Finasteride and neurodegenerative diseases

[abcdefg]

Could propecia cause brain diseases? I thought finasteride only inhibits 5ar type 2 which is not found in the brain only the prostate and liver right?
http://www.pahealthsystems.com/message35630.html
This article seems to suggest that finasteride could cause diseases like alzheimers.

 

[Rage]

I think you missed the important paragraph:

"Dutasteride inhibits both type I and
type II 5AR achieving a reduction of up to 94% of DHT. Type I is the
only 5AR expressed in the brain. Its long term inhibition was never
studied when dutasteride was approved by the FDA. Blocking DHT
synthesis in the brain like this also blocks allopregnanolone production
there. "

 

[abcdefg]

No I actually saw that. So none of that applies to propecia then? So dutasteride people should be scared of this?

 

[Lorenzo_91]

Negative. None should be scared.

 

[Jm0311]

we can go on and on and on....and google new sh*t to say finasteride does

 

[michael barry]

we have a biological precedent of men who dont have the five alpha reductase type 2 enzyme genetically, and they live long healthy lives.


the type two enzyme is only located in hair follicles (the innermost portion of the outer root sheat) and in the prostate. Thats it.



The type one enzyme is located in more sensitive areas, and it may have a purpose in the body that is important, we dont know yet. Its in the adrenal, kidney, liver chest skin, back skin, brain, sebocytes, sebaceous glands.

 

[Felk]

I think it's more about what happens when finasteride effects other hormones that are found in the brain, and are part of the brain's function, like inhibiting dihydroprogesterone.

 

[powersam]

but once again we can refer back to the pseudohermaphrodites who had no mental issues.

on the dutasteride side, are there not people born with total androgen insensitivity?

either way at the dose i'm on, it reduces type 1ar by around 15% or so, which i assume would be well within the natural variation range for the enzyme anyway.

 

[Felk]

but once again we can refer back to the pseudohermaphrodites who had no mental issues.

But is this for certain? I know none were recorded, but that doesn't necessarily mean much. A large proportion of mental health problems go undiagnosed. I wonder if I can turn up the data Bryan used to post about them, and see the level of detail in which they were studied.

Though blocking the 5ar2 enzyme after puberty is certainly different than being born without it, knowing that the pseudos had no mental issues would make me feel better

 

[Jacobo]

Also, Bryan posted before that he read some study saying that men castrated before 40 years old (he remebered that age) do not develop prostate cancer, it would be interesting to know if they develop more or less or the same mental issues than the rest of the population. Castrated men are not born with the condition, obviously.

 

[Apoc]

Wouldn't women like... drop dead if this was true since they have almost no DHT?

 

[Pondle]

Good point. I read somewhere that in adults, basal T and DHT are 5–50 times higher in men than in women. So given that most women lead relatively healthy lives, and live longer than men, on average, I'd think there should be no worries at all.

 

[Knendell]

but once again we can refer back to the pseudohermaphrodites who had no mental issues.

But is this for certain? I know none were recorded, but that doesn't necessarily mean much. A large proportion of mental health problems go undiagnosed. I wonder if I can turn up the data Bryan used to post about them, and see the level of detail in which they were studied.

Though blocking the 5ar2 enzyme after puberty is certainly different than being born without it, knowing that the pseudos had no mental issues would make me feel better

Very good point. Easrly in developement the brain can adapt and other portions of the brain can compensate for some things. I once read a story of a little girl who had half of her brain removed because of seizures and the other half took on 90 something percent of what the other half did.

 

[docj077]

I think it's more about what happens when finasteride effects other hormones that are found in the brain, and are part of the brain's function, like inhibiting dihydroprogesterone.

I agree with this poster's observation.

Inhibition of dihydroprogestone production is the biggest problem with 5AR inhibitors. If you inhibit production of the above hormone, then you inhibit the production of some neuroactive steroids.

Some one needs to look it up (because I don't have the time), but one of the isotypes of 5AR should control the 5-alpha progesterone reaction more than the other and thus metabolize more progesterone than the other.

It's important to note that by inhibiting 5AR function, one not only decreases DHT production, but also increases progesterone levels. Progesterone is a far more potent 5AR inhibitor than propecia.

Something else interesting to note is that those with seizure disorders should actually not take 5AR inhibitors. By decreasing the production of neuroactive steroids like allopregnanolone, which is a GABA receptor modulating neurosteroid, you actually increase the risk of seizure activity. That's something that you won't find in your PDR.

 

[abcdefg]

So you think its not a good choice for a young man to take propecia for prevention of male pattern baldness? those are some pretty risky effects.

 

[Pondle]

My understanding was that Propecia had no effect on neurosteroids, as finasteride only blocks 5AR2 which is not found in the brain. As for the significance of 5AR1, personally I'm not bothered. I read somewhere that women have 3 and 3.5 times less 5AR type I and II, respectively, than men, so I figure we can afford safely to block 50% of 5ARI with dutasteride.

 

[docj077]

My understanding was that Propecia had no effect on neurosteroids, as finasteride only blocks 5AR2 which is not found in the brain. As for the significance of 5AR1, personally I'm not bothered. I read somewhere that women have 3 and 3.5 times less 5AR type I and II, respectively, than men, so I figure we can afford safely to block 50% of 5ARI with dutasteride.

I agree with this post. This seems like a reasonable observation.

 

[Whyatt]

Then why do some women lose hair while on anti-pregnancy products based on progesterone?

 

[spinner2]

Any major hormonal changes can shock your system into a Telogen Effluvium shed.

 

[Whyatt]

Even after product has been removed? :roll: