Gentiopicroside ameliorates glucose and lipid metabolism in T2DM via targeting FGFR1

The effect of Gougunao tea polysaccharide on lipid metabolism in hyperlipidemia induced by a high-fat diet and its structural characteristics

In this study, the effect of Gougunao tea polysaccharide (GTP40) on lipid metabolism in high-fat diet (HFD)-induced hyperlipidemic mice and its core structure were investigated. GTP40 effectively reversed the increase in weights of the liver and adipose tissues induced by HFD. The oxidative stress of the liver was also significantly alleviated following GTP40 intervention. According to the results of Real-Time quantitative Polymerase Chain Reaction (RT-qPCR), the genes associated with lipolysis were upregulated after GTP40 treatment, while lipogenesis-related genes were downregulated. Additionally, a homogeneous polysaccharide (GTP40-5P, obtained by degrading GTP40 for 5 h) with a molecular weight of 27858 Da was fractionated from GTP40 by the partial acid hydrolysis method. GTP40-5P was mainly composed of 62.30 ± 0.70 % neutral sugar, 54.82 ± 0.51 % uronic acid and 2.52 ± 0.74 % protein. The results of methylation and nuclear magnetic resonance (NMR) analysis indicated that the backbone of GTP40-5P was consisted of →4)-α-D-GalpA-(1 → 4)-β-D-Galp-(1→ units, with the terminal residue β-D-Galp-(1→ linked to →3,4)-α-D-GalpA-(1→ at the O-3 site, suggesting that it should be classified as homogalacturonan (HG)-type pectin with partial methyl esterification. These findings indicate that GTP40 alleviates lipid metabolism disorders in hyperlipidemic mice primarily via the AMPK signaling pathway. Furthermore, the elucidation of the primary structure of Gougunao tea polysaccharide enhances the understanding of the structure-activity relationship.

Active Constituent of HQS in T2DM Intervention: Efficacy and Mechanistic Insights

Traditional Chinese Medicine (TCM) is recognized for its complex composition and multiple therapeutic targets. Current pharmacological research often concentrates on extracts or individual components. The former approach faces numerous challenges, whereas the latter oversimplifies and disregards the synergistic effects of TCM components. This study aimed to address this limitation by evaluating the therapeutic efficacy and mechanisms of Huang-Qi San (HQS) active constituent (AC) against type 2 diabetes (T2DM). Active components of HQS were identified using network pharmacology and spectrum-effect correlation analysis. The reconstituted AC group was assessed both in vitro (for glucose consumption and glycogen synthesis) and in vivo (in T2DM mice), with metabolomics and molecular docking techniques used to elucidate the underlying mechanisms. Eight components exhibiting a correlation degree greater than 0.85 were identified as the representative components of HQS intervention for T2DM. These eight components were then mixed in equal proportions to produce AC. The AC group demonstrated increased glucose uptake and glycogen synthesis in vitro, surpassing both the HQS extract and individual components. In diabetic mice, AC significantly increased the insulin sensitivity, outperforming the HQS extract and matching the efficacy of metformin. Metabolomics analysis identified pentose and glucuronic acid interconversion as a critical metabolic pathway, with strong binding affinity (less than -15 kJ/mol) between AC and key enzymes. This research further substantiates the scientific validity and feasibility of emphasizing active constituents in the evaluation of TCM efficacy. Additionally, it provides a scientific foundation for the clinical application of HQS. Most importantly, this study serves as a demonstration of the development of new TCM drugs characterized by clear ingredients, safety, and effectiveness.

Gentiopicroside targeting AKT1 activates HIF-1α/VEGF axis promoting diabetic ulcer wound healing

Backgound

Gentiopicroside (GSP) have been proven to accelerate the healing of diabetic ulcers (DU), but the underlying molecular mechanisms remain unclear. This study aims to explore the mechanism by which GSP accelerates the healing of DU.

Method

The targets of GSP were firstly predicted using the SuperPred, SwissTargetPrediction, and Pharmmapper databases; DU-related transcriptome data were obtained from the GEO database, including GSE147890, GSE68183, and GSE199939; differential expression analysis was conducted using the Limma package, and DU-related targets were identified after summarization and de-duplication. Then, Potential targets for GSP treatment of DU were screened by Venn analysis; core targets for GSP treatment of DU were selected by constructing a protein-protein interaction (PPI) network; the mechanism of GSP treatment of DU was predicted by GO and KEGG enrichment analysis. Finally, the target binding of GSP to core targets was evaluated by molecular docking and CETSA assay, and in vitro experiments were conducted using L929 cells to validate the findings.

Result

A total of 538 targets of GSP and 10795 DU-related targets were predicted; Venn analysis identified 215 potential targets for GSP to accelerate DU wound healing; PPI network analysis suggested that AKT1 may be core targets for GSP treatment of DU; GO and KEGG enrichment analysis showed that pathways such as HIF-1 and VEGF are closely related to the treatment of DU with GSP, and it also participates in the regulation of various biological processes such as small molecule catabolism and leukocyte migration to exert its therapeutic effect on DU. Molecular docking and CETSA detection indicated that GSP can target bind to AKT1. The experimental results confirmed that GSP can significantly promote the proliferation and migration of L929 cells. Westen Blot results showed that GSP can accelerate DU wound healing via AKT1/HIF-1α/VEGF axis.

Conclusion

GSP target binding to AKT1 accelerates DU wound healing via the regulation of HIF-1α/VEGF axis.

Gut Microbiota in T2DM Patients with Microvascular Complications: A 16S rRNA Sequencing Study

Objective

This study aims to investigate the characteristics of gut microbiota in patients with microvascular complications of Type 2 Diabetes Mellitus (T2DM) using 16S rRNA high-throughput sequencing technology.

Methods

Patients diagnosed with T2DM were enrolled as study subjects. Based on the presence of microvascular complications, subjects were divided into a study group, a control group. Clinical fecal samples from the two groups were subjected to diversity analysis using the Illumina MiSeq high-throughput sequencing technology, comparing the richness and diversity of the gut microbiota between the two groups. The Tax4Fun software was utilized for the functional prediction of differential microbiota.

Results

A total of 3727 operational taxonomic units (OTUs) were identified, with 1311 OTUs common to both groups, and 1363 and 1053 OTUs unique to the study group and the control group, respectively. The study group exhibited a significant increase in the relative abundance of Clostridia and Negativicutes, and a marked decrease in Gammaproteobacteria, Bacilli, and Verrucomicrobia compared to the control group. LefSe analysis revealed significant differences in the relative abundance at two phyla, two classes, two orders, three families, and two genera levels between the groups. KEGG pathway analysis of differential microbiota identified 10 pathways with statistically significant differences (P<0.05).

Conclusion

This study reveals significant disparities in gut microbiota abundance between T2DM patients and those with microvascular complications of T2DM, suggesting potential microbial markers for diagnosing and treating microvascular complications of T2DM.

Novel sodium tauroursodeoxycholate-based multifunctional liposomal delivery system for encapsulation of oleanolic acid and combination therapy of type 2 diabetes mellitus

Liposomes have demonstrated great potential for drug delivery and diabetes treatment. However, hydrolysis by enzymes and emulsification by endogenous bile salts make liposomes unstable in the gastrointestinal tract. In this study, sodium tauroursodeoxycholate (TUDCNa)-based multifunctional bilosomes were designed to address the deficiencies of conventional liposomes. In the designed bilosomes, cholesterol was replaced by TUDCNa, which served as both a membrane stabilizer and an antidiabetic drug. Oleanolic acid (OA) was encapsulated in both conventional liposomes (OA-Ch-Lip) and bilosomes (OA-Tu-Bil) to compare their properties. Firstly, OA-Tu-Bil exhibited similar encapsulation efficiency and drug loading compared to OA-Ch-Lip, but with a smaller particle size. Secondly, OA-Tu-Bil showed better stability than OA-Ch-Lip. Thirdly, bilosomes exhibited prolonged intestinal retention time and improved permeability and oral bioavailability. Fourthly, in type 2 diabetes mellitus (T2DM) mice model, TUDCNa synergized with OA to exhibit the strongest therapeutic effect. In conclusion, TUDCNa have demonstrated the ability to substitute cholesterol in conventional liposomes, it provided a new approach for oral delivery of hypoglycemic drugs, and offered an innovative strategy for combination therapy.

Methionine restriction alleviates diabetes-associated cognitive impairment via activation of FGF21

Glucose metabolism disturbances may result in diabetes-associated cognitive decline (DACI). Methionine restriction (MR) diet has emerged as a potential dietary strategy for managing glucose homeostasis. However, the effects and underlying mechanisms of MR on DACI have not been fully elucidated. Here, we found that a 13-week MR (0.17 % methionine, w/w) intervention starting at 8 weeks of age improved peripheral insulin sensitivity in male db/db mice, a model for type 2 diabetes. Notably, MR significantly improved working as well as long-term memory in db/db mice, accompanied by increased PSD-95 level and reduced neuroinflammatory factors, malondialdehyde (MDA), and 8-hydroxy-2'-deoxyguanosine (8-OHdG). We speculate that this effect may be mediated by MR activating hepatic fibroblast growth factor 21 (FGF21) and the brain FGFR1/AMPK/GLUT4 signaling pathway to enhance brain glucose metabolism. To further delineate the mechanism, we used intracerebroventricular injection of adeno-associated virus to specifically knock down FGFR1 in the brain to verify the role of FGFR1 in MR-mediated DACI. It was found that the positive effects of MR on DACI were offset, reflected in decreased cognitive function, impaired synaptic plasticity, upregulated neuroinflammation, and balanced enzymes regulating reactive oxygen species (Sod1, Sod2, Nox4). Of note, the FGFR1/AMPK/GLUT4 signaling pathway and brain glucose metabolism were inhibited. In summary, our study demonstrated that MR increased peripheral insulin sensitivity, activated brain FGFR1/AMPK/GLUT4 signaling through FGF21, maintained normal glucose metabolism and redox balance in the brain, and thereby alleviated DACI. These results provide new insights into the effects of MR diet on cognitive dysfunction caused by impaired brain energy metabolism.