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1.
Dong-Xin Hu Qi-Feng Sun Lin Xu Hong-Da Lu Fan Zhang Zhen-Miao Li Ming-Yan Zhang 《World journal of gastroenterology : WJG》2022,28(4):464-478
BACKGROUND Esophageal squamous cell carcinoma(ESCC)is one of the most prevalent malignancies that seriously threaten people’s health worldwide.DEAD-box helicase 51(DDX51)is a member of the DEAD-box(DDX)RNA helicase family,and drives or inhibits tumor progression in multiple cancer types.AIM To determine whether DDX51 affects the biological behavior of ESCC.METHODS The expression of DDX51 in ESCC tumor tissues and adjacent normal tissues was detected by Immunohistochemistry(IHC)analyses and quantitative PCR(qPCR).We knocked down DDX51 in ESCC cell lines by using a small interfering RNA(siRNA)transfection.The proliferation,apoptosis,and mobility of DDX51 siRNAtransfected cells were detected.The effect of DDX51 on the phosphoinositide 3-kinase(PI3K)/AKT pathway was investigated by western blot analysis.A mouse xenograft model was established to investigate the effects of DDX51 knockdown on ESCC tumor growth.RESULTS DDX51 exhibited high expression in ESCC tissues compared with normal tissues and represented a poor prognosis in patients with ESCC.Knockdown of DDX51 induced inhibition of ESCC cell proliferation and promoted apoptosis.Moreover,DDX51 siRNA-expressing cells also exhibited lower migration and invasion rates.Investigations into the underlying mechanisms suggested that DDX51 knock down induced inactivation of the PI3K/AKT pathway,including decreased phosphorylation levels of phosphate and tensin homolog,PI3K,AKT,and mammalian target of rapamycin.Rescue experiments demonstrated that the AKT activator insulin-like growth factor 1 could reverse the inhibitory effects of DDX51 on ESCC malignant development.Finally,we injected DDX51 siRNA-transfected TE-1 cells into an animal model,which resulted in slower tumor growth.CONCLUSION Our study suggests for the first time that DDX51 promotes cancer cell proliferation by regulating the PI3K/AKT pathway;thus,DDX51 might be a therapeutic target for ESCC. 相似文献
2.
Orexins comprise two neuropeptides produced by orexin neurons in the lateral hypothalamus and are released by extensive projections of these neurons throughout the central nervous system. Orexins bind and activate their associated G protein-coupled orexin type 1 receptors(OX1Rs) and OX2Rs and act on numerous physiological processes, such as sleep-wake regulation, feeding, reward,emotion, and motivation. Research on the development of orexin receptor antagonists has dramatically increased with the approval of suvorexant for the treatment of primary insomnia. In the present review, we discuss recent findings on the involvement of the orexin system in the pathophysiology of psychiatric disorders, including sleep disorders,depression, anxiety, and drug addiction. We discuss the actions of orexin receptor antagonists, including selective OX1R antagonists (SORA1s), selective OX2R antagonists(SORA2s), and dual OX1/2R antagonists (DORAs), in the treatment of these disorders based on both preclinical and clinical evidence. SORA2s and DORAs have more pronounced efficacy in the treatment of sleep disorders,whereas SORA1s may be promising for the treatment of anxiety and drug addiction. We also discuss potential challenges and opportunities for the application of orexin receptor antagonists to clinical interventions. 相似文献
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Christiano Spindler Ethiane Segabinazi André Luís Ferreira de Meireles Francele Valente Piazza Filipe Mega Gabriela dos Santos Salvalaggio Matilde Achaval Viviane Rostirola Elsner Simone Marcuzzo 《中国神经再生研究》2019,(3)
It is widely known that maternal physical exercise is able to induce beneficial improvements in offspring cognition; however, the effects of paternal exercise have not been explored in detail. The present study was designed to evaluate the impact of paternal physical exercise on memory and learning, neuroplasticity and DNA methylation levels in the hippocampus of male offspring. Adult male Wistar rats were divided into two groups: sedentary or exercised fathers. The paternal preconception exercise protocol consisted of treadmill running, 20 minutes daily, 5 consecutive days per week for 22 days, while the mothers were not trained. After mating, paternal sperm was collected for global DNA methylation analysis. At postnatal day 53, the offspring were euthanized, and the hippocampus was dissected to measure cell survival by 5-bromo-2′-deoxiuridine and to determine the expression of synaptophysin, reelin, brain-derived neurotrophic factor and global DNA methylation levels. To measure spatial memory and learning changes in offspring, the Morris water maze paradigm was used. There was an improvement in spatial learning, as well as a significant decrease in hippocampal global DNA methylation levels in the offspring from exercised fathers compared with those from sedentary ones; however, no changes were observed in neuroplasticity biomarkers brain-derived neurotrophic factor, reelin and 5-bromo-2′-deoxiuridine. Finally, the global DNA methylation of paternal sperm was not significantly changed by physical exercise. These results suggest a link between paternal preconception physical activity and cognitive benefit, which may be associated with hippocampal epigenetic programming in male offspring. However, the biological mechanisms of this modulation remain unclear. 相似文献
5.
Ci Li Song-Yang Liu Meng Zhang Wei Pi Bo Wang Qi-Cheng Li Chang-Feng Lu Pei-Xun Zhang 《中国神经再生研究》2022,(9)
Exosomes derived from mesenchymal stem cells are of therapeutic interest because of their important role in intracellular communication and biological regulation.On the basis of previously studied nerve conduits,we designed a polydopamine-modified chitin conduit loaded with mesenchymal stem cell-derived exosomes that release the exosomes in a sustained and stable manner.In vitro experiments revealed that rat mesenchymal stem cell-derived exosomes enhanced Schwann cell proliferation and secretion of neurotrophic and growth factors,increased the expression of Jun and Sox2 genes,decreased the expression of Mbp and Krox20 genes in Schwann cells,and reprogrammed Schwann cells to a repair phenotype.Furthermore,mesenchymal stem cell-derived exosomes promoted neurite growth of dorsal root ganglia.The polydopamine-modified chitin conduits loaded with mesenchymal stem cell-derived exosomes were used to bridge 2 mm rat sciatic nerve defects.Sustained release of exosomes greatly accelerated nerve healing and improved nerve function.These findings confirm that sustained release of mesenchymal stem cell-derived exosomes loaded into polydopamine-modified chitin conduits promotes the functional recovery of injured peripheral nerves. 相似文献
6.
Oxidized low-density lipoprotein receptor 1(OLR1)is upregulated in neurons and participates in hypertension-induced neuronal apoptosis.OLR1 deletion exerts protective effects on cerebral damage induced by hypertensive-induced stroke.Therefore,OLR1 is likely involved in the progress of intracerebral hemorrhage.In this study,we examined the potential role of OLR1 in intracerebral hemorrhage using a rat model.OLR1 small interfering RNA(10μL;50 pmol/μL)was injected into the right basal ganglia to knock down OLR1.Twenty-four hours later,0.5 U collagenase type VII was injected to induce intracerebral hemorrhage.We found that knockdown of OLR1 attenuated neurological behavior impairment in rats with intracerebral hemorrhage and reduced hematoma,neuron loss,inflammatory reaction,and oxidative stress in rat brain tissue.We also found that silencing of OLR1 suppressed ferroptosis induced by intracerebral hemorrhage and the p38 signaling pathway.Therefore,silencing OLR1 exhibits protective effects against secondary injury of intracerebral hemorrhage.These findings suggest that OLR1 may be a novel potential therapeutic target for intracerebral hemorrhage. 相似文献
7.
Li-Mei Wang Xiao-Meng Chen Hai-Jing Yan Shu Yan Xiao-Yan Sun Da-Wei Zhang Hua Yang Dan-Li Lu Cheng-Ye Che 《国际眼科》2022,15(4):541-546
AIM: To investigate whether non-canonical autophagy transport receptor cell cycle progression 1 (CCPG1) is involved in the corneal antifungal immune response.
METHODS: Human corneal epithelial cells (HCECs) and human myeloid leukemia mononuclear cells (THP-1) macrophages stimulated by Aspergillus fumigatus (A. fumigatus) were used as cell models. The expression of CCPG1 mRNA was detected by qRT-PCR. Western blot was used to determine the protein expression of CCPG1 and interleukin-1β (IL-1β). The dectin-1 neutralizing antibody was used to detect the association between dectin-1 and CCPG1. Immunofluorescence was used to observe the colocalization of CCPG1 and C-type lectin-like receptor-1 (CLEC-1) in THP-1 macrophages.
RESULTS: The expression of CCPG1 started to increase at 4h after infection and increased in a time-dependent manner in HCECs and THP-1 macrophages. With dectin-1 neutralizing antibody pretreatment, the expression of IL-1β was down-regulated. CCPG1 up-regulation in response to A. fumigatus infection was independent of dectin-1. Immunofluorescence showed the colocalization of CCPG1 and CLEC-1 in THP-1 macrophages.
CONCLUSION: As a specific autophagy protein of non-canonical autophagy pathway, CCPG1 is involved in corneal infection with A. fumigatus. 相似文献
8.
Zhuo Shi Xiao-Fei Li Ya-Lei Liu Peng-Yan Li Ming Niu Zhao-Fang Bai Guang-Qin Zhang Yang Lu Jia-Bo Wang 《World Journal of Traditional Chinese Medicine》2021,(2)
Objective: Polygoni Multiflori Radix (PM) is a traditional herbal medicine with repeated reports of liver injury events in recent years. We wondered whether the classical processing method, namely, nine-time steaming and sun drying (NSSD), had toxicity-attenuating effects on PM and the relationships between toxicity and times of processing, as well as with the alteration trends of its compounds. Materials and Methods: The chemical fingerprints of different PM extracts were developed using ultra-high-performance liquid chromatography. The spectrum-toxicity correlation between the chemical fingerprints and hepatocellular toxicity was analyzed with multiple correlation analysis. Results: The results suggested that the hepatotoxicity of NSSD processing products markedly decreased with the repeated steaming and sun drying, which was obviously superior to the product processed by the modern method. Comprehensive analysis revealed that the contents of cis-stilbene glycoside and emodin-8-O-β-D-glucoside related to liver injury susceptibility were reduced with the times of NSSD processing, which was consistent with the decreased trend of hepatocellular toxicity. After the five times of NSSD, the contents of them as well as the hepatotoxicity of PM were steady. Moreover, we found that the contents of catechin and physcion declined rapidly after the one time of NSSD and then remained stable until the nine times of NSSD. Based on the fact, they could be utilized to indicate whether PM products were processed by steaming and sun drying. Conclusions: This paper confirmed that the NSSD had a good influence on the toxicity attenuating to PM and found four compounds which could apply for the quality control of PM. 相似文献
9.
Hong-Yu Jia Feng Ding Jian-Yang Chen Jiang-Shan Lian Yi-Min Zhang Lin-Yan Zeng Dai-Rong Xiang Liang Yu Jian-Hua Hu Guo-Dong Yu Huan Cai Ying-Feng Lu Lin Zheng Lan-Juan Li Yi-Da Yang 《World journal of gastroenterology : WJG》2015,21(12):3657-3662
AIM: To evaluate urine β2-microglobulin(β2-M), retinol-binding protein(RBP) excretion, and renal impairment with adefovir dipivoxil(ADV) for chronic hepatitis B. METHODS: We enrolled 165 patients with chronic hepatitis B infection who were treated with ADV monotherapy(n = 90) or ADV plus lamivudine combination therapy(n = 75). An additional 165 chronic hepatitis B patients treated with entecavir were recruited as controls. We detected serum creatinine, urine β2-M, and RBP levels, and estimated the glomerular filtration rate(e GFR) at the initiation of antiviral therapy and every 6 mo for a period of five years. RESULTS: Urine β2-M abnormalities were observed in patients during the first(n = 3), second(n = 7), third(n = 11), fourth(n = 16), and fifth(n = 21) year of ADV treatment. Urinary RBP abnormalities were observed in patients during the first(n = 2), second(n = 8), third(n = 12), fourth(n = 15), and fifth(n = 22) year of ADV treatment. e GFR decreased 20%-30% from baseline in 20 patients, 30%-50% in 12 patients, and > 50% in 3 patients during the five years of treatment. Further analysis indicated that decreases in e GFR of ≥ 30% relative to the baseline level correlated significantly with urine RBP and β2-M abnormalities. In contrast, both serum creatinine and e GFR remained stable in patients treated with entecavir, and only one of these patients developed a urine β2-M abnormality, and two developed urine RBP abnormalities during the five years of treatment. CONCLUSION: Urine RBP and β2-M are biomarkers of renal injury during long-term ADV treatment for chronic hepatitis B, and indicate when treatment should be switched to entecavir. 相似文献
10.