title: Detrusor myocyte autophagy protects the bladder function via inhibiting the inflammation in cyclophosphamide-induced cystitis in rats.
abstract: Autophagy, a highly conserved homeostatic cellular process that removes and recycles damaged proteins and organelles in response to cellular stress, is believed to play a crucial role in the immune response and inflammation. The role of autophagy in bladder cystitis, however, has not well been clarified. Here we investigate the role of detrusor myocytes autophagy (DMA) in cyclophosphamide-induced cystitis animal model. 164 female Sprague-Dawley rats were randomized into three experimental groups and compared to three control groups, respectively. The expressions of microtubule-associated protein 1 light chain 3 (LC3), p-p70s6k (the phosphorylated form of ribosomal protein S6), SOD2 (superoxide dismutase 2) in the bladder muscular layer were measured using western blot. The co-location of LC3, alpha-smooth muscle actin (α-SMA), and autophagic vacuoles were investigated with double-labeled immunofluorescence and transmission electron microscopy (TEM). The expression of lL-1β, IL-6, IL-8, malondialdehyde (MDA), and glutathione (GSH) in the detrusor layer were analyzed using ELISA. The bladder inflammation and the number of mast cells in the muscular layer were analyzed by histology. The bladder function was evaluated using cystometry. In cyclophosphamide-induced cystitis, autophagy was detected in detrusor myocytes by increased LC3, p-p70s6k expression, and autophagosomes. However, the presence of enhanced inflammation and oxidative stress in the cyclophosphamide-treated group suggest autophagy of detrusor myocytes may not be sufficiently activated. Inflammation and oxidative stress were significantly decreased and the bladder histology and micturition function were significantly improved with rapamycin (RAPA, autophagy agonist) pre-treatment. In contrast, inflammation and oxidative stress were dramatically increased and the bladder histology and function were negatively affected with chloroquine (CQ, autophagy blocker) pre-treated. These findings preferentially provide evidence of the association between DMA and cyclophosphamide-induced cystitis in rats. The autophagy agonist RAPA significantly decreased the inflammation and protected the bladder function, which might be considered as a potential treatment for interstitial cystitis.
authors.affiliation: Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Jiang
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Department of Biomedical Engineering, the Cleveland Clinic, Cleveland, OH, United States of America.
authors.forename: Qixiang
authors.initials: Q
authors.lastname: Song
authors.affiliation: Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Xingyou
authors.initials: X
authors.lastname: Dong
authors.affiliation: Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Xingliang
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Xinyu
authors.initials: X
authors.lastname: Bai
authors.affiliation: Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Song
authors.affiliation: Department of Biomedical Engineering, the Cleveland Clinic, Cleveland, OH, United States of America.
authors.forename: Margot
authors.initials: M
authors.lastname: Damaser
authors.affiliation: Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Longkun
authors.initials: L
authors.lastname: Li
mesh_terms: D000818:Animals; D001343:Autophagy; D003520:Cyclophosphamide; D003556:Cystitis / Q000139:chemically induced / Q000276:immunology* / Q000378:metabolism; D005260:Female; D005978:Glutathione / Q000378:metabolism; D007378:Interleukins / Q000378:metabolism; D008315:Malondialdehyde / Q000378:metabolism; D009130:Muscle, Smooth / Q000473:pathology; D032389:Myocytes, Smooth Muscle / Q000502:physiology*; D009929:Organ Size; D017207:Rats, Sprague-Dawley; D013482:Superoxide Dismutase / Q000378:metabolism; D001743:Urinary Bladder / Q000276:immunology / Q000473:pathology / Q000503:physiopathology; D000099156:Superoxide Dismutase 2
chemical_list: D003520:Cyclophosphamide; D005978:Glutathione; D007378:Interleukins; D008315:Malondialdehyde; D013482:Superoxide Dismutase; D000099156:Superoxide Dismutase 2
references.citation: Urology. 2011 Dec;78(6):1443.e1-6
references.pmid: 22000930
references.citation: J Urol. 2006 Feb;175(2):760-5
references.pmid: 16407046
references.citation: J Urol. 2010 Jan;183(1):167-72
references.pmid: 19913812
references.citation: Microbes Infect. 2012 Feb;14(2):119-25
references.pmid: 21924374
references.citation: Front Neurosci. 2011 Feb 22;5:20
references.pmid: 21373362
references.citation: J Urol. 2008 Jun;179(6):2440-6
references.pmid: 18433785
references.citation: Am J Physiol Cell Physiol. 2007 Nov;293(5):C1627-35
references.pmid: 17855776
references.citation: Nat Immunol. 2005 Feb;6(2):135-42
references.pmid: 15662442
references.citation: J Physiol Pharmacol. 2010 Aug;61(4):477-82
references.pmid: 20814076
references.citation: Urology. 2006 Jan;67(1):214-9
references.pmid: 16413378
references.citation: Maturitas. 2009 Dec 20;64(4):212-7
references.pmid: 19837525
references.citation: Nature. 2008 Nov 13;456(7219):264-8
references.pmid: 18849965
references.citation: J Urol. 2013 Mar;189(3):1123-9
references.pmid: 23000860
references.citation: Eur Urol. 2012 Feb;61(2):271-9
references.pmid: 22050826
references.citation: Am J Pathol. 2013 Aug;183(2):626-37
references.pmid: 23770348
references.citation: Neurobiol Dis. 2008 Oct;32(1):16-25
references.pmid: 18640276
references.citation: Cell Death Differ. 2009 Aug;16(8):1093-107
references.pmid: 19373242
references.citation: Proc Natl Acad Sci U S A. 2009 Feb 24;106(8):2770-5
references.pmid: 19196953
references.citation: Eur Urol. 2009 Jul;56(1):159-66
references.pmid: 18514386
references.citation: Cell. 2009 Jun 12;137(6):1001-4
references.pmid: 19524504
references.citation: J Urol. 2011 Aug;186(2):540-4
references.pmid: 21683389
references.citation: Urology. 2007 Apr;69(4 Suppl):34-40
references.pmid: 17462477
references.citation: Ann Rheum Dis. 2012 Apr;71(4):575-81
references.pmid: 22084394
references.citation: Am J Pathol. 2010 Mar;176(3):1181-92
references.pmid: 20075199
references.citation: Autophagy. 2012 Apr;8(4):445-544
references.pmid: 22966490
references.citation: PLoS One. 2014;9(4):e93257
references.pmid: 24695574
references.citation: Urology. 2013 Sep;82(3):743.e9 -15
references.pmid: 23876578
references.citation: Semin Immunol. 2009 Jun;21(3):156-63
references.pmid: 19237300
references.citation: J Soc Gynecol Investig. 2002 Jan-Feb;9(1):15-21
references.pmid: 11839503
references.citation: Nature. 2011 Jan 20;469(7330):323-35
references.pmid: 21248839
references.citation: Am J Physiol Lung Cell Mol Physiol. 2012 Feb 15;302(4):L420-8
references.pmid: 22160308
references.citation: J Clin Invest. 2007 Feb;117(2):326-36
references.pmid: 17235397
references.citation: Neurobiol Dis. 2007 Apr;26(1):86-93
references.pmid: 17270455