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71.
Breast cancer is one of the most common cancers in women worldwide. The obesity process is normally accompanied by chronic, low-grade inflammation. Infiltration by inflammatory cytokines and immune cells provides a favorable microenvironment for tumor growth, migration, and metastasis. Epidemiological evidence has shown that aspirin is an effective agent against several types of cancer. The aim of this study is to investigate the anti-inflammatory and anti-cancer effects of aspirin on 3T3-L1 adipocytes, 4T1 murine breast cancer cells, and their crosstalk. The results showed that aspirin treatment inhibited differentiation and lipid accumulation by 3T3-L1 preadipocytes, and decreased the secretion of the inflammatory adipokine MCP-1 after stimulation with tumor necrosis factor (TNF)-α or conditioned medium from RAW264.7 cells. In 4T1 cells, treatment with aspirin decreased cell viability and migration, possibly by suppressing MCP-1 and VEGF secretion. Subsequently, culture of 4T1 cells in 3T3-L1 adipocyte-conditioned medium (Ad-CM) and co-culture of 3T3-L1 and 4T1 cells using a transwell plate were performed to clarify the relationship between these two cell lines. Aspirin exerted its inhibitory effects in the transwell co-culture system, as well as the conditioned-medium model. Aspirin treatment significantly inhibited the proliferation of 4T1 cells, and decreased the production of MCP-1 and PAI-1 in both the Ad-CM model and co-culture system. Aspirin inhibited inflammatory MCP-1 adipokine production by 3T3-L1 adipocytes and the cell growth and migration of 4T1 cells. It also broke the crosstalk between these two cell lines, possibly contributing to its chemopreventive properties in breast cancer. This is the first report that aspirin’s chemopreventive activity supports the potential application in auxiliary therapy against obesity-related breast cancer development. 相似文献
72.
P O'Grady S S Huang J S Huang 《Biochemical and biophysical research communications》1991,179(1):378-385
A new type high molecular weight receptor (type V receptor) of transforming growth factor beta (TGF-beta) was recently purified from bovine liver plasma membranes and appears not to be related to receptors previously described for TGF-beta (Pauline O'Grady, Ming-Der Kuo, Joseph J. Baldassare, Shuan Shian Huang and Jung San Huang [1991] J. Biol. Chem. 266:8583-8589). This type V receptor may be important in the regulation of cell growth by TGF-beta. We examined its distribution in a wide range of normal and transformed cells. The type V receptor was found to be expressed in many normal cells including cells of epithelial, endothelial, fibroblastic and chondrocytic origins. However, a number of human epithelial tumor cells (5 out of 6 examined) did not express detectable levels of the type V TGF-beta receptor. These results suggest that loss of the type V receptor may potentially contribute to the transformed state of certain epithelial tumor cells. 相似文献
73.
A S Alam B S Moonga P J Bevis C L Huang M Zaidi 《Biochemical and biophysical research communications》1991,179(1):134-139
Exposure of isolated rat osteoclasts to calcitonin (CT) leads to an abrupt cessation of cell motility (Q effect) followed by cell retraction (R effect). We have previously shown that these effects are mediated by two G proteins that appear to activate separate post-receptor pathways. The present study demonstrates that the Q but not the R effect of CT (0.006 microM) is abolished in the presence of human calcitonin gene-related peptide (CGRP)-(Val8Phe37) (0.5 microM), a fragment analogue of human CGRP. This selective antagonism suggests that the Q effect could result from an action of CT upon a site that is distinct from that producing the R effect. The former site ('amylin site') also appears to interact with related peptides, amylin and CGRP, whilst the latter site ('CT site') specifically interacts with CT. 相似文献
74.
Simone Sabatelli Meike Liu Davide Badano Emiliano Mancini Marco Trizzino Andrew Richard Cline Anders Endrestøl Min Huang Paolo Audisio 《Zoologica scripta》2020,49(1):28-46
The 24 members of the Euro-Asiatic genus Thymogethes are highly specialized pollen beetles associated as larvae with flowers of Lamiaceae Nepetoideae. All members of the genus were analysed in within the framework of an integrative taxonomy approach, which was aimed to reconstruct the phylogenetic relationships, as well as the possible pattern of evolution of their larval-host-plant association. Evidence from multiple molecular markers [COI; 16S; H3], combined with an estimation of divergence times using an average rate of 0.0177 substitutions/site/My among branches, placed the origin of the genus at a minimum of 9–10 Mya. This date of origin approximates the known evolution of the host plants in Euro-Mediterranean areas. Evidence from combined molecular and cladistic morphological analyses resulted in suitable agreement with the previously established morphology-based systematics of the genus, although members of the exilis species-group were split into three clades. The only disagreement between results of this new combined phylogeny and previous classification is in the exclusion of “Thymogethes” grenieri. This species is herein positioned outside the genus, based on molecular evidence. Our analysis depicts several Thymogethes species differentiating in the last few Mys, specifically those included in the T. lugubris species-group. Combined evidence from DNA, morphology and ancestral state parsimony reconstruction of larval-host-plant associations suggests that subtribe Menthinae likely represents the ancestral host plants, with a series of independent host shifts during the radiation of the clade, in association first with Menthinae and subsequently with Lavandulinae and Nepetinae. Steno-oligophagy is the most frequent (86%) condition, while strictly monophagous species are less numerous (14%). 相似文献
75.
Jiechun Huang Rongrong Jiang Xianglin Chu Fangrui Wang Xiaotian Sun Yiqing Wang Liewen Pang 《Cell biochemistry and function》2020,38(8):1047-1055
Myocardial infarction (MI) leads to cardiac remodelling and heart failure. Cardiomyocyte apoptosis is considered a critical pathological phenomenon accompanying MI, but the pathogenesis mechanism remains to be explored. MicroRNAs (miRs), with the identity of negative regulator of gene expression, exist as an important contributor to apoptosis. During the experiment of this study, MI mice models were successfully established and sequencing data showed that the expression of miR-23a-5p was significantly enhanced during MI progression. Further steps were taken and it showed that apoptosis of cardiac cells weakened as miR-23a-5p was downregulated and on the contrary that apoptosis strengthened with the overexpression of miR-23a-5p. To explore its working mechanisms, bioinformatics analysis was conducted by referring to multi-databases to predict the targets of miR-23a-5p. Further analysis suggested that those downstream genes enriched in several pathways, especially in the PI3K/Akt singling pathway. Furthermore, it demonstrated that miR-23a-5p was negatively related to the phosphorylation of PI3K/Akt, which plays a critical role in triggering cell apoptosis during MI. Recilisib-activated PI3K/Akt singling pathway could restrain apoptosis from inducing miR-23a-5p overexpression, and Miltefosine-blocked PI3K/Akt singling pathway could restrict apoptosis from inhibiting miR-23a-5p reduction. In conclusion, these findings revealed the pivotal role of miR-23a-5p-PI3K/Akt axis in regulating apoptosis during MI, introducing this novel axis as a potential indicator to detect ischemic heart disease and it could be used for therapeutic intervention. 相似文献
76.
77.
Dhanjoo N. Ghista Sung-Cheng Huang Meyer Resnikoff 《Bulletin of mathematical biology》1973,35(5-6):549-563
A method is presented for the simultaneous determination of (i) the blood flow to the organs and (ii) the cardiac output.
Part I of the paper deals with the analysis of ann compartment (organ) vascular system model. The data, employed in the analysis, consists of continuous monitoring of the amounts
of indicatorM
i
in the organs (or compartments). An analysis for determination of the cardiac output and the absolute flows to the organs
is presented. Since it is difficult to isolate certain organ systems and measure the amounts of indicator in them exclusively,
a more realistic model of then compartment vascular system is presented in Part II. Herein, the analysis has accounted for the finite transit time, of the
indicator, from one organ system to another. Further, estimation theory is employed to make estimates of blood flow to different
organs by taking note of (i) the measurement errors due to the detectors' monitoring (for an organ system) some combination
ofM
i
's instead of theM
i
for the particulari
th organ and (ii) noise uncertainties introduced by the measuring instruments. 相似文献
78.
Hui-bin Zhang Ya-an Zhang Guan-zhong Wu Jin-pei Zhou Wen-long Huang Xiao-wen Hu 《Bioorganic & medicinal chemistry letters》2009,19(6):1740-1744
A novel class of sulfonylurea and thiourea derivatives substituted with benzenesulfonamide groups were designed and synthesized. The target compounds were assayed for the effects on the insulin release of isolated rat pancreatic islets and the glucose transport in adipocytes of rats. Some of them exhibited high potency. Compound 10 also had potent antiplatelet activity and showed an excellent property to protect collagen–epinephrine-induced mice mortality as well as plasma glucose-lowering activity in vivo. The preliminary pharmacological profile of compound 10 showed that it might be useful in the treatment of diabetics with cardiovascular and nephropathy complications. 相似文献
79.
80.