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Experimental Biology and Medicine... Oct 2020Infertility resulting from reproductive impairment is traumatic in families. Exposure to chemicals may play insidious roles not easily connected to infertility. We...
Infertility resulting from reproductive impairment is traumatic in families. Exposure to chemicals may play insidious roles not easily connected to infertility. We examined benzo[a]pyrene (BaP), and -methyl nitrosourea (NMU)-induced ovarian and uterine toxicity and the role of in mitigating toxicity. In a bid to illuminate folk medical claims cloaked in mystery, unearthing lost knowledge, advance natural chemopreventive agents, and report new evidence lacking in the literature attributed to . Although is known to exhibit anticonvulsant, antidiarrheal, antipyretic, antirheumatic, and analgesic effects in humans, its possible roles for mitigating toxicity stemming from inadvertent chemical exposures are reported here. Our findings affirm and further show that abates toxic response incumbent on oxidative damage and inflammatory responses associated with NMU and BaP exposure. Development of phytochemical derived from may serve as a potential natural therapy against chemical toxicities in individuals inadvertently exposed, and promote human health and reproductive satiety.
Topics: Animals; Benzo(a)pyrene; Biomarkers; Body Weight; Fabaceae; Female; Hormones; Inflammation; Methylnitrosourea; Organ Size; Ovary; Oxidation-Reduction; Plant Extracts; Rats, Sprague-Dawley; Uterus; Vincristine; bcl-2-Associated X Protein
PubMed: 32746633
DOI: 10.1177/1535370220947387 -
Biomedicine & Pharmacotherapy =... Jun 2021Combretastatin A-4 (CA-4) received significant interest as a potential anticancer agent in recent years. Several CA-4 analogs were synthesized and investigated to...
UNLABELLED
Combretastatin A-4 (CA-4) received significant interest as a potential anticancer agent in recent years. Several CA-4 analogs were synthesized and investigated to enhance the activity or solve the in vivo decreased activity of CA-4.
AIM
The present study aims to investigate the chemotherapeutic and the antiproliferative effects of the mono and the dual therapy of the newly synthesized CA-4 analogs OMA1520 and OMA1774 against hepatocellularcarcinoma (HCC) induced in male adult rats by N-methylnitrosourea (MNU).
METHODS
50 male rats were divided into 5 groups of 10 animals in each group. Group I: normal healthy control; group II: MNU treated group, group III: MNU animals treated by OMA1520, group IV: MNU animals treated by OMA1774, and group V: MNU animals treated by both OMA1520 and OMA1774. The rats were assessed for liver cancer progression or inhibition by evaluating the histopathological, immunohistochemical, biochemical, and antioxidant enzyme status.
RESULTS
The present work indicated that OMA1520 and OMA1774 possessed substantial chemotherapeutic efficiency against HCC. The histological and immunohistochemical examinations of liver tissues confirmed the biochemical sera data. Also, they diminished the cytotoxic effects of MNU and restored the normal histological hepatic architecture. Both analogs restored the normal levels of liver enzymes and functions and revealed potential antioxidant effects. OMA1520 and OMA1774 reduced the inflammatory and tumor markers' elevated expressions in serum.
CONCLUSION
Substantial evidence in our results suggests that both CA-4 analogs could be possible alternative anticancer agents, and their co-administration provides a synergistic activity.
Topics: Animals; Antineoplastic Agents, Phytogenic; Bibenzyls; Carcinoma, Hepatocellular; HL-60 Cells; Hep G2 Cells; Humans; Liver Neoplasms, Experimental; MCF-7 Cells; Male; Molecular Docking Simulation; Rats; Triazoles
PubMed: 33752057
DOI: 10.1016/j.biopha.2021.111417 -
Stem Cells Translational Medicine Jun 2015Comprehensive analyses comparing individual DNA damage response (DDR) of induced pluripotent stem cells (iPSCs) with neonatal stromal cells with respect to their... (Comparative Study)
Comparative Study
UNLABELLED
Comprehensive analyses comparing individual DNA damage response (DDR) of induced pluripotent stem cells (iPSCs) with neonatal stromal cells with respect to their developmental age are limited. The imperative necessity of providing developmental age-matched cell sources for meaningful toxicological drug safety assessments in replacement of animal-based testing strategies is evident. Here, DDR after radiation or treatment with N-methyl-N-nitrosurea (MNU) was determined in iPSCs compared with neonatal and bone marrow stromal cells. Neonatal and adult stromal cells showed no significant morphologically detectable cytotoxicity following treatment with 1 Gy or 1 mM MNU, whereas iPSCs revealed a much higher sensitivity. Foci analyses revealed an effective DNA repair in stromal cell types and iPSCs, as reflected by a rapid formation and disappearance of phosphorylated ATM and γH2AX foci. Furthermore, quantitative polymerase chain reaction analyses revealed the highest basic expression level of DDR and repair-associated genes in iPSCs, followed by neonatal stromal cells and adult stromal cells with the lowest expression levels. In addition, the influence of genotoxic stress prior to and during osteogenic differentiation of neonatal and adult stromal cells was analyzed applying common differentiation procedures. Experiments presented here suggest a developmental age-dependent basic expression level of genes involved in the processing of DNA damage. In addition a differentiation-dependent downregulation of repair genes was observed during osteogenesis. These results strongly support the requirement to provide adequate cell sources for toxicological in vitro drug testing strategies that match to the developmental age and differentiation status of the presumptive target cell of interest.
SIGNIFICANCE
The results obtained in this study advance the understanding of DNA damage processing in human neonatal stromal cells as compared with adult stromal cells and induced pluripotent stem cells (iPSCs). The data suggest developmental age-dependent differences in DNA damage repair capacity. In iPSCs (closest to embryonic stem cells), the highest expression level of DNA damage response and repair genes was found, followed by neonatal stromal cells and adult stromal cells with the lowest overall expression. In addition, a differentiation-dependent downregulation of repair capacity was observed during osteogenic differentiation in neonatal stromal cells. Notably, the impact of genotoxic stress on osteogenic differentiation depended on the time the genotoxic insult took place and, moreover, was agent-specific. These results strongly support the necessity of offering and establishing adequate cell sources for informative toxicological testing matching to the developmental age and differentiation status of the respective cell of interest.
Topics: Adult; Alkylating Agents; Ataxia Telangiectasia Mutated Proteins; Cell Differentiation; DNA Damage; Drug Evaluation, Preclinical; Female; Histones; Humans; Induced Pluripotent Stem Cells; Infant, Newborn; Male; Methylnitrosourea; Osteogenesis; Phosphorylation; Stromal Cells; X-Rays
PubMed: 25900727
DOI: 10.5966/sctm.2014-0209 -
Contrast Media & Molecular Imaging 2019D--Tocopheryl polyethylene glycol 1000 succinate (TPGS) is a Food and Drug Administration (FDA) approved biomaterial that can form nanosized micelles in aqueous... (Comparative Study)
Comparative Study
D--Tocopheryl polyethylene glycol 1000 succinate (TPGS) is a Food and Drug Administration (FDA) approved biomaterial that can form nanosized micelles in aqueous solution. TPGS micelles stand as an interesting system to perform drug delivery as they can carry lipophilic drugs and overcome P glycoprotein efflux as well. Therefore, TPGS micelles combined with other copolymers have been reported in many cancer research studies as a carrier for therapeutic drugs. Their ability to reach tumoral tissue can also be exploited to develop imaging agents with diagnostic application. A radiolabeling method with Tc for TPGS nanosized micelles and their biodistribution in a healthy animal model as well as their pharmacokinetics and radiolabeling stability was previously reported. The aim of this work was to evaluate the performance of this radioactive probe as a diagnostic imaging agent compared to routinely available SPECT radiopharmaceutical, Tc-sestamibi. A small field of view gamma camera was used for scintigraphy studies using radiolabeled TPGS micelles in two animal models of breast cancer: syngeneic 4T1 murine cell line (injected in BALB/c mice) and chemically NMU-induced (Sprague-Dawley rats). radioactivity accumulation in organs of interest was measured by a solid scintillation counter, and a semiquantitative analysis was performed over acquired images as well. Results showed an absence of tumoral visualization in 4T1 model for both radioactive probes by gamma camera imaging. On the contrary, NMU-induced tumors had a clear tumor visualization by scintigraphy. A higher tumor/background ratio and more homogeneous uptake were found for radiolabeled TPGS micelles compared to Tc-sestamibi. In conclusion, Tc-radiolabeled TPGS micelles might be a potential SPECT imaging probe for diagnostic purposes.
Topics: Animals; Breast Neoplasms; Drug Evaluation, Preclinical; Drug Stability; Female; Humans; Mammary Neoplasms, Experimental; Methylnitrosourea; Mice, Inbred BALB C; Mice, Inbred C3H; Micelles; Nanostructures; Radiopharmaceuticals; Rats, Sprague-Dawley; Technetium Tc 99m Sestamibi; Tissue Distribution; Tomography, Emission-Computed, Single-Photon; Vitamin E
PubMed: 31178670
DOI: 10.1155/2019/4087895 -
Journal of Visualized Experiments : JoVE Oct 2014Retinal degenerative diseases, e.g. retinitis pigmentosa, with resulting photoreceptor damage account for the majority of vision loss in the industrial world. Animal...
Retinal degenerative diseases, e.g. retinitis pigmentosa, with resulting photoreceptor damage account for the majority of vision loss in the industrial world. Animal models are of pivotal importance to study such diseases. In this regard the photoreceptor-specific toxin N-methyl-N-nitrosourea (MNU) has been widely used in rodents to pharmacologically induce retinal degeneration. Previously, we have established a MNU-induced retinal degeneration model in the zebrafish, another popular model system in visual research. A fascinating difference to mammals is the persistent neurogenesis in the adult zebrafish retina and its regeneration after damage. To quantify this observation we have employed visual acuity measurements in the adult zebrafish. Thereby, the optokinetic reflex was used to follow functional changes in non-anesthetized fish. This was supplemented with histology as well as immunohistochemical staining for apoptosis (TUNEL) and proliferation (PCNA) to correlate the developing morphological changes. In summary, apoptosis of photoreceptors occurs three days after MNU treatment, which is followed by a marked reduction of cells in the outer nuclear layer (ONL). Thereafter, proliferation of cells in the inner nuclear layer (INL) and ONL is observed. Herein, we reveal that not only a complete histological but also a functional regeneration occurs over a time course of 30 days. Now we illustrate the methods to quantify and follow up zebrafish retinal de- and regeneration using MNU in a video-format.
Topics: Animals; Apoptosis; Methylnitrosourea; Photoreceptor Cells; Regeneration; Retina; Retinal Degeneration; Zebrafish
PubMed: 25350292
DOI: 10.3791/51909 -
PloS One 2023We aimed to verify whether the intravitreal injection of small molecule compounds alone can create photoreceptor cells in mouse models of retinal degeneration. Primary...
We aimed to verify whether the intravitreal injection of small molecule compounds alone can create photoreceptor cells in mouse models of retinal degeneration. Primary cultured mouse Müller cells were stimulated in vitro with combinations of candidate compounds and the rhodopsin expression was measured on day 7 using polymerase chain reaction and immunostaining. We used 6-week-old N-methyl-N-nitrosourea-treated and 4-week-old rd10 mice as representative in vivo models of retinal degeneration. The optimal combination of compounds selected via in vitro screening was injected into the vitreous and the changes in rhodopsin expression were investigated on day 7 using polymerase chain reaction and immunostaining. The origin of rhodopsin-positive cells was also analyzed via lineage tracing and the recovery of retinal function was assessed using electroretinography. The in vitro mRNA expression of rhodopsin in Müller cells increased 30-fold, and 25% of the Müller cells expressed rhodopsin protein 7 days after stimulation with a combination of 4 compounds: transforming growth factor-β inhibitor, bone morphogenetic protein inhibitor, glycogen synthase kinase 3 inhibitor, and γ-secretase inhibitor. The in vivo rhodopsin mRNA expression and the number of rhodopsin-positive cells in the outer retina were significantly increased on day 7 after the intravitreal injection of these 4 compounds in both N-methyl-N-nitrosourea-treated and rd10 mice. Lineage tracing in td-Tomato mice treated with N-methyl-N-nitrosourea suggested that the rhodopsin-positive cells originated from endogenous Müller cells, accompanied with the recovery of the rhodopsin-derived scotopic function. It was suggested that rhodopsin-positive cells generated by compound stimulation contributes to the recovery of retinal function impaired by degeneration.
Topics: Mice; Animals; Retinal Degeneration; Rhodopsin; Intravitreal Injections; Methylnitrosourea; Retina; Disease Models, Animal; Electroretinography; RNA, Messenger
PubMed: 36821627
DOI: 10.1371/journal.pone.0282174 -
Anais Da Academia Brasileira de Ciencias May 2017The development of DBA/2J mouse strain embryos is nearly 12 h - or 6 somite pairs - delayed as compared to the outbred NMRI mouse embryos of the same age on gestation... (Comparative Study)
Comparative Study
The development of DBA/2J mouse strain embryos is nearly 12 h - or 6 somite pairs - delayed as compared to the outbred NMRI mouse embryos of the same age on gestation days (GD) 8-12. To evaluate inter-strain differences in susceptibility to teratogens, dams were treated with methylnitrosourea (MNU, 5 mg/kg body weight i.p.) on defined gestation days (NMRI: GD 9, 91/2 or 10; DBA/2J: GD 10 or 101/2). Skeletal anomalies produced by MNU on both mouse strains varied with the GD of treatment. The pattern of anomalies produced by MNU on a given GD markedly differed between the two mouse strains, yet they were similar -with a few exceptions- when exposures at equivalent embryonic stages are compared. Findings from this study indicated that strain-dependent differences in the developmental stage of mouse embryos of the same gestational age occur, a possibility that has been often neglected when inter-strain differences in susceptibility to developmental toxicants are interpreted.
Topics: Animals; Embryo, Mammalian; Embryonic Development; Female; Methylnitrosourea; Mice; Mice, Inbred DBA; Pregnancy; Skeleton; Somites; Teratogens
PubMed: 28562829
DOI: 10.1590/0001-3765201720160483 -
Cell Death and Differentiation Mar 2021Photoreceptor apoptosis is recognized as one key pathogenesis of retinal degeneration, the counteraction of which represents a promising approach to safeguard visual...
Photoreceptor apoptosis is recognized as one key pathogenesis of retinal degeneration, the counteraction of which represents a promising approach to safeguard visual function. Recently, mesenchymal stem cell transplantation (MSCT) has demonstrated immense potential to treat ocular disorders, in which extracellular vesicles (EVs), particularly exosomes, have emerged as effective ophthalmological therapeutics. However, whether and how MSCT protects photoreceptors against apoptotic injuries remains largely unknown. Here, we discovered that intravitreal MSCT counteracted photoreceptor apoptosis and alleviated retinal morphological and functional degeneration in a mouse model of photoreceptor loss induced by N-methyl-N-nitrosourea (MNU). Interestingly, effects of MSCT were inhibited after blockade of exosomal generation by GW4869 preconditioning. Furthermore, MSC-derived exosomal transplantation (EXOT) effectively suppressed MNU-provoked photoreceptor injury. Notably, therapeutic efficacy of MSCT and EXOT on MNU-induced retinal degeneration was long-lasting as photoreceptor preservance and retinal maintenance were detected even after 1-2 months post to injection for only once. More importantly, using a natural occurring retinal degeneration model caused by a nonsense mutation of Phosphodiesterase 6b gene (Pde6b), we confirmed that MSCT and EXOT prevented photoreceptor loss and protected long-term retinal function. In deciphering therapeutic mechanisms regarding potential exosome-mediated communications, we identified that miR-21 critically maintained photoreceptor viability against MNU injury by targeting programmed cell death 4 (Pdcd4) and was transferred from MSC-derived exosomes in vivo for functional regulation. Moreover, miR-21 deficiency aggravated MNU-driven retinal injury and was restrained by EXOT. Further experiments revealed that miR-21 mediated therapeutic effects of EXOT on MNU-induced photoreceptor apoptosis and retinal dysfunction. These findings uncovered the efficacy and mechanism of MSCT-based photoreceptor protection, indicating exosomal miR-21 as a therapeutic for retinal degeneration.
Topics: Animals; Apoptosis; Disease Models, Animal; Female; Male; Mesenchymal Stem Cell Transplantation; Methylnitrosourea; Mice; Mice, Inbred C57BL; MicroRNAs; Photoreceptor Cells, Vertebrate; Retina; Retinal Degeneration
PubMed: 33082517
DOI: 10.1038/s41418-020-00636-4 -
Cancer Science Jun 2024Rev1 has two important functions in the translesion synthesis pathway, including dCMP transferase activity, and acts as a scaffolding protein for other polymerases...
Rev1 has two important functions in the translesion synthesis pathway, including dCMP transferase activity, and acts as a scaffolding protein for other polymerases involved in translesion synthesis. However, the role of Rev1 in mutagenesis and tumorigenesis in vivo remains unclear. We previously generated Rev1-overexpressing (Rev1-Tg) mice and reported that they exhibited a significantly increased incidence of intestinal adenoma and thymic lymphoma (TL) after N-methyl-N-nitrosourea (MNU) treatment. In this study, we investigated mutagenesis of MNU-induced TL tumorigenesis in wild-type (WT) and Rev1-Tg mice using diverse approaches, including whole-exome sequencing (WES). In Rev1-Tg TLs, the mutation frequency was higher than that in WT TL in most cases. However, no difference in the number of nonsynonymous mutations in the Catalogue of Somatic Mutations in Cancer (COSMIC) genes was observed, and mutations involved in Notch1 and MAPK signaling were similarly detected in both TLs. Mutational signature analysis of WT and Rev1-Tg TLs revealed cosine similarity with COSMIC mutational SBS5 (aging-related) and SBS11 (alkylation-related). Interestingly, the total number of mutations, but not the genotypes of WT and Rev1-Tg, was positively correlated with the relative contribution of SBS5 in individual TLs, suggesting that genetic instability could be accelerated in Rev1-Tg TLs. Finally, we demonstrated that preleukemic cells could be detected earlier in Rev1-Tg mice than in WT mice, following MNU treatment. In conclusion, Rev1 overexpression accelerates mutagenesis and increases the incidence of MNU-induced TL by shortening the latency period, which may be associated with more frequent DNA damage-induced genetic instability.
Topics: Animals; Methylnitrosourea; Mice; Thymus Neoplasms; Mutagenesis; Nucleotidyltransferases; DNA-Directed DNA Polymerase; Mice, Transgenic; Lymphoma; Mutation; Exome Sequencing
PubMed: 38572512
DOI: 10.1111/cas.16159 -
Molecules (Basel, Switzerland) Dec 2019In the present study, we examined the potent retinoprotective effects of an ethanol-based extract of (AJE) and its active ingredient, aucubin, on -methyl--nitrosourea...
In the present study, we examined the potent retinoprotective effects of an ethanol-based extract of (AJE) and its active ingredient, aucubin, on -methyl--nitrosourea (MNU)-induced retinal degeneration in mice. Retinal degeneration was induced by an intraperitoneal injection of MNU (60 mg/kg). AJE (250 mg/kg) and aucubin (15 mg/kg) were orally administered for 1 week after the MNU injection. Electroretinography (ERG) and histological examinations were performed. Retinal apoptosis and oxidative DNA damage were also quantified. The retinoprotective abilities of AJE and aucubin were also assessed in primary cultured retinal cells. Morphologically, MNU induced a remarkable decrease in the outer nuclear layer, which contains photoreceptor cells. However, this layer was well preserved in the AJE- and aucubin-administered mice. The ERG responses significantly decreased in both a- and b-wave amplitudes in the MNU-injected mice. In the AJE and aucubin-treated mice, ERG responses were significantly increased. In addition, a terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) assay and immunohistochemical staining for 8-hydroxydeoxyguanosine (8-OHdG) revealed that both AJE and aucubin attenuated MNU-induced photoreceptor cell apoptosis and oxidative DNA damage. Furthermore, the in vitro assay also showed that AJE and aucubin have potent anti-oxidative and anti-apoptotic activities in primary cultured retinal cells. These results indicate that AJE and aucubin have potent retinoprotective effects, and that this retinoprotective activity is as a result of the potency of the bioactive compound, aucubin. These pharmacological characteristics suggest the additional application of AJE or aucubin in the treatment of patients with retinal degenerative diseases.
Topics: Animals; Apoptosis; Cell Survival; Cells, Cultured; DNA Damage; Disease Models, Animal; Iridoid Glucosides; Magnoliopsida; Male; Methylnitrosourea; Mice, Inbred C57BL; Oxidative Stress; Photoreceptor Cells, Vertebrate; Plant Extracts; Retina; Retinal Degeneration
PubMed: 31817154
DOI: 10.3390/molecules24244437