Protective Role of TNIP2 in Myocardial Injury Induced by Acute Pancreatitis and Its Mechanism

Icariside II Alleviates Chondrocyte Inflammatory Injury by Inhibiting the TNIP2/NF-κB Pathway

Icariside II exerts protective effects against various diseases; however, its specific effects on osteoarthritis (OA) remain unclear. Therefore, in this study, we aimed to investigate the effects of icariside II in an in vitro model of OA and analyze its action mechanisms. We established an in vitro OA model by treating a human chondrocyte cell line (CHON-001) with interleukin (IL)-1β, followed by treatment with different concentrations of icariside II. Cell viability was measured using the methyl thiazolyl tetrazolium assay, and the level of lactate dehydrogenase (LDH) released from cells was determined using the appropriate kit. Tumor necrosis factor (TNF)-α, IL-6, and IL-8 levels were determined via enzyme-linked immunosorbent assay. Flow cytometry was used to assess apoptosis. Apoptosisrelated protein expression levels and TNFAIP3-interacting protein 2 (TNIP2)/nuclear factor (NF)-κB signaling pathway were analyzed via reverse transcription-quantitative polymerase chain reaction and western blotting. Furthermore, TNIP2-small interfering RNA (siRNA) was used to determine whether the TNIP2/NF-κB pathway influences the effects of icariside II on OA. Results indicated that Icariside II did not exert any significant toxic effects on CHON-001 cells. It inhibited IL-1β-induced apoptosis and increase in LDH levels and enhanced the inflammatory response. Additionally, icariside II reversed the IL-1β-induced decrease in TNIP2 levels and increase in NF-κB phosphorylation. TNIP2-siRNA revealed that the TNIP2/NF-κB signaling pathway influenced the alleviating effects of icariside II on OA. In conclusion, our results revealed that icariside II attenuated IL-1β-induced inflammatory injury in chondrocytes by increasing TNIP2 expression and inhibiting NF-κB pathway activation, highlighting its therapeutic potential for OA.

TNFAIP3 interacting protein 2 relieves lipopolysaccharide (LPS)-induced inflammatory injury in endometritis by inhibiting NF-kappaB activation

BACKGROUND

Endometritis seriously affects the health of women, and it is important to identify new targets for its treatment.

OBJECTIVE

This study aimed to explore the role of TNFAIP3 interacting protein 2 (TNIP2) in endometritis through human endometrial epithelial cells (hEECs) stimulated by lipopolysaccharide (LPS).

METHODS

hEECs were induced with LPS to build a cellular model of endometritis. Cell growth and apoptosis were detected by cell counting kit-8 and flow cytometry. The TNIP2 mRNA and protein levels were measured using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis, respectively. The caspase3 activity was calculated using a Caspase3 activity kit. Interleukin (IL)-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) levels were determined by enzyme-linked-immunosorbent-assay. The reactive oxygen species (ROS), lactate dehydrogenase (LDH), catalase (CAT), and superoxide dismutase (SOD) levels were determined using the corresponding kits. Nuclear factor-kappaB (NF-κB) pathway was determined by western blot assay.

RESULTS

TNIP2 was downregulated in the LPS-induced endometritis cell model. Cell viability was reduced, apoptosis was enhanced, and IL-6, IL-1β, and TNF-α levels increased in LPS-induced hEECs. Additionally, LDH activity and ROS concentration were upregulated, whereas CAT and SOD activities were downregulated in LPS-induced hEECs. These results were reversed by TNIP2 overexpression. Moreover, the results hinted that NF-κB was involved in the effects of TNIP2 on the LPS-induced endometritis cell model.

CONCLUSION

TNIP2 alleviated endometritis by inhibiting the NF-κB pathway, suggesting a potential therapeutic target for endometritis.

Protective effect of TNIP2 on the inflammatory response of microglia after spinal cord injury in rats

BACKGROUND

Spinal cord injury (SCI) is a devastating disease that can lead to tissue loss and neurological dysfunction. TNIP2 is a negative regulator of NF-κB signaling due to its capacity to bind A20 and suppress inflammatory cytokines-induced NF-κB activation. However, the anti-inflammatory role of TNIP2 in SCI remains unclear. Our study's intention was to evaluate the effect of TNIP2 on the inflammatory response of microglia after spinal cord injury in rats.

METHODS

HE staining and Nissl staining were performed on day 3 following SCI to analyze the histological changes. To further investigate the functional changes of TNIP2 after SCI, we performed immunofluorescence staining experiments. The effect of LPS on TNIP2 expression in BV2 cells was examined by western blot. The levels of TNF-α, IL-1β, and IL-6 in spinal cord tissues of rats with SCI and in BV2 cells with LPS were measured by using qPCR.

RESULTS

TNIP2 expression was closely associated with the pathophysiology of SCI in rats, and TNIP2 was involved in regulating functional changes in microglia. TNIP2 expression was increased during SCI in rats and that overexpression of TNIP2 inhibited M1 polarization and pro-inflammatory cytokine production in microglia, which might ultimately protect against inflammatory responses through the MAPK and NF-κB signaling pathways.

CONCLUSIONS

The present study provides evidence for a role of TNIP2 in the regulation of inflammation in SCI and suggests that induction of TNIP2 expression alleviated the inflammatory response of microglia.

Aberrant Histone Modification of TNFAIP3, TLR4, TNIP2, miR-146a, and miR-155 in Major Depressive Disorder

Activated toll-like receptor (TLR) signaling has been well investigated in major depressive disorder (MDD). We previously reported that TNFAIP3, TLR4, TNIP2, miR-146a, and miR-155 play important roles in regulating the toll-like receptor 4 (TLR4) signaling pathway and may serve as novel targets in the pathogenesis of MDD. Recently, aberrant histone modification has been implicated in several psychiatric disorders, including schizophrenia and mood disorder; the most thoroughly studied modification is histone 3 lysine 4 tri-methylation (H3K4me3). In this work, we aimed to explore H3K4me3 differences in the promotors of genes encoding the abovementioned factors in patients with MDD, and whether they were altered after antidepressant treatment. A total of 30 MDD patients and 28 healthy controls were recruited. Peripheral blood mononuclear cells (PBMCs) were collected. The levels of H3K4me3 in the promoters of TNFAIP3, TLR4, TNIP2, miR-146a, and miR-155 were measured through chromatin immunoprecipitation (ChIP) followed by DNA methylation assay. Analysis of covariance was used to evaluate between-group differences after adjusting for age, sex, BMI, and smoking. In comparison with healthy controls, patients with MDD showed significantly lower H3K4me3 levels in the promoters of TNFAIP3, TLR4, TNIP2, miR-146a, and miR-155 in PBMCs. These levels were not significantly altered after completion of a 4-week antidepressant treatment. To explore the association between depression severity and H3K4me3 levels, a multiple linear regression model was generated. The results revealed that levels of H3K4me3 in the TNIP2 promoters a negative correlation with the 17-item Hamilton Depression Rating Scale (HAND-17) score, whereas that of TLR4 had a positive correlation with this score. The present results suggest that decreased H3K4me3 levels in the promoters of the genes encoding TNFAIP3, TLR4, miR-146a, miR-155, and TNIP2 are involved in psychopathology of major depressive disorder.

Ibuprofen Alleviates Acute Pancreatitis- (AP-) Induced Myocardial Injury by Inhibiting AIM2

Objective

The lack of certain trace elements such as selenium, molybdenum, magnesium or related nutrients in the soil, water quality and food in the disease area, which caused disturbance of myocardium metabolism and resulted in injury and necrosis. The aim of the study was to explore the mechanism of ibuprofen alleviating myocardial injury caused by acute pancreatitis (AP).

Method

We have established AP cell model and rat model. HE staining is used for histological examination. ELISA is used to determine the levels of proinflammatory cytokines (TNF-α and IL-6) and markers of myocardial injury (LDH and CK-MB). qRT-PCR and Western blot are used to analyze the mRNA and protein levels of related genes.

Results

The expression level of AIM2 was significantly increased in AP cells; downregulation of AIM2 alleviated inflammation and myocardial injury induced by AP cells; ibuprofen could inhibit the expression of AIM2 and alleviate inflammation and myocardial injury induced by AP cells. In vivo experiments have found that ibuprofen can inhibit the expression of AIM2 to alleviate myocardial injury in AP rat.

Conclusion

Ibuprofen can alleviate myocardial injury caused by acute pancreatitis by inhibiting the expression of AIM2.

miR-29a-3p transferred by mesenchymal stem cells-derived extracellular vesicles protects against myocardial injury after severe acute pancreatitis

AIMS

Acute pancreatitis (AP) is an inflammatory disease of the pancreas that may affect local tissues or remote organ systems, while severe acute pancreatitis (SAP) is a life-threatening disorder associated with multiple organ failure. In this investigation, we set about to determine whether microRNA-29a-3p (miR-29a-3p) carried by mesenchymal stem cell (MSCs)-derived extracellular vesicles (EVs) affects the myocardial injury during SAP.

MAIN METHODS

EVs were isolated from MSCs of rat bone marrow by differential centrifugation. An SAP rat model was developed and treated with MSCs-EVs and/or alteration of miR-29a-3p and HMGB1 expression, followed by assessment of the rats' cardiac function and inflammation. Next, cardiomyocytes H9C2 were co-cultured with MSC-EVs and internalization of EVs was evaluated, followed by evaluation of whether EVs could transmit miR-29a-3p cargos into H9C2 cells and affect their biological functions.

KEY FINDINGS

EVs derived from MSCs were observed to protect against SAP-induced myocardial injury. In SAP-induced rats, miR-29a-3p was under-expressed in myocardial tissues. In addition, we also confirmed that miR-29a-3p could be transferred into the H9C2 cardiomyocytes by MSC-derived EVs, which downregulated the expression of inflammatory markers and improve cardiac function to attenuate myocardial injury. Furthermore, miR-29a-3p inhibited the expression of HMGB1 to downregulate TLR4 expression and further inactivate the Akt signaling pathway.

SIGNIFICANCE

These findings support the cardioprotective action of miR-29a-3p transmitted by MSCs-derived EVs in SAP-induced myocardial injury via downregulation of the HMGB1/TLR4/Akt axis, highlighting a promising target for the EV-based therapy for SAP.

Pitfalls in AR42J-model of cerulein-induced acute pancreatitis

Background

AR42J are immortalized pancreatic adenocarcinoma cells that share similarities with pancreatic acinar cells. AR42J are often used as a cell-culture model of cerulein (CN)-induced acute pancreatitis (AP). Nevertheless, it is controversial how to treat AR42J for reliable induction of AP-like processes. Gene knockout and/or overexpression often remain challenging, as well. In this study, we demonstrate conditions for a reliable induction of proinflammatory markers upon CN treatment in AR42J and high transfection efficacy using Glyoxalase-I (Glo-I) as a target of interest.

Methods

Effects of dexamethasone (dexa) and CN on cell morphology and amylase secretion were analyzed via ELISA of supernatant. IL-6, TNF-α and NF-κB-p65 were measured via qRT-PCR, ELISA and Western Blot (WB). Transfection efficacy was determined by WB, qRT-PCR and immune fluorescence of pEGFP-N1-Glo-I-Vector and Glo-I-siRNA.

Results

Treatment of AR42J with 100 nm dexa is mandatory for differentiation to an acinar-cell-like phenotype and amylase production. CN resulted in secretion of amylase but did not influence amylase production. High levels of CN-induced amylase secretion were detected between 3 and 24 hours of incubation. Treatment with LPS alone or in combination with CN did not influence amylase release compared to control or CN. CN treatment resulted in increased TNF-α production but not secretion and did not influence IL-6 mRNA. CN-induced stimulation of NF-κB was found to be highest on protein levels after 6h of incubation. Transient transfection was able to induce overexpression on protein and mRNA levels, with highest effect after 12 to 24 hours. Gene-knockdown was achieved by using 30 pmol of siRNA leading to effective reduction of protein levels after 72 hours. CN did not induce amylase secretion in AR42J cell passages beyond 35.

Conclusion

AR42J cells demonstrate a reliable in-vitro model of CN-induced AP but specific conditions are mandatory to obtain reproducible data.

Neuroprotective Function of TNFAIP3 Interacting Protein 2 Against Oxygen and Glucose Deprivation/Reoxygenation-Induced Injury in Hippocampal Neuronal HT22 Cells Through Regulation of the TLR4/MyD88/NF-κB Pathway

BACKGROUND

Tumor necrosis factor-α (TNF-α)-induced protein 3-interacting protein 2 (TNIP2) has been well demonstrated to act as a principal contributor to the development of inflammatory diseases; however, the role of TNIP2 in cerebral ischemic/reperfusion injury has never been studied.

METHODS

Gene expression was examined by using quantitative real-time polymerase chain reaction and Western blot. The functional role of TNIP2 in oxygen and glucose deprivation/reoxygenation (OGD/R)-induced neuronal injury was evaluated using cell counting kit-8, terminal deoxynucleotidyl transferase dutp nick end labeling assay and enzyme-linked immunosorbent assay. Commercial kits were applied to evaluate the activity of NF-kappa-B (NF-κB) and caspase-3, as well as the release of lactate dehydrogenase release (LDH).

RESULTS

TNIP2 expression was substantially declined in HT22 cells following OGD/R stimulation. TNIP2 overexpression attenuated ODG/R-induced inflammation in HT22 cells, as evidenced by reduced levels of TNF-α, interleukin (IL)-1β, and intercellular cell adhesion molecule-1 (ICAM-1), and increased levels of IL-10. TNIP2 overexpression also reduced activity of NF-κB under ODG/R condition. Meanwhile, OGD/R treatment caused a reduction of cell viability and an elevation of cell apoptosis in HT22 cells, as indicated by the increase in LDH and caspase-3 activity. Whereas, OGD/R-induced HT22 cell injury was mitigated by TNIP2 overexpression in HT22 cells. Besides, we found the involvement of toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/NF-κB pathway in the neuroprotective effect of TNIP2 on OGD/R-induced HT22 cell damage.

CONCLUSION

TNIP2 overexpression mitigates OGD/R-induced inflammatory response and apoptosis. Moreover, TLR4/MyD88/NF-κB pathway participates in the protective effect of TNIP2 on OGD/R-induced neuronal damage.

Role of microRNA-15a-5p/TNFAIP3-interacting protein 2 axis in acute lung injury induced by traumatic hemorrhagic shock

The present study aimed to investigate the role of microRNA (miR)-15a-5p in the pathogenesis of acute lung injury induced by traumatic hemorrhagic shock (THS), and to explore the underlying molecular mechanism. The expression level of miR-15a-5p was detected using reverse transcription-quantitative (RT-qPCR) and the association between miR-15a-5p and TNFAIP3-interacting protein 2 (TNIP2) was revealed using TargetScan and dual luciferase reporter assays. To investigate the effect of miR-15a-5p on THS-induced acute lung injury, a THS rat model was established. Lung capillary permeability and lung edema were then determined. Moreover, proinflammatory factors in the bronchoalveolar lavage fluid (BALF) and serum of the THS rat model were detected using ELISA. In addition, protein levels in the current study were measured via western blotting. It was revealed that miR-15a-5p was significantly upregulated in both patients with THS and samples from the THS rat model. TNIP2 represents a direct target of miR-15a-5p, and it was downregulated in both patients with THS and the THS rat model. Further analyses indicated that downregulation of miR-15a-5p significantly relieved acute lung injury induced by THS, evidenced by a decreased ratio of Evan's blue dye (EBD) in the BALF to EBD in plasma of THS rats, decreased lung permeability index and reduced lung wet/dry ratio. Inhibition of miR-15a-5p also decreased THS-induced upregulation of pro-inflammatory factors. Furthermore, the data revealed that THS-induced NF-κB activation in the lung tissues of rats was inhibited by miR-15a-5p knockdown. Moreover, it was demonstrated that all the effects of miR-15a-5p on THS rats were ablated following TNIP2 silencing. Taken together, the data of the current study indicate that miR-15a-5p downregulation serves a protective role in THS-induced acute lung injury via directly targeting TNIP2.

Protective effect of diallyl disulfide against cerulein-induced acute pancreatitis and associated lung injury in mice

Garlic (Allium sativum) - derived organosulfur compound diallyl disulfide (DADS) possesses antioxidant, anti-inflammatory and anti-cancer effects. This study was aimed to investigate the anti-inflammatory role and the underlying molecular mechanisms of DADS in cerulein-induced acute pancreatitis (AP) and associated lung injury. Administration of DADS significantly attenuated the severity of pancreatic and pulmonary inflammation by inhibiting cerulein induced serum amylase, myeloperoxidase activity (MPO) and histological changes in pancreas and lung. Furthermore, the anti-inflammatory effect of DADS was associated with the decrease in tumor necrosis factor (TNF)-α,cystathionine-γ-lyase (CSE), preprotachykinin A (PPTA), neurokinin-1-receptor (NK1R) expression and hydrogen sulfide (H₂S) production in both pancreas and lung. In addition, DADS reduced caerulein-induced I-κB degradation and subsequent translocation of NF-κB in the pancreas and lung. These results show for the first time that in AP, DADS exhibits an anti-inflammatory effect by inhibiting CSE/H₂S and SP/NK1R signaling and NF-кB pathway.

Combinatory antibiotic treatment protects against experimental acute pancreatitis by suppressing gut bacterial translocation to pancreas and inhibiting NLRP3 inflammasome pathway

Gut bacterial translocation following impaired gut barrier is a critical determinant of initiating and aggravating acute pancreatitis (AP). Antibiotic combination (ABX; vancomycin, neomycin and polymyxin b) is capable of reducing gut bacteria, but its efficacy in AP prevention and the underlying mechanism have not been investigated yet. AP was induced in BALB/c mice by caerulein (CAE) hyperstimulation. We found that ABX supplementation attenuated the severity of AP as evidenced by reduced pancreatic oedema and myeloperoxidase activity. The protective effect was also confirmed by improved histological morphology of the pancreas and decreased pro-inflammatory markers (IL-1β, TNF-α, MCP-1) in pancreas. ABX administration inhibits the activation of colonic TLR4/NLRP3 inflammasome pathway. Subsequently, down-regulated NLRP3 resulted in decreased colonic pro-inflammation (IL-1β, IL-6, MCP-1) and enhanced gut physical barrier as evidenced by up-regulation of tight junction proteins including occludin, claudin-1 and ZO-1, as well as improved histological morphology of the colon. Together, combinatory ABX therapy inhibited the translocation of gut bacteria to pancreas and its amplification effects on pancreatic inflammation by inhibiting the pancreatic NLRP3 pathway, and inhibiting intestinal-pancreatic inflammatory responses. The current study provides the basis for potential clinical application of ABX in AP.

Expression and role of TNIP2 in multiple organ dysfunction syndrome following severe trauma

Severe trauma can result in secondary multiple organ dysfunction syndrome (MODS) and death. Inflammation response and oxidative stress promote the occurrence and development of MODS. TNFAIP3‑interacting protein 2 (TNIP2), which can repress the activation of nuclear factor‑κB (NF‑κB) and may be involved in MODS progression, has not been studied in regards to MODS. The present study aimed to investigate the expression, role and mechanism of TNIP2 in MODS following severe trauma. The expression level of TNIP2 was initially detected in the blood of patients with MODS using reverse transcription‑quantitative polymerase chain reaction and western blot assay. Then, to investigate the role of TNIP2 in MODS, a MODS rat model was conducted by trauma and the model rats were treated with TNIP2‑plasmid (intraperitoneal injection). Blood levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), blood urea nitrogen (BUN), creatine (Cr) and creatine kinase (CK); and tumor necrosis factor α (TNF‑α), high‑mobility group box 1 (HMGB‑1), malondialdehyde (MDA) and total antioxidant capacity (TAC) in the different groups were assessed. In addition, activation of NF‑κB was assessed by detecting the level of phospho‑p65. The results showed that TNIP2 was significantly decreased in the blood of patients with MODS. TNIP2 was also significantly downregulated in the blood and the pulmonary, renal and hepatic tissues of MODS rats. The levels of ALT, AST, LDH, BUN, Cr and CK were markedly increased in the blood of MODS rats, and these increases were inhibited by TNIP2‑plasmid administration. Moreover, blood levels of TNF‑α, HMGB‑1 and MDA were significantly increased in MODS rats, while TAC was notably decreased, and these changes were prevented by TNIP2‑plasmid administration. Furthermore, it was found that activation of NF‑κB induced by MODS was eliminated by TNIP2‑plasmid. In conclusion, the data indicated that TNIP2 is significantly decreased in MODS following severe trauma, and it plays a protective role in MODS development by inhibiting the inflammation response and oxidative stress by preventing NF‑κB activation.