Angiogenesis is implicated in diverse pathological conditions such as cancer, rheumatoid arthritis, psoriasis, atherosclerosis, and retinal neovascularization. In the present study, we investigated the effects of modified rice bran hemicellulose (MRBH), a water-soluble hemicellulose preparation from rice bran treated with shiitake enzymes, on vascular endothelial growth factor (VEGF)-induced angiogenesis in vitro and its mechanism. We found that MRBH significantly inhibited VEGF-induced tube formation in human umbilical vein endothelial cells (HUVECs) co-cultured with human dermal fibroblasts. We also observed that MRBH dose-dependently suppressed the VEGF-induced proliferation and migration of HUVECs. Furthermore, examination of the anti-angiogenic mechanism indicated that MRBH reduced not only VEGF-induced activation of VEGF receptor 2 but also of the downstream signaling proteins Akt, extracellular signal-regulated protein kinase 1/2, and p38 mitogen-activated protein kinase. These findings suggest that MRBH has in vitro anti-angiogenic effects that are partially mediated through the inhibition of VEGF signaling.
Lactobacillus paracasei K71 was shown to be effective in alleviating the severity of atopic dermatitis in a randomized controlled trial, and a preliminary open-label trial suggested that strain K71 intake enhanced secretory immunoglobulin A (sIgA) release in the saliva. This study investigated the effect of K71 on sIgA release in a randomized, double-blind, placebo-controlled, parallel-group trial. The trial included 62 Japanese subjects aged 20–64 years with relatively low rates of salivary sIgA release. Subjects (n=31 in each group) were randomly given a tablet containing 100 mg (approximately 2 × 1011 bacteria) of K71 or a placebo tablet daily for 12 weeks. After eliminating data for eight subjects (four in each group) who met the exclusion criteria for efficacy analysis, data for 54 subjects were analyzed. The change in the rate of salivary sIgA release 8 weeks after initiation of the study compared with baseline was significantly higher in the K71 tablet group (105.5 ± 119.0 µg/min) than in the placebo group (52.7 ± 62.6 µg/min; p=0.047). There were no adverse events associated with intake of tablets containing K71. The safety of intake of L. paracasei K71 was also confirmed in an independent open-label trial with 20 healthy subjects who consumed excessive amounts of K71-containing food. L. paracasei K71 intake may therefore have some benefits in promoting mucosal immune function.
Penicillin-binding proteins (PBPs) are responsible for peptidoglycan synthesis. By using biotinylated ampicillin, we detected PBPs of Lactobacillus paracasei strains. Ten PBPs were identified, 7 of which had apparent molecular sizes similar to those of Escherichia coli. In the presence of cholate, strain NRIC 0625 showed an elongated shape, and its putative PBP3 showed cholate-sensitive penicillin-binding activity. Furthermore, this strain was highly sensitive to cefalexin, which is known to inhibit cell division by inactivating PBP3. These results suggest that the septum synthetase PBP3 of lactic acid bacteria can be one of the targets of intestinal bile acid.