Related Experiment Video
Updated: May 23, 2025
Vasodilation of Isolated Vessels and the Isolation of the Extracellular Matrix of Tight-skin Mice
Published on: March 24, 2017
Sensitivity Analysis to Isolate the Effects of Proteases and Protease Inhibitors on Extracellular Matrix Turnover
Amirreza Yeganegi1, Karla Robles1, William J Richardson2
1Department of Bioengineering, Clemson University, Clemson, SC.
Abstract:
Matrix metalloproteinases (MMPs) are a family of proteases that drive degradation of extracellular matrix (ECM) across many tissues. MMP activity is antagonized by tissue inhibitors of metalloproteinases (TIMPs), resulting in a complex multivariate system with many MMP isoforms and TIMP isoforms interacting across a network of biochemical reactions - each with their own distinct kinetic rates. This system complexity makes it very difficult to identify which specific molecules are most responsible for driving ECM turnover in vivo and therefore the most promising therapeutic targets. To help elucidate the specific roles of various MMP and TIMP isoforms, we present a computational systems biology model of collagen turnover capturing all possible interactions between type I collagen, four different MMP isoforms (MMP-1, -2, -8, and -9), and three different TIMP isoforms (TIMP-1, -2, and -4). We used dye-quenched fluorescent collagen to monitor the degradation of collagen in the presence of various MMP+TIMP cocktails, and we then used these experimental data to fit hypothetical reaction system topologies in order to investigate their respective accuracies. We determined kinetic rate constants for this system and used post-myocardial infarct time courses of collagen, MMP, and TIMP levels to perform a parameter sensitivity analysis across the model reaction rates and predict which molecules and interactions are the important regulators of ECM in the infarcted heart. Notably, the model suggested that MMP degradation and inactivation terms were more important for driving collagen levels than TIMP interaction terms. In sum, this work highlights the need for systems-level analyses to distinguish the roles of various biomolecules operating with a complex system, prioritizes therapeutic targets for post-infarct cardiac remodeling, and presents a computational framework that can be applied to many other collagen-rich tissues.
Insights
This study developed a computational model to understand how matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) affect collagen. The model identified MMP activity as a key driver of collagen turnover in the heart after injury.
Area of Science:
- Biochemistry
- Systems Biology
- Computational Biology
Background:
- Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) regulate extracellular matrix (ECM) turnover.
- The complex interactions between numerous MMP and TIMP isoforms make it challenging to pinpoint key regulators of ECM degradation in vivo.
- Identifying specific molecular targets is crucial for therapeutic interventions, particularly in conditions like post-myocardial infarction cardiac remodeling.
Purpose of the Study:
- To develop a computational systems biology model of collagen turnover.
- To elucidate the specific roles of various MMP and TIMP isoforms in ECM degradation.
- To identify key regulators of ECM turnover in the infarcted heart and prioritize therapeutic targets.
Main Methods:
- A computational systems biology model was created, encompassing interactions between type I collagen, four MMP isoforms (MMP-1, -2, -8, -9), and three TIMP isoforms (TIMP-1, -2, -4).
- Experimental data using dye-quenched fluorescent collagen monitored collagen degradation with various MMP+TIMP combinations.
- Kinetic rate constants were determined, and parameter sensitivity analysis was performed using post-myocardial infarct collagen, MMP, and TIMP levels.
Main Results:
- The computational model successfully captured interactions within the MMP-TIMP system.
- Experimental data were used to fit and validate hypothetical reaction system topologies.
- Parameter sensitivity analysis indicated that MMP degradation and inactivation were more critical for collagen levels than TIMP interactions in the infarcted heart.
Conclusions:
- Systems-level analysis is essential for distinguishing the roles of biomolecules in complex biological systems.
- The study prioritizes therapeutic targets for post-infarct cardiac remodeling by highlighting key MMP regulators.
- A computational framework was established for analyzing collagen-rich tissues and can be applied to other biological contexts.
More Related Videos
07:28Enrichment of Extracellular Matrix Proteins from Tissues and Digestion into Peptides for Mass Spectrometry Analysis
Published on: July 23, 2015
09:40A Rapid, Scalable Method for the Isolation, Functional Study, and Analysis of Cell-derived Extracellular Matrix
Published on: January 4, 2017
Related Concept Videos
01:23Role of Matrix Metalloproteases in Degradation of ECM
01:29The Extracellular Matrix
In order to maintain tissue organization, many animal cells are surrounded by structural molecules that make up the extracellular matrix (ECM). Together, the molecules in the ECM maintain the structural integrity of tissue as well as the remarkable specific properties of certain tissues.
Composition of the Extracellular Matrix
The extracellular matrix (ECM) is commonly composed of ground substance, a gel-like fluid, fibrous components, and many structurally and functionally diverse...
01:17Intracellular Signaling Affects Focal Adhesions
Some...