Apoptotic Regulatory Proteins Research Articles

An 8-aminoquinoline-naphthyl copper complex causes apoptotic cell death by modulating the expression of apoptotic regulatory proteins in breast cancer cells

Breast cancer is one of the most common cancers globally and a leading cause of cancer-related deaths among women. Despite the combination of chemotherapy with targeted therapy, including monoclonal antibodies and kinase inhibitors, drug resistance and treatment failure remain a common occurrence. Copper, complexed to various organic ligands, has gained attention as potential chemotherapeutic agents due to its perceived decreased toxicity to normal cells. The cytotoxic efficacy and the mechanism of cell death of an 8-aminoquinoline-naphthyl copper complex (Cu8AqN) in MCF-7 and MDA-MB-231 breast cancer cell lines was investigated. The complex inhibited the growth of MCF-7 and MDA-MB-231 cells with IC50 values of 2.54 ± 0.69 μM and 3.31 ± 0.06 μM, respectively. Nuclear fragmentation, annexin V binding, and increased caspase-3/7 activity indicated apoptotic cell death. The loss of mitochondrial membrane potential, an increase in caspase-9 activity, the absence of active caspase-8 and a decrease of tumour necrosis factor receptor 1(TNFR1) expression supported activation of the intrinsic apoptotic pathway. Increased ROS formation and increased expression of haem oxygenase-1 (HMOX-1) indicated activation of cellular stress pathways. Expression of p21 protein in the nuclei was increased indicating cell cycle arrest, whilst the expression of inhibitor of apoptosis proteins (IAPs); cIAP1, XIAP and survivin were decreased, creating a pro-apoptotic environment. Phosphorylated p53 species; phospho-p53(S15), phospho-p53(S46), and phospho-p53(S392) accumulated in MCF-7 cells indicating the potential of Cu8AqN to restore p53 function in the cells. In combination, the data indicates that Cu8AqN is a useful lead molecule worthy of further exploration as a potential anti-cancer drug.

Marine seaweed endophytic fungi-derived active metabolites promote reactive oxygen species-induced cell cycle arrest and apoptosis in human breast cancer cells.

Endophytic fungi have an abundant sources rich source of rich bioactive molecules with pivotal pharmacological properties. Several studies have found that endophytic fungi-derived bioactive secondary metabolites have antiproliferative, anti-oxidant, and anti-inflammatory properties, but the molecular mechanism by which they induce cell cycle arrest and apoptosis pathways is unknown. This study aimed to determine the molecular mechanism underlying the anticancer property of the endophytic fungi derived active secondary metabolites on human breast cancer cells. In this study, we identified four endophytic fungi from marine seaweeds and partially screened its phytochemical properties by Chromatography-Mass Spectrometry (GC-MS) analysis. Moreover, the molecular mechanism underlying the anticancer property of these active secondary metabolites (FA, FB, FC and FE) on human breast cancer cells were examined on MCF-7 cells by TT assay, Apoptotic assay by Acridine orang/Ethidium Bromide (Dual Staining), DNA Fragmentation by DAPI Staining, reactive oxygen species (ROS) determination by DCFH-DA assay, Cell cycle analysis was conducted Flow cytometry and the apoptotic signalling pathway was evaluated by westernblot analysis. Doxorubicin was used as a positive control drug for this experiment. The GC-MS analysis of ethyl acetate extract of endophytic fungi from the marine macro-algae revealed the different functional groups and bioactive secondary metabolites. From the library, we observed the FC (76%), FB (75%), FA (73%) and FE (71%) have high level of antioxidant activity which was assessed by DPPH scavenging assay. Further, we evaluated the cytotoxic potentials of these secondary metabolites on human breast cancer MCF-7 cells for 24h and the IC50 value were calculated (FA:28.62 ± 0.3µg/ml, FB:49.81 ± 2.5µg/ml, FC:139.42 ± µg/ml and FE:22.47 ± 0.5µg/ul) along with positive control Doxorubicin 15.64 ± 0.8µg/ml respectively by MTT assay. The molecular mechanism by which the four active compound induced apoptosis via reactive oxygen species (ROS) and cell cycle arrest in MCF-7 cells was determined H2DCFDA staining, DAPI staining, Acridine orange and ethidium bromide (AO/EtBr) dual staining, flowcytometry analysis with PI staining and apoptotic key regulatory proteins expression levels measured by westernblot analysis. Our findings, revealed the anticancer potential of endophytic fungi from marine seaweed as a valuable source of bioactive compounds with anticancer properties and underscore the significance of exploring marine-derived endophytic fungi as a promising avenue for the development of novel anticancer agents. Further investigations are necessary to isolate and characterize specific bioactive compounds responsible for these effects and to validate their therapeutic potential in preclinical and clinical settings.

Cyclizine induces cytotoxicity and apoptosis in macrophages through the extrinsic and intrinsic apoptotic pathways.

Cyclizine, an over-the-counter and prescription antihistamine, finds widespread application in the prevention and treatment of motion sickness, encompassing symptoms such as nausea, vomiting, dizziness, along with its effectiveness in managing vertigo. However, the overuse or misuse of cyclizine may lead to hallucinations, confusion, tachycardia, and hypertension. The molecular mechanisms underlying cyclizine-induced cytotoxicity and apoptosis remain unclear. During the 24 h incubation duration, RAW264.7 macrophages were exposed to different concentrations of cyclizine. Cytotoxicity was assessed through the lactate dehydrogenase assay. Flow cytometry employing annexin V-fluorescein isothiocyanate and propidium iodide was utilized to evaluate apoptosis and necrosis. Caspase activity and mitochondrial dysfunction were evaluated through a fluorogenic substrate assay and JC-1 dye, respectively. Flow cytometry employing fluorogenic antibodies was utilized to evaluate the release of cytochrome c and expression of death receptor, including tumor necrosis factor-α receptor and Fas receptor. Western blotting was utilized to evaluate the expression of the Bcl2 and Bad apoptotic regulatory proteins. The findings unveiled from the present study demonstrated that cyclizine exerted a concentration-dependent effect on RAW264.7 macrophages, leading to the induction of cytotoxicity, apoptosis, and necrosis. This compound further activated the intrinsic apoptotic pathway by inducing mitochondrial dysfunction, Bcl2/Bad exchange expression, cytochrome c liberation, and activation of caspases contained caspase 3, 8, and 9. Moreover, the activation of the extrinsic apoptotic pathway was observed as cyclizine induced the upregulation of death receptors and increased caspase activities. Based on our investigations, it can be inferred that cyclizine prompts cytotoxicity and apoptosis in RAW264.7 macrophages in a concentration-dependent manner by triggering both the intrinsic and extrinsic apoptotic pathways.

TSPO is a novel biomarker for prognosis that regulates cell proliferation through influencing mitochondrial functions in HCC

The disorder of mitochondrial functions plays a key role in oncogenesis. It is known that TSPO (18-kDa translocator protein) lies in a peculiar location at the interface between the mitochondria and the cytosol. TSPO is found in many types of tissues and is associated with multiple cellular processes, including apoptosis, cell proliferation and the regulation of mitochondria. However, the involvement of TSPO in hepatocellular carcinoma (HCC) remains unclear. In this study, we found that TSPO is upregulated in HCC tissue and is associated with poor differentiation and poor survival. Multivariate analyses showed that TSPO was an independent predictive factor for poor prognosis in HCC patients. For the first time, we provided evidence that TSPO knockdown suppressed HCC cell proliferation in vitro. Hence, TSPO knockdown-induced apoptosis by disturbing mitochondrial function by enhancing the formation of reactive oxygen species (ROS) and decreasing the mitochondrial membrane potential (ΔΨm). An assay exploring the underlying mechanism revealed that TSPO knockdown modulated apoptotic regulatory proteins by regulating the ERK signaling pathway. Through a functional assay and an in vivo mouse model, the anti-cancer effect of PK11195, a specific ligand of TSPO, on HCC was revealed. In summary, TSPO may potentially serve as a prognostic biomarker, and TSPO might be a potential therapeutic target for HCC.

The second-generation curcumin analogue RL71 elicits G2/M cell cycle arrest and apoptosis in canine osteosarcoma cells.

Canine osteosarcoma is an aggressive cancer, comprising 85% of canine bone neoplasms. Current treatment practices of surgery and chemotherapy increase 1-year survival by only 45%. The curcumin analogue RL71, has demonstrated potent in vitro and in vivo efficacy in several models of human breast cancer through increased apoptosis and cell cycle arrest. Thus, the present study aimed to investigate efficacy of curcumin analogues in two canine osteosarcoma cell lines. Osteosarcoma cell viability was assessed using the sulforhodamine B assay and mechanisms of action were determined by analysing the levels of cell cycle and apoptotic regulatory proteins via Western blotting. Further evidence was obtained using flow cytometry to detect cell cycle distribution and the number of apoptotic cells. RL71 was the most potent curcumin analogue with EC50 values of 0.64 ± 0.04 and 0.38 ± 0.009 μM (n = 3) in D-17 (commercial) and Gracie canine osteosarcoma cells, respectively. RL71 significantly increased the ratio of cleaved-caspase 3 to pro-caspase 3 and the level of apoptotic cells at the 2× and 5× EC50 concentration (p < 0.001, n = 3). Furthermore, at the same concentration, RL71 significantly increased the number of cells in the G2/M phase. In conclusion, RL71 has potent cytotoxic activity in canine osteosarcoma cells triggering G2/M arrest and apoptosis at concentrations achievable in vivo. Future research should further investigate molecular mechanisms for these changes in other canine osteosarcoma cell lines prior to in vivo investigation.

Gastroprotective effects of Polygonatum odoratum in rodents by regulation of apoptotic proteins and inflammatory cytokines

In an increasing interest in natural antiulcer compounds that may have gastric healing effects and possibly prevent ulcer recurrence, Polygonatum odoratum appears as a strong candidate. The gastroprotective potentials of P. odoratum rhizome extract (PORE) were explored on ethanol-induced gastric ulceration in rats. Sprague Dawley rats were caged in 5 groups, normal and ulcer control rats received CMC (1% carboxymethyl cellulose). Omeprazole (20 mg/kg) was given to reference Rats. Experimental rats were treated with 250 mg/kg and 500 mg/kg PORE, respectively. After an hour, the normal control rats received 1% CMC, whereas rat groups 2–5 were given absolute ethanol by oral gavage. After 60 min, rats received anesthesia and were sacrificed. Dissected gastric tissue was analyzed by histopathological and immunohistochemical techniques. PORE treatment significantly lowered the ethanol-induced gastric injury, as shown by up-surging gastric pH and mucus content, reduced leukocyte infiltration, lower ulcerative areas in mucosal layers, and increased antioxidants (SOD and CAT) and (MDA) levels. Furthermore, PORE pre-treated rats showed significantly increased expression of the Periodic acid-Schiff (PAS), HSP-70 protein, and decreased Bax protein in their gastric epithelial layers. PORE treatment showed an important regulation of inflammatory cytokines shown by decreasing the TNF-a, and IL-6 and increasing the IL-10 values. The detected biological activity of PORE is encouraging and presents the scientific evidence for its traditional use as a gastroprotection agent however further studies are required to determine the exact phytochemicals and mechanism pathway responsible for this bioactivity.

Concentration of Apoptotic Factors in Bronchoalveolar Lavage Fluid, as Potential Brain-Lung Oxygen Relationship, Correspond to the Severity of Brain Injury

The mechanism of acute brain injury initiates a cascade of consequences which can directly cause lung damage, and this can contribute to poor neurological outcomes. The aim of this study was to evaluate concentration of different apoptotic molecules in the bronchoalveolar lavage fluid (BALF) in patients after severe brain injury and to correlate them with selected clinical variables and mortality. Patients with brain injury receiving BALF operation were included in the study. BALF samples were collected within the first 6-8 hours after traumatic brain injury (A) and at days 3 (B) and 7 (C) after admission to the intensive care unit (ICU). Changes in the BALF nuclear-encoded protein (Bax), apoptotic regulatory protein (Bcl-2), pro-apoptotic protein (p53) and its upregulated modulator (PUMA), apoptotic protease factor 1 (APAF-1), Bcl-2 associated agonist of cell death (BAD) and caspase-activated DNase (CAD) were analysed. These values were correlated with the selected oxygenation parameters, Rotterdam computed tomography (CT) score, the Glasgow Coma Score and 28-day mortality. We found a significant increase in the concentration of selected apoptotic factors at admission (A), at day 3 (B) and day 7 (C) after severe brain damage contrasted with baseline level A (p < 0.001, separately). That concentration of selected apoptotic factors was significantly correlated with the severity of the injury and mortality. Activation of different apoptotic pathways seems to be an important process occurring in the lungs of patients in the early phases after severe brain trauma. Levels of apoptotic factors in the BALF correlates with the severity of brain injury.

Cilostazol attenuates oxidative stress and apoptosis in the quadriceps muscle of the dystrophic mouse experimental model.

Duchenne muscular dystrophy (DMD) is the most severe and frequent form of muscular dystrophy. The mdx mouse is one of the most widely used experimental models to understand aspects of the biology of dystrophic skeletal muscles and the mechanisms of DMD. Oxidative stress and apoptosis are present in early stages of the disease in mdx mice. The high production of reactive oxygen species (ROS) causes activation of apoptotic death regulatory proteins due to DNA damage and breakdown of nuclear and mitochondrial membranes. The quadriceps (QUA) muscle of the mdx mouse is a good tool to study oxidative events. Previous studies have demonstrated that cilostazol exerts an anti-oxidant effect by decreasing the production of reactive oxygen species (ROS). The present study aimed to evaluate the ability of cilostazol to modulate oxidative stress and apoptosis in the QUA muscle of mdx mice. Fourteen-day-old mdx mice received cilostazol or saline for 14 days. C57BL/10 mice were used as a control. In the QUA muscle of mdx mice, cilostazol treatment decreased ROS production (-74%), the number of lipofuscin granules (-47%), lipid peroxidation (-11%), and the number of apoptotic cells (-66%). Thus cilostazol showed anti-oxidant and anti-apoptotic action in the QUA muscle of mdx mice.

Chidamide: Targeting epigenetic regulation in the treatment of hematological malignancy.

Epigenetic alterations frequently participate in the onset of hematological malignancies. Histone deacetylases (HDACs) are essential for regulating gene transcription and various signaling pathways. Targeting HDACs has become a novel treatment option for hematological malignancies. Chidamide is the first oral selective HDAC inhibitor for HDAC1, HDAC2, HDAC3, and HDAC10 and was first approved for the treatment of R/R peripheral T-cell lymphoma by the China Food and Drug Administration in 2014. Chidamide was also approved under the name Hiyasta (HBI-8000) in Japan in 2021. In vitro studies revealed that chidamide could inhibit proliferation and induce apoptosis via cell cycle arrest and the regulation of apoptotic proteins. In clinical studies, chidamide was also efficacious in multiple myeloma, acute leukemia and myelodysplastic syndrome. This review includes reported experimental and clinical data on chidamide monotherapy or chidamide treatment in combination with chemotherapy for various hematological malignancies, offering a rationale for the renewed exploration of this drug.

Biosynthesized tin oxide-sodium alginate-polyethylene glycol-carvacrol nanocomposite shows anticancer activity on esophagus squamous carcinoma cells

Esophagus cancer is the sixth leading cause of cancer-related mortalities worldwide. In this study, we synthesized a biocompatible nanocomposite with green synthesized tin oxide using carvacrol, sodium allyl, and polyethylene glycol. Carvacrol is a phenolic monoterpenoid extracted from the essential oils of the plants belonging to the Lamiaceae family. Carvacrol possesses immense pharmacological properties such as antioxidant, antiviral, anticancer, etc. In this study, we assessed the efficacy of Tin oxide-Sodium alginate-Polyethylene glycol-Carvacrol (SnO2-SAPG-Carvacrol) nanocomposite. The synthesized nanocomposite was subjected to spectroscopic analysis, FTIR spectroscopic analysis, FESEM & EDAX analysis, TEM, and XRD & DLS analysis. The antimicrobial efficacy of SnO2-SAPG-Carvacrol nanocomposite against various microorganisms was analyzed using the disc diffusion method. MTT assay was performed to detect the cytotoxic effect of SnO2-SAPG-Carvacrol nanocomposite on KYSE-150–7 cells esophagus squamous carcinoma cell line. The apoptotic efficacy of SnO2-SAPG-Carvacrol nanocomposite was assessed with staining techniques such as DCFH-DA, Rhodamine 123 staining, and AO/EtBr staining. Oxidative stress markers were quantified to detect the anticancer property of SnO2-SAPG-Carvacrol nanocomposite. To analyze the anti-migratory effect we have done a transwell chamber assay. To confirm the anticancer potency of SnO2-SAPG-Carvacrol nanocomposite the cell cycle regulatory and apoptotic regulatory proteins were quantified. Characterization analysis of SnO2-SAPG-Carvacrol nanocomposite confirms it has a potent nanocomposite that can be utilized as a drug. MTT assay and staining results of SnO2-SAPG-Carvacrol nanocomposite treated KYSE-150–7 cells prove the apoptotic property of nanocomposite synthesized. SnO2-SAPG-Carvacrol nanocomposite treatment on KYSE-150–7 cells significantly increased oxidative stress thereby inducing apoptosis in KYSE-150–7 cells. The anti-migratory property of synthesized nanocomposite was confirmed with the transwell chamber assay. The ELISA results of cell regulatory and apoptotic regulatory protein confirm the anticancer activity of SnO2-SAPG-Carvacrol nanocomposite. Overall our results confirm that SnO2-SAPG-Carvacrol nanocomposite is a potent anticancer drug.

Synergistic effects of BAY606583 on docetaxel in esophageal cancer through modulation of ERK1/2.

Docetaxel (DTX) is a taxane chemotherapy agent used to treat many types of cancers, including esophageal squamous cell carcinoma. Adenosine is a purinergic signaling molecule that contributes to cancercellproliferation via A2B adenosine receptor (A2BAR) activation. Extracellular signal-regulated protein kinase (ERK) plays a crucial role in cell proliferation in various types of cancers. Stimulation of A2BAR involves a regulated ERK signaling pathway, and might provide a fascinating approach for treatment, leading to decreased proliferation in certain tumors that express A2BAR. Recent studies demonstrated that DTX and A2BAR have anticancer effects. The current study was designed to investigate the synergistic effect of the A2BAR agonist (BAY606583) on DTX in inducing antiproliferation effects on esophageal squamous cells carcinoma (ESCCs). The cell viability was assessed using the MTT assay in KYSE-30 and Ym-1 cells. In addition, the synergistic effect of DTX on the A2BAR agonist was evaluated. Subsequently, apoptosis was assessed by Annexin-V and propidium iodide staining, and Bcl-2, Bax, and ERK1/2 protein-level expressions were evaluated by Western blot. Use of BAY606583 and cotreatment of DTX and BAY606583 significantly decreased cell proliferation in KYSE-30 and Ym-1 cell lines. The use of BAY606583 and cotreatment of DTX with the A2BAR agonist induced apoptosis in KYSE-30 and Ym-1 cells. Western blot analysis revealed that the use of the A2BAR agonist and cotreatment of DTX with the A2BAR agonist inhibited the expression of apoptotic regulatory proteins as well as the expression of ERK1/2 proteins. Our findings suggested that use of BAY606583 and cotreatment of BAY606583/DTX have an antiproliferative effect on ESCC cell lines through ERK signaling pathway inhibition. BAY606583 has a synergistic effect on DTX, which could be used as an adjuvant for esophageal cancer therapy.

Anti-Protease Activity Deficient Secretory Leukocyte Protease Inhibitor (SLPI) Exerts Cardioprotective Effect against Myocardial Ischaemia/Reperfusion.

Inhibition of proteases shows therapeutic potential. Our previous studies demonstrated the cardioprotection by the Secretory Leukocyte Protease Inhibitor (SLPI) against myocardial ischaemia/reperfusion (I/R) injury. However, it is unclear whether the cardioprotective effect of SLPI seen in our previous works is due to the inhibition of protease enzymes. Several studies demonstrate that the anti-protease independent activity of SLPI could provide therapeutic benefits. Here, we show for the first time that recombinant protein of anti-protease deficient mutant SLPI (L72K, M73G, L74G) (mt-SLPI) could significantly reduce cell death and intracellular reactive oxygen species (ROS) production against an in vitro simulated I/R injury. Furthermore, post-ischaemic treatment of mt-SLPI is found to significantly reduce infarct size and cardiac biomarkers lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) activity, improve cardiac functions, attenuate I/R induced-p38 MAPK phosphorylation, and reduce apoptotic regulatory protein levels, including Bax, cleaved-Caspase-3 and total Capase-8, in rats subjected to an in vivo I/R injury. Additionally, the beneficial effect of mt-SLPI was not significantly different from the wildtype (wt-SLPI). In summary, SLPI could provide cardioprotection without anti-protease activity, which could be more clinically beneficial in terms of providing cardioprotection without interfering with basal serine protease activity.

Copper-imidazo[1,2-a]pyridines differentially modulate pro- and anti-apoptotic protein and gene expression in HL-60 and K562 leukaemic cells to cause apoptotic cell death

Despite the availability of a myriad targeted treatments, resistance and treatment failures remains common in cancer treatment. Moreover, the high cost of targeted antibodies excludes a large cohort of patients from their benefits. In this context, copper-imidazo[1,2-a]pyridines were evaluated as alternative drug candidates against two common leukaemias, represented by HL-60 and K562 cells. A previous study identified JD88(21), JD47(29) and JD49(28) to be active against these cell lines with IC50 values between 1.9 and 6 μM and low leukocyte toxicity. To better understand their mechanism of action, their mode of cell death, effects on expression of apoptotic regulatory proteins and their respective genes were investigated. In both cell lines, the copper-imidazo[1,2-a]pyridines, at IC75 concentrations, caused membrane blebbing, raised phosphatidyl-serine levels on cell membranes and increased caspase-3 activity. A loss of mitochondrial membrane potential and activation of caspase-9, combined with poor caspase-8 activity indicated activation of intrinsic apoptosis. Apoptotic proteome analysis showed that the copper-imidazo[1,2-a] pyridines elevated protein levels of pro-apoptotic Bax and Smac/DIABLO in both cell lines, confirming their importance in apoptotic cell death. Conversely, though survivin was increased, this was counteracted by high levels of HTRA2/Omi expression. Effects on apoptotic regulatory proteins Bad, Bcl-2, XIAP and cIAP-1 was inconsistent between the copper-imidazo[1,2-a]pyridines and between the two cell lines, suggesting that the effect of the complexes was modulated by the molecular signature of each cell line. Analysis of mRNA transcripts showed a poor correlation between mRNA levels and associated proteins, implying that copper-imidazo[1,2-a]pyridines compromised protein synthesis and degradation.

Neuroprotective Effects of Sodium Butyrate through Suppressing Neuroinflammation and Modulating Antioxidant Enzymes.

The discovery of effective therapeutic agents against neurodegenerative diseases (NDDs) remains challenging. Neurotoxicity, inflammations, and oxidative stress are associating factors of NDDs. Sodium butyrate (NaB) is a short-chain fatty acid found in diet and produced in the gut that reportedly protects cancer, inflammation, obesity and so on. Previously, SH-SY5Y cells were studied as in vitro models of cerebral diseases. We have investigated the neuroprotective effects of NaB in SH-SY5Y cells stimulated with TNF-α. The expression of inflammatory mediators, including iNOS, COX-2, and mitogen-activated protein kinases (MAPK) and the apoptotic regulators, including P-53, Bcl-2 associated X (BAX) Protein, and caspase-3 were analyzed by western blot analysis. The anti-apoptotic gene Bcl-2 and the pro-apoptotic gene BAX translocation were also investigated. Our results showed that NaB attenuated cell death and inhibited the NO production and decreased the expression of iNOS and COX-2 in TNF-α-stimulated SH-SY5Y cells. NaB notably ameliorated apoptotic regulatory proteins p-53, Caspase-3 and caspase-1 level, and reversed phosphorylation of extracellular signal-regulated kinases and p-38 proteins. NaB ameliorated Glucocorticoid receptor and NLRP3 inflammasome expressions. NaB also suppressed the BAX nuclear translocation and modulated Nrf-2, HO-1 and MnSOD expression in neuroblastoma cells. In addition, NaB substantially reversed the reactive oxygen species in H2O2 induced SH-SY5Y cells. Altogether, our results suggest that sodium butyrate has potential therapeutic effects against NDDs.

Hippocampal Degeneration and Behavioral Impairment During Alzheimer-Like Pathogenesis Involves Glutamate Excitotoxicity.

The hallmarks of Alzheimer's disease (AD) pathology include senile plaques accumulation and neurofibrillary tangles, which is thought to underlie synaptic failure. Recent evidence however supports that synaptic failure in AD may instead be instigated by enhanced N-methyl-D-aspartate (NMDA) activity, via a reciprocal relationship between soluble amyloid-β (Aβ) accumulation and increased glutamate agonist. While previous studies have shown Aβ-mediated alterations to the glutamatergic system during AD, the underlying etiology of excitotoxic glutamate-induced changes has not been explored. Here, we investigated the acute effects of stereotaxic dentate gyrus (DG) glutamate injection on behavior and molecular expression of specific proteins and neurochemicals modulating hippocampal functions. Dependence of glutamate-mediated effects on NMDA receptor (NMDAR) hyperactivation was tested using NMDARs antagonist memantine. DG of Wistar rats (12-weeks-old) were bilaterally microinjected with glutamate (500mM) with or without daily intraperitoneal (i.p.) memantine injection (20mg/kg) for 14days, while controls received either intrahippocampal/i.p. PBS or i.p. memantine. Behavioral characterization in open field and Y-maze revealed that glutamate evoked anxiogenic responses and perturbed spatial memory were inhibited by memantine. In glutamate-treated rats, increased NO expression was accompanied by marked reduction in profiles of glutathione-s-transferase and glutathione peroxidase. Similarly, glutamate-mediated increase in acetylcholinesterase expression corroborated downregulation of synaptophysin and PSD-95, coupled with initiation of reactive astrogliosis (GFAP). While neurofilament immunolocalization/immunoexpression was unperturbed, we found glutamate-mediated reduction in neurogenic markers Ki67 and PCNA immunoexpression, with a decrease in NR2B protein expression, whereas mGluR1 remains unchanged. In addition, increased expression of apoptotic regulatory proteins p53 and Bax was seen in glutamate infused rats, corroborating chromatolytic degeneration of granule neurons in the DG. Interestingly, memantine abrogated most of the degenerative changes associated with glutamate excitotoxicity in this study. Taken together, our findings causally link acute glutamate dyshomeostasis in the DG with development of AD-related behavioral impairment and molecular neurodegeneration.

Novel Phenylmethylenecyclohexenone Derivatives as Potent TrxR Inhibitors Display High Antiproliferative Activity and Induce ROS, Apoptosis, and DNA Damage.

The natural product piperlonguminine (PL) has been shown to exert potential anticancer activity against several types of cancer via elevation of reactive oxidative species (ROS). However, the application of PL has been limited due to its poor water solubility and moderate activity. To improve PL's potency, we designed and synthesized a series of 17 novel phenylmethylenecyclohexenone derivatives and evaluated their pharmacological properties. Most of them exerted antiproliferative activities against four cancer cell lines with IC50 values lower than PL. Among these, compound 10 e not only showed good water solubility and exerted the most potent antiproliferative activity against HGC27 cells (IC50 =0.76 μM), which was 10-fold lower than PL (IC50 =7.53 μM), but also exhibited lower cytotoxicity in human normal gastric epithelial cells GES-1 compared with HGC27 cells. Mechanistically, compound 10 e inhibited thioredoxin reductase (TrxR) activity, increased ROS levels, and diminished mitochondrial transmembrane potential (MTP) in HGC27 cells. Furthermore, 10 e also induced G2 /M cell-cycle arrest, and triggered cancer cell apoptosis through the regulation of apoptotic proteins. Finally, 10 e promoted DNA damage in HGC27 cells via the activation of the H2AX(S139ph) and p53 signaling. In conclusion, 10 e, with prominent tumor selectivity and water solubility, could be a promising candidate for the treatment of cancer and, as such, warrants further investigation.

Notoginsenoside R1 attenuates sevoflurane-induced neurotoxicity.

BackgroundSevoflurane, a volatile anesthetic, is known to induce widespread neuronal degeneration and apoptosis. Recently, the stress-inducible protein sestrin 2 and adenosine monophosphate-activated protein kinase (AMPK) have been found to regulate the levels of intracellular reactive oxygen species (ROS) and suppress oxidative stress. Notoginsenoside R1 (NGR1), a saponin isolated from Panax notoginseng, has been shown to exert neuroprotective effects. The effects of NGR1 against neurotoxicity induced by sevoflurane were assessed.MethodsSprague-Dawley rat pups on postnatal day 7 (PD7) were exposed to sevoflurane (3%) anesthesia for 6 h. NGR1 at doses of 12.5, 25, or 50 mg/kg body weight was orally administered to pups from PD2 to PD7.ResultsPretreatment with NGR1 attenuated sevoflurane-induced generation of ROS and reduced apoptotic cell counts. Western blotting revealed decreased cleaved caspase 3 and Bad and Bax pro-apoptotic protein expression. NGR1 substantially upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) expression along with increased heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase-1 levels, suggesting Nrf2 signaling activation. Enhanced sestrin-2 and phosphorylated AMPK expression were noticed following NGR1 pretreatment.ConclusionThis study revealed the neuroprotective effects of NGR1 through effective suppression of apoptosis and ROS via regulation of apoptotic proteins and activation of Nrf2/HO-1 and sestrin 2/AMPK signaling cascades.

Expression of Bax and Bcl-2 Apoptotic Regulatory Proteins in Melphalan-induced Spermatogenic Dysfunction

The adverse effect of Melphalan (MEP), an anti-cancer compound in the male reproductive system, was investigated. In this study, 1, 3, or 5 mg/kg/bwt intraperitoneal doses of MEP were administered daily for 28 days. Half of the mice were sacrificed after 24 hours of the last treatment, and the other half were sacrificed 28 days after withdrawal of treatment. Glutathione peroxidase (GPX), glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD), reactive oxygen species (ROS) and lipid peroxidation (LPO) levels of testicular tissue were evaluated. The induction of apoptosis was assessed by investigating the level of CASP-3 and CASP-9 activities in spermatogenic cells. CASP- 9, Bax and BCL-2 expression were checked by real-time PCR and western blotting. Testis weight in MEP-treated mice was significantly decreased. There was a significant decrease in sperm parameters, GSH GPx, CAT, and SOD levels, with a concomitant increase in ROS and MDA levels confirming the generation of oxidative stress. MEP-treatment leads to the increased expression of CASP-9, BAX, with decreased BCL-2 protein levels in a dosedependent manner. No significant recovery after 28 days of withdrawal of the treatment was observed. The results indicate that MEP- treatment leads to testicular damage due to the formation of oxidative stress and induction of caspase-dependent apoptosis.

Chlorogenic acid inhibits growth of 4T1 breast cancer cells through involvement in Bax/Bcl2 pathway.

Chlorogenic acid is an herbal compound with various effects such as antiviral, antioxidant, and anticancer effect with low toxicity, which inhibits cell proliferation. Clinical studies had shown that chlorogenic acid has a positive effect on the different types of cancers treatment. Hence, this study evaluates chlorogenic acid effects on 4T1 breast cancer cells. In this study, cell proliferation was measured using an 3-(4,5-methylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay (MTT) on 4T1 cells. Afterwards, other assays like P53, Caspase-3 proteins expression and Annexin V/PI were detected by flow cytometry. Also; Bax and Bcl-2 were carried out by immunocytochemistry. 200 μM of chlorogenic acid concentration showed the highest level of cytotoxicity toward 4T1 cells. Percentage of cell viability data were significant in 100 μM (P < 0.05) and 150, 200 μM (P < 0.001) doses. The evaluation using Annexin V/PI showed cell apoptosis in 100 μM (P < 0.05), 150 μM (P < 0.01), and for 200 μM (P < 0.05 and P < 0.01). Immunocytochemistry results showed the upregulation of Bax and also the downregulation of Bcl-2 in 4T1 cells treated with chlorogenic acid (P < 0.001). The expression level of P53 and caspase-3 increased during treatment with chlorogenic acid in the 4T1 cells (P < 0.001). Our findings demonstrated that chlorogenic acid plays a notable role on apoptosis inducing in the 4T1 cells through regulation of apoptotic proteins.

Evaluation of lymphocyte apoptosis in patients with oral cancer.

Objectives To evaluate apoptotic levels of peripheral blood mononuclear cells (PBMCs) and apoptotic regulatory proteins (Bax and Bcl-2) in lymphocyte subsets of oral cancer (OC) patients and healthy controls (HC).Methodology The percentage of apoptotic cells and lymphocyte counts were measured in the first cohort using PBMCs obtained from 23 OC patients and 6 HC. In the second cohort, (OC, 33; HC, 13), the mean fluorescence intensity (MFI) of Bax and Bcl-2 in CD19+ B, CD4+ T, CD8+ T, and CD16+56+ natural killer (NK) cells was determined via flow cytometry.Results The percentage of apoptotic cells was higher in the PBMCs of OC patients than in HC patients, particularly in patients with stage IV cancer (p<0.05). However, lymphocyte counts were significantly lower in stage IV patients (p<0.05). NK CD19+ B and CD16+56+ cell counts were significantly lower in OC patients compared with HC patients (p<0.001 and p<0.01, respectively), but CD4+ T cells were interestingly significantly higher in OC patients (p<0.001). While Bax MFI was slightly higher, Bcl-2 MFI was significantly lower for all four lymphocyte subsets in OC samples, particularly in stage IV patients, when compared with HC. Consequently, Bax/Bcl-2 ratios showed an upward trend from HC to OC patients, particularly those in stage IV. We found similar trends in Bax and Bcl-2 MFI for tumor stage, tumor size, and lymph node involvement.Conclusions The increased lymphocyte apoptosis in stage IV OC patients may be related to higher Bax levels and lower Bcl-2 levels. The Bax/Bcl-2 ratio in lymphocytes may be useful to determine the prognosis of OC patients, and could be considered a mean for supportive treatment in the future.