Suppression of experimental autoimmune tubulointerstitial nephritis in BALB/c mice by berberine.

Berberine (BB) is a protoberberine alkaloid derived from various representatives of the Berberidaceae family. Although used as a therapeutic agent, it has not been applied in the treatment of immune-mediated disorders. In the present study, BB was administered at a daily dose of 10 mg/kg for 3 consecutive days before the induction of tubulointerstitial nephritis (TIN) by injection of bovine tubular basement membrane (TBM) antigen in BALB/c mice. The animals were investigated 2 months after TBM inoculation. The intensity of pathological injuries in animals with TIN+BB decreased significantly, an effect that correlated with the improvement of renal function. Flow cytometric analysis of peripheral blood cells showed that BB caused a decrease in the number of CD3(+), CD4(+), CD8(+), and sIg(+) lymphocytes in comparison with TIN mice. The same tendency was noticed in the lymphocytes from kidney infiltrates of treated animals. The control animals treated only with BB showed a decrease in the number of CD3(+), CD4(+), CD8(+) T-lymphocytes in comparison with control nontreated mice. Our results, thus, indicate that BB has an immunosuppressive effect in the TIN model, which is an analogue of various human kidney autoimmune diseases.

Leukaemia inhibitory factor stimulates proliferation of prospermatogonial stem cells.

The effect of leukaemia inhibitory factor (LIF) on the proliferation of prospermatogonial stem cells was tested in vitro. Pieces of 3-day-old rat testis were cultured in the presence of a range of doses of LIF alone or in combination with 1 ng mL(-1) seminiferous growth factor (SGF). Stimulation of the proliferative activity of quiescent prospermatogonia was detected immunocytochemically with a cell proliferation kit. After 24 h culture, LIF significantly increased the percentage of labelled prospermatogonia, with the peak of activity at 20 pg mL(-1). The combination of LIF and SGF resulted in a decrease in DNA synthetic activity of the germ cells. Hence, LIF and SGF play a role in local regulation at the onset of spermatogenesis in the rat testis.

Differential effects of prepubertal rat Sertoli cell secreted proteins on somatic testicular and nontesticular cells.

There is little information on the mitogenic and immunoregulatory activities of proteins, secreted by prepubertal Sertoli cells during the stage of meiosis initiation and before creation of the blood-testis barrier. We have previously demonstrated dose-dependent and age-related stimulation of BALB/c 3T3 fibroblasts and quiescent rat prespermatogonia (Kancheva et al., 1990) as well as inhibition of natural killer cell activity of mice, guinea pigs and human lymphocytes (Nikolova et al., 1992) by Sertoli cell-conditioned medium derived from 12-day-old rats. In the current study, using splenic lymphocytes stimulated by PHA, LPS and Con A, we have shown a dose-dependent inhibition of T and B lymphocyte proliferation by prepubertal Sertoli cell-secreted proteins (pSCSP). These results suggest that by the time the blood-testis barrier had been formed, Sertoli cell in rat testis had already synthesized immunoregulatory proteins. In addition we have found that pSCSP stimulate the proliferation of TM3 Leydig but not TM4 Sertoli cells. The differential effect of pSCSP is an expression of the different balance between growth factors secreted by Sertoli cells, which in turn is dependent on the requirements of the cell types at each stage of testicular development.

Species-specific effect of proteins secreted by cultured pre-pubertal rat Sertoli cells on natural killer cell activity.

The effect of proteins secreted by cultured pre-pubertal rat Sertoli cells (pSCP) on natural killer (NK) cell activity of rat, mice and guinea pig splenocytes and human peripheral blood lymphocytes was estimated. The results indicate that pSCP inhibited, in a dose-dependent manner, NK cell activity of mice, guinea pig and human lymphocytes but did not suppress lysis of YAC-1 target cells by rat NK cells. Species-specific differences in the effect of pSCP on NK cell activity probably result from differences in the binding of proteins within the effector cells. These data indicate that in the pre-pubertal period of gonadal development immature Sertoli cells synthesize a factor/s which might contribute to the maintenance of specific testis immunological environment.

Ultrastructural alterations in mouse spermatogenic cells after treatment with anticancer drug biocarbazine.

Single doses of anticancer drug biocarbazine (BC)--DTIC synonym--were injected intraperitoneally at 50 and 200 mg/kg body weight to sexually mature BALB/c mice. Among other features previously reported (Martinova et al. 1989) BC causes ultrastructural alterations in spermatogonia and spermatocytes significantly expressed after administration of higher dose. In addition BC induces some defects in acrosome formation of early spermatids in Golgi and cap phase, while spermatids in later stages of maturation showed marked resistance to BC treatment.

Early effect of the anticancer drug biocarbazin (DTIC synonym) on mice spermatogenesis.

Biocarbazin (DTIC synonym) is an anticancer drug acting as a purine analogue, as an alkylating agent, as a SH-group blocker. Biocarbazin administration in doses 50 and 200 mg/kg of body weight to adult male BALB/c mice suppresses the process of spermatogenesis. Seminiferous tubule of the testis displayed dose-dependent histological alterations manifested with decrease of mitotically dividing cells and increase in the number of multinucleated spermatocytes and spermatids. RNA synthetic activity studied by means of autoradiography showed a tendency for a reduction in the spermatogonia and pachytene spermatocytes.