What Is the Main Function of Mitochondria?
The main function of mitochondria, which are organelles also known as the powerhouse of the cell, is to produce energy. While they’re present in the thousands in each cell of the body, the exact number varies in different cell types. They are responsible for generating 90 percent of the energy that we need for all other functions of the body. They use the oxygen that we inhale and convert the nutrients of food into energy.
The other functions of mitochondria include:
- Apoptosis (programmed cell death): Apoptosis is a natural process in which the cells die. Mitochondria help decide which cells should die.
- Storing calcium: Mitochondria hold the calcium ions and release them when needed.
What are mitochondrial diseases?
Mitochondrial diseases include the conditions in which the mitochondria cannot perform their primary function of producing energy properly. They are primarily genetic conditions, which means there is some problem in the genetic makeup of the person that makes these conditions run in families. Therefore, you may get the gene for mitochondrial dysfunction from one of your parents.
One in 5,000 people have genetic mitochondrial diseases. Nearly 1,000 to 4,000 children in the United States every year are born with dysfunctional mitochondrial DNA passed from mother to offspring.
When mitochondria do not function properly, the cells do not get their energy. Hence, the cells do not function the way they should.
Depending on the organ affected by the mitochondrial disease, symptoms of the disease vary greatly, which may include:
- Loss of muscle coordination
- Muscle weakness
- Muscle pain
- Exercise intolerance
- Problems with vision
- Hearing issues
- Learning disabilities
- Heart disease
- Liver disease
- Kidney disease
- Gastrointestinal problems
- Swallowing difficulties
- Diarrhea or constipation
- Unexplained vomiting
- Abdominal cramps
- Neurological problems
- Poor growth
- Delays in development
- Increased risk of infection
- Movement disorders
- Thyroid problems
- Difficulty breathing
- Memory issues
Other conditions in which mitochondrial functioning may be affected include:
- Parkinson’s disease
- Alzheimer’s disease
- Bipolar disorder
- Schizophrenia
- Chronic fatigue syndrome
- Huntington’s disease
- Autism
- Diabetes
How are mitochondrial diseases diagnosed?
Mitochondrial diseases are difficult to diagnose, largely because there is no single laboratory test or imaging test to diagnose them.
The doctor will examine the person’s complete medical and family history. They will perform complete physical and neurological examinations and order a few of the tests that include:
- Blood tests
- Urine tests
- Cerebrospinal fluid tests or spinal tap (removal of fluid present around the spinal cord from your back)
- Magnetic resonance imaging or spectroscopy
- Retinal exam or electroretinogram
- Electrocardiogram or echocardiogram
- Audiogram or auditory brainstem-evoked responses
- Genetic analysis
- Skin biopsy
- Muscle biopsy
How are mitochondrial diseases treated?
Currently, there is no cure for mitochondrial diseases. However, treatment can help alleviate symptoms or improve quality of life.
Treatment of mitochondrial diseases varies among people and may include:
- Vitamins and supplements
- Exercises
- Supportive therapies
- Speech therapy
- Physical therapy
- Respiratory therapy
- Occupational therapy