Apoptosis and necrosis: detection, discrimination and phagocytosis

Morphological and Immunocytochemical Characterization of Paclitaxel-Induced Microcells in Sk-Mel-28 Melanoma Cells

Biomarkers, including proteins, nucleic acids, antibodies, and peptides, are essential for identifying diseases such as cancer and differentiating between healthy and abnormal cells in patients. To date, studies have shown that cancer stem cells have DNA repair mechanisms that deter the effects of medicinal treatment. Experiments with cell cultures and chemotherapy treatments of these cultures have revealed the presence of small cells, with a small amount of cytoplasm that can be intensively stained with azure eosin, called microcells. Microcells develop during sporosis from a damaged tumor macrocell. After anticancer therapy in tumor cells, a defective macrocell may produce one or more microcells. This study aims to characterize microcell morphology in melanoma cell lines. In this investigation, we characterized the population of cancer cell microcells after applying paclitaxel treatment to a Sk-Mel-28 melanoma cell line using immunocytochemical cell marker detection and fluorescent microscopy. Paclitaxel-treated cancer cells show stronger expression of stem-associated ALDH2, SOX2, and Nanog markers than untreated cells. The proliferation of nuclear antigens in cells and the synthesis of RNA in microcells indicate cell self-defense, promoting resistance to applied therapy. These findings improve our understanding of microcell behavior in melanoma, potentially informing future strategies to counteract drug resistance in cancer treatment.

A novel treatment approach using vitamin B12-conjugated sericin for mitigating nanodiamond-induced toxicity in darkling beetles

The escalating use of nanodiamonds (NDs) has raised concerns about their ecotoxicological impact, prompting exploration of therapeutic interventions. This paper pioneers the examination of Vitamin B12-conjugated sericin (VB12-SER) as a potential therapeutic approach against ND-induced toxicity in darkling beetles (Blaps polychresta). The study analyzes mortality rates and organ-specific effects, covering the testis, ovary, and midgut, before and after treatments. Following exposure to 10 mg NDs/g body weight, within a subgroup of individuals termed ND2 with a mortality rate below 50%, two therapeutic treatments were administered, including pure sericin (SER) at 10 mg/mL and VB12-SER at 10.12 mg/mL. Consequently, five experimental groups (control, SER, ND2, ND2+SER, ND2+SER+VB12) were considered. Kaplan-Meier survival analysis was performed to assess the lifespan distribution of the insects in these groups over a 30-d period. Analyses revealed increased mortality and significant abnormalities induced by NDs within the examined organs, including cell death, DNA damage, enzyme dysregulation, antioxidant imbalances, protein depletion, lipid peroxidation, and morphological deformities. In contrast, the proposed treatments, especially (ND2+SER+VB12), demonstrated remarkable recovery, highlighting VB12-conjugated SER's potential in mitigating ND-triggered adverse effects. Molecular docking simulations affirmed binding stability and favorable interactions of the VB12-SER complex with target proteins. This research enhances understanding of NDs' effects on B. polychresta, proposing it as an effective bioindicator, and introduces VB12-conjugated SER as a promising therapeutic strategy in nanotoxicological studies.

Programmed cell death, from liver Ischemia-Reperfusion injury perspective: An overview

Liver ischemia-reperfusion injury (LIRI) commonly occurs in liver resection, liver transplantation, shock, and other hemorrhagic conditions, resulting in profound local and systemic effects via associated inflammatory responses and hepatic cell death. Hepatocyte death is a significant component of LIRI and its mechanism was previously thought to be limited to apoptosis and necrosis. With the discovery of novel types of programmed cell death (PCD), necroptosis, ferroptosis, pyroptosis, autophagy, NETosis, and parthanatos have been shown to be involved in LIRI. Understanding the mechanisms underlying cell death following LIRI is indispensable to mitigating the widespread effects of LIRI. Here, we review the roles of different PCD and discuss potential therapy in LIRI.

Making the Brightest Ones Dim: Maximizing the Photothermal Conversion Efficiency of BODIPY-Based Photothermal Agents

The successful implementation of photothermal therapy (PTT) in cancer treatment hinges on the development of highly effective photothermal agents (PTAs). Boron dipyrromethene (BODIPY) dyes, being well known for their high brightness and quantum efficiencies, are the antithesis of PTAs. Nonetheless, a systematic exploration of the photophysics and photothermal characteristics of a series of π-extended BODIPY dyes with high absorptivity in the near-infrared (NIR) region has achieved superior photothermal conversion efficiencies (>90%), in both monomeric state and nanoparticles after encapsulation in a biocompatible polyethyleneglycol 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy-(polyethylene glycol)-2000]. Optimal PTA candidates combine strong NIR absorption provided by extended donor-acceptor conjugation and an optimization of the electronic and steric effects of meso-substituents to maximize photothermal conversion performance. The PTT-optimized meso-CF3-BODIPY, TCF3PEn exhibits exceptional efficacy in inducing cancer cell apoptosis and in vivo tumor ablation using low-power NIR laser irradiation (0.3 W cm-2, 808 nm) as well as excellent biological safety, underscoring its potential for advancing light-induced cancer therapies.

Phenazine Cations as Anticancer Theranostics†

The biological properties of two water-soluble organic cations based on polypyridyl structures commonly used as ligands for photoactive transition metal complexes designed to interact with biomolecules are investigated. A cytotoxicity screen employing a small panel of cell lines reveals that both cations show cytotoxicity toward cancer cells but show reduced cytotoxicity to noncancerous HEK293 cells with the more extended system being notably more active. Although it is not a singlet oxygen sensitizer, the more active cation also displayed enhanced potency on irradiation with visible light, making it active at nanomolar concentrations. Using the intrinsic luminescence of the cations, their cellular uptake was investigated in more detail, revealing that the active compound is more readily internalized than its less lipophilic analogue. Colocalization studies with established cell probes reveal that the active cation predominantly localizes within lysosomes and that irradiation leads to the disruption of mitochondrial structure and function. Stimulated emission depletion (STED) nanoscopy and transmission electron microscopy (TEM) imaging reveal that treatment results in distinct lysosomal swelling and extensive cellular vacuolization. Further imaging-based studies confirm that treatment with the active cation induces lysosomal membrane permeabilization, which triggers lysosome-dependent cell-death due to both necrosis and caspase-dependent apoptosis. A preliminary toxicity screen in the Galleria melonella animal model was carried out on both cations and revealed no detectable toxicity up to concentrations of 80 mg/kg. Taken together, these studies indicate that this class of synthetically easy-to-access photoactive compounds offers potential as novel therapeutic leads.

Enhancing Phototoxicity in Human Colorectal Tumor Cells Through Nanoarchitectonics for Synergistic Photothermal and Photodynamic Therapies

Phototherapies are promising for noninvasive treatment of aggressive tumors, especially when combining heat induction and oxidative processes. Herein, we show enhanced phototoxicity of gold shell-isolated nanorods conjugated with toluidine blue-O (AuSHINRs@TBO) against human colorectal tumor cells (Caco-2) with synergic effects of photothermal (PTT) and photodynamic therapies (PDT). Mitochondrial metabolic activity tests (MTT) performed on Caco-2 cell cultures indicated a photothermal effect from AuSHINRs owing to enhanced light absorption from the localized surface plasmon resonance (LSPR). The phototoxicity against Caco-2 cells was further increased with AuSHINRs@TBO where oxidative processes, such as hydroperoxidation, were also present, leading to a cell viability reduction from 85.5 to 39.0%. The molecular-level mechanisms responsible for these effects were investigated on bioinspired tumor membranes using Langmuir monolayers of Caco-2 lipid extract. Polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS) revealed that the AuSHINRs@TBO incorporation is due to attractive electrostatic interactions with negatively charged groups of the Caco-2 lipid extract, resulting in the expansion of surface pressure isotherms. Upon irradiation, Caco-2 lipid extract monolayers containing AuSHINRs@TBO (1:1 v/v) exhibited ca. 1.0% increase in surface area. This is attributed to the generation of reactive oxygen species (ROS) and their interaction with Caco-2 lipid extract monolayers, leading to hydroperoxide formation. The oxidative effects are facilitated by AuSHINRs@TBO penetration into the polar groups of the extract, allowing oxidative reactions with carbon chain unsaturations. These mechanisms are consistent with findings from confocal fluorescence microscopy, where the Caco-2 plasma membrane was the primary site of the cell death induction process.

Drug-Loaded Polydopamine Nanoparticles for Chemo/Photothermal Therapy against Colorectal Cancer Cells

Colorectal cancer (CRC) is a common and deadly malignancy, ranking second in terms of mortality and third in terms of incidence on a global scale. The survival rates for CRC patients are unsatisfactory primarily because of the absence of highly effective clinical strategies. The efficacy of existing CRC treatments, such as chemotherapy (CT), is constrained by issues such as drug resistance and damage to healthy tissues. Alternative approaches such as photothermal therapy (PTT), while offering advantages over traditional therapies, suffer instead from a low efficiency in killing tumor cells when used alone. In this context, nanostructures can efficiently contribute to a selective and targeted treatment. Here, we combined CT and PTT by developing a nanoplatform based on polydopamine nanoparticles (PDNPs), selected for their biocompatibility, drug-carrying capabilities, and ability to produce heat upon exposure to near-infrared (NIR) irradiation. As a chemotherapy drug, sorafenib has been selected, a multikinase inhibitor already approved for clinical use. By encapsulating sorafenib in polydopamine nanoparticles (Sor-PDNPs), we were able to successfully improve the drug stability in physiological media and the consequent uptake by CRC cells, thereby increasing its therapeutic effects. Upon NIR stimulus, Sor-PDNPs can induce a temperature increment of about 10 °C, encompassing both PTT and triggering a localized and massive drug release. Sor-PDNPs were tested on healthy colon cells, showing minimal adverse outcomes; conversely, they demonstrated excellent efficacy against CRC cells, with a strong capability to hinder cancer cell proliferation and induce apoptosis. Obtained findings pave the way to new synergistic chemo-photothermal approaches, maximizing the therapeutic outcomes against CRC while minimizing side effects on healthy cells.

Ethanolic extract from leaves of tithonia diversifolia induces apoptosis in HCT-116 cells through oxidative stress

Tithonia diversifolia is a perennial bushy plant found in South America with significant ethnopharmacological importance as an antimalarial, antidiabetic, antibacterial, and anticancer agent. The aim of the present study was to determine the cytotoxicity of the ethanolic extract from leaves of T. diversifolia (TdE) on human cancer cell lines (HCT-116, SNB-19, NCIH-460 and MCF-7), as well as the mechanism of action involved in cell death and cellular modulation of oxidative stress. The TdE exhibited significant activity with IC50 values ranging from 7.12 to 38.41 μg/ml, with HCT-116 being the most sensitive cell line. Subsequent experiments were conducted with HCT-116 cell line. TdE decreased the number of viable cells, followed by induction of apoptotic events, increase in mitochondrial membrane permeabilization, and enhanced G2/M phase of the cell cycle. Pro-oxidative effects including elevated acidic vesicular organelle formation, lipid peroxidation, and nitric oxide by-products, as well as reduced levels of intracellular glutathione and reactive oxygen species production were also observed following incubation with TdE, which may lead to DNA damage followed by apoptotic cell death. These results demonstrate the potential of TdE ethanolic leaf extraction for biological activity and enhance the importance of continuing to study natural sources of plants for the development of anticancer agents.

Cellular and molecular mechanisms of cell damage and cell death in ischemia-reperfusion injury in organ transplantation

Ischemia-reperfusion injury (IRI) is a critical pathological condition in which cell death plays a major contributory role, and negatively impacts post-transplant outcomes. At the cellular level, hypoxia due to ischemia disturbs cellular metabolism and decreases cellular bioenergetics through dysfunction of mitochondrial electron transport chain, causing a switch from cellular respiration to anaerobic metabolism, and subsequent cascades of events that lead to increased intracellular concentrations of Na+, H+ and Ca2+ and consequently cellular edema. Restoration of blood supply after ischemia provides oxygen to the ischemic tissue in excess of its requirement, resulting in over-production of reactive oxygen species (ROS), which overwhelms the cells' antioxidant defence system, and thereby causing oxidative damage in addition to activating pro-inflammatory pathways to cause cell death. Moderate ischemia and reperfusion may result in cell dysfunction, which may not lead to cell death due to activation of recovery systems to control ROS production and to ensure cell survival. However, prolonged and severe ischemia and reperfusion induce cell death by apoptosis, mitoptosis, necrosis, necroptosis, autophagy, mitophagy, mitochondrial permeability transition (MPT)-driven necrosis, ferroptosis, pyroptosis, cuproptosis and parthanoptosis. This review discusses cellular and molecular mechanisms of these various forms of cell death in the context of organ transplantation, and their inhibition, which holds clinical promise in the quest to prevent IRI and improve allograft quality and function for a long-term success of organ transplantation.

Comprehensive toxicity assessment of nanodiamond on Blaps polychresta: implications and novel findings

With the increasing development of nanomaterials, the use of nanodiamonds (NDs) has been broadly manifested in many applications. However, their high penetration into the ecosystem indubitably poses remarkable toxicological risks. This paper investigates the toxic effects of NDs on the darkling beetle, Blaps polychresta Forskal, 1775 (Coleoptera: Tenebrionidae). Survival analysis was carried out by monitoring the beetles for 30 d after the injection of four different doses of NDs. A dose of 10.0 mg NDs/g body weight, causing less than 50% mortality effect, was assigned in the analysis of the different organs of studied beetles, including testis, ovary, and midgut. Structural and ultrastructural analyses were followed using light, TEM, and SEM microscopes. In addition, a variety of stress markers and enzyme activities were assessed using spectrophotometric methods. Furthermore, cell viability and DNA damage were evaluated using cytometry and comet assay, respectively. Compared to the control group, the NDs-treated group was exposed to various abnormalities within all the studied organs as follows. Significant disturbances in enzyme activities were accompanied by an apparent dysregulation in the antioxidant system. The flow cytometry results indicated a substantial decrease of viable cells along with a rise of apoptotic and necrotic cells. The comet assay demonstrated a highly increased level of DNA damage. Likewise, histological analyses accentuated the same findings showing remarkable deformities in the studied organs. Prominently, the research findings substantially contribute for the first time to evaluating the critical effects of NDs on B. polychresta, adopted as the bioindicator in this paper.

Diffractaic acid exerts anti-cancer effects on hepatocellular carcinoma HepG2 cells by inducing apoptosis and suppressing migration through targeting thioredoxin reductase 1

Hepatocellular carcinoma (HCC) represents one of the most common malignant tumors worldwide. Due to the limited number of available drugs and their side effects, the development of new chemotherapeutic strategies for HCC treatment has become increasingly important. This study is aimed at investigating whether diffractaic acid (DA), one of the secondary metabolites of lichen, exhibits a potential anticancer effect on HepG2 cells and whether its anticancer effect is mediated by inhibition of thioredoxin reductase 1 (TRXR1), which is a target of chemotherapeutic strategies due to overexpression in tumor cells including HCC. XTT assay results showed that DA exhibited strong cytotoxicity on HepG2 cells with an IC50 value of 78.07 µg/mL at 48 h. Flow cytometric analysis results revealed that DA displayed late apoptotic and necrotic effects on HepG2 cells. Consistent with these findings, real-time PCR results showed that DA did not alter the BAX/BCL2 ratio in HepG2 cells but upregulated the P53 gene. Moreover, the wound healing assay results revealed a strong anti-migratory effect of DA in HepG2 cells. Real-time PCR and Western blot analyses demonstrated that DA increased TRXR1 gene and protein expression levels, whereas enzyme activity studies disclosed that DA inhibited TRXR1. These findings suggest that DA has an anticancer effect on HepG2 cells by targeting the enzymatic inhibition of TRXR1. In conclusion, DA as a TRXR1 inhibitor can be considered an effective chemotherapeutic agent which may be a useful lead compound for the treatment of HCC.

Hellebrigenin triggers death of promyelocytic leukemia cells by non-genotoxic ways

Bufadienolides are digitalis-like aglycones mainly found in skin secretions of toads. Among their biological properties, the mechanisms of antiproliferative action on tumor cells remain unclear for many compounds, including against leukemia cells. Herein, it was evaluated the mechanisms involved in the antiproliferative and genotoxic actions of hellebrigenin on tumor cell lines and in silico capacity to inhibit the human topoisomerase IIa enzyme. Firstly, its cytotoxic action was investigated by colorimetric assays in human tumor and peripheral blood mononuclear cells (PBMC). Next, biochemical and morphological studies were detailed by light microscopy (trypan blue dye exclusion), immunocytochemistry (BrdU uptake), flow cytometry and DNA/chromosomal damages (Cometa and aberrations). Finally, computational modelling was used to search for topoisomerase inhibition. Hellebrigenin reduced proliferation, BrdU incorporation, viability, and membrane integrity of HL-60 leukemia cells. Additionally, it increased G2/M arrest, internucleosomal DNA fragmentation, mitochondrial depolarization, and phosphatidylserine externalization in a concentration-dependent manner. In contrast to doxorubicin, hellebrigenin did not cause DNA strand breaks in HL-60 cell line and lymphocytes, and it interacts with ATPase domain residues of human topoisomerase IIa, generating a complex of hydrophobic and van der Waals interactions and hydrogen bonds. So, hellebrigenin presented potent anti-leukemic activity at concentrations as low as 0.06 μM, a value comparable to the clinical anticancer agent doxorubicin, and caused biochemical changes suggestive of apoptosis without genotoxic/clastogenic-related action, but it probably triggers catalytic inhibition of topoisomerase II. These findings also emphasize toad steroid toxins as promising lead antineoplasic compounds with relatively low cytotoxic action on human normal cells.

Sarin-Induced Neuroinflammation in Mouse Brain Is Attenuated by the Caspase Inhibitor Q-VD-OPh

Organophosphates cause hyperstimulation of the central nervous system, leading to extended seizures, convulsions, and brain damage. Sarin is a highly toxic organophosphate nerve agent that has been employed in several terrorist attacks. The prolonged toxicity of sarin may be enhanced by the neuroinflammatory response initiated by the inflammasome, caspase involvement, and generation/release of proinflammatory cytokines. Since neurodegeneration and neuroinflammation are prevalent in sarin-exposed animals, we were interested in evaluating the capacity of quinolyl-valyl-O-methylaspartyl-[-2,6-difluorophenoxy]-methyl ketone (Q-VD-OPh), a pan caspase inhibitor to attenuate neuroinflammation following sarin exposure. To test this hypothesis, sarin-exposed C57BL/6 mice were treated with Q-VD-OPh or negative control quinolyl-valyl-O-methylglutamyl-[-2,6-difluorophenoxy]-methyl ketone, sacrificed at 2- and 14-day time points, followed by removal of the amygdala and hippocampus. A Bio-Rad 23-Plex cytokine analysis was completed on each tissue. The results suggest that exposure to sarin induced a dramatic increase in interleukin-1β and 6 other cytokines and a decrease in 2 of the 23 cytokines at 2 days in the amygdala compared with controls. Q-VD-OPh attenuated these changes at the 2-day time point. At 14 days, six of these cytokines were still significantly different from controls. Hippocampus was less affected at both time points. Diazepam, a neuroprotective drug against nerve agents, caused an increase in several cytokines but did not have a synergistic effect with Q-VD-OPh. Treatment of sarin exposure with apoptosis inhibitors appears to be a worthwhile approach for further testing as a comprehensive counteragent against organophosphate exposure. SIGNIFICANCE STATEMENT: A pan inhibitor of caspases (Q-VD-OPh) was proposed as a potential antidote for sarin-induced neuroinflammation by reducing the level of inflammation via inflammasome caspase inhibition. Q-VD-OPh added at 30 minutes post-sarin exposure attenuated the inflammatory response of a number of cytokines and chemokines in the amygdala and hippocampus, two brain regions sensitive to organophosphate exposure. Apoptotic marker reduction at 2 and 14 days further supports further testing of inhibitors of apoptosis as a means to lessen extended organophosphate toxicity in the brain.

Calcium hypochlorite cytotoxicity mechanism in fibroblasts and effect on osteoblast mineralization

AIM

To determine the cytotoxicity mechanism of 2.5% calcium hypochlorite [Ca(OCl)2 ] in L929 fibroblasts and the effect of this solution on human osteoblast-like cells (Saos-2) mineralization, compared to that of 2.5% sodium hypochlorite (NaOCl).

METHODOLOGY

L929 fibroblasts were exposed to Ca(OCl)2 and NaOCl at different dilutions for 10 min. Cell metabolism was assessed by methyl-thiazole-tetrazolium (MTT); lysosome integrity, by neutral red (NR) assay; type of cell death, by flow cytometry (apoptosis/necrosis); cytoskeleton, by actin and α-tubulin fluorescence and cell ultrastructure, by transmission electron microscopy (TEM). The alkaline phosphatase (ALP) activity and mineralized nodule formation were determined in Saos-2 by thymolphthalein release and alizarin red staining (ARS), respectively. The data were analysed by two-way anova and Bonferroni's post-test (α = .05).

RESULTS

Ca(OCl)2 promoted higher cell viability and a lower percentage of apoptosis and necrosis than NaOCl (p < .05). Ca(OCl)2 and NaOCl decreased cell metabolism and lysosome integrity, induced the breakdown of microtubules and actin filaments, promoted alterations of rough endoplasmic reticulum and disruption of mitochondrial cristae. Additionally, Ca(OCl)2 did not induce ALP activity and had no effect on mineralized nodules formation.

CONCLUSIONS

Although Ca(OCl)2 and NaOCl promoted the same cytotoxicity mechanism, Ca(OCl)2 was less cytotoxic than NaOCl. As for ALP activity, no differences were observed between NaOCl and Ca(OCl)2 . The production of mineralized nodules induced by Ca(OCl)2 was lower than those induced by NaOCl, but was not different from those induced by the control group.

ATP-induced cell death: a novel hypothesis for osteoporosis

ATP-induced cell death has emerged as a captivating realm of inquiry with profound ramifications in the context of osteoporosis. This study unveils a paradigm-shifting hypothesis that illuminates the prospective involvement of ATP-induced cellular demise in the etiology of osteoporosis. Initially, we explicate the morphological attributes of ATP-induced cell death and delve into the intricacies of the molecular machinery and regulatory networks governing ATP homeostasis and ATP-induced cell death. Subsequently, our focus pivots towards the multifaceted interplay between ATP-induced cellular demise and pivotal cellular protagonists, such as bone marrow-derived mesenchymal stem cells, osteoblasts, and osteoclasts, accentuating their potential contributions to secondary osteoporosis phenotypes, encompassing diabetic osteoporosis, glucocorticoid-induced osteoporosis, and postmenopausal osteoporosis. Furthermore, we probe the captivating interplay between ATP-induced cellular demise and alternative modalities of cellular demise, encompassing apoptosis, autophagy, and necroptosis. Through an all-encompassing inquiry into the intricate nexus connecting ATP-induced cellular demise and osteoporosis, our primary goal is to deepen our comprehension of the underlying mechanisms propelling this malady and establish a theoretical bedrock to underpin the development of pioneering therapeutic strategies.

Flanking N- and C-terminal domains of PrsA in Streptococcus suis type 2 are crucial for inducing cell death independent of TLR2 recognition

Streptococcus suis type 2 (SS2), a major emerging/re-emerging zoonotic pathogen found in humans and pigs, can cause severe clinical infections, and pose public health issues. Our previous studies recognized peptidyl-prolyl isomerase (PrsA) as a critical virulence factor promoting SS2 pathogenicity. PrsA contributed to cell death and operated as a pro-inflammatory effector. However, the molecular pathways through which PrsA contributes to cell death are poorly understood. Here in this study, we prepared the recombinant PrsA protein and found that pyroptosis and necroptosis were involved in cell death stimulated by PrsA. Specific pyroptosis and necroptosis signalling inhibitors could significantly alleviate the fatal effect. Cleaved caspase-1 and IL-1β in pyroptosis with phosphorylated MLKL proteins in necroptosis pathways, respectively, were activated after PrsA stimulation. Truncated protein fragments of enzymatic PPIase domain (PPI), N-terminal (NP), and C-terminal (PC) domains fused with PPIase, were expressed and purified. PrsA flanking N- or C-terminal but not enzymatic PPIase domain was found to be critical for PrsA function in inducing cell death and inflammation. Additionally, PrsA protein could be anchored on the cell surface to interact with host cells. However, Toll-like receptor 2 (TLR2) was not implicated in cell death and recognition of PrsA. PAMPs of PrsA could not promote TLR2 activation, and no rescued phenotypes of death were shown in cells blocking of TLR2 receptor or signal-transducing adaptor of MyD88. Overall, these data, for the first time, advanced our perspective on PrsA function and elucidated that PrsA-induced cell death requires its flanking N- or C-terminal domain but is dispensable for recognizing TLR2. Further efforts are still needed to explore the precise molecular mechanisms of PrsA-inducing cell death and, therefore, contribution to SS2 pathogenicity.

Gold standard assessment of immunogenic cell death induced by photodynamic therapy: From in vitro to tumor mouse models and anti-cancer vaccination strategies

The discovery of the concept of immunogenic cell death (ICD) is a cornerstone in the development of novel anti-cancer immunotherapeutic approaches. Induction of the ICD pathway by specific anti-cancer therapeutic regimens can eliminate cancer cells by directly killing them during therapy and by activation of strong and specific anti-cancer immunity, leading to a long-lasting immunological memory that prevents cancer recurrence. ICD encompasses different forms of regulated cell death and can be triggered by many anti-cancer treatment modalities, including photodynamic therapy (PDT). PDT is a multistep procedure involving the accumulation of a light-sensitive dye known as a photosensitizer (PS) in tumor cells, followed by its activation by irradiation with a light of an appropriate wavelength. In the presence of molecular oxygen, the irradiated PS leads to the generation of cytotoxic reactive oxygen species, which can lead to ICD induction in the cancer cells. Here, we first describe in vitro methods to help optimize the PDT procedure for a specific PS. We also provide a collection of protocols and techniques for assessing ICD in vitro, including analysis of the emission of damage associated molecular patterns (DAMPs), efferocytosis, and the maturation and activation state of antigen presenting cells. Next, we describe in detail protocols for diverse tumor mouse models for assessing and characterizing ICD in vivo, such as murine tumor vaccination models. Finally, as an immunotherapeutic vaccine, we suggest using either PDT-induced dead cancer cells, preferably undergoing ICD, or dendritic cells loaded with lysates of PDT-induced cancer cells in a syngeneic orthotopic glioma model. Overall, this methodological article provides a quantitative, comprehensive set of validated tools that can be successfully used, with some adaptations, to identify, optimize and validate novel PSs in vitro and in vivo for the efficient induction of ICD during photodynamic treatment.

Improved Cytotoxicity and Induced Apoptosis in HeLa Cells by Co-loading Vitamin E Succinate and Curcumin in Nano-MIL-88B-NH2

One of the strategies for improved therapeutic effects in cancer therapy is combination chemotherapy. In this study, a flexible nano-MOF (Fe-MIL-88B-NH2 ) was synthesized in a sonochemical process, then co-loaded with α-tocopheryl succinate (TOS) and curcumin (CCM). The anticancer activity of co-loaded Fe-MIL-88B-NH2 (Fe-MIL-88B-NH2 /TOS@CCM) against the HeLa cells was compared with that of the single-loaded counterpart (Fe-MIL-88B-NH2 @CCM). MTT analysis indicates improved cytotoxicity of Fe-MIL-88B-NH2 /TOS@CCM. The data from the cell apoptosis assay indicated more apoptosis in the case of the co-loaded nano-MOF. This study indicates the positive effect of the presence of TOS on enhancing the anticancer effect of Fe-MIL-88B-NH2 @CCM to prepare a more efficient drug delivery nanosystem.

Unveiling the mechanisms underlying photothermal efficiency of gold shell-isolated nanoparticles (AuSHINs) on ductal mammary carcinoma cells (BT-474)

Gold nanoparticles are valuable photothermal agents owing to their efficient photothermal conversion, photobleaching resistance, and potential surface functionalization. Herein, we combined bioinspired membranes with in vitro assays to elicit the molecular mechanisms of gold shell-isolated nanoparticles (AuSHINs) on ductal mammary carcinoma cells (BT-474). Langmuir and Langmuir-Schaefer (LS) films were handled to build biomembranes from BT-474 lipid extract. AuSHINs incorporation led to surface pressure-area (π-A) isotherms expansion, increasing membrane flexibility. Fourier-transform infrared spectroscopy (FTIR) of LS multilayers revealed electrostatic AuSHINs interaction with head portions of BT-474 lipid extract, causing lipid chain disorganization. Limited AuSHINs insertion into monolayer contributed to hydroperoxidation of the unsaturated lipids upon irradiation, consistently with the surface area increments of ca. 2.0%. In fact, membrane disruption of irradiated BT-474 cells containing AuSHINs was confirmed by confocal microscopy and LDH leakage, with greater damage at 2.2 × 1013 AuSHINs/mL. Furthermore, the decrease in nuclei dimensions indicates cell death through photoinduced damage.

Seeing beyond apoptosis: ultrastructural aspects of necrosis in human atherosclerosis

In recent years, there has been an explosive growth of research to decipher the pathobiologic relevance of cell death in the development and progression of various cardiovascular disorders such as arterial remodeling and atherosclerosis. High rates of cell death have been reported in animal models, particularly following balloon catheter injury. Also, in humans there is considerable evidence indicating a close connection between cell death and atherosclerosis. In this regard, diverse biochemical and molecular analysis have suggested that intraplaque cells preferentially die by apoptosis, a mode of cell death considered to be active, highly regulated and programmed. In contrast to apoptosis, necrosis has been classically defined as an uncontrolled form of cell death that can occur in response to chemical or physical insults such as trauma, infection, toxins, or lack of blood supply. Necrosis has long been known to be present within atherosclerotic plaques but to date it is still less well understood and characterized than apoptosis. In addition, although electron microscopy (EM) remains essential in cell death research, only a very small proportion of studies deal with the ultrastructural aspects of cell death and/or include EM images to support their findings. As a consequence, many features of cell death modes in human atherosclerosis have not yet been thoroughly investigated and defined. The present study was undertaken to provide an ultrastructural description of the route/s by which intraplaque cells can die also suggesting novel insights for future research.

A New Diterpenoid of Indonesian Scoparia dulcis Linn: Isolation and Cytotoxic Activity against MCF-7 and T47D Cell Lines

Scoparia dulcis Linn plays an important role in treatment because it contains active compounds that are proven to have a variety of activities, including cytotoxicity on various cancer cells. The objective of this study is to isolate and identify the cytotoxic compounds in the ethyl acetate fraction of Scoparia dulcis, observe cell cycle inhibition and induction of apoptosis in vitro, and carry out molecular studies using in silico studies. A new diterpene compound was isolated from the ethyl acetate fraction of Scoparia dulcis L. of Indonesian origin. Chromatographic methods were used to isolate the compound, spectroscopic methods were used to elucidate its structure, and these data were compared with those reported in the literature. The compound was tested for its cytotoxic activity against two breast cancer cells (MCF-7 and T47D). The results of the isolated compound showed a cytotoxic effect on MCF-7 and T47D breast cancer cells at IC50 70.56 ± 1.54 and <3.125 ± 0.43 µg/mL, respectively. The compound inhibited the growth of MCF-7 and T47D breast cancer cells and the accumulation of cells in the G1 phases, and it induced apoptosis. Based on a spectroscopic analysis, the isolated compound was identified as 2α-hydroxyscopadiol, which is a new diterpenoid. A docking study revealed that the isolate's hydroxyl groups are essential for interacting with crucial residues on the active sites of the ER and PR and caspase-9. The isolate inhibits ER and PR activity with binding energies of -8.2 kcal/mol and -7.3 kcal/mol, respectively. In addition, the isolate was also able to induce apoptosis through the activation of the caspase-9 pathway with an affinity of -9.0 kcal/mol. In conclusion, the isolated compound from S. dulcis demonstrated anticancer activity based on in vitro and in silico studies.

Cigarette Smoke-Induced Respiratory Response: Insights into Cellular Processes and Biomarkers

Cigarette smoke (CS) poses a significant risk factor for respiratory, vascular, and organ diseases owing to its high content of harmful chemicals and reactive oxygen species (ROS). These substances are known to induce oxidative stress, inflammation, apoptosis, and senescence due to their exposure to environmental pollutants and the presence of oxidative enzymes. The lung is particularly susceptible to oxidative stress. Persistent oxidative stress caused by chronic exposure to CS can lead to respiratory diseases such as chronic obstructive pulmonary disease (COPD), pulmonary fibrosis (PF), and lung cancer. Avoiding exposure to environmental pollutants, like cigarette smoke and air pollution, can help mitigate oxidative stress. A comprehensive understanding of oxidative stress and its impact on the lungs requires future research. This includes identifying strategies for preventing and treating lung diseases as well as investigating the underlying mechanisms behind oxidative stress. Thus, this review aims to investigate the cellular processes induced by CS, specifically inflammation, apoptosis, senescence, and their associated biomarkers. Furthermore, this review will delve into the alveolar response provoked by CS, emphasizing the roles of potential therapeutic target markers and strategies in inflammation and oxidative stress.

PRMT1 reverts the immune escape of necroptotic colon cancer through RIP3 methylation

Necroptosis plays a double-edged sword role in necroptotic cancer cell death and tumor immune escape. How cancer orchestrates necroptosis with immune escape and tumor progression remains largely unclear. We found that RIP3, the central activator of necroptosis, was methylated by PRMT1 methyltransferase at the amino acid of RIP3 R486 in human and the conserved amino acid R479 in mouse. The methylation of RIP3 by PRMT1 inhibited the interaction of RIP3 with RIP1 to suppress RIP1-RIP3 necrosome complex, thereby blocking RIP3 phosphorylation and necroptosis activation. Moreover, the methylation-deficiency RIP3 mutant promoted necroptosis, immune escape and colon cancer progression due to increasing tumor infiltrated myeloid-derived immune suppressor cells (MDSC), while PRMT1 reverted the immune escape of RIP3 necroptotic colon cancer. Importantly, we generated a RIP3 R486 di-methylation specific antibody (RIP3ADMA). Clinical patient samples analysis revealed that the protein levels of PRMT1 and RIP3ADMA were positively correlated in cancer tissues and both of them predicted the longer patient survival. Our study provides insights into the molecular mechanism of PRMT1-mediated RIP3 methylation in the regulation of necroptosis and colon cancer immunity, as well as reveals PRMT1 and RIP3ADMA as the valuable prognosis markers of colon cancer.

New insights into the oxidative damage and antioxidant defense mechanism in Manila clams (Ruditapes philippinarum) exposed to 8:2 polyfluoroalkyl phosphate diester stress

8:2 perfluoroalkyl phosphate diester (8:2 diPAP) is the main precursor of perfluoroalkyl carboxylic acids, and it has been detected in a wide range of environments. In this study, conventional biochemical and histopathological analyses and transcriptome methods were used to investigate the accumulation and oxidative stress of 8:2 diPAP in Manila clams (Ruditapes philippinarum) as well as the clam's defense mechanisms for the first time. The hepatopancreas was the main target organ for 8:2 diPAP accumulation; the concentration reached 484.0 ± 15.5 ng/g after 7 days of exposure to 10 μg/L of 8:2 diPAP, which was 2-100 times higher than that found in other organs. 8:2 diPAP accumulation resulted in significant lipid peroxidation, and the change in malondialdehyde content was highly correlated with 8:2 diPAP accumulation (r > 0.8). The antioxidant enzymes catalase and peroxidase were significantly activated at 7 days of exposure. Although the levels subsequently returned to normal, this restoration was unable to prevent damage. Histopathological analysis showed that 8:2 diPAP exposure resulted in inflammatory damage to the hepatopancreas, which failed to resolve during the recovery period. Transcriptomic analyses showed that the expression of differentially expressed genes had different degrees of positive/negative correlation with antioxidant indicators, and they were significantly enriched in cell death regulatory pathways such as autophagy, apoptosis, and necrosis. The core factor expression results indicated that 8:2 diPAP exposure induced activation of the organismal autophagy factor followed by a shift towards apoptosis. In addition, pathways related to amino acid metabolism and energy metabolism were involved in determining the cell fate of Manila clams. Overall, these results indicated that 8:2 diPAP induced peroxidation of membrane lipids, disturbed physiological processes, and ultimately initiated programmed cell death in Manila clams. The findings of this study provide new insights into the mechanism of toxicity of 8:2 diPAP exposure in marine bivalves.

Exploring the cell death mechanisms of cytotoxic [1,2,3]triazolylcarborane lead compounds against U87 MG human glioblastoma cells

Moving towards high-grade glioma drug discovery, this study aimed to detect the mechanism of cellular death (apoptosis, necrosis and/or autophagy) induced by three carboranyl-based lead compounds. For that, we performed in U87 MG cells, flow cytometry experiments, as the gold standard technique, as well as confocal microscopy and ¹ H-NMR experiments as non-invasive assays. We selected three hybrid leads (1-3) from the in-house-library and the corresponding parent compounds, and recognized tyrosine kinase inhibitors (lapatinib, sunitinib and erlotinib) to put to the test in these experiments. Flow cytometry with Annexin V-FITC/DAPI staining showed that leads 1 and 3 and lapatinib mainly induced necrosis in U87 MG upon a 24 h treatment at IC₅₀ dose; meanwhile, hybrid 2, sunitinib and erlotinib seem to induce apoptosis in such cells. In general, confocal microscopy studies were in agreement with flow cytometry observing loss of cell membrane integrity in necrotic cells and features of apoptosis, that is, chromatin condensation, in apoptotic cells. Finally, NMR results showed that glioblastoma cells treated with hybrid 1, 3 or lapatinib displayed changes in CH₂ /CH₃ signal ratio and choline signals that could indicate necrotic cell death mechanism: meanwhile, 2-, sunitinib- or erlotinib-treated cells showed apoptotic characteristic behaviors. Additionally, carboranyl-hybrid 2 also produced autophagy in U87 MG cells.

Ultrastructural changes in feline oocytes during ovary storage for 24- and 48-hours

Despite established microscopic markers of feline oocyte quality, little is known about their ultrastructural traits. To the best of our knowledge, there is no published report analysing the effect of 24 and 48 h ovarian storage time on the domestic cat oocytes characteristics at the ultrastructural level. Oocytes (n = 30) were classified using the light microscopy as good or bad quality and then proceeded for TEM observations. The location, shape, size and distribution of each organelle was noted in each examined oocyte. In in good quality oocytes the cytoplasmic organelles were generally easier to identify, and furthermore its distribution pattern was more obvious to spot than in bad quality ones. Whereas bad quality oocytes were typically characterised by the lower visibility of the cellular structures and cytoplasmic architecture was less apparent and often arranged without a predictable pattern. In good quality oocytes obtained from fresh ovaries cytoplasmic vacuoles (CVs) occupied a significantly larger area (0,72 vs. 0.18 CVs/μm², respectively) than in bad quality ones, whereas in bad quality and stored oocytes more cytoplasm was occupied by lipid droplets (LDs) than in fresh good oocytes (0,22 ± 0,09 vs. 0,09 ± 0,05 respectively). It can be concluded that ultrastructure changes in feline oocytes during 24 and 48 h ovarian storage cannot be assessed in light microscopy. The ultrastructure of oocytes was seriously disturbed after 48 h of ovary storage, despite being classified as good quality. However, further investigations utilizing more cells are necessary to confirm reported traits of ultrastructure changes in stored and non-stored oocytes of good and bad quality.

Anticancer properties of bromelain: State-of-the-art and recent trends

Bromelain is a key enzyme found in pineapple (Ananas comosus (L.) Merr.); a proteolytic substance with multiple beneficial effects for human health such as anti-inflammatory, immunomodulatory, antioxidant and anticarcinogenic, traditionally used in many countries for its potential therapeutic value. The aim of this updated and comprehensive review focuses on the potential anticancer benefits of bromelain, analyzing the cytotoxic, apoptotic, necrotic, autophagic, immunomodulating, and anti-inflammatory effects in cancer cells and animal models. Detailed information about Bromelain and its anticancer effects at the cellular, molecular and signaling levels were collected from online databases such as PubMed/MedLine, TRIP database, GeenMedical, Scopus, Web of Science and Google Scholar. The results of the analyzed studies showed that Bromelain possesses corroborated pharmacological activities, such as anticancer, anti-edema, anti-inflammatory, anti-microbial, anti-coagulant, anti-osteoarthritis, anti-trauma pain, anti-diarrhea, wound repair. Nonetheless, bromelain clinical studies are scarce and still more research is needed to validate the scientific value of this enzyme in human cancer diseases.

Gou Qi Zi inhibits proliferation and induces apoptosis through the PI3K/AKT1 signaling pathway in non-small cell lung cancer

Background

Gou Qi Zi (Lycium barbarum) is a traditional herbal medicine with antioxidative effects. Although Gou Qi Zi has been used to prevent premature aging and in the treatment of non-small cell lung cancer (NSCLC), its mechanism of action in NSCLC remains unclear. The present study utilized network pharmacology to assess the potential mechanism of action of Gou Qi Zi in the treatment of NSCLC.

Methods

The TCMSP, TCMID, SwissTargetPrediction, DrugBank, DisGeNET, GeneCards, OMIM and TTD databases were searched for the active components of Gou Qi Zi and their potential therapeutic targets in NSCLC. Protein-protein interaction networks were identified and the interactions of target proteins were analyzed. Involved pathways were determined by GO enrichment and KEGG pathway analyses using the Metascape database, and molecular docking technology was used to study the interactions between active compounds and potential targets. These results were verified by cell counting kit-8 assays, BrdU labeling, flow cytometry, immunohistochemistry, western blotting, and qRT-PCR.

Results

Database searches identified 33 active components in Gou Qi Zi, 199 predicted biological targets and 113 NSCLC-related targets. A network of targets of traditional Chinese medicine compounds and potential targets of Gou Qi Zi in NSCLC was constructed. GO enrichment analysis showed that Gou Qi Zi targeting of NSCLC was mainly due to the effect of its associated lipopolysaccharide. KEGG pathway analysis showed that Gou Qi Zi acted mainly through the PI3K/AKT1 signaling pathway in the treatment of NSCLC. Molecular docking experiments showed that the bioactive compounds of Gou Qi Zi could bind to AKT1, C-MYC and TP53. These results were verified by experimental assays.

Conclusion

Gou Qi Zi induces apoptosis and inhibits proliferation of NSCLC in vitro and in vivo by inhibiting the PI3K/AKT1 signaling pathway.

Pluronic® F127 Thermoresponsive Viscum album Hydrogel: Physicochemical Features and Cellular In Vitro Evaluation

Viscum album L., popularly known as mistletoe, is well known for its anti-cancer properties, and the pharmaceutical application of hydroalcoholic dry extracts is still limited due to its low solubility in aqueous media, and physicochemical instability. The Pluronic® F127 is an amphiphilic polymer, which permits the solubilization of lipophilic and hydrophilic compounds. In this investigation, physicochemical features of hydrogel containing V. album dry extract (VADE-loaded-hydrogel) were performed by: dynamic light scattering (DLS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). VADE-loaded-hydrogel presented nanometer-size micelles with volume distribution ranging from 10.58 nm to 246.7 nm, and a polydispersity index of 0.441. The sample thermal analyses (TG and DSC) showed similar decomposition curves; however, the thermal events indicated an increase in thermal stability in relation to the presence of the extract. In addition to these interesting pharmaceutical features, IC50 values of 333.40 µg/mL and >1000 µg/mL were obtained when tumor (SCC-25) and non-tumor (L929) cells were incubated with VADE-loaded-hydrogel, respectively. The optical and ultrastructural cellular analysis confirmed the tumor selectivity since the following alterations were detected only in SCC-25 cells: disorganization of plasmatic membrane; an increase of cytoplasmatic vacuole size; alteration in the cristae mitochondrial shape; and generation of amorphous cellular material. These results emphasize the promising antitumoral potential of VADE-loaded-hydrogel as an herbal drug delivery system via in vitro assays.

Sulfur-Doped Organosilica Nanodots as a Universal Sensor for Ultrafast Live/Dead Cell Discrimination

Rapid and accurate differentiation between live and dead cells is highly desirable for the evaluation of cell viability. Here, we report the application of the orange-emitting sulfur-doped organosilica nanodots (S-OSiNDs) for ultrafast (30 s), ultrasensitive (1 μg/mL), and universal staining of the dead bacterial, fungal, and mammalian cells but not the live ones, which satisfies the requirements of a fluorescent probe that can specifically stain the dead cells. We further verify that the fluorescence distribution range of S-OSiNDs (which are distributed in cytoplasm and nucleus) is much larger than that of the commercial dead/fixed cell/tissue staining dye RedDot2 (which is distributed in the nucleus) in terms of dead mammalian cell staining, indicating that S-OSiNDs possess a better staining effect of dead cells than RedDot2. Overall, S-OSiNDs can be used as a robust fluorescent probe for ultrafast and accurate discrimination between dead and live cells at a single cell level, which may find a variety of applications in the biomedical field.

In Vitro Cytotoxicity and Spectral Analysis-Based Phytochemical Profiling of Methanol Extract of Barleria hochstetteri, and Molecular Mechanisms Underlying Its Apoptosis-Inducing Effect on Breast and Lung Cancer Cell Lines

The objectives of this research were to carry out GC–MS and LC–MS-based phytochemical profiling of Barleria hochstetteri, as well as flow cytometry-based mechanistic investigations of the cytotoxic effect of its extracts against breast and lung cancer cell lines. This preclinical in vitro study was carried out in Saudi Arabia and India, from 11 August to 15 January 2022. Barleria hochstetteri was sequentially extracted using the Soxhlet extraction technique. Utilizing LC–MS and GC–MS methods, the phytochemical profiling was performed. Additionally, the total phenolic compounds and flavonoids were quantified in the plant extract using spectrophotometric techniques. In this study, we first examined the cytotoxicity of the plant extract on non-malignant L929 cells and on the carcinogenic MCF-7 and A549 cell lines. Then, we studied the underlying molecular pathways by means of Anti-Bcl-2, caspase-3, and DNA fragmentation (TUNEL) assays, using flow cytometry. The results revealed phenolic compounds and flavonoids to be the two major components in the methanolic extract of B. hochstetteri, with concentrations of 3210 µg GAE/g dwt and 1863 µg QE/g dwt, respectively. Results from GC–MS and LC–MS analyses revealed the presence of bioactive phytochemicals with known cytotoxicity. From the MTT assay on cell viability, the IC50 of the methanol extract for the MCF-7 and A549 cell lines were 219.67 and 144.30 µg/mL, respectively. With IC50 values of 324.24 and 266.66 µg/mL, respectively, the aqueous and methanol extracts were less toxic when tested against the non-cancerous L929 cell line. The extract caused early and late apoptosis in the tested breast and lung cancer cells by activating caspase-3 and inhibiting Bcl-2 protein, and it also caused cell death via DNA damage, based on flow cytometric and molecular marker analyses. These findings indicate that the methanol extract of B. hochstetteri was cytotoxic on breast cancer and lung cancer cell lines. To uncover cancer-fighting chemicals, there is a need for further research on B. hochstetteri, as it is a promising source of anti-cancer chemotherapeutic drugs.

The Effect of Infant Gastric Digestion on Human Maternal Milk Cells

SCOPE

Human breast milk contains a variety of cell types that have potential roles in infant immunity and development. One challenge associates with defining the purpose(s) of milk cells in the infant is a poor understanding of the effect of digestion on cell fate.

METHODS AND RESULTS

This study first demonstrates that milk cell death occurs after gastric digestion in mice. Then flow cytometry and RT-PCR are used to understand the mechanism of human milk cell death and quantify live cell types before and after simulated gastric digestion. This study finds that digestion in simulated gastric fluid for 30 min reduces cell viability from 72% to 27%, with most cell death is caused by the acidic pH. The primary mechanism of cell death is caspase-mediated apoptosis. The non-cellular components of milk offer only mild protection against cell death from stomach acid.

CONCLUSIONS

Gastric digestion does not select for a specific resilient cell population to survive-most cell types die in equal proportions in the gastric environment. Taken together, these results provide a foundation with which to understand the fate of human breast milk cells in the infant's intestine and beyond.

Evaluation of fluorescence-based viability stains in cells dissociated from scleractinian coral Pocillopora damicornis

The application of established cell viability assays such as the commonly used trypan blue staining method to coral cells is not straightforward due to different culture parameters and different cellular features specific to mammalian cells compared to marine invertebrates. Using Pocillopora damicornis as a model, we characterized the autofluorescence and tested different fluorescent dye pair combinations to identify alternative viability indicators. The cytotoxicity of different representative molecules, namely small organic molecules, proteins and nanoparticles (NP), was measured after 24 h of exposure using the fluorescent dye pair Hoechst 33342 and SYTOX orange. Our results show that this dye pair can be distinctly measured in the presence of fluorescent proteins plus chlorophyll. P. damicornis cells exposed for 24 h to Triton-X100, insulin or titanium dioxide (TiO₂) NPs, respectively, at concentrations ranging from 0.5 to 100 µg/mL, revealed a LC50 of 0.46 µg/mL for Triton-X100, 6.21 µg/mL for TiO₂ NPs and 33.9 µg/mL for insulin. This work presents the approach used to customize dye pairs for membrane integrity-based cell viability assays considering the species- and genotype-specific autofluorescence of scleractinian corals, namely: endogenous fluorescence characterization followed by the selection of dyes that do not overlap with endogenous signals.

Phenotypic characteristics of peripheral immune cells of Myalgic encephalomyelitis/chronic fatigue syndrome via transmission electron microscopy: A pilot study

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex chronic multi-systemic disease characterized by extreme fatigue that is not improved by rest, and worsens after exertion, whether physical or mental. Previous studies have shown ME/CFS-associated alterations in the immune system and mitochondria. We used transmission electron microscopy (TEM) to investigate the morphology and ultrastructure of unstimulated and stimulated ME/CFS immune cells and their intracellular organelles, including mitochondria. PBMCs from four participants were studied: a pair of identical twins discordant for moderate ME/CFS, as well as two age- and gender- matched unrelated subjects-one with an extremely severe form of ME/CFS and the other healthy. TEM analysis of CD3/CD28-stimulated T cells suggested a significant increase in the levels of apoptotic and necrotic cell death in T cells from ME/CFS patients (over 2-fold). Stimulated Tcells of ME/CFS patients also had higher numbers of swollen mitochondria. We also found a large increase in intracellular giant lipid droplet-like organelles in the stimulated PBMCs from the extremely severe ME/CFS patient potentially indicative of a lipid storage disorder. Lastly, we observed a slight increase in platelet aggregation in stimulated cells, suggestive of a possible role of platelet activity in ME/CFS pathophysiology and disease severity. These results indicate extensive morphological alterations in the cellular and mitochondrial phenotypes of ME/CFS patients' immune cells and suggest new insights into ME/CFS biology.

Cell and body tissue physiology

This article discusses cell and tissue physiology and provides a basic review of their structure, function, and life cycle. Altered physiology is explored using clinical scenarios to give context to the aetiology of tumorigenesis.

Immunogenic Cell Death and Role of Nanomaterials Serving as Therapeutic Vaccine for Personalized Cancer Immunotherapy

Immunogenic cell death (ICD) is a rapidly growing research area representing one of the emerging therapeutic strategies of cancer immunotherapy. ICD is an umbrella term covering several cell death modalities including apoptosis, necroptosis, ferroptosis and pyroptosis, and is the product of a balanced combination of adjuvanticity (damage-associated molecular patterns and chemokines/cytokines) and antigenicity (tumor associated antigens). Only a limited number of anti-cancer therapies are available to induce ICD in experimental cancer therapies and even much less is available for clinical use. To overcome this limitation, nanomaterials can be used to increase the immunogenicity of cancer cells killed by anti-cancer therapy, which in themselves are not necessarily immunogenic. In this review, we outline the current state of knowledge of ICD modalities and discuss achievements in using nanomaterials to increase the immunogenicity of dying cancer cells. The emerging trends in modulating the immunogenicity of dying cancer cells in experimental and translational cancer therapies and the challenges facing them are described. In conclusion, nanomaterials are expected to drive further progress in their use to increase efficacy of anti-cancer therapy based on ICD induction and in the future, it is necessary to validate these strategies in clinical settings, which will be a challenging research area.

Photoactivatable Materials for Versatile Single-Cell Patterning Based on the Photocaging of Cell-Anchoring Moieties through Lipid Self-Assembly

Versatile methods for patterning multiple types of cells with single-cell resolution have become an increasingly important technology for cell analysis, cell-based device construction, and tissue engineering. Here, we present a photoactivatable material based on poly(ethylene glycol) (PEG)-lipids for patterning a variety of cells, regardless of their adhesion abilities. In this study, PEG-lipids bearing dual fatty acid chains were first shown to perfectly suppress cell anchoring on their coated substrate surfaces whereas those with single-chain lipids stably anchored cells through lipid-cell membrane interactions. From this finding, a PEG-lipid with one each of both normal and photocleavable fatty acid chains was synthesized as a material that could convert the chain number from two to one by exposure to light. On the photoconvertible PEG-lipid surface, cell anchoring was activated by light exposure. High-speed atomic force microscopy measurements revealed that this photocaging of the lipid-cell membrane interaction occurs because the hydrophobic dual chains self-assemble into nanoscale structures and cooperatively inhibit the anchoring. Light-induced dissociation of the lipid assembly achieved the light-guided fine patterning of multiple cells through local photoactivation of the anchoring interactions. Using this surface, human natural killer cells and leukemia cells could be positioned to interact one-by-one. The cytotoxic capacity of single immune cells was then monitored via microscopy, showing the proof-of-principle for applications in the high-throughput analysis of the heterogeneity in individual cell-cell communications. Thus, the substrate coated with our photoactivatable material can serve as a versatile platform for the accurate and rapid patterning of multiple-element cells for intercellular communication-based diagnostics.

Programmed cell death detection methods: a systematic review and a categorical comparison

Programmed cell death is considered a key player in a variety of cellular processes that helps to regulate tissue growth, embryogenesis, cell turnover, immune response, and other biological processes. Among different types of cell death, apoptosis has been studied widely, especially in the field of cancer research to understand and analyse cellular mechanisms, and signaling pathways that control cell cycle arrest. Hallmarks of different types of cell death have been identified by following the patterns and events through microscopy. Identified biomarkers have also supported drug development to induce cell death in cancerous cells. There are various serological and microscopic techniques with advantages and limitations, that are available and are being utilized to detect and study the mechanism of cell death. The complexity of the mechanism and difficulties in distinguishing among different types of programmed cell death make it challenging to carry out the interventions and delay its progression. In this review, mechanisms of different forms of programmed cell death along with their conventional and unconventional methods of detection of have been critically reviewed systematically and categorized on the basis of morphological hallmarks and biomarkers to understand the principle, mechanism, application, advantages and disadvantages of each method. Furthermore, a very comprehensive comparative analysis has been drawn to highlight the most efficient and effective methods of detection of programmed cell death, helping researchers to make a reliable and prudent selection among the available methods of cell death assay. Conclusively, how programmed cell death detection methods can be improved and can provide information about distinctive stages of cell death detection have been discussed.

Alternariol ameliorates lung carcinoma via reprogramming cytokine signaling associated with PI3K/Akt cascade in vitro and in vivo

Objectives

The lung cancer is most frequently diagnosed cancer incidence worldwide. A large number of populations are heavily affected to this every year with poor prognosis.

Methods

Our study investigated the anticancer effect of alternariol, a secondary metabolite, on A549 lung cancer cell line and benzo-α-pyrene induced lung carcinoma model on balb/c mice. The cytotoxicity assay, DAPI staining and the flow cytometry was performed to assess the anticancer efficacy of alternariol in A549 lung cancer cell. For in vivo study the toxicity study was performed. The lung cancer was developed in the animals via intraperitoneal administration of benzo-α-pyrene and subsequently 2 weeks later alternariol treatment was carried out for 24 weeks. The chemotherapeutic effect of alternariol was assessed through histopathological analysis, followed by immunohistochemistry and in vivo antioxidant study.

Results

The in vitro data suggested a significant percentage of early and late apoptotic events in A549 cells with G0/G1 phase arrest which ultimately caused apoptosis followed by alternariol therapy. The in vivo study showed that alternariol therapy decreased the pulmonary fibrosis and formation of granuloma in lung tissue and restored the normal histopathological characteristics of lung. Furthermore, alternariol treatment downregulated the expression of PI3K, Akt and inflammatory mediators such as IL-6, TNF-α and increased the expression of apoptotic markers, p53.

Conclusion

In conclusion, the treatment with alternariol effectively decreased the progression of lung cancer through the inhibition of carcinogenic markers by reprogramming the p53/PI3K/Akt pathway and IL-6/TNF-α mediated cytokine signaling in mice.

The impact of transportation time on apoptosis in allogeneic stem cell grafts and the clinical outcome in malignant patients with unrelated donors

BACKGROUND

The quality of cells in peripheral blood stem cell (PBSC) grafts is important for allogeneic stem cell transplantation outcome. The viability of PBSC grafts may decrease during transportation time between donor and transplant center. We hypothesize that the graft viability based on apoptosis and necrosis in the graft may better reflect graft quality and clinical outcome.

METHODS

PBSC graft viability from unrelated donors was analyzed in 91 patients. Viable cells were defined as 7-aminoactinomycin D- and Annexin V-negative. The clinical outcome, including survival, transplant-related mortality and graft-versus-host disease (GvHD), was correlated to graft viability.

RESULTS

Grafts transported for 1 day had a median viability of 86.4% (range 63.8 to 98.9%), and grafts transported for 2 days had median viability of 83.2% (range 52.8% to 96.2%) (P = .003). Grafts were divided into two groups based on the median graft viability of 85.1%. Patients who received low viability grafts had lower 1-year survival of 63.7% compared with 88.9% for those who received high viability grafts (P = .007). In the multivariate analysis, transplant-related mortality (TRM) was higher in the low viability group (P = .03), whereas overall survival was not significantly associated with graft viability. The incidence of acute GvHD grade II to IV, chronic GvHD and relapse risk remained comparable between the groups.

CONCLUSION

Low graft viability was an independent predictor of 1-year survival and TRM after adjusting for multiple confounders. Better graft quality markers are important for the detection of clinically important variations in the stem cell graft.

Live-dead assay on unlabeled cells using phase imaging with computational specificity

Existing approaches to evaluate cell viability involve cell staining with chemical reagents. However, the step of exogenous staining makes these methods undesirable for rapid, nondestructive, and long-term investigation. Here, we present an instantaneous viability assessment of unlabeled cells using phase imaging with computation specificity. This concept utilizes deep learning techniques to compute viability markers associated with the specimen measured by label-free quantitative phase imaging. Demonstrated on different live cell cultures, the proposed method reports approximately 95% accuracy in identifying live and dead cells. The evolution of the cell dry mass and nucleus area for the labeled and unlabeled populations reveal that the chemical reagents decrease viability. The nondestructive approach presented here may find a broad range of applications, from monitoring the production of biopharmaceuticals to assessing the effectiveness of cancer treatments.

Common methods for characterising cell viability involve cell staining with chemical reagents. Here the authors report a method for cell viability assessment that does not require labelling; this uses quantitative phase imaging combined with deep learning.

Time-delayed effects of a single application of AgNPs on structure of testes and functions in Blaps polychresta Forskal, 1775 (Coleoptera: Tenebrionidae)

Silver nanoparticles (AgNPs) are currently the most frequently used engineered nanoparticles. The penetration of AgNPs into ecosystems is undeniable, and their adverse effects on organism reproduction are of fundamental importance for ecosystem stability. In this study, the survival time of the Egyptian beetle Blaps polychresta Forskal, 1775 (Coleoptera: Tenebrionidae), after a single application of 7 different doses, was calculated for 30 days. Then, for the group for which the effect on mortality was calculated as LOAEL - the Lowest Observed Adverse Effect Level, namely, 0.03 mg AgNPs/g body weight (b.w.t.), the following were assessed: structure and ultrastructure of gonads by TEM and SEM, cell viability by cytometry, DNA damage by the comet assay, and a variety of stress markers by spectrophotometric methods. A dose-dependent reduction in the survival time of the insects was revealed. Detailed analysis of the testes of beetles treated with 0.03 mg AgNPs/g b.w.t. revealed numerous adverse effects of nanoparticles in structure and ultrastructure, accompanied by increased apoptosis (but not necrosis), increased DNA damage, increased lipid peroxidation, and decreased levels of antioxidant enzymes. Most likely, the observed results are connected with the gradual release of Ag⁺ from the surface of the nanoparticles, which, once applied, are internalized in cells and become a long-lasting, stable source of Ag⁺ ions. Thus, a single exposure to AgNPs may have the effects of chronic exposure and lead to structural damage and dysfunction of the gonads of B. polychresta.

Cell Death in AMD: The Rationale for Targeting Fas

Age-related macular degeneration (AMD) is a leading cause of irreversible blindness in the developed world. While great advances have been made in the treatment of the neovascular (“wet”) form of the disease, there is still a significant need for therapies that prevent the vision loss associated with the advanced forms of dry, atrophic AMD. In this atrophic form, retinal pigment epithelial (RPE) and photoreceptor cell death is the ultimate cause of vision loss. In this review, we summarize the cell death pathways and their relation to RPE and retinal cell death in AMD. We review the data that support targeting programmed cell death through inhibition of the Fas receptor as a novel approach to preserve these structures and that this effect results from inhibiting both canonical death pathway activation and reducing the associated inflammatory response. These data lay the groundwork for current clinical strategies targeting the Fas pathway in this devastating disease.

Alternariol alleviates breast carcinoma by inhibiting cellular proliferation correlated with increased apoptotic events in rats

The breast cancer is most frequently diagnosed cancer in the women worldwide. Our study investigated the anticancer effect of alternariol, a secondary metabolite originated from endophytic fungi, against DMBA induced breast carcinoma on Wistar rats. The toxicity study investigated the LD50 and the subsequent doses of alternariol for the carcinogenic study. The breast cancer was developed in rats via induction of DMBA (5 mg/kg, i.v.) and the carcinogenic study was continued for 24 weeks. The induction of breast cancer and the chemotherapeutic effect of alternariol were assessed through histopathological analysis of rat mammary tissue, followed by immunohistochemical analysis, cell proliferation assay and apoptosis assay by TUNEL method. The result showed that alternariol therapy decreased the hyperplastic lesions of mammary tissue and restored the normal histopathological characteristics of breast tissue. Furthermore, alternariol treatment downregulated the expression of carcinogenic markers such as PI3K and Akt increased the expression of apoptotic markers including p53, caspase-3 and Bax. Alternariol therapy also decreased the cellular proliferation and enhanced the apoptotic events. In conclusion, the breast cancer progression was significantly reduced via induction of apoptotic events and inhibition of cell propagation which allowed constructing of suitable mechanism for alternariol mediated chemotherapeutic approach.

Quantitative Analysis of Apoptosis and Necrosis in Live Cells Using Flow Cytometry

Apoptosis and necrosis are the two sides of the cell death penumbra. Apoptosis is a well-studied model of cell death wherein the cell destroys itself employing a predefined form of active signaling without the release of soluble cytoplasmic contents to the external environment. Compared to apoptosis, necrosis is a nonspecific form of sudden cell death in response to an invasive external stimulus which in turn is devoid of active programmed intracellular signaling leading to the sudden release of the soluble cellular contents consequent to the rupture of the cell membrane. This fundamental difference between apoptosis and necrosis made us believe that the former is the safe form of cell death and the latter is an undesirable one which often elicits an inflammatory response to the adjacent cells. Recent studies have shown that necrosis also involves a few defined cellular and complex biochemical events similar to apoptosis rendering it difficult to distinguish these two events at the single-cell level using the currently used popular assays.Here we provide a newly described detailed methodology encompassing cell system development along with a multiparametric flow cytometry-based approach to discriminate apoptotic cells from necrotic cells using a stable cell line expressing genetically encoded probe for detecting caspase activation and DsRed targeted at the mitochondria.

The efficiency of photothermal action of gold shell-isolated nanoparticles against tumor cells depends on membrane interactions

Photoinduced hyperthermia with nanomaterials has been proven effective in photothermal therapy (PTT) of tumor tissues, but a precise control in PTT requires determination of the molecular-level mechanisms. In this paper, we determined the mechanisms responsible for the action of photoexcited gold shell-isolated nanoparticles (AuSHINs) in reducing the viability of MCF7 (glandular breast cancer) and especially A549 (lung adenocarcinoma) cells in vitro experiments, while the photoinduced damage to healthy cells was much smaller. The photoinduced effects were more significant than using other nanomaterials, and could be explained by the different effects from incorporating AuSHINs on Langmuir monolayers from lipid extracts of tumoral (MCF7 and A549) and healthy cells. The incorporation of AuSHINs caused similar expansion of the Langmuir monolayers, but Fourier-transform infrared spectroscopy (FTIR) data of Langmuir-Schaefer films (LS) indicated distinct levels of penetration into the monolayers. AuSHINs penetrated deeper into the A549 extract monolayers, affecting the vibrational modes of polar groups and carbon chains, while in MCF7 monolayers penetration was limited to the surroundings of the polar groups. Even smaller insertion was observed for monolayers of the healthy cell extract. The photochemical reactions were modulated by AuSHINs penetration, since upon irradiation the surface area of A549 monolayer decreased owing to lipid chain cleavage by oxidative reactions. For MCF7 monolayers, hydroperoxidation under illumination led to a ca. 5% increase in surface area. The monolayers of healthy cell lipid extract were barely affected by irradiation, consistent with the lowest degree of AuSHINs insertion. In summary, efficient photothermal therapy may be devised by producing AuSHINs capable of penetrating the chain region of tumor cell membranes.

Hexafluoropropylene oxide dimer acid (GenX) exposure induces apoptosis in HepG2 cells

Hexafluoropropylene oxide dimer acid, also known as GenX, is a poly- and perfluoroalkyl substance (PFAS). PFASs are nonvolatile synthetic substances that can be readily disseminated into the environment during processing and use, making them easy to implement in the soil, drinking water, and air. Compared to other PFASs, GenX has a comparatively short carbon chain length and is expected to have a lower tendency to accumulate in humans; therefore, GenX has recently been used as a substitute to other PFASs. However, the mechanisms underlying GenX action and intoxication in humans remains unclear. In this study, the apoptotic capacity of GenX in human liver cells was investigated. When representative human-derived liver cells (HepG2 cells) were treated with GenX for 12 h, cell viability was reduced, and apoptosis was greatly increased. In addition, GenX increased the generation of intracellular reactive oxygen species (ROS), indicating the induction of oxidative stress in a dose-dependent manner. GenX treatment increased the expression of major apoptosis-related genes relative to the untreated control group. This research indicates that GenX causes apoptosis through ROS mediation in HepG2 cells, which may expand our knowledge of the molecular and toxicological mechanisms of GenX.

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Hexafluoropropylene oxide dimer acid (GenX) can be harmful to the liver.

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Through the mediation of ROS, GenX causes apoptosis in HepG2 cells.

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GenX activates Bax, caspase 3/9, CHOP, and p53 via the apoptosis.

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The intrinsic pathway links GenX mode of action to apoptosis-related stimuli.