Chronic Heart Failure (CHF) is combined with various metabolic shifts. The continuous adrenergic stress results in a metabolic shift increasing glycolysis similar to a fetal metabolism. However also insulin resistance (IR) was reported triggering low glucose uptake
and mitochondrial uncoupling and therefore reactive oxygen species (ROS) production reduce cardiac contractility. The adrenergic increased free fatty acids (FFA) are metabolized to ketone bodies (mainly β-hydroxybutyrate (OHB)) which are also energy stocks for brain and heart. Elevated blood ketone levels have been reported during CHF similar to diabetes. Clinically a correlation between ketone body blood level and severity of CHF has been discovered. However it remains unclear whether this is a result of metabolic changes or a compensatory mechanism. The aim of this study was to show, that rat cardiomyocytes (H9c2) treated with Phenylephrine (PE) for hypertrophy are slightly more susceptible to OHB at concentrations similar found in patients with CHF and that OHB reduces cell area significantly.
Table of Contents
1. Introduction
1.1 Theoretical Background
1.1.1 Chronic Heart Failure
1.1.2 Mitochondrial Alterations
1.1.3 Metabolic Shift
1.1.4 Insulin Resistance
1.1.5 Ketone Bodies
1.1.6 Oxidative Stress
1.1.7 Microcurrent Therapy
1.2 Aim of this experiment
2. Results
2.1 Hypertrophic Model
2.1.1 H9c2
2.1.2 Primary cardiomyocytes (SHR7)
2.1.3 Electro Microcurrent treated primary (SHR7) cells
2.2 Cell growth under β-Hydroxybutyrate treatment
2.2.1 Cell proliferation Assay with alamarBlue®
2.2.2 Hypertrophic growth under β-Hydroxybutyrate treatment
2.3 ROS assay
2.4 Immunohistochemical staining (Mitochondrial distribution)
2.4.1 H9c2
2.4.2 SHR7
3. Discussion
3.1 Hypertrophic Model
3.2 Mitochondrial Activity Assay
3.3 ROS Assay
3.4 Immunostaining
4. Conclusion
5. References
6. Methods
6.1 Hypertrophic Model
6.2 Hypertrophic Measurement
6.3 HE-Staining
6.4 MitoTracker®
6.5 ROS-Measurement
6.6 OHB Proliferation Assay
6.7 AlamarBlue®-Assay
6.8 Cristal Violet-Assay
6.9 Immunohistochemical staining (Caveolin-3)
6.10 Immunohistochemical staining (α-Tubulin)
6.11 Microcurrent treatment of SHR7 cells
Research Objectives and Themes
This study investigates the metabolic and morphological influence of 3-hydroxybutyrate (OHB) and electrical microcurrent treatment on rat cardiomyocytes (H9c2 and SHR7) under conditions of simulated hypertrophy, specifically analyzing its impact on cell viability, hypertrophic growth, and mitochondrial distribution.
- Induction of cellular hypertrophy via Phenylephrine (PE).
- Effects of ketone bodies (OHB) on cardiomyocyte activity and cell size.
- Evaluation of microcurrent application as a potential therapeutic intervention.
- Assessment of mitochondrial dynamics and distribution using fluorescent imaging.
- Analysis of metabolic signaling pathways and their role in heart failure.
Excerpts from the Book
Ketone Bodies
Chronic elevated FFA levels also alters liver metabolisms which start converting FFA into ketone bodies (KB) namely β-Hydroxybutyrat (OHB) and Acetoacetat (AAc) (31). Some papers referred to KB as “superfuel” since it produces more energy per oxygen consumption than glucose or fatty acids, because concentrations of NADH increases relative to NAD+ and CoQ relative to CoQH2 accelerating the redox-reaction at the NADH dehydrogenase complex (32). This is also confirmed by a complex perfused rat heart preparation where OHB increased contractility and decreased oxygen consumption (33). Furthermore it was shown, that ketogenesis increased parallel with growing brain size, which only uses glucose and KB as energy source, during the evolution of vertebrates (34).
However, the highest part of KB’s myocardial oxygen consumption can be found within fetal organisms (e.g. not over 7% in lamb) (35). Normal individual blood levels are less than 0.1 mM for both OHB and AAc, but can reach up to 8 mM of OHB and 2 mM for AAc and Acetone (36). Clinical Studies carried out by Lommi et al. showed that patients suffering from CHF do have a 2-fold increase in blood KB in mean compared to control subjects. Additionally blood KB levels correlate with severity of symptoms, degrees of venous congestion, left ventricular dysfunction as well as neurohormonal activation (9).
Whereas previous studies assumed that KB block the citrate cycle (CC) (37) and thureupon cause contractility dysfunction (38) newer studies showed that KB prevent glucose uptake by inhibition of AMPK, generation of oxidative stress and promoting IR what might reduce cardiac energy substrate support in CHF (39). If the effect of KB is a negative one inhibition of carnitine palmitoyl transferase-1 (CPT-1) as most regulated step in ketogenesis may be a therapeutic possibility (40).
Summary of Chapters
Introduction: Provides a theoretical foundation by discussing the pathophysiology of Chronic Heart Failure, metabolic shifts, and current therapeutic hypotheses involving ketone bodies and microcurrent therapy.
Results: Details the empirical data gathered from establishing hypertrophic cell models and testing the effects of OHB and microcurrents on cell size and mitochondrial morphology.
Discussion: Interprets the experimental findings, specifically the reduction of hypertrophy by OHB and the limitations of the performed ROS assays, while contextualizing these results within current scientific literature.
Conclusion: Summarizes that adrenergic stimulation and metabolic factors are critical to CHF progression and highlights the potential of microcurrent applications as a therapeutic strategy.
Methods: Outlines the precise experimental protocols used, including cell culture conditions, staining procedures, and the application of electrical microcurrent devices.
Keywords
Chronic Heart Failure, Cardiomyocytes, 3-Hydroxybutyrate, Microcurrent Therapy, Hypertrophy, Phenylephrine, Mitochondria, Caveolin-3, Metabolic Shift, Ketone Bodies, Insulin Resistance, Reactive Oxygen Species, Cell Proliferation, H9c2, SHR7.
Frequently Asked Questions
What is the primary focus of this research?
The research focuses on the influence of 3-hydroxybutyrate and electrical microcurrents on cardiomyocytes, particularly under conditions that simulate heart failure-induced hypertrophy.
What are the central themes discussed in the work?
The work explores metabolic alterations in heart failure, the role of ketone bodies as an energy substrate, and the impact of electrical stimulation on cellular remodeling.
What is the primary research goal or hypothesis?
The goal is to determine if 3-hydroxybutyrate affects cardiomyocyte activity and if it can reduce cell hypertrophy, while assessing whether microcurrent treatment provides a restorative effect.
Which scientific methods were employed?
The study used cell culture models (H9c2 and SHR7), immunohistochemical staining, alamarBlue assays for viability, and mitochondrial tracking via microscopy.
What is covered in the main body of the work?
The main body details the experimental setup of the hypertrophic model, measurements of cell size, proliferation assays under ketone treatment, and the imaging of mitochondrial distribution.
Which keywords best characterize this work?
Key terms include Chronic Heart Failure, Cardiomyocytes, 3-Hydroxybutyrate, Microcurrent Therapy, and Hypertrophy.
How does Phenylephrine affect the cardiomyocyte models?
Phenylephrine (PE) is used to induce a hypertrophic state in the cells, which involves significant cell enlargement and the translocation of Caveolin-3 into the cytoplasm.
What effect did 3-hydroxybutyrate (OHB) have on cell size?
The study demonstrated that treatment with 6.25mM OHB could significantly reduce the cell size of hypertrophic cardiomyocytes back towards the dimensions of untreated cells.
Was the microcurrent treatment found to be effective?
Yes, the results suggested that microcurrent application could serve as a promising therapeutic method, as it demonstrated a reduction of cellular hypertrophy both in vitro and in vivo.
- Quote paper
- BSc Matthias Pilecky (Author), 2010, The Influence of 3-Hydroxybutyrate and Microcurrent Treatment on Cardiomyocytes during Simulated Hypertrophy, Munich, GRIN Verlag, https://www.hausarbeiten.de/document/168718
