Contribution of AMPA Receptor-Mediated LTD in LA/BLA-CeA Pathway to Comorbid Aversive and Depressive Symptoms in Neuropathic Pain.

Comorbid anxiety and depressive symptoms in chronic pain are a common health problem, but the underlying mechanisms remain unclear. Previously, we have demonstrated that sensitization of the CeA neurons via decreased GABAergic inhibition contributes to anxiety-like behaviors in neuropathic pain rats. In this study, by using male Sprague Dawley rats, we reported that the CeA plays a key role in processing both sensory and negative emotional-affective components of neuropathic pain. Bilateral electrolytic lesions of CeA, but not lateral/basolateral nucleus of the amygdala (LA/BLA), abrogated both pain hypersensitivity and aversive and depressive symptoms of neuropathic rats induced by spinal nerve ligation (SNL). Moreover, SNL rats showed structural and functional neuroplasticity manifested as reduced dendritic spines on the CeA neurons and enhanced LTD at the LA/BLA-CeA synapse. Disruption of GluA2-containing AMPAR trafficking and endocytosis from synapses using synthetic peptides, either pep2-EVKI or Tat-GluA2(3Y), restored the enhanced LTD at the LA/BLA-CeA synapse, and alleviated the mechanical allodynia and comorbid aversive and depressive symptoms in neuropathic rats, indicating that the endocytosis of GluA2-containing AMPARs from synapses is probably involved in the LTD at the LA/BLA-CeA synapse and the comorbid aversive and depressive symptoms in neuropathic pain in SNL-operated rats. These data provide a novel mechanism for elucidating comorbid aversive and depressive symptoms in neuropathic pain and highlight that structural and functional neuroplasticity in the amygdala may be important as a promising therapeutic target for comorbid negative emotional-affective disorders in chronic pain.SIGNIFICANCE STATEMENT Several studies have demonstrated the high comorbidity of negative affective disorders in patients with chronic pain. Understanding the affective aspects related to chronic pain may facilitate the development of novel therapies for more effective management. Here, we unravel that the CeA plays a key role in processing both sensory and negative emotional-affective components of neuropathic pain, and LTD at the amygdaloid LA/BLA-CeA synapse mediated by GluA2-containing AMPAR endocytosis underlies the comorbid aversive and depressive symptoms in neuropathic pain. This study provides a novel mechanism for elucidating comorbid aversive and depressive symptoms in neuropathic pain and highlights that structural and functional neuroplasticity in the amygdala may be important as a promising therapeutic target for comorbid negative emotional-affective disorders in chronic pain.

Calycosin inhibited autophagy and oxidative stress in chronic kidney disease skeletal muscle atrophy by regulating AMPK/SKP2/CARM1 signalling pathway.

Skeletal muscle atrophy is a common and serious complication of chronic kidney disease (CKD). Oxidative stress and autophagy are the primary molecular mechanisms involved in muscle atrophy. Calycosin, a major component of Radix astragali, exerts anti-inflammatory, anti-oxidative stress and anti-autophagy effects. We investigated the effects and mechanisms of calycosin on skeletal muscle atrophy in vivo and in vitro. 5/6 nephrectomy (5/6 Nx) rats were used as a model of CKD. We evaluated bodyweight and levels of serum creatinine (SCr), blood urea nitrogen (BUN) and serum albumin (Alb). H&E staining, cell apoptosis, oxidative stress biomarkers, autophagosome and LC3A/B levels were performed and evaluated in skeletal muscle of CKD rat. Calycosin treatment improved bodyweight and renal function, alleviated muscle atrophy (decreased the levels of MuRF1 and MAFbx), increased superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activity and reduced malondialdehyde (MDA) levels in skeletal muscle of CKD rats. Importantly, calycosin reduced autophagosome formation, down-regulated the expression of LC3A/B and ATG7 through inhibition of AMPK and FOXO3a, and increased SKP2, which resulted in decreased expression of CARM1, H3R17me2a. Similar results were observed in C2C12 cells treated with TNF-α and calycosin. Our findings showed that calycosin inhibited oxidative stress and autophagy in CKD induced skeletal muscle atrophy and in TNF-α-induced C2C12 myotube atrophy, partially by regulating the AMPK/SKP2/CARM1 signalling pathway.

An Unusual Case of Scalp Metastasis from Breast Cancer.

BACKGROUND: The most common sites of breast cancer metastases are the bone, lung, liver, and brain. Scalp involvement in breast cancer metastasis is extraordinarily rare. CASE DESCRIPTION: This study reports a 52-year-old woman who had a history of malignant right breast cancer and underwent a mastectomy. Positron emission tomography/computed tomography revealed a soft tissue nodule measuring 1 × 0.7 cm located subcutaneously on the top left side of the scalp. A scalp mass excision operation was performed with an extended "S"-shaped incision, and the mass was sent for pathology. Immunohistochemistry showed the following results: CK7: +; ER: 2+, 90%; GATA3: +; GCDFP-15: scattered cells+; mammaglobin: -, napsin A: -; and TTF-1: -. These results were consistent with the characteristics of primary right breast cancer, supporting scalp metastasis from breast cancer. CONCLUSIONS: Scalp metastasis from breast cancer is an exceedingly infrequent phenomenon. Close attention should be paid to soft tissue masses in patients with a healthy appearance and in those with a history of malignant cancer. When neurosurgeons operate on the mass, the circumscription and depth of the tumor must be given further attention.

Salidroside ameliorates endothelial inflammation and oxidative stress by regulating the AMPK/NF-κB/NLRP3 signaling pathway in AGEs-induced HUVECs.

Endothelial dysfunction plays important roles in vascular dysfunction under diabetic conditions. The generation of advanced glycation end products (AGEs), which can induce inflammation and oxidative stress, is pivotal in endothelial dysfunction. Salidroside, a major active compound in Rhodiola rosea, exerts protective effects against vascular diseases. To study the effects and mechanism of salidroside in diabetes-induced vascular endothelial dysfunction, an in vitro model was established with AGEs-induced human umbilical vein endothelial cells (HUVECs). Then, cell viability, cell apoptosis, pro-inflammatory cytokines and oxidative biomarkers were tested to determine the effects of salidroside at 10, 50 and 100 µM doses on AGEs induced HUVECs. Additionally, RNA-Seq and bioinformatics analyses were used to search for the underlying mechanism of salidroside. The results showed that salidroside promoted cell viability and significantly alleviated cell apoptosis in AGEs-induced HUVECs. Furthermore, salidroside remarkably decreased the levels of the pro-inflammatory cytokines TNF-α, IL-1ß and IL-6 and impeded the expression of VCAM-1 and ICAM-1 induced by AGEs. Additionally, salidroside promoted superoxide dismutase (SOD) activity and increased catalase (CAT) and glutathione peroxidase (GSH-Px) levels while inhibiting the intracellular generation of reactive oxygen species (ROS) and malondialdehyde (MDA) in AGEs-induced HUVECs. Importantly, salidroside alleviated endothelial inflammation and oxidative stress by activating AMPK phosphorylation and inhibiting NF-ĸB p65 and NLRP3 inflammasome activation. Therefore, we used compound C, an accepted AMPK inhibitor, to further demonstrate the mechanism. Interestingly, the phenomenon produced by salidroside was abolished. Our findings suggest that salidroside ameliorates AGEs-induced endothelial inflammation and oxidative stress, partially via the AMPK/NF-κB/NLRP3 signaling pathway.

Contribution of microglial reaction to increased nociceptive responses in high-fat-diet (HFD)-induced obesity in male mice.

The progressive increase in the prevalence of obesity in the population can result in increased healthcare costs and demands. Recent studies have revealed a positive correlation between pain and obesity, although the underlying mechanisms still remain unknown. Here, we aimed to clarify the role of microglia in altered pain behaviors induced by high-fat diet (HFD) in male mice. We found that C57BL/6CR mice on HFD exhibited enhanced spinal microglial reaction (increased cell number and up-regulated expression of p-p38 and CD16/32), increased tumor necrosis factor-α (TNF-α) mRNA and brain-derived neurotrophic factor (BDNF) protein expression as well as a polarization of spinal microglial toward a pro-inflammatory phenotype. Moreover, we found that using PLX3397 (a selective colony-stimulating factor-1 receptor (CSF1R) kinase inhibitor) to eliminate microglia in HFD-induced obesity mice, inflammation in the spinal cord was rescued, as was abnormal pain hypersensitivity. Intrathecal injection of Mac-1-saporin (a saporin-conjugated anti-mac1 antibody) resulted in a decreased number of microglia and attenuated both mechanical allodynia and thermal hyperalgesia in HFD-fed mice. These results indicate that the pro-inflammatory functions of spinal microglia have a special relevance to abnormal pain hypersensitivity in HFD-induced obesity mice. In conclusion, our data suggest that HFD induces a classical reaction of microglia, characterized by an enhanced phosphorylation of p-38 and increased CD16/32 expression, which may in part contribute to increased nociceptive responses in HFD-induced obesity mice.

SKA3 promotes cell proliferation and migration in cervical cancer by activating the PI3K/Akt signaling pathway.

BACKGROUND: Cervical cancer (CC) is one of the most common cancers among females worldwide. Spindle and kinetochore-associated complex subunit 3 (SKA3), located on chromosome 13q, was identified as a novel gene involved in promoting malignant transformation in cancers. However, the function and underlying mechanisms of SKA3 in CC remain unknown. Using the Oncomine database, we found that expression of SKA3 mRNA is higher in CC tissues than in normal tissues and is linked with poor prognosis. METHODS: In our study, immunohistochemistry showed increased expression of SKA3 in CC tissues. The effect of SKA3 on cell proliferation and migration was evaluated by CCK8, clone formation, Transwell and wound-healing assays in HeLa and SiHa cells with stable SKA3 overexpression and knockdown. In addition, we established a xenograft tumor model in vivo. RESULTS: SKA3 overexpression promoted cell proliferation and migration and accelerated tumor growth. We further identified that SKA3 is involved in regulating cell cycle progression and the PI3K/Akt signaling pathway via RNA-sequencing (RNA-Seq) and gene set enrichment analyses. Western blotting results revealed that SKA3 overexpression increased levels of p-Akt, cyclin E2, CDK2, cyclin D1, CDK4, E2F1 and p-Rb in HeLa cells. Additionally, the use of an Akt inhibitor (GSK690693) significantly reversed the cell proliferation capacity induced by SKA3 overexpression in HeLa cells. CONCLUSIONS: We suggest that SKA3 overexpression contributes to CC cell growth and migration by promoting cell cycle progression and activating the PI3K-Akt signaling pathway, which may provide potential novel therapeutic targets for CC treatment.

Decreased abundance of TRESK two-pore domain potassium channels in sensory neurons underlies the pain associated with bone metastasis.

Cancer-associated pain is debilitating. Understanding the mechanisms that cause it can inform drug development that may improve quality of life in patients. Here, we found that the reduced abundance of potassium channels called TRESK in dorsal root ganglion (DRG) neurons sensitized nociceptive sensory neurons and cancer-associated pain. Overexpressing TRESK in DRG neurons suppressed tumor-induced neuronal hyperexcitability and pain hypersensitivity in bone metastasis model rats, whereas knocking down TRESK increased neuronal hyperexcitability and pain hypersensitivity in normal rats. Mechanistically, tumor-associated production of vascular endothelial growth factor (VEGF) activated the receptor VEGFR2 on DRGs, which increased the abundance of the calcineurin inhibitor DSCR1, which, in turn, decreased calcineurin-mediated activation of the transcription factor NFAT, thereby reducing the transcription of the gene encoding TRESK. Intrathecal application of exogenous calcineurin to tumor-bearing rats rescued TRESK abundance and abrogated both DRG hyperexcitability and pain hypersensitivity, whereas either inhibition or knockdown of calcineurin in normal rats reduced TRESK abundance and increased DRG excitability and pain sensitivity. These findings identify a potentially targetable mechanism that may cause bone metastasis-associated pain in cancer patients.

BDNF Contributes to Spinal Long-Term Potentiation and Mechanical Hypersensitivity Via Fyn-Mediated Phosphorylation of NMDA Receptor GluN2B Subunit at Tyrosine 1472 in Rats Following Spinal Nerve Ligation.

Previously we have demonstrated that brain-derived neurotrophic factor (BDNF) contributes to spinal long-term potentiation (LTP) and pain hypersensitivity through activation of GluN2B-containing N-methyl-D-aspartate (GluN2B-NMDA) receptors in rats following spinal nerve ligation (SNL). However, the molecular mechanisms by which BDNF impacts upon GluN2B-NMDA receptors and spinal LTP still remain unclear. In this study, we first documented that Fyn kinase-mediated phosphorylation of GluN2B subunit at tyrosine 1472 (pGluN2BY1472) was involved in BDNF-induced spinal LTP and pain hypersensitivity in intact rats. Second, we revealed a co-localization of Fyn and GluN2B-NMDA receptor in cultured dorsal horn neurons, implying that Fyn is a possible intermediate kinase linking BDNF/TrkB signaling with GluN2B-NMDA receptors in the spinal dorsal horn. Furthermore, we discovered that both SNL surgery and intrathecal active Fyn could induce an increased expression of dorsal horn pGluN2BY1472, as well as pain hypersensitivity in response to von Frey filaments stimuli; and more importantly, all these actions were effectively abrogated by pre-treatment with either PP2 or ifenprodil to respectively inhibit Fyn kinase and GluN2B-NMDA receptors activity. Moreover, we found that intrathecal administration of BDNF scavenger TrkB-Fc prior to SNL surgery, could prevent the nerve injury-induced increase of both pFynY420 and pGluN2BY1472 expression, and also inhibit the mechanical allodynia in neuropathic rats. Collectively, these results suggest that Fyn kinase-mediated pGluN2BY1472 is critical for BDNF-induced spinal LTP and pain hypersensitivity in SNL rats. Therefore, the BDNF-Fyn-GluN2B signaling cascade in the spinal dorsal horn may constitute a key mechanism underlying central sensitization and neuropathic pain development after peripheral nerve injury.

An Oxalyl-CoA Synthetase Is Involved in Oxalate Degradation and Aluminum Tolerance.

Acyl Activating Enzyme3 (AAE3) was identified to be involved in the catabolism of oxalate, which is critical for seed development and defense against fungal pathogens. However, the role of AAE3 protein in abiotic stress responses is unknown. Here, we investigated the role of rice bean (Vigna umbellata) VuAAE3 in Al tolerance. Recombinant VuAAE3 protein has specific activity against oxalate, with Km = 121 ± 8.2 µm and Vmax of 7.7 ± 0.88 µmol min-1 mg-1 protein, indicating it functions as an oxalyl-CoA synthetase. VuAAE3-GFP localization suggested that this enzyme is a soluble protein with no specific subcellular localization. Quantitative reverse transcription-PCR and VuAAE3 promoter-GUS reporter analysis showed that the expression induction of VuAAE3 is mainly confined to rice bean root tips. Accumulation of oxalate was induced rapidly by Al stress in rice bean root tips, and exogenous application of oxalate resulted in the inhibition of root elongation and VuAAE3 expression induction, suggesting that oxalate accumulation is involved in Al-induced root growth inhibition. Furthermore, overexpression of VuAAE3 in tobacco (Nicotiana tabacum) resulted in the increase of Al tolerance, which was associated with the decrease of oxalate accumulation. In addition, NtMATE and NtALS3 expression showed no difference between transgenic lines and wild-type plants. Taken together, our results suggest that VuAAE3-dependent turnover of oxalate plays a critical role in Al tolerance mechanisms.

Pattern Recognition to Prognosticate Endometrial Cancer: The Science Behind the Art of Office Hysteroscopy-A Retrospective Study.

OBJECTIVE: This study aimed to evaluate a specific glomerular pattern for prognostication of endometrial cancer (EC). MATERIALS AND METHODS: The office hysteroscopy's picture and video of 4197 women were reviewed, 48 women who were suspected of type I EC were analyzed: 26 have glomerular pattern (group 1) and 22 without it (group 2). RESULTS: The histopathological grading after hysterectomy with glomerular pattern had grade 2 or grade 3 disease on final histology (n = 25; 96%). The sensitivity and specificity of this test were 84.6% and 81.8%, respectively, with a likelihood ratio of 4:6 in predicting and prognosticating those women who have high-grade tumor or invasive disease. CONCLUSIONS: This hysteroscopic picture might be used as a novel marker for risk stratification of EC.

N-Hydroxycinnamide derivatives of osthole inhibit cell migration and invasion by suppressing Smad2 and Akt pathways in human colorectal adenocarcinoma cells.

WJ1376-1 and WJ1398-1 are new synthetic compounds developed based on the structure of the Chinese herbal medicine osthole. Previously, we reported that WJ1376-1 and WJ1398-1 can induce cell-cycle arrest by activating ATR kinase (ataxia telangiectasia and rad3 related kinase) and inhibiting the phosphorylation of Aurora A kinase. In this study, we determined that WJ1376-1 and WJ1398-1 strongly inhibited the migration and invasion in human colorectal cancer cells at concentrations as low as 1µM. In the transforming growth factor (TGF)-ß-induced epithelial-mesenchymal transition model, WJ1376-1 and WJ1398-1 potently downregulated the transcription factor Snail1, the mesenchymal protein vimentin, and matrix metalloprotease-9, but upregulated the epithelial protein E-cadherin. WJ1376-1 and WJ1398-1 also inhibited the TGF-ß-induced phosphorylation of Smad2 and of Akt at Ser 473, and the nuclear translocation of Smad2 was substantially lower in WJ1376-1- and WJ1398-1-treated cells than it was in control cells. In transient transfection experiments, we observed that WJ1376-1 and WJ1398-1 strongly inhibited TGF-ß-stimulated activity of a Smad reporter. Finally, WJ1376-1 and WJ1398-1 blocked TGF-ß-induced phosphorylation of the TGF-ß Type I receptor (TGF-ßRI). These results suggest that WJ1376-1 and WJ1398-1 inhibit cell migration and invasion by suppressing TGF-ßRI phosphorylation and subsequently hindering both Smad2 and phosphatidylinositol 3-kinase/Akt signaling pathways.

N-Hydroxycinnamide derivatives of osthole presenting genotoxicity and cytotoxicity against human colon adenocarcinoma cells in vitro and in vivo.

Osthole is extracted from the Chinese herbs Cnidium monnieri and Angelica pubescens, and it was found to have antitumor activity in vitro and in vivo. A series of osthole derivatives have been synthesized, and the N-hydroxycinnamide derivatives of osthole, WJ1376-1 and WJ1398-1 were found to have the greatest potential against human colon adenocarcinoma cells. In contrast to the parental osthole, both WJ1376-1 and WJ1398-1 were found to induce multinucleation and polyploidy by microscopic observation and flow cytometry. WJ1376-1 and WJ1398-1 significantly activated ataxia telangiectasia and rad3 related (ATR) kinase, which triggered activation of the checkpoint kinase 2 (Chk2) signaling pathway and then down regulated Cdc25 phosphatase and Cdc2/cyclin B kinase activities. WJ1376-1 and WJ1398-1 also inhibited the phosphorylation of Aurora A kinase, which is associated with important processes during mitosis. The presence of a "comet" DNA fragment and phosphorylation of p53 at Ser 15 clearly indicated that DNA damage occurred with WJ1376-1 and WJ1398-1 treatment. WJ1376-1 and WJ1398-1 ultimately induced apoptosis as evidenced by the upregulation of Bad and activation of caspases-3, -7, and -9. Furthermore, WJ1376-1 and WJ1398-1 also showed a great effect in attenuating tumor growth without affecting the body weight of xenograft nude mice. Taken together, these results suggest that the toxic activities of WJ1376-1 and WJ1398-1 were dissimilar to that of the parental osthole, which can induce cell polyploidy and G2/M cell cycle arrest in colon adenocarcinoma cells and may provide a potential therapeutic target for colon cancer treatment in the future.