The role of aryl hydrocarbon receptor signaling pathway in cardiotoxicity of acute lead intoxication in vivo and in vitro rat model

Heavy Metal Exposure and Cardiovascular Disease

Heavy metals are harmful environmental pollutants that have attracted widespread attention due to their health hazards to human cardiovascular disease. Heavy metals, including lead, cadmium, mercury, arsenic, and chromium, are found in various sources such as air, water, soil, food, and industrial products. Recent research strongly suggests a connection between cardiovascular disease and exposure to toxic heavy metals. Epidemiological, basic, and clinical studies have revealed that heavy metals can promote the production of reactive oxygen species, which can then exacerbate reactive oxygen species generation and induce inflammation, resulting in endothelial dysfunction, lipid metabolism distribution, disruption of ion homeostasis, and epigenetic changes. Over time, heavy metal exposure eventually results in an increased risk of hypertension, arrhythmia, and atherosclerosis. Strengthening public health prevention and the application of chelation or antioxidants, such as vitamins and beta-carotene, along with minerals, such as selenium and zinc, can diminish the burden of cardiovascular disease attributable to metal exposure.

Lead induced genotoxicity and hepatotoxicity in zebrafish (Danio rerio) at environmentally relevant concentration: Nrf2-Keap1 regulated stress response and expression of biomarker genes

Genotoxic and hepatotoxic potentials of Pb at an environmentally relevant concentration (5 ppm) in zebrafish were investigated in the present study. Erythrocytic nuclear abnormality tests revealed the increased frequencies of abnormal erythrocytes after Pb exposure, indicating a strong genotoxic potential of Pb. Multiple stress-related parameters were further evaluated in liver, the major detoxifying organ. Pb caused increased production of ROS, which in turn caused severe oxidative stress. As a result, lipid peroxidation was increased, whereas reduced glutathione level and catalase activity was decreased. Alterations in liver histoarchitecture also served as evidence of Pb-induced hepatotoxicity. Pb-induced ROS stress triggered upregulation of Nrf2, Nqo1, Ho1; downregulation of Keap1, and altered mRNA expressions of Mn-sod, Cu/Zn-sod, gpx1, cyp1a, ucp2 suggesting involvement of Nrf2-Keap1-ARE signaling in cellular defence. Nrf2-keap1 is a sensitive biomarker of Pb-induced ROS stress. Overexpression of Hsp70 and other genes in hepatocytes might help cell survival under oxidative stress generation.

Heavy metals, oxidative stress, and the role of AhR signaling

The Aryl Hydrocarbon Receptor (AhR) is a ligand-activated transcriptional factor pivotal in responding to environmental stress and maintaining cellular homeostasis. Exposure to specific xenobiotics or industrial compounds in the environment activates AhR and its subsequent signaling, inducing oxidative stress and related toxicity. Past research has also identified and characterized several classes of endogenous ligands, particularly some tryptophan (Trp) metabolic/catabolic products, that act as AhR agonists, influencing a variety of physiological and pathological states, including the modulation of immune responses and cell death. Heavy metals, being non-essential elements in the human body, are generally perceived as toxic and hazardous, originating either naturally or from industrial activities. Emerging evidence indicates that heavy metals significantly influence AhR activation and its downstream signaling. This review consolidates current knowledge on the modulation of the AhR signaling pathway by heavy metals, explores the consequences of co-exposure to AhR ligands and heavy metals, and investigates the interplay between oxidative stress and AhR activation, focusing on the regulation of immune responses and ferroptosis.

Pisonia Alba Assisted Synthesis of Nanosilver for Wound Healing Activity

Wound infection is a major clinical challenge, impacting patient morbidity and mortality, with significant economic implications. Our research focused on how Pisonia Alba (PA) leaves, which are used to treat wounds, are used to synthesize silver nanoparticles and study their wound healing property. UV-visible spectroscopy, X-ray diffraction analysis, and s electron microscope (SEM) analysis were employed to evaluate the synthesized silver nanoparticles. Using DLS and Zeta potential analysis, the size and stability of the Pisonia Alba capped silver nanoparticle were investigated. The results showed that Pisonia Alba extract stabilized silver nanoparticles are 63.88 nm in size and have a spherical shape. Antibacterial and antibiofilm potential of synthesized silver nanoparticles against pathogenic organisms Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria were investigated. The in vitro cell scratch wounding assay is used to investigate the wound healing properties of synthesized nanoparticles. Pisonia Alba stabilized silver nanoparticles (PA@AgNPs), in comparison to Pisonia Alba (PA) extract, show effective wound healing characteristics by inducing the formation of collagen and serving as a capable wound healing agent.

Lead Nitrate Induces Inflammation and Apoptosis in Rat Lungs Through the Activation of NF-κB and AhR Signaling Pathways

Lead (Pb) is one of the most frequent hazardous air contaminants, where the lungs are particularly vulnerable to its toxicity. However, the Pb distribution and its impact on lung inflammation/apoptosis and particularly the involvement of nuclear factor kappa B (NF-κB) and aryl hydrocarbon receptor (AhR) signaling pathways in Pb-induced lung toxicity have not yet been fully investigated. Adult male Wistar albino rats were exposed to Pb nitrate 25, 50, and 100 mg/kg b.w. orally for 3 days. The histopathological changes of several rat organs were analyzed using hematoxylin and eosin staining. The concentrations of Pb ion in different organ tissues were quantified using inductive coupled plasma mass spectrometry, while gas chromatography-mass spectrometry was used to identify organic compounds. The changes in the mRNA and protein expression levels of inflammatory and apoptotic genes in response to Pb exposure were quantified by using RT-PCR and Western blot analyses, respectively. Treatment of rats with Pb for three consecutive days significantly increased the accumulation of Pb in lung tissues causing severe interstitial inflammation. Pb treatment also increased the percentage of lung apoptotic cells and modulated apoptotic genes (Bc2, p53, and TGF-α), inflammatory markers (IL-4, IL-10, TNF-α), and oxidative stress biomarkers (iNOS, CYP1A1, EphX) in rat lung tissues. These effects were associated with a significant increase in organic compounds, such as 3-nitrotyrosine and myeloperoxidase, and some inorganic elements, such as selenium. Importantly, the Pb-induced lung inflammation and apoptosis were associated with a proportional increase in the expression of NF-κB and AhR mRNAs and proteins. These findings clearly show that Pb induces severe inflammation and apoptosis in rat lungs and suggest that NF-κB and AhR may play a role in Pb-induced lung toxicity.

Aryl Hydrocarbon Receptors: Evidence of Therapeutic Targets in Chronic Inflammatory Skin Diseases

The aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor, is important for xenobiotic metabolism and binds to various endogenous and exogenous ligands present in the skin. AhR is known to be associated with diseases in various organs; however, its functions in chronic inflammatory skin diseases, such as atopic dermatitis (AD) and psoriasis (PS), have recently been elucidated. Here, we discuss the molecular mechanisms of AhR related to chronic inflammatory skin diseases, such as AD and PS, and the mechanisms of action of AhR on the skin immune system. The importance of AhR molecular biological pathways, clinical features in animal models, and AhR ligands in skin diseases need to be investigated. In conclusion, the therapeutic effects of AhR ligands are demonstrated based on the relationship between AhR and skin diseases. Nevertheless, further studies are required to elucidate the detailed roles of AhR in chronic inflammatory skin diseases.

Developmental toxicant exposures and sex-specific effects on epigenetic programming and cardiovascular health across generations

Despite substantial strides in diagnosis and treatment, cardiovascular diseases (CVDs) continue to represent the leading cause of death in the USA and around the world, resulting in significant morbidity and loss of productive years of life. It is increasingly evident that environmental exposures during early development can influence CVD risk across the life course. CVDs exhibit marked sexual dimorphism, but how sex interacts with environmental exposures to affect cardiovascular health is a critical and understudied area of environmental health. Emerging evidence suggests that developmental exposures may have multi- and transgenerational effects on cardiovascular health, with potential sex differences; however, further research in this important area is urgently needed. Lead (Pb), phthalate plasticizers, and perfluoroalkyl substances (PFAS) are ubiquitous environmental contaminants with numerous adverse human health effects. Notably, recent evidence suggests that developmental exposure to each of these toxicants has sex-specific effects on cardiovascular outcomes, but the underlying mechanisms, and their effects on future generations, require further investigation. This review article will highlight the role for the developmental environment in influencing cardiovascular health across generations, with a particular emphasis on sex differences and epigenetic mechanisms. In particular, we will focus on the current evidence for adverse multi and transgenerational effects of developmental exposures to Pb, phthalates, and PFAS and highlight areas where further research is needed.

Protective effects of bisoprolol against cadmium-induced myocardial toxicity through inhibition of oxidative stress and NF-κΒ signalling in rats

Introduction

The aim of the study was to investigate the mitigative effects of bisoprolol (BIS) in cadmium-induced myocardial toxicity on oxidative stress and its inhibitive effect on nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) signalling in rats.

Material and Methods

Male albino Wistar rats were assigned to control, Cd, BIS 2 (2 mg/kg b.w.) and BIS 8 (8 mg/kg b.w.) groups with nine rats in each. Over four weeks, the control group was administered 1% gum acacia, all other groups received 3mg/kg b.w. CdCl2 dissolved in distilled water, and the BIS groups were additionally given bisoprolol in gum acacia. Blood samples were collected for biochemical estimations. Blood pressure and serum biomarker (lactate dehydrogenase, aspirate transaminase, alanine transferase and creatine kinase-MB, enzyme (superoxide dismutase, lipid hydroxy peroxidase, catalase and malondialdehyde), and tumour necrosis factor alpha (TNF-α) concentrations were measured. Western blot analysis was conducted for NF-κB and glutathione S-transferase (GST). After sacrificing the rats, cardiac tissue samples were examined histopathologically.

Results

Our findings pointed to a significant decrease (P < 0.05) in the studied serum biomarkers and levels of the relevant enzymes in the BIS 8 group compared to the Cd group. A significant decrease (P < 0.05) in NF-kB p65 expression and TNF-α levels was noted in the BIS 8 group relative to the BIS 2 and Cd groups, indicating a reduction at a higher dose. In microscopy, histopathological changes in the cardiac muscles of the BIS 8 group were evident compared to those of the Cd group.

Conclusion

BIS seemed to have protective effects against cardiac injury induced by cadmium and could be considered a novel therapeutic drug and prognostic biomarker in the pathology of the many cardiovascular diseases caused by heavy metal intake.

Bioengineered phytomolecules-capped silver nanoparticles using Carissa carandas leaf extract to embed on to urinary catheter to combat UTI pathogens

Rising incidents of urinary tract infections (UTIs) among catheterized patients is a noteworthy problem in clinic due to their colonization of uropathogens on abiotic surfaces. Herein, we have examined the surface modification of urinary catheter by embedding with eco-friendly synthesized phytomolecules-capped silver nanoparticles (AgNPs) to prevent the invasion and colonization of uropathogens. The preliminary confirmation of AgNPs production in the reaction mixture was witnessed by the colour change and surface resonance plasmon (SRP) band at 410nm by UV–visible spectroscopy. The morphology, size, crystalline nature, and elemental composition of attained AgNPs were further confirmed by the transmission electron microscopy (TEM), selected area electron diffraction (SAED), X-ray diffraction (XRD) technique, Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The functional groups of AgNPs with stabilization/capped phytochemicals were detected by Fourier-transform infrared spectroscopy (FTIR). Further, antibiofilm activity of synthesized AgNPs against biofilm producers such as Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were determined by viability assays and micrographically. AgNPs coated and coating-free catheters performed to treat with bacterial pathogen to analyze the mat formation and disruption of biofilm formation. Synergistic effect of AgNPs with antibiotic reveals that it can enhance the activity of antibiotics, AgNPs coated catheter revealed that, it has potential antimicrobial activity and antibiofilm activity. In summary, C. carandas leaf extract mediated synthesized AgNPs will open a new avenue and a promising template to embed on urinary catheter to control clinical pathogens.

In-situ silver nanoparticles incorporated N, O-carboxymethyl chitosan based adhesive, self-healing, conductive, antibacterial and anti-biofilm hydrogel

Hydrogels are excellent wound healing materials. However, due to the wear and tear at the wound site, hydrogels can lose their structural and functional integrity. To overcome this and to effectively seal the wound and control infection, an in-situ silver nanoparticles (AgNps) incorporated N, O-carboxymethyl chitosan (N, O-CMC) based self-healing hydrogel using ethylenediaminetetraacetic acid-ferric ion (EDTA: Fe³⁺) complex was developed. The prepared N, O-CMC/AgNps hydrogel was characterized using FTIR, SEM, and TEM. The developed N, O-CMC/AgNps hydrogel was found to be adhesive, injectable, conductive, bio-compatible, and showed antibacterial activity against ATCC and clinical strains of E. coli, K. pneumonia, P. aeruginosa, S. aureus and MRSA. N, O-CMC/AgNps hydrogel also showed anti-biofilm activity against S. aureus, E. coli, and P. aeruginosa (ATCC strains). This developed antibacterial and self-healing N, O-CMC/AgNps hydrogel can be used in the treatment of infected wounds.

A toxicity pathway-based approach for modeling the mode of action framework of lead-induced neurotoxicity

BACKGROUND

The underlying mechanisms of lead (Pb) toxicity are not fully understood, which makes challenges to the traditional risk assessment. There is growing use of the mode of action (MOA) for risk assessment by integration of experimental data and system biology. The current study aims to develop a new pathway-based MOA for assessing Pb-induced neurotoxicity.

METHODS

The available Comparative Toxicogenomic Database (CTD) was used to search genes associated with Pb-induced neurotoxicity followed by developing toxicity pathways using Ingenuity Pathway Analysis (IPA). The spatiotemporal sequence of disturbing toxicity pathways and key events (KEs) were identified by upstream regulator analysis. The MOA framework was constructed by KEs in biological and chronological order.

RESULTS

There were a total of 71 references showing the relationship between lead exposure and neurotoxicity, which contained 2331 genes. IPA analysis showed that the neuroinflammation signaling pathway was the core toxicity pathway in the enriched pathways relevant to Pb-induced neurotoxicity. The upstream regulator analysis demonstrated that the aryl hydrocarbon receptor (AHR) signaling pathway was the upstream regulator of the neuroinflammation signaling pathway (11.76% overlap with upstream regulators, |Z-score|=1.451). Therefore, AHR activation was recognized as the first key event (KE1) in the MOA framework. The following downstream molecular and cellular key events were also identified. The pathway-based MOA framework of Pb-induced neurotoxicity was built starting with AHR activation, followed by an inflammatory response and neuron apoptosis.

CONCLUSION

Our toxicity pathway-based approach not only advances the development of risk assessment for Pb-induced neurotoxicity but also brings new insights into constructing MOA frameworks of risk assessment for new chemicals.

Protective Effect of Thymus serrulatus Essential Oil on Cadmium-Induced Nephrotoxicity in Rats, through Suppression of Oxidative Stress and Downregulation of NF-κB, iNOS, and Smad2 mRNA Expression

The purpose of the research was to examine the protective effect of essential oil from Thymus serrulatus Hochst. ex Benth. (TSA oil) against cadmium (Cd)-induced renal toxicity. The experimental protocol was designed using 30 healthy adult Wistar albino rats allocated into five groups containing six animals in each group. Group 1 was treated as normal control and groups 2, 3, 4, and 5 were treated with cadmium chloride (CdCl₂, 3 mg/kg, IP) for 7 days. Group 3 was also treated with silymarin (100 mg/kg, PO) as a standard group, while groups 4 and 5 were administered with TSA oil at doses of 100 and 200 mg/kg PO, respectively. The nephrotoxicity was measured with various parameters such as kidney function markers, oxidative stress markers (glutathione (GSH) and malondialdehyde (MDA)), and messenger ribonucleic acid (mRNA) expression levels of inflammatory factors. The histological studies were also evaluated in the experimental protocol. The CdCl₂-treated groups showed a significant increase in the levels of serum kidney function markers along with MDA levels in kidney homogenate. However, renal GSH level was found to be reduced significantly. It was found that CdCl₂ significantly upregulated the nuclear factor levels of kappaB (NF-κB p65), inducible nitric oxide synthase (iNOS), and small mothers against decapentaplegic (Smad2) as compared to the normal control group. On the other hand, TSA oil significantly improved the increased levels of serum kidney function markers, non-enzymatic antioxidants, and lipid peroxidation. In addition, TSA oil significantly downregulated the increased expression of NF-κB p65, iNOS, and Smad2 in Cd-intoxicated rats. Moreover, the histological changes in the tissue samples of the kidney of Cd-treated groups were significantly ameliorated in the silymarin- and TSA-oil-treated groups. The present study reveals that TSA oil ameliorates Cd-induced renal injury, and it is also proposed that the observed nephroprotective effect could be due to the antioxidant potential of TSA oil and healing due to its anti-inflammatory action.

Ambient particulate matter compositions and increased oxidative stress: Exposure-response analysis among high-level exposed population

BACKGROUND

Oxidative stress has been suggested to be one of the key drivers of health impact of particulate matter (PM). More studies on the oxidative potential of PM alone, but fewer studies have comprehensively evaluated the effects of external and internal exposure to PM compositions on oxidative stress in population.

OBJECTIVE

To comprehensively investigate the exposure-response relationship between PM and its main compositions with oxidative stress indicators.

METHODS

We conducted a cross-sectional study including 768 participants exposed to particulates. Environmental levels of fine particulate matter (PM_2.5), polycyclic aromatic hydrocarbons (PAHs) and metals in PM were measured, and urinary levels of PAHs metabolites and metals were measured as internal dose, respectively. Multivariable linear regression models were used to analyze the correlations of PM exposure and urinary levels of 8-hydroxy-2́'-deoxyguanosine (8-OHdG), and 8-iso-prostaglandin-F2α (8-iso-PGF2α) and malondialdehyde (MDA).

RESULTS

The concentration of both PM_2.5 and total PAHs was significantly correlated with increased urinary 8-OHdG, 8-iso-PGF2α and MDA levels (all p < 0.05). The levels of 4 essential metals all showed significant exposure-response increase in urinary 8-OHdG in both current and non-current smokers (all p < 0.05); ambient selenium, cobalt and zinc were found to be significantly correlated with urinary 8-iso-PGF2α (p = 0.002, 0.003, 0.01, respectively); only selenium and cobalt were significantly correlated with urinary MDA (p < 0.001, 0.01, respectively). Furthermore, we found each one-unit increase in urinary total OH-PAHs generated a 0.32 increase in urinary 8-OHdG, a 0.22 increase in urinary 8-iso-PGF2α and a 0.19 increase in urinary MDA (all p < 0.001). Furthermore, it was found that the level of 12 urinary metals all showed significant and positive correlations with three oxidative stress biomarkers in all subjects (all p < 0.001).

CONCLUSIONS

Our systematic molecular epidemiological study showed that particulate matter components could induce increased oxidative stress on DNA and lipid. It may be more important to monitor and control the harmful compositions in PM rather than overall particulate mass.

Sex-Specific Alterations in Cardiac DNA Methylation in Adult Mice by Perinatal Lead Exposure

Environmental factors play an important role in the etiology of cardiovascular diseases. Cardiovascular diseases exhibit marked sexual dimorphism; however, the sex-specific effects of environmental exposures on cardiac health are incompletely understood. Perinatal and adult exposures to the metal lead (Pb) are linked to several adverse cardiovascular outcomes, but the sex-specific effects of this toxicant on the heart have received little attention. Perinatal environmental exposures can lead to disease through disruption of the normal epigenetic programming that occurs during early development. Using a mouse model of human-relevant perinatal environmental exposure, we investigated the effects of exposure to Pb during gestation and lactation on DNA methylation in the hearts of adult offspring mice (n = 6 per sex). Two weeks prior to mating, dams were assigned to control or Pb acetate (32 ppm) water, and exposure continued until offspring were weaned at three weeks of age. Enhanced reduced-representation bisulfite sequencing was used to measure DNA methylation in the hearts of offspring at five months of age. Although Pb exposure stopped at three weeks of age, we discovered hundreds of differentially methylated cytosines (DMCs) and regions (DMRs) in males and females at five months of age. DMCs/DMRs and their associated genes were sex-specific, with a small, but statistically significant subset overlapping between sexes. Pathway analysis revealed altered methylation of genes important for cardiac and other tissue development in males, and histone demethylation in females. Together, these data demonstrate that perinatal exposure to Pb induces sex-specific changes in cardiac DNA methylation that are present long after cessation of exposure, and highlight the importance of considering sex in environmental epigenetics and mechanistic toxicology studies.

Anti-biofilm and Antibacterial Activities of Silver Nanoparticles Synthesized by the Reducing Activity of Phytoconstituents Present in the Indian Medicinal Plants

Biofilm forming from a variety of microbial pathogens can pose a serious health hazard that is difficult to combat. Nanotechnology, however, represents a new approach to fighting and eradicating biofilm-forming microorganisms. In the present study, the sustainable synthesis and characterization of biocompatible silver nanoparticles (AgNPs) from leaf extracts of Semecarpus anacardium, Glochidion lanceolarium, and Bridelia retusa was explored. Continuous synthesis was observed in a UV–vis spectroscopic analysis and the participating phytoconstituents, flavonoids, phenolic compounds, phytosterols, and glycosides, were characterized by Attenuated total reflectance-Fourier transform infrared spectroscopy. The size and surface charge of the particles were also measured by dynamic light scattering spectroscopy. Scanning electron microscopy study was employed to examine the morphology of the nanoparticles. The spectroscopic and microscopic study confirmed the successful synthesis of AgNPs by plant extracts acting as strong reducing agents. The synthesized AgNPs were screened for antibacterial and anti-biofilm activity against human pathogens Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus. Results of the study demonstrate the potential of phyto-synthesized AgNPs to act as anti-biofilm agents and for other biomedical applications.

The role of NF-κB and AhR transcription factors in lead-induced lung toxicity in human lung cancer A549 cells

Lead (Pb) is recognized as the first heavy metal of the top six toxic air pollutants threatening human health and the second hazardous substance. Pb exposure is associated with lung impairment and high incidences of lung cancer. Nuclear factor kappa B (NF-κB) and aryl hydrocarbon receptor (AhR) signaling pathways are known to be expressed and play an important role in the lung. However, the link between Pb lung toxicity and NF-κB and/or AhR pathways remains unclear. This study was established to explore the role of NF-κB and AhR modulation in Pb-induced lung toxicity in human lung cancer A549 cells. In the current study, treatment of A549 cells with Pb significantly induced cell apoptosis as evidenced by increasing a) the percentage of cells underwent apoptosis determined by flow cytometry and b) p53 mRNA level. Pb treatment induced oxidative stress by a) increasing the formation of reactive oxygen species and b) decreasing GSTA1 mRNA levels. The toxic effects of Pb on the lung was associated with significant increases in NF-κB and AhR levels which was accompanied with increases in downstream targets genes, iNOS and CYP1A1, respectively. Inhibition of NF-κB or AhR either chemically using resveratrol or genetically using small interfering RNA (siRNA) significantly rescued A549 cells from Pb-mediated lung toxicity. The results clearly indicate that Pb-mediated lung toxicities are NF-κB and AhR-dependent mechanism.

The histamine-4 receptor antagonist JNJ7777120 prevents immune abnormalities by inhibiting RORγt/T-bet transcription factor signaling pathways in BTBR T+ Itpr3tf/J mice exposed to gamma rays

Autism is a neurodevelopmental disorder characterized by deficits and qualitative impairments in communication and implicit skill learning. Its prevalence is higher than previous estimates, and treatments have limited efficacy and are costly. Here, we assessed the therapeutic potential of JNJ77777120 (JNJ), a histamine-4 receptor (H4R) antagonist, using BTBR T⁺ Itpr3^tf/J (BTBR) mice, a confirmed model of autism, and C57BL/6J (C57) mice, a commonly chosen reference strain. We first examined the effects of JNJ treatment on BTBR mice exposed to gamma-rays (irradiation-exposed) using a three-chambered apparatus. We further investigated the possible molecular mechanisms through which JNJ administration modulates IL-17A-, RORγT-, IL-22-, T-bet-, STAT3-, ICOS-, and Foxp3-producing CD8⁺ T cells in the spleens of irradiation-exposed BTBR mice. The effects of JNJ administration on the mRNA and protein expression of IL-17A, RORγT, IL-22, T-bet, STAT-3, pSTAT3, IL-10, and Foxp3 in brain tissue were also explored. Results showed that JNJ treatment with irradiation exposure increased social interactions in BTBR mice compared to that in irradiation-exposed BTBR mice. Additionally, JNJ-treated and irradiation-exposed BTBR mice exhibited decreases in IL-17A-, RORγT-, IL-22-, T-bet-, and STAT3-producing CD8⁺ T cells and increases in ICOS- and Foxp3-producing CD8⁺ T cells. Moreover, JNJ treatment and irradiation exposure in BTBR mice regulated the mRNA and protein expression levels of IL-17A, RORγT, IL-22, T-bet, STAT3, pSTAT-3, IL-10, and Foxp3 in the brain tissue. These results suggest that JNJ is useful for the treatment of autism, as this H4R antagonist could block inflammatory cytokine production and transcription factor signaling.

Protective role of Roflumilast against cadmium-induced cardiotoxicity through inhibition of oxidative stress and NF-κB signaling in rats

Cadmium (Cd), a potent cardiotoxic environmental heavy metal, induces oxidative stress and membrane disturbances in cardiac myocytes. Phosphodiesterase (PDEs) retards the positive inotropic effects of β-adrenoceptor activation by decreasing levels of cAMP via degradation. Hence, PDE inhibitors sensitize the heart to catecholamine and are therefore, used as positive inotropic agents. The present study was designed to probe the potential attenuating effects of the selective PDE4 inhibitor (Roflumilast, ROF), on cardiac biomarkers, lipid profile, lipid peroxidation products, antioxidant status and histology of cardiac tissues against Cd-induced cardiotoxicity in rats. Rats were randomly distributed into four different groups: group 1, served as the normal control group. Group 2, served as the toxic control group and were administered Cd (3 mg/kg, i.p.) for next 7 days. Groups 3 and 4, served as treatment groups that received Cd with concomitant oral administration of ROF doses (0.5 and 1.5 mg/kg), respectively for 7 days. Serum samples of toxic control group rats resulted in significant (P < 0.001) increase in lactate dehydrogenase (LDH), creatine phosphokinase (CPK), total cholesterol (TC), triglycerides (TG) and low density lipoproteins (LDL) levels with concomitant decrease in high density lipoproteins (HDL) levels in serum which were found reversed with both of ROF treatment groups. Cd also causes significant increased (P < 0.001) in myocardial malondialdehyde (MDA) contents while cardiac glutathione (GSH) level, superoxide dismutase (SOD) and catalase (CAT) enzyme activities were found decreased whereas both doses of ROF, significantly reversed these oxidative stress markers and antioxidant enzymes. Cardiotoxicity induced by Cd also resulted in enhanced expression of non-phosphorylated and phosphorylated form of NF-κB p65 and decreased expression of glutathione-S-transferase (GST) and NQO1 which were found reversed with ROF treatments, comparable to normal control group. Histopathological changes were also improved by ROF administration as compared to Cd treated rats alone. In conclusion, Roflumilast exhibited attenuating effect against Cd-induced cardiac toxicity.

Roflumilast, a phosphodiesterase 4 inhibitor, attenuates cadmium-induced renal toxicity via modulation of NF-κB activation and induction of NQO1 in rats

Objective:

In the present study, the protective effect of Roflumilast (ROF, a selective phosphodiesterase (PDE-4) inhibitor) was investigated against cadmium (Cd)-induced nephrotoxicity in rats.

Methods:

A total of 24 rats were selected and randomly divided into four groups ( n = 6). Group 1 served as the control; groups 2–4 administered with CdCl2 (3 mg/kg, i.p.) for 7 days; groups 3 and 4 were co-administered with ROF in doses of 0.5 and 1.5 mg/kg, orally for 7 consecutive days. Nephrotoxicity was evaluated by measuring urine volume, urea and creatinine levels in urine and serum. Oxidative stress was confirmed by measuring malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) levels in kidney tissue followed by histopathological studies.

Results:

CdCl2 administration results in a significant ( p < 0.01) decrease in urine volume, urea, and creatinine levels in urine, as well as GSH, SOD, and CAT levels in renal tissue. In addition, Cd also produced significantly increased ( p < 0.01) urea and creatinine levels in serum and TBARS levels in renal tissues. Rats treated with ROF significantly ( p < 0.01) restore the altered levels of kidney injury markers, nonenzymatic antioxidant, as well as depleted enzymes in dose-dependent manner. An increased expression of NF-κB p65 and decreased expression of GST and NQO1 in the Cd only treated group were significantly reversed by high dose of ROF (1.5 mg/kg). Histopathological changes were also ameliorated by ROF administration in Cd-treated groups.

Conclusion:

In conclusion, ROF treatment showed protective effect against renal damage and increased oxidative stress induced by Cd administration.

Dietary grape seed procyanidin extract protects against lead-induced heart injury in rats involving endoplasmic reticulum stress inhibition and AKT activation

To investigate the protective role of grape seed procyanidin extract (GSPE) against lead-induced heart injury and the possible molecular mechanism associated with this event, Wistar rats were orally given GSPE (200 mg/kg) daily with or without lead acetate (PbA) (0.5 g/L) in drinking water for 56 d. GSPE attenuated oxidative stress, heart dysfunction, and lead accumulation in lead-exposed rat hearts. Meanwhile, GSPE inhibited the protein kinase RNA-like endoplasmic reticulum (ER) kinase/eukaryotic initiation factor 2α signaling pathway, and promoted protein kinase B (AKT) and glycogen synthase kinase 3β phosphorylation altered by lead, and regulated lead-activated apoptosis and its related signaling pathway. This study suggests that dietary GSPE ameliorates lead-induced heart injury associated with ER stress inhibition and AKT activation. Dietary GSPE may be a protector against lead-induced heart injury and a novel therapy for lead exposure.

Lead poisoning: acute exposure of the heart to lead ions promotes changes in cardiac function and Cav1.2 ion channels

Lead ions (Pb²⁺) possess characteristics similar to Ca²⁺. Because of this and its redox capabilities, lead causes different toxic effects. The neurotoxic effects have been well documented; however, the toxic effects on cardiac tissues remain allusive. We utilized isolated guinea pig hearts and measured the effects of Pb²⁺ on their contractility and excitability. Acute exposure to extracellular Pb²⁺ had a negative inotropic effect and increased diastolic tension. The speed of contraction and relaxation were affected, though the effects were more dramatic on the speed of contraction. Excitability was also altered. Heart beat frequency increased and later diminished after lead ion exposure. Pro-arrhytmic events, such as early after-depolarization and a reduction of the action potential plateau, were also observed. In isolated cardiomyocytes and tsA 201 cells, extracellular lead blocked currents through Cav1.2 channels, diminished their activation, and enhanced their fast inactivation, negatively affecting their gating currents. Thus, Pb²⁺ was cardiotoxic and reduced cardiac contractility, making the heart prone to arrhythmias. This was due, in part, to Pb²⁺ effects on the Cav1.2 channels; however, other channels, transporters or pathways may also be involved. Acute cardiotoxic effects were observed at Pb²⁺ concentrations achievable during acute lead poisoning. The results suggest how Cav1.2 gating can be affected by divalent cations, such as Pb², and also suggest a more thorough evaluation of heart function in individuals affected by lead poisoning.

Resveratrol mitigates lipopolysaccharide-mediated acute inflammation in rats by inhibiting the TLR4/NF-κBp65/MAPKs signaling cascade

Resveratrol (RSV) is a natural compound exhibiting anti-inflammatory effect, but the anti-inflammatory mechanism has not been fully understood. This study is aimed to evaluate the anti-inflammatory activity and mechanism of RSV in lipopolysaccharides-induced rats’ model. The visceral wet/dry weight ratios and the changes of hematologic and biochemical indices indicated that LPS- stimulation mainly caused damages to liver and lung, while pretreatment with RSV could alleviate the lesions. The cytokine assays showed that RSV could markedly decrease the production of proinflammatory mediators and cytokines (IL-1, IL-1β, IL-6, NO, iNOS and COX-2), and increase the expression of anti-inflammatory mediator (IL-10). RSV could inhibit TLR4 signaling pathway by down-regulating the mRNA levels of MyD88 and TRAF6, and suppressing the TLR4 protein. RSV could inhibit the signaling cascades of NF-κBp65 and MAPKs through down-regulating the mRNA levels of IκBα, p38MAPK, JNK, ERK1, ERK2 and ERK5 in liver and lung, and suppressing the dynamic changes of proteins and phosphorylated proteins including IκBα, NF-κBp65, p38MAPK, JNK, ERK1/2 and ERK5 from tissue’s cytoplasm to nucleus. In conclusion, RSV possessed a therapeutic effect on LPS-induced inflammation in rats and the mechanism mainly attributed to suppressing the signaling cascades of NF-κBp65 and MAPKs by inhibiting the TLR4 signaling pathway.

Ginsenoside Rb1 Inhibits Doxorubicin-Triggered H9C2 Cell Apoptosis via Aryl Hydrocarbon Receptor

Doxorubicin (DOX) is a highly effective chemotherapeutic agent; however, the dose-dependent cardiotoxicity associated with DOX significantly limits its clinical application. In the present study, we investigated whether Rb1 could prevent DOX-induced apoptosis in H9C2 cells via aryl hydrocarbon receptor (AhR). H9C2 cells were treated with various concentrations (− μM) of Rb1. AhR, CYP1A protein and mRNA expression were quantified with Western blot and real-time PCR analyses. We also evaluated the expression levels of caspase-3 to assess the anti-apoptotic effects of Rb1. Our results showed that Rb1 attenuated DOX-induced cardiomyocytes injury and apoptosis and reduced caspase-3 and caspase-8, but not caspase-9 activity in DOX-treated H9C2 cells. Meanwhile, pre-treatment with Rb1 decreased the expression of caspase-3 and PARP in the protein levels, with no effects on cytochrome c, Bax, and Bcl-2 in DOX-stimulated cells. Rb1 markedly decreased the CYP1A1 and CYP1A2 expression induced by DOX. Furthermore, transfection with AhR siRNA or pre-treatment with AhR antagonist CH-223191 significantly inhibited the ability of Rb1 to decrease the induction of CYP1A, as well as caspase-3 protein levels following stimulation with DOX. In conclusion, these findings indicate that AhR plays an important role in the protection of Ginsenoside Rb1 against DOX-triggered apoptosis of H9C2 cells.

Antagonistic effect of selenium on lead-induced inflammatory injury through inhibiting the nuclear factor-κB signaling pathway and stimulating selenoproteins in chicken hearts

In the chicken model of Pb and Se, Se alleviated Pb-induced the changes of inflammatory factors, selenoproteins, and histology. Se alleviated Pb-induced inflammatory injury through inhibiting NF-κB signaling pathway and stimulating selenoproteins in the chicken hearts.

Apremilast reversed carfilzomib-induced cardiotoxicity through inhibition of oxidative stress, NF-κB and MAPK signaling in rats

Carfilzomib (CFZ), is a potent, selective second generation proteasome inhibitor, used for the treatment of multiple myeloma. The aim of the present study was to investigate the possible protective effect of apremilast (AP) on the CFZ -induced cardiotoxicity. Rats were randomly divided into four groups: Group 1, served as the control group, received normal saline. Group 2, served as the toxic group, received CFZ (4 mg/kg, intraperitoneally [i.p.]). Groups 3 and 4, served as treatment groups, and received CFZ with concomitant oral administration of AP in doses of 10 and 20 mg/kg/day, respectively. In the present study, administration of CFZ resulted in a significant increase in serum aspartate transaminase (AST), lactate dehydrogenase (LDH), creatine kinase (CK) and creatine kinase-MB (CK-MB), which were reversed by treatment with AP. CFZ resulted in a significant increase in heart malondialdehyde (MDA) contents and decrease in cardiac glutathione (GSH) level and catalase (CAT) enzyme activity which were significantly reversed by treatment with AP. Induction of cardiotoxicity by CFZ significantly increased caspase-3 enzyme activity which were reversed by treatment with AP. RT-PCR analysis revealed an increased mRNA expression of NF-κB, ERK and JNK which were reversed by treatment with AP in cardiac tissues. Western blot analysis revealed an increased expression of caspase-3 and NF-κB p65 and a decrease expression of inhibitory kappa B-alpha (Iκbα) with CFZ, which were reversed by treatment with AP. In conclusion, apremilast showed protective effect against CFZ-induced cardiotoxicity.

Potent antimicrobial and antibiofilm activities of bacteriogenically synthesized gold–silver nanoparticles against pathogenic bacteria and their physiochemical characterizations

The objective of this study was to develop a bimetallic nanoparticle with enhanced antibacterial activity that would improve the therapeutic efficacy against bacterial biofilms. Bimetallic gold–silver nanoparticles were bacteriogenically synthesized using γ-proteobacterium, Shewanella oneidensis MR-1. The antibacterial activities of gold–silver nanoparticles were assessed on the planktonic and biofilm phases of individual and mixed multi-cultures of pathogenic Gram negative ( Escherichia coli and Pseudomonas aeruginosa) and Gram positive bacteria ( Enterococcus faecalis and Staphylococcus aureus), respectively. The minimum inhibitory concentration of gold–silver nanoparticles was 30–50 µM than that of other nanoparticles (>100 µM) for the tested bacteria. Interestingly, gold–silver nanoparticles were more effective in inhibiting bacterial biofilm formation at 10 µM concentration. Both scanning and transmission electron microscopy results further accounted the impact of gold–silver nanoparticles on biocompatibility and bactericidal effect that the small size and bio-organic materials covering on gold–silver nanoparticles improves the internalization and thus caused bacterial inactivation. Thus, bacteriogenically synthesized gold–silver nanoparticles appear to be a promising nanoantibiotic for overcoming the bacterial resistance in the established bacterial biofilms.

Molecular mechanisms of cardiotoxicity of gefitinib in vivo and in vitro rat cardiomyocyte: Role of apoptosis and oxidative stress

Gefitinib (GEF) is a multi-targeted tyrosine kinase inhibitor with anti-cancer properties, yet few cases of cardiotoxicity has been reported as a significant side effect associated with GEF treatment. The main purpose of this study was to investigate the potential cardiotoxic effect of GEF and the possible mechanisms involved using in vivo and in vitro rat cardiomyocyte model. Treatment of rat cardiomyocyte H9c2 cell line with GEF (0, 1, 5, and 10μM) caused cardiomyocyte death and upregulation of hypertrophic gene markers, such as brain natriuretic peptides (BNP) and Beta-myosin heavy chain (β-MHC) in a concentration-dependent manner at the mRNA and protein levels associated with an increase in the percentage of hypertrophied cardiac cells. Mechanistically, GEF treatment caused proportional and concentration-dependent increases in the mRNA and protein expression levels of apoptotic markers caspase-3 and p53 which was accompanied with marked increases in the percentage of H9c2 cells underwent apoptosis/necrosis as compared to control. In addition, oxidative stress marker (heme oxygenase-1, HO-1) and the formation of reactive oxygen species were increased in response to GEF treatment. At the in vivo level, treatment of Wistar albino rats for 21days with GEF (20 and 30mg/kg) significantly increased the cardiac enzymes (CK, CKmb, and LDH) levels associated with histopathological changes indicative of cardiotoxicity. Similarly, in vivo GEF treatment increased the mRNA and protein levels of BNP and β-MHC whereas inhibited the antihypertrophoic gene (α-MHC) associated with increased the percentage of hypertrophied cells. Furthermore, the mRNA and protein expression levels of caspase-3, p53, and HO-1 genes and the percentage of apoptotic cells were significantly increased by GEF treatment, which was more pronounced at the 30mg/kg dose. In conclusion, GEF induces cardiotoxicity and cardiac hypertrophy in vivo and in vitro rat model through cardiac apoptotic cell death and oxidative stress pathways.

Design and Synthesis of N-Arylphthalimides as Inhibitors of Glucocorticoid-Induced TNF Receptor-Related Protein, Proinflammatory Mediators, and Cytokines in Carrageenan-Induced Lung Inflammation

N-Arylphthalimides (1-10P) derived from thalidomide by insertion of hydrophobic groups were evaluated for anti-inflammatory activity, and (4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-N'-[(4-ethoxyphenyl)methylidene]benzohydrazide 6P was identified as a promising anti-inflammatory agent. Further testing confirmed that compared with the control, 6P treatment resulted in a considerable decrease in CD4(+), NF-κB p65(+), TNF-α(+), IL-6(+), GITR(+), and IL-17(+) cell populations and an increase in the Foxp3(+), CD4(+)Foxp3(+), and IκBα(+) populations in whole blood and pleural fluid of a mouse model of lung inflammation. Moreover, treatment with compound 6P decreased the proteins associated with inflammation including TNF-α, IL-6, IL-17, GITR, NF-κB, COX-2, STAT-3, and iNOS and increased the anti-inflammatory mediators such as IL-10 and IL-4. Further, histopathological examination confirmed the potent anti-inflammatory effects of compound 6P. Thus, the N-arylphthalimide derivative 6P acts as a potent anti-inflammatory agent in the carrageenan-induced lung inflammation model, suggesting that this compound may be useful for the treatment of inflammation in a clinical setting.

Histamine 4 receptor promotes expression of costimulatory B7.1/B7.2 molecules, CD28 signaling and cytokine production in stress-induced immune responses

Recently, the expression of histamine 4 receptor (H4R) on neurons was reported, however its function in cells within the central nervous system (CNS) remains poorly understood. To this end, we used the H4R agonist, 4-methylhistamine (4-MeH), and the H4R antagonist, JNJ77777120 (JNJ), to investigate the function of H4R signaling in immune cells in a murine model of chronic stress. Treatment of stressed mice with 4-MeH resulted in an increase in the proportion of lymphocyte subsets (CD3(+), CD8(+), CD28(+), and CD4(+)CD28(+)) and cells expressing the co-stimulatory molecules CD80(+) (B7.1) and CD86(+) (B7.2) in heparinized blood as compared to normal control (NC) and stressed control (SC) groups. We also observed that as compared to NC and SC mice, 4-MeH-treated mice showed greater production of IL-2(+), IL-6(+), IL-9(+), IL-21(+), and IL-27(+) cytokines in the spleen and by splenic CD4(+) T cells. Furthermore, 4-MeH treatment of stressed mice led to an increase in the levels of serum Th1/Th17 cytokines and corticosterone, and a decrease in Th2 cytokines. Treatment of chronically-stressed mice with 4-MeH also augmented expression of IL-6, IL-21, NF-κB p65, and STAT3 mRNA. Moreover, Western blot analyses confirmed increased protein expression of NF-κB, iNOS, and STAT3 expression following 4-MeH treatment of chronically-stressed mice as compared to controls. These proteins provide a novel relevant targets for the manipulation of chronic stress induced immune regulation. In striking contrast, treatment of stressed mice with the H4R antagonist, JNJ, resulted in a substantial reduction in all of the aforementioned effects upon immune cell percentages and cytokine production.

The role of Nrf2 in protection against Pb-induced oxidative stress and apoptosis in SH-SY5Y cells

Lead exerts severe adverse effects on the nervous system in which oxidative stress might mediate impairments. In this study, we focused on Nrf2, which has been identified to significantly influence the protection of a cellular system against many xenobiotic compounds. We found that PbAc exhibited neurotoxicity mainly through oxidant-based processes and could be inhibited by NAC and DPI in SH-SY5Y cells. As a defense response, Nrf2 was activated when exposed to PbAc, thereby inducing a rapid increase in Nrf2 nuclear accumulation, as well as Nrf2-ARE binding activities in a ROS-dependent manner. Analysis of Nrf2-regulated gene expression and protein showed that PbAc could induce the mRNA transcription of HO-1, GSTα1, GCLM, GCLC, and NQO1, as well as the protein expression of HO-1 and γ-GCS. The responses of these genes to PbAc were regulated by Nrf2. Silencing Nrf2 expression in SH-SY5Y cells inhibited PbAc-induced gene transcription and protein expression. Overexpression of Nrf2 led to decreased ROS production and cell apoptosis, as well as increased cell viability under PbAc exposure. These results indicated that the Nrf2-ARE system exhibited a protective role in Pb-induced neurotoxicity, providing potential therapeutic strategies for the prevention and treatment of Pb-related diseases.

Effects of sexually dimorphic growth hormone secretory patterns on arachidonic acid metabolizing enzymes in rodent heart

The arachidonic acid (AA) metabolizing enzymes are the potential therapeutic targets of cardiovascular diseases (CVDs). As sex differences have been shown in the risk and outcome of CVDs, we investigated the regulation of heart AA metabolizing enzymes (COXs, LOXs, and CYPs) by sex-dependent growth hormone (GH) secretory patterns. The pulsatile (masculine) GH secretion at a physiological concentration decreased CYP1A1 and CYP2J3 mRNA levels more efficiently in the H9c2 cells compared with the constant (feminine) GH secretion; however, CYP1B1 mRNA levels were higher following the pulsatile GH secretion. Sex differences in CYP1A1, CYP1B1, and CYP2J11 mRNA levels were observed in both the wild-type and GHR deficient mice. No sex differences in the mRNA levels of COXs, LOXs, or CYP2E1 were observed in the wild-type mice. The constant GH infusion induced heart CYP1A1 and CYP2J11, and decreased CYP1B1 in the male C57/B6 mice constantly infused with GH (0.4 μg/h, 7 days). The activity of rat Cyp2j3 promoter was inhibited by the STAT5B protein, but was activated by C/EBPα (CEBPA). Compared with the constant GH administration, the levels of the nuclear phosphorylated STAT5B protein and its binding to the rat Cyp2j3 promoter were higher following the pulsatile GH administration. The constant GH infusion decreased the binding of the nuclear phosphorylated STAT5B protein to the mouse Cyp2j11 promoter. The data suggest the sexually dimorphic transcription of heart AA metabolizing enzymes, which might alter the risk and outcome of CVDs. GHR-STAT5B signal transduction pathway may be involved in the sex difference in heart CYP2J levels.

Molecular and Histopathological Study on the Ameliorative Effects of Curcumin Against Lead Acetate-Induced Hepatotoxicity and Nephrototoxicity in Wistar Rats

Lead (Pb(2+)) toxicity is the most common form of heavy metal intoxication in humans and animals. Therefore, the current study was conducted to evaluate the potential ameliorative effects of curcumin on lead acetate (LA)-induced deleterious effects in the liver and kidney. Forty male Wistar rats were divided into four equal groups; first group was used as a control and given both corn oil orally and vehicle of lead acetate intraperitoneally (i.p). Groups from 2-4 were treated with lead acetate (LA; 50 mg/kg BW i.p), curcumin (200 mg/kg BW orally), and curcumin plus lead acetate, respectively. Curcumin was administered 3 weeks before LA injection for 7 days. Pb(2+)-intoxicated rats have higher Pb(2+) levels compared to other treated groups. Results revealed that lead acetate significantly increased the serum levels of hepatic transaminases (GPT and GOT), urea and creatinine, while albumin was significantly decreased. In parallel, serum IgG, IgM, and IgA were significantly decreased in LA-injected rats. LA groups showed decrease in messenger RNA (mRNA) expression of catalase, SOD, GST, GPx, and alpha-1 acid glycoprotein (AGP), while the gene expression of desmin, vimentin, transforming growth factor-β1 (TGF-β1), monocyte chemoattractant protein-1 (MCP-1), and alpha-2 macroglobulin (α-2M) was increased. Prior and coadministration of curcumin with LA for 7 days significantly improved the ameliorated changes in liver and kidney, immunoglobulins, and mRNA expression. Moreover, curcumin ameliorated LA-induced congestion of hepatic and renal blood vessels and decreased fibrous tissue proliferation and necrosis of hepatocytes. In the kidney, LA-induced degeneration in tubular epithelium and intraluminal hyaline casts and prior curcumin administration restored normal renal structure with mild congestion of renal blood vessels. The results clarify the potential of curcumin to counteract the immunosuppressive alteration in gene expression as well as hepatic and renal damage occurred after Pb(2+) intoxication.

Stimulation of the histamine 4 receptor with 4-methylhistamine modulates the effects of chronic stress on the Th1/Th2 cytokine balance

Alterations to the immune system caused by stress have been considered to markedly increase the risk for immune-related diseases such as cancer and autoimmune disorders. We investigated the potential anti-stress effects of the histamine 4 receptor (H4R) agonist, 4-methylhistamine (4-MeH), in a murine stress model. Mice were placed in 50ml conical centrifuge tubes for 12h followed by a 12h rest. The effects of treatment with 4-MeH (30mg/kg, i.p., twice daily) for 2 days were assessed. At 2 days after physical restraint, mice were sacrificed and tissues harvested. We evaluated the effects of 4-MeH treatment on CD4(+) T cell production, and intracellular IFN-γ and IL-4 expression in these cells. We also assessed IL-1β, IFN-γ, TNF-α, and IL-4 mRNA expression as well as IFN-γ, TNF-α, GITR, Ox40 and IL-4 protein expression in the spleen. The results showed that 4-MeH treatment of stressed mice results in a substantial increase in the CD4(+) T cells as well as in IFN-γ production by these cells. Compared to both untreated and stressed controls. In contrast, IL-4 expression decreased significantly following 4-MeH treatment of mice. Moreover, stimulation of the H4R resulted in up-regulated expression of IL-1β, IFN-γ and TNF-α mRNAs and decreased the expression of IL-4. Western blot analysis confirmed decreased protein expression of IFN-γ, TNF-α, GITR, Ox40 and increased IL-4 in the SC group and treatment of mice with 4-MeH reversed these effects. Our results confirm the significant impact of chronic stress on T cell function and production of Th1/Th2 mediators H4R.

The role of poly(ADP-ribose) polymerase-1 inhibitor in carrageenan-induced lung inflammation in mice

Increasing indication is unveiling a role for poly(ADP-ribose) polymerase (PARP)-1 in the regulation of inflammatory/immune responses. The aim of the present study was to determine the potential anti-inflammatory effects of PARP-1 inhibitor 5-aminoisoquinolinone (5-AIQ) to explore the role of PARP-1 inhibitor in a mouse model of carrageenan-induced lung inflammation. A single dose of 5-AIQ (1.5mg/kg) was administered intraperitoneally (i.p.) 1h before λ-carrageenan (Cg) administration. We assessed the effects of 5-AIQ treatment on CD25(+), GITR(+), CD25(+)GITR(+), IL-17(+) and Foxp3(+) cells which were investigated using flowcytometry in pleural exudates and heparinized blood. We also evaluated mRNA expressions of IL-6, TNF-α, IL-1β, IL-10, CD11a, l-selectin (CD62L), ICAM-1, MCP-1, iNOS and COX-2 in the lung tissue. We further examined the effects of 5-AIQ on the key mediators of inflammation, namely COX-2, STAT-3, NF-kB p65, PARP-1, IkB-α and IL-4 protein expression in the lung tissue using western blotting. The results illustrated that the numbers of T cell subsets, IL-17(+) cytokine levels were markedly increased and Foxp3(+) production decreased in the Cg group. Furthermore, Cg-induced up-regulation of adhesion molecules, pro-inflammatory mediators and chemokine expressions. Western blot analysis revealed an increased protein expressions of COX-2, STAT-3 NF-kB p65 and PARP-1 and decreased IkB-α and IL-4 in the Cg group. PARP-1 inhibitor via 5-AIQ treatment reverses the action significantly of all the previously mentioned effects. Moreover, histological examinations revealed anti-inflammatory effects of 5-AIQ, whereas Cg-group aggravated Cg-induced inflammation. Present findings demonstrate the potent anti-inflammatory action of the PARP-1 inhibitor in acute lung injury induced by carrageenan.

Enhanced antibacterial and anti-biofilm activities of silver nanoparticles against Gram-negative and Gram-positive bacteria

Silver nanoparticles (AgNPs) have been used as antibacterial, antifungal, antiviral, anti-inflammtory, and antiangiogenic due to its unique properties such as physical, chemical, and biological properties. The present study was aimed to investigate antibacterial and anti-biofilm activities of silver nanoparticles alone and in combination with conventional antibiotics against various human pathogenic bacteria. Here, we show that a simple, reliable, cost effective and green method for the synthesis of AgNPs by treating silver ions with leaf extract of Allophylus cobbe. The A. cobbe-mediated synthesis of AgNPs (AgNPs) was characterized by ultraviolet-visible absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS), and transmission electron microscopy (TEM). Furthermore, the antibacterial and anti-biofilm activity of antibiotics or AgNPs, or combinations of AgNPs with an antibiotic was evaluated using a series of assays: such as in vitro killing assay, disc diffusion assay, biofilm inhibition, and reactive oxygen species generation in Pseudomonas aeruginosa, Shigella flexneri, Staphylococcus aureus, and Streptococcus pneumonia. The results suggest that, in combination with antibiotics, there were significant antimicrobial and anti-biofilm effects at lowest concentration of AgNPs using a novel plant extract of A. cobbe, otherwise sublethal concentrations of the antibiotics. The significant enhancing effects were observed for ampicillin and vancomycin against Gram-negative and Gram-positive bacteria, respectively. These data suggest that combining antibiotics and biogenic AgNPs can be used therapeutically for the treatment of infectious diseases caused by bacteria. This study presented evidence of antibacterial and anti-biofilm effects of A. cobbe-mediated synthesis of AgNPs and their enhanced capacity against various human pathogenic bacteria. These results suggest that AgNPs could be used as an adjuvant for the treatment of infectious diseases.