trans-sodium-crocetinate and Brain-Infarction

Trans sodium crocetinate (TSC) is a synthetic small-molecule antioxidant that has the ability to enhance oxygen diffusion to hypoxic tissue. Because TSC is a promising drug candidate to treat acute ischemic stroke (AIS), we tested the hypothesis that TSC may be neuroprotective following cerebral ischemia using a rabbit small clot embolic stroke model (RSCEM) using clinical rating scores as the endpoint. TSC or saline was administered IV following the injection of small blood clots into the brain vasculature. Behavior was measured 24 h following embolization in order to calculate the effective stroke dose (P(50)) that produces neurological deficits in 50% of the rabbits. A treatment is considered beneficial if it significantly increases the P(50) compared to control. TSC (0.25 mg/kg) given 5 or 60 min following embolization significantly (p<0.05) increased P(50) values by 104% and 181%; but not when given 3 h post-embolization (48% increase, p>0.05). tPA (3.3 mg/kg) produced a significant increase in P(50) when given 1, but not 3 h following embolization. In combination studies, when TSC was administered 1 h and tPA was given either 1 or 3 h following embolization, the group P(50) values were increased by 291% and 140%, respectively. In addition, TSC plus tPA administered 3 h following embolization significantly (p<0.05) increased the group P(50) value by 90%. There were no significant effects (p>0.05) of either TSC alone or TSC administered in combination with tPA on intracerebral hemorrhage incidence. This study suggests that TSC may be used for the treatment of AIS either alone or when administered before or concomitant with tPA to improve clinical rating scores with a therapeutic window for TSC therapy up to 3 h in rabbits. Moreover, it appears that TSC can be administered with tPA, since the combination did not result in any significant change in intracerebral hemorrhage incidence.

Topics: Animals; Brain Infarction; Brain Ischemia; Carotenoids; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Synergism; Drug Therapy, Combination; Drug-Related Side Effects and Adverse Reactions; Emergency Medical Services; Fibrinolytic Agents; Intracranial Embolism; Male; Neuroprotective Agents; Rabbits; Time Factors; Tissue Plasminogen Activator; Treatment Outcome; Vitamin A

Crocus sativus L. (saffron) has been used as a spice for flavoring and coloring food preparations, and in Chinese traditional medicine as an anodyne or tranquilizer. Our previous study demonstrated that crocin, a carotenoid pigment of saffron, can suppress the serum deprivation-induced death of PC12 cells by increasing glutathione (GSH) synthesis and thus inhibiting neutral sphingomyelinase (nSMase) activity and ceramide formation. The carotenoid pigments of saffron consist of crocetin di-(beta-d-glucosyl)-ester [dicrocin], crocetin-(beta-d-gentiobiosyl)-(beta-d-glucosyl)-ester [tricrocin] and crocetin-di-(beta-d-gentiobiosyl)-ester [crocin]. Saffron also contains picrocrocin, the substance causing saffron's bitter taste. In this study, to confirm whether neuroprotective effects of saffron are caused solely by crocin, we examined the antioxidant and GSH-synthetic activities of these crocins in PC12 cells under serum-free and hypoxic conditions. Measurements of cell viability, peroxidized membrane lipids and caspase-3 activity showed that the rank order of the neuroprotective potency at a concentration of 10 muM was crocin>tricrocin>dicrocin and picrocrocin (the latter two crocins had a little or no potency). In addition, we show that among these saffron's constituents, crocin most effectively promotes mRNA expression of gamma-glutamylcysteinyl synthase (gamma-GCS), which contributes to GSH synthesis as the rate-limiting enzyme, and that the carotenoid can significantly reduce infarcted areas caused by occlusion of the middle cerebral artery (MCA) in mice.

Topics: Animals; Antioxidants; Brain Infarction; Carotenoids; Caspase 3; Cell Hypoxia; Cell Survival; Crocus; Cyclohexenes; Disease Models, Animal; Glucosides; Glutamate-Cysteine Ligase; Glutathione; Infarction, Middle Cerebral Artery; Lipid Peroxidation; Male; Membrane Lipids; Mice; Molecular Structure; Neurons; Neuroprotective Agents; PC12 Cells; Rats; Structure-Activity Relationship; Terpenes; Time Factors; Vitamin A