Just ordered some Carbolin 19 for the cyclic amp boosting properties. Have been doing some searching on forskolin over the weekend and ran across some abstracts that if am reading them correctly, state forskolin raises cortisol. I am really looking for something that raises cyclic amp and Carbolin 19 seems like the perfect thing but the cortisol things made me nervous.
Dissertation zur Erlangung des Doktortitels, angenommen von: Georg-August-Universit?t G?ttingen, Mathematisch-naturwissenschaftliche Fakult?ten, 2004-04-27
Abstract (ENG)
Adrenal steroid hormones (e.g., cortisol) play a pivotal role in the regulation and maintenance of metabolic homeostasis. The secretion of glucocorticoids from adrenocortical cells into the blood is poorly understood. It has long been postulated that this occurs via simple diffusion, based on the lipophilic structure of steroid hormones. Previously, it has been demonstrated that cortisol release from and uptake of radiolabeled PAH into bovine adrenocortical cells showed physiological characteristics similar to the renal/organic anion exchanger OAT1. In this study we investigated whether an organic anion transporter (OAT) may play a role in cortisol release from the human adrenal cell line, NCI-H295R. Basal 24 h cortisol secretion increased up to threefold by pretreatment with ACTH, and up to thirtyfold with forskolin. Incubation for 24 h with PAH partially inhibited cortisol release, while cimetidine inhibition was relatively pronounced, indicating some differences between NCI-H295R cells and bovine adrenal cells. RT-PCR did not reveal an expression of human OAT1 and OAT2, but OAT3 and OAT4 mRNA was detected in NCI-H295R cells as well as in normal human adrenal tissue. The studies with HEK-293 cells stably transfected with human OAT1, OAT3, and OAT4 showed a low interaction of cortisol with hOAT1 and hOAT4 as compared to hOAT3. When human OAT1, OAT3, and OAT4 were expressed in Xenopus laevis oocytes, only hOAT3 showed radiolabeled cortisol uptake beyond non-expressing control oocytes. Cortisol uptake was saturable with an apparent Kt value of 2.4 ?M, and radiolabeled estrone sulfate uptake was inhibited by unlabeled cortisol with an IC50 of 15.6 ?M. The experiments in NCI-H295R cells showed a saturable radiolabeled estrone sulfate uptake, a potent substrate of hOAT3, with a Ki value of 9.8 ?M. The inhibition with unlabeled DHEAS and cortisol resulted in IC50 values of 10.6 and 38.9 ?M, respectively. The radiolabeled estrone sulfate uptake in NCI-H295R cells was decreased by potent inhibitors of hOAT3, i.e. probenecid, cimetidine, and glutarate. In NCI-H295R cells, radiolabeled estrone sulfate uptake was trans-stimulated by preloading with glutarate or cortisol. Likewise, radiolabeled PAH uptake was trans-stimulated by preloading the cells with PAH, glutarate, or cortisol. The 24 h forskolin treatment significantly increased radiolabeled estrone sulfate and PAH uptake in NCI-H295R cells. Semi-quantitative RT-PCR showed an increased hOAT3 mRNA expression after pretreatment with forskolin. Forskolin-treatment induced a significant increase in the enzymes of steroids biosynthesis, i.e. StAR, CYP17, 3?HSD, and CYP21A2. Immunolocalization studies for hOAT3 resulted in expression of hOAT3 in NCI-H295R cells. There was a high increase in OAT3 expression by a 24 h treatment with forskolin. Our data suggests that OAT3 is functionally expressed in NCI-H295R cells and is able to perform cortisol/anion exchange. Thereby, OAT3 may - among other release mechanisms - contribute to cortisol efflux from human adrenal cells.
J Endocrinol. 2004; 181(2):355-65 (ISSN: 0022-0795)Kelly SN; McKenna TJ; Young LS
Department of Surgery, Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Ireland
The capacity of the adrenal to produce cortisol is controlled in part by 21-hydroxylase (CYP21) and the production of androgens by 17-hydroxylase/17-20-lyase (CYP17), in response to secretagogues including ACTH, angiotensin-II (A-II) and insulin. In this study we examined the capacity of human adrenocortical cells to produce cortisol and androgens in response to these secretagogues and their ability to regulate the expression of CYP21 and CYP17. In H-295 cells, forskolin and A-II were found to stimulate production of cortisol relative to androstenedione and a similar pattern of steroid production was noted in primary human adrenocortical cells. Both mRNA and protein expression of CYP21 was upregulated with forskolin and A-II alone and in combination, as detected by Northern and Western blotting. Whereas expression of CYP17 mRNA and protein was up regulated in the presence of forskolin and forskolin in combination with insulin. The ability of steroidogenic factor-1 (SF-1) and nur77 to regulate transcription of these enzymes was examined. Forskolin, A-II and insulin increased the protein expression of SF-1. Increased binding of SF-1 to its response element in the presence of forskolin, A-II and insulin was observed. Nur77 was expressed primarily in the zona glomerulosa and fasciculata. Increased protein expression of nur77 and the greatest binding of nur77 to its response element was seen when cells were stimulated with A-II in combination with forskolin. These data indicate that nur77 may preferentially regulate steroid enzyme genes relevant to cortisol production and thereby regulate differential cortisol and adrenal androgen production.
Let me know what you guys think, thanks in advance.