The thyroid hormone triiodothyronine controls macrophage maturation and functions: protective role during inflammation.

The endocrine system participates in regulating macrophage maturation, although little is known about the modulating role of the thyroid hormones. In vitro results demonstrate a negative role of one such hormone, triiodothyronine (T 3 ), in triggering the differentiation of bone marrow–derived monocytes into unpolarized macrophages. T 3 -induced macrophages displayed a classically activated (M1) signature. A T 3 -induced M1-priming effect was also observed on polarized macrophages because T 3 reverses alternatively activated (M2) activation, whereas it enhances that of M1 cells. In vivo , circulating T 3 increased the content of the resident macrophages in the peritoneal cavity, whereas it reduced the content of the recruited monocyte-derived cells. Of interest, T 3 significantly protected mice against endotoxemia induced by lipopolysaccharide i.p. injection; in these damaged animals, decreased T 3 levels increased the recruited (potentially damaging) cells, whereas restoring T 3 levels decreased recruited and increased resident (potentially beneficial) cells. These data suggest that the anti-inflammatory effect of T 3 is coupled to the modulation of peritoneal macrophage content, in a context not fully explained by the M1/M2 framework. Thyroid hormone receptor expression analysis and the use of different thyroid hormone receptor antagonists suggest thyroid hormone receptor β1 as the major player mediating T 3 effects on macrophages. The novel homeostatic link between thyroid hormones and the pathophysiological role of macrophages opens new perspectives on the interactions between the endocrine and immune systems

Insights into the safety and versatility of 4D printed intravesical drug delivery systems

This paper focuses on recent advancements in the development of 4D printed drug delivery systems (DDSs) for the intravesical administration of drugs. By coupling the effectiveness of local treatments with major compliance and long-lasting performance, they would represent a promising innovation for the current treatment of bladder pathologies. Being based on a shape-memory pharmaceutical-grade polyvinyl alcohol (PVA), these DDSs are manufactured in a bulky shape, can be programmed to take on a collapsed one suitable for insertion into a catheter and re-expand inside the target organ, following exposure to biological fluids at body temperature, while releasing their content. The biocompatibility of prototypes made of PVAs of different molecular weight, either uncoated or coated with Eudragit®-based formulations, was assessed by excluding relevant in vitro toxicity and inflammatory response using bladder cancer and human monocytic cell lines. Moreover, the feasibility of a novel configuration was preliminarily investigated, targeting the development of prototypes provided with inner reservoirs to be filled with different drug-containing formulations. Samples entailing two cavities, filled during the printing process, were successfully fabricated and showed, in simulated urine at body temperature, potential for controlled release, while maintaining the ability to recover about 70% of their original shape within 3 min

The protein pheromone Er-1 of the ciliate Euplotes raikovi stimulates humanT-cell activity: Involvement of interleukin-2 system

Water-soluble protein signals (pheromones) of the ciliate Euplotes have been supposed to be functional precursors of growth factors and cytokines that regulate cell–cell interactionin multi-cellular eukaryotes.This work provides evidence that native preparations of the Euplotes raikovi pheromone Er-1 (a helical protein of 40 aminoacids) specifically increases viability, DNA synthesis, proliferation, and the production of interferon-g, tumor necrosis factor-a, interleukin (IL)-1b, IL-2, and IL-13 in human Jurkat T-cells. Also, Er-1 significantly decreases them RNA levels of the b and g subunits of IL-2 receptor(IL-2R), while them RNA levels of the a subunit appeared to be not affected. Jurkat T-cell treatments with Er-1 induced the down-regulation of the IL-2Ra subunit by a reversible and time-dependent endocytosis, and increased the levels of phosphorylation of the extracellular signal-regulated kinases (ERK). The cell-type specificity of these effects was supported by the finding that Er-1, although unable to directly influence the growth of human glioma U373 cells, induced Jurkat cells to synthesize and release factors that, in turn, inhibited the U373 cell proliferation. Overall, these findings imply that Er-1 coupling to IL-2R and ERK immuno-enhances T-cell activity, and that this effect likely translates to an inhibition of glioma cell growth

Acid sphingomyelinase activity triggers microparticle release from glial cells

We have earlier shown that microglia, the immune cells of the CNS, release microparticles from cell plasma membrane after ATP stimulation. These vesicles contain and release IL-1β, a crucial cytokine in CNS inflammatory events. In this study, we show that microparticles are also released by astrocytes and we get insights into the mechanism of their shedding. We show that, on activation of the ATP receptor P2X7, microparticle shedding is associated with rapid activation of acid sphingomyelinase, which moves to plasma membrane outer leaflet. ATP-induced shedding and IL-1β release are markedly reduced by the inhibition of acid sphingomyelinase, and completely blocked in glial cultures from acid sphingomyelinase knockout mice. We also show that p38 MAPK cascade is relevant for the whole process, as specific kinase inhibitors strongly reduce acid sphingomyelinase activation, microparticle shedding and IL-1β release. Our results represent the first demonstration that activation of acid sphingomyelinase is necessary and sufficient for microparticle release from glial cells and define key molecular effectors of microparticle formation and IL-1β release, thus, opening new strategies for the treatment of neuroinflammatory diseases

Essential role for acid sphingomyelinase-inhibited autophagy in melanoma response to cisplatin

In advanced stages, melanoma is still a therapeutic challenge, despite the large number of chemotherapeutic regimens so far developed. Single drug chemotherapy is in many cases ineffective and combinations of chemotherapeutic drugs have demonstrated response rates only marginally higher, and at the cost of systemic toxicity. The new targeted therapies and immunotherapies have shown better efficacy and have supplanted chemotherapy as first-and second-line therapy. However, since melanoma cells eventually become resistant also to these novel therapies, the quest for new, more effective and possibly less toxic approaches is still open. The sphingolipid metabolising enzyme Acid Sphingomyelinase (A-SMase) has been recently shown to inhibit melanoma progression and correlate inversely to tumour grade [1]. We have investigated the role of A-SMase in the chemo-resistance to anticancer treatment using mice with melanoma allografts and melanoma cells differing in terms of expression/activity of A-SMase. Furthermore, as autophagy is a crucial determinant of the melanoma sensitivity to chemotherapeutic drugs, we have also investigated whether an action of A-SMase in autophagy can explain its role [2]. Melanoma sensitivity to chemotherapeutic agent cisplatin in terms of cell viability/apoptosis, tumour growth, and animal survival depended directly on the A-SMase levels in tumoural cells. A-SMase action was due to inhibition of autophagy through activation of Akt/mammalian target of rapamycin (mTOR) pathway. Treatment of melanoma-bearing mice with the autophagy inhibitor chloroquine restored sensitivity to cisplatin of tumours expressing low levels of A-SMase while no additive effects were observed in tumours characterised by sustained A-SMase levels. In conclusion A-SMase, affecting mTOR-regulated autophagy and playing a central role in cisplatin efficacy, is an attractive target in anti-tumour strategy for melanomas and our data encourage pre-clinical testing of the modulation of A-SMase levels/activity as possible novel anti-neoplastic strategy

Drp1 overexpression induces desmin disassembling and drives kinesin-1 activation promoting mitochondrial trafficking in skeletal muscle

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The Natural Compound Climacostol as a Prodrug Strategy Based on pH Activation for Efficient Delivery of Cytotoxic Small Agents

We synthesized and characterized MOMO as a new small molecule analog of the cytotoxic natural product climacostol efficiently activated in mild extracellular acidosis. The synthesis of MOMO had a key step in the Wittig olefination for the construction of the carbon-carbon double bond in the alkenyl moiety of climacostol. The possibility of obtaining the target (Z)-alkenyl MOMO derivative in very good yield and without presence of the less active (E)-diastereomer was favored from the methoxymethyl ether (MOM)-protecting group of hydroxyl functions in aromatic ring of climacostol aldehyde intermediate. Of interest, the easy removal of MOM-protecting group in a weakly acidic environment allowed us to obtain a great quantity of climacostol in biologically active (Z)-configuration. Results obtained in free-living ciliates that share the same micro-environment of the climacostol natural producer Climacostomum virens demonstrated that MOMO is well-tolerated in a physiological environment, while its cytotoxicity is rapidly and efficiently triggered at pH 6.3. In addition, the cytostatic vs. cytotoxic effects of acidified-MOMO can be modulated in a dose-dependent manner. In mouse melanoma cells, MOMO displayed a marked pH-sensitivity since its cytotoxic and apoptotic effects become evident only in mild extracellular acidosis. Data also suggested MOMO being preferentially activated in the unique extra-acidic microenvironment that characterizes tumoural cells. Finally, the use of the model organism Drosophila melanogaster fed with an acidic diet supported the efficient activity and oral delivery of MOMOmolecule in vivo.MOMO affected oviposition ofmating adults and larvae eclosion. Reduced survival of flies was due to lethality during the larval stages while emerging larvae retained their ability to develop into adults. Interestingly, the gut of eclosed larvae exhibited an extended damage (cell death by apoptosis) and the brain tissue was also affected (reduced mitosis), demonstrating that orally activated MOMO efficiently targets different tissues of the developing fly. These results provided a proof-of-concept study on the pHdependence of MOMO effects. In this respect, MOM-protection emerges as a potential prodrug strategy which deserves to be further investigated for the generation of efficient pH-sensitive small organic molecules as pharmacologically active cytotoxic compounds

Nitric Oxide Confers Therapeutic Activity to Dendritic Cells in a Mouse Model of Melanoma

Susceptibility of dendritic cells (DCs) to tumor-induced apoptosis reduces their efficacy in cancer therapy. Here we show that delivery within exponentially growing B16 melanomas of DCs treated ex vivo with nitric oxide (NO), released by the NO donor (z)-1-[2-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate (DETA-NO), significantly reduced tumor growth, with cure of 37% of animals. DETA-NO-treated DCs became resistant to tumor-induced apoptosis because DETA-NO prevented tumor-induced changes in the expression of Bcl-2, Bax, and Bcl-xL; activation of caspase-9; and a reduction in the mitochondrial membrane potential. DETA-NO also increased DC cytotoxic activity against tumor cells and DC ability to trigger T-lymphocyte proliferation. All of the effects of DETA-NO were mediated through cGMP generation. NO and NO-generating drugs may therefore be used to increase the anticancer efficacy of DCs

Reversal of Defective Mitochondrial Biogenesis in Limb-Girdle Muscular Dystrophy 2D by Independent Modulation of Histone and PGC-1α Acetylation

Mitochondrial dysfunction occurs in many muscle degenerative disorders. Here, we demonstrate that mitochondrial biogenesis was impaired in limb-girdle muscular dystrophy (LGMD) 2D patients and mice and was associated with impaired OxPhos capacity. Two distinct approaches that modulated histones or peroxisome proliferator-activated receptor-gamma coactivator 1 \u3b1 (PGC-1\u3b1) acetylation exerted equivalent functional effects by targeting different mitochondrial pathways (mitochondrial biogenesis or fatty acid oxidation[FAO]). The histone deacetylase inhibitor Trichostatin A (TSA) changed chromatin assembly at the PGC-1\u3b1 promoter, restored mitochondrial biogenesis, and enhanced muscle oxidative capacity. Conversely, nitric oxide (NO) triggered post translation modifications of PGC-1\u3b1 and induced FAO, recovering the bioenergetics impairment of muscles but shunting the defective mitochondrial biogenesis. In conclusion, a transcriptional blockade of mitochondrial biogenesis occurred in LGMD-2D and could be recovered by TSA changing chromatin conformation, or it could be overcome by NO activating a mitochondrial salvage pathway