Spermatocyte apoptosis, which involves both intrinsic and extrinsic pathways, explains the sterility of Graomys griseoflavus × Graomys centralis male hybrids

2010 ◽  
Vol 22 (2) ◽  
pp. 478 ◽  
Author(s):  
Valeria Rodriguez ◽  
Gabriela Diaz de Barboza ◽  
Ruben Ponce ◽  
Valeria Merico ◽  
Silvia Garagna ◽  
...  

Spermatogenic impairment and the apoptotic pathways involved in establishing sterility of male hybrids obtained from crossing Graomys griseoflavus females with Graomys centralis males were studied. Testes from G. centralis, G. griseoflavus and hybrids were compared at different ages. Terminal transferase-mediated dUTP nick-end labelling assay (TUNEL), Fas, Bax and cytochrome c labelling were used for apoptosis evaluation, and calbindin D28k staining as an anti-apoptotic molecule. In 1-month-old animals, spermatocytes were positive for all apoptotic markers, but moderate TUNEL (+) spermatocyte frequency was only found in G. centralis. At subsequent ages, the apoptotic markers were downregulated in testes from parental cytotypes, but not in hybrid testes. TUNEL (+) spermatocytes were present at 78% and 44% per tubule cross-section in 2- and 3-month-old hybrid animals, respectively. Pachytene spermatocyte death in adult hybrids occurs via apoptosis, as revealed by high caspase-3 expression. Calbindin was highly expressed in spermatocytes of adult hybrids, in which massive cell death occurs via apoptosis. Calbindin co-localisation with TUNEL or Fas, Bax and cytochrome c was very limited, suggesting an inverse regulation of calbindin and apoptotic markers. Hybrid sterility is due to breakdown of spermatogenesis at the pachytene spermatocyte stage. Both extrinsic and intrinsic pathways are involved in apoptosis of spermatocytes, which are the most sensitive cell type to apoptotic stimuli.

2017 ◽  
Vol 17 (1) ◽  
pp. 330-338 ◽  
Author(s):  
Huiqun Fu ◽  
Fenghua Li ◽  
Sebastian Thomas ◽  
Zhongjin Yang

AbstractBackground and aimsDysfunction of GABAergic inhibitory controls contributes to the development of neuropathic pain. We examined our hypotheses that (1) chronic constriction injury (CCI)-induced neuropathic pain is associated with increased spinal GABAergic neuron apoptosis, and (2) hyperbaric oxygen therapy (HBO) alleviates CCI-induced neuropathic pain by inhibiting GABAergic neuron apoptosis.MethodsMale rats were randomized into 3 groups: CCI, CCI+HBO and the control group (SHAM). Mechanical allodynia was tested daily following CCI procedure. HBO rats were treated at 2.4 atmospheres absolute (ATA) for 60 min once per day. The rats were euthanized and the spinal cord harvested on day 8 and 14 post-CCI. Detection of GABAergic cells and apoptosis was performed. The percentages of double positive stained cells (NeuN/GABA), cleaved caspase-3 or Cytochrome C in total GABAergic cells or in total NeuN positive cells were calculated.ResultsHBO significantly alleviated mechanical allodynia. CCI-induced neuropathic pain was associated with significantly increased spinal apoptotic GABA-positive neurons. HBO considerably decreased these spinal apoptotic cells. Cytochrome-C-positive neurons and cleaved caspase-3-positive neurons were also significantly higher in CCI rats. HBO significantly decreased these positive cells. Caspase-3 mRNA was also significantly higher in CCI rats. HBO reduced mRNA expression of caspase-3.ConclusionsCCI-induced neuropathic pain was associated with increased apoptotic GABAergic neurons induced by activation of key proteins of mitochondrial apoptotic pathways in the dorsal horn of the spinal cord. HBO alleviated CCI-induced neuropathic pain and reduced GABAergic neuron apoptosis. The beneficial effect of HBO may be via its inhibitory role in CCI-induced GABAergic neuron apoptosis by suppressing mitochondrial apoptotic pathways in the spinal cord.ImplicationsIncreased apoptotic GABAergic neurons induced by activation of key proteins of mitochondrial apoptotic pathways in the dorsal horn of the spinal cord is critical in CCI-induced neuropathic pain. The inhibitory role of HBO in GABAergic neuron apoptosis suppresses ongoing neuropathic pain.


2005 ◽  
Vol 15 (3) ◽  
pp. 523-528 ◽  
Author(s):  
M. Di Paola ◽  
G. Loverro ◽  
A. M. Caringella ◽  
G. Cormio ◽  
L. Selvaggi

Under normal conditions, in human endometrium, apoptotic and antiapoptotic factors play an important role in tissue homeostasis. Abnormalities of apoptosis, a process implicated in several events in the reproductive organs, may contribute to neoplastic transformation. The present study aimed to investigate the involvement of both the receptorial and the mitochondrial pathways of apoptosis in normal endometrium and in endometrial carcinoma, by measuring caspase-3 and caspase-8 activities and cytosolic cytochrome c levels. Twelve endometrial carcinomas and nine normal endometrial specimens (four in mild proliferative phase, five in late secretory phase) were included in this study. Cytosolic fractions, obtained by differential centrifugation of tissue homogenates, were analyzed for caspase-3 and caspase-8 activities, as well as for cytochrome c content. Caspase-8 activity in normal secretory phase endometrium was higher than that in the proliferative phase and in the endometrial carcinoma. Moreover, higher cytochrome c levels were detected in endometrial carcinoma with respect to normal secretive endometrium. No significant differences were found in caspase-3 activity between normal and pathologic endometrium. The results obtained suggest that in normal endometrium, apoptosis takes place through the activation of both receptorial and mitochondrial pathways. Defects in both these pathways may contribute to the development of endometrial carcinoma.


2019 ◽  
Vol 19 (9) ◽  
pp. 673-682 ◽  
Author(s):  
Panpan Chang ◽  
Yuzi Tian ◽  
Aaron M. Williams ◽  
Umar F. Bhatti ◽  
Baoling Liu ◽  
...  

Background: Histone deacetylase (HDAC) 6 inhibitors have demonstrated significant protective effects in traumatic injuries. However, their roles in neuroprotection and underlying mechanisms are poorly understood. This study sought to investigate the neuroprotective effects of Tubastatin A (Tub-A), an HDAC6 inhibitor, during oxygenglucose deprivation (OGD) in HT22 hippocampal cells. Methods: HT22 hippocampal cells were exposed to OGD. Cell viability and cytotoxicity were assessed by cell counting kit-8 (CCK-8) and lactate dehydrogenase (LDH) release assay. Cellular apoptosis was assessed by Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Mitochondria membrane potential was detected using JC-1 dye. Expressions of acetylated α-tubulin, α-tubulin, cytochrome c, VDAC, Bax, Bcl- 2, cleaved caspase 3, phosphorylated Akt, Akt, phosphorylated GSK3β and GSK3β were analyzed by Western blot analysis. Results: Tub-A induced acetylation of α-tubulin, demonstrating appropriate efficacy. Tub-A significantly increased cell viability and attenuated LDH release after exposure to OGD. Furthermore, Tub-A treatment blunted the increase in TUNEL-positive cells following OGD and preserved the mitochondrial membrane potential. Tub-A also attenuated the release of cytochrome c from the mitochondria into the cytoplasm and suppressed the ratio of Bax/Bcl-2 and cleaved caspase 3. This was mediated, in part, by the increased phosphorylation of Akt and GSK3β signaling pathways. Conclusion: HDAC 6 inhibition, using Tub-A, protects against OGD-induced injury in HT22 cells by modulating Akt/GSK3β signaling and inhibiting mitochondria-mediated apoptosis.


2020 ◽  
Vol 20 (4) ◽  
pp. 486-494
Author(s):  
Mohamed A. El-Desouky ◽  
Abdelgawad A. Fahmi ◽  
Ibrahim Y. Abdelkader ◽  
Karima M. Nasraldin

Background: Amygdalin (Vitamin B-17) is a naturally occurring vitamin found in the seeds of the fruits of Prunus Rosacea family including apricot, bitter almond, cherry, and peach. Objective: The purpose of this study was to examine the effect of amygdalin with and without zinc on hepatocellular carcinoma (HepG2) cell line. Methods: MTT assay was used to evaluate the cytotoxicity of amygdalin without zinc, amygdalin + 20μmol zinc, and amygdalin + 800μmol zinc on HepG2 cell lines. The cell cycle distribution assay was determined by flow cytometry. Apoptosis was confirmed by Annexin V-FITC/PI staining assay. Moreover, the pathway of apoptosis was determined by the percentage of change in the mean levels of P53, Bcl2, Bax, cytochrome c, and caspase-3. Results: Amygdalin without zinc showed strong anti-HepG2 activity. Furthermore, HepG2 cell lines treatment with amygdalin + 20μmol zinc and amygdalin + 800μmol zinc showed a highly significant apoptotic effect than the effect of amygdalin without zinc. Amygdalin treatment induced cell cycle arrest at G2/M and increased the levels of P53, Bax, cytochrome c, and caspase-3 significantly, while it decreased the level of anti-apoptotic Bcl2. Conclusion: Amygdalin is a natural anti-cancer agent, which can be used for the treatment of hepatocellular carcinoma. It promotes apoptosis via the intrinsic cell death pathway (the mitochondria-initiated pathway) and cell cycle arrest at G/M. The potency of amygdalin in HepG2 treatment increased significantly by the addition of zinc.


Plants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 182 ◽  
Author(s):  
Massimo Malerba ◽  
Raffaella Cerana

Fusicoccin (FC) is a well-known phytotoxin able to induce in Acer pseudoplatanus L. (sycamore) cultured cells, a set of responses similar to those induced by stress conditions. In this work, the possible involvement of peroxynitrite (ONOO−) in FC-induced stress responses was studied measuring both in the presence and in the absence of 2,6,8-trihydroxypurine (urate), a specific ONOO− scavenger: (1) cell death; (2) specific DNA fragmentation; (3) lipid peroxidation; (4) production of RNS and ROS; (5) activity of caspase-3-like proteases; and (6) release of cytochrome c from mitochondria, variations in the levels of molecular chaperones Hsp90 in the mitochondria and Hsp70 BiP in the endoplasmic reticulum (ER), and of regulatory 14-3-3 proteins in the cytosol. The obtained results indicate a role for ONOO− in the FC-induced responses. In particular, ONOO− seems involved in a PCD form showing apoptotic features such as specific DNA fragmentation, caspase-3-like protease activity, and cytochrome c release from mitochondria.


2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Zhenhua Liu ◽  
Liangbin Gao ◽  
Peng Wang ◽  
Zhongyu Xie ◽  
Shuizhong Cen ◽  
...  

Ankylosing spondylitis (AS) is an autoimmune disease with unknown etiology. Dysregulated mesenchymal stem cells (MSCs) apoptosis may contribute to the pathogenesis of autoimmune diseases. However, apoptosis of MSCs from patients with AS (ASMSCs) has not been investigated yet. The present study aims to assess the apoptosis of bone marrow-derived ASMSCs and to investigate the underlying mechanisms of altered ASMSCs apoptosis. We successfully induced the apoptosis of ASMSCs and MSCs from healthy donors (HDMSCs) using the combination of tumor necrosis factor alpha (TNF-α) and cycloheximide (CHX). We found that ASMSCs treated with TNF-αand CHX showed higher apoptosis levels compared to HDMSCs. During apoptosis, ASMSCs expressed significantly more TRAIL-R2, which activated both the death receptor pathway and mitochondria pathway by increasing the expression of FADD, cleaved caspase-8, cytosolic cytochrome C, and cleaved caspase-3. Inhibiting TRAIL-R2 expression using shRNA eliminated the apoptosis differences between HDMSCs and ASMSCs by partially reducing ASMSCs apoptosis but minimally affecting that of HDMSCs. Furthermore, the expression of FADD, cleaved caspase-8, cytosolic cytochrome C, and cleaved caspase-3 were comparable between HDMSCs and ASMSCs after TRAIL-R2 inhibition. These results indicated that increased TRAIL-R2 expression results in enhanced ASMSCs apoptosis and may contribute to AS pathogenesis.


2018 ◽  
Vol 47 (1-3) ◽  
pp. 270-276
Author(s):  
Grazia Maria Virzì ◽  
Chiara Borga ◽  
Chiara Pasqualin ◽  
Silvia Pastori ◽  
Alessandra Brocca ◽  
...  

Background: Sepsis is a life-threatening condition often associated with a high incidence of multiple organs injury. Several papers suggested the immune response by itself, with the production of humoral inflammatory mediators, is crucial in determining organ injury. However, little is known of how sepsis directly induces organ injury at the cellular levels. To assess this point, we set up an in vitro study to investigate the response of renal tubular cells (RTCs), monocytes (U937) and hepatocytes (HepG2) after 24 h-incubation with septic patients’ plasma. Methods: We enrolled 26 septic patients (“test” group). We evaluated cell viability, apoptosis and necrosis by flow cytometer. Caspase-3,-8,-9 and cytochrome-c concentrations have been analyzed using the Human enzyme-linked immunosorbent assay kit. Results: We found that a decrease of cell viability in all cell lines tested was associated to the increase of apoptosis in RTCs and U937 (p < 0.0001) and increase of necrosis in HepG2 (p < 0.5). The increase of apoptosis in RTCs and U937 cells was confirmed by higher levels of caspase-3 (p < 0.0001). We showed that apoptosis in both RTCs and U937 was triggered by the activation of the intrinsic pathway, as caspase-9 and cytochrome-c levels significantly increased (p < 0.0001), while caspase-8 did not change. This assumption was strengthened by the significant correlation of caspase-9 with both cytochrome-c (r = 0.73 for RTCs and r = 0.69 for U937) and caspase-3 (r = 0.69 for RTCs and r = 0.63 for U937). Conclusion: Humoral mediators in septic patients’ plasma induce apoptosis. This fact suggests that apoptosis inhibitors should be investigated as future strategy to reduce sepsis-induced organ damages.


2017 ◽  
Vol 20 (2) ◽  
pp. 329-338 ◽  
Author(s):  
J. Sokołowska ◽  
K. Urbańska

AbstractSurvivin regulates cell cycle and mitosis and has antiapoptotic properties. Because of its dual function survivin has been the subject of much research focusing on its role in tumorigenesis and the relationship between survivin expression and apoptotic and/or proliferative activity in many types of human tumor including non-Hodgkin’s Lymphomas. Such studies have not been conducted in canine lymphomas. The aim of this study was to evaluate the expression of survivin in canine lymphomas of low (5/25) and high (20/25) grades in relation to apoptotic markers (apoptotic index and index of caspase-3). Survivin was found in all examined lymphomas. Most tumors (18/25) showed survivin expression in 10%-25% of positive cells. Only in single cases was lower (0-10% positive cells, 1/25) or higher (25%-50% and >50% positive cells, 5/25 and 1/25, respectively) survivin expression. No significant differences between mean values of either index of survivin or apoptotic index was found between low and high grade lymphomas. However, such a difference among lymphoma grades was shown regarding the caspase-3 index. No correlation between the survivin index and either the apoptotic index or caspase-3 index was found, irrespective of the method of quantification: in whole specimens or in areas of low and high survivin expression. Positive correlation was consistently noted only between both apoptotic markers. The results indicate that survivin is commonly expressed in canine lymphomas. It seems that survivin does not exhibit anti-apoptotic activity in canine lymphomas. Lack of correlation between survivin expression and apoptotic markers could indicate its potential role in cell cycle activation in lymphoma cells.


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