Gonadotropin-releasing hormone and the lungs
Gonadotropin-releasing hormone (GnRH) medications are used to treat a wide range of reproductive disorders. GnRH regulates not only the maturation and growth of the gonads, but also the immune system and metabolism, thereby affecting non-reproductive, somatic tissues. GnRH affects the lungs, but research findings are limited and not generalized. The aim was to summarize the effects of GnRH on the lungs based on a literature review. Results . The presence of specific receptors for GnRH (GnRHR) in various lung cells and in the cells of some forms of cancer allows the use of GnRH-agonists and antagonists for the treatment of pulmonary disease and for both malignant tumors and their metastases to the lungs, especially those originating from the reproductive organs. The presence of GnRHR in tumor cells impels binding GnRH both to antitumor drugs for their targeted delivery and to magnetic nanoparticles for magnetic resonance imaging of cancer. Various forms of cytostatics conjugated with GnRH are less toxic and more effective than the cytostatics themselves. A large surface area with good vascularization and the ability to exchange various substances allow for systemic delivery of GnRH via inhalation into the lungs. Inhalation administration of anticancer drugs associated with a GnRH analogue is promising for the treatment of lung cancer with GnRHR expression. One of the pulmonary complications that develops when using both GnRH analogues and antagonists is interstitial lung disease, which can lead to death. An increased risk of classical pneumonia has been described after androgen deprivation therapy. Also, GnRH can enhance the development of lung pathology during radiation exposure. However, some publications report the absence of negative effects of GnRH on the pulmonary system in the experiments and in clinical practice and report that an increased level of GnRH even protects the lungs from edema and inflammatory damage, reduces the severity of sclerosis and fibrosis. Pulmonary macrophages, type 1 and 2 alveolar cells can be directly involved in the degradation of GnRH and have the necessary enzyme complexes. Conclusion . The obvious scarcity and inconsistency of publications on all aspects of GnRH action on the lungs indicates the need for further continuation of not only applied research, but also fundamental research, due to the high prospects. The GnRH drugs have advantages and disadvantages. Hormonal therapy should be prescribed with caution, taking into account all indications and contraindications, as well as the endocrinologist’s experience, aiming for the most favorable long-term result.