Type 2 diabetes (T2DM) is one of the most serious chronic diseases that threaten human life and health. The main clinical manifestations are insulin resistance and depletion of pancreatic islet functions. Traditional T2DM drugs are difficult to restore blood glucose back partially among patients, and may cause various adverse reactions such as hypoglycemia, diarrhea, nausea, and vomiting.

In recent years, stem cell therapies represented by mesenchymal stem cells (MSCs) have provided new strategies and prospects for the treatment of diabetes. However, the microenvironmental stress generated by high glucose in diabetic patients significantly inhibits the survival time of MSCs in vivo and ultimately impairs the therapeutic effects.

Recently, Du Yanan's research team at the Tsinghua University School of Medicine has published the latest research results on Science Advances that can address the above problems . The research team genetically engineered MSCs with Exendin-4 (MSC-Ex-4). The modified MSCs improved their survival in the high-glucose environment of diabetes and significantly enhanced the therapeutic effects on T2DM.

In order to further enhance the therapeutic effects, the researchers used CytoNiche's 3D microcarriers to encapsulate MSC-Ex-4 for in vivo delivery, thus successfully extending the survival time of MSC-Ex-4 in vivo to one month after the single-dose subcutaneous injection. At the same time, the therapeutic effects on diabetes were enhanced and last for more than two months.

Highlights

The 3D microcarrier used in the research is 3D TableTrix^® Microcarrier, which is the core product from CytoNiche. The relevant technologies were derived from the transformation of scientific and technological achievements of Tsinghua University. It can be used as the microenvironment for stem cell growth that assists efficient stem cells in the treatment.

Gelatin Microcarrier and Gelatin Cellular Microcarrier Tablet for Cells have obtained 2 qualifications for pharmaceutical excipients from the National Medical Products Administration (CDE approval registration number: F20210000003, F20210000496). The later has also completed the filing of DMF qualification for pharmaceutical excipients from US FDA (DMF: 35481)

Abstract

1. The paper includes the construction of MSC-Ex-4, its potential effect mechanism of action on pancreatic cells and hepatocytes, and the therapeutic strategy for T2DM.

Fig. 1 Schematic diagram of the construction of MSC-Ex-4, its potential effect mechanism of action on pancreatic cells and hepatocytes, and the therapeutic strategies for T2DM.

(A) Exendin-4 genetically engineered MSCs (MSC-Ex-4), constructed through the LVVs, enabled continuous release of Exendin-4 and simultaneously regulated the secretion of protein factors such as APOM and IGFBP2.

Specifically, the Exendin-4 secreted by MSC-Ex-4 could interact with their own GLP-1R, which could potentially prolong their self-persistence under high-glucose stress.

Besides, other active factors secreted form MSC-Ex-4 could protect the pancreatic β cells through endocrine effects while improving insulin sensitivity and reducing lipid accumulation in hepatocytes through paracrine effects.

(B) Multiple systemic injections could significantly alleviate the symptoms of T ype 2 diabetes. Injectable 3D gelatin microscaffolds facilitated the role of MSC-Ex-4 as cell encapsulation and delivery vehicles, and thus single-dose local administration could achieve lasting therapeutic benefits.

2. MSC-Ex-4 demonstrated good anti-resistance performance in a simulated T2DN in vitro model of high-glucose.

Figure 2. MSC-Ex-4 had enhanced antiapoptotic and antisenescence functions under high-glucose environment, and the AMPK signaling pathway in the cells was activated (A-C). Meanwhile, MSC-Ex-4 could promote the proliferation and inhibit the apoptosis of islet cells (D-F), and activating the PI3K-AKT signaling pathway (G-I) of hepatocytes through secreted factors.

3. MSC-Ex-4 significantly alleviated the symptoms of T2DM diabetes in mice

Figure 3. Schematic diagram for systemic injection treatment of MSC-Ex-4 for (A). One week after the injection of MSC-Ex-4, the number of in vivo survival number increased (B), and the time to peak of Exendin-4 was significantly prolonged (C). The metabolic phenotypes of mice were significantly improved (D-G).

4. MSC-Ex-4 cells enabled by 3D TableTrix® microcarriers for encapsulation and delivery in vivo significantly prolonged the survival time of MSC-Ex-4 in vivo and enhanced the therapeutic effects on diabetes.

Figure 4. Schematic diagram of local injection of MSC-Ex-4 combined with 3D gelatin microscaffolds (A). The delivery assisted by 3D gelatin microscaffolds could prolong the survival time of MSC-Ex-4 to one month (B). The electron microscope image of 3D gelatin microscaffolds (C). The therapeutic effects could last for more than two months (D-E).

Summary

The above research results provide new strategies and methods for the combined use of MSC-Ex-4 and gelatin microcarriers to improve metabolic dysfunction diseases including diabetes and metabolic associated fatty liver disease (MAFLD) as well as other relevant complications (such as diabetic foot and severe diabetic lower limb ischemia).

We especially appreciate the support and efforts of Professor Du Yanan’s research team at Tsinghua University. At the same time, we are especially grateful for the hard work and advances of the R &D team at CytoNiche.

https://advances.sciencemag.org/content/7/27/eabi4379 (Original link)