Estrogenic control of monoamine oxidase A activity in human neuroblastoma cells expressing physiological concentrations of estrogen receptor

Assaying Estrogenicity by Quantitating the Expression Levels of Endogenous Estrogen-Regulated Genes

“…In vivo assays have been conducted because there seems to be a correlation between mood changes and estradiol levels that may be mediated through the activity of monoamine oxidases (51)(52)(53). The activity and expression of MAO-A is inversely correlated both in vivo and in vitro to the estradiol concentration (49,50), which is similar to the regulation we have observed in MCF-7 cells. However, MAO genes may be induced by E2 in some tissues; Sarabia and Liehr (54) showed that expression of the MAO-B gene actually is induced by E2 in hamster kidneys.…”

“…The expression level of pS2 mRNA is a widely used indicator of estrogenicity, and the translation product of pS2 mRNA is also induced in MCF-7 cells in response to estrogen (37). The 9 kDa encoded pS2 protein belongs to the trefoil family of peptides (48)(49)(50). In vivo assays have been conducted because there seems to be a correlation between mood changes and estradiol levels that may be mediated through the activity of monoamine oxidases (51)(52)(53).…”

“…However, the required concentrations are so high that the effects may not be ER mediated; this is similar to what has been observed in SK-N-BE/SK-ER3 cells, in which the observed effects of tamoxifen apparently are independent of the presence of ERa. Unfortunately, the possible expression of ER,I has not been investigated in the SK-N-BE cells, although the lack of E2 response indicates that neither receptor subtype is present (48,49).…”

Interaction between estrogens and antidepressants in the forced swimming test in rats

“…Thus, clinical reports indicate that long-lasting steroid treatment, yielding high levels of estrogens, decreases imipramine's metabolism (Somani and Kurana 1973;Jensvold 1996). In addition, at least two reports point out that chronic estrogen treatment (7 days to 3 weeks) inhibits the activity of monoamine oxidase types A and B in the rat brain (Ma et al 1995;Holschneider et al 1998). However, acute treatments have been reported not to affect the activity of these enzymes (Holschneider et al 1998).…”

Reduction in the latency of action of antidepressants by 17 β-estradiol in the forced swimming test

“…Several reports indicate that chronic treatment with estrogens (Holschneider et al 1998;Ma et al 1995) or their use at very high doses (Somani and Khurana 1973) affect the metabolism of antidepressants by interacting with the monoamino-oxidase (Holschneider et al 1998;Ma et al 1995) or the cytochrome P450 system (Wang and Strobel 1997). Therefore, it could be proposed that the synergistic action of E 2 involves changes in the metabolism of antidepressants.…”