scholarly journals Carbon Black Particle Exhibits Size Dependent Toxicity in Human Monocytes

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Devashri Sahu ◽  
G. M. Kannan ◽  
R. Vijayaraghavan
Keyword(s):  
Gene Expression ◽  
Carbon Black ◽  
Ultrafine Particles ◽  
Dna Analysis ◽  
Carbon Black Particle ◽  
Human Monocytes ◽  
Phagocytic Capacity ◽  
Monocyte Chemoattractant Protein 1 ◽  
Mortality And Morbidity ◽  
Micron Size

Increased levels of particulate air pollution are associated with increased respiratory and cardiovascular mortality and morbidity. Some epidemiologic and toxicological researches suggest ultrafine particles (<100 nm) to be more harmful per unit mass than larger particles. In the present study, the effect of particle size (nano and micro) of carbon black (CB) particle on viability, phagocytosis, cytokine induction, and DNA damage in human monocytes, THP-1 cells, was analysed. The cells were incubated with nanosize (~50 nm) and micron (~500 nm) size of CB particles in a concentration range of 50–800 µg/mL. The parameters like MTT assay, phagocytosis assay, ELISA, gene expression, and DNA analysis were studied. Exposure to nano- and micron-sized CB particles showed size- and concentration dependent decrease in cell viability and significant increase in proinflammatory cytokines IL-1β, TNF-αand IL-6 as well as chemokine IL-8 release. Gene expression study showed upregulation of monocyte chemoattractant protein-1 gene while cyclooxygenase-2 gene remained unaffected. Nano CB particles altered the phagocytic capacity of monocytes although micron CB had no significant effect. CB particles did not show any significant effect on DNA of monocytes. The investigations indicate that CB particles in nanosize exhibit higher propensity of inducing cytotoxicity, inflammation, and altered phagocytosis in human monocytes than their micron size.

scholarly journals Particulate Matter-Induced Acute Coronary Syndrome: MicroRNAs as Microregulators for Inflammatory Factors

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Nur Izah Ab Razak ◽  
Nor Eliani Ezani ◽  
Norzian Ismail
Keyword(s):  
Gene Expression ◽  
Air Pollution ◽  
Acute Coronary Syndrome ◽  
Particulate Matter ◽  
Ultrafine Particles ◽  
Inflammatory Factors ◽  
Potential Contribution ◽  
Mortality And Morbidity ◽  
Coronary Syndrome ◽  
Polycyclic Aromatic

The most prevalent cause of mortality and morbidity worldwide is acute coronary syndrome (ACS) and its consequences. Exposure to particulate matter (PM) from air pollution has been shown to impair both. Various plausible pathogenic mechanisms have been identified, including microRNAs (miRNAs), an epigenetic regulator for gene expression. Endogenous miRNAs, average 22-nucleotide RNAs (ribonucleic acid), regulate gene expression through mRNA cleavage or translation repression and can influence proinflammatory gene expression posttranscriptionally. However, little is known about miRNA responses to fine PM (PM2.5, PM10, ultrafine particles, black carbon, and polycyclic aromatic hydrocarbon) from air pollution and their potential contribution to cardiovascular consequences, including systemic inflammation regulation. For the past decades, microRNAs (miRNAs) have emerged as novel, prospective diagnostic and prognostic biomarkers in various illnesses, including ACS. We wanted to outline some of the most important studies in the field and address the possible utility of miRNAs in regulating particulate matter-induced ACS (PMIA) on inflammatory factors in this review.

Research on Electrical Double Percolation of Carbon Black-Filled Cement-Based Composites

2011 ◽  
Vol 311-313 ◽  
pp. 201-204
Author(s):  
Hong Zhong Ru ◽  
Ran Ran Zhao
Keyword(s):  
Carbon Black ◽  
Cement Paste ◽  
Volume Fraction ◽  
Carbon Black Particle ◽  
Carbon Black Content ◽  
Percolation Behavior ◽  
Key Factor ◽  
Binder Ratio ◽  
Black Particle ◽  
Double Percolation

Electrical conductive carbon black-filled cement-based composites are significant as multifunctional structural materials. Double percolation in carbon black-filled cement-based composites involves both carbon black particle percolation and cement paste percolation, which has great effect on the resistivity of composites. Based on double percolation theory, the influences of sand-binder ratio and carbon black volume fraction on the resistivity of carbon black-filled cement-based composites are investigated. The results show that besides carbon black volume fraction, sand-binder ratio is a key factor affecting double percolation behavior in carbon black-filled cement-based composites. At a fixed carbon black content in overall mortar, with increasing sand-binder ratio, the cement paste percolation though aggregate phase increases due to high obstruction of aggregate but the carbon black particle percolation in cement paste decreases. This is because that the microstructure of aggregate is impenetrable so that the carbon black particles are limited in cement paste, that is, the carbon black content in paste is compacted and large amount of conductive paths are generated by lapped adjacent carbon black particles in paste. The double percolation in the electrical conduction in carbon black-filled cement-based composites is observed when the carbon black volume fraction is 7.5% and sand-binder ratio is 1.4, and its resistivity is only 3200 Ωcm, so that a sand-binder ratio of 1.4 and 7.5% carbon black volume fraction or more are recommended for attaining high conductivity with a compromise between workability and conductivity.

scholarly journals Increased proinflammatory and oxidant gene expression in circulating mononuclear cells in older adults: amelioration by habitual exercise

2011 ◽  
Vol 43 (14) ◽  
pp. 895-902 ◽  
Author(s):  
Lindsey B. Gano ◽  
Anthony J. Donato ◽  
Gary L. Pierce ◽  
Hamza M. Pasha ◽  
Katherine A. Magerko ◽  
...  
Keyword(s):  
Gene Expression ◽  
Older Adults ◽  
Aerobic Exercise ◽  
Exercise Intervention ◽  
Mononuclear Cells ◽  
Maximal Oxygen Consumption ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Maximal Heart Rate ◽  
Peripheral Blood Mononuclear ◽  
Monocyte Chemoattractant Protein 1

We tested the hypothesis that peripheral blood mononuclear cells (PBMC) of older adults demonstrate a proinflammatory/-oxidative gene expression profile that can be improved by regular aerobic exercise. PBMC were isolated from young ( n = 25, 18–33 yr) and middle-aged/older ( n = 40, 50–76 yr) healthy adults. The older adults had greater mRNA expression (real-time RT-PCR) of the proinflammatory/-oxidant transcription factor nuclear factor-κB (1.58-fold, P < 0.05) and receptor for advanced glycation end products (1.12-fold, P < 0.05), the proinflammatory cytokines tumor necrosis factor-α (1.90-fold, P < 0.05) and monocyte chemoattractant protein-1 (1.47-fold, P < 0.05), and the oxidant-producing enzymes nicotinamide adenine dinucleotide phosphate-oxidase (0.91-fold, P < 0.05) and inducible nitric oxide synthase (2.60-fold, P < 0.05). In 11 subjects (58–70 yr), maximal oxygen consumption (+11%) and exercise time (+19%) were increased (both P < 0.001), and expression of the above proinflammatory/-oxidative genes was or tended to be decreased in PBMC after vs. before 2 mo of aerobic exercise (brisk walking ∼6 days/wk, 50 min/day, 70% of maximal heart rate). Expression of interleukin-6 was not different with age or exercise intervention. Age group- and exercise intervention-related differences in gene expression were independent of other factors. PBMC of healthy older adults demonstrate increased expression of several genes associated with inflammation and oxidative stress, which is largely ameliorated by habitual aerobic exercise. This proinflammatory/-oxidative gene signature may represent a therapeutic target for lifestyle and pharmacological prevention and treatment strategies.

scholarly journals Downregulation of c-fms gene expression in human monocytes treated with phorbol esters and colony-stimulating factor 1

Blood ◽  
1989 ◽  
Vol 74 (1) ◽  
pp. 123-129 ◽  
Author(s):  
E Sariban ◽  
K Imamura ◽  
M Sherman ◽  
V Rothwell ◽  
P Pantazis ◽  
...  
Keyword(s):  
Gene Expression ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Phorbol Esters ◽  
Constitutive Expression ◽  
Human Monocytes ◽  
Colony Stimulating Factor ◽  
Protein Levels ◽  
Kinase C ◽  
Stimulating Factor

Abstract The colony-stimulating factor-1 (CSF-1) regulates survival, growth, and differentiation of monocytes by binding to a single class of high- affinity receptors. The CSF-1 receptor is identical to the product of the c-fms protooncogene. The present studies monitored the effects of TPA and CSF-1 on c-fms gene expression in human monocytes. The results demonstrate that TPA downmodulates the constitutive expression of c-fms mRNA to low but detectable levels. Treatment of human monocytes with TPA was similarly associated with decreases in levels of the 138- and 125-Kd c-fms-encoded proteins. However, the kinetics of c-fms protein downmodulation indicated independent effects of TPA on c-fms expression at the RNA and protein levels. Furthermore, c-fms protein levels subsequently recovered despite persistently low levels of c-fms mRNA. Although previous studies demonstrated that c-fms protein is down- regulated in the presence of CSF-1, the present results indicate that CSF-1 also downregulates levels of c-fms mRNA. Moreover, the results indicate that CSF-1 increases protein kinase C activity in the membrane fraction. Together, these findings suggest that c-fms gene expression is differentially regulated at both the RNA and protein levels after activation of protein kinase C in human monocytes treated with TPA and CSF-1.

Sign in / Sign up

Export Citation Format

Share Document