Health Research (thyroid hormone focus)

http://www.endocrine-abstracts.org/ea/0008/default.htm

a bit overwhelming for me. but maybe someone else may find it useful

examples
http://www.endocrine-abstracts.org/ea/0008/ea0008p84.htm
(click on [P84])
shows study wheich verfies the validity of home cortsiol tests , including saliva..provided of course they are correctly collected and a highly sensitive cortisol assay i accurately done.

PHYTOESTROGENS INHIBIT mRNA EXPRESSION AND ACTIVITY OF AROMATASE IN HUMAN GRANULOSA-LUTEAL (GL) CELLS

S Rice & SA Whitehead

Basic Medical Sciences, St George's Hospital Medical School, London SW17 0RE, UK.

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Phytoestrogens bind weakly to oestrogen receptors and can initiate oestrogen-dependent transcription. They are promoted as natural alternatives to HRT and yet epidemiological evidence suggests that they may protect against breast and prostate cancer. Studies in cell-free preparations have shown that phytoestrogens can inhibit the activity of aromatase and that the inhibition is, at least partly, competitive with androgen substrates. The question as to whether chronic exposure to phytoestrogens may alter the expression of aromatase and thereby modulate the conversion of androgens to oestrogens has not been addressed.

We have investigated the effects of three isoflavones, genistein, diadzein and biochanin A, two flavones, quercetin and apigenin and the mycotoxin zearalenone on mRNA and protein expression of aromatase after exposure of human GL cells to these phytoestrogens for 48 h. Real time RT-PCR was used to quantitate aromatase mRNA levels and normalized against two house-keeping genes beta-actin and GAPDH. The cellular concentration of aromatase was quantified with Western blots that were sequentially exposed to antibodies against aromatase and beta-actin. For all experiments the conversion of testosterone to oestradiol over a 4h period, prior to using cells for mRNA or protein expression, was measured. Thus biological activity was assessed in the same cells as either mRNA/protein expression was measured.

Our preliminary results show that relatively high concentrations of phytoestrogens (10 micromolar) inhibit the expression of aromatase and that this is reflected in a reduced ability of GL cells to convert testosterone to oestradiol. Lower doses of phytoestrogens were ineffective in this respect. This is the first study to identify inhibitory effects of phytoestrogens on the mRNA and protein expression of aromatase in primary cultures of human cells. This may be of significance in the epidemiological evidence that diets high in phytoestrogens may protect against breast cancer.

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I wonder if this reduces overakl oestradiol in females?
I also wonder if aromatase inibition would led to more DHT being produced and hair loss?

Reversible Subclinical Hypothyroidism in the Presence of Adrenal Insufficiency
Three case studies offer insights into the complexities of thyroadrenal interactions.
Endocr Pract 12(5) 2006

"In patients with both hypothyroidism and adrenal insufficiency, adrenal crisis can be precipitated if thyroid hormone replacement is instituted before the initiation of corticosteroid therapy.[1]"

"In this report, we describe 3 young patients in whom mild hypothyroidism was detected but who, in fact, had severe adrenal insufficiency. More interestingly, the thyroid state normalized solely by treatment of the adrenal insufficiency"

" Clinical signs and symptoms of adrenal insufficiency could be subtle, and the discovery of TSH elevation might deflect the caregiver from attending to the true diagnosis. Hence, physicians should contemplate the hypothalamicpituitary-adrenal axis in patients with mild hypothyroidism or compensated hypothyroidism, regardless of evidence of autoimmunity. It could be inferred that physiologic levels of glucocorticoids and mineralocorticoids are essential "

1. Schatz DA, Winter WE. Autoimmune polyglandular syndrome. II: Clinical syndrome and treatment. Endocrinol Metab Clin North Am. 2002;31:339-352.