Abnormal expression of long non-coding RNAs RMRP, CTC-487M23.5, and DGCR5 in the peripheral blood of patients with Bipolar disorder

Long non-coding RNAs in bipolar disorder

Bipolar disorder is characterized by alternating episodes of mania or hypomania and depression, encompassing various forms such as cyclothymia, bipolar I disorder, and bipolar II disorder. Manic periods present with increased energy and decreased sleep, whereas depressive episodes involve poor energy and extended sleep duration. Despite the availability of treatments, approximately 30% of patients with bipolar disorder are drug resistant and require alternative strategies. Recent research highlights the role of long noncoding RNAs (lncRNAs) as potential biomarkers for bipolar disorder, aiding in distinguishing it from other mood disorders and improving diagnostic accuracy. LncRNAs such as GAS5 and FOXD3-AS1 are downregulated in bipolar disorder patients, suggesting their utility as diagnostic tools. LncRNAs regulate gene expression through interactions with DNA, RNA, and proteins, influencing various biological processes. Studies have identified several lncRNAs linked to bipolar disorder, including lincRNA-p21, lincRNA-ROR, and lincRNA-PINT. These findings underscore the potential of lncRNAs as biomarkers and therapeutic targets, facilitating more personalized treatment strategies. This review explores the diagnostic and therapeutic potential of lncRNAs in bipolar disorder, aiming to enhance the current understanding and management of this condition.

Up-regulation of HOXA-AS2 and MEG3 long non-coding RNAs acts as a potential peripheral biomarker for bipolar disorder

Bipolar disorder (BD) is a psychiatric condition that is frequently misdiagnosed and linked to inadequate treatment. Long non-coding RNAs (lncRNAs) have lately gained recognition as crucial genetic elements and are now regarded as regulatory mechanisms in the neurological system. Our objective was to measure the quantities of HOXA-AS2 and MEG3 ncRNA transcripts. HOXA-AS2 and MEG3 ncRNA levels were checked in the peripheral blood of 50 type I BD and 50 control samples by real-time PCR. Furthermore, we conducted ROC curve analysis and correlation analysis to examine the association between gene expression and specific clinical characteristics in instances with BD. Additionally, a computational study was performed to investigate the binding sites of miRNAs on the HOXA-AS2 and MEG3 lncRNAs. BD subjects showed a significant increase in the expression of HOXA-AS2 and MEG3 compared to controls. The lncRNAs HOXA-AS2 and MEG3 have an area under the ROC curve (AUC) values of 0.70 and 0.71, respectively. There was a significant correlation between the expression levels of ncRNAs HOXA-AS2 and MEG3 in the peripheral blood of patients with BD and occupation scores. The data presented indicate a potential correlation between the expression of HOXA-AS2 and MEG3 lncRNAs with an elevated risk of BD. Furthermore, these lncRNAs may be linked to several molecular pathways. Our findings indicate that the amounts of lncRNAs HOXA-AS2 and MEG3 in transcripts might be a promising potential biomarker for patients with BD.

The Association and Prognostic Implications of Long Non-Coding RNAs in Major Psychiatric Disorders, Alzheimer's Diseases and Parkinson's Diseases: A Systematic Review

The prevalence of psychiatric disorders and neurodegenerative diseases is steadily increasing, placing a significant burden on both society and individuals. Given the intricate and multifaceted nature of these diseases, the precise underlying mechanisms remain elusive. Consequently, there is an increasing imperative to investigate the mechanisms, identify specific target sites for effective treatment, and provide for accurate diagnosis of patients with these diseases. Numerous studies have revealed significant alterations in the expression of long non-coding RNAs (lncRNAs) in psychiatric disorders and neurodegenerative diseases, suggesting their potential to increase the probability of these diseases. Moreover, these findings propose that lncRNAs could be used as highly valuable biomarkers in diagnosing and treating these diseases, thereby offering novel insights for future clinical interventions. The review presents a comprehensive summary of the origin, biological functions, and action mechanisms of lncRNAs, while exploring their implications in the pathogenesis of psychiatric disorders and neurodegenerative diseases and their potential utility as biomarkers.

Potential Early Effect Biomarkers for Ambient Air Pollution Related Mental Disorders

Air pollution is one of the greatest environmental risks to health, with 99% of the world's population living where the World Health Organization's air quality guidelines were not met. In addition to the respiratory and cardiovascular systems, the brain is another potential target of air pollution. Population- and experiment-based studies have shown that air pollution may affect mental health through direct or indirect biological pathways. The evidence for mental hazards associated with air pollution has been well documented. However, previous reviews mainly focused on epidemiological associations of air pollution with some specific mental disorders or possible biological mechanisms. A systematic review is absent for early effect biomarkers for characterizing mental health hazards associated with ambient air pollution, which can be used for early warning of related mental disorders and identifying susceptible populations at high risk. This review summarizes possible biomarkers involved in oxidative stress, inflammation, and epigenetic changes linking air pollution and mental disorders, as well as genetic susceptibility biomarkers. These biomarkers may provide a better understanding of air pollution's adverse effects on mental disorders and provide future research direction in this arena.

Long Noncoding RNA VLDLR-AS1 Levels in Serum Correlate with Combat-Related Chronic Mild Traumatic Brain Injury and Depression Symptoms in US Veterans

More than 75% of traumatic brain injuries (TBIs) are mild (mTBI) and military service members often experience repeated combat-related mTBI. The chronic comorbidities concomitant with repetitive mTBI (rmTBI) include depression, post-traumatic stress disorder or neurological dysfunction. This study sought to determine a long noncoding RNA (lncRNA) expression signature in serum samples that correlated with rmTBI years after the incidences. Serum samples were obtained from Long-Term Impact of Military-Relevant Brain-Injury Consortium Chronic Effects of Neurotrauma Consortium (LIMBIC CENC) repository, from participants unexposed to TBI or who had rmTBI. Four lncRNAs were identified as consistently present in all samples, as detected via droplet digital PCR and packaged in exosomes enriched for CNS origin. The results, using qPCR, demonstrated that the lncRNA VLDLR-AS1 levels were significantly lower among individuals with rmTBI compared to those with no lifetime TBI. ROC analysis determined an AUC of 0.74 (95% CI: 0.6124 to 0.8741; p = 0.0012). The optimal cutoff for VLDLR-AS1 was ≤153.8 ng. A secondary analysis of clinical data from LIMBIC CENC was conducted to evaluate the psychological symptom burden, and the results show that lncRNAs VLDLR-AS1 and MALAT1 are correlated with symptoms of depression. In conclusion, lncRNA VLDLR-AS1 may serve as a blood biomarker for identifying chronic rmTBI and depression in patients.