Treating rheumatoid arthritis

Fengshi Liuhe Decoction treatment for rheumatoid arthritis via the Fzd6/NF-κB signaling axis

To explore whether Fengshi Liuhe Decoction (FLD) alleviates rheumatoid arthritis (RA) via the Fzd6/NF-κB signaling axis. We used real-time quantitative PCR (qPCR) and western blotting (WB) to determine the genes of the frizzled (Fzd) protein 1- Fzd protein 10 that are significantly differentially expressed between normal rat fibroblast-like synoviocyte (FLS) and collagen II-induced arthritis (CIA) rat FLS. Next, we used enzyme-linked immunosorbent assay (ELISA) to evaluate the levels of inflammatory factors in cell culture supernatant to determine the ability of FLD to ameliorate RA. Finally, we employed WB to detect the key gene expression in protein levels of the Fzd6/NF-κB signaling axis among normal rat FLS, CIA rat FLS, and FLD-treated CIA rat FLS. Our results showed that Fzd6 expression was significantly higher in CIA rat FLS at both the mRNA and protein levels than in normal rat FLS. FLD was found to downregulate Fzd6 and inflammatory factors, including COX-2, IL-8, and TNF-α, at both the mRNA and protein levels. FLD was also found to downregulate the total protein levels of Fzd6 and the NF-κB signaling pathway key gene phosphorylation of p-p65/p65 and p-IκBα/IκBα. Moreover, FLD inhibited the nuclear translocation of NF-κB p65 in CIA rat FLS. FLD can alleviate inflammation of CIA rat FLS via the Fzd6/NF-κB signaling axis.

PTEN: an emerging target in rheumatoid arthritis?

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a critical tumor suppressor protein that regulates various biological processes such as cell proliferation, apoptosis, and inflammatory responses by controlling the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PI3K/AKT) signaling pathway. PTEN plays a crucial role in the pathogenesis of rheumatoid arthritis (RA). Loss of PTEN may contribute to survival, proliferation, and pro-inflammatory cytokine release of fibroblast-like synoviocytes (FLS). Also, persistent PI3K signaling increases myeloid cells' osteoclastic potential, enhancing localized bone destruction. Recent studies have shown that the expression of PTEN protein in the synovial lining of RA patients with aggressive FLS is minimal. Experimental upregulation of PTEN protein expression could reduce the damage caused by RA. Nonetheless, a complete comprehension of aberrant PTEN drives RA progression and its interactions with other crucial molecules remains elusive. This review is dedicated to promoting a thorough understanding of the signaling mechanisms of aberrant PTEN in RA and aims to furnish pertinent theoretical support for forthcoming endeavors in both basic and clinical research within this domain.

Prevalence and Comorbidities Among Individuals With Rheumatoid Arthritis in the Saudi Arabian Context

BACKGROUND

 Rheumatoid arthritis (RA) in Saudi Arabia (SA) is a significant health concern with a notable impact on individuals and the healthcare system. This study aimed to investigate the prevalence and profile of comorbidities in patients with RA.

METHODOLOGY

 This is a retrospective descriptive study involving 150 RA patients from August 2022 to August 2023, which was conducted at Khamis Mushait General Hospital, a major healthcare institution in SA. We examined the medical records to gather pertinent information. Stata Statistical Software: Release 18 (2023; StataCorp LLC, College Station, Texas, United States) was used for data analysis. The examination focused on sociodemographic factors, disease duration, prescribed medications (including methotrexate and biologic therapy), and the presence of comorbidities. Approval for the study was obtained from the Institutional Review Board of the Aseer Ministry of Health (approval number: H-06-B-091).

RESULTS

 The study found a high prevalence of comorbidities in patients with RA. Around 96.7% of the patients had at least one documented comorbidity, highlighting this population's burden of additional health conditions. The most common comorbidity observed was anemia, affecting 48.7% of the patients. Other frequently observed comorbidities include hypertension, hyperlipidemia, diabetes mellitus, osteoporosis, interstitial lung disease, chronic renal disease, stroke, and coronary artery disease. The factors influencing comorbidities included an odds ratio of 1.086 (p=0.025), while being male was associated with lower odds (odds ratio=0.529, p=0.017). Additionally, disease duration (odds ratio=1.164, p=0.007), methotrexate use (odds ratio=2.553, p=0.001), and receiving biologic therapy (odds ratio=3.488, p<0.001) were significant contributors to comorbidities.

CONCLUSION

 These findings highlight the need for comprehensive approaches to address RA and its associated comorbidities. Research and awareness initiatives are essential to understand better the specific nuances of RA in SA, leading to improved diagnostic and treatment strategies for the needs of the local population.

Plasma Cholinesterase Activity in Patients With Rheumatoid Arthritis and Toxoplasmosis

Background and objective Rheumatoid arthritis (RA) is a chronic autoimmune disease causing synovium inflammation and functional impairment. Toxoplasmosis is an intracellular zoonotic parasitic infection and a risk factor in immunosuppressed diseases including RA. The involvement of the cholinergic mechanism is not clear when both diseases exist in combination. This study aimed to examine plasma cholinesterase (ChE) activity in patients suffering from RA with concomitant toxoplasmosis, taking into account the enzyme susceptibility to in vitro inhibitory challenge with the organophosphate dichlorvos in RA patients. Methods This was a case-control study involving 88 RA patients and 61 healthy controls of both genders. The RA patients were allocated into three groups. The first group received no therapy (n=14), the second group received conventional anti-arthritis therapy (n=49), and the third group received conventional + biologic therapy (n=25). Plasma ChE activity was determined by an electrometric method. Plasma samples were screened for Toxoplasma gondii (T. gondii) infection, using ELISA T. gondii antibodies IgG and IgM. In vitro inhibition of plasma ChE activity was assessed by incubating the samples with dichlorvos at 0.25 and 0.5 μM. The time-dependent dichlorvos (0.25 μM)-induced plasma ChE inhibition and its kinetics were determined. Results The RA patients comprised 76 (86.4%) females and 12 males (13.6%), whereas healthy controls included 22 (36.1%) females and 39 (63.9%) males. The rates of toxoplasmosis IgG positivity in controls and RA patients were 26.2% and 39.8%, respectively. Plasma ChE activity in patients with RA was significantly higher than that in the control group, by 16%. Plasma ChE values of RA patients with conventional therapy and conventional + biologic therapy were higher than that of the control group, by 18% and 27%, respectively. Odds and risk ratios of elevated plasma ChE activity (20%) in RA patients with therapy indicated that high plasma ChE activity among RA patients with therapy is a risk factor. The plasma ChE activity of T. gondii IgG-positive RA patients was not significantly different from that of the IgG-negative ones. Dichlorvos at 0.25 and 0.5 μM significantly inhibited in vitro plasma ChE activity in controls and RA patients. The rates of plasma ChE inhibition by dichlorvos were lower in the RA groups with conventional therapy in comparison with those in the control group (77% vs. 91%). Examining the dichlorvos time-dependent ChE inhibition kinetics, RA groups showed increases in the half-life of inhibition by 23.6% to 32.7% and the total inhibition time by 23.5% to 32.5%, together with decreases in the inhibition rate constant by 19% to 24.5%, an indication of reduced inhibition rate of plasma ChE activity compared to that of the control group. Conclusions The autoimmune nature of RA and its chronicity might have contributed to the increase in plasma ChE activity among the patients. This increase in enzyme activity could be a risk factor in RA patients undergoing conventional therapy alone or in combination with biologic therapy; however, the clinical significance of such a condition remains obscure at present. The in vitro inhibition of plasma ChE activity in RA patients suggests reduced susceptibility of the enzyme to ChE inhibition by dichlorvos. Toxoplasmosis was not a risk factor when plasma ChE activity was taken into account among RA patients.