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Background: Physical exercise (PE) can regulate inflammation, cardiovascular health, sarcopenia, anaemia, and bone health in the chronic kidney disease (CKD) population. Experimental and clinical studies both help us better understand the mechanisms that underlie the beneficial effects of the exercise, especially in renal anaemia and CKD-mineral bone disorders (CKD-MBDs). Here, we summarize this evidence, exploring the biological pathways involved, locally released substances, and crosstalk between tissues, but also the shortcomings of current knowledge. Summary: Anaemia: Both in healthy and CKD subjects, PE may mimic hypoxia, inhibiting PHDs; so hydroxylate HIF-α subunits may be translocated into the nucleus, resulting in dimerization of HIF-1α and HIF-1β, recruitment of p300 and CBP, and ultimately, binding to HREs at target genes to cause activation. However, in CKD subjects acute PE causes higher levels of lactate, leading to iron restriction by upregulating hepatic hepcidin expression, while chronic PE allows an increased lactate clearance and HIF-α and VEGFα levels, stimulating both erythropoiesis and angiogenesis. CKD-MBD: PE may improve bone health decreasing bone resorption and increasing bone formation throughout at least three main pathways: (a) increasing osteoprotegerin and decreasing RANKL system; (b) decreasing cytokine levels; and (c) stimulating production of myokines and adipokines. Key Messages: Future research needs to be defined to develop evidence-based exercise guidance to provide optimal benefit for CKD using exercise interventions as adjuvant therapy for CKD-related complications such as anaemia and CKD-MBD. [ABSTRACT FROM AUTHOR]

Hyperammonemia in urea cycle disorders: role of the nephrologist Severe hyperammoniemia denotes a clinical condition associated with high blood ammonia levels and uncertain prognosis. The presentation can vary with the age of the patent and the magnitude of the increase in blood ammonia levels. Persistent hyperammonemia, if not treated rapidly, may cause irreversible neuronal damage. The aim of therapy should be to normalize blood ammonia levels. Recent experience has provided treatment guidelines that include minimizing endogenous ammonia production and protein catabolism, restricting nitrogen intake, administering substrates of the urea cycle, administering compounds that facilitate the removal of ammonia through alternative pathways, and, in severe cases, dialysis therapy. Hemodialysis is the most effective treatment for rapidly reducing blood ammonia levels. Continuous hemofiltraton and peritoneal dialysis are also effective modalities to reduce blood ammonia levels. An improved understanding of the metabolism of ammonia and clinical consequences of hyperammonemia will assist the nephrologist in providing optimal care for this high-risk patent population. [ABSTRACT FROM AUTHOR]