Whirledge Shannon D, Garcia Jose M, Smith Roy G, Lamb Dolores J
Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas.
Division of Endocrinology, Diabetes, and Metabolism, Michael E. DeBakey Veterans Affairs Medical Center, Baylor College of Medicine, Houston, Texas.
Biol Reprod. 2015 Mar;92(3):76. doi: 10.1095/biolreprod.114.123570. Epub 2015 Jan 28.
The chemotherapeutic drug cisplatin causes a number of dose-dependent side effects, including cachexia and testicular damage. Patients receiving a high cumulative dose of cisplatin may develop permanent azoospermia and subsequent infertility. Thus, the development of chemotherapeutic regimens with the optimal postsurvival quality of life (fertility) is of high importance. This study tested the hypothesis that ghrelin administration can prevent or minimize cisplatin-induced testicular damage and cachexia. Ghrelin and its receptor, the growth hormone secretagogue receptor (GHSR-1a), are expressed and function in the testis. Targeted deletion of ghrelin, or its receptor, significantly increases the rate of cell death in the testis, suggesting a protective role. Intraperitoneal administration of vehicle, ghrelin, or cisplatin alone or in combination with ghrelin, in cycles of 9 or 18 days, to adult male C57Bl/6 mice was performed. Body weight was measured daily and testicular and epididymal weight, sperm density and motility, testicular histology, and testicular cell death were analyzed at the time of euthanization. Ghrelin coadministration decreased the severity of cisplatin-induced cachexia and gonadal toxicity. Body, testicular, and epididymal weights significantly increased as testicular cell death decreased with ghrelin coadministration. The widespread damage to the seminiferous epithelium induced by cisplatin administration was less severe in mice simultaneously treated with ghrelin. Furthermore, ghrelin diminished the deleterious effects of cisplatin on testis and body weight homeostasis in wild-type but not Ghsr(-/-) mice, showing that ghrelin's actions are mediated via GHSR. Ghrelin or more stable GHSR agonists potentially offer a novel therapeutic approach to minimize the testicular damage that occurs after gonadotoxin exposure.
化疗药物顺铂会引发多种剂量依赖性副作用,包括恶病质和睾丸损伤。接受高累积剂量顺铂治疗的患者可能会出现永久性无精子症及随后的不育症。因此,开发具有最佳生存后生活质量(生育能力)的化疗方案至关重要。本研究检验了如下假设:给予胃饥饿素可预防或减轻顺铂诱导的睾丸损伤和恶病质。胃饥饿素及其受体,即生长激素促分泌素受体(GHSR-1a),在睾丸中表达并发挥作用。靶向敲除胃饥饿素或其受体可显著提高睾丸中的细胞死亡率,提示其具有保护作用。对成年雄性C57Bl/6小鼠进行为期9天或18天的腹腔注射,分别注射溶媒、胃饥饿素、顺铂或顺铂与胃饥饿素联合用药。每天测量体重,并在安乐死时分析睾丸和附睾重量、精子密度和活力、睾丸组织学以及睾丸细胞死亡情况。联合给予胃饥饿素可减轻顺铂诱导的恶病质和性腺毒性的严重程度。随着联合给予胃饥饿素后睾丸细胞死亡减少,体重、睾丸和附睾重量显著增加。在同时接受胃饥饿素治疗的小鼠中,顺铂给药引起的生精上皮广泛损伤程度较轻。此外,胃饥饿素减轻了顺铂对野生型小鼠睾丸和体重稳态的有害影响,但对Ghsr(-/-)小鼠无效,表明胃饥饿素的作用是通过GHSR介导的。胃饥饿素或更稳定的GHSR激动剂可能提供一种新的治疗方法,以尽量减少性腺毒素暴露后发生的睾丸损伤。