Search results for "lcsh:RM1-950"
showing 10 items of 252 documents
Oridonin Targets Multiple Drug-Resistant Tumor Cells as Determined by in Silico and in Vitro Analyses
2018
Drug resistance is one of the main reasons of chemotherapy failure. Therefore, overcoming drug resistance is an invaluable approach to identify novel anticancer drugs that have the potential to bypass or overcome resistance to established drugs and to substantially increase life span of cancer patients for effective chemotherapy. Oridonin is a cytotoxic diterpenoid isolated from Rabdosia rubescens with in vivo anticancer activity. In the present study, we evaluated the cytotoxicity of oridonin toward a panel of drug-resistant cancer cells overexpressing ABCB1, ABCG2, or ΔEGFR or with a knockout deletion of TP53. Interestingly, oridonin revealed lower degree of resistance than the control dr…
Drug Retention Rate and Predictive Factors of Drug Survival for Interleukin-1 Inhibitors in Systemic Juvenile Idiopathic Arthritis.
2019
Introduction: The advent of biologic agents has revolutionized therapeutic approaches in systemic juvenile idiopatic arthritis (sJIA) as their introduction has been shown to modify disease course and improve overall outcomes, particularly when initiated early. Few studies have reported the drug retention rate (DRR) of biologic drugs in JIA, and none of them has specifically investigated the DRR of interleukin (IL)-1 inhibitors on sJIA. Objectives: The primary aim of the study was to examine the overall DRR of IL-1 blockers in sJIA patients. Secondary aims of our study were to: (i) explore the influence of biologic line of treatment, adverse events (AEs), type of anti-IL-1 agent and the conc…
Beneficial Role of Exercise in the Modulation of
2021
Duchenne muscular dystrophy (DMD) is an X-linked recessive progressive lethal disorder caused by the lack of dystrophin, which determines myofibers mechanical instability, oxidative stress, inflammation, and susceptibility to contraction-induced injuries. Unfortunately, at present, there is no efficient therapy for DMD. Beyond several promising gene- and stem cells-based strategies under investigation, physical activity may represent a valid noninvasive therapeutic approach to slow down the progression of the pathology. However, ethical issues, the limited number of studies in humans and the lack of consistency of the investigated training interventions generate loss of consensus regarding …
Pharmacokinetics and Pharmacodynamics of a 13-mer LNA-inhibitor-miR-221 in Mice and Non-human Primates
2016
Locked nucleic acid (LNA) oligonucleotides have been successfully used to efficiently inhibit endogenous small noncoding RNAs in vitro and in vivo. We previously demonstrated that the direct miR-221 inhibition by the novel 13-mer LNA-i-miR-221 induces significant antimyeloma activity and upregulates canonical miR-221 targets in vitro and in vivo. To evaluate the LNA-i-miR-221 pharmacokinetics and pharmacodynamics, novel assays for oligonucleotides quantification in NOD.SCID mice and Cynomolgus monkeys (Macaca fascicularis) plasma, urine and tissues were developed. To this aim, a liquid chromatography/mass spectrometry method, after solid-phase extraction, was used for the detection of LNA-i…
Increased Motor-Impairing Effects of the Neuroactive Steroid Pregnanolone in Mice with Targeted Inactivation of the GABAA Receptor γ2 Subunit in the …
2016
Endogenous neurosteroids and neuroactive steroids have potent and widespread actions on the brain via inhibitory GABAA receptors. In recombinant receptors and genetic mouse models their actions depend on the α, β, and δ subunits of the receptor, especially on those that form extrasynaptic GABAA receptors responsible for non-synaptic (tonic) inhibition, but they also act on synaptically enriched γ2 subunit-containing receptors and even on αβ binary receptors. Here we tested whether behavioral sensitivity to the neuroactive steroid agonist 5β-pregnan-3α-ol-20-one is altered in genetically engineered mouse models that have deficient GABAA receptor-mediated synaptic inhibition in selected neuro…
Artemisinin Derivatives Target Topoisomerase 1 and Cause DNA Damage in Silico and in Vitro
2017
DNA topoisomerases 1 and 2 are enzymes that maintain DNA topology and play important essential genome functions, including DNA replication and transcription. Aberrant topoisomerases cause genome instability and a wide range of diseases, cancer in particular. Both Topo 1 and 2 are the targets of valuable anticancer drugs, such as camptothecin. It has been previously shown that artemisinin, a sesquiterpene lactone from Artemisia annua L. also known as qinghaosu, possesses anti-cancer effects and one of its derivatives, artesunate inhibits Topo 2. In this study, we evaluated artemisinin and 40 derivatives as potential Topo 1 inhibitors at first by in silico molecular docking analyses. Five com…
Hepatoprotective Effect of Steroidal Glycosides From Dioscorea villosa on Hydrogen Peroxide-Induced Hepatotoxicity in HepG2 Cells
2018
Dioscorea villosa, commonly known as “Wild Yam” and native to North America, is well documented for its pharmacological properties due to the presence of steroidal glycosides. However, the hepatoprotective potential of these compounds has not been studied so far. The present investigation was aimed to study the hepatoprotective effect of the steroidal glycosides from D. villosa against H2O2, a known hepatotoxin, in human liver cell line (HepG2). Cytotoxicity assessment was carried out in cells exposed to various concentrations (10–50 μM) of compounds for 24 h using MTT assay and morphological changes. All tested compounds were known and among them, spirostans (zingiberensis saponin I, diosc…
Considerations for an in vitro, cell-based testing platform for detection of adverse drug-induced inotropic effects in early drug development. Part 1…
2019
Drug-induced effects on cardiac contractility can be assessed through the measurement of the maximal rate of pressure increase in the left ventricle (LVdP/dtmax) in conscious animals, and such studies are often conducted at the late stage of preclinical drug development. Detection of such effects earlier in drug research using simpler, in vitro test systems would be a valuable addition to our strategies for identifying the best possible drug development candidates. Thus, testing platforms with reasonably high throughput, and affordable costs would be helpful for early screening purposes. There may also be utility for testing platforms that provide mechanistic information about how a given d…
Berberine Mediated Positive Inotropic Effects on Rat Hearts via a Ca2+-Dependent Mechanism
2020
Previous studies showed that berberine, an alkaloid from Coptis Chinensis Franch, might exert a positive inotropic effect on the heart. However, the underlying mechanisms were unclear. Here, we reported that berberine at 10-20 µM increased the left ventricular (LV) developed pressure and the maximal rate of the pressure rising, and it increased the maximal rate of the pressure descending at 20 µM in Langendorff-perfused isolated rat hearts. These effects diminished with the concentration of berberine increasing to 50 µM. In the concentration range of 50-300 µM, berberine increased the isometric tension of isolated left ventricular muscle (LVM) strips with or without electrical stimulations,…
Redox Status, Dose and Antioxidant Intake in Healthcare Workers Occupationally Exposed to Ionizing Radiation
2020
The purpose of this study was to evaluate the relationship between blood redox status, dose and antioxidant dietary intake of different hospital staff groups exposed to low doses of ionizing radiation (LDIR) (Interventional Radiology and Cardiology, Radiation Oncology, and Nuclear Medicine) and non-exposed. Personal dose equivalent (from last year and cumulative), plasma antioxidant markers (total antioxidant capacity, extracellular superoxide dismutase activity, and glutathione/oxidized glutathione ratio), oxidative stress markers (nitrites and nitrates, and lipid peroxidation) and dietary intake (antioxidant capacity using ORAC values) were collected and analyzed from 28 non-exposed healt…