Various roles of Cx43 in cardioprotection
Switzerland (swimsa) - University of Geneva, Geneva
Department of Pathology and Immunology
Prof. Brenda R. Kwak
Prof. Brenda R. Kwak
Required: English , Accepted: French
8 weeks
Cities/Months Jan Feb Mar Apr May Jun Jul Augt Sep Oct Nov Dec
No No Yes Yes Yes Yes No No Yes Yes Yes Yes
Type of Research Project
- Basic science
What is the background of the project?
Ischemic heart disease is the leading cause of mortality, accounting for about 15 million deaths each year. Thus, new treatments are needed to protect the heart against ischemia-reperfusion injury to prevent extensive cell death resulting in arrhythmias, diminished contractile function and heart failure. Despite intensive research, there are currently no effective cardioprotective therapies in clinical practice. Propagation of electrical signals in the heart depends on intercellular communication between cardiomyocytes through connexin43 (Cx43) gap junction channels. These structures also permit the cell-to-cell spread of molecules critical for cell death or survival. In the last few years, Cx43 has emerged as an important player in cardioprotection. Indeed, reducing Cx43 expression or inhibiting Cx43 channels improves the outcome of cardiac ischemia-reperfusion in animal models. However, it should be kept in mind that Cx43 is also expressed in non-cardiomyocyte cell populations of the heart, such as endothelial cells and fibroblasts, and their contribution to Cx43-mediated cardioprotection is at present not known.
What is the aim of the project?
This project aims at investigating how exposure to chronic hypoxia affects the non-canonical functions of Cx43 in cardiac endothelial cells and fibroblasts and how these changes might affect the outcome of cardiac ischemia-reperfusion.
What techniques and methods are used?
- First, we will make in vitro cell cultures and expose them to ischemia or hypoxia and reperfusion - We will then proceed to the cultivation and transfection of the cells - We will then extract Ribonucleic acid (RNA) and perform quantitative polymerase chain reaction (PCR) to amplify the specific sequences of interest - We will then proceed to immunofluorescent staining and microscopy to look for the microscopic patterns of Cx-43 - Furthermore, protein extraction and Western blotting will be performed to assess whether the cultured cells are immunoreactive to Cx43 - Finally, ex vivo Langendorff isolated heart perfusion will be done for detailed determination of cardiac function before, during and after ischemia/reperfusion -Data will be collected and analyzed using Prism or SPSS
What is the role of the student?
- The student will observe the practical experiments but will be highly involved in the analysis of the results
- The tasks will be done under supervision
What are the tasks expected to be accomplished by the student?
The student will closely follow the practical work and analyses of the Postdoc / PhD student involved in this project. In the following weeks, the student will be actively involved in the practical aspects of the experimental work on cells as well as in the analyses of these experiments, such as preparing slides and analyzing them with the mentor, quantifying and extracting data from immunohistochemical slides. The student will observe the ex vivo Langendorff experiments and will receive detailed explanations on the set-up and the cardiac function analyses, including the specific software that is used in the lab. Data analysis once the data has been collected can be expected to be done with Prism or SPSS. Prior knowledge of computer science (coding) or data analysis tools is valuable but not mandatory.
Will there be any theoretical teaching provided (preliminary readings, lectures, courses, seminars etc)
Yes, the student will have preliminary readings to perform which will be discussed in detail with the group leader (Brenda Kwak) and co-supervising Postdoc before the start of the experimental work. The student will also join the group’s weekly lab meetings during will he/she is expected to present the experiments. Furthermore, the student will have the opportunity to join departmental progress reports and seminars.
What is expected from the student at the end of the research exchange? What will be the general outcome of the student?
- The student will prepare a scientific report
What skills are required of the student? Is there any special knowledge or a certain level of studies needed?
Subjects passed: physiology, endocrinology
Are there any legal limitations in the student’s involvement
No direct involvement in animal experimentation
Type of students accepted
This project accepts:
- Medical students
- Students in biomedical fields
- Morel S; Christoffersen C; Axelsen LN; Montecucco F; Rochemont V; Frias MA; et al. Sphingosine-1-phosphate reduces ischaemia–reperfusion injury by phosphorylating the gap junction protein Connexin43. Cardiovasc Res. 2016 Mar 1;109(3):385–96.
- Morel S; Christoffersen C; Axelsen LN; Montecucco F; Rochemont V; Frias MA; et al. Sphingosine-1-phosphate reduces ischaemia–reperfusion injury by phosphorylating the gap junction protein Connexin43. Cardiovasc Res. 2016 Mar 1;109(3):385–96.
- Morel S; Braunersreuther V; Chanson M; Bouis D; Rochemont V; Foglia B; et al. Endothelial Cx40 limits myocardial ischaemia/reperfusion injury in mice. Cardiovascular Research. 2014 May 1;102(2):329–37.
- Leybaert L; Lampe PD; Dhein S; Kwak BR; Ferdinandy P; Beyer EC; et al. Connexins in Cardiovascular and Neurovascular Health and Disease: Pharmacological Implications. Levy FO; editor. Pharmacol Rev. 2017 Oct;69(4):396–478.