Synthia Mellon, PhD

Recall Professor
Department of Obstetrics Gynecology & Reproductive Sciences
Research Overview: 

Our laboratory studies the regulation of steroid hormone synthesis, by analyzing the transcriptional regulation of the steroidogenic enzymes, and the mechanism of action of steroids in both steroidogenic tissues and in the nervous system, where we identified the developmental and regional expression of steroidogenic enzymes and some novel actions of steroids on neuronal function. Steroid hormones are regulators of a multitude of physiologic processes, and act primarily by activating nuclear receptors, which are transcriptional regulators of various genes. However in the nervous system, where we found steroidogenic enzymes and synthesis of a novel class of steroid, called neurosteroids, neurosteroids modulate ion flux through the ion gated GABA A and NMDA receptors, and regulation of their synthesis results in changes in behavior, learning, and memory. We delineated the ontogeny and sites of steroidogenic enzyme expression , and showed that neurosteroids affect neuronal development by specifically modulating either axonal or dendritic growth and neuronal differentiation.Their actions throughout life may maintain the integrity of neural connections, and demise of neurosteroid synthesis may result in loss of memory associated with some age-related neurologic diseases. Our studies thus rely on a number of different experimental paradigms, from molecular biologic analysis of gene structure and transcription factors to developmental and cell biology of neuronal development and function.

Primary Thematic Area: 
Developmental & Stem Cell Biology
Secondary Thematic Area: 
Neurobiology
Research Summary: 
Developmental Regulation, Molecular Biology and Novel Actions of Steroid/Neurosteroid Synthesis
Publications: 

Correction: A DNA methylation clock associated with age-related illnesses and mortality is accelerated in men with combat PTSD.

Molecular psychiatry

Yang R, Wu GWY, Verhoeven JE, Gautam A, Reus VI, Kang JI, Flory JD, Abu-Amara D, Hood L, Doyle FJ, Yehuda R, Marmar CR, Jett M, Hammamieh R, Mellon SH, Wolkowitz OM

Pre-deployment risk factors for PTSD in active-duty personnel deployed to Afghanistan: a machine-learning approach for analyzing multivariate predictors.

Molecular psychiatry

Schultebraucks K, Qian M, Abu-Amara D, Dean K, Laska E, Siegel C, Gautam A, Guffanti G, Hammamieh R, Misganaw B, Mellon SH, Wolkowitz OM, Blessing EM, Etkin A, Ressler KJ, Doyle FJ, Jett M, Marmar CR

Pre-treatment allostatic load and metabolic dysregulation predict SSRI response in major depressive disorder: a preliminary report.

Psychological medicine

Hough CM, Bersani FS, Mellon SH, Morford AE, Lindqvist D, Reus VI, Epel ES, Wolkowitz OM

A DNA methylation clock associated with age-related illnesses and mortality is accelerated in men with combat PTSD.

Molecular psychiatry

Yang R, Wu GWY, Verhoeven JE, Gautam A, Reus VI, Kang JI, Flory JD, Abu-Amara D

Role of enhanced glucocorticoid receptor sensitivity in inflammation in PTSD: Insights from computational model for circadian-neuroendocrine-immune interactions.

American journal of physiology. Endocrinology and metabolism

Somvanshi PR, Mellon SH, Yehuda R, Flory JD, Bierer L, Makotkine I, Marmar C, Jett M, Doyle Iii FJ