Leishmania braziliensis exosomes activate human macrophages to produce proinflammatory mediators.

Exosomes, organelles measuring 30-200nm, are secreted by various cell types. Leishmania exosomes consist of many proteins, including heat shock proteins, annexins, Glycoprotein 63, proteins exerting signaling activity and those containing mRNA and miRNA. Studies have demonstrated that Leishmania donovani exosomes downregulate IFN-γ and inhibit the expression of microbicidal molecules, such as TNF and nitric oxide, thus creating a microenvironment favoring parasite proliferation. Despite lacking immunological memory, data in the literature suggest that, following initial stimulation, mononuclear phagocytes may become "trained" to respond more effectively to subsequent stimuli. Here we characterized the effects of macrophage sensitization using L. braziliensis exosomes prior to infection by the same pathogen. Human macrophages were stimulated with L. braziliensis exosomes and then infected with L. braziliensis. Higher levels of IL-1ß and IL-6 were detected in cultures sensitized prior to infection compared to unstimulated infected cells. Moreover, stimulation with L. braziliensis exosomes induced macrophage production of IL-1ß, IL-6, IL-10 and TNF. Inhibition of exosome secretion by L. braziliensis prior to macrophage infection reduced cytokine production and produced lower infection rates than untreated infected cells. Exosome stimulation also induced the consumption/regulation of NLRP3 inflammasome components in macrophages, while the blockade of NLRP3 resulted in lower levels of IL-6 and IL-1ß. Our results suggest that L. braziliensis exosomes stimulate macrophages, leading to an exacerbated inflammatory state that may be NLRP3-dependent.

Prostaglandin E2 contributes to L. braziliensis survival and therapeutic failure in cutaneous leishmaniasis.

Patients with cutaneous leishmaniasis (CL) present an exacerbated inflammatory response associated with tissue damage and ulcer development. In recent years, higher rates of failure to pentavalent antimoniate therapy have been observed, yet the underlying reason remains poorly understood. We hypothesize that the eicosanoid PGE2 favours the establishment of infection by L. braziliensis, which contributes to therapeutic failure. The aim of the present study was to investigate the influence of PGE2 on the survival of L. braziliensis in macrophages and rates of therapeutic failure in CL patients. PGE2, an eicosanoid derived from the metabolism of arachidonic acid by the COX-2 enzyme, plays several roles in immune response. We found that increased PGE2 decreases the microbicidal function of macrophages and is associated with disease severity and therapeutic failure. Additionally, the neutralization of COX-2 by NS398, a selective NSAID, increases the ability of macrophages to kill L. braziliensis and protects against the pathological inflammatory response. Our data suggest that NS398 may serve as an adjunct treatment for CL patients.

Molecular analysis of the beta-catenin gene in patients with the Mayer-Rokitansky-Küster-Hauser syndrome.

PURPOSE: To study the beta-catenin gene in a group of Mayer-Rokitansky-Küster-Hauser patients. METHODS: Twelve patients with the Mayer-Rokitansky-Küster-Hauser syndrome were included in this study. DNA was extracted from peripheral blood and the region codifying beta-catenin GSK-3beta phosphorylation sites on exon 3 was amplified. PCR products were purified and directly sequenced. RESULTS: No mutations were found in the GSK-3beta phosphorylation sites on exon 3 of beta-catenin gene in this group of patients with the MRKH syndrome. CONCLUSIONS: beta-catenin gene mutations are an unlikely cause of the MRKH syndrome.

Effect of a combination of ethinylestradiol 30 microg and drospirenone 3 mg on tolerance, cycle control, general well-being and fluid-related symptoms in women with premenstrual disorders requesting contraception.

PURPOSE: Positive effects on premenstrual symptoms have been observed with low-dose oral contraceptives. Drospirenone is a synthetic progestogen with antiandrogenic and antimineralocorticoid effects. This open-label, multicenter study evaluated the effects of a combination of ethinylestradiol 30 microg and drospirenone 3 mg on safety, cycle control, general well-being and fluid-related symptoms in women with premenstrual disorders requesting contraception. MATERIALS AND METHODS: A total of 241 healthy volunteers with symptoms of premenstrual disorder was enrolled in the study. Of the final sample, 203 completed the six-cycle treatment and were included in the efficacy analysis whereas 236 were included in the tolerability analysis. The subjects recruited to the study were required to fill up the Psychological General Well-Being Index (PGWBI). RESULTS: There was no significant change in body weight or blood pressure throughout the treatment. Adverse events reported by patients during treatment consisted of those already known to be associated with oral contraceptive use. PGWBI scores were significantly higher after six cycles of treatment compared with baseline values (p<.0001). A total of 198 (84.2%) subjects reported a great improvement in premenstrual symptoms. CONCLUSIONS: The results of this study confirm that oral use of a combination of ethinylestradiol 30 microg and drospirenone 3 mg provides good cycle control, is well tolerated and has a positive impact on symptoms of premenstrual disorder.