In a attempt to ascertain if stem cell therapy can prevent or improve a condition called "diabetic foot" caused by poor blood flow in patients with diabetes, a team of research workers in China has found that transplanting human placenta-derived mesenchymal stem cells (MSCs) into rats modeled with diabetes can affect blood vessel development, possibly improving blood circulation and preventing critical limb ischemia (CLI), a condition that results in diabetic foot and often leads to amputation as described at diabetes forum.
The study will be published in a future issue of Cell Transplantation and is now freely accessible on-line as an unedited, early epub at: http://www.ingentaconnect.com/content/cog/ct/pre-prints/content-ct-1594_liang_et_al
"CLI describes an advanced stage of peripheral artery disorder characterized by obstruction of the arteries and a noticeably reduced blood flow to the extremities. CLI is associated with high rates of mortality and morbidity, putting the patients at high-risk for major amputation," said study co-author Dr. Zhong Chao Han of the Beijing Institute of Stem Cells, Health and Biotech. The utility of placenta-derived MSCs is ill understood, so we sought to investigate the effectiveness of combined regular therapy and cell therapy in treating diabetes-related CLI."
Based on the researchers, human placenta was got from full term cesarean section deliveries with written informed consent of the mother.
After injection into rats surgically modeled with CLI, the stem cells counted and were tracked at various points in time. A few cells differentiated into vascular cells, although the researchers found the stem cell counts fell dramatically over time. The infused cells also secreted cytokines, which are small proteins secreted by cells that have a certain effect on communications and the interactions between cells.
"We believe that cytokines secreted by MSCs bring endothelial cells, a kind of cells which make up the tissues lining the interior surface of arteries," said the researchers. "These cells participate in building new vascular tissues and also inhibit inflammation."
The researchers concluded that their experimental data implied that MSCs enhanced ischemia recovery in diabetic rats via direct cell differentiation and paracrine (protein-mediated) mechanisms, although both mechanisms exist simultaneously. The paracrine mechanisms, said the researchers, were likely more significant than direct cell differentiation.
"So far, MSC therapy represents an easy, safe and effective therapeutic approach for diabetes and its complications," the researchers concluded. "Our studies place the basis for the transition in the experimental seat to the clinical bedside."
"Future studies should aim to expound upon previous findings in MSC transplantation studies and affirm the effectiveness of placenta-derived MSCs for CLI." Get the complete draft at diabetes forums.