title: Age-related changes in murine bladder structure and sensory innervation: a multiphoton microscopy quantitative analysis.
abstract: Our study aimed to examine and quantify age-related structural alterations in the healthy mouse bladder using ex vivo two-photon laser scanning microscopy (TPLSM). Freshly dissected bladders from 25-, 52-, and 85-week-old C57bl/6J mice were examined, and morphological analyses and quantification of cell layers and nerves were performed. The numbers of stretched, curled, branched, and total number of nerves in volume units of the stained muscle layer were quantified. We observed differences in the bladder wall architecture and innervation with age. Especially in 85-week-old mice, age-related changes were found, including detachment of urothelial cells and an increase in connective tissue, intermingled with the smooth muscle fibers in the muscle layer (collagen-smooth muscle ratio of 1.15 ± 0.29). In 25- and 52-week-old mice, the collagen-smooth muscle ratios were 0.20 ± 0.04 and 0.31 ± 0.11, respectively, and a clear separation of collagen and muscle was observed. The overall number of nerves and the number of curled nerves were significantly higher in the 85-week-old mice (74.0 ± 13.0 and 25.9 ± 4.8, respectively), when comparing to 25-week-old mice (26.0 ± 2.7 and 6.7 ± 1.2, respectively) and 52-week-old mice (43.8 ± 4.3 and 22.1 ± 3.3, respectively). Significant age-related alterations in bladder morphology and innervation were found, when comparing freshly dissected bladder tissue from 25-, 52-, and 85-week-old mice. The higher number of curled nerves might be an indication of an increased neurotransmitter release, resulting in a higher nerve activity, with a part of the nerves being possibly mechanically impaired. This study shows that two-photon laser scanning microscopy of healthy aging male mice is a useful method to investigate and quantify the age-related changes in the bladder wall.
authors.affiliation: Department of Urology, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ, Maastricht, the Netherlands. anna.schueth@maastrichtuniversity.nl.|School for Mental Health and Neuroscience (MHeNS), Maastricht University, P.O. Box 616, 6200 MD, Maastricht, the Netherlands. anna.schueth@maastrichtuniversity.nl.
authors.forename: Anna
authors.initials: A
authors.lastname: Schueth
authors.affiliation: Department of Biomedical Engineering School for Cardiovascular Diseases (CARIM), Maastricht University, 6229 ER, Maastricht, the Netherlands.
authors.forename: Bart
authors.initials: B
authors.lastname: Spronck
authors.affiliation: Department of Genetics and Cell Biology - Molecular Cell Biology, School for Cardiovascular Diseases (CARIM), Maastricht University, 6229 ER, Maastricht, the Netherlands.|Institute for Molecular Cardiovascular Research (IMCAR), RWTH University of Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany.
authors.forename: Marc A M J
authors.initials: MA
authors.lastname: van Zandvoort
authors.affiliation: Department of Urology, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ, Maastricht, the Netherlands.|School for Mental Health and Neuroscience (MHeNS), Maastricht University, P.O. Box 616, 6200 MD, Maastricht, the Netherlands.
authors.forename: Gommert A
authors.initials: GA
authors.lastname: van Koeveringe
mesh_terms: D000375:Aging; D000818:Animals; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D036641:Microscopy, Fluorescence, Multiphoton / Q000379:methods*; D009130:Muscle, Smooth / Q000294:innervation / Q000648:ultrastructure*; D011984:Sensory Receptor Cells / Q000648:ultrastructure*; D001743:Urinary Bladder / Q000294:innervation* / Q000648:ultrastructure
keywords: Aging; Mice; Multiphoton microscopy; Sensory innervation; Urinary bladder
references.citation: Nat Rev Neurosci. 2008 Jun;9(6):453-66
references.pmid: 18490916
references.citation: Diagn Cytopathol. 2004 May;30(5):297-300
references.pmid: 15108225
references.citation: J Urol. 2014 Sep;192(3):973-80
references.pmid: 24704014
references.citation: Biomed Res Int. 2014;2014:865463
references.pmid: 24900993
references.citation: J Urol. 1986 Aug;136(2):501-4
references.pmid: 3735523
references.citation: Pflugers Arch. 2000;439(3 Suppl):R135-6
references.pmid: 10653168
references.citation: World J Urol. 2009 Dec;27(6):729-37
references.pmid: 19904542
references.citation: Rev Med Liege. 2014 May-Jun;69(5-6):343-8
references.pmid: 25065243
references.citation: Br J Urol. 1986 Aug;58(4):378-81
references.pmid: 3756405
references.citation: Nat Rev Urol. 2014 Aug;11(8):454-64
references.pmid: 25002201
references.citation: Neurourol Urodyn. 2011 Sep;30(7):1227-41
references.pmid: 21520250
references.citation: Eur Urol. 1997;32 Suppl 1:9-14
references.pmid: 9218937
references.citation: Nihon Rinsho. 2013 Oct;71(10):1720-5
references.pmid: 24261198
references.citation: J Am Geriatr Soc. 2006 Mar;54(3):405-12
references.pmid: 16551306
references.citation: Am J Physiol Regul Integr Comp Physiol. 2000 Apr;278(4):R964-72
references.pmid: 10749785
references.citation: J Urol. 1993 Nov;150(5 Pt 2):1668-80
references.pmid: 8411455
references.citation: Neurourol Urodyn. 2014 Jun;33(5):591-6
references.pmid: 24839258
references.citation: Rev Urol. 2004;6 Suppl 1:S3-7
references.pmid: 16985852
references.citation: J Urol. 1995 Jul;154(1):251-6
references.pmid: 7776441
references.citation: Eur Urol. 2015 Sep;68(3):351-3
references.pmid: 25770481
references.citation: Urologe A. 2004 May;43(5):527-34
references.pmid: 15118823
references.citation: World J Urol. 1998;16 Suppl 1:S10-34
references.pmid: 9775413
references.citation: Neurogastroenterol Motil. 2004 Apr;16 Suppl 1:28-33
references.pmid: 15066001
references.citation: Neuroimage. 2007 Aug 1;37(1):1-7
references.pmid: 17574871
references.citation: Neurourol Urodyn. 2007;26(7):981-4
references.pmid: 17626276
references.citation: Urology. 2013 Jun;81(6):1379.e9-14
references.pmid: 23541227
references.citation: Annu Rev Pharmacol Toxicol. 2015;55:269-87
references.pmid: 25251997
references.citation: Curr Urol Rep. 2013 Oct;14(5):379-85
references.pmid: 23922134
references.citation: Scand J Urol Nephrol. 1995 Mar;29(1):45-9
references.pmid: 7618050
references.citation: J Urol. 2000 Feb;163(2):646-51
references.pmid: 10647702
references.citation: Am J Physiol. 1998 Nov;275(5 Pt 2):R1654-60
references.pmid: 9791087
references.citation: J Physiol. 2014 Feb 1;592(3):537-49
references.pmid: 24297847
references.citation: Am J Physiol. 1997 Jul;273(1 Pt 2):F67-75
references.pmid: 9249593
references.citation: Age Ageing. 2014 Mar;43(2):157-63
references.pmid: 24509954