The length of time that it takes for wounds like cuts and scrapes to heal is determined by a person’s age. This phenomenon has been recorded as far back as World War I, but the reason behind it was recently discovered. Sadly, wounds cannot be healed with a simple kiss. The process of wound healing is extremely complex. It involves intricate communication between the skin and immune cells via cell signaling pathways. The beginning of the process triggers the formation of a scab, which acts as a protective barrier for the skin. Skin cells called keratinocytes later travel beneath the scab to fill in the space and heal the wound. The keratinocytes at the edges of the wound also tell immune cells to help fill the gap by producing special proteins known as skints. This speeds up the healing process.
Why is Healing Delayed in the Elderly?
Recent studies by scientists at Rockefeller University have shown that in elderly people, this process is slowed due to a delayed communication between skin cells and immune cells. They did this by studying two-month-old mice compared to two-year-old mice, which is equivalent to comparing twenty-year-old and seventy-year-old humans. They discovered that the keratinocytes in older mice took much longer to travel to the wound area. They also learned that keratinocytes in the elderly do not signal for the immune cells to assist in filling the wound gap. Without this added healing speed, it takes longer for wounds to close. The researchers hope to use these discoveries to develop drugs that will enhance communication between skin cells and immune cells.
Editor: Rachel Levy