Poklukar Klavdija, Erbežnik Anja, Fazarinc Gregor, Kress Kevin, Batorek-Lukač Nina, Škrlep Martin, Stefanski Volker, Čandek-Potokar Marjeta, Vrecl Milka
Agricultural Institute of Slovenia (KIS), Hacquetova ulica 17, SI-1000, Ljubljana, Slovenia.
Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbičeva ulica 60, SI-1000, Ljubljana, Slovenia.
Vet Anim Sci. 2024 Jul 26;25:100383. doi: 10.1016/j.vas.2024.100383. eCollection 2024 Sep.
This study examined the effects of immunocastration and surgical castration on the histomorphometric and transcriptome traits of the porcine skeletal muscle. We hypothesized that the differences in duration of androgen deprivation resulting from different castration methods influence skeletal muscle biology in a muscle-specific manner. This was tested by analyzing samples of m. longissimus dorsi (LD) and m. semispinalis capitis (SSC) from immunocastrated (IC; = 12), entire male (EM; = 12), and surgically castrated (SC; = 12) pigs using enzyme/immunohistochemical classification and histomorphometric analysis of myofibers, quantitative PCR, and RNA sequencing. The results confirmed the distinctive histomorphometric profiles of LD and SSC and the castration method related muscle-specific effects at the histomorphometric and transcriptome levels. Long-term androgen deficiency (surgical castration) significantly reduced the proportion of fast-twitch type IIa myofibers in LD ( ), whereas short-term androgen deprivation (immunocastration) reduced the cross-sectional area of oxidative type I myofibers in SSC ( ). At the transcriptional level, glycolytic LD adapted to long- and short-term androgen deprivation by upregulating genes controlling myoblast proliferation and differentiation to maintain fiber size. In contrast, increased protein degradation through the ubiquitin ligase-mediated atrophy pathway (significantly increased and expression; ) could underly reduced cross-sectional area of type I myofibers in the oxidative SSC in IC. Potential candidate genes (, and ) linked to specific metabolic profiles and meat quality traits were also identified in IC, providing a foundation for studying the effects of immunocastration on skeletal muscle fiber and carcass/meat quality traits.
本研究考察了免疫去势和手术去势对猪骨骼肌组织形态计量学和转录组特征的影响。我们假设，不同去势方法导致的雄激素剥夺持续时间差异以肌肉特异性方式影响骨骼肌生物学。通过对免疫去势（IC；n = 12）、完整雄性（EM；n = 12）和手术去势（SC；n = 12）猪的背最长肌（LD）和头半棘肌（SSC）样本进行酶/免疫组织化学分类、肌纤维组织形态计量学分析、定量PCR和RNA测序来验证这一假设。结果证实了LD和SSC独特的组织形态计量学特征，以及去势方法在组织形态计量学和转录组水平上对肌肉的特异性影响。长期雄激素缺乏（手术去势）显著降低了LD中快肌IIa型肌纤维的比例（P < 0.05），而短期雄激素剥夺（免疫去势）则降低了SSC中氧化型I型肌纤维的横截面积（P < 0.05）。在转录水平上，糖酵解型LD通过上调控制成肌细胞增殖和分化的基因来适应长期和短期雄激素剥夺，以维持纤维大小。相比之下，通过泛素连接酶介导的萎缩途径增加蛋白质降解（显著增加MAFbx和MuRF1表达；P < 0.05）可能是IC中氧化型SSC中I型肌纤维横截面积减小的原因。在IC中还鉴定出了与特定代谢谱和肉质性状相关的潜在候选基因（MyoD、MyoG和MRF4），为研究免疫去势对骨骼肌纤维及胴体/肉质性状的影响提供了基础。
