title: Identification of increased amounts of eppin protein complex components in sperm cells of diabetic and obese individuals by difference gel electrophoresis.
abstract: Metabolic disorders like diabetes mellitus and obesity may compromise the fertility of men and women. To unveil disease-associated proteomic changes potentially affecting male fertility, the proteomes of sperm cells from type-1 diabetic, type-2 diabetic, non-diabetic obese and clinically healthy individuals were comparatively analyzed by difference gel electrophoresis. The adaptation of a general protein extraction procedure to the solubilization of proteins from sperm cells allowed for the resolution of 3187 fluorescent spots in the difference gel electrophoresis image of the master gel, which contained the entirety of solubilized sperm proteins. Comparison of the pathological and reference proteomes by applying an average abundance ratio setting of 1.6 and a p ≤ 0.05 criterion resulted in the identification of 79 fluorescent spots containing proteins that were present at significantly changed levels in the sperm cells. Biometric evaluation of the fluorescence data followed by mass spectrometric protein identification revealed altered levels of 12, 71, and 13 protein species in the proteomes of the type-1 diabetic, type-2 diabetic, and non-diabetic obese patients, respectively, with considerably enhanced amounts of the same set of one molecular form of semenogelin-1, one form of clusterin, and two forms of lactotransferrin in each group of pathologic samples. Remarkably, β-galactosidase-1-like protein was the only protein that was detected at decreased levels in all three pathologic situations. The former three proteins are part of the eppin (epididymal proteinase inhibitor) protein complex, which is thought to fulfill fertilization-related functions, such as ejaculate sperm protection, motility regulation and gain of competence for acrosome reaction, whereas the putative role of the latter protein to function as a glycosyl hydrolase during sperm maturation remains to be explored at the protein/enzyme level. The strikingly similar differences detected in the three groups of pathological sperm proteomes reflect a disease-associated enhanced formation of predominantly proteolytically modified forms of three eppin protein complex components, possibly as a response to enduring hyperglycemia and enhanced oxidative stress.
authors.affiliation: University of Leipzig, Medical Faculty, Department of Dermatology, Training Center of the European Academy of Andrology, D-04103 Leipzig, Germany. uwe.paasch@medizin.uni-leipzig.de
authors.forename: Uwe
authors.initials: U
authors.lastname: Paasch
authors.forename: Falk
authors.initials: F
authors.lastname: Heidenreich
authors.forename: Theresia
authors.initials: T
authors.lastname: Pursche
authors.forename: Eberhard
authors.initials: E
authors.lastname: Kuhlisch
authors.forename: Karina
authors.initials: K
authors.lastname: Kettner
authors.forename: Sonja
authors.initials: S
authors.lastname: Grunewald
authors.forename: Jürgen
authors.initials: J
authors.lastname: Kratzsch
authors.forename: Gunnar
authors.initials: G
authors.lastname: Dittmar
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Glander
authors.forename: Bernard
authors.initials: B
authors.lastname: Hoflack
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Kriegel
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D048430:Cell Shape; D051152:Clusterin / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007248:Infertility, Male / Q000209:etiology / Q000378:metabolism / Q000473:pathology*; D007781:Lactoferrin / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D046912:Multiprotein Complexes / Q000378:metabolism; D009765:Obesity / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D020033:Protein Isoforms / Q000378:metabolism; D053491:Proteinase Inhibitory Proteins, Secretory / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism; D012015:Reference Standards; D029607:Seminal Vesicle Secretory Proteins / Q000378:metabolism; D013076:Sperm Count; D013081:Sperm Motility; D013094:Spermatozoa / Q000378:metabolism*; D057825:Two-Dimensional Difference Gel Electrophoresis / Q000592:standards; D055815:Young Adult
chemical_list: D015415:Biomarkers; C495242:CLU protein, human; D051152:Clusterin; C431553:Eppin protein, human; C490098:LTF protein, human; D046912:Multiprotein Complexes; D020033:Protein Isoforms; D053491:Proteinase Inhibitory Proteins, Secretory; D020543:Proteome; D029607:Seminal Vesicle Secretory Proteins; C424482:seminal vesicle-specific antigen; D007781:Lactoferrin