Liquiritigenin Inhibits Lipid Accumulation in 3T3-L1 Cells via mTOR-Mediated Regulation of the Autophagy Mechanism

Targeting autophagy drug discovery: Targets, indications and development trends

Autophagy plays a vital role in sustaining cellular homeostasis and its alterations have been implicated in the etiology of many diseases. Drugs development targeting autophagy began decades ago and hundreds of agents were developed, some of which are licensed for the clinical usage. However, no existing intervention specifically aimed at modulating autophagy is available. The obstacles that prevent drug developments come from the complexity of the actual impact of autophagy regulators in disease scenarios. With the development and application of new technologies, several promising categories of compounds for autophagy-based therapy have emerged in recent years. In this paper, the autophagy-targeted drugs based on their targets at various hierarchical sites of the autophagic signaling network, e.g., the upstream and downstream of the autophagosome and the autophagic components with enzyme activities are reviewed and analyzed respectively, with special attention paid to those at preclinical or clinical trials. The drugs tailored to specific autophagy alone and combination with drugs/adjuvant therapies widely used in clinical for various diseases treatments are also emphasized. The emerging drug design and development targeting selective autophagy receptors (SARs) and their related proteins, which would be expected to arrest or reverse the progression of disease in various cancers, inflammation, neurodegeneration, and metabolic disorders, are critically reviewed. And the challenges and perspective in clinically developing autophagy-targeted drugs and possible combinations with other medicine are considered in the review.

Liquiritigenin Confers Liver Protection by Enhancing NRF2 Signaling through Both Canonical and Non-canonical Signaling Pathways

Oxidative stress plays a critical role in drug-induced liver injury. In recent years, liquiritigenin (LQ), a natural flavonoid distributed in Glycyrrhizae Radix et Rhizoma (Gan Cao), shows protective effects against oxidative hepatotoxicity. However, the underlying mechanism remains unclear. In this study, we mainly investigated the role of NRF2, a core transcription factor in oxidative stress, in LQ-induced hepatoprotection. Our results indicated that the function of LQ to eliminate reactive oxygen species in liver cells was dependent on NRF2 activation. Both a canonical signaling pathway and a non-canonical signaling pathway are involved in LQ-induced NRF2 activation. LQ induced NRF2 activation in a KEAP1-C151-dependent manner partially. Meanwhile, LQ led to the blockage of autophagic flux and upregulation of p62, which competitively bound with KEAP1 and conferred NRF2 activation in a KEAP1-C151-independent manner. Totally, our study reveals a novel molecular mechanism underlying the hepatoprotection of LQ, providing a new insight into the pathogenesis and therapeutic strategy of oxidative liver injury.

UPLC-QTOF-MS with a chemical profiling approach for holistic quality evaluation between a material reference of Wen Dan decoction and its commercial preparations

BACKGROUND

Wen Dan decoction (WDD) has been a famous classic formula for resolving phlegm since ancient times in China. Currently, there are many types of WDD commercial preparations produced through modern technology. However, it is not known whether the holistic quality of WDD commercial preparations is consistent with the traditional decocting method to exert its proper effects. Therefore, the WDD material reference was studied and prepared, which can represent the traditional Chinese formulation WDD.

METHODS

A method based on UPLC-QTOF-MS was developed to evaluate the quality of WDD material reference and commercial prescriptions. At the same time, the multivariate statistical method was used to compare the differences between the material reference and the commercial prescription by principal component analysis (PCA) and heatmap. Finally, the UPLC-QTOF-MS method was established to quantitatively study 11 representative components, including naringin, hesperidin, neohesperidin, liquiritin, glycyrrhizic acid, adenosine, liquiritigenin, tangeretin, eriocitrin, naringenin and synephrine.

RESULTS

A total of 107 compounds were identified in the WDD material reference by comparing the retention time and fragment ion characteristics, including 54 flavonoids, 14 triterpenes, 10 organic acids, 7 alkaloids, 7 coumarins and 15 other components. The samples were almost evenly split into two groups, indicating a difference in quality between the WDD material reference and its commercial preparations in multivariate statistical analysis. Eleven major components of linearity, precision, repeatability, stability and recovery rate met the requirements, which were clearly different in commercial preparations and WDD material references. In terms of the content of 11 components in the commercial preparation, only CP8 is close to the material reference, which is in agreement with the statistical analysis of the heatmap. The concentrations of naringin and neohesperidin from the WDD material reference were higher than those from the commercial preparations.

CONCLUSIONS

The quality evaluation method established in this study can be used to identify different sources of WDD but also proves that the WDD material reference contains higher naringin. Furthermore, this study confirmed that the preparation technology of WDD commercial prescriptions should be optimized on the basis of WDD material references, producing the closest possible clinical basis for the substance.

The Perspectives of Plant Natural Products for Mitigation of Obesity

Obesity is a metabolic disease caused by an imbalance between energy intake and consumption, which leads to excessive fat accumulation in adipose tissues [...].