Sustained Response to Botulinum Toxin Type A in SUNA Sydrome

Pain in axial spondyloarthritis: role of the JAK/STAT pathway

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease that is characterized by new bone formation in the axial musculoskeletal system, with X-ray discriminating between radiographic and non-radiographic forms. Current therapeutic options include non-steroidal anti-inflammatory drugs in addition to biological disease-modifying anti-rheumatic drugs that specifically target tumor necrosis factor-alpha (TNFα) or interleukin (IL)-17. Pain is the most critical symptom for axSpA patients, significantly contributing to the burden of disease and impacting daily life. While the inflammatory process exerts a major role in determining pain in the early phases of the disease, the symptom may also result from mechanical and neuromuscular causes that require complex, multi-faceted pharmacologic and non-pharmacologic treatment, especially in the later phases. In clinical practice, pain often persists and does not respond further despite the absence of inflammatory disease activity. Cytokines involved in axSpA pathogenesis interact directly/indirectly with the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling cascade, a fundamental component in the origin and development of spondyloarthropathies. The JAK/STAT pathway also plays an important role in nociception, and new-generation JAK inhibitors have demonstrated rapid pain relief. We provide a comprehensive review of the different pain types observed in axSpA and the potential role of JAK/STAT signaling in this context, with specific focus on data from preclinical studies and data from clinical trials with JAK inhibitors.

Yaobishu Regulates Inflammatory, Metabolic, Autophagic, and Apoptosis Pathways to Attenuate Lumbar Disc Herniation

Objective

Here, we aimed to explore the main mechanism of Yaobishu (YBS) in lumbar disc herniation (LDH).

Methods and Results

Eighteen compounds that might act on LDH were obtained through a combination of network pharmacology prediction and identification by high-performance liquid chromatography-mass spectrometry. The key compounds were palmitic acid and trans-4-hydroxy-3-methoxycinnamate (cinnamate). KEGG analysis demonstrated that palmitic acid target genes mainly regulate the PPAR signaling pathway, Ras signaling pathway, and fatty acid metabolism. Cinnamate target genes were primarily involved in chemical carcinogenesis-receptor activation, lipid and atherosclerosis, the HIF-1 signaling pathway, and nitrogen metabolism. The rat LDH model was constructed using autologous nucleus pulposus tissue implantation. Differential expression gene (DEGs) related to metabolism (CDKN1A and UHRF1), inflammation (S100A9 and SOCS3), autophagy (DCN and LEPR), and apoptosis (CTSW and BCL2A1) in dorsal root ganglion (DRG) tissues of the control and LDH groups was evaluated by RNA-Seq. TNF-α stimulated DRG neuronal cells were used to establish an in vitro LDH model. YBS, palmitic acid, and cinnamate reduced the expression of substance P, CGRP, S100A9, CTSW, and cleaved caspase-3, while enhancing the expression of CDKN1A, UHRF1, PCNA, Ki67, SOCS3, DCN, LEPR, and BCL2A1, as well as telomerase activity. Pearson's correlation analysis confirmed that DCN was positively correlated with BCL2A1, indicating that autophagy might be negatively correlated with apoptosis in LDH. YBS, palmitic acid, and cinnamate reduced the Siegal neurological score and serum IL-1β and IL-18 levels, while increasing changes in the hind paw mechanical withdrawal threshold. The RNA-Seq results further showed that YBS downregulated S100A9 and CTSW expression, while upregulating SOCS3, CDKN1A, UHRF1, DCN, LEPR, and BCL2A1 expression.

Conclusion

YBS and its compounds, palmitic acid, and cinnamate, attenuated LDH by regulating the inflammatory, metabolic, autophagic, and apoptotic pathways. Our results might improve the theoretical and experimental basis for clinical applications of LDH disease treatment.

Beyond chronic migraine: a systematic review and expert opinion on the off-label use of botulinum neurotoxin type-A in other primary headache disorders

Introduction: Botulinum neurotoxin type-A (BoNTA) is licensed for the treatment of chronic migraine (CM), but it has been tested off-label as a therapeutic choice in other primary headaches (PHs). We aimed to provide a systematic review and expert opinion on BoNTA use in PHs, beyond CM.Areas covered: After providing an overview on PHs and mechanism of BoNTA action, we report the results of a systematic review, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations, of BoNTA therapeutic trials in PHs beyond CM. Studies and results were reviewed and discussed, and levels of evidence were graded. We also collected data on relevant ongoing trials.Expert opinion: Although there are contradictory findings on PHs other than CM, BoNTA may represent a therapeutic option for patients who do not respond to conventional prophylactic treatments. Based on limited available evidence, BoNTA may be considered in refractory tension-type headache, trigeminal autonomic cephalalgias, primary stabbing headache, nummular headache, hypnic headache, and new daily persistent headache, after the primary nature of cephalalgia has been documented and other drugs have failed. Experienced physicians in BoNTA treatment are required to guide the therapeutic protocol for each patient to optimize good and safe outcomes.

Modulation of Pathological Pain by Epidermal Growth Factor Receptor

Chronic pain has been widely recognized as a major public health problem that impacts multiple aspects of patient quality of life. Unfortunately, chronic pain is often resistant to conventional analgesics, which are further limited by their various side effects. New therapeutic strategies and targets are needed to better serve the millions of people suffering from this devastating disease. To this end, recent clinical and preclinical studies have implicated the epidermal growth factor receptor signaling pathway in chronic pain states. EGFR is one of four members of the ErbB family of receptor tyrosine kinases that have key roles in development and the progression of many cancers. EGFR functions by activating many intracellular signaling pathways following binding of various ligands to the receptor. Several of these signaling pathways, such as phosphatidylinositol 3-kinase, are known mediators of pain. EGFR inhibitors are known for their use as cancer therapeutics but given recent evidence in pilot clinical and preclinical investigations, may have clinical use for treating chronic pain. Here, we review the clinical and preclinical evidence implicating EGFR in pathological pain states and provide an overview of EGFR signaling highlighting how EGFR and its ligands drive pain hypersensitivity and interact with important pain pathways such as the opioid system.

The changes of nociception and the signal molecules expression in the dorsal root ganglia and the spinal cord after cold water swimming stress in mice

Several studies have previously reported that exposure to stress provokes behavioral changes, including antinociception, in rodents. In the present study, we studied the effect of acute cold-water (4°C) swimming stress (CWSS) on nociception and the possible changes in several signal molecules in male ICR mice. Here, we show that 3 min of CWSS was sufficient to produce antinociception in tail-flick, hot-plate, von-Frey, writhing, and formalin-induced pain models. Significantly, CWSS strongly reduced nociceptive behavior in the first phase, but not in the second phase, of the formalin-induced pain model. We further examined some signal molecules' expressions in the dorsal root ganglia (DRG) and spinal cord to delineate the possible molecular mechanism involved in the antinociceptive effect under CWSS. CWSS reduced p-ERK, p-AMPKα1, p-AMPKα2, p-Tyk2, and p-STAT3 expression both in the spinal cord and DRG. However, the phosphorylation of mTOR was activated after CWSS in the spinal cord and DRG. Moreover, p-JNK and p-CREB activation were significantly increased by CWSS in the spinal cord, whereas CWSS alleviated JNK and CREB phosphorylation levels in DRG. Our results suggest that the antinociception induced by CWSS may be mediated by several molecules, such as ERK, JNK, CREB, AMPKα1, AMPKα2, mTOR, Tyk2, and STAT3 located in the spinal cord and DRG.