Human breast milk concentration of neopterin at various stages of lactation and during a single feeding

Abstract

<jats:title>Abstract</jats:title><jats:p>The aim of this work was to determine the physiological level of neopterin in human breast milk, and to study its variability depending on the duration of a single feeding and the lactation stage. Breast milk samples from 74 women were collected between 2 and 4 days after delivery, and at 15, 30, and 90 days after delivery. Additionally, breast milk samples from eight women were collected before and after 7 and 15 min of breastfeeding. The concentration of neopterin in breast milk was determined by an immunoenzymatic assay. The range of breast milk neopterin concentration at various stages of lactation amounted to 15.4–19.2 nmol/L at 2–4 days after delivery, 20.2–23.0 nmol/L at day 15, 20.8–24.5 nmol/L at day 30, and 16.9–20.4 nmol/L at day 90. The level of neopterin 2–4 days after delivery was significantly lower than that at days 15 and 30; moreover, the concentration of neopterin at day 30 was significantly higher than that at day 90. No significant differences were documented between neopterin concentrations at various phases of a single feeding. While the breast milk concentration of neopterin changes depending on the stage of lactation, it remains stable throughout a single feeding.</jats:p>

Verification studies of tryptophan and kynurenine determination using HPLC and evaluation of the kynurenine pathway and neopterin levels in human colostrum samples

“…In the present study, neopterin levels in colostrum samples ranged from 13.9 to 47.4 nmol/L, with a mean of 28.9 ± 2.6 nmol/L. These neopterin results were consistent with previous studies (Araujo, 2009;O'Rourke et al, 2018;Plata-Nazar et al, 2015).…”

“…T A B L E 3 Recovery data for the colostrum analysis. related to the pregnancy-birth processes (Plata-Nazar et al, 2015).…”

“…Within the scope of our study, the concentrations of neopterin were also detected. Neopterin levels were determined in biological fluids, including blood, urine, cerebrospinal fluid (Molero‐Luis et al, 2020), tears (Baydar et al, 2016), synovial fluid (Zhou et al, 2013), pancreatic juice (Tilg et al, 1992), saliva (Mahendra et al, 2014), ascites (Haeger et al, 1996), and breast milk (Plata‐Nazar et al, 2015). Immediately after birth, the blood concentration of neopterin rises, similar to that observed in the third trimester, and then, it gradually decreases to pre‐pregnancy levels at about the 6th week.…”

“…Colostrum is produced in modest quantities and is high in leukocytes, protein, human milk oligosaccharides, and bioactive factors such as immunoglobulin A (IgA), lactoferrin, epidermal growth factor, transforming growth factor‐beta, colony‐stimulating growth factor, and antioxidants (Ballard & Morrow, 2013). As breast milk is one of the well‐known excretion routes, exposure of the nursing mother to chemical, physical, and biological substances may also mean the possible intake of the same exobiotics through human milk as well as endogenous nutrients and components of passive immunity (Plata‐Nazar et al, 2015).…”

“…Neopterin synthesis is also induced by tumor necrosis factor‐alpha, interleukin 2, granulocytes/monocytes stimulating factor, and lipopolysaccharide. Hence it is used as a sensitive biomarker for detecting and monitoring T helper 1 (Th1)‐type immune activation in humans (Murr et al, 2002; Plata‐Nazar et al, 2015).…”