) in pediatric patients with allergic rhinitis. Thirty-five pediatric patients with allergic rhinitis and 36 healthy children (mean age 11 +/- 2.7, and 12 +/- 3 years, respectively) were enrolled in the study. Age and gender were not different between the groups. The diagnosis of allergic rhinitis was based on the history, symptoms, and skin prick tests. Participants with acute infection, nasal polyposis, bronchial asthma, and any other medical problems, assessed by history, physical examination and routine laboratory tests, were excluded. Twenty-four hour ambulatory electrocardiographic recordings were obtained, and the time domain and frequency domain indices of HRV were analyzed. We found significant increase in calculated HRV variables in children with allergic rhinitis compared to controls, which reflect parasympathetic tones, such as number of R-R intervals exceeding 50 ms, root mean square of successive differences between normal sinus R-R intervals, the percentage of difference between adjacent normal R-R intervals, and high frequency. These results indicate that HRV is increased, which implies sympathetic withdrawal and parasympathetic predominance. We propose that autonomic imbalance may be involved in the pathophysiology of allergic rhinitis in pediatric patients.

Matrix metalloproteinase-2 promoter variability in psoriasis

The expression of matrix metalloproteinase-2 was observed to be significantly upregulated in psoriasis. The aim of this study was to associate the DNA polymorphic variants in MMP-2 promoter gene with psoriasis and/or with psoriasis phenotypes related to psoriasis and comorbid heredity. In the total of 582 Czech Caucasian individuals (386 patients with psoriasis and 196 controls of similar age and sex distribution without personal or family history of chronic disease of the skin), four MMP-2 promoter polymorphisms (-1575G/A, -1306C/T, -790T/G and -735C/T) were detected by PCR methods. A significant association of GG genotype of -790 MMP-2 polymorphism with psoriasis was observed (Pcorr = 0.04). Although no significant case-control differences in frequency of associated GG(-1575)CC(-1306)TT(-790) MMP-2 promoter genotype were observed, the genotype was found to be significantly less frequent in patients with family history of psoriasis (close as well as distant), family history of diabetes and personal history of allergy (2/11 vs. 55/32, odds ratio (OR) for GGCCTT 0.11, 95% confidential interval 0.02-0.50, Pcorr = 0.01). The significant difference between psoriatic patients with positive anamnestic data on diabetes, psoriasis and allergy compared with psoriatic patients that have only positive family history of diabetes was also observed (2/11 vs. 38/31, P = 0.009, Pcorr = 0.04; OR 0.15, 95% CI = 0.03-0.72 for psoriatic patients with GGCCTT genotype and family history of psoriasis, diabetes and personal history of allergy). To conclude, the associated GGCCTT genotype in the promoter of MMP-2 gene was less frequent in patients with positive family history of psoriasis, diabetes and personal history of allergy compared with psoriatic patients without them (2/11 vs. 68/57, P = 0.007, Pcorr = 0.04; OR = 0.15, 95% CI = 0.03-0.72 for psoriatic patients with family history of psoriasis and diabetes and with allergy). Based on our results, we suggest that the MMP-2 located in the psoriasis susceptibility region on 16q (psoriasis susceptibility 8, PSORS8) should be considered as a gene modulator of psoriasis in specific subgroups of patients. In the future, similar genetic characteristics could contribute to the data assembly of genetic predisposition to psoriasis and could lead to therapy improvement based on time-proved individual pharmacogenetic aspects detected in psoriasis patients.

Protective effects of Helicobacter pylori against gastroesophageal reflux disease may be due to a neuroimmunological anti-inflammatory mechanism

There is some evidence that Helicobacter pylori infection has a protective effect against gastroesophageal reflux disease (GORD) and its complications such as Barrett's oesophagus and oesophageal adenocarcinoma. In this paper, we propose that a neuroimmunological mechanism is responsible for the protective effect of H. pylori on GORD. H. pylori infection of the gastric mucosa induces a T helper1-like immune response and production of pro-inflammatory cytokines. These cytokines can inhibit local sympathetic tone, whereas they increase systemic sympathetic tone. Increased sympathetic tone can induce an anti-inflammatory milieu, which in turn can inhibit inflammation in the oesophagus and lower oesophageal sphincter (LOS). Furthermore, H. pylori infection may stimulate the cholinergic anti-inflammatory pathway. It has been suggested that reflux-induced oesophageal inflammation plays an important role in the pathogenesis of reflux oesophagitis. Reduction of oesophageal inflammation by increased systemic sympathetic tone and vagal activity may lead to a decrease in reflux-induced oesophageal injury and LOS dysfunction in GORD.

Short-term effects of pulsed electromagnetic fields after physical exercise are dependent on autonomic tone before exposure

The therapeutic application of pulsed electromagnetic fields (PEMFs) can accelerate healing after bone fractures and also alleviate pain according to several studies. However, no objective criteria have been available to ensure appropriate magnetic field strength or type of electromagnetic field. Moreover, few studies so far have investigated the physical principles responsible for the impact of electromagnetic fields on the human body. Existing studies have shown that PEMFs influence cell activity, the autonomic nervous system and the blood flow. The aim of this study is to examine the instantaneous and short-term effects of a PEMF therapy and to measure the impact of different electromagnetic field strengths on a range of physiological parameters, especially the autonomic nervous systems, determined by heart rate variability (HRV) as well as their influence on subjects' general feeling of well-being. The study comprised experimental, double-blind laboratory tests during which 32 healthy male adults (age: 38.4+/-6.5 years) underwent four physical stress tests at standardised times followed by exposure to pulsed magnetic fields of varying intensity [HPM, High Performance magnetic field; Leotec; pulsed signal; mean intensity increase: zero (placebo), 0.005, 0.03 and 0.09 T/s]. Exposure to electromagnetic fields after standardised physical effort significantly affected the very low frequency power spectral components of HRV (VLF; an indicator for sympathetically controlled blood flow rhythms). Compared to placebo treatment, exposure to 0.005 T/s resulted in accelerated recovery after physical strain. Subjects with lower baseline VLF power recovered more quickly than subjects with higher VLF when exposed to higher magnetic field strengths. The application of electromagnetic fields had no effect on subjects' general feeling of well-being. Once the magnetic field exposure was stopped, the described effects quickly subsided. PEMF exposure has a short-term dosage-dependent impact on healthy subjects. Exposure to PEMF for 20 min resulted in more rapid recovery of heart rate variability, especially in the very low frequency range after physical strain. The study also showed the moderating influence of the subjects' constitutional VLF power on their response to PEMF treatment. These findings have since been replicated in a clinical study and should be taken into consideration when PEMF treatment is chosen.

Paeoniflorin induced immune tolerance of mesenteric lymph node lymphocytes via enhancing beta 2-adrenergic receptor desensitization in rats with adjuvant arthritis

Paeoniflorin (Pae), a monoterpene glucoside, is one of the main bioactive components of total glucosides of paeony (TGP) extracted from the root of Paeonia lactiflora. TGP has anti-inflammatory and immunoregulatory effects. In this study, we investigated the effects of Pae on inflammatory and immune responses to the mesenteric lymph node (MLN) lymphocytes and the mechanisms by which Pae regulates beta 2-adrenergic receptor (beta 2-AR) signal transduction in adjuvant arthritis (AA) rats. The onset of secondary arthritis in rats appeared around day 14 after injection of Freund's complete adjuvant (FCA). Remarkable secondary inflammatory response and lymphocytes proliferation were observed in AA rats, along with the decrease of anti-inflammatory cytokines interleukin (IL)-4 and transforming growth factor-beta 1 (TGF-beta 1) of MLN lymphocytes, and the increase of pro-inflammatory cytokine IL-2. The administration of Pae (50, 100 mg kg(-1), days 17-24) significantly diminished the secondary hind paw swelling and arthritis scores, reversed the changes of cytokines as discussed above, and further decreased the lowered proliferation of MLN lymphocytes in AA rats. In vitro, Pae restored the previously increased level of cAMP of MLN lymphocytes at the concentrations of 12.5, 62.5 and 312.5 mg l(-1). Meanwhile, Pae increased protein expressions of beta 2-AR and GRK2, and decreased that of beta-arrestin 1, 2 of MLN lymphocytes in AA rats. These results suggested that Pae might induce the Th1 cells immune tolerance, which then shift to Th2, Th3 cells mediated activities to take effect the anti-inflammatory and immunoregulatory effects. The mechanisms of Pae on beta 2-AR desensitization and beta 2-AR-AC-cAMP transmembrane signal transduction of MLN lymphocytes play crucial roles in pathogenesis of this disease.