{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T14:50:11Z","timestamp":1785855011084,"version":"3.56.0"},"reference-count":32,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,6,30]],"date-time":"2022-06-30T00:00:00Z","timestamp":1656547200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Pisa (Italy)","award":["PRA_2020_69"],"award-info":[{"award-number":["PRA_2020_69"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Abnormalities of serum amino acid profile, mostly characterized by a reduction in essential amino acids (EAAs) and an increase in non-essential amino acids (NEAAs), have been documented in human chronic kidney diseases (CKD). Amino acid disorders have been associated with CKD complications, such as metabolic acidosis and malnutrition. The aim of the present study was to evaluate EAAs and NEAAs in dogs affected by CKD at different IRIS stages, with particular reference to calcium\u2013phosphate abnormalities, metabolic acidosis, and protein-energy wasting syndrome (PEW). Serum EAAs (L-histidine, L-isoleucine, L-leucine, L-lysine, methionine, L-phenylalanine, L-threonine, tryptophan, L-valine, and L-arginine) and serum NEAAs (L-alanine, L-aspartic acid, L-cysteine, L-glutamic acid, glycine, proline, L-serine, and L-tyrosine) were analyzed with HPLC in a group of dogs with CKD (n = 62), and in a group of healthy dogs (n = 25). CKD dogs showed significantly lower serum levels of histidine (p &lt; 0.000), isoleucine (p &lt; 0.000), tryptophan (p &lt; 0.000), alanine (p = 0.013), cysteine (p &lt; 0.000), and serine (p = 0.002), and significantly higher levels of proline (p &lt; 0.000), leucine (p = 0.001), lysine (p &lt; 0.000), valine (p &lt; 0.000), arginine (p = 0.002), glutamic acid (p = 0.002), and glycine (p = 0.010) compared to healthy dogs. Dogs with abnormal calcium x phosphate values showed significantly higher levels of cysteine (p = 0.003), and lower levels of tryptophan (p = 0.025) compared to CKD dogs with normal CaxP. Dogs with metabolic acidosis showed significantly higher levels of phenylalanine (p = 0.035) and leucine (p = 0.034) compared to CKD dogs without metabolic acidosis. Dogs with PEW showed significantly lower levels for most of amino acids. In PEW dogs, the median distribution of both EAAs (p = 0.000) and NEAAs (p = 0.001) was significantly lower. The serum pattern of both EAAs and NEAAs was significantly different in CKD dogs compared to healthy dogs, although no association with the progression of the IRIS stage was found.<\/jats:p>","DOI":"10.3390\/vetsci9070331","type":"journal-article","created":{"date-parts":[[2022,7,1]],"date-time":"2022-07-01T01:40:36Z","timestamp":1656639636000},"page":"331","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Essential and Non-Essential Amino Acids in Dogs at Different Stages of Chronic Kidney Disease"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3595-6067","authenticated-orcid":false,"given":"Ilaria","family":"Lippi","sequence":"first","affiliation":[{"name":"Dipartimento di Scienze Veterinarie, Universit\u00e0 di Pisa, 56122 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4703-7559","authenticated-orcid":false,"given":"Francesca","family":"Perondi","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Veterinarie, Universit\u00e0 di Pisa, 56122 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9336-5150","authenticated-orcid":false,"given":"Alessio","family":"Pierini","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Veterinarie, Universit\u00e0 di Pisa, 56122 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2702-3259","authenticated-orcid":false,"given":"Francesco","family":"Bartoli","sequence":"additional","affiliation":[{"name":"Dipartimento di Ricerca Traslazionale e delle Nuove Tecnologie in Medicina e Chirurgia, 56120 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8612-5573","authenticated-orcid":false,"given":"Eleonora","family":"Gori","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Veterinarie, Universit\u00e0 di Pisa, 56122 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7127-4680","authenticated-orcid":false,"given":"Chiara","family":"Mariti","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Veterinarie, Universit\u00e0 di Pisa, 56122 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6099-6223","authenticated-orcid":false,"given":"Veronica","family":"Marchetti","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Veterinarie, Universit\u00e0 di Pisa, 56122 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,30]]},"reference":[{"key":"ref_1","first-page":"1202","article-title":"Branched chain amino acid profile in early chronic kidney disease","volume":"23","author":"Kumar","year":"2012","journal-title":"Saudi J. 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