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81.
Nephrolithiasis is a common disease of the urinary system, of which idiopathic calcium oxalate (CaOx) kidney stones, in particular, are one of the special types. In the initial stages of CaOx kidney stone formation, Randall's plaques (RPs) develop. Liver X receptors (LXRs) inhibit oxidative stress and inflammatory in other diseases; nevertheless, the role of LXRs in nephrolithiasis has yet to be elucidated. In this study, the role of LXRs in the progression of RP formation was investigated. Microarray analysis revealed that LXR/RXR levels were significantly greater in low-plaque tissues (<5%) than in high-plaque tissues (>5%), confirming the link between LXR activation and RP formation. Correspondingly, expression levels of two LXR target genes, LXRα and LXRβ, were lower in high-plaque tissues than in low-plaque tissues. In vitro, LXR agonist alleviated calcium oxalate monohydrate-induced cellular calcium deposits and apoptosis. LXR activation decreased reactive oxygen species production and gene expression of inflammatory mediators, including osteopontin that has recently been demonstrated to correlate with the development of RPs. Moreover, p38 MAPK and JNK signaling may mediate LXR-regulated expression in HK-2 cells. In an animal model, the deposition was reduced by activating LXR, and osteopontin expression was also inhibited. Our findings suggest a role for LXRs in the progression of idiopathic CaOx kidney stones; LXR agonists may have therapeutic potential for the treatment of nephrolithiasis.  相似文献   
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Tian  Peng  Liu  Shengen  Wang  Qingkui  Sun  Tao  Blagodatskaya  Evgenia 《Plant and Soil》2019,437(1-2):439-454
Plant and Soil - Understanding seed-soil dynamics is important for improving plant emergence and growth. The objectives of this study were to develop a Seed-Soil model to simulate the dynamic...  相似文献   
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Wang  Xuhui  Wang  Hong  Zhang  Tao  He  Meng  Liang  Hong  Wang  Hao  Xu  Lunshan  Chen  Sha  Xu  Minhui 《Neurochemical research》2019,44(7):1690-1702

Trigeminal neuralgia (TN) is a type of chronic neuropathic pain that is caused by peripheral nerve lesions that result from various conditions, including the compression of vessels, tumors and viral infections. MicroRNAs (miRs) are increasingly recognized as potential regulators of neuropathic pain. Previous evidence has demonstrated that miR-195 is involved in neuropathic pain, but the mechanism remains unclear. To investigate the pathophysiological role of miR-195 and Shh signaling in TN, persistent facial pain was induced by infraorbital nerve chronic constriction injury (CCI-IoN), and facial pain responses were evaluated by Von Frey hairs. qPCR and Western blotting were used to determine the relative expression of miR-195 and Patched1, the major receptor of the Sonic Hedgehog (Shh) signaling pathway, in the caudal brain stem at distinct time points after CCI-IoN. Here, we found that the expression of miR-195 was increased in a rat model of CCI-IoN. In contrast, the expression of Patched1 decreased significantly. Luciferase assays confirmed the binding of miR-195 to Patched1. In addition, the overexpression of miR-195 by an intracerebroventricular (i.c.v) administration of LV-miR-195 aggravated facial pain development, and this was reversed by upregulating the expression of Patched1. These results suggest that miR-195 is involved in the development of TN by targeting Patched1 in the Shh signaling pathway, thus regulating extracellular glutamate.

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Yang  Meiling  Che  Shiyou  Zhang  Yunxiu  Wang  Hongbin  Wei  Tao  Yan  Guorong  Song  Wenqin  Yu  Weiwei 《Journal of plant research》2019,132(6):825-837
Journal of Plant Research - Drought is an important environmental factor that can severely affect plant growth and reproduction. Although many genes related to drought tolerance have been studied...  相似文献   
86.
Recent studies have demonstrated pleiotropic roles of pyruvate kinase isoenzyme type M2 (PKM2) in tumor progression. However, the precise mechanisms underlying the effects of PKM2 on esophageal squamous cell carcinoma (ESCC) metastasis and transforming growth factor β1 (TGF-β1)-induced epithelial-mesenchymal transition (EMT) remain to be established. In this study, we observed upregulation of PKM2 in ESCC tissues that was markedly associated with lymph node metastasis and poor prognosis. High PKM2 expression in tumor tissues frequently coincided with the high pSTAT3Tyr705 expression and low E-cadherin expression. Furthermore, altered PKM2 expression was significantly associated with proliferation, migration, and invasion of ESCC cells, in addition to expression patterns of EMT markers (Snail, E-cadherin, and vimentin) and pSTAT3Tyr705/STAT3 ratio. Overexpression of STAT3 significantly attenuated the effects of PKM2 knockdown on cell proliferation and motility as well as expression of pSTAT3 Tyr705 and EMT markers. Consistently, stable short hairpin RNA (shRNA)-mediated silencing of PKM2 reversed the effects of TGF-β1 treatment, specifically, upregulation of PKM2, phosphorylation of STAT3 at Tyr705, and increased EMT, migration, and invasion. We propose that PKM2 regulates cell proliferation, migration, and invasion via phosphorylation of STAT3 through TGF-β1-induced EMT. Our findings collectively provide mechanistic insights into the tumor-promoting role of PKM2, supporting its prognostic value and the therapeutic utility of PKM2 inhibitors as potential antitumor agents in ESCC.  相似文献   
87.
In this experiment, the cross-talk betweenNotch and the NF-κB signaling pathway was examined to reveal the mechanism of slowing down the type II collagen (ColII) and aggrecan degeneration affected by inflammatory cytokines. The expression levels of ColII and aggrecan in the intervertebral disc were observed through immunohistochemistry and hematoxylin-eosin staining+alcian blue staining, respectively. The expression levels of ColII, aggrecan, Runx2, and NF-κB in the nuclei of human nucleus pulposus cells (hNPCs) in each group, as well as the phosphorylation and acetylation levels of p65, were examined through Western blot analysis. The 293T cells were transfected with a plasmid containing the overexpressed relative domain of Notch1 intracellular domain (NICD1), and immunoprecipitation (IP) was performed to observe the combination of NICD1 and p65. HNPCs were transfected with a lentiviral-contained overexpression lacking the ANK region of NICD1, and IP was performed to observe the combination of NICD1 and p65. The expression of ColII and aggrecan in the intervertebral disc culture increased when γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-1-alanyl]-Sphenylglycine t-butyl ester (DAPT) was added to the disc culture medium. Western blot revealed that DAPT inhibited p65 phosphorylation and acetylation, and the p65 and p50 levels in the nucleus decreased. NICD1 was found to be combined with p65 in contrast to the reverse consequences after ANK domain deletion in hNPCs. In nucleus pulposus cells, the combination of p65 and the ANK domain of NICD1 is a critical procedure for the degeneration related to the NF-κB signaling pathway activation induced by IL-1β and TNF-α.  相似文献   
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EIF1A encodes a translation initiation factor in eukaryocyte and aberrant expression of EIF1A is deemed to be associated with dysfunctions in intracranial diseases. The goal of this research was to explore the impacts of EIF1A on progression of human pituitary adenoma (PA). We employed immunohistochemistry to assess the expression of EIF1A in PA and para-carcinoma tissues. After constructing EIF1A-knockdown cell models via lentivirus infection, we examined cell proliferation through CCK-8 assay and Celigo cell counting assay. Flow cytometry was utilized to detect cell apoptosis and the migration ability of experimental cells was estimated using wound-healing assay and Transwell assay. The activity of the apoptosis-related factor, Caspase 3, was also examined via Caspase 3 activity assay. Lastly, in vivo xenograft mouse models were established to verify findings derived from in vitro cell models. Our results affirmed upregulation of EIF1A in PA cells and revealed that depletion of EIF1A could seriously limit cell proliferation and weaken the capacity of cell migration, and also enhance apoptosis of tumor cells. Mechanistically, degradation in cell growth mediated by EIF1A knockdown may involve in activation of MAPK signaling but inactivation of PI3K/AKT signaling pathway. This study indicates EIF1A plays a prominent role in facilitating tumor cell proliferation and migration which may further contribute to PA progression.Key words: EIF1A, Pituitary adenoma, Cell proliferation, Cell migration, MAPK  相似文献   
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