Hesperetin derivative-12 (HDND-12) regulates macrophage polarization by modulating JAK2/STAT3 signaling pathway / 中国天然药物

Macrophages show significant heterogeneity in function and phenotype, which could shift into different populations of cells in response to exposure to various micro-environmental signals. These changes, also termed as macrophage polarization, of which play an important role in the pathogenesis of many diseases. Numerous studies have proved that Hesperidin (HDN), a traditional Chinese medicine, extracted from fruit peels of the genus citrus, play key roles in anti-inflammation, anti-tumor, anti-oxidant and so on. However, the role of HDN in macrophage polarization has never been reported. Additional, because of its poor water solubility and bioavailability. Our laboratory had synthesized many hesperidin derivatives. Among them, hesperidin derivatives-12 (HDND-12) has better water solubility and bioavailability. So, we evaluated the role of HDND-12 in macrophage polarization in the present study. The results showed that the expression of Arginase-1 (Arg-1), interleukin-10 (IL-10), transforming growth factor β (TGF-β) were up-regulated by HDND-12, whereas the expression of inducible Nitric Oxide Synthase (iNOS) was down-regulated in LPS- and IFN-γ-treated (M1) RAW264.7 cells. Moreover, the expression of p-JAK2 and p-STAT3 were significantly decreased after stimulation with HDND-12 in M1-like macrophages. More importantly, when we taken AG490 (inhibitor of JAK2/STAT3 signaling), the protein levels of iNOS were significantly reduced in AG490 stimulation group compare with control in LPS, IFN-γ and HDND-12 stimulation cells. Taken together, these findings indicated that HDND-12 could prevent polarization toward M1-like macrophages, at least in part, through modulating JAK2/STAT3 pathway.

Transforming growth factor-β and renal fibrosis / 生理学报

Transforming growth factor-β (TGF-β) is a driving force of renal fibrosis, which may lead to chronic kidney diseases and even end stage renal diseases. By activating canonical and non-canonical signaling pathways, TGF-β promotes the synthesis of extracellular matrix while preventing their degradation. In the injured kidney, TGF-β induces apoptosis, proliferation and fibrotic response of renal cells including epithelial cells, endothelial cells, podocytes, fibroblasts, pericytes and macrophages, and it also promotes transdifferentiation, activation and proliferation of myofibroblasts. Additionally, TGF-β exerts profibrotic effects by interplaying with other signaling pathways like BMP-7, Wnt/β-catenin and MAP kinase. Smad3 is the central pathological gene in renal fibrosis, and epigenetic regulation of TGF-β/Smad3 is a hot topic in kidney field. Although direct targeting TGF-β may cause side effects including tumorigenesis and immune diseases, the therapeutic strategies targeting the balance of downstream Smad3 and Smad7 may prevent or delay the progression of fibrotic kidney disease.

Alcohol promotes renal fibrosis by activating Nox-mediated DNA methylation of Smad7 / 中国药理学与毒理学杂志

OBJECTIVE Alcohol is mainly metabolized through liver and excreted by kidney in the body. Kidney damage has been considered as the secondary to liver injury and kidney dysfunction is common in hospitalized patients with severe alcoholic hepatitis. Both acute and chronic alcoholism accumulation can compromise kidney function, although alcoholic kidney disease has drawn much more attention recently,the methodology for establishing the in vivo and in vitro alcoholic renal fibrosis models are still lacking,and the underlying mechanisms are to be determined. METHODS and RESULTS Mice were feed with a liquid diet containing alcohol for 4 weeks, 8 weeks and 12 weeks respectively, results of Masson′s Trichrome staining showed that kidney fibrosis peaked in 8-week model group, which consistent with the results of albumin assay,Western blot,immunostaining and real-time PCR of collagen I and α-SMA.In vitro study also confirmed that ethanol upregulated the level of fibrotic index-es,including collagen I and α-SMA,in tubular epithelial cells(HK2 cells).Additionally,both in vivo and in vitro studies showed that Smad7 was decreased and Smad3 was highly activated. Then we further detected the underlying mechanisms by which alcohol induced the imbalance of Smad7 and Smad3. Results of Genome-wide methylation sequencing found DNA methylation of Smad7 in the alcoholic fibrosis kidney,which may be mainly mediated by DNA methyltransferase 1(DNMT1),because knock-down of DNMT1,but not DNMT2 and 3,largely restored Smad7 level in ethanol-treated HK2 cells.Con-sequently, we found that NADPH Oxidases (nox)-mediated oxidative stress is the major force upregu-lating DNMT1,since knockdown of Nox2 and 4 could both decrease DNMT1 while rebalancing Smad7/Smad3 axis, and thereby relieved ethanol-induced fibrotic response in HK2 cells. More importantly, intraperitoneal injection of apocynin,an inhibitor of NADPH oxidoreductase,attenuated renal fibrosis in alcoholic kidney fibrosis mouse model. CONCLUSION By establishing the novel in vivo and in vitro models,we found that through activating oxidative stress-induced DNA methylation of Smad7,alcohol induces renal fibrosis by breaking the balance between Smad7 and Smad3.Elimination of Nox-mediated oxidative stress may be a potential therapy for treatment of long-term alcohol abuse-induced kidney fibrosis.