RESUMEN
Donkeys of the Pêga breed (Equus asinus) have been used for two centuries to produce breeding stock and create hybrids for labor and transport in southeast Brazil, and for exporting meat and milk to other countries. Furthermore, they are used in competitions, as they are docile and easy to handle. However, assisted reproduction success rates for frozen donkey semen are remarkably low, with no standardized method for cryopreserving sperm after removal of seminal plasma. This work aims to reveal the biological involvement of seminal plasma proteins from Pêga donkeys in aiding the development of assisted reproduction. This study was carried out with 14 ejaculates collected every eight days, throughout the breeding season, from three healthy fertile Pêga donkeys, with an average age of four years. After confirming the high freezability of fresh semen by evaluating quality parameters, the seminal plasma was separated by centrifugation and an aliquot from each collection was microfiltered and frozen. A label-free technique followed by LC-MS/MS analysis applied to pools of seminal plasma samples from each animal revealed 522 proteins in the proteomic profile, of which 49.8 % (260 proteins) are related to cellular energy transformation, and many proteins involved in reproduction (76), spermatogenesis (38), fertilization (29), among other biological process. By comparison with literature, Pêga donkeys share many proteins with donkeys of Dezhou breed that present great potential as fertility biomarkers. Our results showed proteins positively related to fertilization for different breeds of donkeys around the world, helping to enhance the assisted reproduction of Pêga donkeys.
RESUMEN
BACKGROUND: The Mayaro virus (MAYV) is an endemic arbovirus in South American countries, where it is responsible for sporadic outbreaks of Mayaro fever. Clinical manifestations include fever, headache, ocular pain, rash, myalgia, and debilitating and persistent polyarthralgia. Understanding the mechanisms associated with MAYV-induced arthritis is of great importance due to the potential for its emergence, urbanization and dispersion to other regions. METHODS: 15-day old Balb/c mice were infected by two distinct pathways, below the forelimb and in the rear footpad. Animals were observed for a period of 21 days. During this time, they were monitored every 24 hours for disease signs, such as weight loss and muscle weakness. Histological damage in the muscles and joints was evaluated 3, 7, 10, 15 and 20 days post-infection. The cytokine profile in serum and muscles during MAYV infection was evaluated by flow cytometry at different post-infection times. For pain analysis, the animals were submitted to the von Frey test and titre in different organs was evaluated throughout the study to obtain viral kinetics. FINDINGS: Infection by two distinct pathways, below the forelimb and in the rear footpad, resulted in a homogeneous viral spread and the development of acute disease in animals. Clinical signs were observed such as ruffled fur, hunched posture, eye irritation and slight gait alteration. In the physical test, both groups presented loss of resistance, which was associated with histopathological damage, including myositis, arthritis, tenosynovitis and periostitis. The immune response was characterized by a strong inflammatory response mediated by the cytokines TNF-α, IL-6 and INF-γ and chemokine MCP-1, followed by the action of IL-10 and IL-4 cytokines. INTERPRETATION: The results showed that Balb/c mice represent a promising model to study mechanisms involved in MAYV pathogenesis and for future antiviral testing.
