welcome to mmig (mitochondria and metabolism interest group)
TRANSCRIPT
Welcome to MMIG
(Mitochondria and Metabolism Interest Group)
What is MMIG?
• Interest-driven group open to all PIs studying M & M, currently ~25 members
• Scientific exchange and collaboration
• Share resources and expertise
• Strengthen training environment
• Program development and visibility
Format
• Regular meetings: weekly, biweekly or monthly?
• Invited speakers/visitors (local and national): Monthly?
• Forum for the trainees (journal club and work-in-progress presentations)
• Annual retreat: November 8-9, 2010
• Home base: Mitochondria and Metabolism Center at SLU http://depts.washington.edu/mmcslu
• Program Specialist: Karen Liebert [email protected]– Refer new MMIG members– Suggest future meeting place– Suggest speakers, meeting time and frequency
gas-1
mev-1
clk-1
isp-1ctb-1
Mitochondrial Mutants
MMIG - 9 June 2010 - Morgan/Sedensky 1
Affected complex in kids?
EC50s for BIS=60
0
1
2
3
4
5
Mitochondrial Defects
% s
evo
flu
ran
e
complex I
non complex I
normal
MMIG - 9 June 2010 - Morgan/Sedensky 2
Respiratory Supercomplexes in C. elegans
Respiratory Supercomplexes in C. elegans
(Suthammarak et al, JBC 2008)MMIG - 9 June 2010 - Morgan/Sedensky 3
How is mitochondrial dynamics (fission/fusion) regulated in neurons?
Is the fission/fusion machinery in neurons unique?
How is mitochondrial fission/fusion regulated in neurons in response to injury and disease?
Can we prevent neuronal apoptosis and maintain function by modulating mitochondrial dynamics?
The complexities of regulating mitochondria in neurons
MMIG - 9 June 2010 - Morrison 1
MMIG - 9 June 2010 - Morrison 2
MMIG - 9 June 2010 - Morrison 3
Wang lab Research interests:
Physiological mitochondrial permeability transition pore (mPTP) opening
and superoxide flash activity in the heart;
Molecular mechanism of mPTP triggered superoxide flash production;
Role of mitochondrial reactive oxygen species (ROS) in oxidative stress.
What we do?
Focus on cardiovascular system;
Adult cardiac myocyte culture and adenovirus mediated gene transfer;
Confocal measurement of superoxide flash (cpYFP), mitochondrial /
cytosolic Ca2+ and mitochondrial membrane potential;
Assessment of cardiac myocyte function: contractility & Ca2+ handling;
Transgenic mice expressing superoxide indicator in mitochondria;
Mitochondrial ROS signaling in disease: ischemia reperfusion injury,
heart failure, diabetes and metabolic syndrome.MMIG - 9 June 2010 - Wang 1
Time (s)
488 nm
405 nm
0.3
F/F
0
10 s488 nm405 nm
10 m
Single Mitochondrial Superoxide Flash in Adult Cardiac Myocyte
(Wang et al, 2008, Cell 134:279-290)
TMRM
488 nm
405 nm
20 s
0.5 F
/F0
MMIG - 9 June 2010 - Wang 2
Integrative Study of Mitochondrial Function in Health & Disease
https://depts.washington.edu/mmcslu/homeMMIG - 9 June 2010 - Wang 3
Ca
Ca
Ca
CaCa
Ca
Ca Ca
Ca
IP3R
Ca
Ca
Ca
Ca
Ca
CaCa
Ca
Ca
Ca
Ca
Ca
Ca
Ca
Ca
Ca
Ca
Ca
PLC
IP3
Ca
Ca
Ca Ca
Ca Ca
m loss
Apoptosis
Ca
CaCa
Ca
Ca
Ca
CaCa
ROS
NF-
Inflammation
DAGPKC
Bioenergetics
TCA
How do mitochondria produce ROS?How are mitochondrial ROS ‘decoded’?
MMIG - 9 June 2010 - Hawkins 1
Relationship between cytosolic calcium and mitochondrial ROS ROS
MMIG - 9 June 2010 - Hawkins 2
Laboratory Interests• How do disparate mitochondrial calcium uptake patterns translate to cellular
function?
• How do calcium-linked oxidants influence mitochondrial function?
• What are the cellular targets of mitochondrial reactive oxygen species?
Microvascular EC
Macrovascular EC
MMIG - 9 June 2010 - Hawkins 3
Mitochondrial hub in apoptosis
Smart bombs
MMIG - 9 June 2010 - Hockenberry 1
Myc
Bcl-XL
Metabolic functions of oncogenes
MMIG - 9 June 2010 - Hockenberry 2
Hsp90 and proteasome - dependentdegradation of mitochondrial proteins(an ERAD-like pathway)
Mitochondrial graveyard or nurseryMMIG - 9 June 2010 - Hockenberry
3
ATP
PCr
MbO2
HbO2
PCr
ATP
Pi
ppm
NMROPTICS
500 600 700 8000.0
0.5
1.0
nm
oxy
deoxy
OPTICS
MMIG - 9 June 2010 - Marcinek 1
Less Efficient Mitochondria in Aged Muscle
Marcinek et al., 2005, J Physiol, 569Marcinek et al., 2005, J Physiol, 569
ATP
H+
O2 H2O
H+ H+
P/O
30-month7-month0
1
2
*
0
2
4
6
8
10
7 month 30 month
O2 consumption
0
10
20
30
7 month 30 month
*
ATP production
MMIG - 9 June 2010 - Marcinek 2
Control of Mitochondria by Oxidative Stress
2 wkPQ
7 moSOD1-/-
mTOR signaling, muscle atrophy, agingapoptosis, mitochondrial biogenesis
Implications:
MMIG - 9 June 2010 - Marcinek 3
HIV-related Fatigue and Mitochondrial Dysfunction related to Antiretroviral
Treatments
MMIG - 9 June 2010 - Voss 1
Projects1. Proteomic Biomarker Discovery in Plasma of HIV
Patients (Dave Goodlett, School of Pharmacy)2. Mitochondrial Function in skeletal muscle of men
with prostate cancer-related fatigue3. Mitochondrial Dysfunction and NRTI-treatment
effects in skeletal muscle of aging mice (Dave Marcinek, Peter Rabinovitch, School of Medicine)
4. Gene expression changes in skeletal muscle of aging mice receiving antiretroviral treatment for 8 weeks (Molecular Lab in the SON)
MMIG - 9 June 2010 - Voss 2
Preliminary ResultsInner mitochondrial membrane proteins in
the plasma of patients with HV-related fatigueSteroid hormone pathway is impacted by HIV
and ART treatmentPGC1α and Thymidine kinase 2 are affected
by AZT treatmentSignificant changes in ATP production with
AZT treatment
MMIG - 9 June 2010 - Voss 3
CLINICAL TRIALS - FDA THYROID HORMONE SUPPLEMENTATION IN
INFANTS UNDERGOING CARDIOPULMONARY BYPASS (FDA)
MULTI-SITE
RECRUITED 200 PATIENTS…
ONE OF THE LARGEST CLINICAL TRIALS EVER PERFORMED IN PEDIATRIC CARDIOLOGY/CARDIAC SURGERY
T3 SUPPLEMENTATION IMPROVED CLINICAL ENDPOINTS AND CARDIAC FUNCTION IN INFANTS MMIG - 9 June 2010 - Portman 1
MECHANISMS FOR CLINICAL RESPONSE: ANIMAL MODELS OF PEDIATRIC MECHANICAL-CIRCULATORY SUPPORT
Oxaloacetate
Citrate
Cis-aconitate
Isocitrate
-ketoglutarate
Succinyl-CoA
Succinate
Fumarate
Malate
glutamate
Glutamine
Acetyl-CoAPyruvateFatty Acids
Aspartate
Proprionyl-CoA
mTOR mTOR-Active
Phenylalanine
Isoleucine, Valine
ProteinAmino acids
CARDIAC FUNCTION
Leucine
FA- odd carbon
General scheme of integration between metabolism and protein synthesis studied in experimental plan
Alanine
T3NiOx
MMIG - 9 June 2010 - Portman 2
AGING
Dominant negative thyroid hormone receptor alters substrate metabolism with reduction in FFA flux
Aging in mice results in reduced FFA flux with decreased systolic function
T3 reduced in aging mouse modelTOTAL T3 (ng/dl)
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
YOUNG OLD
*
TOTAL T3 (ng/dl)
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
YOUNG OLD
*
Hypothesis - T3 treatment modifies substrate flux and restores cardiac function
MMIG - 9 June 2010 - Portman 3
• Cardiac metabolism and Energetics: • Modulating cardiac energy metabolism to improve cardiac
function during stresses – Transgenic mice and NMR • Mitochondrial Biogenesis and Function:
• Regulation of mitochondrial biogenesis in heart failure -- mtDNA replication
• Mechanistic link between mito dysfunction and the development of pathological hypertrophy
• Metabolic Signaling: • AMPK-activated Protein Kinase (AMPK): Signaling
cascade and isoform-specific roles of AMPK in the heart • Metabolites regulate cardiac biology: integrating
transcriptomics with metabolomics
Tian Lab studies the Heart
Tian MMIG - 9 June 2010 - Tian 1
Functional and Metabolic Phenotyping
13C NMR Spectroscop
y
Transgenic Mice
TAC or MI
In vivo Cardiac functio
n31P NMR
Spectroscopy
mixed substrates
5.5mM 1,6-13C GLU 0.4mM U-13C FA 1.2mM Lactate 50μU/ml Insulin
Langendorff Perfusions
NMR imaging + localized
spectroscopy
NMR imaging + localized
spectroscopy
Tian MMIG - 9 June 2010 - Tian 2
% oxidation of carbon substrate by 13C NMR
glucose
lactate
glucose
fatty acids
endo
ketones
lactate
WT
ketones
Dynamic changes of myocardial energetics and ATP synthesis in beating hearts by 31P NMR
fatty acids
endo
glucoselactate
ketones
PPAR-/-
glucose
fatty acids
endo
lactate
PPAR-/-GLUT1
ketones
P
i
Pi
PCr AT
P
M
∞
M
0
ADP + Pi ATP
Kfor =M0 - M∞
T1 M∞
Kfor x [Pi]Flux =
Tian MMIG - 9 June 2010 - Tian 3