Matthew J Woodman, Matthew A Thomas, Marshall J Colville, Sushmitha Durgam, Sean P McDonough, Heidi L Reesink
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引用次数: 0
Abstract
Objective: To describe proteoglycan 4 (PRG4) expression, lubricin tissue distribution, and lubricin synovial fluid concentrations in healthy and injured equine flexor tendons and tenosynovial structures.
Methods: Synovial fluid and tissues were collected over the span of 1 year. Proteoglycan 4 expression was quantified using quantitative real-time PCR, lubricin synovial fluid concentrations were measured using ELISAs, and lubricin tissue distribution was evaluated with immunohistochemistry. Histology and quantitative real-time PCR data for healthy samples were analyzed using paired t tests, repeated-measures ANOVA, or nonparametric equivalents, and ELISA data for healthy and injured horses were evaluated using mixed linear models.
Results: Samples were obtained from 16 horses without tendon injury and 11 horses with tendon injury (n = 27 horses total). Proteoglycan 4 was expressed in equine superficial digital flexor tendon, deep digital flexor tendon, manica flexoria, and tendon sheath synovial membrane tissues, with the greatest expression in the synovial membrane and manica flexoria.
Conclusions: Lubricin immunohistochemical staining was similar between the healthy superficial digital flexor tendon and deep digital flexor tendon, with more intense staining in epitenon regions and intrasynovial locations. Synovial fluid lubricin concentrations were greater in sheaths with tendon injury (839.4 vs 184.7 µg/mL), and lubricin staining was greater at sites of tendon injury.
Clinical relevance: Lubricin/PRG4 is present in equine flexor tendons and tendon sheaths, with more intense immunostaining in intrasynovial locations and at sites of tendon injury as a possible reparative response to maintain tendon elasticity and gliding function.
目的：探讨蛋白多糖4 （PRG4）在健康和受伤马屈肌腱和肌腱滑膜结构中的表达、润滑素组织分布和润滑素滑膜液浓度。方法：在1年的时间里收集滑液和组织。采用实时荧光定量PCR法测定蛋白多糖4的表达，elisa法测定滑液中润滑素的浓度，免疫组织化学法测定润滑素在组织中的分布。使用配对t检验、重复测量方差分析或非参数等效分析健康样本的组织学和定量实时PCR数据，使用混合线性模型评估健康和受伤马的ELISA数据。结果：从16匹无肌腱损伤的马和11匹肌腱损伤的马（共27匹马）中获得样本。蛋白多糖4在马指屈肌腱浅、指屈肌腱深、屈曲肌腱和肌腱鞘滑膜组织中均有表达，其中在滑膜和屈曲肌腱中表达量最大。结论：润滑素免疫组化染色在正常的指浅屈肌腱和指深屈肌腱之间相似，在表肌腱区和滑膜内部位染色更强烈。滑液润滑素浓度在肌腱损伤的鞘中较高（839.4µg/mL vs 184.7µg/mL），并且润滑素染色在肌腱损伤部位较高。临床意义：润滑素/PRG4存在于马屈肌腱和肌腱鞘中，在腱鞘内和肌腱损伤部位有更强的免疫染色，可能是维持肌腱弹性和滑动功能的修复反应。
期刊介绍：
The American Journal of Veterinary Research supports the collaborative exchange of information between researchers and clinicians by publishing novel research findings that bridge the gulf between basic research and clinical practice or that help to translate laboratory research and preclinical studies to the development of clinical trials and clinical practice. The journal welcomes submission of high-quality original studies and review articles in a wide range of scientific fields, including anatomy, anesthesiology, animal welfare, behavior, epidemiology, genetics, heredity, infectious disease, molecular biology, oncology, pharmacology, pathogenic mechanisms, physiology, surgery, theriogenology, toxicology, and vaccinology. Species of interest include production animals, companion animals, equids, exotic animals, birds, reptiles, and wild and marine animals. Reports of laboratory animal studies and studies involving the use of animals as experimental models of human diseases are considered only when the study results are of demonstrable benefit to the species used in the research or to another species of veterinary interest. Other fields of interest or animals species are not necessarily excluded from consideration, but such reports must focus on novel research findings. Submitted papers must make an original and substantial contribution to the veterinary medicine knowledge base; preliminary studies are not appropriate.
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