Tofacitinib Decreases Autophagy of Fibroblast-Like Synoviocytes From Rheumatoid Arthritis Patients

DeepDrug as an expert guided and AI driven drug repurposing methodology for selecting the lead combination of drugs for Alzheimer's disease

Alzheimer's Disease (AD) significantly aggravates human dignity and quality of life. While newly approved amyloid immunotherapy has been reported, effective AD drugs remain to be identified. Here, we propose a novel AI-driven drug-repurposing method, DeepDrug, to identify a lead combination of approved drugs to treat AD patients. DeepDrug advances drug-repurposing methodology in four aspects. Firstly, it incorporates expert knowledge to extend candidate targets to include long genes, immunological and aging pathways, and somatic mutation markers that are associated with AD. Secondly, it incorporates a signed directed heterogeneous biomedical graph encompassing a rich set of nodes and edges, and node/edge weighting to capture crucial pathways associated with AD. Thirdly, it encodes the weighted biomedical graph through a Graph Neural Network into a new embedding space to capture the granular relationships across different nodes. Fourthly, it systematically selects the high-order drug combinations via diminishing return-based thresholds. A five-drug lead combination, consisting of Tofacitinib, Niraparib, Baricitinib, Empagliflozin, and Doxercalciferol, has been selected from the top drug candidates based on DeepDrug scores to achieve the maximum synergistic effect. These five drugs target neuroinflammation, mitochondrial dysfunction, and glucose metabolism, which are all related to AD pathology. DeepDrug offers a novel AI-and-big-data, expert-guided mechanism for new drug combination discovery and drug-repurposing across AD and other neuro-degenerative diseases, with immediate clinical applications.

3-MA attenuates collagen-induced arthritis in vivo via anti-inflammatory effect and autophagy inhibition

BACKGROUND

Rheumatoid arthritis (RA) is a chronic autoimmune disease which afflicts about nearly 1% of global population. RA results in synovitis and cartilage/bone damage, even disability which aggravates the health burden. Many drugs are used to relieve RA, such as glucocorticoids (GCs), non-steroidal anti-inflammatory drugs (NSAIDs), and disease-modifying anti-rheumatic drugs (DMARDs) in the clinical treatment. However, present clinical drugs have various disadvantages such as poor bioavailability and short biological half-life and drug resistance, or adverse effects. A recent study showed autophagy modulation may be a novel strategy in the treatment of RA. 3-Methylademine (3-MA), is the most widely used autophagy inhibitor, which blocks autophagy at the initiation and maturation stages. The aim of this study is to evaluate the effect of 3-MA in collagen-induced-arthritis (CIA) mice and further elucidate how 3-MA attenuated inflammation, and cartilage/bone damage in arthritis.

METHODS

An in-vivo mouse collagen-induced arthritis model was applied to compare differences in ankle destruction among control mice and CIA mice treated with or without 3-MA. Bone and cartilage destruction degree was evaluated by histology and micro-computed tomography (µCT). Further in-vivo assays utilized mouse serum samples to investigate inflammatory levels, oxidative levels, and bone resorption cytokines. At last, an immunofluorescence assay was applied to detect the autophagy level among the three groups.

RESULTS

The in-vivo mouse collagen-induced arthritis model showed that CIA mice revealed apparent hind paw and ankle swelling which was aggravated gradually along with time, while 3-MA treatment attenuated swelling gradually. µCT and histological results showed typical lesions in CIA group while 3-MA treatment alleviated arthritis-related destruction. Serum assay showed that 3-MA significantly reduced inflammatory cytokines levels, suppressed oxidative levels and bone resorption cytokines. Immunofluorescence assay revealed 3-MA significantly inhibited the abnormal autophagy level in CIA mouse ankle.

CONCLUSIONS

3-MA protects bone destruction in CIA-induced mice arthritis by anti-inflammatory effect and autophagy inhibition.

Silencing aquaporin 1 inhibits autophagy to exert anti-rheumatoid arthritis effects in TNF-α-induced fibroblast-like synoviocytes and adjuvant-induced arthritis rats : Names of authors

OBJECTIVE

Fibroblast-like synoviocytes (FLS) are key players in rheumatoid arthritis (RA) by resisting apoptosis via increased autophagy. Elevated synovial aquaporin 1 (AQP1) affects RA FLS behaviors, but its relationship with FLS autophagy is unclear. We aim to clarify that silencing AQP1 inhibits autophagy to exert its anti-RA effects.

METHODS

We studied the effects and mechanisms of AQP1 silencing on autophagy in TNF-α-induced RA FLS and examined the crucial role of autophagy inhibition in its impacts on RA FLS pathogenic behaviors. We explored whether silencing synovial AQP1 relieved rat adjuvant-induced arthritis (AIA) by reducing synovial autophagy.

RESULTS

TNF-α stimulation increased AQP1 expression and autophagy levels in RA FLS, with a positive correlation between them. AQP1 silencing inhibited autophagy in TNF-α-stimulated RA FLS, along with suppressing proliferation, promoting apoptosis, and mitigating inflammation. Notably, the inhibitory effects of AQP1 silencing on RA FLS pathogenic behaviors were cancelled by autophagy activation with rapamycin (Rapa) but enhanced by autophagy inhibition using 3-Methyladenine. Mechanistically, silencing AQP1 enhanced the binding of Bcl-2 to Beclin1 by decreasing Beclin1-K63 ubiquitination, thus inhibiting RA FLS autophagy. In vivo, silencing synovial AQP1 relieved the severity and development of rat AIA, alongside reducing Ki67 expression, promoting apoptosis, and decreasing autophagy within AIA rat synovium. Expectedly, the Rapa co-administration nullified the anti-AIA effects of silencing synovial AQP1.

CONCLUSION

These findings reveal that silencing AQP1 inhibits RA FLS pathogenic behaviors and attenuates rat AIA through autophagy inhibition. This study may help clarify the pathogenic role of AQP1 in enhancing autophagy during RA development.

JAK Inhibitors in Rheumatoid Arthritis: Immunomodulatory Properties and Clinical Efficacy

Rheumatoid arthritis (RA) is a highly prevalent autoimmune disorder. The pathogenesis of the disease is complex and involves various cellular populations, including fibroblast-like synoviocytes, macrophages, and T cells, among others. Identification of signalling pathways and molecules that actively contribute to the development of the disease is crucial to understanding the mechanisms involved in the chronic inflammatory environment present in affected joints. Recent studies have demonstrated that the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway regulates the behaviour of immune cells and contributes to the progression of RA. Several JAK inhibitors, such as tofacitinib, baricitinib, upadacitinib, and filgocitinib, have been developed, and their efficacy and safety in patients with RA have been comprehensively investigated in a number of clinical trials. Consequently, JAK inhibitors have been approved and registered as a treatment for patients with RA. In this review, we discuss the involvement of JAK/STAT signalling in the pathogenesis of RA and summarise the potential beneficial effects of JAK inhibitors in cells implicated in the pathogenesis of the disease. Moreover, we present the most important phase 3 clinical trials that evaluated the use of these agents in patients.

PTEN-mediated FOXO signaling affects autophagy, migration and invasion of rheumatoid arthritis fibroblast-like synoviocytes

Rheumatoid arthritis (RA) is a chronic, progressive, systemic autoimmune disease. Among them, abnormal proliferation, migration and vascularization of fibroblast-like synoviocytes (FLS) are the main pathological basis of persistent synovitis and bone destruction in RA. In the current study, we attempted to find effective molecular mechanisms for the treatment of RA by investigating RA-FLS. Firstly, the study was conducted to identify the potential target gene PTEN and its related signaling pathway through bioinformatics analysis. Subsequently, the target gene PTEN overexpression was regulated by cell transfection. The expression of FOXO signaling factors and autophagy-related proteins were detected by western blotting assay. Cell proliferation was measured by CCK-8 and EdU assays. Inflammation level was detected by ELISA. Cell migration and invasion were detected using wound healing assay and transwell chamber assay, respectively. Cell apoptosis was detected using flow cytometry. The results showed that overexpression of PTEN activated FOXO1 signaling in RA-FLS, and regulated autophagy, proliferation, invasion, migration, and the levels of pro-inflammatory factors in the disease. In conclusion, PTEN might provide an effective therapeutic strategy for rheumatoid arthritis by mediating the FOXO1 signaling pathway.

Tofacitinib restores psoriatic arthritis fibroblast-like synoviocytes function via autophagy and mitochondrial quality control modulation

OBJECTIVES

To evaluate the in vitro effect of tofacitinib on autophagy activity of psoriatic arthritis (PsA) fibroblast-like synoviocytes (FLS), and to confirm its activity on inflammatory and invasive properties of FLS and synovial cells, deepening the impact on mitochondrial function.

METHODS

FLS, peripheral blood mononuclear cells (PBMCs), and synovial cells from active PsA patients were cultured with tofacitinib 1 μM or vehicle control for 24 h. Autophagy was measured by Western blot and by fluorescence microscopy. Chemokines/cytokines released into culture supernatants were quantified by ELISA, while invasive properties of FLS by migration assays. Specific mitochondrial probes were adopted to measure intracellular reactive oxygen species (ROS), mitochondrial potential, morphology, turnover and mitophagy. Oxygen consumption rate (OCR), reflecting oxidative phosphorylation, was quantified using the Seahorse technology. Differences were determined by adopting the non-parametric Wilcoxon signed rank test.

RESULTS

18 patients with moderately-to-severely active PsA were enrolled. Tofacitinib significantly increased the levels of the autophagy markers LC3-II and ATG7 in PsA FLS compared to vehicle control, suggesting an increase in spontaneous autophagy activity; no effect was highlighted in PBMCs and synovial cells cultures. Tofacitinib reduced migration properties of PsA FLS, and reduced MCP-1 and IL-6 release into FLS and synovial cells cultures supernatants. Furthermore, tofacitinib decreased intracellular ROS production, increased basal OCR, ATP production and maximal respiratory capacity, and enhanced mitophagy and mitochondrial turnover.

CONCLUSIONS

The JAK inhibitor tofacitinib reduces the pro-invasive and pro-inflammatory properties of PsA FLS. Autophagy induction and mitochondrial quality control modulation by tofacitinib might contribute to FLS function restoration.

A novel drug combination of Tofacitinib and Iguratimod alleviates rheumatoid arthritis and secondary osteoporosis

BACKGROUND

The inadequate response of some patients with rheumatoid arthritis (RA) to current therapies is an issue that needs to be addressed. Patients with refractory RA (RRA) are often accompanied by high Tumor necrosis factor (TNF) expression. We evaluated the synergistic therapeutic effects of the combination of Iguratimod (IGU) and Tofacitinib (TOF) on RRA and secondary osteoporosis.

METHODS

Pathological changes in the ankle joints of collagen-induced arthritis (CIA) + TNF model rats were assessed using hematoxylin and eosin (HE) staining. Immunohistochemistry (IHC) and immunofluorescence (IF) were used to evaluate pyroptosis-related protein levels in the synovial tissues. Moreover, the knee joint was investigated by performing HE staining, IHC, and micro-computed tomography. Furthermore, in vitro, western blotting and enzyme-linked immunosorbent assay (ELISA) were performed to detect the effects of TOF and IGU on TNF-α-induced pyroptosis in fibroblast-like synoviocytes of RA.

RESULTS

After treatment with TOF and/or IGU, the arthritis scores, inflammatory cell infiltration in synovial tissues, and levels of interleukin (IL)-18, IL-1β, and IL-6 in the plasma were remarkably increased in the CIA + TNF model and dramatically decreased in the combination group. The expression of pyroptosis-related proteins was significantly lower in the combination group than in the CIA + TNF group, and a consistent trend was observed in vitro. Bone destruction was significantly alleviated, and the bone turnover rate was remarkably increased in the combination group compared to that in the CIA + TNF model.

CONCLUSION

TOF + IGU alleviated the severity of RRA in the CIA + TNF rat model, relieving joint inflammation, reducing bone erosion, and suppressing pyroptosis. The combined application of TOF and IGU may have a superimposed therapeutic effect on RRA and secondary osteoporotic bone remodeling.

Geniposide augments apoptosis in fibroblast-like synoviocytes by restoring hypoxia-enhanced JNK-BNIP3-mediated autophagy

BACKGROUND

As the main effector cells of chronic inflammation and hyperplasia of synovium, fibroblast-like synoviocytes (FLSs) show abnormal proliferation and insufficient apoptosis in the hypoxic microenvironment, which is due to the increase of BNIP3-mediated autophagy. This study aimed to explore the mechanism of geniposide (GE) on hypoxia-induced hyper-proliferative FLSs with a focus on autophagy and the JNK-BNIP3 pathway.

METHODS

The dynamic changes of autophagy, apoptosis, and hypoxia-related proteins in adjuvant arthritis (AA) rats were detected by immunohistochemistry and Western blot. The proliferation, autophagy, apoptosis, and mitochondrial state of FLSs were detected by CCK-8, flow cytometry, immunofluorescence, and transmission electron microscopy, respectively. Western blot, qRT-PCR, and co-immunoprecipitation were used to detect the expression of the JNK-BNIP3 pathway.

RESULTS

The excessive accumulation of BNIP3 in the synovium of AA rats was accompanied by inhibition of apoptosis and an increase in autophagy. GE inhibited the expression of BNIP3, enhanced apoptosis, decreased autophagy, and improved chronic inflammation and hyperplasia of synovium. The amount of autophagy under different oxygen concentrations was the key to mediating the different survival rates of FLSs, and the inhibition of autophagy triggered apoptosis. GE suppressed the proliferation of FLSs and down-regulated autophagy, leading to the accumulation of ROS and the decrease of mitochondrial membrane potential, induced the increase of apoptosis, and suppressed the accumulation of BNIP3 and the hyperphosphorylation of JNK.

CONCLUSION

GE inhibited autophagy by restoring the hypoxia-induced activated JNK-BNIP3 pathway, inducing mitochondrial oxidative damage, augmented apoptosis, and decreased survival rate of FLSs.

Advances of the small molecule drugs regulating fibroblast-like synovial proliferation for rheumatoid arthritis

Rheumatoid arthritis (RA) is a type of chronic autoimmune and inflammatory disease. In the pathological process of RA, the alteration of fibroblast-like synoviocyte (FLS) and its related factors is the main influence in the clinic and fundamental research. In RA, FLS exhibits a uniquely aggressive phenotype, leading to synovial hyperplasia, destruction of the cartilage and bone, and a pro-inflammatory environment in the synovial tissue for perpetuation and progression. Evidently, it is a highly promising way to target the pathological function of FLS for new anti-RA drugs. Based on this, we summed up the pathological mechanism of RA-FLS and reviewed the recent progress of small molecule drugs, including the synthetic small molecule compounds and natural products targeting RA-FLS. In the end, there were some views for further action. Compared with MAPK and NF-κB signaling pathways, the JAK/STAT signaling pathway has great potential for research as targets. A small number of synthetic small molecule compounds have entered the clinic to treat RA and are often used in combination with other drugs. Meanwhile, most natural products are currently in the experimental stage, not the clinical trial stage, such as triptolide. There is an urgent need to unremittingly develop new agents for RA.

[Berberine inhibits autophagy and promotes apoptosis of fibroblast-like synovial cells from rheumatoid arthritis patients through the ROS/mTOR signaling pathway]

OBJECTIVE

To evaluate the regulatory effect of berberine on autophagy and apoptosis balance of fibroblast-like synoviocytes (FLSs) from patients with in rheumatoid arthritis (RA) and explore the mechanism.

METHODS

The inhibitory effect of 10, 20, 30, 40, 50, 60, 70, and 80 μmol/L berberine on RA-FLS proliferation was assessed using CCK-8 method. Annexin V/PI and JC-1 immunofluorescence staining was used to analyze the effect of berberine (30 μmol/L) on apoptosis of 25 ng/mL TNF-α- induced RA-FLSs, and Western blotting was performed to detect the changes in the expression levels of autophagy- and apoptosis-related proteins. The cells were further treated with the autophagy inducer RAPA and the autophagy inhibitor chloroquine to observe the changes in autophagic flow by laser confocal detection of mCherry-EGFP-LC3B. RA-FLSs were treated with the reactive oxygen species (ROS) mimic H2O2 or the ROS inhibitor NAC, and the effects of berberine on ROS, mTOR and p-mTOR levels were observed.

RESULTS

The results of CCK-8 assay showed that berberine significantly inhibited the proliferation of RA-FLSs in a time- and concentration-dependent manner. Flow cytometry and JC-1 staining showed that berberine (30 μmol/L) significantly increased apoptosis rate (P < 0.01) and reduced the mitochondrial membrane potential of RA-FLSs (P < 0.05). Berberine treatment obviously decreased the ratios of Bcl-2/Bax (P < 0.05) and LC3B-II/I (P < 0.01) and increased the expression of p62 protein in the cells (P < 0.05). Detection of mCherry-EGFP-LC3B autophagy flow revealed obvious autophagy flow block in berberine-treated RA-FLSs. Berberine significantly reduced the level of ROS in TNF-α-induced RA-FLSs and upregulated the expression level of autophagy-related protein p-mTOR (P < 0.01); this effect was regulated by ROS level, and the combined use of RAPA significantly reduced the pro-apoptotic effect of berberine in RA-FLSs (P < 0.01).

CONCLUSION

Berberine can inhibit autophagy and promote apoptosis of RA-FLSs by regulating the ROS-mTOR pathway.

Targeting fibroblast-like synoviocytes in rheumatoid arthritis

Fibroblast-like synoviocytes (FLS) are mesenchymal-derived cells that play an important role in the physiology of the synovium by producing certain components of the synovial fluid and articular cartilage. In rheumatoid arthritis (RA), however, fibroblasts become a key driver of synovial inflammation and joint damage. Because of this, there has been recent interest in FLS as a therapeutic target in RA to avoid side effects such as systemic immune suppression associated with many existing RA treatments. In this review, we describe how approved treatments for RA affect FLS signaling and function and discuss the effects of investigational FLS-targeted drugs for RA.

Celastrol inhibits rheumatoid arthritis by inducing autophagy via inhibition of the PI3K/AKT/mTOR signaling pathway

OBJECTIVE

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disorder of the synovial joints. Celastrol (Cel) is a quinone-methylated triterpenoid extracted from Tripterygium wilfordii Hook F (TwHF) that has been proven to be effective in treating RA. However, the underlying molecular mechanism of celastrol in the treatment of RA remains unknown. This study explored the protective effect of celastrol against RA and the specific mechanisms of celastrol in vitro and in vivo.

METHODS

A chicken type II collagen (CII)-induced arthritis (CIA) mouse model was used to explore the anti-arthritic effects of celastrol, and paw swelling degree, the poly-arthritis index score and serum cytokine levels were determined. Pathological morphology was observed using hematoxylin and eosin (H&E) staining. The influences of celastrol on the proliferation of tumor necrosis factor-α (TNF-α)-induced fibroblast-like synoviocytes (FLSs) were tested by Cell Counting Kit-8 (CCK-8) assays and5-ethynyl-2'-deoxyuridine (EdU) staining assays. The level of autophagy was detected by transmission electron microscopy (TEM). Furthermore, the PI3K/AKT/mTOR pathway and the status of autophagy in the CIA model and FLSs were also detected by western blot and immunofluorescence staining.

RESULTS

The results showed that celastrol decreased arthritis severity and inhibited TNF-α-induced FLSs proliferation. Additionally, celastrol decreased the secretion of pro-inflammatory cytokines. Moreover, celastrol increased autophagosome levels and LC3B protein expression in TNF-α-treated FLSs. Furthermore, celastrol increased the protein expression of LC3-II and Beclin-1 and decreased the phosphorylation degree of mTOR and AKT.

CONCLUSION

In conclusion, our findings confirmed that celastrol ameliorates RA via the up-regulation of autophagy by inhibiting the PI3K/AKT/mTOR axis.

IL-27 regulates autophagy in rheumatoid arthritis fibroblast-like synoviocytes via STAT3 signaling

Rheumatoid arthritis (RA) is a highly prevalent autoimmune condition associated with pronounced synovial inflammation. The majority of RA patients required long-term treatment to control disease progression, thus imposing a significant financial burden on affected individuals. The development of RA is critically influenced by fibroblast-like synoviocytes (FLSs) within the synovial lining. IL-27 is an IL-6/IL-12 family cytokine that has recently been shown to play varied pro-inflammatory or protective roles in particular autoimmune diseases. However, the effects of IL-27 on FLSs in the context of RA have yet to be clarified and warrant further research. This study was developed to evaluate the impact of IL-27 treatment on apoptotic and autophagic activity in RA-associated FLSs, with a particular focus on the role of the STAT3 pathway in this regulatory context. Through these experiments, we found that IL-27 was able to suppress FLS proliferation and autophagic activity, with a high dose of this cytokine (100 ng/mL) markedly suppressing autophagy while simultaneously inducing some level of cellular apoptosis. The STAT3 inhibitor STA21 was found to reverse the IL-27-mediated suppression of autophagic activity in these RA-associated FLSs. Imbalanced cellular proliferation and apoptosis is of critical importance in the context of RA progression, and we found that IL-27 was able to regulate such imbalance and to enhance the apoptotic activity of RA FLSs by inhibiting rapamycin-activated autophagy. Together, these results indicate that IL-27 can regulate autophagic activity within RA-associated FLSs via the STAT3 signaling pathway, leading to inhibition of cellular proliferation.