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1.
Int J Mol Sci ; 25(12)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38928111

RESUMO

Age-related macular degeneration (AMD) is strictly linked to chronic oxidative stress, inflammation, loss of epithelial barrier integrity, and often with abnormal new blood vessel development. In this study, the retinal epithelial cell line ARPE-19 was treated with pro-inflammatory transforming growth factor-beta (TGF-ß) to investigate the activity of vitamin D (VD) and sulforaphane (SF) in abating the consequences of oxidative stress and inflammation. The administration of VD and SF lowered reactive oxygen species (ROS) levels, and abated the related expression of the pro-inflammatory cytokines interleukin-6 and interleukin-8 induced by TGF-ß. We evaluated mitochondrial respiration as a source of ROS production, and we discovered that the increased transcription of respiratory elements triggered by TGF-ß was prevented by VD and SF. In this model of inflamed epithelium, the treatment with VD and SF also reduced the secretion of VEGF, a key angiogenic factor, and restored the markers of epithelial integrity. Remarkably, all the observed biological effects were potentiated by the co-stimulation with the two compounds and were not mediated by VD receptor expression but rather by the ERK 1/2 pathway. Altogether, the results of this study reveal the powerful synergistic anti-inflammatory activity of SF and VD and lay the foundation for future clinical assessment of their efficacy in AMD.


Assuntos
Isotiocianatos , Degeneração Macular , Estresse Oxidativo , Espécies Reativas de Oxigênio , Sulfóxidos , Vitamina D , Humanos , Degeneração Macular/metabolismo , Degeneração Macular/tratamento farmacológico , Degeneração Macular/patologia , Isotiocianatos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Sulfóxidos/farmacologia , Vitamina D/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular , Fator A de Crescimento do Endotélio Vascular/metabolismo , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Inflamação/patologia , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/patologia , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Biomarcadores/metabolismo , Interleucina-8/metabolismo
2.
J Chem Inf Model ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940754

RESUMO

Sigma-1 receptor (S1R) is involved in a large array of biological functions due to its ability to interact with various proteins and ion channels. Crystal structures of human S1R revealed the trimeric organization for which each protomer comprises the ligand binding pocket. This study applied a multistep computational procedure to develop a pharmacophore model obtained from molecular dynamics simulations of available cocrystal structures of well-known S1R ligands. Apart from the well-established positive ionizable and hydrophobic features, the obtained model included an additional specific hydrophobic feature and different excluded volumes, thus increasing the selectivity of the model as well as a more detailed determination of the distance between two essential features. The obtained pharmacophore model passed the validation test by receiver operating characteristic (ROC) curve analysis of active and inactive S1R ligands. Finally, the pharmacophoric performance was experimentally investigated through the synthesis and binding assay of new 4-phenylpiperazine-based compounds. The most active new ligand 2-(3-methyl-1-piperidyl)-1-(4-phenylpiperazin-1-yl)ethanone (3) showed an S1R affinity close to the reference compound haloperidol (Ki values of 4.8 and 2.6 nM, respectively). The proposed pharmacophore model can represent a useful tool to design and discover new potent S1R ligands.

3.
Acta Otorhinolaryngol Ital ; 44(Suppl. 1): S28-S36, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38745514

RESUMO

Objective: Management of recurrent head and neck cancer (HNC) is challenging. One option in previously irradiated patients is re-irradiation using interventional radiotherapy (IRT), the modern form of brachytherapy. Re-irradiation using IRT can be delivered as an exclusive strategy for salvage or through a postoperative or perioperative approach after salvage surgery. The aim of the present study is to analyse a bicentric Italian series focusing on the use of IRT as a re-irradiation modality and assess the resulting evidence concerning oncologic outcomes and morbidity. Methods: This is a retrospective study performed in two referral centres in Italy: Policlinico Universitario Agostino Gemelli in Rome and Azienda Ospedaliera Universitaria in Sassari. All patients who had previously received a full course of external beam RT and have been re-irradiated using high-dose-rate IRT between December 2010 and June 2023 were included. Patients were retreated either by a combination of surgery and perioperative (either endocavitary or interstitial) IRT or by exclusive interstitial IRT. Results: Thirty-four patients were included in the present series, 2 of whom underwent more than one IRT re-irradiation. Notably, no patient reported specific IRT-related toxicities. Median follow-up, excluding patients who died of HNC, was 24.5 months. Two-year local relapse-free survival was 26%, disease-specific survival 39.1%, and overall survival 36.6%. Conclusions: The present series is the largest reported experience of re-irradiation by IRT for HNC in Italy. The very low rate of toxicity confirms IRT as the safest re-irradiation modality. It is noteworthy to underline that IRT is a multidisciplinary strategy based on the close cooperation between surgeons and radiation oncologists during every phase, from the recommendation of treatment and implantation in the operating theatre, to its prescription and dose painting.


Assuntos
Braquiterapia , Neoplasias de Cabeça e Pescoço , Recidiva Local de Neoplasia , Reirradiação , Humanos , Estudos Retrospectivos , Masculino , Pessoa de Meia-Idade , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia , Feminino , Idoso , Recidiva Local de Neoplasia/radioterapia , Recidiva Local de Neoplasia/epidemiologia , Braquiterapia/métodos , Reirradiação/métodos , Resultado do Tratamento , Adulto , Itália , Idoso de 80 Anos ou mais
4.
J Clin Med ; 13(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38592157

RESUMO

Background: This study aimed to evaluate the safety and efficacy of povidone-iodine 0.6% (PVI) irrigation for preventing recurrence of stenosis after punctoplasty in patients with punctal and proximal canalicular stenosis treated using a venous catheter as a stent. Methods: Twenty patients were enrolled and divided into two groups. Group 1 received irrigation of 1 mL 0.6% PVI, while Group 2 received 1 mL of balanced salt solution (BSS). The patients underwent baseline, 15-, 30-, and 90-day assessments using the Ocular Surface Disease Index (OSDI) questionnaire, Symptoms Assessment in Dry Eye (SANDE), Schirmer I test, tear meniscus height (TMH), bulbar redness, meibography, and non-invasive breakup time (NIKBUT) through Keratograph 5M (Oculus, Germany). Results: At three months, both groups demonstrated statistically significant improvements in symptoms and ocular surface parameters. However, Group 1 showed statistically significant improvements in OSDI, SANDE scores, bulbar redness, and NIKBUT compared to Group 2. Additionally, no patients in Group 1 presented a recurrence of stenosis, while three patients in Group 2 demonstrated stenosis relapse at the end of the follow-up period. Conclusions: The application of a venous catheter and PVI 0.6% irrigations proved to be effective in treating proximal lacrimal duct stenosis, reducing the risk of recurrence and improving tear film stability, ocular discomfort symptoms, and ocular surface parameters.

5.
PLoS Genet ; 20(3): e1011186, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38483976

RESUMO

Egg activation, representing the critical oocyte-to-embryo transition, provokes meiosis completion, modification of the vitelline membrane to prevent polyspermy, and translation of maternally provided mRNAs. This transition is triggered by a calcium signal induced by spermatozoon fertilization in most animal species, but not in insects. In Drosophila melanogaster, mature oocytes remain arrested at metaphase-I of meiosis and the calcium-dependent activation occurs while the oocyte moves through the genital tract. Here, we discovered that the oenocytes of fruitfly females are required for egg activation. Oenocytes, cells specialized in lipid-metabolism, are located beneath the abdominal cuticle. In adult flies, they synthesize the fatty acids (FAs) that are the precursors of cuticular hydrocarbons (CHCs), including pheromones. The oenocyte-targeted knockdown of a set of FA-anabolic enzymes, involved in very-long-chain fatty acid (VLCFA) synthesis, leads to a defect in egg activation. Given that some but not all of the identified enzymes are required for CHC/pheromone biogenesis, this putative VLCFA-dependent remote control may rely on an as-yet unidentified CHC or may function in parallel to CHC biogenesis. Additionally, we discovered that the most posterior ventral oenocyte cluster is in close proximity to the uterus. Since oocytes dissected from females deficient in this FA-anabolic pathway can be activated in vitro, this regulatory loop likely operates upstream of the calcium trigger. To our knowledge, our findings provide the first evidence that a physiological extra-genital signal remotely controls egg activation. Moreover, our study highlights a potential metabolic link between pheromone-mediated partner recognition and egg activation.


Assuntos
Drosophila melanogaster , Drosophila , Animais , Feminino , Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Cálcio/metabolismo , Fertilização , Oócitos/metabolismo , Feromônios/genética , Feromônios/metabolismo
6.
Photodiagnosis Photodyn Ther ; 46: 104049, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38490345

RESUMO

BACKGROUND: Conventional photodynamic therapy (c-PDT) is an effective treatment for actinic keratoses (AKs) and nonmelanoma skin cancer which exploits the photosensitizing properties of methyl aminolaevulinate (MAL). Daylight photodynamic therapy (DL-PDT) is an alternative to c-PDT which does not require the application of MAL in occlusion and that is better tolerated by patients. The impact of occlusion on the efficacy of DL-PD has not been investigated by previous studies. OBJECTIVE: To compare the efficacy and tolerability of occlusive and non-occlusive DL-PDT. METHODS: We conducted a prospective intraindividual left/right comparison study. AKs of the face or scalp were marked in two symmetrical treatment areas. The two target areas were randomly assigned to DL-PDT with occlusive and non-occlusive application of MAL. The efficacy and cosmetic outcome were determined by a "blinded" investigator. RESULTS: Lesions in occluded areas showed a better response in the clearance rate of the lesions (65.5% vs 35.0 %, p < 0.001 %), and cosmetic outcome (P < 0.001). There was no difference in phototoxicity or pain between occluded and non-occluded areas. CONCLUSION: The occlusive application of MAL improves the efficacy of DL-PDT in clearing AKs and does not increase the incidence of side effects.


Assuntos
Ácido Aminolevulínico , Ceratose Actínica , Fotoquimioterapia , Fármacos Fotossensibilizantes , Ceratose Actínica/tratamento farmacológico , Humanos , Ácido Aminolevulínico/análogos & derivados , Ácido Aminolevulínico/uso terapêutico , Ácido Aminolevulínico/efeitos adversos , Fotoquimioterapia/métodos , Fotoquimioterapia/efeitos adversos , Fármacos Fotossensibilizantes/uso terapêutico , Masculino , Idoso , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Resultado do Tratamento , Luz Solar
7.
Eur J Ophthalmol ; : 11206721241235242, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38384119

RESUMO

PURPOSE: Aim of the study was to evaluate the efficacy of dexamethasone (DEX) 0.7 mg intravitreal implant in patients with diabetic macular edema (DME) and serous retinal detachment (SRD), and to study the prognostic factors on a follow up of 12 months. METHODS: Forty eyes of twenty- six patients with centre involving DME and SRD, who underwent DEX implant, were enrolled. Best-corrected visual acuity (BCVA), Swept source OCT imaging and intraocular pressure were evaluated. Central macular thickness (CMT), vitreomacular adhesion (VMA), disorganization of retinal inner layers (DRILs), hyperreflective dots (HRD), SRD and ellipsoid zone (EZ) disruption were included in the analysis at baseline and 12 months after implant. RESULTS: According to our parametric analysis, at 12 months, BVCA improvement from 48.6 ± 23.4 letters to 53.3 ± 24.5 letters was statistically significant (p = 0.04), CMT decreased from 460 ± 99.52 µm to 322.9 ± 117 µm. The presence at baseline of VMA (p = 0.01), EZ disruption (p = 0.03) and DRILs (p = 0.04), were associated with poor BCVA improvement at the end of follow-up. CONCLUSION: In conclusion, OCT biomarkers can be considered significant prognostic factors for treatment outcome in patients with DME undergoing DEX intravitreal implant.

8.
Prenat Diagn ; 44(1): 15-27, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38117025

RESUMO

OBJECTIVE: To determine the learning curve of fetal postmortem ultrasound (PMUS) and evaluate the evolution of its diagnostic performance over the past 8 years. METHODS: PMUS was performed by two fetal medicine specialists and two experts on 100 unselected fetuses of 12-38 weeks of gestation in a prospective, double-blind manner. 21 pre-defined internal structures were analyzed consecutively by the trainee alone and the expert, with a comparison of diagnosis and immediate feedback. The learning curves for examination duration, non-recognition of structures and final diagnoses were computed using cumulative summation analysis. Secondly, the expert PMUS diagnostic accuracy using autopsy as the gold standard was compared to the previously published data. RESULTS: The trainees reached expert level of PMUS at 28-36 cases for examination duration (12.1 ± 5.2 min), non-diagnostic rate (6.5%, 137/2100), and abnormality diagnosis. In a group of 33 fetuses ≥20 weeks who had an autopsy, the experts PMUS performance was improved after 8 years with a reduction of all organs non-diagnostic rate (6.5 %VS 11.4%, p < 0.01) and higher sensitivity for the heart (100% VS 40.9%, p < 0.01) and the abdomen (100%VS 56.5%, p < 0.05). CONCLUSION: PMUS offers a short learning curve for fetal medicine specialists and on-going improvement of diagnostic accuracy over time.


Assuntos
Feto , Curva de Aprendizado , Feminino , Humanos , Idade Gestacional , Estudos Prospectivos , Feto/diagnóstico por imagem , Autopsia
9.
Int J Mol Sci ; 24(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38139052

RESUMO

Vicenin-2, a flavonoid categorized as a flavones subclass, exhibits a distinctive and uncommon C-glycosidic linkage. Emerging evidence challenges the notion that deglycosylation is not a prerequisite for the absorption of C-glycosyl flavonoid in the small intestine. Capitalizing on this experimental insight and considering its biological attributes, we conducted different assays to test the anti-aggregative and antioxidant capabilities of vicenin-2 on human serum albumin under stressful conditions. Within the concentration range of 0.1-25.0 µM, vicenin-2 effectively thwarted the heat-induced HSA fibrillation and aggregation of HSA. Furthermore, in this study, we have observed that vicenin-2 demonstrated protective effects against superoxide anion and hydroxyl radicals, but it did not provide defense against active chlorine. To elucidate the underlying mechanisms, behind this biological activity, various spectroscopy techniques were employed. UV-visible spectroscopy revealed an interaction between HSA and vicenin-2. This interaction involves the cinnamoyl system found in vicenin-2, with a peak of absorbance observed at around 338 nm. Further evidence of the interaction comes from circular dichroism spectrum, which shows that the formation of bimolecular complex causes a reduction in α-helix structures. Fluorescence and displacement investigations indicated modifications near Trp214, identifying Sudlow's site I, similarly to the primary binding site. Molecular modeling revealed that vicenin-2, in nonplanar conformation, generated hydrophobic interactions, Pi-pi stacking, and hydrogen bonds inside Sudlow's site I. These findings expand our understanding of how flavonoids bind to HSA, demonstrating the potential of the complex to counteract fibrillation and oxidative stress.


Assuntos
Temperatura Alta , Albumina Sérica , Humanos , Ligação Proteica , Albumina Sérica/metabolismo , Sítios de Ligação , Albumina Sérica Humana/química , Dicroísmo Circular , Flavonoides/farmacologia , Flavonoides/metabolismo , Estresse Oxidativo , Espectrometria de Fluorescência , Termodinâmica , Simulação de Acoplamento Molecular
10.
ACS Infect Dis ; 9(11): 2141-2159, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37828912

RESUMO

The lipoteichoic acid (LTA) biosynthesis pathway has emerged as a promising antimicrobial therapeutic target. Previous studies identified the 1,3,4 oxadiazole compound 1771 as an LTA inhibitor with activity against Gram-positive pathogens. We have succeeded in making six 1771 derivatives and, through subsequent hit validation, identified the incorporation of a pentafluorosulfanyl substituent as central in enhancing activity. Our newly described derivative, compound 13, showed a 16- to 32-fold increase in activity compared to 1771 when tested against a cohort of multidrug-resistant Staphylococcus aureus strains while simultaneously exhibiting an improved toxicity profile against mammalian cells. Molecular techniques were employed in which the assumed target, lipoteichoic acid synthase (LtaS), was both deleted and overexpressed. Neither deletion nor overexpression of LtaS altered 1771 or compound 13 susceptibility; however, overexpression of LtaS increased the MIC of Congo red, a previously identified LtaS inhibitor. These data were further supported by comparing the docking poses of 1771 and derivatives in the LtaS active site, which indicated the possibility of an additional target(s). Finally, we show that both 1771 and compound 13 have activity that is independent of LtaS, extending to cover Gram-negative species if the outer membrane is first permeabilized, challenging the classification that these compounds are strict LtaS inhibitors.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Antibacterianos/química , Mamíferos , Oxidiazóis/farmacologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus
11.
Eur J Med Chem ; 260: 115771, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37657271

RESUMO

Tyrosinase, a copper-containing enzyme critical in melanin biosynthesis, is a key drug target for hyperpigmentation and melanoma in humans. Testing the inhibitory effects of compounds using tyrosinase from Agaricus bisporus (AbTYR) has been a common practice to identify potential therapeutics from synthetic and natural sources. However, structural diversity among human tyrosinase (hTYR) and AbTYR presents a challenge in developing drugs that are therapeutically effective. In this study, we combined retrospective and computational analyses with experimental data to provide insights into the development of new inhibitors targeting both hTYR and AbTYR. We observed contrasting effects of Thiamidol™ and our 4-(4-hydroxyphenyl)piperazin-1-yl-derivative (6) on both enzymes; based on this finding, we aimed to investigate their binding modes in hTYR and AbTYR to identify residues that significantly improve affinity. All the information led to the discovery of compound [4-(4-hydroxyphenyl)piperazin-1-yl](2-methoxyphenyl)methanone (MehT-3, 7), which showed comparable activity on AbTYR (IC50 = 3.52 µM) and hTYR (IC50 = 5.4 µM). Based on these achievements we propose the exploitation of our computational results to provide relevant structural information for the development of newer dual-targeting molecules, which could be preliminarily tested on AbTYR as a rapid and inexpensive screening procedure before being tested on hTYR.


Assuntos
Hiperpigmentação , Monofenol Mono-Oxigenase , Humanos , Estudos Retrospectivos , Cobre , Sistemas de Liberação de Medicamentos , Piperazina
12.
RSC Med Chem ; 14(9): 1734-1742, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37731701

RESUMO

Herein, we describe our efforts to identify sigma receptor 1 (S1R) ligands through a screening campaign on our in-house collection of piperidine/piperazine-based compounds. Our investigations led to the discovery of the potent compound 2-[4-(benzyl)-1-piperidin-1-yl]-1-4-(4-phenylpiperazin-1-yl)ethanone (1) with high affinity toward S1R (Ki value of 3.2 nM) that was comparable to reference compound haloperidol (Ki value of 2.5 nM). Functional assay revealed that compound 1 acted as S1R agonist. To decipher the binding mode of this promising S1R ligand as a starting point for further structure-based optimization, we analysed the docking pose by using a S1R-structure derived from cocrystal structures of potent ligands in complex with target protein. The computational study was enriched with molecular dynamic simulations that revealed the crucial amino acid residues that interacted with the most interesting compound 1.

13.
ChemMedChem ; 18(20): e202300330, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37694943

RESUMO

The tumor-expressed human carbonic anhydrase (hCA) isoforms hCA IX and hCA XII have been extensively studied to develop anticancer agents targeting solid tumors in combined therapy. These CA  isoforms are considered key factors in controlling tumor microenvironment (TME) of cancer lines that develop high metastatic activity. Herein, we report the discovery of potent hCA IX/hCA XII inhibitors that were disclosed through a screening campaign on an in-house collection of arylsulfonamides preliminary tested toward other hCAs. Among them, the N-(4-sulfamoylphenyl)naphthalene-2-carboxamide (12) and N-(4-sulfamoylphenyl)-3,4-dihydroisoquinoline-2(1H)-carbothioamide (15) proved to be the most intriguing hCA IX/hCA XII inhibitors displaying favourable selectivity ratios over widespread hCA I and hCA II isoforms. To explore their binding mode, we conducted docking studies that described the poses of the best inhibitors in the catalytic site of hCA IX and hCA XII, thus suggesting the privileged pattern of interactions. These structural findings might further improve the knowledge for a successful identification of new sulfonamides as adjuvant agents in cancer management.


Assuntos
Anidrases Carbônicas , Neoplasias , Humanos , Relação Estrutura-Atividade , Anidrases Carbônicas/metabolismo , Anidrase Carbônica IX/metabolismo , Antígenos de Neoplasias/metabolismo , Anidrase Carbônica I/metabolismo , Neoplasias/tratamento farmacológico , Isoformas de Proteínas/metabolismo , Inibidores da Anidrase Carbônica/química , Estrutura Molecular , Microambiente Tumoral
14.
Microorganisms ; 11(6)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37375025

RESUMO

The antifungal activity of molecules belonging to the arylsulfonamide chemotype has previously been demonstrated. Here, we screened arylsulfonamide-type compounds against a range of Candida spp. and further established the structure-activity relationship based on a "hit compound". A series of four sulfonamide-based compounds, N-(4-sulfamoylbenzyl) biphenyl-4-carboxamide (3), 2,2-diphenyl-N-(4-sulfamoylbenzyl) acetamide (4), N-(4-sulfamoylphenethyl) biphenyl-4-carboxamide (5) and 2,2-diphenyl-N-(4-sulfamoylphenethyl) acetamide (6), were tested against the American Type Culture Collection (ATCC) and clinical strains of C. albicans, C. parapsilosis and C. glabrata. Based on the fungistatic potential of prototype 3, a further subset of compounds, structurally related to hit compound 3, was synthesized and tested: two benzamides (10-11), the related amine 4-[[(4-4-((biphenyl-4-ylmethylamino)methyl) benzenesulfonamide (13) and the corresponding hydrochloride, 13.HCl. Both amine 13 and its hydrochloride salt had fungicidal effects against Candida glabrata strain 33 (MFC of 1.000 mg/mL). An indifferent effect was detected in the association of the compounds with amphotericin B and fluconazole. The cytotoxicity of the active compounds was also evaluated. This data could be useful to develop novel therapeutics for topical use against fungal infections.

15.
Int J Mol Sci ; 24(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37175649

RESUMO

Tyrosinase (EC 1.14.18.1) is implicated in melanin production in various organisms. There is a growing body of evidence suggesting that the overproduction of melanin might be related to several skin pigmentation disorders as well as neurodegenerative processes in Parkinson's disease. Based on this consideration, the development of tyrosinase inhibitors represents a new challenge to identify new agents in pharmaceutical and cosmetic applications. With the goal of identifying tyrosinase inhibitors from a synthetic source, we employed a cheap and facile preliminary assay using tyrosinase from Agaricus bisporus (AbTYR). We have previously demonstrated that the 4-fluorobenzyl moiety might be effective in interactions with the catalytic site of AbTYR; moreover, the additional chlorine atom exerted beneficial effects in enhancing inhibitory activity. Therefore, we planned the synthesis of new small compounds in which we incorporated the 3-chloro-4-fluorophenyl fragment into distinct chemotypes that revealed the ability to establish profitable contact with the AbTYR catalytic site. Our results confirmed that the presence of this fragment is an important structural feature to improve the AbTYR inhibition in these new chemotypes as well. Furthermore, docking analysis supported the best activity of the selected studied compounds, possessing higher potency when compared with reference compounds.


Assuntos
Agaricus , Monofenol Mono-Oxigenase , Monofenol Mono-Oxigenase/metabolismo , Melaninas/farmacologia , Agaricus/química , Domínio Catalítico , Inibidores Enzimáticos/química , Simulação de Acoplamento Molecular
16.
Int J Mol Sci ; 24(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36768428

RESUMO

The interaction of an equilibrium mixture of monomeric and aggregated cationic trans-5,15-bis(N-methylpyridinium-4-yl)-10,15-bis-diphenylporphine (t-H2Pagg) chloride salt with human serum albumin (HSA) has been investigated through UV/Vis absorption, fluorescence emission, circular dichroism and resonant light scattering techniques. The spectroscopic evidence reveals that both the monomeric t-H2Pagg and its aggregates bind instantaneously to HSA, leading to the formation of a tight adduct in which the porphyrin is encapsulated within the protein scaffold (S430) and to clusters of aggregated porphyrins in electrostatic interaction with the charged biomolecules. These latter species eventually interconvert into the final S430 species following pseudo-first-order kinetics. Molecular docking simulations have been performed to get some insights into the nature of the final adduct. Analogously to hemin bound to HSA, the obtained model supports favorable interactions of the porphyrin in the same 1B subdomain of the protein. Hydrophobic and van der Waals energy terms are the main contributions to the calculated ΔGbind value of -117.24 kcal/mol.


Assuntos
Porfirinas , Albumina Sérica Humana , Humanos , Albumina Sérica Humana/química , Simulação de Acoplamento Molecular , Porfirinas/química , Espectrometria de Fluorescência , Fenômenos Químicos , Dicroísmo Circular , Termodinâmica , Sítios de Ligação , Ligação Proteica
17.
Arch Pharm (Weinheim) ; 356(1): e2200383, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36250310

RESUMO

In recent years, multistep hybrid computational protocols have attracted attention for their application in the drug discovery of enzyme inhibitors. So far, there are large collections of human carbonic anhydrase (hCA) inhibitors, but only a few of them selectively inhibit the mitochondrial isoforms hCA VA and VB as potential therapeutics in obesity treatment. Most sulfonamide-based inhibitors show poor selectivity for inhibiting isoforms of therapeutic interest over ubiquitous hCA I and hCA II. Herein, we propose a combination of ligand- and structure-based approaches to generate pharmacophore models for hCA VA inhibitors. Then, we performed a virtual screening (VS) campaign on a database of commercially available sulfonamides. Finally, the in silico screening followed by docking studies suggested several "hit compounds" that demonstrated to inhibit hCA VA at a low nanomolar concentration in a stopped-flow CO2 hydrase assay. Notably, the best candidate, 2-(3,4-dihydro-2H-quinolin-1-yl)-N-(4-sulfamoylphenyl)acetamide (code name VAME-28) proved to be a potent hCA VA inhibitor (Ki value of 54.8 nM) and a more selective agent over hCA II when compared to the reference compound topiramate.


Assuntos
Anidrases Carbônicas , Humanos , Estrutura Molecular , Anidrases Carbônicas/metabolismo , Relação Estrutura-Atividade , Sulfonamidas/farmacologia , Isoformas de Proteínas , Inibidores da Anidrase Carbônica/farmacologia
18.
J Mol Struct ; 1278: None, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38312219

RESUMO

Amongst drug resistant Gram-positive bacteria, Staphylococcus aureus is a pathogen of great concern as it is the leading cause of life-threatening nosocomial and community acquired infections which are often associated with implanted medical devices. The biosynthesis of lipotheicoic acid (LTA) by S. aureus has been recognized as a promising antibacterial target, owing its critical role in the growth and survival of Gram-positive bacteria. Here we report for the first time the chemical synthesis and characterisation of an oxadiazole based compound (1771), previously described as an inhibitor of LTA biosynthesis by targeting Lta synthase enzyme (LtaS). To investigate its controversial mode of action, we also performed molecular docking studies, which indicated that 1771 behaves as a competitive inhibitor against LtaS. We also synthesised and evaluated the antimicrobial activity of 1771 metabolites which we have identified from its decomposition in mouse serum, proving that the biological activity was caused by intact 1771.

19.
Int J Mol Sci ; 23(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36499173

RESUMO

α-Synuclein (α-Syn) aggregates are implicated in Parkinson's disease (PD), so inhibitors of α-Syn aggregation have been intensively explored. It has been demonstrated that small molecules might be able to reduce α-Syn aggregation in fibrils, thus exerting neuroprotective effects in models of PD. To expand our knowledge about the structural requirements for blocking the recognition process into the oligomeric assembly of α-Syn aggregates, we performed a ligand-based virtual screening procedure using two well-known α-Syn aggregation inhibitors, SynuClean-D and ZPD-2, as query compounds. A collection of thirty-four compounds bearing distinct chemical functionalities and mutual chemical features were studied in a Th-T fluorescence test, thus identifying 5-(2,6-dinitro-4-(trifluoromethyl)benzyl)-1-methyl-1H-tetrazole (named MeSC-04) as a potent α-Syn amyloid formation inhibitor that demonstrated similar behavior when compared to SynuClean-D in the thioflavin-T-monitored kinetic assays, with both molecules reducing the number and size of amyloid fibrils, as evidenced by electron microscopy. Molecular modeling studies suggested the binding mode of MeSC-04 through the identification of putative druggable pockets on α-syn fibrils and a subsequent consensus docking methodology. Overall, this work could furnish new insights in the development of α-Syn amyloid inhibitors from synthetic sources.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , Amiloide/metabolismo , Ligantes , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Proteínas Amiloidogênicas
20.
J Pers Med ; 12(10)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36294725

RESUMO

(1) Background: Endoscopy and morphological imaging are the mainstay of the diagnostic work up of laryngeal squamous cell carcinomas (LSCCs), which can be integrated in a multidisciplinary discussion to obtain a shared pretreatment staging. (2) Methods: A retrospective evaluation of patients, managed at a tertiary university hospital in Italy and submitted to major laryngeal surgery, has been performed. Four different stagings have been defined and compared: epTN (based on endoscopy and physical ENT examination); radTN (based on CT scan); cTN (based on multidisciplinary integration of the two above); pTN based on pathology on surgical samples. Oncological outcomes have been assessed. (3) Results: Three-year relapse free and disease specific survival were 88% and 92.5%, respectively, without significant differences between partial surgeries (n = 13) and total laryngectomies (n = 32). As for the pretreatment staging, and in particular the T classification, the cTN has been revealed as more reliable than epTN and radTN alone in predicting the final pT (Cohen kappa coefficient: 0.7 for cT, 0.44 for radT, 0.32 for epT). In the partial surgery group, we did not record any positive margin nor local recurrence, with a 100% overall and disease-specific survival. (4) Conclusions: The multidisciplinary approach is fundamental in the definition of the primary lesion in LSCC, in particular in order to safely perform surgical preservation of laryngeal function, which is associated with a higher laryngectomy-free survival than irradiation but to a lower salvageability in case of recurrence.

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