2-Substituted-4,7-dihydro-4-ethylpyrazolo[1,5-a]pyrimidin-7-ones alleviate LPS-induced inflammation by modulating cell metabolism via CD73 upon macrophage polarization.

Macrophage polarization towards the M1 phenotype under bacterial product-related exposure (LPS) requires a rapid change in gene expression patterns and cytokine production along with a metabolic rewiring. Metabolic pathways and redox reactions are such tightly connected, giving rise to an area of research referred to as immunometabolism. A role in this context has been paid to the master redox-sensitive regulator Nuclear factor erythroid 2-related factor 2 (Nrf2) and to the 5'-ectonucleotidase CD73, a marker related to macrophage metabolism rearrangement under pro-inflammatory conditions. In this light, a cell model of LPS-stimulated macrophages has been established and nine 4,7-dihydro-4-ethylpyrazolo[l,5-a]pyrimidin-7-ones with a potential anti-inflammatory effect have been administered. Our data highlight that two selected compounds (namely, 5 and 8) inhibit the LPS-induced Nrf2 nuclear translocation and ameliorate the activity rate of the antioxidant enzyme catalase. Additionally, the pyridine-containing compound (8) promotes the shift from the pro-inflammatory immunophenotype M1 to the pro-resolving M2 one, by downregulating CD80 and iNOS and by enhancing CD163 and TGFß1 expression. Most importantly, CD73 is modulated by these compounds as well as the lactate production. Our data demonstrate that pyrazolo[l,5-a]pyrimidine derivatives are effective as anti-inflammatory compounds. Furthermore, these pyrazolo[l,5-a]pyrimidines exert their action via CD73-related signaling and modulation of cell metabolism of activated macrophages.

Immunophenotyping of hemocytes from infected Galleria mellonella larvae as an innovative tool for immune profiling, infection studies and drug screening.

In recent years, there has been a considerable increasing interest in the use of the greater wax moth Galleria mellonella as an animal model. In vivo pharmacological tests, concerning the efficacy and the toxicity of novel compounds are typically performed in mammalian models. However, the use of the latter is costly, laborious and requires ethical approval. In this context, G. mellonella larvae can be considered a valid option due to their greater ease of use and the absence of ethical rules. Furthermore, it has been demonstrated that the immune system of these invertebrates has similarity with the one of mammals, thus guaranteeing the reliability of this in vivo model, mainly in the microbiological field. To better develop the full potential of this model, we present a novel approach to characterize the hemocyte population from G. mellonella larvae and to highlight the immuno modulation upon infection and treatments. Our approach is based on the detection in isolated hemocytes from G. mellonella hemolymph of cell membrane markers typically expressed by human immune cells upon inflammation and infection, for instance CD14, CD44, CD80, CD163 and CD200. This method highlights the analogies between G. mellonella larvae and humans. Furthermore, we provide an innovative tool to perform pre-clinical evaluations of the efficacy of antimicrobial compounds in vivo to further proceed with clinical trials and support drug discovery campaigns.

Modulation of NRF2: Biological Dualism in Cancer, Targets and Possible Therapeutic Applications.

Significance: The nuclear factor erythroid 2-related factor 2 (NRF2)-Kelch-like ECH-associated protein 1 (KEAP1) system is a master regulator of redox homeostasis and cell adaptation to a variety of exogenous and endogenous stressors. Accumulating evidence from the last decade indicates that the impairment of the redox balance leads to oxidative stress (OS), a common alteration occurring in many human acute and chronic inflammatory diseases, such as cancer, diabetes, neurodegeneration, and metabolic disorders, and aging. Recent Advances: Being located at the intersection of crucial signaling pathways, NRF2 can influence several cellular functions, which extend beyond the maintenance of the redox balance and include cellular metabolism, proteostasis, mitochondrial function and inflammation. For this reason, there is a growing interest in the pharmacologic manipulation of NRF2 for therapeutic purposes, which requires the accurate knowledge of the cell context and the specific time frame both of NRF2 activation and inhibition. This appears to be an important prerequisite and reflects the extreme complexity of the NRF2 signaling, characterized by an intrinsic dualism that mediates beneficial or detrimental effects even in the same biological process. Critical Issues: Of crucial importance will be to understand whether the NRF2 activity modulation might be exploited to exert beneficial outcomes in patients suffering from pathological conditions, in which the OS and the deregulation of inflammatory processes play a crucial role. Future Directions: In this review, we discuss the dual involvement of NRF2 in aging, neurodegeneration, metabolic diseases, long-COVID-19, and carcinogenesis and we present an overview of the most recent therapeutic modulators of NRF2, particularly emphasizing on those selected for clinical trials. Antioxid. Redox Signal. 40, 636-662.

A Multitarget Approach against Neuroinflammation: Alkyl Substituted Coumarins as Inhibitors of Enzymes Involved in Neurodegeneration.

Neurodegenerative disorders (NDs) include a large range of diseases characterized by neural dysfunction with a multifactorial etiology. The most common NDs are Alzheimer's disease and Parkinson's disease, in which cholinergic and dopaminergic systems are impaired, respectively. Despite different brain regions being affected, oxidative stress and inflammation were found to be common triggers in the pathogenesis and progression of both diseases. By taking advantage of a multi-target approach, in this work we explored alkyl substituted coumarins as neuroprotective agents, capable to reduce oxidative stress and inflammation by inhibiting enzymes involved in neurodegeneration, among which are Carbonic Anhydrases (CAs), Monoamine Oxidases (MAOs), and Cholinesterases (ChEs). The compounds were synthesized and profiled against the three targeted enzymes. The binding mode of the most promising compounds (7 and 9) within MAO-A and -B was analyzed through molecular modeling studies, providing and explanation for the different selectivities observed for the MAO isoforms. In vitro biological studies using LPS-stimulated rat astrocytes showed that some compounds were able to counteract the oxidative stress-induced neuroinflammation and hamper interleukin-6 secretion, confirming the success of this multitarget approach.

Natural products as a source of new anticancer chemotypes.

INTRODUCTION: Exploring the chemical diversity and molecular mechanisms of natural products continues to be an important research area for identifying novel promising therapeutic approaches for fighting cancer. This is a complex disease and poses important challenges, which require not only targeted interventions to improve chemotherapy efficacy and tolerability, but also adjuvant strategies to counteract chemoresistance development and relapses. AREAS COVERED: After a brief description of the recent literature on the anticancer potential of natural compounds, we searched for patents following the PRISMA guidelines, filtering the results published from 2019 onwards. In addition, some relevant publications from the overall scientific literature were also discussed. EXPERT OPINION: This review comprehensively covers and analyzes the most recent advances on the anticancer mechanism of licensed natural compounds and their chemical optimization. Patentability of natural compounds was discussed according to the recent legislation in the U.S.A. and Europe.

Quantum Molecular Resonance Inhibits NLRP3 Inflammasome/Nitrosative Stress and Promotes M1 to M2 Macrophage Polarization: Potential Therapeutic Effect in Osteoarthritis Model In Vitro.

This study aimed to investigate the anti-inflammatory effects of Quantum Molecular Resonance (QMR) technology in an in vitro model of osteoarthritis-related inflammation. The study used THP-1-derived macrophages stimulated with lipopolysaccharide and hyaluronic acid fragments to induce the expression of inflammatory cytokines and nitrosative stress. QMR treatment inhibited COX-2 and iNOS protein expression and activity and reduced NF-κB activity. Furthermore, QMR treatment led to a significant reduction in peroxynitrite levels, reactive nitrogen species that can form during inflammatory conditions, and restored tyrosine nitration values to those similar to sham-exposed control cells. We also investigated the effect of QMR treatment on inflammasome activation and macrophage polarization in THP-1-derived macrophages. Results showed that QMR treatment significantly decreased NLRP3 and activated caspase-1 protein expression levels and downregulated IL-18 and IL-1ß protein expression and secretion. Finally, our findings indicate that QMR treatment induces a switch in macrophage polarization from the M1 phenotype to the M2 phenotype.

Snail Slime Extracted by a Cruelty Free Method Preserves Viability and Controls Inflammation Occurrence: A Focus on Fibroblasts.

Snail slime (SS) is a viscous secretion obtained from different snail species. SS composition is variable according to factors such as the extraction method. Even if several papers have been published regarding this topic, the molecular mechanisms at the base of SS biological effects remain unexplored. Thus, the aim of this study is to evaluate the capability of SS, extracted with the cruelty-free Muller method, to promote viability and angiogenesis processes and, in parallel, to counteract inflammation occurrence on skin cell populations. SS was administered to keratinocytes, macrophages and fibroblasts, then cell viability, through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test, cytotoxicity by lactate dehydrogenase (LDH) assay, morphology by haematoxylin-eosin staining, gene and protein expression through real-time polymerase chain reaction (PCR) and Western blot, cell cycle phases by flow cytometry, and collagen secretion using an enzyme-linked immunosorbent assay (ELISA) test, were measured. Our results evidence SS capability to promote fibroblast viability and to trigger recovery mechanisms by activating the Erk protein. Moreover, an appreciable anti-inflammatory effect due to the significant reduction in cyclooxygenase-2 expression, and a positive modulation of new blood vessel formation demonstrated by increased Angiopoietin 1 gene expression and a higher matrix deposition (evidenced by the augmented amount of released collagen I) can be identified. This evidence led us to assume that the Muller method extracted-SS represents a valuable and promising natural product suitable for cosmetic and skin care formulations.

Phenylsulfonimide PPARα Antagonists Enhance Nrf2 Activation and Promote Oxidative Stress-Induced Apoptosis/Pyroptosis in MCF7 Breast Cancer Cells.

The NF-E2-related factor 2 transcription factor (Nrf2) orchestrates the basal and stress-inducible activation of a vast array of antioxidant genes. A high amount of reactive oxygen species (ROS) promotes carcinogenesis in cells with defective redox-sensitive signaling factors such as Nrf2. In breast cancer (BC), emerging evidence indicates that increased Nrf2 activity enhances cell metastatic potential. An interconnection between peroxisome proliferator-activated receptors (PPARs) and Nrf2 pathways in cancer has been shown. In this light, newly synthesized PPARα antagonists, namely IB42, IB44, and IB66, were tested in the BC cell line MCF7 in parallel with GW6471 as the reference compound. Our results show that the most promising compound of this phenylsulfonimide series (IB66) is able to decrease MCF7 proliferation by blocking cells at the G2/M checkpoint. The underlying mechanism has been investigated, disclosing a caspase 3/Akt-dependent apoptotic/pyroptotic pathway induced by the increased generation of oxidative stress. Moreover, the involvement of Nrf2 and COX2 in IB66-treated MCF7 cell response has been highlighted. The reported data lay the groundwork for the development of alternative targeted therapy involving the Nrf2/PPARα molecular axis, able to overcome BC cell chemoresistance and cause better clinical outcomes, promoting other forms of programmed cell death, such as pyroptosis.

The Inhibition of the Inducible Nitric Oxide Synthase Enhances the DPSC Mineralization under LPS-Induced Inflammation.

Nitric oxide (NO) is a key messenger in physiological and pathological processes in mammals. An excessive NO production is associated with pathological conditions underlying the inflammation response as a trigger. Among others, dental pulp inflammation results from the invasion of dentin by pathogenic bacteria. Vital functions of pulp mesenchymal stem cells (DPSCs, dental pulp stem cells), such as mineralization, might be affected by the inducible NOS (iNOS) upregulation. In this context, the iNOS selective inhibition can be considered an innovative therapeutic strategy to counteract inflammation and to promote the regeneration of the dentin-pulp complex. The present work aims at evaluating two acetamidines structurally related to the selective iNOS inhibitor 1400W, namely CM544 and FAB1020, in a model of LPS-stimulated primary DPSCs. Our data reveal that CM544 and even more FAB1020 are promising anti-inflammatory compounds, decreasing IL-6 secretion by enhancing CD73 expression-levels, a protein involved in innate immunity processes and thus confirming an immunomodulatory role of DPSCs. In parallel, cell mineralization potential is retained in the presence of compounds as well as VEGF secretion, and thus their angiogenetic potential. Data presented lay the ground for further investigation on the anti-inflammatory potential of acetamidines selectively targeting iNOS in a clinical context.

CD200 as a Potential New Player in Inflammation during Rotator Cuff Tendon Injury/Repair: An In Vitro Model.

Rotator cuff tendon (RCT) disease results from multifactorial mechanisms, in which inflammation plays a key role. Pro-inflammatory cytokines and tendon stem cell/progenitor cells (TSPCs) have been shown to participate in the inflammatory response. However, the underlying molecular mechanism is still not clear. In this study, flow cytometry analyses of different subpopulations of RCT-derived TSPCs demonstrate that after three days of administration, TNFα alone or in combination with IFNγ significantly decreases the percentage of CD146+CD49d+ and CD146+CD49f+ but not CD146+CD109+ TSPCs populations. In parallel, the same pro-inflammatory cytokines upregulate the expression of CD200 in the CD146+ TSPCs population. Additionally, the TNFα/IFNγ combination modulates the protein expression of STAT1, STAT3, and MMP9, but not fibromodulin. At the gene level, IRF1, CAAT (CAAT/EBPbeta), and DOK2 but not NF-κb, TGRF2 (TGFBR2), and RAS-GAP are modulated. In conclusion, although our study has several important limitations, the results highlight a new potential role of CD200 in regulating inflammation during tendon injuries. In addition, the genes analyzed here might be new potential players in the inflammatory response of TSPCs.

Natural and Synthetic Xanthone Derivatives Counteract Oxidative Stress via Nrf2 Modulation in Inflamed Human Macrophages.

Natural products have attracted attention due to their safety and potential effectiveness as anti-inflammatory drugs. Particularly, xanthones owning a unique 9H-xanthen-9-one scaffold, are endowed with a large diversity of medical applications, including antioxidant and anti-inflammatory activities, because their core accommodates a vast variety of substituents at different positions. Among others, α- and γ-mangostin are the major known xanthones purified from Garcinia mangostana with demonstrated anti-inflammatory and antioxidant effects by in vitro and in vivo modulation of the Nrf2 (nuclear factor erythroid-derived 2-like 2) pathway. However, the main mechanism of action of xanthones and their derivatives is still only partially disclosed, and further investigations are needed to improve their potential clinical outcomes. In this light, a library of xanthone derivatives was synthesized and biologically evaluated in vitro on human macrophages under pro-inflammatory conditions. Furthermore, structure-activity relationship (SAR) studies were performed by means of matched molecular pairs (MMPs). The data obtained revealed that the most promising compounds in terms of biocompatibility and counteraction of cytotoxicity are the ones that enhance the Nrf2 translocation, confirming a tight relationship between the xanthone scaffold and the Nrf2 activation as a sign of intracellular cell response towards oxidative stress and inflammation.

Characterization and Valorization of 'Sulmona Red Garlic' Peels and Small Bulbs.

'Sulmona red garlic' is an Italian variety characterized by a red tunica surrounding a white bulb. Red tunicae and non-commercial small bulbs are food wastes that must be studied for their added value. Hydroalcoholic extracts, obtained by separated inner and outer tunicae and peeled bulbs of small commercial 'Sulmona red garlic' bulbs, harvested at two different years, were first characterized with respect to their color, polyphenolic content, and antiradical activity. Then, an untargeted metabolic profile by means of electrospray ionization Fourier transform ion cyclotron resonance (ESI FT-ICR) mass spectrometry led to a comparative evaluation of the chemical diversity of six different samples. The study was completed by biological tests aiming to evaluate the associated health potential. Data on monocytes/macrophages showed good biocompatibility and a promising cytoprotective effect under oxidative stress conditions of all the extracts. At a molecular level, all the garlic extracts were able to downregulate the hydrogen peroxide-induced cyclooxygenase-2 and inducible nitric oxide synthase expression through the modulation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-ĸB) and peroxynitrite intracellular amounts, at different extents depending on the extract, the cell type, and the concentration. On the whole, data highlight an associated health potential of the extracts of this waste plant material both in terms of cytoprotection and of anti-inflammatory activity.

Hyaluronic Acid Alleviates Oxidative Stress and Apoptosis in Human Tenocytes via Caspase 3 and 7.

Rotator cuff tendinopathy (RCT) is the primary reason for shoulder surgery and its clinical management is still challenging. Hyaluronic acid (HA) has been shown to have anti-inflammatory effects in vitro and in vivo under RCT conditions, characterized by an exaggerated oxidative stress (OS). However, molecular mechanisms underlying HA-related effects are still partially disclosed. With these aims, a cell model of RCT was established by exposing primary human tenocytes to H2O2 for up to 72 h. Four different HAs by molecular weight were administered to measure nitric oxide (NO) and OS, apoptosis, and collagen 1 expression. In parallel, the well-known antioxidant ascorbic acid was administered for comparison. The present study highlights that HAs characterized by a low molecular weight are able to counteract the H2O2-induced OS by decreasing the percentage of apoptotic cells and reversing the activation of caspase 3 and 7. Likewise, NO intracellular levels are comparable to the ones of controls. In parallel, collagen 1 expression was ameliorated by HAs characterized by higher molecular weights compared to AA. These findings confirm that HA plays an antioxidant role comparable to AA depending on the molecular weight, and highlight the molecular mechanisms underlying the HA anti-apoptotic effects.

Modulatory Properties of Food and Nutraceutical Components Targeting NLRP3 Inflammasome Activation.

Inflammasomes are key intracellular multimeric proteins able to initiate the cellular inflammatory signaling pathway. NLRP3 inflammasome represents one of the main protein complexes involved in the development of inflammatory events, and its activity has been largely demonstrated to be connected with inflammatory or autoinflammatory disorders, including diabetes, gouty arthritis, liver fibrosis, Alzheimer's disease, respiratory syndromes, atherosclerosis, and cancer initiation. In recent years, it has been demonstrated how dietary intake and nutritional status represent important environmental elements that can modulate metabolic inflammation, since food matrices are an important source of several bioactive compounds. In this review, an updated status of knowledge regarding food bioactive compounds as NLRP3 inflammasome modulators is discussed. Several chemical classes, namely polyphenols, organosulfurs, terpenes, fatty acids, proteins, amino acids, saponins, sterols, polysaccharides, carotenoids, vitamins, and probiotics, have been shown to possess NLRP3 inflammasome-modulating activity through in vitro and in vivo assays, mainly demonstrating an anti-NLRP3 inflammasome activity. Plant foods are particularly rich in important bioactive compounds, each of them can have different effects on the pathway of inflammatory response, confirming the importance of the nutritional pattern (food model) as a whole rather than any single nutrient or functional compound.

Graphene-Oxide-Enriched Biomaterials: A Focus on Osteo and Chondroinductive Properties and Immunomodulation.

Due to its exceptional physical properties, such as high electronic conductivity, good thermal stability, excellent mechanical strength, and chemical versatility, graphene has sparked a lot of interest in the scientific community for various applications. It has therefore been employed as an antibacterial agent, in photothermal therapy (PTT) and biosensors, in gene delivery systems, and in tissue engineering for regenerative purposes. Since it was first discovered in 1947, different graphene derivatives have been synthetized from pristine graphene. The most adaptable derivate is graphene oxide (GO). Owing to different functional groups, the amphiphilic structure of GO can interact with cells and exogenous or endogenous growth/differentiation factors, allowing cell adhesion, growth, and differentiation. When GO is used as a coating for scaffolds and nanomaterials, it has been found to enhance bone, chondrogenic, cardiac, neuronal, and skin regeneration. This review focuses on the applications of graphene-based materials, in particular GO, as a coating for scaffolds in bone and chondrogenic tissue engineering and summarizes the most recent findings. Moreover, novel developments on the immunomodulatory properties of GO are reported.

Influence of HEMA on LPS- and LTA-stimulated IL-6 release from human dental pulp cells.

OBJECTIVE: Dental pulp cells interact with immunogenic components such as LPS (lipopolysaccharide) or LTA (lipoteichoic acid) released from microorganisms in carious lesions. In the present investigation, the formation of the pro-inflammatory cytokines TNFα and IL-6 in LPS- or LTA-stimulated cells from the dental pulp interface and pulp fibroblasts was analyzed in the presence of the resin monomer 2-hydroxyethyl methacrylate (HEMA) under varying cellular redox conditions. METHOD: Human pulp fibroblasts (HPC) or cells from the dental pulp interface expressing an odontoblast phenotype (hOD-1) were exposed to LTA, LPS or HEMA for 1 h or 24 h. Redox homeostasis was modified by the prooxidant BSO (L-buthionine sulfoximine) or the antioxidant NAC (N-acetyl cysteine). Formation of TNFα or IL-6 was analyzed by ELISA, and cell survival was determined by a crystal violet assay. Statistical analyses were performed using the Mann-Whitney-U-test. RESULTS: Secretion of TNFα was not detected in LPS- or LTA-stimulated HPC or hOD-1, and IL-6 was not found after a short exposure (1 h). After a 24 h exposure, LPS induced a 3-fold increase in IL-6 formation in HPC, while LTA stimulated IL-6 release about 20-fold. Likewise, LTA was more effective than LPS in hOD-1 stimulating IL-6 levels about 50-fold. HEMA inhibited the LPS- and LTA-induced IL-6 release, and this effect was enhanced by BSO but counteracted by NAC in both cell types. IL-6 release was independent of cell survival rates. CONCLUSIONS: The protective immune response in odontoblasts and pulp fibroblasts is impaired by monomers such as HEMA through the disturbance of the redox homeostasis.

Fisetin as a Senotherapeutic Agent: Biopharmaceutical Properties and Crosstalk between Cell Senescence and Neuroprotection.

Like other organs, brain functions diminish with age. Furthermore, for a variety of neurological disorders-including Alzheimer's disease-age is one of the higher-risk factors. Since in many Western countries the average age is increasing, determining approaches for decreasing the effects of aging on brain function is taking on a new urgency. Neuroinflammation and oxidative stress are two convoluted key factors in brain aging and chronic neurodegenerative diseases. The diverseness of factors, causing an age-related decrease in brain functions, requires identifying small molecules that have multiple biological activities that can affect all these factors. One great source of these small molecules is related to polyphenolic flavonoids. Recently, 3,3',4',7-tetrahydroxyflavone (fisetin) has been reported as a potent senotherapeutic capable of extending lifespan by reducing peroxidation levels and enhancing antioxidant cell responses. The neuroprotective effects of fisetin have been shown in several in vitro and in vivo models of neurological disorders due to its actions on multiple pathways associated with different neurological disorders. The present work aims to collect the most recent achievements related to the antioxidant and neuroprotective effects of fisetin. Moreover, in silico pharmacokinetics, pharmacodynamics, and toxicity of fisetin are also comprehensively described along with emerging novel drug delivery strategies for the amelioration of this flavonol bioavailability and chemical stability.

Negative Modulation of the Angiogenic Cascade Induced by Allosteric Kinesin Eg5 Inhibitors in a Gastric Adenocarcinoma In Vitro Model.

Eg5 is a kinesin essential in bipolar spindle formation, overexpressed in tumours, thus representing a new target in cancer therapy. We aimed at evaluating the anti-cancer activity of Eg5 thiadiazoline inhibitors 2 and 41 on gastric adenocarcinoma cells (AGS), focusing on the modulation of angiogenic signalling. Docking studies confirmed a similar interaction with Eg5 to that of the parent compound K858. Thiadiazolines were also tested in combination with Hesperidin (HSD). Cell cycle analysis reveals a reduction of G1 and S phase percentages when 41 is administered as well as HSD in combination with K858. Western blot reveals Eg5 inhibitors capability to reduce PI3K, p-AKT/Akt and p-Erk/Erk expressions; p-Akt/Akt ratio is even more decreased in HSD+2 sample than the p-Erk/Erk ratio in HSD+41 or K858. VEGF expression is reduced when HSD+2 and HSD+41 are administered with respect to compounds alone, after 72 h. ANGPT2 gene expression increases in cells treated with 41 and HSD+2 compared to K858. The wound-healing assay highlights a reduction in the cut in HSD+2 sample compared to 2 and HSD. Thus, Eg5 inhibitors appear to modulate angiogenic signalling by controlling VEGF activity even better if combined with HSD. Overall, Eg5 inhibitors can represent a promising starting point to develop innovative anti-cancer strategies.

A Novel Class of Dual-Acting DCH-CORMs Counteracts Oxidative Stress-Induced Inflammation in Human Primary Tenocytes.

Carbon monoxide (CO) can prevent cell and tissue damage by restoring redox homeostasis and counteracting inflammation. CO-releasing molecules (CORMs) can release a controlled amount of CO to cells and are emerging as a safer therapeutic alternative to delivery of CO in vivo. Sustained oxidative stress and inflammation can cause chronic pain and disability in tendon-related diseases, whose therapeutic management is still a challenge. In this light, we developed three small subsets of 1,5-diarylpyrrole and pyrazole dicobalt(0)hexacarbonyl (DCH)-CORMs to assess their potential use in musculoskeletal diseases. A myoglobin-based spectrophotometric assay showed that these CORMs act as slow and efficient CO-releasers. Five selected compounds were then tested on human primary-derived tenocytes before and after hydrogen peroxide stimulation to assess their efficacy in restoring cell redox homeostasis and counteracting inflammation in terms of PGE2 secretion. The obtained results showed an improvement in tendon homeostasis and a cytoprotective effect, reflecting their activity as CO-releasers, and a reduction of PGE2 secretion. As these compounds contain structural fragments of COX-2 selective inhibitors, we hypothesized that such a composite mechanism of action results from the combination of CO-release and COX-2 inhibition and that these compounds might have a potential role as dual-acting therapeutic agents in tendon-derived diseases.

Design, Synthesis and Biological Evaluation of Aromatase Inhibitors Based on Sulfonates and Sulfonamides of Resveratrol.

A library of sulfonate and sulfonamide derivatives of Resveratrol was synthesized and tested for its aromatase inhibitory potential. Interestingly, sulfonate derivatives were found to be more active than sulfonamide bioisosteres with IC50 values in the low micromolar range. The sulfonate analogues 1b-c and 1j exhibited good in vitro antiproliferative activity on the MCF7 cell line, evidenced by MTT and LDH release assays. Structure-activity relationships suggested that electronic and lipophilic properties could have a different role in promoting the biological response for sulfonates and sulfonamides, respectively. Docking studies disclosed the main interactions at a molecular level of detail behind the observed inhibition of the more active compounds whose chemical stability has been evaluated with nano-liquid chromatography. Finally, 1b-c and 1j were highlighted as sulfonates to be further developed as novel and original aromatase inhibitors.