WHY DO WE GROW OLD?

AGING PROCESS:

Danish research scientists are heading a large scale European research project on the aging process – and on how life quality can be increased when we grow old

The only thing we know for certain after we are born, is that we will die at some time in the future. The moment a child is born, an aging process begins which inexorably leads to the individual’s mortal decay and extinction. The body consists of a large number of different cells, and each of these cells age at different speeds. As cells age and die, new cells are created. The body can be thought of as a gigantic demolition and construction site with a constant supply of new bricks and mortar to rebuild the parts of the structure that break down.

“Life from birth to death is an amazing biological process which we actually know extremely little about,” says senior lecturer Peter Kristensen of the Department of Molecular Biology at the University of Aarhus. “We know a lot about the diseases which afflict us throughout life. Diseases which can be a result of the aging process. But when it comes to the natural degradation process, then in reality we don’t know that much.”

Natural aging
Now something is being done about that. The Department of Molecular Biology at the University of Aarhus has been chosen to head a large EU-financed research project to provide new insight into the complex process of aging. Not aging as a result of disease, but as Peter Kristensen says, the natural aging process.

The research is being conducted at molecular level through quantification of proteins, determination of how individual proteins interact, how they change over time and how proteins form part of a large, continuously renovated structure.

Proteins
“The aging process is enormously complex because the degradation of cells is affected by many factors,” says Peter Kristensen. He has a coordinating role in the project entitled “Functional Analysis of Evolutionarily Conserved Mechanisms of Aging Based on Advanced Proteome Analysis” known for convenience as PROTEOMAGE.

 “Environment, eating habits, physical activity, psychological and physical conditions are among the huge range of factors

which affect how, and especially how fast, we age. To deepen our understanding of this complex interplay, we need to begin with the basic building blocks of life, the cell and its protein components.”

Life quality
The Danish led research project involves 19 research groups in various European countries and one group in China. In addition to the PROTEOMAGE project, the EU has initiated a number of other projects in ageing research which includes cell energy research. Another project aims to collect and process genetic material from 2,800 European sibling pairs, all of whom must be alive and older than 90 years.

“The essential idea of the large scale project is not so much to find ways in which we can prolong life. But rather to discover how we can improve the quality of the time during which we live and naturally age,” says Peter Kristensen. “One of the potential outcomes of the project is for example a considerable improvement in diagnostics. If for instance we could predict rheumatoid arthritis in a person 10-20 years in advance, then treatment could be started which will improve life quality significantly.”

Recycling waste proteins
One of the processes which fascinates Peter Kristensen, and which will become an important part of the PROTEOMAGE research project, is the ability of cells to eliminate and reuse waste proteins which then help to prolong cell life.

“A cell consists of millions of different proteins which individually or in collaboration with others decide our development,” says Peter Kristensen. One of these protein complexes functions as a waste collector for all the others. Over time lots of the proteins in the cell decay, but then the waste collector comes into play. The protein works almost like a waste grinder. All waste proteins are chopped up into individual parts, which then are reformed into new building blocks in the cell – a genuine case of recycled waste. The process goes on all the time, but as time passes the cells gradually become less able to eliminate waste proteins, which then accumulate inside the cell. Eventually, the cell dies when the waste grinder can no longer keep up because of age. That is – metaphorically– what happens when we age.”

“What we are seeking to understand is how and why the many different proteins communicate,” says Peter Kristensen. “And here the waste grinder plays an important role. If we can gain insight into its complexities, then perhaps we can find the blueprint for a long and also healthy life.”