CircELK4 Contributes to Lupus Nephritis by Acting as a miR-27b-3p Sponge to Regulate STING/IRF3/IFN-I Signaling.

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease and a common complication of SLE is lupus nephritis (LN) during which lupus autoantibodies and proinflammatory cytokines attack the kidney and cause renal dysfunction. The current treatments to LN are limited due to a poor understanding of the pathogenesis. Here, we studied the molecular mechanisms of LN by investigating the function of circELK4/miR-27b-3p axis. MRL/lpr mice and LPS-treated HK-2 cells were used as the mouse model and cell model of LN, respectively. Blood samples were collected from LN patients. qRT-PCR and western blot were used to measure expression levels of circELK4, miR-27b-3p, apoptosis-related proteins, cytokines, and STING/IRF-3/IFN-I signaling. ELISA was performed to examine levels of cytokines including IL-6 and TNF-α. H&E staining was used to examine kidney morphology. TUNEL staining and flow cytometry were used to determine cell apoptosis. Dual luciferase activity assay and RNA pull down were employed to validate the interactions of circELK4/miR-27b-3p and miR-27b-3p/STING. CircELK4 was elevated in LN mice, patients, and LPS-treated HK-2 cells. Knockdown of circELK4 attenuated renal injury in LN mice and LPS-induced HK-2 cell injury. CircELK4 directly bound to miR-27b-3p while miR-27b-3p targeted STING. Moreover, overexpression of circELK4 could partially reverse the effects of miR-27b-3p mimics on cell apoptosis and inflammation. Furthermore, circELK4/miR-27b-3p regulated renal cell damage via modulating STING/IRF3/IFN-I signaling. CircELK4 contributes to renal injury by promoting inflammation and cell apoptosis via acting as a miR-27b-3p sponge to modulate STING/IRF3/IFN-I signaling in LN.

[Hazardous environmental factors causing renal damage in children].

Hazardous environmental factors invade the body through multiple routes, including ingestion, inhalation and absorption by contact with the skin and mucous membrane. They are from various sources and soil, water, air, building and decorative materials, foods and daily necessities are the main carriers. According to their physical and chemical properties and morphological characteristics, these hazardous factors are classified as metals, inorganic matter, organic matter, radioactive substances, biological toxins, viruses, bacteria, mycoplasmas, chlamydiae and parasites. They cause diseases through blood and urine and also have kidney susceptibility. This article suggests that pediatricians should fully understand the characteristics and seriousness of hazardous environmental factors that cause renal damage, and pay attention to the prevention and control of these factors so as to minimize renal damage in children.

[Relationship of 24-hour ambulatory blood pressure and rennin-angiotensin-aldosterone system in children with primary nephrotic syndrome].

OBJECTIVE: To investigate the changes of blood pressure by 24-hour ambulatory blood pressure (ABP) monitoring in children with primary nephrotic syndrome (PNS) and explore the relationship of the changes in blood pressure with rennin-angiotensin-aldosterone system (RAAS) in these children. METHODS: ABP and casual blood pressure (CBP) monitoring were performed in 114 children with PNS. Plasma levels of rennin activity (PRA), angiotensin II (AngII) and aldosterone (ALD) were measured. The correlation of plasma levels of PRA, AngII and ALD with ABP was evaluated. RESULTS: Of the 114 children with PNS, 101 (88.6%) presented elevated blood pressure. Mild or severe masked hypertension was found in 45 children (39.5%). Eighty (70.2%) children showed non-dipper blood pressure. The index and load of systolic blood pressure were higher than those of diastolic blood pressure. The blood pressure index and blood pressure load during sleep were higher than those during wakefulness. The boy presented higher diastolic blood pressure index and load than girls. Decubitus blood PRA, AngII and ALD levels in children with PNS were significantly higher than normal controls. The group with elevated blood pressure presented significantly higher decubitus blood PRA, AngII and ALD levels than the group with normal blood pressure. AngII level was significantly positively correlated with the index and load of both systolic blood pressure and diastolic blood pressure. CONCLUSIONS: The children with PNS present a high incidence of hypertension, with a large percentage of masked hypertension and non-dipper blood pressure. Systolic blood pressure increases more significantly than diastolic blood pressure. Blood pressure during sleep increases more significantly than that during wakefulness. Diastolic blood pressure increases more significantly in boys than in girls. RAAS activity is elevated and the elevated RAAS activity might increase the blood pressure mainly by AngII in children with PNS.