Human omentin-1 reduces vascular insulin resistance and hypertension in Otsuka Long-Evans Tokushima Fatty rats.

PURPOSE: Hypertension is one of the major risk factors for renal failure and cardiovascular diseases, and is caused by various abnormalities including the contractility of blood vessels. Otsuka Long-Evans Tokushima Fatty (OLETF) rats, which mimic human type 2 diabetes, are frequently used to study obesity-induced insulin resistance (IR) and hypertension. Human omentin-1 is one of the recently identified adipocytokines. We previously demonstrated that human omentin-1 not only caused vasodilation in rat isolated blood vessels, but also prevented inflammatory responses, a possible mechanism relating IR, in human vascular endothelial cells. Taken together, we hypothesized that human omentin-1 may reduce obesity-induced IR and hypertension in OLETF rats. METHODS: OLETF rats were intraperitoneally administered with human omentin-1 for 7 days. RESULTS: Human omentin-1 had no influence on overweight, hyperglycemia, urinary glucose extraction, hyperinsulinemia, and systemic IR in OLETF rats. Human omentin-1 decreased systolic blood pressure in OLETF rats. The measurement of isometric contraction revealed that human omentin-1 had no influence on the agonist-induced contractile and relaxant responses in isolated thoracic aorta from OLETF rats. However, the relaxant response mediated by human insulin was converted into the contractile response in thoracic aorta from OLETF rats, which was prevented by human omentin-1. The Western blotting revealed that human omentin-1 improved the decrease in endothelial nitric oxide synthase activation in isolated thoracic aorta from OLETF rats. CONCLUSION: In summary, we for the first time revealed that human omentin-1 partly reduces vascular IR and thereby inhibits hypertension in OLETF rats.

Combined therapeutic effect of YHO-1701 with PD-1 blockade is dependent on natural killer cell activity in syngeneic mouse models.

The signal transducer and activator of transcription 3 (STAT3) signaling pathway is a key mediator of cancer cell proliferation, survival, and invasion. We discovered YHO-1701 as a small molecule inhibitor of STAT3 dimerization and demonstrated its potent anti-tumor activity using xenograft mouse models as monotherapy and combination therapy with molecular targeted drugs. STAT3 is also associated with cancer immune tolerance; therefore, we used the female CT26 syngeneic mouse model to examine the effect of combining YHO-1701 administration with PD-1/PD-L1 blockade. Pretreatment of the mice with YHO-1701 before starting anti-PD-1 antibody administration resulted in a significant therapeutic effect. In addition, the effect of monotherapy and combination treatment with YHO-1701 was significantly abolished by depleting natural killer (NK) cell activity. YHO-1701 was also found to restore the activity of mouse NK cells under inhibitory conditions in vitro. Furthermore, this combination therapy significantly inhibited tumor growth in an immunotherapy-resistant model of murine CMS5a fibrosarcoma. These results suggest that the combination of YHO-1701 with PD-1/PD-L1 blockade might be a new candidate for cancer immunotherapy involving the enhancement of NK cell activity in the tumor microenvironment.

Human Omentin-1 Administration Ameliorates Hypertensive Complications without Affecting Hypertension in Spontaneously Hypertensive Rats.

Hypertension is one of the major risk factors for cardiovascular diseases and is caused by various abnormalities including the contractility of blood vessels. Spontaneously hypertensive rats (SHR), whose systemic blood pressure increases with aging, are a frequently used animal model for investigating essential hypertension and related complications in humans due to the damage of several organs. Human omentin-1 is an adipocytokine consisting of 313 amino acids. Serum omentin-1 levels decreased in hypertensive patients compared with normotensive controls. Furthermore, omentin-1 knockout mice showed elevated blood pressure and impaired endothelial vasodilation. Taken together, we hypothesized that adipocytokine, human omentin-1 may improve the hypertension and its complications including heart and renal failure in the aged SHR (65-68-weeks-old). SHR were subcutaneously administered with human omentin-1 (18 µg/kg/day, 2 weeks). Human omentin-1 had no effect on body weight, heart rate, and systolic blood pressure in SHR. The measurement of isometric contraction revealed that human omentin-1 had no influence on the enhanced vasocontractile or impaired vasodilator responses in the isolated thoracic aorta from SHR. On the other hand, human omentin-1 tended to improve left ventricular diastolic failure and renal failure in SHR. In summary, human omentin-1 tended to improve hypertensive complications (heart and renal failure), while it had no influence on the severe hypertension in the aged SHR. The further study of human omentin-1 may lead to the development of therapeutic agents for hypertensive complications.

Plasmid-based and -free methods using CRISPR/Cas9 system for replacement of targeted genes in Colletotrichum sansevieriae.

The CRISPR-Cas9 system has a potential for wide application in organisms that particularly present low homologous integration rates. In this study, we developed three different methods using this system to replace a gene through homology-directed repair in the plant pathogenic fungus Colletotrichum sansevieriae, which has a low recombination frequency. The gene encoding scytalone dehydratase was used as the target so that mutants can be readily distinguished owning to a lack of melanin biosynthesis. First, we performed a plasmid-based method using plasmids containing a Cas9 expression cassette and/or a single-guide RNA (sgRNA) under the control of the endogenous U6 snRNA promoter, and 67 out of 69 (97.1%) transformants exhibited a melanin-deficient phenotype with high efficiency. Second, we performed a transformation using a Cas9 protein/sgRNA complex and obtained 23 out of 28 (82.1%) transformants. Lastly, we developed a hybrid system combining a Cas9 protein and donor DNA-sgRNA expression plasmid, which yielded 75 out of 84 (89.2%) transformants. This system was also applicable to four other genes at different loci of the fungus. This is the first study to establish a CRISPR/Cas9 gene replacement system in Colletotrichum spp. and it presents a potential application for a broad range of use in other species of the genus.

Functional characterization of unique enzymes in Xanthomonas euvesicatoria related to degradation of arabinofurano-oligosaccharides on hydroxyproline-rich glycoproteins.

In this study, we clarified the functions of three uncharacterized enzymes, XCV2724, XCV2728, and XCV2729, in Xanthomonas euvesicatoria, the causal agent of bacterial spot of tomato and pepper. The genes corresponding to the three enzymes are homologs of hypBA1, hypBA2, and hypAA from Bifidobacterium longum and are unique to Xanthomonas spp. among plant pathogenic bacteria. Functional characterization of the recombinant enzymes expressed using microbial systems revealed that they degrade the arabinofurano-oligosaccharides present on hydroxyproline (Hyp)-rich glycoproteins (HRGPs) such as extensin and solanaceous lectins in plant cell walls. These enzymes work coordinately to degrade the oligosaccharides. First, XeHypAA (XCV2728), belonging to the glycoside hydrolase (GH) 43 family, releases L-arabinose from L-arabinofuranose (Araf)-α1,3-Araf-ß1,2-Araf-ß1,2-Araf-ß-Hyp (Ara4-Hyp), cleaving its α1,3 bond; second, XeHypBA2 (XCV2729), belonging to the GH121 family, releases the disaccharide Araf-ß1,2-Araf from Araf-ß1,2-Araf-ß1,2-Araf-ß-Hyp (Ara3-Hyp); finally, XeHypBA1 (XCV2724), belonging to GH family 127, releases L-arabinose from Araf-ß-Hyp (Ara-Hyp). In summary, the main oligosaccharide structure of Ara4-Hyp on the HRGPs is degraded to Ara3-Hyp, then to Ara-Hyp, and finally to Ara monosaccharides by the action of these three enzymes. HRGPs containing oligosaccharide substrates have been reported to contribute to plant defense, and interestingly, the promoter region of the operon (xehypBA2 and xehypAA) contains the plant-inducible promoter box for binding the regulator protein HrpX involved in pathogenicity. We then analyzed the expression level of the operon gene in hrp-inducing medium and in plants and constructed gene-deletion mutants. However, although the operon was evidently upregulated by HrpX, three single-gene deletion mutants (ΔxehypBA1, ΔxehypBA2, ΔxehypAA) and even a triple-gene deletion mutant (ΔxehypBA1-BA2-AA) remained pathogenic, and had no effect on nonhost resistance, either, indicating that these three enzymes are not involved in either pathogenicity or nonhost resistance reactions. This is the first report of enzymes in plant pathogenic bacteria that catalyze the degradation of Hyp-linked-L-arabinofuranosides in plant cell walls.

Visceral adipose tissue-derived serine protease inhibitor prevents the development of monocrotaline-induced pulmonary arterial hypertension in rats.

Visceral adipose tissue-derived serine protease inhibitor (vaspin), a recently identified adipocytokine, inhibits inflammation, migration, and apoptosis of vascular cells. We have recently demonstrated that chronic administration of vaspin to spontaneously hypertensive rats partly prevents systemic hypertension through inhibiting inflammation and remodeling of vascular wall. Pulmonary arterial (PA) hypertension (PAH) is caused by PA remodeling, contractile dysfunction, and inflammatory responses. We tested the hypothesis that vaspin could prevent development of PAH in animal model. PAH was induced by a single intraperitoneal injection of monocrotaline (MCT; 60 mg/kg), and vaspin (1 µg/kg/day) was treated for 14 days from the day of MCT injection. PA pressure and contractile reactivity of isolated intrapulmonary artery (IPA) were measured. Using isolated lung tissues, IPA wall thickness and fibrosis, matrix metalloproteinase (MMP) activity, and reactive oxygen species (ROS) generation were examined. For in vitro study, after rat PA smooth muscle cells (PASMCs) were stimulated with interleukin (IL)-1ß (10 ng/ml, 48 h) in the presence of vaspin (5 ng/ml, 30 min), MMP activity and ROS generation were examined. Vaspin significantly attenuated MCT-induced rise in PA pressure, while it had no influence on impairment of relaxing function in IPA. Vaspin significantly prevented MCT-induced IPA fibrosis but not hypertrophy. Vaspin significantly inhibited MCT-induced ROS generation and MMP-2 activation in lung tissues. In addition, vaspin significantly inhibited IL-1ß-induced ROS generation and MMP-2 activation in PASMCs. In summary, we for the first time demonstrate that vaspin prevents MCT-induced PAH at least in part via inhibiting ROS/MMP-2/fibrosis pathway.

Vasculo-protective effect of BMS-309403 is independent of its specific inhibition of fatty acid-binding protein 4.

Fatty acid-binding protein (FABP) 4 is an adipocytokine mainly expressed in adipocyte and macrophage. Blood FABP4 is related not only to metabolic disorders including insulin resistance and atherosclerosis but also increased blood pressure. We tested the hypothesis that FABP4 plays roles in pathogenesis of hypertension development including proliferation, migration, and inflammation of vascular smooth muscle cells (SMCs) as well as contractile reactivity. FABP4 alone had no influence on proliferation, migration, and inflammation of rat mesenteric arterial SMCs, while it significantly enhanced smooth muscle contraction and increases of systolic blood pressure (SBP) induced by noradrenaline (NA). BMS-309403, an FABP4 inhibitor, significantly inhibited platelet-derived growth factor-BB-induced DNA synthesis and migration via preventing p38 and HSP27 activation. Further, BMS-309403 significantly inhibited tumor necrosis factor-α-induced expression of vascular cell adhesion molecule-1 and monocyte chemotactic protein-1 as well as monocyte adhesion via preventing NF-κB activation. Interestingly, SMCs do not express FABP4. Long-term treatment of spontaneously hypertensive rats (SHR) with BMS-309403 significantly inhibited impaired relaxation in isolated mesenteric arteries and left ventricular hypertrophy, while it had no influence on SBP. We for the first time showed that FABP4 acutely enhances NA-induced increases of SBP possibly through the enhancement of peripheral arterial contractility. BMS-309403 prevents proliferation, migration, and inflammatory responses of SMCs, although exogenous application of FABP4 has no influence on the cellular responses. Furthermore, we demonstrated that long-term treatment with BMS-309403 partially improves the pathological conditions of SHR. These results indicate that BMS-309403 would be useful for developing a new pharmacotherapeutic agent against obesity-associated hypertension and complications.

Phase I/II study of docetaxel combined with resminostat, an oral hydroxamic acid HDAC inhibitor, for advanced non-small cell lung cancer in patients previously treated with platinum-based chemotherapy.

Objectives To determine the recommended dose and efficacy/safety of docetaxel combined with resminostat (DR) in non-small cell lung cancer (NSCLC) patients with previous platinum-based chemotherapy. Materials and Methods A multicenter, open-label, phase I/II study was performed in Japanese patients with stage IIIB/IV or recurrent NSCLC and prior platinum-based chemotherapy. The recommended phase II dose was determined using a standard 3 + 3 dose design in phase I part. Resminostat was escalated from 400 to 600 mg/day and docetaxel fixed at 75 mg/m2. In phase II part, the patients were randomly assigned to docetaxel alone (75 mg/m2) or DR therapy. Docetaxel was administered on day 1 and resminostat on days 1-5 in the DR group. Treatment was repeated every 21 days until progression or unacceptable toxicity. The primary endpoint was progression-free survival (PFS). Results A total of 117 patients (phase I part, 9; phase II part, 108) were enrolled. There was no dose-limiting toxicity in phase I part; the recommended dose for resminostat was 600 mg/day with 75 mg/m2 of docetaxel. In phase II part, median PFS (95% confidence interval [CI]) was 4.2 (2.8-5.7) months with docetaxel group and 4.1 (1.5-5.4) months with DR group (hazard ratio [HR]: 1.354, 95% CI: 0.835-2.195; p = 0.209). Grade ≥ 3 adverse events significantly more common with DR group than docetaxel group were leukopenia, febrile neutropenia, thrombocytopenia, and anorexia. Conclusion In Japanese NSCLC patients previously treated with platinum-based chemotherapy, DR therapy did not improve PFS compared with docetaxel alone and increased toxicity.