Biomarkers of renal function in preterm neonates at 72 h and 3 weeks of life

Abstract Objective: Serum levels of creatinine in neonates are quite variable and suffer interference from the immature kidney and maternal creatinine concentration. The aim of this study was to measure novel biomarkers of glomerular and tubular function in healthy preterm neonates at 72 h and 3 weeks of life. Methods: Urine samples were collected in 40 preterm neonates with 28-34 incomplete weeks of gestational age. None of the participants had comorbidities, malformations and infections. The samples were collected at 72 h of life and at 3 weeks after birth. Measurements of Calbindin, Collagen IV, FABP1, αGST, IP-10, KIM-1, Osteoactivin, Renin, TFF-3, TIMP-1, α-1-Microglobulin, Albumin, Clusterin, Cystatin C, EGF, Lipocalin-2/NGAL and Osteopontin were performed using panels 1 and 2 of multiplex kits of kidney injury. Data were analyzed using the software GraphPad Prism version 6.0. Results: The preterm neonates included 55% of males with gestational age of 30 ± 1 weeks. The most frequent maternal condition associated with preterm birth was preeclampsia (80%). Molecules related to glomerular function showed a significant increase in the concentrations obtained at 3 weeks of life compared to 72 h of life. Markers related to tubular injury (KIM-1 and NGAL) also showed an increase. On the other hand, cystatin C did not change. Conclusion: The elevation of molecules related to glomerular function indicates an increase of glomerular filtration rate from 72 h up until 3 weeks of life, which was not clearly detected with the measurement of cystatin C.

Biomarkers of renal function in preterm neonates at 72h and 3weeks of life.

OBJECTIVE: Serum levels of creatinine in neonates are quite variable and suffer interference from the immature kidney and maternal creatinine concentration. The aim of this study was to measure novel biomarkers of glomerular and tubular function in healthy preterm neonates at 72h and 3 weeks of life. METHODS: Urine samples were collected in 40 preterm neonates with 28-34 incomplete weeks of gestational age. None of the participants had comorbidities, malformations and infections. The samples were collected at 72h of life and at 3 weeks after birth. Measurements of Calbindin, Collagen IV, FABP1, αGST, IP-10, KIM-1, Osteoactivin, Renin, TFF-3, TIMP-1, α-1-Microglobulin, Albumin, Clusterin, Cystatin C, EGF, Lipocalin-2/NGAL and Osteopontin were performed using panels 1 and 2 of multiplex kits of kidney injury. Data were analyzed using the software GraphPad Prism version 6.0. RESULTS: The preterm neonates included 55% of males with gestational age of 30±1 weeks. The most frequent maternal condition associated with preterm birth was preeclampsia (80%). Molecules related to glomerular function showed a significant increase in the concentrations obtained at 3 weeks of life compared to 72h of life. Markers related to tubular injury (KIM-1 and NGAL) also showed an increase. On the other hand, cystatin C did not change. CONCLUSION: The elevation of molecules related to glomerular function indicates an increase of glomerular filtration rate from 72h up until 3 weeks of life, which was not clearly detected with the measurement of cystatin C.

Renin angiotensin system molecules and nitric oxide local interactions in the adrenal gland of Trypanosoma cruzi infected rats.

Chagas disease (CD) is a tropical zoonosis caused by the protozoan Trypanosoma cruzi. Severe autonomic dysfunction like reduced cardiac catecholamine-containing or acetylcholinesterase-positive innervation have been reported in CD. Renin-angiotensin system (RAS) seems to participate in the regulation of adrenal catecholamine secretion by adrenal medullary chromaffin cells, which might be dependent of nitric oxide (NO) pathways. To investigate the levels of RAS components in the adrenal gland during the acute infection with Y strain T. cruzi and in response to acute administration of an inhibitor of the enzyme NO synthase, L-NAME. Male Holtzman rats were inoculated intraperitoneally with Y strain T. cruzi and received L-NAME or tap water from one day before the infection until 13 or 17 days post-inoculation (dpi). The concentration of RAS molecules in the adrenal tissue was evaluated by ELISA immunoassay. Angiotensin converting enzyme 1 (ACE1) levels were significantly lower at 17 dpi when compared to 13 dpi. No significant differences were found compared with baseline, and no changes were detected in adrenal tissue levels of angiotensin converting enzyme 2 (ACE2), angiotensin II, or angiotensin-(1-7). Moreover, the treatment with L-NAME did not influence the levels of RAS components in adrenal tissue during the course of T. cruzi infection. We provided the first evidence that levels of RAS molecules change in the adrenal gland during acute phase of T. cruzi infection. Future studies are necessary to fully address the role of NO in RAS-associated adrenal gland function in CD.