mRNAs in skin surface lipids unveiled atopic dermatitis at 1 month.

BACKGROUND: The molecular pathogenesis of atopic dermatitis (AD), presenting skin barrier dysfunction and abnormal inflammations around 1-2 months, is unreported. OBJECTIVE: We aimed to examine the molecular pathogenesis of very early-onset AD by skin surface lipid-RNA (SSL-RNA) using a non-invasive technology in infants aged 1 and 2 months from a prospective cohort. METHODS: We collected sebum by oil-blotting film of infants aged 1 and 2 months and analysed RNAs in their sebum. We diagnosed AD according to the United Kingdom Working Party's criteria. RESULTS: Infants with AD aged 1 month showed lower expression of genes related to various lipid metabolism and synthesis, antimicrobial peptides, tight junctions, desmosomes and keratinization. They also had higher expression of several genes involved in Th2-, Th17- and Th22-type immune responses and lower expression of negative regulators of inflammation. In addition, gene expressions related to innate immunity were higher in AD infants. Infants aged 1 month with neonatal acne and diagnosed with AD aged 2 months already had gene expression patterns similar to AD aged 1 month in terms of redox, lipid synthesis, metabolism and barrier-related gene expression. CONCLUSION: We identified molecular changes in barrier function and inflammatory markers that characterize the pathophysiology of AD in infants aged 1 month. We also revealed that neonatal acne at 1 month could predict the subsequent development of AD by sebum transcriptome data.

Establishment of mouse Mac-2 binding protein enzyme-linked immunosorbent assay and its application for mouse chronic liver disease models.

AIM: We identified Mac-2 (galectin-3) binding protein (Mac-2bp) as a novel diagnostic and liver fibrosis predicting biomarker for nonalcoholic steatohepatitis in humans. In mouse models, there are no serum biomarkers predicting liver disease severity. In this study, we developed a mouse Mac-2bp enzyme-linked immunosorbent assay (ELISA) system and determined its efficacy for predicting the severity of liver disease in mouse models, especially in non-alcoholic fatty liver disease (NAFLD) models. METHODS: We established several rat monoclonal antibodies against mouse Mac-2bp, selected two clones for the ELISA, and checked the accuracy and reproducibility of the ELISA, especially for NAFLD models and liver fibrosis models. We also investigated the relationships between serum levels and hepatic gene expression of Mac-2bp in mouse models. RESULTS: Our ELISA system had high accuracy and reproducibility (R2 = 0.999). The intra-assay and inter-assay results for the coefficient of variation were 2.0-3.7% and 1.7-6.9%, respectively. The levels of bilirubin, hemoglobin, and chyle did not affect the Mac-2bp serum levels detected by our ELISA kit. In the mouse models, serum Mac-2bp levels increased with liver disease progression (F0/F1/F2/F3, 239.1 ± 36.7 / 259.1 ± 43.0 / 457.5 ± 162.0 / 643.7 ± 116.0 ng/mL; P < 0.0001), and were significantly correlated with hepatic gene expression of Mac-2bp (R = 0.42, P < 0.0001). CONCLUSION: Our mouse Mac-2bp ELISA system effectively predicts severity of NAFLD and liver fibrosis in mouse models.

Non-invasive human skin transcriptome analysis using mRNA in skin surface lipids.

Non-invasive acquisition of mRNA data from the skin can be extremely useful for understanding skin physiology and diseases. Inspired by the holocrine process, in which the sebaceous glands secrete cell contents into the sebum, we focused on the possible presence of mRNAs in skin surface lipids (SSLs). We found that measurable levels of human mRNAs exist in SSLs, where the sebum protects them from degradation by RNases. The AmpliSeq transcriptome analysis was modified to measure SSL-RNA levels, and our results revealed that the SSL-RNAs predominantly comprised mRNAs derived from sebaceous glands, the epidermis, and hair follicles. Analysis of SSL-RNAs non-invasively collected from patients with atopic dermatitis revealed increased expression of inflammation-related genes and decreased expression of terminal differentiation-related genes, consistent with the results of previous reports. Further, we found that lipid synthesis-related genes were downregulated in the sebaceous glands of patients with atopic dermatitis. These results indicate that the analysis of SSL-RNAs is a promising strategy to understand the pathophysiology of skin diseases.

Intestinal Rotation and Physiological Umbilical Herniation During the Embryonic Period.

Drastic changes occur during the formation of the intestinal loop (IL), including elongation, physiological umbilical herniation (PUH), and midgut rotation. Fifty-four sets of magnetic resonance images of embryos between Carnegie stage (CS) 14 and CS 23 were used to reconstruct embryonic digestive tract in three dimensions in the Amira program. Elongation, PUH, and rotation were quantified in relation to the proximal part of the superior mesenteric artery (SMA), designated as the origin. Up to CS 16, IL rotation was initially observed as a slight deviation of the duodenum and colorectum from the median plane. The PUH was noticeable after CS 17. At CS 18, the IL showed a hairpin-like structure, with the SMA running parallel to the straight part and the cecum located to the left. After CS 19, the IL began to form a complex structure as a result of the rapid growth of the small intestinal portion. By CS 20, the IL starting point had moved from the right cranial region to an area caudal to the origin, though elongation of the duodenum was not conspicuous-this was a change of almost 180° in position. The end of the IL remained in roughly the same place, to the left of and caudal to the origin. Notably, the IL rotated around the origin only during earlier stages and gradually moved away, running transversely after CS 19. The movements of the IL may be explained as the result of differential growth, suggesting that IL rotation is passive.