Cell phenotypes as activity biomarkers in patients with Systemic Lupus Erythematosus

Abstract The pathogenesis of systemic lupus erythematosus (SLE) is complex. Few studies in Brazilian population have addressed cell phenotypes associated with immunological responses and their associations with SLE activity. The aim of this study is to investigate cell phenotypes associated to SLE diagnosis, treatment and activity. Twenty-eight SLE female patients (17 inactive, 11 active) and 10 healthy women were included in this study. Markers of natural killer (Nk), T and B cells in peripheral blood were evaluated by flow cytometry. Nkt cells were decreased only in SLE active patients. Activated CD4+, regulatory T FoxP3+ and B cells were decreased in both active and inactive SLE patients, compared to control group. The data corroborate the disruption of immune regulatory response in SLE patients and suggest phenotipic changes as possible biomarkers of SLE activity.

In the View of Endothelial Microparticles: Novel Perspectives for Diagnostic and Pharmacological Management of Cardiovascular Risk during Diabetes Distress.

Acute or chronic exposure to diabetes-related stressors triggers a specific psychological and behavior stress syndrome called diabetes distress, which underlies depressive symptoms in most diabetic patients. Distressed and/or depressive diabetic adults exhibit higher rates of cardiovascular mortality and morbidity, which have been correlated to macrovascular complications evoked by diabetic behavior stress. Recent experimental findings clearly point out that oxidative stress accounts for the vascular dysfunction initiated by the exposure to life stressors in diabetic conditions. Moreover, oxidative stress has been described as the main autocrine and paracrine mechanism of cardiovascular damage induced by endothelial microparticles (anuclear ectosomal microvesicles released from injured endothelial cells) in diabetic subjects. Such robust relationship between oxidative stress and cardiovascular diseases strongly suggests a critical role for endothelial microparticles as the primer messengers of the redox-dependent vascular dysfunction underlying diabetes distress. Here, we provide novel perspectives opened in the view of endothelial microparticles as promising diagnostic and pharmacotherapeutic biomarkers of cardiovascular risk in distressed diabetic patients.

New Horizons on Molecular Pharmacology Applied to Drug Discovery: When Resonance Overcomes Radioligand Binding.

One of the cornerstones of rational drug development is the measurement of molecular parameters derived from ligand-receptor interaction, which guides therapeutic windows definition. Over the last decades, radioligand binding has provided valuable contributions in this field as key method for such purposes. However, its limitations spurred the development of more exquisite techniques for determining such parameters. For instance, safety risks related to radioactivity waste, expensive and controlled disposal of radioisotopes, radiotracer separation-dependence for affinity analysis, and one-site mathematical models-based fitting of data make radioligand binding a suboptimal approach in providing measures of actual affinity conformations from ligands and G proteincoupled receptors (GPCR). Current advances on high-throughput screening (HTS) assays have markedly extended the options of sparing sensitive ways for monitoring ligand affinity. The advent of the novel bioluminescent donor NanoLuc luciferase (Nluc), engineered from Oplophorus gracilirostris luciferase, allowed fitting bioluminescence resonance energy transfer (BRET) for monitoring ligand binding. Such novel approach named Nluc-based BRET (NanoBRET) binding assay consists of a real-time homogeneous proximity assay that overcomes radioligand binding limitations but ensures the quality in affinity measurements. Here, we cover the main advantages of NanoBRET protocol and the undesirable drawbacks of radioligand binding as molecular methods that span pharmacological toolbox applied to Drug Discovery. Also, we provide a novel perspective for the application of NanoBRET technology in affinity assays for multiple-state binding mechanisms involving oligomerization and/or functional biased selectivity. This new angle was proposed based on specific biophysical criteria required for the real-time homogeneity assigned to the proximity NanoBRET protocol.