Celastrol targets the ChREBP-TXNIP axis to ameliorates type 2 diabetes mellitus.

BACKGROUNDS: Thioredoxin-interacting protein (TXNIP) plays a pivotal role in regulation of blood glucose homeostasis and is an emerging therapeutic target in diabetes and its complications. Celastrol, a pentacyclic triterpene extracted from the roots of Tripterygium wilfordii Hook F, can reduce insulin resistance and improve diabetic complications. PURPOSE: This study aimed to untangle the mechanism of celastrol in ameliorating type 2 diabetes (T2DM) and evaluate its potential benefits as an anti-diabetic agent. METHODS: db/db mice was used to evaluate the hypoglycemic effect of celastrol in vivo; Enzyme-linked immunosorbent assay (ELISA) and 2-NBDG assay were used to detect the effect of celastrol on insulin secretion and glucose uptake in cells; Western blotting, quantitative reverse transcription PCR (RT-qPCR) and immunohistological staining were used to examine effect of celastrol on the expression of TXNIP and the carbohydrate response element-binding protein (ChREBP). Molecular docking, cellular thermal shift assay (CETSA), drug affinity responsive targets stability assay (DARTS) and mass spectrometry were used to test the direct binding between celastrol and ChREBP. Loss- and gain-of-function studies further confirmed the role of ChREBP and TXNIP in celastrol-mediated amelioration of T2DM. RESULTS: Celastrol treatment significantly reduced blood glucose level, body weight and food intake, and improved glucose tolerance in db/db mice. Moreover, celastrol promoted insulin secretion and improved glucose homeostasis. Mechanistically, celastrol directly bound to ChREBP, a primary transcriptional factor upregulating TXNIP expression. By binding to ChREBP, celastrol inhibited its nuclear translocation and promoted its proteasomal degradation, thereby repressing TXNIP transcription and ultimately ameliorating T2DM through breaking the vicious cycle of hyperglycemia deterioration and TXNIP overexpression. CONCLUSION: Celastrol ameliorates T2DM through targeting ChREBP-TXNIP aix. Our study identified ChREBP as a new direct molecular target of celastrol and revealed a novel mechanism for celastrol-mediated amelioration of T2DM, which provides experimental evidence for its possible use in the treatment of T2DM and new insight into diabetes drug development for targeting TXNIP.

Qihu Preparation Ameliorates Diabetes by Activating the AMPK Signaling Pathway in db/db Mice.

PURPOSE: To examine the pharmacological effects of Qihu on type 2 diabetes mellitus using db/db mice. MATERIALS AND METHODS: Thirty-seven db/db mice were randomly divided into the following 5 groups: diabetes model control group (DM group; n = 7), administered with the adjuvant 0.3% carboxymethyl cellulose-Na; positive control group (Met group; n = 8), administered with metformin (0.13 g/kg bodyweight); Qihu-L group (n = 7), administered with a low dose of Qihu (0.75 g/kg bodyweight), Qihu-M group (n = 7), administered with a medium dose of Qihu (1.5 g/kg bodyweight); Qihu-H group (n = 8), administered with a high dose of Qihu (3.0 g/kg bodyweight). BKS mice (n = 8) were used as the negative control group. The db/db mice were administered with drugs through oral gavage for 28 days. The random blood glucose levels, glucose tolerance test, bodyweight, food intake, and blood lipid levels of the mice were measured during the experimental period. The liver and pancreas tissues were collected for pathological, quantitative real-time polymerase chain reaction, and Western blotting analyses. RESULTS: Compared with the DM group, the Qihu groups exhibited decreased bodyweight gain. The blood glucose levels in the Qihu-L, Qihu-M, and Qihu-H were 31.46%, 43.73%, and 51.83%, respectively, lower than those in the DM group. The triglyceride levels were significantly downregulated and the swelling and steatosis of the hepatocytes were significantly lower in the Qihu-M and Qihu-H groups than in the DM group. Qihu downregulated the expression of IL-1ß, IL-6, and TXNIP and upregulated the AMP-activated protein kinase (AMPK) signaling pathway in the pancreas and liver tissues of db/db mice. CONCLUSION: The anti-diabetic effects of Qihu are mediated through the activation of the AMPK/Txnip signaling and the downregulation of the secretion of inflammatory factors in db/db mice.

YY1-mediated up-regulation of lncRNA LINC00466 facilitates glioma progression via miR-508/CHEK1.

BACKGROUND: The abnormal expression of lncRNA LINC00466 (LINC00466) has been demonstrated in several tumor types. However, the expression pattern and functions of LINC00466 in glioma remain uninvestigated. METHODS: A reverse transcriptase-polymerase chain reaction (RT-PCR) was utilized to analyze LINC00466 in human glioma tissues and cell lines. Luciferase reporter assays were performed to explore whether YY1 could bind to the promoter region of LINC00466. Cell counting kit-8, flow cytometry, colony-formation, transwell migration and invasion assays were carried out to determine the involvement of INC00466 in glioma. Luciferase assays and pulldown assays were conducted to verify the binding sites. RESULTS: We report that LINC00466 expression is increased in glioma cells and tissues. YY1 transcription factor (YY1) can bind directly to the LINC00466 promoter region. Clinical studies revealed that the elevated expression of LINC00466 is closely correlated with an advanced World Health Organization grade (p = 0.008), Karnofsky Performance Status score (p = 0.004) and a short overall survival (p = 0.0035) of glioma patients. Functional assays revealed that LINC00466 knockdown distinctly suppresses glioma cell proliferation, migration, invasion and epithelial-mesenchymal progress, and also promotes apoptosis. Moreover, dual-luciferase reporter assays indicated that LINC00466 acts as an endogenous sponge via binding to miR-508 and decreasing its expression. Luciferase assays and RT-PCR assays demonstrated that checkpoint kinase 1 (CHEK1) is a target of miR-508, and LINC00466 modulates CHEK1 levels by competing for miR-508. LINC00466 may exhibit its anti-oncogenic roles through targeting the miR-508/CHEK1 axis. CONCLUSIONS: Our findings identified a novel glioma-related long non-coding RNA, LINC00466, which may provide a potential novel prognostic and therapeutic target for glioma.

Enhancing and Complementary Mechanisms of Synergistic Action of Acori Tatarinowii Rhizoma and Codonopsis Radix for Alzheimer's Disease Based on Systems Pharmacology.

MATERIALS AND METHODS: In this study, a systems pharmacology-based strategy was used to elucidate the synergistic mechanism of Acori Tatarinowii Rhizoma and Codonopsis Radix for the treatment of AD. This novel systems pharmacology model consisted of component information, pharmacokinetic analysis, and pharmacological data. Additionally, the related pathways were compressed using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, and the organ distributions were determined in the BioGPS bank. RESULTS: Sixty-eight active ingredients with suitable pharmacokinetic profiles and biological activities were selected through ADME screening in silico. Based on 62 AD-related targets, such as APP, CHRM1, and PTGS1, systematic analysis showed that these two herbs were mainly involved in the PI3K-Akt signaling pathway, MAPK signaling pathway, neuroactive ligand-receptor interaction, and fluid shear stress and atherosclerosis, indicating that they had a synergistic effect on AD. However, ATR acted on the KDR gene, while CR acted on IGF1R, MET, IL1B, and CHUK, showing that they also had complementary effects on AD. The ingredient contribution score involved 29 ingredients contributing 90.14% of the total contribution score of this formula for AD treatment, which emphasized that the effective therapeutic effects of these herbs for AD were derived from both ATR and CR, not a single herb. Organ distribution showed that the targets of the active ingredients were mainly located in the whole blood, the brain, and the muscle, which are associated with AD. CONCLUSIONS: In sum, our findings suggest that the systems pharmacology methods successfully revealed the synergistic and complementary mechanisms of ATR and CR for the treatment of AD.