Towards a Unified Understanding of Lithium Action in Basic Biology and its Significance for Applied Biology

Ion Selectivity in the ENaC/DEG Family: A Systematic Review with Supporting Analysis

The Epithelial Sodium Channel/Degenerin (ENaC/DEG) family is a superfamily of sodium-selective channels that play diverse and important physiological roles in a wide variety of animal species. Despite their differences, they share a high homology in the pore region in which the ion discrimination takes place. Although ion selectivity has been studied for decades, the mechanisms underlying this selectivity for trimeric channels, and particularly for the ENaC/DEG family, are still poorly understood. This systematic review follows PRISMA guidelines and aims to determine the main components that govern ion selectivity in the ENaC/DEG family. In total, 27 papers from three online databases were included according to specific exclusion and inclusion criteria. It was found that the G/SxS selectivity filter (glycine/serine, non-conserved residue, serine) and other well conserved residues play a crucial role in ion selectivity. Depending on the ion type, residues with different properties are involved in ion permeability. For lithium against sodium, aromatic residues upstream of the selectivity filter seem to be important, whereas for sodium against potassium, negatively charged residues downstream of the selectivity filter seem to be important. This review provides new perspectives for further studies to unravel the mechanisms of ion selectivity.

Triphasic Waves: Historical Overview of an Unresolved Mystery

SUMMARY

Triphasic waves are a fascinating and mysterious EEG feature. We now have to accept that, at times, epileptiform discharges may have a blunted "triphasic morphology," and that there may be great difficulty in distinguishing between these often similar forms. The aim of this review was to describe the evolution in our understanding of triphasic waves that has occurred regarding the pathophysiology of triphasic waves, their most frequent causes, and the diagnostic difficulties involved in interpretation and differentiation from nonconvulsive status epilepticus.

Therapeutic lithium alters polar head-group region of lipid bilayer and prevents lipid peroxidation in forebrain cortex of sleep-deprived rats

Lithium is regarded as a unique therapeutic agent for the management of bipolar disorder (BD). In efforts to explain the favourable effects of lithium in BD, a wide range of mechanisms was suggested. Among those, the effect of clinically relevant concentrations of lithium on the plasma membrane was extensively studied. However, the biophysical properties of brain membranes isolated from experimental animals exposed to acute, short-term and chronic lithium have not been performed to-date. In this study, we compared the biophysical parameters and level of lipid peroxidation in membranes isolated from forebrain cortex (FBC) of therapeutic lithium-treated and/or sleep-deprived rats. Lithium interaction with FBC membranes was characterized by appropriate fluorescent probes. DPH (1,6-diphenyl-1,3,5-hexatriene) and TMA-DPH (1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene p-toluenesulphonate) were used for characterization of the hydrophobic lipid core and Laurdan (6-dodecanoyl-2-dimethylaminonaphthalene) for the membrane-water interface. Lipid peroxidation was determined by immunoblot analysis of 4-HNE-(4-hydroxynonenal)-protein adducts. The organization of polar head-group region of FBC membranes, measured by Laurdan generalized polarization, was substantially altered by sleep deprivation and augmented by lithium treatment. Hydrophobic membrane interior characterized by steady-state anisotropy of DPH and TMA-DPH fluorescence was unchanged. Chronic lithium had a protective effect against peroxidative damage of membrane lipids in FBC. In summary, lithium administration at a therapeutic level and/or sleep deprivation as an animal model of mania resulted in changes in rat FBC membrane properties.

The Upcoming 6Li Isotope Requirements Might Be Supplied by a Microalgal Enrichment Process

Lithium isotopes are essential for nuclear energy, but new enrichment methods are required. In this study, we considered biotechnology as a possibility. We assessed the Li fractionation capabilities of three Chlorophyte strains: Chlamydomonas reinhardtii, Tetraselmis mediterranea, and a freshwater Chlorophyte, Desmodesmus sp. These species were cultured in Li containing media and were analysed just after inoculation and after 3, 12, and 27 days. Li mass was determined using a Inductively Coupled Plasma Mass Spectrometer, and the isotope compositions were measured on a Thermo Element XR Inductively Coupled Plasma Mass Spectrometer. The maximum Li capture was observed at day 27 with C. reinhardtii (31.66 µg/g). Desmodesmus sp. reached the greatest Li fractionation, (δ⁶ = 85.4‰). All strains fractionated preferentially towards ⁶Li. More studies are required to find fitter species and to establish the optimal conditions for Li capture and fractionation. Nevertheless, this is the first step for a microalgal nuclear biotechnology.

Trinuclear Calcium Site in the C2 Domain of PKCα/γ Is Prone to Lithium Attack

Lithium (Li⁺) is the first-line therapy for bipolar disorder and a candidate drug for various diseases such as amyotrophic lateral sclerosis, multiple sclerosis, and stroke. Despite being the captivating subject of many studies, the mechanism of lithium's therapeutic action remains unclear. To date, it has been shown that Li⁺ competes with Mg²⁺ and Na⁺ to normalize the activity of inositol and neurotransmitter-related signaling proteins, respectively. Furthermore, Li⁺ may co-bind with Mg²⁺-loaded adenosine or guanosine triphosphate to alter the complex's susceptibility to hydrolysis and mediate cellular signaling. Bipolar disorder patients exhibit abnormally high cytosolic Ca²⁺ levels and protein kinase C (PKC) hyperactivity that can be downregulated by long-term Li⁺ treatment. However, the possibility that monovalent Li⁺ could displace the bulkier divalent Ca²⁺ and inhibit PKC activity has not been considered. Here, using density functional theory calculations combined with continuum dielectric methods, we show that Li⁺ may displace the native dication from the positively charged trinuclear site in the C2 domain of cytosolic PKCα/γ. This would affect the membrane-docking ability of cytosolic PKCα/γ and reduce the abnormally high membrane-associated active PKCα/γ levels, thus downregulating the PKC hyperactivity found in bipolar patients.

FROZEN! Intracellular multi-electrolyte analysis measures millimolar lithium in mammalian cells

Lithium salts are commonly used as medication for Bipolar Disorder (BD) and depression. However, there are limited methods to quantify intracellular lithium. Most methods to analyze intracellular electrolytes require tedious sample processing, specialized and often expensive machinery, sometimes involving harmful chemicals, and a bulk amount of the sample. In this work, we report a novel method (FROZEN!) based on cell isolation (from the surrounding medium) through rapid de-ionized water cleaning, followed by flash freezing for preservation. SKOV3 cells were cultured in normal medium and a medium containing 1.0 mM lithium. Lithium and other intracellular electrolytes in the isolated and preserved cells were simultaneously analyzed with laser-induced breakdown spectroscopy (LIBS) and X-ray fluorescence spectroscopy (XRF). Key electrolytes such as sodium, potassium, and magnesium, along with lithium, were detectable at the single-cell level. We found that cells cultured in the lithium medium have an intracellular lithium concentration of 0.5 mM. Concurrently, the intracellular concentrations of other positively charged electrolytes (sodium, potassium, and magnesium) were reduced by the presence of lithium. FROZEN! will greatly facilitate research in intracellular electrolyte balance during drug treatment, or other physiological stresses. In particular, the cell isolation and preservation steps can be easily performed by many laboratories worldwide, after which the samples are sent to an analytical laboratory for electrolyte analysis.

Translational evidence for lithium-induced brain plasticity and neuroprotection in the treatment of neuropsychiatric disorders

Increasing evidence indicates lithium (Li+) efficacy in neuropsychiatry, pointing to overlapping mechanisms that occur within distinct neuronal populations. In fact, the same pathway depending on which circuitry operates may fall in the psychiatric and/or neurological domains. Li+ restores both neurotransmission and brain structure unveiling that psychiatric and neurological disorders share common dysfunctional molecular and morphological mechanisms, which may involve distinct brain circuitries. Here an overview is provided concerning the therapeutic/neuroprotective effects of Li+ in different neuropsychiatric disorders to highlight common molecular mechanisms through which Li+ produces its mood-stabilizing effects and to what extent these overlap with plasticity in distinct brain circuitries. Li+ mood-stabilizing effects are evident in typical bipolar disorder (BD) characterized by a cyclic course of mania or hypomania followed by depressive episodes, while its efficacy is weaker in the opposite pattern. We focus here on neural adaptations that may underlie psychostimulant-induced psychotic development and to dissect, through the sensitization process, which features are shared in BD and other psychiatric disorders, including schizophrenia. The multiple functions of Li+ highlighted here prove its exceptional pharmacology, which may help to elucidate its mechanisms of action. These may serve as a guide toward a multi-drug strategy. We propose that the onset of sensitization in a specific BD subtype may predict the therapeutic efficacy of Li+. This model may help to infer in BD which molecular mechanisms are relevant to the therapeutic efficacy of Li+.

The influence of Li+ ions on pepsin and trypsin activity in vitro

BACKGROUND

The paper presents a study on the influence of different lithium carbonate and lithium citrate concentration on proteolytic enzymes, namely pepsin and trypsin, in vitro. Lithium can directly affect enzyme activity. Its influence on many bodily functions in both ill and healthy people has been proven.

METHODS

To assess the influence of Li⁺ ions concentration and the substrate/enzyme ratio on pepsin and trypsin activity in vitro, 60 factorial experiments were conducted (each repeated 30 times).

MAIN FINDINGS

For both enzymes, statistically significant changes in their activity under the influence of lihium carbonate and lithium citrate were observed. The biggest increase in enzyme activity reached even 198.6 % and the largest decrease in enzyme activity reached about 50 %.

CONCLUSIONS

The study shows that both organic and inorganic forms of lithium salts cause changes in the activity of digestive enzymes. Different concentrations of lithium carbonate and lithium citrate stimulate or inhibit the activity of trypsin and pepsin.

Autism-associated SHANK3 mutations impair maturation of neuromuscular junctions and striated muscles

Heterozygous mutations of the gene encoding the postsynaptic protein SHANK3 are associated with syndromic forms of autism spectrum disorders (ASDs). One of the earliest clinical symptoms in SHANK3-associated ASD is neonatal skeletal muscle hypotonia. This symptom can be critical for the early diagnosis of affected children; however, the mechanism mediating hypotonia in ASD is not completely understood. Here, we used a combination of patient-derived human induced pluripotent stem cells (hiPSCs), Shank3Δ11(-/-) mice, and Phelan-McDermid syndrome (PMDS) muscle biopsies from patients of different ages to analyze the role of SHANK3 on motor unit development. Our results suggest that the hypotonia in SHANK3 deficiency might be caused by dysfunctions in all elements of the voluntary motor system: motoneurons, neuromuscular junctions (NMJs), and striated muscles. We found that SHANK3 localizes in Z-discs in the skeletal muscle sarcomere and co-immunoprecipitates with α-ACTININ. SHANK3 deficiency lead to shortened Z-discs and severe impairment of acetylcholine receptor clustering in hiPSC-derived myotubes and in muscle from Shank3Δ11(-/-) mice and patients with PMDS, indicating a crucial role for SHANK3 in the maturation of NMJs and striated muscle. Functional motor defects in Shank3Δ11(-/-) mice could be rescued with the troponin activator Tirasemtiv that sensitizes muscle fibers to calcium. Our observations give insight into the function of SHANK3 besides the central nervous system and imply potential treatment strategies for SHANK3-associated ASD.

Lithium Chloride Exerts Differential Effects on Dentinogenesis and Osteogenesis in Primary Pulp Cultures

Wnt/β-catenin signaling is known to play essential roles in odontoblast differentiation and reparative dentin formation. Various Wnt activators including LiCl have been increasingly studied for their effectiveness to induce repair of the dentin-pulp complex. LiCl is a simple salt thought to activate Wnt/β-catenin signaling by inhibiting GSK3β. Previous in vitro and in vivo studies showed that LiCl increased odontoblast differentiation and enhanced reparative dentin formation. However, the underlying molecular and cellular mechanisms by which LiCl regulates odontoblast and osteoblast differentiation during reparative dentinogenesis are not well-understood. Our in vitro studies show that exposure of early dental pulp progenitors to LiCl increased the survival and the pool of αSMA+ progenitors, leading to enhanced odontoblast and osteoblast differentiation. The positive effects of LiCl in the differentiation of osteoblasts and odontoblasts from αSMA+ progenitors are mediated by Wnt/β-catenin signaling. Our results also showed that continuous and late exposure of dental pulp cells to LiCl increased the expression of odontoblast markers through Wnt/β-catenin signaling, and the number of odontoblasts expressing DMP1-Cherry and DSPP-Cerulean transgenes. However, unlike the early treatment, both continuous and late treatments decreased the expression of Bsp and the expression of BSP-GFPtpz transgene. These observations suggest that prolonged treatment with LiCl in more mature cells of the dental pulp has an inhibitory effect on osteoblast differentiation. The inhibitory effects of LiCl on osteogenesis and Bsp were not mediated through Wnt/β-catenin signaling. These observations suggest that the effects of LiCl, and GSK3β antagonists on reparative dentinogenesis involve multiple pathways and are not specific to Wnt/β-catenin signaling.

[Lithium in the psychopharmacology of affective disorders and mechanisms of its effects on cellular physiology]

However, despite successful use of lithium in the treatment of affective disorders for almost 40 years, the mechanisms of its therapeutic action are still poorly understood. This review presents and summarizes the current literature about the use of lithium in treatment of affective disorders, as well as its effects on cellular physiology, with a separate description of the effect of this ion on the functioning of nerve tissue and ion-molecular mechanisms.

Inorganic ions in the skin: Allies or enemies?

Skin constitutes a barrier protecting the organism against physical and chemical factors. Therefore, it is constantly exposed to the xenobiotics, including inorganic ions that are ubiquitous in the environment. Some of them play important roles in homeostasis and regulatory functions of the body, also in the skin, while others can be considered dangerous. Many authors have shown that inorganic ions could penetrate inside the skin and possibly induce local effects. In this review, we give an account of the current knowledge on the effects of skin exposure to inorganic ions. Beneficial effects on skin conditions related to the use of thermal spring waters are discussed together with the application of aluminium in underarm hygiene products and silver salts in treatment of difficult wounds. Finally, the potential consequences of dermal exposure to topical sensitizers and harmful heavy ions including radionuclides are discussed.

How safe are the new green energy resources for marine wildlife? The case of lithium

Considering the increasing use of Lithium (Li) and the necessity to fulfil this demand, labile Li occurrence in the environment will be enhanced. Thus, additional research is needed regarding the presence of this element in marine environment and its potential toxic impacts towards inhabiting wildlife. The aim of the present study was to evaluate Li toxicity based on the exposure of Mytilus galloprovincialis to this metal, assessing the biochemical changes related with mussels' metabolism, oxidative stress and neurotoxicity. For this, organisms were exposed to different Li concentrations (100, 250, 750 μg/L) for 28 days. The results obtained clearly demonstrated that Li lead to mussels' metabolism depression. The present study also revealed that, especially at the highest concentrations, antioxidant and biotransformation enzymes were not activated, leading to the occurrence of lipid peroxidation and loss of redox homeostasis, with increased content in oxidized glutathione in comparison to the reduced form. Furthermore, after 28 days, higher Li exposure concentrations induced neurotoxic effects in mussels, with a decrease in acetylcholinesterase enzyme activity. The responses observed were closely related with Li concentrations in mussels' tissues, which were more pronounced at higher exposure concentrations. Such results highlight the potential toxic effects of Li to marine species, which may even be higher under predicted climate changes and/or in the presence of other pollutants.

Mitochondria under the spotlight: On the implications of mitochondrial dysfunction and its connectivity to neuropsychiatric disorders

Neuropsychiatric disorders (NPDs) such as bipolar disorder (BD), schizophrenia (SZ) and mood disorder (MD) are hard to manage due to overlapping symptoms and lack of biomarkers. Risk alleles of BD/SZ/MD are emerging, with evidence suggesting mitochondrial (mt) dysfunction as a critical factor for disease onset and progression. Mood stabilizing treatments for these disorders are scarce, revealing the need for biomarker discovery and artificial intelligence approaches to design synthetically accessible novel therapeutics. Here, we show mt involvement in NPDs by associating 245 mt proteins to BD/SZ/MD, with 7 common players in these disease categories. Analysis of over 650 publications suggests that 245 NPD-linked mt proteins are associated with 800 other mt proteins, with mt impairment likely to rewire these interactions. High dosage of mood stabilizers is known to alleviate manic episodes, but which compounds target mt pathways is another gap in the field that we address through mood stabilizer-gene interaction analysis of 37 prescriptions and over-the-counter psychotropic treatments, which we have refined to 15 mood-stabilizing agents. We show 26 of the 245 NPD-linked mt proteins are uniquely or commonly targeted by one or more of these mood stabilizers. Further, induced pluripotent stem cell-derived patient neurons and three-dimensional human brain organoids as reliable BD/SZ/MD models are outlined, along with multiomics methods and machine learning-based decision making tools for biomarker discovery, which remains a bottleneck for precision psychiatry medicine.

Unraveling the Hidden Role of the Counteranion in "Cation in a Cage" Systems

The current work showcases general principles at play in systems consisting of cations present inside molecular cages. Such systems, relevant to chemistry and biology, have been carefully investigated by computational methods. The important Ge(II)-encapsulating cage systems have been studied first. The very fact that such compounds exist appears highly unlikely, given the highly reactive nature of the Ge(II) dication. Our studies reveal what really occurs in solution when such complexes are formed: the Ge(II) dications are actually present as [Ge-X]⁺ (where X is the "non-coordinating" counterion employed in such systems) during entry and subsequent existence at the center of the cage. Hence, what is actually present is a "pseudomonocation". Interestingly, such pseudomonocation-encapsulated cages are seen to be equally relevant in systems of biological importance, such as for dicationic s block-based ionophores. In explaining such cases, the concept of "isoionicity" is introduced, demonstrating that the counterion-coordinated dications are isoionic with a monocation, such as Li(I), isolated in the same ionophore.

Transferable interactions of Li+ and Mg2+ ions in polarizable models

Therapeutic implications of Li⁺, in many cases, stem from its ability to inhibit certain Mg²⁺-dependent enzymes, where it interacts with or substitutes for Mg²⁺. The underlying details of its action are, however, unknown. Molecular simulations can provide insights, but their reliability depends on how well they describe relative interactions of Li⁺ and Mg²⁺ with water and other biochemical groups. Here, we explore, benchmark, and recommend improvements to two simulation approaches: the one that employs an all-atom polarizable molecular mechanics (MM) model and the other that uses a hybrid quantum and MM implementation of the quasi-chemical theory (QCT). The strength of the former is that it describes thermal motions explicitly and that of the latter is that it derives local contributions from electron densities. Reference data are taken from the experiment, and also obtained systematically from CCSD(T) theory, followed by a benchmarked vdW-inclusive density functional theory. We find that the QCT model predicts relative hydration energies and structures in agreement with the experiment and without the need for additional parameterization. This implies that accurate descriptions of local interactions are essential. Consistent with this observation, recalibration of local interactions in the MM model, which reduces errors from 10.0 kcal/mol to 1.4 kcal/mol, also fixes aqueous phase properties. Finally, we show that ion-ligand transferability errors in the MM model can be reduced significantly from 10.3 kcal/mol to 1.2 kcal/mol by correcting the ligand's polarization term and by introducing Lennard-Jones cross-terms. In general, this work sets up systematic approaches to evaluate and improve molecular models of ions binding to proteins.

Accumulation of Lithium in the Hippocampus of Patients With Bipolar Disorder: A Lithium-7 Magnetic Resonance Imaging Study at 7 Tesla

BACKGROUND

Lithium (Li) is a first-line treatment for bipolar disorder (BD). To study its cerebral distribution and association with plasma concentrations, we used ⁷Li magnetic resonance imaging at 7T in euthymic patients with BD treated with Li carbonate for at least 2 years.

METHODS

Three-dimensional ⁷Li magnetic resonance imaging scans (N = 21) were acquired with an ultra-short echo-time sequence using a non-Cartesian k-space sampling scheme. Lithium concentrations ([Li]) were estimated using a phantom replacement approach accounting for differential T₁ and T₂ relaxation effects. In addition to the determination of mean regional [Li] from 7 broad anatomical areas, voxel- and parcellation-based group analyses were conducted for the first time for ⁷Li magnetic resonance imaging.

RESULTS

Using unprecedented spatial sensitivity and specificity, we were able to confirm the heterogeneity of the brain Li distribution and its interindividual variability, as well as the strong correlation between plasma and average brain [Li] ([Li]_B ≈ 0.40 × [Li]_P, R = .74). Remarkably, our statistical analysis led to the identification of a well-defined and significant cluster corresponding closely to the left hippocampus for which high Li content was displayed consistently across our cohort.

CONCLUSIONS

This observation could be of interest considering 1) the major role of the hippocampus in emotion processing and regulation, 2) the consistent atrophy of the hippocampus in untreated patients with BD, and 3) the normalization effect of Li on gray matter volumes. This study paves the way for the elucidation of the relationship between Li cerebral distribution and its therapeutic response, notably in newly diagnosed patients with BD.

Solving the crisis in psychopharmacological research: Cellular-membrane(s) pharmacology to the rescue?

There is an urgent need for the introduction of novel and better (i.e., improved risk-benefit profile) compounds for the treatment of major psychiatric disorders, in particular mood and psychotic disorders. However, despite increased societal awareness and a rising public and professional demand for such agents from patients and physicians, the pharmaceutical industry continues to close down its psychopharmacology research facilities in reaction to the lack of success with the search for new psychotropics. It is high time to stop this untoward trend and explore "new" lines of investigation to solve the current crisis in psychopharmacological research. In line with the prevailing molecular view in drug research in general, also in psychopharmacology mechanistic explanations for drug effects are "traditionally" looked for at the level of molecular targets, like receptors and transporters. Also, more recent approaches, although using so-called systems- and function-based approaches to model the multidimensional characteristics of psychiatric disorders and psychotropic drug action, still emphasize this search strategy for new therapeutic leads by identification of single molecules or molecular pathways. This "psychomolecular gaze" overlooks and disregards the fact that psychotropic agents usually are highly hydrophobic and amphipathic/amphiphilic agents that, in addition to their interaction with membrane-bound proteins in the form of e.g. receptors or transporters, also interact strongly with the lipid component of cellular membranes. Here we suggest to develop a program of systematic, whole-cell level based, investigation into the role of these physical-chemical cellular membrane interactions in the therapeutic action of known psychotherapeutics. This complementary yet conceptually different approach, in our opinion, will complement drug development in psychopharmacology and thereby assist in overcoming the current crisis. In this way the "old" physical theory of drug action, which antedates the current, primary molecular, paradigm may offer "new" options for lead discovery in psychopharmacological research.

Lithium influences whole-organism metabolic rate in Drosophila subobscura

Lithium is widely used to treat bipolar disorder. However, the efficacy and vulnerability as to its side effects are known to differ. Although the specific biochemical mechanism of action is still elusive, lithium may influence mitochondrial function, and consequently, metabolism. Lithium exposure in this study was conducted on a unique set of mito-nuclear introgression lines of Drosophila subobscura to disentangle the independent effects of mitochondrial DNA (mtDNA) against a common nuclear DNA background. The study addressed three issues: (a) whether lithium has a dose-dependent effect on whole-organism metabolic rate, (b) whether mtDNA haplotypes show divergent metabolic efficiency measured by metabolic rate to lithium exposure and (c) whether lithium influences the whole-organism metabolic rate across sexes. The results confirm that lithium influenced the whole-organism metabolic rate, showing a subtle balance between efficacy and adverse effects within a narrow dose range. In addition, lithium exposure was found to influence metabolism differently based on mtDNA haplotypes and sex. This preliminary research may have a range of biological implications for the role of mitochondrial variability in psychiatric disease and treatment by contributing to the understanding and predicting of the lithium treatment response and risk for toxic side effects.

Haploinsufficiency of Cyfip2 Causes Lithium-Responsive Prefrontal Dysfunction

OBJECTIVE

Genetic variants of the cytoplasmic FMR1-interacting protein 2 (CYFIP2) encoding an actin-regulatory protein are associated with brain disorders, including intellectual disability and epilepsy. However, specific in vivo neuronal defects and potential treatments for CYFIP2-associated brain disorders remain largely unknown. Here, we characterized Cyfip2 heterozygous (Cyfip2^+/- ) mice to understand their neurobehavioral phenotypes and the underlying pathological mechanisms. Furthermore, we examined a potential treatment for such phenotypes of the Cyfip2^+/- mice and specified a neuronal function mediating its efficacy.

METHODS

We performed behavioral analyses of Cyfip2^+/- mice. We combined molecular, ultrastructural, and in vitro and in vivo electrophysiological analyses of Cyfip2^+/- prefrontal neurons. We also selectively reduced CYFIP2 in the prefrontal cortex (PFC) of mice with virus injections.

RESULTS

Adult Cyfip2^+/- mice exhibited lithium-responsive abnormal behaviors. We found increased filamentous actin, enlarged dendritic spines, and enhanced excitatory synaptic transmission and excitability in the adult Cyfip2^+/- PFC that was restricted to layer 5 (L5) neurons. Consistently, adult Cyfip2^+/- mice showed increased seizure susceptibility and auditory steady-state responses from the cortical electroencephalographic recordings. Among the identified prefrontal defects, lithium selectively normalized the hyperexcitability of Cyfip2^+/- L5 neurons. RNA sequencing revealed reduced expression of potassium channel genes in the adult Cyfip2^+/- PFC. Virus-mediated reduction of CYFIP2 in the PFC was sufficient to induce L5 hyperexcitability and lithium-responsive abnormal behavior.

INTERPRETATION

These results suggest that L5-specific prefrontal dysfunction, especially hyperexcitability, underlies both the pathophysiology and the lithium-mediated amelioration of neurobehavioral phenotypes in adult Cyfip2^+/- mice, which can be implicated in CYFIP2-associated brain disorders. ANN NEUROL 2020;88:526-543.

Clinical Risk Factors for Therapeutic Lithium-Associated Electrocardiographic Changes in Patients With Bipolar Disorder

PURPOSE/BACKGROUND

Lithium, a common medication used in bipolar disorder treatment, can exert an inhibitory effect on sodium and potassium channels and potentially cause cardiac electrical conduction disturbance and corrected QT (QTc) prolongation. This study aimed to examine whether lithium at therapeutic levels can change electrocardiographic parameters in different groups of patients with bipolar disorder and to identify the potential clinical risk factors.

METHODS/PROCEDURES

Standard 12-lead electrocardiogram data before and after lithium treatment in bipolar disorder patients after at least 2-week dropout of psychotropic medications were analyzed.

FINDINGS/RESULTS

A total of 39 patients with bipolar disorder receiving lithium treatment were enrolled. Nineteen patients (48.7%) exhibited increased from P wave beginning to QRS complex beginning intervals after lithium treatment (mean serum level, 0.653 ± 0.247 mmol/L). Twenty-four patients (61.5%) exhibited increased a combination of Q, R, and S waves complex durations and increased QTc intervals. Twenty-three patients (59.0%) exhibited increased corrected JT (JTc) intervals. The patient group with increased QTc or JTc intervals exhibited a higher mean systolic blood pressure than did the patient group without increased QTc (134.7 ± 19.2 mm Hg vs 115.7 ± 11.8 mm Hg, P = 0.020) or JTc intervals (134.4 ± 19.6 mm Hg vs 117.6 ± 13.3 mm Hg, P = 0.054), respectively. Biochemical and hemodynamic parameters were comparable between patients with and without increased a combination of Q, R, and S waves complex durations or from P wave beginning to QRS complex beginning intervals.

IMPLICATIONS/CONCLUSIONS

Elevated systolic blood pressure may be the risk factor for the ventricular conduction delay in bipolar disorder patients receiving lithium at therapeutic levels.

Lithium Stabilizes the Mood of Bipolar Patients by Depolarizing the Neuronal Membrane Via Quantum Tunneling through the Sodium Channels

Objective

Lithium is used as first line in treating bipolar patients to stabilize their mood. However, the exact mechanism of lithium is not yet established. One of the proposed mechanisms is that lithium depolarizes the hyperpolarized neuronal membrane of bipolar patients bringing it back to the normal potential. On the other hand, the only way that lithium causes significant therapeutic depolarization is to have a membrane conductance that must be at least an order of magnitude higher than that for sodium but this is not achieved since both; lithium and sodium have the same conductance because the membrane channels are selective for them approximately by the same degree. So, this study aimed to explain how lithium could achieve higher conductance than sodium.

Methods

The idea of quantum tunneling through closed channels was used in a way to calculate the tunneling probability and the quantum conductance for lithium ions.

Results

It was found that lithium could achieve higher conductance than sodium because it has a smaller mass than sodium making lithium to have higher probability of tunneling and consequently higher conductance through channels and membrane.

Conclusion

Lithium tunneling model provides a reasonable explanation for the therapeutic depolarization effect of lithium. This model is experimentally testable to prove the tunneling effect of ions through the closed channels and to show the variations of quantum conductance between ions according to their mass.

Low-dose lithium feeding increases the SERCA2a-to-phospholamban ratio, improving SERCA function in murine left ventricles

NEW FINDINGS

What is the central question of this study? Inhibition of glycogen synthase kinase-3 (GSK3) has been shown to improve cardiac SERCA2a function. Lithium can inhibit GSK3, but therapeutic doses used in treating bipolar disorder can have toxic effects. It has not been determined whether subtherapeutic doses of lithium can improve cardiac SERCA function. What is the main finding and its importance? Using left ventricles from wild-type mice, we found that subtherapeutic lithium feeding for 6 weeks decreased GSK3 activity and increased cardiac SERCA function compared with control-fed mice. These findings warrant the investigation of low-dose lithium feeding in preclinical models of cardiomyopathy and heart failure to determine the therapeutic benefit of GSK3 inhibition.

ABSTRACT

The sarco(endo)plasmic reticulum Ca²⁺ -ATPase (SERCA) pump is responsible for regulating calcium (Ca²⁺ ) within myocytes, with SERCA2a being the dominant isoform in cardiomyocytes. Its inhibitor, phospholamban (PLN), acts by decreasing the affinity of SERCA for Ca²⁺ . Changes in the SERCA2a:PLN ratio can cause Ca²⁺ dysregulation often seen in patients with dilated cardiomyopathy and heart failure. The enzyme glycogen synthase kinase-3 (GSK3) is known to downregulate SERCA function by decreasing the SERCA2a:PLN ratio. In this study, we sought to determine whether feeding mice low-dose lithium, a natural GSK3 inhibitor, would improve left ventricular SERCA function by altering the SERCA2a:PLN ratio. To this end, male wild-type C57BL/6J mice were fed low-dose lithium via drinking water (10 mg kg^-1  day^-1 LiCl for 6 weeks) and left ventricles were harvested. GSK3 activity was significantly reduced in LiCl-fed versus control-fed mice. The apparent affinity of SERCA for Ca²⁺ was also increased (pCa₅₀ ; control, 6.09 ± 0.03 versus LiCl, 6.26 ± 0.04, P < 0.0001) along with a 2.0-fold increase in SERCA2a:PLN ratio in LiCl-fed versus control-fed mice. These findings suggest that low-dose lithium supplementation can improve SERCA function by increasing the SERCA2a:PLN ratio. Future studies in murine preclinical models will determine whether GSK3 inhibition via low-dose lithium could be a potential therapeutic strategy for dilated cardiomyopathy and heart failure.

Lithium - Pharmacological and Toxicological Aspects: The Current State of the Art

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Lithium is the smallest monovalent cation with many different biological effects. Although lithium is present in the pharmacotherapy of psychiatric illnesses for decades, its precise mechanism of action is still not clarified. Today lithium represents first-line therapy for bipolar disorders (because it possesses both antimanic and antidepressant properties) and the adjunctive treatment for major depression (due to its antisuicidal effects). Beside, lithium showed some protective effects in neurological diseases including acute neural injury, chronic degenerative conditions, Alzheimer's disease as well as in treating leucopenia, hepatitis and some renal diseases. Recent evidence suggested that lithium also possesses some anticancer properties due to its inhibition of Glycogen Synthase Kinase 3 beta (GSK3β) which is included in the regulation of a lot of important cellular processes such as: glycogen metabolism, inflammation, immunomodulation, apoptosis, tissue injury, regeneration etc.

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Although recent evidence suggested a potential utility of lithium in different conditions, its broader use in clinical practice still trails. The reason for this is a narrow therapeutic index of lithium, numerous toxic effects in various organ systems and some clinically relevant interactions with other drugs. Additionally, it is necessary to perform more preclinical as well as clinical studies in order to a precise therapeutic range of lithium, as well as its detailed mechanism of action. The aim of this review is to summarize the current knowledge concerning the pharmacological and toxicological effects of lithium.

Derivation of whole blood biomonitoring equivalents for lithium for the interpretation of biomonitoring data

INTRODUCTION

Lithium salts have numerous industrial uses and are also used in the treatment of bipolar disorders. The main source of lithium exposure to the general population is drinking water and foods. Lithium is nephrotoxic at higher doses. Thus, oral exposure guidelines for lithium have been derived, including ICH's permitted daily exposure (PDE = 0.008 mg lithium/kg-bw/day) adopted by Health Canada and the United States Environmental Protection Agency's (U.S. EPA) provisional peer reviewed toxicity value (PPRTV = 0.002 mg lithium/kg-bw/day), both based on human data.

OBJECTIVE

To derive whole blood biomonitoring equivalents (BEs) associated with PDE and PPRTV to interpret population-level biomonitoring data in health risk context.

METHOD

A simple kinetic relationship based on plasma clearance value (0.5 L/kg-bw/day) and the oral absorption fraction (100%) was used to derive blood BEs for PDE and PPRTV.

RESULTS

This analysis resulted in BE values in plasma and whole blood of 16 and 10 μg/L, respectively, based on the PDE values developed by the Health Canada and of 4.2 and 2.7 μg/L, respectively, based on the PPRTV developed by U.S. EPA.

CONCLUSION

The derived BE values can be used to interpret population-level biomonitoring data.

Alkali and Alkaline-Earth Cations in Complexes with Small Bioorganic Ligands: Ab Initio Benchmark Calculations and Bond Energy Decomposition

Herein, we report a computational database for the complexes of alkali [Li(I), Na(I), K(I)] and alkaline-earth [Be(II), Mg(II) and Ca(II)] cations with 25 small ligands with varying charge and donor atoms ("O", "N", and "S") that provides geometries and accurate bond energies useful to analyze metal-ligand interactions in proteins and nucleic acids. The role of the ligand→metal charge transfer, the equilibrium bond distance, the electronegativity of the donor atom, the ligand polarizability, and the relative stability of the complexes are discussed in detail. The interacting quantum atoms (IQA) method is used to decompose the binding energy into electrostatic and quantum mechanical contributions. In addition, bond energies are also estimated by means of multipolar electrostatic calculations. No simple correlation exists between bond energies and structural/electronic descriptors unless the data are segregated by the type of ligand or metal. The electrostatic attraction of some molecules (H₂ O, NH₃ , CH₃ OH) towards the metal cations is well reproduced using their (unrelaxed) atomic multipoles, but the same comparison is much less satisfactory for other ligands (e. g. benzene, thiol/thiolate groups, etc.). Besides providing reference structures and bond energies, the database can contribute to validate molecular mechanics potentials capable of yielding a balanced description of alkali and alkaline-earth metals binding to biomolecules.

Genetic Transformation of the Filamentous Fungus Pseudogymnoascus verrucosus of Antarctic Origin

Cold-adapted fungi isolated from Antarctica, in particular those belonging to the genus Pseudogymnoascus, are producers of secondary metabolites with interesting bioactive properties as well as enzymes with potential biotechnological applications. However, at genetic level, the study of these fungi has been hindered by the lack of suitable genetic tools such as transformation systems. In fungi, the availability of transformation systems is a key to address the functional analysis of genes related with the production of a particular metabolite or enzyme. To the best of our knowledge, the transformation of Pseudogymnoascus strains of Antarctic origin has not been achieved yet. In this work, we describe for the first time the successful transformation of a Pseudogymnoascus verrucosus strain of Antarctic origin, using two methodologies: the polyethylene glycol (PEG)-mediated transformation, and the electroporation of germinated conidia. We achieved transformation efficiencies of 15.87 ± 5.16 transformants per μg of DNA and 2.67 ± 1.15 transformants per μg of DNA for PEG-mediated transformation and electroporation of germinated conidia, respectively. These results indicate that PEG-mediated transformation is a very efficient method for the transformation of this Antarctic fungus. The genetic transformation of Pseudogymnoascus verrucosus described in this work represents the first example of transformation of a filamentous fungus of Antarctic origin.

How does the mood stabilizer lithium bind ATP, the energy currency of the cell: Insights from solid-state NMR

BACKGROUND

Lithium, in the form of a salt, is a mood stabilizer and a leading drug for the treatment of bipolar disorder. It has a very narrow therapeutic range and a variety of side effects. Lithium can replace magnesium and other cations in enzymes and small molecules, among them ATP, thereby affecting and inhibiting many biochemical pathways. The form of binding of lithium ions to ATP is not known.

METHODS

Here we extract the binding environment of lithium in solid ATP using a multi-nuclear multi-dimensional solid-state NMR approach.

RESULTS

We determine that the coordination sphere of lithium includes, at a distance of 3.0(±0.4) Å, three phosphates; the two phosphates closest to the ribose ring from one ATP molecule, and the middle phosphate from another ATP molecule. A water molecule most probably completes the fourth coordination. Despite the use of excess lithium in the preparations, sodium ions still remain bound to the sample, at distances of 4.3-5.5 Å from Li, and coordinate the first phosphate and two terminal phosphates.

CONCLUSIONS

Solid-state NMR enables to unravel the exact coordination of lithium in ATP showing binding to three phosphates from two molecules, none of which are the terminal gamma phosphate.

GENERAL SIGNIFICANCE

The methods we use are applicable to study lithium bound to a variety of ATP-bound enzymes, or to other cellular targets of lithium, consequently suggesting a molecular basis for its mode of action.

Free and Bound Therapeutic Lithium in Brain Signaling

Lithium, a first-line therapy for bipolar disorder, is effective in preventing suicide and new depressive/manic episodes. Yet, how this beguilingly simple monocation with only two electrons could yield such profound therapeutic effects remains unclear. An in-depth understanding of lithium's mechanisms of actions would help one to develop better treatments limiting its adverse side effects and repurpose lithium for treating traumatic brain injury and chronic neurodegenerative diseases. In this Account, we begin with a comparison of the physicochemical properties of Li⁺ and its key native rivals, Na⁺ and Mg²⁺, to provide physical grounds for their competition in protein binding sites. Next, we review the abnormal signaling pathways and proteins found in bipolar patients, who generally have abnormally high intracellular Na⁺ and Ca²⁺ concentrations, high G-protein levels, and hyperactive phosphatidylinositol signaling and glycogen synthase kinase-3β (GSK3β) activity. We briefly summarize experimental findings on how lithium, at therapeutic doses, modulates these abnormal signaling pathways and proteins. Following this survey, we address the following aspects of lithium's therapeutic actions: (1) Can Li⁺ displace Na⁺ from the allosteric Na⁺-binding sites in neurotransmitter transporters and G-protein coupled receptors (GPCRs); if so, how would this affect the host protein's function? (2) Why are certain Mg²⁺-dependent enzymes targeted by Li⁺? (3) How does Li⁺ binding to Mg²⁺-bound ATP/GTP (denoted as NTP) in solution affect the cofactor's conformation and subsequent recognition by the host protein? (4) How do NTP-Mg-Li complexes modulate the properties of the respective cellular receptors and signal-transducing proteins? We show that Li⁺ may displace Na⁺ from allosteric Na⁺-binding sites in certain GPCRs and stabilize inactive conformations, preventing these receptors from relaying signal to the respective G-proteins. It may also displace Mg²⁺ in enzymes containing highly cationic Mg²⁺-binding sites such as GSK3β, but not in enzymes containing Mg²⁺-binding sites with low or zero charge. We further show that Li⁺ binding to Mg²⁺-NTP in water does not alter the NTP conformation, which is locked by all three phosphates binding to Mg²⁺. However, bound lithium in the form of [NTP-Mg-Li]^2- dianions can activate or inhibit the host protein depending on the NTP-binding pocket's shape, which determines the metal-binding mode: The ATP-binding pocket's shape in the P2X receptor is complementary to the native ATP-Mg solution conformation and nicely fits [ATP-Mg-Li]^2-. However, since the ATP βγ phosphates bind Li⁺, bimetallic [ATP-Mg-Li]^2- may be more resistant to hydrolysis than the native cofactor, enabling ATP to reside longer in the binding site and elicit a prolonged P2X response. In contrast, the elongated GTP-binding pockets in G-proteins allow only two GTP phosphates to bind Mg²⁺, so the GTP conformation is no longer "triply-locked". Consequently, Li⁺ binding to GTP-Mg can significantly alter the native cofactor's structure, lowering the activated G-protein level, thus attenuating hyperactive G-protein-mediated signaling in bipolar patients. In summary, we have presented a larger "connected" picture of lithium's diverse effects based on its competition as a free monocation with native cations or as a phosphate-bound polyanionic complex modulating the host protein function.

Interactions of Monovalent and Divalent Cations at Palmitoyl-Oleoyl-Phosphatidylcholine Interface

Li⁺ is a biologically active and medically important cation. Experiments show that Li⁺ modulates some phospholipid bilayer properties in a manner similar to divalent cations, rather than other monovalent cations. We previously performed a comparative simulation study of the interaction of several monovalent cations with palmitoyl-oleoyl-phosphatidylcholine bilayers and reported that Li⁺ exhibited the highest association with lipids and formed a unique tetrahedral coordinated structure with lipid head groups. Here we extend these studies to two biologically important divalent cations, Mg²⁺ and Ca²⁺, and observe that, just like monovalent cations, Mg²⁺ and Ca²⁺ reduce bilayer areas and increase chain order. Bilayer area changes induced by cations are strongly correlated with the amount of charge inside the headgroup region; however, Mg²⁺ and Li⁺ are clear outliers. At the same time though, Mg²⁺ adsorption in the bilayer is the smallest among all cations, which is in contrast to Li⁺ that binds strongly to lipids. In fact, in contrast to all other cations, Mg²⁺ remains fully hydrated in the lipid headgroup region. However, Li⁺ and Mg²⁺ share high overlap between their inner-shell coordination topologies. This suggests that Li⁺ can structurally replace Mg²⁺, which is bound to other biomolecules with up to fourfold coordination, provided such replacement is energetically feasible. We compute structural topologies and compare them quantitatively using a new weighted-graphs-based method. Finally, we find that the specificity of cation interaction with lipid head groups exhibit consistent trend with the solvation shell energetics of ions in lipid headgroup and bulk water regions.

Lithium and Not Acetoacetate Influences the Growth of Cells Treated with Lithium Acetoacetate

The ketogenic diet (KD), a high-fat/low-carbohydrate/adequate-protein diet, has been proposed as a treatment for a variety of diseases, including cancer. KD leads to generation of ketone bodies (KBs), predominantly acetoacetate (AcAc) and 3-hydroxy-butyrate, as a result of fatty acid oxidation. Several studies investigated the antiproliferative effects of lithium acetoacetate (LiAcAc) and sodium 3-hydroxybutyrate on cancer cells in vitro. However, a critical point missed in some studies using LiAcAc is that Li ions have pleiotropic effects on cell growth and cell signaling. Thus, we tested whether Li ions per se contribute to the antiproliferative effects of LiAcAc in vitro. Cell proliferation was analyzed on neuroblastoma, renal cell carcinoma, and human embryonic kidney cell lines. Cells were treated for 5 days with 2.5, 5, and 10 mM LiAcAc and with equimolar concentrations of lithium chloride (LiCl) or sodium chloride (NaCl). LiAcAc affected the growth of all cell lines, either negatively or positively. However, the effects of LiAcAc were always similar to those of LiCl. In contrast, NaCl showed no effects, indicating that the Li ion impacts cell proliferation. As Li ions have significant effects on cell growth, it is important for future studies to include sources of Li ions as a control.

Lithium Preparations in Psychiatry, Addiction Medicine and Neurology. Part II. Biochemical Mechanisms of Its Action

Lithium is the first and the lightest in the series of alkali metals, to which, in addition to lithium, two very biologically important elements – sodium and potassium, as well as trace elements rubidium and cesium, belong. Despite its formal affiliation to the group of alkali metals, lithium, like many other chemical elements of the «atypical» second period of the periodic table (for example, boron), is more similar in its chemical properties not to its counterparts in the group, but to its «diagonal brother» – magnesium. As we will show in this article, the diagonal chemical similarity between lithium and magnesium is of great importance for understanding the mechanisms of its intracellular biochemical action. At the same time, the intragroup chemical similarity of lithium with sodium and potassium is more important for understanding the mechanisms of its absorption, its distribution in the body and its excretion. Despite the 70 years that have passed since John Cade’s discovery of the antimanic effect of lithium, the mechanisms of its therapeutic action are still not completely understood. In the end, it turns out that the mechanism of the therapeutic action of lithium is extremely complex, multicomponent, unique and not imitable. Certain aspects of the mechanism of its action may be compatible with the mechanisms of action of other mood stabilizers, or with the mechanisms of action of so-called «lithium-mimetics», such as ebselen. However, no other drug to date failed to fully reproduce the biochemical effect of lithium on the body.

Systems Biology Understanding of the Effects of Lithium on Cancer

Lithium has many widely varying biochemical and phenomenological effects, suggesting that a systems biology approach is required to understand its action. Multiple lines of evidence point to lithium as a significant factor in development of cancer, showing that understanding lithium action is of high importance. In this paper we undertake first steps toward a systems approach by analyzing mutual enrichment between the interactomes of lithium-sensitive enzymes and the pathways associated with cancer. This work integrates information from two important databases, STRING, and KEGG pathways. We find that for the majority of cancer pathways the mutual enrichment is statistically highly significant, reinforcing previous lines of evidence that lithium is an important influence on cancer.

Alkali ion influence on structure and stability of fibrillar amyloid-β oligomers

Alzheimer's disease is characterized by the aggregation of Amyloid-β (Aβ) peptide into oligomers, fibrils and plaques. Many factors influencing this process as well as the stability of the various Aβ aggregates are known to date, and include the concentration and type of metal ions. Most experimental and theoretical studies have concentrated on heavy metal ions, like Fe²⁺, Zn²⁺, or Cu²⁺, while the smaller alkali ions Li⁺, Na⁺, and K⁺ have not gained much attention notwithstanding their role and ubiquity in physiological environments. In this work, we applied atomistic molecular dynamics simulations to investigate the potential role of these alkali ions in stabilizing fibrillar Aβ oligomers of different size and topology, i.e., single and double filament systems comprising 3-24 peptide chains per filament. We find a pronounced difference on the molecular level in the interaction behavior with free carboxylate groups of the Aβ oligomer: Li⁺ forms stable bridged interactions, whereas K⁺ interacts more transiently and lacks bridging. The behavior of Na⁺ is in between, so that this ion-protein interaction obeys the renowned Hofmeister series. These differences are also reflected in the ability of the alkali ions to stabilize the oligomer secondary structure. The stabilizing effect is most pronounced for the smaller fibrillar oligomers, suggesting that the type of alkali ion critically affects the initial stages of fibril formation. Our findings thus offer a molecular explanation for the observation that the polymorphisms of Aβ fibril structures are caused by differences in the surrounding ionic environment. Graphical abstract Influence of alkali ions on the structure and stability of fibrillar amyloid-β oligomers.

Systems Biology Understanding of the Effects of Lithium on Affective and Neurodegenerative Disorders

Lithium has many widely varying biochemical and phenomenological effects, suggesting that a systems biology approach is required to understand its action. Multiple lines of evidence point to lithium intake and consequent blood levels as important determinants of incidence of neurodegenerative disease, showing that understanding lithium action is of high importance. In this paper we undertake first steps toward a systems approach by analyzing mutual enrichment between the interactomes of lithium-sensitive enzymes and the pathways associated with affective and neurodegenerative disorders. This work integrates information from two important databases, STRING and KEGG pathways. We find that for the majority of neurodegenerative disorders the mutual enrichment is many times greater than chance, reinforcing previous lines of evidence that lithium is an important influence on incidence of neurodegeneration. Our work suggests rational prioritization for which disorders are likely to be most sensitive to lithium and identifies genes that are likely to be useful targets for therapy adjunct to lithium.

Lithium chloride (LiCl) induced autophagy and downregulated expression of transforming growth factor β-induced protein (TGFBI) in granular corneal dystrophy

This study evaluated whether lithium chloride (LiCl) prevents cytoplasmic accumulation of mutant-transforming growth factor β-induced protein (Mut-TGFBI) in granular corneal dystrophy (GCD) via activation of the autophagy pathway. Levels of TGFBI and microtubule-associated protein 1A/1B-light chain 3 (LC3) in 3 GCD patients and healthy controls were analyzed by immunohistochemistry (IHC) staining and Western blot. Primary corneal fibroblasts were isolated and transfected with wild type or mutant type TGFBI over-expressed vectors, and then treated with LiCl and/or autophagy inhibitor 3-methyladenine (3-MA). Then, levels of TGFBI, glycogen synthase kinase-3 (GSK-3) and LC3-I/-II were detected. Cell viability and transmission electron microscopy assay were also performed. Levels of TGFBI and LC3 were significantly increased in GCD patients. Over-expression of mutant type TGFBI inhibited cell viability and induced autophagy in corneal fibroblasts. LiCl downregulated the expression of TGFBI in mutant type TGFBI over-expressed cells in a dose- and time-dependent manner. LiCl enhanced autophagy in mutant type TGFBI over-expressed cells and recovered cell viability in those cells. However, the effects of LiCl were partly attenuated when autophagy was suppressed by 3-MA. To summarize, treatment with LiCl inhibited the expression of TGFBI and recovery the inhibitory of mutant type TGFBI in cell viability, at least part through enhancing of autophagy. These data strongly suggest that LiCl may be useful in the treatment of GCD.