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MicroRNAs (miRNAs) are part of the epigenetic mechanisms that regulate gene expression at a post-transcriptional level. This review describes some miRNAs whose expression is modified in obesity and that may be involved in the development of insulin resistance. The metabolic alterations associated with obesity are due to an adipose tissue dysfunction. miRNAs are a mechanism that regulates gene expression, one miRNA can regulate the expression up to a thousand genes, and at the same time one gene can be regulated by several miRNAs; moreover, miRNA expression is tissue specific. Obesity leads to a dysregulation of miRNA expression in adipose tissue, and changes in miRNA expression relate to changes in gene expression related to the development of insulin resistance. However, because miRNA can be exported to the extracellular medium through exosomes, proteins, and lipoproteins, miRNA can be found in extracellular fluids like blood, urine, saliva, and cerebrospinal fluid. Considering the above, miRNA have been proposed as biological markers of different diseases, and also as potential therapeutic targets.

An increase in fat-free mass (FFM) improves athletic performance. The aim of this study was to determine if a decrease in the FFM, expressed as the AKS index, is associated with physiological alterations after a training period in swimmers between 8-15 years old. Forty-two swimmers participated in this study, after 15 weeks of training the swimmers were divided into two groups, those who decreased (A) and those who increased FFM (B). In group A there was a decrease in both, body weight and muscle mass, while in group B there was an increase in body weight. We found that group A showed a reduction in lymphocytes count, in addition to an increase in serum urea, a decrease in VO2, and a decrease in their 1 min recovery. We showed here that a reduction in FFM is positively associated with physiological alterations that reduce athletic performance.

Tissue engineering has been able to develop novel decellularization-recellularization techniques, which facilitates the research for the generation of functional organs. This is based in the initial obtention of the organ's extracellular matrix (ECM). Therefore, any improvement in the decellularization process would have a positive impact in the results of the recellularization process. Nevertheless, commonly the methods and equipment employed for this process are expensive and thus limit the access of this technique to various research groups globally. To develop a decellularization technique with the exclusive use of hydrostatic pressure of detergent solutions, to have an easily accessible and low-cost technique that meets the basic requirements of acellularity and functionality of the ECM. This experimental study was performed in 10 male Wistar rats, obtaining the liver to carry out serial washes, with 1%, 2%, and 3% Triton X-100 solutions and 0.1% SDS. The washes were performed by using a gravity perfusion system (GPS), which assured us a continuous hydrostatic pressure of 7.5 mmHg. The obtained ECM was processed using stains and immunostaining to determine the residual cell content and preservation of its components. The staining showed a removal of cellular and nuclear components of approximately 97% of the acellular ECM, with an adequate three-dimensional pattern of collagen and proteoglycans. Furthermore, the acellular ECM allowed the viability of a primary hepatocyte culture. The use of the GPS decellularization technique allowed us to obtain an acellular and functional ECM, drastically reducing experimentation costs.

The aim of this is study was to analyse the expression of miR-193b, miR-378, miR-Let7-d, and miR-222 in human visceral adipose tissue (VAT), as well as their association with obesity, insulin resistance (IR), and their role in the regulation of genes controlling adipose tissue homeostasis, including adipocytokines, the phosphatase and tension homologue (PTEN), and tumour protein 53 (p53).VAT was obtained from normal-weight (NW), overweight, and obese (OW/OB) subjects with and without IR. Stem-loop RT-qPCR was used to evaluate miRNA expression levels. miRTarBase 4.0, miRWalk, and DIANA-TarBase v8 were used for prediction of validated target gene of the miRNA analysed. A qPCR was used to evaluate PTEN, p53, leptin (LEP), and adiponectin (ADIPOQ) mRNA.miR-222 was lower in IR subjects, and miR-222 and miR-378 negatively correlated with HOMA-IR. PTEN and p53 are miR-222 direct targets according to databases. mRNA expression of PTEN and p53 was lower in OW/OB subjects with and without IR, compared to NW group and its levels positively associated with miR-222. Additionally, p53 and PTEN are positively associated with serum leptin levels. On the other hand, miR-193b and miR-378 negatively correlated with serum leptin but not with mRNA levels. Moreover, miR-Let-7d negatively correlated with serum adiponectin but not with adiponectin mRNA levels.Lower miR-222 levels are associated with IR, and PTEN and p53 expression; the implication of these genes in adipose tissue homeostasis needs more research.

According to the Iodine Global Network, Mexico is considered a country with adequate national iodine intake (297 mg/L), but some regions have not been studied. We aimed to evaluate urinary iodine concentration (UIC) and its association with thyroid stimulating hormone (TSH) levels and the nutritional status in 307 children (aged 5 to 11 years) from three elementary schools of Monterrey, northern Mexico. UIC in spot urine samples and capillary TSH levels were measured to assess thyroid function, in addition to weight, height, body mass index (BMI), and waist circumference (WC). We found a median UIC of 442 mg/L and a significant association between UIC and TSH levels by logistic regression when data were adjusted for (1) age and sex, (2) age, sex, and WC, and (3) age, sex, and weight status. UIC values were higher in 7-year-old children compared to 11-year-old children. High prevalences of overweight/obesity (41%) and WC &gt, 90 pctl (22%) were observed. This study identified higher UIC levels in children than those previously reported in the country. The UIC showed a positive and significant correlation between TSH levels in the three models evaluated. More studies are needed to assess the causes and possible outcomes of high UIC levels.

Aberrant crypt foci (ACF) is the precursor lesion of colorectal carcinogenesis (CRC), one of the most common malignancies in the world. Many studies have reported that people with higher p...

Although cognitive impairment (CI) is classically associated with aging, it has been proposed that neurological pathologies may increase the risk to suffer CI. Despite the evidence of an elevated prevalence of CI in patients with multiple sclerosis (MS), it is not considered among standard clinical evaluations, due the lack of specialists and time required. The aim of this study was to evaluate if lipid profile is associated with cognitive performance in persons with MS. Twenty patients with MS were evaluated. Montreal Cognitive Assessment (MoCA) was employed to determine cognitive performance. CI was observed in 85% of patients, with memory recall and language as the most affected domains. Despite biomarkers were mostly found within reference values, several correlations were observed. MoCA total score was correlated with cholesterol (r = − 0.468, p = 0.037) and LDL (r = − 0.453, p = 0.045). Visuospatial domain was correlated with LDL (r = − 0.493, p = 0.027). Attention domain correlated with triglycerides (r = − 0.455, p = 0.044) and cholesterol (r = − 0.549, p = 0.012). When the person reaches borderline levels of triglycerides, LDL and cholesterol a decrease in cognitive performance can be observed. The mechanism underlying this association has not been established still, it has been proposed that it could be linked with neuroinflammation, alterations in synapses and in the metabolism of amyloid-β protein. This study settles the potential importance that lipid profile could have on cognitive performance in MS. Further studies are needed to establish optimal levels and implication of lipid profile in the diagnosis and monitoring of cognitive performance in Mexican people with MS.

Hormony tarczycy (thyroid hormones, TH) są zaangazowane w wiele roznych procesow biologicznych, wliczając rozwoj ukladu nerwowego, regulacje metabolizmu pośredniego oraz zuzycie energii. Aktywnie uczestniczą w podstawowym zuzyciu energii i termogenezie adaptacyjnej i z tego wzgledu mogą miec wplyw na mase ciala w przebiegu chorob tarczycy. Otylośc to niezakaźna, przewlekla, zapalna choroba metaboliczna, ktora implikuje dodatni bilans energetyczny. Tkanka tluszczowa produkuje szereg hormonow i adipocytokin, takich jak leptyna, ktore mogą wplywac na stan tarczycy na roznych poziomach. Istnieją dowody na to, ze dysfunkcja tarczycy moze predysponowac do otylości i odwrotnie, istnieją dowody sugerujące, ze otylośc powoduje zmiany dotyczące tarczycy. Celem tej pracy bylo opisanie związku miedzy ukladem tarczycy a otylością. Ponadto w pracy zaprezentowano hipotetyczny model podkreślający znaczenie obwodowej dejodynacji hormonow tarczycy i jego role w ustanowieniu dodatniego bilansu energetycznego. Podsumowując, mozemy stwierdzic, ze relacja miedzy ukladem tarczycy a otylością i nadwagą jest zlozona i obejmuje wiele poziomow interakcji. Ponadto, poddając ocenie otylego pacjenta, powinno sie rozwazyc ocene funkcji tarczycy, aby uzyskac lepsze i spersonalizowane efekty leczenia.

Objective This investigation aimed to detect coincidences in the antimicrobial resistance genes (ARG) profiles between members of a group living in a household and to compare them between other groups in order to establish if an exchange of ARG occurs and if dental plaque microbiota can be considered as a source and reservoir of ARG that can be shared between humans and pets. Methods One hundred sixty dental plaque samples were obtained from four groups: Shelter dogs group (n = 20), adult pet owners and dogs group (AD group, n = 40), adult pet owners, children and dogs group (ACD group, n = 60), and adult non-pet owners and children group (AC group, n = 40). DNA was obtained, and specific primers with polymerase chain reaction for ARG detection were used. Results The AD group exhibited the most coincidences in their ARG profiles, 14 (70%) of the 20 profiles coincided in 100% followed by the ACD group with 9 (45%) coincidences. While the AC group was the less coincident group, only 7 (35%) of the 20 profiles coincided. tetM was the most prevalent with 53.1%, followed by tetQ with 52.5% and cfxA with 51.2%, while the less prevalent were tetW with 31.8%, blaTEM-1 with 27.5%, and ermC with 18.7%. Conclusion Dental plaque microbiota can be considered as a source and reservoir of ARG that can be shared between humans and dogs living in a household. The dogs seem to play an important role in the transference of ARG, and the children appear to be the most affected by carrying the most significant number of ARG.

Aberrant crypt foci (ACF) is the precursor lesion of colorectal carcinogenesis (CRC), one of the most common malignancies in the world. Many studies have reported that people with higher phytochemical intake are at a reduced risk of developing ACF. One example of the botanical potential of preventive plant products is

Childhood overweight and obesity are worldwide public health problems and risk factors for chronic diseases. The presence of SNP in several genes has been associated with the presence of obesity. A total of 580 children (8–13 years old) from Queretaro, Mexico, participated in this cross-sectional study, which evaluated the associations of rs9939609 (fat mass obesity-associated (FTO)), rs17782313 (melanocortin 4 receptor (MC4R)) and rs6548238 (transmembrane protein 18 (TMEM18)) SNP with obesity and metabolic risk factors. Overweight and obesity prevalence was 19·8 and 19·1 %, respectively. FTO, MC4R and TMEM18 risk allele frequency was 17, 9·8 and 89·5 %, respectively. A significant association between FTO homozygous and MC4R heterozygous risk alleles and obesity was found (OR 3·9; 95 % CI 1·46, 10·22, and OR 2·1; 95 % CI 1·22, 3·71; respectively). The FTO heterozygous subjects showed higher systolic and diastolic blood pressures, compared with the homozygous for the ancestral allele subjects. These results remain significant after considering adiposity as a covariate. The FTO and MC4R genotypes were not significantly associated with total cholesterol, HDL-cholesterol and insulin concentration. No association was found between TMEM18 risk allele and obesity and/or metabolic alterations. Our results show that, in addition to a higher BMI, there is also an association of the risk genotype with blood pressure in the presence of the FTO risk genotype. The possible presence of a risk genotype in obese children must be considered to offer a more comprehensive therapeutic approach in order to delay and/or prevent the development of chronic diseases.

This chapter highlights the nutritional aspects and phytochemical compounds of fruits and vegetables that confer human health benefits when they are consumed regularly. These diverse compounds include dietary fiber, several minerals, vitamins, and phytochemicals, secondary metabolites that occur naturally in plants and confer biological activities that are able to modulate important cell pathways evidenced by in vitro, animal models, and human studies. Several noncommunicable diseases (such as cancer, obesity, cardiovascular, cognitive, skin, eyes, lung, and bone diseases) can be prevented by regular consumption of fruits and vegetables, based on the inverse relation between their consumption and the risk for developing the disease.

Mexico is considered as a nutritional transition country with a high prevalence of overweight and obesity, and recent studies have reported a high iodine intake in children. Both high iodine intake and obesity have been associated with thyroid dysfunction. Our aim was to assess iodine and salt intake and thyroid function in Mexican schoolchildren with normal weight and obesity. A cross-sectional study was performed during 2012–2013 in schoolchildren from Queretaro, Mexico. Six hundred seventy-eight schoolchildren were evaluated to obtain nutrition status, urinary iodine concentration (UIC) and thyroid volume (TVol). The prevalence of overweight and obesity was 47.3 %, the median UIC was 428 μg/L and TVol was normal in all schoolchildren; however, obese girls had a higher TVol than normal weight at the age of 8, 10 and 12 years. A subsample of schoolchildren was divided in 6–8 and 9–12-year-old groups, in order to compare thyroid function (thyrotropin, free T4, and anti-thyroid antibodies); iodine and salt intake were estimated with 24-h urinary samples. No differences in thyroid function were observed in both age groups. In the 6–8-year-old group, obese schoolchildren had higher iodine intake than normal-weight children (415.5 vs. 269.1 μg/day, p

Hormony tarczycy (thyroid hormones, TH) są zaangażowane w wiele różnych procesów biologicznych, wliczając rozwój układu nerwowego, regulację metabolizmu pośredniego oraz zużycie energii. Aktywnie uczestniczą w podstawowym zużyciu energii i termogenezie adaptacyjnej i z tego względu mogą mieć wpływ na masę ciała w przebiegu chorób tarczycy. Otyłość to niezakaźna, przewlekła, zapalna choroba metaboliczna, która implikuje dodatni bilans energetyczny. Tkanka tłuszczowa produkuje szereg hormonów i adipocytokin, takich jak leptyna, które mogą wpływać na stan tarczycy na różnych poziomach. Istnieją dowody na to, że dysfunkcja tarczycy może predysponować do otyłości i odwrotnie, istnieją dowody sugerujące, że otyłość powoduje zmiany dotyczące tarczycy. Celem tej pracy było opisanie związku między układem tarczycy a otyłością. Ponadto w pracy zaprezentowano hipotetyczny model podkreślający znaczenie obwodowej dejodynacji hormonów tarczycy i jego rolę w ustanowieniu dodatniego bilansu energetycznego. Podsumowując, możemy stwierdzić, że relacja między układem tarczycy a otyłością i nadwagą jest złożona i obejmuje wiele poziomów interakcji. Ponadto, poddając ocenie otyłego pacjenta, powinno się rozważyć ocenę funkcji tarczycy, aby uzyskać lepsze i spersonalizowane efekty leczenia.

Axonal projection is controlled by discrete regions localized at the neuroepithelium, guiding the neurite growth during embryonic development. These regions exert their effect through the expression of a family of chemotropic molecules, which actively participate in the formation of neuronal connections of the central nervous system in vertebrates. Previous studies describe prosomere 1 (P1) as a possible organizer of axonal growth of the rostral rhombencephalon, contributing to the caudal projection of reticulospinal rhombencephalic neurons. This work studies the contribution of chemotropic signals from P1 or pretectal medial longitudinal fascicle (MLF) neurons upon the caudal projection of the interstitial nuclei of Cajal (INC). By using in ovo surgeries, retrograde axonal labeling, and immunohistochemical techniques, we were able to determine that the absence of P1 generates a failure in the INC caudal projection, while drastically diminishing the reticulospinal rhombencephalic neurons projections. The lack of INC projection significantly decreases the number of reticulospinal neurons projecting to the MLF. We found a 48.6% decrease in the projections to the MLF from the rostral and bulbar areas. Similarly, the observed decrease at prosomere 2 was 51.5%, with 61.8% and 32.4% for prosomeres 3 and 4, respectively; thus, constituting the most affected rostral regions. These results suggest the following possibilities: i, that the axons of the reticulospinal neurons employ the INC projection as a scaffold, fasciculating with this pioneer projection; and ii, that the P1 region, including pretectal MLF neurons, exerts a chemotropic effect upon the INC caudal projection. Nonetheless the identification of these chemotropic signals is still a pending task.

Background Multiple sclerosis (MS) is one of the principal causes of non-traumatic neurological disability among young adults. The unpredictable and progressive evolution of multiple sclerosis is associated with a decline in physical and psychological health, affecting quality of life, which may be influenced by additional physical and psycho-social factors. Objective The present investigation aims to evaluate the quality of life (QoL), use of coping strategies and their relationship with other physical and psycho-social factors among 26 Mexican persons with MS. Methods Eight questionnaires were administrated for evaluation of the additional psycho-social and physical factors, including quality of life, coping strategies, social support system, family functionality, depression and anxiety prevalence. Results Results showed that the use of positive coping strategies (84.6% of our population) improve QoL perception (r = 0.396, p = 0.045) and the following domains: physical health (r = 0.514, p = 0.009), psychological health (r = 0.516, p = 0.008), social relationships (r = 0.654, p = 0.000) and environment (r = 0.600, p = 0.002). Negative correlations were observed between QoL and the presence of symptoms of both depression (r = −0.557, p = 0.003) and anxiety (r = −0.517, p = 0.007). A multiple linear regression model showed that QoL can be explained by physical and psycho-social factor in 54.6% of the cases that were evaluated. Conclusion The use of positive coping strategies in conjunction with a suitable psycho-social environment and good physical health result in a better perception of QoL in Mexican patients living with MS. Still, the negative factors are ineffectively diagnosed and hence generally under treated in medical MS monitoring. An interdisciplinary evaluation will provide the adequate tools to confront the diagnosis and the uncertainty of multiple sclerosis evolution, benefiting the QoL of Mexican patients with MS.

Several epidemiological studies have suggested that carotenoids have antineoplasic activities. The objective of this study was to determine the antiproliferative effect of rich carotenoid lipophilic extracts of papaya fruit pulp ( Carica papaya L., cv Maradol) in breast cancer cells, MCF-7 (estrogen receptor positive) and MDA-MB-231 (estrogen receptor negative), and in non-tumoral mammary epithelial cells MCF-12F. Antiproliferative effect was evaluated using the methylthiazolydiphenyl-tetrazolium bromide (MTT) assay and testing lipophilic extracts from different papaya fruit ripening stages (RS1, RS2, RS3, RS4), at different times (24, 48 and 72 h). Papaya lipophilic extracts do not inhibit cell proliferation of MCF-12F and MDA-MB-231 cells. However, MCF-7 cells showed a significant reduction in proliferation at 72 h with the RS4 papaya extract. Results suggested that lipophilic extracts had different action mechanisms on each type of cells and therefore, more studies were required to elucidate such mechanisms.

AIM To assess if the included vascular endothelial growth factor (VEGF) polymorphisms rs3025035, rs3025021 and rs2010963 are associated to proliferative retinopathy in a Mexican population with type 2 diabetes mellitus (T2DM). METHODS A case-control study was conducted in adult individuals with T2DM associated to proliferative retinopathy or non-proliferative retinopathy from Oct. 2014 to Jun. 2015 from the Retina Department of the Asociation to Prevent Blindness in Mexico. The selected patients were adults with a diagnosis of T2DM ≥5y. All subjects had a comprehensive ocular examination and the classification of the retinopathy severity was made considering the Early Treatment Diabetic Retinopathy Study (ETDRS) standardization protocols. Genomic DNA was extracted from whole fresh blood. All samples were genotyped by qPCR for selected VEGF polymorphisms. Hardy-Weinberg equilibrium was calculated by comparing Chi-square values between the expected and the observed values for genotype counts. RESULTS In total 142 individuals were enrolled, 71 individuals with T2DM and associated proliferative retinopathy and 71 individuals with non-proliferative retinopathy. One-sided Fisher's exact test was performed for rs3025021 [OR (95% CI)=0.44(0.08-2.2); P=0.25] and rs2010963 [OR (95% CI)=0.63(0.25-1.6); P=0.23]. The minor allelic frequencies obtained were 26% for rs3025021, 10% for rs3025035 and 61% for rs2010963. The pairwise linkage disequilibrium between the three SNP was assessed, and was as follows: rs3025021 vs rs3025035: D'=1.0, r2=0.1043, P≤0.0001; rs3025021 vs rs2010963: D'=0.442, r2=0.0446, P=0.149; rs3025035 vs rs2010963: D'=0.505, r2=0.0214, P=0.142. CONCLUSION This is the first analysis involving VEGF polymorphisms and proliferative diabetic retinopathy in a Mexican population. A major finding of the present study is that none of the polymorphisms studied was significantly associated with proliferative retinopathy. Based on these results, we can infer that different populations have different associations for the same polymorphisms.

Childhood overweight and obesity are worldwide public health problems and risk factors for chronic diseases. The presence of SNP in several genes has been associated with the presence of obesity. A total of 580 children (8-13 years old) from Queretaro, Mexico, participated in this cross-sectional study, which evaluated the associations of rs9939609 (fat mass obesity-associated (

Background: The antioxidant function of iodine and iodine deficiency as a risk factor of preeclampsia have been previously reported. Aim: To analyze the association between iodine deficiency, oxidative stress and antioxidant status with hypertensive disease of pregnancy (HPD). Method: Fifty-seven pregnant women were recruited in the last trimester of pregnancy; 20 were diagnosed with hypertensive disease (HPD) of pregnancy and 37 were normotensive pregnant women. Urinary iodine concentration (UIC), TSH, free T4 (fT4), total antioxidant status (FRP), superoxide dismutase (SOD), catalase (CAT), and oxidative stress (TBARS) were evaluated by colorimetric methods. Results: UIC median for all pregnant women was 151.9 µg/l. The UIC for pregnant women with HPD was 50-149 µg/l, compared to 150-249 µg/l in normotensive women. No significant differences in levels of TSH and fT4 in normotensive pregnant compared with HPD women were found. Pregnant women with HPD had significant high levels of TBARS, and significant low levels of FRP, SOD, CAT and UIC compared to normotensive pregnant. In addition, pregnant women with optimal levels of UIC had a higher SOD activity (r = 0.354, p = 0.011), while iodine deficiency was associated with HPD (r = -0,281, p = 0.039). Similarly, pregnant women with HPD had a significant negative association with SOD activity (r = -0.702, p = 0.005), CAT (r = -0.409, p = 0.002), and FRP (r = -0.624, p = 0.003), and a positive association with TBARS (r = 0.744, p = 0.001). Conclusion: Iodine contributes to redox balance during pregnancy; its deficiency is associated with HPD. This study shows the importance of iodine during pregnancy.

Consumption of fruits and vegetables has been associated with reduced risk of chronic diseases. They are rich in several antioxidant phytochemicals such as carotenoids and phenolic compounds that could be responsible for the health benefits. We studied the antineoplastic properties of some fruits and vegetables using in vivo and in vitro models. First, we studied the effect of ‘Ataulfo’ mango consumption on chemically-induced mammary carcinogenesis and plasma antioxidant capacity (AC) in rats treated with the carcinogen N-methyl-Nnitrosourea (MNU). Mango was administered in the drinking water (0.02-0.06 g/ml) during both short-term and long-term periods to rats, and plasma antioxidant capacity was measured by ferric reducing/antioxidant power (FRAP) and total oxyradical scavenging capacity assays. Mango consumption did not have an effect on mammary carcinogenesis (incidence, latency and number of tumors), nor on plasma AC of rats treated with MNU. Second, we screened using methylthiazolydiphenyltetrazolium bromide assay the antiproliferative activity of aqueous extracts of avocado, black sapote, guava, mango, cactus cladodes (cooked and raw), papaya, pineapple, four different prickly pear fruit, grapes and tomato, on the breast cancer cell line MCF-7. β-carotene, gallic acid, total phenolic contents and AC were analyzed in each aqueous extract. In vitro study showed that only the papaya extract had a significant antiproliferative effect and we did not notice a relationship between total phenolic content and AC with antiproliferative effect. These results suggested that each plant food has a unique combination in quantity and quality of phytochemicals which could determine its biological activity.

Breast carcinoma-derived MCF-7 cells are frequently used in biomedical research. However, few reports exist regarding the characterization of signaling mechanisms in these cancerous cells involved in intracellular Ca(2+) dynamics. Consequently, the aim of these experiments was to characterize the ryanodine receptor/Ca(2+) release channel (RyR) present in MCF-7 cells. Ryanodine (100 nM), cADPR (5 microM), and caffeine (10 mM) promoted cytoplasmic Ca(2+) mobilization; in contrast, ryanodine at inhibitory concentration (100 microM) decreased the basal Ca(2+) level. Fluorescent probes demonstrated that RyR is located mainly in endomembranes. Some degree of co-localization with inositol trisphosphate receptor (IP(3)R) was observed, whereas coincidence with thapsigargin-sensitive Ca(2+)-ATPase (SERCA) was more limited. Molecular cloning resulted in the detection exclusively of RyR isoform 1. For the first time, it is shown that MCF-7 cells express functional RyR.

We analyzed the effect of molecular iodine (I2), potassium iodide (KI) and a subclinical concentration of thyroxine (T4) on the induction and promotion of mammary cancer induced by N-methyl-N-nitrosourea. Virgin Sprague-Dawley rats received short or continuous treatment. Continuous I2 treated rats exhibited a strong and persistent reduction in mammary cancer incidence (30%) compared to controls (72.7%). Interruption of short or long term treatments resulted in a higher incidence in mammary cancer compared to the control groups. The protective effect of I2 was correlated with the highest expression of the I-/Cl- transporter pendrin and with the lowest levels of lipoperoxidation expression in mammary glands. Triiodothyronine serum levels and Na+/I- symporter, lactoperoxidase, or p53 expression did not show any changes. In conclusion continuous I2 treatment has a potent antineoplastic effect on the progression of mammary cancer and its effect may be related to a decrease in the oxidative cell environment.

Thyroid hormones participate in the regulation of growth, development and energy expenditure of vertebrates. Type I (D1) and type II 5'deiodinases catalyze the peripheral conversion of the thyroid prohormone thyroxine to the active form triiodothyronine (T3). D1 is expressed in organs like liver, thyroid, and lactating mammary gland. This enzyme is regulated in an organ-specific manner by a wide number of factors like carbohydrates, T3, thyrotropin, and catecholamines. However, it has been shown that in several types of cancer the expression of D1 is reduced, lost, or regulated by different components. In the present work we describe the expression and regulation of 5'deiodinases in two breast cancer cell lines: MCF-7 (ovarian hormone-dependent) and MDA-MB-231 (ovarian hormone-independent). Our results showed that MCF-7 cells expressed D1 activity ( approximately 10 pmol I(-)/mg protein per h), which was stimulated only by retinoic acid treatments, but not by T3 or the beta-adrenergic agonist isoproterenol. In MDA-MB-231 cells, deiodinase activity was not detected in control conditions nor under any of these treatments. These results support the notion that D1 expression could represent a sensitive differentiation marker.

Iodine is an essential constituent of thyroid hormones (TH). TH actively take part in critical periods of brain development during embryonic, fetal and postnatal stages. Therefore the absence of TH or iodine in these critical periods produces an irreversible brain damage. In fact, it is known that iodine deficiency is the leading cause of preventable brain damage worldwide. Because of the physiological adjustments during pregnancy iodine requirements increase significantly from 150 microg per day in non-pregnant adult women to 250 microg per day. Moreover, recent epidemiological studies around the world show that iodine intake during pregnancy is insufficient in many countries, even in developed countries like Australia, Spain and Italy. In the present work an overview of the importance of iodine nutrition during pregnancy is given.

OBJECTIVE. To examine the prevalence of abnormal thyroid function tests and positive anti-thyroid antibodies in two Central Mexican cities. MATERIAL AND METHODS. Subjects 18 to 70 years old were randomly selected to participate in this survey. A questionnaire was given and blood samples were taken to measure TSH and free T4 levels as well as anti-TPO and anti- Tg antibodies. RESULTS. The mean TSH level in subjects without existing thyroid disease was 1.72 mIU/L; 0.64 and 3.74 mIU/L were the 2.5th and 97.5th percentiles. The mean free T4 level was 1.02 ng/dL, and the 2.5th and 97.5th percentiles were 0.78 and 1.31 ng/dL, respectively. There was a 2.5% prevalence of former diagnosed thyroid diseases, 3.9% of individuals were sub-hypo, and 1.1% had overt hypothyroidism. Total hypothyroidism prevalence was 7.48% (when we considered TSH levels greater than 4.5 mIU/L), but it was 11.03% when diagnosed with TSH values greater than 3.5 mIU/L. Factors associated with hypothyroidism were older age, positive family background of thyroid disease, and positive anti- TPO and anti-Tg antibodies. Subclinical and overt hyperthyroidism were found in 1.7% of participants. CONCLUSIONS. Abnormal thyroid function test prevalence in this population was high, but few participants were aware of having a thyroid disease. The prevalence of positive anti-thyroid antibodies was high. More studies are necessary to elucidate the effects of thyroid abnormalities on other aspects of health status and quality of life.

OBJECTIVE AND METHODS: To estimate median urinary iodine concentration (UIC), and to correlate it with global nutrition indicators and social gap index (SGI) in 50 elementary state schools from 10 municipalities in the State of Queretaro, Mexico. RESULTS: 1,544 students were enrolled and an above of requirements of iodine intake was found (median UIC of 297 µg/L). Iodine status was found as deficient, adequate, more than adequate and excessive in 2, 4, 19 and 25 schools, respectively. Seventy seven percent of table salt samples showed adequate iodine content (20-40 ppm), while 9.6% of the samples had low iodine content (< 15 ppm). Medians of UIC per school were positively correlated with medians of body mass index (BMI) by using the standard deviation score (SDS) (r = 0.47; p < 0.005), height SDS (r = 0.41; p < 0.05), and overweight and obesity prevalence (r = 0.41; p < 0.05). Medians of UIC per school were negatively correlated with stunting prevalence (r = -0.39; p = 005) and social gap index (r = -0.36; p < 0.05). Best multiple regression models showed that BMI SDS and height were significantly related with UIC (p < 0.05). CONCLUSIONS: There is coexistence between the two extremes of iodine intake (insufficient and excessive). To our knowledge, the observed positive correlation between UIC and overweight and obesity has not been described before, and could be explained by the availability and consumption of snack food rich in energy and iodized salt. OBJETIVO E MÉTODOS: Estimar a concentração de iodo urinário (CIU) mediana e correlacioná-la com os indicadores de nutrição geral e com o índice de desigualdade social (IDS) de 50 escolas estaduais de ensino fundamental de 10 municípios do estado de Querétaro, no México. RESULTADOS: Utilizou-se um total de 1.544 crianças e encontrou-se uma ingestão acima das necessidades de iodo (CIU mediana de 297 µg/L). O nível de iodo determinado foi deficiente, adequado, mais do que adequado e excessivo em 2, 4, 19 e 25 escolas, respectivamente. Setenta e sete por cento de amostras de sal de mesa mostraram uma quantidade de iodo adequada (20-40 ppm), enquanto 9,6% das amostras tinham um teor de iodo baixo (< 15 ppm). As medianas de CIU por escola foram correlacionadas positivamente com as medianas do índice de massa corporal (IMC) usando o desvio-padrão da contagem (DP) (r = 0,47; p < 0.005), o DP da altura (r = 0,41; p < 0.05) e a prevalência de sobrepeso e de obesidade (r = 0,41; p < 0,05). As medianas de CUI por escola foram correlacionadas negativamente com a prevalência de desnutrição (r = -0.39; p = 005) e com o índice de desigualdade social (r = -0.36; p < 0,05). Os melhores modelos de regressão múltipla mostraram que a DP do IMC e a altura foram relacionados significativamente com a CIU (p < 0,05). CONCLUSÃO: Existe uma convivência entre os dois extremos de ingestão de iodo (insuficiente e excessiva). Em nosso conhecimento, a correlação positiva entre a CIU, o excesso de peso e a obesidade não foi descrita anteriormente e poderia ser explicada pela disponibilidade e consumo de alimentos ou refeições ricos(as) em energia e sal iodado.

The tight junctions are critical for the sealing of cellular sheets and controlling paracellular ion flux. Tight junctions are composed primarily of 3 components: The IgG-like family of junctional adhesion molecules (JAMs), occluding and claudin families. Claudins are the main constituents of tight junctions. The claudin family proteins is composed of approximately 24 transmembrane proteins, all of which are closely related, most of them are well characterized at the level of gene and protein. The claudins are present in variety of normal tissues, hyperplastic conditions, but have also been found in benign neoplams and cancers that exhibit epithelial differentiation. Loss of claudins expression has been reported in various malignant diseases. The differential expression of several members of the family of the claudins in various cancers has been used to confirm the histological identity of certain types of cancer.

Different iodinated mouse obestatin peptides have been characterized toward their in vitro stability in the main metabolic compartments plasma, liver and kidney. Using HPLC-UV for quantification, significant differences in the degradation kinetics of the iodinated peptides, arising from both enzymatic proteolysis and dehalogenation, were found when compared to the native, unmodified peptide. HPLC-MS/MS analysis demonstrated that the cleavage sites were dependent upon the biological matrix and the location of the amino acid residue incorporating the iodine atom(s). The degrading proteases were found to target peptide bonds further away from the iodine incorporation, while proteolytic cleavages of nearby peptide bonds were more limited. Diiodinated amino acid residue containing peptides were found to be more susceptible to deiodination than the mono-iodinated derivative. In plasma, the percentage of peptide degradation solely attributed to deiodinase activity after 20 min incubation reached up to 25% for 2,5-diiodo-H(19)-obestatin compared to 20% and only 3% for (3,5-diiodo-Y(16))- and (3-iodo-Y(16)) obestatin, respectively. Hence, our results demonstrate that the different iodinated peptides pose significantly different metabolization properties and thus, also different biological activities are expected for peptides upon iodination.

Iodine nutrition during pregnancy has become an important public health concern because of the deleterious impact of iodine deficiency on brain development during fetal and early postnatal life. Iodine nutrition status can be assessed in a population by the median urinary iodine concentration (UIC). World Health Organization, the United Nations Children's Fund, and the International Council for Iodine Deficiency Disorders have established that a median of UIC between 150 and 249 μg/L in pregnant women indicates an adequate iodine intake. The aim of this study was to assess iodine nutrition status in Mexican pregnant women.Two hundred ninety-four pregnant women receiving prenatal care in the Public Medical Units of the State Ministry of Health for each pregnancy trimester (first, n=60; second, n=103; and third, n=131) in Queretaro, Mexico, were enrolled to assess UIC by the Sandell-Kholtoff method.The median of UIC was 273, 285, and 231 μg/L in the first, second, and third trimesters of gestation, respectively. Globally, the median (range) of UIC was 260 (5-1320) μg/L, and the percentage of samples with UIC below 150 μg/L was 28%. There was no significant difference between the UIC of women using iodine-containing multivitamins compared with those who reported the consumption of noniodized multivitamins (p0.05). In addition, we found no difference between the UIC of women using iodized table salt compared with those who employed noniodized table salt, with those who did not know whether their table salt was iodized (p0.05).Based on the median UIC, iodine intake in Queretaro, Mexico, is slightly above requirements during the first two trimesters, and adequate in the third trimester. The wide Mexican universal iodized salt program seems to supply adequate dietary iodine to pregnant women without health insurance in this region. However, regular monitoring of iodine status is recommended during pregnancy throughout Mexico.

Iodide is a trace element and a key component of thyroid hormones (TH). The availability of this halogen is the rate-limiting step for TH synthesis; therefore, thyroidal iodide uptake and recycling during TH synthesis are of major importance in maintaining an adequate supply. In the rat, the thyroid gland co-expresses a distinctive pair of intrathyroidal deiodinating enzymes: the thyroid iodotyrosine dehalogenase (tDh) and the iodothyronine deiodinase type 1 (ID1). In the present work, we studied the activity of these two dehalogenases in conditions of hypo- and hyperthyroidism as well as during acute and chronic iodide administration in both intact and hypophysectomized (HPX) rats. In order to confirm our observations, we also measured the mRNA levels for both dehalogenases and for the sodium/iodide symporter, the protein responsible for thyroidal iodide uptake. Our results show that triiodothyronine differentially regulates tDh and ID1 enzymatic activities, and that both acute and chronic iodide administration significantly decreases rat tDh and ID1 activities and mRNA levels. Conversely, both enzymatic activities increase when intrathyroidal iodide is pharmacologically depleted in TSH-replaced HPX rats. These results show a regulatory effect by iodide on the intrathyroidal dehalogenating enzymes and suggest that they contribute to the iodide-induced autoregulatory processes involved in the Wolff-Chaikoff effect.

We evaluated the antiproliferative effect of aqueous extracts of 14 plant foods consumed in Mexico on the breast cancer cell line MCF-7. The plant foods used were avocado, black sapote, guava, mango, prickly pear cactus stems (called nopal in Mexico, cooked and raw), papaya, pineapple, four different cultivars of prickly pear fruit, grapes and tomato. β-Carotene, total phenolics and gallic acid contents and the antioxidant capacity, measured by the ferric reducing/antioxidant power and the 2,2-diphenyl-1,1-picrylhydrazyl radical scavenging assays, were analyzed in each aqueous extract. Only the papaya extract had a significant antiproliferative effect measured with the methylthiazolydiphenyl-tetrazolium bromide assay. We did not notice a relationship between the total phenolic content and the antioxidant capacity with antiproliferative effect. It is suggested that each extract of plant food has a unique combination of the quantity and quality of phytochemicals that could determine its biological activity. Besides, papaya represents a very interesting fruit to explore its antineoplastic activities.

Introduction Studies in mammary cancer demonstrated that moderately high concentrations of molecular iodine (I2) have a antiproliferative and apoptotic effect either in vivo as in vitro, however the cellular intermediated involved in these effects has not been elucidated. Methods Virgin Sprague-Dawley rats were treated with methyl-nitrosourea (MNU: single dose ip, 50 mg/Kg bw) and the participation of arachidonic acid (AA) and PPAR receptors in the antineoplasic effect of I2 where analyzed. Results I2-treated rats for four weeks exhibited a significant reduction in the incidence (62.5 vs. 100%) and size (0.87 ± 0.98 vs 1.96 ± 1.5 cm3) of mammary tumors. HPLC analysis showed that tumoral but not normal mammary tissue contained an elevated basal concentration of AA and significantly more AA-iodinated called 6-iodolactone (6-IL) after chronic I2 treatment. Tumors from I2-treated rats showed fewer cells positive to proliferating cell nuclear antigen, lower blood vessel density, as well as decreases in vascular endothelial growth factor, urokinase-type plasminogen activator, and PPAR type alpha (PPARα). These same tumors showed increases in the cell death markers, TUNEL-positive cells (p < 0.05) and the enzyme caspase-3 (trend), as well as significant induction of PPAR type gamma (PPARγ). Conclusion Together, these data demonstrate that the antineoplasic effect of iodine involves 6-IL formation and PPARγ induction.

Several studies have demonstrated that moderately high concentrations of molecular iodine (I(2)) diminish the symptoms of mammary fibrosis in women, reduce the occurrence of mammary cancer induced chemically in rats (50-70%), and have a clear antiproliferative and apoptotic effect in the human tumoral mammary cell line MCF-7. Nevertheless, the importance of these effects has been underestimated, in part because of the notion that exposure to excess iodine represents a potential risk to thyroid physiology. In the present work we demonstrate that uptake and metabolism of iodine differ in an organ-specific manner and also depend on the chemical form of the iodine ingested (potassium iodide vs. I(2)). Further, we show that a moderately high I(2) supplement (0.05%) causes some of the characteristics of the "acute Wolff-Chaikoff effect"; namely, it lowers expression of the sodium/iodide symporter, pendrin, thyroperoxidase (TPO), and deiodinase type 1 in thyroid gland without diminishing circulating levels of thyroid hormone. Finally, we confirm that I(2) metabolism is independent of TPO, and we demonstrate that, at the doses used here, which are potentially useful to treat mammary tumors, chronic I(2) supplement is not accompanied by any harmful secondary effects on the thyroid or general physiology. Thus, we suggest that I(2) could be considered for use in clinical trials of breast cancer therapies.