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International Journal of Bipolar... Jun 2024Decades of clinical research have demonstrated the efficacy of lithium in treating acute episodes (both manic and depressive), as well as in preventing recurrences of... (Review)
Review
BACKGROUND
Decades of clinical research have demonstrated the efficacy of lithium in treating acute episodes (both manic and depressive), as well as in preventing recurrences of bipolar disorder (BD). Specific to lithium is its antisuicidal effect, which appears to extend beyond its mood-stabilizing properties. Lithium's clinical effectiveness is, to some extent, counterbalanced by its safety and tolerability profile. Indeed, monitoring of lithium levels is required by its narrow therapeutic index. There is consensus that adequate serum levels should be above 0.6 mEq/L to achieve clinical effectiveness. However, few data support the choice of this threshold, and increasing evidence suggests that lithium might have clinical and molecular effects at much lower concentrations.
CONTENT
This narrative review is aimed at: (1) reviewing and critically interpreting the clinical evidence supporting the use of the 0.6 mEq/L threshold, (2) reporting a narrative synthesis of the evidence supporting the notion that lithium might be effective in much lower doses. Among these are epidemiological studies of lithium in water, evidence on the antisuicidal, anti-aggressive, and neuroprotective effects, including efficacy in preventing cognitive impairment progression, Alzheimer's disease (AD), and amyotrophic lateral sclerosis (ALS), of lithium; and (3) revieweing biological data supporting clinically viable uses of lithium at low levels with the delineation of a mechanistic hypothesis surrounding its purported mechanism of action. The study selection was based on the authors' preference, reflecting the varied and extensive expertise on the review subject, further enriched with an extensive pearl-growing strategy for relevant reviews and book sections.
CONCLUSIONS
Clinical and molecular effects of lithium are numerous, and its effects also appear to have a certain degree of specificity related to the dose administered. In sum, the clinical effects of lithium are maximal for mood stabilisation at concentrations higher than 0.6 mEq/l. However, lower levels may be sufficient for preventing depressive recurrences in older populations of patients, and microdoses could be effective in decreasing suicide risk, especially in patients with BD. Conversely, lithium's ability to counteract cognitive decline appears to be exerted at subtherapeutic doses, possibly corresponding to its molecular neuroprotective effects. Indeed, lithium may reduce inflammation and induce neuroprotection even at doses several folds lower than those commonly used in clinical settings. Nevertheless, findings surrounding its purported mechanism of action are missing, and more research is needed to investigate the molecular targets of low-dose lithium adequately.
PubMed: 38914810
DOI: 10.1186/s40345-024-00345-8 -
BioDrugs : Clinical Immunotherapeutics,... Jun 2024Antisense oligonucleotides (ASOs) are single stranded nucleic acids that target RNA. The US Food and Drug Administration has approved ASOs for several diseases. ASOs... (Review)
Review
Antisense oligonucleotides (ASOs) are single stranded nucleic acids that target RNA. The US Food and Drug Administration has approved ASOs for several diseases. ASOs utilize three principal modes of action (MOA). The first MOA is initiated by base-pairing between the ASO and its target mRNA, followed by RNase H-dependent mRNA degradation. The second MOA is triggered by ASOs that occlude splice acceptor sites in pre-mRNAs leading to skipping of a mutation-bearing exon. The third MOA involves ASOs that sterically hinder mRNA function, often inhibiting translation. ASOs contain a variety of modifications to the sugar-phosphate backbone and bases that stabilize the ASO or render them resistant to RNase activity. RNase H-dependent ASOs include inotersen and eplontersen (for hereditary transthyretin amyloidosis), fomiversen (for opportunistic cytomegalovirus infection), mipomersen (for familial hypercholesterolemia), and tofersen [for amyotrophic lateral sclerosis (ALS)]. Splice modulating ASOs include nursinersen (for spinal muscular atrophy) and eteplirsen, golodirsen, viltolarsen, and casimersen (all for the treatment of Duchenne muscular dystrophy). In addition, a designer ASO, milasen, was used to treat a single individual afflicted with Batten disease. Since ASO design relies principally upon knowledge of mRNA sequence, the bench to bedside pipeline for ASOs is expedient compared with protein-directed drugs. [Graphical abstract available.].
PubMed: 38914784
DOI: 10.1007/s40259-024-00665-2 -
Brain Research Jun 2024Neuroinflammation has been gaining attention as one of the potential causes of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and...
Neuroinflammation has been gaining attention as one of the potential causes of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis in recent years. The suppression of excessive proinflammatory responses is expected to be a target for the treatment and prevention of neurodegenerative diseases. Collapsin response mediator protein 4 (CRMP4) is involved in cytoskeleton-associated axonal guidance in the developing brain. Recently, the involvement of CRMP4 in several pathological conditions, including inflammation induced by lipopolysaccharide (LPS), a widely used inflammatory molecule, has been reported. However, the role of CRMP4 in LPS-induced inflammation in vivo remains largely unknown. In this study, we generated microglia-specific CRMP4 knockout mice for the first time and examined the role of CRMP4 in an LPS-induced brain inflammation model. We found that microglia after LPS injection in substantia nigra was significantly reduced in Crmp4 mice compared to Crmp4mice. The increased expression of IL-10 in striatum samples was downregulated in Crmp4 mice. A significant reduction in Iba1 expression was also observed in microglia-specific Crmp4 knockout mice compared with that in control mice. In contrast, the expression of IL-10 did not change in these mice, whereas arginase 1 (Arg1) expression was significantly suppressed. These results demonstrate the involvement of CRMP4 in LPS-induced inflammation in vivo, that CRMP4 suppresses microglial proliferation in a cell-autonomous manner.
PubMed: 38914219
DOI: 10.1016/j.brainres.2024.149094 -
Neurobiology of Disease Jun 2024Variability in disease onset and progression is a hallmark of amyotrophic lateral sclerosis (ALS), both in sporadic and genetic forms. Recently, we found that SOD1-G93A...
Variability in disease onset and progression is a hallmark of amyotrophic lateral sclerosis (ALS), both in sporadic and genetic forms. Recently, we found that SOD1-G93A transgenic mice expressing the same amount of mutant SOD1 but with different genetic backgrounds, C57BL/6JOlaHsd and 129S2/SvHsd, show slow and rapid muscle wasting and disease progression, respectively. Here, we investigated the different molecular mechanisms underlying muscle atrophy. Although both strains showed similar denervation-induced degradation of muscle proteins, only the rapidly progressing mice exhibited early and sustained STAT3 activation that preceded atrophy in gastrocnemius muscle. We therefore investigated the therapeutic potential of sunitinib, a tyrosine kinase inhibitor known to inhibit STAT3 and prevent cancer-induced muscle wasting. Although sunitinib treatment reduced STAT3 activation in the gastrocnemius muscle and lumbar spinal cord, it did not preserve spinal motor neurons, improve neuromuscular impairment, muscle atrophy and disease progression in the rapidly progressing SOD1-G93A mice. Thus, the effect of sunitinib is not equally positive in different diseases associated with muscle wasting. Moreover, given the complex role of STAT3 in the peripheral and central compartments of the neuromuscular system, the present study suggests that its broad inhibition may lead to opposing effects, ultimately preventing a potential positive therapeutic action in ALS.
PubMed: 38914173
DOI: 10.1016/j.nbd.2024.106576 -
JAMA Neurology Jun 2024
PubMed: 38913386
DOI: 10.1001/jamaneurol.2024.1922 -
Brain Communications 2024While voltage-gated potassium channels have critical roles in controlling neuronal excitability, they also have non-ion-conducting functions. Kv8.1, encoded by the KCNV1...
While voltage-gated potassium channels have critical roles in controlling neuronal excitability, they also have non-ion-conducting functions. Kv8.1, encoded by the KCNV1 gene, is a 'silent' ion channel subunit whose biological role is complex since Kv8.1 subunits do not form functional homotetramers but assemble with Kv2 to modify its ion channel properties. We profiled changes in ion channel expression in amyotrophic lateral sclerosis patient-derived motor neurons carrying a superoxide dismutase 1(A4V) mutation to identify what drives their hyperexcitability. A major change identified was a substantial reduction of KCNV1/Kv8.1 expression, which was also observed in patient-derived neurons with C9orf72 expansion. We then studied the effect of reducing KCNV1/Kv8.1 expression in healthy motor neurons and found it did not change neuronal firing but increased vulnerability to cell death. A transcriptomic analysis revealed dysregulated metabolism and lipid/protein transport pathways in KCNV1/Kv8.1-deficient motor neurons. The increased neuronal vulnerability produced by the loss of KCNV1/Kv8.1 was rescued by knocking down Kv2.2, suggesting a potential Kv2.2-dependent downstream mechanism in cell death. Our study reveals, therefore, unsuspected and distinct roles of Kv8.1 and Kv2.2 in amyotrophic lateral sclerosis-related neurodegeneration.
PubMed: 38911266
DOI: 10.1093/braincomms/fcae202 -
Clinical Drug Investigation Jun 2024The absence of a definitive cure for amyotrophic lateral sclerosis (ALS) emphasizes the crucial need to explore new and improved treatment approaches for this fatal,... (Review)
Review
The absence of a definitive cure for amyotrophic lateral sclerosis (ALS) emphasizes the crucial need to explore new and improved treatment approaches for this fatal, progressive, and disabling neurodegenerative disorder. As at the end of 2023, five treatments - riluzole, edaravone, dextromethorphan hydrobromide + quinidine sulfate (DHQ), tofersen, and sodium phenylbutyrate-tauroursodeoxycholic acid (PB-TUDCA) - were FDA approved for the treatment of patients with ALS. Among them PB-TUDCA has been shown to impact DNA processing impairments, mitochondria dysfunction, endoplasmic reticulum stress, oxidative stress, and pathologic folded protein agglomeration defects, which have been associated with ALS pathophysiology. The Phase 2 CENTAUR trial demonstrated significant impact of PB-TUDCA on the ALS Functional Rating Scale-Revised (ALSFRS-R) risk of death, hospitalization, and the need for tracheostomy or permanent assisted ventilation in patients with ALS based on post hoc analyses. More recently, contrasting with the CENTAUR trial results, results from the Phase 3 PHOENIX trial (NCT05021536) showed no change in ALSFRS-R total score at 48 weeks. Consequently, the sponsor company initiated the process with the US FDA and Health Canada to voluntarily withdraw the marketing authorizations for PB-TUDCA. In the present article, we review ALS pathophysiology, with a focus on PB-TUDCA's proposed mechanisms of action and recent clinical trial results and discuss the implications of conflicting trial data for ALS and other neurological disorders.
PubMed: 38909349
DOI: 10.1007/s40261-024-01371-1 -
Journal of Neurology Jun 2024The initiation of early non-invasive ventilation (NIV) often involves a careful balance between tolerance and effectiveness. In amyotrophic lateral sclerosis (ALS)...
BACKGROUND
The initiation of early non-invasive ventilation (NIV) often involves a careful balance between tolerance and effectiveness. In amyotrophic lateral sclerosis (ALS) patients, the establishment of a strategy, including the decision to focus on adhering to a cut-off, setting specific targets, or correcting all events, is crucial.
OBJECTIVE
To identify factors at 1 month after early at-home NIV initiation that are associated with improved survival in ALS patients. We explored the impacts of adherence (ADH), quality of treatment, and NIV parameters at 1 month after early at-home NIV initiation on patient survival.
METHODS
We conducted a retrospective study of 184 ALS patients at the Bordeaux ALS Centre for whom NIV was initiated between September 2017 and June 2021, and we collected data for a minimum period of 2 years after the last patient included. The primary outcome was the risk of death according to baseline characteristics of our population and the NIV parameters and monitoring during the early NIV initiation period. The secondary outcomes were association with NIV ADH during the early NIV initiation period on prognosis, and NIV ADH cut-off for good versus poor prognosis.
RESULTS
Among the 178 ALS patients analysed, we found that quality of NIV treatment and device settings did not significantly influence prognosis. However, low ADH was significantly associated with a higher risk of death. The use of NIV for > 5 h/day during the early NIV initiation period was linked to a decreased risk of death [hazard ratio = 0.4; 95% confidence interval: 0.27-0.9].
CONCLUSION
The use of NIV for > 5 h/day during the early NIV initiation period was associated with increased survival.
PubMed: 38909342
DOI: 10.1007/s00415-024-12523-w -
Scientific Data Jun 2024This research presents a dataset consisting of electroencephalogram and eye tracking recordings obtained from six patients with amyotrophic lateral sclerosis (ALS) in a...
This research presents a dataset consisting of electroencephalogram and eye tracking recordings obtained from six patients with amyotrophic lateral sclerosis (ALS) in a locked-in state and one hundred seventy healthy individuals. The ALS patients exhibited varying degrees of disease progression, ranging from partial mobility and weakened speech to complete paralysis and loss of speech. Despite these physical impairments, the ALS patients retained good eye function, which allowed them to use a virtual keyboard for communication. Data from ALS patients was recorded multiple times at their homes, while data from healthy individuals was recorded once in a laboratory setting. For each data recording, the experimental design involved nine recording sessions per participant, each corresponding to a common human action or demand. This dataset can serve as a valuable benchmark for several applications, such as improving spelling systems with brain-computer interfaces, investigating motor imagination, exploring motor cortex function, monitoring motor impairment progress in patients undergoing rehabilitation, and studying the effects of ALS on cognitive and motor processes.
Topics: Humans; Amyotrophic Lateral Sclerosis; Brain-Computer Interfaces; Electroencephalography; Eye-Tracking Technology
PubMed: 38909069
DOI: 10.1038/s41597-024-03501-y -
Biomedicine & Pharmacotherapy =... Jun 2024Cyclic adenosine monophosphate (cAMP) is a key second messenger that regulates signal transduction pathways pivotal for numerous biological functions. Intracellular cAMP... (Review)
Review
Cyclic adenosine monophosphate (cAMP) is a key second messenger that regulates signal transduction pathways pivotal for numerous biological functions. Intracellular cAMP levels are spatiotemporally regulated by their hydrolyzing enzymes called phosphodiesterases (PDEs). It has been shown that increased cAMP levels in the central nervous system (CNS) promote neuroplasticity, neurotransmission, neuronal survival, and myelination while suppressing neuroinflammation. Thus, elevating cAMP levels through PDE inhibition provides a therapeutic approach for multiple CNS disorders, including multiple sclerosis, stroke, spinal cord injury, amyotrophic lateral sclerosis, traumatic brain injury, and Alzheimer's disease. In particular, inhibition of the cAMP-specific PDE4 subfamily is widely studied because of its high expression in the CNS. So far, the clinical translation of full PDE4 inhibitors has been hampered because of dose-limiting side effects. Hence, focusing on signaling cascades downstream activated upon PDE4 inhibition presents a promising strategy, offering novel and pharmacologically safe targets for treating CNS disorders. Yet, the underlying downstream signaling pathways activated upon PDE(4) inhibition remain partially elusive. This review provides a comprehensive overview of the existing knowledge regarding downstream mediators of cAMP signaling induced by PDE4 inhibition or cAMP stimulators. Furthermore, we highlight existing gaps and future perspectives that may incentivize additional downstream research concerning PDE(4) inhibition, thereby providing novel therapeutic approaches for CNS disorders.
PubMed: 38908196
DOI: 10.1016/j.biopha.2024.117009