A High Phosphorus Diet Impairs Testicular Function and Spermatogenesis in Male Mice with Chronic Kidney Disease

Abstract

Hyperphosphatemia is a serious complication in chronic kidney disease (CKD) that occurs due to insufficient excretion of phosphorus during failure of renal function. Both CKD and an excessive phosphorus intake have been reported to increase oxidative stress and result in poor male fertility, but little is known about the reproductive function of the CKD under a poorly controlled phosphate intake. Eight-week-old C57BL/6 mice (n = 66) were randomly divided into four groups: a sham operation group received a chow diet as control (SC group, n = 14), CKD-induced mice received a chow diet (CKDC group, n = 16), control mice received a high phosphorus (HP) diet (SP group, n = 16), and CKD-induced mice received a HP diet (CKDP group, n = 20). CKD was induced by performing a 5/6 nephrectomy. The chow diet contained 0.6% phosphorus, while the HP diet contained 2% phosphorus. Impaired testicular function and semen quality found in the CKD model may result from increased oxidative stress, causing apoptosis and inflammation. The HP diet aggravated the negative effects of testicular damage in the CKD-induced mice.

Extracellular Inorganic Phosphate-Induced Release of Reactive Oxygen Species: Roles in Physiological Processes and Disease Development

“…Normal diet (0.3% Pi) compared to high Pi diet (1.2%) [60]. Normal diet (0.6% Pi) compared to high Pi diet (2.0%) [59].…”

“…The study also analysed a group of mice fed high phosphorus that drank a potent ROS scavenger, N-acetylcysteine (NAC), at 1.5 mg/weight/day (Figure 4 and Table 5) [60]. A high Pi diet, chronic kidney disease (CKD), or both in WKY rats [60] or C57BL/6 mice [59] increases serum Pi, oxidative stress, and apoptosis in the testicles. Testicular apoptosis induced by oxidative stress promotes a decrease in testicular weight, sperm count, sperm motilities, and seminiferous tubule diameter [59,60].…”

“…A high Pi diet, chronic kidney disease (CKD), or both in WKY rats [60] or C57BL/6 mice [59] increases serum Pi, oxidative stress, and apoptosis in the testicles. Testicular apoptosis induced by oxidative stress promotes a decrease in testicular weight, sperm count, sperm motilities, and seminiferous tubule diameter [59,60]. Nevertheless, this effect is restored by supplementation with a potent oxidative species scavenger, N-acetylcysteine (NAC) [59].…”

“…Testicular apoptosis induced by oxidative stress promotes a decrease in testicular weight, sperm count, sperm motilities, and seminiferous tubule diameter [59,60]. Nevertheless, this effect is restored by supplementation with a potent oxidative species scavenger, N-acetylcysteine (NAC) [59].…”

“…Another study sought to relate the influence of high Pi on male reproductive function in C57BL/6 mice with CKD induced after nephrectomy [59]. Therefore, the mice were randomly divided into four groups: (1) normal food (0.6% phosphorus); (2) food with high Pi (2% phosphorus); (3) CKD induced with regular feeding; and (4) CKD induced with high Pi feeding.…”