Lithium and Atypical Antipsychotics: The Possible WNT/β Pathway Target in Glaucoma

Changes in the Protein Composition of the Aqueous Humor in Patients with Glaucoma: An Update Review

The study of the aqueous humor (AH) plays a key role in understanding the pathophysiology of glaucoma. The AH provides nutrition, maintains the appropriate intraocular pressure, and provides important information about the mechanisms of the disease. The development of modern technologies has allowed the use of more accurate analytical methods, which has proven to be a key factor in determining the changes occurring in the proteome of the aqueous humor of glaucoma patients. Recently, researchers have observed changes in the levels of proteins associated with inflammation, oxidative stress, the complement system, and extracellular matrix remodeling. They have also shown that these changes may be variable for different types of glaucoma. The objective of this review is to collect and summarize the current knowledge on the potential biomarkers and pathomechanisms involved in the pathogenesis of glaucoma. We hope that our review will contribute to the improvement of current diagnostic methods in this illness and, through a better understanding of the changes occurring during the progression of the disease, will enable the development of more effective preventive and therapeutic strategies in the future.

Long non-coding RNA SNHG11 regulates the Wnt/β-catenin signaling pathway through rho/ROCK in trabecular meshwork cells

Trabecular meshwork (TM) cell dysfunction is the leading cause of elevated intraocular pressure (IOP) and glaucoma. The long non-coding RNA (lncRNA) small nucleolar RNA host gene 11 (SNHG11) is associated with cell proliferation and apoptosis, but its biological functions and role in glaucoma pathogenesis remain unclear. In the present study, we investigated the role of SNHG11 in TM cells using immortalized human TM and glaucomatous human TM (GTM3 ) cells and an acute ocular hypertension mouse model. SNHG11 expression was depleted using siRNA targeting SNHG11. Transwell assays, quantitative real-time PCR analysis (qRT-PCR), western blotting, and CCK-8 assay were used to evaluate cell migration, apoptosis, autophagy, and proliferation. Wnt/β-catenin pathway activity was inferred from qRT-PCR, western blotting, immunofluorescence, and luciferase reporter and TOPFlash reporter assays. The expression of Rho kinases (ROCKs) was detected using qRT-PCR and western blotting. SNHG11 was downregulated in GTM3 cells and mice with acute ocular hypertension. In TM cells, SNHG11 knockdown inhibited cell proliferation and migration, activated autophagy, and apoptosis, repressing the Wnt/β-catenin signaling pathway, and activated Rho/ROCK. Wnt/β-catenin signaling pathway activity increased in TM cells treated with ROCK inhibitor. SNHG11 regulated Wnt/β-catenin signaling through Rho/ROCK by increasing GSK-3β expression and β-catenin phosphorylation at Ser33/37/Thr41 while decreasing β-catenin phosphorylation at Ser675. We demonstrate that the lncRNA SNHG11 regulates Wnt/β-catenin signaling through Rho/ROCK via β-catenin phosphorylation at Ser675 or GSK-3β-mediated phosphorylation at Ser33/37/Thr41, affecting cell proliferation, migration, apoptosis, and autophagy. Through its effects on Wnt/β-catenin signaling, SNHG11 is implicated in glaucoma pathogenesis and is a potential therapeutic target.

The Actions of Lithium on Glaucoma and Other Senile Neurodegenerative Diseases Through GSK-3 Inhibition: A Narrative Review

Glaucoma can be described as a set of progressive optic neuropathies. They cause a gradual, irreversible loss of the field of view, which concludes in complete blindness. Evidence suggests that patients who have glaucoma face a greater risk of suffering from senile dementia. Dementia is a group of conditions that occur in old age individuals. Neurodegeneration is a characteristic pathological feature of dementia, the progression of which causes a decline in cognition, which may be accompanied by memory loss. Severe dementia in old individuals usually presents as Alzheimer’s disease, which significantly contributes to a load of dementia in India. Parkinsonism is another common neurodegenerative disease that is known to occur in the elderly.

The WNT (Wingless-related integration site)/β-catenin pathway is a multistep process that is responsible for the regulation of various cellular functions. Lithium can up-regulate this pathway by disrupting Glycogen synthase kinase-3β (GSK-3β). This action of Lithium can effectively counteract neuroinflammation and neurodegeneration. The current use of Lithium remains majorly confined to its use for episodes of mania in bipolar disorder (BD). However, recent literature gives insight into how Lithium can improve the visual field in glaucomatous eyes. Symptomatic improvement after lithium administration is seen as it has neuroprotective actions on the retinal ganglion cells (RGCs). Prolonged lithium use improves axonal regeneration and neuronal survival. Lithium also improves the worsening of symptoms in other dementia-related neurodegenerative diseases like Alzheimer’s and Parkinsonism. The physiological actions of Lithium can be utilized in providing effective, holistic therapy options in pathologically related senile degenerative disorders. Significantly better results can be obtained if Lithium therapy is given in conjunction with the drugs used to manage these disorders.

Neuroinflammation in Schizophrenia: The Key Role of the WNT/β-Catenin Pathway

Schizophrenia is a very complex syndrome involving widespread brain multi-dysconnectivity. Schizophrenia is marked by cognitive, behavioral, and emotional dysregulations. Recent studies suggest that inflammation in the central nervous system (CNS) and immune dysfunction could have a role in the pathogenesis of schizophrenia. This hypothesis is supported by immunogenetic evidence, and a higher incidence rate of autoimmune diseases in patients with schizophrenia. The dysregulation of the WNT/β-catenin pathway is associated with the involvement of neuroinflammation in schizophrenia. Several studies have shown that there is a vicious and positive interplay operating between neuroinflammation and oxidative stress. This interplay is modulated by WNT/β-catenin, which interacts with the NF-kB pathway; inflammatory factors (including IL-6, IL-8, TNF-α); factors of oxidative stress such as glutamate; and dopamine. Neuroinflammation is associated with increased levels of PPARγ. In schizophrenia, the expression of PPAR-γ is increased, whereas the WNT/β-catenin pathway and PPARα are downregulated. This suggests that a metabolic-inflammatory imbalance occurs in this disorder. Thus, this research’s triptych could be a novel therapeutic approach to counteract both neuroinflammation and oxidative stress in schizophrenia.

Psychopharmacological Treatment, Intraocular Pressure and the Risk of Glaucoma: A Review of Literature

Through the years, the available psychopharmacological treatments have expanded with numerous new drugs. Besides weight gain, gastro-intestinal problems or Parkinson-like symptoms, ocular adverse effects of psychiatric drugs have been reported. These adverse effects are not common, but can be dangerous for the patient. This review summarises the current knowledge on the risk of raised intraocular pressure and glaucoma entailed by psychopharmacological treatment. Also, it provides updated data for clinicians involved in the treatment of patients with glaucoma or glaucoma risk factors. For this purpose, we performed an extensive literature search in the PubMed database using specific terms. Selective serotonin and noradrenaline reuptake inhibitors are the best evidenced as having no association with glaucoma. Antipsychotics, and especially first generation, seem to have no correlation with an increased intraocular pressure and therefore possibly with a risk of glaucoma, although a special attention should be paid when using ziprasidone. Tricyclic antidepressants, benzodiazepines and topiramate should be avoided in patients diagnosed with glaucoma or at risk. Clinicians should be aware of the possible psychotropic drug induced glaucoma and monitor at risk patients closely in order to prevent this condition. Irrespective of the psychopharmacological regimen taken into consideration, the glaucoma patient should be under the strict supervision of the ophthalmologist.