SPERMATOZOA AGING IS SLOWED DOWN IN ZMF

Z.Truţă, Silvia Neamţu, V.V. Morariu

National Institute for R&D of Isotopic and Molecular Technologies, P.O.Box 700, Cluj-Napoca 5, 400293, Romania

The spermatozoa are motile specialized cells which are classified in rapid progressive and slow progressive groups bordered by a velocity of 16 μm/s. The rapid progressive spermatozoa group is in fact responsible for fertilization. In vivo conditions (human body temperature 370C) these cells live up to 48 hours. The decrease of spermatozoa velocity and the shift from the rapid to slow progressive cells group is a measure of the aging of cells population. In our previous experiments we found a significant difference of the motility and viability of these cells in experimental zero magnetic fields (ZMF) compared with geomagnetic field (GMF) conditions [1]. As a result of these findings the influence of the temperature on spermatozoa aging in ZMF was investigated. 
Human spermatozoa were exposed in ZMF and GMF as control in 17-220C range of temperature. The cells viability was estimated microscopically at 3 hour interval. In order to define the rapid spermatozoa, a computer analysis display system was used to track sequentially the movement of cells. The aging curve and ZMF effect were determined. The results indicate that the spermatozoa aging was significantly increased in the first hours of exposure in GMF at temperatures less than 200C. On the other hand this process was strongly slowed down in ZMF conditions. So, even though the cells viability normally decreases, it was maintained at 90% in the first 3 hours of cells exposure in ZMF at 170C while in GMF roughly entire cells population became immobile or slow progressive. At 190C the rapid spermatozoa cells viability was 100% up to 8 hours. At higher temperatures the cells aging process was diminished both in GMF and ZMF. However the process was significantly delayed in ZMF. These results showed that ZMF is a protective environment against spermatozoa aging.
ZMF effect on spermatozoa is opposite to the effect recorded on other type of motile cells. For instance the ciliate apparatus of ependymal cells in newborn rats in vivo is inhibited up to absolute stoppage in hypomagnetic field [2]. Also our investigation showed the same ZMF effect on bacterial cells (Listeria sp.)
	Based on the similarities and differences of the response of other type of cells to ZMF, questions arise regarding specific basic functions interdependences. Work is in progress to respond to these questions.

References:
      
1.	Z. Truta, S. Neamtu; V.V. Morariu , The influence of zero magnetic field on in vitro humen spermatozoa cells behavior, 8th Romanian Biophysics Conference “Advances Biomaterials and Biophysical Techniques, Mai, 26-28 (2005) 
2.	V. Sandodze , I.K. Swnidze , E.V. Didimova; Effect of hypomagnetic fields on motility of the cilia of ependimal cells in vivo, Radiats Biol Radioecol , nr.35, vol1, 19-22 (1995)