Gentiopicroside alleviates cardiac inflammation and fibrosis in T2DM rats through targeting Smad3 phosphorylation.

BACKGROUND: Cardiac fibrosis is a major structural change observed in the heart of patients with type 2 diabetes mellitus (T2DM), ultimately resulting in heart failure (HF). Suppression of inflammation is an effective therapeutic strategy for treating cardiac fibrosis and HF. Gentiopicroside (GPS), the primary component of Gentiana manshurica Kitagawa, possess potent anti-inflammatory activity. However, its cardioprotective role remains elusive. PURPOSE: We explored the potential cardioprotective role of GPS in T2DM rats and its underlying mechanisms. METHODS: T2DM rats built by high-fat diet and streptozotocin were orally administered 25, 50, or 100 mg/kg GPS, daily for 8 weeks. The positive control drug was Metformin (200 mg/kg/day). Primary cardiac fibroblasts (CFs) were induced by high glucose (30 mM) and subsequently treated with GPS (100 µM). Cardiac function and pathological changes were analyzed using echocardiography and histological staining. Potential targets of GPS were predicted using Molecular docking. Real-time PCR as well as western blotting were applied to verify the expression of objective genes. RESULTS: All three doses reduced fasting blood glucose levels, but only 50 and 100 mg/kg GPS improved cardiac function and alleviated inflammation and fibrosis in T2DM rats. GPS (100 mg/kg) exhibited a better effect, similar to that of metformin. Mechanistically, binding between GPS and the MH2 domain of Smad3 blocked high glucose-induced Smad3 phosphorylation, thus attenuating inflammation, oxidative stress, and activation in CFs. CONCLUSION: We, for the first time, demonstrated that GPS improved cardiac function in T2DM rats and elucidated the underlying mechanism through which GPS targeted Smad3 phosphorylation to suppress inflammation and activation in CFs, thereby revealing the potential application of GPS in HF therapy.

Heterogeneous microenvironment analysis to explore the potential regulatory role of endothelial-mesenchymal transition in idiopathic pulmonary fibrosis.

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive interstitial lung disease mainly caused by excessive proliferation of fibroblasts and activation of myofibroblasts. The cellular microenvironment is mainly composed of different types of cellular components and extracellular matrix (ECM), whose changes directly affect cellular heterogeneity, resulting in immensely complex cellular interactions. However, microenvironment study is mainly focused on the pathological process of tumors, and the microenvironment changes during IPF development remain unclear. Methods: The current study intends to employ IPF-related single-cell sequencing and gene expression profile data to analyze the scores of different cell clusters in the IPF microenvironment, and exploit the underlying interaction between cells to illustrate the fundamental mechanism causing IPF. Results: Our analysis revealed that the amount of endothelial cells was obviously decreased, and the amount of fibroblasts and myofibroblasts was increased during the development of IPF, suggesting a possible endothelial-mesenchymal transition (EndMT) process. Furthermore, we found that the hub genes obtained through IPF-related gene expression profile analysis may play a regulative role in the number and function of endothelial cells and fibroblasts/myofibroblasts during IPF. Conclusions: Our research represents a valuable analysis of the cellular microenvironment, and provides a novel mechanistic insight into the pathobiology of not only EndMT in IPF, but also other traumatic fibrotic disease disorders.