Effects of Costus speciosus ethanolic extract on male rats: The action mechanism and the ability to impregnate.

To examine the action mechanism that mediates the anti-fertility effect of Costus speciosus extract, research was conducted on male Sprague-Dawley rats. Costus extract was given to male rats for 14 days at various doses, namely 275, 550 and 1,100 mg kg-1 day-1 in 0.5% sodium CMC. The results showed that Costus extract with doses ranging from 275 to 1,100 mg kg-1 day-1 was able to inhibit pregnancy among female rats by 10-70%. No obstacles in terms of sexual behavior were identified among male rats. The anti-fertility effect of Costus extract kicked in without involving a decreased level of male reproductive hormones.

Immunomodulatory Effects of Ethanolic Extract of Thyphonium flagelliforme (Lodd) Blume in Rats Induced by Cyclophosphamide.

The present study aimed to examine the immunomodulatory effect of ethanolic extract of Typhonium flagelliforme (Lodd) Blume in cyclophosphamide-treated rats. The immunomodulatory effects were determined by lymphocytes proliferation, phagocytic activity of macrophages, plasma cytokines of tumor necrosis factor-α, interleukin-1α, interleukin-10 levels, and killer T cells (CD8+ T cells) counts. The results showed that the administration of ethanolic extract of T flagelliforme reduced immunosupessive effect on lymphocyte proliferation, increase the number and phagocytic activity of macrophages in cyclophosphamide-treated rats. Moreover, the ethanolic extract of T flagelliforme also significantly (P < .05) improved the immune system activities especially the proliferation of CD8+T cells and reduced the suppressive effects on cytokines such as tumor necrosis factor-α and interleukin-1α. In conclusion, the ethanolic extract of T flagelliforme has immunomodulatory properties in cyclophosphamide-treated rats. The results suggest that T flagelliforme can reduce immunosuppresive effect caused by a chemotherapeutic agent.

Gonadotropin-inhibitory hormone is a hypothalamic peptide that provides a molecular switch between reproduction and feeding.

OBJECTIVE: Gonadotropin-inhibitory hormone (GnIH)-3 is a neuropeptide that plays a major role in the regulation of reproduction and feeding in mammals. MATERIALS AND METHODS: We measured endocrine and behavioural parameters of reproduction in sheep, and sexual behaviour in sheep, mice and cynomolgus monkeys. In addition, GnIH gene expression (in situ hybridization) was examined in ewes, and effects of GnIH-3 on food intake and energy expenditure were measured in various species. GnIH-3 was infused (i.v.) into ewes after an i.m. injection of estradiol benzoate to determine whether the peptide blocks the surge in luteinizing hormone (LH) secretion. RESULTS: GnIH gene expression was reduced in the preovulatory period in ewes. Infusion (i.v.) of GnIH-3 blocked the estrogen-induced LH surge (in ewes). Intracerebroventricular infusion had no effect on female or male sexual behaviour in each of the three species, but increased food intake. There were no effects on energy expenditure in sheep or rats. GnIH increased fos protein (immunohistochemistry) was seen in orexigenic neurons (in sheep and rats), but also in anorexigenic neurons (in sheep). CONCLUSIONS: GnIH-3 reduces reproductive hormone levels and increases food intake in mammals without reducing energy expenditure. There is minimal effect on reproductive behaviour. The dual effect on reproduction and feeding suggests that GnIH-3 provides a molecular switch between these two functions. Blockade of the positive feedback effect of estrogen with parenteral infusion indicates that this peptide may have utility as a blocker of reproductive function in mammals.