Silver nitrate administration stimulates immune activation, inflammation and deterioration in cell function. It is well established that hippocampal and cortical tissue are susceptible to degeneration in responses to insult such as oxidative stress or infection. This study was designed to investigate the prophylactic effect of alpha-crystallin, a major chaperone lens protein comprising of alpha-A and alpha-B subunits in inflammation induced mice. Mice were divided into three groups (n=6 in each), control, inflammation and alpha-crystallin treated. Our result shows that alpha-crystallin pretreatment effectively diminished systemic inflammation induced glial fibrillary acidic protein (GFAP) and nuclear factor kappa B (NFkappaB) expression in the mice neocortex, reversed elevated intracellular calcium levels, acetylcholine esterase activity and depletion of glucose. Furthermore it also significantly prevented nitric oxide (P<0.05) and lipid peroxide production in the plasma, liver, neocortex and hippocampus of the inflammation-induced mice. In order to demonstrate the direct *OH and nitric oxide radical scavenging ability of alpha-crystallin, an In vitro experiment using primary astrocyte culture subjected to lipopolysaccharide (LPS), a well-known inflammatory stimuli were also carried out. This study reiterates that alpha-crystallin therapy may serve as a potent pharmacological agent in neuroinflammation.

Molecular chaperones protect cells from the deleterious effects of protein misfolding and aggregation. Neurotoxicity of amyloid-beta (Aβ) aggregates and their deposition in senile plaques are hallmarks of Alzheimer's disease (AD). We observed that the overall content of αB-crystallin, a small heat shock protein molecular chaperone, decreased in AD model mice in an age-dependent manner. We hypothesized that αB-crystallin protects cells against Aβ toxicity. To test this, we crossed αB-crystallin/HspB2 deficient (CRYAB-/-HSPB2-/-) mice with AD model transgenic mice expressing mutant human amyloid precursor protein. Transgenic and non-transgenic mice in chaperone-sufficient or deficient backgrounds were examined for representative behavioral paradigms for locomotion and memory network functions: (i) spatial orientation and locomotion was monitored by open field test; (ii) sequential organization and associative learning was monitored by fear conditioning; and (iii) evoked behavioral response was tested by hot plate method. Interestingly, αB-crystallin/HspB2 deficient transgenic mice were severely impaired in locomotion compared to each genetic model separately. Our results highlight a synergistic effect of combining chaperone deficiency in a transgenic mouse model for AD underscoring an important role for chaperones in protein misfolding diseases.

During the course of cancer radiation treatment, normal skin invariably suffers from the cytotoxic effects of gamma-radiation and reactive oxygen species (ROS), which are generated from the interaction between radiation and the water molecules in cells. The present study was designed to investigate the radioprotective role of alpha-lipoic acid (LA), an antioxidant on murine skin fibroblasts exposed to a single dose of 2, 4, 6, or 8Gy gamma-radiation. Irradiation of fibroblasts significantly increased ROS, nitric oxide, and lipid peroxidation (P < 0.001); all of these factors substantially decreased with 100 microM LA treatment. Hydroxyl radical (OH(.)) production from 8Gy irradiated fibroblasts was measured directly by electron spin resonance using spin-trapping techniques. LA was found to inhibit OH(.) production at 100-microM concentrations. Dose-dependent depletion of antioxidants, such as catalase and glutathione reductase, was observed in irradiated fibroblasts (P < 0.001), along with increased superoxide dismutase (P < 0.001). LA treatment restored antioxidant levels. Concentration of the pro-inflammatory cytokine IL-1beta was significantly reduced in irradiated fibroblasts when treated with LA. MTT and lactate dehydrogenase assays demonstrated that LA treatment reduced cell injury and protected cells against irradiation-induced cytotoxicity. Thus, we conclude that results are encouraging and need further experiments to demonstrate a possible benefit in cancer patients and the reduction of harmful effects of radiation therapy.

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Acute inflammation can activate macrophages or monocytes and subsequently release several inflammatory cytokines and reactive oxygen species (ROS). Oxidative stress triggered by the production of ROS plays deleterious role leading to multiple organ failure. This study was designed to investigate the prophylactic effect of alpha-crystallin, a major chaperone lens protein comprising of alpha-A and alpha-B subunits in inflammation-induced mice. Mice were divided into three groups (n=6 in each): control, inflammation and alpha-crystallin-treated. Results show that ROS was significantly higher in the lymphocytes, hepatocytes and astrocytes (P<0.05) of inflammation-induced mice when compared to control, but no significant changes were observed in the alpha-crystallin-treated group. Increased level of lipid peroxidation (LPO) and decreased activities of antioxidant such as superoxide dismutase (SOD), catalase, glutathione peroxidase and glutathione were observed in the inflammation-induced mice when compared to control, whereas the activities of these were found to be normal followed by alpha-crystallin treatment. We also observed a reduction in reduced glutathione levels in hepatocytes of inflammation-induced mice, which were normalized on alpha-crystallin treatment. The in vitro study has shown that alpha-crystallin treatment not only suppresses the increase in LPO levels but also inhibits the lipid breakdown resulting from autooxidation in mouse cerebral cortex homogenate, and strongly suggests that alpha-crystallin therapy may serve as a potent pharmacological agent in systemic inflammation.