by admin | Oct 11, 2018 | Stem Cell Research
Myocardial infarction, also known as heart attack, can be a devastating or even deadly event. It occurs when blood flow in one or more coronary arteries is blocked. Since coronary arteries supply blood to the heart muscle, a blockage in a coronary artery prevents oxygen and nutrients from reaching heart tissue.
While the heart can sustain short periods of time without oxygen or nutrients, heart cells become dysfunctional and die if blood flow is not restored within several hours. While clot-busting drugs, percutaneous intervention (PCI), and balloon angioplasty have provided a way to restore blood flow to the heart during a heart attack, once heart cells die there is no way to bring them back. Since most heart tissue is cardiac muscle, dead heart tissue cannot participate in the contraction or squeezing of the heart during a heartbeat. Thus, people who have survived a heart attack are often left with poor heart function (e.g. congestive heart failure).
Stem cell researchers have begun to question whether heart tissue destroyed during a heart attack is necessarily gone forever. Research is beginning to show that stem cells given after myocardial infarction are able to improve the squeezing power of the heart. By extension, stem cell treatment is able to improve the abilities heart to pump blood throughout the body.
Researchers initially assumed that it was the stem cells themselves that became new heart cells, replacing dead and dysfunctional heart tissue. While there is evidence that this occurs, it seems that stem cells play an even bigger role in heart tissue repair than simply becoming new heart cells. Stem cells release small packets of a material called exosomes and microvesicles. Exosomes and microvesicles hold proteins, cytokines, chemokines, growth factors, DNA, messenger RNA, and micro RNA. Researchers now believe that these materials hold the true power of stem cells in cardiac repair and regeneration.
Various types of stem cells produce exosomes that could potentially help repair a damaged heart. While cardiac stem cells may seem like an obvious source for these exosomes, induced pluripotent stem cells and mesenchymal stem cells are also capable of releasing exosomes that are potentially beneficial in cardiac repair.
Stem cells—or more accurately the exosomes contained within the stem cells—help repair damaged heart tissue in several ways. Stem cell-derived exosomes contain factors that promote the survival of vulnerable heart cells and cells that are dysfunctional after a heart attack (but not dead). Exosomes also help new blood vessels to form in and around the damaged heart muscle in a process called angiogenesis. These new blood vessels deliver oxygen, nutrients, and molecules that help support the growth and function of heart tissue. Exosomes also appear to promote a healthy immune system response after a heart attack, rather than a destructive inflammatory reaction. In other words, the materials found in exosomes guide the immune system to clear away damaged tissue without creating extensive fibrotic (i.e., tough, nonfunctional) tissue.
While most clinical trials thus far have studied the effects of stem cells directly infused into humans after myocardial infarction, exosomes are rapidly becoming the focus of future clinical trials in this area.
by admin | Sep 24, 2018 | Stem Cell Research, Stem Cell Therapy
The application of stem cells to treat health disorders, diseases, and injuries has been rapidly expanding in recent years. The breadth of their application comes from the fact that stem cells are undifferentiated and can, therefore, differentiate into all sorts of cells with different specialized functions and therefore have an enormous number of potential ways that they can improve health. A review published in Frontiers in Physiology covers the way stem cells can be used for therapy of oral diseases.
According to the authors of the article, adult stem cells and induced pluripotent stem cells are the best types of stem cells to use to treat oral and maxillofacial defects. There are pros and cons associated with adult stem cells, including both autologous and allogeneic stem cells, as well as with induced pluripotent stem cells. For instance, whereas autologous stem cells can modulate the immune system, allogeneic stem cells appear helpful for malignant diseases, and induced pluripotent stem cells are unlimited in terms of their source and do not involve any ethical issues.
There are a number of potential sources for treating oral disease, including tooth germ progenitor cells, dental follicle stem cells, salivary gland stem cells, stem cells of the apical papilla, dental pulp stem cells, inflamed periapical progenitor cells, among others. While adults stem cells can differentiate directly into specialized cells or can be turned into induced pluripotent stem cells, induced pluripotent stem cells can be driven to differentiate into specialized cells.
Clinical trials have been undertaken to study the ways in which stem cells can address a number of oral diseases, including bone diseases, dental pulp diseases, eye diseases, facial diseases, and periodontal diseases, as well as tooth extraction. The strategies for treating oral disease with stem cells involve sorting and expanding the stem cells outside of the body, mixing them with materials and factors that help them grow, and implanting them into the impaired region.
Future research will help to delineate the different ways in which certain types of stem cells can best be used to address individual oral diseases. Studies will also help to uncover the specific types of stem cells that are best for specific diseases and the protocols that should be used to reap the greatest benefits for patients.
by admin | Sep 13, 2018 | Stem Cell Research, Stem Cell Therapy, Studies
Patients usually recover from bone fractures with the right treatment, but sometimes the bone fails to heal because new tissue does not form and connect the broken pieces properly. Delayed union refers to cases where the bone takes longer than usual to heal, and nonunion refers to cases where the bone does not heal. In approximately 5 to 10 percent of cases of a fractured bone, delayed union or nonunion occurs. These conditions are associated with long-term pain and discomfort, and though can be addressed through surgical treatments, these interventions do not always lead to long-term healing.
In recent years, researchers have begun exploring the potential for mesenchymal stem cells to help address these important challenges of delayed union and nonunion. A review of the potential for these stem cells to help in these cases where fractures do not properly heal was recently published in the Journal of Biomedical Materials Research.
Mesenchymal stem cells are helpful in bone healing because they differentiate well and can differentiate into different cell lineages that are all important for bone formation, growth, and maintenance. These cell types include chondrocytes, osteoblasts, myoblasts, and adipocytes.
According to the authors of the review, mesenchymal stem cells can be used in conjunction with extracellular matrix scaffolds and biological adjuvants that promote growth, differentiation, and blood vessel formation, to help in the bone healing process when the delayed union or nonunion occurs. Future research will help to determine the best ways that mesenchymal stem cells can be used in combination with bioengineering strategies to help patients whose bone fractures do not heal or do not heal properly.
by admin | Sep 5, 2018 | Hyperbaric Oxygen Therapy, Stem Cell Research, Stem Cell Therapy, Studies, Traumatic Brain Injury
Traumatic brain injury (TBI) is one of the most common causes of disability in the United States, affecting over 13 million citizens. Traumatic brain injury is responsible for over 2 million emergency department visits, over a quarter of 1 million hospitalizations, and nearly 60,000 deaths each year.
Traumatic brain injury harms brain tissue in two phases. The first phase of injury occurs at the time of the traumatic incident. This initial injury may cause small or large areas of the brain to bleed. It may also shear (stretch/tear) nerve cells, making them dysfunctional. The second phase occurs hours or days after the initial injury. The brain is subjected to ongoing damage because of inflammation, cell death, and injury to blood vessels. Many people with TBI are left with lifelong problems with thinking, memory, and behavior.
In both of these phases of injury, one major way to help prevent long-term brain damage is by maintaining adequate blood flow to brain tissue. Unfortunately, once the damage has occurred, it can be a challenge to reverse the damage. Patients usually must endure months or years of physical and occupational therapy to regain what was lost. Moreover, patients often need substantial amounts of psychiatric and psychological support to treat mental health problems.
Fortunately, researchers are using hyperbaric oxygen therapy (HBOT) to improve blood flow to the brain in patients with traumatic brain injury. Hyperbaric oxygen therapy provides patients with pure oxygen (100%) at slightly higher pressures than they would experience normally. It is been used for hundreds of years to treat scuba divers who suffered “the bends” or decompression sickness; however, researchers are finding that hyperbaric oxygen therapy is a “coveted neurotherapeutic method for brain repair.”
To study the effects of hyperbaric oxygen therapy, researchers selected 10 people who had suffered mild traumatic brain injury in the previous 7 to 13 years. Patients all had brain damage that interfered with attention, memory, and thinking abilities.
Even though patients had sustained traumatic brain injury and brain damage a decade earlier, hyperbaric oxygen therapy was able to improve blood flow in the brain. Likewise, the amount of blood detected within the brain significantly increased, suggesting that hyperbaric oxygen therapy actually caused blood vessels in the brain to grow and multiply. Just as impressively, patients with chronic brain damage performed better on tests of cognition (i.e. thinking). They were able to process information more quickly, they had better motor function, and they were able to take in and process information about the world around them more efficiently.
Because people with traumatic brain damage have limited treatment options to improve their situations, these results are incredibly exciting. This was a study on 10 patients and more studies on larger numbers are still needed to build on these findings. Nonetheless, these results are quite encouraging for people with traumatic brain injury and their loved ones.
by admin | Aug 31, 2018 | Stem Cell Research, Stem Cell Therapy, Studies
Crohn’s disease is a chronic inflammatory bowel disease that has no cure. It causes abdominal pain, frequent diarrhea, weight loss, fatigue, and anemia. While the disease can be controlled to some degree through oral and injectable medications, life-threatening complications may occur.
One of the feared complications of Crohn’s disease is called a bowel fistula. A fistula is an abnormal connection between two places on the body. In Crohn’s disease, a fistula forms between the intestine and some other structure—the intestine essentially forms a “tunnel.” The fistula can form between one loop of intestine and another, between intestine and bladder, or even between the intestine and the outside of the body. This complication of Crohn’s disease is obviously quite distressing to patients.
Some bowel fistulas may close on their own with conservative treatments, but fistulas associated with Crohn’s disease do not respond well to available medical treatments. Those looking for an alternative treatment may be able to consider stem cell therapy.
Stem cells offer an interesting potential solution to this problem. Stem cells can provide a large dose of normal cells filled with molecules that can help direct normal bowel growth and development. Indeed, researchers have shown that autologous mesenchymal stem cells can help close and heal fistulas in patients with Crohn’s disease.
In phase I, II, and IIB clinical trials, stem cells derived from adipose tissue or bone marrow were directly infused into the bowel area (via a so-called intra-fistular injection). Across five clinical studies including over 100 patients, stem cell administration resulted in complete fistula healing in 50 to 80% of patients treated. Of those who did not obtain complete control fistula closure, almost all had evidence of improvement. These results support that autologous mesenchymal stem cell therapy is a promising future treatment for patients with Crohn’s disease and may offer patients enjoy a better quality of life.
by admin | Aug 28, 2018 | Stem Cell Research, Stem Cell Therapy
The evidence for the promise of mesenchymal stem cells in regenerative medicine has been growing for several years. With new sources regularly emerging, stem cells can come from a large variety of sources. Postnatal mesenchymal stem cells appear to have the most promise in regeneration. A new review has addressed how mesenchymal stem cells can be used with innovative scaffolding engineering approaches to improve techniques in regenerative medicine.
Mesenchymal stem cells are, on their own, good candidates for regeneration because of a number of characteristic features. For instance, they can differentiate into many different types of cells. Osteoblasts and chondroblasts are two cell types that mesenchymal stem cells differentiate into and that can be supported in bone regeneration by 3D-printed biomaterials like scaffolds.
Mesenchymal stem cells also can have beneficial impacts on the immune system. Unlike with other stem cell types, the severe immune reactions that may occur with the transplantation of foreign materials into the body can often be avoided with the use of mesenchymal stem cells, making them a safe option in regenerative medicine.
The current review addresses the ways in which bone regeneration can be optimized through the use of mesenchymal stem cells and scaffold engineering and how new concepts in bioengineering may be able to improve regenerative medicine in combination with mesenchymal stem cell approaches. Future research will need to focus on how we can customize regenerative approaches using what we know about mesenchymal stem cells and the most cutting-edge innovations in bioengineering.
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