The TRPM2 ion channel regulates metabolic and thermogenic adaptations in adipose tissue of cold-exposed mice

Introduction

During thermogenesis, adipose tissue (AT) becomes more active and enhances oxidative metabolism. The promotion of this process in white AT (WAT) is called "browning" and, together with the brown AT (BAT) activation, is considered as a promising approach to counteract obesity and metabolic diseases. Transient receptor potential cation channel, subfamily M, member 2 (TRPM2), is an ion channel that allows extracellular Ca2+ influx into the cytosol, and is gated by adenosine diphosphate ribose (ADPR), produced from NAD+ degradation. The aim of this study was to investigate the relevance of TRPM2 in the regulation of energy metabolism in BAT, WAT, and liver during thermogenesis.

Methods

Wild type (WT) and Trpm2-/- mice were exposed to 6°C and BAT, WAT and liver were collected to evaluate mRNA, protein levels and ADPR content. Furthermore, O2 consumption, CO2 production and energy expenditure were measured in these mice upon thermogenic stimulation. Finally, the effect of the pharmacological inhibition of TRPM2 was assessed in primary adipocytes, evaluating the response upon stimulation with the β-adrenergic receptor agonist CL316,243.

Results

Trpm2-/- mice displayed lower expression of browning markers in AT and lower energy expenditure in response to thermogenic stimulus, compared to WT animals. Trpm2 gene overexpression was observed in WAT, BAT and liver upon cold exposure. In addition, ADPR levels and mono/poly-ADPR hydrolases expression were higher in mice exposed to cold, compared to control mice, likely mediating ADPR generation.

Discussion

Our data indicate TRPM2 as a fundamental player in BAT activation and WAT browning. TRPM2 agonists may represent new pharmacological strategies to fight obesity.

Early investigation of a novel SI306 theranostic prodrug for glioblastoma treatment

Glioblastoma multiforme (GBM) is one of the most aggressive malignancies with a high recurrence rate and poor prognosis. Theranostic, combining therapeutic and diagnostic approaches, arises as a successful strategy to improve patient outcomes through personalized medicine. Src is a non-receptor tyrosine kinase (nRTK) whose involvement in GBM has been extensively demonstrated. Our previous research highlighted the effectiveness of the pyrazolo[3,4-d]pyrimidine SI306 and its more soluble prodrug CMP1 as Src inhibitors both in in vitro and in vivo GBM models. In this scenario, we decided to develop a theranostic prodrug of SI306, ProSI-DOTA(68 Ga) 1, which was designed to target GBM cells after hydrolysis and follow-up on the disease's progression and improve the therapy's outcome. First, the corresponding nonradioactive prodrug 2 was tested to evaluate its ADME profile and biological activity. It showed good metabolic stability, no inhibition of CYP3A4, suboptimal aqueous solubility, and slight gastrointestinal and blood-brain barrier passive permeability. Compound 2 exhibited a drastic reduction of cell vitality after 72 h on two different GBM cell lines (GL261 and U87MG). Then, 2 was subjected to complexation with the radionuclide Gallium-68 to give ProSI-DOTA(68 Ga) 1. The cellular uptake of 1 was evaluated on GBM cells, highlighting a slight but significant time-dependent uptake. The data obtained from our preliminary studies reflect the physiochemical properties of 1. The use of an alternative route of administration, such as the intranasal route, could overcome the physiochemical limitations and enhance the pharmacokinetic properties of 1, paving the way for its future development.

Polyphenol-enriched extracts of Sarcopoterium spinosum fruits for counteracting lipid accumulation and oxidative stress in an in vitro model of hepatic steatosis

Sarcopoterium spinosum (L.) Spach is a Rosaceae shrub employed in the folk medicine in the Eastern Mediterranean basin. The previous few studies have focused on the S. spinosum roots, while the fruits have been poorly investigated. The present study aims to assess the biological properties of S. spinosum fruits collected in Lebanon and subjected to ethanolic, water or boiling water extraction. The extracts were compared for the phenol and flavonoid contents, and for the in vitro radical scavenging ability. The ethanolic extract (SEE) was selected and characterized by high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS) showing a phenolome rich in tannins (ellagitannins), flavonoids (quercetin derivatives), and triterpenes. The biological activity of SEE was tested on a cellular model of moderate steatosis consisting of lipid-loaded hepatic cells treated with increasing concentrations of SEE (1-25 μg/mL), or with corilagin or quercetin as comparison. In steatotic hepatocytes the SEE was able (i) to ameliorate the hepatosteatosis; (ii) to counteract the excess ROS and lipid peroxidation; (iii) to restore the impaired catalase activity. The results indicate that the ethanolic extract from S. spinosum fruits is endowed with relevant antisteatotic and antioxidant activities and might find application as nutraceutical product.

SIRT6 pharmacological inhibition delays skin cancer progression in the squamous cell carcinoma

Sirtuin 6 (SIRT6) has a critical role in cutaneous Squamous Cell Carcinoma (cSCC): SIRT6 silencing in skin SCC cells has pro-differentiating effects and SIRT6 deletion abrogated DMBA-TPA-induced skin tumorigenesis in mice. On the other hand, SIRT6 acts as tumor suppressor in SCC by enhancing glycolysis in tumor propagating cells. Herein, pharmacological modulation of SIRT6 deacetylase activity was investigated in cSCC, with S6 (inhibitor) or MDL-800 (activator). In cSCC cells, S6 recreated the pro-differentiating effects of SIRT6 silencing, as the levels of Keratin 1, Keratin 10 and Loricrin were upregulated compared to controls. Next, the effects of SIRT6 pharmacological modulation were evaluated in a DMBA-TPA-induced skin cancer mouse model. Mice treated with the inhibitor S6 in a preventive approach, i.e. at the beginning of the promotion stage, presented reduced number and size of papillomas, compared to the controls. The epidermal hyperproliferation marker Keratin 6 and the cSCC marker Keratin 8 were less abundant when SIRT6 was inhibited. In S6-treated lesions, the Epithelial-Mesenchymal Transition (EMT) markers Zeb1 and Vimentin were less expressed compared to untreated lesions. In a therapeutic approach, i.e. treatment starting after papilloma appearance, the S6 group presented reduced papillomas (number and size), whereas MDL-800-treated mice displayed an opposite trend. In S6-treated lesions, Keratin 6 and Keratin 8 were less expressed, EMT was less advanced, with a higher E-cadherin/Vimentin ratio, indicating a delayed carcinogenesis when SIRT6 was inhibited. Our results confirm that SIRT6 plays a role in skin carcinogenesis and suggest SIRT6 pharmacological inhibition as a promising strategy in cSCC.

Virtual Screening Combined with Enzymatic Assays to Guide the Discovery of Novel SIRT2 Inhibitors

Sirtuin isoform 2 (SIRT2) is one of the seven sirtuin isoforms present in humans, being classified as class III histone deacetylases (HDACs). Based on the high sequence similarity among SIRTs, the identification of isoform selective modulators represents a challenging task, especially for the high conservation observed in the catalytic site. Efforts in rationalizing selectivity based on key residues belonging to the SIRT2 enzyme were accompanied in 2015 by the publication of the first X-ray crystallographic structure of the potent and selective SIRT2 inhibitor SirReal2. The subsequent studies led to different experimental data regarding this protein in complex with further different chemo-types as SIRT2 inhibitors. Herein, we reported preliminary Structure-Based Virtual Screening (SBVS) studies using a commercially available library of compounds to identify novel scaffolds for the design of new SIRT2 inhibitors. Biochemical assays involving five selected compounds allowed us to highlight the most effective chemical features supporting the observed SIRT2 inhibitory ability. This information guided the following in silico evaluation and in vitro testing of further compounds from in-house libraries of pyrazolo-pyrimidine derivatives towards novel SIRT2 inhibitors (1-5). The final results indicated the effectiveness of this scaffold for the design of promising and selective SIRT2 inhibitors, featuring the highest inhibition among the tested compounds, and validating the applied strategy.

Photoprotective and Anti-Aging Properties of the Apical Frond Extracts from the Mediterranean Seaweed Ericaria amentacea

There is a growing interest in using brown algal extracts thanks to the bioactive substances they produce for adaptation to the marine benthic environment. We evaluated the anti-aging and photoprotective properties of two types of extracts (50%-ethanol and DMSO) obtained from different portions, i.e., apices and thalli, of the brown seaweed, Ericaria amentacea. The apices of this alga, which grow and develop reproductive structures during summer when solar radiation is at its peak, were postulated to be rich in antioxidant compounds. We determined the chemical composition and pharmacological effects of their extracts and compared them to the thallus-derived extracts. All the extracts contained polyphenols, flavonoids and antioxidants and showed significant biological activities. The hydroalcoholic apices extracts demonstrated the highest pharmacological potential, likely due to the higher content of meroditerpene molecular species. They blocked toxicity in UV-exposed HaCaT keratinocytes and L929 fibroblasts and abated the oxidative stress and the production of pro-inflammatory cytokines, typically released after sunburns. Furthermore, the extracts showed anti-tyrosinase and anti-hydrolytic skin enzyme activity, counteracting the collagenase and hyaluronidase degrading activities and possibly slowing down the formation of uneven pigmentation and wrinkles in aging skin. In conclusion, the E. amentacea apices derivatives constitute ideal components for counteracting sunburn symptoms and for cosmetic anti-aging lotions.

Pentoxifylline and tocopherol for prevention of osteoradionecrosis in patients who underwent oral surgery: A clinical audit

PURPOSE

Osteoradionecrosis (ORN) of the jaw is a severe and debilitating complication of the head and neck radiotherapy which frequently occurrs after oral surgery. This clinical audit aims aevaluate the effectiveness of combined use of pentoxifylline and tocopherol (PENTO) in prevention ORN onset in patient who underwent oral surgery after head and neck radiotherapy (RT).

MATERIAL METHOD

In this clinical audit Pentoxifylline 400 mg, twice a day, and Tocopherol 800 IU once a day (PENTO protocol) have been prescribed. Patients started the protocol 1 week before the surgical procedure and continued for 8 weeks after.

RESULTS

Twenty-nine patients were included. They received 75 surgical interventions under PENTO protocol: 71 surgical procedures of dental extraction (single or multiple dental extractions in each session) and four implant placements. A total of 152 dental extractions were carried out: 64 surgical extractions which required the raising of mucoperiosteal flap, and 88 simple extractions. Four out of 29 patients developed ORN after surgical procedures: four cases of ORN occurred after dental extractions (5.6%) and one case of ORN after implant placement (25%).

CONCLUSION

PENTO is a useful ORN preventive protocol, low-cost and clinically feasible, safe and well tolerated by patients. Further studies should focus on better defining the effectiveness PENTO, independently from the antibiotic therapy.

Combining voltammetric and mass spectrometric data to evaluate iron organic speciation in subsurface coastal seawater samples of the Ross sea (Antarctica)

Iron (Fe) is the most important trace element in the ocean, as it is required by phytoplankton for photosynthesis and nitrate assimilation. Iron speciation is important to better understand the biogeochemical cycle and availability of this micronutrient, in particular in the Southern Ocean. Dissolved Fe (dFe) concentration and speciation were determined in 24 coastal subsurface seawater samples collected in the western Ross sea (Antarctica) during the austral summer 2017 as part of the CELEBeR (CDW Effects on glacial mElting and on Bulk of Fe in the Western Ross sea) project. ICP-DRC-MS was used for dFe determination, whereas CLE-AdSV was used to obtain the concentration of complexed and free dFe, of the ligands, and the values of the stability constants of the complexes. Dissolved Fe values ranged from 0.4 to 2.5 nM and conditional stability constant (logK'Fe'L) from 13.0 to 15.0, highlighting the presence of Fe-binding organic complexes of different stabilities. Principal component analysis (PCA) allowed us to point out that Terra Nova Bay and the neighboring area of Aviator and Mariner Glaciers were different in terms of chemical, physical, and biological parameters. A qualitative investigation on the nature of the organic ligands was carried out by HPLC-ESI-MS/MS. Results showed that siderophores represented a heterogeneous class of organic ligands pool.

New Class of Benzodiazepinone Derivatives as Pro-Death Agents Targeting BIR Domains in Cancer Cells

Inhibitor of Apoptosis Proteins (IAPs) are validated targets for cancer therapy, and the deregulation of their activities within the NF-κB pathway correlates with chemoresistance events, even after treatment with IAPs-antagonists in the clinic (Smac-mimetics). The molecule FC2 was identified as a NF-κB pathway modulator in MDA-MB-231 adenocarcinoma cancer cells after virtual screening of the Chembridge library against the Baculoviral IAP Repeat 1 (BIR1) domain of cIAP2 and XIAP. An improved cytotoxic effect is observed when FC2 is combined with Smac-mimetics or with the cytokine Tumor Necrosis Factor (TNF). Here, we propose a library of 22 derivatives of FC2, whose scaffold was rationally modified starting from the position identified as R₁. The cytotoxic effect of FC2 derivatives was evaluated in MDA-MB-231 and binding to the cIAP2- and XIAP-BIR1 domains was assessed in fluorescence-based techniques and virtual docking. Among 22 derivatives, 4m and 4p display improved efficacy/potency in MDA-MB-231 cells and low micromolar binding affinity vs the target proteins. Two additional candidates (4b and 4u) display promising cytotoxic effects in combination with TNF, suggesting the connection between this class of molecules and the NF-κB pathway. These results provide the rationale for further FC2 modifications and the design of novel IAP-targeting candidates supporting known therapies.

First Evidence of Anti-Steatotic Action of Macrotympanain A1, an Amphibian Skin Peptide from Odorrana macrotympana

Many different amphibian skin peptides have been characterized and proven to exert various biological actions, such as wound-healing, immunomodulatory, anti-oxidant, anti-inflammatory and anti-diabetic effects. In this work, the possible anti-steatotic effect of macrotympanain A1 (MA1) (FLPGLECVW), a skin peptide isolated from the Chinese odorous frog Odorrana macrotympana, was investigated. We used a well-established in vitro model of hepatic steatosis, consisting of lipid-loaded rat hepatoma FaO cells. In this model, a 24 h treatment with 10 µg/mL MA1 exerted a significant anti-steatotic action, being able to reduce intracellular triglyceride content. Accordingly, the number and diameter of cytosolic lipid droplets (LDs) were reduced by peptide treatment. The expression of key genes of hepatic lipid metabolism, such as PPARs and PLINs, was measured by real-time qPCR. MA1 counteracted the fatty acid-induced upregulation of PPARγ expression and increased PLIN3 expression, suggesting a role in promoting lipophagy. The present data demonstrate for the first time a direct anti-steatotic effect of a peptide from amphibian skin secretion and pave the way to further studies on the use of amphibian peptides for beneficial actions against metabolic diseases.

Electrophysiological study of the effects of side products of RuBi-GABA uncaging on GABAA receptors in cerebellar granule cells

The study of the GABAA receptor itself and its pharmacology is of paramount importance for shedding light on the role of this receptor in the central nervous system. Caged compounds have emerged as powerful tools to support research in this field, as they allow to control, in space and time, the release of neurotransmitters enabling, for example, to map receptors’ distribution and dynamics. Here we focus on γ-aminobutyric acid (GABA)-caged compounds, particularly on a commercial complex called RuBi-GABA, which has high efficiency of uncaging upon irradiation at visible wavelengths. We characterized, by electrophysiological measurements, the effects of RuBi-GABA on GABAA receptors of rat cerebellar granule cells in vitro. In particular, we evaluated the effects of side products obtained after RuBi-GABA photolysis. For this purpose, we developed a procedure to separate the “RuBi-cage” from GABA after uncaging RuBi-GABA with a laser source; then, we compared electrophysiological measurements acquired with and without administering the RuBi-cage in the perfusing bath. In conclusion, to investigate the role of the “cage” molecules both near and far from the cell soma, we compared experiments performed changing the distance of the uncaging point from the cell.

Journey on VX-809-Based Hybrid Derivatives towards Drug-like F508del-CFTR Correctors: From Molecular Modeling to Chemical Synthesis and Biological Assays

Cystic fibrosis (CF) is a genetic disease affecting the lungs and pancreas and causing progressive damage. CF is caused by mutations abolishing the function of CFTR, a protein whose role is chloride’s mobilization in the epithelial cells of various organs. Recently a therapy focused on small molecules has been chosen as a main approach to contrast CF, designing and synthesizing compounds acting as misfolding (correctors) or defective channel gating (potentiators). Multi-drug therapies have been tested with different combinations of the two series of compounds. Previously, we designed and characterized two series of correctors, namely, hybrids, which were conceived including the aminoarylthiazole (AAT) core, merged with the benzodioxole carboxamide moiety featured by VX-809. In this paper, we herein proceeded with molecular modeling studies guiding the design of a new third series of hybrids, featuring structural variations at the thiazole moiety and modifications on position 4. These derivatives were tested in different assays including a YFP functional assay on models F508del-CFTR CFBE41o-cells, alone and in combination with VX-445, and by using electrophysiological techniques on human primary bronchial epithelia to demonstrate their F508del-CFTR corrector ability. This study is aimed (i) at identifying three molecules (9b, 9g, and 9j), useful as novel CFTR correctors with a good efficacy in rescuing the defect of F508del-CFTR; and (ii) at providing useful information to complete the structure–activity study within all the three series of hybrids as possible CFTR correctors, supporting the development of pharmacophore modelling studies, taking into account all the three series of hybrids. Finally, in silico evaluation of the hybrids pharmacokinetic (PK) properties contributed to highlight hybrid developability as drug-like correctors.

Comparison of Different Commercial Nanopolystyrenes: Behavior in Exposure Media, Effects on Immune Function and Early Larval Development in the Model Bivalve Mytilus galloprovincialis

In the absence of standard methods for the detection/quantification of nanoplastics (NPs) in environmental samples, commercial nanopolymers are utilized as proxies for toxicity testing and environmental risk assessment. In marine species, a considerable amount of data are now available on the effects of nanopolystyrene (PS-NPs) of different size/surface characteristics. In this work, amino modified PS-NPs (PS-NH2) (50 and 100 nm), purchased from two different companies, were compared in terms of behavior in exposure media and of biological responses, from molecular to organism level, in the model marine bivalve Mytilus. Different PS-NH2 showed distinct agglomeration and surface charge in artificial sea water (ASW) and hemolymph serum (HS). Differences in behavior were largely reflected by the effects on immune function in vitro and in vivo and on early larval development. Stronger effects were generally observed with PS-NH2 of smaller size, showing less agglomeration and higher positive charge in exposure media. Specific molecular interactions with HS components were investigated by the isolation and characterization of the NP-corona proteins. Data obtained in larvae demonstrate interference with the molecular mechanisms of shell biogenesis. Overall, different PS-NH2 can affect the key physiological functions of mussels at environmental concentrations (10 µg/L). However, detailed information on the commercial NPs utilized is required to compare their biological effects among laboratory experiments.

Expanding the Occurrence of Polysaccharides to the Viral World: The Case of Mimivirus

The general perception of viruses is that they are small in terms of size and genome, and that they hijack the host machinery to glycosylate their capsid. Giant viruses subvert all these concepts: their particles are not small, and their genome is more complex than that of some bacteria. Regarding glycosylation, this concept has been already challenged by the finding that Chloroviruses have an autonomous glycosylation machinery that produces oligosaccharides similar in size to those of small viruses (6-12 units), albeit different in structure compared to the viral counterparts. We report herein that Mimivirus possesses a glycocalyx made of two different polysaccharides, now challenging the concept that all viruses coat their capsids with oligosaccharides of discrete size. This discovery contradicts the paradigm that such macromolecules are absent in viruses, blurring the boundaries between giant viruses and the cellular world and opening new avenues in the field of viral glycobiology.

CK2-mediated phosphorylation of Che-1/AATF is required for its pro-proliferative activity

Background

Che-1/AATF (Che-1) is an RNA polymerase II binding protein involved in several cellular processes, including proliferation, apoptosis and response to stress. We have recently demonstrated that Che-1 is able to promote cell proliferation by sustaining global histone acetylation in multiple myeloma (MM) cells where it interacts with histone proteins and competes with HDAC class I members for binding.

Methods

Site-directed Mutagenesis was performed to generate a Che-1 mutant (Che-1 3S) lacking three serine residues (Ser³¹⁶, Ser³²⁰ and Ser³²¹) in 308–325 aa region. Western blot experiments were conducted to examine the effect of depletion or over-expression of Che-1 and Che-1 3S mutant on histone acetylation, in different human cancer cell lines. Proliferation assays were assessed to estimate the change in cells number when Che-1 was over-expressed or deleted. Immunoprecipitation assays were performed to evaluate Che-1/histone H3 interaction when Ser³¹⁶, Ser³²⁰ and Ser³²¹ were removed. The involvement of CK2 kinase in Che-1 phosphorylation at these residues was analysed by in vitro kinase, 2D gel electrophoresis assays and mass spectrometry analysis.

Results

Here, we confirmed that Che-1 depletion reduces cell proliferation with a concomitant general histone deacetylation in several tumor cell lines. Furthermore, we provided evidence that CK2 protein kinase phosphorylates Che-1 at Ser³¹⁶, Ser³²⁰ and Ser³²¹ and that these modifications are required for Che-1/histone H3 binding. These results improve our understanding onto the mechanisms by which Che-1 regulates histone acetylation and cell proliferation.

Conclusions

Che-1 phosphorylation at Ser³¹⁶, Ser³²⁰ and Ser³²¹ by CK2 promotes the interaction with histone H3 and represents an essential requirement for Che-1 pro-proliferative ability.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02038-x.

Protein kinase G phosphorylates the Alzheimer's disease-associated tau protein at distinct Ser/Thr sites

Intraneuronal accumulation of hyperphosphorylated tau is a pathological hallmark of several neurodegenerative disorders, including Alzheimer's disease. Phosphorylation plays a crucial role in modulating the tau-microtubule interaction and the ability of the protein to aggregate, but despite efforts during the past decades, the real identity of the kynases involved in vivo remains uncertain. Here, for the first time, we demonstrate that the cGMP-dependent protein kinase G (PKG) phosphorylates tau in both in vitro and in vivo models. More intriguingly, we provide evidence that PKG phosphorylates tau at Ser214 but not at Ser202, a condition that could reduce the pathological aggregation of the protein shifting tau from a pro-aggregant to a neuroprotective anti-aggregant conformation.

The Remarkable Antioxidant and Anti-Inflammatory Potential of the Extracts of the Brown Alga Cystoseira amentacea var. stricta

Inflammation and oxidative stress are part of the complex biological responses of body tissues to harmful stimuli. In recent years, due to the increased understanding that oxidative stress is implicated in several diseases, pharmaceutical industries have invested in the research and development of new antioxidant compounds, especially from marine environment sources. Marine seaweeds have shown the presence of many bioactive secondary metabolites, with great potentialities from both the nutraceutical and the biomedical point of view. In this study, 50%-ethanolic and DMSO extracts from the species C. amentacea var. stricta were obtained for the first time from seaweeds collected in the Ligurian Sea (north-western Mediterranean). The bioactive properties of these extracts were then investigated, in terms of quantification of specific antioxidant activities by relevant ROS scavenging spectrophotometric tests, and of anti-inflammatory properties in LPS-stimulated macrophages by evaluation of inhibition of inflammatory cytokines and mediators. The data obtained in this study demonstrate a strong anti-inflammatory effect of both C. amentacea extracts (DMSO and ethanolic). The extracts showed a very low grade of toxicity on RAW 264.7 macrophages and L929 fibroblasts and a plethora of antioxidant and anti-inflammatory effects that were for the first time thoroughly investigated. The two extracts were able to scavenge OH and NO radicals (OH EC50 between 392 and 454 μg/mL; NO EC50 between 546 and 1293 μg/mL), to partially rescue H2O2-induced RAW 264.7 macrophages cell death, to abate intracellular ROS production in H2O2-stimulated macrophages and fibroblasts and to strongly inhibit LPS-induced inflammatory mediators, such as NO production and IL-1α, IL-6, cyclooxygenase-2 and inducible NO synthase gene expression in RAW 264.7 macrophages. These results pave the way, for the future use of C. amentacea metabolites, as an example, as antioxidant food additives in antiaging formulations as well as in cosmetic lenitive lotions for inflamed and/or damaged skin.

Protective effects of extracts from Ephedra foeminea Forssk fruits against oxidative injury in human endothelial cells

ETHNOPHARMACOLOGICAL RELEVANCE

Ephedra foeminea is a member of the Ephedraceae family which is widespread in the eastern Mediterranean area. In Lebanon, Ephedra is a popular remedy in traditional medicine to prevent and/or counteract many stress oxidative-related diseases like inflammation and bacterial infections.

AIM OF THE STUDY

Oxidative stress leads to endothelial cell dysfunction, and is a major factor contributing to etiology of atherosclerosis and related diseases. This study aims to investigate the antioxidant and cytoprotective potential of extracts from E. foeminea fruits on human endothelial cells exposed to hydrogen peroxide (H₂O₂) to mimic in vitro vascular endothelium dysfunction.

MATERIALS AND METHODS

Different extracts of E. foeminea fruits were prepared using pure ethanol (EE), methanol/water (EMW), pure hexane (Ehex) or ethyl acetate/water (Epoly) as extraction solvents. The phenolome profile of each extract was characterized using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS). Total phenolic and flavonoid content, and radical scavenging properties of the extracts were assessed spectrophotometrically. Then, the effects on human endothelial cells HECV were evaluated.

RESULTS

Epoly extract showed the highest phenol and flavonoid content, and the highest radical scavenging capacity. On H₂O₂-insulted HECV cells Epoly was able: (i) to counteract the ROS/RNS production and lipid peroxidation; (ii) to rescue the ROS-dependent decrease in the mitochondrial membrane potential; (iii) to counteract the apoptosis induction; (iv) to restore endothelial cell viability and migration.

CONCLUSIONS

The findings indicated that the polyphenol-enriched extract Epoly from E. foeminea fruits is endowed with in vitro anti-oxidant and anti-apoptotic effects and might be used as nutraceutical for treating ROS-related endothelium dysfunction and inflammation.

A Bioactive Olive Pomace Extract Prevents the Death of Murine Cortical Neurons Triggered by NMDAR Over-Activation

We have recently demonstrated that bioactive molecules, extracted by high pressure and temperature from olive pomace, counteract calcium-induced cell damage to different cell lines. Here, our aim was to study the effect of the same extract on murine cortical neurons, since the preservation of the intracellular Ca²⁺-homeostasis is essential for neuronal function and survival. Accordingly, we treated neurons with different stimuli in order to evoke cytotoxic glutamatergic activation. In these conditions, the high-pressure and temperature extract from olive pomace (HPTOPE) only abolished the effects of N-methyl-d-aspartate (NMDA). Particularly, we observed that HPTOPE was able to promote the neuron rescue from NMDA-induced cell death. Moreover, we demonstrated that HPTOPE is endowed with the ability to maintain the intracellular Ca²⁺-homeostasis following NMDA receptor overactivation, protecting neurons from Ca²⁺-induced adverse effects, including aberrant calpain proteolytic activity. Moreover, we highlight the importance of the extraction conditions used that, without producing toxic molecules, allow us to obtain protecting molecules belonging to proanthocyanidin derivatives like procyanidin B2. In conclusion, we can hypothesize that HPTOPE, due to its functional and nontoxic properties on neuronal primary culture, can be utilized for future therapeutic interventions for neurodegeneration.

Dysregulation in B-cell responses and T follicular helper cell function in ADA2 deficiency patients

Adenosine deaminase 2 deficiency (DADA2) is an autoinflammatory disease characterized by inflammatory vasculopathy, early strokes associated often with hypogammaglobulinemia. Pure red cell aplasia, thrombocytopenia, and neutropenia have been reported. The defect is due to biallelic loss of function of ADA2 gene, coding for a protein known to regulate the catabolism of extracellular adenosine. We therefore investigated immune phenotype and B- and T-cell responses in 14 DADA2 patients to address if ADA2 mutation affects B- and T-cell function. Here, we show a significant decrease in memory B cells, in particular class switch memory, and an expansion of CD21^low B cells in DADA2 patients. In vitro stimulated B lymphocytes were able to secrete nonfunctional ADA2 protein, suggesting a cell intrinsic defect resulting in an impairment of B-cell proliferation and differentiation. Moreover, CD4⁺ and CD8⁺ T cells were diminished; however, the frequency of circulating T follicular helper cells was significantly increased but they had an impairment in IL-21 production possibly contributing to an impaired B cell help. Our findings suggest that ADA2 mutation could lead to a B-cell intrinsic defect but also to a defective Tfh cell function, which could contribute to the immunodeficient phenotype reported in DADA2 patients.

Identification, Purification and Molecular Characterization of Chondrosin, a New Protein with Anti-tumoral Activity from the Marine Sponge Chondrosia Reniformis Nardo 1847

: Chondrosia reniformis is a common marine demosponge showing many peculiarities, lacking silica spicules and with a body entirely formed by a dense collagenous matrix. In this paper, we have described the identification of a new cytotoxic protein (chondrosin) with selective activity against specific tumor cell lines, from C. reniformis, collected from the Liguria Sea. Chondrosin was extracted and purified using a salting out approach and molecular weight size exclusion chromatography. The cytotoxic fractions were then characterized by two-dimensional gel electrophoresis and mass spectrometry analysis and matched the results with C. reniformis transcriptome database. The procedure allowed for identifying a full-length cDNA encoding for a 199-amino acids (aa) polypeptide, with a signal peptide of 21 amino acids. The mature protein has a theoretical molecular weight of 19611.12 and an IP of 5.11. Cell toxicity assays showed a selective action against some tumor cell lines (RAW 264.7 murine leukemia cells in particular). Cell death was determined by extracellular calcium intake, followed by cytoplasmic reactive oxygen species overproduction. The in silico modelling of chondrosin showed a high structural homology with the N-terminal region of the ryanodine receptor/channel and a short identity with defensin. The results are discussed suggesting a possible specific interaction of chondrosin with the Cav 1.3 ion voltage calcium channel expressed on the target cell membranes.

Cannabis-like activity of Zornia latifolia Sm. detected in vitro on rat cortical neurons: major role of the flavone syzalterin

Zornia latifolia is a plant suspected to possess psychoactive properties and marketed as a marijuana substitute under the name 'maconha brava'. In this study, the effects of fractions obtained from a 2-propanol extract of aerial portions of the plant were determined by multielectrode array (MEA) analyses on cultured networks of rat cortical neurons. Lipophilic (ZL_lipo, mainly containing flavonoid aglycones), and hydrophilic (ZL_hydro, mainly containing flavonoid glycosides) fractions were initially obtained from the raw extract. ZL_lipo significantly inhibited mean firing rate (MFR) and mean bursting rate (MBR) of MEA recordings, while ZL_hydro induced no inhibition. Column chromatography separation of ZL_lipo yielded five fractions (ZL1-ZL5), among which ZL1 induced the strongest MFR and MBR inhibition. NMR and HPLC-MS analyses of ZL1 revealed the prevalence of the common flavonoids genistein (1) and apigenin (2) (in about a 1:1 ratio), and the presence of the rare flavone syzalterin (6,8-dimethylapigenin) (3) as a minor compound. Exposures of MEA to apigenin and genistein standards did not induce the MFR and MBR inhibition observed with ZL1, whereas exposure to syzalterin standard or to a 1:9 mixture syzalterin-genistein induced effects similar to ZL1. These inhibitory effects were comparable to that observed with high-THC hashish, possibly accounting for the plant psychoactive properties. Data indicate that Z. latifolia, currently marketed as a free herbal product, should be subjected to measures of control. In addition, syzalterin showed distinctive pharmacological properties, opening the way to its possible exploitation as a neuroactive drug.

New acetylenic metabolites from the toxic mushroom Tricholoma pardinum

Four unprecedented acetylenic alcohols, (Z)-non-7-en-5-yn-1,2,4-triol (1), (Z)-non-7-en-5-yn-1,4-diol (2), (Z)-1,2-dihydroxynon-7-en-5-yn-4-one (3), and (Z)-1-hydroxynon-7-en-5-yn-4-one (4) were isolated from the poisonous mushroom Tricholoma pardinum (Agaricales, Basidiomycota), together with the known compounds 1H-indole-3-carbaldehyde (5) and 6-hydroxy-1H-indole-3-carbaldehyde (6). Their structures were determined by NMR and IR spectroscopy, and mass spectrometry. The crude acetone extract of the mushroom showed potent anti-arthropod activity against Tetranychus urticae (Acarinae), a dangerous crop pest.

Fibrinogen αC-regions are not directly involved in fibrin polymerization as evidenced by a "Double-Detroit" recombinant fibrinogen mutant and knobs-mimic peptides

BACKGROUND

Fibrin polymerization, following fibrinopeptides A and B (FpA, FpB) cleavage, relies on newly exposed α- and β-chains N-termini (GPR, GHR; A-, B-knobs, respectively) engaging preexistent a and b pockets in other fibrin(ogen) molecules' γ- and (B)β-chains C-terminal regions. A role for mostly disordered (A)α-chains C-terminal regions "bridging" between fibrin molecules/fibrils has been proposed.

OBJECTIVES

Fibrinogen Detroit is a clinically observed mutation (AαR19 → S) with nonengaging GPS A-knobs. By analogy, a similar Bβ-chain mutation, BβR17 → S, should produce nonengaging GHS B-knobs. A homozygous "Double-Detroit" mutant (AαR19 → S, BβR17 → S; DD-FG) was developed: with A-a and B-b engagements endogenously blocked, other interactions would become apparent.

METHODS

DD-FG, wild-type recombinant (WT-FG), and human plasma (hp-FG) fibrinogen self-association was studied by turbidimetry coupled with fibrinopeptides release high-performance liquid chromatography (HPLC)/mass spectrometry analyses, and by light-scattering following size-exclusion chromatography (SE-HPLC).

RESULTS

In contrast to WT-FG and hp-FG, DD-FG produced no turbidity increase, irrespective of thrombin concentration. The SE-HPLC profile of concentrated DD-FG was unaffected by thrombin treatment, and light-scattering, at lower concentration, showed no intensity and hydrodynamic radius changes. Compared with hp-FG, both WT-FG and DD-FG showed no FpA cleavage difference, while ~50% FpB was not recovered. Correspondingly, SDS-PAGE/Western-blots revealed partial Bβ-chain N-terminal and Aα-chain C-terminal degradation. Nevertheless, ~70% DD-FG molecules bearing (A)αC-regions potentially able to associate were available. Higher-concentration, nearly intact hp-FG with 500-fold molar excess GPRP-NH2 /GHRP-NH2 knobs-mimics experiments confirmed these no-association findings.

CONCLUSIONS

(A)αC-regions interactions appear too weak to assist native fibrin polymerization, at least without knobs engagement. Their role in all stages should be carefully reconsidered.

Synthesis and Structure-activity Relationship of Aminoarylthiazole Derivatives as Potential Potentiators of the Chloride Transport Defect in Cystic Fibrosis

BACKGROUND

Cystic fibrosis (CF) is the autosomal recessive disorder most common in Caucasian populations. It is caused by mutations in the cystic fibrosis transmembrane regulator protein (CFTR). CFTR is predominantly expressed at the apical plasma membranes of the epithelial cells lining several organs, and functions as a cAMP-regulated chloride/bicarbonate channel. To address the underlying causes of cystic fibrosis, two biomolecular activities are required, namely correctors to increase CFTR levels at the cell surface, and potentiators to allow the effective opening of the CFTR channel.

OBJECTIVE

In our previous data, we demonstrated that some aminoarylthiazoles (AATs) have peculiar activity acting as correctors and as potentiator-like molecules. Curiously, a compound called 1 has been shown to be markedly active as a potentiator. Now, we have further modified its scaffold at different portions, for the identification of molecules with improved potency and effectiveness on mutant CFTR.

METHODS

Starting from this active compound, we synthesized a small library trying to improve the activity as potentiators. To extrapolate the contribution of a particular structural portion to bioactivity, we selectively modified one portion at a time.

RESULTS

Our study has provided a structure-activity relationship (SAR) on AATs and led to the identification of some compounds, with a particular ability to act as CFTR potentiators.

CONCLUSION

Two compounds 2 and 13 appear to be promising molecules and could be used for the future development of potentiators of the chloride transport defect in cystic fibrosis.

Nanoformulated Zoledronic Acid Boosts the Vδ2 T Cell Immunotherapeutic Potential in Colorectal Cancer

Aminobisphosphonates, such as zoledronic acid (ZA), have shown potential in the treatment of different malignancies, including colorectal carcinoma (CRC). Yet, their clinical exploitation is limited by their high bone affinity and modest bioavailability. Here, ZA is encapsulated into the aqueous core of spherical polymeric nanoparticles (SPNs), whose size and architecture resemble that of biological vesicles. On Vδ2 T cells, derived from the peripheral blood of healthy donors and CRC patients, ZA-SPNs induce proliferation and trigger activation up to three orders of magnitude more efficiently than soluble ZA. These activated Vδ2 T cells kill CRC cells and tumor spheroids, and are able to migrate toward CRC cells in a microfluidic system. Notably, ZA-SPNs can also stimulate the proliferation of Vδ2 T cells from the tumor-infiltrating lymphocytes of CRC patients and boost their cytotoxic activity against patients' autologous tumor organoids. These data represent a first step toward the use of nanoformulated ZA for immunotherapy in CRC patients.

Aquaporin-9 is involved in the lipid-lowering activity of the nutraceutical silybin on hepatocytes through modulation of autophagy and lipid droplets composition

Hepatic steatosis is the hallmark of non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of the metabolic syndrome and insulin resistance with potential evolution towards non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma. Key roles of autophagy and oxidative stress in hepatic lipid accumulation and NAFLD progression are recognized. Here, we employed a rat hepatoma cell model of NAFLD progression made of FaO cells exposed to oleate/palmitate followed or not by TNFα treatment to investigate the molecular mechanisms through which silybin, a lipid-lowering nutraceutical, may improve hepatic lipid dyshomeostasis. The beneficial effect of silybin was found to involve amelioration of the fatty acids profile of lipid droplets, stimulation of the mitochondrial oxidation and upregulation of a microRNA of pivotal relevance in hepatic fat metabolism, miR-122. Silybin was also found to restore the levels of Aquaporin-9 (AQP9) and glycerol permeability while reducing the activation of the oxidative stress-dependent transcription factor NF-κB, and autophagy turnover. In conclusion, silybin was shown to have molecular effects on signaling pathways that were previously unknown and potentially protect the hepatocyte. These actions intersect TG metabolism, fat-induced autophagy and AQP9-mediated glycerol transport in hepatocytes.

Antisteatotic and antioxidant activities of Thymbra spicata L. extracts in hepatic and endothelial cells as in vitro models of non-alcoholic fatty liver disease

ETHNOPHARMACOLOGICAL RELEVANCE

Thymbra spicata, a member of the Lamiaceae family, is native to eastern Mediterranean area. Leaves of this plant are rich in phenolic compounds and are a popular remedy of traditional medicine in Lebanon to prevent and/or counteract hyperlipidemia and hyperglycemia.

AIM OF THE STUDY

To evaluate the antisteatotic and antioxidant activities of extracts from leaves of Thymbra spicata L. using in vitro models of non-alcoholic fatty liver disease (NAFLD), a leading cause of liver-related morbidity and mortality worldwide, for whom no effective treatments are still available.

MATERIALS AND METHODS

Two different extracts from Thymbra spicata L. aerial parts were prepared using water (TW) or ethanol (TE) as solvent. Their chemical composition was characterized by gas and liquid chromatography coupled with mass spectrometry. Both extracts were tested on cultured hepatic and endothelial cells treated to mimic in vitro a multisistemic pathology such as NAFLD. We assayed the effects on lipid accumulation, free radical production, lipid peroxidation, cell migration.

RESULTS

Both the total phenolic and the total flavonoid contents were higher in the ethanolic extract. Rosmarinic acid was the most abundant polyphenol in TW, while TE was richer in carvacrol. Our findings demonstrated that both extracts ameliorated lipid accumulation, oxidative stress and inflammation in the NAFLD cellular models. However, the aqueous extract was more effective to reduce hepatic steatosis, and the ethanolic extract had higheranti-oxidant potential and wound healing activity.

CONCLUSIONS

T. spicata extracts could be promising bioactive products to develop natural therapeutic agents or dietary supplements to treat NAFLD and obesity-related metabolic disease. Our findings suggest that while the ethanolic extract might be used in preventing endothelium dysfunction, the aqueous extract would act better as lipid-lowering agent.

It's Only a Part of the Story: Analytical Investigation of the Inks and Dyes Used in the Privilegium Maius

The Privilegium maius is one of the most famous and spectacular forgeries in medieval Europe. It is a set of charters made in the 14th century upon commitment by Duke Rudolf IV, a member of the Habsburg family, to elevate the rank and the prestige of his family. These five charters, now kept at the Österreichisches Staatsarchiv in Vienna, have been subjected to a thorough interdisciplinary study in order to shed light on its controversial story. The charters are composed of pergamenaceous documents bound to wax seals with coloured textile threads. The present contribution concerns the characterisation of the inks used for writing and of the dyes used to colour to the threads: Are they compatible with the presumed age of the charters? Though showing only a part of the whole story of the charters, dyes analysis could contribute in assessing their complex history from manufacturing to nowadays. The dyes were characterised with non-invasive in situ measurements by means of fibre optic (FORS) and with micro-invasive measurements by means of Surface Enhanced Raman Spectroscopy (SERS) and High-Performance Liquid Chromatography with Mass Spectrometry (HPLC-MS) analysis. The results showed that the threads of four of the charters (three dyed with madder, one with orchil) were apparently coloured at different dyeing stages, then re-dyed in the 19–20th century.

Elicited ROS Scavenging Activity, Photoprotective, and Wound-Healing Properties of Collagen-Derived Peptides from the Marine Sponge Chondrosia reniformis

Recently, the bioactive properties of marine collagen and marine collagen hydrolysates have been demonstrated. Although there is some literature assessing the general chemical features and biocompatibility of collagen extracts from marine sponges, no data are available on the biological effects of sponge collagen hydrolysates for biomedical and/or cosmetic purposes. Here, we studied the in vitro toxicity, antioxidant, wound-healing, and photoprotective properties of four HPLC-purified fractions of trypsin-digested collagen extracts-marine collagen hydrolysates (MCHs)-from the marine sponge C. reniformis. The results showed that the four MCHs have no degree of toxicity on the cell lines analyzed; conversely, they were able to stimulate cell growth. They showed a significant antioxidant activity both in cell-free assays as well as in H₂O₂ or quartz-stimulated macrophages, going from 23% to 60% of reactive oxygen species (ROS) scavenging activity for the four MCHs. Finally, an in vitro wound-healing test was performed with fibroblasts and keratinocytes, and the survival of both cells was evaluated after UV radiation. In both experiments, MCHs showed significant results, increasing the proliferation speed and protecting from UV-induced cell death. Overall, these data open the way to the use of C. reniformis MCHs in drug and cosmetic formulations for damaged or photoaged skin repair.

Estimates of Environmental Exposure to Radiofrequency Electromagnetic Fields and Risk of Lymphoma Subtypes

We investigated the association between environmental exposure to radiofrequency electromagnetic fields (RF-EMF) and risk of lymphoma subtypes in a case-control study comprised of 322 patients and 444 individuals serving as controls in Sardinia, Italy in 1998-2004. Questionnaire information included the self-reported distance of the three longest held residential addresses from fixed radio-television transmitters and mobile phone base stations. We georeferenced the residential addresses of all study subjects and obtained the spatial coordinates of mobile phone base stations. For each address within a 500-meter radius from a mobile phone base station, we estimated the RF-EMF intensity using predictions from spatial models, and we performed RF-EMF measurements at the door in the subset of the longest held addresses within a 250-meter radius. We calculated risk of lymphoma and its major subtypes associated with the RF-EMF exposure metrics with unconditional logistic regression, adjusting by age, gender and years of education. In the analysis of self-reported data, risk associated with residence in proximity (within 50 meters) to fixed radio-television transmitters was likewise elevated for lymphoma overall [odds ratio = 2.7, 95% confidence interval = 1.5-4.6], and for the major lymphoma subtypes. With reference to mobile phone base stations, we did not observe an association with either the self-reported, or the geocoded distance from mobile phone base stations. RF-EMF measurements did not vary by case-control status. By comparing the self-reports to the geocoded data, we discovered that the cases tended to underestimate the distance from mobile phone base stations differentially from the controls ( P = 0.073). The interpretation of our findings is compromised by the limited study size, particularly in the analysis of the individual lymphoma subtypes, and the unavailability of the spatial coordinates of radio-television transmitters. Nonetheless, our results do not support the hypothesis of a link between environmental exposure to RF-EMF from mobile phone base stations and risk of lymphoma subtypes.

Posidonia oceanica (L.) Delile Ethanolic Extract Modulates Cell Activities with Skin Health Applications

Seagrasses are high plants sharing adaptive metabolic features with both terrestrial plants and marine algae, resulting in a phytocomplex possibly endowed with interesting biological properties. The aim of this study is to evaluate the in vitro activities on skin cells of an ethanolic extract obtained from the leaves of Posidonia oceanica (L.) Delile, family Potamogetonaceae, herein named Posidonia ethanolic extract (PEE). PEE showed high radical scavenging activity, high phenolic content, and resulted rich in chicoric acid, as determined through HPLC-MS analysis. The use of MTT assay on fibroblasts showed a PEE cytotoxicity threshold (IC₀₅) of 50 µg/mL at 48 h, while a sub-toxic dose of 20 µg/mL induced a significant increase of fibroblast growth rate after 10 days. In addition, an ELISA assay revealed that PEE doses of 5 and 10 µg/mL induced collagen production in fibroblasts. PEE induced dose-dependent mushroom tyrosinase inhibition, up to about 45% inhibition at 1000 µg/mL, while 50% reduction of melanin was observed in melanoma cells exposed to 50 µg/mL PEE. Finally, PEE lipolytic activity was assessed by measuring glycerol release from adipocytes following triglyceride degradation. In conclusion, we have collected new data about the biological activities of the phytocomplex of P. oceanica seagrass on skin cells. Our findings indicate that PEE could be profitably used in the development of products for skin aging, undesired hyperpigmentation, and cellulite.

The bioactivity of Hedysarum coronarium extracts on skin enzymes and cells correlates with phenolic content

CONTEXT

The search for bioactive compounds from botanical sources is attracting much interest. However, differences in chemical composition may occur within the same species depending on different geographical origins.

OBJECTIVES

We evaluated the properties on skin enzymes and cells of extracts from sulla legume crop Hedysarum coronarium L. (Fabaceae), collected at two Italian sites near Pisa and Ventimiglia, for possible dermatological and cosmetic applications.

MATERIAL AND METHODS

Plant aerial portions were extracted in MTBE/ethyl acetate/acetone, obtaining two extracts named Pisa sulla extract (PSE) and Ventimiglia sulla extract (VSE). Extracts were subjected to chemical characterization, LC-MS/MS analysis and biological assays.

RESULTS

PSE showed stronger antiradical scavenging and higher phenolic and flavonoid contents with respect to VSE. LC-MS/MS analysis revealed similar composition for the two extracts, but PSE was richer in condensed tannins and flavonoids, principally rhoifolin, quercetin, naringenin and derivatives. PSE induced stronger inhibition on collagenase and elastase by in vitro enzyme assays, possibly due to higher levels of condensed tannins and quercetin. ELISA bioassay on human dermal fibroblasts revealed stronger PSE induction of collagen production. Determination of glycerol release from adipocytes disclosed stronger stimulation of lipolysis by PSE, allegedly ascribed to higher charge of quercetin and derivatives. In summary, the higher richness in phenolics of PSE is strictly related to stronger bioactivity.

DISCUSSION AND CONCLUSIONS

Data indicate that aerial H. coronarium material is suitable for the development of dermatological and cosmeceutical products, but the geographical origin is an important factor for maximally exploiting the biological properties of this species.

A Novel Method to Synthesize Phosphocreatine and Phosphocreatine Prodrugs

BACKGROUND

Adenosine triphosphate (ATP) is the energy currency of the body; it takes part in various and indispensable metabolic processes for the maintenance of cell homeostasis, degrading to its hydrolysis product, adenosine diphosphate (ADP). Efficient ways to restore ATP are therefore necessary in the cells. When the cell lacks energy due to ischemic conditions or high ATP demand, phosphocreatine gives its phosphate group to ADP that converts to ATP, in a reaction catalyzed by the enzyme creatine kinase. For this reason, phosphocreatine is utilized as a pharmacological treatment in human diseases that involve a failure of the cellular energy, most notably in coronary artery disease.

OBJECTIVE

Commercially available phosphocreatine is currently synthesized using different methods, each of one characterized by a rather low yield of the final product, probably due to the low reactivity of the guanylating reagent. The aim of this work is to overcome the drawbacks of the synthetic methods currently employed, devising a novel synthetic route to obtain phosphocreatine and phosphocreatine prodrugs in higher yields and purity.

METHOD

To obtain a higher yield of the final product and a lower number of sub-products, this method utilizes a new guanylating agent characterized by high reactivity, endowed with a protecting group t-Boc on one of the two nitrogen atoms of the guanidinic function and a protected phosphate on the other one; that compound is then conjugated with an opportune secondary amine. The obtained product is cleaved first with acidic conditions to obtain the phosphocreatine prodrug (phosphocreatine ethyl ester) and then with an enzymatic method to obtain the phosphocreatine.

RESULT

Have been obtained in good yield and purity as demonstrated by HPLC and mass spectrometry analysis.

CONCLUSION

This novel synthetic route permits to obtain the phosphocreatine molecule in higher yield and purity compared to the methods currently employed with a combination of chemical and enzymatic methods.

SIRT6 inhibitors with salicylate-like structure show immunosuppressive and chemosensitizing effects

The NAD⁺-dependent deacetylase SIRT6 is an emerging cancer drug target, whose inhibition sensitizes cancer cells to chemo-radiotherapy and has pro-differentiating effects. Here we report on the identification of novel SIRT6 inhibitors with a salicylate-based structure. The new SIRT6 inhibitors show improved potency and specificity compared to the hit inhibitor identified in an in silico compound screen. As predicted based on SIRT6 biological roles, the new leads increase histone 3 lysine 9 acetylation and glucose uptake in cultured cells, while blocking TNF-α production and T lymphocyte proliferation. Notably, the new SIRT6 inhibitors effectively sensitize pancreatic cancer cells to gemcitabine. Finally, studies of compound fingerprinting and pharmacokinetics defined the drug-like properties of one of the new SIRT6 inhibitors, potentially allowing for subsequent in vivo proof-of-concept studies. In conclusion, new SIRT6 inhibitors with a salicylate-like structure were identified, which are active in cells and could potentially find applications in disease conditions, including cancer and immune-mediated disorders.

The rare sugar N-acetylated viosamine is a major component of Mimivirus fibers

The giant virus Mimivirus encodes an autonomous glycosylation system that is thought to be responsible for the formation of complex and unusual glycans composing the fibers surrounding its icosahedral capsid, including the dideoxyhexose viosamine. Previous studies have identified a gene cluster in the virus genome, encoding enzymes involved in nucleotide-sugar production and glycan formation, but the functional characterization of these enzymes and the full identification of the glycans found in viral fibers remain incomplete. Because viosamine is typically found in acylated forms, we suspected that one of the genes might encode an acyltransferase, providing directions to our functional annotations. Bioinformatic analyses indicated that the L142 protein contains an N-terminal acyltransferase domain and a predicted C-terminal glycosyltransferase. Sequence analysis of the structural model of the L142 N-terminal domain indicated significant homology with some characterized sugar acetyltransferases that modify the C-4 amino group in the bacillosamine or perosamine biosynthetic pathways. Using mass spectrometry and NMR analyses, we confirmed that the L142 N-terminal domain is a sugar acetyltransferase, catalyzing the transfer of an acetyl moiety from acetyl-CoA to the C-4 amino group of UDP-d-viosamine. The presence of acetylated viosamine in vivo has also been confirmed on the glycosylated viral fibers, using GC-MS and NMR. This study represents the first report of a virally encoded sugar acetyltransferase.

Creatine salts provide neuroprotection even after partial impairment of the creatine transporter

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Creatine is a compound that is critical for energy metabolism of nervous cells.

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Creatine absence due to deficit of creatine transporter causes severe brain symptoms.

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Creatine crosses BBB and neuronal membrane slowly, and only using its transporter.

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Creatine derivatives may cross BBB and neuronal membrane without the transporter.

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Creatine derivatives may be a useful strategy in creatine transporter deficiency.

Creatine, a compound that is critical for energy metabolism of nervous cells, crosses the blood-brain barrier (BBB) and the neuronal plasma membrane with difficulty, and only using its specific transporter. In the hereditary condition where the creatine transporter is defective (creatine transporter deficiency) there is no creatine in the brain, and administration of creatine is useless lacking the transporter. The disease is severe and incurable. Creatine-derived molecules that could cross BBB and plasma membrane independently of the transporter might be useful to cure this condition. Moreover, such molecules could be useful also in stroke and other brain ischemic conditions. In this paper, we investigated three creatine salts, creatine ascorbate, creatine gluconate and creatine glucose. Of these, creatine glucose was ineffective after transporter block with guanidine acetic acid (GPA) administration. Creatine ascorbate was not superior to creatine in increasing tissue creatine and phosphocreatine content after transporter impairment, however even after such impairment it delayed synaptic failure during anoxia. Finally, creatine gluconate was superior to creatine in increasing tissue content of creatine after transporter block and slowed down PS disappearance during anoxia, an effect that creatine did not have. These findings suggest that coupling creatine to molecules having a specific transporter may be a useful strategy in creatine transporter deficiency. In particular, creatine ascorbate has effects comparable to those of creatine in normal conditions, while being superior to it under conditions of missing or impaired creatine transporter.

Interactions of cationic polystyrene nanoparticles with marine bivalve hemocytes in a physiological environment: Role of soluble hemolymph proteins

The bivalve Mytilus galloprovincialis has proven as a suitable model invertebrate for evaluating the potential impact of nanoparticles (NPs) in the marine environment. In particular, in mussels, the immune system represents a sensitive target for different types of NPs. In environmental conditions, both NP intrinsic properties and those of the receiving medium will affect particle behavior and consequent bioavailability/uptake/toxicity. However, the evaluation of the biological effects of NPs requires additional understanding of how, once within the organism, NPs interact at the molecular level with cells in a physiological environment. In mammalian systems, different NPs associate with serum soluble components, organized into a "protein corona", which affects particle interactions with target cells. However, no information is available so far on the interactions of NPs with biological fluids of aquatic organisms. In this work, the influence of hemolymph serum (HS) on the in vitro effects of amino modified polystyrene NPs (PS-NH2) on Mytilus hemocytes was investigated. Hemocytes were incubated with PS-NH2 suspensions in HS (1, 5 and 50µg/mL) and the results were compared with those obtained in ASW medium. Cell functional parameters (lysosomal membrane stability, oxyradical production, phagocytosis) were evaluated, and morphological changes were investigated by TEM. The activation state of the signalling components involved in Mytilus immune response (p38 MAPK and PKC) was determined. The results show that in the presence of HS, PS-NH2 increased cellular damage and ROS production with respect to ASW medium. The effects were apparently mediated by disregulation of p38 MAPK signalling. The formation of a PS-NH2-protein corona in HS was investigated by centrifugation, and 1D- gel electrophoresis and nano-HPLC-ESI-MS/MS. The results identified the Putative C1q domain containing protein (MgC1q6) as the only component of the PS-NH2 hard protein corona in Mytilus hemolymph. These data represent the first evidence for the formation of a NP bio-corona in aquatic organisms and underline the importance of the recognizable biological identity of NPs in physiological exposure medium when testing their potential impact environmental model organisms. Although the results obtained in vitro do not entirely reflect a realistic exposure scenario and the more complex formation of a bio-corona that is likely to occur in vivo, these data will contribute to a better understanding of the effects of NPs in marine invertebrates.

AIRE polymorphism, melanoma antigen-specific T cell immunity, and susceptibility to melanoma

AIRE is involved in susceptibility to melanoma perhaps regulating T cell immunity against melanoma antigens (MA). To address this issue, AIRE and MAGEB2 expressions were measured by real time PCR in medullary thymic epithelial cells (mTECs) from two strains of C57BL/6 mice bearing either T or C allelic variant of the rs1800522 AIRE SNP. Moreover, the extent of apoptosis induced by mTECs in MAGEB2-specific T cells and the susceptibility to in vivo melanoma B16F10 cell challenge were compared in the two mouse strains.The C allelic variant, protective in humans against melanoma, induced lower AIRE and MAGEB2 expression in C57BL/6 mouse mTECs than the T allele. Moreover, mTECs expressing the C allelic variant induced lower extent of apoptosis in MAGEB2-specific syngeneic T cells than mTECs bearing the T allelic variant (p < 0.05). Vaccination against MAGEB2 induced higher frequency of MAGEB2-specific CTL and exerted higher protective effect against melanoma development in mice bearing the CC AIRE genotype than in those bearing the TT one (p < 0.05). These findings show that allelic variants of one AIRE SNP may differentially shape the MA-specific T cell repertoire potentially influencing susceptibility to melanoma.

Note: Fractionation of Sheep Milk Fat Via Supercritical Carbon Dioxide

Supercritical carbon dioxide (SC-CO2) was used for anhydrous ovine milk fat (AMF) fractionation. Two different fractions were obtained: a low molecular weight triacylglycerol (TAG), named fraction E, and a high molecular weight TAG, termed fraction R. Fractionation was performed at different pressure and temperature values. The effect of these parameters on the chemical composition of the two fractions were analysed in relation to the original AMF. Among the searched conditions, 250 bar and 40°C gave the best fractionation results.

Note. Xylose Production from Durum Wheat Bran: Enzymic versus Chemical Methods

Both acidic and enzymic hydrolytic processes of durum wheat bran to obtain high xylose syrups are discussed in terms of yields and operative conditions. Mild sulphuric hydrolysis gave the best results (400mg of aldopentoses per gram of pre-extracted wheat bran within 4–6 h) whereas hydrochloric and especially phosphoric acids led to low yields. Preliminary work with a highly active recombinant xylanase (endoxylanase) led to deep solubilisation of arabinoxylans, mainly leading to oligosaccharides and their acyl (essentially feruloyl) derivatives. Mild sulphuric hydrolysis still seems to be the treatment of choice for xylose recovery from durum wheat bran.