Date Published: March 2, 2018
Publisher: Public Library of Science
Author(s): Bruna Bellincanta Nicoletto, Elis Forcellini Pedrollo, Larissa Salomoni Carpes, Natália Gomes Coloretti, Thaiana Cirino Krolikowski, Gabriela Corrêa Souza, Luiz Felipe Santos Gonçalves, Roberto Ceratti Manfro, Luis Henrique Canani, Abelardo I Aguilera.
The adipokine progranulin has metabolic proprieties, playing a role in obesity and insulin resistance. Its levels seems to be dependent of renal function, since higher progranulin concentration is observed in patients with end-stage kidney disease. However, the effect of kidney transplantation on progranulin remains unknown.
To assess the serum progranulin levels in kidney transplant recipients before and after kidney transplantation.
Forty-six prospective kidney transplant recipients were included in this longitudinal study. They were evaluated before transplantation and at three and twelve months after transplantation. Clinical, anthropometric and laboratorial measurements were assessed. Progranulin was determined with enzyme-linked immunosorbent assays.
Serum progranulin significantly decreased in the early period after transplantation (from 72.78 ± 2.86 ng/mL before transplantation to 40.65 ± 1.49 ng/mL at three months; p<0.01) and increased at one year (53.15 ± 2.55 ng/mL; p<0.01 vs. three months), remaining significantly lower than before transplantation (p<0.01) (pover time<0.01). At one year after transplantation, there was a significant increase in body mass index, trunk fat and waist circumference compared to immediate period after transplantation. Progranulin was associated with waist circumference and fasting plasma glucose after adjusted for age, gender, study period, glomerular filtration rate, interleukin-6, high sensitivity C reactive protein and adiponectin. Progranulin serum levels are increased before transplantation and a reduction is observed in the early period after transplantation, possibly attributed to an improvement in renal function. At one year after transplantation, an increment in progranulin is observed, seems to be independent of glomerular filtration, and remained significantly lower than before transplantation.
Progranulin (PGRN), also known as proepithelin, granulin/epithelin precursor, or PC cell–derived growth factor, has emerged as a protein with growth factor-like properties, being involved in tissue remodeling, tumorigenesis and neurodegenerative diseases [1–4]. More recently, it has been associated with obesity and insulin resistance [5, 6]. PGRN is expressed in epithelial cells, immune cells, neurons and also in adipocytes , emerging as a novel adipokine with a function in glucose and insulin metabolisms [5, 6]. PGRN plays a role in adipose tissue, recruiting monocytes  and promoting interleukin-6 (IL-6) expression , which favors inflammation and insulin resistance. Previous studies have demonstrate that serum PGRN is increased in obesity and type 2 diabetes mellitus (T2DM) [8–10].
In this longitudinal study, it was possible to demonstrate changes in PGRN serum concentration overtime after kidney transplantation. In patients with end-stage renal disease, PGRN is elevated, and it decreases upon eGFR improvement in the early period after kidney transplantation. At one year, an increment in PGRN is observed, seems to be independent of eGFR, and remained significantly lower than before transplantation.