Proteome profiling of exosomes derived from plasma of heifers with divergent genetic merit for fertility

Abstract

The current study evaluated exosomes isolated from plasma of heifers bred to have high or low fertility through developing extreme diversity in fertility breeding values, however, key animal traits (e.g., body weight, milk production, and percentage of North American genetics) remained similar between the 2 groups. The exosomes were isolated by a combined ultracentrifugation and size exclusion chromatography approach and characterized by their size distribution (nanoparticle tracking analysis), morphology (transmission electron microscopy), and presence of exosomal markers (immunoblotting). In addition, a targeted mass spectrometry approach was used to confirm the presence of 2 exosomal markers, tumor susceptibility gene 101 and flotillin 1. The number of exosomes from plasma of high fertility heifers was greater compared with low fertility heifers. Interestingly, the exosomal proteomic profile, evaluated using mass spectrometry, identified 89 and 116 proteins in the high and low fertility heifers respectively, of which 4 and 31 were unique, respectively. These include proteins associated with specific biological processes and molecular functions of fertility. Most notably, the tetratricopeptide repeat protein 41-related, glycodelin, and kelch-like protein 8 were identified in plasma exosomes unique to the low fertility heifers. These proteins are suggested to play a role in reproduction; however, the role of these proteins in dairy cow reproduction remains to be elucidated. Their identification underscores the potential for proteins within exosomes to provide information on the fertility status and physiological condition of the cow. This may potentially lead to the development of prognostic tools and interventions to improving dairy cow fertility.

Circulating exosomes may identify biomarkers for cows at risk for metabolic dysfunction

“…Their interaction with the targeted cell can directly activate membrane receptors or alter the extracellular environment by releasing their contents into the targeted cell 19 . Circulating exosomes isolated from dairy cows may have potential as indicators of fertility status 20 , uterine diseases 21 , and metabolic diseases 22 , as they carry proteins that are unique to the state of the cow.…”

Predicting the likelihood of conception to first insemination of dairy cows using milk mid-infrared spectroscopy

“…This is because milk fat, protein, and lactose percentages are predicted from MIR spectra (De Marchi et al, 2014). Moreover, it also implies that MIR spectra contain other information related to the fertility status of the animal, which might be further elucidated using metabolomics (Phillips et al, 2018), proteomics (Koh et al, 2018), or genome-wide association studies (Wang and Bovenhuis, 2018;Benedet et al, 2019). In terms of a practical application, these results mean that MIR was of primary importance in prediction of fertility of dairy cows.…”

MicroRNA Milk Exosomes: From Cellular Regulator to Genomic Marker

“…The choice of the characterization protocol relies on sample type, isolation method and the application of isolated exososmes. In the case of bovines, different exosomes-containing body fluids have been deeply analyzed, including colostrum and milk [ 78 , 79 , 80 , 81 , 82 ], serum and plasma [ 78 , 83 , 84 , 85 , 86 , 87 , 88 ], urine [ 78 , 89 ], and saliva [ 78 ].Through comparative studies of different bovine biological fluids, a recent study reported that plasma and milk collected from cows have a significantly higher abundance of EXO, in comparison to their urine and saliva [ 78 ].…”