Lifespan Extension Induced by Caffeine in Caenorhabditis elegans is Partially Dependent on Adenosine Signaling

Caffeine is a widely used psychoactive substance. Studies have shown that caffeine may play a protective role in aging-associated disorders. However, the mechanisms by which caffeine modulates aging are not yet clear. In this study, we have shown that caffeine increases Caenorhabditis elegans lifespan, delays its larval development, reduces reproduction and body length. These phenotypes were partly reversed by worm’s exposure to adenosine, which suggest a putative common target. Moreover, they were dependent on a functional insulin/IGF-1-like pathway. Our results may shed light on new genetic determinants of aging

Behavioral and metabolic effects of the atypical antipsychotic ziprasidone on the nematode Caenorhabditis elegans.

Atypical antipsychotics are associated with metabolic syndrome, primarily associated with weight gain. The effects of Ziprasidone, an atypical antipsychotic, on metabolic syndrome has yet to be evaluated. Here in, we evaluated lipid accumulation and behavioral changes in a new experimental model, the nematode Caenorhabditis elegans (C. elegans). Behavioral parameters in the worms were evaluated 24 h after Ziprasidone treatment. Subsequently, lipid accumulation was examined using Nile red, LipidTox green and BODIPY labeling. Ziprasidone at 40 µM for 24 h effectively decreased the fluorescence labeling of all markers in intestinal cells of C. elegans compared to control (0.16% dimethyl sulfoxide). Ziprasidone did not alter behaviors related to energetic balance, such as pharynx pumping, defecation cycles and movement. There was, however, a reduction in egg-production, egg-laying and body-length in nematodes exposed to Ziprasidone without any changes in the progression of larval stages. The serotoninergic pathway did not appear to modulate Ziprasidone's effects on Nile red fluorescence. Additionally, Ziprasidone did not alter lipid accumulation in daf-16 or crh-1 deletion mutants (orthologous of the transcription factors DAF-16 and CREB, respectively). These results suggest that Ziprasidone alters reproductive behavior, morphology and lipid reserves in the intestinal cells of C. elegans. Our results highlight that the DAF-16 and CREB transcription factors are essential for Ziprasidone-induced fat store reduction

<i>Nile</i><i>Red</i> Fluorescence reduction in <i>Caenorhabditis elegans</i> wild-type (N2) after Ziprasidone treatment for 24h.

<p>(A) Representative images of Ziprasidone treatment; (B) dose-response curve to Ziprasidone. A set of optical sections of 2.52 mm through the specimen (called a "Z series") of the first intestinal pair cells. The control group correspond to DMSO 0.16% in Acetic acid (1:10 000). The results were expressed in percentage of control (mean of fluorescence, standard deviation (SD), n>15). * p<0.05; ***p<0.0001 statistically different when compared to control 24h by one way ANOVA with Bonferroni correction for post hoc multiple comparisons.</p

Recover of lipid profile through <i>Nile Red</i> labeling in mutants to <i>daf-16</i> and <i>crh-1</i> transcription factors after Ziprasidone treatment (40 µM).

<p>(A) Representative images of <i>Nile </i><i>Red</i> fluorescence and (B) fluorescence amount in <i>C. elegans</i> mutants (<i>daf-16, crh-1</i>) and wild-type (N2). The results were expressed in percentage of control (DMSO 0.16% in Acetic acid (1:10 000)). ***p<0.0001, statistically different compared to the control by one way ANOVA with Bonferroni correction for <i>post </i><i>hoc</i> multiple comparisons (mean of fluorescence, SD, n>25).</p

<i>Caenorhabditis elegans</i> wild-type (N2) perimeter after Ziprasidone treatment for 24, 48 and 72 hours.

<p>(A) Representative images of worms and (B) the perimeter quantification in µm after 24, 48 and 72 hours of Ziprasidone (40 µM) or vehicle control (DMSO 0.16% in Acetic acid (1:10 000)) exposition. After the determined times, the worms were removed of the plates and the images acquired with a stereoscope (40x, Nikon SMZ 1500 Stereoscope microscope). Statistically different compared to the respective control of each time (**p<0.001; ***p<0.0001, by Student’s T-test, mean, SD, n>20). The assays were confirmed twice.</p

Effects on lipid stores after exogenous exposition to the monoamines and Ziprasidone in wild-type worms (N2).

<p>The nematodes were exposed to the monoamines (A) tyramine (TA, 5 mM), (B) dopamine (DA, 5 mM), (C) octopamine (AO, 5 mM) and (D) serotonin (5-HT, 5mM) isolated or concomitant to the Ziprasidone (40 µM). The fat amount was evaluated using <i>Nile </i><i>Red</i> labeling follow density quantification in the first intestinal pair cells. The results were expressed in percentage of respective control: HCl 0.1N (compared to the monoamines), DMSO (0.16% in Acetic acid (1:10 000), compared to the Ziprasidone group) and HCl + DMSO (compared to the monoamine + Ziprasidone association). *p<0.05; **p<0.01; ***p<0.001, statistically different compared to the respective control by one way ANOVA with Bonferroni correction for <i>post </i><i>hoc</i> multiple comparisons (% of control, SD, n=20).</p

<i>C. elegans</i> larval development after Ziprasidone exposition.

<p>The worms were treated with Ziprasidone (40 µM) or control (DMSO 0.16% in Acetic acid (1:10 000)) after L1 larval stage until gravid adult. The results were evaluated by two way ANOVA no significant differences between groups were found (% worms in the larval stage, n=20).</p