Macrophage activation syndrome (MAS) is a life-threatening condition, characterized by cytopenia, multi-organ dysfunction, and coagulopathy associated with excessive activation of macrophages. In this study, we investigated the roles of alpha2-antiplasmin (α2AP) in the progression of MAS using fulminant MAS mouse model induced by toll-like receptor-9 agonist (CpG) and D-(+)-galactosamine hydrochloride (DG). α2AP deficiency attenuated macrophage accumulation, liver injury, and fibrin deposition in the MAS model mice.
View Article and Find Full Text PDFPreviously, using three types of cationic lipids, the effect of phospholipids in liposomal formulations on gene-knockdown efficacy was determined after and transfection with small interfering RNA (siRNA)/cationic liposome complexes (siRNA lipoplexes) containing various cationic lipids and phospholipids. In the present study, six other types of cationic lipids, namely -dimethyl--tetradecyltetradecan-1-aminium bromide, -hexadecyl--dimethylhexadecan-1-aminium bromide (DC-1-16), 2-[bis{2-(tetradecanoyloxy)ethyl}amino]--trimethyl-2-oxoethan-1-aminium chloride (DC-6-14), 1,2-di--octadecenyl-3-trimethylammonium propane chloride (DOTMA), 1,2-distearoyl-3-trimethylammonium-propane chloride (DSTAP) and 1,2-dioleoyl-3-dimethylammonium-propane were selected, and the effect of phospholipids in liposomal formulations containing each cationic lipid on gene-knockdown was evaluated. A total of 30 types of cationic liposomes composed of each cationic lipid with phosphatidylethanolamine containing unsaturated or saturated diacyl chains (C14, C16 or C18) were prepared.
View Article and Find Full Text PDFJ Basic Clin Physiol Pharmacol
September 2022
Objectives: Depression is a psychiatric disorder that affects about 10% of the world's population and is accompanied by anxiety. Depression and anxiety are often caused by various stresses. However, the etiology of depression and anxiety remains unknown.
View Article and Find Full Text PDFBackground: Diabetic nephropathy (DN), is microvascular complication of diabetes causes to kidney dysfunction and renal fibrosis. It is known that hyperglycemia and advanced glycation end products (AGEs) produced by hyperglycemic condition induce myofibroblast differentiation and endothelial-to-mesenchymal transition (EndoMT), and exacerbate fibrosis in DN. Recently, we demonstrated that α2-antiplasmin (α2AP) is associated with inflammatory response and fibrosis progression.
View Article and Find Full Text PDFCationic liposomes can be intravenously injected to deliver short interfering (si)RNAs into the lungs. The present study investigated the effects of sterol derivatives in systemically injected siRNA/cationic liposome complexes (siRNA lipoplexes) on gene‑knockdown in the lungs of mice. Cationic liposomes composed of 1,2‑dioleoyl‑3‑trimethylammonium‑propane or dimethyldioctadecylammonium bromide (DDAB) were prepared as a cationic lipid, with sterol derivatives such as cholesterol (Chol), β‑sitosterol, ergosterol (Ergo) or stigmasterol as a neutral helper lipid.
View Article and Find Full Text PDFSystemic sclerosis (SSc) is characterized by peripheral circulatory disturbance and fibrosis in skin and visceral organs. We recently demonstrated that α2-antiplasmin (α2AP) is elevated in SSc dermal fibroblasts and SSc model mice, and is associated with fibrosis progression and vascular dysfunction. In the present study, we predicted that α2AP could be a target of microRNA-30c (miR-30c) using TargetScan online database, and investigated the effect of miR-30c on the pathogenesis of SSc using a bleomycin-induced SSc model mice.
View Article and Find Full Text PDFPolyethylene glycol (PEG)‑modifications (PEGylations) of cationic liposome/small interfering RNA complexes (siRNA lipoplexes) can enhance their systemic stability. The present study determined the effects of PEG anchors in PEGylated siRNA lipoplexes on in vitro gene‑silencing effects and siRNA biodistribution after intravenous injection. Three types of dialkyl or trialkyl cationic lipids were used in the current study for the preparation of cationic liposomes.
View Article and Find Full Text PDFIn this study, we examined the effect of cationic lipid type in folate (FA)-polyethylene glycol (PEG)-modified cationic liposomes on gene-silencing effects in tumor cells using cationic liposomes/siRNA complexes (siRNA lipoplexes). We used three types of cationic cholesterol derivatives, cholesteryl (3-((2-hydroxyethyl)amino)propyl)carbamate hydroiodide (HAPC-Chol), -(2-(2-hydroxyethylamino)ethyl)cholesteryl-3-carboxamide (OH-Chol), and cholesteryl (2-((2-hydroxyethyl)amino)ethyl)carbamate (OH-C-Chol), and we prepared three types of FA-PEG-modified siRNA lipoplexes. The modification of cationic liposomes with 1-2 mol % PEG-lipid abolished the gene-silencing effect in human nasopharyngeal tumor KB cells, which overexpress the FA receptor (FR).
View Article and Find Full Text PDFBackground: The immunotherapies against cancer, autoinmmune diseases or infection are remarkable development. These days programmed cell death (PD)-1 antibody-induced immune checkpoint blockade or chimeric antigen receptor-T cells (CAR-T) have been shown to have eminent therapeutic effects on tumor development. We have focused on adoptive transfer with human gamma delta T cells for novel immunotherapies.
View Article and Find Full Text PDFCationic liposomes composed of dialkyl cationic lipid such as 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) can efficiently deliver siRNA to the lungs following the intravenous injection of cationic liposome/siRNA complexes (lipoplexes). In this study, we examined the effect of cationic lipid of cationic liposomes on siRNA delivery to the lungs after intravenous injection. We used six kinds of cationic cholesterol derivatives and 11 kinds of dialkyl or trialkyl cationic lipids as cationic lipids, and prepared 17 kinds of cationic liposomes composed of a cationic lipid and 1,2-dioleoyl-L-α-glycero-3-phosphatidylethanolamine (DOPE) for evaluation of siRNA biodistribution and in vivo gene silencing effects.
View Article and Find Full Text PDFBackground: Transcriptional regulation is a very important and pivotal function in myriad biological responses. Thus, methods to determine transcriptional activity are required in not only basic medical research but also in drug discovery. We established novel reporter constructs using human secreted embryonic alkaline phosphatase (SEAP) and Epstein-Barr virus nuclear antigen (EBNA) 1, which can maintain constructs synchronized to host cell replication.
View Article and Find Full Text PDFIt has been reported that suppression of protein kinase N3 (PKN3) expression in vascular and lymphatic endothelial cells results in the inhibition of tumor progression and lymph node metastasis formation. The present study investigated whether combination therapy of small interfering RNA (siRNA) against PKN3 and doxorubicin (DXR) could increase therapeutic efficacy against liver and lung metastases. transfection of PKN3 siRNA into PKN3-positive MDA-MB-231, LLC, and Colon 26 cells and PKN3-negative MCF-7 cells did not inhibit cell growth and did not increase sensitivity to DXR.
View Article and Find Full Text PDFMitotic progression is regulated by the phosphorylation of heat shock transcription factor 1 (HSF1) by polo-like kinase 1 (PLK1); however, this interaction is often deregulated in tumors. High expression levels of PLK1 and HSF1 have been observed in various types of human cancer. In the present study, it was investigated whether small interfering (si)RNA against PLK1 or HSF1 could suppress tumor growth and .
View Article and Find Full Text PDFThe intracellular cysteine protease caspase-1 is critically involved in obesity-induced inflammation in adipose tissue. A substantial body of evidence from immune cells, such as macrophages, has shown that caspase-1 activation depends largely on a protein complex, called the NLRP3 inflammasome, which consists of the NOD-like receptor (NLR) family protein NLRP3, the adaptor protein ASC, and caspase-1 itself. However, it is not fully understood how caspase-1 activation is regulated within adipocytes upon inflammatory stimuli.
View Article and Find Full Text PDFAm J Physiol Endocrinol Metab
April 2016
Extracellular signal-regulated kinase (ERK) has been implicated in the development of insulin resistance associated with obesity and type 2 diabetes mellitus. We have now examined the potential of pharmacological targeting of the ERK pathway with MEK (ERK kinase) inhibitors (PD184352 and PD0325901) for the treatment of obesity-associated insulin resistance. The effects of PD184352 and PD0325901 on the expression of adipocytokines and lipolysis activity were thus examined in 3T3-L1 adipocytes maintained in long-term culture as a model of adipocyte hypertrophy.
View Article and Find Full Text PDFPreviously, we developed a novel siRNA transfer method to the liver by sequential intravenous injection of anionic polymer and cationic liposome/siRNA complex (cationic lipoplex). In this study, we investigated whether siRNA delivered by this sequential injection could significantly suppress mRNA expression of the targeted gene in liver metastasis and inhibit tumor growth. When cationic lipoplex was intravenously injected into mice bearing liver metastasis of human breast tumor MCF-7 at 1 min after intravenous injection of chondroitin sulfate C (CS) or poly-l-glutamic acid (PGA), siRNA was accumulated in tumor-metastasized liver.
View Article and Find Full Text PDFPreviously, we found that the injection of zoledronic acid (ZOL) into mice bearing tumor induced changes of the vascular structure in the tumor. In this study, we examined whether ZOL treatment could decrease interstitial fluid pressure (IFP) via change of tumor vasculature, and enhance the antitumor efficacy of liposomal doxorubicin (Doxil®). When ZOL solution was injected at 40 µg/mouse per day for three consecutive days into mice bearing murine Lewis lung carcinoma LLC tumor, depletion of macrophages in tumor tissue and decreased density of tumor vasculature were observed.
View Article and Find Full Text PDFThe ERK pathway is up-regulated in various human cancers and represents a prime target for mechanism-based approaches to cancer treatment. Specific blockade of the ERK pathway alone induces mostly cytostatic rather than pro-apoptotic effects, however, resulting in a limited therapeutic efficacy of the ERK kinase (MEK) inhibitors. We previously showed that MEK inhibitors markedly enhance the ability of histone deacetylase (HDAC) inhibitors to induce apoptosis in tumor cells with constitutive ERK pathway activation in vitro.
View Article and Find Full Text PDFIt has generally been considered that protein phosphatases have more diverse catalytic domain structures and mechanisms than protein kinases; however, gene annotation efforts following the human genome project appeared to have completed the whole array of protein phosphatases. Ser/Thr phosphatases are divided into three subfamilies that have different structures from each other, whereas Tyr phosphatases and dual-specificity phosphatases targeting Tyr, Ser and Thr belong to a single large family based on their common structural features. Several years of research have revealed, however, the existence of unexpected proteins, designated here as "atypical protein phosphatases", that have structural and enzymatic features different from those of the known protein phosphatases and are involved in important biological processes.
View Article and Find Full Text PDFThe extracellular signal-regulated kinase (ERK) pathway is a major determinant in the control of diverse cellular processes such as proliferation, survival, and motility. This pathway is often upregulated in human cancers and as such represents an attractive target for mechanism-based approaches to cancer treatment. However, specific blockade of the ERK pathway alone induces mostly cytostatic rather than proapoptotic effects, resulting in limited therapeutic efficacy.
View Article and Find Full Text PDFPurpose: The extracellular signal-regulated kinase (ERK) pathway is upregulated in human cancers and represents a target for mechanism-based approaches to cancer treatment. However, specific blockade of the ERK pathway alone induces mostly cytostatic rather than proapoptotic effects, resulting in a limited therapeutic efficacy of inhibitors that target the mitogen-activated protein kinase/ERK kinase (MEK). Given the cytoprotective role of the ERK pathway, we examined whether its blockade by the MEK inhibitor PD184352 might enhance the therapeutic efficacy of anticancer drugs in human tumor xenograft models.
View Article and Find Full Text PDFDeregulated activation of protein tyrosine kinases, such as the epidermal growth factor receptor (EGFR) and Abl, is associated with human cancers including non-small cell lung cancer (NSCLC) and chronic myeloid leukemia (CML). Although inhibitors of such activated kinases have proved to be of therapeutic benefit in individuals with NSCLC or CML, some patients manifest intrinsic or acquired resistance to these drugs. We now show that, whereas blockade of either the extracellular signal-regulated kinase (ERK) pathway or the phosphatidylinositol 3-kinase (PI3K)-Akt pathway alone induced only a low level of cell death, it markedly sensitized NSCLC or CML cells to the induction of apoptosis by histone deacetylase (HDAC) inhibitors.
View Article and Find Full Text PDFThe extracellular signal-regulated kinase (ERK) signaling pathway is constitutively activated in many human tumor cell types. Given the cytoprotective role of this pathway, we examined whether its specific blockade might sensitize human tumor cells to the induction of apoptosis by various anticancer drugs. Although blockade of ERK signaling alone did not induce substantial cell death, it resulted in marked and selective enhancement of the induction of apoptosis by microtubule-destabilizing agents in tumor cells in which the ERK pathway is constitutively activated.
View Article and Find Full Text PDFAlthough DNA-damaging agents are among the most effective anticancer drugs in clinical use, their overall effectiveness is limited by the development of cross-resistance to these drugs. Given that histone deacetylase (HDAC) inhibitors increase the acetylation of core histones, resulting in an open chromatin configuration that is more accessible to DNA-targeting agents, we examined whether HDAC inhibitors might enhance the cytotoxicity of DNA-damaging drugs in six human ovarian tumor cell lines that exhibit different cisplatin sensitivities. Low concentrations of HDAC inhibitors, which alone exhibited little cytotoxicity, markedly enhanced the induction of apoptotic cell death not only by cisplatin but also by a wide variety of DNA-targeting anticancer drugs in these tumor cell lines, irrespective of their sensitivities to the respective drugs.
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