Repurposing drugs against Alzheimer's disease: can the anti-multiple sclerosis drug fingolimod (FTY720) effectively tackle inflammation processes in AD?

The potential capacities of FTY720: Novel therapeutic functions, targets, and mechanisms against diseases

Fingolimod (FTY720), an antagonist of sphingosine-1-phosphate (S1P), functions by binding to S1P receptors (S1PRs), excluding S1PR2. It received approval from the Food and Drug Administration (FDA) for the treatment of multiple sclerosis (MS) in 2010. As the first non-selective oral agonist for S1PRs, FTY720's diverse and systemic receptor expression often leads to alterations in various signaling pathways and multiple systems, making it a subject of intense research. Recent studies have identified a wide range of novel or potential functions for FTY720 beyond its application in MS. These include effects on the blood-brain barrier (BBB), vascular system, organelles, and cell death, as well as potential applications in organ transplantation, immune disorders, oncological conditions, neurological and psychiatric disorders, viral infections, and hypersensitivity diseases. This paper reviews the novel roles, targets, and mechanisms of FTY720 that hold promise for clinical utility. Additionally, it summarizes FTY720's derivation and development process, the characterization and mechanism of the structure of FTY720-P bound to S1PRs, the clinical safety profile, future challenges, and potential strategies to address them. These insights aim to guide future research and applications of FTY720, maximizing its therapeutic potential.

Repurposing drugs: promising therapeutic approach against Alzheimer's disease

Alzheimer's disease (AD) is an insidious, irreversible, complex neurodegenerative disorder characterized by progressive cognitive decline and memory loss; affecting millions worldwide. Despite decades of research, no effective disease-modifying treatment exists. However, drug repurposing is a progressive step in identifying new therapeutic uses of existing drugs. It has emerged as a promising strategy in the quest to combat AD. Various classes of repurposed drugs, such as antidiabetic, antihypertensive, antimicrobial, and anti-inflammatory, have shown potential neuroprotective effects in preclinical and clinical studies. These drugs act by combating free radicals generation, neuroinflammation, amyloid-beta aggregation, and tau hyper-phosphorylation. Furthermore, repurposing offers several advantages, including reduced time and cost compared to de novo drug development. It holds immense promise as a complementary approach to traditional drug discovery. Future research efforts should focus on elucidating the underlying mechanisms of repurposed drugs in AD, optimizing drug combinations, and conducting large-scale clinical trials to validate their efficacy and safety profiles. This review overviews recent advancements and findings in preclinical and clinical fields of different repurposed drugs for AD treatment.

Uncovering the Causal Link Between Obesity-Associated Genes and Multiple Sclerosis: A Systematic Literature Review

BACKGROUND

Multiple sclerosis (MS) is a multifaceted neurodegenerative disorder influenced by genetics and lifestyle. This systematic literature review investigates the role of six obesity-associated genes, including fat mass and obesity-associated (FTO), FAS apoptosis inhibitory molecule 2 (FAIM2), Niemann-Pick disease type C1-like 1 (NPC1), glucosamine-6-phosphate deaminase 2 (GNPDA2), melanocortin-4 receptor (MC4R), and brain-derived neurotrophic factor (BDNF) in the context of MS.

METHODS

A literature search was executed using Embase, Scopus, Cochrane, Web of Science, and PubMed databases from inception to July 2024. The related keywords employed during the search process are "fas apoptotic inhibitory molecule 2," "Niemann-Pick disease type C1," "fat mass and obesity-associated," "melanocortin-4 receptor," "brain-derived neurotrophic factor," "glucosamine-6-phosphate deaminase 2," and "multiple sclerosis."

RESULTS

Out of 2108 papers, 27 were entered into the present systematic literature review. The FTO gene may affect MS susceptibility through metabolic and inflammatory pathways. FAIM2 and NPC1 genes may contribute to MS pathogenesis, though their precise roles are still being elucidated. The GNPDA2 gene may have some connections with MS but requires further clarification. MC4R has demonstrated significant neuroprotective and anti-inflammatory effects, suggesting its potential impact on MS progression. BDNF plays a complex role in neuronal survival and repair and may influence the risk of MS.

CONCLUSION

Our findings demonstrated that obesity-related genes may have a significant impact on MS risk and disease course, revealing novel insights into the genetic underpinnings of MS.

Fingolimod ameliorates amyloid deposition and neurodegeneration in APP/PS1 mouse model of Alzheimer's disease

INTRODUCTION

The immune system plays a critical role in regulating amyloid-beta (Aβ) metabolism in Alzheimer's Disease (AD). Both T and B lymphocytes are involved in the pathogenesis of AD. The sphingosine-1-phosphate (S1P) receptor modulator fingolimod used in the treatment of multiple sclerosis, can promote lymphocyte homing, potentially reducing the infiltration of peripheral lymphocytes into the brain.

METHODS

In this study, 8-month-old APP/PS1 mice were orally administered fingolimod at a dose of 1 mg/kg/day or saline as a control for 2 months. After treatment, the mice were subjected to behavioral tests, pathological examinations, and biochemical analyses to evaluate behavioral deficits and AD-type pathologies.

RESULTS

Fingolimod inhibits the infiltration of peripheral lymphocytes into the brain and reduces neuroinflammation. Fingolimod enhances cognitive function and alleviates brain Aβ deposition. Additionally, fingolimod treatment mitigates other AD-related pathologies, including Tau hyperphosphorylation, neuroinflammation, and neurodegeneration. Proteomic analysis further confirms the therapeutic effects of fingolimod in AD, reflected by the downregulation of proteins involved in multiple AD-associated pathways.

DISCUSSION

This study illustrates that fingolimod effectively ameliorates multiple pathological features of AD, highlighting its potential as a promising therapeutic candidate for the disease.

Deep learning and generative artificial intelligence in aging research and healthy longevity medicine

With the global population aging at an unprecedented rate, there is a need to extend healthy productive life span. This review examines how Deep Learning (DL) and Generative Artificial Intelligence (GenAI) are used in biomarker discovery, deep aging clock development, geroprotector identification and generation of dual-purpose therapeutics targeting aging and disease. The paper explores the emergence of multimodal, multitasking research systems highlighting promising future directions for GenAI in human and animal aging research, as well as clinical application in healthy longevity medicine.

Fingolimod alleviates type 2 diabetes associated cognitive decline by regulating autophagy and neuronal apoptosis via AMPK/mTOR pathway

This study aimed to reveal the role of fingolimod (FTY720) in mice with type 2 diabetes-associated cognitive decline and explore its potential neuroprotective mechanism. Mice were divided into five groups: normal control, normal control + FTY720 (1.0 mg/kg/day), type 2 diabetes mellitus, type 2 diabetes mellitus + low-dose FTY720 (0.5 mg/kg/day), and type 2 diabetes mellitus + high-dose FTY720 (1.0 mg/kg/day). Different doses of FTY720 were administered daily for 8 weeks after the induction of type 2 diabetes using a four-week high-fat diet feeding combined with continuous low-dose intraperitoneal injections of streptozotocin. After 8 weeks of treatment, the body weights and fasting blood glucose levels of mice from the five groups were compared. Morris water maze and new object recognition tests were used to evaluate cognitive function. Pathological changes in the hippocampal CA1 region were observed using haematoxylin-eosin and Nissl staining, and the ultrastructure of the hippocampal neurones was assessed using transmission electron microscopy. The expression levels of autophagy- and apoptosis-related proteins, such as LC3, Beclin-1, P62, Bax, and Bcl-2, in the mice hippocampus were detected by western blotting. Simultaneously, AMPK/mTOR signaling pathway proteins were detected to understand the potential mechanism. FTY720 had no significant effect on the body weight or fasting blood glucose levels in mice with type 2 diabetes. However, both FTY720 doses improved the cognitive function and hippocampal damage. In addition, the results suggested that FTY720 dramatically decreased P62 and Bax levels and increased LC3 II/LC3 I ratio, Beclin-1, and Bcl-2 expression in the hippocampus of type 2 diabetic mice. FTY720 also affected the expression of the AMPK/mTOR signaling pathway. Thus, FTY720 improved cognitive function and hippocampal pathological changes in type 2 diabetic mice without affecting fasting blood glucose levels. Our results show that FTY720 may exert neuroprotective effects in vivo by enhancing hippocampal autophagy and inhibiting apoptosis via the AMPK/mTOR signaling pathway.

In-vivo neuronal dysfunction by Aβ and tau overlaps with brain-wide inflammatory mechanisms in Alzheimer's disease

The molecular mechanisms underlying neuronal dysfunction in Alzheimer's disease (AD) remain uncharacterized. Here, we identify genes, molecular pathways and cellular components associated with whole-brain dysregulation caused by amyloid-beta (Aβ) and tau deposits in the living human brain. We obtained in-vivo resting-state functional MRI (rs-fMRI), Aβ- and tau-PET for 47 cognitively unimpaired and 16 AD participants from the Translational Biomarkers in Aging and Dementia cohort. Adverse neuronal activity impacts by Aβ and tau were quantified with personalized dynamical models by fitting pathology-mediated computational signals to the participant's real rs-fMRIs. Then, we detected robust brain-wide associations between the spatial profiles of Aβ-tau impacts and gene expression in the neurotypical transcriptome (Allen Human Brain Atlas). Within the obtained distinctive signature of in-vivo neuronal dysfunction, several genes have prominent roles in microglial activation and in interactions with Aβ and tau. Moreover, cellular vulnerability estimations revealed strong association of microglial expression patterns with Aβ and tau's synergistic impact on neuronal activity (q < 0.001). These results further support the central role of the immune system and neuroinflammatory pathways in AD pathogenesis. Neuronal dysregulation by AD pathologies also associated with neurotypical synaptic and developmental processes. In addition, we identified drug candidates from the vast LINCS library to halt or reduce the observed Aβ-tau effects on neuronal activity. Top-ranked pharmacological interventions target inflammatory, cancer and cardiovascular pathways, including specific medications undergoing clinical evaluation in AD. Our findings, based on the examination of molecular-pathological-functional interactions in humans, may accelerate the process of bringing effective therapies into clinical practice.

Novel Compounds as S1P5 Modulators for Treating Neurodegenerative Diseases

Provided herein are novel compounds as S1P5 modulators, pharmaceutical compositions, use of such compounds in treating neurodegenerative diseases, particularly Alzheimer's disease, multiple sclerosis, migraine and amyotrophic lateral sclerosis, and processes for preparing such compounds.

Sphingosine 1-phosphate signaling axis mediates neuropeptide S-induced invasive phenotype of endometriotic cells

Endometriosis is a chronic gynecological syndrome characterized by endometrial cell invasion of the extra-uterine milieu, pelvic pain and infertility. Treatment relies on either symptomatic drugs or hormonal therapies, even though the mechanism involved in the onset of endometriosis is yet to be elucidated. The signaling of sphingolipid sphingosine 1-phosphate (S1P) is profoundly dysregulated in endometriosis. Indeed, sphingosine kinase (SK)1, one of the two isoenzymes responsible for S1P biosynthesis, and S1P1, S1P3 and S1P5, three of its five specific receptors, are more highly expressed in endometriotic lesions compared to healthy endometrium. Recently, missense coding variants of the gene encoding the receptor 1 for neuropeptide S (NPS) have been robustly associated with endometriosis in humans. This study aimed to characterize the biological effect of NPS in endometriotic epithelial cells and the possible involvement of the S1P signaling axis in its action. NPS was found to potently induce cell invasion and actin cytoskeletal remodeling. Of note, the NPS-induced invasive phenotype was dependent on SK1 and SK2 as well as on S1P1 and S1P3, given that the biological action of the neuropeptide was fully prevented when one of the two biosynthetic enzymes or one of the two selective receptors was inhibited or silenced. Furthermore, the RhoA/Rho kinase pathway, downstream to S1P receptor signaling, was found to be critically implicated in invasion and cytoskeletal remodeling elicited by NPS. These findings provide new information to the understanding of the molecular mechanisms implicated in endometriosis pathogenesis, establishing the rationale for non-hormonal therapeutic targets for its treatment.

Learning CNS immunopathology from therapeutic interventions

Modulation of immune cell trafficking across the blood-brain barrier has not only introduced a therapeutic avenue for multiple sclerosis (MS) but also represents an example of reverse translational medicine. Data from clinical trials of drugs such as natalizumab and fingolimod have revealed the involvement of different compartments in relapsing versus non-relapsing MS immune biology, contributed to our understanding of central nervous system (CNS) immune surveillance, and stimulated new fields of research. Here, we discuss the results of these trials, as well as patient biomaterial-based scientific projects, and how both have informed our understanding of CNS immunopathology.

Carboxylic Acid-Containing Indanyl Compounds as S1P5 Modulators for Treating Neurodegenerative Diseases

Provided herein are novel carboxylic acid-containing indanyl compounds as S1P5 modulators, pharmaceutical compositions, use of such compounds in treating neurodegenerative diseases, particularly Alzheimer's disease and multiple sclerosis, and processes for preparing such compounds.