Tofacitinib improved peripheral endothelial dysfunction and brain-derived neurotrophic factor levels in the rat adjuvant-induced arthritis model

Exploring candidate biomarkers for rheumatoid arthritis through cardiovascular and cardiometabolic serum proteome profiling

Introduction

RA patients are at higher risk of cardiovascular disease, influenced by therapies. Studying their cardiovascular and cardiometabolic proteome can unveil biomarkers and insights into related biological pathways.

Methods

This study included two cohorts of RA patients: newly diagnosed individuals (n=25) and those with established RA (disease duration >25 years, n=25). Both cohorts were age and sex-matched with a control group (n=25). Additionally, a longitudinal investigation was conducted on a cohort of 25 RA patients treated with methotrexate and another cohort of 25 RA patients treated with tofacitinib for 6 months. Clinical and analytical variables were recorded, and serum profiling of 184 proteins was performed using the Olink technology platform.

Results

RA patients exhibited elevated levels of 75 proteins that might be associated with cardiovascular disease. In addition, 24 proteins were increased in RA patients with established disease. Twenty proteins were commonly altered in both cohorts of RA patients. Among these, elevated levels of CTSL1, SORT1, SAA4, TNFRSF10A, ST6GAL1 and CCL18 discriminated RA patients and HDs with high specificity and sensitivity. Methotrexate treatment significantly reduced the levels of 13 proteins, while tofacitinib therapy modulated the expression of 10 proteins. These reductions were associated with a decrease in DAS28. Baseline levels of SAA4 and high levels of BNP were associated to the non-response to methotrexate. Changes in IL6 levels were specifically linked to the response to methotrexate. Regarding tofacitinib, differences in baseline levels of LOX1 and CNDP1 were noted between non-responder and responder RA patients. In addition, response to tofacitinib correlated with changes in SAA4 and TIMD4 levels.

Conclusion

In summary, this study pinpoints molecular changes linked to cardiovascular disease in RA and proposes candidate protein biomarkers for distinguishing RA patients from healthy individuals. It also highlights how methotrexate and tofacitinib impact these proteins, with distinct alterations corresponding to each drug's response, identifying potential candidates, as SAA4, for the response to these therapies.

Differential association of endothelial function with brain structure in youth with versus without bipolar disorder

BACKGROUND

Mood symptoms and disorders are associated with impaired endothelial function, a marker of early atherosclerosis. Given the increased vascular burden and neurostructural differences among individuals with mood disorders, we investigated the endothelial function and brain structure interface in relation to youth bipolar disorder (BD).

METHODS

This cross-sectional case-controlled study included 115 youth, ages 13-20 years (n = 66 BD; n = 49 controls [CG]). Cortical thickness and volume for regions of interest (ROI; insular cortex, ventrolateral prefrontal cortex [vlPFC], temporal lobe) were acquired from FreeSurfer processed T1-weighted MRI images. Endothelial function was assessed using pulse amplitude tonometry, yielding a reactive hyperemia index (RHI). ROI and vertex-wise analyses controlling for age, sex, obesity, and intracranial volume investigated for RHI-neurostructural associations, and RHI-by-diagnosis interactions.

RESULTS

In ROI analyses, higher RHI (i.e., better endothelial function) was associated with lower thickness in the insular cortex (β = -0.19, p_FDR = 0.03), vlPFC (β = -0.30, p_FDR = 0.003), and temporal lobe (β = -0.22, p_FDR = 0.01); and lower temporal lobe volume (β = -0.16, p_FDR = 0.01) in the overall sample. In vertex-wise analyses, higher RHI was associated with lower cortical thickness and volume in the insular cortex, prefrontal cortex (e.g., vlPFC), and temporal lobe. Additionally, higher RHI was associated with lower vlPFC and temporal lobe volume to a greater extent in youth with BD vs. CG.

CONCLUSIONS

Better endothelial function was associated with lower regional brain thickness and volume, contrasting the hypothesized associations. Additionally, we found evidence that this pattern was exaggerated in youth with BD. Future studies examining the direction of the observed associations and underlying mechanisms are warranted.

Cardiovascular risks associated with Janus kinase inhibitors: peering outside the black box

Considerable controversy related to the cardiovascular safety of Janus kinase inhibitors (JAKinibs) has arisen following the results of the ORAL Surveillance trial. In this trial of rheumatoid arthritis (RA) ≥ 50 years with at least one prevalent cardiovascular disease (CVD) risk factor, tofacitinib was not found to be non-inferior to tumour necrosis factor-alpha inhibitors (TNFi) with regards to the risk for major adverse cardiovascular events (MACE), venous thromboembolism (VTE) or malignancy. Following the results of ORAL Surveillance, the United States Food and Drug Administration (US FDA) issued a boxed warning regarding increased risks of MACE, VTE and malignancy with tofacitinib, baricitinib or upadacitinib in inflammatory arthritis or ulcerative colitis. Analysis of data from other trials (including long-term follow-up studies) of tofacitinib in RA, psoriasis, psoriatic arthritis, spondyloarthritis and inflammatory bowel diseases suggests an overall similar risk of MACE or VTE with tofacitinib when compared with TNFi. In specific patient populations with risk factors for or prior history of MACE or VTE, the risk of subsequent MACE or VTE with tofacitinib use is considerably heightened. Post-hoc analyses from ORAL Surveillance presented at the recent EULAR meeting further help to delineate patients with RA at increased risk of MACE/VTE with tofacitinib. Based on the available literature from trials and long-term follow-up studies of baricitinib and upadacitinib, there exists insufficient evidence to extend the warning of MACE/VTE with tofacitinib to these drugs. Ongoing post-marketing surveillance studies of JAKinibs in immune-mediated inflammatory diseases should help clarify CVD risk with JAKinibs.

Activation of spinal ephrin-B3/EphBs signaling induces hyperalgesia through a PLP-mediated mechanism

Ephrin B/EphB signaling pathway is involved in the regulation of pain caused by spinal cord injury. However, the role of ephrin-B3/EphBs signaling in regulation of nociceptive information is poorly understood. In the present study, formalin-induced inflammatory pain, mechanical allodynia and thermal hyperalgesia, was measured using Efnb3 mutant mice (Efnb3^-/- ) and wild-type (Efnb3^+/+ ) mice. The spinal cord (L4-6) was selected for molecular and cellular identification by western blotting and immunofluorescence. Efnb3 mutant mice showed a significant increased the thermal and mechanical threshold, followed by aberrant thin myelin sheath. Furthermore, expression of proteolipid protein (PLP) was significantly lower in L4-6 spinal cord of Efnb3^-/- mice. These morphological and behavioral abnormalities in mutant mice were rescued by conditional knock-in of wild-type ephrin-B3. Intrathecal administration of specific PLP siRNA significantly increased the thermal and mechanical threshold hyperalgesia in wild-type mice. However, overexpressing PLP protein by AAV9-PLP could decrease the sensitivity of mice to thermal and mechanical stimuli in Efnb3^-/- mice, compared with scrabble Efnb3^-/- mice. Further, Efnb3^lacz mice, which have activities to initiate forward signaling, but transduce reverse signals by ephrin-B3, shows normal acute pain behavior, compared with wild type mice. These findings indicate that a key molecule Efnb3 act as a prominent contributor to hyperalgesia and essential roles of ephrin-B3/EphBs in nociception through a myelin-mediated mechanism.