Abstract
The aim of this study was to determine the free amino acid pool in plasma and milk in marginally nourished lactating women. Twenty-eight rural women (age, 23.9 ± 5y; weight 50.2 ± 4.9 kg; height, 148.2 ± 4.8 cm) were studied under metabolic balance conditions. Subjects were divided into 6 groups (5-6 women in each), representing rural mothers postweaning and in the 1st, 3rdand6th months of lactation; nonpregnant, nonlactating controls were from rural and urban areas Amino acid analyses of diet and of plasma and milk samples were performed using a Beckman 6300 amino acid analyzer. Lysine intakes were lower than the recommended intake for lactating women (RDA). Plasma amino acid profiles differed between the lactating and weaned groups: aspartate and isoleucine increased at the 6th month (P < 0.05), while valine declined over weaning time (P < 0.05). In milk, valine and proline decreased at the 6th month (P < 0.05), while serine rose at the 3rd month. Free amino acid pools were 1- to 15-fold higher in plasma than in milk for branched-chain amino acids and basic, aromatic, and neutral amino acids. In mammary tissue these amino acids can be channeled to tissue and milk protein synthesis or to catabolic pathways. Glutamate was 40-fold higher in milk with respect to plasma content. This was the predominant amino acid in the free amino acid pool in milk These results suggest selective amino acid transport in mammary tissue during lactation.
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References
Chavalittamrong B, Suanpan S, Boonvisut S, Chatranon W, Gershoff SN. Protein and amino acids of breast milk from Thai mothers. Am J Clin Nutr 1981;34:1126–1130.
DeSantiago S, González M, Barbosa L, Hernandez-Montes H, Villalpando S. Maternal protein metabolism during lactation and abrupt weaning in the rat. In: Picciano MF, Lonnerdal B, editors. Mechanisms Regulating Lactation and Infant Nutrient Utilization. New York: Wiley-Liss; 1992. pp 373–375.
De Santiago S, Villalpando S, Ortíz-Olaya N, Alonso L, Ramírez-Alvaro I. Protein requirement of marginally nourished lactating women. Am J Clin Nutr 1995;62:364–370.
DeSantiago S, Alemán G, Hernandez-Montes H. Alanine aminotransferase activity in mammary tissue,muscle and liver of dam rat during lactation and weaning. Arch Med Res 1996;27:443–448.
DeSantiago S, Torres N, Tovar AR. Leucine catabolism in mammary tissue, liver and skeletal muscle ofdam rat during lactation and weaning. Arch Med Res 1998;29:25–32.
DeSantiago S, Ramirez 1, Tovar AR, Alonso L, Ortiz-Olaya N, Torres N. Free amino acid plasma and milk of Mexican rural lactating women. Rev Invest Med 1998;50:405–412.
DeSantiago S, Ramirez 1, Tovar AR, Ortiz N, Torres N, Bourges H. Amino acid profiles in diet, plasma and human milk in Mexican lactating women. Nutr Res 1999;19:1133–1143.
Edozien JC, Rahim Khan MA, Waslien CI. Human protein deficiency results of a Nigerian village study. J Nutr 1976;106:312–328.
Forsum E, Lönnerdal B. Effect of protein intake on protein and nitrogen composition of breast milk. Am J Clin Nutr 1980;33:1809–1813.
Harper AE. Amino acid toxicities and imbalances. In: Munro HN, Allison JB, editors. Mammalian Protein Metabolism, vol. 2. New York: Academic Press; 1964. p. 87.
Janas LM, Picciano ME Quantities of amino acids ingested by human milk-fed infants. J Pediatr 1986; 109:802–807.
Lindblad BS, Rahimtoola RJ. A pilot study of the quality of human milk in a lower socio-economic group in Karachi, Pakistan. Acta Pediatr Scand 1974;63:125–128.
Motil T, Barej W. Plasma amino acid indices and urinary 3-methyl histidine excretion in dairy cows in early lactation. Ann Rech Vet 1986;17:153–157.
Motil KJ, Thotathuchery M, Montandon CM, Hachey DL, Boutton TW, Klein PD, Garza C. Insulin, cortisol and thyroid hormones modulate maternal protein status and milk production and composition in humans. J Nutr 1994;124:1248–1257.
Motil KJ, Thotathuchery M, Bahar A, Montandon CM. Marginal dietary protein restriction reduced nonprotein nitrogen, but not protein nitrogen, components of human milk. J Am Coll Nutr 1995;14:184–191.
Rao BSN, Pasricha S, Gopalan C. Nitrogen balance studies in poor Indian women during lactation. Ind J Med Res 1958;46:325–331.
Richardson BC, Mercier JC. The primary structure of the ovine beta-caseins. Eur J Biochem 1979; 99:285–297.
Salmon WD. The significance of amino acid imbalance in nutrition. Am J Clin Nutr 1958;6:487–495. Shennan DB, Millar ID, Calvert DT. Mammary tissue amino acid transport systems. Proc Nutr Soc 1997;56:177–191.
Tovar AR, Ascencio C, Torres N, Gómez E, Bourges H. Neutral and basic amino acid concentrations in plasma during the day in subjects fed with two model rural and two model urban Mexican diets. Am J Clin Nutr 1996;63:335–341.
Wurtman J, Fernstrom JD. Free amino acid, protein, and fat contents of breast milk from Guatemalan mothers consuming a corn-based diet. Early Hum Dev 1979;3:67–77.
Yoshida A, Leung P, RogersQRHarper AE. Effect of amino acid imbalance on the fate of the limiting amino acid. J Nutr 1966;89:80–90.
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Ramírez, I., DeSantiago, S., Tovar, A.R., Torres, N. (2001). Amino Acid Intake During Lactation and Amino Acids of Plasma and Human Milk. In: Newburg, D.S. (eds) Bioactive Components of Human Milk. Advances in Experimental Medicine and Biology, vol 501. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-1371-1_52
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DOI: https://doi.org/10.1007/978-1-4615-1371-1_52
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