HIV infection is no longer a death sentence. Due to antiviral therapy, those infected can live a long life. However, the virus continues to exert biochemical changes on the human body and the overall effect is to “age”‘ the body.
The ageing carries risks. Medical scientists are now less concerned about diseases caused by a weakened immune system, and more about cardiovascular disease, neurocognitive impairment, and liver problems.
Research into the effects is based on epigenetics. Epigenetics is concerned with how environmental factors impact the genetics of an individual. The science extends to how environmental factors that switch genes on and off affect how cells read genes. For example, epigenetic changes can change DNA but not the actual DNA sequence. Once a change occurs, the effects can be passed through successive generations. The main way this is detected is through methylation, which describes how chemical groups are attached to DNA. Alterations to this affect protein expression.
Through studying methylation, scientists can use variations as a biological marker to look for signs of ageing. Such analysis was recently extended to patients with HIV. Here 137 people were analysed from the CHARTER (the CNS Antiretroviral Therapy Effects Research study) project. In addition, 44 people who did not have HIV were included as a comparator.
It was found that HIV infection led to a typical advance in biological aging of just under 5 years. This can be expressed as an increased chance of mortality of 19 percent (which is due to a rise in age related illnesses.) Interestingly, the length of time of HIV infection made no difference to the ageing effect.
Knowing this will lead to further research and an investigation as to whether the effects can be blocked through drug treatment.
The research has been published in the journal Molecular Cell. The research paper is titled “Methylome-wide analysis of chronic HIV infection reveals five-year increase in biological age and epigenetic targeting of HLA.”