Cynthia Jordan, Ph.D.
The expression of some behaviors, like reproductive behaviors, depends on appropriate exposure to sex hormones during development and in adulthood. Two main questions emerge from this observation that guide Jordan’s research: which cells among thousands do sex hormones directly affect to trigger changes in behavior, and what are the molecular pathways involved. Most studies to date use a neuromuscular model system (the SNB) in rodents that is both profoundly sensitive to gonadal androgens and sexually dimorphic. Unlike most other neuromuscular systems in rodents, the SNB system requires gonadal androgens for its survival and growth. Recent work includes characterizing the expression of androgen receptors and steroid receptor coregulators, examining the role of NMDA receptors and neurotrophic factors in androgen-regulated neural plasticity and assessing the cellular basis of hormone-dependent sexual dimorphisms in the brain, including analyses of brain neurons and glia. Development of a new transgenic mouse model has led to studying a motoneuron disease known as spinal bulbar muscular atrophy or Kennedy’s disease, a slowly progressing neuromuscular disease that affects men and involves the androgen receptor. Studying this disease model is a major focus of ongoing work in the lab.
Dr. Jordan’s research is now directed toward three main goals:
1. understanding the mechanisms by which androgens keep certain motoneurons alive and healthy
2. understanding the mechanisms by which androgens under certain circumstances can trigger the demise and, ultimately, the death of motoneurons
3. understanding the role of glia in steroid effects on brain and behavior
Johnson, R. T., Schneider, A., DonCarlos, L. L., Breedlove, S. M., & Jordan, C. L. (2012). Astrocytes in the rat medial amygdala are resposive to adult androgens. Journal of Commparative Neurology 520, 2531-2544.
Smith, M. R., Hamson, D. K., Poort, J. E., Jordan, C. L., & Breedlove, S. M. (2012). Ontogeny of androgen receptor expression in spinal nucleus of the bulbocavernosus motoneurons and their target muscles in male mice. Neuroscience Letters 513, 119-123.
Kemp, M. Q., Poort, J. L., Baqri, R. M., Liberman, A. P., Breedlove, S. M., Miller, K. E., & Jordan, C. L. (2011). Impaired motoneuronal retrograde transport in two models of SBMA implicates two sites of androgen action. Human Molecular Genetics, 20, 4475-4490.
Zuloaga, D. G., Poort, J. E., Jordan, C. L., & Breedlove, S. M. Male rats with the testicular feminization mutation of the androgen receptor display elevated anxiety-related behavior and corticosterone response to mild stress. Hormones and Behavior, 60, 380-388.
Zuloaga, D. G., Jordan, C. L., & Breedlove, S. M. (2011). The organizational role of testicular hormones and the androgen receptor in anxiety-related behaviors and sensorimotor gating in rats. Endocrinology, 152, 1572-1581.
Johansen, J. A., Troxell-Smith, S. M., Yu, Z. G., Mo, K. G., Monks, D. A., Lieberman, A. R., Breedlove, S. M., & Jordan, C. L. (2011). Prenatal flutamide enhances survival in a myogenic mouse model of spinal bulbar muscular atrophy. Neurodegenerative Diseases, 8, 25-34.
Ottem, E. N., Poort, J. E., Wang, H., Jordan, C. L., & Breedlove, S. M. (2010). Differential expression and regulation of brain-derived neurotrophic factor (BDNF) mRNA isoforms in androgen-sensitive motoneurons of the rat lumbar spinal cord. Molecular and Cellular Endocrinology, 328, 40-46.
Puts, D. A., Cardenas, R. A., Bailey, D. H., Burriss, R. P., Jordan, C. L., & Breedlove, S. M. (2010). Salivary testosterone does not predict mental rotation performance in men or women. Hormones and Behavior, 58, 282-289.
Johnson, R. T., Breedlove, S. M., & Jordan, C. L. (2010). Astrocytes in the amygdala. Vitamins and Hormones, 82, 23-45.
Pappas, S. S., Tiernan, C. T., Behrouz, B., Jordan, C. L., Breedlove, S. M., Goudreau, J. L., & Lookingland, K. J. (2010). Neonatal androgen-dependent sex difference in lumbar spinal cord dopamine concentrations and the number of A(11) diencephalospinal dopamine neurons. Journal of Comparative Neurology, 518, 2423-2436.