RESUMO
Although acute encephalopathy is quite commonly seen in patients of SARS-CoV-2 infection, encephalitis characterised by brain inflammation is relatively rare. Encephalitis caused by Herpes simplex type 1 is the most common cause of identified sporadic encephalitis, and early diagnosis and prompt treatment can prevent the devastating outcome. In this brief communication, we report a case of SARS-CoV-2 associated haemorrhagic encephalitis mimicking herpes encephalitis. In today's pandemic era, it is especially important to distinguish herpes encephalitis from SARS-CoV-2-associated encephalitis as treatment and prognosis of both the conditions differ greatly. This case highlights the importance of suspecting SARS-CoV-2 infection in a patient presenting with clinical symptoms and brain imaging suggestive of Herpes encephalitis.
Assuntos
COVID-19 , Encefalite por Herpes Simples , Encefalite Viral , Herpes Simples , COVID-19/diagnóstico , Encefalite por Herpes Simples/diagnóstico , Encefalite por Herpes Simples/tratamento farmacológico , Encefalite Viral/diagnóstico , Encefalite Viral/tratamento farmacológico , Humanos , Pandemias , SARS-CoV-2RESUMO
BACKGROUND: Paraneoplastic Cerebellar degeneration (PCD) is one of the classical paraneoplastic syndromes (PNS) which is characterised by subacute onset, progressive cerebellar ataxia and is usually associated with small cell lung carcinoma, adeno carcinoma of breast and ovary followed by Hodgkin's lymphoma. OBJECTIVE: We herein report a case of subacute onset, progressive cerebellar ataxia in a 37-year-old female, who on evaluation was found to have non-Hodgkin's lymphoma and experienced good clinical response to treatment. DISCUSSION: As compared to solid tumours, chances of association of PNS with Lymphomas is quite low and there are only few case reports in the literature showing association of PCD with non-Hodgkin's lymphoma. As PCD is one of the classical PNS, it is very important to identify subtle cerebellar manifestations in an otherwise apparently normal individual, as early diagnosis and aggressive treatment can immensely improve the mortality and morbidity associated with this syndrome. CONCLUSION: This case signifies the importance of suspecting PNS as an important differential diagnosis in a young patient presenting with subacute onset progressive cerebellar ataxia and evaluating her extensively for malignancy in spite of no paraneoplastic antibody been detected as early diagnosis and treatment can lead to gratifying response. We do agree that 2 weeks follow up is a short time interval to determine whether the response was sustained or not, for which a long term follow up is required.
Assuntos
Ataxia Cerebelar , Doença de Hodgkin , Linfoma não Hodgkin , Degeneração Paraneoplásica Cerebelar , Adulto , Cerebelo , Feminino , Humanos , Linfoma não Hodgkin/complicações , Linfoma não Hodgkin/diagnóstico , Degeneração Paraneoplásica Cerebelar/diagnósticoRESUMO
Covid-19-associated neurological manifestations are being reported with increased frequency throughout the world. In a study from China, symptoms referable to peripheral nervous system (PNS) were described in approximately 9% of hospitalized Covid-19 patients. Common PNS symptoms reported in the study were loss of taste/smell and muscle pains. With this communication, we expand the spectrum of PNS manifestations of Covid-19 infection by reporting an association of steroid responsive diffuse anterior horn cell disease with Covid-19 infection from a tertiary care centre in India. Neurological manifestations of Covid-19 are diverse, and our case which to best of my knowledge is the first case in literature to report an occurrence of steroid responsive diffuse anterior horn cell disease associated with Covid-19 infection, adds to the ever-increasing spectrum of neurological manifestations associated with this pandemic causing virus. Good response to steroid in our case serves to provide an insight into the possible pathogenesis of this manifestation and also paves the way for future therapeutic decisions related to this association.
Assuntos
COVID-19 , Doença dos Neurônios Motores , Doenças do Sistema Nervoso , Humanos , SARS-CoV-2 , Esteroides/uso terapêuticoRESUMO
BACKGROUND: Globally, more than 12 million people have been infected with COVID -19 infection till date with more than 500,000 fatalities. Although, Covid-19 commonly presents with marked respiratory symptoms in the form of cough and dyspnoea, a neurotropic presentation has been described of late as well. OBJECTIVE: In this brief communication we report four cases of Covid-19 who presented to our hospital with features suggestive of Guillain-Barre Syndrome (GBS). DISCUSSION: The mechanisms by which SARS-CoV-2 causes neurologic damage are multifaceted, including direct damage to specific receptors, cytokine-related injury, secondary hypoxia, and retrograde travel along nerve fibres. The pathogenesis of GBS secondary to Covid-19 is not well understood. It is hypothesised that viral illnesses related GBS could be due to autoantibodies or direct neurotoxic effects of viruses. CONCLUSION: Nervous system involvement in Covid-19 may have been grossly underestimated. In this era of pandemic, it is very important for the physicians to be aware of association of GBS with Covid-19, as early diagnosis and treatment of this complication could have gratifying results. To the best of our knowledge, this is the first such case series of Guillain-Barre Syndrome associated with Covid-19 to be reported from India.
Assuntos
COVID-19/diagnóstico , Síndrome de Guillain-Barré/diagnóstico , Idoso , COVID-19/complicações , Feminino , Síndrome de Guillain-Barré/virologia , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Centros de Atenção TerciáriaAssuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico por imagem , Leucoencefalite Hemorrágica Aguda/diagnóstico por imagem , Leucoencefalite Hemorrágica Aguda/etiologia , Pneumonia Viral/complicações , Pneumonia Viral/diagnóstico por imagem , Adulto , COVID-19 , Evolução Fatal , Humanos , Masculino , Pandemias , SARS-CoV-2RESUMO
We report the results of studies related to the fabrication of a nanostructured graphene oxide (GO)-based electrochemical genosensor for neonatal sepsis detection. Initially, we selected the fimA gene of E. coli for nenonatal sepsis detection and further designed a 20-mer long amine-terminated oligonucleotide. This designed oligonucleotide will work as a bioreceptor for the detection of the virulent fimA gene. An electrochemical genosensor was further developed where GO was used as an immobilization matrix. For the formation of a thin film of GO on an indium tin oxide (ITO)-coated glass electrode, an optimized DC potential of 10 V for 90 s was applied via an electrophoretic deposition unit. Thereafter, the designed oligonucleotides were immobilized through EDC-NHS chemistry. The nanomaterial and fabricated electrodes were characterized via X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and cyclic voltammetry techniques. The fabricated genosensor (BSA/pDNA/GO/ITO) has the ability to detect the target fimA gene with a linear detection range of 10-12 M to 10-6 M, a lower detection limit of 10-12 M and a sensitivity of 114.7 µA M-1 cm-2. We also investigated the biosensing ability of the developed genosensor in an artificial serum sample and the obtained electrochemical results were within the acceptable percentage relative standard deviation (% RSD), indicating that the fabricated genosensor can be used for the detection of neonatal sepsis by using a serum sample.
Assuntos
Técnicas Biossensoriais , Nanoestruturas , Sepse Neonatal , Humanos , Recém-Nascido , Sepse Neonatal/diagnóstico , Escherichia coli , Técnicas Biossensoriais/métodos , Nanoestruturas/química , OligonucleotídeosRESUMO
Neonatal sepsis is considered as alarming medical emergency and becomes the common global reason of neonatal mortality. Non-specific symptoms and limitations of conventional diagnostic methods for neonatal sepsis mandate fast and reliable method to diagnose disease for point of care application. Recently, disease specific biomarkers have gained interest for rapid diagnosis that led to the development of electrochemical biosensor with enhanced specificity, sensitivity, cost-effectiveness and user-friendliness. Other than conventional biomarker C-reactive protein to diagnose neonatal sepsis, several potential biomarkers including Procalcitonin (PCT), Serum amyloid A (SAA) and other candidates are extensively investigated. The present review provides insights on advancements and diagnostic abilities of protein and nucleotide based biomarkers with their incorporation in developing electrochemical biosensors by employing novel fabrication strategies. This review provides an overview of most promising biomarker and its capability for neonatal sepsis diagnosis to fulfil future demand to develop electrochemical biosensor for point-of-care applications.
Assuntos
Sepse Neonatal , Recém-Nascido , Humanos , Sepse Neonatal/diagnóstico , Biomarcadores , Sistemas Automatizados de Assistência Junto ao LeitoRESUMO
The current outbreak of a novel coronavirus, named as SARS-CoV-2 causing COVID-19 occurred in 2019, is in dire need of finding potential therapeutic agents. Recently, ongoing viral epidemic due to coronavirus (SARS-CoV-2) primarily affected mainland China that now threatened to spread to populations in most countries of the world. In spite of this, there is currently no antiviral drug/ vaccine available against coronavirus infection, COVID-19. In the present study, computer-aided drug design-based screening to find out promising inhibitors against the coronavirus (SARS-CoV-2) leads to infection, COVID-19. The lead therapeutic molecule was investigated through docking and molecular dynamics simulations. In this, binding affinity of noscapines(23B)-protease of SARS-CoV-2 complex was evaluated through MD simulations at different temperatures. Our research group has established that noscapine is a chemotherapeutic agent for the treatment of drug resistant cancers; however, noscapine was also being used as anti-malarial, anti-stroke and cough-suppressant. This study suggests for the first time that noscapine exerts its antiviral effects by inhibiting viral protein synthesis.
Assuntos
COVID-19 , Noscapina , Antivirais/farmacologia , Cisteína Endopeptidases , Humanos , Simulação de Acoplamento Molecular , Peptídeo Hidrolases , Inibidores de Proteases/farmacologia , SARS-CoV-2 , Temperatura , Proteínas não Estruturais ViraisRESUMO
Coronavirus disease-2019 (COVID-19) is a global health emergency and the matter of serious concern, which has been declared a pandemic by WHO. Till date, no potential medicine/ drug is available to cure the infected persons from SARS-CoV-2. This deadly virus is named as novel 2019-nCoV coronavirus and caused coronavirus disease, that is, COVID-19. The first case of SARS-CoV-2 infection in human was confirmed in the Wuhan city of the China. COVID-19 is an infectious disease and spread from man to man as well as surface to man . In the present work, in silico approach was followed to find potential molecule to control this infection. Authors have screened more than one million molecules available in the ZINC database and taken the best two compounds based on binding energy score. These lead molecules were further studied through docking against the main protease of SARS-CoV-2. Then, molecular dynamics simulations of the main protease with and without screened compounds were performed at room temperature to determine the thermodynamic parameters to understand the inhibition. Further, molecular dynamics simulations at different temperatures were performed to understand the efficiency of the inhibition of the main protease in the presence of the screened compounds. Change in energy for the formation of the complexes between the main protease of novel coronavirus and ZINC20601870 as well ZINC00793735 at room temperature was determined on applying MM-GBSA calculations. Docking and molecular dynamics simulations showed their antiviral potential and may inhibit viral replication experimentally. Communicated by Ramaswamy H. Sarma.
Assuntos
COVID-19 , Preparações Farmacêuticas , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peptídeo Hidrolases , Inibidores de Proteases/farmacologia , SARS-CoV-2RESUMO
Chalcone, a privileged structure, is considered as an effective template in the field of medicinal chemistry for potent drug discovery. In the present study, a privileged template chalcone was designed, synthesized, and characterized by various spectroscopic techniques (NMR, high-resolution mass spectrometry, Fourier transform infrared (FT-IR) spectroscopy, UV spectroscopy, and single-crystal X-ray diffraction). The mechanism of binding of chalcone with bovine serum albumin (BSA) was determined by multispectroscopic techniques and computational methods. Steady-state fluorescence spectroscopy suggests that the intrinsic fluorescence of BSA was quenched upon the addition of chalcone by the combined dynamic and static quenching mechanism. Time-resolved spectroscopy confirms complex formation. FT-IR and circular dichroism spectroscopy suggested the presence of chalcone in the BSA molecule microenvironment and also the possibility of rearrangement of the native structure of BSA. Moreover, molecular docking studies confirm the moderate binding of chalcone with BSA and the molecular dynamics simulation analysis shows the stability of the BSA-drug complex system with minimal deformability fluctuations and potential interaction by the covariance matrix. Moreover, pharmacodynamics and pharmacological analysis show good results through Lipinski rules, with no toxicity profile and high gastrointestinal absorptions by boiled egg permeation assays. This study elucidates the mechanistic profile of the privileged chalcone scaffold to be used in therapeutic applications.
RESUMO
Lysozyme is a well-characterized protein in terms of its structure, dynamics, and functions. It has thus emerged as a potential target to understand protein-drug interactions. The aim of our study is to gain a biophysical outlook on the interaction of lysozyme (Lyz), a well-known model protein, with Noscapine, a potent tubulin-binding anticancer drug. Noscapine (Nos) is effective against a wide range of cancer and shows low toxicity and few side effects. We report the underlying mechanism of complex formation between Nos and Lyz using spectroscopic and advanced computational avenues. The spectroscopic techniques, that is, absorption and steady-state and time-resolved fluorescence, proved that Lyz-Nos forms a complex, and the quenching mechanism was of the static type. The binding constant was in the order of 103 indicative of moderate binding, while the stoichiometry of the protein-drug complex was 1:1 at 298 K. The secondary structural analysis using CD and UV thermal denaturation further confirmed the conformational changes in the protein upon binding with Nos. Molecular dynamics simulation studies confirmed the stable binding with minimum deviations in RMSD. The above conclusions are significant to the development of the pharmacokinetics and pharmacodynamic properties of Nos, and its successful interaction with a versatile protein like Lyz will help in overcoming its previous limitations.
RESUMO
The prevalence of obesity is increasing at an alarming rate worldwide with about 30% of the world population classified as obese. Obese body structure results when energy intake exceeds energy expenditure in an individual. Increase in the consumption of high-energy eatables, in the context of portion and energy provided, has resulted in obese populations which is becoming the leading cause of metabolic disorders related to morbidity. The obesity-related comorbidity is an enormous liability on health services and will affect measures taken in tackling the increasing obesity rate. Prevention of an obese phenotype is the most suitable long-term strategy. Another approach towards the treatment of obesity is weight management through phytotherapeutics. In this study, we explored the anti-obesity effects of Cinnamon (Cinnamomum zeylanicum) in adult male zebrafish. Through BMI measurements, blood glucose level analyses, serum triglyceride analyses, Oil Red O staining as well as quantitative Real Time-PCR, the ability of cinnamon to reduce metabolic disorders associated with obesity is investigated for the first time in a zebrafish model. Our studies indicate that cinnamon ameliorates the genotypic and phonotypic characteristics associated with obesity through lowering of BMI, blood glucose, triglyceride levels, lipid levels in the liver and through gene modulation.
Assuntos
Adiposidade/efeitos dos fármacos , Glicemia/metabolismo , Cinnamomum zeylanicum/química , Dieta/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Obesidade/metabolismo , Obesidade/patologia , Animais , Índice de Massa Corporal , Tamanho Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Fígado/efeitos dos fármacos , Fígado/patologia , Obesidade/etiologia , Obesidade/genética , Triglicerídeos/sangue , Peixe-ZebraRESUMO
In present investigation, an attempt was undertaken to modify the C-9 position of noscapine (Nos), an opium alkaloid to yield 9 -hydroxy methyl and 9 -carbaldehyde oxime analogues for augmenting anticancer potential. The synthesis of 9-hydroxy methyl analogue of Nos was carried out by Blanc reaction and 9-carbaldehyde oxime was engineered by oxime formation method and characterized using FT-IR, 1H NMR, 13C NMR, mass spectroscopy, and so on techniques. In silico docking techniques informed that 9-hydroxy methyl and 9-carbaldehyde oxime analogues of Nos had higher binding energy score as compared to Nos. The IC50 of Nos was estimated to be 46.8 µM signficantly (P < 0.05) higher than 8.2 µM of 9-carbaldehyde oxime and 4.6 µM of 9-hydroxy methyl analogue of Nos in U87, human glioblastoma cells. Moreover, there was significant (P < 0.05) difference between the IC50 of 9-carbaldehyde oxime and 9-hydroxy methyl analogue of Nos. Consistent to in vitro cytotoxicity data, 9-hydroxy methyl analogue of Nos induced significantly (P < 0.05) higher degree of apoptosis of 84.6% in U87 cells as compared to 78.5% and 64.3% demonstrated by 9-carbaldehyde oxime and Nos, respectively. Thus the higher therapeutic efficacy of 9-hydroxy methyl analogue of Nos may be credited to higher solubility and inhibitory constant (K).
Assuntos
Antineoplásicos/farmacologia , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Noscapina/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Espectroscopia de Ressonância Magnética , Noscapina/análogos & derivados , Oximas/metabolismo , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Gossypol--a male contraceptive is toxic and causes anorexia, reduction in body weight, hypokalemia etc. It prevents liberation of oxygen from oxyhemoglobin and has hemolytic effect on erythrocytes and leads to microcytic hypochromic anemia. SnPP has been shown to either competitively suppress or to significantly ameliorate a variety of naturally occuring or experimentally induced forms of jaundice in animals and man by inhibiting heme degradation. In this paper novel tissue-dependent response to differential dosing regimen of gossypol and gossypol in association with Sn-protoporphyrin (SnPP) is described. Gossypol was found to be a stimulator of heme oxygenase activity in the liver and kidney to varying degrees. This tissue response contrasted with that of the spleen, where gossypol decreased the activity of the enzyme. The increase in enzymatic activity was accompanied by a decline in the total microsomal protein content on gossypol administration. The gossypol mediated an increase of heme oxygenase activity, elevated bilirubin levels leading to hyperbilirubinemia. The stimulatory effect of gossypol was counteracted to a considerable extent when SnPP was simultaneously administered. Hence, we envision the importance of combined rather than single exposures in defining the realms of toxicology of these and other related drugs. We further envisage the existence of important gossypol-heme interactions in the regulation of heme metabolism.
Assuntos
Gossipol/farmacologia , Heme Oxigenase (Desciclizante)/metabolismo , Metaloporfirinas/farmacologia , Microssomos/efeitos dos fármacos , Protoporfirinas/farmacologia , Animais , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Gossipol/química , Heme Oxigenase (Desciclizante)/antagonistas & inibidores , Masculino , Metaloporfirinas/química , Microssomos/metabolismo , Protoporfirinas/química , Ratos , Ratos WistarRESUMO
The present study evaluates the effect of oral administration of papaverine at differential dosing regimens (100 mg/kg bw and 200 mg/kg bw) on the hepatic and pulmonary glutathione S-transferase (GST) activity and glutathione content (GSH) in male Wistar rats. Papaverine treatment caused a pronounced increase in GST activity and GSH content at the higher dosing level in the rat liver and lung. We conclude that papaverine, can possibly act as a chemopreventive agent against chemical carcinogenesis.
Assuntos
Glutationa Transferase/metabolismo , Glutationa/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Papaverina/farmacologia , Animais , Anticarcinógenos/farmacologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Masculino , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/enzimologia , Mitocôndrias Hepáticas/metabolismo , Ratos , Ratos WistarRESUMO
This review introduces the Noscapine, which is being used as an antitussive drug for a long time has been recently discovered as a novel tubulin-binding, anti-angiogenic anticancer drug that causes cell cycle arrest and induces apoptosis in cancer cells both in vitro as well as in vivo. Noscapine is a multifunctional molecule i.e. it possesses various functional moieties. We maneuvered various amenable sites and have synthesized analogs, which might prove to be more efficacious and less cytotoxic. Moreover, development of oral controlled release anticancer formulation of noscapine is severely hampered due to short biological half-life (<2-h), poor absorption, low aqueous solubility, and extensive first pass metabolism, thereby requiring large doses for effective treatment.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antitussígenos/farmacologia , Heme/metabolismo , Noscapina/farmacologia , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Antitussígenos/uso terapêutico , Ciclo Celular , Humanos , Microtúbulos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Noscapina/uso terapêuticoRESUMO
Noscapine, a tubulin binding anticancer agent undergoing Phase I/II clinical trials, inhibits tumor growth in nude mice bearing human xenografts of breast, lung, ovarian, brain, and prostrate origin. The analogues of noscapine like 9-bromonoscapine (EM011) are 5 to 10-fold more active than parent compound, noscapine. Noscapinoids inhibit the proliferation of cancer cells that are resistant to paclitaxel and epothilone. Noscapine also potentiated the anticancer activity of doxorubicin in a synergistic manner against triple negative breast cancer (TNBC). However, physicochemical and pharmacokinetic (ED50Ë300-600 mg/kg bodyweight) limitations of noscapine present hurdle in development of commercial anticancer formulations. Therefore, objectives of the present review are to summarize the chemotherapeutic potential of noscapine and implications of nanoscale based drug delivery systems in enhancing the therapeutic efficacy of noscapine in cancer cells. We have constructed noscapine-enveloped gelatin nanoparticles, NPs and poly (ethylene glycol) grafted gelatin NPs as well as inclusion complex of noscapine in ß-cyclodextrin (ß-CD) and evaluated their physicochemical characteristics. The Fe3O4 NPs were also used to incorporate noscapine in its polymeric nanomatrix system where molecular weight of the polymer governed the encapsulation efficiency of drug. The enhanced noscapine delivery using µPAR-targeted optical-MR imaging trackable NPs offer a great potential for image directed targeted delivery of noscapine. Human Serum Albumin NPs (150-300 nm) as efficient noscapine drug delivery systems have also been developed for potential use in breast cancer.
Assuntos
Antineoplásicos/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Noscapina/administração & dosagem , Tubulina (Proteína)/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Ciclodextrinas/química , Sistemas de Liberação de Medicamentos , Humanos , Nanopartículas/química , Neoplasias/metabolismo , Noscapina/química , Noscapina/farmacocinética , Albumina Sérica/químicaRESUMO
In the present work, we report the synthesis and characterization of novel charge-transfer complexes of thiazolidine-2,4-dione (TZD) with sigma acceptor (iodine) and pi acceptors (chloranil, dichlorodicyanoquinone, picric acid and duraquinone). We also evaluated their thermal and electrochemical properties and we conclude that these complexes are frequency dependent. Charge-transfer complex between thiazolidine-2,4-dione and iodine give best conductivity. In conclusion, complex with sigma acceptors are more conducting than with pi acceptors.
Assuntos
Eletroquímica , Tiazolidinedionas/química , Cloranila/química , Eletroquímica/métodos , Fungicidas Industriais/química , Iodo/química , Estrutura Molecular , Picratos/química , Quinonas/química , Termogravimetria , Oligoelementos/química , Desacopladores/químicaRESUMO
Glutathione-S-transferases and glutathione play a key role in the detoxification of most toxic agents. In the present study, the protective effects, if any, of isoflavone phytoestrogens--genistein and daidzein on the carbon tetrachloride (CCl4) induced changes in the activity of alanine aminotransferase (ALT), aspartate aminotransferase (AST), glutathione S transferase (GSH) and levels of glutathione (GSH) and thiobarbituric acid reactive substances (TBARS)-were studied. The activities of ALT and AST were assayed in the serum, whereas the activity of GST and levels of GSH and TBARS were determined in the livers of rats. The current study involved the division of animals into two main groups: (i) rats pretreated with genistein and daidzein for three days; and (ii) non-pretreated rats. In the pretreated group, rats received oral doses of genistein (7.9 micromol/kg body weight) and daidzein (7.9 micromol/kg body weight) for three consecutive days (once daily) followed by oral dose of CCl4 on the 4th and the 5th day concurrently with the phytoestrogens-genistein or daidzein. In the non-pretreated group animals received oral dose of CCl4 (1 ml/kg body weight) for two consecutive days along with the phytoestrogens-genistein or daidzein. Treatment of male rats with CCl4 significantly elevated the activity of ALT and AST in serum and levels of TBARS in the liver. On the other hand, CCl4 resulted in decreased activity of GST and lowered the GSH levels. Coadministration of genistein and daidzein with CCl4 could not restore the alterations in the activity of ALT and AST caused by CCl4 to normal control levels. However, repeated dose treatments with genistein and daidzein for three days prior to the administration of CCl4 restored such alterations to normal levels. Our results indicate that genistein is more effective than daidzein in counteracting the inhibition of GST activity caused by CCl4 and restoring it to normal levels. Genistein was also more effective than daidzein restoring the induced TBARS levels caused by CCl4 to normal control levels when rats were pretreated with the isoflavone orally for three days. It has been observed that the tested isoflavonoids were able to antagonize the toxic effects of CCl4. Such counteracting effects were more pronounced for genistein and when the phytoestrogens were administered as repeated doses prior CCl4 administration.