Publications

Abstract The pharmacological interest in mitochondria is very relevant since these crucial organelles are involved in the pathogenesis of multiple diseases, such as cancer. In order to modulate cellular redox/oxidative balance and enhance mitochondrial function, numerous polyphenolic derivatives targeting mitochondria have been developed. Still, due to the drug resistance emergence in several cancer therapies, significant efforts are being made to develop drugs that combine the induction of mitochondrial metabolic reprogramming with the ability to generate reactive oxygen species, taking into consideration the varying metabolic profiles of different cell types. We previously developed a mitochondria-targeted antioxidant (AntiOxCIN6) by linking caffeic acid to lipophilic triphenylphosphonium cation through a 10-carbon aliphatic chain. The antioxidant activity of AntiOxCIN6 has been documented but how the mitochondriotropic compound impact energy metabolism of both normal and cancer cells remains unknown. We demonstrated that AntiOxCIN6 increased antioxidant defense system in HepG2 cells, although ROS clearance was ineffective. Consequently, AntiOxCIN6 significantly decreased mitochondrial function and morphology, culminating in a decreased capacity in complex I-driven ATP production without affecting cell viability. These alterations were accompanied by an increase in glycolytic fluxes. Additionally, we demonstrate that AntiOxCIN6 sensitized A549 adenocarcinoma cells for CIS-induced apoptotic cell death, while AntiOxCIN6 appears to cause metabolic changes or a redox pre-conditioning on lung MRC-5 fibroblasts, conferring protection against cisplatin. We propose that length and hydrophobicity of the C10-TPP+ alkyl linker play a significant role in inducing mitochondrial and cellular toxicity, while the presence of the antioxidant caffeic acid appears to be responsible for activating cytoprotective pathways.

Abstract A new library of non-nitrocatechol compounds (HetCAMs) was developed and their efficacy was compared to tolcapone, a standard COMT inhibitor for PD. Compound 9 emerged as the most potent inhibitor, showing selective inhibition of brain (IC50 = 24 nM) and liver (IC50 = 81 nM) MB-COMT over liver S-COMT (IC50 = 620 nM) isoforms. Although compound 9 presented higher IC50 values than tolcapone, it was more selective for brain MB-COMT than liver S-COMT. Unlike tolcapone, compound 9 is not a tight-binding inhibitor and is less cytotoxic to HepG2 and SK-N-SH cells. Additionally, compound 9 is predicted to cross the blood-brain barrier (BBB) by passive diffusion and chelate divalent metals like Fe(II) and Cu(II). The results demonstrate the potential of this rational drug design strategy for developing new CNS-active drug candidates, offering symptom relief via COMT inhibition that can provide a long-term, disease-modifying outcome (chelation of divalent metals) in PD.

Abstract The increasing interest in utilizing psychedelics for therapeutic purposes demands the development of tools capable of efficiently monitoring and accurately identifying these substances, thereby supporting medical interventions. 4-Bromo-2,5-dimethoxyphenethylamine (2C-B) has gained significant popularity as one of the most widely used psychedelic compounds in non-medical settings. In this study, we aimed to create a material with selective recognition of 2C-B by synthesizing a series of molecularly imprinted polymers (MIP) using 2C-B as the template and varying ratios of methacrylic acid (MAA) as the functional monomer (1:2, 1:3, and 1:4). Both thermal and microwave-assisted polymerization processes were employed. The molar ratio between the template molecule (2C-B) and functional monomer (MAA) was 1:4, utilizing a microwave-assisted polymerization process. Isotherm studies revealed a Langmuir's maximum absorption capacity (Bmax) value of 115.6 mu mol center dot mg-1 and Kd values of 26.7 mu M for this material. An imprint factor of 4.2 was determined for this material, against the corresponding non-imprinted polymer. The good selectivity against 14 other new psychoactive substances highlighted the material's potential for applications requiring selective recognition. These findings can contribute to the development of tailored materials for the detection and analysis of 2C-B, supporting advancements in non-medical use monitoring and potential therapeutic models involving psychedelics.

Abstract Substituted phenethylamines including 2C (2,5-dimethoxyphenethylamines) and NBOMe (N-(2-methoxybenzyl)phenethylamines) drugs are potent psychoactive substances with little to no knowledge available on their toxicity. In the present in vitro study, we explored the mechanisms underlying the neurotoxicity of six substituted phenethylamines: 2C-T-2, 2C-T-4, 2C-T-7 and their corresponding NBOMes. These drugs were synthesized and chemically characterized, and their cytotoxicity (0-1000 mu M) was evaluated in differentiated SH-SY5Y cells and primary rat cortical cultures, by the NR uptake and MTT reduction assays. In differentiated SH-SY5Y cells, mitochondrial membrane potential, intracellular ATP and calcium levels, reactive oxygen species production, and intracellular total glutathione levels were also evaluated. All the tested drugs exhibited concentration-dependent cytotoxic effects towards differentiated SH-SY5Y cells and primary rat cortical cultures. The NBOMe drugs presented higher cytotoxicity than their counterparts, which correlates with the drug's lipophilicity. These cytotoxic effects were associated with mitochondrial dysfunction, evident through mitochondrial membrane depolarization and lowered intracellular ATP levels. Intracellular calcium imbalance was observed for 2C-T-7 and 25T7-NBOMe, implying a disrupted calcium regulation. Although reactive species levels remained unchanged, a reduction in intracellular total GSH content was observed. Overall, these findings contribute to a deeper understanding of these drugs, shedding light on the mechanisms underpinning their neurotoxicity.

Abstract Antimicrobial resistance (AMR) poses a global threat to human health, as exemplified by the devastating impact of ESKAPE pathogens, reducing treatment options, increasing disease burden, and elevating death rates due to treatment failure. This looming health threat has rekindled interest in the development of new antimicrobial therapies. In this study, a library of 49 structurally related quaternary heteronium salts (QHSs), such as quaternary ammonium and phosphonium compounds, was screened at a concentration of 32 mu g/mL against five ESKAPE pathogens (methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli), as well as the yeast -like fungus Candida albicans. The preliminary high -throughput screening (HTS) data revealed that QHSs with longer alkyl chain lengths (>= 12 carbons) exhibited broad-spectrum antimicrobial activity, with the C14-C16 homologous demonstrating the highest potency. The alkyl-triphenylphosphonium salts 1a-g exhibited the most significant antimicrobial activity among all tested compound series. The compounds identified as active in the initial HTS underwent confirmation assays to determine minimum inhibitory concentration (MIC) and cytotoxicity, following established protocols. Confirmatory assays identified 33 hits (MIC <= 16 mu g/mL), with 78% effective at very low concentrations (<= 0.25 mu g/mL). Seven hits showed safety profiles against HEK-293 cells and red blood cells at concentrations below 32 mu g/mL. Based on a comparative analysis of their potency against pathogenic microorganisms and cell toxicity, the salts of triphenylphosphonium and quinolinium with linear C8 hydrocarbon substituents (compounds 1b and 5b, respectively), and isoquinolinium, methylpyridinium and triethylammonium with linear C18 hydrocarbon substituents (compounds 3g, 4g, and 7g, respectively) have emerged as the most promising candidates for microbial growth control.

Abstract Non-alcoholic fatty liver disease (NAFLD) presents a pervasive global pandemic, affecting approximately 25 % of the world's population. This grave health issue not only demands urgent attention but also stands as a significant economic concern on a global scale. The genesis of NAFLD can be primarily attributed to unhealthy dietary habits and a sedentary lifestyle, albeit certain genetic factors have also been recorded to contribute to its occurrence. NAFLD is characterized by fat accumulation in more than 5 % of hepatocytes according to histological analysis, or >5.6 % of lipid volume fraction in total liver weight in patients. The pathophysiology of NAFLD/non-alcoholic steatohepatitis (NASH) is multifactorial and the mechanisms underlying the progression to advanced forms remain unclear, thereby representing a challenge to disease therapy. Despite the substantial efforts from the scientific community and the large number of pre-clinical and clinical trials performed so far, only one drug was approved by the Food and Drug Administration (FDA) to treat NAFLD/NASH specifically. This review provides an overview of available information concerning emerging molecular targets and drug candidates tested in clinical studies for the treatment of NAFLD/NASH. Improving our understanding of NAFLD pathophysiology and pharmacotherapy is crucial not only to explore new molecular targets, but also to potentiate drug discovery programs to develop new therapeutic strategies. This knowledge endeavours scientific efforts to reduce the time for achieving a specific and effective drug for NAFLD or NASH management and improve patients' quality of life.

Abstract Cancer is a major cause of death worldwide and novel anticancer agents for its better management are much needed. Benzopyrone-based compounds, such as chromones, possess several distinctive chemical and biological properties, of which the cytotoxicity against cancer cells seems to be prominent. In this study, two series of compounds based on chromen-4-one (3-10) and chromane-2,4-dione (11-18) scaffolds were synthesized in moderate/high yields and evaluated for cytotoxicity against HL-60, MOLT-4, and MCF-7 cancer cells using MTT assay. In general, the compounds exhibited moderate cytotoxic effects against the cancer cell lines, among which, a superior potency could be observed against MOLT-4 cells. Chroman-2,4dione (11-18) derivatives had overall higher potencies compared to their chromen-4-one (3-10) counterparts. Compound 13 displayed the lowest IC50 values against HL-60 (IC50, 42.0 +/- 2.7 mu M) and MOLT-4 cell lines (IC50, 24.4 +/- 2.6 mu M), while derivative 11 showed the highest activity against MCF-7 cells (IC50, 68.4 +/- 3.9 04). In conclusion, this study provides important information on the cytotoxic effects of chromone derivatives. Benzochroman-2,4-dione has been identified as a promising scaffold, which its potency can be modulated by tailored synthesis with the aim of finding novel and dissimilar anticancer compounds.