• PMID: 15820478
• Gene Name: HEXB
• Condition: Azoospermia
• Association: It was not possible to confirm that total Hex activity in seminal plasma, or even of its isoenzymes Hex A and Hex B, is a suitable biochemical marker of azoospermia (efficiency< or =67%). The thermodynamic procedure described may be a useful alternative f
• Sex: Male
• Infertility type: Male infertility
• Associated genes: Hex A, Hex B
• Other associated phenotypes: Azoospermia

Thermodynamic study of beta-N-acetylhexosaminidase enzyme heterogeneity in human seminal plasma

Casal JA, Vizcaíno L, Garcia-Devesa J, Tutor JC.

BACKGROUND: It has been suggested that the activity of beta-N-acetylhexosaminidase (Hex) in seminal plasma may be used as a biochemical marker of azoospermia. The purpose of our study was to evaluate this hypothesis using a thermodynamic procedure developed to determine total Hex activity and that of its isoenzymes in this biological fluid. METHODS: Using the substrate 3,3'-dichlorophenolsulphoftaleinil N-acetyl-beta-D-glucosaminide, a highly significant difference (p<0.001) is found between the activation energy of Hex A (41.5 kJ/mol) and of Hex B (72.3 kJ/mol), making it possible to determine the activity of these isoenzymes from the apparent activation energy of the total Hex in seminal plasma. RESULTS: A significant difference between the normozoospermic and azoospermic groups was only found for Hex A isoenzyme activity (p<0.05), although with considerable overlapping between the values of both groups. Significant partial correlations were found for the total Hex, Hex A and Hex B activities with the immobile spermatozoa count (p<0.01) and for total Hex and Hex B with the dead spermatozoa count (p<0.05). In turn, Hex A had a significant partial correlation with the live spermatozoa count (p<0.05); however, Hex activity in seminal plasma of acromosomal origin appears to be of little importance in quantitative terms. CONCLUSIONS: It was not possible to confirm that total Hex activity in seminal plasma, or even of its isoenzymes Hex A and Hex B, is a suitable biochemical marker of azoospermia (efficiency< or =67%). The thermodynamic procedure described may be a useful alternative for the study of the Hex enzyme heterogeneity in spermatozoa. FAU - Casal, J Antonio AU - Casal JA AD - Laboratorio Central, Hospital Clínico Universitario, 15706 Santiago de Compostela, Spain. FAU - Vizcaíno, Luis AU - Vizcaíno L FAU - Garcia-Devesa, Jesús AU - Garcia-Devesa J