“It is important to draw wisdom from different places. If you take it from only one place it becomes rigid and stale. Understanding others, the other elements, the other nations, will help you become whole.”  –Uncle Iroh

Laura Szymanski, Ph.D.
Department of Biological Sciences
Lehigh University
111 Research Drive
Bethlehem PA, 18015
las4@lehigh.edu
(610) 758 5603

Curriculum Vitae

Current Research

My Ph.D. dissertation research focuses on the metabolic control of reproduction.  Specifically, I am investigating how the hypothalamic-pituitary-gonadal (HPG) axis recovers from energy deficits caused by alterations in diet.  Using both Syrian hamsters (Mesocricetus auratus) and sheep (Ovis aries) as animal models, I study the behavioral and physiological responses involved in the metabolic control of reproduction.

My work with hamsters is done at Lehigh University in the laboratory of my research advisor, Dr. Jill Schneider.  The short reproductive cycle of the hamster allows me to examine the general effects of diet manipulation on reproduction using estrous cycle length and lordosis behavior as markers of HPG function.

 

Questions I address in this research:

• What are the minimum caloric requirements for normal estrous cyclicity?
• Can a single macronutrient provide sufficient energetic signals to maintain estrous cyclicity after food deprivation?
• What are the effects of feeding a diluted diet on metabolic status and reproduction?
• Is the presence of glucose in the brain enough to maintain reproduction during food deprivation?

My work with sheep is done in the laboratory of Dr. Iain Clarke at Monash University in Clayton, Australia.  The large body size in the sheep enables me to measure the specific, rapid effects of diet manipulation on reproduction using pulsatile secretion of luteinizing hormone (LH) from the pituitary gland as a marker of HPG function. 

 

Questions I address in this research:

• How quickly does pituitary secretion of LH respond to the return to ad libitum food intake after chronic food restriction?
• Is this recovery accompanied by changes in body fat and/or plasma concentrations leptin? insulin? ghrelin? metabolic fuels?
• What changes in hypothalamic neuropeptide expression occur with recovery of pulsatile LH secretion?
• Will infusion of the volatile fatty acid, propionate stimulate pulsatile LH secretion as well as increases in food intake?

Technical skills

Surgery
ovariectomy
castration
stereotaxic surgery (icv cannulation, injections)
perfusion
micropump implantation

Animal handling
intraperitoneal and subcutaneous injections
blood sampling (cardiac puncture)     
serial blood sampling (via indwelling catheter)
breeding
lordosis testing
           
Other laboratory skills
microtome and cryostat brain sectioning
RIAs
microplate metabolic fuel assays
ELISAs

Future interests

My primary goal is to integrate my existing knowledge and skills with a further understanding of the molecular mechanisms involved in the regulation of the HPG system.  I aim to expand my research focus to include the mechanisms of hormone action in the brain as well as the neuroanatomical pathways involved in control of reproduction and fertility.  

 

Publications

Szymanski, L.A., Schneider, J.E., Friedman, M.I., Ji, H., Kurose, Y., Blache, D., Rao, A., Dunshea, F.R., and I.J. Clarke.  Changes in insulin, glucose and ketone bodies, but not leptin or body fat content precede restoration of luteinising hormones secretion in ewes. J Neuroendocrinology 2007 Jun; 19(6): 449-60

Schneider, J.E., Buckley, C.A., Blum, R.M., Zhou, D., Szymanski, L., Day, D.E., and T.J. Bartness.  Metabolic signals, hormones and neuropeptides involved in control of energy balance and reproductive success in hamsters. Eur J Neurosci. 2002 Aug; 16(3):377-9.  

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