Science Bites seeks to compile the latest scientific research updates in bite-sized forms.

1. Umbilical cord stem cells to treat heart failure

Patients with heart failure may benefit from stem cell infusions. In a phase 1/2 randomised controlled trial, 30 patients between the age 18 and 75 with stable and optimally treated heart failure were subject to a single IV infusion of umbilical cord-derived mesenchymal stem cells (UC-MSC) or placebo.

Patients who received the stem cell infusion showed significant improvements in left ventricular ejection. These results were sustained even at 12 months after the infusion. No adverse effects were noted in the patients who received the stem cell infusions. These patients also reported better quality of life.

How do stem cells help in heart failure? Pre-clinical studies on UC-MSC showed that they are able to differentiate into cardiomyocyte-like cells and are able to enhance cardiac function and offer cardiomyocyte protection. Furthermore, UC-MSC is more easily harvested compared to bone-marrow derived stem cells, the latter having been subject to intense research in heart failure for more than a decade.

Heart failure is a debilitating condition that affects about 26 million people. The 10-year survival rate is projected to be less than 30%.

“Standard drug-based regimens can be suboptimal in controlling heart failure, and patients often have to progress to more invasive therapies such as mechanical ventricular assist devices and heart transplantation,” says lead author Jorge Bartolucci.

"We are encouraged by our findings because they could pave the way to a non-invasive, promising new therapy for a group of patients who face grim odds," says study corresponding author Fernando Figueroa. Both are faculty members of the Universidad de los Andes in Chile.

2. Stem cells as treatment for lung damage and asthma

Stem cell therapy could treat damaged lung cells (bottom right). Photo credit: Imperial College London/MedicalXpress
Stem cell therapy could treat damaged lung cells (bottom right). Photo credit: Imperial College London/MedicalXpress

A team of researchers from Imperial College London and Hong Kong University have demonstrated that stem cells may be able to alleviate damage dealt by cigarette smoke to lung cells.

Mice that were subject to ozone therapy (results in similar damage seen in chronic obstructive pulmonary disease, COPD) were treated with a single peripheral infusion of stem cells. The treated mice displayed reduced lung inflammation in the lung at 24 hours post-injection.

Researchers postulate that these stem cells exert their beneficial effects by combating oxidative stress in lung cells. Smooth muscle cells in human lung tissue cultures that have been exposed to cigarette smoke have been observed to exhibit more free radicals. Free radicals then go on to cause oxidative stress, leading to damage and premature mitochondrial apoptosis in lung cells.

Having said that, it is important to note that cigarette smoke may damage lung cells via other molecular mechanisms, such as inflammation. “This study shows that some of detrimental effects of cigarette smoke or ozone can be alleviated in the cells and whole animal, by treatment with stem cells. What our work provides is the potential for cell-based therapies for one aspect of COPD – oxidative stress,” says Dr Pank Bhavsar, one of the lead researchers in the study.

Researchers infer that asthma patients may stand to benefit from stem cell therapy, as it has similar molecular patterns of disease to COPD. Further research is also required to determine a more effective means of delivering stem cells to the damaged area, and to further explore the mechanisms of how stem cells repair diseased cells.



3. Water level in stem cells influencing differentiation fate

Top images (A): Illustrates the development of stem cells on hydrogel, a soft substrate, to pre-bone cells after the removal of water. Bottom images (B): Depicts the development of stem cells on glass, a hard substrate, to pre-fat cells after the addition of water. Photo credit: Research team/Science Daily
Top images (A): Illustrates the development of stem cells on hydrogel, a soft substrate, to pre-bone cells after the removal of water. Bottom images (B): Depicts the development of stem cells on glass, a hard substrate, to pre-fat cells after the addition of water. Photo credit: Research team/Science Daily

Manipulating the water content in a stem cell has the power to alter the differentiation pathway that it takes. Such was the conclusion drawn by a group of researchers from Buffalo University, the Massachusetts Institute of Technology (MIT) and Harvard University, US.

“Volume has been considered as a well-controlled property of cells… We wondered if the water amount in cells also varies in response to different environmental cues, thus changing the mechanical property of the cell,” comments lead author Professor Ming Guo.

Mouse mesenchymal stem cells (MSCs) normally differentiates into pre-bone cells when added into a mix of neutral culture and hard substrate that mimics the cellular environment of bone. Interestingly, when researchers changed the culture condition (without removing the ‘bony environment’ substrate) to a hypotonic one, these same MSCs tended to differentiate into pre-fat cells.

Stem cell behaviour has long been known to be regulated by their chemical and physical environment. The results of this study raised the possibility that direct alteration of inherent cellular characteristics of volume and stiffness may also affect the fate of a stem cell.

“The findings from this study add a fascinating new tool to our understanding and utilization of stem cell biology for regenerative medicine," states co-author Dr Praveen Arany. MIMS

Read more:
4 latest stem cell research and applications
Scientists implicate stem cells in invasive tumours
Stem cell transplant aids in recovery of stroke patients

Sources:
https://www.medicalnewstoday.com/articles/319552.php
https://www.sciencedaily.com/releases/2017/09/170926162309.htm
http://circres.ahajournals.org/content/circresaha/early/2017/09/15/CIRCRESAHA.117.310712.full.pdf
https://medicalxpress.com/news/2017-09-stem-cells-patients-lung-copd.html
http://www.genengnews.com/gen-news-highlights/manipulating-water-content-in-stem-cells-influences-differentiation-fate/81254977
https://www.sciencedaily.com/releases/2017/09/170926125131.htm