Upload
dinhdieu
View
219
Download
3
Embed Size (px)
Citation preview
Roel Schins
IUF - Leibniz Research Institute for
Environmental Medicine, Dusseldorf
Bijeenkomst CGC & NVT-AT; Den Bosch, 14-3-2013
Stofdeeltjes:
Toxicokinetiek & -dynamiek
Dust (matter),
particles,
fine particulate matter (PM)
Poussière (matière),
particules,
particules fines
Stof (materie),
deeltjes, fijnstof
Staub (Materie/Stoff),
Teilchen/Partikel,
Feinstaub
http://geodata.rivm.nl/gcn/
(2011)
AMBIENT EXPOSURE
(PM10/PM2.5)
Adverse effects in susceptible groups:
Asthma attacks, exacerbations of COPD
and cardiovascular disease
Immunological effects
Cancer
(Diabetes, Alzheimer‘s disease…?)
Typical exposures: g/m3 Typical exposures: mg/m3
OCCUPATIONAL EXPOSURE
Pneumonitis
Chronic obstructive pulmonary
disease (COPD):
emphysema
chronic bronchitis
Pneumoconioses
(silicosis, asbestosis,..)
Lung cancer
Clearance via the muco-ciliary escalator
Deposition on the
conducting airways
Bronchial epithelium
Courtesy: Ken Donaldson/Peter Gehr
alveolar space
alveolar septum
capillary
red blood cell
alveolar space
alveolar septum
capillary
red blood cell
Clearance by alveolar
macrophage phagocytosis
Deposition on the
terminal bronchioles/
proximal alveoli
Interstitial
pathway via
lymph to the
lymph nodes
Clearance mechanisms of particles
Group Treatment Tumour (%)
Control Room air 3
Quartz 1 mg/m3 DQ12 6 h/day 5 days/week 24 months 19
Muhle et al. 1989 Am J Ind Hyg
Silica and cancer - toxicological evidence
(inhalation studies in rats)
0
2
4
6
8
10
12
14
16
18
20
0 20 40 60 80
Days exposure
Bronchoalveolar
Lavage neutrophils
(x106)
Donaldson et al. 1988 Thorax
Silica and inflammation: toxicological evidence Inflammatory effects of inhaling 10 mg/m3 quartz in rats
Exposure 7 h/day
5 days/week for
up to 75 days
Macrophage
Alveolus
Neutrophils
Lung epithelial
cell
Toxicology of inhaled particles
Exposure chronic inflammation fibrosis, cancer
alveolar space
alveolar septum
capillary
red blood cell
alveolar space
alveolar septum
capillary
red blood cell
epithelium
O2.-/H2O2
Recruitment of
inflammatory cells: Macrophages,
Polymorphonuclear
Neutrophils(PMN)
NFB
O2.-/H2O2
Oxidative damage
(proteins, lipids, DNA)
Proliferation
H2O2 .OH
O2.-/H2O2
Modified from: Stone, Johnson and Schins (2009) Crit Rev Toxicol
Reactive oxygen species generation (ROS) and
induction of “oxidative stress”
Phospho-IB
(Ser32/36)
μφ
Quartz (2mg i.t.)
NF-κB RelA
Epithelial type II cells
Epithelial type II cells
μφ
Control
Oxidative stress and NFB pathway activation
Cytosol
iNOS, COX-2, TNFα,
IL-1β, IL-6, IL-8 / MIP-2,
GM-CSF, ICAM-1, etc.
NucleusRelA
p50
RelA
p50
IκBαRelA
p50
RelA
p50
IKKγ
IKKα
IKKβ
26S
β-TrCP
IκBα
IκBα
P
U
IKKγ
Cytosol
iNOS, COX-2, TNFα,
IL-1β, IL-6, IL-8 / MIP-2,
GM-CSF, ICAM-1, etc.
NucleusRelA
p50
RelA
p50
RelA
p50
IκBαIκBαRelA
p50
RelA
p50
RelA
p50
RelA
p50
IKKγIKKγ
IKKα
IKKβ
26S
β-TrCP
IκBαIκBα
IκBαIκBα
P
UU
IKKγIKKγ
Van Berlo et al. (2010) Part Fibre Toxicol
Oxidative stress
NFB
activation
Cytokines/
chemokines
Phagocyte activation
(inflammation)
ROS production
Antioxidant
depletion
Oxidative stress and inflammation
Coutesy: Aalt Bast
Borm et al. (2004) Toxicol Appl Pharmacol
Carcinogenicity studies with particles in the rat
Tumour formation in rat inhalation bioassays is associated
with durability of the material (biopersistence)
Genotoxicity tests with epithelial cells
(HPRT, Micronuclei, strand breaks)
Percoll gradient
epithelial cells
surfactant
Purification
Harvesting
& Analysis
Trypsin
Digestion
Genotoxicity of poorly soluble particles in vivo (inhalation or intratracheal instillation of particles in rat models)
Lavage, isolation
Bronchoalveolar lavage fluid analysis
(inflammatory cell counts, toxicity)
Driscoll et al. 1997; Knaapen et al. 2002; De Boeck et al. 2004; Muller et al., 2008; Albrecht et al., 2009
0
50
100
150
200
0 20 40 60 80
% neutrophils in BAL
HP
RT
/10
e6 c
ells
TiO2
Carbon Black (NP)
Quartz
Intratracheal instillation of particles
Isolation of type II lung epithelial cells
(15 months after i.t. application)
Cell culturing for selection of HPRT-
mutants (i.e. growth in 6-thioguanine
containing medium)
Driscoll et al. (1997) Carcinogenesis
Mutagenesis in rat lungs is associated with severity and
persistence of pulmonary inflammation
Chronic inflammation and release of reactive
oxygen and nitrogen species (ROS/RNS)
Genotoxicity proliferation
Tumour formation
Particle exposure
apoptosis
cell cycle arrests
DNA repair
Schins and Knaapen (2007) Inhal Toxicol
secondary
primary
Primary vs. secondary genotoxicity of particles
0 200 400 600 800 0
0.5
1
1.5
2
2.5
3
Particle surface area (cm 2 ) N
um
ber
of
PM
Ns
(x
10
6 )
Burden expressed as surface area
TiO2 and
BaSO4
75mg/m3 BaSO4
50mg/m3 BaSO4
0 2 4 6 8 10 12 0
0.5
1
1.5
2
2.5
3
Lung burden (mg)
Nu
mb
er o
f P
MN
s (
x1
0 6
)
Burden expressed as mass
TiO2
BaSO4
50mg/m3 TiO2
25mg/m3 TiO2
Tran et al, 2000 Inhal Toxicol
Poorly soluble low toxicity particles
(PSP) Threshold of overload = 200-300
cm2 of particle surface in the rat lung
Chronic inflammation and lung burden of TiO2 and BaSO4
Aeroallergen Metal Salt
Non-toxic
particles
Soot
“Combustion derived
nanoparticles“
The PM mixture
Van Berlo et al EXS 2012
Extraction of PM from inert filters
(e.g. Teflon)
Human studies Rodent toxicology Cell culture Cell free assays
Sampling
of PM
Using PM samples in toxicology studies
Van Berlo et al EXS 2012
3.7 ± 2.7 4.6 ± 2.4 5.6 ± 3.0 * 4.6 ± 3.0 TNF
8.8 ± 2.4 14.7 ± 14.4 14.2 ± 5.2 * 8.6 ± 2.2 IL-6
Saline Zerbst Hettstedt Baseline
% Neutrophils 3.2 ± 3.6 3.7 ± 4.6 6.2 ± 7.1 1.2 ± 1.2
Control
(Saline)
PM2.5
Hettstedt
(Metal-rich)
PM2.5
Zerbst
Baseline
lavage
Lavage at t=24 h
Segmental instillation of “Hettstedt”- and
“Zerbst”- PM2.5 in human volunteers
Schaumann et al (2004) Am J Respir Crit Care Med
% Monocytes (FACS)
Baseline Saline H Z 0.0
2.5
5.0
7.5
10.0 Baseline Saline H Z %
p=0.02 p=0.01
% Monocytes (BAL)
**
*
********
********
0
1
2
3
4
3 - 7 µm 1.5 - 3 µm 0.95 - 1.5 µm 0.5 - 0.95 µm < 0.5 µm
Lo
g E
SR
(a.u
.)
RB
UB
BR
QR
Queensway underpass (A38),
Birmingham, UK
Mace Head Research station,
Connemara, Ireland (west coast)
OXIDANT GENERATION AND TOXICITY OF SIZE-FRACTIONATED
AMBIENT PARTICLES IN HUMAN LUNG EPITHELIAL CELLS.
RB = Remote background
UB = Urban background
BR = Bristol Road
QR = Tunnel
PM (size fraction)
DMPO
Wessels et al (2010) Environ Sci Technol
r = 0.70
p < 0.001
n = 44
0
10
20
30
40
50
60
0 1 2 3 4
Log ESR (a.u.)
Ox
ida
tiv
e D
NA
da
ma
ge
(a
.u.)
*
*
0
100
200
300
400
3 - 7 µm 1.5 - 3 µm 0.95 - 1.5 µm 0.5 - 0.95 µm < 0.5 µm
IL-8
(%
co
ntr
ol)
RB
UB
BR
QR
*
***
# #
***
0
10
20
30
40
50
60
3 - 7 µm 1.5 - 3 µm 0.95 - 1.5 µm 0.5 - 0.95 µm < 0.5 µm
Oxid
ati
ve D
NA
dam
ag
e (
a.u
.)
RB
UB
BR
QR
Oxidative DNA damage (A549 cells)
Oxidant generation / DNA damage
Interleukin-8 release (A549 cells)
Wessels et al (2010) Environ Sci Technol
Air
Respiratory
tract
Mucociliar clearance
Gastrointestinal
tract
Faeces
Particle effects beyond the respiratory tract
lymph
Liver
blood
brain
blood blood
Gehirn
Blut blood
brain
blood blood Brain
Blood
Kidney Urine
Inhaled ultrafine particles / nanoparticles
Food, water
ingestion
Dermal exposure Drug delivery
skin
Modified from Oberdorster et al EHP 2005
Summary
Particles can trigger oxidative stress and activation of NFB
signalling activation of the innate immune system
(macrophages, neutrophils)
Particle properties (e.g. surface reactivity, solubility) drive
inflammation (level and persistence)
Tumourigenesis in rat lungs by poorly soluble particles of low
toxicity (PSP) is driven by the “overload” phenomenon
(saturation due to macrophage clearance impairment)
Dose metrics other than mass should be considered:
surface area dose, number dose, surface reactivity
http://conference.iuf-duesseldorf.com/
Email: [email protected]
SCIENTIFIC COMMITTEE
Vicki Stone (Edinburgh) & Roel Schins (Düsseldorf)
SCIENTIFIC COMMITTEE
Paul Borm (Netherlands); Ken Donaldson (UK); Flemming Cassee (Netherlands); Vincent Castranova (USA); Bice Fubini (Italy); Mary Gulumian (South Africa); Marie-Claude Jaurand (France); Wolfgang Kreyling (Germany); Jean Krutmann (Germany); Dominique Lison (Belgium); Brooke Mossman (USA); Gunter Oberdörster (USA); Lang Tran (UK); Håkan Wallin (Denmark); David Warheit (USA)
MAIN TOPICS
• Toxicological testing and material/exposure characterization
• Target specific effects including respiratory tract, cardiovascular system, gastrointestinal tract, liver, central nervous system and reproductive organs
• Safe design of nanomaterials through hazard testing, modelling and QSAR type approaches
• Relating hazard study design and interpretation to regulatory requirements
Materials to be covered include crystalline silica, asbestos, environmental particulate matter, engineered nanomaterials as well as pharmaceutical particles.