Evaluating the effect of alpha-mangostin on neural toxicity induced by acrylamide in rats

Acrylamide (ACR) is known to be a neurotoxic agent for humans and animals that has many applications in industry. Alpha-mangostin is a natural antioxidant that is extracted from mangosteen. This study aimed to investigate the protective effects of alpha-mangostin against ACR-induced neurotoxicity in rats and PC12 cells. Male Wistar rats were used in this investigation for 11 days, divided into 8 groups: 1. control group (normal saline), 2. ACR (50 mg/kg, i.p.), 3-6. ACR + alpha-mangostin (20, 40, 60 mg/kg, p.o.), 7. ACR + vitamin E (200 mg/kg, i.p., every other day) 8. alpha-mangostin (60 mg/kg, p.o.). On the last day of the study, the behavioral test was performed. The amounts of malondialdehyde (MDA) and glutathione (GSH) were measured. Also, the effects of ACR and alpha-mangostin were assessed by MTT assay on PC12 cells, and the levels of reactive oxygen species (ROS), B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), and cleaved caspase-3 proteins were measured by Western blotting. Receiving ACR caused motor disorders in animals, increased MDA, and decreased GSH levels of the cerebral cortex versus the control group. Alpha-mangostin (60 mg/kg) reduced ACR motility disorders, MDA amounts, and augmented GSH levels. The concurrent administration of vitamin E and ACR reduced gait score, MDA level, and amplified GSH content versus the ACR group. In the in vitro section, alpha-mangostin (1.25 µM, 24 h) increased cell viability, attenuated ROS, Bax/Bcl-2, and cleaved caspase-3 levels versus the ACR group. Alpha-mangostin reduced the toxicity of ACR by inhibiting oxidative stress and apoptosis. Therefore, it could be a promising compound for managing ACR-induced neurotoxicity.

The ototoxic drug cisplatin localises to stress granules altering their dynamics and composition

Cisplatin is an effective platinum-based chemotherapeutic with several side effects, including ototoxicity. Cochlear cells have low rates of proliferation yet are highly susceptible to cisplatin. We hypothesized that cisplatin ototoxicity may be caused by cisplatin-protein interactions rather than cisplatin-DNA interactions. Two known cisplatin-binding proteins are involved in the stress granule (SG) response. SGs are a pro-survival mechanism involving formation of transient ribonucleoprotein complexes during stress. We examined the effects of cisplatin on SG dynamics and composition in cell lines derived from the cochlea and retinal pigment epithelium. Cisplatin-induced SGs are significantly diminished in size and quantity compared to arsenite-induced SGs and are persistent after 24 hours recovery. Additionally, cisplatin pre-treated cells were unable to form a typical SG response to subsequent arsenite stress. Cisplatin-induced SGs had significant reductions in the sequestration of eIF4G and proteins RACK1 and DDX3X. Live cell imaging of cisplatin-TR revealed localisation to SGs and retention for at least 24 hours. We show cisplatin-induced SGs have impaired assembly, altered composition and are persistent, providing evidence of an alternate mechanism for cisplatin-induced ototoxicity via an impaired SG response.

The invalidity of and Alternative to Linear Quadratic Model as a Predictive Model for Post-Irradiation Cell Survival

The linear-quadratic (LQ) model has been the dominant tool in preclinical radiobiological modeling of cell survival as a function of dose. However, as a second-order polynomial approximation, it suffers from two well-known pitfalls: non-monotonic behavior and poor extrapolation. This study examined the raw data of 253 sets of photon and 943 sets of the ion beam from the Particle Irradiation Data Ensemble (PIDE) project to understand how often the LQ model could result in a negative β, which would give unrealistic predictions. Additionally, the predictive performance of the LQ model, the power model, and the linear models' predictive performance was studied using leave-one-out cross-validation (LOOCV) and 2-fold cross-validation. It was found that when fitted to the LQ model, 7.5% of the photon and 29.8% of the ion beam dose-response data would result in negative β, compared to 0.77% and 2.0% reported in the literature. The LQ model performed poorly in LOOCV compared to the alternative power model, and performed the worst among the three models in 2-fold cross-validation. The LQ model leads to unrealistic parameters, which are vastly under-reported in the literature, and performs poorly in standard cross-validation tests. Therefore, the LQ model is not a valid predictive dose-response model for cell survival. Alternative models need to be investigated.

Induction of Caspase-dependent Apoptosis in Rat Bone Marrow Mesenchymal Stem Cells due to Di-2-Ethylhexyl Phthalate Toxicity was found to arrest the Cell Cycle at the G1 stage

BACKGROUND

Di-(2-ethylhexyl) phthalate) DEHP) is used as a plasticizer in polyvinyl chloride products which is widely utilized. Previously we found, DEHP reduced the viability and proliferation ability of bone marrow mesenchymal stem cells (BMSCs).

OBJECTIVE

In the present study, the mechanism of DEHP toxicity was investigated.

METHODS

Rat BMSCs were cultured up to 3rd passage and their viability was determined after treatment with 100 and 500 μM of DEHP for 24 and 48 hours. The levels of sodium, potassium, and calcium as well as induction of apoptosis were investigated. Using flow cytometry, cell cycle analysis was performed and the expression of genes involved in the cell cycle was evaluated using reverse transcriptase-PCR. Data were analyzed and p<0.05 was taken as the level of significance.

RESULTS

Although the viability and electrolyte level of BMSCs were not affected with 100 μM of DEHP, this environmental pollution induced caspase-dependent apoptosis in a concentration-dependent manner. In both of the concentrations, DEHP arrests the cell cycle at the G0/G1 phase, and the expression of Cdk2 and Cdk4 was significantly reduced whereas an over-expression of P53 was observed. However, the expression of the raf1 gene remained unchanged.

CONCLUSION

DEHP induces caspase-dependent apoptosis in BMSCs and arrests the cell cycle due to the reduction of Cdk2 and Cdk4 expression via over-expression of P53.

A positive feedback loop of heparanase/syndecan1/nerve growth factor regulates cancer pain progression

Background

The purpose of this research was to assess the role of heparanase (HPSE)/syndecan1 (SDC1)/nerve growth factor (NGF) on cancer pain from melanoma.

Methods

The influence of HPSE on the biological function of melanoma cells and cancer pain in a mouse model was evaluated. Immunohistochemical staining was used to analyze HPSE and SDC1. HPSE, NGF, and SDC1 were detected using western blot. Inflammatory factors were detected using ELISA assay.

Results

HPSE promoted melanoma cell viability, proliferation, migration, invasion, and tumor growth, as well as cancer pain, while SST0001 treatment reversed the promoting effect of HPSE. HPSE up-regulated NGF, and NGF feedback promoted HPSE. High expression of NGF reversed the inhibitory effect of HPSE down-regulation on melanoma cell phenotype deterioration, including cell viability, proliferation, migration, and invasion. SST0001 down-regulated SDC1 expression. SDC1 reversed the inhibitory effect of SST0001 on cancer pain.

Conclusions

The results showed that HPSE promoted melanoma development and cancer pain by interacting with NGF/SDC1. It provides new insights to better understand the role of HPSE in melanoma and also provides a new direction for cancer pain treatment.

[Antiproliferative, apoptotic, and antimigratory activities of kafirins on cervical cancer-derived cell lines]

Background

Cervical cancer is one of the leading causes of death in women worldwide, both in developed and developing countries. Therefore, effective treatment of cervical cancer with potential anti-tumor drugs is important. However, new treatments inspired by nutritional medicine are needed.

Objective

To use the human cervical cancer cell lines HeLa and SiHa to evaluate the antiproliferative, apoptotic, and migratory activity of sorghum (kafirins).

Materials and methods

The anticancer effects of the kafirins were examined by counting cells, MTT assays, apoptosis, and migration assays.

Results

This investigation showed that sorghum induced growth inhibition of HeLa and SiHa cells at a significant level. The growth inhibition is dose-dependent and irreversible. When HeLa and SiHa cells were treated with sorghum due to the activity of kafirins, morphological changes were observed, which were identified through the formation of apoptopic bodies. And the kafirins at concentrations of 37.5, 75, 150, and 300 μg/mL decreased the migration of HeLa cells and SiHa cells.

Conclusion

This paper demonstrates the induction of antiproliferative, apoptotic, and anti-migratory activity in HeLa and SiHa cells by kafirins. Sorghum may be used as a nutraceutical with potential cancer-prevention benefits.

Antinociceptive, anti-inflammatory, and cytotoxic properties of Origanum vulgare essential oil, rich with β-caryophyllene and β-caryophyllene oxide

Background

Essential oils are of great interest for their analgesic and anti-inflammatory properties. We aimed to study the content of the essential oil of the Origanum vulgare of the Armenian highlands (OVA) in different periods of vegetation and to investigate its antinociceptive and anti-inflammatory effects in mice (in vivo) and cytotoxic action in cultured cells (in vitro). OVA essential oil was extracted from fresh plant material by hydro-distillation.

Methods

For OVA essential oil contents determination the gas chromatography-mass spectrometry method was used. Formalin and hot plate tests and analysis of cell viability using the methyl-thiazolyl-tetrazolium (MTT) assay were used.

Results

The maximal content of β-caryophyllene and β-caryophyllene oxide in OVA essential oil was revealed in the period of blossoming (8.18% and 13.36%, correspondently). In the formalin test, 4% OVA essential oil solution (3.5 mg/mouse) exerts significant antinociceptive and anti-inflammatory effects (P = 0.003). MTT assay shows approximately 60% cytotoxicity in HeLa and Vero cells for 2.0 μL/mL OVA essential oil in media.

Conclusions

The wild oregano herb of Armenian highlands, harvested in the blossoming period, may be considered as a valuable source for developing pain-relieving preparations.

Isolation and Characterization of Crab Haemolymph Exosomes and Its Effects on Breast Cancer Cells (4T1)

OBJECTIVE

The use of animal or plant exosomes in cancer treatment is promising because of their easy access and low cost. Freshwater crabs are used in traditional Iranian medicine to treat cancer. This study aims to determine the anti-cancer properties of exosomes removed from freshwater crabs on a breast cancer cell line (4T1) compared to bone marrow mesenchymal stem cells (BMSCs).

MATERIALS AND METHODS

In this experimental study, crab haemolymph exosomes were isolated via the precipitation method and characterised by electron microscopy, dynamic light scattering (DLS), and Western blot analysis. The protein concentration and total antioxidant capacity of these exosomes were determined by bicinchoninic acid (BCA) and cupric reducing antioxidant capacity (CUPRAC). The 4T1 cells and BMSCs were treated with exosomes and we assessed the cell survival by the resazurin and MTT assays. The level of nitric oxide (NO) secretion from the 4T1 cells was determined after treatment with the exosomes.

RESULTS

Electron microscopy, DLS and Western blot for CD63 confirmed that the isolated exosomes were <100 nm in size and expressed CD63. The total antioxidant capacity in these exosomes was 1.003 μM/ml and the protein concentration was 650 mg/ml. Resazurin and MTT assay results showed a decrease in survival of the 4T1 cells (P≤0.001) after treatment with the exosomes compared to cell growth in the exosome-treated BMSCs.

CONCLUSION

Crab haemolymph contains protein-rich exosomes with antioxidant activities that can have anti-cancer effects on 4T1 cells. These exosomes may be proposed for breast cancer therapeutics.

High anticancer efficacy of solid lipid nanoparticles containing Zataria multiflora essential oil against breast cancer and melanoma cell lines

Background

The cancer burden is rising rapidly worldwide, and it annually causes about 8.8 million deaths worldwide. Due to chemical drugs’ side effects and the emergence of resistance, the development of new green drugs has received much attention. We aimed to investigate whether solid-lipid nanoparticles containing essential oil of Zataria multiflora (ZMSLN) enhanced the anticancer efficacy of the essential oil against breast cancer (MDA-MB-468) and melanoma (A-375) cells.

Results

ZMSLN was prepared by the high-pressure homogenizer method; particle size 176 ± 8 nm, polydispersity index 0.22 ± 0.1, entrapment efficiency 67 ± 5%. The essential oil showed a dose-dependent antiproliferative effect on MDA-MB-468 and A-375 cells at all examined concentrations (75, 150, 300, 600, and 1200 μg/mL). Interestingly, after treating both cells with 75 μg/mL of ZMSLN, their viabilities were reduced to under 13%.

Conclusion

The finding showed that ZMSLN had a distinct antiproliferative efficacy; it could thus be considered a green anticancer candidate for further in vivo and in vivo studies.

Phototherapy and Sonotherapy of Melanoma Cancer Cells Using Nanoparticles of Selenium-Polyethylene Glycol-Curcumin as a Dual-Mode Sensitizer

Background:

As an alternative form of cancer therapy, photothermal therapy (PTT) and sonodynamic therapy (SDT) using nanomaterials are in development. Nanomaterials can act as energy absorber as well as anti-cancer agent.

Objective:

In this study, the effects of laser and ultrasound irradiation with Se-PEG-Cur nanoparticles were investigated on melanoma cancer.

Material and Methods:

In this experimental study, nanoparticles of selenium-polyethylene glycol-curcumin (Se-PEG-Cur) were synthesized, and their UV-vis absorption, particle size, zeta potential and photothermal conversion efficiency were determined. Se-PEG-Cur was then introduced as a novel 808-nm laser light absorbing agent as well as ultrasound (US) wave for treatment of C540 (B16/F10) cancer cells. Also, ROS generation in C540 (B16/F10) cancer cells was measured upon PTT and SDT using Se-PEG-Cur.

Results:

Mean size, zeta potential and photothermal conversion efficiency of Se-PEG-Cur were obtained as ~300 nm, 42.7 mV and 16.7%, respectively. Cell viability upon irradiation of the laser light or US waves with 100 µg mL^-1 Se-PEG-Cur were decreased to 33.9 and 22.9%, respectively.

Conclusion:

Intracellular ROS detection indicated that dual PTT and SDT in the presence of Se-PEG-Cur induced the highest ROS production. Se-PEG-Cur was therefore introduced as an absorbing agent of both laser light and US waves for cancer treatment.

The Multifaceted Roles of the Tumor Susceptibility Gene 101 (TSG101) in Normal Development and Disease

The multidomain protein encoded by the Tumor Susceptibility Gene 101 (TSG101) is ubiquitously expressed and is suggested to function in diverse intracellular processes. In this review, we provide a succinct overview of the main structural features of the protein and their suggested roles in molecular and cellular functions. We then summarize, in more detail, key findings from studies using genetically engineered animal models that demonstrate essential functions of TSG101 in cell proliferation and survival, normal tissue homeostasis, and tumorigenesis. Despite studies on cell lines that provide insight into the molecular underpinnings by which TSG101 might function as a negative growth regulator, a biologically significant role of TSG101 as a tumor suppressor has yet to be confirmed using genuine in vivo cancer models. More recent observations from several cancer research teams suggest that TSG101 might function as an oncoprotein. A potential role of post-translational mechanisms that control the expression of the TSG101 protein in cancer is being discussed. In the final section of the review, we summarize critical issues that need to be addressed to gain a better understanding of biologically significant roles of TSG101 in cancer.

Cytotoxicity and Effects of a New Cacium Hydroxide Nanoparticle Material on Production of Reactive Oxygen Species by LPS-Stimulated Dental Pulp Cells

Introduction

The aim of this study was to synthesize and characterize calcium hydroxide (CH) nanoparticles [CH-NP] and compare the cytotoxicity of these materials with that of mineral trioxide aggregate (White MTA) in human dental pulp mesenchymal cells (hDPMCs) stimulated by lipopolysaccharide (LPS).

Methods and Materials

The CH-NP were synthesized by the co-precipitation method, and the physical properties were investigated through X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive x-ray spectrometry (EDS). LPS-stimulated hDPMCs were placed in contact with different dilutions of culture media previously exposed to CH-NP and white MTA for 24 h. The groups were tested for cell viability by MTT formazan and Alamar Blue assays, the production of nitric oxide (NO) by Griess method and the production of reactive oxygen species (ROS) by means of the fluorescent oxidant-sensing probe 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA). Control groups for viability test were maintained in DMEM (not LPS-stimulated). For NO and ROS production, negative control group was cells in DMEM, and positive control was cells stimulated by LPS. The results were statistically analyzed by two-way ANOVA, Tukey's test and Dunnett's test (ɑ=0.05).

Results

The results showed that the cell viability remained above 50% in all materials, independent of the dilution in MTT formazan and Alamar Blue tests. MTA showed a reduction in NO production at dilutions of 1:4 to 1:32 compared with the positive control group (P<0.05). The tested materials exhibited lower ROS production by DPMCs than that by cells in the positive control group (P<0.05), and similar ROS production to the negative control group (P>0.05).

Conclusion

The outcomes of present in vitro study showed that MTA and [CH-NP] were not cytotoxic materials, with MTA closer to the results of control group (DMEM). MTA and [CH-NP] reduced ROS production at basal levels, with MTA inhibiting NO production at higher dilutions.

Cell Suspension Culture of Plumbago europaea L. Towards Production of Plumbagin

BACKGROUND

Plumbagin is as an important bioactive secondary metabolite found in the roots of Plumbago spp. The only one species, Plumbago europaea L., grows wild in Iran. The therapeutic use of plumbagin is limited due to its insufficient supply from the natural sources as the plants grow slowly and take several years to produce quality roots.

OBJECTIVES

To develop an efficient protocol for the establishment of callus and cell suspension cultures of P. europaea and to evaluate production of plumbagin in callus and cell suspension cultures of P. europaea for the first time.

MATERIAL AND METHODS

Stems and leaves explants were cultured on agar solidified (7% w/v) MS media, supplemented with different combination of 2, 4-D and Kin or 6-Benzylaminopurin (BA) for callus induction. The rapid growing calli were cultured in liquid Murashige and Skoog (MS) media in agitated condition for establishing cell suspension cultures of P. europaea. Moreover, the effects of light and dark conditions on the cell growth, cell viability and plumbagin production in cell suspension cultures of P. europaea were assessed.

RESULTS

Friable calli were successfully induced using stem segments of P. europaea in semisolid MS medium supplemented with 1 mg.L-1 2, 4-Dichlorophenoxy acetic acid (2, 4-D) and 0.5 mg.L-1of kinetin (Kin). Optimal cell growth was obtained when the cells were grown in MS liquid media supplemented with 1 mg.L-1 2, 4-D and 0.5 mg.L-1 kinetin with an initial cell density of ~3×105 cells per ml incubated in the dark at 25 ± 1 °C. Growth curve revealed that the maximum cell growth rate (14.83×105 cells per ml) achieved on the day 18 and the highest plumbagin content (0.9 mg.g-1 Dry Cell Weight (DCW)) in the cells was obtained at the late exponential phase under dark condition which determined by High Performance Liquid Chromatography (HPLC) technique. Based on the obtained results, cell viability remained around 82.73% during the 18 days of cell culture in darkness. These suspension cultures showed continuous and stable production of plumbagin.

CONCLUSIONS

Our study suggests that cell suspension cultures of P. europaea represent an effective system for biosynthesis and production of plumbagin as a valuable bioactive compound.

Preparation and Evaluation of A Novel Liposomal Nano-Formulation in Metastatic Cancer Treatment Studies

Objective

Today, in clinical trials, we suffer from the lack of effective methods with minimal side effects to deliver medication. Thus, efforts to identify better conditions for delivery of biomedical drugs seem necessary. The purpose of this study was to design a new liposomal formula for transportation of microRNA in osteosarcoma.

Materials and Methods

In this experimental study, several liposomal formulations were synthesized. Physical and chemical parameters, including size, zeta potential, polydispersity index, long-term stability of the liposomal-microRNA complex and the amount of miR-143 loading in liposome based nano-vesicles were optimized using different techniques. Similarly, the effect of free and encapsulated microRNA toxicity were investigated and compared in a human bone osteosarcoma cell line, named SaOs-2.

Results

In this study, we could produce a novel and optimized formulation of cationic PEGylated liposomal microRNA for gene delivery. The present synthesized microRNA lipoplex system was non-agglomerated. The system remained stable after four months and miR-143 leakage was not observed by performing gel electrophoresis. The microRNA lipoplex could enhance conduction of the loaded miR-143, and it also showed good biocompatibility to the healthy cells.

Conclusion

The PEGylated microRNA lipoplex system had a high potential for the systematic migration of miR-143 and it could improve intracellular stability of the released microRNA.

Effect of Pressure Stresses on Cell Viability and Protein Expression of Fascial Fibroblast

Background

Many physical and mechanical phenomena occur during the acupuncture and tuina regime, and pressure is one of the most basic mechanical phenomena.

Objectives

To understand the cellular bio-physical mechanism of basic mechanical stimulation via acupuncture and tuina by investigating the effect of different in vitro pressures on the cell viability and protein expression differences that originate from the facial fibroblasts around the meridians.

Materials and Methods

In vitro culture of the facial fibroblasts around the meridians was conducted using different pressures to perform single and multiple stimulation(s) on the cells. Thus, the changes in the fibroblast cell viability (cell viability rate and diameter) were tested, and changes in the fibroblast protein expression were observed.

Results

We found that the pressure stimulation may excite the fascial fibroblast viability at the acupoint and increase cell viability. Two interactive factors are involved: the pressure intensity and the number of pressure stimulations. In addition, we found that all three pressures lead to significant regulation effects on the protein expression of the meridian-related fascial tissue fibroblasts, and clustering analysis revealed that 100 kPa pressure stimulation exhibits the most evident effect on the protein expression which is the pressure inducing the most differentiated protein expression.

Conclusions

During the in vitro pressure process, the difference in the cell viability rate and protein expression of the facial fibroblasts around the meridians may (from a cell mechanics’ point-of-view) reveal the cytobiological and therapeutic mechanism of the basic mechanical stimulation via acupuncture and tuina on the facial fibroblasts around the meridians.

Sodium Nitroprusside Changed The Metabolism of Mesenchymal Stem Cells to An Anaerobic State while Viability and Proliferation Remained Intact

Objective

We used sodium nitroprusside (SNP), a nitric oxide (NO) releasing molecule, to understand its effect on viability and proliferation of rat bone marrow mesenchymal stem cells (BM-MSCs).

Materials and Methods

This experimental study evaluated the viability and morphology of MSCs in the presence of SNP (100 to 2000 µM) at 1, 5, and 15 hours. We chose the 100, 1000, and 2000 µM concentrations of SNP for one hour exposure for further analyses. Cell proliferation was investigated by the colony forming assay and population doubling number (PDN). Na⁺, K⁺, and Ca²⁺ levels as well as activities of lactate dehydrogenase (LDH), alkaline phosphatase (ALP), aspartate transaminase (AST), and alanine transaminase (ALT) were measured.

Results

The viability of MSCs dose-dependently reduced from 750 µM at one hour and 250 µM at 5 and 15 hours. The 100 µM caused no change in viability, however we observed a reduction in the cytoplasmic area at 5 and 15 hours. This change was not observed at one hour. The one hour treatment with 100 µM of SNP reduced the mean colony numbers but not the diameter when the cells were incubated for 7 and 14 days. In addition, one hour treatment with 100 µM of SNP significantly reduced ALT, AST, and ALP activities whereas the activity of LDH increased when incubated for 24 hours. The same treatment caused an increase in Ca²⁺ and reduction in Na⁺ content. The 1000 and 2000 µM concentrations reduced all the factors except Ca²⁺ and LDH which increased.

Conclusion

The high dose of SNP, even for a short time, was toxic. The low dose was safe with respect to viability and proliferation, especially over a short time. However elevated LDH activity might increase anaerobic metabolism.

Molecular signature of anastasis for reversal of apoptosis

Anastasis (Greek for "rising to life") is a cell recovery phenomenon that rescues dying cells from the brink of cell death. We recently discovered anastasis to occur after the execution-stage of apoptosis in vitro and in vivo. Promoting anastasis could in principle preserve injured cells that are difficult to replace, such as cardiomyocytes and neurons. Conversely, arresting anastasis in dying cancer cells after cancer therapies could improve treatment efficacy. To develop new therapies that promote or inhibit anastasis, it is essential to identify the key regulators and mediators of anastasis - the therapeutic targets. Therefore, we performed time-course microarray analysis to explore the molecular mechanisms of anastasis during reversal of ethanol-induced apoptosis in mouse primary liver cells. We found striking changes in transcription of genes involved in multiple pathways, including early activation of pro-cell survival, anti-oxidation, cell cycle arrest, histone modification, DNA-damage and stress-inducible responses, and at delayed times, angiogenesis and cell migration. Validation with RT-PCR confirmed similar changes in the human liver cancer cell line, HepG2, during anastasis. Here, we present the time-course whole-genome gene expression dataset revealing gene expression profiles during the reversal of apoptosis. This dataset provides important insights into the physiological, pathological, and therapeutic implications of anastasis.

Molecular signature of anastasis for reversal of apoptosis

Anastasis (Greek for "rising to life") is a cell recovery phenomenon that rescues dying cells from the brink of cell death. We recently discovered anastasis to occur after the execution-stage of apoptosis in vitro and in vivo. Promoting anastasis could in principle preserve injured cells that are difficult to replace, such as cardiomyocytes and neurons. Conversely, arresting anastasis in dying cancer cells after cancer therapies could improve treatment efficacy. To develop new therapies that promote or inhibit anastasis, it is essential to identify the key regulators and mediators of anastasis – the therapeutic targets. Therefore, we performed time-course microarray analysis to explore the molecular mechanisms of anastasis during reversal of ethanol-induced apoptosis in mouse primary liver cells. We found striking changes in transcription of genes involved in multiple pathways, including early activation of pro-cell survival, anti-oxidation, cell cycle arrest, histone modification, DNA-damage and stress-inducible responses, and at delayed times, angiogenesis and cell migration. Validation with RT-PCR confirmed similar changes in the human liver cancer cell line, HepG2, during anastasis. Here, we present the time-course whole-genome gene expression dataset revealing gene expression profiles during the reversal of apoptosis. This dataset provides important insights into the physiological, pathological, and therapeutic implications of anastasis.

Differential Regulation of Bcl-xL Gene Expression by Corticosterone, Progesterone, and Retinoic Acid

Corticosterone (CT), progesterone (PG), and retinoic acid (RA) are capable of inhibiting Doxorubicin (Dox) from inducing apoptosis in rat cardiomyocytes. Mechanistically, CT, PG, and RA induce increases of Bcl-xL protein and mRNA, and activate a 3.2 kb bcl-x gene promoter. CT and RA, but not PG, induced the activity of a 0.9 kb bcl-x promoter, containing sequences for AP-1 and NF-kB binding. RA, but not CT or PG, induced NF-kB activation. CT, but not PG or RA, induced AP-1 activation, and induction of the 0.9 kb bcl-x reporter by CT was inhibited by dominant negative c-Jun TAM-67 or removal of AP-1 binding site. Therefore, although CT, PG, and RA all induce Bcl-xL mRNA and protein, three independent mechanisms are in operation: while CT induces Bcl-xL via AP-1 transcription factor, and RA induces NF-kB activation and bcl-x promoter activity, PG induces Bcl-xL via a mechanism independent of NF-kB or AP-1.

Lesion-induced accumulation of platelets promotes survival of adult neural stem / progenitor cells

The presence of neural stem/progenitor cells (NSPCs) in specific areas of the central nervous system (CNS) supports tissue maintenance as well as regeneration. The subependymal zone (SEZ), located at the lateral ventricle's wall, represents a niche for NSPCs and in response to stroke or demyelination becomes activated with progenitors migrating towards the lesion and differentiating into neurons and glia. The mechanisms that underlie this phenomenon remain largely unknown. The vascular niche and in particular blood-derived elements such as platelets, has been shown to contribute to CNS regeneration in different pathological conditions. Indeed, intracerebroventricularly administrated platelet lysate (PL) stimulates angiogenesis, neurogenesis and neuroprotection in the damaged CNS. Here, we explored the presence of platelets in the activated SEZ after a focal demyelinating lesion in the corpus callosum of mice and we studied the effects of PL on proliferating SEZ-derived NSPCs in vitro. We showed that the lesion-induced increase in the size of the SEZ and in the number of proliferating SEZ-resident NSPCs correlates with the accumulation of platelets specifically along the activated SEZ vasculature. Expanding on this finding, we demonstrated that exposure of NSPCs to PL in vitro led to increased numbers of cells by enhanced cell survival and reduced apoptosis without differences in proliferation and in the differentiation potential of NSPCs. Finally, we demonstrate that the accumulation of platelets within the SEZ is spatially correlated with reduced numbers of apoptotic cells when compared to other periventricular areas. In conclusion, our results show that platelet-derived compounds specifically promote SEZ-derived NSPC survival and suggest that platelets might contribute to the enlargement of the pool of SEZ NSPCs that are available for CNS repair in response to injury.

A novel mechanism by which tissue transglutaminase activates signaling events that promote cell survival

Tissue transglutaminase (tTG) functions as a GTPase and an acyl transferase that catalyzes the formation of protein cross-links. tTG expression is frequently up-regulated in human cancer, where it has been implicated in various aspects of cancer progression, including cell survival and chemo-resistance. However, the extent to which tTG cooperates with other proteins within the context of a cancer cell, versus its intrinsic ability to confer transformed characteristics to cells, is poorly understood. To address this question, we asked what effect the ectopic expression of tTG in a non-transformed cellular background would have on the behavior of the cells. Using NIH3T3 fibroblasts stably expressing a Myc-tagged form of tTG, we found that tTG strongly protected these cells from serum starvation-induced apoptosis and triggered the activation of the PI3-kinase/mTOR Complex 1 (mTORC1)/p70 S6-kinase pathway. We determined that tTG forms a complex with the non-receptor tyrosine kinase c-Src and PI3-kinase, and that treating cells with inhibitors to block tTG function (monodansylcadaverine; MDC) or c-Src kinase activity (PP2) disrupted the formation of this complex, and prevented tTG from activating the PI3-kinase pathway. Moreover, treatment of fibroblasts over-expressing tTG with PP2, or with inhibitors that inactivate components of the PI3-kinase pathway, including PI3-kinase (LY294002) and mTORC1 (rapamycin), ablated the tTG-promoted survival of the cells. These findings demonstrate that tTG has an intrinsic capability to stimulate cell survival through a novel mechanism that activates PI3-kinase signaling events, thus highlighting tTG as a potential target for the treatment of human cancer.

In Vitro Anti-rotaviral Activity of Achillea kellalensis

Background

Achillea kellalensis, which is frequently used by Chaharmahal va Bakhtiarians residing in, Southwest of Iran, as a traditional herbal medicine for the treatment of acute diarrhea, has been selected to examine its antiviral activities against bovine rotavirus and cell toxicity activity in MA-104 cells.

Objectives

The aim of this study was to evaluate the in vitro cytotoxic and anti-rotavirus properties of crude extracts of A. kellalensis.

Materials and Methods

The dried and powdered flowers of Achillea kellalensis were extracted with hot water and ethanol 50% (v/v). The cell viability and toxicity of the extracts were evaluated on MA-104 cells using four methods; trypan blue dye, NR, crystal violet and MTT assay. The in vitro anti-rotavirus properties were determined via four different assays, in order to evaluate the direct inhibition and/or the inhibition of viral replication.

Results

Cytotoxicity of two A. kellalensis extracts showed different concentrations. Hydro-alcoholic extract had low CC₅₀ at 600 µg/mL by the NR assay while the aqueous extract had high CC₅₀ at 1000µg/mL by the crystal violet method. In the simultaneous treatment assay and post treatment assay, the extracts were able to prevent viral replication and inhibit the viral CPE on MA-104 cells at 10 TCID₅₀, but the extracts did not exhibit direct antiviral activity on rotavirus adsorption. The effective concentration (EC₅₀) of both extracts was observed to be 100 µg/mL.

Conclusions

These results indicate that A. kellalensis extracts exert potent anti-rotaviral activity only after viral adsorption. The two extracts from A. kellalensis showed a good selectivity index. Also these results suggest that extracts prepared from the flowers of A. kellalensis may be potential anti-rotaviral agents in vivo and be useful in veterinary medicine.

Pituitary adenylate cyclase-activating polypeptide (PACAP) promotes both survival and neuritogenesis in PC12 cells through activation of nuclear factor κB (NF-κB) pathway: involvement of extracellular signal-regulated kinase (ERK), calcium, and c-REL

The pituitary adenylate cyclase-activating polypeptide (PACAP) is a trophic factor that promotes neuronal survival and neurite outgrowth. However, the signaling pathways and the transcriptional mechanisms involved are not completely elucidated. Our previous studies aimed at characterizing the transcriptome of PACAP-differentiated PC12 cells revealed an increase in the expression of nuclear factor κB2 (NF-κB2) gene coding for p100/p52 subunit of NF-κB transcription factor. Here, we examined the role of the NF-κB pathway in neuronal differentiation promoted by PACAP. We first showed that PACAP-driven survival and neuritic extension in PC12 cells are inhibited following NF-κB pathway blockade. PACAP stimulated both c-Rel and p52 NF-κB subunit gene expression and nuclear translocation, whereas c-Rel down-regulation inhibited cell survival and neuritogenesis elicited by the neuropeptide. PACAP-induced c-Rel nuclear translocation was inhibited by ERK1/2 and Ca(2+) blockers. Furthermore, the neuropeptide stimulated NF-κB p100 subunit processing into p52, indicative of activation of the NF-κB alternative pathway. Taken together, our data show that PACAP promotes both survival and neuritogenesis in PC12 cells by activating NF-κB pathway, most likely via classical and alternative signaling cascades involving ERK1/2 kinases, Ca(2+), and c-Rel/p52 dimers.

Overexpression of human arginine decarboxylase rescues human mesenchymal stem cells against H₂O₂ toxicity through cell survival protein activation

In this study, we explored the potentiality of human arginine decarboxylase (ADC) to enhance the survival of mesenchymal stem cells (MSCs) against unfavorable milieu of host tissues as the low survival of MSCs is the issue in cell transplantation therapy. To address this, human MSCs overexpressing human ADC were treated with H2O2 and the resultant intracellular events were examined. First, we examined whether human ADC is overexpressed in human MSCs. Then, we investigated cell survival or death related events. We found that the overexpression of human ADC increases formazan production and reduces caspase 3 activation and the numbers of FITC, hoechst, or propidium iodide positive cells in human MSCs exposed to H2O2. To elucidate the factors underlying these phenomena, AKT, CREB, and BDNF were examined. We found that the overexpression of human ADC phosphorylates AKT and CREB and increases BDNF level in human MSCs exposed to H2O2. The changes of these proteins are possibly relevant to the elevation of agmatine. Collectively, our data demonstrate that the overexpression of human ADC stimulates pro-survival factors to protect human MSCs against H2O2 toxicity. In conclusion, the present findings support that ADC can enhance the survival of MSCs against hostile environment of host tissues.

Estrogen promotes breast cancer cell survival in an inhibitor of apoptosis (IAP)-dependent manner

The estrogen receptor (ER) is a major prognostic and therapeutic marker that is expressed in nearly 75% of breast tumors. We have previously shown that the presence of inflammatory mediators can alter the genomic function of the estrogen receptor (ER) in a gene specific manner. In particular, 17β-estradiol (E2) works in combination with the pro-inflammatory cytokines to enhance the expression of a number of pro-survival factors, including the Inhibitor of Apoptosis (IAP) family member, cIAP2. Here we confirm that mRNA and protein levels for cIAP2, but not the related family members cIAP1 and XIAP, are highly up-regulated in MCF-7 breast cancer cells by E2 and cytokines. Similar regulation of cIAP2 is evident in other ER positive but not ER negative cell lines. In agreement with its role as a pro-survival factor, cIAP2 is highly expressed in a subset of invasive breast carcinomas but not in normal breast tissue or ductal carcinoma in situ. Antagonizing IAPs with mimetics of SMAC, which is a known endogenous IAP antagonist, or knockdown of IAPs by siRNA led to greater cell death by TNFα and prevented E2 from promoting cell survival. In addition, a SMAC mimetic reversed TNFα resistance in ER positive breast cancer cells that express high levels of endogenous IAPs. In summary, our findings indicate a new mechanism by which E2 allows breast cancer cells to evade cell death and suggest that an antagonist of IAPs may be a potential therapeutic option for a subset of ER positive breast tumors.

Bioelectrical impedance may predict cell viability during ischemia and reperfusion in rat liver

Ischemia and reperfusion (I/R) injury is a major cause of hepatic failure after liver surgery, but no method could monitor or predict it real-time during surgery. We measured bioelectrical impedance (BEI) and cell viability to assess the usefulness of BEI during I/R in rat liver. A 70% partial liver ischemia model was used. BEI was measured at various frequencies. Adenosine triphosphate (ATP) content, and palmitic acid oxidation rate were measured, and histological changes were observed in order to quantify liver cell viability. BEI changed significantly during ischemia at low frequency. In the ischemia group, BEI increased gradually during 60 min of ischemia and had a tendency to plateau thereafter. The ATP content decreased below 20% of the baseline level. In the I/R group, BEI recovered to near baseline level. After 24 hr of reperfusion, the ATP contents decreased to below 50% in 30, 60 and 120 min of ischemia and the palmitic acid metabolic rates decreased to 91%, 78%, and 74%, respectively, compared with normal liver. BEI may be a good tool for monitoring I/R during liver surgery. The liver is relatively tolerant to ischemia, however after reperfusion, liver cells may be damaged depending upon the duration of ischemia.