CART mitigates oxidative stress and DNA damage in memory deficits of APP/PS1 mice via upregulating β‑amyloid metabolism‑associated enzymes

Anorexigenic neuropeptides as anti-obesity and neuroprotective agents: exploring the neuroprotective effects of anorexigenic neuropeptides

Since 1975, the incidence of obesity has increased to epidemic proportions, and the number of patients with obesity has quadrupled. Obesity is a major risk factor for developing other serious diseases, such as type 2 diabetes mellitus, hypertension, and cardiovascular diseases. Recent epidemiologic studies have defined obesity as a risk factor for the development of neurodegenerative diseases, such as Alzheimer's disease (AD) and other types of dementia. Despite all these serious comorbidities associated with obesity, there is still a lack of effective antiobesity treatment. Promising candidates for the treatment of obesity are anorexigenic neuropeptides, which are peptides produced by neurons in brain areas implicated in food intake regulation, such as the hypothalamus or the brainstem. These peptides efficiently reduce food intake and body weight. Moreover, because of the proven interconnection between obesity and the risk of developing AD, the potential neuroprotective effects of these two agents in animal models of neurodegeneration have been examined. The objective of this review was to explore anorexigenic neuropeptides produced and acting within the brain, emphasizing their potential not only for the treatment of obesity but also for the treatment of neurodegenerative disorders.

The role of hydrogen therapy in Alzheimer's disease management: Insights into mechanisms, administration routes, and future challenges

Alzheimer's disease (AD) is a progressive neurodegenerative disorder predominantly affecting the elderly. While conventional pharmacological therapies remain the primary treatment for AD, their efficacy is limited effectiveness and often associated with significant side effects. This underscores the urgent need to explore alternative, non-pharmacological interventions. Oxidative stress has been identified as a central player in AD pathology, influencing various aspects including amyloid-beta metabolism, tau phosphorylation, autophagy, neuroinflammation, mitochondrial dysfunction, and synaptic dysfunction. Among the emerging non-drug approaches, hydrogen therapy has garnered attention for its potential in mitigating these pathological conditions. This review provides a comprehensively overview of the therapeutic potential of hydrogen in AD. We delve into its mechanisms of action, administration routes, and discuss the current challenges and future prospects, with the aim of providing valuable insights to facilitate the clinical application of hydrogen-based therapies in AD management.

Oxygen metabolism abnormality and Alzheimer's disease: An update

Oxygen metabolism abnormality plays a crucial role in the pathogenesis of Alzheimer's disease (AD) via several mechanisms, including hypoxia, oxidative stress, and mitochondrial dysfunction. Hypoxia condition usually results from living in a high-altitude habitat, cardiovascular and cerebrovascular diseases, and chronic obstructive sleep apnea. Chronic hypoxia has been identified as a significant risk factor for AD, showing an aggravation of various pathological components of AD, such as amyloid β-protein (Aβ) metabolism, tau phosphorylation, mitochondrial dysfunction, and neuroinflammation. It is known that hypoxia and excessive hyperoxia can both result in oxidative stress and mitochondrial dysfunction. Oxidative stress and mitochondrial dysfunction can increase Aβ and tau phosphorylation, and Aβ and tau proteins can lead to redox imbalance, thus forming a vicious cycle and exacerbating AD pathology. Hyperbaric oxygen therapy (HBOT) is a non-invasive intervention known for its capacity to significantly enhance cerebral oxygenation levels, which can significantly attenuate Aβ aggregation, tau phosphorylation, and neuroinflammation. However, further investigation is imperative to determine the optimal oxygen pressure, duration of exposure, and frequency of HBOT sessions. In this review, we explore the prospects of oxygen metabolism in AD, with the aim of enhancing our understanding of the underlying molecular mechanisms in AD. Current research aimed at attenuating abnormalities in oxygen metabolism holds promise for providing novel therapeutic approaches for AD.

To re-examine the intersection of microglial activation and neuroinflammation in neurodegenerative diseases from the perspective of pyroptosis

Neurodegenerative diseases (NDs), such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and motor neuron disease, are diseases characterized by neuronal damage and dysfunction. NDs are considered to be a multifactorial disease with diverse etiologies (immune, inflammatory, aging, genetic, etc.) and complex pathophysiological processes. Previous studies have found that neuroinflammation and typical microglial activation are important mechanisms of NDs, leading to neurological dysfunction and disease progression. Pyroptosis is a new mode involved in this process. As a form of programmed cell death, pyroptosis is characterized by the expansion of cells until the cell membrane bursts, resulting in the release of cell contents that activates a strong inflammatory response that promotes NDs by accelerating neuronal dysfunction and abnormal microglial activation. In this case, abnormally activated microglia release various pro-inflammatory factors, leading to the occurrence of neuroinflammation and exacerbating both microglial and neuronal pyroptosis, thus forming a vicious cycle. The recognition of the association between pyroptosis and microglia activation, as well as neuroinflammation, is of significant importance in understanding the pathogenesis of NDs and providing new targets and strategies for their prevention and treatment.

Expression and role of cocaine-amphetamine regulated transcript (CART) in the proliferation of biliary epithelium

Cholangiocytes, the epithelial cells that line the biliary tree, can proliferate under the stimulation of several factors through both autocrine and paracrine pathways. The cocaine-amphetamine-regulated-transcript (CART) peptide has several physiological functions, and it is widely expressed in several organs. CART increases the survival of hippocampal neurons by upregulating brain-derived neurotrophic factor (BDNF), whose expression has been correlated to the proliferation rate of cholangiocytes. In the present study, we aimed to evaluate the expression of CART and its role in modulating cholangiocyte proliferation in healthy and bile duct ligated (BDL) rats in vivo, as well as in cultured normal rat cholangiocytes (NRC) in vitro. Liver samples from both healthy and BDL (1 week) rats, were analyzed by immunohistochemistry and immunofluorescence for CART, CK19, TrkB and p75NTR BDNF receptors. PCNA staining was used to evaluate the proliferation of the cholangiocytes, whereas TUNEL assay was used to evaluate biliary apoptosis. NRC treated or not with CART were used to confirm the role of CART on cholangiocytes proliferation and the secretion of BDNF. Cholangiocytes proliferation, apoptosis, CART and TrkB expression were increased in BDL rats, compared to control rats. We found a higher expression of TrkB and p75NTR, which could be correlated with the proliferation rate of biliary tree during BDL. The in vitro study demonstrated increased BDNF secretion by NRC after treatment with CART compared with control cells. As previously reported, proliferating cholangiocytes acquire a neuroendocrine phenotype, modulated by several factors, including neurotrophins. Accordingly, CART may play a key role in the remodeling of biliary epithelium during cholestasis by modulating the secretion of BDNF.

Alzheimer's Disease and Impaired Bone Microarchitecture, Regeneration and Potential Genetic Links

Alzheimer's Disease (AD) and osteoporosis are both age-related degenerative diseases. Many studies indicate that these two diseases share common pathogenesis mechanisms. In this review, the osteoporotic phenotype of AD mouse models was discussed, and shared mechanisms such as hormonal imbalance, genetic factors, similar signaling pathways and impaired neurotransmitters were identified. Moreover, the review provides recent data associated with these two diseases. Furthermore, potential therapeutic approaches targeting both diseases were discussed. Thus, we proposed that preventing bone loss should be one of the most important treatment goals in patients with AD; treatment targeting brain disorders is also beneficial for osteoporosis.

HIF-1 signalling pathway was identified as a potential new pathway for Icariin's treatment against Alzheimer's disease based on preclinical evidence and bioinformatics

Aim: Alzheimer's disease (AD) is a neurodegenerative condition that is characterized by the gradual loss of memory and cognitive function. Icariin, which is a natural chemical isolated from Epimedii herba, has been shown to protect against AD. This research examined the potential mechanisms of Icariin's treatment against AD via a comprehensive review of relevant preclinical studies coupled with network pharmacology. Methods: The PubMed, Web of Science, CNKI, WANFANG, and VIP databases were used to identify the relevant studies. The pharmacological characteristics of Icariin were determined using the SwissADME and TCMSP databases. The overlapping targets of Icariin and AD were then utilized to conduct disease oncology (DO) analysis to identify possible hub targets of Icariin in the treatment of AD. The hub targets were then used for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses, and the interactions of the targets and Icariin were assessed via molecular docking and molecular dynamics simulation (MDS). Results: According to the literature review, Icariin alleviates cognitive impairment by regulating the expression of Aβ1-42, Aβ1-40, BACE1, tau, hyperphosphorylated tau, and inflammatory mediators. DO analysis revealed 35 AD-related hub targets, and the HIF-1 signalling pathway was ranked first according to the KEGG pathway analysis. Icariin effectively docked with the 35 hub targets and HIF-1α, and the dynamic binding of the HIF-1-Icariin complex within 100 ns indicated that Icariin contributed to the stability of HIF-1α. Conclusion: In conclusion, our research used a literature review and network pharmacology methods to identify the HIF-1 signalling pathway as a potential pathway for Icariin's treatment against AD.

Therapeutic non-invasive brain treatments in Alzheimer's disease: recent advances and challenges

Alzheimer's disease (AD) is one of the major neurodegenerative diseases and the most common form of dementia. Characterized by the loss of learning, memory, problem-solving, language, and other thinking abilities, AD exerts a detrimental effect on both patients' and families' quality of life. Although there have been significant advances in understanding the mechanism underlying the pathogenesis and progression of AD, there is no cure for AD. The failure of numerous molecular targeted pharmacologic clinical trials leads to an emerging research shift toward non-invasive therapies, especially multiple targeted non-invasive treatments. In this paper, we reviewed the advances of the most widely studied non-invasive therapies, including photobiomodulation (PBM), transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), and exercise therapy. Firstly, we reviewed the pathological changes of AD and the challenges for AD studies. We then introduced these non-invasive therapies and discussed the factors that may affect the effects of these therapies. Additionally, we review the effects of these therapies and the possible mechanisms underlying these effects. Finally, we summarized the challenges of the non-invasive treatments in future AD studies and clinical applications. We concluded that it would be critical to understand the exact underlying mechanisms and find the optimal treatment parameters to improve the translational value of these non-invasive therapies. Moreover, the combined use of non-invasive treatments is also a promising research direction for future studies and sheds light on the future treatment or prevention of AD.

MicroRNA-668-3p regulates oxidative stress and cell damage induced by Aβ1-42 by targeting the OXR1/p53-p21 axis

Background

Alzheimer’s disease (AD) is the most common type of dementia in old age and has become a serious social and medical problem threatening human health. We aimed to explore the mechanisms underlying AD development by screening for microRNAs (miRNAs) that affect AD progression and examining their role in AD development.

Methods

Hematoxylin-eosin (HE) staining, immunohistochemistry, and immunofluorescence (IF) were used to analyze the characteristics of the hippocampus, neuron cell separation, and related protein expression in mice. We used Gene Expression Omnibus (GEO) data analysis to screen miRNAs and mRNAs that affect AD progression, and quantitative reverse transcription polymerase chain reaction (RT-qPCR) and western blot analysis to determine changes in miRNA and mRNA levels before and after amyloid β (Aβ)1-42 induction. In addition, we used luciferase analysis to examine miRNA and mRNA binding and the effect of miRNA/mRNA interaction on neuronal cell proliferation. Apoptosis and reactive oxygen species (ROS) levels were examined using Cell Counting Kit-8 analysis and flow cytometry (FCM), respectively. The enzyme-linked immunosorbent assay was used to analyze changes in neuronal cell-secreted oxidative stress-related protein levels through miRNA/mRNA interaction.

Results

Oxidative stress levels were significantly increased in the AD mouse model. GEO data analysis revealed 67 dysregulated miRNAs, and miR-668-3p was identified as a potential therapeutic target for AD. We found that the AD and Aβ1-42-induced models showed an increase in miR-668-3p and a decrease in oxidation resistance 1 (OXR1) expression. The luciferase analysis results revealed that miR-668-3p may play a role in AD development by targeting OXR1 and promoting intracellular oxidative stress by activating p53-p21 signaling. The final rescue experiment also confirmed that Aβ1-42-induction decreased cell proliferation, increased apoptosis, increased cell cycle arrest, and promoted oxidative stress. Tenovin-1 (TEN) enhanced the effect of Aβ1-42, and the miR-668-3p inhibitor partially alleviated it, although the effect of the miR-668-3p inhibitor was weakened by TEN.

Conclusions

MiR-668-3p negatively regulated OXR1 expression by targeting OXR1, affecting p53-p21 protein signaling, and regulating cell damage and oxidative stress induced by Aβ1-42. Therefore, miR-668-3p may be a potential therapeutic target for AD.

[Cocaine-amphetamine regulated transcript (CART) - promising omics breakthrough in the endocrinology]

BACKGROUND

The cocaine-amphetamine regulated transcript has been discovered long time ago (circa over 25 years ago) but still stays not enough investigated. Just during last five years scientist's society started providing interest to the genomic, proteomic and metabolic essence of the cocaine-amphetamine regulated transcript.

AIM

The evaluation of historical pathway and perspectives of the cocaine-amphetamine regulated transcript medical investigations.

MATERIALS AND METHODS

The literature search has been provided via Russian (eLibrary, CyberLeninka.ru) and international (PubMed, Cochrane Library) databases and among articles on Russian and English languages. The main criteria for article selection was free access and 2019-2021 years of publishing. Although the introduction is based on the articles published in 1989. The present article was created according to the federal project «Central and peripheral pathophysiological mechanisms of adipose tissue diseases and their clinical and hormonal manifestations патофизиологические механизмы развития болезней жировой ткани с учетом клинических и гормональных характеристик» (2020-2022)RESULTS AND CONCLUISON: It is necessary to keep on investigating genomic, proteomic and metabolomic markers because they contain important clues for successful resistance against human diseases. The 21st century is the era of transformation from simple clinical medicine to personalized science. For example, researches in the area of cocaine-amphetamine regulated transcript may result in invention of genetic medicine against dangerous metabolic diseases.

New uses of Melatonin as a Drug, a Review

Melatonin is a simple compound with a proper chemical name N-acetyl-5-methoxy tryptamine and known as a hormone controlling circadian rhythm. Humans produce melatonin at night which is the reason for sleeping in the night and awakening over the day. Melatonin interacts with melatonin receptors MT1 and MT2 but it was also revealed that melatonin is a strong antioxidant and it also has a role in regulation of cell cycle. Currently, melatonin is used as a drug for some types of sleep disorder but the recent research points to the fact that melatonin can also serve for the other purposes including prophylaxis or therapy of lifestyle diseases, cancer, neurodegenerative disorders and exposure to chemicals. This review summarizes basic facts and direction of the current research on melatonin. The actual literature was scrutinized for the purpose of this review.

Irisin Acts via the PGC-1α and BDNF Pathway to Improve Depression-like Behavior

Depression is the most prevalent psychiatric disorder experienced by the world's population. Mechanisms associated with depression-like behavior have not been fully investigated. Among the therapeutic solution for depression, exercise is considered an important regulator attenuating depressive neuropathology. Exercise has been reported to boost the secretion of myokines such as irisin and myostatin in skeletal muscles. Myokines secreted during exercise are involved in various cellular responses including the endocrine and autocrine systems. Especially, irisin as a cleaved version of fibronectin domain-containing protein 5 has multiple functions such as white fat-browning, energy expenditure increase, anti-inflammatory effects, and mitochondrial function improvement in both systemic circulation and central nervous system. Furthermore, irisin activates energy metabolism-related signaling peroxisome proliferator-activated receptor-gamma coactivator-1 alpha and memory formation-related signaling brain-derived neurotrophic factor involved in depression. However, the role and mechanism of irisin in depression disorder is not obvious until now. Here, we review recent evidences regarding the therapeutic effect of irisin in depression disorder. We suggest that irisin is a key molecule that suppresses several neuropathological mechanisms involved in depression.

Energy metabolism in major depressive disorder: Recent advances from omics technologies and imaging

Major depressive disorder (MDD) is a serious psychiatric disorder that associated with high rate of disability and increasing suicide rate, and the pathogenesis is still unclear. Many researches showed that the energy metabolism of patients with depression is impaired, which may be the direction of depression treatment. In this review, we focus on the "omics" technologies such as genomics, proteomics, transcriptomics and metabolomics, as well as imaging, and the progress on energy metabolism of MDD. These findings indicate that abnormal energy metabolism is one of the important mechanisms for the occurrence and development of depression. Although the research on various mechanisms of depression is still ongoing, the rapid development of new technologies and the joint use of various technologies will help to clarify the pathogenesis of depression and explore efficient diagnosis and treatment methods.