Inactivation of GABAA receptor is related to heat shock stress response in organism model Caenorhabditis elegans

Carotenoids from mamey (Pouteria sapota) and carrot (Daucus carota) increase the oxidative stress resistance of Caenorhabditis elegans

Carotenoids are natural pigments and antioxidants found in fruits and vegetables such as carrot, tomato, orange, mango, yellow corn, pumpkin, and mamey. In this study, we evaluated the antioxidant potential of mamey (Pouteria sapota) carotenoids and compared them to carrot (Daucus carota) carotenoids. The carotenoids were extracted from mamey and carrot, and their antioxidant capacity were determined via in vitro (ABTS method) and in vivo assays (resistance against oxidative stress in Caenorhabditis elegans). The carotenoid contents in mamey and carrot were 4.42 ± 0.12 and 5.47 ± 0.04 mg β-carotene/100 g, respectively. Despite the differences between the carotenoid contents in both products (p < 0.05), the in vitro antioxidant capacity results showed no significant differences between the extracts (p > 0.05). The mamey and carrot carotenoid extracts decreased the oxidative damage in C. elegans by 20–30% and 30–40%, respectively. Both extracts increased the resistance and enhanced the survival of the nematodes, and showed better effects than pure β-carotene, probably owing to the complex mixture in the carotenoid extracts. These results suggest that mamey is a good alternative source of carotenoids and that it protects against oxidative stress in C. elegans. The protective effect of mamey carotenoids was similar to the effect of carrot carotenoids.

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Mamey carotenoids displayed similar antioxidant activity to carrot carotenoids.

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Mamey and carrot carotenoids increased the oxidative stress resistance of C. elegans.

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Continuous exposure to carotenoids enhanced the resistance of the progeny.

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Natural mixture of carotenoids had better antioxidant effects than pure β-carotene.

GABAergic system's Injuries Induced by Sodium Sulfite in Caenorhabditis elegans Were Prevented by the Anti-Oxidative Properties of Dehydroepiandrosterone Sulfate

Several pathophysiological processes involve Hypoxia conditions, where the nervous system is affected as well. We postulate that the GABAergic system is especially sensitive. Furthermore, drugs improving the resistance to hypoxia have been investigated, such as the neurosteroid dehydroepiandrosterone sulfate (DHEAS) which has shown beneficial effects in hypoxic processes in mammals; however, at the cellular level, its exact mechanism of action has yet to be fully elucidated. Here, we used a chemical hypoxia model through sodium sulfite (SS) exposure in Caenorhabditis elegans (C. elegans), a nematode whose response to hypoxia involves pathways and cellular processes conserved in mammals, and that allows study the direct effect of DHEAS without its conversion to sex hormones. This work aimed to determine the effect of DHEAS on damage to the GABAergic system associated with SS exposure in C. elegans. Worms were subjected to nose touch response (Not Assay) and observed in epifluorescence microscopy. DHEAS decreased the shrinkage response of Not Assay and the level of damage in GABAergic neurons on SS-exposed worms. Also, the enhanced nuclear localization of DAF-16 and consequently the overexpression of chaperone HSP-16.2 by hypoxia were significantly reduced in SS + DHEAS exposed worms. As well, DHEAS increased the survival rate of worms exposed to hydrogen peroxide. These results suggest that hypoxia-caused damage over the GABAergic system was prevented at least partially by DHEAS, probably through non-genomic mechanisms that involve its antioxidant properties related to its chemical structure.

Lonicera japonica extends lifespan and healthspan in Caenorhabditis elegans

Lonicera japonica (LJ) is widely used as the local medicine to improve body and prevent ills in China, but mechanisms of its healthy beneficial effects remain largely unclear. Here, we evaluated the anti-aging and healthspan promoting activities of 75% ethanol extract of LJ (LJ-E) in the animal model Caenorhabditis elegans. Our results showed that LJ-E (500 μg/mL) treatment enhanced the mean lifespan of worms by over 21.87% and significantly improved age-associated physiological functions in C. elegans. The 500 μg/mL concentration of LJ-E enhanced the survival rates under oxidative and thermal stresses, and decreased reactive oxygen species (ROS) levels and fat accumulation in the worms. Gene-specific mutant studies showed that LJ-E-mediated lifespan extension was dependent on mev-1, daf-2, daf-16, and hsf-1, but not eat-2 genes. LJ-E could upregulate stress-inducible genes, viz., hsp-16.2, sod-3 and mtl-1. Moreover, we found that the D1086.10 protein interacted with superoxide dismutase (SOD)-3 by functional protein association networks analysis according to RNA-sequencing results. It was confirmed that D1086.10 was needed to promote longevity, and positively regulated expression of sod-3 by using D1086.10 mutants. Furthermore, LJ-E significantly delayed amyloid β-protein induced paralysis in CL4176 strain. Given the important role of autophagy in aging and protein homeostasis, we observed that LJ-E could remarkably increase the mRNA expression of autophagy gene bec-1 in CL4176 strain, and decrease expression of autophagy substrate p62 protein by more than 40.0% in BC12921 strain. Finally, we found that combination composed of three major compounds (54 μg/mL chlorogenic acid, 15 μg/mL 1,5-dicaffeoylquinic acid and 7.5 μg/mL 1,3-dicaffeoylquinic acid) of 500 μg/mL LJ-E could significantly delay paralysis in CL4176 worms caused by Aβ toxicity, comparable to that of LJ-E. Overall, our study may have important implications in using Lonicera japonica to promote healthy aging and have a potency to design therapeutics for age-related diseases.