Study on the efficacy of umbilical cord stem cells for diabetes mellitus

Diabetes mellitus (DM) is a terribly growing epidemic, currently affecting about 463 million people worldwide, with expected rise to 700 million by the year 2045.

It is the most prevalent metabolic disease, in which insulin secreting β cells are damaged to various extents. Different etiologies and interfering factors exist for each of type 1 and type 2 DM (T1DM and T2DM), the most famous well-known types. However, β cell dysfunction and hyperglycemia are disease hall-marks for both types, and diabetic complications, as well as decreased life quality and increased mortality are unfortunately inevitable in most cases. Accordingly, there is an urgent need to develop novel therapeutic modalities which would help not only to manage the disease, but also hopefully provide a real cure for DM. Regenerative medicine and stem cell therapy opened new avenues and ignited much hope for patients with DM over the past few years.

Various types of stem cells have been investigated regarding their therapeutic potential for DM in the preclinical as well as clinical settings. Interestingly, among the various sources of stem cells, the umbilical cord (UC) has proved to be a unique source, providing several advantages over other sources. Most importantly, UC-derived stem cells are readily available and can be obtained non-invasively during the process of delivery. Moreover, their banking potential adds a lot to their importance for regenerative medicine.

Several previous meta-analyses concluded the safety as well as therapeutic efficacy of stem cell therapy in DM. Nevertheless, published meta-analyses mostly combined studies which applied MSCs derived from various sources including the bone marrow-MSCs, placenta-MSCs, as well as WJ-MSCs together, and some also combined UCB together with peripheral blood mononuclear cells (PB-MNCs), or included studies which employed UCB transplantation, together with those employing “stem cell educator” therapy. While others pooled all different types of stem cell therapies together including UCB, WJ-MSCs, as well as HSCs and other types of MSCs. Additionally, previously, we compared the therapeutic effect of WJ-MSCs and UCB-derived MSCs in streptozotocin-induced diabetic rats. Interestingly, we found that WJ-MSCs can better control hyperglycemia in diabetic rats in vivo and also better differentiate into insulin producing cells in vitro, as compared with UCB-MSCs.

The results of the current study also shed lights on the importance to consider cryopreservation/banking of WJ-MSCs together with the well-established routine banking of UCB, especially for those with family history of DM. Additionally, the current study highlights the crucial need for additional well-designed randomized controlled trials with larger cohorts, in order to fill the obvious gap between pre-clinical and clinical studies. Undoubtedly, the future will unravel much more findings concerned with the therapeutic mechanisms of action, as well as methods to maximize the therapeutic benefits of WJ-MSCs.