Eicosapentaenoic Acid Modulates Transient Receptor Potential V1 Expression in Specific Brain Areas in a Mouse Fibromyalgia Pain Model.

Pain is an unpleasant sensory and emotional experience accompanied by tissue injury. Often, an individual's experience can be influenced by different physiological, psychological, and social factors. Fibromyalgia, one of the most difficult-to-treat types of pain, is characterized by general muscle pain accompanied by obesity, fatigue, sleep, and memory and psychological concerns. Fibromyalgia increases nociceptive sensations via central sensitization in the brain and spinal cord level. We used intermittent cold stress to create a mouse fibromyalgia pain model via a von Frey test (day 0: 3.69 ± 0.14 g; day 5: 2.13 ± 0.12 g). Mechanical pain could be reversed by eicosapentaenoic acid (EPA) administration (day 0: 3.72 ± 0.14 g; day 5: 3.69 ± 0.13 g). A similar trend could also be observed for thermal hyperalgesia. The levels of elements in the transient receptor potential V1 (TRPV1) signaling pathway were increased in the ascending pain pathway, including the thalamus, medial prefrontal cortex, somatosensory cortex, anterior cingulate cortex, and cerebellum. EPA intake significantly attenuated this overexpression. A novel chemogenetics method was used to inhibit SSC and ACC activities, which presented an analgesic effect through the TRPV1 downstream pathway. The present results provide insights into the role of the TRPV1 signaling pathway for fibromyalgia and its potential as a clinical target.

Chemogenetics Modulation of Electroacupuncture Analgesia in Mice Spared Nerve Injury-Induced Neuropathic Pain through TRPV1 Signaling Pathway.

Neuropathic pain, which is initiated by a malfunction of the somatosensory cortex system, elicits inflammation and simultaneously activates glial cells that initiate neuroinflammation. Electroacupuncture (EA) has been shown to have therapeutic effects for neuropathic pain, although with uncertain mechanisms. We suggest that EA can reliably cure neuropathic disease through anti-inflammation and transient receptor potential V1 (TRPV1) signaling pathways from the peripheral to the central nervous system. To explore this, we used EA to treat the mice spared nerve injury (SNI) model and explore the underlying molecular mechanisms through novel chemogenetics techniques. Both mechanical and thermal pain were found in SNI mice at four weeks (mechanical: 3.23 ± 0.29 g; thermal: 4.9 ± 0.14 s). Mechanical hyperalgesia was partially attenuated by 2 Hz EA (mechanical: 4.05 ± 0.19 g), and thermal hyperalgesia was fully reduced (thermal: 6.22 ± 0.26 s) but not with sham EA (mechanical: 3.13 ± 0.23 g; thermal: 4.58 ± 0.37 s), suggesting EA's specificity. In addition, animals with Trpv1 deletion showed partial mechanical hyperalgesia and no significant induction of thermal hyperalgesia in neuropathic pain mice (mechanical: 4.43 ± 0.26 g; thermal: 6.24 ± 0.09 s). Moreover, we found increased levels of inflammatory factors such as interleukin-1 beta (IL1-ß), IL-3, IL-6, IL-12, IL-17, tumor necrosis factor alpha, and interferon gamma after SNI modeling, which decreased in the EA and Trpv1-/- groups rather than the sham group. Western blot and immunofluorescence analysis showed similar tendencies in the dorsal root ganglion, spinal cord dorsal horn, somatosensory cortex (SSC), and anterior cingulate cortex (ACC). In addition, a novel chemogenetics method was used to precisely inhibit SSC to ACC activity, which showed an analgesic effect through the TRPV1 pathway. In summary, our findings indicate a novel mechanism underlying neuropathic pain as a beneficial target for neuropathic pain.

Electroacupuncture Reduces Fibromyalgia Pain via Neuronal/Microglial Inactivation and Toll-like Receptor 4 in the Mouse Brain: Precise Interpretation of Chemogenetics.

Fibromyalgia (FM) is a complex, chronic, widespread pain syndrome that can cause significant health and economic burden. Emerging evidence has shown that neuroinflammation is an underlying pathological mechanism in FM. Toll-like receptors (TLRs) are key mediators of the immune system. TLR4 is expressed primarily in microglia and regulates downstream signaling pathways, such as MyD88/NF-κB and TRIF/IRF3. It remains unknown whether electroacupuncture (EA) has therapeutic benefit in attenuating FM pain and what role the TLR4 pathway may play in this effect. We compared EA with sham EA to eliminate the placebo effect due to acupuncture. We demonstrated that intermittent cold stress significantly induced an increase in mechanical and thermal FM pain in mice (mechanical: 2.48 ± 0.53 g; thermal: 5.64 ± 0.32 s). EA but not sham EA has an analgesic effect on FM mice. TLR4 and inflammatory mediator-related molecules were increased in the thalamus, medial prefrontal cortex, somatosensory cortex (SSC), and amygdala of FM mice, indicating neuroinflammation and microglial activation. These molecules were reduced by EA but not sham EA. Furthermore, a new chemogenetics method was used to precisely inhibit SSC activity that displayed an anti-nociceptive effect through the TLR4 pathway. Our results imply that the analgesic effect of EA is associated with TLR4 downregulation. We provide novel evidence that EA modulates the TLR4 signaling pathway, revealing potential therapeutic targets for FM pain.

Enhancing cutaneous wound healing: A study on the beneficial effects of nano-gelatin scaffold in rat models.

The challenges in achieving optimal outcomes for wound healing have persisted for decades, prompting ongoing exploration of interventions and management strategies. This study focuses on assessing the potential benefits of implementing a nano-gelatin scaffold for wound healing. Using a rat skin defect model, full-thickness incisional wounds were created on each side of the thoracic-lumbar regions after anesthesia. The wounds were left un-sutured, with one side covered by a gelatin nano-fibrous membrane and the other left uncovered. Wound size changes were measured on days 1, 4, 7, and 14, and on day 14, rats were sacrificed for tissue sample excision, examined with hematoxylin and eosin, and Masson's trichrome stain. Statistical comparisons were performed. The gelatin nanofibers exhibited a smooth surface with a fiber diameter of 260 ± 40 nm and porous structures with proper interconnectivity. Throughout the 14-day experimental period, significant differences in the percentage of wound closure were observed between the groups. Histological scores were higher in the experiment group, indicating less inflammation but dense and well-aligned collagen fiber formation. A preliminary clinical trial on diabetic ulcers also demonstrated promising results. This study highlights the potential of the nano-collagen fibrous membrane to reduce inflammatory infiltration and enhance fibroblast differentiation into myofibroblasts during the early stages of cutaneous wound healing. The nano-fibrous collagen membrane emerges as a promising candidate for promoting wound healing, with considerable potential for future therapeutic applications.

Neuroprotective Potentials of Berberine in Rotenone-Induced Parkinson's Disease-like Motor Symptoms in Rats.

Rotenone (RTN) induces neurotoxicity and motor dysfunction in rats, mirroring the pathophysiological traits of Parkinson's disease (PD), including striatal oxidative stress, mitochondrial dysfunction, and changes in neural structure. This makes RTN a valuable model for PD research. Berberine (BBR), an isoquinoline alkaloid recognized for its antioxidative, anti-inflammatory, and neuroprotective properties, was evaluated for its ability to counteract RTN-induced impairments. Rats received subcutaneous RTN at 0.5 mg/kg for 21 days, resulting in weight loss and significant motor deficits assessed through open-field, bar catalepsy, beam-crossing, rotarod, and grip strength tests. BBR, administered orally at 30 or 100 mg/kg doses, one hour prior to RTN exposure for the same duration, effectively mitigated many of the RTN-induced motor impairments. Furthermore, BBR treatment reduced RTN-induced nitric oxide (NO) and lipid peroxidation (LPO) levels, bolstered antioxidative capacity, enhanced mitochondrial enzyme activities (e.g., succinate dehydrogenase (SDH), ATPase, and the electron transport chain (ETC)), and diminished striatal neuroinflammation and apoptosis markers. Notably, the co-administration of trigonelline (TGN), an inhibitor of the nuclear factor erythroid-2-related factor 2 (Nrf2) pathway, significantly attenuated BBR's protective effects, indicating that BBR's neuroprotective actions are mediated via the Nrf2 pathway. These results underscore BBR's potential in ameliorating motor impairments akin to PD, suggesting its promise in potentially delaying or managing PD symptoms. Further research is warranted to translate these preclinical findings into clinical settings, enhancing our comprehension of BBR's therapeutic prospects in PD.

Acupoint catgut embedding attenuates fibromyalgia pain through attenuation of TRPV1 signaling pathway in mouse.

Objectives: Chronic pain is considered as pain lasting for more than three months and has emerged as a global health problem affecting individuals and society. Chronic extensive pain is the main syndrome upsetting individuals with fibromyalgia (FM), accompanied by anxiety, obesity, sleep disturbances, and depression, Transient receptor potential vanilloid 1 (TRPV1) has been reported to transduce inflammatory and pain signals to the brain. Materials and Methods: Acupoint catgut embedding (ACE) is a novel acupuncture technique that provides continuous effects and convenience. ACE was performed at the bilateral ST36 acupoint. Results: We demonstrated similar pain levels among all groups at baseline. After cold stress, chronic mechanical or thermal nociception was induced (D14: mechanical: 1.85 ± 0.13 g; thermal: 4.85 ± 0.26 s) and reversed in ACE-treated mice (D14: mechanical: 3.99 ± 0.16 g; thermal: 7.42 ± 0.45 s) as well as Trpv1-/- group (Day 14, mechanical: 4.25 ± 0.2 g; thermal: 7.91 ± 0.21 s) mice. Inflammatory mediators were augmented in FM individuals and were abridged after ACE management and TRPV1 gene loss. TRPV1 and its linked mediators were increased in the thalamus (THA), somatosensory cortex (SSC), medial prefrontal cortex (mPFC), and anterior cingulate cortex (ACC) in FM mice. The up-regulation of these mediators was diminished in ACE and Trpv1-/- groups. Conclusion: We suggest that chronic pain can be modulated by ACE or Trpv1-/-. ACE-induced analgesia via TRPV1 signaling pathways may be beneficial targets for FM treatment.

Porphyromonas gingivalis GroEL exacerbates orthotopic allograft transplantation vasculopathy via impairment of endothelial cell function.

Orthotopic allograft transplantation (OAT) is a significant approach to addressing organ failure. However, persistent immune responses to the allograft affect chronic rejection, which induces OAT vasculopathy (OATV) and organ failure. Porphyromonas gingivalis can infiltrate remote organs via the bloodstream, thereby intensifying the severity of cardiovascular, respiratory, and neurodegenerative diseases and cancer. GroEL, a virulence factor of P. gingivalis promotes pro-inflammatory cytokine production in host cells, which assumes to play a pivotal role in the pathogenesis of cardiovascular diseases. Although the aggravation of OATV is attributable to numerous factors, the role of GroEL remains ambiguous. Therefore, this study aimed to investigate the impact of GroEL on OATV. Aortic grafts extracted from PVG/Seac rats were transplanted into ACI/NKyo rats and in vitro human endothelial progenitor cell (EPC) and coronary artery endothelial cell (HCAEC) models. The experimental findings revealed that GroEL exacerbates OATV in ACI/NKyo rats by affecting EPC and smooth muscle progenitor cell (SMPC) function and enabling the anomalous accumulation of collagen. In vitro, GroEL spurs endothelial-mesenchymal transition in EPCs, reduces HCAEC tube formation and barrier function by downregulating junction proteins, accelerates HCAEC aging by lowering mitochondrial membrane potential and respiratory function, and impedes HCAEC migration by modulating cytoskeleton-associated molecules. This study suggests that P. gingivalis GroEL could potentially augment OATV by impacting vascular progenitor and endothelial cell functions.

Hyperglycemia facilitates EV71 replication: Insights into miR-206-mediated regulation of G3BP2 promoting EV71 IRES activity.

Background: Neurotropic virus infections actively manipulate host cell metabolism to enhance virus neurovirulence. Although hyperglycemia is common during severe infections, its specific role remains unclear. This study investigates the impact of hyperglycemia on the neurovirulence of enterovirus 71 (EV71), a neurovirulent virus relying on internal ribosome entry site (IRES)-mediated translation for replication. Methods: Utilizing hSCARB2-transgenic mice, we explore the effects of hyperglycemia in EV71 infection and elucidate the underlying mechanisms. Results: Remarkably, administering insulin alone to reduce hyperglycemia in hSCARB2-transgenic mice results in a decrease in brainstem encephalitis and viral load. Conversely, induced hyperglycemia exacerbates neuropathogenesis, highlighting the pivotal role of hyperglycemia in neurovirulence. Notably, miR-206 emerges as a crucial mediator induced by viral infection, with its expression further heightened by hyperglycemia and concurrently repressed by insulin. The use of antagomiR-206 effectively mitigates EV71-induced brainstem encephalitis and reduces viral load. Mechanistically, miR-206 facilitates IRES-driven virus replication by repressing the stress granule protein G3BP2. Conclusions: Novel therapeutic approaches against severe EV71 infections involve managing hyperglycemia and targeting the miR-206-stress granule pathway to modulate virus IRES activity.