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Gurriny Yealamucka Health Service Aboriginal Corporation (GYHSAC) is an Indigenous community-controlled health organisation providing comprehensive primary care to the people of Yarrabah in far north Queensland, Australia. GYHSAC conducts an annual Young Person's Health Check (YPC) for people aged 15-25 years based on the Medical Benefits Schedule Item 715. However, the YPC is constantly evolving to meet the needs of the community, and in 2016, in response to concerns about psychological risk among Indigenous youth, GYHSAC teamed up with James Cook University to trial an adapted PHQ-9 depression screening tool (aPHQ-9) as part of the YPC. This study describes the 2016 YPC event, reports the prevalence of depressive symptoms, examines local issues related to the use of the screening tool and proposes recommendations for future health screening. Experienced health professionals conducted the aPHQ-9 assessment in a private area of the clinic. One-in-five young people were found to have moderate-severe symptoms or self-harm ideation in the previous 2 weeks; they were referred to the mental health service. The aPHQ-9 screening process was found to be straightforward and well accepted by staff and youth. Importantly, it provided valuable 'space' to facilitate communication on sensitive issues and was a conduit for speedy referral and follow up by trained staff. Based on our experience, we recommend dedicated depression screening in future routine community health checks for young people and adults.
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Traditional vaccine strategies are inefficient against challenge with complex pathogens including HIV; therefore, novel vaccine technologies are required. DNA vaccines are attractive as they are relatively cheap and easy to manufacture, but a major limitation has been their lack of immunogenicity in humans, which may be overcome with the incorporation of an adjuvant. HSP70 is a recognised damage-associated molecular pattern, which is a potential adjuvant. We investigated the immunogenicity of a DNA vaccine encoding HIV gag and HSP70; the latter was genetically modified to produce cytoplasmic, secreted or membrane-bound HSP70, the expression of which was controlled by an independent promoter. The DNA was administered to C57BL/6 mice to evaluate gag-specific T-cell responses. Our results demonstrated the ability of membrane-bound and secreted HSP70 to significantly enhance gag-specific T-cell responses and increase the breadth of T-cell responses to include subdominant epitopes. Membrane-bound or secreted HSP70 also significantly improved the multifunctionality of HIV-specific T cells and T-cell proliferation, which is important for maintaining T-cell integrity. Most importantly, the inclusion of membrane-bound HSP70, secreted HSP70 or a combination significantly increased protection in mice challenged with EcoHIV, a chimeric virus that replicates in mouse leukocytes in vivo.
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Vacinas contra a AIDS/imunologia , Proteínas de Choque Térmico HSP70/imunologia , Vacinas de DNA/imunologia , Animais , Células Dendríticas/fisiologia , Feminino , Células HEK293 , Proteínas de Choque Térmico HSP70/genética , Humanos , Interferon gama/biossíntese , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Linfócitos T/imunologia , Vacinação , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologiaRESUMO
The failure of traditional protein-based vaccines to prevent infection by viruses such as HIV or hepatitis C highlights the need for novel vaccine strategies. DNA vaccines have shown promise in small animal models, and are effective at generating anti-viral T cell-mediated immune responses; however, they have proved to be poorly immunogenic in clinical trials. We propose that the induction of necrosis will enhance the immune response to vaccine antigens encoded by DNA vaccines, as necrotic cells are known to release a range of intracellular factors that lead to dendritic cell (DC) activation and enhanced cross-presentation of antigen. Here we provide evidence that induction of cell death in DNA vaccine-targeted cells provides an adjuvant effect following intradermal vaccination of mice; however, this enhancement of the immune response is dependent on both the mechanism and timing of cell death after antigen expression. We report that a DNA vaccine encoding the cytolytic protein, perforin, resulted in DC activation, enhanced broad and multifunctional CD8 T-cell responses to the HIV-1 antigen GAG and reduced viral load following challenge with a chimeric virus, EcoHIV, compared with the canonical GAG DNA vaccine. This effect was not observed for a DNA vaccine encoding an apoptosis-inducing toxin, DTa, or when the level of perforin expression was increased to induce cell death sooner after vaccination. Thus, inducing lytic cell death following a threshold level of expression of a viral antigen can improve the immunogenicity of DNA vaccines, whereas apoptotic cell death has an inhibitory effect on the immune response.
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Antígenos Virais/imunologia , Imunidade , Perforina/metabolismo , Vacinas de DNA/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Morte Celular , Rastreamento de Células , Células Dendríticas/imunologia , ELISPOT , Citometria de Fluxo , Células HEK293 , Infecções por HIV/imunologia , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/imunologia , Humanos , Injeções Intradérmicas , Interferon gama/metabolismo , Luciferases/metabolismo , Camundongos Endogâmicos C57BL , Vacinação , Carga Viral/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologiaRESUMO
The bovine respiratory disease complex (BRDC) is caused by a variety of pathogens, as well as contributing environmental and host-related risk factors. BRDC is the costliest disease for feedlot cattle globally. Immunohistochemistry (IHC) is a valuable tool for enhancing our understanding of BRDC given its specificity, sensitivity, cost-effectiveness, and capacity to provide information on antigen localization and immune response. Emerging trends in IHC include the use of multiplex IHC for the detection of coinfections, the use of digital imaging and automation, improved detection systems using enhanced fluorescent dyes, and the integration of IHC with spatial transcriptomics. Overall, identifying biomarkers for early detection, utilizing high-throughput IHC for large-scale studies, developing standardized protocols and reagents, and integrating IHC with other technologies are some of the opportunities to enhance the accuracy and applicability of IHC. We summarize here the various techniques and protocols used in IHC and highlight their current and potential role in BRDC research.
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Complexo Respiratório Bovino , Doenças dos Bovinos , Coinfecção , Bovinos , Animais , Imuno-Histoquímica , Complexo Respiratório Bovino/diagnóstico , Fatores de Risco , Coinfecção/veterinária , Doenças dos Bovinos/diagnósticoRESUMO
Bovine parainfluenza-3 virus (BPI3V) is an important respiratory pathogen in cattle, contributing to syndromes in the bovine respiratory disease complex (BRDC). Despite its significance, the understanding of its prevalence remains fragmented, especially within the larger framework of BRDC. This systematic review and meta-analysis aimed to determine the global prevalence of BPI3V in cattle using varied detection methods and to highlight associated risk factors. Of 2187 initially retrieved articles, 71 were selected for analysis, covering 32 countries. Depending on the detection method employed, the meta-analysis revealed significant variations in BPI3V prevalence. In the general cattle population, the highest prevalence was observed using the antibody detection method, with a proportion of 0.64. In contrast, in cattle with BRDC, a prevalence of 0.75 was observed. For the antigen detection method, a prevalence of 0.15 was observed, exclusively in cattle with BRDC. In nucleic acid detection, a prevalence of 0.05 or 0.10 was observed in the general and BRDC cattle populations, respectively. In virus isolation methods, a prevalence of 0.05 or 0.04 was observed in the general and BRDC cattle populations, respectively. These findings highlight the differences in the detection ability of different methods in identifying BPI3V. Other factors, such as country, study year, coinfections, farm size, the presence of respiratory signs, sex, and body weight, may also affect the prevalence. Most studies were anchored within broader BRDC investigations or aimed at detecting other diseases, indicating a potential under-representation of focused BPI3V research. BPI3V plays an important role in BRDC, with its prevalence varying significantly based on the detection methodology. To further understand its unique role within BRDC and pave the way for targeted interventions, there is an evident need for independent, dedicated research on BPI3V.
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Infectious diseases of cattle, including bovine viral diarrhea (BVD), pose a significant health threat to the global livestock industry. This study aimed to investigate the prevalence and risk factors associated with bovine viral diarrhea virus (BVDV) infections in cattle populations through a systematic review and meta-analysis. PubMed, Web of Science, and Scopus were systematically searched for relevant articles reporting the prevalence of and associated risk factors in studies published between 1 January 2000 and 3 February 2023. From a total of 5111 studies screened, 318 studies were included in the final analysis. BVDV prevalence in cattle populations was estimated using various detection methods. The analysis detected heterogeneity in prevalence, attributed to detection techniques and associated risk factors. Antibody detection methods exhibited a higher prevalence of 0.43, reflecting the cumulative effect of detecting both active and past infections. Antigen detection methods showed a prevalence of 0.05, which was lower than antibody methods. A prevalence of 0.08 was observed using nucleic acid detection methods. The health status of the examined cattle significantly influenced the prevalence of BVDV. Cattle with bovine respiratory disease complex (BRDC) exhibited higher antibody (prevalence of 0.67) and antigen (prevalence 0.23) levels compared to cattle with reproductive problems (prevalence 0.13) or diarrhea (prevalence 0.01). Nucleic acid detection methods demonstrated consistent rates across different health conditions. Age of cattle influenced prevalence, with higher rates in adults compared to calves. Risk factors related to breeding and reproduction, such as natural or extensive breeding and a history of abortion, were associated with increased prevalence. Coinfections with pathogens like bovine herpesvirus-1 or Neospora caninum were linked to higher BVDV prevalence. Management practices, such as commingling, introducing new cattle, and direct contact with neighboring farms, also influenced prevalence. Herd attributes, including larger herd size, and the presence of persistently infected cattle, were associated with higher prevalence. These findings indicated the importance of detection methods and risk factors in BVDV epidemiological studies.
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Conventional intensity imaging through turbid media suffers from rapid loss of image contrast due to light scattering from particles or random variations of refractive index. This paper features the development of an active imaging, snapshot, system design and postprocessing algorithms that differentiate between radiation that scatters or reflects from remote, obscured objects and the radiation from the scattering media itself through a combination of polarization difference imaging, channel blurring, and Fourier spatial filtering. The produced sensor acquires and processes image data in real time, yielding improved image contrasts by factors of 10 or greater for dense water vapor obscurants.
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A universal influenza vaccine that does not require annual reformulation would have clear advantages over the currently approved seasonal vaccine. In this study, we combined the mucosal adjuvant alpha-galactosylceramide (αGalCer) and peptides designed across the highly conserved influenza precursor haemagglutinin (HA(0)) cleavage loop as a vaccine. Peptides designed across the HA(0) of influenza A/H3N2 viruses, delivered to mice via the intranasal route with αGalCer as an adjuvant, provided 100â% protection following H3N2 virus challenge. Similarly, intranasal inoculation of peptides across the HA(0) of influenza A/H5N1 with αGalCer completely protected mice against heterotypic challenge with H3N2 virus. Our data suggest that these peptide vaccines effectively inhibited subsequent influenza A/H3N2 virus replication. In contrast, only 20â% of mice vaccinated with αGalCer-adjuvanted peptides spanning the HA(0) of H5N1 survived homologous viral challenge, possibly because the HA(0) of this virus subtype is cleaved by intracellular furin-like enzymes. Results of these studies demonstrated that HA(0) peptides adjuvanted with αGalCer have the potential to form the basis of a synthetic, intranasal influenza vaccine.
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Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vacinas contra Influenza/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Peso Corporal , Proteção Cruzada , Feminino , Galactosilceramidas/administração & dosagem , Glicoproteínas de Hemaglutininação de Vírus da Influenza/administração & dosagem , Histocitoquímica , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/imunologia , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/administração & dosagem , Pulmão/patologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Microscopia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/prevenção & controle , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia , Carga ViralRESUMO
BACKGROUND: Persistent airway gene expression can be achieved in mouse nasal airway using a vesicular stomatitis virus glycoprotein pseudotyped lentiviral (LV) gene vector in combination with lysophosphatidylcholine (LPC) pretreatment. We have now examined the acute in vivo effects of this combination single-dose method for airway LV gene transfer in mouse and sheep lung. METHODS: Mouse and sheep lungs were exposed to LPC followed 1 h later with the LV vector. Lungs were processed 7 days later using X-gal detection to measure beta-gal gene expression and identify transduced cell types. RESULTS: In mouse ciliated conducting airways, LPC pretreatment produced extensive gene transfer that extended from the tracheal dosing site into the bronchi and lower airways. Gene expression was present in both terminally differentiated surface cells and in basal cells. Without LPC pretreatment, transduction was limited to the dosing site. In sheep lung, small-volume bronchoscopic instillation delivery produced localized and low-level transduction near the dosing site. Gene expression was again present in surface and basal cells. Neither alterations in LPC dose parameters, nor larger vector volumes increased the level of transduction. CONCLUSIONS: These findings are the first to confirm the applicability of LPC pretreatment in the production of extensive lentiviral gene transfer in mouse lung airways. However, improved methodologies to increase transduction efficiency are required for adult sheep lung. The results suggest that continued in vivo development of LPC-enhanced lentiviral gene transfer is needed in the lungs of large animals to establish effective lentiviral gene transfer techniques suited to the treatment of airway disease.
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Vetores Genéticos , Lentivirus/genética , Pulmão/metabolismo , Transdução Genética , Animais , Feminino , Expressão Gênica , Terapia Genética , Lisofosfatidilcolinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Sistema Respiratório/metabolismo , OvinosRESUMO
BACKGROUND: Cystic fibrosis (CF) is caused by a defect in cystic fibrosis transmembrane conductance regulator (CFTR) activity, often resulting in an incurable airway disease. Gene therapy into the conducting airway epithelium is a potential cure for CF; however, most gene vectors do not result in long-lived expression, and require re-dosing. Perversely, intrinsic host immune responses can then block renewed gene transfer. METHODS: To investigate whether persistent gene expression could be achieved after a single dosing event, thus avoiding the issue of blocking host responses, we used a gene transfer protocol that combined an airway pretreatment using lysophosphatidylcholine with a human immunodeficiency virus type-1 (vesicular stomatitis virus G pseudotype) derived lentiviral vector to test whether an integrating vector could produce gene expression able to last for a substantial part of the lifetime of the laboratory mouse. RESULTS: We found that a single dose of LV-LacZ produced immediate as well as lifetime mouse airway expression, confirming our hypothesis that use of an integrating vector extends transgene expression. Importantly, LV-CFTR dosing achieved at least 12 months of CFTR expression, representing partial functional correction of the CFTR defect in CF-null mice. CONCLUSIONS: These findings validate the potential of this methodology for developing a gene transfer treatment for CF airway disease.
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Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fibrose Cística/terapia , Técnicas de Transferência de Genes , Vetores Genéticos/administração & dosagem , Vetores Genéticos/metabolismo , Lentivirus/genética , Mucosa Respiratória/metabolismo , Animais , Linhagem Celular , Fibrose Cística/genética , Fibrose Cística/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Expressão Gênica , Terapia Genética/métodos , Vetores Genéticos/genética , HIV-1/genética , Humanos , Lisofosfatidilcolinas/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CFTR , Mucosa Respiratória/efeitos dos fármacos , Fatores de TempoRESUMO
Intensive pine (Pinus spp.) management is a primary land use in the southeastern United States. In eastern North Carolina, intensively managed pine stands often occur on land previously ditched and drained. Because modification of natural vegetation and water sources are known to affect dipteran community structure, we studied effects of intensive pine management on abundance and diversity of dipteran families in the northern coastal plain of North Carolina during 2006 and 2007. We used malaise traps and emergence traps to sample different types of forest stands (n = 143 sample nights) and water sources (n = 147 sample nights) in a managed pine forest and a natural forested wetland. Cecidomyiids were more abundant in stands with canopy cover, chironomids were more abundant at edges between forested stands and open canopy stands, and chloropids were more abundant in open canopy stands. Families Ceratopogonidae, Dolichopodidae, Ephydridae, Muscidae, Psychodidae, and Tipulidae were more abundant in the natural forested wetland than in all types of modified water sources. Dipteran diversity and evenness were highest in stands with open canopy and at forest edges, and highest in the natural forested wetland. Unmanaged, natural stands on the intensively managed landscape did not support a higher abundance or diversity of dipteran families than intensively managed stands. Restoration of natural wetlands may increase dipteran diversity in unmanaged stands. Heliponds, a modified water source, supported a comparable dipteran abundance to that of the natural forested wetland. Increased numbers of heliponds may facilitate higher dipteran abundance in managed pine landscapes.
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Biodiversidade , Dípteros , Agricultura Florestal , Pinus taeda , Áreas Alagadas , Animais , Água Doce , North CarolinaRESUMO
Reactive oxygen species-induced oxidative damage remains an extensively validated secondary injury mechanism in traumatic brain injury (TBI) as demonstrated by the efficacy of various pharmacological antioxidants agents in decreasing post-traumatic free radical-induced lipid peroxidation (LP) and protein oxidative damage in preclinical TBI models. Based upon strong preclinical efficacy results, two antioxidant agents, the superoxide radical scavenger polyethylene glycol-conjugated superoxide dismutase (PEG-SOD) and the 21-aminosteroid LP inhibitor tirilazad, which inhibits lipid peroxidation, (LP) were evaluated in large phase III trials in moderately- and severely-injured TBI patients. Both failed to improve 6 month survival and neurological recovery. However, in the case of tirilazad, a post hoc analysis revealed that the drug significantly improved survival of male TBI patients who exhibited traumatic subarachnoid hemorrhage (tSAH) that occurs in half of severe TBIs. In addition to reviewing the clinical trial results with PEG-SOD and tirilazad, newer antioxidant approaches which appear to improve neuroprotective efficacy and provide a longer therapeutic window in rodent TBI models will be presented. The first approach involves pharmacological enhancement of the multi-mechanistic Nrf2-antioxidant response element (ARE) pathway. The second involves scavenging of the neurotoxic LP-derived carbonyl compounds 4-hydroxynonenal (4-HNE) and acrolein which are highly damaging to neural protein and stimulate additional free radical generation. A third approach combines mechanistically complimentary antioxidants to interrupt post-TBI oxidative neurodegeneration at multiple points in the secondary injury cascade. These newer strategies appear to decrease variability in the neuroprotective effect which should improve the feasibility of achieving successful translation of antioxidant therapy to TBI patients.
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Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Animais , HumanosRESUMO
PURPOSE: Koala retrovirus (KoRV-A) is 100 â% prevalent in northern Australian (Queensland and New South Wales) koala populations, where KoRV-B has been associated with Chlamydia pecorum disease and the development of lymphosarcoma. In southern populations (Victoria and South Australia), KoRV-A is less prevalent and KoRV-B has not been detected in Victoria, while the current prevalence in South Australian populations is unknown but is thought to be low. This study aimed to determine (i) the prevalence of KoRV in the two largest South Australian koala populations [Kangaroo Island (KI) and Mount Lofty Ranges (MLR)], (ii) KoRV subtype and (iii) if an association between KoRV and C. pecorum exists. METHODOLOGY: Wild koalas were sampled in KI ( n =170) between 2014 and 2017 and in MLR ( n =75) in 2016. Clinical examinations were performed, with blood collected for KoRV detection and typing by PCR. RESULTS: KoRV prevalence was 42.4 â% [72/170, 95 % confidence interval (CI): 34.9-49.8 â%] in KI and 65.3 â% (49/75, 95 % CI: 54.6-76.1 â%) in MLR. Only KoRV-A, and not KoRV-B, was detected in both populations. In MLR, there was no statistical association between KoRV and C. pecorum infection (P =0.740), or KoRV and C. pecorum disease status ( P=0.274), although KoRV-infected koalas were more likely to present with overt C. pecorum disease than subclinical infection (odds ratio: 3.15, 95â% CI: 0.91-5.39). CONCLUSION: KoRV-A is a prevalent pathogen in wild South Australian koala populations. Future studies should continue to investigate KoRV and C. pecorum associations, as the relationship is likely to be complex and to differ between the northern and southern populations.
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Phascolarctidae/virologia , Infecções por Retroviridae/veterinária , Retroviridae/genética , Envelhecimento , Animais , Chlamydia/classificação , Chlamydia/isolamento & purificação , Infecções por Chlamydia/complicações , Infecções por Chlamydia/veterinária , DNA Viral/genética , Feminino , Genótipo , Masculino , Razão de Chances , Prevalência , Retroviridae/isolamento & purificação , Infecções por Retroviridae/complicações , Infecções por Retroviridae/epidemiologia , Infecções por Retroviridae/virologia , Fatores de Risco , Austrália do Sul/epidemiologiaRESUMO
Recent evidence has demonstrated that treatment with progesterone can attenuate many of the pathophysiological events following traumatic brain injury (TBI) in young adult rats, but this effect has not been investigated in aged animals. In this study, 20-month-old male Fischer 344 rats with bilateral contusions of the frontal cortex (n = 4 per group) or sham operations received 8, 16, or 32 mg/kg of progesterone or vehicle. Locomotor activity was measured at 72 h to assess behavioral recovery. Brain tissue was harvested at 24, 48, and 72 h, and Western blotting was performed for inflammatory and apoptotic factors. Edema was assessed at 48 h by measuring brain water content. Injured animals treated with 8 and 16 mg/kg progesterone showed decreased expression of COX-2, IL-6, and NFkappaB at all time points, indicating a reduction in the acute inflammatory process compared to vehicle. The 16 mg/kg group also showed reduced apoptosis at all time points as well as decreased edema and improved locomotor outcomes. Thus, in aged male rats, treatment with 16 mg/kg progesterone improves short-term motor recovery and attenuates edema, secondary inflammation, and cell death after TBI.
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Lesões Encefálicas/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Progesterona/uso terapêutico , Progestinas/uso terapêutico , Recuperação de Função Fisiológica/efeitos dos fármacos , Fatores Etários , Animais , Apoptose/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Western Blotting , Edema Encefálico/tratamento farmacológico , Edema Encefálico/patologia , Lesões Encefálicas/patologia , Citocinas/biossíntese , Citocinas/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344RESUMO
Intensively-managed pine (Pinus spp.) have been shown to support diverse vertebrate communities, but their ability to support invertebrate communities, such as wild bees, has not been well-studied. Recently, researchers have examined intercropping switchgrass (Panicum virgatum), a native perennial, within intensively managed loblolly pine (P. taeda) plantations as a potential source for cellulosic biofuels. To better understand potential effects of intercropping on bee communities, we investigated visitation of bees within three replicates of four treatments of loblolly pine in Mississippi, U.S.A.: 3-4 year old pine plantations and 9-10 year old pine plantations with and without intercropped switchgrass. We used colored pan traps to capture bees during the growing seasons of 2013 and 2014. We captured 2507 bees comprised of 18 different genera during the two-year study, with Lasioglossum and Ceratina being the most common genera captured. Overall, bee abundances were dependent on plantation age and not presence of intercropping. Our data suggests that switchgrass does not negatively impact or promote bee communities within intensively-managed loblolly pine plantations.
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The importance of free radical-induced oxidative damage after traumatic brain injury (TBI) has been well documented. Despite multiple clinical trials with radical-scavenging antioxidants that are neuroprotective in TBI models, none is approved for acute TBI patients. As an alternative antioxidant target, Nrf2 is a transcription factor that activates expression of antioxidant and cytoprotective genes by binding to antioxidant response elements (AREs) within DNA. Previous research has shown that neuronal mitochondria are susceptible to oxidative damage post-TBI, and thus the current study investigates whether Nrf2-ARE activation protects mitochondrial function when activated post-TBI. It was hypothesized that administration of carnosic acid (CA) would reduce oxidative damage biomarkers in the brain tissue and also preserve cortical mitochondrial respiratory function post-TBI. A mouse controlled cortical impact (CCI) model was employed with a 1.0mm cortical deformation injury. Administration of CA at 15 min post-TBI reduced cortical lipid peroxidation, protein nitration, and cytoskeletal breakdown markers in a dose-dependent manner at 48 h post-injury. Moreover, CA preserved mitochondrial respiratory function compared to vehicle animals. This was accompanied by decreased oxidative damage to mitochondrial proteins, suggesting the mechanistic connection of the two effects. Lastly, delaying the initial administration of CA up to 8h post-TBI was still capable of reducing cytoskeletal breakdown, thereby demonstrating a clinically relevant therapeutic window for this approach. This study demonstrates that pharmacological Nrf2-ARE induction is capable of neuroprotective efficacy when administered after TBI.
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Abietanos/uso terapêutico , Antioxidantes/uso terapêutico , Lesões Encefálicas/complicações , Citoesqueleto/metabolismo , Doenças Mitocondriais/tratamento farmacológico , Doenças Mitocondriais/etiologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Difosfato de Adenosina/metabolismo , Aldeídos/metabolismo , Análise de Variância , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Lesões Encefálicas/tratamento farmacológico , Citoesqueleto/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Ácido Succínico/metabolismoRESUMO
Understanding the ecology of the gastrointestinal tract and the impact of the contents on the host mucosa is emerging as an important area for defining both wellness and susceptibility to disease. Targeted delivery of drugs to treat specific small intestinal disorders such as small bowel bacterial overgrowth and targeting molecules to interrogate or to deliver vaccines to the remote regions of the small intestine has proven difficult. There is an unmet need for methodologies to release probes/drugs to remote regions of the gastrointestinal tract in furthering our understanding of gut health and pathogenesis. In order to address this concern, we need to know how the regional delivery of a surrogate labeled test compound is handled and in turn, if delivered locally as a liquid or powder, the dynamics of its subsequent handling and metabolism. In the studies we report on in this paper, we chose (13)C sodium acetate ((13)C-acetate), which is a stable isotope probe that once absorbed in the small intestine can be readily measured non-invasively by collection and analysis of (13)CO2 in the breath. This would provide information of gastric emptying rates and an indication of the site of release and absorptive capacity. In a series of in vitro and in vivo pig experiments, we assessed the enteric-protective properties of a commercially available polymer EUDRAGIT(®) L100-55 on gelatin capsules and also on DRcaps(®). Test results demonstrated that DRcaps(®) coated with EUDRAGIT(®) L100-55 possessed enhanced enteric-protective properties, particularly in vivo. These studies add to the body of knowledge regarding gastric emptying in pigs and also begin the process of gathering specifications for the design of a simple and cost-effective enteric-coated capsule for delivery of acid-labile macromolecules to the small intestine.
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Ácidos e Sais Biliares/química , Cápsulas/síntese química , Cápsulas/farmacocinética , Absorção Intestinal/fisiologia , Substâncias Macromoleculares/farmacocinética , Ácidos Polimetacrílicos/química , Administração Oral , Animais , Materiais Revestidos Biocompatíveis/química , Composição de Medicamentos/métodos , Feminino , Substâncias Macromoleculares/administração & dosagem , SuínosRESUMO
The pathophysiological importance of oxidative damage after traumatic brain injury (TBI) has been extensively demonstrated. The transcription factor nuclear factor erythoid related factor 2 (Nrf2) mediates antioxidant and cytoprotective genes by binding to antioxidant response elements (ARE) present in nuclear DNA. In this study, we characterized the time course of Nrf2-ARE-mediated expression in the cortex and hippocampus using a unilateral controlled cortical impact model of focal TBI. Ipsilateral hippocampal and cortical tissue was collected for Western-blot protein analysis (n=6/group) or quantitative reverse transcription-polymerase chain reaction for mRNA (n=3/group) at 3, 6, 12, 24, 48, and 72 h or 1 week post-injury. Multiple genes mediated by Nrf2-ARE were altered post-TBI. Specifically, Nrf2 mRNA increased significantly post-TBI at 48 and 72 h in the cortex and at 48 and 72 h and 1 week in the hippocampus with a coincident increase in glial fibrillary acidic protein mRNA, thereby implying this response is likely occurring in astrocytes. Presumably linked to Nrf2 activation, heme-oxygenase-1, nicotinamide adenine dinucleotide phosphate-quinone-oxidoreductase 1, glutathione reductase, and catalase mRNA overlap throughout the post-injury time course. This study demonstrates the first evidence of such changes during the first week after focal TBI and that increases in expression of some Nrf2-ARE-mediated cytoprotective genes are not observed until 24-48 h post-injury. Unfortunately, this does not precede, but rather coincides with, the occurrence of lipid peroxidative damage. This is the first known comparison between the time course of peroxidative damage and that of Nrf2-ARE activation during the first week post-TBI. These results underscore the necessity to discover pharmacological agents to accelerate and amplify Nrf2-ARE-mediated expression early post-TBI.
Assuntos
Elementos de Resposta Antioxidante/fisiologia , Lesões Encefálicas/metabolismo , Córtex Cerebral/metabolismo , Marcação de Genes , Hipocampo/metabolismo , Fator 2 Relacionado a NF-E2/biossíntese , Animais , Lesões Encefálicas/patologia , Córtex Cerebral/patologia , Marcação de Genes/métodos , Hipocampo/patologia , Peroxidação de Lipídeos/fisiologia , Masculino , Camundongos , Fatores de TempoRESUMO
The potential of DNA vaccines has not been realised due to suboptimal delivery, poor antigen expression and the lack of localised inflammation, essential for antigen presentation and an effective immune response to the immunogen. Initially, we examined the delivery of a DNA vaccine encoding a model antigen, luciferase (LUC), to the respiratory tract of mice by encapsulation in a virosome. Virosomes that incorporated influenza virus haemagglutinin effectively delivered DNA to cells in the mouse respiratory tract and resulted in antigen expression and systemic and mucosal immune responses to the immunogen after an intranasal (IN) prime/intradermal (ID) boost regimen, whereas a multidose ID regimen only generated systemic immunity. We also examined systemic immune responses to LUC after ID vaccination with a DNA vaccine, which also encoded one of the several cytolytic or toxic proteins. Although the herpes simplex virus thymidine kinase, in the presence of the prodrug, ganciclovir, resulted in cell death, this failed to increase the humoral or cell-mediated immune responses. In contrast, the co-expression of LUC with the rotavirus non-structural protein 4 (NSP4) protein or a mutant form of mouse perforin, proteins which are directly cytolytic, resulted in increased LUC-specific humoral and cell-mediated immunity. On the other hand, co-expression of LUC with diphtheria toxin subunit A or overexpression of perforin or NSP4 resulted in a lower level of immunity. In summary, the efficacy of DNA vaccines can be improved by targeted IN delivery of DNA or by the induction of cell death in vaccine-targeted cells after ID delivery.
RESUMO
When establishing animal models of viral respiratory infection, the optimal dose and route of delivery are critical to ensure reproducible outcomes. The mouse model for influenza infection is widely used due to the small animal size and simplicity of viral inoculation. During establishment of a mouse model of influenza A infection we observed a marked shift in morbidity when identical influenza A inoculum doses were delivered in less than 35 µL. We show for the first time that mice challenged with a 25 µL inoculum volume readily recovered following infection with an infectious dose of influenza A virus that was fatal when inoculated in 35 or 50 µL volumes.