Social media platforms, comment boards, and online market places have created unprecedented potential for social influence and resulting opinion dynamics such as polarization. We propose an encompassing model that captures competing micro-level theories of social influence. Conducting an online lab-in-the-field experiment, we observe that individual opinions shift linearly towards the mean of others' opinions. From this finding, we predict the macro-level opinion dynamics resulting from social influence. We test our predictions using data from another lab-in-the-field experiment and find that opinion polarization decreases in the presence of social influence. We corroborate these findings with large-scale field data.
Background: Inflammation and autoimmune responses contribute to the pathophysiology of Long COVID, and its affective and chronic fatigue syndrome (CFS) symptoms, labeled "the physio-affective phenome." Objectives: To investigate whether Long COVID and its physio-affective phenome are linked to autoimmunity to the tight junction proteins, zonulin and occludin (ZOOC), and immune reactivity to lipopolysaccharides (LPS), and whether the latter are associated with signs of human herpes virus-6 reactivation (HHV-6), autoimmunity directed against oligodendrocyte and neuronal proteins, including myelin basic protein (MBP). Methods: IgA /IgM/IgG responses to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), HHV-6, ZOOC, and neuronal proteins, C-reactive protein (CRP) and advanced oxidation protein products (AOPP), were measured in 90 Long COVID patients and 90 healthy controls. The physio-affective phenome was conceptualized as a factor extracted from physical and affective symptom domains. Results: Neural network identified IgA directed to LPS (IgA-LPS), IgG-ZOOC, IgG-LPS, and IgA-ZOOC as the most important variables associated with Long COVID diagnosis with an area under the ROC curve of 0.755. Partial Least Squares analysis showed that 40.9% of the variance in the physio-affective phenome was explained by CRP, IgA-MPB and IgG-MBP. A large part of the variances in both autoimmune responses to MBP (36.3-39.7%) was explained by autoimmunity (IgA and IgG) directed to ZOOC. The latter was strongly associated with indicants of HHV-6 reactivation, which in turn was associated with increased IgM-SARS-CoV-2. Conclusions: Autoimmunity against components of the tight junctions and increased bacterial translocation may be involved in the pathophysiology of Long COVID's physio-affective phenome.
Abstract Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder with a high co‐occurrence with affective dysregulation. Affective disorders have been associated with specific changes in the PUFA and cholesterol profile. In IBS, similar changes may be present as have been reported in patients with affective disorders. This exploratory study investigates (i) the level of affective dysregulation (AD) in IBS patients and healthy controls; (ii) PUFA and cholesterol profiles in IBS patients compared with controls; and (iii) associations between PUFA and cholesterol parameters with the level of AD. Blood samples were obtained for determination of the FA composition of plasma phospholipids and serum cholesterol in 23 diarrheapredominant IBS patients and 23 healthy matched controls. AD was scored using the Symptom Check List depression scale, the Hospital Anxiety and Depression Scale, and the Hamilton Depression Rating Scale. The level of AD was higher in IBS patients compared with controls. PUFA and cholesterol profiles did not differ significantly between groups. Total n−3 PUFA and cholesterol were significantly negatively associated and the ratio of n−6 to n−3 PUFA and the ratio of arachidonic acid to EPA were significantly positively associated with the level of AD. The findings of the present study reveal that AD was higher in IBS patients compared with healthy controls and that changes in PUFA and cholesterol profiles were significantly associated with the level of AD. These results warrant further studies regarding the role of PUFA and cholesterol status in the co‐occurrence of AD and functional gastrointestinal disorders.
Relapsing-remitting multiple sclerosis (RRMS) is defined by elevated IgG/IgA/IgM responses targeting Epstein-Barr Virus (EBV) nuclear antigen 1 (EBNA) and deoxyuridine-triphosphatases (dUTPases) of Human herpsesvirus-6 (HHV-6) and EBV. These responses suggest that the viruses are being replicated and reactivated. An increased prevalence of chronic fatigue syndrome, depression, and anxiety is associated with signs of immune activation in RRMS. Nevertheless, there is a lack of data regarding the association between viral reactivation and neuropsychiatric symptoms of RRMS. This study investigated the IgG/IgA/IgM responses to EBNA, and EBV and HHV-6-dUTPases, in 58 remitted RRMS patients and 63 normal controls. The McDonald criteria were employed to establish the diagnosis of MS. The Expanded Disability Status Scale (EDSS) and the Multiple Sclerosis Severity Score were employed to evaluate disabilities caused by RRMS. We evaluated the scores of the Hamilton Depression (HAMD) and Anxiety (HAMA) Rating Scales, and Fibro-Fatigue (FF) scale. One latent construct was extracted from the EDSS, MSSS, FF, HAMD, and HAMA scores. We discovered that the combined effects of IgG and IgM-HHV-6-dUTPAses accounted for 63.7% of the variance in this construct. Furthermore, the total FF, HAMA, and HAMD scores were substantially associated with the IgG and IgM-HHV-6-dUTPAses, accounting for approximately 38.7% to 51.0% of the variance. The three neuropsychiatric rating scale scores were also significantly correlated with IgA reactivity directed to both dUTPases and IgG/IgA/IgM to EBNA. The reactivation and replication of HHV-6 and EBV significantly contributes to chronic fatigue syndrome, as well as symptoms of depression and anxiety due to RRMS.
Abstract Background Major depressive disorder (MDD) is accompanied by activated neuro-immune pathways, increased physiosomatic and chronic fatigue-fibromyalgia (FF) symptoms. The most severe MDD phenotype, namely major dysmood disorder (MDMD), is associated with adverse childhood experiences (ACEs) and negative life events (NLEs) which induce cytokines/chemokines/growth factors. Aims To delineate the impact of ACE + NLEs on physiosomatic and FF symptoms in first episode (FE)-MDMD, and examine whether these effects are mediated by immune profiles. Methods ACEs, NLEs, physiosomatic and FF symptoms, and 48 cytokines/chemokines/growth factors were measured in 64 FE-MDMD patients and 32 normal controls. Results Physiosomatic, FF and gastro-intestinal symptoms belong to the same factor as depression, anxiety, melancholia, and insomnia. The first factor extracted from these seven domains is labeled the physio-affective phenome of depression. A part (59.0%) of the variance in physiosomatic symptoms is explained by the independent effects of interleukin (IL)-16 and IL-8 (positively), CCL3 and IL-1 receptor antagonist (inversely correlated). A part (46.5%) of the variance in physiosomatic (59.0%) symptoms is explained by the independent effects of interleukin (IL)-16, TNF-related apoptosis-inducing ligand (TRAIL) (positively) and combined activities of negative immunoregulatory cytokines (inversely associated). Partial Least Squares analysis shows that ACE + NLEs exert a substantial influence on the physio-affective phenome which are partly mediated by an immune network composed of interleukin-16, CCL27, TRAIL, macrophage-colony stimulating factor, and stem cell growth factor. Conclusions The physiosomatic and FF symptoms of FE-MDMD are partly caused by immune-associated neurotoxicity due to Th-1 polarization, T helper-1, and M1 macrophage activation and relative lowered compensatory immunoregulatory protection.
Circulating levels of somatomedins in man and rats are reduced by fasting and restored by refeeding. To determine the mechanisms for these alterations in somatomedin levels, the affinities and binding capacities of 125 I-labelled bovine GH (somatogenic binding sites) and of 125 I-labelled ovine prolactin (lactogenic binding sites) were assessed in liver homogenates from fasted and refed rats. Correlations were made with plasma immunoreactive somatomedin-C (Sm-C) and plasma insulin. During fasting and refeeding there was a close temporal relationship between the fall and the rise of plasma levels of Sm-C and insulin, and the number of hepatic GH binding sites. After fasting for 1 day, plasma Sm-C dropped by 68% and plasma insulin by 76% when compared with values before fasting. At the same time, GH binding capacity was significantly reduced (7·3 ± 2·8 ( s.e.m. ) pmol/liver v . controls, 20·3 ± 2·1 pmol/liver; P < 0·01). Refeeding for 24 h normalized plasma insulin levels and restored GH binding capacity to values before fasting (13·2 ± 2·4 v . 20·3 ± 2·1 pmol/liver; P > 0·05). Plasma Sm-C rose significantly with refeeding and returned to initial values at day 4 of refeeding (0·82 ± 0·10 v . 0·77 ± 0·07 units/ml; P > 0·05). In contrast, changes in prolactin binding sites correlated poorly with changes in plasma Sm-C. There was a modest decline with fasting significant only after 72 h (6·8 ± 0·6 v . 13·9 ± 3·2 pmol/liver; P < 0·05), and refeeding for 24 h did not restore prolactin binding (5·7 ± 1·2 pmol/liver). Since a number of reports suggest that fasting induces a state of tissue insensitivity to GH, our findings suggest that the reduction in hepatic GH binding capacity might be a mechanism for the fasting-induced reduction in Sm-C. The reduction in plasma insulin, which accompanies fasting, might play a permissive role in the intracellular metabolic events involved in Sm-C and GH receptor regulation.
There is now evidence that major depression is accompanied by decreased levels of omega3 poly-unsaturated fatty acids (PUFA), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). There is a strong comorbidity between major depression and chronic fatigue syndrome (CFS). The present study has been carried out in order to examine PUFA levels in CFS. In twenty-two CFS patients and 12 normal controls we measured serum PUFA levels using gas chromatography and mass spectrometry. We found that CFS was accompanied by increased levels of omega6 PUFAs, i.e. linoleic acid and arachidonic acid (AA), and mono-unsaturated fatty acids (MUFAs), i.e. oleic acid. The EPA/AA and total omega3/omega6 ratios were significantly lower in CFS patients than in normal controls. The omega3/omega6 ratio was significantly and negatively correlated to the severity of illness and some items of the FibroFatigue scale, i.e. aches and pain, fatigue and failing memory. The severity of illness was significantly and positively correlated to linoleic and arachidonic acid, oleic acid, omega9 fatty acids and one of the saturated fatty acids, i.e. palmitic acid. In CFS subjects, we found significant positive correlations between the omega3/omega6 ratio and lowered serum zinc levels and the lowered mitogen-stimulated CD69 expression on CD3+, CD3+ CD4+, and CD3+ CD8+ T cells, which indicate defects in early T cell activation. The results of this study show that a decreased availability of omega3 PUFAs plays a role in the pathophysiology of CFS and is related to the immune pathophysiology of CFS. The results suggest that patients with CFS should respond favourably to treatment with--amongst other things--omega3 PUFAs, such as EPA and DHA.
