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Megalin receptor-mediated endocytosis participates a crucial role in gentamicin (GM) uptake, accumulation, and toxicity. In this study, we investigated the potential effects of montelukast (MLK) on megalin expression/endocytic function against GM nephrotoxicity. Male Wistar rats were administered GM (120 mg/kg; i.p.) daily in divided doses along 4 hr; 30 mg/kg/hr; for 7 days. MLK (30 mg/kg/day) was orally administered 7 days before and then concurrently with GM. The protein expressions of megalin and chloride channel-5 (ClC-5); one of the essential regulators of megalin endocytic function; were determined by Western blotting. Besides, the endocytic function of megalin was evaluated by the uptake of bovine serum albumin labeled with fluorescein isothiocyanate (FITC-BSA) into proximal tubular epithelial cells. Moreover, kidney function biomarkers (Cr, BUN, GFR, KIM-1, cystatin-C) and apoptosis markers (p-AKT1, cleaved caspase-3) were estimated. Co-treatment with MLK downregulated ClC-5 expression leading to reduced recycling of megalin to the plasma membrane, reduced expression, and so impaired endocytic function that was evidenced by reduced uptake of FITC-BSA in proximal tubular epithelial cells. The protein expression of the apoptotic executioner cleaved caspase-3 was significantly reduced, while that of the antiapoptotic p-AKT1 was elevated. These results were confirmed by the improvement of kidney functions and histological findings. Our data suggest that MLK could interfere with megalin expression/endocytic function that could be attributed to downregulation of ClC-5 protein expression. That eventually reduces renal cell apoptosis and improves kidney functions after GM administration without affecting the antibacterial activity of GM. Therefore, reduced expression of ClC-5 and interference with megalin expression/endocytic function by MLK could be an effective strategy against GM nephrotoxicity.
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The importance of the tumor microenvironment in cancer progression has been well studied for many years. Immune checkpoint inhibitors (ICIs) are regarded as potential strategies in enhancing the immune responses in patients with cancer, particularly colorectal cancer (CRC). Notably, CRCs are extraordinarily heterogeneous and mostly are microsatellite-stable (MSS) or cold tumors, which means that the immune response is not usually as strong as that of foreign cells. T-cell immunoglobulin and ITIM domain (TIGIT) is a new immune checkpoint receptor overexpressed inside the CRC tumor-immune microenvironments. Moreover, several studies have shown that TIGIT in combination with other ICIs and/or conventional treatments, can lead to a robust anti-tumor response in CRC. This review looks deep inside TIGIT expression patterns, their various functions, and possible immunotherapy strategies to increase survival rates and decrease immune-related adverse events.
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Adenocarcinoma/terapia , Neoplasias Colorretais/terapia , Inibidores de Checkpoint Imunológico , Proteínas de Checkpoint Imunológico/imunologia , Imunoterapia/métodos , Receptores Imunológicos/antagonistas & inibidores , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Motivos de Aminoácidos , Animais , Antígenos CD/imunologia , Sistemas CRISPR-Cas , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/radioterapia , Terapia Combinada , Microbioma Gastrointestinal , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Prognóstico , Domínios Proteicos , Receptores Imunológicos/biossíntese , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Microambiente TumoralRESUMO
One of the most common malignant tumors is hepatocellular carcinoma (HCC). Progression of HCC mainly results from highly complex molecular and pathological pathways. Midkine (MDK) is a growth factor that impacts viability, migration, and other cell activities. Since MDK has been involved in the inflammatory responses, it has been claimed that MDK has a crucial role in HCC. MDK acts as an anti-apoptotic factor, which mediates tumor cell viability. In addition, MDK blocks anoikis to promote metastasis. There is also evidence that MDK is involved in angiogenesis. It has been shown that the application of anti-MDK approaches might be promising in the treatment of HCC. Besides, due to the elevated expression in HCC, MDK has been proposed as a biomarker in the prognosis and diagnosis of HCC. In this review, we will discuss the role of MDK in HCC. It is hoped that the development of new strategies concerning MDK-based therapies will be promising in HCC management.
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Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Midkina/fisiologia , Animais , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patologia , Terapia Genética/métodos , Humanos , Imunoterapia/métodos , Fígado/irrigação sanguínea , Fígado/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Midkina/sangue , Midkina/química , Neovascularização Patológica/metabolismo , Interferência de RNARESUMO
Breast cancer is the most common cancer that majorly affects female. The present study is focused on exploring the potential anticancer activity of 2-((1, 2, 3, 4-Tetrahydroquinolin-1-yl) (4 methoxyphenyl) methyl) phenol (THMPP), against human breast cancer. The mechanism of action, activation of specific signaling pathways, structural activity relationship and drug-likeness properties of THMPP remains elusive. Cell proliferation and viability assay, caspase enzyme activity, DNA fragmentation and FITC/Annexin V, AO/EtBr staining, RT-PCR, QSAR and ADME analysis were executed to understand the mode of action of the drug. The effect of THMPP on multiple breast cancer cell lines (MCF-7 and SkBr3), and non-tumorigenic cell line (H9C2) was assessed by MTT assay. THMPP at IC50 concentration of 83.23 µM and 113.94 µM, induced cell death in MCF-7 and SkBr3 cells, respectively. Increased level of caspase-3 and -9, fragmentation of DNA, translocation of phosphatidylserine membrane and morphological changes in the cells confirmed the effect of THMPP in inducing the apoptosis. Gene expression analysis has shown that THMPP was able to downregulate the expression of PI3K/S6K1 genes, possibly via EGFR signaling pathway in both the cell lines, MCF-7 and SkBr3. Further, molecular docking also confirms the potential binding of THMPP with EGFR. QSAR and ADME analysis proved THMPP as an effective anti-breast cancer drug, exhibiting important pharmacological properties. Overall, the results suggest that THMPP induced cell death might be regulated by EGFR signaling pathway which augments THMPP being developed as a potential candidate for treating breast cancer.
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Muscle fibre types can transform from slow-twitch (slow myosin heavy chain (MyHC)) to fast-twitch (fast MyHC) or vice versa. Leucine plays a vital effect in the development of skeletal muscle. However, the role of leucine in porcine myofibre type transformation and its mechanism are still unclear. In this study, effects of leucine and microRNA-27a (miR-27a) on the transformation of porcine myofibre type were investigated in vitro. We found that leucine increased slow MyHC protein level and decreased fast MyHC protein level, increased the levels of phospho-protein kinase B (Akt)/Akt and phospho-forkhead box 1 (FoxO1)/FoxO1 and decreased the FoxO1 protein level. However, blocking the Akt/FoxO1 signalling pathway by wortmannin attenuated the role of leucine in porcine myofibre type transformation. Over-expression of miR-27a decreased slow MyHC protein level and increased fast MyHC protein level, whereas inhibition of miR-27a had an opposite effect. We also found that expression of miR-27a was down-regulated following leucine treatment. Moreover, over-expression of miR-27a repressed transformation from fast MyHC to slow MyHC caused by leucine, suggesting that miR-27a is interdicted by leucine and then contributes to porcine muscle fibre type transformation. Our finding provided the first evidence that leucine promotes porcine myofibre type transformation from fast MyHC to slow MyHC via the Akt/FoxO1 signalling pathway and miR-27a.
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Proteína Forkhead Box O1/metabolismo , Leucina/farmacologia , MicroRNAs/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sus scrofa , Animais , Regulação para Baixo/efeitos dos fármacos , Masculino , MicroRNAs/genética , Fibras Musculares de Contração Rápida/efeitos dos fármacos , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares de Contração Lenta/efeitos dos fármacos , Fibras Musculares de Contração Lenta/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Inibidores de Proteínas Quinases , Transdução de Sinais/efeitos dos fármacos , Wortmanina/farmacologiaRESUMO
In the last 30â¯years, since the discovery that vanadium is a cofactor found in certain enzymes of tunicates and possibly in mammals, different vanadium-based drugs have been developed targeting to treat different pathologies. So far, the in vitro studies of the insulin mimetic, antitumor and antiparasitic activity of certain compounds of vanadium have resulted in a great boom of its inorganic and bioinorganic chemistry. Chemical speciation studies of vanadium with amino acids under controlled conditions or, even in blood plasma, are essential for the understanding of the biotransformation of e.g. vanadium antidiabetic complexes at the physiological level, providing clues of their mechanism of action. The present article carries out a bibliographical research emphaticizing the chemical speciation of the vanadium with different amino acids and reviewing also some other important aspects such as its chemistry and therapeutical applications of several vanadium complexes.
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Systemic lupus erythematosus (SLE) is an autoimmune disease that is characterised by a dysregulation of the immune system, which causes inflammation responses, excessive oxidative stress and a reduction in the number of cluster of differentiation (CD)4+CD25+forkhead box P3 (FoxP3)+ T cells. Supplementation with certain Lactobacillus strains has been suggested to be beneficial in the comprehensive treatment of SLE. However, little is known about the effect and mechanism of certain Lactobacillus strains on SLE. To investigate the effects of Lactobacillus on SLE, NZB/W F1 mice were orally gavaged with Lactobacillus paracasei GMNL-32 (GMNL-32), Lactobacillus reuteri GMNL-89 (GMNL-89) and L. reuteri GMNL-263 (GMNL-263). Supplementation with GMNL-32, GMNL-89 and GMNL-263 significantly increased antioxidant activity, reduced IL-6 and TNF-α levels and significantly decreased the toll-like receptors/myeloid differentiation primary response gene 88 signalling in NZB/W F1 mice. Notably, supplementation with GMNL-263, but not GMNL-32 and GMNL-89, in NZB/W F1 mice significantly increased the differentiation of CD4+CD25+FoxP3+ T cells. These findings reveal beneficial effects of GMNL-32, GMNL-89 and GMNL-263 on NZB/W F1 mice and suggest that these specific Lactobacillus strains can be used as part of a comprehensive treatment of SLE patients.
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Antioxidantes/metabolismo , Linfócitos T CD4-Positivos/citologia , Lactobacillus , Probióticos/administração & dosagem , Administração Oral , Animais , Linfócitos T CD4-Positivos/metabolismo , Modelos Animais de Doenças , Feminino , Fatores de Transcrição Forkhead/metabolismo , Glutationa/sangue , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Interleucina-6/sangue , Lactobacillus/classificação , Lúpus Eritematoso Sistêmico/terapia , Camundongos , Camundongos Endogâmicos NZB , RNA Mensageiro/sangue , Tiobarbitúricos/sangue , Receptores Toll-Like/sangue , Fator de Necrose Tumoral alfa/sangueRESUMO
Mechanistic target of rapamycin complex 1 (mTORC1) is a serine-threonine kinase that is activated by extracellular signals, such as nutrients and growth factors. It plays a key role in the control of various biological processes, such as protein synthesis and energy metabolism by mediating or regulating the phosphorylation of multiple target molecules, some of which remain to be identified. We have here reanalysed a large-scale phosphoproteomics data set for mTORC1 target molecules and identified pre-B cell leukemia transcription factor 2 (PBX2) as such a novel target that is dephosphorylated downstream of mTORC1. We confirmed that PBX2, but not other members of the PBX family, is dephosphorylated in an mTORC1 activity-dependent manner. Furthermore, pharmacological and gene knockdown experiments revealed that glycogen synthase kinase 3 (GSK3) and protein phosphatase 1 (PP1) are responsible for the phosphorylation and dephosphorylation of PBX2, respectively. Our results thus suggest that the balance between the antagonistic actions of GSK3 and PP1 determines the phosphorylation status of PBX2 and its regulation by mTORC1.
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Quinase 3 da Glicogênio Sintase , Transdução de Sinais , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fosforilação , Proteína Fosfatase 1/metabolismoRESUMO
Purpose: This study aimed to evaluate the neuroprotective ability of the conditioned medium of stem cells from human exfoliated deciduous teeth (CM-SHED) to prevent glutamate-induced apoptosis of neural progenitors. Materials and methods: Neural progenitors were isolated from two-day-old rat brains, and the conditioned medium was obtained from a mesenchymal stem cell SHED. Four groups were examined: neural progenitor cells cultured in neurobasal medium with (N + ) and without (N-) glutamate and glycine, and neural progenitor cells cultured in CM-SHED with (K + ) and without (K-) glutamate and glycine. Results: The expression of GABA A1 receptor (GABAAR1) messenger RNA (mRNA) in neural progenitor measured by real-time quantitative PCR. GABA contents were measured by enzyme-linked immunosorbent assay, whereas the apoptosis markers caspase-3 and 7-aminoactinomycin D were analysed with a Muse® cell analyzer. The viability of neural progenitor cells in the K + group (78.05 %) was higher than the control group N- (73.22 %) and lower in the N + group (68.90 %) than in the control group. The K + group showed the highest GABA content, which significantly differed from that in the other groups, whereas the lowest content was observed in the N + group. The expression level of GABAAR1 mRNA in the K + group was the highest compared to that in the other groups. CM-SHED potently protected the neural progenitors from apoptosis. Conclusions: CM-SHED may effectively prevent glutamate-induced apoptosis of neural progenitors.
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Introduction: Phosphoinositide 3-kinase gamma (PI3Kγ) has been regarded as a promising drug target for the treatment of various diseases, and the diverse physiological roles of class I PI3K isoforms (α, ß, δ, and γ) highlight the importance of isoform selectivity in the development of PI3Kγ inhibitors. However, the high structural conservation among the PI3K family makes it a big challenge to develop selective PI3Kγ inhibitors. Objectives: A novel machine learning-based virtual screening with multiple PI3Kγ protein structures was developed to discover novel PI3Kγ inhibitors. Methods: A large chemical database was screened using the virtual screening model, the top-ranked compounds were then subjected to a series of bio-evaluations, which led to the discovery of JN-KI3. The selective inhibition mechanism of JN-KI3 against PI3Kγ was uncovered by a theoretical study. Results: 49 hits were identified through virtual screening, and the cell-free enzymatic studies found that JN-KI3 selectively inhibited PI3Kγ at a concentration as low as 3,873 nM but had no inhibitory effect on Class IA PI3Ks, leading to the selective cytotoxicity on hematologic cancer cells. Meanwhile, JN-KI3 potently blocked the PI3K signaling, finally led to distinct apoptosis of hematologic cell lines at a low concentration. Lastly, the key residues of PI3Kγ and the structural characteristics of JN-KI3, which both would influence γ isoform-selective inhibition, were highlighted by systematic theoretical studies. Conclusion: The developed virtual screening model strongly manifests the robustness to find novel PI3Kγ inhibitors. JN-KI3 displays a specific cytotoxicity on hematologic tumor cells, and significantly promotes apoptosis associated with the inhibition of the PI3K signaling, which depicts PI3Kγ as a potential target for the hematologic tumor therapy. The theoretical results reveal that those key residues interacting with JN-KI3 are less common compared to most of the reported PI3Kγ inhibitors, indicating that JN-KI3 has novel structural characteristics as a selective PIK3γ inhibitor.
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Simulação de Dinâmica Molecular , Fosfatidilinositol 3-Quinases , Aprendizado de Máquina , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 QuinaseRESUMO
Cancer immunotherapy has become a new generation of anti-tumor treatment, but its indications still focus on several types of tumors that are sensitive to the immune system. Therefore, effective strategies that can expand its indications and enhance its efficiency become the key element for the further development of cancer immunotherapy. Natural products are reported to have this effect on cancer immunotherapy, including cancer vaccines, immune-check points inhibitors, and adoptive immune-cells therapy. And the mechanism of that is mainly attributed to the remodeling of the tumor-immunosuppressive microenvironment, which is the key factor that assists tumor to avoid the recognition and attack from immune system and cancer immunotherapy. Therefore, this review summarizes and concludes the natural products that reportedly improve cancer immunotherapy and investigates the mechanism. And we found that saponins, polysaccharides, and flavonoids are mainly three categories of natural products, which reflected significant effects combined with cancer immunotherapy through reversing the tumor-immunosuppressive microenvironment. Besides, this review also collected the studies about nano-technology used to improve the disadvantages of natural products. All of these studies showed the great potential of natural products in cancer immunotherapy.
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Objective: The pedicled greater omentum, when applied onto stressed hearts using omentopexy, has been shown to be protective in humans and animals. The mechanisms underlying cardioprotection using omentopexy remain elusive. This study examined whether macrophage-mediated angiogenesis accounts for the cardioprotective effect of omentopexy in mice. Methods: C57BL/6 mice were subjected to minimally invasive transverse aortic constriction for 6 weeks and subsequent cardio-omentopexy for 8 weeks. Control mice underwent the same surgical procedures without aortic constriction or cardio-omentopexy. Results: Transverse aortic constriction led to left ventricular concentric hypertrophy, reduced mitral E/A ratio, increased cardiomyocyte size, and myocardial fibrosis in the mice that underwent sham cardio-omentopexy surgery. The negative effects of transverse aortic constriction were prevented by cardio-omentopexy. Myocardial microvessel density was elevated in the mice that underwent aortic constriction and sham cardio-omentopexy surgery, and cardio-omentopexy further enhanced angiogenesis. Nanostring gene array analysis uncovered the activation of angiogenesis gene networks by cardio-omentopexy. Flow cytometric analysis revealed that cardio-omentopexy triggered the accumulation of cardiac MHCIIloLyve1+TimD4+ (Major histocompatibility complex class IIlow lymphatic vessel endothelial hyaluronan receptor 1+ T cell immunoglobulin and mucin domain conataining 4+) resident macrophages at the omental-cardiac interface. Intriguingly, the depletion of macrophages with clodronate-liposome resulted in the failure of cardio-omentopexy to protect the heart and promote angiogenesis. Conclusions: Cardio-omentopexy protects the heart from pressure overload-elicited left ventricular hypertrophy and dysfunction by promoting myocardial angiogenesis. Cardiac MHCIIloLyve1+TimD4+ resident macrophages play a critical role in the cardioprotective effect and angiogenesis of cardio-omentopexy.
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Transient receptor potential (TRP) channels are one primary type of calcium (Ca2+) permeable channels, and those relevant transmembrane and intracellular TRP channels were previously thought to be mainly associated with the regulation of cardiovascular and neuronal systems. Nowadays, however, accumulating evidence shows that those TRP channels are also responsible for tumorigenesis and progression, inducing tumor invasion and metastasis. However, the overall underlying mechanisms and possible signaling transduction pathways that TRP channels in malignant tumors might still remain elusive. Therefore, in this review, we focus on the linkage between TRP channels and the significant characteristics of tumors such as multi-drug resistance (MDR), metastasis, apoptosis, proliferation, immune surveillance evasion, and the alterations of relevant tumor micro-environment. Moreover, we also have discussed the expression of relevant TRP channels in various forms of cancer and the relevant inhibitors' efficacy. The chemo-sensitivity of the anti-cancer drugs of various acting mechanisms and the potential clinical applications are also presented. Furthermore, it would be enlightening to provide possible novel therapeutic approaches to counteract malignant tumors regarding the intervention of calcium channels of this type.
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Hepatocellular carcinoma (HCC) is an aggressive human cancer with increasing incidence worldwide. Multiple efforts have been made to explore pharmaceutical therapies to treat HCC, such as targeted tyrosine kinase inhibitors, immune based therapies and combination of chemotherapy. However, limitations exist in current strategies including chemoresistance for instance. Tumor initiation and progression is driven by reprogramming of metabolism, in particular during HCC development. Recently, metabolic associated fatty liver disease (MAFLD), a reappraisal of new nomenclature for non-alcoholic fatty liver disease (NAFLD), indicates growing appreciation of metabolism in the pathogenesis of liver disease, including HCC, thereby suggesting new strategies by targeting abnormal metabolism for HCC treatment. In this review, we introduce directions by highlighting the metabolic targets in glucose, fatty acid, amino acid and glutamine metabolism, which are suitable for HCC pharmaceutical intervention. We also summarize and discuss current pharmaceutical agents and studies targeting deregulated metabolism during HCC treatment. Furthermore, opportunities and challenges in the discovery and development of HCC therapy targeting metabolism are discussed.
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Fibroblast growth factor receptors (FGFRs) have emerged as promising targets for anticancer therapy. In this study, we synthesized and evaluated the biological activity of 66 pyrazolo[3,4-d]pyridazinone derivatives. Kinase inhibition, cell proliferation, and whole blood stability assays were used to evaluate their activity on FGFR, allowing us to explore structure-activity relationships and thus to gain understanding of the structural requirements to modulate covalent inhibitors' selectivity and reactivity. Among them, compound 10h exhibited potent enzymatic activity against FGFR and remarkably inhibited proliferation of various cancer cells associated with FGFR dysregulation, and suppressed FGFR signaling pathway in cancer cells by the immunoblot analysis. Moreover, 10h displayed highly potent antitumor efficacy (TGI = 91.6%, at a dose of 50 mg/kg) in the FGFR1-amplified NCI-H1581 xenograft model.
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Bone morphogenic proteins (BMPs) are important growth regulators in embryogenesis and postnatal homeostasis. Their tight regulation is crucial for successful embryonic development as well as tissue homeostasis in the adult organism. BMP inhibition by natural extracellular biologic antagonists represents the most intensively studied mechanistic concept of BMP growth factor regulation. It was shown to be critical for numerous developmental programs, including germ layer specification and spatiotemporal gradients required for the establishment of the dorsal-ventral axis and organ formation. The importance of BMP antagonists for extracellular matrix homeostasis is illustrated by the numerous human connective tissue disorders caused by their mutational inactivation. Here, we will focus on the known functional interactions targeting BMP antagonists to the ECM and discuss how these interactions influence BMP antagonist activity. Moreover, we will provide an overview about the current concepts and investigated molecular mechanisms modulating BMP inhibitor function in the context of development and disease.
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Metabolic syndrome (MS) refers to a clustering of at least three of the following medical conditions: high blood pressure, abdominal obesity, hyperglycemia, low high-density lipoprotein level, and high serum triglycerides. MS is related to a wide range of diseases which includes obesity, diabetes, insulin resistance, cardiovascular disease, dyslipidemia, or non-alcoholic fatty liver disease. There remains an ongoing need for improved treatment strategies for MS. The most important risk factors are dietary pattern, genetics, old age, lack of exercise, disrupted biology, medication usage, and excessive alcohol consumption, but pathophysiology of MS has not been completely identified. Korean Red Ginseng (KRG) refers to steamed/dried ginseng, traditionally associated with beneficial effects such as anti-inflammation, anti-fatigue, anti-obesity, anti-oxidant, and anti-cancer effects. KRG has been often used in traditional medicine to treat multiple metabolic conditions. This paper summarizes the effects of KRG in MS and related diseases such as obesity, cardiovascular disease, insulin resistance, diabetes, dyslipidemia, or non-alcoholic fatty liver disease based on experimental research and clinical studies.
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BACKGROUND: The Bruton's Tyrosine Kinase Inhibitor ibrutinib is associated with ventricular arrhythmia (VA) and sudden death. However, the pro-arrhythmic electrophysiological dysregulation that results from ibrutinib with age and cardiovascular disease is unknown. OBJECTIVES: This study sought to investigate the acute effects of ibrutinib on left ventricular (LV) VA vulnerability, cytosolic calcium dynamics, and membrane electrophysiology in old and young spontaneous hypertensive rats (SHRs). METHODS: Langendorff-perfused hearts of young (10 to 14 weeks) and old (10 to 14 months) SHRs were treated with ibrutinib (0.1 µmol/l) or vehicle for 30 min. Simultaneously, LV epicardial action potential and cytosolic calcium transients were optically mapped following an incremental pacing protocol. Calcium and action potential dynamics parameters were analyzed. VA vulnerability was assessed by electrically inducing ventricular fibrillations (VFs) in each heart. Western blot analysis was performed on LV tissues. RESULTS: Ibrutinib treatment resulted in higher vulnerability to VF in old SHR hearts (27.5 ± 7.5% vs. 5.7 ± 3.7%; p = 0.026) but not in young SHR hearts (8.0 ± 4.9% vs. 0%; p = 0.193). In old SHR hearts, following ibrutinib treatment, action potential duration (APD) alternans (p = 0.008) and APD alternans spatial discordance (p = 0.027) were more prominent. Moreover, calcium transient duration 50 was longer (p = 0.032), calcium amplitude alternans ratio was significantly lower (p = 0.001), and time-to-peak of calcium amplitude was shorter (p = 0.037). In young SHR hearts, there were no differences in calcium and APD dynamics. CONCLUSIONS: Ibrutinib-induced VA is associated with old age in SHR. Acute dysregulation of calcium and repolarization dynamics play important roles in ibrutinib-induced VF.
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Despite the functional role of serglycin as an intracellular proteoglycan, a variety of malignant cells depends on its expression and constitutive secretion to advance their aggressive behavior. Serglycin arose to be a biomarker for glioblastoma, which is the deadliest and most treatment-resistant form of brain tumor, but its role in this disease is not fully elucidated. In our study we suppressed the endogenous levels of serglycin in LN-18 glioblastoma cells to decipher its involvement in their malignant phenotype. Serglycin suppressed LN-18 (LN-18shSRGN) glioblastoma cells underwent astrocytic differentiation characterized by induced expression of GFAP, SPARCL-1 and SNAIL, with simultaneous loss of their stemness capacity. In particular, LN-18shSRGN cells presented decreased expression of glioma stem cell-related genes and ALDH1 activity, accompanied by reduced colony formation ability. Moreover, the suppression of serglycin in LN-18shSRGN cells retarded the proliferative and migratory rate, the invasive potential in vitro and the tumor burden in vivo. The lack of serglycin in LN-18shSRGN cells was followed by G2 arrest, with subsequent reduction of the expression of cell-cycle regulators. LN-18shSRGN cells also exhibited impaired expression and activity of proteolytic enzymes such as MMPs, TIMPs and uPA, both in vitro and in vivo. Moreover, suppression of serglycin in LN-18shSRGN cells eliminated the activation of pro-tumorigenic signal transduction. Of note, LN-18shSRGN cells displayed lower expression and secretion levels of IL-6, IL-8 and CXCR-2. Concomitant, serglycin suppressed LN-18shSRGN cells demonstrated repressed phosphorylation of ERK1/2, p38, SRC and STAT-3, which together with PI3K/AKT and IL-8/CXCR-2 signaling control LN-18 glioblastoma cell aggressiveness. Collectively, the absence of serglycin favors an astrocytic fate switch and a less aggressive phenotype, characterized by loss of pluripotency, block of the cell cycle, reduced ability for ECM proteolysis and pro-tumorigenic signaling attenuation.
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Liposomal drug-delivery systems (LDDs) provide a promising opportunity to precisely target organs, improve drug bioavailability and reduce systemic toxicity. On the other hand, PI3K/Akt signaling pathways control various intracellular functions including apoptosis, invasion and cell growth. Hyper activation of PI3K and Akt is detected in some types of cancer that posses defect in PTEN. Tracking the crosstalk between PI3K/Akt, PTEN and STAT 5A signaling pathways, in cancer could result in identifying new therapeutic agents. The current study, identified an over view on PI3K/Akt, PTEN and STAT-5A networks, in addition to their biological roles in hepatocellular carcinoma (HCC). In the current study galactomannan was extracted from Caesalpinia gilliesii seeds then loaded in liposomes. Liposomes were prepared employing phosphatidyl choline and different concentrations of cholesterol. HCC was then induced in Wistar albino rats followed by liposomal galactomannan (700 ± 100 nm) treatment. Liver enzymes as well as antioxidants were assessed and PI3K/Akt, PTEN and STAT-5A gene expression were investigated. The prepared vesicles revealed entrapment efficiencies ranging from 23.55 to 69.17%, and negative zeta potential values. The optimum formulation revealed spherical morphology as well as diffusion controlled in vitro release pattern. Liposomal galactomannan elucidated a significant reduction in liver enzymes and MDA as well as PI3K/Akt, PTEN and STAT 5A gene expression. A significant elevation in GST and GSH were deduced. In conclusion, Liposomal galactomannan revealed a promising candidate for HCC therapy.