Objective To observe the effect of low protein diet supplemented with ketoacid on the protection of remnant kidney and the inhibition of inflammation infiltration in 5/6 nephrectomized rats. Methods Thirty male Sprague-Dawley rats were randomly assigned to following 3 groups and given different diets: low protein supplemented with ketoacid group(4% casein protein+2%ketoacid), low protein group(6% casein protein) and high protein group (20% casein protein). Ten SD rats were uses as sham-operation group(20% casein protein). The former three groups were subjected to 5/6 nephrectomy. Urine and blood samples were collected before operation and 4, 8 and 12 weeks after operation. All rats were killed after 12 weeks and pathologic changes of kidney tissue were investigated by microscope. Immunohistochemistry was also employed to investigate the expression of MCP-1, RANTES, ED-1 within the residual kidney. Results Scr and BUN of operated rats increased gradually. Compared with high protein group and low protein group, Scr and BUN of low protein supplemented with ketoacid group were significantly lower[Scr (125.44±5.50) vs (172.00±9.54), (135.22±9.54) μmol/L, P<0.01]. The urinary albumin excretion (UAE) increased significantly at the 4th week and reached the peak at the 12th week. The UAE (mg/24 h) of low protein supplemented ketoacid group (28.36±3.69)was markedly lower than that of high protein group(92.32±34.06) and low protein group(46.62±6.19). Compared with the latter two groups, pathological lesion of low protein supplemented with ketoacid group was obviously improved (glomerular pathological score 0.38±0.13 vs 0.84±0.28, 0.49±0.11, P<0.01). The expression levels of MCP-1, RANTES, ED-1 in operation groups were significantly higher than those in sham-operation group, and above expression levels in low protein supplemented with ketoacid group were the lowest among three operation groups (positive ED-1 cell 3.59±0.78 vs 13.33±1.20, 6.50±0.99, P<0.01). Conclusion Low protein diet supplemented with ketoacid can attenuate pathological lesion of residual kidney through certain mechanisms such as inhibition of inflammatory infiltration.
YE Han-yang;YUAN Wei-jie;ZHANG Zhi-qiang;BIAN Qi;YU Jian-ping;FU Peng;MEI Xiao-bin;GUO Yun-shan;CUI Ruo-lan.
Study on the renoprotective effect of low protein diet supplemented with ketoacid in 5/6 nephrectomized rats[J]. Chinese Journal of Nephrology, 2007, 23(6): 394-399.