title: Increased vitamin D receptor expression in dorsal root ganglia neurons of diabetic rats.
abstract: The effects of vitamin D on the nervous system have been studied extensively. In spite of accumulating data about the substantial changes in the vitamin D receptor (VDR) signaling system, during different types of neuroinflammatory diseases, its role in diabetic neuropathy has not been investigated in detail. To assess the role of VDR signaling in diabetic neuropathy, we examined expression of VDRs in dorsal root ganglia (DRG) neurons in a rat model of streptozotocin-induced diabetes mellitus type 1. Diabetes mellitus (DM) type 1 was induced with streptozotocin in male Sprague-Dawley rats. After two months, expression of VDRs was analyzed immunohistochemically in the cytoplasm of L4 and L5 DRG neurons of diabetic rats. Semi-quantitative analysis for the determination of staining in nuclei and plasma-membranes of DRG neurons was performed. A significant increase in VDR expression was observed in DRG neurons of diabetic rats. Expression of VDRs was increased in the cytoplasm, nuclei and in cell membranes of neurons. An increase in VDR expression occurred in all neurons, but the greatest increase of fluorescence intensity in cytoplasm was observed in neurons of small diameter. Results of the present study indicate that the VDR signaling system could be a potential therapeutic target for diabetic neuropathy.
authors.affiliation: School of Medicine in Split, Department of Anatomy, Histology and Embriology, Šoltanska 2, 21000 Split, Croatia. natalija.filipovic@mefst.hr
authors.forename: Natalija
authors.initials: N
authors.lastname: Filipović
authors.forename: Lejla
authors.initials: L
authors.lastname: Ferhatović
authors.forename: Ivana
authors.initials: I
authors.lastname: Marelja
authors.forename: Livia
authors.initials: L
authors.lastname: Puljak
authors.forename: Ivica
authors.initials: I
authors.lastname: Grković
mesh_terms: D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D005727:Ganglia, Spinal / Q000166:cytology / Q000378:metabolism*; D008297:Male; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018167:Receptors, Calcitriol / Q000378:metabolism*
chemical_list: D018167:Receptors, Calcitriol
keywords: CNS; DM; DRG; Diabetes mellitus; Dorsal root ganglia; ER; MARRS; PBS; RXR; Rat; STZ; VDR; Vitamin D receptors; central nervous system; diabetes mellitus; dorsal root ganglia; endoplasmatic reticulum; membrane associated, rapid response steroid-binding receptor; phosphate-buffered saline; retinoid-X-receptors; streptozotocin; vitamin D receptor