Reappraisal of Antimalarials in Interferonopathies: New Perspectives for Old Drugs

The story of antimalarials as antinflammatory drugs dates back several centuries. Chinin, the extract of the Cinchona bark, has been exploited since the 18th century for its antimalarial and antifebrile properties. Later, during the Second World War, the broad use of antimalarials allowed arguing their antirheumatic effect on soldiers. Since then, these drugs have been broadly used to treat Systemic Lupus Erythematosus, but, only recently, have the molecular mechanisms of action been partly clarified. Inhibitory action on vacuole function and trafficking has been considered for decades the main mechanism of the action of antimalarials, affecting the activation of phagocytes and dendritic cells. In addition, chloroquine is also known as a potent inhibitor of autophagy, providing another possible explanation of its antinflammatory action. However, much attention has been recently devoted to the action of antimalarials on the so-called cGAS-STING pathway leading from the sensing of cytoplasmic nucleic acids to the production of type I interferons. This pathway is a fundamental mechanism of host defence, since it is able to detect microbial DNA and induce the type I interferon-mediated immune response. Of note, genetic defects in the degradation of nucleic acids lead to inappropriate cGAS-STING activation and inflammation. These disorders, called type I interferonopathies, represent a valuable model to study the antinflammatory potential of antimalarials. We will discuss possible development of antimalarials to improve the treatment of type I interferonopathies and likely multifactorial disorders characterised by interferon inflammation, such as Systemic Lupus Erythematosus

Multicentric Case-Control Study on Azathioprine Dose and Pharmacokinetics in Early-onset Pediatric Inflammatory Bowel Disease

BACKGROUND: Early-onset inflammatory bowel disease (IBD) is generally aggressive, with a high probability of complications and need of surgery. Despite the introduction of highly effective biological drugs, treatment with azathioprine continues to be important even for early-onset IBD; however, in these patients azathioprine response seems to be reduced. This study evaluated azathioprine doses, metabolite concentrations, and their associations with patients' age in children with IBD treated at 6 tertiary pediatric referral centers. METHODS: Azathioprine doses, metabolites, and clinical effects were assessed after at least 3 months of therapy in 17 early-onset (age 12 and <18 yrs, controls) patients with IBD. Azathioprine dose was titrated on therapeutic efficacy (response and adverse effects). Azathioprine metabolites and thiopurine methyltransferase activity were determined by high-performance liquid chromatography with ultra violet-vis detection (HPLC-UV) methods. RESULTS: Frequency of patients in remission was similar among early-onset and control groups, respectively (82% and 84%, P value = 0.72). Early-onset patients required higher doses of azathioprine (median 2.7 versus 2.0 mg\ub7kg\ub7d, P value = 1.1 7 10). Different doses resulted in comparable azathioprine active thioguanine nucleotide metabolite concentrations (median 263 versus 366 pmol/8 7 10 erythrocytes, P value = 0.41) and methylmercaptopurine nucleotide concentrations (median 1455 versus 1532 pmol/8 7 10 erythrocytes, P value = 0.60). Lower ratios between thioguanine nucleotide metabolites and azathioprine doses were found in early-onset patients (median 98 versus 184 pmol/8 7 10 erythrocytes\ub7mg\ub7kg\ub7d, P value = 0.017). Interestingly, early-onset patients presented also higher thiopurine methyltransferase activity (median 476 versus 350 nmol methylmercaptopurine/mg hemoglobin/h, P-value = 0.046). CONCLUSIONS: This study demonstrated that patients with early-onset IBD present increased inactivating azathioprine metabolism, likely because of elevated activity of the enzyme thiopurine methyltransferase

Glucocorticoid pharmacogenetics in pediatric idiopathic nephrotic syndrome

Idiopathic nephrotic syndrome represents the most common type of primary glomerular disease in children: glucocorticoids (GCs) are the first-line therapy, even if considerable interindividual differences in thepir efficacy and side effects have been reported. Immunosuppressive and anti-inflammatory effects of these drugs are mainly due to the GC-mediated transcription regulation of pro- and anti-inflammatory genes. This mechanism of action is the result of a complex multistep pathway that involves the glucocorticoid receptor and several other proteins, encoded by polymorphic genes. Aim of this review is to highlight the current knowledge on genetic variants that could affect GC response, particularly focusing on children with idiopathic nephrotic syndrome

SXR rs3842689: a prognostic factor for steroid sensitivity or resistance in pediatric idiopathic nephrotic syndrome

AIM: of the study was to analyse the impact of SXR rs3842689 polymorphism on the response to corticosteroids in pediatric idiopathic nephrotic syndrome. PATIENTS & METHODS: 66 children (56 steroid-sensitive, ten steroid-resistant) were studied for SXR gene polymorphism distribution. RESULTS: Steroid sensitive patients accounted for 96% of cases with In/In polymorphism, but only for 53% of cases with Del/Del polymorphism At odds ratio analysis, Del/Del represented a clear risk factor of steroid resistance (OR: 20.57; p = 0.009), while In/In was a favourable prognostic factor of steroid sensitivity. CONCLUSION: The analysis of SXR polymorphism is a promising tool to predict both the favourable response to corticosteroids and the risk of developing steroid resistance

Contribution of Glutathione-S-Transferases to the Pharmacogenetics of Azathioprine

Azathioprine is a purine antimetabolite drug commonly used as immunomodulator in the treatment of various chronic inflammatory diseases, such as inflammatory bowel disease (IBD). Azathioprine is activated in vivo after reaction with reduced glutathione (GSH) and conversion to mercaptopurine. Although this reaction may occur spontaneously, the presence of the enzyme glutathione-S-transferase (GST), in particular of isoforms GST-A1/GST-A2 and GST-M1, can increase its speed, leading to a faster activation of azathioprine to active thioguanine nucleotides. Moreover, GSTs may contribute to azathioprine effects by modulating GSH consumption, oxidative stress and apoptosis. Indeed, in young patients with IBD, deletion of GST-M1, which determines reduced enzymatic activity, was recently associated with reduced sensitivity to azathioprine and reduced production of its active metabolites. Therefore, genetic polymorphisms in genes for GSTs may be useful to predict response to azathioprine even if more in vitro and clinical validation studies are needed

Un langage des patterns pour la ville européenne

National audienceLes patterns représentent des solutions opérationnelles générales qui ont évolué au fil du temps pour résoudre des catégories typiques de problèmes, constituant ainsi une forme d'intelligence collective. Cependant, il est important de ne pas les considérer simplement comme une liste d'où extraire à loisir de bonnes solutions de conception. Depuis les travaux fondateurs d'Alexander et al. (1977), nous reconnaissons l'impératif d'un langage des patterns - un système de patterns interconnectés - comme la méthode la plus cohérente pour intervenir dans un système complexe tel que la ville. Pour relever les défis de l’urbanisation du 21ème siècle, nous avons conçu un langage de 60 patterns spécifiques au contexte européen, permettant de produire une ville centrée sur les besoins du piéton, sobre et adaptative.Dans cette étude, le langage des patterns sera utilisé pour établir un diagnostic des formes urbaines de la petite ville de Drap (Alpes-Maritimes), une commune de 5000 habitants située dans le moyen-pays niçois

Failure of interferon-γ pre-treated mesenchymal stem cell treatment in a patient with crohn's disease

12noMesenchymal stem cells (MSC) are cells of stromal origin which exhibit unlimited self-renewal capacity and pluripotency in vitro. It has recently been observed that MSC may also exert a profound immunosuppressive and anti-inflammatory effect both in vitro and in vivo with consequent potential use in autoimmune disorders. We present the case of a patient suffering from childhood-onset, multidrug resistant and steroid-dependent Crohn's disease who underwent systemic infusions of MSC, which led to a temporary reduction in CCR4, CCR7 and CXCR4 expression by T-cells, and a temporary decrease in switched memory B-cells, In addition, following MSC infusion, lower doses of steroids were needed to inhibit proliferation of the patient's peripheral blood mononuclear cells. Despite these changes, no significant clinical benefit was observed, and the patient required rescue therapy with infliximab and subsequent autologous hematopoietic stem cell transplantation. The results of biological and in vitro observations after MSC use and the clinical effects of infusion are discussed, and a brief description is provided of previous data on MSC-based therapy in autoimmune disorders.openopenTaddio, Andrea; Tommasini, Alberto; Valencic, Erica; Biagi, Ettore; Decorti, Giuliana; De Iudicibus, Sara; Cuzzoni, Eva; Gaipa, Giuseppe; Badolato, Raffaele; Prandini, Alberto; Biondi, Andrea; Ventura, AlessandroTaddio, Andrea; Tommasini, Alberto; Valencic, Erica; Biagi, Ettore; Decorti, Giuliana; DE IUDICIBUS, Sara; Cuzzoni, Eva; Gaipa, Giuseppe; Badolato, Raffaele; Prandini, Alberto; Biondi, Andrea; Ventura, Alessandr

Deletion of Glutathione-S-Transferase M1 Reduces Azathioprine Metabolite Concentrations in Young Patients With Inflammatory Bowel Disease.

GOALS: To investigate, in young patients with inflammatory bowel disease (IBD) treated with azathioprine, the association between genetic polymorphisms of thiopurine-S-methyl-transferase (TPMT), inosine-triphosphate-pyrophosphatase (ITPA), and glutathione-S-transferases (GST), involved in azathioprine metabolism, the concentration of the main metabolites of azathioprine, thioguanine nucleotides (TGNs) and the methylated nucleotides (MMPN), and the dose of the medication. BACKGROUND: Azathioprine is widely used in IBD as an immunosuppressive agent, particularly to maintain remission in patients with steroid refractory disease. Azathioprine is a prodrug and requires conversion to its active form mercaptopurine, which has no intrinsic activity, and is activated by the enzymes of the purine salvage pathway to TGNs. Polymorphisms in genes of enzymes involved in azathioprine metabolism influence the efficacy and toxicity of treatment. STUDY: Seventy-five young patients with IBD treated with azathioprine at least for 3 months were enrolled and genotyped for the selected genes; for these patients, TGN and MMPN metabolites were measured by high performance liquid chromatography in erythrocytes. RESULTS: GST-M1 deletion was associated with lower TGN/dose ratio (P=0.0030), higher azathioprine dose requirement (P=0.022), and reduced response to therapy (P=0.0022). TPMT variant genotype was associated with lower MMPN concentration (P=0.0064) and increased TGN/dose ratio (P=0.0035). ITPA C94A polymorphism resulted in an increased MMPN concentration (P=0.037). CONCLUSIONS: This study describes the effect of candidate genetic polymorphisms in TPMT, ITPA, and GST-M1 on azathioprine pharmacokinetics in IBD patients, showing, for the first time, relevant effects of GST-M1 genotype on azathioprine metabolites concentration

Lymphocytes activation and proliferation after Tofa treatment.

<p>Cells were analysed after four days of incubation with Tofa (day 4) and four days after the withdrawal of the drug (day 4+4). The percentage of proliferating cells was assessed by measuring the level of CFSE fluorescence. Activation of cells is indicated as MFI of CD25. Data are expressed as mean ± SD of four independent experiments.</p

Absolute cell counts and viability.

<p>The plots on the left represent the absolute number of cells. Histograms on the right report the percentage of dead cells, as 7AAD positive cells. Counts and viability are reported for each subpopulation of interest, before treatment (day 0) and after the first four days of incubation in presence or absence of PHA and Tofa (day 4). Data are expressed as mean ± SD of two independent experiments.</p