Nerve Regeneration in Older Adults - An Overview

What Are Nerves?

A nerve is a bundle of fibers that transmits signals between the brain, spinal cord, and other parts of the peripheral nervous system. They control the body’s movement, touch, sensation, and pressure. Nerves comprise of sensory (afferent) and motor (efferent) neurons, which relay signals between the brain and other body parts.

What Are the Types of Nervous Systems?

There are two types of nervous systems. They are:

• Central Nervous System: The central nervous system comprises the brain and spinal cord. The brain performs the cognitive function of the individual. The spinal cord carries information from other body parts of the brain and vice-versa.

• Peripheral Nervous System: The peripheral nervous system lies outside the brain and spinal cord. It carries information from the brain to other parts of the body.

How Do Nerves Carry Information?

The nerve cells (neurons) are vital for transmitting information. Communication takes place through electrical signals within neurons, and they are called neurotransmitters.

What Is Nerve Degeneration?

Nerve degeneration refers to the progressive degeneration of the nerve cells due to lesions (damaged area). As there is a loss of structure and function, the information-carrying capacity of the nerves is reduced. This deterioration causes many diseases, cumulatively called “neurodegenerative diseases.”

What Is Nerve Regeneration?

Nerve regeneration is the regrowth or repair of nervous tissues, including neurons, which have been damaged due to injury or disease. The regeneration process is divided into nerve repair and nerve reconstruction.

• Nerve repair involves reconnecting the proximal (closer to the main body) and distal (further away from the main body) ends of a severed nerve.

• Nerve reconstruction involves the creation of new nerve tissue to compensate for a damaged, missing or dysfunctional nerve.

There are many steps in nerve regeneration, including axon growth, myelination, and synapse formation.

Is Nerve Regeneration Possible in Older People?

Yes, nerve regeneration is possible in older adults, but it may be slower due to age-related changes in their neurological system. In addition, physical therapy and various rehabilitation techniques may be necessary to facilitate this process.

What Are the Effects of Aging on the Nervous System?

The brain starts its functioning from the fifth week of gestation (time period of a baby in mother’s womb) until death. Brain functions are active during childhood, stable in adults and decrease in older people. The decrease in function is due to the changes in the brain chemicals or the changes in the nerve cells. Over time, the toxic substances accumulate and produce changes in the brain. The nerve impulses work at a slow pace affecting various functions of the brain.

Older people with reduced brain function usually complain of:

• Short-term memory loss.

• Difficulty in verbal communication.

• Impaired cognitive function.

• Peripheral neuropathy (a medical condition characteristic of loss of sensation or burning sensation).

• Numbness and tingling sensation.

• Muscle weakness.

• Loss of function.

• Sharp pain.

What Are the Disorders That Promote Reduced Brain Function?

Certain medical conditions, disorders and injuries to the nerve result in decreased nerve function. Some of them are:

• Stroke.

• Depression.

• High blood pressure.

• Hypothyroidism (reduced thyroid hormones).

• Cholesterol.

• Diabetes mellitus (high blood sugar).

• Accident.

• Injuries.

• Degenerative nerve diseases such as Alzheimer’s disease, Parkinson’s disease, and

Hutchinson’s disease.

How Is Nerve Injury Diagnosed?

The clinician or health care provider take a brief history of the symptoms, previous medications, surgeries, trauma, or accident, and conducts a physical and neurological examination. The other diagnostic aids recommended are:

• Electromyography (EMG): Electromyography is performed using a thin needle-like electrode inserted into the muscleto record the muscle’s electrical activity. The activity of the muscle, both in rest and motion, is recorded. In case of nerve damage, there is reduced muscle activity.

• Nerve Conduction Study: The electrodes are placed at two different points in the body to measure the speed of the impulses along the nerves.

• Magnetic Resonance Imaging (MRI): MRI uses a magnetic field and radio waves to produce images of the area affected by nerve damage.

• Ultrasound: Ultrasound images are produced using high-frequency sound waves. With the help of these images the affected area is diagnosed.

What Are the Possible Treatment Options?

Nerve injuries heal on their own through the process of regeneration. However, nerve regeneration happens at a slower pace. Therefore, several treatments can help to restore the nerve function.

• Braces and Splints: These devices align the affected area in a position to improve the function.

• Physical Therapy: Physiotherapy involves performing specific exercises or movements to keep the affected area active. Physiotherapy is a guided therapy where the physiotherapist analyzes the medical records and advises the appropriate exercises and body movements that improve neural synaptic functions.

• Walking: Walking maintains the range of motion and increases the blood supply. Increased blood supply heals the affected area.

• Supplements: Vitamins B6, B1, and B12 are beneficial in cases of neuropathy. They reduce the pain and preserve the covering of the nerves.

• Electrical Stimulators: They are placed on the affected muscles to stimulate the affected muscles; meanwhile, the nerves tend to regrow.

• Surgery: Surgery is the best option to restore function in extreme cases. A medical procedure is performed to remove the injured portion and make a new synaptic connection.

Can Neurodegenerative Disease Be Prevented?

Degenerative diseases cannot be prevented, but the risk factors and symptoms can be reduced by following certain steps.

• Active and Healthy Lifestyle: First, adopt a healthy lifestyle. Make walking a routine to maintain a healthy weight. Being active increases the blood flow by opening the collateral vessels.

• Take a Balanced Diet: Prefer eating a balanced diet so that certain deficiencies of vitamins and minerals are avoided.

• Alcohol Consumption: Avoid consumption of excess alcohol as it decreases brain function.

• Getting Proper Sleep: Deprived sleep is common in older adults. Changes in sleep patterns impair the cognitive function of the brain.

• Develop Hobbies: Develop hobbies that trigger the brain. Reading books and playing games like quizzes and puzzles triggers brain function.

• Maintain Social Connect: Connecting with a family member or friends digitally or in person helps maintain cognitive function.

What Could Be the Risk Factor That Promotes Neurodegeneration?

Apart from aging and family history, certain lifestyle modifications promote neurodegenerative diseases.

• A diet containing high amounts of fat and sugar.

• Nutrition deficiency.

• Physical inactivity.

• Lack of cognitive stimulation.

• Accumulation of toxic substances in the brain.

• Injuries.

• Obesity (especially central obesity - fat accumulation in the abdominal area).

Conclusion:

Nerve regeneration is the process of regrowth of damaged or injured nerve cells. While it was previously believed that nerve regeneration is not possible in older adults, recent research suggests that nerve regeneration is indeed possible, albeit at a slower rate than in younger individuals. Despite being slower and less efficient, studies have shown that nerve cells in older adults can still generate new nerve fibers and repair damaged nerve cells. Factors such as chronic health conditions, lifestyle choices, and genetics can affect the rate and extent of nerve regeneration in older adults.