Effect of CB1 Receptor Deficiency on Mitochondrial Quality Control Pathways in Gastrocnemius Muscle

This study aims to explore the complex role of cannabinoid type 1 receptor (CB1) signaling in the gastrocnemius muscle, assessing physiological processes in both CB1+/+ and CB1-/- mice. The primary focus is to enhance our understanding of how CB1 contributes to mitochondrial homeostasis. At the tissue level, CB1-/- mice exhibit a substantial miRNA-related alteration in muscle fiber composition, characterized by an enrichment of oxidative fibers. CB1 absence induces a significant increase in the oxidative capacity of muscle, supported by elevated in-gel activity of Complex I and Complex IV of the mitochondrial respiratory chain. The increased oxidative capacity is associated with elevated oxidative stress and impaired antioxidant defense systems. Analysis of mitochondrial biogenesis markers indicates an enhanced capacity for new mitochondria production in CB1-/- mice, possibly adapting to altered muscle fiber composition. Changes in mitochondrial dynamics, mitophagy response, and unfolded protein response (UPR) pathways reveal a dynamic interplay in response to CB1 absence. The interconnected mitochondrial network, influenced by increased fusion and mitochondrial UPR components, underlines the dual role of CB1 in regulating both protein quality control and the generation of new mitochondria. These findings deepen our comprehension of the CB1 impact on muscle physiology, oxidative stress, and MQC processes, highlighting cellular adaptability to CB1-/-. This study paves the way for further exploration of intricate signaling cascades and cross-talk between cellular compartments in the context of CB1 and mitochondrial homeostasis.

Prevalence and clinical associations of ultrasound-confirmed enthesitis in systemic lupus erythematosus

OBJECTIVES

To assess the prevalence of US-confirmed enthesitis in a cohort of patients with SLE and to analyse the clinical associations to enthesitis during the course of SLE.

METHODS

In a retrospective analysis of the SLE cohort of the Lupus Unit of the Careggi University Hospital, US examinations of SLE patients presenting with tender and/or swollen joints were retrieved to assess the presence of enthesitis. Patients with US-proven enthesitis were compared with SLE controls with tender and/or swollen joints who showed no US evidence of enthesitis. Clinical and laboratory features were compared at disease onset and during follow-up.

RESULTS

A total of 400 patients fulfilling EULAR/ACR classification criteria for SLE were assessed. Of these, 106 underwent articular US examination. Evidence of enthesitis was found in 31/106 (29.2%) patients. Seventy-one patients without US-enthesitis were included as controls; four were excluded due to lack of follow-up data. Laboratory and clinical features were comparable between cases and controls at disease onset. Throughout a median follow-up of 10.0 (interquartile range [IQR] 8.3-23.3) years for cases and 12.4 (IQR 7.2-13.3) years for controls, patients with enthesitis were less likely to develop renal involvement (22.6% vs 46.5%, P = 0.028) and failed B cell depletion more frequently (75.0% vs 0%).

CONCLUSION

In SLE patients with clinically active joints, US-proven enthesitis is a fairly common finding. Enthesitis in SLE could be the hallmark of a distinct disease phenotype with less renal involvement, more arthritis and low response to anti-CD 20 therapy, potentially requiring a tailored treatment.

Effects of Olea europaea L. Polyphenols on the Animal Welfare and Milk Quality in Dairy Cows

Here, we evaluated the effect of dietary supplementation with an Olea europaea L. extract on the animal welfare and milk quality of dairy cows. Thirty Italian Holstein-Friesian dairy cows in the mid-lactation phase (90 to 210 days) were blocked into experimental groups based on parity class (namely, primiparous (P) (n = 10), secondiparous (S) (n = 10) and pluriparous (PL) (n = 10)) and received, for 60 days, Phenofeed Dry® at 500 mg/cow/day. Milk and blood samples were collected before the start of the treatment (T0), subsequently every 15 days (T1-T4) and at 45 days after the end of treatment (T5). In the serum, glucose and triglycerides, stress, the thyroid, lactation and sex hormones were measured; in the milk, lysozyme content as well as the fatty acid profile were assessed. In the whole animal, the enriched feed helped to maintain hormonal parameters in the physiological range while producing hypoglycemic (T4 vs. T0, for P and PL p < 0.001) and hypolipidemic effects (T4 vs. T0, for P p < 0.001 and for PL p < 0.01). At the milk level, it resulted in a reduction in total fat (T5 vs. T0, for P, S and PL p < 0.001) and in the saturated fatty acids (SFAs)/monounsaturated fatty acids (MUFAs) ratio paralleled by an increase in polyunsaturated fatty acids (PUFAs) (T5 vs. T0, for P, S and PL p < 0.001), protein content (lysozyme (T4 vs. T0, for P and PL p < 0.001)) and lactose (T5 vs. T0, for P, S and PL p < 0.001). Thus, the inclusion of natural bioactive molecules such as O. europaea L. polyphenols in the dairy cow diet may help to improve animal welfare and milk quality.

Physiological Approaches Targeting Cellular and Mitochondrial Pathways Underlying Adipose Organ Senescence

The adipose organ is involved in many metabolic functions, ranging from the production of endocrine factors to the regulation of thermogenic processes. Aging is a natural process that affects the physiology of the adipose organ, leading to metabolic disorders, thus strongly impacting healthy aging. Cellular senescence modifies many functional aspects of adipose tissue, leading to metabolic alterations through defective adipogenesis, inflammation, and aberrant adipocytokine production, and in turn, it triggers systemic inflammation and senescence, as well as insulin resistance in metabolically active tissues, leading to premature declined physiological features. In the various aging fat depots, senescence involves a multiplicity of cell types, including mature adipocytes and immune, endothelial, and progenitor cells that are aging, highlighting their involvement in the loss of metabolic flexibility, one of the common features of aging-related metabolic disorders. Since mitochondrial stress represents a key trigger of cellular senescence, and senescence leads to the accumulation of abnormal mitochondria with impaired dynamics and hindered homeostasis, this review focuses on the beneficial potential of targeting mitochondria, so that strategies can be developed to manage adipose tissue senescence for the treatment of age-related metabolic disorders.

Exercise Equals the Mobilization of Visceral versus Subcutaneous Adipose Fatty Acid Molecules in Fasted Rats Associated with the Modulation of the AMPK/ATGL/HSL Axis

Combining exercise with fasting is known to boost fat mass-loss, but detailed analysis on the consequential mobilization of visceral and subcutaneous WAT-derived fatty acids has not been performed. In this study, a subset of fasted male rats (66 h) was submitted to daily bouts of mild exercise. Subsequently, by using gas chromatography-flame ionization detection, the content of 22 fatty acids (FA) in visceral (v) versus subcutaneous (sc) white adipose tissue (WAT) depots was compared to those found in response to the separate events. Findings were related to those obtained in serum and liver samples, the latter taking up FA to increase gluconeogenesis and ketogenesis. Each separate intervention reduced scWAT FA content, associated with increased levels of adipose triglyceride lipase (ATGL) protein despite unaltered AMP-activated protein kinase (AMPK) Thr172 phosphorylation, known to induce ATGL expression. The mobility of FAs from vWAT during fasting was absent with the exception of the MUFA 16:1 n-7 and only induced by combining fasting with exercise which was accompanied with reduced hormone sensitive lipase (HSL) Ser563 and increased Ser565 phosphorylation, whereas ATGL protein levels were elevated during fasting in association with the persistently increased phosphorylation of AMPK at Thr172 both during fasting and in response to the combined intervention. As expected, liver FA content increased during fasting, and was not further affected by exercise, despite additional FA release from vWAT in this condition, underlining increased hepatic FA metabolism. Both fasting and its combination with exercise showed preferential hepatic metabolism of the prominent saturated FAs C:16 and C:18 compared to the unsaturated FAs 18:1 n-9 and 18:2 n-6:1. In conclusion, depot-specific differences in WAT fatty acid molecule release during fasting, irrelevant to their degree of saturation or chain length, are mitigated when combined with exercise, to provide fuel to surrounding organs such as the liver which is correlated with increased ATGL/ HSL ratios, involving AMPK only in vWAT.

Chronic Exposure to Chlorpyrifos Damages Thyroid Activity and Imbalances Hepatic Thyroid Hormones Signaling and Glucose Metabolism: Dependency of T3-FOXO1 Axis by Hyperglycemia

Early life exposure to Endocrine Disruptor Chemicals (EDCs), such as the organophosphate pesticide Chlorpyrifos (CPF), affects the thyroid activity and dependent process, including the glucose metabolism. The damage of thyroid hormones (THs) as a mechanism of action of CPF is underestimated because the studies rarely consider that TH levels and signaling are customized peripherally. Here, we investigated the impairment of metabolism/signaling of THs and lipid/glucose metabolism in the livers of 6-month-old mice, developmentally and lifelong exposed to 0.1, 1, and 10 mg/kg/die CPF (F1) and their offspring similarly exposed (F2), analyzing the levels of transcripts of the enzymes involved in the metabolism of T3 (Dio1), lipids (Fasn, Acc1), and glucose (G6pase, Pck1). Both processes were altered only in F2 males, affected by hypothyroidism and by a systemic hyperglycemia linked to the activation of gluconeogenesis in mice exposed to 1 and 10 mg/kg/die CPF. Interestingly, we observed an increase in active FOXO1 protein due to a decrease in AKT phosphorylation, despite insulin signaling activation. Experiments in vitro revealed that chronic exposure to CPF affected glucose metabolism via the direct modulation of FOXO1 activity and T3 levels in hepatic cells. In conclusion, we described different sex and intergenerational effects of CPF exposure on the hepatic homeostasis of THs, their signaling, and, finally, glucose metabolism. The data points to FOXO1-T3-glucose signaling as a target of CPF in liver.

Serum Interleukin-36 α as a Candidate Biomarker to Distinguish Behçet's Syndrome and Psoriatic Arthritis

Behçet's syndrome (BS) is a rare systemic vasculitis characterized by different clinical manifestations. As no specific laboratory tests exist, the diagnosis relies on clinical criteria, and the differential diagnosis with other inflammatory diseases can be challenging. Indeed, in a relatively small proportion of patients, BS symptoms include only mucocutaneous, articular, gastrointestinal, and non-typical ocular manifestations, which are frequently found also in psoriatic arthritis (PsA). We investigate the ability of serum interleukin (IL)-36α-a pro-inflammatory cytokine involved in cutaneous and articular inflammatory diseases-to differentiate BS from PsA. A cross-sectional study was performed on 90 patients with BS, 80 with PsA and 80 healthy controls. Significantly lower IL-36α concentrations were found in patients with BS as compared to PsA, although in both groups IL-36α was significantly increased compared to healthy controls. An empirical cut-off of 420.6 pg/mL displayed a specificity of 0.93, with a sensitivity of 0.70 (AUC 0.82) in discriminating PsA from BS. This cut-off displayed a good diagnostic performance also in BS patients lacking highly specific BS manifestations. Our results indicate that IL-36α might be involved in the pathogenesis of both BS and PsA, and might be a candidate biomarker to support the differential diagnosis of BS.

Non-anti TNFα biologic agents for non-infectious uveitis associated with systemic inflammatory diseases: a systematic review

INTRODUCTION

Non-infectious uveitis related to systemic inflammatory diseases represents a leading cause of blindness. Anti-TNFα agents are the first-line biologic therapy after traditional immunosuppressants, both for the control of ocular and systemic involvement. However, a subgroup of patients fails anti-TNFα agents, due to primary inefficacy, loss of efficacy or adverse events.

AREAS COVERED

This systematic review summarizes current evidence on the efficacy and safety of non-anti-TNFα biologics in adult patients with non-infectious uveitis associated with systemic inflammatory diseases. The systematic review of PubMed and Embase yielded 3663 records, from which 16 studies were included (13 non-controlled, 3 controlled trials). Most studies focused on Behçet's syndrome (BS) and juvenile idiopathic arthritis (JIA) and assessed the efficacy of tocilizumab (n=11), rituximab (n=3), secukinumab (n=1), or anakinra/canakinumab (n=1). A body of evidence supports the use of tocilizumab BS and JIA-associated uveitis, for improving visual acuity, reducing central macular thickness, inducing ocular remission, and sparing corticosteroids. Preliminary data suggest that rituximab may represent a valid alternative, particularly in JIA, while anakinra/canakinumab might play a role in BS-associated uveitis. Conversely, the role of secukinumab appears limited.

EXPERT OPINION

Current evidence encourages further investigations on the efficacy and safety of non-anti-TNFα agents in non-infectious non-idiopathic uveitis.

Behçet syndrome in children and adults: discovering similarities and differences by a comparative study

OBJECTIVE

Behçet's syndrome (BS) is a rare disorder with a relapsing-remitting course. Clinical variance across geographical regions and different age groups has been observed. This study matched the demographic, clinical and treatment features of adult- and juvenile-onset BS in the Italian population.

METHODS

Two clinical databases of BS patients were compared. The paediatric BS database was collected at the Meyer Children's Hospital, Florence, while the adult BS database was collected at the Careggi University Hospital, Florence.

RESULTS

A familiar predisposition for BS was significantly more frequent in the paediatric cohort (3/33 vs 1/165, P = 0.015). No difference emerged in terms of prevalence of HLA-B51 positivity. The proportion of patients meeting the revised ICBD and/or the ISG criteria at BS diagnosis was comparable in the two cohorts. No significant difference emerged between the two cohorts in terms of muco-cutaneous, ocular and neurological involvement, and gastrointestinal symptoms. Articular manifestations resulted as more common in the paediatric cohort, whereas venous vascular events were more frequent in the adult cohort. Regarding treatment strategy, paediatric patients more frequently received no treatment or corticosteroid monotherapy. Conversely, the use of DMARDs, both traditional and biologic, was significantly higher in the adult cohort.

CONCLUSION

Remarkable differences between juvenile-onset and adult-onset BS, both in terms of gender, familiar predisposition and clinical manifestations have been observed and a different therapeutic approach in the real clinical practice of the two settings emerged. Prospective, comparison studies with a longer follow-up are encouraged to provide further data about the disease course for juvenile- and adult-onset BS.

Evidence of subclinical atherosclerosis in eosinophilic granulomatosis with polyangiitis

OBJECTIVES

Patients affected by eosinophilic granulomatosis with polyangiitis (EGPA) display an increased risk of atherothrombotic events compared with the general population. An increased frequency of subclinical markers of atherosclerosis has been observed in other ANCA-associated vasculitis, but no specific study focused on EGPA. We therefore evaluated subclinical atherosclerosis in EGPA patients and in a control population.

METHODS

Forty EGPA patients and 80 controls matched by age, sex and traditional cardiovascular risk factors underwent sonographic assessment of common carotid artery (CCA) intima-media thickness (IMT). The presence of plaques of the CCA was also investigated. The correlation between CCA-IMT and clinical and laboratory features was also assessed.

RESULTS

Median CCA-IMT was significantly higher in EGPA patients compared with controls (P = 0.002). Also, the proportion of subjects with increased CCA-IMT and with presence of plaques was significantly higher among EGPA patients (P < 0.001 for both). Moreover, within the EGPA cohort, CCA-IMT tended to increase with disease duration (P = 0.034) and corticosteroid cumulative dose (P = 0.004). No significant associations were found between CCA-IMT, ANCA status, other clinical features and therapeutic regimens. Notably, the prevalence of traditional cardiovascular risk factors was comparable in patients with vs without an increased CCA-IMT.

CONCLUSION

Ultrasound markers of subclinical atherosclerosis are increased in EGPA patients as compared with controls, independently of traditional cardiovascular risk factors.

Magnetic resonance imaging as a structural refinement to the American College of Rheumathology clinical classification criteria for knee osteoarthritis

OBJECTIVE

To evaluate if fulfilment of the definition of osteoarthritis (OA) based on the American College of Rheumatology (ACR) clinical criteria corresponds to pathological knee findings evaluated by magnetic resonance imaging (MRI). To evaluate if any such criteria is associated with a specific MRI pattern.

METHODS

Forty-six consecutive patients aged 50 years or more referred by their general practitioners (GPs) to a radiology department because of non-traumatic knee pain underwent MRI using a dedicated low field (0.2 T) machine.

RESULTS

MRI results were compared against the ACR criteria for knee OA. Patients with knee pain fulfilling the ACR criteria showed more severe synovial fluid effusion (OR 6.2, 95% CI 2.02 to 19.1), cartilage lesions in the medial area (OR 2.4, 95% CI 1.2 to 5) and higher mean number of osteophytes (OR 2.3, 95% CI 1.1 to 4.5). The association between single criteria and MRI features was more difficult to establish. Nonetheless, crepitus at joint movement was associated with synovial fluid effusion (p=0.02); bone enlargement was more frequent in patients with lesions of the posterior cruciate ligament (p=0.0001); no palpable warmth was associated with cartilage lesions (p=0.02), and morning stiffness shorter than 30 minutes was associated with the surface of bone edema (p=0.02).

CONCLUSIONS

The ACR clinical criteria identify patients showing the most important features of OA. The association between individual clinical ACR criteria and OA pathology depicted by MRI may be difficult to explain on the basis of anatomical changes and needs further evaluation.

Depression and Anxiety Are Associated With Worse Subjective and Functional Baseline Scores in Patients With Frozen Shoulder Contracture Syndrome: A Systematic Review

Purpose

To investigate whether psychological factors, such as avoidance behavior, fear, pain catastrophization, kinesiophobia, anxiety, depression, optimism, and expectation are associated with different subjective and functional baseline scores in patients with frozen shoulder contracture syndrome (FSCS).

Methods

Searches were conducted in MEDLINE, Cochrane Library (CENTRAL Database), PEDro, Pubpsych, and PsychNET.APA without restrictions applied to language, date, or status of publication. Two authors reviewed study titles, abstract, and full text based on the following inclusion criteria: adult population (≥ 30 < 70 years old) with FSCS.

Results

Seven hundred and seventy-six records were included by the search strategies. After title final screening, 6 studies were included for the qualitative synthesis. Psychological features investigated were anxiety, depression, pain-related fear, pain catastrophizing, and pain self-efficacy; reported outcomes included pain, function, disability, quality of life, and range of motion. Data suggest that anxiety and depression impact self-assessed function, pain, and quality of life. There is no consensus on the correlation between psychological variables and range of motion. Associations were suggested between pain-related fear, pain-related beliefs, and pain-related behavior and perceived arm function; pain-related conditions showed no significant correlation with range of motion and with perceived stiffness at baseline.

Conclusion

Scores traditionally thought to assess physical dimensions like shoulder pain, disability, and function seem to be influenced by psychological variables. In FSCS patients, depression and anxiety were associated with increased pain perception and decreased function and quality of life at baseline. Moreover, pain-related fear and catastrophizing seem to be associated with perceived arm function.

Gut Microbiota and Associated Mucosal Immune Response in Eosinophilic Granulomatosis with Polyangiitis (EGPA)

Eosinophilic granulomatosis with polyangiitis (EGPA) is an anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis. A genome-wide association study showed a correlation between ANCA-negative EGPA and variants of genes encoding proteins with intestinal barrier functions, suggesting that modifications of the mucosal layer and consequent gut dysbiosis might be involved in EGPA pathogenesis. Here, we characterized the gut microbiota (GM) composition and the intestinal immune response in a cohort of EGPA patients. Faeces from 29 patients and 9 unrelated healthy cohabitants were collected, and GM and derived metabolites’ composition were compared. Seven intestinal biopsies from EGPA patients with gastrointestinal manifestations were analysed to assess the T-cell distribution and its correlation with GM and EGPA clinical and laboratory features. No significant differences in GM composition, nor in the total amount of faecal metabolites, emerged between patients and controls. Nevertheless, differences in bacterial taxa abundances and compositional GM-derived metabolites profile were observed. Notably, an enrichment of potential pathobionts (Enterobacteriacee and Streptococcaceae) was found in EGPA, particularly in patients with active disease, while lower levels were found in patients on immunosuppression, compared with non-immunosuppressed ones. Significantly lower amounts of hexanoic acid were found in patients, compared to controls. The analysis of the immune response in the gut mucosa revealed a high frequency of IFN-γ/IL-17-producing T lymphocytes, and a positive correlation between EGPA disease activity and intestinal T-cell levels. Our data suggest that an enrichment in potential intestinal pathobionts might drive an imbalanced inflammatory response in EGPA.

Ablation of uncoupling protein 3 affects interrelated factors leading to lipolysis and insulin resistance in visceral white adipose tissue

The physiological role played by uncoupling protein 3 (UCP3) in white adipose tissue (WAT) has not been elucidated so far. In the present study, we evaluated the impact of the absence of the whole body UCP3 on WAT physiology in terms of ability to store triglycerides, oxidative capacity, response to insulin, inflammation, and adipokine production. Wild type (WT) and UCP3 Knockout (KO) mice housed at thermoneutrality (30°C) have been used as the animal model. Visceral gonadic WAT (gWAT) from KO mice showed an impaired capacity to store triglycerides (TG) as indicated by its lowered weight, reduced adipocyte diameter, and higher glycerol release (index of lipolysis). The absence of UCP3 reduces the maximal oxidative capacity of gWAT, increases mitochondrial free radicals, and activates ER stress. These processes are associated with increased levels of monocyte chemoattractant protein-1 and TNF-α. The response of gWAT to in vivo insulin administration, revealed by (ser473)-AKT phosphorylation, was blunted in KO mice, with a putative role played by eif2a, JNK, and inflammation. Variations in adipokine levels in the absence of UCP3 were observed, including reduced adiponectin levels both in gWAT and serum. As a whole, these data indicate an important role of UCP3 in regulating the metabolic functionality of gWAT, with its absence leading to metabolic derangement. The obtained results help to clarify some aspects of the association between metabolic disorders and low UCP3 levels.

Pax8 and Nkx2-1 haploinsufficiencies differentially affect liver metabolic pathways

Thyroid dysfunctions are associated with liver diseases ranging, in severity, from insulin resistance (IR) to hepatocellular carcinoma. The pathogenic mechanisms appear complex and are not attributable, exclusively, to the impaired thyroid hormone (TH) signalling. Using a mouse model of human congenital hypothyroidism, young double heterozygote for both NK2 homeobox 1 (Nkx2-1)- and Paired box 8 (Pax8)-null mutations (DHTP) mice, and single heterozygous Pax8+/- and Nkx2-1+/- mice, we studied the liver pathways, the endocrine and metabolic factors affected in conditions of different dysthyroidisms. Young Nkx2-1+/- females displayed a slight hyperthyroidism and, in liver, increased TH signalling (i.e. increased expression of Dio1 and Trβ1) and lipogenic gene expression, with triglycerides accumulation. Hypothyroid DHTP and euthyroid Pax8+/- females shared liver and skeletal muscle IR and hepatic hypothyroidism (i.e. reduced expression of Mct8, Dio1 and TRβ1), activation of AKT and increased expression of glutathione peroxidase 4. Oxidative stress and reduced mitochondrial COX activity were observed in DHTP mice only. Pax8+/- females, but, unexpectedly, not DHTP ones, displayed transcriptional activation of the hepatic (and renal) gluconeogenic pathway, hypercortisolemia, fasting hyperglycaemia and hyperinsulinemia, reduced serum β-hydroxybutyrate, associated with hepatic AMPK activation. DHTP mice showed hypercholesterolemia and activation of mTOR. Collectively, the data indicate that heterozygote mutations of Pax8 and Nkx2-1 genes may produce multiple dysmetabolisms, even under systemic euthyroidism. Differential liver pathways and multiple hormonal axes are affected with implications for energy and nutrient homeostasis. The identified players may be specific target in the management of thyroid dysfunction-associated dysmetabolisms in terms of prevention/counteraction of IR, type 2 diabetes and related comorbidities.

Impact of COVID-19 and COVID-19 vaccination on high-risk patients with Antiphospholipid Syndrome: a nationwide survey

Objectives

Patients with antiphospholipid syndrome (APS) and triple-positive for antiphospholipid antibodies (aPL) are at high-risk of recurrent events. As COVID-19 and COVID-19 vaccination may induce thrombotic complications, the objective of the study was to assess the course of COVID-19 and adverse events after vaccination in these patients.

Methods

This is a nationwide multicentre survey conducted in nine APS referral centres by means of a questionnaire. Included patients are thrombotic APS with triple-positive aPL confirmed 12 weeks apart. Reference specialist physicians used a four-graded scale of severity for COVID-19 [from 0 (asymptomatic) to 3 (hospitalization in intensive care unit)] and a six-graded scale for adverse reactions to vaccination [from 0 (transient local injection site sign/symptoms) to 5 (potentially life-threatening reactions)]. Outcomes were considered within a 30-days period.

Results

Out of 161 patients interviewed, 18 (11%) had COVID-19. All of them fully recovered without any progression to severe disease nor thromboembolic event. One-hundred-forty-six patients received the first (92%) and 129 (80%) the second dose of vaccine; side effects were minimal and, in most cases, (83% after the first and 68% after the second shot) limited to a sore arm. Fifteen patients (9%) were unvaccinated. Most of them raised doubts on the need for vaccination, complained for poor safety and in general were reluctant on COVID-19 vaccination.

Conclusion

Patients with triple-positive thrombotic APS did not suffer from severe COVID-19 outcomes. Importantly, COVID-19 vaccination was well tolerated. These data may reassure patients and physicians and contribute in reducing hesitancy in unvaccinated patients.

Bioenergetic Aspects of Mitochondrial Actions of Thyroid Hormones

Much is known, but there is also much more to discover, about the actions that thyroid hormones (TH) exert on metabolism. Indeed, despite the fact that thyroid hormones are recognized as one of the most important regulators of metabolic rate, much remains to be clarified on which mechanisms control/regulate these actions. Given their actions on energy metabolism and that mitochondria are the main cellular site where metabolic transformations take place, these organelles have been the subject of extensive investigations. In relatively recent times, new knowledge concerning both thyroid hormones (such as the mechanisms of action, the existence of metabolically active TH derivatives) and the mechanisms of energy transduction such as (among others) dynamics, respiratory chain organization in supercomplexes and cristes organization, have opened new pathways of investigation in the field of the control of energy metabolism and of the mechanisms of action of TH at cellular level. In this review, we highlight the knowledge and approaches about the complex relationship between TH, including some of their derivatives, and the mitochondrial respiratory chain.

A unique circulating miRNA profile highlights thrombo-inflammation in Behçet's syndrome

Objectives

Behçet’s syndrome (BS) is a rare systemic vasculitis often complicated by thrombotic events. Given the lack of validated biomarkers, BS diagnosis relies on clinical criteria.

In search of novel biomarkers for BS diagnosis, we determined the profile of plasmatic circulating microRNAs (ci-miRNAs) in patients with BS compared with healthy controls (HCs).

Methods

ci-miRNA profile was evaluated by microarray in a screening cohort (16 patients with BS and 18 HCs) and then validated by poly(T) adaptor PCR (PTA-PCR) in a validation cohort (30 patients with BS and 30 HCs). Two disease control groups (30 patients with systemic lupus erythematosus (SLE) and 30 patients with giant cell arteritis (GCA) were also analysed.

Results

From the microarray screening, 29 deregulated (differentially expressed (DE)) human ci-miRNAs emerged. A hierarchical cluster analysis indicated that DE ci-miRNAs clearly segregated patients from controls, independently of clinical features. PTA-PCR analysis on the validation cohort confirmed the deregulation of miR-224-5p, miR-206 and miR-653-5p. The combined receiver operating characteristic (ROC) curve analyses showed that such ci-miRNAs discriminate BS from HCs (and BS with active vs inactive disease), as well as BS from patients with SLE and GCA.

The functional annotation analyses (FAAs) showed that the most enriched pathways affected by DE ci-miRNAs (ie, cell–matrix interaction, oxidative stress and blood coagulation) are related to thrombo-inflammatory mechanisms. Accordingly, the expression of the three ci-miRNAs from the validation cohort significantly correlated with leucocyte reactive oxygen species production and plasma lipid peroxidation.

Conclusions

The ci-miRNA profile identified in this study may represent a novel, poorly invasive BS biomarker, while suggesting an epigenetic control of BS-related thrombo-inflammation.

Neutrophil-mediated mechanisms of damage and in-vitro protective effect of colchicine in non-vascular Behçet's syndrome

Behçet’s syndrome (BS) is a systemic vasculitis with several clinical manifestations. Neutrophil hyperactivation mediates vascular BS pathogenesis, via both a massive reactive oxygen species (ROS) production and neutrophil extracellular traps (NETs) release. Here, we investigated neutrophil‐mediated mechanisms of damage in non‐vascular BS manifestations and explored the in‐vitro effects of colchicine in counteracting these mechanisms. NETs and intracellular ROS production was assessed in blood samples from 80 BS patients (46 with active non‐vascular BS, 34 with inactive disease) and 80 healthy controls. Moreover, isolated neutrophils were incubated for 1 h with an oxidating agent [2,2′‐azobis (2‐amidinopropane) dihydrochloride; 250 nM] and the ability of pure colchicine pretreatment (100 ng/ml) to counteract oxidation‐induced damage was assessed. Patients with active non‐vascular BS showed remarkably increased NET levels [21.2, interquartile range (IQR) = 18.3–25.9 mU/ml] compared to patients with inactive disease (16.8, IQR = 13.3–20.2 mU/ml) and to controls (7.1, IQR = 5.1–8.7 mU/ml, p < 0.001]. Also, intracellular ROS tended to increase in active BS, although not significantly. In active non‐vascular BS, NETs correlated with neutrophil ROS production (p < 0.001) and were particularly increased in patients with active mucosal (p < 0.001), articular (p = 0.004) and gastrointestinal symptoms (p = 0.006). In isolated neutrophils, colchicine significantly reduced oxidation‐induced NET production and cell apoptosis, although not via an anti‐oxidant activity. Neutrophil‐mediated mechanisms might be directly involved in non‐vascular BS, and NETs, more than ROS, might drive the pathogenesis of mucosal, articular and intestinal manifestations. Colchicine might be effective in counteracting neutrophils‐mediated damage in BS, although further studies are needed.

Comparison of treatments for the prevention of fetal growth restriction in obstetric antiphospholipid syndrome: a systematic review and network meta-analysis

Women with criteria and non-criteria obstetric antiphospholipid syndrome (APS) carry an increased risk of pregnancy complications, including fetal growth restriction (FGR). The management of obstetric APS traditionally involves clinicians, obstetricians and gynaecologists; however, the most appropriate prophylactic treatment strategy for FGR prevention in APS is still debated. We performed a systematic review and network meta-analysis (NetMA) to summarize current evidence on pharmacological treatments for the prevention of FGR in APS. We searched PubMed and Embase from inception until July 2020, for randomized controlled trials and prospective studies on pregnant women with criteria or non-criteria obstetric APS. NetMA using a frequentist framework were conducted for the primary outcome (FGR) and for secondary outcomes (fetal or neonatal death and preterm birth). Adverse events were narratively summarised. Out of 1124 citations, we included eight studies on 395 pregnant patients with obstetric APS treated with low-dose aspirin (LDA) + unfractionated heparin (UFH) (n = 132 patients), LDA (n = 115), LDA + low molecular weight heparin (n = 100), LDA + corticosteroids (n = 29), LDA + UFH + intravenous immunoglobulin (n = 7), or untreated (n = 12). No difference among treatments emerged in terms of FGR prevention, but estimates were largely imprecise, and most studies were at high/unclear risk of bias. An increased risk of fetal or neonatal death was found for LDA monotherapy as compared to LDA + heparin, and for no treatment as compared to LDA + corticosteroids. The risk of preterm birth was higher for LDA + UFH + IVIg as compared to LDA or LDA + heparin, and for LDA + corticosteroids as compared to LDA or LDA + LMWH. No treatment was associated with an increased risk of bleeding, thrombocytopenia or osteopenia.

Sample-Pooling Strategy for SARS-CoV-2 Detection among Students and Staff of the University of Sannio

Since the beginning of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic, it has been clear that testing large groups of the population was the key to stem infection and prevent the effects of the coronavirus disease of 2019, mostly among sensitive patients. On the other hand, time and cost-sustainability of virus detection by molecular analysis such as reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) may be a major issue if testing is extended to large communities, mainly asymptomatic large communities. In this context, sample-pooling and test grouping could offer an effective solution. Here we report the screening on 1195 oral-nasopharyngeal swabs collected from students and staff of the Università degli Studi del Sannio (University of Sannio, Benevento, Campania, Italy) and analyzed by an in-house developed multiplex RT-qPCR for SARS-CoV-2 detection through a simple monodimensional sample pooling strategy. Overall, 400 distinct pools were generated and, within 24 h after swab collection, five positive samples were identified. Out of them, four were confirmed by using a commercially available kit suitable for in vitro diagnostic use (IVD). High accuracy, sensitivity and specificity were also determined by comparing our results with a reference IVD assay for all deconvoluted samples. Overall, we conducted 463 analyses instead of 1195, reducing testing resources by more than 60% without lengthening diagnosis time and without significant losses in sensitivity, suggesting that our strategy was successful in recognizing positive cases in a community of asymptomatic individuals with minor requirements of reagents and time when compared to normal testing procedures.

Drug-specific Treg cells are induced during desensitization procedure for rituximab and tocilizumab in patients with anaphylaxis

Biologic agents (BA) are able to induce an adaptive immune response in a proportion of exposed patients with the onset of anti-drug antibodies (ADA), which are usually responsible for hypersensitivity reactions (HR). Drug desensitization (DD) for BA allows transient clinical tolerance to the drug in reactive patients. The paper aimed to analyse the modification of drug-specific immune responses along DD in two patients with previous ADA-mediated HR (anaphylaxis) to rituximab and tocilizumab. The in vivo and in vitro assays of humoral and cellular response to drugs were carried out in a longitudinal manner throughout the DD cycles. We observed a progressive decrease of the pre-procedure ADA titer with negativization during the DD cycles in both patients. The monitoring of the drug-specific effector cell response showed the decrease in the BA-induced proliferation, while T cell response to unrelated antigens resulted unmodified along the DD cycles. Lastly, the increase of circulating drug-specific Treg cells mainly producing IL-35 were shown during the DD treatment. This study provides evidence that DD treatment to two BA inhibits humoral and cellular anti-drug response by increasing regulatory T cells and cytokines in an antigen-restricted manner. These modifications could contribute to the safety of the procedure.

POS1212 SARS-CoV-2 INFECTION AMONG PATIENTS WITH BEHÇET’S SYNDROME

Background:

Studies on SARS-Cov-2 in Behçet’s syndrome (BS) patients are limited to two small case series from European centres.[1,2]

Objectives:

We aimed to assess the prevalence of SARS-CoV-2 infection among Italian BS patients referring to Careggi University Hospital (Florence, Italy) and to evaluate the possible association between BS disease activity and treatment and the risk of Sars-CoV-2 infection among patients with BS.

Methods:

A survey was conducted among 335 subjects diagnosed with BS and followed at Careggi University Hospital. Moreover, we conducted a case-control study. Cases were described in term of SARS-CoV-2 manifestation and prognosis, changes in disease activity, and in pharmacological therapies. Sars-CoV-2 negative controls matched 1:3 by sex, age and disease duration ± 5 years were randomly selected.

Results:

Out of 335 BS patients, 12 declared to have/have had SARS-CoV-2 infection (3.6%). Eight were females (median age of 40 years), with a median duration of BS disease of 6 years; five had active disease. Nine patients reported fever, 9 myalgia/arthralgia, 5 gastrointestinal symptoms, 5 anosmia/ageusia, 5 cough, 3 headache, 3 fatigue, 2 breathlessness, panic attacks and dizziness (one each). Before infection, patients were treated with corticosteroids, colchicine, hydroxychloroquine (HCQ), traditional DMARDs [azathioprine (n patients = 4), methotrexate (n=1)], and biologics DMARDs [adalimumab (n=6), infliximab (n=2), secukinumab (n=1), and canakinumab (n=1)]. Therapy was suspended for a median time of 33 days in 9patients and resumed after a median time of 5 days from negativation. Regarding SARS-CoV-2 treatment, most patients started or increased corticosteroids, whereas heparin and antipyretic drugs were used in 4 and 5 patients, respectively. Cases were comparable to controls in terms of disease manifestations, activity, and immunomodulating therapy, with the only exception of corticosteroids, whose daily dose was significantly higher in cases (Table 1).

Conclusion:

Prevalence of SARS-CoV-2 infection among Italian BS patients is 3.6%, similarly to the Italian general population (4.2%). Disease activity at time of infection was not associated with an increased risk of SARS-CoV-2 infection. Most patients interrupted biologic DMARDs. However, use of DMARDs, seemed not to be associated with an increased risk of SARS-CoV-2 infection, while higher doses of corticosteroids resulted to be more common among patients with SARS-CoV-2 infection as compared to controls. No patient required hospitalization or died. Our experience shows encouraging data about BS patients who do not appear be at greater risk of SARS-CoV-2 infection or complications than the general population.

References:

[1]Espinosa et al. COVID-19 and Behçet’s disease: clinical case series. Ann Rheum Dis. 2020

[2]Yurttaş et al. Characteristics and outcomes of Behçet’s syndrome patients with Coronavirus Disease 2019: a case series of 10 patients. IEM. 2020

[3]http://www.salute.gov.it

Table 1.

Features of SARS-CoV-2+ cases and matched controls

12 SARS-CoV-2+ CASESPRE-INFECTION12 SARS-CoV-2+ CASESPOST-INFECTION36 CONTROLSp-value*Female sex8 (66.7%)24 (66.7%)Matching variableMedian age40 (IQR 31-45)40 (IQR 32-44)Matching variableMedian disease duration6 (IQR 5-9)6 (IQR 3-8)Matching variableActive disease (BDCAF≥1)5 (41.7%)4 had disease relapse24 (66.7%)0.176Immunomodulating therapyCorticosteroids –8 (66.7%)8 (66.7%)12 (33.3%)0.088Median dosage (IQR)5 (IQR 0-12.5)6 (IQR 0-15)0 (IQR 0-2.5)0.010Colchicine2 (16.7%)Continued11 (30.6%)0.469HCQ1 (8.3%)Continued1 (2.8%)0.441Traditional DMARDs5 (41.7%)1 interrupted8 (22.2%)0.263Biologic DMARDs10 (83.3%)8 interrupted27 (75%)0.705Disease involvementMucocutaneous5 (41.7%)12 (33.3%)0.731Articular5 (41.7%)4 worsened17 (47.2%)1.000Ocular02 (5.6%)n.a.Vascular00n.a.Neurological3 (25%)8 (22.2%)1.000Gastrointestinal2 (16.7%)1 worsened6 (16.7%)1.000

*p-value from Fisher exact test for unpaired data between first columns vs third columns

Disclosure of Interests:

None declared.

FC 039RENAL OUTCOME AFTER RITUXIMAB IN ADULT-ONSET IGA VASCULITIS AND CRESCENTIC IGA NEPHROPATHY: A MULTICENTRE STUDY

Background and Aims

Glucocorticoids (GC) and/or immunosuppressive agents are the mainstay of therapy for adult-onset IgA Vasculitis (IgAV), but their efficacy is often partial while their toxicity is relevant. Recently, rituximab (RTX) has been reported as a safe and effective option but only few data on renal outcome are available.1 RTX has also been used in a few cases of crescentic IgA Nephropathy (cIgAN), an IgAN subset with vasculitic lesions and poor response to conventional immunosuppressive regimens.2 We present the results of a multicentre cohort of patients with IgAV and cIgAN treated with RTX.

Method

The databases of 16 consorted European centres were investigated to screen for patients with adult-onset, biopsy-proven IgAV and cIgAN (crescents in ≥25% glomeruli and rapid eGFR worsening at presentation), who received RTX as induction therapy. We selected patients with active renal manifestations at the time of RTX. Remission was defined as a Birmingham Vasculitis Activity Score (BVAS)=0 or &lt;5 if it was due to persistent proteinuria and relapse as an increase in BVAS requiring change in immunosuppressive therapy.

Results

We identified 38 patients with IgAV and 12 patients with cIgAN who received RTX and had active renal involvement at the time of treatment. The median age at onset was 40 years (interquartile range, IQR, 25-53) and more than two-thirds of patients were male (Table 1). The median follow-up after RTX was 41 months (IQR 18-60).

Renal outcomes are reported in Table 2. At the time of treatment, 24 patients (48%) had eGFR ≥60 mL/min/1.73 m2. All had IgAV and their median BVAS was 17 (IQR 10-22). Furthermore, all had microhaematuria and proteinuria. Renal histology showed mesangial or focal endocapillary proliferation in 12/17 (71%) patients who underwent biopsy (class II-IIIA according to Pillebout3). Twenty patients (83%) achieved remission; after a median of 12 months (range 9-14), four experienced a minor relapse and one had a major relapse with significant renal disease progression. Renal function remained stable in all but two patients who developed end-stage renal disease (ESRD). Micro-haematuria subsided in 14/24 (58%) and median 24h proteinuria decreased from 1750 mg (IQR 865-3275) to 175 mg (IQR 100-800) at last follow-up (p=0.029).

Of the 26 patients with eGFR &lt;60 mL/min/1.73 m2, 14 had IgAV and 12 had cIgAN. All were biopsied and 20 (77%) had diffuse endo/extra-capillary proliferation (classes IIIB-IV). Five patients required dialysis but recovered soon after treatment start. Remission was achieved by 16/26 (61%); eight (50%) subsequently relapsed and two (12%) reached ESRD. At last follow-up, eGFR was ≥60 mL/min/1.73 m2 in 8/26 (31%), 10/26 (48%) had stable renal function as compared to the time of RTX, while 8/26 (31%) had developed ESRD. Median 24h proteinuria decreased from 3400 mg (IQR 2150-6500) to 770 mg (177-1315) (p=0.016).

Remission rate and ESRD-free survival were respectively 86% and 92% in patients with IgAV, while they were respectively 42% and 42% in cIgAN patients. Furthermore, 21/24 (87%) patients who received RTX alone or combined to glucocorticoids but not to immunosuppressive agents achieved remission and 22/24 (92%) were ESRD-free at last follow-up. Of the 26 patients receiving immunosuppressive agents, 17 (65%) obtained remission and 18 (69%) were ESRD-free at last assessment. Over the whole follow-up, only one patient reported a severe adverse effect related to RTX (pneumonia).

Conclusion

Renal involvement in adult-onset IgAV and cIgAN is frequently severe. RTX, combined or not with other immunosuppressive agents, may improve renal manifestations and is well tolerated. IgAV patients show higher remission rates and a longer ESRD-free survival as compared to cIgAN patients.

Cardiac involvement in eosinophilic granulomatosis with polyangiitis (formerly Churg-Strauss syndrome): Prospective evaluation at a tertiary referral centre

BACKGROUND

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare systemic vasculitis. Cardiac specific involvement (CSI) is caused by coronary artery vasculitis, but also by myocardial eosinophilic infiltration. To date, the prevalence of CSI associated with EGPA is unresolved. Aim of this study was to systematically assess the prevalence and clinical impact of CSI in a consecutive outpatient EGPA population.

METHODS

Between October 2018 and July 2019, we prospectively enrolled 52 consecutive EGPA patients. All underwent comprehensive evaluation including a standardized questionnaire, physical examination, 12-lead-ECG, echocardiography. Cardiac magnetic resonance and 24 h-Holter were performed as deemed clinically appropriate. Cardiac abnormalities were defined as CSI based on the likelihood of their relation to EGPA vasculitis, after exclusion of alternative diagnoses.

RESULTS

52 enrolled patients, mean age 59±1 years. Thirteen of the 52 patients (25%) were classified as CSI+. CSI was characterized by myocarditis in four patients, non-scar-related regional wall motions abnormalities (RWMA) in three, apical thrombosis in two (one also had RWMA), pericarditis in three and non-atherosclerotic coronary disease (Prinzmetal angina and coronaritis) in 2. Five (38%) of the 13 CSI+ patients, presented an apical aneurysm. Peak eosinophil count at diagnosis was higher in CSI+: 8000 /μl vs CSI-: 3000 /μl, p = 0.017. Overall, 2 patients had severe LV dysfunction, 5 required urgent hospitalization and 8 required long-term cardioactive therapy.

CONCLUSIONS

CSI was present in one-quarter of patients, often associated with high peak eosinophils. Myocarditis, RWMA and apical aneurysms were the most common manifestations. Although rarely severe and life-threatening, CSI often required long-term cardioactive treatment.

The multifaceted spectrum of liver cirrhosis in older hospitalised patients: analysis of the REPOSI registry

BACKGROUND

Knowledge on the main clinical and prognostic characteristics of older multimorbid subjects with liver cirrhosis (LC) admitted to acute medical wards is scarce.

OBJECTIVES

To estimate the prevalence of LC among older patients admitted to acute medical wards and to assess the main clinical characteristics of LC along with its association with major clinical outcomes and to explore the possibility that well-distinguished phenotypic profiles of LC have classificatory and prognostic properties.

METHODS

A cohort of 6,193 older subjects hospitalised between 2010 and 2018 and included in the REPOSI registry was analysed.

RESULTS

LC was diagnosed in 315 patients (5%). LC was associated with rehospitalisation (age-sex adjusted hazard ratio, [aHR] 1.44; 95% CI, 1.10-1.88) and with mortality after discharge, independently of all confounders (multiple aHR, 2.1; 95% CI, 1.37-3.22), but not with in-hospital mortality and incident disability. Three main clinical phenotypes of LC patients were recognised: relatively fit subjects (FIT, N = 150), subjects characterised by poor social support (PSS, N = 89) and, finally, subjects with disability and multimorbidity (D&M, N = 76). PSS subjects had an increased incident disability (35% vs 13%, P < 0.05) compared to FIT. D&M patients had a higher mortality (in-hospital: 12% vs 3%/1%, P < 0.01; post-discharge: 41% vs 12%/15%, P < 0.01) and less rehospitalisation (10% vs 32%/34%, P < 0.01) compared to PSS and FIT.

CONCLUSIONS

LC has a relatively low prevalence in older hospitalised subjects but, when present, accounts for worse post-discharge outcomes. Phenotypic analysis unravelled the heterogeneity of LC older population and the association of selected phenotypes with different clinical and prognostic features.

Trial of Rivaroxaban in AntiPhospholipid Syndrome (TRAPS): Two-year outcomes after the study closure

BACKGROUND

Trial of Rivaroxaban in AntiPhospholipid Syndrome was a prospective randomized, open-label, noninferiority study conducted in 14 centers in Italy. Rivaroxaban was compared with warfarin for the prevention of thromboembolic events, major bleeding, and vascular death in high-risk, triple-positive patients with antiphospholipid syndrome.

OBJECTIVE

The aim of this paper is to report the events during the 2-year follow-up after the study closure.

METHODS

On January 28, 2018, the trial was prematurely stopped by adjudication and safety committee for an excess of events in the rivaroxaban group. Randomized patients were advised on trial results and those randomized to rivaroxaban were solicited to switch to warfarin. All 14 participating centers were asked and accepted to follow their patients for clinical events. This report describes the rate of events that occurred between January 28, 2018, and January 28, 2020.

RESULTS

Of 120 randomized patients, 115 were available for follow-up. Outcome events were two in six (33.3%) patients who remained on direct oral anticoagulants (DOACs) and six in 109 (5.7%) patients on warfarin (hazard ratio [HR] 6.9; 95% confidence interval [CI] 1.4-34.5, P = .018). The two patients on DOACs (one taking dabigatran and one taking rivaroxaban) suffered from thromboembolic events, whereas of the six patients with composite outcomes on warfarin, three had thromboembolic events (HR for thrombosis 13.3; 95% CI 2.2-79.9, P = .005).

CONCLUSION

These data further support the use of warfarin in high-risk patients with antiphospholipid syndrome.

3,5-Diiodo-L-Thyronine (T2) Administration Affects Visceral Adipose Tissue Inflammatory State in Rats Receiving Long-Lasting High-Fat Diet

3,5-diiodo-thyronine (T2), an endogenous metabolite of thyroid hormones, exerts beneficial metabolic effects. When administered to overweight rats receiving a high fat diet (HFD), it significantly reduces body fat accumulation, which is a risk factor for the development of an inflammatory state and of related metabolic diseases. In the present study, we focused our attention on T2 actions aimed at improving the adverse effects of long-lasting HFD such as the adipocyte inflammatory response. For this purpose, three groups of rats were used throughout: i) receiving a standard diet for 14 weeks; ii) receiving a HFD for 14 weeks, and iii) receiving a HFD for 14 weeks with a simultaneous daily injection of T2 for the last 4 weeks. The results showed that T2 administration ameliorated the expression profiles of pro- and anti-inflammatory cytokines, reduced macrophage infiltration in white adipose tissue, influenced their polarization and reduced lymphocytes recruitment. Moreover, T2 improved the expression of hypoxia markers, all altered in HFD rats, and reduced angiogenesis by decreasing the pro-angiogenic miR126 expression. Additionally, T2 reduced the oxidative damage of DNA, known to be associated to the inflammatory status. This study demonstrates that T2 is able to counteract some adverse effects caused by a long-lasting HFD and to produce beneficial effects on inflammation. Irisin and SIRT1 pathway may represent a mechanism underlying the above described effects.

Adaptive Thermogenesis Driving Catch-Up Fat Is Associated With Increased Muscle Type 3 and Decreased Hepatic Type 1 Iodothyronine Deiodinase Activities: A Functional and Proteomic Study

Refeeding after caloric restriction induces weight regain and a disproportionate recovering of fat mass rather than lean mass (catch-up fat) that, in humans, associates with higher risks to develop chronic dysmetabolism. Studies in a well-established rat model of semistarvation-refeeding have reported that catch-up fat associates with hyperinsulinemia, glucose redistribution from skeletal muscle to white adipose tissue and suppressed adaptive thermogenesis sustaining a high efficiency for fat deposition. The skeletal muscle of catch-up fat animals exhibits reduced insulin-stimulated glucose utilization, mitochondrial dysfunction, delayed in vivo contraction-relaxation kinetics, increased proportion of slow fibers and altered local thyroid hormone metabolism, with suggestions of a role for iodothyronine deiodinases. To obtain novel insights into the skeletal muscle response during catch-up fat in this rat model, the functional proteomes of tibialis anterior and soleus muscles, harvested after 2 weeks of caloric restriction and 1 week of refeeding, were studied. Furthermore, to assess the implication of thyroid hormone metabolism in catch-up fat, circulatory thyroid hormones as well as liver type 1 (D1) and liver and skeletal muscle type 3 (D3) iodothyronine deiodinase activities were evaluated. The proteomic profiling of both skeletal muscles indicated catch-up fat-induced alterations, reflecting metabolic and contractile adjustments in soleus muscle and changes in glucose utilization and oxidative stress in tibialis anterior muscle. In response to caloric restriction, D3 activity increased in both liver and skeletal muscle, and persisted only in skeletal muscle upon refeeding. In parallel, liver D1 activity decreased during caloric restriction, and persisted during catch-up fat at a time-point when circulating levels of T4, T3 and rT3 were all restored to those of controls. Thus, during catch-up fat, a local hypothyroidism may occur in liver and skeletal muscle despite systemic euthyroidism. The resulting reduced tissue thyroid hormone bioavailability, likely D1- and D3-dependent in liver and skeletal muscle, respectively, may be part of the adaptive thermogenesis sustaining catch-up fat. These results open new perspectives in understanding the metabolic processes associated with the high efficiency of body fat recovery after caloric restriction, revealing new implications for iodothyronine deiodinases as putative biological brakes contributing in suppressed thermogenesis driving catch-up fat during weight regain.

Absence of uncoupling protein 3 at thermoneutrality influences brown adipose tissue mitochondrial functionality in mice

The physiological role played by uncoupling protein 3 (UCP3) in brown adipose tissue (BAT) has not been fully elucidated so far. In the present study, we evaluated the impact of the absence of UCP3 on BAT mitochondrial functionality and morphology. To this purpose, wild type (WT) and UCP3 Knockout (KO) female mice were housed at thermoneutrality (30°C), a condition in which BAT contributes to energy homeostasis independently of its cold-induced thermogenic function. BAT mitochondria from UCP3 KO mice presented a lower ability to oxidize the fatty acids and glycerol-3-phosphate, and an enhanced oxidative stress as revealed by enhanced mitochondrial electron leak, lipid hydroperoxide levels, and induction of antioxidant mitochondrial enzymatic capacity. The absence of UCP3 also influenced the mitochondrial super-molecular protein aggregation, an important feature for fatty acid oxidation rate as well as for adequate cristae organization and mitochondrial shape. Indeed, electron microscopy revealed alterations in mitochondrial morphology in brown adipocytes from KO mice. In the whole, data here reported show that the absence of UCP3 results in a significant alteration of BAT mitochondrial physiology and morphology. These observations could also help to clarify some aspects of the association between metabolic disorders associated with low UCP3 levels, as previously reported in human studies.

A multicenter approach to evaluate omalizumab effectiveness in Samter's triad

Omalizumab proved to be very effective in improving control of severe atopic asthma. Many small-sized studies suggested a potential role for omalizumab in the management of aspirin-exacerbated respiratory disease. The aim of this study is to describe the effectiveness of omalizumab in a multicentre group of patients with Samter's triad. We retrospectively enrolled eight patients (5 females) with Samter's triad who underwent at least one year of omalizumab therapy. Clinical data, functional parameters and questionnaires for asthma and nasal polyposis control were collected at baseline and follow-up.  We observed a significant reduction of moderate-to-severe asthma exacerbations, together with an increase of FEV1 and a reduction of steroids intake. An improvement in asthma control and nasal symptoms was also reported. This multicenter study confirms the effectiveness of omalizumab in patients affected by Samter's triad. Omalizumab may represent a potential therapeutic option for the management of this disease.

Intravenous immunoglobulin for the secondary prevention of stillbirth in obstetric antiphospholipid syndrome: A case series and systematic review of literature

OBJECTIVE

To evaluate the efficacy and safety of intravenous immunoglobulin (IVIg) in secondary prevention of pregnancy complications for patients with obstetric antiphospholipid syndrome (APS) and history of stillbirth.

METHODS

We described three cases of obstetric APS patients with history of stillbirth treated with IVIg in four pregnancies. In addition, we conducted a systematic literature review on the use of IVIg in obstetric APS with history of stillbirth.

RESULTS

Three patients with obstetric APS and history of stillbirth were treated with prophylactic IVIg, in addition to standard treatment (hydroxychloroquine, low-dose aspirin, low molecular weight heparin, and prednisone), in four pregnancies (three singleton and one twin). All pregnancies resulted in live healthy newborns. Long-term follow-up re-evaluations (24-53 months) did not shown any sign or symptom of active systemic disease, and the children were healthy. The systematic literature review retrieved only three cases of use of IVIg in obstetric APS patients with history of stillbirth. All three cases resulted in live healthy newborns. Only in one case, mild thrombocytopenia occurred during treatment, although this event was unlikely to be related to IVIg.

CONCLUSION

Our experience suggests that IVIg as secondary prevention of APS-related stillbirth is associated with good pregnancy and long-term outcomes, with no relevant safety concerns. However, the literature evidence on this topic is limited to few isolated cases, and further studies are needed to clarify which obstetric APS patients may benefit the most from IVIg.

Obstetric antiphospholipid syndrome is not associated with an increased risk of subclinical atherosclerosis

Objectives

The persistent positivity of aPLs, either isolated or associated with thrombotic and/or obstetric events (APS), has been associated with the increase of intima-media thickness (IMT) and carotid plaques. Despite the fact that aPLs can promote both thrombotic and obstetric complications, some pathogenic differences have been documented between the two entities. This study aimed to evaluate whether the atherosclerotic risk differs between subjects with obstetric and thrombotic APS.

Methods

A total of 167 APS women (36 obstetric and 131 thrombotic) were compared with 250 aPLs negative controls. IMT of the common carotid artery (CCA) and of the bulb and the prevalence of carotid plaques were assessed.

Results

CCA- and bulb-IMT were significantly higher in women with thrombotic APS, while being similar between the obstetric APS and the controls [CCA-IMT: mean (s.d.) 0.97 (0.49), 0.78 (0.22) and 0.81 (0.12) mm for the thrombotic, obstetric and control groups, respectively, P &lt; 0.001 between thrombotic and controls, P = 0.002 between thrombotic and obstetric; bulb-IMT: mean (s.d.) 1.38 (0.79), 0.96 (0.27) and 0.96 (0.51) mm for the thrombotic, obstetric and control groups, P &lt; 0.001]. Women with thrombotic APS had significantly increased risk of presenting carotid plaques. This risk was significantly lower in obstetric APS.

Conclusion

Unlike thrombotic APS, obstetric APS is not associated with an increase of markers of subclinical atherosclerosis. If confirmed on wider populations, these results could suggest different pathogenetic role of aPLs in promoting atherosclerosis in vascular and obstetric APS, and raise questions on the risk–benefit profile of thromboprophylaxis in obstetric APS outside pregnancy periods.

Long-term effectiveness and safety of secukinumab for treatment of refractory mucosal and articular Behçet's phenotype: a multicentre study

OBJECTIVE

To evaluate the effectiveness and safety of secukinumab in patients with a mucosal and articular Behçet's phenotype resistant to conventional and biologic treatment.

METHODS

A multicentre retrospective study was performed on 15 patients with a mucosal and articular phenotype of Behçet's syndrome fulfilling the International Criteria for Behçet's Disease and refractory to treatment with colchicine, disease-modifying antirheumatic drugs and at least one antitumour necrosis factor-α agent. Minimum follow-up was set at 6 months. Six patients with a polyarticular involvement were treated with secukinumab 300 mg/month, while all other cases received secukinumab 150 mg/month. Dose increase from 150 to 300 mg per month and shortening of administration frequency were allowed for poor disease control. Response evaluation was based on the number of oral ulcers in the previous 28 days and Disease Activity Score-28 for articular manifestations.

RESULTS

At 3 months of follow-up, nine (66.7%) patients achieved a response (complete or partial), and this proportion further increased to 86.7% at 6 months, 76.9% at 12 months, 90.0% at 18 months and 100.0% after 24 months. Notably, all patients who started with secukinumab 300 mg/month achieved complete response by month 6. Seven (46.7%) patients could achieve a response only after switching to a higher dosage.

CONCLUSIONS

Our study suggests that secukinumab at a dose of 150 and 300 mg per month is safe and effective for the long-term treatment of patients with Behçet's syndrome with a mucosal and articular phenotype refractory to previous treatments. Notably, secukinumab 300 mg/month resulted in superior complete mucosal and articular responses with no serious or dose-related adverse effects.

SARS-CoV-2 infection among patients with systemic autoimmune diseases

Objectives

This study aimed to evaluate the prevalence of clinically overt SARS-CoV-2 infection (COVID-19) among patients with systemic autoimmune diseases residing in Tuscany, and to compare it with that observed in the general Tuscan population.

Methods

In this cross-sectional study, Tuscan outpatients with systemic autoimmune diseases followed at a tertiary referral centre were telephonically interviewed between April 1st-14th 2020 to collect demographic and clinical data, information on ongoing immunomodulating/immunosuppressive treatments, and on the presence of symptoms suspected of SARS-CoV-2 or of a confirmed infection.

Results

458 patients were interviewed [74% female, median age 56 years (IQR 43–68)]; 56% of them were receiving corticosteroids, 44% traditional disease-modifying anti-rheumatic drugs (DMARDs), of whom 23% hydroxychloroquine, 5% colchicine, while 41% were on biologic DMARDs (of whom 9% on tocilizumab). Thirteen patients reported symptoms suggesting SARS-CoV-2 infection. Of them, 7 had undergone nasopharyngeal swab and only one was positive and developed severe SARS-CoV-2 complications. Within our cohort, the prevalence of SARS-CoV-2 infection was therefore 0.22% (0.01–1.21%), comparable to that observed in the general population of Tuscany [0.20% (0.20–0.21%), p = .597].

Conclusions

Patients with systemic autoimmune diseases do not seem to carry an increased risk of SARS- CoV-2 infection as compared to the general population.

•

Patients with systemic autoimmune diseases usually carry an increased risk of infections

•

Data on the occurrence of SARS-CoV-2 infection in these patients are scarce

•

We evaluated SARS-CoV-2 infection among 458 patients with systemic autoimmune diseases

•

The occurrence of the infection was similar to that observed in the general population

•

Patients with autoimmune diseases do not seem be at higher risk of SARS-CoV-2 infection

Adalimumab effectively controls both anterior and posterior noninfectious uveitis associated with systemic inflammatory diseases: focus on Behçet's syndrome

BACKGROUND

To compare the efficacy of Adalimumab (ADA) in noninfectious anterior uveitis (AU) and posterior segment (PS) involvement, associated with different conditions, with a focus on Behçet's syndrome (BS).

METHODS

In this retrospective, multicenter post-hoc study, we evaluated the efficacy of ADA in terms of ocular control and relapses in 96 patients with AU and PS uveitis, either idiopathic (IU) or associated with BS or with other systemic disorders (OSD) (Juvenile Idiopathic Arthritis, Psoriatic Arthritis, Ankylosing Spondylitis, Vogt-Koyanagi-Harada, Inflammatory Bowel Disease), followed in three tertiary referral centers.

RESULTS

Ninety-six patients (45 AU; 51 PS uveitis) were included. Eleven had IU, 58 BS, and 27 OSD. All patients with AU achieved complete long-term ocular control. In PS uveitis, 89%, 67% and 100% of patients with BS, IU and OSD achieved ocular control at the last follow-up (> 12 months), respectively. The lowest ocular relapse rate occurred in patients with AU with BS (1/13) or IU (0/2). ADA accounted for long-term disease control, and no predictors of ocular control and relapse were identified; particularly, ocular relapses seemed not related to systemic ones. Macular edema resolved in 75% and 67% of PS uveitis with BS and IU, respectively.

CONCLUSIONS

ADA controls both anterior and posterior uveitis, with an efficacy similar in IU, BS and OSD patients. In BS, the efficacy of ADA seems to be independent of demographic and clinical characteristics, and ocular relapses mostly occurred independently from systemic ones. Based on our results, ADA may represent a valid alternative in anterior refractory uveitis.

Comparison of Early vs. Delayed Anakinra Treatment in Patients With Adult Onset Still's Disease and Effect on Clinical and Laboratory Outcomes

Background: Aim of this study was to search for any difference in the outcome of patients with adult onset Still's disease (AOSD) treated with anakinra (ANK) in relation with the interval between disease onset and the start of anti-interleukin(IL)-1 treatment and according with the different lines of ANK treatment.

Patients and Methods: One hundred and forty-one AOSD patients treated with ANK have been retrospectively assessed. Statistically significant differences (p < 0.05) were analyzed in the frequency of ANK effectiveness, primary or secondary inefficacy to ANK and rate of resolution of clinical and laboratory AOSD manifestations after 3, 6, and 12 months since ANK treatment according with different lines of treatment and different times between AOSD onset and start of ANK.

Results: No significant differences were identified in the ANK effectiveness and frequency of primary or secondary inefficacy for patients starting ANK within 6 months (p = 0.19, p = 0.14, and p = 0.81, respectively) or 12 months (p = 0.37, p = 0.23, and p = 0.81, respectively) since AOSD onset compared with patients starting ANK thereafter; no significant differences were identified in ANK effectiveness and primary or secondary inefficacy according with different lines of ANK treatment (p = 0.06, p = 0.19, and p = 0.13, respectively). Patients starting ANK within 6 and 12 months since AOSD onset showed a significantly quicker decrease of erythrocyte sedimentation rate and C-reactive protein than observed among patients undergoing ANK treatment after 6 and 12 months. The number of swollen joints at the 3 month follow-up visit was significantly lower among patients undergoing ANK within 6 months since AOSD onset (p = 0.01), while no significance was identified at the 6 and 12 month assessments (p = 0.23 and p = 0.45, respectively). At the 3 and 6 month visits, the number of swollen joints was significantly higher among patients previously treated with conventional and biological disease modifying anti-rheumatic drugs (DMARDs) compared with those formerly treated only with conventional DMARDs (p < 0.017).

Conclusions: Clinical and therapeutic outcomes are substantially independent of how early ANK treatment is started in AOSD patients. However, a faster ANK effectiveness in controlling systemic inflammation and resolving articular manifestations may be observed in patients benefiting from IL-1 inhibition as soon as after disease onset.

Exercise with food withdrawal at thermoneutrality impacts fuel use, the microbiome, AMPK phosphorylation, muscle fibers, and thyroid hormone levels in rats

Exercise under fasting conditions induces a switch to lipid metabolism, eliciting beneficial metabolic effects. Knowledge of signaling responses underlying metabolic adjustments in such conditions may help to identify therapeutic strategies. Therefore, we studied the effect of mild exercise on rats submitted to food withdrawal at thermoneutrality (28°C) for 3 days. Animals were housed at thermoneutrality rather than the standard housing temperature (22°C) to avoid beta-adrenergic signaling responses that themselves affect metabolism and well-being. Quantitative analysis of multi-organ mRNA levels, myofibers, and serum metabolites shows that this protocol (a) boosts fat oxidation in muscle and liver, (b) reduces lipogenesis and increases gluconeogenesis in liver, (c) increases serum acylcarnitines (especially C4 OH) and ketone bodies and the use of the latter as fuel in muscle, (d) increases Type I myofibers, and (e) is associated with an increased thyroid hormone uptake and metabolism in muscle. In addition, stool microbiome DNA analysis revealed that food withdrawal dramatically alters the presence of bacterial genera associated with ketone metabolism. Taken together, this protocol induces a drastic switch toward increased lipid and ketone metabolism compared to exercise or food withdrawal alone, which may prove beneficial and may involve local thyroid hormones, which may be regarded as exercise mimetics.

Alveolar haemorrhage in ANCA-associated vasculitis: Long-term outcome and mortality predictors

INTRODUCTION

Alveolar haemorrhage (AH) is considered an important cause of morbidity and early mortality in anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitides (AAV).

OBJECTIVES

The aim of this study was to identify predictors of outcome in patients with AH-AAV and to evaluate outcome and causes of death in this subset.

MATERIALS AND METHODS

A multicenter retrospective study was conducted in 29 Italian Centers. Clinicians were asked to recruit all patients diagnosed with AAV-associated AH during the last 10 years, from 2007 to 2016. Univariate and multivariable analysis were performed.

RESULTS

One-hundred and six patients were included (median age at onset of 55 years [IQR 42-67]). The majority were ANCA-positive (PR3 57.1%, MPO 33.7%) and 72.6% had also renal involvement. At presentation, anaemia was shown in 97 (92.4%) patients, hemoptysis in 54 (51.9%), respiratory failure in 68 (66.7%), of whom 48 (70.6%), requiring respiratory support. At the end of the 37 months [IQR 13-77] follow-up, 19/106 (17.9%) patients were dead. The main causes of death were active disease and infections. By stepwise regression analysis, age >65 years (HR 3.66 [95% CI 1.4-9.51], p = 0.008) and the need for respiratory support (HR 4.58 [95% CI 1.51-13.87], p = 0.007) at AH onset were confirmed to be predictive of mortality.

CONCLUSIONS

Predictors of outcome in AAV-AH were determined. Factors related to the patient's performance status and the severity of the lung involvement strongly influenced the outcome. Balancing harms and benefits for the individual patient in induction and maintenance treatment strategies is crucial.

Stem-Cell-Derived Circulating Progenitors Dysfunction in Behçet's Syndrome Patients Correlates With Oxidative Stress

Behçet's syndrome (BS) is a systemic vasculitis considered as the prototype of a systemic inflammation-induced thrombotic condition whose pathogenesis cannot be explained just by coagulation abnormalities. Circulating hematopoietic progenitor cells (CPC), a population of rare, pre-differentiated adult stem cells originating in the bone marrow and capable of both self-renewal and multi-lineage differentiation, are mobilized in response to vascular injury and play a key role in tissue repair. In cardiovascular and thrombotic diseases, low circulating CPC number and reduced CPC function have been observed. Oxidative stress may be one of the relevant culprits that account for the dysfunctional and numerically reduced CPC in these conditions. However, the detailed mechanisms underlying CPC number reduction are unknown. On this background, the present study was designed to evaluate for the first time the possible relationship between CPC dysfunction and oxidative stress in BS patients. In BS patients, we found signs of plasma oxidative stress and significantly lower CD34+/CD45^−/dim and CD34+/CD45^−/dim/CD133+ CPC levels. Importantly, in all the considered CPC subsets, significantly higher ROS levels with respect to controls were observed. Higher levels of caspase-3 activity in all the considered CPC population and a strong reduction in GSH content in CPC subpopulation from BS patients with respect to controls were also observed. Interestingly, in BS patients, ROS significantly correlated with CPC number and CPC caspase-3 activity and CPC GSH content significantly correlated with CPC number, in all CPC subsets. Collectively, these data demonstrate for the first time that CPC from BS patients show signs of oxidative stress and apoptosis and that a reduced CPC number is present in BS patients with respect to controls. Interestingly, we observed an inverse correlation between circulating CPC number and CPC ROS production, suggesting a possible toxic ROS effect on CPC in BS patients. The significant correlations between ROS production/GSH content and caspase-3 activity point out that oxidative stress can represent a determinant in the onset of apoptosis in CPC. These data support the hypothesis that oxidative-stress-mediated CPC dysfunctioning may counteract their vascular repair actions, thereby contributing to the pathogenesis and the progression of vascular disease in BS.

Intravenous immunoglobulin therapy: a snapshot for the internist

Intravenous immunoglobulins are the cornerstone for the treatment of primary humoral immunodeficiencies and may be used for a great number of other autoimmune, neurological and hematological conditions as well. Given their wide application, the possibility of running across a patient who needs this kind of therapy is becoming increasingly common. Generally, intravenous immunoglobulins are well tolerated. However, numerous adverse reactions ranging from mild to severe have been reported and linked to patient- and product-related factors. For all these reasons, we present herein a comprehensive review of the on- and off-label applications of intravenous immunoglobulins and provide a guide for the internist how to minimize the risk of adverse reactions and manage them.

Vascular Behçet's syndrome: an update

Behçet's syndrome (BS) is a complex vasculitis, characterised by peculiar histological, pathogenetic and clinical features. Superficial venous thrombosis (SVT) and deep vein thrombosis (DVT) are the most frequent vascular involvements, affecting altogether 15-40% of BS patients. Atypical thrombosis is also an important clinical feature of BS, involving the vascular districts of the inferior and superior vena cava, suprahepatic veins with Budd-Chiari syndrome, portal vein, cerebral sinuses and right ventricle. On the other hand, arterial involvement, although affecting only 3-5% of patients, represents a unique feature of BS, with aneurysms potentially affecting peripheral, visceral and pulmonary arteries. Vascular events in BS are promoted by inflammation, with neutrophils playing a key role in the pathogenesis of thrombotic events; in turn, coagulative components such as fibrinogen, thrombin, factor Xa and factor VIIa amplify the inflammatory cascade. Understanding the contribution of inflammatory and coagulation components in the pathogenesis of BS vascular events is crucial to define the most effective therapeutic strategy. Control of vascular thrombosis is achieved with immunosuppressants drugs rather than anticoagulants. In particular, use of azathioprine and cyclosporine in association with low-dose corticosteroids should be considered in DVT and SVT cases, while treatment with cyclophosphamide together with anti-TNF-α agents can be effectively used in arterial involvement. More recently, the anti-TNF-α drugs have also been reported as a valid alternative for the treatment also of venous events, especially DVT. An exception to the use of anticoagulant in BS could be represented by cerebral veins thrombosis. In this review, we will depict the main characteristics of the vascular involvement in BS, briefly describing histological and pathogenetic features, while focusing on the clinical and therapeutical approaches of the vascular manifestations of BS.

Long-Term Retention Rate of Anakinra in Adult Onset Still's Disease and Predictive Factors for Treatment Response

Background: Anakinra (ANA) is an effective treatment choice in patients with adult onset Still’s disease (AOSD). Variables affecting treatment survival include loss of efficacy or adverse events, but also the decision to discontinue treatment after long-term clinical remission.

Objectives: Aims of this study were: (i) to assess the drug retention rate (DRR) of ANA during a long-term follow-up looking for any difference related to the line of biologic treatment, the concomitant use of conventional disease modifying anti-rheumatic drugs (cDMARDs) and the different type of AOSD (systemic versus chronic articular); (ii) to identify predictive factors of lack of efficacy, loss of efficacy, and ANA withdrawal owing to long-term remission.

Methods: AOSD patients classified according with Yamaguchi criteria and treated with ANA were retrospectively enrolled in 18 Italian tertiary Centers. Demographic, laboratory, clinical and therapeutic data related to the start of ANA (baseline), the 3-month assessment and the last follow-up visit while on ANA treatment were retrospectively collected and statistically analyzed.

Results: One hundred and forty-one AOSD patients (48 males, 93 females) treated with ANA for a mean period of 35.96 ± 36.05 months were enrolled. The overall DRR of ANA was 44.6 and 30.5% at the 60- and 120-month assessments, respectively, with no significant differences between: (i) biologic naïve patients and those previously treated with other biologics (log-rank p = 0.97); (ii) monotherapy and concomitant use of cDMARDs (log-rank p = 0.45); (iii) systemic and chronic articular types of AOSD (log-rank p = 0.67). No variables collected at baseline could predict primary inefficacy, while the number of swollen joints at baseline was significantly associated with secondary inefficacy (p = 0.01, OR = 1.194, C.I. 1.043–1.367). The typical AOSD skin rash was negatively related with ANA withdrawal owing to long-term remission (p = 0.03, OR = 0.224, C.I. 0.058–0.863).

Conclusion: Long-term DRR of ANA has been found excellent and is not affected by different lines of biologic treatment, concomitant use of cDMARDs, or type of AOSD. The risk of losing ANA efficacy increases along with the number of swollen joints at the start of therapy, while the typical skin rash is a negative predictor of ANA withdrawal related to sustained remission.

3,5 Diiodo-l-Thyronine (T₂) Promotes the Browning of White Adipose Tissue in High-Fat Diet-Induced Overweight Male Rats Housed at Thermoneutrality

The conversion of white adipose cells into beige adipose cells is known as browning, a process affecting energy metabolism. It has been shown that 3,5 diiodo-l-thyronine (T₂), an endogenous metabolite of thyroid hormones, stimulates energy expenditure and a reduction in fat mass. In light of the above, the purpose of this study was to test whether in an animal model of fat accumulation, T₂ has the potential to activate a browning process and to explore the underlying mechanism. Three groups of rats were used: (i) receiving a standard diet for 14 weeks; (ii) receiving a high-fat diet (HFD) for 14 weeks; and (iii) receiving a high fat diet for 10 weeks and being subsequently treated for four weeks with an HFD together with the administration of T₂. We showed that T₂ was able to induce a browning in the white adipose tissue of T₂-treated rats. We also showed that some miRNA (miR133a and miR196a) and MAP kinase 6 were involved in this process. These results indicate that, among others, the browning may be another cellular/molecular mechanism by which T₂ exerts its beneficial effects of contrast to overweight and of reduction of fat mass in rats subjected to HFD.

Interleukin-17/Interleukin-21 and Interferon-γ producing T cells specific for β2 Glycoprotein I in atherosclerosis inflammation of systemic lupus erythematosus patients with antiphospholipid syndrome

Systemic lupus erythematosus is frequently associated with antiphospholipid syndrome. Patients with lupus-antiphospholipid syndrome are characterized by recurrent arterial/venous thrombosis, miscarriages, and persistent presence of autoantibodies against phospholipid-binding proteins, such as β2-Glycoprotein I. We investigated the cytokine production induced by β2-Glycoprotein I in activated T cells that infiltrate in vivo atherosclerotic lesions of lupus-antiphospholipid syndrome patients. We examined the helper function of β2-Glycoprotein I-specific T cells for tissue factor production, as well as their cytolytic potential and their helper function for antibody production. Lupus-antiphospholipid syndrome patients harbor in vivo activated CD4⁺ T cells that recognize β2-Glycoprotein I in atherosclerotic lesions. β2-Glycoprotein I induces T-cell proliferation and expression of both Interleukin-17/Interleukin-21 and Interferon-γ in plaque-derived T-cell clones. β2-Glycoprotein I-specific T cells display strong help for monocyte tissue factor production, and promote antibody production in autologous B cells. Moreover, plaque-derived β2-Glycoprotein I-specific CD4⁺ T lymphocytes express both perforin-mediated and Fas/FasLigand-mediated-cytotoxicity. Altogether, our results indicate that β2-Glycoprotein I is able to elicit a local Interleukin-17/Interleukin-21 and Interferon-γ inflammation in lupus-antiphospholipid syndrome patients that might lead, if unabated, to plaque instability and subsequent arterial thrombosis, suggesting that the T helper 17/T helper 1 pathway may represent a novel target for the prevention and treatment of the disease.