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With 5 figures and 2 tables Use of resistance genes would be the most effective way to address Fusarium wilt caused by Fusarium oxysporum f.sp. melonis in melon. In this study, based on the BAC 31O16 sequence which contains the cluster of melon resistance gene homologue, we developed four new DNA markers linked to Fom‐1, a dominant resistance gene against F. oxysporum f.sp. melonis races 0 and 2. Linkage analysis using 125 F2 plants derived from the cross between P11 (fom‐1fom‐1) and MR‐1 (Fom‐1Fom‐1) indicated that Fom‐1 was located between CAPS markers C‐MRGH12 and 62‐CAPS at a distance of 0.4 and 1.2 cM, respectively. Map position of Fom‐1 was confirmed using another mapping population consisting of 104 recombinant inbred lines derived from the cross P11 × MR‐1. The analysis of 43 fixed lines and 27 commercial F1 hybrids showed that the developed DNA markers linked to Fom‐1 correctly predicted the genotype in relation to the variety, suggesting that the region around the Fom‐1 locus is very polymorphic or there is no linkage disequilibrium between the locus and the marker loci. [ABSTRACT FROM AUTHOR]

Effects of the resistant cultivars of melon on the powdery mildew fungus, Sphaerotheca fuliginea, were investigated in a melon-growing area of Japan. Powdery mildew fungi were isolated from four melon cultivars ('HN21', 'Quincy', 'Earl's Knight Natsu 2' and 'Earl's Miyabi Natsu 2') which are resistant to different races of S. fidiginea. 'HN21' is resistant to races 1 and N1, 'Quincy' and 'Earl's Knight Natsu 2' are resistant to races 1 and N2, and 'Earl's Miyabi Natsu 2' is resistant to races 1, N1 and N2. All 155 strains isolated from 'HN21' were identified as race N2. Seventy out of 81 strains isolated from 'Quincy' and 'Earl's Knight Natsu 2' were identified as race N1, while other strains were identified as races 1, 2US, N2 and N3. Nineteen out of 29 strains isolated from 'Earl's Miyabi Natsu 2' were identified as race N3, while other strains were identified as races 1, 2US, N1 and N4. These results suggest that, although the resistant cultivars are extremely effective for protecting the plants from their respective races, a race succession rapidly takes place, even in a small area, and other minor races become predominant. [ABSTRACT FROM AUTHOR]

Background Although apoptosis and cell proliferation have been extensively investigated in atherosclerosis and restenosis postinjury, the communication between these 2 cellular events has not been evaluated. Here, we report an inextricable communicative link between apoptosis and smooth muscle cell proliferation in the promotion of vascular remodeling postinjury. Methods and Results Cathepsin K-mediated caspase-8 maturation is a key initial step for oxidative stress-induced smooth muscle cell apoptosis. Apoptotic cells generate a potential growth-stimulating signal to facilitate cellular mass changes in response to injury. One downstream mediator that cathepsin K regulates is PLF-1 (proliferin-1), which can potently stimulate growth of surviving neighboring smooth muscle cells through activation of PI3K/Akt/p38MAPK (phosphatidylinositol 3-kinase/protein kinase B/p38 mitogen-activated protein kinase)-dependent and -independent mTOR (mammalian target of rapamycin) signaling cascades. We observed that cathepsin K deficiency substantially mitigated neointimal hyperplasia by reduction of Toll-like receptor-2/caspase-8-mediated PLF-1 expression. Interestingly, PLF-1 blocking, with its neutralizing antibody, suppressed neointima formation and remodeling in response to injury in wild-type mice. Contrarily, administration of recombinant mouse PLF-1 accelerated injury-induced vascular actions. Conclusions This is the first study detailing PLF-1 as a communicator between apoptosis and proliferation during injury-related vascular remodeling and neointimal hyperplasia. These data suggested that apoptosis-driven expression of PLF-1 is thus a novel target for treatment of apoptosis-based hyperproliferative disorders.

Background Exposure to chronic psychosocial stress is a risk factor for atherosclerosis-based cardiovascular disease. We previously demonstrated the increased expressions of cathepsin S (CatS) in atherosclerotic lesions. Whether CatS participates directly in stress-related neointimal hyperplasia has been unknown. Methods and Results Male wild-type and CatS-deficient mice that underwent carotid ligation injury were subjected to chronic immobilization stress for morphological and biochemical studies at specific times. On day 14 after stress/surgery, stress enhanced the neointima formation. At the early time points, the stressed mice had increased plaque elastin disruption, cell proliferation, macrophage accumulation, mRNA and/or protein levels of vascular cell adhesion molecule-1, angiotensin II type 1 receptor, monocyte chemoattractant protein-1, gp91 phox , stromal cell-derived factor-1, C-X-C chemokine receptor-4, toll-like receptor-2, toll-like receptor-4, SC 35, galectin-3, and CatS as well as targeted intracellular proliferating-related molecules (mammalian target of rapamycin, phosphorylated protein kinase B, and p-glycogen synthase kinase-3α/β). Stress also increased the plaque matrix metalloproteinase-9 and matrix metalloproteinase-2 mRNA expressions and activities and aorta-derived smooth muscle cell migration and proliferation. The genetic or pharmacological inhibition of CatS by its specific inhibitor (Z- FL -COCHO) ameliorated the stressed arterial targeted molecular and morphological changes and stressed aorta-derived smooth muscle cell migration. Both the genetic and pharmacological interventions had no effect on increased blood pressure in stressed mice. Conclusions These results demonstrate an essential role of CatS in chronic stress-related neointimal hyperplasia in response to injury, possibly via the reduction of toll-like receptor-2/toll-like receptor-4-mediated inflammation, immune action, and smooth muscle cell proliferation, suggesting that CatS will be a novel therapeutic target for stress-related atherosclerosis-based cardiovascular disease.

Background: Exposure to psychosocial stress is a risk factor for cardiovascular disease, including vascular aging and regeneration. Given that dipeptidyl peptidase-4 (DPP4) regulates several intracellular signaling pathways associated with the glucagon-like peptide-1 (GLP-1) metabolism, we investigated the role of DPP4/GLP-1 axis in vascular senescence and ischemia-induced neovascularization in mice under chronic stress, with a special focus on adiponectin -mediated peroxisome proliferator activated receptor-γ/its co-activator 1α (PGC-1α) activation., Methods and Results: Seven-week-old mice subjected to restraint stress for 4 weeks underwent ischemic surgery and were kept under immobilization stress conditions. Mice that underwent ischemic surgery alone served as controls. We demonstrated that stress impaired the recovery of the ischemic/normal blood-flow ratio throughout the follow-up period and capillary formation. On postoperative day 4, stressed mice showed the following: increased levels of plasma and ischemic muscle DPP4 and decreased levels of GLP-1 and adiponectin in plasma and phospho-AMP-activated protein kinase α (p-AMPKα), vascular endothelial growth factor, peroxisome proliferator activated receptor-γ, PGC-1α, and Sirt1 proteins and insulin receptor 1 and glucose transporter 4 genes in the ischemic tissues, vessels, and/or adipose tissues and numbers of circulating endothelial CD31 + /c-Kit + progenitor cells. Chronic stress accelerated aortic senescence and impaired aortic endothelial sprouting. DPP4 inhibition and GLP-1 receptor activation improved these changes; these benefits were abrogated by adiponectin blocking and genetic depletion., Conclusions: These results indicate that the DPP4/GLP-1-adiponectin axis is a novel therapeutic target for the treatment of vascular aging and cardiovascular disease under chronic stress conditions., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Background: DPP4 (Dipeptidyl peptidase-4)-GLP-1 (glucagon-like peptide-1) and its receptor (GLP-1R) axis has been involved in several intracellular signaling pathways. The Adrβ3 (β3-adrenergic receptor)/CXCL12 (C-X-C motif chemokine 12) signal was required for the hematopoiesis. We investigated the novel molecular requirements between DPP4-GLP-1/GLP-1 and Adrβ3/CXCL12 signals in bone marrow (BM) hematopoietic stem cell (HSC) activation in response to chronic stress., Methods and Results: Male 8-week-old mice were subjected to 4-week intermittent restrain stress and orally treated with vehicle or the DPP4 inhibitor anagliptin (30 mg/kg per day). Control mice were left undisturbed. The stress increased the blood and brain DPP4 levels, the plasma epinephrine and norepinephrine levels, and the BM niche cell Adrβ3 expression, and it decreased the plasma GLP-1 levels and the brain GLP-1R and BM CXCL12 expressions. These changes were reversed by DPP4 inhibition. The stress activated BM sca-1 high c-Kit high CD48 low CD150 high HSC proliferation, giving rise to high levels of blood leukocytes and monocytes. The stress-activated HSC proliferation was reversed by DPP4 depletion and by GLP-1R activation. Finally, the selective pharmacological blocking of Adrβ3 mitigated HSC activation, accompanied by an improvement of CXCL12 gene expression in BM niche cells in response to chronic stress., Conclusions: These findings suggest that DPP4 can regulate chronic stress-induced BM HSC activation and inflammatory cell production via an Adrβ3/CXCL12-dependent mechanism that is mediated by the GLP-1/GLP-1R axis, suggesting that the DPP4 inhibition or the GLP-1R stimulation may have applications for treating inflammatory diseases., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Background: The cysteine protease cathepsin K (CatK) has been implicated in the pathogenesis of cardiovascular disease. We sought to determine the link between atrial fibrillation (AF) and plasma CatK levels and to investigate the expression of and therapeutic target for CatK in vivo and in vitro., Methods and Results: Plasma CatK and extracellular matrix protein peptides (intact procollagen type I of N-terminal propeptide; carboxyl-terminal telopeptide of type I collagen [ICTP]) were measured in 209 consecutive patients with AF (paroxysmal AF, 146; persistent AF, 63) and 112 control subjects. In addition, the regulation of CatK expression was investigated in vivo and vitro. Patients with AF had higher plasma CatK and ICTP levels than did control subjects. Patients with persistent AF had higher levels of plasma CatK and ICTP than did patients with paroxysmal AF. CatK was correlated with ICTP concentration and left atrial diameter in all subjects. In rabbits, superoxide production, CatK activity, fibrosis, and the levels of atrial tissue angiotensin II, angiotensin type 1 receptor, gp91phox, phospho-p38 mitogen-activated protein kinase, and CatK were greater in those with tachypacing-induced AF than in controls, and these changes were reversed with angiotensin type 1 receptor antagonist. Olmesartan and mitogen-activated protein kinase inhibitor decreased the CatK expression induced by angiotensin II in rat neonatal myocytes., Conclusions: These data indicated that increased plasma CatK levels are linked with the presence of AF. Angiotensin type 1 receptor antagonist appears to be effective in alleviating atrial fibrosis in a rabbit AF model, partly reducing angiotensin type 1 receptor-p38mitogen-activated protein kinase-dependent and -independent CatK activation, thus preventing AF.

Objective: Several studies have shown that cathepsin K (CTK) is overexpressed in osteoarthritic (OA) cartilage and subchondral bone. However, it has not been well established whether CTK expression is harmful or beneficial. We undertook this study to investigate the direct involvement of CTK in OA development using Ctsk-knockout (Ctsk(-/-)) mice in a joint instability-induced model of OA., Methods: We analyzed the natural course of the phenotype of 25-week-old Ctsk(-/-) mice. OA development was evaluated with a modified Mankin histologic score up to 8 weeks after surgery was performed to destabilize the knee in Ctsk(-/-) and Ctsk(+/+) mice. Histologic analysis was used to evaluate expression of CTK, matrix metalloproteinase 13 (MMP-13), ADAMTS-5, and tartrate-resistant acid phosphatase (TRAP) proteins in chondrocytes, synovial cells, and osteoclasts. Bone architecture was analyzed by histomorphometry., Results: Bone mineral content and bone volume were higher in Ctsk(-/-) mice at 25 weeks, whereas OA did not develop spontaneously in either Ctsk(-/-) or Ctsk(+/+) mice. In a model of destabilization-induced OA, OA progression was significantly delayed in Ctsk(-/-) mice. CTK was overexpressed in chondrocytes and synovial cells of knee joints developing OA in Ctsk(+/+) mice. MMP-13 and ADAMTS-5 were less strongly expressed in chondrocytes of Ctsk(-/-) mice, and MMP-13 was less strongly expressed in synovial cells. TRAP-positive osteoclasts were overexpressed in Ctsk(-/-) mice., Conclusion: These results indicate that CTK plays crucial direct roles in the early to intermediate stage of OA development. CTK-positive chondrocytes and synovial cells may be a possible target to prevent disease progression in OA., (Copyright © 2012 by the American College of Rheumatology.)

1. Matrix metalloproteinases (MMP) are associated with the vascular remodelling seen in atherosclerosis and aneurysm. The activation and activity of MMP-2 are regulated by the intrinsic tissue inhibitor of MMP-2 (TIMP-2). The aim of the present study was to examine whether, conversely, MMP-2 can affect the gene and protein expression of TIMP-2. 2. In the present study, we examined the mRNA and protein expression of MMP-2 and TIMP-2 in cultured smooth muscle cells (SMC) from the aortas of MMP-2(+/+) and MMP-2(-/-) mice. We also examined the roles of MMP-2 in SMC cellular events. 3. Western blotting showed that less TIMP-2 protein was present in the conditioned medium of MMP-2(-/-) SMC than in that of MMP-2(+/+) SMC. Real-time reverse transcription polymerase chain reaction analysis showed that MMP-2 deficiency reduced TIMP-2 mRNA expression in SMC. Recombinant MMP-2 enhanced the expression of TIMP-2 protein in cultured SMC from MMP-2(-/-) mice. Furthermore, a siRNA targeting MMP-2 impaired the gene and protein expression of MMP-2 in cultured SMC from MMP-2(+/+) mice. MMP-2 deficiency impaired SMC invasion, but not their proliferation, adhesion or migration. 4. Our findings suggest that MMP-2 is likely to be responsible, at least in part, for regulating TIMP-2 expression and is thus a potential target, in addition to TIMP-2, for therapeutics aimed at preventing cardiovascular remodelling in response to injury., (© 2010 Blackwell Publishing Asia Pty Ltd.)

Vascular endothelial growth factor (VEGF), also known as a vascular permeability factor (VPF), is an endothelial specific mitogen and is a potent inducer of angiogenesis. Recently it has been reported that hypoxia induces VEGF mRNA expression in various cells. Since both oxygen and glucose are required for efficient production of energy, we examined the effect of glucose deprivation on VEGF mRNA expression and VEGF protein production in U-937 (a human monocytic cell line) cells. Both the mRNA expression and secretion of VEGF increased after exposure to low glucose. Addition of L-glucose, the L-stereoisomer of D-glucose, did not prevent the up-regulation of VEGF expression. The conditioned medium from glucose-deprived cells, followed by supplementation with glucose, did not up-regulate VEGF mRNA expression in U-937 cells. The low glucose-induced VEGF mRNA expression returned to the control level after supplementation with D-glucose. Furthermore, oligomycin, a mitochondrial ATP synthase inhibitor, increased VEGF protein production. The results suggest that the up-regulation of VEGF mRNA in U-937 cells in response to glucose deprivation is not mediated by autocrine factors from the cells nor is the osmotic change of the medium mediated by the deficiency of glucose metabolism in the cells. Our results also suggest that the intracellular ATP depletion due to glucose deprivation may be one of the causes for increased VEGF mRNA expression. We speculate that local hypoglycemia may act as an essential trigger for angiogenesis through the VEGF gene expression.