The idea that adipose tissue is a reservoir of heat and an energy source has been changed with research highlighting the tissue involved in intricate interactions with other systems of our body: cardiovascular, nervous and endocrine systems. A secretome attributed to the adipose tissue that includes growth factors and adipocytokines making this endocrine activity extremely attractive for valuable healing.
Adipose tissue-derived stem cells (ADSCs) are mesenchymal cells that can undergo self-renewal and have been differentiated into many cells like osteoblasts, adipocytes, chondrocytes, nerve cells and muscle cells. The biggest advantage of these cells is their lack of ethical issues when compared with embryonic stem cells. Another advantage is the accessibility of ADSCs that can be isolated by subcutaneous lipoaspiration.
According to scientists, Miana and González (2018), MSCs from adipose tissue can be isolated using direct excision following surgery, liposuction (removing unwanted fat from one part of the body and injection into another part) and the Coleman technique (this approach is followed for the transplantation of fat and its remodeling-the yield of viable adipocytes has been higher using this approach). The material so isolated is subjected to washing, enzymatic digestion and centrifugation to obtain the stromal vascular fraction (SVF) that is the source of cells such as monocytes, fibroblasts and mesenchymal stem cells.
In animal models, early work has shown much promise: for example, the injection of adipose tissue stem cells in damaged tibialis anterior muscles of rats resulted in an increased mass of the muscle along with contractive forces showing healing and functions due to stem cell administration (Bacou and team, 2004). In another study from Chandra and team (2009), human adipose tissue-derived adult stem cells were reported to be “an ideal population of personal stem cells for cell replacement therapy”. This arises from the formation of islet-like cell aggregates from the human adipose cells that secreted insulin and human-C-peptide. When these cells were transplanted into diabetic mice, normal levels of glucose were achieved in the mice showing the promise of deriving functional islets from adipose-derived stem cells.
According to the World Health Organization, 1.9 billion adults were overweight in 2016; with overall numbers of obese people three times of what was observed in 1975.Apart from “image” issues, obesity is a major risk factor associated with heart disease, stroke, musculoskeletal disorders like osteoarthritis, diabetes and some cancers. A 2019-published article by Shree and team reported the promise of using MSCs derived from adipose tissue to manage the affected metabolism in high-fat diet (HFD)-induced C57BL/6 mice. The animals that received stem cells showed lowered oxidized LDL, IL6 and insulin resistance. The metabolism that went for a toss in obesity was corrected by the stem cells that migrated to different organs. The cell suspension was found to lower the hypertrophy of the islets and entry of fats inside the liver as well as reduced infiltration of macrophages in adipose tissues-all manifestations of aberrant metabolism due to obesity. This opens up a new therapeutic approach to manage obesity using stem cells derived from the adipose tissues and correct the dysregulated metabolism induced by obesity.
The word “adipose tissue” often instils fear in many given its association with “fat”-however, the promise of adipose tissue-derived stem cells in studies and their ease of isolation makes “fat” promising to be used to treat chronic diseases that are yet to see effective treatments.
Miana, V. V., & González, E. (2018).Adipose tissue stem cells in regenerative medicine. Ecancermedicalscience, 12, 822.https://doi.org/10.3332/ecancer.2018.822
Bacou F, AndalousiRBE, Daussin PA, et al. Transplantation of Adipose Tissue-Derived Stromal Cells Increases Mass and Functional Capacity of Damaged Skeletal Muscle. Cell Transplant. 2004 Mar; 13(2):103-111.
Chandra V, G S, Phadnis S, et al. Generation of pancreatic hormone-expressing islet-like cell aggregates from murine adipose tissue-derived stem cells. Stem Cells. 2009;27(8):1941–1953. doi: 10.1002/stem.117.
Shree, N., Venkategowda, S., Venkatranganna, M.V. et al. Human adipose tissue mesenchymal stem cells as a novel treatment modality for correcting obesity-induced metabolic dysregulation. Int J Obes 43, 2107–2118 (2019). https://doi.org/10.1038/s41366-019-0438-5