Electroacupuncture exerts prolonged analgesic and neuroprotective effects in a persistent dental pain model induced by multiple dental pulp injuries: GABAergic interneurons-astrocytes interaction.

Pain within the trigeminal system, particularly dental pain, is poorly understood. This study aimed to determine whether single or multiple dental pulp injuries induce persistent pain, its association with trigeminal central nociceptive pathways and whether electroacupuncture (EA) provides prolonged analgesic and neuroprotective effects in a persistent dental pain model. Models of single dental pulp injury (SDPI) and multiple dental pulp injuries (MDPI) were used to induce trigeminal neuropathic pain. The signs of dental pain-related behavior were assessed using the mechanical head withdrawal threshold (HWT). Immunofluorescence and western blot protocols were used to monitor astrocyte activation, changes in apoptosis-related proteins, and GABAergic interneuron plasticity. SDPI mice exhibited an initial marked decrease in HWT from days one to 14, followed by progressive recovery from days 21 to 42. From days 49 to 70, the HWT increased and returned to the control values. In contrast, MDPI mice showed a persistent decrease in HWT from days one to 70. MDPI increased glial fibrillary acidic protein (GFAP) and decreased glutamine synthetase (GS) and glutamate transporter-1 (GLT1) expression in the Vi/Vc transition zone of the brainstem on day 70, whereas no changes in astrocytic markers were observed on day 70 after SDPI. Increased expression of cleaved cysteine-aspartic protease-3 (cleaved caspase-3) and Bcl-2-associated X protein (Bax), along with decreased B-cell lymphoma/leukemia 2 (Bcl-2), were observed at day 70 after MDPI but not after SDPI. The downregulation of glutamic acid decarboxylase (GAD65) expression was observed on day 70 only after MDPI. The effects of MDPI-induced lower HWT from days one to 70 were attenuated by 12 sessions of EA treatment (days one to 21 after MDPI). Changes in astrocytic GFAP, GS, and GLT-1, along with cleaved caspase-3, Bax, Bcl-2, and GAD65 expression observed 70 days after MDPI, were reversed by EA treatment. The results suggest that persistent dental pain in mice was induced by MDPI but not by SDPI. This effect was associated with trigeminal GABAergic interneuron plasticity along with morphological and functional changes in astrocytes. EA exerts prolonged analgesic and neuroprotective effects that might be associated with the modulation of neuron-glia crosstalk mechanisms.

Electroacupuncture improves TBI dysfunction by targeting HDAC overexpression and BDNF-associated Akt/GSK-3ß signaling.

Background: Acupuncture or electroacupuncture (EA) appears to be a potential treatment in acute clinical traumatic brain injury (TBI); however, it remains uncertain whether acupuncture affects post-TBI histone deacetylase (HDAC) expression or impacts other biochemical/neurobiological events. Materials and methods: We used behavioral testing, Western blot, and immunohistochemistry analysis to evaluate the cellular and molecular effects of EA at LI4 and LI11 in both weight drop-impact acceleration (WD)- and controlled cortical impact (CCI)-induced TBI models. Results: Both WD- and CCI-induced TBI caused behavioral dysfunction, increased cortical levels of HDAC1 and HDAC3 isoforms, activated microglia and astrocytes, and decreased cortical levels of BDNF as well as its downstream mediators phosphorylated-Akt and phosphorylated-GSK-3ß. Application of EA reversed motor, sensorimotor, and learning/memory deficits. EA also restored overexpression of HDAC1 and HDAC3, and recovered downregulation of BDNF-associated signaling in the cortex of TBI mice. Conclusion: The results strongly suggest that acupuncture has multiple benefits against TBI-associated adverse behavioral and biochemical effects and that the underlying mechanisms are likely mediated by targeting HDAC overexpression and aberrant BDNF-associated Akt/GSK-3 signaling.

Activation of peripheral TRPM8 mitigates ischemic stroke by topically applied menthol.

BACKGROUND: No reports exist as to neuroprotective effects associated with topical activation of transient receptor potential melastatin 8 (TRPM8), a noted cold receptor. In the present study, we identified whether activating peripheral TRPM8 can be an adjuvant therapy for ischemic stroke. METHODS: Menthol, an agonist of TRPM8, was applied orally or topically to all paws or back of the mouse after middle cerebral artery occlusion (MCAO). We used Trpm8 gene knockout (Trpm8-/-) mice or TRPM8 antagonist and lidocaine to validate the roles of TRPM8 and peripheral nerve conduction in menthol against ischemic stroke. RESULTS: Application of menthol 16% to paw derma attenuated infarct volumes and ameliorated sensorimotor deficits in stroke mice induced by MCAO. The benefits of topically applied menthol were associated with reductions in oxidative stress, neuroinflammation and infiltration of monocytes and macrophages in ischemic brains. Antagonizing TRPM8 or Trpm8 knockout dulls the neuroprotective effects of topically application of menthol against MCAO. Immunohistochemistry analyses revealed significantly higher TRPM8 expression in skin tissue samples obtained from the paws compared with skin from the backs, which was reflected by significantly smaller infarct lesion volumes and better sensorimotor function in mice treated with menthol on the paws compared with the back. Blocking conduction of peripheral nerve in the four paws reversed the neuroprotective effects of topical menthol administrated to paws. On the other hand, oral menthol dosing did not assist with recovery from MCAO in our study. CONCLUSION: Our results suggested that activation of peripheral TRPM8 expressed in the derma tissue of limbs with sufficient concentration of menthol is beneficial to stroke recovery. Topical application of menthol on hands and feet could be a novel and simple-to-use therapeutic strategy for stroke patients.

Electroacupuncture prevents cocaine-induced conditioned place preference reinstatement and attenuates ΔFosB and GluR2 expression.

Acupuncture has been used for treating drug addiction since the 1970s, but little is known about the mechanisms by which acupuncture affects drug cue-induced relapse. The transcription factor delta-FosB (ΔFosB) plays a critical role in behavior and pathology after chronic use of cocaine. ΔFosB regulates glutamate receptor signaling and dendritic spine morphology in animal models. This experimental study compared the effects of electroacupuncture (EA) at acupoints LI4 and LI11 with those of another potentially beneficial intervention, gabapentin (GBP), alone or in combination, on reinstatement of cocaine-induced conditioned place preference (CPP) and levels of ΔFosB and glutamate receptor subunit 2 (GluR2) expression in the nucleus accumbens (NAc). EA at LI4 and LI11 significantly prevented cue-induced cocaine CPP reinstatement, whereas needle insertion without electrical stimulation at these acupoints had no such effect. EA also significantly attenuated cocaine-induced increases in ΔFosB and GluR2 expression in the NAc. Unexpectedly, these effects were reversed when GBP was combined with EA. Treatment with EA at LI4 and LI11 prevented cocaine-induced increases in dendritic spine density in the NAc core and shell. Our results suggest that EA at LI4 and LI11 may prevent cocaine relapse by modulating ΔFosB and GluR2 expression, as well as dendritic spine density.

Noggin Inhibits IL-1ß and BMP-2 Expression, and Attenuates Cartilage Degeneration and Subchondral Bone Destruction in Experimental Osteoarthritis.

Osteoarthritis (OA) is a chronic inflammatory and progressive joint disease that results in cartilage degradation and subchondral bone remodeling. The proinflammatory cytokine interleukin 1 beta (IL-1ß) is abundantly expressed in OA and plays a crucial role in cartilage remodeling, although its role in the activity of chondrocytes in cartilage and subchondral remodeling remains unclear. In this study, stimulating chondrogenic ATDC5 cells with IL-1ß increased the levels of bone morphogenetic protein 2 (BMP-2), promoted articular cartilage degradation, and enhanced structural remodeling. Immunohistochemistry staining and microcomputed tomography imaging of the subchondral trabecular bone region in the experimental OA rat model revealed that the OA disease promotes levels of IL-1ß, BMP-2, and matrix metalloproteinase 13 (MMP-13) expression in the articular cartilage and enhances subchondral bone remodeling. The intra-articular injection of Noggin protein (a BMP-2 inhibitor) attenuated subchondral bone remodeling and disease progression in OA rats. We also found that IL-1ß increased BMP-2 expression by activating the mitogen-activated protein kinase (MEK), extracellular signal-regulated kinase (ERK), and specificity protein 1 (Sp1) signaling pathways. We conclude that IL-1ß promotes BMP-2 expression in chondrocytes via the MEK/ERK/Sp1 signaling pathways. The administration of Noggin protein reduces the expression of IL-1ß and BMP-2, which prevents cartilage degeneration and OA development.

Impact of CCL4 gene polymorphisms upon the progression of lung cancer in a Han Chinese cohort.

Lung cancer is the most common malignancy in China and has a low survival rate amongst Han Chinese. The high mortality is largely attributed to late-stage diagnosis, when treatment is largely ineffective. Identification of genetic variants could potentially assist with earlier diagnosis and thus more effective treatment. Chemokine (C-C motif) ligand 4 (CCL4) plays a critical role as a chemoattractant in tumor development, metastasis and angiogenesis. In this study, we explored three CCL4 single nucleotide polymorphisms (SNPs) (rs1634507, rs1719153, and rs10491121) in 538 patients with lung cancer and 370 healthy, cancer-free controls. Carriers of the GT + TT heterozygote of rs1634507 had a lower risk of lung cancer than wild-type (GG) carriers, while the presence of the AG + GG heterozygote at rs10491121 was associated with a higher risk of lung cancer compared with having the AA genotype. The G/A/G and T/A/A CCL4 haplotypes significantly reduced and increased the risks for lung cancer, respectively. Our study is the first to document correlations between CCL4 polymorphisms and lung cancer development and progression in people of Han Chinese ethnicity.

Associations between WNT1-inducible signaling pathway protein-1 (WISP-1) genetic polymorphisms and clinical aspects of rheumatoid arthritis among Chinese Han subjects.

This study genotyped blood samples from 214 patients with rheumatoid arthritis (RA) and 293 healthy controls for single nucleotide polymorphisms (SNPs) rs2977537, rs2929970, rs2929973, rs2977530, rs1689334 and rs62514004. We want to investigate whether the SNPs in the WNT1-inducible signaling pathway protein 1 (WISP-1) gene may increase the risk of developing RA. We showed that RA disease was more likely with the AA genotype compared with the AG genotype of SNP rs2977537 (adjusted odds ratio [AOR]: 0.54; 95% confidence interval [CI]: 0.34-0.84), and with the TT genotype (AOR: 0.24; 95% CI: 0.13-0.39) or the GG genotype (AOR: 0.05; 95% CI: 0.03-0.10) compared with the GT genotype of rs2929973, and with the AA genotype (AOR: 0.34; 95% CI: 0.22-0.54) or GG genotype (AOR: 0.52; 95% CI: 0.31 to 0.87) vs the AG genotype of rs2977530. Rheumatoid factor positivity was more likely with the AA genotype than with the AG genotype of the rs2977537 polymorphism (AOR: 0.16; 95% CI: 0.16-0.94). High CRP (>8 mg/L) was more likely with the non-AG genotype (AA + GG) than the AG genotype of rs2977537 (AOR: 1.84; 95% CI: 1.05-3.21) and with the AA genotype vs the AG genotype of rs2977530 (AOR: 2.62; 95% CI: 1.35-5.09). Compared with the AG genotype, the AA genotype of rs2929970 was more likely to require prednisolone (AOR: 0.49; 95% CI: 0.27-0.88), while the AG genotype was more likely than the AA genotype of SNP rs2977530 to require TNF-α inhibitors (AOR: 2.07; 95% CI: 1.08 to 3.98). WISP-1 may be a diagnostic marker and therapeutic target for RA therapy.

Impact of WNT1-inducible signaling pathway protein-1 (WISP-1) genetic polymorphisms and clinical aspects of breast cancer.

Breast cancer is the most common diagnosed malignancy in women. This study genotyped blood samples from 236 Han Chinese women with breast cancer and 128 healthy controls for single nucleotide polymorphisms (SNPs) rs2977537, rs2929970, rs2929973, rs2977530, and rs62514004, to determine whether these WNT1-inducible signaling pathway protein 1 (WISP-1) genetic polymorphisms increase the risk of developing breast cancer. Compared with wild-type (AA) carriers, those carrying the WISP1 rs62514004 AG or AG + GG genetic variants had a greater risk of developing breast cancer. In an evaluation of the association between clinicopathological aspects and the WISP1 SNP rs62514004 in the breast cancer cohort, patients with the GG genotype were less likely than those with the AA genotype to develop stage III/IV disease. Patients carrying the WISP1 rs2929973 GG + TT variant were almost twice as likely as those carrying the GT genotype to have estrogen receptor (ER)- and progesterone receptor (PR)-positive tumors, while those with the WISP1 rs62514004 AG + GG genetic variants were around twice as likely as those with the AA genotype to have HER2-positive tumors. This study details risk associations between WISP1 SNPs and breast cancer susceptibility in women of Han Chinese ethnicity.

Interleukin-1ß induces fibroblast growth factor 2 expression and subsequently promotes endothelial progenitor cell angiogenesis in chondrocytes.

Arthritis is a process of chronic inflammation that results in joint damage. IL (interleukin)-1ß is an inflammatory cytokine that acts as a key mediator of cartilage degradation, and is abundantly expressed in arthritis. Neovascularization is one of the pathological characteristics of arthritis. However, the role of IL-1ß in the angiogenesis of chondrocytes remains unknown. In the present study, we demonstrate that stimulating chondrocytes (ATDC5) with IL-1ß increased the expression of FGF (fibroblast growth factor)-2, a potent angiogenic inducer, and then promoted EPC (endothelial progenitor cell) tube formation and migration. In addition, FGF-2-neutralizing antibody abolished ATDC5-conditional medium-mediated angiogenesis in vitro, as well as its angiogenic effects in the CAM (chick chorioallantoic membrane) assay and Matrigel plug nude mice model in vivo. IHC (immunohistochemistry) staining from a CIA (collagen-induced arthritis) mouse model also demonstrates that arthritis increased the expression of IL-1ß and FGF-2, as well as EPC homing in articular cartilage. Moreover, IL-1ß-induced FGF-2 expression via IL-1RI (type-1 IL-1 receptor), ROS (reactive oxygen species) generation, AMPK (AMP-activated protein kinase), p38 and NF-κB (nuclear factor κB) pathway has been demonstrated. On the basis of these findings, we conclude that IL-1ß promotes FGF-2 expression in chondrocytes through the ROS/AMPK/p38/NF-κB signalling pathway and subsequently increases EPC angiogenesis. Therefore IL-1ß serves as a link between inflammation and angiogenesis during arthritis.