Aims:To identify an antagonistic strain against Streptomyces scabiei and to characterize the antibiotic agent. The efficacy of the isolated strain in controlling common scab disease was also evaluated. Methods and Results: A bacterial strain antagonistic against S. scabiei was isolated from the soil of a potatocultivating area. This bacterium was identified as a Bacillus species by 16S rRNA gene sequence analysis and was designated Bacillus sp. sunhua. Antibiotics produced by this strain were proven to be stable within a broad pH range and at high temperatures. The culture broth was extracted with ethyl acetate, and then the crude extract was applied to HPLC. Two compounds were isolated and identified as iturin A and macrolactin A by 1 H-NMR, 13 C-NMR, HMBC, HMQC and mass spectrometer. The culture broth of Bacillus sp. sunhua had a suppressive effect on common scab disease in a pot assay, decreasing the infection rate from 75 to 35%. This strain also suppressed Fusarium oxysporum, the pathogen of potato dry rot disease. Conclusions: Bacillus sp. sunhua was shown to inhibit S. scabiei effectively. Significance and Impact of the Study: This is the first report demonstrating that macrolactin A and iturin A inhibit S. scabiei. This study demonstrated the possibility of controlling potato scab disease using Bacillus sp. sunhua.

Aldosterone has been shown to stimulate renal TGF-β1 expression. However, the mechanisms for aldosterone-induced TGF-β1 expression have not been clearly determined in mesangial cells. We examined the role of extracellular-signal regulated kinase 1 and 2 (ERK1/2), c-Jun N-terminal kinase (JNK) and activator protein-1 (AP-1) in the aldosterone-induced TGF-β1 expression in rat mesangial cells. TGF-β1 protein in the conditioned medium released from rat mesangial cells was measured by sandwich ELISA, TGF-β1 mRNA expression was analyzed by Northern blotting, AP-1 DNA binding activity was measured by EMSA and the ERK1/2, JNK activity was analyzed by western blotting. Aldosterone significantly stimulated TGF-β1 protein production and TGF-β1 mRNA expression in mesangial cells in a dose-dependent manner. Aldosterone significantly increased AP-1 DNA binding activity in mesangial cells. Pre-treatment of cells with AP-1 inhibitor, curcumin, blocked aldosterone-induced AP-1 DNA binding activity as well as aldosterone-induced TGF-β1 production. Aldosterone increased phosphorylation of ERK1/2 and JNK in mesangial cells. Pre-treatment of cells with ERK1/2 inhibitor, PD98059, or JNK inhibitor, SP600125 significantly inhibited aldosterone-induced ERK1/2 and JNK activity and subsequently TGF-β1 production, respectively. We conclude that aldosterone-induced TGF-β1 expression in mesangial cells is regulated by the ERK1/2, JNK and AP-1 intracellular signaling pathways.

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Exosomes contain proteins, lipids, RNA, and DNA that mediate intercellular signaling. Exosomes can contribute to the pathological processes of various diseases, although their roles in ocular diseases are unclear. We aimed to isolate exosomes from tear fluids (TF) of patients with Thyroid eye disease (TED) and analyze the exosomal proteins. TFs were collected from eight patients with TED and eight control subjects. The number of TF exosomes were measured using nanoparticle-tracking analysis. The expression of specific proteins in the purified exosome pellets were analyzed using a Proteome Profiler Array Kit. Cultured normal orbital fibroblasts were incubated with TF exosomes from patients with TED and control subjects, and changes in inflammatory cytokine levels were compared. TF exosomes from TED patients showed more exosomes than the control subjects. The expression levels of exosomal proteins vitamin D-binding (VDB) protein, C-reactive protein (CRP), chitinase 3-like 1 (CHI3L1), matrix metalloproteinase-9 (MMP-9), and vascular adhesion molecule-1 (VCAM-1) were significantly increased in patients with TED, compared to those of controls. Orbital fibroblasts exposed to TF exosomes from patients with TED showed significantly higher levels of interleukin (IL)-6, IL-8, and monocyte chemoattractant protein-1 (MCP-1) production than those treated with control TF exosomes. Specific proteins showed higher expression in exosomes from TED patients, implying that they may play keys roles in TED pathogenesis.