Showing papers on "Lactation published in 2007"
TL;DR: The results suggest that intestinally derived bacterial components are transported to the lactating breast within mononuclear cells, which programs the neonatal immune system to recognize specific bacterial molecular patterns and to respond appropriately to pathogens and commensal organisms.
Abstract: OBJECTIVE. We examined the presence of a natural bacterial inoculum in breast milk and its intracellular transport from the maternal intestine to the breast through the circulation. METHODS. Breast milk and peripheral blood were collected aseptically from healthy donors at various times after delivery, and the presence of viable bacteria was determined through plating. Temporal temperature gradient gel electrophoresis was used to examine the bacterial ribosomal DNA content in milk cells, maternal peripheral blood mononuclear cells, and feces and in corresponding infant feces. Blood from nongravid nonlactating women served as control samples. Bacterial translocation to extraintestinal tissues was also evaluated in virgin, pregnant, and lactating mice. RESULTS. Breast milk contained a low total concentration of microbes of CONCLUSIONS. Bacterial translocation is a unique physiologic event, which is increased during pregnancy and lactation in rodents. Human breast milk cells contain a limited number of viable bacteria but a range of bacterial DNA signatures, as also found in maternal peripheral blood mononuclear cells. Those peripheral blood mononuclear cells showed greater biodiversity than did peripheral blood mononuclear cells from control women. Taken together, our results suggest that intestinally derived bacterial components are transported to the lactating breast within mononuclear cells. We speculate that this programs the neonatal immune system to recognize specific bacterial molecular patterns and to respond appropriately to pathogens and commensal organisms.
577 citations
TL;DR: 10 week-old rats born to mothers fed the junk food diet during gestation and lactation developed an exacerbated preference for fatty, sugary and salty foods at the expense of protein-rich foods when compared with offspring fed a balanced chow diet prior to weaning or during lactation alone.
Abstract: Obesity is generally associated with high intake of junk foods rich in energy, fat, sugar and salt combined with a dysfunctional control of appetite and lack of exercise. There is some evidence to suggest that appetite and body mass can be influenced by maternal food intake during the fetal and suckling life of an individual. However, the influence of a maternal junk food diet during pregnancy and lactation on the feeding behaviour and weight gain of the offspring remains largely uncharacterised. In this study, six groups of rats were fed either rodent chow alone or with a junk food diet during gestation, lactation and/or post-weaning. The daily food intakes and body mass were measured in forty-two pregnant and lactating mothers as well as in 216 offspring from weaning up to 10 weeks of age. Results showed that 10 week-old rats born to mothers fed the junk food diet during gestation and lactation developed an exacerbated preference for fatty, sugary and salty foods at the expense of protein-rich foods when compared with offspring fed a balanced chow diet prior to weaning or during lactation alone. Male and female offspring exposed to the junk food diet throughout the study also exhibited increased body weight and BMI compared with all other offspring. This study shows that a maternal junk food diet during pregnancy and lactation may be an important contributing factor in the development of obesity.
417 citations
TL;DR: In this article, the sterol regulatory element binding protein (SREBP) family of transcription factors is recognized as regulating fatty acid and cholesterol biosynthesis, in a manner that responds to diet, and the serine/threonine protein kinase Akt influences this process.
Abstract: The transition from pregnancy to lactation is a critical event in the survival of the newborn since all the nutrient requirements of the infant are provided by milk. While milk contains numerous components, including proteins, that aid in maintaining the health of the infant, lactose and milk fat represent the critical energy providing elements of milk. Much of the research to date on mammary epithelial differentiation has focused upon expression of milk protein genes, providing a somewhat distorted view of alveolar differentiation and secretory activation. While expression of milk protein genes increases during pregnancy and at secretory activation, the genes whose expression is more tightly regulated at this transition are those that regulate lipid biosynthesis. The sterol regulatory element binding protein (SREBP) family of transcription factors is recognized as regulating fatty acid and cholesterol biosynthesis. We propose that SREBP1 is a critical regulator of secretory activation with regard to lipid biosynthesis, in a manner that responds to diet, and that the serine/threonine protein kinase Akt influences this process, resulting in a highly efficient lipid synthetic organ that is able to support the nutritional needs of the newborn.
334 citations
01 Jan 2007
TL;DR: It is proposed that SREBP1 is a critical regulator of secretory activation with regard to lipid biosynthesis, in a manner that responds to diet, and that the serine/threonine protein kinase Akt influences this process, resulting in a highly efficient lipid synthetic organ that is able to support the nutritional needs of the newborn.
Abstract: The transition from pregnancy to lactation is a critical event in the survival of the newborn since all the nutrient requirements of the infant are provided by milk. While milk contains numerous components, including proteins, that aid in maintaining the health of the infant, lactose and milk fat represent the critical energy providing elements of milk. Much of the research to date on mammary epithelial differentiation has focused upon expression of milk protein genes, providing a somewhat distorted view of alveolar differentiation and secretory activation. While expression of milk protein genes increases during pregnancy and at secretory activation, the genes whose expression is more tightly regulated at this transition are those that regulate lipid biosynthesis. The sterol regulatory element binding protein (SREBP) family of transcription factors is recognized as regulating fatty acid and cholesterol biosynthesis. We propose that SREBP1 is a critical regulator of secretory activation with regard to lipid biosynthesis, in a manner that responds to diet, and that the serine/threonine protein kinase Akt influences this process, resulting in a highly efficient lipid synthetic organ that is able to support the nutritional needs of the newborn.
319 citations
TL;DR: There are differences in the control of tissue mobilization between PP and MP cows which may promote nutrient partitioning into growth as well as milk during the first lactation.
285 citations
TL;DR: The data show that the highest amount of all oligosaccharides is present at day 4 postpartum and then decreases by about 20% at day 30 of lactation, indicating the protective role played by these substances against different infectious agents in different organs and systems of the breastfed baby.
Abstract: Twenty-one oligosaccharides of human milk were quantified by high-performance anion-exchange chromatography. Milk samples were collected from 18 mothers during the first 3 mo of lactation. The data show that the highest amount of all oligosaccharides is present at day 4 postpartum (20 g l(-1)) and then decreases by about 20% at day 30 of lactation. The protective role played by these substances against different infectious agents, in different organs and systems of the breastfed baby, is emphasized.
281 citations
TL;DR: Investigation of the changes in chemical composition, nitrogen fraction distribution, and AA profile of milk samples obtained during lactation from the Jiangyue breed of donkey in Northwest China demonstrated that donkey milk is rich in beta-lactoglobulin and lysozyme.
244 citations
TL;DR: Results show that substantial regulation of lipid synthesis occurs at the level of mRNA expression and that some of the regulation points differ substantially from the liver, and implicate the transcription factor SREBP-1c in regulation of part of the pathway.
Abstract: The mammary gland of the lactating mouse synthesizes and secretes milk lipid equivalent to its entire body weight in a single 20-day lactation cycle, making it one of the most active lipid syntheti...
241 citations
TL;DR: The works of pioneers that have led to the current understanding of the biochemical and endocrinological processes involved in the initiation of human lactation are described.
Abstract: Theories for the origin of milk have been recorded since the time of Ancient Greeks. In those times it was believed that milk was derived from special vessels that connected the uterus to the breasts. The "chyle theory" on the origin of milk was another prominent theory which persisted well into the nineteenth century before the realisation that milk components were derived from blood and some milk constituents were actually synthesized within the breasts. The demonstration that milk ejection was the expulsion of milk that had already been secreted and that milk secretion was a separate continuous process, set the background for the development for the current understanding of milk synthesis and secretion. Today we know that there are two stages in the initiation of lactation- secretory differentiation and secretory activation. Secretory differentiation represents the stage of pregnancy when the mammary epithelial cells differentiate into lactocytes with the capacity to synthesize unique milk constituents such as lactose. This process requires the presence of a 'lactogenic hormone complex' of the reproductive hormones, estrogen, progesterone, prolactin and some metabolic hormones. Secretory activation on the other hand, is the initiation of copious milk secretion and is associated with major changes in the concentrations of many milk constituents. The withdrawal of progesterone triggers the onset of secretory activation but prolactin, insulin and cortisol must also be present. This review describes the works of pioneers that have led to our current understanding of the biochemical and endocrinological processes involved in the initiation of human lactation.
238 citations
TL;DR: The results demonstrate that the proteome of milk is more complex than has previously been reported and a significant fraction of minor milk proteins are involved in protection against infection.
Abstract: Besides providing nutrition to the newborn, milk also protects the neonate and the mammary gland against infection. As well as the six major proteins, bovine milk contains minor proteins, not all of which have been characterized. In this study, we have subjected bovine skim milk, whey, and milk fat globule membrane (MFGM) fractions to both direct liquid chromatography-tandem mass spectrometry (LC-MS/MS), and two-dimensional electrophoresis (2-DE) followed by matrix assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS) of individual protein spots to better characterize the repertoire of minor milk proteins, particularly those involved with host defense. Milk from peak lactation as well as during the period of colostrum formation and during mastitis were analyzed to gain a more complete sampling of the milk proteome. In total, 2903 peptides were detected by LC-MS and 2770 protein spots by 2-DE. From these, 95 distinct gene products were identified, comprising 53 identified through direct LC-MS/MS and 57 through 2-DE-MS. The latter were derived from a total of 363 spots analyzed with 181 being successfully identified. At least 15 proteins were identified that are involved in host defense. These results demonstrate that the proteome of milk is more complex than has previously been reported and a significant fraction of minor milk proteins are involved in protection against infection.
232 citations
TL;DR: It is demonstrated that BCRP is responsible for pumping riboflavin (vitamin B2) into milk, thus supplying the young with this important nutrient and establishes the principle that an ABC transporter can transport a vitamin into milk and raises the possibility that other vitamins and nutrients are likewise secreted into milk by ABC transporters.
Abstract: The multidrug transporter breast cancer resistance protein (BCRP/ABCG2) is strongly induced in the mammary gland during pregnancy and lactation. We here demonstrate that BCRP is responsible for pumping riboflavin (vitamin B2) into milk, thus supplying the young with this important nutrient. In Bcrp1−/− mice, milk secretion of riboflavin was reduced >60-fold compared to that in wild-type mice. Yet, under laboratory conditions, Bcrp1−/− pups showed no riboflavin deficiency due to concomitant milk secretion of its cofactor flavin adenine dinucleotide, which was not affected. Thus, two independent secretion mechanisms supply vitamin B2 equivalents to milk. BCRP is the first active riboflavin efflux transporter identified in mammals and the first transporter shown to concentrate a vitamin into milk. BCRP activity elsewhere in the body protects against xenotoxins by reducing their absorption and mediating their excretion. Indeed, Bcrp1 activity increased excretion of riboflavin into the intestine and decreased its systemic availability in adult mice. Surprisingly, the paradoxical dual utilization of BCRP as a xenotoxin and a riboflavin pump is evolutionarily conserved among mammals as diverse as mice and humans. This study establishes the principle that an ABC transporter can transport a vitamin into milk and raises the possibility that other vitamins and nutrients are likewise secreted into milk by ABC transporters.
TL;DR: DMI was identified as the principal component of EB influencing subsequent fertility and results indicate that milk protein content and plasma IGF-I concentration in early lactation may be useful indicators of reproductive efficiency.
TL;DR: It is shown for the first time that a prenatally induced nephron deficit can be restored by correcting growth restriction during lactation and the prenatal and postnatal nutritional environments in the programming of adult hypertension, associated with distinct renal changes are identified.
Abstract: Uteroplacental insufficiency in the rat restricts fetal growth, impairs mammary development, compromising postnatal growth; and increases adult BP. The roles of prenatal and postnatal nutritional restraint on later BP and nephron endowment in offspring from mothers that underwent bilateral uterine vessel ligation (restricted) on day 18 of pregnancy were examined. Sham surgery (control) and a group of rats with reduced litter size (reduced; litter size reduced at birth to five, equivalent to restricted group) were used as controls. Offspring (control, reduced, and restricted) were cross-fostered on postnatal day 1 onto a control (normal lactation) or restricted (impaired lactation) mother. BP in male offspring was determined by tail cuff at 8, 12, and 20 wk of age, with glomerular number and volume (Cavalieri/Physical Dissector method) and renal angiotensin II type 1 receptor (AT(1)R) mRNA expression (real-time PCR) determined at 6 mo. Restricted-on-restricted male offspring developed hypertension (+16 mmHg) by 20 wk together with a nephron deficit (-26%) and glomerular hypertrophy (P < 0.05). In contrast, providing a normal lactational environment to restricted offspring improved postnatal growth and prevented the nephron deficit and hypertension. Reduced-on-restricted pups that were born of normal weight but with impaired growth during lactation subsequently grew faster, developed hypertension (+16 mmHg), had increased AT(1A)R and AT(1B)R mRNA expression (P < 0.05), but had no nephron deficit. Our study identifies the prenatal and postnatal nutritional environments in the programming of adult hypertension, associated with distinct renal changes. It is shown for the first time that a prenatally induced nephron deficit can be restored by correcting growth restriction during lactation.
TL;DR: In this article, the breast lesion most commonly found during lactation and manifests as either pseudolipoma, a cystic mass with a fat-fluid level, or pseudohamartoma.
Abstract: During pregnancy and lactation, the breast can be affected by a variety of specific and unique disorders, including benign disorders closely related to physiologic changes, inflammatory and infectious diseases, juvenile papillomatosis, and benign and malignant tumors. Patients with pregnancy-associated breast carcinoma tend to have more advanced neoplasms at diagnosis and a poorer prognosis due to delayed diagnosis and a more aggressive biologic pattern. Pregnancy-related Burkitt lymphoma characteristically manifests with bilateral and diffuse involvement of the breasts. Fibroadenoma may manifest with growth, infarction, large cysts, prominent ducts, and secretory hyperplasia during pregnancy and lactation. Galactocele is the breast lesion most commonly found during lactation and manifests as either pseudolipoma, a cystic mass with a fat-fluid level, or pseudohamartoma. Tumors and diseases affecting the breasts during pregnancy and lactation are basically the same as those observed in nonpregnant women but may have a different appearance. The sensitivity of mammography in pregnant and lactating women is decreased due to increased parenchymal density. Instead, ultrasonography is the most appropriate radiologic method for evaluating breast masses in this setting and is particularly useful in the diagnosis and treatment of abscesses. Knowledge of the unique entities that are specifically related to pregnancy and lactation and of their radiologic-pathologic appearances can help the radiologist make the correct diagnosis.
TL;DR: To study pharmacokinetics of levetiracetam (LEV) during pregnancy, delivery, lactation, and in the neonatal period.
Abstract: Purpose: To study pharmacokinetics of levetiracetam (LEV) during pregnancy, delivery, lactation, and in the neonatal period. Methods: Fourteen women with epilepsy receiving LEV treatment during pregnancy and lactation contributed with 15 pregnancies to this prospective study in which LEV concentrations in plasma and breast milk were determined. Trough maternal plasma samples were collected each trimester, and at baseline after delivery. Blood samples were obtained at delivery from mothers, from the umbilical cord, and from newborns during 2 days after delivery. LEV concentration was also determined in breast milk and in plasma collected from 11 of the mothers and their suckling infants after birth. Results: The umbilical cord/maternal plasma concentration ratios ranged from 0.56-2.0 (mean 1.15, n = 13). LEV plasma concentrations in the neonates declined with an estimated half-life of 18 h (n = 13). The mean milk/maternal plasma concentration ratio was 1.05 (range, 0.78-1.55, n = 11). The infant dose of LEV was estimated to 2.4 mg/kg/day, equivalent to 7.9% of the weight-normalized maternal dose. Plasma concentrations in breastfed were approximately 13% of the mother's plasma levels. Maternal plasma concentrations during third trimester were only 40% of baseline concentrations outside pregnancy (p < 0.001, n = 7) Conclusions: Our observations suggest considerable transplacental transport of LEV and fairly slow elimination in the neonate. Plasma concentrations of LEV in nursed infants are low despite an extensive transfer of LEV into breast milk. Pregnancy appears to enhance the elimination of LEV resulting in marked decline in plasma concentration, which suggests that therapeutic monitoring may be of value. (Less)
TL;DR: The animals that received leptin during lactation become more protected against fat accumulation in adult life and seem to be more sensitive to the short- and long-term regulation of food intake by leptin.
Abstract: The intake of physiological doses of leptin during lactation in rats prevents obesity in later life
TL;DR: It is suggested that in utero and lactational exposure to glyphosate-Roundup® may induce significant adverse effects on the reproductive system of male Wistar rats at puberty and during adulthood.
Abstract: Glyphosate is the active ingredient and polyoxyethyleneamine is the surfactant present in the herbicide Roundup® formulation commercialized in Brazil. The aim of this study was to assess the reproductive effects of glyphosate-Roundup® on male and female offspring of Wistar rats exposed during pregnancy and lactation. Dams were treated orally with water or 50, 150 or 450 mg/kg glyphosate during pregnancy (21–23 days) and lactation (21 days). These doses do not correspond to human exposure levels. The results showed that glyphosate-Roundup® did not induce maternal toxicity but induced adverse reproductive effects on male offspring rats: a decrease in sperm number per epididymis tail and in daily sperm production during adulthood, an increase in the percentage of abnormal sperms and a dose-related decrease in the serum testosterone level at puberty, and signs of individual spermatid degeneration during both periods. There was only a vaginal canal-opening delay in the exposed female offspring. These findings suggest that in utero and lactational exposure to glyphosate-Roundup® may induce significant adverse effects on the reproductive system of male Wistar rats at puberty and during adulthood.
TL;DR: Transport kinetic studies indicate that glucose transport across the plasma membrane of the lactating bovine mammary epithelial cell has a K(m) value of 8.29 mM for 3-O-methyl-D-glucose and can be inhibited by both cytochalasin-B and phloretin, indicating a facilitative transport process.
TL;DR: The effects of live Saccharomyces cerevisiae supplementation to 72 Saanen dairy goats in early lactation were investigated and BCS was not affected by the treatment, but treated animals had greater DMI.
TL;DR: PBDEs have been shown to reduce T4 concentrations in several studies, but this is the first study demonstrating endocrine disruption at low doses and the adipose tissue concentration of PBDE-99 measured in this study was close to those reported in non-occupationally exposed humans.
TL;DR: Research into the physiology of breastfeeding provides a foundation for evidence-based treatment of breastfeeding difficulties and can be used as biochemical markers of the onset of copious milk secretion.
TL;DR: The unique properties of milk as a mediator of biochemical messages will be presented and the clinical significance of breastfeeding in the prevention of neonatal gastrointestinal diseases will be discussed.
Abstract: Not only does breast milk provides an ideal nutrient composition for the newborn, but it also contains a variety of substances that may actively influence growth and development of the infant and stimulate neonatal protection against gastrointestinal diseases. Hormones, growth factors, cytokines and even whole cells are present in breast milk and act to establish biochemical and immunological communication between mother and child. In addition, milk nutrients such as nucleotides, glutamine and lactoferrin have been shown to influence gastrointestinal development and host defense. The unique properties of milk as a mediator of biochemical messages will be presented and the clinical significance of breastfeeding in the prevention of neonatal gastrointestinal diseases will be discussed.
TL;DR: The tendency toward higher milk yield for glycerin-supplemented cows during wk 6 of lactation (52 vs. 46 kg/d) after the supplementation period suggested a potential benefit of dry Glycerin on subsequent milk production, perhaps through changes in metabolism, which requires further investigation.
TL;DR: The results are consistent with the literature and highlight the important role that BCS and BW loss has on milk production, irrespective of the system of farming.
TL;DR: The storage of human milk for use later by the mother's own infant or an unrelated recipient has an impact on its constituents, and glass is the least destructive container.
Abstract: The storage of human milk for use later by the mother's own infant or an unrelated recipient has an impact on its constituents. These effects involve the storage container, heating, cooling and freezing the milk. Overall, glass is the least destructive container. Milk can be safely refrigerated for 72 h with little change. Freezing destroys cellular activity and reduces vitamins B6 and C. Boiling, in addition, destroys lipase and reduces the effect of immunoglobulin A and secretory immunoglobulin A. The nutrient value of human milk is essentially unchanged, but the immunological properties are reduced by various storage techniques.
TL;DR: Exposure to prenatal stress results in long-lasting behavioural and neuroendocrine alterations in the female offspring, which are manifested during the lactation period, and implicates PS as a potential risk factor for the development of postpartum mood disorders.
TL;DR: A number of milk properties including ES, pH, protein content, and Ca2+ concentration could be useful for identifying the point of transition from colostrum to the early lactation period.
TL;DR: When sows kept under commercial conditions were put into crates in the early 1960s, the neuro-endocrine regulation of the maternal behavior in these domestic animals was disputed and today a significant body of knowledge has accumulated to support the hormonal regulation of sow maternal behavior.
TL;DR: Exposure to fish oil in pregnancy was associated with increased n-3 long-chain polyunsaturated fatty acids (LCPUFAs) in breast milk, particularly in early lactation, and this was positively associated with infant DHA status at 1 y.
Abstract: This study evaluated the longitudinal effect of fish oil in pregnancy on breast milk fatty acid composition and infant outcomes. In a randomized, controlled trial, 98 women received 2.2 g docosahexaenoic acid (DHA) and 1.1 g eicosapentaenoic acid (EPA) or olive oil from 20 wk of gestation until delivery. Fatty acid composition in breast milk (at 3 d, 6 wk, and 6 mo) and infant erythrocyte membranes (at 1 y) were determined by gas liquid chromatography. Breast milk fatty acids were examined in relationship to growth and development. Compared with control group, breast milk from women who received fish oil had proportionally higher DHA and EPA levels at 3 d and 6 wk after delivery, but this difference was no longer apparent by 6 mo. Infant DHA status at 1 y of age was directly related to DHA levels at 3 d, 6 wk, and 6 mo postpartum (but not to antenatal supplementation). Both EPA and DHA in breast milk were positively correlated with Griffith's developmental scores including hand and eye coordination. Thus, supplementation in pregnancy was associated with increased n-3 long-chain polyunsaturated fatty acids (LCPUFAs) in breast milk, particularly in early lactation, and this was positively associated with infant DHA status at 1 y.
TL;DR: The results suggest that maternal exposure to FLX during pregnancy and lactation results in enduring behavioral alterations in male and female pups throughout life.
Abstract: Background/Aims: Fluoxetine (FLX) has been widely prescribed for depression during pregnancy and/or lactation. Since serotonin is a neurotrophic factor, the use of FLX by mothers co