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1.
J Forensic Sci ; 69(3): 974-985, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38317608

RESUMO

Ethanol is the psychoactive substance identified most frequently in post-mortem specimens. Unfortunately, interpreting post-mortem ethanol concentrations can be difficult because of post-mortem alcohol redistribution and the possibility of post-mortem alcohol neogenesis. Indeed, in the time interval between death and sample collection, the decedent may be exposed to non-controlled environments for an extended period, promoting microbial colonization. Many authors report that in the presence of carbohydrates and other biomolecules, various species of bacteria, yeast, and fungi can synthesize ethanol and other volatile substances in vitro and in vivo. The aim of this study was to study the impact of several variables on microbial ethanol production as well as develop a mathematical model that could estimate the microbial-produced ethanol in correlation with the most significant consensual produced higher alcohol, 1-propanol. An experimental setup was developed using human blood samples and cadaveric fragments incubated under strictly anaerobic conditions to produce a novel substrate, "cadaveric putrefactive blood" mimicking post-mortem corpse conditions. The samples were analyzed daily for ethanol and 1-propanol using an HS-GC-FID validated method. The formation of ethanol was evaluated considering different parameters such as putrefactive stage, blood glucose concentration, storage temperature, and storage time. Statistical analysis was performed using the Mann-Whitney non-parametric test and simple linear regression. The results indicate that the early putrefactive stage, high blood glucose concentration, high temperature, and time of incubation increase microbial ethanol production. In addition, the developed mathematical equation confirms the feasibility of using 1-propanol as a marker of post-mortem ethanol production.


Assuntos
1-Propanol , Etanol , Mudanças Depois da Morte , Estudo de Prova de Conceito , Humanos , Etanol/análise , Manejo de Espécimes , Cromatografia Gasosa , Biomarcadores/análise , Biomarcadores/metabolismo , Depressores do Sistema Nervoso Central/análise , Toxicologia Forense , Concentração Alcoólica no Sangue , Cadáver , Temperatura , Modelos Teóricos , Ionização de Chama
2.
J Neurochem ; 167(2): 277-295, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37702109

RESUMO

Copper is an essential enzyme cofactor in oxidative metabolism, anti-oxidant defenses, and neurotransmitter synthesis. However, intracellular copper, when improperly buffered, can also lead to cell death. Given the growing interest in the use of copper in the presence of the ionophore elesclomol (CuES) for the treatment of gliomas, we investigated the effect of this compound on the surround parenchyma-namely neurons and astrocytes in vitro. Here, we show that astrocytes were highly sensitive to CuES toxicity while neurons were surprisingly resistant, a vulnerability profile that is opposite of what has been described for zinc and other toxins. Bolstering these findings, a human astrocytic cell line was similarly sensitive to CuES. Modifications of cellular metabolic pathways implicated in cuproptosis, a form of copper-regulated cell death, such as inhibition of mitochondrial respiration or knock-down of ferredoxin 1 (FDX1), did not block CuES toxicity to astrocytes. CuES toxicity was also unaffected by inhibitors of apoptosis, necrosis or ferroptosis. However, we did detect the presence of lipid peroxidation products in CuES-treated astrocytes, indicating that oxidative stress is a mediator of CuES-induced glial toxicity. Indeed, treatment with anti-oxidants mitigated CuES-induced cell death in astrocytes indicating that oxidative stress is a mediator of CuES-induced glial toxicity. Lastly, prior induction of metallothioneins 1 and 2 in astrocytes with zinc plus pyrithione was strikingly protective against CuES toxicity. As neurons express high levels of metallothioneins basally, these results may partially account for their resistance to CuES toxicity. These results demonstrate a unique toxic response to copper in glial cells which contrasts with the cell selectivity profile of zinc, another biologically relevant metal.


Assuntos
Cobre , Ferredoxinas , Humanos , Cobre/farmacologia , Ferredoxinas/metabolismo , Ferredoxinas/farmacologia , Astrócitos/metabolismo , Estresse Oxidativo , Antioxidantes/farmacologia , Zinco/farmacologia , Neurônios/metabolismo , Células Cultivadas
3.
Redox Biol ; 63: 102727, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37156218

RESUMO

Adipose plasticity is critical for metabolic homeostasis. Adipocyte transdifferentiation plays an important role in adipose plasticity, but the molecular mechanism of transdifferentiation remains incompletely understood. Here we show that the transcription factor FoxO1 regulates adipose transdifferentiation by mediating Tgfß1 signaling pathway. Tgfß1 treatment induced whitening phenotype in beige adipocytes, reducing UCP1 and mitochondrial capacity and enlarging lipid droplets. Deletion of adipose FoxO1 (adO1KO) dampened Tgfß1 signaling by downregulating Tgfbr2 and Smad3 and induced browning of adipose tissue in mice, increasing UCP1 and mitochondrial content and activating metabolic pathways. Silencing FoxO1 also abolished the whitening effect of Tgfß1 on beige adipocytes. The adO1KO mice exhibited a significantly higher energy expenditure, lower fat mass, and smaller adipocytes than the control mice. The browning phenotype in adO1KO mice was associated with an increased iron content in adipose tissue, concurrent with upregulation of proteins that facilitate iron uptake (DMT1 and TfR1) and iron import into mitochondria (Mfrn1). Analysis of hepatic and serum iron along with hepatic iron-regulatory proteins (ferritin and ferroportin) in the adO1KO mice revealed an adipose tissue-liver crosstalk that meets the increased iron requirement for adipose browning. The FoxO1-Tgfß1 signaling cascade also underlay adipose browning induced by ß3-AR agonist CL316243. Our study provides the first evidence of a FoxO1-Tgfß1 axis in the regulation of adipose browning-whitening transdifferentiation and iron influx, which sheds light on the compromised adipose plasticity in conditions of dysregulated FoxO1 and Tgfß1 signaling.


Assuntos
Tecido Adiposo Marrom , Transdiferenciação Celular , Camundongos , Animais , Tecido Adiposo Marrom/metabolismo , Ferro/metabolismo , Obesidade/genética , Obesidade/metabolismo , Transdução de Sinais , Tecido Adiposo Branco/metabolismo , Camundongos Endogâmicos C57BL , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo
4.
J Hepatol ; 78(5): 937-946, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36669704

RESUMO

BACKGROUND & AIMS: HCV test and treat campaigns currently exclude pregnant women. Pregnancy offers a unique opportunity for HCV screening and to potentially initiate direct-acting antiviral treatment. We explored HCV screening and treatment strategies in two lower middle-income countries with high HCV prevalence, Egypt and Ukraine. METHODS: Country-specific probabilistic decision models were developed to simulate a cohort of pregnant women. We compared five strategies: S0, targeted risk-based screening and deferred treatment (DT) to after pregnancy/breastfeeding; S1, World Health Organization (WHO) risk-based screening and DT; S2, WHO risk-based screening and targeted treatment (treat women with risk factors for HCV vertical transmission [VT]); S3, universal screening and targeted treatment during pregnancy; S4, universal screening and treatment. Maternal and infant HCV outcomes were projected. RESULTS: S0 resulted in the highest proportion of women undiagnosed: 59% and 20% in Egypt and Ukraine, respectively, with 0% maternal cure by delivery and VT estimated at 6.5% and 7.9%, respectively. WHO risk-based screening and DT (S1) increased the proportion of women diagnosed with no change in maternal cure or VT. Universal screening and treatment during pregnancy (S4) resulted in the highest proportion of women diagnosed and cured by delivery (65% and 70%, respectively), and lower levels of VT (3.4% and 3.6%, respectively). CONCLUSIONS: This is one of the first models to explore HCV screening and treatment strategies in pregnancy, which will be critical in informing future care and policy as more safety/efficacy data emerge. Universal screening and treatment in pregnancy could potentially improve both maternal and infant outcomes. IMPACT AND IMPLICATIONS: In the context of two lower middle-income countries with high HCV burdens (Egypt and Ukraine), we designed a decision analytic model to explore five different HCV testing and treatment strategies for pregnant women, with the assumption that treatment was safe and efficacious for use in pregnancy. Assuming direct-acting antiviral treatment during pregnancy would reduce vertical transmission, our findings indicate that the provision of universal (rather than risk-based targeted) screening and treatment would provide the greatest maternal and infant benefits. While future trials are needed to assess the safety and efficacy of direct-acting antivirals in pregnancy and their impact on vertical transmission, there is increasing recognition that the elimination of HCV cannot leave entire subpopulations of pregnant women and young children behind. Our findings will be critical for policymakers when developing improved screening and treatment recommendations for pregnant women.


Assuntos
Hepatite C Crônica , Hepatite C , Complicações Infecciosas na Gravidez , Criança , Humanos , Gravidez , Feminino , Pré-Escolar , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Egito/epidemiologia , Ucrânia/epidemiologia , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia , Programas de Rastreamento , Transmissão Vertical de Doenças Infecciosas/prevenção & controle
5.
Microbiome ; 10(1): 171, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36242064

RESUMO

BACKGROUND: Faecal samples are frequently used to characterise the gut microbiota in health and disease, yet there is considerable debate about how representative faecal bacterial profiles are of the overall gut community. A particular concern is whether bacterial populations associated with the gut mucosa are properly represented in faecal samples, since these communities are considered critical in the aetiology of gastrointestinal diseases. In this study we compared the profiles of the faecal and mucosal microbiota from ten healthy volunteers using bacterial culturing (culturomics) and next-generation sequencing targeting the 16S ribosomal nucleic acid (rRNA) gene. Paired fresh rectal biopsies and faecal samples were processed under stringent anaerobic conditions to maintain the viability of the bacteria. Four different sample types were analysed: faecal (F), faecal homogenised (FHg), biopsy tissue (B) and biopsy wash (BW) samples.  RESULTS: There were no significant statistical differences in either bacterial richness or diversity between biopsy washes (BW) and faecal (F) or faecal homogenised (FHg) samples. Principal coordinates analysis of a Bray-Curtis distance matrix generated from sequence variant tables did not show distinct clustering between these samples (PERMANOVA; p = 0.972) but showed strong clustering of samples from individual donors. However, the rectal biopsy tissue (B) samples had a significantly altered bacterial signature with greater abundance of Proteobacteria and Acidobacteria compared to faecal (F) and faecal homogenised (FHg) samples. A total of 528 bacteria encompassing 92 distinct bacterial species were isolated and cultured from a subset of six volunteer samples (biopsy washes and faeces). This included isolation of 22 novel bacterial species. There was significant similarity between the bacterial species grown in anaerobic culture and those identified by 16S rRNA gene sequencing (Spearman correlation; rho = 0.548, p = 0.001). CONCLUSION: This study showed that the bacterial profiles of paired faecal and rectal biopsy wash samples were very similar, validating the use of faecal samples as a convenient surrogate for rectal biopsy-associated microbiota. Anaerobic bacterial culture results showed similar taxonomic patterns to the amplicon sequence analysis disproving the dogma that culture-based methods do not reflect findings of molecular assessments of gut bacterial composition. Video abstract.


Assuntos
Bactérias , Sequenciamento de Nucleotídeos em Larga Escala , Biópsia , Fezes/microbiologia , Voluntários Saudáveis , Humanos , RNA Ribossômico 16S/genética
6.
Neurooncol Adv ; 4(1): vdac085, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35821679

RESUMO

Background: Brain tumors are the leading cause of cancer death for pediatric patients. Pelareorep, an immunomodulatory oncolytic reovirus, has intravenous efficacy in preclinical glioma models when preconditioned with GM-CSF (sargramostim). We report a phase I trial with the primary goal of evaluating the safety of sargramostim/pelareorep in pediatric patients with recurrent or refractory high-grade brain tumors and a secondary goal of characterizing immunologic responses. Methods: The trial was open to pediatric patients with recurrent or refractory high-grade brain tumors (3 + 3 cohort design). Each cycle included 3 days of subcutaneous sargramostim followed by 2 days of intravenous pelareorep. Laboratory studies and imaging were acquired upon recruitment and periodically thereafter. Results: Six patients participated, including three glioblastoma, two diffuse intrinsic pontine glioma, and one medulloblastoma. Two pelareorep dose levels of 3 × 108 and 5 × 108 tissue culture infectious dose 50 (TCID50) were assessed. One patient experienced a dose limiting toxicity of persistent hyponatremia. Common low-grade (1 or 2) adverse events included transient fatigue, hypocalcemia, fever, flu-like symptoms, thrombocytopenia, and leukopenia. High-grade (3 or 4) adverse events included neutropenia, lymphopenia, leukopenia, hypophosphatemia, depressed level of consciousness, and confusion. All patients progressed on therapy after a median of 32.5 days and died a median of 108 days after recruitment. Imaging at progression did not show evidence of pseudoprogression or inflammation. Correlative assays revealed transient but consistent changes in immune cells across patients. Conclusions: Sargramostim/pelareorep was administered to pediatric patients with recurrent or refractory high-grade brain tumors. Hyponatremia was the only dose limiting toxicity (DLT), though maximum tolerated dose (MTD) was not determined.

7.
Cancers (Basel) ; 14(9)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35565310

RESUMO

Pexa-Vec is an engineered Wyeth-strain vaccinia oncolytic virus (OV), which has been tested extensively in clinical trials, demonstrating enhanced cytotoxic T cell infiltration into tumours following treatment. Favourable immune consequences to Pexa-Vec include the induction of an interferon (IFN) response, followed by inflammatory cytokine/chemokine secretion. This promotes tumour immune infiltration, innate and adaptive immune cell activation and T cell priming, culminating in targeted tumour cell killing, i.e., an immunologically 'cold' tumour microenvironment is transformed into a 'hot' tumour. However, as with all immunotherapies, not all patients respond in a uniformly favourable manner. Our study herein, shows a differential immune response by patients to intravenous Pexa-Vec therapy, whereby some patients responded to the virus in a typical and expected manner, demonstrating a significant IFN induction and subsequent peripheral immune activation. However, other patients experienced a markedly subdued immune response and appeared to exhibit an exhausted phenotype at baseline, characterised by higher baseline immune checkpoint expression and regulatory T cell (Treg) levels. This differential baseline immunological profile accurately predicted the subsequent response to Pexa-Vec and may, therefore, enable the development of predictive biomarkers for Pexa-Vec and OV therapies more widely. If confirmed in larger clinical trials, these immunological biomarkers may enable a personalised approach, whereby patients with an exhausted baseline immune profile are treated with immune checkpoint blockade, with the aim of reversing immune exhaustion, prior to or alongside OV therapy.

8.
Cancer Immunol Res ; 10(6): 745-756, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35439304

RESUMO

Improving the chances of curing patients with cancer who have had surgery to remove metastatic sites of disease is a priority area for cancer research. Pexa-Vec (Pexastimogene Devacirepvec; JX-594, TG6006) is a principally immunotherapeutic oncolytic virus that has reached late-phase clinical trials. We report the results of a single-center, nonrandomized biological end point study (trial registration: EudraCT number 2012-000704-15), which builds on the success of the presurgical intravenous delivery of oncolytic viruses to tumors. Nine patients with either colorectal cancer liver metastases or metastatic melanoma were treated with a single intravenous infusion of Pexa-Vec ahead of planned surgical resection of the metastases. Grade 3 and 4 Pexa-Vec-associated side effects were lymphopaenia and neutropaenia. Pexa-Vec was peripherally carried in plasma and was not associated with peripheral blood mononuclear cells. Upon surgical resection, Pexa-Vec was found in the majority of analyzed tumors. Pexa-Vec therapy associated with IFNα secretion, chemokine induction, and resulted in transient innate and long-lived adaptive anticancer immunity. In the 2 patients with significant and complete tumor necrosis, a reduction in the peripheral T-cell receptor diversity was observed at the time of surgery. These results support the development of presurgical oncolytic vaccinia virus-based therapies to stimulate anticancer immunity and increase the chances to cure patients with cancer.


Assuntos
Neoplasias Hepáticas , Terapia Viral Oncolítica , Vírus Oncolíticos , Humanos , Leucócitos Mononucleares , Neoplasias Hepáticas/terapia , Terapia Neoadjuvante , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/genética , Vaccinia virus/genética
9.
Front Physiol ; 13: 841078, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35399269

RESUMO

The brain maintains cardiovascular homeostasis, in part, via the arterial baroreflex which senses changes in blood pressure (BP) at the level of the aortic arch. Sensory afferents innervating the aortic arch employ baroreceptors to convert stretch exerted on the arterial wall into action potentials carried by the vagus nerve to second order neurons residing within the nucleus of the solitary tract (NTS). Although the baroreflex was described more than 80 years ago, the specific molecular, structural, and functional phenotype of the baroreceptors remain uncharacterized. This is due to the lack of tools that provide the genetic and target organ specificity that is required to selectively characterize baroreceptor afferents. Here, we use a novel approach to selectively target baroreceptors. Male mice on a C57BL/6J background were anesthetized with isoflurane, intubated, and artificially ventilated. Following sternotomy, the aortic arch was exposed, and a retrograde adeno-associated virus was applied to the aortic arch to direct the expression of channelrhoropsin-2 (ChR2) and/or tdTomato (tdTom) to sensory afferents presumably functioning as baroreceptors. Consistent with the structural characteristics of arterial baroreceptors, robust tdTom expression was observed in nerve endings surrounding the aortic arch, within the fibers of the aortic depressor and vagus nerves, cell bodies of the nodose ganglia (NDG), and neural projections to the caudal NTS (cNTS). Additionally, the tdTom labeled cell bodies within the NDG also expressed mRNAs coding for the mechanically gated ion channels, PIEZO-1 and PIEZO-2. In vitro electrophysiology revealed that pulses of blue light evoked excitatory post-synaptic currents in a subset of neurons within the cNTS, suggesting a functional connection between the labeled aortic arch sensory afferents and second order neurons. Finally, the in vivo optogenetic stimulation of the cell bodies of the baroreceptor expressing afferents in the NDG produced robust depressor responses. Together, these results establish a novel approach for selectively targeting sensory neurons innervating the aortic arch. This approach may be used to investigate arterial baroreceptors structurally and functionally, and to assess their role in the etiology or reversal of cardiovascular disease.

10.
Australas J Dermatol ; 62(4): e524-e531, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34426977

RESUMO

BACKGROUND/OBJECTIVES: Increased rates of histopathological misdiagnosis of melanoma have been associated with incisional punch more so than shave biopsy when compared with complete excisional biopsy. It is unknown how the increasing utilisation of shave biopsy may impact melanoma diagnosis. The extent to which the provision of clinical information to the pathologist may improve diagnostic accuracy remains unclear. This study assessed the impact of both initial biopsy technique and provision of adequate clinical information to pathologists on the accuracy of histopathological diagnosis of melanoma and disease progression. METHODS: We conducted a retrospective cohort with nested case-control study of all histopathological false-negative and false-positive melanoma diagnoses from January 2014 to May 2019 from the Victorian Melanoma Service electronic database. Cases were assessed for the initial biopsy type, provision of clinical information on pathology request forms and disease progression associated with false-negative diagnosis. RESULTS: Partial shave biopsy had higher odds of false-negative (OR 5.19, 95% CI 2.89-9.32; P < 0.001) and false-positive diagnoses (OR 1.95, 95% CI 1.45-2.63; P < 0.001) of melanoma when compared with elliptical excisional biopsy. These odds ratios were comparable with those found with incisional punch biopsy. Providing the suspected clinical diagnosis to pathologists also reduced the odds of false-negative diagnosis with melanoma progression by 3.8-fold (P = 0.02). CONCLUSION: The choice of initial biopsy technique and providing the suspected clinical diagnosis to pathologists are important for correct histopathological diagnosis of cutaneous melanoma and prevention of further disease progression.


Assuntos
Biópsia , Melanoma/patologia , Neoplasias Cutâneas/patologia , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Masculino , Invasividade Neoplásica , Estadiamento de Neoplasias , Razão de Chances , Estudos Retrospectivos
11.
J Immunother Cancer ; 9(3)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33741729

RESUMO

BACKGROUND: Multiple myeloma (MM) remains an incurable disease and oncolytic viruses offer a well-tolerated addition to the therapeutic arsenal. Oncolytic reovirus has progressed to phase I clinical trials and its direct lytic potential has been extensively studied. However, to date, the role for reovirus-induced immunotherapy against MM, and the impact of the bone marrow (BM) niche, have not been reported. METHODS: This study used human peripheral blood mononuclear cells from healthy donors and in vitro co-culture of MM cells and BM stromal cells to recapitulate the resistant BM niche. Additionally, the 5TGM1-Kalw/RijHSD immunocompetent in vivo model was used to examine reovirus efficacy and characterize reovirus-induced immune responses in the BM and spleen following intravenous administration. Collectively, these in vitro and in vivo models were used to characterize the development of innate and adaptive antimyeloma immunity following reovirus treatment. RESULTS: Using the 5TGM1-Kalw/RijHSD immunocompetent in vivo model we have demonstrated that reovirus reduces both MM tumor burden and myeloma-induced bone disease. Furthermore, detailed immune characterization revealed that reovirus: (i) increased natural killer (NK) cell and CD8+ T cell numbers; (ii) activated NK cells and CD8+ T cells and (iii) upregulated effector-memory CD8+ T cells. Moreover, increased effector-memory CD8+ T cells correlated with decreased tumor burden. Next, we explored the potential for reovirus-induced immunotherapy using human co-culture models to mimic the myeloma-supportive BM niche. MM cells co-cultured with BM stromal cells displayed resistance to reovirus-induced oncolysis and bystander cytokine-killing but remained susceptible to killing by reovirus-activated NK cells and MM-specific cytotoxic T lymphocytes. CONCLUSION: These data highlight the importance of reovirus-induced immunotherapy for targeting MM cells within the BM niche and suggest that combination with agents which boost antitumor immune responses should be a priority.


Assuntos
Medula Óssea/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Matadoras Naturais/imunologia , Mieloma Múltiplo/terapia , Terapia Viral Oncolítica , Vírus Oncolíticos/imunologia , Reoviridae/imunologia , Baço/imunologia , Microambiente Tumoral/imunologia , Animais , Medula Óssea/virologia , Linfócitos T CD8-Positivos/virologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Citocinas/imunologia , Citotoxicidade Imunológica , Feminino , Humanos , Células Matadoras Naturais/virologia , Masculino , Camundongos Endogâmicos C57BL , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/virologia , Vírus Oncolíticos/patogenicidade , Reoviridae/patogenicidade , Baço/virologia , Evasão Tumoral
12.
Nat Metab ; 3(2): 258-273, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33589843

RESUMO

The anorexigenic peptide glucagon-like peptide-1 (GLP-1) is secreted from gut enteroendocrine cells and brain preproglucagon (PPG) neurons, which, respectively, define the peripheral and central GLP-1 systems. PPG neurons in the nucleus tractus solitarii (NTS) are widely assumed to link the peripheral and central GLP-1 systems in a unified gut-brain satiation circuit. However, direct evidence for this hypothesis is lacking, and the necessary circuitry remains to be demonstrated. Here we show that PPGNTS neurons encode satiation in mice, consistent with vagal signalling of gastrointestinal distension. However, PPGNTS neurons predominantly receive vagal input from oxytocin-receptor-expressing vagal neurons, rather than those expressing GLP-1 receptors. PPGNTS neurons are not necessary for eating suppression by GLP-1 receptor agonists, and concurrent PPGNTS neuron activation suppresses eating more potently than semaglutide alone. We conclude that central and peripheral GLP-1 systems suppress eating via independent gut-brain circuits, providing a rationale for pharmacological activation of PPGNTS neurons in combination with GLP-1 receptor agonists as an obesity treatment strategy.


Assuntos
Sistema Nervoso Central/fisiologia , Peptídeo 1 Semelhante ao Glucagon/fisiologia , Sistema Nervoso Periférico/fisiologia , Resposta de Saciedade/fisiologia , Animais , Ingestão de Alimentos , Feminino , Trato Gastrointestinal/inervação , Trato Gastrointestinal/fisiologia , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Peptídeos Semelhantes ao Glucagon/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Proglucagon/metabolismo , Receptores de Ocitocina/metabolismo , Nervo Vago/fisiologia
13.
J Neurosci ; 41(7): 1429-1442, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33328294

RESUMO

Blood pressure is controlled by endocrine, autonomic, and behavioral responses that maintain blood volume and perfusion pressure at levels optimal for survival. Although it is clear that central angiotensin type 1a receptors (AT1aR; encoded by the Agtr1a gene) influence these processes, the neuronal circuits mediating these effects are incompletely understood. The present studies characterize the structure and function of AT1aR neurons in the lamina terminalis (containing the median preoptic nucleus and organum vasculosum of the lamina terminalis), thereby evaluating their roles in blood pressure control. Using male Agtr1a-Cre mice, neuroanatomical studies reveal that AT1aR neurons in the area are largely glutamatergic and send projections to the paraventricular nucleus of the hypothalamus (PVN) that appear to synapse onto vasopressin-synthesizing neurons. To evaluate the functionality of these lamina terminalis AT1aR neurons, we virally delivered light-sensitive opsins and then optogenetically excited or inhibited the neurons while evaluating cardiovascular parameters or fluid intake. Optogenetic excitation robustly elevated blood pressure, water intake, and sodium intake, while optogenetic inhibition produced the opposite effects. Intriguingly, optogenetic excitation of these AT1aR neurons of the lamina terminalis also resulted in Fos induction in vasopressin neurons within the PVN and supraoptic nucleus. Further, within the PVN, selective optogenetic stimulation of afferents that arise from these lamina terminalis AT1aR neurons induced glutamate release onto magnocellular neurons and was sufficient to increase blood pressure. These cardiovascular effects were attenuated by systemic pretreatment with a vasopressin-1a-receptor antagonist. Collectively, these data indicate that excitation of lamina terminalis AT1aR neurons induces neuroendocrine and behavioral responses that increase blood pressure.SIGNIFICANCE STATEMENT Hypertension is a widespread health problem and risk factor for cardiovascular disease. Although treatments exist, a substantial percentage of patients suffer from "drug-resistant" hypertension, a condition associated with increased activation of brain angiotensin receptors, enhanced sympathetic nervous system activity, and elevated vasopressin levels. The present study highlights a role for angiotensin Type 1a receptor expressing neurons located within the lamina terminalis in regulating endocrine and behavioral responses that are involved in maintaining cardiovascular homeostasis. More specifically, data presented here reveal functional excitatory connections between angiotensin-sensitive neurons in the lamina terminals and vasopressin neurons in the paraventricular nucleus of the hypothalamus, and further indicate that activation of this circuit raises blood pressure. These neurons may be a promising target for antihypertensive therapeutics.


Assuntos
Angiotensinas/farmacologia , Arginina Vasopressina/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Vias Neurais/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Vasoconstritores/farmacologia , Animais , Núcleo Basal de Meynert/efeitos dos fármacos , Núcleo Basal de Meynert/metabolismo , Ingestão de Líquidos/efeitos dos fármacos , Genes fos/efeitos dos fármacos , Ácido Glutâmico/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Optogenética , Receptor Tipo 1 de Angiotensina/efeitos dos fármacos , Receptores de Vasopressinas/efeitos dos fármacos , Sódio na Dieta
14.
J Exp Med ; 216(11): 2479-2491, 2019 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-31467037

RESUMO

Hypothalamic-pituitary-adrenal (HPA) axis dysfunction contributes to numerous human diseases and disorders. We developed a high-affinity monoclonal antibody, CTRND05, targeting corticotropin-releasing factor (CRF). In mice, CTRND05 blocks stress-induced corticosterone increases, counteracts effects of chronic variable stress, and induces other phenotypes consistent with suppression of the HPA axis. CTRND05 induces skeletal muscle hypertrophy and increases lean body mass, effects not previously reported with small-molecule HPA-targeting pharmacologic agents. Multiorgan transcriptomics demonstrates broad HPA axis target engagement through altering levels of known HPA-responsive transcripts such as Fkbp5 and Myostatin and reveals novel HPA-responsive pathways such as the Apelin-Apelin receptor system. These studies demonstrate the therapeutic potential of CTRND05 as a suppressor of the HPA axis and serve as an exemplar of a potentially broader approach to target neuropeptides with immunotherapies, as both pharmacologic tools and novel therapeutics.


Assuntos
Anticorpos Monoclonais/farmacologia , Hormônio Liberador da Corticotropina/antagonistas & inibidores , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular Tumoral , Corticosterona/imunologia , Corticosterona/metabolismo , Hormônio Liberador da Corticotropina/imunologia , Perfilação da Expressão Gênica/métodos , Humanos , Sistema Hipotálamo-Hipofisário/imunologia , Sistema Hipotálamo-Hipofisário/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fenótipo , Sistema Hipófise-Suprarrenal/imunologia , Sistema Hipófise-Suprarrenal/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Estresse Fisiológico/imunologia
15.
J Immunother Cancer ; 7(1): 164, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262361

RESUMO

BACKGROUND: The oncolytic virus, coxsackievirus A21 (CVA21), has shown promise as a single agent in several clinical trials and is now being tested in combination with immune checkpoint blockade. Combination therapies offer the best chance of disease control; however, the design of successful combination strategies requires a deeper understanding of the mechanisms underpinning CVA21 efficacy, in particular, the role of CVA21 anti-tumor immunity. Therefore, this study aimed to examine the ability of CVA21 to induce human anti-tumor immunity, and identify the cellular mechanism responsible. METHODS: This study utilized peripheral blood mononuclear cells from i) healthy donors, ii) Acute Myeloid Leukemia (AML) patients, and iii) patients taking part in the STORM clinical trial, who received intravenous CVA21; patients receiving intravenous CVA21 were consented separately in accordance with local institutional ethics review and approval. Collectively, these blood samples were used to characterize the development of innate and adaptive anti-tumor immune responses following CVA21 treatment. RESULTS: An Initial characterization of peripheral blood mononuclear cells, collected from cancer patients following intravenous infusion of CVA21, confirmed that CVA21 activated immune effector cells in patients. Next, using hematological disease models which were sensitive (Multiple Myeloma; MM) or resistant (AML) to CVA21-direct oncolysis, we demonstrated that CVA21 stimulated potent anti-tumor immune responses, including: 1) cytokine-mediated bystander killing; 2) enhanced natural killer cell-mediated cellular cytotoxicity; and 3) priming of tumor-specific cytotoxic T lymphocytes, with specificity towards known tumor-associated antigens. Importantly, immune-mediated killing of both MM and AML, despite AML cells being resistant to CVA21-direct oncolysis, was observed. Upon further examination of the cellular mechanisms responsible for CVA21-induced anti-tumor immunity we have identified the importance of type I IFN for NK cell activation, and demonstrated that both ICAM-1 and plasmacytoid dendritic cells were key mediators of this response. CONCLUSION: This work supports the development of CVA21 as an immunotherapeutic agent for the treatment of both AML and MM. Additionally, the data presented provides an important insight into the mechanisms of CVA21-mediated immunotherapy to aid the development of clinical biomarkers to predict response and rationalize future drug combinations.


Assuntos
Enterovirus , Leucemia Mieloide Aguda/terapia , Terapia Viral Oncolítica , Vírus Oncolíticos , Imunidade Adaptativa , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Feminino , Humanos , Imunidade Inata , Molécula 1 de Adesão Intercelular/imunologia , Leucemia Mieloide Aguda/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T Citotóxicos/imunologia
16.
Mol Ther ; 27(6): 1139-1152, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31053413

RESUMO

A clinical oncolytic herpes simplex virus (HSV) encoding granulocyte-macrophage colony-stimulating factor (GM-CSF), talimogene laherparepvec, causes regression of injected and non-injected melanoma lesions in patients and is now licensed for clinical use in advanced melanoma. To date, limited data are available regarding the mechanisms of human anti-tumor immune priming, an improved understanding of which could inform the development of future combination strategies with improved efficacy. This study addressed direct oncolysis and innate and adaptive human immune-mediated effects of a closely related HSV encoding GM-CSF (HSVGM-CSF) alone and in combination with histone deacetylase inhibition. We found that HSVGM-CSF supported activation of anti-melanoma immunity via monocyte-mediated type I interferon production, which activates NK cells, and viral maturation of immature dendritic cells (iDCs) into potent antigen-presenting cells for cytotoxic T lymphocyte (CTL) priming. Addition of the histone deacetylase inhibitor valproic acid (VPA) to HSVGM-CSF treatment of tumor cells increased viral replication, viral GM-CSF production, and oncolysis and augmented the development of anti-tumor immunity. Mechanistically, VPA increased expression of activating ligands for NK cell recognition and induced expression of tumor-associated antigens, supporting innate NK cell killing and CTL priming. These data support the clinical combination of talimogene laherparepvec with histone deacetylase inhibition to enhance oncolysis and anti-tumor immunity.


Assuntos
Inibidores de Histona Desacetilases/uso terapêutico , Melanoma/terapia , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/metabolismo , Simplexvirus/imunologia , Neoplasias Cutâneas/terapia , Ácido Valproico/uso terapêutico , Antígenos de Neoplasias/efeitos dos fármacos , Antígenos de Neoplasias/metabolismo , Antineoplásicos Imunológicos/uso terapêutico , Produtos Biológicos/uso terapêutico , Sobrevivência Celular/genética , Células Dendríticas/imunologia , Quimioterapia Combinada , Vetores Genéticos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Herpesvirus Humano 1 , Humanos , Interferon Tipo I/metabolismo , Células Matadoras Naturais/imunologia , Células MCF-7 , Melanoma/patologia , Vírus Oncolíticos/genética , Simplexvirus/genética , Neoplasias Cutâneas/patologia , Linfócitos T Citotóxicos/imunologia
17.
J Anal Toxicol ; 43(5): 346-352, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30698723

RESUMO

New psychoactive substances (NPSs) have become an integral part of the recreational drug market with "new" compounds being reported by the European Monitoring Centre for Drugs and Drug Addiction weekly. Due to the changing nature of NPSs, it is impractical to carry out single analyte or even simple class quantitation. Although several gas chromatography-mass spectrometry (GC-MS) methods have been developed these are typically class specific. We present a validated GC-MS method for the quantitation of 2-DPMP, 3-MeO-PCE, 3-MeO-PCP, 5-APB, 6-APB, benzedrone, butylone, ethylone, flephedrone, methiopropamine, MDPV, mephedrone, methoxetamine, methylone, naphyrone, 25B-NBOME, 25C-NBOME, 25D-NBOMe, 25E-NBOME, 25H-NBOME, 25I-NBOME, Mescaline-NBOME and 25P-NBOME in blood and urine samples. Sample preparation was carried out using solid-phase extraction followed by derivatisation and analysis by GC-MS. Parameters investigated for validation included bias, precision, linear calibration model, carryover, interferences, limit of detection, limit of quantification, and autosampler and freeze/thaw stability. All drugs yielded successful results for each of these parameters as per SWGTOX guidelines. The GC-MS method was used for the reanalysis of 12 blood samples (eight cases) where 25I-NBOMe, 25C-NBOMe, methoxetamine and methylone had previously been detected by NMS laboratories. This GC-MS method was able to quantitatively detect these drugs in 75% of the blood samples, 42% of which contained either 25C-NBOMe or 25I-NBOMe. This method accurately allows for the simultaneous quantification of a wide variety of compounds via GC-MS, in particular NBOMe compounds which are typically analysed by liquid chromatography-tandem mass spectrometry which is not available in all laboratories.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Drogas Ilícitas , Psicotrópicos , Detecção do Abuso de Substâncias/métodos , Calibragem , Humanos , Drogas Ilícitas/sangue , Drogas Ilícitas/urina , Limite de Detecção , Psicotrópicos/sangue , Psicotrópicos/urina , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/instrumentação , Detecção do Abuso de Substâncias/normas
18.
Intern Med J ; 48(9): 1035-1040, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30182394

RESUMO

BACKGROUND: Oral health is an important predictor for general health, and poor oral health is interrelated with the manifestations of systemic disease. AIM: To determine the extent of oral health education in medical schools across Australia. METHODS: A survey of Australian medical schools was conducted (September 2013 to June 2014). Participants were administrators and curricula coordinators of medical programmes. The main outcome measures were teaching hours of specific areas of oral health education. Data were descriptively analysed. RESULTS: Participants from 8 of 18 universities responded to the questionnaire. The total hours dedicated to oral health in the medical programmes were: zero in one school; less than 2 h in three schools, 6-10 h in three schools and 30 h in one school. Only four schools taught the correlation between oral health and overall health, two schools taught about dental diseases (caries and periodontal disease), three schools taught dental trauma management and six schools taught oral anatomy. Only five schools taught about oral cancer: two of these taught about cancer for 10-15 min. No school reported hands-on training in an oral health setting. CONCLUSIONS: The results indicate that Australian medical school graduates have little, if any, foundational knowledge of oral health (dental caries, bidirectional relationship between diabetes and periodontal disease, oral cancer and dental emergencies). The recognition of poor oral health plays a significant part in the early detection and care of chronic diseases. The teaching of fundamental oral health to medical students is crucial and should be integrated into medical school curricula.


Assuntos
Currículo/estatística & dados numéricos , Saúde Bucal/educação , Faculdades de Medicina/estatística & dados numéricos , Ensino/estatística & dados numéricos , Austrália , Humanos , Avaliação de Programas e Projetos de Saúde , Inquéritos e Questionários , Fatores de Tempo
19.
Proc Natl Acad Sci U S A ; 115(7): E1540-E1549, 2018 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-29386395

RESUMO

Inhibition of immune checkpoints programmed death 1 (PD-1) and cytotoxic T lymphocyte-associated protein 4 (CTLA-4) on T cells results in durable antitumor activity in melanoma patients. Despite high frequency of melanoma brain metastases (BrM) and associated poor prognosis, the activity and mechanisms of immune checkpoint inhibitors (ICI) in metastatic tumors that develop within the "immune specialized" brain microenvironment, remain elusive. We established a melanoma tumor transplantation model with intracranial plus extracranial (subcutaneous) tumor, mimicking the clinically observed coexistence of metastases inside and outside the brain. Strikingly, intracranial ICI efficacy was observed only when extracranial tumor was present. Extracranial tumor was also required for ICI-induced increase in CD8+ T cells, macrophages, and microglia in brain tumors, and for up-regulation of immune-regulatory genes. Combined PD-1/CTLA-4 blockade had a superior intracranial efficacy over the two monotherapies. Cell depletion studies revealed that NK cells and CD8+ T cells were required for intracranial anti-PD-1/anti-CTLA-4 efficacy. Rather than enhancing CD8+ T cell activation and expansion within intracranial tumors, PD-1/CTLA-4 blockade dramatically (∼14-fold) increased the trafficking of CD8+ T cells to the brain. This was mainly through the peripheral expansion of homing-competent effector CD8+ T cells and potentially further enhanced through up-regulation of T cell entry receptors intercellular adhesion molecule 1 and vascular adhesion molecule 1 on tumor vasculature. Our study indicates that extracranial activation/release of CD8+ T cells from PD-1/CTLA-4 inhibition and potentiation of their recruitment to the brain are paramount to the intracranial anti-PD-1/anti-CTLA-4 activity, suggesting augmentation of these processes as an immune therapy-enhancing strategy in metastatic brain cancer.


Assuntos
Anticorpos Monoclonais/farmacologia , Neoplasias Encefálicas/terapia , Linfócitos T CD8-Positivos/imunologia , Linfócitos do Interstício Tumoral/imunologia , Melanoma Experimental/terapia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Reguladores/imunologia , Animais , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/secundário , Feminino , Granzimas/imunologia , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/imunologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/secundário , Neoplasias Cutâneas/terapia , Carga Tumoral , Células Tumorais Cultivadas
20.
Sci Transl Med ; 10(422)2018 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-29298869

RESUMO

Immune checkpoint inhibitors, including those targeting programmed cell death protein 1 (PD-1), are reshaping cancer therapeutic strategies. Evidence suggests, however, that tumor response and patient survival are determined by tumor programmed death ligand 1 (PD-L1) expression. We hypothesized that preconditioning of the tumor immune microenvironment using targeted, virus-mediated interferon (IFN) stimulation would up-regulate tumor PD-L1 protein expression and increase cytotoxic T cell infiltration, improving the efficacy of subsequent checkpoint blockade. Oncolytic viruses (OVs) represent a promising form of cancer immunotherapy. For brain tumors, almost all studies to date have used direct intralesional injection of OV, because of the largely untested belief that intravenous administration will not deliver virus to this site. We show, in a window-of-opportunity clinical study, that intravenous infusion of oncolytic human Orthoreovirus (referred to herein as reovirus) leads to infection of tumor cells subsequently resected as part of standard clinical care, both in high-grade glioma and in brain metastases, and increases cytotoxic T cell tumor infiltration relative to patients not treated with virus. We further show that reovirus up-regulates IFN-regulated gene expression, as well as the PD-1/PD-L1 axis in tumors, via an IFN-mediated mechanism. Finally, we show that addition of PD-1 blockade to reovirus enhances systemic therapy in a preclinical glioma model. These results support the development of combined systemic immunovirotherapy strategies for the treatment of both primary and secondary tumors in the brain.


Assuntos
Neoplasias Encefálicas/terapia , Vírus Oncolíticos/patogenicidade , Animais , Glioma/terapia , Humanos , Imunoterapia/métodos , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/metabolismo
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