Folia Pharmacologica Japonica最新文献

Aging is a physiological process caused by various genetic and environmental factors. Recently, it has been proposed that the disturbance of the nutritional-metabolic sensing pathway is one of the aging characteristics. In particular, nicotinamide adenine dinucleotide (NAD⁺) plays an important role in this pathway and is considered the regulator of aging. NAD⁺ regulates an energy metabolism as a co-factor and is also involved in various biological processes including transcription, stress responses, DNA repair, inflammatory responses as well as post-transcriptional modifications, as a substrate for sirtuins, poly ADP-ribose polymerase (PARP), and CD38. With age, DNA damage and chronic inflammation increase in organs, resulting in overconsumption of NAD⁺ via PARP and CD38. The reduced NAD⁺ levels decrease the activity of sirtuins and PARPs and impair energy metabolism, ultimately leading to aging and aging-related diseases. However, the precise metabolism of NAD⁺ in vivo and the mechanism of how NAD⁺ regulates aging remain elusive. Moreover, the clinical application of NAD⁺ supplementation therapy is still under development. In this review, we overview the NAD⁺ metabolism and its relation to aging. In addition, we describe the current issue and perspective of NAD⁺ supplementation therapy to promote a healthy lifespan.

Hypoxic condition is formed in our body when the oxygen demand exceeds the supply. Hypoxic response is triggered under such condition to maintain homeostasis. However, it had been unclear for a long time how cells sense changes of surrounding oxygen environment and activate hypoxic response. Studies of molecular machinery responding to hypoxia largely progressed in the mid 90's after the identification of Hypoxia-Inducible Factor, HIF. Then, the prolyl hydroxylase domain-containing protein (PHD)-HIF pathway was characterized as a central pathway for cells to monitor the decrease in oxygen concentration and maintain cellular function in hypoxia. PHD is recognized as one of the cellular oxygen sensors because it requires oxygen molecule for its enzymatic activity. Importantly, there is a large enzyme family named 2-oxoglutarate-dependent dioxygenase (2OGDD), which require O₂, Fe²⁺, 2-oxoglutarate as co-factors like PHD. In this review, we will overview how 2OGDDs operate, and what are their roles in pathological situation. We also discuss possible direction of how we can establish drugs to target 2OGDDs.

In recent years, the "translational gap" has become problematic in drug development, wherein promising results from animal experiments and in vitro tests fail to demonstrate the expected efficacy and safety in clinical trials. This translational gap has also impacted on the development of therapeutic agents for brain diseases, including Alzheimer's disease (AD). While microglia, which are immune cells in the brain, have gained attention as therapeutic targets of AD, the inter-species difference in microglia between humans and experimental model animals may cause this gap. To reveal the pathogenic mechanisms of AD and develop a therapeutic strategy, experimental models that appropriately reproduce pathological conditions using human-derived materials are required. Pluripotent stem cells can differentiate into various cells such as neurons and microglia. Therefore, it is expected that the creation of neural organoids from human pluripotent stem cells will enable the construction of a human-based analysis system that can reproduce three-dimensional brain structures and intercellular interactions, thereby overcoming the translational gap. Furthermore, combining patient-derived induced pluripotent stem cells and gene editing technology with neural organoid technology is leading to cutting-edge research. In this review, we introduce global research trends aimed at developing neural organoids containing microglia derived from human pluripotent stem cells and applying them to elucidate the pathogenesis and to develop therapeutic drugs for AD.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the leading cause of dementia. Its pathological features include abnormal aggregation of amyloid-β (Aβ) and tau proteins, neuronal loss, and brain atrophy. The "amyloid hypothesis" suggests that Aβ accumulation triggers disease progression, leading to the development of anti-Aβ antibody therapies. However, their effectiveness is limited once dementia has developed, highlighting the need for early intervention in the preclinical stage. This review focuses on type 2 diabetes (T2D) and insulin resistance as acquired risk factors for AD, summarizing epidemiological and experimental evidence on their impact on AD neuropathology. While early postmortem studies produced inconsistent results regarding the association between T2D, insulin resistance, and Aβ deposition, recent amyloid PET imaging studies have clarified this relationship in the human brain. Additionally, animal studies suggest that diet-induced insulin resistance promotes Aβ accumulation. Conversely, genetic disruption of insulin signaling molecules significantly suppresses Aβ pathology. These seemingly contradictory findings suggest that while reduced brain insulin signaling may inhibit Aβ pathology, peripheral metabolic disturbances associated with worsening insulin resistance may accelerate Aβ deposition. Understanding the multifaceted roles of insulin signaling and the molecular basis of these complex interactions is crucial for identifying new preventive and disease-modifying therapeutic targets. Advancing this knowledge is essential for developing innovative AD treatments.

The global surge in antimicrobial resistance (AMR) highlights the critical need for the development of innovative therapies and the appropriate use of antimicrobial agents. Our research focused on preventing, managing, and mitigating the adverse effects of treatments for infection with methicillin-resistant Staphylococcus aureus. In this review, we present our investigations utilizing medical big data. The first study aimed to elucidate the relationship between renal outcome and survival following the onset of vancomycin-associated nephrotoxicity (VAN). An initial analysis using the US Food and Drug Administration Adverse Events Reporting System (FAERS) database revealed elevated mortality rates among patients with VAN compared with those without VAN, forming the basis for further investigation. A subsequent, more rigorous, retrospective analysis using electronic medical records confirmed that poor survival outcomes were significantly associated with non-recovery from VAN, particularly when progression to acute kidney injury of stage ≥2 occurred. Therefore, preventing progression to severe VAN is critical for enhancing survival outcomes. The second study investigated the relationship between statin use and daptomycin-related musculoskeletal adverse events. By employing a mixed-method approach combining meta-analysis with disproportionality analysis of the FAERS data, a significant association between statin therapy and daptomycin-related rhabdomyolysis was identified. This highlights the importance of cautious statin and daptomycin use, with careful consideration of potential safety risks. Each medical big-data database possesses unique characteristics that require careful consideration during analysis. The accurate interpretation of medical big data, coupled with its integration with complementary methodologies, will produce more robust and reliable research outcomes across diverse fields.

Glaucoma is an age-related neurodegenerative disease and the leading cause of blindness, but currently no fundamental treatment has been present. The main treatment is to reduce intraocular pressure, which is expected to delay the progression of the disease. However, there are many glaucoma patients for whom progression cannot be controlled by lowering intraocular pressure alone, and the development of a fundamental treatment is required. Meanwhile, the clinical application of gene therapy is increasing worldwide. Various gene therapy vectors are still being developed, and technological change is much faster in this field. Gene therapy has already been clinically applied to several neurodegenerative diseases, but gene therapy for glaucoma has not yet been established. Our group is investigating the development of a new treatment for glaucoma by gene therapy using neurotrophic factor signaling. And we aim not only to suppress disease progression by neuroprotection, but also to recover the visual function by axonal regeneration.