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1.  Targeting autophagy as a novel strategy for facilitating the therapeutic action of potentiators on ΔF508 cystic fibrosis transmembrane conductance regulator 
Autophagy  2012;8(11):1657-1672.
Channel activators (potentiators) of cystic fibrosis (CF) transmembrane conductance regulator (CFTR), can be used for the treatment of the small subset of CF patients that carry plasma membrane-resident CFTR mutants. However, approximately 90% of CF patients carry the misfolded ΔF508-CFTR and are poorly responsive to potentiators, because ΔF508-CFTR is intrinsically unstable at the plasma membrane (PM) even if rescued by pharmacological correctors. We have demonstrated that human and mouse CF airways are autophagy deficient due to functional sequestration of BECN1 and that the tissue transglutaminase-2 inhibitor, cystamine, or antioxidants restore BECN1-dependent autophagy and reduce SQSTM1/p62 levels, thus favoring ΔF508-CFTR trafficking to the epithelial surface. Here, we investigated whether these treatments could facilitate the beneficial action of potentiators on ΔF508-CFTR homozygous airways. Cystamine or the superoxide dismutase (SOD)/catalase-mimetic EUK-134 stabilized ΔF508-CFTR at the plasma membrane of airway epithelial cells and sustained the expression of CFTR at the epithelial surface well beyond drug withdrawal, overexpressing BECN1 and depleting SQSTM1. This facilitates the beneficial action of potentiators in controlling inflammation in ex vivo ΔF508-CFTR homozygous human nasal biopsies and in vivo in mouse ΔF508-CFTR lungs. Direct depletion of Sqstm1 by shRNAs in vivo in ΔF508-CFTR mice synergized with potentiators in sustaining surface CFTR expression and suppressing inflammation. Cystamine pre-treatment restored ΔF508-CFTR response to the CFTR potentiators genistein, Vrx-532 or Vrx-770 in freshly isolated brushed nasal epithelial cells from ΔF508-CFTR homozygous patients. These findings delineate a novel therapeutic strategy for the treatment of CF patients with the ΔF508-CFTR mutation in which patients are first treated with cystamine and subsequently pulsed with CFTR potentiators.
PMCID: PMC3494594  PMID: 22874563
cystic fibrosis; autophagy; therapy; cystamine; CFTR potentiators
2.  Macrophage Autophagy in Atherosclerosis 
Mediators of Inflammation  2013;2013:584715.
Macrophages play crucial roles in atherosclerotic immune responses. Recent investigation into macrophage autophagy (AP) in atherosclerosis has demonstrated a novel pathway through which these cells contribute to vascular inflammation. AP is a cellular catabolic process involving the delivery of cytoplasmic contents to the lysosomal machinery for ultimate degradation and recycling. Basal levels of macrophage AP play an essential role in atheroprotection during early atherosclerosis. However, AP becomes dysfunctional in the more advanced stages of the pathology and its deficiency promotes vascular inflammation, oxidative stress, and plaque necrosis. In this paper, we will discuss the role of macrophages and AP in atherosclerosis and the emerging evidence demonstrating the contribution of macrophage AP to vascular pathology. Finally, we will discuss how AP could be targeted for therapeutic utility.
PMCID: PMC3563164  PMID: 23401644
3.  Nanomaterials Toxicity and Cell Death Modalities 
Journal of Drug Delivery  2012;2012:167896.
In the last decade, the nanotechnology advancement has developed a plethora of novel and intriguing nanomaterial application in many sectors, including research and medicine. However, many risks have been highlighted in their use, particularly related to their unexpected toxicity in vitro and in vivo experimental models. This paper proposes an overview concerning the cell death modalities induced by the major nanomaterials.
PMCID: PMC3523142  PMID: 23304518
4.  PEI-Engineered Respirable Particles Delivering a Decoy Oligonucleotide to NF-κB: Inhibiting MUC2 Expression in LPS-Stimulated Airway Epithelial Cells 
PLoS ONE  2012;7(10):e46457.
A specific and promising approach to limit inflammation and mucin iperproduction in chronic lung diseases relies on specific inhibition of nuclear Factor-κB (NF-κB) by a decoy oligonucleotide (dec-ODN). To fulfill the requirements dictated by translation of dec-ODN therapy in humans, inhalable dry powders were designed on a rational basis to provide drug protection, sustained release and to optimize pharmacological response. To this end, large porous particles (LPP) for dec-ODN delivery made of a sustained release biomaterial (poly(lactic-co-glycolic) acid, PLGA) and an “adjuvant” hydrophilic polymer (polyethylenimine, PEI) were developed and their effects on LPS-stimulated human airway epithelial cells evaluated. The composite PLGA/PEI particles containing dec-ODN (i.e., LPPPEI) were successfully engineered for widespread deposition in the lung and prolonged release of intact dec-ODN in vitro. LPPPEI caused a prolonged inhibition of IL-8 and MUC2 expression in CF human bronchial epithelial cells and human epithelial pulmonary NCI-H292 cells, respectively, as compared to naked dec-ODN. Nonetheless, as compared to previously developed LPP, the presence of PEI was essential to construct a dec-ODN delivery system able to act in mucoepidermoid lung epithelial cells. In perspective, engineering LPP with PEI may become a key factor for tuning carrier properties, controlling lung inflammation and mucin production which, in turn, can foster in vivo translation of dec-ODN therapy.
PMCID: PMC3463602  PMID: 23056313
5.  Cacospongionolide and Scalaradial, Two Marine Sesterterpenoids as Potent Apoptosis-Inducing Factors in Human Carcinoma Cell Lines 
PLoS ONE  2012;7(4):e33031.
Apoptosis, a form of programmed cell death, is a critical defence mechanism against the formation and progression of cancer and acts by eliminating potentially deleterious cells without causing such adverse effects, as inflammatory response and ensuing scar formation. Therefore, targeting apoptotic pathways becomes an intriguing strategy for the development of chemotherapeutic agents. In last decades, marine natural products, such as sesterterpenoids, have played an important role in the discovery and development of new drugs. Interestingly, many of these compounds have a strong potential as anticancer drugs by inhibiting cell proliferation and/or inducing cell death. In the present study, we investigated the effects of scalaradial and cacospongionolide, two sesterterpenoids from Cacospongia scalaris and Fasciospongia cavernosa marine sponges, on the apoptotic signalling pathway in three different human tumoral cells. Results were obtained by using DNA fragmentation, comet and viability assays, quantification of the mitochondrial transmembrane potential and Western blot. The T47D (human breast carcinoma), A431 (human epidermoid carcinoma), HeLa (human cervix carcinoma) and HCT116 (human colon carcinoma) cells were incubated for 24 h with scalaradial or cacospongionolide. Treatment of T47D cells with scalaradial or cacospongionolide for 24 h brought about a significant increase in DNA migration as well as fragmentation. Moreover, incubation of HCT116 and HeLa cells with scalaradial or cacospongionolide for 24 h caused an increased expression of pro-apoptotic proteins. Furthermore, scalaradial or cacospongionolide, added to HCT116 and HeLa cells overnight, induced a significant and concentration-dependent loss of mitochondrial transmembrane potential, an early apoptosis signalling event. These effects paralleled with those achieved with p50 and p65, NF-κB subunits, nuclear level. In conclusion, scalaradial and cacospongionolide, by determining human cancer cell apoptosis, may represent new promising compounds to inhibit cancer cell proliferation.
PMCID: PMC3317917  PMID: 22509253
6.  Palmitoylethanolamide counteracts reactive astrogliosis induced by β-amyloid peptide 
Emerging evidence indicates that astrogliosis is involved in the pathogenesis of neurodegenerative disorders. Our previous findings suggested cannabinoids and Autacoid Local Injury Antagonism Amides (ALIAmides) attenuate glial response in models of neurodegeneration. The present study was aimed at exploring palmitoylethanolamide (PEA) ability to mitigate β-amyloid (Aβ)-induced astrogliosis. Experiments were carried out to investigate PEA’s (10−7M) effects upon the expression and release of pro-inflammatory molecules in rat primary astrocytes activated by soluble Aβ1–42 (1 μg/ml) as well as to identify mechanisms responsible for such actions. The effects of Aβ and exogenous PEA on the astrocyte levels of the endocannabinoidsand of endogenous ALIAmides were also studied. The peroxisome proliferator-activated receptor (PPAR)-α (MK886, 3 μM) or PPAR-γ (GW9662, 9 nM) antagonists were co-administered with PEA. Aβ elevated endogenous PEA and d5–2-arachidonoylglycerol (2-AG) levels. Exogenous PEA blunted the Aβ-induced expression of pro-inflammatory molecules. This effect was reduced by PPAR-α antagonist. Moreover, this ALIAmide, like Aβ, increased 2-AG levels. These results indicate that PEA exhibits anti-inflammatory properties able to counteract Aβ-induced astrogliosis, and suggest novel treatment for neuroinflammatory/ neurodegenerative processes.
PMCID: PMC4373435  PMID: 21255263
astrocyte; β amyloid; palmitoylethanolamide; PPAR; neuroinflammation
7.  Regulation of autophagy by cytoplasmic p53 
Nature cell biology  2008;10(6):676-687.
Multiple cellular stressors, including activation of the tumour suppressor p53, can stimulate autophagy. Here we show that knockout, knockdown or pharmacological inhibition of p53 can induce autophagy in human, mouse and nematode cells. Enhanced autophagy improved the survival of p53-deficient cancer cells under conditions of hypoxia and nutrient depletion, allowing them to maintain high ATP levels. Inhibition of p53 led to autophagy in enucleated cells, and cytoplasmic, not nuclear, p53 was able to repress the enhanced autophagy of p53-/- cells. Many different inducers of autophagy (for example, starvation, rapamycin and toxins affecting the endoplasmic reticulum) stimulated proteasome-mediated degradation of p53 through a pathway relying on the E3 ubiquitin ligase HDM2. Inhibition of p53 degradation prevented the activation of autophagy in several cell lines, in response to several distinct stimuli. These results provide evidence of a key signalling pathway that links autophagy to the cancer-associated dysregulation of p53.
PMCID: PMC2676564  PMID: 18454141
8.  Inflammatory events in a vascular remodeling model induced by surgical injury to the rat carotid artery 
British Journal of Pharmacology  2005;147(2):175-182.
The aim of our study was to gain insight into the molecular and cellular mechanisms of the inflammatory response to arterial injury in a rat experimental model.Rats (five for each experimental time) were subjected to brief clamping and longitudinal incision of a carotid artery and monitored for 30 days. Subsequently, Nuclear Factor-kappaB (NF-κB) expression was measured by electrophoretic mobility shift assay. Heat shock protein (HSP) 27, HSP47 and HSP70 were evaluated by Western blot. Morphological changes of the vessel wall were investigated by light and electron microscopy.In injured rat carotid artery NF-κB activity started immediately upon injury, and peaked between 2 and 3 weeks later. Western blot showed a significant increase of HSP47 and HSP70 7 days after injury. At 2 weeks postinjury, HSP27 expression peaked. Ligth microscopy showed a neointima formation, discontinuity of the media layer and a rich infiltrate. Among infiltrating cells electron microscopy identified dendritic-like cells in contact with lymphocytes.Our model of surgical injury induces a significant inflammatory process characterized by enhanced NF-κB activity and HSPs hyperexpression. Dendritic-like cells were for the first time identified as a novel component of tissue repair consequent to acute arterial injury.
PMCID: PMC1615853  PMID: 16299548
Nuclear factor kappa B; heat shock protein; carotid injury; remodeling
9.  Evidence that mast cell degranulation, histamine and tumour necrosis factor α release occur in LPS-induced plasma leakage in rat skin 
British Journal of Pharmacology  1999;128(3):700-704.
In the present study we investigated the role of mast cells during inflammation in rat skin. As the release of several pro-inflammatory mediators, such as histamine and tumour necrosis factor α (TNFα), occurs following mast cell activation we studied whether mast cell degranulation and the release of both histamine (H) and TNFα occurred in a model of lipopolysaccharide (LPS)-induced plasma leakage in rat skin.Plasma leakage in the rat skin was measured over a period of 2 h as the local accumulation of intravenous injection of 125I-human serum albumin (125I-HSA) in response to intradermal injection of LPS. LPS (10 μg site−1) produced an increase of plasma leakage (50.1±2.3 μl site−1) as compared to saline (9.0±3.2 μl site−1). Histological analysis of rat tissue showed that LPS induced a remarkable mast cell degranulation (59.8±2.1%) as compared to saline (13.5±2.2%).Ketotifen (10−9–10−7 mol site−1), a well-known mast cell-membrane stabilizer, produced a dose-related inhibition of LPS-induced plasma leakage by 36±3.5%, 47±4.0%, 60±3.3% respectively. In addition, ketotifen (10−7 mol site−1) inhibited mast cell degranulation by 59.2±2.7%.Chlorpheniramine maleate (CPM) (10−9–10−7 mol site−1), an H1 histamine receptor antagonist only partially inhibited LPS-induced plasma leakage in rat skin (38±1.1% at the highest dose). Furthermore, CPM (10−7 mol site−1) did not prevent mast cell degranulation.A polyclonal antibody against TNFα (1 : 500, 1 : 100, 1 : 50 v  v−1 dilution), locally injected, decreased LPS-induced plasma leakage in the skin by 15±2.0%, 24±2.1% and 50±3.0% respectively.Taken together these results suggest that LPS-induced plasma leakage in rat skin is mediated, at least in part, by mast cell degranulation and by the release of histamine and TNFα from these cells.
PMCID: PMC1571670  PMID: 10516651
LPS; plasma leakage; mast cell degranulation; TNFα; ketotifen; histamine
10.  Evidence that inducible nitric oxide synthase is involved in LPS-induced plasma leakage in rat skin through the activation of nuclear factor-κB 
British Journal of Pharmacology  1998;123(7):1325-1330.
Rats challenged with lipopolysaccharide (LPS) produce large amounts of nitric oxide (NO) following the induction of the inducible NO-synthase (iNOS) in several tissues and organs. Recent studies have shown that the expression of iNOS is regulated at the transcriptional level by a transcription nuclear factor-κB (NF-κB). In this study we investigated the role of NO in a model of LPS-induced plasma-leakage in rat skin and the involvement of NF-κB.Plasma leakage in the rat skin was measured over a period of 30 min to 2 h as the local accumulation of intravenous (i.v.) injection of [125I]-human serum albumin ([125I]-HSA) in response to intradermal (i.d.) injection of LPS. LPS (1, 10, 100 μg/site) produced a dose-related increase in plasma extravasation (18.2±3.2, 27.2±2.9, 40.4±9.6 μl/site) as compared to saline control (11.4±2.2 μl/site). This increase was maximal after 2 h; therefore this time point and the dose of LPS 10 μg/site was used in all the successive experiments.To investigate the role of NO in LPS-induced plasma leakage in rat skin, the non-selective NOS inhibitor NGnitro-L-arginine-methyl ester (L-NAME) or the more selective iNOS inhibitor S-methyl-isothiourea (SMT) was injected i.d. with LPS. L-NAME and SMT (0.01, 0.1 and 1 μmol/site) inhibited LPS-induced plasma leakage in a dose-related fashion (L-NAME: 26.0±5.5, 20.2±1.6, 18.0±2.0 μl/site; SMT: 19.5±1.5, 17.0±1.6, 15.0±2.6 μl/site) as compared to LPS alone (27.2±2.9 μl/site). At the lowest concentration used (0.01 μmol/site), SMT significantly reduced plasma leakage by 30%±0.7 while L-NAME (0.01 μmol/site) was not effective.Treatment with increasing concentrations of pyrrolidinedithyocarbamate (PDTC) (0.01, 0.1, 1 μmol/site), an inhibitor of NF-κB activation, injected i.d. 30 min before LPS challenge, inhibited in a concentration-dependent fashion LPS-induced plasma leakage by 9.0±0.6, 33±4.0, 51±2.0% respectively. Moreover, PDTC (0.1, 1 μmol/site) suppressed LPS-induced NF-κB DNA-binding.Western blot analysis showed significant levels of iNOS proteins in the skin samples of LPS-treated rats, as compared to basal levels present in saline-injected rat skin. PDTC (0.1, 1.0 μmol/site) dose-dependently decreased the amount of iNOS protein expression induced by LPS.Our results indicate that LPS-induced plasma leakage in rat skin is modulated by NO mainly produced by the inducible isoform of NOS. Furthermore, the suppression of plasma leakage by PDTC, an inhibitor of NF-κB activation, is correlated to the inhibition of iNOS protein expression.
PMCID: PMC1565292  PMID: 9579726
LPS-induced plasma leakage; nitric oxide; iNOS; L-NAME; nuclear factor-κB
11.  Differential effect of L-NAME and S-methyl-isothiourea on leukocyte emigration in carrageenin-soaked sponge implants in rat 
British Journal of Pharmacology  1997;121(8):1637-1644.
The role of nitric oxide (NO) in leukocyte (polymorphonuclear cells, monocytes and lymphocytes) emigration was studied in a model of carrageenin-sponge implants in rats.The subcutaneous implantation of 1% (w/v) of λ-carrageenin-soaked sponges elicited an inflammatory response that was characterized by a time-related increase in leukocyte infiltration in the sponges and increased levels of nitrite in the exudate. Total leukocyte infiltration and nitrite production were maximal at 24 h and decreased after 48 and 96 h. The mononuclear cell influx was maximal at 48 h (21% of the total leukocytes). Therefore, this time point was used in the successive experiments.Polymorphonuclear cell (PMN) and lymphocyte infiltration in the sponges significantly increased when rats were treated with the non-specific NO-synthase (NOS) inhibitor, NG-nitro-L-arginine methylester (L-NAME) (1 mg ml−1 in drinking water ad libitum). Monocyte emigration was not affected by L-NAME treatment. The nitrite levels in the exudate of L-NAME-treated rats were significantly reduced. The concomitant ingestion of L-arginine (30 mg ml−1) resulted in a reversion of the L-NAME effect, while D-arginine (30 mg ml−1) had no effect, indicating the involvement of the L-arginine: NO pathway.Administration of L-NAME resulted also in an increased release of tumour necrosis factor-α (TNF-α) and prostacyclin (measured as the stable metabolite, 6-keto-PGF1α). L-NAME had no effect on monocyte chemoattractant protein-1 (MCP-1) release in the exudate.Since L-NAME may have effects on the local blood flow, phenylephrine (0.034 mg ml−2 in drinking water) was used as it has an effect on the local blood flow similar to L-NAME. Phenylephrine had no effect on either leukocyte emigration, or on nitrite, TNF-α, prostacyclin or MCP-1 accumulation in the exudate.In contrast, the more selective iNOS inhibitor S-methyl-isothiourea (SMT) (10 μg ml−1 in drinking water) significantly reduced PMNs and lymphocyte influx in the sponge, having no effect on monocyte influx. Moreover, SMT decreased nitrite production in the exudate to a comparable extent as L-NAME.Administration of SMT significantly reduced MCP-1 release in the exudate, without an effect on TNF-α or prostacyclin production. Moreover SMT did not produce any changes in local blood flow.Our results show that a different outcome of the inflammatory process can be obtained depending on the types of NOS inhibitor used.
PMCID: PMC1564873  PMID: 9283697
Nitric oxide; S-methyl-isothiourea; L-NAME; leukocyte emigration; PMNs; lymphocytes; carrageenin; sponge implants; TNF-α; prostacyclin; MCP-1; phenylephrine
12.  Vasocortin: a novel glucocorticoid-induced anti-inflammatory protein 
British Journal of Pharmacology  1987;90(3):443-445.
The preliminary characterization of `vasocortin' a novel glucocorticoid-induced anti-inflammatory protein, is described. Vasocortin is released into the rat peritoneal cavity following systemic dexamethasone administration, has an apparent mol. wt. of 100 kD and inhibits rat dextran oedema. Vasocortin is distinct from lipocortin and is likely to be associated with the anti-inflammatory effect of glucocorticoids.
PMCID: PMC1917188  PMID: 2952212

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