Human milk. The Gold Standard. Human milk. Human milk. Human milk. Human milk. 3 Types of Human Milk 4/23/2015

Transcription

1 The Gold Standard Defining characteristic of the class Mammalian Ability to produce designed specifically to nourish the young It is a unique complex fluid with a species specific composition It is the most appropriate sole source of nutrition for infants up to 6 months It evolves to meet the changing needs of the infant during growth and development Is a dynamic, complex fluid with a changing nutrient composition that may vary; Through lactation Over the course of a day Within a feeding From woman to woman This variability provides; Nutrients specifically adapted to the changing needs of the infant An array of flavors and tastes that will stimulate sensory integration 3 Types of Human Milk Colostrum Produced in first few days Denser, with yellow color High concentrations of protein and antibodies 1

2 3 Types of Human Milk Transitional Produced from approx. day 3 to day 10, as transitions to mature Contains high levels of fat, lactose and vitamins to help infant regain birth weight 3 Types of Human Milk Mature Last throughout lactation 2 types Fore- water, vitamins, and protein Hind- richer in lipid and CHO Physical properties ph White color due to emulsified lipids and presence of casein Volume At height of lactation, 1.5 liters (50 oz.) can be produced by the human breast per day Nutritional components of human Water Macronutrients Lactose Oligosaccharides Proteins Lipids Water-soluble Vitamins Fat-soluble Vitamins Minerals & Trace Elements Non-nutritional components of human Lysozyme siga Cytokines Free amino acids Bioactive lipids & CHO Cellular elements Nucleotides Hormones & Growth factors Nitrogen provided by: Protein (80%) Declines over 2 to 4 weeks, then remains constant until weaning Nonprotein nitrogen containing compounds (20%) Remains relatively constant until weaning Greater fraction of total nitrogen than in bovine (5%) 2

3 Whey and Casein 70% whey and 30% casein Whey proteins are more soluble and remain in solution after acidification More easily digested Associated with more rapid gastric emptying α-lactalbumin is the major human whey protein Other whey proteins present only in human and involved in host defense Lysozyme secretory immunoglobulin (siga) First line of defense by lining the GI tract Carbohydrates Lactose Disaccharide Increases in content from colostrum to mature then remains relatively constant Oligosaccharides Carbohydrate polymers Comprise approx. 5% to 10% of total carbohydrates More than 100 different oligosaccharides in human Important prebiotic agents Host defense Stimulating good bacterial intestinal colonization Lipids Major energy-yielding fraction of human ~ 50% of the total calories Triglycerides (more than 98% of the fat in human ) essential fatty acids Linoleic acid [C18:2ω6] Linolenic acid [C18:3ω3] Oleic and Palmitic acids is the most abundant fatty acids Phospholipids Cholesterol Lipids Cholesterol Pattern of fatty acids in human is unique in its composition of long-chain polyunsaturated FA s Arachidonic acid [C20:4 ω6], derivative of linoleic acid Docosahexaenoic acid [C22:6 ω3], derivative of linolenic acid These are found only in human, not in bovine Important for energy and growth, but also very important for the function of retinal and neural tissues Arachidonic and docosahexaenic acids are constituents of retinal and brain phospholipid membranes Variability of Fat Content Total fat content is the most variable Increases slightly throughout lactation Changes over the course of one day Increases during a feed As fore progresses to hind Varies from mother to mother Milk from overnight and obese mothers has been found to have higher fat content Too much fore? 3

4 Minerals and Trace Elements Relatively constant through lactation Calcium and phosphorus are significantly lower than in bovine and formula Macrominerals in human are more bioavailable Are bound to digestible proteins Less bound to fatty acids Present in complexed and ionized states Vitamins Affected by maternal vitamin intake and nutritional status Vitamin K Low in human A single IM dose at birth is adequate Vitamin D Low in human Must be supplemented for exclusively breastfed infants Reside in the whey fraction of human An active-phase protein that exhibits antimicrobial activity when not conjugated to iron Binds to excess iron and prevents bacterial iron uptake, fostering nonpathogenic bacterial growth Functions with other proteins to kill bacteria and viruses Has growth-promoting effect on intestinal epithelium Lysozyme Has antibacterial effects by cleaving amino acids in the bacterial cell wall Secretory IgA (siga) Most common immunoglobulin in human Rapidly transfers into in response to specific antigen challenge Acts to neutralize foreign antigens Concentration greatest in colostrum declines in first 4 weeks postpartum Lowest at 6 months, and thereafter increases slightly, remaining constant till 2 years of lactation Cytokines Multifunctional proteins Produced by immune cells Modulate intestinal epithelial barrier function Cytokines Interleukins (IL-6, IL-8) Interferon (IFN) Tumor necrosis factor (TNF) Function Proinflammatory Proinflammatory Stimulates inflammatory immune activation 4

5 Growth factors Epidermal growth factor (EGF) Transforming growth factor (TGF) Gut luminal surveillance, repair of intestine Promotes epithelial cell growth, suppresses lymphocyte function Enzymes Bile salt-stimulating lipase (BSSL) Platelet-activating factoracetylhydrolase Produces free fatty acids, antibacterial activity Blocks action of plateletactivating factor Nerve growth factor Insulin-like growth factor (IGF) Granulocyte colony-stimulation factor (G-CSF) Vascular endothelial growth factor (VEGF) Growth of neuronal, hepatic, and intestinal cells and tissues Promotes angiogenesis and tissue repair Glutathione peroxidase Nucleotides Prevents lipid peroxidation, anti-inflammatory Enhance T cell maturation, antibody responses, bacterial flora Vitamins A, E and C Antioxidants (scavenge oxygen radicals Hormones Leptin Anti-infective properties, immunomodulation Regulation of food intake and energy metabolism Amino acids Glutamine Intestinal cell fuel, immune response Adiponectin Reduction of proinflammatory cytokines, improves insulin sensitivity, increases fatty acid metabolism Taurine Trophic for intestinal growth Erythropoietin (EPO) Stimulates production of red blood cells Maternal Enteromammary and Bronchomammary Immune System Produces siga when exposed to foreign antigens either via her GI or respiratory tracts Plama cells traverse the lymphatic system and are secreted at mucosal surfaces, including the mammary gland Response is rapid, 3 to 4 days Maternal Enteromammary and Bronchomammary Immune System Intimate contact between mother and baby allows for this system to work Kangaroo Mother Care!!! 5

6 References Ballard O, Marrow AL. composition: nutrients and bioactive factors. Pediatr Clin North Am. 2012;60:49-74 Lawrence R. Host resistance factors and immunologic significance of human. In: Lawrence, RL, Lawrence R, eds. Breastfeeding: A Guide for the Medical Profession. 5 th ed. St. Louis, MO: Mosby; 1999: Newburg DS, Woo JG, Marrow AL. Characteristics and potential functions of human adiponectin. J Pediatr. 2012;156:S41-S46 Picciano MF. Representative values for constituents of human. Pediatr Clin North Am. 2001;48: Riskin A, Almog M, Peri R, Halasz K, Srugo I, Kessel A. Changes in immunomodulatory constituents of human in response to active infection in the nursing infant. Pediatr Res. 2012;71: Questions? Thank you! 6