16 research outputs found
Tipos morfológicos, número de parásitos por campo y carga parasitaria de Blastocystis sp proveniente de pacientes sintomáticos y asintomáticos:Tipos morfológicos de Blastocystis sp
Get PDFThe pathogenicity of Blastocystis sp is controversial, therefore, it is important to define diagnostic criteria for its determination. We evaluated the morphology of Blastocystis sp, number of parasites per field and per gram of faeces in patients with general symptoms and in healthy carriers. The study was a descriptive and non-experimental design. The microscopic observation and counting was done in ten consecutive fields in relation to 40X and stool weight in grams. We found 77% of samples positive for Blastocystis sp, 52% from patients with symptoms such as flatulence 6 (24%), abdominal pain 5 (20%), nausea 2 (8 %), diarrhea 6 (24%) and constipation 6 (24%) . The ranges of parasites per field more frequent in symptomatic patients were 0-3 (74%) and 7-10 (26%); and in the morphologies, the quantification of differential forms by field and the quantification of the number of parasites per field contributes to the technical optimization of routine coproparasitology asymptomatic group 100% of the patients were in the 0-3 range. In the 0-3 range asymptomatic patients had a lower number of parasites per gram of feces, while in the 7-10 range high parasite loads were observed only in symptomatic patients. Less granular forms in relation to vacuolar ones were found in both groups, in the 0-3 range of the symptomatic group, 85% vacuolar and 15% granular, and 76% vacuolar, and 24% granular in the asymptomatic. In conclusion, the study of the morphologies, the quantification of differential forms by field and the quantification of the number of parasites per field contributes to the technical optimization of routine coproparasitology
Bioenergetics adaptations and redox homeostasis in pregnancy and related disorders
Get PDFPregnancy is a challenging physiological process that involves maternal adaptations to the increasing energetics demands imposed by the growing conceptus. Failure to adapt to these requirements may result in serious health complications for the mother and the baby. The mitochondria are biosynthetic and energy-producing organelles supporting the augmented energetic demands of pregnancy. Evidence suggests that placental mitochondria display a dynamic phenotype through gestation. At early stages of pregnancy placental mitochondria are mainly responsible for the generation of metabolic intermediates and reactive oxygen species (ROS), while at later stages of gestation, the placental mitochondria exhibit high rates of oxygen consumption. This review describes the metabolic fingerprint of the placental mitochondria at different stages of pregnancy and summarises key signs of mitochondrial dysfunction in pathological pregnancy conditions, including preeclampsia, gestational diabetes and intrauterine growth restriction (IUGR). So far, the effects of placental-driven metabolic changes governing the metabolic adaptations occurring in different maternal tissues in both, healthy and pathological pregnancies, remain to be uncovered. Understanding the function and molecular aspects of the adaptations occurring in placental and maternal tissue’s mitochondria will unveil potential targets for further therapeutic exploration that could address pregnancy-related disorders. Targeting mitochondrial metabolism is an emerging approach for regulating mitochondrial bioenergetics. This review will also describe the potential therapeutic use of compounds with a recognised effect on mitochondria, for the management of preeclampsia
Neuroprotective effects of mitochondrial-targeted hydrogen sulphide donor, AP39 on H2O2-induced oxidative stress in human neuroblastoma SHSY5Y cell line
Get PDFOxidative stress (OS) resulting from imbalance in the generation of reactive oxygen species (ROS) and/or the dysfunction of the antioxidant machinery, is a key mechanism associated with the onset of neurodegenerative disorders. Although the molecular mechanisms are still elusive, the onset of disorders such as Alzheimer's and Parkinson's disease have been associated with mitochondrial dysfunction. Recently, a mitochondrial-targeted hydrogen sulphide (H2S) donor, AP39, has shown to promote cellular bioenergetics in OS related scenarios. The aim of this study was to explore the potential of AP39 to protect the mitochondrial function in an OS environment induced by hydrogen peroxide (H2O2). We assessed the potential effects of increasing concentrations of AP39 on cell viability, H2S availability and the mitochondrial bioenergetic response in resting (non-differentiated and differentiated) neuroblastoma SHSY5Y cell line. Further, we explored the role of AP39 in attenuating H2O2-induced mitochondrial dysfunction. Our results showed that nanomolar to micromolar concentrations of AP39 (0.1 μM – 3 μM) are not toxic to SHSY5Y cells, regardless of their differentiation status. Fluorescence detection of H2S observed AP39 co-localises within the mitochondria in a concentration dependent manner. Whilst a lower concentration of AP39 (0.3 μM) was required to improve the mitochondrial bioenergetics in resting non-differentiated cells, 1 μM produced this effect in their differentiated counterparts. In both, non-differentiated and differentiated cells, AP39 reduced H2O2-induced mitochondrial impairments by improving the parameters of the mitochondrial function and abrogating the generation of mitochondrial ROS. These suggest that mitochondrial targeted delivery of H2S may attenuate neuronal toxicity in neuronal disorders associated with OS-induced mitochondrial dysfunction
Partial Mitigation of Oxidized Phospholipid-Mediated Mitochondrial Dysfunction in Neuronal Cells by Oxocarotenoids
Get PDFMitochondria are important (patho)physiological sources of reactive oxygen species (ROS) that mediate mitochondrial dysfunction and phospholipid oxidation; an increase in mitochondrial content of oxidized phospholipid (OxPL) associates with cell death. Previously we showed that the circulating OxPL 1-palmitoyl-2-(5’-oxo-valeroyl)-sn-glycero-3-phosphocholine (POVPC) increases in patients with Alzheimer’s disease (AD), and associates with lower plasma antioxidant oxocarotenoids, zeaxanthin, and lutein. Since oxocarotenoids are metabolized in mitochondria, we propose that during AD, lower concentrations of mitochondrial zeaxanthin and lutein may result in greater phospholipid oxidation and predispose to neurodegeneration. Here, we have investigated whether non-toxic POVPC concentrations impair mitochondrial metabolism in differentiated (d)SH-SY5Y neuronal cells and whether there is any protective role for oxocarotenoids against mitochondrial dysfunction. After 24 hours, glutathione (GSH) concentration was lower in neuronal cells exposed to POVPC (1–20μM) compared with vehicle control without loss of viability compared to control. However, mitochondrial ROS production (determined by MitoSOX oxidation) was increased by 50% only after 20μM POVPC. Following delivery of lutein (0.1-1μM) and zeaxanthin (0.5-5μM) over 24 hours in vitro, oxocarotenoid recovery from dSH-SY5Y cells was >  50%. Co-incubation with oxocarotenoids prevented loss of GSH after 1μM but not 20μM POVPC, whereas the increase in ROS production induced by 20μM POVPC was prevented by lutein and zeaxanthin. Mitochondrial uncoupling increases and ATP production is inhibited by 20μM but not 1μM POVPC; carotenoids protected against uncoupling although did not restore ATP production. In summary, 20μM POVPC induced loss of GSH and a mitochondrial bioenergetic deficit in neuronal cells that was not mitigated by oxocarotenoids
MZe786 Rescues Cardiac Mitochondrial Activity in High sFlt-1 and Low HO-1 Environment
Get PDFHypertensive disorder in pregnancy is a major cause of maternal and perinatal mortality worldwide. Women who have had preeclampsia are at three to four times higher risk in later life of developing high blood pressure and heart disease. Soluble Flt-1 (sFlt-1) is elevated in preeclampsia and may remain high postpartum in women with a history of preeclampsia. Heme oxygenase-1 (Hmox1/HO-1) exerts protective effects against oxidative stimuli and is compromised in the placenta of pregnant women with preeclampsia. We hypothesized that sFlt-1 inhibits cardiac mitochondrial activity in HO-1 deficient mice. HO-1 haplo-insufficient mice (Hmox1+/−) were injected with adenovirus encoding sFlt-1 (Ad-sFlt-1) or control virus (Ad-CMV). Subsequently, they were treated daily with either placebo or MZe786 for six days, when the heart tissue was harvested to assess cardiac mitochondrial activity. Here, we show that the loss of HO-1 disturbed cardiac mitochondrial respiration and reduced mitochondrial biogenesis. The overexpression of sFlt-1 resulted in the inhibition of the cardiac mitochondrial activity in Hmox1+/− mice. The present study demonstrates that the hydrogen sulfide (H2S) releasing molecule, MZe786, rescues mitochondrial activity by stimulating cardiac mitochondrial biogenesis and antioxidant defense in Hmox1−/− mice and in Hmox1+/− mice exposed to a high sFlt-1 environment
Medida del colesterol de lipoproteÃnas de baja densidad utilizando tres metodologÃas:Medición de colesterol de lipoproteÃnas de baja densidad
Get PDFConsidering that there is still no standard methodology for routine determination of low density lipoprotein (LDL-c) it was decided to evaluate their analytical determination using three techniques: homogeneous enzymatic determination, polyvinyl sulphate precipitation and Friedewald formula. Ninety-eight serum samples were processed; triglycerides (TG), total cholesterol (TC), high-density lipoprotein (HDL-c) and LDL-c were determined. Mean total cholesterol was 194.46 ± 43.54 mg/dL, HDL-C was 51.12 ± 12.36 mg/dL and TG was 132.88 ± 76.93 mg/dL. Although regression analysis showed a good correlation between LDL-c, the results showed a statistically significative difference in them when TG levels exceeded 200 mg/dL. It was mainly observed in the precipitation method and the Friedewald formula, the latter values being significantly lower (LDL-C by precipitation: 141.3 ± 26.2 mg/dL, LDL-C by the Friedewald formula: 110, 1 ± 35.4 mg/dL). Moreover, this difference affected the proportion of individuals classified according to their coronary risk. It is necessary to compare the techniques applied in this study with beta quantification to assess which has a higher level of accuracy
Efecto del tratamiento con praziquantel sobre la actividad de la fosfatasa alcalina, fosfatasa acida, superoxido dismutasa en extractos crudos y productos de excreción-secreción de gusanos de Schistosoma mansoni:Praziquantel y enzimas de Schistosoma mansoni
Get PDFVenezuela is among South American countries affected by schistosomiasis and chemotherapy with praziquantel (PZQ) is the main control strategy. We determined the quantitative effect of treatment with PZQ on alkaline phosphatase activity (ALP), acid phosphatase (ACP) and superoxide dismutase (SOD) in soluble antigens of worms (SWAP) and excretion-secretion products (EEP) of male and female worms (SMWAPc, SFWAPc, ESPWMc and ESPWHc) or incubated with PZQ in vitro (SMWAPPZQ, SFWAPPZQ, ESPWMPZQ and ESPWHPZQ). Total proteins were determined by colorimetry, SOD and ACP by spectrophotometry and fluorometry ALP. There was higher protein concentration in the untreated worms EG, and the preparations obtained after incubation with PZQ in vitro, in the EG, an increase in ACP activity in the EG and PG prepared with non-treated worms and a decrease of such activity on the EG and treated PG. On the other hand, SOD activity, the EG showed statistical significance in the treated worms. In the PG showed the same behavior, but those differences were not statistically significant. Similarly, there was a decrease in the concentration of ALP noticeable in the EG and worm PGh treated worms relative to untreated statistically significant. In conclusion, we observed a decrease in total protein, ACP and SOD enzyme activities and concentration of ALP, and EG in PG treated worms
MZe786, a hydrogen sulfide-releasing aspirin prevents preeclampsia in heme oxygenase-1 haplodeficient pregnancy under high soluble flt-1 environment
Get PDFPreeclampsia affects one in twelve of the 130 million pregnancies a year. The lack of an effective therapeutic to prevent or treat it is responsible for an annual global cost burden of 100 billion US dollars. Preeclampsia also affects these women later in life as it is a recognised risk factor for cardiovascular disease, stroke and vascular dementia. Our laboratory demonstrated that preeclampsia is associated with high soluble fms-like tyrosine kinase 1 (sFlt-1) and low heme oxygenase-1 (HO1/Hmox1) expression. Here we sought to determine the therapeutic value of a novel H 2S-releasing aspirin (MZe786) in HO-1 haploid deficient (Hmox1 +/−) pregnant mice in a high sFlt-1 environment. Pregnant Hmox1 +/− mice were injected with adenovirus encoding sFlt-1 or control virus at gestation day E11.5. Subsequently, Hmox1 +/− dams were treated daily with a number of treatment regimens until E17.5, when maternal and fetal outcomes were assessed. Here we show that HO-1 compromised mice in a high sFlt-1 environment during pregnancy exhibit severe preeclampsia signs and a reduction in antioxidant genes. MZe786 ameliorates preeclampsia by reducing hypertension and renal damage possibly by stimulating antioxidant genes. MZe786 also improved fetal outcome in comparison with aspirin alone and appears to be a better therapeutic agent at preventing preeclampsia than aspirin alone
Exploring mitochondrial hydrogen sulfide signalling for therapeutic interventions in vascular diseases
Get PDFHydrogen sulfide (H2S), a gaseous signalling molecule, is important in numerous physiological and pathophysiological processes. Despite its initial identification as an environmental toxin, H2S is now well described as an essential physiological molecule that is finely balanced to maintain cellular functions, especially in modulating mitochondrial activity. Mitochondria are responsible for the oxidation of H2S and its safe elimination while maintaining mitochondrial biogenesis. H2S oxidation in mitochondria generates various reactive sulfur species that could post-translationally modify proteins by sulfhydration. Sulfhydrated proteins participate in many regulatory activities either by direct interactions in the electron transport chain or indirect regulation by epigenetics. These investigations explain the importance of research of H2S as a therapeutic molecule beyond the traditional understanding as a protective role through its anti-inflammatory and antioxidant properties. This review focuses on highlighting the significant involvement of the H2S pathway in vascular diseases and current H2S donors for therapeutic use under development
Sodium Thiosulphate-Loaded Liposomes Control Hydrogen Sulphide Release and Retain Its Biological Properties in Hypoxia-like Environment
Get PDFHypoxia, or insufficient oxygen availability is a common feature in the development of a myriad of cardiovascular-related conditions including ischemic disease. Hydrogen sulphide (H2S) donors, such as sodium thiosulphate (STS), are known for their cardioprotective properties. However, H2S due to its gaseous nature, is released and cleared rapidly, limiting its potential translation to clinical settings. For the first time, we developed and characterised liposome formulations encapsulating STS and explored their potential for modulating STS uptake, H2S release and the ability to retain pro-angiogenic and biological signals in a hypoxia-like environment mirroring oxygen insufficiency in vitro. Liposomes were prepared by varying lipid ratios and characterised for size, polydispersity and charge. STS liposomal encapsulation was confirmed by HPLC-UV detection and STS uptake and H2S release was assessed in vitro. To mimic hypoxia, cobalt chloride (CoCl2) was administered in conjunction with formulated and non-formulated STS, to explore pro-angiogenic and metabolic signals. Optimised liposomal formulation observed a liposome diameter of 146.42 ± 7.34 nm, a polydispersity of 0.22 ± 0.19, and charge of 3.02 ± 1.44 mV, resulting in 25% STS encapsulation. Maximum STS uptake (76.96 ± 3.08%) from liposome encapsulated STS was determined at 24 h. Co-exposure with CoCl2 and liposome encapsulated STS resulted in increased vascular endothelial growth factor mRNA as well as protein expression, enhanced wound closure and increased capillary-like formation. Finally, liposomal STS reversed metabolic switch induced by hypoxia by enhancing mitochondrial bioenergetics. These novel findings provide evidence of a feasible controlled-delivery system for STS, thus H2S, using liposome-based nanoparticles. Likewise, data suggests that in scenarios of hypoxia, liposomal STS is a good therapeutic candidate to sustain pro-angiogenic signals and retain metabolic functions that might be impaired by limited oxygen and nutrient availability
