Extra-virgin olive oil diet and mild physical activity prevent cartilage degeneration in an osteoarthritis model: an in vivo and in vitro study on lubricin expression

Mediterranean diet includes a relatively high fat consumption mostly from monounsaturated fatty acids mainly provided by olive oil, the principal source of culinary and dressing fat. The beneficial effects of olive oil have been widely studied and could be due to its phytochemicals, which have been shown to possess anti-inflammatory properties. Lubricin is a chondroprotective glycoprotein and it serves as a critical boundary lubricant between opposing cartilage surfaces. A joint injury causes an initial flare of cytokines, which decreases lubricin expression and predisposes to cartilage degeneration such as osteoarthritis. The aim of this study was to evaluate the role of extra-virgin olive oil diet and physical activity on inflammation and expression of lubricin in articular cartilage of rats after injury. In this study we used histomorphometric, histological, immunocytochemical, immunohistochemical, western blot and biochemical analysis for lubricin and interleukin-1 evaluations in the cartilage and in the synovial fluid. We report the beneficial effect of physical activity (treadmill training) and extra-virgin olive oil supplementation, on the articular cartilage. The effects of anterior cruciate ligament transection decrease drastically the expression of lubricin and increase the expression of interleukin-1 in rats, while after physical activity and extra-virgin olive oil supplemented diet, the values return to a normal level compared to the control group. With our results we can confirm the importance of the physical activity in conjunction with extra-virgin olive oil diet in medical therapy to prevent osteoarthritis disease in order to preserve the articular cartilage and then the entire joint.     

Subordinate plant species impact on soil microbial communities and ecosystem functioning in grasslands: Findings from a removal experiment

Despite their low relative abundance, subordinate plant species may have larger impacts on ecosystem functioning than expected, but their role in plant communities remains poorly understood. The aim of this study was to test how subordinate plant species influence the functioning of a species-rich semi-natural grasslands. A plant removal experiment was set-up in the mountain grasslands of the Jura Mountains (Switzerland) to test the impact of subordinate plant species on soil microbial communities and ecosystem functioning. The experiment included three treatments: removal of all subordinate species, partial biomass removal of dominant species, and a no biomass removal control. After 2 years of treatments, we determined soil microbial community (bacteria and mycorrhizal fungi) by T-RFLP analysis and measured litter decomposition, soil respiration, soil inorganic nitrogen (DIN) availability and throughout above-ground biomass production as measures of ecosystem function. The removal of subordinate plant species strongly affected bacterial and weakly influenced mycorrhizal fungi communities and decreased rates of plant litter decomposition, soil respiration and DIN availability with larger effects than the partial loss of dominant biomass. The removal of subordinate plant species did not modify plant community structure, but it did reduce total above-ground biomass production compared to the control plots. Collectively, our findings indicate that the loss of subordinate species can have significant consequences for soil microbial communities and ecosystem functions, suggesting that subordinate species are important drivers of ecosystem properties.     

Maternal Antiretroviral Therapy for the Prevention of Mother-To-Child Transmission of HIV in Malawi: Maternal and Infant Outcomes Two Years after Delivery

Background

Optimized preventive strategies are needed to reach the objective of eliminating pediatric AIDS. This study aimed to define the determinants of residual HIV transmission in the context of maternal antiretroviral therapy (ART) administration to pregnant women, to assess infant safety of this strategy, and to evaluate its impact on maternal disease.

Methodology/Principal Findings

A total of 311 HIV-infected pregnant women were enrolled in Malawi in an observational study and received a nevirapine-based regimen from week 25 of gestation until 6 months after delivery (end of breastfeeding period) if their CD4+ count was > 350/mm³ at baseline (n = 147), or indefinitely if they met the criteria for treatment (n. 164). Mother/child pairs were followed until 2 years after delivery. The Kaplan-Meier method was used to estimate HIV transmission, maternal disease progression, and survival at 24 months. The rate of HIV infant infection was 3.2% [95% confidence intervals (CI) 1.0-5.4]. Six of the 8 transmissions occurred among mothers with baseline CD4+ count > 350/mm³. HIV-free survival of children was 85.8% (95% CI 81.4-90.1). Children born to mothers with baseline CD4+ count < 350/mm³ were at increased risk of death (hazard ratio 2.6, 95% CI 1.1-6.1). Among women who had stopped treatment the risk of progression to CD4+ count < 350/mm³ was 20.6% (95% CI 9.2-31.9) by 18 months of drug discontinuation.

Conclusions

HIV transmission in this cohort was rare however, it occurred in a significative proportion among women with high CD4+ counts. Strategies to improve treatment adherence should be implemented to further reduce HIV transmission. Mortality in the uninfected exposed children was the major determinant of HIV-free survival and was associated to maternal disease stage. Given the considerable proportion of women reaching the criteria for treatment within 18 months of drug discontinuation, life-long ART administration to HIV-infected women should be considered.     

Identification of the SPG15 gene, encoding spastizin, as a frequent cause of complicated autosomal-recessive spastic paraplegia, including Kjellin syndrome

Hereditary spastic paraplegias (HSPs) are genetically and phenotypically heterogeneous disorders. Both "uncomplicated" and "complicated" forms have been described with various modes of inheritance. Sixteen loci for autosomal-recessive "complicated" HSP have been mapped. The SPG15 locus was first reported to account for a rare form of spastic paraplegia variably associated with mental impairment, pigmented maculopathy, dysarthria, cerebellar signs, and distal amyotrophy, sometimes designated as Kjellin syndrome. Here, we report the refinement of SPG15 to a 2.64 Mb genetic interval on chromosome 14q23.3-q24.2 and the identification of ZFYVE26, which encodes a zinc-finger protein with a FYVE domain that we named spastizin, as the cause of SPG15. Six different truncating mutations were found to segregate with the disease in eight families with a phenotype that included variable clinical features of Kjellin syndrome. ZFYVE26 mRNA was widely distributed in human tissues, as well as in rat embryos, suggesting a possible role of this gene during embryonic development. In the adult rodent brain, its expression profile closely resembled that of SPG11, another gene responsible for complicated HSP. In cultured cells, spastizin colocalized partially with markers of endoplasmic reticulum and endosomes, suggesting a role in intracellular trafficking.     

Synthesis, structure-activity relationships and molecular modeling studies of new indole inhibitors of monoamine oxidases A and B

New monoamine oxidase inhibitors were synthesized as indole analogues of a previously reported pyrrole series. Several compounds were potent MAO-A (12, 17, 19-22, 31, 36, and 37) or MAO-B (14, 20, 24, 38, 44, and 46) inhibitors, and had K(i) values in the nanomolar concentration range. In particular, 22 (K(i)=0.00092 microM, and SI=68,478) was exceptionally potent and selective as MAO-A inhibitor. In molecular modeling studies, compounds 22, 24, 44, and 46 positioned the indole ring into an aromatic cavity of MAO-A, and established pi-pi stacking interactions with Tyr407, Tyr444, and FAD cofactor. However, only compound 22 was able to form hydrogen bonds with FAD, a finding which was in accordance with its potent anti-MAO-A activity. Conversely, 22/MAOB complex was highly unstable during the MD simulation.     

Prolin-rich tyrosine kinase 2 (PYK2) expression and localization in mouse testis

Prolin-rich kinase 2 (PYK2) is a nonreceptor tyrosine kinase related to the focal adhesion kinase (FAK) p125(FAK). PYK2 is rapidly phosphorylated on tyrosine residues in response to various stimuli, such as tumor necrosis factor-alpha (TNF-alpha), changes in osmolarity, elevation in intracellular calcium concentration, angiotensin, and UV irradiation. PYK2 has ligand sequences for Src homology 2 and 3 (SH-2 and SH-3), and has binding sites for paxillin and p130(cas). Activation of PYK2 leads to modulation of ion channel function, phosphorylation of tyrosine residues, and activation of the MAP kinase signaling pathways. Immunocytochemistry shows that PYK2 is present in mouse germinal and Sertoli cells (ser). Northern blot and immunoprecipitation analysis demonstrate that, among germinal cells, PYK2 is more abundant in spermatocytes (spc) and spermatids (spt); in addition, immunofluorescence analysis clearly shows that the diffuse cytoplasmic localization of PYK2 changes in a specific cellular compartment in spt and spermatozoa.     

Abortive and Propagating Intracellular Calcium Waves: Analysis from a Hybrid Model

The functional properties of inositol(1,4,5)-triphosphate (IP₃) receptors allow a variety of intracellular Ca²⁺ phenomena. In this way, global phenomena, such as propagating and abortive Ca²⁺ waves, as well as local events such as puffs, have been observed. Several experimental studies suggest that many features of global phenomena (e.g., frequency, amplitude, speed wave) depend on the interplay of biophysical processes such as diffusion, buffering, efflux and influx rates, which in turn depend on parameters such as buffer concentration, Ca²⁺ pump density, cytosolic IP₃ level, and intercluster distance. Besides, it is known that cells are able to modify some of these parameters in order to regulate the Ca²⁺ signaling. By using a hybrid model, we analyzed different features of the hierarchy of calcium events as a function of two relevant parameters for the calcium signaling, the intercluster distance and the pump strength or intensity. In the space spanned by these two parameters, we found two modes of calcium dynamics, one dominated by abortive calcium waves and the other by propagating waves. Smaller distances between the release sites promote propagating calcium waves, while the increase of the efflux rate makes the transition from propagating to abortive waves occur at lower values of intercluster distance. We determined the frontier between these two modes, in the parameter space defined by the intercluster distance and the pump strength. Furthermore, we found that the velocity of simulated calcium waves accomplishes Luther’s law, and that an effective rate constant for autocatalytic calcium production decays linearly with both the intercluster distance and the pump strength.     

How pregnancy can affect autoimmune diseases progression?

Autoimmune disorders are characterized by tissue damage, caused by self-reactivity of different effectors mechanisms of the immune system, namely antibodies and T cells. Their occurrence may be associated with genetic and/or environmental predisposition and to some extent, have implications for fertility and obstetrics. The relationship between autoimmunity and reproduction is bidirectional. This review only addresses the impact of pregnancy on autoimmune diseases and not the influence of autoimmunity on pregnancy development. Th17/Th1-type cells are aggressive and pathogenic in many autoimmune disorders and inflammatory diseases. The immunology of pregnancy underlies the role of Th2-type cytokines to maintain the tolerance of the mother towards the fetal semi-allograft. Non-specific factors, including hormonal changes, favor a switch to Th2-type cytokine profile. In pregnancy Th2, Th17/Th2 and Treg cells accumulate in the decidua but may also be present in the mother’s circulation and can regulate autoimmune responses influencing the progression of autoimmune diseases.     

Novel sulfenamides and sulfonamides based on pyridazinone and pyridazine scaffolds as CB1 receptor ligand antagonists

A series of sulfenamide and sulfonamide derivatives was synthesized and evaluated for the affinity at CB₁ and CB₂ receptors. The N-bornyl-S-(5,6-di-p-tolylpyridazin-3-yl)-sulfenamide, compound 11, displayed good affinity and high selectivity for CB₁ receptors (K_i values of 44.6?nM for CB₁ receptors and >40?μM for CB₂ receptors, respectively). The N-isopinocampheyl-sulfenamide 12 and its sulfonamide analogue 22 showed similar selectivity for CB₁ receptors with K_i values of 75.5 and 73.2?nM, respectively. These novel compounds behave as antagonists/inverse agonists at CB₁ receptor in the [³⁵S]-GTPγS binding assays, and none showed adequate predictive blood–brain barrier permeation, exhibiting low estimated LD₅₀. However, testing compound 12 in a supraspinal analgesic test (hot-plate) revealed that it was as effective as the classic CB₁ receptor antagonist rimonabant, in reversing the analgesic effect of a cannabinoid agonist.     

Chondroitin-4-sulphate reduced oxidative injury in caerulein-induced pancreatitis in mice: the involvement of NF-kappaB translocation and apoptosis activation

Activation of nuclear factor kappaB (NF-kappaB) and caspases may greatly amplify inflammation and cell damage in addition to that directly exerted by free radicals. Since reactive oxygen species (ROS) are involved in acute pancreatitis, we studied whether the administration of chondroitin-4-sulphate (C4S), in addition to its antioxidant activity, was able to modulate NF-kappaB and caspase activation in an experimental model of caerulein-induced acute pancreatitis in mice. Hyperstimulating doses of caerulein (50 microg/ kg), five injections per mouse given at hourly intervals produced the following: high serum lipase and amylase activity; lipid peroxidation, evaluated by 8-isoprostane concentrations; loss of antioxidant defenses such as glutathione reductase (GR) activity; NF-kappaB activation and loss of cytoplasmic IkappaBalpha protein; increases in tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), caspase-3, and caspase-7 gene expression and their related protein; accumulation and activation of neutrophils in the damaged tissue, evaluated by elastase (ELA) determination; and pancreatic injury, evaluated by histologic analysis. Pretreatment of mice with different doses of C4S, given 1 hr before caerulein injections and 1 and 2 hrs after the last caerulein injection, reduced lipid peroxidation, inhibited NF-kappaB translocation and cytoplasmic IkappaBalpha protein loss, decreased TNF-alpha, IL-6, and caspase gene expression and their related protein levels, limited endogenous antioxidant depletion, and reduced tissue neutrophils accumulation and tissue damage. Since molecules with antioxidant activity can block NF-kappaB and apoptosis activation, we suggest that C4S administration is able to block NF-kappaB and caspase activation by reducing the oxidative burst.