Leukocyte Telomere Length Predicts Severe Disability in Relapsing-Remitting Multiple Sclerosis and Correlates with Mitochondrial DNA Copy Number.

Multiple sclerosis (MS) is a chronic autoimmune inflammatory disease that affects the nervous system. Peripheral blood leukocyte telomere length (LTL) and mitochondrial DNA copy number (mtDNA-CN) are potential biomarkers of neurological disability and neural damage. Our objective was to assess the LTL and mtDNA-CN in relapsing-remitting MS (RRMS). We included 10 healthy controls, 75 patients with RRMS, 50 of whom had an Expanded Disability Status Scale (EDSS) from 0 to 3 (mild to moderate disability), and 25 had an EDSS of 3.5 to 7 (severe disability). We use the Real-Time Polymerase Chain Reaction (qPCR) technique to quantify absolute LTL and absolute mtDNA-CN. ANOVA test show differences between healthy control vs. severe disability RRMS and mild-moderate RRMS vs. severe disability RRMS (p = 0.0130). LTL and mtDNA-CN showed a linear correlation in mild-moderate disability RRMS (r = 0.378, p = 0.007). Furthermore, we analyzed LTL between RRMS groups with a ROC curve, and LTL can predict severe disability (AUC = 0.702, p = 0.0018, cut-off < 3.0875 Kb, sensitivity = 75%, specificity = 62%), whereas the prediction is improved with a logistic regression model including LTL plus age (AUC = 0.762, p = 0.0001, sensitivity = 79.17%, specificity = 80%). These results show that LTL is a biomarker of disability in RRMS and is correlated with mtDNA-CN in mild-moderate RRMS patients.

Phylogenomic analysis and Mycobacterium tuberculosis antibiotic resistance prediction by whole-genome sequencing from clinical isolates of Caldas, Colombia.

Mycobacterium tuberculosis (M. tuberculosis) was the pathogen responsible for the highest number of deaths from infectious diseases in the world, before the arrival of the COVID-19 pandemic. Whole genome sequencing (WGS) has contributed to the understanding of genetic diversity, the mechanisms involved in drug resistance and the transmission dynamics of this pathogen. The object of this study is to use WGS for the epidemiological and molecular characterization of M. tuberculosis clinical strains from Chinchiná, Caldas, a small town in Colombia with a high incidence of TB. Sputum samples were obtained during the first semester of 2020 from six patients and cultured in solid Löwenstein-Jensen medium. DNA extraction was obtained from positive culture samples and WGS was performed with the Illumina HiSeq 2500 platform for subsequent bioinformatic analysis. M. tuberculosis isolates were typified as Euro-American lineage 4 with a predominance of the Harlem and LAM sublineages. All samples were proven sensitive to antituberculosis drugs by genomic analysis, although no phenotype antimicrobial tests were performed on the samples, unreported mutations were identified that could require further analysis. The present study provides preliminary data for the construction of a genomic database line and the follow-up of lineages in this region.

Nrf2-Mediated Antioxidant Activity of the inner bark extracts obtained from Tabebuia rosea (Bertol) DC and Tabebuia chrysantha (JACQ) G. Nicholson.

Background: Several ethnobotanical and ethnopharmacological studies have shown the therapeutic potential of plants from the genus Tabebuia, which have long been used in traditional medicine in rural areas of South America, for the treatment of several human diseases. This study aimed to evaluate the Nrf2-mediated antioxidant activity of the inner bark extracts obtained from Tabebuia rosea and Tabebuia chrysantha. Methods: The antioxidant activity of extracts obtained from the inner bark of T. rosea and T. chrysantha was evaluated using the Oxygen radical absorbance capacity (ORAC) technique. The effect of extracts on the viability of HepG2 cells was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method. The translocation of Nrf2 to the nucleus after exposure of HepG2 cells to the extracts and controls (α-lipoic acid, curcumin and hydrogen peroxide) was evaluated using the Nrf2 transcription factor kit. Induction of the Nrf2-mediated antioxidant response gene ( NQO1) was evaluated by real-time PCR. Results: The ethyl acetate extract obtained from both species displayed the highest ORAC activity (12,523 and 6,325 µmoles Eq Trolox/g extract). In addition, the extracts had the ability to activate and to translocate Nrf2 to the nucleus, as well as to induce the expression of NQO1. Conclusion: These results indicate that the ethyl acetate extracts obtained from the inner bark of T. chrysantha and T. rosea have an important antioxidant effect mediated by Nrf2 activation, and could be used as a new source of natural antioxidants.

Association of Paraoxonase-1 Q192R (rs662) Single Nucleotide Variation with Cardiovascular Risk in Coffee Harvesters of Central Colombia.

Paraoxonase 1 (PON1), a high-density lipoprotein-associated antioxidant enzyme, hydrolyzes several organophosphate pesticides and oxidized lipids. The PON1 Q192R polymorphism affects the catalytic efficiency and is considered a risk factor for pesticide intoxication and cardiovascular disease (CVD) but the association is not consistent between individuals or populations. We aimed to study the association of PON1 Q192R polymorphism with CVD risk in coffee harvesters of central Colombia. Demographics were collected from 205 subjects via standardized questionnaires. Lipid profiles and serum butyrylcholinesterase (BChE) were measured by standard procedures. The calculated 10-year atherosclerotic CVD (ASCVD) risk was used as the cardiovascular risk estimate. Q192R genotype was determined by real-time PCR. Prevalence of hypertension, hypercholesterolemia, and the 10-year ASCVD risk was 33%, 62%, and 22%, respectively. BChE levels were no indicative of recent pesticide exposure, although a positive correlation was observed with BChE and hypercholesterolemia. The Q192R genotype frequencies were 38% (QQ), 44% (QR), and 18% (RR). We found an association of the 192Q genotype with hypertension. The results of this study signal the importance to evaluate the influence and potential interactions of BChE and PON1 192Q allele with known genetic and environmental factors implicated in the pathogenesis of CVD.

Short (GT)n microsatellite repeats in the heme oxygenase-1 gene promoter are associated with antioxidant and anti-inflammatory status in Mexican pediatric patients with sepsis.

An adequate immune and antioxidant response is a key to the resolution of sepsis. Heme oxygenase-1 (HMOX1) is a stress protein with a polymorphic (GT)n repeat in its gene promoter that regulates its expression in response to oxidative injury, such as that present in sepsis. HMOX1 is the rate-limiting enzyme of heme degradation, and the heme breakdown products, CO, Fe, and bilirubin, are considered to be biologically active metabolites with direct or indirect antioxidant and anti-inflammatory properties. In this study, we investigated the inflammatory and antioxidant response and the relationship with the HMOX1 levels and HMOX1 polymorphism in Mexican septic pediatric patients. In a case-control pilot study, we enrolled 64 septic patients and 72 hospitalized control patients without a diagnosis of sepsis. DNA extracted from buffy coat was genotyped for HMOX1 (GT)n polymorphism by PCR and markers of antioxidant and inflammatory status were quantified in plasma by analysis of the oxygen radical absorbance capacity (ORAC), protein carbonyl (PC), interleukin (IL) 6, IL10, and HMOX1 levels. In septic children, oxidative and inflammatory markers were elevated, and HMOX1 levels were positively correlated with IL10 levels. Genotypic and allelic distribution of HMOX1 polymorphism showed no difference between groups. HMOX1 short-allele septic carriers (< 25 GT repeats) presented favorable ORAC, PC and IL10 levels. This study confirms that an active response against pediatric sepsis involves the expression of HMOX1 and IL10, suggesting that the high antioxidant status associated with HMOX1 short-allele septic carriers might provide a beneficial environment for sepsis resolution.

Modulation of antioxidant defense system after long term arsenic exposure in Zantedeschia aethiopica and Anemopsis californica.

Zantedeschia aethiopica (calla lily) and Anemopsis californica (yerba mansa) are plant species capable of accumulating arsenic (As) and therefore proposed as phytoremediation for removal of As from drinking water. The effects of a continuous 6 month As exposure (34±11 µg/L) from local contaminated groundwater on the antioxidant response of Z. aethiopica and A. californica were evaluated in leaves and stems of the plants bimonthly in a subsurface flow constructed wetland. As increased the activities of the antioxidant enzymes ascorbate peroxidase, glutathione reductase and catalase where higher levels were observed in Z. aethiopica than A. californica. No significant differences were detected on lipid peroxidation levels or antioxidant capacity evaluated by ORAC and DPPH assays or total phenol contents in any part of the plant, although in general the leaves of both plants showed the best antioxidant defense against the metal. In conclusion, Z. aethiopica and A. californica were able to cope to As through induction of a more sensitive enzymatic antioxidant response mechanism.

Carcinogénesis inducida por el virus del papiloma humano / Human papiloma virus-induced carcinogenesis

Introducción: la carcinogénesis es el proceso por el cual una célula normal setransforma en una célula cancerígena e involucra múltiples pasos, los cualesreflejan las alteraciones genéticas que conducen a la transformación progresiva del tejido normal hacia estados malignos. Los virus se han asociado con el desarrollo de cáncer, tanto en animales como en humanos, y dentro de estos se encuentra el Virus del Papiloma Humano (VPH), relacionado con el desarrollo del cáncercervical, considerado el segundo tipo de cáncer en mujeres a nivel mundial. Enesta revisión se describen los eventos responsables de la carcinogénesis inducida por el Virus del Papiloma Humano.Métodos: se realizó una búsqueda sistemática de la literatura en la base de datos Medline.Resultados: en esta revisión se discute la relación infección y cáncer, con énfasis en el proceso de carcinogénesis cervical inducido por el VPH y las moléculas involucradas en el mismo.Conclusiones: las oncoproteínas E6 y E7 son primordiales en el proceso detransformación maligna inducida por el VPH e involucran muchos otros factorescomo la interacción de dichas proteínas con factores reguladores del ciclocelular.

Alpha-lipoic acid regulates heme oxygenase gene expression and nuclear Nrf2 activation as a mechanism of protection against arsenic exposure in HepG2 cells.

Oxidative stress is a known mechanism induced, among other things, by arsenic toxicity. As a response, the cell triggers the synthesis of antioxidant and stress response elements like glutathione and heme oxygenase. Alpha-lipoic acid (ALA) is a well-known antioxidant that confers protection to oxidative stress conditions. We analyzed the effect of ALA pretreatment on Nrf2-responsive gene expression of HepG2 cells exposed to As(3+). Cells were treated with 5mM ALA and 8h later exposed to 50µM As(3+) for 24h, analyzing MTT-activity, glutathione content, Nrf2 induction and antioxidant gene expression. As(3+) increased glutathione (154%), heme oxygenase, glutamate cystein ligase, modifier subunit and metallothionein (35-fold, 10-fold and 9-fold, respectively). ALA prevented the strong expression of heme oxygenase by As(3+) exposure (from 35- to 5-times of control cells), which correlated with the reduction of Nrf2 observed in As(3+) group. ALA pretreatment can down-modulate the response mediated by Nrf2 and provide protection to As(3+) exposed HepG2 cells.

Expression profile of BRCA1 and BRCA2 genes in premenopausal Mexican women with breast cancer: clinical and immunohistochemical correlates.

Low BRCA1 gene expression is associated with increased invasiveness and influences the response of breast carcinoma (BC) to chemotherapeutics. However, expression of BRCA1 and BRCA2 genes has not been completely characterized in premenopausal BC. We analyzed the clinical and immunohistochemical correlates of BRCA1 and BRCA2 expression in young BC women. We studied 62 women (mean age 38.8 years) who developed BC before the age of 45 years. BRCA1 and BRCA2 mRNA expression was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR) and that of HER-2 and p53 proteins by immunohistochemistry. Body mass index (BMI) > or = 27 (52%) and a declared family history of BC (26%) were the main risk factors. Ductal infiltrative adenocarcinoma was found in 86% of the cases (tumor size >5 cm in 48%). Disease stages I-IV occurred in 2, 40, 55, and 3%, respectively (73% implicating lymph nodes). Women aged < or = 35 years (24%) had more family history of cervical cancer, stage III/IV disease, HER-2 positivity, and lower BRCA1 expression than older women (P < 0.05). BRCA1 and BRCA2 expression correlated in healthy, but not in tumor tissues (TT). Neither BRCA1 nor BRCA2 expression was associated with tumor histology, differentiation, nodal metastasis or p53 and HER-2 expression. After multivariate analysis, only disease stage explained BRCA1 mRNA levels in the lowest quartile. Premenopausal BC has aggressive clinical and molecular characteristics. Low BRCA1 mRNA expression is associated mainly with younger ages and advanced clinical stage of premenopausal BC. BRCA2 expression is not associated with disease severity in young BC women.

Current antioxidant molecular therapies for oxidative stress-related ailments.

Oxidative cell damage is a natural occurring phenomenon due to the aerobic conditions where cells are embedded; however, such injury can efficiently be controlled and repaired by the inherent antioxidants of the cell. When the oxidant/antioxidant balance is disrupted towards the former by any chemical, biological or physical insult a pathological state could be developed, therefore, an extensive list of compounds with proved or assumed antioxidants properties has largely been used for improving or restoring the health status. Pharmacological therapies as well as dietary or complementary therapies are continuously being investigated for the counteracting of the harmful or damaging effects of oxidation in cells or tissues. However, critical antioxidant levels are not always achieved at the target damaged cells by these approaches; on the other side, the expression of recombinant antioxidant genes specifically directed to the afflicted cell by gene delivery has shown remarkable results. In this review we summarize the literature focused on some of the current antioxidant molecular pharmacological strategies with particular emphasis to the gene transfer protocols involved in the treatment of oxidative stress-related disorders.

Treatment with human metalloproteinase-8 gene delivery ameliorates experimental rat liver cirrhosis.

BACKGROUND & AIMS: An extrahepatic human neutrophil collagenase complementary DNA (matrix metalloprotease-8) cloned in an adenovirus vector was used as a therapeutic agent in cirrhosis. METHODS: A high titer of clinical-grade AdMMP8 was obtained. RESULTS: HeLa cells transduced with AdMMP8 expressed recombinant matrix metalloprotease-8 messenger RNA and matrix metalloprotease-8 protein. Matrix metalloprotease-8 in culture sups showed enzymatic activity against native collagen type I, which was inhibited by ethylenediaminetetraacetic acid, 1,10-phenanthroline, and tissue inhibitor of metalloprotease-1. In vivo transduction showed matrix metalloprotease-8 activity, and studies to establish the efficacy of this characterized vector were performed in CCl(4) and bile duct-ligated cirrhotic rats. Transduction with 3 x 10(11) viral particles per kilogram resulted in hepatic detection of both messenger RNA and protein matrix metalloprotease-8. A consistent response in fibrosis reversal was observed in CCl(4) rats. Liver fibrosis in bile duct-ligated cirrhotic animals was decreased in 45%, along with diminished hydroxyproline content, after AdMMP8 treatment. The expression of matrix metalloprotease-2 and matrix metalloprotease-3 was up-regulated in AdMMP8 rats. Free tissue inhibitor of metalloprotease-1, as an indirect measurement of active uncomplexed matrix metalloproteases, was also increased in the AdMMP8 groups. Transforming growth factor-beta messenger RNA was diminished, and matrix metalloprotease-9 and hepatocyte growth factor increased. Treatment in both models correlated with improvements in ascites, functional hepatic tests, and gastric varices, indicating diminished intrahepatic blood pressure in animals injected with AdMMP8. CONCLUSIONS: Therefore, therapy with the matrix metalloprotease-8 gene is promising for use in a clinical setting.