ICAM-1 and IL-8 are expressed by DEHP and suppressed by curcumin through ERK and p38 MAPK in human umbilical vein endothelial cells

Thyroid dysfunction caused by exposure to environmental endocrine disruptors and the underlying mechanism: A review

Thyroid disease has been rapidly increasing, but its causes remain unclear. At present, many studies have focused on the relationship between environmental endocrine disruptors (EEDs) and the pathogenesis of thyroid disease. Herein, we summarize such studies exploring the effects of exposure to common EEDs on thyrotoxicosis, finding that EEDs appear to contribute to the pathogenesis of thyroid-related diseases such as thyroid cancer, goiter, thyroiditis, hyperthyroidism, and hypothyroidism. To explore this causative effect in detail, we have analyzed the following three aspects of how EEDs are believed to exert their impacts on the occurrence and development of thyroid disease: (1) damage to the thyroid tissue structure, including disrupted mitochondria and the stratification of thyroid follicular epithelial cells; (2) disruption of thyroid hormone signaling, including thyroid hormone synthesis and secretion disorders, destruction of normal function of the hypothalamus-pituitary-thyroid axis, disturbed estrogen signaling in the body, alterations to the level of thyroid-stimulating hormone, inhibition of the release of thyroglobulin from thyroid cells, and reductions in the levels of sodium iodide co-transporters, thyroid peroxidase, deiodinase, and transthyretin; and (3) molecular mechanisms underlying the disruption of thyroid function, including competitive binding to T3 and T4 receptors, disturbance of the hypothalamic-pituitary-thyroid axis, activation of the ERK and Akt pathways, oxidative stress, regulation of the expression of the proto-oncogene k-Ras, tumor suppressor gene PTEN, and thyroid TSHR gene, and induction of autophagy in thyroid cells. Overall, this article reviews how EEDs can affect the occurrence and development of thyroid disease via multiple routes, thus providing new ideas to intervene for the prevention, diagnosis, treatment, and prognosis of thyroid disease.

Cross-sectional associations between phthalates, phenols, and parabens with metabolic syndrome risk during early-to-mid adolescence among a cohort of Mexican youth

BACKGROUND

Epidemiological studies on children and adults have linked toxicants from plastics and personal care products to metabolic disruption. Yet, the impact of endocrine-disrupting chemicals (EDCs) on adolescent metabolic syndrome (MetS) risk during early and mid-adolescence is unclear.

METHODS

To examine the links between exposure to EDCs and MetS risk and its components, cross-sectional data from 344 Mexican youth in early-to-mid adolescence (10-17 years) were analyzed. Urinary biomarker concentrations of phthalates, phenol, and paraben analytes were measured from a single spot urine sample collected in 2015; study personnel obtained anthropometric and metabolic measures. We examined associations between summary phthalates and metabolites, phenol, and paraben analytes with MetS risk z-scores using linear regression, adjusted for specific gravity, sex, age, pubertal status, smoking, alcohol intake, physical activity level, and screen time. As a secondary aim, mediation analysis was conducted to evaluate the role of hormones in the association between summary phthalates with lipids and MetS risk z-scores.

RESULTS

The mean (SD) age was 13.2 (1.9) years, and 50.9% were female. Sex-stratified analyses revealed associations between summary phthalates and lipids ratio z-scores, including Σ DEHP [β = 0.21 (95% CI: 0.04, 0.37; p < 0.01)], phthalates from plastic sources (Σ Plastic) [β = 0.22 (95% CI: 0.05, 0.39; p < 0.01)], anti-androgenic phthalates (Σ AA) [β = 0.22 (95% CI: 0.05, 0.39; p < 0.01)], and individual phthalate metabolites (MEHHP, MEOHP, and MECPP) among males. Among females, BPA [β = 0.24 (95% CI: 0.03, 0.44; p < 0.05)] was positively associated with lipids ratio z-score and one phenol (2,5 DCP) [β = 0.09 (95% CI: 0.01, 0.18); p < 0.05)] was associated with increased waist circumference z-score. Results showed no evidence of mediation by hormone concentrations in the association between summary phthalates with lipids ratio or MetS risk z-scores.

CONCLUSION

Higher EDC exposure was positively associated with serum lipids during adolescence, particularly among males.

Prenatal DEHP Exposure Induces Premature Testicular Aging by Promoting Leydig Cell Senescence through the MAPK Signaling Pathways

Previous studies show that prenatal di-(2-ethylhexyl) phthalate (DEHP) exposure induces premature testicular aging. However, the evidence is weak, and the underlying mechanisms remain unclear. p38/extracellular signal-regulated kinase (ERK)/c-Jun NH(2)-terminal kinase (JNK) MAPK pathways participate in aging. Leydig cell (LC) senescence results in testicular aging. Whether prenatal DEHP exposure induces premature testicular aging by promoting LC senescence warrants further study. Here, male mice undergo prenatal exposure to 500 mg per kg per day DEHP, and TM3 LCs are treated with 200 µm mono (2-ethylhexyl) phthalate (MEHP). MAPK pathways, testicular toxicity, and senescent phenotypes (β-gal activity, p21, p16, and cell cycle) of male mice and LCs are explored. Prenatal DEHP exposure induces premature testicular aging in middle-aged mice (poor genital development, reduced testosterone synthesis, poor semen quality, increased β-gal activity, and upregulated expression of p21 and p16). MEHP induces LCs senescence (cell cycle arrest, increased β-gal activity, and upregulated expression of p21). p38 and JNK pathways are activated, and the ERK pathway is inactivated. In conclusion, prenatal DEHP exposure induces premature testicular aging by promoting LC senescence through MAPK signaling pathways.

Adverse cardiovascular effects and potential molecular mechanisms of DEHP and its metabolites-A review

Currently, cardiovascular disease (CVD) is a health hazard that is associated with progressive deterioration upon exposure to environmental pollutants. Di(2-ethylhexyl) phthalate (DEHP) has been one of the focuses of emerging concern due to its ubiquitous nature and its toxicity to the cardiovascular (CV) system. DEHP has been noted as a causative risk factor or a risk indicator for the initiation and augment of CVDs. DEHP represents a precursor that contributes to the pathogenesis of CVDs through its active metabolites, which mainly include mono (2-ethylhexyl) phthalate (MEHP). Herein, we systematically presented the association between DEHP and its metabolites and adverse CV outcomes and discussed the corresponding effects, underlying mechanisms and possibly interventions. Epidemiological and experimental evidence has suggested that DEHP and its metabolites have significant impacts on processes and factors involved in CVD, such as cardiac developmental toxicity, cardiac injury and apoptosis, cardiac arrhythmogenesis, cardiac metabolic disorders, vascular structural damage, atherogenesis, coronary heart disease and hypertension. DNA methylation, PPAR-related pathways, oxidative stress and inflammation, Ca²⁺ homeostasis disturbance may pinpoint the relevant mechanisms. The preventive and therapeutic measures are potentially related with P-glycoprotein, heat-shock proteins, some antioxidants, curcumin, apigenin, β-thujaplicin, glucagon-like peptide-1 receptor agonists and Ang-converting enzyme inhibitors and so on. Promisingly, future investigations should aid in thoroughly assessing the causal relationship and molecular interactions between CVD and DEHP and its metabolites and explore feasible prevention and treatment measures accordingly.

An Investigation for Skin Tissue Regeneration Enhancement/Augmentation by Curcumin-Loaded Self-Emulsifying Drug Delivery System (SEDDS)

Diabetes, one of the global metabolic disorders, is often associated with delayed wound healing due to the elevated level of free radicals at the wound site, which hampers skin regeneration. This study aimed at developing a curcumin-loaded self-emulsifying drug delivery system (SEDDS) for diabetic wound healing and skin tissue regeneration. For this purpose, various curcumin-loaded SEDDS formulations were prepared and optimized. Then, the SEDDS formulations were characterized by the emulsion droplet size, surface charge, drug content/entrapment efficiency, drug release, and stability. In vitro, the formulations were assessed for the cellular uptake, cytotoxicity, cell migration, and inhibition of the intracellular ROS production in the NIH3T3 fibroblasts. In vivo, the formulations' wound healing and skin regeneration potential were evaluated on the induced diabetic rats. The results indicated that, after being dispersed in the aqueous medium, the optimized SEDDS formulation was readily emulsified and formed a homogenous dispersion with a droplet size of 37.29 ± 3.47 nm, surface charge of -20.75 ± 0.07 mV, and PDI value of less than 0.3. The drug content in the optimized formulation was found to be 70.51% ± 2.31%, with an encapsulation efficiency of 87.36% ± 0.61%. The SEDDS showed a delayed drug release pattern compared to the pure drug solution, and the drug release rate followed the Fickian diffusion kinetically. In the cell culture, the formulations showed lower cytotoxicity, higher cellular uptake, and increased ROS production inhibition, and promoted the cell migration in the scratch assay compared to the pure drug. The in vivo data indicated that the curcumin-loaded SEDDS-treated diabetic rats had significantly faster-wound healing and re-epithelialization compared with the untreated and pure drug-treated groups. Our findings in this work suggest that the curcumin-loaded SEDDS might have great potential in facilitating diabetic wound healing and skin tissue regeneration.

Vascular Protective Effect and Its Possible Mechanism of Action on Selected Active Phytocompounds: A Review

Vascular endothelial dysfunction is characterized by an imbalance of vasodilation and vasoconstriction, deficiency of nitric oxide (NO) bioavailability and elevated reactive oxygen species (ROS), and proinflammatory factors. This dysfunction is a key to the early pathological development of major cardiovascular diseases including hypertension, atherosclerosis, and diabetes. Therefore, modulation of the vascular endothelium is considered an important therapeutic strategy to maintain the health of the cardiovascular system. Epidemiological studies have shown that regular consumption of medicinal plants, fruits, and vegetables promotes vascular health, lowering the risk of cardiovascular diseases. This is mainly attributed to the phytochemical compounds contained in these resources. Various databases, including Google Scholar, MEDLINE, PubMed, and the Directory of Open Access Journals, were searched to identify studies demonstrating the vascular protective effects of phytochemical compounds. The literature had revealed abundant data on phytochemical compounds protecting and improving the vascular system. Of the numerous compounds reported, curcumin, resveratrol, cyanidin-3-glucoside, berberine, epigallocatechin-3-gallate, and quercetin are discussed in this review to provide recent information on their vascular protective mechanisms in vivo and in vitro. Phytochemical compounds are promising therapeutic agents for vascular dysfunction due to their antioxidative mechanisms. However, future human studies will be necessary to confirm the clinical effects of these vascular protective mechanisms.

Endocrine disrupting chemicals: Friend or foe to brown and beige adipose tissue?

The effects of Endocrine Disrupting Chemicals (EDCs) on the current obesity epidemic is a growing field of interest. Numerous EDCs have shown the potential to alter energy metabolism, which may increase the risk of obesity, in part, through direct actions on adipose tissue. While white adipose tissue has historically been the primary focus of this work, evidence of the EDC-induced disruption of brown and beige adipose tissues continues to build. Both brown and beige fat are thermogenic adipose depots rich in mitochondria that dispense heat when activated. Due to these properties, brown and beige fat are implicated in metabolic diseases such as obesity, diabetes, and cachexia. This review delves into the current literature of different EDCs, including bisphenols, dioxins, air pollutants, phthalates, and phytochemicals. The possible implications that these EDCs have on thermogenic adipose tissues are covered. This review also introduces the possibility of using brown and beige fat as a therapeutic target organ by taking advantage of some of the properties of EDCs. Collectively, we provide a comprehensive discussion of the evidence of EDC disruption in white, brown, and beige fat and highlight gaps worthy of further exploration.

Phenolic Compounds Exerting Lipid-Regulatory, Anti-Inflammatory and Epigenetic Effects as Complementary Treatments in Cardiovascular Diseases

Atherosclerosis is the main process behind cardiovascular diseases (CVD), maladies which continue to be responsible for up to 70% of death worldwide. Despite the ongoing development of new and potent drugs, their incomplete efficacy, partial intolerance and numerous side effects make the search for new alternatives worthwhile. The focus of the scientific world turned to the potential of natural active compounds to prevent and treat CVD. Essential for effective prevention or treatment based on phytochemicals is to know their mechanisms of action according to their bioavailability and dosage. The present review is focused on the latest data about phenolic compounds and aims to collect and correlate the reliable existing knowledge concerning their molecular mechanisms of action to counteract important risk factors that contribute to the initiation and development of atherosclerosis: dyslipidemia, and oxidative and inflammatory-stress. The selection of phenolic compounds was made to prove their multiple benefic effects and endorse them as CVD remedies, complementary to allopathic drugs. The review also highlights some aspects that still need clear scientific explanations and draws up some new molecular approaches to validate phenolic compounds for CVD complementary therapy in the near future.

Curcumin Preparations Can Improve Flow-Mediated Dilation and Endothelial Function: A Meta-Analysis

INTRODUCTION

Endothelial dysfunction is an early marker of atherosclerosis. Flow-mediated dilation (FMD), measured by ultrasonography, is used to noninvasively assess endothelial dysfunction. Preparations of curcumin, a naturally occurring pigment found in turmeric, may improve FMD and thus endothelial dysfunction. We did a systematic review and meta-analysis to analyze the effect of curcumin preparations on endothelial dysfunction.

METHODS

Five randomized clinical trials met the inclusion criteria for meta-analysis. The primary outcome was an improvement in FMD, as measured at brachial artery, after supplementations with curcumin preparations compared to the control group. Standardized mean difference and Hedges' g were used for effect size (ES) measurement. An ES of 0.2-0.5 is considered small, 0.5-0.8 is medium, and more than 0.8 is large. Publication bias was studied too.

RESULTS

We found supplementation with curcumin preparations had an overall ES (standard difference in means) of 1.379 (95% CI 0.485-2.274, p = 0.003) on FMD. The overall Hedges' g was 1.353 (95% CI 0.47-2.235, p = 0.03). This analysis suggests a positive and large ES of curcumin preparations on FMD using a random effect model. Smokers had a smaller increase in FMD compared to nonsmokers (ES 0.379 vs. 1.639, p = 0.034).

CONCLUSION

This meta-analysis of 5 randomized clinical trials indicates a significant effect of curcumin preparations to increase the FMD compared to placebo and thus endothelial function. This effect is not strongly noticed in smokers.

Curcumin modulates chronic myelogenous leukemia exosomes composition and affects angiogenic phenotype via exosomal miR-21

Tumor derived exosomes are vesicles which contain proteins and microRNAs that mediate cell-cell communication and are involved in angiogenesis and tumor progression. Curcumin derived from the plant Curcuma longa, shows anticancer effects. Exosomes released by CML cells treated with Curcumin contain a high amount of miR-21 that is shuttled into the endothelial cells in a biologically active form. The treatment of HUVECs with CML Curcu-exosomes reduced RhoB expression and negatively modulated endothelial cells motility. We showed that the addition of CML control exosomes to HUVECs caused an increase in IL8 and VCAM1 levels, but Curcu-exosomes reversed these effects thus attenuating their angiogenic properties. This antiangiogenic effect was confirmed with in vitro and in vivo vascular network formation assays. SWATH analysis of the proteomic profile of Curcu-exosomes revealed that Curcumin treatment deeply changes their molecular properties, in particular, Curcumin induces a release of exosomes depleted in pro-angiogenic proteins and enriched in proteins endowed with anti-angiogenic activity. Among the proteins differential expressed we focused on MARCKS, since it was the most modulated protein and a target of miR-21. Taken together our data indicated that also Curcumin attenuates the exosome's ability to promote the angiogenic phenotype and to modulate the endothelial barrier organization.

2,3,5,4‑tetrahydroxy diphenylethylene‑2‑O‑glucoside inhibits the adhesion and invasion of A549 human lung cancer cells

Lung cancer is considered to be a serious disease that poses a significant threat to human health. 2,3,5,4‑tetrahydroxy diphenylethylene‑2‑O‑glucoside (THSG) is a bioactive compound derived from Polygonum multiflorum Thunb. That has been demonstrated to possess antioxidative, anti‑inflammatory and antitumor activities. However, little is currently known regarding the potential anticancer effects of this compound in lung cancer. Therefore, the present study aimed to investigate the effects of THSG on the adhesion and invasion of A549 human lung cancer cells in vitro, and to identify the putative mechanisms involved. Cell Counting kit‑8 assay was performed to determine A549 cell viability following treatment with various doses (0, 5, 10, 25, 50, 100, 150 and 200 µM) of THSG for 12, 24 and 48 h. In addition, cell adhesion and invasion were determined following treatment of A549 cells with 0, 10, 25 or 50 µM THSG for 1, 2 or 3 h, respectively. Reverse transcription‑quantitative polymerase chain reaction analysis was performed to examine the mRNA expression levels of Snail, E‑cadherin, vimentin, matrix metalloproteinase (MMP) 2 and MMP9 following THSG treatment for 12 h. Western blot analysis was conducted to detect the protein expression levels of Snail, E‑cadherin, vimentin, MMP2 and MMP9 following THSG treatment for 24 h. Treatment with THSG (10, 25 and 50 µM) significantly suppressed the adhesion and invasion of A549 human lung cancer cells in a dose‑dependent manner. In addition, the mRNA and protein expression levels of adhesion and invasion‑associated factors were decreased significantly in A549 cells treated with THSG. In conclusion, THSG effectively suppressed the adhesion and invasion of human lung cancer cells potentially by inhibiting the expression of adhesion and invasion‑related genes.

Up regulation of IL-6 is involved in di (2-ethylhexyl) phthalate (DEHP) induced migration and invasion of non small cell lung cancer (NSCLC) cells

Di (2-ethylhexyl) phthalate (DEHP), which is widely used in polyvinyl chloride materials, can be easily accumulated into human body. Lung cancer cells can be directly exposed to DEHP via inhalation, however, the effects and related mechanisms of DEHP on the progression of non small cell lung cancer (NSCLC) were not illustrated. Our present study revealed that DEHP less than 10^-4M had no significant effect on the proliferation of A549 or H1299 cells, while nanomolar DEHP can trigger the migration and invasion of NSCLC cells. DEHP treatment also increased the expression of interleukin-6 (IL-6) and IL-8. Silencing of IL-6, while not IL-8, can attenuate DEHP induced migration and invasion of NSCLC cells. This was confirmed by result that neutralization antibody of IL-6, while not anti-IL-8, attenuated DEHP induced invasion of A549 cells. The inhibitor of NF-κB, while not ERK1/2 or Akt, abolished DEHP induced up regulation of IL-6 and invasion of NSCLC cells. DEHP treatment can increase the phosphorylation, nuclear localization, and transcriptional activities of p65, one of the major parts of NF-κB complex. Collectively, our study revealed that DEHP can stimulate NSCLC migration and invasion via NF-κB mediated up regulation of IL-6.

Di2-ethylhexyl phthalate disrupts thyroid hormone homeostasis through activating the Ras/Akt/TRHr pathway and inducing hepatic enzymes

Di(2-ethylhexyl) phthalate (DEHP), as a widespread environmental pollutant and an endocrine disruptor, can disturb the homeostasis of thyroid hormones (THs). In order to elucidate roles of the MAPK and PI3K/Akt pathways and hepatic enzymes in thyroid-disrupting effects of DEHP, Sprague-Dawley rats were dosed with DEHP by gavage for 30 consecutive days; Nthy-ori 3-1 cells were treated with DEHP with NAC, k-Ras siRNA or inhibitors (U0126 and wortmannin). Results showed that DEHP led to histopathologic changes in rat thyroid and liver, such as the decrease in thyroid follicular cavity diameter, hepatocyte edema. Triiodothyronine (T3), thyroxine (T4) and thyrotropin releasing hormone (TRH) were reduced. DEHP caused ROS production, oxidative stress and k-Ras upregulation, thereby activating the ERK and Akt pathways in vivo and in vitro. Moreover, TRH receptor (TRHr) level was elevated after the activation of the Akt pathway and was downregulated after the inhibition of the Akt pathway. However, TRHr was not modulated by the ERK pathway. Additionally, hepatic enzymes, including Ugt1a1, CYP2b1, Sult1e1, and Sult2b1, were significantly induced after DEHP exposure. Taken together, DEHP can perturb TH homeostasis and reduce TH levels. The activated Ras/Akt/TRHr pathway and induced hepatic enzymes play vital roles in thyroid-disrupting effects of DEHP.

Conjugation of curcumin-loaded lipid nanoemulsions with cell-penetrating peptides increases their cellular uptake and enhances the anti-inflammatory effects in endothelial cells

OBJECTIVES

To prepare and characterize in vitro and in vivo lipid nanoemulsions (LN) loaded with curcumin (Cm) and functionalized with a cell-penetrating peptide.

METHODS

Curcumin-loaded lipid nanoemulsions (CmLN) functionalized with a nona-arginine peptide (R9-CmLN) have been obtained, characterized and optimized for size, entrapment efficiency and in vitro Cm release. The interaction of R9-CmLN with human endothelial cells (HEC) was investigated using cultured EA.hy926 cells, and in vivo biodistribution studies were performed using C57BL6 mice.

KEY FINDINGS

When used in therapeutically relevant concentration, R9-CmLN have low haemolytic activity, low cytotoxicity on HEC, and show anti-inflammatory effects by reducing the monocytes adhesion to TNF-α activated HEC. Moreover, HEC uptake and internalization of R9-CmLN was significantly higher compared to the non-functionalized CmLN. In vivo biodistribution studies in mice revealed a higher accumulation of R9-CmLN in the liver and the lungs compared to CmLN and the body clearance of the both nanoformulations after 72 h.

CONCLUSIONS

Cell-penetrating peptides-functionalized CmLN have superior characteristics compared to their non-functionalized counterparts: are more efficiently internalized by the cells, produces anti-inflammatory effects in HEC and when administrated intravenously in mice exhibit increased accumulation in the liver and the lungs, suggesting their potential therapeutic applications in different inflammatory pathologies localized in the liver or the lungs.

Plasticizer DBP Activates NLRP3 Inflammasome through the P2X7 Receptor in HepG2 and L02 Cells

Ditubyl phthalate (DBP), one of the most widely used plasticizers, can migrate out to contaminate our bodies and environment. A number of studies have showed that DBP is closely related to liver pathological changes and diseases. Inflammasomes are multiprotein complexes composed of procaspase and pattern recognition receptors such as Nucleotide oligomerization domain (NOD) like receptor family, pyrin domain containing 3 (NLRP3). Activation of NLRP3 inflammasome is implicated in the pathogeneses of liver damage. The aim of this study was to determine the effects of DBP on NLRP3 inflammasome. We found that DBP triggered the activation of NLRP3 inflammasome in hepatocyte cell lines. By using Ca-074-Me, N-acetylcysteine and KN-62, we observed that the P2X7 receptor participated in the DBP-induced activation of NLRP3 inflammasome. DBP could also trigger the ATP release. In conclusion, we demonstrated that DBP is one of the activator of NLRP3 inflammasome and may play an important role in liver damage.

Anti-inflammatory effects of Crataeva nurvala Buch. Ham. are mediated via inactivation of ERK but not NF-κB

ETHNOPHARMACOLOGICAL RELEVANCE

Crataeva nurvala Buch. Ham. is an important medicinal plant in India, and its extracts and components were used to treat various inflammatory diseases, such as urinary tract infection, rheumatoid arthritis, and colitis. However, no systemic studies about anti-inflammatory effects of Crataeva nurvala Buch. Ham. and its underlying mechanisms of action have been reported. This study aimed to explore the anti-inflammatory effects of ethanol extracts of Crataeva nurvala Buch. Ham. (ECN).

MATERIALS AND METHODS

The non-cytotoxic and maximal effective concentration of ECN was determined by measuring the formation of formazan from water-soluble tetrazolium salt in living cells. The inhibitory effect of ECN on nitric oxide (NO) synthesis was measured using Griess reagent, and Enzyme-linked immunosorbent assay (ELISA) was used to measure secreted tumor necrosis factor (TNF)-α and interleukin (IL)-6 protein levels. Furthermore, reverse transcription polymerase chain reaction (RT-PCR) and Western blotting analysis were used to assess the mRNA and protein expression of each inflammatory mediator or relating signaling protein, respectively.

RESULTS

A non-cytotoxic concentration of ECN (≤200 μg/ml) significantly reduced the production of NO and IL-6, but not TNF-α, in lipopolysaccharides (LPS)-stimulated RAW 264.7 macrophages. Decreased production of NO by ECN was correlated with reduced expression of iNOS at the mRNA and protein levels. However, cyclooxygenase (COX)-2 expressions at mRNA and protein level were not regulated by ECN. The mRNA expression of IL-6 and IL-1β, but not TNF-α, was also inhibited by ECN treatment in LPS-stimulated RAW 264.7 macrophages. Reduced production of inflammatory mediators by ECN was followed by decreased activity of mitogen-activated protein kinases (MAPKs), especially extracellular signal-regulated kinase (ERK), but not nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB).

CONCLUSIONS

These results indicate that ECN inhibits LPS-induced inflammatory responses via negative regulation of ERK in murine macrophages, suggesting that ECN is a candidate for alleviating severe inflammation.

Curcumin Suppresses the Production of Pro-inflammatory Cytokine Interleukin-18 in Lipopolysaccharide Stimulated Murine Macrophage-Like Cells

Curcumin is a major bioactive compound of turmeric that exerts its anti-inflammatory effects by suppressing the many pro-inflammatory cytokines and chemokines in a number of cell types and pathologic conditions. Interleukin-18 (IL-18) is a novel pro-inflammatory cytokine which plays an important role not only in generating Th1 responses but also in inducing severe inflammatory reactions. As curcumin induced inhibition of IL-18 production in keratinocytes and mice is well known, effect of curcumin on IL-18 release in macrophages remains unknown. Hence, this present study has been designed to evaluate the effect of curcumin on IL-18 production and necrotic cell death in murine macrophages-like cells treated with or without lipopolysaccharide (LPS). The IL-18 secretion in cell culture supernatants was assayed by enzyme-linked immunosorbent assay and cytotoxicity was determined by lactate dehydrogenase release assay. Our results demonstrate that curcumin significantly inhibited the production of pro-inflammatory cytokine IL-18 in E.coli LPS stimulated murine macrophage-like cells RAW264.7 in a concentration-dependent manner. Interestingly, curcumin had no cytotoxic effect on murine macrophage-like cells. Our findings suggest that curcumin may be used as a potential therapeutic agent for the treatment of inflammatory diseases.

Anti-inflammatory functions of protein C require RAGE and ICAM-1 in a stimulus-dependent manner

By binding β₂-integrins both ICAM-1 and the receptor for advanced glycation end products (RAGE) mediate leukocyte recruitment in a stimulus-dependent manner. Using different inflammatory mouse models we investigated how RAGE and ICAM-1 are involved in anti-inflammatory functions of protein C (PC; Ceprotin, 100 U/kg). We found that, depending on the stimulus, RAGE and ICAM-1 are cooperatively involved in PC-induced inhibition of leukocyte recruitment in cremaster models of inflammation. During short-term proinflammatory stimulation (trauma, fMLP, and CXCL1), ICAM-1 is more important for mediation of anti-inflammatory effects of PC, whereas RAGE plays a major role after longer proinflammatory stimulation (TNFα). In contrast to WT and Icam-1^−/− mice, PC had no effect on bronchoalveolar neutrophil emigration in RAGE^−/− mice during LPS-induced acute lung injury, suggesting that RAGE critically mediates PC effects during acute lung inflammation. In parallel, PC treatment effectively blocked leukocyte recruitment and improved survival of WT mice and Icam-1-deficient mice in LPS-induced endotoxemia, but failed to do so in RAGE-deficient mice. Exploring underlying mechanisms, we found that PC is capable of downregulating intracellular RAGE and extracellular ICAM-1 in endothelial cells. Taken together, our data show that RAGE and ICAM-1 are required for the anti-inflammatory functions of PC.

Curcumin: a novel therapeutic for burn pain and wound healing

INTRODUCTION

Managing burn injury-associated pain and wounds is a major unresolved clinical problem. Opioids, nonsteroidal antiinflammatory drugs (NSAIDs), antidepressants and anticonvulsants remain the most common forms of analgesic therapy to treat burn patients. However, prolonged treatment with these drugs leads to dose escalation and serious side effects. Additionally, severe burn wounds cause scarring and are susceptible to infection. Recent encouraging findings demonstrate that curcumin, a major bioactive component found in turmeric, is a natural pharmacotherapeutic for controlling both severe burn pain and for improved wound healing.

AREAS COVERED

This article covers current pr-clinical and clinical studies on the analgesic and wound healing effects. Particular emphasis has been placed on studies aimed at developing improved curcumin delivery vehicles that increase its bioavailability. Based on the available evidence, a hypothesis is proposed that the dual beneficial effects of curcumin, analgesia and enhanced wound healing are mediated through common anti-inflammatory mechanisms.

EXPERT OPINION

Emerging studies have demonstrated that curcumin is a promising investigational drug to treat both pain and wounds. The adequate control of severe burn pain, particularly over the long courses required for healing, as well improvements in burn wound healing are unmet clinical needs.

Benznidazole prevents endothelial damage in an experimental model of Chagas disease

OBJECTIVES

To evaluate the effect of benznidazole on endothelial activation in a murine model of Chagas disease.

METHODS

A low (30mg/kg/day) and a high (100mg/kg/day) dose of benznidazole were administered to mice infected with Trypanosoma cruzi during the early phases of the infection. The effects of the treatments were assessed at 24 and 90 days postinfection by evaluating the parasitaemia, mortality, histopathological changes and expression of ICAM in the cardiac tissue. The blood levels of thromboxane A2, soluble ICAM and E-selectin were also measured. T. cruzi clearance was assessed by the detection of parasite DNA in the heart tissue of infected mice.

RESULTS

Benznidazole decreased the cardiac damage induced by the parasite, and amastigote nests disappeared at 90 days postinfection. Both doses cleared the parasite from the cardiac tissue at 24 and 90 days postinfection. In addition, benznidazole decreased the thromboxane levels and normalized the plasma sICAM and sE-selectin levels by 90 days postinfection.

CONCLUSIONS

Early administration of benznidazole at a dose as low as 30mg/kg eradicates T. cruzi from cardiac tissue. Additionally, benznidazole prevents cardiac damage and modulates endothelial activation as part of its antichagasic activity.

Protection of vascular endothelium by aspirin in a murine model of chronic Chagas' disease

Chronic Chagas' disease affects 10-30 % of patients infected with Trypanosoma cruzi, and it mainly manifests as cardiomyopathy. Important pathophysiological mechanisms involved in the cardiac lesions include activation of the endothelium and induced microvascular alterations. These processes involve the production of endothelial adhesion molecules and thromboxane A2, which are involved in inflammatory cell recruitment and platelet aggregation, respectively. Cyclooxygenase inhibitors such as aspirin decrease thromboxane production and alter the course of Chagas' disease, both in the acute and chronic phases. We studied the effects of the administration of low and high doses of aspirin during the early phase of T. cruzi infection, following microvascular damage in the context of a chronic murine model of Chagas' disease. The effects of both schedules were assessed at 24 and 90 days postinfection by evaluating parasitemia, mortality, and cardiac histopathological changes as well as the expression of ICAM, VCAM, and E-selectin in cardiac tissue. Thromboxane A2, soluble ICAM, and E-selectin blood levels were also measured. While aspirin did not affect parasitemia or mortality in the infected mice, it decreased both cardiac inflammatory infiltrates and thromboxane levels. Additionally, at 90 days postinfection, aspirin normalized sICAM and sE-selectin levels. Considering the improved endothelial function induced by aspirin, we propose the possibility of including this drug in clinical therapy to treat chronic Chagas' disease.

Sparstolonin B suppresses lipopolysaccharide-induced inflammation in human umbilical vein endothelial cells

Sparstolonin B (SsnB) is an isocoumarin compound isolated from the tubers of both Sparganium stoloniferum and Scirpus yagara. We previously demonstrated that SsnB blocked the Toll-like receptor (TLR) 2- and TLR4-triggered inflammatory signaling in macrophages by inhibiting the recruitment of MyD88 to the TIR domains of TLR2 and TLR4. The present study was designed to examine the effects of SsnB on vascular inflammatory responses in human umbilical vein endothelial cells (HUVECs) challenged by lipopolysaccharide (LPS, a TLR4 ligand). We found that SsnB dose-dependently attenuated the LPS-induced expression of interleukin (IL)-1β and monocyte chemoattractant protein 1 both at the transcription and translation levels in HUVEC. LPS-induced endothelial cell adhesion molecules, intercellular adhesion molecular-1 and vascular cell adhesion molecule-1 expressions were also reduced by treatment with SsnB. In addition, co-incubation with SsnB attenuated THP-1 monocyte adhesion to LPS-activated HUVECs. Furthermore, SsnB efficiently suppressed LPS-induced phosphorylation of extracellular -signal-regulated kinase (Erk1/2) and Akt in HUVECs. These findings show that SsnB can suppress endothelial cell inflammation, suggesting that SsnB might be suitable for development as a therapeutic agent for inflammatory cardiovascular disease.

Apigenin inhibits the expression of IL-6, IL-8, and ICAM-1 in DEHP-stimulated human umbilical vein endothelial cells and in vivo

Di-(2-ethylhexyl) phthalate (DEHP) in house dust is associated with asthma and allergic inflammatory symptoms in children. This study aimed to examine an inhibitory effect of a flavonoid apigenin on DEHP-stimulated inflammatory responses in human umbilical vein endothelial cells (HUVECs). We found that apigenin significantly suppressed DEHP-stimulated expression of intercellular adhesion molecule-1 (ICAM-1) at the mRNA and protein levels and subsequently inhibited the adhesion of THP-1 monocytic cells to HUVECs. Treatment with apigenin also led to a dose-dependent inhibition of mRNA and protein expression of interleukin (IL)-6 and IL-8 in DEHP-stimulated HUVECs. Moreover, pretreatment with apigenin partially inhibited the DEHP-induced activation of c-Jun N-terminal kinase (JNK) but not the degradation of IκBα or the phosphorylation of extracellular-regulated kinase (ERK)1/2, indicating that the inhibitory effect of apigenin on the expression of IL-6, IL-8, and ICAM-1 may be mediated by JNK pathway but not IκBα/nuclear factor-κB or ERK/mitogen-activated protein kinase pathway. Furthermore, apigenin reduced the release of IL-6, IL-8, and ICAM-1 and inhibited compound 48/80-induced systemic anaphylaxis in vivo. These results suggest that apigenin can be used as a therapeutic means for the treatment of DEHP-associated allergic disorders.