The aim of our study was to investigate the relationships between the expression of leptin, leptin receptor in the testis and spermatogenesis, and testosterone (T) concentration in infertile men. Testicular tissue samples were collected from the testes of five fertile volunteers, eight patients with obstructive azoospermia (OA), six patients with Sertoli cell-only syndrome (SCO) and 32 oligospermic patients with varicocele testis. In testicular tissue, leptin and leptin receptor were identified by staining with polyclonal antibodies. Serum follicle stimulating hormone, lutenising hormone (LH), and T were determined by chemiluminescence assays. Leptin was expressed on germ cells, mainly on spermatocytes. The ratio of immunostained germ cells to total germ cells was inversely correlated with the concentration of T (r = -0.32, P = 0.01), sperm concentration (r = -0.51, P = 0.002) and Johnsen's score (r = -0.44,P = 0.005). In contrast, leptin receptor immunostained cells were found in the interstitium, primarily in Leydig cells. Leptin receptor expression on Leydig cells was inversely correlated with serum T concentration (r = -0.50, P < 0.001). The dysfunction of spermatogenesis is associated with an increase in leptin and leptin receptor expression in the testis.

Ghrelin, which is the endogenous ligand for the growth hormone (GH) secretagogue receptor (GHS-R), has been primarily linked to the central neuroendocrine regulation of GH secretion and food intake, although additional peripheral actions of ghrelin have also been reported. Recent research has suggested that ghrelin also affects testosterone (T) secretion in vitro. To investigate the role of ghrelin in human testicular function, we examined the expression of ghrelin in testicular tissues by immunohistochemistry. Testicular tissue samples were collected from the testes of 5 fertile volunteers, 8 patients with obstructive azoospermia, and 36 oligospermic patients with varicocele testis. In the testicular tissues, ghrelin was stained using the antighrelin polyclonal antibody, and the Johnsen sco re w as ca lcu la te d. Th e con cent ra ti on s o f ser um follicle-stimulating hormone (FSH), lutenizing hormone (LH), and T were determined by chemiluminescence assays. Immunostaining of ghrelin was detected in the interstitium and in Leydig cells. Ghrelin expression by Leydig cells was inversely correlated with the serum T concentration (r 5 2.50; P , .001), but was not directly related to spermatogenesis. We conclude that steroidogenic dysfunction is associated with increased ghrelin expression in human testes.Key words: Leydig. J Androl 2007;28:320-324 G hrelin has recently been identified as the endogenous ligand for the growth hormone (GH) secretagogue receptor (GHS-R) (Kojima et al, 1999; Kojima et al, 2002). Ghrelin is a 28-amino acid peptide with an essential n-octanoyl modification at Ser3. This peptide is primarily expressed in the stomach and hypothalamus (Kojima et al, 1999; Kojima et al, 2002). As expected for an endogenous ligand of GHS-R, ghrelin elicits GH secretion in vivo and from anterior pituitary cells in culture (Kojima et al, 1999;Takaya et al, 2000;Wren et al, 2000). In addition to its role in the control of GH release, ghrelin, probably derived from a stomach source and acting on hypothalamic centers, has recently been shown to induce a number of biological responses at the central neuroendocrine level, including stimulation of food intake and adiposity (Kamegai et al, 2000;Takaya et al, 2000;Wren et al, 2000). The biological effects of ghrelin identified to date are executed at the central levels of the hypothalamus and pituitary. In addition to these central biological effects, there is growing evidence for peripheral actions of ghrelin. In this regard, the novel expression of ghrelin in noncentral tissues, such as the ovary and kidney, is of interest (Tschop et al, 2000;Gaytan et al, 2003).Moreover, it has been shown that ghrelin and its functional receptor are expressed in rat and human testes Tena-Sempereet al, 2002; Gaytan et al, 2004). Testicular function is critically dependent upon the interaction of a plethora of endocrine, paracrine, and autocrine regulatory signals (Skinner MK, 1991;Saez JM, 1994). It has become evident that different factors with key roles in growth axis...

The clinical features of patients with Klinefelter's syndrome attending a male infertility clinic have been investigated in order to consider their assisted reproduction treatment options. Over 12 years, a total of 148 patients with sterility due to azoospermia had Klinefelter's syndrome. Eight patients were shown by fluorescence in-situ hybridization (FISH) on metaphase spreads to be mosaic (46,XY/47,XXY), and 140 patients showed only 47,XXY. Small testes were observed in 95% of patients and gynaecomastia was seen in 12.4%. Half of the patients showed hypergonadotrophic hypogonadism, while others showed normogonadism (usually hypergonadotrophic). Spermatozoa were observed in semen from one patient with mosaicism and one without. Three-colour FISH revealed hyperploidy in 2.7% and 2.3% of these spermatozoa respectively. Multiple-site testicular biopsies in five recent patients were performed and yielded a specimen with round and elongated spermatids in one patient with 47,XXY karyotype. This sample was cryopreserved for future intracytoplasmic sperm injection. At follow-up, 46% of couples had chosen artificial insemination with donor sperm, and none had chosen adoption. Two patients developed testicular tumours, one a mature teratoma and the other a Leydig cell tumour. Two patients required androgen replacement therapy.

RESULTSThe mean ( SD ) sperm concentration and Johnsen's score in the varicocele group was lower than in the normal group, at 27.6 (11.8) vs 80.4 (21.7) million/mL ( P < 0.001) and 7.6 (1.1) vs 9.0 (0.7), respectively ( P < 0.05). In all patients, 8-OHdG was mainly expressed in the spermatogonia and spermatocytes in the seminiferous tubule. Immunostained germ cells correlated negatively with sperm concentration ( r = − 0.48, P = 0.01) and Johnsen's score ( r = − 0.46, P = 0.02), but not with folliclestimulating hormone, luteinizing hormone or testosterone level. Immunostained germ cells were significantly more prevalent in the varicocele group, at 53.6 (5.7)%, than that in the normal group, at 14.3 (2.3)% ( P < 0.001). The prevalence of immunostained germ cells and clinical grades were positively related; the ratio recorded for varicocele grades I, II and III was 38.0 (10.0)%, 41.0 (9.1)%, and 57.0 (9.3)%, respectively (grade I vs grade III, P < 0.05). CONCLUSIONSIncreased 8-OHdG expression in the testis was associated with deficient spermatogenesis in infertile men with varicocele.

testosterone, prolactin and oestradiol), testicular volume, and the diameter of the seminiferous tubules, were evaluated. Patients were categorized into groups according to Johnsen score, i.e. group 1 ( < 4), group 2 ( ≥ 4 and < 6) or group 3 ( ≥ 6). The clinical variables were compared in each group. RESULTSHormone levels in almost all patients were in the normal range. FSH was related to the stage of MA; the difference in FSH between groups 1 and 3 was significant ( P = 0.006). Serum levels of LH, testosterone, prolactin or oestradiol were similar in all groups. The diameter of the seminiferous tubules was less in group 1 than in group 3 ( r = 0.881, P < 0.001) and there was an inverse and linear correlation between the FSH concentration and the diameter of the seminiferous tubules (r = -0.661, P = 0.0028). CONCLUSIONSFSH is the most useful variable for evaluating the severity of MA, even when it is within the normal range. The finding that gonadal hormone concentrations are normal in patients with MA suggests that an abnormality other than a disturbance in the hypothalamo-pituitary-testicular axis is responsible for MA.