Clinical efficacy and metabolomic analysis of ozone major autohemotherapy for the treatment of herpes zoster.

Introduction: It is essential to understand the underlying changes in the patients' metabolic profiles that may be indicative of the therapy's effectiveness. Aim: To prospectively analyse the clinical efficacy of ozone autohemotherapy in the treatment of acute herpes zoster and investigate its impact on serum metabolomics. Material and methods: A total of 76 patients with acute herpes zoster between May 2018 and June 2020 were enrolled and divided into an experimental group and a control group. The pain location, Numeric Rating Scale (NRS) scores before and after treatment (1 week, 1 month, 3 months, and 6 months post-treatment), medication usage, and Quality of Sleep (QS) scores were prospectively analysed. Additionally, serum metabolomic data were obtained and analysed before and 6 months after the treatment. Results: There were statistically significant differences in the total NRS scores before and after ozone autohemotherapy (p < 0.05). The NRS scores of both groups significantly decreased (p < 0.05). At the 6-month follow-up, no patients were lost, and 83 patients completed the follow-up. The NRS improvement at 1 week, 1 month, 3 months, and 6 months post-treatment in the experimental group was significantly lower than that in the control group (p < 0.05). There was no significant difference in the medication usage (pregabalin or tramadol sustained-release tablets) between the two groups (p > 0.05). One month after treatment, the QS score improvement in the diabetes group was significantly lower than that in the non-diabetes group (p < 0.05). Serum metabolomics analysis revealed three significantly decreased metabolites, namely creatine, adipate, and glucose, after treatment. Conclusions: Ozone autohemotherapy is an effective treatment for acute herpes zoster patients and can rapidly and effectively alleviate pain symptoms in the short term. The changes in serum metabolomics may provide further insights into the treatment mechanism.

Interleukin-17A Acts to Maintain Neuropathic Pain Through Activation of CaMKII/CREB Signaling in Spinal Neurons.

Immunity and neuroinflammation play major roles in neuropathic pain. Spinal interleukin (IL)-17A, as a mediator connecting innate and adaptive immunity, has been shown to be an important cytokine in neuroinflammation and acute neuropathic pain. However, the effects and underlying mechanisms of spinal IL-17A in the maintenance of neuropathic pain remain unknown. This study was designed to investigate whether spinal IL-17A acted to maintain neuropathic pain and to elucidate the underlying mechanisms in IL-17A knockout or wild-type (WT) mice following L4 spinal nerve ligation (L4 SNL). WT mice were treated with anti-IL-17A neutralized monoclonal antibody (mAb) or recombinant IL-17A (rIL-17A). We showed that IL-17A levels were significantly increased 1, 3, 7, and 14 days after SNL in spinal cord. Double immunofluorescence staining showed that astrocytes were the major cellular source of spinal IL-17A. IL-17A knockout or anti-IL-17A mAb treatment significantly ameliorated hyperalgesia 7 days after SNL, which was associated with a significant reduction of p-CaMKII and p-CREB levels in spinal cord, whereas rIL-17A treatment conferred the opposite effects. Furthermore, we showed that blocking CaMKII with KN93 significantly reduced SNL- or rIL-17A-induced hyperalgesia and p-CREB expression. Our in vitro data showed that KN93 also significantly inhibited rIL-17A-induced CREB activation in primary cultured spinal neurons. Taken together, our study indicates that astrocytic IL-17A plays important roles in the maintenance of neuropathic pain through CaMKII/CREB signaling pathway in spinal cord, and thus targeting IL-17A may offer an attractive strategy for the treatment of chronic persistent neuropathic pain.

Rapamycin ameliorates neuropathic pain by activating autophagy and inhibiting interleukin-1ß in the rat spinal cord.

Autophagy acts as an important homoeostatic mechanism by degradation of cytosolic constituents and plays roles in many physiological processes. Recent studies demonstrated that autophagy can also regulate the production and secretion of the proinflammatory cytokine interleukin-1ß (IL-1ß), which plays a critical role in the development and maintenance of neuropathic pain. In the present study, the paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) were significantly decreased after spinal nerve ligation (SNL), and the changes were accompanied by inhibited autophagy in the spinal microglia and increased mRNA and protein levels of IL-1ß in the ipsilateral spinal cord. We then investigated the antinociceptive effect of rapamycin, a widely used autopahgy inducer, on SNL-induced neuropathic pain in rats and found that treatment with intrathecal rapamycin significantly attenuated the mechanical allodynia and thermal hyperalgesia. Moreover, rapamycin significantly enhanced autophagy in the spinal microglia, whereas it reduced the mRNA and protein levels of IL-1ß in the ipsilateral spinal cord. Our results showed that rapamycin could ameliorate neuropathic pain by activating autophagy and inhibiting IL-1ß in the spinal cord.