Helena (Elena) Parfenova, Ph.D.

Helena (Elena) Parfenova, Ph.D.

Department of Physiology

The University of Tennessee Health Science Center
894 Union Avenue
Memphis, TN 38163
Phone: (901) 448-8319
Fax: (901) 448-7126
Lab: 305 Nash Research Building
Email: Helena (Elena) Parfenova



  • Ph.D. Institution:¬†Institute of Cytology, St Petersburg, Russia


Research Interests

We investigate the roles of heme oxygenase (HO) and carbon monoxide (CO), the HO-derived endogenous gaseous mediator, in regulating blood flow to the brain and in promoting survival of brain endothelial cells during cerebral vascular insult caused by seizures and oxidative stress. Seizures cause sustained cerebral vascular injury, reduction of endothelial vasodilator function, and loss of cerebral blood flow regulation. Glutamate, an excitatory neurotransmitter, and TNFa, a pro-inflammatory cytokine, are major injurious factors involved in the pathogenesis of seizure-induced cerebral vascular injury and endothelial apoptosis. Activation of endogenous HO/CO system or pharmacological delivery of CO to the brain reduces or prevents cerebral vascular endothelial injury and restores cerebral vascular endothelial function.

Cerebral Vascular Endothelial Cells HO-2 Immunostaining (Green) F-Actin (Red)

We investigate the HO/CO system as a critical component of anti-apoptotic mechanisms involved in protecting the brain from cerebral vascular injury caused by seizures and oxidative stress. The projects involve in vivo and in vitro studies in newborn pigs using the closed cranial window techniques for detection of cerebral blood flow responses, isolated cerebral resistance arterioles, and primary cultures of cerebral vascular endothelial, smooth muscle, and glial cells. My ultimate goal is to translate the knowledge gained from the animal models to pediatric practice to correct the deteriorating neurological outcome of neonatal cerebrovascular insults

Research Support

  • Home Oxygenase and Cerebral Vascular Injury. NIHLBI/NIH. 6/1/4-5/31/14 P.I.
  • Cerebrovascular Stress and Circulating Endothelial Cells. NINDS/NIHLBI. 2/1/10-1/31/15 P.I.
  • Control of neonatal circulation. NHLBI/NIH. 4/1/1984-3/31/2017 (Co-I, CW Leffler, P.I.)
  • Hydrogen Sulfide in Newborn Cerebral Circulation. NIHLBI/NIH. 8/1/1990-7/31/2015 (Co-I, CW Leffler, P.I.)

Representative Publications