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1.
Respir Med ; 227: 107658, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38704051

RESUMEN

Pulmonary hypertension (PH) in chronic obstructive pulmonary disease (COPD) is associated with worse clinical outcomes and decreased survival rates. In absence of disease specific diagnostic/therapeutic targets and unclear pathophysiology, there is an urgent need for the identification of potential genetic/molecular markers and disease associated pathways. The present study aims to use a bioinformatics approach to identify and validate hypoxia-associated gene signatures in COPD-PH patients. Additionally, hypoxia-related inflammatory profile is also explored in these patients. Microarray dataset obtained from the Gene Expression Omnibus repository was used to identify differentially expressed genes (DEGs) in a hypoxic PH mice model. The top three hub genes identified were further validated in COPD-PH patients, with chemokine (C-X-C motif) ligand 9 (CXCL9) and CXCL12 showing significant changes in comparison to healthy controls. Furthermore, multiplexed analysis of 10 inflammatory cytokines, tumor necrosis factor alpha (TNF-α), transforming growth factor ß (TGF-ß), interleukin 1-beta (IL-1ß), IL-4, IL-5, IL-6, IL-13, IL-17, IL-18 and IL-21 was also performed. These markers showed significant changes in COPD-PH patients as compared to controls. They also exhibited the ability to differentially diagnose COPD-PH patients in comparison to COPD. Additionally, IL-6 and IL-17 showed significant positive correlation with systolic pulmonary artery pressure (sPAP). This study is the first report to assess the levels of CXCL9 and CXCL12 in COPD-PH patients and also explores their link with the inflammatory profile of these patients. Our findings could be extended to better understand the underlying disease mechanism and possibly used for tailoring therapies exclusive for the disease.

2.
Blood Cells Mol Dis ; 105: 102821, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38218172

RESUMEN

Dyslipidemia is frequently observed in polycystic ovarian syndrome (PCOS). Changes in plasma lipid levels potentially alter erythrocyte membrane lipid composition due to lack of inbuilt lipid synthesis machinery. Therefore, development of morphologically altered erythrocytes in PCOS patients with dyslipidemia is expected. However, this has not been established so far. So, we took this opportunity to explore the morphological alterations among dyslipidemic PCO women. We recruited thirty-five dyslipidemic PCOS women (satisfying Rotterdam criteria, without medication) and twenty-five age-matched healthy controls. Scanning electron microscopy revealed a significant increase in the number of stomatocytes, acanthocytes, and echinocytes in the PCO group. PCO group showed a considerable decrease in plasma antioxidant levels. Elevated lipid peroxidation, protein carbonylation, and decreased free thiol group in erythrocyte membrane in PCOS suggest oxidative degradation of the erythrocyte membrane. Elevated intracellular ROS levels, increased methemoglobin formation, and a decrease in NADPH methemoglobin reductase in PCOS also indicate altered physicochemical property of hemoglobin due to oxidative overload. Additionally, these patients exhibit a rise in erythrocyte membrane cholesterol and triglyceride, which promotes the membrane to become less fluidic and less fragile. Thus, these results corroborate a potential role in altering erythrocyte morphology among dyslipidemic PCO women.


Asunto(s)
Dislipidemias , Síndrome del Ovario Poliquístico , Humanos , Femenino , Triglicéridos , Antioxidantes , Eritrocitos , Dislipidemias/complicaciones
3.
J Phys Chem A ; 127(25): 5360-5373, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37331016

RESUMEN

Chemical substituents can influence photodynamics by altering the location of critical points and the topography of the potential energy surfaces (electronic effect) and by selectively modifying the inertia of specific nuclear modes (inertial effects). Using nonadiabatic dynamics simulations, we investigate the impact of methylation on S2(ππ*) internal conversion in acrolein, the simplest linear α,ß-unsaturated carbonyl. Consistent with time constants reported in a previous time-resolved photoelectron spectroscopy study, S2 → S1 deactivation occurs on an ultrafast time scale (∼50 fs). However, our simulations do not corroborate the sequential decay model used to fit the experiment. Instead, upon reaching the S1 state, the wavepacket bifurcates: a portion undergoes ballistic S1 → S0 deactivation (∼90 fs) mediated by fast bond-length alternation motion, while the remaining decays on the picosecond time scale. Our analysis reveals that methyl substitution, generally assumed to mainly exert inertial influence, is also manifested in important electronic effects due to its weak electron-donating ability. While methylation at the ß C atom gives rise to effects principally of an inertial nature, such as retarding the twisting motion of the terminal -CHCH3 group and increasing its coupling with pyramidalization, methylation at the α or carbonyl C atom modifies the potential energy surfaces in a way that also contributes to altering the late S1-decay behavior. Specifically, our results suggest that the observed slowing of the picosecond component upon α-methylation is a consequence of a tighter surface and reduced amplitude along the central pyramidalization, effectively restricting the access to the S1/S0-intersection seam. Our work offers new insight into the S2(ππ*) internal conversion mechanisms in acrolein and its methylated derivatives and highlights site-selective methylation as a tuning knob to manipulate photochemical reactions.

4.
Metabolomics ; 19(5): 50, 2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-37154845

RESUMEN

INTRODUCTION: Gestational hypertension (GH) is defined as the presence of systolic blood pressure (BP) ≥ 140 mm Hg and/or diastolic BP ≥ 90 mm Hg, measured at least 4 h apart after 20 weeks of gestation. Early identification of women at high-risk of developing GH could contribute significantly towards improved maternal and fetal outcomes. OBJECTIVES: To determine early metabolic biomarkers in women with GH as compared with normotensive women. METHODS: Serum samples were collected from subjects during three stages of their pregnancy: 8-12 weeks, 18-20 weeks and after 28 weeks (< 36 weeks) of gestation and studied using nuclear magnetic resonance (NMR) metabolomics approach. Multivariate and univariate analyses were performed to determine the significantly altered metabolites in GH women. RESULTS: A total of 10 metabolites, including isoleucine, glutamine, lysine, proline, histidine, phenylalanine, alanine, carnitine, N-acetyl glycoprotein and lactic acid were observed to be significantly downregulated during all pregnancy stages in women with GH as compared with controls. Furthermore, expression of 5 metabolites in the first trimester i.e., phenylalanine [area under the curve (AUC) = 0.745], histidine [AUC = 0.729], proline [AUC = 0.722], lactic acid [AUC = 0.722], and carnitine [AUC = 0.714] exhibited highest potential in discriminating GH from normotensive women. CONCLUSION: The present study is the first of its kind to identify significantly altered metabolites that have the potential to discriminate between women at risk of developing GH and normotensive women across three trimesters of pregnancy. This opens up the possibility of exploring these metabolites as potential early predictive markers of GH.


Asunto(s)
Hipertensión Inducida en el Embarazo , Preeclampsia , Embarazo , Humanos , Femenino , Hipertensión Inducida en el Embarazo/diagnóstico , Histidina , Metabolómica , Fenilalanina
5.
Reprod Sci ; 30(4): 1207-1216, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35802293

RESUMEN

Polycystic ovary syndrome (PCOS) is a heterogeneous entity comprising broad spectra of ovarian disorders with trademark features of metabolic syndrome like insulin resistance, obesity, and dyslipidaemia to name a few. Hyperhomocysteinemia, an independent risk factor of metabolic syndrome, has been suggested as a causative factor in spontaneous miscarriage in PCOS. However, it is yet to be resolved whether hyperhomocysteinemia has a contributory role in the pathogenesis or could direct long-term sequences of the syndrome. A total of 2355 women with history of one or more first trimester abortions were screened and 1539 were selected for the study. Selected patients were initially divided by the presence or absence of PCOS, while subsequent stratification was based on hyperhomocysteinemia, insulin resistance, and/or obesity. The miscarriage population/s was mostly represented by hyperhomocysteinemia in both the cohorts (PCOS: 69.08% vs. non-PCOS: 56.68%). ROC-AUC values suggest increased predisposition of hyperhomocysteinemia-mediated miscarriage (hyperhomocysteinemia: 0.778; insulin resistance: 0.601; BMI: 0.548). A probabilistic causal model was designed using dynamic Bayesian network to evaluate the time-series data points before, during, and after pregnancy which revealed a possibility of 32.24% (n = 79) of PCOS cohort developing hypertension, 26.94% (n = 66) of onset of diabetes and 4.49% cardiovascular disease 3 years following pregnancy. We conclude hyperhomocysteinemia may possibly contribute to spontaneous miscarriage and related to metabolic derailments later in life.


Asunto(s)
Aborto Espontáneo , Hiperhomocisteinemia , Resistencia a la Insulina , Síndrome Metabólico , Síndrome del Ovario Poliquístico , Embarazo , Humanos , Femenino , Síndrome del Ovario Poliquístico/complicaciones , Aborto Espontáneo/etiología , Síndrome Metabólico/complicaciones , Hiperhomocisteinemia/complicaciones , Teorema de Bayes , Obesidad/complicaciones , Modelos Estadísticos
6.
Cell Signal ; 101: 110486, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36208704

RESUMEN

Melanoma is one of the most consequential skin cancer with a rising death incidences. Silent but belligerent nature of metastatic sprouting is the leading cause of melanoma related mortality. Invasion of metastatic cells and re-expression of E-Cadherin play the crucial role in the establishment of secondary tumor at distal sites. Thus, manipulation of tumor cell invasion in parallel to regulation of E-Cadherin expression can be considered as potential anti-metastatic strategy. Evidences suggested key role of reactive oxygen species associated ROCK activities in the modulation of metastatic invasion via F-actin stabilization. Here, we first-time report Decylubiquinone, a dietary Coenzyme Q10 analog, as an effective attenuator of pulmonary metastatic melanoma in C57BL/6 mice. Current study depicted detailed molecular interplay associated with Decylubiquinone mediated phosphorylation of ROCKII at Tyr722 along with reduced phosphorylation of ROCKII Ser1366 leading to suppression of Limk1/2-Cofilin-F-actin stabilization axis that finally restricted B16F10 melanoma cell invasion at metastatic site. Analysis further deciphered the role of HNF4α as its nuclear translocation modulated E-Cadherin expression, the effect of reactive oxygen species dependent ROCKII activity in secondarily colonized B16F10 melanoma cells at lungs. Thus unbosoming of related signal orchestra represented Decylubiquinone as a potential remedial agent against secondary lung melanoma.


Asunto(s)
Neoplasias Pulmonares , Melanoma Experimental , Melanoma , Ratones , Animales , Actinas , Especies Reactivas de Oxígeno , Línea Celular Tumoral , Ratones Endogámicos C57BL , Cadherinas/metabolismo , Melanoma/metabolismo , Pulmón/metabolismo , Neoplasias Pulmonares/metabolismo , Metástasis de la Neoplasia/patología , Melanoma Experimental/patología , Movimiento Celular
7.
J Phys Chem A ; 126(36): 6021-6031, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36069531

RESUMEN

Nonadiabatic excited state dynamics are important in a variety of processes. Theoretical and experimental developments have allowed for a great progress in this area, while combining the two is often necessary and the best approach to obtain insight into the photophysical behavior of molecules. In this Feature Article we use examples of our recent work combining time-resolved photoelectron spectroscopy with theoretical nonadiabatic dynamics to highlight important lessons we learned. We compare the nonadiabatic excited state dynamics of three different organic molecules with the aim of elucidating connections between structure and dynamics. Calculations and measurements are compared for uracil, 1,3-cyclooctadiene, and 1,3-cyclohexadiene. The comparison highlights the role of rigidity in influencing the dynamics and the difficulty of capturing the dynamics accurately with calculations.


Asunto(s)
Teoría Cuántica , Uracilo , Espectroscopía de Fotoelectrones , Uracilo/química
8.
Cell Signal ; 97: 110389, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35718242

RESUMEN

Rho-associated coiled-coil kinase (ROCK) inhibition decreases tumourogenic growth, proliferation and angiogenesis. Multifaceted evidences are there about the role of ROCK in cancer progression, but isoform specific analysis in secondary pulmonary melanoma is still unaddressed. This study explored the operating function of ROCK in the metastasis of B16F10 mice melanoma cell line. Inhibition by KD-025 indicated dual wielding role of ROCKII as it is associated with the regulation of MMP9 activity responsible for extra-cellular matrix (ECM) degradation as well as angiogenic invasion as an effect of Src-FAK-STAT3 interaction dependent VEGF switching. We found the assisting role of ROCKII, not ROCKI in nuclear localization of Smads that effectively increased MMP9 expression and activity (p < 0.01). This cleaved the protein components of ECM thereby played a crucial role in tissue remodeling at secondary site during establishment of metastatic tumour. ROCKII phosphorylation at Ser1366 as an activation of the same was imprinted essential for oncogenic molecular bagatelle leading to histo-architectural change of pulmonary tissue with extracellular matrix degradation as a consequence of invasion. Direct correlation of pROCKIISer1366 with MMP9 as well as VEGF expression in vivo studies cue to demonstrate the importance of pROCKIISer1366 inhibition in the context of angiogenesis, and metastasis suggesting ROCKII signaling as a possible target for the treatment of secondary lung cancer specially in metastatic melanoma.


Asunto(s)
Neoplasias Pulmonares , Melanoma , Quinasas Asociadas a rho , Animales , Movimiento Celular/fisiología , Neoplasias Pulmonares/secundario , Metaloproteinasa 9 de la Matriz , Melanoma/patología , Ratones , Neovascularización Patológica , Proteínas Smad , Factor A de Crecimiento Endotelial Vascular , Quinasas Asociadas a rho/metabolismo
9.
Biosens Bioelectron ; 211: 114332, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35594627

RESUMEN

The present study employs density functional theory-based first principle calculation to investigate the electron transport properties of polyaniline following exposure to acidic and alkaline pH. In-situ deposited polyaniline-based paper device maintains emeraldine salt form while it is exposed to acidic pH and converts to emeraldine base when it is subjected to alkaline pH solutions. These structural changes at acidic and alkaline pH are validated experimentally by Raman spectra. Furthermore, the Raman spectra computed from density functional theory are validated with the experimental spectra. The changes in the theoretical energy band gap of polyaniline obtained from first principle calculations were correlated with the changes in the experimental impedimetric response of the sensor after exposure to acidic and alkaline solutions. Finally, the impedimetric responses were used to predict urine pH through a machine learning based smart and interactive web application. Different machine learning based regression models were implemented to acquire the best possible outcome. Gradient Boosting Regressor with least square loss model was selected as it showed lowest mean square, mean absolute, and root mean square error than other models. The smart sensing platform successfully predicts the unknown pH of urine samples with an average accuracy of more than 98%. The locally deployed smart web app can be accessed within a local area network by the end-user, which holds promise towards effective detection of urinary pH.


Asunto(s)
Técnicas Biosensibles , Aplicaciones Móviles , Compuestos de Anilina , Concentración de Iones de Hidrógeno , Aprendizaje Automático
10.
J Phys Chem Lett ; 12(21): 5099-5104, 2021 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-34028278

RESUMEN

We compare different levels of theory for simulating excited state molecular dynamics and use time-resolved photoelectron spectroscopy measurements to benchmark the theory. We perform trajectory surface hopping simulations for uracil excited to the first bright state (ππ*) using three different levels of theory (CASSCF, MRCIS, and XMS-CASPT2) in order to understand the role of dynamical correlation in determining the excited state dynamics, with a focus on the coupling between different electronic states and internal conversion back to the ground state. These dynamics calculations are used to simulate the time-resolved photoelectron spectra. The comparison of the calculated and measured spectra allows us to draw conclusions regarding the relative insights and quantitative accuracy of the calculations at the three different levels of theory, demonstrating that detailed quantitative comparisons of time-resolved photoelectron spectra can be used to benchmark methodology.

11.
Faraday Discuss ; 228(0): 266-285, 2021 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-33566040

RESUMEN

The photophysics and photochemistry of DNA/RNA nucleobases have been extensively investigated during the past two decades, both experimentally and theoretically. The ultrafast relaxation of the canonical nucleobases following photoexcitation is of significant interest when it comes to understanding how nature has ensured their photostability. Here we study the excited state dynamics of uracil which is a nucleobase found in RNA. Although theory and experiment have shed significant light on understanding the photoexcited dynamics of uracil, there are still disagreements in the literature about specific details. In order to examine how the dynamics is influenced by the underlying electronic structure theory, we have performed non-adiabatic excited state dynamics simulations of uracil using on-the-fly trajectory surface hopping methodology on potential energy surfaces calculated at different electronic structure theory levels (CASSCF, MRCIS, XMS-CASPT2, TD-DFT). These simulations reveal that the dynamics are very sensitive to the underlying electronic structure theory, with the multi-reference theory levels that include dynamic correlation, predicting that there is no trapping on the absorbing S2 state, in contrast to predictions from lower level electronic structure results. The dynamics are instead governed by ultrafast decay to the ground state, or trapping on the dark S1 state.


Asunto(s)
ARN , Uracilo , ADN
12.
J Chem Phys ; 153(7): 074301, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32828099

RESUMEN

We present UV pump, vacuum ultraviolet probe time-resolved photoelectron spectroscopy measurements of the excited state dynamics of cis,cis-1,3-cyclooctadiene. A 4.75 eV deep UV pump pulse launches a vibrational wave packet on the first electronically excited state, and the ensuing dynamics are probed via ionization using a 7.92 eV probe pulse. The experimental results indicate that the wave packet undergoes rapid internal conversion to the ground state in under 100 fs. Comparing the measurements with electronic structure and trajectory surface hopping calculations, we are able to interpret the features in the measured photoelectron spectra in terms of ionization to several states of the molecular cation.

13.
J Chem Phys ; 152(17): 174302, 2020 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-32384830

RESUMEN

We have performed trajectory surface hopping dynamics for cis,cis-1,3-cyclooctadiene to investigate the photochemical pathways involved after being excited to the S1 state. Our calculations reveal ultrafast decay to the ground state, facilitated by conical intersections involving distortions around the double bonds. The main distortions are localized on one double bond, involving twisting and pyramidalization of one of the carbons of that double bond (similar to ethylene), while a limited number of trajectories decay via delocalized (non-local) twisting of both double bonds. The interplay between local and non-local distortions is important in our understanding of photoisomerization in conjugated systems. The calculations show that a broad range of the conical intersection seam space is accessed during the non-adiabatic events. Several products formed on the ground state have also been observed.

14.
Artículo en Inglés | MEDLINE | ID: mdl-31114548

RESUMEN

Benzo(a)pyrene [B(a)P] is the toxic environmental Polycyclic Aromatic Hydrocarbon (PAH), that exerts male reproductive dysfunctions. In this study the molecular mechanism of B(a)P induced Leydig cell steroidogenic dysfunctions and its protective mechanism of action with a natural Aryl hydrocarbon receptor (AhR) antagonist and anti-oxidant, Resveratrol (Res) has been investigated. B(a)P exposure induced ROS mediated steroidogenic imbalance via activation of p38MAPK and repression of testosterone level as well as other steroidogenic enzymes like CYPIIA1, 3ß-HSD, 17ß-HSD expressions. B(a)P exposure decreased StAR protein expression along with increased DAX-1, a transcriptional repressor of StAR gene. Along with that B(a)P decreased the expression of SF-1 that acts as a transcriptional inducer of StAR gene expression. The study has established Resveratrol as a potential agent combating the deleterious effect of B(a)P on Leydig cell steroidogenesis. Resveratrol treatment resulted significant protection against B(a)P by scavenging ROS and modulating the transcriptional regulation of anti-oxidant enzymes. Furthermore, Resveratrol also prevented stress kinase like p38 MAPK activation and increased StAR protein expression through the reduction of DAX-1 expression. Moreover, the testosterone production was efficiently restored with Resveratrol treatment. ChIP assay also revealed that resveratrol improved SF-1expression which further increased the StAR gene expression. Resveratrol acted efficiently against B(a)P, through its anti-oxidative properties as well as inhibits p38MAPK and increased steroidogenesis and StAR expression through the modulation of SF-1 gene expression.

15.
Environ Toxicol Pharmacol ; 68: 120-132, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30889542

RESUMEN

Andrographolide regimen in single or in combination with anticancer drugs is a promising new strategy to reverse chemoresistance in heaptocellular carcinoma. Apoptosis inducing factor (AIF) may regulate a complementary, cooperative or redundant pathway, along with caspase cascades. Despite these findings, mechanisms underlying caspase-dependent and-independent signaling pathways in andrographolide -induced apoptosis in cisplatin-resistant human hepatocellular carcinoma cell line (HepG2CR) remain unclear. Andrographolide treatment effectively reduced NF-κß nuclear localization by modulating protein kinase A- protein phosphatase 2 A- Iκß kinase (PKA/PP2 A/IKK) axis that in turn maintains initiator caspase8 activity. Lysosomal distribution of tBid stimulates cytosolic cathepsin B resulting accumulation of truncated-AIF with induction in scramblase mediated phosphatidylserine exposure in HepG2CR cells. Andrographolide treatment thereby switch on subG1 phase arrest by modulating cellular check points (cyclin A, B, cyclin dependent kinase-1) cueing to the apoptosis event. Collectively, this study suggested antineoplastic potential of andrographolide through PKA/PP2 A/IKK pathway in HepG2CR cells.


Asunto(s)
Antineoplásicos/farmacología , Catepsina B/metabolismo , Cisplatino/farmacología , Diterpenos/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Proteínas de Transferencia de Fosfolípidos/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo
16.
Biochem Biophys Res Commun ; 503(1): 8-13, 2018 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-29660344

RESUMEN

Women with polycystic ovary syndrome (PCOS) are at increased risk of cardiovascular diseases (CVD); however, the independent role of PCOS in the incident CVD remains unknown. There are reports that hyperhomocysteinemia (HHcy), a potential cause of CVD, is frequently associated with PCOS. The present study investigates the independent attributes of hyperandrogenemia (HA), the integral associate of PCOS, and HHcy in causing atherogenic dyslipidemia. Twenty-five-day old rats were treated with homocysteine (Hcy) at 50 mg/kg/day dose level for 12 weeks. The HepG2 cell lines transfected with siRNA directed to PCSK9 were challenged with Hcy, homocysteine thiolactone (HTL), testosterone, 5α-dihydroxytestosterone (5α-DHT), or estradiol for 24 h. Rats administered with Hcy developed HHcy and displayed PCOS-like phenotypes with adversely altered lipid homeostasis and attenuated PI3K-AKT and Wnt signalling cascade. Overexpression of steroidogenic acute regulatory protein (StAR) and down-regulated expression of Aromatase together with elevated testosterone level marked the state of HA. In culture, the HepG2 cells responded independently to Hcy, HTL, testosterone, and 5α-DHT by an overt expression of PCSK9 and down-regulated expression of LDLR. The effect was magnified under the combined influence of Hcy and androgen(s). Estradiol, by contrast, exhibited the reverse effect. The findings suggest that HA may independently attribute to an increased cardiovascular risk in PCOS; however, the coexistence of HHcy catalyzes the risk further.


Asunto(s)
Andrógenos/sangre , Hiperhomocisteinemia/complicaciones , Hiperhomocisteinemia/metabolismo , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/metabolismo , Proproteína Convertasa 9/metabolismo , Receptores de LDL/metabolismo , Animales , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/metabolismo , Modelos Animales de Enfermedad , Dislipidemias/etiología , Dislipidemias/metabolismo , Femenino , Expresión Génica , Células Hep G2 , Humanos , Metabolismo de los Lípidos , Redes y Vías Metabólicas , Inhibidores de PCSK9 , Síndrome del Ovario Poliquístico/genética , Proproteína Convertasa 9/genética , ARN Interferente Pequeño/genética , Ratas , Ratas Sprague-Dawley , Receptores de LDL/genética , Factores de Riesgo
17.
Faraday Discuss ; 207(0): 329-350, 2018 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-29364301

RESUMEN

DNA/RNA photohydrates represent a class of well-known biomolecular lesions formed by the absorption of near- to mid-UV light. They are formed via a photoinduced nucleophilic hydrolysis reaction in which water is split (via nucleobase sensitisation) into H + OH radicals. These nascent radicals can then add across C5[double bond, length as m-dash]C6, saturating the preexisting double bond. If unrepaired, such lesions can lead to mutagenic carcinogenesis, which is responsible for several forms of cancer. Using high-level electronic structure theory (CASPT2), we map the key excited-state reaction paths associated with the reactivity of DNA (guanine and thymine) and RNA (uracil) nucleobases with water. At the outset, we consider the intrinsic reactivity in the isolated gas phase - in which the water (cluster) + chromophore complex is free from environmental perturbations. We then extrapolate the thymine nucleobase to the bulk DNA environment in aqueous solution in order to ascertain the relative importance of hydrate formation in a more complex biological environment. In this latter study we use high-level mixed quantum/classical (QM/MM: CASPT2/AMBER) methods.


Asunto(s)
ADN/química , ARN/química , Gases/química , Estructura Molecular , Procesos Fotoquímicos , Teoría Cuántica , Soluciones , Rayos Ultravioleta
18.
Exp Clin Endocrinol Diabetes ; 125(7): 441-448, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28407664

RESUMEN

Fenugreek (Trigonella foenum graecum), a medicinal herb with potent antihyperglycaemic and hypoglycaemic effects, is used to treat diabetes. This study is aimed to explore the interaction of fenugreek seed extract (FSE) and HPT (hypothalamic-pituitary-thyroid) axis in context of leptin secretion which have important role in normal and type-1 diabetic subjects. FSE (confirmed to contain trigonelline, diosgenin, 4 hydroxyisoleucine) was gavaged (0.25 gm/kg body weight/day) to normal and alloxan-induced type-1 diabetic rats for 4 weeks. Expression of hypothalamic prepro-TRH (Thyrotropin releasing hormone) mRNA, serum levels of TRH, TSH (Thyroid stimulating hormone), fT3, fT4, insulin, leptin, glucose; thyroperoxidase activity and growth of thyroid gland, food intake, adiposity index were also studied FSE significantly down regulated prepro-TRH mRNA expression; decreased serum TRH, TSH, fT3, fT4 levels, and regressed thyroid gland in FSE-fed normal and diabetic rats than those observed in normal diet-fed control and diabetic rats. FSE decreased (p<0.005-0.001) adiposity index and leptin secretion, increased food intake and body weight in all FSE-fed rats. FSE improved insulin secretion, decreased glucose level but impaired HPT axis in diabetic rats, indicating insulin-independent central hypothyroidism. Results suggested that the dominant signal to hypothalamus suppressing HPT axis is the fall in leptin level which i resulted from decreased adiposity index following FSE feeding. Fenugreek simultaneously having hypoglycaemic and hypothyroidal actions raises questions whether it can be safely used to treat diabetes and/or hyperthyroidism as was suggested by many workers.


Asunto(s)
Diabetes Mellitus Experimental , Hipoglucemiantes/efectos adversos , Hipotiroidismo , Leptina/sangre , Fitoterapia/efectos adversos , Preparaciones de Plantas , Plantas Medicinales/efectos adversos , Trigonella/efectos adversos , Animales , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipotiroidismo/sangre , Hipotiroidismo/inducido químicamente , Preparaciones de Plantas/efectos adversos , Preparaciones de Plantas/farmacología , Ratas , Ratas Wistar , Hormonas Tiroideas/sangre
19.
J Chem Phys ; 146(6): 064306, 2017 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-28201903

RESUMEN

We study the relaxation dynamics of pyrrole after excitation with an 8 eV pump pulse to a state just 0.2 eV below the ionization potential using vacuum ultraviolet/ultraviolet pump probe spectroscopy. Our measurements in conjunction with electronic structure calculations indicate that pyrrole undergoes rapid internal conversion to the ground state in less than 300 fs. We find that internal conversion to the ground state dominates over dissociation.

20.
Mol Reprod Dev ; 81(9): 833-50, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25104294

RESUMEN

Prolonged and strenuous exercise has been proposed as a possible source of male-factor infertility. Forced intensive swimming has also been identified as one source of a dysfunctional male reproduction system. The present study evaluated the possible protective role of α-lipoic acid and N-acetylcysteine (NAC) on intensive swimming-induced germ-cell depletion in adult male rats. Forced exhaustive swimming of 1 hr/day, 6 days/week for 8 consecutive weeks resulted in a significant (P < 0.05) reduction in epididymal sperm; testicular androgenic enzyme activities; and plasma and intra-testicular testosterone; and produced different types of germ cells in the seminiferous epithelium cycle. Conversely, plasma corticosterone levels and sperm-head abnormalities increased. Western-blot analysis showed a considerable decrease in testicular StAR protein expression whereas reverse-transcriptase PCR analysis showed no significant change in cytochrome P450scc (Cyp11a1) gene expression. Significant (P < 0.05) elevation in testicular reactive oxygen species (ROS), lipid peroxidation, protein carbonyl content versus reduction in glucose-6-phosphate dehydrogenase, glutathione peroxidase, glutathione S-transferase, and caspase-3 activities along with a depletion in the glutathione pool, mitochondrial membrane potential (▵ψm ), and intracellular ATP generation. A considerable level of DNA damage in testicular spermatogenic cells were also noted following forced extensive swimming. Alpha-lipoic acid and NAC supplementation prevented the swimming-induced testicular spermatogenic and steroidogenic disorders by lowering ROS generation. We therefore conclude that intensive forced swimming causes germ-cell depletion through the generation of ROS and depletion of steroidogenesis in the testis, which can be protected by the co-administration of α-lipoic acid and NAC.


Asunto(s)
Acetilcisteína/farmacología , Antioxidantes/farmacología , Estrés Oxidativo/efectos de los fármacos , Testículo/efectos de los fármacos , Ácido Tióctico/farmacología , Animales , Biomarcadores/metabolismo , Peso Corporal/efectos de los fármacos , Corticosterona/sangre , Ingestión de Alimentos/efectos de los fármacos , Prueba de Esfuerzo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Tamaño de los Órganos/efectos de los fármacos , Fosfoproteínas/metabolismo , Ratas , Ratas Wistar , Espermatozoides/efectos de los fármacos , Estrés Fisiológico , Natación , Testículo/citología , Testículo/patología , Testosterona/sangre
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