Case report: Severe pneumonia and pneumomediastinum in a previously robust adolescent caused by Omicron BA.5.2.

The manifestation of severe pneumonia is only occasional, and pneumomediastinum is a condition that occurs rarely in Coronavirus disease 2019 (COVID-19) patients, especially in those patients who are infected with the Omicron variant. In addition, whether severe pneumonia or pneumomediastinum often occurs in patients in older age, in poor physical condition, or with underlying diseases remains to be ascertained. To date, severe pneumonia and pneumomediastinum due to Omicron infection had not been reported in a young patient with an excellent physical condition. In this study, we report such a case with the aforementioned manifestations in a robust adolescent infected with Omicron BA.5.2.

HMGB1 Inhibits HNF1A to Modulate Liver Fibrogenesis via p65/miR-146b Signaling.

High mobility group box 1 (HMGB1) is essential for the pathogenesis of liver injury and liver fibrosis. We previously revealed that miR-146b promotes hepatic stellate cells (HSCs) activation and proliferation. Nevertheless, the potential mechanisms are still unknown. Herein, HMGB1 increased HSCs proliferation and COL1A1 and α-SMA protein levels. However, the knockdown of miR-146b inhibited HSCs proliferation and COL1A1 and α-SMA protein levels induced via HMGB1 treatment. miR-146b was upregulated by HMGB1 and miR-146b targeted hepatocyte nuclear factor 1A (HNF1A) 3'-untranslated region (3'UTR) to modulate its expression negatively. Further, we confirmed that HMGB1 might elicit miR-146b expression via p65 within HSCs. Knockdown or block of HMGB1 relieved the CCl4-induced liver fibrosis. In fibrotic liver tissues, miR-146b expression was positively correlated with p65 mRNA, but HNF1A mRNA was inversely correlated with p65, and miR-146b expression. In summary, our findings suggest that HMGB1/p65/miR-146b/HNF1A signaling exerts a crucial effect on liver fibrogenesis via the regulation of HSC function.

MicroRNA-132-3p regulates cell proliferation, apoptosis, migration and invasion of liver cancer by targeting Sox4.

The present study investigated whether microRNA (miR)-132-3p targeted transcription factor SOX-4 (Sox4) for the inhibition of proliferation, migration, invasion and promotion of apoptosis in liver cancer (LC) cells. The expression of miR132-3p and Sox4 mRNA was evaluated by quantitative PCR and protein expression was determined by western blot analysis. Cell proliferation, apoptosis, migration, and invasion were assessed at different time points by the MTT assay, flow cytometry analysis, wound healing assay and Transwell migration assay, respectively. Bioinformatics prediction and luciferase assays were performed to validate and confirm Sox4as a potential target of miR-132p. There was a reduced expression of miR-132-3p in HepG2 and Huh7 cell lines compared with HccLM3 cells. Overexpression of miR-132-3p resulted in significant inhibition of proliferation and induction of apoptosis in LC cells. Moreover, migration and invasion of HepG2 cells were suppressed by over expressing miR-132-3p. However, downregulation of miR-132-3p in Hep-G2 cells promoted cell growth, invasion and migration and inhibited apoptosis. Bioinformatics analysis predicted Sox4 as a potential target of miR-132-3p, which was further confirmed by the luciferase reporter assay. In addition, an inverse association was observed between miR-132-3p and Sox4 expression. miR-132-3p may regulate the proliferation, apoptosis, migration and invasion of HepG2 cells by targeting Sox4.

High-Throughput Sequencing Strategy for miR-146b-regulated circRNA Expression in Hepatic Stellate Cells.

BACKGROUND This study was designed to detect and analyze miR-146b-mediated circular RNA (circRNA) expression in hepatic stellate cells. MATERIAL AND METHODS The experiment was divided into a control group and a siRNA-miR-146b group. The interference efficiency of siRNA-miR-146b was confirmed by real-time quantitative reverse transcription PCR (qRT-PCR) and the cells were collected, and total RNA was collected for high flux sequencing. The miRNA-targeted carcass were predicted. Finally, the expression of 5 circRNAs was verified by qRT-PCR. RESULTS miR-146b expression in the siRNA-miR-146b group was significantly lower than that in the control group. The quality of the original sequencing data and the processed data satisfied with the analysis, and the expression of circRNAs was modulated after the reduction of miR-146b. Among them, 18 circRNAs were upregulated, while 77 circRNAs were downregulated in the miR-146b group compared with the control group. The gene prediction showed that hsa_circ1887 was the largest contact point in miRNA and circRNA regulatory networks. qRT-PCR showed that rno-circRNA-469, rno-circRNA-1138, rno-circRNA-2168 and rno-circRAN-1907 were significantly reduced, while circRNA-1984 was significantly promoted in the siRNA-miR-146b group compared with the control group, which were consistent with the measurements by high-throughput sequencing technique. CONCLUSIONS miR-146b could regulate the expression of circRNAs in HSCs, which might take part in the formation and development of hepatic fibrosis.

The possible association between AQP9 in the intestinal epithelium and acute liver injury­induced intestinal epithelium damage.

The present study aimed to investigate the expression and function of aquaporin (AQP)9 in the intestinal tract of acute liver injury rat models. A total of 20 Sprague Dawley rats were randomly divided into four groups: Normal control (NC) group and acute liver injury groups (24, 48 and 72 h). Acute liver injury rat models were established using D­amino galactose, and the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (Tbil) and albumin were determined using an automatic biochemical analyzer. Proteins levels of myosin light chain kinase (MLCK) in rat intestinal mucosa were investigated via immunohistochemistry. Pathological features were observed using hematoxylin and eosin (H&E) staining. MLCK, AQP9 and claudin­1 protein expression levels were detected via western blotting. Levels of ALT and AST in acute liver injury rats were revealed to steadily increase between 24 and 48 h time intervals, reaching a peak level at 48 h. Furthermore, TBil levels increased significantly until 72 h. Levels of ALT were revealed to significantly increase until the 48 h time interval, and then steadily decreased until the 72 h time interval. The acute liver injury 72 h group exhibited the greatest levels of MLCK expression among the three acute liver injury groups; however, all three acute liver injury groups exhibited enhanced levels of MLCK expression compared with the NC group. Protein levels of AQP9 and claudin­1 were enhanced in the NC group compared with the three acute liver injury groups. H&E staining demonstrated that terminal ileum mucosal layer tissues obtained from the acute liver injury rats exhibited visible neutrophil infiltration. Furthermore, the results revealed that levels of tumor necrosis factor­α, interleukin (IL)­6 and IL­10 serum cytokines were significantly increased in the acute liver injury groups. In addition, AQP9 protein expression was suppressed in acute liver injury rats, which induced pathological alterations in terminal ileum tissues may be associated with changes of claudin­1 and MLCK protein levels.

Oxidored-nitro domain-containing protein 1 promotes liver fibrosis by activating the Wnt/ß-catenin signaling pathway in vitro.

Hepatic fibrosis is a characteristic of various types of chronic liver diseases, and may further develop into liver cirrhosis and liver cancer. Oxidored­nitro domain­containing protein 1 (NOR1) expression levels are greater in hepatitis, cirrhosis and hepatocellular carcinoma samples compared with from normal liver samples. However, the importance of NOR1 in liver fibrosis remains to be elucidated. The present study aimed to investigate the effect of NOR1 on the proliferation and matrix expression of human hepatic stellate cells (HSCs) in vitro. Additionally, the molecular mechanisms underlying the role of NOR1 in the activation of HSCs was investigated. The present study determined that transforming growth factor ß1 (TGF­ß1) may induce NOR1 expression in HSCs in a dose­dependent manner, as determined by reverse transcription­quantitative polymerase chain reaction and western blot analysis. NOR1­small hairpin (sh)RNA was transfected into TGF­ß1­treated HSCs to knock down NOR1. The MTT assay revealed that TGF­ß1­induced cell proliferation was significantly inhibited in the NOR1­shRNA group. In addition, NOR1 knockdown significantly inhibited TGF­ß1­induced protein expression of fibrosis indexes, including collagen 1, 3 and α­smooth muscle actin (α­SMA). Subsequently, NOR1­pcDNA3.1 was transfected into HSCs to overexpress NOR1. It was revealed that NOR1 overexpression may activate the Wnt/ß­catenin pathway in HSCs. The gain­of function experiments demonstrated that NOR1 overexpression promoted cell proliferation and the expression of fibrosis indexes; however, these effects may be attenuated by dickkopf­1, an inhibitor of the Wnt/ß­catenin signaling pathway. In conclusion, the present study demonstrated that NOR1 activates HSCs and contributes to liver fibrosis in vitro and this effect was achieved through the activation of the Wnt/ß­catenin pathway. Therefore, the current study may provide a novel target for the treatment of chronic liver diseases.

Role of growth factor receptor-bound 2 in CCl4-induced hepatic fibrosis.

BACKGROUND: Growth Factor Receptor-bound 2 (GRB2) plays a crucial role in regulation of cellular function including proliferation and differentiation, and we previously identified GRB2 as promoting HSCs (HSCs) proliferation. However, the underlying mechanisms that are involving in the regulation of GRB2 in hepatic fibrogenesis remain unknown. METHODS: In the present study, we tested the function of GRB2 in hepatic fibrosis. Hepatic fibrosis was induced by subcutaneous CCl4 administration at a dose of 3mL/kg in rats. The rat HSC cell line HSC-T6 were cultured for proliferation investigation by CCK-8 and BrdU incorporation method. The levels of GRB2, HMGB1, PI3K/AKT, COL1A1 and α-SMA were analyzed by western blot or real-time PCR. RESULTS: showed that the expression of GRB2 and HMGB1 was obviously increased in liver tissues of hepatic fibrosis rats accompanied by up-regulation of COL1A1 and α-SMA. In cultured HSCs, application of exogenous HMGB1 induced cell proliferation and cell proliferation rate concomitantly with up-regulation of GRB2 expression and PI3K/AKT phosphorylation. The effects of HMGB1-induced proliferation of HSCs and up-regulation of COL1A1 and α-SMA were abolished by GRB2 siRNA. HMGB1-induced proliferation of HSCs and up-regulation of COL1A1 and α-SMA was reversed in the presence of LY294002, an inhibitor of PI3K inhibitor. CONCLUSIONS: These findings suggest that GRB2 plays an important role in CCl4-induced hepatic fibrosis by regulating HSCs' function, and up-regulation of GRB2 induced by HMGB1 is mediated via the PI3K/AKT pathway.

MicroRNA-146b regulates hepatic stellate cell activation via targeting of KLF4.

 Background. We previously identified miR-146b as being up-regulated during the development of hepatic fibrosis using deep sequencing technology and gene expression analysis. However, the roles and related mechanisms of miR-146b in hepatic stellate cells (HSCs), which are involved in fibrogenesis and fibrosis, have not been elucidated. RESULTS: We report that miR-146b expression was increased in TGF-ß1-treated HSCs. TGF- ß1 enhanced α-SMA and COL1A1 protein expression in HSCs and stimulated proliferation of these cells compared with cells transfected with inhibitor NC. Conversely, miR-146b knock-down decreased α-SMA and COL1A1 expression and inhibited HSC proliferation. In addition, we found that miR-146b specifically regulated the translation of Krüppel-like factor 4 (KLF4) by targeting its 3' untranslated region. Forced expression of KLF4 inhibited TGF- ß1-induced enhancement of α-SMA and COL1A1 expression in HSCs, as well as proliferation of these cells. Moreover, miR-146b expression was negatively associated with KLF4 expression but positively associated with expression of α-SMA and COL1A1 during hepatic fibrosis. CONCLUSIONS: Our findings demonstrate the participation of miR-146b as a novel upstream effector of HSC activation via direct targeting of KLF4. Thus, targeted transfer of miR-146b into HSCs could be a useful strategy for the treatment of hepatic fibrosis.

MicroRNA-19b reduces hepatic stellate cell proliferation by targeting GRB2 in hepatic fibrosis models in vivo and in vitro as part of the inhibitory effect of estradiol.

Estradiol (E2) is a major determinant of gender-based differences in the development of hepatic fibrosis. MicroRNAs (miRNAs) are endogenous 19-25 nucleotide, noncoding, single-stranded RNAs that regulate gene expression by blocking the translation or decreasing the stability of mRNAs and play an important role in liver fibrosis. The mechanisms underlying the regulation of miRNAs by E2 remain largely unknown. In this study, miR-19b levels were higher and were associated with lower GRB2 mRNA and protein levels in female rats more than in male rats. We also showed that miR-19b levels were down-regulated, were associated with the up-regulation of GRB2 mRNA and protein levels in PS (porcine serum-induced hepatic fibrosis) versus NS (normal control) groups and were up-regulated when associated with the down-regulation of GRB2 mRNA and protein levels in PS + E2 versus PS and in aHSC + E2 (estradiol treated aHSC) versus aHSC groups. MiR-19b expression inhibited cell proliferation in aHSCs, and also down-regulated GRB2 protein expression. The overexpression of miR-19b inhibited cell growth and suppressed COL1A1 protein levels by decreasing the levels of GRB2. However, the forced expression of GRB2 partly rescued the effect of miR-19b in the cells, attenuated cell proliferation, and suppressed the GRB2 protein level by up-regulating the levels of GRB2. Taken together, these findings will shed light on the role of miR-19b in regulating aHSC proliferation via the miR-19b/GRB2 axis. This newly identified miR-19b/GRB2 interaction provided novel insights into the suppressive effect of E2 on HSC proliferation and might facilitate the development of therapies targeting hepatic fibrosis.

Deep sequencing analysis of microRNA expression in porcine serum-induced hepatic fibrosis rats.

AIM: Recent studies have suggested miRNA dysregulation in liver tissue mediates the pathogenesis of various liver diseases especially liver fibrosis, but the microRNA changes during PS-induced hepatic fibrosis are still unknown. The purpose of this study was to screen the miRNA differences in rat liver fibrosis model and clarify the relationship of miRNAs with the development of PS-induced liver fibrosis. MATERIAL AND METHODS: Two fibrotic and two normal liver tissues from 20 Sprague-Dawley rats were collected and sequenced. MiRNA profiling results and fibrosis-related genes were validated by quantitative real-time polymerase chain reaction (qRT-PCR) and bioinformatics was used to predict miRNA targets. RESULTS: In total, 48 miRNAs were detected to be aberrantly expressed in fibrosis tissue compared to normal tissue. Further functional analysis of the deregulated miRNA targets revealed the miRNAs are involved in several biological functions and pathways. In addition, the expression level of miR-27a and miR-146b and fibrosis-related genes were significantly up-regulated by using qRT-PCR in fibrotic liver tissues when compared to the normal liver tissues. CONCLUSION: PS-induced hepatic fibrosis results in up-regulation of the miR-27a and miR-146b in liver tissues, suggestingmiR-27a and miR-146b would be associated with the development of PS-induced liver fibrosis and be potential therapeutic targets during hepatic fibrosis.