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1.
Sci Rep ; 14(1): 4828, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38413650

RESUMO

The agroforestry system is the best option to achieve the net zero carbon emissions target for India. Keeping this view, carbon sequestration and credit potential of gamhar based agroforestry system has been assessed. The experiment was carried out in randomized block design in seven different treatments with five replications. Gamhar tree biomass accumulation was higher in gamhar based agroforestry system compared to sole gamhar. Among different tree components, stem contributed a maximum to total gamhar tree biomass followed by roots, leaves and branches. The average contributions of stems, roots, leaves and branches in total tree biomass in two annual cycles (2016-17 and 2017-18) varied between 50 and 60, 19.8 and 20, 19.2 and 20, and 10.7 and 12.7 percent, respectively. In case of crops, above ground, below ground and total biomass was significantly higher in sole intercrops than gamhar based agroforestry system. Total (Tree + interrops + Soil) carbon stock, carbon sequestration, carbon credit and carbon price were significantly affected by treatments, and was maximum in Sole Greengram-Mustard. Net carbon emission was also recorded lowest in Sole Greengram-Mustard for which the values were 811.55% and 725.24% and 760.69% lower than Sole Gamhar in 2016-17, 2017-18 and in pooled data, respectively.


Assuntos
Sequestro de Carbono , Carbono , Árvores , Solo , Biomassa
2.
Front Cell Infect Microbiol ; 13: 1269344, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38094741

RESUMO

Drugs and chemotherapeutics have helped to manage devastating impacts of infectious diseases since the concept of 'magic bullet'. The World Health Organization estimates about 650,000 deaths due to respiratory diseases linked to seasonal influenza each year. Pandemic influenza, on the other hand, is the most feared health disaster and probably would have greater and immediate impact on humanity than climate change. While countermeasures, biosecurity and vaccination remain the most effective preventive strategies against this highly infectious and communicable disease, antivirals are nonetheless essential to mitigate clinical manifestations following infection and to reduce devastating complications and mortality. Continuous emergence of the novel strains of rapidly evolving influenza viruses, some of which are intractable, require new approaches towards influenza chemotherapeutics including optimization of existing anti-infectives and search for novel therapies. Effective management of influenza infections depend on the safety and efficacy of selected anti-infective in-vitro studies and their clinical applications. The outcomes of therapies are also dependent on understanding diversity in patient groups, co-morbidities, co-infections and combination therapies. In this extensive review, we have discussed the challenges of influenza epidemics and pandemics and discoursed the options for anti-viral chemotherapies for effective management of influenza virus infections.


Assuntos
Influenza Humana , Infecções por Orthomyxoviridae , Orthomyxoviridae , Humanos , Influenza Humana/epidemiologia , Infecções por Orthomyxoviridae/tratamento farmacológico , Terapia Combinada , Pandemias , Antivirais/uso terapêutico
3.
Microb Pathog ; 183: 106330, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37661072

RESUMO

The present study was aimed to investigate the role of cannibalism in transmission of H5N1 avian influenza virus to house crows (Corvus splendens). Four crows were intranasally inoculated with 108.0 EID50 (A/crow/India/01CA249/2021) H5N1 highly pathogenic avian influenza (HPAI) virus and were observed for 14 days for any overt signs of illness. Two of the infected crows showed signs of wing paralysis, incoordination, and torticollis. For cannibalism experiment, two crows showing clinical signs were euthanized on 14th day post-infection (dpi) and were kept in the isolator and four naïve healthy crows were introduced along with the euthanized crows. The viscera from the infected carcasses were eaten by all the four crows. Oropharyngeal and cloacal swabs were collected up to 14 days to assess virus excretion. All four crows showed clinical signs viz., dullness, reluctance to move with ruffled feathers on 6th day post cannibalism along with neurological signs including incoordination and paralysis of the wings. All the crows gradually recovered after showing clinical signs and were euthanized on 21st day of observation period. Virus excretion was observed from 3rd to 11th day post cannibalism through both oropharyngeal and cloacal routes with maximum shedding through oropharyngeal route. The virus was isolated from lungs and trachea of one the infected crows at 21st day after euthanasia. All the four crows seroconverted against H5N1 virus infection at 14th day post cannibalism. Our study confirms the transmission of H5N1 virus in crows through cannibalism and highlights how H5N1 virus might circulate in a crow colony once they become infected.


Assuntos
Corvos , Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Influenza Aviária , Animais , Paralisia , Ingestão de Alimentos
4.
Front Mol Biosci ; 10: 1158133, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37325475

RESUMO

The emergence and re-emergence of viral diseases, which cause significant global mortality and morbidity, are the major concerns of this decade. Of these, current research is focused majorly on the etiological agent of the COVID-19 pandemic, SARS-CoV-2. Understanding the host response and metabolic changes during viral infection may provide better therapeutic targets for the proper management of pathophysiological conditions associated with SARS-CoV-2 infection. We have achieved control over most emerging viral diseases; however, a lack of understanding of the underlying molecular events prevents us from exploring novel therapeutic targets, leaving us forced to witness re-emerging viral infections. SARS-CoV-2 infection is usually accompanied by oxidative stress, which leads to an overactive immune response, the release of inflammatory cytokines, increasing lipid production, and also alterations in the endothelial and mitochondrial functions. PI3K/Akt signaling pathway confers protection against oxidative injury by various cell survival mechanisms including Nrf2-ARE mediated antioxidant transcriptional response. SARS-CoV-2 is also reported to hijack this pathway for its survival within host and few studies have suggested the role of antioxidants in modulating the Nrf2 pathway to manage disease severity. This review highlights the interrelated pathophysiological conditions associated with SARS-CoV-2 infection and the host survival mechanisms mediated by PI3K/Akt/Nrf2 signaling pathways that can help ameliorate the severity of the disease and provide effective antiviral targets against SARS-CoV-2.

5.
Indian J Clin Biochem ; 37(4): 441-448, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36262783

RESUMO

Quinacrine is an Acridine derivative with two potentially reactive groups; a diamino butyl side chain and an Acridine ring both capable of interacting with DNA but in different ways. This is an antimalarial drug approved by FDA for long term clinical trials and for the treatment of other diseases as well. The study evaluates the physicochemical interactions of quinacrine with DNA (calf thymus DNA) through characterizations of quinacrine DNA adduct (Q-DNA) by various techniques. It was observed that quinacrine induces stability in the structure of DNA, as the onset of melting was found to be increased by 6 °C in the melting temperature profile of Q-DNA supported by other data obtained during study, deviation from the native structure of DNA was analyzed by FTIR that showed specific shifts in the region of 1707-1400 cm-1.The study also probed the antigenicity of Q-DNA compared to its non antigenic native counterpart (N-DNA), by using both as antigens in female New Zealand White rabbits. Q-DNA was found to be antigenic with antibody titer > 1:6400. IgG was isolated and characterized to check for binding specificity. These antibodies were found to be promiscuous capable of cross reacting with other cellular molecules. Analysis of the data obtained suggested that intracellular accumulation of quinacrine and its ability to cross nucleus may allow the drug to interact with DNA. This may bring about significant structural perturbations in the macromolecule triggering an immunogenic response at the site where anti Q-DNA antibody and Q-DNA complex accumulates.

6.
RSC Adv ; 12(20): 12552-12563, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35496341

RESUMO

n/n/n triple heterojunction photoanodes made up of Zr:W-BiVO4, Fe2O3, and ZnFe2O4 metal oxides are fabricated through a simplistic spray pyrolysis method. Use of Zr and W as dopants in BiVO4 plays an important role as Zr increases the carrier density and W reduces the charge recombination. Further, Fe2O3 and ZnFe2O4 serve as a protective layer for Zr:W-BiVO4, which augmented the photoelectrochemical performance and achieved a 1.90% conversion efficiency in the triple heterojunction. XRD measurements display the crystalline nature and reduction in particle size due to strain in the sample, UV-vis absorbance shows an extended absorption towards the visible region and the FE-SEM imaging confirms the successful deposition of ZnFe2O4 over BiVO4/Fe2O3. By analyzing the band edge position, it was observed that on formation, the triple heterojunction not only suppresses the charge carrier recombination but also utilizes the band edge offset for the water splitting reaction using solar energy.

7.
Pathogens ; 11(3)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35335628

RESUMO

This study aimed to investigate the potential of H9N2 avian influenza virus to cause disease and intra-species transmission in house crows (Corvus splendens). A group of six crows were intranasally inoculated with 106.0 EID50 of H9N2 virus (A/chicken/India/07OR17/2021), and 24 h post-inoculation six naïve crows were co-housed with infected crows. Crows were observed for 14 days for any overt signs of illness. Oropharyngeal and cloacal swabs were collected up to 14 days to assess virus excretion. No apparent clinical signs were observed in either infected or in-contact crows. Virus excretion was observed only in infected birds up to 9 days post-infection (dpi) through both oropharyngeal and cloacal routes. All six infected crows seroconverted to H9N2 virus at 14 dpi, whereas all in-contact crows remained negative to H9N2 virus antibodies. No virus could be isolated from tissues viz., lung, liver, kidney, pancreas, small intestine and large intestine. Although crows became infected with the H9N2 virus, transmission of the virus was inefficient to the in-contact group. However, virus excretion through oral and cloacal swabs from infected crows suggests a potential threat for inter-species transmission, including humans. Crows, being a common synanthrope species, might have some role in influenza virus transmission to poultry and humans, which needs to be explored further.

9.
Adv Exp Med Biol ; 1313: 59-83, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34661891

RESUMO

Respiratory viral infections often lead to severe illnesses varying from mild or asymptomatic upper respiratory tract infections to severe bronchiolitis and pneumonia or/and chronic obstructive pulmonary disease. Common viral infections, including but not limited to influenza virus, respiratory syncytial virus, rhinovirus and coronavirus, are often the leading cause of morbidity and mortality. Since the lungs are continuously exposed to foreign particles, including respiratory pathogens, it is also well equipped for recognition and antiviral defense utilizing the complex network of innate and adaptive immune cells. Immediately upon infection, a range of proinflammatory cytokines, chemokines and an interferon response is generated, thereby making the immune response a two edged sword, on one hand it is required to eliminate viral pathogens while on other hand it's prolonged response can lead to chronic infection and significant pulmonary damage. Since vaccines to all respiratory viruses are not available, a better understanding of the virus-host interactions, leading to the development of immune response, is critically needed to design effective therapies to limit the severity of inflammatory damage, enhance viral clearance and to compliment the current strategies targeting the virus. In this chapter, we discuss the host responses to common respiratory viral infections, the key players of adaptive and innate immunity and the fine balance that exists between the viral clearance and immune-mediated damage.


Assuntos
Coronavirus , Infecções Respiratórias , Viroses , Humanos , Imunidade Inata , Pulmão
10.
Braz J Microbiol ; 52(4): 2541-2546, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34241826

RESUMO

Shiga toxigenic Escherichia coli (STEC) is one of the most important food-borne zoonotic bacterial pathogens responsible for causing gastrointestinal infections, haemorrhagic colitis and haemolytic uremic syndrome. The present study was aimed to isolate and characterize STEC from neonatal dairy calves, animal handlers and their surrounding environment and to establish the genetic relationship among isolates by multilocus sequence typing (MLST). A total number of 115 samples were collected and processed for the isolation of E. coli. The occurrence rate of E. coli was 92.2% (106/115), of which, 18 were typed as STEC. Antibacterial susceptibility analysis revealed 11 (61.1%) strains as multiple drug-resistant (MDR). MLST analysis has delineated 16 sequence types (STs) including nine novel STs. Among STs, ST58 dominated with three strains and was recovered from the environment and neonatal calves. Strains from neonatal calves and humans showed genetic relatedness with significant bootstrap support values indicative of zoonotic transmission potentiality. Analysis of 211 global isolates belonging to 61 STs indicated predominant STs (ST 21, ST 33 and ST 3416) that can be either host-specific (ST 33 and ST 3416) or can be shared among human and bovine hosts (ST 21). The MLST analysis indicates genetic relatedness among isolates and the results predispose inter-host transmission and zoonotic spread.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli Shiga Toxigênica , Animais , Antibacterianos , Zoonoses Bacterianas , Bovinos/microbiologia , Farmacorresistência Bacteriana Múltipla , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Humanos , Tipagem de Sequências Multilocus , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/efeitos dos fármacos
11.
Biomaterials ; 275: 120966, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34147715

RESUMO

Non-viral vectors offer the potential to deliver nucleic acids including mRNA and DNA into cells in vivo. However, designing materials that effectively deliver to target organs and then to desired compartments within the cell remains a challenge. Here we develop polymeric materials that can be optimized for either DNA transcription in the nucleus or mRNA translation in the cytosol. We synthesized poly(beta amino ester) terpolymers (PBAEs) with modular changes to monomer chemistry to investigate influence on nucleic acid delivery. We identified two PBAEs with a single monomer change as being effective for either DNA (D-90-C12-103) or mRNA (DD-90-C12-103) delivery to lung endothelium following intravenous injection in mice. Physical properties such as particle size or charge did not account for the difference in transfection efficacy. However, endosome co-localization studies revealed that D-90-C12-103 nanoparticles resided in late endosomes to a greater extent than DD-90-C12-103. We compared luciferase expression in vivo and observed that, even with nucleic acid optimized vectors, peak luminescence using mRNA was two orders of magnitude greater than pDNA in the lungs of mice following systemic delivery. This study indicates that different nucleic acids require tailored delivery vectors, and further support the potential of PBAEs as intracellular delivery materials.


Assuntos
Nanopartículas , Polímeros , Animais , DNA , Lipídeos , Pulmão , Camundongos , RNA Mensageiro/genética , Transfecção
12.
Front Oncol ; 11: 654940, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34094947

RESUMO

The endoplasmic reticulum (ER) regulates protein folding, post-translational modifications, lipid synthesis, and calcium signaling to attenuate the accumulation of misfolded proteins causing ER stress and maintains cellular homeostasis. The tumor microenvironment is rich in soluble cytokines, chemokines, growth, and angiogenic factors and can drive the ER's abnormal functioning in healthy cells. Cancer cells adapt well to the tumor microenvironment induced ER stress. We identified that the inflammatory breast cancer (IBC) cells abundantly express osteoprotegerin (OPG) and their tumor microenvironment is rich in OPG protein. OPG also called osteoclast differentiation factor/osteoclastogenesis inhibitory factor (OCIF) is a soluble decoy receptor for receptor activator of nuclear factor-kappa B ligand (RANKL). Employing mass spectrometry analysis, we identified a set of ER chaperones associated with OPG in IBC cell lysates (SUM149PT, SUM1315MO2) compared to healthy human mammary epithelial cells (HMEC). Proximity ligation assay (PLA) and immunoprecipitation assay validated the interaction between OPG and ER chaperone and master regulator of unfolded protein response (UPR) GRP78/BiP (glucose-regulated protein/Binding immunoglobulin protein). We detected remarkably high gene expression of CCAAT enhancer-binding protein homologous protein (CHOP), inositol-requiring enzyme 1 (IRE1α), protein disulfide-isomerase (PDI), PKR-like ER kinase (PERK), activating transcription factor 4 (ATF4), X-box binding protein 1 (XBP-1) and growth arrest and DNA damage-inducible protein (GADD34) in SUM149PT and SUM190PT cells when compared to HMEC. Similarly, tissue sections of human IBC expressed high levels of ER stress proteins. We evaluated cell death and apoptosis upon Salubrinal and phenylbutyrate treatment in healthy and IBC cells by caspase-3 activity and cleaved poly (ADP-ribose) polymerase (PARP) protein assay. IBC (SUM149PT and SUM190PT) cells were chemosensitive to Salubrinal treatment, possibly via inhibition in OPG secretion, upregulating ATF4, and CHOP, thus ultimately driving caspase-3 mediated IBC cell death. Salubrinal treatment upregulated PDI, which connects ER stress to oxidative stress. We observed increased ROS production and reduced cell proliferation of Salubrinal treated IBC cells. Treatment with antioxidants could rescue IBC cells from ROS and aborted cell proliferation. Our findings implicate that manipulating ER stress with Salubrinal may provide a safer and tailored strategy to target the growth of inflammatory and aggressive forms of breast cancer.

13.
Front Cell Infect Microbiol ; 11: 603309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816328

RESUMO

Herpesviruses utilize various host factors to establish latent infection, survival, and spread disease in the host. These factors include host cellular machinery, host proteins, gene expression, multiple transcription factors, cellular signal pathways, immune cell activation, transcription factors, cytokines, angiogenesis, invasion, and factors promoting metastasis. The knowledge and understanding of host genes, protein products, and biochemical pathways lead to discovering safe and effective antivirals to prevent viral reactivation and spread infection. Here, we focus on the contribution of pro-inflammatory, anti-inflammatory, and resolution lipid metabolites of the arachidonic acid (AA) pathway in the lifecycle of herpesvirus infections. We discuss how various herpesviruses utilize these lipid pathways to their advantage and how we target them to combat herpesvirus infection. We also summarize recent development in anti-herpesvirus therapeutics and new strategies proposed or under clinical trials. These anti-herpesvirus therapeutics include inhibitors blocking viral life cycle events, engineered anticancer agents, epigenome influencing factors, immunomodulators, and therapeutic compounds from natural extracts.


Assuntos
Infecções por Herpesviridae , Herpesviridae , Regulação Viral da Expressão Gênica , Humanos , Ativação Viral , Latência Viral , Replicação Viral
14.
Int J Mol Sci ; 22(3)2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33494284

RESUMO

The hedgehog (SHH) signaling pathway is primarily involved in embryonic gut development, smooth muscle differentiation, cell proliferation, adult tissue homeostasis, tissue repair following injury, and tissue polarity during the development of vertebrate and invertebrate organisms. GLIoma-associated oncogene homolog (GLI) family of zinc-finger transcription factors and smoothened (SMO) are the signal transducers of the SHH pathway. Both SHH ligand-dependent and independent mechanisms activate GLI proteins. Various transcriptional mechanisms, posttranslational modifications (phosphorylation, ubiquitination, proteolytic processing, SUMOylation, and acetylation), and nuclear-cytoplasmic shuttling control the activity of SHH signaling pathway proteins. The dysregulated SHH pathway is associated with bone and soft tissue sarcomas, GLIomas, medulloblastomas, leukemias, and tumors of breast, lung, skin, prostate, brain, gastric, and pancreas. While extensively studied in development and sarcomas, GLI family proteins play an essential role in many host-pathogen interactions, including bacterial and viral infections and their associated cancers. Viruses hijack host GLI family transcription factors and their downstream signaling cascades to enhance the viral gene transcription required for replication and pathogenesis. In this review, we discuss a distinct role(s) of GLI proteins in the process of tumorigenesis and host-pathogen interactions in the context of viral infection-associated malignancies and cancers due to other causes. Here, we emphasize the potential of the Hedgehog (HH) pathway targeting as a potential anti-cancer therapeutic approach, which in the future could also be tested in infection-associated fatalities.


Assuntos
Proteínas Hedgehog/metabolismo , Neoplasias/metabolismo , Transdução de Sinais , Viroses/metabolismo , Animais , Biomarcadores , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Viral , Suscetibilidade a Doenças , Transição Epitelial-Mesenquimal , Regulação da Expressão Gênica , Proteínas Hedgehog/genética , Humanos , Terapia de Alvo Molecular , Neoplasias/etiologia , Neoplasias/patologia , Neoplasias/terapia , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Ligação Proteica , Transativadores/genética , Transativadores/metabolismo , Viroses/etiologia , Viroses/terapia
15.
Eur J Case Rep Intern Med ; 7(7): 001600, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32665926

RESUMO

Lisinopril is an angiotensin converting enzyme inhibitor (ACE-I) that has been on market for more than 25 years. ACE-I are usually well tolerated and rarely have serious or life-threatening side effects. We describe an unusual presentation of fulminant hepatic cholestasis probably secondary to lisinopril. To our knowledge, this is the second case report which shows lisinopril-induced liver injury though a cholestatic mechanism. The patient was a 59-year-old woman with type 2 diabetes, a high body mass index and hypertension, who presented with a 5-week history of jaundice and itching. She had been started on lisinopril for diabetic nephropathy 8 weeks before admission. Other causes for cholestasis had been excluded through non-invasive immunology and virology screening, an ultrasound of the liver, magnetic resonance cholangiopancreatography and a liver biopsy. The biopsy was consistent with drug-induced liver injury. Lisinopril was stopped 2 weeks before admission. The patient's hospital stay was complicated by contrast nephropathy and influenza A which were both treated appropriately. Unfortunately, the liver cholestasis did not completely resolve following withdrawal of lisinopril and the patient died after 4 months. A literature search yielded only six other reported cases of lisinopril-induced liver injury. Five cases described hepatocellular damage and one showed cholestatic injury. LEARNING POINTS: Angiotensin converting enzyme inhibitors (ACE-I) rarely have serious or life-threatening side effects.Lisinopril-induced liver injury can present as hepatocellular or cholestatic injury.Severe hepatotoxicity secondary to lisinopril can be life threatening irrespective of the liver injury pattern.

16.
Anaerobe ; 63: 102212, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32413405

RESUMO

Clostridium perfringens is a globally recognized zoonotic pathogen. We report isolation and genotyping of C. perfringens from neonatal calves, dairy workers and their associated environment in India. A total of 103 fecal samples from neonatal calves, 25 stool swabs from the dairy workers and 50 samples from their associated environment were collected from two dairy farms. C. perfringens was detected in 26 out of 103 (25.2%) neonatal calf samples, 7 out of 25 (28%) human stool samples and 17 out of 50 (34%) environmental samples. C. perfringens type A strains were predominant in neonatal calves (24/26; 92.3%) and associated environment (15/17; 88.2%). In contrast, strains from dairy workers mostly belonged to type F (5/7; 71.4%), which also carried the beta2 toxin gene. Seventeen strains were analyzed by multilocus sequence typing (MLST) for studying genotypic relationship along with 188 C. perfringens strains available from public databases. A total of 112 sequence types (STs) were identified from 205 C. perfringens strains analyzed. A Clonal complex (CC) represented by three STs (ST 98, ST 41 and ST 110) representing predominantly type F (18/20 strains) were mostly associated with human illnesses. Among predominant STs, ST 54 was associated with enteritis cases in foals and dogs and ST 58 associated with necrotic enteritis in poultry. Seventeen Indian strains were assigned to 13 STs. Genetic relatedness among strains of calves, dairy worker and associated environments indicate inter-host transfers and zoonotic spreads.


Assuntos
Infecções por Clostridium , Clostridium perfringens , Tipagem de Sequências Multilocus , Animais , Zoonoses Bacterianas , Bovinos , Doenças dos Bovinos/microbiologia , Infecções por Clostridium/transmissão , Infecções por Clostridium/veterinária , Clostridium perfringens/genética , Clostridium perfringens/isolamento & purificação , Enterotoxinas/genética , Microbiologia Ambiental , Fazendeiros , Fezes/microbiologia , Genes Bacterianos , Variação Genética , Humanos , Índia/epidemiologia , Tipagem de Sequências Multilocus/veterinária , Filogenia
17.
J Virol ; 94(9)2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32102879

RESUMO

Lipoxin A4 (LXA4) is an endogenous lipid mediator with compelling anti-inflammatory and proresolution properties. Studies done to assess the role of arachidonic acid pathways of the host in Kaposi's sarcoma-associated herpesvirus (KSHV) biology helped discover that KSHV infection hijacks the proinflammatory cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LO) pathways and concurrently reduces anti-inflammatory LXA4 secretion to maintain KSHV latency in infected cells. Treatment of KSHV-infected cells with LXA4 minimizes the activation of inflammatory and proliferative signaling pathways, including the NF-κB, AKT, and extracellular signal-regulated kinase 1/2 (ERK1/2) pathways, but the exact mechanism of action of LXA4 remains unexplored. Here, using mass spectrometry analysis, we identified components from the minichromosome maintenance (MCM) protein and chromatin-remodeling complex SMARCB1 and SMARCC2 to be LXA4-interacting host proteins in KSHV-infected cells. We identified a higher level of nuclear aryl hydrocarbon receptor (AhR) in LXA4-treated KSHV-infected cells than in untreated KSHV-infected cells, which probably facilitates the affinity interaction of the nucleosome complex protein with LXA4. We demonstrate that SMARCB1 regulates both replication and transcription activator (RTA) activity and host hedgehog (hh) signaling in LXA4-treated KSHV-infected cells. Host hedgehog signaling was modulated in an AMP-activated protein kinase (AMPK)-mammalian target of rapamycin (mTOR)-S6 kinase-dependent manner in LXA4-treated KSHV-infected cells. Since anti-inflammatory drugs are beneficial as adjuvants to conventional and immune-based therapies, we evaluated the potential of LXA4 treatment in regulating programmed death-ligand 1 (PD-L1) on KSHV-carrying tumor cells. Overall, our study identified LXA4-interacting host factors in KSHV-infected cells, which could help provide an understanding of the mode of action of LXA4 and its therapeutic potential against KSHV.IMPORTANCE The latent-to-lytic switch in KSHV infection is one of the critical events regulated by the major replication and transcription activator KSHV protein called RTA. Chromatin modification of the viral genome determines the phase of the viral life cycle in the host. Here, we report that LXA4 interacts with a host chromatin modulator, especially SMARCB1, which upregulates the KSHV ORF50 promoter. SMARCB1 has also been recognized to be a tumor suppressor protein which controls many tumorigenic events associated with the hedgehog (hh) signaling pathway. We also observed that LXA4 treatment reduces PD-L1 expression and that PD-L1 expression is an important immune evasion strategy used by KSHV for its survival and maintenance in the host. Our study underscores the role of LXA4 in KSHV biology and emphasizes that KSHV is strategic in downregulating LXA4 secretion in the host to establish latency. This study also uncovers the therapeutic potential of LXA4 and its targetable receptor, AhR, in KSHV's pathogenesis.


Assuntos
Cromatina/fisiologia , Herpesvirus Humano 8/metabolismo , Lipoxinas/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Araquidonato 5-Lipoxigenase/genética , Antígeno B7-H1/metabolismo , Linhagem Celular , Cromatina/metabolismo , Ciclo-Oxigenase 2/metabolismo , Regulação Viral da Expressão Gênica/genética , Proteínas Hedgehog/metabolismo , Herpesvirus Humano 8/patogenicidade , Proteínas Imediatamente Precoces/genética , Lipoxinas/fisiologia , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína SMARCB1/metabolismo , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Transativadores/metabolismo , Latência Viral/genética , Replicação Viral/genética
18.
RSC Adv ; 10(69): 42256-42266, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-35516748

RESUMO

The present study is a comparative account of Fe2O3 based photoelectrodes prepared by two different techniques, namely spray pyrolysis and electrochemical deposition, followed by photoelectrochemical analysis at pH 13 (highly alkaline) and pH 8 (near neutral) in 0.1 M NaOH solution for solar hydrogen generation. The study also investigates the influence of morphology at the semiconductor electrode/electrolyte interface along with quantitative determination of the morphological parameters of the rough electrode surface affecting the photoelectrochemical response using power spectral density analysis. Studies revealed that the Fe2O3 sample (E_100cy) prepared with 100 cycles of electrochemical deposition showed the highest photocurrent density of 2.37 mA cm-2 and 1.18 mA cm-2 at 1 V vs. SCE at pH 13 and 8 respectively. Power spectral density analysis exhibited that E_100cy possesses smallest surface features contributing to the PEC response with a lower cut off length scale of 17.23, upper cut off length scale of 150.45, maximum fractal dimension of 2.62 and maximum average rms roughness of 17.52 nm, offering the maximum surface area for charge transfer reactions at the electrode/electrolyte interface. The sample E_100cy exhibited the highest ABPE of 1.29% and IPCE of 37.5%.

19.
J Virol ; 93(9)2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30787155

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV)-induced activation of nuclear factor erythroid 2-related factor 2 (Nrf2) is essential for both the expression of viral genes (latency) and modulation of the host antioxidant machinery. Reactive oxygen species (ROS) are also regulated by the ubiquitously expressed HACE1 protein (HECT domain and ankyrin repeat containing E3 ubiquitin protein ligase 1), which targets the Rac1 protein for proteasomal degradation, and this blocks the generation of ROS by Rac1-dependent NADPH oxidases. In this study, we examined the role of HACE1 in KSHV infection. Elevated levels of HACE1 expression were observed in de novo KSHV-infected endothelial cells, KSHV latently infected TIVE-LTC and PEL cells, and Kaposi's sarcoma skin lesion cells. The increased HACE1 expression in the infected cells was mediated by KSHV latent protein kaposin A. HACE1 knockdown resulted in high Rac1 and Nox 1 (NADPH oxidase 1) activity, increased ROS (oxidative stress), increased cell death, and decreased KSHV gene expression. Loss of HACE1 impaired KSHV infection-induced phosphoinositide 3-kinase (PI3-K), protein kinase C-ζ (PKC-ζ), extracellular signal-regulated kinase 1/2 (ERK1/2), NF-κB, and Nrf2 activation and nuclear translocation of Nrf2, and it reduced the expression of Nrf2 target genes responsible for balancing the oxidative stress. In the absence of HACE1, glutamine uptake increased in the cells to cope with the KSHV-induced oxidative stress. These findings reveal for the first time that HACE1 plays roles during viral infection-induced oxidative stress and demonstrate that HACE1 facilitates resistance to KSHV infection-induced oxidative stress by promoting Nrf2 activity. Our studies suggest that HACE1 could be a potential target to induce cell death in KSHV-infected cells and to manage KSHV infections.IMPORTANCE ROS play important roles in several cellular processes, and increased ROS cause several adverse effects. KSHV infection of endothelial cells induces ROS, which facilitate virus entry by amplifying the infection-induced host cell signaling cascade, which, in turn, induces the nuclear translocation of phospho-Nrf2 protein to regulate the expression of antioxidative genes and viral genes. The present study demonstrates that KSHV infection induces the E3 ligase HACE1 protein to regulate KSHV-induced oxidative stress by promoting the activation of Nrf2 and nuclear translocation. Absence of HACE1 results in increased ROS and cellular death and reduced nuclear Nrf2, antioxidant, and viral gene expression. Together, these studies suggest that HACE1 can be a potential target to induce cell death in KSHV-infected cells.


Assuntos
Células Endoteliais/metabolismo , Infecções por Herpesviridae/metabolismo , Herpesvirus Humano 8/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Ubiquitina-Proteína Ligases/biossíntese , Linhagem Celular , Células Endoteliais/patologia , Células Endoteliais/virologia , Regulação Enzimológica da Expressão Gênica , Regulação Viral da Expressão Gênica , Infecções por Herpesviridae/genética , Herpesvirus Humano 8/genética , Humanos , NADPH Oxidase 1/genética , NADPH Oxidase 1/metabolismo , Fator 2 Relacionado a NF-E2/genética , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Ubiquitina-Proteína Ligases/genética , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo
20.
J Clin Med ; 8(2)2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30764577

RESUMO

Influenza viruses, since time immemorial, have been the major respiratory pathogen known to infect a wide variety of animals, birds and reptiles with established lineages. They belong to the family Orthomyxoviridae and cause acute respiratory illness often during local outbreaks or seasonal epidemics and occasionally during pandemics. Recent studies have identified a new genus within the Orthomyxoviridae family. This newly identified pathogen, D/swine/Oklahoma/1334/2011 (D/OK), first identified in pigs with influenza-like illness was classified as the influenza D virus (IDV) which is distantly related to the previously characterized human influenza C virus. Several other back-to-back studies soon suggested cattle as the natural reservoir and possible involvement of IDV in the bovine respiratory disease complex was established. Not much is known about its likelihood to cause disease in humans, but it definitely poses a potential threat as an emerging pathogen in cattle-workers. Here, we review the evolution, epidemiology, virology and pathobiology of influenza D virus and the possibility of transmission among various hosts and potential to cause human disease.

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