Molecular Aspects of Piperine in Signaling Pathways Associated with Inflammation in Head and Neck Cancer.

Piperine, an active plant alkaloid from black pepper (Piper nigrum), has several pharmacological effects, namely antioxidant, anti-inflammatory and immunomodulatory effects, which involve inhibiting molecular events associated with various stages of cancer development. The aim of this study was to investigate the molecular mechanisms of action of piperine in relation to its potential anticancer effect on head and neck cancer cells. Parameters related to neoplastic potential and cytokine, protein and gene expression were investigated in head and neck cancer cell lines (HEp-2 and SCC-25) treated with piperine. The results of the tests indicated that piperine modified morphology and inhibited viability and the formation of cell colonies. Piperine promoted genotoxicity by triggering apoptosis and cell cycle arrest in the G2/M and S phases. A decrease in cell migration was also observed, and there was decreased expression of MMP2/9 genes. Piperine also reduced the expression of inflammatory molecules (PTGS2 and PTGER4), regulated the secretion of cytokines (IFN-γ and IL-8) and modulated the expression of ERK and p38. These results suggest that piperine exerts anticancer effects on tumor cells by regulating signaling pathways associated with head and neck cancer.

The Role of Annexin A1 in DNA Damage Response in Placental Cells: Impact on Gestational Diabetes Mellitus.

The functions of annexin A1 (ANXA1), which is expressed on membranes and in cytoplasmic granules, have been fully described. Nonetheless, the role of this protein in protecting against DNA damage in the nucleus is still emerging and requires further investigation. Here, we investigated the involvement of ANXA1 in the DNA damage response in placental cells. Placenta was collected from ANXA1 knockout mice (AnxA1-/-) and pregnant women with gestational diabetes mellitus (GDM). The placental morphology and ANXA1 expression, which are related to the modulation of cellular response markers in the presence of DNA damage, were analyzed. The total area of AnxA1-/- placenta was smaller due to a reduced labyrinth zone, enhanced DNA damage, and impaired base excision repair (BER) enzymes, which resulted in the induction of apoptosis in the labyrinthine and junctional layers. The placentas of pregnant women with GDM showed reduced expression of AnxA1 in the villous compartment, increased DNA damage, apoptosis, and a reduction of enzymes involved in the BER pathway. Our translational data provide valuable insights into the possible involvement of ANXA1 in the response of placental cells to oxidative DNA damage and represent an advancement in investigations into the mechanisms involved in placental biology.

ANNEXIN A1: Roles in Placenta, Cell Survival, and Nucleus.

The unbiased approaches of the last decade have enabled the collection of new data on the biology of annexin A1 (ANXA1) in a variety of scientific aspects, creating opportunities for new biomarkers and/or therapeutic purposes. ANXA1 is found in the plasma membrane, cytoplasm, and nucleus, being described at low levels in the nuclear and cytoplasmic compartments of placental cells related to gestational diabetic diseases, and its translocation from the cytoplasm to the nucleus has been associated with a response to DNA damage. The approaches presented here open pathways for reflection upon, and intrinsic clarification of, the modulating action of this protein in the response to genetic material damage, as well as its level of expression and cellular localization. The objective of this study is to arouse interest, with an emphasis on the mechanisms of nuclear translocation of ANXA1, which remain underexplored and may be beneficial in new inflammatory therapies.

Effect of Piper cubeba total extract and isolated lignans on head and neck cancer cell lines and normal fibroblasts.

The objective of the present study was to evaluate the action of the crude hydroalcoholic extract of Piper cubeba fruits and isolated lignans (cubebin, dihydrocubebin, ethylcubebin, hinokinin and methylcubebin) on head and neck cancer cells. We evaluated the influence of the Piper cubeba extract and isolated lignans (10, 50 e 100 µg/mL) for 4, 24, 48 and 72 h, in the larynx (Hep-2) and oral (SCC-25) squamous cell carcinoma cells and normal fibroblasts, on morphology, cell proliferation and migration, cytotoxicity, genotoxicity and gene and protein expression (PTGS2, PTGER3, PTGER4, MMP2, MMP9). The results showed that the P. cubeba extract and different lignans do not alter the cellular morphology, but decrease cell proliferation and migration, have low cytotoxic and genotoxic effects, probably due to the alteration of the expression of genes and proteins involved with inflammatory process. From these data, we can conclude that the lignans cubebin and methylcubebin had a greater effect on head and neck cancer cells in the antiproliferative, antimigratory and genotoxic action, and could be the target of the development of new therapies including possible new drugs as a therapeutic resource for the treatment of head and neck cancer due to its immense range of biological properties.

Annexin A1 Mimetic Peptide and Piperlongumine: Anti-Inflammatory Profiles in Endotoxin-Induced Uveitis.

Uveitis is one of the main causes of blindness worldwide, and therapeutic alternatives are worthy of study. We investigated the effects of piperlongumine (PL) and/or annexin A1 (AnxA1) mimetic peptide Ac2-26 on endotoxin-induced uveitis (EIU). Rats were inoculated with lipopolysaccharide (LPS) and intraperitoneally treated with Ac2-26 (200 µg), PL (200 and 400 µg), or Ac2-26 + PL after 15 min. Then, 24 h after LPS inoculation, leukocytes in aqueous humor, mononuclear cells, AnxA1, formyl peptide receptor (fpr)1, fpr2, and cyclooxygenase (COX)-2 were evaluated in the ocular tissues, along with inflammatory mediators in the blood and macerated supernatant. Decreased leukocyte influx, levels of inflammatory mediators, and COX-2 expression confirmed the anti-inflammatory actions of the peptide and pointed to the protective effects of PL at higher dosage. However, when PL and Ac2-26 were administered in combination, the inflammatory potential was lost. AnxA1 expression was elevated among groups treated with PL or Ac2-26 + PL but reduced after treatment with Ac2-26. Fpr2 expression was increased only in untreated EIU and Ac2-26 groups. The interaction between Ac2-26 and PL negatively affected the anti-inflammatory action of Ac2-26 or PL. We emphasize that the anti-inflammatory effects of PL can be used as a therapeutic strategy to protect against uveitis.

Protective effects of piperlongumin in the prevention of inflammatory damage caused by pulmonary exposure to benzopyrene carcinogen.

Benzopyrene is one of the main polycyclic aromatic hydrocarbons with carcinogenic capacity. Research has shown that anti-inflammatory drugs can reduce the incidence of lung cancer. In this scenario, we highlight piperlongumin (PL), an alkaloid from Piper longum with anti-inflammatory properties. Therefore, our aim was to study the effect of PL administration in a model of pulmonary carcinogenesis induced by benzopyrene in Balb/c mice. Animals were divided into 3 groups (n = 10/group): sham (10% DMSO), induced by benzopyrene (100 mg/kg, diluted in DMSO) without treatment (BaP) for 12 weeks and induced by benzopyrene and treated with PL (BaP/PL) (2 mg/kg in 10% DMSO) from the eighth week post-induction. Animals were weighed daily and pletsmography was performed in the 12th week. Genotoxicity and hemoglobin levels were analyzed in blood and quantification of leukocytes in bronchoalveolar lavage (BAL). Lungs were collected for histopathological evaluation, immunohistochemical studies of annexin A1 (AnxA1), cyclooxygenase 2 (COX-2), anti-apoptotic protein Bcl-2 and nuclear transcription factor (NF-kB) and also the measurement of interleukin cytokines (IL)-1ß, IL-17 and tumor necrosis factor (TNF) -α. Treatment with PL reduced the pulmonary parameters (p < 0,001) of frequency, volume and pulmonary ventilation, decreased lymphocytes, monocytes and neutrophils in BAL (p < 0,05) as well as blood hemoglobin levels (p < 0,01). PL administration also reduced DNA damage and preserved the pulmonary architecture compared to the BaP group. Moreover, the anti-inflammatory effect of PL was evidenced by the maintenance of AnxA1 levels, reduction of COX-2 (p < 0,05), Bcl-2 (p < 0,01) and NF-kB (p < 0,001) expressions and decreased IL-1ß, IL-17 (p < 0,01) and TNF-α (p < 0,05) levels. The results show the therapeutic potential of PL in the treatment of pulmonary anti-inflammatory and anti-tumor diseases with promising therapeutic implications.

Formyl Peptide Receptors and Annexin A1: Complementary Mechanisms to Infliximab in Murine Experimental Colitis and Crohn's Disease.

Non-responsiveness to anti-TNF-α therapies presents relevant rates in inflammatory bowel disease patients, presenting the need to find biomarkers involved in therapeutic efficacy. Herein, we demonstrate that higher levels of colonic formyl peptide receptor 1 and annexin A1 correlate with histological recovery in Crohn's disease patients under remission. Using the dextran sulfate sodium colitis model in mice, we suggest that infliximab induces annexin A1 expression and secretion in activated intestinal leukocytes. Conversely, this mechanism might stimulate epithelial formyl peptide receptors, inducing wound healing and consequent histological remission. Our data indicate that assessing intestinal expressions of formyl peptide receptors and annexin A1 might provide precious information on the disease activity and responsiveness to infliximab in inflammatory bowel disease patients.

Annexin A1 Mimetic Peptide Ac2-26 Modulates the Function of Murine Colonic and Human Mast Cells.

Mast cells (MCs) are main effector cells in allergic inflammation and after activation, they release stored (histamine, heparin, proteases) and newly synthesized (lipid mediators and cytokines) substances. In the gastrointestinal tract the largest MC population is located in the lamina propria and submucosa whereas several signals such as the cytokine IL-4, seem to increase the granule content and to stimulate a remarkable expansion of intestinal MCs. The broad range of MC-derived bioactive molecules may explain their involvement in many different allergic disorders of the gastrointestinal tract. Annexin A1 (AnxA1) is a 37 KDa glucocorticoid induced monomeric protein selectively distributed in certain tissues. Its activity can be reproduced by mimetic peptides of the N-terminal portion, such as Ac2-26, that share the same receptor FPR-L1. Although previous reports demonstrated that AnxA1 inhibits MC degranulation in murine models, the effects of exogenous peptide Ac2-26 on intestinal MCs or the biological functions of the Ac2-26/FPR2 system in human MCs have been poorly studied. To determine the effects of Ac2-26 on the function of MCs toward the possibility of AnxA1-based therapeutics, we treated WT and IL-4 knockout mice with peptide Ac2-26, and we examined the spontaneous and compound 48/80 stimulated colonic MC degranulation and cytokine production. Moreover, in vitro, using human mast cell line HMC-1 we demonstrated that exogenous AnxA1 peptide is capable of interfering with the HMC-1 degranulation in a direct pathway through formyl peptide receptors (FPRs). We envisage that our results can provide therapeutic strategies to reduce the release of MC mediators in inflammatory allergic processes.

Hydrogen peroxide and Helicobacter pylori extract treatment combined with APE1 knockdown induce DNA damage, G2/M arrest and cell death in gastric cancer cell line.

Chronic inflammation resulting from Helicobacter pylori (H. pylori) infection, the major risk factor for gastric cancer, results in increased release of reactive oxygen species (ROS), promoting oxidative stress and DNA damage. APE1 endonuclease, a key component of the base excision repair (BER) pathway, is responsible for the repair of damage induced by ROS. However, the APE1 gene and other DNA damage response (DDR) genes are still poorly understood in gastric cancer. Thus, we aimed to investigate whether the silencing of APE1 by shRNA can interfere with the survival of AGS gastric cancer cells after treatment with hydrogen peroxide (H2O2) and/or H. pylori extract (HPE) and its relation with the expression of DDR genes (ATM, ATR, and H2AX) and miRNAs that target DDR genes. In the AGS cells expressing APE1, isolated or combined treatment with H2O2 and HPE promoted a slight increase in the cell proliferation and increased the levels of intracellular ROS and DNA double strand breaks (DSBs) indicated by ©H2AX foci, a reduction in the proportion of cells in the G0/G1 phase and an increase in the initial apoptosis rate. Moreover, upregulation of APE1, ATR, miR-15a, miR-21, miR-24 and miR-421 and downregulation of ATM and H2AX was observed. In silenced AGS cells after treatment with H2O2 alone or combined with HPE, we observed an increase in the cell proliferation rate and the levels of intracellular ROS and DSBs and a reduction in the proportion of cells in S and G2/M phase arrest, leading to late apoptosis. APE1 knockdown also caused a reduction in the expression of ATM and miR-421, while ATR expression was increased. Based on our results, APE1 knockdown may promote changes in cellular processes by increasing genomic instability, leading to G2/M arrest and cell apoptosis, so it may be a promising strategy for controlling tumor progression.

Cisplatin treatment modulates Annexin A1 and inhibitor of differentiation to DNA 1 expression in cervical cancer cells.

Cisplatin (Cis) is a choice chemotherapy approach to cervical cancer by inducing DNA adducts and subsequent apoptosis. We have investigated the effects of Cis on Annexin A1 (ANXA1) and inhibitor of DNA binding 1 (ID1) proteins expression to elucidate further mechanisms of Cis actions. Human cervical tissue samples from twenty-four patients, with Cervical Intraepithelial Neoplasia (CIN, stage I, II and III), were evaluated to quantified ANXA1 and ID1 expressions. In vitro, human epidermoid carcinoma of the cervix (SiHa cell line) were treated with Annexin A1 peptide (ANXA12-26), Cis or Cis + ANXA12-26 to evaluate cell proliferation and migration, cytotoxicity of treatments as well as ANXA1 and ID1 modulations by mRNA and protein expression. Our findings showed expression of ID1 and ANXA1 proteins in tissue samples from Cervical Intraepithelial Neoplasia (CIN) patients, with intense immunological identification of ID1 in the CIN III stage. In SiHa cells, treatments with Cis alone or Cis + ANXA12-26, increase mRNA expressions of the ANXA1 and reduced the ID1. In agreement, Cis + ANXA12-26 enhanced ANXA1 protein expression and Cis or Cis + ANXA12-26 abolished ID1 protein expression. Cell proliferation was reduced after treatment with ANXA12-26 peptide and more significant after Cis or Cis + ANXA12-26 treatments. These two last treatments reduced cell viability, by inducing late apoptosis, and impaired cell migration. Together, our data highlight endogenous ANXA1 is involved in Cis therapy for cervical cancer.

The involvement of annexin A1 in human placental response to maternal Zika virus infection.

The association of Zika virus infection (ZIKV) with congenital malformation and neurological sequelae brought a significant global concern. Recent studies have shown that maternal viral infection leads to inflammation in the placental tissue. In this context, the antiinflammatory protein annexin 1 (ANXA1) has a major determination of the resolution of inflammation and it has been positively associated with antiparasitic activity in infected placental explants. Although these effects have been explored to some degree, ANXA1 expression and potential properties have not yet been fully elucidated in placentas infected with ZIKV. This study was conducted to evaluate the histopathology, inflammatory process and elucidate if ANXA1 were differently expressed in placentas of ZIKV-infected mothers. Three classification groups were used in this study: Neg/Neg (mother and placenta negative for the virus), Pos/Neg (infected mother, but no virus detected in placenta) and Pos/Pos (mother and placenta infected with ZIKV). ANXA1 was expressed in syncytiotrophoblast cells of all studied groups, and its expression was decreased in Pos/Neg group, which displayed also an increase of the inflammatory response, as evinced from the recruitment of inflammatory cells, increased levels of placenta cytokines, and evidence of impaired tissue repair. The presence of ZIKV in placentas of Pos/Pos group shows structural alterations, including detachment and disorganization of the trophoblastic epithelium. In summary, our results suggest that maternal infection with ZIKV, even without direct tissue infection, leads to a placental inflammatory response probably related to the modulation of ANXA1. After placental infection, structural changes - including inflammatory cells influx - are observed leading to placental dysfunction and reduced fetal weight. Our study sheds additional light on the outcomes of ZIKV infection in trophoblast and reveals a potential involvement of ANXA1 in the placental biology.

Annexin A1 Regulates NLRP3 Inflammasome Activation and Modifies Lipid Release Profile in Isolated Peritoneal Macrophages.

Annexin A1 (AnxA1) is a potent anti-inflammatory protein that downregulates proinflammatory cytokine release. This study evaluated the role of AnxA1 in the regulation of NLRP3 inflammasome activation and lipid release by starch-elicited murine peritoneal macrophages. C57bl/6 wild-type (WT) and AnxA1-null (AnxA1-/-) mice received an intraperitoneal injection of 1.5% starch solution for macrophage recruitment. NLRP3 was activated by priming cells with lipopolysaccharide for 3 h, followed by nigericin (1 h) or ATP (30 min) incubation. As expected, nigericin and ATP administration decreased elicited peritoneal macrophage viability and induced IL-1ß release, more pronounced in the AnxA1-/- cells than in the control peritoneal macrophages. In addition, nigericin-activated AnxA1-/- macrophages showed increased levels of NLRP3, while points of co-localization of the AnxA1 protein and NLRP3 inflammasome were detected in WT cells, as demonstrated by ultrastructural analysis. The lipidomic analysis showed a pronounced release of prostaglandins in nigericin-stimulated WT peritoneal macrophages, while ceramides were detected in AnxA1-/- cell supernatants. Different eicosanoid profiles were detected for both genotypes, and our results suggest that endogenous AnxA1 regulates the NLRP3-derived IL-1ß and lipid mediator release in macrophages.

Involvement of the annexin A1-Fpr anti-inflammatory system in the ocular allergy.

Annexin A1 (ANXA1)-formyl peptide receptor (Fpr) system is potent effective mediators in the control of the inflammatory response. In this study, we evaluate the potential involvement of the Fpr family in the protective effect of the mimetic peptide of ANXA1 (ANXA12-26) using an experimental allergic conjunctivitis (AC) model in mice. Ovalbumin (OVA)/Alum-immunized wild-type (WT) and ANXA1-null (ANXA1-/-) Balb/c mice (days 0 and 7) were challenged by eye drops containing OVA on days 14-16, and two groups received ANXA12-26 alone or with Fpr antagonist Boc2 intraperitoneally during challenged days. As expected, plasma IgE anti-OVA levels increased significantly in the OVA-immunized WT and ANXA1-/- mice, supporting the efficacy of AC model. AC increased Fpr1 and Fpr2 levels in the conjunctiva and the lack of endogenous ANXA1 exacerbated Fpr2 expression only. In contrast, administering ANXA12-26 in the WT mice diminished Fpr2 levels in the conjunctiva, and the effect was reverted by Boc2. Ultrastructural analysis showed the co-localization of Fpr2 and ANXA1 in the plasma membrane of mast cells (MCs), eosinophils and neutrophils, supporting this system as being operative in the AC. Boc2 abrogated the ANXA12-26 effect by increasing the MC degranulation and the eosinophil influx in the conjunctiva, and these findings were supported by peroxidase eosinophil, eotaxin and MC protease levels. Additionally, the ANXA12-26-Fpr system in the AC was associated with the activation of ERK and JNK. Collectively, the data provided in vivo supports the anti-allergic effects of the ANXA1-Fpr system and may serve as a therapeutic target in this ocular disorder.

Annexin A12-26 Treatment Improves Skin Heterologous Transplantation by Modulating Inflammation and Angiogenesis Processes.

Skin graft successful depends on reduction of local inflammation evoked by the surgical lesion and efficient neovascularization to nutrition the graft. It has been shown that N-terminal portion of the Annexin A1 protein (AnxA1) with its anti-inflammatory properties induces epithelial mucosa repair and presents potential therapeutic approaches. The role of AnxA1 on wound healing has not been explored and we investigated in this study the effect of the peptide Ac2-26 (N-terminal AnxA1 peptide Ac2-26; AnxA12-26) on heterologous skin scaffolds transplantation in BALB/c mice, focusing on inflammation and angiogenesis. Treatment with AnxA12-26, once a day, from day 3-60 after scaffold implantation improved the take of the implant, induced vessels formation, enhanced gene and protein levels of the vascular growth factor-A (VEGF-A) and fibroblast influx into allograft tissue. It also decreased pro- while increasing anti-inflammatory cytokines. The pro-angiogenic activity of AnxA12-26 was corroborated by topical application of AnxA12-26 on the subcutaneous tissue of mice. Moreover, treatment of human umbilical endothelial cells (HUVECs) with AnxA12-26 improved proliferation, shortened cycle, increased migration and actin polymerization similarly to those evoked by VEGF-A. The peptide treatment instead only potentiated the tube formation induced by VEGF-A. Collectively, our data showed that AnxA12-26 treatment favors the tissue regeneration after skin grafting by avoiding exacerbated inflammation and improving the angiogenesis process.

Annexin A1 peptide is able to induce an anti-parasitic effect in human placental explants infected by Toxoplasma gondii.

This study was conducted to investigate annexin A1 (ANXA1) functions in human placental explants infected with Toxoplasma gondii (T. gondii). We examined the first and third trimester placental explants infected with T. gondii (n = 7 placentas/group) to identify the number and location of parasites, ANXA1 protein, potential involvement of formyl peptide receptors (FPR1 and FPR2), and COX-2 expressions by immunohistochemistry. Treatments with Ac2-26 mimetic peptide of ANXA1 were performed to verify the parasitism rate (ß-galactosidase assay), prostaglandin E2 levels (ELISA assay), and ANXA1, FPR1 and COX-2 expression in third trimester placentas. Placental explants of third trimester expressed less ANXA1 and were more permissive to T. gondii infection than first trimester placentas that expressed more ANXA1. Ac2-26 treatment increases endogenous ANXA1 and decreases parasitism rate, COX-2, and prostaglandin E2 levels. Altogether, these data provide further insight into the anti-parasitic and anti-inflammatory effects of ANXA1 in placentas infected with T. gondii.

Zika-virus-infected human full-term placental explants display pro-inflammatory responses and undergo apoptosis.

Zika virus (ZIKV) is a flavivirus that has been highly correlated with the development of neurological disorders and other malformations in newborns and stillborn fetuses after congenital infection. This association is supported by the presence of ZIKV in the fetal brain and amniotic fluid, and findings suggest that infection of the placental barrier is a critical step for fetal ZIKV infection in utero. Therefore, relevant models to investigate the interaction between ZIKV and placental tissues are essential for understanding the pathogenesis of Zika syndrome. In this report, we demonstrate that explant tissue from full-term human placentas sustains a productive ZIKV infection, though the results depend on the strain. Viral infection was found to be associated with pro-inflammatory cytokine expression and apoptosis of the infected tissue, and these findings confirm that placental explants are targets of ZIKV replication. We propose that human placental explants are useful as a model for studying ZIKV infection ex vivo.

Treatment with galectin-1 eye drops regulates mast cell degranulation and attenuates the severity of conjunctivitis.

Galectin-1 (Gal-1) is a ß-galactoside-binding protein with diverse biological activities in the pathogenesis of inflammation, however the mechanisms by which Gal-1 modulates cellular responses in allergic inflammatory processes have not been fully determined. In this study, we evaluated the therapeutic potential of Gal-1 eye drops in an experimental model of conjunctivitis. Wistar rats received a topical application of compound (C)48/80 (100 mg/ml) into right eyes and a drop of vehicle into the contralateral eye. Another group of rats received Gal-1 (0.3 or 3 µg/eye) or sodium cromoglycate (SCG; 40 mg/ml) in both eyes and, after 15 min, right eye was challenged with C48/80. Conjunctivitis-induced by C48/80 was characterized by severe eyelid oedema and tearing, but clinical signs were ameliorated by eye drop doses of both Gal-1 (0.3/3 µg) and SCG. As expected, an increased proportion of degranulated mast cells (62%, P < 0.01) and lower histamine levels were observed after 6 h of C48/80 challenge, compared to control (32%). This effect was abrogated by Gal-1 and SCG, which reduced mast cell degranulation (31-36%), eosinophil migration and eosinophil peroxidase levels in the eyes. Gal-1 (3 µg) and SCG treatments also decreased IL-4 levels, as well as activation of mitogen activated protein kinases compared to untreated C48/80 eyes. Our findings suggest that Gal-1 eye drops represent a new therapeutic strategy for ocular allergic inflammation.

Heterogeneity of mast cells and expression of Annexin A1 protein in a second degree burn model with silver sulfadiazine treatment.

Mast cells (MCs) participate in all stages of skin healing and one of their mediators is the Annexin A1 protein (AnxA1), linked to inflammation, proliferation, migration and apoptosis processes, but not studied in thermal burns yet. Therefore, our objectives were to evaluate the behavior of MCs and AnxA1 in a second degree burn model, treated or not with silver sulfadiazine 1% (SDP 1%) and associated to macrophages quantification and cytokines dosages. MCs counts showed few cells in the early stages of repair but increased MCs in the final phases in the untreated group. The normal skin presented numerous tryptase-positive MCs that were reduced after burning in all analyzed periods. Differently, few chymase-positive MCs were observed in the early stages of healing, however, increased chymase-positive MCs were found at the final phase in the untreated group. MCs also showed high immunoreactivity for AnxA1 on day 3 in both groups. In the tissue there was a strong protein expression in the early stages of healing, but in the final phases only in the SDP treated animals. TNF-α, IL-1ß, IL-6, IL-10 and MCP-1 levels and macrophages quantification were increased in inflammation and reepithelialization phases. Reduced IL-1ß, IL-6 and IL-10 levels and numerous macrophages occurred in the treated animals during tissue repair. Our results indicate modulation in the profile of MCs and AnxA1expression during healing by the treatment with SDP 1%, pointing them as targets for therapeutic interventions on skin burns.

ANXA1Ac2-26 peptide, a possible therapeutic approach in inflammatory ocular diseases.

The eye is immunologically privileged when inflammatory responses are suppressed. One component responsible for the suppression of inflammatory responses is the blood retinal barrier, which comprises the retinal pigment epithelium. The destruction of this barrier initiates inflammation, which can affect any part of the eye. Therefore, inflammatory response is controlled by the action of anti-inflammatory mediators, among these mediators, annexin A1 (ANXA1) protein acts as a modulator of inflammation. In this study we aimed to improve the knowledge of this area by investigating how a peptide of the ANXA1 protein (ANXA1Ac2-26) modulates the morphology, proliferation, migration and expression of genes and proteins in human retinal pigment epithelium cells (ARPE-19). Determining how signaling pathways (NF-κB and UBC) are modulated by the ANXA1Ac2-26 peptide could be important for understanding the inflammatory process. ARPE-19 cells were activated by bacterial lipopolysaccharide endotoxin (LPS) and treated with ANXA1Ac2-26 peptide, in a concentration of 1.7µM and 33.8µM. We observed that the LPS activation diminished the levels of endogenous ANXA1 after 2h and 24h and ANXA1Ac2-26 peptide decreased the proliferation and re-establishes the migration of ARPE-19 cells. After using a hybridization approach, 80 differentially expressed genes were found. Five of these genes were selected (LRAT, CTGF, MAP1B, ALDH1A3 and SETD7) and all were down-regulated after treatment with the peptide. The genes CTGF and LRAT would be considered as potential molecular markers of ophthalmologic inflammation. The expression of pro-inflammatory cytokines was also decreased after the treatment, indicating the efficiency of the anti-inflammatory peptide at high concentrations, since the reduction in the levels of these mediators were observed after the treatment with ANXA1Ac2-26 peptide at 33.8µM. Our results suggest that the retinal pigment epithelial cells are a potential target of the ANXA1 protein and point to possible applications of the ANXA1Ac2-26 peptide as an innovative therapy for the treatment of ocular inflammation.