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Some Ts in nuclear DNA of trypanosomes and Leishmania are hydroxylated and glucosylated to yield base J (ß-D-glucosyl-hydroxymethyluracil). In Leishmania, about 99% of J is located in telomeric repeats. We show here that most of the remaining J is located at chromosome-internal RNA polymerase II termination sites. This internal J and telomeric J can be reduced by a knockout of J-binding protein 2 (JBP2), an enzyme involved in the first step of J biosynthesis. J levels are further reduced by growing Leishmania JBP2 knockout cells in BrdU-containing medium, resulting in cell death. The loss of internal J in JBP2 knockout cells is accompanied by massive readthrough at RNA polymerase II termination sites. The readthrough varies between transcription units but may extend over 100 kb. We conclude that J is required for proper transcription termination and infer that the absence of internal J kills Leishmania by massive readthrough of transcriptional stops.
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Glucósidos/metabolismo , Leishmania/genética , Leishmania/metabolismo , Transcripción Genética , Uracilo/análogos & derivados , Técnicas de Inactivación de Genes , ARN Polimerasa II/metabolismo , ARN Bicatenario/metabolismo , Uracilo/metabolismoRESUMEN
The given investigation examined the neuroprotection role of 5-HT1b/1d agonist in reserpine induced Parkinson's disease (PD) in male Wistar rats. PD was induced in rats by reserpine at 5 mg/kg ip for 3 days and thereafter the rats were provided with the following treatments for 4 days, zolmitriptan (ZLM) group (30 mg/kg ip); STD group (levodopa + carbidopa, 200 + 5 mg/kg ip); ZLM + GA group (zolmitriptan, 30 mg/kg ip and glutamic acid, 1.5 mg/kg); ZLM + DX group (zolmitriptan, 30 mg/kg ip and dextromethorphan, 20 mg/kg ip). All the groups were then assessed for cognitive and motor functions at the end of the protocol. Moreover, oxidative stress parameters and histopathological changes were observed in rats of all treatment groups. Deposition of α-synuclein in the brain tissue was observed by silver staining. Data of this investigation revealed that motor and cognitive functions were improved in the ZLM-treated group compared with the negative control group, which was observed to be reversed in ZLM + GA group. Treatment with ZLM ameliorated oxidative stress and histopathological changes in the brain tissue of PD rats. Further, ZLM reduced the deposition of α-synuclein in PD rats, which reversed in ZLM + GA-treated group. This study concludes by stating that 5-HT1b/1d agonist can prevent neurodegeneration and reduce oxidative stress in PD rats. The probable underlying mechanism of such an effect of 5-HT1b/1d agonist could be by regulating the deposition of α-synuclein and reducing the expression of NMDA receptor.
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Oxazolidinonas , Enfermedad de Parkinson , Agonistas del Receptor de Serotonina 5-HT1 , Triptaminas , Masculino , Ratas , Animales , Agonistas del Receptor de Serotonina 5-HT1/farmacología , Enfermedad de Parkinson/tratamiento farmacológico , alfa-Sinucleína , Ácido Glutámico , Reserpina , Ratas WistarRESUMEN
KEY MESSAGE: An optimal RNAi configuration that could restrict gene expression most efficiently was determined. This approach was also used to target PTGS and yielded higher rates of gene-editing events. Although it was characterized long ago, transgene silencing still strongly impairs transgene overexpression, and thus is a major barrier to plant crop gene-editing. The development of strategies that could prevent transgene silencing is therefore essential to the success of gene editing assays. Transgene silencing occurs via the RNA silencing process, which regulates the expression of essential genes and protects the plant from viral infections. The RNA silencing machinery thereby controls central biological processes such as growth, development, genome integrity, and stress resistance. RNA silencing is typically induced by aberrant RNA, that may lack 5' or 3' processing, or may consist in double-stranded or hairpin RNA, and involves DICER and ARGONAUTE family proteins. In this study, RNAi inducing constructs were designed in eleven different configurations and were evaluated for their capacity to induce silencing in Nicotiana spp. using transient and stable transformation assays. Using reporter genes, it was found that the overexpression of a hairpin consisting of a forward tandem inverted repeat that started with an ATG and that was not followed downstream by a transcription terminator, could downregulate gene expression most potently. Furthermore, using this method, the downregulation of the NtSGS3 gene caused a significant increase in transgene expression both in transient and stable transformation assays. This SGS3 silencing approach was also employed in gene-editing assays and caused higher rates of gene-editing events. Taken together, these findings suggested the optimal genetic configuration to cause RNA silencing and showed that this strategy may be used to restrict PTGS during gene-editing experiments.
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Edición Génica , Silenciador del Gen , Plantas/genética , ARN , Interferencia de ARN , Transgenes/genéticaRESUMEN
Shammah is a traditional form of smokeless tobacco (ST) that is manufactured and used locally by people of Middle East with highest usage in Saudi Arabia, Yemen and Sudan. In Saudi Arabia, shammah comes in three variants: white, brown and yellow. In the present study, we investigated the genotoxicity of yellow shammah (YS) on bone marrow (BM) cells in vivo using mice. Bone marrow (BM) chromosomal aberration (CA) and micronucleus (MN) assay were performed and hepatic markers of oxidative stress were determined. Swiss albino mice were divided into five groups (n = 6) including negative control (NC) and positive control (PC) groups. The three treated groups included YS-100, 200 and 300 mg/kg, doses freshly prepared in 0.5% carboxymethyl cellulose (CMC) and administered orally once a day for 2 weeks. PC animals were administered cyclophosphamide (CP) at a dose of 40 mg/kg body weight, 24 h before termination. Two weeks continuous treatment of YS induced a dose dependent and significant increase in aberrant metaphases (AM), CA per cell and depression in mitotic activity. In micronucleus assay, YS treatment increased the percentage of micronucleated polychromatic erythrocytes (MNPCE) frequency and showed statistically significant reduction in polychromatic erythrocyte/normochromatic erythrocyte ratio at all doses, as compared to NC. YS also markedly inhibited the activities of superoxide dismutase, reduced glutathione and increased malondialdehyde content. CP was used as clastogen (positive control) and yielded the expected positive results. Therefore, it may be concluded that YS has genotoxic and cytotoxic effects for BM cells of mice in vivo.
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Células de la Médula Ósea/efectos de los fármacos , Aberraciones Cromosómicas/efectos de los fármacos , Tabaco sin Humo/toxicidad , Animales , Ciclofosfamida/toxicidad , Relación Dosis-Respuesta a Droga , Glutatión/metabolismo , Malondialdehído/metabolismo , Ratones , Pruebas de Micronúcleos/métodos , Medio Oriente , Pruebas de Mutagenicidad , Estrés Oxidativo/efectos de los fármacos , Superóxido Dismutasa/metabolismoRESUMEN
This study investigated both the mutagenicity and anti-mutagenicity of alpha-lipoic acid (ALA) in the bone marrow cells of mice using a chromosomal aberration assay. Cyclophosphamide (CP) 40 mg/kg was used as a clastogen in the positive control, and a vehicle-treated negative control group was also included. Multiple dose levels (15, 30, and 100 mg/kg of ALA) were given by intraperitoneal injection (IP) alone and in combination with CP (CP was administered 1 h prior to ALA). Bone marrow samples were collected 12 and 24 h after drug administration. The results demonstrated a significant increase in the frequency of chromosomal aberrations (CA) in bone marrow cells with depressions in the mitotic index (MI) of the positive control group of mice. However, in the groups of mice treated with different doses of ALA in the presence of CP, the percentages of CA decreased significantly with increases in mitotic activity. The results also indicate that ALA given alone in different doses had no mutagenic effect on mouse bone marrow cells. ALA has a dose and time-dependent protective effect against the mutagenicity induced by CP.
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Aberraciones Cromosómicas/efectos de los fármacos , Ciclofosfamida/antagonistas & inhibidores , Citoprotección , Ácido Tióctico/farmacología , Alquilantes/toxicidad , Animales , Células de la Médula Ósea/efectos de los fármacos , Aberraciones Cromosómicas/inducido químicamente , Ciclofosfamida/toxicidad , Masculino , Ratones , Índice Mitótico , Ácido Tióctico/toxicidadRESUMEN
This study was aimed to assess the genotoxicity of brown shammah (BS), a local form of smokeless tobacco, popular in Middle East countries including Yemen, Saudi Arabia and Sudan. The genotoxicity was explored using in vivo chromosomal aberration (CA), micronucleus (MN) and sperm abnormality (SA) assays. In addition, oxidative stress was also determined using various hepatic markers. Swiss albino mice were selected for the study, which were divided in to 5 groups of six animals each. They include, negative control (NC, received only vehicle) as well as positive control group (PC, received vehicle for 2 weeks followed by administration of cyclophosphamide, CP). Depending upon their dose, three BS treated animal groups were BS-100, 300 and 900 mg/kg. Doses of BS were obtained by suspending BS in 0.5% CMC (carboxy methyl cellulose) and orally administered once a day for 2 weeks. Significant augmentation of the average percentage of aberrant metaphase (AM), CA per cells and suppressed mitotic activity was observed on post administration of BS. In addition, BS increased the occurrence of MNPCEs (micronucleated polychromatic erythrocytes) formation, induced cytotoxicity and increased percentage of abnormal sperms as compared to NC. Moreover, BS also induced oxidative stress as the activities of hepatic superoxide dismutase (SOD) and glutathione (GSH) were reduced and malondialdehyde (MDA) content were increased by BS. Cyclophosphamide was utilized as clastogen, showed anticipated positive results and confirmed the sensitivity of test system. Therefore, it may be deduced from the study that the BS possesses genotoxic effects on mice bone marrow and germ cells in vivo.
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BACKGROUND: Denture hygiene is of utmost importance to maintain the dentures as well as the underlying tissues in appropriate health. Various denture cleansers as well as denture-based materials have evolved in the market; however, the effect of denture cleansers on different types of denture-based materials has not been very well documented. AIM: The purpose of this in vitro study was to evaluate and compare the surface roughness in heat-cured denture-based resin and injection-molded resin system as affected by two commercially available denture cleansers for a period of 15, 30, and 45 days. METHODOLOGY: A standardized metal die was fabricated to make 120 denture-based resin discs of uniform dimensions. The samples of heat-cured denture-based resin and injection-molded thermoplastic denture-based resin were immersed in the two denture cleansing solutions for a period of 15, 30, and 45 days, respectively. The surface roughness was evaluated by surface profilometer TR200. The data were subjected to statistical analysis and the comparison of quantitative data was done using unpaired t-test and repeated-measures ANOVA test. RESULTS: The surface roughness values (Ra) of heat cured denture base resin samples when immersed in two denture cleansers were 0.22 µm at 0 days, 0.27 and 0.29 µm at 15 days, 0.29 and 0.31 µm at 30 days, 0.30 and 0.31 µm at 45 days whereas for injection moulded samples surface roughness values were 1.31 & 1.27 µm at 0 days, 1.46 & 1.66 µm at 15 days, 1.50 & 1.69 µm at 30 days, and 1.50 & 1.69 µm at 45 days. CONCLUSION: The surface roughness (Ra) increased significantly in injection-molded polyamide denture-based resin samples when immersed in both the denture cleansers. Whereas, heat-cured denture-based resin samples did not reveal any significant surface changes at the various time intervals. Hence, the use of denture cleansers is questionable in thermoplastic resins.
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BACKGROUND: The medicinal legume Mucuna pruriens (L.) DC. has attracted attention worldwide as a source of the anti-Parkinson's drug L-Dopa. It is also a popular green manure cover crop that offers many agronomic benefits including high protein content, nitrogen fixation and soil nutrients. The plant currently lacks genomic resources and there is limited knowledge on gene expression, metabolic pathways, and genetics of secondary metabolite production. Here, we present transcriptomic resources for M. pruriens, including a de novo transcriptome assembly and annotation, as well as differential transcript expression analyses between root, leaf, and pod tissues. We also develop microsatellite markers and analyze genetic diversity and population structure within a set of Indian germplasm accessions. RESULTS: One-hundred ninety-one million two hundred thirty-three thousand two hundred forty-two bp cleaned reads were assembled into 67,561 transcripts with mean length of 626 bp and N50 of 987 bp. Assembled sequences were annotated using BLASTX against public databases with over 80% of transcripts annotated. We identified 7,493 simple sequence repeat (SSR) motifs, including 787 polymorphic repeats between the parents of a mapping population. 134 SSRs from expressed sequenced tags (ESTs) were screened against 23 M. pruriens accessions from India, with 52 EST-SSRs retained after quality control. Population structure analysis using a Bayesian framework implemented in fastSTRUCTURE showed nearly similar groupings as with distance-based (neighbor-joining) and principal component analyses, with most of the accessions clustering per geographical origins. Pair-wise comparison of transcript expression in leaves, roots and pods identified 4,387 differentially expressed transcripts with the highest number occurring between roots and leaves. Differentially expressed transcripts were enriched with transcription factors and transcripts annotated as belonging to secondary metabolite pathways. CONCLUSIONS: The M. pruriens transcriptomic resources generated in this study provide foundational resources for gene discovery and development of molecular markers. Polymorphic SSRs identified can be used for genetic diversity, marker-trait analyses, and development of functional markers for crop improvement. The results of differential expression studies can be used to investigate genes involved in L-Dopa synthesis and other key metabolic pathways in M. pruriens.
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Etiquetas de Secuencia Expresada/metabolismo , Perfilación de la Expresión Génica , Repeticiones de Microsatélite/genética , Anotación de Secuencia Molecular , Mucuna/genética , Minería de Datos , Polimorfismo Genético , ARN Mensajero/genética , Factores de Transcripción/genéticaRESUMEN
Photodynamic inactivation ofLeishmaniaspp. requires the cellular uptake of photosensitizers, e.g., endocytosis of silicon(IV)-phthalocyanines (PC) axially substituted with bulky ligands. We report here that when substituted with amino-containing ligands, the PCs (PC1 and PC2) were endocytosed and displayed improved potency againstLeishmania tropicapromastigotes and axenic amastigotesin vitro The uptake of these PCs by bothLeishmaniastages followed saturation kinetics, as expected. Sensitive assays were developed for assessing the photodynamic inactivation ofLeishmaniaspp. by rendering them fluorescent in two ways: transfecting promastigotes to express green fluorescent protein (GFP) and loading them with carboxyfluorescein succinimidyl ester (CFSE). PC-sensitizedLeishmania tropicastrains were seen microscopically to lose their motility, structural integrity, and GFP/CFSE fluorescence after exposure to red light (wavelength, â¼650 nm) at a fluence of 1 to 2 J cm(-2) Quantitative fluorescence assays based on the loss of GFP/CFSE from liveLeishmania tropicashowed that PC1 and PC2 dose dependently sensitized both stages for photoinactivation, consistent with the results of a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assay.Leishmania tropicastrains are >100 times more sensitive than their host cells or macrophages to PC1- and PC2-mediated photoinactivation, judging from the estimated 50% effective concentrations (EC50s) of these cells. Axial substitution of the PC with amino groups instead of other ligands appears to increase its leishmanial photolytic activity by up to 40-fold. PC1 and PC2 are thus potentially useful for photodynamic therapy of leishmaniasis and for oxidative photoinactivation ofLeishmaniaspp. for use as vaccines or vaccine carriers.
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Aminas/farmacología , Colorantes Fluorescentes/farmacología , Indoles/farmacología , Leishmania tropica/efectos de los fármacos , Estadios del Ciclo de Vida/efectos de los fármacos , Fármacos Fotosensibilizantes/farmacología , Aminas/síntesis química , Supervivencia Celular , Relación Dosis-Respuesta a Droga , Fluoresceínas/metabolismo , Colorantes Fluorescentes/síntesis química , Expresión Génica , Genes Reporteros , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Indoles/síntesis química , Concentración 50 Inhibidora , Isoindoles , Leishmania tropica/genética , Leishmania tropica/crecimiento & desarrollo , Leishmania tropica/metabolismo , Luz , Fotoquimioterapia , Fármacos Fotosensibilizantes/síntesis química , Relación Estructura-Actividad , Succinimidas/metabolismoRESUMEN
Asparagine is formed by two structurally distinct asparagine synthetases in prokaryotes. One is the ammonia-utilizing asparagine synthetase A (AsnA), and the other is asparagine synthetase B (AsnB) that uses glutamine or ammonia as a nitrogen source. In a previous investigation using sequence-based analysis, we had shown that Leishmania spp. possess asparagine-tRNA synthetase paralog asparagine synthetase A (LdASNA) that is ammonia-dependent. Here, we report the cloning, expression, and kinetic analysis of ASNA from Leishmania donovani. Interestingly, LdASNA was both ammonia- and glutamine-dependent. To study the physiological role of ASNA in Leishmania, gene deletion mutations were attempted via targeted gene replacement. Gene deletion of LdASNA showed a growth delay in mutants. However, chromosomal null mutants of LdASNA could not be obtained as the double transfectant mutants showed aneuploidy. These data suggest that LdASNA is essential for survival of the Leishmania parasite. LdASNA enzyme was recalcitrant toward crystallization so we instead crystallized and solved the atomic structure of its close homolog from Trypanosoma brucei (TbASNA) at 2.2 Å. A very significant conservation in active site residues is observed between TbASNA and Escherichia coli AsnA. It is evident that the absence of an LdASNA homolog from humans and its essentiality for the parasites make LdASNA a novel drug target.
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Aminoacil-ARNt Sintetasas/metabolismo , Aspartatoamoníaco Ligasa/metabolismo , Bacterias/enzimología , Leishmania donovani/enzimología , Secuencia de Aminoácidos , Aminoacil-ARNt Sintetasas/química , Aminoacil-ARNt Sintetasas/genética , Animales , Aspartatoamoníaco Ligasa/química , Aspartatoamoníaco Ligasa/genética , Secuencia de Bases , Cartilla de ADN , Microscopía Confocal , Modelos Moleculares , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Fracciones Subcelulares/enzimologíaRESUMEN
Recently, we reported molecular characterization, localization and functional importance of Arabino-1, 4-lactone oxidase (ALO) enzyme from Leishmania donovani that catalyses the last step in ascorbate biosynthesis pathway. Vitamin C (l-ascorbic acid) is implicated in several crucial physiological processes. To elucidate the biological role of d-arabinono-γ-lactone oxidase in Leishmania, we made L. donovaniâ ALO null mutant (ΔALO) by double targeted gene replacement. This mutant lacked ALO activity, showed transient growth defect and reduced ascorbate levels. ΔALO grown in ascorbate depleted media further enhanced growth defect with no detectable levels of ascorbate, implying that parasites have the ability to scavenge ascorbate. ΔALO mutants showed reduced survival in mouse macrophages and are impaired in their infectivity in vivo. Furthermore, the ΔALO mutant induced production of pro-inflammatory cytokines gamma interferon (IFN-gamma), interleukin-12 (IL-12) and tumour necrosis factor-α (TNF-α) by infected mouse macrophages. These mutants were susceptible to oxidative stresses in vitro as revealed by the decreased survival inside macrophages by increased production of reactive oxygen or nitrogen species. Complementation of the ΔALO mutants restored the phenotypic effects in these parasites. Our description of ALO null mutant parasite that triggers pro-inflammatory host responses provides a novel platform for targeting ALO in anti-parasitic strategies.
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Citocinas/metabolismo , Leishmania donovani/enzimología , Macrófagos/parasitología , Eliminación de Secuencia , Deshidrogenasas del Alcohol de Azúcar/metabolismo , Animales , Ácido Ascórbico/metabolismo , Línea Celular , Supervivencia Celular , Prueba de Complementación Genética , Leishmania donovani/genética , Leishmania donovani/fisiología , Ratones , Deshidrogenasas del Alcohol de Azúcar/genéticaRESUMEN
Genotoxicity of nimesulide (NM) was evaluated by employing bone marrow (BM) chromosomal aberration (CA) and micronucleus assays in Swiss albino mice. For BM CA assay, mice of either sex were treated orally with 1.5, 2.5 and 5 mg body weight solution of NM in 0.2 mL of 0.05% CMC (carboxy methyl cellulose) daily for 4, 13, 28 and 40 weeks. Treatment induced dose-dependent and significantly depressed mitotic activity and increase in CAs per cell in the BM cells after 13 weeks of treatment at all dose levels. In micronucleus assay, male mice were treated orally with the same dose levels and sampling durations as for CA assay. Treatment increased the percentage of micronucleated polychromatic erythrocytes frequency and showed a statistically significant reduction in polychromatic erythrocyte/normochromatic erythrocyte ratio, as compared to control groups. Cyclophosphamide (40 mg/kg) was used as clastogen (positive control) and yielded the expected positive results. Cytotoxicity was observed in the 8-week recovery period after 40 weeks of dosing, but it was not significant. On the basis of these findings, it may be concluded that in the long term, NM, or its biotransformed product, is genotoxic and cytotoxic for BM cells of mice in vivo.
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Antiinflamatorios no Esteroideos/toxicidad , Células de la Médula Ósea/efectos de los fármacos , Aberraciones Cromosómicas/inducido químicamente , Sulfonamidas/toxicidad , Administración Oral , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Células de la Médula Ósea/patología , Ciclofosfamida/toxicidad , Relación Dosis-Respuesta a Droga , Eritrocitos/efectos de los fármacos , Eritrocitos/patología , Femenino , Masculino , Ratones , Pruebas de Micronúcleos , Mutágenos/administración & dosificación , Mutágenos/toxicidad , Sulfonamidas/administración & dosificación , Factores de TiempoRESUMEN
INTRODUCTION: Colorectal cancer is a complex condition influenced by genetic mutations and environmental factors. Due to its intricate nature, the diagnosis and treatment of this condition require a comprehensive approach that considers individual circumstances. The study aimed to identify genes linked with colorectal cancer and their therapeutic agents from natural bioactive compounds. METHODS: The significantly prognostic differentially expressed genes (DEGs) were screened out from NCBI Gene Expression Omnibus (GEO) datasets. A protein-protein interaction network was constructed using STRING Database, and key genes were identified using Network Analyzer and CytoNCA plugins within Cytoscape. Further analysis involved functional annotations, and biological pathways analysis, SRC mechanism to uncover the role of SRC in CRC. Additionally, we performed virtual screening and molecular docking, Physiochemical property analysis along with MD simulation study to propose suitable natural compounds for promising therapeutic targets. RESULTS: The study conducted differential gene expression analysis, identifying 3621 statistically significant genes, with 1467 upregulated and 2154 downregulated. The top ten genes with the highest degree, betweenness centrality, and closeness centrality in the PPI network were selected as key genes. The SRC gene was found to have the highest degree and closeness centrality. Functional annotation and pathway analysis of key genes with a specific focus on the SRC mechanism revealed that the SRC's role in activating the RAS-RAF-MEK-ERK and Wnt/ß-catenin pathways in CRC cells, promoting proliferation and invasion. Molecular modelling of SRC led to the screening of phyto-compounds from tropical fruits, with Rutinexhibiting a higher docking score compared to FDA-approved anticancer drugs. MD simulations over 100 ns and the post-MD analysis i.e. RMSD, SASA, RMSF, FEL, RG, Hydrogen bond, PCA, and MMPBSA, comprehended the stable and robust interactions of a protein-ligand complex. These findings suggest Rutin's potential as a potent natural molecule for treating CRC. The study concludes that SRC plays a pivotal role in CRC, influencing cellular processes critical to cancer development and Rutin has been found to be a promising SRC inhibitor, suggesting a potential alternative therapeutic strategy for CRC. The consistent molecular interactions of Rutin necessitate further validation through wet lab experiments, offering hope for individuals affected by CRC.
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One of the major disturbing pathways within cancer is "The Kirsten rat sarcoma viral oncogene homolog (KRAS) pathway", and it has recently been demonstrated to be the most crucial in therapies and diagnostics. KRAS pathway includes numerous genes. This multi-component signaling system promotes cell growth, division, survival, and death by transferring signals from outside the cell to its interior. KRAS regulates the activation of a variety of signaling molecules. The KRAS oncogene is a key player in advancing a wide range of malignancies, and the mutation rank of this gene is a key feature of several tumors. For some malignancies, the mutation type of the gene may offer information about prognostic, clinical, and predictive. KRAS belongs to the RAS oncogene family, which consists of a compilation of minor GTP-binding proteins that assimilate environmental inputs and trigger internal signaling pathways that control survival, cell differentiation, and proliferation. This review aims to examine the recent and fascinating breakthroughs in the identification of new therapies that target KRAS, including the ever-expanding experimental approaches for reducing KRAS activity and signaling as well as direct targeting of KRAS. A literature survey was performed. All the relevant articles and patents related to the KRAS pathway, the mutation in the KRAS gene, cancer treatment, and diagnostics were found on PubMed and Google Patents. One of the most prevalent causes of cancer in humans is a mutation in the K-RAS protein. It is extremely difficult to decipher KRAS-mediated signaling. It allows transducing signals to go from the cell's outer surface to its nucleus, having an influence on a variety of crucial cellular functions including cell chemotaxis, division, dissemination, and cell death. Other involved signaling pathways are RAF, and the phosphatidylinositol 3 kinase also known as AKT. The EGFR pathway is incomplete without KRAS. The activation of PI3K significantly contributes to acquiring resistance to a mixture of MEK inhibitors and anti-EGFR in colorectal cancer cell lines which are mutated by KRAS. A series of recent patent studies towards cancer diagnostics and therapeutics reveals the paramount importance of mutated protein KRAS as an extensive driver in human tumors. For the prognosis, diagnosis, and treatment of colorectal cancer, KRAS plays a critical role. This review concludes the latest and vowing developments in the discovery of novel techniques for diagnosis and drugs that target KRAS, the advancements in experimental techniques for signaling and inhibiting KRAS function, and the direct targeting of KRAS for cancer therapeutics.
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Neoplasias Colorrectales , Genes ras , Humanos , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Patentes como Asunto , Neoplasias Colorrectales/tratamiento farmacológico , MutaciónRESUMEN
OBJECTIVE: In the present study, the effect of sildenafil on the pharmacokinetics of metformin was studied in experimental rats, and we also postulated the molecular mechanism by performing molecular docking studies. MATERIALS AND METHODS: Analysis of metformin and sildenafil (SIL) from rat plasma was done by high performance liquid chromatography. Optimum chromatographic separation and quantification of MET, SIL and Cetirizine was achieved on Phenomenex EVO C18 column with triethyl amine (0.3%): Methanol: Acetonitrile (70:05:25 v/v) as mobile phase maintaining flow rate of 1 ml/min, the detector was tuned at 224 nm. The extraction of MET and sildenafil from rat plasma was achieved by solid-phase extraction using Strata-X cartridges. The method was validated as per the ICH guidelines. For docking studies, the crystal structure of organic cation transporter 1 (OCT1) protein and multidrug and toxin extrusion (MATE) protein (5XJJ) were downloaded from the PubChem database. The docking study was performed by PyRx virtual screening software, and the results were analyzed by BIOVIA Discovery Studio. RESULTS: The validation of HPLC method was done, intraday and interday precision study of HPLC method demonstrated %RSD values less than 5%, the extraction recovery for MET and SIL were near to 80 % for low, medium and high QC samples. The plasma stability of MET and SIL showed % RSD values <10% for low, medium, and high QC samples. A sensitivity study for MET and SIL in rat plasma suggested a lower limit of quantification values of 8 and 10 ng/mL, respectively. The pharmacokinetic parameters were recorded, Cmax of experimental and control rats was 611.2 and 913.2 ng/mL; t1/2 1.66 and 1.98, AUC (0-t) 1637.5 and 2727.24, AUC (0-∞) 1832.38 and 2995.24 for MET. The results suggested that the Cmax of MET in experimental rats (MET + SIL) was 33.07% lower than the control (MET only) and also the t1/2 was 0.32 h shorter. Docking analysis suggested a higher binding affinity of sildenafil with MATE protein (5XJJ) compared to OCT1, suggesting possible involvement of MATE family proteins for pharmacokinetic alterations of MET. CONCLUSIONS: The HPLC and solid-phase extraction method were developed and applied successfully for the pharmacokinetics of MET and SIL. Intake of SIL altered the pharmacokinetics of MET in rats. Molecular docking studies suggested the involvement of MATE family proteins for alterations of MET pharmacokinetics.
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Metformina , Simulación del Acoplamiento Molecular , Citrato de Sildenafil , Animales , Citrato de Sildenafil/farmacocinética , Metformina/farmacocinética , Ratas , Masculino , Cromatografía Líquida de Alta Presión/métodos , Hipoglucemiantes/farmacocinética , Hipoglucemiantes/química , Interacciones Farmacológicas , Ratas WistarRESUMEN
Recently, 5-hydroxymethylcytosine (5hmC) was identified in mammalian genomic DNA. The biological role of this modification remains unclear; however, identifying the genomic location of this modified base will assist in elucidating its function. We describe a method for the rapid and inexpensive identification of genomic regions containing 5hmC. This method involves the selective glucosylation of 5hmC residues by the ß-glucosyltransferase from T4 bacteriophage creating ß-glucosyl-5-hydroxymethylcytosine (ß-glu-5hmC). The ß-glu-5hmC modification provides a target that can be efficiently and selectively pulled down by J-binding protein 1 coupled to magnetic beads. DNA that is precipitated is suitable for analysis by quantitative PCR, microarray or sequencing. Furthermore, we demonstrate that the J-binding protein 1 pull down assay identifies 5hmC at the promoters of developmentally regulated genes in human embryonic stem cells. The method described here will allow for a greater understanding of the temporal and spatial effects that 5hmC may have on epigenetic regulation at the single gene level.
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Citosina/análogos & derivados , ADN/química , Genómica/métodos , 5-Metilcitosina/análogos & derivados , Proteínas Portadoras , Citosina/análisis , Citosina/metabolismo , ADN/aislamiento & purificación , Células Madre Embrionarias/metabolismo , Regulación de la Expresión Génica , Genoma Humano , Glucosiltransferasas/metabolismo , Humanos , Regiones Promotoras Genéticas , Proteínas ProtozoariasRESUMEN
The present study investigated the protective effects of Foeniculum vulgare (fennel) essential oil (FEO) against genotoxicity induced by cyclophosphamide (CP). Mice bone marrow chromosomal aberration (CA), micronucleus, and sperm abnormality assays were employed to measure genotoxicity and cytotoxicity, respectively. The activities of superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), and malondialdehyde (MDA) content in the liver were also investigated spectrophotometrically. Animals were administered two different doses of FEO (1 and 2 mL/kg) continuously for 3 days at intervals of 24 hours by the oral route before tissue sampling. The results showed that CP produced a significant increase in the average percentage of aberrant metaphases and CAs, excluding gap and micronuclei formation in polychromatic erythrocytes (PCEs), produced cytotoxicity in mouse bone marrow cells, and induced abnormal sperms in the male germ line. CP also markedly inhibited the activities of SOD, CAT, and GSH and increased MDA content. Pretreatments with FEO significantly inhibited the frequencies of aberrant metaphases, CAs, micronuclei formation, and cytotoxicity in mouse bone marrow cells induced by CP and also produced a significant reduction of abnormal sperm and antagonized the reduction of CP-induced SOD, CAT, and GSH activities and inhibited increased MDA content in the liver. FEO inhibits genotoxicity and oxidative stress induced by CP.
Asunto(s)
Antimutagênicos/farmacología , Ciclofosfamida/toxicidad , Foeniculum/química , Aceites Volátiles/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/ultraestructura , Catalasa/metabolismo , Aberraciones Cromosómicas , Masculino , Ratones , Micronúcleos con Defecto Cromosómico , Espermatozoides/efectos de los fármacos , Superóxido Dismutasa/metabolismoRESUMEN
The present study investigated the protective effects of Syzygium cumini extract (SCE; 100 and 200 mg/kg) against genotoxicity and oxidative stress (OS) induced by cyclophosphamide (CP) in mice. Animals were received 14 days pretreatment (oral) of SCE, followed by induction of genotoxicity by CP (40 mg/kg), 24 hours before sacrifice. Mice bone marrow chromosomal aberration assay, micronucleus assay, and sperm abnormality assay were employed for the study. Activities of hepatic antioxidant enzymes were also investigated. Phytochemical investigation was done to determine total phenolic and flavonoid content in SCE. Results showed that CP produced a significant increase in average percentage of aberrant metaphases and chromosomal aberrations (CAs) excluding gap, and micronuclei (MN) formation in polychromatic erythrocytes produced cytotoxicity in mouse bone marrow cells and induced abnormal sperms in a male germ line. CP also markedly inhibited the activities of superoxide dismutase (SOD), catalase (CAT), and reduced glutahione (GSH) and increased malondialdehyde (MDA) content. Pretreatments with SCE significantly inhibited the frequencies of aberrant metaphases, CAs, MN formation, and cytotoxicity in mouse bone marrow cells induced by CP. SCE also produced a significant reduction of abnormal sperm and antagonized the reduction of CP-induced SOD, CAT, and GSH activities and inhibited increased MDA content in the liver. Total phenolic content present in SCE was 24.68%, whereas total flavonoids were calculated as 3.80%. SCE has a protective effect against genotoxicity and OS induced by CP.
Asunto(s)
Extractos Vegetales/análisis , Extractos Vegetales/farmacología , Syzygium/química , Análisis de Varianza , Animales , Células de la Médula Ósea/efectos de los fármacos , Catalasa/metabolismo , Aberraciones Cromosómicas/inducido químicamente , Ciclofosfamida/toxicidad , Daño del ADN/efectos de los fármacos , Flavonoides/metabolismo , Glutatión/metabolismo , Masculino , Malondialdehído/metabolismo , Ratones , Pruebas de Micronúcleos , Estrés Oxidativo/efectos de los fármacos , Fenoles/metabolismo , Espermatozoides/anomalías , Espermatozoides/efectos de los fármacos , Superóxido Dismutasa/metabolismoRESUMEN
BACKGROUND: Colorectal cancer is estimated to become the leading cause of cancer death worldwide. Since most of the available therapies affect vital organs such as heart and liver, herbal remedies as a substitute therapy have been reported in several evidence-based studies. OBJECTIVE: Medicinal plants exhibit a diverse range of bioactive elements known for their medicinal properties, such as anti-inflammatory, anticancer, antioxidant, and antimicrobial effects. Phytochemicals present in medicinal plants significantly trigger different signaling pathways, contributing to their therapeutic activities. This review covers a comprehensive summary of the therapeutic potential of an herbal diet in treating colorectal cancer and other ailments. Special attention will be given to exploring the interactions of medicinal plants with the microbiota and their associations with cancer pathways. CONCLUSION: A medicinal plant rich in bioactive compounds is a therapeutic option for colorectal cancer and potent cardioprotective and hepatoprotective agents. These bioactive compounds have demonstrated the ability to impede the growth of cancerous cells and trigger apoptosis. Our findings suggest that pomegranate, garlic, soybean, olive, green tea, papaya, and grapes are potential medicinal plants for combating cancer and related side effects. Bioactive compounds can modulate the gut microbiota's metabolism, and short-chain fatty acid production shows cardioprotective effects and reduces the risk of colorectal cancer. Hence, it can be stated that the interaction between a medicinal plant-rich diet and the gut microbiota plays a crucial role in preventing colorectal cancer and cardiac arrest.
RESUMEN
Irrespective of men and women, colorectal cancer (CRC), is the third most common cancer in the population with more than 1.85 million cases annually. Fewer than 20% of patients only survive beyond five years from diagnosis. CRC is a highly preventable disease if diagnosed at the early stage of malignancy. Several screening methods like endoscopy (like colonoscopy; gold standard), imaging examination [computed tomographic colonography (CTC)], guaiac-based fecal occult blood (gFOBT), immunochemical test from faeces, and stool DNA test are available with different levels of sensitivity and specificity. The available screening methods are associated with certain drawbacks like invasiveness, cost, or sensitivity. In recent years, computer-aided systems-based screening, diagnosis, and treatment have been very promising in the early-stage detection and diagnosis of CRC cases. Artificial intelligence (AI) is an enormously in-demand, cost-effective technology, that uses various tools machine learning (ML), and deep learning (DL) to screen, diagnose, and stage, and has great potential to treat CRC. Moreover, different ML algorithms and neural networks [artificial neural network (ANN), k-nearest neighbors (KNN), and support vector machines (SVMs)] have been deployed to predict precise and personalized treatment options. This review examines and summarizes different ML and DL models used for therapeutic intervention in CRC cancer along with the gap and challenges for AI.