A CCL chemokine-derived peptide (CDIP-2) exerts anti-inflammatory activity via CCR1, CCR2 and CCR3 chemokine receptors: Implications as a potential therapeutic treatment of asthma.

Allergic asthma is a chronic inflammatory disease characterized by the accumulation of eosinophils, Th2 cells and mononuclear cells in the airways, leading to changes in lung architecture and subsequently reduced respiratory function. We have previously demonstrated that CDIP-2, a chemokine derived peptide, reduced in vitro chemotaxis and decreased cellular infiltration in a murine model of allergic airway inflammation. However, the mechanisms involved in this process have not been identified yet. Now, we found that CDIP-2 reduces chemokine-mediated functions via interactions with CCR1, CCR2 and CCR3. Moreover, using bone marrow-derived eosinophils, we demonstrated that CDIP-2 modifies the calcium fluxes induced by CCL11 and down-modulated CCR3 expression. Finally, CDIP-2 treatment in a murine model of OVA-induced allergic airway inflammation reduced leukocyte recruitment and decreases production of cytokines. These data suggest that chemokine-derived peptides represent new therapeutic tools to generate more effective antiinflammatory drugs.

CD11c decrease in mouse thymic dendritic cells after vanadium inhalation.

Vanadium (V) is a transition metal found in air adsorbed onto suspended particles. As a result, urban populations are often exposed to this element as a constituent of particulate matter (PM). One aspect of the myriad toxicities that might arise from these exposures is altered immune responses. Previous reports from the laboratory reported modifications in splenic architecture - with germinal center hyperplasia and a suppressed humoral immune response - in mice that had been exposed to vanadium agents via inhalation. This paper reports a decrease in the presence of the CD11c surface marker on mouse thymic dendritic cells (DC) as a result of host exposure to vanadium (here, in the form of vanadium pentoxide; V(2)O(5)) over a period of 4 weeks. All results were obtained using immunohistochemistry and flow cytometry. It is surmised that this decrease might induce a dysfunction, including possible negative selection of T-cells, which could increase the presence of autoreactive clones in the exposed host. Such an outcome could, in turn, increase the risk for development of autoimmune reactions in different organs specifically, and of autoimmune diseases in general in these V-exposed hosts.

Vanadium inhalation in a mouse model for the understanding of air-suspended particle systemic repercussion.

There is an increased concern about the health effects that air-suspended particles have on human health which have been dissected in animal models. Using CD-1 mouse, we explore the effects that vanadium inhalation produce in different tissues and organs. Our findings support the systemic effects of air pollution. In this paper, we describe our findings in different organs in our conditions and contrast our results with the literature.

Toxic effects of inhaled manganese on the olfactory bulb: an ultrastructural approach in mice.

Olfactory dysfunction is a common symptom reported by patients with neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. Despite the knowledge gathered about the pathology of these diseases, little information has been generated regarding the ultrastructure modifications of the granule cells that regulate the information for odor identification. Swollen organelles and nuclear invaginations identified the exposed mice. Necrosis was evidenced at 4th week of exposure, whereas apoptosis arose at 8th week of exposure. A ruffled electron-dense membrane changes were also found. The changes observed could be explained by the reactive oxygen species generated by manganese and its effects on the membrane's structure and on the cytoskeleton's function. This study contributes to correlate metal air pollution and neurodegenerative changes with olfactory affection.

Endogenous antioxidants and nasal human epithelium response to air pollutants: genotoxic and inmmuno-cytochemical evaluation.

Nasal epithelium is a source for identifying atmospheric pollution impact. Antioxidants play a relevant role in the protection of the cells from environmental injury, but scarce information is available about the interaction of endogenous antioxidants and genotoxic damage in nasal epithelium from urban populations highly exposed to traffic-generated air pollutants. An immunocytochemical and genotoxic evaluation was implemented in nasal cell epithelium in a population chronically exposed to atmospheric pollution from autumn 2004 to autumn 2005. Superoxide dismutase (SOD) and Catalase (CAT) were evaluated in nasal scrapings by morphometry and genotoxicity by comet assay. An increase in DNA damage correlates with a decrease in SOD and CAT in nasal cells during autumn and the inverse result was observed during summer (R = 0.88). Not only should exogenous antioxidant supplements be encouraged, but also a healthy diet to strengthen intracellular defenses against oxidative stress induced by exposure to air pollutants.

The altered expression of inflammation-related molecules and secretion of IL-6 and IL-8 by HUVEC from newborns with maternal inactive systemic lupus erythematosus is modified by estrogens.

Systemic lupus erythematosus (SLE) predominantly affects women, especially those in reproductive age. Genetic contributions to disease susceptibility as well as immune dysregulation, particularly persistent inflammatory responses, are considered essential features. Our aim was to determine whether human umbilical vein endothelial cells (HUVEC) isolated from healthy newborns to women with inactive SLE show inflammation-related abnormalities that might lead to an early development of SLE in the offsprings. HUVEC isolated from six women with inactive SLE were stimulated with 2.5 ng/mL of TNF-alpha and/or physiological and pharmacological doses of 17-I(2) estradiol (E2). Then the expression of VCAM-1, ICAM-1, E-selectin, toll-like receptor-9 (TLR-9), heat shock protein 70 (HSP70) and HSP90 were measured. The concentrations of IL-6, IL-8, and IL-10 were also determined in maternal serum and in TNF-alpha stimulated and non-stimulated HUVEC culture supernatant. HUVEC from children with no family history of autoimmune disease served as controls. Our results showed that in HUVEC from SLE+ mothers, a constitutively low expression of adhesion molecules was enhanced by TNF-alpha treatment. The E2 (1 ng/mL) increased the expression of adhesion molecules but had no effect upon TNF-alpha-treated cells. IL-6 was constitutively higher in SLE+ HUVEC, whereas IL-8 was lower; E2 treatment diminished the latter. The E2 had no effect upon IL-6 and IL-8 secretions in TNF-alpha-treated cells. SLE+ HUVEC showed a disordered cytoskeleton and overexpressed HSP70, HSP90, and TLR-9. Our results indicate that endothelial cells of newborns to SLE+ mothers are in a proinflammatory condition which can be upregulated by estrogens.

Vanadium pentoxide inhalation provokes germinal center hyperplasia and suppressed humoral immune responses.

Vanadium, an important air pollutant derived from fuel product combustion, aggravates respiratory diseases and impairs cardiovascular function. In contrast, its effects on immune response are conflicting. The aim of our work was to determine if spleens of vanadium-exposed CD1 mice showed histological lesions that might result in immune response malfunction. One hundred and twelve CD-1 male mice were placed in an acrylic box and inhaled 0.02 M vanadium pentoxide (V2O5); actual concentration in chamber approximately 1.4 mg V2O5/m(3)) for 1 hr/d, twice a week, for 12 wk. Control mice inhaled only vehicle. Eight mice were sacrificed prior to the exposures. Eight control and eight V2O5-exposed mice were sacrificed 24 hr after the second exposure of each week until the 12-wk study was over. Another 8 mice that completed the 12-wk regimen were immunized with recombinant Hepatitis B surface antigen (HBsAg; three times over an 8-wk period) before sacrifice and analyses of their levels of anti-HBsAg antibody (HBSAb) using ELISA. In all studies, at sacrifice, blood samples were obtained by direct heart puncture and the spleen was removed, weighed and processed for H-E staining and quantitation of CD19 cells. The results indicated that the spleen weight of V2O5-exposed animals peaked at 9 wk (546 +/- 45 vs. 274 +/- 27 mg, p < 0.0001) and thereafter progressively decreased (321 +/- 39 mg at 12 wk, p < 0.001; control spleen = 298 +/- 35 mg). Spleens of V2O5-exposed animals showed an increased number of very large and non-clearly delimited germinal centers (that contained more lymphocytes and megakaryocytes) compared to those of control mice. In addition, their red pulp was poorly delimited and had an increase in CD19+ cells within hyperplasic germinal nodes. The mean HBsAb levels in immunized control mice were greater than that in the exposed hosts (i.e., OD = 0.39 +/- 0.03 vs. 0.11 +/- 0.05, p < 0.01). HBsAb avidity dropped to a value of 40 in V2O5-exposed animals vs. 86 in controls (p < 0.0001). We conclude that the chronic inhalation of V2O5, a frequent particle (PM(2.5)) component, induces histological changes and functional damage to the spleen, each of which appear to result in severe effects on the humoral immune response.

Matrix metalloproteinases 2 and 9 in central nervous system and their modification after vanadium inhalation.

Vanadium (V) derivatives are well-known environmental pollutants and its toxicity has been related with oxidative stress. Toxicity after vanadium inhalation on the substantia nigra, corpus striatum, hippocampus and ependymal epithelium was reported previously. The purpose of this study was to analyse the role of matrix metalloproteinases 2 (MMP-2) and 9 (MMP-9) in the changes observed in brain tissue after chronic V inhalation. Mice were exposed to vaporized, vanadium pentoxide 0.02 m in deionized water for 1 h twice a week, and killed at 1 h, 1, 2 and 4 weeks after exposure. The brain was removed and the olfactory bulb, prefrontal cortex, striatum and hippocampus were dissected and the MMP content was obtained by zymography. The results showed that MMP-9 increased in all the structures at the end of the exposure, although in the hippocampus this increment was evident after 1 week of exposure. When MMP-2 was analysed in the olfactory bulb and prefrontal cortex it remained unchanged throughout the whole exposure, while in the hippocampus it increased at week 4, while in the striatum MMP-2 increased from the second week only, through the whole experiment. These results demonstrate that V increased MMPs in different structures of the CNS and this change might be associated with the previously reported modifications, such as dendritic spine loss and neuronal cell death. The modifications in MMPs could be related with blood-brain barrier (BBB) disruption which was reported previously. Oxidative stress might also be involved in the activation of these gelatinases as part of the different mechanisms which take place in V toxicity in the CNS.

Genotoxic differences by sex in nasal epithelium and blood leukocytes in subjects residing in a highly polluted area.

We describe differences by sex in genotoxic damage found in a population of medical students exposed to a highly oxidative atmosphere, compared with a control group, measured by the single-cell gel electrophoresis assay and histological changes in nasal epithelium smears. Cells were obtained from the nasal epithelium and blood leukocytes. Higher DNA damage in nasal cells and leukocytes was found in males compared to females and control subjects. The percentage of squamous metaplastic changes in the nasal epithelium was also higher in males compared with females and controls. The co-mutation of normal nasal epithelium by squamous cells might modify its protective function in the nose, increasing the risk of damage to the lower respiratory tract. Although, as medical students, males and females were exposed to the same environment and activity patterns, male genotoxicity damage was higher in control and exposed subjects. More research should be done in order to identify direct or indirect sexual hormone intervention.

Gastric gross and microscopic lesions caused by the UNAM-97 variant strain of infectious bronchitis virus after the eighth passage in specific pathogen-free chicken embryos.

Herein we report a description of gross and microscopic lesions found in specific pathogen-free chicken embryos caused by UNAM-97 infectious bronchitis virus (IBV) variant strain after the eighth passage. Embryos were divided into three groups and were inoculated in the chorioallantoic sac with 0.2 mL of UNAM-97, Mass 41 IBV (positive control), or sterile PBS (negative control). Forty-eight hours later the allatoic fluid was taken and used to start a cycle of eight passages through 9-d-old embryos. Seven days after the last passage, embryos were harvested and macroscopic lesions in all organs were recorded. Proventriculus and gizzard samples were obtained from all embryos and routinely processed for microscopic and ultrastructural examinations. The UNAM-97 IBV variant strain caused two macroscopic lesions uncommon for Mexican strains: thin-walled proventriculus and gizzard, as well as urate accumulation within an extra-embryonic peritoneal sac, leaving the body through the umbilical duct and accompanied by the yolk sac. At microscopic level, two relevant findings were observed to be produced by this variant. In the proventriculus, there was a decrease in the gland papillary branching, while the gizzard showed a significant reduction in mucosa thickness and tubular-to-proliferative-cell ratio, as well as an absence of hyaline secretion in the lumen. Electrodense material scattered in proventricular and gizzard cells was observed, with a structure consistent with that of coronaviruses. These pathological chicken embryo findings have not been reported as being caused by other IBV strains in Mexico.

Manganese in lung tissue: study of Mexico City residents' autopsy records from the 1960s and 1990s.

During the conduct of autopsies performed on residents of Mexico City during the 1960s (20 males, 19 females) and 1990s (30 males and 18 females), concentrations of manganese in lung were studied with atomic absorption spectrometry. Concentrations of manganese were not significantly greater in the samples obtained in the 1990s (1.87+/-0.8 microg/gm [mean +/- standard deviation]) than in samples from the 1960s (1.72+/-1.2 microg/gm). Concentrations were not correlated with gender, smoking habit, age, or cause of death; however, there was a correlation with occupation. The findings suggest that manganese exposure via air does not represent a health hazard to residents of Mexico City, given that lung concentrations of manganese remained stable during the 30-y period studied. Investigators should monitor concentrations of manganese in suspended particles to follow-up on these findings.

Evaluation of DNA damage in exfoliated tear duct epithelial cells from individuals exposed to air pollution assessed by single cell gel electrophoresis assay.

The search for relevant target cells for human monitoring purposes has increased during the last few years. Cells such as sperm, buccal or nasal and gastric epithelium are being used. In this study, we report the use of exfoliated tear duct epithelial cells as a potential material for human biomonitoring studies, since these cells are a target for environmental pollutants. We employed the alkaline single cell gel electrophoresis (SCGE) assay to evaluate for differences in the basal level of DNA damage between young adults from the south (exposed mainly to high levels of ozone) and from the north (exposed principally to hydrocarbons) regions of Mexico City. We found an increase in DNA migration in tear duct epithelial cells from individuals who live in the southern part of the city compared to those living in the northern part. Moreover, young people who live in the southwest part of the city with the highest values of ozone presented the highest values of DNA damage. These results show the feasibility of using exfoliated tear duct epithelial cells in human biomonitoring studies.

Morphologic alteration of the olfactory bulb after acute ozone exposure in rats.

The interaction of ozone with some molecules results in an increased production of free radicals. The objective of this study was to identify whether acute ozone exposure to 1-1.5 ppm for 4 h, produced cytological and ultrastructural modifications in the olfactory bulb cells. The results showed that in rats exposed to ozone there was a significant loss of dendritic spines on primary and secondary dendrites of granule cells, whereas the control rats did not present such changes. Besides these exposed cells showed vacuolation of neuronal cytoplasm, swelling of Golgi apparatus and mitochondrion, dilation cisterns of the rough endoplasmic reticulum. These findings suggest that oxidative stress produced by ozone induces alterations in the granule layer of the olfactory bulb, which may be related to functional modifications.

Memory deterioration in an oxidative stress model and its correlation with cytological changes on rat hippocampus CA1.

Exposure to ozone results in an increased production of free radicals which causes oxidative stress. The purpose of this study was to determine the effects of ozone exposure on memory and its correlation with the cytology of the hippocampus. Twenty-four male Wistar rats were exposed to 1 ppm (parts per million) ozone for 4 h in a closed chamber. Control group was exposed to flowing air. After ozone exposure, the rats were given long-term (24 h) memory training which consists of a passive avoidance conditioning. After that the animals were perfused and the brains were placed in the Golgi stain. The analysis consisted in counting the dendritic spines in five secondary and five tertiary dendrites of each of the 20 pyramidal neurons of hippocampus CA1 analyzed. Our results showed alterations on long-term memory and a significant reduction of dendritic spines, and provided evidence that this deterioration in memory is probably due to the reduction in spine density in the pyramidal neurons of hippocampus.

The application of single cell gel electrophoresis or Comet assay to human monitoring studies.

OBJECTIVE: In the search of new human genotoxic biomarkers, the single cell gel electrophoresis assay has been proposed as a sensible alternative. MATERIAL AND METHODS: This technique detects principally single strand breaks as well as alkali-labile and repair-retarded sites. RESULTS: Herein we present our experience using the single cell gel electrophoresis assay in human population studies, both occupationally and environmentally exposed. CONCLUSIONS: We discuss the assay feasibility as a genotoxic biomarker.

High blood lead levels in ceramic folk art workers in Michoacan, Mexico.

Ceramic folk art workers are at risk for developing lead intoxication. These workers live in small settlements, which often lack sanitation services, and these individuals work with ceramics in their homes. The study population comprised individuals of all ages from three rural communities in central Michoacan (Tzintzuntzan, Tzintzunzita, and Colonia Lazaro Cardenas). A survey questionnaire, which was provided to each individual, included questions about household characteristics, presence of a clay oven in the home, and use of lead oxide ("greta") and other hazardous products. Venous blood samples were obtained from the workers. We found lead exposure to be reduced if the home floor was covered and if the house had been painted < or =1 y prior to study. Blood lead levels exceeded the maximum level permitted, but the levels were lower than those found in the 1970s, during which time study techniques for analyzing samples differed from those used in the present study. In addition, activity patterns of the populations differed during the two studies.

DNA damage in leukocytes and buccal and nasal epithelial cells of individuals exposed to air pollution in Mexico City.

There is an increased interest in using biological markers to monitor individuals for possible exposure to environmental toxicants. Test systems which permit the sensitive detection of DNA damage and DNA repair are critically important in such studies. The single cell gel electrophoresis (SCG) assay is a rapid and a sensitive method for the evaluation of DNA damage at the single cell level, providing information on the occurrence of DNA single-strand breaks and alkali labile sites using alkaline conditions. In this study, the differences in the basal level of DNA damage between young adults from the south (exposed principally to high levels of ozone) and young adults from the north (exposed principally to hydrocarbons and particles) of Mexico City were investigated by the SCG assay using three different cell types (leukocytes and nasal and buccal epithelial cells). We found an increased DNA migration in blood leukocytes and nasal cells from individuals who live in the southern part of the city compared to those living in the northern part; however, no differences were observed for buccal epithelial cells. These results show the feasability of using the SCG assay to evaluate DNA damage in different tissues and its great potential for use in the monitoring of humans potentially exposed to genotoxic pollutants.

Metals in lung tissue from autopsy cases in Mexico City residents: comparison of cases from the 1950s and the 1980s.

In autopsies performed on residents of Mexico City during the 1950s and 1980s (45 males and 24 females and 42 males and 42 females, respectively), concentrations of cadmium, copper, cobalt, nickel, and lead in the lungs were studied by atomic absorption spectrometry. Sharp increases were noted in samples taken in the 1980s compared to those from the 1950s. In samples from both time periods, the concentrations were influenced by gender. Smoking was not associated with higher levels of the metals. Only lead seemed to have a relation with age. The enormous differences by gender in the 1950s could be due to different patterns of exposure. The differences among samples from both periods appear to be associated with the increase of air pollutants in the metropolitan areas of Mexico City during the years under study. These results reinforce the importance of studying lung tissue to monitor air pollution by metals.

Risk factors for high levels of lead in blood of schoolchildren in Mexico City.

Risk factors associated with blood lead levels exceeding 15 microg/dl were analyzed in this report. This relatively high lead level was selected because, at the time the study commenced, it was considered to be a "safe" level. A total of 1583 schoolchildren were studied. The students were from (a) two areas in Mexico City (Tlalnepantla and Xalostoc) that have had historically high concentrations of lead in air, and (b) three areas (Pedregal, Iztalpalapa, and Centro) with less impressive air lead levels. Parents were presented with a questionnaire that solicited information about lead risk factors. A bivariate analysis and a multilogistic analysis were conducted to identify associations and to identify the model that most accurately explains the variability of the sample. High blood lead concentrations were found in children who lived in Xalostoc and Tlalnepantla (16.1 and 17.0 microg/dl, respectively), and the lowest concentration (i.e., 10 microg/dl) was found in children from Iztapalapa. The strongest association was with area of residence, followed by education level of parents, cooking of meals in glazed pottery, and chewing or sucking of yellow or other colored pencils. A child's area of residence is the most significant risk factor that must be accounted for when any study of lead and blood lead concentrations is undertaken. Follow-up in similar populations should assist greatly in the evaluation of the impact of governmental actions on public health.

Bronchogenic cancer in patients under 40 years old. The experience of a Latin American country.

Lung cancer in young patients is increasing in frequency, as documented by data from the United States, Canada, Japan, and European countries. However, to date and to our knowledge, there have not been any reports from Latin America on this topic. The published reports show that lung cancer in young patients is associated with smoking habit and family history of lung cancer. Its clinical course seems to be more aggressive than in older patients and the histologic type is less often squamous type. We describe 48 patients, aged 40 years or younger, who were diagnosed as having lung cancer in the Instituto Nacional de Cancerología from 1980 to 1990. The patients were equally divided between men and women. Smoking was documented for only 46 percent of the cases. The histologic type most frequently diagnosed was adenocarcinoma (N = 26) followed by squamous cell carcinoma (N = 12). Almost all the cases (46 cases) were staged IV according to the TNM classification. A group of 33 patients older than 40 years (56 to 82 years) were used for comparison. The differences in sex ratio that were higher for men in the elder (m/f, 2.7:1) were family history for cancer in six patients elder; positive smoking habit in all the aged patients (100 percent) compared with only 43.7 percent in the younger group; histologic type (26 adenocarcinomas and 4 squamous in the younger compared with 14 and 12, respectively, in the elder).