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Benson T. Akingbemi, DVM, PhD
Assistant Professor of Anatomy, joined the College of Veterinary Medicine in August, 2004. He had his initial education in Nigeria where he received the D.V.M. (1980), M.Sc. (1988) and Ph.D. (1997) degrees from the University of Ibadan. With a Research Fellowship from the National Institutes of Health, Dr. Akingbemi came to the United States in 1997 for postdoctoral training. Between 1997 and 2004, he worked on environmental toxicology and Leydig cells with Dr. Matthew Hardy, Center for Biomedical Research of the Population Council, Rockefeller University, New York.
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Research Interests
The laboratory has interests in male reproductive biology and toxicology. The male sex steroid hormone, testosterone, which maintains the male phenotype, is produced primarily by Leydig cells in the testis. However, the concept that ‘androgen is male and estrogen is female’ is no longer tenable because estrogen receptors (ERα and ERβ) are localized, along with androgen receptors, to male reproductive tissues, including Leydig cells. Data from transgenic mice lacking one or both ER subtypes support the hypothesis that estrogen has a regulatory role in male reproduction. Moreover, there is growing public concern that chemicals in the environment (food, air, water), which have estrogenic properties, may have adverse effects on reproductive health. These compounds alter the endocrine profile by acting through steroid hormone receptors and are designated endocrine disruptors. We will engage in the investigation of the role of estrogen, the ER, and the effects of endocrine disruptors on Leydig cell differentiated function and male reproduction.
Selected Publications
vom Saal FS, Akingbemi BT, Belcher SM, Birnbaum LS, Crain DA, Eriksen M, Farabollini F, Guillette LJ Jr, Hauser R, Heindel JJ, Ho SM, Hunt PA, Iguchi T, Jobling S, Kanno J, Keri RA, Knudsen KE, Laufer H, Leblanc GA, Marcus M, McLachlan JA, Myers JP, Nadal A, Newbold RR, Olea N, Prins GS, Richter CA, Rubin BS, Sonnenschein C, Soto AM, Talsness CE, Vandenbergh JG, Vandenberg LN, Walser-Kuntz DR, Watson CS, Welshons WV, Wetherill Y, and Zoeller RT. (2007) Chapel Hill bisphenol A expert panel consensus statement: Integration of mechanisms, effects in animals and potential to impact human health at current levels of exposure. Reprod Toxicol. Jul 27.
Wetherill YB, Akingbemi BT, Kanno J, McLachlan JA, Nadal A, Sonnenschein C, Watson CS, Zoeller RT, Belcher SM. (2007) In vitro molecular mechanisms of bisphenol A action. Reprod Toxicol. May 29.
Akingbemi BT, Braden TD, Kemppainen BW, Hancock KD, Sherrill JD, Cook SJ, He X, Supko JG. (2007) Exposure to phytoestrogens in the perinatal period affects androgen secretion by testicular Leydig cells in the adult rat. Endocrinology. Jun 14.
Ge RS, Chen GR, Dong Q, Akingbemi B, Sottas CM, Santos M, Sealfon SC, Bernard DJ, Hardy MP. (2007) Biphasic effects of postnatal exposure to diethylhexylphthalate on the timing of puberty in male rats. J Androl. Jul-Aug;28(4):513-20. Epub Feb 7.
Akingbemi BT. (2005) Estrogen regulation of testicular function. Reproductive Biology and Endocrinology 3:51.
Akingbemi BT, Ge R, Klinefelter GR, Zirkin BR, Hardy MP. (2004) Phthalate-induced Leydig cell hyperplasia is associated with multiple endocrine disturbances. Proc Natl Acad Sci U S A 101(3):775-780.
Akingbemi BT, Sottas CM, Koulova AI, Klinefelter GR, Hardy MP. (2004) Inhibition of testicular steroidogenesis by the xenoestrogen bisphenol A is associated with reduced pituitary luteinizing hormone secretion and decreased steroidogenic enzyme gene expression in rat Leydig cells. Endocrinology 145:592-603.
Akingbemi BT, Ge R, Rosenfeld CS, Newton LG, Hardy DO, Catterall JF, Lubahn DB, Korach KS, Hardy MP. (2003) Estrogen receptor-α gene deficiency enhances androgen biosynthesis in the mouse Leydig cell. Endocrinology 144:84-93.
Akingbemi BT, Hardy MP. (2001) Oestrogenic and antiandrogenic chemicals in the environment: effects on male reproductive health. Ann Med 33:391-403.
Akingbemi BT, Youker RT, Sottas CM, Ge R, Katz E, Klinefelter GR, Zirkin BR, Hardy MP. (2001) Modulation of rat Leydig cell steroidogenic function by di(2-ethylhexyl)phthalate. Biol Reprod 65(4):1252-1259.
Akingbemi BT, Ge RS, Klinefelter GR, Gunsalus GL, Hardy MP. (2000) A metabolite of methoxychlor, 2,2-bis(p-hydroxyphenyl)-1,1, 1-trichloroethane, reduces testosterone biosynthesis in rat Leydig cells through suppression of steady-state messenger ribonucleic acid levels of the cholesterol side-chain cleavage enzyme. Biol Reprod 62(3):571-578.
Akingbemi BT, Ge RS, and Hardy MP. (1999) Leydig cells. In: Encyclopedia of Reproduction. Eds: E. Knobil and J.D. Neill Academic Press, San Diego, CA, pp. 1021-1033.
For more publications check out Pub Med
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