title: Optimizing a Male Reproductive Aging Mouse Model by D-Galactose Injection.
abstract: The d-galactose (d-gal)-injected animal model, which is typically established by administering consecutive subcutaneous d-gal injections to animals for approximately six or eight weeks, has been frequently used for aging research. In addition, this animal model has been demonstrated to accelerate aging in the brain, kidneys, liver and blood cells. However, studies on aging in male reproductive organs that have used this animal model remain few. Therefore, the current study aimed to optimize a model of male reproductive aging by administering d-gal injections to male mice and to determine the possible mechanism expediting senescence processes during spermatogenesis. In this study, C57Bl/6 mice were randomized into five groups (each containing 8-10 mice according to the daily intraperitoneal injection of vehicle control or 100 or 200 mg/kg dosages of d-gal for a period of six or eight weeks). First, mice subjected to d-gal injections for six or eight weeks demonstrated considerably decreased superoxide dismutase activity in the serum and testis lysates compared to those in the control group. The lipid peroxidation in testis also increased in the d-gal-injected groups. Furthermore, the d-gal-injected groups exhibited a decreased ratio of testis weight/body weight and sperm count compared to the control group. The percentages of both immotile sperm and abnormal sperm increased considerably in the d-gal-injected groups compared to those of the control group. To determine the genes influenced by the d-gal injection during murine spermatogenesis, a c-DNA microarray was conducted to compare testicular RNA samples between the treated groups and the control group. The d-gal-injected groups exhibited RNA transcripts of nine spermatogenesis-related genes (Cycl2, Hk1, Pltp, Utp3, Cabyr, Zpbp2, Speer2, Csnka2ip and Katnb1) that were up- or down-regulated by at least two-fold compared to the control group. Several of these genes are critical for forming sperm-head morphologies or maintaining nuclear integration (e.g., cylicin, basic protein of sperm head cytoskeleton 2 (Cylc2), casein kinase 2, alpha prime interacting protein (Csnka2ip) and katanin p80 (WD40-containing) subunit B1 (Katnb1)). These results indicate that d-gal-injected mice are suitable for investigating male reproductive aging.
authors.affiliation: PhD Program in Nutrition &amp; Food Science, Fu Jen Catholic University, No. 510, Zhongzheng Road, Xinzhuang District, New Taipei City 242, Taiwan. liaoch22@gmail.com.|Division of Urology, Department of Surgery, Cardinal Tien Hospital, No. 362, Zhongzheng Road, Xindian District, New Taipei City 231, Taiwan. liaoch22@gmail.com.|School of Medicine, Fu Jen Catholic University, No. 510, Zhongzheng Road, Xinzhuang District, New Taipei City 242, Taiwan. liaoch22@gmail.com.
authors.forename: Chun-Hou
authors.initials: CH
authors.lastname: Liao
authors.affiliation: Department of Food Science, Fu Jen Catholic University, No. 510, Zhongzheng Road, Xinzhuang District, New Taipei City 242, Taiwan. 002622@mail.fju.edu.tw.
authors.forename: Bing-Huei
authors.initials: BH
authors.lastname: Chen
authors.affiliation: School of Medicine, Fu Jen Catholic University, No. 510, Zhongzheng Road, Xinzhuang District, New Taipei City 242, Taiwan. 053824@mail.fju.edu.tw.|Graduate Institute of Basic Medicine, Fu Jen Catholic University, No. 510, Zhongzheng Road, Xinzhuang District, New Taipei City 242, Taiwan. 053824@mail.fju.edu.tw.
authors.forename: Han-Sun
authors.initials: HS
authors.lastname: Chiang
authors.affiliation: Graduate Institute of Basic Medicine, Fu Jen Catholic University, No. 510, Zhongzheng Road, Xinzhuang District, New Taipei City 242, Taiwan. okwapnice@hotmail.com.
authors.forename: Chiu-Wei
authors.initials: CW
authors.lastname: Chen
authors.affiliation: Research Center for Emerging Viral Infections, Chang Gung University, No. 259 Wen-Hwa 1st Road, Kwei-Shan Taoyuan 333, Taiwan. mfchen0@gmail.com.
authors.forename: Mei-Feng
authors.initials: MF
authors.lastname: Chen
authors.affiliation: Department of Urology, En Chu Kong Hospital, No. 399, Fuxing Road, Sanxia District, New Taipei City 237, Taiwan. koacurtis@gmail.com.
authors.forename: Chih-Chun
authors.initials: CC
authors.lastname: Ke
authors.affiliation: Department of Chemistry, Fu Jen Catholic University, No. 510, Zhongzheng Road, Xinzhuang District, New Taipei City 242, Taiwan. vic0009@gmail.com.
authors.forename: Ya-Yun
authors.initials: YY
authors.lastname: Wang
authors.affiliation: Graduate Institute of Basic Medicine, Fu Jen Catholic University, No. 510, Zhongzheng Road, Xinzhuang District, New Taipei City 242, Taiwan. 081551@mail.fju.edu.tw.
authors.forename: Wei-Ning
authors.initials: WN
authors.lastname: Lin
authors.affiliation: Graduate Institute of Basic Medicine, Fu Jen Catholic University, No. 510, Zhongzheng Road, Xinzhuang District, New Taipei City 242, Taiwan. 075006@mail.fju.edu.tw.
authors.forename: Chi-Chung
authors.initials: CC
authors.lastname: Wang
authors.affiliation: Graduate Institute of Basic Medicine, Fu Jen Catholic University, No. 510, Zhongzheng Road, Xinzhuang District, New Taipei City 242, Taiwan. 084952@mail.fju.edu.tw.
authors.forename: Ying-Hung
authors.initials: YH
authors.lastname: Lin
mesh_terms: D000375:Aging / Q000187:drug effects*; D000818:Animals; D005690:Galactose / Q000008:administration & dosage / Q000494:pharmacology*; D007274:Injections, Intraperitoneal; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D008810:Mice, Inbred C57BL; D009929:Organ Size / Q000187:drug effects; D012098:Reproduction / Q000187:drug effects*; D013076:Sperm Count; D013091:Spermatogenesis / Q000187:drug effects*; D013482:Superoxide Dismutase / Q000378:metabolism; D013737:Testis / Q000187:drug effects / Q000502:physiology
chemical_list: D013482:Superoxide Dismutase; D005690:Galactose
keywords: aging; male infertility; mouse model