Bax, Caspase-2, and Caspase-3 Are Required for Ovarian Follicle Loss Caused by 4-Vinylcyclohexene Diepoxide Exposure of Female Mice in Vivo

The enterobacterial pathogen Salmonella induces phagocyte apoptosis in vitro and in vivo. These bacteria use a specialized type III secretion system to export a virulence factor, SipB, which directly activates the host's apoptotic machinery by targeting caspase-1. Caspase-1 is not involved in most apoptotic processes but plays a major role in cytokine maturation. We show that caspase-1–deficient macrophages undergo apoptosis within 4–6 h of infection with invasive bacteria. This process requires SipB, implying that this protein can initiate the apoptotic machinery by regulating components distinct from caspase-1. Invasive Salmonella typhimurium targets caspase-2 simultaneously with, but independently of, caspase-1. Besides caspase-2, the caspase-1–independent pathway involves the activation of caspase-3, -6, and -8 and the release of cytochrome c from mitochondria, none of which occurs during caspase-1–dependent apoptosis. By using caspase-2 knockout macrophages and chemical inhibition, we establish a role for caspase-2 in both caspase-1–dependent and –independent apoptosis. Particularly, activation of caspase-1 during fast Salmonella-induced apoptosis partially relies on caspase-2. The ability of Salmonella to induce caspase-1–independent macrophage apoptosis may play a role in situations in which activation of this protease is either prevented or uncoupled from the induction of apoptosis.

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ABCC4 is a PGE2 Efflux Transporter in The Ovarian Follicle: A Mediator of Ovulation and A Potential Non-Hormonal Contraceptive Target

10.21203/rs.3.rs-142822/v1 ◽

2021 ◽

Author(s):

Gil Yerushalmi ◽

Bat-el Shuraki ◽

Yuval Yung ◽

Ettie Maman ◽

Micha Baum ◽

...

Keyword(s):

Ovarian Follicle ◽

Hormonal Contraception ◽

Hormonal Contraceptive ◽

Efflux Transporter ◽

Extracellular Concentration ◽

Female Mice ◽

And Control ◽

Ovulatory Process

Abstract The role of Prostaglandins (PGs) in the ovulatory process is known. However, the role of the ATP binding cassette subfamily C member 4 (ABCC4), transmembrane PG carrier protein, in ovulation remains unknown. We report herein that ABCC4 expression is significantly upregulated in preovulatory human granulosa cells (GCs). We found that PGE2 efflux in cultured human GCs is mediated by ABCC4 thus regulating its extracellular concentration. The ABCC4 inhibitor Probenecid demonstrated effective blocking of ovulation and affects key ovulatory genes in female mice in vivo. We postulate that the reduction of PGE2 efflux caused by the inhibition of ABCC4 activity in GCs decreases the extracellular concentration of PGE2 and its ovulatory effect. Treatment of female mice with low dose of Probenecid as well as with the PTGS inhibitor Indomethacin or Meloxicam synergistically blocks ovulation. These results support the hypothesis that ABCC4 has an important role in ovulation and might be a potential target for non-hormonal contraception, especially in combination with PGE2 synthesis inhibitors. These findings may fill the gap in understanding the role of ABCC4 in PGE2 signaling, enhance the understanding of ovulatory disorders, and facilitate the treatment and control of fertility.

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HIF-1α Protects Granulosa Cells From Hypoxia-Induced Apoptosis During Follicular Development by Inducing Autophagy

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.631016 ◽

2021 ◽

Vol 9 ◽

Author(s):

Zonghao Tang ◽

Renfeng Xu ◽

Zhenghong Zhang ◽

Congjian Shi ◽

Yan Zhang ◽

...

Keyword(s):

Granulosa Cells ◽

Mammalian Cells ◽

Caspase 3 ◽

Ovarian Follicle ◽

Hypoxia Inducible Factor ◽

Follicular Development ◽

B Cell Lymphoma ◽

Underlying Mechanism

Owing to the avascular structure of the ovarian follicle, proliferation of granulosa cells (GCs) and development of follicles occur under hypoxia, which is obviously different from the cell survival requirements of most mammalian cells. We hypothesized that autophagy may exert an inhibitory effect on GC apoptosis. To decipher the underlying mechanism, we constructed a rat follicular development model using pregnant mare serum gonadotropin and a cell culture experiment in hypoxic conditions (3% O2). The present results showed that the autophagy level was obviously increased and was accompanied by the concomitant elevation of hypoxia inducible factor (HIF)-1α and BNIP3 (Bcl-2/adenovirus E1B 19kDa-interacting protein 3) in GCs during follicular development. The levels of Bax (Bcl2-associated X) and Bcl-2 (B-cell lymphoma-2) were increased, while the activation of caspase-3 exhibited no obvious changes during follicular development. However, inhibition of HIF-1α attenuated the increase in Bcl-2 and promoted the increase in Bax and cleaved caspase-3. Furthermore, we observed the downregulation of BNIP3 and the decrease in autophagy after treatment with a specific HIF-1α activity inhibitor (echinomycin), indicating that HIF-1α/BNIP3 was involved in autophagy regulation in GCs in vivo. In an in vitro study, we also found that hypoxia did not obviously promote GC apoptosis, while it significantly enhanced the activation of HIF-1α/BNIP3 and the induction of autophagy. Expectedly, this effect could be reversed by 3-methyladenine (3-MA) treatment. Taken together, these findings demonstrated that hypoxia drives the activation of HIF-1α/BNIP3 signaling, which induces an increase in autophagy, protecting GC from apoptosis during follicular development.

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In vivo ischemic preconditioning by caspase-3 cleavage of poly(ADP-ribose) polymerase-1

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/sj.jcbfm.9591524.0305 ◽

2005 ◽

Vol 25 (1_suppl) ◽

pp. S305-S305

Author(s):

Philippe E Garnier ◽

San Won Suh ◽

Weihai Ying ◽

Raymond A Swanson

Keyword(s):

Ischemic Preconditioning ◽

Caspase 3

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Faculty Opinions recommendation of Chk1 suppresses a caspase-2 apoptotic response to DNA damage that bypasses p53, Bcl-2, and caspase-3.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1109010.568116 ◽

2008 ◽

Author(s):

Sharad Kumar

Keyword(s):

Dna Damage ◽

Caspase 3 ◽

Apoptotic Response ◽

Caspase 2

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Evaluation of the In Vivo Acute Toxicity and In Vitro Hemolytic and Immunomodulatory Activities of the Moringa oleifera Flower Trypsin Inhibitor (MoFTI)

Protein and Peptide Letters ◽

10.2174/0929866527999201113105858 ◽

2020 ◽

Vol 27 ◽

Author(s):

Leydianne Leite de Siqueira Patriota ◽

Dayane Kelly Dias do Nascimento Santos ◽

Bárbara Rafaela da Silva Barros ◽

Lethícia Maria de Souza Aguiar ◽

Yasmym Araújo Silva ◽

...

Keyword(s):

Acute Toxicity ◽

Trypsin Inhibitor ◽

Hemolytic Activity ◽

Moringa Oleifera ◽

Biological Activities ◽

Hematological Parameters ◽

Behavioral Alterations ◽

Female Mice

Background: Protease inhibitors have been isolated from plants and present several biological activities, including immunomod-ulatory action. Objective: This work aimed to evaluate a Moringa oleifera flower trypsin inhibitor (MoFTI) for acute toxicity in mice, hemolytic activity on mice erythrocytes and immunomodulatory effects on mice splenocytes. Methods: The acute toxicity was evaluated using Swiss female mice that received a single dose of the vehicle control or MoFTI (300 mg/kg, i.p.). Behavioral alterations were observed 15–240 min after administration, and survival, weight gain, and water and food consumption were analyzed daily. Organ weights and hematological parameters were analyzed after 14 days. Hemolytic activity of MoFTI was tested using Swiss female mice erythrocytes. Splenocytes obtained from BALB/c mice were cultured in the absence or presence of MoFTI for the evaluation of cell viability and proliferation. Mitochondrial membrane potential (ΔΨm) and reactive oxygen species (ROS) levels were also determined. Furthermore, the culture supernatants were analyzed for the presence of cytokines and nitric oxide (NO). Results: MoFTI did not cause death or any adverse effects on the mice except for abdominal contortions at 15–30 min after administration. MoFTI did not exhibit a significant hemolytic effect. In addition, MoFTI did not induce apoptosis or necrosis in splenocytes and had no effect on cell proliferation. Increases in cytosolic and mitochondrial ROS release, as well as ΔΨm reduction, were observed in MoFTI-treated cells. MoFTI was observed to induce TNF-α, IFN-γ, IL-6, IL-10, and NO release. Conclusion: These results contribute to the ongoing evaluation of the antitumor potential of MoFTI and its effects on other immunological targets.

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BRD4 PROTAC degrader ARV-825 inhibits T-cell acute lymphoblastic leukemia by targeting 'Undruggable' Myc-pathway genes

Cancer Cell International ◽

10.1186/s12935-021-01908-w ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Shuiyan Wu ◽

You Jiang ◽

Yi Hong ◽

Xinran Chu ◽

Zimu Zhang ◽

...

Keyword(s):

Cell Cycle ◽

Cell Proliferation ◽

Acute Lymphoblastic Leukemia ◽

Caspase 3 ◽

Lymphoblastic Leukemia ◽

Rna Seq ◽

Cell Acute Lymphoblastic Leukemia ◽

Bet Protein

Abstract Background T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive disease with a high risk of induction failure and poor outcomes, with relapse due to drug resistance. Recent studies show that bromodomains and extra-terminal (BET) protein inhibitors are promising anti-cancer agents. ARV-825, comprising a BET inhibitor conjugated with cereblon ligand, was recently developed to attenuate the growth of multiple tumors in vitro and in vivo. However, the functional and molecular mechanisms of ARV-825 in T-ALL remain unclear. This study aimed to investigate the therapeutic efficacy and potential mechanism of ARV-825 in T-ALL. Methods Expression of the BRD4 were determined in pediatric T-ALL samples and differential gene expression after ARV-825 treatment was explored by RNA-seq and quantitative reverse transcription-polymerase chain reaction. T-ALL cell viability was measured by CCK8 assay after ARV-825 administration. Cell cycle was analyzed by propidium iodide (PI) staining and apoptosis was assessed by Annexin V/PI staining. BRD4, BRD3 and BRD2 proteins were detected by western blot in cells treated with ARV-825. The effect of ARV-825 on T-ALL cells was analyzed in vivo. The functional and molecular pathways involved in ARV-825 treatment of T-ALL were verified by western blot and chromatin immunoprecipitation (ChIP). Results BRD4 expression was higher in pediatric T-ALL samples compared with T-cells from healthy donors. High BRD4 expression indicated a poor outcome. ARV-825 suppressed cell proliferation in vitro by arresting the cell cycle and inducing apoptosis, with elevated poly-ADP ribose polymerase and cleaved caspase 3. BRD4, BRD3, and BRD2 were degraded in line with reduced cereblon expression in T-ALL cells. ARV-825 had a lower IC50 in T-ALL cells compared with JQ1, dBET1 and OTX015. ARV-825 perturbed the H3K27Ac-Myc pathway and reduced c-Myc protein levels in T-ALL cells according to RNA-seq and ChIP. In the T-ALL xenograft model, ARV-825 significantly reduced tumor growth and led to the dysregulation of Ki67 and cleaved caspase 3. Moreover, ARV-825 inhibited cell proliferation by depleting BET and c-Myc proteins in vitro and in vivo. Conclusions BRD4 indicates a poor prognosis in T-ALL. The BRD4 degrader ARV-825 can effectively suppress the proliferation and promote apoptosis of T-ALL cells via BET protein depletion and c-Myc inhibition, thus providing a new strategy for the treatment of T-ALL.

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miR-146a-5p Promotes Chondrocyte Apoptosis and Inhibits Autophagy of Osteoarthritis by Targeting NUMB

Cartilage ◽

10.1177/19476035211023550 ◽

2021 ◽

pp. 194760352110235

Author(s):

Hongjun Zhang ◽

Wendi Zheng ◽

Du Li ◽

Jia Zheng

Keyword(s):

Caspase 3 ◽

Cartilage Tissue ◽

Luciferase Reporter ◽

Chondrocyte Apoptosis ◽

Knee Cartilage ◽

Before And After ◽

Related Proteins ◽

Human And Mouse

Objective miR-146a-5p was found to be significantly upregulated in cartilage tissue of patients with osteoarthritis (OA). NUMB was shown to be involved in the autophagy regulation process of cells. We aimed to learn whether NUMB was involved in the apoptosis or autophagy process of chondrocytes in OA and related with miR-146a-5p. Methods QRT-PCR was used to detect miR-146a-5p level in 22 OA cartilage tissues and 22 controls. The targets of miR-146a-5p were analyzed using software and the luciferase reporter experiment. The apoptosis and autophagy, and related proteins were detected in chondrocytes treated with miR-146a-5p mimic/inhibitor or pcDNA3.1-NUMB/si-NUMB and IL-1β, respectively. In vivo experiment, intra-articular injection of miR-146a-5p antagomir/NC was administered at the knee of OA male mice before and after model construction. Chondrocyte apoptosis and the expression of apoptosis and autophagy-related proteins were also detected. Results miR-146a-5p was highly expressed in knee cartilage tissue of patients with OA, while NUMB was lowly expressed and negatively regulated by miR-146a-5p. Upregulation of miR-146a-5p can promote cell apoptosis and reduce autophagy of human and mouse chondrocytes by modulating the levels of cleaved caspase-3, cleaved PARP, Bax, Beclin 1, ATG5, p62, LC3-I, and LC3-II. Increasing the low level of NUMB reversed the effects of miR-146a-5p on chondrocyte apoptosis and autophagy. Intra-articular injection of miR-146a-5p antagomir can also reverse the effects of miR-146a-5p on the apoptosis and autophagy of knee joint chondrocytes in OA mice. Conclusion Downregulation of miR-146a-5p suppresses the apoptosis and promotes autophagy of chondrocytes by targeting NUMB in vivo and in vitro.

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