Talk:CYP1A2

message: the second paragraph (reproduced below in case its location changes) is unclear in its meaning.
Expression of CYP1A2 appears to be induced by various dietary constituents.[3] Vegetables such as cabbages, cauliflower and broccoli are known to increase levels of CYP1A2,lower levels of CYP1A2 in South Asians appears to be due to cooking these vegetables in curries using ingredients such as cumin and tumeric, ingredients known to inhibit the enzyme.[4]
the statement that cruciferous vegetables cause higher levels of CYP1A2 doesn't seem to make sense in combination with the statement following, that south asian curries made with cumin and turmeric lower levels of CYP1A2. i don't have the expertise to determine which of the following is the case, but someone who does should re-write this part to be clearer.
possible meanings:
1) cruciferous vegetables increase CYP1A2 levels, and curry spices reduce levels. (if so, then the statements should just be separated)
2) cruciferous vegetables increase CYP1A2 levels, but in combination with curry spices they instead reduce levels. (if so, this should be made clearer)
additionally, the status of south asians intended to be conveyed is unclear. is it the case that south asians, due to curry spices, have reduced levels despite eating cruciferous vegetables? is it the case that south asians have reduced levels due to the combination of spices and vegetables? et cetera.
hopefully this can be easily cleared up by someone with an understanding of the enzyme. sorry for the long commentary, but the many ways this section can be read seemed to require an explanation of the problem (and why i can't fix it).
(Eristikophiles (talk) 05:15, 1 March 2012 (UTC)
replies: text: I certainly agree with Eristikophiles!  The subject is difficult for many of us, and the very unclear prose makes it worse.  Someone, please copyedit.  --Hordaland (talk) 08:25, 9 March 2014 (UTC)
replies: text:   Confusion can be traced back to the source where the term "lower levels" was incorrectly used when what should have been used is "lower activity".  Cruciferous vegetables contain chemical that induce the expression of CYP1A2 (through activation of AHR and PXR) resulting in higher levels of the enzyme.  Cumin and turmeric directly inhibit the activity of the enzyme, not reduce its levels. Please note that the source also states that "cumin and turmeric [are] ingredients known to inhibit the enzyme". I have eliminated the confusion by replacing "lower levels" with "lower activity".  The South Asian diet is high in both spices and cruciferous vegetables.  However the direct inhibition of CYP1A2 by the spices apparently more than compensates for the increased levels of CYP1A2 caused by the vegetables. We also need a better source.  and/or  may qualify but both are behind a paywall so that I cannot verify they directly say that the spices inhibits the enzyme. Boghog (talk) 12:22, 9 March 2014 (UTC)
thread_title:  second paragraph unclear 

message: Whether verapamil is a potent CYP1A2 inhibitor or a weak CYP12A inhibitor? I am confused. --It's gonna be awesome!✎Talk♬
'Oral Contraceptives' in the moderate inhibitors list here could use a bit of specificity. Which oral contraceptives and what's doing the inhibiting? The cited source doesn't clarify, perhaps someone has another source with specific information? QuantumCatgirl (talk) 13:03, 14 April 2021 (UTC)
thread_title:  [[CYP1A2#Ligands]]