Similar effect of co-administration of methotrexate and folic acid for the treatment of arthritis compared to separate administration

OBJECTIVES

Methotrexate (MTX) is the recommended first-line treatment for rheumatoid arthritis associated with folic acid (FA) to reduce side effects related to MTX. Here, we proposed to test a co-administration of MTX with FA in the rat adjuvant-induced arthritis (AIA) on efficacy.

METHODS

AIA was induced in female Lewis rats and treated with MTX in 3 groups. The first group of rats received only MTX (n = 13), whereas the second received MTX and FA on the same day (n = 14). The third group received FA one day after MTX (n = 14). Arthritic index (AI), ankle circumference (AC), ankle microcomputed tomography, and blood tests assessed arthritis severity and MTX tolerance.

RESULTS

AI and AC were similar in MTX groups at various time points. Bone erosion and bone loss parameters were similar in all groups. MTX-PG1 was found at similar levels in various MTX groups and correlated negatively with arthritis severity. Finally, hematology and metabolic parameters were found at a similar level in MTX groups.

CONCLUSION

Co-administration of MTX with FA on the same day did not reduce efficacy compared to FA application one day after MTX. Thus, co-administration of MTX and FA could be more convenient and improve compliance in patients.

POS0695 EFFECT OF METHOTREXATE AND FOLIC ACID CO-ADMINISTRATION IN ARTHRITIS

Background

Methotrexate (MTX) is the recommended first-line treatment for rheumatoid arthritis. Adjuvant-induced arthritis (AIA) rat is a robust model with a high prevalence of arthritis used to investigate arthritis. MTX reduces inflammation, but associated with adverse events, such as gastrointestinal, hepatic, and hematology toxicity (1). To reduce these side effects, folic acid (FA) is administrated at distance to MTX with no defined recommendation for its dosing (5-25mg/week) or time point of administration (2) (1-3 days after MTX application). Whether the complicated therapeutic regimen with MTX once a week and FA at another time point affects compliance is an open question. MTX is metabolized in polyglutamates derivates (MTX-PG), which is a biomarker of MTX efficacy as its half-life (1-4 weeks) is longer than MTX (4h) (3).

Objectives

The aim of this study was to assess efficacy and tolerance of co-administration of MTX and FA compared to MTX with FA applied one day after MTX in the AIA.

Methods

Female Lewis rat were randomly divided in three groups and received an injection of Mycobacterium butyricum defining day (D) 0 to induce arthritis. An historic AIA group was used as control. Treatment began on D9, one day before arthritis onset in this model. The first group rats were treated with MTX only (n=13), the second group received MTX and FA at the same day (n=14), and the third group received FA one day after MTX administration (n=14). MTX was administrated intraperitoneally (IP) at 1 mg/kg every 3 days (4) and FA was delivered IP at 0.17 mg/kg. Arthritic index (AI) and ankle circumference (AC) were monitored to assess arthritis. Microcomputed tomography of the ankle was performed to assess bone loss. Moreover, complete blood count, transaminases, and MTX-PG were assessed.

Results

Arthritis developed at D10 in all groups. AI and AC were similar in MTX groups at the various time points. At D17, arthritis severity was lower in MTX groups (AI (mean and standard deviation): 1.4 ± 1.6; AC: 35 ± 7 mm) compared to AIA historical group (AI: 3.3 ± 0.6; AC: 42 ± 4 mm). Bone erosion and bone loss parameters were similar in all groups. Cortical porosity was around 0.40% ± 0.15 and bone volume / total volume was around 0.22% ± 0.13. MTX-PG1 was found at similar levels in MTX groups and correlated negatively with AI in MTX alone or MTX and FA at the same day groups (p<0.05 and p<0.01, respectively). Finally, white and red blood cells, platelets, hemoglobin, mean corpuscular volume, transaminases, and creatinine were found at a similar level in MTX groups.

Conclusion

Co-administration of MTX with FA on the same day is effective compared to FA application one day after MTX. MTX metabolism was not affected, as demonstrated by the MTX-PG concentrations. The biological tolerance between the protocols was comparable. Thus, co-administration of MTX and FA seems to be possible and may be more convenient to the patients and improve compliance at the end.

References

[1]Albrecht K, Müller-Ladner U. Side effects and management of side effects of methotrexate in rheumatoid arthritis. Clin Exp Rheumatol 2010;28:S95-101.

[2]Gaujoux-Viala C, et al. Recommendations of the French Society for Rheumatology for managing rheumatoid arthritis. Joint Bone Spine 2014;81:287–297.

[3]Angelis-Stoforidis P, et al. Methotrexate polyglutamate levels in circulating erythrocytes and polymorphs correlate with clinical efficacy in rheumatoid arthritis. Clin Exp Rheumatol 1999;17:313–320.

[4]Le Goff B, et al. A combination of methotrexate and zoledronic acid prevents bone erosions and systemic bone mass loss in collagen induced arthritis. Arthritis Res Ther 2009;11:R185.

Acknowledgements

We thank Ghislaine Roux, Diane Denis and Valentine Berrucas for their support in animal experiments. We thank Xavier Delavenne for MTX-PG dosage. We thank Nadia Boutahar for transaminases and creatinine dosage.

Disclosure of Interests

Elisa Dalix Grant/research support from: GEBRO, Mathieu Maalouf Grant/research support from: GEBRO, Sylvie Peyroche Grant/research support from: GEBRO, Arnaud Vanden-Bossche Grant/research support from: GEBRO, Charles-Antoine Arthaud Grant/research support from: GEBRO, Sophie Hodin Grant/research support from: GEBRO, Hubert MAROTTE Grant/research support from: GEBRO, Nordic Pharma, Rüdiger Müller Grant/research support from: GEBRO, Nordic Pharma

Polarization of Femtosecond Laser for Titanium Alloy Nanopatterning Influences Osteoblastic Differentiation

Ultrashort pulse lasers have significant advantages over conventional continuous wave and long pulse lasers for the texturing of metallic surfaces, especially for nanoscale surface structure patterning. Furthermore, ultrafast laser beam polarization allows for the precise control of the spatial alignment of nanotextures imprinted on titanium-based implant surfaces. In this article, we report the biological effect of beam polarization on human mesenchymal stem cell differentiation. We created, on polished titanium-6aluminum-4vanadium (Ti-6Al-4V) plates, a laser-induced periodic surface structure (LIPSS) using linear or azimuthal polarization of infrared beams to generate linear or radial LIPSS, respectively. The main difference between the two surfaces was the microstructural anisotropy of the linear LIPSS and the isotropy of the radial LIPSS. At 7 d post seeding, cells on the radial LIPSS surface showed the highest extracellular fibronectin production. At 14 days, qRT-PCR showed on the same surface an increase in osteogenesis-related genes, such as alkaline phosphatase and osterix. At 21 d, mineralization clusters indicative of final osteoinduction were more abundant on the radial LIPSS. Taken together, we identified that creating more isotropic than linear surfaces enhances cell differentiation, resulting in an improved osseointegration. Thus, the fine tuning of ultrashort pulse lasers may be a promising new route for the functionalization of medical implants.

Improvement of Pain Management by Nefopam in a Rat Adjuvant-Induced Arthritis Model

Introduction

The adjuvant-induced arthritis (AIA) model is widely used in research to investigate arthritis pathogenesis. Hind paw inflammation is the main outcome in this model with high loss of mobility function partly related to pain. However, analgesics such as non-steroidal anti-inflammatory drugs or opioid drugs interfere with the inflammation process related to arthritis, thus reducing their beneficial use in this model. Therefore, we investigated the effect of nefopam on arthritis development in order to improve pain management in the AIA model.

Methods

Female Lewis rats were randomly divided into two groups, and each group received an injection of Mycobacterium butyricum on defining day (D) 0. At D6, rats (n = 10) received nefopam (intraperitoneally or orally) or NaCl 0.9% IP or 1% sucrose in water (n = 5 for each). Rats were monitored with the arthritic index (AI) and ankle circumference. Pain was assessed by scoring based on behavioral indicators. Histology, RT-qPCR, and microcomputed tomography were performed.

Results

The clinical parameter AI and ankle circumference were not different in both groups at various time points. However, pain score was significantly lower in the nefopam group at the early stage of the disease. At a later stage of the disease, inflammation was mildly lower whereas bone erosion and bone loss parameters increased in the nefopam group.

Conclusion

Nefopam provided a slight reduction in the level of pain at the arthritis onset without reducing arthritis severity and bone loss in the rat AIA model. However, it should be administrated orally for a shorter period to avoid inflammation reduction in the long run.

YAP Transcriptional Activity Dictates Cell Response to TNF In Vitro

YAP/TAZ are transcription co-factors recently described responsive to pro-inflammatory cytokines and involved in inflammatory-related disorders. However, the role of tumor necrosis factor (TNF), a major pro-inflammatory cytokine, on YAP signaling is not well understood and controversial. Here, we observe in vitro, using wild type and YAP knockout HEK293 cells, that TNF triggers YAP nuclear translocation and transcriptional activity, thus being dependent on Rho family of GTPases. In response to TNF, YAP transcriptional activity orientates cell fate toward survival. Transcriptional analysis with Nanostring technology reveals that YAP modulates TNF-induced increase in fibro-inflammatory pathways such as NF-κB, inflammasomes, cytokines or chemokines signaling and pro-fibrotic pathways involving TGF-β and extracellular matrix remodeling. Therefore, in response to TNF, YAP acts as a sustainer of the inflammatory response and as a molecular link between inflammation and fibrotic processes. This work identifies that YAP is critical to drive several biological effects of TNF which are involved in cancer and inflammatory disorders.

YAP/TAZ: Key Players for Rheumatoid Arthritis Severity by Driving Fibroblast Like Synoviocytes Phenotype and Fibro-Inflammatory Response

Objective

The role of YAP/TAZ, two transcriptional co-activators involved in several cancers, was investigated in rheumatoid arthritis (RA).

Methods

Fibroblast like synoviocytes (FLS) from patients with RA or osteoarthritis were cultured in 2D or into 3D synovial organoids. Arthritis rat model (n=28) and colitis mouse model (n=21) were used. YAP/TAZ transcriptional activity was inhibited by verteporfin (VP). Multiple techniques were used to assess gene and/or protein expression and/or localization, cell phenotype (invasion, proliferation, apoptosis), bone erosion, and synovial stiffness.

Results

YAP/TAZ were transcriptionally active in arthritis (19-fold increase for CTGF expression, a YAP target gene, in RA vs. OA organoids; p<0.05). Stiff support of culture or pro-inflammatory cytokines further enhanced YAP/TAZ transcriptional activity in RA FLS. Inhibiting YAP/TAZ transcriptional activity with VP restored a common phenotype in RA FLS with a decrease in apoptosis resistance, proliferation, invasion, and inflammatory response. Consequently, VP blunted hyperplasic lining layer formation in RA synovial organoids. In vivo, VP treatment strongly reduced arthritis severity (mean arthritic index at 3.1 in arthritic group vs. 2.0 in VP treated group; p<0.01) by restoring synovial homeostasis and decreasing systemic inflammation. YAP/TAZ transcriptional activity also enhanced synovial membrane stiffening in vivo, thus creating a vicious loop with the maintenance of YAP/TAZ activation over time in FLS. YAP/TAZ inhibition was also effective in another inflammatory model of mouse colitis.

Conclusion

Our work reveals that YAP/TAZ were critical factors during arthritis. Thus, their transcriptional inhibition could be relevant to treat inflammatory related diseases.