OBJECTIVES:Hydroxychloroquine is an antimalarial agent that has been used in systemic lupus erythematosus and rheumatoid arthritis treatment for many years. Recently, novel mechanisms of action have been proposed, thereby broadening the therapeutic perspective of this medication. The purpose of this study was to evaluate the immunomodulatory activity of hydroxychloroquine in T helper 17 (Th17) cytokines in healthy individuals and patients.METHODS:Eighteen female patients with systemic lupus erythematosus (mean age 39.0±12.9 years) and 13 female patients with rheumatoid arthritis (mean age 51.5±7.7 years) were recruited from Universidade Federal de Pernambuco-Brazil. The patients were included after fulfilling four classification criteria for systemic lupus erythematosus or rheumatoid arthritis from the American College of Rheumatology. After being stimulated with phorbol 12-myristate 13-acetate and ionomycin in the absence or presence of different concentrations of hydroxychloroquine, the interleukin 6, 17 and 22 levels were quantified with an enzyme-linked immunosorbent assay in culture supernatants of peripheral blood mononuclear cells from healthy individuals and patients.RESULTS:We demonstrated that in peripheral blood mononuclear cells from healthy volunteers and in systemic lupus erythematosus and rheumatoid arthritis patients, there was a significant reduction in the IL-6, IL-17 and IL-22 supernatant levels after adding hydroxychloroquine.CONCLUSIONSOur in vitro results demonstrated that hydroxychloroquine inhibits IL-6, IL-17 and IL-22 production and contributes to a better understanding of the mechanism of action of this medication.

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The immunological role of interleukin 27 has been reported in various inflammatory diseases, but its importance in systemic lupus erythematosus pathogenesis is not completely established. The aim of this study was to evaluate serum levels of IL-27 in SLE patients and its correlation with clinical manifestations and disease activity. IL-27 levels were assessed in 70 SLE patients and 30 healthy controls by ELISA. Clinical and laboratory parameters were recorded. Statistic analyzes were performed by Graph Prism 3.02 software. The IL-27 serum levels were significantly decreased in SLE patients compared with controls (mean 899.92 and 1,531.22 pg/ml, P=0.0005). There was a correlation between IL-27 levels and C3 levels (P=0.004). Nevertheless, there was no association of serum IL-27 levels with disease activity evaluated by SLEDAI score (P=0.9605). No significant difference was found regarding IL-27 levels between SLE patients with and without nephritis, haematuria, proteinuria and positive anti-dsDNA. Correlation analysis between serum IL-27 levels and SLEDAI, SLICC, proteinuria levels, C4 and CH50 levels also showed no association. These data demonstrated decreased serum levels of IL-27 in SLE patients but further studies are needed to clarify the precise role of this cytokine and its potential use as therapeutic target.

The current long-term treatment for leishmaniasis causes severe side effects and resistance in some cases. An evaluation of the anti-leishmanial potential of an HSP90-inhibitor, 17-allylamino-17-demethoxygeldanamycin (17-AAG), demonstrated its potent effect against Leishmania spp. in vitro and in vivo. We have previously shown that 17-AAG can kill L. (L) amazonensis promastigotes with an IC50 of 65 nM and intracellular amastigote at concentrations as low as 125 nM. As this compound presents low solubility and high toxicity in human clinical trials, we prepared an inclusion complex containing hydroxypropyl-β-cyclodextrin and 17-AAG (17-AAG:HPβCD) to improve its solubility. This complex was characterized by scanning electron microscopy, and X-ray diffraction. Liposomes-containing 17-AAG:HPβCD was prepared and evaluated for encapsulation efficiency (EE%), particle size, polydispersity index (PDI), pH, and zeta potential, before and after accelerated and long-term stability testing. An evaluation of leishmanicidal activity against promastigotes and intracellular amastigotes of L. (L) amazonensis was also performed. The characterization techniques utilized confirmed the formation of the inclusion complex, HPβCD:17-AAG, with a resulting 33-fold-enhancement in compound water solubility. Stability studies revealed that 17-AAG:HPβCD-loaded liposomes were smaller than 200 nm, with 99% EE. Stability testing detected no alterations in PDI that was 0.295, pH 7.63, and zeta potential +22.6, suggesting liposome stability, and suitability for evaluating leishmanicidal activity. Treatment of infected macrophages with 0.006 nM of 17-AAG:HPβCD or 17-AAG:HPβCD-loaded liposomes resulted in almost complete amastigote clearance inside macrophages after 48 h. This reduction is similar to the one observed in infected macrophages treated with 2 μM amphotericin B. Our results showed that nanotechnology and drug delivery systems could be used to increase the antileishmanial efficacy and potency of 17-AAG in vitro, while also resulting in reduced toxicity that indicates these formulations may represent a potential therapeutic strategy against leishmaniasis.

Allergic asthma is a chronic, complex inflammatory disease of the airway. Despite extensive studies on the immunomodulation of T helper (Th) cell pathways (i.e., Th1 and Th2) in asthma, little is known about the effects of Th17 pathway modulation, particularly that involving peroxisome proliferator-activated receptors (PPARs). In response, two new thiazolidinedione derivatives-namely, LPSF-GQ-147 and LPSF-CR-35 were synthesized and evaluated for their immunomodulatory effects on Th17-related cytokines, including interferon γ (IFNγ), interleukin IL-6, IL-17, and IL-22 in the peripheral blood mononuclear cells of asthmatic children. Both compounds were nontoxic even at high concentrations (i.e., 100 µM). The LPSF-CR-35 compound significantly reduced the levels of IL-17A (p = .039) and IFNγ (p = .032) at 10 µM. For IL-22 and IL-6, significant reduction occurred at 100 µM (p = .039 and p = .02, respectively). Conversely, LPSF-GQ-147 did not significantly inhibit the production of the tested cytokines, the levels of all of which were more efficiently reduced by LPSF-CR-35 than methylprednisolone, the standard compound. Real-time polymerase chain reaction assay confirmed that LPSF-GQ-147 has significant PPARγ modulatory activity. Such data indicate that both LPSF-CR-35 and LPSF-GQ-147 are promising candidates as drugs for treating inflammation and asthma.