Repetitive transcranial magnetic stimulation regulates neuroinflammation in neuropathic pain

Neuropathic pain (NP) is a frequent condition caused by a lesion in, or disease of, the central or peripheral somatosensory nervous system and is associated with excessive inflammation in the central and peripheral nervous systems. Repetitive transcranial magnetic stimulation (rTMS) is a supplementary treatment for NP. In clinical research, rTMS of 5-10 Hz is widely placed in the primary motor cortex (M1) area, mostly at 80%-90% RMT, and 5-10 treatment sessions could produce an optimal analgesic effect. The degree of pain relief increases greatly when stimulation duration is greater than 10 days. Analgesia induced by rTMS appears to be related to reestablishing the neuroinflammation system. This article discussed the influences of rTMS on the nervous system inflammatory responses, including the brain, spinal cord, dorsal root ganglia (DRG), and peripheral nerve involved in the maintenance and exacerbation of NP. rTMS has shown an anti-inflammation effect by decreasing pro-inflammatory cytokines, including IL-1β, IL-6, and TNF-α, and increasing anti-inflammatory cytokines, including IL-10 and BDNF, in cortical and subcortical tissues. In addition, rTMS reduces the expression of glutamate receptors (mGluR5 and NMDAR2B) and microglia and astrocyte markers (Iba1 and GFAP). Furthermore, rTMS decreases nNOS expression in ipsilateral DRGs and peripheral nerve metabolism and regulates neuroinflammation.

[Effect of underdilated stent on the occurrence of hepatic encephalopathy after transjugular intrahepatic portosystemic shunt creation]

Objective: To evaluate whether underdilated stent could reduce the occurrence of hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS) creation. Methods: A total of 197 patients with decompensated liver cirrhosis, who had underwent TIPS creation at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, were analyzed retrospectively, including 110 males and 87 females with age 25-79 (54±11) years old. Uncovered and covered stents with 8 mm diameter were implanted in all subjects, and then dilated by balloon catheters with 6 mm or 8 mm diameter. The patients were divided into two groups, including underdilated group (6 mm, n=105) and control group (8 mm, n=92).Kaplan-Meier curves were used to illustrate cumulative rate of HE, and the differences were assessed with the log-rank test. Multivariate analyses with a Cox regression model were conducted to explore the risk factors for HE. Results: During a median follow-up period of 29 (12-54) months, 16 (15.2%) patients developed HE in the underdilated group and 27 (29.3%) patients in the control group. There was a significant difference in the cumulative rate of HE (P=0.014), but no statistical differences were found in terms of variceal rebleeding, shunt dysfunction and survival between the two groups (P=0.608, P=0.659, P=0.968). In multivariated analysis, group assignment (underdilated vs. control, HR=0.291, 95%CI 0.125-0.674, P=0.004) was identified as an independent risk factor for HE after TIPS creation. Conclusion: Underdilated TIPS could reduced the risk of HE compared with completely dilated TIPS, with comparable risk of variceal rebleeding, shunt dysfunction and mortality. And it is worthy of applying this technique to a large sample of patients in clinical practice.