Effect of biphenyl dimethyl dicarboxylate on the humoral immunosuppression by ethanol

Effect of glutamate and riluzole on manganese-induced apoptotic cell signaling in neuronally differentiated mouse P19 Cells

Excess exposure to Mn causes a neurological disorder known as manganism which is similar to dystonic movements associated with Parkinson's disease. Manganism is largely restricted to occupations in which high atmospheric levels are prevalent which include Mn miners, welders and those employed in the ferroalloy processing or related industrial settings. T1 weighted MRI images reveal that Mn is deposited to the greatest extent in the globus pallidus, an area of the brain that is presumed to be responsible for the major CNS associated symptoms. Neurons within the globus pallidus receive glutamatergic input from the subthalamic nuclei which has been suggested to be involved in the toxic actions of Mn. The neurotoxic actions of Mn and glutamate are similar in that they both affect calcium accumulation in the mitochondria leading to apoptotic cell death. In this paper, we demonstrate that the combination of Mn and glutamate potentiates toxicity of neuronally differentiated P19 cells over that observed with either agent alone. Apoptotic signals ROS, caspase 3 and JNK were increased in an additive fashion when the two neurotoxins were combined. The anti-glutamatergic drug, riluzole, was shown to attenuate these apoptotic signals and prevent P19 cell death. Results of this study confirm, for the first time, that Mn toxicity is potentiated in the presence of glutamate and that riluzole is an effective antioxidant which protects against both Mn and glutamate toxicity.

Diphenyl Dimethyl Bicarboxylate in the Treatment of Viral Hepatitis, Adjuvant or Curative?

Diphenyl dimethyl bicarboxylate (DDB) has been used in some countries as hepatoprotectant adjuvant in the treatment of liver diseases, such as chronic viral hepatitis, chemical or drug induced hepatic damage. Its early confirmed efficacy is to normalize elevated blood alanine aminotransferase (ALT) from different etiologies, however, it can rarely affect the rest hepatic enzymes. In addition, the lowering or normalization of ALT in most cases occurs during DDB treatment, withdrawal of DDB administration results in ALT re-elevated. Hence, for a long time, it has been only used as adjuvant of liver disease therapy. It is still controversial that whether DDB can be beneficial to liver histology. The normalization of ALT in hepatitis does not indicate therapeutic efficacy if without substantial liver histology improvement. In recent years, more studies showed that DDB might have new therapeutical potentials in liver diseases, it may have the effect of anti-viral, anti-malignancy. These new findings were mostly based on the in vitro or animal experiments, more basic studies and clinical trials are needed to ascertain these efficacies, prior to that stage, it is recommended to be cautious to apply DDB clinically for anti-virus and anti-malignancy purposes.

Immunological and hematological effects observed in B6C3F1 mice exposed to JP-8 jet fuel for 14 days

JP-8 is the primary jet fuel used by the U.S. Air Force and NATO allies. Exposure is likely to be widespread and to include both military and aviation industry personnel as well as residents living near fuel contaminated sites. This study examines the effects of JP-8 on humoral and cell-mediated and hematological parameters. A suite of immunotoxicological endpoints was evaluated in adult female B6C3F1 mice gavaged with JP-8 (in an olive oil carrier) ranging from 250-2500 mg/kg/d for 14 d. One day following the last exposure, significant increases in liver mass were detected beginning at exposure levels of 1000 mg/kg/d, while thymic mass was decreased at exposure levels of 1500 mg/kg/d and above. Decreases in thymic cellularity, however, were only observed at exposure levels of 2000 mg/kg/d and above. Mean corpuscular volume was increased (1500-2500 mg/kg/d), while the hematocrit, hemoglobin concentration, and red blood cell count were decreased only at the 2500 mg/kg/d exposure level. Natural killer cell (NK) activity and T- and B-cell proliferation were not altered. Decreases in the plaque-forming cell (PFC) response were dose responsive at levels of 500 mg/kg/d and greater, while unexpectedly, serum levels of anti-SRBC immunoglobulin M (IgM) were not altered. Alterations were detected in thymic and splenic CD4/8 subpopulations, and proliferative responses of bone marrow progenitor cells were enhanced in mice exposed to 2000 mg/kg/d of JP-8. This study establishes that humoral immune function is impaired with lower exposure levels of JP-8 than are required to affect primary and secondary immune organ weights and cellularities, CD4/8 subpopulations, and hematological endpoints.

Potentiation of the immunotoxicity of ethanol by acetaminophen in mice

To investigate the influences of acetaminophen (APP) on the immunotoxicity of ethanol (EtOH) in ICR mice, APP at a dose of 100 mg/kg was orally administered to mice daily for 28 consecutive days. Mice treated with EtOH were given freely with 20% w/v EtOH during the experimental period, and normal mice were given vehicle. The results of this study are summarized as follows: the combination of APP and EtOH significantly decreased the circulating leukocytes and the relative weights of liver, spleen and thymus, compared with the treatment of EtOH alone. In mice receiving the combination of AAP and EtOH when compared with the treatment of EtOH alone, there were also significant reductions in the splenic plaque forming cells (PFC) and hemagglutination (HA) titers to sheep red blood cells (SRBC), and the secondary IgG antibody response to bovine serum albumin (BSA). A tendency toward suppression of delayed-type hypersensitivity (DTH) reaction and phagocytic activity was also observed in the combination of AAP and EtOH. In addition, the combination of AAP and EtOH greatly increased serum alanine aminotransaminase (ALT) and total protein levels, compared with the treatment of EtOH alone. Significant decreases in serum albumin and A/G ratio were observed in EtOH alone-fed mice compared with those in normal animals, and their reductions were further induced in mice treated with AAP and EtOH. These findings indicate that EtOH-induced immunotoxicity is aggravated by the combination of APP and EtOH.