Search results for "INHIBITORS"

Degradation of an alkaloid pheromone from the pale-brown chafer, Phyllopertha diversa (Coleoptera: Scarabaeidae), by an insect olfactory cytochrome P…

1999

AbstractThe pale-brown chafer, Phyllopertha diversa, utilizes an unusual alkaloid, 1,3-dimethyl-2,4-(1H,3H)-quinazolinedione, as its sex pheromone. This compound is rapidly degraded in vitro by the antennal protein extracts from this scarab beetle. Demethylation at the N-1 position and hydroxylation of the aromatic ring have been identified as the major catabolic pathways. The enzyme responsible for the pheromone degradation is membrane-bound, requires NAD(P)H for activity and is sensitive to cytochrome P450 inhibitors, such as proadifen and metyrapone. The ability to metabolize this unusual pheromone was not detected in 12 species tested, indicating that the P450 system, specific to male P…

Synthesis of Hybrid Tripeptide Peptidomimetics Containing Dehydroamino Acid and Aminophosphonic Acid in the Chain and Evaluation of Their Activity to…

2021

Synthesis of a new group of hybrid phosphonodehydropeptides composed of glycyl-(Z)-dehydrophenylalanine and structurally variable aminophosphonates alongside with investigations of their activity towards cathepsin C are presented. Obtained results suggest that the introduction of (Z)- dehydrophenylalanine residue into the short phosphonopeptide chain does induce the ordered conformation. Investigated peptides appeared to act as weak or moderate inhibitors of cathepsin C.

Phytol and Heptacosane Are Possible Tools to Overcome Multidrug Resistance in an In Vitro Model of Acute Myeloid Leukemia

2022

Drug resistance is the ability of cancer cells to gain resistance to both conventional and novel chemotherapy agents, and remains a major problem in cancer therapy. Resistance mechanisms are multifactorial and involve more strictly pharmacological factors, such as P-glycoprotein (P-gp) and biological factors such as inhibitor of apoptosis proteins (IAPs) and the nuclear factor-kappa B (NF-κB) pathway. Possible therapeutic strategies for the treatment of acute myeloid leukemia (AML) have increased in recent years; however, drug resistance remains a problem for most pa-tients. Phytol and heptacosane are the major compounds of Euphorbia intisy essential oil (EO) which were demonstrated to inhi…

Plasma PAF-acetylhydrolase in patients with coronary artery disease: results of a cross-sectional analysis.

2003

Inflammation underlies both onset and perpetuation of atherosclerosis. Plasma lipoproteins transport the platelet-activating factor-acetylhydrolase (PAF-AH) with potentially anti-inflammatory activities. Our aim was to determine whether PAF-AH activity was associated with inflammatory markers and with coronary artery disease (CAD). PAF-AH activity and a panel of inflammatory mediators were measured in plasma of 496 patients with CAD and in 477 controls; 276 patients presented with stable angina pectoris and 220 with acute coronary syndrome (ACS). Individuals within the highest quartile of PAF-AH activity had an 1.8-fold increase in CAD risk [95% confidence interval (CI), 1.01 to 3.2; P = 0.…

3-[2-(1H-Indol-3-yl)-1,3-thiazol-4-yl)-1H-pyrrolo[3,2-b]pyridine: a new series of kinase inhibitors

2009

Rac1-Regulated Endothelial Radiation Response Stimulates Extravasation and Metastasis That Can Be Blocked by HMG-CoA Reductase Inhibitors

2011

Radiotherapy (RT) plays a key role in cancer treatment. Although the benefit of ionizing radiation (IR) is well established, some findings raise the possibility that irradiation of the primary tumor not only triggers a killing response but also increases the metastatic potential of surviving tumor cells. Here we addressed the question of whether irradiation of normal cells outside of the primary tumor augments metastasis by stimulating the extravasation of circulating tumor cells. We show that IR exposure of human endothelial cells (EC), tumor cells (TC) or both increases TC-EC adhesion in vitro. IR-stimulated TC-EC adhesion was blocked by the HMG-CoA reductase inhibitor lovastatin. Glycyrr…

Rac1 protein signaling is required for DNA damage response stimulated by topoisomerase II poisons.

2012

To investigate the potency of the topoisomerase II (topo II) poisons doxorubicin and etoposide to stimulate the DNA damage response (DDR), S139 phosphorylation of histone H2AX (γH2AX) was analyzed using rat cardiomyoblast cells (H9c2). Etoposide caused a dose-dependent increase in the γH2AX level as shown by Western blotting. By contrast, the doxorubicin response was bell-shaped with high doses failing to increase H2AX phosphorylation. Identical results were obtained by immunohistochemical analysis of γH2AX focus formation, comet assay-based DNA strand break analysis, and measuring the formation of the topo II-DNA cleavable complex. At low dose, doxorubicin activated ataxia telangiectasia m…

Rationale and design of the DARWIN-T2D (DApagliflozin Real World evIdeNce in Type 2 Diabetes): A multicenter retrospective nationwide Italian study a…

2017

Background Randomized controlled trials (RCTs) in the field of diabetes have limitations inherent to the fact that design, setting, and patient characteristics may be poorly transferrable to clinical practice. Thus, evidence from studies using routinely accumulated clinical data are increasingly valued. Aims We herein describe rationale and design of the DARWIN-T2D (DApagliflozin Real World evIdeNce in Type 2 Diabetes), a multicenter retrospective nationwide study conducted at 50 specialist outpatient clinics in Italy and promoted by the Italian Diabetes Society. Data synthesis The primary objective of the study is to describe the baseline clinical characteristics (particularly HbA1c) of pa…

HMG-CoA reductase inhibitors (statins) as anticancer drugs (Review)

2005

Apart from their lipid lowering activity, HMG-CoA reductase inhibitors (statins) impair numerous cellular functions associated with metastasis, e.g. gene expression, angiogenesis, cell adhesion, cell motility and invasiveness. Furthermore, statins have impact on apoptotic cell death and modulate cellular susceptibility to cell killing by anticancer drugs and ionizing radiation. Part of the effects provoked by statins are due to the inhibition of the prenylation of low molecular weight GTPases, in particular Ras and Rho, which play key roles in signaling evoked by stimulation of cell surface receptors. C-terminal lipid modification of Ras/Rho GTPases is essential for their correct intracellu…

Rho GTPases are over-expressed in human tumors.

1999

Small GTPases of the Rho family are involved in the regulation of a variety of cellular processes, such as the organization of the microfilamental network, cell-cell contact and malignant transformation. To address the question of whether Rho proteins are involved in carcinogenesis in man, we compared their expression in tumors from colon, breast and lung with that of the corresponding normal tissue originating from the same patient. As shown by Rho-specific 32P-ADP-ribosylation, as well as Western-blot analysis, the amount of RhoA protein was largely increased in all 3 types of tumors tested. The most dramatic differences in the expression of Rho GTPases were observed in breast tissue. All…