Hollow Gold Nanoparticals as Biocompatible Radiosensitizer: An In Vitro Proof of Concept Study

2015 ◽  
Vol 32 ◽  
pp. 106-112 ◽  
Author(s):  
Chien Wen Huang ◽  
Vasant Kearney ◽  
Sina Moeendarbari ◽  
Rui Qian Jiang ◽  
Preston Christensen ◽  
...  
Keyword(s):  
Small Animal ◽  
Intratumoral Injection ◽  
Culture Solution ◽  
Proof Of Concept ◽  
Normal Tissues ◽  
Concept Evaluation ◽  
A Cell ◽  
Clonogenic Cell ◽  
And Control

We report in vitro studies on radiotherapy enhancement of hollow gold nanoparticles (HAuNPs), which feature a 50 nm hollow core and a 30 nm thick polycrystalline shell. A clonogenic cell survival assay was used to assess radiation dose enhancement on breast cancer MDA-MB-231 cells. Cells were cultured in a cell culture solution in which pegylated HAuNPs were added. No cytotoxicity of the HAuNPs was observed at the nanoparticle concentration up to 4.25×109 nanoparticles/ml (350 μM Au concentration). A small animal X-ray irradiator and a clinical linear accelerator were used to irradiate HAuNP-treated and control groups. It shows that the radiation damage to the cells is significantly enhanced when the cells are exposed to HAuNPs. This is the first time that AuNPs with diameter larger than 100 nm has been studied for their radiosensitizing effects. In clinical settings, we envision that HAuNPs could be intratumorally injected into tumors, which is more realistic for practical usage of AuNPs as radiosensitizer than passive accumulation in tumors using the enhanced permeability and retention effect or active targeting. Larger particles are favored for the intratumoral injection approach since larger particles tend to be retained in the injection sites, less likely diffusing into surrounding normal tissues. So, this proof-of-concept evaluation shows a promising potential to use HAuNPs as radiation therapy sensitizer for cancers.

scholarly journals Ketone-body metabolism in tumour-bearing rats

1986 ◽  
Vol 233 (2) ◽  
pp. 485-491 ◽  
Author(s):  
A M Rofe ◽  
R Bais ◽  
R A Conyers
Keyword(s):  
Blood Glucose ◽  
Ketone Body ◽  
Ketone Bodies ◽  
Hepatic Glycogen ◽  
Turnover Rates ◽  
Total Blood ◽  
Normal Tissues ◽  
Tumour Bearing ◽  
And Control

During starvation for 72 h, tumour-bearing rats showed accelerated ketonaemia and marked ketonuria. Total blood [ketone bodies] were 8.53 mM and 3.34 mM in tumour-bearing and control (non-tumour-bearing) rats respectively (P less than 0.001). The [3-hydroxybutyrate]/[acetoacetate] ratio was 1.3 in the tumour-bearing rats, compared with 3.2 in the controls at 72 h (P less than 0.001). Blood [glucose] and hepatic [glycogen] were lower at the start of starvation in tumour-bearing rats, whereas plasma [non-esterified fatty acids] were not increased above those in the control rats during starvation. After functional hepatectomy, blood [acetoacetate], but not [3-hydroxybutyrate], decreased rapidly in tumour-bearing rats, whereas both ketone bodies decreased, and at a slower rate, in the control rats. Blood [glucose] decreased more rapidly in the hepatectomized control rats. Hepatocytes prepared from 72 h-starved tumour-bearing and control rats showed similar rates of ketogenesis from palmitate, and the distribution of [1-14C] palmitate between oxidation (ketone bodies and CO2) and esterification was also unaffected by tumour-bearing, as was the rate of gluconeogenesis from lactate. The carcinoma itself showed rapid rates of glycolysis and a poor ability to metabolize ketone bodies in vitro. The results are consistent with the peripheral, normal, tissues in tumour-bearing rats having increased ketone-body and decreased glucose metabolic turnover rates.

scholarly journals Effect of crotamine, a cell-penetrating peptide, on blastocyst production and gene expression of in vitro fertilized bovine embryos

Zygote ◽  
2014 ◽  
Vol 24 (1) ◽  
pp. 48-57 ◽  
Author(s):  
Iana S. Campelo ◽  
Alexsandra F. Pereira ◽  
Agostinho S. Alcântara-Neto ◽  
Natalia G. Canel ◽  
Joanna M.G. Souza-Fabjan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Control Group ◽  
Cell Penetrating Peptide ◽  
Mrna Levels ◽  
Bovine Embryos ◽  
Control Groups ◽  
Cell Penetrating ◽  
A Cell ◽  
And Control

SummaryThe present study investigated the effects of crotamine, a cell-penetrating peptide from rattlesnake venom, at different exposure times and concentrations, on both developmental competence and gene expression (ATP1A1, AQP3, GLUT1 and GLUT3) of in vitro fertilized (IVF) bovine embryos. In Experiment 1, presumptive zygotes were exposed to 0.1 μM crotamine for 6, 12 or 24 h and control groups (vehicle and IVF) were included. In Experiment 2, presumptive zygotes were exposed to 0 (vehicle), 0.1, 1 and 10 μM crotamine for 24 h. Additionally, to visualize crotamine uptake, embryos were exposed to rhodamine B-labelled crotamine and subjected to confocal microscopy. In Experiment 1, no difference (P > 0.05) was observed among different exposure times and control groups for cleavage and blastocyst rates and total cells number per blastocyst. Within each exposure time, mRNA levels were similar (P > 0.05) in embryos cultured with or without crotamine. In Experiment 2, concentrations as high as 10 μM crotamine did not affect (P > 0.05) the blastocyst rate. Crotamine at 0.1 and 10 μM did not alter mRNA levels when compared with the control (P > 0.05). Remarkably, only 1 μM crotamine decreased both ATP1A1 and AQP3 expression levels relative to the control group (P < 0.05). Also, it was possible to visualize the intracellular localization of crotamine. These results indicate that crotamine can translocate intact IVF bovine embryos and its application in the culture medium is possible at concentrations from 0.1–10 μM for 6–24 h.

scholarly journals Inhibition of Arenaviruses by Combinations of Orally Available Approved Drugs

2021 ◽  
Author(s):  
Shawn Herring ◽  
Jessica M. Oda ◽  
Jessica Wagoner ◽  
Delaney Kirchmeier ◽  
Aidan O’Connor ◽  
...  
Keyword(s):  
Virus Entry ◽  
Antiviral Drug ◽  
Lymphocytic Choriomeningitis ◽  
Neglected Diseases ◽  
Proof Of Concept ◽  
Effective Suppression ◽  
Resource Limited ◽  
Approved Drugs ◽  
And Control

Neglected diseases caused by arenaviruses such as Lassa (LASV) and filoviruses like Ebola (EBOV) primarily afflict resource-limited countries, where antiviral drug development is often minimal. Previous studies have shown that many approved drugs developed for other clinical indications inhibit EBOV and LASV and that combinations of these drugs provide synergistic suppression of EBOV, often by blocking discrete steps in virus entry. We hypothesize that repurposing combinations of orally administered approved drugs provides effective suppression of arenaviruses. In this report, we demonstrate that arbidol, an approved influenza antiviral previously shown to inhibit EBOV, LASV, and many other viruses, inhibits murine leukemia (MLV) reporter viruses pseudotyped with the fusion glycoproteins (GP) of other arenaviruses [Junin (JUNV), lymphocytic choriomeningitis virus (LCMV), and Pichinde (PICV)]. Arbidol and other approved drugs including aripiprazole, amodiaquine, sertraline, and niclosamide also inhibit infection of cells by infectious PICV, and arbidol, sertraline and niclosamide inhibit infectious LASV. Combining arbidol with aripiprazole or sertraline results in synergistic suppression of LASV and JUNV GP-bearing pseudoviruses. This proof-of-concept study shows that arenavirus infection in vitro can be synergistically inhibited by combinations of approved drugs. This approach may lead to a proactive strategy with which to prepare for and control known and new arenavirus outbreaks.

scholarly journals Clastogenic Effect of Atranorin, Evernic acid, and Usnic Acid on Human Lymphocytes

2014 ◽  
Vol 9 (4) ◽  
pp. 1934578X1400900 ◽  
Author(s):  
Gordana S. Stojanović ◽  
Miroslava Stanković ◽  
Igor Ž. Stojanović ◽  
Ivan Palić ◽  
Vesna Milovanović ◽  
...  
Keyword(s):  
Human Lymphocytes ◽  
Usnic Acid ◽  
Inhibitory Effect ◽  
Positive Control ◽  
Proliferation Index ◽  
Culture Solution ◽  
Antiproliferative Effects ◽  
Clastogenic Effect ◽  
And Control

Three lichen secondary metabolites atranorin (1), evernic acid (2), and usnic acid (3), were evaluated for their in vitro clastogenic and antiproliferative effects on human lymphocytes using the cytochalasin-B blocked micronucleus (CBMN) assay at concentrations of 2 μg/mL, 4 μg/mL and 6 μg/mL of final culture solution. The frequency of micronucleus (MN) was scored in binucleated cells, and cytokinesis-block proliferation index (CBPI) was calculated. Among the tested compounds, 3 exhibited the most prominent effect decreasing the frequency of MN in the range of 42.5% - 48.9%, that is about double of the positive control amifostin WR-2721 that reduces MN frequency for 22.0%. The effect of evernic acid was approximately equal to action of amifostin (23.2% −32.9%). Atranorin at concentrations of 2 μg/mL and 4 μg/mL decreasing the frequency of MN only for 11.1% and 1.8%, while in concentration of 6 μg/mL increases the frequency of MN for 9.6 %. The comparable CBPI values of the investigated compounds and control suggested that they did not show a statistically significant inhibitory effect on lymphocyte cell proliferation at applied concentrations.

scholarly journals Evaluation of Elastin-Like Polypeptides for Tumor Targeted Delivery of Doxorubicin to Glioblastoma

Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3242 ◽  
Author(s):  
Sonja Dragojevic ◽  
Rebecca Mackey ◽  
Drazen Raucher
Keyword(s):  
Targeted Delivery ◽  
Drug Carrier ◽  
In Vitro Cytotoxicity ◽  
Free Drug ◽  
Nuclear Accumulation ◽  
Therapeutic Approaches ◽  
Normal Tissues ◽  
C Terminus ◽  
A Cell

To increase treatment efficiency for glioblastoma, we have developed a system to selectively deliver chemotherapeutic doxorubicin (Dox) to Glioblastoma (GBM) tumors. This carrier is based on elastin-like polypeptide (ELP), which is soluble at physiological temperatures but undergoes a phase transition and accumulates at tumor sites with externally applied, mild (40–41 °C) hyperthermia. The CPP-ELP-Dox conjugate consists of a cell penetrating peptide (CPP), which facilitates transcytosis through the blood brain barrier and cell entry, and a 6-maleimidocaproyl hydrazone derivative of doxorubicin at the C-terminus of ELP. The acid-sensitive hydrazone linker ensures release of Dox in the lysosomes/endosomes after cellular uptake of the drug conjugate. We have shown that CPP-ELP-Dox effectively inhibits cell proliferation in three GBM cell lines. Both the free drug and CPP-ELP-Dox conjugate exhibited similar in vitro cytotoxicity, although their subcellular localization was considerably different. The Dox conjugate was mainly dispersed in the cytoplasm, while free drug had partial nuclear accumulation in addition to cytoplasmic distribution. The intracellular Dox concentration was increased in the CPP-ELP-Dox cells compared to that in the cells treated with free Dox, which positively correlates with cytotoxic activity. In summary, our findings demonstrate that CPP-ELP-Dox effectively kills GBM cells. Development of such a drug carrier has the potential to greatly improve current therapeutic approaches for GBM by increasing the specificity and efficacy of treatment and reducing cytotoxicity in normal tissues.

Phenethyl-4-ANPP: A Marginally Active Byproduct Suggesting a Switch in Illicit Fentanyl Synthesis Routes

2021 ◽  
Author(s):  
Marthe M Vandeputte ◽  
Alex J Krotulski ◽  
Fabian Hulpia ◽  
Serge Van Calenbergh ◽  
Christophe P Stove
Keyword(s):  
Valuable Insight ◽  
Unknown Compound ◽  
The Usa ◽  
A Cell ◽  
Synthesis Routes ◽  
And Control ◽  
First Time ◽  
Single Reaction

Abstract Profiling of the illicit fentanyl supply is invaluable from surveillance and intelligence perspectives. An important strategy includes the study of chemical attribution signatures (e.g., trace amounts of synthesis precursors, impurities/byproducts in seized material and metabolites in biological samples). This information provides valuable insight into the employed synthesis routes at the heart of illicit fentanyl manufacture (previously mainly the so-called Janssen or Siegfried methods), allowing to track and ultimately regulate crucial precursors. This report focuses on phenethyl-4-anilino-N-phenethylpiperidine (phenethyl-4-ANPP), a formerly unknown compound that was identified for the first time in a fentanyl powder sample seized in April 2019, followed by its identification in a biological sample in December 2019. Between 2019-Q4 and 2020-Q3, phenethyl-4-ANPP was detected in 25/1,054 fentanyl cases in the USA. There are currently no reports on how this compound may have ended up in illicit drug preparations and whether its presence may have potential in vivo relevance. We propose three possible fentanyl synthesis routes that, when badly executed in a single reaction vessel, may involve the formation of phenethyl-4-ANPP. We hypothesize that the presence of the latter is the result of a shift in fentanyl synthesis routes in an attempt to circumvent restrictions on previously used precursors. Using a cell-based µ-opioid receptor recruitment assay, we show that the extent of MOR activation caused by 100 µM phenethyl-4-ANPP is comparable to that exerted by a roughly 100,000-fold lower concentration of fentanyl (0.001 µM or 0.336 ng/mL). Negligible in vitro opioid activity, combined with its low abundance in fentanyl preparations, most likely renders phenethyl-4-ANPP biologically irrelevant in vivo. However, as clandestine operations are constantly changing shape, monitoring of fentanyl attributions remains pivotal in our understanding and control of illicit fentanyl manufacture and supply.

scholarly journals The IQGAP-related protein DGAP1 interacts with Rac and is involved in the modulation of the F-actin cytoskeleton and control of cell motility

1998 ◽  
Vol 111 (20) ◽  
pp. 3059-3071 ◽  
Author(s):  
J. Faix ◽  
C. Clougherty ◽  
A. Konzok ◽  
U. Mintert ◽  
J. Murphy ◽  
...  
Keyword(s):  
Actin Cytoskeleton ◽  
Cell Motility ◽  
Fluorescent Protein ◽  
Actin Dynamics ◽  
Cell Cortex ◽  
A Cell ◽  
Microfilament System ◽  
Green Fluorescent ◽  
And Control

DGAP1 of Dictyostelium discoideum is a cell cortex associated 95 kDa protein that shows homology to both RasGTPase-activating proteins (RasGAPs) and RasGAP-related proteins. When tested for RasGAP activity, recombinant DGAP1 protein did not promote the GTPase activity of human H-Ras or of Dictyostelium RasG in vitro. Instead, DGAP1 bound to Dictyostelium Rac1A and human Rac1, but not to human Cdc42. DGAP1 preferentially interacted with the activated GTP-bound forms of Rac1 and Rac1A, but did not affect the GTPase activities. Since Rho-type GTPases are implicated in the formation of specific F-actin structures and in the control of cell morphology, the microfilament system of mutants that either lack or overexpress DGAP1 has been analysed. DGAP1-null mutants showed elevated levels of F-actin that was organised in large leading edges, membrane ruffles or numerous large filopods. Expression of actin fused to green fluorescent protein (GFP) was used to monitor the actin dynamics in these cells, and revealed that the F-actin cytoskeleton of DGAP1-null cells was rapidly re-arranged to form ruffles and filopods. Conversely, in DGAP1-overexpressing cells, the formation of cellular projections containing F-actin was largely suppressed. Measurement of cell migration demonstrated that DGAP1 expression is inversely correlated with the speed of cell motility.

Ultrastructure of melanocyte-keratinocyte interactions and pigment transfer in vitro

1978 ◽  
Vol 36 (2) ◽  
pp. 650-651
Author(s):  
Raul I. Garcia ◽  
Evelyn A. Flynn ◽  
George Szabo
Keyword(s):  
Direct Injection ◽  
Skin Pigmentation ◽  
Freeze Fracture ◽  
Pigment Granule ◽  
Time Lapse ◽  
Ultrastructural Level ◽  
Lanthanum Tracer ◽  
A Cell

Skin pigmentation in mammals involves the interaction of epidermal melanocytes and keratinocytes in the structural and functional unit known as the Epidermal Melanin Unit. Melanocytes(M) synthesize melanin within specialized membrane-bound organelles, the melanosome or pigment granule. These are subsequently transferred by way of M dendrites to keratinocytes(K) by a mechanism still to be clearly defined. Three different, though not necessarily mutually exclusive, mechanisms of melanosome transfer have been proposed: cytophagocytosis by K of M dendrite tips containing melanosomes, direct injection of melanosomes into the K cytoplasm through a cell-to-cell pore or communicating channel formed by localized fusion of M and K cell membranes, release of melanosomes into the extracellular space(ECS) by exocytosis followed by K uptake using conventional phagocytosis. Variability in methods of transfer has been noted both in vivo and in vitro and there is evidence in support of each transfer mechanism. We Have previously studied M-K interactions in vitro using time-lapse cinemicrography and in vivo at the ultrastructural level using lanthanum tracer and freeze-fracture.

Using FRET to Measure the Time it Takes for a Cell to Destroy a Virus

2019 ◽  
Author(s):  
Candace E. Benjamin ◽  
Zhuo Chen ◽  
Olivia Brohlin ◽  
Hamilton Lee ◽  
Stefanie Boyd ◽  
...  
Keyword(s):  
Cellular Uptake ◽  
Rhodamine B ◽  
Virus Like Particle ◽  
A Cell ◽  
Viral Nanoparticles ◽  
The Stability ◽  
Open Question ◽  
Viral Surface ◽  
Fret Pair

<div><div><div><p>The emergence of viral nanotechnology over the preceding two decades has created a number of intellectually captivating possible translational applications; however, the in vitro fate of the viral nanoparticles in cells remains an open question. Herein, we investigate the stability and lifetime of virus-like particle (VLP) Qβ - a representative and popular VLP for several applications - following cellular uptake. By exploiting the available functional handles on the viral surface, we have orthogonally installed the known FRET pair, FITC and Rhodamine B, to gain insight of the particle’s behavior in vitro. Based on these data, we believe VLPs undergo aggregation in addition to the anticipated proteolysis within a few hours of cellular uptake.</p></div></div></div>

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