Comparison of Two Varieties Fig (Peggy Red and Green) Peel Extracts by Liquid Chromatography-Tandem Mass Spectrometry Analysis and for Neuroprotective Efficacy in Caenorhabditis elegans

Antioxidant and Neuroprotective Effects of Seed Oils from Trichosanthes kirilowii and T. laceribractea in Caenorhabditis elegans: A Comparative Analysis and Mechanism Study

Excess reactive oxygen species (ROS) can accelerate amyloid β (Aβ) aggregation and tau protein hyperphosphorylation in neuron cells, which further leads to neurodegenerative diseases such as Alzheimer's disease (AD). Therefore, there is an urgent need to find natural and safe antioxidants for preventing or treating such neurodegenerative diseases. The seeds of Trichosanthes kirilowii Maxim and T. laceribractea Hayata have long been used for medicinal and edible purposes in China. However, the antioxidant and neuroprotective activities and underlying mechanisms of their seed oils still remain unclear. Herein, we examine the antioxidant and neuroprotective effects of seed oils extracted from different germplasms, T. kirilowii (YNHH and SDJN) and T. laceribractea (ZJQT and SXHZ), on ROS levels and neuroprotective activities in C. elegans. The results demonstrated that the seed oils significantly reduced the ROS levels in C. elegans by 17.03-42.74%, with T. kirilowii (YNHH and SDJN) exhibiting significantly stronger ROS scavenging abilities than T. laceribractea (ZJQT and SXHZ). The seed oils from T. kirilowii (YNHH and SDJN) alleviated the production and aggregation of Aβ and the phosphorylation and polymerization of tau, suggesting a potential neuroprotective role. Conversely, seed oils from T. laceribractea (ZJQT and SXHZ) show minimal neuroprotective effects in C. elegans. These differential outcomes might stem from distinct mechanisms underlying antioxidant and neuroprotective effects, with the ctl-2 gene implicated as pivotal in mediating the significant neuroprotective effects of seed oils from T. kirilowii (YNHH and SDJN). Our findings have provided valuable insights into the antioxidant and neuroprotective properties of T. kirilowii seed oils, paving the way for further research aimed at elucidating the underlying mechanisms and exploring their potential therapeutic applications in combating neurodegenerative diseases.

Metabolic Regulations of Smilax china L. against β-Amyloid Toxicity in Caenorhabditis elegans

Smilax china L. (Chinaroot) is a natural herb that has multiple uses, such as being used to make tea and food. Both its roots and leaves have different uses due to their unique components. In this study, we analyzed the extract of S. china. roots using LC-HRMS and evaluated the neuroprotective effects and metabolic regulation of S. china on Caenorhabditis elegans. Chinaroot extract prolonged the life span of healthy nematodes, delayed the paralysis time of transgenic CL4176, and reduced the level of β-amyloid deposition in transgenic CL2006. The comprehensive analysis of metabolomics and qRT-PCR revealed that Chinaroot extract exerted neuroprotective effects through the valine, leucine and isoleucine degradation and fatty acid degradation pathways. Moreover, we first discovered that the expressions of T09B4.8, ech-7, and agxt-1 were linked to the neuroprotective effects of Chinaroot. The material exerted neuroprotective effects by modulating metabolic abnormalities in AD model C. elegans. Our study provides a new foundation for the development of functional food properties and functions.