Efficient apoptosis requires feedback amplification of upstream apoptotic signals by effector caspase-3 or -7

Cedrol in ginger (Zingiber officinale) as a promising hair growth drug: The effects of oral and external administration on hair regeneration and its mechanism

Ginger is an important cooking spice and herb worldwide, and scientific research has gradually confirmed the effect of ginger on preventing hair loss. Cedrol (CE) is a small sesquiterpene molecule in ginger and its external administration (EA) has shown hope in promoting hair growth, and alternative administration mode has become a potential treatment scheme to improve the efficacy of CE. The purpose of this study is to evaluate the effects of oral administration (OA) and EA of CE on hair regeneration of C57BL/6 alopecia areata (AA) mice induced by cyclophosphamide (CP) and to clarify the potential hair growth mechanism of CE in AA model in vitro and in vivo. The results showed that CE-OA has a shorter hair-turning black time and faster hair growth rate, and can lessen hair follicle damage induced by CP and promote hair follicle cell proliferation. Its effect is superior to CE-EA. At the same time, CE can increase the cytokines IFN-γ, IL-2, and IL-7 in the serum of mice, and decrease the expression of adhesion factors ICAM-1 and ELAM-1, thus alleviating the immunosuppression induced by CP. Mechanism research shows that CE regulates the JAK3/STAT3 signaling pathway, activates the Wnt3α/β-catenin germinal center, and ameliorates oxidative stress induced by CP, thus promoting the proliferation of hair follicle cells and reversing AA. These results provide a theoretical basis for understanding the anti-AA mechanism of CE-OA, indicating that CE can be used as raw material for developing oral hair growth drugs.

NatB Protects Procaspase-8 from UBR4-Mediated Degradation and Is Required for Full Induction of the Extrinsic Apoptosis Pathway

N-terminal acetyltransferase B (NatB) is a major contributor to the N-terminal acetylome and is implicated in several key cellular processes including apoptosis and proteostasis. However, the molecular mechanisms linking NatB-mediated N-terminal acetylation to apoptosis and its relationship with protein homeostasis remain elusive. In this study, we generated mouse embryonic fibroblasts (MEFs) with an inactivated catalytic subunit of NatB (Naa20-/-) to investigate the impact of NatB deficiency on apoptosis regulation. Through quantitative N-terminomics, label-free quantification, and targeted proteomics, we demonstrated that NatB does not influence the proteostasis of all its substrates. Instead, our focus on putative NatB-dependent apoptotic factors revealed that NatB serves as a protective shield against UBR4 and UBR1 Arg/N-recognin-mediated degradation. Notably, Naa20-/- MEFs exhibited reduced responsiveness to an extrinsic pro-apoptotic stimulus, a phenotype that was partially reversible upon UBR4 Arg/N-recognin silencing and consequent inhibition of procaspase-8 degradation. Collectively, our results shed light on how the interplay between NatB-mediated acetylation and the Arg/N-degron pathway appears to impact apoptosis regulation, providing new perspectives in the field including in therapeutic interventions.

A General Molecular Structural Design for Highly Efficient Photopyroptosis that can be Activated within 10 s Irradiation

Photopyroptosis is an emerging research branch of photodynamic therapy (PDT), whereas there remains a lack of molecular structural principles to fabricate photosensitizers for triggering a highly efficient pyroptosis. Herein, a general and rational structural design principle to implement this hypothesis, is proposed. The principle relies on the clamping of cationic moieties (e.g., pyridinium, imidazolium) onto one photosensitive core to facilitate a considerable mitochondrial targeting (both of the inner and the outer membranes) of the molecules, thus maximizing the photogenerated reactive oxygen species (ROS) at the specific site to trigger the gasdermin E-mediated pyroptosis. Through this design, the pyroptotic trigger can be achieved in a minimum of 10 s of irradiation with a substantially low light dosage (0.4 J cm⁻2), compared to relevant work reported (up to 60 J cm⁻2). Moreover, immunotherapy with high tumor inhibition efficiency is realized by applying the synthetic molecules alone. This structural paradigm is valuable for deepening the understanding of PDT (especially the mitochondrial-targeted PDT) from the perspective of pyroptosis, toward the future development of the state-of-the-art form of PDT.

Injectable biodegradable microcarriers for iPSC expansion and cardiomyocyte differentiation

Cell therapy is a potential novel treatment for cardiac regeneration and numerous studies have attempted to transplant cells to regenerate the myocardium lost during myocardial infarction. To date, only minimal improvements to cardiac function have been reported. This is likely to be the result of low cell retention and survival following transplantation. This study aimed to improve the delivery and engraftment of viable cells by using an injectable microcarrier that provides an implantable, biodegradable substrate for attachment and growth of cardiomyocytes derived from induced pluripotent stem cells (iPSC). We describe the fabrication and characterisation of Thermally Induced Phase Separation (TIPS) microcarriers and their surface modification to enable iPSC-derived cardiomyocyte attachment in xeno-free conditions is described. The selected formulation resulted in iPSC attachment, expansion, and retention of pluripotent phenotype. Differentiation of iPSC into cardiomyocytes on the microcarriers is investigated in comparison with culture on 2D tissue culture plastic surfaces. Microcarrier culture is shown to support culture of a mature cardiomyocyte phenotype, be compatible with injectable delivery, and reduce anoikis. The findings from this study demonstrate that TIPS microcarriers provide a supporting matrix for culturing iPSC and iPSC-derived cardiomyocytes in vitro and are suitable as an injectable cell-substrate for cardiac regeneration.

Mechanisms of Arachidonic Acid In Vitro Schistosomicidal Potential

Arachidonic acid (ARA) was shown to possess safe and effective schistosomicidal impact on larval and adult Schistosoma mansoni and Schistosoma hematobium in vitro and in vivo in laboratory rodents and in children residing in low and high endemicity regions. We herein examine mechanisms underlying ARA schistosomicidal potential over two experiments, using in each pool a minimum of 50 adult male, female, or mixed-sex freshly recovered, ex vivo S. mansoni. Worms incubated in fetal calf serum-free medium were exposed to 0 or 10 mM ARA for 1 h at 37 °C and immediately processed for preparation of surface membrane and whole worm body homogenate extracts. Mixed-sex worms were additionally used for evaluating the impact of ARA exposure on the visualization of outer membrane cholesterol, sphingomyelin (SM), and ceramide in immunofluorescence assays. Following assessment of protein content, extracts of intact and ARA-treated worms were examined and compared for SM content, neutral sphingomyelinase activity, reactive oxygen species levels, and caspase 3/7 activity. Arachidonic acid principally led to perturbation of the organization, integrity, and SM content of the outer membrane of male and female worms and additionally impacted female parasites via stimulating neutral sphingomyelinase activity and oxidative stress. Arachidonic powerful action on female worms combined with its previously documented ovocidal activities supports its use as safe and effective therapy against schistosomiasis, provided implementation of the sorely needed and long waited-for chemical synthesis.

Photocrosslinked Co-Assembled Amino Acid Nanoparticles for Controlled Chemo/Photothermal Combined Anticancer Therapy

Nanostructures formed from the self-assembly of amino acids are promising materials in many fields, especially for biomedical applications. However, their low stability resulting from the weak noncovalent interactions between the amino acid building blocks limits their use. In this work, nanoparticles co-assembled by fluorenylmethoxycarbonyl (Fmoc)-protected tyrosine (Fmoc-Tyr-OH) and tryptophan (Fmoc-Trp-OH) are crosslinked by ultraviolet (UV) light irradiation. Two methods are investigated to induce the dimerization of tyrosine, irradiating at 254 nm or at 365 nm in the presence of riboflavin as a photo-initiator. For the crosslinking performed at 254 nm, both Fmoc-Tyr-OH and Fmoc-Trp-OH generate dimers. In contrast, only Fmoc-Tyr-OH participates in the riboflavin-mediated dimerization under irradiation at 365 nm. The participation of both amino acids in forming the dimers leads to more stable crosslinked nanoparticles, allowing also to perform further chemical modifications for cancer applications. The anticancer drug doxorubicin (Dox) is adsorbed onto the crosslinked nanoparticles, subsequently coated by a tannic acid-iron complex, endowing the nanoparticles with glutathione-responsiveness and photothermal properties, allowing to control the release of Dox. A remarkable anticancer efficiency is obtained in vitro and in vivo in tumor-bearing mice thanks to the combined chemo- and photothermal treatment.

The role of mitochondrial damage-associated molecular patterns in acute pancreatitis

Acute pancreatitis (AP) is one of the most common gastrointestinal tract diseases with significant morbidity and mortality. Current treatments remain unspecific and supportive due to the severity and clinical course of AP, which can fluctuate rapidly and unpredictably. Mitochondria, cellular power plant to produce energy, are involved in a variety of physiological or pathological activities in human body. There is a growing evidence indicating that mitochondria damage-associated molecular patterns (mtDAMPs) play an important role in pathogenesis and progression of AP. With the pro-inflammatory properties, released mtDAMPs may damage pancreatic cells by binding with receptors, activating downstream molecules and releasing inflammatory factors. This review focuses on the possible interaction between AP and mtDAMPs, which include cytochrome c (Cyt c), mitochondrial transcription factor A (TFAM), mitochondrial DNA (mtDNA), cardiolipin (CL), adenosine triphosphate (ATP) and succinate, with focus on experimental research and potential therapeutic targets in clinical practice. Preventing or diminishing the release of mtDAMPs or targeting the mtDAMPs receptors might have a role in AP progression.

Bioengineered Ionic Liquid for Catheter-Directed Tissue Ablation, Drug Delivery, and Embolization

Delivery of therapeutics to solid tumors with high bioavailability remains a challenge and is likely the main contributor to the ineffectiveness of immunotherapy and chemotherapy. Here, a catheter-directed ionic liquid embolic (ILE) is bioengineered to achieve durable vascular embolization, uniform tissue ablation, and drug delivery in non-survival and survival porcine models of embolization, outperforming the clinically used embolic agents. To simulate the clinical scenario, rabbit VX2 orthotopic liver tumors are treated showing successful trans-arterial delivery of Nivolumab and effective tumor ablation. Furthermore, similar results are also observed in human ex vivo tumor tissue as well as significant susceptibility of highly resistant patient-derived bacteria is seen to ILE, suggesting that ILE can prevent abscess formation in embolized tissue. ILE represents a new class of liquid embolic agents that can treat tumors, improve the delivery of therapeutics, prevent infectious complications, and potentially increase chemo- and immunotherapy response in solid tumors.

Sterigmatocystin induces autophagic and apoptotic cell death of liver cancer cells via downregulation of XIAP

XIAP, or the X-linked Inhibitor of Apoptosis Protein, is the most extensively studied member within the IAP gene family. It possesses the capability to impede apoptosis through direct inhibition of caspase activity. Various kinds of cancers overexpress XIAP to enable cancer cells to avoid apoptosis. Consequently, the inhibition of XIAP holds significant clinical implications for the development of anti-tumor medications and the treatment of cancer. In this study, sterigmatocystin, a natural compound obtained from the genus asperigillus, was demonstrated to be able to induce apoptotic and autophagic cell death in liver cancer cells. Mechanistically, sterigmatocystin induces apoptosis by downregulation of XIAP expression. Additionally, sterigmatocystin treatment induces cell cycle arrest, blocks cell proliferation, and slows down colony formation in liver cancer cells. Importantly, sterigmatocystin exhibits a remarkable therapeutic effect in a nude mice model. Our findings revealed a novel mechanism through which sterigmatocystin induces apoptotic and autophagic cell death of liver cancer cells by suppressing XIAP expression, this offers a promising therapeutic approach for treating liver cancer patients.

Role for Caspase-8 in the Release of IL-1β and Active Caspase-1 from Viable Human Monocytes during Toxoplasma gondii Infection

Monocytes are actively recruited to sites of infection and produce the potent proinflammatory cytokine IL-1β. We previously showed that IL-1β release during Toxoplasma gondii infection of primary human monocytes requires the NLRP3 inflammasome and caspase-1 but is independent of gasdermin D and pyroptosis. To investigate mechanisms of IL-1β release, we generated caspase-1, -4, -5, or -8 knockout (KO) THP-1 monocytic cells. Genetic ablation of caspase-1 or -8, but not caspase-4 or -5, decreased IL-1β release during T. gondii infection without affecting cell death. In contrast, TNF-α and IL-6 secretion were unperturbed in caspase-8 KO cells during T. gondii infection. Dual pharmacological inhibition of caspase-8 and RIPK1 in primary monocytes also decreased IL-1β release without affecting cell viability or parasite infection. Caspase-8 was also required for the release of active caspase-1 from T. gondii-infected cells and for IL-1β release during infection with the related apicomplexan parasite Neospora caninum. Surprisingly, caspase-8 deficiency did not impair synthesis or cleavage of pro-IL-1β, but resulted in the retention of mature IL-1β within cells. Generation of gasdermin E KO and ATG7 KO THP-1 cells revealed that the release of IL-1β was not dependent on gasdermin E or ATG7. Collectively, our data indicate that during T. gondii Infection of human monocytes, caspase-8 functions in a novel gasdermin-independent mechanism controlling IL-1β release from viable cells. This study expands on the molecular pathways that promote IL-1β in human immune cells and provides evidence of a role for caspase-8 in the mechanism of IL-1β release during infection.

Apoptotic signaling: Beyond cell death

Apoptosis is the best described form of regulated cell death, and was, until relatively recently, considered irreversible once particular biochemical points-of-no-return were activated. In this manuscript, we examine the mechanisms cells use to escape from a self-amplifying death signaling module. We discuss the role of feedback, dynamics, propagation, and noise in apoptotic signaling. We conclude with a revised model for the role of apoptosis in animal development, homeostasis, and disease.

Death and survival from executioner caspase activation

Executioner caspases are evolutionarily conserved regulators of cell death under apoptotic stress. Activated executioner caspases drive apoptotic cell death through cleavage of diverse protein substrates or pyroptotic cell death in the presence of gasdermin E. On the other hand, activation of executioner caspases can also trigger pro-survival and pro-proliferation signals. In recent years, a growing body of studies have demonstrated that cells can survive from executioner caspase activation in response to stress and that the survivors undergo molecular and phenotypic alterations. This review focuses on death and survival from executioner caspase activation, summarizing the role of executioner caspases in apoptotic and pyroptotic cell death and discussing the potential mechanism and consequences of survival from stress-induced executioner caspase activation.

Tumor integrin targeted theranostic iron oxide nanoparticles for delivery of caffeic acid phenethyl ester: preparation, characterization, and anti-myeloma activities

Multiple myeloma (MM) is characterized by the accumulation of malignant plasma cells preferentially in the bone marrow. Currently, emerging chemotherapy drugs with improved biosafety profiles, such as immunomodulatory agents and protease inhibitors, have been used in clinics to treat MM in both initial therapy or maintenance therapy post autologous hematopoietic stem cell transplantation (ASCT). We previously discovered that caffeic acid phenethyl ester (CAPE), a water-insoluble natural compound, inhibited the growth of MM cells by inducing oxidative stress. As part of our continuous effort to pursue a less toxic yet more effective therapeutic approach for MM, the objective of this study is to investigate the potential of CAPE for in vivo applications by using magnetic resonance imaging (MRI)-capable superparamagnetic iron oxide nanoparticles (IONP) as carriers. Cyclo (Arg-Gly-Asp-D-Phe-Cys) (RGD) is conjugated to IONP (RGD-IONP/CAPE) to target the overexpressed αvβ3 integrin on MM cells for receptor-mediated internalization and intracellular delivery of CAPE. A stable loading of CAPE on IONP can be achieved with a loading efficiency of 48.7% ± 3.3% (wt%). The drug-release studies indicate RGD-IONP/CAPE is stable at physiological (pH 7.4) and basic pH (pH 9.5) and subject to release of CAPE at acidic pH (pH 5.5) mimicking the tumor and lysosomal condition. RGD-IONP/CAPE causes cytotoxicity specific to human MM RPMI8226, U266, and NCI-H929 cells, but not to normal peripheral blood mononuclear cells (PBMCs), with IC50s of 7.97 ± 1.39, 16.75 ± 1.62, and 24.38 ± 1.71 μM after 72-h treatment, respectively. Apoptosis assays indicate RGD-IONP/CAPE induces apoptosis of RPMI8226 cells through a caspase-9 mediated intrinsic pathway, the same as applying CAPE alone. The apoptogenic effect of RGD-IONP/CAPE was also confirmed on the RPMI8226 cells co-cultured with human bone marrow stromal cells HS-5 in a Transwell model to mimic the MM microenvironment in the bone marrow. In conclusion, we demonstrate that water-insoluble CAPE can be loaded to RGD-IONP to greatly improve the biocompatibility and significantly inhibit the growth of MM cells in vitro through the induction of apoptosis. This study paves the way for investigating the MRI-trackable delivery of CAPE for MM treatment in animal models in the future.

Cytotoxicity of bismuth(III) dithiocarbamate derivatives by promoting a mitochondrial-dependent apoptotic pathway and suppressing MCF-7 breast adenocarcinoma cell invasion

We previously reported that the bismuth(III) dithiocarbamate derivative, bismuth diethyldithiocarbamate (1) exhibited greater cytotoxicity while inducing apoptosis via the intrinsic pathway in MCF-7 cells. We further evaluated the other bismuth(III) dithiocarbamate derivatives, Bi[S2CNR]3, with R = (CH2CH2OH)(iPr), (CH2)4, and (CH2CH2OH)(CH3), denoted as 2, 3, and 4, respectively, in the same MCF-7 cell line. 2-4 were found to exhibit IC50 values of 10.33 ± 0.06 µM, 1.07 ± 0.01 µM and 25.37 ± 0.12 µM, respectively, compared to that of cisplatin at 30.53 ± 0.23 µM. Apoptotic promotion via the mitochondrial-dependent pathway was due to the elevation of intracellular reactive oxygen species (ROS), promotion of caspases, release of cytochrome c, fragmentation of DNA, and results of staining assay observed in all compound-treated cells. 2-4 are also capable of suppressing MCF-7 cell invasion and modulate Lys-48 also Lys-63 linked polyubiquitination, leading to proteasomal degradation. Analysis of gene expression via qRT-PCR revealed their modulation, which supported all activities conducted upon treatment with 2-4. Altogether, bismuth dithiocarbamate derivatives, with bismuth(III) as the metal center bound to ligands, isopropyl ethanol, pyrrolidine, and methyl ethanol dithiocarbamate, are potential anti-breast cancer agents that induce apoptosis and suppress metastasis. Further studies using other breast cancer cell lines and in vivo studies are recommended to clarify the anticancer effects of these compounds.

A multiprotein signaling complex sustains AKT and mTOR/S6K activity necessary for the survival of cancer cells undergoing stress

Cancer cells encounter stresses during tumor progression and metastatic spread, however, how they survive these challenges is not fully understood. We now identify a mechanism for cancer cell survival through the discovery of a multiprotein signaling complex that includes the GTPase Cdc42, the Cdc42 GEF/effector protein Dock7, AKT, mTOR and the mTORC1 regulatory partners TSC1, TSC2, and Rheb. This pro-survival signaling complex sustains the activated state of AKT by preventing its dephosphorylation at Ser473 during serum starvation, resulting in a low but critical activation of a Raptor-independent mTOR/S6K activity. We demonstrate that the Dock7 DHR1 domain, previously of unknown function, is responsible for preserving AKT phosphorylation through an interaction requiring its C2-like motif. Collectively, these findings help address long-standing questions of how Cdc42 signals mTOR activation by elucidating the unique functions of its signaling partner Dock7 as an AKT regulator necessary for resistance to anoikis and apoptosis in cancer cells.

Ionizing radiation induces cells with past caspase activity that contribute to the adult organ in Drosophila and show reduced Loss of Heterozygosity

There is increasing recognition that cells may activate apoptotic caspases but not die, instead displaying various physiologically relevant consequences. Mechanisms that underlie the life-or-death decision in a cell that has activated apoptotic caspases, however, are incompletely understood. By optimizing a published reporter for past caspase activity, we were able to visualize cells that survived caspase activation specifically after exposure to ionizing radiation in Drosophila larval wing discs. We found that cells with X-ray-induced past active caspases (XPAC) did not arise at random but were born at specific locations within the developing wing imaginal discs of Drosophila larvae. Inhibiting key components of the apoptotic pathway decreased XPAC number, suggesting that apoptotic signaling is needed to induce XPAC cells. Yet, XPAC cells appeared in stereotypical patterns that did not follow the pattern of IR-induced apoptosis, suggesting additional controls at play. Functional testing identified the contribution of wingless (Drosophila Wnt1) and Ras signaling to the prevalence of XPAC cells. Furthermore, by following irradiated larvae into adulthood, we found that XPAC cells contribute to the adult wing. To address the relationship between XPAC and genome stability, we combined a reporter for past caspase activity with mwh, an adult marker for Loss of Heterozygosity (LOH). We found a lower incidence of LOH among XPAC compared to cells that did not activate the reporter for past caspase activity. In addition, at time points when wing disc cells are finishing DNA repair, XPAC cells show an anti-correlation with cells with unrepaired IR-induced double-stranded breaks. Our data suggest that non-lethal caspase activity safeguards the genome by facilitating DNA repair and reducing LOH after transient exposure to X-rays. These results identify a physiological role for non-lethal caspase activity during recovery from radiation damage.

Synthesis, molecular docking, and molecular dynamic simulation studies of new 1,3,4-thiadiazole derivatives as potential apoptosis inducers in A549 lung cancer cell line

1,3,4-Thiadiazoles are structures that are bioisosteres of 1,3,4-oxadiazole and pyrimidine ring, which are found in the structure of many drugs and anticancer active newly studied derivatives. In the past, high effect profiles have been observed in many molecules created, based on the anticancer effects of the 2-amino-1,3,4-thiadiazole (NSC 4728) molecule and acetazolamide molecules. Focusing on these molecules and evaluating them in terms of mechanistic effects, twelve new N-[5-((3,5-dichlorophenoxy) methyl]-1,3,4-thiadiazole derivatives (3a-3i) were synthesized and their biological activities were investigated in lung cancer cells. The anticancer effects of the compounds were evaluated on the A549 and L929 cell lines. Compound 3f, namely 2-[(5-chlorobenzotiyazol-2-yl)thio]-N-[5-[(3,5-dichlorophenoxy)methyl]-1,3,4-thiadiazol-2-yl]acetamide, showed better activity than cisplatin, exhibiting high inhibitory potency (IC50: <0.98 μg/mL) and selectivity against A549 cell line even at the lowest concentration tested. Compounds 3c, 3f, and 3h with the lowest IC50 values of the compounds exhibited an excellent percentage of apoptosis between 72.48 and 91.95% compared to cisplatin. The caspase-3 activation and mitochondrial membrane potential change of the aforementioned three compounds were also studied. Moreover, matrix metalloproteinase-9 (MMP-9) inhibition potential of all final compounds was also investigated and IC50 values for compounds 3b and 3g were identified as 154.23 and 107.28 µM. Molecular docking and molecular dynamic simulation studies for MMP-9 enzyme inhibition were realized on these compounds and the nitrogen atoms of amide and thiadiazole moieties' ascertained that they play a key role in chelating with Zn metal, at the same time, (thio)ether moieties allow conformational change resulting in the ligand can make more stable contacts.Communicated by Ramaswamy H. Sarma.

Mitigative potential of kaempferide against polyethylene microplastics induced testicular damage by activating Nrf-2/Keap-1 pathway

Polyethylene microplastics (PE-MPs) are one of the environmental contaminants that instigate oxidative stress (OS) in various organs of the body, including testes. Kaempferide (KFD) is a plant-derived natural flavonol with potential neuroprotective, hepatoprotective, anti-cancer, anti-oxidant and anti-inflammatory properties. Therefore, the present study was designed to evaluate the alleviative effects of KFD against PE-MPs-prompted testicular toxicity in rats. Fourty eight adult male albino rats were randomly distributed into 4 groups: control, PE-MPs-administered (1.5 mgkg-1), PE-MPs (1.5 mgkg-1) + KFD (20 mgkg-1) co-treated and KFD (20 mgkg-1) only treated group. PE-MPs intoxication significantly (P < 0.05) lowered the expression of Nrf-2 and anti-oxidant enzymes, while increasing the expression of Keap-1. The activities of anti-oxidants i.e., catalase (CAT), glutathione reductase (GSR), superoxide dismutase (SOD), hemeoxygene-1 (HO-1) and glutathione peroxidase (GPx) were reduced, besides malondialdehyde (MDA) and reactive oxygen species (ROS) contents were increased significantly (P < 0.05) following the PE-MPs exposure. Moreover, PE-MPs exposure significantly (P < 0.05) reduced the sperm motility, viability and count, whereas considerably (P < 0.05) increased the dead sperm number and sperm structural anomalies. Furthermore, PE-MPs remarkably (P < 0.05) decreased steroidogenic enzymes and Bcl-2 expression, while increasing the expression of Caspase-3 and Bax. PE-MPs exposure significantly (P < 0.05) reduced the levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone, whereas inflammatory indices were increased. PE-MPs exposure also induced significant histopathological damages in the testes. Nevertheless, KFD supplementation significantly (P < 0.05) abrogated all the damages induced by PE-MPs. The findings of our study demonstrated that KFD could significantly attenuate PE-MPs-instigated OS and testicular toxicity, due to its anti-oxidant, anti-inflammatory, androgenic and anti-apoptotic potential.

Proteomic analysis discovers potential biomarkers of early traumatic axonal injury in the brainstem

OBJECTIVE

Application of Tandem Mass Tags (TMT)-based LC-MS/MS analysis to screen for differentially expressed proteins (DEPs) in traumatic axonal injury (TAI) of the brainstem and to predict potential biomarkers and key molecular mechanisms of brainstem TAI.

METHODS

A modified impact acceleration injury model was used to establish a brainstem TAI model in Sprague-Dawley rats, and the model was evaluated in terms of both functional changes (vital sign measurements) andstructural changes (HE staining, silver-plating staining and β-APP immunohistochemical staining). TMT combined with LC-MS/MS was used to analyse the DEPs in brainstem tissues from TAI and Sham groups. The biological functions of DEPs and potential molecular mechanisms in the hyperacute phase of TAI were analysed by bioinformatics techniques, and candidate biomarkers were validated using western blotting and immunohistochemistry on brainstem tissues from animal models and humans.

RESULTS

Based on the successful establishment of the brainstem TAI model in rats, TMT-based proteomics identified 65 DEPs, and bioinformatics analysis indicated that the hyperacute phase of TAI involves multiple stages of biological processes including inflammation, oxidative stress, energy metabolism, neuronal excitotoxicity and apoptosis. Three DEPs, CBR1, EPHX2 and CYP2U1, were selected as candidate biomarkers and all three proteins were found to be significantly expressed in brainstem tissue 30 min-7 days after TAI in both animal models and humans.

CONCLUSION

Using TMT combined with LC-MS/MS analysis for proteomic study of early TAI in rat brainstem, we report for the first time that CBR1, EPHX2 and CYP2U1 can be used as biomarkers of early TAI in brainstem by means of western blotting and immunohistochemical staining, compensating for the limitations of silver-plating staining and β-APP immunohistochemical staining, especially in the case of very short survival time after TAI (shorter than 30 min). A number of other proteins that also have a potential marker role are also presented, providing new insights into the molecular mechanisms, therapeutic targets and forensic identification of early TAI in brainstem.

New aryl-/heteroarylpiperazine derivatives of 1,7-dimethyl-8,9-diphenyl-4-azatricyclo[5.2.1.02,6]dec-8-ene-3,5,10-trione: Synthesis and preliminary studies of biological activities

Compounds containing dicarboximide skeleton such as succinimides, maleimides, glutarimides, and phthalimides possess broad biological properties including anti-fungal, antibacterial, antidepressant, or analgesic activities. The piperazine ring is found in a wide range of molecules that have demonstrated a variety of biological functions such as anticancer action and 5-HT receptors agonist/antagonist activity. In the present study, we combined both structures to develop new antitumor agents, a series of piperazine derivatives of 1,7-dimethyl-8,9-diphenyl-4-azatricyclo[5.2.1.02,6]dec-8-ene-3,5,10-trione and evaluated their biological activity. The structures of all tested compounds were confirmed by 1H and 13C NMR and by ESI MS spectral analysis. Their cytotoxicity was assessed in vitro against eight human cancer cell lines, namely prostate (PC3), colon (HCT116, SW480, SW620), leukemia (K562), liver (HepG2), lung (A549) and breast (MDA-Mb-231) in contrast to normal HMEC-1 cell line, by using MTT and Trypan blue method. The tested compounds showed significant activity toward cancer cells. The most pronounced cytotoxic effect was observed in K562 and HCT116 with IC50 values below 10 μM for all studied compounds. Importantly, the most promising derivatives for each cancer cell line (IC50 < 10 μM) exerted a weaker cytotoxic effect toward normal HMEC-1 cells than cancer cells. The evaluation of proapoptotic and inhibitory effects on IL-6 release showed that K562 and HCT116 cells were more sensitive to studied compounds than other cancer cell lines. Furthermore, for all piperazine derivatives, the functional activities at the 5-HT1A, D2 receptors as well as their binding affinities at the 5-HT2A, H1 and M receptors, were determined. The current investigation was able to successfully design compounds with both serotoninergic and anticancer properties. It serves as a good starting point for a multimodal approach for the management of cancer and cancer-related symptoms.

Colistin Effects on Emphysematous Lung in an LPS-Sepsis Model

Emphysema is prevalent in various respiratory diseases like Chronic Obstructive Pulmonary Disease (COPD) and cystic fibrosis. Colistin and vasoconstrictive drugs are crucial for treating these patients when diagnosed with sepsis in the ICU. This study examines colistin impact in ether-induced emphysematous septic and non-septic animals, focusing on lung pathophysiology and inflammatory responses, including IL-1β, TNF-α, AMPK, caspase-3, cyclin-D1, and colistin levels in lung tissue. All animals exhibited significant emphysematous changes, accentuated by LPS-induced septic conditions, validating the emphysema model and highlighting the exacerbating effect of sepsis on lung pathology. Colistin, alone or with vasoconstrictive drugs, stimulated immune responses through increased inflammatory cell infiltration and the presence of lymphocytes, indicating potential immunomodulatory effects. Vasoconstriction did not alter the effects of colistin or sepsis but correlated with increased colistin levels in the lungs of septic animals. These observations suggest a potential interplay between vasoconstrictive drugs and colistin distribution/metabolism, leading to enhanced local concentrations of colistin in the lung microenvironment. The findings suggest the need for further investigations to optimize colistin and vasoconstrictive drug delivery in critically ill patients with lung pathologies. Understanding these complexities may guide more effective management of inflammatory responses and lung pathologies in these critical conditions.

Apoptotic signaling clears engineered Salmonella in an organ-specific manner

Pyroptosis and apoptosis are two forms of regulated cell death that can defend against intracellular infection. When a cell fails to complete pyroptosis, backup pathways will initiate apoptosis. Here, we investigated the utility of apoptosis compared to pyroptosis in defense against an intracellular bacterial infection. We previously engineered Salmonella enterica serovar Typhimurium to persistently express flagellin, and thereby activate NLRC4 during systemic infection in mice. The resulting pyroptosis clears this flagellin-engineered strain. We now show that infection of caspase-1 or gasdermin D deficient macrophages by this flagellin-engineered S. Typhimurium induces apoptosis in vitro. Additionally, we engineered S. Typhimurium to translocate the pro-apoptotic BH3 domain of BID, which also triggers apoptosis in macrophages in vitro. During mouse infection, the apoptotic pathway successfully cleared these engineered S. Typhimurium from the intestinal niche but failed to clear the bacteria from the myeloid niche in the spleen or lymph nodes. In contrast, the pyroptotic pathway was beneficial in defense of both niches. To clear an infection, cells may have specific tasks that they must complete before they die; different modes of cell death could initiate these 'bucket lists' in either convergent or divergent ways.

Targeted Inhibition of Hsp90 in Combination with Metformin Modulates Programmed Cell Death Pathways in A549 Lung Cancer Cells

The pathophysiology of lung cancer is dependent on the dysregulation in the apoptotic and autophagic pathways. The intricate link between apoptosis and autophagy through shared signaling pathways complicates our understanding of how lung cancer pathophysiology is regulated. As drug resistance is the primary reason behind treatment failure, it is crucial to understand how cancer cells may respond to different therapies and integrate crosstalk between apoptosis and autophagy in response to them, leading to cell death or survival. Thus, in this study, we have tried to evaluate the crosstalk between autophagy and apoptosis in A549 lung cancer cell line that could be modulated by employing a combination therapy of metformin (6 mM), an anti-diabetic drug, with gedunin (12 µM), an Hsp90 inhibitor, to provide insights into the development of new cancer therapeutics. Our results demonstrated that metformin and gedunin were cytotoxic to A549 lung cancer cells. Combination of metformin and gedunin generated ROS and promoted MMP loss and DNA damage. The combination further increased the expression of AMPKα1 and promoted the nuclear localization of AMPKα1/α2. The expression of Hsp90 was downregulated, further decreasing the expression of its clients, EGFR, PIK3CA, AKT1, and AKT3. Inhibition of the EGFR/PI3K/AKT pathway upregulated TP53 and inhibited autophagy. The combination was promoting nuclear localization of p53; however, some cytoplasmic signals were also detected. Further increase in the expression of caspase 9 and caspase 3 was observed. Thus, we concluded that the combination of metformin and gedunin upregulates apoptosis by inhibiting the EGFR/PI3K/AKT pathway and autophagy in A549 lung cancer cells.

Sedanolide Activates KEAP1-NRF2 Pathway and Ameliorates Hydrogen Peroxide-Induced Apoptotic Cell Death

Sedanolide is a bioactive compound with anti-inflammatory and antitumor activities. Although it has been recently suggested that sedanolide activates the nuclear factor E2-related factor 2 (NRF2) pathway, there is little research on its effects on cellular resistance to oxidative stress. The objective of the present study was to investigate the function of sedanolide in suppressing hydrogen peroxide (H2O2)-induced oxidative damage and the underlying molecular mechanisms in human hepatoblastoma cell line HepG2 cells. We found that sedanolide activated the antioxidant response element (ARE)-dependent transcription mediated by the nuclear translocation of NRF2. Pathway enrichment analysis of RNA sequencing data revealed that sedanolide upregulated the transcription of antioxidant enzymes involved in the NRF2 pathway and glutathione metabolism. Then, we further investigated whether sedanolide exerts cytoprotective effects against H2O2-induced cell death. We showed that sedanolide significantly attenuated cytosolic and mitochondrial reactive oxygen species (ROS) generation induced by exposure to H2O2. Furthermore, we demonstrated that pretreatment with sedanolide conferred a significant cytoprotective effect against H2O2-induced cell death probably due to preventing the decrease in the mitochondrial membrane potential and the increase in caspase-3/7 activity. Our study demonstrated that sedanolide enhanced cellular resistance to oxidative damage via the activation of the Kelch-like ECH-associated protein 1 (KEAP1)-NRF2 pathway.

Evaluation of the liver targeting and anti‑liver cancer activity of artesunate‑loaded and glycyrrhetinic acid‑coated nanoparticles

Globally, liver cancer ranks among the most lethal cancers, with chemotherapy being one of its primary treatments. However, poor selectivity, systemic toxicity, a narrow treatment window, low response rate and multidrug resistance limit its clinical application. Liver-targeted nanoparticles (NPs) exhibit excellent targeted delivery ability and promising effectivity in treating liver cancer. The present study aimed to investigate the liver-targeting and anti-liver cancer effect of artesunate (ART)-loaded and glycyrrhetinic acid (GA)-decorated polyethylene glycol (PEG)-poly (lactic-co-glycolic acid) (PLGA) (ART/GA-PEG-PLGA) NPs. GA-coated NPs significantly increased hepatoma-targeted cellular uptake, with micropinocytosis and caveolae-mediated endocytosis as its chief internalization pathways. Moreover, ART/GA-PEG-PLGA NPs exhibited pro-apoptotic effects on HepG2 cells, mainly via the induction of a high level of reactive oxygen species, decline in mitochondrial membrane potential and induction of cell cycle arrest. Additionally, ART/GA-PEG-PLGA NPs induced internal apoptosis pathways by upregulating the activity of cleaved caspase-3/7 and expression of cleaved poly (ADP-Ribose)-polymerase and Phos-p38 mitogen-activated protein kinase in HepG2 cells. Furthermore, ART/GA-PEG-PLGA NPs exhibited higher liver accumulation and longer mean retention time, resulting in increased bioavailability. Finally, ART/GA-PEG-PLGA NPs promoted the liver-targeting distribution of ART, increased the retention time and promoted its antitumour effects in vivo. Therefore, ART/GA-PEG-PLGA NPs afforded excellent hepatoma-targeted delivery and anti-liver cancer efficacy, and thus, they may be a promising strategy for treating liver cancer.

Tumor-targeted liposomes with platycodin D2 promote apoptosis in colorectal cancer

Conventional chemotherapy for colorectal cancer (CRC), though efficacious, is discouraging due to its limited targeting capability, lack of selectivity, and chemotherapy-associated side effects. With the advent of nanomedicines, a liposomal delivery system making use of a combination of anticancer phytochemicals is fast gaining popularity as one of the most promising nanoplatforms for CRC treatment. Rising evidence supports phytochemicals such as platycosides for their anticancer potency. To this end, a combination therapy including tumor-targeted liposomes along with phytochemicals might have a greater therapeutic potential against cancer. In this study, we developed acidity-triggered rational membrane (ATRAM) along with conjugated platycodin D2 (PCD2) and liposomes (PCD2-Lipo-ATRAM) as a tumor-targeting therapy. The PCD2-Lipo-ATRAM treatment demonstrated a successful tumor-targeting ability in the CRC xenografts, in which PCD2 not only exerted a potent antitumor effect by inducing apoptotic cell death and but also functioned as a liposome membrane stabilizer. Moreover, PCD2-Lipo-ATRAM suppressed antiapoptotic BCL-2 family proteins, resulting in enhanced cytotoxicity toward CRC cells by inducing intrinsic caspase-9/-3 mediated apoptosis. Thus, our data has shown that tumor-targeting PCD2-based liposomal systems represent a promising strategy for CRC therapy, since they directly target the tumors, unlike other therapies that can miss the target.

Anti-cancer potential of selenium-chitosan-polyethylene glycol-carvacrol nanocomposites in multiple myeloma U266 cells

Multiple myeloma (MM) is an incurable cancer that is characterized by malignant plasma cell proliferation. Approximately 10% of all blood cancers are MM, and there is no standard curative therapy. In this work, we intended to synthesize, characterize, and assess the anticancer effects of selenium/chitosan/polyethylene glycol-carvacrol nanocomposites (SCP-Car-NCs) on MM U266 cells in vitro. Various characterization techniques were used to characterize the synthesized SCP-Car-NCs. Several in vitro free radical scavenging experiments were conducted to test the ability of synthesized SCP-Car-NCs to scavenge the different free radicals. The cytotoxicity of SCP-Car-NCs was assessed on Vero and U266 cells using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay. By using various fluorescence staining techniques, the amount of reactive oxygen species (ROS) generation, MMP, and apoptosis were measured. Using commercial test kits, the levels of oxidative stress and apoptotic biomarkers in control and treated U266 cells were assessed. The highest peak in the UV spectral analysis was found to be at 271 nm, demonstrating the development of SCP-Car-NCs. Fourier transform infrared analysis showed that the synthesized SCP-Car-NCs contained a variety of stretching and bonding. The X-ray diffraction study confirmed the crystallinity of SCP-Car-NCs. The dynamic light scattering analysis showed that the SCP-Car-NCs had an average size of 171 nm. The different free radicals, such as the 2,2-diphenyl-1-picrylhydrazyl, hydroxyl, and peroxyl radicals, were significantly scavenged by the SCP-Car-NCs. According to the MTT assay results, the SCP-Car-NCs decreased the viability of U266 cells while having no impact on the proliferation of Vero cells. The SCP-Car-NCs significantly boosted ROS production, decreased the MMP level, and promoted apoptosis, as evidenced by the fluorescence staining experiments. In U266 cells treated with SCP-Car-NCs, the level of thiobarbituric acid reactive substances increased while superoxide dismutases and glutathione levels were reduced. In the SCP-Car-NCs treated U266 cells, it was found that the Bax, caspase-3, and -9 activities had increased while the Bcl-2 level had decreased. In conclusion, our findings show that SCP-Car-NCs treatment reduced the viability and increased apoptosis in the U266 cells, providing a new insight on SCP-Car-NCs' potential for usage in the future to treat MM.

Role of the YAP/TAZ-TEAD Transcriptional Complex in the Metabolic Control of TRAIL Sensitivity by the Mevalonate Pathway in Cancer Cells

Different studies have reported that inhibiting the mevalonate pathway with statins may increase the sensitivity of cancer cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), although the signaling mechanism leading to this sensitization remains largely unknown. We investigated the role of the YAP (Yes-associated protein)/TAZ (transcriptional co-activator with PDZ-binding motif)-TEAD (TEA/ATTS domain) transcriptional complex in the metabolic control of TRAIL sensitivity by the mevalonate pathway. We show that depleting nuclear YAP/TAZ in tumor cells, either via treatment with statins or by silencing YAP/TAZ expression with siRNAs, facilitates the activation of apoptosis by TRAIL. Furthermore, the blockage of TEAD transcriptional activity either pharmacologically or through the ectopic expression of a disruptor of the YAP/TAZ interaction with TEAD transcription factors, overcomes the resistance of tumor cells to the induction of apoptosis by TRAIL. Our results show that the mevalonate pathway controls cellular the FLICE-inhibitory protein (cFLIP) expression in tumor cells. Importantly, inhibiting the YAP/TAZ-TEAD signaling pathway induces cFLIP down-regulation, leading to a marked sensitization of tumor cells to apoptosis induction by TRAIL. Our data suggest that a combined strategy of targeting TEAD activity and selectively activating apoptosis signaling by agonists of apoptotic TRAIL receptors could be explored as a potential therapeutic approach in cancer treatment.

Syzygium cumini (L.) Extract-Derived Green Titanium Dioxide Nanoparticles Induce Caspase-Dependent Apoptosis in Hepatic Cancer Cells

An aqueous extract of Syzygium cumini seeds was utilized to green synthesize titanium dioxide nanoparticles (TiO2 NPs). UV-Visible, DLS, FTIR, XRD, FESEM, TEM, SAED, EDAX, and photoluminescence spectroscopy techniques were employed to characterize the prepared TiO2 nanoparticles. The rutile crystal structure of TiO2 NPs was revealed by XRD study. The TEM and FESEM images of the TiO2 NPs revealed an average particle size of 50-100 nm. We employed EDAX to investigate the elemental compositions of TiO2 NPs. The O-Ti-O stretching bands appeared in the FTIR spectrum of TiO2 NPs at wavenumbers of 495 cm-1. The absorption edge peaks of TiO2 NPs were found in the UV-vis spectra at 397 nm. The MTT study revealed that TiO2 NPs effectively inhibited the growth of liver cancer Hep3 and Hep-G2 cells. The results of the corresponding fluorescent staining assays showed that TiO2 NPs significantly increased ROS generation, decreased MMP, and induced apoptosis in both liver cancer Hep3 and Hep-G2 cells. TiO2 nanoparticles lessened SOD, CAT, and GSH levels while augmenting MDA contents in Hep3 and Hep-G2 cells. In both Hep3 and Hep-G2 cells treated with TiO2 NPs, the Bax, CytC, p53, caspase-3, -8, and -9 expressions were remarkably augmented, while Bcl-2 expression was reduced. Overall, these findings revealed that formulated TiO2 NPs treatment considerably inhibited growth and triggered apoptosis in Hep3 and HepG2 cells.

A CXCR4 inhibitor (balixafortide) enhances docetaxel-mediated antitumor activity in a murine model of prostate cancer bone metastasis

BACKGROUND

Prostate cancer (PCa) bone metastases have been shown to be more resistant to docetaxel than soft tissue metastases. The proinflammatory chemokine receptor CXCR4 has been shown to confer resistance to docetaxel (DOC) in PCa cells. Balixafortide (BLX) is a protein epitope mimetic inhibitor of CXCR4. Accordingly, we hypothesized that BLX would enhance DOC-mediated antitumor activity in PCa bone metastases.

METHODS

PC-3 luciferase-labeled cells were injected into the tibia of mice to model bone metastases. Four treatment groups were created: vehicle, DOC (5 mg/kg), BLX (20 mg/kg), and combo (receiving both DOC and BLX). Mice were injected twice daily subcutaneously with either vehicle or BLX starting on Day 1 and weekly intraperitoneally with DOC starting on Day 1. Tumor burden was measured weekly via bioluminescent imaging. At end of study (29 days), radiographs were taken of the tibiae and blood was collected. Serum levels of TRAcP, IL-2, and IFNγ levels were measured using ELISA. Harvested tibiae were decalcified and stained for Ki67, cleaved caspase-3, and CD34 positive cells or microvessels were quantified.

RESULTS

Tumor burden was lower in the combo group compared to the DOC alone group. Treatment with the combination had no impact on the number of mice with osteolytic lesions, however the area of osteolytic lesions was lower in the combo group compared to the vehicle and BLX groups, but not the DOC group. Serum TRAcP levels were lower in the combo compared to vehicle group, but not the other groups. No significant difference in Ki67 staining was found among the groups; whereas, cleaved caspase-3 staining was lowest in the Combo group and highest in the BLX group. The DOC and combo groups had more CD34+ microvessels than the control and BLX groups. There was no difference between the treatment groups for IL-2, but the combo group had increased levels of IFNγ compared to the DOC group.

CONCLUSIONS

Our data demonstrate that a combination of BAL and DOC has greater antitumor activity in a model of PCa bone metastases than either drug alone. These data support further evaluation of this combination in metastatic PCa.

Bifunctionalized Betulinic Acid Conjugates with C-3-Monodesmoside and C-28-Triphenylphosphonium Moieties with Increased Cancer Cell Targetability

A convenient synthesis is presented for a new class of bioactive bifunctionalized conjugates of lupane-type triterpenoids with triphenylphosphonium (TPP) and glycopyranosyl targeting moieties. The main synthesis steps include glycosylation of haloalkyl esters of the triterpene acid at the C-3 position by the imidate derivatives of glycopyranose followed by the product modification at the C-28 position with triphenylphosphine. The conjugates of betulinic acid (BetA) with TPP and d-glucose, l-rhamnose, or d-mannose moieties were thus synthesized as potential next-generation BetA-derived anticancer compounds. LC-MS/MS analysis in glucose-free physiological solution indicated that the glycosides showed better accumulation in PC-3 prostate cancer cells than both BetA and TPP-BetA conjugate, while the transporting effect of monosaccharide residues increased as follows: d-mannose < l-rhamnose ≈ d-glucose. At saturated concentrations, the glycosides caused a disturbing effect on mitochondria with a more drastic drop in transmembrane potential but weaker overproduction of mitochondrial reactive oxygen species (ROS) compared to TPP-BetA conjugate. Cytotoxicity of the glycosides in culture medium was comparable with or higher than that of the nonglycosylated conjugate, depending on the cancer cell line, whereas the compounds were less active toward primary fibroblasts. Glycosylation tended to increase pro-apoptotic and decrease pro-autophagic activities of the BetA derivatives. Cytotoxicity of the synthesized glycosides was considered in comparison with the summarized data on the natural and modified BetA glycosides. The results obtained are important for the development of bifunctionalized conjugates of triterpenoids with an increased cancer cell targetability.

Apoptotic signaling clears engineered Salmonella in an organ-specific manner

Pyroptosis and apoptosis are two forms of regulated cell death that can defend against intracellular infection. Although pyroptosis and apoptosis have distinct signaling pathways, when a cell fails to complete pyroptosis, backup pathways will initiate apoptosis. Here, we investigated the utility of apoptosis compared to pyroptosis in defense against an intracellular bacterial infection. We previously engineered Salmonella enterica serovar Typhimurium to persistently express flagellin, and thereby activate NLRC4 during systemic infection in mice. The resulting pyroptosis clears this flagellin-engineered strain. We now show that infection of caspase-1 or gasdermin D deficient macrophages by this flagellin-engineered S. Typhimurium induces apoptosis in vitro. Additionally, we also now engineer S. Typhimurium to translocate the pro-apoptotic BH3 domain of BID, which also triggers apoptosis in macrophages in vitro. In both engineered strains, apoptosis occurred somewhat slower than pyroptosis. During mouse infection, the apoptotic pathway successfully cleared these engineered S. Typhimurium from the intestinal niche, but failed to clear the bacteria in the myeloid niche in the spleen or lymph nodes. In contrast, the pyroptotic pathway was beneficial in defense of both niches. In order to clear an infection, distinct cell types may have specific tasks that they must complete before they die. In some cells, either apoptotic or pyroptotic signaling may initiate the same tasks, whereas in other cell types these modes of cell death may lead to different tasks that may not be identical in defense against infection. We recently suggested that such diverse tasks can be considered as different cellular 'bucket lists' to be accomplished before a cell dies.

Houttuynia cordata Thunb. Hexane fraction induces MDA-MB-231 cell apoptosis via caspases, ER stress, cell cycle arrest and attenuated Akt/ERK signaling

Houttuynia cordata Thunb. (HCT) is a perennial plant used in traditional Thai medicine for many centuries. This study aimed to investigate the antiproliferative effect of the hexane fraction, which has not been explored before. HCT ethanol extract (crude extract) was sequentially fractionated to obtain a hexane (H) fraction. GC-MS was used to determine the phytochemicals. The H fraction consisted of lipids, mainly α-linolenic acid and some terpenoids. MTT assay was used to determine the cytotoxic effects of H fraction in MCF-7, MDA-MB-231, NIH3T3 and PBMCs. The mode of cell death and cell cycle analysis were determined by flow cytometry. The mechanisms of cell death were defined by mitochondrial transmembrane potential (MTP) reduction and activation of caspase-3, -8 and -9. The expression levels of the Bcl-2 family, cell cycle-related, endoplasmic reticulum (ER) stress-associated proteins; and Akt/ERK signaling molecules were investigated by immunoblotting. The H fraction was toxic to MDA-MB-231 more than MCF-7 cells but not to NIH3T3 and PBMCs. The growth of MDA-MB-231 cells was inhibited through apoptosis. MTP was disrupted whereas caspase-3, -8 and -9 were activated. The expression of pro-apoptotic Bax and Bak was upregulated, while Bid and anti-apoptotic Bcl-xL proteins were downregulated. Cyclin D1 and CDK4 levels were downregulated. The cell cycle was arrested at G1. Moreover, GRP78 and CHOP elevation indicated ER stress-mediated pathway. The expression ratio of pAkt/Akt and pERK/ERK were reduced. Taken together, the molecular mechanisms of MDA-MB-231 cell apoptosis were via intrinsic/extrinsic pathways, cell cycle arrest, ER stress and abrogation of Akt/ERK survival pathways. According to the most current research, the H fraction may be used as an adjuvant in the BC treatment; however, before the anticancer strategy can be applied to patients, it is important to determine each active compound's effects in cell lines and in vivo when compared with a combined mixture.

Novel target for treatment of colorectal cancer: Metabolism and regulatory mechanisms of ferroptosis

Ferroptosis is a new type of programmed cell death charac-terized by intracellular iron overload and lipid peroxidation accumulation. In the past 10 years, research has demonstrated that intervention of ferroptosis can effectively prevent or treat cancer diseases, including colorectal cancer. However, the role of ferroptosis in different types of colorectal cancer is not the same. This article summarizes the three major pathways involved in the occurrence and development of ferroptosis, namely, iron metabolism, lipid metabolism, and amino acid metabolism, and discusses the specific mechanisms and clinical applications of ferroptosis targeted therapy in colorectal cancer of various consensus molecular subtypes. Existing studies have shown that ferroptosis targeted therapy has broad application prospects in optimizing the comprehensive treatment of colorectal cancer. This article will provide an important framework for studying the mechanism of ferroptosis in tumor prevention and treatment and have guiding significance in exploring the application of ferroptosis targeted therapy in the treatment of different types of colorectal cancer.

Geraniol suppresses tumour growth and enhances chemosensitivity of 5-fluorouracil on breast carcinoma in mice: involvement of miR-21/PTEN signalling

OBJECTIVES

Breast cancer is the most diagnosed cancer in females worldwide. Phytochemicals are among the recent compelling approaches showing anticancer activity. Geraniol is a monoterpenoid showing anti-tumoral potential in cell lines. However, its exact mechanism in breast cancer has not been elucidated. In addition, the possible chemosenstizing effect of geraniol when combined with chemotherapeutic drugs in breast carcinoma has not been previously addressed.

METHODS

Therefore, the aim of the current work is to investigate the potential therapeutic as well as chemosensitizing effects of geraniol on breast carcinoma induced in mice through examination of tumour biomarkers and histopathology profile.

KEY FINDINGS

Results showed a prominent suppression of tumour growth following geraniol treatment. This was accompanied with miR-21 downregulation that subsequently upregulated PTEN and suppressed mTOR levels. Geraniol was also able to activate apoptosis and inhibit autophagy. Histopathological examination revealed high necrosis areas separating malignant cells in the geraniol-treated group. Combined geraniol and 5-fluorouracil treatment induced more than 82% inhibition of tumour rate, surpassing the effect of each drug alone.

CONCLUSIONS

It can be concluded that geraniol could represent a promising avenue for breast cancer treatment as well as a potential sensitizing agent when combined with chemotherapeutic drugs.

Critical-Illness: Combined Effects of Colistin and Vasoactive Drugs: A Pilot Study

Colistin is often used as a last resort for treating multidrug-resistant infections, particularly in critically ill patients in intensive care units. Nonetheless, its side effects, including myopathy, require careful monitoring. Vasoconstrictive drugs are also used in intensive care to increase blood pressure and improve blood flow to vital organs, which can be compromised in critically ill patients. The exact mechanism of colistin-induced muscle toxicity is of significant interest due to its potential intensive-care clinical implications. Colistin alone or in combination with vasoconstrictive agents was administrated in non-septic and LPS-induced septic animals for 10 days. Histopathological evaluation of the gastrocnemius muscle and dot-blot protein tissue analysis were performed. Increased intramuscular area, de-organization of the muscle fibers and signs of myopathy were observed in colistin-treated animals. This effect was ameliorated in the presence of vasoconstrictive drugs. Administration of colistin to septic animals resulted in a decrease of AMPK and cyclin-D1 levels, while it had no effect on caspase 3 levels. Vasoconstrictive drugs' administration reversed the effects of colistin on AMPK and cyclin D1 levels. Colistin's effects on muscle depend on septic state and vasoconstriction presence, highlighting the need to consider these factors when administering it in critically ill patients.

Natural products modulate cell apoptosis: a promising way for treating endometrial cancer

Endometrial cancer (EC) is a prevalent epithelial malignancy in the uterine corpus's endometrium and myometrium. Regulating apoptosis of endometrial cancer cells has been a promising approach for treating EC. Recent in-vitro and in-vivo studies show that numerous extracts and monomers from natural products have pro-apoptotic properties in EC. Therefore, we have reviewed the current studies regarding natural products in modulating the apoptosis of EC cells and summarized their potential mechanisms. The potential signaling pathways include the mitochondria-dependent apoptotic pathway, endoplasmic reticulum stress (ERS) mediated apoptotic pathway, the mitogen-activated protein kinase (MAPK) mediated apoptotic pathway, NF-κB-mediated apoptotic pathway, PI3K/AKT/mTOR mediated apoptotic pathway, the p21-mediated apoptotic pathway, and other reported pathways. This review focuses on the importance of natural products in treating EC and provides a foundation for developing natural products-based anti-EC agents.

Apoptotic cell death in disease-Current understanding of the NCCD 2023

Apoptosis is a form of regulated cell death (RCD) that involves proteases of the caspase family. Pharmacological and genetic strategies that experimentally inhibit or delay apoptosis in mammalian systems have elucidated the key contribution of this process not only to (post-)embryonic development and adult tissue homeostasis, but also to the etiology of multiple human disorders. Consistent with this notion, while defects in the molecular machinery for apoptotic cell death impair organismal development and promote oncogenesis, the unwarranted activation of apoptosis promotes cell loss and tissue damage in the context of various neurological, cardiovascular, renal, hepatic, infectious, neoplastic and inflammatory conditions. Here, the Nomenclature Committee on Cell Death (NCCD) gathered to critically summarize an abundant pre-clinical literature mechanistically linking the core apoptotic apparatus to organismal homeostasis in the context of disease.

Synergistic anticancer activity of combined ATR and ribonucleotide reductase inhibition in Ewing's sarcoma cells

PURPOSE

Ewing's sarcoma is a highly malignant childhood tumour whose outcome has hardly changed over the past two decades despite numerous attempts at chemotherapy intensification. It is therefore essential to identify new treatment options. The present study was conducted to explore the effectiveness of combined inhibition of two promising targets, ATR and ribonucleotide reductase (RNR), in Ewing's sarcoma cells.

METHODS

Effects of the ATR inhibitor VE821 in combination with the RNR inhibitors triapine and didox were assessed in three Ewing's sarcoma cell lines with different TP53 status (WE-68, SK-ES-1, A673) by flow cytometric analysis of cell death, mitochondrial depolarisation and cell cycle distribution as well as by caspase 3/7 activity determination, by immunoblotting and by real-time RT-PCR. Interactions between inhibitors were evaluated by combination index analysis.

RESULTS

Single ATR or RNR inhibitor treatment produced small to moderate effects, while their combined treatment produced strong synergistic ones. ATR and RNR inhibitors elicited synergistic cell death and cooperated in inducing mitochondrial depolarisation, caspase 3/7 activity and DNA fragmentation, evidencing an apoptotic form of cell death. All effects were independent of functional p53. In addition, VE821 in combination with triapine increased p53 level and induced p53 target gene expression (CDKN1A, BBC3) in p53 wild-type Ewing's sarcoma cells.

CONCLUSION

Our study reveals that combined targeting of ATR and RNR was effective against Ewing's sarcoma in vitro and thus rationalises an in vivo exploration into the potential of combining ATR and RNR inhibitors as a new strategy for the treatment of this challenging disease.

Stress granule formation inhibits stress-induced apoptosis by selectively sequestering executioner caspases

Cytoplasmic stress granules (SGs) are phase-separated membrane-less organelles that form in response to various stress stimuli. SGs are mainly composed of non-canonical stalled 48S preinitiation complexes. In addition, many other proteins also accumulate into SGs, but the list is still incomplete. SG assembly suppresses apoptosis and promotes cell survival under stress. Furthermore, hyperformation of SGs is frequently observed in various human cancers and accelerates tumor development and progression by reducing stress-induced damage of cancer cells. Therefore, they are of clinical importance. However, the precise mechanism underlying SG-mediated inhibition of apoptosis remains ill-defined. Here, using a proximity-labeling proteomic approach, we comprehensively analyzed SG-resident proteins and identified the executioner caspases, caspase-3 and -7, as SG components. We demonstrate that accumulation of caspase-3/7 into SGs is mediated by evolutionarily conserved amino acid residues within their large catalytic domains and inhibits caspase activities and consequent apoptosis induced by various stresses. Expression of an SG-localization-deficient caspase-3 mutant in cells largely counteracted the anti-apoptotic effect of SGs, whereas enforced relocalization of the caspase-3 mutant to SGs restored it. Thus, SG-mediated sequestration of executioner caspases is a mechanism underlying the broad cytoprotective function of SGs. Furthermore, using a mouse xenograft tumor model, we show that this mechanism prevents cancer cells from apoptosis in tumor tissues, thereby promoting cancer progression. Our results reveal the functional crosstalk between SG-mediated cell survival and caspase-mediated cell death signaling pathways and delineate a molecular mechanism that dictates cell-fate decisions under stress and promotes tumorigenesis.

7-Geranyloxycinnamic Acid Isolated from Melicope lunu-ankenda Leaves Perturbs Colon Cancer and Breast Cancer Cell Lines' Growth via Induction of Apoptotic Pathway

Globally, breast cancer is the most prevalent form of cancer in women and there is a need for alternative therapies such as plant-derived compounds with low systemic toxicity and selective toxicity to cancer cells. The aim of this study is to assess the cytotoxicity effects of 7-geranyloxycinnamic acid isolated from leaves of Melicope lunu-ankenda, a traditional medicinal plant, on the human breast cancer cell lines. Dried leaf powder was used for the preparation of different crude extracts using different solvents of increasing order of polarity. The structure of the isolated compound from the petroleum ether extract was elucidated by ¹H and ¹³C NMR, LC-MS, and DIP-MS spectroscopy. The cytotoxic activity of the crude extract and 7-geranyloxycinnamic acid analyzed using MTT assay. Apoptotic analysis was evaluated using Annexin V-PI staining, AO/PI staining, intracellular ROS measurement, and measurement of activities of caspases 3/7, 8, and 9. Crude extracts and the isolated pure compound showed significant cytotoxicity against tested cancer cell lines. 7-geranyloxycinnamic acid was found to exert significant cytotoxic effects against breast cancer cell lines such as the MCF-7 and MDA-MB-231 cell lines. The cytotoxic effects are attributed to its ability to induce apoptosis via accumulation of ROS and activation of caspases in both breast cancer cell lines. The pure compound, 7-geranyloxycinnamic acid isolated from the leaves of M. lunu-ankenda, can exert significant cytotoxic effects against breast cancer cell lines without affecting the normal cells.

Pomiferin targets SERCA, mTOR, and P-gp to induce autophagic cell death in apoptosis-resistant cancer cells, and reverses the MDR phenotype in cisplatin-resistant tumors in vivo

Drug resistance in cancer has been classified as innate resistance or acquired resistance, which were characterized by apoptotic defects and ABC transporters overexpression respectively. Therefore, to preclude or reverse these resistance mechanisms could be a promising strategy to improve chemotherapeutic outcomes. In this study, a natural product from Osage Orange, pomiferin, was identified as a novel autophagy activator that circumvents innate resistance by triggering autophagic cell death via SERCA inhibition and activation of the CaMKKβ-AMPK-mTOR signaling cascade. In addition, pomiferin also directly inhibited the P-gp (MDR1/ABCB1) efflux and reversed acquired resistance by potentiating the accumulation and efficacy of the chemotherapeutic agent, cisplatin. In vivo study demonstrated that pomiferin triggered calcium-mediated tumor suppression and exhibited an anti-metastatic effect in the LLC-1 lung cancer-bearing mouse model. Moreover, as an adjuvant, pomiferin potentiated the anti-tumor effect of the chemotherapeutic agent, cisplatin, in RM-1 drug-resistant prostate cancer-bearing mouse model by specially attenuating ABCB1-mediated drug efflux, but not ABCC5, thereby promoting the accumulation of cisplatin in tumors. Collectively, pomiferin may serve as a novel effective agent for circumventing drug resistance in clinical applications.

AKR1B1 Represses Glioma Cell Proliferation through p38 MAPK-Mediated Bcl-2/BAX/Caspase-3 Apoptotic Signaling Pathways

This study aimed to investigate the regulatory role of Aldo-keto reductase family 1 member B1 (AKR1B1) in glioma cell proliferation through p38 MAPK activation to control Bcl-2/BAX/caspase-3 apoptosis signaling. AKR1B1 expression was quantified in normal human astrocytes, glioblastoma multiforme (GBM) cell lines, and normal tissues by using quantitative real-time polymerase chain reaction. The effects of AKR1B1 overexpression or knockdown and those of AKR1B1-induced p38 MAPK phosphorylation and a p38 MAPK inhibitor (SB203580) on glioma cell proliferation were determined using an MTT assay and Western blot, respectively. Furthermore, the AKR1B1 effect on BAX and Bcl-2 expression was examined in real-time by Western blot. A luminescence detection reagent was also utilized to identify the effect of AKR1B1 on caspase-3/7 activity. The early and late stages of AKR1B1-induced apoptosis were assessed by performing Annexin V-FITC/PI double-staining assays. AKR1B1 expression was significantly downregulated in glioma tissues and GBM cell lines (T98G and 8401). Glioma cell proliferation was inhibited by AKR1B1 overexpression but was slightly increased by AKR1B1 knockdown. Additionally, AKR1B1-induced p38 MAPK phosphorylation and SB203580 reversed AKR1B1's inhibitory effect on glioma cell proliferation. AKR1B1 overexpression also inhibited Bcl-2 expression but increased BAX expression, whereas treatment with SB203580 reversed this phenomenon. Furthermore, AKR1B1 induced caspase-3/7 activity. The induction of early and late apoptosis by AKR1B1 was confirmed using an Annexin V-FITC/PI double-staining assay. In conclusion, AKR1B1 regulated glioma cell proliferation through the involvement of p38 MAPK-induced BAX/Bcl-2/caspase-3 apoptosis signaling. Therefore, AKR1B1 may serve as a new therapeutic target for glioma therapy development.

Molecular superglue-mediated higher-order assembly of TRAIL variants with superior apoptosis induction and antitumor activity

Prompting higher-order death receptor (DR) clustering by increasing the valency of DR agonist is efficient to induce apoptosis of tumor cells. As an attractive DR agonist with superior biosafety, the trimeric tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) exerts limited antitumor effect in patients, which is predominantly attributed to its low DR clustering ability and short serum half-life. Previous antibody scaffolds-based engineering strategies to increase the valency and/or prolong the serum half-life of TRAIL improve apoptosis induction, however, often produce large proteins with poor tumor penetration. Covalent protein ligation mediated by small molecular superglues such as SpyTag/SpyCatcher might be a novel strategy to assemble higher-order TRAIL variants. Upon fusion to TRAIL promotor, SpyTag/SpyCatcher molecular superglue preferentially ligated two trimeric TRAIL to produce a hexameric TRAIL variant, HexaTR, exhibiting a significantly increased apoptosis induction. In addition, an albumin-binding HexaTR, ABD-HexaTR, with a prolonged serum half-life by binding to endogenous albumin was also produced using the same strategy. Compared to the trimeric TRAIL, the hexameric HexaTR and ABD-HexaTR showed 20-50 times greater in vivo antitumor effect, resulting in eradication of several types of large (150-300 mm³) tumor xenografts. Combination with bortezomib carried by liposome further improved the antitumor effects of the hexavalent HexaTR and ABD-HexaTR in refractory cancer. Our results indicate that the superglue-mediated higher-order assembly is promising to improve the DR clustering and proapoptotic signaling of TRAIL, showing great advantages in constructing the next generation of DR agonists for cancer therapy.

Upregulation of RIPK1 implicates in HEK 293T cell death upon transient transfection of A53T-α-synuclein

BACKGROUND

Alpha-synuclein (α-SN) is the central protein in synucleinopathies including Parkinson's disease. Nevertheless, the molecular mechanisms through which α-SN leads to neuronal death remain unclear.

METHODS

To elucidate the relationship between α-SN and apoptosis, some indicators of the intrinsic and extrinsic apoptotic cell death were assessed in normal and a stable HEK293T cell line expressing firefly luciferase after transfection with the wild-type (WT) and A53T mutant α-SN.

RESULTS

Opposite to WT-α-SN, overexpression of A53T-α-SN resulted in enhanced expression of almost two fold for RIPK1 (93.0 %), FADD (45 %), Caspase-8, and Casp-9 activity (52.0 %) in measured time. Transfection of both WT-α-SN and A53T-α-SN showed an increase in the Casp-3/Procasp-3 ratio (WT: 60.5 %; A53T: 41.0 %), Casp-3 activity (WT: 65.0 %; A53T: 20.5 %), and a decrease in luciferase activity (WT: 50 %; A53T: 34.8 %). Overexpression of A53T-α-SN brought about with more cell death percentage compared to WT-α-SN within 36 h. No significant alteration in cytochrome c and reactive oxygen species release into cytosol were observed for both WT-α-SN and A53T-α-SN.

CONCLUSION

Altogether, these findings highlight the link between disease related mutants of α-SN (like A53T-α-SN) in triggering of RIPK1-dependent extrinsic apoptotic pathway in cell death during neurodegeneration.

Caspase-6 is a key regulator of cross-talk signal way in PANoptosis in cancer

Cysteinyl aspartate specific proteinase (caspase)-6 belongs to the caspase family and plays a vital role in mediating cell death. Under certain conditions, three pathways of programmed cell death (PCD), including apoptosis, necroptosis and pyroptosis (PANoptosis), transform one way into another, with enormous therapeutic potential. Initially, scholars reported that caspase-6 is a caspase executor that mediates apoptosis. With the ceaseless exploration of the PCD types, studies have demonstrated that caspase-6 mediates pyroptosis by regulating gasdermin D and mediates necroptosis by regulating mixed lineage kinase domain-like. By regulating PANoptosis, caspase-6 plays a crucial role in tumorigenesis in humans and mediates anti-tumour immunity. Therefore, a comprehensive understanding of caspase-6 function in cancer via PANoptosis is important for the prevention and therapy of tumours. This article summarized the function of caspase-6 in PANoptosis and its impact on cancer development, providing targets and strategies for tumour treatment.

Chicken CH25H inhibits ALV-J replication by promoting cellular autophagy

Autophagy plays an important role in host antiviral defense. The avian leukosis virus subgroup J (ALV-J) has been shown to inhibit autophagy while promoting viral replication. The underlying autophagic mechanisms, however, are unknown. Cholesterol 25-hydroxylase (CH25H) is a conserved interferon-stimulated gene, which converts cholesterol to a soluble antiviral factor, 25-hydroxycholesterol (25HC). In this study, we further investigated the autophagic mechanism of CH25H resistance to ALV-J in chicken embryonic fibroblast cell lines (DF1). Our results found that overexpression of CH25H and treatment with 25HC promoted the autophagic markers microtubule-associated protein 1 light chain 3 II (LC3II) and autophagy-related gene 5(ATG5), while decreased autophagy substrate p62/SQSTM1 (p62) expression in ALV-J infection DF-1 cells. Induction of cellular autophagy also reduces the levels of ALV-J gp85 and p27. ALV-J infection, on the other hand, suppresses autophagic marker protein LC3II expression. These findings suggest that CH25H-induced autophagy is a host defense mechanism that aids in ALV-J replication inhibition. In particular, CH25H interacts with CHMP4B and inhibits ALV-J infection in DF-1 cells by promoting autophagy, revealing a novel mechanism by which CH25H inhibits ALV-J infection. Although the underlying mechanisms are not completely understood, CH25H and 25HC are the first to show inhibiting ALV-J infection via autophagy.

In Vivo Stable Allogenic Cartilage Regeneration in a Goat Model Based on Immunoisolation Strategy Using Electrospun Semipermeable Membranes

Tissue engineering is a promising strategy for cartilage defect repair. However, autologous cartilage regeneration is limited by additional trauma to the donor site and a long in vitro culture period. Alternatively, allogenic cartilage regeneration has attracted attention because of the unique advantages of an abundant donor source and immediate supply, but it will cause immune rejection responses (IRRs), especially in immunocompetent large animals. Therefore, a universal technique needs to be established to overcome IRRs for allogenic cartilage regeneration in large animals. In the current study, a hybrid synthetic-natural electrospun thermoplastic polyurethane/gelatin (TPU/GT) semipermeable membrane to explore the feasibility of stable allogenic cartilage regeneration by an immunoisolation strategy is developed. In vitro results demonstrated that the rationally designed electrospun TPU/GT membranes has ideal biocompatibility, semipermeability, and an immunoisolation function. In vivo results further showed that the semipermeable membrane (SPM) efficiently blocked immune cell attack, decreased immune factor production, and cell apoptosis of the regenerated allogenic cartilage. Importantly, TPU/GT-encapsulated cartilage-sheet constructs achieved stable allogeneic cartilage regeneration in a goat model. The current study provides a novel strategy for allogenic cartilage regeneration and supplies a new cartilage donor source to repair various cartilage defects.

Hallmarks and Biomarkers of Skin Senescence: An Updated Review of Skin Senotherapeutics

Aging is a complex process characterized by an ongoing decline in physiological functions, leading to degenerative diseases and an increased probability of death. Cellular senescence has been typically considered as an anti-proliferative process; however, the chronic accumulation of senescent cells contributes to tissue dysfunction and aging. In this review, we discuss some of the most important hallmarks and biomarkers of cellular senescence with a special focus on skin biomarkers, reactive oxygen species (ROS), and senotherapeutic strategies to eliminate or prevent senescence. Although most of them are not exclusive to senescence, the expression of the senescence-associated beta-galactosidase (SA-β-gal) enzyme seems to be the most reliable biomarker for distinguishing senescent cells from those arrested in the cell cycle. The presence of a stable DNA damage response (DDR) and the accumulation of senescence-associated secretory phenotype (SASP) mediators and ROS are the most representative hallmarks for senescence. Senotherapeutics based on natural compounds such as quercetin, naringenin, and apigenin have shown promising results regarding SASP reduction. These compounds seem to prevent the accumulation of senescent cells, most likely through the inhibition of pro-survival signaling pathways. Although studies are still required to verify their short- and long-term effects, these therapies may be an effective strategy for skin aging.