H2S Alleviates Neuropathic Pain in Mice by Nrf2 Signaling Pathway Activation.

Neuropathic pain is a chronic pain caused by direct damage to the peripheral or central nervous system, characterized by hyperalgesia, allodynia, and spontaneous pain. Hydrogen sulfide (H2S) therapy has been applied for neuropathic pain treatment, although the underlying mechanisms remain unknown. In this study, we sought to ascertain whether H2S therapy could alleviate neuropathic pain in a model of chronic constriction injury (CCI) and, if so, the potential mechanism. A CCI model was established in mice through a spinal nerve ligation method. Intrathecal injection of NaHS was used to treat CCI model mice. The thermal paw withdrawal latency (TPWL) and mechanical paw withdrawal threshold (MPWT) were used for pain threshold evaluation in mice. A series of experiments including immunofluorescence, enzyme-linked immunosorbent assay, electrophysiological test, mitochondrial DNA (mtDNA) quantification, measurement of ATP content, demethylase activity, and western blot were performed to investigate the specific mechanism of H2S treatment in neuropathic pain. Mice with CCI exposure exhibited a decrease in MPWT and TPWL, an increase in IL-1ß and TNF-α expressions, elevated eEPSP amplitude, an upregulation of mtDNA, and a reduction in ATP production, whereas H2S treatment significantly reversed these changes. Furthermore, CCI exposure induced a remarkable increase in vGlut2- and c-fos-positive as well as vGlut2- and Nrf2-positive cells, an increase in Nrf2 located in the nucleus, and an upregulation of H3K4 methylation, and H2S treatment further enhanced these changes. In addition, ML385, a selective Nrf2 inhibitor, reversed the neuroprotective effects of H2S. H2S treatment mitigates CCI-induced neuropathic pain in mice. This protective mechanism is possibly linked to the activation of the Nrf2 signaling pathway in vGlut2-positive cells.

Expression of VGLL4 and YAP protein in gastric carcinoma tissues and tumor prognosis.

BACKGROUND: The purpose of this study was to investigate the relationship between expression of VGLL4 and YAP protein in gastric carcinoma and adjacent normal tissues and its relationship with clinicopathological parameters and its significance in prognosis of gastric cancer. METHODS: The expression of VGLL4 and YAP protein in gastric carcinoma tissues and adjacent tissues were detected by fluorescence quantitative PCR, Western blot and immunohistochemistry. The relationship between the expression of VGLL4 and YAP protein and the clinicopathological parameters of gastric cancer patients was analyzed to determine its impact on the invasion and metastasis and prognosis of patients. RESULTS: The expression of VGLL4 protein in gastric carcinoma was lower than that in adjacent tissues, and it was negatively correlated with infiltration depth, lymph node metastasis and TNM staging; the expression of YAP protein in gastric carcinoma was higher than that in adjacent tissues, and it was positively correlated with age, tumor differentiation, depth of invasion, lymph node metastasis and TNM staging. CONCLUSIONS: VGLL4 protein decreased in gastric cancer tissue and was negatively correlated with tumor progression and malignancy degree, suggesting that it is a potential antitumor protein; YAP protein increased in gastric cancer and is a proto-oncogene.