Lactoferrin impedes epithelial cell adhesion in vitro

In the process of host defence against microbial challenge, neutrophils release granule contents with the potential side effect of damaging structural tissues. In the junctional epithelium such damage may contribute to the degeneration and renewal of the epithelial cells attached directly to the tooth (DAT cells), and subsequently to periodontal pocket formation. This study reports on lactoferrin, one of the substances released by neutrophils, and its effects on epithelial cell adhesion, growth, DNA synthesis and spreading of cell colonies at concentrations recorded in the crevicular fluid. We show that, in opposition to what has been reported on bacterial cells, lactoferrin has no effect on the DNA synthesis of attached epithelial cells in model systems attempting to simulate the DAT cells in vivo. However, both iron-saturated and unsaturated lactoferrin hampered cell adhesion, growth and spreading of cell colonies in a dose-dependent manner. These findings suggest that lactoferrin does not affect epithelial cell proliferation but it may have a role in delaying the repair of the DAT cell population during inflammation by interfering with cell adhesion.     

Lactoferrin, myeloperoxidase, lysozyme and eosinophil cationic protein in exudate in delayed type hypersensitivity

A skin window technique was used to study the morphology of leucocytes in upper dermis and exudate during nickel challenge in patients with contact allergy to nickel. Contact allergic patients and healthy volunteers tested with a skin widow without addition of nickel to the chamber medium served as controls. The morphology of the leucocytes in dermis was studied in biopsies taken 8, 24, or 48 h after skin window application, and in a parallel test the morphology of the exudate was examined by sequential collection of the chamber medium during a 48 h period. The infiltrate in dermis of contact allergic patients with nickel challenge in the chamber medium showed a time-dependent increase of mononuclear cells, eosinophils and basophils and a concomitant decrease of polymorphonuclear granulocytes, characteristic of a combined specific and unspecific inflammation. The morphology of the exudate in contact allergic patients exposed to nickel showed a dominance of polymorphonuclear granulocytes throughout the study period, while mononuclear cells, eosinophils and basophils were detected at a much lower quantity and with a considerable delay. Further, we studied the kinetics of the leucocyte granule proteins: lactoferrin, myeloperoxidase, lysozyme and eosinophil cationic protein in exudate fluid in a parallel test. A significant higher flux was found for all during the second day of allergen exposure compared to contact allergic patients without allergen challenge as well as normal volunteers. The increased protein fluxes were not accompanied by an increased flux of polymorphonuclear granulocytes in the exudate.(ABSTRACT TRUNCATED AT 250 WORDS)     

Increase in lactoferrin and elastase α-1-proteinase inhibitor complexes but lack of complement activation and IL-6 response following thoracic surgery

Polymorphonuclear neutrophil (PMN) stimulation and degranulation can be mediated by the cytokines and by complement activation. The aim of the present study was to measure TNFa, IL-lα, IL-6 and C3d in relation to postoperative increase in lactoferrin and elastase α-1-proteinase inhibitor (E α-l-PI) levels. Eleven patients undergoing thoracic surgery took part in the study. Blood leucocytes, E α-l-PI, lactoferrin and C3d were measured preoperatively, at the end of surgery and postoperatively, at 4 h and on day 1, 2, 3 and 5. TNFa, IL-lα and IL-6 were measured preoperatively, at the end of surgery and postoperatively, at 4 h, and on days 1 and 5. The leucocyte count, lactoferrin and E α-l-PI levels increased significantly postoperatively (P < 0.01). There was no significant change in C3d values. Plasma IL-6 levels were unchanged in the postoperative period. Plasma TNFa and IL-lα were detectable at low levels in only two and four patients, respectively. Conclusion: The postoperative increase in blood levels of PMN lactoferrin and E α-l-PI complexes observed in the present study was not accompanied by complement activation, or increased blood levels of IL-6.     

Supplementation of an adapted formula with bovine lactoferrin: 1. Effect on the infant faecal flora

The development of the infant faecal flora was studied over the first three months of life in infants receiving breast milk, a modern adapted formula and adaptations of this formula. Breast-fed infants developed a flora rich in Bifidobacterium sp. Facultative anaerobes were ubiquitous, but in relatively small numbers within the diet group. Other obligate anaerobes, such as Clostridium sp. and Bacteriodes sp. were rarely isolated. Standard formula produced a flora rich in bifidobacteria, but the growth of facultative organisms was not suppressed by this diet. Clostridium sp. and Bacteroides sp. were more common in this feeding group. After the addition of lactoferrin at 10 mg/100 ml to the formula diet, a flora similar to that of the standard formula-fed babies was achieved. Lactoferrin at 100 mg/100 ml was able to establish a "bifidus flora" in half of the babies given this formula, but only at age three months. Clostridium sp. and Bacteroides sp. were common faecal isolates from babies receiving both the lactoferrin diets.     

In the Age of Viral Pandemic,Can Ingredients Inspired by Human Milk and Infant Nutrition Be Repurposed to Support the Immune System?

In 2020, with the advent of a pandemic touching all aspects of global life, there is a renewed interest in nutrition solutions to support the immune system. Infants are vulnerable to infection and breastfeeding has been demonstrated to provide protection. As such, human milk is a great model for sources of functional nutrition ingredients, which may play direct roles in protection against viral diseases. This review aims to summarize the literature around human milk (lactoferrin, milk fat globule membrane, osteopontin, glycerol monolaurate and human milk oligosaccharides) and infant nutrition (polyunsaturated fatty acids, probiotics and postbiotics) inspired ingredients for support against viral infections and the immune system more broadly. We believe that the application of these ingredients can span across all life stages and thus apply to both pediatric and adult nutrition. We highlight the opportunities for further research in this field to help provide tangible nutrition solutions to support one’s immune system and fight against infections.     

Supplementation of an adapted formula with bovine lactoferrin. 2. Effects on serum iron, ferritin and zinc levels

Breast milk provides an excellent supply of most nutrients for newborn infants. Infant formulae should be nutritionally comparable to breast milk especially with regard to critical nutrients like iron and other trace elements. Infant formulae supplemented with various amounts of bovine lactoferrin were given to two groups of infants. These infants were compared with infants receiving unsupplemented formula and breast-fed infants. The effects of these diets on levels of haemoglobin, haematocrit, serum iron, ferritin and zinc were examined for a study period of 150 days. At birth, concentrations of iron, haemoglobin, haematocrit and zinc were comparable in all four feeding groups. The fact that the serum zinc level was not altered by lactoferrin supplementation appears to rule out an in-vivo effect of lactoferrin on zinc nutrition of infants. Ferritin levels of breast-fed infants were significantly higher than in non-supplemented formula-fed infants at day 30 and day 90. This difference was seen only at day 30, when comparing breast-fed infants to lactoferrin-supplemented formula-fed infants. Comparing the infants receiving formulae, the formula supplemented with the higher amount of bovine lactoferrin induced significantly higher serum ferritin levels compared to the unsupplemented formula at day 90 and day 150. These observations favour the idea that lactoferrin may be involved in iron absorption. Since this effect was pronounced only after 90 days, it has to be discussed as to whether this effect is a convincing argument for supplementing infant formulae with bovine lactoferrin.     

乳铁蛋白对MPP+诱导的帕金森病细胞模型炎症损伤的保护作用及机制研究

目的 探讨外源性乳铁蛋白对1-甲基-4-苯基吡啶(MPP⁺)诱导的小鼠神经母细胞瘤N2a细胞帕金森病(PD)模型炎症损伤的保护作用及其机制。方法 以250μmol/L的MPP⁺诱导N2a细胞损伤构建PD细胞模型,将模型随机分为对照组、乳铁蛋白组、MPP⁺组和乳铁蛋白+MPP⁺组。采用CCK-8法检测细胞存活率;Annexin FITC/PI双染法检测细胞凋亡率;Hoechst33342染色检测细胞早期凋亡情况;检测各组的谷胱甘肽过氧化物酶(GSH-Px)活性和丙二醛(MDA)水平;采用实时荧光定量聚合酶链反应(qRT-PCR)检测细胞IL-4、IL-6、IL-13、IL-1β、TNF-α mRNA的表达;Western blotting检测不同浓度MPP⁺(0、100、250、500、1 000μmol/L)N2a细胞的酪氨酸羟化酶(TH)和多巴胺转运体(DAT)蛋白的表达,检测各组的Bcl-2、Bax、Caspase-3、Cleaved Caspase-3、p38、p-p...     

补充乳铁蛋白对新生儿和婴幼儿影响的研究进展

随着经济社会的发展,近几年来人们越来越重视免疫营养素,如各种维生素、益生菌、多不饱和脂肪酸、核苷酸、乳铁蛋白等,这些营养素既可促进生长,保持代谢平衡,又可调节机体免疫力,维持人体内环境稳态。乳铁蛋白(LF)是一种多功能蛋白质,是哺乳动物非特异性免疫系统的第一道防线,乳铁蛋白具有抗微生物、调节免疫、调节肠道菌群及促进肠道细胞增殖及分化等特点。本文就补充乳铁蛋白对新生儿和婴幼儿影响的相关研究进行综述。