Ohio State - Nationwide Children's Hospital - Research For Muscle Biology and Disease
 

 

Paul Janssen , Ph.D.
Associate Professor

The Ohio State University
Department of Physiology & Cell Biology
Department of Internal Medicine, Division of Cardiovascular Medicine
200 Hamilton Hall
1645 Neil Avenue
Columbus, OH 43210

Phone: (614) 247-7838
Email: janssen.10@osu.edu

Education & Training:
Utrecht University, Netherlands, 1994 B.S.& M.S. in Medical Biology
Utrecht University, Netherlands, 1997 Ph.D. in Cardiac Physiology
Universities of Freiburg and Göttingen, Germany, 2000 Postdoctoral Fellow
Johns Hopkins University, Baltimore, 2002 Research Associate

Research Interest:
 Research in the Janssen lab focuses on various aspects of myocardial relaxation.  Cardiac relaxation is no longer thought to be a mere passive process that logically follows contraction, but is a highly regulated process, involving interactions between calcium removal systems and mechanical molecular motors.  We study relaxation using a minimalized systems approach, in which we have the advantage of working in a sub-organ level model (multicellular trabeculae) that still encompasses all the electrical, biochemical, and contractile functions of the whole heart, yet is small enough to control in vitro while allowing for assessment of intracellular events, such as calcium transients.  More than half of the patients suffering from heart failure (which kills more people than all cancers and aids combined) suffer from relaxation disorders, and part of our work is to gain understanding in the molecular events that change during progression to heart failure.  Using multicellular preparations, under near-physiological conditions, we assess contractile parameters and intracellular calcium handling.  In addition to the investigation of physiological relaxation, impaired relaxation is studies in several models, including pulmonary artery banded rabbits, and in various transgenic models in collaborative effects.  Additional research areas of interest in the lab, often in collaboration with other labs are aimed at understanding the role of hydroxyl-radical induced damage to the heart, inotropic therapy using glycolysis intermediates, the role of junction proteins in the heart, and cardiac insufficiency in muscular dystrophy disease.

Selected Publications:

  • Varian KD, Janssen PML. Frequency dependent acceleration of relaxation involves decreased myofilament calcium sensitivity. Am. J. Physiol. Heart. Circ. Physiol. 2007;292:H2212-2219.
  • Hiranandani N, Raman S, Kalyanasundaram A, Periasamy M, Janssen PML. Frequency-dependent contractile strength in mice over- and under-expressing the sarcoplasmic reticulum calcium ATPase. Am. J. of Physiol. Reg. Integr. Comp. Physiol. 2007;293:R30-R36.
  • Bupha-Intr T, Holmes JW, Janssen PML. Induction of hypertrophy in vitro by mechanical loading in adult rabbit myocardium. Am J. Physiol. Heart Circ. Physiol. 2007;293:H3759-H3767.
  • Monasky MM, Varian KD, Janssen PML. Gender comparison of contractile performance and b-adrenergic response in isolated rat cardiac trabeculae. J. Comp. Physiol. Biochem. 2008;178:307-313.
  • Monasky MM, Varian KD, Davis JP, Janssen PML. Dissociation of Force Decline from Calcium Decline by Preload in Isolated Rabbit Myocardium. Eur J Physiol., 2008;178:267-276.
  • Torres CAA, Varian KD, Janssen PML. Variability in interbeat duration influences myocardial contractility in rat cardiac trabeculae. Open Cardiovascular Medicine Journal, 2008; 2: 100-104.
  • Janssen PML, Zeitz O, Schumann H, Holtz J, Hasenfuss G. Load-induced apoptosis in cultured multicellular preparations is unaltered in presence of the b-adrenoceptor antagonist nebivolol. Pharmacology, 2009;83:141-147.
  • Monasky MM, and Janssen PML. The positive force-frequency relationship is maintained in absence of sarcoplasmic reticulum function in rabbit, but not in rat myocardium. J. Comp. Physiol. B. 2009; 179: 469-479.
  • Martin PT, Xu R, Rodino-Klapac LR, Oglesbay E, Camboni M, Montgomery CL, Shontz K, Chicoine LG, Clark KR, Sahenk Z, Mendell JR, Janssen PML. Overexpression of Galgt2 in skeletal muscle prevents injury resulting from eccentric contractions in both mdx and wild type mice. Am J Physiol Cell Physiol. 2009; 263: C476-488.
  • Bupha-Intr T, Haizlip KM, Janssen PML. Temporal changes in expression of connexin-43 after load-induced hypertrophy in vitro. Am J Physiol Heart Circ Physiol. 2009; 296: H806-814.