Small molecules and extrinsic factors promoting differentiation of stem cells into insulin-producing cells

In silico discovery of small molecules for efficient stem cell differentiation into definitive endoderm

Improving methods for human embryonic stem cell differentiation represents a challenge in modern regenerative medicine research. Using drug repurposing approaches, we discover small molecules that regulate the formation of definitive endoderm. Among them are inhibitors of known processes involved in endoderm differentiation (mTOR, PI3K, and JNK pathways) and a new compound, with an unknown mechanism of action, capable of inducing endoderm formation in the absence of growth factors in the media. Optimization of the classical protocol by inclusion of this compound achieves the same differentiation efficiency with a 90% cost reduction. The presented in silico procedure for candidate molecule selection has broad potential for improving stem cell differentiation protocols.

Molecular study of the proliferation process of beta cells derived from pluripotent stem cells

BACKGROUND

Diabetes mellitus (DM) is a chronic metabolic disorder, increasing in the number of patients and poses a severe threat to human health. Significant advances have been made in DM treatment; the most important of which is differentiation and proliferation of beta cells from IPSCs.

METHODS

Data were collected from PUBMED at various time points up to the academic year of 2020. The related keywords are listed as follows: "Induced pluripotent stem cell", "Proliferation", "Growth factor", "Small molecule", "cardiotoxicity" and "Scaffold."

RESULT

The use of growth factors along with small molecules can be a good strategy for beta-cell proliferation. Also, proliferation of beta cells on nanofibers scaffolds can create a similar in vivo environment, that leads to increased function of beta-cell. Some transcription factors that cause beta cells proliferation play an important role in inflammation; so, it is essential to monitor them to prevent inflammation.

CONCLUSION

Finally, the simultaneous use of growth factors, micronutrients and scaffolds can be an excellent strategy to increase the proliferation and function of beta cells derived from IPSCs.

Therapeutic Potentials of MicroRNAs for Curing Diabetes Through Pancreatic β-Cell Regeneration or Replacement

MicroRNAs are a type of noncoding RNAs that regulates the expression of target genes at posttranscriptional level. MicroRNAs play essential roles in regulating the expression of different genes involved in pancreatic development, β-cell mass maintenance, and β-cell function. Alteration in the level of miRNAs involved in β-cell function leads to the diabetes. Being an epidemic, diabetes threatens the life of millions of patients posing a pressing demand for its urgent resolve. However, the currently available therapies are not substantial to cure the diabetic epidemic. Thus, researchers are trying to find new ways to replenish the β-cell mass in patients with diabetes. One promising approach is the in vivo regeneration of β-cell mass or increasing the efficiency of β-cell function. Another clinical strategy is the transplantation of in vitro developed β-like cells. Owing to their role in pancreatic β-cell development, maintenance, functioning and their involvement in diabetes, overexpression or attenuation of different miRNAs can cause β-cell regeneration in vivo or can direct the differentiation of various kinds of stem/progenitor cells to β-like cells in vitro. Here, we will summarize different strategies used by researchers to investigate the therapeutic potentials of miRNAs, with focus on miR-375, for curing diabetes through β-cell regeneration or replacement.

Different combinations of GABA, BMP7, and Activin A induced the in vitro differentiation of rat pancreatic ductal stem cells into insulin-secreting islet-like cell clusters

AIMS

We investigated the in vitro differentiation of adult rat PDESCs into β-like cells through supplementation of different combinations of GABA, BMP7, and Activin A in basic culture media.

MATERIALS AND METHODS

The PDESCs were cultured using different inducement combinations for 28 days and microscopy, dithizone (DTZ) staining, immunohistochemical staining, real-time PCR, and glucose-stimulated insulin secretion (GSIS) assay were used to delineate the differentiation inducement potential of these combinations.

KEY FINDINGS

The results show that after 28 days, the PDESCs were differentiated into ICCs containing insulin-secreting β-like cells in different groups treated with A + B, A + G, B + G, and A + B + G but not in the control group. Upon DTZ staining the cells in ICCs were stained crimson red, demonstrating the presence of β-like cells in ICCs and the immunohistochemistry showed the expression of Pdx1 and insulin in ICCs. Further, on 28 d the expression of Pdx1 and insulin mRNA was high in inducement groups as compared to the control group and β-like cells in ICCs also secreted insulin and C-peptide upon glucose stimulation. Thus, the supplementation of GABA, BMP7, and Activin A in different combinations in basic culture media can induce the in vitro differentiation of PDESCs into ICCs containing β-like cells.

SIGNIFICANCE

The in vitro development of β-like cells is a herald for cell therapy of diabetic patients and our results are a step closer towards finding the cure for diabetes.

Small Molecule-Induced Pancreatic β-Like Cell Development: Mechanistic Approaches and Available Strategies

Diabetes is a metabolic disease which affects not only glucose metabolism but also lipid and protein metabolism. It encompasses two major types: type 1 and 2 diabetes. Despite the different etiologies of type 1 and 2 diabetes mellitus (T1DM and T2DM, respectively), the defining features of the two forms are insulin deficiency and resistance, respectively. Stem cell therapy is an efficient method for the treatment of diabetes, which can be achieved by differentiating pancreatic β-like cells. The consistent generation of glucose-responsive insulin releasing cells remains challenging. In this review article, we present basic concepts of pancreatic organogenesis, which intermittently provides a basis for engineering differentiation procedures, mainly based on the use of small molecules. Small molecules are more auspicious than any other growth factors, as they have unique, valuable properties like cell-permeability, as well as a nonimmunogenic nature; furthermore, they offer immense benefits in terms of generating efficient functional beta-like cells. We also summarize advances in the generation of stem cell-derived pancreatic cell lineages, especially endocrine β-like cells or islet organoids. The successful induction of stem cells depends on the quantity and quality of available stem cells and the efficient use of small molecules.