Mitofusins 1/2 and ERRalpha expression are increased in human skeletal muscle after physical exercise

Mitochondrial impairment is hypothesized to contribute to the pathogenesis of insulin resistance. Mitofusin (Mfn) proteins regulate the biogenesis and maintenance of the mitochondrial network, and when inactivated, cause a failure in the mitochondrial architecture and decreases in oxidative capacity and glucose oxidation. Exercise increases muscle mitochondrial content, size, oxidative capacity and aerobic glucose oxidation. To address if Mfn proteins are implicated in these exercise-induced responses, we measured Mfn1 and Mfn2 mRNA levels, pre-, post-, 2 and 24 h post-exercise. Additionally, we measured the expression levels of transcriptional regulators that control mitochondrial biogenesis and functions, including PGC-1alpha, NRF-1, NRF-2 and the recently implicated ERRalpha. We show that Mfn1, Mfn2, NRF-2 and COX IV mRNA were increased 24 h post-exercise, while PGC-1alpha and ERRalpha mRNA increased 2 h post-exercise. Finally, using in vitro cellular assays, we demonstrate that Mfn2 gene expression is driven by a PGC-1alpha programme dependent on ERRalpha. The PGC-1alpha/ERRalpha-mediated induction of Mfn2 suggests a role of these two factors in mitochondrial fusion. Our results provide evidence that PGC-1alpha not only mediates the increased expression of oxidative phosphorylation genes but also mediates alterations in mitochondrial architecture in response to aerobic exercise in humans

Footnotes January/February 2003, Vol.27, no. 1/2

Monthly newsletter for the State Library of Iowa

Footnotes January/February 2002, Vol.26 no.1/2

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Footnotes, January/February 2001, Vol.25, no.1/2

Monthly newsletter of State Library

1/2/20, arrivée de [Denis dit] Bertrand, [coureur belge] gagnant du cross de l'Intransigeant [au Bois de Boulogne, pelouse de la Muette] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 57832

Hottentottisch. Faces 1-2 : Nama, Bergdamaramundart : einzelne Wörter / gespr. von Missionar Baumann

[Traditions. Afrique du sud. Namibie. Khoïkhoï]

3-amino-1,2,4-triazole inhibits macrophage NO synthase.

Murine macrophages activated by interferon-gamma and lipopolysaccharide become leishmanicidal through a process involving L-arginine-derived nitrogen oxidation products. Both nitrite secretion and parasite killing by activated macrophages were inhibited by 3-amino-1,2,4-triazole as well as the related compound, 3-amino-1,2,4-triazine. Moreover, NO synthase activity in cytosolic extracts of activated cells was inhibited by both compounds. 4-amino-1,2,4-triazole, an isomer of 3-amino-1,2,4-triazole, was without effect. Our results suggest that besides its known inhibitory effect on catalases and peroxidases, 3-amino-1,2,4-triazole is an inhibitor of NO synthase. The resemblance between the tautomeric form of 3-amino-1,2,4-triazole and the guanidino group of L-arginine, the natural substrate for NO synthase, might be responsible for the observed inhibition.

Parc des Princes, 1-2-20, [rugby], équipe des Probables [armée française] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 57848

Parc des Princes, 1-2-20, rugby, équipe des Possibles [armée française] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 57847

[Stade] R[ue] Olivier de Serres [Paris, 15e arrondissement], 1-2-20, [football] association, équipe [de] l'Olympique Lillois : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 57846

1/2/20, [Denis dit] Bertrand, [coureur belge] gagnant du cross de l'Intransigeant [au Bois de Boulogne, pelouse de la Muette] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 57839

1/2/20, [Denis dit] Bertrand, [coureur belge] gagnant du cross de l'Intransigeant [au Bois de Boulogne, pelouse de la Muette] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 57837

1/2/20, départ du cross de l'Intransigeant [au Bois de Boulogne, pelouse de la Muette] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 57831

1/2/20, départ du cross de l'Intransigeant [au Bois de Boulogne, pelouse de la Muette] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 57830