A tellurium-based small compound ameliorates tumor metastasis by downregulating heparanase expression.

Tellurium is a rare element, and ammonium trichloro (dioxoethylene-o,o') tellurate (AS101) is the most bioactive molecule among several synthetic tellurium compounds. AS101 was found to be immunomodulatory and can modulate types of cytokines. However, the effect of AS101 on tumor metastasis remains unclear. Heparanase, an endo-glucuronidase, cleaves heparin sulfate side chains of proteoglycans on the cell surface, further leading to the degradation of the extracellular matrix. Heparanase also releases angiogenic factors in the extracellular matrix, is overexpressed in tumor cells, and promotes tumor metastasis and angiogenesis. In this study, we investigated the effect of AS101 in 4T1 and CT26 cells, especially heparanase. Heparanase expression was downregulated in 4T1 and CT26 cells after treatment with AS101 in vitro. The protein level involved in the protein kinase-B/mammalian target of rapamycin (AKT/mTOR) signaling pathway also declined. Cell migration assays revealed the inhibitory effect of AS101 on migration. The results of this study indicate that AS101 inhibits tumor migration by downregulating heparanase through the AKT/mTOR signaling pathway and has positive effects in vivo.

Glucose fluctuations aggravate cardiomyocyte apoptosis by enhancing the interaction between Txnip and Akt.

BACKGROUND: Glucose fluctuations may be involved in the pathophysiological process of cardiomyocyte apoptosis, but the exact mechanism remains elusive. This study focused on exploring the mechanisms related to glucose fluctuation-induced cardiomyocyte apoptosis. METHODS: Diabetic rats established via an injection of streptozotocin were randomized to five groups: the controlled diabetic (CD) group, the uncontrolled diabetic (UD) group, the glucose fluctuated diabetic (GFD) group, the GFD group rats with the injection of 0.9% sodium chloride (NaCl) (GFD + NaCl) and the GFD group rats with the injection of N-acetyl-L-cysteine (NAC) (GFD + NAC). Twelve weeks later, cardiac function and apoptosis related protein expressions were tested. Proteomic analysis was performed to further analyze the differential protein expression pattern of CD and GFD. RESULTS: The left ventricular ejection fraction levels and fractional shortening levels were decreased in the GFD group, compared with those in the CD and UD groups. Positive cells tested by DAB-TUNEL were increased in the GFD group, compared with those in the CD group. The expression of Bcl-2 was decreased, but the expressions of Bax, cleaved caspase-3 and cleaved caspase-9 were increased in response to glucose fluctuations. Compared with CD, there were 527 upregulated and 152 downregulated proteins in GFD group. Txnip was one of the differentially expressed proteins related to oxidative stress response. The Txnip expression was increased in the GFD group, while the Akt phosphorylation level was decreased. The interaction between Txnip and Akt was enhanced when blood glucose fluctuated. Moreover, the application of NAC partially reversed glucose fluctuations-induced cardiomyocyte apoptosis. CONCLUSIONS: Glucose fluctuations lead to cardiomyocyte apoptosis by up-regulating Txnip expression and enhancing Txnip-Akt interaction.

FDA-approved antivirals ledipasvir and daclatasvir downregulate the Src-EPHA2-Akt oncogenic pathway in colorectal and triple-negative breast cancer cells.

Direct-acting antivirals ledipasvir (LDV) and daclatasvir (DCV) are widely used as part of combination therapies to treat Hepatitis C infections. Here we show that these compounds inhibit the proliferation, invasion, and colony formation of triple-negative MDA-MB-231 breast cancer cells, SRC-transduced SW620 colon cancer cells and SRC- transduced NIH3T3 fibroblasts. DCV also inhibits the expression of PDL-1, which is responsible for resistance to immunotherapy in breast cancer cells. The demonstrated low toxicity in many Hepatitis C patients suggests LDV and DCV could be used in combination therapies for cancer patients. At the molecular level, these direct-acting antivirals inhibit the phosphorylation of Akt and the ephrin type A receptor 2 (EPHA2) by destabilizing a Src-EPHA2 complex, although they do not affect the general kinase activity of Src. Thus, LDV and DCV could be effective drugs for Src-associated cancers without the inherent toxicity of classical Src inhibitors.

Revealing Dynamics of Protein Phosphorylation: A Study on the Cashmere Fineness Disparities in Liaoning Cashmere Goats.

Exploring the landscape of protein phosphorylation, this investigation focuses on skin samples from LCG (Liaoning Cashmere Goats), characterized by different levels of cashmere fineness. Employing LC-MS/MS technology, we meticulously scrutinized FT-LCG (fine-type Liaoning Cashmere Goats) and CT-LCG (coarse-type Liaoning Cashmere Goats). Identifying 512 modified proteins, encompassing 1368 phosphorylated peptide segments and 1376 quantifiable phosphorylation sites, our exploration further revealed consistent phosphorylation sites in both groups. Analysis of phosphorylated peptides unveiled kinase substrates, prominently featuring Protein Kinase C, Protein Kinase B and MAPK3-MAPK1-MAPK7-NLK-group. Differential analysis spotlighted 28 disparate proteins, comprising six upregulated and twenty-two downregulated. Cluster analysis showcased the robust clustering efficacy of the two sample groups. GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analyses underscored the significance of the purine metabolism pathway, suggesting its pivotal role in modulating cashmere fineness in LCG. Notably, through differential protein analysis, two crucial proteins were identified: HSL-X (hormone-sensitive lipase isoform X1) and KPRP (keratinocyte proline-rich protein). Further evidence supports LIPE and KPRP as key genes regulating cashmere fineness, paving the way for promising avenues in further research. These findings not only contribute to a nuanced understanding of protein-level dynamics in cashmere but also provide a theoretical foundation for the selective breeding of superior Liaoning Cashmere Goat strands.

Octanol alleviates chronic constriction injury of sciatic nerve-induced peripheral neuropathy by regulating AKT/mTOR signaling.

OBJECTIVE: Activation of gap junction channels can induce neuropathic pain. Octanol can limit the conductance of gap junctions containing connexin 43 proteins. Thus, this study focused on the roles of octanol in chronic constriction injury (CCI)-induced peripheral neuropathy in mice and its mechanisms of action. METHODS: Male mice were assigned into control, sham, CCI, CCI + Octanol-20 mg/kg, CCI + Octanol-40 mg/kg and CCI + Octanol-80 mg/kg groups. CCI was performed by applying three loose ligations to mouse sciatic nerve, and the mice with CCI was administered with 20 mg/kg, 40 mg/kg, or 80 mg/kg octanol. The neuropathic pain development was examined by assessing thermal withdrawal latency, paw withdrawal mechanical threshold, and sciatic functional index. Histopathological changes were evaluated by hematoxylin and eosin staining. The phosphorylation of protein kinase B (Akt) and mammalian target of rapamycin (mTOR) was examined by western blotting. The expression of Akt and mTOR was also evaluated by immunofluorescence staining. RESULTS: Octanol alleviated the CCI-induced mechanical and thermal hyperalgesia and sciatic functional loss. Additionally, octanol relieved the CCI-induced abnormal histopathological changes. Mechanistically, octanol inactivated the Akt/mTOR pathway in the mice with CCI. CONCLUSION: In conclusion, octanol can alleviate CCI-induced peripheral neuropathic by regulating the Akt/mTOR pathway and might be a novel pharmacological intervention for neuropathic pain.

[Effect of Sakuranetin on Microglia-Mediated Neuroinflammation After Spinal Cord Injury].

Objective To investigate the effects of sakuranetin (SK) on motor functions in the mouse model of spinal cord injury (SCI) and decipher the mechanism.Methods Fifty-four C57BL/6J mice were randomized into sham,SCI,and SK groups.The mice in the sham group underwent only laminectomy at T9,while those in the SCI and SK groups were subjected to spinal cord contusion injury at T9.Behavioral tests were conducted at different time points after surgery to evaluate the motor functions of mice in each group.The pathological changes in the tissue were observed to assess the extent of SCI in each group.The role and mechanism of SK in SCI were predicted by gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analyses.Reverse transcription real-time fluorescence quantitative PCR,ELISA,and immunofluorescence were employed to evaluate the inflammation and activation of microglia in SCI mice.BV2 cells in vitro were classified into control (Con),lipopolysaccharide (LPS),and LPS+SK groups.The effects of SK intervention on the release of inflammatory cytokines and the activation of BV2 cells were evaluated.Furthermore,the phosphatidylinositol-3-kinase(PI3K)/protein kinase B (AKT) signaling pathway activator insulin-like growth factor-1 (IGF-1) was used to treat the SK-induced BV2 cells in vitro (SK+IGF-1 group),and SK was used to treat the IGF-1-induced BV2 cells in vitro (IGF-1+SK group).Western blotting was conducted for molecular mechanism validation.Results Behavioral tests and histological staining results showed that compared with the SCI group,the SK group exhibited improved motor abilities and reduced area of damage in the spinal cord tissue (all P<0.001).The GO enrichment analysis predicted that SK may be involved in the inflammation following SCI.The KEGG enrichment analysis predicted that SK regulated the PI3K/Akt pathway to exert the neuroprotective effect.The results from in vitro and in vivo experiments showed that SK lowered the levels of tumor necrosis factor-α,interleukin-6,and interleukin-1ß and inhibited the activation of microglia (all P<0.05).The results of Western blotting showed that SK down-regulated the phosphorylation levels of PI3K and Akt (all P<0.001) and inhibited the IGF-1-induced elevation of PI3K and Akt phosphorylation levels (all P<0.001).Conversely,IGF-1 had the opposite effects (P=0.001,P<0.001).The results of reverse transcription real-time fluorescence quantitative PCR,ELISA,and immunofluorescence showed that the SK+IGF-1 group had higher levels of inflammatory cytokines and more activated microglia than the SK group(all P<0.05).Conclusion SK may suppress the activation of the PI3K/Akt pathway to inhibit the inflammation mediated by SCI-induced activation of microglia,ameliorate the pathological damage of the spinal cord tissue,and promote the recovery of motor functions in SCI mice.

Fibroblast growth factor 2 enhances BMSC stemness through ITGA2-dependent PI3K/AKT pathway activation.

Bone marrow-derived mesenchymal stem cells (BMSC) are promising cellular reservoirs for treating degenerative diseases, tissue injuries, and immune system disorders. However, the stemness of BMSCs tends to decrease during in vitro cultivation, thereby restricting their efficacy in clinical applications. Consequently, investigating strategies that bolster the preservation of BMSC stemness and maximize therapeutic potential is necessary. Transcriptomic and single-cell sequencing methodologies were used to perform a comprehensive examination of BMSCs with the objective of substantiating the pivotal involvement of fibroblast growth factor 2 (FGF2) and integrin alpha 2 (ITGA2) in stemness regulation. To investigate the impact of these genes on the BMSC stemness in vitro, experimental approaches involving loss and gain of function were implemented. These approaches encompassed the modulation of FGF2 and ITGA2 expression levels via small interfering RNA and overexpression plasmids. Furthermore, we examined their influence on the proliferation and differentiation capacities of BMSCs, along with the expression of stemness markers, including octamer-binding transcription factor 4, Nanog homeobox, and sex determining region Y-box 2. Transcriptomic analyzes successfully identified FGF2 and ITGA2 as pivotal genes responsible for regulating the stemness of BMSCs. Subsequent single-cell sequencing revealed that elevated FGF2 and ITGA2 expression levels within specific stem cell subpopulations are closely associated with stemness maintenance. Moreover, additional in vitro experiments have convincingly demonstrated that FGF2 effectively enhances the BMSC stemness by upregulating ITGA2 expression, a process mediated by the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway. This conclusion was supported by the observed upregulation of stemness markers following the induction of FGF2 and ITGA2. Moreover, administration of the BEZ235 pathway inhibitor resulted in the repression of stemness transcription factors, suggesting the substantial involvement of the PI3K/AKT pathway in stemness preservation facilitated by FGF2 and ITGA2. This study elucidates the involvement of FGF2 in augmenting BMSC stemness by modulating ITGA2 and activating the PI3K/AKT pathway. These findings offer valuable contributions to stem cell biology and emphasize the potential of manipulating FGF2 and ITGA2 to optimize BMSCs for therapeutic purposes.

Autocrine IL-8 Contributes to Propionibacterium Acnes-induced Proliferation and Differentiation of HaCaT Cells via AKT/FOXO1/ Autophagy.

OBJECTIVE: Proprionibacterium acnes (P. acnes)-induced inflammatory responses, proliferation and differentiation of keratinocytes contribute to the progression of acne vulgaris (AV). P. acnes was found to enhance the production of interleukin-8 (IL-8) by keratinocytes. This study aimed to investigate the role of IL-8 in P. acnes-induced proliferation and differentiation of keratinocytes and the underlying mechanism. METHODS: The P. acnes-stimulated HaCaT cell (a human keratinocyte cell line) model was established. Western blotting and immunofluorescence were performed to detect the expression of the IL-8 receptors C-X-C motif chemokine receptor 1 (CXCR1) and C-X-C motif chemokine receptor 2 (CXCR2) on HaCaT cells. Cell counting kit-8 (CCK-8) assay, 5-ethynyl-20-deoxyuridine (EdU) assay and Western blotting were performed to examine the effects of IL-8/CXCR2 axis on the proliferation and differentiation of HaCaT cells treated with P. acnes, the IL-8 neutralizing antibody, the CXCR2 antagonist (SB225002), or the CXCR1/CXCR2 antagonist (G31P). Western blotting, nuclear and cytoplasmic separation, CCK-8 assay, and EdU assay were employed to determine the downstream pathway of CXCR2 after P. acnes-stimulated HaCaT cells were treated with the CXCR2 antagonist, the protein kinase B (AKT) antagonist (AZD5363), or the constitutively active forkhead box O1 (FOXO1) mutant. Finally, autophagy markers were measured in HaCaT cells following the transfection of the FOXO1 mutant or treatment with the autophagy inhibitor 3-methyladenine (3-MA). RESULTS: The expression levels of CXCR1 and CXCR2 were significantly increased on the membrane of HaCaT cells following P. acnes stimulation. The IL-8/CXCR2 axis predominantly promoted the proliferation and differentiation of P. acnes-induced HaCaT cells by activating AKT/FOXO1/autophagy signaling. In brief, IL-8 bound to its receptor CXCR2 on the membrane of keratinocytes to activate the AKT/FOXO1 axis. Subsequently, phosphorylated FOXO1 facilitated autophagy to promote the proliferation and differentiation of P. acnes-induced keratinocytes. CONCLUSION: This study demonstrated the novel autocrine effect of IL-8 on the proliferation and differentiation of P. acnes-induced keratinocytes, suggesting a potential therapeutic target for AV.

Effect and mechanism of Jinkui Shenqi Pill on preventing neural tube defects in mice based on network pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE: jinkui Shenqi Pill (JSP) is a classic traditional Chinese medicine used to treat "Kidney Yang Deficiency" disease. Previous studies indicate a protective effect of JSP on apoptosis in mouse neurons. AIM OF THE STUDY: This research, combining network pharmacology with in vivo experiments, explores the mechanism of JSP in preventing neural tube defects (NTDs) in mice. MATERIALS AND METHODS: Network pharmacology analyzed JSP components and targets, identifying common genes with NTDs and exploring potential pathways. Molecular docking assessed interactions between key JSP components and pathway proteins. In an all-trans retinoic acid (atRA)-induced NTDs mouse model, histopathological changes were observed using HE staining, neuronal apoptosis was detected using TUNEL, and Western Blot assessed changes in the PI3K/AKT signaling pathway and apoptosis-related proteins. RESULTS: Different concentrations of JSP led to varying degrees of reduction in the occurrence of neural tube defects in mouse embryos, with the highest dose showing the most significant decrease. Furthermore, it showed a better reduction in NTDs rates compared to folic acid (FA). Network pharmacology constructed a Drug-Active Ingredient-Gene Target network, suggesting key active ingredients such as Quercetin, Wogonin, Beta-Sitosterol, Kaempferol, and Stigmasterol, possibly acting on the PI3K/Akt signaling pathway. Molecular docking confirmed stable binding structures. Western Blot analysis demonstrated increased expression of p-PI3K, p-Akt, p-Akt1, p-Akt2, p-Akt3, downregulation of cleaved caspase-3 and Bax, and upregulation of Bcl-2, indicating prevention of NTDs through anti-apoptotic effects. CONCLUSION: We have identified an effective dosage of JSP for preventing NTDs, revealing its potential by activating the PI3K/Akt signaling pathway and inhibiting cell apoptosis in atRA-induced mouse embryonic NTDs.

Overview of carboxyl­terminal modulator protein 1 and its importance in various metabolic regulations (Review).

Acyl­coenzyme A thioesterases (ACOTs) are crucial in mediating lipid metabolic functions, including energy expenditure, hepatic gluconeogenesis and neuronal function. The two distinct types are type I and II ACOTs, the latter of which are 'hotdog' fold superfamily members. Type II ACOTs include carboxyl­terminal modulator protein 1 (CTMP1), also termed thioesterase superfamily member 4 (THEM4), and CTMP2, also termed THEM5. Due to their similar structural features and distinct sequence homology, CTMP1 and CTMP2 stand out from other type II ACOTs. CTMP1 was initially known as a protein kinase B (PKB) inhibitor that attenuates PKB phosphorylation. PKB is the central regulator of various cellular functions, including survival, proliferation, growth and metabolism. Therefore, by inhibiting PKB, CTMP1 can affect various cellular processes. Various other functions of CTMP1 have been revealed, including functions in cancer, brain injury, mitochondrial function and lipid metabolism. CTMP2 is a paralog of CTMP1 and was first identified as a cardiolipin remodeling factor involved in the development of fatty liver. As the functions of CTMP1 and CTMP2 were discovered separately, a review to summarize and connect these findings is essential. The current review delineates the intricate complexity of CTMP regulation across different metabolic pathways and encapsulates the principal discoveries concerning CTMP until the present day.

Roles of THEM4 in the Akt pathway: a double-edged sword. / THEM4在Akt通路中的作用：一把双刃剑.

The protein kinase B (Akt) pathway can regulate the growth, proliferation, and metabolism of tumor cells and stem cells through the activation of multiple downstream target genes, thus affecting the development and treatment of a range of diseases. Thioesterase superfamily member 4 (THEM4), a member of the thioesterase superfamily, is one of the Akt kinase-binding proteins. Some studies on the mechanism of cancers and other diseases have shown that THEM4 binds to Akt to regulate its phosphorylation. Initially, THEM4 was considered an endogenous inhibitor of Akt, which can inhibit the phosphorylation of Akt in diseases such as lung cancer, pancreatic cancer, and liver cancer, but subsequently, THEM4 was shown to promote the proliferation of tumor cells by positively regulating Akt activity in breast cancer and nasopharyngeal carcinoma, which contradicts previous findings. Considering these two distinct views, this review summarizes the important roles of THEM4 in the Akt pathway, focusing on THEM4 as an Akt-binding protein and its regulatory relationship with Akt phosphorylation in various diseases, especially cancer. This work provides a better understanding of the roles of THEM4 combined with Akt in the treatment of diseases.

Protective Effect and Related Mechanism of Modified Danggui Buxue Decoction on Retinal Oxidative Damage in Mice based on Network Pharmacology.

INTRODUCTION: Age-related macular degeneration (AMD) is one of the common diseases that cause vision loss in the elderly, and oxidative stress has been considered a major pathogenic factor for AMD. Modified Danggui Buxue Decoction (RRP) has a good therapeutic effect on non-proliferatic diabetic retinopathy and can improve the clinical symptoms of patients. AIM: This study aimed to predict and verify the protective effect and mechanism of RRP on retinal oxidative damage in mice based on network pharmacology and animal experiments. METHODS: A total of 15 key active components included in RRP interacted with 57 core targets related to retinal oxidative damage (such as AKT1, NFE2L2, HMOX1), mainly involved in the AGE-RAGE signaling pathway in diabetic complications, PI3K-AKT signaling pathway and so on. Further studies in vivo found that RRP improved the retinal oxidative damage, increased the content of SOD and GSH, decreased the content of MDA in mouse serum, promoted the expression of p-PI3K, p-AKT, Nrf2, HO-1 and NQO1 proteins in the mouse retina, and inhibited the expression of Nrf2 in the cytoplasm. RESULTS: This study revealed that RRP had a protective effect on oxidative damage of the retina in mice, and might exert anti-oxidative effect by activating the PI3K/Akt/Nrf2 signal pathway. CONCLUSION: This study provided scientific data for the further development of hospital preparations of RRP, and a good theoretical basis for the clinical application of RRP.

Effect of the Protein Kinase B (PKB) Gene on the Carcinogenesis of Oral Squamous Cell Carcinoma in the South Indian Population.

INTRODUCTION: The most common head and neck cancer is oral squamous cell carcinoma (OSCC). It is also one of the most prevalent forms of cancer globally. The current pharmacological treatment strategy for oral cancer lacks specificity and is capable of causing various side effects. This fact highlights the increasing need for targeted therapy. Interestingly, protein kinase B (PKB), commonly referred to as the AKT serine/threonine kinase, is an oncogenic protein that controls cell development, proliferation, apoptosis, and glycogen metabolism. Thus, the present study analyzed the AKT gene expression in OSCC patient samples. MATERIALS AND METHODS: A total of 25 OSCC tissue samples and normal tissue samples were collected from the patients who reported to the Department of Oral and Maxillofacial Surgery, Saveetha Dental College and Hospitals in Chennai, India. The tissues were processed for H&E staining for histopathological confirmation, and expression studies of the AKT gene were done on both healthy and proven OSCC tissue samples. The data were shown as mean ± standard deviation, and p<0.05* was considered to be statistically significant. RESULTS: The quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis revealed that the AKT gene had been significantly upregulated in the OSCC tissue samples when compared to normal tissues (p<0.05). Moreover, upregulated AKT is postulated to be involved in increased cell proliferation and reduced apoptosis in OSCC. CONCLUSION: The gene expression analysis was done in the samples of histologically confirmed OSCC, and it revealed that the AKT gene was significantly upregulated in OSCC tissues. Thus, AKT could be postulated as a potential therapeutic target for OSCC.

Xuebijing improves intestinal microcirculation dysfunction in septic rats by regulating the VEGF-A/PI3K/Akt signaling pathway.

BACKGROUND: This study aims to explore whether Xuebijing (XBJ) can improve intestinal microcirculation dysfunction in sepsis and its mechanism. METHODS: A rat model of sepsis was established by cecal ligation and puncture (CLP). A total of 30 male SD rats were divided into four groups: sham group, CLP group, XBJ + axitinib group, and XBJ group. XBJ was intraperitoneally injected 2 h before CLP. Hemodynamic data (blood pressure and heart rate) were recorded. The intestinal microcirculation data of the rats were analyzed via microcirculation imaging. Enzyme-linked immunosorbent assay (ELISA) kits were used to detect the serum levels of interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor-α (TNF-α) in the rats. Histological analysis and transmission electron microscopy were used to analyze the injury of small intestinal microvascular endothelial cells and small intestinal mucosa in rats. The expression of vascular endothelial growth factor A (VEGF-A), phosphoinositide 3-kinase (PI3K), phosphorylated PI3K (p-PI3K), protein kinase B (Akt), and phosphorylated Akt (p-Akt) in the small intestine was analyzed via Western blotting. RESULTS: XBJ improved intestinal microcirculation dysfunction in septic rats, alleviated the injury of small intestinal microvascular endothelial cells and small intestinal mucosa, and reduced the systemic inflammatory response. Moreover, XBJ upregulated the expression of VEGF-A, p-PI3K/total PI3K, and p-Akt/total Akt in the rat small intestine. CONCLUSION: XBJ may improve intestinal microcirculation dysfunction in septic rats possibly through the VEGF-A/PI3K/Akt signaling pathway.

TRAF6-mediated ubiquitination of AKT1 in the nucleus occurs in a ß-arrestin2-dependent manner upon insulin stimulation.

AKT, also known as protein kinase B (PKB), serves as a crucial regulator of numerous biological functions, including cell growth, metabolism, and tumorigenesis. Increasing evidence suggests that the kinase activity of AKT is regulated via ubiquitination by various E3 ligase enzymes in response to different stimuli. However, the molecular mechanisms underlying insulin-induced AKT ubiquitination are not yet fully understood. Here, we show that activation of the insulin receptor (IR) leads to enhanced ubiquitination of AKT1 at K8 and K14 residues, facilitated by the cytosolic E3 ubiquitin ligase enzyme, TRAF6. Further investigation using AKT1 mutants with modified nucleocytoplasmic shuttling properties reveals that TRAF6-mediated AKT1 ubiquitination occurs within the nucleus in a ß-Arr2-dependent manner. The nuclear entry of TRAF6 depends on importin ß1, while ß-Arr2 regulates this process by facilitating the interaction between TRAF6 and importin ß1. Additionally, the ubiquitination of AKT1 is essential for its translocation to the activated IR on the plasma membrane, where it plays a functional role in recruiting Glut4 and facilitating glucose uptake. This study uncovers the cellular components and processes involved in insulin-induced ubiquitination and activation of AKT1, providing insights and detailed strategies for manipulating AKT1.

The association between endometrial polyps and insulin resistance from the expression of PI3K and AKT proteins perspective.

BACKGROUND: Insulin resistance (IR) induces hyperinsulinemia, which activates downstream signaling pathways such as the phosphatidylinositol-3-kinase/protein kinase B (PI3K/AKT) pathway, ultimately leading to abnormal proliferation and apoptosis of endometrial cells. This is thought to be a key pathogenic mechanism underlying the development of endometrial polyps (EP). This study aims to investigate the relationship between IR and the development of EP, the expression levels of downstream signaling molecules, including PI3K and AKT, and related laboratory parameters were examined. METHODS: A total of 100 patients who visited the gynecology outpatient clinic of Zhongda Hospital affiliated with Southeast University from May 2021 to March 2023 and were diagnosed with abnormal endometrial echoes by vaginal ultrasound and underwent hysteroscopic diagnostic curettage were enrolled in this study. General data and relevant hematological indicators were compared, and intraoperative specimens were obtained for pathological examination. Possible factors influencing the development of endometrial polyps were analyzed using Pearson correlation analysis and logistic regression analysis. RESULTS: In terms of body mass index, waist circumference, fasting insulin, insulin resistance index, serum total testosterone, and free testosterone index, women of childbearing age in the endometrial polyp group had higher values than those in the non-polyp group, while sex hormone-binding globulin in the endometrial polyp group was lower than that in the non-polyp group, and the differences were statistically significant (P < 0.05). The expression scores and mRNA expression levels of PI3K and AKT proteins were higher in the EP group than in the non-EP group (p < 0.05). Pearson correlation analysis showed a positive correlation between HOMA-IR and the expression scores of PI3K and AKT proteins (p < 0.01). CONCLUSIONS: Insulin resistance and abnormal activation of the phosphatidylinositol 3-kinase/protein kinase B signaling pathway may be potential pathogenic mechanisms for the development of endometrial polyps.

Inhibition of EGFR attenuates EGF-induced activation of retinal pigment epithelium cell via EGFR/AKT signaling pathway.

AIM: To explore the effect of epidermal growth factor receptor (EGFR) inhibition by erlotinib and EGFR siRNA on epidermal growth factor (EGF)-induced activation of retinal pigment epithelium (RPE) cells. METHODS: Human RPE cell line (ARPE-19 cells) was activated by 100 ng/mL EGF. Erlotinib and EGFR siRNA were used to intervene EGF treatment. Cellular viability, proliferation, and migration were detected by methyl thiazolyl tetrazolium (MTT) assay, bromodeoxyuridine (BrdU) staining assay and wound healing assay, respectively. EGFR/protein kinase B (AKT) pathway proteins and N-cadherin, α-smooth muscle actin (α-SMA), and vimentin were tested by Western blot assay. EGFR was also determined by immunofluorescence staining. RESULTS: EGF treatment for 24h induced a significant increase of ARPE-19 cells' viability, proliferation and migration, phosphorylation of EGFR/AKT proteins, and decreased total EGFR expression. Erlotinib suppressed ARPE-19 cells' viability, proliferation and migration through down regulating total EGFR and AKT protein expressions. Erlotinib also inhibited EGF-induced an increase of proliferative and migrative ability in ARPE-19 cells and clearly suppressed EGF-induced EGFR/AKT proteins phosphorylation and decreased expression of N-cadherin, α-SMA, and vimentin proteins. Similarly, EGFR inhibition by EGFR siRNA significantly affected EGF-induced an increase of cell proliferation, viability, and migration, phosphorylation of EGFR/AKT proteins, and up-regulation of N-cadherin, α-SMA, and vimentin proteins. CONCLUSION: Erlotinib and EGFR-knockdown suppress EGF-induced cell viability, proliferation, and migration via EGFR/AKT pathway in RPE cells. EGFR inhibition may be a possible therapeutic approach for proliferative vitreoretinopathy (PVR).

Scorpiones, Scolopendra and Gekko Inhibit Lung Cancer Growth and Metastasis by Ameliorating Hypoxic Tumor Microenvironment via PI3K/AKT/mTOR/HIF-1α Signaling Pathway.

OBJECTIVE: To investigate whether Buthus martensii karsch (Scorpiones), Scolopendra subspinipes mutilans L. Koch (Scolopendra) and Gekko gecko Linnaeus (Gekko) could ameliorate the hypoxic tumor microenvironment and inhibit lung cancer growth and metastasis by regulating phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin/hypoxia-inducible factor-1α (PI3K/AKT/mTOR/HIF-1α) signaling pathway. METHODS: Male C57BL/6J mice were inoculated with luciferase labeled LL/2-luc-M38 cell suspension to develop lung cancer models, with rapamycin and cyclophosphamide as positive controls. Carboxy methyl cellulose solutions of Scorpiones, Scolopendra and Gekko were administered intragastrically as 0.33, 0.33, and 0.83 g/kg, respectively once daily for 21 days. Fluorescent expression were detected every 7 days after inoculation, and tumor growth curves were plotted. Immunohistochemistry was performed to determine CD31 and HIF-1α expressions in tumor tissue and microvessel density (MVD) was analyzed. Western blot was performed to detect the expression of PI3K/AKT/mTOR/HIF-1α signaling pathway-related proteins. Enzyme-linked immunosorbent assay was performed to detect serum basic fibroblast growth factor (bFGF), transforming growth factor-ß1 (TGF-ß1) and vascular endothelial growth factor (VEGF) in mice. RESULTS: Scorpiones, Scolopendra and Gekko prolonged the survival time and inhibited lung cancer metastasis and expression of HIF-1α (all P<0.01). Moreover, Scorpiones, Scolopendra and Gekko inhibited the phosphorylation of AKT and ribosomal protein S6 kinase (p70S6K) (P<0.05 or P<0.01). In addition, they also decreased the expression of CD31, MVD, bFGF, TGF-ß1 and VEGF compared with the model group (P<0.05 or P<0.01). CONCLUSION: Scorpiones, Scolopendra and Gekko all showed beneficial effects on lung cancer by ameliorating the hypoxic tumor microenvironment via PI3K/AKT/mTOR/HIF-1α signaling pathway.

Ilicicolin C suppresses the progression of prostate cancer by inhibiting PI3K/AKT/mTOR pathway.

Aberrant activation of the PI3K/AKT pathway is a driving factor in the development of prostate cancer. Therefore, inhibiting the function of the PI3K/AKT signaling pathway is a strategy for the treatment of prostate cancer. Ilicicolin C is an ascochlorin derivative isolated from the coral-derived fungus Acremonium sclerotigenum GXIMD 02501. Which has anti-inflammatory activity, but its activity against prostate cancer has not yet been elucidated. MTT assay, plate clone-formation assay, flow cytometry and real-time cell analysis technology were used to detect the effects of ilicicolin C on cell viability, proliferation, apoptosis and migration of prostate cancer cells. Molecular docking software and surface plasmon resonance technology were used to analyze the interaction between ilicicolin C and PI3K/AKT proteins. Western blot assay was performed to examine the changes in protein expression. Finally, QikProp software was used to simulate the process of ilicicolin C in vivo, and a zebrafish xenograft model was used to further verify the anti-prostate cancer activity of ilicicolin C in vivo. Ilicicolin C showed cytotoxic effects on prostate cancer cells, with the most significant effect on PC-3 cells. Ilicicolin C inhibited proliferation and migration of PC-3 cells. It could also block the cell cycle and induce apoptosis in PC-3 cells. In addition, ilicicolin C could bind to PI3K/AKT proteins. Furthermore, ilicicolin C inhibited the expression of PI3K, AKT and mTOR proteins and could also regulate the expression of downstream proteins in the PI3K/AKT/mTOR signaling pathway. Moreover, the calculations speculated that ilicicolin C was well absorbed orally, and the zebrafish xenograft model confirmed the in vivo anti-prostate cancer effect of ilicicolin C. Ilicicolin C emerges as a promising marine compound capable of inducing apoptosis of prostate cancer cells by counteracting the aberrant activation of PI3K/AKT/mTOR, suggesting that ilicicolin C may be a viable candidate for anti-prostate cancer drug development. These findings highlight the potential of ilicicolin C against prostate cancer and shed light on its mechanism of action.

Loss of SAV1 in Kidney Proximal Tubule Induces Maladaptive Repair after Ischemia and Reperfusion Injury.

Kidney ischemia and reperfusion injury (IRI) is a significant contributor to acute kidney injury (AKI), characterized by tubular injury and kidney dysfunction. Salvador family WW domain containing protein 1 (SAV1) is a key component of the Hippo pathway and plays a crucial role in the regulation of organ size and tissue regeneration. However, whether SAV1 plays a role in kidney IRI is not investigated. In this study, we investigated the role of SAV1 in kidney injury and regeneration following IRI. A proximal tubule-specific knockout of SAV1 in kidneys (SAV1ptKO) was generated, and wild-type and SAV1ptKO mice underwent kidney IRI or sham operation. Plasma creatinine and blood urea nitrogen were measured to assess kidney function. Histological studies, including periodic acid-Schiff staining and immunohistochemistry, were conducted to assess tubular injury, SAV1 expression, and cell proliferation. Western blot analysis was employed to assess the Hippo pathway-related and proliferation-related proteins. SAV1 exhibited faint expression in the proximal tubules and was predominantly expressed in the connecting tubule to the collecting duct. At 48 h after IRI, SAV1ptKO mice continued to exhibit severe kidney dysfunction, compared to attenuated kidney dysfunction in wild-type mice. Consistent with the functional data, severe tubular damage induced by kidney IRI in the cortex was significantly decreased in wild-type mice at 48 h after IRI but not in SAV1ptKO mice. Furthermore, 48 h after IRI, the number of Ki67-positive cells in the cortex was significantly higher in wild-type mice than SAV1ptKO mice. After IRI, activation and expression of Hippo pathway-related proteins were enhanced, with no significant differences observed between wild-type and SAV1ptKO mice. Notably, at 48 h after IRI, protein kinase B activation (AKT) was significantly enhanced in SAV1ptKO mice compared to wild-type mice. This study demonstrates that SAV1 deficiency in the kidney proximal tubule worsens the injury and delays kidney regeneration after IRI, potentially through the overactivation of AKT.