title: The role of dinucleoside polyphosphates on the ocular surface and other eye structures.
abstract: Dinucleoside polyphosphates comprises a group of dinucleotides formed by two nucleosides linked by a variable number of phosphates, abbreviated NpnN (where n represents the number of phosphates). These compounds are naturally occurring substances present in tears, aqueous humour and in the retina. As the consequence of their presence, these dinucleotides contribute to many ocular physiological processes. On the ocular surface, dinucleoside polyphosphates can stimulate tear secretion, mucin release from goblet cells and they help epithelial wound healing by accelerating cell migration rate. These dinucleotides can also stimulate the presence of proteins known to protect the ocular surface against microorganisms, such as lysozyme and lactoferrin. One of the latest discoveries is the ability of some dinucleotides to facilitate the paracellular way on the cornea, therefore allowing the delivery of compounds, such as antiglaucomatous ones, more easily within the eye. The compound Ap4A has been described being abnormally elevated in patient's tears suffering of dry eye, Sjogren syndrome, congenital aniridia, or after refractive surgery, suggesting this molecule as biomarker for dry eye condition. At the intraocular level, some diadenosine polyphosphates are abnormally elevated in glaucoma patients, and this can be related to the stimulation of a P2Y2receptor that increases the chloride efflux and water movement in the ciliary epithelium. In the retina, the dinucleotide dCp4U, has been proven to be useful to help in the recovery of retinal detachments. Altogether, dinucleoside polyphosphates are a group of compounds which present relevant physiological actions but which also can perform promising therapeutic benefits.
authors.affiliation: Department of Optics II (Optometry and Vision), Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Carracedo
authors.affiliation: Department of Biochemistry and Molecular Biology IV, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Almudena
authors.initials: A
authors.lastname: Crooke
authors.affiliation: Department of Biochemistry and Molecular Biology IV, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Guzman-Aranguez
authors.affiliation: Department of Biochemistry and Molecular Biology IV, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Pérez de Lara
authors.affiliation: Department of Biochemistry and Molecular Biology IV, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Alba
authors.initials: A
authors.lastname: Martin-Gil
authors.affiliation: Department of Biochemistry and Molecular Biology IV, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain. Electronic address: jpintor@ucm.es.
authors.forename: Jesús
authors.initials: J
authors.lastname: Pintor
mesh_terms: D000818:Animals; D001082:Aqueous Humor / Q000378:metabolism*; D003315:Cornea / Q000378:metabolism*; D015226:Dinucleoside Phosphates / Q000502:physiology*; D006801:Humans; D015290:Second Messenger Systems; D013666:Tears / Q000737:chemistry*; D014018:Tissue Distribution / Q000502:physiology*
chemical_list: D015226:Dinucleoside Phosphates; C020733:diadenosine tetraphosphate
keywords: Diadenosine tetraphosphate; Dinucleotides; Diquafosol; Purinergic receptors