The coordinated alteration of freely circulating and EV-associated miRNAs highlight the potential contribution of miRNA-mediated regulation to premature HPG axis activation and provides a framework for further investigation of the molecular mechanisms underlying pubertal disorders.
Abstract
Background Central precocious puberty (CPP) results from premature activation of the hypothalamic–pituitary–gonadal (HPG) axis. While hormonal mechanisms underlying pubertal initiation are well established, the molecular regulatory processes accompanying altered pubertal timing remain incompletely understood. Circulating microRNAs (miRNAs), detectable either freely or within extracellular vesicles (EVs), represent a molecular layer of post-transcriptional regulation associated with pubertal development. Methods Serum samples from female patients diagnosed with CPP and age-matched healthy female controls were analyzed by small RNA sequencing to identify differentially expressed miRNAs. Selected miRNAs were validated by quantitative real-time PCR (RT–qPCR) in an expanded cohort using serum RNA and RNA isolated from serum-derived EVs. Functional enrichment analysis was conducted using experimentally validated miRNA target genes. Results Small RNA sequencing identified ten miRNAs with significantly altered expression levels in CPP (adjusted p-value < 0.05, |log2FC| > 0.5). Pathway enrichment analysis highlighted biological processes related to neurodevelopment, growth regulation and cellular maturation. RT–qPCR validation confirmed reduced serum expression of miR-125a-5p, miR-125b-5p and miR-99b-5p in CPP patients. All selected miRNAs were detectable in serum-derived EVs. Notably, miR-148a-3p exhibited a statistically significant increase specifically within the EV-associated fraction of CPP samples. Conclusions This study provides a comprehensive analysis of the circulating miRNA profile in female patients with CPP. The coordinated alteration of freely circulating and EV-associated miRNAs highlight the potential contribution of miRNA-mediated regulation to premature HPG axis activation and provides a framework for further investigation of the molecular mechanisms underlying pubertal disorders.
Pilot study results suggest potential miRNAs and their target pathway links with PCOS that need validation in larger cohorts for diagnostic or therapeutic applications need validation in larger cohorts for diagnostic or therapeutic applications.
Polycystic ovary syndrome (PCOS) is one of the most prevalent endocrine disorders in reproductive-aged women and is associated with reproductive dysfunction, metabolic abnormalities, and chronic low-grade inflammation. Emerging evidence highlights the role of circulating exosomal inflammatory cytokines and non-coding RNAs (ncRNAs) in PCOS pathogenesis. This case-control study aimed to investigate the expression of exosomal mRNA expression levels of IL-6 and TGF-β1, and selected long non-coding RNAs (MALAT1, NEAT1, H19, GAS5, and HOTAIR) in women with PCOS and to elucidate the associated lncRNA-miRNA-mRNA regulatory network. Exosomes were isolated from serum samples of PCOS and healthy subjects using a commercial exosome isolation kit. Exosomes were characterized by FESEM, DLS, zeta potential analysis, and flow cytometry, followed by RNA extraction and cDNA synthesis. Bioinformatic analyses were performed to construct regulatory networks, followed by molecular docking to evaluate the potential interactions between lncRNAs and miRNAs. A heatmap illustrating gene expression patterns was generated in R using the pheatmap package. Characterization of the isolated vesicles confirmed a spherical morphology, nanoscale dimensions, and the presence of exosomal surface markers. The exosomal mRNA expression levels of IL-6 and TGF-β1 were significantly upregulated in patients with PCOS. Among the lncRNAs analyzed, GAS5, NEAT1, and H19 were significantly increased, whereas MALAT1 and HOTAIR were markedly decreased. Network analysis identified miR-146a-5p and miR-29b-3p as key regulatory hubs associated with IL-6 and TGF-β1 mRNA expression. Molecular docking suggested a higher likelihood of stable binding, particularly for the H19/miR-146a-5p and NEAT1/miR-29b-3p complexes. These findings may suggest a potential role for dysregulation of the exosomal lncRNA-miRNA-mRNA regulatory axis, particularly involving IL-6 and TGF-β1 mRNA expression, in the inflammatory processes associated with PCOS. In addition, circulating exosomal ncRNAs and inflammation-related factors may represent potential non-invasive biomarkers and possible therapeutic targets for PCOS. However, these associations require further functional and validation studies.
Kamand Adhami, Mohammad Karimian, Zahra Karimian· Scientific Reports· 0 citations
Background: Frontotemporal dementia (FTD) is a neurodegenerative disease that shares numerous clinical features with other forms of dementia. In this context, non-coding RNAs, specifically microRNAs (miRNAs), represent a promising tool for differential diagnosis. Since these miRNAs can be isolated from circulating extracellular vesicles (EVs) in peripheral blood, they provide a direct insight into FTD-specific molecular processes. Consequently, while EV-contained miRNAs hold potential as disease-specific biomarkers, investigating their relative target genes can help elucidate their precise functional roles. Aim: This work aimed to identify a specific miRNA signature to better characterize FTD pathology. Methods: Building on a previous Next-Generation Sequencing (NGS) analysis, three candidate miRNAs were selected for validation in both EVs and peripheral blood mononuclear cells (PBMCs) of FTD patients. Subsequently, the predicted target genes of two of these miRNAs were validated in PBMCs to assess their expression levels. Results: Our findings revealed that miR-365a-3p and miR-212 were significantly down-regulated in FTD. Conclusions: Together with their target genes, these miRNAs are involved in cell cycle and apoptotic pathways, suggesting a potential role in the pathological mechanisms of the disease.
Evelyne Minucchi, F. Dragoni, R. Di Gerlando et al.· Genes· 0 citations
Background The placenta has a unique transcriptomic profile, including microRNAs that are secreted into maternal circulation throughout pregnancy. MicroRNAs are small, non-coding RNA that post-transcriptionally regulate gene expression. Spontaneous preterm birth (sPTB) is associated with substantial differences in both placental pathophysiology and placental gene expression compared to term birth. We aimed to generate microRNA signatures of sPTB and map them to target genes using a microRNA–mRNA network. Methods This study was conducted within the Conditions Affecting Neurocognitive Development and Learning in Early childhood (CANDLE) study. Placental samples were collected at delivery, and RNA was isolated for mRNA and microRNA sequencing. To investigate sPTB, this study excluded placental samples of participants with iatrogenic indications for PTB or induced labor. We examined differences in microRNA expression in participants who delivered before 37 weeks (N=35) compared to term participants (N=404) in a series of covariate-adjusted linear regression models. We used paired placental microRNA and mRNA expression data from this cohort to validate associations between computationally predicted microRNA–mRNA pairs and establish a microRNA–mRNA network. Results Expression of 7 microRNAs were increased in sPTB (FDR<0.05) and were inversely correlated with sPTB-associated genes involved in immune signaling. Expression of 12 microRNAs were decreased in sPTB, including 4 members of the maternally expressed chromosome 14 microRNA cluster (miR-376a-3p, miR-376c-3p, miR-377-3p, and miR-381-3p). These microRNAs were predicted to negatively regulate oxidative phosphorylation genes that were increased in sPTB. The associations between miR-376c-3p and miR-377-3p and oxidative phosphorylation were confirmed in microRNA knockdown experiments. Conclusions This study highlights potential biological mechanisms by which placental microRNA dysfunction might contribute to sPTB and highlights putative sPTB biomarkers that may be detectable in maternal circulation.
Mariana Parenti, Elizabeth M. Kennedy, Evan J. Firsick et al.· bioRxiv· 0 citations
BACKGROUND
Central precocious puberty (CPP) results from premature activation of the hypothalamic-pituitary-gonadal axis, causing early sexual development and related health risks. Stigmasterol (ST), a natural phytosterol with diverse pharmacological activities, has not been fully evaluated for CPP.
METHODS
This study integrated network pharmacology, molecular docking, and molecular dynamics simulations to identify ST targets in CPP. Experimental validation used an N-Methyl aspartic acid-induced CPP rat model and high-glucose high-fat-stimulated GT1-7 hypothalamic neurons. Techniques included histology, ELISA, qPCR, western blot, and flow cytometry.
RESULTS
In silico analyses demonstrated favorable binding of ST to core proteins within the IGF-1/PI3K/Akt/mTOR signaling pathway. In vivo, ST treatment significantly delayed vaginal opening, reduced serum levels of estradiol and testosterone, and ameliorated pathological abnormalities in uterine and ovarian tissues. At the molecular level, ST suppressed the hypothalamic overactivation of the IGF-1/PI3K/Akt/mTOR pathway and attenuated neuronal damage and apoptosis. In vitro, ST inhibited HGHF-induced proliferation, inflammatory cytokine release, and apoptosis in GT1-7 cells, while concurrently modulating the expression of key puberty-related genes and proteins, including those within the Kisspeptin/GnRH axis. Conversely, pharmacological reactivation of PI3K signaling with the agonist 740YP attenuated selected protective effects the protective effects of ST, supporting the functional involvement the PI3K/Akt/mTOR pathway in mediating these benefits.
CONCLUSIONS
Stigmasterol exhibits significant therapeutic effects against CPP by concurrently targeting the IGF-1/PI3K/Akt/mTOR and Kisspeptin/GnRH signaling pathways. These findings provide robust preclinical evidence supporting ST as a promising multi-targeted natural candidate for CPP management.
Lin Dong, Yan Xing, Xiaoning Li et al.· Biochimica et Biophysica Act...· 0 citations
AIM
MicroRNAs are key regulators of metabolic homeostasis, circulating both freely in serum and encapsulated within exosomes, but a direct comparative analysis of their diagnostic potential in prediabetes remains unexplored.
METHODS
We conducted a cohort study involving individuals with prediabetes (n = 25), newly diagnosed Type 2 Diabetes Mellitus (n = 15), persisting Type 2 Diabetes Mellitus (n = 25), and age-, sex-, and BMI-matched normoglycemic controls (n = 25). RNA was isolated from paired whole serum and serum-derived exosomes, and RT-qPCR was performed to quantify differentially expressed miRNAs (miR-128-3p, miR-15b-5p, miR-6838-5p, miR-195-5p, and miR-424-5p). Diagnostic power of candidate miRNAs was determined using ROC curve analysis.
RESULTS
Distinct miRNA signatures were identified in whole serum and exosomal fractions. miR-195-5p and miR-6838-5p were consistently and significantly upregulated in the prediabetes cohort. Exosomal miRNAs also exhibited distinct changes in both prediabetes and n-T2DM. Their diagnostic performance demonstrated significant ability to differentiate between individuals with prediabetes and normoglycemia.
CONCLUSION
Our findings indicate that analysis of total serum miRNAs provides a more sensitive and robust approach for identifying individuals with prediabetes, which correlates with the exosomal fraction. Hence, we can infer that miR-195-5p and miR-6838-5p are novel, high-performance circulatory biomarkers detecting T2DM, paving the way for improved risk stratification and preventive strategies.
A. Mendonça, J. Kumar, Sujatha Sundaresan· Diabetes Research and Clinic...· 0 citations
