Search results for "caspase 3"
showing 10 items of 173 documents
β-Amyloid-induced activation of Caspase-3 in primary cultures of rat neurons
2000
It is known that beta-amyloid peptide (Abeta) contributes to the neurodegeneration in Alzheimer's disease (AD) and operates through activation of an apoptotic pathway. Apoptotic signal is driven by a family of cysteine proteases called caspases. The beta-amyloid precursor protein (APP) is directly and efficiently cleaved by caspases during apoptosis, resulting in elevated beta-amyloid peptide formation. Cerebellar neurons from rat pups were treated with the aged Abeta(25-35) at 1 and 5 microM and fluorescence assays of caspase activity performed over 4 days. We observed an increase in caspase activity after 48 h treatment in both 1 and 5 microM treated cells, then (72-96 h) caspase activity…
Detection of mitochondrial electron chain carrier redox status by transhepatic light intensity during rat liver reperfusion.
2003
The aim of the study was to investigate mitochondrial electron transfer during rat liver reperfusion after cold storage and hypothermic machine perfusion. Livers from male Brown Norway rats were preserved (UW) for 10h either by cold storage (CS) or by hypothermic oxygenated perfusion extracorporal (HOPE). Transhepatic photometric analysis allowed determination of the redox status of mitochondrial cytochromes during preservation, rewarming and reperfusion. Mitochondrial electron chain carriers were inhibited at different sites with rotenone and cyanide in some experiments. reversed transcriptional polymerase chain reaction (RT-PCR) was performed after reperfusion concerning transcription of …
Exercise and Metformin Intervention Prevents Lipotoxicity-Induced Hepatocyte Apoptosis by Alleviating Oxidative and ER Stress and Activating the AMPK…
2022
Objective. Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes (T2DM) commonly coexist and act synergistically to drive adverse clinical outcomes. This study is aimed at investigating the effects of exercise intervention and oral hypoglycaemic drug of metformin (MET) alone or combined on hepatic lipid accumulation. To investigate if oxidative stress and endoplasmic reticulum stress (ERS) are involved in lipotoxicity-induced hepatocyte apoptosis in diabetic mice and whether exercise and/or MET alleviated oxidative stress or ERS-apoptosis by AMPK-Nrf2-HO-1 signaling pathway. Methods. Forty db/db mice with diabetes ( random blood glucose ≥ 250 mg / dL ) were randomly allocated i…
Beneficial Effect of Docosahexanoic Acid and Lutein on Retinal Structural, Metabolic, and Functional Abnormalities in Diabetic Rats
2009
To assess the effect of docosahexanoic acid (DHA) and lutein (both compounds with anti-inflammatory and antioxidant properties) on experimental diabetic retinopathy.Male Wistar rats were studied: non-diabetic controls, untreated diabetic controls, and diabetic rats were treated with DHA and lutein or the combination of DHA + insulin and lutein + insulin for 12 weeks. Oxidative stress and inflammatory markers, apoptosis, and functional tests were studied to confirm biochemical and functional changes in the retina of diabetic rats. Malondialdehyde (MDA), glutathione concentrations (GSH), and glutathione peroxidase activity (GPx) were measured as oxidative stress markers. TUNEL assay and caspa…
Mir-675-5p supports hypoxia-induced drug resistance in colorectal cancer cells.
2022
Abstract Background The uncontrolled proliferation of cancer cells determines hypoxic conditions within the neoplastic mass with consequent activation of specific molecular pathways that allow cells to survive despite oxygen deprivation. The same molecular pathways are often the cause of chemoresistance. This study aims to investigate the role of the hypoxia-induced miR-675-5p in 5-Fluorouracil (5-FU) resistance on colorectal cancer (CRC) cells. Methods CRC cell lines were treated with 5-Fu and incubated in normoxic or hypoxic conditions; cell viability has been evaluated by MTT assay. MiR-675-5p levels were analysed by RT-PCR and loss and gain expression of the miRNA has been obtained by t…
Ionizing radiation but not anticancer drugs causes cell cycle arrest and failure to activate the mitochondrial death pathway in MCF-7 breast carcinom…
2001
There is considerable evidence that ionizing radiation (IR) and chemotherapeutic drugs mediate apoptosis through the intrinsic death pathway via the release of mitochondrial cytochrome c and activation of caspases -9 and -3. Here we show that MCF-7 cells that lack caspase-3 undergo a caspase-dependent apoptotic cell death in the absence of DNA fragmentation and alpha-fodrin cleavage following treatment with etoposide or doxorubicin, but not after exposure to IR. Re-expression of caspase-3 restored DNA fragmentation and alpha-fodrin cleavage following drug treatment, but it did not alter the radiation-resistant phenotype of these cells. In contrast to the anticancer drugs, IR failed to induc…
Abstract 4662: Shikonin causes cancer cell death by inducing mitochondrial dysfunction
2012
Abstract Shikonin, a naturally occurring napthoquinone, has been used in herbal formulations for the treatment of several inflammatory diseases in Traditional Chinese Medicine since decades. In recent studies, shikonin revealed remarkable anticancer activities and thereby is a promising candidate for cancer chemotherapy. However, the underlying cellular mechanisms and targets of shikonin are still unknown. Here, we showed that shikonin indeed exhibits strong cytotoxic effects on a panel of 15 different cancer cell lines also containing multi-drug resistant cells. The strongest effects were obtained on U937 leukemia cells. To better understand the underlying mechanisms, we performed a whole …
Ultraviolet light-induced DNA damage triggers apoptosis in nucleotide excision repair-deficient cells via Bcl-2 decline and caspase-3/-8 activation.
2001
Ultraviolet (UV) light is a potent mutagenic and genotoxic agent. Whereas DNA damage induced by UV light is known to be responsible for UV-induced genotoxicity, its role in triggering apoptosis is still unclear. We addressed this issue by comparing nucleotide excision repair (NER) deficient 27-1 and 43-3B Chinese hamster (CHO) cells with the corresponding wild-type and ERCC-1 complemented cells. It is shown that NER deficient cells are dramatically hypersensitive to UV-C induced apoptosis, indicating that DNA damage is the major stimulus for the apoptotic response. Apoptosis triggered by UV-C induced DNA damage is related to caspase- and proteosome-dependent degradation of Bcl-2 protein. Th…
The dual PI3K/mTOR inhibitor PKI-587 enhances sensitivity to cetuximab in EGFR-resistant human head and neck cancer models
2014
Background:Cetuximab is the only targeted agent approved for the treatment of head and neck squamous cell carcinomas (HNSCC), but low response rates and disease progression are frequently reported. As the phosphoinositide 3-kinase (PI3K) and the mammalian target of rapamycin (mTOR) pathways have an important role in the pathogenesis of HNSCC, we investigated their involvement in cetuximab resistance.Methods:Different human squamous cancer cell lines sensitive or resistant to cetuximab were tested for the dual PI3K/mTOR inhibitor PF-05212384 (PKI-587), alone and in combination, both in vitro and in vivo.Results:Treatment with PKI-587 enhances sensitivity to cetuximab in vitro, even in the co…
Resveratrol-mediated apoptosis of hodgkin lymphoma cells involves SIRT1 inhibition and FOXO3a hyperacetylation
2012
Resveratrol (RSV), a plant-derived stilbene, induces cell death in Hodgkin lymphoma (HL)-derived L-428 cells in a dose-dependent manner (IC50 = 27 μM, trypan blue exclusion assay). At a lower range (25 μM), RSV treatment for 48 hr causes arrest in the S-phase of the cell cycle, while at a higher concentration range (50 μM), apoptosis can be detected, with activation of caspase-3. The histone/protein deacetylase SIRT1 has been described as a putative target of RSV action in other model systems, even though its role in cancer cells is still controversial. Here we show that RSV, at both concentration ranges, leads to a marked increase in p53, while a decrease of SIRT1 expression level, as well…