Cytotoxic Effects Research Articles

Evaluation of biological properties and phytochemical profile of Vitex trifolia L. extract and its infused oil as a value-added product for health promotion

Vitex trifolia L., a shrub plant, has long been used as a massage oil to treat a variety of ailments, particularly pain relief. Despite its long history of use, there has not been enough research done on its phytochemical profile and biological properties to validate its traditional use. Therefore, this current research aimed to evaluate its phytochemical profile and biological properties in two forms: Vitex trifolia L. ethanolic extract (VTE) and Vitex trifolia L. oil (VTO), which could be advantageous for clinical usage. Quality control of raw plant material, total phenolic, total flavonoid, and casticin of VTE and VTO were investigated. Furthermore, the antibacterial, antioxidant, and anti-inflammatory activities and cytotoxicity of VTE and VTO were evaluated. The study indicated that VTE contained more total phenolics (66.74±15.52 mg GAE/g), total flavonoids (29.68±2.05 mg CE/g extract), and casticin (2.45±0.02 mg/mL) than VTO. VTE consistently demonstrated stronger antibacterial, antioxidant, and anti-inflammatory properties than VTO. Taken together, VTE possessed remarkable antioxidant, anti-inflammatory, and antibacterial activities with no cytotoxic effects on cells. Even VTO had weak biological abilities. However, its stability testing revealed that the modestly accepted adjustments remained stable. Therefore, this study suggests that Vitex trifolia L. could be used as a natural product for health promotion and therapy.

Cavity Disinfection with Natural Agents and their Efficacy: A Review on Recent Literature

Abstract: The success of a dental restoration can be altered by the amount of residual bacteria present under the cavity which over time cause deterioration of adhesive cement by microleakage or secondary caries. Cavity disinfectant application on the cavity walls performs a cleansing action to decrease the bacterial load and improve the longevity of restorations. Although a wide variety of such chemical disinfectants have been in use, their cytotoxic effects have led to the increasing popularity of natural agents. These materials possess antimicrobial, antioxidant and anti-inflammatory properties, which effectively disinfect cavity walls while, at the same time, being cheaper, less toxic, and more patient-friendly. : Some of these agents have also been proven to improve the bond strength of resin to dentin by preventing collagen degradation and MMP inhibition. Propolis, aloe vera, chitosan, green tea, liquorice etc., are derived from parts of plants or animals and have been tested to be efficacious and, in some cases, superior to chemical alternatives without any erosive effect on dentin. : Although there is a lack of enough In vivo evidence to advocate the use of these products as an adjunct in dental therapy, recent studies have yielded promising results, which increases the scope for future clinical research. This review aims to highlight the properties and effectiveness of a few of such natural agents as potential cavity disinfectants.

Sesquiterpene coumarins with anti-vitiligo and cytotoxic activities from Ferula samarkandica

Two undescribed sesquiterpene coumarins (1–2) and eight known analogues (3–10) were isolated from the roots of Ferula samarkandica Korovin, growing in Uzbekistan. Their structures were established by comprehensive spectroscopic analysis including NMR, HRESIMS, UV and IR data. The absolute configurations were determined based on ECD calculations and confirmed by single-crystal X-ray diffraction analysis. Six compounds carrying 7′-carbonyl, 3′-carbonyl and 3′-acetoxy (4, 5, 6, 7, 9, 10) demonstrated anti-vitiligo potentials, in addition to five (4, 7, 8, 9, 10) with cytotoxic effects. Evaluation of anti-vitiligo activity in B16 cells revealed that compounds 4–7 and 9 exhibited promotion effects on melanin synthesis in B16 cells more potent than the positive control 8-methoxypsoralen (8-MOP), while 5, 7, 9 and 10 could also stimulate the tyrosinase activity superior to 8-MOP. Besides, compounds 4 and 7–10 also presented certain cytotoxic activities against HeLa, HT-29 and A549 cell lines, wherein 8 displayed a significant cytotoxicity against HT-29 cells with an IC50 value of 8.33 ± 0.34 μM.

Mechanistic evaluation of myristicin on apoptosis and cell cycle regulation in breast cancer cells.

The current study was focused on the anticancer activity of myristicin against MCF-7 human breast cancer (BC) cells. BC is the most common and leading malignant disease in women worldwide. Now-a-days, various conventional therapies are used against BC and still represent a chief challenge because those treatments fail to differentiate normal cells from malignant cells, and they have severe side effects also. So, there is a need develop new therapies to decrease BC-related morbidity and mortality. Myristicin, a 1‑allyl‑5‑methoxy‑3, 4‑methylenedioxybenzene, is a main active aromatic compound present in various spices, such as nutmeg, mace, carrot, cinnamon, parsely and some essential oils. Myristicin has a wide range of effects, including antitumor, antioxidative and antimicrobial activity. Nevertheless, the effects of myristicin on human BC cells remain largely unrevealed. The cytotoxicity effect of myristicin on MCF‑7 cells was increased dose dependently detected by (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Lactate Dehydrogenase assays. Myristicin was found to be significantly inducing the cell apoptosis, as compared to control, using acridine orange/ethidium bromide, Hoechst stain and annexin V. Moreover, it activates cell antimigration, intracellular reactive oxygen species generation and cell cycle arrest in the G1/S phase. In addition, myristicin induces the expression of apoptosis and cell cycle genes (Caspases8, Bax, Bid, Bcl2, PARP, p53, and Cdk1) was demonstrated by quantitative polymerase chain reaction and apoptosis proteins (c-PARP, Caspase 9, Cytochrome C, PDI) expression was also analyzed with western blot. Overall, we illustrated that myristicin could regulate apoptosis signaling pathways in MCF-7 BC cells.

Bee Venom Toxic Effect on MDA-MB-231 Breast Cancer Cells and Caenorhabditis Elegans.

Bee venom has therapeutics and pharmacological properties. Further toxicological studies on animal models are necessary due to the severe allergic reactions caused by this product. Here, Caenorhabditis elegans was used as an in vivo toxicity model, while breast cancer cells were used to evaluate the pharmacological benefits. The bee venom utilized in this research was collected from Apis mellifera species found in Northeast Brazil. The cytotoxicity caused by bee venom was measured by MTT assay on MDA-MB-231 and J774 A.1 cells during 24 - 72 hours of exposure. C. elegans at the L4 larval stage were exposed for three hours to M9 buffer or bee venom. Survival, behavioral parameters, reproduction, DAF-16 transcription factor translocation, the expression of superoxide dismutase (SOD), and metabolomics were analyzed. Bee venom suppressed the growth of MDA-MB-231 cancer cells and exhibited cytotoxic effects on macrophages. Also, decreased C. elegans survival impacted its behaviors by decreasing C. elegans feeding behavior, movement, and reproduction. Bee venom did not increase the expression of SOD-3, but it enhanced DAF-16 translocation from the cytoplasm to the nucleus. C. elegans metabolites differed after bee venom exposure, primarily related to aminoacyl- tRNA biosynthesis, glycine, serine and threonine metabolism, and sphingolipid and purine metabolic pathways. Our findings indicate that exposure to bee venom resulted in harmful effects on the cells and animal models examined. Thus, due to its potential toxic effect and induction of allergic reactions, using bee venom as a therapeutic approach has been limited. The development of controlled-release drug strategies to improve this natural product's efficacy and safety should be intensified.

1,3-Diaryl Triazenes Incorporating Disulfonamides Show Both Antiproliferative Activity and Effective Inhibition of Tumor-associated Carbonic Anhydrases IX and XII.

The aim of this study was to synthesize a library of novel di-sulfa drugs containing 1,3- diaryltriazene derivatives TS (1-13) by conjugation of diazonium salts of primary sulfonamides with sulfa drugs to investigate the cytotoxic effect of these new compounds in different cancer types and to determine their inhibitory activity against tumor-associated carbonic anhydrases IX and XII. A carbonic anhydrase inhibitory activity of the obtained compounds was evaluated against four selected human carbonic anhydrase isoforms (hCA I, hCA II, hCA IX and hCA XII) by a stoppedflow CO2 hydrase assay. In addition, in vitro, cytotoxicity studies were applied by using A549 (lung cancer), BEAS-2B (normal lung), MCF-7 (breast cancer), MDA-MB-231 (breast cancer), CRL-4010 (normal breast epithelium), HT-29 (colon cancer), and HCT -116 (colon cancer) cell lines. As a result of the inhibition data, the 4-aminobenzenesulfonamide derivatives were more active than their 3-aminobenzenesulfonamide counterparts. More specifically, compounds TS-1 and TS-2, both of which have primary sulfonamides on both sides of the triazene linker, showed the best inhibitory activity against hCA IX with Ki values of 19.5 and 13.7 nM and also against hCA XII with Ki values of 6.6 and 8.3 nM, respectively. In addition, in vitro cytotoxic activity on the human breast cancer cell line MCF-7 showed that some derivatives of di-sulfa triazenes, such as TS-5 and TS-13, were more active than SLC-0111. With the aim of developing more potent and isoform-selective CA inhibitors, these novel hybrid molecules containing sulfa drugs, triazene linkers, and the classical primary sulfonamide chemotype may be considered an interesting example of effective enzyme inhibitors and important anticancer agents.

Investigating the Effects of Dorema hyrcanum Root Extracts on Selective Induction of Programmed Cell Death in Glioblastoma, Ovarian Cancer and Breast Cancer Cell Lines.

Despite remarkable advances, cancer has remained the second cause of death, which shows that more potent novel compounds should be found. Ethnobotanical compounds have a long history of treating diseases, and several approved chemotherapeutic compounds were isolated from plants. The research aimed to evaluate the cytotoxic effects of Dorema hyrcanum root extract on ovarian, breast, and glioblastoma cells while examining its selectivity towards normal cells. Additionally, the study is directed to investigate cell death mechanisms, delineate modes of cell death, and explore intracellular ROS production. Cytotoxic effects of alcoholic, dichloromethane, and petroleum ether fractions of Dorema hyrcanum were investigated on cancer and normal cells by using MTT assay, and the concentration around IC50 values was used for flow cytometric assessment of apoptosis, evaluation of the expression of selected genes via RT-qPCR and production of ROS. Methanolic extract exhibited the highest cytotoxicity, impacting A2780CP and MDA-MB-231. All fractions showed comparable effects on U251 cells. Notably, extracts displayed higher IC50 values in normal HDF cells, indicating cancer cell specificity. Flow cytometry revealed induction of apoptosis and non-apoptotic death in all three cancer cell lines. QPCR results showed upregulation of related genes, with RIP3K prominently increased in U251 glioblastoma. The DCFH-DA assay demonstrated ROS induction by the PE fraction exclusively in A2780CP cells after 30 minutes and up to 24 hours. Dorema hyrcanum root extracts exhibited potent anti-tumor effects against all studied cell lines. The methanolic extract demonstrated the highest cytotoxicity, particularly against A2780CP and MDA-MB-231 cells. Importantly, all fractions displayed selectivity for cancer cells over normal HDF cells. Unique modes of action were observed, with the petroleum ether fraction inducing significant non-apoptotic cell death. These findings suggest promising therapeutic potential for Dorema hyrcanum in cancer treatment with subject to further mechanistic studies.

Anisomeles indica (L.) Kuntze leaf essential oil ameliorates LPS-induced inflammation in RAW 264.7 cells: An integrated approach of network pharmacology and experimental validation

Anisomeles indica (L.) Kuntze (Lamiaceae), commonly called catmint, is an essential oil-bearing herb used in traditional systems of medicine against rheumatism, convulsions, inflammatory skin disorders, and epilepsy. However, the efficacy and mechanism of action of its essential oil against inflammatory conditions remain elusive. The current study aims at the chemical characterization of the essential oil of A. indica leaves (AILEO) and understanding the mechanism of its anti-inflammatory effects by an integrated approach of network pharmacology and in vitro assays. GC–MS analysis of AILEO revealed a total of 30 constituents representing 94.19 % of the total oil. The majority of the chemical groups include diterpene hydrocarbons with abietatriene (58.13 %) and abietadiene (7.18 %) as the major constituents. Out of 30 compounds, 20 passed the ADME screening and were considered as active constituents. A total of 524 compound targets, 409 anti-inflammation targets, and 88 compound-disease intersecting targets were obtained. Multi-level network analysis revealed that the pharmacological mechanisms of alleviation of inflammation by AILEO are due to its interaction with five core inflammatory targets such as PI3K, AKT1, MEK1, ERK1, and RXRA involved in the PI3K-AKT signaling pathway. AILEO did not exhibit any cytotoxic effect on RAW 264.7 cells, but it significantly inhibited nitric oxide (NO) production and reduced the levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) in vitro assays. Further, AILEO enhanced the expression levels of endogenous antioxidant enzymes (CAT, SOD, GPx, and GSH) in comparison to the LPS-induced group. RT-qPCR analysis revealed that AILEO modulated the level of mRNA expression of all five core targets associated with the PI3K-AKT signaling pathway, which further supported the findings of network pharmacology. This study provides valuable insights into the intricate mechanisms by which AILEO exerts anti-inflammatory action indicating its pharmacological potential as a promising candidate for the treatment of disorders linked with inflammation.

Seven glycosides from the roots of Scrophularia ningpoensis

Three new glycosides (1–3) together with four known ones (4–7) were isolated from the roots of Scrophularia ningpoensis. Their structures were elucidated through extensive analysis of HR-ESI-MS, NMR, and ECD spectra. The anti-inflammatory potential of the new compounds was evaluated by measuring their ability to inhibit lipopolysaccharide (LPS) induced nitric oxide (NO) production in RAW 264.7 macrophage cells. In addition, the cytotoxic effects of the new compounds on HepG2, 4T1, and A549 cell lines were evaluated.

Tannic Acid Impedes the Proliferation of Bladder Cancer Cells by Elevating Mitochondrial Pathways of Apoptosis.

Bladder cancer stands as a prevailing neoplasm among men globally, distinguished for its pronounced malignancy attributed to invasiveness and metastatic proclivity. Tannic acid (TA), an organic compound in many plants, has garnered recent attention for its discernible anti-mutagenic attributes. This investigation endeavored to scrutinize the repercussions of TA on grade II bladder cancer, with a concerted focus on unraveling its anti-cancer mechanisms. The cytotoxic effects of TA on grade II bladder cancer cells were investigated using multiple techniques, including MTT assay, flow cytometry, TUNEL assay, and western blot. Our findings revealed that elevated concentrations of TA induced cytotoxic effects in grade II bladder cancer cells. Both flow cytometry and the TUNEL assay substantiated the dose-dependent capacity of TA to prompt apoptosis. Western blot analysis corroborated that TA treatment in bladder cancer cells resulted in the upregulation of cleaved caspase-3 expression and PARP. Furthermore, heightened TA dosage elicited an augmentation in the expression of pro-apoptotic proteins, namely Bax and Bak, alongside a reduction in the expression of the anti-apoptotic protein Bcl-2 within bladder cancer cells. This study confirms TA as a potential anticancer agent, demonstrably diminishing the viability of bladder cancer cells. TA exerts cytotoxicity through the activation of mitochondrial apoptotic pathways. Specifically, TA initiates the cleavage of PARP and caspase-3, concurrently augmenting the expression of pro-apoptotic proteins to facilitate apoptosis. Collectively, the present study indicates that TA effectively impedes the proliferation of bladder cancer cells by instigating apoptosis through the intrinsic mitochondrial pathway.

A three-dimensional cell culture approach to investigate cytotoxic effects and production of inflammatory mediators by epoxy resin-based and calcium silicate-based endodontic sealer.

The aim of the present study was to assess the cytocompatibility of epoxy resin-based AH Plus Jet (Dentsply De Trey, Konstanz, Germany), Sealer Plus (MK Life, Porto Alegre, Brazil), calcium silicate-based Bio-C Sealer (Angelus, Londrina, PR, Brazil), Sealer Plus BC (MK Life) and AH Plus BC (Dentsply) through a tridimensional (3D) culture model of human osteoblast-like cells. Spheroids of MG-63 cells were produced and exposed to fresh root canal sealers extracts by 24h, and the cytotoxicity was assessed by the Lactate Dehydrogenase assay (LDH). The distribution of dead cells within the microtissue was assessed by fluorescence microscopy, and morphological effects were investigated by histological analysis. The secreted inflammatory mediators were detected in cell supernatants through flow luminometry (XMap Luminex). Cells incubated with AH Plus Jet, AH Plus BC, Sealer Plus BC and Bio-C Sealer extracts showed high rates of cell viability, while the Sealer Plus induced a significant reduction of cell viability, causing reduction on the spheroid structure. Sealer Plus and Seaker Plus BC caused alterations on 3D microtissue morphology. The AH Plus BC extract was associated with the downregulation of secretion of pro-inflammatory cytokines IL-5, IL-7, IP-10 and RANTES. The new AH Plus BC calcium silicate-based endodontic sealer did not reduce cell viability in vitro, while led to the downregulation of pro-inflammatory cytokines. Choosing the appropriate endodontic sealer is a crucial step. AH Plus BC demonstrated high cell viability and downregulation of pro-inflammatory cytokines, appearing reliable for clinical use, while Sealer Plus presented lower cytocompatibility.

Nanoarchitectonics of an acetogenin-enriched nanosystem mediated by an aqueous extract of Annona cherimola Mill with anti-inflammatory and proapoptotic activity against HepG2 cell line

For the first time, this study shows the nanoarchitectonic process to obtain an acetogenin-enriched nanosystem (AuNPs-Ac) using an aqueous extract from Annona cherimola Mill (ACM) composed of gold nanoparticles embedded in an organic matrix that acts as stabilizing agent and presents anti-inflammatory activity and cytotoxical effect against HepG2 cell line, promoting apoptosis. The synthesis of AuNPs-Ac was confirmed by x-ray diffraction analysis, showing metallic gold as the only phase, and the scanning transmission microscope showed an organic cap covering the AuNPs-Ac. Fourier-transformed infrared suggests that the organic cap comprises a combination of different annonaceous acetogenins, alkaloids, and phenols by the presence of bands corresponding to aromatic rings and hydroxyl groups. High-Performance Liquid Chromatography has demonstrated the presence of annonacin, a potent acetogenin, in the extract of ACM. An in vitro anti-inflammatory activity of the extract of ACM and the AuNPs-Ac was performed using the albumin denaturation method, showing a nonlinear response, which is better than sodium diclofenac salt in a wide range of concentrations that goes from 200 to 400 μg ml−1 with both samples. The viability assay was studied using trypan blue, treating IMR90 and HepG2 at different concentrations of AuNPs-Ac. The results defined a median lethal dose of 800 μg ml−1 against HepG2 through apoptosis according to the ratio of caspase-cleaved 9/alpha-tubulin evaluated. It was also demonstrated that the nanosystem presents a higher cytotoxic effect on the HepG2 cell line than in IMR90, suggesting a targeted mechanism. In addition, the nanosystem performs better than using only the extract of ACM in the anti-inflammatory or antiproliferative test, attributed to their higher surface area.

Titanium dioxide nanoparticles enhance the detrimental effect of polystyrene nanoplastics on cell and plant physiology of Vicia lens (L.) Coss. & Germ. seedlings

Polystyrene nanoplastics and titanium dioxide nanoparticles are widely spread in all environments, often coexisting within identical frameworks. Both these contaminants can induce negative effects on cell and plant physiology, giving concerns on their possible interaction which could increase each other’s harmful effects on plants. Despite the urgency of this issue, there is very little literature addressing it. To evaluate the potential risk of this co-contamination, lentil seeds were treated for five days with polystyrene nanoplastics and titanium dioxide nanoparticles (anatase crystalline form), alone and in co-presence. Cytological analyses, and histochemical and biochemical evaluation of oxidative stress were carried out on isolated shoots and roots. TEM analysis seemed to indicate the absence of physical/chemical interactions between the two nanomaterials. Seedlings under cotreatment showed the greatest cytotoxic and genotoxic effects and high levels of oxidative stress markers associated with growth inhibition. Even if biochemical data did not evidence significant differences between materials treated with polystyrene nanoplastics alone or in co-presence with titanium dioxide nanoparticles, histochemical analysis highlighted a different pattern of oxidative markers, suggesting a synergistic effect by the two nanomaterials. In accordance, the fluorescence signal linked to nanoplastics in root and shoot was higher under cotreatment, perhaps due to the well-known ability of titanium dioxide nanoparticles to induce root tissue damage, in this way facilitating the uptake and translocation of polystyrene nanoplastics into the plant body. In the antioxidant machinery, peroxidase activity showed a significant increase in treated roots, in particular under cotreatment, probably more associated with stress-induced lignin synthesis than with hydrogen peroxide detoxification. Present results clearly indicate the worsening by metal nanoparticles of the negative effects of nanoplastics on plants, underlining the importance of research considering the impact of cotreatments with different nanomaterials, which may better reflect the complex environmental conditions.

Glutathione-responsive Aggregation-induced Emission Photosensitizers for Enhanced Photodynamic Therapy of Lung Cancer.

Lung cancer, a highly prevalent and lethal form of cancer, is often associated with oxidative stress. Photodynamic therapy (PDT) has emerged as a promising alternative therapeutic tool in cancer treatments, but its efficacy is closely correlated to the photosensitizers generating reactive oxygen species (ROS) and the antioxidant capacity of tumor cells. In particular, glutathione (GSH) can reduce the ROS and thus compromise PDT efficacy. In this study, a GSH-responsive near-infrared photosensitizer (TBPPN) based on aggregation-induced emission for real-time monitoring of GSH levels and enhanced PDT for lung cancer treatment is developed. The strategic design of TBPPN, consisting of a donor-acceptor structure and incorporation of dinitrobenzene, enables dual functionality by not only the fluorescence being activated by GSH but also depleting GSH to enhance the cytotoxic effect of PDT. TBPPN demonstrates synergistic PDT efficacy in vitro against A549 lung cancer cells by specifically targeting different cellular compartments and depleting intracellular GSH. In vivo studies further confirm that TBPPN can effectively inhibit tumor growth in a mouse model with lung cancer, highlighting its potential as an integrated agent for the diagnosis and treatment of lung cancer. This approach enhances the effectiveness of PDT for lung cancer and deserves further exploration of its potential for clinical application.

OrganoIDNet: a deep learning tool for identification of therapeutic effects in PDAC organoid-PBMC co-cultures from time-resolved imaging data.

Pancreatic Ductal Adenocarcinoma (PDAC) remains a challenging disease due to its complex biology and aggressive behavior with an urgent need for efficient therapeutic strategies. To assess therapy response, pre-clinical PDAC organoid-based models in combination with accurate real-time monitoring are required. We established stable live-imaging organoid/peripheral blood mononuclear cells (PBMCs) co-cultures and introduced OrganoIDNet, a deep-learning-based algorithm, capable of analyzing bright-field images of murine and human patient-derived PDAC organoids acquired with live-cell imaging. We investigated the response to the chemotherapy gemcitabine in PDAC organoids and the PD-L1 inhibitor Atezolizumab, cultured with or without HLA-matched PBMCs over time. Results obtained with OrganoIDNet were validated with the endpoint proliferation assay CellTiter-Glo. Live cell imaging in combination with OrganoIDNet accurately detected size-specific drug responses of organoids to gemcitabine over time, showing that large organoids were more prone to cytotoxic effects. This approach also allowed distinguishing between healthy and unhealthy status and measuring eccentricity as organoids' reaction to therapy. Furthermore, imaging of a new organoids/PBMCs sandwich-based co-culture enabled longitudinal analysis of organoid responses to Atezolizumab, showing an increased potency of PBMCs tumor-killing in an organoid-individual manner when Atezolizumab was added. Optimized PDAC organoid imaging analyzed by OrganoIDNet represents a platform capable of accurately detecting organoid responses to standard PDAC chemotherapy over time. Moreover, organoid/immune cell co-cultures allow monitoring of organoid responses to immunotherapy, offering dynamic insights into treatment behavior within a co-culture setting with PBMCs. This setup holds promise for real-time assessment of immunotherapeutic effects in individual patient-derived PDAC organoids.

Challenges of the Application of In Vitro Digestion for Nanomaterials Safety Assessment

Considering the increase in the production and use of nanomaterials (NM) in food/feed and food contact materials, novel strategies for efficient and sustainable hazard characterization, especially in the early stages of NM development, have been proposed. Some of these strategies encompass the utilization of in vitro simulated digestion prior to cytotoxic and genotoxic assessment. This entails exposing NM to fluids that replicate the three successive phases of digestion: oral, gastric, and intestinal. Subsequently, the resulting digestion products are added to models of intestinal cells to conduct toxicological assays, analyzing multiple endpoints. Nonetheless, exposure of intestinal cells to the digested products may induce cytotoxicity effects, thereby posing a challenge to this strategy. The aim of this work was to describe the challenges encountered with the in vitro digestion INFOGEST 2.0 protocol when using the digestion product in toxicological studies of NM, and the adjustments implemented to enable its use in subsequent in vitro biological assays with intestinal cell models. The adaptation of the digestion fluids, in particular the reduction of the final bile concentration, resulted in a reduced toxic impact of digestion products.

Novel quinoxaline analogs as telomeric G-quadruplex ligands exert antitumor effects related to enhanced immunomodulation

G-quadruplexes (G4s) are commonly formed in the G-rich strand of telomeric DNA. Ligands targeting telomeric G4 induce DNA damage and telomere dysfunction, which makes them potential antitumor drugs. New telomeric G4 ligands with drug-likeness are still needed to be exploited, especially with their antitumor mechanisms thoroughly discussed. In this study, a novel series of quinoxaline analogs were rationally designed and synthesized. Among them, R1 was the most promising ligand for its cytotoxic effects on tumor cells and stabilizing ability with telomeric G4. Cellular assays illustrated that R1 stabilized G4 and induced R-loop accumulation in the telomeric regions, subsequently triggering DNA damage responses, cell cycle arrest in G2/M phase, apoptosis and antiproliferation. Moreover, R1 evoked immunogenic cell death (ICD) in tumor cells, which promoted the maturation of bone marrow derived dendritic cells (BMDCs). In breast cancer mouse model, R1 exhibited a significant decrease in tumor burden through the immunomodulatory effects, including the increase of CD4+ and CD8+ T cells in tumors and cytokine levels in sera. Our research provides a new idea that targeting telomeric G4 induces DNA damage responses, causing antitumor effects both in vitro and in vivo, partially due to the enhancement of immunomodulation.

Examination of cytotoxic and antimicrobial effect of whitening toothpastes: an in vitro study.

Toothpastes are widely used to protect oral and teeth health. This study aims to examine the cytotoxic and antimicrobial effects of whitening toothpastes. In this study, extracts were prepared according to ISO 10993-12:2021 standard (0.2 g/mL) using whitening and conventional toothpastes. The prepared extracts were added to human gingival fibroblast cell lines (HGF-1) in different dilutions (1:1, 1:2, 1:4, 1:8, 1:16, and 1:32) and a cytotoxicity test was performed. Antimicrobial analysis of toothpastes was performed on Streptococcus mutans, Staphylococcus aureus, and Candida albicans using the hole-plate diffusion method. Cell viability and microbial analysis data were examined using two-way analysis of variance (ANOVA) and Tukey post-hoc test (p < 0.05). Toothpastes with sodium lauryl sulfate (SLS) in their composition showed statistically more toxic effects (p < 0.05). The activated carbon toothpastes without SLS showed over 90% cell viability after dilution. Although the dilution rate of toothpastes containing SLS increased, cell viability remained below 70%. All toothpastes used in the study showed antimicrobial effects on S. mutans, S. aureus, and C. albicans. Toothpaste containing hydrogen peroxide and SLS produced more antibacterial effects than activated carbon, blue covarine, microparticles, and conventional toothpaste. SLS-containing toothpastes showed more toxicity on HGF-1 cells. Toothpaste containing hydroxyapatite did not show toxic effects on HGF-1 cells. SLS, sodium lauryl sarcosinate and hydrogen peroxide in toothpastes increase antimicrobial effects.

Megakaryocytic IGF1 coordinates activation and ferroptosis to safeguard hematopoietic stem cell regeneration after radiation injury.

Hematopoietic stem cell (HSC) regeneration underlies hematopoietic recovery from myelosuppression, which is a life-threatening side effect of cytotoxicity. HSC niche is profoundly disrupted after myelosuppressive injury, while if and how the niche is reshaped and regulates HSC regeneration are poorly understood. A mouse model of radiation injury-induced myelosuppression was built by exposing mice to a sublethal dose of ionizing radiation. The dynamic changes in the number, distribution and functionality of HSCs and megakaryocytes were determined by flow cytometry, immunofluorescence, colony assay and bone marrow transplantation, in combination with transcriptomic analysis. The communication between HSCs and megakaryocytes was determined using a coculture system and adoptive transfer. The signaling mechanism was investigated both in vivo and in vitro, and was consolidated using megakaryocyte-specific knockout mice and transgenic mice. Megakaryocytes become a predominant component of HSC niche and localize closer to HSCs after radiation injury. Meanwhile, transient insulin-like growth factor 1 (IGF1) hypersecretion is predominantly provoked in megakaryocytes after radiation injury, whereas HSCs regenerate paralleling megakaryocytic IGF1 hypersecretion. Mechanistically, HSCs are particularly susceptible to megakaryocytic IGF1 hypersecretion, and mTOR downstream of IGF1 signaling not only promotes activation including proliferation and mitochondrial oxidative metabolism of HSCs, but also inhibits ferritinophagy to restrict HSC ferroptosis. Consequently, the delicate coordination between proliferation, mitochondrial oxidative metabolism and ferroptosis ensures functional HSC expansion after radiation injury. Importantly, punctual IGF1 administration simultaneously promotes HSC regeneration and hematopoietic recovery after radiation injury, representing a superior therapeutic approach for myelosuppression. Our study identifies megakaryocytes as a last line of defense against myelosuppressive injury and megakaryocytic IGF1 as a novel niche signal safeguarding HSC regeneration.

Extracellular vesicles containing MFGE8 from colorectal cancer facilitate macrophage efferocytosis

BackgroundColorectal cancer (CRC) commonly exhibits tolerance to cisplatin treatment, but the underlying mechanisms remain unclear. Within the tumor microenvironment, macrophages play a role in resisting the cytotoxic effects of chemotherapy by engaging in efferocytosis to clear apoptotic cells induced by chemotherapeutic agents. The involvement of extracellular vesicles (EVs), an intercellular communicator within the tumor microenvironment, in regulating the efferocytosis for the promotion of drug resistance has not been thoroughly investigated.MethodsWe constructed GFP fluorescent-expressing CRC cell lines (including GFP-CT26 and GFP-MC38) to detect macrophage efferocytosis through flow cytometric analysis. We isolated and purified CRC-secreted EVs using a multi-step ultracentrifugation method and identified them through electron microscopy and nanoflow cytometry. Proteomic analysis was conducted to identify the protein molecules carried by CRC-EVs. MFGE8 knockout CRC cell lines were constructed using CRISPR-Cas9, and their effects were validated through in vitro and in vivo experiments using Western blotting, immunofluorescence, and flow cytometric analysis, confirming that these EVs activate the macrophage αvβ3-Src-FAK-STAT3 signaling pathway, thereby promoting efferocytosis.ResultsIn this study, we found that CRC-derived EVs (CRC-EVs) enhanced macrophage efferocytosis of cisplatin-induced apoptotic CRC cells. Analysis of The Cancer Genome Atlas (TCGA) database revealed a high expression of the efferocytosis-associated gene MFGE8 in CRC patients, suggesting a poorer prognosis. Additionally, mass spectrometry-based proteomic analysis identified a high abundance of MFGE8 protein in CRC-EVs. Utilizing CRISPR-Cas9 gene edition system, we generated MFGE8-knockout CRC cells, demonstrating that their EVs fail to upregulate macrophage efferocytosis in vitro and in vivo. Furthermore, we demonstrated that MFGE8 in CRC-EVs stimulated macrophage efferocytosis by increasing the expression of αvβ3 on the cell surface, thereby activating the intracellular Src-FAK-STAT3 signaling pathway.ConclusionsTherefore, this study highlighted a mechanism in CRC-EVs carrying MFGE8 activated the macrophage efferocytosis. This activation promoted the clearance of cisplatin-induced apoptotic CRC cells, contributing to CRC resistance against cisplatin. These findings provide novel insights into the potential synergistic application of chemotherapy drugs, EVs inhibitors, and efferocytosis antagonists for CRC treatment.