Abstract (EN):
INTRODUCTION AND OBJECTIVES: Nerve Growth Factor
(NGF) may constitute a useful biomarker of OAB syndrome. Less is known about the role of Brain Derived Neurotrophic Factor (BDNF) in lower urinary tract function, although this is also an ubiquitous neurotrophin. Here, we described urinary NGF and BDNF in healthy volunteers to investigate physiological pattern of secretion and gender differences. Additionally, we assessed the urinary levels of NGF and
BDNF in OAB patients, before and after life-style counselling, and correlated them with the severity of symptoms.
METHODS: Urine samples from 40 healthy volunteers (20 men and 20 women) were collected in the morning, afternoon and evening.
The procedure was repeated 3 months later. Urine samples from 17 naive OAB women were collected at baseline and 3 months after life-style counselling. NGF and BDNF content was determined by ELISA and normalized against creatinine (Cr) concentration. For each OAB patient the severity of symptoms was accessed using Indevus Urgency Severity Scale (IUSS).
RESULTS: In healthy volunteers, urinary NGF and BDNF levels were constantly low, despite the time of urine collection (morning, afternoon and night). No differences were found between genders.
BDNF/Cr ratio was significantly higher at baseline in OAB patients compared to healthy volunteers (9801775 vs 110160, p0.01).
NGF/Cr was also higher in OAB patients (423526 vs 188290,
p0.072). Wet OAB patients had higher urinary BDNF levels
(17952874 vs 536542). No such finding was found with NGF.
Life-style counselling decreased urinary BDNF/Cr (980 1775
vs 399488, p0.078) and NGF/Cr (423526 vs 231275, p0.179).
However, at this time point, BDNF/Cr levels were still significantly higher than in healthy volunteers. A significant correlation was only found between BDNF/Cr ratio and IUSS score variations (r0.684, p0.01).
CONCLUSIONS: As far as we know, this is the first comprehensive study of urinary NGF and BDNF in healthy volunteers. In this group, NGF and BDNF levels had no circadian rhythm and were persistently low, irrespective of gender. In OAB patients, urinary BDNF/Cr and NGF/Cr were high and decreased after a 3-month non-pharmacological intervention. Only BDNF/Cr had a significant correlation with IUSS score variation. The differences observed between OAB patients and controls clearly point that urinary neutrophins can be
potential biomarkers of OAB syndrome.
Idioma:
Inglês
Tipo (Avaliação Docente):
Científica