6 ms·

Marijuana exposure in utero has lifelong consequences in mice

19 points by shawndumas 11y ago

pil4rin 11y ago
Shame on Ars for this clickbait trash- with "In mice at least, although humans might want to be cautious." as a subtitle it is hard to take the rest of the article seriously. Then you find out they were injecting mice with some unspecified amount of THC within Saline solution (please correct me if there is a specified amount, but I had to dig to find this at http://www.pnas.org/content/suppl/2015/10/09/1514962112.DCSupplemental/pnas.201514962SI.pdf http://www.pnas.org/content/suppl/2015/10/09/1514962112.DCSu...) "THC (THC Pharm) was diluted in 0.9% NaCl (saline) solution containing 3% (vol/vol) DMSO and 2% (vol/vol) Tween-80 and administered intraperitoneally (i.p.) at a final dose of 3 mg/kg to pregnant females for 5 consecutive days, from E12.5 to E16.5. Control mice were injected with vehicle solution." This will be on Fox news within a week, and when it is- they will monger fear in older generations (those who typically control laws by either voting or creating bills) that are too lazy to research and come to their own conclusions.
- 6stringmerc 11y ago
  Thank you for posting context where it lacks. I've thought that site has had some, well, issues for a while. Mostly when they decided it'd be a great "scoop" to go deep into their forum archives for anything and everything Snowden had said there. While it was within their rights, and an interesting story as a concpet, the execution was so tabloid and tone-deaf to criticism I figured there weren't the type of site for me.
- ashrust 11y ago
  It looks like the paper says they were given 3mg/kg THC per day for 5 consecutive days. So it does seem the dose is specified. It's pre clinical and far from surprising but 3mg/kg is a lot of THC, the equivalent of using ~1g of strong stuff by yourself (assuming no THC is lost during consumption).
  - pil4rin 11y ago
    Yeah I found that- but they never stated dilution amounts or total fluids given to the mice on those days, unless they mentioned it elsewhere.
  - pil4rin 11y ago
    After looking up the potency of currently popular edibles, the highest dosage I could find per item was the Cheeba Chew Deca Dose(http://www.cheebachews.com/wp-content/uploads/2015/02/deca_15.pdf http://www.cheebachews.com/wp-content/uploads/2015/02/deca_1...) @ claimed 175mg of THC per piece (actual was 162.1). As far as I know, this is a heroic dose of THC of which the typical user would not frequent. In order to match the dosage within the mice, I'd have to eat just over 6 of these per days for a working week to produce the same results (obviously without comparing intake medium). I understand this was to attempt to see if there were any issues that should be researched further, but the Ars article took it at face value and claimed we should (as humans) avoid during pregnancy.
- pil4rin 11y ago
  A few of the comments on the Ars article are stating the dosage of the THC was given at 3mg/kg- but the word "dilution" along with "intraperitoneally" lets us know it was delivered via liquid injection into the gut directly. Are we sure the amount of THC injected was 3mg per kg of body weight, or was that the diluted solution (of which there was no total liquid measurement for). This decent question asked within comments: "Jesus, that dose. 3 mg/kg, An average mouse is 0.0192~ kg if the googles are right. A dose of edibles around 10mg for a 68kg~ (150lb) human will result in a pretty faded human, so that works out to... mm.. 0.147mg/kg if I did the math right. So the dose being tested here is literally 20 times higher than the average dose a human will ingest. I don't know a single person who could eat 3 pot brownies a day, let alone 20. I'd be willing to wager a lot of money on 20 pot brownies a day, every day, for any length of time would be enough to cause negative health effects! Silly question - why don't they titrate up? The amount used in this study is a massive, massive dose beyond what even a hardcore recreational user would smoke on a daily basis."-TK
  - jws 11y ago
    Biologists routinely test with larger concentrations in order to make the effect more visible. Sometimes this creates a new effect where you overwhelm a process. Sometimes it just shortens the test and saves the lives of a lot of mice. If you are a programmer, think of it as stress testing. I'm testing a concurrent memory allocator right now that I suspect sometimes corrupts itself. I'm hitting with an insane barrage of allocation and deallocation calls, way more than any recreational software user would ever do, trying to provoke it into failing. So far, no luck, but if I can get a failure I will have saved a great deal of time over testing it with normal call rates. On the other hand, if I tested it by just doing an insane number of allocations, I would provoke a failure completely unrelated to normal use (out of memory).
    - codeulike 11y ago
      provoke a failure completely unrelated to normal use and so ... why bother? (wrt biology, not your programming equivalent)
- justaman 11y ago
  A similar study was done on chimps in the late 50's. Chimps were setup with a "oxygen mask" where, instead of oxygen, marijuana smoke was present. Ultimately they reported that the marijuana smoke killed the chimps rather than asphyxiation.
Raphmedia 11y ago
"So, like alcohol, another recreational drug that is legal in the US, marijuana is likely best avoided by pregnant women." This is so refreshing to see articles made with a neutral tone about marijuana and not the usual "IT'S EVIL" talk. It's a recreational drug like any other. You wouldn't drink when pregnant, you shouldn't smoke either. Those fact shouldn't be related at all about whether the substance is legal or not.
- Shivetya 11y ago
  except you can second hand inhale it, so there is an additional concern. That same concern occurs when you have children around. How much THC is in second hand smoke, let alone carcinogens and pollutants?
  - oldmanjay 11y ago
    It's pretty intellectually difficult to extrapolate effects from heavily dosing pregnant mice into effects from microdosing pregnant humans. By which I mean your comment has no logical basis, only an emotional one. I explain this only so you understand the downvotes.
    - drzaiusapelord 11y ago
      Is it? When I was a kid second hand cigarette smoke was considered harmless. It certainly isn't today. We just don't the research because of restrictive laws banning it for the most part and the pro-pot acitvists disingenuous commentary about how "safe" it is. I feel like any politicized recreation substance will go down the path of cigarettes. Fanboys will claim its neutral, if not good for you, and then eventually the science and bias will shake out about its dangers. For example, we do know there's an increase for mental illness an decrease in IQ in kids who habitually smoke pot: https://today.duke.edu/2012/08/potiq https://today.duke.edu/2012/08/potiq Among a long-range study cohort of more than 1,000 New Zealanders, individuals who started using cannabis in adolescence and used it for years afterward showed an average decline in IQ of 8 points when their age 13 and age 38 IQ tests were compared. Quitting pot did not appear to reverse the loss either, said lead researcher Madeline Meier, a post-doctoral researcher at Duke University. The results appear online Aug. 27 in PNAS. The key variable in this is the age of onset for marijuana use and the brain's development, Meier said. Study subjects who didn't take up pot until they were adults with fully-formed brains did not show similar mental declines. --- So yes, pot can be harmless for a 21 year old, but not for a 15 year old. I'm all for legal pot, but only at age 21 or higher. I don't think the especially libertine attitudes we're seeing via web culture are helping. Its not harmless for certain age groups. We don't know enough about the brain and pot to make these types of assessments. Erring on the side of caution is the only rational path here and that includes making sure pregnant women aren't exposed to pot smoke.
meeper16 11y ago
I'd highly recommend listening to this experiment on how this truly works when considering epigentics: https://youtu.be/9DAcJSAM_BA?t=1764 https://youtu.be/9DAcJSAM_BA?t=1764
- pil4rin 11y ago
  Fantastic suggestion- I enjoyed this immensely. Thank you.
  - meeper16 11y ago
    Your welcome. The whole field of epigentics is turning everything we know about biology on its side. It's amazing.
dismal2 11y ago
I don't see why they didn't just have them consume food with oil in it, this seems like a highly unnatural delivery mechanism. Relevant comment from Ars: > Interesting to note... If you look at the study > "THC (THC Pharm) was diluted in 0.9% NaCl (saline) solution containing 3% (vol/vol) DMSO and 2% (vol/vol) Tween-80 and administered intraperitoneally (i.p.) at a final dose of 3 mg/kg to pregnant females for 5 consecutive days, from E12.5 to E16.5. Control mice were injected with vehicle solution." > DMSO is TOXIC to developing brains. Its actually recommended not to use it in studies because it causes too much damage. > "The in vitro results suggest avoiding the use of BeOH (which also is more toxic than the other solvents in the in vivo test) and DMSO and using PEG400, EtOH and DMF even though the latter induced a body weight decrease in the B6D2F1 mouse strain. " > http://www.ncbi.nlm.nih.gov/pubmed/8011014 http://www.ncbi.nlm.nih.gov/pubmed/8011014 > It would seem as though they purposefully paired the THC with a solvent that would cause the relevant brain abnormalities.

19 points by shawndumas 11y ago

Shame on Ars for this clickbait trash- with "In mice at least, although humans might want to be cautious." as a subtitle it is hard to take the rest of the article seriously. Then you find out they were injecting mice with some unspecified amount of THC within Saline solution (please correct me if there is a specified amount, but I had to dig to find this at http://www.pnas.org/content/suppl/2015/10/09/1514962112.DCSupplemental/pnas.201514962SI.pdf http://www.pnas.org/content/suppl/2015/10/09/1514962112.DCSu...) "THC (THC Pharm) was diluted in 0.9% NaCl (saline) solution containing 3% (vol/vol) DMSO and 2% (vol/vol) Tween-80 and administered intraperitoneally (i.p.) at a final dose of 3 mg/kg to pregnant females for 5 consecutive days, from E12.5 to E16.5. Control mice were injected with vehicle solution." This will be on Fox news within a week, and when it is- they will monger fear in older generations (those who typically control laws by either voting or creating bills) that are too lazy to research and come to their own conclusions.

6stringmerc 11y ago
Thank you for posting context where it lacks. I've thought that site has had some, well, issues for a while. Mostly when they decided it'd be a great "scoop" to go deep into their forum archives for anything and everything Snowden had said there. While it was within their rights, and an interesting story as a concpet, the execution was so tabloid and tone-deaf to criticism I figured there weren't the type of site for me.
ashrust 11y ago
It looks like the paper says they were given 3mg/kg THC per day for 5 consecutive days. So it does seem the dose is specified. It's pre clinical and far from surprising but 3mg/kg is a lot of THC, the equivalent of using ~1g of strong stuff by yourself (assuming no THC is lost during consumption).
- pil4rin 11y ago
  Yeah I found that- but they never stated dilution amounts or total fluids given to the mice on those days, unless they mentioned it elsewhere.
- pil4rin 11y ago
  After looking up the potency of currently popular edibles, the highest dosage I could find per item was the Cheeba Chew Deca Dose(http://www.cheebachews.com/wp-content/uploads/2015/02/deca_15.pdf http://www.cheebachews.com/wp-content/uploads/2015/02/deca_1...) @ claimed 175mg of THC per piece (actual was 162.1). As far as I know, this is a heroic dose of THC of which the typical user would not frequent. In order to match the dosage within the mice, I'd have to eat just over 6 of these per days for a working week to produce the same results (obviously without comparing intake medium). I understand this was to attempt to see if there were any issues that should be researched further, but the Ars article took it at face value and claimed we should (as humans) avoid during pregnancy.
pil4rin 11y ago
A few of the comments on the Ars article are stating the dosage of the THC was given at 3mg/kg- but the word "dilution" along with "intraperitoneally" lets us know it was delivered via liquid injection into the gut directly. Are we sure the amount of THC injected was 3mg per kg of body weight, or was that the diluted solution (of which there was no total liquid measurement for). This decent question asked within comments: "Jesus, that dose. 3 mg/kg, An average mouse is 0.0192~ kg if the googles are right. A dose of edibles around 10mg for a 68kg~ (150lb) human will result in a pretty faded human, so that works out to... mm.. 0.147mg/kg if I did the math right. So the dose being tested here is literally 20 times higher than the average dose a human will ingest. I don't know a single person who could eat 3 pot brownies a day, let alone 20. I'd be willing to wager a lot of money on 20 pot brownies a day, every day, for any length of time would be enough to cause negative health effects! Silly question - why don't they titrate up? The amount used in this study is a massive, massive dose beyond what even a hardcore recreational user would smoke on a daily basis."-TK
- jws 11y ago
  Biologists routinely test with larger concentrations in order to make the effect more visible. Sometimes this creates a new effect where you overwhelm a process. Sometimes it just shortens the test and saves the lives of a lot of mice. If you are a programmer, think of it as stress testing. I'm testing a concurrent memory allocator right now that I suspect sometimes corrupts itself. I'm hitting with an insane barrage of allocation and deallocation calls, way more than any recreational software user would ever do, trying to provoke it into failing. So far, no luck, but if I can get a failure I will have saved a great deal of time over testing it with normal call rates. On the other hand, if I tested it by just doing an insane number of allocations, I would provoke a failure completely unrelated to normal use (out of memory).
  - codeulike 11y ago
    provoke a failure completely unrelated to normal use and so ... why bother? (wrt biology, not your programming equivalent)
justaman 11y ago
A similar study was done on chimps in the late 50's. Chimps were setup with a "oxygen mask" where, instead of oxygen, marijuana smoke was present. Ultimately they reported that the marijuana smoke killed the chimps rather than asphyxiation.

Raphmedia 11y ago

"So, like alcohol, another recreational drug that is legal in the US, marijuana is likely best avoided by pregnant women." This is so refreshing to see articles made with a neutral tone about marijuana and not the usual "IT'S EVIL" talk. It's a recreational drug like any other. You wouldn't drink when pregnant, you shouldn't smoke either. Those fact shouldn't be related at all about whether the substance is legal or not.

Shivetya 11y ago
except you can second hand inhale it, so there is an additional concern. That same concern occurs when you have children around. How much THC is in second hand smoke, let alone carcinogens and pollutants?
- oldmanjay 11y ago
  It's pretty intellectually difficult to extrapolate effects from heavily dosing pregnant mice into effects from microdosing pregnant humans. By which I mean your comment has no logical basis, only an emotional one. I explain this only so you understand the downvotes.
  - drzaiusapelord 11y ago
    Is it? When I was a kid second hand cigarette smoke was considered harmless. It certainly isn't today. We just don't the research because of restrictive laws banning it for the most part and the pro-pot acitvists disingenuous commentary about how "safe" it is. I feel like any politicized recreation substance will go down the path of cigarettes. Fanboys will claim its neutral, if not good for you, and then eventually the science and bias will shake out about its dangers. For example, we do know there's an increase for mental illness an decrease in IQ in kids who habitually smoke pot: https://today.duke.edu/2012/08/potiq https://today.duke.edu/2012/08/potiq Among a long-range study cohort of more than 1,000 New Zealanders, individuals who started using cannabis in adolescence and used it for years afterward showed an average decline in IQ of 8 points when their age 13 and age 38 IQ tests were compared. Quitting pot did not appear to reverse the loss either, said lead researcher Madeline Meier, a post-doctoral researcher at Duke University. The results appear online Aug. 27 in PNAS. The key variable in this is the age of onset for marijuana use and the brain's development, Meier said. Study subjects who didn't take up pot until they were adults with fully-formed brains did not show similar mental declines. --- So yes, pot can be harmless for a 21 year old, but not for a 15 year old. I'm all for legal pot, but only at age 21 or higher. I don't think the especially libertine attitudes we're seeing via web culture are helping. Its not harmless for certain age groups. We don't know enough about the brain and pot to make these types of assessments. Erring on the side of caution is the only rational path here and that includes making sure pregnant women aren't exposed to pot smoke.

meeper16 11y ago

I'd highly recommend listening to this experiment on how this truly works when considering epigentics: https://youtu.be/9DAcJSAM_BA?t=1764 https://youtu.be/9DAcJSAM_BA?t=1764

pil4rin 11y ago
Fantastic suggestion- I enjoyed this immensely. Thank you.
- meeper16 11y ago
  Your welcome. The whole field of epigentics is turning everything we know about biology on its side. It's amazing.

dismal2 11y ago

I don't see why they didn't just have them consume food with oil in it, this seems like a highly unnatural delivery mechanism. Relevant comment from Ars: > Interesting to note... If you look at the study > "THC (THC Pharm) was diluted in 0.9% NaCl (saline) solution containing 3% (vol/vol) DMSO and 2% (vol/vol) Tween-80 and administered intraperitoneally (i.p.) at a final dose of 3 mg/kg to pregnant females for 5 consecutive days, from E12.5 to E16.5. Control mice were injected with vehicle solution." > DMSO is TOXIC to developing brains. Its actually recommended not to use it in studies because it causes too much damage. > "The in vitro results suggest avoiding the use of BeOH (which also is more toxic than the other solvents in the in vivo test) and DMSO and using PEG400, EtOH and DMF even though the latter induced a body weight decrease in the B6D2F1 mouse strain. " > http://www.ncbi.nlm.nih.gov/pubmed/8011014 http://www.ncbi.nlm.nih.gov/pubmed/8011014 > It would seem as though they purposefully paired the THC with a solvent that would cause the relevant brain abnormalities.