Capsaicinoid-Glucosides of Fresh Hot Pepper Promotes Stress Resistance and Longevity in Caenorhabditis elegans

Piperine improves the health span of Drosophila melanogaster with age- and sex-specific effect

Piperine, a dietary phytochemical isolated from the Piper species, has been used as a natural medicine for pain, flu, and fever in ancient China and India. Although the health benefits of piperine have been widely studied, research on its effect on aging is limited. This study aimed to determine whether piperine has the potential to mitigate aging-related changes in the fruit fly (Drosophila melanogaster), which is an excellent model organism for studies on aging. The experiments were conducted using the newly eclosed or 30-day-old D. melanogaster wild-type strain Cantonized-white. Piperine was dissolved in 99% ethanol and added to the sucrose-yeast medium at a final concentration of 10, 35, 70, or 100 μM. The study examined the effects of piperine supplementation on the lifespan of D. melanogaster and other physiological functions, such as fecundity, feeding, lipid content, and resistance to environmental stress. Log-rank tests, Shapiro-Wilk test, F-test, t-test, or Wilcoxon rank sum test were used to analyze the data. Piperine failed to change the lifespan and body weight, but increased the fecundity and decreased the feeding rate in one-week-old flies. However, when piperine was fed to 30-day-old flies, it increased the lifespan of male flies and the fecundity and feeding rate of female flies. These results indicate that piperine can improve the health of aged flies. The findings suggest that piperine has age-dependent and sex-specific anti-aging effects in fruit flies.

Cinnamaldehyde Alleviates the Oxidative Stress of Caenorhabditis elegans in the Presence of Lactic Acid

Cinnamaldehyde is an excellent natural antioxidant with high antioxidant activity, but its function in food or human digestive tract under acidic conditions remains to be studied. The effects of cinnamaldehyde in the presence of lactic acid on oxidative stress of Caenorhabditis elegans and the underlying molecular mechanisms were investigated in the present study. Results showed that cinnamaldehyde with or without lactic acid exhibited good antioxidant ability, represented by high SOD and CAT activities in C. elegans, while lactic acid exerted no effect on the antioxidant enzymes. Trace elements, like Cu, Fe, or Se, are important for the activities of antioxidant enzymes. Data of metal elements analysis revealed that cinnamaldehyde made big differences on the levels of Mn, Cu, Se of worms compared with single lactic acid treatment. Moreover, mechanistic study suggested that in the presence of lactic acid, cinnamaldehyde could enhance the expressions of akt-2, age-1 to increase the antioxidant activities. In addition, we found that lactic acid was able to change the metabolic profile of cinnamaldehyde in C. elegans, characterized by nucleosides and amino acids, which were involved in the purine metabolism, the biosynthesis, and metabolism of some amino acids, etc. This study provides a theoretical basis for further revealing the functional activity and mechanism of cinnamaldehyde under acidic conditions.

Effect of Sodium Hyaluronate on Antioxidant and Anti-Ageing Activities in Caenorhabditis elegans

As an acidic polysaccharide, the formation of Hyaluronic acid (HA) is typically Sodium Hyaluronate (SH) for knee repair, oral treatment, skincare and as a food additive. Nevertheless, little information is available on the anti-ageing activity of SH as a food additive. Therefore, we treated C. elegans with SH, then inferred the anti-aging activity of SH by examining the lifespan physiological indicators and senescence-associated gene expression. Compared with the control group, SH (800 μg/mL) prolonged the C. elegans’ lifespans in regular, 35 °C and H2O2 environment by 0.27-fold, 0.25-fold and 1.17-fold. Simultaneously, glutathione peroxidase (GSH-Px), antioxidant enzyme superoxide dismutase (SOD) and catalase (CAT) were increased by 8.6%, 0.36% and 167%. However, lipofuscin accumulation, reactive oxygen species (ROS) and malondialdehyde (MDA) were decreased by 36%, 47.8–65.7% and 9.5–13.1%. After SH treatment, athletic ability was improved and no impairment of reproductive capacity was seen. In addition, SH inhibited the blocking effect of age-1 and up-regulated gene levels involving daf-16, sod-3, gst-4 and skn-1. In conclusion, SH provides potential applications in anti-ageing and anti-oxidation and regulates physiological function.

Water-Soluble Polysaccharides Extracted from Pueraria lobata Delay Aging of Caenorhabditis elegans under Heat Stress

Pueraria lobata is a perennial legume, commonly used as a food source in China. The polysaccharides extracted from P. lobata have demonstrated various biological activities. However their anti-aging effects and the underline mechanisms are largely unknown. In this study, water-soluble polysaccharides (WSPS) from P. lobata were extracted and demonstrated antioxidant activity against DPPH radicals and hydroxyl radicals in vitro. Using nematode Caenorhabditis elegans as a model, we found that WSPS remarkably prolonged the survival, increased growth and locomotion under heat stress. To investigate the possible mechanism, the levels of reactive oxygen species (ROS) and lipid peroxidation product malondialdehyde (MDA) were determined. WSPS significantly decreased ROS and MDA levels which is consistent with increased activity of superoxide dismutase (SOD). Meanwhile, WSPS upregulated the expression of stress resistance genes sod-1, sod-5, hsf-1, hsp-12.6, hsp-16.2, skn-1 and gst-4. Together, these results suggest that the anti-aging activity of WSPS under heat stress was mediated most likely by activation of the target genes of heat-shock transcription factor (HSF)-1 and skinhead (SKN)-1, and thus inducing endogenous ROS scavenging response.