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Background:: Tetrapyrrolic compounds, such as porphyrins and metalloporphyrins, are highly interesting for pharmaceutical chemistry designs considering their good biocompatibility and therapeutic potential. Objective:: The aim of the present work was a preliminary in vitro evaluation of some unsymmetrical porphyrins and the corresponding symmetrical structures as potential candidates for the photodynamic therapy of malignant tumors. Methods:: The biocompatibility of compounds was assessed in terms of their in vitro effect on the viability and proliferation of breast human carcinoma MCF-7 cells and human normal peripheral blood mononuclear cells. Results:: Results indicated that unsymmetrical and symmetrical porphyrins were non-toxic against tumor MCF-7 cells in the concentration range of 0.2–2μM, making them valuable candidates for further development as photosensitizers for PDT in tumors. Moreover, unsymmetrical compounds tended to restore the response of normal and tumor cells affected by the vehicle (dimethyl sulfoxide) used for the initial solubilization of porphyrins, while the symmetrical compounds were less active in this respect. Conclusion:: Unsymmetrical A3B type porphyrins prove enhanced capacity as potential theranostic agents in interaction with human carcinoma MCF-7 cells, despite reduced differences with the corresponding symmetrical form.

Rheumatoid arthritis (RA) is an autoimmune disease with an important inflammatory component accompanied by deregulated redox-dependent signaling pathways that are feeding back into inflammation. In this context, we bring into focus the transcription factor NRF2, a master redox regulator that exerts exquisite antioxidant and anti-inflammatory effects. The review does not intend to be exhaustive, but to point out arguments sustaining the rationale for applying an NRF2-directed co-treatment in RA as well as its potential limitations. The involvement of NRF2 in RA is emphasized through an analysis of publicly available transcriptomic data on NRF2 target genes and the findings from NRF2-knockout mice. The impact of NRF2 on concurrent pathologic mechanisms in RA is explained by its crosstalk with major redox-sensitive inflammatory and cell death-related pathways, in the context of the increased survival of pathologic cells in RA. The proposed adjunctive therapy targeted to NRF2 is further sustained by the existence of promising NRF2 activators that are in various stages of drug development. The interference of NRF2 with conventional anti-rheumatic therapies is discussed, including the cytoprotective effects of NRF2 for alleviating drug toxicity. From another perspective, the review presents how NRF2 activation would be decreasing the efficacy of synthetic anti-rheumatic drugs by increasing drug efflux. Future perspectives regarding pharmacologic NRF2 activation in RA are finally proposed., GM, EM, CMN, IVN, EMD and AC were supported by the Romanian Ministry of Research, Innovation and Digitization through the European Regional Development Fund, Competitiveness Operational Program 2014–2020 [the REDBRAIN project, ID: P_37_732].

This study aimed to assess the in vitro biocompatibility of titanium (Ti) alloy orthodontic mini-implants by correlating human osteoblasts (HOb) response with chemical composition and surface morphology of mini-implants. HOb were cultivated with or without custom-made and commercial mini-implants, discs and filings. The surface morphology and chemical composition of the implants were assessed under the scanning electron microscopy (SEM) with energy-dispersive X-ray (EDX) microanalysis system. Cell viability, adhesion and proliferation were analyzed by optical microscopy and flow cytometry. 3-(4,5-Dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) reduction and lactate dehydrogenase (LDH) release tests were used to assess the cytotoxicity of discs and filings-treated culture medium. Shape, adhesion, and multiplication of HOb were not significantly altered by the presence of mini-implants, discs or filings in culture, even though Ti alloy may exert in vitro a low cytotoxic effect on HOb adhered to discs. Morphology analysis by SEM demonstrated that custom-made mini-implants' surface differs from that of commercial mini-screws in terms of surface finish and roughness, whilst EDX analysis showed largely similar percentages of Ti, aluminum and vanadium for the two types of implants. No major differences were noticed regarding the effect exerted in vitro on HOb by the investigated implants. The new mini-implants have a convenient in vitro cytotoxicity profile on HOb.

This study include in the same frame promising structures tailored as photoactive agents for photodynamic therapy of cancer versus one of the most versatile cell lines from experimental point of view, fibroblasts type, subcutaneous connective tissues- L929. Transmembrane potential was studied establishing important features in the behavior of chemical vectors against cultured cells via membranar media. Two amphiphilic porphyrins, 5,15-bis-(4-hydroxy-3-methoxyphenyl)-10,20-bis-(4-carboxymethylphenyl)porphyrin and Zn(II)-5,15-bis-(4-hydroxy-3-methoxyphenyl)-10,20-bis-(4-carboxymethylphenyl)porphyrin were assessed in terms of the effect on membrane potential. The comparative effect of free base porphyrin and metalloporphyrin with amphiphilic structure, reveal hyperpolarization phenomena and bring informations about consequences of active compound concentration against cell membrane.

Photodynamic therapy (PDT), a highly targeted therapy with acceptable side effects, has emerged as a promising therapeutic option in oncologic pathology. One of the issues that needs to be addressed is related to the complex network of cellular responses developed by tumor cells in response to PDT. In this context, this study aims to characterize in vitro the stressors and the corresponding cellular responses triggered by PDT in the human colon carcinoma HT29 cell line, using a new asymmetric porphyrin derivative (P2.2) as a photosensitizer. Besides investigating the ability of P2.2-PDT to reduce the number of viable tumor cells at various P2.2 concentrations and fluences of the activating light, we assessed, using qRT-PCR, the expression levels of 84 genes critically involved in the stress response of PDT-treated cells. Results showed a fluence-dependent decrease of viable tumor cells at 24 h post-PDT, with few cells that seem to escape from PDT. We highlighted following P2.2-PDT the concomitant activation of particular cellular responses to oxidative stress, hypoxia, DNA damage and unfolded protein responses and inflammation. A web of inter-connected stressors was induced by P2.2-PDT, which underlies cell death but also elicits protective mechanisms that may delay tumor cell death or even defend these cells against the deleterious effects of PDT.

© 2021 Milanesi et al., [Purpose]: Chronic low-grade inflammation and oxidative stress are present in most of the pathologic mechanisms underlying non-communicable diseases. Inflammation and redox biomarkers might therefore have a value in disease prognosis and therapy response. In this context, we performed a case–control study for assessing in whole blood the expression profile of inflammation and redox-related genes in elderly subjects with various comorbidities. [Patients and Methods]: In the blood of 130 elderly subjects with various pathologies (cardiovascular disease, hypertension, dyslipidemia including hypercholesterolemia, type 2 diabetes mellitus), kept under control by polyvalent disease-specific medication, we investigated by pathway-focused qRT-PCR a panel comprising 84 inflammation-related and 84 redox-related genes. [Results]: The study highlights a distinctive expression profile of genes critically involved in NF-κB-mediated inflammation and redox signaling in the blood of patients with cardiovascular disease, characterized by significant down-regulation of the genes NFKB2, NFKBIA, RELA, RELB, AKT1, IRF1, STAT1, CD40, LTA, TRAF2, PTGS1, ALOX12, DUOX1, DUOX2, MPO, GSR, TXNRD2, HSPA1A, MSRA, and PDLIM1. This gene expression profile defines the transcriptional status of blood leukocytes in stable disease under medication control, without discriminating between disease- and therapy-related changes. [Conclusion]: The study brings preliminary proof on a minimally invasive strategy for monitoring disease in patients with cardiovascular pathology, from the point of view of inflammation or redox dysregulation in whole blood., Research and publication of the present study was funded by the Romanian Ministry of Education and Research through the European Regional Development Fund, Competitiveness Operational Program 2014–2020 [the REDBRAIN project, ID: P_37_732] and through Programme 1 – Development of the national researchdevelopment system [grant 7PFE/2018].

The use of porphyrinic compounds for photodynamic therapy (PDT) in cancer is well documented, but the aggregation tendency in physiologically-relevant media impedes on their medical use. The present study argues for the use of atomic force microscopy (AFM) for the evaluation of the aggregation tendency in terms of topography, self-similarity (fractal behavior) and textural properties of some promising A3B-type porphyrinic compounds, previously described by our group. It was found that the samples are isotropic and rough enough to favor cell adhesion. Despite having different aggregation tendencies, the P and Zn(II)P compounds (5 µM) were similarly incorporated into tumour cells (HT-29 human colon carcinoma and U-87 MG human glioblastoma), as demonstrated by flow cytometry data. Results suggest that there might be an aggregation, “window” that does not impede on the interaction of the investigated porphyrins with tumor cells.

Background It is known that γ radiation is rapidly triggering in cells and in the surrounding medium a hydrogen peroxide burst through water radiolysis, which may have early and late consequence on the viability and functions of irradiated cells. Investigations on monocytes and macrophages are of utmost importance for assessing radiation risks, considering that they are highly responsive to danger/damage signals, are master regulators of the immune response and actively contribute to repair processes in tissues damaged by radiation. Aim In the present study we investigated the expression changes of redox genes in human SC monocytes exposed in vitro to γ rays, aiming to identify delayed disturbances of the redox gene network in irradiated cells. Methods SC monocytes were exposed to γ radiation in the dose range of 1–5 Gy, at various dose rates (1.6 Gy/h, 4 Gy/h and 10 Gy/h). Cells were further cultivated and were analyzed at various time points after irradiation (24 h and 48 h) regarding cell viability and the expression profile of 84 redox genes critically involved in oxidative stress and antioxidant responses, addressing ROS metabolism, oxidative stress responsive genes, antioxidant genes and pathway activity signature genes. Results Over-expression of particular genes encoding various members of the NADPH oxidase family or myeloperoxidase evidenced an increased potential of irradiated cells to generate reactive oxygen or nitrogen species, especially superoxide anion. Alternatively, up-regulation of genes encoding antioxidant molecules indirectly proved that an increased oxidative activity occurred in irradiated monocytes. Redox-mediated cellular deregulation was evidenced by the over-expression of the BNIP3 gene which is involved in cell death by apoptosis or autophagy, and was complemented by the up-regulation of the DUSP1 gene involved in cell cycle arrest and functional silencing of monocytes. At lower doses and dose rates, an enhanced molecular fingerprint of antioxidant responses mediated by the cytoprotective transcription factor NRF2 was found, albeit not being able to avoid the observed reduction of viable cells in irradiated cultures. Moreover, only a low transcriptional activity of NRF2 was registered at higher doses which probably inflicted profound oxidative damages that compromised critical cellular defense mechanisms. Conclusion Pathway-focused analysis of redox gene expression allowed us to highlight delayed oxidative alterations in monocytes exposed in vitro to γ rays, indicating a persistent oxidative activity after irradiation. Moreover, we emphasized the necessity to boost the endogenous antioxidant system in normal cells exposed to higher doses of γ rays, in order to protect them against the deleterious effects of radiation. A therapeutic option might be the pharmacological activation of the transcription factor NRF2 which can rapidly react to even small increases in intracellular oxidants, and regulates the expression of many antioxidant and cytoprotective genes.

Introduction Photodynamic therapy (PDT) has emerged as efficient and reasonably safe targeted therapeutic strategy in solid tumours. Briefly, a non-toxic photosensitizer is injected and then is activated at tumor-site only by exposure to tissue-penetrating red light. Cytotoxic singlet oxygen is formed, hence triggering massive death of tumour cells. Material and methods A new porphyrinic compound (P2.2), previously described by us (Boscencu 2017) in Molecules 22.11:1815), was used as photosensitizer in U-87 MG human glioblastoma cells and HT-29 human colon carcinoma cells. A good concentration-dependent uptake of the fluorescent P2.2 compound by the investigated cells was demonstrated by flow cytometry. Cells loaded with 10 µM P2.2 were subjected to in vitro PDT using the MODULIGHT 6600 equipment at fluences of 5 to 10 J/cm2. For mechanistic studies, cells were investigated at 3–6 hours post-PDT regarding viability, morphology and gene expression. The gene expression profile was assessed by pathway-focused PCR array (Stress and Toxicity Pathway Finder, QIAGEN), addressing 84 genes critically involved in oxidative, osmotic, hypoxic and inflammatory stress, in cell death by apoptosis, necrosis and autophagy, in DNA damage and heat shock proteins/unfolded protein response. Results and discussions Viability tests indicated that cell death arise within 6 hours post-PDT, but massive cell death occurs more than 48 hours post-PDT. The singlet oxygen burst triggered an early activation of some protective mechanisms against oxidative stress (full signature of the cytoprotective NRF2), hypoxia (SERPINE1) and osmotic stress (HSPA4L). Apoptosis (TNFα mediated), necrosis, autophagy and DNA damage (DDIT3) responses were highlighted. Interestingly, a complex inflammatory network was triggered by PDT (CXCL8, TNF, IL1), possibly associated to oxidative stress through NF-kB. These protective responses could be responsible for the delayed massive death of cells subjected to PDT. Conclusion In response to PDT, glioblastoma and colon carcinoma cells developed in vitro various protective mechanisms against a complex web of stressors. Genes overexpressed in response to PDT might be candidates for co-therapies aiming to increase PDT efficacity. It seems reasonable that inhibition of endogenous NRF2-mediated antioxidant mechanisms could be an option for improving oxidative stress-mediated PDT. Acknowledgement Work was supported by the M-ERA.NET Grant 52/2016 (NANOTHER)

Polyphenols are largely studied for their beneficial action in various pathologies, but the correlation with their effects on cell membranes is still elusive. In the present study we assessed the effects exerted in vitro by quercetin, epigallocatechin gallate and curcumin on membrane fluidity and transmembrane potential of human umbilical vein endothelial cells and Jurkat T lymphoblasts, in experimental conditions mimicking diabetes mellitus, i.e. high glucose conditions or increased concentration of advanced glycation end products. Results showed that the investigated polyphenols had beneficial effects on cell membranes altered in diabetic conditions, by restoring transmembrane potential and by membrane "stiffening". Moreover, they limited the release of pro-inflammatory factors, like monocyte chemotactic protein-1. These effects were more obvious for cells exposed to advanced glycation end products specific for the late stages of diabetes. Apparently, the inhibitory action of polyphenols on lipid peroxidation was associated with a decrease of membrane fluidity. Concluding, our in vitro study highlighted the potential beneficial action of polyphenols mainly in the late stages of diabetes, exerted at the level of membrane fluidity and transmembrane potential, accompanied by an anti-inflammatory effect on endothelial and immune cells.

Trichotecenes are mycotoxins produced by Fusarium sp., which may contaminate animal feeds and human food. A feeding trial was conducted to evaluate the effect of a fusarotoxin-contaminated diet, and to explore the counteracting potential of a calcium fructoborate (CFrB) additive on performance, typical health biochemistry parameters and immune response in weaned pigs. A naturally contaminated maize, containing low doses of deoxynivalenol, zearalenone, fumonisins and T-2/HT-2 toxins (1790, 20, 0·6 and 90 parts per billion), was included in a maize–soyabean meal diet, and given ad libitum to eight weaned piglets (two groups: four pigs/group) for a period of 24 d. CFrB was administered to one of the contaminated groups and to another four piglets as a daily supplement, following the manufacturer's recommendation. A decrease in performance was observed in contaminated animals at this concentration of feed toxins, which was ameliorated by the dietary CFrB supplementation. Fusarium toxins also altered the pig immune response by increasing (P ex vivo peripheral blood mononuclear cell proliferation (111·7 % in comparison with control), the respiratory burst of porcine granulocytes (15·4 % for responsive cells v. 5·1 % for unstimulated cells and 70·95 v. 22·65 % for stimulated cells, respectively), the percentage of peripheral T, CD3+, CD3+CD4+ and CD3+CD8+ subsets and the synthesis of IL-1β, TNF-α and IL-8 (123·8, 217·1 and 255·1 %, respectively). The diet containing the CFrB additive reduced these exacerbated cellular immune responses induced by Fusarium toxins. However, consumption of CFrB did not counteract the effect of mycotoxins on biochemistry parameters, and increased plasma IgM and IgG of contaminated pigs.

A series of cyclometallated 2-phenylpyridine Pt(II) complexes having N-benzoyl thiourea derivatives as ancillary ligands were prepared and characterised by elemental analysis, IR and UV–Vis spectroscopy, 1H and 13C NMR spectroscopy as well as by X-ray diffraction on single-crystal. All complexes were obtained as a single isomer with N atom of the 2-phenylpyridine ligand and S atom of the N-benzoyl thiourea derivatives coordinated in trans positions to the platinum metal as evidenced by using X-ray crystallography and NMR spectroscopy. All Pt(II) complexes show good luminescence properties at room temperature, both in dichloromethane solution and in solid state.

The study aimed to assess biophysical changes that take place in the peripheral blood mononuclear cell (PBMC) membranes when exposed in vitro to 10 μM quercetin or epigallocatechin gallate (EGCG) for 24 and 48 h. PBMCs isolated from hypercholesterolemia patients were compared to those from normocholesterolemia subjects. The membrane fluidity and transmembrane potential were evaluated and the results were correlated with biochemical parameters relevant to oxidative stress, assessed in the patients’ plasma. The baseline value of PBMC membrane anisotropy for the hypercholesterolemia patients was lower than that of the control group. These results correlated with the plasma levels of advanced glycation end products, which were significantly higher in the hypercholesterolemia group, and the total plasma antioxidant status, which was significantly higher in normocholesterolemia subjects. In the case of normocholesterolemia cells in vitro, polyphenols induced a decrease in membrane anisotropy (7.25–11.88% at 24 h, 1.82–2.26% at 48 h) and a hyperpolarizing effect (8.30–8.90% at 24 h and 4.58–13.00% at 48 h). The same effect was induced in hypercholesterolemia cells, but only after 48 h exposure to the polyphenols: the decrease in membrane anisotropy was 5.70% for quercetin and 2.33% for EGCG. After 48 h of in vitro incubation with the polyphenols, PBMCs isolated from hypercholesterolemia patients exhibited the effects that had been registered in cells from normocholesterolemia subjects after 24 h exposure. These results outlined the beneficial action of the studied polyphenols, quercetin and EGCG, as dietary supplements in normocholesterolemia and hypercholesterolemia patients.

Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin produced by the fungi of Fusarium genera. Piglets were fed for 18 days with a control or a ZEN (316 ppb) contaminated diet. At the end of the experiment tissue samples were taken for assessment of: lymphocyte proliferation, monocytes and granulocytes respiratory burst, inflammatory cytokine synthesis in blood and liver, expression of genes involved in oxidative stress or in inflammation, plasma biochemical parameters, total antioxidant status and nitric oxide synthesis. In blood, ZEN increases the respiratory burst of monocytes and the inflammatory cytokine (TNF alpha, IL-1 beta, IFN gamma) synthesis, while in liver, ZEN decreases the synthesis of all inflammatory cytokines investigated. In liver and spleen, different effect on the expression of genes involved in oxidative stress and inflammation was observed. While in liver, ZEN decrease the expression of cyclooxigenase gene, but increase the expression of glutathione peroxydase and catalase genes; in spleen, ZEN induces a decrease of the superoxide dismutase gene expression together with an increase of the cyclooxigenase. In conclusion, our results showed that liver, spleen and blood may also be target tissues in weanling piglets fed ZEN contaminated diet, with different effects on oxidative stress and inflammation.

Quercetin and epigallocatechin gallate are two of the most abundant polyphenols in dietary plants, including apples, onions, red wine and green tea. The bioactivity of polyphenols is linked to their ability to interact with cell membranes without being internalized. The aim of the present study was to assess the short-time effect of these polyphenols on membrane anisotropy and transmembrane potential of U937 monocytes and Jurkat T lymphoblasts. Results showed that quercetin and epigallocatechin gallate induced, after 20 minutes cell exposure, a dose-dependent increase of membrane anisotropy and polarization. Anisotropy increase was correlated with the reduction of lipid peroxidation. Our results could indicate that the antioxidant capacity of the tested polyphenols is due to their stabilizing effect on the cell membranes, thus contributing to cell protection in various pathologies and as adjuvant therapy in highly toxic treatment regimens.

Synthesis of new nucleosides with an oxabiciclo[3.3.0]octane fragment in the sugar moiety was performed by Vorbruggen nucleoside synthesis with silylated pyrimidine bases: 5-FU, 5-ClU, 5-BrU, C and 6-aza-U. The compounds were characterized by IR, MS, 1 H-NMR and 13 C-NMR spectra and tested for their antitumor activity comparatively with U-34 and 5IU-34. Our study points out that Cl-U-34, Br-U-34 and I-U-34 might be more efficient than U-34 against the multiplication of cancer cells, like Jurkat T lymphoblasts.

Zearalenone (ZEN), a mycotoxin produced by several Fusarium spp., is most commonly found as a contaminant in stored grain and has chronic estrogenic effects on mammals. In this in vitro study, we compared the effects of zearalenone (ZEN) and some of its derivatives: α-zearalenol (α-ZOL), β-zearalenol (β-ZOL), and zearalanone (ZAN) on several peripheral blood mononuclear cell (PBMC) parameters: cytotoxicity, proliferation, as well as antibody and cytokine synthesis. The amounts of toxins necessary to inhibit viability, in a dehydrogenase enzyme activity assay (MTT test), by 50% were: 22.7 μM for ZEN, 29.1 μM for α-ZOL, 17.3 μM for β-ZOL and 26.3 μM for ZAN. The administration of 10 μM toxin induced a decrease in the ConA stimulated proliferation of PBMC by 19.6% for ZAN, 45.4% for ZEN, 43.6% for α-ZOL and 85.2% for β-ZOL, when compared to the control stimulated cells. Also, ZEN and its metabolites at concentrations higher than 5 μM induced a significant decrease of the IgG, IgA or IgM levels. Concentrations of 5 and 10 μM of ZEN and ZAN significantly decreased the TNF-α synthesis in the supernatant of the stimulated cells; 10 μM of ZAN also decreased IL-8 synthesis. In conclusion, our results show that ZEN and ZEN derivatives altered several parameters of the humoral and cellular immune response. Therefore, our results are clinically relevant as ZEN and its metabolites are frequent contaminants of animal feed and we have shown that intoxicated animals are incapable of inducing an adequate immune response.

This preliminary study focuses on early peripheral cellular immune changes after 1 month therapy with leflunomide, in 18 patients with severe rheumatoid arthritis, previously treated with methotrexate. A good clinical outcome of disease was documented and we showed that a particular target of short-time leflunomide therapy in rheumatoid arthritis was the peripheral innate immune system (NK cells and the population of granulocytes developing phagocytosis and superoxide anion production when challenged ex vivo with zymosan particles). Meanwhile, the high inter-individual variability of adaptive immunity required data analysis in subgroups of patients. We showed that the abnormal increase of peripheral leukocytes counts, or the decrease towards normal values of the CD4:CD8 lymphocytes ratio, or the inhibition of uridine uptake by ex vivo activated lymphocytes were consistent with a positive clinical evolution, proved by the reduction of tender/swollen joints, morning stiffness duration or acute phase response. We emphasized that significant benefits of short-term leflunomide therapy were associated with functional suppression of peripheral B lymphocytes. Hence, the positive evolution of rheumatoid arthritis patients seemed to be specifically linked to early drug-induced changes of trafficking or uridine metabolism of mononuclear cells.