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Mammary Cell Turnover under High Temperature during the Dry Period in Dairy Cows

  • Peng, Xiaoqing (College of Animal Science and Technology, Nanjing Agricultural University) ;
  • Lu, Lin (College of Animal Science and Technology, Nanjing Agricultural University) ;
  • Li, Yan (College of Animal Science and Technology, Nanjing Agricultural University) ;
  • Yan, Peishi (College of Animal Science and Technology, Nanjing Agricultural University)
  • Received : 2010.08.19
  • Accepted : 2010.12.08
  • Published : 2011.04.01

Abstract

The influence of high temperature on mammary cell turnover during the dry period is still unclear. The objective of this study was to investigate mammary cell turnover and p53 protein expression in the mammary tissue under high temperature conditions. Mammary gland biopsy samples from 8 dairy cows were obtained at 7, 25, 40, and 53 d during the dry period in summer or spring (n = 4, each season). Cell cycle, cell turnover, and p53 protein expression were analyzed by flow cytometry. During the dry period in summer, the percentage of mammary epithelial cells in the G0/G1 phase was the highest, but those in the S and G2/M phases were lower. However, the proportion of cells in the different stages of the cell cycle was not significantly different among the different biopsy time points, except in the G2/M phase. Under different temperature conditions, the cells were significantly different in their apoptotic rate and proliferation index; moreover, the tendencies of these indicators to change significantly differed. In general, the samples under high temperature conditions showed significantly lower apoptotic rates and proliferation indices. Under high temperature conditions, the apoptotic rate and proliferation index were the lowest (2.17% and 3.26%, respectively) at day 40, and the highest at day 53 (3.67% and 4.61%, respectively). However, under normal temperature conditions, the values of these indicators were the lowest (7.60% and 5.54%, respectively) at day 7, and almost the highest at day 25 (12.85% and 6.47%, respectively). Moreover, p53 protein expression was significantly higher under high temperature conditions than under normal temperature conditions, except at day 25. The level of p53 protein was the lowest (13.10%) under high temperature conditions at day 25, but was the highest (26.07%) under normal temperature conditions. Our findings suggest that high temperature delayed the G2/M phase of the cell cycle and the cell turnover rate, but remarkably increased p53 protein expression. Thus, the results indicate that high temperature extends the recovery period of mammary epithelial cells.

Keywords

References

  1. Breen, J. G., T. W. Claggett and G. L. Kimmel. 1999. Heat shock during rat embryo development in vitro results in decreased mitosis and abundant cell death. Reprod. Toxicol. 13:31-39. https://doi.org/10.1016/S0890-6238(98)00056-2
  2. Capuco, A. V., D. L. Wood and R. Baldwin. 2001. Mammary cell number, proliferation, and apoptosis during a bovine lactation: Relation to milk production and effect of bST. J. Dairy Sci. 84:2177-2187. https://doi.org/10.3168/jds.S0022-0302(01)74664-4
  3. Cavestany, D., A. B. Wishy and R. H. Foole. 1985. Effect of season and high environmental temperature on fertility of Holstein cattle. J. Dairy Sci. 68:1471-1478. https://doi.org/10.3168/jds.S0022-0302(85)80985-1
  4. Collier, R. J., S. G. Doelger and H. H. Head. 1982. Effects of heat stress during pregnancy on maternal hormone concentrations, calf birth weight and postpartum milk yield of holstein cows. J. Anim. Sci. 54:309-319.
  5. Du, J., H. S. Di and L. Guo. 2006. Influence of high temperature on growth and apoptosis in mammary epithelial cells. Actazoologica Sinica. 52:959-965.
  6. Jin, Z. H., H. Matsumoto and S. Hayashi. 2004. P53 independent thermosensitization by mitomycin c in human non-small-cell lung cancer cells. J. Radiat. Oncol. Biol. Phys. 59:852-860. https://doi.org/10.1016/j.ijrobp.2004.01.033
  7. Lee, Y. J., J. H. Kim and S. Ryu. 1994. Mechanisms of mild hyperthermia-induced cytotoxicity in human prostatic carcinoma cells: perturbation of cell cycle progression and DNA fragmentation. J. Therm. Biol. 19:305-313. https://doi.org/10.1016/0306-4565(94)90066-3
  8. Leidy, N. K. 1989. A Physiological analysis of stress and chronic illness. J. Adv. Nurs. 14:868-876. https://doi.org/10.1111/j.1365-2648.1989.tb01473.x
  9. Li, D. G., H. Wang and J. Q. Wang. 2005. Effect of dry period lengths on growth performance and health in cows. Hei Longjiang Animal Science and Veterinary Medicine 8:17-20.
  10. Lim, C. U., Y. Zhang and M. H. Fox. 2006. Cell cycle dependent apoptosis and cell cycle blocks induced by hyperthermia in HL-60 cells. Int. J. Hyperthermia 22:77-91. https://doi.org/10.1080/02656730500430538
  11. McGrath, M. F. 1987. A novel system for mammary epithelial cell culture. J. Dairy Sci. 70:1967. https://doi.org/10.3168/jds.S0022-0302(87)80239-4
  12. Mu, S. Q. 1989. Influence of climate on milk production and formation in cows. Acta Ecologae Animalis Domastici 2:46-47.
  13. Narita, M., S. Shimizu and T. Ito. 1998. Bax interacts with the permeability transition pore to induce permeability transition and cytochrome c release in isolated mitochondria. Proc. Nat. Acad. Sci. USA. 95:14681-14686. https://doi.org/10.1073/pnas.95.25.14681
  14. Neill, K. L., D. W. Fairbairn and M. J. Smith. 1998. Critical parameters influencing hyperthermia induced apoptosis in human lymphoid cell lines. Apoptosis 3:369-375. https://doi.org/10.1023/A:1009689407261
  15. Oliver, S. P. and L. M. Sordillo. 1989. Approaches to the manipulation of mammary involution. J. Dairy Sci. 72:1647-1664. https://doi.org/10.3168/jds.S0022-0302(89)79277-8
  16. Oren, M. 1999. Regulation of the p53 tumor suppressor protein. J. Biol. Chem. 274:36031-36034. https://doi.org/10.1074/jbc.274.51.36031
  17. Smith, K. L. and D. A. Todhunter. 1982. The physiology of mammary glands during the dry period and the relationship to infection. in Proc. Natl. Mastitis Counc., Louisville, KY. Natl. Mastitis Counc. Inc., Arlington, VA. 87.
  18. Sorensen, M. T., J. V. Norgaard and P. K. Theil. 2006. Cell turnover and activity in mammary tissue during lactation and the dry period in dairy cows. J. Dairy Sci. 89:4632-4639. https://doi.org/10.3168/jds.S0022-0302(06)72513-9
  19. Tadashi, K., K. Takao and N. Takeo. 2004. Mild heat shock induces autophagic growth arrest, but not apoptosis in U251-MG and U87-MG human malignant glioma cells. J. Neuro. Oncol. 68:101-111. https://doi.org/10.1023/B:NEON.0000027739.33842.6c
  20. West, J. W., B. G. Mullinix and J. K. Bernard. 2003. Effects of hot, humid weather on milk temperature, dry matter intake, and milk yield of lactating dairy cows. J. Dairy Sci. 86:232-242. https://doi.org/10.3168/jds.S0022-0302(03)73602-9