Common usage of nonsteroidal anti-inflammatory drugs (NSAID) has led to many longterm
and potentially harmful effects for organisms, including human. Many of these effects
remain unclarified, although some researches have already confirmed that some drugs,
including NDAID, act as endocrine disruptors. The findings of in vitro and in vivo studies
so far show, that NSAID are able to modulate estrogen receptor (ER), progesterone receptor
(PR) and the peroxisome proliferator activated receptor gamma (PPARγ). Effects of NSAID
on other receptors, e. g. androgen receptor (AR) and glucocorticoid receptor (GR) are less
studied. With this purpose, we studied in our thesis the effects of selected NSAID on these
two receptors. Along with two typical NSAID representatives, diclofenac (DIC) and its
metabolite 4-hydroxydiclofenac (4-HD), we also chose paracetamol (PAR) and natural
representative with anti-inflammatory effect, piceatannol (PIC). They all have antiinflammatory
effect in common, although it is broadly known as a characteristic of NSAID.
Most representatives of group of NSAID inhibit two isoforms of cyclooxygenase (COX),
COX-1 and COX-2. Diclofenac in lesser extent also inhibits COX-3. They attribute this
inhibition also to PAR.
As a model system for determination their effects we used the cell line MDA-kb2, which
expresses functional androgen and glucocorticoid receptor with the ability to differ agonistic
and antagonistic properties of the selected substance. First, we used cytotoxicity test to
confirm that selected substances in firstly chosen concentrations show cell survival rate more
than 80 %. For DIC, PAR and PIC first non-cytotoxic concentration was 175 μM and for 4-
HD it was 250 μM. The first non-cytotoxic concentrations and lower concentrations were
used later on with in vitro assay. This was screening luciferase assay based on the activation
of transcription of the gene for luciferase. Activation of transcription or level of luciferase
activity was used as indicator of the effect of tested substances on AR or GR. The test results
showed that all test substances have significant agonistic effect on AR and GR at certain
concentrations. Agents DIC and PAR work as agonists of AR at concentrations 175, 100,
10, 1 and 0.1 μM, substance 4-HD at concentrations 250, 100, 10, 1 and 0.001 μM, substance
PIC at 175, 100 and 1 μM. Agonistic effect on GR of DIC and PAR was showed at
concentration175 μM, substance 4-HD showed this at 250, 100 and 10 μM, PIC at 175, 100
and 10 μM. All tested substances, except PIC, works also as antagonist of AR, namely DIC
at concentrations 175, 10, 1 and 0.01 μM, 4-HD at 250, 100, 10, 1 and 0001 μM, PAR at 10,1, 0.01 and 0.001 μM. Weak anti-glucocorticoid effect was evidenced only for substances
DIC at concentrations 175 and 100 μM, along with its metabolite 4-HD at concentrations
250 and 100 μM.
On the basis of our experimental results, we can claim that selected substances modulate AR
and GR. We must not neglect the fact that tested substances are able to modulate AR and
GR at therapeutic concentrations and also at lower concentrations, which were also found in
water sources in the environment. Definitely more detailed in vitro and in vivo studies are
needed to evaluate exact mechanisms of action and potentially harmful effects of the selected
substances on androgen and glucocorticoid system.
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