AMPK activators
Happy Gringo 06 Mar 2010
Gradual basal skeletal muscle atrophy with age (sarcopenia) is perhaps even more clinically significant than diminished overload-induced growth. The fact that AMPK activity displays a five-fold increase with age in resting fast-twitch, but not slow-twitch, muscle (Figure 1)[25] led us to speculate that AMPK may partly underlie basal fast-twitch specific atrophy, an effect not testable by acute AMPK activation studies. Thus, we continuously activated AMPK in the resting muscles of young and old rats for 7 d (AICAR perfusion via osmotic pump and catheter). Importantly, we used slow-twitch soleus muscles for this experiment, hypothesizing that aged slow-twitch muscle (previously displaying neither elevated AMPK activity nor atrophy with age (Figure 1)[25] would exhibit sarcopenia-like properties if AMPK were chronically activated similar to aged fast-twitch muscle. As hypothesized, continuous AMPK activation elicited significant fiber atrophy in both young adult and old muscles (Figure 5). Moreover, an additional unexpected finding of continuously activating AMPK in resting muscle was a high frequency of fiber death (Figure 5).
(Enlarge Image) Figure 5. One week of continuous 5′-AMP-activated protein kinase (AMPK) activation causes fiber atrophy and death in slow-twitch soleus muscles of young adult (YA; 8 mo) and old (O; 30 mo) Fisher344 × Brown Norway F1 hybrid rats. Muscles were locally and continuously perfused (osmotic pump and catheter) with either 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR; an AMPK activator) at 0.5 mg·h-1 or vehicle (saline) during the 1-wk period. Fiber cross-sectional area was significantly (P ≤0.05) reduced in both age groups (by 25% in YA muscles and by 24% in O muscles; n = 3 per group). Images are representative muscle cross-sections stained with hematoxylin and eosin.
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Figure 5.
One week of continuous 5′-AMP-activated protein kinase (AMPK) activation causes fiber atrophy and death in slow-twitch soleus muscles of young adult (YA; 8 mo) and old (O; 30 mo) Fisher344 × Brown Norway F1 hybrid rats. Muscles were locally and continuously perfused (osmotic pump and catheter) with either 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR; an AMPK activator) at 0.5 mg·h-1 or vehicle (saline) during the 1-wk period. Fiber cross-sectional area was significantly (P ≤0.05) reduced in both age groups (by 25% in YA muscles and by 24% in O muscles; n = 3 per group). Images are representative muscle cross-sections stained with hematoxylin and eosin. The fiber atrophy induced by AMPK activation (Figure 5) agrees with findings that cultured myotube diameter is reduced under conditions in which AMPK activity is up-regulated[1] and supports the possibility that chronically elevated AMPK activity may contribute to basal fast-twitch fiber atrophy with age (sarcopenia). Suppression of muscle protein translation and synthesis[4,24] may be one mechanism by which AMPK exerts this effect; however, it is highly doubtful that solely suppressing protein synthesis would elicit the striking fiber atrophy and death observed in just 7 d (Figure 5). Thus, activation of protein degradation pathways is also a likely possibility. As previously mentioned, AMPK is known to stimulate muscle-specific lysosomal and proteasomal gene expression (FOXO, Atrogin-1, and MuRF1) as well as myofibrillar protein degradation.[15,17] The increased FOXO3A and MuRF1 mRNA expression and increased myofibrillar degradation with age in resting human muscle of mixed fiber types[21,28] may therefore result in part from elevated AMPK activity in the fast-twitch population. Interestingly, some have observed elevated rates of mixed[10] and myofibrillar[13] protein synthesis, along with higher S6K activation,[13] in aged rat fast-twitch muscle. Such a scenario would indicate a futile increase in protein synthesis rate in the face of an even faster degradation rate in these muscles, although still others have conversely observed lower basal protein synthesis in aged muscle.[29] Regardless of protein synthesis differences, an elevated protein degradation rate in aged fast-twitch muscle fibers likely plays a role in subtly, and over a long period of time, altering the synthesis-degradation balance toward gradual atrophy. We propose that chronically elevated AMPK activity may play a role in this phenomenon.
The possibility that continuously elevated AMPK activity affects the balance of myonuclear addition versus nuclear apoptosis in aged fast-twitch muscle is intriguing. Unfortunately, few data exist concerning AMPK's potential involvement in either phenomenon in skeletal muscle. Certainly, suppression of basal myonuclear addition cannot account for the rapidity with which AICAR induced fiber atrophy and death (Figure 5), and whether these effects were due to apoptotic mechanisms and/or more general fiber necrosis remains to be determined. However, AMPK does seem to play a key role in apoptotic signaling in mononucleated muscle cell types, including smooth muscle cells, cardiac myocytes, and immortalized (C2C12) skeletal myoblasts.[8,18] It is currently unclear whether AMPK is proapoptotic or antiapoptotic in these cells because there is somewhat equivocal evidence to support both.
In contrast to mononucleated cells, apoptosis in mature multinucleated skeletal muscle fibers does not necessarily mean fiber death but is more associated with fiber atrophy as the myonuclear domain volume remains relatively constant. It is unknown whether nuclear apoptosis leads to protein degradation and fiber atrophy or vice versa (i.e., fiber atrophy leads to nuclear apoptosis, which maintains a constant myonuclear domain volume). As might be expected, the frequency of apoptotic nuclei is well known to be increased in aged atrophying muscle fibers.[5] If AMPK is proapoptotic in mature muscle fibers similar to other muscle cell types under some conditions,[8] then chronically elevated AMPK activity (Figure 1)[25] may play a role in the age-related increase in apoptotic nuclei. In fact, we propose that any potential role of AMPK in aging multinucleated muscle fibers is more likely proapoptotic than antiapoptotic because of the following logic: 1) if myonuclear domain volume is to be kept constant, it is paradoxical to protect against nuclear death while selectively reducing protein synthesis and/or stimulating protein degradation; and 2) the potential antiapoptotic effects of AMPK in mononucleated cells is thought to enhance cell survival during times of brief energy deficit,[8] whereas apoptosis in multinucleated muscle fibers is more associated with atrophy than a risk of cell death (and lost nuclei can be replenished from the myogenic precursor cell pool when energy balance is restored). Moreover, although the extent of atrophy and/or nuclear apoptosis necessary to eventually achieve a "threshold" precipitating complete muscle fiber death is unknown, our data indicate a role for continuous AMPK activation in fiber atrophy and eventual fiber death, not fiber survival (Figure 5). Because fiber atrophy and death are also characteristics of sarcopenic muscle,[29] the potential role of AMPK in mediating apoptosis in aged skeletal muscle fibers, either directly or indirectly (via fiber atrophy and the loss of myonuclear domains) demands further exploration.
tunt01 06 Mar 2010
s123 07 Mar 2010
A good paper to read on AMPK activation is:
McCarty MF. Chronic activation of AMP-activated kinase as a strategy for slowing aging. Medical Hypotheses, 2004, 63: 334-339.
supernoober 30 Mar 2010
Logan 30 Mar 2010
What do you mean ALCAR converts fast twitch muscle to slow twitch? And why/how? I prefer fast twitch myself....
They are talking about AICAR not ALCAR.
http://www.google.co...0Tv2bLiR3wtPa9w
http://www.google.co...jHwyhMWi5cWSG-Q
chrono 25 Jul 2010
Acetyl-l-carnitine inhibits TNF-alpha-induced insulin resistance via AMPK pathway in rat skeletal muscle cells.
Zhang Z, Zhao M, Li Q, Zhao H, Wang J, Li Y.
Department of Nutrition and Food Hygiene, School of Public Health, Peking University
In this study, we demonstrated effects of acetyl-l-carnitine (ALC) on insulin resistance induced by tumor necrosis factor-alpha (TNF-alpha) in rat L6 cells. TNF-alpha downregulated insulin-stimulated glucose uptake and increased Serine 307 phosphorylation of insulin receptor substrate-1 (IRS-1). However, the treatment of ALC improved insulin-stimulated glucose uptake via AMP-activated protein kinase (AMPK) activation in a dose-dependent manner. Together, our data suggest that ALC inhibits TNF-alpha-induced insulin resistance through AMPK pathway in skeletal muscle cells.
PMID: 19121314 [PubMed - indexed for MEDLINE]
Logic 13 Sep 2014
http://www.sciencedi...550413109000904
ocean.soul 13 Sep 2014
If i take 500mg of alcar and then exercise the next day i cannot even move because of the muscle tension...
tunt01 13 Nov 2014
Gallic Acid activates AMPK/PGC1a/SIRT1.
Abstract
Gallic acid [3,4,5-trihydroxybenzoic acid (GA)], a natural phytochemical, is known to have a variety of cellular functions including beneficial effects on metabolic syndromes. However, the molecular mechanism by which GA exerts its beneficial effects is not known. Here we report that GA plays its role through the activation of AMP-activated protein kinase (AMPK) and by regulating mitochondrial function via the activation of peroxisome proliferator-activated receptor-γ coactivator1α (PGC1α). Sirtuin 1 (Sirt1) knockdown significantly blunted GA's effect on PGC1α activation and downstream genes, suggesting a critical role of the AMPK/Sirt1/PGC1α pathway in GA's action. Moreover, diet-induced obese mice treated with GA showed significantly improved glucose and insulin homeostasis. In addition, the administration of GA protected diet-induced body weight gain without a change in food intake. Biochemical analyses revealed a marked activation of AMPK in the liver, muscle, and interscapular brown adipose tissue of the GA-treated mice. Moreover, uncoupling protein 1 together with other genes related to energy expenditure was significantly elevated in the interscapular brown adipose tissue. Taken together, these results indicate that GA plays its beneficial metabolic roles by activating the AMPK/Sirt1/PGC1α pathway and by changing the interscapular brown adipose tissue genes related to thermogenesis. Our study points out that targeting the activation of the AMPK/Sirt1/PGC1α pathway by GA or its derivatives might be a potential therapeutic intervention for insulin resistance in metabolic diseases.
Dolph 13 Nov 2014
@prophets:
I did read that, too. It's surprising how many polyphenols have been shown to activate AMPK. I'm almost going as far that it seems difficult to find a polyphenol that does NOT have this effect. Could well be one of the reasons a polyphenol rich diet is associated with increased health span.
zorba990 03 Jan 2015
http://bvsalud.org/p...pt/mdl-22147657
"Allantoin, an active principle of yam, is documented to lower plasma glucose in diabetic rats. However, action mechanisms of allantoin remain obscure. It has been indicated that metformin shows ability to activate imidazoline I-2 receptors (I-2R) to lower blood sugar. Allantoin has also a chemical structure similar to metformin; both belong to guanidinium derivative. Thus, it is of special interest to know the effect of allantoin on I-2R. In the present study, the marked plasma glucose-lowering action of allantoin in streptozotocin-induced type-1 like diabetic rats was blocked by specific I-2R antagonist, BU224, in a dose-dependent manner. Also, the increase of ß-endorphin release by allantoin was blocked by BU224 in the same manner. Otherwise, amiloride at the dose sufficient to block I-2AR abolished the allantoin-induced ß-endorphin release and inhibited the blood glucose-lowering action of allantoin markedly but not completely. The direct effect of allantoin on glucose uptake in isolated skeletal muscle was also blocked by BU224. Also, the phosphorylation of AMPK in isolated skeletal muscle was raised by allantoin in a concentration-dependent manner. More-over, insulin sensitivity in diabetic rats was markedly increased by allantoin and this action was also blocked by BU224. These results suggest that allantoin has an ability to activate imidazoline I-2R while I-2AR is linked to the increase of ß-endorphin release and I-2BR is related to other actions including the influence in skeletal muscle for lowering of blood glucose in type-1 like diabetic rats. Thus, allantoin can be developed to treat diabetic disorders in the future.
Texto completo Documentos relacionados "
Edited by zorba990, 03 January 2015 - 04:19 PM.
BieraK 09 Mar 2015
Gallic Acid activates AMPK/PGC1a/SIRT1.
Abstract
Gallic acid [3,4,5-trihydroxybenzoic acid (GA)], a natural phytochemical, is known to have a variety of cellular functions including beneficial effects on metabolic syndromes. However, the molecular mechanism by which GA exerts its beneficial effects is not known. Here we report that GA plays its role through the activation of AMP-activated protein kinase (AMPK) and by regulating mitochondrial function via the activation of peroxisome proliferator-activated receptor-γ coactivator1α (PGC1α). Sirtuin 1 (Sirt1) knockdown significantly blunted GA's effect on PGC1α activation and downstream genes, suggesting a critical role of the AMPK/Sirt1/PGC1α pathway in GA's action. Moreover, diet-induced obese mice treated with GA showed significantly improved glucose and insulin homeostasis. In addition, the administration of GA protected diet-induced body weight gain without a change in food intake. Biochemical analyses revealed a marked activation of AMPK in the liver, muscle, and interscapular brown adipose tissue of the GA-treated mice. Moreover, uncoupling protein 1 together with other genes related to energy expenditure was significantly elevated in the interscapular brown adipose tissue. Taken together, these results indicate that GA plays its beneficial metabolic roles by activating the AMPK/Sirt1/PGC1α pathway and by changing the interscapular brown adipose tissue genes related to thermogenesis. Our study points out that targeting the activation of the AMPK/Sirt1/PGC1α pathway by GA or its derivatives might be a potential therapeutic intervention for insulin resistance in metabolic diseases.
Wow all in one... Two questions comes to my mind
1) Is gallic acid safe for human consumption?
2) What is the human dosage for AMPK/Sirt1/PGC1-alpha activation?
I've found a Korean ebay seller, 500 gr for 61 USD, the compound is sold like a chemical reagent for lab.
Here is another source in the US: www.ebay.com/itm/Gallic-Acid-Powder-three-100g-packages-300g-total-/171649946003?
This paper really caught my attention if GA works in humans like the paper shows in rats, this can be really significant for longevity and health issues.
Edited by BieraK, 09 March 2015 - 02:18 AM.
Darryl 10 Mar 2015
malbecman 10 Mar 2015
Just also keep an eye on the safety profile of any new formulation of DNP....the therapeutic index (or safety window) of that chemical is pretty small.
OTC, supplements & food compounds:aspirin & other salicylates - allosteric site activationa-Lipoic Acidberberine - respiratory chain complex I inhibitorresveratrol - F1 ATP synthase inhibitorepigallocatechin-3-gallate (EGCG) - F1 ATP synthase inhibitorquercetin - F1 ATP synthase inhibitorcurcumin - mitochondrial uncouplerhispidulin (Snow Lotus/Saussurea involucrata)glabridin (licorice extracts)cyanidincapsaicinbitter melon extractgarlic oilPrescription drugs:metformin - respiratory chain complex I inhibitorpioglitazone - respiratory chain complex I inhibitor, induces release of adiponectin by adipocytesphenobarbital - respiratory chain complex I inhibitorsalsalate - long half-life Rx salicylatetelmisartan - PPAR-γ agonist & angiotensin receptor blockerResearch chemicals:5-aminoimidazole-4-carboxamide riboside (AICAR, acadesine) - adenosine analogue metabolized to AMP mimetic ZMP2-deoxy-D-glucose - glycolysis inhibitoroligomycin - mitochondrial ATP synthase inhibitor2,4-dinitrophenol (DNP) - mitochondrial uncouplerA-769662 - allosteric activation at salicylate siteA-23187991PT1Endogenous activators:adiponectinleptinactivated protein Cciliary neurotrophic factorinterleukin-6 (IL-6)macrophage migrating inhibitory factor (MIF)hydrogen peroxidePersonally, I take high dose (~1 g/d) OTC magnesium salicylate (safer profile than aspirin) and low dose berberine (500 mg/d) in the context of a high polyphenol diet with intermittent fasting. Cost no object, I'd probably focus on salsalate, metformin, and telmisartan, and keep my eye peeled for news on extended/controlled release DNP.
Darryl 10 Mar 2015
Yeah, if controlled release DNP ever becomes a human drug, I'd be wary of generics.
Darryl 14 Mar 2015
Confirmation of synergistic effects between metformin and salicylate:
Rebecca, J. F., Morgan, D. F., Stephen, L. P., Emily, A. D., John, W. S., Jonathan, S. O., ... & Gregory, R. S. (2015). Metformin and salicylate synergistically activate liver AMPK, inhibit lipogenesis and improve insulin sensitivity. Biochemical Journal.
Metformin is the mainstay therapy for type 2 diabetes (T2D), and many patients also take salicylate-based drugs (i.e. Aspirin; ASA) for cardioprotection. Metformin and salicylate both increase AMP-activated protein kinase (AMPK) activity but by distinct mechanisms, with metformin altering cellular adenylate charge (increasing AMP) and salicylate interacting directly at the AMPK β1 drug binding site. AMPK activation by both drugs results in phosphorylation and inhibition of acetyl-CoA carboxylase (ACC), the rate limiting enzyme controlling fatty acid synthesis (lipogenesis). We find doses of metformin and salicylate used clinically synergistically activate AMPK in vitro and in vivo, resulting in reduced liver lipogenesis, lower liver lipid levels and improved insulin sensitivity in mice. Synergism occurs in cell free assays and is specific for the AMPK β1 subunit. These effects are also observed in primary human hepatocytes, and patients with dysglycemia exhibit additional improvements in a marker of insulin resistance (proinsulin) when treated with ASA and metformin compared to either drug alone. These data indicate that metformin-salicylate combination therapy may be efficacious for the treatment of non-alcoholic fatty liver disease and T2D.
PERSONALIZEDLongevityNut 26 Mar 2015
Gallic Acid activates AMPK/PGC1a/SIRT1.
Abstract
Gallic acid [3,4,5-trihydroxybenzoic acid (GA)], a natural phytochemical, is known to have a variety of cellular functions including beneficial effects on metabolic syndromes. However, the molecular mechanism by which GA exerts its beneficial effects is not known. Here we report that GA plays its role through the activation of AMP-activated protein kinase (AMPK) and by regulating mitochondrial function via the activation of peroxisome proliferator-activated receptor-γ coactivator1α (PGC1α). Sirtuin 1 (Sirt1) knockdown significantly blunted GA's effect on PGC1α activation and downstream genes, suggesting a critical role of the AMPK/Sirt1/PGC1α pathway in GA's action. Moreover, diet-induced obese mice treated with GA showed significantly improved glucose and insulin homeostasis. In addition, the administration of GA protected diet-induced body weight gain without a change in food intake. Biochemical analyses revealed a marked activation of AMPK in the liver, muscle, and interscapular brown adipose tissue of the GA-treated mice. Moreover, uncoupling protein 1 together with other genes related to energy expenditure was significantly elevated in the interscapular brown adipose tissue. Taken together, these results indicate that GA plays its beneficial metabolic roles by activating the AMPK/Sirt1/PGC1α pathway and by changing the interscapular brown adipose tissue genes related to thermogenesis. Our study points out that targeting the activation of the AMPK/Sirt1/PGC1α pathway by GA or its derivatives might be a potential therapeutic intervention for insulin resistance in metabolic diseases.
"Gallic acid is found in a number of land plants such as in gallnuts, sumac, witch hazel, tea leaves, oak bark, and other plants. It is also found in the aquatic plant Myriophyllum spicatum." From Wikipedia :-)