Rapid colorimetric assay for cellular growth and survival: application to proliferation and cytotoxicity assays

Development, in vitro and ex vivo characterization of lamotrigine-loaded bovine serum albumin nanoparticles using QbD approach

The present study aimed to prepare and optimize lamotrigine-loaded bovine serum albumin nanoparticles (LAM-NP) using the Quality by Design (QbD) approach and to investigate both the in vitro and ex vivo effects of different cross-linking agents glutaraldehyde (GLUT), glucose (GLUC) and 1-(3-dimethylaminutesopropyl)-3-ethylcarbodiimide hydrochloride (EDC) on intranasal applicability. Cross-linked LAM-NP from EDC (NP-EDC-1) showed the lowest Z-average value (163.7 ± 1.9 nm) and drug encapsulation efficacy (EE%) of 97.31 ± 0.17%. The drug release of GLUC cross-linked LAM-NP (NP-GLUC-9), glutaraldehyde cross-linked LAM-NP (NP-GLUT-2), and NP-EDC-1 at blood circulation conditions was higher than the initial LAM. The results of the blood-brain barrier parallel artificial membrane permeability assay (BBB-PAMPA) showed an increase in the permeability of LAM through the BBB with NP-GLUC-9 and an increase in flux with all selected formulations. The ex vivo study showed that LAM diffusion from the selected formulations through the human nasal mucosa was higher than in case of initial LAM. The cytotoxicity study indicated that BSA-NP reduced LAM toxicity, and GLUC 9 mM and EDC 1 mg could be alternative cross-linking agents to avoid GLUT 2% v/v toxicity. Furthermore, permeability through Caco-2 cells showed that nasal epithelial transport/absorption of LAM was improved by using BSA-NPs. The use of BSA-NP may be a promising approach to enhance the solubility, permeability through BBB and decrease the frequency of dosing and adverse effects of LAM.

Non-enzymatic electrochemical sensors for point-of-care testing: Current status, challenges, and future prospects

Current electrochemical sensors in point-of-care (POC) testing devices rely mainly on enzyme-based sensors owing to superior sensitivity and selectivity. Nevertheless, the poor stability, high reagent cost, complex fabrication methods and requirement of specific operational conditions make their adaptability in real-world applications unfavorable. Non-enzymatic electrochemical sensors are thus developed as they are more robust and cost-effective strategies. The advancement in material science and nanotechnology enables the development of novel non-enzymatic electrodes with favorable analytical performance. However, the developments are yet far from being adopted as viable products. This review therefore aims to gain insight into the field and evaluate the current progress and challenges to eventually propose future research directions. Here, fabrication strategies based on traditional and emerging technology are discussed in the light of analytical performance and cost-effectiveness. Moreover, the discussion is given on the pros and cons of non-enzymatic sensors when they are employed with various kinds of sample matrices, i.e., clinical and non-clinical samples, which must be taken into consideration for sensor development. Furthermore, molecular imprinting technology in tackling the selectivity issue is introduced and current progress is provided. Finally, the promising strategies from literature for solving the remaining challenges are included which could facilitate further development of robust POC testing devices based non-enzymatic sensors. We believe that once researchers and technology developers have reached the point where most problems are solved, the non-enzymatic sensors are going to be the robust choice for POC testing in clinical diagnostic, ensuring food safety, monitoring contaminants in environment, and bioprocess control.

N,N'-bridged heterocyclic bis-iminium salts as potent antimalarial agents against multi-resistant Plasmodium falciparum

The emergence of Plasmodium resistance to past and newly introduced antimalarial drugs reinforces the need for new antimalarial agents with innovative mechanisms of action. In this regard, the search for new redox-cycling compounds might offer an interesting approach to treat malaria since P. falciparum is sensitive to oxidative stress. Based on our experience in the design of powerful organic reducers, we undertook here the synthesis and evaluation of different families of N-heterocyclic iminium salts that could provide more selective redox-cycling candidates against the K1 multi-resistant Plasmodium falciparum strain (PfK1). Bis-aminopyridinium salts emerged as the most promising candidates, exhibiting nanomolar antiplasmodial activity comparable to that of methylene blue. The biological study also underlined the positive impact on the in vitro activity of electron-donating groups and bis-salt forms, likely due to simultaneous bivalent interactions with the target. Our investigations revealed differences in the mechanism of action according to the heterocycle nature, highlighting an original mechanism for bis-aminopyridinium derivatives, different from that of chloroquine.

Synthetic selenomelanin nanoparticles radio-sensitize non-melanocytic lung cancer (A549) cells by promoting G2/M arrest

Recent studies have postulated the natural existence of selenomelanin and its role in the radio-protection of healthy cells. The present study aimed to understand its radio-modulatory activity in non-melanocytic cancerous (A549) cells of lung origin. Briefly, selenomelanin was synthesized under laboratory conditions following the previously reported methodology. The various spectroscopic (electron paramagnetic resonance, X-ray photoelectron spectroscopy, atomic absorption spectroscopy, transmission electron microscopy and dynamic light scattering) analyses confirmed the formation of selenomelanin nanoparticles. The short-term (72 h) and long-term (14 days) toxicity profiling of selenomelanin by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) and clonogenic assays respectively revealed its half maximal inhibitory concentrations (IC50) of 72.03 ± 7.13 μg/ml and 0.85 ± 0.16 μg/ml respectively in A549 cells and of 81.56 ± 1.63 μg/ml and > 5 μg/ml respectively in healthy lung fibroblast (WI26) cells. Further, pre-treatment of selenomelanin (at concentrations non-toxic for WI26 cells) selectively augmented the radiosensitivity of A549 cells. Finally, mechanistic investigations in A549 cells revealed that selenomelanin increased the levels of reactive oxygen species, DNA damage and modulated the phospho-levels of CHK1 and CHK2 (effectors of cell cycle arrest) in the irradiated cells to favour G2/M arrest followed by cleavage of caspase 3 (effector of apoptosis). Together, the present study proposes the novel application of selenomelanin as a radiosensitizer to enhance the efficacy of radiotherapy in cancerous cells of lung origin.

Nitric oxide-mediated induction of superoxide dismutase and catalase genes, and altered expression of glutathione-dependent genes to defend against the TiO2 NP-induced oxidative stress in primary hepatocytes of air-breathing catfish, Clarias magur

The main objectives of the present investigation were to elucidate the possible induction of antioxidant genes under the TiO2 NP-induced oxidative stress and the potential involvement of endogenously produced nitric oxide (NO) in its antioxidant strategies in primary hepatocytes of air-breathing magur catfish (Clarias magur). As expected, exposure to TiO2 NPs led to (1) more ROS production as evidenced by a sharp rise of hydrogen peroxide (H2O2) and malonaldehyde (MDA) associated with cellular damage as evidenced by the increase of lactate dehydrogenase (LDH) leakage from hepatocytes, (2) induction of superoxide dismutase (SOD), catalase (CAT), followed by induction of different glutathione-related genes such as glutathione peroxidase (GPx), glutathione-S-transferase (GST), and thioredoxin glutathione reductase (TGR) with the induction of activities of corresponding enzymes, and (3) more production of NO associated with induction of inducible nitric oxide synthase (iNOS) activity and its corresponding gene. However, inhibition of NO production in primary hepatocytes using certain inhibitors in the presence of TiO2 NPs, resulted in (1) more generation of H2O2 and MDA, (2) inhibition of SOD and CAT genes expression in primary hepatocytes with more leakage of LDH leakage into the culture media. Thus, it can be contemplated that stimulation NO production plays a vital role in inducing the SOD-CAT system to handle the problems associated with enhanced TiO2 NP-induced ROS production and subsequent oxidative stress in magur catfish as a unique adaptational strategy. However, the NO-mediated induction of glutathione-related antioxidant genes under TiO2 NP-induced oxidative stress is yet to be established.

Discovery and characterization of novel pyridone and furan substituted ligands of choline acetyltransferase

The key to the management of two devastating diseases, namely Alzheimer's Disease (AD) and Amyotrophic Lateral Sclerosis (ALS) lies in an early diagnosis, which is difficult due to its multifactorial nature. However, a common hallmark of AD and ALS is degeneration of cholinergic system. Choline acetyltransferase (ChAT) has been proposed as a potential target for development of cholinergic-specific biomarker. However, lack of selective, potent, brain permeable molecular probes of ChAT hinder development of ChAT biomarkers. In this study, we have successfully utilised structure-based virtual screening approach and identified two ChAT inhibitors from a database of 1.4 million compounds. The compounds were then subjected to rigorous in vitro characterization. Compound V6 showed Ki value of 11 μM and IC50 value of 21.73 μM, while V15 showed Ki and IC50 values of 4.5 and 9.42 μM, respectively for ChAT enzyme. V6 and V15 showed good solubility of 0.21 mg/mL and 0.17 mg/mL respectively and cytotoxicity analysis indicated no toxicity. We also performed a 200 ns molecular dynamics simulation, which revealed the intricate interaction dynamics for V6 and V15 with ChAT binding pocket. Moreover, the Tanimoto similarity analysis indicated the novelty and structural diversity of the hits. In conclusion, these validated hits provide a platform to develop potent, selective, blood-brain barrier permeable small molecules as chemical probes of ChAT or as Positron Emission Tomography tracer for early diagnosis and/or in vivo monitoring of the effect of new therapeutic candidates in spectrum of neurodegenerative disorders, in which cholinergic deficit is one of the hallmarks.

Advanced amphotericin-B gel formulation: An efficient approach to combat cutaneous leishmaniasis

Several drug release studies are continuously carried out to minimize pharmacological limitations, such as insolubility in water and gastrointestinal irritability. This study focused on the development of gels for the administration of amphotericin-B (AmB) for the treatment of cutaneous leishmaniasis. Two gels were prepared from copolymers (polyglycerol and ε-caprolactone) incorporated with AmB. The gels were characterized by FTIR, NMR, TG, and DSC techniques. The incorporation of AmB into the copolymers showed that the medicine remained in the monomeric form, which is the least toxic. The AmB loading presented values of about 31 % (w:w) for TMP-HPG-PCL and for GLY-HPG-PCL, while the encapsulation efficiency was 93 % for both copolymers. According to the release profile, it is observed that, after 48 h, the percentage of AmB released for pure amphotericin, TMP-HPG-PCL-AmB, and GLY-HPG-PCL-AmB were 100 % ± 6 %, 100 % ± 1.5 %, and 47 % ± 13, respectively. Hemolytic study, Cytotoxic Evaluation showed that TMP-HPG-PCL and GLY-HPG-PCL were not toxic to both cell lines (HaCat and MCF-7). These results suggest that the copolymers are safe for in vivo applications being able to act as a drug carrier that have low water solubility corroborating their purpose of polymeric support in the transport of drugs. TMP-HPG-PCL-POL-AmB and for GLY-HPG-PCL-HPG-POL-AmB were used in female mice (BALB/c) infected with Leishmania major foremost for 40 days, and it was found that in animals treated with the gel/copolymer/AmB, there was a reduction in the number of parasites of around 70 %. Histopathological studies showed the presence of small intralobular granulomas and moderate Kupffer cell hypertrophy/hyperplasia. The results show that the TMP-HPG-PCL-POL-AmB and for GLY-HPG-PCL-HPG-POL-AmB efficiently combats cutaneous leishmaniasis.

Secosteroid - 1,3,4-oxadiazole hybrids: Synthesis and evaluation of their activity against hormone-dependent breast cancer cells

This study focused on the synthesis of secosteroids with good antiproliferative properties against hormone-dependent breast cancer. A straightforward and efficient method for synthesizing secosteroid - 1,3,4-oxadiazole hybrids was developed starting from 13α-hydroxy-3-methoxy-13,17-secoestra-1,3,5(10)-trien-17-oic acid hydrazide. The cyclization of hydrazide moiety with CS2 into 1,3,4-oxadiazole-2(3H)-thione fragment followed by sulfur alkylation resulted in the formation of various secosteroid - 2-mercapto-1,3,4-oxadiazole hybrids. These novel compounds were evaluated for their antiproliferative activity against the hormone-dependent human breast cancer cell line MCF-7. Among the synthesized hybrids, compounds 3i, 3o, and 3q displayed notable antiproliferative effects, with IC50 values ranging from 6.5 to 8.9 µM, comparable to the reference drug cisplatin. Furthermore, compound 3i showed minimal toxicity toward non-cancerous hFB-hTERT fibroblasts, indicating high selectivity. Compounds 3o and 3q exhibited antiestrogenic activity. Additionally, their effects on PARP and Bcl-2 suggest a pro-apoptotic mechanism of action. These findings highlight the potential of secosteroidal hybrids as promising candidates for the development of new anti-breast cancer agents targeting ERα and apoptosis pathways.

Mutagenic assessment and toxicological impact of bergenin in a phenolic-enriched extract from Endopleura uchi (Huber) Cuatrec bark, a medicinal plant from the Amazon rainforest

Endopleura uchi bark traditionally used in folk medicine attributed to its anti-inflammatory properties is due to the presence of bergenin. This study aimed to determine the toxicological parameters associated with exposure to a phenolic-enriched extract of E. uchi bark and bergenin a bioactive byproduct of this compound. The total phenolic and flavonoid contents were determined through spectrometric analyses, while phenolic compounds were identified using ultra-performance liquid chromatography coupled with high-resolution mass spectrometry (UPLC-MS). Antioxidant activity was assessed in vitro using the DPPH assay. Cytotoxicity and genotoxicity were assessed via the MTT assay and comet assay, respectively, whereas mutagenic activity was examined using Salmonella/microsome assay and micronucleus (MN) test. A high content of phenolic (732.22 ± 9.48 mg/g) GAE (gallic acid equivalence) and flavonoid 252.47 ± 5.7 mg/g QE (quercetin) compounds was found in bergenin the phenolic-enriched extract byproduct as well as isomers of gallic acid, epicatechin, isoquercitrin, castalagin, punicalin, and punicalagin. The DPPH value was 23.74 ± 0.45 μg/ml. In MTT assay, the extract exhibited an IC50 of 72.5 ± 2.6 µg/ml. Both extract and bergenin displayed genotoxic activity in L929 fibroblast cells at 50 µg/ml but not mutagenic effects in the Salmonella/microsome assay or MN test. Despite the genotoxic actions, E. uchi bark and bergenin extract did not induce gene or chromosomal mutations, suggesting a low risk of compromising genomic stability. The presence of bioactive compounds such as bergenin and punicalagin in E. uchi bark demonstrates a therapeutic potential of this native tree for treating inflammatory diseases.

New acetamide-sulfonamide scaffolds with potential renal radiomodulatory effects: Insights into NF-κB pathway interactions

With the increased use of radiation in cancer therapy, new effective antioxidants and anti-inflammatory agents are required to alleviate the negative impact caused by irradiation. A set of novel N-substituted-2-((2-oxo-2-((4-sulfamoylphenyl)amino)ethyl)thio) acetamide derivatives 3-14 was synthesized to act as possible radiation mitigators. The synthesized compounds were screened for their anti-inflammatory and antioxidant potential using selective COX-2 inhibitory activity and DPPH assays compared to celecoxib and ascorbic acid, respectively. Compound 9 was the most active in this series with selective COX-2 inhibitory activity (IC50 = 0.373 μM), and free radical scavenging properties (IC50 = 4.89 μM). In vitro and in vivo studies demonstrated that compound 9 exhibited a high safety profile, with low cytotoxicity on normal cells (IC50 > 800 μM) and a median lethal dose (LD50) of 300 mg/kg. The potential renal radiomodulatory effect of the promising candidate was investigated in mice exposed to gamma radiation (6 Gy). Compound 9 successfully reduced radiation-induced oxidative stress, as seen by lower levels of reactive oxygen species (ROS), malondialdehyde (MDA), and enhancement in the levels of reduced Glutathione (GSH) in kidney tissues. Moreover, compound 9 reduced kidney inflammatory markers; Nuclear factor kappa B (NF-κB) and Interleukin 6 (IL-6) in irradiated mice, while lowering serum urea and creatinine levels relative to untreated irradiated group. Compound 9 additionally modified the histological alterations caused by gamma irradiation-induced tubular epithelial cell necrosis. Accordingly, compound 9 can help to reduce the adverse effects of irradiation.

Synthesis, structure activity relationship and biological evaluation of indole sulfonohydrazide derivatives as antagonists of P2Y1 and P2Y6 receptors

The P2Y receptors play a significant role in regulating various physiological functions, such as neurotransmission and inflammatory response. They are also considered promising therapeutic targets for the treatment and prevention of conditions like neurological disorders, pain, cardiovascular diseases, thrombosis, and cancer. Active research is ongoing to identify antagonists of P2Y receptor. Although extensive research has been conducted on P2Y receptors inhibitors, only a limited number of P2Y receptors antagonists have been identified and approved by regulatory authority. In the current research, new indole sulfonohydrazide derivatives (3a-3 k) were synthesized in good yield. Based on toxicity assays performed on h-1321 N1 astrocytoma cell line, these low molecular weight compound showed a safe toxicity profile. The synthesized derivatives were also screened against tP2Y1 and rP2Y6 receptors using a calcium mobilization assay. The results showed that compounds 3a, 3b, 3 h and 3 k were potent against tP2Y1 with IC50 values of 9.91 ± 1.01 μM, 3.49 ± 0.31 μM, 9.72 ± 0.82 μM, and 6.14 ± 0.17 μM, respectively. Additionally, three compounds, i.e., 3d, 3f, and 3 h, exhibited potency against rP2Y6 with IC50 value of 9.22 ± 1.10 μM, 16.25 ± 0.27 μM, and 1.89 ± 0.11 μM, respectively. Molecular docking study was conducted to support the in vitro analysis, which revealed that the tested compounds showed favorable interaction with the amino acids of the target P2Y1 receptor, including Phe62, Phe66, Leu102, Thr103, Pro105, Ala106, Phe119 and Met123. An in silico pharmacokinetic study was also performed, which revealed that the synthesized compounds met all the criteria for favorable gastrointestinal absorption, indicating potential for oral bioavailability. The stability and reactivity of compounds were determined by using the Guassian09 programme in which the density functional theory (DFT) calculations were performed by using the B3LYP/SVP level.

Novel chloropyridazine sulfonamides as aromatase inhibitors and apoptotic inducers in breast cancer

Aromatase catalyzes the rate-limiting and final step in the biosynthesis of estrogen. Inhibitors of this enzyme are effective targeted therapy for breast cancer. Molecular hybridization is a promising strategy in drug discovery that combines two or more biologically active moieties in a single structure. In this work, we aim at combining sulfonamide, chloropyridazine and pyrrole in a single design as potential aromatase inhibitors for breast cancer. The synthesized compounds were subjected to in vitro cytotoxic screening against MCF-7 breast cancer cell line, then were assessed for their ability to inhibit aromatase enzyme. Compound 10 exhibited a promising cytotoxic activity (IC50 1.83 μM) that nearly equal to the reference drug (doxorubicin, IC50 1.94 μM) on MCF-7 cells. Also, compound 10 was the most potent aromatase inhibitor with the lowest IC50 (0.06 μM) compared to letrozole (IC50 0.05 μM). Based on the promising results of compound 10, it was selected to investigate its apoptotic effect that disclosed a marked increase in Bax level to 5.42 folds and down-regulation in Bcl-2 expression to 0.34 folds in MCF-7 cells compared to letrozole. Moreover, compound 10 increased caspase 9 level by 4.84 folds. Also, compound 10 arrested the cell cycle at G1 phase and caused induction of early and late apoptosis in an AnnexinV-FITC assay. Compound 10 had been evaluated to study its synergistic effect with γ-radiation by evaluating the cytotoxicity against MCF-7 after exposure to gamma rays (8 Gy). In addition, compound 10 showed low toxicity against human normal breast (MCF-10 A) cell line. Docking study of compound 10 was performed and showed binding with the key amino acids in aromatase active site.

The development of pyridazinone-based andrographolide derivatives as anti-cancer agents with the ability of inhibiting the TFAP4/Wnt/β-catenin signaling pathway

Emerging evidence indicated that natural andrographolide and its derived compounds could exert anti-cancer effects on a broad range of cancer cells by several mechanisms of actions. However, the potent andrographolide derivatives with novel structures are needed and the comprehensive understanding of the underlying mechanisms of actions are still lacking. In this work, we reported the pyridazinone-based anti-cancer andrographolide derivative A61, which is superior to the widely-used anti-cancer drug 5-FU (around 5-fold more potent), it showed high potency to inhibit the growth and migration of a panel of cancer cells, in which the gastric cancer cells exhibited the highest drug sensitivity. Preliminary anti-cancer mechanistic studies indicated that A61 exerted its anti-gastric cancer effect by inducing cell apoptosis through intrinsic mitochondria-mediated pathways and arresting cell circle at S phase. Further exploration at the molecular level indicated that compound A61 may inhibit the transcriptional activity and nuclear localization of TFAP4 in gastric cancer cells by inhibiting the TFAP4/Wnt/β-catenin signaling pathway. For the first time, the TFAP4/Wnt/β-catenin signaling pathway was found to be responsible for the anti-cancer activity of andrographolide derivative. In addition, A61 was demonstrated to have significantly increased bioavailability in rats compared with andrographolide. This work provides pertinent information for the understanding of the anti-cancer mechanism by this class of compounds.

Genotoxicity of putrescine and its effects on gene expression in HepG2 cell line

Decomposing bodies release necro-leachate, a toxic fluid containing harmful compounds such as biogenic amines. This study investigated the genotoxic effects of the different concentrations (0.5, 1.4, 2.3, 3.2 mM) of bioamine putrescine on HepG2 cells using the comet assay, the micronucleus test, and gene expression analysis. The results were compared to negative control and indicated significant DNA damage in the comet assay highlighting tail DNA intensity that exhibited significant differences across all tested concentrations (0.5 = 192 %, 1.4 = 189 %, 2.3 = 208 %, 3.2 = 132 %). The micronucleus test revealed a significant increase in micronuclei for concentrations 0.5 (193 %), 1.4 (229 %), 2.3 (206 %); nuclear buds 3.2 (173 %); chromosomal bridges 3.2 (735 %). Furthermore, genes linked to oxidative stress and DNA damage exhibited statistically significant expression alterations. These findings suggest that putrescine has genotoxic potential in human-derived HepG2 cells, raising concerns about cemetery contaminants' occupational and environmental risks. This study is the first to assess putrescine's toxicity as an environmental pollutant, as previous research has mainly focused on its role in the food sector. These insights highlight the potential threats necro-leachate poses to environmental health, emphasizing the need for further research on cemetery pollution.

In vitro and in vivo attenuation of Salmonella resistance using a novel synthesized chloramphenicol magnesium Nano-complex

In this study, Chloramphenicol-Mg-Nano-complex (CHL-Mg-NC) was synthesized as a novel antimicrobial agent to attenuate chloramphenicol resistant Salmonella clinical isolates in vitro and in vivo. The CHL-Mg-NC was prepared in presence of gamma radiation and validated by SEM, DLS, Zeta potential, and FTIR, that revealed typical CHL-Mg-NC characteristics. The Phenotypes, biochemical investigations and molecular identification assays defined Salmonella isolates and further detection of invA gene in S. Paratyphi A NCRR-CHR1, S. Enteritidis NCRR-CHR2 and S. Typhimurium NCRR-CHR3 were appraised. In vitro anti-Salmonella efficacy of CHL-Mg-NC was assessed against Salmonella isolates in addition to Typhimurium ATCC 700720. Gamma radiation improved CHL-Mg-NC synthesis in dose-depend manner up to 5 kGy. CHL-Mg-NC showed MIC at a range from 0.156 to 0.625 μg/mL and MBC from 0.3125 to 2.5 μg/mL with MBC/MIC ratio less than or equal to 4. CHL-Mg-NC inhibited biofilm formation in the range of 45.31 %-100 %. It also had bactericidal activity at 2MIC within the low time ranged from 2h to 4h. The in vivo efficacy of CHL-Mg-NC was observed by the reduction in the number of viable Salmonella recovered from feces in infected mice and showed evident improvement in CHL-Mg-NC treated groups.CHL-Mg-NC has no significant cytotoxic effects on normal cells and CC50 is 13.5 μg/mL against CACO2 cells. Acute toxicity of CHL-Mg-NC indicates that the CHL-Mg-NC is safe at high concentrations.

Gracilaria edulis-mediated silver nanoparticles as a targeted strategy for cervical cancer with integrated toxicity evaluation in zebrafish

Cervical cancer remains a critical global health concern, demanding the development of innovative therapies to address the limitations of conventional chemotherapeutics, including systemic toxicity and lack of specificity. Silver nanoparticles synthesized using Gracilaria edulis (GE-AgNPs) present a novel therapeutic strategy, exhibiting selective cytotoxicity against the HEK293 normal epithelial cell line and HeLa cervical cancer cell line. Phytochemical analysis of Gracilaria edulis identified bioactive compounds such as 4-Benzaldehyde and 1H-1,3-Benzimidazole-1-acetonitrile, both associated with potent anticancer activities. Comprehensive characterization of GE-AgNPs through spectroscopy and microscopy revealed distinctive physicochemical properties, including an absorption peak at 332 nm and a hexagonal crystalline structure. Cytotoxicity assays confirmed that GE-AgNPs induce apoptosis in HeLa cells exhibit a concentration-dependent response, with an IC50 value of 54.05 μg/mL, while GE-AgNPs exhibited no significant toxicity to HEK293 cells at the tested concentrations, as evidenced by a higher IC50 value of 83.6 μg/mL. The pro-apoptotic effect was mediated through the development of reactive oxygen species (ROS), validated using dual staining and Hoechst assays, which demonstrated chromatin condensation indicative of apoptosis. Molecular analysis further elucidated the mechanism of action, highlighting significant inhibition of the PI3K/AKT signaling pathway. This was evidenced by downregulation of PI3K, AKT, and mTOR genes alongside the upregulation of PTEN, a critical tumor suppressor. Zebrafish embryo toxicity assays provided insights into the biocompatibility of GE-AgNPs, revealing low toxicity at therapeutic concentrations but developmental abnormalities and neurotoxicity at higher doses. These findings underscore the promise of GE-AgNPs as a targeted therapy option for cervical cancer, effectively modulating the PI3K/AKT pathway while maintaining manageable toxicity profiles. Further investigations into optimizing dosing regimens and exploring synergistic effects with existing treatments could enhance their clinical applicability.

Ouabain increases neuronal differentiation of hippocampal neural precursor cells

Image 1.

Prolonged exposure to simvastatin affects coenzyme Q9/10 status leading to impaired mitochondrial respiratory capacity and reduced viability of cultured cardiac cells

This study investigates the effects of prolonged simvastatin exposure on coenzyme Q9/10 (CoQ9/10) levels, an essential component of antioxidant defense, in cultured cardiac cells. Statins, commonly used to manage dyslipidemia and reduce cardiovascular risk, may impair mitochondrial function, but their impact on CoQ10 depletion and oxidative stress is not well understood. We examined the influence of simvastatin on mitochondrial oxidative capacity, reactive oxygen species (ROS) production, and CoQ9/10 status at concentrations of 0.3, 0.6, 1.25, 2.5, 5, 10, and 20 μM, over durations of 24, 48, and 72 h. Using an in vitro model of cultured H9c2 cardiomyoblasts, our results showed that short-term exposure (24 h) at lower concentrations (<5 μM) enhanced cytosolic and mitochondrial ROS levels without affecting mitochondrial function or CoQ9/10 status. However, prolonged exposure to higher concentrations (≥10 μM for >48 h) resulted in impaired mitochondrial oxidative capacity, indicated by increased proton leak and elevated ROS levels, which were followed by significantly reduced cell viability. These findings suggest that prolonged, high-dose simvastatin exposure may disrupt the oxidative balance of CoQ9/10, leading to myocardial injury. This research addresses a gap in understanding the long-term effects of statins on mitochondrial health and underscores the need for further studies to optimize statin therapy and minimize adverse effects on myocardial function.

Heterodimeric vipoxin and its individual monomeric subunits display a dynamic structure-function relationship on RPE cells

Known as some of the most toxic venom components, snake venom Phospholipases A2 (svPLA2) impress with their great arsenal of activities, based on catalytic specificity and a variety of non-catalytic "pharmacological" effects using complex molecular mechanisms that can affect different tissues and organs. Here, we aim to reveal the role of the intricate interactions between the monomeric subunits of the heterodimeric neurotoxic complex vipoxin in order to perform multiple differentiated and regulated biological activities in RPE cells. Vipoxin, isolated from the venom of Vipera ammodytes ssp. meridionalis, is composed of a basic and toxic secreted PLA2 enzyme subunit (GIIA sPLA2, vipoxin basic component, VBC) and an acidic, enzymatically inactive and non-toxic subunit (vipoxin acidic component, VAC). We established that vipoxin and its separated monomeric subunits affect integrity and viability of the cells of two RPE lines using a combination of catalytic and non-catalyticmechanisms. Individual monomeric subunits VBC and VAC induce cytotoxicity, cytoskeletal rearrangements, affect transepithelial resistance and cell monolayer integrity, trigger apoptosis, p38 MAPK signaling pathway and genotoxicity, provoking very elaborate cellular response in both cell lines. VBC uses its catalytic and pharmacological activities more pronounced in RPE-1 than in ARPE-19 cell line, triggering DNA double-strand damage as well as a higher degree of cytotoxicity (up to 45 %) in a concentration-dependent manner. In contrast, the non-catalyticVAC exhibited insignificant effect on the membrane integrity of both RPE cell lines but induced very high degree of DNA damage in ARPE-19 cells. Heterodimeric vipoxin displaced its complex and dynamic biological efficiency in both cell lines. In general, all the investigated activities of vipoxin and its individual monomeric subunits proved our assumption for the existence of complex dynamic conformational and structural interactions between the subunits providing an immediate selection of the enzymatic or "pharmacological" mode of action, strongly dependent on RPE cell membrane composition and their microenvironment.

Antifungal and antibiofilm activity of Lippia microphylla Cham. essential oil. (Verbenaceae) on Candida albicans and human cell cytotoxicity

OBJECTIVE

This study evaluated the antifungal activity of Lippia microphylla essential oil (LM-EO) on Candida albicans.

DESIGN

In vitro assays were conducted to test LM-EO for its anti-Candida effects, antibiofilm activity, effects on the fluorescence intensity of Candida albicans biofilms observed via confocal microscopy, probable mechanism of action, and toxicity on human keratinocytes. Statistical analysis was performed considering α = 5 %.

RESULTS

The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of LM-EO ranged from 128 µg/mL to 256 µg/mL and 256 µg/mL to 1024 µg/mL, respectively. MIC values did not change in the presence of sorbitol, whereas a 4-fold increase was observed in the presence of ergosterol, suggesting that LM-EO may act on the cell membrane. This was subsequently observed via confocal microscopy using propidium iodide markers. LM-EO reduced biofilm adherence by 66-86 % (p < 0.0001) at low concentrations (256-2560 µg/mL); however, it showed toxicity in human cells.

CONCLUSIONS

LM-EO exhibited fungicidal activity likely through a mechanism related to ergosterol complexation but demonstrated cytotoxicity to human keratinocytes.

Glyphosate-based herbicide as a potential risk factor for breast cancer

Breast cancer is the most common neoplasm in women worldwide, with both genetic and environmental factors playing a role in its development. Glyphosate, the active ingredient in widely used agricultural herbicides, is recognized as a potential carcinogen and endocrine disruptor, making it a candidate for inducing epigenetic modifications linked to breast cancer. This study investigates the effects of the glyphosate-based herbicide Roundup® on non-tumorigenic (MCF10A) and tumorigenic (MCF7 and MDA-MB-231) breast cell lines, focusing on the expression of key breast cancer-related genes. Additionally, the study examines the association with epigenetic modifications and the use of epidrugs to reverse potential alterations, aiming to understand the risks and mechanisms of herbicide action. Results indicate that Roundup® affects cells through a non-estrogenic mechanism, impacting both hormone-dependent and -independent cells with varying toxic and proliferative effects depending on dose and exposure time. Moreover, it altered the expression of breast cancer-related genes such as BRCA1 and BRCA2 at low doses. The use of epigenetic modulators was able to reverse some Roundup®-induced changes, suggesting the herbicide's role in epigenetic modifications. Overall, these findings highlight the importance of understanding glyphosate-based herbicide mechanisms in humans, which could enable personalized prevention strategies to mitigate breast cancer risks.

Exploring Thieno/Furo[2,3-b]pyridines as new scaffolds for potential FAK inhibition: Design, synthesis, biological evaluation and in silico studies

Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that plays a vital role in regulating cancer cell survival, proliferation, migration, and angiogenesis. Aiming to explore new potent inhibitors, a series of thieno/furo[2,3-b]pyridine derivatives was designed and synthesized. The newly synthesized compounds were evaluated for their in vitro anti-proliferative activity against human liver (HUH-7), lung (A549) and breast (MCF-7) cancer cell lines, in addition to their cytotoxic activity against normal lung cell line (WI-38) to predict their safety profile. Seven compounds (4a, 4c, 5, 6, 10c, 11 and 12) displayed significant anti-proliferative activity as well as high selectivity towards the tested cancer cell lines (SI > 2). Among them, two compounds (4a and 4c) potently inhibited FAK enzyme with IC50 values of 54.96 and 50.98 nM, respectively. Flow cytometric cell cycle analysis indicated that compounds 4a and 4c caused cell cycle arrest at G1 phase. Compound 4c also exhibited an increase in the expression level of caspase-3 enzyme. Moreover, molecular docking study of the most promising compounds into FAK's active site was performed to elucidate their possible binding modes and to provide a structural basis for the further structural guidance design of FAK inhibitors.

In vitro investigation of the toxicological mechanisms of Fingolimod (S)-phosphate in HEPG2 cells

Fingolimod (FTY720) was the first sphingosine-1-phosphate (S1P) receptor modulator approved by the US Food and Drug Administration for the treatment of multiple sclerosis. The active form, FTY720 (S)-P, acts as a potent agonist of the S1P receptor, leading to its downregulation on the cell surface, reduced activity, and termination of sphingosine-dependent intracellular signalling. Elevated hepatic enzyme levels, clinically significant liver injury, and acute liver failure have been observed in patients treated with FTY720 (S)-P, which requires additional monitoring. This is the first study to investigate the mechanisms underlying the hepatotoxicity of FTY720 (S)-P and represents an important contribution to elucidating its toxicity mechanisms in the human hepatocellular carcinoma cell line HepG2. Following a 72-h exposure, standard methods were used to evaluate specific targets, including cytotoxic effect potentials, mitochondrial parameters, and changes of the antioxidant enzyme levels. FTY720 (S)-P exposure resulted in time- and dose-dependent decreases in cell viability, mitochondrial membrane potential, and ATP levels, as well as the induction of oxidative stress. The complex toxic profile observed for FTY720 (S)-P is hypothesized to originate from its interaction with sirtuin proteins, particularly SIRT3 and SIRT5. It was also complemented with molecular docking simulations to assess the compound's targeting potential by analysing its interaction profile and binding pose within the active sites of both proteins. The results supported the proposed hypothesis, demonstrating an optimal fitting profile and favourable interaction behaviour within the binding pockets of the SIRT3 and SIRT5 enzymes.

Antifungal, Antimycobacterial, Protease and α‒Amylase Inhibitory Activities of a Novel Serine Bifunctional Protease Inhibitor from Adenanthera pavonina L. Seeds

Antifungal resistance poses a significant challenge to disease management, necessitating the development of novel drugs. Antimicrobial peptides offer potential solutions. This study focused on extraction and characterization of peptides from Adenanthera pavonina seeds with activity against Candida species, Mycobacterium tuberculosis, proteases, and α-amylases. Peptides were extracted in phosphate buffer and heated at 90°C for 10 min to create a peptide rich heated fraction (PRHF). After confirming antimicrobial activity and the presence of peptides, the PRHF underwent ion exchange chromatography, yielding retained and non-retained fractions. These fractions were evaluated for antimicrobial activity and cytotoxicity against murine macrophages. The least toxic and most active fraction underwent reversed-phase chromatography, resulting in ten fractions. These fractions were tested for peptides and antimicrobial activity. The most active fraction was rechromatographed on a reversed-phase column, resulting in two fractions that were assessed for antimicrobial activity. The most active fraction revealed a single band of approximately 6 kDa and was tested for inhibitory effects on proteases and α-amylases. Thermal stability experiments were conducted on the 6 kDa peptide at different temperatures followed by reassessment of antifungal activity and circular dichroism. The 6 kDa peptide inhibited yeasts, M. tuberculosis, human salivary and Tenebrio molitor larvae intestine α-amylases, and proteolytic activity from fungal extracts, and thus named ApPI. Remarkably, ApPI retained antifungal activity and conformation after heating and is primarily composed of α-helices. ApPI is a thermally stable serine protease/α-amylase inhibitor from A. pavonina seeds, offering promise as a foundational molecule for innovative therapeutic agents against fungal infections and tuberculosis.

Comparative Assessment of colorimetric assays in evaluating intracellular drug susceptibility of Leishmania tropica against conventional antileishmanial drugs

This study aims to identify the most sensitive colorimetric test for assessing intracellular drug susceptibility of Leishmania tropica to conventional antileishmanial drugs. To this end, the efficacy of four colorimetric methods-MTT, XTT, MTS, and WST-8-was compared using reference L. tropica promastigotes. The intracellular drug susceptibility was further evaluated using the test with the widest absorbance range on isolates from Türkiye CL patients: two responsive to a single course of meglumine antimoniate (MA) and two that showed no clinical improvement after two treatments. CL isolates were identified via real-time PCR targeting the ITS1 region. Promastigote suspensions at standardized densities (0.08 × 106 to 10 × 106 promastigotes/well) were prepared in both RPMI (phenol red-containing) and RPMIØRP (phenol red-free) media, then analyzed with ELISA-based MTT, XTT, MTS, and WST-8 to identify the method with the broadest specific absorbance range. Intracellular drug susceptibility of CL isolates was subsequently assessed in a macrophage/amastigote model by infecting THP-1 macrophages with promastigotes from both reference and patient isolates, followed by treatment with MA, sodium stibogluconate (SSG), miltefosine (MTF), pentamidine (PMD), and amphotericin B (AmB). Promastigotes obtained from parasite rescue and transformation assays were analyzed using the most sensitive colorimetric method to determine IC₅₀ values. Species identification confirmed all four CL isolates as L. tropica, and the XTT assay provided the widest absorbance range in RPMIØRP media. IC₅₀ values for both treatment-responsive and unresponsive isolates were similar to those of the reference isolate, showing susceptibility to all tested drugs without statistically significant differences. Expanding the isolate set is necessary to further evaluate the predictive value of SbV (pentavalent antimonials) susceptibility for treatment outcomes. The identification of XTT as the most sensitive method for intracellular antileishmanial susceptibility testing is expected to aid in standardizing laboratory models and provide valuable insights for researchers and clinicians managing treatment-unresponsive CL cases.

Ultrasound-assisted green synthesis of silver nanoparticles using Ruta graveolens L. Extract and antitumor evaluation

This study aims to evaluate the ultrasound-assisted synthesis of silver nanoparticles (AgNPs) based on an aqueous extract of Ruta graveolens L. to reduce Ag+ to Ag0. In addition, the biological activity of the synthesized AgNPs was evaluated against tumor cells. The following parameters were evaluated for the synthesis: proportion between Ag+ solution (0.1 mol L-1 Ag+) and R. graveolens L. extract, pH of R. graveolens L. extract (5, 7, and 9), temperature of solution containing Ag+ and R. graveolens L. extract, ultrasound (US) type (bath and probes), and the parameters for US as frequency (37, and 80 kHz for bath and 20 kHz for probes), amplitude and time of application of US. In order to confirm the US effect, "silent" experiments (without US) were performed. Using the optimized conditions (US bath, proportion between Ag+ solution and R. graveolens L. of 1 + 5, v v-1, 80 kHz, 70 % amplitude, 70 °C, pH 9, and 25 min of sonication time) it was possible to obtain mean size, PI, and zeta potential of AgNPs of 30 nm, 0.129, -34.44 mV, respectively. For comparison of results, AgNPs synthesized in the "silent" condition presented mean size, PI, and zeta potential of 66 nm, 0.412, and -22.12 mV, respectively. The US synthesized AgNPs were lower, more uniform, and stable when compared with magnetic stirring. In addition, the morphology of AgNPs using US was predominantly spherical and monodisperse. The biological activity using cell lines HaCat (keratinocytes), L929 (fibroblasts), and B16-F10 (melanoma) against nanoparticles synthesized using US was evaluated against the different cell lines and the antioxidant activity of the AgNPs was measured by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. A higher cytotoxic effect on the melanoma cell line (IC50 = 2.12 µg mL-1) compared to normal cells. A good result was found in the DPPH assay, with an IC50 of 234.3 µg mL-1 for free radical scavenging. Therefore, the US technology presents a promising and sustainable green method avoiding the use of toxic reagents and obtained AgNPs showed potent anticancer activity.

Evaluating dermal toxicity of the flame retardant aluminum diethylphosphinate by in silico-in vitro testing strategy

Flame retardants (FRs) are a group of chemicals used in different products to improve fire safety; however, many of them negatively impact human health, encouraging the use of safer alternatives. The aluminum diethylphosphinate (AlPi) is one of the potential alternatives to harmful FRs; however, close data gaps on human toxicity and enhanced mechanistic understanding are still needed. This study evaluated the dermal toxicity potential of AlPi using in silico models (OECD QSAR Toolbox, Toxtree) and a multi-biomarkers approach with human keratinocyte models (HaCaT cell line and reconstructed human epidermis (RHE) model). Our findings revealed no significant increases in reactive oxygen species (ROS, H2DCFDA) or pro-inflammatory cytokines (IL-6, IL-8, IL-10, IL-1β, IL12p70, TNF) in HaCaT cells exposed to AlPi at non-cytotoxic concentrations (30, 60, 120 μg/ml). This suggests that AlPi does not induce oxidative stress or inflammatory responses in the skin. Additionally, in silico predictions and in vitro assays (HaCaT - IL-6; OECD TG 439 with SkinVitro-RHE) did not classify AlPi as a skin sensitizer or skin irritant. Regarding changes in DNA, AlPi-exposed HaCaT cells did not show significant levels of γ-H2AX; however, this FR increased the level of 5-hydroxymethylcytosine (5-hmC) and TET1 expression, which is a gene involved in the regulation of the DNA methylation. In summary, most biomarker responses indicated that AlPi poses minimal toxic effects on the skin; however, further research is needed to understand better the biological consequences of its effect on DNA methylation.

New pyrrolo[3,4-d] isoxazolidines hybrid with furan as antitumor agents and multi-target enzyme inhibitors: Synthesis and in silico study

Herein, new Pyrrolo[3,4-d] isoxazolidines hybrid with furan were synthesized by 1,3-dipolar cycloaddition reaction of nitrone 2 with N-substituted maleimides 3a-j. The synthesized compounds were screened in vitro cytotoxic assay against four cancer cell lines namely, HeLa, HEPG-2, HCT-116 and MCF-7 using doxorubicin (DOX) as a reference using MTT assay. The results demonstrated that compounds 4b and 4j exhibited the highest antitumor activity with IC50 =6.22-16.44  μM in comparable to DOX (IC50 = 4.17-5.57μM). The most active hybrids 4b and 4j were further subjected to multi-targeting assays against EGFR, VEGFR-2, and Topo II. They showed good to moderate inhibitory activities. In addition, flow cytometric analysis of 4b and 4j inhibited cell population of MCF-7 cells in the S phase. Compound 4b, and 4j were further evaluated using molecular docking and dynamics simulations (20 ns) and the EGFR, TOPII, or VEGFR-2 receptor protein. All the data sets accurately predict the strongest binding affinity for the selected compounds, as evidenced by the highest free binding energy from MM/GBSA calculations and significant amino acid steric interactions. Furthermore, the RMS/RMSF/Rg/SASA dynamics parameters show the formed complexes demonstrate satisfactory stability. The ADMET properties indicate that the selected new ligands have shown a promising drug-like profile and can be considered potential candidates for future anti-cancer therapies, with perspective validating their anticancer activity by in vitro studies.

The citrus flavonoid nobiletin prevents the development of doxorubicin-induced heart failure by inhibiting apoptosis

BACKGROUND

The anthracycline anticancer drug doxorubicin (DOX) induces myocardial cell death and heart failure. The aim of the present study was to investigate whether nobiletin (NOB), a natural flavonoid isolated from citrus peel, has a protective effect against DOX-induced cardiotoxicity.

METHODS AND RESULTS

H9C2 cells were pretreated with 100 μM NOB and then treated with 1 μM DOX. An MTT assay revealed that NOB improved the decreased cell viability induced by DOX. A TUNEL assay showed that NOB treatment improved DOX-induced apoptosis in H9C2 cells. Western blotting indicated that DOX-induced increases in cleaved caspase-3 and -9 expression were significantly suppressed by NOB treatment. Motion field imaging of human iPS cell-derived cardiomyocyte sheets showed that NOB significantly suppressed a DOX-induced reduction of their contractile function. Next, to investigate the effect of NOB in vivo, DOX was intraperitoneally administered to mice. Echocardiography showed that oral administration of NOB reduced DOX-induced left ventricular systolic dysfunction, and a TUNEL assay showed that oral administration also inhibited apoptosis in the mouse heart.

CONCLUSIONS

These results indicate that NOB treatment suppressed DOX-induced cardiotoxicity by reducing apoptosis. Further study of the mechanism of this effect may lead to the development of a novel therapy for DOX-induced heart failure.

Buthionine sulfoximine acts synergistically with doxorubicin as a sensitizer molecule on different tumor cell lines

The chemotherapeutic drug doxorubicin (DOX) has been widely used for treating solid tumors attributed to its antiproliferative effectiveness; however, its clinical use is limited due to side effects, including cardiotoxicity, myelosuppression, and drug resistance. Combining DOX with buthionine sulfoximine (BSO), a glutathione (GSH) synthesis inhibitor, showed promising results in overcoming these adverse effects, potentially reducing the required DOX dose while maintaining efficacy. The aim of the present study was to examine the effects of different concentrations of BSO and DOX, both individually and in combination, utilizing B16/F10 (murine melanoma), SNB-19 (human glioblastoma), S180 (murine sarcoma), and SVEC4-10 (murine endothelial) cell lines. Cell viability, migration, and clonogenicity were assessed using the following assays MTT, scratch, and colony formation. Antioxidant levels of GSH, as well as activities catalase (CAT), and superoxide dismutase (SOD) were measured. BSO alone exhibited minimal cytotoxic effects, while DOX alone reduced cell viability significantly. The combination of BSO+DOX decreased IC50 values for most cell lines, demonstrating a synergistic effect, especially in B16/F10, S180, and SVEC4-10 cells. BSO+DOX combination significantly inhibited cell migration and clonogenicity compared to DOX alone. While GSH levels were decreased with BSO+DOX treatment activities of CAT and SOD increased following DOX administration but remained unchanged by BSO. These results suggest that BSO may be considered a valuable tool to improve DOX therapeutic efficacy, particularly in cases of chemotherapy-resistant tumors, as BSO enhances DOX activity while potentially reducing systemic chemotherapeutic drug toxicity.

Dl-3-n-Butylphthalide enhances the survival of rat bone marrow stem cells via a reactive oxygen species mediated Erk1/2 signaling pathway

Survival of bone marrow stem cells (BMSCs) is crucial for successful bone marrow transplantation. However, the underlying molecular mechanisms remain inadequately understood. Our previous research has demonstrated that dl-3-n-butylphthalide (NBP) can protect rat BMSCs (rBMSCs) from cell death via its antioxidative properties and by activating the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway. The findings suggest that the PI3K/Akt pathway may be one of the primary targets through which NBP exert its protective effects. In this study, we explored an additional signaling pathway to further elucidate the molecular mechanisms involved in NBP-mediated protection against oxidative stress injury in rBMSCs. Oxidative stress was induced in rBMSCs using hydrogen peroxide (H2O2), imitating the cerebral ischemia microenvironment surrounding transplanted cells in vitro. The protective effects of NBP on rBMSCs against apoptosis were observed, achieving by decreasing the level of reduce reactive oxygen species (ROS) and malondialdehyde (MDA) while simultaneously increasing the concentration of superoxide dismutase (SOD). Notably, these protective effects were partially inhibited by U0126, an extracellular signal-regulated kinase1/2 (Erk1/2) inhibitor, which enhanced the suppression of NBP's antiapoptotic effects. Our results indicated that NBP could protect rBMSCs from apoptosis through modulation of ROS/Erk pathways. Further investigations are warranted to clarify the unknown mechanisms.

In vitro assessment of aryl hydrocarbon, estrogen, and androgen receptor-mediated activities of secondary organic aerosols formed from the oxidation of polycyclic aromatic hydrocarbons and furans

Biomass burning constitutes a significant source of fine particulate matter (PM2.5) in the atmosphere, particularly during winter due to residential wood heating. This source also emits substantial quantities of volatile and semi-volatile organic compounds, leading through (photo-)chemical and physical processes, to the formation of secondary organic aerosols (SOAs), accounting for a significant fraction of PM2.5. The current understanding of the biological effects of SOA resulting from the oxidation of major gaseous precursors emitted by biomass burning (e.g., polycyclic aromatic hydrocarbons (PAHs), phenols, furans) is still limited. Mechanism-based in vitro cellular bioassays targeting toxicologically relevant modes of action have proven valuable in assessing and quantifying the overall biological activity of complex mixtures like SOA, thereby revealing the presence of toxicologically relevant compounds. The main objective of this study was to investigate, using a battery of in vitro mechanism-based cellular bioassays, the aryl hydrocarbon (AhR), estrogen (ER), and androgen receptor (AR)-mediated activities of laboratory-generated SOA resulting from the oxidation of four PAHs and three furans. SOA was produced using an oxidation flow reactor (OFR) under either daytime (OH radicals) or nighttime (NO3 radicals) conditions. Furan-derived SOA did not exhibit any biological activity with the targeted endpoints. PAH-derived SOA, formed from AhR weakly or inactive PAHs, showed significant AhR-mediated activities. Notably, SOA resulting from naphthalene and acenaphthylene + acenaphthene demonstrated the highest AhR activation potency, with greater activities observed for SOA formed through NO3 radical oxidation. No endocrine-disrupting activity was observed for the PAH-derived SOA, similar to the individual parent PAHs (with the exception of fluorene and phenanthrene PAHs which were weekly anti-androgenic). These findings underscore the substantial contribution of PAH-derived SOA to the AhR-mediated activities of PM.

ZIF-8/doxorubicin nanoparticles camouflaged with Cucurbita-derived exosomes for targeted prostate cancer therapy

Development of biomimetic drug delivery systems (DDSs) holds great promise to overcome various nanoparticle-associated hindrances in cancer therapy. However, producing biomimetic nanoparticles camouflaged by animal cell-secreted exosomes presents several challenges, including low yield and some ethical considerations. Herein, we designed a biomimetic nanocarrier composed of zeolitic imidazolate framework-8 (ZIF-8) encapsulating doxorubicin (DOX) as the core and a shell of exosome-like nanoparticles (EXO) derived from Cucurbita moschata (CEXO). This design enhances safety and addresses some exosome limitations. The CEXO@ZIF-8/DOX platform was further functionalized with an epithelial cell adhesion molecule (EpCAM) aptamer (Apt-CEXO@ZIF-8/DOX) for targeted delivery to prostate cancer (PC) cells. After investigating the anticancer activity of CEXOs on PC-3 cells, the exosomes were utilized to coat ZIF-8/DOX. The immune evasion capability, cellular uptake, and anticancer effects of nanoplatforms were assessed. Moreover, the in vivo effectiveness of the targeted platform in inhibiting tumor growth and minimizing the adverse effects, was assessed using immunocompromised C57BL/6 mice bearing human PC-3 tumors. Cucurbita exosomes decreased cell viability and induced cell cycle arrest and apoptosis in PC-3 cells without affecting the normal cells. The biomimetic CEXO@ZIF-8/DOX improved immune escaping ability and hemocompatibility. The targeted nanocarrier, with augmented uptake and cellular toxicity in EpCAM-positive PC-3 cells, indicated active targeting efficacy mediated by the EpCAM aptamer. These results were supported by animal experiments that implied the effectiveness of Apt-CEXO@ZIF-8/DOX in inhibiting tumor growth without adverse side effects. This study introduces a novel functional nanocarrier that could potentially revolutionize DDSs by utilizing safer and more biocompatible plant exosomes.

Venlafaxine-PLGA nanoparticles provide a fast onset of action in an animal model of depression via nose-to-brain

BACKGROUND

Current treatment of depression is hindered by the delayed onset of the action of antidepressant drugs, often resulting in treatment failure. Therefore, new therapeutic solutions are imperative.

METHODOLOGY

Venlafaxine-loaded poly(lactic-co-glycolic acid) nanoparticles were produced by a double emulsion-solvent evaporation method. Cellular safety assessment and internalization assays were carried out in vitro in human olfactory neuroepithelium cells. The antidepressant effect of intranasal (nose-to-brain) nanoparticle administration was assessed in animals submitted to an animal model of depression by behavioral tests, including open-field, sucrose preference test and tail suspension test.

RESULTS

The drug entrapment efficiency (55-65 %), particle size (190-210 nm), polydispersity index (<0.2), and zeta potential (-20 mV) of Venlafaxine-loaded poly(lactic-co-glycolic acid) nanoparticles were determined to be adequate. Nanoparticles did not show cytotoxic effects. Cell viability was more than 90 % for all formulations and concentrations assayed. The results of the quantitative and qualitative cell uptake assays were consistent, showing an evident internalization of the nanoparticles into the cells. Furthermore, venlafaxine-loaded nanoparticles administered for just 7 days were able to reverse the phenotype induced by a depressive-like model, showing a significant antidepressant-like effect compared to those treated with free venlafaxine.

CONCLUSIONS

These findings indicated that intranasal venlafaxine-loaded poly(lactic-coglycolic acid) nanoparticles could become a viable technique for improving venlafaxine brain uptake via nose-to-brain. It could also be a promising nanoplatform for enhancing the treatment of depression.

Genotoxicity, mutagenicity, and immunotoxicity assessment of green silver nanoparticles from Croton urucurana on neotropical snails Biomphalaria glabrata

Green silver nanoparticles (G-Ag NPs) have been indicated as safer nanotechnology in nanomedicine, especially for controlling microorganisms, vectors, and gastropods of medical importance. However, their mechanisms of action and ecotoxicity in aquatic organisms remain unknown. Thus, the current study aimed to investigate the effects of G-Ag NPs synthesized through Croton urucurana leave aqueous extract on the neotropical freshwater snail Biomphalaria glabrata after in vivo exposure using multi-biomarker responses in hemocytes. Adult snails were exposed to G-Ag NPs (0.05 and 0.14 mg L-1) or leave aqueous extract (5.4 mg L-1) for 7 days. Genotoxicity (comet assay), mutagenicity (micronucleus test and nuclear abnormality assay), and immunotoxicity (phagocytosis assay by flow cytometry) were analyzed in hemocytes. Results showed that G-Ag NPs induced high mortality and genotoxic effects (DNA damage) compared to leave aqueous extract and negative control groups. G-Ag NPs also induced mutagenic effects (nuclear alterations), mainly notched and blebbed nuclei. Also, G-Ag NPs and extract did not change the phagocytic activity and cell viability of hemocytes. These findings contribute to understanding the toxicity of green nanoparticles in freshwater gastropods and represent a pioneering effort to evaluate the effects of G-Ag NPs and the C. urucurana aqueous extract in B. glabrata hemocytes. Overall, the immune system of gastropods is a target of green nanoparticle toxicity.

Evaluation of the antimicrobial activity of chitosan- and curcumin-capped copper oxide nanostructures against multi-drug-resistant microorganisms

The emergence of multi-drug-resistant microorganisms presents a serious threat to infection control, for which new antimicrobial strategies are urgently needed. Herein, the antimicrobial activities of copper oxide nanoparticles capped with curcumin (Cur-CuO NPs) and copper oxide nanoparticles capped with chitosan (CS-CuO NPs) were investigated. They were prepared via the co-precipitation method. A total of 180 clinical ICU patients were found to have 70% Gram-negative and 30% Gram-positive isolates. Antimicrobial susceptibility testing indicated resistance of these isolates to 14 among the 21 tested antibiotics. Physicochemical properties of the curcumin-capped (Cur-CuO NPs) and chitosan-capped (CS-CuO NPs) copper oxide nanoparticles were identified using UV-vis spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta-potential (ζ), and Fourier transform infrared (FT-IR) spectroscopy. Cur-CuO- and CS-CuO-NPs exhibited potent antimicrobial efficacy, wherein CS-CuO NPs were found to possess a lower minimum inhibitory concentration (MIC) (3.9-15.6 μg mL-1) than Cur-CuO NPs (14.5-31.2 μg mL-1). Biocompatibility assay showed that Cur-CuO NPs were safer with an IC50 dose of 74.17 μg mL-1 than CS-CuO NPs with an IC50 dose of 41.01 μg mL-1. Results revealed that the Cur-CuO- and CS-CuO-NPs have the potential to be safely used as effective antimicrobial agents in clinical applications at low concentrations (6.25-12.5 μg mL-1).

Glycerol-Based Polymer to Improve the Cellular Uptake of Liposomes

Nanomedicines modify the pharmacology of pharmaceutical ingredients, but most require cell internalization to deliver their payloads. Hence, modifying the surface properties of nanomedicines can improve their interactions with cells and modulate their pharmacology. Herein, we devised a polymer that increases how nanomedicines are internalized by cells. The alkylated poly(monoglycerol acrylate) (PMGA) polymer was synthesized by reversible addition-fragmentation chain-transfer (RAFT) polymerization with a terminal double 18-carbon moiety that allows its anchoring on the surface of liposomes. PMGA-decorated liposomes are internalized more efficiently in immune cells, compared to formulations without the polymer. Using inhibitors of internalization pathways, we established that PMGA promotes cell entry by the fast endophilin-mediated endocytosis (FEME). In comparison, noncoated control liposomes were mostly internalized by clathrin-mediated endocytosis. This work highlights the potential of PMGA to increase the internalization of nanomedicines by immune cells, and target a novel internalization pathway.

Comparative analysis of N/TERT-1 and N/TERT-2G keratinocyte responses to oxidative stress and immune challenges

The responses of N/TERT-1 and N/TERT-2G keratinocyte cell lines to oxidative stress and immune challenges were investigated to assess their suitability for dermatological testing. The cell lines were exposed to various stimuli, including PAMPs, DAMPs, H₂O₂, and menadione, to assess cytokine production, oxidative stress markers, cell viability, apoptosis, and membrane integrity. IL-1α, IL-6, IL-8, TNF-α, and TGF-β levels significantly increased in N/TERT-1 cells following exposure to LPS, while N/TERT-2G cells remained unaffected. Both cell lines showed increased production of IL-1α, IL-1β, TNF-α, IL-6, and IL-8 in response to dsDNA and LMW and HMW Poly I:C, although TGF-β significantly decreased only in N/TERT-1 cells. In response to H₂O₂, a dose-dependent increase in cytokine levels was observed in N/TERT-2G, whereas N/TERT-1 did not exhibit a clear dose-dependent response. Markers of oxidative stress, including SOD and GSH, displayed similar patterns in both cell lines, with N/TERT-2G showing slightly higher sensitivity. Lipid peroxidation and mitochondrial membrane potential fluctuations were more pronounced in N/TERT-2G, suggesting greater oxidative stress sensitivity. The baseline GSH levels were higher in N/TERT-1 cells, which may contribute towards the enhanced resilience to oxidative stress. Despite decreased viability in MTT assays following H₂O₂ exposure, the lack of significant changes in cleaved Caspase-3 levels indicated that apoptosis was not the primary mechanism of cell death. These findings highlight the distinct characteristics of N/TERT-1 and N/TERT-2G cells, with N/TERT-1 showing higher baseline resilience to oxidative stress and N/TERT-2G displaying greater sensitivity, particularly to H₂O₂. The study underscores the importance of selecting the appropriate cell line for specific research applications in skin biology and disease modelling, considering the differences in their responses to oxidative and immune challenges.

Pharmacokinetic Prediction and Cytotoxicity of New Quercetin Derivatives

Quercetin (QUE) possesses various pharmacological properties; however, its low bioavailability and solubility hinder its beneficial effects. Enzymatic glycosylation has been explored to improve these aspects. In the present study, we used a sucrose phosphorylase variant to catalyze the regioselective transglucosylation of QUE, predicted the pharmacokinetic properties and toxicity of these molecules using in silico tools, and evaluated their cytotoxicity compared to the original molecule and a β-glucosylated derivative of QUE. Three α-glucosylated derivatives were obtained, which demonstrated improved pharmacokinetics, including a higher volume of distribution and lower clearance rate, with minimal likelihood of cytochrome P450 enzyme inhibition compared to QUE. QUE and the β-glucosylated derivative exhibited cytotoxicity in both cell types evaluated, whereas their α-glucosylated derivatives were nontoxic. The results presented provide an insight into the predicted behavior of these molecules in the body and, combined with cytotoxicity evaluation, will serve as a foundation for investigating the biological effects and mechanisms of action of these new molecules.

Florasulam Is a Potent Inhibitor of Mycobacterium tuberculosis Acetohydroxyacid Synthase and Possesses In Vivo Antituberculosis Activity

Tuberculosis (TB) remains as a leading cause of morbidity and mortality, accounting for ∼1.3 million fatalities worldwide per year. There are two major concerns: (i) the rise in the number of multi- and extensively drug-resistant strains of TB and (ii) the significant side-effects related to the use of many of the current therapies to treat drug-resistant and drug-sensitive TB alike. Thus, there is an ongoing need to discover new drugs and drug targets to combat this disease. Here, acetohydroxyacid synthase (AHAS), the first enzyme in the branched-chain amino acids (BCAAs) biosynthesis pathway, is comprehensively investigated as such a drug target. All five chemical classes of plant AHAS inhibitors, established as commercial herbicides, were assessed as leads. Members of the triazolopyrimidine family (e.g., metosulam, penoxsulam, and florasulam) are the most potent inhibitors of Mycobacterium tuberculosis AHAS (MtbAHAS) with Ki values as low as 20 nM. These compounds also exhibit the property of accumulative time-dependent inhibition, a feature that appears to be crucial for herbicidal activity and more generally for biocidal activity. Of these, the anti-TB activity of florasulam was the most effective, with an MIC of 500 nM against virulent Mtb grown in culture. This compound is also effective in killing intramacrophage Mtb and reduces bacterial load, as compared to vehicle-only by 13-fold in the lungs of mice infected with Mtb. Thus, triazolopyrimidines as AHAS inhibitors, and in-particular florasulam, represents a promising new class of leads for anti-TB drug development.

Design and Synthesis of New pyrazole Hybrids Linked to Oxime and Nitrate Moieties as COX-2, EGFRL858R/T790M Inhibitors and Nitric Oxide Donors with dual Anti-inflammatory/Anti-proliferative Activities

Two new series of pyrazole derivatives 14a-l and 17a-c with oxime/nitrate moieties as EGFRWT, mutant (EGFRL858R/T790M) and COX-2 inhibitors were synthesized and evaluated for anti-proliferative and anti-inflammatory activities. Compounds 14c, 14e, 14 g, 14i-l, 17b and 17c exhibited COX-2 selectivity in the range of (S.I. = 17-42) when compared to celecoxib (S.I. = 20.43). Concerning anti-neoplastic activity, screening was carried out against 60 human cancer cell lines by (NCI); Nine compounds (14c, 14e, 14 g, 14i-l, 17b and 17c) showed excellent inhibitory activity against all cancer cell lines especially non-small cell lung cancer (NSCLC). Further cytotoxicity testing of compounds 14c, 14e, 14 g, 14i-l, 17b and 17c was conducted on established EGFRT790M/L858R-resistant NSCLC (H1975), all tested compounds except 14 l exhibited potent activity (IC50 = 3.02-27.32 μM) which is higher than that of osimertinib (IC50 = 37.29 μM). It was noted that compound 17c, showed cell cycle arrest at G0/G1 phase of NSCLC (H1975) cells. In addition, compounds 14c, 14e, 14 g, 14i-l, 17b and 17c induced improved selective inhibitory activity against double mutant EGFRL858R/T790M tyrosine kinases with IC50 in the range of (0.031-0.076 μM, with selectivity index range S.I. of 2.5-14.58) which was comparable to that of osimertinib (IC50 = 0.037 μM, with S.I. of 1.89). The most potent anti-cancer compounds 14c, 14e, 14 g, 14i-l, 17b and 17c released NO in a slow rate of (1.45-3.37 %). Finally, applying covalent docking, we identified the covalent binding of 14 g, 14 k, and 17c with Cys797, providing insights into their potential as irreversible inhibitors targeting EGFRL858R/T790M protein.

Coumarin MAMMEA A/BB cytotoxicity inhibits the chemoresistance and migration of glioblastoma cells in vitro

High-grade gliomas are the most aggressive brain tumors, which have no effective treatment. This work investigated a new anti-glioma strategy using mammea A/BB in vitro, a 4-phenylcoumarin isolated from the roots of Kielmeyera argentea. This work evaluated the cytotoxicity of mammea A/BB to human glioblastoma (U251), rat glioma (C6) cells and rat astrocytes in primary culture, comparing to temozolomide (TMZ) by MTT test. Cell migration assay, morphological analysis of DAPI-labeled nuclei and immunofluorescence for P-glycoprotein (P-gp) were also performed. After 72 h, the mammea A/BB significantly induced cytotoxicity in a concentration-dependent manner in U251 and C6 cells, with the EC50 27 ± 2 μM and 57 ± 14 μM, respectively. The natural compound was not cytotoxic to astrocytes in primary culture up to 200 μM. It was possible to observe a significant inhibition of tumoral cell migration in treatments with 10 mM mammea A/BB. Both cell lines were resistant to TMZ, but significantly sensitive to mammea A/BB. The percentage of picnotic nuclei of cells treated with 30 mM mammea A/BB was higher than the control. Besides, the treatment with mammea A/BB showed no significant difference in P-gp expression, but it was increased in TMZ treatment after 72 h. Even with cell lines presenting different molecular profiles, the results indicate that mammea A/BB is a promising candidate as a new antitumor drug against glioma cells in vitro.

Synthesis, Molecular Docking, and Biological Activity of New EGFR-Targeted Photosensitizers Based on Cationic Porphyrins Encapsulated into Pluronic F127 Micelles

The development of new effective photosensitizers (PS) for photodynamic therapy (PDT) is one of the important tasks in medical and organic chemistry. PSs inhibiting epidermal growth factor receptors (EGFR) overexpressed in cancer cells are of particular importance. In this work, we proposed the design and molecular docking of novel hybrid photosensitizers based on meso-aryl-substituted porphyrins and the Erlotinib molecule, a clinically approved tyrosine kinase inhibitor. The spacer length between the macrocycles and Erlotinib, hydrophilicity, and hydrophobicity of the porphyrin ring substituents were varied in the obtained compounds to evaluate structure-activity relationships (SAR). Photophysical and photochemical characteristics were studied for all of the received compounds in the presence of solubilizers suitable for the creation of dosage forms. Nanomicelles based on Pluronic F127 were obtained and characterized for the received compounds. In vitro biological tests on three cancer cell lines, MCF-7 (breast carcinoma), A431 (epidermoid carcinoma), MDA-MB-231 (breast adenocarcinoma), and normal NKE cells (human kidney epithelial cells) were performed, which showed low dark toxicity as well as light-induced activity of conjugates in the nanomolar range. Confocal microscopy experiments showed preferred accumulation of UB-2 and a lower accumulation of UB-3 PSs. In the case of UB-3, we observed a pronounced colocalization with early endosome antigen (EEA1). Also, cell apoptosis and inhibition of phosphorylation of EGFR were demonstrated for the UB-3 compound. Thus, the proposed design of targeting PS containing cationic pyridyl moieties and a linker between the porphyrin macrocycle and Erlotinib can contribute to antitumor PDT.

A simple approach to orthogonally protected 2,3-diaminopropanols: intermediates for l- and d-Dap-containing peptidomimetics

A simple approach to orthogonally protected 2,3-diaminopropanols from easily available d- and l-erythrofuranose has been accomplished. The pivotal step involved a cascade Overman rearrangement to install two novel C-N bonds and create the desired diamino alcohol motif, while a one-pot ozonolysis/reductive workup accompanied by the rational execution of suitable functional group transformations allowed the carbon skeleton of the target compounds to be completed. A series of the synthesised diaminopropanols was evaluated regarding their capacity to alter proliferation of selected cancer cell lines.

Synthesis of Marine-Inspired Multifaceted DNA Damaging Spirooxindoles Combating NSCLC and Associated Bacterial Infection

Targeted therapeutics have gained prominence in combating non-small cell lung carcinoma (NSCLC) and opportunistic bacterial infections like Staphylococcus aureus (S. aureus). This study explores dual-acting marine-inspired spirooxindoles to limit NSCLC and opportunistic bacteria. Pharmacophoric motifs from antitumor and antibacterial marine products were merged into a new series of pyrazole-clubbed spirooxindoles via a stereoselective [3 + 2] cycloaddition reaction. MTT screening identified 4e, 4i, and 4p-4s as potent cytotoxic agents, with 4p showing exceptional activity (IC50 = 0.042 μM) and tumor selectivity (SI = 58.28). 4p exhibited antibacterial efficacy against S. aureus (MIC = 25 μg/mL). DNA damage studies using a terbium(III) chloride biosensor revealed 4p's ability to damage both calf thymus and S. aureus DNA at low concentrations. Docking simulations presumed that 4p binds between DNA strands, while apoptosis studies indicated it induced G1/S phase cell cycle arrest and increased A549 apoptosis by 33.65%. These findings highlight 4p as a promising lead for further studies.

Embryonic Zebrafish Irritant-evoked Hyperlocomotion (EZIH) as a high-throughput behavioral model for nociception

Behavioral models have served a key role in understanding nociception, the sensory system by which animals detect noxious stimuli in their environment. Developing zebrafish (Danio rerio) are a powerful study organism for examining nociceptive pathways, given the vast array of genetic, developmental, and neuroscience tools available for these animals. However, at present there are few widely-adopted behavioral models for nociception in developing zebrafish. This study examines the locomotor response of hatching-stage zebrafish embryos to dilute solutions of the noxious chemical and TRPA1 agonist allyl isothiocyanate (AITC). At this developmental stage, AITC exposure induces a robust uniphasic hyperlocomotion response. This behavior was thoroughly characterized by determining the effects of pre-treatment with an array of pharmacological agents, including anesthetics, TRPA1 agonists/antagonists, opioids, NSAIDs, benzodiazepines, SSRIs, and SNRIs. Anesthetics suppressed the response to AITC, pre-treatment with TRPA1 agonists induced hyperlocomotion and blunted the response to subsequent AITC exposures, and TRPA1 antagonists and the opioid buprenorphine tended to reduce the response to AITC. The behavioral responses of zebrafish embryos to a noxious chemical were minimally affected by the other pharmacological agents examined. The feasibility of using this behavioral model as a screening platform for drug discovery efforts was then evaluated by assaying a library of natural product mixtures from microbial extracts and fractions. Overall, our results indicate that irritant-evoked locomotion in embryonic zebrafish is a robust behavioral model for nociception with substantial potential for examining the molecular and cellular pathways associated with nociception and for drug discovery efforts.

New bis-norditerpene by biotransformation of favelines from Cnidoscolus quercifolius using Umbelopsis isabellina as biocatalyst

Favelines, tricyclic benzylcycloheptene diterpenes predominantly found in Cnidoscolus quercifolius, have demonstrated significant cytotoxic activity against human cancer cell lines, including melanoma. In this study, we employed a combinatorial approach to screen microbial strains for biotransformation, focusing on regioselective oxidation of the cyclohexyl ring in the faveline core structure. This strategy, applied directly to the crude plant extract, enabled the rapid identification of Umbelopsis isabellina as the active strain. Subsequent preparative biotransformation yielded a novel bis-norditerpene, 14-hydroxy-isofavelol (3). The new compound exhibited moderate cytotoxic activity (IC₅₀ = 68.8 μM) against chemoresistant human melanoma A2058 cells, which are resistant to dacarbazine but sensitive to vemurafenib. Compound 3 enhanced the cytotoxic effect of vemurafenib, reducing its IC₅₀ from 24.8 to 9.63 μM. This work demonstrates the utility of microbial biotransformation for generating new bioactive natural product derivatives and highlights the potential of 14-hydroxy-isofavelol as a chemosensitizing agent in melanoma therapy.

Virucidal Efficacy of Laser-Generated Copper Nanoparticle Coatings against Model Coronavirus and Herpesvirus

High-efficiency antiviral surfaces can be an effective means of fighting viral diseases, such as the recent COVID-19 pandemic. Copper and copper oxides, their nanoparticles (NPs) (CuNPs), and coatings are among the effective antiviral materials having internal and external biocidal effects on viruses. In this work, CuNP colloids were produced via femtosecond laser ablation of the metal target in water, a photophysical, cost-effective green synthesis alternative utilizing sodium citrate surfactant stabilizing the NPs. Raman spectroscopy and X-ray diffraction studies confirmed that the 32 nm mean size CuNPs are mixtures of mainly metallic copper and copper(I) oxide. Polyvinyl butyral was utilized as the binding agent for the CuNPs deposited via high-throughput spray-coating technology. The virucidal efficacy of such coatings containing Cu content ranging from 2.9 to 11.2 atom % was confirmed against animal-origin coronavirus containing ribonucleic acid, the agent of avian infectious bronchitis (IBV), and herpesvirus containing DNA, the agent of bovine herpesvirus (BoHV-1) infection. It was demonstrated that after a short time of exposure, the Cu NP-based coatings do not have a toxic effect on the cell cultures while demonstrating a negative effect on the biological activity of both model viruses that was confirmed by quantification of the viruses via the determination of tissue culture infectious dose (TCID50) virus titer and their viral nucleic acids via determination of threshold cycle (Ct) employing real-time polymerase chain reaction analysis. The assays showed that the decrease in TCID50 virus titer and increase in Ct values correlated with Cu content in Cu NP-based coatings for both investigated viruses. Contact with coatings decreased IBV and BoHV-1 numbers from 99.42% to 100.00% and from 98.65% to 99.96%, respectively. These findings suggest that CuNPs show inhibitory effects leading to the inactivation of viruses and their nuclei regardless of the presence of a viral envelope.

Multimeric interacting interface of biologically synthesized zinc oxide nanoparticle corona efficiently sequesters α-synuclein against protein fibrillation

Parkinson's disease (PD) is characterized by the loss of dopaminergic neurons along with the accumulation of amyloid plaques with alpha-synuclein (αS) as the major constituent. αS is an intrinsically disordered protein with the potential to undergo a cascade of structural transitions from a soluble disordered conformation to ordered cross-β-sheet-rich insoluble amyloid fibrils. Small molecules like polyphenols and peptides with anti-amyloidogenic potential can mitigate fibrillation in vitro but fail in vivo owing to poor bioavailability. To overcome this problem, a platform that simultaneously enhances the bioavailability of the mitigators and efficiently sequesters αS monomers against amyloidosis is needed. Accordingly, herein, the sequestering potential of surface-moderated zinc oxide nanoparticles was explored; in silico and in vitro studies showed that the moderated nano-interfaces efficiently sequestered αS in amorphous aggregates, which were termed as flocs. Moreover, GC-MS-based analysis of the bio-nano corona highlighted the rationale for efficient sequestering of αS monomers against amyloidosis by the biologically synthesized zinc oxide nanoparticle compared with other nanoparticle surfaces. Thus, this work exemplifies the multimeric interacting interface as a platform to efficiently sequester the αS protein and simultaneously enhance the bioavailability of the phytochemicals.

A formulation containing Cymbopogon flexuosus essential oil: improvement of biochemical parameters and oxidative stress in diabetic rats

Diabetes mellitus (DM) is a highly prevalent public health problem characterized by hyperglycemia that causes complications due to the generation of reactive oxygen species and oxidative damage. Studies have shown that essential oils containing citral, such as lemongrass, have various biological activities, including bactericidal, antiviral, antifungal, antioxidant, and hypoglycemic effects. Therefore, this study aims to obtain a microemulsified formulation containing the essential oil of Cymbopogon flexuosus (EOCF) and to evaluate its antioxidant and antidiabetic activity in diabetic rats. The microemulsion (ME) was obtained after consulting the corresponding pseudoternary phase diagram and showed stability, isotropy, Newtonian behavior, nanometric size (15.2 nm), and pH 4.2. Both EOCF and the ME showed high antioxidant activity, but the ME resulted in greater antioxidant activity, potentiating the activity of isolated EOCF. Finally, male Wistar rats (3 months old, 200-250 g) with streptozotocin-induced type-1 DM were supplemented with EOCF and ME (32 mg/kg) for 21 days. Both EOCF and ME supplementation resulted in reduced blood glucose levels and improved lipid profiles when compared to the control group. Additionally, the ME was able to provide additional benefits, such as reduced liver damage, improved renal function, reduced systemic inflammation, and increased high-density lipoprotein levels. Overall, the results show that EOCF was efficiently incorporated into the microemulsion, improving its antioxidant activity and showing promising results for use in the treatment of DM via the oral route.