Infertility is a major problem affecting people medically and psychosocially. The number of infertile couples is on the increase. More worrisome is that the number of men presenting with low sperm count is on the increase. In Nigeria, this problem affects one out of five men.
Oxidative stress has long been identified as having an influence on health, including men’s fertility level. Experts believe oxidative stress causes a number of undesirable effects on the body. It damages DNA, a problem that could lead to cancer, and is linked with ageing and infertility.
It is impossible to completely avoid oxidative stress, also known as free-radical damage. This is because it happens every time the body cells are exposed to oxygen – and cells need oxygen. When molecules inside cells come into contact with oxygen, it “oxidises” them, causing them to lose an electron and become unstable. These unstable molecules can go on to damage components of the cells in the body such as the DNA and cell membranes.
Sperm, like other cells in the body are constantly facing the oxygen-paradox because they are rich in polyunsaturated fatty acids (PUFA) and thus, they are very susceptible to oxidative stress attack which results in decrease sperm motility.
Fortunately, there are things that can be done to reduce the amount of oxidative stress that sperms and other body cells are exposed to such as higher consumption of fruits and vegetables. Fruits and vegetables are rich in chemical substances, which are natural antioxidants that counteract the effects of free radicals that cause oxidative cell damage.
Experts, however, believe that African walnut is one of nature’s remedy to infertility in men arising from oxidative stress. An assessment of extract of African walnut leaves in laboratory animals found that it has compounds with radical scavenging abilities that is protective of the cells of the penis and testes.
The study, published in the 2015 edition of BMC Complementary and Alternative Medicine, was carried out by Seun F Akomolafe, Ganiyu Oboh and Afolabi A Akindahunsi from the Federal University of Technology, Akure, Ondo State in collaboration with Anthony J Afolayan at the University of Fort Hare, Alice, South Africa.
The researchers suggested that the extract can be used as an alternative remedy to synthetic antioxidants in combating the effects of oxidative stress.
African walnut, which is scientifically called Tetracarpidium conophorum, is a climbing shrub that is locally cultivated mainly for the nuts which are cooked and consumed as snacks. It is locally used by the elderly people for the treatment of constipation. The amino and fatty acids components of the nut are used for the treatment of prolonged and constant hiccups.
The barks are used in coffee as laxative and also chewed to reduce toothache. The leaves, bark and fruit of the plant are used medicinally and their uses include toothache, eczema, common cold and prostate cancer
Also, in West Africa the leaves are used as male fertility agent and in the treatment of dysentery.
Previous studies have shown African walnut seeds to have significant effect on testosterone and oestradiol levels, sperm motility, testes and epididymides weight of the rats treated with various doses of the seed powder.
This research, which was titled: investigating the effects of Tetracarpidium conophorum seeds on the hormone and sperm profile of male albino rats, involved 48 albino rats of about twelve weeks. The test extract was obtained from the seeds and incorporated into the feed of the rats.
The results, published in the 2014 edition of the Annual Research & Review in Biology, indicate that the African walnut seeds can enhance the production of reproductive hormones and may be used in the formulation of useful fertility drugs.
They declared: “Though the seed extract of T. conophorum did not have significant effect on the testosterone, there was an observed difference on the sperm viability among rats in the different groups which could probably be as a result of the presence of vitamin E in the extract, a known male fertility agent.
“This increase in sperm count might also not be unconnected with the presence of bioactive component such as vitamin E and zinc in the extract. It could be possible that the antioxidant potential of vitamin E in the seeds must have played a major role in scavenging free radicals that might accumulate to reduce the number of sperm cells thereby leading to an increase in the sperm counts. There was also significant effect of the test substance on the sperm head abnormalities.
Conversely, dietary plants such as water extract of Moringa oleifera and Newbuoldia laevis Leaves, scientists have found helpful in curtailing the effect of oxidative stress on male fertility.
Moringa oleifera, commonly called horse radish or drumstick tree is known by many native names in Nigeria such as zogalle (in Hausa), okweoyibo (in Igbo) and ewe igbake (in Yoruba). It is well known for its nutritional as well as medicinal values by many communities in Northern Nigeria.
Medicinally, the plant is well known for its use in the treatment of hypertension, ulcer, and infertility control. Also, its leaves is used as vegetable in soup preparation or cooked and mixed with grounded groundnut cake and other spices.
Newbuoldia laevis, commonly known as African Border tree, Aduruku or Bareshi(Hausa), Ogirisie (Igbo) and Akoko (Yoruba) is used for therapeutic purpose against a number of diseases. In Ivory Coast and Nigeria, stem bark decoctions of N. laevis is used for the treatment of epilepsy and convulsions in children. In Nigeria, decoctions of leaves and roots made from boiling are used in the treatment of breast tumours and improve male fertility.