Fibroblast-Like Synoviocytes Glucose Metabolism as a Therapeutic Target in Rheumatoid Arthritis.

Metabolomic studies show that rheumatoid arthritis (RA) is associated with metabolic disruption that may be therapeutically targetable. Among them, glucose metabolism and glycolytic intermediaries seem to have an important role in fibroblast-like synoviocytes (FLS) phenotype and might contribute to early stage disease pathogenesis. RA FLS are transformed from quiescent to aggressive and metabolically active cells and several works have shown that glucose metabolism is increased in activated FLS. Glycolytic inhibitors reduce not only FLS aggressive phenotype in vitro but also decrease bone and cartilage damage in several murine models of arthritis. Essential glycolytic enzymes, including hexokinase 2 (HK2) and 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase (PFKFB) enzymes, have important roles in FLS behavior. Of interest, HK2 is an inducible enzyme present only in the inflamed rheumatic tissues compared to osteoarthritis synovium. It is a contributor to glucose metabolism that could be selectively targeted without compromising systemic homeostasis as a novel approach for combination therapy independent of systemic immunosuppression. More information about metabolic targets that do not compromise global glucose metabolism in normal cells is needed

Manejo y uso de residuos sólidos en la escuela ―La Curva‖, comunidad Guadalupe Matagalpa, segundo semestre 2010

El Manejo y uso de residuos sólidos en la escuela La Curva, comunidad Guadalupe Matagalpa segundo semestre 2010. La escuela cuenta con una población de 164 estudiantes, 4 docentes y el director del Núcleo Educativo Rural (NER:) Nº 20, para un total de 169 personas. Se tomó como muestra los estudiantes de quinto y sexto grado, ya que se considera que son niños que pueden brindar información del manejo y uso de residuos sólidos en la escuela, cuatro docentes y director. Para adquirir esta información se aplicaron encuesta a 45 estudiantes de quinto y sexto grado del turno vespertino, entrevista a docentes y director; cuatro guías de observación al turno matutino y al turno vespertino. La investigación es descriptiva con enfoque teórico Al procesar la información se encontró las siguientes resultados, en la escuela no existe clasificación de los residuos sólidos. El manejo y uso de los residuos sólidos en la escuela está dado por la recolección, almacenamiento, quema, elaboración de manualidades y abono orgánico con iniciativa de los docentes. Los residuos sólidos que más se generan en la escuela, son orgánicos e inorgánicos. Para reducir el volumen de residuos sólidos en la escuela ―La Curva‖ es necesario que el MINED implemente un plan de acción para darle un uso adecuado a los residuos sólidos y capacitar a los docentes. Ubicar recipiente diferenciados para depositar las diferentes clasificaciones de residuos sólidos en la escuela. Impulsar campaña de sensibilización a comunidad educativa de la escuela ―La Curva

Role of mitochondria-bound HK2 in rheumatoid arthritis fibroblast-like synoviocytes

BackgroundGlucose metabolism, specifically, hexokinase 2 (HK2), has a critical role in rheumatoid arthritis (RA) fibroblast-like synoviocyte (FLS) phenotype. HK2 localizes not only in the cytosol but also in the mitochondria, where it protects mitochondria against stress. We hypothesize that mitochondria-bound HK2 is a key regulator of RA FLS phenotype.MethodsHK2 localization was evaluated by confocal microscopy after FLS stimulation. RA FLSs were infected with Green fluorescent protein (GFP), full-length (FL)-HK2, or HK2 lacking its mitochondrial binding motif (HK2ΔN) expressing adenovirus (Ad). RA FLS was also incubated with methyl jasmonate (MJ; 2.5 mM), tofacitinib (1 µM), or methotrexate (1 µM). RA FLS was tested for migration and invasion and gene expression. Gene associations with HK2 expression were identified by examining single-cell RNA sequencing (scRNA-seq) data from murine models of arthritis. Mice were injected with K/BxN serum and given MJ. Ad-FLHK2 or Ad-HK2ΔN was injected into the knee of wild-type mice.ResultsCobalt chloride (CoCl2) and platelet-derived growth factor (PDGF) stimulation induced HK2 mitochondrial translocation. Overexpression of the HK2 mutant and MJ incubation reversed the invasive and migrative phenotype induced by FL-HK2 after PDGF stimulation, and MJ also decreased the expression of C-X-C Motif Chemokine Ligand 1 (CXCL1) and Collagen Type I Alpha 1 Chain (COL1A1). Of interest, tofacitinib but not methotrexate had an effect on HK2 dissociation from the mitochondria. In murine models, MJ treatment significantly decreased arthritis severity, whereas HK2FL was able to induce synovial hypertrophy as opposed to HK2ΔN.ConclusionOur results suggest that mitochondrial HK2 regulates the aggressive phenotype of RA FLS. New therapeutic approaches to dissociate HK2 from mitochondria offer a safer approach than global glycolysis inhibition

In vitro antileishmanial activity and iron superoxide dismutase inhibition of arylamine Mannich base derivatives

Leishmaniasis is one of the world’s most neglected diseases, and it has a worldwide prevalence of 12 million. There are no effective human vaccines for its prevention, and treatment is hampered by outdated drugs. Therefore, research aiming at the development of new therapeutic tools to fight Leishmaniasis remains a crucial goal today. With this purpose in mind, we present twenty arylaminoketone derivatives with a very interesting in vitro and in vivo efficacy against Trypanosoma cruzi that have now been studied against promastigote and amastigote forms of L. infantum, L. donovani and L. braziliensis strains. Six out of the twenty Mannich base-type derivatives showed Selectivity Index between 39 and 2337 times higher in the amastigote form than the reference drug glucantime. These six derivatives affected the parasite infectivity rates; the result was lower parasite infectivity rates than glucantime tested at a IC25 dose. In addition, these derivatives were substantially more active against the three Leishmania species tested than glucantime. The mechanism of action of these compounds has been studied, showing a greater alteration in glucose catabolism and leading to greater levels of Fe-SOD (iron superoxide dismutase) inhibition. These molecules could be potential candidates for Leishmaniasis chemotherapy

In vitro and in vivo anti-Trypanosoma cruzi activity of new arylamine Mannich base-type derivatives

Chagas disease is a neglected tropical disease with 6-7 million people infected worldwide and there is no effective treatment. Therefore, there is an urgent need to continue researching in order to discover novel therapeutic alternatives. We present a series of arylaminoketone derivatives as means of identifying new drugs to treat Chagas disease in the acute phase with greater activity, less toxicity and with a larger spectrum of action than that corresponding to the reference drug benznidazole. Indexes of high selectivity found in vitro formed the basis for later in vivo assays in BALB/c mice. Murine model results show that compounds 3, 4, 7 and 10 induced a remarkable decrease in parasitemia levels in acute phase and the parasitemia reactivation following immunosuppression, and curative rates were higher than with benznidazole. These high anti-parasitic activities encourage us to propose these compounds as promising molecules for developing an easy to synthesize anti-Chagas agent

NF-κB Restricts Inflammasome Activation via Elimination of Damaged Mitochondria

Nuclear factor κB (NF-κB), a key activator of inflammation, primes the NLRP3-inflammasome for activation by inducing pro-IL-1β and NLRP3 expression. NF-κB, however, also prevents excessive inflammation and restrains NLRP3-inflammasome activation through a poorly defined mechanism. We now show that NF-κB exerts its anti-inflammatory activity by inducing delayed accumulation of the autophagy receptor p62/SQSTM1. External NLRP3-activating stimuli trigger a form of mitochondrial (mt) damage that is caspase-1- and NLRP3-independent and causes release of direct NLRP3-inflammasome activators, including mtDNA and mtROS. Damaged mitochondria undergo Parkin-dependent ubiquitin conjugation and are specifically recognized by p62, which induces their mitophagic clearance. Macrophage-specific p62 ablation causes pronounced accumulation of damaged mitochondria and excessive IL-1β-dependent inflammation, enhancing macrophage death. Therefore, the "NF-κB-p62-mitophagy" pathway is a macrophage-intrinsic regulatory loop through which NF-κB restrains its own inflammation-promoting activity and orchestrates a self-limiting host response that maintains homeostasis and favors tissue repair

Hexokinase 2 as a novel selective metabolic target for rheumatoid arthritis

Objectives: Recent studies indicate that glucose metabolism is altered in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS). Hexokinases (HK) is catalyze the first step in glucose metabolism and HK2 constitutes the principal HK inducible isoform. We hypothesize that HK2 contributes to the synovial lining hypertrophy and plays a critical role in bone and cartilage damage. Methods: HK1 and HK2 expression were determined in RA and osteoarthritis (OA) synovial tissue by immunohistochemistry. RA FLS were transfected with either HK1 or HK2 siRNA, or infected with either adenovirus (ad)-GFP, ad-HK1 or ad-HK2. FLS migration and invasion were assessed. To study the role of HK2 in vivo, 108 particles of ad-HK2 or ad-GFP were injected into the knee of WT mice. K/BxN serum-transfer arthritis was induced in HK2F/F mice harboring Col1a1-Cre (HK2Col1), to delete HK2 in non-hematopoietic cells. Results: HK2 is particular of RA histopathology (9/9 RA; 1/8 OA) and co-localizes with FLS markers. Silencing HK2 in RA FLS resulted in a less invasive and migratory phenotype. Consistently, overexpression of HK2 resulted in an increased ability to migrate and invade. It also increased extracellular lactate production. Intra-articular injection of ad-HK2 in normal knees dramatically increased synovial lining thickness, FLS activation and proliferation. HK2 was highly expressed in the synovial lining after K/BxN serum transfer arthritis. HK2Col1 mice significantly showed decreased arthritis severity, bone and cartilage damage.Conclusion: HK2 is specifically expressed in RA synovial lining and regulates FLS aggressive functions. HK2 might be an attractive selective metabolic target safer than global glycolysis for RA treatment

Regulatory T Cell Expansion in HTLV-1 and Strongyloidiasis Co-infection Is Associated with Reduced IL-5 Responses to Strongyloides stercoralis Antigen

Human strongyloidiasis varies from a mild, controlled infection to a severe frequently fatal disseminated infection depending on the hosts. Patients infected with the retrovirus HTLV-1 have more frequent and more severe forms of strongyloidiasis. It is not clear how human strongyloidiasis is controlled by the immune system and how HTLV-1 infection affects this control. We hypothesize that HTLV-1 leads to dissemination of Strongyloides stercoralis by augmenting regulatory T cell numbers, which in turn down regulate the immune response to the parasite. In our study, patients with HTLV-1 and Strongyloides co-infection had higher parasite burdens than patients with only strongyloidiasis. Eosinophils play an essential role in control of strongyloidiasis in animal models, and eosinophil counts were decreased in the HTLV-1 and Strongyloides stercoralis co-infected subjects compared to patients with only strongyloidiasis. The proportion of T cells with a regulatory cell phenotype was increased in HTLV-1 positive subjects co-infected with strongyloidiasis compared to patients with only strongyloidiasis. IL-5 is a key host molecule in stimulating eosinophil production and activation, and Strongyloides stercoralis antigen-specific IL-5 responses were reduced in strongyloidiasis/HTLV-1 co-infected patients. Reduced IL-5 responses and eosinophil counts were inversely correlated to the number of regulatory T cells. These findings suggest a role for regulatory T cells in susceptibility to Strongyloides hyperinfection