scholarly journals Combination PPARγand RXR Agonist Treatment in Melanoma Cells: Functional Importance of S100A2

PPAR Research ◽  
2010 ◽  
Vol 2010 ◽  
pp. 1-8 ◽  
Author(s):  
Joshua P. Klopper ◽  
Vibha Sharma ◽  
Reid Bissonnette ◽  
Bryan R. Haugen
Keyword(s):  
Calcium Binding ◽  
Hormone Receptors ◽  
Amelanotic Melanoma ◽  
Antiproliferative Effects ◽  
Over Expression ◽  
Poorly Differentiated ◽  
Insight Into ◽  
Synergistic Increase

Nuclear hormone receptors, including RXR and PPARγ, represent novel therapeutic targets in melanoma. We have previously shown that the DRO subline of the amelanotic melanoma A375 responds to rexinoid and thiazolidinedione (TZD) treatmentin vitroandin vivo. We performed microarray analysis of A375(DRO) after TZD and combination rexinoid/TZD treatment in which the calcium binding protein S100A2 had increased expression after rexinoid or TZD treatment and a synergistic increase to combination treatment. Increased S100A2 expression is dependent on an intact PPARγreceptor, but it is not sufficient to mediate the antiproliferative effects of rexinoid/TZD treatment. Over expression of S100A2 enhanced the effect of rexinoid and TZD treatment while inhibition of S100A2 expression attenuated the response to rexinoid/TZD treatment, suggesting that S100A2 is necessary for optimal response to RXR and PPARγactivation by respective ligands. In summary, we have identified potential downstream mediators of rexinoid and TZD treatment in a poorly differentiated melanoma and found that alterations in S100A2 expression affect RXR and PPARγsignaling in A375(DRO) cells. These studies provide insight into potential mechanisms of tumor response or resistance to these novel therapies.

Ultrastructural observations on the in vitro cytoadherence of Plasmodium falciparum infected red blood cells

1990 ◽  
Vol 48 (3) ◽  
pp. 914-915
Author(s):  
D.J.P. Ferguson ◽  
A.R. Berendt ◽  
J. Tansey ◽  
K. Marsh ◽  
C.I. Newbold
Keyword(s):  
Plasmodium Falciparum ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Umbilical Vein ◽  
Cell Types ◽  
Amelanotic Melanoma ◽  
Cytoplasmic Process ◽  
Umbilical Vein Endothelial Cells

In human malaria, the most serious clinical manifestation is cerebral malaria (CM) due to infection with Plasmodium falciparum. The pathology of CM is thought to relate to the fact that red blood cells containing mature forms of the parasite (PRBC) cytoadhere or sequester to post capillary venules of various tissues including the brain. This in vivo phenomenon has been studied in vitro by examining the cytoadherence of PRBCs to various cell types and purified proteins. To date, three Ijiost receptor molecules have been identified; CD36, ICAM-1 and thrombospondin. The specific changes in the PRBC membrane which mediate cytoadherence are less well understood, but they include the sub-membranous deposition of electron-dense material resulting in surface deformations called knobs. Knobs were thought to be essential for cytoadherence, lput recent work has shown that certain knob-negative (K-) lines can cytoadhere. In the present study, we have used electron microscopy to re-examine the interactions between K+ PRBCs and both C32 amelanotic melanoma cells and human umbilical vein endothelial cells (HUVEC).We confirm previous data demonstrating that C32 cells possess numerous microvilli which adhere to the PRBC, mainly via the knobs (Fig. 1). In contrast, the HUVEC were relatively smooth and the PRBCs appeared partially flattened onto the cell surface (Fig. 2). Furthermore, many of the PRBCs exhibited an invagination of the limiting membrane in the attachment zone, often containing a cytoplasmic process from the endothelial cell (Fig. 2).

scholarly journals Plant-Derived Extracellular Vesicles: Current Findings,Challenges, and Future Applications

Membranes ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 411
Author(s):  
Nader Kameli ◽  
Anya Dragojlovic-Kerkache ◽  
Paul Savelkoul ◽  
Frank R. Stassen
Keyword(s):  
Human Health ◽  
Extracellular Vesicles ◽  
Preliminary Results ◽  
In Vivo Experiments ◽  
Health And Disease ◽  
Conducting Research ◽  
Protocol Standardization ◽  
Insight Into

In recent years, plant-derived extracellular vesicles (PDEVs) have gained the interest of many experts in fields such as microbiology and immunology, and research in this field has exponentially increased. These nano-sized particles have provided researchers with a number of interesting findings, making their application in human health and disease very promising. Both in vitro and in vivo experiments have shown that PDEVs can exhibit a multitude of effects, suggesting that these vesicles may have many potential future applications, including therapeutics and nano-delivery of compounds. While the preliminary results are promising, there are still some challenges to face, such as a lack of protocol standardization, as well as knowledge gaps that need to be filled. This review aims to discuss various aspects of PDEV knowledge, including their preliminary findings, challenges, and future uses, giving insight into the complexity of conducting research in this field.

scholarly journals Exosomal S100A4 derived from highly metastatic hepatocellular carcinoma cells promotes metastasis by activating STAT3

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Haoting Sun ◽  
Chaoqun Wang ◽  
Beiyuan Hu ◽  
Xiaomei Gao ◽  
Tiantian Zou ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cancer Progression ◽  
Calcium Binding ◽  
Tumor Metastasis ◽  
Metastatic Potential ◽  
Functional Roles ◽  
Stat3 Phosphorylation ◽  
Hcc Cells

AbstractIntercellular cross-talk plays important roles in cancer progression and metastasis. Yet how these cancer cells interact with each other is still largely unknown. Exosomes released by tumor cells have been proved to be effective cell-to-cell signal mediators. We explored the functional roles of exosomes in metastasis and the potential prognostic values for hepatocellular carcinoma (HCC). Exosomes were extracted from HCC cells of different metastatic potentials. The metastatic effects of exosomes derived from highly metastatic HCC cells (HMH) were evaluated both in vitro and in vivo. Exosomal proteins were identified with iTRAQ mass spectrum and verified in cell lines, xenograft tumor samples, and functional analyses. Exosomes released by HMH significantly enhanced the in vitro invasion and in vivo metastasis of low metastatic HCC cells (LMH). S100 calcium-binding protein A4 (S100A4) was identified as a functional factor in exosomes derived from HMH. S100A4rich exosomes significantly promoted tumor metastasis both in vitro and in vivo compared with S100A4low exosomes or controls. Moreover, exosomal S100A4 could induce expression of osteopontin (OPN), along with other tumor metastasis/stemness-related genes. Exosomal S100A4 activated OPN transcription via STAT3 phosphorylation. HCC patients with high exosomal S100A4 in plasma also had a poorer prognosis. In conclusion, exosomes from HMH could promote the metastatic potential of LMH, and exosomal S100A4 is a key enhancer for HCC metastasis, activating STAT3 phosphorylation and up-regulating OPN expression. This suggested exosomal S100A4 to be a novel prognostic marker and therapeutic target for HCC metastasis.

scholarly journals Peptide drugs for photopharmacology: how much of a safety advantage can be gained by photocontrol?

2020 ◽  
Vol 2 (1) ◽  
pp. FDD28 ◽  
Author(s):  
Oleg Babii ◽  
Sergii Afonin ◽  
Tim Schober ◽  
Liudmyla V Garmanchuk ◽  
Liudmyla I Ostapchenko ◽  
...  
Keyword(s):  
Chemotherapeutic Agent ◽  
In Vitro Cytotoxicity ◽  
Pharmacokinetic Parameters ◽  
Cancer Model ◽  
Pharmacokinetic Properties ◽  
Insight Into ◽  
Safety Advantage ◽  
Murine Cancer Model

Aim: To verify whether photocontrol of biological activity could augment safety of a chemotherapeutic agent. Materials & methods: LD50 values for gramicidin S and photoisomeric forms of its photoswitchable diarylethene-containing analogs were determined using mice. The results were compared with data obtained from cell viability measurements taken for the same compounds. Absorption, Distribution, Metabolism, and Elimination (ADME) tests using a murine cancer model were conducted to get insight into the underlying reasons for the observed in vivo toxicity. Results: While in vitro cytotoxicity values of the photoisomers differed substantially, the differences in the observed LD50 values were less pronounced due to unfavorable pharmacokinetic parameters. Conclusion: Despite unfavorable pharmacokinetic properties as in the representative case studied here, there is an overall advantage to be gained in the safety profile of a chemotherapeutic agent via photocontrol. Nevertheless, optimization of the pharmacokinetic parameters of photoisomers is an important issue to be addressed during the development of photopharmacological drugs.

scholarly journals Neuroprotective Effect of Optimized Yinxieling Formula in 6-OHDA-Induced Chronic Model of Parkinson’s Disease through the Inflammation Pathway

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Renrong Wei ◽  
Cuiping Rong ◽  
Qingfeng Xie ◽  
Shouhai Wu ◽  
Yuchao Feng ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Calcium Binding ◽  
Dopaminergic Neurons ◽  
Neuroprotective Effect ◽  
Interleukin 1 ◽  
Mrna Levels ◽  
Cox 2

Parkinson’s disease (PD) is characterized by progressive degeneration of dopaminergic neurons in the substantia nigra (SN)-striatum circuit, which is associated with glial activation and consequent chronic neuroinflammation. Optimized Yinxieling Formula (OYF) is a Chinese medicine that exerts therapeutical effect and antiinflammation property on psoriasis. Our previous study has proven that pretreatment with OYF could regulate glia-mediated inflammation in an acute mouse model of PD induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Given that PD is a chronic degeneration disorder, this study applied another PD animal model induced by striatal injection of 6-hydroxydopamine (6-OHDA) to mimic the progressive damage of the SN-striatum dopamine system in rats. The OYF was administrated in the manner of pretreatment plus treatment. The effects of the OYF on motor behaviors were assessed with the apomorphine-induced rotation test and adjusting steps test. To confirm the effect of OYF on dopaminergic neurons and glia activation in this model, we analyzed the expression of tyrosine hydroxylase (TH) and glia markers, ionized calcium-binding adapter molecule 1 (Iba-1), and glial fibrillary acidic protein (GFAP) in the SN region of the rat PD model. Inflammation-associated factors, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), were further evaluated in this model and in interferon-γ- (INF-γ-) induced murine macrophages RAW264.7 cells. The results from the in vivo study showed that OYF reversed the motor behavioral dysfunction in 6-OHDA-induced PD rats, upregulated the TH expression, decreased the immunoreactivity of Iba-1 and GFAP, and downregulated the mRNA levels of TNF-α and COX-2. The OYF also trended to decrease the mRNA levels of IL-1β and iNOS in vivo. The results from the in vitro study showed that OYF significantly decreased the mRNA levels of TNF-α, IL-1β, IL-6, iNOS, and COX-2. Therefore, this study suggests that OYF exerts antiinflammatory effects, which might be related to the protection of dopaminergic neurons in 6-OHDA-induced chronic neurotoxicity.

scholarly journals Dissemination of Rat Cytomegalovirus through Infected Granulocytes and Monocytes In Vitro and In Vivo

2003 ◽  
Vol 77 (20) ◽  
pp. 11274-11278 ◽  
Author(s):  
B. W. A. van der Strate ◽  
J. L. Hillebrands ◽  
S. S. Lycklama à Nijeholt ◽  
L. Beljaars ◽  
C. A. Bruggeman ◽  
...  
Keyword(s):  
Intravenous Injection ◽  
Systemic Infection ◽  
Insight Into

ABSTRACT The role of leukocytes in the in vivo dissemination of cytomegalovirus was studied in this experiment. Rat cytomegalovirus (RCMV) could be transferred to rat granulocytes and monocytes by cocultivation with RCMV-infected fibroblasts in vitro. Intravenous injection of purified infected granulocytes or monocytes resulted in a systemic infection in rats, indicating that our model is a powerful tool to gain further insight into CMV dissemination and the development of new antivirals.

scholarly journals SBA1 Encodes a Yeast Hsp90 Cochaperone That Is Homologous to Vertebrate p23 Proteins

1998 ◽  
Vol 18 (7) ◽  
pp. 3727-3734 ◽  
Author(s):  
Yifang Fang ◽  
Albert E. Fliss ◽  
Jie Rao ◽  
Avrom J. Caplan
Keyword(s):  
Hormone Receptors ◽  
Pcr Amplification ◽  
Steroid Hormone Receptors ◽  
Loss Of Function ◽  
Vitro Assay ◽  
Growth Defects ◽  
Double Deletion ◽  
Affinity Isolation

ABSTRACT The Saccharomyces cerevisiae SBA1 gene was cloned by PCR amplification from yeast genomic DNA following its identification as encoding an ortholog of human p23, an Hsp90 cochaperone. TheSBA1 gene product is constitutively expressed and nonessential, although a disruption mutant grew more slowly than the wild type at both 18 and 37°C. A double deletion of SBA1and STI1, encoding an Hsp90 cochaperone, displayed synthetic growth defects. Affinity isolation of histidine-tagged Sba1p (Sba1His6) after expression in yeast led to coisolation of Hsp90 and the cyclophilin homolog Cpr6. Using an in vitro assembly assay, purified Sba1His6 bound to Hsp90 only in the presence of adenosine 5′-O-(3-thiotriphosphate) or adenyl-imidodiphosphate. Furthermore, interaction between purified Sba1His6 and Hsp90 in yeast extracts was inhibited by the benzoquinoid ansamycins geldanamycin and macbecin. The in vitro assay was also used to identify residues in Hsp90 that are important for complex formation with Sba1His6, and residues in both the N-terminal nucleotide binding domain and C-terminal half were characterized. In vivo analysis of known Hsp90 substrate proteins revealed that Sba1 loss of function had only a mild effect on the activity of the tyrosine kinase v-Src and steroid hormone receptors.

scholarly journals Bioinspired organometallic chemistry

2002 ◽  
Vol 74 (1) ◽  
pp. 115-122 ◽  
Author(s):  
Lanny S. Liebeskind ◽  
Jiri Srogl ◽  
Cecile Savarin ◽  
Concepcion Polanco
Keyword(s):  
Organometallic Chemistry ◽  
Refractory Metal ◽  
Redox Active ◽  
The Stability ◽  
New Procedures ◽  
Sulfur Containing ◽  
Insight Into

Given the stability of the bond between a mercaptide ligand and various redox-active metals, it is of interest that Nature has evolved significant metalloenzymatic processes that involve key interactions of sulfur-containing functionalities with metals such as Ni, Co, Cu, and Fe. From a chemical perspective, it is striking that these metals can function as robust biocatalysts in vivo, even though they are often "poisoned" as catalysts in vitro through formation of refractory metal thiolates. Insight into the nature of this chemical discrepancy is under study in order to open new procedures in synthetic organic and organometallic chemistry.

scholarly journals Microtubule Actin Cross-Linking Factor (Macf)

1999 ◽  
Vol 147 (6) ◽  
pp. 1275-1286 ◽  
Author(s):  
Conrad L. Leung ◽  
Dongming Sun ◽  
Min Zheng ◽  
David R. Knowles ◽  
Ronald K.H. Liem
Keyword(s):  
Calcium Binding ◽  
Coiled Coil ◽  
Specific Protein ◽  
Binding Domain ◽  
Full Length ◽  
Actin Binding ◽  
Cross Linking ◽  
Actin Binding Domain

We cloned and characterized a full-length cDNA of mouse actin cross-linking family 7 (mACF7) by sequential rapid amplification of cDNA ends–PCR. The completed mACF7 cDNA is 17 kb and codes for a 608-kD protein. The closest relative of mACF7 is the Drosophila protein Kakapo, which shares similar architecture with mACF7. mACF7 contains a putative actin-binding domain and a plakin-like domain that are highly homologous to dystonin (BPAG1-n) at its NH2 terminus. However, unlike dystonin, mACF7 does not contain a coiled–coil rod domain; instead, the rod domain of mACF7 is made up of 23 dystrophin-like spectrin repeats. At its COOH terminus, mACF7 contains two putative EF-hand calcium-binding motifs and a segment homologous to the growth arrest–specific protein, Gas2. In this paper, we demonstrate that the NH2-terminal actin-binding domain of mACF7 is functional both in vivo and in vitro. More importantly, we found that the COOH-terminal domain of mACF7 interacts with and stabilizes microtubules. In transfected cells full-length mACF7 can associate not only with actin but also with microtubules. Hence, we suggest a modified name: MACF (microtubule actin cross-linking factor). The properties of MACF are consistent with the observation that mutations in kakapo cause disorganization of microtubules in epidermal muscle attachment cells and some sensory neurons.

Abstract 3653: Akt3 Offers Stronger Protection than Akt1 Against Brain Injury by Differentially Promoting Mtor Protein Levels In Both In Vitro and In Vivo Stroke Models

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Rong Xie ◽  
Michelle Cheng ◽  
Mei Li ◽  
Robert Sapolsky ◽  
Heng Zhao
Keyword(s):  
Gene Transfer ◽  
Western Blotting ◽  
Ischemic Injury ◽  
Akt Pathway ◽  
Over Expression ◽  
Protein Levels ◽  
Akt Isoforms ◽  
The Brain

Background and Objective: Akt is a serine-threonine kinase that plays critical role in promoting cell survival. Akt consists of three isoforms (Akt1, 2, 3), with Akt3 predominantly expressed in the brain. Although Akt pathway has been shown to mediate neuronal survival in cerebral ischemic injury, it is unclear how these Akt isoforms contribute to neuronal protection, and whether exogenous Akt can protect the brain against ischemic injury or not. In this study, we over-expressed Akt isoforms and its downstream signaling proteins such as FKHR and PRAS40 to investigate the role of the Akt pathway along with its potential relationship with the mTOR pathway in stroke. Methods: Sprauge Dawley rats (250∼280g) were used for all studies. A lentiviral vector consists of a CMV promoter driving IRES-eGFP was used to clone an active Akt 1 and 3 (cAKt 1 and 3), dominant-negative Akt (AktDN), active FKHR (AAA FKHR), and PRAS40. Lentivirus expressing these genes were added to primary mixed cortical cultures for two days prior to oxygen glucose deprivation (OGD) (MOI=1:5). Neuronal survival was measured by LDH release. Lentivirus were stereotaxically injected into the cortex, and rats were subjected to focal ischemia induced by distal MCA occlusion combined with bilateral CCA occlusion. Western blotting and immunofluorescent confocal microscopy were used to detect the expression of Akt isoforms and other proteins in both the Akt and mTOR pathways. Results: Western blotting analysis showed that both endogenous Akt1 and 3 proteins degraded as early as 1 h after stroke, while Akt2 protein remained unchanged until 24 h after stroke. In vitro studies showed that over-expression of both constitutively active cAkt1 and cAkt3 decreased LDH release after OGD, while AktDN worsened neuronal death ( P <0.05). In vivo over-expression of cAkt1, cAkt3 and PRAS40 reduced infarct size after stroke ( P <0.01). Gene transfer of cAkt1 and 3 also promoted protein levels of pAkt (phosphorylated Akt), pPRAS40, pFKHR, pPTEN, pmTOR, but not pGSK3β. Both in vitro and in vivo studies showed that over-expression of cAkt3 resulted in a stronger protection than cAkt1 ( P <0.05). Interestingly, cAkt3 gene transfer preserved both endogenous protein levels of Akt1 and 3, whereas cAkt1 gene transfer only preserved endogenous Akt1. Furthermore, cAkt3 promoted higher pmTOR levels than cAkt1. Treatment of rapamycin, an mTOR inhibitor, blocked the protective effects of both cAkt1 and cAkt3 both in vitro and in vivo. Conclusion: Lentiviral-mediated overexpression of cAkt3 confers stronger protection than that of cAkt1, by maintaining both endogenous Akt1 and Akt3, as well as promoting higher mTOR activities after stroke.

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