Kolahdouzan M, Ghazisaeidi S, Tu Y, Muley M, Gambeta E, Salter M (2025) Meningeal macrophages mask incision pain sensitization in male rats. Mol Pain doi: 10.1177/17448069251383593
Objective: To investigate whether CD206+macrophages in the meninges play a role in regulating nociception and pain hypersensitivity.
Summary: The results indicate that while CD206+ meningeal macrophages do not regulate basal nociception in naïve rats, they mask mechanical hypersensitivity in male rats after skin incision injury. Thus, we conclude that in a sex-dependent manner, CD206+ meningeal macrophages prevent the spread of pain hypersensitivity after a minor injury.
Usage: Rats were injected intrathecally (30 μl) with saline, CD206-Saporin (20 μg mannose-receptor antibody and 7 μg of Streptavidin-ZAP in 30 μl), or Rabbit-IgG-Saporin (control).
Yuan M, Zhang L, Zhu H, Xie M (2025) Alteration of BDNF and noradrenergic markers in locus coeruleus in a mouse model of cancer-induced bone pain. PLoS One 20(8):e0330207. doi: 10.1371/journal.pone.0330207 PMID: 40811566
Objective: To examine the expression and localization of BDNF and NE neuron-specific proteins in the locus coeruleus (LC) of mice with cancer-induced bone pain (CIBP).
Summary: CIBP mice exhibited enhanced neuronal activity in the LC, upregulation of noradrenergic markers, and BDNF/TrkB-mediated modulation of noradrenergic neurons. Concurrently, inhibitory signalling was attenuated in the spinal dorsal horn (SDH).
Usage: Selective ablation of noradrenergic neurons via intracerebroventricular anti-DBH-SAP (IT-03) administration reduces mechanical and cold allodynia, suggesting that LC-spinal cord pathway activity is critical for pain modulation.
Windhorst U, Dibaj P (2025) Nociception and acute pain: Neurotransmitters and neuromodulators. Preprints.org preprints202508.0487.v1. doi: 10.20944/preprints202508.0487.v1
Objective: To review the huge variety of additional neurotransmitters, neuromodulators and hormones in the nociceptive and pain system
Summary: Nociception and acute pain are governed by a dynamic interplay of structures and substances, modulated by internal and external factors, and vulnerable to pathological reorganization.
Usage: The injection of anti‐DBH‐SAP induced neurodegeneration restricted to the NA A5 cell group and confirmed by the decrease in the number of NA neurons only in the A5 group.
Lee H, Hor CC, Horwitz LR, Xiong A, Su XY, Soden DR, Yang S, Cai W, Zhang W, Li C, Radcliff C, Dinh A, Fung TLR, Rovcanin I, Pipe KP, Xu XZS, Duan B (2025) A dedicated skin-to-brain circuit for cool sensation in mice. Nat Commun 16(1):6731. doi: 10.1038/s41467-025-61562-y PMID: 40721582
Objective: To investigate the functional contributions of specific spinal dorsal horn neuron subtypes to cold and pain sensation using targeted ablation and optogenetic tools.
Summary: The study identifies Calb1+ spinal neurons as essential mediators of cool sensation in mice. Behavioral and physiological responses following targeted ablation reveal distinct sensory processing roles for various neuronal subtypes.
Usage: Bombesin-SAP (IT-40), or control conjugate Blank-SAP (IT-21), was administered intrathecally at a dose of 400 ng in 10 μL sterile saline to ablate GRPR+ spinal neurons and assess their role in sensory behavior.
Wang D, Wei SN, Zhang L, Lang ZC, Wang SN, Cheng B, Lu Y, Wang X, Wang W, Li FS, Zhang H (2024) Impaired basal forebrain cholinergic neuron gdnf signaling contributes to perioperative sleep deprivation–induced chronicity of postsurgical pain in mice through regulating cholinergic neuronal activity, apoptosis, and autophagy. CNS Nerusci Ther doi: 10.1111/cns.70147 PMID: 39639706
Objective: This study investigated the roles of lateral basal forebrain glial cell line–derived neurotrophic factor (GDNF). The authors researched GDNF and the associated signaling and cholinergic neuron activity, apoptosis, and autophagy dysfunction in sleep deprivation–induced increased risk of chronic postsurgical pain (CPSP) in mice.
Summary: Perioperative sleep deprivation promotes chronicity of postsurgical pain possibly through decreasing basal forebrain GDNF signaling and causing cholinergic neuronal apoptosis and autophagy dysfunction.
Usage: To ablate the basal forebrain cholinergic neurons, 0.4μg/μL of mu p75-SAP (IT-16) in 0.6μL phosphate-buffered saline was used 3 weeks before the Skin/Muscle Incision and Retraction modeling.
Schaible HG, König C, Ebersberger A (2024) Spinal pain processing in arthritis: Neuron and glia (inter)actions. J Neurochem 168(11):3644-3662. doi: 10.1111/jnc.15742 PMID: 36520021
Objective: To address the mechanisms of spinal sensitization evoked by arthritis.
Summary: Neutralization of spinal cytokines by intrathecal interventions attenuates mechanical hyperalgesia. This effect may in part result from local suppression of spinal sensitization and in part from efferent effects which attenuate the inflammatory process in the joint. In summary, arthritis evokes significant spinal hyperexcitability which is likely to contribute to the phenotype of arthritis pain in patients
Usage: Selective microglia destruction with the immunotoxin saporin conjugated to Mac1 antibody (Mac-1-SAP Cat #IT-06, recognizes Mac1 receptor on microglia) attenuated the development of hyperalgesia.
Dai SP, Yang CC, Chin Y, Sun WH (2024) T cell death-associated gene 8-mediated distinct signaling pathways modulate the early and late phases of neuropathic pain. iScience 27(10):110955. doi: 10.1016/j.isci.2024.110955 PMID: 39381739
Objective: To elucidate how T cell death-associated gene 8 (TDAG8)-mediated signaling modulates neuron activities in a mouse model of chronic constriction injury-induced neuropathic pain.
Summary: TDAG8 participated alone in mechanical allodynia induced by constriction injury. TDAG8-Nav1.8 signaling in small-diameter isolectin B4-positive [IB4(+)] neurons initiate mechanical allodynia; it also modulated substance P release from IB4(-) neurons to facilitate the development of early mechanical allodynia. TDAG8-mediated signaling increased medium-to large-diameter IB4(-) neuron activity to maintain late mechanical allodynia; it also modulated substance P release in soma to reduce satellite glial number and Nav1.7 expression, thus attenuating chronic mechanical allodynia.
Usage: Mice were intrathecally injected with IB4-saporin (IB4-SAP, 0.06 mg/mL) or Saporin (0.06 mg/mL)
Meng XT, Song SY, Li Y, Peng S, Zhang LC (2024) Activation of alpha 2 adrenergic receptor of cerebrospinal fluid-contacting nucleus alleviates acute incision pain behavior in rats. Research Square doi: 10.21203/rs.3.rs-4258857/v1
Objective: To study the effects of Dexmedetomidine (DEX) on pain modulation.
Summary: Dexmedetomidine is an alpha 2-adrenergic receptor agonist with sedative, analgesic, and anti-anxiety effects. DEX was analyzed for its effects using a pain neuron knockout model of rats created by ablation of cerebrospinal fluid contacting neurons in the lateral ventricles of rats. DEX inhibited the pain behavior of rats in a dose-dependent manner, and the analgesic effect of DEX was significantly attenuated in CSF-contacting nucleus “knockout” rats.
Usage: CTB-SAP [IT-14] (0.5 µg in 3 µL) was injected into the lateral ventricles (L.V.) of rats over 10 minutes.
Kudsi SQ, Viero FT, Pereira LG, Trevisan G (2024) Involvement of the transient receptor channels in preclinical models of musculoskeletal pain. Curr Neuropharmacol 22(1):72-87. doi: 10.2174/1570159X21666230908094159 PMID: 37694792
Objective: To provide an updated view of the most studied preclinical models of muscle hyperalgesia and the role of transient receptor potential (TRP) in these models.
Summary: The participation of TRPV1, TRPA1, and TRPV4 in different models of musculoskeletal pain was evaluated using pharmacological and genetic tools. All the studies detected the antinociceptive effect of respective antagonists or reduced nociception in knockout mice. Hence, TRPV1, TRPV4, and TRPA1 blockers could potentially be utilized in the future for inducing analgesia in muscle hypersensitivity pathologies.
Usage: NK1-expressing neurons were ablated by SP-SAP (neurotoxin saporin conjugated to substance P) to Vc, and the ablation of NK1-expressing second-order neurons reduced the MGS and bite force nociceptive behaviors.
Donovan LJ, Bridges CM, Nippert AR, Wang M, Wu S, Forman TE, Haight ES, Huck NA, Bond SF, Jordan CE, Gardner AM, Nair RV, Tawfik VL (2024) Repopulated spinal cord microglia exhibit a unique transcriptome and contribute to pain resolution. Cell Rep 43(2):113683. doi: 10.1016/j.celrep.2024.113683 PMID: 38261512
Objective: To study the role of microglia in pain resolution and determine if repopulated microglia actively resolve pain or initiate the transition from acute to chronic pain.
Summary: Pain resolution coincides with microglial repopulation in the spinal cord rather than depletion. Repopulated microglia exhibit unique gene expressions related to phagocytosis and stress response in mice. The study identified potential targets for developing microglial-targeted pain therapeutics by comparing mouse and human spinal cord microglial datasets.
