Myricetin treatment induces apoptosis in canine osteosarcoma cells by inducing DNA fragmentation, disrupting redox homeostasis, and mediating loss of mitochondrial membrane potential

2018 ◽  
Vol 233 (9) ◽  
pp. 7457-7466 ◽  
Author(s):  
Hahyun Park ◽  
Sunwoo Park ◽  
Fuller W. Bazer ◽  
Whasun Lim ◽  
Gwonhwa Song
Keyword(s):  
Membrane Potential ◽  
Dna Fragmentation ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Redox Homeostasis ◽  
Osteosarcoma Cells ◽  
Canine Osteosarcoma

scholarly journals Differential activation of Fas (CD95) mediated apoptosis by apple procyanidins in human colon cancer cells SW480 and their derived metastatic cells SW620

2011 ◽  
pp. 166-176
Author(s):  
María Elena Maldonado-Celis ◽  
Souad Bousserouel ◽  
Francine Gossé ◽  
Annelise Lobstein ◽  
Francis Raul
Keyword(s):  
Membrane Potential ◽  
Dna Fragmentation ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Human Colon ◽  
Apoptotic Pathway ◽  
Fas Receptor ◽  
Metastatic Cells ◽  
Sw480 Cells ◽  
Sw620 Cells

Introduction: We investigated the effects of apple procyanidins (Pcy), oligomers of catechins and epicatechins on Fas receptor expression and function in human colon adenocarcinoma cells (SW480) and in their derived metastatic cells (SW620). Methods: Pcy were characterized by reverse-phase HPLC. Cell death, Fas proteins, DNA fragmentation, and mitochondrial membrane potential were analyzed by flow cytometry. Fas mRNA was analyzed by RT-PCR in real time. Results: Pcy up-regulated the expression of the Fas receptor at the cell surface of both cell lines but activated Fas gene transcription only in SW620 cells. In SW480 cells, Pcy combined with Fas agonist CH-11 enhanced Fas-mediated apoptosis involving the loss of mitochondrial membrane potential and DNA fragmentation, which were abrogated by the antagonist antibody of Fas receptor, the anti-Fas ZB4. On the contrary, in SW620 cells, CH-11 was not able to enhance Pcy-triggered apoptosis indicating that Fas receptor-mediated apoptosis was not activated in these cells despite an up-regulation of Fas receptor gene expression. However, it was observed in SW620 cells that Pcy activated the Fas receptor-mediated apoptotic pathway after a specific blockage of TRAIL-death DR4/DR5 receptors. Conclusions: The present data showed that Pcy were able to activate the Fas receptor apoptotic pathway in SW480 cells and favored a cross-talk between TRAIL and Fas receptors in SW620 cells because specific blocking of TRAIL death receptors favored activation of the Fas receptor-mediated apoptosis. These important data may allow the emergence of new therapeutic protocols targeting death receptors against resistant metastatic cells.

114 Omega-3-enriched diet improves fertilization competence of cryopreserved sperm

2020 ◽  
Vol 32 (2) ◽  
pp. 184
Author(s):  
D. Kalo ◽  
D. Reches ◽  
A. Komsky-Elbaz ◽  
U. Moallem ◽  
Y. Zeron ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Dna Fragmentation ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Semen Quality ◽  
Sperm Quality ◽  
Fatty Acid Content ◽  
Moderate Increase ◽  
Omega 3 ◽  
Feeding Trial

Intensive reproductive management in dairy herds is mostly based on AI using high-merit bulls. Therefore, semen quality of bulls is of high importance. An association between semen quality and fatty acid content in feed has been suggested. Accordingly, the aim of this study was to examine the effect of omega-3 supplementation on sperm traits and fertilization competence. Fifteen Israeli Holstein bulls were assigned to three experimental groups. Bulls were fed over 13 weeks with a standard ration top-dressed with encapsulated-fat supplementation-fish oil (FO) or flaxseed oil (FLX; i.e. omega-3 sources), or saturated fatty acids (SFA, control). Ejaculates were collected before initiation of the study, during the feeding trial, and 1 month after feeding trial. Ejaculates were treated according to the routine procedure of the Israeli AI centre (Sion Ltd.), frozen, and stored in straws. Frozen-thawed samples were subjected to “swim-up” procedure, and spermatozoon viability, mitochondrial membrane potential, reactive oxygen species (ROS) level, acrosome membrane integrity, and DNA fragmentation were evaluated via flow cytometry, using sperm-specific kits (EasyCyte, IMV Technologies). Feeding with FO, FLX, or SFA did not affect the viability or mitochondrial membrane potential of sperm collected before, during, or after the feeding trial. On the other hand, a reduced proportion of sperm with ROS expression was recorded in the FLX samples compared to the SFA sample at the end of the feeding trial (42.2±1.2 vs. 47.3±4.3%, respectively; P<0.05) and one month later (36.3±2.2 vs. 41.6±4.6%, respectively; P<0.05). A low proportion of sperm with damaged acrosomal membrane was observed in both FLX and FO samples compared with SFA at the end of the feeding trial (48.8±3.4 and 41.7±2.7 vs. 59.8±3.4%, respectively; P<0.05). The proportion of sperm with fragmented DNA was lower in the FLX group than in the SFA group, collected one month after the end of the feeding trial (2.3±0.6 vs. 5.4±1.2%, respectively; P<0.05). To examine fertilization competence, oocytes were aspirated from ovaries collected from a local abattoir, then matured (n=216; 3 replicates) and fertilized invitro with a pool of samples from each group, collected one month after the end of the feeding trial (n=5 samples per group). The proportions of 2- to 4-cell-stage embryos and of blastocysts were determined 42h and 8 days after fertilization, respectively. Although the proportion of cleaved embryos did not differ between groups, a higher blastocyst formation rate was recorded in the FLX group (P<0.05), and a moderate increase was noted in the FO group, relative to the SFA group (28.1±4.4, 19.1±2.6, and 11.9±3.4%, respectively). Results imply that feeding bulls with omega-3 originating from FLX improves sperm quality, most likely due to improved redox status and decreased DNA fragmentation. This nutritional approach seems to be an effective tool for improving bull fertility competence. Nevertheless, invivo examination is required.

scholarly journals Platelet-activating factor-induced apoptosis is blocked by Bcl-2 in rat intestinal epithelial cells

2004 ◽  
Vol 286 (2) ◽  
pp. G340-G350 ◽  
Author(s):  
Jing Lu ◽  
Michael S. Caplan ◽  
Anita P. Saraf ◽  
Dan Li ◽  
Luba Adler ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Epithelial Cells ◽  
Dna Fragmentation ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Caspase 3 ◽  
Intestinal Epithelial Cells ◽  
Regulatory Gene ◽  
Mucosal Injury ◽  
Intestinal Epithelial

Plateletactivating factor (PAF) is a key mediator in pathogenesis of inflammatory bowel diseases (IBDs) but mechanisms of PAF-induced mucosal injury are poorly understood. To determine whether apoptosis and the Bcl-2-family of apoptosis regulatory gene products play a role in PAF-induced mucosal injury, we stably and conditionally overexpressed bcl-2 in rat small intestinal epithelial cells-6 under the control of a lactose-inducible promoter. Western blot analysis and immuno-histochemistry were used to verify inducible Bcl-2 and to analyze Bcl-2 and a proapoptotic member of the Bcl-2 family, Bax, subcellular distribution. DNA fragmentation was quantified by ELISA, caspase activity was measured by using fluorogenic peptide substrates, and mitochondrial membrane potential was assayed by 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylbenzimidazolylcarbocyanine iodide (JC-1) and fluorescence digital imaging. Bcl-2 expression was highly inducible by lactose analog isopropyl-β-d-thiogalactoside (IPTG) and was localized predominantly to mitochondria. In the absence of bcl-2 overexpression and after treatment with PAF, Bax translocated to mitochondria, and mitochondrial membrane potential collapsed within 1 h, followed by caspase-3 activation, which peaked at 6 h with an ensuing DNA fragmentation maximizing at 18 h. After IPTG-induction of bcl-2 expression, PAF failed to induce DNA fragmentation, caspase-3 activation, Bax translocation, or a collapse of mitochondrial membrane potential. These data are the first to show that PAF can activate apoptotic machinery in enterocytes via a mechanism involving Bax translocation and collapse of mitochondrial membrane potential and that both of these events are under control by bcl-2 expression levels. A better understanding of the role of PAF and Bcl-2 family of apoptosis regulators in epithelial cell death might aid design of better therapeutic or preventive strategies for IBDs.

c-Jun N-Terminal Kinase Inhibition Induces Mitochondrial Oxidative Stress and Decreases Survival in Human Neural Stem Progenitors

2018 ◽  
Vol 40 (4) ◽  
pp. 312-324
Author(s):  
Neha Sharma ◽  
Lisamarie Moore ◽  
Shravanthi Chidambaram ◽  
Nicholas W. Colangelo ◽  
Sonia M. de Toledo ◽  
...  
Keyword(s):  
Stem Cells ◽  
Membrane Potential ◽  
Neural Stem Cells ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Redox Homeostasis ◽  
Survivin Expression ◽  
Cell Functions ◽  
Brain Functions ◽  
Redox Environment

Neural stem cells are attracting enormous attention in regenerative medicine due to their ability to self-renew and differentiate into the cell lineages that constitute the central nervous system. However, little is known about the mechanism underlying the regulation of their redox environment, which is essential for homeostatic cellular functions. The redox-modulated c-Jun N-terminal kinases (JNK) are a molecular switch in stress signal transduction and are involved in numerous brain functions. Using a selective but broad-spectrum inhibitor of JNK 1/2/3, we investigated the role of JNK in regulating the levels of reactive oxygen species in mitochondria, mitochondrial membrane potential, viability, proliferation and lineage alterations in human H9-derived neural stem/progenitor cells (NSPs). Relative to diluent control, incubation of the NSPs for 24 h with SP600125, an anthrapyrazolone inhibitor of JNK, resulted in increased abundance of mitochondrial superoxide radicals (p < 0.05), concomitant with decreases in mitochondrial membrane potential (p < 0.001), while maintaining a consistent and stable mitochondrial mass. Whereas H9-derived NSPs collectively express Nestin, a marker for neural stem cells, a panel of cell surface markers analyzed by flow cytometry revealed that they are a heterogeneous population that sustains this diversity after JNK inhibition. In addition, the levels of nuclear forkhead homeobox type O3a (FoxO3a), a regulator of redox homeostasis, decreased, which was associated with a decrease in overall cell viability as measured by Annexin V staining (p < 0.001), and supported by an increased level of cleaved Poly-ADP-ribose polymerase and decreased survivin expression. However, staining with the proliferation marker, Ki67, revealed the presence of a significant percentage of proliferating cells in the treated population. Together, the results support a role for JNK in the redox-homeostasis and fate of NSPs. Identifying regulators of the cellular redox environment will enhance our understanding of the mechanisms that modulate neural stem cell functions and optimize therapeutic applications targeting JNK.

scholarly journals Ovarian fragment sizes affect viability and morphology of preantral follicles during storage at 4°C

Reproduction ◽  
2017 ◽  
Vol 153 (5) ◽  
pp. 577-587 ◽  
Author(s):  
G D A Gastal ◽  
B G Alves ◽  
K A Alves ◽  
M E M Souza ◽  
A D Vieira ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Dna Fragmentation ◽  
Cell Density ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Stromal Cell ◽  
Ovarian Tissue ◽  
Ovarian Tissue Cryopreservation ◽  
Preantral Follicles ◽  
Whole Ovary

The method of transportation and the conditions imposed on the ovarian tissue are pivotal aspects for the success of ovarian tissue cryopreservation (OTC). The aim of this study was to evaluate the effect of the size of the ovarian tissue (e.g. whole ovary, biopsy size and transplant size) during different times of storage (0, 6, 12 and 24 h) on the structural integrity of equine ovarian tissue transported at 4°C. Eighteen pairs of ovaries from young mares (<10 years old) were harvested in a slaughterhouse and processed to simulate the fragment sizes (biopsy and transplant size groups) or kept intact (whole ovary group) and stored at 4°C for up to 24 h in α-MEM-enriched solution. The effect of the size of the ovarian tissue was observed on the morphology of preantral follicles, stromal cell density, DNA fragmentation and mitochondrial membrane potential. The results showed that (i) biopsy size fragments had more morphologically normal preantral follicles after 24 h of storage at 4°C; (ii) mitochondrial membrane potential was the lowest during each storage time when the whole ovary was used; (iii) DNA fragmentation rate in the ovarian cells of all sizes of fragments increased as storage was prolonged and (iv) transplant size fragments had increased stromal cell density during storage at cool temperature. In conclusion, the biopsy size fragment was the best to preserve follicle morphology for long storage (24 h); however, transportation/storage should be prior determined according to the distance (time of transportation) between patient and reproduction centers/clinics.

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