thiosemicarbazide and Disease-Models--Animal

The decoction from the stem bark of Psychotria camptopus (Rubiaceae) is used in the Cameroonian pharmacopoeia to treat neurological pathologies including epilepsy.. The present work was undertaken to study the anticonvulsant properties of the aqueous (AE) and methanol (ME) extracts from the stem bark of P. camptopus in acute models of epileptic seizures in Wistar rats.. AE and ME were obtained by decoction and maceration of the stem bark powder in water and methanol, respectively. They were tested orally at the doses of 40, 80 and 120 mg/kg, on the latency of onset and duration of epileptic seizures induced by pentylene tetrazole (PTZ, 70 mg/kg, i.p.). The kinetic effect of both extracts at 120 mg/kg was evaluated. Their effects on diazepam (50 mg/kg) induced sleep and strychnine (STR, 2.5 mg/kg, i.p.) induced seizures were determined. ME was further tested on picrotoxin (PIC, 7.5 mg/kg, i.p.) and thiosemicarbazide (TSC, 50 mg/kg, i.p.) induced seizure models. The phytochemical composition of ME was assessed using LC-MS method, as well as its acute toxicity.. AE and ME significantly (p < 0.001) reduced the duration of seizures in both PTZ and STR models. Their maximal effect was observed at 1 h after administration, though their effect at 120 mg/kg was maintained (p < 0.05) up to 24 h post-treatment. Both extracts significantly (p < 0.01) reduced sleep duration. ME significantly (p < 0.001) increased the latency of rat death on PIC-induced convulsions. In TSC rats, ME significantly (p < 0.001) delayed the latency to the first convulsion, and decreased the duration and frequency of convulsions. ME showed no acute toxicity while its phytochemical screening revealed the presence of two flavonoids (Rutin and Butin), two triterpenoid saponins (Psycotrianoside B and Bauerenone) and four alkaloids (10-Hydroxy-antirhine, 10-hydroxy-iso-deppeaninol, Emetine and Hodkinsine). In conclusion, AE and ME from the stem bark of P. camptopus have comparable anticonvulsant properties. The effect of ME is likely due to the presence of flavonoids and alkaloid and the activation of GABA pathway. These results further justify and support the use of P. camptopus in traditional medicine for the treatment of epilepsy.

Topics: Animals; Anticonvulsants; Behavior, Animal; Diazepam; Disease Models, Animal; Epilepsy; Methanol; Mice; Pentylenetetrazole; Phytochemicals; Picrotoxin; Plant Bark; Plant Extracts; Plant Stems; Psychotria; Rats, Wistar; Seizures; Semicarbazides; Sleep; Sleep Latency; Strychnine; Water

We, herein, describe the synthesis of a series of novel aryl tethered 7,8-dihydroquinolin-5(6H)-ylidenehydrazinecarbothioamides 4a-v, which showed in vitro and in vivo antimycobacterial activity against Mycobacterium tuberculosis (Mtb) H37Rv. The intermediates dihydro-6H-quinolin-5-ones 3a-v were synthesized from β-enaminones, reacting with cyclochexane-1,3-dione/5,5-dimethylcyclohexane-1,3-dione and ammonium acetate using a modified Bohlmann-Rahtz reaction conditions. They were further reacted with thiosemicarbazide to give the respective hydrazine carbothioamides 4a-v. All the new analogues 4a-v, were characterized by their NMR and mass spectral data analysis. Among the twenty-two compounds screened for in vitro antimycobacterial activity against Mycobacterium tuberculosis H37Rv (ATCC27294), two compounds, 4e and 4j, exhibited the highest inhibition with an MIC of 0.39 µg/mL. Compounds 4a, 4g, and 4k were found to inhibit Mtb at an MIC of 0.78 µg/mL. Hydrazinecarbothioamides 4a-k, exhibited enhanced activity than dihydroquinolinones 3a-k. The observed increase in potency provides a clear evidence that hydrazinecarbothioamide is a potential pharmacophore, collectively imparting synergistic effect in enhancing antitubercular activity of the dihydroquinolinone core. The in vivo (Zebra fish) antimycobacterial screening of the in vitro active molecules led to the identification of a hit compound, 4j, with significant activity in the Mtb nutrient starvation model (2.2-fold reduction). Docking studies of 4j showed a hydrogen bond with the P156 residue of the protein.

Topics: Animals; Antitubercular Agents; Disease Models, Animal; Drug Design; Humans; Hydrazines; Microbial Sensitivity Tests; Molecular Docking Simulation; Mycobacterium tuberculosis; Quinolones; Structure-Activity Relationship; Thioamides; Tuberculosis; Zebrafish

Hypoxia-induced immediate expression of transcription factor HIF-1α in the brain cortex is regulated by succinate produced in both the tricarbonic acid cycle and GABA shunt reactions and is induced by succinate-containing drugs. These facts prove the existence of succinate-dependent signalling regulation involved in immediate and delayed molecular adaptation and increased body resistance to oxygen deficiency, where succinate acts as a signal molecule. The intensity of this process differs in animals with low and high resistance to hypoxia.

Topics: Adaptation, Physiological; Altitude Sickness; Animals; Cerebral Cortex; Citric Acid Cycle; Disease Models, Animal; Electron Transport Complex I; Electron Transport Complex II; gamma-Aminobutyric Acid; Gene Expression Regulation; Hypoxia-Inducible Factor 1, alpha Subunit; Male; Phenobarbital; Picolines; Rats; Rats, Inbred Strains; Semicarbazides; Signal Transduction; Succinate Dehydrogenase; Succinic Acid

Earlier, we have identified a number of piperazine derivatives having good anticonvulsant activity in vivo and as a part of our ongoing search for potent anticonvulsant agent, we herein describes the synthesis of an aryl piperazine derivative "1-[4-(4-benzo[1,3]dioxol-5-ylmethyl-piperazin-1-yl)-phenyl]-3-phenyl-urea" (BPPU). The anticonvulsant and antidepressant activity of BPPU was checked in various in vivo models.. Anticonvulsant activity was assessed in maximal electroshock test (MES) and subcutaneous pentylenetetrazole (scPTZ) induced seizure tests. Moreover, plausible mechanistic studies were also performed by using several chemical induced seizure models. The antidepressant activity of BPPU was checked in forced swim test (FST) and tail suspension test (TST) in mice. Drug safety profile was studied in sub-acute toxicity rat model at a dose of 100mg/kg, per oral for 14 days.. BPPU exhibited excellent protection against seizures induced by MES and scPTZ in mice as well as rats. In pilocarpine induced model of status epilepticus (SE), BPPU demonstrated 50% protection at a dose of 100mg/kg in rats. BPPU also successfully inhibited seizures induced by 3-mercaptopropionic acid (3-MPA) and thiosemicarbazide (TSC) in mice thus, suggested that BPPU might influence GABA-ergic neurotransmission in the brain. Moreover, BPPU showed good antidepressant activity and did not exhibit any significant toxicity.. BPPU displayed broad spectrum of anticonvulsant activity in several seizure models along with satisfactory antidepressant activity. Therefore, BPPU may be further developed as a potential therapeutic agent for therapy of epileptic disorders.

Topics: 3-Mercaptopropionic Acid; Animals; Anticonvulsants; Antidepressive Agents; Disease Models, Animal; Electroshock; Mice; Pentylenetetrazole; Phenylurea Compounds; Piperazine; Piperazines; Rats; Rats, Wistar; Seizures; Semicarbazides; Status Epilepticus

Glutamic acid decarboxylase (GAD), the enzyme responsible for GABA synthesis, requires pyridoxal phosphate (PLP) as a cofactor. Thiosemicarbazide (TSC) and γ-glutamyl-hydrazone (PLPGH) inhibit the free PLP-dependent isoform (GAD65) activity after systemic administration, leading to epilepsy in mice and in young, but not in adult rats. However, the competitive GAD inhibitor 3-mercaptopropionic acid (MPA) induces convulsions in both immature and adult rats. In the present study we tested comparatively the epileptogenic and neurotoxic effects of PLPGH, TSC and MPA, administered by microdialysis in the hippocampus of adult awake rats. Cortical EEG and motor behavior were analyzed during the next 2h, and aspartate, glutamate and GABA were measured by HPLC in the microdialysis-collected fractions. Twenty-four hours after drug administration rats were fixed for histological analysis of the hippocampus. PLPGH or TSC did not affect the motor behavior, EEG or cellular morphology, although the extracellular concentration of GABA was decreased. In contrast, MPA produced intense wet-dog shakes, EEG epileptiform discharges, a >75% reduction of extracellular GABA levels and remarkable neurodegeneration of the CA1 region, with >80% neuronal loss. The systemic administration of the NMDA glutamate receptor antagonist MK-801 30 min before MPA did not prevent the MPA-induced epilepsy but significantly protected against its neurotoxic effect, reducing neuronal loss to <30%. We conclude that in adult awake rats, drugs acting on PLP availability have only a weak effect on GABA neurotransmission, whereas direct GAD inhibition produced by MPA induces hyperexcitation leading to epilepsy and hippocampal neurodegeneration. Because this degeneration was prevented by the blockade of NMDA receptors, we conclude that it is due to glutamate-mediated excitotoxicity consequent to disinhibition of the hippocampal excitatory circuits.

Topics: Amino Acids; Animals; Disease Models, Animal; Dizocilpine Maleate; Dose-Response Relationship, Drug; Enzyme Inhibitors; Epilepsy; Hippocampus; Male; Microdialysis; Neurodegenerative Diseases; Neuroprotective Agents; Phenylacetates; Pyridoxal Phosphate; Rats; Rats, Wistar; Semicarbazides; Time Factors; Wakefulness

The objective of this study was to investigate the anti-inflammatory and antioxidant activity of new thiazolyl-carbonyl-thiosemicarbazides and thiazolyl-azole derivatives as potential iNOS inhibitors. The in vivo anti-inflammatory effects of the new thiazole compounds were studied in a turpentine oil induced inflammation model. Their anti-inflammatory activity was assessed by evaluating the acute phase bone marrow response, phagocytes' activity, NO synthesis and antioxidant capacity. The new thiazole compounds have anti-inflammatory effects by lowering bone marrow acute phase response and oxidative stress. The best anti-inflammatory and antioxidant effect was found for thiazolyl-carbonyl-thiosemicarbazides Th-1-8, thiazolyl-1,3,4-oxadiazole Th-20 and thiazolyl-1,3,4-thiadiazole Th-21. Virtual screening of thiazole derivatives against the oxygenase domain of chain A from 2Y37 revealed that all twenty-two compounds bind the active site of inducible nitric oxide synthase (iNOS). Based on the virtual screening and on the results obtained above, the activity may be due to their capacity to reduce the NO synthesis by blocking the bind of L-Arg in the active site of iNOS, the compounds binding the synthase by hydrogen bonds between the NH (2 and/or 4) of thiosemicarbazide fragment (Th-2-8) or N2/N3 from azole cycles and by the thiol function (Th-9-22).

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Azoles; Disease Models, Animal; Enzyme Inhibitors; Hydrogen Bonding; Inflammation; Male; Nitric Oxide; Nitric Oxide Synthase Type II; Oxidative Stress; Rats; Rats, Wistar; Semicarbazides

The experiments on focal penicillin-induced epileptic activity in the brain cortex (Wistar rats) and bicuculline- and thiosemicarbazide-induced seizures (Icr:Icl mice) showed that the glutapyrone possessed a significant antiepileptic activity. As previously shown, that glutapyrone has an influence on 45Ca2+ uptake by rat cortical synaptosomes (evoked by K+ depolarization) as compared with nifedipine and nimodipine, and it was effective in pentylenetetrazol-induced seizures in rats and mice. The mechanism of action of convulsants is associated with the disturbance of different links of GABAergic inhibition. It is suggested that the antiepileptic effects of glutapyrone are realized at least in part by the participation of GABAergic system.

Topics: Animals; Anticonvulsants; Bicuculline; Convulsants; Dihydropyridines; Disease Models, Animal; Drug Evaluation, Preclinical; Epilepsies, Partial; Glutamates; Male; Mice; Mice, Inbred ICR; Penicillins; Rats; Rats, Wistar; Seizures; Semicarbazides