Research Digest

Lab notes: New method to rejuvenate aged stem cells to make them suitable for transplantation

This research has the potential to improve the outcome of regenerative medicine therapies.

Bone marrow transplantation involves transplantation of hematopoietic stem cells or those stem cells that give rise to other types of blood cells. In such cases, age of the donor is important as younger donor age results in better outcome. A group of Indian scientists have now developed a mechanism that can rejuvenate stem cells from older donors, making them useful for transplantation.

The mechanism developed by researchers at the National Centre for Cell Science, Pune involves rejuvenating aged hematopoietic stem cells in a short-term culture using micro-vesicles secreted by young stromal cells. This approach, they hope, will expand donor cohort.

The finding has relevance in clinical bone marrow transplantation, wherein usually aged donors are not preferred as their stem cells could have compromised engraftment ability due to aging. With the new mechanism it might be possible to rejuvenate aged stem cells and thereby expand donor pool.

“Stromal cells are support cells present in the micro-environment of stem cells,” explained Dr Vaijayanti P Kale, who led the research team. “We have shown that these cells display activated AKT signalling as they age. This leads to a loss of autophagy-inducing mRNAs in their micro-vesicles. If this signalling is blocked by using chemical inhibitors in aged stromal cells in culture, they become ‘young-like’ and secrete good quality micro-vesicles containing autophagy-inducing mRNA that can rejuvenate aged stem cells.”

The findings have been published in scientific journal Stem Cells.

For the study, researchers used 6‐8 weeks (young) and 18‐24 months (aged) old mice because age‐associated changes in human hematopoietic stem cells are similar to those observed in mouse, suggesting that hematopoietic aging is an evolutionarily conserved process. Their bone marrow derived lineage-negative cells were treated with extracellular vesicles, micro-vesicles or exosomes isolated from conditioned medium of mesenchymal stromal cells for 36 hours. The output cells were subjected to phenotypic, functional and molecular characterizations. They observed that young mesenchymal stromal cells rejuvenate aged hematopoietic stem cells.

“Our data indicates that such rejuvenation may also be possible for other tissue-specific stem cells. We propose to extend our research towards stem cells from other tissues,” said Kale. She also added that this research has the potential to improve the outcome of regenerative medicine therapies using this approach.

The research team included Rohan Kulkarni, Manmohan Bajaj, Suprita Ghode, Sapana Jalnapurkar and Dr Lalita Limaye.

This article was first published by India Science Wire.

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Following a mountaineer as he reaches the summit of Mount Everest

Accounts from Vikas Dimri’s second attempt reveal the immense fortitude and strength needed to summit the Everest.

Vikas Dimri made a huge attempt last year to climb the Mount Everest. Fate had other plans. Thwarted by unfavourable weather at the last minute, he came so close and yet not close enough to say he was at the top. But that did not deter him. Vikas is back on the Everest trail now, and this time he’s sharing his experiences at every leg of the journey.

The Everest journey began from the Lukla airport, known for its dicey landing conditions. It reminded him of the failed expedition, but he still moved on to Namche Bazaar - the staging point for Everest expeditions - with a positive mind. Vikas let the wisdom of the mountains guide him as he battled doubt and memories of the previous expedition. In his words, the Everest taught him that, “To conquer our personal Everest, we need to drop all our unnecessary baggage, be it physical or mental or even emotional”.

Vikas used a ‘descent for ascent’ approach to acclimatise. In this approach, mountaineers gain altitude during the day, but descend to catch some sleep. Acclimatising to such high altitudes is crucial as the lack of adequate oxygen can cause dizziness, nausea, headache and even muscle death. As Vikas prepared to scale the riskiest part of the climb - the unstable and continuously melting Khumbhu ice fall - he pondered over his journey so far.

His brother’s diagnosis of a heart condition in his youth was a wakeup call for the rather sedentary Vikas, and that is when he started focusing on his health more. For the first time in his life, he began to appreciate the power of nutrition and experimented with different diets and supplements for their health benefits. His quest for better health also motivated him to take up hiking, marathon running, squash and, eventually, a summit of the Everest.

Back in the Himalayas, after a string of sleepless nights, Vikas and his team ascended to Camp 2 (6,500m) as planned, and then descended to Base Camp for the basic luxuries - hot shower, hot lunch and essential supplements. Back up at Camp 2, the weather played spoiler again as a jet stream - a fast-flowing, narrow air current - moved right over the mountain. Wisdom from the mountains helped Vikas maintain perspective as they were required to descend 15km to Pheriche Valley. He accepted that “strength lies not merely in chasing the big dream, but also in...accepting that things could go wrong.”

At Camp 4 (8,000m), famously known as the death zone, Vikas caught a clear glimpse of the summit – his dream standing rather tall in front of him.

It was the 18th of May 2018 and Vikas finally reached the top. The top of his Everest…the top of Mount Everest!

Watch the video below to see actual moments from Vikas’ climb.

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Vikas credits his strength to dedication, exercise and a healthy diet. He credits dietary supplements for helping him sustain himself in the inhuman conditions on Mount Everest. On heights like these where the oxygen supply drops to 1/3rd the levels on the ground, the body requires 3 times the regular blood volume to pump the requisite amount of oxygen. He, thus, doesn’t embark on an expedition without double checking his supplements and uses Livogen as an aid to maintain adequate amounts of iron in his blood.

Livogen is proud to have supported Vikas Dimri on his ambitious quest and salutes his spirit. To read more about the benefits of iron, see here. To read Vikas Dimri’s account of his expedition, click here.

This article was produced by the Scroll marketing team on behalf of Livogen and not by the Scroll editorial team.