Long-term exposure to low lithium concentrations stimulates proliferation, modifies stress protein expression pattern and enhances resistance to oxidative stress in SH-SY5Y cells.

SH-SY5Y cells, derived from a human neuroblastoma, were submitted to short- or long-term exposures to lithium carbonate concentrations ranging from 0.5 to 8 mM. Short-term exposures (4 days) to concentrations higher than 6 mM were found to reduce cell growth rate while exposure to 8 mM resulted in significant cell mortality. These ranges of concentrations induced an overexpression of (1) the HSP27 stress protein, (2) a 108 kDa protein (P108) recognized by an anti-phospho-HSP27(Ser78) antibody, and probably corresponding to a phosphorylated HSP27 tetramer, (3) a 105 kDa protein (P105), possible glycosylated or phosphorylated form of the GRP94 stress protein and (4) a phosphorylated (inactivated) form of glycogen synthase kinase (GSK3alpha/beta) SH-SY5Y cells, when cultured in the presence of 0.5 mM lithium for 25 weeks, displayed interesting features as compared to controls: (1) higher cell growth rate, (2) increased resistance toward the inhibitory effects of high lithium concentrations on cell proliferation, (3) lower basal level of lipid peroxidation (TBARS) and improved tolerance to oxidative stress induced by high lithium concentrations, (5) reduced expression of monomeric HSP27 versus an increase of corresponding tetrameric protein (P108) and (6) overexpression of a 105 kDa protein (P105). In conclusion, our study suggests that chronic treatment (over several months) by therapeutic relevant lithium concentrations could favour neurogenesis, decrease the vulnerability of neuronal cells to oxidative stress and induce posttranslational changes of molecular chaperones.

Effect of selected insecticides on growth rate and stress protein expression in cultured human A549 and SH-SY5Y cells.

Two organochlorines (dienochlor, endosulfan) and one neonicotinoid (imidacloprid) insecticides were investigated as putative cellular aggressors, both as pure chemicals and as commercial formulations, in order to evaluate the additional toxicity due to additives present in the commercial formulations. Toxicity was evaluated on human cells in vitro, by culturing neuronal SH-SY5Y and pulmonary A549 cell lines for 3 days in the presence of increasing concentrations of the selected pesticides. LOEC (lowest observed effect concentration), IC50 (concentration leading to a 50% decrease of cell growth) and expression changes of molecular chaperones involved in cellular protein quality control were determined. The investigated molecular chaperones were the cytosolic resident heat shock proteins (HSP27, HSP72/73, and HSP90) and the glucose regulated proteins (GRP78, GRP94) located in the endoplasmic reticulum (ER). Organochlorines were found to be the most toxic in both A549 and SH-SY5Y cells, IC50 being respectively 0.95 and 0.36 microM for dienochlor, 34 and 20 microM for endosulfan, 1.8 and 1.5 mM for imidacloprid. This shows that neuronal cells were more sensitive than pulmonary cells. LOEC and IC50 appeared at lower concentrations of active molecule when using the commercial formulations Techn'ufan (endosulfan) and Confidor (imidacloprid), indicating an additional adverse effect of additives. Insecticide concentrations higher than IC50 were found to induce an underexpression of all cytosolic HSPs, probably resulting from a general inhibition of protein synthesis. HSP27 was found to be underexpressed at concentrations of imidacloprid or endosulfan (as Techn'ufan) lower than IC50. This underexpression of the anti-apoptotic HSP27 could contribute to the increase of cell mortality. GRP78 was up-regulated by endosulfan in A549, but not in SH-SY5Y cells, suggesting a damaging effect on proteins specific to pulmonary cells. Conversely, HSP72/73 was found to be down-regulated, resulting probably from the ER unfolded protein response (UPR) as previously reported [Skandrani, D., Gaubin, Y., Vincent, C., Beau, B., Murat, J.C., Soleilhavoup, J.P., Croute, F., 2006. Relationship between toxicity of selected insecticides and expression of stress protein (HSP, GRP) in cultured human cells: effects of commercial formulations versus pure active molecules. Biochim. Biophys. Acta 1760 (1), 95-103].

Stress proteins induced by exposure to sublethal levels of heavy metals in sea bream (Sparus sarba) blood cells.

Blood cells freshly collected from silver sea bream (Sparus sarba) were exposed in vitro to different sublethal concentrations of cadmium(II), lead(II) or chromium(VI). HSP70 stress proteins were significantly overexpressed after exposure to metal concentration as low as 0.1 microM. Under our experimental conditions, no overexpression of metallothioneins in blood cells was evidenced. Our results show that fish blood cells may constitute an interesting biological model for experimental and applied toxicology, especially in the case of environmental pollution.

Stress proteins (Hsp72/73, Grp94) expression pattern in rat organs following metavanadate administration. Effect of green tea drinking.

Expression pattern of heat shock proteins (Hsp) 72/73 and glucose regulated protein (Grp) 94 was studied in liver, kidney and testis of rats injected with sublethal doses of ammonium metavanadate (5 mg/kg/day). In addition, some batches of animals were given green tea decoction, known to be rich in anti-oxidative compounds, as sole beverage in order to evaluate its protective properties. In control animals, the stress proteins expression was found to be organ-dependent: anti-Grp94 antibody revealed two bands at 96 and 98 kDa in kidney and liver whereas the 98 kDa band only was found in testis; anti-Hsp72/73 antibody revealed that the constitutive Hsp73 was present in all organs whereas the inducible Hsp72 was only present in kidney and testis. In kidney of vanadium-treated rats, Hsp73 was over-expressed by about 50% whereas Hsp72 was down-regulated by 50-80%. No such effects were observed in liver and testis. In liver and kidney of vanadium-treated rats, Grp94 was over-expressed by 50% and 150% respectively whereas no change was found in testis. In rats given green tea as sole beverage, the 96 kDa protein expression level in liver was reduced both in controls and in vanadium-treated animals. However, green tea drinking failed to prevent the vanadium-induced Hsp72 under-expression in kidney of vanadium-treated rats.

Changes in growth rate and thyroid- and sex-hormones blood levels in rats under sub-chronic lithium treatment.

Lithium therapy, mainly used in curing some psychiatric diseases, is responsible for numerous undesirable side effects. The present study is a contribution to the understanding of the pathophysiological mechanisms underlying lithium toxicity. Male and female mature rats were divided into three batches and fed commercial pellets: one batch was the control and the second and third batches were given 2 g (Li1) and 4 g (Li2) of lithium carbonate/kg of food/day, respectively. After 7, 14, 21 and 28 days, serum levels of free tri-iodothyronine (FT3), thyroxine (FT4), testosterone and estradiol were measured. Attention was also paid to growth rate and a histological examination of testes or vaginal mucosa was carried out. In treated rats, a dose-dependent loss of appetite and a decrease in growth rate were observed, together with symptoms of polydypsia, polyuria and diarrhea. Lithium serum concentrations increased from 0.44 mM (day 7) to 1.34 mM (day 28) in Li1 rats and from 0.66 to 1.45 mM (day 14) in Li2 rats. Li2 treatment induced a high mortality after 14 days, reaching 50-60% in female and male animals. From these data, the LD50 (14 days Li2 chronic treatment) was calculated to be about 0.3 g/day per kilogram of animal, leading to Li serum concentrations of about 1.4 mM. A significant decrease of FT3 and FT4 was observed in treated rats. This effect appeared immediately for the highest dose and was more pronounced for FT3, resulting in an increase of the FT4/FT3 ratio. In males, testosterone decreased and spermatogenesis was stopped. Conversely, in females, estradiol increased in a dose-dependent manner as the animals were blocked in the diestrus phase at day 28. This finding supports a possible antagonistic effect of lithium on the estradiol receptors.

Growth-related enzymatic control of glycogen metabolism in cultured human tumor cells.

The activities of glycogen synthase and phosphorylase were measured and compared to the growth-related variations of glycogen accumulation in three cultured human tumor cell lines: HT-29 (colon carcinoma); MeWo (malignant melanoma); and RT-4 (carcinoma of the urinary bladder). A similar pattern of variations in the enzyme activities was found in the three cell lines. The activities of the a + b forms of glycogen phosphorylase increased throughout the culture period. Maximal activity of phosphorylase a coincided with low intracellular concentrations of glycogen during the period of exponential growth. When the rate of cell division decreased, phosphorylase a activity also decreased while the glycogen levels increased. Glycogen synthase was almost entirely in b form during the entire culture period, i.e., in both the exponential and the stationary phases. In vitro incubation of the cellular extracts without NaF showed, however, that the enzyme could be partially converted to the a form by the endogenous phosphatases. The A0.5 values of the enzyme for glucose-6-phosphate (Glc-6-P) were of the same order of magnitude as the intracellular Glc-6-P concentrations which ranged from 2.2 to 5.4 mM (almost 10 times those reported in normal cells). Similar Glc-6-P values were obtained by two different extraction methods controlled by the intracellular ATP and ADP concentrations. The Km values for uridine-5'-diphosphoglucose were always 2 to 3 times lower than the intracellular uridine-5'-diphosphoglucose concentrations. These results suggest that: (a) in these tumor cells, glycogen is essentially synthesized by glycogen synthase b via an allosteric activation by intracellular Glc-6-P; (b) there is no obvious growth-related control of glycogen synthase activity; and (c) the activity of glycogen phosphorylase seems to be growth dependent with maximal phosphorylase a activities associated with the period of high division rate.

Regulation of mitochondrial hexokinase in cultured HT 29 human cancer cells. An ultrastructural and biochemical study.

The involvement of the mitochondrial bound hexokinase in aerobic glycolysis was investigated in two subpopulations of the HT 29 human colon cancer cell line: a poorly differentiated one with high aerobic lactate production (referred as undifferentiated or standard cells), and an enterocyte-like differentiated one with lower lactate production (referred as differentiated or Glc- cells). After mild digitonin treatment, 85% of the total cellular hexokinase activity remained in the particulate fraction in both cell types. In both cases mitochondria appeared to be tightly coupled but the Glc- cells exhibited a significantly higher oxidation rate in the presence of glucose. Electron microscopy of freeze-fractured cells revealed the absence of contacts between the two limiting mitochondrial membranes in the highly glycolytic standard cells, whereas the contacts were present in the Glc- cells. Furthermore, we investigated the functional relationship between bound hexokinase (as hexokinase-porin complex) and the inner compartment of mitochondria isolated from standard and Glc- HT 29 cells. In contrast to the differentiated cells the hexokinase in undifferentiated standard cells was not functionally coupled to the oxidative phosphorylation. This suggests that the high rate of lactate formation in neoplastic cells is not caused by an increase of particulate hexokinase activity but rather by a disregulation of the hexokinase-porin complex caused by the absence of contact sites between the two mitochondrial membranes. In agreement with this interpretation, the hexokinase-porin complex could be completely removed by digitonin treatment in standard HT 29 cells, while this was not possible in mitochondria from Glc- cells.

Study on ATP-generating system and related hexokinase activity in mitochondria isolated from undifferentiated or differentiated HT29 adenocarcinoma cells.

The functional properties of mitochondria bound hexokinase are compared in two subpopulations of the HT29 human colon cancer cell-line: (1) the HT29 Glc+ cells, cultured in the presence of glucose, which are poorly differentiated and highly glycolytic and (2) the HT29 Glc- cells, adapted to grow in a glucose-free medium, which are 'enterocyte-like' differentiated and less glycolytic when given glucose (Zweibaum et al. (1985) J. Cell Physiol. 122, 21-28). The activities of hexokinase, phosphofructokinase-1 and pyruvate kinase are found to be twice as high in Glc+ cells when compared to Glc- cells. Besides, the respiration rate is decreased in Glc+ cells compared to Glc- cells. These results correlate with the higher glycolytic rate in Glc+ cells. In many tissues, it has been shown that the binding of hexokinase to the mitochondrial outer membrane allows a preferential utilization of the ATP generated by oxidative phosphorylation which, in turn, is activated by immediate restitution of ADP. In highly glycolytic cancer cells, although a large fraction of hexokinase is bound to the mitochondria, the existence of such a channeling of nucleotides is still poorly documented. The rates of glucose phosphorylation by bound hexokinase were investigated in mitochondria isolated from both Glc+ and Glc- cells either with exogenous ATP or with ATP generated by mitochondria supplied with ADP and succinate (endogenous ATP). Diadenosine pentaphosphate (Ado2P5), oligomycin and carboxyatractyloside (CAT) were used in combination or separately as metabolic inhibitors of adenylate kinase, ATP synthase and ATP/ADP translocator, respectively. Exogenous ATP appears to be 6.5-times more efficient than endogenous ATP in supporting hexokinase activity in the mitochondria from Glc+ cells and only 1.8-times cells. The rate of oxidative phosphorylation being higher in mitochondria from Glc- cells, hexokinase activity is higher in this model when ATP is generated by respiration. Furthermore, in Glc+ mitochondria, the adenylate kinase reaction appears to be an important source of endogenous ATP for bound hexokinase, while, in Glc- mitochondria, hexokinase activity is almost totally dependent on the ATP generated by oxidative phosphorylation. This result might be explained by our previous finding that mitochondria from Glc+ cells lack contact sites between outer and inner membrane, whereas numerous contacts were observed in mitochondria from Glc- cells (Denis-Pouxviel et al. (1987) Biochim. Biophys. Acta 902, 335-348).

Volatile organic compounds cytotoxicity and expression of HSP72, HSP90 and GRP78 stress proteins in cultured human cells.

The aim of this study was to determine whether overexpression of stress proteins (SPs) could be a sensitive biomarker for cell injury due to exposure to low doses of volatile organic compounds (VOCs) such as benzene, ethylbenzene, toluene, xylene, and chlorinated derivatives (ClB). Sublethal and cytotoxic threshold concentrations of the VOCs were determined by studying the growth rate of normal (fibroblasts) or tumor-derived human cell lines (A549, HepG2) exposed for 4 days to VOCs. Changes in SP expression as a function of concentrations were investigated by Western blotting.VOC toxicity was found to be correlated with their degree of chlorination and their hydrophobicity. Cytotoxic threshold concentrations (no-observed effect concentration, NOEC) were found to be similar for the three cell lines. It was observed that using a mixture of VOCs, each of them at concentration below the NOEC, resulted in an actual toxicity to the cells. This finding reveals a synergistic effect and should be taken into account when assessing threshold risk and exposure limit values in the worker's environment when several pollutants may be present. HSP72 and HSP90 expression levels were not affected whereas GRP78 expression was increased by all the VOCs. Taking into account the specific molecular function of GRP78, it suggests that VOC exposure results in misfolded or underglycosylated protein accumulation in the endoplasmic reticulum. GRP78 overexpression was closely related to the magnitude of growth inhibition due to increasing concentrations of each VOC. The overexpression was found to be significant for concentrations 5 to 30 times higher than NOEC, indicating that, under our experimental conditions, GRP78 expression cannot be considered as a sensitive biomarker of exposure to environmental VOCs.

Patterns of metals and arsenic poisoning in Vibrio fischeri bacteria.

The Microtox bioassay was used to establish dose-response curves for some toxic elements in aqueous solutions, namely, Zn(II), Pb(II), Cu(II), Hg(II), Ag(I), Co(II), Cd(II), Cr(VI), As(V) and As(III). Experiments were carried out at either pH 6.0 or pH 7.0 to indicate that pH may influence the measured toxicity of some elements due to pH-related changes of their chemical speciation. EC20 values, which represent a measurable threshold of toxicity, were determined for each element and were found to rank as Pb(II)>Ag(I)>Hg(II) approximately Cu(II)>Zn(II)>As(V)>Cd(II) approximately Co(II)>As(III)>Cr(VI). These values were compared to the limit concentrations allowed in industrial wastewater according to the official regulations in Catalonia (Spain). It appears that the Microtox test is sensitive enough for detecting some of the tested elements with respect to official regulations of Catalonia (Spain) dealing with pollution control, with the exception of cadmium, mercury, arsenate, arsenite and chromate.

Expression of stress proteins in cultured HT29 human cell-line; a model for studying environmental aggression.

The current study was undertaken to investigate the expression of stress proteins (HSP) in cultured human HT29 cells submitted to stressing events under in vitro conditions. Heat shocks (45 degrees C, for 15-60 min) or cold shocks (+ 1 degree C for 4 hr) were found to modify cell growth (growth curves) and to enhance HSP expression. In most cases, changes in HSP expression are much more pronounced than changes in cell growth. Exposure to 8% ethanol for 15 min resulted in both growth inhibition and HSP overexpression. Propanol-1 was found to be more toxic since 5% concentration given for 15 min stops cell growth. 2.5% propanol-1 for 15 min induces a slight reduction of cell growth but a clear-cut overexpression of stress proteins. We conclude that expression of stress proteins, especially those of the HSP68/70 family, constitutes a more sensitive response than changes in growth rate in case of external aggression. This could make our model an interesting biological sensor to environmental physical or chemical pollutants.

Growth-related variation of alpha 2-adrenergic receptivity in the HT 29 adenocarcinoma cell-line from human colon.

The human colon adenocarcinoma cell-line HT 29 has been shown to possess functional alpha 2-adrenergic receptors. Here, [3H] clonidine was used as radioligand to study the evolution of alpha 2-adrenergic receptivity during the time course of HT 29 cell culture. Scatchard analysis of the saturation curves indicates that the number of [3H]clonidine binding sites increases throughout the 17 day culture period. The maximal number of alpha 2-adrenoceptors is found during the stationary phase of growth, when cell density is high and mitotic rate low. Moreover, the use of adrenaline and clonidine as alpha 2-adrenergic agonists reveals a relationship between the number of receptors and the intensity of the biological effect associated with their stimulation (inhibition of the VIP-induced cyclic AMP accumulation).

Pattern of stress protein expression in human lung cell-line A549 after short- or long-term exposure to cadmium.

Exposure to cadmium is associated with the development of pulmonary damage such as emphysema and lung cancer. This metal is also a powerful inducer of stress proteins in many biologic models. The present study was undertaken to evaluate whether an overexpression of the heat shock protein (hsp)72 stress protein, which indicates repair of damaged proteins, could be a sensitive and early biomarker of environmental pollution by Cd. In comparative studies, we examined the effects of exposure to Cd (as CdCl(2)) on the growth rate of the A549 pulmonary cell line, and (by Western blot analyses) on the induction of the hsp72 stress protein and metallothioneins (MTs). CdCl(2) exposure was studied for periods of 2 hr to 1 month. For short-term exposure (2-6 hr) to Cd concentrations higher than 50 microM, an overexpression of hsp72 appeared 6 hr later, suggesting that hsp72 might be considered an early biomarker of acute exposure to Cd. For exposures lasting more than 4 days, lower doses of Cd (0.1-10 microM) similar to levels encountered in occupational exposure induced a significant increase of the hsp72 level. Because the increase of hsp72 occurs for doses that did not affect cell proliferation, our work supports the idea that its overexpression might be used as a sensitive indicator of occupational exposure to Cd. However, increased resistance to Cd appeared in A549 cells exposed for 1 month and overexpression of hsp72 disappeared simultaneously. It is possible that, in vivo, cell adaptation also occurs throughout chronic exposure to Cd, with a decrease of hsp induction as a consequence. A dose-related increase of MTs was found after 4 days of exposure to Cd concentrations ranging from 0.1 to 10 microM without change of overexpression during chronic exposure, suggesting that MT expression could be a more constant indicator of Cd pollution. Because 0.1 microM Cd (11 microg/L) induces hsp72 expression, showing the presence of damaged proteins, our work suggests that the maximum allowable biologic exposure limit should be lowered.

alpha 2-Adrenoceptors in the HT 29 human colon adenocarcinoma cell line: characterization with [3H]clonidine; effects on cyclic AMP accumulation.

In the present work, [3H]clonidine was used to characterize alpha 2-adrenoceptors on the human adenocarcinoma cell line HT 29. The effects of alpha 2-adrenergic stimulation on cellular cyclic AMP levels were also investigated. The binding of [3H]clonidine on HT 29 cell membrane preparations was rapid and reversible. Scatchard analysis of the saturation curves indicated the existence of a single class of non-interacting sites with a KD of 1.29 +/- 0.07 nM and a Bmax of 114 +/- 7 fmol/mg of cell membrane protein. The binding sites for [3H]clonidine showed the required specificity for alpha 2-adrenoceptors. The potencies of alpha-adrenergic compounds to displace [3H]clonidine binding ranked as follows: yohimbine greater than phentolamine much greater than prazosin for antagonists and clonidine greater than epinephrine greater than norepinephrine greater than phenylephrine much greater than amidephrine for agonists. When tested on intact cells, epinephrine, norepinephrine and clonidine were found to counteract, in a dose-dependent manner, the increase of cyclic AMP triggered by vasoactive intestinal peptide (VIP). Such inhibitory effects were abolished by the addition of yohimbine but not of prazosin. The physiological amines were the most efficient agonists: both epinephrine and norepinephrine inhibited VIP-induced cyclic AMP accumulation by 50-55% with KD values of 50 nM and 300 nM respectively. Clonidine was a partial agonist only, provoking a weak (25-30%) inhibition of VIP-induced cyclic AMP accumulation even at high concentrations. These results indicate that, like normal colocytes, human colon adenocarcinoma cells HT 29 possess alpha 2-adrenoceptors, the stimulation of which is associated with an inhibition of cyclic AMP production.(ABSTRACT TRUNCATED AT 250 WORDS)

Toxicity of cadmium species on luminescent bacteria.

The toxicity of cadmium compounds against luminescent bacteria has been measured using the Microtox(R) toxicity bioassay and has been related to the cadmium species. Since the Microtox(R) test is carried out in NaCl (2%) and cadmium forms stable chloro complexes, NaNO(3) and NaClO(4) have been tested successfully as alternative to sodium chloride to provide the adequate osmotic protection of the bacteria. The influence of medium and ionic strength as well as different exposure times on EC(50) values has been evaluated.

Expression of stress proteins in cultured human cells as a sensitive indicator of metal toxicity.

Human cell lines cultured under standardized conditions are found to react after a wide variety of aggressive but sub-lethal treatments by expressing stress proteins, mainly of the HSP68, HSP70 and HSP90 families. The stress reaction is a repair mechanism which rapidly takes place after minute damages caused to cell structures. It was therefore proposed to develop a sensitive biomarker to monitor environmental pollution, especially related to metals, based on the evaluation of stress protein production. This was achieved by computer-assisted densitometric analysis of autoradiographies of electrophoretically separated (35)S-labelled proteins. The results indicate that our biological models consisting in HT29 and HepG2 cell-lines react to low concentrations of cadmium or nickel by a clear-cut increase of stress proteins expression. In most cases, this effect is much more significant and much more rapid to observe than changes in growth curves. It may constitute a reliable index of cell susceptibility to environmental aggressions.

Effects of melatonin on aluminium-induced neurobehavioral and neurochemical changes in aging rats.

This study aimed to investigate the potential protective effects of melatonin (Mel) against aluminium-induced neurodegenerative changes in aging Wistar rats (24-28months old). Herein, aluminium chloride (AlCl3) (50mg/kg BW/day) was administered by gavage, and melatonin (Mel) was co-administered to a group of Al-treated rats by an intra-peritoneal injection at a daily dose of 10mg/kg BW for four months. The findings revealed that aluminium administration induced a significant decrease in body weight associated with marked mortality for the old group of rats, which was more pronounced in old Al-treated rats. Behavioural alterations were assessed by 'open fields', 'elevated plus maze' and 'Radial 8-arms maze' tests. The results demonstrated that Mel co-administration alleviated neurobehavioral changes in both old and old Al-treated rats. Melatonin was noted to play a good neuroprotective role, reducing lipid peroxidation (TBARs), and enhancing enzymatic (SOD, CAT and GPx) activities in the brain organs of old control and old Al-treated rats. Mel treatment also reversed the decrease of AChE activity in the brain tissues, which was confirmed by histological sections. Overall, the results showed that Mel administration can induce beneficial effects for the treatment of Al-induced neurobehavioral and neurochemical changes in the central nervous system (CNS).

Chronic lithium administration triggers an over-expression of GRP94 stress protein isoforms in mouse liver.

Moderate doses of lithium were chronically administered to mice in order to verify whether the cytoprotective effects of lithium could be in part attributed to a molecular protection conferred by stress proteins/chaperones accumulation. In order to reach serum lithium levels within the common therapeutic values, mice were fed for 6 months on food pellets contained 1 g (L1 group) or 2 g (L2 group) lithium carbonate/kg, resulting in serum concentrations of 0.5 and 0.9 mM Li, respectively. Under these experimental conditions, no clinical side-effects were observed. Urea and creatinine concentrations in serum, lipids peroxidation level and activities of catalase, superoxide-dismutase and glutathione-peroxidase in liver and kidney were not significantly different from control values. Although the expression level of the constitutive HSP73 was not significantly modified, HSP72 was found to be down-regulated in kidney after 1 month. In liver, three protein bands were immunodetected by the anti-GRP94 antibody: 98 kDa and 96 kDa proteins corresponding to more or less glycosylated forms and/or phosphorylated forms of GRP94 and a 80 kDa protein probably being a cleavage product of GRP94. The 96 kDa and 80 kDa proteins were significantly up-regulated in liver of lithium-treated mice as compared to controls.

The effects of subchronic lithium administration in male Wistar mice on some biochemical parameters.

Lithium salts are efficiently used for treatment of psychiatric disorders. However, prolonged treatment frequently involves adverse side effects. In this study, effects of lithium carbonate administration on some biochemical parameters were studied in male mice. Lithium carbonate (20, 40, or 80 mg/kg body weight corresponding to 3.77, 7.54, or 15.08 mg Li element/kg body weight, respectively) was injected daily for 14 or 28 days. The following parameters were recorded: drinking water consumption, body weight, lithium and testosterone serum concentrations, activities of catalase (CAT), superoxide-dismutase (SOD), and glutathione-peroxidase (GPX), and level of lipid peroxidation (expressed as TBARS) in liver was performed. Lithium treatment, especially at the highest dose for 28 days, was found to induce weight gain and polydipsia and a significant decrease of plasma testosterone level. Lipid peroxidation level and activities of SOD and GPX were increased in liver, which suggests a perturbation of the antioxidative status. Our results indicate that subchronic exposure to lithium, which induces weight gain and polydipsia under our experimental conditions, also damages the male reproductive system and triggers an oxidative stress in the liver.