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1.
Reprod Toxicol ; 124: 108551, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280688

RESUMO

Gestational exposure to the anticonvulsant drug valproic acid (VPA) is associated with congenital malformations and neurodevelopmental disorders through its action as a histone deacetylase inhibitor. VPA can elicit placental toxicity and affect placental growth and development. The objective of this study was to evaluate the impact of maternal exposure to VPA on the mouse placenta following exposure on gestational day (GD) 13 since previous studies have shown that mice exposed at this time during gestation give birth to offspring with an autism spectrum disorder-like phenotype. We exposed CD-1 dams to a teratogenic dose (600 mg/kg) of VPA or saline on GD13 and assessed fetoplacental growth and development on GD18. We evaluated epigenetic modifications, including acetylated histone H4 (H4ac), methylated H3K4 (H3K4me2) using immunohistochemistry, and global DNA methylation in the placenta at 1, 3, and 24 h following maternal exposure on GD13. In utero exposure to VPA on GD13 significantly decreased placental weight and increased fetal resorptions. Moreover, VPA significantly increased the staining intensity of histone H4 acetylation and H3K4 di-methylation across the placenta at 1 and 3 h post maternal dose. Our results also demonstrate that VPA significantly decreased global DNA methylation levels in placental tissue. These results show that gestational exposure to VPA interferes with placental growth and elicits epigenetic modifications, which may play a vital role in VPA-induced developmental toxicity.


Assuntos
Transtorno do Espectro Autista , Ácido Valproico , Gravidez , Feminino , Camundongos , Animais , Ácido Valproico/toxicidade , Histonas/metabolismo , Placenta/metabolismo , Epigênese Genética
2.
J Pak Med Assoc ; 74(1): 126-128, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38219179

RESUMO

The purpose of this study was to determine and compare the effects of trunk stabilisation and activation exercises on pain and disability in postpartum lumbo-pelvic pain. It was a randomised clinical trial (ClinicalTrials.gov: NCT05490810). Twenty-eight females with lumbo-pelvic pain were randomly allocated to two groups with 14 patients in each group. Group A was treated with trunk stabilisation exercises and Group B was treated with trunk activation exercises, three times a week for eight weeks. Numeric pain rating scale was used to measure the intensity of pain. Disability was assessed through Oswestry disability index (ODI). Both the groups were evaluated before and at the end of the last treatment session. Data was analysed by SPSS 21. There was a significant difference between trunk stabilisation versus activation exercises on pain and disability in postpartum lumbo-pelvic pain with p<0.05 in Group A patients. The trunk stabilisation exercises were more effective for the treatment of lumbo-pelvic pain in postpartum females.


Assuntos
Terapia por Exercício , Dor Pélvica , Feminino , Humanos , Dor Pélvica/terapia , Período Pós-Parto , Exercício Físico , Pelve
3.
Chemosphere ; 339: 139662, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37499801

RESUMO

A facile and eco-friendly synthesis of PW12/TiO2@MgCO3 hollow tubes (PW12·âˆ¼· H3[PW12O40] = polyoxometalate) using a soluble and reusable MgCO3·3H2O micro-rods template was reported for the first time. The resultant hollow tubes were characterized by Fourier transform infrared spectroscopy (FT-IR), UV-visible spectroscopy, powder X-ray diffraction (PXRD), energy-dispersive X-ray spectroscopy (EDX), and scanning electron microscopy (SEM), which indicated that the [PW12O40]3- structure remained intact within the hollow tubes. Furthermore, the specific surface area (88.982 m2/g) and average pore size (2.6 nm) of the PW12/TiO2@MgCO3 hollow tubes were calculated using the Brunauer-Emmett-Teller (BET) analysis. This study explored the catalytic performance of PW12/TiO2@MgCO3 hollow tubes using a three-level Box-Behnken design (BBD), through which optimization curves were designed. The desulfurization of model fuel using hollow tubes was optimally performed when the catalyst dose, time, temperature, and oxidant/sulfur (O/S) were 20-80 gm, 80-120 min, 25-80 °C and 3-8 molar ratio, respectively. These results were further processed, and the experiments were replicated twenty-nine times using a model based on two quadratic polynomials to create a response surface methodology (RSM). This permits a mathematical correlation linking the desulfurization and experimental parameters. The optimal performance of reaction mixture was evaluated to be 80 mg for catalyst concentration, 25 °C of temperature, reaction time of 100 min, and 5.5 for oxidant/sulfur molar ratio from 20 mL of octane simulation oil containing 350 ppm dibenzothiophene (DBT). The predicted desulfurization rate of the model fuel under these optimal conditions was 95.3%. The correspondence between the experimental results and predicted values was verified based on regression analysis, with an R2 value greater than 0.99. These hollow tubes could be used for their desulfurization properties ten times a row without significantly reducing catalytic activity.


Assuntos
Oxidantes , Enxofre , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Oxidativo
4.
Birth Defects Res ; 115(3): 338-347, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36369707

RESUMO

INTRODUCTION: Triphenyl phosphate (TPHP) is a chemical flame retardant and plasticizer which is added to consumer and industrial products. The developmental origins of health and disease hypothesis postulate that in utero exposures can have later-in-life effects on the developing fetus and can alter fetal gene expression. This study aimed to determine whether epigenetic modifications occurred following in utero TPHP exposure in mice and whether these changes were dose and/or sex-dependent. METHODS: Pregnant C57Bl/6 mice were treated with 0, 5, 25, or 50 mg/kg of TPHP on gestational days (GD) 8, 10, 12, and 14 via intraperitoneal injection and fetal livers were collected on GD 19. Changes in the levels of acetylation of H3 and H4, as well as methylation of H3K9 and global DNA methylation were assessed in the fetal livers by western blot. RESULTS: Results showed that there was a significant decrease in fetal DNA methylation following in utero exposure to 50 mg/kg TPHP compared to the control (0 mg/kg) independent of the sex of the fetus. While there were no significant alterations compared to controls in any histone modifications at any dose or sex following in utero TPHP exposure, we did note a decrease (t test, p = .025) in the levels of acetylated H3 in males versus females following a maternal dose of 25 mg/kg. The monomethylated H3K9 levels were also increased in females versus males following exposure to TPHP at 5 mg/kg (p = .018) and 25 mg/kg (p = .027) when analyzed via unpaired t tests, although not significantly different from controls. DISCUSSION: The results suggest that gestational TPHP exposure can induce epigenetic modifications in murine fetal tissue. Specifically, global DNA methylation levels were downregulated in response to TPHP. Additionally, males appear to be more sensitive to TPHP-induced histone modifications than females. These data support the need for further studies investigating the impacts of gestational TPHP exposure on the developing fetus.


Assuntos
Metilação de DNA , Epigênese Genética , Gravidez , Masculino , Feminino , Animais , Camundongos , Organofosfatos/toxicidade , Camundongos Endogâmicos C57BL , Fígado
5.
Chemosphere ; 313: 137418, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36460159

RESUMO

Mixed Matrix Membranes have gained significant attention over the past few years due to their diverse applications, unique hybrid inorganic filler and polymeric properties. In this article, the impregnation of nano-hybrid filler (polyoxometalates (∼POMs) encapsulated into the metal-organic framework (MOF) âˆ¼ PMOF) on the polysulfone membrane (∼PSF) was done, resulting in a mix matrix membrane (∼PMOF@PSF). The developed structure was characterized by Fourier transform infrared (FT-IR), powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopes (TEM). The results confirmed that the nano-hybrid filler was successfully fabricated on the surface of PSF. Different loading ratios of nano-hybrid filler (5%, 10%, 20%, 30%, and 40%) were used for impregnation. The study's objective was to enhance catalytic performance using optimization curves designed using a three-level Box-Behnken Design (BBD) simulation. The photodegradation of Methylene Blue (∼MB) was studied against PMOF@PSF30% and was found to perform optimally when the concentration of catalyst, time of degradation, and temperature were 0.05-0.15 gm, 40-120 min, and 30-70 °C respectively. These experiments were replicated 15 times, and obtained results were further processed using a two-quadratic polynomial model to develop response surface methodology (RSM), which allowed for a functional relationship between the decolorization and experimental parameters. The optimal performance of the reaction mixture was calculated to be 0.15 gm for concentration, 70 °C for temperature, with an 80 min reaction time. Under these optimal conditions, the predicted decolorization of MB was 98.09%. Regression analysis with R2 > 0.99 verified the fit of experimental results with predicted values. The PMOF@PSF PSF30% demonstrated excellent reusability as its dye degradation properties were significantly unaffected after ten cycles.


Assuntos
Azul de Metileno , Modelos Estatísticos , Espectroscopia de Infravermelho com Transformada de Fourier , Fotólise , Azul de Metileno/química , Excipientes , Sulfonas
6.
Birth Defects Res ; 114(16): 1003-1013, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35332709

RESUMO

The study of human brain development and neurodevelopmental defects has remained challenging so far due to unique, specific, and complex underlying processes. Recent advances in the technologies and protocols of in vitro human brain organoid development have led to immense possibilities of understanding these processes. Human brain organoids are stem-cell derived three-dimensional in vitro tissues that resemble the developing fetal brain. Major advances in stem cell techniques pioneering the development of in vitro human brain development include reprogramming human somatic cells into induced pluripotent cells (iPSCs) followed by the targeted differentiation of iPSCs into the cells of three embryonic germ cell layers. The neural progenitor cells produced by the directed differentiation of iPSCs undergo some level of self-organization to generate in vitro human brain like tissue. A three-dimensional differentiation approach applied to create region-specific brain organoids has successfully led to develop highly specialized cortical, forebrain, pallium, and subpallium in vitro human brain organoid models. These stem cell-based brain organoids are novel models to study human brain development, neurodevelopmental defects, chemical toxicity testing, and drug repurposing screening. This review focuses on the fundamentals of brain organoid development and applications. The novel applications of using cortical organoids in understanding the mechanisms of Zika virus-induced microcephaly, congenital microcephaly, and lissencephaly are also discussed.


Assuntos
Microcefalia , Células-Tronco Neurais , Infecção por Zika virus , Zika virus , Encéfalo , Humanos , Organoides
7.
Placenta ; 112: 141-152, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34352490

RESUMO

INTRODUCTION: Valproic acid (VPA) is an effective anti-epileptic drug clinically used to treat seizures, bipolar disorders and neuropathic pain in women of reproductive age. Current approval of VPA for psychiatric conditions and migraine has increased the number of VPA exposed pregnancies. VPA crosses the placental barrier and induces birth defects in about 10% of exposed pregnancies. In addition, VPA exposure results in neurodevelopmental disorders in children without any overt birth defects. The current study was designed to investigate the effects of in utero VPA exposure on fetoplacental growth in a mouse model. METHODS: Pregnant CD-1 dams were exposed to a single teratogenic dose of 400 mg/kg VPA or saline via subcutaneous injection on gestational day (GD) 9 and fetuses were harvested on GD 13, 15, 17 and 19, respectively. Resorptions, gross malformations, fetal weight, fetal head weight, fetal crown-rump length, fetal head transverse and anteroposterior diameters, placental weight and placental diameter were noted. RESULTS: VPA exposure led to multiple external deformities including exencephaly, open eye defect, subcutaneous hemorrhage and underdevelopment of tail. All fetoplacental growth parameters fetal weight, fetal head weight, fetal crown-rump length, placental weight and placental diameter were significantly reduced in VPA-exposed fetuses with and without congenital malformations such as exencephaly, compared to control fetuses. DISCUSSION: In conclusion, the effects of in utero VPA exposure on fetal and placental growth persisted throughout pregnancy and our results suggest that the effects of VPA on placental growth may play a role in VPA-induced toxicity.


Assuntos
Anormalidades Induzidas por Medicamentos/patologia , Anticonvulsivantes/efeitos adversos , Desenvolvimento Fetal/efeitos dos fármacos , Feto/patologia , Ácido Valproico/efeitos adversos , Anormalidades Induzidas por Medicamentos/etiologia , Animais , Feminino , Feto/efeitos dos fármacos , Masculino , Exposição Materna , Camundongos , Gravidez
8.
Placenta ; 107: 31-40, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33735658

RESUMO

INTRODUCTION: Valproic acid (VPA), a widely prescribed antiepileptic drug and an effective treatment for bipolar disorder and neuropathic pain, results in multiple developmental defects following in utero exposure. Uterine decidua provides nutritional and physical support during implantation and early embryonic development. Perturbations in the molecular mechanisms within decidual tissue during early pregnancy might affect early embryonic growth, result in early pregnancy loss or cause complications in the later gestational stage. VPA is a known histone deacetylase inhibitor and epigenetic changes such as histone hyperacetylation and methylation have been proposed as a mechanism of VPA-induced teratogenesis. METHODS: This study investigated the effects of in utero VPA exposure on histone modifications in murine decidual tissue. Pregnant CD-1 mice were exposed to 400 mg/kg VPA or saline on GD9 via subcutaneous injection. Decidual tissue from each gestational sac was harvested at 1, 3 and 6 h following exposure. Levels of acetylated histones H3, H4 and H3K56, as well as methylated histones H3K9 and H3K27 were acid extracted and assessed by western blotting followed by acid histone extraction. RESULTS: VPA exposure induced a significant increase (p < 0.05) in the levels of acetylated H3 at 1, 3 h; acetylated H4 at 1, 3 and 6 h and trimethylated H3K9 at 6 h. In contrast, no significant perturbations were noted in the levels of monomethylated H3K9, trimethylated H3K27 and acetylated H3K56. DISCUSSION: The results from this study suggest that VPA-induced decidual histone modifications might play an important role as a mechanism of VPA-induced teratogenesis during early embryonic growth.


Assuntos
Decídua/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Ácido Valproico/farmacologia , Animais , Decídua/metabolismo , Feminino , Histonas/metabolismo , Camundongos , Gravidez
9.
Neurotoxicol Teratol ; 83: 106941, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33212164

RESUMO

Nuclear factor kappa B (NF-κB) is a heterodimer of protein subunits p65 and p50, that regulates the expression of a large number of genes related to cell growth and proliferation. The p65 subunit is activated after phosphorylation by Pim-1, while the p50 subunit is the cleaved product of its precursor molecule p105. Valproic acid (VPA), an antiepileptic drug, is a known teratogen and its exposure during pregnancy is associated with 1-2% of neural tube defects in the offspring. The current study aimed at investigating the effects of in utero VPA exposure on the key components of the NF-κB signaling pathway including p65, p50, and Pim-1 in CD-1 mouse embryos during the critical period of neural tube closure. Here we report that p65, Pim-1 and p105/p50 mRNA were significantly (p < 0.05) downregulated at 1 and 3 h following in utero exposure to a teratogenic dose (400 mg/kg) of VPA in gestational day (GD)9 exposed embryos. At GD13 heads of control, non-exencephalic and exencephalic embryos were used for analysis and we found significant upregulation of p65 protein expression in non-exencephalic GD13 heads while p50 protein levels were significantly downregulated in both non-exencephalic and exencephalic groups. On the other hand, p65 and p50 protein levels remained unchanged in the nuclear extracts of the VPA-exposed non-exencephalic and exencephalic GD13 embryo heads. The reported results suggest that VPA exposure perturbates p65, p105/p50, Pim-1 transcript and p65/p50 protein levels in mouse embryos.


Assuntos
NF-kappa B/metabolismo , Tubo Neural/efeitos dos fármacos , Tubo Neural/embriologia , Ácido Valproico/toxicidade , Animais , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/toxicidade , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Masculino , Troca Materno-Fetal , Camundongos , NF-kappa B/genética , Subunidade p50 de NF-kappa B/genética , Subunidade p50 de NF-kappa B/metabolismo , Tubo Neural/metabolismo , Defeitos do Tubo Neural/induzido quimicamente , Defeitos do Tubo Neural/embriologia , Defeitos do Tubo Neural/metabolismo , Neurotoxinas/administração & dosagem , Neurotoxinas/toxicidade , Neurulação/efeitos dos fármacos , Neurulação/fisiologia , Gravidez , Proteínas Proto-Oncogênicas c-pim-1/genética , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Ácido Valproico/administração & dosagem
10.
Reprod Toxicol ; 95: 86-94, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32445665

RESUMO

Valproic acid (VPA), an antiepileptic and mood-stabilizing drug, is prescribed to women of reproductive age. VPA is associated with a 1-2% increase in neural tube defects in offspring following gestational exposure and results in epigenetic modifications induced by perturbations in transcription cofactors. Cbp and p300, two transcription cofactors, play key roles in embryonic neural development. p300 is a downstream target of Akt, a protein kinase B associated with cell survival and anti-apoptotic mechanisms, as part of the Akt-p300 axis. We examined the effects of in utero VPA exposure on Cbp, p300, and Akt in gestational day (GD)9, GD10 and GD13 CD-1 mouse embryos following a teratogenic maternal dose of 400 mg/kg. Embryos were collected at 0, 1, 3 and 6 h post-dosing on GD9, 24 h post-dosing on GD10 and on GD13. GD10 embryos were grouped according to the status of neural tube closure in control, closed and open groups. GD13 heads were grouped as control, exposed but non-exencephalic and exencephalic. Our data indicate that Cbp, p300 and Akt mRNA levels were downregulated at 1 and 3 h post-exposure in GD9 embryos while Cbp and p300 protein levels remained stable. Akt protein levels were significantly increased 1 h post-exposure. No significant changes were observed in either mRNA or protein expression in embryos with closed or open neural tubes compared to the control group at GD10. Downregulated expression of Cbp, p300, and Akt may play a key role in VPA-induced neural tube defects considering their vitally important role in embryonic development.


Assuntos
Anormalidades Induzidas por Medicamentos/metabolismo , Proteína de Ligação a CREB , Proteína p300 Associada a E1A , Defeitos do Tubo Neural/metabolismo , Proteínas Proto-Oncogênicas c-akt , Ácido Valproico , Anormalidades Induzidas por Medicamentos/genética , Animais , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/metabolismo , Regulação para Baixo , Proteína p300 Associada a E1A/genética , Proteína p300 Associada a E1A/metabolismo , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/metabolismo , Camundongos , Defeitos do Tubo Neural/induzido quimicamente , Defeitos do Tubo Neural/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo
11.
Birth Defects Res ; 112(7): 555-568, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32134217

RESUMO

Valproic acid (VPA), a widely prescribed antiepileptic drug and an effective treatment for psychiatric disorders, is teratogenic causing neural tube defects (NTDs) and other defects in the exposed embryo. Signal transducer and activator of transcription 3 (Stat3) is a transcription factor that is activated via tyrosine phosphorylation. Stat3, as well as its active form (pYStat3), is expressed during neural tube closure in murine development. This study investigated the effects of in utero VPA exposure on embryonic Stat3 mRNA and protein expression during the critical period of neural tube closure in CD-1 mouse embryos. Following the exposure of CD-1 pregnant mice to the teratogenic dose of 400 mg/kg VPA or saline on gestational day (GD) 9, embryos were harvested at 1, 3, 6, or 24 hr and on GD13. Stat3 mRNA levels remained unchanged at all time points. Total Stat3 protein levels were significantly (p < .05) increased in GD9 embryos at 1 and 6 hr post-exposure and in GD13 exposed nonexencephalic and exencephalic embryo heads. In contrast, phosphorylated Stat3 levels were significantly (p < .05) downregulated in GD9 embryos at the 3 and 6 hr time points with an overall trend of downregulation in the GD10 and GD13 groups. Total and phosphorylated Stat3 protein levels remained unchanged in nuclear extracts of the exposed nonexencephalic and exencephalic GD13 embryo heads. The reported significant downregulation of phosphorylated Stat3 levels suggests its possible role in VPA-induced NTDs in mouse embryos.


Assuntos
Defeitos do Tubo Neural , Ácido Valproico , Animais , Feminino , Camundongos , Defeitos do Tubo Neural/induzido quimicamente , Neurulação , Gravidez , Fator de Transcrição STAT3/genética , Teratogênicos/toxicidade , Ácido Valproico/toxicidade
12.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 2): o165, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23424453

RESUMO

In the title compound, C(18)H(16)ClN(3)O(2)S, the dihedral angle between the aromatic rings is 4.81 (2)° and the alkyl chain takes on an extended conformation [N-C-C-C = 179.2 (4)°]. The conformation of the thia-zine ring is an envelope, with the S atom displaced by -0.805 (3) Šfrom the mean plane of the other five atoms (r.m.s. deviation = 0.046 Å). The Cl atom is an axial conformation and is displaced by 1.761 (4) Šfrom the thia-zine ring plane. In the crystal, inversion dimers linked by pairs of C-H⋯O inter-actions generate R(2) (2)(20) loops and further C-H⋯O hydrogen bonds link the dimers into (001) sheets. Weak aromatic π-π stacking inter-actions [centroid-centroid separations = 3.870 (3) and 3.883 (3) Å] are also observed.

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