Serum levels of bile salt-stimulated lipase and breast feeding

Effects of bile salt-stimulated lipase on blood cells and associations with disease activity in human inflammatory joint disorders

The bile salt-stimulated lipase (BSSL) was originally recognized as a lipolytic enzyme expressed by the exocrine pancreas and in some species, notably humans, the lactating mammary gland, being secreted into the duodenum and with the mother's milk, respectively. However, BSSL is also present in the blood and has been assigned additional functions, even beyond the gastrointestinal tract. Conventional BSSL knockout mice are protected from developing disease in animal models of arthritis, and antibodies directed towards BSSL prevent or mitigate disease in similar models. The aim of this study was to investigate the role of BSSL as a newly discovered player in inflammation and specifically in inflammatory joint disorders. As part of mechanism of action, we here show that BSSL is secreted by neutrophils, interacts with monocytes and stimulates their migration in vitro. An anti-BSSL antibody that blocks the human BSSL-monocyte interaction was shown to simultaneously prevent the signaling pathway by which BSSL induce cell migration. Moreover, in this cohort study we show that BSSL levels are significantly higher in blood samples from patients with rheumatoid arthritis and psoriatic arthritis compared to healthy controls. The BSSL levels in patients' blood also correlated with disease activity scores and established inflammatory markers. Hence, although the mode of action is not yet fully clarified, we conclude that BSSL could be considered a proinflammatory component in the innate immune system and thus a possible novel target for treatment of chronic inflammation.

Human milk cholesterol is associated with lactation stage and maternal plasma cholesterol in Chinese populations

BACKGROUND

Milk cholesterol concentrations throughout lactation were analyzed, and the relationship between maternal plasma cholesterol and milk cholesterol in various Chinese populations was examined.

METHODS

A sub-sample of 1138 lactating women was randomly selected from a large cross-sectional study in China (n = 6481). Milk cholesterol concentrations were determined by HPLC, and concentrations of maternal plasma lipids were determined by an automated biochemical analyzer.

RESULTS

The mean cholesterol concentrations were 200, 171, and 126 mg/L for colostrum, transitional milk, and mature milk, respectively. Cholesterol concentrations differed significantly between stages of lactation (colostrum vs. transitional milk, colostrum vs. mature milk, transitional milk vs. mature milk, all p < 0.001). Concentrations of maternal plasma total cholesterol (TC) (p = 0.02) and low-density lipoprotein cholesterol (LDL-C) (p = 0.03) were significantly associated with milk cholesterol. Milk cholesterol concentrations varied among different ethnicities (Tibetan vs. Hui: 164 vs. 131 mg/L, p = 0.027) but not among different geographic regions.

CONCLUSIONS

The concentration of cholesterol in human milk changes dynamically throughout lactation. Milk cholesterol concentrations are significantly associated with maternal plasma concentrations of TC and LDL-C, and milk cholesterol concentrations vary across ethnicities in China.

IMPACT

Concentrations of milk cholesterol were measured in various Chinese populations. Cholesterol concentrations differ significantly between stages of lactation. Maternal plasma total cholesterol and low-density lipoprotein cholesterol are associated with milk cholesterol. Milk cholesterol concentrations vary across ethnicities in China.

Whole Goat Milk as a Source of Fat and Milk Fat Globule Membrane in Infant Formula

Cow milk is the most common dairy milk and has been extensively researched for its functional, technological and nutritional properties for a wide range of products. One such product category is infant formula, which is the most suitable alternative to feed infants, when breastfeeding is not possible. Most infant formulas are based on cow milk protein ingredients. For several reasons, consumers now seek alternatives such as goat milk, which has increasingly been used to manufacture infant, follow-on and young child formulas over the last 30 years. While similar in many aspects, compositional and functional differences exist between cow and goat milk. This offers the opportunity to explore different formulations or manufacturing options for formulas based on goat milk. The use of whole goat milk as the only source of proteins in formulas allows levels of milk fat, short and medium chain fatty acids, sn-2 palmitic acid, and milk fat globule membrane (MFGM) to be maximised. These features improve the composition and microstructure of whole goat milk-based infant formula, providing similarities to the complex human milk fat globules, and have been shown to benefit digestion, and cognitive and immune development. Recent research indicates a role for milk fat and MFGM on digestive health, the gut–brain axis and the gut–skin axis. This review highlights the lipid composition of whole goat milk-based infant formula and its potential for infant nutrition to support healthy digestion, brain development and immunity. Further work is warranted on the role of these components in allergy development and the advantages of goat milk fat and MFGM for infant nutrition and health.

Cholesterol Content in Human Milk during Lactation: A Comparative Study of Enzymatic and Chromatographic Methods

This study validates a gas chromatography (GC) method for determining the sterol profile of human milk (HM) and compares it with an enzymatic-spectrophotometric (E-S) method. Good linearity ( r > 0.97) and low limits of detection and quantification were obtained with the GC method (<1.8 and <6 μg/100 g of HM, respectively). Suitable intra- and interassay precisions (all <18%) and satisfactory recovery percentages (80-109%) were obtained for both methods. In addition, both methodologies were used to assess cholesterol evolution in HM during lactation, showing a 50% decrease at 6 months versus colostrum. The E-S method overestimated cholesterol content by <20% versus the GC method. The results indicate that both methods may be used by the industry and in research to better understand the differences between the sterol profiles of infant formulas and HM.

Lipid Quality in Infant Nutrition: Current Knowledge and Future Opportunities

Dietary lipids are key for infants to not only meet their high energy needs but also fulfill numerous metabolic and physiological functions critical to their growth, development, and health. The lipid composition of breast milk varies during lactation and according to the mother's diet, whereas the lipid composition of infant formulae varies according to the blend of different fat sources. This report compares the compositions of lipids in breast milk and infant formulae, and highlights the roles of dietary lipids in term and preterm infants and their potential biological and health effects. The major differences between breast milk and formulae lie in a variety of saturated fatty acids (such as palmitic acid, including its structural position) and unsaturated fatty acids (including arachidonic acid and docosahexaenoic acid), cholesterol, and complex lipids. The functional outcomes of these differences during infancy and for later child and adult life are still largely unknown, and some of them are discussed, but there is consensus that opportunities exist for improvements in the qualitative lipid supply to infants through the mother's diet or infant formulae. Furthermore, research is required in several areas, including the needs of term and preterm infants for long-chain polyunsaturated fatty acids, the sites of action and clinical effects of lipid mediators on immunity and inflammation, the role of lipids on metabolic, neurological, and immunological outcomes, and the mechanisms by which lipids act on short- and long-term health.

Bile salt-stimulated lipase plays an unexpected role in arthritis development in rodents

OBJECTIVE

The present study aimed to explore the hypothesis that bile salt-stimulated lipase (BSSL), in addition to being a key enzyme in dietary fat digestion during early infancy, plays an important role in inflammation, notably arthritis.

METHODS

Collagen-induced arthritis (CIA) and pristane-induced arthritis (PIA) in rodents are commonly used experimental models that reproduce many of the pathogenic mechanisms of human rheumatoid arthritis, i.e. increased cellular infiltration, synovial hyperplasia, pannus formation, and erosion of cartilage and bone in the distal joints. We used the CIA model to compare the response in BSSL wild type (BSSL-WT) mice with BSSL-deficient 'knock-out' (BSSL-KO) and BSSL-heterozygous (BSSL-HET) littermates. We also investigated if intraperitoneal injection of BSSL-neutralizing antibodies affected the development or severity of CIA and PIA in mice and rats, respectively.

RESULTS

In two consecutive studies, we found that BSSL-KO male mice, in contrast to BSSL-WT littermates, were significantly protected from developing arthritis. We also found that BSSL-HET mice were less prone to develop disease compared to BSSL-WT mice, but not as resistant as BSSL-KO mice, suggesting a gene-dose effect. Moreover, we found that BSSL-neutralizing antibody injection reduced both the incidence and severity of CIA and PIA in rodents.

CONCLUSION

Our data strongly support BSSL as a key player in the inflammatory process, at least in rodents. It also suggests the possibility that BSSL-neutralizing agents could serve as a therapeutic model to reduce the inflammatory response in humans.

Physiological aspects of human milk lipids and implications for infant feeding: a workshop report

The biology of human milk and lactation helps understand the physiology of breastfed infants. The compositional and biological effects of human milk lipids have received considerable interest regarding their modulating effects on growth, metabolism and functions of the cardiovascular, immune and nervous system.

CONCLUSION

This paper describes key aspects of a scientific workshop focused on current knowledge, unresolved questions and future research needs in the area of human milk lipids and their physiological effects in infants.