Effects of Soy Protein Isolate Feeding on Severe Kidney Damage in DOCA Salt-Treated Obese Zucker Rats

Abstract

This study assessed the effects of soy protein isolate (SPI) on severe kidney damage in deoxycorticosterone acetate (DOCA) salt-treated obese Zucker rats. These rats underwent heminephrectomy and were fed either casein or SPI diet for 12 weeks. From weeks 8 to 10 of the experiment, kidney damage was induced by biweekly injection of 25 mg/kg DOCA and administration of 0.5% NaCl (w/v) ad libitum. Urinary protein and N-acetyl-β-d-glucosaminidase excretions of SPI rats were much lower than those of casein rats at weeks 1 (p < 0.01) and 2 (p < 0.05) after DOCA treatment. Abnormal mineral excretions induced by DOCA treatment in casein rats were hardly detected in SPI rats. Severe atrophy of tubular epithelium and some flattened/detached renal tubules were also observed in casein rats, but not in SPI rats. These results indicate that consecutive treatment of SPI protects against renal dysfunction, particularly tubulointerstitial nephritis, in DOCA salt-treated obese Zucker rats.

Renal cyclooxygenase and lipoxygenase products are altered in polycystic kidneys and by dietary soy protein and fish oil treatment in the Han:SPRD‐Cy rat

“…Dietary soy protein (SP) consistently displays a protective effect in experimental models of renal cyst disease [9,[19][20][21][22][23], as well as other renal diseases [24,25]. It is different from FO in that dietary SP only has minor effects on tissue fatty acid compositions, but it also may mediate its beneficial effects on renal diseases via alterations in eicosanoid production, at least in part.…”

Effects and Clinical Significances of Orally Supplementary Soybean β-Conglycinin in Subjects with Dyslipidemia and Renal Dysfunction

“…Soy protein has been reported to suppress the progression of diabetic nephropathy [20][21][22] and have beneficial effect for correcting LDL-C [3,23]. β-conglycinin is a major component of soy protein, has been reported to decrease serum triglyceride, LDL levels and visceral fat [1][2][3][4].…”

Soybean and Other Legume Proteins Exhibit Beneficial Physiological Effects on Metabolic Syndrome and Inflammatory-Related Disorders

“…In the Atherosclerosis Risk in Communities [ARIC] study of ~12,000 US participants with 23 years of follow-up, consumption of legumes was significantly associated with lower risks of CKD, with an HR of 0.83 [95% CI, 0.72; 0.95] for high versus low intakes [36]. Soy protein, which is representative of legumes, has been reported to suppress the progression of DN [37,38]. The effects of soy protein on DN/CKD in clinical trials are summarized in Table 3 [39][40][41][42][43].…”