What are Peripheral Vascular Diseases, including Critical Limb Ischemia?
Peripheral vascular disease is any disease that affects the arteries and veins. The most common form is peripheral artery disease, which develops when the arteries that supply blood to the internal organs, arms, and legs become blocked from atherosclerosis. Atherosclerosis is a process in which cholesterol plaque accumulates in one’s artery walls, causing a narrowing of the artery channel. Often this process begins early in one’s life but does not show symptoms. As the condition progresses, it can lead to painful exercise, strokes, heart attacks, and angina (a lack of blood flow to the heart).
Although half of affected patients live with no symptoms, the most common signs of the disease are cramping and pain during exercise or even rest. Other signs include numbness in the hands and feet, weakness in the calves, coldness in the legs and feet, hair loss on the feet, thickening of toenails, and painful ulcers.
Those with high cholesterol levels, high blood pressure, or a history of smoking, diabetes, or obesity are at a higher risk of contracting the condition. Because of its lifestyle-based origins, treatment can be as simple as a following a healthy diet, exercising, and quitting smoking.
Critical Limb Ischemia (CLI) is the most advanced state of peripheral artery disease. The condition occurs when the arteries have been obstructed and therefore blood flow to the body’s extremities has been blocked. This lack of blood flow can cause extreme pain during rest, skin ulcers, and even gangrene. Patients with CLI have elevated risk of heart attack, stroke, and blood vessel death, and a large percentage of patients are at risk of limb amputation.
Some causes of the disease include smoking, diabetes, obesity, high cholesterol, and high blood pressure. Men and women over the age of 60 who do not exercise are the most commonly affected. Symptoms resemble those of peripheral artery disease and include pain, sores, and hair loss in the extremities. However, these symptoms will be more frequent and severe because the condition occurs in several areas of the arteries. Those affected should seek immediate treatment from a specialist or surgeon.
How can Celltex stem cell therapy help?
Stem cell therapies are actively being explored pre-clinically and clinically. Based on these studies, there is strong evidence that MSCs under certain conditions may help promote new blood vessel formation and enhanced blood perfusion in ischemic tissues via secretion of multiple factors including VEGF, FGF, HGF, SDF-1 and Ang-1. In addition, several small clinical studies have been conducted that demonstrate promise. Specifically, a recent small prospective double blind randomized placebo controlled multi-center study (with 20 patients) demonstrated safety and positive trends in ankle brachial pressure index and ankle pressure in the cell arm compared to controls, warranting larger studies to assess therapeutic efficacy. In another small clinical study with 41 CLI patients with diabetes mellitus, MSCs performed better than bone marrow mononuclear cells – while both groups experienced improved pain-free walking time, MSCs exhibited better collateral blood vessel scores and faster wound healing effects. Interestingly, a recent CLI study in mice has shown the injection of MSCs into the boarder zone can improve new blood vessel formation and enhanced blood perfusion in the ischemic region. Results to date have been promising, and the next step will be to demonstrate therapeutic effects as primary endpoints in large randomized placebo controlled studies. Transplantation of Mesenchymal Stem Cells in humans for a variety of conditions has been generally well tolerated.
Research articles on use of stem cells in Critical Limb Ischemia can be found here:
Examples of current and completed clinical trials registered at FDA.gov can be found here: