Sigma 1 receptor agonist cutamesine promotes plasticity of serotonergic boutons in lumbar enlargement in spinal cord injured rats

Hypidone Hydrochloride (YL-0919), a Sigma-1 Receptor Agonist, Improves Attention by Increasing BDNF in mPFC

Background/Objectives: The available treatment for attention deficit is drug therapy, but the drugs show poor adverse effect profiles and individual variability in response, especially in adults. Hypidone hydrochloride (YL-0919) is a selective sigma-1 receptor agonist that demonstrated a faster onset antidepressant effect in our previous studies. Current studies aim to study the attention-enhancing effect and mechanism of YL-0919. Methods: We used the five-choice serial reaction time task (5-CSRTT) to measure the attention-improving effect of YL-0919 in SD rats under a physiological state and exogenous corticosterone (CORT)-exposed state. The depression/anxiety-like behavioral experiments were used in the CORT-exposed rats. Immunofluorescence staining, western blotting, and Golgi-Cox staining were used to investigate the attention-improving mechanism of YL-0919. Results: The studies found that intragastric administration of 2.5 and 5 mg/kg YL-0919 for 6 days significantly improved the attention of SD rats under a physiological state. CORT exposure caused depression/anxiety-like behaviors and attention deficit in the rats. Intragastric administration of 3 mg/kg SA4503 or 2.5 and 5 mg/kg YL-0919 for 6 days significantly alleviated attention deficit in SD rats under an exogenous CORT-exposed state. In addition, YL-0919 administration obviously increased the expression of BDNF, PSD95, and synapsin1 and improved the dendritic complexity and the dendritic spine density in the medial prefrontal cortex (mPFC). Conclusions: These results reveal that YL-0919 as a selective sigma-1 receptor agonist can significantly improve the attention of SD rats under a physiological state and exogenous CORT-exposed state. Improving the level of BDNF and dendritic complexity in the mPFC may be the important mechanisms of YL-0919 to improve attention. The study also provides a potential novel target for the drug therapy of attention deficit.

Promising Advances in Pharmacotherapy for Patients with Spinal Cord Injury-A Review of Studies Performed In Vivo with Modern Drugs

Spinal cord injury (SCI) is a pathological neurological condition that leads to significant motor dysfunction. It is a condition that occurs as a result of tragic accidents, violent acts, or as a consequence of chronic diseases or degenerative changes. The current treatments for patients with SCI have moderate efficacy. They improve the quality of life of patients, but they are still doomed to long-term disability. In response to the modern directions of research on possible therapeutic methods that allow for the recovery of patients with SCI, a scientific review publication is needed to summarize the recent developments in this topic. The following review is focused on the available pharmacological treatments for SCIs and the problems that patients face depending on the location of the injury. In the following review, the research team describes problems related to spasticity and neuropathic pain; possible therapeutic pathways are also described for neuroprotection and the improvement of neurotransmission within the injured spinal cord, and the review focuses on issues related to oxidative stress.

Discovery of 3-(2-aminoethyl)-thiazolidine-2,4-diones as a novel chemotype of sigma-1 receptor ligands

Sigma receptor is a transmembrane non-GPCR protein expressed mainly in the endoplasmic reticulum membrane associated with mitochondria. It is classified into two types: Sigma-1 (S1R) and Sigma-2 (S2R) based on their biological functions. S1R has been implicated in many neurological disorders such as anxiety, schizophrenia, and depression. Therefore, S1R ligands possess a variety of potential clinical applications with a great interest in the treatment of neuropathic pain. In this study, we report the discovery of a novel lead compound for S1R binding, based on the thiazolidine-2,4-dione nucleus. We have explored hydrophobic groups of different sizes on both sides of the five-membered ring scaffold guided by the crystal structure of S1R. Six compounds showed more than 50% displacement of the radioligand at 10 µM concentration with compound 6c resulting in 100% displacement and a Ki of 95.5 nM. Moreover, compounds 6c and 6e showed a significant selectivity over S2R. In addition, molecular docking predicted that all the compounds showed the critical salt bridge with Glu172 with variable degrees of π-stacking interaction with Tyr103. Upon optimization, this series of compounds could represent potential clinically useful S1R ligands for pain management.

The ROCK inhibitor Y-27632 ameliorates blood-spinal cord barrier disruption by reducing tight junction protein degradation via the MYPT1-MLC2 pathway after spinal cord injury in rats

The blood-spinal cord barrier (BSCB) is a physiological barrier between the blood and spinal cord parenchyma. This study aims to determine whether Y-27632, a Rho-associated protein kinase (ROCK) inhibitor, can protect the BSCB using in vivo models. The Evans blue fluorescence assay was used to detect leakage of the BSCB. Western blotting was used to define alterations in ROCK-related and tight junction (TJ) protein expression. Immunofluorescence triple-staining was used to evaluate histologic alterations in TJs. Locomotor function was evaluated using the open-field test, the Basso-Beattie-Bresnahan score, and footprint analysis. Two peaks of BSCB leakage after spinal cord injury (SCI) occurred at 24 h and 5 days. The ROCK inhibitor reduced the BSCB leakage at the second peak after SCI. Moreover, the ROCK inhibitor ameliorated the integrity of the BSCB and improved motor function recovery after SCI by regulating the phosphorylation of myosin phosphatase subunit-1 (MYPT1) and cofilin. ROCK inhibitors might protect the BSCB, which provides a new strategy for transitioning SCI treatment from the bench to bedside.