The Efficacy of Umbilical Cord (UC) Serum, Human Platelet Lysate, and the Synergistic Effect of Nano-curcumin and Crocin as Supplements in the Proliferation and Survival of Human UC-derived Mesenchymal Stromal Cells (MSCs).

Introduction: Fetal Bovine Serum (FBS), the conventional supplement for Mesenchymal Stromal Cell (MSC) culture, presents ethical issues, batch variability, and risks of pathogen transmission. This study aimed to evaluate human-derived Umbilical Cord Serum (UCS) and Human Platelet Lysate (HPL) as xeno-free alternatives to FBS and to assess the synergistic effects of nano-curcumin and crocin as supplements to enhance the proliferation and survival of human umbilical cord-derived MSCs.

Methods: Human umbilical cord-derived MSCs were cultured in media supplemented with 10% FBS (control), UCS, or HPL. These groups were further treated with nano-curcumin (0.3 μM) or crocin (2.5 μM), either individually or in combination. Cell proliferation was measured using the MTT assay, apoptosis was assessed by Annexin V/PI flow cytometry, and pluripotency gene expression (Sox2, Nanog, Oct4) was analyzed by RT-qPCR.

Results: UCS and HPL supplements significantly increased MSC proliferation compared to the FBS control (p < 0.001). Specifically, UCS reduced the population doubling time by approximately 50%. Supplementation with crocin reduced apoptosis by up to 30% (p = 0.04) and significantly enhanced the expression of the pluripotency genes Sox2 and Nanog, particularly in cultures supplemented with HPL. In contrast, nano-curcumin inhibited MSC proliferation and increased apoptosis across all tested conditions.

Discussions: The results demonstrate that UCS and HPL are effective, viable alternatives to FBS, promoting superior MSC expansion. The anti-apoptotic and stemness-enhancing properties of crocin highlight its potential as a valuable additive for improving culture quality and cell survival. The cytotoxic effects observed with nano-curcumin underscore a critical need for dose-optimization studies. The primary limitation of this study is the use of fixed concentrations for the supplements, which warrants further investigation across a range of doses.

Conclusion: UCS and HPL are robust, ethically sound replacements for FBS in MSC biomanufacturing. Crocin can further enhance culture outcomes by improving cell survival and maintaining stem cell properties. These findings support the development of optimized, xeno-free culture systems for scalable MSC production, which is crucial for advancing regenerative medicine therapies.