Institute of Biomolecular Chemistry

Sanna D., Fadda A.

Myrtle oil extracted from the spent berries of myrtle liqueur production, using 2-methyltetrahydrofuran, was used to increase the oxidative stability of sunflower oil (SFO). Three blending ratios (5%, 10%, and 15% w/w) and the SFO without any addition were subjected to forced aging conditions at 70 °C for 21 days. The changes in peroxide value (PV), p-anisidine value (AV), total oxidation value (totox), and conjugated dienes and trienes were evaluated during forced aging. The oxidative stability of the blends was also assessed by the spin trapping method coupled with Electron Paramagnetic Resonance spectroscopy. Myrtle oil at 5% provided the best results, increasing the oxidative stability of SFO by reducing the PV and slowing the onset of secondary oxidation products, as measured by the AV and conjugated trienes. The 15% blend, despite its high levels of PV, AV, conjugated dienes, and trienes during storage, protects SFO from oxidation. The blends of SFO with unconventional oils, like myrtle oil, could represent a sustainable approach to increase its oxidative stability during storage.

Maramai S., Mugnaini C., Paolino M., Schiano Moriello A., De Petrocellis L., Corelli F., Aiello F., Brizzi A.

Due to its central role in pain, inflammation, and related disorders, the Transient Receptor Potential (TPR) Vanilloid Type-1 (TRPV1) ion channel represents an attractive target for the development of novel antinociceptive and anti-inflammatory agents. Capsaicin, the natural component of chili peppers, is one of the most investigated agonists of this receptor. Several modifications of its structure have been attempted, aiming at finding TRPV1 agonists with improved characteristics, but, to date, no capsaicin-derived agents have reached the market. Based on our previous knowledge of the design and synthesis of TRPV1 agonists, in this paper we propose two small series of indole-2-carboxamides as novel and selective agonists for this ion channel. The newly developed compounds have been structurally characterized and tested in vitro for their ability to modulate TRPV1, in terms of efficacy, potency (EC50), and desensitization (IC50) properties. For the most promising derivatives, selectivity over the TRP ankyrin-1 (TRPA1) channel has been reported. From our study, compound 6g arose as a promising candidate for further evaluation, also in correlation with its in silico-predicted drug-like properties.

Beiranvandi M., Akbari N., Ahmadi A., Mumivand H., Nazarian Firouzabadi F., Argento S.

Satureja rechingeri is a valuable medicinal plant, but its growth can be significantly impacted by water deficit stress. To investigate the effects of biochar (BC) and hydroretentive polymers (HPs) on various eco-physiological traits of savory under a water deficit, an experiment was conducted over two consecutive cropping seasons (2017–2019). A randomized complete block design with a split-plot factorial arrangement and three replications was used. The treatments consisted of three levels of irrigation (95 ± 5, 75 ± 5, and 55 ± 5% FC), which were applied to the main plots, and combinations of two levels of biochar and two levels of HPs, which were applied to subplots. The results show that a water deficit reduced the relative water content (RWC), chlorophyll content, and dry matter yield of the shoots. Furthermore, the activity of catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), and malondialdehyde (MDA) increased in two-year-old plants. The MDA content significantly decreased by 15.6% in the second year compared to in the first year under a water deficit. The application of HPs caused a decrease of 26.4%, 32.5%, and 27.5% in POD, CAT, and APX enzyme activities, respectively, compared to their control levels. In the biochar treatment, there was a significant reduction in the activity of POD, APX, and CAT in the leaves.

Nani M., De Cicco P., Cattaneo F., Petrosino S., Tropeano F.P., Miraglia M., Pagano E., Rinaldi M.M., Izzo A.A., Romano B.

Abstract Background Intestinal fibrosis, a frequent complication of inflammatory bowel disease, is characterized by stricture formation with no pharmacological treatment to date. N-acylethanolamine acid amidase (NAAA) is responsible for the hydrolysis of acylethanolamides (AEs, eg, palmitoylethanolamide and oleoylethanolamide). Here, we investigated NAAA and AE signalling in gut fibrosis. Methods NAAA and AE signalling were evaluated in human intestinal specimens from patients with stenotic Crohn’s disease (CD). Gut fibrosis was induced by 2,4,6-trinitrobenzenesulfonic acid, monitored by colonoscopy, and assessed by qRT-PCR, histological analyses, and confocal microscopy. Immune cells in mesenteric lymph nodes were analysed by FACS. Colonic fibroblasts were cultured in conditioned media derived from polarized or non-polarized bone marrow-derived macrophages (BMDMs). IL-23 signalling was evaluated by qRT-PCR, ELISA, FACS, and western blot in BMDMs and in lamina propria CX3CR1+ cells. Results In ileocolonic human CD strictures, increased transcript expression of NAAA was observed with a decrease in its substrates oleoylethanolamide and palmitoylethanolamide. NAAA inhibition reduced intestinal fibrosis in vivo. More in-depth studies revealed modulation of the immune response related to IL-23 following NAAA inhibition. The antifibrotic actions of NAAA inhibition are mediated by Mφ and M2 macrophages that indirectly affect fibroblast collagenogenesis. NAAA inhibitor AM9053 normalized IL-23 signalling in BMDMs and in lamina propria CX3CR1+ cells. Conclusion Our findings provide new insights into the pathophysiological mechanism of intestinal fibrosis and identify NAAA as a promising target for the development of therapeutic treatments to alleviate CD-related fibrosis.

Caruso A., Tommonaro G., Vassallo A., Paris D., Monné M., Catalano A., Sinicropi M.S., Saturnino C.

ABSTRACTAlzheimer's disease is a neurodegenerative chronic disease with a severe social and economic impact in the societies, which still lacks an efficient therapy. Several pathophysiological events (β‐amyloid [Aβ] deposits, τ‐protein aggregation, loss of cholinergic activity, and oxidative stress) occurs in the progression of the disease. Therefore, the search for efficient multi‐targeted agents for the treatment of Alzheimer's disease becomes indispensable. In this paper we evaluated the AChE inhibition by Ellman's method and antioxidant activity by DPPH assay of nine synthetic compounds: two hydroxy‐benzene derivatives (1 and 2), three bis‐thioureidic derivatives (3–5), two imidazole derivatives (6 and 7), and two phenylacetamide derivatives (8 and 9). The compound 2, (3s,5s,7s)‐adamantan‐1‐yl 4‐(((E)‐2,5‐dihydroxybenzylidene)amino)benzoate, exhibited the best antioxidant activity (30.00 ± 1.05 μM eq Trolox) and compound 4 showed the highest AChE inhibition value (IC50 [μM] 8.40 ± 0.32). In the search for a compound showing combined activities (antioxidant and AChE inhibition), the compound 4, octane‐1,8‐diyl‐bis‐S‐amidinothiourea dihydrobromide, (19.02 ± 1.52 μM eq Trolox; IC50 [μM] 8.40 ± 0.32) was chosen to carry out a molecular docking study. The results showed that compound 4 has the ability to bind the active site of acetylcholinesterase with considerable affinity (estimated binding energies of −8.5 kcal/mol). All data indicate that compound 4 has the potential to be further investigated as a possible candidate in the Alzheimer's disease treatment.

Dinda R., Garribba E., Sanna D., Crans D.C., Costa Pessoa J.

Ogbodo J.O., Egba S.I., Ikechukwu G.C., Paul P.C., Mba J.O., Ugwu O.P., Ezike T.C.

Volatile organic compounds (VOCs) can impact the actions of drugs due to their effects on drug receptors and the activities of enzymes involved in various metabolic processes, especially those relating to gene regulation. They can disrupt cellular functions and potentially affect human drug metabolism and utilization receptors. They mimic or inhibit the actions of endogenous ligands, leading to carcinogenesis, neurotoxicity, endocrine disruption, and respiratory disorders. Chronic exposure to VOCs due to human occupation can lead to an increased generation of reactive oxygen species (ROS), which could lead to oxidative stress and damage to lipids, affecting the formation and proper functioning of gene regulation, enzyme activity, and cell membranes. The presence of oxidative stress could interfere with drug activity and potentially impact the body’s ability to process and utilize drugs effectively. This is because drugs such as antioxidant drugs play an essential role in cell protection against oxidative damage. Therefore, disruptions in their metabolism could distort the overall health condition through the breakdown of antioxidant defense mechanisms. In this study, the aim is to assess the effect of VOC exposure on drug receptors and the way forward in designing and maintaining optimal drug activity for workers’ overall well-being.

Canessa M., Bo M., Cau A., Corriero G., Follesa M.C., Mercurio M., Sandulli R., Villani G., Bavestrello G.

Costanzo G., Cosentino G., Grasso M., Patamia V., Zuccalà S., Coco A., Novello E., Al-Khrasani M., Morrone R., Pitari G.M., Amata E., Marrazzo A., Rescifina A., Pasquinucci L., Parenti C.

Compound 7 exhibited high σ1R affinity and selectivity and produced a potent antinociceptive effect in a mouse model of inflammatory pain. Molecular modeling studies were performed to analyze its key interactions with σ1R.

Dias I., Bon L., Banas A., Chavarria D., Borges F., Guerreiro-Oliveira C., Cardoso S.M., Sanna D., Garribba E., Chaves S., Santos M.A.

The multifaceted nature of the neurodegenerative diseases, as Alzheimer's disease (AD) and Parkinson's disease (PD) with several interconnected etiologies, and the absence of effective drugs, led herein to the development and study of a series of multi-target directed ligands (MTDLs). The developed RIV-IND hybrids, derived from the conjugation of an approved anti-AD drug, rivastigmine (RIV), with melatonin analogues, namely indole (IND) derivatives, revealed multifunctional properties, by associating the cholinesterase inhibition of the RIV drug with antioxidant activity, biometal (Cu(II), Zn(II), Fe(III)) chelation properties, inhibition of amyloid-β (Aβ) aggregation (self- and Cu-induced) and of monoamine oxidases (MAOs), as well as neuroprotection capacity in cell models of AD and PD. In particular, two hybrids with hydroxyl-substituted indoles (5a2 and 5a3) could be promising multifunctional compounds that inspire further development of novel anti-neurodegenerative drugs.

Prófumo A., Avila C., Cutignano A.

The waters around the western Antarctic Peninsula are experiencing fast warming due to global change, being among the most affected regions on the planet. This polar area is home to a large and rich community of benthic marine invertebrates, such as sponges, tunicates, corals, and many other animals. Among the sponges, the bright yellow Dendrilla antarctica is commonly known for using secondary diterpenoids as a defensive mechanism against local potential predators. From the dichloromethane extract of sponge samples from Deception Island collected in January 2023, we isolated a novel derivative with an unusual β-lactone diterpene skeleton here named dendrillolactone (1), along with seven previously described diterpenes, including deceptionin (2), a gracilane norditerpene (3), cadlinolide C (4), a glaciolane norditerpene (5), membranolide (6), aplysulphurin (7), and tetrahydroaplysulphurine-1 (8). Here, we also report our studies on the changes in the chemical arsenal of this sponge by slow temperature increase in aquaria experiments. Despite being a species capable of inhabiting volcanically active areas, with frequent water temperature fluctuations due to the existing fumaroles, the results show that diterpenes such as deceptionin, cadlinolide C, membranolide, and tetrahydroaplysulphurin-1 seem to be susceptible to the temperature increase, resulting in a trend to higher concentrations. However, temperatures above 4 °C severely affected sponge metabolism, causing its death much earlier than expected. Further research on the roles of these natural products in D. antarctica and their relationship to the sponge’s resilience to environmental changes should help to better understand the defensive mechanisms of Antarctic marine benthos in the context of global change.

Buzzanca C., D’Amico A., Pistorio E., Di Stefano V., Melilli M.G.

Functional carob beverages have recently attracted consumer attention as a natural and sustainable alternative due to their excellent nutritional profile and associated health benefits. Derived from the pods of the carob tree (Ceratonia siliqua L.), which thrives in Mediterranean regions, these beverages are naturally sweet, caffeine-free, and rich in bioactive compounds, including polyphenols, dietary fiber, and essential minerals. This review highlights the nutritional composition of carob beverages, noting their high fiber content, antioxidant capacity, and lack of stimulating alkaloids, making them an ideal option for health-conscious consumers. The manufacturing processes, phytochemical properties, and sensory qualities of carob beverages are discussed, along with their potential roles in promoting digestive, cardiovascular, and metabolic health. The growing interest in carob reflects broader trends in sustainable food systems and plant-based nutrition, positioning carob beverages as a promising choice in the functional beverage industry.

Rancan M., Bisello A., Carlotto S., Basagni A., Schiesari R., Mondal P.K., Formaggio F., Santi S.

AbstractThis work reports single‐crystal X‐ray diffraction (XRD), Scanning Tunneling Microscopy (STM), and quantum mechanics calculations of the 310‐helical peptide Z‐(Aib)2‐L–Dap(Boc)‐Aib‐NHiPr (Aib, α‐aminoisobutyric acid; Dap, 2,3‐diaminopropionic acid; Z, benzyloxycarbonyl; Boc, t‐butoxycarbonyl). The peptide forms a double‐helical superstructure, studied by XRD and STM. Such architecture is rare in short peptides. Here, we show, by combining XRD and STM that this intriguing conformational feature is not driven by crystal packing; rather, it is an intrinsic property of this peptide. Indeed, the double helix is clearly detected also by STM, where crystal packing cannot be invoked. XRD reveals that intermolecular H‐bonds stabilize two left‐handed supra‐helices (tertiary structure) that develop around a 6‐fold screw axis. Then, two supra‐helices are intertwined in a quaternary structure as a left‐handed, double supra‐helix, where C−H⋯π interactions play a crucial role. STM images show the formation of long, isolated “necklaces” (>110 nm). They are of left and right helical handedness. Their size agrees with the XRD finding. DFT calculations allowed us to weigh the contribution of the different intermolecular interactions in the two single supra‐helices and the supramolecular double‐helix. Interestingly, we were able to conclude that the contribution of the C−H⋯π interactions to the binding energies is close to 50 %.

Dettori M.A., Ugone V., Fabbri D., Carta P.

In this study, UV-induced (E)-to-(Z) geometrical isomerizations of the curcumin degradation product (E)-dehydrozingerone, along with curcumin-inspired (E)-O-methylated dehydrozingerone and their corresponding C2-symmetric dimers, were investigated. All compounds produced corresponding (Z) isomers in varying yields upon UV irradiation in deuterated solvents. The efficiency of these photoisomerizations depended on the solvent and wavelength used. While (Z) dehydrozingerone and its corresponding (Z)-(Z) dimer proved to be highly unstable during purification, the O-methylated derivatives were successfully isolated, fully characterized by NMR spectroscopy, and further analyzed by UV-Vis spectroscopy and computational methods.

Jahanbani S., Mumivand H., Zahedi B., Argento S.

Basil (Ocimum basilicum L.) is a prominent medicinal and aromatic plant, widely recognized for its bioactive compounds and substantial economic value across the pharmaceutical, culinary, and industrial sectors. In light of increasing global demand and environmental challenges, this study explores novel approaches to enhance its sustainable production and improve its quality. Urea is the most common form of nitrogen (N) for foliar application due to its quick absorption, affordability, high solubility, as well as relatively low cost per N unit. Amino acids are an organic form of N and play a role in plant protein structure, stress tolerance, and the biosynthesis of secondary metabolites. This research aimed to evaluate the effects of urea (0, 1, and 2 g L−1) and an amino acid-based biostimulant (AAB) (0, 4, and 8 mg L−1), applied foliarly, on the growth, photosynthesis, pigments, antioxidant activity, and essential oil production of basil (Ocimum basilicum L.). The best results in terms of leaf number, area, and fresh and dry weight were observed with the combination of 2 g L−1 urea and 8 mg L−1 AAB. The growth enhancement due to this treatment may be attributed to stimulatory effects on photosynthesis and N content. Chlorophyll, carotenoids, anthocyanins, photosynthesis, stomatal conductance, total phenols, and total flavonoids increased with urea application up to 1 g L−1. Additionally, AAB application up to 8 mg L−1 increased total chlorophyll, carotenoid, total phenols, and total flavonoids, while photosynthesis and anthocyanin content increased with 4 mg L−1 AAB. Although urea did not significantly affect essential oil content and yield, AAB application increased both. Finally, the combination of 1 g L−1 urea and 8 mg L−1 AAB had the most effective impact on improving content and yield of essential oil, total phenol, flavonoid, anthocyanin, and antioxidant activity, with a relatively high percentage of estragole.