LncRNA NEAT1 accelerates renal mesangial cell injury via modulating the miR-146b/TRAF6/NF-κB axis in lupus nephritis.

Although growing advances have been made in the regulation of lupus nephritis recently, lupus nephritis is still one of the major causes of death in SLE patients and the pathogenesis remains largely unknown. Therefore, exploring the pathological mechanisms is urgently needed for designing and developing novel therapeutic strategies for lupus nephritis. Human renal mesangial cells (HRMCs) were transfected with sh-NEAT1, miR-146b mimic, pcDNA-NEAT1, miR-146b inhibitor, or sh-TRAF6 to modify their expression. Lipopolysaccharide (LPS) was used to induce inflammatory injury. Cell viability was examined with CCK8. Apoptosis was determined by flow cytometry and Hoechst staining. qRT-PCR and western blot were used to analyze gene expression. The secretion of inflammatory cytokines was examined with ELISA. The bindings of NEAT1 with miR-146b and miR-146b with TRAF6 were tested by dual-luciferase reporter assay. NEAT1 was upregulated in LPS-treated HRMCs. Both the knockdown of NEAT1 and TRAF6 suppressed the LPS-induced inflammatory injury in HRMCs. NEAT1 directly targeted miR-146b to control miR-146b-mediated regulation of TRAF6 expression in HRMCs. NEAT1 promoted the expression of TRAF6 via targeting miR-146b to accelerate the LPS-mediated renal mesangial cell injury in HRMCs. Moreover, TRAF6 activated the NF-κB signaling in HRMCs. NEAT1 accelerated renal mesangial cell injury via directly targeting miR-146b, promoting the expression of TRAF6, and activating the NF-κB signaling in lupus nephritis. Our investigation elucidated novel pathological mechanisms and provided potential therapeutic targets for lupus nephritis.

Therapeutic effects of mesenchymal stem cell-derived microvesicles on pulmonary arterial hypertension in rats.

AIM: Microvesicles (MVs) are nanoscale membrane fragments released from virtually all cell types upon activation or apoptosis, and may contribute to the beneficial effects of stem cell therapy. In this study, we investigated the therapeutic effects of mesenchymal stem cell (MSC) derived MVs (MSC-MVs) on pulmonary artery hypertension (PAH) in rats. METHODS: MSC-MVs were isolated from rat bone marrow MSCs that were cultured in a serum-free conditioned medium. Transmission electron microscopy (TEM), flow cytometry and nanoparticle tracking analysis (NTA) were used to characterize the MVs. Adult SD rats were injected with monocrotaline (50 mg/kg, sc) to induce PAH. Three weeks later, the rats were intravenously injected with MSCs, MSC-MVs or saline for 2 weeks. At the end of treatments, the hemodynamic parameters and pathological right ventricular and pulmonary arterial remodeling were analyzed in each group. RESULTS: The MSC-MVs showed general morphologic characteristics of MVs and expressed annexin V and CD29 markers under TEM, and their size ranged from 40 to 300 nm. Intravenous injection of MSC-MVs or MSCs significantly ameliorated the mean pulmonary artery pressure (mPAP) and mean right ventricle pressure (mRVP) in PAH rats. Furthermore, intravenous injection of MSC-MVs or MSCs significantly decreased the right ventricle (RV) hypertrophy and pulmonary arteriole area index (AI) and thickness index (TI) in PAH rats. CONCLUSION: Intravenous injection of MSC-MVs or MSCs produces similar beneficial effects for treating PAH, and our results provide a basis for cell-free approach in stem cell therapy.

Integrative Analysis of miRNA and circRNA Expression Profiles and Interaction Network in HSV-1-Infected Primary Corneal Epithelial Cells.

PURPOSE: Circular RNAs (circRNAs) are products of alternative splicing with roles as competitive endogenous RNAs or microRNA sponges, regulating gene expression and biological processes. However, the involvement of circRNAs in herpes simplex keratitis remains largely unexplored. METHODS: This study examines circRNA and miRNA expression profiles in primary human corneal epithelial cells infected with HSV-1, compared to uninfected controls, using microarray analysis. Bioinformatic analysis predicted the potential function of the dysregulated circRNAs and microRNA response elements (MREs) in these circRNAs, forming an interaction network between dysregulated circRNAs and miRNAs. RESULTS: A total of 332 circRNAs and 16 miRNAs were upregulated, while 80 circRNAs and six miRNAs were downregulated (fold change ≥2.0 and p < 0.05). Gene ontology (GO) and KEGG pathway analyses were performed on parental genes of dysregulated circRNAs to uncover potential functions in HSV-1 infection. Notably, miR-181b-5p, miR-338-3p, miR-635, and miR-222-3p emerged as pivotal miRNAs interacting with multiple dysregulated circRNAs. CONCLUSIONS: This comprehensive study offers insights into differentially expressed circRNAs and miRNAs during HSV-1 infection in corneal epithelial cells, shedding light on circRNA-miRNA interactions' potential role in herpes simplex keratitis pathogenesis.

Lactobacillus rhamnosus GG ameliorates hyperuricemia in a novel model.

Hyperuricemia (HUA) is a metabolic syndrome caused by abnormal purine metabolism. Although recent studies have noted a relationship between the gut microbiota and gout, whether the microbiota could ameliorate HUA-associated systemic purine metabolism remains unclear. In this study, we constructed a novel model of HUA in geese and investigated the mechanism by which Lactobacillus rhamnosus GG (LGG) could have beneficial effects on HUA. The administration of antibiotics and fecal microbiota transplantation (FMT) experiments were used in this HUA goose model. The effects of LGG and its metabolites on HUA were evaluated in vivo and in vitro. Heterogeneous expression and gene knockout of LGG revealed the mechanism of LGG. Multi-omics analysis revealed that the Lactobacillus genus is associated with changes in purine metabolism in HUA. This study showed that LGG and its metabolites could alleviate HUA through the gut-liver-kidney axis. Whole-genome analysis, heterogeneous expression, and gene knockout of LGG enzymes ABC-type multidrug transport system (ABCT), inosine-uridine nucleoside N-ribohydrolase (iunH), and xanthine permease (pbuX) demonstrated the function of nucleoside degradation in LGG. Multi-omics and a correlation analysis in HUA patients and this goose model revealed that a serum proline deficiency, as well as changes in Collinsella and Lactobacillus, may be associated with the occurrence of HUA. Our findings demonstrated the potential of a goose model of diet-induced HUA, and LGG and proline could be promising therapies for HUA.

Distributional responses to climate change of two maple species in southern China.

Climate change is a major factor affecting biodiversity and species distribution, particularly of montane species. Species may respond to climate change by shifting their range to higher elevations. The southeastern Qinghai-Tibetan Plateau (QTP) and the Hengduan Mountains are considered as global biodiversity hotspots. However, information on the response of maple species to climate change in these regions was limited. Therefore, we selected two maple species that occur there and assessed changes in their habitat suitability under past, present and future climate scenarios in Biomod2. The results showed that temperature seasonality (bio4) was the most critical factor influencing their potential distributions. The distribution of potentially suitable habitat for Acer caesium and Acer stachyophyllum was predicted to be larger during the LGM compared to the present. Under the current climate scenario, the largest areas of potentially suitable habitat for these species were mainly located in southeastern Tibet, the Hengduan Mountains in northwestern Yunnan and western Sichuan, the Qinling-Daba Mountains in southern Gansu and the Wumeng-Daliang Mountains in northeastern Yunnan, western Guizhou and southeastern Sichuan. Under future climate change scenarios, the predicted loss of suitable habitat areas for these two species ranged from 13.78% to 45.71% and the increase ranged from 18.88% to 57.98%, with an overall increasing trend. The suitable habitat areas were predicted to shift towards the eastern parts of the QTP under both the pessimistic and optimistic future climate change scenarios in the 2050s and the 2070s, which became evident as global warming intensified, particularly in the eastern QTP and the Hengduan Mountains. Our results highlight the possibility that the diverse topography along altitudinal gradients in the QTP and the Hengduan Mountains may potentially mitigate the range contraction of mountain plants in response to climate warming. These findings provide a basis for planning conservation areas, planting and species conservation in the mountainous areas of southern China under the anticipated global warming.

[Preliminary study on the efficacy and safety of oral sildenafil in pulmonary arterial hypertension in China].

OBJECTIVE: Sildenafil has been shown to be effective in pulmonary arterial hypertension (PAH). However, the impact of sildenafil on PAH has been under-investigated in China. The aim of the present study was to evaluate the efficacy and safety of oral sildenafil in PAH patients in China. METHODS: In this prospective, open-label and multi-center study, 90 patients were recruited from 14 centers to receive oral sildenafil (75 mg/d) for 12 weeks. They underwent a six-minute walk test (SMWT) and cardiac catheterization at the beginning and the end of 12 weeks. The primary endpoint was the changes in exercise capacity as assessed by SMWT. And the secondary endpoints included assessment of functional class, evaluation of cardiopulmonary hemodynamics and clinical deterioration (defined as death, transplantation and re-hospitalization for PAH). Drug safety and tolerability were also examined. RESULTS: There were 19 males and 71 females with an average age of 32.5 ± 12.1 years old (range: 18 - 61). Their etiologies were idiopathic (n = 15), related with congenital heart disease (n = 60), or related with connective tissue disease (n = 9) and chronic thromboembolic pulmonary hypertension (n = 6). Oral sildenafil significantly increased the SMWT distances [(342 ± 93) m vs. (403 ± 88) m, P < 0.001]. There was also remarkable improvement in Borg dyspnea score (2.9 ± 2.6 vs. 2.4 ± 2.0, P = 0.005). Furthermore, significant improvements in World Healthy Organization (WHO) functional class and cardiopulmonary hemodynamics were also found (mean pulmonary artery pressure, P < 0.001; cardiac index, P < 0.001; pulmonary vascular resistance, P < 0.001). Side effects were mild and consistent with other reports. CONCLUSION: This study confirms and extends previous studies. Oral sildenafil is both safe and effective for the treatment of adult PAH patients in China.

MiR-146b-5p targets IFI35 to inhibit inflammatory response and apoptosis via JAK1/STAT1 signalling in lipopolysaccharide-induced glomerular cells.

The dysregulated microRNAs (miRNAs) are implicated in the malignancy of lupus nephritis (LN). This work aims to analyse the effect and mechanism of miR-146b-5p in lipopolysaccharides (LPS)-induced model of LN in vitro. The serum samples of LN patients and normal volunteers were collected. HK-2 cells were challenged via LPS. miR-146b-5p and interferon-induced protein 35 (IFI35) abundances were detected via quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. The inflammatory response was assessed via inflammatory cytokines levels via qRT-PCR and enzyme-linked immunosorbent assay. Cell apoptosis was analysed via flow cytometry and apoptotic protein levels. The protein levels of JAK1/STAT1 signalling were detected via western blot. The relationship of miR-146b-5p and IFI35 was analysed via bioinformatics and dual-luciferase reporter assays. This study revealed that miR-146b-5p level was declined and IFI35 abundance was elevated in serum of LN patients and LPS-challenged HK-2 cells. Functionally, IFI35 overexpression promoted LPS-caused inflammatory response and cell apoptosis, and knockdown of IFI35 caused an opposite trend. Meanwhile, miR-146b-5p targeted IFI35 to suppress inflammatory response and cell inflammatory response and apoptosis via inactivating the JAK1/STAT1 pathway. MiR-146b-5p suppressed inflammatory response and cell apoptosis by IFI35 mediated-JAK1/STAT1 signalling in HK-2 cells, which provided a new mechanism for understanding the pathogenesis of LN.

Effect of Cross-Linked Hyaluronate Scaffold on Cartilage Repair: An In Vivo Study.

OBJECTIVE: To determine the safety and effectiveness of a cross-linked sodium hyaluronate (CHA) scaffold in cartilage repair. METHODS: Physicochemical properties of the scaffold were determined. The safety and effectiveness of the scaffold for cartilage repair were evaluated in a minipig model of a full-thickness cartilage defect with microfracture surgery. Postoperative observation and hematological examination were used to evaluate the safety of the CHA scaffold implantation. Pathological examination as well as biomechanical testing, including Young's modulus, stress relaxation time, and creep time, were conducted at 6 and 12 months postsurgery to assess the effectiveness of the scaffold for cartilage repair. Furthermore, type II collagen and glycosaminoglycan content were determined to confirm the influence of the scaffold in the damaged cartilage tissue. RESULTS: The results showed that the routine hematological indexes of the experimental animals were within the normal physiological ranges, which confirmed the safety of CHA scaffold implantation. Based on macroscopic observation, it was evident that repair of the defective cartilage in the animal knee joint began during the 6 months postoperation and was gradually enhanced from the central to the surrounding region. The repair smoothness and color of the 12-month cartilage samples from the operation area were better than those of the 6-month samples, and the results for the CHA scaffold implantation group were better than the control group. Greater cell degeneration and degeneration of the adjacent cartilage was found in the implantation group compared with the control group at both 6 and 12 months postoperation, evaluated by O'Driscoll Articular Cartilage Histology Scoring. Implantation with the CHA scaffold matrix promoted cartilage repair and improved its compression capacity. The type II collagen level in the CHA scaffold implantation group tended to be higher than that in the control group at 6 months (2.33 ± 1.50 vs 1.68 ± 0.56) and 12 months postsurgery (3.37 ± 1.70 vs 2.06 ± 0.63). The GAG content in the cartilage of the control group was significantly lower than that of the experimental group (2.17 ± 0.43 vs 3.64 ± 1.17, P = 0.002 at 6 months and 2.27 ± 0.38 vs 4.12 ± 1.02, P = 0.002 at 12 months). Type II collagen and glycosaminoglycan content also demonstrated that CHA was beneficial for the accumulation of both these vital substances in the cartilage tissue. CONCLUSIONS: The CHA scaffold displayed the ability to promote cartilage repair when applied in microfracture surgery, which makes it a promising material for application in the area of cartilage tissue engineering.

DBC2 gene is silenced by promoter methylation in bladder cancer.

Deletions at 8p are frequent in many human cancers and represent a genetic marker associated with a more aggressive tumor phenotype. Previous mutational analysis of DBC2 (deleted in breast cancer 2), a tumor suppressor gene located in the region of loss of heterozygosity (LOH) on 8p21, failed to show a high frequency of mutation linked to low expression in bladder cancer. Promoter hypermethylation may be an alternative mechanism of inactivation of the second allele. We detected the methylation status and expression of the DBC2 gene in 75 bladder cancer samples and 57 corresponding normal tissues. Aberrant methylation and down-regulation of DBC2 were observed preferentially in tumor samples (P < 0.05), and the expression changes were associated with methylation (P < 0.05). These findings, together with the previously mutation reports, suggest that aberrant methylation in DBC2 promoter may be responsible for the expression loss of DBC2 expression in bladder cancer and this hypermethylation event could play a crucial role in the early stage of bladder tumorigenesis.