Metabolic changes induced by TGF-ß1 via reduced expression of phosphatidylserine decarboxylase during myofibroblast transition.

Metabolic alteration is increasingly recognized as an important pathogenic process that underlies fibrosis across many organ types, and metabolically targeted therapies could become important strategies for reducing fibrosis. In present study, target enzymes that are involved in changes in phospholipid metabolism during fibroblast-to-myofibroblast transition induced by transforming growth factor beta 1 (TGF-ß1) were examined. Different amounts of phospholipids were found in the 2 groups. In response to TGF-ß1 stimulation, 17 lipids decreased and 17 increased. The latter included the phospholipids phosphatidylcholine (PC), phosphatidylserine (PS), and phosphatidylethanolamine (PE). Furthermore, among the rate-limiting enzymes that regulate these phospholipids, phosphatidylserine decarboxylase (PISD), which controls conversion of PS to PE and is localized in mitochondria, decreased in response to TGF-ß1. Knockdown of PISD alone without TGF-ß1 stimulation increased expression of α-smooth muscle actin mRNA and production of total collagen. Taken together, these results indicate that PISD is involved in the mechanism of fibrogenesis by regulating phospholipid metabolism.

Basophil tryptase mMCP-11 plays a crucial role in IgE-mediated, delayed-onset allergic inflammation in mice.

Recent studies have identified nonredundant roles for basophils in immune responses including allergy and protective immunity. It is well known that activated basophils release granule contents such as histamine and proteases as do mast cells. However, the functional significance of basophil-derived proteases remains poorly understood in contrast to those released from mast cells. For this study we generated a line of knockout (KO) mice deficient for mouse mast cell protease-11 (mMCP-11) that is preferentially expressed by basophils rather than mast cells. In spite of normal development of basophils, the mMCP-11-deficient mice showed amelioration of immunoglobulin E-mediated chronic allergic inflammation (IgE-CAI), with reduction of cutaneous swelling, microvascular permeability, and leukocyte infiltration in the skin lesion, when KO mice were compared with wild-type mice. Repeated administration of recombinant mMCP-11 in the skin induced infiltration of leukocytes, including basophils, in a tryptase activity-dependent manner. The transwell migration assay in vitro suggested that mMCP-11-mediated proteolytic products of serum protein promoted migration of basophils, eosinophils, and macrophages via 1 or more G protein-coupled receptors. Thus, basophil tryptase mMCP-11 is a crucial effector molecule for the induction of IgE-CAI. This is the first demonstration that the basophil-derived protease plays a significant role in vivo.

Matrix-assisted laser desorption/ionization imaging mass spectrometry reveals changes of phospholipid distribution in induced pluripotent stem cell colony differentiation.

Induced pluripotent stem cells (iPSCs) are opening up new possibilities for medicine. Understanding the regulation of iPSC biology is important when attempting to apply these cells to disease models or therapy. Changes of lipid metabolism in iPSCs were investigated by matrix-assisted laser desorption/ionization time-of-flight imaging mass spectrometry (MALDI-TOF-IMS). Analysis revealed changes of the intensity and distribution of peaks at m/z 782.5 and 798.5 in iPSC colonies during spontaneous differentiation. Two phosphatidylcholines (PCs) were identified: C44H81NO8P, PC(36:4)[M+H]+ at m/z 782.5 and C42H82NO8P, PC(34:1)[M+K]+ at m/z 798.5. The intensity of PC(36:4) showed an inverse relation between undifferentiated and differentiated iPSC colonies. PC(34:1) displayed a diffuse distribution in undifferentiated iPSC colonies, while it showed a concentric distribution in differentiated iPSC colonies, and was localized at the border of the differentiated and undifferentiated areas or the border between undifferentiated iPSC and feeder cells. These findings suggested that the distribution of lipids changes during the growth and differentiation of iPSCs and that MALDI-TOF-IMS was useful for analyzing these changes. PC(36:4) might play a role in maintaining pluripotency, while PC(34:1) might play a role in the differentiation and spread of iPSCs. Graphical Abstract MALDI Imaging for phosphatidylcholine distribution changes during sponteneous differentiaton of induced pluiripotent stem cells colonies.

Influence of an elemental diet on 5-fluorouracil-induced morphological changes in the mouse salivary gland and colon.

PURPOSE: The elemental diet (ED) Elental® reportedly reduces adverse reactions to chemotherapy in digestive system cancer patients; however, the mechanism is unclear. Therefore, we verified the protective effect of ED against gastrointestinal disorders induced by the antineoplastic drug 5-fluorouracil (5-FU). METHODS: After 5 days of tail vein injections of 40 mg/kg/day 5-FU in female BALB/c mice, the mice were given oral ED (ED group) or dextrin with the same number of calories (control group). We measured the weight of salivary glands and the PAS-positive area of colonic mucosa and verified the antitumor effect in tumor-bearing mice given 5-FU and ED. RESULTS: Although body weight decreased after 5-FU treatment, ED group mice weighed more than control group mice. Additionally, although control mice developed diarrhea after 5-FU treatment, the ED group showed only loose stools. The control group saliva volume was approximately one sixth of the vehicle group volume after 5-FU treatment; this was improved to approximately half in the ED group. The area ratio of PAS-positive cells in the colonic mucosa was reduced by 5-FU treatment, with the ratio being higher in the ED group than that in the control group. Similar tumor growth suppression was observed in the 5-FU and ED groups. CONCLUSIONS: ED alleviated adverse reactions to 5-FU without affecting antitumor activity. Protection against 5-FU-induced weight loss was potentially due to both improved nutritional support with combined ingredients and prevention of diarrhea that is associated with reduced colonic goblet cells and decreased saliva production from reduced salivary gland contraction.

Safety and Efficacy of Elobixibat, an Ileal Bile Acid Transporter Inhibitor, in Elderly Patients With Chronic Idiopathic Constipation According to Administration Time: Interim Analysis of Post-marketing Surveillance.

Background/Aims: Elobixibat, an ileal bile acid transporter (apical sodium-dependent bile acid transporter) inhibitor, was recently launched in Japan for the treatment of chronic idiopathic constipation. We conducted an interim analysis of post-marketing surveillance to evaluate the safety and efficacy of elobixibat in elderly patients with chronic constipation and compared the efficacy according to administration time. Methods: Safety and efficacy outcomes were evaluated through patient interviews for 4 weeks. Results: Adverse drug reactions (ADRs) were observed in 5.24% of the 1049 patients analyzed; diarrhea (2.19%) and abdominal pain (1.81%) were the most common. A serious ADR of death was reported in one patient (0.10%). The incidence of ADRs in the ≥ 65-year old or ≥ 75-year-old subpopulation was similar to that in the total patient population. Mean bowel movements per week significantly increased from 2.9 ± 2.5 at baseline to 5.0 ± 3.1 (P < 0.001) at Week 2 and 5.3 ± 2.6 (P < 0.001) at Week 4. The mean Bristol Stool Form Scale score significantly increased from 2.3 ± 1.4 at baseline to 3.8 ± 1.3 (P < 0.001) at Week 2 and 3.9 ± 1.1 at Week 4 (P < 0.001). Bowel movements significantly increased in the elderly population and subpopulations receiving elobixibat before breakfast, lunch, or dinner. The median time to bowel movement was 5 hours. Conclusion: The results suggested that elobixibat was well-tolerated and efficacious in elderly patients with chronic constipation and can be administered before any meals.

Imaging of lysophosphatidylcholine in an induced pluripotent stem cell-derived endothelial cell network.

INTRODUCTION: Vascular endothelial cell disorders are closely related to cardiovascular disease (CVD) and pulmonary diseases. Abnormal lipid metabolism in the endothelium leads to changes in cell signalling, and the expression of genes related to immunity and inflammation. It is therefore important to investigate the pathophysiology of vascular endothelial disorders in terms of lipid metabolism, using a disease model of endothelium. METHODS: Human induced pluripotent stem cell-derived endothelial cells (iECs) were cultured on a matrigel to form an iEC network. Lipids in the iEC network were investigated by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) imaging mass spectrometry (IMS) analysis. Ion fragments obtained by mass spectrometry were analysed using an infusion method, involving precursor ion scanning with fragment ion. RESULTS: The MALDI TOF IMS analysis revealed co-localized intensity of peaks at m/z 592.1 and 593.1 in the iEC network. Tandem mass spectrometry (MS/MS) analysis by MALDI-imaging, in conjunction with precursor ion scanning using an infusion method with lipid extracts, identified that these precursor ions were lysophosphatidylcholine (LPC) (22:5) and its isotype. CONCLUSION: The MALDI-imaging analysis showed that LPC (22:5) was abundant in an iEC network. As an in vitro test model for disease and potential therapy, present analysis methods using MALDI-imaging combined with, for example, mesenchymal stem cells (MSC) to a disease derived iEC network may be useful in revealing the changes in the amount and distribution of lipids under various stimuli.