Molecular dynamics simulations of quinine encapsulation into biodegradable nanoparticles: A possible new strategy against Sars-CoV-2

A new coronavirus disease, SARS-CoV-2, has spread into a global pandemic in December 2019. Since no specific therapeutic drugs for treating COVID-19 have been approved by FDA, recent studies suggest that the known antimalarial quinine and its derivatives (chloroquine and hydroxychloroquine) inhibit receptor binding of the viral particles and inhibits the strong “cytokine storm”, which is the main cause of death among infected patients. In particular, the natural alkaloid quinine has shown to possess a better safety profile and greater tolerability compared to its derivatives. Dosage optimization of quinine is still necessary as the currently available dosage forms have controversial pharmacokinetics and safety profiles. Therefore, repurposing quinine dosage forms to improve its pharmacokinetics and safety profile may be necessary to support its use against SARS-CoV-2. In this context, biodegradable/biocompatible polymeric nanoparticles may provide a safe site-specific and controlled quinine delivery, reducing the frequency of drug administration and the dose. In this study, a full atomistic molecular dynamics simulation approach has been used to investigate the use of poly-(glycolic acid) and poly-(lactic acid) and their copolymer poly-(lactic-co-glycolic acid) as potential delivery systems for lipophilic quinine to get insights into the mechanism of quinine encapsulation and release at the atomic/molecular level

E- CONVEX FUNCTIONS

Youness introduced the concepts of E – convex sets and E – convex functions and studied their properties. Following this in this paper we further characterize E- convex functions. AMS Subject Cllasification(2000)Nos: 26A51,26B25,32F,32T,46A03,46A55,52A

Fractal lacunarity of trabecular bone in vertebral MRI to predict osteoporotic fracture risk in over-fifties women. The LOTO study

Background. Osteoporotic fractures are a major cause of morbidity in the elderly. Menopausal women represent the population with the highest risk of early osteoporosis onset, often accompanied by vertebral fractures (VF). Bone mineral density (BMD) is commonly assessed by dual-energy X-ray absorptiometry (DXA) for osteoporosis diagnosis; however, BMD alone does not represent a significant predictor of fracture risk. Bone microarchitecture, instead, arises as a determinant of bone fragility independent of BMD. High-resolution magnetic resonance imaging (MRI) is an effective noninvasive/nonionizing tool for in vivo characterisation of trabecular bone microarchitecture (TBA). We have previously set up an MRI method able to characterise TBA changes in aging and osteoporosis by one parameter, trabecular bone lacunarity parameter beta (TBL beta). Fractal lacunarity was used for TBA texture analysis as it describes discontinuity of bone network and size of bone marrow spaces, changes of which increase the risk of bone fracture. This study aims to assess the potential of TBL beta method as a tool for osteoporotic fracture risk. Methods. An observational, cross-sectional, and prospective study on over-50s women at risk for VF was designed. TBL beta, our index of osteoporotic fracture risk, is the main outcome measure. It was calculated on lumbar vertebra axial images, acquired by 1.5T MRI spin-echo technique, from 279 osteopenic/osteoporotic women with/without prior VF. Diagnostic power of TBL beta method, by Receiver Operating Characteristics (ROC) curve and other diagnostic accuracy measurements were compared with lumbar spine DXA-BMD. Results. Baseline results show that TBL beta is able to discriminate patients with/without prevalent VF (p=0.003). AUC (area under the curve from ROC) is 0.63 for TBL beta, statistically higher (p=0.012) than BMD one (0.53). Contribution of TBL beta to prevalent VF is statistically higher (p<0.001) than BMD (sensitivity: 66% vs. 52% respectively; OR: 3.20, p<0.0001 for TBL beta vs. 1.31, p=0.297 for BMD). Preliminary 1-year prospective results suggest that TBA contribution to incident VF is even higher (sensitivity: 73% for TBL beta vs. 55% for BMD; RR: 3.00, p=0.002 for TBL beta vs. 1.31, p=0.380 for BMD). Conclusion. Results from this study further highlight the usefulness of TBL beta as a biomarker of TBA degeneration and an index of osteoporotic fracture risk

Depth Distribution of Spin-Labeled Liponitroxides within Lipid Bilayers: A Combined EPR and Molecular Dynamics Approach

The distribution in an egg\u2013phosphatidylcholine bilayer of a series of spin-labeled nitroxides, potentially useful as targeted antioxidants, has been investigated using molecular dynamics (MD) simulations. The in silico method has been tested at first for a series of n-doxyl-phosphocholine-doped bilayers, with the doxyl moiety located at different positions (n) of the lipid chain, in analogy to electron paramagnetic resonance (EPR) spin labeling and other MD studies. As a result, a novel calibration curve has been obtained, suitable to determine the absolute membrane penetration depth of any paramagnetic solute from EPR measurements. A second series of MD simulations was then carried out on the newly synthesized series of liponitroxides (NOXs) recently tested as antioxidants against the lipid peroxidation of polyunsaturated fatty acids in membranes: their penetration depths, as determined by EPR in phosphatidylcholine liposomes, were correlated with their antioxidant efficacy. In these NOXs, a glycerol moiety is esterified with a carboxy derivative of a pyrroline nitroxide and one or two oleic acid residues. A very good agreement between the EPR experimental results and those from the current MD simulations indicates that the short distance of the nitroxide moiety from the fatty acid double bonds has been now definitively assessed; moreover, it indicates that our MD methodology could be successfully employed in the absence of nonparamagnetic species

Differential course of HIV-1 infection and apolipoprotein E polymorphism

Abstract We studied the course of infection with human immunodeficiency virus type 1 (HIV-1) in relation to apolipoprotein E (APOE) polymorphism found for 209 Italians treated at Infectious Disease Clinics in Rome and Modena. Clinically, patients were classified into four groups according to the yearly rate of decline in CD4+ cell count (LTNP: long-term non-progression; SLOW, 'NORMAL' or RAPID). Patients at both extremes of the clinical spectrum, i.e. those who rapidly progressed to AIDS and those with stable high CD4 cell counts, had few APOE ɛ4 and ɛ2 alleles (P = 0.04). Detailed clinical information was then used to construct four model-based clinical profiles using grade-of-membership analysis (GoM), predictive of APOE genotypic frequencies: 1. The clinical profile associated with good long-term prognosis lacked ɛ2 (P=0.01); 2. Disease progression to AIDS was associated with ɛ4 and ɛ2, most evident for zidovudine-lamivudine regimens without a protease inhibitor (P = 0.03); and, 3. AIDS patients had low ɛ4 and ɛ2 frequencies, consistent with a high mortality rate among ɛ4+ and ɛ2+ AIDS patients. These findings suggest allele-specific immunomodulatory effects involving inherited APOE isoform important enough to alter the clinical course of HIV infection and, possibly, drug efficacy. They imply a connection between lipid metabolism and immunity potentially relevant to common disorders

Adsorption of Polylactic-co-Glycolic Acid on Zinc Oxide Systems: A Computational Approach to Describe Surface Phenomena

Zinc oxide and polylactic-co-glycolic acid (ZnO-PLGA) nanocomposites are known to exhibit different biomedical applications and antibacterial activity, which could be beneficial for adding to wound dressings after different surgeries. However, possible cytotoxic effects along with various unexpected activities could reduce the use of these prominent systems. This is correlated to the property of ZnO, which exhibits different polymeric forms, in particular, wurtzite, zinc-blende, and rocksalt. In this study, we propose a computational approach based on the density functional theory to investigate the properties of ZnO-PLGA systems in detail. First, three different stable polymorphs of ZnO were considered. Subsequently, the abilities of each system to absorb the PLGA copolymer were thoroughly investigated, taking into account the modulation of electrical, optical, and mechanical properties. Significant differences between ZnO and PLGA systems have been found; in this study, we remark on the potential use of these models and the necessity to describe crucial surface aspects that might be challenging to observe with experimental approaches but which can modulate the performance of nanocomposites

Structural Basis for Agonistic Activity and Selectivity toward Melatonin Receptors hMT1 and hMT2

: Glaucoma, a major ocular neuropathy originating from a progressive degeneration of retinal ganglion cells, is often associated with increased intraocular pressure (IOP). Daily IOP fluctuations are physiologically influenced by the antioxidant and signaling activities of melatonin. This endogenous modulator has limited employment in treating altered IOP disorders due to its low stability and bioavailability. The search for low-toxic compounds as potential melatonin agonists with higher stability and bioavailability than melatonin itself could start only from knowing the molecular basis of melatonergic activity. Thus, using a computational approach, we studied the melatonin binding toward its natural macromolecular targets, namely melatonin receptors 1 (MT1) and 2 (MT2), both involved in IOP signaling regulation. Besides, agomelatine, a melatonin-derivative agonist and, at the same time, an atypical antidepressant, was also included in the study due to its powerful IOP-lowering effects. For both ligands, we evaluated both stability and ligand positioning inside the orthosteric site of MTs, mapping the main molecular interactions responsible for receptor activation. Affinity values in terms of free binding energy (ΔGbind) were calculated for the selected poses of the chosen compounds after stabilization through a dynamic molecular docking protocol. The results were compared with experimental in vivo effects, showing a higher potency and more durable effect for agomelatine with respect to melatonin, which could be ascribed both to its higher affinity for hMT2 and to its additional activity as an antagonist for the serotonin receptor 5-HT2c, in agreement with the in silico results

The Association between Single Nucleotide Polymorphisms, including miR-499a Genetic Variants, and Dyslipidemia in Subjects Treated with Pharmacological or Phytochemical Lipid-Lowering Agents

none12noDisorders of lipoprotein metabolism are among the major risk factors for cardiovascular disease (CVD) development. Single nucleotide polymorphisms (SNPs) have been associated with the individual variability in blood lipid profile and response to lipid-lowering treatments. Here, we genotyped 34 selected SNPs located in coding genes related to lipid metabolism, inflammation, coagulation, and a polymorphism in the MIR499 gene-a microRNA previously linked to CVD-to evaluate the association with lipid trait in subjects with moderate dyslipidemia not on lipid-lowering treatment (Treatment-naïve (TN) cohort, n = 125) and in patients treated with statins (STAT cohort, n = 302). We also explored the association between SNPs and the effect of a novel phytochemical lipid-lowering treatment in the TN cohort. We found that 6 SNPs (in the MIR499, TNFA, CETP, SOD2, and VEGFA genes) were associated with lipid traits in the TN cohort, while no association was found with the response to twelve-week phytochemical treatment. In the STAT cohort, nine SNPs (in the MIR499, CETP, CYP2C9, IL6, ABCC2, PON1, IL10, and VEGFA genes) were associated with lipid traits, three of which were in common with the TN cohort. Interestingly, in both cohorts, the presence of the rs3746444 MIR499 SNP was associated with a more favorable blood lipid profile. Our findings could add information to better understand the individual genetic variability in maintaining a low atherogenic lipid profile and the response to different lipid-lowering therapies.openGiuliani, Angelica; Montesanto, Alberto; Matacchione, Giulia; Graciotti, Laura; Ramini, Deborah; Protic, Olga; Galeazzi, Roberta; Antonicelli, Roberto; Tortato, Elena; Bonfigli, Anna Rita; Sabbatinelli, Jacopo; Olivieri, FabiolaGiuliani, Angelica; Montesanto, Alberto; Matacchione, Giulia; Graciotti, Laura; Ramini, Deborah; Protic, Olga; Galeazzi, Roberta; Antonicelli, Roberto; Tortato, Elena; Bonfigli, Anna Rita; Sabbatinelli, Jacopo; Olivieri, Fabiol

Randomized, Double-Blind, Placebo-Controlled Trial to Test the Effects of a Nutraceutical Combination Monacolin K-Free on the Lipid and Inflammatory Profile of Subjects with Hypercholesterolemia

Background: Nutraceutical combinations (NCs) against hypercholesterolemia are increasing in the marketplace. However, the availability of NCs without monacolin K is scarce even though the statin-intolerant population needs it. Methods: This study is a parallel-group, randomized, placebo-controlled, double-blind trial. We evaluated the effects of the NC containing phytosterols, bergamot, olive fruits, and vitamin K2 on lipid profile and inflammatory biomarkers in 118 subjects (mean age ± SD, 57.9 ± 8.8 years; 49 men and 69 women) with hypercholesterolemia (mean total cholesterol ± SD, 227.4 ± 20.8 mg/dL) without clinical history of cardiovascular diseases. At baseline and 6 and 12 weeks of treatment, we evaluated lipid profile (total, LDL and HDL cholesterol, and triglycerides), safety (liver, kidney, and muscle parameters), and inflammatory biomarkers such as hs-CRP, leukocytes, interleukin-32, and interleukin-38 and inflammatory-microRNAs (miRs) miR-21, miR-126, and miR-146a. Results: Compared to the placebo, at 6 and 12 weeks, NC did not significantly reduce total cholesterol (p = 0.083), LDL cholesterol (p = 0.150), and triglycerides (p = 0.822). No changes were found in hs-CRP (p = 0.179), interleukin-32 (p = 0.587), interleukin-38 (p = 0.930), miR-21 (p = 0.275), miR-126 (p = 0.718), miR-146a (p = 0.206), myoglobin (p = 0.164), and creatine kinase (p = 0.376). Among the two reported, only one adverse event was probably related to the nutraceutical treatment. Conclusions: The evaluated nutraceutical combination did not change serum lipid profile and inflammatory parameters, at least not with the daily dose applied in the present study