BACKGROUND: Huntington disease (HD) is a fatal neurodegenerative disorder involving reduced muscle coordination, mental and behavioral changes, and testicular degeneration. In order to further clarify the decreased fertility and penetration ability of the spermatozoa of transgenic HD minipig boars (TgHD), we applied a set of mitochondrial metabolism (MM) parameter measurements to this promising biological material, which can be collected noninvasively in longitudinal studies. OBJECTIVE: We aimed to optimize methods for MM measurements in spermatozoa and to establish possible biomarkers of HD in TgHD spermatozoa expressing the N-terminal part of mutated human huntingtin. METHODS: Semen samples from 12 TgHD and wild-type animals, aged 12-65 months, were obtained repeatedly during the study. Respiration was measured by polarography, MM was assessed by the detection of oxidation of radiolabeled substrates (mitochondrial energy-generating system; MEGS), and the content of the oxidative phosphorylation system subunits was detected by Western blot. Three possibly interfering factors were statistically analyzed: the effect of HD, generation and aging. RESULTS: We found 5 MM parameters which were significantly diminished in TgHD spermatozoa and propose 3 specific MEGS incubations and complex I-dependent respiration as potential biomarkers of HD in TgHD spermatozoa. CONCLUSIONS: Our results suggest a link between the gain of toxic function of mutated huntingtin in TgHD spermatozoa and the observed MM and/or glycolytic impairment. We determined 4 biomarkers useful for HD phenotyping and experimental therapy monitoring studies in TgHD minipigs.
- Klíčová slova
- Huntington disease, Large-animal model, Mitochondrial metabolism, Mutant huntingtin, Spermatozoa,
- MeSH
- dýchání MeSH
- geneticky modifikovaná zvířata MeSH
- Huntingtonova nemoc komplikace genetika patologie MeSH
- kyseliny trikarboxylové metabolismus MeSH
- lidé MeSH
- miniaturní prasata MeSH
- mitochondriální proteiny metabolismus MeSH
- mitochondrie metabolismus MeSH
- mutace genetika MeSH
- oxidativní fosforylace MeSH
- prasata MeSH
- protein huntingtin genetika MeSH
- pyruvátdehydrogenasový komplex metabolismus MeSH
- sperma metabolismus MeSH
- spermie metabolismus patologie MeSH
- trinukleotidové repetice genetika MeSH
- věkové faktory MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- HTT protein, human MeSH Prohlížeč
- kyseliny trikarboxylové MeSH
- mitochondriální proteiny MeSH
- protein huntingtin MeSH
- pyruvátdehydrogenasový komplex MeSH
BACKGROUND: Huntington's disease is induced by CAG expansion in a single gene coding the huntingtin protein. The mutated huntingtin (mtHtt) primarily causes degeneration of neurons in the brain, but it also affects peripheral tissues, including testes. OBJECTIVE: We studied sperm and testes of transgenic boars expressing the N-terminal region of human mtHtt. METHODS: In this study, measures of reproductive parameters and electron microscopy (EM) images of spermatozoa and testes of transgenic (TgHD) and wild-type (WT) boars of F1 (24-48 months old) and F2 (12-36 months old) generations were compared. In addition, immunofluorescence, immunohistochemistry, Western blot, hormonal analysis and whole-genome sequencing were done in order to elucidate the effects of mtHtt. RESULTS: Evidence for fertility failure of both TgHD generations was observed at the age of 13 months. Reproductive parameters declined and progressively worsened with age. EM revealed numerous pathological features in sperm tails and in testicular epithelium from 24- and 36-month-old TgHD boars. Moreover, immunohistochemistry confirmed significantly lower proliferation activity of spermatogonia in transgenic testes. mtHtt was highly expressed in spermatozoa and testes of TgHD boars and localized in all cells of seminiferous tubules. Levels of fertility-related hormones did not differ in TgHD and WT siblings. Genome analysis confirmed that insertion of the lentiviral construct did not interrupt any coding sequence in the pig genome. CONCLUSIONS: The sperm and testicular degeneration of TgHD boars is caused by gain-of-function of the highly expressed mtHtt.
- MeSH
- genetické vektory MeSH
- geneticky modifikovaná zvířata MeSH
- Huntingtonova nemoc metabolismus patologie MeSH
- Lentivirus genetika MeSH
- lidé MeSH
- miniaturní prasata MeSH
- modely nemocí na zvířatech MeSH
- mutace * MeSH
- počet spermií MeSH
- prasata MeSH
- proliferace buněk fyziologie MeSH
- protein huntingtin genetika metabolismus MeSH
- spermie metabolismus patologie MeSH
- stárnutí metabolismus patologie MeSH
- testis metabolismus patologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- HTT protein, human MeSH Prohlížeč
- protein huntingtin MeSH
BACKGROUND: Some promising treatments for Huntington's disease (HD) may require pre-clinical testing in large animals. Minipig is a suitable species because of its large gyrencephalic brain and long lifespan. OBJECTIVE: To generate HD transgenic (TgHD) minipigs encoding huntingtin (HTT)1-548 under the control of human HTT promoter. METHODS: Transgenesis was achieved by lentiviral infection of porcine embryos. PCR assessment of gene transfer, observations of behavior, and postmortem biochemical and immunohistochemical studies were conducted. RESULTS: One copy of the human HTT transgene encoding 124 glutamines integrated into chromosome 1 q24-q25 and successful germ line transmission occurred through successive generations (F0, F1, F2 and F3 generations). No developmental or gross motor deficits were noted up to 40 months of age. Mutant HTT mRNA and protein fragment were detected in brain and peripheral tissues. No aggregate formation in brain up to 16 months was seen by AGERA and filter retardation or by immunostaining. DARPP32 labeling in WT and TgHD minipig neostriatum was patchy. Analysis of 16 month old sibling pairs showed reduced intensity of DARPP32 immunoreactivity in neostriatal TgHD neurons compared to those of WT. Compared to WT, TgHD boars by one year had reduced fertility and fewer spermatozoa per ejaculate. In vitro analysis revealed a significant decline in the number of WT minipig oocytes penetrated by TgHD spermatozoa. CONCLUSIONS: The findings demonstrate successful establishment of a transgenic model of HD in minipig that should be valuable for testing long term safety of HD therapeutics. The emergence of HD-like phenotypes in the TgHD minipigs will require more study.
- Klíčová slova
- AGERA assay, DARPP32, FISH analysis, Huntington's disease, TR-FRET assay, immunohistochemistry, large animal model, lentiviral transgenesis, mRNA and protein expression, minipigs, mutant huntingtin, spermatozoa,
- MeSH
- genetické vektory MeSH
- geneticky modifikovaná zvířata * MeSH
- Huntingtonova nemoc * MeSH
- hybridizace in situ MeSH
- Lentivirus MeSH
- miniaturní prasata MeSH
- modely nemocí na zvířatech * MeSH
- polymerázová řetězová reakce MeSH
- prasata MeSH
- protein huntingtin MeSH
- proteiny nervové tkáně genetika MeSH
- transdukce genetická MeSH
- transgeny MeSH
- western blotting MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- HTT protein, human MeSH Prohlížeč
- protein huntingtin MeSH
- proteiny nervové tkáně MeSH
