The species of the genus Tabernaemontana have a long tradition of use in different pathologies of infectious origins; the antibacterial, antifungal, and antiviral effects related to the control of the pathologies where the species of this genus are used, have been attributed to the indole monoterpene alkaloids, mainly those of the iboga type. There are more than 1000 alkaloids isolated from different species of Tabernaemontana and other genera of the Apocynaceae family, several of which lack studies related to antibacterial activity. In the present study, four monoterpene indole alkaloids were isolated from the seeds of the species Tabernaemontana cymosa Jacq, namely voacangine (1), voacangine-7-hydroxyindolenine (2), 3-oxovoacangine (3), and rupicoline (4), which were tested in an in vitro antibacterial activity study against the bacteria S. aureus, sensitive and resistant to methicillin, and classified by the World Health Organization as critical for the investigation of new antibiotics. Of the four alkaloids tested, only voacangine was active against S. aureus, with an MIC of 50 µg/mL. In addition, an in silico study was carried out between the four isolated alkaloids and some proteins of this bacterium, finding that voacangine also showed binding to proteins involved in cell wall synthesis, mainly PBP2 and PBP2a.

Background Atopic dermatitis (AD) is a chronic inflammatory skin condition that has a significant impact on quality of life. The immune response and allergy symptoms in AD are triggered by the recognition of specific allergens by IgE antibodies. Cross-reactivity can lead to auto-IgE responses, potentially worsening AD symptoms. Our research aimed to enhance our understanding of allergenic sources, including A. fumigatus, and their role in AD. We focused on molecular mimicry between human AQP3 and A. fumigatus aquaporin. Methods In our in-silico analysis, we compared the amino acid sequences of human aquaporin 3 (AQP3) and A. fumigatus aquaporin with 25 aquaporins from various allergenic sources, sourced from the UniProt and NCBI databases. Phylogenetic relationship analysis and homology-based modeling were conducted. We identified conserved antigenic regions located within the 3D structures. Results The global identity levels among the studied aquaporins averaged 32.6%. One antigenic site exhibited a remarkable local region, with a conserved identity of 71.4%. We categorized the aquaporins into five monophyletic clades (A–E), with group B showing the highest identity (95%), including six mammalian aquaporins, including AQP3. When comparing A. fumigatus aquaporins, the highest identity was observed with Malassezia sympodialis at 35%. Both human and A. fumigatus aquaporins have three linear and three discontinuous epitopes. Conclusions We identified potential linear and conformational epitopes of AQP3, indicating a possible molecular mimicry between humans and A. fumigatus aquaporins. This suggests autoreactivity and potential cross-reactivity, although further validation using in vitro and in vivo experiments is required.

Background Atopic dermatitis (AD) is a chronic inflammatory skin condition that has a significant impact on quality of life. The immune response and allergy symptoms in AD are triggered by the recognition of specific allergens by IgE antibodies. Cross-reactivity can lead to auto-IgE responses, potentially worsening AD symptoms. Our research aimed to enhance our understanding of allergenic sources, including A. fumigatus, and their role in AD. We focused on molecular mimicry between human AQP3 and A. fumigatus aquaporin. Methods In our in-silico analysis, we compared the amino acid sequences of human aquaporin 3 (AQP3) and A. fumigatus aquaporin with 25 aquaporins from various allergenic sources, sourced from the UniProt and NCBI databases. Phylogenetic relationship analysis and homology-based modeling were conducted. We identified conserved antigenic regions located within the 3D structures. Results The global identity levels among the studied aquaporins averaged 32.6%. One antigenic site exhibited a remarkable local region, with a conserved identity of 71.4%. We categorized the aquaporins into five monophyletic clades (A–E), with group B showing the highest identity (95%), including six mammalian aquaporins, including AQP3. When comparing A. fumigatus aquaporins, the highest identity was observed with Malassezia sympodialis at 35%. Both human and A. fumigatus aquaporins have three linear and three discontinuous epitopes. Conclusions We identified potential linear and conformational epitopes of AQP3, indicating a possible molecular mimicry between humans and A. fumigatus aquaporins. This suggests autoreactivity and potential cross-reactivity, although further validation using in vitro and in vivo experiments is required.

Esomeprazole (ESO) is susceptible to degradation under stress conditions, making polymer selection important for stable solid dispersions. This study evaluated ESO compatibility with five polymers: three grades of hydroxypropyl methylcellulose acetate succinate (HPMCAS-LMP, HPMCAS-MMP, and HPMCAS-HMP), hydroxypropyl methylcellulose phthalate (HPMCP-55), and methacrylic acid–ethyl acrylate copolymer (1:1; Eudragit^® L100-55). Esomeprazole, polymers, and binary mixtures were stored at room temperature and subjected to forced thermal degradation at 60 °C for 16 days. Spectral changes were assessed by visual inspection and attenuated total reflectance–Fourier transform infrared (ATR-FTIR) spectroscopy using the fractional change index (FCI), normalized root-mean-square deviation (NRMSD), and relative maximum spectral difference (relative Max Δ). Density functional theory (DFT) calculations examined interaction energies, non-covalent interactions (NCIs), frontier molecular orbitals, and HOMO–LUMO-based reactivity descriptors. Combining quantitative ATR-FTIR analysis under thermal stress with DFT provides complementary experimental and molecular-level insights into ESO–polymer interactions, including an experimental comparison of three HPMCAS grades. The ESO–HPMCAS-MMP mixture showed the smallest spectral deviations. DFT indicated favorable interactions and relatively low chemical reactivity for the modeled ESO–HPMCAS complex. These findings support the preliminary consideration of HPMCAS-MMP for further formulation studies, although additional evidence is needed to establish comparative chemical compatibility and stability.

. Objective: To analyze the phylogenetic relationships and molecular mimicry of Cit s 2 and other plant profilins. Methods: Online bioinformatics tools, including BLASTP, PRALINE, and MEGA, were used for multiple alignments and phylogenetic analysis. A 3D homology model of Cit s 2 was predicted using MODELLER. The best model was selected based on the Maestro model scoring option. Conserved regions between Cit s 2 and other profilins were mapped onto the 3D model, and antigenic regions were predicted using the ElliPro server. Results: The amino acid sequence of Cit s 2 (Uniprot code: P84177) was compared with 30 other profilins from different allergenic sources. The highest identity was observed with Cucumis melo (99%), followed by Prunus persica (98%) and Malus domestica (92%). Highly conserved antigenic regions were observed in the predicted 3D model. Seven linear epitopes and six discontinuous epitopes were identified in Cit s 2. Conclusion: Highly conserved antigenic regions were observed in the predicted 3D model of Cit s 2, suggesting potential cross-reactivity between Cit s 2 and other profilins. Further studies are needed to analyze these findings in more detail.