Less sugar, please! New studies show why diabetics lose muscle mass faster

KEY STORY

• Earlier, research by Ottawa Hospital Research had proved that people who keep their skeletal muscles toned tend to live longer, healthier lives. Now researchers from the Tokyo Metropolitan University have shown that skeletal muscle satellite cells, key players in muscle repair, proliferate better in low glucose environments.

  What are satellite muscle cells:

  

• Satellite cells are a type of stem cell that, when they divide, produce either new satellite cells or myoblasts, which grow to become muscle cells. They can also go into a state of dormancy if the body deems them unnecessary due to a sedentary lifestyle. Skeletal muscle satellite cells reside between the two layers of sheathing, the sarcolemma and basal lamina and envelop myofiber cells in individual muscle fibres.

  The recent finding by the scientists at the Tokyo Metropolitan University team of researchers is contrary to the conventional wisdom that says mammalian cells fare better when there is more sugar to fuel their activities.

  The team now believes that since ultra-low glucose environments do not allow other cell types to proliferate, it could produce pure cultures of satellite cells, potentially a significant boost for biomedical research.

  How muscle repair works at the cellular level:

  1. With the wear and tear of everyday use, muscles continuously repair themselves to keep them in top condition.

  2. When myofiber cells are damaged, the satellite cells go into overdrive, multiplying and finally fusing with myofiber cells.

  3. This not only helps repair the damage but also maintains muscle mass.

  Medical science is still trying to understand how muscle loss happens due to illness, inactivity, or age, and what are the specific mechanisms involved.

  A team of scientists from Tokyo Metropolitan University led by Assistant Professor Yasuro Furuichi, Associate Professor Yasuko Manabe and Professor Nobuharu L Fujii have been studying how skeletal muscle satellite cells multiply outside the body.

  Looking at cells multiplying in petri-dishes in a growth medium, they noticed that higher levels of glucose had an adverse effect on the rate at which they grew. This is counterintuitive; glucose has, all along, been considered essential for cellular growth. It is converted into ATP, the fuel that drives a lot of cellular activity. Yet, the team confirmed that lower glucose media led to a larger number of cells, with all the biochemical markers expected for greater degrees of cell proliferation.

  Muscle cells are different:

  1. They also confirmed that this doesn’t apply to all cells.

  2. So was the amount of glucose in their original experiment somehow “just right?”

  3. The team added glucose oxidase, a glucose-digesting enzyme, to get to even lower levels of glucose, and grew the satellite cells in this glucose-depleted medium.

  4. Shockingly, the cells seemed to fare just fine and proliferated normally. The conclusion is that these stem cells seem to derive their energy from a completely different source. Their further research is to try and pin down what this is.

  Sugar levels in diabetics:
  The team notes that the sugar levels used in previous experiments matched those found in diabetics. This might explain why the loss of muscle mass is seen in diabetic patients and may have significant implications for how we might keep our muscles healthier for longer.

  Disclaimer: Tips and suggestions mentioned in the article are for general information purpose only and should not be construed as professional medical advice. Always consult your doctor or a dietician before starting any fitness programme or making any changes to your diet.