Zn²⁺ is required for the activity of many mitochondrial proteins, which regulate mitochondrial dynamics, apoptosis and mitophagy. However, it is not understood how the proper mitochondrial Zn²⁺ level is achieved to maintain mitochondrial homeostasis. Using Caenorhabditis elegans, we reveal here that a pair of mitochondrion-localized transporters controls the mitochondrial level of Zn²⁺. We demonstrate that SLC-30A9/ZnT9 is a mitochondrial Zn²⁺ exporter. Loss of SLC-30A9 leads to mitochondrial Zn²⁺ accumulation, which damages mitochondria, impairs animal development and shortens the life span. We further identify SLC-25A25/SCaMC-2 as an important regulator of mitochondrial Zn²⁺ import. Loss of SLC-25A25 suppresses the abnormal mitochondrial Zn²⁺ accumulation and defective mitochondrial structure and functions caused by loss of SLC-30A9. Moreover, we reveal that the endoplasmic reticulum contains the Zn²⁺ pool from which mitochondrial Zn²⁺ is imported. These findings establish the molecular basis for controlling the correct mitochondrial Zn²⁺ levels for normal mitochondrial structure and functions.
Animals ; Caenorhabditis elegans/metabolism* ; Cation Transport Proteins/genetics* ; Homeostasis ; Mitochondria/metabolism* ; Zinc/metabolism*

OBJECTIVE: To investigate the changes of lipid metabolism and stress response of adult C.elegans exposed to non-freezing low temperature and explore the possible mechanism. METHODS: The survival rate and activity of adult C.elegans cultured at 20℃ or 4℃ were observed.Lipid metabolism of the cultured adult C.elegans was evaluated using oil red O staining and by detecting the expressions of the genes related with lipid metabolism.The effects of low temperature exposure on stress level of adult C.elegans were evaluated using mitochondrial fluorescence staining and by detecting the expression levels of stress-related genes and antioxidant genes at both the mRNA and protein levels. RESULTS: The lifespan and activity of adult C.elegans exposed to low temperature were significantly reduced with decreased lipid accumulation (P < 0.05) and decreased expressions of genes related with fatty acid synthesis and metabolism (fat-5, fat-6, fat-7, fasn-1, nhr-49, acs-2 and aco-1;P < 0.01).Cold stress significantly increased the expressions of heat shock proteins hsp-70 and hsp16.2(P < 0.05) but lowered the number of mitochondria (P < 0.0001) and the expressions of atfs-1, sod-2, sod-3 and gpx-1(P < 0.05).Knockout of fat-5, nhr-49 or both fat-5 and fat-6 obviously enhanced the sensitivity of C.elegans to cold stress as shown by further reduced activity (P < 0.05) and reduced survival rate at 24 h (P < 0.0001) under cold stress. CONCLUSION Exposure to a low temperature at 4℃ results in lowered lipid metabolism of adult C.elegans accompanied by a decreased mitochondrial number and quality control ability, which triggers high expressions of stress-related genes and causes reduction of antioxidant capacity, thus callsing lowered activity and reduced lifespan of C.elegans.
Animals ; Antioxidants/metabolism* ; Caenorhabditis elegans ; Caenorhabditis elegans Proteins/genetics* ; Cold-Shock Response ; Lipid Metabolism ; Lipid Metabolism Disorders ; Longevity/genetics*

OBJECTIVE: This study explored the rejuvenation mechanisms of Thai polyherbal medicines using different approaches, including in vitro methods, as well as a well-defined nematode model, Caenorhabditis elegans. METHODS: THP-R-SR012 decoction was selected from 23 polyherbal medicines, based on metal-chelating and chain-breaking antioxidant capacities. The influences of this extract on the survival and some stress biomarkers of C. elegans under paraquat-induced oxidative stress were evaluated. Furthermore, lifespan analysis and levels of lipofuscin accumulation were examined in senescent nematodes. The phytochemical profile of THP-R-SR012 was analyzed. RESULTS: Supplementation with THP-R-SR012 decoction significantly increased the mean lifespan and reduced the oxidative damage to C. elegans under oxidative stress conditions. Further, THP-R-SR012 supplementation slightly influenced the lifespan and the level of lipofuscin accumulation during adulthood. Antioxidant-related phytochemical constituents of THP-R-SR012 decoction were rutin, naringenin, 3,4-dihydroxybenzoic acid, gallic acid, glycyrrhizic acid, demethoxycurcumin and 18α-glycyrrhetinic acid. CONCLUSION The antioxidant potential of THP-R-SR012 was due to its scavenging properties, its enhancement of antioxidant-related enzyme activities, and the presence of the antioxidant-related compound. These results support the traditional use of THP-R-SR012 decoction as a tonic for nourishing and strengthening the whole body.
Animals ; Antioxidants/pharmacology* ; Caenorhabditis elegans/metabolism* ; Caenorhabditis elegans Proteins/metabolism* ; Oxidative Stress ; Plant Extracts/pharmacology* ; Reactive Oxygen Species ; Rejuvenation ; Thailand

Oxygen levels are unequal in different living geographical locations of human and related to normal physiology of health. The reduction of oxygen level in the body can lead to a variety of diseases, such as stroke caused by cerebral ischemia and hypoxia. In the recent years, many studies have elucidated the molecular and cellular mechanisms of organism response to different oxygen concentrations by using the nematode Caenorhabditis elegans (C. elegans) as model organism. C. elegans can escape hypoxia or hyperoxia and adapt to the ambient oxygen environments, and there are different response and regulation mechanisms in different degrees of hypoxia environment. In this paper, recent advances in the reaction of nematodes to different oxygen concentrations and the underlying mechanism were reviewed.
Animals ; Caenorhabditis elegans ; Caenorhabditis elegans Proteins ; Humans ; Hypoxia ; Oxygen

In this study, we aimed to evaluate the toxic effects, changes in life span, and expression of various metabolism-related genes in Caenorhabditis elegans, using RNA interference (RNAi) and mutant strains, after 3-bromopyruvate (3-BrPA) treatment. C. elegans was treated with various concentrations of 3-BrPA on nematode growth medium (NGM) plates, and their survival was monitored every 24 h. The expression of genes related to metabolism was measured by the real-time fluorescent quantitative polymerase chain reaction (qPCR). Nematode survival in the presence of 3-BrPA was also studied after silencing three hexokinase (HK) genes. The average life span of C. elegans cultured on NGM with 3-BrPA was shortened to 5.7 d compared with 7.7 d in the control group. hxk-1, hxk-2, and hxk-3 were overexpressed after the treatment with 3-BrPA. After successfully interfering hxk-1, hxk-2, and hxk-3, the 50% lethal concentration (LC₅₀) of all mutant nematodes decreased with 3-BrPA treatment for 24 h compared with that of the control. All the cyp35 genes tested were overexpressed, except cyp-35B3. The induction of cyp-35A1 expression was most obvious. The LC₅₀ values of the mutant strains cyp-35A1, cyp-35A2, cyp-35A4, cyp-35B3, and cyp-35C1 were lower than that of the control. Thus, the toxicity of 3-BrPA is closely related to its effect on hexokinase metabolism in nematodes, and the cyp-35 family plays a key role in the metabolism of 3-BrPA.
Animals ; Caenorhabditis elegans/metabolism* ; Caenorhabditis elegans Proteins/genetics* ; Cytochrome P-450 Enzyme System/genetics* ; Hexokinase/physiology* ; Pyruvates/toxicity* ; RNA, Messenger/analysis*

Sec61β, a subunit of the Sec61 translocon complex, is not essential in yeast and commonly used as a marker of endoplasmic reticulum (ER). In higher eukaryotes, such as Drosophila, deletion of Sec61β causes lethality, but its physiological role is unclear. Here, we show that Sec61β interacts directly with microtubules. Overexpression of Sec61β containing small epitope tags, but not a RFP tag, induces dramatic bundling of the ER and microtubule. A basic region in the cytosolic domain of Sec61β is critical for microtubule association. Depletion of Sec61β induces ER stress in both mammalian cells and Caenorhabditis elegans, and subsequent restoration of ER homeostasis correlates with the microtubule binding ability of Sec61β. Loss of Sec61β causes increased mobility of translocon complexes and reduced level of membrane-bound ribosomes. These results suggest that Sec61β may stabilize protein translocation by linking translocon complex to microtubule and provide insight into the physiological function of ER-microtubule interaction.
Animals ; COS Cells ; Caenorhabditis elegans Proteins ; genetics ; metabolism ; Cell Line, Tumor ; Cercopithecus aethiops ; Endoplasmic Reticulum ; metabolism ; Homeostasis ; Humans ; Microtubules ; metabolism ; SEC Translocation Channels ; deficiency ; genetics ; metabolism

In order to discover lifespan-extending compounds made from natural resources, activity-guided fractionation of Zingiber officinale Roscoe (Zingiberaceae) ethanol extract was performed using the Caenorhabditis elegans (C. elegans) model system. The compound 6-gingerol was isolated from the most active ethyl acetate soluble fraction, and showed potent longevity-promoting activity. It also elevated the survival rate of worms against stressful environment including thermal, osmotic, and oxidative conditions. Additionally, 6-gingerol elevated the antioxidant enzyme activities of C. elegans, and showed a dose-depend reduction of intracellular reactive oxygen species (ROS) accumulation in worms. Further studies demonstrated that the increased stress tolerance of 6-gingerol-mediated worms could result from the promotion of stress resistance proteins such as heat shock protein (HSP-16.2) and superoxide dismutase (SOD-3). The lipofuscin levels in 6-gingerol treated intestinal worms were decreased in comparison to the control group. No significant 6-gingerol-related changes, including growth, food intake, reproduction, and movement were noted. These results suggest that 6-gingerol exerted longevity-promoting activities independently of these factors and could extend the human lifespan.
Caenorhabditis elegans* ; Caenorhabditis* ; Eating ; Ethanol ; Ginger* ; Heat-Shock Proteins ; Humans ; Lipofuscin ; Longevity* ; Natural Resources ; Reactive Oxygen Species ; Reproduction ; Superoxide Dismutase ; Survival Rate

The present study investigated the effects and underlying mechanism of ethylacetate fraction of Ribes fasciculatum (ERF) on the lifespan and stress tolerance using a Caenorhabditis elegans model. The longevity activity of ERF was determined by lifespan assay under normal culture condition. The survival rate of nematodes under various stress conditions was assessed to validate the effects of ERF on the stress tolerance. To determine the antioxidant potential of ERF, the superoxide dismutase (SOD) activities and intracellular reactive oxygen species (ROS) levels were investigated. The ERF-mediated change in SOD-3 expression was examined using GFP-expressing transgenic strain. The effects of ERF on the aging-related factors were investigated by reproduction assay and pharyngeal pumping assay. The intestinal lipofuscin levels of aged nematodes were also measured. The mechanistic studies were performed using selected mutant strains. Our results indicated that ERF showed potent lifespan extension effects on the wild-type nematode under both normal and various stress conditions. The ERF treatment also enhanced the activity and expression of superoxide dismutase (SOD) and attenuated the intracellular ROS levels. Moreover, ERF-fed nematodes showed decreased lipofuscin accumulation, indicating ERF might affect age-associated changes in C. elegans. The results of mechanistic studies indicated that there was no significant lifespan extension in ERF-treated daf-2, age-1, sir-2.1, and daf-16 null mutants, suggesting that they were involved in ERF-mediated lifespan regulation. In conclusion, R. fasciculatum confers increased longevity and stress resistance in C. elegans via SIR-2.1-mediated DAF-16 activation, dependent on the insulin/IGF signaling pathway.
Aging ; drug effects ; genetics ; metabolism ; Animals ; Caenorhabditis elegans ; drug effects ; genetics ; growth & development ; metabolism ; Caenorhabditis elegans Proteins ; genetics ; metabolism ; Humans ; Longevity ; drug effects ; Oxidative Stress ; drug effects ; Plant Extracts ; pharmacology ; Reactive Oxygen Species ; metabolism ; Ribes ; chemistry ; Signal Transduction ; drug effects

Reproduction, fat metabolism, and longevity are intertwined regulatory axes; recent studies in C. elegans have provided evidence that these processes are directly coupled. However, the mechanisms by which they are coupled and the reproductive signals modulating fat metabolism and lifespan are poorly understood. Here, we find that an oogenesis-enriched gene, c30f12.4, is specifically expressed and located in germ cells and early embryos; when the gene is knocked out, oogenesis is disrupted and brood size is decreased. In addition to the reproductive phenotype, we find that the loss of c30f12.4 alters fat metabolism, resulting in decreased fat storage and smaller lipid droplets. Meanwhile, c30f12.4 mutant worms display a shortened lifespan. Our results highlight an important role for c30f12.4 in regulating reproduction, fat homeostasis, and aging in C. elegans, which helps us to better understand the relationship between these processes.
Animals ; Caenorhabditis elegans ; genetics ; metabolism ; Caenorhabditis elegans Proteins ; genetics ; metabolism ; Female ; Lipid Droplets ; metabolism ; Lipid Metabolism ; physiology ; Longevity ; physiology ; Mutation ; Oogenesis ; physiology

The seed of Vigna angularis has long been cultivated as a food or a folk medicine in East Asia. Genistein (4',5,7-trihydroxyisoflavone), a dietary phytoestrogen present in this plant, has been known to possess various biological properties. In this study, we investigated the possible lifespan-extending effects of genistein using Caenorhabditis elegans model system. We found that the lifespan of nematode was significantly prolonged in the presence of genistein under normal culture condition. In addition, genistein elevated the survival rate of nematode against stressful environment including heat and oxidative conditions. Further studies demonstrated that genistein-mediated increased stress tolerance of nematode could be attributed to enhanced expressions of stress resistance proteins such as superoxide dismutase (SOD-3) and heat shock protein (HSP-16.2). Moreover, we failed to find genistein-induced significant change in aging-related factors including reproduction, food intake, and growth, indicating genistein exerts longevity activity independent of affecting these factors. Genistein treatment also led to an up-regulation of locomotory ability of aged nematode, suggesting genistein affects healthspan as well as lifespan of nematode. Our results represent that genistein has beneficial effects on the lifespan of C. elegans under both of normal and stress condition via elevating expressions of stress resistance proteins.
Caenorhabditis elegans* ; Eating ; Far East ; Genistein* ; Heat-Shock Proteins ; Hot Temperature ; Longevity ; Medicine, Traditional ; Phytoestrogens ; Plants ; Reproduction ; Superoxide Dismutase ; Survival Rate ; Up-Regulation