Molecules

The aim of this study was to obtain and characterize grape seed extract and to demonstrate its potential immunomodulatory properties in the autoimmune disease systemic lupus erythematosus (SLE). A Syrah grape seed extract was obtained using 70% aqueous ethanol, magnetic stirrer, 3 h. The obtained extracts were concentrated by vacuum evaporation and dryer at 40 °C. The total phenolic content (TPC), the total amount of flavonoids (TF) and procyanidins (PC), and the antioxidant (AO) capacity of the extract were determined by spectrophotometric methods. The individual composition of the extract was demonstrated by the high-performance liquid chromatography (HPLC) method. The effect of grape seed extract (GSE) on peripheral blood mononuclear cells (PBMC) from healthy donors and patients with SLE was studied to compare Th1 and Th2 subsets and their expression of key activation markers—CD25 and HLA-DR. PBMC were cultured in the presence or absence of GSE, and the effects on Th1 and Th2 cells were analyzed by flow cytometry. GSE treatment increased the proportion of Th1 cells in both healthy individuals and SLE patients. In addition, a significant upregulation of the late activation marker HLA-DR was observed on Th1 cells obtained from patients with systemic lupus erythematosus (SLE). No significant effects were found on Th2 cell populations. These findings indicate that GSE can stimulate Th1-mediated immune responses in SLE, proving its potential immunomodulatory properties beyond its known antioxidant effects.

Bromodomain-containing protein 9 (BRD9) belongs to the non-canonical BAF chromatin remodeling complex and represents a relevant therapeutic target in pathologies featuring dysregulated epigenetic control. The absence of clinically validated inhibitors and the need for diversified chemical entities highlight the interest in identifying new scaffolds targeting this protein. In this study, Saturation Transfer Difference Nuclear Magnetic Resonance (STD NMR) was employed to assess its suitability for characterizing BRD9–ligand interactions within a fragment-based discovery framework. STD NMR conditions were first optimized using the known BRD9 ligand 1, verifying the presence of interaction signals. A pharmacophore-based virtual screening campaign was then performed using libraries of commercially available fragments, leading to the selection of a novel isatin derivative, i.e., compound 2, whose binding was demonstrated in AlphaScreen assays. STD NMR experiments provided epitope mapping consistent with the predicted binding mode, thus supporting the stability of the interaction in solution. Moreover, a competitive STD experiment demonstrated displacement of 2 by a reference ligand, confirming the binding within the canonical BRD9 pocket. Overall, this study establishes STD NMR as a reliable approach for probing BRD9–ligand interactions and for the identification and validation of BRD9-targeting scaffolds suitable for future structure-guided optimization.

Cyclodextrins (CDs) are cyclic oligosaccharides composed of α(1 → 4) linked glucose units, which are widely used as solubilizers and stabilizers in the food, pharmaceutical and cosmetic industries. Among the CDs, γ-CD has attracted much attention due to its larger hydrophobic cavity and higher solubility. However, the industrial production of γ-CD is limited by lack of suitable enzymes and production process shortcomings. In this study, various strategies of improving heterologous enzyme production and optimization of the starch conversion process were applied to increase the production of γ-CD. A γ-cyclodextrin glucanotransferase with good product specificity from Bacillus sp. FJAT-44876 (BFγ-CGTase) and a liquefying β-CGTase from Bacillus sp. 1011 (Bsβ-CGTase) were successfully secreted by Pichia pastoris. After codon optimization and using the one-factor-at-a-time (OFAT) principle to improve the fermentation, the yield of recombinant BFγ-CGTase was increased 13.3 times to 463 U/L. Next a process was established involving Bsβ-CGTase-assisted starch liquefaction and simultaneous pullulanase debranching and BFγ-CGTase production of γ-CD. The yield of γ-CD increased by 17.67% via optimizing the amounts of BFγ-CGTase and BtPul used for the reaction. Overall, combination of the various improvements provided a new process for efficient preparation of γ-CD.