GSK-3β activation index is a potential indicator for recurrent inflammation of chronic rhinosinusitis without nasal polyps

A novel GSK3β inhibitor 5n attenuates acute kidney injury

Acute kidney injury (AKI) is a clinical syndrome with high morbidity and mortality caused by various factor. The specific strategies for AKI are still lacking. GSK3β is widely expressed in the kidneys. In acute models of injury, GSK3β promotes the systemic inflammatory response, increases the proinflammatory release of cytokines, induces apoptosis, and alters cell proliferation. We screened a series of 3-(4-pyridyl)-5-(4-sulfamido-phenyl)-1,2,4-oxadiazole derivatives which are recognized as new GSK3β inhibitors, and found that 5n had the least toxicity and the best cell protection. We then tested the anti-inflammatory and reno-protective effect of 5n in cisplatin-treated tubular epithelial cells. 5n had anti-inflammation effect indicated by phosphor-NF-κB detection. Finally, we found that 5n ameliorated renal injury and inflammation in cisplatin-induced AKI mouse model. Silencing GSK3β inhibited cell injury and inflammation induced by cisplatin. We found that GSK3β interacted with PP2Ac to modulate the activity of NF-κB. In conclusion, 5n, the novel GSK3β inhibitor, protects against AKI via PP2Ac-dependent mechanisms which may provide a potential strategy for the treatment of AKI in clinic.

Extracellular vesicles derived from mouse adipose-derived mesenchymal stem cells promote diabetic corneal epithelial wound healing through NGF/TrkA pathway activation involving dendritic cells

Diabetic keratopathy (DK) is a common ocular complication of diabetes in which the dendritic cells (DCs)-mediated inflammatory response plays an important role. Nerve growth factor (NGF)/Tropomyosin receptor kinase A (TrkA)-mediated inhibition of the nuclear factor kappa B (NF-κB) pathway can reduce inflammatory cytokine production. Extracellular vesicles (EVs) derived from mouse adipose-derived mesenchymal stem cells (mADSC-EVs) have been explored extensively as treatments for degenerative eye disease. However, mADSC-EVs is poorly studied in the DK models. In this study, we investigated the anti-inflammatory effects of mADSC-EVs and explored the underlying mechanisms in vitro and in vivo DK models. Our results showed that mADSC-EVs have significant therapeutic effects including increasing tear volume and the ratio of lacrimal gland/body weight, promoting corneal nerve regeneration, and sensation recovery in streptozotocin (STZ)-induced DK mice. In addition, mADSC-EVs significantly reduced the inflammatory response involving DCs, consistently up-regulated protein expression of the NGF/TrkA pathway, and importantly, reduced lipopolysaccharide (LPS)-mediated IL-6 and TNF-α expression and directly dependent on TrkA in the induced culture of bone marrow-derived DCs (BMDCs). Taken together, our findings revealed that mADSC-EVs promoted diabetic corneal epithelial wound healing through NGF/TrkA pathway activation involving DCs. Given the significant therapeutic efficacy of mADSC-EVs and its clinical application, mADSC-EVs appears to be a promising new therapy for DK.

MiR-155/GSK-3β mediates anti-inflammatory effect of Chikusetsusaponin IVa by inhibiting NF-κB signaling pathway in LPS-induced RAW264.7 cell

It has been demonstrated that Chikusetsusaponin IVa (CsIVa) possesses abundant biological activities. Herein, using LPS to establish acute inflammation model of mouse liver and cell line inflammation model, we investigated whether miR-155/GSK-3β regulated NF-κB signaling pathway, and CsIVa exerted anti-inflammatory effects by regulating miR-155/GSK-3β signaling pathway. Our results showed that LPS induced high expression of miR-155 and miR-155 promoted macrophage activation through GSK-3β. In addition, CsIVa inhibited inflammatory responses in LPS-induced mouse liver and RAW264.7 cells. Furthermore, we demonstrated that CsIVa improved the inflammatory response in LPS-induced RAW264.7 cells by inhibiting miR-155, increasing GSK-3β expression, and inhibiting NF-κB signaling pathway. In conclusion, our study reveals that CsIVa suppresses LPS-triggered immune response by miR-155/GSK-3β-NF-κB signaling pathway.

GSK3: A Kinase Balancing Promotion and Resolution of Inflammation

GSK3 has been implicated for years in the regulation of inflammation and addressed in a plethora of scientific reports using a variety of experimental (disease) models and approaches. However, the specific role of GSK3 in the inflammatory process is still not fully understood and controversially discussed. Following a detailed overview of structure, function, and various regulatory levels, this review focusses on the immunoregulatory functions of GSK3, including the current knowledge obtained from animal models. Its impact on pro-inflammatory cytokine/chemokine profiles, bacterial/viral infections, and the modulation of associated pro-inflammatory transcriptional and signaling pathways is discussed. Moreover, GSK3 contributes to the resolution of inflammation on multiple levels, e.g., via the regulation of pro-resolving mediators, the clearance of apoptotic immune cells, and tissue repair processes. The influence of GSK3 on the development of different forms of stimulation tolerance is also addressed. Collectively, the role of GSK3 as a kinase balancing the initiation/perpetuation and the amelioration/resolution of inflammation is highlighted.

Ischemic Postconditioning Alleviates Intestinal Ischemia-Reperfusion Injury by Enhancing Autophagy and Suppressing Oxidative Stress through the Akt/GSK-3β/Nrf2 Pathway in Mice

Aims

Ischemic postconditioning (IPO) has a strong protective effect against intestinal ischemia-reperfusion (IIR) injury that is partly related to autophagy. However, the precise mechanisms involved are unknown.

Methods

C57BL/6J mice were subjected to unilateral IIR with or without IPO. After 45 min ischemia and 120 min reperfusion, intestinal tissues and blood were collected for examination. HE staining and Chiu's score were used to evaluate pathologic injury. We test markers of intestinal barrier function and oxidative stress. Finally, we used WB to detect the expression of key proteins of autophagy and the Akt/GSK-3β/Nrf2 pathway.

Results

IPO significantly attenuated IIR injury. Expression levels of LC3 II/I, Beclin-1, and p62 were altered during IIR, indicating that IPO enhanced autophagy. IPO also activated Akt, inhibited GSK-3β/Nrf2 pathway.

Conclusion

Our study indicates that IPO can ameliorate IIR injury by evoking autophagy, activating Akt, inactivating GSK-3β, and activating Nrf2. These findings may provide novel insights for the alleviation of IIR injury.β/Nrf2 pathway.

Paeoniflorin Inhibits Mesangial Cell Proliferation and Inflammatory Response in Rats With Mesangial Proliferative Glomerulonephritis Through PI3K/AKT/GSK-3β Pathway

Mesangial proliferative glomerulonephritis (MPGN) is the most common type of chronic kidney disease in China, characterized by mesangial cell proliferation and inflammatory response. Paeoniflorin, an effective composition extracted from Radix Paeoniae Alba, has been used for various kinds of kidney diseases. However, there are no studies reporting the effects of paeoniflorin on MPGN. The present study aims to investigate whether paeoniflorin plays a role in MPGN and confirm the underlying molecular mechanisms. Our results manifested that paeoniflorin strongly restrained 24 h urinary protein and promoted renal function and dyslipidemia in a MPGN rat model. Moreover, paeoniflorin attenuated mesangial cell proliferation and inflammation both in MPGN rats and human mesangial cells (HMCs) treated with lipopolysaccharide (LPS). In detail, paeoniflorin decreased the number of mesangial cells and expressions of proliferation marker Ki67 in MPGN rats. Paeoniflorin also inhibited HMC proliferation and blocked cell cycle progression. In addition, the contents of inflammatory factors and the expressions of macrophage marker iNOS were decreased after paeoniflorin treatment. Furthermore, we found that the protective effect of paeoniflorin was accompanied by a strong inhibition of the phosphatidylinositol 3-kinase (PI3K)/AKT/glycogen synthase kinase (GSK)-3β pathway. Paeoniflorin enhanced the inhibitory effect of PI3K inhibitor LY294002 and suppressed the activated effect of PI3K agonist insulin-like growth factor 1 (IGF-1) on PI3K/AKT/GSK-3β pathway. In conclusion, these results demonstrated that paeoniflorin ameliorates MPGN by inhibiting mesangial cell proliferation and inflammatory response through the PI3K/AKT/GSK-3β pathway.

Improving the anti-keloid outcomes through liposomes loading paclitaxel-cholesterol complexes

Background

Keloids represent benign fibroproliferative tumors which result from elevated expression of inflammation. Paclitaxel (PTX) was an effective chemotherapeutic agent and has been reported to have anti-fibrotic effects, but the strong hydrophobicity brings a challenge for its clinical application.

Purpose

The objective of this study was to improve the water solubility of PTX and investigate its anti-keloid effects.

Methods

We prepared a PTX-cholesterol-loaded liposomes (PTXL) by thin film evaporation fashion and characterized their physicochemical properties. We also investigated the effects of PTX on proliferation, invasion and fibrosis of keloid fibroblasts in vitro and in vivo.

Results

The prepared PTXL have a spherical appearance, a particle size of 101.43 nm and a zeta potential of −41.63 mV. PTXL possessed a high drug entrapment efficiency of 95.63% and exhibited a good stability within 30 days. The drugs in PTXL were released in a slow and sustained mode. The PTXL could be effectively uptaken into human keloids fibroblast (HKFs) in a time-dependent manner. In vitro, PTXL showed better ability on inhibiting cell proliferation, migration and invasion, and effectively on promoting apoptosis and arresting cell cycle in G₂/M phase compared to PTX. Meanwhile, in vivo studies indicated that the PTXL had better performance on inhibiting the keloids growth compared to the PTX in keloid-bearing BALB/c nude mice model. Finally, we found PTX treatment suppressed the production of tumor necrosis factor alpah (TNF-α), interleukin 6 (IL-6) and transforming growth factor beta (TGF-β) and inhibited the expression of alpha smooth muscle actin (α-SMA) and collagen I in HKFs. The activation of protein kinase B (AKT)/glycogen synthase kinase 3 beta (GSK3β) signaling pathway also blocked by PTX in cultured HKFs and keloid tissues. LY294002, a PI3K (phosphatidylinositol 3-kinase)/AKT inhibitor, also suppressed the expression of TNF-α, IL-6 and TGF-β, and simultaneously, reduced the production of α-SMA and collagen I in HKFs. The inhibition of AKT/GSK3β signaling pathway contribute to inhibit the generation of fibrogenic cytokines by PTXL on ameliorating fibrosis progress in keloids.

Conclusion

Our results suggested that the developed PTXL would become a promising therapeutic agent in the field of anti-keloid therapy.

Detection of GSK-3β activation index in pediatric chronic tonsillitis is an indicator for chronic recurrent inflammation

PURPOSE

Chronic tonsillitis (TC) is among the most common bacterial diseases in pediatric otolaryngology. We aimed to evaluate the expression of glycogen synthase kinase 3β (GSK-3β) in a cohort of children with chronic tonsillitis (TC), and the correlation between GSK-3β activity index and inflammatory profiles of TC.

MATERIALS AND METHODS

The expression of GSK-3β was comparably evaluated between children with TC (n = 26) and tonsillar hypertrophy (TH, n = 26). GSK-3β expression was detected by immunohistochemistry, RT-qPCR, and Western blot. The inflammatory profiles between the TC and TH groups were also evaluated.

RESULTS

We found that while GSK-3β was highly expressed in both TC and TH groups, no significant difference were detected at mRNA and protein levels between groups. The protein level of p-GSK-3β was significantly lower in the TC group as compared to the TH group. Additionally, the inflammatory markers, including NF-κB, T-bet, and IFN-γ were higher in the TC group compared to TH group. The GSK-3β activation index was positively correlated with the levels of NF-κB, T-bet, and IFN-γ in the TC group.

CONCLUSIONS

Our findings suggested that GSK-3β activation index was demonstrated to be a clinically applicable indicator for chronic recurrent inflammation in pediatric TC.