New research shows that the use of human dental pulp stem cells (DPSC) may alleviate the most severe symptoms of induced diabetic neuropathy in rats. Diabetic neuropathies (DN) are a well-known complication of diabetes, and can produce permanent nerve damage in affected individuals. The exact causes of DN are unconfirmed, but chronically elevated glucose levels may damage the small blood vessels that serve the affected peripheral and motor nerves. In rare cases, DN can also affect the autonomic nerve system.
Common neuropathies include autonomic neuropathy; diabetic amyotrophy; mononeuropathy; mononeuropathy multiplex; third nerve palsy; and thoracoabdominal neuropathy. Symptoms often include numbness, tingling, burning and pain in the extremities; localized phantom pains or sensations; loss of muscle control in the face, lips and eyelids; changes in vision or speech; balance and swallowing problems; sexual dysfunction; diminished bladder and bowel control; and muscle spasms.
Half of all diabetic patients (Type 1 and Type 2) eventually develop one or more DN conditions. Diabetic neuropathy can lead to chronic ulcerations in the lower extremities, which increase the likelihood of amputation and other complications. Currently, DN treatments focus on glucose management to avoid the onset of the condition, and treatment of pain and other symptoms following DN onset. While these treatments may address some facets of DN, most do not reduce inflammation, thought to be a significant source of nerve damage in affected patients.
Dental pulp stem cells trigger functional recovery from DN
In a study recently published in Cytotherapy, researchers in Bengaluru, India induced DN in rats. Six weeks after induction of the condition, the researchers introduced DPSC into two study groups. One group of rats received intramuscular injections of dental pulp stem cells. The other group received IV DPSC transplantation. The subjects received either a single dose or two repeat doses of DPSC. A control group received no treatment.
Two weeks after stem cell treatment, researchers observed rapid improvements in typical DN symptoms among rats receiving a single IV-transplanted stem cell dose. In subjects that received a repeat dose, researchers did not note additional symptom relief. Subjects that received an intramuscular injection did not show as much symptomatic relief as the IV group, however, the IM group saw a significant improvement in body weight. Both treatments provided reduction in tumor necrosis factor (TNF) and C-reactive protein in blood levels. Subjects that received repeat IM doses also showed better reduction of DN-related inflammation in affected tissues in the body. In rats that received a repeat IM dose of DPSC, researchers noted additional reductions in DN-related inflammation.
The researchers chose DPSC because it is a promising source of mesenchymal stem cells. DPSC also avoids potential complications that can result from the use of MSC sourced from bone marrow. Mesenchymal stem cells can target areas of disease in the body and differentiate accordingly. The researchers noted that while IV transplantation of a single dose produced significant improvement of some symptoms, repeat IM doses of DPSC produced more effective control of the most damaging elements of DN conditions in the test subjects.
Stem cell research may direct new DN treatments
The research offers promising clues into a potential, highly effective treatment for DN conditions that not only relieve pain-related symptoms in the peripheral and motor nervous systems, but also address the less understood but potentially more damaging inflammation that characterizes the conditions.
If you would like more information about dental pulp stem cells and its role in medical research, or you are interested in preserving dental pulp stem cells for potential use in promising stem cell treatments, please contact us as the National Dental Pulp laboratory.
Photo Credit: Aleksey Krasavin, via Flickr