Fellowship for Xuan Nguyen: Dynorphin in Age-Related Impairment of Learning/Memory

Course No. Course Name Credits Grade MD 820 Patients, Physicians & Society II 5 A MD 821 Introduction to the Medical Profession II 7 A MI 822 Immunity, Infection & Disease 9 A PAT 823 Disease and Treatment / Pathology 9 A PGY 825 Second-year elective: Physiology 2 P PHA 824 Disease and Treatment / Phannacology 8 A PSC 826 MDT / Psychiatry 2 A Table 1. Courseworktakenduringacademicyear 2002-03. PROGRESS REPORT: The majority of the fellowship term was spent in full-time medical coursework as listed in Table 1. The fellow has completed the medical school basic sciences curriculum with an annual GPA of 4.0 and a cumulative College of Medicine GPA of 3.97. The College of Medicine Student Progress and Promotions Committee has granted him a one-year academic leave of absence from the M.D. program to continue Ph.D. study for the 2003-04 academic year, contingent upon successful completion of Step I of the U.S. Medical Licensure Examination, which was attempted on June 12,2003. The research during this period continued as planned, with further neurobiological and biochemical characterization of the prodynorphin (Pdyn) knockout (-/-) mice along with other studies to test the potential role of prodynorphin-derived peptides in CNS changes associated with aging. The hypothesis of a detrimental effect of long-term dynorphin exposure in the brain with aging has been supported by literature reports of increased dynorphin levels not only after CNS trauma or excitotoxic insult but also with normal aging in rats, especially if concomitant cognitive deficits are present. To evaluate this premise in the particular mouse strain used in our behavioral experiments, radioimmunoassay for the dynorphin A peptide was performed in various regions of the wild-type (WT) 129SvEv mouse brain and showed that dynorphin A increases with aging in frontal cortex and striatum, but not hippocampus (Figure 1).