Chemical Composition Analysis of Highland Barley (Hordeum vulgare L.) with Different Modification Methods and Lipid...

In this study, the chemical composition of highland barley (HB), microwave fluidization HB (HB-1), extrusion and puffing HB (HB-2), and ultrafine pulverization HB (HB-3) were investigated based on untargeted metabolomics. In addition, RNA-seq transcriptomics, real-time polymerase chain reaction (qRT-PCR) and Western blot (WB) analysis were used to investigate the lipid metabolism mechanism of HB-1, induced by a high fat and cholesterol diet (HFCD). The results indicated that a total of 1292 metabolites were detected and classified into 78 distinct classes in the untargeted metabolomics analysis including fatty acyls, carboxylic acids and derivatives, glycerophospholipids, organooxygen compounds, prenol lipids, and so on. HB-1, HB-2, and HB-3 all increased the levels of amino acids and their derivatives, phenols, and carboxylic acid and its derivatives compared with HB. Furthermore, RNA-seq transcriptomic results indicated that HB-1 significantly modulated key genes of Cyp2c38, Cyp2b13, and Cyp2b9 related to steroid hormone biosynthesis and CD36, Plin4, and Fabp4 related to the PPAR signaling pathway, which played key roles in lipid metabolism. Moreover, qRT-PCR and WB results indicated that HB-1 obviously enhanced ADIPOQ expression level, while it reduced SCD-1, CD36, Fabp4, and SREBP-1c expression levels, suggesting that the alleviation of lipid metabolic dysregulation by HB-1 in hyperlipidemia mice might be mediated via participating in the PPARγ pathway. This study provided essential theoretical insights for the development and utilization of HB.