SUTAF, a novel β-methoxyacrylate derivative, promotes neurite outgrowth with extracellular signal-regulated kinase and c-jun N-terminal kinase activation

Effects of Carbazole Derivatives on Neurite Outgrowth and Hydrogen Peroxide-Induced Cytotoxicity in Neuro2a Cells

Many studies have demonstrated that oxidative stress plays an important role in several ailments including neurodegenerative diseases and cerebral ischemic injury. Previously we synthesized some carbazole compounds that have anti-oxidant ability in vitro. In this present study, we found that one of these 22 carbazole compounds, compound 13 (3-ethoxy-1-hydroxy-8- methoxy-2-methylcarbazole-5-carbaldehyde), had the ability to protect neuro2a cells from hydrogen peroxide-induced cell death. It is well known that neurite loss is one of the cardinal features of neuronal injury. Our present study revealed that compound 13 had the ability to induce neurite outgrowth through the PI3K/Akt signaling pathway in neuro2a cells. These findings suggest that compound 13 might exert a neurotrophic effect and thus be a useful therapy for the treatment of brain injury.

Minocycline Promotes Neurite Outgrowth of PC12 Cells Exposed to Oxygen-Glucose Deprivation and Reoxygenation Through Regulation of MLCP/MLC Signaling Pathways

Minocycline, a semi-synthetic second-generation derivative of tetracycline, has been reported to exert neuroprotective effects both in animal models and in clinic trials of neurological diseases. In the present study, we first investigated the protective effects of minocycline on oxygen-glucose deprivation and reoxygenation-induced impairment of neurite outgrowth and its potential mechanism in the neuronal cell line, PC12 cells. We found that minocycline significantly increased cell viability, promoted neurite outgrowth and enhanced the expression of growth-associated protein-43 (GAP-43) in PC12 cells exposed to oxygen-glucose deprivation/reoxygenation injury. In addition, immunoblots revealed that minocycline reversed the overexpression of phosphorylated myosin light chain (MLC) and the suppression of activated extracellular signal-regulated kinase 1/2 (ERK1/2) caused by oxygen-glucose deprivation/reoxygenation injury. Moreover, the minocycline-induced neurite outgrowth was significantly blocked by Calyculin A (1 nM), an inhibitor of myosin light chain phosphatase (MLCP), but not by an ERK1/2 inhibitor (U0126; 10 μM). These findings suggested that minocycline activated the MLCP/MLC signaling pathway in PC12 cells after oxygen-glucose deprivation/reoxygenation injury, which resulted in the promotion of neurite outgrowth.

Significance of C-Jun expression in esophageal squamous cell carcinoma

AIM: To investigate the relationship between C-Jun protein expression and clinical biological behavior of esophageal squamous cell carcinoma (ESCC).

METHODS: Immunohistochemistry and RT-PCR were used to detect the expression of C-Jun protein and mRNA in 96 cases of ESCC tissue and matched tumor-adjacent esophageal tissue. The correlation between C-Jun protein expression and clinical biological behavior of ESCC was analyzed.

RESULTS: C-Jun expression in ESCC was significantly higher in ESCC tissue than in matched tumor-adjacent esophageal tissue (0.7703 ± 0.3330 vs 0.2546 ± 0.1328, t = -11.23, P < 0.05). C-Jun protein expression was correlated with lymph node metastasis and TNM stage in ESCC (both P < 0.05).

CONCLUSION: C-Jun protein is highly expressed in ESCC, which correlates with lymph node metastasis and TNM stage. This finding suggests that high expression C-Jun protein may be related to the occurrence and development of ESCC.