Cytochrome c mRNA and alpha-actin mRNA in muscles of rats fed beta-GPA

Lai, Mildred; Booth, Frank W.

doi:10.1152/jappl.1990.69.3.843

Cited by 21 publications

(16 citation statements)

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“…18.6 (SD 8.9) and 10.2% (SD 10.1) (Figure S1) [23]–[25], [28], [29], [34], [36], [43], [45], [48]–[50], [53], [54], [57], [59], [76], [82]. This apparent shift towards oxidative metabolism was accompanied by a 2-fold increase in mitochondrial DNA [20], and increased mitochondrial density [56], [78], with occasional subsarcolemmal accumulation of enlarged, elongated, or irregular shaped mitochondria, containing paracristalline inclusions [48], [54], [74], [81], [85], [86].…”

Section: Resultsmentioning

confidence: 99%

The Effect of the Creatine Analogue Beta-guanidinopropionic Acid on Energy Metabolism: A Systematic Review

2013

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BackgroundCreatine kinase plays a key role in cellular energy transport. The enzyme transfers high-energy phosphoryl groups from mitochondria to subcellular sites of ATP hydrolysis, where it buffers ADP concentration by catalyzing the reversible transfer of the high-energy phosphate moiety (P) between creatine and ADP. Cellular creatine uptake is competitively inhibited by beta-guanidinopropionic acid. This substance is marked as safe for human use, but the effects are unclear. Therefore, we systematically reviewed the effect of beta-guanidinopropionic acid on energy metabolism and function of tissues with high energy demands.MethodsWe performed a systematic review and searched the electronic databases Pubmed, EMBASE, the Cochrane Library, and LILACS from their inception through March 2011. Furthermore, we searched the internet and explored references from textbooks and reviews.ResultsAfter applying the inclusion criteria, we retrieved 131 publications, mainly considering the effect of chronic oral administration of beta-guanidinopropionic acid (0.5 to 3.5%) on skeletal muscle, the cardiovascular system, and brain tissue in animals. Beta-guanidinopropionic acid decreased intracellular creatine and phosphocreatine in all tissues studied. In skeletal muscle, this effect induced a shift from glycolytic to oxidative metabolism, increased cellular glucose uptake and increased fatigue tolerance. In heart tissue this shift to mitochondrial metabolism was less pronounced. Myocardial contractility was modestly reduced, including a decreased ventricular developed pressure, albeit with unchanged cardiac output. In brain tissue adaptations in energy metabolism resulted in enhanced ATP stability and survival during hypoxia.ConclusionChronic beta-guanidinopropionic acid increases fatigue tolerance of skeletal muscle and survival during ischaemia in animal studies, with modestly reduced myocardial contractility. Because it is marked as safe for human use, there is a need for human data.

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Section: Resultsmentioning

confidence: 99%

The Effect of the Creatine Analogue Beta-guanidinopropionic Acid on Energy Metabolism: A Systematic Review

2013

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“…In contrast to most metabolites, phosphorylation potential (ATP/ADP ϫ P i ) was found to be the only metabolic disturbance persistently depressed during the course of 50 days of continuous motor nerve stimulation, suggesting that cellular energy charge may be a key signaling factor to regulate activity-induced changes in gene expression (11,30). In rats, administration of the nonmetabolized creatine analog ␤-guanadinopropionic acid (␤-GPA) also reduces phosphorylation potential in skeletal muscle and, when administered over several weeks, results in marked increases in the expression of several metabolic genes (22,25,35,53). Similarly, skeletal muscle from mice in which the muscle-specific creatine kinase gene has been knocked out (KO) is characterized by lower ATP/ AMP ratios and increased mitochondrial content (43).…”

Section: Discussionmentioning

confidence: 99%

AMP-activated protein kinase activates transcription of the UCP3 and HKII genes in rat skeletal muscle

Stoppani

Hildebrandt

Sakamoto

et al. 2002

American Journal of Physiology-Endocrinology and Metabolism

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. AMP-activated protein kinase activates transcription of the UCP3 and HKII genes in rat skeletal muscle. Am J Physiol Endocrinol Metab 283: E1239-E1248, 2002. First published September 11, 2002 10.1152/ajpendo. 00278.2002.-AMP-activated protein kinase (AMPK) has recently emerged as a key signaling protein in skeletal muscle, coordinating the activation of both glucose and fatty acid metabolism in response to increased cellular energy demand. To determine whether AMPK signaling may also regulate gene transcription in muscle, rats were given a single subcutaneous injection (1 mg/g) of the AMP analog 5-aminoimidazole-4-carboxamide-1-␤-D-ribonucleoside (AICAR). AICAR injection activated (P Ͻ 0.05) AMPK-␣2 (ϳ2.5-fold) and transcription of the uncoupling protein-3 (UCP3, ϳ4-fold) and hexokinase II (HKII, ϳ10-fold) genes in both red and white skeletal muscle. However, AICAR injection also elicited (P Ͻ 0.05) an acute drop (60%) in blood glucose and a sustained (2-h) increase in blood lactate, prompting concern regarding the specificity of AICAR on transcription. To maximize AMPK activation in muscle while minimizing potential systemic counterregulatory responses, a single-leg arterial infusion technique was employed in fully conscious rats. Relative to saline-infused controls, single-leg arterial infusion of AICAR (0.125, 0.5, and 2.5 g ⅐ g Ϫ1 ⅐ min Ϫ1 for 60 min) induced a dose-dependent increase (2-to 4-fold, P Ͻ 0.05) in UCP3 and HKII transcription in both red and white skeletal muscle. Importantly, AICAR infusion activated transcription only in muscle from the infused leg and had no effect on blood glucose or lactate levels. These data provide evidence that AMPK signaling is linked to the transcriptional regulation of select metabolic genes in skeletal muscle.5-aminoimidazole-4-carboxamide ribonucleoside; single-leg arterial infusion; rat; AMP kinase phosphorylation AMP-ACTIVATED PROTEIN KINASE (AMPK) is a highly conserved metabolite-sensing protein kinase found in all eukaryotic cells (12). In mammals, the AMPK enzyme is composed of a catalytic ␣-subunit and two regulatory subunits, ␤ and ␥, each of which is encoded for by either two (␣ 1 , ␣ 2 , ␤ 1 , ␤ 2 ) (40, 42) or three (␥ 1 , ␥ 2 , ␥ 3 ) (6) genes. Although not completely defined, it is thought that AMP activates AMPK by binding to the interface between the ␣-and ␥-subunits, disrupting an autoinhibitory domain within the ␣-subunit (13). AMPK is also stimulated by phosphorylation of a regulatory site (Thr 172 ) in the catalytic domain of the ␣-subunit, a reaction catalyzed by an upstream kinase, AMPK kinase (AMPKK), which is also activated by AMP (14,15,41). Thus full activation of AMPK is achieved by a combination of AMP-mediated allosteric activation of AMPK and its upstream kinase AMPKK, and by covalent phosphorylation of the AMPK ␣-subunit by AMPKK. Although the resting concentration of AMP is typically 100-fold lower than ATP (a competitive inhibitor of AMPK), AMP concentration increases dramatically under conditions of accelerated ATP utilization,...

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“…Although these changes are well documented, the intracellular signaling pathways that mediate the changes in gene and protein expression are not understood. However, some of the changes in protein expression induced by endurance training are also produced by feeding rats ␤-guanidinoproprionic acid, a creatine analog that causes a fall in cellular ATP and phosphocreatine (28,31). This suggested that cellular energy charge might be one of the key signals.…”

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confidence: 99%

Effects of endurance training on activity and expression of AMP-activated protein kinase isoforms in rat muscles

Durante

Mustard

Park

et al. 2002

American Journal of Physiology-Endocrinology and Metabolism

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Hardie. Effects of endurance training on activity and expression of AMP-activated protein kinase isoforms in rat muscles. Am J Physiol Endocrinol Metab 283: E178-E186, 2002. First published March 12, 2002 10.1152/ajpendo.00404.2001.-The effects of endurance training on the response of muscle AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) to moderate treadmill exercise were examined. In red quadriceps, there was a large activation of ␣2-AMPK and inactivation of ACC in response to exercise. This response was greatly reduced after training, probably because of reduced metabolic stress. In white quadriceps, there were no effects of exercise on AMPK or ACC, but ␣2-activity was higher after training because of increased phosphorylation of Thr 172 . In soleus, there were small increases in ␣2-activity during exercise that were not affected by training. The expression of all seven AMPK subunit isoforms was also examined. The ␤2-and ␥2-isoforms were most highly expressed in white quadriceps, and ␥3 was expressed in red quadriceps and soleus. There was a threefold increase in expression of ␥3 after training in red quadriceps only. Our results suggest that ␥3 might have a special role in the adaptation to endurance exercise in muscles utilizing oxidative metabolism.

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Cytochrome c mRNA and alpha-actin mRNA in muscles of rats fed beta-GPA

Cited by 21 publications

References 0 publications

The Effect of the Creatine Analogue Beta-guanidinopropionic Acid on Energy Metabolism: A Systematic Review

The Effect of the Creatine Analogue Beta-guanidinopropionic Acid on Energy Metabolism: A Systematic Review

AMP-activated protein kinase activates transcription of the UCP3 and HKII genes in rat skeletal muscle

Effects of endurance training on activity and expression of AMP-activated protein kinase isoforms in rat muscles

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