Echinacoside ameliorates post-stroke depression by activating BDNF signaling through modulation of Nrf2 acetylation.

BACKGROUND: Post-stroke depression (PSD) affects approximately one-third of stroke survivors, leading to adverse outcomes in rehabilitation, reduced quality of life, and increased mortality rates. Despite these implications, the underlying causes of PSD remain unclear, posing challenges for prevention and treatment. Echinacoside (ECH), a natural compound with known neuroprotective and antidepressant properties, holds significant therapeutic potential for PSD. However, the precise mechanism of its action remains unknown. PURPOSE: To unravel the specific mechanism through which ECH alleviates PSD by exploring the intricate interplay between ECH and Nrf2, as well as its impact on the BDNF/TrkB signaling axis. STUDY DESIGN AND METHODS: A rat PSD model was established though middle cerebral artery occlusion coupled with chronic unpredictable mild stress, followed by ECH treatment. The rats' depressive state was evaluated using the sucrose preference test and force swimming test. Brain damage was assessed through TTC staining, Nissl staining, and TUNEL assay. The multifaceted mechanism of ECH in PSD was investigated using immunofluorescence, immunohistochemistry, RT-qPCR, dual-luciferase assay, and western blotting. Additionally, the interaction between ECH and Nrf2 was explored through molecular docking and microscale thermophoresis. RESULTS: Our findings unveiled a novel facet of ECH action, demonstrating its unique ability to upregulate Nrf2 through acetylation within the hippocampus of PSD-affected rats (p < 0.05). Moreover, ECH showcased its distinctive potential by enhancing BDNF transcriptional activity, activating the BDNF/TrkB signaling axis, and orchestrating a comprehensive response against oxidative stress and apoptosis, thereby alleviating PSD symptoms in rats (p < 0.05). CONCLUSIONS: This study not only provides insights into the pivotal role of Nrf2 in mediating the BDNF/TrkB axis activation by ECH but also highlights the novelty of ECH's mechanism in addressing PSD. The elucidation of these unique aspects positions ECH as a groundbreaking candidate for further exploration and development in the realm of PSD intervention.

Morroniside improves the symptoms of post-stroke depression in mice through the BDNF signaling pathway mediated by MiR-409-3p.

BACKGROUND: Post-stroke depression (PSD) is a common psychiatric symptom after a stroke. Morroniside, an iridoid glycoside found in Cornus officinalis, has garnered significant attention for its potential to alleviate symptoms associated with depression. PURPOSE: This study aims to highlight the potential use of morroniside in the treatment of PSD and elucidate the underlying molecular mechanisms. METHODS: To establish a reliable PSD model, male C57BL/6 mice were subjected to brief MCAO in conjunction with CUMS. Post-morroniside administration, neuronal viability, and hippocampal cell apoptosis were evaluated by Nissl staining and TUNEL detection, respectively. Depression-like behaviors were evaluated using SPT, TST, and FST. The Longa score and cylinder test were used to evaluate the effect of morroniside on motor function. Furthermore, to investigate the underlying molecular mechanisms, bioinformatic analysis and the dual luciferase assay were performed to investigate the MiR-409-3p-BDNF interaction. In addition, subsequent to MiR-409-3p overexpression via AAV virus, we assessed mRNA expression and protein levels of key components within the BDNF/TrkB signaling pathway using RT-qPCR, immunohistochemistry, and western blot analysis. RESULTS: The observed decrease in apoptosis and amelioration of depression-like behaviors strongly indicate the potential of morroniside as a therapeutic agent for PSD. Furthermore, the upregulation of key proteins within the BDNF/TrkB signaling pathway in the cortex suggests that morroniside activates this pathway. Through bioinformatics analysis, MiR-409-3p was identified and found to bind to the BDNF gene, resulting in the inhibition of BDNF expression. Importantly, we demonstrate that morroniside mitigates this inhibitory effect of MiR-409-3p on BDNF, thereby facilitating the activation of the BDNF/TrkB signaling pathway. CONCLUSION: The findings suggest that morroniside demonstrates the ability to improve PSD symptoms through the BDNF/TrkB signaling pathway mediated by MiR-409-3p. These results emphasize the importance of the BDNF signaling pathway in improving PSD symptoms and provide a possible mechanism for morroniside to treat PSD.