morphinans and Hypoxia

BACKGROUND In the present study, we aimed to investigate the effects of sinomenine (SIN) on chronic intermittent hypoxia (CIH)- induced lung injury in rats, and to explore the underlying mechanisms. MATERIAL AND METHODS To perform the investigation, a CIH rat model was established. ELISA assay was applied to detect the level of inflammatory cytokines. Oxidative stress bio-markers (MDA, SOD, and CAT) were determined in lung tissues. In addition, the expression level of NADPH oxidase 2 (Nox2) was analyzed by Western blotting and qRT-PCR, respectively. RESULTS The results showed that compared with other groups, more obvious pulmonary pathological changes were observed in the CIH group. The level of inflammatory cytokines in the CIH group was markedly higher than that in the control and Con-S groups. Compared with the control and Con-S groups, oxidative stress was notably increased in the CIH group. Expression of Nox2 was also increased in the CIH group. The effects caused by CIH in rats were attenuated by SIN treatment. CONCLUSIONS SIN can reverse chronic intermittent hypoxia-induced lung injury through inhibiting inflammation and oxidative stress.

Topics: Animals; Chronic Disease; Cytokines; Down-Regulation; Hypoxia; Inflammation; Inflammation Mediators; Lung; Lung Injury; Male; Mice; Morphinans; NADPH Oxidases; NF-E2-Related Factor 2; Oxidative Stress; Rats, Sprague-Dawley; Signal Transduction

Astrocyte-mediated neuroinflammation plays a critical role in ischemic stroke-induced secondary cerebral injury. Previous studies have suggested that the dopamine D2 receptor (DRD2) acts as a key target in regulating the neuroinflammatory response. However, the underlying molecular mechanisms are still unknown, and effective DRD2 agonists are lacking. In the present study, we examined the anti-inflammatory and neuroprotective effects of sinomenine (Sino), a monomeric compound with potential immunoregulatory properties in nervous system.. TTC staining, apoptosis assay, evaluation of brain edema, and neurological assessment were performed in the middle cerebral artery occlusion (MCAO) mouse model. Primary astrocytes exposed to oxygen glucose deprivation (OGD) were used in the in vitro experiments. Quantitative PCR was applied to assess the levels of inflammatory cytokines. Multi-labeling immunofluorescence, Western blot, co-immunoprecipitation, and electrophoretic mobility shift assay (EMSA) were also used to investigate the molecular mechanisms underlying the Sino-mediated anti-inflammatory effects in vivo and in vitro.. Sino remarkably attenuated the cerebral infarction and neuronal apoptosis, reduced the levels of inflammatory cytokines, and alleviated neurological deficiency in MCAO mice. Sino significantly inhibited astrocytic activation and STAT3 phosphorylation as well as increased DRD2 and αB-crystallin (CRYAB) expression after MCAO. In vitro, Sino blocked OGD-induced activation of STAT3 and generation of pro-inflammatory cytokines in primary astrocytes, and these effects were significantly abolished by either DRD2 or CRYAB knockdown. Additionally, Sino induced up-regulation and nuclear translocation of CRYAB in astrocytes and enhanced the interaction between CRYAB and STAT3, which further inhibited the activation and DNA-binding activity of STAT3.. Our study demonstrates that Sino activates astrocytic DRD2 and thereby suppresses neuroinflammation via the CRYAB/STAT3 pathway, which sheds some light on a promising therapeutic strategy for ischemic stroke.

Topics: alpha-Crystallin B Chain; Animals; Animals, Newborn; Antirheumatic Agents; Astrocytes; Brain Edema; Cells, Cultured; Cerebral Infarction; Disease Models, Animal; Encephalitis; Hypoxia; Infarction, Middle Cerebral Artery; Mice; Mice, Inbred C57BL; Morphinans; Nervous System Diseases; Receptors, Dopamine D2; RNA Interference; Signal Transduction; STAT3 Transcription Factor

Herein we report the development and biological screening of a bioorthogonal palladium-labile prodrug of the nucleoside analogue floxuridine, a potent antineoplastic drug used in the clinic to treat advanced cancers. N-propargylation of the N3 position of its uracil ring resulted in a vast reduction of its biological activity (~6,250-fold). Cytotoxic properties were bioorthogonally rescued in cancer cell culture by heterogeneous palladium chemistry both in normoxia and hypoxia. Within the same environment, the reported chemo-reversible prodrug exhibited up to 1,450-fold difference of cytotoxicity whether it was in the absence or presence of the extracellular palladium source, underlining the precise modulation of bioactivity enabled by this bioorthogonally-activated prodrug strategy.

Topics: Antineoplastic Agents; Cell Line, Tumor; Dealkylation; Drug Screening Assays, Antitumor; Floxuridine; Humans; Hypoxia; Morphinans; Oxygen; Palladium; Prodrugs

The cardiac electrophysiological effects of 16-methylcyprenorphine (M8008), nor-binaltorphimine (NBT) and naltrexone, which are relatively specific opioid antagonists for delta, kappa and mu receptors, respectively, were studied in paced (1.5 Hz) sheep Purkinje fibres in vitro. M8008 (1 ng ml-1-10 micrograms ml-1) caused a concentration-dependent reduction in the maximum rate of depolarisation of phase 0 (MRD) and in the action potential duration measured at 50% repolarisation, APD50. Neither NBT (10 ng ml-1-10 micrograms ml-1) nor naltrexone (1 ng ml-1-10 micrograms ml-1) produced any significant effect on the cardiac action potential. In the presence of a physiological salt solution modified to mimic some of the changes that occur during myocardial ischaemia (i.e. hypoxia, acidosis, hyperkalaemia), M8008 caused a more marked reduction in MRD and prolonged rather than shortened APD50. These results suggest that the reported antiarrhythmic activity of M8008, but not NBT or naltrexone, may be, at least in part, explained by a direct cardiac electrophysiological action.

Topics: Acidosis; Action Potentials; Animals; Coronary Disease; Hyperkalemia; Hypoxia; Morphinans; Naltrexone; Narcotic Antagonists; Purkinje Fibers; Sheep

The dextrorotatory opioid derivatives, dextrorphan and dextromethorphan, can attenuate hypoxic injury in cortical cell cultures. This effect is concentration-dependent in the micromolar range, and not strongly stereospecific, as it can also be demonstrated with the levorotatory enantiomer of dextrorphan, levorphanol. The possibility that these clinically available compounds may have therapeutic utility in hypoxic or ischemic encephalopathy warrants further investigation.

Topics: Animals; Brain Ischemia; Cells, Cultured; Cerebral Cortex; Dextromethorphan; Dextrorphan; Hypoxia; Levorphanol; Mice; Morphinans; Neurons

In an isolated perfused cat lung preparation and a perfused lobe of dog lung preparation a pressor response of the pulmonary circulation was elicited to alveolar hypoxia (5% oxygen). The magnitude of this reponse was not affected by either of the opioid drugs, morphine or buprenorphine.

Topics: Animals; Buprenorphine; Cats; Dogs; Hypoxia; In Vitro Techniques; Lung; Morphinans; Morphine; Perfusion; Pulmonary Circulation; Vasoconstriction

Topics: Anesthesia; Anesthetics; Barbiturates; Blood Volume; Diazepam; Female; Fetal Diseases; Gestational Age; Heart Rate; Humans; Hypotension; Hypoxia; Maternal-Fetal Exchange; Morphinans; Muscle Relaxants, Central; Pregnancy; Pregnancy Complications; Respiration; Vascular Resistance

Topics: Antidepressive Agents; Barbiturates; Blood Circulation; Carbamates; Carbon Monoxide Poisoning; France; Humans; Hypoxia; Lung Diseases; Morphinans; Phenothiazines; Poisoning; Respiration; Salicylates; Seizures; Trichloroethylene; Vascular Diseases