Contact : +54 351 5353855




Associate Researcher CONICET
Phone: 543515353855 ext 3428

Research Topic

Study of retinal degeneration mechanism in a models of light damage by LED source exposure.

In vertebrates, the retina is adapted to capturing light photons and transmitting this information to other structures in the central nervous system. In mammals, light acts directly on the retina to fulfill two important roles: (1) the visual function through rod and cone photoreceptor cells and (2) non-image forming tasks, such as the synchronization of circadian rhythms to a 24 h solar cycle, pineal melatonin suppression and pupil light reflexes. However, the excess of illumination may cause retinal degeneration or accelerate genetic retinal diseases. In the last century human society has increased its exposure to artificial illumination, producing changes in the Light/Dark cycle, as well as in light wavelengths and intensities. Although, the consequences of unnatural illumination or light pollution have been underestimated by modern society in its way of life, light pollution may have a strong impact on people’s health. The effects of artificial light sources could have direct consequences on retinal health. Constant exposure to different wavelengths and intensities of light promoted by light pollution may produce retinal degeneration as a consequence of photoreceptor or retinal pigment epithelium cells death.

We study the mechanism of retinal degeneration by photoreceptors cell death in a model of albino Wistar rats exposes at different times of white LED (200 lux).

Selected Publications

  • Photoreceptor damage induced by low-intensity light: model of retinal degeneration in mammals. Contin MA, Arietti MM, Benedetto MM, Bussi C, Guido ME. Mol Vis. 2013 Jul 25;19:1614-25. Print 2013.
  • Early onset and differential temporospatial expression of melanopsin isoforms in the developing chicken retina. Verra DM, Contin MA, Hicks D, Guido ME. Invest Ophthalmol Vis Sci. 2011 Jul 7;52(8):5111-20. doi: 10.1167/iovs.11-75301.
  • Light activation of the phosphoinositide cycle in intrinsically photosensitive chicken retinal ganglion cells. Contin MA, Verra DM, Salvador G, Ilincheta M, Giusto NM, Guido ME. Invest Ophthalmol Vis Sci. 2010 Nov;51(11):5491-8. doi: 10.1167/iovs.10-5643. Epub 2010 Jun 10.
  • An invertebrate-like phototransduction cascade mediates light detection in the chicken retinal ganglion cells. Contin MA, Verra DM, Guido ME. FASEB J. 2006 Dec;20(14):2648-50. Epub 2006 Oct 31.
  • Inner retinal circadian clocks and non-visual photoreceptors: novel players in the circadian system. Guido ME, Garbarino Pico-E, Contin MA, Valdez DJ, Nieto PS, Verra DM, Acosta-Rodriguez VA, de Zavalía N, Rosenstein RE. Prog Neurobiol. 2010 Dec;92(4):484-504. doi: 10.1016/j.pneurobio.2010.08.005. Epub 2010 Aug 22. Review.

(See more publications-CONICET)


Current Grants

  • Ministry of Science and Technology, UNC (SECyT-UNC). Awarded to Dr. Maria Ana Contin (AND). Draft: study light-induced retinal degenerations: model of retinal degeneration.
  • National Agency for Scientific and Technological Promotion "Study on the mechanisms of retinal degeneration in retinitis pigmentosa model". PICT-2012-0364.

Brief CV

Academic Formation

  • Biologist: 1996
  • PhD in Chemist: 2001
  • Researcher CONICET: 2005 to date.
  • Assistant Professor in Faculty of Chemistry, Universidad Nacional de Córdoba.

Research Background

The consequences of permanent light exposure are still unknown and even analyzing all knowledge in retinal light damage, we cannot rule out the risk of a chronic (intermittent or not) or high exposure to light promoted by light pollution on visual system. Cones, rods, retinal pigment epithelium, and intrinsically photosensitive retinal ganglion cells could be affected by high or prolonged light exposure induced by habits of modern life. Cumulative effects, long exposure by absence of profound experiences of dark during the night and high irradiance exposure by LED technology may affect the retinal physiology promoting cell death and the consequent blindness and desynchrony. The background knowledge about high- or low-light retinal damage in different animal models, allow us to speculate the potential damage that this kind of luminance could cause in the human retinal health. Light pollution may increment or accelerate oxidation mechanisms in which antioxidants defenses cannot revert these processes and the simple exposure during different periods to unnatural illumination during dark could produce retinal damage. In addition, light pollution could be a trigger for inherited diseases such as AMD and RP, promoting early onset of symptoms or accelerating the retinal degeneration processes. Furthermore, due to photoreceptor cells’ death (cone, rod, and intrinsically photosensitive retinal ganglion cells), unnatural illumination could add effects of desynchronization of the circadian system or cause malfunctions in pupillary light reflex or other non-imaging forming tasks. The intensities, duration, and spectrum of wavelength light that are using as artificial sources should be taken into account in future research. The information retrievable on in vitro and in vivo models in different animals will be useful for the knowledge of retinal degeneration mechanisms, and for discovery of drugs that can prevent or revert these processes. However, at time to compare the knowledge, we must not lose sight of the differences in the eye anatomy between species. Several strategies could be used to minimize it and address experimental condition that may not be performed in primates by the system complexity. For example, the use of filters that do not let pass wavelength absorbed by rodent cornea to simulate the primate cornea; or the use of total retina of rat (without macula and low cones) to study the rod photoreceptors cell death, could be useful to non-primate animal models and therefore resemble primates. Maybe, by ecological advantages, it is difficult to reduce the use of LED, so the application of appropriate filters may prevent the intensities of blue light; decreasing upon arrival to the eye, improving the lighting system, and decreasing the risk of retinal degeneration. Basic research can help about this regard.


  • Animal model in Wistar rats
  • Electroretinogram (VERY)
  • Inmunohistochemist
  • confocal microscopy analysis
  • protein analysis by wester blot
  • HPLC
  • Flow cytometry analysis