Éditeur(s) : HAL CCSD Landes Bioscience
Résumé : International audience
In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
Autophagy

hal-00735751
https://hal.archives-ouvertes.fr/hal-00735751
PUBMED : 22966490

Éditeur(s) : HAL CCSD IOS Press
Résumé : International audience
This study tested the hypothesis that trained sickle cell trait (SCT) carriers are not subjected to greater risk of rhabdomyolysis or renal failure in response to moderate submaximal exercise than subjects with normal hemoglobin (CONT). Blood markers in 11 trained SCT carriers and 12 control counterparts were measured before and after 40 min of exercise at 55% of peak power output (Ppeak) conducted in thermoneutral environment. Body weights decreased with exercise in the same proportion in the two groups (from 65.1 ± 7.0 kg to 64.1 ± 7.0 kg and from 70.2 ± 6.6 to 68.6 ± 6.6 kg at the end of exercise in SCT and CONT, respectively). Heart rate and rectal temperature increased in the two groups in response to exercise, but the groups remained closely matched. Serum urea, CRP, CK and LDH were similar in the two groups and remained unchanged in response to exercise. Creatinine, Na + , K + , Cl − and myoglobin concentrations increased above baseline in response to exercise, with changes of the same magnitude in the two groups. In summary, the results of the present study suggest that moderate submaximal exercise is not unsafe from a biochemical point of view for sportsmen carrying SCT.
ISSN: 1386-0291

hal-01163943
https://hal.univ-antilles.fr/hal-01163943
DOI : 10.3233/CH-2011-1524