OPEN Foundation

L. Wang

Repeated ketamine injections in synergy with antidepressants for treating refractory depression: A case showing 6-month improvement.

Abstract

WHAT IS KNOWN AND OBJECTIVE:
Some patients with refractory depression who fail to respond to rapid injection of standard-dose ketamine are injected with high doses, but the safety and efficacy of this practice are unclear.
CASE DESCRIPTION:
A 57-year-old woman with refractory depression whose symptoms did not improve after 20-seconds intravenous injection of 0.5 mg/kg ketamine went into remission following eight, 1-minute intravenous injections of 1 mg/kg ketamine delivered over a 4-week period. By 6-month follow-up, no significant adverse events had occurred and cognitive function had improved.
WHAT IS NEW AND CONCLUSION:
High-dose intravenous injections of ketamine may stably improve depressive symptoms and cognitive function in patients with refractory depression who do not respond to rapid intravenous injection of standard-dose ketamine. The high-dose treatment appears to be associated with only mild side effects.
Wang, M., Xiong, Z., Su, B., Wang, L., Li, Z., Yang, Y., & Fang, J. (2019). Repeated ketamine injections in synergy with antidepressants for treating refractory depression: A case showing 6-month improvement. Journal of clinical pharmacy and therapeutics., https://doi.org/10.1111/jcpt.13041
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Harmine mediated neuroprotection via evaluation of glutamate transporter 1 in a rat model of global cerebral ischemia.

Abstract

Global cerebral ischemia (GCI) causes energy deficiency results in excessive release of glutamate from neurons. Astrocytic glutamate transporters play a predominant role in keeping extracellular glutamate concentrations below excitotoxic levels. Glutamate transporter 1 (GLT-1) may account for more than 90% of glutamate uptake in adult forebrain. Preclinical findings implicate that Harmine present neuroprotection effects in a rat model of amyotrophic lateral sclerosis disease, and the beneficial effects were specifically due to up-regulation of GLT-1. However, no experiments have explored the potential of Harmine to provide neuroprotection in the setting of GCI. The current study was designed to determine whether Harmine could attenuate cerebral infarction as well as improve neuronal survival after GCI. Furthermore, to test whether the mechanisms were associated with up-regulating of GLT-1, we used a GLT-1 specific inhibitor dihydrokainate (DHK) and analysis the expression of GLT-1 mRNA and protein in cortex of brain. We also examined whether Harmine treatment affected astrocytes activation via immunofluorescence. Our results showed that post-GCI administration of Harmine could attenuate cerebral infarct volume and decrease neurons death. It also caused significantly elevation of GLT-1 mRNA and protein and remarkably attenuation of astrocyte activation. We provide novel clues in understanding the mechanisms of which Harmine exerts its neuroprotective activity in neurological disorders.

Sun, P., Zhang, S., Li, Y., & Wang, L. (2014). Harmine mediated neuroprotection via evaluation of glutamate transporter 1 in a rat model of global cerebral ischemia. Neuroscience letters, 583, 32-36. http://dx.doi.org/10.1016/j.neulet.2014.09.023
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Iboga-Type Alkaloids from Ervatamia officinalis

Abstract

Seven new iboga-type alkaloids, ervaoffines A–D (14), (7S)-3-oxoibogaine hydroxyindolenine (5), ibogaine-5,6-dione (6), and 19-epi-5-oxovoacristine (7), and 10 known alkaloids were isolated from Ervatamia officinalis. The absolute configurations of 17 were determined through X-ray diffraction and electronic circular dichroism (ECD) analyses. Ervaoffines A and B represent the first iboga-type pseudoindoxyl alkaloids in which the C-2 spiro carbon configuration is opposite to that of other members of this class, such as iboluteine (8). The relationship between the absolute configuration of the spiro carbons and the Cotton effect in the ECD spectrum is established for the first time for iboga-type pseudoindoxyl and oxindole alkaloids. Additionally, a plausible biogenetic pathway for these alkaloids is proposed.

Tang, B. Q., Wang, W. J., Huang, X. J., Li, G. Q., Wang, L., Jiang, R. W., … & Ye, W. C. (2014). Iboga-Type Alkaloids from Ervatamia officinalis. Journal of natural products, 77(8), 1839-1846. https://dx.doi.org/10.1021/np500240b
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