Breast Milk-Derived Limosilactobacillus reuteri Prevents Atopic Dermatitis in Mice via Activating Retinol Absorption and Metabolism in Peyer's Patches.

SCOPE: Supplementing Limosilactobacillus reuteri Fn041, a breast milk-derived probiotic from agricultural and pastoral areas, to maternal mice during late pregnancy and lactation prevents atopic dermatitis (AD) in offspring. This study aims to elucidate the molecular mechanism of Fn041-mediated immune regulation. METHODS AND RESULTS: Fn041 is administered prenatal and postnatal to maternal mice, and to offspring after weaning. The ears are administered with calcipotriol to induce AD. Fn041 treatment significantly alleviates ear inflammation, and reduces mast cell infiltration. Fn041 treatment upregulates and downregulates intestinal ZO-1 and Claudin-2 mRNA expression, respectively. Transcriptome analysis of Peyer's patches reveals that pathways related to DNA damage repair are activated in AD mice, which is inhibited by Fn041 treatment. Fn041 activates pathways related to retinol absorption and metabolism. Untargeted metabolomic analysis reveals that Fn041 treatment increases plasma retinol and kynurenine. Fn041 treatment does not significantly alter the overall cecal microbiota profile, only increases the relative abundances of Ligilactobacillus apodemi, Ligilactobacillus murinus, Akkermansia muciniphila, and Bacteroides thetaiotaomicron. CONCLUSIONS: Fn041 induces anti-AD immune responses directly by promoting the absorption and metabolism of retinol in Peyer's patches, and plays an indirect role by strengthening the mucosal barrier and increasing the abundance of specific anti-AD bacteria in the cecum.

Limosilactobacillus reuteri FN041 prevents atopic dermatitis in pup mice by remodeling the ileal microbiota and regulating gene expression in Peyer's patches after vertical transmission.

Objectives: Limosilactobacillus reuteri FN041 is a potential probiotic bacterium isolated from breast milk in traditional farming and pastoral areas of China. The purpose of this study was to investigate the optimal intervention mode and potential mechanism of FN041 to prevent atopic dermatitis (AD) in mice. Methods: In intervention mode I, FN041 was supplemented to dams during the late trimester and lactation and pups after weaning; in intervention mode II, FN041 was supplemented after pups were weaned. AD was induced in pups with MC903 plus ovalbumin on the ear after weaning. Results: The effect of intervention mode I in preventing AD was significantly better than that of intervention mode II. Compared with the model group, the inflammatory response of the pup's ears, the proportion of spleen regulatory T cells and the plasma IgE were significantly decreased in mice in intervention mode I. Furthermore, the intestinal mucosal barrier was enhanced, and the Shannon index of the ileal microbiota was significantly increased. The microbiota structure deviated from the AD controls and shifted toward the healthy controls according to the PCoA of unweighted UniFrac. The relative abundances of Limosilactobacillus, Faecalibacterium, Bifidobacterium, and Akkermansia in the ileum were significantly increased compared to the AD group. Based on RNA-seq analysis of pups' Peyer's patches (PPs), FN041 inhibits autoimmune pathways such as asthma and systemic lupus erythematosus and activates retinol metabolism and PPAR signaling pathways to reduce inflammatory responses. Intervention mode II also significantly reduced AD severity score, but the reduction was approximately 67% of that of intervention mode I. This may be related to its ineffective remodeling of the ileal microbiota. Conclusion: Prenatal and postnatal administration of FN041 is an effective way to prevent AD in offspring, and its mechanism is related to remodeling of ileal microbiota and PPs immune response.

Triacylglycerol Composition of Breast Milk during Different Lactation Stages.

Triacylglycerol (TAG) composition of breast milk plays an important role in improving digestion, absorption, and metabolism when consumed by infants. This study characterized the TAG profile of human colostrum, transitional, and mature milk samples from 103 women. Significant differences in the TAGs composition of breast milk fat from three lactation stages were observed. The TAGs with high molecular weight and unsaturated fatty acid (such as 1,3-olein-2-palmitin (OPO) and 1(3)-olein-2-palmitin-3(1)-linolein (OPL)) were enriched in colostrum, while the TAGs containing medium-chain fatty acids were more abundant in transitional and mature milk than that in colostrum. Of note, OPL was the most common TAG in breast milk of Chinese women while the most common TAG in breast milk of Western women was OPO. This data will promote the development of infant formulas in terms of the TAG composition more suitable for infants.

Total and sn-2 fatty acid profile of breast milk from women delivering preterm infants under the influence of maternal characteristics.

Data on the total fatty acid (FA) profile and position-specific triacylglycerides (TAGs) in preterm infants' maternal milk are essential for establishing the recommended requirement of FA in preterm infants in China. We aimed to determine the composition and positional distribution of FAs in preterm infants' maternal milk in China and further investigate the effect of maternal background on the FA composition. Breast milk samples (4, 11, 30, 60, and 90 (all ±3) days post-partum) were collected from 59 healthy women delivering preterm infants. The total and sn-2 milk FA composition was determined using gas chromatography. The multivariate statistical analysis showed significant differences in the FA profiles of milk with different lactation times, gestational ages and maternal ages. In particular, the content of linoleic and linolenic acid (ALA) was much higher, whereas the content of docosahexaenoic (DHA) and arachidonic acid were lower in the preterm milk from the Wuxi district than that from America and countries in Europe. The content of sn-2 polyunsaturated FAs (ALA: p = 0.013 and DHA: p = 0.003) were lower in the preterm colostrum from women aged over 30 years. Overall, these results suggest that the European and American standards of preterm formula may not be suitable for Chinese preterm infants, and polyunsaturated FA fortification in the maternal diet or preterm formula is needed for women with advanced age.

Changes in the metabolite profile of breast milk over lactation stages and their relationship with dietary intake in Chinese women: HPLC-QTOFMS based metabolomic analysis.

The aim of the present study was to comprehensively evaluate the changes in the metabolite profile of breast milk over lactation stages and their relationship with dietary intake in Chinese women by HPLC-QTOFMS based metabolomic analysis. The colostrum, transitional milk and mature milk of thirty healthy lactating women were collected for analysis. Eighty-four differential metabolites over lactation stages were identified, including 12 fatty acyls, 15 glycerolipids, 23 glycerophospholipids, 7 sphingolipids, 7 vitamins, 5 nucleotides-related metabolites, 2 amino acids, 1 amino acid derivate, 9 dipeptides, 1 steroid hormone, 1 energy-related metabolite and 1 amine. Partial least-squares regression analysis indicated that the metabolite profiles of the colostrum, transitional milk and mature milk have a strong relationship with dietary intake (R2 values were 0.92, 0.87 and 0.74, respectively). However, among the 84 differential metabolites over lactation stages, only two showed a strong relationship with dietary intake: 1,24,25-(OH)3 vitamin D3 was positively correlated with the dietary intake of meat and eggs, protein and fat; 11ß-hydroxyprogesterone was negatively correlated with the dietary intake of fruit and carbohydrate. After adjusting for dietary intake, the variation trend of all the 84 differential metabolites over lactation stages remained unchanged. In conclusion, 84 differential metabolites in the breast milk of Chinese women over lactation stages were identified, and their variation trend was independent of dietary intake. These metabolites were partially different from those identified in previous metabolomic studies in the Western population. The present study is quite meaningful for understanding the variation of nutritional requirements in Chinese infants at different developmental stages and manufacturing optimal infant formulas for them.

The impact of lactation and gestational age on the composition of branched-chain fatty acids in human breast milk.

Breast milk consumption reduces the incidence of necrotizing enterocolitis (NEC) in preterm infants compared to formula. Branched-chain fatty acids (BCFAs) are present in breast milk but not in most formulas intended for preterm infants. We aimed to determine the composition of BCFAs in the breast milk of mothers with preterm infants, and to understand the impact of gestational age at birth and stage of lactation on BCFA content. The main BCFAs in preterm breast milk were iso-14:0, iso-15:0, anteiso-15:0, iso-16:0, iso-17:0, and anteiso-17:0. Breast milk BCFAs as a percent of total fatty acids (g per 100 g, %) were significantly different across lactation stages, with the highest concentration in colostrum, followed by transitional and mature breast milk (median: 0.41, 0.31, and 0.28%, respectively, p < 0.05). Lower BCFAs in preterm breast milk compared to term breast milk may have been related to maternal intake, or the ability of the mammary gland to extract BCFA from plasma, or differences in mammary gland BCFA synthesis. BCFAs were mainly in the sn-2 position (52-65%), similar to palmitic acid. Overall, preterm and term breast milk BCFAs were similar and showed specific concentration patterns, resembling 16:0 with respect to sn-2 positional distribution. BCFAs were reduced with lactation stage, similar to highly unsaturated fatty acids.

Aqueous extracts from asparagus stems prevent memory impairments in scopolamine-treated mice.

Aqueous extracts from Asparagus officinalis L. stems (AEAS) are rich in polysaccharides, gamma-amino butyric acid (GABA), and steroidal saponin. This study was designed to investigate the effects of AEAS on learning, memory, and acetylcholinesterase-related activity in a scopolamine-induced model of amnesia. Sixty ICR mice were randomly divided into 6 groups (n = 10) including the control group (CT), scopolamine group (SC), donepezil group (DON), low, medium, and high dose groups of AEAS (LS, MS, HS; 1.6 mL kg-1, 8 mL kg-1, 16 mL kg-1). The results showed that 8 mL kg-1 of AEAS used in this study significantly reversed scopolamine-induced cognitive impairments in mice in the novel object recognition test (P < 0.05) and the Y-maze test (P < 0.05), and also improved the latency to escape in the Morris water maze test (P < 0.05). Moreover, it significantly increased acetylcholine and inhibited acetylcholinesterase activity in the hippocampus, which was directly related to the reduction in learning and memory impairments. It also reversed scopolamine-induced reduction in the hippocampal brain-derived neurotrophic factor (BDNF) and the cAMP response element-binding protein (CREB) mRNA expression. AEAS protected against scopolamine-induced memory deficits. In conclusion, AEAS protected learning and memory function in mice by enhancing the activity of the cholinergic nervous system, and increasing BDNF and CREB expression. This suggests that AEAS has the potential to prevent cognitive impairments in age-related diseases, such as Alzheimer's disease.

Preparation and characterization of catalase-loaded solid lipid nanoparticles based on soybean phosphatidylcholine.

BACKGROUND: High-purity soybean phosphatidylcholine (SPC) (94%) were prepared using macroporous resin adsorption chromatography previously. Catalase is a food enzyme for promoting health and protecting against many age-related disease. Solid lipid nanoparticles (SLN) are safe immobilizing systems for efficient protein transportation to biomembranes while avoiding adverse degradation of protein. This study was aimed at developing and characterizing catalase-loaded SLN using SPC as solubilizers and stabilizing agents, to protect catalase from proteolysis. RESULTS: Catalase-loaded SLN were prepared by the double emulsification method and solvent evaporation techniques, using acetone-methylene chloride (1:1, v/v) as an organic solvent, SPC-tripalmitin as oil phase and Poloxamer 188 as a surfactant. The optimized SLN were prepared using an SPC:tripalmitin ratio of 5% (w/w), 20 s plus 30 s sonication, 20 g L⁻¹ Poloxamer 188 and 1:2 (v/v) of oily phase:outer aqueous phase ratio. The mean particle size of SLN was 296.0 ± 7.0 nm, polydispersity index range and zeta potential were 0.322-0.354 and -36.4 ± 0.6, respectively, and encapsulation efficiency reached its maximum of 77.9 ± 1.56%. Catalase, which was found to distribute between the solid lipid and inner aqueous phase, was gradually released from SLN up to 20% within 20 h. Catalase-loaded SLN had stably retained 30% of H2O2-degrading activity for at least 24 h in a proteolytic environment, while free catalase lost its activity within 1 h. CONCLUSION: Catalase can indeed be loaded in tripalmitin-based SLN using SPC as solubilizers and stabilizing agents, which protected it against proteolysis, suggesting the potential application of SPC in delivery and protection of functional food enzyme.