A DNA-based nanocarrier for efficient cancer therapy / 药物分析学报

The study aimed to achieve enhanced targeted cytotoxicity and cell-internalization of cisplatin-loaded deoxyribonucleic acid-nanothread (CPT-DNA-NT),mediated by scavenger receptors into HeLa cells.DNA-NT was developed with stiff-topology utilizing circular-scaffold to encapsulate CPT.Atomic force microscopy (AFM) characterization of the DNA-NT showed uniformity in the structure with a diameter of 50-150 nm and length of 300-600 nm.The successful fabrication of the DNA-NT was confirmed through native-polyacrylamide gel electrophoresis analysis,as large the molecular-weight (polymeric) DNA-NT did not split into constituting strands under applied current and voltage.The results of cell viability confirmed that blank DNA-NT had the least cytotoxicity at the highest concentration (512 nM) with a viability of 92％ as evidence of its biocompatibility for drug delivery.MTT assay showed superior cyto-toxicity of CPT-DNA-NT than that of the free CPT due to the depot release of CPT after DNA-NT inter-nalization.The DNA-NT exhibited targeted cell internalizations with the controlled intracellular release of CPT (from DNA-NT),as illustrated in confocal images.Therefore,in vitro cytotoxicity assessment through flow cytometry showed enhanced apoptosis (72.7％) with CPT-DNA-NT (compared to free CPT;64.4％).CPT-DNA-NT,being poly-anionic,showed enhanced endocytosis via scavenger receptors.

Versatile Functions of Caveolin-1 in Aging-related Diseases / 전남의대학술지

Caveolin-1 (Cav-1) is a trans-membrane protein that is a major component of the caveolae structure on the plasma membrane. Cav-1 is involved in the regulation of various cellular processes, including cell growth, differentiation, endocytosis, and in particular it has been implied in cellular senescence. Here we review current knowledge about Cav-1 in cellular signaling and discuss the role of Cav-1 in aging-related diseases.

A preliminary study on the interaction between Asn-Gly-Arg (NGR)-modified multifunctional nanoparticles and vascular epithelial cells

Previously developed Asn-Gly-Arg (NGR) peptide-modified multifunctional poly(ethyleneimine)-poly(ethylene glycol) (PEI-PEG)-based nanoparticles (TPIC) have been considered to be promising carriers for the co-delivery of DNA and doxorubicin (DOX). As a continued effort, the aim of the present study was to further evaluate the interaction between TPIC and human umbilical vein endothelial cells (HUVEC) to better understand the cellular entry mechanism. In the present investigation, experiments relevant to co-localization, endocytosis inhibitors and factors influencing the internalization were performed. Without any treatment, there was no co-localization between aminopeptidase N/CD13 (APN/CD13) and caveolin 1 (CAV1). However, co-localization between CD13 and CAV1 was observed when cells were incubated with an anti-CD13 antibody or TPIC. As compared with antibody treatment, TPIC accelerated the speed and enhanced the degree of co-localization. TPIC entered HUVEC not only together with CD13 but also together with CAV1. However, this internalization was not dependent on the enzyme activity of CD13 but could be inhibited by methyl--eyclodextfin (MCD), further identifying the involvement of caveolae-mediated endocytosis (CvME). This conclusion was also verified by endocytosis inhibitor experiments.

Versatile Functions of Caveolin-1 in Aging-related Diseases / 전남의대학술지

Caveolin-1 (Cav-1) is a trans-membrane protein that is a major component of the caveolae structure on the plasma membrane. Cav-1 is involved in the regulation of various cellular processes, including cell growth, differentiation, endocytosis, and in particular it has been implied in cellular senescence. Here we review current knowledge about Cav-1 in cellular signaling and discuss the role of Cav-1 in aging-related diseases.

Caracterização das proteínas caveolinas -1 e -2 na placenta de conceptos bovinos clonados transgênicos / Caracterization of caveolin -1 and -2 proteins in cloned and transgenic placenta of cattle

A utilização da transgenia com a proteína fluorescente verde (GFP) como marcador de células de origem fetal nas placentas de clones bovinos servirá de modelo inédito para estudo morfofisiológico e imunológico da interação materno-fetal, visto que possibilitará o seu mapeamento, diferenciando as células fetais das maternas. Tal modelo terá aplicação direta, principalmente porque estes são animais que apresentam problemas em relação ao seu desenvolvimento. Com o auxílio deste modelo, pretende-se verificar o transporte de substâncias entre a mãe e o feto via endocitose, pela imunolocalização das proteínas chamadas de caveolinas. Para tanto foram utilizados 06 bovinos clonados e 30 bovinos de inseminação artificial (IA) com idade até 90 dias de gestação, os quais tiveram seu desenvolvimento interrompido mediante abate humanitário das receptoras e ovariosalpingohisterectomia, com posterior recuperação do útero gestante. Foram coletados os placentônios e o cório. Uma parte das amostras foi recortada e fixada, por imersão, em solução de parafolmaldeído a 4% ou formoldeído a 10% em tampão fosfato de sódio (PBS) a 0,1M pH 7.4, solução de Zamboni (4% de paraformoldeído, 15% de ácido pícrico, em tampão fosfato de sódio a 0,1M pH 7.4), metacarn (60% de metanol, 30% de clorofórmio, e 10% de ácido acético glacial), para verificação da morfologia e realização de imuno-histoquímica para as proteínas caveolinas -1 e -2 (CAV -1 e CAV-2)...

The transgenic application of green fluorescent protein (GFP) as fetal cell marker on cattle cloned placenta could provide an exclusive model for studying the morphologic and immunologic maternal-fetal interactions, providing information about its mapping, distinguishing the fetal from maternal cells. This model will have direct application, mainly because these animals present problems during its development. With this model's support, we intend to verify the substances transport between mother and fetus during endocytosis, through the immunolocalization of protein named caveolae. For these, we used 06 cloned bovine and 30 cattle samples of artificial insemination (AI) with 90 days of pregnancy, which had been their development interrupted by humanitarian slaughter of the recipient and recovery of the pregnant uterus. We collected the placentome and the chorion. A part of the samples was cut and fixed, by immersion, on a solution containing 4% of parafomaldehyde or 10% of formaldehyde on a sodium phosphate buffer (PBS), at 0,1M pH 7.4, Zamboni solution (4% of paraformaldehyde, 15% of picric acid, on sodium phosphate buffer 0,1M pH 7.4), metacarn (60% of metanol, 30% of chloroform, and 10% glacial acetic acid), for morphologic and immunohistochemistry verification for caveolinas proteins -1 and -2 (CAV -1 and CAV- 2). The caveolins -1 were found in fetal and maternal villi, but its strongest staining was observed in the endometrial stroma. The caveolins -2 had positive staining in trophoblast and chorioallantoic membrane, and specifically in giant trophoblastic binucleated cell. Therefore the results were compared between cloned cattle and from AI or natural mating, for assisting on detection of the reason of many placental alterations, embryonic losses, spontaneous abortion, post-natal mortality and large offspring syndrome on laboratory-manipulated animals. The result suggests that the proteins caveolins -1 and -2 (CAV-1 and CAV-2)...

The change of Caveolin-3 in the rabbit skeletal muscle when ischemia-reperfusion injury / 中华显微外科杂志

Objective To observe the damage degree and expression pattern of Caveolin-3 mRNA by ischemia-reperfusion injury in rabbits of skeletal muscle cell at different phases.Methods In this study,from April 2013 to December 2013,30 lower limbs of 15 Chinese White Rabbits were used and divided into two groups:all the left lower limbs were experimental group,which were made as an experimental model of ischemia-reperfusion injury by occluding left common iliac artery using noninvasive vascular.All the right lower limbs without surgical treatment were the control group.Gastrocnemius samples were obtained at 4h and 8h after reperfusion and handled by HE staining and observed by optical microscopy.By Real-time PCR,Caveolin-3/GAPDH mRNA were detected.Results HE stain showed:in control group,there was no edema,degeneration and inflammatory cell infiltration; in experi-meatal group,muscle cell degeneration had occured at ischemic 5 h.The edema was aggravated,a large number vacuole were formed and inflammatory cell were infiltrated at 4 h reperfusion.Reperfusion injury at 8h significantly reduced compared to 4 h.The Caveolin-3/GAPDH mRNA expression levels by SPSS 19.0 showed:Control group:1.026 ± 0.065,1.004 ±0.037,1.022 ±0.051,experimental group:1.159 ±0.073,1.445 ±0.053,1.208 ±0.058 at ischemic 5 h,4 h and 8 h reperfusion,respectively.On-line analysis of variance cases of ischemic 5 h and 4 h reperfusion and 8 h reperfusion,the experimental group than the control group were increased,with statistical significance (P ＜ 0.05).The experimental group of ischemic 5 h and 8 h reperfusion was no significant difference (P ＞ 0.05).It showed Caveolin-3 mRNA expression levels in ischemia-reperfusion 8 h group returned to normal.There was significant statistical difference between the ischemic 5 h and 4 h reperfusion (P ＜ 0.05).There was significant statistical difference between the 4 h reperfusion and 8 h reperfusion (P ＜ 0.05).Conclusion The expression of Caveolin-3 in experimental group showed a trend of first increased and then decreased.The expression levels of Caveolin-3 mRNA in skeletal muscle cells after ischemia-reperfusion injury is consistent with the development and progression of muscle cell damage.The results indicate that Caveolin-3 may play a control role in the injury and recovery of skeletal muscle cell.

Effect of m-calpain in PKCα-mediated proliferation of pulmonary artery smooth muscle cells by low dose of ouabain.

There is growing evidence that ouabain, a cardiotonic steroid may promote growth of cardiac and vascular myocytes, indicating its novel role in cell growth and proliferation, without appreciable inhibition of the sodium pump. The mechanism(s) by which low dose of ouabain produces pulmonary artery smooth muscle cell proliferation, a prerequisite for right ventricular hypertrophy, is currently unknown. Here, we analyzed the effects of low dose of ouabain (10 nM) on increase in [Ca2+]i, m-calpain and protein kinase C (PKC) activities on pulmonary artery smooth muscle cell proliferation and determined their sequential involvement in this scenario. We treated bovine pulmonary artery smooth muscle cells with a low dose of ouabain (10 nM) and determined [Ca2+]i in the cells by fluorometric assay using fura2-AM, m-calpain activity by fluorometric assay using SLLVY-AMC as the substrate, PKC activity using an assay kit and assay of Na+/K+ATPase activity spectrophotometrically. We purified m-calpain and PKCα by standard chromatographic procedure by HPLC and then studied cleavage of the purified PKCα by m-calpain using Western immunoblot method. Subsequently, we performed cell proliferation assay utilizing the redox dye resazunin. We used selective inhibitors of [Ca2+]i (BAPTA-AM), m-calpain (MDL28170), PKCα (Go6976) and determined their involvement in ouabain (10 nM)-mediated smooth muscle cell proliferation. Our results suggested that treatment of bovine pulmonary artery smooth muscle cells with a low dose of ouabain (10 nM) increased [Ca2+]i and subsequently stimulated m-calpain activity and proteolytically activated PKCα in caveolae (signaling microdomain also known as signalosomes) of the cells. Upon activation, PKCα increased the smooth muscle cell proliferation via Go/G1 to S/G2-M phase transition. Thus, [Ca2+]i-mCalpain-PKCα signaling axis plays a crucial role during low dose of ouabain-mediated pulmonary artery smooth muscle cell proliferation.

Modulation of the caveolin-3 localization to caveolae and STAT3 to mitochondria by catecholamine-induced cardiac hypertrophy in H9c2 cardiomyoblasts

We investigated the effect of phenylephrine (PE)- and isoproterenol (ISO)-induced cardiac hypertrophy on subcellular localization and expression of caveolin-3 and STAT3 in H9c2 cardiomyoblast cells. Caveolin-3 localization to plasma membrane was attenuated and localization of caveolin-3 to caveolae in the plasma membrane was 24.3% reduced by the catecholamine-induced hypertrophy. STAT3 and phospho-STAT3 were up-regulated but verapamil and cyclosporin A synergistically decreased the STAT3 and phospho-STAT3 levels in PE- and ISO-induced hypertrophic cells. Both expression and activation of STAT3 were increased in the nucleus by the hypertrophy. Immunofluorescence analysis revealed that the catecholamine-induced hypertrophy promoted nuclear localization of pY705-STAT3. Of interest, phosphorylation of pS727-STAT3 in mitochondria was significantly reduced by catecholamine-induced hypertrophy. In addition, mitochondrial complexes II and III were greatly down-regulated in the hypertrophic cells. Our data suggest that the alterations in nuclear and mitochondrial activation of STAT3 and caveolae localization of caveolin-3 are related to the development of the catecholamine-induced cardiac hypertrophy.

Caveolae and multidrug resistance of tumor cells / 肿瘤研究与临床

Caveolae is a specified micro-domain of plasma membrane, which consists of caveolin and many lipid molecules and membrane proteins. Caveolae plays important roles in internalization of extra-membrane molecules, transmembrane signal transdution and transport of cholesterin. Recent studies indicated that caveolae and its components were up-regulated in multidrug resistant tumor cells and might participate the development of multidrug resistance of tumor cells. This paper concentrated on the role of caveolae in tumor multidrug resistance.

Expression of caveolin-1 in tumor and its clinical significance / 基础医学与临床

Caveolin-1(Cav-1) is a scaffold protein of caveolae that acts as a tumor modulator by interacting with cell adhesion molecules and signaling receptors.Evidence from a variety of studies indicate that caveolin-1 exhibits the heterogeneity of Cav-1 expression in different tumors.Current research has clearly established a role for Cav-1 as a a novel prognostic marker,Future studies will undoubtedly offer novel exciting opportunities to develop anti-cancer therapies.

Modulation of the caveolin-3 and Akt status in caveolae by insulin resistance in H9c2 cardiomyoblasts

We investigated glucose uptake and the translocation of Akt and caveolin-3 in response to insulin in H9c2 cardiomyoblasts exposed to an experimental insulin resistance condition of 100 nM insulin in a 25 mM glucose containing media for 24 h. The cells under the insulin resistance condition exhibited a decrease in insulin-stimulated 2-deoxy[3 H]glucose uptake as compared to control cells grown in 5 mM glucose media. In addition to a reduction in insulin-induced Akt translocation to membranes, we observed a significant decrease in insulin-stimulated membrane association of phosphorylated Akt with a consequent increase of the cytosolic pool. Actin remodeling in response to insulin was also greatly retarded in the cells. When translocation of Akt and caveolin-3 to caveolae was examined, the insulin resistance condition attenuated localization of Akt and caveolin-3 to caveolae from cytosol. As a result, insulin-stimulated Akt activation in caveolae was significantly decreased. Taken together, our data indicate that the decrease of glucose uptake into the cells is related to their reduced levels of caveolin-3, Akt and phosphorylated Akt in caveolae. We conclude that the insulin resistance condition induced the retardation of their translocation to caveolae and in turn caused an attenuation in insulin signaling, namely activation of Akt in caveolae for glucose uptake into H9c2 cardiomyoblasts.

Calcium sensing receptor forms complex with and is up-regulated by caveolin-1 in cultured human osteosarcoma (Saos-2) cells

The calcium sensing receptor (CaSR) plays an important role for sensing local changes in the extracellular calcium concentration ([Ca2+]o) in bone remodeling. Although the function of CaSR is known, the regulatory mechanism of CaSR remains controversial. We report here the regulatory effect of caveolin on CaSR function as a process of CaSR regulation by using the human osteosarcoma cell line (Saos-2). The intracellular calcium concentration ([Ca2+]i) was increased by an increment of [Ca2+]o. This [Ca2+]i increment was inhibited by the pretreatment with NPS 2390, an antagonist of CaSR. RT-PCR and Western blot analysis of Saos-2 cells revealed the presence of CaSR, caveolin (Cav)-1 and -2 in both mRNA and protein expressions, but there was no expression of Cav-3 mRNA and protein in the cells. In the isolated caveolae-rich membrane fraction from Saos-2 cells, the CaSR, Cav-1 and Cav-2 proteins were localized in same fractions (fraction number 4 and 5). The immuno-precipitation experiment using the respective antibodies showed complex formation between the CaSR and Cav-1, but no complex formation of CaSR and Cav-2. Confocal microscopy also supported the co-localization of CaSR and Cav-1 at the plasma membrane. Functionally, the [Ca2+]o- induced [Ca2+]i increment was attenuated by the introduction of Cav-1 antisense oligodeoxynucleotide (ODN). From these results, in Saos-2 cells, the function of CaSR might be regulated by binding with Cav-1. Considering the decrement of CaSR activity by antisense ODN, Cav-1 up-regulates the function of CaSR under normal physiological conditions, and it may play an important role in the diverse pathophysiological processes of bone remodeling or in the CaSR- related disorders in the body.

The function of caveolins in neoplasia and its progressing / 中国癌症杂志

Caveolin,a membrane protein of 21-24 k,is the main structural component of caveolae,it plays quite a diverse functional role in maintaining vital activities of cells like endocytosis,cholesterol transport,cell membrane composition,and transduction of transmembrane signal to some virus involved in the processes of virus infection.Caveolin-1 also is a key regulator of multiple steps of oncogenesis and tumor development.Caveolin-1 can also serve as a negative regulator in proliferation,apoptosis,invasion and metastasis in varieties of cancer cells.There are some conflicting roles in different tumors,this review summarized the recent advances in the function of caveolin in cancers.

Influence of caveolin-1 on the ET-1-induced VSMC proliferation / 中国病理生理杂志

AIM: To investigate the effect of caveolin-1 on the endothelin-1 (ET-1)-induced vascular smooth muscle cells (VSMC) proliferation. METHODS: The -thymidine (TdR) incorporation, immunofluorescence assays and western blotting were used in this study. RESULTS: The ETA receptor specific antagonist BQ123 inhibited the increase in TdR incorporation in response to ET-1 on VSMC. Immunofluorescence assays showed that caveolin-1 was mostly distributed in plasmalemma of VSMC. After 24 h treatment of VSMC with ET-1, the expression of caveolin-1 in VSMC was significantly decreased. Western blotting showed that ET-1 inhibited the expression of caveolin-1 in VSMC, BQ123 reversed the effect of ET-1. CONCLUSION: Caveolin-1 was mostly distributed in plasmalemma of VSMC. ET-1 downregulated caveolin-1 expression in VSMC via ETA receptor.