The failure to extend lifespan via disruption of complex II is linked to preservation of dynamic control of energy metabolism

Mitochondrial succinate dehydrogenase function is essential for sperm motility and male fertility

Mitochondrial health is crucial to sperm quality and male fertility, but the precise role of mitochondria in sperm function remains unclear. SDHA is a component of the succinate dehydrogenase (SDH) complex and plays a critical role in mitochondria. In humans, SDH activity is positively correlated with sperm quality, and mutations in SDHA are associated with Leigh Syndrome. Here we report that the C. elegans SDHA orthologue SDHA-2 is essential for male fertility: sdha-2 mutants produce dramatically fewer offspring due to defective sperm activation and motility, have hyperfused sperm mitochondria, and disrupted redox balance. Similar sperm motility defects in sdha-1 and icl-1 mutant animals suggest an imbalance in metabolites may underlie the fertility defect. Our results demonstrate a role for SDHA-2 in sperm motility and male reproductive health and establish an animal model of SDH deficiency-associated infertility.

Hijacking Cellular Stress Responses to Promote Lifespan

Organisms are constantly exposed to stress both from the external environment and internally within the cell. To maintain cellular homeostasis under different environmental and physiological conditions, cell have adapted various stress response signaling pathways, such as the heat shock response (HSR), unfolded protein responses of the mitochondria (UPR^MT), and the unfolded protein response of the endoplasmic reticulum (UPR^ER). As cells grow older, all cellular stress responses have been shown to deteriorate, which is a major cause for the physiological consequences of aging and the development of numerous age-associated diseases. In contrast, elevated stress responses are often associated with lifespan extension and amelioration of degenerative diseases in different model organisms, including C. elegans. Activating cellular stress response pathways could be considered as an effective intervention to alleviate the burden of aging by restoring function of essential damage-clearing machinery, including the ubiquitin-proteosome system, chaperones, and autophagy. Here, we provide an overview of newly emerging concepts of these stress response pathways in healthy aging and longevity with a focus on the model organism, C. elegans.

Pleiotropic effects of mitochondria in aging

Aging is typified by a progressive decline in mitochondrial activity and stress resilience. Here, we review how mitochondrial stress pathways have pleiotropic effects on cellular and systemic homeostasis, which can comprise protective or detrimental responses during aging. We describe recent evidence arguing that defects in these conserved adaptive pathways contribute to aging and age-related diseases. Signaling pathways regulating the mitochondrial unfolded protein response, mitochondrial membrane dynamics, and mitophagy are discussed, emphasizing how their failure contributes to heteroplasmy and de-regulation of key metabolites. Our current understanding of how these processes are controlled and interconnected explains how mitochondria can widely impact fundamental aspects of aging.

The Unfolded Protein Responses in Health, Aging, and Neurodegeneration: Recent Advances and Future Considerations

Aging and age-related neurodegeneration are both associated with the accumulation of unfolded and abnormally folded proteins, highlighting the importance of protein homeostasis (termed proteostasis) in maintaining organismal health. To this end, two cellular compartments with essential protein folding functions, the endoplasmic reticulum (ER) and the mitochondria, are equipped with unique protein stress responses, known as the ER unfolded protein response (UPR ER ) and the mitochondrial UPR (UPR mt ), respectively. These organellar UPRs play roles in shaping the cellular responses to proteostatic stress that occurs in aging and age-related neurodegeneration. The loss of adaptive UPR ER and UPR mt signaling potency with age contributes to a feed-forward cycle of increasing protein stress and cellular dysfunction. Likewise, UPR ER and UPR mt signaling is often altered in age-related neurodegenerative diseases; however, whether these changes counteract or contribute to the disease pathology appears to be context dependent. Intriguingly, altering organellar UPR signaling in animal models can reduce the pathological consequences of aging and neurodegeneration which has prompted clinical investigations of UPR signaling modulators as therapeutics. Here, we review the physiology of both the UPR ER and the UPR mt , discuss how UPR ER and UPR mt signaling changes in the context of aging and neurodegeneration, and highlight therapeutic strategies targeting the UPR ER and UPR mt that may improve human health.

Succinate Dehydrogenase-Regulated Phosphoenolpyruvate Carboxykinase Sustains Copulation Fitness in Aging C. elegans Males

Dysregulated metabolism accelerates reduced decision-making and locomotor ability during aging. To identify mechanisms for delaying behavioral decline, we investigated how C. elegans males sustain their copulatory behavior during early to mid-adulthood. We found that in mid-aged males, gluco-/glyceroneogenesis, promoted by phosphoenolpyruvate carboxykinase (PEPCK), sustains competitive reproductive behavior. C. elegans' PEPCK paralogs, pck-1 and pck-2, increase in expression during the first 2 days of adulthood. Insufficient PEPCK expression correlates with reduced egl-2-encoded ether-a-go-go K+ channel expression and premature hyper-excitability of copulatory circuits. For copulation, pck-1 is required in neurons, whereas pck-2 is required in the epidermis. However, PCK-2 is more essential, because we found that epidermal PCK-2 likely supplements the copulation circuitry with fuel. We identified the subunit A of succinate dehydrogenase SDHA-1 as a potent modulator of PEPCK expression. We postulate that during mid-adulthood, reduction in mitochondrial physiology signals the upregulation of cytosolic PEPCK to sustain the male's energy demands.

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C. elegans upregulates pck-1- and pck-2-encoded PEPCK during early adulthood

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Loss of PEPCK causes premature male copulatory behavior decline

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Epidermal PEPCK is required to sustain the copulatory fitness

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Subunit A of succinate dehydrogenase antagonizes PEPCK expression

Multidimensional informatic deconvolution defines gender-specific roles of hypothalamic GIT2 in aging trajectories

In most species, females live longer than males. An understanding of this female longevity advantage will likely uncover novel anti-aging therapeutic targets. Here we investigated the transcriptomic responses in the hypothalamus - a key organ for somatic aging control - to the introduction of a simple aging-related molecular perturbation, i.e. GIT2 heterozygosity. Our previous work has demonstrated that GIT2 acts as a network controller of aging. A similar number of both total (1079-female, 1006-male) and gender-unique (577-female, 527-male) transcripts were significantly altered in response to GIT2 heterozygosity in early life-stage (2 month-old) mice. Despite a similar volume of transcriptomic disruption in females and males, a considerably stronger dataset coherency and functional annotation representation was observed for females. It was also evident that female mice possessed a greater resilience to pro-aging signaling pathways compared to males. Using a highly data-dependent natural language processing informatics pipeline, we identified novel functional data clusters that were connected by a coherent group of multifunctional transcripts. From these it was clear that females prioritized metabolic activity preservation compared to males to mitigate this pro-aging perturbation. These findings were corroborated by somatic metabolism analyses of living animals, demonstrating the efficacy of our new informatics pipeline.

Mitochondrial Subtype Identification and Characterization

Healthy, functional mitochondria are central to many cellular and physiological phenomena, including aging, metabolism, and stress resistance. A key feature of healthy mitochondria is a high membrane potential (Δψ) or charge differential (i.e., proton gradient) between the matrix and inner mitochondrial membrane. Mitochondrial Δψ has been extensively characterized via flow cytometry of intact cells, which measures the average membrane potential within a cell. However, the characteristics of individual mitochondria differ dramatically even within a single cell, and thus interrogation of mitochondrial features at the organelle level is necessary to better understand and accurately measure heterogeneity. Here we describe a new flow cytometric methodology that enables the quantification and classification of mitochondrial subtypes (via their Δψ, size, and substructure) using the small animal model C. elegans. Future application of this methodology should allow research to discern the bioenergetic and mitochondrial component in a number of human disease and aging models, including, C. elegans, cultured cells, small animal models, and human biopsy samples. © 2018 by John Wiley & Sons, Inc.

"High-Throughput Characterization of Region-Specific Mitochondrial Function and Morphology"

The tissue-specific etiology of aging and stress has been elusive due to limitations in data processing of current techniques. Despite that many techniques are high-throughput, they usually use singular features of the data (e.g. whole fluorescence). One technology at the nexus of fluorescence-based screens is large particle flow cytometry ("biosorter"), capable of recording positional fluorescence and object granularity information from many individual live animals. Current processing of biosorter data, however, do not integrate positional information into their analysis and data visualization. Here, we present a bioanalytical platform for the quantification of positional information ("longitudinal profiling") of C. elegans, which we posit embodies the benefits of both high-throughput screening and high-resolution microscopy. We show the use of these techniques in (1) characterizing distinct responses of a transcriptional reporter to various stresses in defined anatomical regions, (2) identifying regions of high mitochondrial membrane potential in live animals, (3) monitoring regional mitochondrial activity in aging models and during development, and (4) screening for regulators of muscle mitochondrial dynamics in a high-throughput format. This platform offers a significant improvement in the quality of high-throughput biosorter data analysis and visualization, opening new options for region-specific phenotypic screening of complex physiological phenomena and mitochondrial biology.

Identification and Characterization of Mitochondrial Subtypes in Caenorhabditis elegans via Analysis of Individual Mitochondria by Flow Cytometry

Mitochondrial bioenergetics has been implicated in a number of vital cellular and physiological phenomena, including aging, metabolism, and stress resistance. Heterogeneity of the mitochondrial membrane potential (Δψ), which is central to organismal bioenergetics, has been successfully measured via flow cytometry in whole cells but rarely in isolated mitochondria from large animal models. Similar studies in small animal models, such as Caenorhabditis elegans (C. elegans), are critical to our understanding of human health and disease but lack analytical methodologies. Here we report on new methodological developments that make it possible to investigate the heterogeneity of Δψ in C. elegans during development and in tissue-specific studies. The flow cytometry methodology described here required an improved collagenase-3-based mitochondrial isolation procedure and labeling of mitochondria with the ratiometric fluorescent probe JC-9. To demonstrate feasibility of tissue-specific studies, we used C. elegans strains expressing blue-fluorescent muscle-specific proteins, which enabled identification of muscle mitochondria among mitochondria from other tissues. This methodology made it possible to observe, for the first time, critical changes in Δψ during C. elegans larval development and provided direct evidence of the elevated bioenergetic status of muscle mitochondria relative to their counterparts in the rest of the organism. Further application of these methodologies can help tease apart bioenergetics and other biological complexities in C. elegans and other small animal models used to investigate human disease and aging.

A Screenable In Vivo Assay for Mitochondrial Modulators Using Transgenic Bioluminescent Caenorhabditis elegans

The multicellular model organism Caenorhabditis elegans is a small nematode of approximately 1 mm in size in adulthood that is genetically and experimentally tractable. It is economical and easy to culture and dispense in liquid medium which makes it well suited for medium-throughput screening. We have previously validated the use of transgenic luciferase expressing C. elegans strains to provide rapid in vivo assessment of the nematode’s ATP levels.^1-3 Here we present the required materials and procedure to carry out bioassays with the bioluminescent C. elegans strains PE254 or PE255 (or any of their derivative strains). The protocol allows for in vivo detection of sublethal effects of drugs that may identify mitochondrial toxicity, as well as for in vivo detection of potential beneficial drug effects. Representative results are provided for the chemicals paraquat, rotenone, oxaloacetate and for four firefly luciferase inhibitory compounds. The methodology can be scaled up to provide a platform for screening drug libraries for compounds capable of modulating mitochondrial function. Pre-clinical evaluation of drug toxicity is often carried out on immortalized cancerous human cell lines which derive ATP mostly from glycolysis and are often tolerant of mitochondrial toxicants.^4,5 In contrast, C. elegans depends on oxidative phosphorylation to sustain development into adulthood, drawing a parallel with humans and providing a unique opportunity for compound evaluation in the physiological context of a whole live multicellular organism.

Intestinal microbes influence the survival, reproduction and protein profile of Trichinella spiralis in vitro

The interactions between intestinal microbes and parasitic worms play an essential role in the development of the host immune system. However, the effects of gut microbes on Trichinella spiralis are unknown. The aim of this work was to explore microbe-induced alterations in the survival and reproduction of T. spiralis in vitro. To further identify the proteins and genes involved in the response of nematodes to microbes, quantitative proteomic analysis of T. spiralis was conducted by iTRAQ-coupled LCMS/MS technology and quantitative real-time-PCR was used to measure changes in mRNA expression. The results showed Lactobacillus acidophilus, and especially Lactobacillus bulgaricus, significantly enhanced the survival and reproductive rates of nematodes. Salmonella enterica, and especially Escherichia coli O157:H7 (EHEC), had opposite effects. Genetic responses were activated mainly by EHEC. A total of 514 proteins were identified and quantified, and carbohydrate metabolism-related proteins existed in a higher proportion. These findings indicated that some gut bacteria are friendly or harmful to humans and in addition they may have similar beneficial or detrimental effects on parasites. This may be due to the regulation of expression of specific genes and proteins. Our studies provide a basis for developing therapies against parasitic infections from knowledge generated by studying the gut microbes of mammals.

The Interplay Between Respiratory Supercomplexes and ROS in Aging

SIGNIFICANCE

The molecular mechanism of aging is still vigorously debated, although a general consensus exists that mitochondria are significantly involved in this process. However, the previously postulated role of mitochondrial-derived reactive oxygen species (ROS) as the damaging agents inducing functional loss in aging has fallen out of favor in the recent past. In this review, we critically examine the role of ROS in aging in the light of recent advances on the relationship between mitochondrial structure and function.

RECENT ADVANCES

The functional mitochondrial respiratory chain is now recognized as a reflection of the dynamic association of respiratory complexes in the form of supercomplexes (SCs). Besides providing kinetic advantage (channeling), SCs control ROS generation by the respiratory chain, thus providing a means to regulate ROS levels in the cell. Depending on their concentration, these ROS are either physiological signals essential for the life of the cell or toxic species that damage cell structure and functions.

CRITICAL ISSUES

We propose that under physiological conditions the dynamic nature of SCs reversibly controls the generation of ROS as signals involved in mitochondrial-nuclear communication. During aging, there is a progressive loss of control of ROS generation so that their production is irreversibly enhanced, inducing a vicious circle in which signaling is altered and structural damage takes place.

FUTURE DIRECTIONS

A better understanding on the forces affecting SC association would allow the manipulation of ROS generation, directing these species to their physiological signaling role.

The Energy Metabolism in Caenorhabditis elegans under The Extremely Low-Frequency Electromagnetic Field Exposure

A literal mountain of documentation generated in the past five decades showing unmistakable health hazards associated with extremely low-frequency electromagnetic fields (ELF-EMFs) exposure. However, the relation between energy mechanism and ELF-EMF exposure is poorly understood. In this study, Caenorhabditis elegans was exposed to 50 Hz ELF-EMF at intensities of 0.5, 1, 2, and 3 mT, respectively. Their metabolite variations were analyzed by GC-TOF/MS-based metabolomics. Although minimal metabolic variations and no regular pattern were observed, the contents of energy metabolism-related metabolites such as pyruvic acid, fumaric acid, and L-malic acid were elevated in all the treatments. The expressions of nineteen related genes that encode glycolytic enzymes were analyzed by using quantitative real-time PCR. Only genes encoding GAPDH were significantly upregulated (P < 0.01), and this result was further confirmed by western blot analysis. The enzyme activity of GAPDH was increased (P < 0.01), whereas the total intracellular ATP level was decreased. While no significant difference in lifespan, hatching rate and reproduction, worms exposed to ELF-EMF exhibited less food consumption compared with that of the control (P < 0.01). In conclusion, C. elegans exposed to ELF-EMF have enhanced energy metabolism and restricted dietary, which might contribute to the resistance against exogenous ELF-EMF stress.

The paradox of mitochondrial dysfunction and extended longevity

Mitochondria play numerous, essential roles in the life of eukaryotes. Disruption of mitochondrial function in humans is often pathological or even lethal. Surprisingly, in some organisms mitochondrial dysfunction can result in life extension. This paradox has been studied most extensively in the long-lived Mit mutants of the nematode Caenorhabditis elegans. In this review, we explore the major responses that are activated following mitochondrial dysfunction in these animals and how these responses potentially act to extend their life. We focus our attention on five broad areas of current research--reactive oxygen species signaling, the mitochondrial unfolded protein response, autophagy, metabolic adaptation, and the roles played by various transcription factors. Lastly, we also examine why disruption of complexes I and II differ in their ability to induce the Mit phenotype and extend lifespan.

Caenorhabditis elegans: A useful model for studying metabolic disorders in which oxidative stress is a contributing factor

Caenorhabditis elegans is a powerful model organism that is invaluable for experimental research because it can be used to recapitulate most human diseases at either the metabolic or genomic level in vivo. This organism contains many key components related to metabolic and oxidative stress networks that could conceivably allow us to increase and integrate information to understand the causes and mechanisms of complex diseases. Oxidative stress is an etiological factor that influences numerous human diseases, including diabetes. C. elegans displays remarkably similar molecular bases and cellular pathways to those of mammals. Defects in the insulin/insulin-like growth factor-1 signaling pathway or increased ROS levels induce the conserved phase II detoxification response via the SKN-1 pathway to fight against oxidative stress. However, it is noteworthy that, aside from the detrimental effects of ROS, they have been proposed as second messengers that trigger the mitohormetic response to attenuate the adverse effects of oxidative stress. Herein, we briefly describe the importance of C. elegans as an experimental model system for studying metabolic disorders related to oxidative stress and the molecular mechanisms that underlie their pathophysiology.

Do we age because we have mitochondria?

The process of aging remains a great riddle. Production of reactive oxygen species (ROS) by mitochondria is an inevitable by-product of respiration, which has led to a hypothesis proposing the oxidative impairment of mitochondrial components (e.g., mtDNA, proteins, lipids) that initiates a vicious cycle of dysfunctional respiratory complexes producing more ROS, which again impairs function. This does not exclude other processes acting in parallel or targets for ROS action in other organelles than mitochondria. Given that aging is defined as the process leading to death, the role of mitochondria-based impairments in those organ systems responsible for human death (e.g., the cardiovascular system, cerebral dysfunction, and cancer) is described within the context of "garbage" accumulation and increasing insulin resistance, type 2 diabetes, and glycation of proteins. Mitochondrial mass, fusion, and fission are important factors in coping with impaired function. Both biogenesis of mitochondria and their degradation are important regulatory mechanisms stimulated by physical exercise and contribute to healthy aging. The hypothesis of mitochondria-related aging should be revised to account for the limitations of the degradative capacity of the lysosomal system. The processes involved in mitochondria-based impairments are very similar across a large range of organisms. Therefore, studies on model organisms from yeast, fungi, nematodes, flies to vertebrates, and from cells to organisms also add considerably to the understanding of human aging.

The tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) induces mitochondrial and nuclear DNA damage in Caenorhabditis elegans

The metabolites of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) form DNA adducts in animal models. While there are many reports of formation of nuclear DNA adducts, one report also detected NNK-induced damage to the mitochondrial genome in rats. Using a different DNA damage detection technology, we tested whether this finding could be repeated in the nematode Caenorhabditis elegans. We treated N2 strain (wild-type) nematodes with NNK in liquid culture, and applied quantitative PCR to analyze NNK-induced nuclear and mitochondrial DNA (mtDNA) damage. Our results confirm that NNK causes both nuclear and mtDNA damage. However, we did not detect a difference in the level of nuclear versus mtDNA damage in C. elegans. To test whether the mtDNA damage was associated with mitochondrial dysfunction, we used a transgenic nematode strain that permits in vivo measurement of ATP levels and found lower levels of ATP in NNK-exposed animals when compared with the unexposed controls. To test whether the lower levels of ATP could be attributed to inhibition of respiratory chain components, we investigated oxygen consumption in whole C. elegans and found reduced oxygen consumption in exposed animals when compared with the unexposed controls. Our data suggest a model in which NNK exposure causes damage to both C. elegans nuclear and mitochondrial genomes, and support the hypothesis that the mitochondrial damage is functionally important in this model. These results also represent a first step in developing this genetically tractable organism as a model for assessing NNK toxicity.

The mitochondrial unfolded protein response, a conserved stress response pathway with implications in health and disease

The ability to respond to various intracellular and/or extracellular stresses allows the organism to adapt to changing environmental conditions and drives evolution. It is now well accepted that a progressive decline of the efficiency of stress response pathways occurs with aging. In this context, a correct proteostasis is essential for the functionality of the cell, and its dysfunction has been associated with protein aggregation and age-related degenerative diseases. Complex response mechanisms have evolved to deal with unfolded protein stress in different subcellular compartments and their moderate activation translates into positive effects on health. In this review, we focus on the mitochondrial unfolded protein response (UPR(mt)), a response to proteotoxic stress specifically in mitochondria, an organelle with a wide array of fundamental functions, most notably the harvesting of energy from food and the control of cell death. We compare UPR(mt) with the extensively characterized cytosolic heat shock response (HSR) and the unfolded protein response in endoplasmic reticulum (UPR(ER)), and discuss the current knowledge about UPR(mt) signaling pathways as well as their potential involvement in physiology.

Regulation of lifespan by the mitochondrial electron transport chain: reactive oxygen species-dependent and reactive oxygen species-independent mechanisms

SIGNIFICANCE

Aging is a consequence of the accumulation of cellular damage that impairs the capacity of an aging organism to adapt to stress. The Mitochondrial Free Radical Theory of Aging (MFRTA) has been one of the most influential ideas over the past 50 years. The MFRTA is supported by the accumulation of oxidative damage during aging along with comparative studies demonstrating that long-lived species or individuals produce fewer mitochondrial reactive oxygen species and have lower levels of oxidative damage.

RECENT ADVANCES

Recently, however, species that combine high oxidative damage with a longer lifespan (i.e., naked mole rats) have been described. Moreover, most of the interventions based on antioxidant supplementation do not increase longevity, as would be predicted by the MFRTA. Studies to date provide a clear understanding that mitochondrial function regulates the rate of aging, but the underlying mechanisms remain unclear.

CRITICAL ISSUES

Here, we review the reactive oxygen species (ROS)-dependent and ROS-independent mechanisms by which mitochondria can affect longevity. We discuss the role of different ROS (superoxide, hydrogen peroxide, and hydroxyl radical), both as oxidants as well as signaling molecules. We also describe how mitochondria can regulate longevity by ROS-independent mechanisms. We discuss alterations in mitochondrial DNA, accumulation of cellular waste as a consequence of glyco- and lipoxidative damage, and the regulation of DNA maintenance enzymes as mechanisms that can determine longevity without involving ROS.

FUTURE DIRECTIONS

We also show how the regulation of longevity is a complex process whereby ROS-dependent and ROS-independent mechanisms interact to determine the maximum lifespan of species and individuals.

Mitochondrial dysfunction in aging and longevity: a causal or protective role?

SIGNIFICANCE

Among the most highly investigated theories of aging is the mitochondrial theory of aging. The basis of this theory includes a central role for altered or compromised mitochondrial function in the pathophysiologic declines associated with aging. In general, studies in various organisms, including nematodes, rodents, and humans, have largely upheld that aging is associated with mitochondrial dysfunction. However, results from a number of studies directly testing the mitochondrial theory of aging by modulating oxidant production or scavenging in vivo in rodents have generally been inconsistent with predictions of the theory.

RECENT ADVANCES

Interestingly, electron transport chain mutations or deletions in invertebrates and mice that causes mitochondrial dysfunction paradoxically leads to enhanced longevity, further challenging the mitochondrial theory of aging.

CRITICAL ISSUES

How can mitochondrial dysfunction contribute to lifespan extension in the mitochondrial mutants, and what does it mean for the mitochondrial theory of aging?

FUTURE DIRECTIONS

It will be important to determine the potential mechanisms that lead to enhanced longevity in the mammalian mitochondrial mutants.

dj-1β regulates oxidative stress, insulin-like signaling and development in Drosophila melanogaster

DJ-1 (or PARK-7) is a multifunctional protein implicated in numerous pathologies including cancer, sterility and Parkinson disease (PD). The popular genetic model Drosophila melanogaster has two orthologs, dj-1: α and β. Dysfunction of dj-1β strongly impairs fly mobility in an age-dependent manner. In this study, we analyze in detail the molecular mechanism underlying the dj-1β mutant phenotype. Mitochondrial hydrogen peroxide production, but not superoxide production, was increased in mutant flies. An increase in peroxide leak from mitochondria causes oxidative damage elsewhere and explains the strong reduction in mobility caused by dj-1β mutation. However, at the same time, increased levels of hydrogen peroxide activated a pro-survival program characterized by (1) an alteration in insulin-like signaling, (2) an increase in mitochondrial biogenesis and (3) an increase in the de-acetylase activity of sirtuins. The activation of this pro-survival program was associated with increased longevity under conditions of moderate oxidative stress. Additionally, the dj-1β mutation unexpectedly accelerated development, a phenotype not previously associated with this mutation. Our results reveal an important role of dj-1β in oxidative stress handling, insulin-like signaling and development in Drosophila melanogaster.