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As a result of limited classes of anthelmintics and an over-reliance on chemical control, there is a great need to discover new compounds to combat drug resistance in parasitic nematodes. Here, we show that deguelin, a plant-derived rotenoid, selectively and potently inhibits the motility and development of nematodes, which supports its potential as a lead candidate for drug development. Furthermore, we demonstrate that deguelin treatment significantly increases gene transcription that is associated with energy metabolism, particularly oxidative phosphorylation and mito-ribosomal protein production before inhibiting motility. Mitochondrial tracking confirmed enhanced oxidative phosphorylation. In accordance, real-time measurements of oxidative phosphorylation in response to deguelin treatment demonstrated an immediate decrease in oxygen consumption in both parasitic (Haemonchus contortus) and free-living (Caenorhabditis elegans) nematodes. Consequently, we hypothesize that deguelin is exerting its toxic effect on nematodes as a modulator of oxidative phosphorylation. This study highlights the dynamic biologic response of multicellular organisms to deguelin perturbation.—Preston, S., Korhonen, P. K., Mouchiroud, L., Cornaglia, M., McGee, S. L., Young, N. D., Davis, R. A., Crawford, S., Nowell, C., Ansell, B. R. E., Fisher, G. M., Andrews, K. T., Chang, B. C. H., Gijs, M. A. M., Sternberg, P. W., Auwerx, J., Baell, J., Hofmann, A., Jabbar, A., Gasser, R. B. Deguelin exerts potent nematocidal activity via the mitochondrial respiratory chain.

We describe a microfluidic platform for the automated culture, treatment and long-term highresolution imaging of Caenorhabditis elegans nematodes under normal physiological conditions. Our device features: (i) a microfluidic design tailored for the isolation of L4 larvae from a mixed larval population and for successive culture and treatment; (ii) a worm immobilization method, based on the thermo-reversible gelation of a biocompatible polymer inside the microfluidic chip, thereby enabling high-resolution imaging; (iii) an integrated temperature control system, both to ensure viable environmental conditions for C. elegans culture and to steer the worm immobilization/release process.

Dysfunction of Paneth and goblet cells in the intestine contributes to inflammatory bowel disease (IBD) and colitis associated colorectal cancer (CAC). Here we report a role for the NAD+ dependent histone deacetylase SIRT1 in the control of anti bacterial defense. Mice with an intestinal specific Sirt1 deficiency (Sirt1int / ) have more Paneth and goblet cells with a consequent rearrangement of the gut microbiota. From a mechanistic point of view the effects on mouse intestinal cell maturation are mediated by SIRT1 dependent changes in the acetylation status of SPDEF a master regulator of Paneth and goblet cells. Our results suggest that targeting SIRT1 may be of interest in the management of IBD and CAC. © 2014 Lo Sasso et al.

Metabolic homeostasis requires that cellular energy levels are adapted to environmental cues. This adaptation is largely regulated at the transcriptional level, through the interaction between transcription factors, coregulators, and the basal transcriptional machinery. Coregulators, which function as both metabolic sensors and transcriptional effectors, are ideally positioned to synchronize metabolic pathways to environmental stimuli. The balance between inhibitory actions of corepressors and stimulatory effects of coactivators enables the fine-tuning of metabolic processes. This tight regulation opens therapeutic opportunities to manage metabolic dysfunction by directing the activity of cofactors toward specific transcription factors, pathways, or cells/tissues, thereby restoring whole-body metabolic homeostasis.

We present a multiplexed and automated microfluidic platform for phenotyping of C. elegans during their full lifespan and at high-throughput. We used the fluorescent hsp-6::gfp strain of worms and performed experiments to observe the effect of four different E. coli concentrations supplied for growth. We cultured worms in microfluidic chambers during their lifespan and quantified their motility. Nematodes were also confined at various time points inside tapered constriction channels for imaging to observe the mitochondrial stress, as expressed by fluorescence, and to measure their growth parameters as function of the amount of applied food.

The nematode Caenorhabditis elegans is increasingly used as a model for human biology. However, in vivo culturing platforms for C. elegans allowing high-content phenotyping during their life cycle in an automated fashion are lacking so far. Here, a multiplexed microfluidic platform for the rapid high-content phenotyping of populations of C. elegans down to single animal resolution is presented. Nematodes are (i) reversibly and regularly confined during their life inside tapered channels for imaging fluorescence signal expression and to measure their growth parameters, and (ii) allowed to freely move in microfluidic chambers, during which the swimming behavior was video-recorded. The obtained data sets are analyzed in an automated way and 19 phenotypic parameters are extracted. Our platform is employed for studying the effect of bacteria dilution, a form of dietary restriction (DR) in nematodes, on a worm model of Huntington's disease and demonstrates the influence of DR on disease regression.

Supplementary Information. (PDF 1126Â kb)

The present invention relates to methods of increasing lifespan, delaying aging, and/or preventing or treating an age-related disease or a mitochondrialdisease in a subject, comprising inducing a nuclear-mitochondrial OXPHOS protein dyssynchrony, including inhibiting the mitochondrial translation machinery function, as well as methods forscreening agents that are able to increase lifespan, inhibit or delay aging, and/or prevent or treat an age-related disease or disorder, or a mitochondrial disease or disorder, in a subject.

Supplementary Information. (PDF 1126Â kb)

The nematode Caernohabditis elegans is one of the most employed small model organisms in biology. Studies on transgenic animals often require the accurate observation of highly localized fluorescent signals inside the worms at high magnification, hence demanding the full immobilization of the animals. Moreover, in order to observe the dynamics of biological processes over the lifespan of a worm, the same worm has to be immobilized repeatedly, in a reversible manner and under normal physiological conditions. We describe a microfluidic platform for the automated culture, treatment and long-term high-resolution imaging of C. elegans. Our device features: (i) a microfluidic design tailored for the isolation of L4 larvae from a mixed larval population and for their successive culture and treatment; (ii) a worm immobilization method, based on the thermoreversible sol-gel transition of the biocompatible triblock copolymer Pluronic F127 inside the microfluidic chip, thereby enabling high-resolution imaging; (iii) an integrated temperature control system, both to ensure viable environmental conditions for C. elegans culture and to steer the worm immobilization/release process. We apply this device to observe mitochondrial dynamics in muscle cells during aging at single worm resolution. We expect our platform to enable the simultaneous study and repeated observation of multiple phenotypes in single worms or specific worm populations, such as lifespan and motility assays, in addition to high-resolution imaging.

We introduce a microfluidic platform for automated on-chip worm culture, creation of synchronized embryo microarrays, and long-term parallel live imaging of Caenorhabditis elegans embryos. Our device allows studying well-defined embryo populations at unprecedented spatio-temporal resolution, via fully automated multi-dimensional imaging, covering six independent dimensions: the 3 spatial coordinates, development time, exposure duration/type (brightfield, fluorescent), and embryo number in the microarray. We successfully employed our platform to investigate the impact of perturbations of the mitochondrial functions on C.elegans embryogenesis. Our analyses revealed that specific mitochondrial stresses trigger a mitochondrial unfolded protein response (UPRmt) in the embryos. These observations are the first proof that the UPRmt molecular pathway is functional during C.elegans embryogenesis.

The present invention provides methods of increasing muscle mass and muscle miochodrial oxidative metabolism. Additionally, the invention provides treating various disorders associated with mitochondrial dysfunction, including but not limited to metabolic disorders, muscular dystrophy disorders, neurodegenerative diseases, chronic inflammatory diseases, and diseases of aging.

We describe a microfluidic device for automated culture and long-term high resolution imaging of Caenorhabditis elegans nematodes, which we specifically employed as model organisms for the analysis of neurodegenerative disease progression. In this platform, we integrated: (i) a microfluidic design tailored for the confinement of worms at the L2 larval stage in separate culture chambers by means of passive hydrodynamics; (ii) an optimized protocol for worm feeding and progeny removal at desired rate, allowing follow-up of the same worms over long-term studies; (iii) a technique for reversible C.elegans immobilization, based on the thermoreversible gelation of Pluronic F127 (PF127) inside the microfluidic chip; (iv) active control of the device temperature; (v) a compact device assembly, suitable for automated multi-dimensional imaging on any upright or inverted microscope.