Recent data from animal models suggests that alcohol and drugs of abuse directly influence changes in gene expression in areas of the brain that help drive memory and reward responses.

For example, alcohol can cause an alternative form of a gene to be expressed in the memory circuits in flies and people, resulting in changes in dopamine receptors and transcription factors involved in reward signaling and neuronal function. Similarly, cocaine can cause an alternative form of a gene to be expressed in the reward centers of mice, leading them to seek out more cocaine.

Alcohol, nicotine, cocaine and opioids also all activate important signaling pathways that are central regulators of metabolism. This suggests they can also affect many aspects of neuronal function and consequently affect which genes are expressed.

Many commonly prescribed medications for mental health disorders also affect gene expression. Antidepressants and mood stabilizers can change how DNA is modified and which genes are expressed. For example, a commonly prescribed drug for depression called escitalopram affects how tightly wound DNA is and can change the expression of genes important to brain plasticity.

Additionally, mRNA-based therapies can specifically change which genes are expressed to treat diseases like cancer. In the future, we may discover similar therapies for alcohol and substance use disorder. These treatments could potentially target important signaling pathways linked to addiction, altering how brain circuits function and how alcohol and drugs affect them.

Like alcohol and drugs, dietary changes can affect gene expression in many ways. In flies, a high sugar diet can reprogram the ability to taste sweetness by tapping into a gene expression network involved in development.

Intensive meditation, even after only one day, can also affect gene regulation in your brain through similar mechanisms. Attending a monthlong meditation retreat reduces the expression of genes that affect inflammation, and experienced meditators can reduce inflammatory genes after just one day of intensive meditation.

Work in animal models has also shown that exercise changes gene expression by altering both histones and the molecular tags directly attached to DNA. This increases the activity of genes important to the activity and plasticity of neurons, supporting the idea that exercise improves learning and memory and can decrease the risk of dementia.