AI-Driven Optimization of PCL/PEG Electrospun Scaffolds for Enhanced In Vivo Wound Healing.

Here, an artificial intelligence (AI)-based approach was employed to optimize the production of electrospun scaffolds for in vivo wound healing applications. By combining polycaprolactone (PCL) and poly(ethylene glycol) (PEG) in various concentration ratios, dissolved in chloroform (CHCl3) and dimethylformamide (DMF), 125 different polymer combinations were created. From these polymer combinations, electrospun nanofiber meshes were produced and characterized structurally and mechanically via microscopic techniques, including chemical composition and fiber diameter determination. Subsequently, these data were used to train a neural network, creating an AI model to predict the optimal scaffold production solution. Guided by the predictions and experimental outcomes of the AI model, the most promising scaffold for further in vitro analyses was identified. Moreover, we enriched this selected polymer combination by incorporating antibiotics, aiming to develop electrospun nanofiber scaffolds tailored for in vivo wound healing applications. Our study underscores three noteworthy conclusions: (i) the application of AI is pivotal in the fields of material and biomedical sciences, (ii) our methodology provides an effective blueprint for the initial screening of biomedical materials, and (iii) electrospun PCL/PEG antibiotic-bearing scaffolds exhibit outstanding results in promoting neoangiogenesis and facilitating in vivo wound treatment.

Evaluation of novel dendrimer-gold complex nanoparticles for theranostic application in oncology.

Aim: Despite some successful examples of therapeutic nanoparticles reaching clinical stages, there is still a significant need for novel formulations in order to improve the selectivity and efficacy of cancer treatment. Methods: The authors developed two novel dendrimer-gold (Au) complex-based nanoparticles using two different synthesis routes: complexation method (formulation A) and precipitation method (formulation B). Using a biomimetic cancer-on-a-chip model, the authors evaluated the possible cytotoxicity and internalization by colorectal cancer cells of dendrimer-Au complex-based nanoparticles. Results: The results showed promising capabilities of these nanoparticles for selectively targeting cancer cells and delivering drugs, particularly for the formulation A nanoparticles. Conclusion: This work highlights the potential of dendrimer-Au complex-based nanoparticles as a new strategy to improve the targeting of anticancer drugs.

Effects of direct pulp capping with recombinant human erythropoietin and/or mineral trioxide aggregate on inflamed rat dental pulp.

OBJECTIVE: This study aimed to evaluate the dental pulp responses to recombinant human erythropoietin (rhEPO) and/or mineral trioxide aggregate (MTA) in pulp capping of inflamed dental pulp in vivo. MATERIALS AND METHODS: In accordance with ARRIVE guidelines, pulp inflammation was induced by exposing the maxillary first molars (n = 64) of Wistar rats (n = 32) to the oral environment for two days. The exposed pulps were randomly assigned four groups based on the pulp capping material: rhEPO, MTA, MTA + rhEPO, or an inert membrane. An additional eight rats formed the healthy control group. After four weeks, the animals were euthanized, and histological, qRT-PCR, and spectrophotometric techniques were employed to analyze the left maxillary segments, right first maxillary molars, and blood samples, respectively. Statistical significance was set at p < 0.05 and < 0.001. RESULTS: Pulp capping with rhEPO, MTA, or MTA + rhEPO resulted in lower inflammation and higher mineralization scores compared to untreated control. MTA + rhEPO group exhibited significantly decreased expression of tumor necrosis factor-alpha, and interleukin 1-beta, while MTA group showed substantially reduced expression of interferon-gamma. Both rhEPO and MTA + rhEPO groups presented elevated dentin matrix protein 1 levels compared to untreated control. Furthermore, pulp capping with rhEPO and/or MTA led to increased transforming growth factor-beta 1 expression and reductions of pro-inflammatory/immunoregulatory cytokine ratios and prooxidative markers. Pulp capping with rhEPO also resulted in increase of systemic antioxidative stress markers. CONCLUSION: Capping with rhEPO or MTA + rhEPO resulted in a favorable effect that was similar or even superior to that of MTA.

Its all about IFN-λ4: Protective role of IFNL4 polymorphism against COVID-19-related pneumonia in females.

Despite the pivotal role of IFN-λs in the innate immune response, the data on its genetic polymorphism in relation to COVID-19 severity are scarce and contradictory. In the present study, we aimed to determine if the presence of the most frequent functional single nucleotide polymorphisms (SNPs) of the two most important IFN-λs coding genes, namely IFNL3 and IFNL4, alters the likelihood of SARS-CoV-2-infected patients to develop more severe form of the disease. This observational cohort study involved 178 COVID-19 patients hospitalized at the University Clinical Centre Kragujevac, Serbia. Patients' demographics, clinical characteristics, and laboratory parameters were collected at admission. COVID-19 signs and symptoms were assessed during the hospital stay, with the worst condition determining the disease severity. Genotyping for IFNL3 (rs12980275 and rs8099917) and IFNL4 (rs12979860 and rs368234815) SNPs was conducted using TaqMan assays. Our study revealed carriers of IFNL3 and IFNL4 minor alleles to be less likely to progress from mild to moderate COVID-19, that is, to develop COVID-19-related pneumonia. After adjustment for other factors of influence, such as age, sex, and comorbidities, the likelihood of pneumonia development remained significantly associated with IFNL4 polymorphism (odds ratios [ORs] [95% confidence interval (95% CI)]: 0.233 [0.071; 0.761]). When the patients were stratified according to sex, the protective role of IFNL4 minor alleles, controlled for the effect of comorbidities, remained significant only in females (OR [95% CI]: 0.035 [0.003; 0.408]). Our results strongly suggest that IFNL4 rs12979860 and rs368234815 polymorphisms independently predict the risk of COVID-19-related pneumonia development in females.

Combined Biological and Numerical Modeling Approach for Better Understanding of the Cancer Viability and Apoptosis.

Nowadays, biomedicine is a multidisciplinary science that requires a very broad approach to the study and analysis of various phenomena essential for a better understanding of human health. This study deals with the use of numerical simulations to better understand the processes of cancer viability and apoptosis in treatment with commercial chemotherapeutics. Starting from many experiments examining cell viability in real-time, determining the type of cell death and genetic factors that control these processes, a lot of numerical results were obtained. These in vitro test results were used to create a numerical model that gives us a new angle of observation of the proposed problem. Model systems of colon and breast cancer cell lines (HCT-116 and MDA-MB-231), as well as a healthy lung fibroblast cell line (MRC-5), were treated with commercial chemotherapeutics in this study. The results indicate a decrease in viability and the appearance of predominantly late apoptosis in the treatment, a strong correlation between parameters. A mathematical model was created and employed for a better understanding of investigated processes. Such an approach is capable of accurately simulating the behavior of cancer cells and reliably predicting the growth of these cells.

Sacubitril/valsartan reverses cardiac structure and function in experimental model of hypertension-induced hypertrophic cardiomyopathy.

This study evaluated the effect of sacubtril/valsartan on cardiac remodeling, molecular and cellular adaptations in experimental (rat) model of hypertension-induced hypertrophic cardiomyopathy. Thirty Wistar Kyoto rats, 10 healthy (control) and 20 rats with confirmed hypertension-induced hypertrophic cardiomyopathy (HpCM), were used for this study. The HpCM group was further subdivided into untreated and sacubitril/valsartan-treated groups. Myocardial structure and function were assessed using echocardiography, Langendorff's isolated heart experiment, blood sampling and qualitative polymerase chain reaction. Echocardiographic examinations revealed protective effects of sacubitril/valsartan by improving left ventricular internal diameter in systole and diastole and fractional shortening. Additionally, sacubitril/valsartan treatment decreased systolic and diastolic blood pressures in comparison with untreated hypertensive rats. Moreover, sacubitril/valsartan treatment reduced oxidative stress and apoptosis (reduced expression of Bax and Cas9 genes) compared to untreated rats. There was a regular histomorphology of cardiomyocytes, interstitium, and blood vessels in treated rats compared to untreated HpCM rats which expressed hypertrophic cardiomyocytes, with polymorphic nuclei, prominent nucleoli and moderately dilated interstitium. In experimental model of hypertension-induced hypertrophic cardiomyopathy, sacubitril/valsartan treatment led to improved cardiac structure, haemodynamic performance, and reduced oxidative stress and apoptosis. Sacubitril/valsartan thus presents as a potential therapeutic strategy resulted in hypertension-induced hypertrophic cardiomyopathy.

IFNL3/4 polymorphisms as a two-edged sword: An association with COVID-19 outcome.

Coronavirus Disease 2019 (COVID-19) has been ranked among the most fatal infectious diseases worldwide, with host's immune response significantly affecting the prognosis. With an aim to timely predict the most likely outcome of SARS-CoV-2 infection, we investigated the association of IFNL3 and IFNL4 polymorphisms, as well as other potentially relevant factors, with the COVID-19 mortality. This prospective observational case-control study involved 178 COVID-19 patients, hospitalized at Corona Center or Clinic for Infectious Diseases of University Clinical Centre Kragujevac, Serbia, followed up until hospital discharge or in-hospital death. Demographic and clinical data on all participants were retrieved from the electronic medical records, and TaqMan assays were employed in genotyping for IFNL3 and IFNL4 single nucleotide polymorphisms (SNPs), namely rs12980275, rs8099917, rs12979860, and rs368234815. 21.9% and 65.0% of hospitalized and critically ill COVID-19 patients, respectively, died in-hospital. Multivariable logistic regression analysis revealed increased Charlson Comorbidity Index (CCI), N/L, and lactate dehydrogenase (LDH) level to be associated with an increased likelihood of a lethal outcome. Similarly, females and the carriers of at least one variant allele of IFNL3 rs8099917 were almost 36-fold more likely not to survive SARS-CoV-2 infection. On the other hand, the presence of at least one ancestral allele of IFNL4 rs368234815 decreased more than 15-fold the likelihood of mortality from COVID-19. Our results suggest that, in addition to LDH level, N/L ratio, and CCI, IFNL4 rs368234815 and IFNL3 rs8099917 polymorphisms, but also patients' gender, significantly affect the outcome of COVID-19.

Gold(III) Complexes with Phenanthroline-derivatives Ligands Induce Apoptosis in Human Colorectal and Breast Cancer Cell Lines.

Due to their promising effects, gold(III) complexes recently drew increasing attention in the design of new metal-based anticancer therapeutics. Two gold(III) complexes, square-planar [Au(DPP)Cl2]+ - Complex 1 and distorted square-pyramidal [Au(DMP)Cl3] - Complex 2 (where DPP=4,7-diphenyl-1,10-phenanthroline and DMP=2,9-dimethyl-1,10-phenanthroline) were previously synthetized, described and approved as complexes with pronounced cytotoxic effects on colorectal HCT-116 and breast MDA-MB-231 cancer cells. This study investigated the type of cell death by AO/EB double staining, and identification of possible targets responsible for their cytotoxicity, monitored by immunofluorescence and qPCR methods. Both complexes induced apoptosis in all applied concentrations. In the HCT-116 cells apoptosis was activated by external apoptotic pathway, via increase of Fas receptor protein expression and Caspase 8 gene expression. Also, the mitochondrial pathway was triggered by affecting the Bcl-2 members of regulatory proteins and increased caspase 9 protein expression. In MDA-MB-231 cells, apoptosis was initiated from the mitochondria, due to disbalance between expressions of pro- and anti-apoptotic Bcl-2 family members and caspase 9 activation. Complex 1 shows better activity compared to Complex 2, which is in accordance with its structural characteristics. The results deal weighty data about proapoptotic activity of gold(III) complexes and highlighted potential targets for cancer therapy.

Pulpal expression of erythropoietin and erythropoietin receptor after direct pulp capping in rat.

This study aimed to evaluate the effect of direct pulp capping on the expression of erythropoietin (Epo) and Epo-receptor (Epor) genes in relation to the expression of inflammatory and osteogenic genes in rat pulp. Dental pulps of the first maxillary molars of Wistar Albino rats were exposed and capped with either calcium hydroxide or mineral trioxide aggregate, or were left untreated. After 4 wk, animals were euthanized, and maxillae were prepared for histological and real-time polymerase chain reaction analysis. Histological scores of pulp inflammation and mineralization, and relative expressions of Epo, Epor, inflammatory cytokines, and pulp osteogenic genes were evaluated. The capped pulps showed higher expressions of Epo, while the untreated pulps had the highest expression of Epor. Both calcium hydroxide and mineral trioxide aggregate downregulated the expression of tumor necrosis factor alpha compared to untreated controls, and upregulated transforming growth factor beta compared to healthy controls. Alkaline phosphatase expression was significantly higher in experimental groups. Relative expression of Epo negatively correlated with pulp inflammation, and positively correlated with pulp mineralization. Pulp exposure promoted expression of Epor and pro-inflammatory cytokines, while pulp capping promoted expression of Epo, alkaline phosphatase, and downregulated Epor and pro-inflammatory cytokines.

Effects of Combined Allogenic Adipose Stem Cells and Hyperbaric Oxygenation Treatment on Pathogenesis of Osteoarthritis in Knee Joint Induced by Monoiodoacetate.

The beneficial effects of HBO in inflammatory processes make it an attractive type of treatment for chronic arthritis. In addition, the effects of combination therapy based on adipose stem cells and HBO on OA progression have not been fully investigated. The current study explored the efficacy of intra-articular injection of allogeneic adipose-derived mesenchymal stem cells (ADMSCs) combined with hyperbaric oxygenation treatment (HBO) in a rat osteoarthritis (OA) model. The rat OA model was induced by intra-articular injection of monoiodoacetate (MIA) and 7 days after application of MIA rats were divided into five groups: healthy control (CTRL), osteoarthritis (OA), ADMSCs (ADS), the HBO+ADS21day and HBO+ADS28day groups. A single dose of 1 × 106 allogeneic ADMSCs suspended in sterile saline was injected into the knee joint alone or in combination with HBO treatment. Rats were sacrificed at 3 or 4 weeks after MIA injection. Treatment outcomes were evaluated by radiographic, morphological and histological analysis and by specific staining of articular cartilage. We also measured the level of inflammatory and pro/antioxidative markers. We confirmed that combined treatment of ADMSCs and HBO significantly improved the regeneration of cartilage in the knee joint. Rtg score of knee joint damage was significantly decreased in the HBO+ADS21day and HBO+ADS28day groups compared to the OA. However, the positive effect in the HBO+ADS28day group was greater than the HBO+ADS21day group. The articular cartilage was relatively normal in the HBO+ADS28day group, but moderate degeneration was observed in the HBO+ADS21day compared to the OA group. These findings are in line with the histopathological results. A significantly lower level of O2-. was observed in the HBO+ADS28day group but a higher NO level compared to the HBO+ADS21day group. Moreover, in the HBO+ADS28day group significantly higher concentrations of IL-10 were observed but there was no significant difference in proinflammatory cytokine in serum samples. These results indicate that a single intra-articular injection of allogeneic ADMSCs combined with HBO efficiently attenuated OA progression after 28 days with greater therapeutic effect compared to alone ADMSCs or after 3 weeks of combined treatment. Combined treatment might be an effective treatment for OA in humans.

Evaluation of antioxidant and cytotoxic properties of phenolic N-acylhydrazones: structure-activity relationship.

Cancer is still a relentless public health issue. Particularly, colorectal cancer is the third most prevalent cancer in men and the second in women. Moreover, cancer development and growth are associated with various cell disorders, such as oxidative stress and inflammation. The quest for efficient therapeutics is a challenging task, especially when it comes to achieving both cytotoxicity and selectivity. Herein, five series of phenolic N-acylhydrazones were synthesized and evaluated for their antioxidant potency, as well as their influence on HCT-116 and MRC-5 cells viability. Among 40 examined analogues, 20 of them expressed antioxidant activity against the DPPH radical. Furthermore, density functional theory was employed to estimate the antioxidant potency of the selected analogues from the thermodynamical aspect, as well as the preferable free-radical scavenging pathway. Cytotoxicity assay exposed enhanced selectivity of a number of analogues toward cancer cells. The structure-activity analysis revealed the impact of the type and position of the functional groups on both cell viability and selectivity toward cancer cells.

Interrogating and Quantifying In Vitro Cancer Drug Pharmacodynamics via Agent-Based and Bayesian Monte Carlo Modelling.

The effectiveness of chemotherapy in cancer cell regression is often limited by drug resistance, toxicity, and neoplasia heterogeneity. However, due to the significant complexities entailed by the many cancer growth processes, predicting the impact of interference and symmetry-breaking mechanisms is a difficult problem. To quantify and understand more about cancer drug pharmacodynamics, we combine in vitro with in silico cancer models. The anti-proliferative action of selected cytostatics is interrogated on human colorectal and breast adenocarcinoma cells, while an agent-based computational model is employed to reproduce experiments and shed light on the main therapeutic mechanisms of each chemotherapeutic agent. Multiple drug administration scenarios on each cancer cell line are simulated by varying the drug concentration, while a Bayesian-based method for model parameter optimisation is employed. Our proposed procedure of combining in vitro cancer drug screening with an in silico agent-based model successfully reproduces the impact of chemotherapeutic drugs in cancer growth behaviour, while the mechanisms of action of each drug are characterised through model-derived probabilities of cell apoptosis and division. We suggest that our approach could form the basis for the prospective generation of experimentally-derived and model-optimised pharmacological variables towards personalised cancer therapy.

Orally administered fluorescent nanosized polystyrene particles affect cell viability, hormonal and inflammatory profile, and behavior in treated mice.

Commercially manufactured or generated through environmental degradation, microplastics (MPs) and nanoplastics (NPs) considerably contribute to environmental pollution. There is a knowledge gap in how exposure to MPs/NPs changes cellular function and affects animal and human health. Here, we demonstrate that after oral uptake, fluorescent polystyrene (PS) nanoparticles pass through the mouse digestive system, accumulate and aggregate in different organs, and induce functional changes in cells and organs. Using cochlear explant as a novel in vitro system, we confirmed the consequences of PS-MP/NP interaction with inner ear cells by detecting aggregates and hetero-aggregates of PS particles in hair cells. The testes of treated males accumulated MPs/NPs in the interstitial compartment surrounding the seminiferous tubules, which was associated with a statistically significant decrease in testosterone levels. Male mice showed increased secretion of interleukins (IL-12p35 and IL-23) by splenocytes while cyto- and genotoxicity tests indicated impaired cell viability and increased DNA damage in spleen tissue. Males also showed a broad range of anxiogenic responses to PS nanoparticles while hippocampal samples from treated females showed an increased expression of Bax and Nlrp3 genes, indicating a pro-apoptotic/proinflammatory effect of PS treatment. Taken together, induced PS effects are also gender-dependent, and therefore, strongly motivate future research to mitigate the deleterious effects of nanosized plastic particles.

Comparison of Hydroxyapatite/Poly(lactide-co-glycolide) and Hydroxyapatite/Polyethyleneimine Composite Scaffolds in Bone Regeneration of Swine Mandibular Critical Size Defects: In Vivo Study.

Reconstruction of jaw bone defects present a significant problem because of specific aesthetic and functional requirements. Although widely used, the transplantation of standard autograft and allograft materials is still associated with significant constraints. Composite scaffolds, combining advantages of biodegradable polymers with bioceramics, have potential to overcome limitations of standard grafts. Polyethyleneimine could be an interesting novel biocompatible polymer for scaffold construction due to its biocompatibility and chemical structure. To date, there have been no in vivo studies assessing biological properties of hydroxyapatite bioceramics scaffold modified with polyethyleneimine. The aim of this study was to evaluate in vivo effects of composite scaffolds of hydroxyapatite ceramics and poly(lactide-co-glycolide) and novel polyethyleneimine on bone repair in swine's mandibular defects, and to compare them to conventional bone allograft (BioOss). Scaffolds were prepared using the method of polymer foam template in three steps. Pigs, 3 months old, were used and defects were made in the canine, premolar, and molar area of their mandibles. Four months following the surgical procedure, the bone was analyzed using radiological, histological, and gene expression techniques. Hydroxyapatite ceramics/polyethyleneimine composite scaffold demonstrated improved biological behavior compared to conventional allograft in treatment of swine's mandibular defects, in terms of bone density and bone tissue histological characteristics.

Human Embryos, Induced Pluripotent Stem Cells, and Organoids: Models to Assess the Effects of Environmental Plastic Pollution.

For a long time, animal models were used to mimic human biology and diseases. However, animal models are not an ideal solution due to numerous interspecies differences between humans and animals. New technologies, such as human-induced pluripotent stem cells and three-dimensional (3D) cultures such as organoids, represent promising solutions for replacing, refining, and reducing animal models. The capacity of organoids to differentiate, self-organize, and form specific, complex, biologically suitable structures makes them excellent in vitro models of development and disease pathogenesis, as well as drug-screening platforms. Despite significant potential health advantages, further studies and considerable nuances are necessary before their clinical use. This article summarizes the definition of embryoids, gastruloids, and organoids and clarifies their appliance as models for early development, diseases, environmental pollution, drug screening, and bioinformatics.

Synthesis, Characterization and Biological Studies of Organoselenium trans-Palladium(II) Complexes.

BACKGROUND: Over the years, transition metal complexes have exhibited significant antimicrobial and antitumor activity. It all started with cisplatin discovery, but due to the large number of side effects it shows, there is a growing need to find a new metal-based compound with higher selectivity and activity on more tumors. OBJECTIVES: Two novel trans-palladium(II) complexes with organoselenium compounds as ligands, [Pd(L1)2Cl2] (L1 = 5-(phenylselanylmethyl)-dihydrofuran-2(3H)-one) and [Pd(L2)2Cl2] (L2 = 2- methyl-5-(phenylselanylmethyl)- tetrahydrofuran) were synthesized, in the text referred to as Pd-Se1 and Pd-Se2. Also, a structurally similar trans-palladium(II) complex, [Pd(L3)2Cl2] (L3= 2,2- dimethyl-3-(phenylselanylmethyl)-tetrahydro-2H-pyran) was synthesized according to an already published work and is referred to as Pd-Se3. The interaction of synthesized complexes with DNA and bovine serum albumin was observed. Also, antimicrobial activity and in vitro testing, cell viability, and cytotoxic effects of synthesized ligands and complexes on human epithelial colorectal cancer cell line HCT-116 were studied. Molecular docking simulations were performed to understand better the binding modes of the complexes reported in this paper with DNA and BSA, as well as to comprehend their antimicrobial activity. METHODS: The interactions of the synthesized complexes with DNA and bovine serum albumin were done using UV-Vis and emission spectral studies as well as docking studies. Antimicrobial activity was tested by determining the minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) using the resazurin microdilution plate method. Cytotoxic activity on cancer cells was studied by MTT test. RESULTS: The Pd(II) complexes showed a significant binding affinity for calf thymus DNA and bovine serum albumin by UV-Vis and emission spectral studies. The intensity of antimicrobial activity varied with the complexes Pd-Se1 and Pd-Se3, showing significantly higher activity than the corresponding ligand. The most significant activity was shown on Pseudomonas aeruginosa. Under standardized laboratory conditions for in vitro testing, cell viability and cytotoxic effects of synthesized ligands and complexes were studied on human epithelial colorectal cancer cell line HCT-116, where Pd-Se2 showed some significant cytotoxic effects. CONCLUSION: The newly synthesized complexes have the potential to be further investigated as metallodrugs.

Experimental and quantum chemical study оn the DNA/protein binding and the biological activity of a rhodium(iii) complex with 1,2,4-triazole as an inert ligand.

The synthesis and structural characterization of a newly synthesized mononuclear rhodium(iii) complex, Rhtrz, with a ligand (2,2,6-bis((4S,7R)-7,8,8-trimethyl-4,5,6,7-tetrahydro-1H-4,7-methanoindazol-3-yl)pyridine) and a ligand of 1,2,4-triazole, are presented in this paper. The kinetic interactions of the Rhtrz complex with essential biomolecules such as 5-GMP, L-Met, and GSH were examined. The study of the biological interactions was focused on the binding properties of the Rhtrz complex with CT-DNA and serum albumin. These interactions were investigated using UV-vis spectrophotometry, fluorescence spectroscopy, viscosity measurements, thermal denaturation studies, and electrophoresis. Fluorescence competition experiments with site-markers for BSA were used to locate the binding site of the Rhtrz-complex to the BSA. Molecular docking studies were carried out to obtain detailed binding information of the complex with CT-DNA, BSA, and HSA. Furthermore, the apparent distance between the donor (HSA) and acceptor (Rhtrz) was determined using fluorescence resonance energy transfer (FRET). The thermodynamic properties and relative stabilities of the Rhtrz complex were examined, constructing the two model equation by DFT calculations (B3LYP(CPCM)/LANL2DZp). In vitro cytotoxicity and redox status on the human epithelial colorectal cancer cell line (HCT-116) and healthy human fibroblast cell line (MRC-5) were also investigated.

Synthesis, characterization, DFT study, DNA/BSA-binding affinity, and cytotoxicity of some dinuclear and trinuclear gold(III) complexes.

In this study, we have synthesized a series of dinuclear and trinuclear gold(III) complexes of the general formula [Au2(N-N)Cl6] (1-3) for dinuclear and [Au3(N-N)2Cl8]+ (4-6) for trinuclear compounds, respectively, in which N-N is a bidentate ligand (1,4-diaminobutane; 1,6-diaminohexane or 1,8-diaminooctane). These complexes were characterized by elemental analysis, molar conductivity, and spectroscopic techniques (IR, UV-Vis, 1H NMR, ESI-MS). We performed DFT calculations to get insight into the geometry of the studies complexes. DNA-binding studies were performed by UV-Vis spectrophotometry and fluorescence spectroscopy. The results of competitive reactions between gold(III) complexes and ethidium bromide (EB) towards DNA have shown that selected complexes can displace EB from DNA-EB adduct. In addition, these experiments confirm that polynuclear gold(III) complexes interact with DNA covalently or via intercalation. Furthermore, high values of binding constants of gold(III) complexes towards bovine serum albumin (BSA) protein indicate good binding affinity. In addition, redox stability of complexes in the presence of DNA/BSA was confirmed by cyclic voltammetry. Results of the interactions between gold(III) complexes with DNA/BSA were discussed in reference to molecular docking data obtain by Molegro virtual docker. The cytotoxic activity of synthesized gold(III) complexes was evaluated on human breast cancer cell line (MDA-MB-231), human colorectal cancer cell line (HCT-116), and normal human lung fibroblast cell line (MRC-5). All complexes dose-dependently reduced cancer and normal cells viabilities, with significant cytotoxic effects (IC50 < 25 µM) for trinuclear gold(III) complexes (4, 5) on HCT-116 cells.

Synthesis of Camphor-Derived Bis(pyrazolylpyridine) Rhodium(III) Complexes: Structure-Reactivity Relationships and Biological Activity.

Two novel rhodium(III) complexes, namely, [RhIII(X)Cl3] (X = 2 2,6-bis((4 S,7 R)-7,8,8-trimethyl-4,5,6,7-tetrahydro-1 H-4,7-methanoindazol-3-yl)pyridine or 2,6-bis((4 S,7 R)-1,7,8,8-tetramethyl-4,5,6,7-tetrahydro-1 H-4,7-methanoindazol-3-yl)pyridine), were synthesized from camphor derivatives of a bis(pyrazolylpyridine), tridentate nitrogen-donor chelate system, giving [RhIII(H2L*)Cl3] (1a) and [RhIII(Me2L*)Cl3] (1b). A rhodium(III) terpyridine (terpy) ligand complex, [RhIII(terpy)Cl3] (1c), was also synthesized. By single-crystal X-ray analysis, 1b crystallizes in an orthorhombic P212121 system, with two molecules in the asymmetric unit. Tridentate coordination by the N,N,N-donor localizes the central nitrogen atom close to the rhodium(III) center. Compounds 1a and 1b were reactive toward l-methionine (l-Met), guanosine-5'-monophosphate (5'-GMP), and glutathione (GSH), with an order of reactivity of 5'-GMP > GSH > l-Met. The order of reactivity of the RhIII complexes was: 1b> 1a > 1c. The RhIII complexes showed affinity for calf thymus DNA and bovine serum albumin by UV-vis and emission spectral studies. Furthermore, 1b showed significant in vitro cytotoxicity against human epithelial colorectal carcinoma cells. Since the RhIII complexes have similar coordination modes, stability differences were evaluated by density functional theory (DFT) calculations (B3LYP(CPCM)/LANL2DZp). With (H2L*) and (terpy) as model ligands, DFT calculations suggest that both tridentate ligand systems have similar stability. In addition, molecular docking suggests that all test compounds have affinity for the minor groove of DNA, while 1b and 1c have potential for DNA intercalation.