Green Peas Protein Hydrolyzed by Bromelain in Simple Procedure to Improve Kidney Function in Cisplatin-induced Rats

Context: Chronic kidney disease (CKD) can lead to terminal kidney failure. Previous study has shown that protein hydrolysate in yellow peas (Pisum sativum L.) can be used as a natural remedy for CKD. 
Aims: To obtain hydrolysate protein that is most effective in improving kidney function of cisplatin (CP)‑induced Wistar rats, based on urea, creatinine, atrial natriuretic peptide (ANP), cyclooxygenase‑1 (COX‑1), and renin levels of CP‑induced nephrotoxicity Wistar rats. 
Materials and Methods: Methods of Kjeldahl, Bradford, Kunitz, and sodium dodecyl sulfate‑polyacrylamide gel electrophoresis were used to determine the content of the eight types of protein hydrolysates. In in vivo experiment, the samples were administered to CP‑induced nephrotoxicity Wistar rats, with urea, creatinine, ANP, COX‑1, and renin as parameters. 
Results: Total neutrase activity was 40.65 U/mg, and bromelain was 35.77 U/mg. Total specific activities of both enzymes were almost identical. Protein hydrolyzed using bromelain had small fractions (<14.4 kDa). On the 30th day of treatment, urea and creatinine levels of all groups of treatment were significantly different from CP control (P < 0.01). The lowest level was shown by the group which was treated with bromelain‑hydrolyzed green pea protein. Among ANP, COX‑1, and renin measurements, only the result of COX‑1 showed the promising result. 
Conclusions: Green peas protein hydrolysate hydrolyzed by bromelain are suggested as the most effective in improving kidney function based on urea, creatinine, and COX-1 levels of CP-induced nephrotoxicity Wistar rats.