Urinary exosomal miR-146a as a marker of albuminuria, activity changes and disease flares in lupus nephritis.

BACKGROUND: Urinary exosomes, especially microRNAs (miRNAs) packaged within, are ideal sources of renal damage markers. We investigated the association between exosomal miR-146a, (anti-inflammatory regulator) and disease activity, proteinuria and systemic lupus erythematosus (SLE) flares over a 36-month follow-up period. METHODS: We isolated urinary exosomes from 41 SLE patients, 27 with lupus nephritis (LN) and 20 healthy controls, and exosomal miR-146a, quantified by the real-time quantitative polymerase chain reaction (RT-qPCR), was correlated with histological features in 13 renal biopsies. We also analysed the association between the exosomal miR-146a and TRAF6 axis. RESULTS: Exosomal miR-146a showed an inverse association with circulating C3 and C4 complement components, proteinuria, and with histological features such as chronicity index. This marker was able to identify LN with an AUC of 0.82 (p = 0.001). Basal exosomal miR-146a was associated with disease activity and proteinuria changes and was an independent marker of 36-month follow-up flares (OR 7.08, p = 0.02). Pathway analysis identified IRAK1 and TRAF6 as miR-146a target genes. Finally, in vitro experiments suggested that miR-146a exerts a protective effect through negative regulation of inflammation by suppressing IRAK1 and TRAF6. CONCLUSIONS: Urinary exosomal miR-146a levels are correlated with lupus activity, proteinuria and histological features, discriminating patients with LN and being a good baseline marker of SLE flares. We have identified a relevant biological miR-146a-TRAF6 axis association in LN renal fibrosis progression.

Decreased Urinary Levels of SIRT1 as Non-Invasive Biomarker of Early Renal Damage in Hypertension.

Sirtuins have become important players in renal damage in hypertension and diabetes, but their value as biomarkers is poorly assessed. The aims of the study were to evaluate the levels of sirtuin1 (SIRT1), and two miRNAs that regulate SIRT1 expression in hypertensive patients with incipient renal damage with and without diabetes. We quantified urinary SIRT1 and claudin 1 (CLDN1) mRNA and miR34-a and miR-200a levels by quantitative real-time polymerase chain reaction (RT-qPCR) from patients and in cultured podocytes treated with high glucose and angiotensin II. Western blot and fluorescence analyses were also performed. We found decreased SIRT1 levels in patients with increased urinary albumin excretion (UAE), the lowest with diabetes presence, and a strong association with UAE, discriminating incipient renal damage. In vitro experiments also showed SIRT1 overall decreases in podocyte cultures under treatment conditions. In urine samples, miR-34a was reduced and miR-200a increased, both related to UAE levels. However, both miRNAs were generally increased in podocyte cultures under high glucose and angiotensin-II treatment. These results show a significant urinary SIRT1 decrease in albuminuric hypertensive patients, strongly associated with albuminuria, suggesting that SIRT1 could be a potential and non-invasive method to assess incipient renal damage in hypertensive patients.

Creencias irracionales, rendimiento y deserción académica en ingresantes universitarios / Irrational beliefs, academic performance and academic desertion in university candidates

El ingreso a una carrera universitaria constituye un proceso de transición en el que pueden desarrollarse creencias irracionales que obstaculicen el desempeño y la permanencia en los estudios. En efecto, las creencias irracionales denotan la existencia de pensamientos rígidos, ilógicos y dogmáticos que pueden afectar el funcionamiento psicosocial de los ingresantes. Tomando esto en consideración, se desarrolló un estudio no experimental tendiente a examinar la relación entre creencias irracionales, rendimiento y deserción universitaria en una muestra de ingresantes universitarios (n=31). Aunque no se obtuvo una correlación significativa con el rendimiento académico (rs = -.17; p>.5), se observó que los estudiantes que abandonaban la universidad presentaban mayores creencias irracionales (U=28.00; Z=2.24; p<.05). Los resultados obtenidos fundamentan la importancia de llevar a cabo intervenciones preventivas con el fin de entrenar a los ingresantes en el control y gestión de creencias, favoreciendo así su adaptación académica y persistencia en los estudios.

Entering university implies a transitional process in which it can develop irrational beliefs. These beliefs can impair academic performance and the permanence in college. In fact, irrational beliefs reveal the existence of rigid, illogic and dogmatic thoughts that may affect on student’s psychosocial functioning. Considering this, we developed a no experimental study to examine the relationship between irrational beliefs, academic performance and desertion in university students (N=31). Although the relationship between irrational beliefs and academic performance is not significant (rs = -.17; p>.5), we observed that students who abandoned the university course showed greater irrational beliefs (U=28.00; Z=2.24; p<.05). Results obtained show the importance of preventive interventions regarding students training in controlling and managing cognitive beliefs for a better adaptation in academic environments and the permanence in university studies.