Molecular cloning, functional characterization, tissue expression and polymorphism analysis of buffalo PRDX6 gene

PRDX6 is a bifunctional protein involved in antioxidant regulation and phospholipid metabolism. Previous studies have shown that PRDX6 is involved in some biological pathways and networks related to lactation. The aim of this study was to explore the characteristics, function, tissue expression and variation of buffalo PRDX6 gene. We cloned and characterized the complete coding sequence (CDS) of buffalo PRDX6. The CDS of PRDX6 for swamp and river buffalo is the same, which consists of 675 nucleotides and encodes a protein of 224 amino acids. Buffalo PRDX6 contains one PRX_1cys functional domain (AA 7–222), which is probably related to the regulation of oxidative stress. Multi-tissue differential expression analysis showed that buffalo PRDX6 was highly expressed in the muscle, brain, lung and small intestine during non-lactation and lactation, and there were significant differences in expression in all the tissues except the small intestine between the two periods. It is worth noting that the mRNA abundance of buffalo PRDX6 in non-lactating mammary gland is higher than that in lactating mammary gland. Among the two single nucleotide polymorphisms (SNPs) identified in the CDS in this study, c.261C>T is shared by the two types of buffalo with different allelic frequencies, and c.426T>G is found only in river buffalo. The c.426T>G is non-synonymous, resulting in the amino acid substitution p.Asn142Lys. Only one nucleotide differential site is identified in PRDX6 gene between buffalo and other species of Bovidae. Phylogenetic analysis indicated that buffalo PRDX6 has a closer genetic relationship with that of the species in Bovidae. These results indicate that PRDX6 probably plays a crucial role in the mammary gland of buffalo. This study provides the foundation for further functional studies of PRDX6 in buffalo.

Molecular cloning, functional characterization, tissue expression and polymorphism analysis of buffalo PRDX6 gene

PRDX6 is a bifunctional protein involved in antioxidant regulation and phospholipid metabolism. Previous studies have shown that PRDX6 is involved in some biological pathways and networks related to lactation. The aim of this study was to explore the characteristics, function, tissue expression and variation of buffalo PRDX6 gene. We cloned and characterized the complete coding sequence (CDS) of buffalo PRDX6. The CDS of PRDX6 for swamp and river buffalo is the same, which consists of 675 nucleotides and encodes a protein of 224 amino acids. Buffalo PRDX6 contains one PRX_1cys functional domain (AA 7–222), which is probably related to the regulation of oxidative stress. Multi-tissue differential expression analysis showed that buffalo PRDX6 was highly expressed in the muscle, brain, lung and small intestine during non-lactation and lactation, and there were significant differences in expression in all the tissues except the small intestine between the two periods. It is worth noting that the mRNA abundance of buffalo PRDX6 in non-lactating mammary gland is higher than that in lactating mammary gland. Among the two single nucleotide polymorphisms (SNPs) identified in the CDS in this study, c.261C>T is shared by the two types of buffalo with different allelic frequencies, and c.426T>G is found only in river buffalo. The c.426T>G is non-synonymous, resulting in the amino acid substitution p.Asn142Lys. Only one nucleotide differential site is identified in PRDX6 gene between buffalo and other species of Bovidae. Phylogenetic analysis indicated that buffalo PRDX6 has a closer genetic relationship with that of the species in Bovidae. These results indicate that PRDX6 probably plays a crucial role in the mammary gland of buffalo. This study provides the foundation for further functional studies of PRDX6 in buffalo.

Association between THRSP Gene Polymorphism and Fatty Acid Composition in Milk of Dairy Cows

Thyroid hormone-inducible hepatic protein is involved in the de novo synthesis of fatty acids in the lactating mammary gland. Different variants of the gene that encodes this protein may be associated with its different activity. The primary aim of this study was to find polymorphism in the THRSP gene and estimate the relationship between individual genotypes and fatty acid composition in milk. Investigations were carried out on 224 cows represented by two breeds—Jersey (n = 80) and Polish Holstein-Friesian (n = 144). Polymorphism in THRSP was detected by Sanger sequencing; however, genotypes were determined by the PCR-RFLP method. It was shown that the analyzed variant had a significant (p < 0.05) influence on palmitic and stearic fatty acids as well as on fatty acids with a chain length of 14, 16, and 6–16 in Jersey breed and on caproic, palmitic, myristoleic, and palmitoleic fatty acids in H-F. Obtained results indicated that analyzed SNP in bovine THRSP gene (rs42714482) may be considered as a potential marker for fatty acid composition in milk

“Mother-Microbe-Infant-Microbe” Synchrony– A Mini Review

Is breast milk nutrition “alive”, dynamic and impossible to emulate? This question remains important in the context of the emergence of novel diseases and may be answered by comparing it to a few events that happen in nature, with parallels evident in the breast feeding dyad. Edified by nature, and its myriad coexisting species, including the microbes, there seems to be much interplay between species through symbiosis, perhaps, with a lofty purpose. This is compared to the breastfeeding infant’s gut that develops in symbiosis with the microbes that enter it through every feed. Breast milk not only nurtures the infant, but also nourishes the commensal microbes it provides. Milk microbes are influenced by maternal, infant and environmental variables, supporting them differently, parallel to the manner in which microbes and other elements in nature support ecosystems. Reviewing and synthesising information from two different but comparable ecosystems show parallels worthy of appraisal. The lactating mammary gland provides and supports beneficial microbes and microbial environments. Secretory immunoglobulin A (sIgA), the key molecule of mucosal gut immunity, is mutualistic with commensal microbes, capable of mucosal defences, yet preserving equilibrium between pathogen defences and commensal tolerance. Through microbial signals, the nursing mother shares her mucosal immune experiences, commenced in utero, transplacentally and then “translactionally”, to mature infant immunity, concluding an exceptional loop of nurture. Technology allows much appreciation that “immune cross- talk” between mother and infant does occur. In this review, commensal gut microbes in the infant are conceptualised as miniature ecosystems and, breastfeeding, as a vibrant compartment where being “alive” pivots in and around microbial existence and sustenance - a biological setting that, at best, may be emulated but not reproduced.

Lactation vs formula feeding: Insulin, glucose and fatty acid metabolism during the postpartum period

Milk production may involve a transient development of insulin resistance in non-mammary tissues to support redistribution of maternal macronutrients to match the requirements of the lactating mammary gland. In the present study, adipose and liver metabolic responses were measured in the fasting state and during a 2-step (10 and 20 mU/m²/min) hyperinsulinemic-euglycemic clamp with stable isotopes, in 6-week postpartum women who were lactating (n=12) or formula-feeding (n=6) their infants and who were closely matched for baseline characteristics (e.g., parity, body composition, intrahepatic lipid). When controlling for the low insulin concentrations of both groups, the lactating women exhibited a fasting rate of endogenous glucose production (EGP) that was 2.6-fold greater, and a lipolysis rate that was 2.3-fold greater than the formula-feeding group. During the clamp, the groups exhibited similar suppression rates of EGP and lipolysis. In the lactating women only, higher prolactin concentrations were associated with greater suppression rates of lipolysis, lower intrahepatic lipid and plasma triacylglycerol concentrations. These data suggest that whole-body alterations in glucose transport may be organ specific and facilitate nutrient partitioning during lactation. Recapitulating a shift toward noninsulin-mediated glucose uptake could be an early postpartum strategy to enhance lactation success in women at risk for delayed onset of milk production. <br>

Lactation vs formula feeding: Insulin, glucose and fatty acid metabolism during the postpartum period

Milk production may involve a transient development of insulin resistance in non-mammary tissues to support redistribution of maternal macronutrients to match the requirements of the lactating mammary gland. In the present study, adipose and liver metabolic responses were measured in the fasting state and during a 2-step (10 and 20 mU/m²/min) hyperinsulinemic-euglycemic clamp with stable isotopes, in 6-week postpartum women who were lactating (n=12) or formula-feeding (n=6) their infants and who were closely matched for baseline characteristics (e.g., parity, body composition, intrahepatic lipid). When controlling for the low insulin concentrations of both groups, the lactating women exhibited a fasting rate of endogenous glucose production (EGP) that was 2.6-fold greater, and a lipolysis rate that was 2.3-fold greater than the formula-feeding group. During the clamp, the groups exhibited similar suppression rates of EGP and lipolysis. In the lactating women only, higher prolactin concentrations were associated with greater suppression rates of lipolysis, lower intrahepatic lipid and plasma triacylglycerol concentrations. These data suggest that whole-body alterations in glucose transport may be organ specific and facilitate nutrient partitioning during lactation. Recapitulating a shift toward noninsulin-mediated glucose uptake could be an early postpartum strategy to enhance lactation success in women at risk for delayed onset of milk production. <br>

Timing of entry of Streptococcus uberis into the mammary gland of the dairy cow

Streptococcus uberis do not colonise the teat canal and appear to invade the mammary gland of the dairy cow by direct entry though the canal. When they enter the mammary gland, and the early resulting processes, are unclear. Experimental infusions of the lactating mammary gland have been made to determine outcomes of infection, mastitis and disease. Infusion of 500 cfu bacteria was made immediately after milking (8 and 16 h intermilking interval) and 1, 4 or 12 h prior to milking. A mastitis resulted from all infusions, probably in response to the skim milk carrier. Infusions post milking resulted in clinical mastitis in more than half of the quarters, whereas infusion 1 h premilking created no clinical mastitis. Infusion 4 or 12 h pre milking resulted in the most severe reactions, with all quarters developing moderate to severe clinical mastitis. This was more rapid with the 4 h pre milking group. The results demonstrate that the initial inflammatory response caused by an invasion of the mammary gland is not necessarily protective against establishment of a pathogen, and that especially the response to invasion in the intermilking interval is often insufficient to prevent infection and/or disease.