Iridin Research Articles

Iridin Prevented Against Lipopolysaccharide-Induced Inflammatory Responses of Macrophages via Inactivation of PKM2-Mediated Glycolytic Pathways.

PurposeAbnormal glycolysis of immune cells contributed to the development of inflammatory response. Inhibition of this Warburg phenotype could be a promising strategy for preventing various inflammatory diseases. Iridin (IRD) is a natural isoflavone, and exerts anticancer, antioxidant, and anti-inflammatory effects. However, the underlying mechanism of IRD on acute inflammation remains unknown. In this study, the protective effects of IRD against lipopolysaccharide (LPS)-induced inflammation were investigated in murine macrophage RAW264.7 cells and in mice.MethodsThe inhibition of IRD on NO production in culture medium was detected by Griess assay while the levels of TNF-α, IL-1β, and MCP-1 were detected by ELISA assay. The effects of IRD on OCR and ECAR levels in LPS-treated macrophages were monitored by using Seahorse Analyzer. The apoptosis rate as well as the release of ROS and NO of RAW264.7 cells were analyzed by flow cytometric assay. The protective effects of IRD were investigated on LPS-induced inflammation in mice. The expressions of PKM2 and its downstream (p-JAK1, p-STAT1, p-STAT3, p-p65, iNOS, and COX2) in cells and in lung tissues were detected by Western blotting analysis.ResultsIRD treatment at the concentrations of 12.5–50 μM significantly inhibited the productions of TNF-α, IL-1β, MCP-1, and ROS, and suppressed the levels of glucose uptake and lactic acid in LPS-treated RAW264.7 cells. Oral administration with IRD (20–80 mg/kg) inhibited LPS-induced acute lung injury as well as inflammatory cytokine production in mice. Moreover, IRD targeted pyruvate kinase isozyme type M2 (PKM2) and suppressed its downstream p-JAK1, p-STAT1, p-STAT3, p-p65, iNOS, and COX2, which could be abolished by PKM2 agonist DASA-58 and antioxidant N-acetyl-L-cysteine, but partly be reversed by NF-κB activator CUT129 and JAK1 activator RO8191.ConclusionIRD alleviated LPS-induced inflammation through suppressing PKM2-mediated pathways, and could be a potential candidate for the prevention of inflammatory diseases.

A biochemical & biophysical study on in-vitro anti-glycating potential of iridin against d-Ribose modified BSA

Non-enzymatic protein glycation results in the formation of advanced glycation end products (AGEs) leads to the pathogenesis of long-term diabetic complications. Iridin (ID), an antioxidant, plays an important role in protecting against oxidative stress and could therefore be an efficacious anti-glycating regimen. Herein, we assessed the anti-glycating potential of ID against d-ribose induced glycation of bovine serum albumin (BSA) by various biophysical and biochemical techniques. Our results from several physicochemical assays advocated that ID was able to evidently prevent the AGEs generation via reducing hyperchromicity, early glycation products (EGPs), carbonyl content (CC), hydroxymethyl furfural (HMF) content, production of fluorescent AGEs, protection against loss of secondary structure (i.e. α-helix and β-sheets) of proteins, increasing the free lysine and free arginine content, reduced binding of congo red (CR), and reduced thioflavin T (ThT) and 8-aninilo-1-napthalene sulphonate (ANS)-specific fuorescence in glycated-BSA (Gly-BSA). On the basis of these findings, we concluded that ID possesses the significant anti-glycation potential and may be established as a remarkable anti-AGEs therapeutic agent. Further in-vivo and clinical studies are still warranted to uncover the therapeutic effects of ID against age-related as well as metabolic diseases.

A novel strategy to evaluate the quality of herbal products based on the chemical profiling, efficacy evaluation and pharmacokinetics

The purpose of this study was to establish a chemical profiling method to compare the chemical composition of herbal products by using extracts of Belamcandae Rhizoma(EBR) extracted with different polarity solvent as an example, and evaluate the quality of EBR based on the analysis of chemical profiling, efficacy evaluation and pharmacokinetics. As seen from the results of chemical profiling, the PCA and PLS-DA score plot indicated that the dots of Belamcandae Rhizoma water extracts were separated from ethanol extracts obviously, which suggested significant differences of chemical profiling existing in the different solvent extracts. The PCA and PLS-DA loading plot illustrated that the main compounds contributing to chemical profiling differences were tectoridin(TD), iristectorin B(IT B), iridin(ID), tectorigenin(TG), irigenin(IG), iristectorigein A(IG A), dichotomitin(DT) and irisflorentin(IF). Furthermore, the results of HPLC analysis demonstrated that the contents of these main compounds in ethanol extracts were significantly higher than that in water extracts (P < 0.01). Both the pharmacological and hematoxylin-eosin staining studies indicated that the ethanol extracts of Belamcandae Rhizoma had a better therapeutic effect than water extracts in oral ulcer model rats (P<0.01). It is suggested that the ethanol extracts were beneficial to the absorption and bioavailability of TG which was one of the most important bioactive compounds of Belamcandae Rhizoma in pharmacokinetic study in rats. This work provided a novel method to optimize the extraction process of EBR and related herbal products. Compared with the conventional chemical fingerprint methodology, the approach proposed above is not only a powerful tool to identify efficacy-related components for the quality evaluation, but also can be used to predict the therapeutic efficacy of herbal products.