The protective effect of Macrostemonoside T from Allium macrostemon Bunge against Isoproterenol-Induced myocardial injury via the PI3K/Akt/mTOR signaling pathway

Myocardial injury (MI) signifies a pathological aspect of cardiovascular diseases (CVDs) such as coronary artery disease, diabetic cardiomyopathy, and myocarditis. Macrostemonoside T (MST) has been isolated from Allium macrostemon Bunge (AMB), a key traditional Chinese medicine (TCM) used for treating chest stuffiness and pains. Although MST has demonstrated considerable antioxidant activity in vitro, its protective effect against MI remains unexplored. To investigate MST's effects in both in vivo and in vitro models of isoproterenol (ISO)-induced MI and elucidate its underlying molecular mechanisms. This study established an ISO-induced MI model in rats and assessed H9c2 cytotoxicity to examine MST's impact on MI. Various assays, including histopathological staining, TUNEL staining, immunohistochemical staining, DCFH-DA staining, JC-1 staining, ELISA technique, and Western blot (WB), were utilized to explore the potential molecular mechanisms of MI protection. In vivo experiments demonstrated that ISO caused myocardial fiber disorders, elevated cardiac enzyme levels, and apoptosis. However, pretreatment with MST significantly mitigated these detrimental changes. In vitro experiments revealed that MST boosted antioxidant enzyme levels and suppressed malondialdehyde (MDA) production in H9c2 cells. Concurrently, MST inhibited ISO-induced reactive oxygen species (ROS) production and mitigated the decline in mitochondrial membrane potential, thereby reducing the apoptosis rate. Moreover, pretreatment with MST elevated the expression levels of p-PI3K, p-Akt, and p-mTOR, indicating activation of the PI3K/Akt/mTOR signaling pathway and consequent protection against MI. MST attenuated ISO-induced MI in rats by impeding apoptosis through activation of the PI3K/Akt/mTOR signaling pathway. This study presents potential avenues for the development of precursor drugs for CVDs.

The anti-depression effect and potential mechanism of the petroleum ether fraction of CDB: Integrated network pharmacology and metabolomics

The combination of Chaidangbo (CDB) is an antidepressant traditional Chinese medicine (TCM) prescription simplified by Xiaoyaosan (a classic antidepressant TCM prescription) through dismantling research, which has the effect of dispersing stagnated liver qi and nourishing blood in TCM theory. Although the antidepressant effect of CBD has been confirmed in animal studies, the material basis and possible molecular mechanism for antidepressant activity in CBD have not been clearly elucidated. Herein, we investigated the effects and potential mechanisms of CDB antidepressant fraction (petroleum ether fraction of CDB, PEFC) on chronic unpredictable mild stress (CUMS)-induced depression-like behavior in mice using network pharmacology and metabolomics. First, a UPLC-QE/MS was employed to identify the components of PEFC. To extract active ingredients, SwissADME screening was used to the real PEFC components that were found. Potential PEFC antidepressant targets were predicted based on a network pharmacology approach, and a pathway enrichment analysis was performed for the predicted targets. Afterward, a CUMS mouse depression model was established and LC-MS-based untargeted hippocampal metabolomics was performed to identify differential metabolites, and related metabolic pathways. Finally, the protein expressions in mouse hippocampi were determined by Western blot to validate the network pharmacology and metabolomics deduction. A total of 16 active compounds were screened in SwissADME that acted on 73 core targets of depression, including STAT3, MAPKs, and NR3C1; KEGG enrichment analysis showed that PEFC modulated signaling pathways such as PI3K-Akt signaling pathway, endocrine resistance, and MAPK to exert antidepressant effects. PEFC significantly reversed abnormalities of hippocampus metabolites in CUMS mice, mainly affecting the synthesis and metabolism of glycine, serine, and threonine, impacting catecholamine transfer and cholinergic synapses and regulating the activity of the mTOR signaling pathway. Furthermore, Western blot analysis confirmed that PEFC significantly influenced the main protein levels of the PI3K/Akt/mTOR signaling pathways in the hippocampus of mice subjected to CUMS. This study integrated metabolomics, network pharmacology and biological verification to explore the potential mechanism of PEFC in treating depression, which is related to the regulation of amino acid metabolism dysfunction and the activation of PI3K/Akt/mTOR signaling pathways in the hippocampus. The comprehensive strategy also provided a reasonable way for unveiling the pharmacodynamic mechanisms of multi-components, multi-targets, and multi-pathways in TCM with antidepressant effect.

Exploring the Mechanism of KLF15 on the Biological Activity and Autophagy of Gastric Cancer Cells based on PI3K/Akt/Mtor Signaling Pathway

OBJECTIVE

To explore the mechanism of KLF15 on the biological activity and autophagy of gastric cancer cells based on the PI3K/Akt/mTOR signaling pathway.

MATERIAL AND METHODS

The gastric cancer AGS cells were divided into the Con group, pcDNANC group, pcDNA-KLF15 group, LY294002 group and IGF-1 group. RT-PCR was used to detect the expression of KLF15 in human gastric mucosal cells and gastric cancer cells; MTT method to detect cell proliferation; Transwell method to detect cell invasion; flow cytometry to detect cell apoptosis; Western blotting to detect PI3K, Akt, mTOR in cells, LC3, Beclin1, p62 protein expression.P<0.05 was used to indicate statistical significance.

RESULTS

Compared with the human gastric mucosal cell line GES-1 cells, the expression of KLF15 in human gastric cancer cell lines MKN-28, MFC, SCG-7901 and AGS cells was significantly decreased, And the expression of KLF15 in AGS cells, was the lowest (P=0.006). Compared with the Con group, The expression of KLF15 in the cells of the PCDNA-KLF15 group was significantly increased (P=0.018); There was no significant difference in the expression of KLF15 between the Con group and the PCDNA-NC group (P=0.225). Compared with the Con group, the proliferation and invasion abilities of the cells in the pcDNA-KLF15 group were significantly reduced, And the apoptosis ability was significantly increased (P=0.019). The ratio of LC3II/LC31 and the expression of Beclin1 Protein in the control group were significantly higher than those in the Con group (P=0.017).

CONCLUSION

Overexpression of KLF15 can inhibit the proliferation and invasion of Gastric cancer cells and promote cell apoptosis and autophagy, and its mechanism may be related to the regulation of the PI3K/Akt/mTOR signaling pathway.

Novel protein C6ORF120 promotes liver fibrosis by activating hepatic stellate cells through the PI3K/Akt/mTOR pathway

BACKGROUND AND AIM

The role of C6ORF120 in promoting CCL4-induced hepatic fibrosis and its possible mechanisms were explored in C6orf120 knockout rats (C6orf120-/-) and LX-2 cells (a type of human hepatic stellate cell line).

METHODS

In vivo experiments, wild-type and C6orf120-/- rats were used to investigate the function of C6ORF120. In the in vitro experiments, C6ORF120 recombinant protein (rC6ORF120) at a concentration of 200 ng/mL was used to stimulate LX-2 cells. Sirius Red staining, Masson staining, western blotting, polymerase chain reaction, immunohistochemistry, and immunofluorescence were used to explore fibrosis-associated factors.

RESULTS

C6orf120-/- rats showed mild fibrosis and liver injury in the CCL4-induced liver fibrosis model. Furthermore, RNA-seq revealed that C6orf120-/- rats had less extracellular matrix deposition and activated stellate cells. Consistent with the in vivo, the rC6ORF120 induced LX-2 cell activation. Moreover, mechanistic studies revealed that the p-PI3K/PI3K, p-Akt/Akt, and p-mTOR/mTOR levels were significantly elevated and LY294002 (a PI3K/Akt/mTOR typical pathway inhibitor) reversed the function of C6ORF120 in activating LX-2 cells.

CONCLUSION

C6ORF120 could activate hepatic stellate cells and promote hepatic fibrosis via the PI3K/Akt/mTOR signaling pathway.

Chanling Gao suppresses colorectal cancer via PI3K/Akt/mTOR pathway modulation and enhances quality of survival

The Chinese medicine formula Chanling Gao (CLG) exhibits significant tumor inhibitory effects in colorectal cancer (CRC) nude mice. However, the detailed mechanisms remain elusive. CRC in situ nude mouse models were treated with CLG. Small animal magnetic resonance imaging (MRI) tracked tumor progression, and overall health metrics such as food and water intake, body weight, and survival were monitored. Posttreatment, tissues and blood were analyzed for indicators of tumor inhibition and systemic effects. Changes in vital organs were observed via stereoscope and hematoxylin-eosin staining. Immunohistochemistry quantified HIF-1α and P70S6K1 protein expression in xenografts. Double labeling was used to statistically analyze vascular endothelial growth factor (VEGF) and CD31 neovascularization. Enzyme-linked immunosorbent assay was used to determine the levels of VEGF, MMP-2, MMP-9, IL-6, and IL-10 in serum, tumors, and liver. Western blotting was used to assess the expression of the PI3K/Akt/mTOR signaling pathway-related factors TGF-β1 and smad4 in liver tissues. CLG inhibited tumor growth, improved overall health metrics, and ameliorated abnormal blood cell counts in CRC nude mice. CLG significantly reduced tumor neovascularization and VEGF expression in tumors and blood. It also suppressed HIF-1α, EGFR, p-PI3K, Akt, p-Akt, and p-mTOR expression in tumors while enhancing PTEN oncogene expression. Systemic improvements were noted, with CLG limiting liver metastasis, reducing pro-inflammatory cytokines IL-6 and IL-10 in liver tissues, decreasing MMP-2 in blood and MMP-2 and MMP-9 in tumors, and inhibiting TGF-β1 expression in liver tissues. CLG can enhance survival quality and inhibit tumor growth in CRC nude mice, likely through the regulation of the PI3K/Akt/mTOR signaling pathway.

Rapamycin mitigates inflammation-mediated disc matrix homeostatic imbalance by inhibiting mTORC1 and inducing autophagy through Akt activation

Background

Low back pain is a global health problem that originated mainly from intervertebral disc degeneration (IDD). Autophagy, negatively regulated by the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway, prevents metabolic and degenerative diseases by removing and recycling damaged cellular components. Despite growing evidence that autophagy occurs in the intervertebral disc, the regulation of disc cellular autophagy is still poorly understood.

Methods

Annulus fibrosus (rAF) cell cultures derived from healthy female rabbit discs were used to test the effect of autophagy inhibition or activation on disc cell fate and matrix homeostasis. Specifically, different chemical inhibitors including rapamycin, 3-methyladenine, MK-2206, and PP242 were used to modulate activities of different proteins in the PI3K/Akt/mTOR signaling pathway to assess IL-1β-induced cellular senescence, apoptosis, and matrix homeostasis in rAF cells grown under nutrient-poor culture condition.

Results

Rapamycin, an inhibitor of mTOR complex 1 (mTORC1), reduced the phosphorylation of mTOR and its effector p70/S6K in rAF cell cultures. Rapamycin also induced autophagic flux as measured by increased expression of key autophagy markers, including LC3 puncta number, LC3-II expression, and cytoplasmic HMGB1 intensity and decreased p62/SQSTM1 expression. As expected, IL-1β stimulation promoted rAF cellular senescence, apoptosis, and matrix homeostatic imbalance with enhanced aggrecanolysis and MMP-3 and MMP-13 expression. Rapamycin treatment effectively mitigated IL-1β-mediated inflammatory stress changes, but these alleviating effects of rapamycin were abrogated by chemical inhibition of Akt and mTOR complex 2 (mTORC2).

Conclusions

These findings suggest that rapamycin blunts adverse effects of inflammation on disc cells by inhibiting mTORC1 to induce autophagy through the PI3K/Akt/mTOR pathway that is dependent on Akt and mTORC2 activities. Hence, our findings identify autophagy, rapamycin, and PI3K/Akt/mTOR signaling as potential therapeutic targets for IDD treatment.

Inhibition of Multifunctional Protein p32/C1QBP Promotes Cytostatic Effects in Colon Cancer Cells by Altering Mitogenic Signaling Pathways and Promoting Mitochondrial Damage

The protein p32 (C1QBP) is a multifunctional and multicompartmental homotrimer that is overexpressed in many cancer types, including colon cancer. High expression levels of C1QBP are negatively correlated with the survival of patients. Previously, we demonstrated that C1QBP is an essential promoter of migration, chemoresistance, clonogenic, and tumorigenic capacity in colon cancer cells. However, the mechanisms underlying these functions and the effects of specific C1QBP protein inhibitors remain unexplored. Here, we show that the specific pharmacological inhibition of C1QBP with the small molecule M36 significantly decreased the viability rate, clonogenic capacity, and proliferation rate of different colon cancer cell lines in a dose-dependent manner. The effects of the inhibitor of C1QBP were cytostatic and non-cytotoxic, inducing a decreased activation rate of critical pro-malignant and mitogenic cellular pathways such as Akt-mTOR and MAPK in RKO colon cancer cells. Additionally, treatment with M36 significantly affected the mitochondrial integrity and dynamics of malignant cells, indicating that p32/C1QBP plays an essential role in maintaining mitochondrial homeostasis. Altogether, our results reinforce that C1QBP is an important oncogene target and that M36 may be a promising therapeutic drug for the treatment of colon cancer.

Intervention effect of Lycium barbarum polysaccharide on lead-induced kidney injury mice and its mechanism: A study based on the PI3K/Akt/mTOR signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional medicinal application of Lycium barbarum is centered on the improvement of eyesight, as well as the nourishment of liver and kidney functions. Lycium barbarum polysaccharide (LBP), serving as the principal active constituent of Lycium barbarum, has been identified as the main contributor to these beneficial effects. Previous studies have indicated that Lycium barbarum polysaccharide exhibits a renoprotective effect against lead-induced injury, but its mechanism and efficacy remain unclear.

AIM OF THE STUDY

The objective of this study was to examine the effectiveness of LBP in preventing lead-induced renal injury and investigate both the toxic mechanism of lead-induced renal injury and the efficacy mechanism of LBP against it, with a focus on the PI3K/AKT/mTOR signaling pathway.

MATERIALS AND METHODS

The drug effect and mechanism of LBP on lead-induced kidney injury were investigated by administering positive drugs and LBP to mice with established lead-induced kidney injury.

RESULTS

The renal function of mice with lead-induced renal injury was significantly restored, renal tissue lesions and renal mitochondrial damage were delayed, a disorder of hematological parameters induced by lead was improved, the increase of lead-induced renal index was reduced, and the body weight of mice with lead-induced renal injury was increased by the LBP intervention, as revealed by the results of pharmacodynamic experiments. Based on PI3K /AKT /mTOR signaling pathway, the toxic mechanism of lead-induced kidney injury and the pharmacodynamic mechanism of LBP against lead-induced kidney injury were studied. The results showed that lead could activate the TLR4 receptor, and then activate PI3K /AKT /mTOR signaling pathway, inhibit autophagy of kidney tissue cells, and enhance apoptosis of kidney tissue cells to induce kidney injury; LBP inhibits the activation of TLR4 receptor, which in turn inhibits the PI3K/AKT/mTOR signaling pathway, enhances the autophagy of kidney tissue cells, reduces the apoptosis of kidney tissues, and delays lead-induced kidney injury.

The role and mechanism of AZD5363 anti-leukemia activity in T-cell acute lymphoblastic leukemia

BACKGROUND

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive and heterogeneous hematologic malignancy. Chemotherapy resistance and refractory relapses are the most important challenges in T-ALL. PI3K/Akt/mTOR pathway has been implicated in regulating cell survival, T-ALL development and resistance to chemotherapy. We explored the effects of AZD5363 (a potent pan-Akt inhibitor) alone and in combination with autophagy inhibitor hydroxycholoroquine sulfate (HCQ) in cultured CCRF-CEM, Jurkat and PF382 cells and a T-ALL xenograft mouse model.

METHODS

A xenograft mouse model was used to investigate the effect of AZD5363 on T-ALL progression. MTT assay, flow cytometry, siRNA, transmission electron microscopy and western blotting were performed in cultured CCRF-CEM, Jurkat and PF382 cells. The interaction between AZD5363 and HCQ was explored by molecular docking.

RESULTS

AZD5363 delayed T-ALL progression and increased the expression of cleaved caspase-3 and LC3B-II in mice. AZD5363 decreased cells viability by arresting cell cycle in the G1 phase and inducing apoptosis, and, significantly increased the number of autophagosomes (p < 0.01). The increased expression of cleaved caspase-3 and LC3B-II, and phosphorylation of Akt and mTOR were significantly, inhibited by AZD5363. HCQ blocked AZD5363-induced autophagy and enhanced AZD5363-induced cell death (p < 0.01).

CONCLUSIONS

AZD5363 suppressed T-ALL progression and its anti-leukemia activity was enhanced by HCQ in T-ALL cells, which might provide a potential therapeutic strategy for human T-ALL.

Jingfang Granules () alleviates bleomycin-induced acute lung injury through regulating PI3K/Akt/mTOR signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Acute lung injury is a kind of clinical emergency severe syndrome which might trigger acute respiratory distress syndrome. Jingfang Granules () is a traditional Chinese medicine which has been proven to improve acute lung injury induced by bleomycin through inhibiting recruitment and overactive of inflammation. However, the potential mechanisms are still not well evaluated.

AIM OF STUDY

The aim of this study was to evaluate the protective function of Jingfang Granules on bleomycin caused acute lung injury and further discuss the potential pharmacological mechanisms.

MATERIALS AND METHODS

C57BL/6J mice were intratracheal injected bleomycin to induce model with acute lung injury. The protective impact of Jingfang Granules on acute lung injury and lung fibrosis triggered by bleomycin were evaluated through detecting mice body weight, lung appearance, lung index, and histopathology. The potential pharmacological mechanism of Jingfang Granules in treating acute lung injury was further elucidated by the methods of network pharmacology, proteomics, metabolomics, as well as western blot. Additionally, the network pharmacology analysis and molecular docking technology were integrated to investigate the targets of Jingfang Granules improving acute lung injury.

RESULTS

Our results indicated that Jingfang Granules effectively protected mice from acute lung injury induced by bleomycin, which was confirmed by higher body weight, lower pulmonary edema and lung index, and improved pathology and fibrosis of lung tissue compared to model group. Proteomics, western blot, and metabolomics were integrated and the results confirmed that Jingfang Granules regulated the Glycolysis/Gluconogenesis and Pyruvate metabolism through downregulating the PI3K/Akt/mTOR signaling pathway. The network pharmacology analysis and molecular docking technology results showed that the targets of Jingfang Granules for treating acute lung injury were enriched in the PI3K/Akt signaling pathway, which included 7 target proteins such as MAPK1, MAPK3, JAK2, HRAS, EGFR, PIK3R1, and PIK3CA.

CONCLUSION

This study indicates that Jingfang Granules displays a markedly protective effect on acute lung injury caused by bleomycin through downregulating PI3K/Akt/mTOR signaling pathway, which in turn regulates Glycolysis/Gluconogenesis and Pyruvate metabolism.

Combining network pharmacology and experimental verification to reveal the mechanism of Chaigui granules in the treatment of depression through PI3K/Akt/mTOR signaling pathways

INTRODUCTION

Chaigui granules are a novel manufactured traditional Chinese antidepressant medicine, which is originated from the ancient classical prescription of Xiaoyaosan. It ameliorated depression-like behavior and concomitant symptoms in animal models. But its antidepressant mechanism is still unclear. Therefore, network pharmacology and molecular biology were used to explore underlying antidepressant mechanism in this study.

METHODS

Firstly, network pharmacology was used to screen main active ingredients and potential targets in the treatment of depression with Chaigui granules, and to perform pathway enrichment analysis. Secondly, chronic and unpredictable mild stress-induced depression model rats were used, and behavioral tests were used to evaluate the antidepressant effect of Chaigui granules. Finally, the core targets and key pathways predicted by network pharmacology were validated by qRT-PCR and Western blot to determine the relevant gene and protein expression levels in rat hippocampus.

RESULTS

The results of network pharmacology indicated that the PI3K/Akt signaling pathway may play a key role in antidepressant of Chaigui granules. The results of animal experiments showed that Chaigui granules significantly modulated behavioral indicators. Subsequently, the upregulation of relative mRNA levels of mTOR, Akt and PI3K and downregulation of GSK-3β and FoxO3a were observed in rat hippocampus by molecular biology diagnosis. In addition, the decreased expression of Akt and mTOR in CUMS rats hippocampus was significantly reversed, and the expression levels of GSK-3β and FoxO3a were upregulated.

CONCLUSIONS

Based on the results of network pharmacology and animal experiment validation, Chaigui granules may reverse CUMS-induced depression-like behavior in rats through PI3K/Akt/mTOR signaling pathway.

[Protective effect of Shenfu Injection on regulation of autophagy in rats with chronic heart failure based on PI3K/Akt/mTOR pathway]

This study aimed to investigate the mechanism and target sites of Shenfu Injection in the intervention of chronic heart fai-lure based on the PI3K/Akt/mTOR autophagy signaling pathway. The chronic heart failure model was induced in rats by subcutaneous injection of isoproterenol. The model rats were randomly divided into model group, Shenfu Injection group, and 3-methyladenine autophagy inhibitor(3-MA) group. A normal group was also set up. After 15 days of administration, cardiac function indexes of the rats were detected by echocardiography. The serum N-terminal pro-B-type natriuretic peptide(NT-proBNP) levels were measured using the ELISA. HE and Masson staining was performed to observe the morphological changes in myocardial tissues, and electron microscopy was used to observe the autophagosomes in myocardial tissues. Western blot was conducted to measure the changes in autophagy-related proteins(LC3 Ⅱ/Ⅰ and p62), PI3K, Akt, mTOR, and phosphorylation levels. The results showed that compared with normal group, model group in rats led to reduced cardiac function, significant activation of cardiac autophagy, increased fibrotic lesions in myocardial tissues, structural disorder of the myocardium, increased autophagosomes, and cytoplasmic vacuolization. Compared with model group, Shenfu Injection group in rats led to cardiac function significantly improved, myocardial fibrosis decreased, and the number of autophagosomes and cytoplasmic vacuolization decreased. The phosphorylation levels of PI3K, Akt, and mTOR were significantly increased(P<0.01). In the 3-MA group, autophagy was inhibited through the activation of the PI3K/Akt/mTOR signaling pathway, resulting in improved cardiac function, reduced myocardial fibrosis, and no significant cytoplasmic vacuolization. The findings suggest that Shenfu Injection can activate the PI3K/Akt/mTOR signaling pathway and inhibit autophagy, thereby improving cardiac function.

Tanshinone ⅡA participates in the treatment of endometriosis by regulating adhesion, invasion, angiogenesis and inhibition of PI3K/Akt/mTOR signaling pathway

Endometriosis (EMs) is a common gynecological disorder characterized by abnormal growth of the endometrial stroma and glands outside the uterus. Tanshinone IIA, the active component of Chinese medicine Danshen (Salvia miltiorrhiza Bge.), has a number of pharmacological effects such as anti‑inflammation and anti‑oxidation and serves a significant role in the treatment of EMs. In the present study, network pharmacology and experimental validation were used to elucidate the potential mechanism of tanshinone IIA for treating EMs. Several databases were used to collect information on EMs and tanshinone IIA and cross‑targets for tanshinone IIA and EMs finally obtained. A total of 64 common targets were found between tanshinone IIA and EMs. Subsequently, a protein‑protein interaction network was constructed, a total of 14 core targets were screened for enrichment analysis. Furthermore, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were performed. The network pharmacology showed that intercellular adhesion molecule (ICAM)‑1, MMP‑9 and VEGF are the core targets while PI3K/AKT pathway and mTOR pathway are the main signaling pathways through which tanshinone IIA regulates relevant biological processes to intervene in EMs. Finally, the therapeutic role and mechanism of tanshinone IIA on EMs was verified in vivo. Female Sprague‑Dawley rats were treated by autologous transplantation to establish EMs. Serum inflammatory factors were detected by enzyme‑linked immunosorbent assay (ELISA). The expression of ICAM‑1, MMP‑9 and VEGF in ectopic endometrial tissues of rats was determined by immunohistochemical. The expression of PI3K/Akt/mTOR pathway‑related proteins and genes was detected by western blotting and quantitative PCR. It was found that tanshinone IIA treatment significantly decreased the formation of ectopic endometrium by reducing serum levels of TNF‑α and IL‑1β, and down regulating the levels of ICAM‑1, MMP‑9 and VEGF in ectopic uterine tissue. In addition, tanshinone IIA can also block the activation of PI3K/Akt/mTOR signaling pathway by reducing the expression of related proteins and genes. In conclusion, tanshinone IIA can regulate adhesion, invasion and angiogenesis, thereby improving the pathological morphology of ectopic endometrium and inhibiting the formation of ectopic lesions. The PI3K/Akt/mTOR signaling pathway may play a key role in controlling this process.

Edaravone Dexborneol Alleviates Neuroinflammation by Reducing Neuroglial Cell Proliferation and Suppresses Neuronal Apoptosis/Autophagy in Vascular Dementia Rats

More and more evidence shows that the pathological mechanism of vascular dementia (VD) is closely related to oxidative stress injury, cell apoptosis, autophagy, inflammatory response, excitatory amino acid toxicity, synaptic plasticity change, calcium overload, and other processes. Edaravone dexborneol (EDB) is a new type of neuroprotective agent that can improve the neurological damage caused by an ischemic stroke. Previous studies showed that EDB has effects on synergistic antioxidants and induces anti-apoptotic responses. However, it remains unclear whether EDB can affect apoptosis and autophagy by activating the PI3K/Akt/mTOR signaling pathway and its impact on the neuroglial cells. In this study, we established the VD model of rats by bilateral carotid artery occlusion to explore the neuroprotective effect of EDB and its mechanism. Morris Water Maze test was applied to assess the cognitive function of rats. H&E and TUNEL staining were applied to observe the cellular structure of the hippocampus. Immunofluorescence labeling was used to observe the proliferation of astrocytes and microglia. ELISA was applied to examine the levels of TNF-α, IL-1β and IL-6, and RT-PCR was applied to examine their mRNA expression levels. Western blotting was applied to examine apoptosis-related proteins (Bax, Bcl-2, Caspase-3), autophagy-related proteins (Beclin-1, P62, LC3B), PI3K/Akt/mTOR signaling pathway proteins and their phosphorylation levels. The results indicated that EDB ameliorates learning and memory in rats subjected to the VD model, alleviates neuroinflammatory response by reducing the proliferation of the neuroglial cell and inhibits apoptosis and autophagy, which may be mediated by the PI3K/Akt/mTOR signaling pathway.

Neuroprotective potential of trimetazidine against tramadol-induced neurotoxicity: role of PI3K/Akt/mTOR signaling pathways

Tramadol (TRA) causes neurotoxicity whereas trimetazidine (TMZ) is neuroprotective. The potential involvement of the PI3K/Akt/mTOR signaling pathway in the neuroprotection of TMZ against TRA-induced neurotoxicity was evaluated. Seventy male Wistar rats were divided into groups. Groups 1 and 2 received saline or TRA (50 mg/kg). Groups 3, 4, and 5 received TRA (50 mg/kg) and TMZ (40, 80, or 160 mg/kg) for 14 days. Group 6 received TMZ (160 mg/kg). Hippocampal neurodegenerative, mitochondrial quadruple complex enzymes, phosphatidylinositol-3-kinases (PI3Ks)/protein kinase B levels, oxidative stress, inflammatory, apoptosis, autophagy, and histopathology were evaluated. TMZ decreased anxiety and depressive-like behavior induced by TRA. TMZ in tramadol-treated animals inhibited lipid peroxidation, GSSG, TNF-α, and IL-1β while increasing GSH, SOD, GPx, GR, and mitochondrial quadruple complex enzymes in the hippocampus. TRA inhibited Glial fibrillary acidic protein expression and increased pyruvate dehydrogenase levels. TMZ reduced these changes. TRA decreased the level of JNK and increased Beclin-1 and Bax. TMZ decreased phosphorylated Bcl-2 while increasing the unphosphorylated form in tramadol-treated rats. TMZ activated phosphorylated PI3Ks, Akt, and mTOR proteins. TMZ inhibited tramadol-induced neurotoxicity by modulating the PI3K/Akt/mTOR signaling pathways and its downstream inflammatory, apoptosis, and autophagy-related cascades.

Knockdown of TFRC suppressed the progression of nasopharyngeal carcinoma by downregulating the PI3K/Akt/mTOR pathway

BACKGROUND

The transferrin receptor (TfR) encoded by TFRC gene is the main cellular iron importer. TfR is highly expressed in many cancers and is expected to be a promising new target for cancer therapy; however, its role in nasopharyngeal carcinoma (NPC) remains unknown.

METHODS

The TfR levels were investigated in NPC tissues and cell lines using immunohistochemistry and reverse transcription-quantitative polymerase chain reaction. Knockdown of TFRC using two siRNA to investigate the effects on intracellular iron level and biological functions, including proliferation by CKK-8 assay, colony formation, cell apoptosis and cell cycle by flow cytometry, migration and invasion, and tumor growth in vivo by nude mouse xenografts. RNA sequencing was performed to find possible mechanism after TFRC knockdown on NPC cells and further verified by western blotting.

RESULTS

TfR was overexpressed in NPC cell lines and tissues. Knockdown of TFRC inhibited cell proliferation concomitant with increased apoptosis and cell cycle arrest, and it decreased intracellular iron, colony formation, migration, invasion, and epithelial-mesenchymal transition in HK1-EBV cells. Western blotting showed that TFRC knockdown suppressed the levels of the iron storage protein FTH1, anti-apoptotic marker BCL-xL, and epithelial-mesenchymal transition markers. We confirmed in vivo that TFRC knockdown also inhibited NPC tumor growth and decreased Ki67 expression in tumor tissues of nude mouse xenografts. RNA sequencing and western blotting revealed that TFRC silencing inhibited the PI3K/Akt/mTOR signaling pathway.

CONCLUSIONS

These results indicated that TfR was overexpressed in NPC, and TFRC knockdown inhibited NPC progression by suppressing the PI3K/Akt/mTOR signaling pathway. Thus, TfR may serve as a novel biomarker and therapeutic target for NPC.

Therapeutic potential of Coptis chinensis for arthritis with underlying mechanisms

Arthritis is a common degenerative disease of joints, which has become a public health problem affecting human health, but its pathogenesis is complex and cannot be eradicated. Coptis chinensis (CC) has a variety of active ingredients, is a natural antibacterial and anti-inflammatory drug. In which, berberine is its main effective ingredient, and has good therapeutic effects on rheumatoid arthritis (RA), osteoarthritis (OA), gouty arthritis (GA). RA, OA and GA are the three most common types of arthritis, but the relevant pathogenesis is not clear. Therefore, molecular mechanism and prevention and treatment of arthritis are the key issues to be paid attention to in clinical practice. In general, berberine, palmatine, coptisine, jatrorrhizine, magnoflorine and jatrorrhizine hydrochloride in CC play the role in treating arthritis by regulating Wnt1/β-catenin and PI3K/AKT/mTOR signaling pathways. In this review, active ingredients, targets and mechanism of CC in the treatment of arthritis were expounded, and we have further explained the potential role of AHR, CAV1, CRP, CXCL2, IRF1, SPP1, and IL-17 signaling pathway in the treatment of arthritis, and to provide a new idea for the clinical treatment of arthritis by CC.

A VEGFB-Based Peptidomimetic Inhibits VEGFR2-Mediated PI3K/Akt/mTOR and PLCγ/ERK Signaling and Elicits Apoptotic, Antiangiogenic, and Antitumor Activities

Vascular endothelial growth factor receptor 2 (VEGFR2) mediates VEGFA signaling mainly through the PI3K/AKT/mTOR and PLCγ/ERK1/2 pathways. Here we unveil a peptidomimetic (VGB3) based on the interaction between VEGFB and VEGFR1 that unexpectedly binds and neutralizes VEGFR2. Investigation of the cyclic and linear structures of VGB3 (named C-VGB3 and L-VGB3, respectively) using receptor binding and cell proliferation assays, molecular docking, and evaluation of antiangiogenic and antitumor activities in the 4T1 mouse mammary carcinoma tumor (MCT) model showed that loop formation is essential for peptide functionality. C-VGB3 inhibited proliferation and tubulogenesis of human umbilical vein endothelial cells (HUVECs), accounting for the abrogation of VEGFR2, p-VEGFR2 and, subsequently, PI3K/AKT/mTOR and PLCγ/ERK1/2 pathways. In 4T1 MCT cells, C-VGB3 inhibited cell proliferation, VEGFR2 expression and phosphorylation, the PI3K/AKT/mTOR pathway, FAK/Paxillin, and the epithelial-to-mesenchymal transition cascade. The apoptotic effects of C-VGB3 on HUVE and 4T1 MCT cells were inferred from annexin-PI and TUNEL staining and activation of P53, caspase-3, caspase-7, and PARP1, which mechanistically occurred through the intrinsic pathway mediated by Bcl2 family members, cytochrome c, Apaf-1 and caspase-9, and extrinsic pathway via death receptors and caspase-8. These data indicate that binding regions shared by VEGF family members may be important in developing novel pan-VEGFR inhibitors that are highly relevant in the pathogenesis of angiogenesis-related diseases.

Dexmedetomidine alleviates cerebral ischemia-reperfusion injury via inhibiting autophagy through PI3K/Akt/mTOR pathway

Dexmedetomidine has been shown to protect against cerebral ischemia-reperfusion injury (CIRI). Nevertheless, the precise mechanism is obscure. In order to explore the effect of dexmedetomidine pre-conditioning on autophagy against CIRI in rats, middle cerebral artery occlusion (MCAO) was conducted to establish cerebral ischemia-reperfusion (I/R) model in male SD rats with 2 h ischemia and 24 h reperfusion. Dexmedetomidine was delivered to rats at 10, 50 and 100 µg/kg doses respectively, and LY294002, a PI3K/Akt/mTOR pathway inhibitor, was administered at 10 mg/kg intraperitoneally 30 min before MCAO. Neurological deficit score was assessed and cerebral infarct size was detected by TTC staining. Morris water maze (MWM) was performed to estimate spatial learning and memory ability. Furthermore, to detect activity of PI3K/Akt/mTOR pathway and autophagy, p-Akt, p-mTOR, Beclin-1 and LC3 were measured by western blot. Our findings revealed that 50 and 100 µg/kg of dexmedetomidine pretreatment could improve the neurological deficit score and reduce cerebral infarct size after CIRI, while these effects were markedly suppressed by LY294002. In MWM test, dexmedetomidine was confirmed to shorten escape latency and increase times across platform after CIRI. Nevertheless, LY294002 pretreatment eliminated the improvement of dexmedetomidine on spatial learning and memory ability. Furthermore, dexmedetomidine pretreatment reduced ratios of Beclin-1 and LC3II/LC3I and elevated p-Akt/Akt and p-mTOR/mTOR after CIRI. However, above effects of dexmedetomidine were partly reversed by LY294002. Overall, dexmedetomidine pretreatment exerted neuroprotection against CIRI in rats by attenuating autophagy via the PI3K/Akt/mTOR pathway.

Anti-apoptotic effect of HeidihuangWan in renal tubular epithelial cells via PI3K/Akt/mTOR signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Heidihuang Wan (HDHW) is a classic Chinese herbal formula, which was first recorded in the "Suwen Bingji Qiyi Baoming Collection" written by Liu Wansu during the Jin Dynasty (1115-1234 AD). It is commonly used clinically for the treatment of kidney diseases and its curative effect is stable. Previous animal experiments have confirmed that HDHW can effectively improve renal fibrosis. However, the underlying pharmacological mechanism remains unclear.

AIMS OF THIS STUDY

Renal tubular epithelial cell (RTEC) apoptosis is one of the main pathological features of renal fibrosis. This study aimed to observe the effect and underlying mechanism of HDHW on the apoptosis of RTECs to further explore the pathological mechanism of HDHW against renal fibrosis.

MATERIALS AND METHODS

We examined the HDHW composition in rat serum. In vitro, we first screened out the optimal intervention concentration of HDHW on RTECs using the MTT assay. Hypoxia/reoxygenation was then used to induce apoptosis of RTECs (H/R-RTECs), which were divided into H/R-RTEC, astragaloside IV (positive control), HDHW, and RTECs groups. After 48 h of drug intervention, apoptosis of RTECs was detected using flow cytometry and protein expression was detected by western blotting. The 5/6 nephrectomy rat model was constructed and divided into the normal control, 5/6 nephrectomy, HDHW, and astragaloside IV groups. After 8 weeks of treatment, TUNEL staining was used to detect cell apoptosis, and western blotting was used to detect protein expression.

RESULTS

HDHW downregulated the expression of pro-apoptotic proteins Bax and Caspase3, up-regulated the expression of anti-apoptotic protein Bcl-2, activated the PI3K/Akt/mTOR signaling pathway, and reversed the early apoptosis of RTECs, thereby resisting the apoptosis of RTECs.

CONCLUSION

HDHW inhibits apoptosis of RTECs by modulating the PI3K/Akt/mTOR signaling pathway. This study provides experimental evidence for the anti-fibrotic effect of HDHW on the kidneys and partially elucidates its pharmacological mechanism of action.

Xanthones from Gentianella acuta (Michx.) Hulten Ameliorate Colorectal Carcinoma via the PI3K/Akt/mTOR Signaling Pathway

Colorectal carcinoma (CRC) is a kind of malignant tumor closely related to ulcerative colitis. Xanthone derivatives are one of the most promising therapeutic drugs which have been used in phase I/II clinical trials for cancer therapy. Our previous study indicated that the aerial parts of Gentianella acuta Michx. Hulten (GA) was rich in xanthones and showed a good therapeutic effect on ulcerative colitis in mice, suggesting that GA xanthones might have some therapeutic or ameliorative effects on CRC. However, no relevant study has been reported. This study aims to find the effective substances of GA inhibiting CRC and clarify their mechanism. Solvent extraction, column chromatographic separation, and LC-MS analysis were used to characterize the 70% EtOH extract of GA and track xanthones abundant fraction XF. MTT assay was carried out to clarify the activity of GA fractions; the result showed XF to be the main active fraction. LC-MS analysis was executed to characterize XF, 38 xanthones were identified. Network pharmacology prediction, in vitro activity screening, and molecular docking assay were combined to predict the potential mechanism; the PI3K/Akt/mTOR signaling pathway was found to be most important. Western blot assay on the main active xanthones 1,3,5-trihydroxyxanthone (16), 1,3,5,8-tetrahydroxyxanthone (17), 1,5,8-trihydroxy-3-methoxyxanthone (18), and 1,7-dihydroxy-3,8-dimethoxyxanthone (19) was used to verify the above prediction; these xanthones were found to inhibit the PI3K/Akt/mTOR signaling pathway, and 17 played a significant role among them through Western blot assay using PI3K/AKT/mTOR agonist IGF-1. In conclusion, this study demonstrated that GA xanthones were effective compounds of GA inhibiting CRC by regulating PI3K/Akt/mTOR signaling pathway transduction, at least. Importantly, 1,3,5,8-tetrahydroxyxanthone (17), the most abundant active xanthone in GA, might be a candidate drug for CRC.

Dulaglutide Improves Gliosis and Suppresses Apoptosis/Autophagy Through the PI3K/Akt/mTOR Signaling Pathway in Vascular Dementia Rats

Dulaglutide is a new type of hypoglycemic agent that agonizes glucagon-like peptide-1 receptor (GLP-1RA). It can be concluded from previous studies that a GLP-1RA can reduce apoptosis and regulate autophagy in the nervous system, while related research on dulaglutide in vascular dementia (VD) has not been reported. In our study, the VD rat model was established by bilateral carotid artery occlusion, and the results of the Morris water maze test (MWM) and open-field test showed that the application of dulaglutide could effectively reduce the cognitive decline of VD rats without changing the behavior in the open-field test, which was used to assess an anxiety-like phenotype. We applied HE staining and immunofluorescence labeling to show that dulaglutide treatment significantly alleviated neuronal damage in the hippocampal region of VD rats, and reduced microglial and astrocyte proliferation. Western blot results showed that dulaglutide reduced VD-induced neuronal apoptosis (BCL2/BAX, c-caspase3) and autophagy (P62, LC3B, Beclin-1), and upregulated phosphorylation of PI3K/Akt/mTOR signaling pathway. KEGG pathway analysis of RNA-Sequence results showed that the differentially expressed genes in the dulaglutide treatment group were significantly enriched in the mTOR signaling pathway, and the repressor of mTOR, Deptor, was down-regulated. In conclusion, this study suggested that dulaglutide may alleviate learning and memory impairment and neuron damage in VD rats by attenuating apoptosis, regulating autophagy, and activating the PI3K/Akt/mTOR signaling pathway in neurons, which may make it a promising candidate for the simultaneous treatment of VD and diabetes.

[Electroacupuncture promotes gastrointestinal motility by activating autophagy of Cajal interstitial cells via downregulating PI3K/Akt/mTOR signaling pathway in stomach of diabetic gastro-paresis rats]

OBJECTIVE

To observe the effect of electroacupuncture (EA) of "Zusanli" (ST36), "Sanyinjiao" (SP6) and "Liangmen" (ST21) on gastrointestinal motility, blood glucose content and expression of autophagy-related proteins 1 light chain 3 (LC3), p62, phosphatidyli-nositol-3 kinase (PI3K), protein kinase B (Akt), p-Akt and mammalian target protein of rapamycin (mTOR) of interstitial cells of Cajal (ICCs) in the cultured gastric antrum cells in diabetic gastroparesis (DGP) rats, so as to reveal its mechanisms underlying improvement of DGP.

METHODS

A total of 45 Sprague Dawley (SD) rats were randomly divided into blank control, model, EA, medication (3-methyladenine, 3-MA) and EA+3-MA groups, with 9 rats in each group. The DGP model was established by intraperitoneal injection of 2% streptozotocin (STZ) combined with high-fat and high sugar diet for 8 weeks. The gastric emptying rate was measured by using gavage of phenol red (to measure the propelling length of the phenol red/total length of small intestine ×100%). The symptom score (mental state, coat color and luster, behavior and activity, stool traits) of rats was observed every week and the blood glucose content was measured by using a glucometer. EA (20 Hz/100 Hz, 2 mA) was applied to unilateral ST36, SP6 and ST21 alternatively for 15 min, once daily, 5 days a week for 3 weeks. Rats of the 3-MA and 3-MA+EA groups received intraperitoneal injection of 3-MA (30 mg·kg^-1·d^-1, 10 mg/mL), once daily, 5 days a week for 3 weeks. After 15 days' intervention, the rats were operated for gastric emptying rate test, specimen collection, isolation, and culture of primary ICCs. The expression levels of microtubule associated protein LC3, p62, PI3K, Akt, p-Akt and mTOR of ICCs of cultured gastric antrum cells were detected using Western blot, and the number of autophagosomes in ICC of gastric antrum was observed under transmission electron microscope.

RESULTS

Compared with the blank control group, the symptom score, blood glucose, and the expression levels of p62, class Ⅰ PI3K, Akt, p-Akt and mTOR proteins were increased significantly (P<0.01), while the gastric emptying rate and ratio of LC3Ⅱ/LC3Ⅰ and the expression level of class Ⅲ PI3K protein were significantly decreased (P<0.05, P<0.01) in the model group. In comparison with the model group, the increase of symptom score, blood glucose, and expression levels of p62, class Ⅰ PI3K, Akt, p-Akt and mTOR proteins and the decrease of gastric empty rate and LC3Ⅱ/LC3Ⅰ ratio and the expression level of class Ⅲ PI3K protein were all reversed in both EA and EA+3-MA groups (P<0.05, P<0.01), rather than in the 3-MA group. In addition, 3-MA also reversed modeling-induced increase of class Ⅰ PI3K, Akt, p-Akt and mTOR proteins expression (P<0.01). No significant differences were found between the EA and EA+3-MA in downregulating the levels of symptom score and blood glucose content, and in upregulating gastric empty rate(P>0.05). The effect of EA was notably superior to that of EA+3-MA in upregulating the ratio of LC3Ⅱ/LC3Ⅰ and the expression level of class Ⅲ PI3K protein, and in downregulating the expression of p62, class Ⅰ PI3K, Akt, p-Akt and mTOR proteins (P<0.05, P<0.01). The findings of transmission electron microscopy showed obvious swelling, breakage of some mitochondrial cristae in the ICC cells of antrum and no autophagosomes in the model group and 3-MA group, which was milder in the damage of mitochondrial cristae and marked increase in the autophagosomes in both EA and EA+3-MA groups.

CONCLUSION

EA can improve the gastrointestinal motility and symptoms in DGP rats, which may be related to its functions in downregulating PI3K/Akt/mTOR signaling to promote autophagy level of ICC.

Insulin resistance, autophagy and apoptosis in patients with polycystic ovary syndrome: Association with PI3K signaling pathway

Polycystic ovary syndrome (PCOS) is a disease in which endocrine metabolic abnormalities coexist with reproductive system abnormalities, with the main clinical manifestations including abnormal menstruation, hirsutism, acne, infertility, and obesity, and it is also a high risk for the development of many pregnancy complications, gynecological malignancies and other diseases. Therefore, timely intervention to prevent the progression of PCOS is of great significance for improving the quality of life of most female patients. Insulin resistance (IR) is one of the most common endocrine disorders in PCOS patients, with approximately 75% of PCOS patients experiencing varying degrees of IR. It is now believed that it is mainly related to the PI3K signaling pathway. The role of autophagy and apoptosis of ovarian granulosa cells (GCs) in the pathogenesis of PCOS has also been gradually verified in recent years. Coincidentally, it also seems to be associated with the PI3K signaling pathway. Our aim is to review these relevant studies, to explore the association between the IR, cellular autophagy and apoptosis in PCOS patients and the PI3K pathway. We summarize some of the drug studies that have improved PCOS as well. We have also found that proteomics holds great promise in exploring the pathogenesis of PCOS, and we have published our views on this.

Melatonin Protects against Primary Ovarian Insufficiency by Activating the PI3K/Akt/mTOR Pathway and Inhibiting Autophagy

OBJECTIVE

Primary ovarian insufficiency (POI), which refers to the occurrence of ovarian insufficiency before the age of 40, is indicated by menstrual cycle changes as a precursor and is accompanied by menstrual disorders, elevated gonadotropin levels, and decreased estrogen levels. The incidence of POI is reportedly increasing worldwide and this disease markedly reduces the quality of life and affects the physical and mental health of patients. Treatment options for POI include hormone replacement therapy; however, its efficacy remains unsatisfactory. Therefore, exploring hormonal drugs with superior curative effects and clarifying the molecular mechanism underlying POI pathogenesis could afford new directions for POI therapy.

METHODS

3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assays were used to detect the effects of melatonin (MT) on cell survival and mortality. Flow cytometry was performed to examine the effect of MT on apoptosis. The impact of MT on autophagosome formation was examined using electron microscopy, whereas the expression of autophagy-related proteins and phosphatidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway-related proteins following MT intervention was detected by western blotting.

RESULTS

(1) MT exerted a protective effect on ovarian granulosa cells subjected to serum starvation. (2) MT inhibited serum starvation-induced apoptosis of ovarian granulosa cells. (3) MT inhibited serum starvation-induced autophagosome formation in ovarian granulosa cells. (4) MT inhibited the expression of autophagy-related proteins LC3II/I and Agt5. (5) MT suppressed autophagy in ovarian granulosa cells by activating the PI3K/Akt/mTOR signaling pathway.

CONCLUSION

Collectively, our results demonstrate that MT can inhibit excessive autophagy in ovarian granulosa cells by activating the PI3K/Akt/mTOR pathway, thereby exerting its protective effect against POI.

Neuroprotective mechanism of crocin via PI3K/Akt/mTOR signaling pathway after cerebral infarction: an in vitro study

OBJECTIVES

To explore the potential neuroprotective mechanism of crocin after cerebral infarction.

METHODS

The murine hippocampal neuronal cell line HT-22, was used as the study model, with a control group, OGD-group, low-dose crocin group, middle-dose crocin group, and high-dose crocin group. Except for the control-group, cells in the other groups were treated with OGD for 6 h, in which 1 μg/mL, 2 μg/mL and 5 μg/mL of crocin were added in low-dose group, medium-dose group and high-dose group, respectively. Subsequently, the OGD cells were cultured for another 6 h. CCK-8 assay was carried out to detect the cell viability of each group, flow cytometry was used to detect cell apoptosis, immunofluorescence was conducted to detect the expression of reactive oxygen species, and Western Blot was performed to detect the protein expression of p-PI3K, p-Akt, p-mTOR, LC-3 I, LC-3 II, and Beclin-1.

RESULTS

After hypoxia-reoxygenation treatment, the viability of HT22 cells was remarkably decreased, the apoptosis rate and expression of ROS were significantly increased, the protein expression of p-PI3K, p-Akt and p-mTOR were reduced, while the expression of LC-3 II/I and Beclin-1 were increased. After crocin treatment, the activity of hypoxic reoxygenated cells increased, the apoptosis rate decreased, the expression of reactive oxygen species dropped, the protein expression of p-PI3K, p-Akt and p-mTOR increased, and the expression of LC-3 II/I and Beclin-1 decreased.

CONCLUSION

At the cellular level, crocin can inhibit autophagy by activating the PI3K/Akt/mTOR pathway, and reduce the level of oxidative stress, thus playing a neuroprotective role.

MicroRNA-195-3p promotes hepatic stellate cell activation and liver fibrosis by suppressing PTEN expression

Liver fibrosis is a reversible wound healing reaction characterized by abnormal accumulation of extracellular matrix (ECM) in response to liver injury. Recent studies have shown that it can be epigenetically regulated, especially by microRNAs (miRNAs). It has been acknowledged that activation of hepatic stellate cells (HSCs) is a pivotal step in the initiation and progression of liver fibrosis. Notably, our results showed that miR-195-3p was increased in HSCs isolated from CCl₄-treated mice and that the increase was more pronounced as the degree of liver fibrosis increased. Moreover, treatment of LX-2 cells, a human immortalized hepatic stellate cell line, with TGF-β1 resulted remarkable upregulation of miR-195-3p. Gain-of-function and loss-of-function experiments have suggested that the increased levels of miR-195-3p inhibit the expression of phosphatase and tension homolog deleted on chromosome 10 (PTEN), a negative regulator of the PI3K/Akt/mTOR signaling pathway in liver fibrosis, thereby contributing to HSC activation and proliferation and promoting the expression of profibrotic genes, such as α-SMA and collagen I, in LX-2 cells, which accelerates the accumulation of fibrous extracellular matrix deposition in the liver, while knockdown of miR-195-3p induced the opposite effect. Taken together, these results provide evidence for the harmful role of miR-195-3p in CCl₄-treated mouse liver fibrosis.

Lomerizine 2HCl inhibits cell proliferation and induces protective autophagy in colorectal cancer via the PI3K/Akt/mTOR signaling pathway

Colorectal cancer (CRC) is one of the most common malignancies currently. Despite advances in drug development, the survival and response rates in CRC patients are still poor. In our previous study, a library comprised of 1056 bioactive compounds was used for screening of drugs that could suppress CRC. Lomerizine 2HCl, which is an approved prophylactic drug for migraines, was selected for our studies. The results of in vitro and in vivo assays suggested that lomerizine 2HCl suppresses cell growth and promotes apoptosis in CRC cells. Moreover, lomerizine 2HCl inhibits cell migration and invasion of CRC. RNA sequencing analysis and Western blotting confirmed that lomerizine 2HCl can inhibit cell growth, migration, and invasion through PI3K/AKT/mTOR signaling pathway and induces protective autophagy in CRC. Meanwhile, autophagy inhibition by 3‐methyladenine (3‐MA) increases lomerizine 2HCl‐induced cell apoptosis. Taken together, these results imply that lomerizine 2HCl is a potential anticancer agent, and the combination of lomerizine 2HCl and autophagy inhibitors may serve as a novel strategy to increase the antitumor efficacy of agents in the treatment of CRC.

[Acupuncture improves cognitive function of vascular dementia rats by regulating PI3K/Akt/mTOR pathway]

OBJECTIVE

To explore the mechanism of acupuncture in improving cognitive ability by regulating hippocampal phosphatidylinositol-3 kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway in vascular dementia (VD) rats.

METHODS

A total of 80 male SD rats were randomized into sham operation, model, non-acupoint and acupoint groups (n=18 per group). The VD model was established by ligation of the bilateral common carotid arteries. For rats of the acupoint group, "Baihui" (GV20) and bilateral "Zusanli "(ST36) were needled and stimulated by twirling the needles with reinforcing method, and for rats of the non-acupoint group, the bilateral subcostal spots (about 10 mm superior to the iliac cresta) were needled and stimulated by twirling the needles with uniform reinforcing and reducing method. The treatment was conducted once daily, 6 times a week for two weeks, beginning 3 days after successful modeling. Rats of the sham operation group and model group received grasps as those in the acupoint groups. Morris water maze test was used to detect the abilities of learning and spatial memory. The contents of reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD) and the activities of acetylcholinesterase (AChE) and acetylcholine transferase (ChAT) in the hippocampus tissue were detected by using ELISA, changes of hippocampal mitochondrial membrane potential (MMP) detected using JC-1 fluorescence probe, and the expression levels of hippocampal phosphorylated (p)-PI3K, p-Akt and mTOR proteins measured using Western blot.

RESULTS

Compared with the sham operation group, the escape latency, contents of ROS and MDA, and AChE activity were significantly increased (P<0.05), and the spatial memory ability, SOD activity, ChAT activity, MMP, p-PI3K, p-Akt and mTOR expression levels were significantly decreased in the model group (P<0.05). Compared with the model group, carotid artery ligature-induced increase of the escape latency, contents of ROS and MDA, and AChE activity, and decrease of the spatial memory ability, SOD activity, ChAT activity, MMP, p-PI3K, p-Akt and mTOR expression levels were significantly reversed in the acupuncture group (P< 0.05), but not in the non-acupoint group (P>0.05). The therapeutic effects of acupoint needling were obviously superior to those of non-acupoint needling in decreasing the escape latency, contents of ROS and MDA, and AChE activity (P<0.05), and in increasing the spatial memory ability, SOD activity, ChAT activity, MMP, p-PI3K, p-Akt and mTOR expre-ssion levels (P<0.05).

CONCLUSION

Acupuncture can improve cognitive function of VD rats, which may be related with its functions in easing oxidative stress and MMP reduction by activating PI3K/Akt/mTOR signaling pathway in the hippocampus.

Activated Phosphoinositide 3-Kinase/Akt/Mammalian Target of Rapamycin Signal and Suppressed Autophagy Participate in Protection Offered by Licochalcone A Against Amyloid-β Peptide Fragment 25-35-Induced Injury in SH-SY5Y Cells

OBJECTIVE

To assess effect of licochalcone A (LicA) on amyloid-β (Aβ) peptide fragment 25-35-induced nerve injury and reveal the potential molecular mechanisms involved.

METHODS

Viability of SH-SY5Y cells was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay after treatment with Aβ25-35 and/or LicA, following which apoptosis was detected by flow cytometry and Hoechst staining. Then, reactive oxygen species, glutathione, and superoxide dismutase were measured with flow cytometry and spectrophotometry. The ultrastructure of mitochondria was examined by transmission electron microscopy, and the biomarker proteins of autophagy, apoptosis, and phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway were measured with Western blotting.

RESULTS

LicA improved cell viability and decreased lactate dehydrogenase leakage remarkably in Aβ25-35-induced injury in SH-SY5Y cells. After treatment with LicA, reactive oxygen species, glutathione, and superoxide dismutase levels in cells all were significantly decreased, which indicated that LicA has an antioxidative effect on Aβ25-35-induced oxidative injury. LicA could also significantly reduce Aβ25-35-induced autophagy in SH-SY5Y cells. In the cells injured by Aβ25-35, LicA prevented the transformation from light chain protein 3-I to light chain protein 3-II and reduced the levels of proteins GRP78, GRP94, CHOP, and Bax, but increased the levels of antiapoptotic protein and phosphorylation of PI3K, Akt, and mTOR. These effects of LicA were restored or suppressed by mTOR inhibitor rapamycin or PI3K inhibitor LY294002.

CONCLUSIONS

LicA protects SH-SY5Y cells against Aβ25-35-induced injury, wherein suppressed autophagy and activated PI3K/Akt/mTOR signaling pathway are involved, and mTOR-dependent autophagy at least plays some role.

Insulin-like growth factor 1 promotes neurological functional recovery after spinal cord injury through inhibition of autophagy via the PI3K/Akt/mTOR signaling pathway

Spinal cord injury (SCI) is a serious trauma; however, the mechanisms underlying the role of insulin-like growth factor 1 (IGF-1) in autophagy following SCI remain to be elucidated. The present study aimed to investigate the therapeutic effect of IGF-1 on SCI and to determine whether IGF-1 regulates autophagy via the PI3K/Akt/mTOR signaling pathway. SH-SY5Y neuroblastoma cells were assigned to the H₂O₂, IGF-1 and control groups to investigate subsequent neuron injury in vitro. An MTT assay was performed to evaluate cell survival. In addition, Sprague-Dawley rats were randomly assigned to SCI, SCI + IGF-1 and sham groups, and Basso-Beatlie-Bresnahan scores were assessed to determine rat neurological function. Western blotting was used to analyze the autophagy level and the activation of the PI3K/Akt/mTOR signaling pathway. Cell survival was increased significantly in the IGF-1 group compared with the control group in vitro (P<0.05). Furthermore, neurological function was improved in the SCI + IGF-1 group compared with the control group in vivo (P<0.05). The western blotting results further demonstrated that LC3II/LC3I expression was increased in the IGF-1 group compared with the sham group in vivo and compared with the control group in vitro (both P<0.05). In the SCI + IGF-1 group, the expression levels of PI3K, phosphorylated (p)-Akt and p-mTOR were higher compared with those in the sham and SCI groups in vivo (P<0.05). Moreover, in the IGF-1 group, the expression levels of p-Akt and p-mTOR were higher compared with the control and the H₂O₂ groups in vitro (P<0.05). Collectively, the results of the present study suggested that IGF-1 promoted functional recovery in rats following SCI through neuroprotective effects. Furthermore, the underlying mechanism may involve activation of the PI3K/Akt/mTOR signaling pathway, followed by inhibition of autophagy. However, further investigation into the association between IGF-1-regulated autophagy and the activation of different subtypes of PI3K is required.

Danlou Tablets Inhibit Atherosclerosis in Apolipoprotein E-Deficient Mice by Inducing Macrophage Autophagy: The Role of the PI3K-Akt-mTOR Pathway

Atherosclerosis (AS) is a type of chronic vascular disease, and its etiology is not yet fully understood. AS is characterized by lipid deposition, atherosclerotic plaque formation, vascular stenosis or even complete blockage of the blood vessel wall. Clinical studies have shown that Danlou tablets (DLTs) can improve the heart function, quality of life, and prognosis of patients with coronary heart disease and myocardial infarction. However, its mechanism of action remains unknown. Our study revealed that DLTs ameliorated ApoE^−/−AS mouse aortic atherosclerotic plaques [hematoxylin-eosin (HE) staining and small animal ultrasound] and reduced CD68⁺ macrophage infiltration, the expression of the inflammatory factor interferon-gamma (IFN-γ), vascular smooth muscle α-actin, and serum lipid levels. In vitro, in the macrophage foaming model, DLTs partially restored the activity of RAW264.7 cells, reduced the uptake of lipid droplets, and inhibited lipid droplet accumulation and apoptosis within BMDMs. We also found that Torin1, an autophagy agonist, reduced intracellular lipid deposition in BMDMs, as did DLTs. Moreover, DLTs upregulated the expression of the autophagy-related protein LC3II and decreased p62 accumulation in RAW264.7 cells. DLTs also inhibited the phosphorylation of p-PI3K, p-Akt, and p-mTOR, leading to upregulated autophagy in RAW264.7 cells. In summary, our results suggested that DLTs can promote autophagy in macrophages by inhibiting the PI3K/Akt/mTOR signaling pathway, thereby reducing foam cell formation and improving atherosclerosis.

Baicalin improves podocyte injury in rats with diabetic nephropathy by inhibiting PI3K/Akt/mTOR signaling pathway

Objective

To investigate the effect of baicalin on diabetic nephropathy (DN) rats and podocytes and its mechanism.

Methods

The rat models with DN were established by high-fat and high-sugar diet and intraperitoneal injection of streptozotocin. The fasting blood glucose (FBG) and weight of rats in each group were measured at 0, 1, 2, 3, and 4 weeks. Their biochemical indicators, expression of inflammatory, and antioxidant factors were measured using an automatic biochemical analyzer together with ELISA. Hematoxylin-eosin staining and periodic acid-schiff staining were used to observe the morphological changes in the kidneys of rats in each group. Finally, the expressions of related molecules and PI3K/Akt/mTOR signaling pathway proteins in renal tissues and podocytes were examined by qRT-PCR and Western blot.

Results

Compared with the DN group, the FBG and weight, serum creatinine, blood urea nitrogen, total cholesterol, triacylglycerol, microalbumin, and albumin/creatinine ratio were all significantly decreased in the Baicalin treatment groups in a concentration-dependent manner. The levels of inflammatory factors in kidney tissue and podocytes were decreased. In addition, the activities of lactate dehydrogenase and malondialdehyde in tissue were decreased, while the superoxide dismutase was increased. The pathological sections showed that glomerular atrophy and glomerular basement membrane thickening caused by hyperglycemia were improved in the Baicalin treatment groups. Meanwhile, baicalin inhibited the downregulation of Nephrin and Podocin expressions and upregulation of Desmin expression caused by DN, and inhibited the expressions of p-PI3K, p-Akt, and p-mTOR proteins.

Conclusion

Baicalin slows down podocyte injury caused by DN by inhibiting the activity of PI3K/Akt/mTOR signaling pathway.

[PI3K/Akt/mTOR signal pathway in endocrine disrupting chemicals-induced apoptosis and autophagy of thyroid follicular cells]

Endocrine disrupting chemicals (EDCs) are a kind of exogenous chemicals widely existing in the environment, which cause serious harm to the environment and human health. At present, the impact of this type of substance on the thyroid has attracted much attention.This review summarized the effects of EDCs on thyroid hormones, and phosphatidylinositol 3-kinase (PI3K) /protein kinase B (Akt) /mammalian target of rapamycin (mTOR) (PI3K/Akt/mTOR) signaling pathway and its role in thyroid diseases, and explore the role of PI3K/Akt/mTOR signaling pathway in EDCs-induced apoptosis and autophagy of thyroid follicular epithelial cells.This paper could provide further understandings for thyroid diseases induced by the autophagy and apoptosis of thyroid follicular epithelial cells.

Novel Ferrocene Derivatives Induce Apoptosis through Mitochondria-Dependent and Cell Cycle Arrest via PI3K/Akt/mTOR Signaling Pathway in T Cell Acute Lymphoblastic Leukemia

Simple Summary

T cell acute lymphoblastic leukemia (T-ALL) is a malignant hematologic disease that urgently requires efficient therapeutic agents. The aim of this study is to explore the anti-T-ALL activity of novel ferrocene derivatives. It was found that ferrocene derivatives F1–F7 synthesized by our group inhibited the proliferation of several cancer cell lines in vitro. Among them, F1 and F3 displayed potent cytotoxicity against T-ALL cell lines, especially Jurkat cells, with low cytotoxicity for normal cells. Mechanistically, F1 and F3 could induce apoptosis through mitochondria-dependent pathway mediated by ROS, and cell cycle arrest at G0/G1 phase via the PI3K/Akt/mTOR signaling pathway in Jurkat cells. These results suggested that F1 and F3 could be potential candidates for future T-ALL therapy.

Abstract

T cell acute lymphoblastic leukemia (T-ALL) is one of the most common causes of death in pediatric malignancies. However, the clinical chemotherapy for T-ALL has been limited by numerous side effects, emphasizing that novel anti-T-ALL drugs are urgently needed. Herein, a series of 2-acyl-1-dimethylaminomethyl-ferrocenes for cancer therapy have been evaluated. Among them, F1 and F3 exhibited potent cytotoxicity against T-ALL cell lines, especially Jurkat cells, with low cytotoxicity for normal cells. Further mechanistic studies revealed that F1 and F3 could induce apoptosis in Jurkat cells by destructing mitochondrial membrane, enhancing reactive oxygen species (ROS) generation, decreasing the Bcl-2/Bax ratio, releasing Cytochrome c, and increasing the expression of Cleaved Caspase-9/-3 and Cleaved PARP. Additionally, F1 and F3 could suppress cell proliferation and arrest the cell cycle at G0/G1 phase through the PI3K/Akt/mTOR signaling pathway by down-regulating the expression of CDK6, Cyclin D1, p-Akt, p-GSK-3β, p-mTOR, p-p70 S6K, and up-regulating the expression of P21 and P27, which would also be a possible mechanism. Consequently, ferrocene derivatives F1 and F3 could induce apoptosis through a mitochondria-dependent pathway mediated by ROS, and cell cycle arrest at G0/G1 phase via the PI3K/Akt/mTOR signaling pathway in Jurkat cells. The present study provided fundamental insights into the clinical application of F1 and F3 for the treatment of T-ALL.

Overexpression of sFlt-1 represses ox-LDL-induced injury of HUVECs by activating autophagy via PI3K/AKT/mTOR pathway

Soluble fms-like tyrosine kinase-1 (sFlt-1), a circulating antiangiogenic protein, is involved in the pathogenesis of atherosclerosis (AS), and the underlying mechanism is still unclear. Here, we attempted to investigate the mechanism of action of sFlt-1 in AS. Human umbilical vein endothelial cells (HUVECs) were treated with oxidized low density lipoprotein (ox-LDL) to induce cell injury. ox-LDL treatment increased LC3-II/LC3-I ratio, Beclin-1 expression and GFP-LC3 puncta in HUVECs, suggesting that ox-LDL may induce autophagic flux impairment in HUVECs. ox-LDL-treated HUVECs displayed a decrease of sFlt-1 levels. Moreover, ox-LDL treatment reduced cell proliferation and elevated apoptosis in HUVECs, which was abrogated by sFlt-1 overexpression. Up-regulation of sFlt-1 repressed the activity of PI3K/AKT/mTOR signaling pathway and enhanced autophagy in HUVECs following ox-LDL treatment. Additionally, sFlt-1 overexpression-mediated increase of autophagy in ox-LDL-treated HUVECs was abolished by 3-methyladenine (autophagy inhibitor). 3-methyladenine abrogated the impact of sFlt-1 overexpression on proliferation and apoptosis in ox-LDL-treated HUVECs. This work confirmed that overexpression of sFlt-1 activated autophagy by repressing PI3K/Akt/mTOR signaling pathway, and thus alleviated ox-LDL-induced injury of HUVECs. Therefore, this study suggests that sFlt-1 may be a potential target for AS treatment.

Dendrobium mixture attenuates renal damage in rats with diabetic nephropathy by inhibiting the PI3K/Akt/mTOR pathway

Dendrobium mixture (DMix) is a Traditional Chinese Medicine widely used for preventing and treating diabetic nephropathy (DN). Autophagy contributes to DN development and progression. The present study aimed to investigate the mechanism underlying the protective effects of DMix on the kidneys of rats with DN and to determine whether this involves autophagy. Herein, a high‑sugar and high‑fat diet, combined with the intra‑abdominal injection of low‑dose streptozocin, was used to induce DN in 40 Sprague‑Dawley male rats. In total, 10 additional rats were used as controls. The rats with DN were then randomly divided into three groups and treated with DMix, gliquidone or saline via gastric administration for 8 weeks. Body weight, kidney weight, kidney index, fasting blood glucose (FBG), blood lipid, hemoglobin A1c (HbA1c), insulin, blood urea nitrogen and serum creatinine levels, as well as the 24‑h urinary albumin excretion rate (UAER) were measured. H&E, Periodic Acid‑Schiff and Masson staining were used to examine the renal pathology. The mRNA and protein expression levels of LC3 and Beclin‑1 in renal tissues were measured using reverse transcription‑quantitative PCR and immunohistochemistry, respectively. Western blotting was conducted to measure the protein expression levels of PI3K, phosphorylated (p)‑PI3K, Akt, p‑Akt, mTOR, p‑mTOR, LC3 and Beclin‑1 in renal tissues. It was found that DMix significantly reduced the FBG, blood lipids, HbA1c and insulin levels, kidney weight, kidney index and UAER in rats with DN, as well as improved renal function. Rats with DN showed notable glomerular hypertrophy, an increase in mesangial matrix content and renal interstitial fibrosis. Moreover, DMix notably reduced kidney damage. The results demonstrated that DMix inhibited the phosphorylation of PI3K, Akt and mTOR in the kidney tissues of rats with DN, and increased the protein and mRNA expression levels of LC3 and Beclin‑1. Therefore, it was suggested that DMix has protective effects on the kidney of rats with DN, which may be associated with the inhibition of the PI3K/Akt/mTOR signaling pathway and activation of renal autophagy by this traditional medicine.

8-Gingerol Ameliorates Myocardial Fibrosis by Attenuating Reactive Oxygen Species, Apoptosis, and Autophagy via the PI3K/Akt/mTOR Signaling Pathway

8-gingerol (8-Gin) is the series of phenolic substance that is extracted from ginger. Although many studies have revealed that 8-Gin has multiple pharmacological properties, the possible underlying mechanisms of 8-Gin against myocardial fibrosis (MF) remains unclear. The study examined the exact role and potential mechanisms of 8-Gin against isoproterenol (ISO)-induced MF. Male mice were intraperitoneally injected with 8-Gin (10 and 20 mg/kg/d) and concurrently subcutaneously injected with ISO (10 mg/kg/d) for 2 weeks. Electrocardiography, pathological heart morphology, myocardial enzymes, reactive oxygen species (ROS) generation, degree of apoptosis, and autophagy pathway-related proteins were measured. Our study observed 8-Gin significantly reduced J-point elevation and heart rate. Besides, 8-Gin caused a marked decrease in cardiac weight index and left ventricle weight index, serum levels of creatine kinase and lactate dehydrogenase (CK and LDH, respectively), ROS generation, and attenuated ISO-induced pathological heart damage. Moreover, treatment with 8-Gin resulted in a marked decrease in the levels of collagen types I and III and TGF-β in the heart tissue. Our results showed 8-Gin exposure significantly suppressed ISO-induced autophagosome formation. 8-Gin also could lead to down-regulation of the activities of matrix metalloproteinases-9 (MMP-9), Caspase-9, and Bax protein, up-regulation of the activity of Bcl-2 protein, and alleviation of cardiomyocyte apoptosis. Furthermore, 8-Gin produced an obvious increase in the expressions of the PI3K/Akt/mTOR signaling pathway-related proteins. Our data showed that 8-Gin exerted cardioprotective effects on ISO-induced MF, which possibly occurred in connection with inhibition of ROS generation, apoptosis, and autophagy via modulation of the PI3K/Akt/mTOR signaling pathway.

Effects of miR-202-5p silencing PIK3CA gene expression on proliferation, invasion, and epithelial-mesenchymal transition of cervical cancer SiHa cells through inhibiting PI3K/Akt/mTOR signaling pathway activation

To explore the mechanism of miR-202-5p targeting the expression of PIK3CA and mediating the activation of PI3K/Akt/mTOR signaling pathway on the proliferation, invasion, and epithelial-mesenchymal transition (EMT) of cervical cancer. The objects of study were 105 cases of cervical cancer and their corresponding normal tissues. qRT-PCR was used to detect the expression of miR-202-5p and PIK3CA in adjacent normal tissue and cervical cancer tissue. Dual luciferase reporter assay was used to verify the targeting relationship between miR-202-5p and PIK3CA gene. Human cervical cancer cell lines HPV-16E6, SiHa, HeLa, and CaSki were purchased for our cell experiments. The expression levels of PIK3CA in the cells were detected by qRT-PCR. The cell line with higher expression levels was selected to complete the follow-up experiment. The cultured cells were transfected and divided into the miR-202-5p mimic NC group, miR-202-5p mimic group, miR-202-5p inhibitor NC group, miR-202-5p inhibitor group, siRNA-PIK3CA NC group, siRNA-PIK3CA group, miR-202-5p inhibitor NC + siRNA-PIK3CA NC group, miR-202-5p inhibitor + siRNA-PIK3CA NC group, and miR-202-5p inhibitor + siRNA-PIK3CA group. QRT-PCR was used to detect the expression of miR-202-5p. Western blot and qRT-PCR were applied to detect the mRNA and protein expression levels of related pathway proteins (PIK3CA, PI3K, PTEN, p-Akt1, and p-mTOR) and epithelial-mesenchymal transition-related factors (N-cadherin, E-cadherin, and vimentin). Cell proliferation was detected by plate colony formation assay. Transwell assay was used to detect the invasion ability of each group. When compared with the adjacent tissues, PIK3CA mRNA expression level was significantly increased and miR-202-5p expression level was significantly decreased in cervical cancer tissues (all P < 0.05). PIK3CA was a target gene of miR-202-5p. The mRNA expression level of PIK3CA in SiHa cervical cancer cells was significantly higher than that in CaSki, HeLa, and HPV-16E6 cells (all P < 0.05), and SiHa cervical cancer cells were selected to complete the follow-up experiments. When compared with the corresponding NC group, the expression of miR-202-5p in miR-202-5p mimic group was increased. In addition, the mRNA and protein expression levels of E-cadherin and PTEN in miR-202-5p mimic and siRNA-PIK3CA groups were increased, and the protein expression of p-Akt1 and p-mTOR was decreased, and also, the mRNA and protein expression levels of PIK3CA, PI3K, N-cadherin, and vimentin were decreased (all P < 0.05); in miR-202-5p inhibitor group, the expression levels of miR-202-5p, E-cadherin, and PTEN decreased, the protein expression of p-Akt1 and p-mTOR increased, and the mRNA and protein expression of PIK3CA, PI3K, N-cadherin, and vimentin increased in miR-202-5p inhibitor group (all P < 0.05); in miR-202-5p inhibitor + siRNA-PIK3CA group, the expression of miR-202-5p decreased (P < 0.05), but the mRNA and protein expression of PIK3CA, PI3K, p-Akt1, p-mTOR, N-cadherin, E-cadherin, and vimentin had no significant changes (all P > 0.05). When compared with the corresponding NC group, the number of cell clones in miR-202-5p mimic group and siRNA-PIK3CA group was decreased, and the invasion ability of miR-202-5p inhibitor group was increased, and the invasion ability was enhanced (all P < 0.05); miR-202-5p inhibitor + siRNA-PIK3CA group showed no significant change in the number of cell clones and the rate of invasion (P > 0.05). In conclusion, the overexpression of miR-202-5p can suppress PIK3CA gene expression and the activation of PI3K/Akt/mTOR signaling pathway to suppress the proliferation, invasion, and EMT of cervical cancer.

Silica dust exposure induces pulmonary fibrosis through autophagy signaling

Silicosis is a well-acknowledged occupational lung disease caused by inhalation of a large amount of free silica dust during the production period and eventually a considerable negative impact on the patients' quality of life. Autophagy exerts a critical influence on immune and inflammatory responses during the pathogenesis of pulmonary fibrosis. In this study, we sought to determine whether autophagy is involved in silicosis's pathogenesis and how it may affect pulmonary cellular physiology. In the animal experiments, we found persistent activation of autophagy in the development of pulmonary fibrosis, which was also accompanied by tumor necrosis factor and transforming growth factor expression increased. Therefore, the autophagy signaling pathway may regulate the inflammatory response and affect the progression of fibrosis. Further, in vitro experiments, we used LY294002, RAPA, and N-acetylcysteine (NAC) intervened autophagy. Our results showed that PI3K/Akt/mTOR signaling pathway is involved in the autophagy changed mediated by SiO₂ exposed, and autophagy might play a protective role in the progression of pulmonary fibrosis. Additionally, NAC's effect is not apparent on SiO₂ -mediated autophagy through the PI3K/Akt/mTOR signaling pathway, but it can reduce the inflammatory response on NR8383 cells mediated by SiO2-exposed. Nevertheless, it's interesting that NAC can reduce the inflammatory response on NR8383 cells mediated by SiO₂ -exposed. Taken together, our data demonstrated that SiO₂ -exposed can induce pulmonary fibrosis along with autophagy both in vivo and in vitro, NAC could alleviate the inflammatory response NR8383 cells by SiO₂ -exposed through non PI3K/Akt/mTOR signaling pathway, and the specific mechanism of its action needs further studying.

Effect of BRAF-mediated PI3K/Akt/mTOR pathway on biological characteristics and chemosensitivity of NSCLC A549/DDP cells

The present study aimed to explore the biological characteristics of non-small cell lung cancer (NSCLC) cells and the mechanism of chemosensitivity through the role of the PI3K/Akt/mTOR signaling pathway mediated by BRAF gene silencing. Following cell transfection and grouping, an MTT assay detected the activity of NSCLC cells, a scratch wound test assessed the migration ability, flow cytometry using PI staining detected the cell cycle phase, TUNEL and flow cytometry through Annexin V-PI staining assessed the apoptosis, and colony formation was used to detect the sensitivity of lung cancer cells to cisplatin chemotherapy. Furthermore, the relative expression levels of BRAF, PTEN, PI3K, mTOR mRNA were assessed by RT-qPCR, and the protein expression levels of BRAF, PTEN, PI3K, phosphorylated (p)-PI3K, Akt, p-Akt, mTOR, p-mTOR, cisplatin resistance-related enzymes ERCC1 and BRCA1, apoptotic proteins Bax and Bcl-2 were assessed by western blotting. Compared with the control group and NC group, there were differences in decreased BRAF mRNA expression levels in the small interfering (si)BRAF group and siBRAF + IGF-1 group (both P<0.05). In addition, compared with the control group, the siBRAF, NVP-BEZ235 and siBRAF + NVP-BEZ235 groups had significant decreased cell viability at 2–6 days, decreased migration ability, shortened proportion of S-phase cells, increased proportion of G₁/G₀-phase cells, increased apoptosis rate, decreased number of colony-forming cells, decreased mRNA expression of PI3K, Akt and mTOR, increased PTEN mRNA expression, decreased protein expression levels of PI3K, p-PI3K, Akt, p-Akt, mTOR, p-mTOR, ERCC1, BRCA1 and Bcl-2, and increased protein expression levels of PTEN and Bax (all P<0.05); and more obvious trends were revealed in the siBRAF + NVP-BEZ235 group (all P<0.05); whereas opposite results were detected in the siBRAF + IGF-1 group when compared with the siBRAF group and NVP-BEZ235 group (all P<0.05). Silencing of BRAF gene expression to inhibit the activation of the PI3K/Akt/mTOR signaling pathway exerted a synergistic effect decreasing cell viability, inhibiting the cell cycle and migration, increasing the apoptosis rate, decreasing the number of colony-forming cells and increasing chemosensitivity of NSCLC. Activation of the PI3K/Akt/mTOR signaling pathway may reverse the role of silencing of BRAF gene expression, providing a potential approach for improving the chemosensitivity of NSCLC. The present study for the first time, to the best of our knowledge, clarified the possible mechanism of NSCLC cell biological characteristic changes and chemosensitivity from the perspective of BRAF gene silencing and PI3K/Akt/mTOR signaling pathway activation, providing a potential reference for suppressing tumor aggravation and improving the therapeutic outcomes of NSCLC at the genetic level.

MicroRNA-33a negatively regulates myoblast proliferation by targeting IGF1, follistatin and cyclin D1

MiR-33a is found as a regulator of cell proliferation in many cancer cells. However, it remains unknown if and how miR-33a plays a role in myoblast proliferation. To investigate the effect of miR-33a on myoblast proliferation, miR-33a mimic or inhibitor was co-administered with or without insulin-like growth factor 1 (IGF1) to simulation myoblasts. Our study showed that up-regulation of miR-33a impaired myoblast proliferation, while down-regulation of miR-33a enhanced myoblast proliferation. Mechanistically, we examined that miR-33a can inhibit the transcription of IGF1, follistatin (FST) and cyclin D1 (CCND1) by targeting their 3'UTR region in both HEK293T cells and duck myoblasts. Moreover, up-regulation of miR-33a decreased and its down-regulation increased the mRNA expression of PI3K, Akt, mTOR and S6K. Importantly, the decreased PI3K, Akt, mTOR and S6K expression by miR-33a mimics was abrogated by co-administered with IGF1. Altogether, our results demonstrated that miR-33a may directly target IGF1, FST and CCND1 to inhibit myoblast proliferation via PI3K/Akt/mTOR signaling pathway. In conclusion, miR-33a is a potential negative regulator of myoblast proliferation and by modulating its expression could promote the early development of skeletal muscle.

Catalpol protects rat ovarian granulosa cells against oxidative stress and apoptosis through modulating the PI3K/Akt/mTOR signaling pathway

Disrupted follicular development may result in increased follicular atresia, which is a crucial mechanism of various ovarian pathologies. It has been demonstrated that oxidative stress is associated with disrupted follicular development. Catalpol is a natural compound that has been found to possess antioxidative stress. However, the effects of catalpol on oxidative stress-induced disrupted follicular development remain unclear. In the present study, we evaluated the protective effect of catalpol on hydrogen peroxide (H₂O₂)-induced oxidative damage in granulosa cells (GCs), which play crucial roles in the follicular development. Our results showed that catalpol significantly improved cell viability, reduced reactive oxygen species (ROS) and malondialdehyde (MDA) production, and elevated superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in H₂O₂-induced GCs. Catalpol treatment caused significant increase in bcl-2 expression, and decreases in bax and caspase-9 expressions. Compared with the H₂O₂-induced GCs, caspase-3 activity in catalpol-treated cells was markedly decreased. Furthermore, catalpol caused significant activation of PI3K/Akt/mTOR pathway in GCs in response to H₂O₂ stimulation. Additionally, inhibition of this pathway reversed the inhibitory effects of catalpol on H₂O₂-induced oxidative injury and apoptosis in GCs. In conclusion, these findings suggested that catalpol protected GCs from H₂O₂-induced oxidative injury and apoptosis via activating PI3K/Akt/mTOR signaling pathway. Thus, catalpol might serve as a therapeutic approach for regulating disrupted follicular development.

Ligustrazine induces viability, suppresses apoptosis and autophagy of retinal ganglion cells with ischemia/reperfusion injury through the PI3K/Akt/mTOR signaling pathway

Ligustrazine, an alkaloid monomer extracted from Chuanxiong Rhizoma, has the function of protecting nerve cells. However, the effect and mechanism of ligustrazine on retinal ischemia/reperfusion (I/R) injury still need to be clarified. In our study, retinal ganglion cells (RGC-5) were used to establish a retinal I/R injury model by anaerobic cultivation. Cell viability, autophagy, and apoptosis were evaluated by cell counting kit 8 assay, transmission electron microscopy, and TUNEL staining after treatment with ligustrazine, PI3K inhibitor Ly294002, and/or mTOR inhibitor rapamycin, respectively. Besides, the levels of PI3K/Akt/mTOR pathway and autophagy-related proteins were determined by western blot. Moreover, one-way ANOVA was adopted for inter-group comparisons of measurement data. Our results demonstrated that low-concentration ligustrazine significantly enhanced cell viability and suppressed cell autophagy and apoptosis of RGC-5 cells after I/R injury, suggesting the protective effect of low-concentration ligustrazine on retinal I/R injury. Moreover, the alleviating effect of ligustrazine on RGC-5 with retinal I/R injury was mechanistically associated with the activation of the PI3K/Akt/mTOR pathway. In conclusion, low-concentration ligustrazine has a significant protective effect on RGC-5 cells with retinal I/R injury by activating the PI3K/Akt/mTOR pathway.

High pathogenicity island is associated with enhanced autophagy in pathogenic Escherichia coli HPI - infected macrophages

High pathogenicity island (HPI), which is widely distributed in Escherichia coli (E. coli), can enhance the pathogenicity of E. coli. Thus the HPI positive E. coli could pose a threat to human and animal health. It remains to be elucidated how HPI affects the virulence of pathogenic E. coli. Autophagy is an important mechanism to maintain cellular homeostasis and an innate immunity responses of organisms against pathogens. The interaction between pathogenic E. coli possessing HPI (E. coli HPI) and host autophagy system has not been reported. In this study, it was demonstrated that pathogenic E. coli induced autophagy in 3D4/21 macrophages and HPI was associated with enhanced autophagy through transmission electron microscopy, immunofluorescence and real-time PCR. The PI3K/Akt/mTOR pathway is an important negative regulatory pathway for autophagy. Through detecting the expression of key genes of PI3K/Akt/mTOR pathway, it was speculated that HPI enhanced the inhibition of the signaling pathway stimulated by pathogenic E. coli. Furthermore, HPI inhibited the secretion of IFN-γ, while the presence of HPI did not significantly affect the secretion of IL-1β. This work is the first attempt to explore the interplay between HPI carried by pathogenic E. coli and host cell autophagy. The findings might enable better understanding of the contribution of HPI to pathogenicity.

[Effect of Tongdu Tiaoshen acupuncture on PI3K/Akt/mTOR signaling pathway and autophagy-related proteins of hippocampus in rats with post-stroke depression]

OBJECTIVE

To observe the improvement of Tongdu Tiaoshen acupuncture on depression-like behavior in rats with post-stroke depression (PSD), and to explore its possible mechanism.

METHODS

A total of 48 SD rats were randomized into a sham-operation group, a model group, a Tongdu Tiaoshen group and a non-meridian-non-acupoint group, 12 rats in each group. In the the model group, the Tongdu Tiaoshen group and the non-meridian-non-acupoint group, PSD model was established by the compound method of cerebral medial arterial occlusion, chronic unpredictable mild stress and isolation. Acupuncture was applied at "Dazhui"(GV 14), "Shuigou"(GV 26), "Baihui"(GV 20) and "Shenting" (GV 24) in the Tongdu Tiaoshen group, and at the bilateral dorsum hollows between 3rd and 4th metatarsal bones of the forelegs in the non-meridian-non-acupoint group, needles were retained for 40 min in the both groups, once a day, 6 times a week for 4 weeks. Before model establishment and after intervention, the ethology indice of Zea Longa neurological behavioral score, open-field test and sucrose preference test were evaluated in the 4 groups. The levels of phosphatidylinositol 3-kinase (PI3K), phosphorylated protein kinase B (p-Akt), phosphorylated mammalian target of rapamycin (p-mTOR), Beclin1 and LC3B-Ⅱ/Ⅰin the CA1 region of hippocampus were detected by western blot. The expressions of Beclin1, LC3B-ⅡmRNA in the CA1 region of hippocampus were detected by real-time PCR.

RESULTS

After model established, compared with the sham-operation group, the Zea Longa neurological behavioral scores were increased (P<0.05), the scores of horizontal and vertical motion of the open-field test and the consumption of sucrose solution were decreased in the model group, the Tongdu Tiaoshen group and the non-meridian-non-acupoint group (P<0.05). After intervention, compared with the sham-operation group, the Zea Longa neurological behavioral score, the expression of Beclin1, LC3B-Ⅱ/Ⅰ and LC3B-Ⅱin the CA1 region of hippocampus were increased (P<0.05), the scores of horizontal and vertical motion of the open-field test, the consumption of sucrose solution and the expression of PI3K, p-Akt and p-mTOR were decreased in the model group (P<0.05). After intervention, compared with the model group and the non-meridian-non-acupoint group, the Zea Longa neurological behavioral score, the expression of Beclin1, LC3B-Ⅱ/Ⅰ and LC3B-Ⅱin the CA1 region of hippocampus were decreased (P<0.05), the scores of horizontal and vertical motion of the open-field test, the consumption of sucrose solution and the expression of PI3K, p-Akt and p-mTOR were increased in the Tongdu Tiaoshen group (P<0.05).

CONCLUSION

Tongdu Tiaoshen acupuncture can effectively improve the depression-like behavior in PSD rats, its mechanism may relate to the activation of PI3K/Akt/mTOR signaling pathway and the inhibition of hippocampal neuron autophagy.

[Effect of moxibustion on PI3K/Akt/mTOR signaling pathway in foot-pad synovium in rats with rheumatoid arthritis]

OBJECTIVE

To observe the effect of moxibustion on phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin protein (PI3K/Akt/mTOR) signaling pathway in the foot-pad synovial tissue in rats with rheumatoid arthritis (RA), and to explore the mechanism of moxibustion for treating RA.

METHODS

Forty healthy SD rats were randomly divided into a control group, a model group, a moxibustion group, a cigarette-moxibustion group and a medication group, 8 rats in each group. The RA model was established with subcutaneous injection of complete Freund's adjuvant (CFA) in the left hind foot-pad under wind, cold and wet environment in the model group, the moxibustion group, the cigarette-moxibustion group and the medication group. The rats in the moxibustion group were treated with moxibustion at "Zusanli" (ST 36) for 20 min; the rats in the cigarette-moxibustion group were treated with moxibustion of ordinary cigarette at "Zusanli" (ST 36) for 20 min; the rats in the medication group were treated with tripterygium glycosides suspension (0.8 mg/100 g) by gavage. All the intervention was given once a day for 15 days. The left hind foot-pad volume was measured before and after modeling and after 15-day intervention. After 15-day intervention, the serum levels of IL-17 and IL-23 were detected by ELISA method, and the expression levels of PI3K, Akt and mTOR in synovial tissue of left hind foot-pad were detected by Western blot method.

RESULTS

The volume of left hind foot-pad, the serum levels of IL-23 and IL-17 and the expression of PI3K, Akt and mTOR in synovial tissue of left hind foot-pad in the model group were higher than those in the control group (P<0.01). After intervention, the volume of left hind foot-pad and the expression of PI3K, Akt and mTOR protein in synovium tissue in the moxibustion group and medication group were lower than those in the model group (P<0.01, P<0.05), while the serum levels of IL-17 and IL-23 in the moxibustion group were lower than those in the model group (P<0.01). The volume of left hind foot-pad, the serum levels of IL-23 and the expression of mTOR protein in synovial tissue in the moxibustion group were lower than those in the medication group (P<0.01, P<0.05), while the volume of left hind foot-pad, the serum levels of IL-23 and the expression of PI3K, Akt and mTOR protein in synovium tissue in the moxibustion group were lower than those in the cigarette-moxibustion group (P<0.01).

CONCLUSION

Moxibustion may play a therapeutic effect on RA by inhibiting the level of IL-23, IL-17 and the activity PI3K/Akt/mTOR, and regulating inflammatory response and autophagy.

Everolimus reduces postoperative arthrofibrosis in rabbits by inducing autophagy-mediated fibroblast apoptosis by PI3K/Akt/mTOR signaling pathway

OBJECTIVE

To investigate the effects of everolimus (EVE) on postoperative fibrosis in the knee joint and the potentially relevant signaling pathways.

METHODS

CCK-8 and flow cytometry assays were used to detect the effect of EVE on human fibroblast viability and apoptosis induction. IF and TEM were used to assess fibroblast autophagy. 3-methyladenine (3-MA) was applied to inhibit autophagy to clarify the relationship between autophagy and apoptosis. WB was used to measure the expression of proteins related to apoptosis, autophagy and the mTOR signaling pathway. A rabbit model of knee joint fibrosis was established and topically treated with various concentrations of EVE. IF-P was applied to identify that the main components cells of the fibrotic tissue and histomorphological staining was used to detect the degree of fibrosis and the content of collagen.

RESULTS

Histomorphological staining demonstrated that EVE could reduce the degree of postoperative fibrosis and collagen deposition in the knee joint. The results of IF, TEM, flow cytometry assays and WB detection showed that EVE could activate autophagy and induce fibroblasts apoptosis. Meanwhile, the expression levels of p-PI3K, p-Akt, p-mTOR were downregulated with EVE treatment. After the inhibition of autophagy by 3-MA treatment, the increased fibroblasts apoptosis by EVE treatment was partially decreased.

CONCLUSION

Everolimus can reduce surgery-induced knee fibrosis by inducing autophagy-mediated fibroblast apoptosis, which may be involved with the regulation of the PI3K/Akt/mTOR signaling pathway.

α-Cyperone inhibits the proliferation of human cervical cancer HeLa cells via ROS-mediated PI3K/Akt/mTOR signaling pathway

Cervical cancer is the fourth leading killer of female cancer patients worldwide. Each year more than half a million women are diagnosed with cervical cancer and the disease results in over 300, 000 deaths. α-Cyperone is known as the principal active ingredient in the Cyperus rotundus (Family: Cyperaceae). However, the effects of α-Cyperone on cancers, especially on cervical cancer, are yet to be explored. In the present study, the underlying mechanism of the anti-tumor activity of α-Cyperone against HeLa cells was investigated. The results showed that α-Cyperone inhibited proliferation and induced apoptosis in HeLa cells. Mechanistically, α-Cyperone promoted HeLa cells apoptosis via a mitochondrial apoptotic pathway, which was proved by increased level of intracellular reactive oxygen species (ROS) and upregulated expression of cytochrome c, cleaved caspase-3, PARP, and Bax. Further RNA-sequencing revealed α-Cyperone inhibited the activation of PI3K/Akt/mTOR signaling pathway in HeLa cells, which confirmed by PI3K inhibitor and agonist. The PI3K inhibitor (LY294002) synergized with α-Cyperone in arresting the growth of HeLa cells, whereas the PI3K agonist (IGF-1) abrogated such an effect. Interestingly, the expression of PD-L1 was attenuated by both α-Cyperone and LY294002, while the supplement of IGF-1 rescued the low expression of PD-L1. In conclusion, our results reveal that the inhibitory effect of α-Cyperone on HeLa cell growth is triggered via the ROS-mediated PI3K/Akt/mTOR signaling pathway and closely related to a decline in the PD-L1 expression.

The overexpression of miRNA-212-5p inhibited the malignant proliferation of liver cancer cells HepG2 and the tumor formation in nude mice with transplanted tumor through down-regulating SOCS5

BACKGROUND

This study aims to investigate the effect of miR-212-5p overexpression targeting suppressor of cytokine signaling 5 (SOCS5) on the malignant proliferation of liver cancer cells HepG2 and tumor formation in nude mice with transplanted tumors.

METHODS

Luciferase reporter assay was used to detect the targeted relationship between miR-212-5p and SOCS5, and SOCS5 was overexpressed by the SOCS5 pcDNA vector. MiR-212-5p mimic and pc DNA-SOCS5 were transfected into liver cancer HepG2 cells alone or in combination, and the cells were randomly divided into four groups, the control group, mimic group, SOCS5 group and mimic + SOCS5 group for subsequent experiments. The orthotopic xenograft mouse models were established by using HepG2 cells in BALB/c athymic nude mice.

RESULTS

The results showed that there was a direct targeting relationship between miR-212-5p and SOCS5. Compared with the control group, the clone formation rate, the levels of Ki67, and proliferating cell nuclear antigen (PCNA) protein in the mimic group were significantly lower (P<0.05), but the apoptosis rate was significantly higher (P<0.05). The ratio of Bax/Bcl-2, cleaved Caspase-3/Caspase-3, and cleaved Caspase-9/Caspase-9 was significantly higher (P<0.05), while the ratios of p-phosphatidylinositol 3 kinase (PI3K)/PI3K, p- Protein kinase B (AKT)/AKT, and p-mammalian target of rapamycin (mTOR)/mTOR were significantly reduced (P<0.05). In the SOCS5 group, the result was reversed. Interesting, In the mimic+SOCS5 group the clone formation rate, the protein levels of Ki67, and PCNA were significantly decreased (P<0.05) while the apoptosis rate was significantly increased (P<0.05). The ratio of Bax/Bcl-2, cleaved Caspase-3/Caspase-3, and cleaved Caspase-9/Caspase-9 was significantly increased (P<0.05). The ratios of p-PI3K/PI3K, p-Akt/AKT, and p-mTOR/mTOR were significantly reduced (P<0.05). In vivo, The level of miR-212-5p was significantly increased, with SOCS5 decreased (P<0.05). Furthermore, the number of Ki67 positive cells was significantly reduced (P<0.05), and the apoptosis rate increased significantly (P<0.05). Additionally, the ratio of p-PI3K/PI3K, P-AKT/AKT, P-mTOR/mTOR decreased significantly (P<0.05).

CONCLUSIONS

miR-212-5p overexpression down-regulated SOCS5 could inhibit the malignant proliferation of HCC cells HepG2 and tumor formation in nude mice with transplanted tumors.