Effect of selenium-deficient diet in experimental glomerular disease

Area of Science:

• Nephrology
• Nutritional Science
• Biochemistry

Background:

• Glomerular diseases, including minimal change disease and membranous nephropathy, represent significant causes of kidney damage.
• Selenium is an essential trace element crucial for antioxidant defense, primarily through glutathione peroxidase enzymes.

Purpose of the Study:

• To investigate the impact of a selenium-deficient diet on two distinct experimental models of glomerular injury: puromycin aminonucleoside (PAN)-induced nephrotic syndrome and passive Heymann nephritis.
• To elucidate the role of selenium-dependent glutathione peroxidase in the pathogenesis of these kidney diseases.

Main Methods:

• Two experimental models of glomerular disease were utilized in Sprague-Dawley rats: PAN-induced nephrotic syndrome and passive Heymann nephritis.
• Rats were fed either a selenium-deficient or a selenium-replete diet for six weeks.
• Levels of selenium-dependent glutathione peroxidase, superoxide dismutase, and catalase activities were measured in liver, kidney cortex, and glomeruli.
• Proteinuria was quantified, and histological examination and antibody deposition were assessed in the kidney.

Main Results:

• Selenium deficiency significantly reduced glutathione peroxidase activity in the liver, kidney cortex, and glomeruli, without affecting superoxide dismutase or catalase.
• Rats on a selenium-deficient diet exhibited significantly higher proteinuria in both the PAN-induced nephrotic syndrome and passive Heymann nephritis models compared to selenium-replete controls.
• No significant differences in histological findings or antibody deposition were observed between the dietary groups in either model.

Conclusions:

• Selenium deficiency exacerbates proteinuria in experimental models of glomerular injury, likely due to the marked reduction in glutathione peroxidase activity.
• Glutathione peroxidase plays a critical role in protecting against glomerular injury, and its deficiency compromises renal function in these models.
• These findings underscore the importance of adequate selenium intake for maintaining kidney health and preventing or mitigating glomerular damage.