From Bioblast
Description
Abbreviation: NS(PGM)
Reference: A Β»Versions
- SUIT-category: NS(PGM)
- SUIT protocol pattern: diametral 1PM;2D;3G;4S;5U;6Rot
The SUIT-008 protocols are designed to assess the additivity between the N- and S-pathway in the Q-junction, providing a physiologically relevant estimate of maximum mitochondrial respiratory capacity. Also, serves as a diagnostic tool for the activity of the glutamate dehydrogenase and its linked pathway, which could be relevant in some pathologies. SUIT-008 can be easily extended with the CIV assay module.
Communicated by Cardoso LH, Doerrier C, Huete-Ortega M, Krumschnabel G and Gnaiger E (last update 2019-02-05)
Specific SUIT protocols
- SUIT-008 O2 pfi D014 for permeabilized fibers
- SUIT-008 O2 pce D025 for permeabilized cells
References
Year | Reference | Organism | Tissue;cell | |
---|---|---|---|---|
Lemieux 2017 Sci Rep | 2017 | Lemieux H, Blier PU, Gnaiger E (2017) Remodeling pathway control of mitochondrial respiratory capacity by temperature in mouse heart: electron flow through the Q-junction in permeabilized fibers. Sci Rep 7:2840. doi:10.1038/s41598-017-02789-8 | Mouse | Heart |
Steps and respiratory states
Step | State | Pathway | Q-junction | Comment - Events (E) and Marks (M) |
---|---|---|---|---|
1PM | PML(n) | N | CI | 1PM
|
2D | PMP | N | CI | 1PM;2D
|
2c | PMcP | N | CI | 1PM;2D;2c
|
3G | PGMP | N | CI | 1PM;2D;2c;3G
|
4S | PGMSP | NS | CI&II | 1PM;2D;2c;3G;4S
|
5U | PGMSE | NS | CI&II | 1PM;2D;2c;3G;4S;5U
|
6Rot | SE | S | CII | 1PM;2D;2c;3G;4S;5U;6Rot
|
7Ama | ROX | 1PM;2D;2c;3G;4S;5U;6Rot;7Ama
|
Step | Respiratory state | Pathway control | ET-Complex | Comment |
---|---|---|---|---|
## AsTm | AsTmE | CIV | CIV | |
## Azd | CHB |
- Bioblast links: SUIT protocols - >>>>>>> - Click on [Expand] or [Collapse] - >>>>>>>
- Coupling control
- Pathway control
- Β» Electron transfer pathway
- Β» Fatty acid oxidation pathway control state, F
- Β» NADH electron transfer-pathway state, N
- Β» Succinate pathway control state, S
- Β» NS-pathway control state, NS
- Β» Glycerophosphate pathway control state, Gp
- Β» Complex IV single step, CIV
- Β» Anaplerotic pathway control state
- Pathway control
- Main fuel substrates
- Β» Glutamate, G
- Β» Glycerophosphate, Gp
- Β» Malate, M
- Β» Octanoylcarnitine, Oct
- Β» Pyruvate, P
- Β» Succinate, S
- Main fuel substrates
- Glossary
Strengths and limitations
- + NS-OXPHOS capacity provides a physiologically relevant estimate of maximum mitochondrial respiratory capacity.
- + The presence of PGM and S establishes fully operative TCA cycle activity.
- + This protocol allows to analyse the convergence of pathways at the Q-junction (N, NS, S).
- + Mitochondrial external membrane integrity can be measured with the addition of cytochrome c. Application of the cytochrome c test early in the protocol ensures comparability of all states in case of any effect of c.
- + Reasonable duration of the experiment.
- + Complex IV activity can be measured.
- + GM and PM yield typically identical fluxes in human skeletal muscle fibres. However, PM is the superior alternative to GM: the fraction of the N-pathway is lower and of the S-pathway is higher with GM compared to PM (GMP is inhibited by the CII inhibitor malonic acid to a larger extent than PMP). PM, therefore, yields a more sensitive assay for the diagnosis of injuries in the N-pathway, since an impairment of N-pathway capacity can be compensated partially by activation of the S-pathway. This is an advantage compared to SUIT-011 for the diagnosis of N-capacity.
- - Fatty acid oxidation is not analysed.
- - When evaluating the additive effect of the N- and S-pathway, it has to be considered that NSP- and NSE-capacities can only be compared with NP- and SE-capacities. This is not a problem when NSP = NSE (Gnaiger 2009). In this case, it may be assumed that SP = SE (Votion et al 2012), such that NSP can be compared with NP + SP. SUIT-004 should be chosen for the additive effect in the ET-state.
- - Careful washing is required after the experiment to avoid carry-over of inhibitors and uncoupler.
Compare SUIT protocols
MitoPedia concepts: SUIT protocol, SUIT A, Recommended
MitoPedia methods:
Respirometry