The molecular structure of beta-alanine is resistant to sterilising doses of gamma radiation

Author(s)

Goncalves, Livia de Souza ^[1] ; Franchi, Mariana ^[1] ; Mathor, Monica B. ^[2] ; Lugao, Ademar B. ^[2] ; Carvalho, Victor H. ^[3] ; Medeiros, Marisa H. G. ^[3] ; Artioli, Guilherme Giannini ^[1] ; Varca, Gustavo H. C. ^[2]

Affiliation

^[1] Univ Sao Paulo, Fac Med FMUSP, Rheumatol Div, Appl Physiol & Nutr Res Grp, Sao Paulo, SP - Brazil

^[2] IPEN CNEN SP, Inst Pesquisas Energet & Nucl, Sao Paulo, SP - Brazil

^[3] Univ Sao Paulo, Inst Quim, Dept Bioquim, Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: PLoS One; v. 14, n. 1 JAN 15 2019.
• Web of Science Citations: 0

Abstract

beta-alanine is the rate-limiting point for the endogenous synthesis of carnosine in skeletal muscle. Carnosine has a wide range of implications for health, normal function and exercise performance. Whilst the physiological relevance of carnosine to different tissues remains enigmatic, beta-alanine administration is a useful strategy to investigate the physiological roles of carnosine in humans. Intravenous administration of beta-alanine is an interesting approach to study carnosine metabolism. However, sterilisation is mandatory due to the nature of the administration route. We evaluated whether sterilising doses of gamma radiation damages the molecular structure and leads to the loss of functional characteristics of beta-alanine. Pure beta-alanine was sterilised by gamma radiation in sealed glass vials using a Co-60 multipurpose irradiator at a dose rate of 8.5 kGy.hour(-1) totalising 10, 20, 25 30 and 40 kGy. The molecular integrity was assessed by X-ray Diffraction and changes in content were determined by High Performance Liquid Chromatography (UV-HPLC) and Triple Quadrupole Mass Spectrometer (HPLC/MS-MS). Sterility assurance was evaluated by inoculation assay. To examine whether functional properties were preserved, beta-alanine was infused in one participant, who rated the level of paraesthesia on the skin using a 0-3 scale. Urinary beta-alanine was quantified before and 24-h following beta-alanine infusion using HPLC-ESI+-MS/MS. Irradiation resulted in no change in the crystal structure of beta-alanine, no degradation, and no new peaks were identified in the dose range assayed. The inoculation assay showed the absence of viable microorganisms in all beta-alanine samples, including those that did not undergo irradiation. Intravenous infusion of beta-alanine resulted in paraesthesia and it detected in the urine as per normal. We conclude that gamma radiation is a suitable technique for the sterilisation of beta-alanine. It does not lead to degradation, damage to the beta-alanine structure, content or loss of function within the evaluated irradiation conditions. (AU)

• FAPESP's process: 14/11948-8 - Life without carnosine: development and characterization of a KO rat model for studying the physiological role of carnosine and its implications to physical exercise and muscle metabolism
• Grantee: Guilherme Giannini Artioli
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 13/07937-8 - Redoxome - Redox Processes in Biomedicine
• Grantee: Ohara Augusto
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 15/13979-0 - Nanostructured radiation-induced protein based systems as carriers for chemoterapeuticals
• Grantee: Gustavo Henrique Costa Varca
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/22686-7 - Effect of beta-alanine supplementation on muscle carnosine and taurine concentrations during six months
• Grantee: Mariana Franchi
• Support Opportunities: Scholarships in Brazil - Scientific Initiation