Immune responses to oligomeric α-synuclein in Parkinson's disease peripheral blood mononuclear cells.

Parkinson's disease displays clinical heterogeneity, presenting with motor and non-motor symptoms. Heterogeneous phenotypes, named brain-first and body-first, may reflect distinct α-synuclein pathology starting either in the central nervous system or in the periphery. The immune system plays a prominent role in the central and peripheral pathology, with misfolded α-synuclein being placed at the intersection between neurodegeneration and inflammation. Here, we characterized the inflammatory profile and immune-phenotype of peripheral blood mononuclear cells (PBMCs) from Parkinson's disease patients upon stimulation with α-synuclein monomer or oligomer, and investigated relationships of immune parameters with clinical scores of motor and non-motor symptoms. Freshly isolated PBMCs from 21 Parkinson's disease patients and 18 healthy subjects were exposed in vitro to α-synuclein species. Cytokine/chemokine release was measured in the culture supernatant by Multiplex Elisa. The immune-phenotype was studied by FACS-flow cytometry. Correlation analysis was computed between immune parameters and parkinsonian motor and non-motor scales. We found that Parkinson's disease patients exhibited a dysregulated PBMC-cytokine profile, which remained unaltered after exposure to α-synuclein species and correlated with both motor and non-motor severity, with a strong correlation observed with olfactory impairment. Exposure of PBMCs from healthy controls to α-synuclein monomer/oligomer increased the cytokine/chemokine release up to patient's values. Moreover, the PBMCs immune phenotype differed between patients and controls and revealed a prominent association of the Mos profile with olfactory impairment, and of NK profile with constipation. Results suggest that a deranged PBMC-immune profile may reflect distinct clinical subtypes and would fit with the recent classification of Parkinson's disease into peripheral-first versus brain-first phenotype.

Protective Effect of Arzanol against H2O2-Induced Oxidative Stress Damage in Differentiated and Undifferentiated SH-SY5Y Cells.

Oxidative stress can damage neuronal cells, greatly contributing to neurodegenerative diseases (NDs). In this study, the protective activity of arzanol, a natural prenylated α-pyrone-phloroglucinol heterodimer, was evaluated against the H2O2-induced oxidative damage in trans-retinoic acid-differentiated (neuron-like) human SH-SY5Y cells, widely used as a neuronal cell model of neurological disorders. The pre-incubation (for 2 and 24 h) with arzanol (5, 10, and 25 µM) significantly preserved differentiated SH-SY5Y cells from cytotoxicity (MTT assay) and morphological changes induced by 0.25 and 0.5 mM H2O2. Arzanol reduced the generation of reactive oxygen species (ROS) induced by 2 h oxidation with H2O2 0.5 mM, established by 2',7'-dichlorodihydrofluorescein diacetate assay. The 2 h incubation of differentiated SH-SY5Y cells with H2O2 determined a significant increase in the number of apoptotic cells versus control cells, evaluated by propidium iodide fluorescence assay (red fluorescence) and NucView® 488 assay (green fluorescence). Arzanol pre-treatment (2 h) exerted a noteworthy significant protective effect against apoptosis. In addition, arzanol was tested, for comparison, in undifferentiated SH-SY5Y cells for cytotoxicity and its ability to protect against H2O2-induced oxidative stress. Furthermore, the PubChem database and freely accessible web tools SwissADME and pkCSM-pharmacokinetics were used to assess the physicochemical and pharmacokinetic properties of arzanol. Our results qualify arzanol as an antioxidant agent with potential neuroprotective effects against neuronal oxidative stress implicated in NDs.

Chemical Composition, Nutritional, and Biological Properties of Extracts Obtained with Different Techniques from Aronia melanocarpa Berries.

This study investigates the chemical composition, nutritional, and biological properties of extracts obtained from A. melanocarpa berries using different extraction methods and solvents. Hydrodistillation and supercritical fluid extraction with CO2 allowed us to isolate fruit essential oil (HDEX) and fixed oil (SFEEX), respectively. A phenol-enriched extract was obtained using a mild ultrasound-assisted maceration with methanol (UAMM). The HDEX most abundant component, using gas chromatography-mass spectrometry (GC/MS), was italicene epoxide (17.2%), followed by hexadecanoic acid (12.4%), khusinol (10.5%), limonene (9.7%), dodecanoic acid (9.7%), and (E)-anethole (6.1%). Linoleic (348.9 mg/g of extract, 70.5%), oleic (88.9 mg/g, 17.9%), and palmitic (40.8 mg/g, 8.2%) acids, followed by α-linolenic and stearic acids, were the main fatty acids in SFEEX determined using high-performance liquid chromatography coupled with a photodiode array detector and an evaporative light scattering detector (HPLC-DAD/ELSD). HPLC-DAD analyses of SFEEX identified ß-carotene as the main carotenoid (1.7 mg/g), while HPLC with fluorescence detection (FLU) evidenced α-tocopherol (1.2 mg/g) as the most abundant tocopherol isoform in SFEEX. Liquid chromatography-electrospray ionization-MS (LC-ESI-MS) analysis of UAMM showed the presence of quercetin-sulfate (15.6%, major component), malvidin 3-O-(6-O-p-coumaroyl) glucoside-4-vinylphenol adduct (pigment B) (9.3%), di-caffeoyl coumaroyl spermidine (7.6%), methyl-epigallocatechin (5.68%), and phloretin (4.1%), while flavonoids (70.5%) and phenolic acids (23.9%) emerged as the most abundant polyphenol classes. UAMM exerted a complete inhibition of the cholesterol oxidative degradation at 140 °C from 75 µg of extract, showing 50% protection at 30.6 µg (IA50). Furthermore, UAMM significantly reduced viability (31-48%) in A375 melanoma cells in the range of 500-2000 µg/mL after 96 h of incubation (MTT assay), with a low toxic effect in normal HaCaT keratinocytes. The results of this research extend the knowledge of the nutritional and biological properties of A. melanocarpa berries, providing useful information on specific extracts for potential food, cosmetic, and pharmaceutical applications.

Comparative Evaluation of Anticancer Activity of Natural Methoxylated Flavones Xanthomicrol and Eupatilin in A375 Skin Melanoma Cells.

Melanoma is a skin cancer caused by the malignant transformation of melanocytes and cutaneous melanoma represents the most aggressive and deadliest type of skin cancer with an increasing incidence worldwide. The main purpose of the present research was to evaluate the anticancer effects of the natural bioactive compounds xanthomicrol (XAN) and eupatilin (EUP) in human A375 malignant skin melanoma cells, a cell line widely used as an in vitro model of cutaneous melanoma. XAN and EUP are lipophilic methoxylated flavones with antioxidant, anti-inflammatory, and antitumor properties. The effects of XAN and EUP on cell viability, morphology, lipid profile, oxidative status, apoptosis, and mitochondrial membrane polarization were determined and compared in A375 cells. At 24 h-incubation (MTT assay), XAN significantly reduced viability at the dose range of 2.5-200 µM, while EUP showed a significant cytotoxicity from 25 µM. Moreover, both methoxylated flavones induced (at 10 and 25 µM, 24 h-incubation) marked cell morphological alterations (presence of rounded and multi-nucleated cells), signs of apoptosis (NucView 488 assay), and a noteworthy mitochondrial membrane depolarization (MitoView 633 assay), coupled to a marked lipid profile modulation, including variations in the ratio of phospholipid/cholesterol and a decrease in the oleic, palmitic, and palmitoleic acid amounts. Moreover, a remarkable time-dependent ROS generation (2',7'-dichlorodihydrofluorescein diacetate assay) was observed during 3 h-incubation of A375 cancer cells in the presence of XAN and EUP (10 and 25 µM). Our results confirm the potential antitumor effect of natural EUP and XAN in cutaneous melanoma by the activation of multiple anticancer mechanisms.

Arzanol, a natural phloroglucinol α-pyrone, protects HaCaT keratinocytes against H2O2-induced oxidative stress, counteracting cytotoxicity, reactive oxygen species generation, apoptosis, and mitochondrial depolarization.

Skin oxidative stress results in structural damage, leading to premature senescence, and pathological conditions such as inflammation and cancer. The plant-derived prenylated pyrone-phloroglucinol heterodimer arzanol, isolated from Helichrysum italicum ssp. microphyllum (Willd.) Nyman aerial parts, exhibits anti-inflammatory, anticancer, antimicrobial, and antioxidant activities. This study explored the arzanol protection against hydrogen peroxide (H2O2) induced oxidative damage in HaCaT human keratinocytes in terms of its ability to counteract cytotoxicity, reactive oxygen species (ROS) generation, apoptosis, and mitochondrial membrane depolarization. Arzanol safety on HaCaT cells was preliminarily examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and microscopic observation. The arzanol pre-incubation (5-100 µM, for 24 h) did not induce cytotoxicity and morphological alterations. The phloroglucinol, at 50 µM, significantly protected keratinocytes against cytotoxicity induced by 2 h-incubation with 2.5 and 5 mM H2O2, decreased cell ROS production induced by 1 h-exposure to all tested H2O2 concentrations (0.5-5 mM), as determined by the 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA) assay, and lipid peroxidation (thiobarbituric acid reactive substances [TBARS] method). The 2-h incubation of keratinocytes with H2O2 determined a significant increase of apoptotic cells versus control cells, evaluated by NucView® 488 assay, from the dose of 2.5 mM. Moreover, an evident mitochondrial membrane potential depolarization, monitored by fluorescent mitochondrial dye MitoView™ 633, was assessed at 5 mM H2O2. Arzanol pre-treatment (50 µM) exerted a strong significant protective effect against apoptosis, preserving the mitochondrial membrane potential of HaCaT cells at the highest H2O2 concentrations. Our results validate arzanol as an antioxidant agent for the prevention/treatment of skin oxidative-related disorders, qualifying its potential use for cosmeceutical and pharmaceutical applications.

Design of 3-Phenylcoumarins and 3-Thienylcoumarins as Potent Xanthine Oxidase Inhibitors: Synthesis, Biological Evaluation, and Docking Studies.

Coumarin scaffold has proven to be promising in the development of bioactive agents, such as xanthine oxidase (XO) inhibitors. Novel hydroxylated 3-arylcoumarins were designed, synthesized, and evaluated for their XO inhibition and antioxidant properties. 3-(3'-Bromophenyl)-5,7-dihydroxycoumarin (compound 11) proved to be the most potent XO inhibitor, with an IC50 of 91 nM, being 162 times better than allopurinol, one of the reference controls. Kinetic analysis of compound 11 and compound 5 [3-(4'-bromothien-2'-yl)-5,7-dihydroxycoumarin], the second-best compound within the series (IC50 of 280 nM), has been performed, and both compounds showed a mixed-type inhibition. Both compounds present good antioxidant activity (ability to scavenge ABTS radical) and are able to reduce reactive oxygen species (ROS) levels in H2 O2 -treated cells. In addition, they proved to be non-cytotoxic in a Caco-2 cells viability assay. Molecular docking studies have been carried out to correlate the compounds' theoretical and experimental binding affinity to the XO binding pocket.

Waste Citrus limon Leaves as Source of Essential Oil Rich in Limonene and Citral: Chemical Characterization, Antimicrobial and Antioxidant Properties, and Effects on Cancer Cell Viability.

This study investigated chemical composition, cytotoxicity in normal and cancer cells, and antimicrobial and antioxidant activity of the essential oil (EO) isolated by hydrodistillation from the discarded leaves of lemon (Citrus limon) plants cultivated in Sardinia (Italy). The volatile chemical composition of lemon leaf EO (LLEO) was analyzed with gas chromatography-mass spectrometry combined with flame ionization detection (GC/MS and GC/FID). The most abundant component of LLEO was limonene (260.7 mg/mL), followed by geranial (102.6 mg/mL) and neral (88.3 mg/mL). The antimicrobial activity of LLEO was tested using eight bacterial strains and two types of yeasts by a microdilution broth test. Candida albicans showed the greatest susceptibility (MIC = 0.625 µL/mL) and Listeria monocytogenes and Staphylococcus aureus were inhibited at low LLEO concentration (MIC values from 2.5 to 5 µL/mL). The C. limon leaf EO displayed radical scavenging ability (IC50 value of 10.24 mg/mL) in the 2,2-diphenyl-1-picryl-hydrazylhydrate (DPPH) assay. Furthermore, the LLEO impact on cell viability was explored by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in cancer HeLa cells, A375 melanoma cell line, normal fibroblasts (3T3 cells), and keratinocytes (HaCaT cells). LLEO, at 24 h of incubation, significantly reduced viability from 25 µM in Hela cells (33% reduction) and A375 cells (27%), greatly affecting cell morphology, whereas this effect was found from 50 µM on 3T3 fibroblasts and keratinocytes. LLEO's pro-oxidant effect was also established in HeLa cells by 2',7'-dichlorodihydrofluorescein diacetate assay.

Effects of memantine on mania-like phenotypes exhibited by Drosophila Shaker mutants.

INTRODUCTION: Increased glutamate levels and electrolytic fluctuations have been observed in acutely manic patients. Despite some efficacy of the non-competitive NMDA receptor antagonist memantine (Mem), such as antidepressant-like and mood-stabilizer drugs in clinical studies, its specific mechanisms of action are still uncertain. The present study aims to better characterize the Drosophila melanogaster fly Shaker mutants (SH), as a translational model of manic episodes within bipolar disorder in humans, and to investigate the potential anti-manic properties of Mem. METHODS AND RESULTS: Our findings showed typical behavioral abnormalities in SH, which mirrored with the overexpression of NMDAR-NR1 protein subunit, matched well to glutamate up-regulation. Such molecular features were associated to a significant reduction of SH brain volume in comparison to Wild Type strain flies (WT). Here we report on the ability of Mem treatment to ameliorate behavioral aberrations of SH (similar to that of Lithium), and its ability to reduce NMDAR-NR1 over-expression. CONCLUSIONS: Our results show the involvement of the glutamatergic system in the SH, given the interaction between the Shaker channel and the NMDA receptor, suggesting this model as a promising tool for studying the neurobiology of bipolar disorders. Moreover, our results show Mem as a potential disease-modifying therapy, providing insight on new mechanisms of action.

Human Neuronal Cell Lines as An In Vitro Toxicological Tool for the Evaluation of Novel Psychoactive Substances.

Novel psychoactive substances (NPS) are synthetic substances belonging to diverse groups, designed to mimic the effects of scheduled drugs, resulting in altered toxicity and potency. Up to now, information available on the pharmacology and toxicology of these new substances is very limited, posing a considerable challenge for prevention and treatment. The present in vitro study investigated the possible mechanisms of toxicity of two emerging NPS (i) 4'-methyl-alpha-pyrrolidinoexanophenone (3,4-MDPHP), a synthetic cathinone, and (ii) 2-chloro-4,5-methylenedioxymethamphetamine (2-Cl-4,5-MDMA), a phenethylamine. In addition, to apply our model to the class of synthetic opioids, we evaluated the toxicity of fentanyl, as a reference compound for this group of frequently abused substances. To this aim, the in vitro toxic effects of these three compounds were evaluated in dopaminergic-differentiated SH-SY5Y cells. Following 24 h of exposure, all compounds induced a loss of viability, and oxidative stress in a concentration-dependent manner. 2-Cl-4,5-MDMA activates apoptotic processes, while 3,4-MDPHP elicits cell death by necrosis. Fentanyl triggers cell death through both mechanisms. Increased expression levels of pro-apoptotic Bax and caspase 3 activity were observed following 2-Cl-4,5-MDMA and fentanyl, but not 3,4-MDPHP exposure, confirming the different modes of cell death.

COR758, a negative allosteric modulator of GABAB receptors.

Allosteric modulators of G protein coupled receptors (GPCRs), including GABABRs (GABABRs), are promising therapeutic candidates. While several positive allosteric modulators (PAM) of GABABRs have been characterized, only recently the first negative allosteric modulator (NAM) has been described. In the present study, we report the characterization of COR758, which acts as GABABR NAM in rat cortical membranes and CHO cells stably expressing GABABRs (CHO-GABAB). COR758 failed to displace the antagonist [3H]CGP54626 from the orthosteric binding site of GABABRs showing that it acts through an allosteric binding site. Docking studies revealed a possible new allosteric binding site for COR758 in the intrahelical pocket of the GABAB1 monomer. COR758 inhibited basal and GABABR-stimulated O-(3-[35Sthio)-triphosphate ([35S]GTPγS) binding in brain membranes and blocked the enhancement of GABABR-stimulated [35S]GTPγS binding by the PAM GS39783. Bioluminescent resonance energy transfer (BRET) measurements in CHO-GABAB cells showed that COR758 inhibited G protein activation by GABA and altered GABABR subunit rearrangements. Additionally, the compound altered GABABR-mediated signaling such as baclofen-induced inhibition of cAMP production in transfected HEK293 cells, agonist-induced Ca2+ mobilization as well as baclofen and the ago-PAM CGP7930 induced phosphorylation of extracellular signal-regulated kinases (ERK1/2) in CHO-GABAB cells. COR758 also prevented baclofen-induced outward currents recorded from rat dopamine neurons, substantiating its property as a NAM for GABABRs. Altogether, these data indicate that COR758 inhibits G protein signaling by GABABRs, likely by interacting with an allosteric binding-site. Therefore, COR758 might serve as a scaffold to develop additional NAMs for therapeutic intervention.

Anti-Aging Potential of Extracts from Washingtonia filifera Seeds.

The aim of this study was to test the inhibitory effect of fruit extracts from Washingtonia filifera on skin aging-related enzymes. The pulp extracts did not exert a significant enzyme inhibition while seed extracts from W. filifera exhibit anti-elastase, anti-collagenase, and anti-tyrosinase activities. Tyrosinase was mildly inhibited while a stronger effect was observed with respect to elastase and collagenase inhibition. Alcoholic extracts provided better results than aqueous extracts. Among them, methanol extracts showed the prominent enzyme inhibitory activities being IC50 value for elastase and collagenase comparable and even better than the reference compound. The inhibition mode of the most active extracts was investigated by Lineweaver-Burk plot analysis. Seed extracts from W. filifera were also investigated for their photo-protective effect by Mansur equation and the antioxidant activity of W. filifera extract was evaluated in oxidative-stressed cells. To evaluate the safety of the extract, the effect on cell viability of human keratinocytes cells was analyzed. Methanol extract presented the best photo-protective effect and exerted an antioxidant activity in a cellular system with no cytotoxic effect. The overall results demonstrate that W. filifera extracts are promising sources of bioactive compounds that could be used in cosmetic and pharmaceutical preparation.

A new biological prospective for the 2-phenylbenzofurans as inhibitors of α-glucosidase and of the islet amyloid polypeptide formation.

In this study, we have investigated a series of hydroxylated 2-phenylbenzofurans compounds for their inhibitory activity against α-amylase and α-glucosidase activity. Inhibitors of carbohydrate degrading enzymes seem to have an important role as antidiabetic drugs. Diabetes mellitus is a wide-spread metabolic disease characterized by elevated levels of blood glucose. The most common is type 2 diabetes, which can lead to severe complications. Since the aggregates of islet amyloid polypeptide (IAPP) are common in diabetic patients, the effect of compounds to inhibit amyloid fibril formation was also determined. All the compounds assayed showed to be more active against α-glucosidase. Compound 16 showed the lowest IC50 value of the series, and it is found to be 167 times more active than acarbose, the reference compound. The enzymatic activity assays showed that compound 16 acts as a mixed-type inhibitor of α-glucosidase. Furthermore, compound 16 displayed effective inhibition of IAPP aggregation and it manifested no significant cytotoxicity. To predict the binding of compound 16 to IAPP and α-glucosidase protein complexes, molecular docking studies were performed. Altogether, our results support that the 2-phenylbenzofuran derivatives could represent a promising candidate for developing molecules able to modulate multiple targets involved in diabetes mellitus disorder.

Telomere attrition and inflammatory load in severe psychiatric disorders and in response to psychotropic medications.

Individuals with severe psychiatric disorders have a reduced life expectancy compared to the general population. At the biological level, patients with these disorders present features that suggest the involvement of accelerated aging, such as increased circulating inflammatory markers and shorter telomere length (TL). To date, the role of the interplay between inflammation and telomere dynamics in the pathophysiology of severe psychiatric disorders has been scarcely investigated. In this study we measured T-lymphocytes TL with quantitative fluorescent in situ hybridization (Q-FISH) and plasma levels of inflammatory markers in a cohort comprised of 40 patients with bipolar disorder (BD), 41 with schizophrenia (SZ), 37 with major depressive disorder (MDD), and 36 non-psychiatric controls (NPC). TL was shorter in SZ and in MDD compared to NPC, while it was longer in BD (model F6, 137 = 20.128, p = 8.73 × 10-17, effect of diagnosis, F3 = 31.870; p = 1.08 × 10-15). There was no effect of the different classes of psychotropic medications, while duration of treatment with mood stabilizers was associated with longer TL (Partial correlation controlled for age and BMI: correlation coefficient = 0.451; p = 0.001). Levels of high-sensitivity C-Reactive Protein (hsCRP) were higher in SZ compared to NPC (adjusted p = 0.027), and inversely correlated with TL in the whole sample (r = -0.180; p = 0.042). Compared to NPC, patients with treatment resistant (TR) SZ had shorter TL (p = 0.001), while patients with TR MDD had higher levels of tumor necrosis factor-α (TNFα) compared to NPC (p = 0.028) and to non-TR (p = 0.039). Comorbidity with cardio-metabolic disorders did not influence the observed differences in TL, hsCRP, and TNFα among the diagnostic groups. Our study suggests that patients with severe psychiatric disorders present reduced TL and increased inflammation.

Differences in telomere length between patients with bipolar disorder and controls are influenced by lithium treatment.

Aim: To assess the role of lithium treatment in the relationship between bipolar disorder (BD) and leukocyte telomere length (LTL). Materials & methods: We compared LTL between 131 patients with BD, with or without a history of lithium treatment, and 336 controls. We tested the association between genetically determined LTL and BD in two large genome-wide association datasets. Results: Patients with BD with a history lithium treatment showed longer LTL compared with never-treated patients (p = 0.015), and similar LTL compared with controls. Patients never treated with lithium showed shorter LTL compared with controls (p = 0.029). Mendelian randomization analysis showed no association between BD and genetically determined LTL. Conclusion: Our data support previous findings showing that long-term lithium treatment might protect against telomere shortening.

A multidisciplinary approach to mental illness: do inflammation, telomere length and microbiota form a loop? A protocol for a cross-sectional study on the complex relationship between inflammation, telomere length, gut microbiota and psychiatric disorders.

INTRODUCTION: Severe psychiatric disorders are typically associated with a significant reduction in life expectancy compared with the general population. Among the different hypotheses formulated to explain this observation, accelerated ageing has been increasingly recognised as the main culprit. At the same time, telomere shortening is becoming widely accepted as a proxy molecular marker of ageing. The present study aims to fill a gap in the literature by better defining the complex interaction/s between inflammation, age-related comorbidities, telomere shortening and gut microbiota in psychiatric disorders. METHODS AND ANALYSIS: A cross-sectional study is proposed, recruiting 40 patients for each of three different diagnostic categories (bipolar disorder, schizophrenia and major depressive disorder) treated at the Section of Psychiatry and at the Unit of Clinical Pharmacology of the University Hospital Agency of Cagliari (Italy), compared with 40 age-matched and sex-matched non-psychiatric controls. Each group includes individuals suffering, or not, from age-related comorbidities, to account for the impact of these medical conditions on the biological make-up of recruited patients. The inflammatory state, microbiota composition and telomere length (TL) are assessed. ETHICS AND DISSEMINATION: The study protocol was approved by the Ethics Committee of the University Hospital Agency of Cagliari (PG/2018/11693, 5 September 2018). The study is conducted in accordance with the principles of good clinical practice and the Declaration of Helsinki, and in compliance with the relevant Italian national legislation. Written, informed consent is obtained from all participants. Participation in the study is on a voluntary basis only. Patients will be part of the dissemination phase of the study results, during which a local conference will be organised and families of patients will also be involved. Moreover, findings will be published in one or more research papers and presented at national and international conferences, in posters or oral communications.

Conjugated Linoleic Acid and Brain Metabolism: A Possible Anti-Neuroinflammatory Role Mediated by PPARα Activation.

Fatty acids play a crucial role in the brain as specific receptor ligands and as precursors of bioactive metabolites. Conjugated linoleic acid (CLA), a group of positional and geometric isomers of linoleic acid (LA, 18:2 n-6) present in meat and dairy products of ruminants and synthesized endogenously in non-ruminants and humans, has been shown to possess different nutritional properties associated with health benefits. Its ability to bind to peroxisome proliferator-activated receptor (PPAR) α, a nuclear receptor key regulator of fatty acid metabolism and inflammatory responses, partly mediates these beneficial effects. CLA is incorporated and metabolized into brain tissue where induces the biosynthesis of endogenous PPARα ligands palmitoylethanolamide (PEA) and oleoylethanolamide (OEA), likely through a positive feedback mechanism where PPARα activation sustains its own cellular effects through ligand biosynthesis. In addition to PPARα, PEA and OEA may as well bind to other receptors such as TRPV1, further extending CLA own anti-neuroinflammatory actions. Future studies are needed to investigate whether dietary CLA may exert anti-inflammatory activity, particularly in the setting of neurodegenerative diseases and neuropsychiatric disorders with a neuroinflammatory basis.

Downregulation of inflammatory markers by conjugated linoleic acid isomers in human cultured astrocytes.

OBJECTIVES: Conjugated linoleic acid (CLA) isomers have been shown to possess anti-inflammatory activity in the central nervous system. In this study, we aimed to evaluate whether modulation of the fatty acid profile by the CLA isomers c9,t11 or t10,c12CLA was associated with changes in the expression of pro-inflammatory molecules in human astrocytes. METHODS: Cultured astrocytes were treated for 6 days with 100 µM fatty acids (c9,t11CLA or t10,c12CLA or oleic acid). Following the treatment, the fatty acid profile of the cell and pro-inflammatory molecule expression were assessed. RESULTS: Only the t10,c12CLA isomer induced a significant decrease in arachidonic acid and increased the ratio of docosahexaenoic acid/eicosapentaenoic acid, which constitutes indirect evidence of peroxisome proliferator-activated receptor alpha activation. Inhibition of tumour necrosis factor-α, interleukin-1ß, and RANTES expression was observed in astrocytes treated with c9,t11CLA and t10,c12CLA. DISCUSSION: Current data demonstrate that CLA isomers, particularly t10,c12, may affect neuroinflammation by reducing the pro-inflammatory molecules in cultured astrocytes, suggesting a potential nutritional role of CLA isomers in modulating the astrocyte inflammatory response.

Coumarin derivatives as promising xanthine oxidase inhibitors.

Xanthine oxidase (XO) is an interesting target for the synergic treatment of several diseases. Coumarin scaffold plays an important role in the design of efficient and potent inhibitors. In the current work, twenty 3-arylcoumarins and eight 3-heteroarylcoumarins were evaluated for their ability to inhibit XO. Among all the candidates, 5,7-dihydroxy-3-(3'-hydroxyphenyl)coumarin (compound 20) proved to be the best inhibitor with an IC50 of 2.13 µM, being 7-fold better than the reference compound, allopurinol (IC50 = 14.75 µM). To deeply understand the potential of this compound, the inhibition mode was also evaluated. Compound 20 showed an uncompetitive profile of inhibition. Molecular docking studies were carried out to analyze the interaction of compound 20 with the studied enzyme. The binding mode involving residues different from the catalytic site of the binding pocket, is compatible to the observed uncompetitive inhibition. Compound 20 was not cytotoxic at its IC50 value, as demonstrated by the viability of 99.1% in 3 T3 cells. Furthermore, pharmacokinetics and physicochemical properties were also calculated, which corroborated with the potential of the studied compounds as promising XO inhibitors.

Mesoporous silica nanoparticles functionalized with hyaluronic acid. Effect of the biopolymer chain length on cell internalization.

Mesoporous silica nanoparticles (MSNs) were functionalized with amino groups (MSN-NH2) and then with hyaluronic acid, a biocompatible biopolymer which can be recognized by CD44 receptors in tumor cells, to obtain a targeting drug delivery system. To this purpose, three hyaluronic acid samples differing for the molecular weight, namely HAS (8-15 kDa), HAM (30-50 kDa) and HAL (90-130 kDa), were used. The MSN-HAS, MSN-HAM, and MSN-HAL materials were characterized through zeta potential and dynamic light scattering measurements at pH = 7.4 and T = 37 °C to simulate physiological conditions. While zeta potential showed an increasing negative value with the increase of the HA chain length, an anomalous value of the hydrodynamic diameter was observed for MSN-HAL, which was smaller than that of MSN-HAS and MSN-HAM samples. The cellular uptake of MSN-HA samples on HeLa cells at 37 °C was studied by optical and electron microscopy. HA chain length affected significantly the cellular uptake that occurred at a higher extent for MSN-NH2 and MSN-HAS than for MSN-HAM and MSN-HAL samples. Cellular uptake experiments carried out at 4 °C showed that the internalization process was inhibited for MSN-HA samples but not for MSN-NH2. This suggests the occurrence of two different mechanisms of internalization. For MSN-NH2 the uptake is mainly driven by the attractive electrostatic interaction with membrane phospholipids, while MSN-HA internalization involves CD44 receptors overexpressed in HeLa cells.

Osmotic behaviour of human mesenchymal stem cells: Implications for cryopreservation.

Aimed at providing a contribution to the optimization of cryopreservation processes, the present work focuses on the osmotic behavior of human mesenchymal stem cells (hMSCs). Once isolated from the umbilical cord blood (UCB) of three different donors, hMSCs were characterized in terms of size distribution and their osmotic properties suitably evaluated through the exposure to hypertonic and isotonic aqueous solutions at three different temperatures. More specifically, inactive cell volume and cell permeability to water and di-methyl sulfoxide (DMSO) were measured, being cell size determined using impedance measurements under both equilibrium and dynamic conditions. Experimental findings indicate that positive cell volume excursions are limited by the apparent increase of inactive volume, which occurs during both the shrink-swell process following DMSO addition and the subsequent restoration of isotonic conditions in the presence of hypertonic solutions of impermeant or permeant solutes. Based on this evidence, hMSCs must be regarded as imperfect osmometers, and their osmotic behavior described within a scenario no longer compatible with the simple two-parameter model usually utilized in the literature. In this respect, the activation of mechano-sensitive ion-channels seemingly represents a reasonable hypothesis for rationalizing the observed osmotic behavior of hMSCs from UCB.