Repository logo
 

Search Results

Now showing 1 - 4 of 4
  • Naringenin-4'-glucuronide as a new drug candidate against the COVID-19 Omicron variant: a study based on molecular docking, molecular dynamics, MM/PBSA and MM/GBSA
    Publication . Cobre, Alexandre de Fátima; Neto, Moisés Maia; Melo, Eduardo Borges de; Fachi, Mariana Millan; Ferreira, Luana Mota; Tonin, Fernanda; Pontarolo, Roberto
    This study aimed to identify natural bioactive compounds (NBCs) as potential inhibitors of the spike (S1) receptor binding domain (RBD) of the COVID-19 Omicron variant using computer simulations (in silico). NBCs with previously proven biological in vitro activity were obtained from the ZINC database and analyzed through virtual screening, molecular docking, molecular dynamics (MD), molecular mechanics/Poisson-Boltzmann surface area (MM/PBSA), and molecular mechanics/generalized Born surface area (MM/GBSA). Remdesivir was used as a reference drug in docking and MD calculations. A total of 170,906 compounds were analyzed. Molecular docking screening revealed the top four NBCs with a high affinity with the spike (affinity energy <-7 kcal/mol) to be ZINC000045789238, ZINC000004098448, ZINC000008662732, and ZINC000003995616. In the MD analysis, the four ligands formed a complex with the highest dynamic equilibrium S1 (mean RMSD <0.3 nm), lowest fluctuation of the complex amino acid residues (RMSF <1.3), and solvent accessibility stability. However, the ZINC000045789238-spike complex (naringenin-4'-O glucuronide) was the only one that simultaneously had minus signal (-) MM/PBSA and MM/GBSA binding free energy values (-3.74 kcal/mol and -15.65 kcal/mol, respectively), indicating favorable binding. This ligand (naringenin-4'-O glucuronide) was also the one that produced the highest number of hydrogen bonds in the entire dynamic period (average = 4601 bonds per nanosecond). Six mutant amino acid residues formed these hydrogen bonds from the RBD region of S1 in the Omicron variant: Asn417, Ser494, Ser496, Arg403, Arg408, and His505. Naringenin-4'-O-glucuronide showed promising results as a potential drug candidate against COVID-19. In vitro, and preclinical studies are needed to confirm these findings.
  • Novel COVID-19 biomarkers identified through multi-omics data analysis: N-acetyl-4-O-acetylneuraminic acid, N-acetyl-L-alanine, N-acetyltriptophan, palmitoylcarnitine, and glycerol 1-myristate
    Publication . Cobre, Alexandre de Fátima; Alves, Alexessander Couto; Gotine, Ana Raquel; Domingues, Karime Zeraik; Lazo, Raul Edison; Ferreira, Luana Mota; Tonin, Fernanda; Pontarolo, Roberto
    This study aims to apply machine learning models to identify new biomarkers associated with the early diagnosis and prognosis of SARS-CoV-2 infection. Plasma and serum samples from COVID-19 patients (mild, moderate, and severe), patients with other pneumonia (but with negative COVID-19 RT-PCR), and healthy volunteers (control) from hospitals in four different countries (China, Spain, France, and Italy) were analyzed by GC-MS, LC-MS, and NMR. Machine learning models (PCA and PLS-DA) were developed to predict the diagnosis and prognosis of COVID-19 and identify biomarkers associated with these outcomes. A total of 1410 patient samples were analyzed. The PLS-DA model presented a diagnostic and prognostic accuracy of around 95% of all analyzed data. A total of 23 biomarkers (e.g., spermidine, taurine, L-aspartic, L-glutamic, L-phenylalanine and xanthine, ornithine, and ribothimidine) have been identified as being associated with the diagnosis and prognosis of COVID-19. Additionally, we also identified for the first time five new biomarkers (N-Acetyl-4-O-acetylneuraminic acid, N-Acetyl-L-Alanine, N-Acetyltriptophan, palmitoylcarnitine, and glycerol 1-myristate) that are also associated with the severity and diagnosis of COVID-19. These five new biomarkers were elevated in severe COVID-19 patients compared to patients with mild disease or healthy volunteers. The PLS-DA model was able to predict the diagnosis and prognosis of COVID-19 around 95%. Additionally, our investigation pinpointed five novel potential biomarkers linked to the diagnosis and prognosis of COVID-19: N-Acetyl-4-O-acetylneuraminic acid, N-Acetyl-L-Alanine, N-Acetyltriptophan, palmitoylcarnitine, and glycerol 1-myristate. These biomarkers exhibited heightened levels in severe COVID-19 patients compared to those with mild COVID-19 or healthy volunteers.
  • Accuracy of COVID-19 diagnostic tests via infrared spectroscopy: a systematic review and meta-analysis
    Publication . Cobre, Alexandre de Fátima; Fachi, Mariana Millan; Domingues, Karime Zeraik Abdalla; Lazo, Raul Edison Luna; Ferreira, Luana Mota; Tonin, Fernanda; Pontarolo, Roberto
    This study aims to synthesize the evidence on the accuracy parameters of COVID-19 diagnosis methods using infrared spectroscopy (FTIR). A systematic review with searches in PubMed and Embase was performed (September 2023). Studies reporting data on test specificity, sensitivity, true positive, true negative, false positive, and false negative using different human samples were included. Meta-analysis of accuracy estimates with 95 % confidence intervals and area under the ROC Curve (AUC) were conducted (Meta-Disc 1.4.7). Seventeen studies were included - all of them highlighted regions 650-1800 cm-1 and 2300-3900 cm-1 as most important for diagnosing COVID-19. The FTIR technique presented high sensitivity [0.912 (95 %CI, 0.878-0.939), especially in vaccinated [0.959 (CI95 %, 0.908-0.987)] compared to unvaccinated [0.625 (CI95 %, 0.584-0.664)] individuals for COVID-19. Overall specificity was also high [0.886 (95 %CI, 0.855-0.912), with increased rates in vaccinated [0.884 (CI95 %, 0.819-0.932)] than in unvaccinated [0.667 (CI95 %, 0.629-0.704)] patients. These findings reveal that FTIR is an accurate technique for detecting SARS-CoV-2 infection in different biological matrices with advantages including low cost, rapid and environmentally friendly with minimal preparation analyses. This could lead to an easy implementation of this technique in practice as a screening tool for patients with suspected COVID-19, especially in low-income countries.
  • Next-generation wound care: a scoping review on probiotic, prebiotic, synbiotic, and postbiotic cutaneous formulations
    Publication . Machado, Patrícia; Ribeiro, Felipe Neme; Giublin, Fernanda Wroblevski; Mieres, Naomi Gerzvolf; Tonin, Fernanda; Pontarolo, Roberto; Sari, Marcel Marcondes; Lazo, Raul Luna; Ferreira, Luana Mota
    Background/Objectives: Chronic wounds represent a significant socioeconomic burden, affecting 1–2% of the global population. Wound healing is a complex process involving inflammation, cell proliferation, and tissue remodeling, but factors such as infections, diabetes, aging, and poor nutrition can impair recovery, leading to chronic wounds. Given these challenges, researchers have explored topical probiotics, synbiotics, and postbiotics as alternative strategies. Strains like Lactobacillus and Bifidobacterium contribute to skin restoration by producing antimicrobial, anti-inflammatory, and immunomodulatory compounds, offering a novel approach to cutaneous restoration. Our study aims to address the potential effects of topical probiotic, synbiotic, and postbiotic formulations for wound healing applications by means of a broad scoping review and evidence-gap mapping. Methods: A systematic literature search of preclinical studies (in vitro and in vivo) was performed in PubMed, Scopus, and Web of Science (January 2025), yielding 3052 articles after duplicates removal, of which 44 met the inclusion criteria. Results: These studies were published between 1986 and 2024, mostly by China (27.3%) and Iran (25.0%). Probiotics were frequently evaluated among the studies included (47.7%) (with Lactobacillus plantarum being the most assessed strain), followed by postbiotics (36.4%) (with predominant use of cell-free supernatants) and synbiotics (15.9%) (especially fructooligosaccharides). Dosage forms included gels (44.4%), films (15.6%), and ointments (13.3%). Conclusions: Most studies indicate that probiotics, synbiotics, and postbiotics have antimicrobial and anti-inflammatory properties, while promoting angiogenesis, tissue regeneration, and skin barrier restoration. The use of different delivery systems may additionally enhance therapeutic outcomes by accelerating wound closure, reducing bacterial load, and modulating immune response. However, methodological limitations in animal studies highlight the need for greater experimental rigor. Further robust clinical trials are essential to confirm efficacy and safety before clinical application of these formulations.