Inter-correlation of lncRNA THRIL with microRNA-34a and microRNA-125b and their relationship with childhood asthma risk, severity, and inflammation

Unveiling the hidden power of noncoding RNAs in pediatric respiratory diseases

Respiratory diseases in children are common health problems that significantly impact their quality of life and health status, and this has its own unique challenges compared to adults. A growing body of research has focused on epigenetic mechanisms that relate with the development of various diseases, such as pediatric respiratory diseases. Noncoding RNAs (ncRNAs), especially long noncoding RNAs, microRNA, and circular RNA, are reported to play a regulatory role in pediatric respiratory diseases whose mutations or aberrant expressions are strongly associated with the development of these diseases. In this review, we mainly discussed the functions of these three ncRNAs in pediatric respiratory diseases.

Potential Impact of SOD2 (rs4880; p.Val16Ala) Variant with the Susceptibility for Childhood Bronchial Asthma

Oxidative stress is a sophisticated situation that orignates from the accumulation of reactive free radicals within cellular compartments. The antioxidant mechanism of the MnSOD enzyme facilitates the removal of these lethal oxygen species from cellular components. The main goal of this pertained work is to study the contribution of the SOD2 (rs4880; p.Val16Ala) variant to the development of bronchial asthma among children. The study's design was carried out based on a total of 254 participants including 127 asthmatic children (91 atopic and 36 non-atopic) along with 127 unrelated healthy controls. Allelic discrimination analysis was executed using the T-ARMS-PCR protocol. This potential variant conferred a significant association with decreased risk of bronchial asthmatic children under allelic (OR = 0.56, P-value = 0.002), recessive (OR = 0.32, P-value = 0.011), and dominant (OR = 0.51, P-value = 0.040) models. Additionally, atopic and non-atopic asthmatic children indicated a protection against bronchial asthma development under allelic, and dominant models (p-value < 0.05). Our findings suggested that the SOD2*rs4880 variant was correlated with decreased risk of childhood bronchial asthma.

Heavy metal levels are positively associated with serum periostin and miRNA-125b levels, but inversely associated with miRNA-26a levels in pediatric asthma cases. A case-control study

BACKGROUND

The study investigated heavy metals levels [urinary cadmium (U-Cd), erythrocytic cadmium (E-Cd), urinary arsenic (U-As), and whole blood lead (WB-Pb)] in children with bronchial asthma (BA) and tested their associations with serum periostin, miRNA-125b and miRNA-26a levels, and with asthma severity clinically and laboratory [blood eosinophils count (BEC) and serum total immunoglobin E (IgE)]. Also, we tested cut-off points, for the studied parameters, to distinguish BA cases from healthy children.

METHODS

This case-control study included 158 children divided into control group; n = 72 and BA group; n = 86. Heavy metals were measured by an inductively coupled plasma-optical emission spectrophotometer. Serum periostin and IgE levels were measured by their corresponding ELISA kits. miRNAs relative expressions were estimated by RT-qPCR using the 2-ΔΔCT method.

RESULTS

Heavy metals, serum periostin, and miR-125b levels were significantly high in BA group (p < 0.001). Heavy metals levels correlated positively with serum periostin, miR-125b and IgE levels, BEC, and asthma severity. The reverse was observed regarding serum miR-26a levels. Receiver operating characteristics (ROC) curve analysis showed good to excellent abilities of U-Cd, E-Cd, U-As, WB-Pb, serum periostin, miRNA-125b, and miRNA - 26a, and total IgE levels to distinguish BA cases from healthy children.

CONCLUSIONS

Heavy metal toxicity in children is associated with BA severity, increased serum periostin and miRNA-125b levels, and decreased miRNA-26a levels. Specific measures to reduce children's exposure to heavy metals should be taken. Future research should consider blocking miRNA-125b action or enhancing miRNA-26a action to manage BA cases.

The Roles of MicroRNAs in Asthma and Emerging Insights into the Effects of Vitamin D3 Supplementation

Asthma is one of the most common chronic non-communicable diseases worldwide, characterized by variable airflow limitation secondary to airway narrowing, airway wall thickening, and increased mucus resulting from chronic inflammation and airway remodeling. Current epidemiological studies reported that hypovitaminosis D is frequent in patients with asthma and is associated with worsening the disease and that supplementation with vitamin D3 improves asthma symptoms. However, despite several advances in the field, the molecular mechanisms of asthma have yet to be comprehensively understood. MicroRNAs play an important role in controlling several biological processes and their deregulation is implicated in diverse diseases, including asthma. Evidence supports that the dysregulation of miR-21, miR-27b, miR-145, miR-146a, and miR-155 leads to disbalance of Th1/Th2 cells, inflammation, and airway remodeling, resulting in exacerbation of asthma. This review addresses how these molecular mechanisms explain the development of asthma and its exacerbation and how vitamin D3 may modulate these microRNAs to improve asthma symptoms.