Metabonomic analysis of the therapeutic effect of exendin-4 for the treatment of tBHP-induced injury in mouse glomerulus mesangial cells

Innovative Application of Metabolomics on Bioactive Ingredients of Foods

Metabolomics, as a new omics technology, has been widely accepted by researchers and has shown great potential in the field of nutrition and health in recent years. This review briefly introduces the process of metabolomics analysis, including sample preparation and extraction, derivatization, separation and detection, and data processing. This paper focuses on the application of metabolomics in food-derived bioactive ingredients. For example, metabolomics techniques are used to analyze metabolites in food to find bioactive substances or new metabolites in food materials. Moreover, bioactive substances have been tested in vitro and in vivo, as well as in humans, to investigate the changes of metabolites and the underlying metabolic pathways, among which metabolomics is used to find potential biomarkers and targets. Metabolomics provides a new approach for the prevention and regulation of chronic diseases and the study of the underlying mechanisms. It also provides strong support for the development of functional food or drugs. Although metabolomics has some limitations such as low sensitivity, poor repeatability, and limited detection range, it is developing rapidly in general, and also in the field of nutrition and health. At the end of this paper, we put forward our own insights on the development prospects of metabolomics in the application of bioactive ingredients in food.

Liraglutide reduces oxidative stress and improves energy metabolism in methylglyoxal-induced SH-SY5Y cells

Diabetes mellitus can result in severe complications, such as neurodegenerative diseases including cognitive impairment and dementia. The glucagon-like peptide-1 (GLP-1) receptor agonist, liraglutide, is a novel antidiabetic drug with neuroprotective effects against neurodegenerative diseases. In this study, we explored the protective effect of liraglutide on SH-SY5Y cells exposed to methylglyoxal (MG), a byproduct of glucose metabolism that plays a key role in the development of diabetic encephalopathy. We found that liraglutide reduced the MG-induced oxidative stress, increased the activity of superoxide dismutase (SOD) and expression levels of P22phox, Gp91phox, and Xdh genes, and reduced reactive oxygen species (ROS) content. Metabolomics analysis based on ¹H nuclear magnetic resonance showed that liraglutide induced alterations in metabolites involved in energy metabolism，including promotion of gluconeogenesis. Moreover, we found that liraglutide promoted oxidative phosphorylation and inhibited glycolysis in SH-SY5Y cells. This study revealed that liraglutide improved diabetes-related neuropathy damage by reducing the level of oxidative stress and maintaining the balance of energy metabolism, thus offering new insights into the potential mechanism of liraglutide in neuronal protection.

Docosahexaenoic Acid Suppresses Oxidative Stress-Induced Autophagy and Cell Death via the AMPK-Dependent Signaling Pathway in Immortalized Fischer Rat Schwann Cells 1

Autophagy is the process by which intracellular components are degraded by lysosomes. It is also activated by oxidative stress; hence, autophagy is thought to be closely related to oxidative stress, one of the major causes of diabetic neuropathy. We previously reported that docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) induced antioxidant enzymes and protected Schwann cells from oxidative stress. However, the relationship between autophagy and oxidative stress-induced cell death in diabetic neuropathy has not been elucidated. Treatment with tert-butyl hydroperoxide (tBHP) decreased the cell survival rate, as measured by an MTT assay in immortalized Fischer rat Schwann cells 1 (IFRS1). A DHA pretreatment significantly prevented tBHP-induced cytotoxicity. tBHP increased autophagy, which was revealed by the ratio of the initiation markers, AMP-activated protein kinase, and UNC51-like kinase phosphorylation. Conversely, the DHA pretreatment suppressed excessive tBHP-induced autophagy signaling. Autophagosomes induced by tBHP in IFRS1 cells were decreased to control levels by the DHA pretreatment whereas autolysosomes were only partially decreased. These results suggest that DHA attenuated excessive autophagy induced by oxidative stress in Schwann cells and may be useful to prevent or reduce cell death in vitro. However, its potentiality to treat diabetic neuropathy must be validated in in vivo studies.