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181.
Tissue expression and cellular localization of phospholipid hydroperoxide glutathione peroxidase (PHGPx) mRNA in male mice 总被引:1,自引:0,他引:1
Baek IJ Seo DS Yon JM Lee SR Jin Y Nahm SS Jeong JH Choo YK Kang JK Lee BJ Yun YW Nam SY 《Journal of molecular histology》2007,38(3):237-244
Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is an ubiquitous antioxidant enzyme, but the exact expression pattern
in mammalian tissues is still unknown. The expression and cellular localization of PHGPx mRNA were examined in male mice using
real time-polymerase chain reaction and in situ hybridization techniques. The rank order of PHGPx mRNA expression across tissues exhibiting substantial levels of expression
was:testes ≫ heart > cerebrum ≥ ileum > stomach = liver = jejunum ≥ epididymis. In testes, PHGPx mRNA was highly expressed
in spermiogenic cells and Leydig cells. The signal was also expressed in the molecular layer, Purkinje cell layer, and white
matter of cerebellum, the pituicytes of neurohypophysis, the parafollicular cells and follicular basement membrane of thyroid,
the exocrine portion of pancreas, the tubular epithelium of kidney, the smooth muscle cells of arteries, and the red pulp
of spleen. In the gastrointestinal tract, PHGPx mRNA expression was mainly observed in the keratinized surface epithelium
of forestomach, the submucosal glands and serosa layers, and further the Paneth cells of intestines. PHGPx mRNA appeared to
be ubiquitously expressed in the parenchyma of heart, liver, and lung. These results indicate that PHGPx exhibits a cell-
and tissue-specific expression pattern in mice. 相似文献
182.
Kyung Eun Kim Eun Ae Jeong Hyun Joo Shin Jong Youl Lee Eun Bee Choi Hyeong Seok An Kyung-Ah Park Zhen Jin Dong Kun Lee Tamas L. Horvath Gu Seob Roh 《Biochemical and biophysical research communications》2019,508(1):123-129
Hypothalamic inflammation has been known as a contributor to high-fat diet (HFD)-induced insulin resistance and obesity. Myeloid-specific sirtuin 1 (SIRT1) deletion aggravates insulin resistance and hypothalamic inflammation in HFD-fed mice. Neurogranin, a calmodulin-binding protein, is expressed in the hypothalamus. However, the effects of myeloid SIRT1 deletion on hypothalamic neurogranin has not been fully clarified. To investigate the effect of myeloid SIRT1 deletion on food intake and hypothalamic neurogranin expression, mice were fed a HFD for 20 weeks. Myeloid SIRT1 knockout (KO) mice exhibited higher food intake, weight gain, and lower expression of anorexigenic proopiomelanocortin in the arcuate nucleus than WT mice. In particular, KO mice had lower ventromedial hypothalamus (VMH)-specific neurogranin expression. However, SIRT1 deletion reduced HFD-induced hypothalamic neurogranin. Furthermore, hypothalamic phosphorylated AMPK and parvalbumin protein levels were also lower in HFD-fed KO mice than in HFD-fed WT mice. Thus, these findings suggest that myeloid SIRT1 deletion affects food intake through VMH-specific neurogranin-mediated AMPK signaling and hypothalamic inflammation in mice fed a HFD. 相似文献
183.
Akie Kobayashi Hye‐Jeong Kim Yuta Tomita Yutaka Miyazawa Nobuharu Fujii Sachiko Yano Chiaki Yamazaki Motoshi Kamada Haruo Kasahara Sachiko Miyabayashi Toru Shimazu Yasuo Fusejima Hideyuki Takahashi 《Physiologia plantarum》2019,165(3):464-475
Plants exhibit helical growth movements known as circumnutation in growing organs. Some studies indicate that circumnutation involves the gravitropic response, but this notion is a matter of debate. Here, using the agravitropic rice mutant lazy1 and space‐grown rice seedlings, we found that circumnutation was reduced or lost during agravitropic growth in coleoptiles. Coleoptiles of wild‐type rice exhibited circumnutation in the dark, with vigorous oscillatory movements during their growth. The gravitropic responses in lazy1 coleoptiles differed depending on the growth stage, with gravitropic responses detected during early growth and agravitropism during later growth. The nutation‐like movements observed in lazy1 coleoptiles at the early stage of growth were no longer detected with the disappearance of the gravitropic response. To verify the relationship between circumnutation and gravitropic responses in rice coleoptiles, we conducted spaceflight experiments in plants under microgravity conditions on the International Space Station. Wild‐type rice seeds were germinated, and the resulting seedlings were grown under microgravity or a centrifuge‐generated 1 g environment in space. We began filming the seedlings 2 days after seed imbibition and obtained images of seedling growth every 15 min. The seed germination rate in space was 92–100% under both microgravity and 1 g conditions. LED‐synchronized flashlight photography induced an attenuation of coleoptile growth and circumnutational movement due to cumulative light exposure. Nevertheless, wild‐type rice coleoptiles still showed circumnutational oscillations under 1 g but not microgravity conditions. These results support the idea that the gravitropic response is involved in plant circumnutation. 相似文献
184.
This study presents a systematic modeling approach for examining the efficiency of the MEOR process based on in situ selective plugging by bacterial biopolymer production and optimization of the nutrient injection strategy to yield the maximum oil recovery. This study focuses on modeling in situ selective plugging by the bacterial biopolymer dextran that is generated by Leuconostoc mesenteroides. Bacterial growth and dextran generation were described by a stoichiometric equation and kinetic reactions using batch model simulation. Based on the parameters for permeability reduction obtained from the sandpack model, the MEOR process was implemented in a pilot-scale system that included a highly permeable thief zone in a low-permeability reservoir. The base MEOR design yielded a 61.5% improvement of the recovery factor compared to that obtained with waterflooding. The parametric simulations revealed that the recovery efficiency was influenced by the amount of dextran, as well as the distribution of dextran, and thus, the injection strategy is critical for controlling the dextran distribution. By incorporating the results from the sensitivity analysis and optimization to determine the optimal design parameters, a 36.7% improvement of the oil recovery was achieved with the optimized MEOR process in comparison with the base case. 相似文献
185.
Lee Yeon Hee Bang Eun-Sook Lee Ji-Hyun Lee Jung-Dong Kang Dae Ryong Hong Jeong Lee Jae-Myeong 《Biological trace element research》2019,188(2):316-325
Biological Trace Element Research - We measured serum concentrations of trace elements and evaluated their clinical significance in relation to treatment outcomes of critically ill patients. A... 相似文献
186.
Chung Hyung-Joo Kim Muwoong Jung Junyang Jeong Na Young 《Neurochemical research》2019,44(8):1964-1976
Neurochemical Research - Schwann cells are essential glial cells in the peripheral nervous system (PNS), and dysfunction of Schwann cells can induce various peripheral neurodegenerative diseases.... 相似文献
187.
Calorie restriction (CR) and the activation of autophagy extend healthspan by delaying the onset of age-associated diseases in most living organisms. Because protein kinase CK2 (CK2) downregulation induces cellular senescence and nematode aging, we investigated CK2’s role in CR and autophagy. This study indicated that CR upregulated CK2’s expression, thereby causing SIRT1 and AMP-activated protein kinase (AMPK) activation. CK2α overexpression, including antisense inhibitors of miR-186, miR-216b, miR-337-3p, and miR-760, stimulated autophagy initiation and nucleation markers (increase in ATG5, ATG7, LC3BII, beclin-1, and Ulk1, and decrease in SQSTM1/p62). The SIRT1 deacetylase, AKT, mammalian target of rapamycin (mTOR), AMPK, and forkhead homeobox type O (FoxO) 3a were involved in CK2-mediated autophagy. The treatment with the AKT inhibitor triciribine, the AMPK activator AICAR, or the SIRT1 activator resveratrol rescued a reduction in the expression of lgg-1 (the Caenorhabditis elegans ortholog of LC3B), bec-1 (the C. elegans ortholog of beclin-1), and unc-51 (the C. elegans ortholog of Ulk1), mediated by kin-10 (the C. elegans ortholog of CK2β) knockdown in nematodes. Thus, this study indicated that CK2 acted as a positive regulator in CR and autophagy, thereby suggesting that these four miRs’ antisense inhibitors can be used as CR mimetics or autophagy inducers. 相似文献
188.
189.
Se-Il Go Gyung Hyuck Ko Won Sup Lee Jeong-Hee Lee Sang-Ho Jeong Young-Joon Lee Soon Chan Hong Woo Song Ha 《Current issues in molecular biology》2022,44(3):1395
TNM stage still serves as the best prognostic marker in gastric cancer (GC). The next step is to find prognostic biomarkers that detect subgroups with different prognoses in the same TNM stage. In this study, the expression levels of epidermal growth factor receptor (EGFR) and cyclin D1 were assessed in 96 tissue samples, including non-tumorous tissue, adenoma, and carcinoma. Then, the prognostic impact of EGFR and cyclin D1 was retrospectively investigated in 316 patients who underwent R0 resection for GC. EGFR positivity increased as gastric tissue became malignant, and cyclin D1 positivity was increased in all the tumorous tissues. However, there was no survival difference caused by the EGFR positivity, while the cyclin D1-postive group had worse overall survival (OS) than the cyclin D1-negative group in stage I GC (10-year survival rate (10-YSR): 62.8% vs. 86.5%, p = 0.010). In subgroup analyses for the propensity score-matched (PSM) cohort, there were also significant differences in the OS according to the cyclin D1 positivity in stage I GC but not in stage II and III GC. Upon multivariate analysis, cyclin D1 positivity was an independent prognostic factor in stage I GC. In conclusion, cyclin D1 may be a useful biomarker for predicting prognosis in stage I GC. 相似文献
190.
Seungyeon Ryu Myeongwoo Jung Chongtae Kim Hoin Kang Sukyoung Han Seongho Cha Seung Min Jeong Eun Kyung Lee 《Cell death & disease》2022,13(4)
HuD, an RNA binding protein, plays a role in the regulation of gene expression in certain types of cells, including neuronal cells and pancreatic β-cells, via RNA metabolism. Its aberrant expression is associated with the pathogenesis of several human diseases. To explore HuD-mediated gene regulation, stable cells expressing short hairpin RNA against HuD were established using mouse neuroblastoma Neuro2a (N2a) cells, which displayed enhanced phenotypic characteristics of cellular senescence. Two approaches, RNA immunoprecipitation (RNA IP)-NanoString profiling and cytokine array, were used to subsequently identify a subset of putative HuD targets that act as senescence-associated secretory phenotype (SASP), including C-C motif ligand 2 (CCL2), CCL20, C-X-C motif chemokine ligand 2 (CXCL2), and interleukin-6 (IL-6). Here, we further demonstrated that HuD regulates the expression of CCL2, a SASP candidate upregulated in cells following HuD knockdown, by binding to the 3′-untranslated region (UTR) of Ccl2 mRNA. Downregulation of HuD increased the level of CCL2 in N2a cells and the brain tissues of HuD knockout (KO) mice. Exposure to γ-irradiation induced cellular senescence in N2a cells and HuD knockdown facilitated stress-induced cellular senescence. Our results reveal that HuD acts as a novel regulator of CCL2 expression, and its aberrant expression may contribute to cellular senescence by regulating SASP production.Subject terms: Senescence, RNA quality control 相似文献