Defective synaptic plasticity in a model of Coffin-Lowry syndrome is rescued by simultaneously targeting PKA and MAPK pathways.

Empirical and computational methods were combined to examine whether individual or dual-drug treatments can restore the deficit in long-term synaptic facilitation (LTF) of the Aplysia sensorimotor synapse observed in a cellular model of Coffin-Lowry syndrome (CLS). The model was produced by pharmacological inhibition of p90 ribosomal S6 kinase (RSK) activity. In this model, coapplication of an activator of the mitogen-activated protein kinase (MAPK) isoform ERK and an activator of protein kinase A (PKA) resulted in enhanced phosphorylation of RSK and enhanced LTF to a greater extent than either drug alone and also greater than their additive effects, which is termed synergism. The extent of synergism appeared to depend on another MAPK isoform, p38 MAPK. Inhibition of p38 MAPK facilitated serotonin (5-HT)-induced RSK phosphorylation, indicating that p38 MAPK inhibits activation of RSK. Inhibition of p38 MAPK combined with activation of PKA synergistically activated both ERK and RSK. Our results suggest that cellular models of disorders that affect synaptic plasticity and learning, such as CLS, may constitute a useful strategy to identify candidate drug combinations, and that combining computational models with empirical tests of model predictions can help explain synergism of drug combinations.

Melatonin enhances autophagy and decreases apoptosis induced by nanosilica in RAW264.7 cells.

Melatonin is one of the main hormones that regulate biological rhythms and have immunomodulation, anti-inflammatory, and antioxidation functions. In this study, we aimed to explore the effect of melatonin on the autophagy, apoptosis, and inflammatory reaction of macrophages (RAW264.7 cells) stimulated by nanosilica. SiO2 (100 mg/mL, 10-20 nm) was used to stimulate RAW264.7 cells at different time points (0, 2, 4, 8, 12, and 24 hr). Melatonin (200 µM) was added to SiO2 -stimulated macrophages at 12 hr. Beclin-1, LC3, Bax, Bcl-2, and Caspase-3 were examined with western blotting. Flow cytometry was used to detect apoptosis. The levels of TNF-α, IL-1ß, and IL-18 were detected by ELISA. The level of TNF-α in the supernatant of SiO2 -stimulated cells gradually increased with time but decreased following melatonin administration. In contrast, the expression of IL-1ß and IL-18 increased after melatonin treatment. LC3 and Bax signaling pathways were activated in SiO2 -stimulated RAW264.7 cells, showing elevated expression of LC3 and reduced expression of Bax in the melatonin-treated cells. GFP-LC3 puncta were significantly increased in SiO2 -stimulated RAW264.7 cells and decreased in melatonin-treated cells. The apoptotic rate in SiO2 -stimulated RAW264.7 cells increased with time and decreased after melatonin treatment, and the number of phagosomes increased with the stimulation of nanosilica and the treatment of melatonin. Melatonin might promote autophagy and inhibit apoptosis as well as inflammatory responses of RAW264.7 cells stimulated by nanosilica. © 2019 IUBMB Life, 2019.

Identification of a multidimensional transcriptome prognostic signature for lung adenocarcinoma.

BACKGROUND: Lung adenocarcinoma (LUAD) is one of the leading contributors to cancer-related deaths worldwide. The objective of the current study is to identify a multidimensional transcriptome prognostic signature by combining protein-coding gene (PCG) with long non-coding RNA (lncRNA) for patients with LUAD. METHODS: We obtained LUAD PCG and lncRNA expression profile data from three datasets in the Gene Expression Omnibus database and conducted survival analyzes for these individuals. RESULTS: We established a predictive model comprising the three PCGs (NHLRC2, PLIN5, GNAI3), and one lncRNA (AC087521.1). This model segregated patients with LUAD into low- and high-risk groups based on significant differences in survival in the training dataset (GSE31210, n = 226, log-rank test P < .001). Risk stratification of the model was subsequently validated in other two test datasets (GSE37745, n = 106, log-rank test P < .001; GSE30219, n = 85, log-rank test P = .006). Time-dependent receiver operating characteristic (timeROC) curve analysis demonstrated that the model correlated strongly with disease progression and outperformed pathological stage in terms of prognostic ability. Cox proportional hazards regression analysis revealed that the signature could serve as an independent predictor of clinical outcomes in patients with LUAD. CONCLUSIONS: We describe a novel multidimensional transcriptome signature that can predict survival probabilities in patients with LUAD.

Superior long-term synaptic memory induced by combining dual pharmacological activation of PKA and ERK with an enhanced training protocol.

Developing treatment strategies to enhance memory is an important goal of neuroscience research. Activation of multiple biochemical signaling cascades, such as the protein kinase A (PKA) and extracellular signal-regulated kinase (ERK) pathways, is necessary to induce long-term synaptic facilitation (LTF), a correlate of long-term memory (LTM). Previously, a computational model was developed which correctly predicted a novel enhanced training protocol that augmented LTF by searching for the protocol with maximal overlap of PKA and ERK activation. The present study focused on pharmacological approaches to enhance LTF. Combining an ERK activator, NSC, and a PKA activator, rolipram, enhanced LTF to a greater extent than did either drug alone. An even greater increase in LTF occurred when rolipram and NSC were combined with the Enhanced protocol. These results indicate superior memory can be achieved by enhanced protocols that take advantage of the structure and dynamics of the biochemical cascades underlying memory formation, used in conjunction with combinatorial pharmacology.

Diagnostic Values of sVEGFR-1 and Endostatin in Malignant Pleural Effusions in Patients with Lung Cancer.

BACKGROUND: The diagnosis of malignant pleural effusion (MPE) remains a common clinical challenge because of the sensitivity of conventional cytology for the detection is insufficient. Thus, a sensitive clinical marker for diagnosis is required. The aim of this study was to assess the role of two anti-angiogenic cytokines, soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) and endostatin, in diagnosing MPE. METHODS: Effusion samples from 44 patients with MPE caused by lung cancer and from 36 patients with benign pleural effusion (BPE) were collected. The concentrations of sVEGFR-1 and endostatin in pleural fluid were determined by an enzyme-linked immunosorbent assay (ELISA). The diagnostic performance was measured by receiver operating characteristic curves (ROCs). RESULTS: The levels of sVEGFR-1 and endostatin in MPE due to lung cancer were significantly higher than those in BPE (p < 0.05). The sensitivity and specificity of endostatin were 52.27% and 86.11%, respectively, while for sVEGFR-1, the sensitivity was 88.64% and the specificity was 58.33%. Interestingly, the combination of sVEGFR1 and endostatin produced better sensitivity and specificity of 72.73% and 83.33%, respectively. In addition, the levels of sVEGFR-1 and endostatin were significantly related to each other (p < 0.05), and the levels of endostatin in bloody effusions were significantly higher than those in non-bloody effusions (p < 0.05). CONCLUSIONS: Our study indicated that the levels of sVEGFR-1 and endostatin were significantly elevated in MPE. The combined detection of sVEGFR-1 and endostatin may be useful in the diagnosis of MPE.

Rescue of impaired long-term facilitation at sensorimotor synapses of Aplysia following siRNA knockdown of CREB1.

Memory impairment is often associated with disrupted regulation of gene induction. For example, deficits in cAMP response element-binding protein (CREB) binding protein (CBP; an essential cofactor for activation of transcription by CREB) impair long-term synaptic plasticity and memory. Previously, we showed that small interfering RNA (siRNA)-induced knockdown of CBP in individual sensory neurons significantly reduced levels of CBP and impaired 5-HT-induced long-term facilitation (LTF) in sensorimotor cocultures from Aplysia. Moreover, computational simulations of the biochemical cascades underlying LTF successfully predicted training protocols that restored LTF following CBP knockdown. We examined whether simulations could also predict a training protocol that restores LTF impaired by siRNA-induced knockdown of the transcription factor CREB1. Simulations based on a previously described model predicted rescue protocols that were specific to CREB1 knockdown. Empirical studies demonstrated that one of these rescue protocols partially restored impaired LTF. In addition, the effectiveness of the rescue protocol was enhanced by pretreatment with rolipram, a selective cAMP phosphodiesterase inhibitor. These results provide further evidence that computational methods can help rescue disruptions in signaling cascades underlying memory formation. Moreover, the study demonstrates that the effectiveness of computationally designed training protocols can be enhanced with complementary pharmacological approaches.

MiR-541-3p reverses cancer progression by directly targeting TGIF2 in non-small cell lung cancer.

Lung cancer remains a leading cause of cancer-associated mortality worldwide, and non-small lung cancer (NSCLC) is responsible for over 80 % of lung cancer-related deaths. Identifying novel molecular biomarker that can inhibit the progression of lung cancer will facilitate the development of new treatment strategies. Herein, we demonstrated that miR-541-3p is a tumor-suppressor microRNA (miRNA) in NSCLC progression. We found that expression of miR-541-3p was decreased obviously in NSCLC tissues and plasma. Down-regulation of miR-541-3p was associated with TNM stage and postoperative survival. Overexpression of miR-541-3p inhibited the growth and metastasis of NSCLC cells. The TGIF2 was a direct target of miR-541-3p and promoted the growth and metastasis of NSCLC cells. Further study showed that TGIF2 could reverse the inhibitory effect of miR-541-3p on growth and metastasis of NSCLC cells. Taken together, our data highlight the pivotal role of miR-541-3p in the progression of NSCLC. Thus, miR-541-3p may be a potential prognostic marker and of treatment relevance for NSCLC progression intervention.

JNK-TLR9 signal pathway mediates allergic airway inflammation through suppressing melatonin biosynthesis.

Toll-like receptors (TLRs) play pivotal role in the pathogenesis of allergic airway diseases such as asthma. TLR9 is one of the most extensively studied TLRs as an approach to treat asthma. In this study, we investigated the role of TLR9 in the allergic airway inflammation and the underlying mechanism. Wild-type (WT) mice and TLR9(-/-) mice were sensitized and challenged with OVA to establish allergic airway disease model. We found that the expression of TLR9 was elevated concomitantly with airway inflammation post-OVA challenge, and TLR9 deficiency effectively inhibited airway inflammation, including serum OVA-specific immunoglobulin E (IgE), pulmonary inflammatory cell recruitment, mucus secretion, and bronchoalveolar lavage fluid (BALF) inflammatory cytokine production. Meanwhile, the protein expression of hydroxyindole-o-methyltransferase (HIOMT) in lung tissues, the level of melatonin in serum, and BALF were reduced in OVA-challenged WT mice, while these reductions were significantly restored by TLR9 deficiency. Additionally, we showed that although TLR9 deficiency had no effect on OVA-induced phosphorylation of JNK, inhibition of JNK by specific inhibitor SP600125 significantly decreased OVA-induced expression of TLR9, suggesting that JNK is the upstream signal molecular of TLR9. Furthermore, SP600125 treatment promoted resolution of allergic airway inflammation in OVA-challenged WT mice, but not further ameliorated allergic airway inflammation in OVA-challenged TLR9(-/-) mice. Similarly, SP600125 significantly restored the protein expression of HIOMT and the level of melatonin in OVA-challenged WT mice, while such effect was not further enhanced by TLR9 deficiency. Collectively, our results indicated that JNK-TLR9 signal pathway mediates allergic airway inflammation through suppressing melatonin biosynthesis.

Associations of pulmonary function with serum biomarkers and dialysis adequacy in patients undergoing peritoneal dialysis.

BACKGROUND: As lung impairment is an indicator of increased morbidity and mortality in patients receiving continuous ambulatory peritoneal dialysis (CAPD), the risk factors associated with impaired lung function are of great significance. The aim of this study is to elucidate the effects of inflammatory biomarkers and dialysis adequacy on pulmonary function, in CAPD patients. METHODS: 101 patients undergoing CAPD, 30 CKD5 patients and 30 healthy subjects were enrolled. Spirometry and serum biomarkers were evaluated in each subject. Pulmonary function was compared among patients and control groups. Pearson analysis was used to analyze the correlation between serum biomarkers, dialysis adequacy and pulmonary function. RESULTS: Lower vital capacity, maximal voluntary ventilation (MVV), forced vital capacity (FVC), peak expiratory flow (PEF), maximal mid-expiratory flow rate (MMEF), and diffusing capacity of the lung for carbon monoxide (DLCO) were observed in the CAPD group (all P < 0.05) when compared with control subjects. DLCO % was negatively correlated with CRP (r = -0.349, P = 0.007) and positively correlated with albumin (r = 0.401, P = 0.002). Total Kt/V was associated positively with MMEF % (r = 0.316, P = 0.019), and MVV % (r = 0.362, P = 0.007). nPNA was positively correlated with FVC % (r = 0.295, P = 0.049) and MMEF % (r = 0.381, P = 0.010). CONCLUSION: The results suggest that lung function decline was directly related to higher CRP level, hypoalbuminemia, and dialysis inadequacy. These findings provide the evidence that inflammation and dialysis adequacy play a role in predicting outcomes of CAPD patients with pulmonary impairment.

Gemcitabine-Induced Autophagy Protects Human Lung Cancer Cells from Apoptotic Death.

PURPOSE: Gemcitabine has been used as a therapeutic drug combined with cisplatin for the treatment of lung cancer patients. However, the prognosis is poor due to acquired resistance. Accumulating studies have revealed that autophagy may contribute to the drug resistance. Therefore, the present study is aimed to clarify the mechanisms underlying gemcitabine-acquired resistance. METHODS: SPC-A1 and A549 cells were incubated with gemcitabine followed by assessment of cell viability with MTT assays. GFP-LC3 transient transfection, MDC staining, and transmission electron microscopy were used to detect the change of autophagy at morphological level. Flow cytometry was used to monitor the effect of 3-MA on gemcitabine-induced apoptosis. Western blot analysis was used to detect the expression of p62, LC3, Beclin-1, ATG5, activated caspase 3, Bax, BNIP3, BNIP3L, and Bcl-2. RESULTS: Our study showed that gemcitabine significantly induced both autophagy and apoptosis in human lung cancer cells SPC-A1 and A549. Of interest was that when autophagy was inhibited by 3-MA, the gemcitabine-induced apoptosis was effectively enhanced, suggesting that gemcitabine can activate autophagy to impair the chemosensitivity of lung cancer cells. Furthermore, the inhibition of autophagy by 3-MA further increased the expression of activated caspase 3, Bax, BNIP3, and BNIP3L, all are critical apoptotic mediators. Contrarily, 3-MA treatment further decreased the expression of Bcl-2, which is an important anti-apoptotic protein. CONCLUSION: Our study indicated that autophagy protected human lung cancer cells from gemcitabine-induced apoptosis, and the combined use of gemcitabine and an autophagic inhibitor in lung cancer patients may be an effective therapeutic strategy.

Doxorubicin attenuates serotonin-induced long-term synaptic facilitation by phosphorylation of p38 mitogen-activated protein kinase.

Doxorubicin (DOX) is an anthracycline used widely for cancer chemotherapy. Its primary mode of action appears to be topoisomerase II inhibition, DNA cleavage, and free radical generation. However, in non-neuronal cells, DOX also inhibits the expression of dual-specificity phosphatases (also referred to as MAPK phosphatases) and thereby inhibits the dephosphorylation of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (p38 MAPK), two MAPK isoforms important for long-term memory (LTM) formation. Activation of these kinases by DOX in neurons, if present, could have secondary effects on cognitive functions, such as learning and memory. The present study used cultures of rat cortical neurons and sensory neurons (SNs) of Aplysia to examine the effects of DOX on levels of phosphorylated ERK (pERK) and phosphorylated p38 (p-p38) MAPK. In addition, Aplysia neurons were used to examine the effects of DOX on long-term enhanced excitability, long-term synaptic facilitation (LTF), and long-term synaptic depression (LTD). DOX treatment led to elevated levels of pERK and p-p38 MAPK in SNs and cortical neurons. In addition, it increased phosphorylation of the downstream transcriptional repressor cAMP response element-binding protein 2 in SNs. DOX treatment blocked serotonin-induced LTF and enhanced LTD induced by the neuropeptide Phe-Met-Arg-Phe-NH2. The block of LTF appeared to be attributable to overriding inhibitory effects of p-p38 MAPK, because LTF was rescued in the presence of an inhibitor (SB203580 [4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)-1H-imidazole]) of p38 MAPK. These results suggest that acute application of DOX might impair the formation of LTM via the p38 MAPK pathway.

Repeated inhalation of sevoflurane inhibits airway inflammation in an OVA-induced mouse model of allergic airway inflammation.

BACKGROUND AND OBJECTIVE: Repeated inhalation of sevoflurane (SVF) can benefit asthmatic patients by bronchodilation. However, the impact of repeated inhalation of SVF on allergic airway inflammation has not been clarified. This study was aimed at investigating the effects of repeated inhalation of SVF on airway inflammation in mice. METHODS: Female C57BL/6 mice were sensitized with ovalbumin (OVA) and treated by inhalation with SVF or vehicle daily for seven consecutive days, immediately followed by OVA challenge. Airway inflammation was evaluated by counting the numbers of different types of inflammatory infiltrates in bronchoalveolar lavage fluid (BALF), histology, cytokine measurements and mucus production in individual mice. RESULTS: In comparison with the OVA group, repeated inhalation of SVF significantly reduced the numbers of total cells, eosinophils, lymphocytes, macrophages and neutrophils (P < 0.05 to P < 0.01), and the levels of BALF tumour necrosis factor-α and lung high-mobility group box 1 (P < 0.01), accompanied by elevated levels of BALF interleukin-10 in allergic mice (P < 0.05). Repeat inhalation of SVF decreased the levels of serum OVA-specific immunoglobulin E (IgE) and mitigated allergic airway epithelial goblet cell hyperplasia and mucus hypersecretion in allergic mice (P < 0.01). CONCLUSIONS: Repeated inhalation of SVF inhibits allergic airway inflammation by reducing inflammatory infiltrates, improving the imbalance of cytokine responses and mitigating allergen-specific IgE responses and goblet cell hyperplasia in mice.

Invasive pulmonary aspergillosis accompanied by soft tissue lesions during treatment of a patient with hyperthyroidism: a case report.

Invasive pulmonary aspergillosis (IPA) is difficult to diagnose because it requires histopathology and tissue culture, as well as due to its rapid progression. Invasive pulmonary aspergillosis is the primary cause of pulmonary mycosis in China, which can occur in patients with neutrophil deficiency, leukaemia or lymphoma, malignant tumours, or chronic obstructive pulmonary disease with long-term corticosteroid use or bacterial exacerbations. Such fungal infections can lead to disseminated disease and death within weeks, and the mortality rate for untreated invasive aspergillosis is high. Therefore, increased awareness of invasive aspergillosis in non-traditional hosts is warranted due to the high mortality rate experienced by patients with this disease. Invasive pulmonary aspergillosis has become a principal cause of life-threatening infections in immunocompromised patients. Invasive aspergillosis frequently involves the lung parenchyma and is infrequently accompanied by soft tissue lesions. We present an unusual case of a patient with agranulocytosis that was caused by methimazole that was given to control his hyperthyroidism, and IPA that was accompanied by unusual maxillofacial soft tissue swelling that required treatment with voriconazole. Upon follow-up 11 months later, a chest computed tomography scan (CT) revealed that most lesions had been completely absorbed. Moreover, his maxillofacial ulcers had become encrusted, and the soft tissue swelling had subsided.

Deficit in long-term synaptic plasticity is rescued by a computationally predicted stimulus protocol.

Mutations in the gene encoding CREB-binding protein (CBP) cause deficits in long-term plasticity, learning, and memory. Here, long-term synaptic facilitation (LTF) at Aplysia sensorimotor synapses in cell culture was used as a model system to investigate methods for overcoming deficits in LTF produced by a CBP knockdown. Injecting CBP-siRNA into individual sensory neurons reduced CBP levels and impaired LTF produced by a standard protocol of five 5-min pulses of serotonin (5-HT) delivered at 20 min interstimulus intervals. A computational model, which simulated molecular processes underlying LTF induction, predicted a rescue protocol of five pulses of 5-HT at non-uniform interstimulus intervals that overcame the consequences of reduced CBP and restored LTF. These results suggest that complementary empirical and computational studies can identify methods for ameliorating impairments of learning attributable to molecular lesions.

Increased cysteinyl-tRNA synthetase drives neuroinflammation in Alzheimer's disease.

BACKGROUND: Microglia-mediated neuroinflammation in Alzheimer's disease (AD) is not only a response to pathophysiological events, but also plays a causative role in neurodegeneration. Cytoplasmic cysteinyl-tRNA synthetase (CARS) is considered to be a stimulant for immune responses to diseases; however, it remains unknown whether CARS is involved in the pathogenesis of AD. METHODS: Postmortem human temporal cortical tissues at different Braak stages and AD patient-derived serum samples were used to investigate the changes of CARS levels in AD by immunocytochemical staining, real-time PCR, western blotting and ELISA. After that, C57BL/6J and APP/PS1 transgenic mice and BV-2 cell line were used to explore the role of CARS protein in memory and neuroinflammation, as well as the underlying mechanisms. Finally, the associations of morphological features among CARS protein, microglia and dense-core plaques were examined by immunocytochemical staining. RESULTS: A positive correlation was found between aging and the intensity of CARS immunoreactivity in the temporal cortex. Both protein and mRNA levels of CARS were increased in the temporal cortex of AD patients. Immunocytochemical staining revealed increased CARS immunoreactivity in neurons of the temporal cortex in AD patients. Moreover, overexpression of CARS in hippocampal neurons induced and aggravated cognitive dysfunction in C57BL/6J and APP/PS1 mice, respectively, accompanied by activation of microglia and the TLR2/MyD88 signaling pathway as well as upregulation of proinflammatory cytokines. In vitro experiments showed that CARS treatment facilitated the production of proinflammatory cytokines and the activation of the TLR2/MyD88 signaling pathway of BV-2 cells. The accumulation of CARS protein occurred within dense-core Aß plaques accompanied by recruitment of ameboid microglia. Significant upregulation of TLR2/MyD88 proteins was also observed in the temporal cortex of AD. CONCLUSIONS: The findings suggest that the neuronal CARS drives neuroinflammation and induces memory deficits, which might be involved in the pathogenesis of AD.

Dynamics and Mechanisms of ERK Activation after Different Protocols that Induce Long-Term Synaptic Facilitation in Aplysia.

Phosphorylation of the MAPK family member extracellular signal-regulated kinase (ERK) is required to induce long-term synaptic plasticity, but little is known about its persistence. We examined ERK activation by three protocols that induce long-term synaptic facilitation (LTF) of the Aplysia sensorimotor synapse - the standard protocol (five 5-min pulses of 5-HT with interstimulus intervals (ISIs) of 20 min), the enhanced protocol (five pulses with irregular ISIs, which induces greater and longer-lasting LTF) and the two-pulse protocol (two pulses with ISI 45 min). Immunofluorescence revealed complex ERK activation. The standard and two-pulse protocols immediately increased active, phosphorylated ERK (pERK), which decayed within 5 h. A second wave of increased pERK was detected 18 h post-treatment for all protocols. This late phase was blocked by inhibitors of protein kinase A, TrkB and TGF-ß. These results suggest that complex interactions among kinase pathways and growth factors contribute to the late increase of pERK. ERK activity returned to basal 24 h after the standard or two-pulse protocols, but remained elevated 24 h for the enhanced protocol. This 24-h elevation was also dependent on PKA and TGF-ß, and partly on TrkB. These results begin to characterize long-lasting ERK activation, plausibly maintained by positive feedback involving growth factors and PKA, that appears essential to maintain LTF and LTM. Because many processes involved in LTF and late LTP are conserved among Aplysia and mammals, these findings highlight the importance of examining the dynamics of kinase cascades involved in vertebrate long-term memory.

The requirement for enhanced CREB1 expression in consolidation of long-term synaptic facilitation and long-term excitability in sensory neurons of Aplysia.

Accumulating evidence suggests that the transcriptional activator cAMP response element-binding protein 1 (CREB1) is important for serotonin (5-HT)-induced long-term facilitation (LTF) of the sensorimotor synapse in Aplysia. Moreover, creb1 is among the genes activated by CREB1, suggesting a role for this protein beyond the induction phase of LTF. The time course of the requirement for CREB1 synthesis in the consolidation of long-term facilitation was examined using RNA interference techniques in sensorimotor cocultures. Injection of CREB1 small-interfering RNA (siRNA) immediately or 10 h after 5-HT treatment blocked LTF when measured at 24 and 48 h after treatment. In contrast, CREB1 siRNA did not block LTF when injected 16 h after 5-HT treatment. These results demonstrate that creb1 expression must be sustained for a relatively long time to support the consolidation of LTF. In addition, LTF is also accompanied by a long-term increase in the excitability (LTE) of sensory neurons (SNs). Because LTE was observed in the isolated SN after 5-HT treatment, this long-term change was intrinsic to that element of the circuit. LTE was blocked when CREB1 siRNA was injected into isolated SNs immediately after 5-HT treatment. These data suggest that 5-HT-induced CREB1 synthesis is required for consolidation of both LTF and LTE.

Serotonin-mediated synapsin expression is necessary for long-term facilitation of the Aplysia sensorimotor synapse.

Serotonin (5-HT)-induced long-term facilitation (LTF) of the Aplysia sensorimotor synapse depends on enhanced gene expression and protein synthesis, but identification of the genes whose expression and regulation are necessary for LTF remains incomplete. In this study, we found that one such gene is synapsin, which encodes a synaptic vesicle-associated protein known to regulate short-term synaptic plasticity. Both synapsin mRNA and protein levels were increased by 5-HT. Upregulation of synapsin protein occurred in presynaptic sensory neurons at neurotransmitter release sites. To investigate the molecular mechanisms underlying synapsin regulation, we cloned the promoter region of Aplysia synapsin, and found that the synapsin promoter contained a cAMP response element (CRE), raising the possibility that the transcriptional activator CRE-binding protein 1 (CREB1) mediates 5-HT-induced regulation of synapsin. Indeed, binding of CREB1 to the synapsin promoter was increased following treatment with 5-HT. Furthermore, increased acetylation of histones H3 and H4 and decreased association of histone deacetylase 5 near the CRE site are consistent with transcriptional activation by CREB1. RNA interference (RNAi) targeting synapsin mRNA blocked the 5-HT-induced increase in synapsin protein levels and LTF; in the absence of 5-HT treatment, basal synapsin levels were unaffected. These results indicate that the 5-HT-induced regulation of synapsin levels is necessary for LTF and that this regulation is part of the cascade of synaptic events involved in the consolidation of memory.

Decreased expression of Beclin-1 and LC3 in human lung cancer.

Autophagy, a conversed response to stress, has recently been studied in human cancers. Two important autophagic genes-Beclin-1 and LC3 are reported in several human cancers. However, the expressions of Beclin-1 and LC3 in lung cancer have not yet been investigated. In the present study, we investigated the expression of Beclin-1 and LC3, and the relationship between the expression profile and the clinical or pathological changes in human lung cancer. 40 primary lung cancer patients are involved in present study. mRNA expressions of Beclin-1 and LC3-II were detected by Real Time PCR and the protein levels were assessed by immunohistochemistry and western blot. Relative lower expressions of Beclin-1 and LC3-II mRNA were found in the lung cancer tissues compared to counterpart normal tissues. Consistently, the lower amount of Beclin-1 and LC3-II protein was found in lung cancer tissues. However, the expressions of Beclin-1 and LC3-II in lung cancer tissues were not affected by patients' age, gender, smoking, histological type, lymph node metastasis and tumor-node-metastasis (TNM) stage. Both mRNA and protein levels of Beclin-1 and LC3-II were significantly decreased in lung cancer tissues which suggested that autophagy may be involved in the pathogenesis of lung cancer.

Serotonin- and training-induced dynamic regulation of CREB2 in Aplysia.

Long-term memory and plasticity, including long-term synaptic facilitation (LTF) of the Aplysia sensorimotor synapse, depend on the activation of transcription factors that regulate genes necessary for synaptic plasticity. In the present study we found that treatment with 5-HT and behavioral training produce biphasic changes in the expression of CREB2, a transcriptional repressor. An immediate increase in CREB2 protein was followed by a subsequent decrease. The effects of these treatments persist for at least 24 h and are observed in isolated sensory neurons. This study suggests that the dynamics of CREB2 expression could contribute to the consolidation of memory.