The female reproductive tract, in particular the composition of the uterine and oviduct fluids, is responsible, at least in part, for triggering sperm cell modifications, essential for the acquisition of fertilization ability. Hyaluronic acid (HA) is a glycosaminoglycan present in these fluids, and its role in the fertilization process and sperm functionality is still barely understood. This work was designed to (a) determine the rheological characteristics of the fertilization medium by the addition of HA and (b) determine the HA influence on sperm motility and functional status. To that end, the in vitro fertilization medium was supplemented with 4 doses of HA (6, 60, 600 and 6,000 µg/ml) and analysed for viscosity and adhesion strength characteristics. Then, thawed semen from 6 bulls were incubated in these media and assessed at 4 different moments for morphological and functional parameters (plasma and acrosomal membrane integrities, mitochondrial membrane potential, capacitation, acrosomal reaction, and motility). The rheological evaluation showed that the addition of HA was able to increase both the viscosity and the adhesion strength of the fertilization medium, especially in the 6,000 µg/ml group in which the effect was more pronounced. No influence of HA could be observed on mitochondrial potential, and acrosomal and plasma membrane integrities. However, HA supplementation, at lower doses, led to an increase in the number of reacted sperm, as well as changes in motility parameters, with increase in the number of motile, rapid and progressive spermatozoa. In conclusion, the addition of HA alters the rheological properties of the fertilization medium and leads to the improvement of the properties related to sperm motility and capacitation, without compromising other functional aspects of the cell.

中文翻译：

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使用透明质酸改变施肥介质的粘度会影响公牛的精子活力和顶体状态。

女性生殖道，特别是子宫和输卵管液的成分，至少部分负责触发精子细胞的修饰，这对于获得受精能力至关重要。透明质酸（HA）是存在于这些液体中的糖胺聚糖，其在受精过程和精子功能中的作用仍鲜为人知。这项工作旨在（a）通过添加HA确定受精培养基的流变特性，以及（b）确定HA对精子活力和功能状态的影响。为此，在体外受精培养基中补充了4剂HA（6、60、600和6,000 µg / ml），并分析了其粘度和粘附强度特性。然后，将来自6头公牛的解冻精液在这些培养基中孵育，并在4个不同时刻评估其形态和功能参数（血浆和顶体膜完整性，线粒体膜电位，获能，顶体反应和运动性）。流变学评估表明，添加HA能够提高施肥介质的粘度和粘附强度，特别是在6,000 µg / ml组中，效果更明显。没有观察到HA对线粒体电位以及顶体和质膜完整性的影响。但是，低剂量的HA补充会导致反应精子数量的增加，以及运动参数的变化，以及运动，快速和进行性精子数量的增加。结论，