Evaluation of Renin Angiotensin System (RAS) in Renal Transplant Patients

Abstract

Kidney transplantation is a surgical process that involves swapping the diseased kidney for a healthy kidney. In Brazil, about 5500 transplants per year are performed. After the transplantation process, the patients started to use immunosuppression therapy for acute rejection prophylaxis. There are two immunosuppressants that are most commonly used, Everolimus, Tacrolimus and Sodium Mycophenolate. Current immunosuppressive regimens are effective in preventing acute rejection but have several adverse events. Among them, hypertension and diabetes probably occurred due to an imbalance in RAS. In view of the above observations, the objective of this study was to verify the expression of the proteins and peptides of the RAS, in order to understand if there were changes in the modulation of the same. Two groups of patients, diabetics (n=10) and non‐diabetics (n=10), all with the underlying disease, hypertension, were analyzed. For this purpose, patients were collected at different times after transplantation: seven days (D7), fourteen days (D14), one month (M1), two months (M2), three months (M3), four months M4), five months (M5) and six months (M6). Patient plasma was prepared separately for albumin removal, and subjected to HiScreen Blue FF (GE Healthcare) (1 × 4.7 ml) affinity column chromatography coupled to Akta FPLC system and equilibrated with 50 mM Monopotassium Phosphate buffer, pH 7.0, under flow rate of 1.0 mL/min. The purification of the samples analyzed for one patient is in the table above.Purified plasma in different times was submitted to western blotting in order to demonstrate the expression of angiotensin converting enzyme (ACE). In the table above, we can see that the ACE expression increased gradually in the times of D7 to M6, coinciding with the detection of more pronounced hypertension in this patient (M6). This pilot study suggests that the healthy kidney is likely to be physiologically modified as a result of medications received by the patient, immunological modulations, leading to hypertension and that RAS is involved in this profile.Support or Funding InformationCAPES and CNPq Purification Sample (days) D7 D14 M1 M2 M3 M4 M5 M6 Times (x) 15,65 12,40 15,40 12,87 14,32 16,55 10,72 17,30 Protein Expression (Arbitrary Units) Expression ACE 190 0,933 1,119 1,390 2,483 2,630 2,517 2,545 4,755 90 0,846 1,200 1,183 1,587 1,839 2,167 2,310 3,158 65 1,625 1,376 1,246 1,420 1,702 1,775 1,687 2,047 This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.