title: Methotrexate-loaded lipid-core nanocapsules are highly effective in the control of inflammation in synovial cells and a chronic arthritis model.
abstract: BACKGROUND
  Rheumatoid arthritis (RA) is the most common autoimmune disease in the word, affecting 1% of the population. Long-term prognosis in RA was greatly improved following the introduction of highly effective medications such as methotrexate (MTX). Despite the importance of this drug in RA, 8%-16% of patients must discontinue the treatment because of adverse effects. Last decade, we developed a promising new nanocarrier as a drug-delivery system, lipid-core nanocapsules.
  
  
  OBJECTIVE
  The aim of the investigation reported here was to evaluate if methotrexate-loaded lipid-core nanocapsules (MTX-LNC) reduce proinflammatory and T-cell-derived cytokines in activated mononuclear cells derived from RA patients and even in functional MTX-resistant conditions. We also aimed to find out if MTX-LNC would reduce inflammation in experimentally inflammatory arthritis at lower doses than MTX solution.
  
  
  METHODS
  Formulations were prepared by self-assembling methodology. The adjuvant arthritis was induced in Lewis rats (AIA) and the effect on edema formation, TNF-α levels, and interleukin-1 beta levels after treatment was evaluated. Mononuclear cells obtained from the synovial fluid of RA patients during articular infiltration procedures were treated with MTX solution and MTX-LNC. For in vitro experiments, the same dose of MTX was used in comparing MTX and MTX-LNC, while the dose of MTX in the MTX-LNC was 75% lower than the drug in solution in in vivo experiments.
  
  
  RESULTS
  Formulations presented nanometric and unimodal size distribution profiles, with D[4.3] of 175±17 nm and span of 1.6±0.2. Experimental results showed that MTX-LNC had the same effect as MTX on arthritis inhibition on day 28 of the experiment (P<0.0001); however, this effect was achieved earlier, on day 21 (P<0.0001), by MTX-LNC, and this formulation had reduced both TNF-α (P=0.001) and IL-1α (P=0.0002) serum levels by the last day of the experiment. Further, the MTX-LNC were more effective at reducing the cytokine production from mononuclear synovial cells than MTX.
  
  
  CONCLUSIONS
  The MTX-LNC were better than the MTX solution at reducing proinflammatory cytokines and T-cell-derived cytokines such as interferon-gamma and interleukin-17A. This result, combined with the reduction in the dose required for therapy, shows that MTX-LNC are a very promising system for the treatment of RA.
authors.affiliation: Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal do Amazonas, Manaus, Brazil ; Programa de Pós-Graduação e Imunologia Básica e Aplicada, Universidade Federal do Amazonas, Manaus, Brazil.
authors.forename: Antônio Luiz
authors.initials: AL
authors.lastname: Boechat
authors.affiliation: Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Porto Alegre, Brazil.
authors.forename: Catiúscia Padilha
authors.initials: CP
authors.lastname: de Oliveira
authors.affiliation: Programa de Pós-Graduação e Imunologia Básica e Aplicada, Universidade Federal do Amazonas, Manaus, Brazil.
authors.forename: Andrea Monteiro
authors.initials: AM
authors.lastname: Tarragô
authors.affiliation: Programa de Pós-Graduação e Imunologia Básica e Aplicada, Universidade Federal do Amazonas, Manaus, Brazil.
authors.forename: Allyson Guimarães
authors.initials: AG
authors.lastname: da Costa
authors.affiliation: Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal do Amazonas, Manaus, Brazil ; Programa de Pós-Graduação e Imunologia Básica e Aplicada, Universidade Federal do Amazonas, Manaus, Brazil.
authors.forename: Adriana
authors.initials: A
authors.lastname: Malheiro
authors.affiliation: Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Porto Alegre, Brazil.
authors.forename: Silvia Stanisçuaski
authors.initials: SS
authors.lastname: Guterres
authors.affiliation: Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Porto Alegre, Brazil ; Departamento de Química Orgânica, Instituto de Química, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Adriana Raffin
authors.initials: AR
authors.lastname: Pohlmann
mesh_terms: D000818:Animals; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000276:immunology / Q000378:metabolism; D002908:Chronic Disease; D004195:Disease Models, Animal; D004337:Drug Carriers / Q000737:chemistry*; D006801:Humans; D007249:Inflammation / Q000188:drug therapy; D007371:Interferon-gamma / Q000378:metabolism; D020381:Interleukin-17 / Q000378:metabolism; D008055:Lipids / Q000737:chemistry*; D008727:Methotrexate / Q000008:administration & dosage / Q000737:chemistry* / Q000494:pharmacology* / Q000627:therapeutic use; D053769:Nanocapsules / Q000737:chemistry*; D051381:Rats; D013583:Synovial Membrane / Q000187:drug effects* / Q000378:metabolism; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism
chemical_list: D004337:Drug Carriers; D020381:Interleukin-17; D008055:Lipids; D053769:Nanocapsules; D007371:Interferon-gamma; D008727:Methotrexate
keywords: IFN-γ; IL-1; IL-17A; IL-6; TNF-α; arthritis; cytokines; drug delivery; drug targeting