Protective effect of cynaroside on sepsis-induced multiple organ injury through Nrf2/HO-1-dependent macrophage polarization.

Cynaroside is the primary flavonoid component of honeysuckle which has been widely used as Chinese traditional medicine given its anti-inflammation properties. Overactive systemic inflammatory response and multi-organ injury are the leading causes of life-threatening sepsis. Regulation of macrophage polarization balance may act as a promising strategy for its treatment. In the present study, we aimed to investigate whether cynaroside exerted protective effects against sepsis and its potential mechanism. Building upon a sepsis mouse model, we observed cynaroside alleviated serum levels of inflammatory factors including IL-1ß and TNF-α at 5 and 10 mg/kg. The pathological injury of heart, kidney and lung was remarkedly attenuated as the levels of blood urea nitrogen, creatinine, creatine kinase-MB and lactate dehydrogenase were reduced nearly 2.8-, 2.7-, 2.4-, and 2.5-fold as compared with the sepsis mice, respectively. We further demonstrated cynaroside suppressed the biomarker of pro-inflammatory macrophage M1 phenotype (iNOS+) and promotes the anti-inflammatory M2 polarization (CD206+) in the injury organs of septic mice. Mechanistic research verified cynaroside inhibited LPS-induced polarization of macrophage into M1 phenotype, which can be highly blocked by Nrf2 inhibitor. Expectedly, Nrf2 and its downstream (Heme oxygenase-1 (HO-1)) was upregulated in injury organs after treating with cynaroside, indicating the involvement of Nrf2 signaling. Taken together, the data claims cynaroside ameliorated systematic inflammation and multi-organ injury dependent on Nrf2/HO-1 pathway in septic mice.

Cynaroside prevents macrophage polarization into pro-inflammatory phenotype and alleviates cecal ligation and puncture-induced liver injury by targeting PKM2/HIF-1α axis.

The treatment of sepsis is still challenging and the liver is an important target of sepsis-related injury. Macrophages are important innate immune cells in liver, and modulation of macrophages M1/M2 polarization may be a promising strategy for septic liver injury treatment. Macrophage polarization and inflammation of liver tissue has been shown regulated by pyruvate kinase M2 (PKM2)-mediated aerobic glycolysis and immune inflammatory pathways. Therefore, modulating PKM2-mediated immunometabolic reprogramming presents a novel strategy for inflammation-associated diseases. In this study, cynaroside, a flavonoid compound, promoted macrophage phenotypic transition from pro-inflammatory M1 to anti-inflammatory M2, and mitigated sepsis-associated liver inflammatory damage. We established that cynaroside reduced binding of PKM2 to hypoxia-inducible factor-1α (HIF-1α) by abolishing translocation of PKM2 to the nucleus and promoting PKM2 tetramer formation, as well as suppressing phosphorylation of PKM2 at Y105 in vivo and in vitro. Moreover, cynaroside restored pyruvate kinase activity, inhibited glycolysis-related proteins including PFKFB3, HK2 and HIF-1α, and inhibited glycolysis-related hyperacetylation of HMGB1 in septic liver. Therefore, this study reports a novel function of cynaroside in hepatic macrophage polarization, and cecum ligation and puncture-induced liver injury in septic mice. The findings provide crucial information with regard to therapeutic efficacy of cynaroside in the treatment of sepsis.

Carpesium abrotanoides (L.) Root as a Potential Source of Natural Anticancer Compounds: Targeting Glucose Metabolism and PKM2/HIF-1α Axis of Breast Cancer Cells.

Carpesium abrotanoides L. (CA) is widely used as a medicinal plant in Asia. The biological activities of the extract from the roots of Carpesium abrotanoides L. (PCA) and its major components were analyzed in this study. PCA was separated and identified with mass spectrometry. Furthermore, we sought to elucidate the anticancer activity of PCA and its mechanisms. PCA exerted its anti-breast cancer activity through inhibiting the expression of glycolysis-related genes, such as glucose transporter 1, lactate dehydrogenase A, and hexokinase 2. Moreover, PCA downregulated the expression of pyruvate kinase M2 and altered its cellular translocation. We also demonstrated PCA is an inhibitor of the PKM2/hypoxia-inducible factor-1α axis, indicating that PCA is potentially useful as an anti-breast cancer agent. PRACTICAL APPLICATION: In this study, the extract from roots of Carpesium abrotanoides Linn. (PCA) was shown to have a noticeable anticancer effect against breast cancer in vitro, and PCA exerts the anticancer activity by regulating glucose metabolism and PKM2 expression. These findings indicate that PCA is a promising agent with practical applications in the development of functional food containing Carpesium abrotanoides L. root extracts.