Male fertility plays a paramount role in the process of conceiving a child. Couples are seen to experience infertility when a couple has regular and unprotected intercourse for a period of 12 months or longer and no pregnancy has occurred. It is advised that both parties get tested to determine where the problem might be. Looking at males, there are various factors that can affect their fertility where one rising factor is the effect of oxidative stress on a male’s reproductive health.
What is Oxidative Stress?
Various studies have proposed that when an imbalance occurs between reactive oxygen species (ROS) and the antioxidant defence system, it creates an environment where oxidative stress can increase and lead to disruptions in the normal sperm parameters that can affect a male’s fertility. Studies have also shown that oxidative stress is a major cause of unexplained male infertility. Reactive oxygen species are chemical compounds that contain oxygen atoms. In balanced amounts, the ROS play a role in the development of sperm properties which allows sperm to function optimally and give them the ability to fertilise a female’s egg. In excessive amounts, the ROS can cause sperm injury, disturbing sperm function and decreasing a male’s fertility.
Antioxidants
The human body has an antioxidant defence system where antioxidant enzymes protect cells and prevent damage to cells caused by oxidative stress. Various factors can alter the antioxidant defense system leading to an increase in oxidative stress. Some of these factors include, but are not limited to physical exercise, exposure to high-heat environments, exposure to environmental factors such as chemicals, deficiency in antioxidant properties within the body and even immune system disruptions. High levels of oxidative stress can cause tissue injury and eventually lead to cell death, playing an important role in the inflammation process within the body and can also cause altercations within the reproductive system.
There are various food sources that contain exogenous antioxidants. These food types can be consumed in order to reduce oxidative stress. Some of the antioxidants include:
- Ascorbic Acid: it is also known as vitamin C which can be found in citrus fruits and strawberries.
- Vitamin E: It can be found in vegetable oils, nuts and seeds.
- Carotenoids: These are pigments in plants which consist of antioxidant properties and are found in orange and red vegetables like carrots and tomatoes, as well as in green leafy vegetables such as kale and spinach.
- Polyphenols: These are found in plant material and are present in various forms. These are found in food types such as fruits and vegetables (berries, kale) as well as in legumes (beans) and nuts.
- Trace elements: Trace elements include zinc, selenium, copper and manganese. Zinc is one trace element that is known to have a positive effect on a male’s fertility due to its antioxidant properties and can be found in seafood and whole grains.
Impact on Sperm DNA
Oxidative stress significantly affects male fertility by inducing DNA damage in sperm heads. Reactive oxygen species can alter sperm DNA, leading to impaired DNA integrity, and potentially influencing offspring genetic conditions and sperm function.
Mitochondrial Dysfunction
Oxidative stress adversely affects sperm mitochondria, the energy source crucial for sperm motility. Damaged mitochondria result in decreased energy production, impairing sperm's ability to reach and fertilize the egg.
Protein Oxidative Modification
Oxidative stress can lead to protein oxidative modifications in sperm, hindering their optimal function in penetrating and fertilizing the egg. Such modifications disrupt sperm function and reduce their ability to enter the female egg, further impacting fertility.
Diagnosis And Treatment
Oxidative stress can be measured in humans to determine if it might have negative effects on a male’s health and reproductive health. Oxidative stress is diagnosed by means of a blood sample. This sample will be used to measure the amounts of reactive oxygen species or detect the levels of antioxidants present. Scientists working in a laboratory can also measure oxidative stress in an indirect manner by measuring the damage to lipid molecules, DNA, RNA or protein molecules.
High levels of oxidative stress can be managed with non-pharmacological approaches. Oxidative stress is usually alleviated by consuming antioxidants such as fruits and vegetables that are high in antioxidant properties. Other antioxidant supplementation can be found in pharmacological compounds such as Coenzyme Q10 and vitamin C supplements.