The involvement of soluble epoxide hydrolase in the development of cardiovascular diseases through epoxyeicosatrienoic acids.

Arachidonic acid (AA) has three main metabolic pathways: the cycloxygenases (COXs) pathway, the lipoxygenases (LOXs) pathway, and the cytochrome P450s (CYPs) pathway. AA produces epoxyeicosatrienoic acids (EETs) through the CYPs pathway. EETs are very unstable in vivo and can be degraded in seconds to minutes. EETs have multiple degradation pathways, but are mainly degraded in the presence of soluble epoxide hydrolase (sEH). sEH is an enzyme of bifunctional nature, and current research focuses on the activity of its C-terminal epoxide hydrolase (sEH-H), which hydrolyzes the EETs to the corresponding inactive or low activity diol. Previous studies have reported that EETs have cardiovascular protective effects, and the activity of sEH-H plays a role by degrading EETs and inhibiting their protective effects. The activity of sEH-H plays a different role in different cells, such as inhibiting endothelial cell proliferation and migration, but promoting vascular smooth muscle cell proliferation and migration. Therefore, it is of interest whether the activity of sEH-H is involved in the initiation and progression of cardiovascular diseases by affecting the function of different cells through EETs.

Chronic Pain-Related Cognitive Deficits: Preclinical Insights into Molecular, Cellular, and Circuit Mechanisms.

Cognitive impairment is a common comorbidity of chronic pain, significantly disrupting patients' quality of life. Despite this comorbidity being clinically recognized, the underlying neuropathological mechanisms remain unclear. Recent preclinical studies have focused on the fundamental mechanisms underlying the coexistence of chronic pain and cognitive decline. Pain chronification is accompanied by structural and functional changes in the neural substrate of cognition. Based on the developments in electrophysiology and optogenetics/chemogenetics, we summarized the relevant neural circuits involved in pain-induced cognitive impairment, as well as changes in connectivity and function in brain regions. We then present the cellular and molecular alternations related to pain-induced cognitive impairment in preclinical studies, mainly including modifications in neuronal excitability and structure, synaptic plasticity, glial cells and cytokines, neurotransmitters and other neurochemicals, and the gut-brain axis. Finally, we also discussed the potential treatment strategies and future research directions.

Activation of LXRs alleviates neuropathic pain-induced cognitive dysfunction by modulation of microglia polarization and synaptic plasticity via PI3K/AKT pathway.

OBJECTIVE: Cognitive dysfunction is a common comorbidity in patients with chronic pain. Activation of Liver X receptors (LXRs) plays a potential role in improving cognitive disorders in central nervous diseases. In this study, we investigated the role of LXRs in cognitive deficits induced by neuropathic pain. METHODS: We established the spared nerve injury (SNI) model to investigate pain-induced memory dysfunction. Pharmacological activation of LXRs with T0901317 or inhibition with GSK2033 was applied. PI3K inhibitor LY294002 was administered to explore the underlying mechanism of LXRs. Changes in neuroinflammation, microglia polarization, and synaptic plasticity were assessed using biochemical technologies. RESULTS: We found that SNI-induced cognitive impairment was associated with reduced LXRß expression, increased M1-phenotype microglia, decreased synaptic proteins, and inhibition of PI3K/AKT signaling pathway in the hippocampus. Activation of LXRs using T0901317 effectively alleviated SNI-induced cognitive impairment. Additionally, T0901317 promoted the polarization of microglia from M1 to M2, reduced pro-inflammatory cytokines, and upregulated synaptic proteins in the hippocampus. However, administration of GSK2033 or LY294002 abolished these protective effects of T0901317 in SNI mice. CONCLUSIONS: LXRs activation alleviates neuropathic pain-induced cognitive impairment by modulating microglia polarization, neuroinflammation, and synaptic plasticity, at least partly via activation of PI3K/AKT signaling in the hippocampus. LXRs may be promising targets for addressing pain-related cognitive deficits.

A randomized controlled trial examining a Tranquil sitting intervention compatible with Confucian values.

Introduction: During the COVID-19 pandemic in China, the silent management (Lockdown) policy has caused severe sleep problems for university students. Long-term isolation may further deteriorate sleep quality, and it requires practical interventions. Today in mental and sleep health, interventions based on Buddhist, Taoist and Confucian ethics have been proven effective in reducing cognition and sleep disorders. However, such interventions also have limitations. They tend to focus on peace of mind or some technical means with the main direction of symptom improvement but neglect the mundane activities of daily life. Methods: We conducted an innovative tranquil sitting intervention program based on the Chinese Confucian value of the "tranquility and reverence" method, integrating various intervention techniques traditionally recognized as effective for achieving more lasting mental health and sleep quality. This study aims to assess the effectiveness and feasibility of a tranquil sitting intervention in improving sleep problems in isolated university students. Using a randomized control trial (RCT), the participants in the intervention program (n = 35) practiced the tranquil sitting intervention program for ten weeks. They had their PSQI scores measured at the pre-experimental, post-test, and 1-month follow-up time points and compared to the control group (n = 35). Results: The participants who received the tranquil sitting intervention had significantly better sleep quality than the control group, with moderate to large effect sizes in the middle and late stages. The instructor may challenge the intervention group at the beginning of the tranquil sitting technique. However, the improvement in sleep quality was significant after fully mastering the method. Discussion: The intervention program in this study emphasized the importance of "tranquility" and showed the same sleep improvement as in other traditional interventions. In conclusion, this intervention is a feasible and promising new approach to improving sleep quality among youths.

Rapid injection of lumbar dorsal root ganglia under direct vision: Relevant anatomy, protocol, and behaviors.

Introduction: Dorsal root ganglia (DRG) are anatomically well-defined structures that contain all primary sensory neurons and are distension nodules of the dorsal root in the spinal cord near the medial surface of each foramen. Therefore, DRG is considered to be a desirable target for injection to manage chronic pain. But it presents a limitation in probing deep into it without in vivo injection technology. Methods: Here, we described a technique for administering intraganglionic injections of lumbar DRG under direct vision. We use partial osteotomy rather than laminectomy, which removes more bone, to preserve spinal structures while gaining adequate DRG access. To monitor the intraoperative progress of the DRG injection, a non-toxic dye was utilized. The effectiveness of the injection on the diffusion of AAV (adeno-associated virus) within the ganglion was assessed by histopathology at postoperative day 21. Results: Behavioral tests showed that neither motor nor sensory abilities were affected by saline or AAV injections. Meanwhile, the decreased pain threshold of SNI (spared nerve injury) was considerably restored by pharmacological inhibition of DRG neurons. Discussion: Our research achieved a new minimally invasive and intuitive intra-ganglionic injection in mice. In addition, the present protocol may serve as a valuable resource for planning preclinical studies of DRG injection.

Spinal voltage-gated potassium channel Kv1.3 contributes to neuropathic pain via the promotion of microglial M1 polarization and activation of the NLRP3 inflammasome.

BACKGROUD: Studies have shown that the activation of microglia is the main mechanism of neuropathic pain. Kv1.3 channel is a novel therapeutic target for treating neuroinflammatory disorders due to its crucial role in subsets of microglial cells. As such, it may be involved in the processes of neuropathic pain, however, whether Kv1.3 plays a role in neuroinflammation following peripheral nerve injury is unclear. METHOD: The spared nerve injury model (SNI) was used to establish neuropathic pain. Western blot and immunofluorescence were used to examine the effect of Kv1.3 in the SNI rats. PAP-1, a Kv1.3 specific blocker was administered to alleviate neuropathic pain in the SNI rats. RESULTS: Neuropathic pain and allodynia occurred after SNI, the levels of M1 (CD68, iNos) and M2 (CD206, Arg-1) phenotypes were up-regulated in the spinal cord, and the protein levels of NLRP3, caspase-1 and IL-1ß were also increased. Pharmacological blocking of Kv1.3 with PAP-1 alleviated hyperpathia induced by SNI. Meanwhile, intrathecal injection of PAP-1 reduced M1 polarization and decreased NLRP3, caspase-1 and IL-1ß expressions of protein levels. CONCLUSION: Our research indicates that the Kv1.3 channel in the spinal cord contributes to neuropathic pain by promoting microglial M1 polarization and activating the NLRP3 inflammasome.

Dysfunction of the Brain-derived Neurotrophic Factor-Tyrosine Kinase B Signaling Pathway Contributes to Learning and Memory Impairments Induced by Neuroinflammation in Mice.

Accumulating evidence suggests that neuroinflammation is the main mechanism in cognitive dysfunction and that brain-derived neurotrophic factor (BDNF) is involved in learning and memory by binding to tyrosine kinase B (TrkB) receptors. Herein, we tested the roles of the BDNF-TrkB signaling pathway and its downstream cascade in lipopolysaccharide (LPS) induced cognitive dysfunction in mice. Mice were treated with LPS (0.25 mg/kg) for 7 days, and learning and memory function was evaluated by the novel object recognition test (NORT). Western blotting was performed to elucidate roles of the BDNF-TrkB signaling pathway and its downstream cascades in LPS mice. The NORT showed that LPS induced learning and memory deficits in mice. The levels of IL-1ß, IL-6, and TNF-α in the serum and central nervous system decreased in LPS mice. In addition, LPS reduced the protein levels of BDNF, p-TrkB, Bcl-2, p-ERK1/2, p-CaMK2, p-CREB and p-GluR1 and increased the expression of Bax in the hippocampus and medial prefrontal cortex regions. In the entorhinal cortex, the protein levels of BDNF, p-TrkB, Bcl-2, p-CaMK2 and p-CREB were decreased, and the protein level of Bax was increased in LPS mice. Interestingly, 7,8-DHF alleviated these disorders in LPS mice and improved learning and memory function; however, the TrkB antagonist ANA12 effectively reversed effects of 7,8-DHF. Therefore, we conclude that the BDNF-TrkB signaling pathway and its downstream cascades disorders in different regions are main mechanisms of cognitive dysfunction, and 7,8-DHF maybe useful as a new treatment for preventing or treating cognitive dysfunction induced by neuroinflammation in neurodegenerative diseases.