Rheumatoid arthritis and Cognitive decline

Neutrophil extracellular traps: Potential targets for the treatment of rheumatoid arthritis with traditional Chinese medicine and natural products

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. Abnormal formation of neutrophil extracellular traps (NETs) at the synovial membrane leads to the release of many inflammatory cytokines, including IL-1β, IL-6, and TNF-α. Elastase, histone H3, and myeloperoxidase, which are carried by NETs, damage the soft tissues of the joints and aggravate the progression of RA. The balance of NET formation coordinates the pro-inflammatory and anti-inflammatory effects and plays a key role in the development of RA. Therefore, when NETs are used as effector targets, highly targeted drugs with fewer side effects can be developed to treat RA without damaging the host immune system. Currently, an increasing number of studies have shown that traditional Chinese medicines and natural products can regulate the formation of NETs through multiple pathways to counteract RA, which shows great potential for the treatment of RA and has a promising future for clinical application. In this article, we review the latest biological progress in understanding NET formation, the mechanism of NETs in RA, and the potential targets or pathways related to the modulation of NET formation by Chinese medicines and natural products. This review provides a relevant basis for the use of Chinese medicines and natural products as natural adjuvants in the treatment of RA.

Investigating Modifiable Risk Factors Across Dementia Subtypes: Insights from the UK Biobank

This study investigates the relationship between modifiable risk factors and dementia subtypes using data from 460,799 participants in the UK Biobank. Utilizing univariate Cox proportional hazards regression models, we examined the associations between 83 modifiable risk factors and the risks of all-cause dementia (ACD), Alzheimer's disease (AD), and vascular dementia (VD). Composite scores for different domains were generated by aggregating risk factors associated with ACD, AD, and VD, respectively, and their joint associations were assessed in multivariable Cox models. Additionally, population attributable fractions (PAF) were utilized to estimate the potential impact of eliminating adverse characteristics of the risk domains. Our findings revealed that an unfavorable medical history significantly increased the risk of ACD, AD, and VD (hazard ratios (HR) = 1.88, 95% confidence interval (95% CI): 1.74-2.03, p < 0.001; HR = 1.80, 95% CI: 1.54-2.10, p < 0.001; HR = 2.39, 95% CI: 2.10-2.71, p < 0.001, respectively). Blood markers (PAF = 12.1%; 17.4%) emerged as the most important risk domain for preventing ACD and VD, while psychiatric factors (PAF = 18.3%) were the most important for preventing AD. This study underscores the potential for preventing dementia and its subtypes through targeted interventions for modifiable risk factors. The distinct insights provided by HR and PAF emphasize the importance of considering both the strength of the associations and the population-level impact of dementia prevention strategies. Our research provides valuable guidance for developing effective public health interventions aimed at reducing the burden of dementia, representing a significant advancement in the field.

Abelmoschus manihot (L.) medik. seeds alleviate rheumatoid arthritis by modulating JAK2/STAT3 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Abelmoschus manihot (L.) Medik. Seeds (AMS, སོ་མ་ར་ཛ།), a Tibetan classical herbal in China, are rich in flavonoids and phenolic glycosides compounds, such as quercetin and its derivatives. Moreover, it has been found to possess anti-rheumatoid arthritis (RA) effects. Nonetheless, its anti-RA mechanism is yet unknown.

AIM OF THE STUDY

This research aimed to examine the active ingredients of AMS as well as potential pharmacological mechanisms in AMS on RA.

MATERIALS AND METHODS

The ultra-performance liquid chromatography-electrospray ionization-tandem multistage mass spectrometry (UPLC-ESI-IT-MSn) technique was used to determine the primary chemical components of AMS that were responsible for the therapeutic effects on RA. In addition, 36 male Wistar rats weighing between 200 and 220 g were classified at random into six groups [normal control group, collagen-induced arthritis (CIA) group, methotrexate group (positive control, 1.05 mg/kg), AMS group (157.5 mg/kg, 315 mg/kg, 630 mg/kg)]. CIA rats were given AMS extract by intragastric administration for 28 days, and their ankles were photographed to observe the degree of swelling. Further, the arthritis score, paws swelling, and body weight changes of CIA rats were determined to observe whether AMS has any effect on RA, and synovial and cartilage tissue injuries were identified by histopathology. Besides, the levels of IL-10, TNF-α, IL-1β, INF-γ, etc. in serum were estimated by ELISA. Western blot experiments were implemented to identify the expression levels of protein involved in the JAK2/STAT3 signaling pathway in the CIA rats' synovial tissues. Moreover, the mechanisms and targets of active ingredient therapy of AMS for RA were predicted using network pharmacology and then verified using molecular docking.

RESULT

In the present study, 12 compounds were detected by UPLC-ESI-IT-MSn, such as quercetin and its derivative which could be potential active ingredients that contribute to the anti-RA properties of AMS. Our in vivo studies on CIA rats revealed that an AMS-H dose of 630 mg/kg significantly improved joint damage while decreasing the arthritic index and paw swelling. Furthermore, AMS inhibited the INF-γ, IL-6, IL-17, IL-1β, and TNF-α, levels while upregulating the expression of anti-inflammatory cytokines IL-10 and IL-4 in serum. Besides, AMS inhibited the protein Bcl-2/Bax, STAT3, and JAK2 levels, and promoted the expression of Caspase3, SOCS1, and SOCS3 in the JAK2/STAT3 pathway. Additionally, the JAK/STAT signaling pathway was found to perform a remarkable function in the AMS therapy of RA as evidenced by enrichment in GO terms and KEGG pathways. Meanwhile, data from molecular docking experiments indicated that the core targets of PIK3CA, JAK2, and SRC bound stably to the active ingredients of mimuone, 4'-methoxy-bavachromanol, and quercetin.

CONCLUSION

According to these findings, the AMS could improve joint inflammation in CIA rats, and its underlying mechanism could be linked to the regulation of the JAK2/STAT3 pathway. Therefore, AMS might become a promising agent for alleviating inflammation in RA patients.

Functional dysconnectivity and microstructural impairment of the cortico-thalamo-cortical network in women with rheumatoid arthritis: A multimodal MRI study

Background

Cognitive deficits are common in rheumatoid arthritis (RA) patients, but the mechanisms remain unclear. We investigated the effective connectivity and structural alterations of the core brain regions in RA patients with cognitive impairment.

Methods

Twenty-four female patients with RA and twenty-four healthy controls were enrolled. We analyzed abnormal brain activity patterns using functional MRI during the Iowa gambling task (IGT) and core regions effective connectivity using dynamic causal model (DCM). Structural alterations of white matter volume (WMV) and gray matter volume (GMV) were detected using voxel-based morphometry (VBM).

Results

RA patients showed altered activation patterns of the cortico-thalamo-cortical network, increased coupling strength from the left ventromedial prefrontal gyrus to the anterior cingulate cortex (ACC), the ACC to the right thalamus, and decreased connectivity from the thalamus to left hippocampus. VBM structural analysis showed increased GMV in the bilateral orbital frontal gyrus, bilateral hippocampus and right putamen, and reduced GMV and WMV in the bilateral thalamus in RA patients. Right thalamic GMV and WMV were positively correlated with the right thalamus-to-hippocampus connective strength. Additionally, the bold signal, GMV and WMV of the right thalamus were positively correlated with cognitive performance (IGT score) in RA patients.

Conclusion

Results suggest a structural and functional deficiency in the cortico-thalamo-cortical network, which is characterized by increased ACC-to-thalamus strength and reduced thalamus-to-hippocampus coupling in RA patients. The cognitive dysfunction may be the result of compensatory measures against imbalanced cortico-thalamic-cortical coupling.

Anxiety and depression in rheumatoid arthritis patients: prevalence, risk factors and consistency between the Hospital Anxiety and Depression Scale and Zung's Self-rating Anxiety Scale/Depression Scale

Objectives

The aim was to explore the prevalence and independent risk factors for anxiety and depression in RA patients and to assess the consistency between the hospital anxiety and depression scale (HADS) and Zung's self-rating anxiety scale/depression scale (SAS/SDS).

Methods

In total, 160 RA patients and 60 healthy controls (HCs) were enrolled consecutively, and HADS and SAS/SDS were completed.

Results

The HADS-defined anxiety rate, HADS-defined depression rate, SAS-defined anxiety rate and SDS-defined depression rate were 36.9, 36.3, 29.4 and 29.4%, respectively, in RA patients, all of which were much higher in RA patients than in HCs (all P < 0.001). A relatively high consistency was observed between HADS-defined anxiety and SAS-defined anxiety (κ = 0.551, P < 0.001) and between HADS-defined depression and SDS-defined depression (κ = 0.563, P < 0.001) in RA patients. Interestingly, screened by multivariate logistic regression analyses, single/divorced/widowed marital status, swollen joint count, disease duration, ESR, physician's global assessment (PhGA) and DAS28 were independently correlated with HADS-defined or SAS-defined anxiety risk in RA patients; meanwhile, female biological sex, single/divorced/widowed marital status, rural location, disease duration, PhGA and DAS28 were independently associated with HADS-defined or SDS-defined depression risk in RA patients.

Conclusion

Anxiety and depression are highly prevalent in RA patients and are independently correlated with single/divorced/widowed marital status and higher disease activity. In addition, the HADS presents a high consistency with the SAS/SDS with many fewer questions, which might be more suitable for long-term assessment of RA.

Nitric Oxide Synthases in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by severe joint damage and disability. However, the specific mechanism of RA has not been thoroughly clarified over the past decade. Nitric oxide (NO), a kind of gas messenger molecule with many molecular targets, is demonstrated to have significant roles in histopathology and homeostasis. Three nitric oxide synthases (NOS) are related to producing NO and regulating the generation of NO. Based on the latest studies, NOS/NO signaling pathways play a key role in the pathogenesis of RA. Overproduction of NO can induce the generation and release of inflammatory cytokines and act as free radical gas to accumulate and trigger oxidative stress, which can involve in the pathogenesis of RA. Therefore, targeting NOS and its upstream and downstream signaling pathways may be an effective approach to managing RA. This review clearly summarizes the NOS/NO signaling pathway, the pathological changes of RA, the involvement of NOS/NO in RA pathogenesis and the conventional and novel drugs based on NOS/NO signaling pathways that are still in clinical trials and have good therapeutic potential in recent years, with an aim to provide a theoretical basis for further exploration of the role of NOS/NO in the pathogenesis, prevention and treatment of RA.

Nutrition Patterns and Their Gender Differences among Rheumatoid Arthritis Patients: A Descriptive Study

Dietary factors probably play a role in the pathogenesis and clinical course of rheumatoid arthritis (RA). There is a paucity of specific dietary guidelines for RA patients and little information on their implementation in daily life. Therefore, this study aimed to determine the nutritional status and provision of nutritional education among outpatients with RA. Here, 61 patients were included with a sex ratio of 2.03 (f/m). Based on BMI, 22% of women were overweight and 32% obese, whereas 50% of men were overweight and 30% obese. Fasting blood and a 3-day estimated dietary record were collected. Additionally, patients were asked whether they had already received information about a specific diet as part of their disease treatment plan. Elevated total cholesterol levels were found in 76% of women and in 60% of men caused by increased non-HDL-C levels. The dietary intake assessment showed a lower self-reported intake of energy, polyunsaturated fat, carbohydrates, fiber, and several micronutrients than recommended. Regarding healthy eating, all patients reported familiarity with dietary recommendations, but found it difficult to implement the recommendations into their diets. These findings suggested that RA patients need more specific recommendations and education in clinical practice to improve the quality of their diet.

Advancement in understanding the role of ferroptosis in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic, systemic disease of unknown etiology. The primary manifestation of RA is inflammatory synovitis, which eventually leads to deformity and functional loss. Ferroptosis is a non-apoptosis form of cell death that depends on intracellular iron accumulation. This leads to an increase in reactive oxygen species (ROS) induced-lipid peroxidation. The underlying mechanisms of ferroptosis are System Xc- and Glutathione metabolism, regulation of glutathione peroxidase 4 activity, and ROS generation. Recent studies have shown an association between the pathogenesis of RA and ferroptosis, suggesting the involvement of ferroptosis in the onset and progression of RA. In this review, we have focused on the mechanism of ferroptosis and its association with RA pathogenesis. Further, we discuss the status of therapeutics targeting ferroptosis in the treatment of patients with RA. Targeting ferroptosis could be a potential therapeutic approach for RA treatment.