Ulcerative colitis (UC) is an inflammatory bowel disease accompanied by abdominal pain, diarrhea, and rectal bleeding. The aim of this study was to investigate whether puerarin, one of the main components of the root of Pueraria lobata, exerts anti-inflammatory and anti-oxidative effects against UC. To examine the anti-inflammatory and anti-oxidative effects of puerarin against colitis, we used a mouse model of dextran sulfate sodium (DSS)-induced colitis. Administration of puerarin alleviated colon shortening, pathological damage to the colon, and myeloperoxidase (MPO) activity. Puerarin significantly inhibited inflammation through the down-regulation of nuclear factor-κB (NF-κB) and the secretion of pro-inflammatory mediators. Moreover, puerarin showed anti-oxidative effects through the regulation of the expression of the NF-E2 p45-related factor 2 (Nrf2) pathway and antioxidant enzymes. Puerarin inhibited intestinal epithelial barrier dysfunction by increasing the expression of tight junction proteins. These results suggest that puerarin has anti-inflammatory and anti-oxidative effects in the mouse model of colitis.

Metastatic melanoma is one of the most deadly and evasive cancers. Collagen I in the extracellular matrix promotes the migration and invasion of tumor cells through the production of matrix metalloproteinase (MMP) 2 and 9. Discoidin domain receptor (DDR) 2 is a collagen receptor that is implicated in several cancer types including breast and prostate cancers. However, the role of DDR2 in the migration and invasion of murine melanoma cells is less studied. In the present study, we investigated the effects and underlying mechanisms of DDR2 in migration and invasion of B16BL6 melanoma cells in response to collagen I. Results demonstrated that DDR2 is expressed and is phosphorylated by collagen I in the cells. Upon down-regulation of DDR2 using small-interfering RNA (siRNA) approach, both of the cell migratory and invasive phenotypes were significantly attenuated when compared with the control cells. This effect was mediated via suppression of MMP2/9 upon DDR2 inhibition. Furthermore, inhibition of DDR2 by specific siRNA markedly reduced the activation of extracellular regulated kinase (ERK) 1 and 2 and nuclear factor of kappa B (NF-κB) in the cells when compared with the control cells. Overall, these data demonstrated that DDR2 siRNA-mediated suppression of ERK1/2 and NF-κB could down-regulate the expressions of MMP2/9 in response to collagen I to reduce the migratory and invasive phenotypes of the cells.

The present study aimed to compare the potential anti-adipogenic effects and underlying mechanisms of the luteolin, isoscoparin and isoorientin flavonoids, purified from Triticum aestivum sprout (TA) in 3T3-L1 cells. The cells were treated with different concentrations of flavonoids for 8 days and the lipid accumulation was assessed using Oil-Red-O staining. The expression levels of the transcription factors and the genes involved in adipogenesis in the cells were assessed by reverse transcription-quantitative polymerase chain reaction and western blotting. The results demonstrated that 10 μM luteolin, isoscoparin or isoorientin inhibited lipid deposition in the cells by 74, 63 and 65%, respectively. The flavonoids also significantly inhibited the transcriptional regulators of adipogenesis, including peroxisome proliferator-activated receptor-γ, CAAT/enhancer binding protein-α and sterol regulatory element binding protein (SREBP)-1c, compared with the control cells. Similarly, there was a significant downregulation of the adipocyte specific markers associated with lipid metabolism, including activating protein-2, fatty acid synthase, hormone-sensitive lipase and lipoprotein lipase, in the flavonoid treated cells. Notably, the cells treated with the flavonoids demonstrated increased expression levels of the insulin-induced genes, insig-1 and insig-2, which may have inhibited the activation of the adipogenic transcription factor, SREBP, eventually leading to the inhibition of adipogenesis. Taken together, these results revealed that the flavonoids from TA possessed an inhibitory effect on adipogenesis through downregulation of adipogenic transcription factors and genes associated with lipid metabolism, and the upregulation of insig 1 and 2, suggesting that the flavonoids from TA may be potential therapeutic agents for the prevention and treatment of obesity.

C1q is known to perform several functions in addition to the role it plays in complement activation. C1q contains a collagen-like portion and DDR1 (discoidin domain receptor 1) is a well-known collagen receptor. Accordingly, we hypothesized C1q might be a novel ligand of DDR1. This study shows for the first time C1q directly induces the activation and upregulation of DDR1, and that this leads to enhanced migration and invasion of HepG2 cells. In addition, C1q was found to induce the activations of mitogen-activated protein kinases (MAPKs) and phosphoinositide 3-kinase (PI3K)/Akt signaling, and to increase the expressions of matrix metalloproteinases (MMP2 and 9). Our results reveal a relationship between C1q and DDR1 and suggest C1q-induced DDR1 activation signaling may be involved in the progression of hepatocellular carcinoma.