Linda McLoon, Ph.D.

Professor, Department of Ophthalmology and Visual Neurosciences; Department of Neuroscience

E-MAIL: mcloo001@umn.edu

Research Interests:

My laboratory focuses on understanding the potential mechanisms for two types of eye movement disorders: strabismus and nystagmus. Untreated these result in decreased visual acuity. Both involve the ocular motor system and the specialized skeletal muscles that move the eye, the extraocular muscles (EOM). We focus on the ability of retrogradely transported neurotrophic factors to alter the function and structure of the ocular motor system with the goal of developing a permanent therapeutic approach for these movement disorders. We have used RNAseq data to identify potential new therapeutic targets for development of treatments.

A second focus is the study of the muscle stem cell populations in the EOM that cause their differential sparing in degenerative disorders such as muscular dystrophy and amyotrophic lateral sclerosis. We have identified a specific stem cell, expressing Pitx2, which we have implicated in this differential sparing. Further work will focus on using these stem cells to prevent limb muscle degeneration in these currently untreatable diseases.


Selected Publications:

(For a comprehensive list of recent publications, refer to PubMed, a service provided by the National Library of Medicine.)

  • McLoon LK, Redish AD. Demystifying graduate school: Navigating a PhD in neuroscience and beyond. J. Undergrad. Neurosci. Educ. 2018;16:A203-A209.
  • Fitzpatrick KR, Cucak A, McLoon LK. Changing muscle function with sustained glial derived neurotrophic factor treatment of rabbit extraocular muscle. PLoS One. 2018 Aug 24;13(8):e0202861.
  • McLoon LK, Vincente A, Fitzpatrick KR, Lindström M, Pedrosa-Domellöf F. Composition, architecture, and functional implications of the connective tissue network of the extraocular muscles. Invest Ophthalmol Vis Sci. 2018;59:322-329.
  • Hebert SL*, Fitzpatrick KR*, McConnell SA, Cucak A, Yuan C, McLoon LK. Effects of retinoic acid signaling on extraocular muscle myogenic precursor cells in vitro. Exp Cell Res. 2017;361:101-111.
  • Verma M, Fitzpatrick KR, McLoon LK. Extraocular muscle repair and regeneration. Current Ophthalmology Reports. Invited review. 2017;5:207-215.
  • McLoon LK*, Christiansen SP, Ghose GM, Das VE*, Mustari MJ*. Improvement in eye alignment in adult strabismic monkeys by sustained IGF-1 treatment. Invest Ophthalmol Vis Sci. 2016;57:6070-6078.
  • Nelson KR, Stevens SM, McLoon LK. Prolongation of relaxation time in extraocular muscles with brain derived neurotrophic factor in adult rabbit. Invest Ophthalmol Vis Sci. 2016;57:5834-5842.
  • Yuan C, Bothun ED, Hardten DR, Tolar J, McLoon LK. A novel component of corneal opacification in a bone marrow transplant-treated patient with Hurler syndrome. Exp Eye Res. 2016;148:83-89.
  • McLoon LK, Willoughby CL, Anderson JS, Bothun ED, Stager DR, Felius J, Lee H, Gottlob I. Abnormally small neuromuscular junctions in the extraocular muscles from subjects with idiopathic infantile nystagmus and nystagmus associated with albinism. Invest Ophthalmol Vis Sci. 2016;57:1912-1920.
  • McDonald AA, Hebert SL, McLoon LK. Sparing of the extraocular muscles in mdx mice with absent or reduced utrophin expression: A life span analysis. Neuromusc Disord. 2015;25:873-887.
  • Graber TG, Kim JH, Grange RW, McLoon LK, Thompson LV. C57BL/6 life span study: age-related declines in muscle power production and contractile velocity. Age. 2015;37(3):9773.
  • Willoughby CL, Fleuriet J, Walton MM, Mustari MJ, McLoon LK. Adaptability of the immature ocular motor control system: Unilateral IGF-1 medial rectus treatment. Invest Ophthalmol Vis Sci. 2015;56:3484-96.
  • Willoughby CL, Fleuriet J, Walton MM, Mustari MJ, McLoon LK. Adaptation of slow myofibers: the effect of sustained BDNF treatment of extraocular muscles in infant nonhuman primates. Invest Ophthalmol Vis Sci. 2015;56:3467-83.
  • McDonald AA, Hebert SL, Kunz MD, Ralles SJ, McLoon LK. Disease course in mdx:utrophin+/- mice: comparison of three mouse models of Duchenne muscular dystrophy. Physiol Rep. 2015;3(4):e12391.
  • Walton MM, Mustari MJ, Willoughby CL, McLoon LK. Abnormal activity of neurons in abducens nucleus of strabismic monkeys. Invest Ophthalmol Vis Sci. 2014;56:10-19.
  • McLoon LK, Harandi VM, Brännström T, Andersen PM, Liu JX. Wnt and extraocular muscle sparing in amyotrophic lateral sclerosis. Invest Ophthalmol Vis Sci. 2014;55(9):5482-5496.
  • McDonald AA, Kunz MD, McLoon LK. Dystrophic changes in extraocular muscles after gamma irradiation in mdx:utrophin+/- mice. PLoS One. 2014;9(1):e86424.
  • Stager DR, McLoon LK, Felius J. Postulating a role for connective tissue elements in inferior oblique overaction. Trans. Am. Ophthalmol. Soc. 2013;111:119-32.
  • Hebert SL, Daniel ML, McLoon LK. The role of Pitx2 in maintaining the phenotype of myogenic precursor cells in the extraocular muscles. PLoS One 2013;8(3):e58405.
  • Willoughby CL, Christiansen SP, Mustari MJ, McLoon LK. Effects of the sustained release of IGF-1 on extraocular muscle of the infant non-human primate: Adaptations at the effector organ level. Invest. Ophthalmol. Vis Sci. 2012;53: 68-75.
  • Berg, KT, Hunter DG, Bothun ED, Antunes-Foschini R, McLoon LK. Extraocular muscles in subjects with infantile nystagmus: Adaptations at the effector level. Arch. Ophthalmol. 2012; 130:1-8.
  • McLoon LK, Park H, Kim JH, Pedrosa-Domellöf F, Thompson LV. A continuum of myofibers in adult rabbit extraocular muscle: force, shortening velocity, and patterns of myosin heavy chain co-localization. J. Appl. Physiol. 2011;111: 1178-1189.
  • Anderson BC, Daniel ML, Kendall J, Christiansen SP, McLoon LK. Sustained release of bone morphogenetic protein-4 in adult rabbit extraocular muscle results in decreased force and muscle size: potential for strabismus treatment. Invest. Ophthalmol. Vis. Sci. 2011;52:4021-4029.
  • Kallestad KM, Hebert SL, McDonald AA, Daniel ML, Cu SR, McLoon LK. Sparing of extraocular muscle in aging and dystrophic skeletal muscle: A myogenic precursor cell hypothesis. Exp. Cell Res. 2011;317:873-885..

Book Chapters:

  • Andrade FH, McLoon LK. The Craniofacial Muscles: Arguments for Uniqueness. In: Craniofacial Muscles: A New Framework for Understanding the Effector Side of Craniofacial Muscles. Eds: LK McLoon, F Andrade. Springer, 2012; pp. 3-7.
  • McLoon LK, Willoughby CL, Andrade FH. Extraocular Muscles: Structure and Function. In: Craniofacial Muscles: A New Framework for Understanding the Effector Side of Craniofacial Muscles. Eds: LK McLoon, F Andrade. Springer, 2012; pp. 31-88.
  • Hebert SL, Willoughby CL, Andrade FH, McLoon LK. Masticatory Muscles: Response to Neuromuscular Diseases and Specific Pathologies. In: Craniofacial Muscles: A New Framework for Understanding the Effector Side of Craniofacial Muscles. Eds: LK McLoon, F Andrade. Springer, 2012; pp. 131-138.
  • McLoon LK, Andrade FH. Comparison of Craniofacial Muscles: A Unifying Hypothesis. In: Craniofacial Muscles: A New Framework for Understanding the Effector Side of Craniofacial Muscles. Eds: LK McLoon, F Andrade. Springer, 2012; pp. 325-335.
  • McLoon LK. The Extraocular Muscles, Chapter 7, In: Adler’s Physiology of the Eye, 11th edition, Eds: Kaufman P, Alm A, Levin LA, Nilsson S, Ver Hoeve J, Wu SM. Elsevier. New York. pp. 182-207, 2011.
  • McLoon LK and Christiansen SP. Extraocular Muscles: Extraocular Muscle Anatomy. In: Ocular Periphery and Disorders, (ed. DA Dartt, P Bix, P D’Amore, R Dana, LK McLoon, JY Niederkorn) Oxford: Academic Press. pp. 17-26, 2011.
  • Christiansen SP, McLoon LK. Extraocular Muscles: Functional Assessment in the Clinic, Elsevier Encyclopedia of the Eye In: Ocular Periphery and Disorders, (ed. DA Dartt, P Bix, P D’Amore, R Dana, LK McLoon, JY Niederkorn) Oxford: Academic Press. 2011; pp. 45-48.
  • Semmer AE, McLoon LK, Lee MS. Orbital Vascular Anatomy. In: Immunology, Inflammation, and Diseases of the Eye, (ed. DA Dartt, R Dana, P D’Amore, J Niederkorn) Oxford: Academic Press; 2011.

Current Graduate Students:

Nathalia Torres Jimenez (Neuroscience, University of Minnesota).
Laura Johnson (Molecular, Cellular, Developmental Biology and Genetics Graduate Program)
 

Former Graduate Students:

Christy Willoughby (Ph.D. 2015, Neuroscience, University of Minnesota).

Abby McDonald (Ph.D. 2013; Molecular, Cellular, Developmental Biology and Genetics, University of Minnesota)

Sandra Alcala (Ph.D. 2009, Neuroscience, University of Minnesota).

Kristen Kallestad (Ph.D. 2009, Neuroscience, University of Minnesota).

Linda McLoon