Marc Lenoir

Marc Lenoir
Researcher INSERM - Montpellier

Marc Lenoir began its research activity in 1977, in Rémy Pujol’s laboratory (“Laboratory of sensory physiology”) in Marseille (France)  where he learned cochlear histology and electrophysiology. In 1980, he joined the team of Armand Dancer in the laboratory of Experimental Acoustic in Saint Louis (France) for one year. Then, he followed Rémy Pujol in Montpellier and entered INSERM in 1982 (INSERM U254, “Neurobiology and pathophysiology of cochlear and vestibular development”, director : Rémy Pujol). In 1983, he spent half a year at the MRC Institute for Hearing Research (Notthingam, UK) to study oto-acoustic emissions in the mouse under the direction of Gregory Bock. Since 2003, he works in INM (Institut of Neuroscience of Montpellier, INSERM U583, untitled: Pathophysiology et therapy of sensory and motor défects), directed by Christian Hamel. He belongs to the team of Jean-Luc Puel (who replaces Rémy Pujol since 2003), working on the pathophysiology and therapy of the inner ear. Beside its research activity, Marc Lenoir is involved as scientific referent in the INM plateform of Sensory and Motor Functional Exploration.

Main achievements :

Early achievements concerned the normal (Lenoir et al., 1980; 1987) and pathological (Lenoir and Pujol, 1984) development of the cochlea in rodents. He also compared the ultrastructural organization of the cochlea in different animal models with particular hearing competences (Raphael et al., 1991; Vater and Lenoir, 1992; Vater et al., 1992-93). Then, he came to the regenerative potential of the organ of Corti demonstrating that supporting cells attempted to regenerate new hair cells in the amikacin damaged rat cochlea (Lenoir and Vago, 1996; Parietti et al., 1998; Daudet et al., 1998). His most recent data in this pathological model show that calpain is involved in hair cell death (Ladrech et al., 2004) and suggest that inflammatory process could play a role in both repair and degeneration of the organ of Corti (Ladrech et al., 2007).


Research interests :

The functional-anatomy of the organ of Corti in different innate and pathological models.
Specific questions:
• Why the organ of Corti does not regenerate lost hair cells and why the supporting cells fail to transdifferentiate completely into hair cells?
• Which cellular and molecular factors are involved in the repair and the degeneration of the organ of Corti after hair cell loss?


Selected publications :

  • Ladrech S, Guitton M, Saido T, Lenoir M. 2004. Calpain activity in the amikacin-damaged rat cochlea. J Comp Neurol. 477:149-60.
  • Daudet N, Vago P, Ripoll C, Humbert G, Pujol R and Lenoir M. 1998. Characterization of atypical cells in the juvenile rat organ of corti after aminoglycoside ototoxicity. J Comp Neurol. 401 : 145-62.
  • Pujol R , Lavigne-Rebillard M and Lenoir M. 1997. Development of sensory and neural structures in the mammalian cochlea. In: "Development of the Auditory System", E.W. Rubel, A.N. Popper and R.R. Fay (eds) Springer Handbook of Auditory Research, vol. XII, Springer, New-York, pp: 146-192.
  • Vater M and Lenoir M. Ultrastructure of the horseshoe bat's organ of Corti. I. Scanning electron microscopy. J Comp Neurol, 1992, 318 : 367-379.
  • Lenoir M, Puel J-L and Pujol R. SEM study of the rat cochlear development with emphasis on stereocilia and tectorial membrane. Anat. Embryol., 1987, 175, 477-487.
  • Lenoir M, Pujol R. Age-related structural investigation of the Bronx waltzer mutant mouse cochlea: scanning and transmission electron microscopy. Hear Res. 1984, 13:123-34.
  • Lenoir M, Shnerson A, Pujol R Cochlear receptor development in the rat with emphasis on synaptogenesis. Anat Embryol. 1980, 160:253-62.
  • Lenoir M, Bock GR and Pujol R. Supra-normal susceptibility to acoustic trauma of the rat pup cochlea. J Physiol (Paris). 1979, 75:521-4.