Magnolol, a compound extracted from Magnolia officinalis, demonstrates potential efficacy in addressing metabolic dysfunction and cardiovascular diseases. Its biological activities encompass anti-inflammatory, antioxidant, anticoagulant, and anti-diabetic effects. Growth/differentiation factor-15 (GDF-15), a member of the transforming growth factor β superfamily, is considered a potential therapeutic target for metabolic disorders. This study investigated the impact of magnolol on GDF-15 production and its underlying mechanism. The research examined the pharmacological effect of magnolol on GDF-15 expression in vitro and in vivo, and determined the involvement of endoplasmic reticulum (ER) stress signaling in this process. Luciferase reporter assays, chromatin immunoprecipitation, and in vitro DNA binding assays were employed to examine the regulation of GDF-15 by activating transcription factor 4 (ATF4), CCAAT enhancer binding protein γ (CEBPG), and CCCTC-binding factor (CTCF). The study also investigated the effect of magnolol and ATF4 on the activity of a putative enhancer located in the intron of the GDF-15 gene, as well as the influence of single nucleotide polymorphisms (SNPs) on magnolol and ATF4-induced transcription activity. Results demonstrated that magnolol triggers GDF-15 production in endothelial cells (ECs), hepatoma cell line G2 (HepG2) and hepatoma cell line 3B (Hep3B) cell lines, and primary mouse hepatocytes. The cooperative binding of ATF4 and CEBPG upstream of the GDF-15 gene or the E1944285 enhancer located in the intron led to full-power transcription of the GDF-15 gene. SNP alleles were found to impact the magnolol and ATF4-induced transcription activity of GDF-15. In high-fat diet ApoE^-/- mice, administration of magnolol induced GDF-15 production and partially suppressed appetite through GDF-15. These findings suggest that magnolol regulates GDF-15 expression through priming of promoter and enhancer activity, indicating its potential as a drug for the treatment of metabolic disorders.
Lignans/pharmacology* ; Growth Differentiation Factor 15/metabolism* ; Animals ; Biphenyl Compounds/pharmacology* ; Endoplasmic Reticulum Stress/drug effects* ; Activating Transcription Factor 4/genetics* ; Mice ; Humans ; Male ; Magnolia/chemistry* ; CCAAT-Enhancer-Binding Proteins/genetics* ; Mice, Inbred C57BL

Objective: To evaluate the effect of the "Interner Plus-based AIDS Comprehensive Prevention Service System" among MSM in Guangzhou, during 2010-2017, using a dynamic compartmental model. Methods: A dynamic compartmental model was developed to describe the HIV situation among MSM in Guangzhou. This model was parameterized on data from published literature or surveillance programs from the Guangzhou CDC. The Matlab 7.0 software was used for coding and analysis on collected data. HIV prevalence was analyzed among MSM under the status quo data and estimated the impact by the "Internet Plus" AIDS prevention services project. Results: HIV prevalence would have increased to 22.75% in 2017, and the total number of new HIV infections would have been 11 038, from 2010 to 2017, using the data status quo. Under the Guangzhou "Internet Plus" AIDS prevention services project, the prevalence of HIV among MSM from 2010 to 2017 was estimated to be 8.44%, 9.68%, 10.65%, 11.34%, 11.73%, 11.83%, 11.71% and 11.43% in Guangzhou, which were similar to the surveillance data. The total number of new infections in the past 8 years under the "Internet Plus" scenario was estimated to be 4 009. The "Internet Plus" program would have prevented 7 029 (63.68%) new infections during 2010-2017 as compared to the number, status quo. Conclusions The fitting result of dynamic compartmental model seemed more reasonable, which was applicable to predict HIV epidemic among MSM in Guangzhou, suggesting that the increase of HIV prevalence had been curbed since the "Internet Plus" project which was launched in 2010, and the "Interner Plus-based AIDS Comprehensive Prevention Service System" had achieved the purpose as planned, epidemiologically.