FERTILITY DYSFUNCTION
 R.A.S HEMAT, MB;BCh, FRCSI, Dip.Urol.UCL.
Little is known about reproductive dangers of chemicals. Abnormal sperm occurs more common in men living in polluted cities. Pesticides cause over a 3- to 8-fold increase in sperm abnormalities. Abnormal sperm occurs more often in males exposed to chemicals during the two month sperm development period before conception.
- Male fertility dysfunction (FD) is a multifactorial disease process with a number of potential contributing causes. High levels of free radicals can damage sperm cells directly. An exess of reactive oxygen species (ROS) impairs sperm cell function and play a negative role in male factor fertility. Defective sperm function is associated with the overproduction of ROS by abnormal spermatozoa and leukocytes. Varicocele is the most common treatable cause of infertility in men.
The majority of men with varicocele have an abnormal spermiogram, and varicocele repair improves sperm quality and subsequently increases pregnancy rates. Mechanisms of infertility in varicocele: 1- Induction of testicular hypoxia by venous stasis and small vessel occlusion leading to Leydig cell and germinal cell dysfunction. 2- Retrograde flow of adrenal and renal metabolites from the renal vein down the left internal spermatic vein. 3- Elevation in scrotal temperature. 4- Depression of gonadotropin or androgen secretion, which may change the endocrine environment to which both testes are exposed. 5- Excessive formation of ROS, with oxygen metabolite most damaging to human spermatozoa being H2O2. Reactive oxygen species (ROS) initiate the peroxidation of unsaturated fatty acids in the sperm plasma membrane resulting in a loss of motility and the capacity of sperm-oocyte fusion. ROS can be generated by the spermatozoa themselves or phagocytic leukocytes. 6- Nitric oxide (NO) is capable of inhibiting human sperm motility. NO can reduce ATP and thus decrease sperm motility. NO derives from several cells of the male genital system such as phagocytes, endothelial cells and smooth muscle cells. Peroxynitrite is a noxious oxidant formed by a rapid reaction between NO and superoxide. Nitric oxide synthase (NOS) and xanthine oxidase activities in blood of varicocele veins are greater than those in peripheral blood, resulting in a dramatic increase in the rate of NO, peroxynitrite and S-nitrosothiol release within the varicocele veins. There is a 25 fold increase of NO rate production in the varicocele vein. This NO may derive from the cells of the varicocele vein (endothelial or smooth muscle cells) or from the NOS that has been diffused out of the varicocele vein. NO may also be produced by the testis and accumulate within the spermatic vein. ROS and fatty acid peroxides generated by ROS exert their action on spermatozoa by increasing lipid peroxidation and depletion of ATP. Moreover, the degradation products of these fatty acids peroxides may also be toxic to spermatozoa. NO decrease sperm motility by a mechanism involving inhibition of cellular respiration resulting in depletion of sperm ATP.
Conditions for conception to occur:
1- The testes must have normal spermatogenesis.
2- The spermatozoa must complete their maturation.
3- The ducts for sperm transport must be patent.
4- The prostate and seminal vesicles must supply adequate amounts of seminal fluid.
5- The coital technique must enable the male partner to deposit his semen near the female cervix.
6- The spermatozoa must be able to penetrate the cervical mucus and reach the uterine tubes.
7- The spermatozoa must undergo capacitation and the acrosome reaction, fuse with the oolemma, and be incorporated into the ooplasm.
Orchiectomy and radiotherapy have a considerable sexual problems including low sexual drive, ED and decreased intensity of orgasm. Libido is decreased in about 50% of patients for just 2-3 months after orchiectomy. Testosterone replacement may allow normal sexual function resume.
May, 2008
The information in this article has been excerpted from the following books: ANDROPATHY, by R.A.S. HEMAT.
Note: Permission is granted to copy and redistribute this document electronically as long as it is unmodified. This article may not be sold in any medium, including electronic, CD-ROM, or database, or published in print, without the explicit, written permission of Dr. R. A. S. Hemat.
Clinical Orthomolecularism Classroom
Dr. R.A.S HEMAT declares no conflicts of interest or financial interests in any product or service mentioned in this article, including grants, employment, stock holdings, gifts, or honoraria.
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