Oligospermia is one of the important causes of male infertility, and pharmacological treatment is mainly aimed at low spermatogenic function due to testicular factors. At present, because the systemic theory of the pathogenesis of oligospermia has not been confirmed, the drug mechanism is still focused on the reproductive endocrine mechanism.
I. For hormonal drugs
These drugs are based on the fact that testosterone is necessary for spermatogenesis, and testosterone is regulated by luteinizing hormone in the pituitary gland. Follicle-stimulating hormone mainly acts on the supporting cells of the varicocele to synthesize and secrete androgen-binding protein, which is combined with testosterone to make sufficient concentration of androgens in the varicocele to facilitate spermatogenesis.
1.Gonadotropin-releasing hormone
Theoretically, gonadotropin-releasing hormone can act directly on the pituitary gland to promote pituitary gonadotropin production instead of using exogenous human chorionic gonadotropin or human menopausal gonadotropin to increase pituitary gonadotropin levels, but research on such drugs is currently scarce; GnRH may be valued as a promising drug in the future.
2. Gonadotropins
The early use of these drugs include HCG and HMG, but both have limited effects and serious side effects such as breast feminization and spermatogenesis disorders, so they have been less frequently reported recently. A recent randomized controlled trial showed that both FSH and LH can independently maintain spermatogenesis, but FSH is more effective in maintaining the number of spermatocytes at the crude line stage, while HCG can be used to treat the conversion to spermatocytes at the genetic level (i.e. as a substitute for LH).
3. Androgens
Testosterone undecanoate was used in the early stage, which has an effect on sperm maturation and gonadal stimulation. Since Adamopoulos proposed the use of testosterone undecanoate in combination with tamoxifen for the treatment of oligospermia, there have been few reports on androgen therapy.
4.Estrogen antagonists
The mechanism of action is that in the hypothalamus and pituitary gland competitive binding estrogen receptors, the negative feedback effect of estrogen is effectively inhibited, resulting in increased secretion of GnRH, FSH, LH, LH and other stimulation of interstitial cells to increase local testosterone production, which is conducive to spermatogenesis. Such drugs are clomiphene, tamoxifen, etc.
5.Aromatase inhibitors
Aromatase is a cytochrome P450 enzyme that can be present in the testes. The function of this enzyme is to convert testosterone to estradiol and androstenedione to estrone. In animal studies, percutaneous implantation of aromatase inhibitor capsules reduced the concentration of estradiol in seminal plasma, increased the concentration of testosterone, improved spermatogenesis and facilitated sperm production. The main drugs available for clinical use are: testosterone, anastrozole, letrozole, etc.
Other drugs
1.Anti-ROS drugs
These drugs include vitamin C, vitamin E and essential fatty acids. The mechanism is related to the scavenging of oxygen free radicals and antioxidant effect.
2.Carnitine
That is, vitamin Bt, which is an essential coenzyme in the tissue, carnitine in patients with oligospermia is lower than normal. L-carnitine combined with levacetylcarnitine can improve semen parameters and increase sperm vitality.
3.Chinese herbal medicine
Chinese herbal medicine has a promising future for the treatment of idiopathic oligospermia and azoospermia. According to TCM, the kidney harbors essence and is the master of reproductive development. Kidney yin and kidney yang are the two forms of kidney essence transformed into physiological effects, which will be maintained in a unified balance. When the kidney essence and kidney qi, kidney yang and kidney yin are deficient or deficient, the balance of kidney yin and yang is disrupted, then the male related reproductive pathological changes occur.
In conclusion, since the pathogenesis of oligospermia has not yet formed a complete systematic theory, most of the new therapeutic drugs developed so far are generated in exploring the mechanisms related to the etiology, therefore, in-depth research is needed to study the theory of the process of spermatogenesis and maturation and the disorders arising from different stages of spermatogenesis and maturation, and to develop more effective therapeutic drugs for each aspect of the pathogenesis. In addition, there are numerous applications and developments of Chinese medicine, but there is a lack of in-depth exploration of the mechanism of action, and there is a need to fill the gaps in the theory of action with modern medical methods.