ABSTRACT
The present work describes the anticancer activity of Ophiobolin A isolated from the endophytic fungus Bipolaris setariae. Ophiobolin A was isolated using preparative HPLC and its structure was confirmed by HRMS, (1)H NMR, (13)C NMR, COSY, DEPT, HSQC and HMBC. It inhibited solid and haematological cancer cell proliferation with IC50 of 0.4-4.3 µM. In comparison, IC50 against normal cells was 20.9 µM. It was found to inhibit the phosphorylation of S6 (IC50 = 1.9 ± 0.2 µM), ERK (IC50 = 0.28 ± 0.02 µM) and RB (IC50 = 1.42 ± 0.1 µM), the effector proteins of PI3K/mTOR, Ras/Raf/ERK and CDK/RB pathways, respectively. It induced apoptosis and inhibited cell cycle progression in MDA-MB-231 cancer cells with concomitant inhibition of signalling proteins. Thus, this study reveals that anticancer activity of Ophiobolin A is associated with simultaneous inhibition of multiple oncogenic signalling pathways namely PI3K/mTOR, Ras/Raf/ERK and CDK/RB.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Sesterterpenes/pharmacology , Antineoplastic Agents, Phytogenic/isolation & purification , Apoptosis/drug effects , Ascomycota/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Chromatography, High Pressure Liquid , Drug Screening Assays, Antitumor , Endophytes/chemistry , Humans , Inhibitory Concentration 50 , Molecular Structure , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation/drug effects , Sesterterpenes/isolation & purification , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/metabolismABSTRACT
NFAT-133 is an aromatic compound with cinammyl alcohol moiety, isolated from streptomycetes strain PM0324667. We have earlier reported that NFAT-133 increases insulin stimulated glucose uptake in L6 myotubes using a PPARγ independent mechanism and reduces plasma or blood glucose levels in diabetic mice. Here we investigated the effects of NFAT-133 on cellular signaling pathways leading to glucose uptake in L6 myotubes. Our studies demonstrate that NFAT-133 increases glucose uptake in a dose- and time-dependent manner independent of the effects of insulin. Treatment with Akti-1/2, wortmannin and increasing concentrations of insulin had no effect on NFAT-133 mediated glucose uptake. NFAT-133 induced glucose uptake is completely mitigated by Compound C, an AMPK inhibitor. Further, the kinases upstream of AMPK activation namely; LKB-1 and CAMKKß are not involved in NFAT-133 mediated AMPK activation nor does the compound NFAT-133 have any effect on AMPK enzyme activity. Further analysis confirmed that NFAT-133 indirectly activates AMPK by reducing the mitochondrial membrane potential and increasing the ratio of AMP:ATP.
Subject(s)
AMP-Activated Protein Kinases/metabolism , Glucose/metabolism , Muscle Fibers, Skeletal/cytology , Muscle Fibers, Skeletal/metabolism , Pentanols/pharmacology , Pentanones/pharmacology , Signal Transduction/drug effects , AMP-Activated Protein Kinases/antagonists & inhibitors , Adenosine Monophosphate/metabolism , Adenosine Triphosphate/metabolism , Animals , Biological Transport/drug effects , Cell Line , Dose-Response Relationship, Drug , Enzyme Activation/drug effects , GTPase-Activating Proteins/metabolism , Glucose Transporter Type 4/metabolism , Humans , Insulin/pharmacology , Membrane Potential, Mitochondrial/drug effects , Mice , Muscle Fibers, Skeletal/drug effects , Phosphorylation/drug effects , Protein Kinase Inhibitors/pharmacology , Rats , Time FactorsABSTRACT
Nitric oxide-releasing non-steroidal anti-inflammatory drugs (NO-NSAIDs) are gaining attention as potentially gastric-sparing NSAIDs. Herein, we report a novel class of '1-(nitrooxy)ethyl ester' group-containing NSAIDS as efficient NO releasing 'true' prodrugs of aspirin and naproxen. While an aspirin prodrug exhibited comparable oral bioavailability and antiplatelet activity (i.e., TXB2 inhibition) to those of aspirin, a naproxen prodrug exhibited better bioavailability than naproxen. These promising NO-NSAIDs protected experimental rats from gastric damage. We therefore believe that these promising NO-NSAIDs could represent a new class of potentially 'Safe NSAIDs' for the treatment of arthritic pain, inflammation and cardiovascular disorders in the case of NO-aspirin.
Subject(s)
Aspirin/analogs & derivatives , Naproxen/analogs & derivatives , Nitrates/chemistry , Prodrugs/chemistry , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/toxicity , Area Under Curve , Aspirin/chemistry , Aspirin/pharmacokinetics , Aspirin/pharmacology , Aspirin/toxicity , Blood Platelets/drug effects , Blood Platelets/enzymology , Cyclooxygenase 1/chemistry , Cyclooxygenase 1/metabolism , Cyclooxygenase 2/chemistry , Cyclooxygenase 2/metabolism , Drug Design , Drug Stability , Gastric Mucosa/drug effects , Half-Life , Humans , Naproxen/chemistry , Naproxen/pharmacokinetics , Naproxen/pharmacology , Naproxen/toxicity , Nitrates/pharmacokinetics , Nitrates/pharmacology , Nitrates/toxicity , Nitric Oxide/metabolism , Platelet Aggregation Inhibitors/chemistry , Platelet Aggregation Inhibitors/pharmacokinetics , Platelet Aggregation Inhibitors/pharmacology , Platelet Aggregation Inhibitors/toxicity , Prodrugs/pharmacokinetics , Prodrugs/pharmacology , Prodrugs/toxicity , ROC Curve , Rats , Rats, Sprague-Dawley , Thromboxane B2/metabolismABSTRACT
Astragalin was isolated for the first time along with (-)hinokinin, aristolactam I and aristolochic acids (I & II) from the extracts of Aristolochia indica L. using a new, efficient preparative HPLC method. A reversed-phase HPLC method of analysis was developed to analyse the isolated compounds. The crude extracts and the isolated compounds were tested for their anti-inflammatory potential. We report here for the first time the anti-inflammatory effects of (-)hinokinin and aristolactam I against IL-6 (IC50 = 20.5 ± 0.5 and 52 ± 8 µM) and TNFα (IC50 = 77.5 ± 27.5 and 116.8 ± 83.25 µM), respectively. (-)Hinokinin exerted its anti-inflammatory effects via NFκB-dependent mechanism whereas aristolactam I may be effective via a mechanism independent of NFκB.
Subject(s)
4-Butyrolactone/analogs & derivatives , Aristolochia/chemistry , Aristolochic Acids/isolation & purification , Aristolochic Acids/pharmacology , Dioxoles/isolation & purification , Dioxoles/pharmacology , Kaempferols/isolation & purification , Kaempferols/pharmacology , Lignans/isolation & purification , Lignans/pharmacology , 4-Butyrolactone/chemistry , 4-Butyrolactone/isolation & purification , 4-Butyrolactone/pharmacology , Anti-Inflammatory Agents , Aristolochic Acids/chemistry , Benzodioxoles , Chromatography, High Pressure Liquid , Dioxoles/chemistry , Interleukin-6/antagonists & inhibitors , Kaempferols/chemistry , Lignans/chemistryABSTRACT
We report herein the design and synthesis of several representative examples of novel mutual prodrugs containing nine distinct types of self-immolative drug-releasable disulfide linkers with urethane, ester, carbonate, or imide linkages between the linker and any two amine/amide/urea (primary or secondary) or carboxyl or hydroxyl (including phenolic)-containing drugs. We also report drug release profiles of a few representative mutual prodrugs in biological fluids such as simulated gastric fluid and human plasma. We also propose plausible mechanisms of drug release from these mutual prodrugs. We have also conducted a few mechanistic studies based on suggested sulfhydryl-assisted cleavage of mutual prodrugs and characterized a few important metabolites to give support to the proposed mechanism of drug release from the reported mutual prodrugs.
Subject(s)
Body Fluids/metabolism , Disulfides/metabolism , Prodrugs/chemistry , Prodrugs/metabolism , Body Fluids/chemistry , Disulfides/chemistry , Drug Design , Humans , Molecular Structure , Prodrugs/chemical synthesisABSTRACT
The antimicrobial efficacy of two phenanthroindolizidine alkaloids, tylophorinidine hydrochloride (TdnH) and tylophorinine hydrochloride (TnnH), isolated from the plant Tylophora indica (local name, Antamul) was evaluated. These were screened for in vitro antifungal and antibacterial activities. Both compounds exhibited potent antifungal activity displaying minimum inhibitory concentrations (MIC) in the range of 2-4 microg/mL for TdnH and 0.6-2.5 microg/mL for TnnH against Candida species.
Subject(s)
Alkaloids/pharmacology , Antifungal Agents/pharmacology , Isoquinolines/pharmacology , Indolizidines , Microbial Sensitivity Tests , Phenanthrenes , Plant Extracts/pharmacology , Tylophora/chemistryABSTRACT
The present study was designed to evaluate, P2026 [(2-((2-(nitrooxy)ethyl)disulfanyl)ethyl 2-(2-(2,6-dichlorophenylamino)phenyl)acetate)], a novel NO (nitric oxide) donor prodrug of diclofenac for its ability to release NO and diclofenac, and whether P2026 provides advantage of improved activity/gastric tolerability over diclofenac. Oral bioavailability of P2026 was estimated from plasma concentration of diclofenac and nitrate/nitrite (NOx). Anti-inflammatory activity was evaluated in three different models of inflammation: acute (carrageenan-induced paw oedema), chronic (adjuvant-induced arthritis), and systemic (lipopolysaccharide-induced endotoxic shock). Gastric tolerability was evaluated from compound's propensity to cause gastric ulcers. P2026 exhibited dose-dependent diclofenac and NOx release. Similar to diclofenac, P2026 showed potent anti-inflammatory activity in acute and chronic model, whereas it improved activity in systemic model. Both diclofenac and P2026 inhibited gastric prostaglandin, but only diclofenac produced dose-dependent haemorrhagic ulcers. Thus, the results suggest that coupling of NO and diclofenac contribute to improved gastric tolerability while retaining the anti-inflammatory properties of diclofenac.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Diclofenac/analogs & derivatives , Inflammation/drug therapy , Nitrates/administration & dosage , Nitrates/pharmacology , Nitric Oxide Donors/pharmacology , Prodrugs/pharmacology , Administration, Oral , Animals , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Anti-Inflammatory Agents, Non-Steroidal/toxicity , Arthritis, Experimental/drug therapy , Biological Availability , Cyclooxygenase Inhibitors/administration & dosage , Cyclooxygenase Inhibitors/pharmacokinetics , Cyclooxygenase Inhibitors/pharmacology , Cyclooxygenase Inhibitors/toxicity , Diclofenac/administration & dosage , Diclofenac/pharmacokinetics , Diclofenac/pharmacology , Diclofenac/toxicity , Dinoprostone/biosynthesis , Drug Evaluation, Preclinical , Epoprostenol/biosynthesis , Gastric Mucosa/metabolism , Male , Nitrates/pharmacokinetics , Nitrates/toxicity , Nitric Oxide/metabolism , Nitric Oxide Donors/administration & dosage , Nitric Oxide Donors/pharmacokinetics , Nitric Oxide Donors/toxicity , Prodrugs/administration & dosage , Prodrugs/pharmacokinetics , Prodrugs/toxicity , Rats , Rats, Sprague-Dawley , Stomach/drug effects , Stomach Ulcer/chemically inducedABSTRACT
Recently, a new class of nitric-oxide-releasing non-steroidal anti-inflammatory drugs (NO-NSAIDs) is being studied as 'Safe NSAIDs' because of their gastric-sparing properties. As an extension of our novel disulfide linker technology, we have designed, synthesized and evaluated novel NO-releasing NSAID prodrugs such as NO-Aspirin (1b-d) and NO-Diclofenac (2b-c). Although the amide-containing derivative 1d did not show any bioavailability, the remaining compounds have shown fair to excellent pharmacokinetic, anti-inflammatory and gastric-sparing properties. Among them, however, the NO-Diclofenac (2b) has shown the most promising pharmacokinetic, anti-inflammatory and NO-releasing properties and protected rats from NSAID-induced gastric damage which could be attributable to the beneficial effects of NO released from these prodrugs.
