Activation Of Apoptotic Signaling Pathway Research Articles

Thallium-induced DNA damage, genetic, and epigenetic alterations.

Thallium (Tl) is a toxic heavy metal responsible for noxious effects in living organisms. As a pollutant, Tl can be found in the environment at high concentrations, especially in industrial areas. Systemic toxicity induced by this toxic metal can affect cell metabolism, including redox alterations, mitochondrial dysfunction, and activation of apoptotic signaling pathways. Recent focus on Tl toxicity has been devoted to the characterization of its effects at the nuclear level, with emphasis on DNA, which, in turn, may be responsible for cytogenetic damage, mutations, and epigenetic changes. In this work, we review and discuss past and recent evidence on the toxic effects of Tl at the systemic level and its effects on DNA. We also address Tl's role in cancer and its control.

A Review of the Global Microgreens’ Market by most Popular Species Grown, Farming types and Practices, end users, Revenue Generated: Opportunity Analysis, and Industry Forecast

Background: Alcoholic liver damage is caused by long-term and heavy alcohol consumption, which leads to many diseases and even cancer. α-Pinene has been shown to have antioxidant and anti-inflammatory activity, however, it is still unclear the relationship between α-Pinene and alcohol-induced liver injury. The potential molecular mechanisms of α-pinene in reducing alcohol-induced liver injury in mice were investigated in this study. Materials and methods: The C57BL/6 mice were randomly divided into five groups, which were the control groups (physiological saline, 0.2mL per days), alcohol group (50% alcohol, 5 mL/kg bw/day), alcohol with low/medium/high dosage α-pinene treatment group ((7.2 mg/kg bw, 14.4 mg/kg bw, 28.8 mg/kg bw, dissolved in 50% alcohol, Separately). The dosing method for mice is via oral gavage. After 8 weeks of experimentation, mouse serum and liver were collected for further testing. Result: The increased antioxidant enzyme activities demonstrated the alleviated effect of α-pinene against alcohol-induced mouse liver injury. Moreover, in liver tissues, α-pinene promoted nucleus translocation of nuclear factor-erythroid-2-related factor 2 (NRF2) and transcription of antioxidant target genes, including heme oxygenase 1 (HMOX-1 / HO-1), NAD[P]H quinone dehydrogenase 1 (NQO-1), and glutathione S-transferase alpha 1 (Gsta-1). Meanwhile, α-pinene promoted the protein expression of autophagy-related proteins and inhibited the increase of inflammatory factors caused by chronic alcohol intake. Furthermore, α-pinene partially inhibited the activation of apoptotic signaling pathways by increasing the expression of Bcl-2 and decreasing Bax and cleaved caspase-3 proteins. Conclusion: Taken together, our results indicated that α-pinene might alleviate alcoholic liver injury by reducing lipid accumulation, enhancing anti-oxidative stress and anti-inflammatory, activating autophagy, and inhibiting cell apoptosis.

The Alleviated Effect of α-Pinene on Amidst Alcoholic Liver Injury Pathology Through Autophagy Activation in Mice

Background: Alcoholic liver damage is caused by long-term and heavy alcohol consumption, which leads to many diseases and even cancer. α-Pinene has been shown to have antioxidant and anti-inflammatory activity, however, it is still unclear the relationship between α-Pinene and alcohol-induced liver injury. The potential molecular mechanisms of α-pinene in reducing alcohol-induced liver injury in mice were investigated in this study. Materials and methods: The C57BL/6 mice were randomly divided into five groups, which were the control groups (physiological saline, 0.2mL per days), alcohol group (50% alcohol, 5 mL/kg bw/day), alcohol with low/medium/high dosage α-pinene treatment group ((7.2 mg/kg bw, 14.4 mg/kg bw, 28.8 mg/kg bw, dissolved in 50% alcohol, Separately). The dosing method for mice is via oral gavage. After 8 weeks of experimentation, mouse serum and liver were collected for further testing. Result: The increased antioxidant enzyme activities demonstrated the alleviated effect of α-pinene against alcohol-induced mouse liver injury. Moreover, in liver tissues, α-pinene promoted nucleus translocation of nuclear factor-erythroid-2-related factor 2 (NRF2) and transcription of antioxidant target genes, including heme oxygenase 1 (HMOX-1 / HO-1), NAD[P]H quinone dehydrogenase 1 (NQO-1), and glutathione S-transferase alpha 1 (Gsta-1). Meanwhile, α-pinene promoted the protein expression of autophagy-related proteins and inhibited the increase of inflammatory factors caused by chronic alcohol intake. Furthermore, α-pinene partially inhibited the activation of apoptotic signaling pathways by increasing the expression of Bcl-2 and decreasing Bax and cleaved caspase-3 proteins. Conclusion: Taken together, our results indicated that α-pinene might alleviate alcoholic liver injury by reducing lipid accumulation, enhancing anti-oxidative stress and anti-inflammatory, activating autophagy, and inhibiting cell apoptosis.

Two new Cd(II)/Zn(II) coordination polymers: luminescence properties and synergistic treatment activity with ultrasound therapy on uterine fibroids

ABSTRACT Through the self-assembly reaction of 5-substituted isophthalic acid and bis(imidazolyl) ligands with Cd(II) ion or Zn(II) ion, two new coordination polymers with the chemical formulae of [Cd(5-meo-ip)(bmip)]n (1) and [Zn(5-pro-ip)(bip)]n·2 n(H2O) (2) (5-meo-H2ip = 5-methoxyisophthalic acid, 5-pro-H2ip = 5-propoxyisophthalic acid, bmip = 1,3-bis(2-methylimidazolyl)propane bip = 1,3-bis(imidazolyl)propane) were successfully obtained and structurally characterized by a series of characterization techniques. Moreover, compounds 1–2 show intense blue luminescence at room temperature. Furthermore, the assessment of their treatment activity on the uterine fibroids combined with ultrasound therapy was evaluated and the specific mechanism was investigated at the same time. Firstly, the effect of compound treatment on uterine fibroids apoptosis was detected via flow cytometry. Next, the apoptotic signaling pathway activation was detected through the Caspase-3 and Caspase-8 Activity Assay Kit.

Cadmium-induced splenic lymphocytes anoikis is not mitigated by activating Nrf2-mediated antioxidative defense response

Cadmium (Cd) is a widely used heavy metal which is reported to exert extensive harm to the environment and human health. Owing to Cd being an element it is continuously enriched in the environment. The mechanism of splenic toxicity by Cd, however, is not yet clear. In order to explore the toxic mechanism of Cd exposure to the spleen, we added 0, 35, 70 and 140 mg/kg of Cd to the diet of chicken and fed them this diet for 90 days. Analysis of histopathological sections showed that Cd exposure damaged the spleen structure, the spleen red pulp, the white pulp boundary disappeared and the number of lymphocytes decreased significantly, suggesting that Cd exposure leads to organ injury to the spleen. Particularly, Cd-induced anoikis - a special form of programmed cell death caused by the loss of contact between cells and extracellular matrix and other cells - is associated with integrin-related cell detachment and activation of apoptotic signaling pathways. Moreover, Cd exposure leads to an increase in free radicals content and affects the activity of antioxidant enzymes resulting in oxidative stress. Simultaneously, Cd activated the body's antioxidant defense system mediated by the Nuclear factor related factor 2 (Nrf2) signaling pathway. Based on our results Cd-induced splenic lymphocytes anoikis is not mitigated by Nrf2-mediated antioxidative defense response.

Site-Specific Integration of TRAIL in iPSC-Derived Mesenchymal Stem Cells for Targeted Cancer Therapy.

Mesenchymal stem cells (MSCs) are a promising cellular vehicle for transferring anti-cancer factors to malignant tumors. Currently, a variety of anti-cancer agents, including the tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), have been loaded into MSCs derived from a range of sources through different engineering methods. These engineered MSCs exhibit enormous therapeutic potential for various cancers. To avoid the intrinsic defects of MSCs derived from tissues and the potential risk of viral vectors, TRAIL was site-specifically integrated into the ribosomal DNA (rDNA) locus of human-induced pluripotent stem cells (iPSCs) using a non-viral rDNA-targeting vector and transcription activator-like effector nickases (TALENickases). These genetically modified human iPSCs were differentiated into an unlimited number of homogeneous induced MSCs (TRAIL-iMSCs) that overexpressed TRAIL in both culture supernatants and cell lysates while maintaining MSC-like characteristics over continuous passages. We found that TRAIL-iMSCs significantly induced apoptosis in A375, A549, HepG2, and MCF-7 cells in vitro. After intravenous infusion, TRAIL-iMSCs had a prominent tissue tropism for A549 or MCF-7 xenografts and significantly inhibited tumor growth through the activation of apoptotic signaling pathways without obvious side effects in tumor-bearing mice models. Altogether, our results showed that TRAIL-iMSCs have strong anti-tumor effects in vitro and in vivo on a range of cancers. This study allows for the development of an unlimited number of therapeutic gene-targeted MSCs with stable quality and high homogeneity for cancer therapy, thus highlighting a universal and safe strategy for stem cell-based gene therapy with high potential for clinical applications.

Protective Effect of Fresh/Dry Dandelion Extracts on APAP-Overdose-Induced Acute Liver Injury.

To compare the liver protective activity of fresh/dried dandelion extracts against acetaminophen (APAP)-induced hepatotoxicity. Totally 90 Kunming mice were randomly divided into 10 groups according to body weight (9 mice for each group). The mice in the normal control and model (vehicle control) groups were administered sodium carboxymethyl cellulose (CMC-Na, 0.5%) only. Administration groups were pretreated with high and low-dose dry dandelion extract (1,000 or 500 g fresh herb dried and then decocted into 120 mL solution, DDE-H and DDE-L); low-, medium- and high-dose dandelion juice (250, 500, 1,000 g/120 mL, DJ-L, DJ-M, and DJ-H); fresh dandelions evaporation juice water (120 mL, DEJW); dry dandelion extract dissolved by pure water (1 kg/120 mL, DDED-PW); dry dandelion extract dissolved by DEJW (120 g/120 mL, DDED-DEJW) by oral gavage for 7 days at the dosage of 0.5 mL solution/10 g body weight; after that, except normal control group, all other groups were intraperitonealy injected with 350 mg/kg APAP to induce liver injury. Twenty hours after APAP administration, serum and liver tissue were collected and serum alanine aminotransferase (AST), aspartate transaminase (ALT), alkaline phosphatase (AKP), malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD) activities were quantified by biochemical kits; tumor necrosis factor (TNF-α), interleukin (IL)-2, and IL-1 β contents in liver tissue were determined by enzyme linked immunosorbent assay kits. Histopathological changes in liver tissues were observed by hematoxylin and eosin staining; TUNEL Assay and Hoechst 33258 staining were applied for cell apoptosis evaluation. The expressions of heme oxygenase-1 (HO-1), nuclear factor erythroid-2-related factor 2 (Nrf-2), caspase-9, B-cell leukemia/lymphoma 2 (Bcl-2), Bax and p-JNK were determined by Western blot analysis. Pretreatment with fresh dandelion juice (FDJ, including DJ-L, DJ-M, DJ-H, DEJW and DDED-DEJW) significantly decreased the levels of serum ALT, AST, AKP, TNF-α and IL-1β compared with vehicle control group (P<0.05 or P<0.01). Additionally, compared with the vehicle control group, FDJ decreased the levels of hepatic MDA and restored GSH levels and SOD activity in livers (P<0.05 or P<0.01). FDJ inhibited the overexpression of pro-inflammatory factors including cyclooxygenase-2 and inducible nitric oxide synthase in the liver tissues (P<0.05 or P<0.01). Furthermore, Western blot analysis revealed that FDJ pretreatment inhibited activation of apoptotic signaling pathways via decreasing of Bax, and caspase-9 and JNK protein expression, and inhibited activation of JNK pathway (P<0.05 or P<0.01). Liver histopathological observation provided further evidence that FDJ pretreatment significantly inhibited APAP-induced hepatocyte necrosis, inflammatory cell infiltration and congestion. FDJ pretreatment protects against APAP-induced hepatic injury by activating the Nrf-2/HO-1 pathway and inhibition of the intrinsic apoptosis pathway, and the effect of fresh dandelion extracts was superior to dried dandelion extracts in APAP hepatotoxicity model mice.

In-Vitro Application of Magnetic Hybrid Niosomes: Targeted siRNA-Delivery for Enhanced Breast Cancer Therapy.

Even though the administration of chemotherapeutic agents such as erlotinib is clinically established for the treatment of breast cancer, its efficiency and the therapy outcome can be greatly improved using RNA interference (RNAi) mechanisms for a combinational therapy. However, the cellular uptake of bare small interfering RNA (siRNA) is insufficient and its fast degradation in the bloodstream leads to a lacking delivery and no suitable accumulation of siRNA inside the target tissues. To address these problems, non-ionic surfactant vesicles (niosomes) were used as a nanocarrier platform to encapsulate Lifeguard (LFG)-specific siRNA inside the hydrophilic core. A preceding entrapment of superparamagnetic iron-oxide nanoparticles (FexOy-NPs) inside the niosomal bilayer structure was achieved in order to enhance the cellular uptake via an external magnetic manipulation. After verifying a highly effective entrapment of the siRNA, the resulting hybrid niosomes were administered to BT-474 cells in a combinational therapy with either erlotinib or trastuzumab and monitored regarding the induced apoptosis. The obtained results demonstrated that the nanocarrier successfully caused a downregulation of the LFG gene in BT-474 cells, which led to an increased efficacy of the chemotherapeutics compared to plainly added siRNA. Especially the application of an external magnetic field enhanced the internalization of siRNA, therefore increasing the activation of apoptotic signaling pathways. Considering the improved therapy outcome as well as the high encapsulation efficiency, the formulated hybrid niosomes meet the requirements for a cost-effective commercialization and can be considered as a promising candidate for future siRNA delivery agents.

Association Between Body Mass Index and Male Sperm Apoptosis and Apoptosis-Related Factors.

BackgroundAlthough obesity may affect reproductive functions, the molecular mechanisms of apoptosis-related biomarkers remain uncertain.ObjectiveTo examine the effects of body mass index on sperm quality and apoptosis-related factors in seminal plasma of men.MethodsData for 54 subfertile men were collected at our reproductive medical center. The men were divided into normal weight, overweight, and obese groups based on their body mass index (BMI). Sperm DNA fragmentation (sperm chromatin structure analysis), sperm apoptosis (annexin V), and sperm apoptosis-related factors (antibody array assay) were assessed and their relationships with BMI were analyzed.ResultsBMI was not significantly related to age, duration of infertility, duration of sexual abstinence, semen volume, sperm concentration, or rate of normal sperm morphology (p > 0.05). However, progressive sperm motility was significantly reduced and the rates of sperm DNA fragmentation index (DFI) and sperm apoptosis were significantly increased in overweight and obese men compared with men with normal BMI. Fas/Fasl, Bcl-2/Bax, caspase-3, caspase-8, p53, and p21 were all upregulated in the overweight and obese groups. Protein function annotation by Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that apoptosis-related factors were enriched in a network associated with activation of apoptotic signaling pathways, such as apoptosis and p53 signaling.ConclusionThese data suggest that increased BMI is associated with increased sperm apoptosis and sperm DNA damage, as well as accelerated expression of apoptosis-related factors via the activation of apoptotic signaling pathways.

Antitumor Effects of Ethanol Extract from Ventilago leiocarpa Benth on Sarcoma 180 Tumor-Bearing Mice and Possible Immune Mechanism.

To explore the antitumor effects of ethanol extract from Ventilago leiocarpa Benth (EEVLB) on sarcoma 180 (S180) tumor-bearing mice and the potential mechanism. Sixty mice were randomly assigned to 6 groups according to a random number table: normal group, model group, 5-fluorouracil (5-FU) group (0.02 g·kg-1), and high-, medium-, low-dose EEVLB groups (100, 84, and 56 g of raw material·kg-1 body weight, respectively), with 10 mice each group. All treatments were given once daily for 10 consecutive days. Effects of EEVLB on inhibiting tumor growth and immune function in mice were evaluated among all groups after the treatments by detecting tumor inhibition rate, organ index, serum levels of interleukin (IL)-2, -6, -10, CD3+CD4+ T lymphocytes, CD4+/CD8+ ratio, caspase-3 and Bcl-2. EEVLB with different concentrations achieved inhibition of tumor growth in vivo, wherein the high-dose group showed the most significant reduction in tumor weight and increased apoptosis of tumor cells (P<0.05). In addition, both net weight gain and spleen index of mice showed uptrend in EEVLB treatment groups (P<0.05). Besides, serum levels of IL-2 and IL-6, percentages of CD3+CD4+ T lymphocytes and ratio of CD4+/CD8+ in peripheral blood were elevated in high- and medium-dose EEVLB groups compared with the model group (P<0.05). Also, upregulation of caspase-3 and downregulation of Bcl-2 were observed at protein levels in the high-dose EEVLB group (P<0.01). EEVLB exhibits promising antitumor activity in vivo. This effect might be due to activation of apoptotic signaling pathway, increase of cytokine levels and enhancement of immune function in tumor-bearing mice.

Protective Effects of Glucose-Related Protein 78 and 94 on Cisplatin-Mediated Ototoxicity.

Cisplatin is a widely used chemotherapeutic drug for treating various solid tumors. Ototoxicity is a major dose-limiting side effect of cisplatin, which causes progressive and irreversible sensorineural hearing loss. Here, we examined the protective effects of glucose-related protein (GRP) 78 and 94, also identified as endoplasmic reticulum (ER) chaperone proteins, on cisplatin-induced ototoxicity. Treating murine auditory cells (HEI-OC1) with 25 μM cisplatin for 24 h increased cell death resulting from excessive intracellular reactive oxygen species (ROS) accumulation and caspase-involved apoptotic signaling pathway activation with subsequent DNA fragmentation. GRP78 and GRP94 expression was increased in cells treated with 3 nM thapsigargin or 0.1 μg/mL tunicamycin for 24 h, referred to as mild ER stress condition. This condition, prior to cisplatin exposure, attenuated cisplatin-induced ototoxicity. The involvement of GRP78 and GRP94 induction was demonstrated by the knockdown of GRP78 or GRP94 expression using small interfering RNAs, which abolished the protective effect of mild ER stress condition on cisplatin-induced cytotoxicity. These results indicated that GRP78 and GRP94 induction plays a protective role in remediating cisplatin-ototoxicity.

31P and 13C solid-state NMR analysis of morphological changes of phospholipid bilayers containing glucagon during fibril formation of glucagon under neutral condition

Glucagon is a 29 amino acid peptide hormone secreted by pancreatic α-cells that interacts with specific receptors located in various organs. Glucagon tends to form gel-like fibrillar aggregates that are cytotoxic due to their activation of apoptotic signaling pathways. To understand the glucagon-membrane interactions, morphological changes in dimyristoylphosphatidylcholine (DMPC) bilayers containing glucagon in neutral solution were investigated by observing 31P NMR spectra. First, lipid bilayers with a DMPC/glucagon molar ratio of 50/1 were observed. One day after preparing the DMPC/glucagon lipid bilayer sample, lipid bilayers were disrupted below the phase transition temperature (Tc). Membrane disruption was reduced 2 days after preparation due to the reduction of glucagon-DMPC interaction, and subsequently increased by 4 days and was reduced again by 7 days. TEM measurements showed that small ellipsoidal intermediates of glucagon were observed inside the small size of lipid bilayer after 4 days, while fibrils grew inside lipid bilayer after 19 days. These results indicate that morphological changes in DMPC/glucagon lipid bilayers are correlated with the evolution of glucagon aggregate state. Particularly, fibril intermediate shows a strong glucagon lipid bilayer interaction. We further investigated the structure and kinetics of glucagon fibril formation inside the DMPC lipid bilayer in a neutral solution using 13C solid-state NMR spectroscopy. α-Helical structures were observed around Gly4 and Ala19 in the monomeric form, which changed to β-sheet structures in the fibril form. The fibrillation process can be explained by a two-step autocatalytic reaction mechanism in which the first step is a homogeneous nuclear formation (k1), and the second step is an autocatalytic heterogeneous fibrillation process (k2).

Glycyrol exerts potent therapeutic effect on lung cancer via directly inactivating T-LAK cell-originated protein kinase

Molecular targeted therapy for non-small cell lung cancer (NSCLC) has demonstrated promising outcomes. T-lymphokine-activated killer cell-originated protein kinase (TOPK) is found overexpressed in many cancer types such as NSCLC, and is considered to be an effective target for lung cancer treatment. In the present study, we found that glycyrol (GC), a representative coumarin compound isolated from licorice, was highly effective against several human NSCLC cell lines in vitro, and significantly suppressed tumor growth in vivo. Mechanistically, we demonstrated that GC can strongly bind to the TOPK protein and inhibited its kinase activity, leading to the activation of apoptotic signaling pathways. The findings of the present study suggest that GC is a novel promising TOPK inhibitor and this compound deserves to be further investigated for its potential anti-NSCLC activity.

Astrocyte Viability and Functionality in Spatially Confined Microcavitation Zone.

Blast-induced traumatic brain injury (bTBI) can result in cell/tissue damage and lead to clinical and neuropsychiatric symptoms. Shock waves from a blast propagate through the brain and initiate cascades of mechanical and physiological events that can adversely affect the brain function. Although studies using animal models and brain slices have shown macroscale changes in the brain tissue in response to blast, systematic elucidation of coupling mechanisms is currently lacking. One mechanism that has been postulated and demonstrated repeatedly is the blast-induced generation and subsequent collapse of micron-size bubbles (i.e., microcavitation). Using a custom-designed exposure system, we have previously reported that upon collapsing of microbubbles, astrocytes exhibited changes in the cell viability, cellular biomechanics, production of reactive oxygen species, and activation of apoptotic signaling pathways. In this paper, we have applied microfabrication techniques and seeded astrocytes in a spatially controlled manner to determine the extent of cell damage from the site of the collapse of microbubbles. Such a novel experimental design is proven to facilitate our effort to examine the altered cell viability and functionality by monitoring the transient calcium spiking activity in real-time. We now report that the effect of microcavitation depends on the distance from which cells are seeded, and the cell functionality assessed by calcium dynamics is significantly diminished in the cells located within ∼800 μm of the collapsing microbubbles. Both calcium influx across the cell membrane via N-type calcium channels and intracellular calcium store are altered in response to microcavitation. Finally, the FDA-approved poloxamer 188 (P188) was used to reconstitute the compromised cell membrane and restore the cell's reparative capability. This finding may lead to a feasible treatment for partially mitigating the tissue damage associated with bTBI.

Indole-3-Carbinol Induces Apoptosis in Human Osteosarcoma MG-63 and U2OS Cells.

This study was focused on investigating the anticancer potential of indole-3-carbinol (I3C) against osteosarcoma MG-63 and U2OS cells. A wound healing assay indicated that IC3 inhibited migration of MG-63 and U2OS cells. MTT, WST-1, and colony formation assays revealed that treatment of MG-63 and U2OS cells with I3C decreased cell viability. Fluorescence-activated cell sorting (FACS) analysis showed that I3C induced apoptosis in a dose- and time-dependent manner in MG-63 and U2OS cells. Moreover, via terminal deoxynucleotidyl transferase- (TdT-) mediated dUTP-biotin nick-end labeling (TUNEL) assay, we detected that I3C induced DNA fragmentation. Western blotting demonstrated that activated forms of caspase-3, caspase-7, and caspase-9, as well as poly (ADP-ribose) polymerase (PARP) were increased in MG-63 and U2OS cells, following treatment with I3C. Furthermore, protein expression levels of FOXO3, Bax, and Bim extra-large form were increased while those of Akt, JNK, p38, phosphorylated ERK, and Bcl-xL were decreased by I3C treatment in MG-63 and U2OS cells. Thus, the study indicates that I3C may induce apoptosis in human osteosarcoma MG-63 and U2OS cells via the activation of apoptotic signaling pathways by FOXO3.

STAT3 inhibition induces Bax-dependent apoptosis in liver tumor myeloid-derived suppressor cells.

Immunosuppressive myeloid-derived suppressor cells (MDSC) subvert antitumor immunity and limit the efficacy of chimeric antigen receptor T cells (CAR-T). Previously, we reported that the GM-CSF/JAK2/STAT3 axis drives liver-associated MDSC (L-MDSC) proliferation and blockade of this axis rescued antitumor immunity. We extended these findings in our murine liver metastasis (LM) model, by treating tumor-bearing mice with STAT3 inhibitors (STATTIC or BBI608) to further our understanding of how STAT3 drives L-MDSC suppressive function. STAT3 inhibition caused significant reduction of tumor burden as well as L-MDSC frequencies due to decrease in pSTAT3 levels. L-MDSC isolated from STATTIC or BBI608-treated mice had significantly reduced suppressive function. STAT3 inhibition of L-MDSC was associated with enhanced antitumor activity of CAR-T. Further investigation demonstrated activation of apoptotic signaling pathways in L-MDSC following STAT3 inhibition as evidenced by an upregulation of the pro-apoptotic proteins Bax, cleaved caspase-3, and downregulation of the anti-apoptotic protein Bcl-2. Accordingly, there was also a decrease of pro-survival markers, pErk and pAkt, and an increase in pro-death marker, Fas, with activation of downstream JNK and p38 MAPK. These findings represent a previously unrecognized link between STAT3 inhibition and Fas-induced apoptosis of MDSCs. Our findings suggest that inhibiting STAT3 has potential clinical application for enhancing the efficacy of CAR-T cells in LM through modulation of L-MDSC.

Dietary α-Mangostin Provides Protective Effects against Acetaminophen-Induced Hepatotoxicity in Mice via Akt/mTOR-Mediated Inhibition of Autophagy and Apoptosis.

Acetaminophen overdose-induced hepatotoxicity is the most common cause of acute liver failure in many countries. Previously, alpha-mangostin (α-MG) has been confirmed to exert protective effects on a variety of liver injuries, but the protective effect on acetaminophen-induced acute liver injury (ALI) remains largely unknown. This work investigated the regulatory effect and underlying cellular mechanisms of α-MG action to attenuate acetaminophen-induced hepatotoxicity in mice. The increased serum aminotransferase levels and glutathione (GSH) content and reduced malondialdehyde (MDA) demonstrated the protective effect of α-MG against acetaminophen-induced hepatotoxicity. In addition, α-MG pretreatment inhibited increases in tumor necrosis factor (TNF-α) and interleukin-1β (IL-1β) caused by exposure of mice to acetaminophen. In liver tissues, α-MG inhibited the protein expression of autophagy-related microtubule-associated protein light chain 3 (LC3) and BCL2/adenovirus E1B protein-interacting protein 3 (BNIP3). Western blotting analysis of liver tissues also proved evidence that α-MG partially inhibited the activation of apoptotic signaling pathways via increasing the expression of Bcl-2 and decreasing Bax and cleaved caspase 3 proteins. In addition, α-MG could in part downregulate the increase in p62 level and upregulate the decrease in p-mTOR, p-AKT and LC3 II /LC3 I ratio in autophagy signaling pathways in the mouse liver. Taken together, our findings proved novel perspectives that detoxification effect of α-MG on acetaminophen-induced ALI might be due to the alterations in Akt/mTOR pathway in the liver.

Saponins (Ginsenosides) from the Leaves of Panax quinquefolius Ameliorated Acetaminophen-Induced Hepatotoxicity in Mice.

Acetaminophen (APAP) overdose is one of the most common inducements of drug-induced liver injury (DILI) in the world. The main purpose of this paper was to investigate the liver protection activity of saponins (ginsenosides) from the leaves of Panax quinquefolius (PQS) against APAP-induced hepatotoxicity, and the involved mechanisms were demonstrated for the first time. Mice were pretreated with PQS (150 and 300 mg/kg) by oral gavage for 7 days before being treated with 250 mg/kg APAP. Severe liver injury was exerted at 24 h post-APAP, and hepatotoxicity was assessed. Our results showed that pretreatment with PQS significantly decreased the serum alanine aminotransferase (ALT), aspartate transaminase (AST), tumor necrosis factor (TNF-α), and interleukin-1β (IL-1β) levels in a dose-dependent manner as compared to the APAP administration. Meanwhile, compared with that in the APAP group, PQS decreased hepatic malondialdehyde (MDA) contents and 4-hydroxynonenal (4-HNE) expression and restored reduced glutathione (GSH) content and superoxide dismutase (SOD) activity in livers of mice. PQS inhibited the overexpression of pro-inflammatory factors cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in the liver tissues. Furthermore, Western blotting analysis revealed that PQS pretreatment inhibited the activation of apoptotic signaling pathways via increase of Bcl-2 and decrease of Bax and caspase-3 protein expression levels. Liver histopathological observation provided further evidence that PQS pretreatment significantly inhibited APAP-induced hepatocyte necrosis, inflammatory cell infiltration, and congestion. Biological indicators of nitrative stress such as 3-nitrotyrosine (3-NT) were inhibited after PQS pretreatment, compared to the APAP group. The present study clearly demonstrates that PQS exerts a protective effect against APAP-induced hepatic injury because of its antioxidant, anti-apoptotic, and anti-inflammatory activities. The findings from the present investigation show that PQS might be a promising candidate treatment agent against drug-induced ALI.

Neurotoxicity of alkylated polycyclic aromatic compounds in human neuroblastoma cells

ABSTRACTPolycyclic aromatic compounds (PAC) are ubiquitous environmental pollutants originating from incomplete combustion processes. While the toxicity of parent PAC such as benzo[a]pyrene (BaP) is well characterized, effects of other alkyl-PAC dibenzothiophene (DBT) and retene (Ret) are not well established. The aim of this study was to examine the underlying relative neurotoxic mechanisms attributed to BaP (parent PAH), DBT and Ret (alkyl-PACs) using human neuroblastoma SK-N-SH cells. The lethal concentrations (LC10 and LC20) were found at approximately 10 µM and 40 µM, respectively after 24-h exposure of SK-N-SH cells. It was hypothesized that PAC trigger reactive oxygen species (ROS) production, leading to activation of apoptotic signaling pathways. Differentiated neuronal cells were treated with three compounds at (0.5–40 µM) for 24 h. There was a significant concentration-dependent increase in levels of ROS, even at sub-lethal levels of 1 µM Ret. The mitochondrial membrane potential (MMP) was significantly decreased. Real-time RT-PCR results showed up-regulation of pro-apoptotic genes and down-regulation of antioxidative genes expression in BaP-, DBT-, and Ret-treated SK-N-SH cells. Cytochrome c protein levels and lipid peroxidation (LPO) were also significantly elevated in a concentration-related manner. Data demonstrated that BaP-, DBT-, or Ret-induced neuronal cell damage involved oxidative stress generation through mitochondria-mediated apoptosis pathway. Alkyl-PAC also exhibited higher potency in ROS induction and reduction of MMP than parent PAC. These findings may be important for environmental risk assessment attributed to exposure to PAC.

Glaucarubinone sensitizes KB cells to paclitaxel by inhibiting ABC transporters via ROS-dependent and p53-mediated activation of apoptotic signaling pathways.

Multidrug resistance (MDR) is considered to be the major contributor to failure of chemotherapy in oral squamous cell carcinoma (SCC). This study was aimed to explore the effects and mechanisms of glaucarubinone (GLU), one of the major quassinoids from Simarouba glauca DC, in potentiating cytotoxicity of paclitaxel (PTX), an anticancer drug in KB cells. Our data showed that the administration of GLU pre-treatment significantly enhanced PTX anti-proliferative effect in ABCB1 over-expressing KB cells. The Rh 123 drug efflux studies revealed that there was a significant transport function inhibition by GLU-PTX treatment. Interestingly, it was also found that this enhanced anticancer efficacy of GLU was associated with PTX-induced cell arrest in the G2/M phase of cell cycle. Further, the combined treatment of GLU-PTX had significant decrease in the expression levels of P-gp, MRPs, and BCRP in resistant KB cells at both mRNA and protein levels. Furthermore, the combination treatments showed significant reactive oxygen species (ROS) production, chromatin condensation and reduced mitochondrial membrane potential in resistant KB cells. The results from DNA fragmentation analysis also demonstrated the GLU induced apoptosis in KB cells and its synergy with PTX. Importantly, GLU and/or PTX triggered apoptosis through the activation of pro-apoptotic proteins such as p53, Bax, and caspase-9. Our findings demonstrated for the first time that GLU causes cell death in human oral cancer cells via the ROS-dependent suppression of MDR transporters and p53-mediated activation of the intrinsic mitochondrial pathway of apoptosis. Additionally, the present study also focussed on investigation of the protective effect of GLU and combination drugs in human normal blood lymphocytes. Normal blood lymphocytes assay indicated that GLU is able to induce selective toxicity in cancer cells and in silico molecular docking studies support the choice of GLU as ABC inhibitor to enhance PTX efficacy. Thus, GLU has the potential to enhance the activity of PTX and hence can be a good alternate treatment strategy for the reversal of PTX resistance.