Caloric Restriction Fights Cells' Aging     

Caloric restriction studies have been implemented on rats recently. The team then focused on the cellular effects of rats after completing the implementations. Researchers find that this restriction can fight against aging on cellular levels.  

Eating less can benefit you with reducing inflammation in your body, delay age-related diseases, and ensure a long, healthy life. The research team comprises experts from the US, and China confirms this in their new study. The report they provide is full of detailed information on a calorie-restricted diet in rats and its effect on cellular levels. The report has been published in Cell on February 27, 2020. 

Juan Carlos Izpisua Belmonte is the senior author of this study paper who works as a professor in Salk's Gene Expression Laboratory. He says, "We already knew that calorie restriction increases life span, but now we've shown all the changes that occur at a single-cell level to cause that. This gives us targets that we may eventually be able to act on with drugs to treat aging in humans."

The hardest fact of human life is aging as it invites many diseases like diabetes, cancer, dementia, and other metabolic syndromes. Caloric restriction is fruitful in fighting age-related diseases as it is proved in animal models. The researchers know any organism's cells changes as it ages, but how these changes cope up with caloric restriction is unknown to them. 

Belmonte worked with three alumni of his Salk lab in this new research. His collaborators are working on their projects as they are now professors serving in China.  The team compared two groups of rats with different diets. One group had a full diet, and the other group was allowed to have 30% less diet than the previous group. They continued the process for nine months, and the rats were 18 months old when they started this project. This age range of rats can be compared to humans from 50 through 70.

As a part of their research, the team took 56 rats, chose 40 cell types from them, and finally analyzed 168,703 cells after completely isolating them. They took the cells from the aorta, brain, bone marrow, fat tissues, kidney, liver, muscle, and skin. The team used single-cell genetic-sequencing technology in each isolated cell for measuring genes' activity levels. Besides, they did not forget about the given tissues' overall composition of cell types. Later, they focused on each diet and compared them between the old and the young rats.

They found a significant variation between the two groups. The first group with a regular diet showed signs of changes as they grew older. But these changes were absent in the rats with restricted diets. They did not face changes even in their old age. Both groups got older at the end of the study. But the rats with restricted diets showed 43 percent fewer changes than that of the rats with a regular diet.  

Guang-Hui Liu works at the Chinese Academy of Sciences as a professor. As a co-corresponding author of the study, he says, "This approach not only told us the effect of calorie restriction on these cell types but also provided the most complete and detailed study of what happens at a single-cell level during aging."  

Diet is directly related to inflammation, immunity, and lipid metabolism. So, it influences cells and genes. While the team was studying nearly every tissue, they noticed a dramatic increase in the number of immune cells. Although the control rats aged, the rats with restricted diets remained unaffected from aging effects.  

Jing Qu shares the same position as Guang-Hui Liu in the study paper and the same profession at the Chinese Academy of Sciences. He says, "The primary discovery in the current study is that the increase in the inflammatory response during aging could be systematically repressed by caloric restriction." 

In the next step, the team focused on transcription factors, also known as the master switches. These switches can alter the activity of many other genes. Ybx1 is the one that stood alone at the time of alteration during caloric restriction. It is evident in 23 different cell types. Scientists believe that Ybx1 is the factor that protects age-related issues and is willing to perform more research on them.  

According to Concepcion Rodriguez Esteban, a principal author of this study, 'you are what you eat' is entirely accurate as it matches with the research. He says, "The state of your cells as you age depends on your interactions with your environment, which includes what and how much you eat."

The information from the report is vital in many ways, and scientists should use this to discover drugs against aging. They should also build-up strategies to increase lifespan.