Order vs. Disorder: Cholesterol and Omega-3 Phospholipids Determine Biomembrane Organization

Lipid structural diversity strongly affects biomembrane chemico-physical and structural properties in addition to membrane-associated events. At high concentrations, cholesterol increases membrane order and rigidity, while polyunsaturated lipids are reported to increase disorder and flexibility. How these different tendencies balance in composite bilayers is still controversial. In this study, electron paramagnetic resonance spectroscopy, small angle neutron scattering, and neutron reflectivity were used to investigate the structural properties of cholesterol-containing lipid bilayers in the fluid state with increasing amounts of polyunsaturated omega-3 lipids. Either the hybrid 1-stearoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine or the symmetric 1,2-docosahexaenoyl-sn-glycero-3-phosphocholine were added to the mixture of the naturally abundant 1-palmitoyl-2-oleyl-sn-glycero-3-phosphocholine and cholesterol. Our results indicate that the hybrid and the symmetric omega-3 phospholipids affect the microscopic organization of lipid bilayers differently. Cholesterol does not segregate from polyunsaturated phospholipids and, through interactions with them, is able to suppress the formation of non-lamellar structures induced by the symmetric polyunsaturated lipid. However, this order/disorder balance leads to a bilayer whose structural organization cannot be ascribed to either a liquid ordered or to a canonical liquid disordered phase, in that it displays a very loose packing of the intermediate segments of lipid chains.     

Insights into the Pharmacokinetics and In Vitro Cell-Based Studies of the Imidazoline I2 Receptor Ligand B06

The impact of neurodegenerative diseases (ND) is becoming unbearable for humankind due to their vast prevalence and the lack of efficacious treatments. In this scenario, we focused on imidazoline I₂ receptors (I₂-IR) that are widely distributed in the brain and are altered in patients with brain disorders. We took the challenge of modulating I₂-IR by developing structurally new molecules, in particular, a family of bicyclic α-iminophosphonates, endowed with high affinity and selectivity to these receptors. Treatment of two murine models, one for age-related cognitive decline and the other for Alzheimer’s disease (AD), with representative compound B06 ameliorated their cognitive impairment and improved their behavioural condition. Furthermore, B06 revealed beneficial in vitro ADME-Tox properties. The pharmacokinetics (PK) and metabolic profile are reported to de-risk B06 for progressing in the preclinical development. To further characterize the pharmacological properties of B06, we assessed its neuroprotective properties and beneficial effect in an in vitro model of Parkinson’s disease (PD). B06 rescued the human dopaminergic cell line SH-SY5Y from death after treatment with 6-hydroxydopamine (6-OHDA) and showed a crucial anti-inflammatory effect in a cellular model of neuroinflammation. This research reveals B06 as a putative candidate for advancing in the difficult path of drug discovery and supports the modulation of I₂-IR as a fresh approach for the therapy of ND.     

Role of miRNAs in Human T Cell Leukemia Virus Type 1 Induced T Cell Leukemia: A Literature Review and Bioinformatics Approach

Human T cell leukemia virus type 1 (HTLV-1) was identified as the first pathogenic human retrovirus and is estimated to infect 5 to 10 million individuals worldwide. Unlike other retroviruses, there is no effective therapy to prevent the onset of the most alarming diseases caused by HTLV-1, and the more severe cases manifest as the malignant phenotype of adult T cell leukemia (ATL). MicroRNA (miRNA) dysfunction is a common feature of leukemogenesis, and it is no different in ATL cases. Therefore, we sought to analyze studies that reported deregulated miRNA expression in HTLV-1 infected cells and patients’ samples to understand how this deregulation could induce malignancy. Through in silico analysis, we identified 12 miRNAs that stood out in the prediction of targets, and we performed functional annotation of the genes linked to these 12 miRNAs that appeared to have a major biological interaction. A total of 90 genes were enriched in 14 KEGG pathways with significant values, including TP53, WNT, MAPK, TGF-β, and Ras signaling pathways. These miRNAs and gene interactions are discussed in further detail for elucidation of how they may act as probable drivers for ATL onset, and while our data provide solid starting points for comprehension of miRNAs’ roles in HTLV-1 infection, continuous effort in oncologic research is still needed to improve our understanding of HTLV-1 induced leukemia.     

Galectin 1—A Key Player between Tissue Repair and Fibrosis

Galectins are ten family members of carbohydrate-binding proteins with a high affinity for β galactose-containing oligosaccharides. Galectin-1 (Gal-1) is the first protein discovered in the family, expressed in many sites under normal and pathological conditions. In the first part of the review article, we described recent advances in the Gal-1 modulatory role on wound healing, by focusing on the different phases triggered by Gal-1, such as inflammation, proliferation, tissue repair and re-epithelialization. On the contrary, Gal-1 persistent over-expression enhances angiogenesis and extracellular matrix (ECM) production via PI3K/Akt pathway activation and leads to keloid tissue. Therefore, the targeted Gal-1 modulation should be considered a method of choice to treat wound healing and avoid keloid formation. In the second part of the review article, we discuss studies clarifying the role of Gal-1 in the pathogenesis of proliferative diabetic retinopathy, liver, renal, pancreatic and pulmonary fibrosis. This evidence suggests that Gal-1 may become a biomarker for the diagnosis and prognosis of tissue fibrosis and a promising molecular target for the development of new and original therapeutic tools to treat fibrosis in different chronic diseases.     

First Report on Genome Editing via Ribonucleoprotein (RNP) in Castanea sativa Mill.

Castanea sativa is an important tree nut species worldwide, highly appreciated for its multifunctional role, in particular for timber and nut production. Nowadays, new strategies are needed to achieve plant resilience to diseases, climate change, higher yields, and nutritional quality. Among the new plant breeding techniques (NPBTs), the CRISPR/Cas9 system represents a powerful tool to improve plant breeding in a short time and inexpensive way. In addition, the CRISPR/Cas9 construct can be delivered into the cells in the form of ribonucleoproteins (RNPs), avoiding the integration of exogenous DNA (GMO-free) through protoplast technology that represents an interesting material for gene editing thanks to the highly permeable membrane to DNA. In the present study, we developed the first protoplast isolation protocol starting from European chestnut somatic embryos. The enzyme solution optimized for cell wall digestion contained 1% cellulase Onozuka R-10 and 0.5% macerozyme R-10. After incubation for 4 h at 25 °C in dark conditions, a yield of 4,500,000 protoplasts/mL was obtained (91% viable). The transfection capacity was evaluated using the GFP marker gene, and the percentage of transfected protoplasts was 51%, 72 h after the transfection event. The direct delivery of the purified RNP was then performed targeting the phytoene desaturase gene. Results revealed the expected target modification by the CRISPR/Cas9 RNP and the efficient protoplast editing.     

First-Void Urine Microbiome in Women with Chlamydia trachomatis Infection

Background: Chlamydia trachomatis (CT) is the agent of the most common bacterial sexually transmitted infection worldwide. Until now, little information is available about the microbial composition of urine samples during CT urethritis. Therefore, in this study, we characterized the microbiome and metabolome profiles of first-void urines in a cohort of women with CT urethral infection attending an STI clinic. Methods: Based on CT positivity by nucleic acid amplification techniques on urine samples, the enrolled women were divided into two groups, i.e., “CT-negative” (n = 21) and “CT-positive” (n = 11). Urine samples were employed for (i) the microbiome profile analysis by means of 16s rRNA gene sequencing and (ii) the metabolome analysis by ¹H-NMR. Results: Irrespective of CT infection, the microbiome of first-void urines was mainly dominated by Lactobacillus, L. iners and L. crispatus being the most represented species. CT-positive samples were characterized by reduced microbial biodiversity compared to the controls. Moreover, a significant reduction of the Mycoplasmataceae family—in particular, of the Ureaplasma parvum species—was observed during CT infection. The Chlamydia genus was positively correlated with urine hippurate and lactulose. Conclusions: These data can help elucidate the pathogenesis of chlamydial urogenital infections, as well as to set up innovative diagnostic and therapeutic approaches.     

Platelet-Derived miR-126-3p Directly Targets AKT2 and Exerts Anti-Tumor Effects in Breast Cancer Cells: Further Insights in Platelet-Cancer Interplay

Among the surrounding cells influencing tumor biology, platelets are recognized as novel players as they release microvesicles (MVs) that, once delivered to cancer cells, modulate signaling pathways related to cell growth and dissemination. We have previously shown that physiological delivery of platelet MVs enriched in miR-126 exerted anti-tumor effects in different breast cancer (BC) cell lines. Here, we seek further insight by identifying AKT2 kinase as a novel miR-126-3p direct target, as assessed by bioinformatic analysis and validated by luciferase assay. Both ectopic expression and platelet MV-mediated delivery of miR-126-3p downregulated AKT2 expression, thus suppressing proliferating and invading properties, in either triple negative (BT549 cells) or less aggressive Luminal A (MCF-7 cells) BC subtypes. Accordingly, as shown by bioinformatic analysis, both high miR-126 and low AKT2 levels were associated with favorable long-term prognosis in BC patients. Our results, together with the literature data, indicate that miR-126-3p exerts suppressor activity by specifically targeting components of the PIK3/AKT signaling cascade. Therefore, management of platelet-derived MV production and selective delivery of miR-126-3p to tumor cells may represent a useful tool in multimodal therapeutic approaches in BC patients.     

Can porous polymeric scaffolds be functionalized by stem cells leading to osteogenic differentiation? A systematic review of in vitro studies

The aim of this study was to analyze the influence of nanoporous structure of polymeric biomaterials on the in vitro osteogenic induction of human stem cells. An electronic search in three databases (MEDLINE, SCOPUS, and Web of Science) was performed for articles that were published before May 2018. In vitro studies were included if they met the following criteria: (1) the use of polymeric scaffolds (natural or synthetic); (2) the co-culture of human stem cells with the scaffold; and (3) cell viability, proliferation, and osteogenic differentiation assays. The main characteristics of the published studies were summarized, and a quality assessment tool was used to analyze methodological features. Eighty-eight potential articles were firstly retrieved. Thirteen were eligible for qualitative analysis. Only three studies characterized cell stemness. Nanostructure of the scaffolds showed a significant influence on viability, proliferation, and osteogenic differentiation of human stem cells. Combination of porosity between 72 and 93% and a large range diameter between 50 and 224 μm resulted in more remarkable cellular proliferation and differentiation. Porous polymeric scaffolds can be functionalized by stem cells leading to osteogenic induction. High standards of laboratory practice and accurate methodological reporting are essential for the credibility of the results.     

ILB®, a Low Molecular Weight Dextran Sulphate,Restores Glutamate Homeostasis,Amino Acid Metabolism and Neurocognitive Functions in a Rat Model of Severe Traumatic Brain Injury

In a previous study, we found that administration of ILB^®, a new low molecular weight dextran sulphate, significantly improved mitochondrial functions and energy metabolism, as well as decreased oxidative/nitrosative stress, of brain tissue of rats exposed to severe traumatic brain injury (sTBI), induced by the closed-head weight-drop model of diffused TBI. Using aliquots of deproteinized brain tissue of the same animals of this former study, we here determined the concentrations of 24 amino acids of control rats, untreated sTBI rats (sacrificed at 2 and 7 days post-injury) and sTBI rats receiving a subcutaneous ILB^® administration (at the dose levels of 1, 5 and 15 mg/kg b.w.) 30 min post-impact (sacrificed at 2 and 7 days post-injury). Additionally, in a different set of experiments, new groups of control rats, untreated sTBI rats and ILB^®-treated rats (administered 30 min after sTBI at the dose levels of 1 or 5 mg/kg b.w.) were studied for their neurocognitive functions (anxiety, locomotor capacities, short- and long-term memory) at 7 days after the induction of sTBI. Compared to untreated sTBI animals, ILB^® significantly decreased whole brain glutamate (normalizing the glutamate/glutamine ratio), glycine, serine and γ-aminobutyric acid. Furthermore, ILB^® administration restored arginine metabolism (preventing nitrosative stress), levels of amino acids involved in methylation reactions (methionine, L-cystathionine, S-adenosylhomocysteine), and N-acetylaspartate homeostasis. The macroscopic evidences of the beneficial effects on brain metabolism induced by ILB^® were the relevant improvement in neurocognitive functions of the group of animals treated with ILB^® 5 mg/kg b.w., compared to the marked cognitive decline measured in untreated sTBI animals. These results demonstrate that ILB^® administration 30 min after sTBI prevents glutamate excitotoxicity and normalizes levels of amino acids involved in crucial brain metabolic functions. The ameliorations of amino acid metabolism, mitochondrial functions and energy metabolism in ILB^®-treated rats exposed to sTBI produced significant improvement in neurocognitive functions, reinforcing the concept that ILB^® is a new effective therapeutic tool for the treatment of sTBI, worth being tested in the clinical setting.