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Conifer and broadleaf trees emit volatile organic compounds in the summer. e major components of these emissions are volatile monoterpenes. Using solid phase microextraction ber as the adsorbant, monoterpenes were successfully detected and identi ed in forest air samples. Gas chromatography/mass chromatogram of monoterpenes in the atmosphere of a conifer forest and that of serum from subjects who were walking in a forest were found to be similar each other. e amounts of α-pinene in the subjects became several folds higher a er forest walking. e results indicate that monoterpenes in the atmosphere of conifer forests are transferred to and accumulate in subjects by inhalation while they are exposed to this type of environment.Please cite this article as: Mass Spectrom (Tokyo) 2015; 4(1): A0042

Background: Capillary pericytes (cPCs), the mural cells of microvessels, play an important role in the formation and maintenance of microvessels; however, little is known about the mechanisms of how cPCs regulate angiogenesis. To identify factors that modulate cPC function, genes whose levels were altered in cPCs during neovessel formation were identified through a microarray screen. Methods and Results:Ninjurin1 (nerve injury-induced protein, Ninj1) was selected as a candidate factor for angiogenesis regulation. Ninj1 was expressed in capillary cells including endothelial cells (cECs) and was expressed at a higher level in cPCs. Hypoxia induced the gene expression of Ninj1 in addition of vascular endothelial growth factor (VEGF) in cPCs. When cPCs were co-incubated with a thoracic aorta in a three-dimensional Matrigel system, the length of the EC-tubes sprouting from the aorta was increased. Small interfering RNA-mediated downregulation of Ninj1 in cPCs enhanced these cPCs-mediated angiogenic effects, whereas overexpression of Ninj1 attenuated their effects. The production of angiogenic growth factors, such as VEGF and angiopoietin 1, by cPCs was enhanced by the downregulation of Ninj1, and reduced by the overexpression of Ninj1. also determined. EC Tube Formation Angiogenesis AssayThe EC tube formation assay was performed as previously described. 14 A 40-μl volume of growth factor-reduced Matirgel was added to each well of a 96-well plate at room temperature. The gel was solidified at 37°C for at least 30 min and then seeded with 1×10 4 cells/well in 100 μl medium (EBM2 with 2% FBS and 10 ng/ml VEGF). The assay was performed in a CO2 incubator, with plates incubated at 37°C for 24 h. Images were obtained by phase contrast microscopy and the length of the tube-like structure in each well was measured at 40× magnification. Hind Limb Ischmia Surgery and ImmunocytochemistryMale C57BL/6 mice 12 weeks of age were used for experiments. All animal protocols were approved by the Animal Care and Use Committee of Asahikawa Medical University. Unilateral hindlimb ischemia (HLI) models were established by ligation and excision of the femoral artery/vein as previously described. 16 At predetermined time points, mice were sacrificed by overdose with a pentobarbital-based euthanasia solution (200 mg/kg by intraperitoneal injection). Gastrocnemius muscle samples were collected and stored at −80°C for quantitative polymerase chain reaction (qPCR) analysis. The histological assessment of ischemic limb tissue was performed 14 days after hindlimb surgery. Functional vessels were stained by injecting 300 μl phosphate-buffered saline (PBS) containing rhodamine-labeled G. simplicifolia lectin I (100 μg/ml, Vector Laboratories) via the tail vein. After 5 min, mice were sacrificed and perfused through the heart with PBS followed by 4% paraformaldehyde in PBS, and the gastrocnemius muscle was dissected and embedded in Tissue-Tek OCT medium. Ninj1 expression in 10-μm cross-sections was detected by immunocytochemistry using an anti-Ninj1 ...

Adventitial microvessels, vasa vasorum in the vessel walls, have an active role in the vascular remodeling, although its mechanisms are still unclear. It has been reported that microvascular pericytes (PCs) possess mesenchymal plasticity. Therefore, microvessels would serve as a systemic reservoir of stem cells and contribute to the tissues remodeling. However, most aspects of the biology of multipotent PCs (mPCs), in particular of pathological microvessels are still obscure because of the lack of appropriate methods to detect and isolate these cells. In order to examine the characteristics of mPCs, we established immortalized cells residing in adventitial capillary growing at the injured vascular walls. We recently developed in vivo angiogenesis to observe adventitial microvessels using collagen-coated tube (CCT), which also can be used as an adventitial microvessel-rich tissue. By using the CCT, CD146-or NG2-positive cells were isolated from the adventitial microvessels in the injured arteries of mice harboring a temperature-sensitive SV40 T-antigen gene. Several capillary-derived endothelial cells (cECs) and PCs (cPCs) cell lines were established. cECs and cPCs maintain a number of key endothelial and PC features. Co-incubation of cPCs with cECs formed capillary-like structure in Matrigel. Three out of six cPC lines, termed capillary mPCs demonstrated both mesenchymal stem cell-and neuronal stem cell-like phenotypes, differentiating effectively into adipocytes, osteoblasts, as well as schwann cells. mPCs differentiated to ECs and PCs, and formed capillary-like structure on their own. Transplanted DsRed-expressing mPCs were resident in the capillary and muscle fibers and promoted angiogenesis and myogenesis in damaged skeletal muscle. Adventitial mPCs possess transdifferentiation potential with unique phenotypes, including the reconstitution of capillary-like structures. Their phenotype would contribute to the pathological angiogenesis associated with vascular remodeling. These cell lines also provide a reproducible cellular tool for high-throughput studies on angiogenesis, vascular remodeling, and regeneration as well.

Adventitial abnormalities including enhanced vasa vasorum malformation are associated with development and vulnerability of atherosclerotic plaque. However, the mechanisms of vasa vasorum malformation and its role in vascular remodeling have not been fully clarified. We recently reported that Ninjurin-1 (Ninj1) is a crucial adhesion molecule for pericytes to form matured neovessels. The purpose is to examine if Ninj1 regulate adventitial angiogenesis and affects the vascular remodeling of injured vessels using pericyte-specific Ninj1 deletion mouse model. Mouse femoral arteries were injured by insertion of coiled wire. Four weeks after vascular injury, fixed arteries were decolorized. Vascular remodeling, including intimal hyperplasia and adventitial microvessel formation were estimated in three-dimensional view. Vascular fragility, including blood leakiness was estimated by extravasation of FITC-lectin or -dextran from microvessels. Ninj1 expression was increased in pericytes in response to vascular injury. NG2-CreER/Ninj1loxp mice were treated with tamoxifen (Tam) to induce deletion of Ninj1 in pericyte (Ninj1KO). Tam-treated-NG2-CreER or Tam-nontreated NG2-CreER/Ninj1loxp mice were used as controls. Intimal hyperplasia was significantly enhanced in Ninj1KO compared with controls. Vascular leakiness was significantly enhanced in Ninj1KO. In Ninj1KO, the number of infiltrated macrophages in adventitia was increased, along with the expression of inflammatory cytokines. In conclusion, deletion of Ninj1 in pericytes induces the immature vasa vasorum formation of injured vasculature and exacerbates adventitial inflammation and intimal hyperplasia. Thus, Ninj1 contributes to the vasa vasorum maturation in response to vascular injury, and to reduction of vascular remodeling.