The function of stem cells and their future roles in healthcare

Study of Stem Cells in Human Milk

Stem cells are cells that have the ability to self-renew into an undifferentiated cell state, which can further delineate into distinct cell types. There are various sources of stem cells in the human body; some of them include cord blood, placental tissue, bone marrow, adipose tissue, dental pulp, etc. 

Breast milk could become an important source of stem cells in the near future because of its non-invasive isolation technique. Based on this nature, this study was conducted to isolate stem cells from breast milk and to show further potential implications of these cells. The total number of cells isolated from the milk ranged from 1.5 × 10⁵ cells to 3 × 10⁵ cells. As there was prolongation in the lactation period, the number of cells in the milk lowered significantly. There was no significant difference in the cell count in various gestational age groups. The cytochemistry analysis of these cells with their specific cell markers confirmed the presence of a homogenous population of mesenchymal stem cells. Further differentiation of these breast milk stem cell analyses showed transformation into adipocytes, chondrocytes, and osteoblasts in different culture mediums. So the presence of mesenchymal stem cells in human milk, which are multipotent in nature, makes it an important source of stem cells for further regenerative therapies, tissue culture techniques, and gene therapies. Due to this nature, these cells can be redirected to produce various tissues in the human body.

Exercise, Diet and Sleeping as Regenerative Medicine Adjuvants: Obesity and Ageing as Illustrations

Regenerative medicine uses the biological and medical knowledge on how the cells and tissue regenerate and evolve in order to develop novel therapies. Health conditions such as ageing, obesity and cancer lead to an impaired regeneration ability. Exercise, diet choices and sleeping pattern have significant impacts on regeneration biology via diverse pathways including reducing the inflammatory and oxidative components. Thus, exercise, diet and sleeping management can be optimized towards therapeutic applications in regenerative medicine. It could allow to prevent degeneration, optimize the biological regeneration and also provide adjuvants for regenerative medicine.

Regulation of Stem Cell-Based Research in India in Comparison with the US, EU and other Asian Countries: Current Issues and Future Perspectives

Stem cell therapy is applicable for repair and replacement of damaged cells and tissues. Apart from transplanting cells to the body, the stem cell therapy directs them to grow new and healthy tissues. Stem cells in the area of regenerative medicines hold tremendous promise that may help to regenerate the damaged tissues and heal various diseases like multiple sclerosis, heart diseases, Parkinson's disease, and so on. To prove the safety, efficacy, and for the requirement of a licence for manufacturing and sale, all the stem cell therapies should pass the required criteria and undergo certain examinations of the regulatory agencies. The regulatory authorities review the manufacturing procedures of products to assure its purity and potency. This review summarizes the comparative critical evaluations of existing regulations and developments on the stem cells research in India, USA, EU and Asian regions and also discusses the challenges that have to be overcome and the important points that should be understood to position India as a source of the perspective nation in stem cells around the world.

Cardiac Progenitor Cells from Stem Cells: Learning from Genetics and Biomaterials

Cardiac Progenitor Cells (CPCs) show great potential as a cell resource for restoring cardiac function in patients affected by heart disease or heart failure. CPCs are proliferative and committed to cardiac fate, capable of generating cells of all the cardiac lineages. These cells offer a significant shift in paradigm over the use of human induced pluripotent stem cell (iPSC)-derived cardiomyocytes owing to the latter's inability to recapitulate mature features of a native myocardium, limiting their translational applications. The iPSCs and direct reprogramming of somatic cells have been attempted to produce CPCs and, in this process, a variety of chemical and/or genetic factors have been evaluated for their ability to generate, expand, and maintain CPCs in vitro. However, the precise stoichiometry and spatiotemporal activity of these factors and the genetic interplay during embryonic CPC development remain challenging to reproduce in culture, in terms of efficiency, numbers, and translational potential. Recent advances in biomaterials to mimic the native cardiac microenvironment have shown promise to influence CPC regenerative functions, while being capable of integrating with host tissue. This review highlights recent developments and limitations in the generation and use of CPCs from stem cells, and the trends that influence the direction of research to promote better application of CPCs.

Stem cell therapy for the treatment of parasitic infections: is it far away?

Stem cell therapy is an interventional treatment that introduces new cells into damaged tissues, which help in treating many diseases and injuries. It has been proved that stem cell therapy is effective for the treatment of cancers, diabetes mellitus, Parkinson's disease, Huntington's disease, cardiovascular diseases, neurological disorders, and many other diseases. Recently, stem cell therapy has been introduced to treat parasitic infections. The culture supernatant of mesenchymal stem cells (MSCs) is found to inhibit activation and proliferation of macrophages induced by the soluble egg antigen of Schistosoma japonicum, and MSC treatment relieves S. japonicum-induced liver injury and fibrosis in mouse models. In addition, transplantation of MSCs into naïve mice is able to confer host resistance against malaria, and MSCs are reported to play an important role in host protective immune responses against malaria by modulating regulatory T cells. In mouse models of Chagas disease, bone marrow mononuclear cell has been shown effective in reducing inflammation and fibrosis in mice infected with Trypanosoma cruzi, and transplantation of the bone marrow mononuclear cells prevents and reverses the right ventricular dilatation induced by T. cruzi infection in mice. Preliminary clinical trials demonstrate that transplantation of bone marrow derived-cells may become an important therapeutic modality in the management of end-stage heart diseases associated with Chagas disease. Based on these exciting results, it is considered by stating that it is firmly believed that, within the next few years, we will be able to find the best animal models and the appropriate stem cell type, stem cell number, injection route, and disease state that will result in possible benefits for the patients with parasitic infections, and stem cell therapy, although at an initial stage currently, will become a real therapeutic option for parasitic diseases.

[Experimental models in oncology: contribution of cell culture on understanding the biology of cancer]

In the beginning of the 20th century, tissue culture was started with the aim of studying the behaviour of animal cells in normal and stress conditions. The cell study at molecular level depends on their capacity of growing and how they can be manipulated in laboratory. In vitro cell culture allows us the possibility of studying biological key processes, such as growth, differentiation and cell death, and also to do genetic manipulations essential to the knowledge of structure and genes function. Human stem cells culture provides strategies to circumvent other models' deficiencies. It seems that cancer stem cells remain quiescent until activation by appropriated micro-environmental stimulation. Several studies reveal that different cancer types could be due to stem cell malignant transformations. Removal of these cells is essential to the development of more effective cancer therapies for advanced disease. On the other hand, dendritic cells modified in culture may be used as a therapeutic vaccine in order to induce tumour withdraw.

Autologous bone marrow transplantation/mobilization: A potential regenerative medicine for systemic degenerative disorders and healthy living

Increased longevity is compromised for the quality of life due to prevalence of metabolic derangements and systemic degenerative disorders, as a result of lifestyle changes in modern days. In a craze to improve upon quality of life, use of pharmacological formulations aimed towards symptomatic treatment regimen is mandatory to manage variety of prevailing human ailments. However; these medicines have their own limitations and side effects, soliciting alternative therapy for better living. In light of preclinical and clinical studies on adult stem cells, bone marrow transplantation in healthy elderly individuals is likely to promote rejuvenation and prevent onset of degenerative disorders as well as cure prevailing disorders if any. Progress in unraveling pleuripotency of adult bone marrow stem cells compelled us to hypothesize that the only way to regain lost cells is to replace them with cells following the principle of 'Like begets Like' which may be achieved by autologous bone marrow transplantation/mobilization.

MicroRNA: a new player in stem cells

microRNAs (miRNAs) are an abundant class of endogenous non-protein-coding small RNAs, which negatively regulate gene expression at the posttranscriptional level in many developmental and metabolic processes. miRNAs regulate a variety of biological processes, including developmental timing, signal transduction, tissue differentiation and maintenance, disease, and carcinogenesis. Emerging evidence demonstrates that miRNAs also play an essential role in stem cell self-renewal and differentiation. Some miRNAs are specifically expressed in stem cells, control stem cell self-renewal, and differentiation through negatively regulating the expression of certain key genes in stem cells.