Efficacy of Mind-Regulating and Depression-Reliving Acupuncture in combination with Radiofrequency Thermocoagulation of Dorsal Root Ganglion for Post-herpetic Neuralgia.

PURPOSE: This study is aimed at evaluating the efficacy of Mind-Regulating and Depression-Relieving Acupuncture in combination with radiofrequency thermocoagulation of DRG for PHN. METHODS: PHN patients who presented to the Pain Department of Affiliated Hospital of Jiaxing University from November 2021 to June 2023 were included. The participants were assigned into two groups using a random number table: Acupuncture + RFTC (Group H, n = 44) group and RFTC (Group C, n = 44) group. The pain numerical rating score (NRS), visual analogue scale scores (VAS), IL-6 , Gal-3, oral dose of tramadol and gabapentin capsules levels were recorded before and after 1, 2, 4, 8 and 12 w of the treatment. RESULTS: After treatment, NRS scores in both groups were significantly lower than pretreatment scores at each time point. Compared with before treatment, the VAS scores at all time points after treatment was increased in both groups. Compared with before treatment, the doses of oral gabapentin capsules and tramadol were reduced in both groups after treatment. Compared with group C, the doses of oral gabapentin capsules and tramadol after the end of the treatment course were significantly reduced in group H. Compared with before treatment, the blood levels of Gal-3 and IL-6 were reduced at all points after treatment in both groups. Compared with group C, the blood Gal-3 and IL-6 levels were significantly reduced in group H. CONCLUSION: Compared with RFTC alone, acupuncture combined with RFTC of DRG has a better therapeutic effect for PHN.

N4-acetylcytidine acetylation of neurexin 2 in the spinal dorsal horn regulates hypersensitivity in a rat model of cancer-induced bone pain.

Cancer-induced bone pain (CIBP) significantly impacts the quality of life and survival of patients with advanced cancer. Despite the established role of neurexins in synaptic structure and function, their involvement in sensory processing during injury has not been extensively studied. In this study using a rat model of CIBP, we observed increased neurexin 2 expression in spinal cord neurons. Knockdown of neurexin 2 in the spinal cord reversed CIBP-related behaviors, sensitization of spinal c-Fos neurons, and pain-related negative emotional behaviors. Additionally, increased acetylation of neurexin 2 mRNA was identified in the spinal dorsal horn of CIBP rats. Decreasing the expression of N-acetyltransferase 10 (NAT10) reduced neurexin 2 mRNA acetylation and neurexin 2 expression. In PC12 cells, we confirmed that neurexin 2 mRNA acetylation enhanced its stability, and neurexin 2 expression was regulated by NAT10. Finally, we discovered that the NAT10/ac4C-neurexin 2 axis modulated neuronal synaptogenesis. This study demonstrated that the NAT10/ac4C-mediated posttranscriptional modulation of neurexin 2 expression led to the remodeling of spinal synapses and the development of conscious hypersensitivity in CIBP rats. Therefore, targeting the epigenetic modification of neurexin 2 mRNA ac4C may offer a new therapeutic approach for the treatment of nociceptive hypersensitivity in CIBP.

PDTC improves cognitive impairment in LPS-induced ARDS by regulating miR-181c/NF-κB axis-mediated neuroinflammation.

BACKGROUND: Cognitive impairment is a severe complication of acute respiratory distress syndrome (ARDS). Emerging studies have revealed the effects of pyrrolidine dithiocarbamate (PDTC) on improving surgery-induced cognitive impairment. The major aim of the study was to investigate whether PDTC protected against ARDS-induced cognitive dysfunction and to identify the underlying mechanisms involved. METHODS: The rat model of ARDS was established by intratracheal instillation of lipopolysaccharide (LPS), followed by treatment with PDTC. The cognitive function of rats was analyzed by the Morris Water Maze, and pro-inflammatory cytokines were assessed by quantitative real-time PCR, enzyme-linked immunosorbent assay, and western blot assays. A dual-luciferase reporter gene assay was performed to identify the relationship between miR-181c and its target gene, TAK1 binding protein 2 (TAB2). RESULTS: The results showed that PDTC improved cognitive impairment and alleviated neuroinflammation in the hippocampus in LPS-induced ARDS model. Furthermore, we demonstrated that miR-181c expression was downregulated in the hippocampus of the ARDS rats, which was restored by PDTC treatment. In vitro studies showed that miR-181c alleviated LPS-induced pro-inflammatory response by inhibiting TAB2, a critical molecule in the nuclear factor (NF)-κB signaling pathway. CONCLUSION: PDTC improves cognitive impairment in LPS-induced ARDS by regulating miR-181c/NF-κB axis-mediated neuroinflammation, providing a potential opportunity for the treatment of this disease.

Curcumin analogue NL04 inhibits spinal cord central sensitization in rats with bone cancer pain by inhibiting NLRP3 inflammasome activation and reducing IL-1ß production.

The management and therapy of bone cancer pain (BCP) remain formidable clinical challenges. Curcumin and its analogues have been shown to have anti-inflammatory and analgesic properties. In the present study, we investigated the efficacy of curcumin analogue NL04 (NL04) in modulating inflammation in spinal dorsal horn (SDH), thereby exploring its potential to reduce central sensitization of BCP in a rat model. Differing doses of NL04 and curcumin were administered intrathecally either once (on day 12 of BCP) or over seven consecutive days (from day 6-12 of BCP). Results indicated that the ED50 for NL04 and curcumin ameliorating BCP-induced mechanical hyperalgesia is 49.08 µg/kg and 489.6 µg/kg, respectively. The analgesic effects at various doses of NL04 lasted between 4 and 8 h, with sustained administration over a week maintaining pain relief for 1-4 days, while also ameliorating locomotor gait via gait analysis and reducing depressive and anxiety-like behaviors via open-field and light-dark transition tests. The analgesic effects at various doses of curcumin lasted 4 h, with sustained administration over a week maintaining pain relief for 0-2 days. ELISA, Western blotting, qPCR, and immunofluorescence assays substantiated that intrathecal administration of NL04 on days 6-12 of BCP dose-dependently lowered spinal IL-1ß and IL-18 levels and significantly reduced the expression of IKKß genes and proteins, as well as the downstream cleavage of the trans-Golgi network (TGN). Whole-cell patch-clamp results demonstrated that NL04 inhibits potassium ion efflux in rat primary spinal neurons. Thus, NL04 exhibits significant analgesic effects in a BCP rat model by downregulating IKKß expression and inhibiting neuronal potassium ion efflux, which, in turn, suppresses the activation of NLRP3 inflammasomes and reduces IL-1ß production, potentially ameliorating pain management in BCP.

Efficacy of Paravertebral Injection of Interferon-α2b Combined with High-Voltage, Long-Term Pulsed Radiofrequency in DRG in Mitigation of Postherpetic Neuralgia: A Retrospective Study.

OBJECTIVE: This investigation aims to evaluate the effectiveness of the paravertebral injection of recombinant human interferon-α2b in conjunction with high-voltage, long-term, pulsed radiofrequency (PRF) in the dorsal root ganglion for the mitigation of postherpetic neuralgia (PHN). METHODS: This retrospective study included 84 individuals with acute PHN. The participants were divided into 3 groups. Group H was treated with interferon-α2b combined with high-voltage long-term PRF. Group C was treated with a combination of high-voltage, long-term PRF and a paravertebral injection (without recombinant human interferon-α2b), and group I was treated with interferon-α2b only. All the patients in the 3 groups were orally administered a 5-mg morphine hydrochloride quick-release tablet when a burst of pain occurred during treatment. The numerical rating scale for pain score, the interleukin-6 and galectin-3 levels, and the incidence of PHN were documented before and after therapy. RESULTS: The pain intensity of all individuals decreased after therapy. Compared with group C, the numerical rating scale scores for group H were significantly reduced at 4, 8, and 12 weeks following therapy, and the PHN incidence was significantly lower. Compared with prior treatment, the recommended dosage of gabapentin capsules and immediate-release morphine hydrochloride tablets was reduced for group H. Compared with group C, the requirement for orally administrated gabapentin capsules and morphine hydrochloride tablets in group H was reduced significantly after treatment. No serious adverse reactions occurred in any of the 3 groups. CONCLUSIONS: Within the context of treatment of acute PHN, the injection of interferon-α2b in conjunction with high-voltage, long-term application of PRF is more effective than PRF or the injection of interferon-α2b alone.

LncRNA 51325 Alleviates Bone Cancer Induced Hyperalgesia Through Inhibition of Pum2.

Background: Bone cancer pain (BCP) represents one of the most challenging comorbidities associated with cancer metastasis. Long non-coding RNAs (lncRNAs) have garnered attention as potential therapeutic agents in managing neuropathic pain. However, their role in the regulation of nociceptive information processing remains poorly understood. In this study, we observed a significant down-regulation of the spinal lncRNA ENSRNOG00000051325 (lncRNA51325) in a rat model of bone cancer pain. Our study sought to elucidate the potential involvement of lncRNA51325 in the development of BCP by modulating the expression of molecules associated with pain modulation. Methods: We established the BCP model by injecting Walker 256 cells into the tibial plateau of rats. We conducted tests on the pain behaviors and anxiety-like responses of rats through von-Frey test, Gait analysis, and Open Field Test. Spinal lumbar expansion was harvested for molecular biology experiments to explore the relationship between lncRNA51325 and Pumilio RNA binding family member 2 (Pum2). Results: Notably, the overexpression of lncRNA51325 effectively attenuated mechanical allodynia in rats afflicted with BCP, whereas the knockdown of lncRNA51325 induced pain behaviors and anxiety-like responses in naïve rats. Additionally, we observed a time-dependent increase in the expression of Pum2 in BCP-afflicted rats, and intrathecal injection of Pum2-siRNA alleviated hyperalgesia. Furthermore, our investigations revealed that lncRNA51325 exerts a negative modulatory effect on Pum2 expression. The overexpression of lncRNA51325 significantly suppressed Pum2 expression in BCP rats, while the knockdown of lncRNA51325 led to elevated Pum2 protein levels in the spinal cord of naïve rats. Subsequent treatment with Pum2-siRNA mitigated the downregulation of lncRNA51325-induced mechanical allodynia in naïve rats. Conclusion: Our findings indicate that lncRNA51325 plays a role in regulating bone cancer pain by inhibiting Pum2 expression, offering a promising avenue for novel treatments targeting nociceptive hypersensitivity induced by bone metastatic cancer.

Effect of CT-Guided Repeated Pulsed Radiofrequency on Controlling Acute/Subacute Zoster-Associated Pain: A Retrospective Cohort Study.

INTRODUCTION: Zoster-associated pain (ZAP) treatment and management is still inadequate. Repeated intervention protocol is often applied to manage ZAP. This study aimed to retrospectively investigate the effect of repeated applications of pulsed radiofrequency therapy on controlling acute/subacute ZAP. METHODS: From March 2019 to December 2021, 150 patients with acute/subacute ZAP who underwent repeated application of pulsed radiofrequency treatment (R-PRF) and pulsed radiofrequency combined paravertebral block interventions (PRF + PVB) in the Pain Department of the affiliated Hospital of Jiaxing University were enrolled. Patients were grouped by intervention protocol and received at least 12 months of follow-up assessments using the Numerical Rating Scale score (NRSs), Pittsburg Sleep Quality Index (PSQI), Simple McGill Pain Questionnaire-2 score (SF-MPQ-2s), and follow-up interventions. RESULTS: Both groups experienced a reduction in the incidence of clinically meaningful ZAP after the intervention therapy. In the R-PRF group, there were 36 cases of clinically meaningful ZAP within the first month post-treatment, while the PRF + PVB group had 38 cases. The incidence of clinically meaningful ZAP, as determined by multivariable generalized estimating equations, was 42.86% in the R-PRF group and 57.58% in the PRF + PVB group during the first month of follow-up. There was a significant difference in the incidence of clinically meaningful ZAP between the two groups after 1 month of treatment (adjusted odds ratio: 0.40; 95% confidence interval: 0.18-0.91; p = 0.03). CONCLUSIONS: Both R-PRF and PRF + PVB treatments effectively relieve pain in patients with acute/subacute ZAP. However, R-PRF may have superior efficacy compared to PRF + PVB in reducing the incidence of clinically meaningful ZAP 1 month after treatment.

Progress in Radiofrequency Therapy for Zoster-Associated Pain About Parameters, Modes, Targets, and Combined Therapy: A Narrative Review.

Zoster-associated pain (ZAP) is a painful condition that significantly impacts a patient's quality of life, often leading to postherpetic neuralgia (PHN). Over 30% of patients with herpes probably experience PHN. However, the understanding and treatment of ZAP remain inadequate. Common interventional treatments include radiofrequency therapy, nerve blocks, epidural block, and spinal cord electrical stimulation. Among these, radiofrequency therapy is widely used for pain control in ZAP, but the standard pulsed radiofrequency technique can still be improved. Researchers have explored different radiofrequency parameters, modes, targets, and combined treatments to enhance the therapeutic effect. In this paper, we review the latest research findings and incorporate our own departmental investigations. We conclude that high-voltage, long-duration pulsed radiofrequency and radiofrequency thermocoagulation therapy have shown improved therapeutic outcomes, despite some remaining limitations. Emphasis is placed on safety in intercostal nerve and extracranial nerve radiofrequency treatments. Combination therapy is also safe and effective; however, many studies have a low grade of evidence. Further high-quality research and systematic reviews are needed.

The involvement of the gut microbiota in postoperative cognitive dysfunction based on integrated metagenomic and metabolomics analysis.

IMPORTANCE: As the population ages and medical technology advances, anesthesia procedures for elderly patients are becoming more common, leading to an increased prevalence of postoperative cognitive dysfunction. However, the etiology and correlation between the gut microbiota and cognitive dysfunction are poorly understood, and research in this area is limited. In this study, mice with postoperative cognitive dysfunction were found to have reduced levels of fatty acid production and anti-inflammatory flora in the gut, and Bacteroides was associated with increased depression, leading to cognitive dysfunction and depression. Furthermore, more specific microbial species were identified in the disease model, suggesting that modulation of host metabolism through gut microbes may be a potential avenue for preventing postoperative cognitive dysfunction.

The success rate and associated risk factors of CT-guided percutaneous radiofrequency sympathectomy in the treatment of primary hyperhidrosis: A retrospective observational trial.

PURPOSE: The aim of this study was to investigate the success rate of surgical technique and associated risk factors based on the follow-up of patients who underwent CT-guided percutaneous radiofrequency sympathectomy (RFS) to treat primary hyperhidrosis (PH). METHODS: 370 patients who underwent RFS for PH treatment between January 2018 and April 2022 were enrolled. Patients responded to a questionnaire and telephone follow-up on the effects of treatment and their electronic medical records and imaging findings were reviewed. Logistic regression was performed to identify risk factors related to the success rate of surgical technique. RESULTS: A temperature difference ≥2 °C before and after procedure was defined as a successful surgical technique. Among the 370 patients (740 sides), 637 sides had successful RFS, and the technical success rate was 86.1 %. Immediately after procedure, 636 sides (85.9 %) were completely dry, 64 (8.7 %) were partially dry, and 40 (5.4 %) were still wet. During the longest follow-up period (54 months), 103 patients relapsed. The median hyperhidrosis disease severity scale score on both sides decreased from 4 to 1 after RFS. According to logistic regression analysis, only the pre-post pulse index was associated with the success rate of surgical technique (odds ratio, 1.14; 95 % confidence interval, 1.06-1.23; p = 0.0004). CONCLUSIONS: We observed that the immediate efficiency and success rate of surgical technique after RFS for PH treatment were relatively high, although there is a possibility of recurrence in the long term. In general, RFS is a safe and effective procedure for alleviating the symptoms of patients with hyperhidrosis.

Development and Validation of a Nomogram to Predict Recurrence of Primary Hyperhidrosis after CT-guided Percutaneous Radiofrequency Sympathectomy.

PURPOSE: To evaluate the recurrence rate of primary hyperhidrosis (PH) after computed tomography (CT)-guided radiofrequency sympathectomy (RFS) and identify risk factors associated with recurrence. MATERIALS AND METHODS: A total of 290 patients with PH who underwent CT-guided RFS were included in this retrospective cohort study. The electronic medical record was reviewed for patients' information and procedural parameters. Follow-ups were conducted for recurrence rate, and Hyperhidrosis Disease Severity Scale was used to assess presence or absence of recurrence. Stepwise regression and the least absolute shrinkage and selection operator regression algorithms were used for feature selection. RESULTS: The recurrence rate 1 year after procedure was 17.6%. Male (hazard ratio [HR], 2.35; 95% confidence interval [CI], 1.08-5.15), low postoperative palm or foot temperature (HR, 0.77; 95% CI, 0.60-0.98), high postoperative heart rate (HR, 1.06; 95% CI, 1.02-1.10), low preoperative and postoperative hospital anxiety and depression score difference (HR, 0.59; 95% CI, 0.43-0.80), and the absence of compensatory hyperhidrosis immediately after procedure (HR, 0.46; 95% CI, 0.22-0.98) were established as independent factors affecting prognosis. A nomogram was built accordingly. The C indices of the training and testing sets were 0.773 and 0.659, respectively. CONCLUSIONS: Follow-up results showed that the recurrence rate of PH treated with CT-guided RFS was low. This study constructed and validated a nomogram to predict the recurrence of PH 1 year after CT-guided RFS, which is convenient for interventionalists to evaluate accurately the prognosis of patients postoperatively and to identify high-risk patients who need more active treatment.

JAG-1/Notch signaling axis in the spinal cord contributes to bone cancer pain in rats.

Notch signal plays an important role in regulating cell-cell interactions with the adjacent cells. However, it remains unknown whether Jagged1 (JAG-1) mediated Notch signaling regulates bone cancer pain (BCP) via the spinal cell interactions mechanism. Here, we showed that intramedullary injection of Walker 256 breast cancer cells increased the expression of JAG-1 in spinal astrocytes and knockdown of JAG-1 reduced BCP. The supplementation of exogenous JAG-1 to the spinal cord induced BCP-like behavior and promoted expression of c-Fos and hairy and enhancer of split homolog-1 (Hes-1) in the spinal cord of the naïve rats. These effects were reversed when the rats were administered intrathecal injections of N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester (DAPT). The intrathecal injection of DAPT reduced BCP and inhibited Hes-1 and c-Fos expression in the spinal cord. Furthermore, our results showed that JAG-1 up-regulated Hes-1 expression by inducing the recruitment of Notch intracellular domain (NICD) to the RBP-J/CSL-binding site located within the Hes-1 promoter sequence. Finally, the intrathecal injection of c-Fos-antisense oligonucleotides (c-Fos-ASO) and administration of sh-Hes-1 to the spinal dorsal horn also alleviated BCP. The study indicates that inhibition of the JAG-1/Notch signaling axis may be a potential strategy for the treatment of BCP.

Understanding the initiation, delivery and processing of bone cancer pain from the peripheral to the central nervous system.

Bone cancer pain is a complex condition characterized by persistent, sudden, spontaneous pain accompanied by hyperalgesia that typically arises from bone metastases or primary bone tumors, causing severe discomfort and significantly diminishing cancer patients' quality of life and confidence in their ability to overcome the disease. It is widely known that peripheral nerves are responsible for detecting harmful stimuli, which are then transmitted to the brain via the spinal cord, resulting in the perception of pain. In the case of bone cancer, tumors and stromal cells within the bone marrow release various chemical signals, including inflammatory factors, colony-stimulating factors, chemokines, and hydrogen ions. Consequently, the nociceptors located at the nerve endings within the bone marrow sense these chemical signals, generating electrical signals that are then transmitted to the brain through the spinal cord. Subsequently, the brain processes these electrical signals in a complex manner to create the sensation of bone cancer pain. Numerous studies have investigated the transmission of bone cancer pain from the periphery to the spinal cord. However, the processing of pain information induced by bone cancer within the brain remains unclear. With the continuous advancements in brain science and technology, the brain mechanism of bone cancer pain would become more clearly understood. Herein, we focus on summarizing the peripheral nerve perception of the spinal cord transmission of bone cancer pain and provide a brief overview of the ongoing research regarding the brain mechanisms involved in bone cancer pain.

Blocking Pannexin-1 Channels Alleviates Thalamic Hemorrhage-Induced Pain and Inflammatory Depolarization of Microglia in Mice.

Central post-stroke pain (CPSP) is a neuropathic pain syndrome that frequently occurs following cerebral stroke. The pathogenesis of CPSP is mainly due to thalamic injury caused by ischemia and hemorrhage. However, its underlying mechanism is far from clear. In the present study, a thalamic hemorrhage (TH) model was established in young male mice by microinjection of 0.075 U of type IV collagenase into the unilateral ventral posterior lateral nucleus and ventral posterior medial nucleus of the thalamus. We found that TH led to microglial pannexin (Panx)-1, a large-pore ion channel, opening within the thalamus accompanied with thalamic tissue injury, pain sensitivities, and neurological deficit, which were significantly prevented by either intraperitoneal injection of the Panx1 blocker carbenoxolone or intracerebroventricular perfusion of the inhibitory mimetic peptide 10Panx. However, inhibition of Panx1 has no additive effect on pain sensitivities upon pharmacological depletion of microglia. Mechanistically, we found that carbenoxolone alleviated TH-induced proinflammatory factors transcription, neuronal apoptosis, and neurite disassembly within the thalamus. In summary, we conclude that blocking of microglial Panx1 channels alleviates CPSP and neurological deficit through, at least in part, reducing neural damage mediated by the inflammatory response of thalamic microglia after TH. Targeting Panx1 might be a potential strategy in the treatment of CPSP.

[Curcumin alleviates nuclear factor-κB/NOD-like receptor protein 3 mediated renal injury caused by acute respiratory distress syndrome through reducing mitochondrial oxidative stress].

OBJECTIVE: To evaluate the effect of curcumin on renal mitochondrial oxidative stress, nuclear factor-κB/NOD-like receptor protein 3 (NF-κB/NLRP3) inflammatory body signaling pathway and tissue cell injury in rats with acute respiratory distress syndrome (ARDS). METHODS: A total of 24 specific pathogen free (SPF)-grade healthy male Sprague-Dawley (SD) rats were randomly divided into control group, ARDS model group, and low-dose and high-dose curcumin groups, with 6 rats in each group. The ARDS rat model was reproduced by intratracheal administration of lipopolysaccharide (LPS) at 4 mg/kg via aerosol inhalation. The control group was given 2 mL/kg of normal saline. The low-dose and high-dose curcumin groups were administered 100 mg/kg or 200 mg/kg curcumin by gavage 24 hours after model reproduction, once a day. The control group and ARDS model group were given an equivalent amount of normal saline. After 7 days, blood samples were collected from the inferior vena cava, and the levels of neutrophil gelatinase-associated lipocalin (NGAL) in serum were determined by enzyme-linked immunosorbent assay (ELISA). The rats were sacrificed, and kidney tissues were collected. Reactive oxygen species (ROS) levels were determined by ELISA, superoxide dismutase (SOD) activity was detected using the xanthine oxidase method, and malondialdehyde (MDA) levels were determined by colorimetric method. The protein expressions of hypoxia-inducible factor-1α (HIF-1α), caspase-3, NF-κB p65, and Toll-like receptor 4 (TLR4) were detected by Western blotting. The mRNA expressions of HIF-1α, NLRP3, and interleukin-1ß (IL-1ß) were detected by reverse transcription-polymerase chain reaction (RT-PCR). Renal cell apoptosis was detected by TdT-mediated dUTP nick end labeling (TUNEL). The morphological changes in renal tubular epithelial cells and mitochondria were observed under a transmission electron microscope. RESULTS: Compared with the control group, the ARDS model group exhibited kidney oxidative stress and inflammatory response, significantly elevated serum levels of kidney injury biomarker NGAL, activated NF-κB/NLRP3 inflammasome signaling pathway, increased kidney tissue cell apoptosis rate, and renal tubular epithelial cell damage and mitochondrial integrity destruction under transmission electron microscopy, indicating successful induction of kidney injury. Following curcumin intervention, the injury to renal tubular epithelial cells and mitochondria in the rats was significantly mitigated, along with a noticeable reduction in oxidative stress, inhibition of the NF-κB/NLRP3 inflammasome signaling pathway, and a significant decrease in kidney tissue cell apoptosis rate, demonstrating a certain dose-dependency. Compared with the ARDS model group, the high-dose curcumin group exhibited significantly reduced serum NGAL levels and kidney tissue MDA and ROS levels [NGAL (µg/L): 13.8±1.7 vs. 29.6±2.7, MDA (nmol/g): 115±18 vs. 300±47, ROS (kU/L): 75±19 vs. 260±15, all P < 0.05], significantly down-regulated protein expressions of HIF-1α, caspase-3, NF-κB p65, and TLR4 in the kidney tissue [HIF-1α protein (HIF-1α/ß-actin): 0.515±0.064 vs. 0.888±0.055, caspase-3 protein (caspase-3/ß-actin): 0.549±0.105 vs. 0.958±0.054, NF-κB p65 protein (NF-κB p65/ß-actin): 0.428±0.166 vs. 0.900±0.059, TLR4 protein (TLR4/ß-actin): 0.683±0.048 vs. 1.093±0.097, all P < 0.05], and significantly down-regulated mRNA expressions of HIF-1α, NLRP3, and IL-1ß [HIF-1α mRNA (2-ΔΔCt): 2.90±0.39 vs. 9.49±1.87, NLRP3 mRNA (2-ΔΔCt): 2.07±0.21 vs. 6.13±1.32, IL-1ß mRNA (2-ΔΔCt): 1.43±0.24 vs. 3.95±0.51, all P < 0.05], and significantly decreased kidney tissue cell apoptosis rate [(4.36±0.92)% vs. (27.75±8.31)%, P < 0.05], and significantly increased SOD activity (kU/g: 648±34 vs. 430±47, P < 0.05). CONCLUSIONS: Curcumin can alleviate kidney injury in ARDS rats, and its mechanism may be related to the increasing in SOD activity, reduction of oxidative stress, and inhibition of the activation of the NF-κB/NLRP3 inflammasome signaling pathway.

Epitranscriptomic profiling of N4-acetylcytidine-related RNA acetylation in the spinal dorsal horn of rat with cancer-induced bone pain.

Recently, epigenetics involved in the regulation of gene expression has become a research hotspot. This study evaluated N4-acetylcytidine (ac4c) RNA acetylation in the spinal dorsal horn (SDH) of rats with cancer-induced bone pain (CIBP). The ac4C-specific RIP sequencing and NAT10-specific RIP sequencing were performed to identify the differences in ac4C acetylation and gene expression in the SDH between CIBP and sham groups, the relationship with the acetylation-modifying enzyme NAT10, and association analysis was performed. By interfering with the NAT10 expression, the relationship between some up-regulated genes and ac4C acetylation in CIBP was verified. In this study, we demonstrated that bone cancer increases the levels of NAT10 and the overall acetylation, inducing differential ac4C patterns in the SDH of rats. Through verification experiments, it was found that ac4C acetylation of some genes is regulated by NAT10, and differential ac4C patterns in RNA determine the expression of this RNA. We exposed that some CIBP-related gene expression was altered in the SDH of rats, which was regulated by differentially expressed ac4C acetylation.

JNK-IN-8 treatment improves ARDS-induced cognitive impairment by inhibiting JNK/NF-κB-mediated NLRP3 inflammasome.

PURPOSE: Cognitive impairment is a critical complication of acute respiratory distress syndrome (ARDS). However, effective interventions are lacking. Growing evidence demonstrates that c-Jun N-terminal kinase (JNK)-mediated neuroinflammation is involved in the development of ARDS. Therefore, we hypothesized that the JNK pathway is involved in ARDS-induced cognitive impairment. METHODS: An in vivo rat model of ARDS was established by treating it with lipopolysaccharide. The cognitive function was assessed by behavioral tests. The levels of pro-inflammatory cytokines, JNK and NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) were analyzed by enzyme-linked immunosorbent assay, western blot, or immunohistochemical analysis. RESULTS: We found that JNK inhibitor 8 (JNK-IN-8) alleviated cognitive impairment, neuroinflammation, and NLRP3 inflammasome activation in the ARDS rat model. Additionally, an in vivo study showed that the protective effect of JNK-IN-8 on cognitive impairment was blocked by nigericin, an NLRP3 activator. CONCLUSIONS: Our data suggest that JNK-IN-8 treatment improves ARDS-induced cognitive impairment by inhibiting the JNK/nuclear factor-κB-mediated NLRP3 inflammasome.

Overexpression of mitogen-activated protein kinase phosphatase-1 in endothelial cells reduces blood-brain barrier injury in a mouse model of ischemic stroke.

Ischemic stroke can cause blood-brain barrier (BBB) injury, which worsens brain damage induced by stroke. Abnormal expression of tight junction proteins in endothelial cells (ECs) can increase intracellular space and BBB leakage. Selective inhibition of mitogen-activated protein kinase, the negative regulatory substrate of mitogen-activated protein kinase phosphatase (MKP)-1, improves tight junction protein function in ECs, and genetic deletion of MKP-1 aggravates ischemic brain injury. However, whether the latter affects BBB integrity, and the cell type-specific mechanism underlying this process, remain unclear. In this study, we established an adult male mouse model of ischemic stroke by occluding the middle cerebral artery for 60 minutes and overexpressed MKP-1 in ECs on the injured side via lentiviral transfection before stroke. We found that overexpression of MKP-1 in ECs reduced infarct volume, reduced the level of inflammatory factors interleukin-1ß, interleukin-6, and chemokine C-C motif ligand-2, inhibited vascular injury, and promoted the recovery of sensorimotor and memory/cognitive function. Overexpression of MKP-1 in ECs also inhibited the activation of cerebral ischemia-induced extracellular signal-regulated kinase (ERK) 1/2 and the downregulation of occludin expression. Finally, to investigate the mechanism by which MKP-1 exerted these functions in ECs, we established an ischemic stroke model in vitro by depriving the primary endothelial cell of oxygen and glucose, and pharmacologically inhibited the activity of MKP-1 and ERK1/2. Our findings suggest that MKP-1 inhibition aggravates oxygen and glucose deprivation-induced cell death, cell monolayer leakage, and downregulation of occludin expression, and that inhibiting ERK1/2 can reverse these effects. In addition, co-inhibition of MKP-1 and ERK1/2 exhibited similar effects to inhibition of ERK1/2. These findings suggest that overexpression of MKP-1 in ECs can prevent ischemia-induced occludin downregulation and cell death via deactivating ERK1/2, thereby protecting the integrity of BBB, alleviating brain injury, and improving post-stroke prognosis.

Upregulation of LncRNA71132 in the spinal cord regulates hypersensitivity in a rat model of bone cancer pain.

ABSTRACT: Bone cancer pain (BCP) is a pervasive clinical symptom which impairs the quality life. Long noncoding RNAs (lncRNAs) are enriched in the central nervous system and play indispensable roles in numerous biological processes, while its regulatory function in nociceptive information processing remains elusive. Here, we reported that functional modulatory role of ENSRNOT00000071132 (lncRNA71132) in the BCP process and sponging with miR-143 and its downstream GPR85-dependent signaling cascade. Spinal lncRNA71132 was remarkably increased in the rat model of bone cancer pain. The knockdown of spinal lncRNA71132 reverted BCP behaviors and spinal c-Fos neuronal sensitization. Overexpression of spinal lncRNA71132 in naive rat generated pain behaviors, which were accompanied by increased spinal c-Fos neuronal sensitization. Furthermore, it was found that lncRNA71132 participates in the modulation of BCP by inversely regulating the processing of miR-143-5p. In addition, an increase in expression of spinal lncRNA71132 resulted in the decrease in expression of miR-143 under the BCP state. Finally, it was found that miR-143-5p regulates pain behaviors by targeting GPR85. Overexpression of miR-143-5p in the spinal cord reverted the nociceptive behaviors triggered by BCP, accompanied by a decrease in expression of spinal GPR85 protein, but no influence on expression of gpr85 mRNA. The findings of this study indicate that lncRNA71132 works as a miRNA sponge in miR-143-5p-mediated posttranscriptional modulation of GPR85 expression in BCP. Therefore, epigenetic interventions against lncRNA71132 may potentially work as novel treatment avenues in treating nociceptive hypersensitivity triggered by bone cancer.

Catalpol ameliorates CFA-induced inflammatory pain by targeting spinal cord and peripheral inflammation.

Chronic, inflammatory pain is an international health concern that severely diminishes individuals' quality of life. Catalpol is an iridoid glycoside derived from the roots of Rehmannia glutinosa that possesses anti-inflammatory, antioxidant, and neuroprotective properties for the treating multiple kinds of disorders. Nevertheless, catalpol's impacts on inflammatory pain and its potential methods of action are still unclear. The purpose of this investigation is to determine the mechanism of catalpol to reduce the inflammatory pain behaviors in a rat model with complete Freund's adjuvant (CFA). Catwalk, Von-Frey, and open field testing were performed for behavioral assessment. Western blot analysis and real-time quantitative PCR (RT-PCR) were employed to identify variations in molecular expression, while immunofluorescence was utilized to identify cellular localization. Catalpol effectively reduced CFA-induced mechanical allodynia and thermal hyperalgesia when injected intrathecally. Moreover, catalpol can regulate the HDAC4/PPAR-γ-signaling pathway in CFA rat spinal cord neurons. Meanwhile catalpol significantly decreased the expression of the NF-κB/NLRP3 inflammatory axis in the spinal cord of CFA rats. In addition, both in vivo and in vitro research revealed that catalpol treatment inhibited astrocyte activation and increase inflammatory factor expression. Interestingly, we also found that catalpol could alleviate peripheral pain by inhibiting tissue inflammation. Taken together, the findings declared that catalpol may inhibit inflammatory pain in CFA rats by targeting spinal cord and peripheral inflammation.