Crosstalk between estrogen, dendritic cells, and SARS-CoV-2 infection.

The novel coronavirus disease 2019 (Covid-19) first appeared in Wuhan and has so far killed more than four million people worldwide. Men are more affected than women by Covid-19, but the cellular and molecular mechanisms behind these differences are largely unknown. One plausible explanation is that differences in sex hormones could partially account for this distinct prevalence in both sexes. Accordingly, several papers have reported a protective role of 17ß-estradiol during Covid-19, which might help explain why women appear less likely to die from Covid-19 than men. 17ß-estradiol is the predominant and most biologically active endogenous estrogen, which signals through estrogen receptor α, estrogen receptor ß, and G protein-coupled estrogen receptor 1. These receptors are expressed in mature cells from the innate and the adaptive immune system, particularly on dendritic cells (DCs), suggesting that estrogens could modulate their effector functions. DCs are the most specialized and proficient antigen-presenting cells, acting at the interface of innate and adaptive immunity with a powerful capacity to prime antigen-specific naive CD8+ T cells. DCs are richly abundant in the lung where they respond to viral infection. A relative increase of mature DCs in broncho-alveolar lavage fluids from Covid-19 patients has already been reported. Here we will describe how SARS-CoV-2 acts on DCs, the role of estrogen on DC immunobiology, summarise the impact of sex hormones on the immune response against Covid-19, and explore clinical trials regarding Covid-19.

Technology-enabled virtual ward for COVID management of the elderly and immunocompromised in Singapore: a descriptive cohort.

BACKGROUND: To address the hospital bed demand for Delta and Omicron surges in Singapore, the National University Health System (NUHS) developed a COVID Virtual Ward to relieve bed pressures on its three acute hospitals-National University Hospital, Ng Teng Fong General Hospital, Alexandra Hospital. To serve a multilingual population, the COVID Virtual Ward featuring protocolized teleconsultation of high-risk patients, use of a vital signs chatbot, supplemented by home visits where necessary. This study aims to evaluate the safety, outcomes and utilisation of the Virtual Ward as a scalable response to COVID-19 surges. METHODS: This is a retrospective cohort study of all patients admitted to the COVID Virtual Ward between 23 September to 9 November 2021. Patients were defined as "early discharge" if they were referred from inpatient COVID-19 wards and "admission avoidance" if they were referred directly from primary care or emergency services. Patient demographics, utilisation measures and clinical outcomes were extracted from the electronic health record system. The primary outcomes were escalation to hospital and mortality. Use of the vital signs chatbot was evaluated by examining compliance levels, need for automated reminders and alerts triggered. Patient experience was evaluated using data extracted from a quality improvement feedback form. RESULTS: 238 patients were admitted to the COVID Virtual Ward from 23 September to 9 November, of whom 42% were male, 67.6% of Chinese ethnicity. 43.7% were over the age of 70, 20.5% were immunocompromised, and 36.6% were not fully vaccinated. 17.2% of patients were escalated to hospital and 2.1% of patients died. Patients who were escalated to hospital were more likely to be immunocompromised or to have a higher ISARIC 4C-Mortality Score. There were no missed deteriorations. All patients received teleconsults (median of 5 teleconsults per patient, IQR 3-7). 21.4% of patients received home visits. 77.7% of patients engaged with the vital signs chatbot, with a compliance rate of 84%. All patients would recommend the programme to others in their situation. CONCLUSIONS: Virtual Wards are a scalable, safe and patient-centered strategy to care for high risk COVID-19 patients at home. TRIAL REGISTRATION: NA.

Transition metal (Ti, Cu, Zn, Pt) single-atom modified graphene/AS2 (A = Mo, W) van der Waals heterostructures for removing airborne pollutants.

Air pollution is a worldwide issue that affects human health and the environment. The scientific community tries to control it through different approaches, from experimental to theoretical assessments. Here, we perform DFT calculations to describe CO2, NO2, and SO2 detection on a single-atom (Ti, Cu, Zn, Pt) graphene supported on 2D molybdenum disulfide (MoS2) and tungsten disulfide (WS2). Transition metal single atoms on graphene improve the monolayer reactivity by generating an effective way to remove airborne pollutants. Results indicate that SO2 and NO2 chemically adsorb on all tested transition metals, whereas CO2 stands on top of the incorporated atoms through van der Waals interactions. Since strong Ti-O interactions appear, the Ti single-atom graphene/MoS2(WS2) systems efficiently remove CO2 from the environment. Compared to pristine graphene, our proposed heterostructures improve the SO2, NO2, and CO2 adsorption energies. The heterostructures' electronic properties change once the molecules interact with the transition metals, generating sensible and selective pollutant molecule detection and removal.

ER-mitochondria communication is involved in NLRP3 inflammasome activation under stress conditions in the innate immune system.

Endoplasmic reticulum (ER) stress and mitochondrial dysfunction, which are key events in the initiation and/or progression of several diseases, are correlated with alterations at ER-mitochondria contact sites, the so-called "Mitochondria-Associated Membranes" (MAMs). These intracellular structures are also implicated in NLRP3 inflammasome activation which is an important driver of sterile inflammation, however, the underlying molecular basis remains unclear. This work aimed to investigate the role of ER-mitochondria communication during ER stress-induced NLRP3 inflammasome activation in both peripheral and central innate immune systems, by using THP-1 human monocytes and BV2 microglia cells, respectively, as in vitro models. Markers of ER stress, mitochondrial dynamics and mass, as well as NLRP3 inflammasome activation were evaluated by Western Blot, IL-1ß secretion was measured by ELISA, and ER-mitochondria contacts were quantified by transmission electron microscopy. Mitochondrial Ca2+ uptake and polarization were analyzed with fluorescent probes, and measurement of aconitase and SOD2 activities monitored mitochondrial ROS accumulation. ER stress was demonstrated to activate the NLRP3 inflammasome in both peripheral and central immune cells. Studies in monocytes indicate that ER stress-induced NLRP3 inflammasome activation occurs by a Ca2+-dependent and ROS-independent mechanism, which is coupled with upregulation of MAMs-resident chaperones, closer ER-mitochondria contacts, as well as mitochondrial depolarization and impaired dynamics. Moreover, enhanced ER stress-induced NLRP3 inflammasome activation in the immune system was found associated with pathological conditions since it was observed in monocytes derived from bipolar disorder (BD) patients, supporting a pro-inflammatory status in BD. In conclusion, by demonstrating that ER-mitochondria communication plays a key role in the response of the innate immune cells to ER stress, this work contributes to elucidate the molecular mechanisms underlying NLRP3 inflammasome activation under stress conditions, and to disclose novel potential therapeutic targets for diseases associated with sterile inflammation.

Development of an in chemico high-throughput screening method for the identification of skin sensitization potential.

It is well established that chemical-peptide conjugation represents the molecular initiating event (MIE) in skin sensitization. This MIE has been successfully exploited in the development of in chemico peptide reactivity assays, with the Direct Peptide Reactivity Assay (DPRA) being validated as a screening tool for skin sensitization hazard as well as an OECD test guideline. This test relies on the use of a high-performance liquid chromatography/ultraviolet detection method to quantify chemical-peptide conjugation through measurement of the depletion of two synthetic peptides containing lysine or cysteine residues, which is labor-intensive and time-consuming. To improve assay throughput, sensitivity, and accuracy, we have developed a spectrophotometric assay for skin sensitization potential based on MIE measurement-the ProtReact assay. ProtReact is also a cheaper, faster, simpler, and more accessible alternative for the DPRA, giving comparable results. A set of 106 chemicals was tested with ProtReact and the peptide depletion values compared with those reported for the DPRA. The predictive capacity of both assays was evaluated with human reference data. ProtReact and DPRA assays show similar predictive capacities for hazard identification (75% and 74%, respectively), although ProtReact showed a higher specificity (86% versus 74%, respectively) and lower sensitivity (69% versus 73%). Overall, the results show that ProtReact assay described here represents an efficient, economic, and accurate assay for the prediction of skin sensitization potential of chemical haptens.

Development of colorimetric cellulose-based test-strip for the rapid detection of antibodies against SARS-CoV2 virus.

Given the pandemic situation, there is an urgent need for an accurate test to monitor antibodies anti-SARS-CoV-2, providing crucial epidemiological and clinical information to monitor the evolution of coronavirus disease in 2019 (COVID-19) and to stratify the immunized and asymptomatic population. Therefore, this paper describes a new cellulose-based test strip for rapid and cost-effective quantitative detection of antibodies to SARS-CoV2 virus by colorimetric transduction. For this purpose, Whatman paper was chemically modified with sodium metaperiodate to introduce aldehyde groups on its surface. Subsequently, the spike protein of the virus is covalently bound by forming an imine group. The chemical control of cellulose paper modification was evaluated by Fourier transform infrared spectroscopy, thermogravimetry and contact angle analysis. Colorimetric detection of the antibodies was performed by a conventional staining method using Ponceau S solution as the dye. Color analysis was performed after image acquisition with a smartphone using Image J software. The color intensity varied linearly with the logarithm of the anti-S concentration (from 10 ng/mL to 1 µg/mL) in 500-fold diluted serum samples when plotted against the green coordinate extracted from digital images. The test strip was selective in the presence of nucleocapsid antibodies, urea, glucose, and bovine serum albumin with less than 15% interference, and detection of antibodies in human serum was successfully performed. Overall, this is a simple and affordable design that can be readily used for mass population screening and does not require sophisticated equipment or qualified personnel. Supplementary Information: The online version contains supplementary material available at 10.1007/s10570-022-04808-y.

Forest Biomass as a Promising Source of Bioactive Essential Oil and Phenolic Compounds for Alzheimer's Disease Therapy.

Alzheimer's disease (AD) is the most common neurodegenerative disorder affecting elderly people worldwide. Currently, there are no effective treatments for AD able to prevent disease progression, highlighting the urgency of finding new therapeutic strategies to stop or delay this pathology. Several plants exhibit potential as source of safe and multi-target new therapeutic molecules for AD treatment. Meanwhile, Eucalyptus globulus extracts revealed important pharmacological activities, namely antioxidant and anti-inflammatory properties, which can contribute to the reported neuroprotective effects. This review summarizes the chemical composition of essential oil (EO) and phenolic extracts obtained from Eucalyptus globulus leaves, disclosing major compounds and their effects on AD-relevant pathological features, including deposition of amyloid-ß (Aß) in senile plaques and hyperphosphorylated tau in neurofibrillary tangles (NFTs), abnormalities in GABAergic, cholinergic and glutamatergic neurotransmission, inflammation, and oxidative stress. In general, 1,8-cineole is the major compound identified in EO, and ellagic acid, quercetin, and rutin were described as main compounds in phenolic extracts from Eucalyptus globulus leaves. EO and phenolic extracts, and especially their major compounds, were found to prevent several pathological cellular processes and to improve cognitive function in AD animal models. Therefore, Eucalyptus globulus leaves are a relevant source of biological active and safe molecules that could be used as raw material for nutraceuticals and plant-based medicinal products useful for AD prevention and treatment.

Therapies for Alzheimer's disease: a metabolic perspective.

Alzheimer's disease (AD) is one of the most common forms of dementia in the elderly. Currently, there are over 50 million cases of dementia worldwide and it is expected that it will reach 136 million by 2050. AD is described as a neurodegenerative disease that gradually compromises memory and learning capacity. Patients often exhibit brain glucose hypometabolism and are more susceptible to develop type 2 diabetes or insulin resistance in comparison with age-matched controls. This suggests that there is a link between both pathologies. Glucose metabolism and the tricarboxylic acid cycle are tightly related to mitochondrial performance and energy production. Impairment of both these pathways can evoke oxidative damage on mitochondria and key proteins linked to several hallmarks of AD. Glycation is also another type of post-translational modification often reported in AD, which might impair the function of proteins that participate in metabolic pathways thought to be involved in this illness. Despite needing further research, therapies based on insulin treatment, usage of anti-diabetes drugs or some form of dietary intervention, have shown to be promising therapeutic approaches for AD in its early stages of progression and will be unveiled in this paper.

Pharmacological combination of nivolumab with dendritic cell vaccines in cancer immunotherapy: An overview.

In the last decade, immunotherapy led to a paradigm shift in the treatment of numerous malignancies. Alongside with monoclonal antibodies blocking programmed cell death receptor-1 (PD-1)/PD-L1 and cytotoxic T- lymphocyte antigen 4 (CTLA-4) immune checkpoints, cell-based approaches such as CAR-T cells and dendritic cell (DC) vaccines have strongly contributed to pushing forward this thrilling field. While initial strategies were mainly focused on monotherapeutic regimens, it is now consensual that the combination of immunotherapies tackling multiple cancer hallmarks can result in superior clinical outcomes. Here, we review in depth the pharmacological combination of DC-based vaccines that boost tumour elimination by eliciting and expanding effector immune cells, with the PD-1 inhibitor Nivolumab that allows blocking key tumour immune escape mechanisms. This combination represents an important step in cancer therapy, with a significant enhancement in patient survival in several types of tumours, paving an important way in establishing combinatorial immunotherapeutic strategies as first-line treatments.

Systematic review on the definition and predictors of severe Clostridiodes difficile infection.

Clostridiodes difficile infection (CDI) is one of the most common hospital-acquired infections with high mortality rates. Optimal management of CDI depends on early recognition of severity. However, currently, there is no acceptable standard of prediction. We reviewed severe CDI predictors in published literature and its definition according to clinical guidelines. We systematically reviewed studies describing clinical predictors for severe CDI in medical databases (Cochrane, EMBASE, Global Health Library, and MEDLINE/PubMed). They were independently evaluated by two reviewers. Six hundred thirty-three titles and abstracts were screened, and 31 studies were included. We excluded studies that were restricted to a specific patient population. There were 16 articles that examined mortality in CDI, as compared with 15 articles investigating non-mortality outcomes of CDI. The commonest risk factors identified were comorbidities, white blood cell count, serum albumin level, age, serum creatinine level and intensive care unit admission. Generally, the studies had small patient populations, were retrospective in nature, and mostly from Western centers. The commonest severe CDI criteria in clinical guidelines were raised white blood cell count, followed by low serum albumin and raised serum creatinine levels. There was no commonly agreed upon definition of severe CDI severity in the literature. Current clinical guidelines' definitions for severe CDI are heterogeneous. Hence, there is a need for prospective multi-center studies using standardized protocol for biospecimen investigation collection and shared data on outcomes of patients in order to devise a universally accepted definition for severe CDI.

Antitumor Activity of Fucus vesiculosus-Derived Phlorotannins through Activation of Apoptotic Signals in Gastric and Colorectal Tumor Cell Lines.

Seaweeds are one of the largest producers of biomass in the marine environment and a source of multiple bioactive metabolites with valuable health benefits. Among these, phlorotannins have been widely recognized for their promising bioactive properties. The potential antitumor capacity of Fucus vesiculosus-derived phlorotannins remains, however, poorly explored, especially in gastrointestinal tract-related tumors. Therefore, this work aimed to evaluate the cytotoxic properties and possible mechanisms by which F. vesiculosus crude extract (CRD), phlorotannin-rich extract (EtOAc), and further phlorotannin-purified fractions (F1-F9) trigger cell death on different tumor cell lines of the gastrointestinal tract, using flow cytometry. The results indicate that F. vesiculosus samples exert specific cytotoxicity against tumor cell lines without affecting the viability of normal cells. Moreover, it was found that, among the nine different phlorotannin fractions tested, F5 was the most active against both Caco-2 colorectal and MKN-28 gastric cancer cells, inducing death via activation of both apoptosis and necrosis. The UHPLC-MS analysis of this fraction revealed, among others, the presence of a compound tentatively identified as eckstolonol and another as fucofurodiphlorethol, which could be mainly responsible for the promising cytotoxic effects observed in this sample. Overall, the results herein reported contribute to a better understanding of the mechanisms behind the antitumor properties of F. vesiculosus phlorotannin-rich extracts.

In vitro evaluation of potential benefits of a silica-rich thermal water (Monfortinho Thermal Water) in hyperkeratotic skin conditions.

Thermal therapy has gained popularity over the years, and Portugal is one of the richest European countries in mineral therapeutic waters. The interest in the use of these natural mineral waters (NMW) for dermatologic purposes is continuously growing but there is a lack of scientific studies supporting its health benefits. The study aims to investigate the effect of a silica-rich NMW in skin cell homeostasis using two representative cell lines of the epidermis and dermis, keratinocytes and fibroblasts, respectively, in addition to a macrophage cell line. Mouse skin fibroblasts, macrophages and human keratinocytes were exposed to culture medium prepared with NMW. Cell metabolism (MTT or resazurin assays) and cell proliferation (trypan blue exclusion dye assay) were investigated. Migration (scratch-wound assay) and senescence (ß-galactosidase activity assay) of fibroblasts were also studied. Exposure to NMW compromised the cell metabolic state of all the cell lines tested. This impairment was more pronounced in skin keratinocytes (60% reduction) relatively to skin fibroblasts (45% reduction) or macrophages (25% reduction). Proliferation of macrophages was reduced threefold upon exposure to thermal water, compared to controls. No differences were observed in migration between fibroblasts exposed to NMW and controls, while a potentiation of senescence of these cells was observed. Our results shed light in the bioactive effects of a silica-rich NMW supporting its therapeutic use. A reduction in both cell metabolism and proliferation of keratinocytes and macrophages supports the empirical clinical benefits of this NMW in hyperkeratotic conditions, such as psoriasis and atopic dermatitis.

Calcium Modulation, Anti-Oxidant and Anti-Inflammatory Effect of Skin Allergens Targeting the Nrf2 Signaling Pathway in Alzheimer's Disease Cellular Models.

Experimental evidence highlights nuclear factor (erythroid-derived 2)-like 2 (Nrf2) as a molecular target in Alzheimer's disease (AD). The well-known effect of electrophilic cysteine-reactive skin allergens on Nrf2-activation led to the hypothesis that these compounds could have a therapeutic role in AD. This was further supported by the neuroprotective activity of the skin allergen dimethyl fumarate (DMF), demonstrated in in vivo models of neurodegenerative diseases. We evaluated the effect of the cysteine-reactive allergens 1,4-phenylenediamine (PPD) and methyl heptine carbonate (MHC) on (1) neuronal redox imbalance and calcium dyshomeostasis using N2a wild-type (N2a-wt) and human APP-overexpressing neuronal cells (wild-type, N2a-APPwt) and (2) on neuroinflammation, using microglia BV-2 cells exposed to LPS (lipopolysaccharide). Phthalic anhydride (PA, mainly lysine-reactive), was used as a negative control. DMF, PPD and MHC increased Hmox1 gene and HMOX1 protein levels in N2a-APPwt cells suggesting Nrf2-dependent antioxidant activity. MHC, but also PA, rescued N2a-APPwt mitochondrial membrane potential and calcium levels in a Nrf2-independent pathway. All the chemicals showed anti-inflammatory activity by decreasing iNOS protein in microglia. This work highlights the potential neuroprotective and anti-inflammatory role of the selected skin allergens in in vitro models of AD, and supports further studies envisaging the validation of the results using in vivo AD models.

Chemical signature and antimicrobial activity of Central Portuguese Natural Mineral Waters against selected skin pathogens.

The common therapeutic indications of Portuguese Natural Mineral Waters (NMWs) are primarily for respiratory, rheumatic and musculoskeletal systems. However, these NMWs have been increasingly sought for dermatologic purposes. Opposing to what is observed in the major European Thermal Centres, there are few scientific evidences supporting the use of Portuguese NMWs for clinical applications. The aim of this study was to characterize the antimicrobial profile of individual NMWs from the central region of Portugal and correlate the results with their physicochemical characterization. An extensive multivariate analysis (principal component analysis) was also performed to further investigate this possible correlation. Six collection strains representing skin microbiota, namely Staphylococcus aureus, Escherichia coli, Corynebacterium amycolatum, Candida albicans, Staphylococcus epidermidis and Cutibacterium acnes, were analysed, and their antimicrobial profile was determined using Clinical and Laboratory Standards Institute M07-A10, M45-A2, M11-A6 and M27-A3 microdilution methods. Different NMWs presented different antimicrobial profiles against the strains used; the physicochemical composition of NMWs seemed to be correlated with the different susceptibility profiles. Cutibacterium acnes showed a particularly high susceptibility to all NMWs belonging sulphurous/bicarbonated/sodic ionic profile, exhibiting microbial reductions up to 65%. However, due to the complex physicochemical composition of each water an overall conclusion regarding the effect of a specific ion on the growth of different microorganisms is yet to be known.

Ischaemia alters the effects of cardiomyocyte-derived extracellular vesicles on macrophage activation.

Myocardial ischaemia is associated with an exacerbated inflammatory response, as well as with a deregulation of intercellular communication systems. Macrophages have been implicated in the maintenance of heart homeostasis and in the progression and resolution of the ischaemic injury. Nevertheless, the mechanisms underlying the crosstalk between cardiomyocytes and macrophages remain largely underexplored. Extracellular vesicles (EVs) have emerged as key players of cell-cell communication in cardiac health and disease. Hence, the main objective of this study was to characterize the impact of cardiomyocyte-derived EVs upon macrophage activation. Results obtained demonstrate that EVs released by H9c2 cells induced a pro-inflammatory profile in macrophages, via p38MAPK activation and increased expression of iNOS, IL-1ß and IL-6, being these effects less pronounced with ischaemic EVs. EVs derived from neonatal cardiomyocytes, maintained either in control or ischaemia, induced a similar pattern of p38MAPK activation, expression of iNOS, IL-1ß, IL-6, IL-10 and TNFα. Importantly, adhesion of macrophages to fibronectin was enhanced by EVs released by cardiomyocytes under ischaemia, whereas phagocytic capacity and adhesion to cardiomyocytes were higher in macrophages incubated with control EVs. Additionally, serum-circulating EVs isolated from human controls or acute myocardial infarction patients induce macrophage activation. According to our model, in basal conditions, cardiomyocyte-derived EVs maintain a macrophage profile that ensure heart homeostasis, whereas during ischaemia, this crosstalk is affected, likely impacting healing and post-infarction remodelling.

Urolithins impair cell proliferation, arrest the cell cycle and induce apoptosis in UMUC3 bladder cancer cells.

Ellagitannins have been gaining attention as potential anticancer molecules. However, the low bioavailability of ellagitannins and their extensive metabolization in the gastrointestinal tract into ellagic acid and urolithins suggest that the health benefits of consuming ellagitannins rely on the direct effects of their metabolites. Recently, chemopreventive and chemotherapeutic activities were ascribed to urolithins. Nonetheless, there is still a need to screen and evaluate the selectivity of these molecules and to elucidate their cellular mechanisms of action. Therefore, this work focused on the antiproliferative effects of urolithins A, B and C and ellagic acid on different human tumor cell lines. The evaluation of cell viability and the determination of the half-maximal inhibitory concentrations indicated that the sensitivity to the studied urolithins varied markedly between the different cell lines, with the bladder cancer cells (UMUC3) being the most susceptible. In UMUC3 cells, urolithin A was the most active molecule, promoting cell cycle arrest at the G2/M checkpoint, increasing apoptotic cell death and inhibiting PI3K/Akt and MAPK signaling. Overall, the present study emphasizes the chemopreventive/chemotherapeutic potential of urolithins, highlighting the stronger effects of urolithin A and its potential to target transitional bladder cancer cells.

Contact dermatitis: in pursuit of sensitizer's molecular targets through proteomics.

Protein haptenation, i.e., the modification of proteins by small reactive chemicals, is the key step in the sensitization phase of allergic contact dermatitis (ACD). Despite the research effort in past decades, the identification of immunogenic hapten-protein complexes that trigger a relevant pathogenic immune response in ACD, as well as the haptenation reaction molecular site, and the elements of a potentially conditioning environment during each of these stages, remain poorly understood. These questions led us to employ a proteomics-based approach to identify modified proteins in the dendritic-like cell line THP-1 sensitized with fluorescein isothiocyanate (FITC), through a combination of 2D-gel electrophoresis, nano-LC and mass spectrometry. A specific set of 39 targeted proteins was identified and comprised proteins from various cellular locations and biological functions. One of FITC targets was identified as MLK, a member of the mixed-lineage kinase family known to act as a mitogen-activated protein kinase kinase kinase and to control the activity of specific mitogen-activated protein kinase pathways, namely p38 and JNK pathways. Haptenated in the vicinity of its active site, our results point to MLK being a relevant target due to a consistent non-activation at early time points of these pathways upon FITC sensitization in THP-1 cells. Moreover, FITC pre-treatment significantly decrease phospho-p38 and phospho-JNK levels induced upon exposure to a classical activator such as lipopolysaccharide or to the sensitizer 2,4-dinitrofluorobenzene. Overall, our data point to specific amino acid residues haptenation within critical proteins as the key step in the subsequent signaling pathways modulation responsible for DC activation and maturation events.

Valorization of Lipids from Gracilaria sp. through Lipidomics and Decoding of Antiproliferative and Anti-Inflammatory Activity.

The lipidome of the red seaweed Gracilaria sp., cultivated on land-based integrated multitrophic aquaculture (IMTA) system, was assessed for the first time using hydrophilic interaction liquid chromatography-mass spectrometry and tandem mass spectrometry (HILIC-MS and MS/MS). One hundred and forty-seven molecular species were identified in the lipidome of the Gracilaria genus and distributed between the glycolipids classes monogalactosyl diacylglyceride (MGDG), digalactosyl diacylglyceride (DGDG), sulfoquinovosyl monoacylglyceride (SQMG), sulfoquinovosyl diacylglyceride (SQDG), the phospholipids phosphatidylcholine (PC), lyso-PC, phosphatidylglycerol (PG), lyso-PG, phosphatidylinositol (PI), phosphatidylethanolamine (PE), phosphatic acid (PA), inositolphosphoceramide (IPC), and betaine lipids monoacylglyceryl- and diacylglyceryl-N,N,N-trimethyl homoserine (MGTS and DGTS). Antiproliferative and anti-inflammatory effects promoted by lipid extract of Gracilaria sp. were evaluated by monitoring cell viability in human cancer lines and by using murine macrophages, respectively. The lipid extract decreased cell viability of human T-47D breast cancer cells and of 5637 human bladder cancer cells (estimated half-maximal inhibitory concentration (IC50) of 12.2 µg/mL and 12.9 µg/mL, respectively) and inhibited the production of nitric oxide (NO) evoked by the Toll-like receptor 4 agonist lipopolysaccharide (LPS) on the macrophage cell line RAW 264.7 (35% inhibition at a concentration of 100 µg/mL). These findings contribute to increase the ranking in the value-chain of Gracilaria sp. biomass cultivated under controlled conditions on IMTA systems.

Chemical Composition of Laurencia obtusa Extract and Isolation of a New C15-Acetogenin.

A new C15-acetogenin, sagonenyne (20), exhibiting an unusual single tetrahydropyran ring was isolated from an ethyl acetate extract of Laurencia obtusa collected on the Corsican coastline. Its structure was established by detailed NMR spectroscopic analysis, mass spectrometry, and comparison with literature data. Twenty-three known compounds were identified in the same extract by means of column chromatography steps, using a 13C-NMR computer aided method developed in our laboratory. In addition to sesquiterpenes, which represent the main chemical class of this extract, diterpenes, sterols, and C15-acetogenins were identified. The crude extract was submitted to a cytotoxicity assay and was particularly active against THP-1 cells, a human leukemia monocytic cell line.

Phospholipidomic Profile Variation on THP-1 Cells Exposed to Skin or Respiratory Sensitizers and Respiratory Irritant.

Occupational exposure to low molecular weight reactive chemicals often leads to development of allergic reactions such as allergic contact dermatitis and respiratory allergies. Further insights into the interaction of these chemicals with physiopathological relevant cellular models might provide the foundations for novel non-animal approaches to safety assessment. In this work we used the human THP-1 cell line to determine phospholipidome changes induced by the skin sensitizer 1-fluoro-2,4-dinitrobenzene (DNFB), the respiratory allergen hexamethylene diisocyanate (HDI), and the irritant methyl salicylate (MESA). We detected that these chemicals differently induce lipid peroxidation and modulate THP-1 IL-1ß, IL-12B, IL-8, CD86, and HMOX1 transcription. Decreased phosphatidylethanolamine content was detected in cells exposed to MESA, while profound alterations in the relative abundance of cardiolipin species were observed in cells exposed to DNFB. All chemicals tested induced a decrease in the relative abundance of plasmanyl phosphatidylcholine species PC (O-16:0e/18:1) and phosphatidylinositol species PI (34:1), while increasing PI (38:4). An increased abundance of oleic acid was observed in the phospholipids of cells exposed to DNFB while a decreased abundance of palmitic acid was detected in cells treated with MESA or DNFB. We conclude that both specific and common alterations at phospholipidome levels are triggered by the different chemicals, while not allowing a complete distinction between them using a Canonical Analysis of Principal Coordinates (CAP). The common effects observed at phospholipids level with all the chemicals tested might be related to unspecific cell cytotoxic mechanisms that nevertheless may contribute to the elicitation of specific immune responses. J. Cell. Physiol. 231: 2639-2651, 2016. © 2016 Wiley Periodicals, Inc.