Real time monitoring and quantification of reactive oxygen species in breast cancer cell line MCF-7 by 2′,7′–dichlorofluorescin diacetate (DCFDA) assay

ROS-mediated anticancer effects of EGFR-targeted nanoceria

The therapeutic effectiveness of anticancer drugs, including nanomedicines, can be enhanced with active receptor-targeting strategies. Epidermal growth factor receptor (EGFR) is an important cancer biomarker, constitutively expressed in sarcoma patients of different histological types. The present work reports materials and in vitro biomedical analyses of silanized (passive delivery) and/or EGF-functionalized (active delivery) ceria nanorods exhibiting highly defective catalytically active surfaces. The EGFR-targeting efficiency of nanoceria was confirmed by receptor-binding studies. Increased cytotoxicity and reactive oxygen species (ROS) production were observed for EGF-functionalized nanoceria owing to enhanced cellular uptake by HT-1080 fibrosarcoma cells. The uptake was confirmed by TEM and confocal microscopy. Silanized nanoceria demonstrated negligible/minimal cytotoxicity toward healthy MRC-5 cells at 24 and 48 h, whereas this was significant at 72 h owing to a nanoceria accumulation effect. In contrast, considerable cytotoxicity toward the cancer cells was exhibited at all three times points. The ROS generation and associated cytotoxicity were moderated by the equilibrium between catalysis by ceria, generation of cell debris, and blockage of active sites. EGFR-targeting is shown to enhance the uptake levels of nanoceria by cancer cells, subsequently enhancing the overall anticancer activity and therapeutic performance of ceria.

Environmental Chemical-Induced Reactive Oxygen Species Generation and Immunotoxicity: A Comprehensive Review

Significance: Reactive oxygen species (ROS), the reactive oxygen-carrying chemicals moieties, act as pleiotropic signal transducers to maintain various biological processes/functions, including immune response. Increased ROS production leads to oxidative stress, which is implicated in xenobiotic-induced adverse effects. Understanding the immunoregulatory mechanisms and immunotoxicity is of interest to developing therapeutics against xenobiotic insults. Recent Advances: While developmental studies have established the essential roles of ROS in the establishment and proper functioning of the immune system, toxicological studies have demonstrated high ROS generation as one of the potential mechanisms of immunotoxicity induced by environmental chemicals, including heavy metals, pesticides, aromatic hydrocarbons (benzene and derivatives), plastics, and nanoparticles. Mitochondrial electron transport and various signaling components, including NADH oxidase, toll-like receptors (TLRs), NF-κB, JNK, NRF2, p53, and STAT3, are involved in xenobiotic-induced ROS generation and immunotoxicity. Critical Issues: With many studies demonstrating the role of ROS and oxidative stress in xenobiotic-induced immunotoxicity, rigorous and orthogonal approaches are needed to achieve in-depth and precise understanding. The association of xenobiotic-induced immunotoxicity with disease susceptibility and progression needs more data acquisition. Furthermore, the general methodology needs to be possibly replaced with high-throughput precise techniques. Future Directions: The progression of xenobiotic-induced immunotoxicity into disease manifestation is not well documented. Immunotoxicological studies about the combination of xenobiotics, age-related sensitivity, and their involvement in human disease incidence and pathogenesis are warranted. Antioxid. Redox Signal. 40, 691-714.

A carrier-free tri-component nanoreactor for multi-pronged synergistic cancer therapy

Non-invasive therapies such as photodynamic therapy (PDT) and chemodynamic therapy (CDT) have received wide attention due to their low toxicity and side effects, but their efficacy is limited by the tumor microenvironment (TME), and monotherapy cannot achieve satisfactory efficacy. In this work, a multifunctional nanoparticle co-assembled from oleanolic acid (OA), chlorin e6 (Ce6) and hemin was developed. The as-constructed nanoparticle named OCH with diameters of around 130 nm possessed good biostability, pH/GSH dual-responsive drug release properties, and remarkable cellular internalization and tumor accumulation capabilities. OCH exhibited prominent catalytic activities to generate •OH, deplete GSH, and produce O2 to overcome the hypoxia TME, thus potentiating the photodynamic and chemodynamic effect. In addition, OCH can induce the occurrence of ferroptosis in both ferroptosis-sensitive and ferroptosis-resistant cancer cells. The multi-pronged effects of OCH including hypoxia alleviation, GSH depletion, ferroptosis induction, CDT and PDT effects jointly facilitate excellent anticancer effects in vitro and in vivo. Hence, this work will advance the development of safe and effective clinically transformable nanomedicine by employing clinically-applied agents to form drug combinations for efficient multi-pronged combination cancer therapy.

ON/OFF based synergetic plasmonic photothermal drug release approach through core-satellite like mussel-inspired polydopamine nanoparticles

One of the studies on new drug delivery and release systems that has increased in recent years is the study using plasmonic nanoparticles. In this study, polydopamine nanoparticles (PDOP NPs), which contribute to photothermal drug release by near infrared radiation (NIR), were decorated with gold nanoparticles (AuNPs) to utilize their plasmonic properties, and a core-satellite-like system was formed. With this approach, epirubicin (EPI)-loaded PDOP NPs were prepared by utilizing the plasmonic properties of AuNPs. Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction (XRD) methods were used to evaluate the structural properties of these particles. The release behavior of the prepared structures in acidic (pH 5.0) and neutral (pH 7.4) environments based on the ON/OFF approach was also examined. The biocompatibility properties of the particles were evaluated on mouse fibroblast (L929) and anticancer activities on neuroblastoma (SH-SY5Y) cells. The effects of prepared EPI-loaded particles and laser-controlled drug release on ROS production, genotoxicity, and apoptosis were also investigated in SH-SY5Y cells. With the calculated combination index (CI) value, it was shown that the activity of EPI-loaded AuNP@PDOP NPs increased synergistically with the ON/OFF-based approach. The developed combination approach is considered to be remarkable and promising for further evaluation before clinical use.

Targeted delivery and apoptosis induction of CDK-4/6 inhibitor loaded folic acid decorated lipid-polymer hybrid nanoparticles in breast cancer cells

Targeted drug delivery is an advanced approach for active targeting of tumor that can enhance the concentration of the drug at the site of action and reduce the off-target toxicity and non-specific effects of the drug. Folate receptors (FR) are membrane-bound surface proteins, over-expressed in numerous solid tumors, folate and folate conjugates bind to FR with higher affinity. In the present investigation, we fabricated Folic acid (FA) decorated Palbociclib loaded lipid-polymer hybrid nanoparticles (FA-PLPHNPs) using quality by design (QbD) approach and evaluated its anti-cancer activity in folate receptor-positive breast cancer cell lines. 1HNMR, ATR-FTIR spectroscopic techniques confirmed the formation of DSPE-PEG-FA ligand. The optimized FA-PLPHNPs formulation exhibited 143.36 ± 5.24 nm, 0.172 ± 0.004, -16.84 ± 0.27 mV, and 93.12 ± 0.43 % of particle size, PDI, zeta potential and % entrapment efficiency, respectively. The FA-PLPHNPs exhibited an approximately 9, 11-fold reduction in IC50 values than free Palbociclib in MCF-7 and MDA-MB-231 cells at 48 h. The role of FA in targeting breast cancer was studied by means of a receptor-blocking assay, and concluded that FA-PLPHNPs were internalized into MCF-7 and MDA-MB-231 cells by folate receptor-mediated endocytosis. FA-PLPHNPs showed higher anti-cancer efficiency and caused enhanced reactive oxygen species generation, apoptosis (Acridine orange/ ethidium bromide dual staining and Annexin V/PI staining), reduced cell migration, and colony formation. Thus, the fabricated Palbociclib-loaded FA-conjugated lipid polymer hybrid nanoparticles could act as a potential nanocarrier for the treatment of breast cancer.

Breast cancer cells are sensitized by piperine to radiotherapy through estrogen receptor-α mediated modulation of a key NHEJ repair protein- DNA-PK

BACKGROUND

Non-homologous end joining, an important DNA-double-stranded break repair pathway, plays a prominent role in conferring resistance to radiotherapeutic agents, resulting in cancer progression and relapse.

PURPOSE

The molecular players involved in the radio-sensitizing effects of piperine and many other phytocompounds remain evasive to a great extent. The study is designed to assess if piperine, a plant alkaloid can alter the radioresistance by modulating the expression of non-homologous end-joining machinery.

METHODS AND MATERIALS

Estrogen receptor-positive/negative, breast cancer cells were cultured to understand the synergetic effects of piperine with radiotherapy. Cisplatin and Bazedoxifene were used as positive controls. Cells were exposed to γ- radiation using Low Dose gamma Irradiator-2000. The piperine effect on Estrogen receptor modulation, DNA-Damage, DNA-Damage-Response, and apoptosis was done by western blotting, immunofluorescence, yeast-based-estrogen-receptor-LacZ-reporter assay, and nuclear translocation analysis. Micronuclei assay was done for DNA damage and genotoxicity, and DSBs were quantified by γH2AX-foci-staining using confocal microscopy. Flow cytometry analysis was done to determine the cell cycle, mitochondrial membrane depolarization, and Reactive oxygen species generation. Pharmacophore analysis and protein-ligand interaction studies were done using Schrodinger software. Synergy was computed by compusyn-statistical analysis. Standard errors/deviation/significance were computed with GraphPad prism.

RESULTS

Using piperine, we propose a new strategy for overcoming acquired radioresistance through estrogen receptor-mediated modulation of the NHEJ pathway. This is the first comprehensive study elucidating the mechanism of radio sensitizing potential of piperine. Piperine enhanced the radiation-induced cell death and enhanced the expression and activation of Estrogen receptor β, while Estrogen receptor α expression and activation were reduced. In addition, piperine shares common pharmacophore features with most of the known estrogen agonists and antagonists. It altered the estrogen receptor α/β ratio and the expression of estrogen-responsive proteins of DDR and NHEJ pathway. Enhanced expression of DDR proteins, ATM, p53, and P-p53 with low DNA-PK repair complex (comprising of DNA-PKcs/Ku70/Ku80), resulted in the accumulation of radiation-induced DNA double-stranded breaks (as evidenced by MNi and γH2AX-foci) culminating in cell cycle arrest and mitochondrial-pathway of apoptosis.

CONCLUSION

In conclusion, our study for the first time reported that piperine sensitizes breast cancer cells to radiation by accumulating DNA breaks, through altering the expression of DNA-PK Complex, and DDR proteins, via selective estrogen receptor modulation, offering a novel strategy for combating radioresistance.

Quantum Sensing of Free Radicals in Primary Human Granulosa Cells with Nanoscale Resolution

Cumulus granulosa cells (cGCs) and mural granulosa cells (mGCs), although derived from the same precursors, are anatomically and functionally heterogeneous. They are critical for female fertility by supporting oocyte competence and follicular development. There are various techniques used to investigate the role of free radicals in mGCs and cCGs. Yet, temporospatial resolution remains a challenge. We used a quantum sensing approach to study free radical generation at nanoscale in cGCs and mGCs isolated from women undergoing oocyte retrieval during in vitro fertilization (IVF). Cells were incubated with bare fluorescent nanodiamonds (FNDs) or mitochondria targeted FNDs to detect free radicals in the cytoplasm and mitochondria. After inducing oxidative stress with menadione, we continued to detect free radical generation for 30 min. We observed an increase in free radical generation in cGCs and mGCs from 10 min on. Although cytoplasmic and mitochondrial free radical levels are indistinguishable in the physiological state in both cGCs and mGCs, the free radical changes measured in mitochondria were significantly larger in both cell types, suggesting mitochondria are sites of free radical generation. Furthermore, we observed later occurrence and a smaller percentage of cytoplasmic free radical change in cGCs, indicating that cGCs may be more resistant to oxidative stress.

Attenuation of Dopaminergic Neurodegeneration in a C. elegans Parkinson's Model through Regulation of Xanthine Dehydrogenase (XDH-1) Expression by the RNA Editase, ADR-2

Differential RNA editing by adenosine deaminases that act on RNA (ADARs) has been implicated in several neurological disorders, including Parkinson's disease (PD). Here, we report results of a RNAi screen of genes differentially regulated in adr-2 mutants, normally encoding the only catalytically active ADAR in Caenorhabditis elegans, ADR-2. Subsequent analysis of candidate genes that alter the misfolding of human α-synuclein (α-syn) and dopaminergic neurodegeneration, two PD pathologies, reveal that reduced expression of xdh-1, the ortholog of human xanthine dehydrogenase (XDH), is protective against α-synuclein-induced dopaminergic neurodegeneration. Further, RNAi experiments show that WHT-2, the worm ortholog of the human ABCG2 transporter and a predicted interactor of XDH-1, is the rate-limiting factor in the ADR-2, XDH-1, WHT-2 system for dopaminergic neuroprotection. In silico structural modeling of WHT-2 indicates that the editing of one nucleotide in the wht-2 mRNA leads to the substitution of threonine with alanine at residue 124 in the WHT-2 protein, changing hydrogen bonds in this region. Thus, we propose a model where wht-2 is edited by ADR-2, which promotes optimal export of uric acid, a known substrate of WHT-2 and a product of XDH-1 activity. In the absence of editing, uric acid export is limited, provoking a reduction in xdh-1 transcription to limit uric acid production and maintain cellular homeostasis. As a result, elevation of uric acid is protective against dopaminergic neuronal cell death. In turn, increased levels of uric acid are associated with a decrease in ROS production. Further, downregulation of xdh-1 is protective against PD pathologies because decreased levels of XDH-1 correlate to a concomitant reduction in xanthine oxidase (XO), the form of the protein whose by-product is superoxide anion. These data indicate that modifying specific targets of RNA editing may represent a promising therapeutic strategy for PD.

Iron-silicate-coated porous silicon nanoparticles for in situ ROS self-generation

Porous silicon nanoparticles (pSiNPs) have gained attention from drug delivery systems (DDS) due to their biocompatibility, high drug-loading efficiency, and facile surface modification. To date, many surface chemistries of pSiNPs have been developed to maximize the merits and overcome the drawbacks of pSiNPs. In this work, we newly disclosed a formulation, iron-silicate-coated pSiNPs (Fe-pSiNPs-NCS), using the surface modification method with iron-silicate and 3-isothiocyanatopropyltriethoxysilane (TEPITC). Fe-pSiNPs-NCS demonstrated effective reactive-oxygen species (ROS) self-generation ability via a Fenton-like reaction of iron-silicate and in situ hydrogen peroxide (H₂O₂) generation of TEPITC on the surface of pSiNPs, resulting in excellent anticancer effect in U87MG cancer cells. Moreover, we confirmed that Fe-pSiNPs-NCS could be used as a drug delivery carrier as it was proven that anticancer drugs (doxorubicin, SN-38) were loaded into Fe-pSiNPs-NCS with high-loading efficiency. These findings could offer efficient strategies for developing nanotherapeutics in biomedical fields.

Bread melanoidins as potential new sustainable bakery ingredients: a study using fat and fat-free bakery food models

Melanoidins isolated from bakery by-products are proposed as new sustainable ingredients for bakery products. The colour, odour profile, texture, water activity, and antioxidant capacity of two bakery food models, fat and fat-free, enriched with 2% and 4% soft bread and common bread melanoidins, were analysed. The colour of the bakery food models with melanoidins was darker than that of the respective control; the fat-free models with melanoidins showed higher values of hardness than the control, while no significant effect was observed in the fat models; the water activity did not change compared to the control; the odour profile was significantly modified with different effects depending on the type of melanoidin quantity added and the food model (fat or fat-free); and the antioxidant capacity increased proportionally to the quantity of melanoidin added. In general, melanoidins from soft bread exhibited a higher effect than the melanoidins from common bread. The melanoidins isolated from both fat and fat-free bakery food models did not show cytotoxicity nor did they modify the levels of reactive oxygen species in Caco-2 cells. Therefore, the results seem to indicate the favourable potential of bread melanoidins as new sustainable ingredients for bakery products.

Oxidative Stress-Induced Silver Nano-Carriers for Chemotherapy

Recently, silver nanoparticles (AgNPs) have been extensively explored in a variety of biological applications, especially cancer treatment. AgNPs have been demonstrated to exhibit anti-tumor effects through cell apoptosis. This study intends to promote cell apoptosis further by increasing oxidative stress. AgNPs are encapsulated by biocompatible and biodegradable polyaspartamide (PA) (PA-AgNPs) that carries the anti-cancer drug Doxorubicin (Dox) to inhibit cancer cells primarily. PA-AgNPs have an average hydrodynamic diameter of 130 nm, allowing them to move flexibly within the body. PA-AgNPs show an excellent targeting capacity to cancer cells when they are conjugated to biotin. In addition, they release Dox efficiently by up to 88% in cancer environments. The DCFDA experiment demonstrates that the Dox-carried PA-AgNPs generate reactive oxidation species intensively beside 4T1 cells. The MTT experiment confirms that PA-AgNPs with Dox may strongly inhibit 4T1 cancer cells. Furthermore, the in vivo study confirms that PA-AgNPs with Dox successfully inhibit tumors, which are about four times smaller than the control group and have high biosafety that can be applied for chemotherapy.

Enhanced Antioxidant Effects of Naringenin Nanoparticles Synthesized using the High-Energy Ball Milling Method

Naringenin, one of the flavonoid components, is majorly found in and obtained from grapefruits and oranges. Naringenin also acts as a potent antioxidant, which possesses hypolipidemic as well as anti-inflammatory potential. Naringenin reduces the expressions of several inflammatory mediators, viz., NF-κB, cycloxygenase-2, and other cytokine mediators. In spite of having various biological effects, the clinical application of naringenin is restricted due to its very poor aqueous solubility. In the present study, the high-energy ball milling method was employed for the preparation of naringenin nanoparticles without using any chemical with an aim to enhance the anti-oxidant potential of naringenin. The milled naringenin nanoparticles were characterized for their physicochemical properties using scanning electron microscopy (SEM) and X-ray diffraction. Additionally, the effects of milling time and temperature were further assessed on the solubility of crude and milled naringenin samples. The antioxidant potential of milled naringenin was evaluated with various assays such as DHE, DCFDA, and cleaved caspase-3 using SH-SY5Y human neuroblastoma cells. The nanoparticle size of naringenin after milling was confirmed using SEM analysis. Crystalline peaks for milled and crude samples of naringenin also established that both the naringenin forms were in the crystalline form. The solubility of naringenin was enhanced depending on the milling time and temperature. Moreover, crude and milled naringenin were found to be cytocompatible up to doses of 120 μM each for the duration of 24 and 48 h. It was also observed that milled naringenin at the doses of 1, 2, and 5 μM significantly reduced the levels of reactive oxygen species (ROS) generated by H₂O₂ and exhibited superior ROS scavenging effects as compared to those of crude or un-milled forms of naringenin. Furthermore, milled naringenin at the doses of 1 and 2 μM inhibited H₂O₂-induced cell death, as shown by immunofluorescence staining of cleaved caspase-3 and Annexin-V PI flow cytometry analysis. Conclusively, it could be suggested that the size reduction of naringenin using high-energy ball milling techniques substantially enhanced the antioxidant potential as compared to naïve or crude naringenin, which may be attributed to its enhanced solubility due to reduced size.

Experimental Conditions That Influence the Utility of 2′7′-Dichlorodihydrofluorescein Diacetate (DCFH2-DA) as a Fluorogenic Biosensor for Mitochondrial Redox Status

Oxidative stress has been causally linked to various diseases. Electron transport chain (ETC) inhibitors such as rotenone and antimycin A are frequently used in model systems to study oxidative stress. Oxidative stress that is provoked by ETC inhibitors can be visualized using the fluorogenic probe 2′,7′-dichlorodihydrofluorescein-diacetate (DCFH₂-DA). Non-fluorescent DCFH₂-DA crosses the plasma membrane, is deacetylated to 2′,7′-dichlorodihydrofluorescein (DCFH₂) by esterases, and is oxidized to its fluorescent form 2′,7′-dichlorofluorescein (DCF) by intracellular ROS. DCF fluorescence can, therefore, be used as a semi-quantitative measure of general oxidative stress. However, the use of DCFH₂-DA is complicated by various protocol-related factors that mediate DCFH₂-to-DCF conversion independently of the degree of oxidative stress. This study therefore analyzed the influence of ancillary factors on DCF formation in the context of ETC inhibitors. It was found that ETC inhibitors trigger DCF formation in cell-free experiments when they are co-dissolved with DCFH₂-DA. Moreover, the extent of DCF formation depended on the type of culture medium that was used, the pH of the assay system, the presence of fetal calf serum, and the final DCFH₂-DA solvent concentration. Conclusively, experiments with DCFH₂-DA should not discount the influence of protocol-related factors such as medium and mitochondrial inhibitors (and possibly other compounds) on the DCFH₂-DA-DCF reaction and proper controls should always be built into the assay protocol.

Combinatorial delivery of Ribociclib and Green tea extract mediated nanostructured lipid carrier for oral delivery for the treatment of breast cancer synchronizing in silico, in vitro, and in vivo studies

Purpose: The current research investigated the development and evaluation of dual drug-loaded nanostructure lipidic carriers (NLCs) of green tea extract and Ribociclib.Method: In silico study were performed to determine the effectiveness of combinational approach. The prepared NLCs were subjected to in vitro drug release, lipolysis, haemolysis and cell line studies to assess their in vivo prospect.Results: In silico study was done to get docking score of EGCG (-8.98) close to Ribociclib (-10.78) in CDK-4 receptors. The prepared NLCs exhibited particle size (175.80 ± 3.51 nm); PDI (0.571 ± 0.012); and %EE [RBO (80.91 ± 1.66%) and GTE 75.98 ± 2.35%)] respectively. MCF-7 cell lines were used to evaluate the MTT assay, cellular uptake and antioxidant (ROS and SOD) of prepared NLCs. In vitro drug release showed the controlled release up to 72 h. In vitro lipolysis and in vitro haemolysis studies showed the availability of drugs at absorption sites and the greater in vivo prospects of NLCs respectively. Pharmacokinetic study revealed a 3.63-fold and 1.53-fold increment in RBO and GTE bioavailability in female Wistar rats respectively.Conclusion: The prominent potential of green tea extract and RBO-loaded NLCs in enhancing their therapeutic efficacy for better treatment of breast cancer.

The dimerization of methyl vanillate improves its effect against breast cancer cells via pro-oxidant effect

Phenolic phytochemicals are a group of organic compounds with potent antioxidant features but can also act as powerful pro-oxidants. These characteristics are effective in reducing metastatic potential in cancer cells, and this effect has been associated with reactive oxygen species (ROS). Methyl vanillate (MV) and its dimer, methyl divanillate (DMV), are potent antioxidants. In the present study, we investigated the effects of MV and DMV on breast cancer cell lines MCF-7 and MDA-MB-231 and compared the results using the non-tumor cell line HB4a. Our results indicated that the compounds performed a pro-oxidant action, increasing the generation of ROS. DMV decreased the viability cell, showing a higher apoptotic effect and inhibition of proliferation than MV on both cell lines, with significant differences between groups (p < 0.05). Some modulation of NOX4, NOX5, and DUOX were observed, but the results did not correlate with the intracellular production of ROS. The dimer showed more effectivity and pro-oxidant effect than MV, impacting cell line MCF-7 in higher extension than MDA-MB-231. In conclusion, and corroborating with reported works, the dimerization of natural phenolic compounds was associated with improved beneficial biological effects as a potential cytotoxic agent to tumor cells.

Oxaliplatin delivery via chitosan/vitamin E conjugate micelles for improved efficacy and MDR-reversal in breast cancer

A bioinspired chitosan/vitamin E conjugate (Ch/VES, 1:4) was synthesized, optimized based on chitosan's molecular weight (15, 300 kDa), and was assembled to entrap oxaliplatin (OXPt). 1H NMR, infrared spectroscopy, chromatography, X-ray photoelectron spectroscopy, X-ray diffraction, drug release, hemolysis, and stability studies were performed to characterize OXPt@Ch/VES micelles. The therapeutic efficacy of the micelles was tested in vitro in ER+/PR+/HER2- and triple-negative sensitive/resistant breast cancer cells, MCF-7 and MDA-MB-231 via cellular uptake, cytotoxicity, nuclear staining, DNA fragmentation, mitochondrial membrane potential, ROS generation, apoptosis, and cell cycle assays and in vivo using 4T1(Luc)-tumor-bearing mice. OXPt@Ch/VES Ms exhibited decreased IC50 towards MCF-7, MDA-MB-231 (sensitive/resistant) than OXPt. OXPt@Ch/VES Ms caused extensive DNA damage, mitochondrial depolarization, apoptosis, and cell-growth arrest (G2/M). OXPt@Ch/VES Ms treatment retarded tumor growth significantly, prolonged survival, and decreased nephrotoxicity than OXPt. The OXPt@Ch/VES Ms could serve as a potential nanomedicine to overcome conventional OXPt-mediated drug resistance/nephrotoxicity in breast cancer.

Components of Banisteriopsis caapi, a Plant Used in the Preparation of the Psychoactive Ayahuasca, Induce Anti-Inflammatory Effects in Microglial Cells

Banisteriopsis caapi is used to prepare the psychoactive beverage ayahuasca, and both have therapeutic potential for the treatment of many central nervous system (CNS) conditions. This study aimed to isolate new bioactive compounds from B. caapi extract and evaluate their biological activity, and that of the known β-carboline components of the plant (harmine, harmaline, and tetrahydroharmine), in BV-2 microglial cells, the in vivo activation of which is implicated in the physiopathology of CNS disorders. B. caapi extract was fractionated using semipreparative liquid chromatography (HPLC-DAD) and the exact masses ([M + H]⁺m/z) of the compounds in the 5 isolated fractions were determined by high-resolution LC-MS/MS: F1 (174.0918 and 233.1289), F2 (353.1722), F3 (304.3001), F4 (188.1081), and F5 (205.0785). Harmine (75.5–302 µM) significantly decreased cell viability after 2 h of treatment and increased the number of necrotic cells and production of reactive oxygen species at equal or lower concentrations after 24 h. F4 did not impact viability but was also cytotoxic after 24 h. Most treatments reduced proinflammatory cytokine production (IL-2, IL-6, IL-17, and/or TNF), especially harmaline and F5 at 2.5 µM and higher concentrations, tetrahydroharmine (9.3 µM and higher), and F5 (10.7 µM and higher). The results suggest that the compounds found in B. caapi extract have anti-inflammatory potential that could be explored for the development of treatments for neurodegenerative diseases.

Effects of Bismuth Oxide Nanoparticles, Cisplatin and Baicalein-rich Fraction on ROS Generation in Proton Beam irradiated Human Colon Carcinoma Cells

Introduction: Proton beam radiotherapy is an advanced cancer treatment technique, which would reduce the effects of radiation on the surrounding healthy cells. The usage of radiosensitizers in this technique might further elevate the radiation dose towards the cancer cells.

Material and methods: The present study investigated the production of intracellular reactive oxygen species (ROS) due to the presence of individual radiosensitizers, such as bismuth oxide nanoparticles (BiONPs), cisplatin (Cis) or baicalein-rich fraction (BRF) from Oroxylum indicum plant, as well as their combinations, such as BiONPs-Cis (BC), BiONPs-BRF (BB), or BiONPs-Cis-BRF (BCB), on HCT-116 colon cancer cells under proton beam radiotherapy.

Results: It was found that the ROS in the presence of Cis at 3 Gy of radiation dose was the highest, followed by BC, BiONPs, BB, BRF, and BCB treatments. The properties of bismuth as a radical scavenger, as well as the BRF as a natural compound, might contribute to the lower intracellular ROS induction. The ROS in the presence of Cis and BC combination were also time-dependent and radiation dose-dependent.

Conclusions: As the prospective alternatives to the Cis, the BC combination and individual BiONPs showed the capacities to be developed as radiosensitizers for proton beam therapy.

A nanosensitizer self-assembled from oleanolic acid and chlorin e6 for synergistic chemo/sono-photodynamic cancer therapy

BACKGROUND

Sono-photodynamic therapy (SPDT) which is the combination of photodynamic therapy (PDT) and sonodynamic therapy (SDT), could exert much better anti-cancer effects than monotherapy. The combination of chemotherapy and PDT or SDT has shown great potential for cancer treatment. However, the combination of SPDT and chemotherapy for cancer treatment is rarely explored.

PURPOSE

We utilized a natural hydrophobic anti-cancer drug oleanolic acid (OA) and a photosensitizer chlorin e6 (Ce6) through self-assembly technology to form a carrier-free nanosensitizer OC for combined chemotherapy and SPDT for cancer treatment. No studies involving using carrier-free nanomedicine for combined chemotherapy/SPDT have been reported yet.

STUDY DESIGN

After fully characterization of OC, the in vitro and in vivo anti-cancer activities of OC were investigated and the mechanisms of the synergistic therapeutic effects were studied.

METHODS

OC were synthesized through self-assembly technology and characterized by dynamic light scattering (DLS) and an atomic force microscope (AFM). Confocal microscope was used to investigate the intracellular uptake efficiency and the penetration ability of OC. The cell viability of PC9 and 4T1 cells treated with OC under laser and ultrasound (US) irradiation was determined by MTT assay. Furthermore, flow cytometry was performed to detect the reactive oxygen species (ROS) generation, loss of mitochondrial membrane potential (MMP), cell apoptosis and cell cycle arrest. Finally, the anti-tumor therapeutic efficacy of OC was investigated in orthotopic 4T1 breast tumor-bearing mouse model.

RESULTS

OC showed an average particle size of around 100 nm with excellent light stability. OC increased more than 23 times accumulation of Ce6 in cancer cells and had strong tumor penetration ability in three-dimensional (3D) multicellular tumor spheroids (MCTSs). Compared with other therapeutic options, OC showed obvious synergistic inhibitory effects under light and US irradiation in PC9 and 4T1 cells with a significant decrease in IC₅₀ values. Mechanism studies showed that OC could generate high ROS, induce MMP loss, and cause apoptosis and cell cycle arrest. In vivo studies also approved the synergistic therapeutic effects of OC in 4T1 mouse models.

CONCLUSION

Self-assembled carrier-free nanosensitizer OC could be a promising therapeutic agent for synergistic chemo/sono-photodynamic therapy for cancer treatment.

Anti-tumour potential and selectivity of caffeic acid phenethyl ester in osteosarcoma cells

Osteosarcoma is the most common type of bone cancer, and metastasis is widespread decreasing the survival rate. The search for new therapeutic strategies has increased for phytochemicals due to their potential as antioxidants and anticancer properties. Thus, we evaluated the caffeic acid phenethyl ester (CAPE) and caffeic acid's (CA) anticancer properties on UMR-106 murine osteosarcoma cells. The IC₂₅ and IC₅₀ were 1.3 and 2.7 μM for CAPE and 91.0 and 120.0 μM for CA, respectively. This study shows the potential anticancer properties of CAPE and highlights how a phenethyl ester component addition can improve the pharmacological potency in relation to its precursor CA. Our results showed that CAPE was more efficient and selective in reducing the viability of tumor cells compared to the control osteoblasts (MC3T3-E1) (p < 0.05). In addition, CAPE was 44-fold (IC₂₅) and 70-fold (IC₅₀) more cytotoxic than CA. CAPE also decreased ROS generation and cell migration. In summary, CAPE was more selective for tumor cells, preserving normal ones, suggesting its potential role as an anticancer drug.

In Vitro and In Vivo Toxicity Evaluation of Natural Products with Potential Applications as Biopesticides

The use of natural products in agriculture as pesticides has been strongly advocated. However, it is necessary to assess their toxicity to ensure their safe use. In the present study, mammalian cell lines and fish models of the zebrafish (Danio rerio) and medaka (Oryzias latipes) have been used to investigate the toxic effects of ten natural products which have potential applications as biopesticides. The fungal metabolites cavoxin, epi-epoformin, papyracillic acid, seiridin and sphaeropsidone, together with the plant compounds inuloxins A and C and ungeremine, showed no toxic effects in mammalian cells and zebrafish embryos. Conversely, cyclopaldic and α-costic acids, produced by Seiridium cupressi and Dittrichia viscosa, respectively, caused significant mortality in zebrafish and medaka embryos as a result of yolk coagulation. However, both compounds showed little effect in zebrafish or mammalian cell lines in culture, thus highlighting the importance of the fish embryotoxicity test in the assessment of environmental impact. Given the embryotoxicity of α-costic acid and cyclopaldic acid, their use as biopesticides is not recommended. Further ecotoxicological studies are needed to evaluate the potential applications of the other compounds.

Polymeric micelles of a copolymer composed of all-trans retinoic acid, methoxy-poly(ethylene glycol), and b-poly(N-(2 hydroxypropyl) methacrylamide) as a doxorubicin-delivery platform and for combination chemotherapy in breast cancer

Delivery of combination chemotherapeutic agents to the tumor via nanovesicles has the potential for superior tumor suppression and reduced toxicity. Herein, we prepare a block copolymer (mPH-RA) composed of methoxy-poly(ethylene glycol) (mPEG), b-poly(N-(2 hydroxypropyl) methacrylamide) (pHPMA), and all-trans retinoic acid (ATRA) by conjugating ATRA to the pre-formed copolymer, mPEG-b-pHPMA(mP-b-pH). Doxorubicin-loaded micelles, Dox@mP-b-pH, and Dox@mPH-RA were characterized by determining particle size, zeta potential, % DL, EE, Dox release, hemolysis study, and by DSC. The Dox@mPH-RA micelles (mPH-RA: Dox ratios of 10:0.5-2) displayed nano-size (36-45 nm), EE. 26-74%, and DL. 2.9-5.6%. Dox@mPH-RA micelles displayed the highest penetrability and cytotoxicity than free Dox and Dox@mP-b-pH micelles in breast cancer cell lines. Dox@mPH-RA exhibited the highest induction of apoptosis (94.1 ± 3%) than Dox (52.1 ± 4.5%), and Dox@mP-b-pH (81.7 ± 3%), and arrested cells in the highest population in G2 and S phase. Dox@mPH-RA increased the t_1/2 and C_max of Dox and demonstrated improved therapeutic efficacy and highest Dox distribution to the tumor. The Dox@mPH-RA increased the levels of apoptosis markers, caspase 3, 7, Ki-67, and caused the highest DNA fragmentation. The presence of RA improved the micelles' physicochemical properties, Dox-loading ability, and the therapeutic potential in Dox@mPH-RA via the combination therapeutic strategy.

L-carnosine mitigates interleukin-1α-induced dry eye disease in rabbits via its antioxidant, anti-inflammatory, antiapoptotic, and antifibrotic effects

OBJECTIVE

To elucidate the implications of L-carnosine on interleukin-1α (IL-1α)-induced inflammation of lacrimal glands (LGs).

MATERIALS AND METHODS

Forty rabbits were divided equally into four groups: control group (G1), IL-1α (G2), L-carnosine (G3), and L-carnosine plus IL-1α (G4). Several clinical, histopathological, immunohistochemical, morphometric, and biochemical investigations were performed, followed by statistical analysis to diagnose the presence of dry eye disease (DED).

RESULTS

The LGs of G2 rabbits showed degeneration of the acinar cells, increased deposition of collagen fibers, and marked immunoexpression of FasL; elevated levels of interferon-γ, tumor necrosis factor-α, transforming growth factor-β1, and malondialdehyde; and decreased levels of glutathione peroxidase, superoxide dismutase, catalase, and reactive oxygen species compared with those of G1 rabbits. In contrast, administration of L-carnosine to G4 rabbits revealed marked improvement of all previously harmful changes in G2 rabbits, indicating the cytoprotective effects of L-carnosine against IL-1α-induced inflammation of LGs.

CONCLUSIONS

IL-1α induced inflammation of LGs and eye dryness via oxidative stress, proinflammatory, apoptotic, and profibrotic effects, whereas L-carnosine mitigated DED through antioxidant, anti-inflammatory, antiapoptotic, and antifibrotic effects on LGs. Therefore, this work demonstrates for the first time that L-carnosine may be used as adjuvant therapy for the preservation of visual integrity in patients with DED.HighlightsIL-1α induced dry eye disease through its oxidative stress, proinflammatory, apoptotic and profibrotic effects on the lacrimal glands of rabbit.L-carnosine has antioxidant, anti-inflammatory, antiapoptotic and antifibrotic effects.L-carnosine mitigated IL-1α induced dry eye disease via elevating the levels of FasL, IFN-γ, TNF-α, TGFβ1 and MDA as well as reducing the levels of antioxidants (GPx, SOD, and catalase) and ROS in the lacrimal glands of rabbit.L-carnosine could be used as a novel adjuvant therapy for the treatment of dry eye disease.

Thyme oil alleviates Ova-induced bronchial asthma through modulating Th2 cytokines, IgE, TSLP and ROS

Bronchial asthma (BA) is a heterogeneous allergic respiratory disease with diverse inflammatory symptoms, pathology, and responses to treatment. Thyme is a natural product which is consisted of multiple phenolic compounds of therapeutic significance for treatment of cough and bronchitis. This study evaluated the efficacy of thyme oil against ovalbumin (OVA)-induced BA in an experimental rabbit model. Forty male rabbits were divided into four equal groups [control group (G1), OVA (G2), thyme oil (G3), and OVA plus thyme oil (G4)]. Animals were treated for 30 days, and clinical, histopathological (HP), histochemical (HC), immunohistochemical (IHC), morphometric, biochemical and flow cytometry methods were performed, followed by statistical analysis. All used methods revealed normal structure of the lung tissues in rabbits of G1 and G3. In contrast, the clinical examination of G2 rabbits revealed an obvious increase in the respiratory rate, sneezing and wheezing, whereas the HP, HC and IHC techniques exhibited substantial inflammatory changes in the peribronchio-vascular lung tissues with thinning, degeneration, apoptosis (using the TUNEL assay), necrosis, and shedding of the airway epithelium. Furthermore, the morphometric results confirmed significant increases in the numbers of inflammatory cells, goblet cells, eosinophils and apoptotic cells from (12, 0, 2, 2 cells) to (34,10, 16, 18 cells) respectively, as well as the area percentage of collagen fiber deposition and immunoexpression of eotaxin-1/10 high power fields. Additionally, the biochemical results revealed significant increases in the serum levels of TSLP, IL-4, IL-5, IL-9, IL-13, IgE and eotaxin-1 cytokines from (140, 40, 15, 38, 120, 100, 48) pg./ml to (360, 270, 130, 85, 365, 398, 110) pg./ml respectively, while analysis of ROS by flow cytometry revealed remarkable oxidative stress effects in G2 rabbits. On the other hand, treatment of rabbits with thyme oil in G4 substantially alleviated all OVA-induced alterations. Overall, our findings indicate for the first time that thyme oil can ameliorate OVA-induced BA via its immunomodulatory, anti-inflammatory, antiapoptotic, and antioxidant effects on the lung tissues of rabbits.

Hyperthermia induced disruption of mechanical balance leads to G1 arrest and senescence in cells

Human body temperature limits below 40°C during heat stroke or fever. The implications of prolonged exposure to the physiologically relevant temperature (40°C) on cellular mechanobiology is poorly understood. Here, we have examined the effects of heat stress (40°C for 72 h incubation) in human lung adenocarcinoma (A549), mouse melanoma (B16F10), and non-cancerous mouse origin adipose tissue cells (L929). Hyperthermia increased the level of ROS, γ-H2AX and HSP70 and decreased mitochondrial membrane potential in the cells. Heat stress impaired cell division, caused G1 arrest, induced cellular senescence, and apoptosis in all the tested cell lines. The cells incubated at 40°C for 72 h displayed a significant decrease in the f-actin level and cellular traction as compared with cells incubated at 37°C. Also, the cells showed a larger focal adhesion area and stronger adhesion at 40°C than at 37°C. The mitotic cells at 40°C were unable to round up properly and displayed retracting actin stress fibers. Hyperthermia down-regulated HDAC6, increased the acetylation level of microtubules, and perturbed the chromosome alignment in the mitotic cells at 40°C. Overexpression of HDAC6 rescued the cells from the G1 arrest and reduced the delay in cell rounding at 40°C suggesting a crucial role of HDAC6 in hyperthermia mediated responses. This study elucidates the significant role of cellular traction, focal adhesions, and cytoskeletal networks in mitotic cell rounding and chromosomal misalignment. It also highlights the significance of HDAC6 in heat-evoked senile cellular responses.

Self-assembled and pH-responsive polymeric nanomicelles impart effective delivery of paclitaxel to cancer cells

Chemotherapy is an essential component of breast cancer therapy, but it is associated with serious side effects. Herein, a pluronic F68-based pH-responsive, and self-assembled nanomicelle system was designed to improve the delivery of paclitaxel (PTX) to breast cancer cells. Two pH-responsive pluronic F68-PTX conjugates i.e. succinoyl-linked conjugate (F68-SA-PTX) and cis-aconityl-linked conjugate (F68-CAA-PTX) were designed to respond the varying pH-environment in tumour tissue. Although both the linkers showed pH-sensitivity, the F68-CAA-PTX exhibited superior pH-sensitivity over the F68-SA-PTX and achieved a more selective release of PTX from the self-assembled nanomicelles. The prepared nanomicelles were characterized by dynamic light scattering, transmittance electron microscopy, differential scanning calorimetry and powder X-ray diffraction techniques. The anticancer activity of prepared nanomicelles and pure PTX were evaluated by 2D cytotoxicity assay against breast cancer cell line MDA-MB-231 and in the real tumour environments i.e. 3D tumor spheroids of MDA-MB-231 cells. The highest cytotoxicity effect of PTX was observed with F68-CAA-PTX nanomicelles followed by F68-SA-PTX and free PTX. Further, the F68-CAA-PTX nanomicelles also induced significant apoptosis with a combination of increase in ROS generation, decrease in the depolarisation of MMP and G2/M cell cycle arrest. These observed results provide a new insight for breast cancer treatment using pluronic nanomicelles.

Therapeutic Potential of Reactive Oxygen Species: State of the Art and Recent Advances

In the last decade, several studies have proven that when at low concentration reactive oxygen species (ROS) show an adaptive beneficial effect and posited the idea that they can be utilized as inexpensive and convenient inducers of tissue regeneration. On the other hand, the recent discovery that cancer cells are more sensitive to oxidative damage paved the way for their use in the selective killing of tumor cells, and sensors to monitor ROS production during cancer treatment are under extensive investigation. Nevertheless, although ROS-activated signaling pathways are well established, less is known about the mechanisms underlying the switch from an anabolic to a cytotoxic response. Furthermore, a high variability in biological response is observed between different modalities of administration, cell types, donor ages, eventual concomitant diseases, and external microenvironment. On the other hand, available preclinical studies are scarce, whereas the quest for the most suitable systems for in vivo delivery is still elusive. Furthermore, new strategies to control the temporal pattern of ROS release need to be developed, if considering their tumorigenic potential. This review initially discusses ROS mechanisms of action and their potential application in stem cell biology, tissue engineering, and cancer therapy. It then outlines the state of art of ROS-based drugs and identifies challenges faced in translating ROS research into clinical practice.

Exposure of calcium carbide induces apoptosis in mammalian fibroblast L929 cells

Inspite of various health warnings from Government and health organizations, Calcium carbide (CaC₂) is still the most commonly and widely used artificial fruit ripener, probably due to its easy availability, low cost and convenience of usage. Assessment of the hazardous effects of the CaC₂ applications for fruit ripening has been a matter of interest since long. Several in vivo studies have reported the toxicological outcomes such as histopathological changes in lungs and kidneys, haematological and immunological responses, upon exposure with CaC₂. However, a well-controlled study investigating the effects of CaC₂ under in-vitro setup was lacking. Hence, this study has been conducted to explore the toxicity associated cellular events in L929 cells exposed with varying concentrations of CaC₂ (0.00312-0.2 μg/μl) for 24 h exposure time. A 23.14% reduction in cell viability was observed at the highest dose of CaC₂. A similar trend in cellular stress levels at 0.2 μg/μl dose was observed in terms of rounded cellular morphology and decreased adherence as compared to the control. Furthermore, Annexin V FITC/PI staining and subsequent confocal imaging revealed a similar trend of CaC₂ induced apoptosis in a dose dependent manner. A gradual elevation of intracellular ROS has also been observed up to 0.025 μg/μl dose. Thus, the study concludes that short term CaC₂ exposure may increase the cellular oxidative stress and disturb the redox balance of the cell which then undergoes apoptosis. The study concludes that the exposure of CaC₂ can be associated with severe diseases and suggests to stop the uses of CaC₂ as fruit ripening agent.

AAPH or Peroxynitrite-Induced Biorelevant Oxidation of Methyl Caffeate Yields a Potent Antitumor Metabolite

Hydroxycinnamic acids represent a versatile group of dietary plant antioxidants. Oxidation of methyl-p-coumarate (pcm) and methyl caffeate (cm) was previously found to yield potent antitumor metabolites. Here, we report the formation of potentially bioactive products of pcm and cm oxidized with peroxynitrite (ONOO¯), a biologically relevant reactive nitrogen species (RNS), or with α,α'-azodiisobutyramidine dihydrochloride (AAPH) as a chemical model for reactive oxygen species (ROS). A continuous flow system was developed to achieve reproducible in situ ONOO¯ formation. Reaction mixtures were tested for their cytotoxic effect on HeLa, SiHa, MCF-7 and MDA-MB-231 cells. The reaction of pcm with ONOO¯ produced two fragments, an o-nitrophenol derivative, and a new chlorinated compound. Bioactivity-guided isolation from the reaction mixture of cm with AAPH produced two dimerization products, including a dihydrobenzofuran lignan that exerted strong antitumor activity in vitro, and has potent in vivo antimetastatic activity which was previously reported. This compound was also detected from the reaction between cm and ONOO¯. Our results demonstrate the ROS/RNS dependent formation of chemically stable metabolites, including a potent antitumor agent (5), from hydroxycinnamic acids. This suggests that diversity-oriented synthesis using ROS/RNS to obtain oxidized antioxidant metabolite mixtures may serve as a valid natural product-based drug discovery strategy.

Synergetic Influence of Bismuth Oxide Nanoparticles, Cisplatin and Baicalein-Rich Fraction on Reactive Oxygen Species Generation and Radiosensitization Effects for Clinical Radiotherapy Beams

Purpose

This study aimed to quantify synergetic effects induced by bismuth oxide nanoparticles (BiONPs), cisplatin (Cis) and baicalein-rich fraction (BRF) natural-based agent on the reactive oxygen species (ROS) generation and radiosensitization effects under irradiation of clinical radiotherapy beams of photon, electron and HDR-brachytherapy. The combined therapeutic responses of each compound and clinical radiotherapy beam were evaluated on breast cancer and normal fibroblast cell line.

Methods

In this study, individual BiONPs, Cis, and BRF, as well as combinations of BiONPs-Cis (BC), BiONPs-BRF (BB) and BiONPs-Cis-BRF (BCB) were treated to the cells before irradiation using HDR brachytherapy with 0.38 MeV iridium-192 source, 6 MV photon beam and 6 MeV electron beam. The individual or synergetic effects from the application of the treatment components during the radiotherapy were elucidated by quantifying the ROS generation and radiosensitization effects on MCF-7 and MDA-MB-231 breast cancer cell lines as well as NIH/3T3 normal cell line.

Results

The ROS generated in the presence of Cis stimulated the most substantial amount of ROS compared to the BiONPs and BRF. Meanwhile, the combination of the components had induced the higher ROS levels for photon beam than the brachytherapy and electron beam. The highest ROS enhancement relative to the control is attributable to the presence of BC combination in MDA-MB-231 cells, in comparison to the BB and BCB combinations. The radiosensitization effects which were quantified using the sensitization enhancement ratio (SER) indicate the highest value by BC in MCF-7 cells, followed by BCB and BB treatment. The radiosensitization effects are found to be more prominent for brachytherapy in comparison to photon and electron beam.

Conclusion

The BiONPs, Cis and BRF are the potential radiosensitizers that could improve the efficiency of radiotherapy to eradicate the cancer cells. The combination of these potent radiosensitizers might produce multiple effects when applied in radiotherapy. The BC combination is found to have the highest SER, followed by the BCB combination. This study is also the first to investigate the effect of BRF in combination with BiONPs (BB) and BC (BCB) treatments.

Antioxidant and Biological Activities of Acacia saligna and Lawsonia inermis Natural Populations

Acacia saligna and Lawsonia inermis natural populations growing in Northern Saudi Arabia might be a valuable source of polyphenols with potent biological activities. Using high-performance liquid chromatography-diode array detection (HPLC-DAD), several polyphenols were detected tentatively in considerable amounts in the methanolic leaf extracts of A. saligna and L. inermis. A. saligna mainly contained rutoside, hyperoside, quercetin 3-glucuronide, gallic acid and p-coumaric acid, whereas those of L. inermis contained apigenin 5-glucoside, apigetrin and gallic acid. Strong antioxidant activities were found in the leaf extracts of both species due to the presence of hyperoside, quercetin 3-glucuronide, gallic acid, isoquercetin, p-coumaric acid, quercitrin and rutoside. A. saligna and L. inermis leaf extracts as well as hyperoside, apigenin 5-glucoside, and quercetin 3-glucuronide significantly reduced reactive oxygen species accumulation in all investigated cancer cells compared to the control. Methanolic leaf extracts and identified polyphenols showed antiproliferative and cytotoxic activities against cancer cells, which may be attributed to necrotic cell accumulation during apoptotic periods. Antibacterial activities were also found in both species leaf extracts and were twice as high in A. saligna than L. inermis due to the high composition of rutoside and other polyphenols. Finally, strong antifungal activities were detected, which were associated with specific phenols such as rutoside, hyperoside, apigenin 5-glucoside and p-coumaric acid. This is the first study exploring the polyphenolic composition of A. saligna and L. inermis natural populations in northern Saudi Arabia and aiming at the detection of their biological activities.

Inhibitory Effects of AF-343, a Mixture of Cassia tora L., Ulmus pumila L., and Taraxacum officinale, on Compound 48/80-Mediated Allergic Responses in RBL-2H3 Cells

The purpose of this study was to determine the antiallergic effects of AF-343, a mixture of natural plant extracts from Cassia tora L., Ulmus pumila L., and Taraxacum officinale, on rat basophilic leukemia (RBL-2H3) cells. The inhibitory effects on cell degranulation, proinflammatory cytokine secretion, and reactive oxygen species (ROS) production were studied in compound 48/80-treated RBL-2H3 cells. The bioactive compounds in AF-343 were also identified by HPLC–UV. AF-343 was found to effectively suppress compound 48/80-induced β-hexosaminidase release, and interleukin (IL)-4 and tumor necrosis factor-α (TNF-α) production in RBL-2H3 cells. In addition, AF-343 exhibited DPPH free radical scavenging effects in vitro (half-maximal inhibitory concentration (IC₅₀) = 105 μg/mL) and potently inhibited compound 48/80-induced cellular ROS generation in a 2′,7′-dichlorofluorescein diacetate (DCFH-DA) assay. Specifically, treatment with AF-343 exerted stronger antioxidant effects in vitro and antiallergic effects in cells than treatment with three single natural plant extracts. Furthermore, AF-343 was observed to contain bioactive compounds, including catechin, aurantio-obtusin, and chicoric acid, which have been reported to elicit antiallergic responses. This study reveals that AF-343 attenuates allergic responses via suppression of β-hexosaminidase release, IL-4 and TNF-α secretion, and ROS generation, perhaps through mechanisms related to catechin, aurantio-obtusin, and chicoric acid. The results indicate that AF-343 can be considered a treatment for various allergic diseases.

Is the Way to Fight Cancer Paved with Gold? Metal-Based Carbene Complexes with Multiple and Fascinating Biological Features

Herein, we report the synthesis and the multiple anti-tumor properties of new gold and silver carbene complexes. The chemical modifications, grounded on our previous studies, led us to identify a good lead complex, gold-based, whose biological features are very exciting and promising in the anti-cancer research and could be further developed. Indeed, the bis-[4,5-dichloro-(N-methyl-N’(2-hydroxy-2-phenyl)ethyl-imidazole-2-ylidene)gold(I)]⁺[dichloro-gold]⁻ (AuL7) complex possesses the ability to interfere with at least three important and different intracellular targets, namely the human topoisomerases I and II and tubulin, which are able to modulate metabolic processes not directly correlated each other. We proved that the modifications of the ligands structure in AuL7, with respect to another already published complex, i.e., bis-[4,5-dichloro-(N-methyl-N’(cyclopentane-2ol)-imidazole-2-ylidine)gold(I)]⁺[dichloro-gold]⁻ (AuL4), produce a different behavior toward tubulin-polymerization process, since AuL7 is a tubulin-polymerization inhibitor and AuL4 a stabilizer, with the final same result of hampering the tumor growth. Taken together, our outcomes designate AuL7 as a promising compound for the development of multi-targeted anti-cancer therapies.

Increased formation of reactive oxygen species during tumor growth: Ex vivo low-temperature EPR and in vivo bioluminescence analyses

Previous studies have shown that reactive oxygen species (ROS) such as superoxide or hydrogen peroxide generated at low levels can exert a tumor-promoting role via a redox-signaling mechanism. Reports also suggest that both tumorigenesis and tumor growth are associated with enhanced ROS formation. However, whether ROS levels or ROS-derived oxidative marker levels increase during tumor growth remains unknown. In this study, in vivo bioluminescence imaging with a boronate-based pro-luciferin probe was used to assess ROS formation. Additionally, probe-free cryogenic electron paramagnetic resonance was used to quantify a characteristic aconitase [3Fe4S]⁺ center that arises in the tumor tissue of mouse xenografts from the reaction of the native [4Fe4S]²⁺ cluster with superoxide. Results indicated that tumor growth is accompanied by increased ROS formation, and revealed differences in oxidant formation in the inner and outer sections of tumor tissue, respectively, demonstrating redox heterogeneity. Studies using luciferin and pro-luciferin probes enabled the assessment of tumor size, ROS formation, and bioenergetic status (e.g., ATP) in luciferase-transfected mice tumor xenografts. Probe-free ex vivo low-temperature electron paramagnetic resonance can also be translated to clinical studies.

Gamma Tocopherol Reduced Chemotherapeutic-Induced ROS in an Ovarian Granulosa Cell Line, But Not in Breast Cancer Cell Lines In Vitro

Doxorubicin and cyclophosphamide are used to treat breast cancer, but they also cause infertility through off-target cytotoxicity towards proliferating granulosa cells that surround eggs. Each chemotherapeutic generates reactive oxygen species (ROS) but the effects of the combination, or the antioxidants alpha (αToc) and gamma tocopherol (γToc) on ROS in breast cancer or ovarian cells are unknown. Human breast cancer (MCF7, T47D) and ovarian cancer (OVCAR, COV434) cells were loaded with DCDFA and exposed (1, 2, 3, 24 h) to the MCF7-derived EC25 values of individual agents, or to combinations of these. ROS were quantified and viable cells enumerated using crystal violet or DAPI. Each chemotherapeutic killed ~25% of MCF7, T47D and OVCAR cells, but 57 ± 2% (doxorubicin) and 66 ± 2% (cyclophosphamide) of the COV434 granulosa cells. The combined chemotherapeutics decreased COV434 cell viability to 34 ± 5% of control whereas doxorubicin + cyclophosphamide + γToc reduced ROS within 3 h (p < 0.01) and reduced cytotoxicity to 54 ± 4% (p < 0.05). αToc was not cytotoxic, whereas γToc killed ~25% of the breast cancer but none of the ovarian cells. Adding γToc to the combined chemotherapeutics did not change ROS or cytotoxicity in MCF7, T47D or OVCAR cells. The protection γToc afforded COV434 granulosa cells against chemotherapy-induced ROS and cytotoxicity suggests potential for fertility preservation.

Implications of dichlorofluorescein photoinstability for detection of UVA-induced oxidative stress in fibroblasts and keratinocyte cells

Pre-incubation with 10 μM DCFDA for 30 min in PBS was sufficient to generate a sensitive and reproducible standard curve for detection of UVA-induced ROS in HaCaT and HPF cells, with no effects on cell viability or morphology.

A Novel Approach to Improving the Reliability of Manual Semen Analysis: A Paradigm Shift in the Workup of Infertile Men

Conventional semen analysis (SA) is an essential component of the male infertility workup, but requires laboratories to rigorously train and monitor technicians as well as regularly perform quality assurance assessments. Without such measures there is room for error and, consequently, unreliable results. Furthermore, clinicians often rely heavily on SA results when making diagnostic and treatment decisions, however conventional SA is only a surrogate marker of male fecundity and does not guarantee fertility. Considering these challenges, the last several decades have seen the development of many advances in SA methodology, including tests for sperm DNA fragmentation, acrosome reaction, and capacitation. While these new diagnostic tests have improved the scope of information available to clinicians, they are expensive, time-consuming, and require specialized training. The latest advance in laboratory diagnostics is the measurement of seminal oxidation-reduction potential (ORP). The measurement of ORP in an easy, reproducible manner using a new tool called the Male Infertility Oxidative Stress System (MiOXSYS) has demonstrated ORP's potential as a feasible adjunct test to conventional SA. Additionally, the measurement of ORP by this device has been shown to be predictive of both poor semen quality and male infertility. Assessing ORP is a novel approach to both validating manual SA results and identifying patients who may benefit from treatment of male oxidative stress infertility.

ATM Deficiency Accelerates DNA Damage, Telomere Erosion, and Premature T Cell Aging in HIV-Infected Individuals on Antiretroviral Therapy

HIV infection leads to a phenomenon of inflammaging, in which chronic inflammation induces an immune aged phenotype, even in individuals on combined antiretroviral therapy (cART) with undetectable viremia. In this study, we investigated T cell homeostasis and telomeric DNA damage and repair machineries in cART-controlled HIV patients at risk for inflammaging. We found a significant depletion of CD4 T cells, which was inversely correlated with the cell apoptosis in virus-suppressed HIV subjects compared to age-matched healthy subjects (HS). In addition, HIV CD4 T cells were prone to DNA damage that extended to chromosome ends-telomeres, leading to accelerated telomere erosion-a hallmark of cell senescence. Mechanistically, the DNA double-strand break (DSB) sensors MRE11, RAD50, and NBS1 (MRN complex) remained intact, but both expression and activity of the DNA damage checkpoint kinase ataxia-telangiectasia mutated (ATM) and its downstream checkpoint kinase 2 (CHK2) were significantly suppressed in HIV CD4 T cells. Consistently, ATM/CHK2 activation, DNA repair, and cellular functions were also impaired in healthy CD4 T cells following ATM knockdown or exposure to the ATM inhibitor KU60019 in vitro, recapitulating the biological effects observed in HIV-derived CD4 T cells in vivo. Importantly, ectopic expression of ATM was essential and sufficient to reduce the DNA damage, apoptosis, and cellular dysfunction in HIV-derived CD4 T cells. These results demonstrate that failure of DSB repair due to ATM deficiency leads to increased DNA damage and renders CD4 T cells prone to senescence and apoptotic death, contributing to CD4 T cell depletion or dysfunction in cART-controlled, latent HIV infection.

Inhibition of TRF2 accelerates telomere attrition and DNA damage in naïve CD4 T cells during HCV infection

T cells play a crucial role in viral clearance and vaccine responses; however, the mechanisms that regulate their homeostasis during viral infections remain unclear. In this study, we investigated the machineries of T-cell homeostasis and telomeric DNA damage using a human model of hepatitis C virus (HCV) infection. We found that naïve CD4 T cells in chronically HCV-infected patients (HCV T cells) were significantly reduced due to apoptosis compared with age-matched healthy subjects (HSs). These HCV T cells were not only senescent, as demonstrated by overexpression of aging markers and particularly shortened telomeres; but also DNA damaged, as evidenced by increased dysfunctional telomere-induced foci (TIF). Mechanistically, the telomere shelterin protein, in particular telomeric repeat binding factor 2 (TRF2) that functions to protect telomeres from DNA damage, was significantly inhibited posttranscriptionally via the p53-dependent Siah-1a ubiquitination. Importantly, knockdown of TRF2 in healthy T cells resulted in increases in telomeric DNA damage and T-cell apoptosis, whereas overexpression of TRF2 in HCV T cells alleviated telomeric DNA damage and T-cell apoptosis. To the best of our knowledge, this is the first report revealing that inhibition of TRF2 promotes T-cell telomere attrition and telomeric DNA damage that accelerates T-cell senescent and apoptotic programs, which contribute to naïve T-cell loss during viral infection. Thus, restoring the impaired T-cell telomeric shelterin machinery may offer a new strategy to improve immunotherapy and vaccine response against human viral diseases.