F-36316 A and B, novel vasoactive compounds, isolated from Incrucipulum sp. SANK 10414.

In the course of our screening program for vasoactive compounds using co-culture assay of endothelial cells and fibroblast cells, potent activity was detected in the cultured broth of Incrucipulum sp. SANK 10414. Two active compounds, F-36316 A and B, and a non-active homolog, F-36316 C, were isolated from the broth. The structures of F-36316 A, B and C were elucidated by physicochemical data and spectral analyses, and found to be new 3-acylated tetronic acid homologs. F-36316 A and B induced morphological changes of endothelial cells different from vascular endothelial growth factor (VEGF) or vestaines in the assay with EC50 values of 1.8 and 11.7 µM, respectively. Furthermore, F-36316 A and B suppressed VEGF-induced vascular permeability induction in mice.

Vestaines, novel vasoactive compounds, isolated from Streptomyces sp. SANK 63697.

We conducted a screening program for vasoactive compounds and detected a potent activity in the cultured broth of Streptomyces sp. SANK 63697. From the cultured broth, two active compounds, vestaine A1 and B1, were isolated. The structures of these compounds were elucidated by physicochemical data and spectral analyses, and found to be new compounds.

A Novel Natural Product-Derived Compound, Vestaine A1, Exerts both Pro-Angiogenic and Anti-Permeability Activity via a Different Pathway from VEGF.

BACKGROUND/AIMS: Vascular endothelial growth factor (VEGF) is a key molecule in the regulation of both angiogenesis and vascular permeability. However, it is known that overproduction of VEGF induces abnormal blood vessel formation and these vessels cause several disease pathologies, such as diabetic retinopathy. The purpose of this study was to find novel vasoactive compounds which have different properties from VEGF. METHODS/RESULTS: We screened a natural product library using a co-culture angiogenic assay of endothelial cells and fibroblasts. By focusing on morphological changes of endothelial cells, we isolated the novel compounds vestaine A1 and vestaine B1 from the cultured broth of an actinomycete strain, Streptomyces sp. SANK 63697. Vestaine A1 enhanced tube formation of endothelial cells in Matrigel and suppressed cell death induced by serum deprivation. Vestaine A1 activated both MEK1/2 and PI-3 kinase pathways independently of the VEGF pathway in a dose- and time-dependent fashion. Finally, vestaine A1 potently suppressed VEGF-induced vascular permeability both in vitro and in vivo. CONCLUSION: Vestaine A1 has the potential to exhibit both pro-angiogenic and anti-permeability properties, and would therefore be useful for therapeutic treatment for abnormal vascular permeability-related diseases.

Aromatase controls Sjögren syndrome-like lesions through monocyte chemotactic protein-1 in target organ and adipose tissue-associated macrophages.

Several autoimmune diseases are known to develop in postmenopausal women. However, the mechanism by which estrogen deficiency influences autoimmunity is unknown. Aromatase is an enzyme that converts androgens to estrogens. Herein, we used female aromatase gene knockout (ArKO) mice as a model of estrogen deficiency to investigate the molecular mechanism that underlies the onset and development of autoimmunity. Histological analyses showed that inflammatory lesions in the lacrimal and salivary glands of ArKO mice increased with age. Adoptive transfer of spleen cells or bone marrow cells from ArKO mice into recombination activating gene 2 knockout mice failed to induce the autoimmune lesions. Expression of mRNA encoding proinflammatory cytokines and monocyte chemotactic protein-1 increased in white adipose tissue of ArKO mice and was significantly higher than that in wild-type mice. Moreover, an increased number of inflammatory M1 macrophages was observed in white adipose tissue of ArKO mice. A significantly increased monocyte chemotactic protein-1 mRNA expression of the salivary gland tissue in ArKO was found together with adiposity. Furthermore, the autoimmune lesions in a murine model of Sjögren syndrome were exacerbated by administration of an aromatase inhibitor. These results suggest that aromatase may play a key role in the pathogenesis of Sjögren syndrome-like lesions by controlling the target organ and adipose tissue-associated macrophage.

Localization of TRPV1 and contractile effect of capsaicin in mouse large intestine: high abundance and sensitivity in rectum and distal colon.

We investigated immunohistochemical differences in the distribution of TRPV1 channels and the contractile effects of capsaicin on smooth muscle in the mouse rectum and distal, transverse, and proximal colon. In the immunohistochemical study, TRPV1 immunoreactivity was found in the mucosa, submucosal, and muscle layers and myenteric plexus. Large numbers of TRPV1-immunoreactive axons were observed in the rectum and distal colon. In contrast, TRPV1-positive axons were sparsely distributed in the transverse and proximal colon. The density of TRPV1-immunoreactive axons in the rectum and distal colon was much higher than those in the transverse and proximal colon. Axons double labeled with TRPV1 and protein gene product (PGP) 9.5 were detected in the myenteric plexus, but PGP 9.5-immunoreactive cell bodies did not colocalize with TRPV1. In motor function studies, capsaicin induced a fast transient contraction, followed by a large long-lasting contraction in the rectum and distal colon, whereas in the transverse and proximal colon only the transient contraction was observed. The capsaicin-induced transient contraction from the proximal colon to the rectum was moderately inhibited by an NK1 or NK2 receptor antagonist. The capsaicin-induced long-lasting contraction in the rectum and distal colon was markedly inhibited by an NK2 antagonist, but not by an NK1 antagonist. The present results suggest that TRPV1 channels located on the rectum and distal colon play a major role in the motor function in the large intestine.