Enzymatic activity induction of GST-family isoenzymes from pesticide mixture used in floriculture.

Glutathione S-transferases (GSTs) comprise a number of genes that codify for a group of isoenzymes that participate in phase II xenobiotic detoxification by means of conjugation with glutathione, producing hydrosoluble compounds. It has been demonstrated that some pesticides are substrates for GST isoenzymes. Floriculture is one of the main economic activities in the municipalities of Villa Guerrero and Atlacomulco; pesticides, applied as mixtures, are intensively used in this activity. In this study, total GST enzymatic activity and glutathione S-transferases theta 1 (GSTT1) enzymatic activity were calculated for a group of floriculture workers exposed to pesticides and for an unexposed group. The former comprised 169 floriculture workers, while the latter, 96 students. The value of the median GST enzymatic activity in the exposed group was 0.560 and 0.169 µmol/min/mL in the unexposed individuals. GSTT1 activity was 1.234 µmol/min/mL in the exposed group and 0.221 µmol/min/mL in the unexposed group. Mann-Whitney U test showed a significant difference between these groups, for both total GST and GSTT1, p < 0.001. Our results show that exposure to pesticides increases the activities of total GST and GSTT1 enzymes.

Congenital malformations according to etiology in newborns from the floricultural zone of Mexico state.

Birth defects are the number one cause of child mortality worldwide and in 2010 it was the second cause in Mexico. Congenital malformations are a public health issue, because they cause infant mortality, chronic disease and disability. The origin can be genetic, environmental or unknown causes. Among environmental contaminants, pesticides stand out. In this study, we determine the frequency and etiology of congenital malformations in newborns (NBs) of a floricultural community and we compare it with that in the urban community. For 18 months, the NBs were monitored at the Tenancingo General Hospital and the Mother and Child Gynecology and Obstetrics Hospital (IMIEM) in Toluca. The identification of these malformations was carried out in accordance with the WHO. In Tenancingo, 1149 NBs were viewed, where 20% had some kind of congenital malformations. While in the IMIEM, 5069 were reviewed and 6% had some malformation. According to the etiology, in Tenancingo, 69% were multifactorial, 28% were monogenetic and 2% were chromosomal. In the IMIEM, 47% were multifactorial, then 18.3% were monogenetic and 2.8% were chromosomal. There was a significant difference between the global frequency of malformations and the multifactorial etiology of both institutions. Our results show that congenital malformations in the NBs occurred more frequently in the floricultural zone and that because the percentage of multifactorial etiology is higher, it is likely there is an association with exposure to pesticides.

In vitro evaluation of the mutagenic and cytostatic effect of Tamaron, Lannate and Manzate alone and in mixture.

Pesticides are often used in agriculture, especially in floriculture. They are frequently applied in binary or ternary mixtures. Nevertheless, their impact on the genetic material has been scarcely explored. In this study, the mutagenic and cytostatic effect of three widely used pesticides, alone and combined, were analyzed. Briefly, lymphocytes cultures were obtained from peripheral blood samples of five healthy donors to determine the sister chromatid exchange and the replicative index (RI). Then, lymphocytes were exposed to Tamaron (100 ppm), Lannate (200 ppm) and Manzate (300 ppm) alone and combined. For the binary mixtures, the concentrations used were 50 ppm of Tamaron, 100 ppm of Lannate and 150 ppm of Manzate. For the ternary mixtures the following concentrations were used: Tamaron (33 ppm), Lannate (70 ppm) and Manzate (100 ppm). Finally, differential staining was performed. It was found that the frequency of SCE/cell showed a significant difference (P ≤ 0.05) between the control (2.66) and the individual treatments of Tamaron (4.87), Lannate: (5.12) and Manzate (4.23). Also, the values of the SCE in the binary mixture of Tamaron+Lannate (5.57), Tamaron+Manzate (6.06) and Lannate+Manzate (6.22) and the ternary mixture (6.63) were statistically different compared to the control. In the RI there was a significant difference between the control (1.98) and the Manzate (1.87). RI differences were also statistically significant (P ≤ 0.05) in mixtures of Tamaron+Lannate (1.64), Tamaron+Manzate (1.63), Lannate+Manzate (1.69) and total mixture (1.53). Therefore, it is suggested that these pesticides alone and in mixtures have both mutagenic and cytostatic synergistic effect in human lymphocytes in vitro.

Polymorphisms in Glutathione S-Transferase M1, T1, and P1 in Patients with Chronic Periodontitis: A Pilot Study.

Background. Although the direct cause of chronic periodontitis is bacterial infection, the progression of this disease depends on genetic and environmental factors, and smoking is a known risk factor in the development and severity of the disease. An individual's susceptibility may be influenced by polymorphisms in the glutathione S-transferase genes. These genes encode enzymes that metabolize xenobiotic compounds. The aim of this study was to determine the frequency of GSTM1, GSTT1, and GSTP1 polymorphisms in Mexicans with chronic periodontitis. Methods. 60 Mexicans with chronic periodontitis (30 smokers and 30 nonsmokers) were studied. A peripheral blood sample was taken for subsequent DNA extraction. The genetic material was PCR-amplified followed by restriction fragment length polymorphism with the aim of identifying GST polymorphisms. Results. Polymorphisms in the GSTT1 and GSTP1 genes were not significantly different between the smokers and nonsmokers. However, there were significant differences (P = 0.05) between groups in polymorphisms in the GSTM1 gene. The patients with chronic periodontitis have a higher frequency of null and mutant polymorphisms in GSTM1, GSTT1, and GSTP1 compared with historical data from a healthy Mexican population. Conclusions. The presence of these polymorphisms may be a risk factor for the development of chronic periodontitis.

Immunotoxic damage in floriculturists exposed to pesticide mixtures.

The aim of the present work was to determine if the use of pesticide mixtures produced alterations in immunotoxicity biomarkers. The study was undertaken in three groups: the first group consisted of 38 floriculturists, the second comprised 38 vendors of the local market, and the last comprised 33 non-exposed persons from another locality. The determinations included haematocrit, mean cellular volume, hemoglobin, number of erythrocytes and leukocytes, immunoglobulins (IgA, IgG, IgM, and IgE), percentage of T-lymphocytes, and mitotic index from lymphocyte cultures with and without phytohaemagglutinin (PHA). The obtained results indicated the following: (i) in the level of the studied immunoglobulins, the results were within the reference values; (ii) there was a reduction in the amount of T-lymphocytes in the floriculturists in comparison with the determined in the other two groups; (iii) there was a decrease in the mitotic index of PHA-stimulated lymphocyte cultures of floriculturists and vendors in relation to the value of the control group; (iv) there was an increase in the mitotic index of unstimulated lymphocytes of floriculturists compared with the lymphocytes of the other two groups; and (v) there was no correlation between the results and the personal characteristics of the studied individuals. Our results established an immunotoxic effect in the floriculturists exposed to pesticides.