Herbal pre-conditioning induces proliferation and delays senescence in Wharton's Jelly Mesenchymal Stem Cells

Background Mesenchymal Stem Cells (MSCs) are multipotent stem cells which are being explored for various clinical applications. Isolation and in-vitro expansion of MSCs remain important in achieving desired cell number for the therapy. However, in-vitro proliferation of MSCs is often associated with senescence and early onset of apoptosis which limits its therapeutic ability and long term clinical use. Tinospora cordifolia and Withania somnifera are used widely in Ayurveda: the traditional Indian system of medicine and are reported to have rejuvenating and anti-aging potential. In the present study, we investigated the effect of Tinospora cordifolia and Withania somnifera on proliferation and senescence of wharton's jelly MSCs (WJMSCs) in-vitro. Methods WJMSCs were treated in culture medium with Tinospora cordifolia leaf and Withania somnifera root extracts to examine their effect on proliferation and senescence properties of WJMSCs. Proliferation of WJMSCs was assayed by cell count, MTT, BrdU incorporation assay, cell cycle analysis and Ki67 mRNA expression. Senescence was demonstrated using β-galactosidase senescence assay and associated mRNA markers. Results Culture medium supplemented with Tinospora cordifolia leaf and Withania somnifera root extracts exhibited significant increase in proliferation of WJMSCs as evidenced by cell count and MTT assay. Cell cycle analysis using propidium iodide showed increase in G2/M phase and decrease in apoptotic cells. BrdU incorporation and upregulation of proliferation marker ki67 by RT PCR showed increased DNA synthesis/proliferation in Tinospora cordifolia and Withania somnifera extract treated MSCs. Delayed senescence was confirmed by β-galactosidase senescence assay and down regulation of senescence marker p21. Conclusion Our results demonstrate for the first time that Tinospora cordifolia and Withania somnifera extracts support proliferation and inhibit senescence in WJMSCs making them suitable candidates as supplements for in-vitro expansion without affecting the cell viability indicating its non-toxic nature.