Abstract: BACKGROUND: The expression of long chain non-coding RNA PGM5-AS1 (lnc RNA PGM5-AS1) is reduced in peripheral blood of patients with acute immune rejection after renal transplantation. The effect of its expression on human glomerular endothelial cell (HRGEC) survival and macrophage chemotaxis remains to be studied.
OBJECTIVE: To investigate the expression of lnc RNA PGM5-AS1 in serum of patients with acute rejection of renal transplantation and non-acute rejection patients and its effect on proliferation, cell cycle, apoptosis and macrophages chemotropism of HRGECs.
METHODS: Forty-six patients with renal transplantation were divided into acute rejection group (n=17) and non-acute rejection group (n=29) according to whether or not acute rejection occurred within 1 month after operation. Peripheral blood sample was drawn from each patient at 1 day before operation, 1, 2, 3, and 4 weeks after operation. qRT-PCR was used to detect the expression of PGM5-AS1 in serum of patients with or without acute rejection. si-control and si-PGM5-AS1 were transfected into glomerular endothelial cells, and the expression of PGM5-AS1 in the transfected cells was detected by qPCR. MTT was used to detect cell proliferation, flow cytometry was applied to detect apoptosis and cell cycle, ELISA was adopted to detect cellular inflammatory factor secretion, and Transwell was used to detect chemotaxis of macrophages. Approval for this study was obtained from the Ethics Committee of Zhengzhou People’s Hospital, and all patients signed informed consent prior to the participation in the trial.
RESULTS AND CONCLUSION: Compared with non-acute rejection patients, patients with acute rejection to renal transplantation had significantly lower PGM5-AS1 expression in serum at 1, 2, 3, and 4 weeks after transplantation (P < 0.05). After PGM5-AS1 silencing, the expression of GM5-AS1 in HRGEC cells was significantly lower than that in the si-control group and normal control group (F=379.658, P < 0.05). MTT results showed that PGM5-AS1 silencing significantly inhibited HRGEC cell proliferation (P < 0.05). Flow cytometry results showed that PGM5-AS1 silencing induced HRGEC cell arrest in G0/G1 phase and increased apoptosis (P < 0.05). ELISA results showed that PGM5-AS1 silencing inhibited interleukin-13 expression and increased interleukin-6, interferon-γ and tumor necrosis factor-α expression (P < 0.05). Transwell results indicated that HRGEC cells silenced by PGM5-AS1 significantly increased the chemotaxis of macrophages (P < 0.05). All these findings indicate that PGM5-AS1 is lowly expressed in serum of patients with acute rejection of renal transplantation, and inhibition of PGM5-AS1 can promote HRGEC cell damage, which can be used as a peripheral blood diagnostic marker for early acute rejection, and may be a molecular target for the treatment of acute rejection.

Key words: kidney, renal transplantation, acute rejection, long non-coding RNA, glomerular endothelial cells, cell cycle, target, marker