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Hematopoietic syndrome contributes to mortality after exposure to high doses of low LET radiation. In this context, we have earlier demonstrated the potential of G-003 M (a combination of podophyllotoxin and rutin) in alleviating radiation-induced bone marrow suppression. Similarly, we here demonstrate that G-003 M protected mice from death (>83% protection) and increased the populations of CD 34 (Cluster of differentiation 34) as well as CD 117 (Cluster of differentiation 117) positive cell population and their colony forming capacity. This was accompanied with increase in the serum titre of granulocyte colony stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor (GM-CSF). Interestingly, G-003 M lowered down the titre of fms-like tyrosine kinase (Flt-3) ligands. Our results furthermore demonstrates that G-003 M facilitated the nuclear translocation of ß-catenin and upregulated the expression of Wnt 10b. Conditioning of animal with G-003 M activated the expression of survivin, inhibited the activation of Caspase-3 in CD 34/117+ progenitor stem cells and protected the bone marrow vascularity and splenic colonies in lethally irradiated animals, which collectively promoted hemopoietic recovery in lethally irradiated mice.
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Rayos gamma , Hematopoyesis/efectos de los fármacos , Hematopoyesis/efectos de la radiación , Podofilotoxina/farmacología , Rutina/farmacología , Animales , Apoptosis/efectos de los fármacos , Médula Ósea/efectos de los fármacos , Médula Ósea/efectos de la radiación , Proliferación Celular/efectos de los fármacos , Quimioterapia Combinada , Femenino , Células Madre Hematopoyéticas/metabolismo , Ratones Endogámicos C57BL , Podofilotoxina/administración & dosificación , Rutina/administración & dosificación , Regulación hacia Arriba/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacosRESUMEN
Wound inflammation is a rapid and highly orchestrated process that significantly impacts the wound healing cascade. Consequent to injury, a series of events set off that include inflammatory, proliferation and maturation phases leading to wound closure and restoration of normal skin integrity. Stimuli causing stress to host immune system or induce inflammatory response include tissue damage and pathogenic microbial infection.Several evidences points towards the positive role of inflammation as it essential to fight against the attack of invading pathogens and to remove dead tissues from the site of injury. Besides its positive role, prolonged inflammation is injurious and may result in deregulated stages of the wound healing which may lead to excessive scarring. Achieving balance in inflammatory cascade is one of the challenging tasks for development of a wound healing drug. This review mainly focuses on the pharmacological control of inflammation by agents which critically balance the inflammatory cascade. However, none of the agent is available in the healthcare market which exclusively plays a role in wound repair. In this review we shall explore different factors or agents affecting inflammation in wound healing. This information might be helpful in designing and development new process, technologies or drugs for better management of wound care. In addition, understanding the effect of inflammation on the outcome of the healing process will serve as a significant milestone in the area of pathological tissue repair.
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Inflamación/tratamiento farmacológico , Cicatrización de Heridas/efectos de los fármacos , Administración Tópica , Antiinflamatorios no Esteroideos/normas , Antiinflamatorios no Esteroideos/uso terapéutico , Inhibidores de la Ciclooxigenasa/normas , Inhibidores de la Ciclooxigenasa/uso terapéutico , Colorantes Fluorescentes/normas , Colorantes Fluorescentes/uso terapéutico , Humanos , Inflamación/prevención & control , Insulina/administración & dosificación , Insulina/normas , Insulina/uso terapéutico , Células Madre Mesenquimatosas , MicroARNs/normas , MicroARNs/uso terapéuticoRESUMEN
BACKGROUND: Pulmonary hypertension (PH) is the abnormal elevation of pressure in the pulmonary vascular system, with various underlying causes. A specific type of PH is pulmonary arterial hypertension (PAH), a severe condition characterized by high pulmonary arterial pressure resulting from structural changes in distal pulmonary vessels, altered arterial tone, and inflammation. This leads to right ventricular hypertrophy and heart failure. The molecular mechanisms behind PAH are not well understood. This manuscript aims to elucidate these mechanisms using the genetic tool, aiding in diagnosis and treatment selection. METHOD: In our present study, we have obtained blood samples from both patients with pulmonary arterial hypertension (PAH) and healthy individuals. We conducted a comparative transcriptome analysis to identify genes that are either upregulated or downregulated in PAH patients when compared to the control group. Subsequently, we carried out a validation study focusing on the log2-fold downregulated genes in PAH, employing Quantitative Real-Time PCR for confirmation. Additionally, we quantified the proteins encoded by the validated genes using the ELISA technique. RESULTS: The results of the transcriptome analysis revealed that 97 genes were significantly upregulated, and 6 genes were significantly downregulated. Among these, we chose to focus on and validate only four of the downregulated genes, as they were directly or indirectly associated with the hypertension pathway. We also conducted validation studies for the proteins encoded by these genes, and the results were consistent with those obtained in the transcriptome analysis. CONCLUSION: In conclusion, the findings of this study indicate that the four validated genes identified in the context of PAH can be further explored as potential targets for both diagnostic and therapeutic applications.
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Regulación hacia Abajo , Perfilación de la Expresión Génica , Hipertensión Arterial Pulmonar , Humanos , Femenino , Masculino , Hipertensión Arterial Pulmonar/genética , Hipertensión Arterial Pulmonar/fisiopatología , India , Persona de Mediana Edad , Adulto , Transcriptoma , Regulación hacia Arriba , Hipertensión Pulmonar/genética , Hipertensión Pulmonar/fisiopatología , Estudios de Casos y ControlesRESUMEN
The 2022 Monkeypox virus, an evolved DNA strain originating in Africa, exhibits heightened human-to-human transmissibility and potential animal transmission. Its host remains unidentified. While its initial slow transmission rate restrained global impact, 2022 saw a surge in cases, causing widespread concern in over 103 countries by September. This virus's distinctive human-to-human transmission marks a crucial shift, demanding a prompt revaluation of containment strategies. However, the host source for this shift requires urgent research attention. Regrettably, no universal preventive or curative methods have emerged for this evolved virus. Repurposed from smallpox vaccines, only some vaccinations offer a partial defense. Solely one therapeutic drug is available. The article's essence is to provide a comprehensive grasp of the virus's epidemiology, morphology, immune invasion mechanisms, and existing preventive and treatment measures. This knowledge equips researchers to devise strategies against its spread and potential public health implications.
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Mpox , Aceites Volátiles , Animales , Humanos , Mpox/epidemiología , Mpox/prevención & control , Brotes de Enfermedades/prevención & control , Salud Pública , ÁfricaRESUMEN
Background: The World Health Organization declared the coronavirus disease 2019 (COVID-19) a global pandemic on 11 March 2020. Identifying the infected people and isolating them was the only measure that was available to control the viral spread, as there were no standardized treatment interventions available. Various public health measures, including vaccination, have been implemented to control the spread of the virus worldwide. India, being a densely populated country, required laboratories in different zones of the country with the capacity to test a large number of samples and report test results at the earliest. The Indian Council of Medical Research (ICMR) took the lead role in developing policies, generating advisories, formulating guidelines, and establishing and approving testing centers for COVID-19 testing. With advisories of ICMR, the National Institute of Cancer Prevention and Research (NICPR) established a high-throughput viral diagnostic laboratory (HTVDL) for RT-PCR-based diagnosis of SARS-CoV-2 in April 2020. HTVDL was established during the first lockdown to serve the nation in developing and adopting rapid testing procedures and to expand the testing capacity using "Real-Time PCR." The HTVDL provided its testing support to the national capital territory of Delhi and western Uttar Pradesh, with a testing capacity of 6000 tests per day. The experience of establishing a high-throughput laboratory with all standard operating procedures against varied challenges in a developing country such as India is explained in the current manuscript which will be useful globally to enhance the knowledge on establishing an HTVDL in pandemic or non-pandemic times.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Prueba de COVID-19 , Laboratorios , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Control de Enfermedades TransmisiblesRESUMEN
Monitoring graft health and detecting graft rejection is crucial for the success of post-transplantation outcomes. In Western countries, the use of donor-derived cell-free DNA (dd-cfDNA) has gained widespread recognition as a diagnostic tool for kidney transplant recipients. However, the role of dd-cfDNA among the Indian population remains unexplored. The recipients were categorized into two groups: the post-transplant recipient (PTR) group (n = 16) and the random recipient (RR) group (n = 87). Blood samples were collected daily from the PTR group over a 7-day period, whereas the RR group's samples were obtained at varying intervals. In this study, we used a targeted approach to identify dd-cfDNA, which eliminated the need for genotyping, and is based on the minor allele frequency of SNP assays. In the PTR group, elevated dd-cfDNA% levels were observed immediately after transplantation, but returned to normal levels within five days. Within the RR group, heightened serum creatinine levels were directly proportional to increased dd-cfDNA%. Sixteen recipients were advised to undergo biopsy due to elevated serum creatinine and other pathological markers. Among these sixteen recipients, six experienced antibody-mediated rejection (ABMR), two exhibited graft dysfunctions, two had active graft injury, and six (37.5%) recipients showed no rejection (NR). In cases of biopsy-proven ABMR and NR, recipients displayed a mean ± SD dd-cfDNA% of 2.80 ± 1.77 and 0.30 ± 0.35, respectively. This study found that the selected SNP assays exhibit a high proficiency in identifying donor DNA. This study also supports the use of dd-cfDNA as a routine diagnostic test for kidney transplant recipients, along with biopsies and serum creatinine, to attain better graft monitoring.
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BACKGROUND: Sulfur Mustard is a strong vesicant and chemical warfare agent that imposes toxicity to the lungs, eyes, and skin after accidental or intended exposure. OBJECTIVES: The current study was intended to explore in vitro and in vivo decontamination properties of electrolytically generated HOCl (hypochlorous acid) against CEES (2-chloroethyle ethyle sulphide), a known sulfur mustard simulant & vesicating agent. METHODS: in vitro studies were carried out using UV spectroscopy and GC-MS methods. In vivo studies were performed in Strain A and immune-compromised mice by subcutaneous as well as prophylactic topical administration of HOCl pretreated CEES. The blister formation and mortality were considered as end-point. Histopathological study was conducted on skin samples by H & E method. DNA damage studies measuring γ-H2AX and ATM have been carried out in human blood using flow cytometry. Anti-bacterial action was tested by employing broth micro dilution methods. A comparative study was also carried out with known oxidizing agents. RESULTS: The topical application of pre-treated CEES at 5, 30 min and 1 h time points showed significant (p<0.001) inhibition of blister formation. DNA damage study showed reduced mean fluorescence intensity of DSBs nearly 17-20 times, suggesting that HOCl plays a protective role against DNA damage. Histopathology showed no sign of necrosis in the epidermis upto 5 min although moderate changes were observed at 30 min. Pretreated samples were analyzed for detection of reaction products with m/z value of 75.04, 69.08, 83.93, 85.95, 123.99, 126.00, and 108.97. HOCl showed a strong bactericidal effect at 40 ppm. The absorbance spectra of HOCl treated CEES showed lowered peaks in comparison to CEES alone and other oxidizing agents. CONCLUSION: In a nutshell, our results signify the decontamination role of HOCl for biological surface application.
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Sustancias para la Guerra Química , Gas Mostaza , Animales , Sustancias para la Guerra Química/farmacología , Descontaminación , Ácido Hipocloroso/farmacología , Ratones , Gas Mostaza/farmacología , PielRESUMEN
Gliomas are the most prevalent kind of malignant and severe brain cancer. Apoptosis regulating mechanisms are disturbed in malignant gliomas, as they are in added forms of malignancy. Understanding apoptosis and other associated processes are thought to be critical for understanding the origins of malignant tumors and designing anti-cancerous drugs for the treatment. The purpose of this study was to evaluate the variation in the expression level of several apoptotic proteins that are responsible for apoptosis in low to high-grade glioma. This suggests a significant change in the expression of five apoptotic proteins: Clusterin, HSP27, Catalase, Cytochrome C, and SMAC. Cytochrome C, one of the five substantially altered proteins, is a crucial component of the apoptotic cascade. The complex enzyme Cytochrome C is involved in metabolic pathways such as respiration and cell death. The results demonstrated that Cytochrome C expression levels are lower in glioma tissues than in normal tissues. What's more intriguing is that the expression level decreases with an increase in glioma grades. As a result, the discovery shows that Cytochrome C may be a target for glioma prognostic biomarkers.
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Current models to study the hematopoietic syndrome largely rely on the uniform whole-body exposures. However, in the radio-nuclear accidents or terrorist events, exposure can be non-uniform. The data available on the non-uniform exposures is limited. Thus, we have developed a mice model for studying the hematopoietic syndrome in the non-uniform or partial body exposure scenarios using the localized cobalt60 gamma radiation exposure. Femur region of Strain 'A' male mice was exposed to doses ranging from 7 to 20 Gy. The 30 day survival assay showed 19 Gy as LD100 and 17 Gy as LD50. We measured an array of cytokines and important stem cell markers such as IFN-γ, IL-3, IL-6, GM-CSF, TNF-α, G-CSF, IL-1α, IL-1ß, CD 34 and Sca 1. We found significant changes in IL-6, GM-CSF, TNF-α, G-CSF, and IL-1ß levels compared to untreated groups and amplified levels of CD 34 and Sca 1 positive population in the irradiated mice compared to the untreated controls. Overall, we have developed a mouse model of the hematopoietic acute radiation syndrome that might be useful for understanding of the non-uniform body exposure scenarios. This may also be helpful in the screening of drugs intended for individuals suffering from radiation induced hematopoietic syndrome.
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Síndrome de Radiación Aguda/etiología , Modelos Animales de Enfermedad , Enfermedades Hematológicas/etiología , Exposición a la Radiación/efectos adversos , Síndrome de Radiación Aguda/genética , Síndrome de Radiación Aguda/metabolismo , Animales , Radioisótopos de Cobalto/efectos adversos , Radioisótopos de Cobalto/química , Citocinas/genética , Citocinas/metabolismo , Fémur/metabolismo , Fémur/efectos de la radiación , Rayos gamma/efectos adversos , Enfermedades Hematológicas/genética , Enfermedades Hematológicas/metabolismo , Humanos , Masculino , RatonesRESUMEN
BACKGROUND: The currently available practices for creation of burns in the animals are mostly manual which may lead to lack of uniform wound. There is a need to develop a suitable device that could reproduce and uniformly create burn wound in animal models without the procedural variations and human variability. Present study deals with development of a burn device which has been designed for creation of animal models for burn injury. METHODS: The designed burn device comprises of two main components a heating metal stylus and the thermal sensor. Metal stylus consists of two parts with top part acts as handle and bottom part contains the aluminum probe which quickly heats and cool. The temperature monitoring sensor is attached adjacent to the tip of the probe. The temperature and timer are digitally displayed and can be adjusted as per the requirement. This device is tested for creation of uniform burn in the mice model. Animals were divided into different groups and thermal burn was generated for 60 °C, 80 °C & 100 °C respectively. Burn wound was generated dorsally on shaved skin with contact time of 40 s. Skin biopsies of burn wound were collected after 24 h for histopathology analysis to determine the burn characteristics. Blood vessels damage in the skin was detected by transillumination and digital segmentation using VesSeg tool. RESULTS: The device is able to deliver the different temperature to the animal skin. After reaching the 60 °C, 80 °C & 100 °C for 40 s respectively electronic relays shut down the device. The different groups of the animals showed significant difference in burn morphology in temperature dependent manner. Non significant variation in the burn area of different experimental groups animals was observed. All three zones vis-a-vis coagulation, stasis and hyperaemia were observed at 100 °C whereas found indistinct in 80 °C and 60 °C treated groups. Histopathological studies clearly demonstrated the differences in damage induction in stratum corneum, epidermis, dermis, collagen and hair follicle at selected thermal points. Severe blood vessels damage was observed only at 100 °C. The vascular perfusion was recorded 14% and 57% higher in 60 °C and 80 °C treated animals respectively when compared to control animals. However, at 100 °C due to highest vessel damage the perfusion was reduced to 53% compared to control. CONCLUSION: Present study demonstrates that the device is able to generate precise and uniform burn wound in mice model. The device may be useful for burn related studies and validation of burn wound care products.
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Quemaduras/patología , Diseño de Equipo , Calor , Piel/patología , Animales , Modelos Animales de Enfermedad , Ratones , Piel/irrigación sanguíneaRESUMEN
The present study is aimed to investigate the radioprotective efficacy of G-003M (combination of podophyllotoxin and rutin) against gamma radiation-induced oxidative stress and subsequent cell death in mice bone marrow and spleen. Prophylactic administration of G-003M (-1 h) rendered more than 85% survival in mice exposed to 9 Gy (lethal dose) with dose reduction factor of 1.26. G-003M pretreated mice demonstrated significantly reduced level of reactive oxygen species, membrane lipid peroxidation, and retained glutathione level. In the same group, we obtained increased expression of master redox regulator, nuclear factor erythroid-derived like-2 factor (Nrf-2), and its downstream targets (heme oxygenase-1, Nqo-1, glutathione S-transferase, and thioredoxin reductase-1). In addition, G-003M preadministration has also shown a significant reduction in Keap-1 level (Nrf-2 inhibitor). Radiation-induced lethality was significantly amended in combination-treated (G-003M) mice as demonstrated by reduced 8-OHdG, annexin V FITC+ cells, and restored mitochondrial membrane potential. Expression of antiapoptotic protein Bcl-2 and Bcl-xL was restored in G-003M pretreated group. However, proapoptotic proteins (Puma, Bax, Bak, Caspase-3, and Caspase-7) were significantly declined in this group. Further analysis of immune cells revealed G-003M-mediated restoration of CD3 and CD19 receptor, which was found decreased to significant level following irradiation. Similarly, Gr-1, a marker of granulocytes, was also retained by G-003M administration prior to radiation. Modulatory potential of this formulation (G-003M) can be exploited as a safe and effective countermeasure against radiation-induced lymphohemopoietic injury.
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Drug discovery field has tremendously progressed during last few decades, however, an effective radiation countermeasure agent for the safe administration to the victims of radiation exposure is still unavailable. This multi-model study is aimed at elucidating the mechanistic aspects of a novel podophyllotoxin and rutin combination (henceforth referred as G-003M) in the hematopoietic radioprotection and its involvement in the DNA damage and repair signaling pathways. Using in silico study, we identified the binding sites and structural components of G-003M and validated in vitro. We further studied various in vivo endpoints related to the DNA repair and cell death pathways in mice pre-administered with G-003M, irradiated and subsequently euthanized to collect blood and bone marrow cells. In silico study showed the binding of podophyllotoxin to ß-tubulin and presence of a functional hydroxyl group in the rutin, suggested their involvement in G2/M arrest and the free radical scavenging respectively. This experimentation was further validated through in vitro studies. In vivo mice studies confirmed that G-003M pre-administration attenuated DNA damage and enhanced repair after whole body exposure. We further noticed a decrease in the levels of γH2AX, p53BP1, and ATM kinase and an increase in the levels of DNA pk, Ku 80, Ligase IV, Mre 11, Rad 50 and NBS 1 in the blood and bone marrow cells of the G-003M pre-administered and irradiated mice. We noticed an overall increase in the pro-survival factors in the G-003M pre-treated and irradiated groups establishing the radioprotective efficacy of this formulation. The lead obtained from this study will certainly help in developing this formulation as a safe and effective radioprotector which could be used for humans against any planned or emergency exposure of radiation.
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Development of an effective radio protector to minimise radiation-inflicted damages have largely failed owing to inherent toxicity of most of the agents examined so far. This study is centred towards delivering protection to lethally irradiated mice by pre-administration of a safe formulation G-003M (combination of podophyllotoxin and rutin) majorly through regulation of inflammatory and cell death pathways in mice. Single intramuscular dose of G-003M injected 60 min prior to 9 Gy exposure rescued 89% of whole body lethally irradiated C57BL/6J mice. Studies have revealed reduction in radiation induced reactive oxygen species (ROS), nitric oxide (NO) generation, prostaglandin E2 (PGE2) levels and intestinal apoptosis in G-003M pre-treated mice intestine. Restricted nuclear translocation of redox-sensitive Nuclear factor-κB (NF-κB) and subsequent downregulation of cyclo-oxygenase 2 (COX-2), inducible nitric oxide synthase (iNOS; EC 1.14.13.39) and tumor necrosis factor (TNF-α) levels demonstrated the anti-inflammatory effect that G-003M exerts. Support to early hematopoietic recovery was exhibited through G-003M mediated induction of granulocyte colony stimulating factor (G-CSF) and interleukin (IL-6) levels in lethally irradiated mice. Considerable attenuation in radiation induced morphological damage to the intestinal villi, crypts and mucosal layers was observed in G-003M pre-treated mice. Additionally, our formulation did not reduce the sensitivity of tumor tissue to radiation. Altogether, these results suggest that G-003M ameliorates the deleterious effects of radiation exposure by minimising ROS and NO generation and effectively regulating inflammatory and cell death pathways. Mechanism of protection elucidated in the current study demonstrates that G-003M can be used as a safe and effective radio protective agent in radiotherapy for human application.
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Tracto Gastrointestinal/efectos de los fármacos , Podofilotoxina/farmacología , Traumatismos por Radiación/tratamiento farmacológico , Traumatismos por Radiación/metabolismo , Rutina/farmacología , Transducción de Señal/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Animales , Ciclooxigenasa 2/metabolismo , Dinoprostona/metabolismo , Quimioterapia Combinada/métodos , Tracto Gastrointestinal/efectos de la radiación , Hemo-Oxigenasa 1/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2/metabolismo , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Protectores contra Radiación , Especies Reactivas de Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
The present study was conceptualized with the aim of developing a safe radioprotector for human application against radiation induced toxicity. For this study, a formulation (G-002M) prepared by combining three active principles isolated from rhizomes of Podophyllum hexandrum, was evaluated for its potential to protect genomic DNA of human blood cells exposed to different doses of radiation (5,7&10Gy). Blood samples were pretreated (-1hr to exposure) with G-002M. Parameters of Premature Chromosome Condensation (PCC) assay like PCC-index, PCC-rings and PCC-fragments were used to estimate radiation induced chromosomal aberrations. Radiation (7Gy) induce ROS generation and its modulation by G-002M was determined by flow-cytometry and fluorescent microscopy while apoptosis (0,2,24&48 hr) was analyzed using TUNEL assay. Effect on spindle organization in G2/M arrested cells by all the three compounds individually was studied using immunofluorescence microscopy. Irradiation caused dose dependent linear increase in PCC-rings and fragments, while decline in PCC index. G-002M pretreatment significantly decreased these chromosomal aberrations at all the radiation doses and assisted cell survival as indicated by increased PCC index compared with radiation only group. Significant decrease in radiation induced intracellular ROS (45 ± 3%) and apoptosis (49.9%) was also exhibited by the formulation. On podophyllotoxin treatment, most of the cells have shown blocked spindles however, depicted normal arrangement. G-002M also demonstrated a highly significant Dose Modifying Factor or DMF (PCC-rings: 2.27 and PCC-fragments: 1.60). Present study based on many parameters along with DMF study, strongly suggests that G-002M is an effective formulation with a potential to minimize chromosomal damage even at very high radiation doses.
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Apoptosis , Aberraciones Cromosómicas , Glucósidos/química , Linfocitos/efectos de los fármacos , Podofilotoxina/farmacología , Especies Reactivas de Oxígeno/metabolismo , Rutina/farmacología , Humanos , Linfocitos/metabolismo , Podofilotoxina/química , Dosis de RadiaciónRESUMEN
DNA damage can be assessed by the quantitation of γH2AX foci that form at DSB sites. This study examines the generation and persistence of γH2AX foci, variability in foci size after acute and fractionated radiation exposure, and the effect of pretreatment with a safe radioprotective formulation termed G-003M on foci generation and persistence. G-003M contains a combination of podophyllotoxin and rutin hydrate, and was administered intramuscularly to rabbits 1 hr prior to Co(60) gamma irradiation. Rabbits were assigned to one of the following treatment groups: untreated, G-003M alone, irradiated (single dose 8 Gy, fractionated 2 Gy/day for 4 days or single dose 2 Gy) or G-003M preadministration followed by radiation exposure. Foci continuously persisted for a week in peripheral blood mononuclear cells of rabbits exposed to a single 8 Gy dose. However, the number of foci gradually decreased after reaching a maximum at 1 h. In rabbits exposed to fractionated radiation, foci detected 1 hr after the final exposure were significantly larger (P < 0.001) than in rabbits exposed to a single 8 Gy dose, but disappeared completely after 24 h. In both groups, foci reappeared on days 11-15 in terminally ill animals. G-003M pretreatment significantly (P < 0.05) attenuated the formation of γH2AX foci in all irradiated rabbits. This study reveals that γH2AX focus assessment could be used to confirm radiation exposure, that focus size reflects the type of radiation exposure (acute or fractionated), that the re-appearance of foci is a strong indicator of imminent death in animals, and that G-003M provides protection against radiation. Environ. Mol. Mutagen. 57:455-468, 2016. © 2016 Wiley Periodicals, Inc.
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Rayos gamma/efectos adversos , Sitios Genéticos , Histonas/metabolismo , Leucocitos Mononucleares/efectos de la radiación , Podofilotoxina/farmacología , Protectores contra Radiación/farmacología , Rutina/farmacología , Animales , Roturas del ADN de Doble Cadena/efectos de los fármacos , Roturas del ADN de Doble Cadena/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Sinergismo Farmacológico , Citometría de Flujo , Histonas/genética , Cinética , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Masculino , Podofilotoxina/administración & dosificación , Conejos , Dosis de Radiación , Protectores contra Radiación/administración & dosificación , Rutina/administración & dosificación , Irradiación Corporal TotalRESUMEN
Radiation exposure is a serious threat to biomolecules, particularly DNA, proteins and lipids. Various exogenous substances have been reported to protect these biomolecules. In this study we explored the effect of pre-treatment with G-002M, a mixture of three active derivatives isolated from the rhizomes of Podophyllum hexandrum, on DNA damage response in irradiated human blood leukocytes. Blood was collected from healthy male volunteers, preincubated with G-002M and then irradiated with various doses of radiation. Samples were analyzed using flow cytometry to quantify DNA double strand break (DSB) biomarkers including γ-H2AX, P53BP1 and levels of ligase IV. Blood samples were irradiated in vitro and processed to determine time and dose-dependent kinetics. Semiquantitative RT-PCR was performed at various time points to measure gene expression of DNA-PKcs, Ku80, ATM, and 53BP1; each of these genes is involved in DNA repair signaling. Pre-treatment of blood with G-002M resulted in reduction of γ-H2AX and P53BP1 biomarkers levels and elevated ligase IV levels relative to non-G-002M-treated irradiated cells. These results confirm suppression in radiation-induced DNA DSBs. Samples pre-treated with G-002M and then irradiated also showed significant up-regulation of DNA-PKcs and Ku80 and downregulation of ATM and 53BP1 gene expressions, suggesting that G-002M plays a protective role against DNA damage. The protective effect of G-002M may be due to its ability to scavange radiation-induced free radicals or assist in DNA repair. Further studies are needed to decipher the role of G-002M on signaling molecules involved in radiation-induced DNA damage repair pathways.