PTEN promotes apoptosis of H2O2‑injured rat nasal epithelial cells through PI3K/Akt and other pathways

A SERS-Based Dual-Parameter Monitoring Nanoprobe of ROS and PI3K/Akt during Ginsenoside Rg3-Induced Cell Apoptosis

Both the reactive oxygen species (ROS) level and Phosphatidylinositol 3 Kinase (PI3K) protein content are two crucial parameters for characterizing states of cell apoptosis. Current methods measure these parameters with two different techniques, respectively, which usually lead to evaluation contingency. Ginsenoside Rg3 exhibits an excellent anticancer effect, which is enacted by the Phosphatidylinositol 3 Kinase/Protein Kinase B (PI3K/Akt) pathway involving ROS; however, the precise mechanism that induces cell apoptosis remains unknown. This is due to the lack of information on quantitative intracellular ROS and PI3K. Here, we used a surface-enhanced Raman scattering (SERS)-based boric acid nanoprobe to monitor the intracellular ROS level and phosphatidylinositol-3,4,5-triphosphate (PI(3,4,5)P₃) content, which reflects the regulatory effect of the PI3K/Akt pathway. After treatment with ginsenoside Rg3, the PI3K/Akt content first increased and then decreased as the ROS level increased. Moreover, when the ROS level significantly increased, the mitochondrial membrane potential reduced, thus indicating the dynamic regulation effect of intracellular ROS level on the PI3K/Akt pathway. Importantly, in addition to avoiding evaluation contingency, which is caused by measuring the aforementioned parameters with two different techniques, this SERS-based dual-parameter monitoring nanoprobe provides an effective solution for simultaneous ROS level and PI3K content measurements during cell apoptosis. Furthermore, the intracellular ROS level was also able to have a dynamic regulatory effect on the PI3K/Akt pathway, which is essential for studying ROS/PI3K/Akt-pathway-related cell apoptosis and its activation mechanism.

Formononetin ameliorates IL‑13‑induced inflammation and mucus formation in human nasal epithelial cells by activating the SIRT1/Nrf2 signaling pathway

Formononetin has proven to be anti‑inflammatory and able to alleviate symptoms of certain allergic diseases. The present study aimed to determine and elucidate the potential effects of formononetin in allergic rhinitis. JME/CF15 cells were pretreated with formononetin at different doses, followed by stimulation with IL‑13. Cell Counting Kit‑8 assay was performed to determine the cytotoxicity of formononetin. The expression levels of inflammation‑related proteins, histamine, IgE, TNF‑α, IL‑1β, IL‑6, granulocyte‑macrophage colony‑stimulating factor and eotaxin in IL‑13‑stimulated JME/CF15 cells were detected using ELISAs. The expression levels of phosphorylated‑NF‑κB p65, NF‑κB p65 and cyclooxygenase‑2 (Cox‑2) were analyzed using western blotting. Reverse transcription‑quantitative PCR, western blotting and immunofluorescence were performed to measure the levels of mucin 5AC oligomeric mucus/gel‑forming. Expression levels of sirtuin 1 (SIRT1) and nuclear erythroid factor 2‑related factor 2 (Nrf2) proteins were also measured using western blotting. The results of the present study revealed that formononetin exerted no cytotoxic effect on the viability of JME/CF15 cells. Following stimulation of JME/CF15 cells with IL‑13, formononetin suppressed the upregulated expression levels of proinflammatory cytokines. IL‑13‑induced formation of mucus was also attenuated by formononetin treatment. Furthermore, it was found that the SIRT1/Nrf2 signaling pathway was activated in formononetin‑treated JME/CF15 cells, whereas treatment with the SIRT1 inhibitor, EX527, reversed the effects of formononetin on IL‑13‑induced inflammation and mucus formation in JME/CF15 cells. In conclusion, the findings of the current study indicated that formononetin may activate the SIRT1/Nrf2 signaling pathway, thereby inhibiting IL‑13‑induced inflammation and mucus formation in JME/CF15 cells. These results suggested that formononetin may represent a promising agent for the treatment of allergic rhinitis.

Resveratrol upregulates miR-455-5p to antagonize cisplatin ototoxicity via modulating the PTEN-PI3K-AKT axis

Resveratrol is a non-flavonoid polyphenol compound that exists in many plants, and is considered an antitoxin. This study explores the effects from the regulation of miR-455-5p by resveratrol on cisplatin-induced ototoxicity via the PTEN-PI3K-AKT signaling pathway. For this, House Ear Institute-Organ of Corti 1 (HEI-OC1) cells were transfected with miR-455-5p inhibitor and treated with cisplatin and resveratrol, then cell proliferation, apoptosis, and oxidative stress were evaluated. A mouse model of hearing loss was established, and these mice were treated with cisplatin, resveratrol, or cisplatin combined with resveratrol, by intraperitoneal injection. The auditory brainstem response (ABR) threshold was measured, and hair cells were examined using immunofluorescence staining. The expression levels of miR-455-5p, PTEN, and PI3K/Akt proteins were examined. The results from our in-vitro experiments indicate that resveratrol promoted viability and reduced apoptosis and oxidative stress in cisplatin-induced HEI-OC1 cells. Resveratrol upregulated miR-455-5p, downregulated PTEN, and activated the PI3K-Akt axis. These effects of resveratrol were reversed by knock-down of miR-455-5p. The results from our in-vivo experiments indicate that resveratrol protected hearing and inhibited the hair-cell injury caused by cisplatin ototoxicity. Resveratrol also upregulated miR-455-5p, downregulated PTEN, and activated the PTEN-PI3K-Akt axis in cochlear tissues from cisplatin-treated mice. These results indicate that resveratrol upregulates miR-455-5p to target PTEN and activate the PI3K-Akt signaling pathway to counteract cisplatin ototoxicity.

Cigarette Smoke Extract Stimulates MMP-2 Production in Nasal Fibroblasts via ROS/PI3K, Akt, and NF-κB Signaling Pathways

Cigarette smoke exposure has been shown to be associated with chronic rhinosinusitis and tissue remodeling. The present study aimed to investigate the effects of cigarette smoke extract (CSE) on matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) production in nasal fibroblasts and to determine the underlying molecular mechanisms. Primary nasal fibroblasts from six patients were isolated and cultured. After the exposure of fibroblasts to CSE, the expression levels of MMP-2, MMP-9, TIMP-1, and TIMP-2 were measured by real-time PCR, ELISA, and immunofluorescence staining. The enzymatic activities of MMP-2 and MMP-9 were measured by gelatin zymography. Reactive oxygen species (ROS) production was analyzed using dichloro-dihydro-fluorescein diacetate and Amplex Red assays. PI3K/Akt phosphorylation and NF-κB activation were determined by Western blotting and luciferase assay. CSE significantly increased MMP-2 expression and inhibited TIMP-2 expression but did not affect MMP-9 and TIMP-1 expression. Furthermore, CSE significantly induced ROS production. However, treatment with ROS scavengers, specific PI3K/Akt inhibitors, NF-κB inhibitor, and glucocorticosteroids significantly decreased MMP-2 expression and increased TIMP-2 expression. Our results suggest that steroids inhibit CSE-regulated MMP-2 and TIMP-2 production and activation through the ROS/ PI3K, Akt, and NF-κB signaling pathways in nasal fibroblasts. CSE may contribute to the pathogenesis of chronic rhinosinusitis by regulating MMP-2 and TIMP-2 expression.

Spinosin Inhibits Aβ1-42 Production and Aggregation via Activating Nrf2/HO-1 Pathway

The present research work primarily investigated whether spinosin has the potential of improving the pathogenesis of Alzheimer’s disease (AD) driven by β-amyloid (Aβ) overproduction through impacting the procession of amyloid precursor protein (APP). Wild type mouse Neuro-2a cells (N2a/WT) and N2a stably expressing human APP695 (N2a/APP695) cells were treated with spinosin for 24 h. The levels of APP protein and secreted enzymes closely related to APP procession were examined by western blot analysis. Oxidative stress related proteins, such as nuclear factor-erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) were detected by immunofluorescence assay and western blot analysis, respectively. The intracellular reactive oxygen species (ROS) level was analyzed by flow cytometry, the levels of Aβ_1-42 were determined by ELISA kit, and Thioflavin T (ThT) assay was used to detect the effect of spinosin on Aβ_1-42 aggregation. The results showed that ROS induced the expression of ADAM10 and reduced the expression of BACE1, while spinosin inhibited ROS production by activating Nrf2 and up-regulating the expression of HO-1. Additionally, spinosin reduced Aβ_1-42 production by impacting the procession of APP. In addition, spinosin inhibited the aggregation of Aβ_1-42. In conclusion, spinosin reduced Aβ_1-42 production by activating the Nrf2/HO-1 pathway in N2a/WT and N2a/APP695 cells. Therefore, spinosin is expected to be a promising treatment of AD.

miR-338-5p Targets Epidermal Growth Factor-Containing Fibulin-Like Extracellular Matrix Protein 1 to Inhibit the Growth and Invasion of Trophoblast Cells in Selective Intrauterine Growth Restriction

Selective intrauterine growth restriction (sIUGR) is a disorder of monochorionic (MC) twin pregnancies. However, the underlying mechanism remains largely unknown. Trophoblast cells are the major component of the placenta. Dysfunction of trophoblast cells is associated with placental dysfunction. Our previous study identified miR-338-5p is downregulated in placenta tissues sharing larger twins of sIUGR. In the present study, we aimed to investigate the role of miR-338-5p in trophoblast cells and explored its target. Our results further indicated that miR-338-5p was downregulated in placental tissues supporting larger twins of sIUGR, whereas epidermal growth factor-containing fibulin-like extracellular matrix protein 1 (EFEMP1) was upregulated. Moreover, miR-338-5p overexpression suppressed the growth and invasion of trophoblast cells. Importantly, results from luciferase reporter assay demonstrated that miR-338-5p bound on the 3'-UTR of EFEMP1. miR-338-5p suppressed the growth and invasion of trophoblast cells via targeting EFEMP1. Further, miR-338-5p/EFEMP1 might disrupt the function of trophoblast cells via inhibiting the phosphorylation of AKT.

Resveratrol protects the integrity of alveolar epithelial barrier via SIRT1/PTEN/p-Akt pathway in methamphetamine-induced chronic lung injury

Objectives

SIRT1 is an antioxidative factor, but its mechanism in methamphetamine (MA)‐induced lung injury remains unclear. The purpose of this study is to determine whether MA can disrupt the integrity of alveolar epithelial barrier, whether SIRT1 is involved in MA‐induced chronic lung injury and whether Resveratrol (Res) can protect the integrity of alveolar epithelial cells by regulating ROS to activate SIRT1/PTEN/p‐Akt pathway.

Materials and methods

The rats were randomly divided into control group and MA group. Extracted lungs were detected by Western blot, HE staining and immunohistochemistry. The alveolar epithelial cells were treated with MA or/and Res, following by Western blot, LDH leakage assay and flow cytometry. MOE is used for bio‐informatics prediction.

Results

Chronic exposure to MA can cause slower growth ratio of weight, increased RVI and induced lung injury including the reduced number of alveolar sacs and the thickened alveolar walls. MA‐induced apoptosis was associated with SIRT1‐related oxidative stress. Res suppressed ROS levels, activated SIRT1, negatively regulated PTEN, phosphorylated Akt, reduced LDH leakage, increased the expression of ZO‐1 and E‐cadherin and inhibited the apoptosis of alveolar epithelial cells to attenuate MA‐induced higher permeability of alveolar epithelium.

Conclusions

MA disrupted the integrity of alveolar epithelial barrier. Res inhibited oxidative stress and reversed MA‐induced higher permeability and apoptosis of alveolar epithelium by the activation of SIRT1/PTEN/p‐Akt pathway.

TRIM27 promotes the development of esophagus cancer via regulating PTEN/AKT signaling pathway

Background

Tripartite motif‑containing 27 (TRIM27) belongs to the TRIM protein family, which is closely related to the progression of some certain human cancers. Nevertheless, the biological function of TRIM27 in esophageal squamous cell carcinoma (ESCC) is still not clear. The aim of present research is to examine the function of TRIM27 in ESCC cells.

Methods

In the present study, RNA interference (RNAi) and lentiviral vector were used to knockdown and overexpression of TRIM27 in ESCC cells respectively. qRT-PCR and western blot were used to examine the expression of TRIM27 in ESCC cells. Cell counting kit-8 (CCK-8) assay was performed to determine the proliferation of cells.

Results

Our analyses indicated that TRIM27 was a pro-proliferation factor in ESCC cells. Moreover, overexpression of TRIM27 deeply suppressed the apoptosis of ESCC cells and accelerated its glucose uptake. In addition, an AKT inhibitor LY294002 was used to determine the connection between TRIM27 and AKT in ESCC cells. Our results demonstrated that TRIM27 has involved in the PI3/AKT signaling pathway. Moreover, TRIM27 interacted with PTEN and mediated its poly-ubiquitination in ESCC cells. Importantly, the glycolysis inhibitor 3-BrPA also inhibited the effect of TRIM27 on ESCC cells. Hence, TRIM27 also participated in the regulation of energy metabolism in ESCC cells.

Conclusions

This research not only gained a deep insight into the biological function of TRIM27 but also elucidated its potential target and signaling pathway in human ESCC cells.