Stimulation of protein synthesis in pachytene primary spermatocytes from the human testis by pyruvate

Enzymatic properties of adult human Sertoli cells in vitro

The adult human Sertoli cells produced lactate, estradiol-17beta, transferrin and inhibin; germ cells modulate synthesis of these compounds. In order to study the functional features of human Sertoli cells in vitro, the aim of this study was to measure the lactic dehydrogenase (LDH), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP) and creatine kinase activities (CK) in primary cultures of Sertoli cells prepared from young men (mean age: 29 years, n = 11). Five LDH isozymes have been found in Sertoli cells, the main fractions being the LDH3 and LDH4; each of them represented 30% of the total LDH activity. Furthermore, CK and ALP activities were measured in Sertoli cells. It is of note that the Sertoli cell ALP activity was 50% lower than that of germ cells. Whatever the Sertoli cell parameter measured herein, there is a great variability between patients and FSH (dbc AMP, as well as retinol, insulin, testosterone) is poorly effective in improving these enzymatic activities in vitro. We have confirmed that GGT was exclusively present in Sertoli cells and thus may be considered as a specific marker. LDH is involved in Sertoli cell glucose transformation and thus provided energetic substrates for germ cells. In contrast, the roles of CK and ALP remains to be clarified. In conclusion, we have demonstrated the existence of several enzymes namely LDH, GGT, ALP and CK in Sertoli cells prepared from adult human testis.

In vitro effects of psychoactive and non-psychoactive cannabinoids on immature rat Sertoli cell function

We have examined the effects of psychoactive and non-psychoactive cannabinoids on isolated immature rat Sertoli cells cultured in either serum-free or serum-containing media. Lactate accumulation by Sertoli cells in serum-free control cultures was 10 fold greater than the values obtained in control cultures exposed to serum. Under either culture condition, 3.1 micrograms/ml of delta-9-tetrahydrocannabinol (THC) or cannabinol (CBN) stimulated lactate secretion above control levels. Cannabidiol (CBD) stimulated lactate secretion in serum-containing but not in serum-free media. Using serum-free culture conditions, we next studied the in vitro effects of combinations of THC and either epinephrine or FSH on lactate and transferrin secretion by immature rat Sertoli cells. Co-incubation of 0.1 microM epinephrine with 0.8 or 3.1 microgram/ml THC significantly stimulated lactate secretion when compared to epinephrine or THC alone, while only the high THC dose increased transferrin secretion. Moreover, co-incubation of FSH (1 micrograms/ml) with THC (0.8 or 3.1 micrograms/ml), significantly stimulated both lactate and transferrin production by immature rat Sertoli cells. These results add to the growing evidence that cannabinoids can exert direct effects on Sertoli cell function and modulate their responses to physiological stimuli.