Bruno Varriale

Professor Applied Biology

Name Bruno
Surname Varriale
Institution Università degli Studi della Campania Luigi Vanvitelli
E-Mail bruno.varriale@unicampania.it
Address Department of Experimental Medicine, Molecular Genetics Laboratory, University of Campania "Luigi Vanvitelli", Via Costantinopoli 16, 80138, Naples, Italy
Bruno Varriale

Member PUBLICATIONS

  • Seasonal fluctuations in plasma progesterone concentrations in Gentile-di-Puglia and Ile-de-France ewes in southern Italy.

    Publication Date: 01/07/1988 on Journal of reproduction and fertility
    by Dell'Aquila S, Varriale B, Alberico G, Pierantoni R

    Ile-de-France ewes had high plasma progesterone concentrations during early summer-late winter. Gentile-di-Puglia ewes had high progesterone values during the winter-spring-summer period but during autumn progesterone values were very low and oestrous behaviour was not displayed. The comparison with Ile-de-France ewes indicates that a phase shift occurs in the annual ovarian activity in ewes of the Gentile-di-Puglia breed.

  • Hypothalamus-hypophysis and testicular GnRH control of gonadal activity in the frog, Rana esculenta: seasonal GnRH profiles and annual variations of in vitro androgen output by pituitary-stimulated testes.

    Publication Date: 01/04/1988 on General and comparative endocrinology
    by Fasano S, Minucci S, Pierantoni R, Fasolo A, Di Matteo L, Basile C, Varriale B, Chieffi G

    The binding of a gonadotrophin-releasing hormone (GnRH) long acting analog (GnRHA), D-Ser (But)6,Pro9-NEt GnRH (HOE 766), to pituitary and testicular extracts and the presence of GnRH-like material in testes and hypothalamuses were measured in the frog, Rana esculenta. Also, the cellular localization of immunoreactive GnRH was investigated in testes by immunohistochemical staining. Furthermore, lyophilized preparations of pituitary crude homogenates from animals caught monthly were tested in vitro for their ability to stimulate androgen production by December testes. Satisfactory results on specific 125I-GnRH binding were difficult to obtain in view of its low binding capacity. Moreover, binding in testicular homogenates was of the same order of magnitude (about 2%) as that found in pituitaries. In a cospecific radioimmunoassay for GnRH nonapeptide, both hypothalamic and testicular extracts gave displacement parallel to the standard curve. Immunoreactive GnRH did not significantly fluctuate in hypothalamuses, while it peaked in testes during December and July. Immunoreactive GnRH was evidenced in June and September testes employing immunohistochemical staining. In particular, the interstitial cells and the Sertoli cells were faintly stained. Testes of December animals stimulated by February pituitaries produced larger quantities of androgens as compared with testes stimulated with hypophyseal preparations from the remaining periods of the year. In conclusion, the present results are consistent with the idea that seasonal changes of the hypothalamus-hypophyseal activity play an important role in regulating the hormonal response in vertebrate testes. Moreover, we report that, in addition to rats, GnRH-like material is present in frog testes and for the first time it has been shown that such putative intratesticular material undergoes seasonal fluctuations in a vertebrate.

  • Relationship between estradiol-17 beta seasonal profile and annual vitellogenin content of liver, fat body, plasma, and ovary in the frog (Rana esculenta).

    Publication Date: 01/03/1988 on General and comparative endocrinology
    by Varriale B, Pierantoni R, Di Matteo L, Minucci S, Milone M, Chieffi G

    The seasonal plasma estradiol-17 beta (E2-17 beta) profile and annual vitellogenin content of liver, fat body, plasma, and ovary were investigated in Rana esculenta. Concomitant with the increase in E2-17 beta, vitellogenin peaked in liver, plasma, and ovary during autumn and winter, while it remained at a relatively high concentration in fat body during spring. In vitro experiments showed that E2-17 beta (10(-9) M) is ineffective in inducing vitellogenin production in fat body, but is effective in inducing vitellogenin production in liver. As fat bodies do not produce the vitellogenin they contain, we suggest that fat bodies are involved in the transfer of vitellogenin to the ovary.

  • A gonadotropin-releasing hormone (GnRH) antagonist decreases androgen production and spermatogonial multiplication in frog (Rana esculenta): indirect evidence for the existence of GnRH or GnRH-like material receptors in the hypophysis and testis.

    Publication Date: 01/01/1988 on Endocrinology
    by Di Matteo L, Minucci S, Fasano S, Pierantoni R, Varriale B, Chieffi G
    DOI: 10.1210/endo-122-1-62

    The effects of a GnRH antagonist (GnRHA) on GnRH agonist (GnRH*)-induced androgen production and spermatogonial multiplication were studied in the frog, Rana esculenta, in vivo and in vitro. Intact and hypophysectomized (PDX) animals were kept at 22 +/- 2 C and treated with GnRH (45 ng/g BW) and GnRH* plus 1X and 10X concentrations of GnRHA on alternate days for 2 weeks. Androgen concentration in GnRH* plus GnRHA-treated animals decreased in the testis by about 50% with the 10X dose whereas the increase obtained in GnRH*-treated PDX group was completely abolished with the 1X dose. Histological sections were evaluated with respect of the mitotic index (MI) of the primary spermatogonia. Both GnRHA-treated intact and PDX frogs showed a dose-dependent MI decrease which reached 59% and 57% of control, respectively. In vitro incubations were carried out on testis halves at 15 C for 0, 2, 4, 6, and 8 h with the addition of 1 microgram GnRH* and 1 microgram GnRH* plus 1 or 10 micrograms GnRHA. The stimulatory effect of GnRH* and the inhibitory effect of GnRHA were apparent within 2 h. The basal mitogenic activity was affected by antagonist treatment and the inhibitory effect on the MI was evident within 2-4 h in the 10X-treated groups or within 6-8 h in the 1X treated groups. Since GnRH* and GnRHA bind to the same receptor these data strongly indicate that the effects of putative GnRH-like materials in the frog, Rana esculenta, are mediated throughout stereospecific recognition sites in both pituitary and testis.

  • Fat body involvement in vitellogenin fate in the green frog, Rana esculenta.

    Publication Date: 01/01/1988 on Comparative biochemistry and physiology. A, Comparative physiology
    by Varriale B, Di Matteo L, Minucci S, Pierantoni R, Chieffi G

    1. Since, in Rana esculenta, fat bodies contain vitellogenin, the present study was performed in order to determine whether or not fat bodies are involved in the fate of vitellogenin. 2. The experiment of November shows that fat body excision provokes plasma vitellogenin increase even in animals treated with estradion-17 beta + pituitary crude homogenate (as compared with relative control). The same picture has been shown in the April experiment. 3. The result on protein-bound phosphate in ovaries from the April experiment has shown that fat body extirpation causes a decrease of protein-bound phosphate in the ovary. 4. This results indicates that fat bodies play an important role in sequestrating circulating vitellogenin by the ovary.

  • Annual testicular activity in the gray partridge (Perdix perdix L.).

    Publication Date: 01/10/1987 on General and comparative endocrinology
    by Fraissinet M, Varriale B, Pierantoni R, Caliendo MF, Di Matteo L, Bottoni L, Milone M

    Seasonal changes in plasma androgens, testicular total protein content, gonosomatic index, and spermatogenic activity were studied in the grey partridge, Perdix perdix. Moreover, testicular androgen output after stimulation with ovine LH (oLH) was tested in vitro during different periods of the sexual cycle. Androgens and the gonosomatic index peaked in April, during which all the spermatogenic stages were observed. Total protein content in the testes was highest in January and March. Gonadal responsiveness to oLH was found to increase in the period April-May in coincidence with the hormone peak in the plasma, while February testes were irresponsive.

  • Seasonal plasma and intraovarian sex steroid profiles, and influence of temperature on gonadotropin stimulation of in vitro estradiol-17 beta and progesterone production, in Rana esculenta (Amphibia: Anura).

    Publication Date: 01/08/1987 on General and comparative endocrinology
    by Pierantoni R, Varriale B, Fasano S, Minucci S, Di Matteo L, Chieffi G

    Seasonal plasma and intraovarian estradiol-17 beta (E) and progesterone (P) fluctuations were studied by specific radioimmunoassay in the frog, Rana esculenta. Moreover, incubations of ovine-luteinizing hormone (oLH)-stimulated ovarian pieces at two different temperatures (15 and 24 degrees) have been carried out in order to evaluate the dependence of E and P output on this exogenous factor. Estradiol showed similar changes in plasma and ovaries, while P profile was better evidenced in the gonads since this hormone fluctuated in plasma, giving pulses of difficult interpretation. A shift from E to P production by the ovary near the ovulatory period (February-March) was noted. In vitro experiments were carried out using approximately equal-sized ovarian fragments containing follicles ranging from 0.7 to 1 mm and classified as early vitellogenic. High temperature induced oLH-stimulated P production within 6 h, while E increased after 24 h concomitantly with a P decline. At 15 degrees the stimulatory effect of oLH was achieved only on E output in the incubation medium after 24 h. In conclusion, our results in the frog, R. esculenta, show that E and P intervene at peak values separately during the annual cycle and that the temperature has an important role in the regulation of the steroid hormone-releasing activity.

  • Regulation of androgen production by frog (Rana esculenta) testis: an in vitro study on the effects exerted by estradiol, 5 alpha-dihydrotestosterone, testosterone, melatonin, and serotonin.

    Publication Date: 01/12/1986 on General and comparative endocrinology
    by Pierantoni R, Varriale B, Minucci S, Di Matteo L, Fasano S, D'Antonio M, Chieffi G

    The possible role of estradiol-17 beta (E2), testosterone (T), 5 alpha-dihydrotestosterone (DHT), melatonin, and serotonin on the regulation of androgen (A) production by the frog, Rana esculenta, testes was studied in vitro. E2 (10(-6) M) inhibited A production whether alone or in combination with oLH (20 micrograms) after 6 hr incubation. After 24 hr incubation. A production was reduced by E2 concentration of around 10(-6) and 10(-9) M. Melatonin and serotonin did not induce any change whichever experimental condition was used. Preincubation for 6 hr with 10(-6) M T or DHT enhanced the oLH-stimulated A production after 18 hr incubation. These data suggest that steroids may regulate their intratesticular levels without passing into the blood stream.

  • Plasma and testicular estradiol and plasma androgen profile in the male frog Rana esculenta during the annual cycle.

    Publication Date: 01/12/1986 on General and comparative endocrinology
    by Varriale B, Pierantoni R, Di Matteo L, Minucci S, Fasano S, D'Antonio M, Chieffi G

    Seasonal plasma and testicular estradiol levels were measured in the male frogs, Rana esculenta, by radioimmunoassay. In plasma samples a simultaneous measurement of androgens was carried out in order to investigate a possible relationship between androgens and estradiol-17 beta. Concomitantly with the estradiol-17 beta peak in plasma and testes during the April-May period, plasma androgens sharply decreased.

  • In vivo and in vitro stimulatory effect of a gonadotropin-releasing hormone analog (HOE 766) on spermatogonial multiplication in the frog, Rana esculenta.

    Publication Date: 01/08/1986 on Endocrinology
    by Minucci S, Di Matteo L, Pierantoni R, Varriale B, Rastogi RK, Chieffi G
    DOI: 10.1210/endo-119-2-731

    The effects of a GnRH analog (GnRHA), D-Ser-t-Bu6,desGly-NH2(10) (HOE 766) on spermatogenesis were analyzed in the frog, Rana esculenta. Intact animals caught at two different periods of the year (January and March) were treated with HOE 766 (GnRHA, 45 ng/g BW) at low (4 +/- 1 C) and high (22 +/- 2 C) temperatures. Hypophysectomized frogs were used also and, in addition to GnRHA, these animals were treated with crude pars distalis homogenate. In vitro incubations were carried out at 15 C, for 0, 6, and 24 h with the addition of 1 microgram GnRHA. Half of each testis was used as the untreated control. Histological sections of the testes were analyzed for the evaluation of the mitotic index of the primary spermatogonia. Intact March animals had mitotic indices higher than January animals. GnRHA treatment elicited an increase of the mitotic index in both intact and hypophysectomized animals. High temperature potentiated the GnRHA effect while low temperature favored pars distalis treatment. In conclusion, the present results are consistent with the fact that in the frog, R. esculenta, the magnitude of spermatogonial proliferation is temperature dependent, and for the first time it is shown that GnRH-like substances have direct stimulatory effect on the mitotic activity of the primary spermatogonia in a vertebrate.