Vaccine adjuvant activity of a TLR4-activating synthetic glycolipid by promoting autophagy.

Toll-like receptors (TLRs) play crucial roles in host immune defenses. Recently, TLR-mediated autophagy is reported to promote immune responses via increasing antigen processing and presentation in antigen presenting cells. The present study examined whether the synthetic TLR4 activator (CCL-34) could induce autophagy to promote innate and adaptive immunity. In addition, the potential of CCL-34 as an immune adjuvant in vivo was also investigated. Our data using RAW264.7 cells and bone marrow-derived macrophages showed that CCL-34 induced autophagy through a TLR4-NF-κB pathway. The autophagy-related molecules (Nrf2, p62 and Beclin 1) were activated in RAW264.7 cells and bone marrow-derived macrophages under CCL-34 treatment. CCL-34-stimulated macrophages exhibited significant antigen-processing activity and induced the proliferation of antigen-specific CD4+T cells as well as the production of activated T cell-related cytokines, IL-2 and IFN-γ. Furthermore, CCL-34 immunization in mice induced infiltration of monocytes in the peritoneal cavity and elevation of antigen-specific IgG in the serum. CCL-34 treatment in vivo did not cause toxicity based on serum biochemical profiles. Notably, the antigen-specific responses induced by CCL-34 were attenuated by the autophagy inhibitor, 3-methyladenine. In summary, we demonstrated CCL-34 can induce autophagy to promote antigen-specific immune responses and act as an efficient adjuvant.

Depression by a green tea extract of alcohol-induced oxidative stress and lipogenesis in rat liver.

We determined the effects of a green tea extract with 36% alcohol on the blood alcohol content, oxidative stress, lipogenesis, inflammation and liver function of female Wistar rats. Tea alcohol significantly decreased the O2⁻, H2O2 and HOCl amounts via catechins and not caffeine. Thirty days of alcohol gavage improved the level of reactive oxygen species (ROS) in the liver, bile and blood, increased the 4-hydroxynonenal-protein adducts, Kupffer cell infiltration and lipid accumulation in the liver, and elevated the plasma alanine aminotransferase level. A western blot analysis showed reduced expression of the oxidative enzymes (CYP2E1 and NADPH oxidase p47phox protein) and lipogenic enzymes (SREBP-1c and fatty acid synthase) in the alcohol-treated liver. Tea alcohol significantly attenuated these elevated parameters. We conclude that the green tea extract in alcohol efficiently reduced the amounts of O2⁻, H2O2 and HOCl primarily due to the catechin content, and not caffeine. The developed tea liquor attenuated alcohol-induced oxidative injury and lipogenesis in the liver by the synergetic action of catechins and caffeine.

Emblica officinalis Gaertn. attentuates N-nitrosodiethylamine-induced apoptosis, autophagy, and inflammation in rat livers.

Inflammation and oxidative stress contribute to liver injury. Amla (Emblica officinalis Gaertn.) is rich in vitamin C, gallic acid, flavonoids, and tannins, which may protect against hepatoxicity-induced liver injury. We elucidated the effects of supplementary Amla (100 mg/kg of body weight) on N-nitrosodiethylamine-induced injury by evaluating reactive oxygen species (ROS) responses in the liver and bile, the degree of accumulated leukocytes and Kupffer cell infiltration, 3-nitrotyrosine and 4-hydroxynonenal stains, apoptosis and autophagy, plasma aspartate aminotransferase (AST), alanine aminotransferase (ALT), and γ-glutamyl transpeptidase (γ-GT) levels, and antioxidant/oxidant enzymes in rats. Amla was more potent than vitamin C in scavenging O2⁻·, hydrogen peroxide, and nitric oxide. N-Nitrosodiethylamine increased ROS production in liver and bile, hepatic Kupffer cell and leukocyte infiltration, 3-nitrotyrosine and 4-hydroxynonenal accumulations, apoptosis and autophagy, and plasma ALT, AST, and γ-GT levels in the rats, decreased hepatic manganese superoxide dismutase (MnSOD) and catalase protein expressions, and enhanced inducible nitric oxide synthase (iNOS) and cytochrome P450 2E1 (CYP2E1) protein expressions. Amla significantly preserved MnSOD and catalase expressions and decreased iNOS and CYP2E1 protein expressions in N-nitrosodiethylamine-treated livers. Amla decreased N-nitrosodiethylamine-enhanced hepatic apoptosis and autophagy appearances via down-regulation of the Bax/Bcl-2 ratio and Beclin-1 expression. Thus Amla supplementation counteracts N-nitrosodiethylamine-induced liver injury via its antioxidant, anti-inflammation, anti-apoptosis, and anti-autophagy properties.

Receptor binding activities of Chlorella on cysteinyl leukotriene CysLT, glutamate AMPA, ion channels, purinergic P 2Y, tachykinin NK2 receptors and adenosine transporter.

A Chlorella powder was tested in a total of 129 in vitro receptor binding assay systems. The results showed a potent inhibition of this powder on cysteinyl leukotriene CysLT2, and glutamate AMPA in a dose-concentration manner with IC(50) mean +/- SEM values of 20 +/- 4.5 microg/mL and 44 +/- 14 microg/mL, respectively. Other moderate and weak activities reflected in competitive binding experiments were seen versus adenosine transporter; calcium channel L-type, benzothiazepine; gabapentin; kainate, NMDA-glycine; inositol trisphosphate IP(3); cysteinyl CysLT(1), LTB(4); purinergic P(2Y); tachykinin NK(2); serotonin 5-HT(2B) and prostanoid, thromboxane A(2). Together, the results suggest that the various inhibitory effects of Chlorella powder in these receptor binding assays could reflect its actions in modulating Ca(2+)-dependent signal related targets and might be relevant to the mechanisms of its biological effects. These results reveal important potential biochemical activities that might be exploited for the prevention or treatment of several pathologies. From these results, the possible therapeutic usage of the product is discussed.

Chlorella powder inhibits the activities of peptidase cathepsin S, PLA2, cyclooxygenase-2, thromboxane synthase, tyrosine phosphatases, tumor necrosis factor-alpha converting enzyme, calpain and kinases.

A Chlorella powder was tested in 118 in vitro enzyme assay systems. The powder showed potent inhibitions of peptidase cathepsin S, thromboxane A(2) synthase and cyclooxygenase-2 in a dose-concentration manner with IC(50)+/-standard error of the mean values of 3.46+/-0.93 microg/ml, 3.23+/-0.69 microg/ml, and 44.26+/-9.98 microg/ml, respectively. Other activities observed were inhibitions of tumor necrosis factor-alpha converting enzyme, protein tyrosine phosphatase (SHP-2), calpain, protein kinases and protein tyrosine phosphatases. Chlorella powder had no significant effect on cyclooxygenase-1. These actions to inhibit cyclooxygenase-2 and thromboxane synthase could contribute to the purported anti-inflammatory and anti-thrombotic effects of Chlorella. These results reveal important potential biochemical activities to be developed that, if confirmed by in vivo studies, might be exploited for the prevention or treatment of several serious pathologies, including inflammatory diseases, immune and cancer.