Clinical opioids differentially induce co-internalization of µ- and δ-opioid receptors.

Opioid receptors play an important role in mediating the spinal analgesia. The µ-opioid receptor is the major target of opioid drugs widely used in clinics. However, the regulatory mechanisms of analgesic effect and tolerance for clinical µ-opioid receptor-targeting opioids remain to be fully investigated. Previous studies showed the interaction of δ-opioid receptor with µ-opioid receptor to form the µ-opioid receptor/δ-opioid receptor heteromers that could be processed in the degradation pathway after δ-opioid receptor agonist treatment. Here, we showed that clinical µ-opioid receptor-targeting opioids, morphine, fentanyl, and methadone, but not tramadol, caused µ-opioid receptor co-internalization with δ-opioid receptors in both transfected human embryonic kidney 293 cells and primary sensory neurons. Prolonged treatment of morphine led to µ-opioid receptor co-degradation with δ-opioid receptors. Furthermore, fentanyl and methadone, but not tramadol, induced the drug tolerance similar to morphine. Thus, the clinical µ-opioid receptor-targeting opioids including morphine, fentanyl, and methadone induce µ-opioid receptor co-internalization with δ-opioid receptors, which may be involved in the analgesic tolerance of these opioids.

Sox10 escalates vascular inflammation by mediating vascular smooth muscle cell transdifferentiation and pyroptosis in neointimal hyperplasia.

Vascular smooth muscle cells (VSMCs) can transdifferentiate into macrophage-like cells in the context of sustained inflammatory injury, which drives vascular hyperplasia and atherosclerotic complications. Using single-cell RNA sequencing, we identify that macrophage-like VSMCs are the key cell population in mouse neointimal hyperplasia. Sex-determining region Y (SRY)-related HMG-box gene 10 (Sox10) upregulation is associated with macrophage-like VSMC accumulation and pyroptosis in vitro and in the neointimal hyperplasia of mice. Tumor necrosis factor α (TNF-α)-induced Sox10 lactylation in a phosphorylation-dependent manner by PI3K/AKT signaling drives transcriptional programs of VSMC transdifferentiation, contributing to pyroptosis. The regulator of G protein signaling 5 (RGS5) interacts with AKT and blocks PI3K/AKT signaling and Sox10 phosphorylation at S24. Sox10 silencing mitigates vascular inflammation and forestalls neointimal hyperplasia in RGS5 knockout mice. Collectively, this study shows that Sox10 is a regulator of vascular inflammation and a potential control point in inflammation-related vascular disease.

Altered proteomic pattern in platelets of rats with sepsis.

Platelet dysfunction and thrombocytopenia are common responses to sepsis, but how sepsis changes platelet function is not completely understood. This is due, in part, to our lack of understanding of how sepsis alters platelet protein patterns. The aim of the present study, accordingly, was to investigate the response of the platelet proteome to sepsis. We applied proteomic technology to analyze platelet samples of rats with sepsis. Rats were divided into two groups: 1) sham surgery and 2) sepsis induced by cecal ligation and puncture (CLP) surgery. Platelet samples were collected from surviving rats 12 and 24h after surgery, and platelet proteins were separated by two-dimensional electrophoresis (2-DE). Differentially expressed proteins were identified by mass spectrometry (MS). In the CLP group, there were 20 spots that were statistically significantly different at 12h. Of these spots, 16 spots were increased and four spots were decreased. At 24h, there were six spots increased in the CLP group. Of the 26 spots, 12 proteins associated with platelet activation, acute phase proteins, cytoskeleton structure, and energy production were identified. Of interest, alpha-1-antitrypsin precursor (AAT) and ATP synthase beta subunit (ATPB) were both increased at 12 and 24h of sepsis by 2-DE and immunoblotting. By providing the platelet profiles, our results demonstrate that this proteomic approach brings us closer to understanding how platelet dysfunction develops after sepsis.

circ-Sirt1 Decelerates Senescence by Inhibiting p53 Activation in Vascular Smooth Muscle Cells, Ameliorating Neointima Formation.

Vascular smooth muscle cell (VSMC) senescence is a major driver of neointimal formation. We have demonstrated that circ-Sirt1 derived from the SIRT1 gene suppressed VSMC inflammation and neointimal formation. However, the effect of circ-Sirt1 inhibiting inflammation on VSMC senescence during neointimal hyperplasia remains to be elucidated. Here, we showed that circ-Sirt1 was highly expressed in young and healthy arteries, which was decreased in aged arteries and neointima of humans and mice. Overexpression of circ-Sirt1 delayed Ang II-induced VSMC senescence in vitro and ameliorated neointimal hyperplasia in vivo. Mechanically, circ-Sirt1 inhibited p53 activity at the levels of transcription and post-translation modulation. In detail, circ-Sirt1, on the one hand, interacted with and held p53 to block its nuclear translocation, and on the other hand, promoted SIRT1-mediated p53 deacetylation and inactivation. In conclusion, our data suggest that circ-Sirt1 is a novel p53 repressor in response senescence-inducing stimuli, and targeting circ-Sirt1 may be a promising approach to ameliorating aging-related vascular disease.

5'-UTR SNP of FGF13 causes translational defect and intellectual disability.

The congenital intellectual disability (ID)-causing gene mutations remain largely unclear, although many genetic variations might relate to ID. We screened gene mutations in Chinese Han children suffering from severe ID and found a single-nucleotide polymorphism (SNP) in the 5'-untranslated region (5'-UTR) of fibroblast growth factor 13 (FGF13) mRNA (NM_001139500.1:c.-32c>G) shared by three male children. In both HEK293 cells and patient-derived induced pluripotent stem cells, this SNP reduced the translation of FGF13, which stabilizes microtubules in developing neurons. Mice carrying the homologous point mutation in 5'-UTR of Fgf13 showed delayed neuronal migration during cortical development, and weakened learning and memory. Furthermore, this SNP reduced the interaction between FGF13 5'-UTR and polypyrimidine-tract-binding protein 2 (PTBP2), which was required for FGF13 translation in cortical neurons. Thus, this 5'-UTR SNP of FGF13 interferes with the translational process of FGF13 and causes deficits in brain development and cognitive functions.

Preoperative platelet-lymphocyte ratio is a superior prognostic biomarker to other systemic inflammatory response markers in non-small cell lung cancer.

Systemic inflammatory response markers are associated with poor survival in many types of malignances. This study aimed to evaluate the prognostic value of preoperative neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), lymphocyte-monocyte ratio (LMR), and C-reactive protein (CRP) in patients with non-small cell lung cancer (NSCLC).We retrospectively evaluated 254 NSCLC patients who underwent radical surgery between January 2012 and April 2014 in the Sichuan Provincial Cancer Hospital. The cut-off values of NLR, PLR, LMR, and CRP were determined according to the receiver operating characteristic curve, and the correlation of NLR, PLR, LMR, and CRP with prognosis was analyzed based on the cut-off value.The cut-off value for NLR, PLR, LMR, and CRP were 3.18, 122, 4.04, and 8.8, respectively. Univariate analysis showed that age (P = .022), tumor-node-metastasis (TNM) stage (P < .001), T stage (P = .001), and N stage (P < .001) were significantly correlated with disease-free survival (DFS), while age (P = .011), TNM stage (P < .001), T stage (P = .008), N stage (P < .001), and PLR (P = .001) were significantly correlated with overall survival (OS). In multivariate analysis, age (hazard ratio [HR]: 1.564, 95% confidence interval [CI]: 1.087-2.252, P = .016) and TNM stage (HR: 1.704, 95% CI: 1.061-2.735, P = .027) remained independent risk factors affecting DFS, while age (HR: 1.721, 95% CI: 1.153-2.567, P = .008), TNM stage (HR: 2.198, 95% CI: 1.263-3.824, P = .005), and PLR (HR: 1.850, 95% CI: 1.246-2.746, P = .002) were independent risk factors affecting OS.The preoperative PLR is superior to NLR, LMR, and CRP as a biomarker for evaluating the prognosis of patients undergoing curative surgery for NSCLC.

Smooth muscle SIRT1 reprograms endothelial cells to suppress angiogenesis after ischemia.

Objective: Vascular smooth muscle cells (VSMCs) undergo the phenotypic changes from contractile to synthetic state during vascular remodeling after ischemia. SIRT1 protects against stress-induced vascular remodeling via maintaining VSMC differentiated phenotype. However, the effect of smooth muscle SIRT1 on the functions of endothelial cells (ECs) has not been well clarified. Here, we explored the role of smooth muscle SIRT1 in endothelial angiogenesis after ischemia and the underlying mechanisms. Methods: We performed a femoral artery ligation model using VSMC specific human SIRT1 transgenic (SIRT1-Tg) and knockout (KO) mice. Angiogenesis was assessed in in vivo by quantification of the total number of capillaries, wound healing and matrigel plug assays, and in vitro ECs by tube formation, proliferation and migration assays. The interaction of HIF1α with circRNA was examined by using RNA immunoprecipitation, RNA pull-down and in situ hybridization assays. Results: The blood flow recovery was significantly attenuated in SIRT1-Tg mice, and markedly improved in SIRT1-Tg mice treated with SIRT1 inhibitor EX527 and in SIRT1-KO mice. The density of capillaries significantly decreased in the ischemic gastrocnemius of SIRT1-Tg mice compared with SIRT1-KO and WT mice, with reduced expression of VEGFA, which resulted in decreased number of arterioles. We identified that the phenotypic switching of SIRT1-Tg VSMCs was attenuated in response to hypoxia, with high levels of contractile proteins and reduced expression of the synthetic markers and NG2, compared with SIRT1-KO and WT VSMCs. Mechanistically, SIRT1-Tg VSMCs inhibited endothelial angiogenic activity induced by hypoxia via the exosome cZFP609. The cZFP609 was delivered into ECs, and detained HIF1α in the cytoplasm via its interaction with HIF1α, thereby inhibiting VEGFA expression and endothelial angiogenic functions. Meantime, the high cZFP609 expression was observed in the plasma of the patients with atherosclerotic or diabetic lower extremity peripheral artery disease, associated with reduced ankle-brachial index. Knockdown of cZFP609 improved blood flow recovery after hindlimb ischemia in SIRT1-Tg mice. Conclusions: Our findings demonstrate that SIRT1 may impair the plasticity of VSMCs. cZFP609 mediates VSMCs to reprogram endothelial functions, and serves as a valuable indicator to assess the prognosis and clinical outcomes of ischemic diseases.

FGF13 Selectively Regulates Heat Nociception by Interacting with Nav1.7.

The current knowledge about heat nociception is mainly confined to the thermosensors, including the transient receptor potential cation channel V1 expressed in the nociceptive neurons of dorsal root ganglion (DRG). However, the loss of thermosensors only partially impairs heat nociception, suggesting the existence of undiscovered mechanisms. We found that the loss of an intracellular fibroblast growth factor (FGF), FGF13, in the mouse DRG neurons selectively abolished heat nociception. The noxious heat stimuli could not evoke the sustained action potential firing in FGF13-deficient DRG neurons. Furthermore, FGF13 interacted with the sodium channel Nav1.7 in a heat-facilitated manner. FGF13 increased Nav1.7 sodium currents and maintained the membrane localization of Nav1.7 during noxious heat stimulation, enabling the sustained firing of action potentials. Disrupting the FGF13/Nav1.7 interaction reduced the heat-evoked action potential firing and nociceptive behavior. Thus, beyond the thermosensors, the FGF13/Nav1.7 complex is essential for sustaining the transmission of noxious heat signals.

Somatosensory neuron types identified by high-coverage single-cell RNA-sequencing and functional heterogeneity.

Sensory neurons are distinguished by distinct signaling networks and receptive characteristics. Thus, sensory neuron types can be defined by linking transcriptome-based neuron typing with the sensory phenotypes. Here we classify somatosensory neurons of the mouse dorsal root ganglion (DRG) by high-coverage single-cell RNA-sequencing (10 950 ± 1 218 genes per neuron) and neuron size-based hierarchical clustering. Moreover, single DRG neurons responding to cutaneous stimuli are recorded using an in vivo whole-cell patch clamp technique and classified by neuron-type genetic markers. Small diameter DRG neurons are classified into one type of low-threshold mechanoreceptor and five types of mechanoheat nociceptors (MHNs). Each of the MHN types is further categorized into two subtypes. Large DRG neurons are categorized into four types, including neurexophilin 1-expressing MHNs and mechanical nociceptors (MNs) expressing BAI1-associated protein 2-like 1 (Baiap2l1). Mechanoreceptors expressing trafficking protein particle complex 3-like and Baiap2l1-marked MNs are subdivided into two subtypes each. These results provide a new system for cataloging somatosensory neurons and their transcriptome databases.

Pre-treatment with a Xingnaojing preparation ameliorates sevoflurane-induced neuroapoptosis in the infant rat striatum.

Xingnaojing (XNJ), is a standardized Chinese herbal medicine product derived from An Gong Niu Huang Pill. It may be involved in neuroprotection in a number of neurological disorders. Exposure to anesthetic agents during the brain growth spurt may trigger widespread neuroapoptosis in the developing brain. Thus the present study aimed to identify whether there was a neuroprotective effect of XNJ on anesthesia­induced neuroapoptosis. Seven­day­old rats received treatment with 2.1% sevoflurane for 6 h. Rat pups were injected intraperitoneally with 1 or 10 ml/kg XNJ at 0.2, 24 and 48 h prior to sevoflurane exposure. The striata of neonatal rats were collected following administration of anesthesia. Western blotting and immunohistochemistry were used to analyze the expression of activated caspase 3, Bax and phosphorylated protein kinase B (p­AKT) in the striatum. It was found that activated caspase 3 and Bax expression were upregulated in the striatum following sevoflurane treatment. Preconditioning with XNJ attenuated the neuronal apoptosis induced by sevoflurane in a dose­dependent manner. Anesthesia reduced the expression of p­AKT (phosphorylated at sites Thr308 and Ser473) and phosphorylated extracellular­regulated protein kinase (p­ERK) in the striatum. Pre­treatment with XNJ reversed the reduction in p­AKT, but not p­ERK expression. These data suggest that XNJ has an antiapoptotic effect against sevoflurane­induced cell loss in the striatum. It thus holds promise as a safe and effective neuroprotective agent. The action of XNJ on p­AKT may make a significant contribution to its neuroprotective effect.

Sevoflurane inhibits the phosphorylation of ribosomal protein S6 in neonatal rat brain.

Besides neurotoxic effects, inhaled anesthetics might have other adverse effects on the developing brain. Ribosomal protein S6 (rpS6), the first identified ribosomal protein undergoing phosphorylation, has important physiological functions in regulating protein synthesis, cell proliferation, and glucose homeostasis. To date, the function of sevoflurane on rpS6 phosphorylation is unclear. In our present study, we showed that sevoflurane anesthesia inhibited rpS6 phosphorylation in cerebral cortex and CA1 region of the hippocampus. The activity of Akt was detected to be reduced within both cortical and hippocampal regions in the brain with the treatment of sevoflurane. However, the treatment seemed to have no effect on the phosphorylation of mammalian target of rapamycin (mTOR), a downstream effector of Akt. Sevoflurane had a paradoxical effect on ERK activity in the hippocampus and cerebral cortex. Last but not the least, Sevoflurane increased PP1 activity in the cerebral cortex and hippocampus. Thus, the exposure to sevoflurane inhibited dramatically the phosphorylation of rpS6 in neonatal rat brains. The inhibitory effect of sevoflurane on rpS6 phosphorylation might be mediated by the suppression on AKT activity at an mTOR-independent manner and the enhancement of PP1 activity.

Livin modulates the apoptotic effects of vesicular stomatotitis virus in lung adenocarcinoma.

Vesicular stomatitis virus (VSV) has shown promise in cancer treatment. However, it achieved limited effects against lung cancer. Lung cancer has intrinsic mechanisms that render resistance to VSV. In this study, we attempted to explore the expression of the anti-apoptotic factor Livin in lung adenocarcinoma and its possible relationship to VSV vulnerability. We found VSV induced apoptosis in a time- and dose-dependent manner, with the concomitant change in the expression of Livin. We elevated the expression of Livin both transiently and stably, and the cells became insensitive to VSV treatment. We further found the BIR domain of Livin was mainly responsible for its modulation effects. This finding suggested a possible interaction with the second mitochondria-derived activator of caspase (SMAC). The knock-down of SMAC also inhibited apoptosis by VSV. The relationship was confirmed by the co-immunoprecipitation. Finally, we knocked down the endogenous Livin, and the knock-down sensitized cells to VSV treatment. Our results suggested the important role of Livin and its partner molecule in the process of VSV treatment.

IFN-gamma activates cAMP/PKA/CREB signaling pathway in murine peritoneal macrophages.

Interferon-gamma (IFN-gamma) is a macrophage-activating cytokine that serves critical functions in innate and adaptive immunity and is thought to be mediated by the Jak-Stat signaling pathway. The present study establishes for the first time that cyclic adenosine monophosphate, protein kinase A, and cAMP response element-binding protein (cAMP/PKA/CREB) are coregulators of the IFN-gamma signaling pathway. Experimental data indicate that exogenous IFN-gamma stimulated cAMP accumulation and PKA activation in time-dependent and dose-dependent manners in murine peritoneal macrophages. Moreover, IFN-gamma stimulated CREB phosphorylation and CREB DNA binding, which could be significantly attenuated by PKA inhibition with H89. It appears that a novel cAMP/PKA/CREB signaling pathway is activated by IFN-gamma in macrophages, suggesting that an alternate signaling pathway exists in macrophages in response to IFN-gamma.

cAMP elevators inhibit LPS-induced IL-12 p40 expression by interfering with phosphorylation of p38 MAPK in murine peritoneal macrophages.

cAMP mediated signaling may play a suppressive role in immune response. We previously found that the cAMP-elevators (CTx and 8-Br-cAMP) inhibited IL-12, IL-la, IL-6 gene expression, but increased the transcriptional levels of IL-10 and IL-1Ra in LPS-treated murine peritoneal macrophages. The present study examined a possible molecular mechanism involved in cAMP elevators-induced inhibition of IL-12 p40 expression in response to LPS. Our data demonstrated that cAMP elevators downregulated IL-12 p40 mRNA expression and IL-12 p70 production in murine peritoneal macrophages. Subsequent studies revealed that cAMP-elevators blocked phosphorylation of p38 MAPK, but did not affect the activity of NF-kappaB binding to IL-12 promoter (-136/-112). This is the first report that cAMP elevators inhibit LPS-induced IL-12 production by a mechanism that is associated, at least in part, with p38-dependent inhibition by cAMP signaling pathways.

Novel multi-probe RNase protection assay set for detection of endotoxin associated receptors gene expression.

OBJECTIVE: To construct the multi-probe ribonuclease protection assay (RPA) template set to be used for detecting expression patterns of MD-2, TLR4, CD14 mRNAs in human peripheral blood mononuclear cells. METHODS: The designed cDNA fragments of the three genes were generated by polymerase chain reaction (PCR) using specific primers and directionally cloned into EcoR I and Hind III sites of expression plasmid pSP72 containing the T7 promoter, the linearized plasmids was used as template to synthesize anti-sense RNA probes. Then we extracted total RNA from peripheral blood mononuclear cells (PBMC) and detected the dynamic expression patterns of the three genes with RPA method. RESULTS: The proper sequence and orientation of the template set were confirmed by sequencing and the template set was successfully used to assay TLR4, MD-2 and CD14 mRNAs in human PBMC. The results showed that the three detected genes decreased transiently 1-3 hours after 100 ng/ml LPS stimulation. CONCLUSIONS: These new RPA multi-probe set provided valuable tool for the simultaneous quantitative determination of expression of TLR4, CD14 and MD-2 mRNAs in both constitutive and inducible types.

Intrathecal administration of triptolide, a T lymphocyte inhibitor, attenuates chronic constriction injury-induced neuropathic pain in rats.

Triptolide is a potent immunosuppressive drug capable of inhibiting T cell activation and proliferation. Recent studies show that T cells play an important role in neuropathic pain following nerve injury in rats. In this study, we investigated the effect of triptolide on T cell activation and development of neuropathic pain. Neuropathic pain by chronic constriction injury (CCI) was induced by loose ligation of the sciatic nerve in Sprague-Dawley rats. Triptolide (5 or 10 µg/kg) or vehicle (DMSO) was administered intrathecally after surgery for 7 days (n=8 per group). The right hind paw withdrawal threshold to von Frey filament stimuli and withdrawal latency to radiant heat were determined before and after the surgery (days 0 to 7). NF-κB activation and pro-inflammatory cytokine (TNF-α and IL-2) expression were determined by ELISA, Western blot, and real time-PCR. CCI of the sciatic nerve induced mechanical allodynia and thermal hyperalgesia in these rats. Intrathecal triptolide (5 and 10 µg/kg) suppressed the development of allodynia and thermal hyperalgesia. It also inhibited CCI-induced inflammation and T cell activation, by decreasing spinal cord TNF-α, IL-2 and NF-κB p65 levels. Motor dysfunction was not observed after triptolide treatment. In the present study, we demonstrated the suppressive effect of triptolide on the development of neuropathic pain. Therefore, triptolide could be a promising immunosuppressive agent in the treatment of neuropathic pain. Further studies are required to examine the safety of intrathecal triptolide for clinical application.

Follistatin-like 1 suppresses sensory afferent transmission by activating Na+,K+-ATPase.

Excitatory synaptic transmission is modulated by inhibitory neurotransmitters and neuromodulators. We found that the synaptic transmission of somatic sensory afferents can be rapidly regulated by a presynaptically secreted protein, follistatin-like 1 (FSTL1), which serves as a direct activator of Na(+),K(+)-ATPase (NKA). The FSTL1 protein is highly expressed in small-diameter neurons of the dorsal root ganglion (DRG). It is transported to axon terminals via small translucent vesicles and secreted in both spontaneous and depolarization-induced manners. Biochemical assays showed that FSTL1 binds to the α1 subunit of NKA and elevates NKA activity. Extracellular FSTL1 induced membrane hyperpolarization in cultured cells and inhibited afferent synaptic transmission in spinal cord slices by activating NKA. Genetic deletion of FSTL1 in small DRG neurons of mice resulted in enhanced afferent synaptic transmission and sensory hypersensitivity, which could be reduced by intrathecally applied FSTL1 protein. Thus, FSTL1-dependent activation of NKA regulates the threshold of somatic sensation.

[Effects of planting transgenic cotton on functional diversity of rhizosphere soil microbial community].

By the method of Biolog, a comparative study was made on the utilization level of single carbon source by the microbes in the rhizosphere soils of two transgenic cottons and their parents, aimed to approach the effects of planting transgenic cotton on the functional diversity of rhizosphere soil microbial community. Compared with planting non-transgenic cotton, planting transgenic cotton had less effects on the carbon sourceing utilization ability, Shannon functional diversity index, and evenness index of rhizosphere soil microbes at seedling, squaring, boll-opening, and senescence stages, but decreased the carbon source utilization ability and functional diversity index at flowering and boll-forming stage significantly. Principal component analysis (PCA) indicated that there existed greater differentiation in the carbon source utilization by the microbes in rhizosphere soils of nontransgenic and transgenic cottons at flowering and boll-forming stage, suggesting the significant difference in the carbon source utilization pattern of the microbes at this stage.