Poly-γ-glutamic acid (γ-PGA), naturally secreted from various strains ofBacillus, has anti-inflammatory activity. In inflammatory bowel disease (IBD), inflammation is promoted and sustained by angiogenesis; however, the role played byγ-PGA in this condition is unclear. Therefore, we evaluatedγ-PGA effects on angiogenesis and inflammation in a dextran sulfate sodium- (DSS-) induced mouse colitis model. Experimental colitis was induced in male C57BL/6 mice by administering 3% DSS. Disease activity index (DAI), histopathological scores, microvascular density, myeloperoxidase activity, and VEGF-A and VEGFR2 expression were compared among control mice, DSS-treated mice, and mice receiving 3% DSS along withγ-PGA at 50 mg/kg body weight per day or 3% DSS withγ-PGA at 200 mg/kg body weight per day. We found thatγ-PGA significantly attenuated weight loss, DAI, and colon shortening.γ-PGA also significantly reduced histopathological evidence of injury. Moreover,γ-PGA significantly attenuated DSS-induced blood vessel densities. Furthermore,γ-PGA attenuated DSS-induced expression of VEGF-A and its receptor, VEGFR2. In addition,γ-PGA treatment led to reduced recruitment of leukocytes to the inflamed colon. Therefore, our results indicate thatγ-PGA has potential application in conditions marked by inflammatory-driven angiogenesis and mucosal inflammation.

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease, and is associated with the development of metabolic syndrome. Postmenopausal women with estrogen deficiency are at a higher risk of progression to NAFLD. Estrogen has a protective effect against the progression of the disease. Currently, there are no safe and effective treatments for these liver diseases in postmenopausal women. Honokiol (Ho), a bioactive natural product derived from Magnolia spp, has anti-inflammatory, anti-angiogenic, and anti-oxidative properties. In our study, we investigated the beneficial effects of Ho on NAFLD in ovariectomized (OVX) mice. We divided the mice into four groups, as follows: SHAM, OVX, OVX+β-estradiol (0.4 mg/kg of bodyweight), and OVX+Ho (50 mg/kg of diet). Mice were fed diets with/without Ho for 12 weeks. The bodyweight, epidermal fat, and weights of liver tissue were lower in the OVX group than in the other groups. Ho improved hepatic steatosis and reduced proinflammatory cytokine levels. Moreover, Ho markedly downregulated plasma lipid levels. Our results indicate that Ho ameliorated OVX-induced fatty liver and inflammation, as well as associated lipid metabolism. These findings suggest that Ho may be hepatoprotective against NAFLD in postmenopausal women.

Allyl isothiocyanate (AITC) is a phytochemical found in cruciferous vegetables that has known chemopreventive and chemotherapeutic activities. Thus far, the antiangiogenic activity of AITC has not been reported in in vivo studies. Herein, we investigated the effect of AITC on angiogenesis and inflammation in a mouse model of colitis. Experimental colitis was induced in mice by administering 3% dextran sulfate sodium via drinking water. To monitor the activity of AITC in this model, we measured body weight, disease activity indices, histopathological scores, microvascular density, myeloperoxidase activity, F4/80 staining, inducible nitric oxide synthase (iNOS) expression, cyclooxygenase-2 (COX-2) expression, and vascular endothelial growth factor (VEGF)-A/VEGF receptor 2 (VEGFR2) expression in the mice. We found that AITC-treated mice showed less weight loss, fewer clinical signs of colitis, and longer colons than vehicle-treated mice. AITC treatment also significantly lessened the disruption of colonic architecture that is normally associated with colitis and repressed the microvascularization response. Further, AITC treatment reduced both leukocyte recruitment and macrophage infiltration into the inflamed colon, and the mechanism these activities involved repressing iNOS and COX-2 expression. Finally, AITC attenuated the expression of VEGF-A and VEGFR2. Thus, AITC may have potential application in treating conditions marked by inflammatory-driven angiogenesis and mucosal inflammation.

We investigated the hepatoprotective effects of the extract of dandelion leaves (EDL) on a murine model of methionine- and choline-deficient (MCD) diet-induced nonalcoholic steatohepatitis (NASH). C57BL/6 mice were fed for 4 weeks with one of the following diets: control diet (Cont), MCD diet (MCD), MCD diet supplemented with EDL at 200 mg/kg body weight·daily (MCD+D200), and MCD diet supplemented with EDL at 500 mg/kg body weight·daily (MCD+D500). Hepatic function was assessed by evaluating the following parameters: liver histology; plasma levels of alanine aminotransferase (ALT), triglyceride (TG), malondialdehyde (MDA), and reduced glutathione (GSH); expression levels of TNF-α and IL-6; and levels of caspase-3 and pJNK/JNK protein. Histopathological evaluations revealed that addition of EDL to the MCD diet dampens the severity of the clinical signs of NASH. Moreover, EDL led to a significant decrease in the serum levels of ALT, hepatic TG, and MDA, and in the expression levels of TNF-α, and IL-6; on the contrary, the levels of reduced GSH increased. At the post-transcriptional level, EDL significantly decreased the activation of procaspase-3 to active caspase-3, and the phosphorylation of JNK. These results suggest that the beneficial effects of EDL on NASH are mainly due to its antioxidant and anti-inflammatory activities.

Inflammatory bowel disease (IBD) is characterized by inflammation, angiogenesis, and lymphangiogenesis. Artemisinin (Art), a chemical compound isolated from Artemisia annua L. (sweet wormwood), has several biochemical properties including antibacterial, anticancer, anti-inflammation, and anti-angiogenesis effects. We investigated the effects of Art on inflammation-induced lymphangiogenesis in a dextran sulfate sodium (DSS)-induced mouse acute colitis model. The mice were orally administered Art for 7 days before being evaluated using the disease activity index (DAI) and documenting colonic inflammatory changes, colon edema, microvessel density, lymphatic vessel density (LVD), proinflammatory cytokine levels, and vascular endothelial growth factor (VEGF)-C and VEGF-D/VEGF receptor (VEGFR)-3 mRNA expression levels in colon tissue. Art reduced DSS-induced lymphatic vessel endothelial hyaluronan receptor-1-positive LVD. Art also reduced the symptoms of colitis, improved tissue histology, and relieved inflammatory edema in mice affected by colitis. In addition, Art decreased the infiltration of immunomodulatory cells and inflammatory cytokines, which involved reduction of VEGF-C, -D, and VEGFR-3 expression. Taken together, our findings suggest that Art ameliorates inflammation-driven lymphangiogenesis in an experimental colitis mouse model via the VEGF-C/VEGFR-3 signaling pathway, implicating this pathway as a potential target for the treatment of IBD.