Dose-dependent toxicity profile and genotoxicity mechanism of lithium carbonate.

The increasing widespread use of lithium, which is preferred as an energy source in batteries produced for electric vehicles and in many electronic vehicles such as computers and mobile phones, has made it an important environmental pollutant. In this study, the toxicity profile of lithium carbonate (Li2CO3) was investigated with the Allium test, which is a bio-indicator test. Dose-related toxic effects were investigated using Li2CO3 at doses of 25 mg/L, 50 mg/L, and 100 mg/L. The toxicity profile was determined by examining physiological, cytotoxic, genotoxic, biochemical and anatomical effects. Physiological effects of Li2CO3 were determined by root length, injury rate, germination percentage and weight gain while cytotoxic effects were determined by mitotic index (MI) ratio and genotoxic effects were determined by micronucleus (MN) and chromosomal aberrations (CAs). The effect of Li2CO3 on antioxidant and oxidant dynamics was determined by examining glutathione (GSH), malondialdehyde (MDA), catalase (CAT) and superoxide dismutase (SOD) levels, and anatomical changes were investigated in the sections of root meristematic tissues. As a result, Li2CO3 exhibited a dose-dependent regression in germination-related parameters. This regression is directly related to the MI and 100 mg/L Li2CO3 reduced MI by 38% compared to the control group. MN and CAs were observed at high rates in the groups treated with Li2CO3. Fragments were found with the highest rate among CAs. Other damages were bridge, unequal distribution of chromatin, sticky chromosome, vagrant chromosome, irregular mitosis, reverse polarization and multipolar anaphase. The genotoxic effects were associated with Li2CO3-DNA interactions determined by molecular docking. The toxic effects of Li2CO3 are directly related to the deterioration of the antioxidant/oxidant balance in the cells. While MDA, an indicator of lipid peroxidation, increased by 59.1% in the group administered 100 mg/L Li2CO3, GSH, which has an important role in cell defense, decreased by 60.8%. Significant changes were also detected in the activities of SOD and CAT, two important enzymes in antioxidant defense, compared to the control. These toxic effects, which developed in the cells belonging to the lithium-treated groups, were also reflected in the tissue anatomy, and anatomical changes such as epidermis cell damage, cortex cell damage, flattened cell nucleus, thickening of the cortex cell wall and unclear vascular tissue were observed in the anatomical sections. The frequency of these changes also increased depending on the Li2CO3 dose. As a result, Li2CO3, which is one of the lithium compounds, and has become an important contaminant in the environment with increasing technological developments, caused a combined and versatile toxicity in Allium cepa L. meristematic cells, especially by causing deterioration in antioxidant/oxidant dynamics.

The association between testicular toxicity induced by Li2Co3 and protective effect of Ganoderma lucidum: Alteration of Bax & c-Kit genes expression.

Ganoderma lucidum has received a lot of attention recently due to its medicinal potential activities. The aim of this designed experiment was to evaluate the beneficial effects of Ganoderma lucidum extract against lithium carbonate induced testicular toxicity and related lesions in mice testis. For this purpose, lithium carbonate at a dose of 30 mg/kg, followed by 75, 150 mg/kg Ganoderma lucidum extract orally were administered for 35 days. The results were obtained from Ganoderma lucidum extract analysis prove contained a large amount of polysaccharides, triterpenoids and poly phenols based on spectrophotometric assay. Also, DPPH assay for Ganoderma lucidum extract showed high level of radical scavenging activity. The hematoxylin & eosin cross section from lithium carbonate treated group exhibited significant alterations in seminiferous tubules. Moreover, lithium carbonate induced oxidative stress via lipid peroxidation and generate MDA (P < 0.001). In addition, lithium carbonate initiated germ cells apoptosis via increase Bax expression (p < 0.001) and reduce germ cells differentiation through down-regulation of c-Kit expression (p < 0.05). Results from CASA showed that sperm parameters like count, motility and viability significantly decreased in lithium treated group (p < 0.001). It is clear that lithium carbonate induce severe damage on male reproductive system and histopathological damages via generation oxidative stress but supplementation with Ganoderma lucidum extract exhibited prevention effects and repaired induced damages.

Selenium prevents lithium accumulation and does not disturb basic microelement homeostasis in liver and kidney of rats exposed to lithium.

INTRODUCTION: Lithium has been used in medicine for almost seventy years. Besides beneficial effects, its therapy may cause serious side-effects, with kidney and liver being the organs most vulnerable to its harmful influence. Therefore, research on protective agents against lithium toxicity has been continuing for some time. OBJECTIVE: The aim of the present study is to evaluate the influence of additional selenium supplementation on lithium content, as well as homeostasis of the essential microelements iron, zinc, copper and manganese in kidney and liver of rats undergoing lithium exposure. MATERIAL AND METHODS: The study was performed on 4 groups of male Wistar rats (6 animals each) treated with: control - saline; Li-group - Li2CO3 at a dose of 2.7 mg Li/kg b.w.; Se-group - Na2SeO3 at a dose of 0.5 mg Se/kg b.w.; Li+Se-group - both Li2CO3 and Na2SeO3 at doses of 2.7 mg Li/kg b.w. and of 0.5 mg Se/kg b.w., respectively, in the form of water solutions by stomach tube, once a day for 3 weeks. The content of the studied elements in the organ samples was determined using flame atomic absorption spectroscopy (FAAS). RESULTS: Lithium administered alone caused a significant increase in its content in liver and kidney. Additional supplementation with selenium reversed these effects, and did not markedly affect other studied microelements compared to control. CONCLUSIONS: The obtained results suggest that selenium could be regarded as an adjuvant into lithium therapy. However, considering the limitations of the present study (the short duration, using only one dose and form of selenium) the continuation of the research seems to be necessary to clarify the influence of selenium supplementation on basic microelements and lithium accumulation in organs during lithium exposure.

Lithium disturbs homeostasis of essential microelements in erythrocytes of rats: Selenium as a protective agent?

BACKGROUND: Selenium is an essential element which shows protective properties against diverse harmful factors. Lithium compounds are widely used in medicine, but, in spite of undoubted beneficial effects, treatment with these compounds may lead to severe side effects, including renal, gastrointestinal, neurological, endocrine and metabolic disorders. This study was aimed at evaluating the influence of selenium and/or lithium on lithium, iron, zinc and copper content in rats' erythrocytes as well as estimate the action of additional selenium on lithium exposure effects. METHODS: The experiment was performed on four groups of rats (six animals each): control - received saline; Li - received 2.7mg Li/kg b.w. as lithium carbonate; Se - received 0.5mg Se/kg b.w. as sodium selenite; Se+Li - received simultaneously 0.5mg Se/kg b.w. and 2.7mg Li/kg b.w. (sodium selenite and lithium carbonate). The administration was performed for three weeks, once a day by stomach tube, in form of water solutions. In erythrocytes the content of lithium, iron, zinc and copper was determined using flame atomic absorption spectroscopy. RESULTS: Lithium treatment insignificantly disturbed iron and zinc homeostasis as well as markedly increased lithium accumulation and copper content in rat erythrocytes. Selenium coadministration reversed those effects. CONCLUSIONS: The beneficial effect of selenium on disturbances of studied microelements homeostasis as well as on preventing lithium accumulation in erythrocytes in Li receiving animals allows suggesting that further research on selenium application as an adjuvant in lithium therapy is worth carrying on.

A new insight on the role of zinc in the regulation of altered thyroid functions during lithium treatment.

BACKGROUND: Lithium salts are widely used for the treatment of mental disorders but cause thyroid dysfunctions while zinc is an essential trace element and is required for a broad range of biological activities. The present study was designed to explore the potential of zinc in regulating 131I biokinetics and thyroid functions following lithium therapy. METHODS: To carry out the investigations, 40 female sprague dawley rats weighing 110-140g were segregated into four groups viz. Group I animals served as untreated controls, group II animals were given lithium (Li2CO31.1 g/kg diet), group III animals were supplemented with zinc (227 mg ZnSO4/L drinking water) and animals in group IV were given a combined treatment of lithium and zinc. The treatments were given for durations of 1, 2 and 4 months. RESULTS: Following intraperitoneal administration of 0.37 MBq carrier- free-131I, a significant depression in the thyroidal 131I uptake both at 2 and 24 hrs was observed following lithium treatment for all the durations which however was brought to within normal levels following zinc supplementation. Lithium treatment caused a significant elevation in the thyroidal biological half lives of 131I which was appreciably attenuated following 2 and 4 months of zinc supplementation. Lithium administration for 2 and 4 months significantly decreased serum T3 and T4 levels which however were increased following zinc supplementation. Lithium treatment for 4 months caused a significant decrease in the thyroidal activities of Na+ K+ ATPase and monoamine oxidase which were brought to near normal levels by zinc. Further, lithium treatment for 4 months raised thyroidal levels of lipid peroxidation and catalase which however were normalized by zinc supplementation. On the contrary, thyroidal levels of reduced glutathione and glutathione S transferase decreased significantly following 2 and 4 months of lithium treatment but were significantly increased following zinc treatment. CONCLUSIONS: The present study concludes that zinc supplementation is helpful in attenuating the adverse effects caused by lithium on thyroid functions and can effectively regulate the biokinetics of 131I.

Dietary calcium blocks lithium toxicity in hamsters without affecting circadian rhythms.

Lithium can be toxic to rodents at plasma concentrations (0.6-1.2 mmol/L) that also phase delay circadian rhythms. In hamsters, raising the concentration of calcium in the diet from 0.1%-3% reduced weight loss and polydipsia caused by 0.4% lithium carbonate. Calcium ingestion did not affect plasma lithium concentration or the phase of the circadian wheel-running rhythm in lithium-treated animals. Calcium ingestion did not alter weight gain, salt or water intake, or circadian rhythms in hamsters not receiving lithium. Dietary calcium supplementation may prevent some toxic effects of lithium without interfering with other central nervous system actions.