Susan Howlett


Dr. Howlett

Related information


Phone: 902-494-3552
Mailing Address: 
Room 6D, Sir Charles Tupper Medical Building, 5850 College Street, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2
Research Topics:
  • Aging
  • Frailty
  • Hormonal regulation of cardiac function
  • Estrogen and testosterone
  • Cardiac excitation-contraction coupling
  • Myocardial ischemia and reperfusion
  • Pathways involved in aging / frailty
  • Pathways involved in aging / frailty


  • BSc (Concordia University)
  • MSc (Memorial University of Newfoundland)
  • PhD (Memorial University of Newfoundland)
  • PDF (University of Alberta)

Research interests

Dr. Howlett is well known for her work on cardiac contraction and its regulation in health and disease. She has discovered profound differences in the way male and female heart cells function and how these changes are affected by age and overall health (frailty). She has pioneered the measurement of frailty in aging animals with a "frailty index", a major advance that will help translate scientific discoveries in aging research into meaningful clinical interventions.

Selected publications

  • Ghimire A, Bisset ES, Howlett SE. Ischemia and reperfusion injury following cardioplegic arrest is attenuated by age and testosterone deficiency in male but not female mice. Biol Sex Differ. 2019;10(1):42

  • Heinze-Milne SD, Banga S, Howlett SE. Frailty Assessment in Animal Models. Gerontology. 2019;65(6):610-619

  • Ayaz O, Banga S, Heinze-Milne S, Rose RA, Pyle WG, Howlett SE. Long-term testosterone deficiency modifies myofilament and calcium-handling proteins and promotes diastolic dysfunction in the aging mouse heart. Am J Physiol Heart Circ Physiol. 2019;316(4):H768-H780

  • Keller K, Kane A, Heinze-Milne S, Grandy SA, Howlett SE. Chronic Treatment With the ACE Inhibitor Enalapril Attenuates the Development of Frailty and Differentially Modifies Pro- and Anti-inflammatory Cytokines in Aging Male and Female C57BL/6 Mice. J Gerontol A Biol Sci Med Sci. 2019;74(8):1149-1157

  • Kane AE, Keller KM, Heinze-Milne S, Grandy SA, Howlett SE. Murine Frailty Index Based on Clinical and Laboratory Measurements: Links Between Frailty and Pro-inflammatory Cytokines Differ in a Sex-Specific Manner. J Gerontol A Biol Sci Med Sci. 2019;74(3):275-282.