Suppressing high mobility group box-1 release alleviates morphine tolerance via the adenosine 5'-monophosphate-activated protein kinase/heme oxygenase-1 pathway.

Opioids, such as morphine, are the most potent drugs used to treat pain. Long-term use results in high tolerance to morphine. High mobility group box-1 (HMGB1) has been shown to participate in neuropathic or inflammatory pain, but its role in morphine tolerance is unclear.

Neutrophil extracellular traps as a unique target in the treatment of chemotherapy-induced peripheral neuropathy.

Background: Chemotherapy-induced peripheral neuropathy (CIPN) is a severe dose-limiting side effect of chemotherapy and remains a huge clinical challenge. Here, we explore the role of microcirculation hypoxia induced by neutrophil extracellular traps (NETs) in the development of CIPN and look for potential treatment.

Methods: The expression of NETs in plasma and dorsal root ganglion (DRG) are examined by ELISA, IHC, IF and Western blotting.

NET-Triggered NLRP3 Activation and IL18 Release Drive Oxaliplatin-Induced Peripheral Neuropathy.

Oxaliplatin is an antineoplastic agent frequently used in the treatment of gastrointestinal tumors. However, it causes dose-limiting sensorimotor neuropathy, referred to as oxaliplatin-induced peripheral neuropathy (OIPN), for which there is no effective treatment. Here, we report that the elevation of neutrophil extracellular traps (NET) is a pathologic change common to both cancer patients treated with oxaliplatin and a murine model of OIPN.

AMPK-autophagy-mediated inhibition of microRNA-30a-5p alleviates morphine tolerance via SOCS3-dependent neuroinflammation suppression.

Background: The development of morphine tolerance is a clinical challenge for managing severe pain. Studies have shown that neuroinflammation is a critical aspect for the development of analgesic tolerance. We found that AMPK-autophagy activation could suppress neuroinflammation and improve morphine tolerance via the upregulation of suppressor of cytokine signaling 3 (SOCS3) by inhibiting the processing and maturation of microRNA-30a-5p.

Rescue of HSP70 in Spinal Neurons Alleviates Opioids-Induced Hyperalgesia via the Suppression of Endoplasmic Reticulum Stress in Rodents.

A major unresolved issue in treating pain is the paradoxical hyperalgesia produced by the gold-standard analgesic morphine and other opioids. Endoplasmic reticulum (ER) stress has been shown to contribute to neuropathic or inflammatory pain, but its roles in opioids-induced hyperalgesia (OIH) are elusive. Here, we provide the first direct evidence that ER stress is a significant driver of OIH.

Inhibition of apoptosis signal-regulating kinase by paeoniflorin attenuates neuroinflammation and ameliorates neuropathic pain.

Background: Neuropathic pain is a serious clinical problem that needs to be solved urgently. ASK1 is an upstream protein of p38 and JNK which plays important roles in neuroinflammation during the induction and maintenance of chronic pain. Therefore, inhibition of ASK1 may be a novel therapeutic approach for neuropathic pain.

Morphine induces dysfunction of PINK1/Parkin-mediated mitophagy in spinal cord neurons implying involvement in antinociceptive tolerance.

The development of opioid-induced analgesic tolerance is a clinical challenge in long-term use for managing chronic pain. The mechanisms of morphine tolerance are poorly understood. Mitochondria-derived reactive oxygen species (ROS) is a crucial signal inducing analgesic tolerance and pain.

Blocking ATP-sensitive potassium channel alleviates morphine tolerance by inhibiting HSP70-TLR4-NLRP3-mediated neuroinflammation.

Background: Long-term use of morphine induces analgesic tolerance, which limits its clinical efficacy. Evidence indicated morphine-evoked neuroinflammation mediated by toll-like receptor 4 (TLR4) - NOD-like receptor protein 3 (NLRP3) inflammasome was important for morphine tolerance. In our study, we investigated whether other existing alternative pathways caused morphine-induced activation of TLR4 in microglia.

Lidocaine alleviates morphine tolerance via AMPK-SOCS3-dependent neuroinflammation suppression in the spinal cord.

Background: Morphine tolerance is a clinical challenge, and its pathogenesis is closely related to the neuroinflammation mediated by Toll-like receptor 4 (TLR4). In Chinese pain clinic, lidocaine is combined with morphine to treat chronic pain. We found that lidocaine sufficiently inhibited neuroinflammation induced by morphine and improved analgesic tolerance on the basis of non-affecting pain threshold.

Grape seed-derived procyanidins alleviate gout pain via NLRP3 inflammasome suppression.

Background: Gout is one of the common inflammatory arthritis which affects many people for inflicting unbearable pain. Macrophage-mediated inflammation plays an important role in gout. The uptake of monosodium urate (MSU) crystals by macrophages can lead to activation of NOD-like receptors containing a PYD 3 (NLRP3) inflammasome, thus accelerating interleukin (IL)-1β production.

Resveratrol suppresses glial activation and alleviates trigeminal neuralgia via activation of AMPK.

Background: Glial activation and neuroinflammation in the spinal trigeminal nucleus (STN) play a pivotal role in the genesis and maintenance of trigeminal neuralgia (TN). Resveratrol, a natural compound from grape and red wine, has a potential anti-inflammatory effect. We hypothesized that resveratrol could significantly suppress neuroinflammation in the STN mediated by glial activation and further relieve TN.

MicroRNA-7 targets Nod-like receptor protein 3 inflammasome to modulate neuroinflammation in the pathogenesis of Parkinson's disease.

Background: α-Synuclein (α-Syn), a pathological hallmark of Parkinson's disease (PD), has been recognized to induce the production of interleukin-1β in a process that depends, at least in vitro, on nod-like receptor protein 3 (NLRP3) inflammasome in monocytes. However, the role of NLRP3 inflammasome activation in the onset of PD has not yet been fully established.

Results: In this study, we showed that NLRP3 inflammasomes were activated in the serum of PD patients and the midbrain of PD model mice.

Procyanidins alleviates morphine tolerance by inhibiting activation of NLRP3 inflammasome in microglia.

Background: The development of antinociceptive tolerance following repetitive administration of opioid analgesics significantly hinders their clinical use. Evidence has accumulated indicating that microglia within the spinal cord plays a critical role in morphine tolerance. The inhibitor of microglia is effective to attenuate the tolerance; however, the mechanism is not fully understood.

Decreased expression of β-nerve growth factor correlated with histological changes in a cryptorchidism rat model.

Background: Nerve growth factor (NGF) is well-known for its important role in the development and maintenance of the nervous system. Along with its neurotrophic role, NGF has been detected in the testis of mouse, rat and human, suggesting an additional non-neurotrophic effect in the male reproductive system. The expression of β-NGF in the undescended testes (cryptorchidism) has not been detected at present.