Pathophysiological Role and Therapeutic Implications of Vitamin D in Autoimmunity: Focus on Chronic Autoimmune Diseases

Vitamin D is a pleiotropic secosteroid yielding multiple actions in human physiology. Besides the canonical regulatory activity on bone metabolism, several non-classical actions have been described and the ability of vitamin D to partake in the regulation of the immune system is particularly interesting, though far stronger and convincing evidence has been collected in in vitro as compared to in vivo studies. Whether vitamin D is able to regulate at physiological concentrations the human immune system remains unproven to date. Consequently, it is not established if vitamin D status is a factor involved in the pathogenesis of immune-mediated diseases and if cholecalciferol supplementation acts as an adjuvant for autoimmune diseases. The development of autoimmunity is a heterogeneous process, which may involve different organs and systems with a wide range of clinical implications. In the present paper, we reviewed the current evidences regarding vitamin D role in the pathogenesis and management of different autoimmune diseases

Excellent outcome in patients with primary biliary cholangitis in Northwest Italy followed up for up to 30 years

Objective: Primary biliary cholangitis (PBC) is a rare chronic autoimmune cholangiopathy, characterized by a variable course and response to treatment. We aimed to describe long-term outcomes of PBC patients referred to three academic centres in Northwest Italy. Methods: This is an ambispective cohort study of PBC patients (retrospective component: diagnosis before 1 January 2019; prospective component: thereafter), including 302 patients: 101 (33%) followed up in Novara, 86 (28%) in Turin, 115 (38%) in Genoa. Clinical features at diagnosis, biochemical response to therapy and survival were analyzed. Results: Among the 302 patients (88% women, median age 55 years, median follow-up 75 months), alkaline phosphatase (ALP) levels significantly decreased during treatment with ursodeoxycholic acid (UDCA, P < 0.0001) and obeticholic acid (P < 0.0001). At multivariate analysis, ALP at diagnosis was predictive of 1-year biochemical response to UDCA [odds ratio 3.57, 95% confidence interval (CI) 1.4-9, P < 0.001]. Estimated median survival free of liver transplantation and hepatic complications was 30 years (95% CI 19-41). Bilirubin level at diagnosis was the only independent risk factor for the combined outcome of death, transplantation or hepatic decompensation (hazard ratio, 1.65, 95% CI 1.66-2.56, P = 0.02). Patients presenting with total bilirubin at diagnosis ≥0.6 times the upper normal limit (ULN) had a significantly lower 10-year survival compared to those with bilirubin <0.6 times ULN (63% vs. 97%, P < 0.0001). Conclusion: In PBC, both short-term response to UDCA and long-term survival can be predicted by simple conventional biomarkers of disease severity, obtained at diagnosis

Observations of Forbush Decreases of Cosmic-Ray Electrons and Positrons with the Dark Matter Particle Explorer

The Forbush decrease (FD) represents the rapid decrease of the intensities of charged particles accompanied with the coronal mass ejections or high-speed streams from coronal holes. It has been mainly explored with the ground-based neutron monitor network, which indirectly measures the integrated intensities of all species of cosmic rays by counting secondary neutrons produced from interaction between atmospheric atoms and cosmic rays. The space-based experiments can resolve the species of particles but the energy ranges are limited by the relatively small acceptances except for the most abundant particles like protons and helium. Therefore, the FD of cosmic-ray electrons and positrons have just been investigated by the PAMELA experiment in the low-energy range (&lt;5 GeV) with limited statistics. In this paper, we study the FD event that occurred in 2017 September with the electron and positron data recorded by the Dark Matter Particle Explorer. The evolution of the FDs from 2 GeV to 20 GeV with a time resolution of 6 hr are given. We observe two solar energetic particle events in the time profile of the intensity of cosmic rays, the earlier, and weaker, one has not been shown in the neutron monitor data. Furthermore, both the amplitude and recovery time of fluxes of electrons and positrons show clear energy dependence, which is important in probing the disturbances of the interplanetary environment by the coronal mass ejections

Determinants of worse liver‐related outcome according to HDV infection among HBsAg positive persons living with HIV: Data from the ICONA cohort

Objectives: We aimed to study hepatitis D virus (HDV) prevalence and risk of progression to severe liver-related events (SLRE) in HBsAg positive people living with HIV (PLWH) in Italy; role of HDV-RNA copy levels, HCV coinfection and nadir CD4 counts were also investigated.Methods: People living with HIV (PLWH) from Italian Foundation cohort Naive antiretrovirals (ICONA) with available HBsAg and HDV Ab were enrolled. HBsAg, HDV Ab, HDV-RNA and HDV genotypes were tested. Primary end-point: time from first HDV screening to Severe Liver Related Events (SLRE: decompensated cirrhosis, liver transplantation, HCC). Fine-grey regression models were used to evaluate the association of HDV Ab, HDV-RNA, HDV/HCV coinfection, CD4 nadir and outcome. Secondary end-points: time to SLRE or death; HDV Ab and HDV-RNA prevalence.Results: A total of 152/809 (18.8%) HBsAg positive PLWH showed HDV Ab reactivity; 63/93 (67.7%) were HDV-RNA positive. Being male, persons who inject drugs (PWID), HCV Ab positive, with FIB-4 &gt; 3.25 were independent factors of HDV Ab positivity. In a median follow-up of 5 years, 37 PLWH (4.1% at 5-year) developed SLRE and 97 (12.0%) reached the SLRE or death end-point. HDV-RNA positive (independently from HDV-RNA copy level) PLWH had a 4.6-fold (95%CI 2.0-10.5) higher risk of SLRE than HDV negatives. PLWH positive for both HCV Ab and HDV Ab showed the highest independent risk of SLRE (ASHR: 11.9, 95%CI: 4.6-30.9 vs. HCV neg/HDV neg). Nadir CD4 &lt; 200/mL was associated with SLRE (ASHR: 3.9, 95% 1.0-14.5).Conclusions: One-fifth of the HBsAg positive PLWH harbour HDV infection, and are at high risk of progression to advanced liver disease. HCV contributes to worse outcomes. This population needs urgently effective treatments

Mitochondrial DNA Copy Number in Peripheral Blood Is Reduced in Type 2 Diabetes Patients with Polyneuropathy and Associated with a MIR499A Gene Polymorphism.

Our aim was to evaluate in a cohort of 125 Italian patients with type 2 diabetes (T2D), who underwent neurological evaluation, the possible differences in the number of mitochondrial DNA copies (mtDNA) comparing positive and negative patients for cardiovascular autonomic neuropathy (CAN) or diabetic peripheral neuropathy (DPN) and comparing them with healthy controls. We also investigated a possible correlation of the number of mtDNA copies with the polymorphism rs3746444 of the MIR499A. T2D patients show a decrease in the number of mtDNA copies compared to healthy controls (p = 2 × 10-10). Dividing the T2D subjects by neurological evaluation, we found a significant mtDNA decrease in patients with DPN compared with those without (p = 0.02), while no differences were observed between subjects with and without CAN. Furthermore, the homozygous variant genotype for the polymorphism rs3746444 of MIR499A correlates with a decrease in the number of mtDNA copies, particularly in T2D patients (p = 0.009). Our data show a decrease in the number of mtDNA copies in subjects with T2D and suggest that this decrease is more evident in patients who develop DPN. Furthermore, the association of the variant allele of MIR499A with the number of mtDNA copies allows us to hypothesize a possible effect of this polymorphism in oxidative stress

Spleen stiffness measurement predicts decompensation and rules out high-risk oesophageal varices in primary biliary cholangitis

Background &amp; Aims: Primary biliary cholangitis (PBC) may lead to portal hypertension (PH). Spleen stiffness measurement (SSM) by vibration-controlled transient elastography accurately predicts PH. We aimed to assess SSM role in stratifying the risk of liver decompensation in PBC. Methods: In this monocentric, prospective, cross-sectional study, we included 114 patients with PBC who underwent liver stiffness measurement (LSM) and SSM. In total, 78 and 33 patients underwent two and three sequential vibration-controlled transient elastography examinations, respectively (longitudinal study). Screening for high-risk oesophageal varices by oesophagogastroduodenoscopy was performed according to guidelines and proposed to all patients with SSM >40 kPa. Results: Among the 114 patients, 20 (17%) had LSM ≥10 kPa, whereas 17 (15%) had SSM >40 kPa. None of the patients with SSM ≤40 kPa had high-risk oesophageal varices, compared with three of 14 patients with SSM >40 kPa (21%; three refused endoscopy); any-size oesophageal varices were found in nine of 14 patients (64%). During a median follow-up of 15 months (IQR 10–31 months), five (4%) patients developed liver decompensation. The probability of liver decompensation was significantly higher among patients with both LSM ≥10 kPa and SSM >40 kPa: 41% at 24 months vs. 0% in other patient groups (i.e. LSM 40 kPa) (p <0.0001). Among the 78 patients undergoing longitudinal evaluation, four of nine patients (44%) with SSM increase during follow-up experienced liver decompensation, whereas none of those with stable LSM and SSM had liver decompensation. Conclusions: Both LSM and SSM predict liver decompensation in patients with PBC. SSM ≤40 kPa rules out high-risk oesophageal varices and might be used in combination with LSM to improve the prediction of PH-related complications. Impact and implications: Spleen stiffness measurement by vibration-controlled transient elastography accurately predicts portal hypertension in patients with chronic viral hepatitis. The present study is the first to demonstrate that in primary biliary cholangitis the combination of liver stiffness and spleen stiffness measurement can significantly improve risk stratification by predicting liver decompensation. Moreover, when spleen stiffness is combined with liver stiffness measurement and platelet count, it aids in identifying individuals with a low probability of having high-risk oesophageal varices, thereby allowing the avoidance of unnecessary endoscopy examinations. Further validation of our results in larger cohorts of patients with primary biliary cholangitis is needed to implement spleen stiffness measurement in clinical practice