Effects of the FGF receptor-1 inhibitor, infigratinib, with or without sildenafil, in experimental pulmonary arterial hypertension.

BACKGROUND AND PURPOSE: Pulmonary arterial hypertension (PAH) is a progressive disease associated with high morbidity and mortality, despite advances in medical therapy. We compared the effects of infigratinib (NVP-BGJ398), a new FGF receptor-1 inhibitor, with or without the PDE-5 inhibitor sildenafil, on vascular function and remodelling as well as on gene expression of signal transducers for receptors of TGF-ß (Smads-1/2/4) and transcription factor of endothelial-mesenchymal transition (Twist-1) in established experimental PAH. Types I and III pro-collagen and TGF-ß expressions in lung fibroblasts were analysed in vitro after the different treatments. EXPERIMENTAL APPROACH: PAH was induced in male Wistar rats with monocrotaline. 14 days later, treatments [sildenafil (SIL), infigratinib (INF) or their combination (SIL+INF)] were given for another 14 days. On Day 28, echocardiography and haemodynamic assays were performed, and lungs and pulmonary vessels were removed for analysis by histology, immunohistochemistry and RT-PCR. Fibroblasts prepared from PAH lungs were also analysed for TGF-ß and pro-collagen. KEY RESULTS: Only the combination of infigratinib and sildenafil significantly improved right ventricular systolic pressure and vascular remodelling parameters (right ventricular hypertrophy, smooth muscle α-actin, vessel wall thickness, and vascular collagen content). Infigratinib may act by reducing gene expression of Smads-1/4 and Twist-1 in lung tissue, as well as TGF-ß and types I and III pro-collagen in lung fibroblasts. CONCLUSIONS AND IMPLICATIONS: In this model of monocrotaline-induced PAH, the combination of the new inhibitor of FGF receptor-1, infigratinib, and sildenafil effectively improved haemodynamics and decreased vascular remodelling.

Structural and energetic basis for the inhibitory selectivity of both catalytic domains of dimeric HDAC6.

HDAC6 is a protein involved in cancer, neurodegenerative disease and inflammatory disorders. To date, the full three-dimensional (3D) structure of human HDAC6 has not been elucidated; however, there are some experimental 3D structural homologs to HDAC6 that can be used as templates. In this work, we utilized molecular modeling procedures to model both of the catalytic domains of HDAC6 connected by the linker region where DMB region is placed. Once the 3D structure of human HDAC6 was obtained, it was structurally evaluated and submitted to docking and molecular dynamic (MD) simulations along with Molecular Mechanics/Generalized Born Surface Area (MM/GBSA) method to explore the stability and the binding free energy properties of the HDAC6-ligand complexes. In addition, its structural and energetic behavior was explored with each one of the catalytic domains in the molecular recognition of six selective HDAC6 inhibitors, HPOB, CAY10603, Nexturastat, Rocilinostat, Tubacin and Tubastatin A for DD2, and with the so-called 9-peptide which is DD1-HDAC6 selective substrate. The use of the whole system (DD1-DMB-DD2) showed a tendency toward the ligand affinity of DD2, CAY10603> Tubacin > Rocilinostat > Nexturastat > HPOB > Tubastatin > 9-peptide, which is in line with experimental reports. However, 9-peptide showed a higher affinity for DD1, which agrees with experimental reports elsewhere. Principal component analysis provided important information about the structural changes linked to the molecular recognition process, whereas per-residue decomposition analysis revealed the energetic contribution of the key residues in the molecular binding and structural characteristics that could assist in drug design.

The anti-hepatocellular carcinoma cell activity by a novel mTOR kinase inhibitor CZ415.

Dysregulation of mammalian target of rapamycin (mTOR) in hepatocellular carcinoma (HCC) represents a valuable treatment target. Recent studies have developed a highly-selective and potent mTOR kinase inhibitor, CZ415. Here, we showed that nM concentrations of CZ415 efficiently inhibited survival and induced apoptosis in HCC cell lines (HepG2 and Huh-7) and primary-cultured human HCC cells. Meanwhile, CZ415 inhibited proliferation of HCC cells, more potently than mTORC1 inhibitors (rapamycin and RAD001). CZ415 was yet non-cytotoxic to the L02 human hepatocytes. Mechanistic studies showed that CZ415 disrupted assembly of mTOR complex 1 (mTORC1) and mTORC2 in HepG2 cells. Meanwhile, activation of mTORC1 (p-S6K1) and mTORC2 (p-AKT, Ser-473) was almost blocked by CZ415. In vivo studies revealed that oral administration of CZ415 significantly suppressed HepG2 xenograft tumor growth in severe combined immuno-deficient (SCID) mice. Activation of mTORC1/2 was also largely inhibited in CZ415-treated HepG2 tumor tissue. Together, these results show that CZ415 blocks mTORC1/2 activation and efficiently inhibits HCC cell growth in vitro and in vivo.

Pre-anthesis CPPU low dosage application increases 'Hayward' kiwifruit weight without affecting the other qualitative and nutritional characteristics.

In 2008, in Central Italy, a low dosage of CPPU solution, 4 µL L(-1) (6 hL/ha), was sprayed on the canopy of vines of 'Hayward' kiwifruit, at the "break of sepals", about one week before anthesis, to study its effects on fruit weight/size and on qualitative and nutritional characteristics. At harvest, CPPU, with respect to control, significantly increased the fresh weight by about 12% (+12.6 g fruit(-1)) and consequently the yield per vine, without affecting fruit shape, firmness, dry matter (%), total soluble solids, glucose, fructose, sucrose, starch, citrate, malate, vitamin C and soluble and insoluble oxalic acid. After 3 months of storage, CPPU-treated kiwifruits and the control fruit showed no difference in dry matter content, fruit firmness and total soluble solids. The results indicate that a low dosage of CPPU applied in pre-anthesis can improve fruit weight/size without any negative effect on fruit qualitative and nutritional characteristics.

Chlorbromuron urea herbicide removal by electro-Fenton reaction in aqueous effluents.

The removal of low concentration of chlorbromuron herbicide in aqueous systems was carried out by electro-Fenton process comprised of three-electrode divided and undivided cell with a reticulated vitreous carbon cathode and platinum anode. The electro-Fenton was also carried out in a two-electrode undivided cell in which ferrous ion forms from a sacrificial iron anode. It was observed that the total organic carbon (TOC) removal efficiency was influenced by the cell voltage, the pH of the solution and initial herbicide concentration during the electro-Fenton treatment with a stainless steel anode. The Fe(2+)/Fe(3+) activity in the Fenton chemistry (regardless if it is hydroxyl radical or ferryl ion) was improved by the electrochemical catalysis leading to a TOC analysis below the detection limit (0.2 mg l(-1)) corresponding to a TOC removal over 98%. It was found that TOC removal during chlorbromuron degradation followed apparent first order kinetics. The rate constant was increased by decreasing the initial concentration of chlorbromuron.

Synthesis and evaluation of new antimalarial phenylurenyl chalcone derivatives.

Phenylurenyl chalcone derivatives have been synthesized and tested as inhibitors of in vitro development of a chloroquine-resistant strain of Plasmodium falciparum, activity of the cysteine protease falcipain-2, in vitro globin hydrolysis, beta-hematin formation, and murine Plasmodium berghei malaria. The most active antimalarial compound was 1-[3'-N-(N'-phenylurenyl)phenyl]-3(3,4,5-trimethoxyphenyl)-2-propen-1-one 49, with an IC(50) of 1.76 microM for inhibition of P. falciparum development. Results suggest that chalcones exert their antimalarial activity via multiple mechanisms.

Multianalyte determination of different classes of pesticides (acidic, triazines, phenyl ureas, anilines, organophosphates, molinate and propanil) by liquid chromatography-electrospray-tandem mass spectrometry.

This work describes the optimization of a liquid chromatography-electrospray-tandem mass spectrometry (LC-ESI-MS-MS) method for the multianalyte determination of twenty pesticides, selected based on current regulations and extent of use. Chromatographic separation was carried out on a Purospher STAR RP-18e column using gradient acetonitrile-water as mobile phase. Triazines, phenylureas, organophosphates, anilines, and molinate were determined in the positive ionization mode, and acidic pesticides and propanil in the negative ion mode. Two different precursor ion-product ion transitions were selected for each analyte and monitored under time scheduled multiple reaction monitoring (MRM) conditions. The optimized method was shown to be linear in the range 1 to 1000 ng/mL with correlation coefficients higher than 0.99 for all but one (diazinon) of the analytes, very sensitive (with limits of detection between 0.010 and 4.528 ng/mL), and repeatable (with relative standard deviations, calculated from the replicate analysis of standard mixtures, lower than 14%). The present work was also devoted to the elucidation of the structures of the principal fragment ions obtained after collision-induced dissociation of the pesticides investigated, an aspect often overlooked in the literature.