Bruk Getachew

Multiple Sclerosis (MS) is a chronic, immune-mediated disorder of the central nervous system characterized by leukocyte infiltration, inflammation, demyelination, and progressive neurodegeneration. Susceptibility to MS is influenced by genetic factors, including variants within the human leukocyte antigen (HLA) region, (notably HLA-DR15), and multiple single nucleotide polymorphisms that modulate T cell function and immune regulation. Clinically, early manifestations such as visual disturbances, sensory deficits, fatigue, and impaired coordination often precede more advanced features, including cognitive decline and bladder or bowel dysfunction. Although experimental and genetic models of neuroinflammation have facilitated the development of therapies that reduce relapse rates and slow disease progression, the underlying pathological mechanisms remain incompletely understood. Emerging evidence points to the importance of cytoskeletal organization and membrane-associated signaling platforms in maintaining neuronal and immune cell function. Disruption of these systems may contribute to demyelination and neuroinflammatory cascades. Within this context, a systems biology perspective is particularly valuable, as it emphasizes the integration of multiple, interdependent pathways rather than isolated mechanisms. Caveolin-1 (Cav-1), an integral membrane protein of caveolae, has gained attention as a potential central regulator due to its role in coordinating signaling processes across diverse cellular compartments. In this review, we examine the potential genetic and functional contributions of Cav-1 to MS pathophysiology, with a focus on its involvement in oxidative stress, inflammation, blood–brain barrier integrity, and autophagy. By framing these processes as components of an interconnected network, we highlight Cav-1 as a context-dependent modulator that may influence both disease progression and severity. However, despite its mechanistic relevance, the translational potential of Cav-1 remains uncertain, and further studies are required to clarify its precise role and evaluate its suitability as a therapeutic target in MS.

Multiple Sclerosis (MS), a chronic, immune-mediated disease of the central nervous system (CNS) is typified by leukocyte infiltration into CNS, inflammation, demyelination, and neurodegeneration. Risk factors include genetic predispositions involving HLA-DR15 and various single nucleotide polymorphisms affecting T cell function. Early signs such as blurred/double vision, numbness, fatigue, and balance coordination, are later accompanied by cognitive as well as bladder and bowel dysfunction. Genetic models of neuroinflammation have helped development of drugs with significant effects on progression and relapse rate of MS. Nonetheless, MS continues to pose major challenges as the pathological mechanisms remain unclear. Recent studies highlight the crucial role of quality and organization of cytoskeletal proteins in maintaining complex cellular functions such as neuronal excitability and neuroinflammation. Understanding how changes in these proteins impact demyelination is key to drug development for MS. Systems biology, an interdisciplinary field of study posits that complex interactions within biological systems contribute to the inflammatory processes and suggests that Cav-1, an integral membrane protein of caveolae with crucial role in cell signaling may provide a novel target in MS. Herein, we examine potential genetic influences on Cav-1 and its role in inflammation and demyelination in relation to MS. Specifically, its roles in oxidative stress, inflammation, blood brain barrier (BBB) integrity, and autophagy are discussed. Nonetheless, we conclude that translational aspect of Cav-1 and hence its specific therapeutic targeting in MS requires further exploration.

With the advent of medical technology and the sustenance of a longer lifespan, an increase in the number of age-related neurodegenerative diseases, including Parkinson’s disease (PD), is inevitable. Although current treatments for PD provide remarkable symptomatic relief for a few years, their side effects, combined with the progression in neurodegeneration, pose an urgent challenge for development of more effective treatments for this devastating disease. The challenge is further exacerbated by the unknown etiology in most PD cases. Nonetheless, progress in early identification of the premorbid/prodromal symptoms as well as understanding processes leading to their manifestation may help provide novel preventive and/or intervention strategies. The triad of the best-characterized and inter-related symptoms of prodromal PD include hyposmia (decrease sense of smell), constipation, and major depressive disorder (MDD). Recent revelations indicate a crucial role for the gut microbiota (GM) not only in maintaining the integrity of the gastrointestinal system but also that of the central nervous system via its bidirectional relationship with the brain, commonly referred to as the gut-brain-axis (GBA). Moreover, neuroinflammation, underscored by microglial activation, is believed to play a critical role in neurodegenerative as well as neuropsychiatric disorders including MDD. Here, we delve into the primary roles of GM/GBA and microglia, as well as their interactions, with the aim of providing novel diagnostic and/or treatments in PD. Regarding the treatments, we mention potential use of pre- post- or pro-biotics, and nicotinic or toll-like receptor modulators.

Trace amine-associated receptors (TAARs) are a class of G protein-coupled receptors that respond to metabolic derivatives of the amino acids such as phenylalanine, tyrosine, and tryptophan. Trace amines derive their name from the fact that their concentration in the periphery as well as in the central nervous system (CNS) is in trace amounts compared to the parent compound or other monoamine neurotransmitters such as dopamine, norepinephrine, or serotonin. Genetic, pharmacological and neurobiological studies have linked TAAR1, the most studied receptor of the TAARs to the pathophysiology of schizophrenia (SCZ), the current treatments of which are limited. Recent developments in the field implicate glial-microbiota interactions in SCZ pathophysiology. TAAR1 interactions with the glial cells and the gut microbiota (GM) makes it a suitable candidate as a novel target in SCZ. In this review, following brief descriptions of the known neurobiological substrates of SCZ, we delve into the specific roles of glial cells, including analysis of the public transcriptomic data, their interaction with GM and the potential integrator role of TAAR1 in glial-GM signaling relevant to SCZ. Finally, we suggest how TAAR1 manipulation may be exploited in this devastating neuropsychiatric disorder.

Huntington’s disease (HD) is a rare but progressive and devastating neurodegenerative disease characterized by involuntary movements, cognitive decline, executive dysfunction, and neuropsychiatric conditions such as anxiety and depression. It follows an autosomal dominant inheritance pattern. Thus, a child who has a parent with the mutated huntingtin (mHTT) gene has a 50% chance of developing the disease. Since the HTT protein is involved in many critical cellular processes, including neurogenesis, brain development, energy metabolism, transcriptional regulation, synaptic activity, vesicle trafficking, cell signaling, and autophagy, its aberrant aggregates lead to the disruption of numerous cellular pathways and neurodegeneration. Essential heavy metals are vital at low concentrations; however, at higher concentrations, they can exacerbate HD by disrupting glial–neuronal communication and/or causing dysbiosis (disturbance in the gut microbiota, GM), both of which can lead to neuroinflammation and further neurodegeneration. Here, we discuss in detail the interactions of iron, manganese, and copper with glial–neuron communication and GM and indicate how this knowledge may pave the way for the development of a new generation of disease-modifying therapies in HD.

Huntington’s disease (HD) is a rare but progressive and devastating neurodegenerative disease characterized by involuntary movements, cognitive decline, executive dysfunction, and neuropsychiatric conditions such as anxiety and depression. It follows an autosomal dominant inheritance pattern. Thus, a child who has a parent with the mutated huntingtin (mHTT) gene has a 50% chance of developing the disease. Since HTT protein is involved in many critical cellular processes including neurogenesis, brain development, energy metabolism, transcriptional regulation, synaptic activity, vesicle trafficking, cell signaling, and autophagy, its aberrant aggregates lead to disruption of numerous cellular pathways and neurodegeneration. Essential heavy metals are vital at low concentrations, however, at higher concentrations, can exacerbate HD by disrupting the glial-neuronal communication, and/or causing dysbiosis (disturbance in the gut microbiota, GM), both of which can lead to neuroinflammation and further neurodegeneration. Here, we discuss in detail the interactions of iron, manganese and copper with glial-neuron communication and GM and indicate how this knowledge may pave the way for development of a new generation of disease-modifying therapies in HD.

Mood disorders and substance use disorder (SUD) are of immense medical and social concern. Although significant progress on neuronal involvement in mood and reward circuitries has been achieved, it is only relatively recently that the role of glia in these disorders has attracted attention. Detailed understanding of the glial functions in these devastating diseases could offer novel interventions. Here, following a brief review of circuitries involved in mood regulation and reward perception, the specific contributions of neurotrophic factors, neuroinflammation, and gut microbiota to these diseases are highlighted. In this context, the role of specific glial cells (e.g., microglia, astroglia, oligodendrocytes, and synantocytes) on phenotypic manifestation of mood disorders or SUD are emphasized. In addition, use of this knowledge in the potential development of novel therapeutics is touched upon.

Major depressive disorder (MDD) and substance use disorder (SUD) are of immense medical and social concerns. Although significant progress on neuronal involvement in mood and reward circuitries has been achieved, only relatively recently the role of glia in these disorders have attracted attention. Detail understanding of the glial function in these devastating diseases could offer novel interventions. Here, following a brief review of circuitries involved in mood regulation and reward perception, specific contribution of the neurotrophic factors, neuroinflammation and gut microbiota to these diseases are highlighted. In this context, the role of specific glial cells (e.g., microglia, astroglia, oligodendrocytes and synantocytes) on phenotypic manifestation of MDD or SUD are emphasized. In addition, potential use of this knowledge in developing novel therapeutics is touched upon.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by severe deficits in social communication and interaction, repetitive movements, abnormal focusing on objects, or activity that can significantly affect the quality of life of the afflicted. Neuronal and glial cells have been implicated. It has a genetic component but can also be triggered by environmental factors or drugs. For example, prenatal exposure to valproic acid or acetaminophen, or ingestion of propionic acid, can increase the risk of ASD. Recently, epigenetic influences on ASD have come to the forefront of investigations on the etiology, prevention, and treatment of this disorder. Epigenetics refers to DNA modifications that alter gene expression without making any changes to the DNA sequence. Although an increasing number of pharmaceuticals and environmental chemicals are being implicated in the etiology of ASD, here, we specifically focus on the molecular influences of the abovementioned chemicals on epigenetic alterations in neuronal and glial cells and their potential connection to ASD. We conclude that a better understanding of these phenomena can lead to more effective interventions in ASD.

Parkinson’s disease (PD) is a progressive neurodegenerative disease characterized by resting tremor, bradykinesia, rigidity, and postural instability that also includes non-motor symptoms such as mood dysregulation. Dopamine (DA) is the primary neurotransmitter involved in this disease, but cholinergic imbalance has also been implicated. Current intervention in PD is focused on replenishing central DA, which provides remarkable temporary symptomatic relief but does not address neuronal loss and the progression of the disease. It has been well established that neuronal nicotinic cholinergic receptors (nAChRs) can regulate DA release and that nicotine itself may have neuroprotective effects. Recent studies identified nAChRs in nonneuronal cell types, including glial cells, where they may regulate inflammatory responses. Given the crucial role of neuroinflammation in dopaminergic degeneration and the involvement of microglia and astrocytes in this response, glial nAChRs may provide a novel therapeutic target in the prevention and/or treatment of PD. In this review, following a brief discussion of PD, we focus on the role of glial cells and, specifically, their nAChRs in PD pathology and/or treatment.