Bcl-2 Research Articles

Hypermethylation of the Gene Body in SRCIN1 Is Involved in Breast Cancer Cell Proliferation and Is a Potential Blood-Based Biomarker for Early Detection and a Poor Prognosis.

Breast cancer is a leading cause of cancer mortality in women worldwide. Using the Infinium MethylationEPIC BeadChip, we analyzed plasma sample methylation to identify the SRCIN1 gene in breast cancer patients. We assessed SRCIN1-related roles and pathways for their biomarker potential. To verify the methylation status, quantitative methylation-specific PCR (qMSP) was performed on genomic DNA and circulating cell-free DNA samples, and mRNA expression analysis was performed using RT‒qPCR. The results were validated in a Western population; for this analysis, the samples included plasma samples from breast cancer patients from the USA and from The Cancer Genome Atlas (TCGA) cohort. To study the SRCIN1 pathway, we conducted cell viability assays, gene manipulation and RNA sequencing. SRCIN1 hypermethylation was identified in 61.8% of breast cancer tissues from Taiwanese patients, exhibiting specificity to this malignancy. Furthermore, its presence correlated significantly with unfavorable 5-year overall survival outcomes. The levels of methylated SRCIN1 in the blood of patients from Taiwan and the USA correlated with the stage of breast cancer. The proportion of patients with high methylation levels increased from 0% in healthy individuals to 63.6% in Stage 0, 80% in Stage I and 82.6% in Stage II, with a sensitivity of 78.5%, an accuracy of 90.3% and a specificity of 100%. SRCIN1 hypermethylation was significantly correlated with increased SRCIN1 mRNA expression (p < 0.001). Knockdown of SRCIN1 decreased the viability of breast cancer cells. SRCIN1 silencing resulted in the downregulation of ESR1, BCL2 and various cyclin protein expressions. SRCIN1 hypermethylation in the blood may serve as a noninvasive biomarker, facilitating early detection and prognosis evaluation, and SRCIN1-targeted therapies could be used in combination regimens for breast cancer patients.

Efficacy and Safety of Asparagusic Acid against Echinococcus multilocularis In Vitro and in a Murine Infection Model.

Alveolar echinococcosis (AE) stands as a perilous zoonotic affliction caused by the larvae of Echinococcus multilocularis. There is an imperative need to explore novel therapeutic agents or lead compounds for the treatment of AE. Asparagusic acid, characterized by its low toxicity and possessing antimicrobial, antioxidant, and anti-parasitic attributes, emerges as a promising candidate. The aim of this study was to investigate the in vivo and in vitro efficacy of asparagusic acid against E. multilocularis. Morphological observations, scanning electron microscopy, ROS assays, mitochondrial membrane potential assays, and Western blot were used to evaluate the in vitro effects of asparagusic acid on protoscoleces. The effects of asparagusic acid on vesicles were assessed via PGI release, γ-GGT release, and transmission electron microscopy observations. CellTiter-Glo assays, Caspase3 activity assays, flow cytometry, and Western blot were used for an evaluation of the effect of asparaginic acid on the proliferation and apoptosis of germinal cells. The in vivo efficacy of asparagusic acid was evaluated in a murine AE model. Asparagusic acid exhibited a pronounced killing effect on the protoscoleces post-treatment. Following an intervention with asparagusic acid, there was an increase in ROS levels and a decline in mitochondrial membrane potential in the protoscolex. Moreover, asparagusic acid treatment resulted in the upregulation of PGI and γ-GGT release in metacestode vesicles, concomitant with the inhibition of germinal cell viability. Furthermore, asparagusic acid led to an enhanced relative expression of Caspase3 in the culture supernatant of both the protoscoleces and germinal cells, accompanied by an increase in the proportion of apoptotic germinal cells. Notably, asparagusic acid induced an augmentation in Bax and Caspase3 protein expression while reducing Bcl2 protein expression in both the protoscoleces and germinal cells. In vitro cytotoxicity assessments demonstrated the low toxicity of asparagusic acid towards normal human hepatocytes and HFF cells. Additionally, in vivo experiments revealed that asparagusic acid administration at doses of 10 mg/kg and 40 mg/kg significantly reduced metacestode wet weight. A histopathological analysis displayed the disruption of the germinal layer structure within lesions post-asparagusic acid treatment, alongside the preservation of laminated layer structures. Transmission electron microscopy further revealed mitochondrial swelling and heightened cell necrosis subsequent to the asparagusic acid treatment. Furthermore, asparagusic acid promoted Caspase3 and Bax protein expression while decreasing Bcl2 protein expression in perilesional tissues. Subsequently, it inhibited the expression of Ki67, MMP2, and MMP9 proteins in the perilesional tissues and curbed the activation of the PI3K/Akt signaling pathway within the lesion-host microenvironmental tissues. Asparagusic acid demonstrated a pronounced killing effect on E. multilocularis, suggesting its potential as a promising therapeutic agent for the management of AE.

Blockage of BCL-XL overcomes venetoclax resistance across BCL2+ lymphoid malignancies irrespective of BIM status

AbstractVenetoclax (VEN), a B-cell lymphoma 2 (BCL2) inhibitor, has a promising single-agent activity in mantle cell lymphoma (MCL), acute lymphoblastic leukemia (ALL), and large BCLs, but remissions were generally short, which call for rational drug combinations. Using a panel of 21 lymphoma and leukemia cell lines and 28 primary samples, we demonstrated strong synergy between VEN and A1155463, a BCL-XL inhibitor. Immunoprecipitation experiments and studies on clones with knockout of expression or transgenic expression of BCL-XL confirmed its key role in mediating inherent and acquired VEN resistance. Of note, the VEN and A1155463 combination was synthetically lethal even in the cell lines with lack of expression of the proapoptotic BCL2L11/BIM and in the derived clones with genetic knockout of BCL2L11/BIM. This is clinically important because BCL2L11/BIM deletion, downregulation, or sequestration results in VEN resistance. Immunoprecipitation experiments further suggested that the proapoptotic effector BAX belongs to principal mediators of the VEN and A1155463 mode of action in the BIM-deficient cells. Lastly, the efficacy of the new proapoptotic combination was confirmed in vivo on a panel of 9 patient–derived lymphoma xenografts models including MCL (n = 3), B-ALL (n = 2), T-ALL (n = 1), and diffuse large BCL (n = 3). Because continuous inhibition of BCL-XL causes thrombocytopenia, we proposed and tested an interrupted 4 days on/3 days off treatment regimen, which retained the desired antitumor synergy with manageable platelet toxicity. The proposed VEN and A1155463 combination represents an innovative chemotherapy-free regimen with significant preclinical activity across diverse BCL2+ hematologic malignancies irrespective of the BCL2L11/BIM status.

Study on the inhibitory and pro-apoptotic effects of different concentrations of total tanshinone alone and in combination with tyrosine kinase inhibitors on human myeloid leukemia cell lines

Objective: To explore the effect and investigate the molecular mechanism of different concentrations of total tanshinones alone and in combination with tyrosine kinase inhibitors (TKIs) on the proliferation inhibition and apoptosis of human myeloid leukemia cell lines. Methods: K562 and Kasumi-1 cell lines were purchased from the Shanghai Cell Bank of the Chinese Academy of Sciences, and the TKIs-resistant strain K562/T315I cell line was constructed in Molecular Medicine Research Center, Beijing Lu Daopei Institute of Hematology. Logarithmic growth phase cells were taken and divided into intervention groups with total tanshinone of 0, 2.19, 4.38, 8.75, 17.50 and 35.00 μg/ml intervention groups, which were inoculated in 96-well plates at a density of 1×104 cells/well and exposed to the drug for 24 h, and a control group treated with dimethyl sulfoxide was also set up simultaneously. All experiments were repeated independently 3-5 times. The proliferative activity of the cells was assessed using the CCK-8 assay, the apoptotic rates were measured by flow cytometry, and the expression levels of apoptosis-regulating proteins Bcl-2 and Bax were analyzed by Western blotting. The cell lines treated and untreated with total tanshinone were subjected to transcriptome sequencing and gene set enrichment analysis to identify differentially expressed genes. Results: The half-inhibitory concentration (IC50) values of 8.75 μg/ml total tanshinone at 24 h for K562, K562/T315I and Kasumi-1 cells were (4.11±0.02), (4.95±0.04) and (3.98±0.01) μg/ml, respectively. When combined with 0.25 μmol/L imatinib, 8.75 μg/ml total tanshinone could enhance the induction of apoptosis effects on K562 and K562/T315I cell lines. After being treated with 4.38, 8.75, and 17.50 μg/ml of total tanshinone for 24 h, compared with the control group, total tanshinone upregulated the expression level of Bax protein, downregulated the expression level of Bcl-2 protein, and decreased the Bcl-2/Bax ratio (all P<0.05). Total tanshinone inhibited the proliferation-related signaling pathway and DNA damage repair pathway of myeloid leukemia cell lines, and activated the signaling pathway that induces apoptosis in leukemia cells. Conclusion: Different concentrations of total tanshinoneinhibites proliferation and promote apoptosis in K562, Kasumi-1 and TKIs-resistant K562/T315I cell lines, and further enhance the anti-leukemic effect when combined with TKIs.

Therapeutic Potential of Silymarin in Mitigating Paclitaxel-Induced Hepatotoxicity and Nephrotoxicity: Insights into Oxidative Stress, Inflammation, and Apoptosis in Rats.

Paclitaxel (PAX) is a widely used chemotherapy drug for various cancer types but often induces significant toxicity in multiple organ systems. Silymarin (SIL), a natural flavonoid, has shown therapeutic potential due to its multiple benefits. To evaluate the therapeutic efficacy of SIL in mitigating liver and kidney damage induced by PAX in rats, focusing on oxidative stress, inflammation, and apoptosis pathways. Experimental animal model. The study included 28 male Wistar rats aged 12-14 weeks weighing 270-300 g. The rats were divided into four groups: control, SIL, PAX, and PAX + SIL, with seven in each group. The rats received intraperitoneal (i.p.) injections at a dose of 2 mg per kilogram of body weight of PAX for 5 successive days, followed by oral gavage with 200 mg/kg body mass of SIL for 10 uninterrupted days. We examined the effect of SIL on specific serum biochemical parameters using an autoanalyzer and rat-specific kits. The spectrophotometric methods was used to investigate oxidative stress indicators in kidney and liver tissues. Aquaporin-2 (AQP-2), B-cell lymphoma-2 (Bcl-2), cysteine aspartate-specific protease-3 (caspase-3), interleukin-6 (IL-6), nuclear factor kappa B (NF-κB), and streptavidin-biotin staining were used to assess immunoreactivity in PAX-induced liver and kidney injury models. SIL treatment significantly reduced serum levels of alanine aminotransferase, aspartate aminotransferase, creatinine, urea, and C-reactive protein, indicating its effectiveness in treating PAX-induced liver and kidney injury. SIL treatment significantly reduced oxidative stress by increasing essential antioxidant parameters, such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione. It also reduced malondialdehyde levels in liver and kidney tissues of SIL-PAX groups (p < 0.05). SIL administration reduced NF-κB, caspase-3, and IL-6 expression while increasing Bcl-2 and AQP2 levels in liver and kidney tissues of rats treated with SIL and PAX (p < 0.05). Our findings indicate the potential of SIL to alleviate PAX-induced liver and kidney damage in rats by reducing oxidative stress, inflammation, and apoptotic processes.

New insights into resveratrol attenuates hepatotoxicity in emamectin benzoate-exposed grass carp (Ctenopharyngodon idella) via NO system/NF-κB signaling pathway

Emamectin benzoate (EMB) is extensively used as a crop protection agent. Overuse of EMB poses a serious threat to the quality of water and non-target organisms in the environment. Resveratrol (RES) is a natural phytoalexin with the function of anti-oxidation and anti-inflammation. Nonetheless, it is unclear whether EMB affects the expression of cytokines and induces autophagy, apoptosis, and necroptosis of hepatocytes (L8824 cell) in grass carp (Ctenopharyngodon idella), and whether RES has an attenuate function in this process. Therefore, we established the L8824 cells model of EMB exposure and treated it with RES. The results showed that compared with the control (CON) group, EMB exposure significantly increased the nitric oxide (NO) content, inducible nitric oxide synthase (iNOS) activity, and the expression of iNOS and phosphorylated nuclear factor kappa B (p-NF-κB) (P < 0.05). In addition, compared with the CON group, the results of flow cytometry and dansylcadaverine (MDC) staining showed a significant increase in apoptosis and autophagy in the EMB-exposed group (P < 0.05) with the activation of the B-cell lymphoma-2 (Bcl-2)/Bcl-2 associated X (Bax)/cysteine-aspartic acid protease 3 (Caspase-3)/cysteine-aspartic acid protease 9 (Caspase-9) pathway and microtubule-associated protein light chain 3 (LC3)/sequestosome 1 (p62)/Beclin1 pathway. EMB exposure significantly increased the mRNA and protein expression of receptor-interacting protein 1 (RIPK1)/receptor-interacting protein 3 (RIPK3)/mixed the lineage kinase domain-like (MLKL) pathway (P < 0.05). Moreover, EMB exposure significantly increased the expression of genes related to immunity (immunoglobulin G (IgG), immunoglobulin M (IgM), and immunoglobulin D (IgD), and antimicrobial peptide-related genes expression including β-defensin and hepcidin) (P < 0.05). The addition of RES significantly diminished autophagy, apoptosis, necroptosis, and immunity-related gene expression by inhibiting iNOS activity, NO content, and the protein expression of iNOS and p-NF-κB. In conclusion, RES attenuated autophagy, apoptosis, and necroptosis in EMB-exposed L8824 cells via suppression of the NO system/NF-κB signaling pathway.

Discovery of the Clinical Candidate Sonrotoclax (BGB-11417), a Highly Potent and Selective Inhibitor for Both WT and G101V Mutant Bcl-2.

The approval of venetoclax, a B-cell lymphoma-2 (Bcl-2) selective inhibitor, for the treatment of chronic lymphocytic leukemia demonstrated that the antiapoptotic protein Bcl-2 is a druggable target for B-cell malignancies. However, venetoclax's limited potency cannot produce a strong, durable clinical benefit in other Bcl-2-mediated malignancies (e.g., diffuse large B-cell lymphomas) and multiple recurrent Bcl-2 mutations (e.g., G101V) have been reported to mediate resistance to venetoclax after long-term treatment. Herein, we described novel Bcl-2 inhibitors with increased potency for both wild-type (WT) and mutant Bcl-2. Comprehensive structure optimization led to the clinical candidate BGB-11417 (compound 12e, sonrotoclax), which exhibits strong in vitro and in vivo inhibitory activity against both WT Bcl-2 and the G101V mutant, as well as excellent selectivity over Bcl-xL without obvious cytochrome P450 inhibition. Currently, BGB-11417 is undergoing phase II/III clinical assessments as monotherapy and combination treatment.

The Comparative Effect of Plasma Exosomes of Young and Old People on the Expression of BCL-2 and BAX Genes in Hematopoietic Stem Cells.

Apoptosis may disrupt differentiation of hematopoietic stem cells (HSCs), which can affect aging. Thus, the main goal of this study was to compare the effect of plasma exosomes from young and old people on the expression of Bcl-2-associated X (BAX) and B-cell lymphoma 2 (BCL-2) genes in the HSCs. Plasma samples were acquired from four elderly adults and four younger adults, referring to Blood Transfusion Organization of Tehran-Iran during August 2022- September 2022.Then, the exosomes of the samples were extracted and analyzed using DLS, TEM, and CD63 surface marker. HSCs were isolated from umbilical cord blood cells. The MTT test was used to assess the viability of exosomes-treated HSCs at doses of 5 and 10 μg/ml. The expression of BAX and BCL-2 genes in the cells was examined using real-time PCR. A one-way analysis of variance (ANOVA) was performed to examine the distinctions among five groups. The viability of HSCs was not affected by the exosomes from young and old people than the control group (P = 0.453). Exosomes from young people (doses 5 and 10 µg/ml) did not have any significant impacts on BAX (P = 0.746, and P = 0.345, respectively) and BCL-2 (P = 0.773, and P = 0.461, respectively) expression in the HSCs compared to the control group. The BAX gene was significantly upregulated and the BCL-2 gene was significantly downregulated after utilizing the exosomes derived from the plasma of elderly individuals (dose 10 µg/ml) compared to the control (P = 0.001, P = 0.002, respectively). The current research shows that aged people's exosomes can increase BAX/ BCL-2 ratio in umbilical cord blood-derived HSCs compared to control and young groups.

DNA methylation by DNMT3a drives endothelial inflammation and death during acute lung injury

Vascular endothelium, the inner most lining of all blood vessels, controls the transport of nutrients, protein, water, and leukocytes across the vessel wall and thereby maintains lung tissue and fluid homeostasis. Damage to endothelial integrity caused by mediagenic, inflammatory, or toxic agents results in pulmonary edema, inflammation, organ failure, and high lethality. A key pathogenic characteristic of vascular injury involves an excessive loss of endothelial cells (EC) accompanied by the generation of inflammatory cytokines. Genome-wide analyses of DNA methylation, the most enduring epigenetic modification of DNA, and its impact on EC transcriptomes and cellular functions, still lack comprehensive understanding. We demonstrate that lipopolysaccharide (LPS) elevated DNA methylation in EC within the lungs, primarily through a mechanism dependent on DNA methyltransferase 3a (DNMT 3a). Mice with endothelial cell-specific deletion of DNMT3a ( EC-DNMT3a−/−) promptly recovered from lung injury, attributed to a reduction of EC death. Furthermore, we observed that the deletion of DNMT3a in EC led to an increase in the expression of the apoptosis inhibitor B-cell lymphoma 2 (BCL2). Collectively, the data implies that inhibiting DNMT3a activity plays a crucial role in reshaping the EC methylome and promoting BCL-2 activity. This, in turn, facilitates the generation of reparative EC and contributes to the resolution of acute lung injury (ALI). These findings offer insights into potential targets for preventing ALI. American Heart Association (AHA) Postdoctoral Fellowship (19POST34450241). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Curcumin protects against cadmium-induced germ cell death in the testis of rats.

Cadmium (Cd) has been shown to disrupt the reproductive system. In this study, we evaluated the protective effects of Curcumin (Cur) against Cd-induced reproductive toxicity. Exploring the role of Cur in Cd-treated rat models. The study demonstrated that Cd treatment impaired the seminiferous epithelium, leading to increased apoptosis of germ cells. Interestingly, pretreatment with Cur ameliorated the histological damage and decreased the germ cell apoptosis induced by Cd. Furthermore, after Cd exposure, B-cell lymphoma-2 expression was significantly decreased while Bax expression was increased. Pretreatment of rats with Cur protected against germ cell apoptosis by improving the expression of B-cell lymphoma-2 and reducing Bax. Additionally, Cd treatment increased reactive oxygen species, resulting in a decrease in antioxidant enzymes. However, pretreatment of rats with Cur followed by Cd administration led to a substantial decrease in reactive oxygen species levels and increased activities of antioxidant enzymes. Ultrastructural investigations revealed that damage to the mitochondrial structure was significantly ameliorated by Cur pretreatment in Cd-treated rats. Notably, Cur significantly activated the peroxisome proliferator-activated receptor gamma coactivator 1a/Sirtuins-3 signaling pathway. Overall, our data suggest that Cd induces germ cell apoptosis through mitochondrial-induced oxidative stress, but Cur pretreatment offers strong protection against Cd-induced reproductive toxicity.

Protective effects of Dioscin against sepsis-induced cardiomyopathy via regulation of toll-like receptor 4/MyD88/p65 signal pathway.

Dioscin has many pharmacological effects; however, its role in sepsis-induced cardiomyopathy (SIC) is unknown. Accordingly, we concentrate on elucidating the mechanism of Dioscin in SIC rat model. The SIC rat and H9c2 cell models were established by lipopolysaccharide (LPS) induction. The heart rate (HR), left ventricle ejection fraction (LVEF), mean arterial blood pressure (MAP), and heart weight index (HWI) of rats were evaluated. The myocardial tissue was observed by hematoxylin and eosin staining. 4-Hydroxy-2-nonenal (4-HNE) level in myocardial tissue was detected by immunohistochemistry. Superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) activities in serum samples of rats and H9c2 cells were determined by colorimetric assay. Bax, B-cell lymphoma-2 (Bcl-2), toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), phosphorylated-p65 (p-p65), and p65 levels in myocardial tissues of rats and treated H9c2 cells were measured by quantitative real-time PCR and Western blot. Viability and reactive oxygen species (ROS) accumulation of treated H9c2 cells were assayed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and dihydroethidium staining assays. Dioscin decreased HR and HWI, increased LVEF and MAP, alleviated the myocardial tissue damage, and reduced 4-HNE level in SIC rats. Dioscin reversed LPS-induced reduction on SOD, CAT, GSH, and Bcl-2 levels, and increment on Bax and TLR4 levels in rats and H9c2 cells. Overexpressed TLR4 attenuated the effects of Dioscin on promoting viability, as well as dwindling TLR4, ROS and MyD88 levels, and p-p65/p65 value in LPS-induced H9c2 cells. Protective effects of Dioscin against LPS-induced SIC are achieved via regulation of TLR4/MyD88/p65 signal pathway.

Small Molecule Functional Converter of B-Cell Lymphoma-2 (Bcl-2) Suppresses Breast Cancer Lung Metastasis.

The B-cell lymphoma-2 (Bcl-2) family of proteins plays a vital role in tumorigenesis. Cancer cells utilize the expression of Bcl-2 to evade therapy and develop resistance. Bcl-2 overexpression also causes cancer cells to be more invasive and metastatic. About 80% of cancer deaths are due to metastases, and yet targeted therapies for metastatic cancers are scarce. We discovered a small molecule, BFC1103, which changes the conformation of Bcl-2 to convert the antiapoptotic protein to a proapoptotic protein. BFC1103-induced apoptosis is dependent on the expression levels of Bcl-2, with higher levels causing more apoptosis. BFC1103 suppressed the growth of breast cancer lung metastasis. BFC1103 has the potential for further optimization and development for clinical testing in metastatic cancers that express Bcl-2. This study demonstrates a new approach to target Bcl-2 using a small molecule, BFC1103, to suppress metastatic disease.

Exploring the interplay between miRNAs, apoptosis and viral load, in Dengue virus infection

Dengue virus (DENV) is a major global health concern, causing millions of infections annually. Understanding the cellular response to DENV infection is crucial for developing effective therapies. This study provides an in-depth analysis of the cellular response to Dengue virus (DENV) infection, with a specific focus on the interplay between microRNAs (miRNAs), apoptosis, and viral load across different DENV serotypes. Utilizing a variety of cell lines infected with four DENV serotypes, the research methodically quantifies viral load, and the expression levels of miRNA-15, miRNA-16, and BCL2 protein, alongside measuring apoptosis markers. Methodologically, the study employs quantitative PCR for viral load and miRNA expression analysis, and Western blot for apoptosis and BCL2 detection, with a statistical framework that includes ANOVA and correlation analysis to discern significant differences and relationships. The findings reveal that despite similar viral loads across DENV serotypes, DENV-2 exhibits a marginally higher load. A notable upregulation of miRNA-15 and miRNA-16 correlates positively with increased viral load, suggesting their potential role in modulating viral replication. Concurrently, a marked activation of caspases 3 and 7, along with changes in BCL2 protein levels, underscores the role of apoptosis in the cellular response to DENV infection. Conclusively, the study enhances the understanding of miRNA involvement in DENV pathogenesis, highlighting miRNA-15 and miRNA-16 as potential regulatory agents in viral replication and apoptosis. These findings pave the way for further exploration into miRNA-based therapeutic strategies against DENV infection.

Effects of plumbagin on proliferation and apoptosis of human hepatocellular carcinoma cells based on CKB/p53 signaling pathway

To investigate the effects of plumbagin on the proliferation and apoptosis of human hepatoma Huh-7 cells and its mechanism based on the creatine kinase B(CKB)/p53 signaling pathway. Huh-7 cells were treated with plumbagin from 1 to 12 μmol·L~(-1) for cell counting kit-8(CCK-8) assay, and 1, 3, and 6 μmol·L~(-1) were determined as low, medium, and high concentrations of plumbagin for subsequent experiments. CKB gene was knocked out in Huh-7 cells by clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated proteins(Cas)-9 gene editing technology. CKB overexpression lentivirus was transfected into Huh-7 cells to up-regulate the expression of CKB. Cell proliferation and apoptosis were detected by plate cloning assay and flow cytometry. The mRNA expression of CKB was detected by quantitative real-time PCR(qRT-PCR). CKB, p53, mouse double minute 2 homolog(MDM2), B-cell lymphoma 2(Bcl-2), Bcl-2 associated X protein(Bax), and caspase-3 protein were detected by Western blot(WB). The results showed that plumbagin significantly inhibited the proliferation of Huh-7 cells and induced cell apoptosis. Compared with the control group, the apoptosis level was significantly increased in the plumbagin group, while the apoptosis level was significantly decreased in the plumbagin combined with the apoptosis inhibitor group. Plumbagin significantly down-regulated the protein expression levels of CKB, Bcl-2, and MDM2 and up-regulated the protein expression levels of p53, Bax, and caspase-3. Knockdown of the CKB gene decreased the proliferative ability of Huh-7 cells, increased the apoptotic rate, decreased the expression levels of Bcl-2 and MDM2 proteins, and increased the expression levels of p53, Bax, and caspase-3 proteins. After up-regulation of CKB expression, the proliferation ability of Huh-7 cells was enhanced, and the protein expression levels of Bcl-2 and MDM2 were elevated. The protein expression levels of p53, Bax, and caspase-3 were decreased. In addition, plumbagin reversed the effect of overexpression of CKB on the proliferation and apoptosis of Huh-7 cells. In conclusion, plumbagin significantly inhibited the proliferative ability of Huh-7 cells, and the mechanism may be related to the inhibition of CKB expression, activation of the p53 signaling pathway, and regulation of the expression of mitochondrial-associated apoptotic proteins, ultimately inducing cell apoptosis.

Glycyrrhizic acid inhibits DNA damage repair and enhances cisplatin-induced apoptosis of melanoma cells.

This research was designed to prospect the mechanism and impact of glycyrrhizic acid (GA) on DNA damage repair and cisplatin (CP)-induced apoptosis of melanoma cells. First, human melanoma cell SK-MEL-28 was stimulated using GA for 24, 48, and 72 h. Then, the optimal treatment time and dosage were selected. After that, cell counting kit-8 (CCK-8) was employed for testing the cell viability, flow cytometry for the apoptosis, comet assay for the DNA damage of cells, and western blot for the cleaved-Caspase3, Caspase3, Bcl-2, and γH2AX protein expression levels. The experimental outcomes exhibited that as the GA concentration climbed up, the SK-MEL-28 cell viability dropped largely, while the apoptosis level raised significantly, especially at the concentration of 100 μm. In addition, compared with GA or CPtreatment only, CP combined with GA notably suppressed the viability of melanoma cells and promoted cell apoptosis at the cytological level. At the protein level, the combined treatment notably downregulated the Bcl-2 and Caspase3 expression levels, while significantly upregulated the cleaved-Caspase3 and γH2AX expression levels. Besides, CP + GA treatment promoted DNA damage at the DNA molecular level. Collectively, both GA and CP can inhibit DNA damage repair and enhance the apoptosis of SK-MEL-28 cells, and the synergistic treatment of both exhibits better efficacy.

Clusterin can mediate apoptosis-induced molecular mechanisms in immune thrombocytopenia

AbstractAbnormalities in the apoptosis pathway have been implicated into the pathogenesis of various autoimmune diseases, including immune thrombocytopenia (ITP). Our data suggest that mechanisms associated with impaired clusterin-mediated apoptosis might play a role in the pathophysiology of ITP platelets and their production by MKs. Platelet-rich plasma from 10 patients with ITP compared with healthy controls was used for the apoptosis proteomic profiling and clusterin (CLU) expression validation by reverse transcription polymerase chain reaction. We used the megakaryoblastic (MEG-01) cell line, treated for 2 hours with plasma from patients with newly diagnosed ND), chronic ITP or healthy controls and pan-caspase inhibitor (Z-VAD-FMK), apoptosis inducer ABT-737, rotenone (Rot), or rapamycin (Rap). Our apoptosis proteomic profiling revealed significantly increased expression levels of certain apoptotic genes such as CLU, phospho-p53 (S46), procaspase-3, and cleaved caspase 3 (CASP-3) in patients with ITP compared with healthy controls. Treatment with pan-caspase inhibitor or Rap had a significant downregulatory effect at messenger RNA (mRNA) level for CLU; CASP-3, -8, and -9; p53; and B-cell lymphoma-2–associated X protein (BAX) in ITP plasma–treated cells in comparison with control plasma–treated MEG-01 cells, whereas Rot or ABT-737 had opposite effects. We observed a significant downregulation of mRNA expression levels of these apoptotic markers in ITP plasma–treated and CLU or glucose-regulated protein 78 small interfering RNA–transfected MEG-01 cells. Our results indicate an upregulation of CLU and BAX in platelets and MKs which may contribute to deciphering the cause of platelet destruction in ITP disease.

Mechanism of miR-221-3p inhibiting cadmium-induced apoptosis of TM3 cells through DDIT4

To investigate the mechanism of DNA-damage-inducible transcript 4(DDIT4)targeting miR-221-3p in microRNA(miRNA) on cadmium-induced apoptosis of mouse testicular stromal cells. The activity of mouse testicular interstitial cells(TM3) was detected by CCK-8 after exposure to different concentrations of cadmium(0, 10, 20, 30, 40 μmol/L). Total RNA was extracted from cadmium-treated TM3 cells, and the significantly differentially expressed miRNA was screened with fold change(FC)&gt;1.2 and P&lt;0.05 as the criterion. TM3 cells were divided into blank control group, negative control group, cadmium exposure group(CdCl_2, 20 μmol/L), and cadmium+miR-221-3p mimic group. miR-221-3p mimic group was transfected into TM3 cells first, combined with cadmium exposure for 24 hours. The cell morphology was detected by Hoechst staining, and the apoptosis rate was analyzed by flow cytometry. Quantitative real-time PCR(qRT-PCR) and Western blot were used to detect DDIT4 expression. Dual luciferase reporter gene assay verified the binding of miR-221-3p to DDIT4. The function of DDIT4 and its relationship with apoptosis were analyzed by bioinformatics. The expression levels of B-cell lymphoma-2(Bcl-2) and Bcl-2 associated X protein(BAX) were observed after overexpression of miR-221-3p. Cadmium treatment of TM3 cells could reduce cell activity and there was a dose-effect relationship. The cell morphology showed that compared with the control group, the cells were wrinkled and the nuclei were heavily stained, and the apoptosis rate increased to 19.66%±0.45%(P&lt;0.01). Compared with the cadmium exposure group, the normal morphologic cells increased in the cadmium exposure +miR-221-3p mimic group, and the apoptosis rate decreased to 13.76%±0.37%(P&lt;0.05). The expression level of miR-221-3p was down-regulated(P&lt;0.01), and the expression level of DDIT4 was up-regulated(P&lt;0.05). Bioinformatics analysis and dual luciferase report analysis showed that DDIT4 was one of the target genes of miR-221-3p. Compared with the cadmium exposure group, the expression level of DDIT4 in the cadmium+miR-221-3p mimic group was down-regulated(P&lt;0.05), and the ratio of Bcl-2/BAX was increased from 0.54±0.03 to 0.71±0.04. miR-221-3p inhibits cadmium-induced apoptosis of TM3 cells by targeting DDIT4.

Clinical pharmacokinetics and pharmacodynamics of venetoclax, a selective B-cell lymphoma-2 inhibitor.

Venetoclax, a highly potent BCL-2 inhibitor, is indicated for treatment of some hematologic malignancies as monotherapy, and/or in combination with other agents. Venetoclax pharmacokinetics has been extensively characterized in patients and healthy participants. After oral dosing, the median time to reach maximum plasma concentration ranged from 5 to 8 h and harmonic mean half-life ranged from 14 to 18 h. Food increases venetoclax bioavailability by 3-5-fold and venetoclax should be administered with food to ensure adequate and consistent bioavailability. Venetoclax is eliminated via cytochrome P450 (CYP)3A metabolism, and a negligible amount of unchanged drug is excreted in urine. Strong CYP3A/P-glycoprotein inhibitors increased venetoclax exposures (AUC) by 1.44- to 6.90-fold while a significant decrease (71%) has been observed when dosed with strong CYP3 inducers. Venetoclax does not inhibit or induce CYP enzymes or transporters. Venetoclax pharmacokinetics is not appreciably altered by age, weight, sex, but the exposure is up to twofold higher in participants from Asian countries. Mild-to-severe renal impairment or end-stage renal disease do not alter venetoclax exposures, and venetoclax is not cleared by dialysis. Although mild-to-moderate hepatic impairment does not affect venetoclax exposures, twofold higher exposure was observed in subjects with severe hepatic impairment. Venetoclax exposure is comparable across patients with different hematologic malignancies and healthy participants. Overall, venetoclax exposure is only affected by food and CYP3A modulators and is only higher in Asian subjects and subjects with severe hepatic impairment. Venetoclax exposure-response relationships are malignancy-dependent and can be different between monotherapy and combination therapy.

Modeling the Effects of Cell Stress and Ca2+ Dysregulation on the Crosstalk Between Apoptosis and Autophagy in Neurodegenerative Diseases

BACKGROUND: Apoptosis is a highly regulated and irreversible process of cell death, while autophagy maintains cellular homeostasis by degrading and recycling cytoplasmic components, such as aggregated and damaged proteins (Elmore, 2007; Glick et al., 2010). Dysregulation of both processes is observed in neurodegenerative diseases (NDs) (Ghavami et al., 2014). For example, in Alzheimer’s disease (AD), accumulation of amyloid-β peptides is attributed to dysregulated autophagy (Han et al., 2020). Dysregulated autophagy can further induce apoptosis and neurodegeneration (Chung et al., 2018). Although studies have focused on signaling pathways involved in apoptosis and autophagy extensively in other cell types, an effective framework to clarify their interplay in the nervous system is lacking. Here we develop a simplified network model of the key pathways involved in apoptosis and autophagy to study their interplay and dysregulation in NDs. Specifically, we model triggers such as cell stress and Ca2+ dysregulation implicated in aging and NDs and simulate their effects on cell fate. Although much of the empirical support to model development came from studies in other cell types, our integrative framework of the ubiquitous and non-cell autonomous pathways can offer deeper insights into the pathophysiology in NDs. METHODS: Ordinary differential equations (ODEs) were used to model the network of molecular compartments, and the rates of change in their abundances and interactions. The interconnections between these compartments, for example, the inhibitory role of caspases on autophagy-inducing Beclin-1(BECN1), are validated in empirical work and adopted in previous modeling studies (Bogdał et al., 2013; Fan and Zong, 2013; Mariño et al., 2014; Tavassoly et al., 2015; Wirawan et al., 2010; Yin et al., 2017). MATLAB was used to code and simulate the model; ode45 was the numerical integration method of choice. RESULTS: We developed an integrative framework for the signaling pathways of apoptosis and autophagy. Our model adapted and merged three previously reported dynamic network models (Bogdal et al., 2013; Tavassoly et al., 2015; Yin et al., 2017) which also included pathways relevant to NDs. A hypothetical cell stress input and cytosolic Ca2+ concentration in our network model represent extrinsic and intrinsic triggers respectively. Using such a computational approach, we are investigating the multiplexing role of Beclin 1 protein (part of Bcl-2 protein family), mTOR (mammalian target of rapamycin) kinase and JNK (Jun N-terminal kinase) in the synergy between autophagy and apoptosis. Simulation experiments are underway to predict the mechanisms of cell vulnerability versus resilience implicated in NDs involving these pathways. CONCLUSION: Our network provides a framework based on which experiments can be designed to validate model predictions and better understand the dynamic processes involved in NDs. Although NDs are complex and chronic, understanding the effects of common triggers such as cell stress and disrupted Ca2+ homeostasis on cell fate determination is critical to slow ND progression. Therefore, our study delineating the dynamic crosstalk between apoptosis and autophagy offers crucial insights into ND pathophysiology and suggests specific protein targets within these key common pathways. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Virtual Screening of Small Molecules Targeting BCL2 with Machine Learning, Molecular Docking, and MD Simulation.

This study aimed to identify potential BCL-2 small molecule inhibitors using deep neural networks (DNN) and random forest (RF), algorithms as well as molecular docking and molecular dynamics (MD) simulations to screen a library of small molecules. The RF model classified 61% (2355/3867) of molecules as 'Active'. Further analysis through molecular docking with Vina identified CHEMBL3940231, CHEMBL3938023, and CHEMBL3947358 as top-scored small molecules with docking scores of -11, -10.9, and 10.8 kcal/mol, respectively. MD simulations validated these compounds' stability and binding affinity to the BCL2 protein.