MiR-29b expression is altered in crescent formation of HSPN and accelerates Ang II-induced mesangial cell activation

NKRF in Cardiac Fibroblasts Protects against Cardiac Remodeling Post-Myocardial Infarction via Human Antigen R

Myocardial infarction (MI) remains the leading cause of death worldwide. Cardiac fibroblasts (CFs) are abundant in the heart and are responsible for cardiac repair post-MI. NF-κB-repressing factor (NKRF) plays a significant role in the transcriptional inhibition of various specific genes. However, the NKRF action mechanism in CFs remains unclear in cardiac repair post-MI. This study investigates the NKRF mechanism in cardiac remodeling and dysfunction post-MI by establishing a CF-specific NKRF-knockout (NKRF-CKO) mouse model. NKRF expression is downregulated in CFs in response to pathological cardiac remodeling in vivo and TNF-α in vitro. NKRF-CKO mice demonstrate worse cardiac function and survival and increased infarct size, heart weight, and MMP2 and MMP9 expression post-MI compared with littermates. NKRF inhibits CF migration and invasion in vitro by downregulating MMP2 and MMP9 expression. Mechanistically, NKRF inhibits human antigen R (HuR) transcription by binding to the classical negative regulatory element within the HuR promoter via an NF-κB-dependent mechanism. This decreases HuR-targeted Mmp2 and Mmp9 mRNA stability. This study suggests that NKRF is a therapeutic target for pathological cardiac remodeling.

Chlorogenic Acid Prevents Microglia-Induced Neuronal Apoptosis and Oxidative Stress under Hypoxia-Ischemia Environment by Regulating the MIR497HG/miR-29b-3p/SIRT1 Axis

Background

Chlorogenic acid (CGA) is a polyphenolic compound with antioxidant and anti-inflammatory properties. CGA has been shown to improve neuroinflammation. This study is aimed at elucidating the exact mechanism by which CGA reduces neuroinflammation.

Methods

Oxygen and glucose deprivation (OGD) was utilized to treat BV2 microglia and HT-22 hippocampal neurons to engineer an in vitro model of hypoxic ischemia reperfusion. The levels of inflammatory factors (IL-1β, IL-6, TNF-α, IL-4, and IL-10) and oxidative stress factors (MDA, SOD, and GSH-PX) in microglia were determined by ELISA kits. The neuron proliferation was assessed by CCK-8 assay, and LDH kit was used to determine LDH release in neurons. The fluorescent dye DCF-DA was employed to measure ROS levels in neurons. Correlation of MIR497HG, miR-29b-3p, and SIRT1/NF-κB in neurons and microglia was determined by qRT-PCR. Expressions of inflammatory proteins (COX2, iNOS), oxidative stress pathways (Nrf2, HO-1), and apoptosis-related proteins (Bcl-2, Bax, caspase3, caspase8, and caspase9) in microglia or neurons were determined by western blot. The interactions between MIR497HG and miR-29b-3p, as well as between miR-29b-3p and SIRT1, were determined by dual luciferase assay and RIP assay.

Results

CGA attenuated OGD-mediated inflammation and oxidative stress in microglia and inhibited microglia-mediated neuronal apoptosis. CGA increased the levels of MIR497HG and SIRT1 and suppressed the levels of miR-29b-3p in BV2 and HT-22 cells. MIR497HG knockdown, miR-29b-3p upregulation, and SIRT1 inhibition inhibited CGA-mediated anti-inflammatory and neuronal protective functions. There is a targeting correlation between MIR497HG, miR-29b-3p, and Sirt1. MIR497HG sponges miR-29b-3p to regulate SIRT1 expression in an indirect manner.

Conclusion

CGA upregulates MIR497HG to curb miR-29b-3p expression, hence initiating the SIRT1/NF-κB signaling pathway and repressing OGD-elicited inflammation, oxidative stress, and neuron apoptosis.

A Review of the Mechanism of Vascular Endothelial Injury in Immunoglobulin A Vasculitis

Immunoglobulin A (IgA) vasculitis (IgAV), also known as Henoch-Schönlein purpura, is the most common form of childhood vasculitis. It is characterized by cutaneous hemorrhage, resulting from red blood cell leakage into the skin or mucosae, possibly caused by damage to small blood vessels. These acute symptoms usually disappear without treatment. Endothelial cells are distributed on the inner surfaces of blood vessels and lymphatic vessels, and have important functions in metabolism and endocrine function, as well as being the primary targets of external stimuli and endogenous immune activity. Injury to endothelial cells is a feature of IgA vasculitis. Endothelial cell damage may be related to the deposition of immune complexes, the activation of complement, inflammatory factors, and chemokines, oxidative stress, hemodynamics, and coagulation factors. Both epigenetic mechanisms and genetic diversity provide a genetic background for endothelial cell injury. Here, research on the role of endothelial cells in allergic IgA vasculitis is reviewed.

Let-7a Targeting TNFAPI3 Promotes Vascular Endothelial Cell Apoptosis of Pediatric Patients with Henoch–Schönlein Purpura via NF-κB Signaling Pathway

Objective

We aimed at exploring the role of let-7a in the pathogenesis of pediatric Henoch–Schönlein purpura (HSP) and its related mechanism.

Methods

Fifty-five pediatric HSP patients and 20 paired healthy controls were included. The expressions of let-7a and TNFAIP3 were detected by RT-qPCR or/and western blot. Vessel fibrinoid necrosis was evaluated in skin tissues by PTAH staining. The serum IgA level was measured by ELISA. Cells were transfected with let-7a inhibitor and/or TNFAIP3 siRNA, accompanied by pretreatment with NF-κB inhibitor PDTC or not. After being cultured in HSP serum, the changes in cell viability, cell apoptosis, apoptosis-related proteins, and NF-κB pathway-related proteins were detected by CCK8, flow cytometry, and western blot.

Results

The let-7a expression level was positively correlated with the serum IgA level and severity degree of vascular fibrinoid necrosis in HSP patients. Let-7a expression was significantly increased, whereas cell viability and TNFAIP3 expression were obviously decreased 48 h after HUVECs were incubated with HSP serum. Let-7a knockdown upregulated the cell viability, whereas it reduced the apoptotic ratio, apoptosis protein expressions (Bax/Bcl2 ratio, cleaved-caspase 3), and NF-κB pathway activation (reflected by reduced P65 nuclear translocation and p-IκBα expression) in HUVECs (all p < 0.05). The changes induced by let-7a knockdown were obviously reversed by TNFAIP3 siRNA transfection (p < 0.05). Besides, PDTC treatment remarkably diminished the anti-apoptosis effect of let-7a knockdown and pro-apoptosis effect of TNFAIP3 siRNA on HUVECs induced by HSP serum.

Conclusions

Let-7a knockdown significantly suppressed vascular endothelial cell apoptosis induced by HSP serum by targeting TNFAPI3 via NF-κB signaling pathway. Our findings provided a potential therapeutic target for the treatment of HSP.

The Efficacy of Tripterygium Glycosides Combined with LMWH in Treatment of HSPN in Children

Objective

This study aimed to explore the clinical efficacy and relevant mechanism of Tripterygium glycosides combined with low molecular weight heparin calcium (LMWH) in the treatment of Henoch–Schönlein purpura nephritis (HSPN) in children.

Methods

64 cases of children patients with HSPN treated at Qilu Hospital (Qingdao) from January 2015 to May 2020 were selected and randomly divided into the control group and the observation group and 32 cases in each group. Conventional medical treatment was applied in the two groups, besides which the control group was given LMWH while the observation group was given Tripterygium glycosides based on the control group. The clinical efficacy and the indexes of clinical symptoms of the two groups were compared. Immune globulin level, fibrinogen content (FIB), prothrombin time (PT), platelet level (PLT), and activated partial thromboplastin time (APTT) level of the two groups were compared before and after the treatment.

Results

The total effective rate in the observation group was significantly higher than that of the control group, and the recurrence rate in the observation group was lower than that in the control group. After treatment, urine red blood cell count and 24 h urine protein were obviously better than those of the control group. There was no statistically significant difference in PT between the two groups of children before and after treatment. The levels of PLT and FIB in the two groups of patients after treatment were significantly lower than before treatment, and the PLT levels in the observation group were lower than those in the control group.

Conclusion

The combination of Tripterygium glycosides and LMWH had good clinical effects in the treatment of children with HSPN, and it could improve the clinical symptoms, the mechanism of which might be related to the increase of PT, a decrease of PLT, and the improvement of coagulation function.

MicroRNA profiling in Chinese children with Henoch-Schonlein purpura and association between selected microRNAs and inflammatory biomarkers

AIM

This study aimed to profile the microRNA levels in Chinese Henoch-Schonlein purpura (HSP) children and to explore their association with inflammatory factors and T helper 17 (Th17)/regulatory T (Treg).

METHODS

Forty-five HSP children and 27 healthy controls were enrolled in this study, and microRNA levels were profiled with a microRNA microarray. The levels of selected microRNAs were determined by quantitative real-time PCR, and the levels of serum IgA, interleukin-6, interleukin-10 and interleukin-17A were detected by enzyme-linked immunosorbent assay. Additionally, Th17 and Treg cells were analysed by flow cytometry.

RESULTS

There were 9 up-regulated and 27 down-regulated microRNAs in the PBMCs of Chinese HSP children. Among them, miR-1-3p, miR-19b-1-5p and miR-29b-1-5p were up-regulated, while miR-483-5p and miR-1246 were down-regulated. Additionally, these selected microRNAs could differentiate HSP patients from healthy controls. Interestingly, miR-29b-1-5p was correlated with IgA, miR-19b-1-5p, miR-483-5p and miR-1246 were correlated with interleukin-6, while miR-1-3p and miR-1246 were correlated with Th17/Treg.

CONCLUSION

This study reveals that the altered microRNAs could differentiate HSP from the healthy, and were associated with inflammatory factors or Th17/Treg. It is indicated that alteration in these microRNAs may contribute to the HSP pathogenesis and may become therapeutic targets or diagnostic biomarkers for HSP.

Long non-coding RNA TUG1/microRNA-187-3p/TESC axis modulates progression of pituitary adenoma via regulating the NF-κB signaling pathway

The molecule mechanisms of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) in human diseases have been broadly studied recently, therefore, our research aimed to assess the effect of lncRNA taurine upregulated gene 1 (TUG1)/miR-187-3p/tescalcin (TESC) axis in pituitary adenoma (PA) by regulating the nuclear factor-kappa B (NF-κB) signaling pathway. We observed that TUG1 was upregulated in PA tissues and was associated with invasion, knosp grade and tumor size. TUG1 particularly bound to miR-187-3p. TUG1 knockdown inhibited cell proliferation, invasion, migration, and epithelial–mesenchymal transition, promoted apoptosis, and regulated the expression of NF-κB p65 and inhibitor of κB (IκB)-α in PA cells lines in vitro, and also inhibited tumor growth in vivo, and these effects were reversed by miR-187-3p reduction. Similarly, miR-187-3p elevation inhibited PA cell malignant behaviors and modulated the expression of NF-κB p65 and IκB-α in PA cells, and reduced in vivo tumor growth as well. TUG1 inhibition downregulated TESC, which was targeted by miR-187-3p. In conclusion, this study suggests that TUG1 sponges miR-187-3p to affect PA development by elevating TESC and regulating the NF-κB signaling pathway.