Am J Physiol Cell Physiol. 2010 Dec 29. [Epub ahead of print]
Prostaglandin F2{alpha} stimulates PI3K/ERK/mTOR signaling and skeletal myotube hypertrophy.
Markworth JF, Cameron-Smith D.
Abstract
Cyclooxygenase (COX) enzymes mediate the synthesis of pro-inflammatory prostaglandin (PG) species from cellular arachidonic acid. COX/PGs have been implicated in skeletal muscle growth/regeneration; however the mechanisms by which PGs influence skeletal muscle adaptation are poorly understood. The present study aimed to investigate PGF(2α) signaling and its role in skeletal myotube hypertrophy. PGF(2α) or the FP receptor agonist fluprostenol increased C2C12 myotube diameter. This effect was abolished by the FP receptor antagonist AL8810 or the mTOR inhibitor rapamycin. PGF(2α) stimulated time and dose dependant increases in the phosphorylation of ERK1/2 (Thr202/Tyr204), p70S6K (Thr389 & Thr421/Ser424) and eIF4G (Ser1108) without influencing Akt (Ser473). Pre-treatment with the phosphoinositide 3-kinase (PI3K) inhibitor LY294002 and the extracellular receptor kinase (ERK) inhibitor PD98059 blocked FP receptor signaling responses whilst rapamycin blocked heightened p70S6K/eIF4G phosphorylation without influencing ERK1/2 phosphorylation. These data suggest that activation of the FP receptor is coupled to C2C12 myotube growth and intracellular signaling via a PI3K/ERK/mTOR dependant pathway.
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01-17-2011, 10:11 AM #1
New Study on Arachidonic Acid! (More Good News)
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01-17-2011, 10:17 AM #2
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01-17-2011, 10:59 AM #3
I can't find in vivo concentrations of PGF2alpha after oral administration with a quick search (maybe it has never been studied).
Studies examining molecular signaling are interesting but like rhizome said of little relevance to real life.
I still maintain that there is no evidence that AA works, considering the major limitations in the Baylor study (see here). Positive testimonials could easily be explained by placebo effect; consider this study that found subjects who thought they were taking an anabolic steroid but were actually taking a placebo increased their bench press ~20-30 pounds over only a month. Considering MN advertises AA as a "steroid alternative" and all of the other mass and strength increasing claims, it isn't surprising that some people improve a lot (and this goes for any supplement). And this is why we need double-blinded studies.
It could work, but there simply isn't sufficient objective evidence yet.
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01-17-2011, 02:39 PM #4
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01-17-2011, 02:42 PM #5
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01-17-2011, 02:51 PM #6
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01-17-2011, 02:54 PM #7
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01-17-2011, 03:00 PM #8
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01-17-2011, 03:30 PM #9
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01-17-2011, 03:37 PM #10
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01-18-2011, 10:09 AM #11
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So your saying all of the positive feedback that ArA has gained is from a "placebo effect." Come on, most of these testamonial's clearly state what the consumer is visually seeing as well. Muscle fullness, increased vascularity, improved body comp.etc..
I do agree some of the strength claims (from any supplement) can be a placebo effect but that is not the only positive aspect being heard from supplementing with ArA.Sheepdog#60
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01-18-2011, 12:55 PM #12
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PGF2a is injected so I doubt there is any oral info out there but then again I havent looked at PGF2a in about 7 years. IIRC it has a half life of about 5mins when injected and a single tab of tylenol completely negates its effects.
What he is saying that if you use ACTUAL SCIENTIFIC data which is measurable instead of just people's responses there isnt enough information to suggest it works beyond what a placebo effect could give.Matt Cahill
www.DrivenSports.com
www.drivensports.co.uk
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01-20-2011, 10:01 PM #13
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01-27-2011, 07:09 AM #14
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01-29-2011, 11:14 PM #15
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01-30-2011, 09:36 PM #16
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01-30-2011, 10:05 PM #17
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01-31-2011, 11:03 PM #18
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01-31-2011, 11:05 PM #19
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02-01-2011, 03:05 AM #20
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02-01-2011, 03:00 PM #21
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02-01-2011, 08:44 PM #22
Over/under for how long it takes until this study is used to sell fish oil as a muscle builder http://www.ajcn.org/content/93/2/402.abstract
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02-01-2011, 08:57 PM #23
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02-02-2011, 08:27 AM #24
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02-02-2011, 08:44 AM #25
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02-02-2011, 08:51 AM #26
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02-02-2011, 11:48 AM #27
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02-02-2011, 05:19 PM #28
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my only concern is that consuming a pro inflammatory supplement will cause increase in inflammatory cytokines systemically and in all muscle, not just skeletal muscle. Short term maybe no big deal, but the long term effects have not been studied. Also, having a pro inflammatory state can lead to many morbidities. Yeah, im young and healthy now but i want to think about having a healthy future.
No bash, just discussing.Our greatest glory is not in never falling but in rising each and every time we fall
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02-02-2011, 05:27 PM #29
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02-02-2011, 06:00 PM #30
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I have attached a diagram & table. ArA is ingest then is biotransformed into PGs and LTs which have their effects carried out by chemical mediaters. Taking more of ArA will lead to more PG and LT. What do you mean by it is upstream?
Edit: i realize the table is too involved for the conversation, but its just to give the gist of my opinion.
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