Role of Insulin-like Growth Factor 1 Receptor Signaling in Stem Cell Stemness and Therapeutic Efficacy

# Role of Insulin-like Growth Factor 1 Receptor Signaling in Stem Cell Stemness and Therapeutic Efficacy

## Abstract

Recent studies show that stem cells are a promising tool for repairing damaged tissues and developing regenerative medical therapies. To harness their potential, it's important to identify stem cells with strong self-renewal abilities and the capacity to develop into various cell types. The insulin-like growth factor 1 receptor (IGF1R) plays a crucial role in maintaining these vital properties of stem cells, allowing them to thrive and be used effectively in treatments. We will explore how IGF1R signaling affects different types of stem cells—such as human embryonic stem cells, neural stem cells, and bone marrow-derived stem cells—and how boosting this signaling may enhance the efficacy of stem cell therapies.

## Introduction

Stem cells are unique cells with the ability to divide repeatedly (self-renewal) and generate specialized cells that make up various tissues in the body. There are two main types of stem cells: pluripotent embryonic stem cells (ESCs) from early-stage embryos, which can turn into any cell type, and multipotent adult stem cells, which originate from different tissues and can only develop into specific cell types, like mesenchymal stem cells (MSCs) found in bone marrow and connective tissues.

Given their versatile nature, stem cells hold significant promise for addressing various medical conditions through regenerative therapies, including bone marrow transplants and healing heart tissues after a heart attack. A key consideration in effectively using stem cells for therapies is identifying and sustaining those with the greatest ability to self-renew and differentiate into desired cell types.

## IGF1R Signaling and Stem Cell Function

The insulin-like growth factor 1 receptor (IGF1R) is a protein on cell surfaces that binds to growth factors IGF1 and IGF2. When activated, IGF1R triggers pathways inside the cell that promote growth, division, and survival, while also preventing cell death.

Research indicates that stem cells expressing IGF1R show better self-renewal and differentiation potential, making them ideal candidates for therapy. Enhancing IGF1R signaling in these cells might help maintain their properties and improve the outcomes of stem cell treatments for various diseases, such as heart failure, neurodegeneration, and bone disorders.

Continued investigations into how to effectively modify IGF1R signaling may lead to better strategies for stem cell applications in regenerative medicine.

## Clinical Implications

1. **Human Embryonic Stem Cells (hESCs)**: Maintaining hESCs in optimal cultures can significantly benefit from IGF1R signaling, enhancing both their growth and differentiation capabilities.

2. **Neural Stem Cells (hNSCs)**: These cells are being studied for their potential in treating ALS, a serious neurodegenerative condition. By stimulating IGF1R signaling, it may be possible to bolster their ability to protect and regenerate nerve cells.

3. **Cardiac Stem Cells (hCSCs)**: Identifying hCSCs with high IGF1R expression can improve cardiac repair following injury due to heart attacks, highlighting the importance of signaling in cardiac regeneration.

4. **Bone Marrow Derived Stem Cells (hBMMSCs)**: The effectiveness of hBMMSCs in enhancing heart repair processes hinges on successful IGF1R modulation, which can enhance their survival and ability to generate new cardiovascular tissue.

5. **Placental Mesenchymal Stem Cells (hPMSCs)**: These cells found in the placenta exhibit multipotency, and their therapeutic potential can be maximized through IGF1R signaling influences in controlled environments.

6. **Dental Pulp Stem Cells (hDPSCs)**: hDPSCs represent an accessible source of stem cells. Improvements in culture conditions that promote IGF1R activation can enhance their regenerative potential in treating neurodegenerative diseases.

## Conclusion

Despite some ethical debates surrounding stem cell use, their application in treating diseases continues to advance through ongoing clinical trials. Identifying stem cells that retain strong self-renewal and differentiation traits is crucial for effective treatments. This literature review emphasizes IGF1R signaling as a significant marker for selecting viable stem cells, and enhancing its activity could improve therapeutic applications of stem cells in regenerative medicine.