Association between Behavioural Risks and Alzheimer's Disease: Elucidated with an Integrated Analysis of Gene Expression Patterns and Molecular Mechanisms

Identification of lncRNA in circulating exosomes as potential biomarkers for MCI among the elderly

BACKGROUND

The abnormal expression of lncRNA in elderly patients with mild cognitive impairment (MCI), and the ability of exosomes to stably carry non-coding RNAs provide a reliable physiological basis for exosomal lncRNA in plasma as a biomarker of MCI.

METHODS

This case-control study enrolled 155 patients with MCI and 155 healthy controls from a community-based population aged≥60 years. The expression profiles of lncRNA and mRNA in plasma exosomes were analyzed and validated using high-throughput RNA sequencing and qRT-PCR. Pathway enrichment analysis were performed on differentially expressed transcripts to screen for target lncRNAs and genes. Multivariate logistic regression models were used to construct clinical predictive models. The receiver operating characteristic curve was used to analyze the predictive value, with an 184-sample external database validated.

RESULTS

132 lncRNAs and 459 mRNAs were significantly changed in plasma exosomes of MCI patients compared to healthy controls. LINC001380, ENST00000484033, and ENST00000531087 were screened as candidate exo-lncRNAs for predicting MCI. In logistic regression models, odds ratios and 95%CI for target exo-IncRNAs in MCI patients compared to healthy controls were 1.15(1.03-1.28) for LINC001380, 1.21(1.10-1.34) for ENST00000484033, and 1.23(1.08-1.40) for ENST00000531087, respectively. ROC curve analysis showed that the AUC of the combined predicted probability of target lncRNAs was 70.0 %(64.1 %-76.0 %). In the external database, the AUC for the target genes ATP2A2 and PSEN1 was 69.5 %(61.8 %-77.15 %).

CONCLUSION

This study provided evidence for the specific expression of plasma exosomal lncRNAs in MCI and its possible biological mechanism. The combined detection of the expression levels of lncRNA-LINC001380, lncRNA-ENST00000484033, and lncRNA-ENST00000531087 in plasma exosomes may provide early diagnosis and prevention of cognitive impairment.

Insights Into Retinal Pathologies in Neurological Disorders: A Focus on Parkinson's Disease, Multiple Sclerosis, Amyotrophic Lateral Sclerosis, and Alzheimer's Disease

Neurological diseases are central nervous system (CNS) disorders affecting the whole body. Early diagnosis of the diseases is difficult due to the lack of disease-specific tests. Adding new biomarkers external to the CNS facilitates the diagnosis of neurological diseases. In this respect, the retina has a common embryologic origin with the CNS. Retinal imaging technologies including optical coherence tomography (OCT) can be used in the understanding and processual monitoring of neurological diseases. Retinal imaging has been recently recognized as a potential source of biomarkers for neurological diseases, increasing the number of studies in this direction. In this review, the association of retinal abnormalities with Parkinson's disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), and Alzheimer's disease (AD) is explained. Structural and functional abnormalities in retina as a predictive marker may facilitate early diagnosis of diseases. Although not all retinal abnormalities are predictive of neurologic diseases, changes in the retinal layers including retinal pigment epithelium and plexiform layers should suggest the risk of PD, MS, ALS, and AD.

Extracellular vesicle and CRISPR gene therapy: Current applications in Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and Huntington's disease

Neurodegenerative diseases are characterized by progressive deterioration of the nervous system. Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD) are prominently life-threatening examples of neurodegenerative diseases. The complexity of the pathophysiology in neurodegenerative diseases causes difficulties in diagnosing. Although the drugs temporarily help to correct specific symptoms including memory loss and degeneration, a complete treatment has not been found yet. New therapeutic approaches have been developed to understand and treat the underlying pathogenesis of neurodegenerative diseases. With this purpose, clustered-regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas) technology has recently suggested a new treatment option. Editing of the genome is carried out by insertion and deletion processes on DNA. Safe delivery of the CRISPR/Cas system to the targeted cells without affecting surrounding cells is frequently investigated. Extracellular vesicles (EVs), that is exosomes, have recently been used in CRISPR/Cas studies. In this review, CRISPR/Cas and EV approaches used for diagnosis and/or treatment in AD, PD, ALS, and HD are reviewed. CRISPR/Cas and EV technologies, which stand out as new therapeutic approaches, may offer a definitive treatment option in neurodegenerative diseases.

Butylated Hydroxytoluene (BHT) Protects SH-SY5Y Neuroblastoma Cells from Ferroptotic Cell Death: Insights from In Vitro and In Vivo Studies

Ferroptosis is a special kind of programmed cell death that has been implicated in the pathogenesis of a large number of human diseases. It involves dysregulated intracellular iron metabolism and uncontrolled lipid peroxidation, which together initiate intracellular ferroptotic signalling pathways leading to cellular suicide. Pharmacological interference with ferroptotic signal transduction may prevent cell death, and thus patients suffering from ferroptosis-related diseases may benefit from such treatment. Butylated hydroxytoluene (BHT) is an effective anti-oxidant that is frequently used in oil chemistry and in cosmetics to prevent free-radical-mediated lipid peroxidation. Since it functions as a radical scavenger, it has previously been reported to interfere with ferroptotic signalling. Here, we show that BHT prevents RSL3- and ML162-induced ferroptotic cell death in cultured human neuroblastoma cells (SH-SY5Y) in a dose-dependent manner. It prevents the RSL3-induced oxidation of membrane lipids and normalises the RSL3-induced inhibition of the intracellular catalytic activity of glutathione peroxidase 4. The systemic application of BHT in a rat Alzheimer's disease model prevented the upregulation of the expression of ferroptosis-related genes. Taken together, these data indicate that BHT interferes with ferroptotic signalling in cultured neuroblastoma cells and may prevent ferroptotic cell death in an animal Alzheimer's disease model.

Alzheimer, Parkinson, dementia, and phytochemicals: insight review

Alzheimer's, Parkinson's, and dementia are the leading neurodegenerative diseases that threaten the world with the aging population. Although the pathophysiology of each disease is unique, the steps to be taken to prevent diseases are similar. One of the changes that a person can make alone is to gain the habit of an antioxidant-rich diet. Phytochemicals known for their antioxidant properties have been reported to prevent neurodegenerative diseases in various studies. Phytochemicals with similar chemical structures are grouped. Accordingly, there are two main groups of phytochemicals, flavonoid and non-flavonoid. Various in vitro and in vivo studies on phytochemicals have proven neuroprotective effects by increasing cognitive function with their anti-inflammatory and antioxidant mechanisms. The purpose of this review is to summarize the in vitro and in vivo studies on phytochemicals with neuroprotective effects and to provide insight.