Chronic dietary supplementation with kynurenic acid, a neuroactive metabolite of tryptophan, decreased body weight without negative influence on densitometry and mandibular bone biomechanical endurance in young rats

Autoři: Ewa Tomaszewska aff001;  Siemowit Muszyński aff002;  Damian Kuc aff003;  Piotr Dobrowolski aff004;  Krzysztof Lamorski aff005;  Katarzyna Smolińska aff006;  Janine Donaldson aff007;  Izabela Świetlicka aff002;  Maria Mielnik-Błaszczak aff003;  Piotr Paluszkiewicz aff008;  Jolanta Parada-Turska aff009
Působiště autorů: Department of Animal Physiology, University of Life Sciences in Lublin, Lublin, Poland aff001;  Department of Biophysics, University of Life Sciences in Lublin, Lublin, Poland aff002;  Department of Developmental Age Stomatology, Chair of Developmental Age Stomatology, Medical University of Lublin, Lublin, Poland aff003;  Department of Comparative Anatomy and Anthropology, Maria Curie-Sklodowska University, Lublin, Poland aff004;  Bohdan Dobrzański Institute of Agrophysics of the Polish Academy of Sciences, Lublin, Poland aff005;  Department of Surgery and Surgical Nursing, Medical University of Lublin, Lublin, Poland aff006;  School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Parktown, South Africa aff007;  Department of General, Oncological and Metabolic Surgery, Institute of Haematology and Transfusion Medicine, Warszawa, Poland aff008;  Department of Rheumatology and Connective Tissue Diseases, Medical University of Lublin, Lublin, Poland aff009
Vyšlo v časopise: PLoS ONE 14(12)
Kategorie: Research Article


Kynurenic acid (KYNA) is a neuroactive metabolite of tryptophan. KYNA naturally occurs in breast milk and its content increases with lactation, indicating the role of neonatal nutrition in general growth with long-term health effects. KYNA is also an antagonist of ionotropic glutamate receptors expressed in bone cells. The aim of this study was to establish the effects of chronic KYNA supplementation on bone homeostasis in young rats, using mandible as a model bone. Female and male newborn Wistar rats were divided into control and KYNA-administered groups until 60 days of age (25x101 mg/L or 25x102 mg/L in drinking water). Hemimandibles were subjected to densitometry, computed tomography analysis and mechanical testing. Rats supplemented with KYNA at both doses showed a decrease in body weight. There were no effects of KYNA administration and mandible histomorphometry. In males, a significant quadratic effect (P < 0.001) was observed in the densitometry of the hemimandible, where BMD increased in the group supplemented with 2.5x101 mg/L of KYNA. Analysis of mechanical tests data showed that when fracture forces were corrected for bone geometry and rats body weight the improvement of bone material properties was observed in male and female rats supplemented with lower dose of KYNA. This study showed that chronic supplementation with KYNA may limit weight gain in the young, without adversely affecting the development of the skeleton.

Klíčová slova:

Body weight – Bone and joint mechanics – Bone fracture – Glutamate – Mandible – Tryptophan – Water resources


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