Bidirectional causal relational between frailty and mental illness: a two-sample Mendelian randomization study.

Background: Frailty has been associated with mental illness (MI) observational studies, but the causal relationship between these factors remains uncertain. We aimed to assess the bidirectional causality between frailty and MI by two-sample Mendelian randomization (MR) analyses. Methods: To investigate the causal relationship among them, summary statistics of frailty index (FI) and six types of MI: anxiety, depression, affective disorder, mania, schizophrenia, and obsessive-compulsive disorder (OCD) were included in this MR study. This MR analysis was performed using inverse variance weighting (IVW), MR-Egger regression, and weighted median. The stability of the results was evaluated using Cochran's Q test, MR-Egger intercept test, Funnel Plots, and leave-one-out analysis. Results: Genetic predisposition to FI was significantly associated with increased anxiety (odds ratio [OR] = 1.62, 95% confidence interval [CI] 1.13-2.33, P = 8.18E-03), depression (OR = 1.88, 95% CI 1.30-2.71, P = 8.21E-04), affective disorder (OR = 1.70, 95% CI 1.28-2.27, P = 2.57E-04). However, our study findings do not demonstrate a causal relationship between FI and mania (OR = 1.02, 95% CI 0.99-1.06, P = 2.20E-01), schizophrenia (OR = 1.02, 95% CI 0.07-0.86, P = 9.28E-01). In particular, although the IVW results suggest a potential causal relationship between FI and OCD (OR = 0.64, 95% CI 0.07-0.86, P = 2.85E-02), the directions obtained from the three methods we employed ultimately show inconsistency. Therefore, the result must be interpreted with caution. The results of the reverse MR analysis indicated a statistically significant and causal relationship between anxiety (OR = 1.06, 95% CI 1.01-1.11, P = 2.00E-02), depression (OR = 1.14, 95% CI 1.04-1.26, P = 7.99E-03), affective disorder (OR = 1.15, 95% CI 1.09-1.21, P = 3.39E-07), and schizophrenia (OR = 1.02, 95% CI 1.01-1.04, P = 1.70E-03) with FI. However, our findings do not provide support for a link between mania (OR = 1.46, 95% CI 0.79-2.72, P = 2.27E-01), OCD (OR = 1.01, 95% CI 1.00-1.02, P = 2.11E-01) and an increased risk of FI. Conclusion: The MR results suggest a potential bidirectional causal relationship between FI and anxiety, depression, and affective disorder. Schizophrenia was found to be associated with a higher risk of FI. The evidence was insufficient to support a causal relationship between Fl and other Ml. These findings offer new insights into the development of effective management strategies for frailty and MI.

Cav3.2 T-Type calcium channels downregulation attenuates bone cancer pain induced by inhibiting IGF-1/HIF-1α signaling pathway in the rat spinal cord.

Background: Bone cancer pain (BCP) is one of the most ubiquitous and refractory symptoms of cancer patients that needs to be urgently addressed. Substantial studies have revealed the pivotal role of Cav3.2 T-type calcium channels in chronic pain, however, its involvement in BCP and the specific molecular mechanism have not been fully elucidated. Methods: The expression levels of Cav3.2, insulin-like growth factor 1(IGF-1), IGF-1 receptor (IGF-1R) and hypoxia-inducible factor-1α (HIF-1α) were detected by Western blot in tissues and cells. X-ray and Micro CT used to detect bone destruction in rats. Immunofluorescence was used to detect protein expression and spatial location in the spinal dorsal horn. Electrophoretic mobility shift assay used to verify the interaction between HIF-1α and Cav3.2. Results: The results showed that the expression of Cav3.2 channel was upregulated and blockade of this channel alleviated mechanical allodynia and thermal hyperalgesia in BCP rats. Additionally, inhibition of IGF-1/IGF-1R signaling not only reversed the BCP-induced upregulation of Cav3.2 and HIF-1α, but also decreased nociceptive hypersensitivity in BCP rats. Inhibition of IGF-1 increased Cav3.2 expression levels, which were abolished by pretreatment with HIF-1α siRNA in PC12 cells. Furthermore, nuclear HIF-1α bound to the promoter of Cav3.2 to regulate the Cav3.2 transcription level, and knockdown of HIF-1α suppresses the IGF-1-induced upregulation of Cav3.2 and pain behaviors in rats with BCP. Conclusion: These findings suggest that spinal Cav3.2 T-type calcium channels play a central role during the development of bone cancer pain in rats via regulation of the IGF-1/IGF-1R/HIF-1α pathway.

Comparison of the Efficacy of Short-term Peripheral Nerve Stimulation and Pulsed Radiofrequency for Treating Herpes Zoster Ophthalmicus Neuralgia.

OBJECTIVE: This study aimed to investigate the effect of therapy with peripheral nerve stimulation (PNS) and pulsed radiofrequency (PRF) combined or PNS and PRF separately in patients with herpes zoster ophthalmicus (HZO). MATERIALS AND METHODS: This cohort study included 106 cases of HZO. Three groups were identified according to the type of treatment received: combination therapy (PNS+PRF) (n=38), PRF (n=37), and PNS (n=31). The observations at 0, 1, 2, and 4 weeks; 3 and 6 months; and 1 and 2 years after the operation were analyzed. Observations at each follow-up included baseline characteristics, Numerical Rating Scale (NRS) and the Pittsburgh Sleep Quality Index (PSQI), concomitant pain medication usage, relapse rate, and adverse events. RESULTS: The postoperative NRS of all 3 groups were significantly lower than preoperative scores. The PSQI of the 3 groups was significantly improved postoperatively, and the concomitant pain medication gradually decreased. Regarding long-term efficacy, the pain NRS and PSQI scores of the PNS+PRF and PNS groups were significantly lower than those of the PRF group ( P <0.05), and the relapse rate of the PRF group was higher than that of the PNS+PRF and PNS groups ( P <0.05). No significant difference was observed between the PNS+PRF and the PNS groups. CONCLUSION: Both PNS and PRF treatment of HZO can decrease the pain score, yielding no serious complications. The combination of PNS and PRF or PNS alone resulted in more significant pain relief than treatment with PRF alone. Thus, PNS therapy may be a better treatment option for HZO.

Alterations in local activity and functional connectivity in patients with postherpetic neuralgia after short-term spinal cord stimulation.

Introduction: The efficacy of short-term spinal cord stimulation (stSCS) as a treatment for neuropathic pain in patients with postherpetic neuralgia (PHN) has already been validated. However, the potential alterations in brain functionality that are induced by such treatment have yet to be completely elucidated. Methods: This study use resting-state functional magnetic resonance imaging (rs-fMRI) to detect the changes in regional homogeneity (ReHo) and degree centrality (DC) related to stimulator-induced pain relief in patients with PHN. A total of 10 patients with PHN underwent an MRI protocol at baseline and after stSCS. Alterations in ReHo and DC were then compared between baseline and after stSCS. We investigated the relationship between clinical parameters and functional changes in the brain. Results: Clinical parameters on pain, emotion, and sleep quality were correlated with ReHo and DC. ReHo and DC were significantly altered in the middle temporal gyrus, precuneus, superior frontal gyrus, supramarginal gyrus, inferior parietal lobule, rolandic operculum, middle occipital gyrus, superior parietal gyrus, and the precentral gyrus after stSCS. A significant correlation was detected between ReHo changes in the middle occipital gyrus, precuneus, inferior parietal gyrus, and changes in pain, emotion, and sleep quality. A significant negative correlation was detected between DC changes in the middle temporal gyrus, rolandic operculum, supramarginal gyrus, precuneus, inferior parietal gyrus, and changes in pain, emotion, and sleep quality. Conclusion: This study found that stSCS is able to induce ReHo and DC changes in patients with PHN, thus suggesting that stSCS can change brain function to alleviate pain, sleep, and emotional disorder.

The Analysis of Percutaneous Balloon Compression on Efficacy and Negative Emotion in the Treatment of Recurrent Trigeminal Neuralgia After Surgical Procedures.

BACKGROUND: Recurrent trigeminal neuralgia (TN) after surgical operations can be quite difficult to treat, and treatment measures have not been standardized. Patients often have long-term, repeated severe pain, which may easily cause anxiety and depression and can exert a negative effect on the quality of life. Despite the known efficacy of percutaneous balloon compression (PBC) for TN, it is unclear whether PBC can be used as the preferred surgical treatment for postoperative recurrent TN and effectively improve patients' negative emotions. OBJECTIVES: This study aimed to evaluate the clinical curative effect of PBC in patients with postoperative recurrent TN and analyze the improvement in conditions such as anxiety, depression, and sleep disorders. STUDY DESIGN: Retrospective study. SETTING: Center of Pain Medicine, Department of Anesthesiology, pain, and Perioperative Medicine, the First Affiliated Hospital of Zhengzhou University. METHODS: Clinical data from 121 postoperative recurrent TN patients who underwent PBC between August 2017 and June 2019 were retrospectively reviewed and analyzed. The Barrow Neurological Institute pain intensity (BNI-P) score was used to measure the severity of pain. The Hospital Anxiety and Depression Scale (HADS) and Pittsburgh Sleep Quality Index (PSQI) were used to evaluate anxiety, depression, and sleep status. RESULTS: On postoperative day 1, 104 patients (86.0%) reported no pain, 9 patients (7.4%) had occasional pain that did not require medication, and 8 patients (6.6%) experienced no significant pain relief. The total efficacy was 93.4%. Moreover, 3 patients (2.5%) reported significant pain relief 2 weeks postoperatively. Within a follow-up time of 12 months, 101 (83.5%) patients remained pain-free, while 5 patients (4.1%) experienced recurrence. Taking into account economic factors, the patients were tolerant to pain after taking medication and did not undergo repeated PBC. Forty-six patients (38.0%) suffered from anxiety, 70 patients (57.9%) had depression, and 62 patients (51.2%) had poor sleep quality preoperatively. There were significant improvements in anxiety, depression, and sleep status postoperatively compared with preoperatively. Postoperative side effects included facial numbness in 115 patients (95.0%), masticatory muscle weakness in 86 patients (71.1%), herpes simplex in 18 patients (14.9%), and diplopia secondary to abducens nerve palsy in 2 patients (1.7%). None of the patients had corneal anesthesia, anesthesia dolorosa, aseptic meningitis, cerebrospinal fluid leakage, subarachnoid hemorrhage, carotid cavernous fistula, or death in this study. LIMITATIONS: This study was a single-center retrospective study, the sample size was small, and the follow-up time was relatively short. Therefore, the long-term efficacy of PBC for postoperative recurrent TN needs further evaluation from multiple centers with a large sample size and long-term follow-up. CONCLUSIONS: PBC is a minimally invasive, safe, and effective procedure. Moreover, it significantly improves the symptoms of anxiety, depression, and sleep quality caused by TN, so it appears to be regarded as an optimized choice for patients with recurrent TN after surgical procedures.

Downregulation of lncRNA FIRRE relieved the neuropathic pain of female mice by suppressing HMGB1 expression.

Long non-coding RNAs are novel regulators in neuropathic pain. In this study, we aimed to explore the role and the mechanism of lncRNA FIRRE in regulating the secretion of microglial cells-derived proinflammatory cytokines in neuropathic pain. The female mouse model of neuropathic pain was established by bilateral chronic constriction injury (CCI) surgery. The mouse primary microglial cells were induced by lipopolysaccharide (LPS). The interaction between FIRRE and high mobility group box 1 (HMGB1) was assessed by RNA immunoprecipitation, RNA pull-down, and ubiquitination assays. FIRRE expression was upregulated in the spinal cord tissue of female CCI mice and LPS-induced microglial cells. The concentrations of IL-1ß, TNF-α, and IL-6 from LPS-induced microglial cells were reduced by FIRRE knockdown. FIRRE bound to HMGB1 and negatively regulated its protein level. The ubiquitination degradation of HMGB1 was promoted by FIRRE silence. The HMGB1 over-expression reversed the inhibitory effect of FIRRE silence on the secretion of IL-1ß, TNF-α, and IL-6 from LPS-induced microglial cells. The in vivo experiment showed that FIRRE knockdown alleviated neuropathic pain of CCI female mice. Our findings indicated that lncRNA FIRRE downregulation inhibits the secretion of microglial cells-derived proinflammatory cytokines by decreasing HMGB1 expression, thereby relieving neuropathic pain of female mice.

Spinal Cord Stimulation in the Treatment of Pediatric Erythromelalgia.

BACKGROUND: In children, erythromelalgia is a rare but difficult to manage condition that results in bilateral episodic pain and redness in distal extremities. It is heat intolerant and relieved by cooling. Management of erythromelalgia is difficult and requires a complex multidisciplinary approach. CASE DESCRIPTION: We present a case of successful treatment of erythromelalgia with short-term spinal cord stimulation in a 12-year-old girl. The patient had severe burning pain, having undergone trials of multiple medical therapies before presenting to our department. Dual-lead spinal cord stimulator electrodes were successfully implanted without complication, leading to excellent pain control, now 8 months postimplant. CONCLUSIONS: This case spurs interest for future research in neuromodulation as part of the multimodal regimen to treat pediatric erythromelalgia.

The Roles of Chemokine CXCL13 in the Development of Bone Cancer Pain and the Regulation of Morphine Analgesia in Rats.

Chemokines are important regulators of immune, inflammatory, and neuronal responses in peripheral and central pain pathway. The aim of this study was to investigate whether chemokine (C-X-C motif) ligand 13 (CXCL13) and its receptor (C-X-C chemokine receptor type 5, CXCR5) involve in the development of bone cancer pain (BCP) and the regulation of morphine analgesia in rats. The change of pain behaviors in BCP rats were measured by testing paw withdrawal threshold (PWT). The levels of CXCL13, CXCR5 and signal pathway proteins (p-p38, p-ERK and p-AKT etc.) in the spinal cord were measured via western blots. The expression of CXCL13 and CXCR5 in spinal cord was increased in BCP rats. The BCP rats showed decrease of PWTs, which was relieved by CXCR5i. Intrathecally injection of murine recombinant CXCL13 (mrCXCL13) decreased the PWTs of BCP rats and opposed morphine-induced analgesia in BCP rats. In BCP rats, the signal pathway proteins (p38, ERK and AKT) in the spinal cord were activated. CXCL13 and morphine had contrary effect on the phosphorylation of these proteins. MrCXCL13 directly increased the levels of p-p38, p-ERK and p-AKT in BCP rats. However, morphine decreased the levels of these proteins in BCP rats. While blocking the activation of p-p38, p-ERK and p-AKT, morphine analgesia was enhanced. These results suggest CXCL13 participated in bone cancer pain and opposed morphine analgesia via p38, ERK and AKT pathways. It may be a target to enhance pain management in cancer pain patients.