Activation of PPARγ is required for hydroxysafflor yellow A of Carthamus tinctorius to attenuate hepatic fibrosis induced by oxidative stress.
Oxidative stress caused hepatic fibrosis by activating hepatic stellate cells (HSCs), which were implemented by depressing PPARγ activation. Hydroxysafflor yellow A (HSYA) as a nature active ingredient with antioxidant capacity was able to effectively attenuate oxidative stress mediated injury. So it will be very interesting to study effect of HSYA on HSCs activation and liver fibrosis, and reveal the role of PPARγ·CCl4 and H2O2 were used to mimic oxidative stress mediated hepatic injury in vitro and in vivo respectively. The anti-fibrosis effects of HSYA were evaluated and its mechanisms were disclosed by applying western blot, histopathological analysis, flow cytometry, RT-PCR and ELISA. Our results showed that HSCs activation and proliferation could be induced by oxidative stress, and the expressive levels of TGF-β1 and TIMP-1, the serum levels of ALT, AST, HA, LN, III-C and IV-C were also enhanced by oxidative stress, which is correlated with liver fibrosis (p<0.05 or p<0.01). HSYA was able to effectively inhibit oxidative stress mediated hepatic injury by increasing the activities of antioxidant enzymes, up regulating the expression of PPARγ and MMP-2, and down regulating the expression of TGF-β1 and TIMP-1, and reducing α-SMA level. The protective effect of HSYA can be significantly attenuated by GW9662 via blocking PPARγ (p<0.05 or p<0.01). Taken together, these results demonstrate that HSYA is able to significantly protect the liver from oxidative stress, which requires for HSYA to stimulate PPARγ activity, reduce cell proliferation and suppress ECM synthesis.
Wang CY
,Liu Q
,Huang QX
,Liu JT
,He YH
,Lu JJ
,Bai XY
... -
《-》
Hydroxysafflor yellow A protects against chronic carbon tetrachloride-induced liver fibrosis.
Hydroxysafflor yellow A (HSYA) was isolated from the dried flower of Carthamus tinctorius L. which was extensively used in traditional Chinese medicine to treat cirrhosis. However, the potential protective effect of HSYA in liver fibrosis is still unknown. In the present study, we investigated the effects of HSYA in rats with carbon tetrachloride (CCl4)-induced liver fibrosis. Sprague-Dawley (SD) rats were subjected to biweekly CCl4 injections over 12 weeks, while controls were given isovolumetric injections of olive oil. HSYA was given in a daily dose of 5 mg/kg by means of intraperitoneal concurrent with CCl4. Hepatic fibrosis was quantified by digital analysis of Masson's trichrome stained slides and hydroxyproline content. mRNA expression was quantified by real-time polymerase chain reaction (PCR), and protein was quantified by western blot or enzyme-linked immunosorbent assay (ELISA). CCl4 treatment induced micronodular liver fibrosis with a pronounced deposition of collagen fibers. HSYA significantly reduced liver fibrosis. HSYA down regulates α-smooth muscle actin (SMA), collagen α type I, matrix metalloproteinases (MMP)-9, and tissue inhibitors of metalloproteinases (TIMP)-1 gene expression. This was accompanied by a decreased expression of transforming growth factor (TGF)-β1 and phosphorylation of Smad4. These results indicate that HSYA might be a promising antifibrotic agent in chronic liver disease.
Zhang Y
,Guo J
,Dong H
,Zhao X
,Zhou L
,Li X
,Liu J
,Niu Y
... -
《-》
Hydroxysafflor yellow A exerts anti-fibrotic and anti-angiogenic effects through miR-29a-3p/PDGFRB axis in liver fibrosis.
Liver fibrosis is a prevalent pathological process in chronic liver diseases characterized by excessive extracellular matrix (ECM) deposition and abnormal angiogenesis. Notably, hepatic stellate cells (HSCs) are the primary source of ECM. Activated HSCs not only secrete numerous pro-fibrotic cytokines but also are endowed with a pro-angiogenic phenotype to promote pathological angiogenesis. Therefore, targeted modulation of HSCs has emerged as a pivotal strategy for addressing liver fibrosis. Hydroxysafflor yellow A (HSYA) is a homology of medicine and food colourant with good pharmacological activity. However, the precise mechanisms of HSYA against liver fibrosis remain unclear.
The objective of this study was to elucidate the impact of HSYA on liver fibrosis and pathological angiogenesis, as well as the underlying mechanisms in vitro and in vivo studies.
The efficacy and mechanisms of HSYA on TGF-β1-induced HSCs and VEGFA-induced endothelial cells were investigated by MTT assay, EdU cell proliferation assay, cell scratch assay, Elisa assay, immunofluorescence assay, molecular docking, cell transfection assay, western blot analysis and RT-qPCR analysis. In CCl4-induced liver fibrosis mice model, H&E, Masson, and Sirius red staining were used to observe histopathology. Serum transaminase activity and liver biochemical indexes were tested by biochemical kit. Immunohistochemical, fluorescence in situ hybridization (FISH), western blot analysis and RT-qPCR analysis were implemented to determine the mechanism of HSYA in vivo.
Herein, our findings confirmed that HSYA inhibited the proliferation, migration and activation of HSCs, as evidenced by a reduction in cell viability, relative migration rate, EdU staining intensity, and pro-fibrotic mRNAs and proteins expression in vitro. Mechanistically, HSYA played an anti-fibrotic and anti-angiogenic role by partially silencing PDGFRB in activated HSCs, thereby disrupting PDGFRB/MEK/ERK signal transduction and inhibiting the expression of HIF-1α, VEGFA and VEGFR2 proteins. Importantly, PDGFRB was a target gene of miR-29a-3p. Treatment with HSYA reversed the down-regulation of miR-29a-3p and antagonized PDGFRB signaling pathway in TGF-β1-induced HSCs transfected with miR-29a-3p inhibitor. Consistent with our in vitro study, HSYA exhibited a good hepatoprotective effect in CCl4-induced liver fibrosis mice by reducing serum ALT and AST levels, decreasing the contents of four fibrosis indicators (HA, PIIIP, ColIV and LN) and hydroxyproline, and inhibiting the TGF-β1/TGFBR signaling pathway. In terms of mechanisms, HSYA alleviated pathological angiogenesis in fibrotic liver by deactivating PDGFRB signaling pathway and impairing the positive expression of CD31. Subsequently, FISH results further corroborated HSYA affected the activation of HSCs and angiogenesis achieved by the concurrent upregulation of miR-29a-3p and downregulation of α-SMA and VEGFA. Additionally, treatment with HSYA also forged a link between HSCs and endothelial cells, as supported by inhibiting the aberrant proliferation of endothelial cells.
Fundamentally, the current study has illustrated that HSYA ameliorates liver fibrosis by repressing HSCs-mediated pro-fibrotic and pro-angiogenic processes, which is contingent upon the regulatory effect of HSYA on the miR-29a-3p/PDGFRB axis. These findings provide compelling evidence bolstering the potential of HSYA as a therapeutic agent in liver fibrosis.
Xue X
,Li Y
,Zhang S
,Yao Y
,Peng C
,Li Y
... -
《-》
Hydroxysafflor yellow A of Carthamus tinctorius attenuates lung injury of aged rats exposed to gasoline engine exhaust by down-regulating platelet activation.
Long-term inhalation of gasoline engine exhaust (GEE) increases the risk of respiratory disease. Studies have suggested involvement of platelets in the development of some lung diseases. Hydroxysafflor yellow A (HSYA), a flavonoid compound, prevents hemostasis. Therefore, we investigated its effects on GEE-induced lung injury, and role of platelets in injury. Sixty-week-old male Sprague-Dawley rats were exposed to GEE for 4h/day for 6 weeks, and then grouped as follows: control, GEE, GEE+HSYA, GEE+HSYA+GW9662, and GEE+GW9662. Arterial oxygen tension (PaO2), carbon dioxide tension (PaCO2), pH, and the PaO2/fraction of inspired oxygen ratio (PaO2/FiO2) in the blood were detected using a blood gas analyzer. Wet/dry lung weight ratio, total protein in bronchoalveolar lavage fluid (BALF), and cytokine concentrations in serum and BALF were determined. Furthermore, cyclic adenosine monophosphate (cAMP) level and expression levels of target proteins were analyzed. Platelets were counted and their state was evaluated. HSYA attenuated GEE-mediated decreases in PaO2, PaO2/FiO2, platelet cAMP level, protein kinase A (PKA) activity, and peroxisome proliferator-activated receptor γ (PPARγ) expression. HSYA also attenuated GEE-mediated increases in lung permeability, cytokine levels in serum and BALF, plasma platelet count, and ADP-mediated platelet aggregation. Moreover, it suppressed GEE-induced increases in the expression of adhesion molecules and proinflammatory cytokines in platelets and lung tissue. Therefore, HSYA is therapeutically effective for GEE-mediated lung injury and acts by enhancing PKA activity and inhibiting platelet activation.
Wang C
,Wang C
,Ma C
,Huang Q
,Sun H
,Zhang X
,Bai X
... -
《-》