Specific aspects of erectile dysfunction in endocrinology.

Prominent diseases of the endocrine system, such as diabetes mellitus, hypogonadism, and hyperprolactinemia, may cause erectile dysfunction (ED). ED affects about 50% of male diabetic patients possibly due to the vascular and neuropathic complications. Metabolic control and selective phosphodiesterase type 5 inhibitors are therapies of choice for controlling ED. By correcting hypogonadism, testosterone levels are restored. This, and the use of dopaminergic drugs, which normalize prolactin levels in male hyperprolactinemia, may be effective in reversing ED in these endocrine disorders.

Prospective study of the enzymatic activities in urine of N-acetyl-beta-D-glucosaminidase, alpha-D-mannosidase, alpha- and beta-D-glucosidases, alpha-L- and beta-D-fucosidases, and beta-D-galactosidase in type I diabetes mellitus with early nephropathy.

Different surveys have been carried out on the plasma activities of different glycosidases in patients with insulin-dependent diabetes mellitus, but research on urinary glycosidases in this disease is scanty and incomplete. To elucidate the behavior of these lysosomal enzymes in the metabolic alterations occurring in the glomerular basal membrane during the initial stages of diabetic nephropathy, we conducted a prospective study to examine the urinary activities of N-acetyl-beta-D-glucosaminidase (NAG), alpha-D-mannosidase, alpha- and beta-D-glucosidase, alpha-L- and beta-D-fucosidase, and beta-D-galactosidase in patients with type I insulin-dependent diabetes mellitus, surveyed over 18 months, whose early diabetic nephropathy was detected by the presence of microalbuminuria. The simultaneous determination of beta 2-microglobulin in urine confirmed the glomerular origin of the albuminuria. No statistically significant correlation was found between the levels of albuminuria and the activities of any of the glycosidases analyzed. In the diabetic patients, a significant decrease was observed in the activities of all the enzymes (p < 0.05), except NAG and alpha-D-mannosidase, although the decrease in the latter was very close to statistical significance (p = 0.028, unilateral; p = 0.057 bilateral). Similarly, in the patients, there was a significant negative correlation (p < 0.05) with the serum levels of fructosamine, except with beta-D-galactosidase, which showed a positive correlation (p < 0.05) with fructosamine and blood HbA1c.(ABSTRACT TRUNCATED AT 250 WORDS)

Enzymatic glycosidase activities in experimental obesity.

Glycosidases are lysosomal enzymes that participate in the catabolism of glycoproteins and other glycoconjugates, and in some way may modify their activity in situations in which carbohydrate metabolism could be altered, such as the case of obesity. Using a fluorometric assay, a study was made of four glycosidase activities: N-acetyl-beta-D-hexosaminidase (NAG), alpha-mannosidase and alpha- and beta-glucosidase in the serum, pancreas, liver and kidney of 22 Zucker fa/fa genetically obese rats and of 23 fa/? controls, both with ages ranging between 13 and 15 weeks. After 12-14 hours fast and prior anaesthesia with sodium pentobarbital intraperitoneally, blood and the afore-mentioned organs were removed for enzymatic study of the serum and the organs after homogenization and centrifugation. In the serum a statistically significant increase in alpha-mannosidase (p < 0.0001) and alpha-glucosidase (p < 0.02) activities was found in the fa/fa obese rats as compared with the controls. No statistically significant differences were found in serum hexosaminidase activity between the two groups, and no serum beta-glucosidase enzymatic activity was detected. In liver, a decrease was observed in hexosaminidase (p < 0.002) and alpha-glucosidase (p < 0.01) activities in the obese rats as compared with the controls. In whole pancreas an increase was found in alpha-glucosidase activity in the obese rats with respect to the controls (p < 0.001), with no statistically significant differences in the hexosaminidase, alpha-mannosidase and beta-glucosidase activities.(ABSTRACT TRUNCATED AT 250 WORDS)

Enzyme and hormonal markers in the differential diagnosis of human azoospermia.

The serum concentrations of FSH, LH, prolactin, testosterone, and estradiol and the enzymatic activities of hyaluronidase, glucosidases (alpha-glucosidase, beta-glucosidase, alpha-mannosidase, N-acetyl-beta-D-glucosaminidase, beta-glucuronidase, and beta-galactosidase), lactate dehydrogenase and its isoenzymes (LDH1, LDH2, LDH3, LDH-X, LDH4), and total proteins were measured in the semen of 69 subjects (8 normozoospermic controls, 7 secretory, and 54 excretory azoospermic subjects). FSH levels rose with the deterioration in spermatogenesis and served to differentiate the secretory from the excretory azoospermias. The only source of hyaluronidase and LDH-X in the ejaculate is the spermatozoa. alpha-Glucosidase activity essentially originates in the epididymis. The seminal determination of alpha-glucosidase and, to a lesser extent, alpha-mannosidase and N-acetyl-beta-D-glucosaminidase helps rapidly, sensitivity, reliably, and noninvasively to differentiate secretory azoospermias (with higher enzymatic activity) from the excretory type (less enzymatic activity) and may be of use in identifying with a certain degree of reliability the site of obstruction in the male genital tract.

[Sertoli-Leydig-cell ovarian tumor with a retiform pattern and heterologous elements: a rare cause of virilization]. / Tumor ovárico de células de Sertoli-Leydig con patrón retiforme y elementos heterólogos: una rara causa de virilización.

The case is presented of a young female with virilization signs and total circulating testosterone levels above 4 ng/ml, without a concomitant increase in cortisol, 17 OH-progesterone, DHEA-S, or androstenedion levels. On CT scan exam a tumoral mass in the left ovary was observed with polycystic characteristics similar to those observed in ovarian cystadenoma, inspite of the fact that most androgenic ovarian tumors are solid. The pathological study revealed an ovarian Sertoli-Leydig tumor associated to a reticular pattern with heterologous chondroid and mucinoid elements of cystadenoma.

Semen characteristics and diabetes mellitus: significance of insulin in male infertility.

A study was made of semen quality and serum hormonal profiles (FSH, LH, prolactin, testosterone) of patients with type I diabetes mellitus. Semen parameters and levels of prolactin and testosterone were significantly altered in the diabetic state. The concentration of insulin in serum and seminal plasma and the serum levels of FSH, LH, and testosterone were measured in 80 men classified in the following groups: fertile subjects, infertile normoglycemic subjects, subjects with carbohydrate intolerance, and excretory and secretory azoospermic subjects. In all groups, seminal insulin concentrations were higher than those obtained in serum. The hormone appears to freely cross the blood-testis barrier, there to be concentrated in the semen. The levels of insulin in serum and seminal plasma did not correlate with semen parameters and are not suitable markers of seminal quality. For unknown reasons, the concentrations of insulin in seminal plasma were lower in the subjects suffering from carbohydrate intolerance.

Primary hypothyroidism and human spermatogenesis.

Spermatogenic function was studied in 10 patients, previously diagnosed as having primary hypothyroidism, in whom a state of hypothyroidism has been induced by discontinuation or a decrease in treatment with levothyroxine over at least one spermatogenic cycle. Most of the patients had fathered children before the study. When the results obtained in the hypothyroid state were compared with those from a group of 16 controls with proven fertility, slight anomalies were observed; these were characterized by a decrease in seminal volume (p less than 0.05), progressive forward motility (p less than 0.01), and the cumulative percentage of mobile forms (p less than 0.01). There were no anomalies in sperm density or in the percentage of spermatozoa with normal morphology. No alterations in circulating levels of testosterone and gonadotropins existed. Induction of hypothyroidism did not lead to seminal or hormonal modifications compared with the same patients in a situation of euthyroidism. Short-term postpuberal hypothyroidism did not cause seminal alterations sufficiently intense to induce male infertility.

Androgen environment and beta-glucuronidase activity in the human kidney.

Basal beta-glucuronidase activity was measured in the cytosol of renal cortex in 10 women and nine men, and its levels were correlated to the concentrations of the main circulating androgens and to the cytoplasmic androgen receptor content. beta-Glucuronidase activity in women was similar to that found in men, despite blood testosterone levels being higher in the latter. The activity of the enzyme does not appear to be related to circulating levels of either testosterone or androstenedione. Only in men the androgen receptor content and dehydroepiandrosterone-sulphate levels were inversely correlated to beta-glucuronidase. In the human kidney cytosol there is no evidence of sexual dimorphism in basal beta-glucuronidase activity; whereas the total testosterone circulating levels do not seem to control the enzyme activity.

Urinary kinetics of triiodothyronine and their modification with aging.

The urinary kinetics of triiodothyronine (T3) in healthy young and old people has been studied. The behavior of urinary excretion is similar in both age groups, expressed in our mathematical model in the cumulative kinetics as well as in the urinary rate. However, a significant decrease (P less than 0.025) of renal clearance of T3 in elderly individuals has been found. No significant differences (P greater than 0.05) were observed in any other kinetic parameters. The possible influence of the reduction of glomerular filtrate has been discussed as the most important pathogenic factor of the decreased renal clearance of this hormone. Possibly, modifications of the distribution volumes are also involved. Due to the limited number of persons studied, for ethical reasons, the results obtained are not definitive.

Seminal plasma leucine aminopeptidase in male fertility.

Leucine aminopeptidase (LAP) enzymatic activity has been measured in the seminal fluid of a group of 119 males undergoing fertility check-up, and correlated with spermatic density. The results indicate that there exists a direct correlation between LAP activity in the seminal plasma and spermatic density. However, differences between the groups considered according to spermatic density are not significant. Seminal plasma mean leucine aminopeptidase is 40 times higher than that found in blood plasma.

Serum glycosidases in diabetes mellitus in relation to the retinopathy and to the length of the disease.

The following glycosidase activities in sera have been studied: alpha-D-mannosidase, beta-D-glucuronidase, N-acetyl-beta-D-galactosaminidase, alpha-D-galactosidase, beta-D-galactosidase, alpha-D-glucosidase, beta-D-glucosidase and beta-D-fucosidase, in diabetic patients in relation to the presence of microangiopathy, evident by retinopathy, and to the length of the disease. A significant increase of all the enzyme activities, except for alpha-D-galactosidase was found. These elevations were independent of the development of retinopathy and the duration of the diabetic process.