(+)-Catechin (CE) is mainly found in green and black tea and has many biological effects, such as anti-inflammatory, anti-cancer, anti-viral effects, protecting human organs, especially the kidney. This study aims to identify the circRNAs induced by CE in db/db mice and their roles in diabetic nephropathy progression. After the db/db mice were treated with CE, RNA-seq was performed to identify the differentially expressed circRNA and mRNAs. The ceRNA regulatory network was constructed and analyzed using bioinformatics software and public databases (Cytoscape, ClueGO, MiRWalk, STRING, et al.). Our results revealed that 6 differentially expressed circRNAs are most associated with the cholinergic synapse, neurotrophin signaling pathway, and insulin signaling pathway. Among these, circRNA.5549 and circRNA.4712 might regulate Cd36, Cyp26b1, C8a, Cyp2j13, Grem2 genes through ceRNA regulatory mechanism in the presence of CE treatment. The expanded network of proteins interacting with these 5 genes shows that the TGF-β signaling pathway, signaling pathways regulating pluripotency of stem cell, fat digestion and absorption, and PPAR signaling pathway was highly enriched. Overall, circRNA.5549 and circRNA.4712 exhibit a promotive function in CE-treated db/db mice, especially in circRNA.5549/miR-29a-5P/Cd36 regulatory network, and this evidence suggest that their ceRNA regulatory network might be a therapeutic target for DN in humans.

This study established a method for the simultaneous determination of 74 pesticide residues in Panax notoginseng by QuEChERS pretreatment method coupled with GC-MS/MS, and carried out pesticide residue analysis on 20 batches of market samples in China. The samples were extracted with acetonitrile, cleaned up with primary secondary amine (PSA) and octadecylsilane (C₁₈) and determined by GC-MS/MS in multiple reaction monitoring (MRM) mode. Matrix-matched calibration was recommended to combat the matrix effect. A good linearity was observed in the range of 10−500 ng/mL with correlation coefficients ≥ 0.9950. The mean recoveries for most of the pesticides were in the range of 70%−120% with RSD < 20%. The limits of detection ranged 0.28–2.00 μg/kg, while the limits of quantification were 0.94–6.65 μg/kg. Following the application of "top-down" approach, the expanded measurement uncertainty for all the analytes was < 30%. The proposed method was successfully applied to determine pesticide residues in 20 market samples in China, where 9 pesticides were detected and quintozene exceeded the criteria domestically and abroad.