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1.
PLoS Pathog ; 19(5): e1011044, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37216391

RESUMEN

Interactions between coinfecting pathogens have the potential to alter the course of infection and can act as a source of phenotypic variation in susceptibility between hosts. This phenotypic variation may influence the evolution of host-pathogen interactions within host species and interfere with patterns in the outcomes of infection across host species. Here, we examine experimental coinfections of two Cripaviruses-Cricket Paralysis Virus (CrPV), and Drosophila C Virus (DCV)-across a panel of 25 Drosophila melanogaster inbred lines and 47 Drosophilidae host species. We find that interactions between these viruses alter viral loads across D. melanogaster genotypes, with a ~3 fold increase in the viral load of DCV and a ~2.5 fold decrease in CrPV in coinfection compared to single infection, but we find little evidence of a host genetic basis for these effects. Across host species, we find no evidence of systematic changes in susceptibility during coinfection, with no interaction between DCV and CrPV detected in the majority of host species. These results suggest that phenotypic variation in coinfection interactions within host species can occur independently of natural host genetic variation in susceptibility, and that patterns of susceptibility across host species to single infections can be robust to the added complexity of coinfection.


Asunto(s)
Coinfección , Dicistroviridae , Animales , Drosophila melanogaster/genética , Especificidad del Huésped , Interacciones Huésped-Patógeno/genética
2.
PLoS Pathog ; 19(6): e1011433, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37289828

RESUMEN

Virus host shifts, where a virus transmits to and infects a novel host species, are a major source of emerging infectious disease. Genetic similarity between eukaryotic host species has been shown to be an important determinant of the outcome of virus host shifts, but it is unclear if this is the case for prokaryotes where anti-virus defences can be transmitted by horizontal gene transfer and evolve rapidly. Here, we measure the susceptibility of 64 strains of Staphylococcaceae bacteria (48 strains of Staphylococcus aureus and 16 non-S. aureus species spanning 2 genera) to the bacteriophage ISP, which is currently under investigation for use in phage therapy. Using three methods-plaque assays, optical density (OD) assays, and quantitative (q)PCR-we find that the host phylogeny explains a large proportion of the variation in susceptibility to ISP across the host panel. These patterns were consistent in models of only S. aureus strains and models with a single representative from each Staphylococcaceae species, suggesting that these phylogenetic effects are conserved both within and among host species. We find positive correlations between susceptibility assessed using OD and qPCR and variable correlations between plaque assays and either OD or qPCR, suggesting that plaque assays alone may be inadequate to assess host range. Furthermore, we demonstrate that the phylogenetic relationships between bacterial hosts can generally be used to predict the susceptibility of bacterial strains to phage infection when the susceptibility of closely related hosts is known, although this approach produced large prediction errors in multiple strains where phylogeny was uninformative. Together, our results demonstrate the ability of bacterial host evolutionary relatedness to explain differences in susceptibility to phage infection, with implications for the development of ISP both as a phage therapy treatment and as an experimental system for the study of virus host shifts.


Asunto(s)
Bacteriófagos , Staphylococcaceae , Fagos de Staphylococcus , Bacteriófagos/fisiología , Especificidad del Huésped , Filogenia , Reacción en Cadena de la Polimerasa , Staphylococcaceae/clasificación , Staphylococcaceae/virología , Staphylococcus aureus/virología , Fagos de Staphylococcus/fisiología , Ensayo de Placa Viral , Replicación Viral
3.
J Virol ; 96(22): e0129022, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36342296

RESUMEN

H9N2 avian influenza viruses (AIVs) have donated internal gene segments during the emergence of zoonotic AIVs, including H7N9. We used reverse genetics to generate A/Anhui/1/13 (H7N9) and three reassortant viruses (2:6 H7N9) which contained the hemagglutinin and neuraminidase from Anhui/13 (H7N9) and the six internal gene segments from H9N2 AIVs belonging to (i) G1 subgroup 2, (ii) G1 subgroup 3, or (iii) BJ94 lineages, enzootic in different regions throughout Asia. Infection of chickens with the 2:6 H7N9 containing G1-like H9N2 internal genes conferred attenuation in vivo, with reduced shedding and transmission to contact chickens. However, possession of BJ94-like H9N2 internal genes resulted in more rapid transmission and significantly elevated cloacal shedding compared to the parental Anhui/13 H7N9. In vitro analysis showed that the 2:6 H7N9 with BJ94-like internal genes had significantly increased replication compared to the Anhui/13 H7N9 in chicken cells. In vivo coinfection experiments followed, where chickens were coinfected with pairs of Anhui/13 H7N9 and a 2:6 H7N9 reassortant. During ensuing transmission events, the Anhui/13 H7N9 virus outcompeted 2:6 H7N9 AIVs with internal gene segments of BJ94-like or G1-like H9N2 viruses. Coinfection did lead to the emergence of novel reassortant genotypes that were transmitted to contact chickens. Some of the reassortant viruses had a greater replication in chicken and human cells compared to the progenitors. We demonstrated that the internal gene cassette determines the transmission fitness of H7N9 viruses in chickens, and the reassortment events can generate novel H7N9 genotypes with increased virulence in chickens and enhanced zoonotic potential. IMPORTANCE H9N2 avian influenza viruses (AIVs) are enzootic in poultry in different geographical regions. The internal genes of these viruses can be exchanged with other zoonotic AIVs, most notably the A/Anhui/1/2013-lineage H7N9, which can give rise to new virus genotypes with increased veterinary, economic and public health threats to both poultry and humans. We investigated the propensity of the internal genes of H9N2 viruses (G1 or BJ94) in the generation of novel reassortant H7N9 AIVs. We observed that the internal genes of H7N9 which were derivative of BJ94-like H9N2 virus have a fitness advantage compared to those from the G1-like H9N2 viruses for efficient transmission among chickens. We also observed the generation of novel reassortant viruses during chicken transmission which infected and replicated efficiently in human cells. Therefore, such emergent reassortant genotypes may pose an elevated zoonotic threat.


Asunto(s)
Coinfección , Subtipo H7N9 del Virus de la Influenza A , Subtipo H9N2 del Virus de la Influenza A , Gripe Aviar , Gripe Humana , Animales , Humanos , Subtipo H7N9 del Virus de la Influenza A/genética , Subtipo H9N2 del Virus de la Influenza A/genética , Pollos , Virus Reordenados/genética , Aves de Corral , Filogenia
4.
J Virol ; 96(5): e0185621, 2022 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-35019727

RESUMEN

An H7N9 low-pathogenicity avian influenza virus (LPAIV) emerged in 2013 through genetic reassortment between H9N2 and other LPAIVs circulating in birds in China. This virus causes inapparent clinical disease in chickens, but zoonotic transmission results in severe and fatal disease in humans. To examine a natural reassortment scenario between H7N9 and G1 lineage H9N2 viruses predominant in the Indian subcontinent, we performed an experimental coinfection of chickens with A/Anhui/1/2013/H7N9 (Anhui/13) virus and A/Chicken/Pakistan/UDL-01/2008/H9N2 (UDL/08) virus. Plaque purification and genotyping of the reassortant viruses shed via the oropharynx of contact chickens showed H9N2 and H9N9 as predominant subtypes. The reassortant viruses shed by contact chickens also showed selective enrichment of polymerase genes from H9N2 virus. The viable "6+2" reassortant H9N9 (having nucleoprotein [NP] and neuraminidase [NA] from H7N9 and the remaining genes from H9N2) was successfully shed from the oropharynx of contact chickens, plus it showed an increased replication rate in human A549 cells and a significantly higher receptor binding to α2,6 and α2,3 sialoglycans compared to H9N2. The reassortant H9N9 virus also had a lower fusion pH, replicated in directly infected ferrets at similar levels compared to H7N9 and transmitted via direct contact. Ferrets exposed to H9N9 via aerosol contact were also found to be seropositive, compared to H7N9 aerosol contact ferrets. To the best of our knowledge, this is the first study demonstrating that cocirculation of H7N9 and G1 lineage H9N2 viruses could represent a threat for the generation of novel reassortant H9N9 viruses with greater virulence in poultry and a zoonotic potential. IMPORTANCE We evaluated the consequences of reassortment between the H7N9 and the contemporary H9N2 viruses of the G1 lineage that are enzootic in poultry across the Indian subcontinent and the Middle East. Coinfection of chickens with these viruses resulted in the emergence of novel reassortant H9N9 viruses with genes derived from both H9N2 and H7N9 viruses. The "6+2" reassortant H9N9 (having NP and NA from H7N9) virus was shed from contact chickens in a significantly higher proportion compared to most of the reassortant viruses, showed significantly increased replication fitness in human A549 cells, receptor binding toward human (α2,6) and avian (α2,3) sialic acid receptor analogues, and the potential to transmit via contact among ferrets. This study demonstrated the ability of viruses that already exist in nature to exchange genetic material, highlighting the potential emergence of viruses from these subtypes with zoonotic potential.


Asunto(s)
Coinfección , Subtipo H7N9 del Virus de la Influenza A , Subtipo H9N2 del Virus de la Influenza A , Gripe Aviar , Virus Reordenados , Animales , Pollos , Coinfección/veterinaria , Hurones , Humanos , Subtipo H7N9 del Virus de la Influenza A/genética , Subtipo H9N2 del Virus de la Influenza A/genética , Gripe Aviar/virología , Gripe Humana , Filogenia , Aves de Corral , Virus Reordenados/genética , Virus Reordenados/patogenicidad
5.
FASEB J ; 33(1): 1299-1312, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30148676

RESUMEN

Emerging evidence indicates that G-protein coupled receptor 55 (GPR55), a nonclassic receptor of the endocannabinoid system that is activated by L-α-lysophosphatidylinositol and various cannabinoid ligands, may regulate endocrine function and energy metabolism. We examined how GPR55 deficiency and modulation affects insulin signaling in skeletal muscle, adipose tissue, and liver alongside expression analysis of proteins implicated in insulin action and energy metabolism. We show that GPR55-null mice display decreased insulin sensitivity in these tissues, as evidenced by reduced phosphorylation of PKB/Akt and its downstream targets, concomitant with increased adiposity and reduced physical activity relative to wild-type counterparts. Impaired tissue insulin sensitivity coincided with reduced insulin receptor substrate-1 abundance in skeletal muscle, whereas in liver and epididymal fat it was associated with increased expression of the 3-phosphoinoistide lipid phosphatase, phosphatase and tensin homolog. In contrast, GPR55 activation enhanced insulin signaling in cultured skeletal muscle cells, adipocytes, and hepatocytes; this response was negated by receptor antagonists and GPR55 gene silencing in L6 myotubes. Sustained GPR55 antagonism in 3T3-L1 adipocytes enhanced expression of proteins implicated in lipogenesis and promoted triglyceride accumulation. Our findings identify GPR55 as a positive regulator of insulin action and adipogenesis and as a potential therapeutic target for countering obesity-induced metabolic dysfunction and insulin resistance.-Lipina, C., Walsh, S. K., Mitchell, S. E., Speakman, J. R., Wainwright, C. L., Hundal, H. S. GPR55 deficiency is associated with increased adiposity and impaired insulin signaling in peripheral metabolic tissues.


Asunto(s)
Tejido Adiposo/metabolismo , Adiposidad/genética , Insulina/metabolismo , Hígado/metabolismo , Músculo Esquelético/metabolismo , Receptores de Cannabinoides/fisiología , Transducción de Señal , Células 3T3-L1 , Tejido Adiposo/citología , Animales , Línea Celular Tumoral , Metabolismo Energético , Humanos , Hígado/citología , Ratones , Ratones Noqueados , Músculo Esquelético/citología , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Receptores de Cannabinoides/genética
6.
Br J Nutr ; 121(9): 961-973, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30791962

RESUMEN

Zn plays an important role in maintaining the anti-oxidant status within the heart and helps to counter the acute redox stress that occurs during myocardial ischaemia and reperfusion. Individuals with low Zn levels are at greater risk of developing an acute myocardial infarction; however, the impact of this on the extent of myocardial injury is unknown. The present study aimed to compare the effects of dietary Zn depletion with in vitro removal of Zn (N,N,N',N'-tetrakis(2-pyridinylmethyl)-1,2-ethanediamine (TPEN)) on the outcome of acute myocardial infarction and vascular function. Male Sprague-Dawley rats were fed either a Zn-adequate (35 mg Zn/kg diet) or Zn-deficient (<1 mg Zn/kg diet) diet for 2 weeks before heart isolation. Perfused hearts were subjected to a 30 min ischaemia/2 h reperfusion (I/R) protocol, during which time ventricular arrhythmias were recorded and after which infarct size was measured, along with markers of anti-oxidant status. In separate experiments, hearts were challenged with the Zn chelator TPEN (10 µm) before ischaemia onset. Both dietary and TPEN-induced Zn depletion significantly extended infarct size; dietary Zn depletion was associated with reduced total cardiac glutathione (GSH) levels, while TPEN decreased cardiac superoxide dismutase 1 levels. TPEN, but not dietary Zn depletion, also suppressed ventricular arrhythmias and depressed vascular responses to nitric oxide. These findings demonstrate that both modes of Zn depletion worsen the outcome from I/R but through different mechanisms. Dietary Zn deficiency, resulting in reduced cardiac GSH, is the most appropriate model for determining the role of endogenous Zn in I/R injury.


Asunto(s)
Dieta/efectos adversos , Glutatión/metabolismo , Isquemia Miocárdica/etiología , Daño por Reperfusión Miocárdica/etiología , Zinc/deficiencia , Animales , Corazón/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-Dawley
7.
J Cancer Educ ; 34(2): 229-233, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-29052110

RESUMEN

Despite a growing number of clinical trials and supportive care programs for cancer survivors, recruitment of patients for these opportunities during the survivorship phase of care is challenging. We piloted a novel process to systematically educate patients about available research studies and supportive care programs as part of a survivorship care visit. Between 3/2015 and 8/2015, patients seen in the Adult Survivorship Program who had not previously received a treatment summary and survivorship care plan (TS/SCP) were provided with one accompanied by a list of survivorship research studies and care programs tailored to their diagnosis. Survivorship providers discussed the opportunities and recorded whether the patient was interested in relevant studies and placed referrals to study staff. Following the visit, we tracked study enrollment and surveyed patients about their experience. Fifty of 56 (89%) pilot participants completed the survey. Almost all (98%) reported that the TS/SCP visit and document helped with knowledge of research opportunities and supportive care interventions. Following receipt of the TS/SCP, 44% were interested in at least one study and in further follow-up with research staff. Of the 30 survivors eligible for at least one study, 6 (20%) have enrolled in at least one study to date. This pilot program demonstrates that the systematic sharing of available clinical studies and supportive care programming as part of a survivorship care plan visit is feasible and well received by cancer survivors and may facilitate and enhance accrual to clinical trials in the survivorship phase of care.


Asunto(s)
Actitud Frente a la Salud , Investigación Biomédica , Supervivientes de Cáncer , Adulto , Anciano , Ensayos Clínicos como Asunto , Estudios de Factibilidad , Femenino , Humanos , Persona de Mediana Edad , Neoplasias/terapia , Planificación de Atención al Paciente , Proyectos Piloto , Encuestas y Cuestionarios , Supervivencia
8.
Oncologist ; 22(7): 860-863, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28408620

RESUMEN

Oncofertility is a unique, multidisciplinary field that serves to bridge the gap between available fertility resources and the special reproductive needs of cancer patients. Oncofertility is a growing field due to the increasing number of survivors, development of new oncologic therapies, extension of duration of therapies, and development and refinement of reproductive therapies. While the technologies and demand for services expand, clinicians need to be appropriately prepared for dealing with various clinical scenarios that may require ethical deliberation. Three real cases are presented in which the patient wishes to pursue reproductive assistance, but her decision is met with hesitance or uncertainty by her care team. Discussion of these clinical scenarios highlights ethical implications of oncofertility practice and serves to highlight the need for the establishment of multidisciplinary care teams and guidelines to support both clinicians and patients. IMPLICATIONS FOR PRACTICE: The growing field of oncofertility is ripe for conflict between patient autonomy and medical values due to the nature of cancer and associated threat on an individual's health and survival, as well as the personal significance of childbearing. Cases are presented and ethical implications are discussed to further explore the inherent difficulties in oncofertility practice and guide clinicians in similar situations. Developing guidelines and establishing multidisciplinary teams to facilitate oncofertility discussions and care, as well as training of clinical team members, may improve patient safety, well-being, and satisfaction within the context of fertility decision making, care, and outcomes.


Asunto(s)
Preservación de la Fertilidad/ética , Recuperación del Oocito/efectos adversos , Autonomía Personal , Complicaciones Neoplásicas del Embarazo , Adulto , Neoplasias de la Mama , Criopreservación/métodos , Transferencia de Embrión/ética , Femenino , Preservación de la Fertilidad/métodos , Humanos , Recuperación del Oocito/ética , Recuperación del Oocito/métodos , Oocitos/fisiología , Embarazo , Adulto Joven
9.
Glia ; 61(12): 1990-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24123456

RESUMEN

Schwann cells (SCs) are integral to peripheral nerve biology, contributing to saltatory conduction along axons, nerve and axon development, and axonal regeneration. SCs also provide a microenvironment favoring neural regeneration partially due to production of several neurotrophic factors. Dysfunction of SCs may also play an important role in the pathogenesis of peripheral nerve diseases such as diabetic peripheral neuropathy where hyperglycemia is often considered pathogenic. In order to study the impact of diabetes mellitus (DM) upon the regenerative capacity of adult SCs, we investigated the differential production of the neurotrophic factors nerve growth factor (NGF) and neurotrophin-3 (NT3) by SCs harvested from the sciatic nerves of murine models of type 1 DM (streptozotocin treated C57BL/6J mice) and type 2 DM (LepR(-/-) or db/db mice) or non-diabetic cohorts. In vitro, SCs from diabetic and control mice were maintained under similar hyperglycemic and euglycemic conditions respectively. Mature SCs from diabetic mice produced lower levels of NGF and NT3 under hyperglycemic conditions when compared to SCs in euglycemia. In addition, SCs from both DM and non-DM mice appear to be incapable of insulin production, but responded to exogenous insulin with greater proliferation and heightened myelination potentiation. Moreover, SCs from diabetic animals showed poorer association with co-cultured axons. Hyperglycemia had significant impact upon SCs, potentially contributing to the pathogenesis of diabetic peripheral neuropathy.


Asunto(s)
Axones/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Factor de Crecimiento Nervioso/metabolismo , Neurotrofina 3/metabolismo , Células de Schwann/metabolismo , Animales , Axones/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Hiperglucemia/metabolismo , Insulina/metabolismo , Insulina/farmacología , Ratones , Regeneración Nerviosa/efectos de los fármacos , Regeneración Nerviosa/fisiología , Células de Schwann/efectos de los fármacos , Nervio Ciático/efectos de los fármacos , Nervio Ciático/metabolismo
10.
J Proteome Res ; 10(8): 3660-73, 2011 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-21671558

RESUMEN

Being born small for gestational age (SGA) confers increased risks of perinatal morbidity and mortality and increases the risk of cardiovascular complications and diabetes in later life. Accumulating evidence suggests that the etiology of SGA is usually associated with poor placental vascular development in early pregnancy. We examined metabolomic profiles using ultra performance liquid chromatography-mass spectrometry (UPLC-MS) in three independent studies: (a) venous cord plasma from normal and SGA babies, (b) plasma from a rat model of placental insufficiency and controls, and (c) early pregnancy peripheral plasma samples from women who subsequently delivered a SGA baby and controls. Multivariate analysis by cross-validated Partial Least Squares Discriminant Analysis (PLS-DA) of all 3 studies showed a comprehensive and similar disruption of plasma metabolism. A multivariate predictive model combining 19 metabolites produced by a Genetic Algorithm-based search program gave an Odds Ratio for developing SGA of 44, with an area under the Receiver Operator Characteristic curve of 0.9. Sphingolipids, phospholipids, carnitines, and fatty acids were among this panel of metabolites. The finding of a consistent discriminatory metabolite signature in early pregnancy plasma preceding the onset of SGA offers insight into disease pathogenesis and offers the promise of a robust presymptomatic screening test.


Asunto(s)
Recién Nacido Pequeño para la Edad Gestacional , Primer Trimestre del Embarazo/metabolismo , Animales , Cromatografía Liquida , Femenino , Retardo del Crecimiento Fetal , Humanos , Recién Nacido , Espectrometría de Masas , Modelos Animales , Análisis Multivariante , Embarazo , Curva ROC , Ratas , Ratas Sprague-Dawley
11.
Biochem Pharmacol ; 188: 114560, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33844984

RESUMEN

Emerging evidence suggests that G protein coupled receptor 55 (GPR55) may influence adrenoceptor function/activity in the cardiovascular system. Whether this reflects direct interaction (dimerization) between receptors or signalling crosstalk has not been investigated. This study explored the interaction between GPR55 and the alpha 1A-adrenoceptor (α1A-AR) in the cardiovascular system and the potential to influence function/signalling activities. GPR55 and α1A-AR mediated changes in both cardiac and vascular function was assessed in male wild-type (WT) and GPR55 homozygous knockout (GPR55-/-) mice by pressure volume loop analysis and isolated vessel myography, respectively. Dimerization of GPR55 with the α1A-AR was examined in transfected Chinese hamster ovary-K1 (CHO-K1) cells via Bioluminescence Resonance Energy Transfer (BRET). GPR55 and α1A-AR mediated signalling (extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation) was investigated in neonatal rat ventricular cardiomyocytes using AlphaScreen proximity assays. GPR55-/- mice exhibited both enhanced pressor and inotropic responses to A61603 (α1A-AR agonist), while in isolated vessels, A61603 induced vasoconstriction was attenuated by a GPR55-dependent mechanism. Conversely, GPR55-mediated vasorelaxation was not altered by pharmacological blockade of α1A-ARs with tamsulosin. While cellular studies demonstrated that GPR55 and α1A-AR failed to dimerize, pharmacological blockade of GPR55 altered α1A-AR mediated signalling and reduced ERK1/2 phosphorylation. Taken together, this study provides evidence that GPR55 and α1A-AR do not dimerize to form heteromers, but do interact at the signalling level to modulate the function of α1A-AR in the cardiovascular system.


Asunto(s)
Multimerización de Proteína/fisiología , Receptores Adrenérgicos alfa 1/genética , Receptores Adrenérgicos alfa 1/metabolismo , Receptores de Cannabinoides/deficiencia , Receptores de Cannabinoides/genética , Agonistas de Receptores Adrenérgicos alfa 1/farmacología , Animales , Animales Recién Nacidos , Células CHO , Células Cultivadas , Cricetinae , Cricetulus , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Técnicas de Cultivo de Órganos , Embarazo , Multimerización de Proteína/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
12.
Eur J Neurosci ; 31(6): 1074-90, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20377620

RESUMEN

Nerve transfer procedures involving the repair of a distal denervated nerve element with that of a foreign proximal nerve have become increasingly popular for clinical nerve repair as a surgical alternative to autologous nerve grafting. However, the functional outcomes and the central plasticity for these procedures remain poorly defined, particularly for a clinically relevant rodent model of hindlimb nerve transfer. We therefore evaluated the effect of selective tibial branch nerve transfer on behavioural recovery in animals following acute transection of the deep peroneal nerve. The results indicate that not only can hindlimb nerve transfers be successfully accomplished in a rat model but that these animals display a return of skilled locomotor function on a par with animals that underwent direct deep peroneal nerve repair (the current gold standard). At 2 months, ground reaction force analysis demonstrated that partial restoration of braking forces occurred in the nerve transfer group, whereas the direct repair group had fully restored these forces to similar to baseline levels. Ankle kinematic analysis revealed that only animals in the direct repair group significantly recovered flexion during the step cycle, indicating a recovery of surgically induced foot drop. Terminal electrophysiological and myological assessments demonstrated similar levels of reinnervation, whereas retrograde labelling studies confirmed that the peroneal nerve-innervated muscles were innervated by neurons from the tibial nerve pool in the nerve transfer group. Our results demonstrate a task-dependent recovery process, where skilled locomotor recovery is similar between nerve transfer and direct repair animals, whereas flat surface locomotion is significantly better in direct repair animals.


Asunto(s)
Conducta Animal/fisiología , Regeneración Nerviosa/fisiología , Transferencia de Nervios/métodos , Neuropatías Peroneas/cirugía , Recuperación de la Función/fisiología , Nervio Tibial/trasplante , Potenciales de Acción/fisiología , Animales , Fenómenos Biomecánicos , Dextranos , Modelos Animales de Enfermedad , Electromiografía/métodos , Miembro Posterior/fisiopatología , Masculino , Actividad Motora/fisiología , Destreza Motora/fisiología , Fuerza Muscular/fisiología , Músculo Esquelético/fisiopatología , Neuropatías Peroneas/patología , Neuropatías Peroneas/fisiopatología , Ratas , Ratas Endogámicas Lew , Rodaminas , Nervio Tibial/fisiología , Factores de Tiempo
13.
Pharmacol Res Perspect ; 7(3): e00487, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31149342

RESUMEN

The phospholipid l-α-lysophosphatidylinositol (LPI), an endogenous ligand for GPR55, is elevated in patients with acute coronary syndrome, and a GPR55 antagonist cannabidiol (CBD) reduces experimental ischemia/reperfusion (I/R) injury. While LPI activates multiple signaling pathways, little is known about which ones are important in cardiomyocytes. In this study we explored whether activation of the Rho kinase/ROCK/p38 MAPK pathway is responsible for LPI-induced extension of I/R injury. Using a high-throughput screening method (dynamic mass redistribution; DMR), mouse- and human-induced pluripotent stem cell (iPSC) cardiomyocytes exposed to LPI were shown to exhibit a rapid, sustained, and concentration-dependent (1 nmol L-1-30 µmol L-1) cellular response. Y-27632 (ROCK inhibitor; 10 & 50 µmol L-1) and CBD (1 µmol L-1) both abolished the DMR response to LPI (10 µmol L-1). In murine iPSC cardiomyocytes, LPI-induced ROCK and p38 MAPK phosphorylation, both of which were prevented by Y-27632 and CBD, but did not induce JNK activation or cleavage of caspase-3. In hearts isolated from wild type (WT) mice subjected to 30 minutes global I/R, LPI (10 µmol L-1) administered via the coronary circulation increased infarct size when applied prior to ischemia onset, but not when given at the time of reperfusion. The exacerbation of tissue injury by LPI was not seen in hearts from GPR55-/- mice or in the presence of Y-27632, confirming that injury is mediated via the GPR55/ROCK/p38 MAPK pathway. These findings suggest that raised levels of LPI in the vicinity of a developing infarct may worsen the outcome of AMI.


Asunto(s)
Lisofosfolípidos/efectos adversos , Daño por Reperfusión Miocárdica/inducido químicamente , Receptores de Cannabinoides/metabolismo , Quinasas Asociadas a rho/metabolismo , Amidas/farmacología , Animales , Modelos Animales de Enfermedad , Ensayos Analíticos de Alto Rendimiento , Humanos , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/metabolismo , Masculino , Ratones , Daño por Reperfusión Miocárdica/metabolismo , Fosforilación/efectos de los fármacos , Piridinas/farmacología , Receptores de Cannabinoides/genética , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
14.
Neurol Res ; 30(10): 1030-8, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19079977

RESUMEN

OBJECTIVE: Despite the capacity for spontaneous axonal regeneration, recovery after severe peripheral nerve injury remains variable and often very poor. In addition, autologous nerve grafts, considered to be the 'gold standard' in nerve repair technique, are plagued by restricted donor tissue availability and donor site morbidity. Our primary objective is to highlight new and emerging methods of nerve repair, which have the potential to significantly improve both the functional and behavioral outcome after clinical nerve injury. METHODS: A critical analysis of nerve injury and regeneration literature concentrating on outcome measures from both immediate and chronically denervated experimental works was conducted. RESULTS: Results of numerous works employing both growth factor and stem cell enhanced nerve guidance conduits have shown encouraging results. However, further research is needed to optimize guidance conduit dynamics, bioavailability and delivery of both growth factors and stem cells to enhance peripheral nerve regeneration and functional recovery. DISCUSSION: This review discusses current animal and clinical growth factor and stem cell studies, specifically focusing on future bio-engineering approaches in developing a nerve guidance conduit in the future.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/uso terapéutico , Regeneración Nerviosa/fisiología , Traumatismos de la Médula Espinal/terapia , Células Madre/fisiología , Animales , Sistemas de Liberación de Medicamentos , Humanos , Regeneración Nerviosa/efectos de los fármacos , Traumatismos de la Médula Espinal/fisiopatología
15.
J Neurosci Methods ; 165(1): 83-8, 2007 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-17624441

RESUMEN

Despite the capacity for spontaneous axonal regeneration, recovery following injuries to the peripheral nervous system (PNS) following transection are often incomplete and limited to short distances. Nerve growth factor (NGF) has been previously shown to support neuron survival, and direct growth of both developing and regenerating nerve fibers along a concentration gradient, based largely on in vitro studies. Here, we present a novel in vivo model of administering daily concentration gradients of NGF by directly manipulating the placement of the catheter-nerve conduit junction. Our results show that a dose of 800 pg NGF can be reliably used to establish a chemotactic concentration gradient over both a transient time period, and chronically through repeated daily administrations of the drug. Results from these studies may lead to a better mechanistic understanding of how concentration gradients of soluble NGF influence in vivo peripheral nerve regeneration.


Asunto(s)
Factor de Crecimiento Nervioso/administración & dosificación , Regeneración Nerviosa/efectos de los fármacos , Animales , Axotomía , Cateterismo , Relación Dosis-Respuesta a Droga , Vías de Administración de Medicamentos , Humanos , Inyecciones , Masculino , Prótesis e Implantes , Ratas , Ratas Endogámicas Lew , Proteínas Recombinantes/administración & dosificación , Nervio Ciático/efectos de los fármacos
16.
JCO Clin Cancer Inform ; 1: 1-10, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-30657382

RESUMEN

PURPOSE: Evaluate rates of enrollment, completion, and patient-reported acceptability of an educational survivorship-care Web site for survivors of Hodgkin disease (HD). PATIENTS AND METHODS: The study was a mixed-method evaluation design. Eligible participants were adults who had completed treatment of a primary diagnosis of HD ≥ 2 years before enrollment. Patients were recruited through postal mail and telephone and were asked to review a Web site, complete an adapted version of the Acceptability E-scale (total score of 24 or greater indicates acceptability), and respond to a structured telephone or e-mail interview to discuss experiences with the Web site. RESULTS: Of 259 potentially eligible participants identified by medical record review, 124 survivors had confirmed contact with study staff and were invited to participate; 63 people (50.8%; 90% CI, 43% to 59%) enrolled; 37 participants (58.7%) were men. The median age at time of enrollment was 51.0 years (range, 29.3 to 80.0 years), and the median time since completion of treatment of HD was 14.9 years (range, 3 to 38.75 years). Overall, 82.5% of those enrolled viewed all Web site content. Forty-eight participants completed the acceptability survey, which resulted in a mean acceptability score of 26.5 (standard deviation, 3.5). The majority of enrollees (67%) completed a follow-up interview. CONCLUSION: Overall, HD survivor participants viewed the content and reviewed it favorably. A Web-based intervention is a promising way to provide survivors of HD with information about how to manage the long-term and late effects from cancer and treatment, and provide trusted survivorship resources.


Asunto(s)
Supervivientes de Cáncer , Promoción de la Salud , Enfermedad de Hodgkin/epidemiología , Supervivencia , Navegador Web , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Promoción de la Salud/métodos , Enfermedad de Hodgkin/diagnóstico , Enfermedad de Hodgkin/terapia , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias
17.
In Vitro Cell Dev Biol Anim ; 52(4): 395-409, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26714751

RESUMEN

A cell line (eelB) was developed from the outgrowth of adherent cells from brain explants of the American eel, Anguilla rostrata (Lesueur). EelB cells have been grown routinely in L-15 with 10% fetal bovine serum (FBS), undergone over 100 passages, and cryopreserved successfully. The cells from late-passage cultures (>45) were polygonal, formed capillary-like structures (CLS) on Matrigel, and stained immunocytochemically for von Willebrand factor (vWF) and for three tight junction proteins, zonula occludens-1 (ZO-1), claudin 3, and claudin 5. These results suggest that eelB is an endothelial cell line, one of the few from fish and the first from the brain. Despite this, eelB did not respond to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) with the induction of CYP1A protein. The cells from early-passage cultures (<20) had more varied shapes and did not form CLS on Matrigel. Only cells from early-passage cultures formed in suspension three-dimensional aggregates that had some cells expressing alkaline phosphatase and nestin. These cells are thought to be neural stem cells and the aggregates neurospheres. The emergence of endothelial-like cells upon the continued subcultivation of cells from early-passage cultures that had neural stem cells has been described previously for mammals, but this is a first for teleosts. Remarkably, cells from all passage levels were stained strongly for senescence-associated ß-galactosidase (SA ß-Gal) activity.


Asunto(s)
Encéfalo/citología , Línea Celular/citología , Anguilas/metabolismo , Células Endoteliales/citología , Animales , Capilares/metabolismo , Proliferación Celular , Forma de la Célula , Senescencia Celular , Cromosomas/metabolismo , Células Endoteliales/metabolismo , Inmunohistoquímica , Coloración y Etiquetado , Temperatura , Proteínas de Uniones Estrechas/metabolismo , Vimentina/metabolismo , beta-Galactosidasa/metabolismo
18.
Pharmacol Res Perspect ; 3(3): e00143, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26236485

RESUMEN

The receptors mediating the hemodynamic responses to cannabinoids are not clearly defined due to the multifarious pharmacology of many commonly used cannabinoid ligands. While both CB1 and TRPV1 receptors are implicated, G protein-coupled receptor 55 (GPR55) may also mediate some of the hemodynamic effects of several atypical cannabinoid ligands. The present studies attempted to unravel the pharmacology underlying the in vivo hemodynamic responses to ACEA (CB1 agonist), O-1602 (GPR55 agonist), AM251 (CB1 antagonist), and cannabidiol (CBD; GPR55 antagonist). Agonist and antagonist profiles of each ligand were determined by ligand-induced GTPγS binding in membrane preparations expressing rat and mouse CB1 and GPR55 receptors. Blood pressure responses to ACEA and O-1602 were recorded in anesthetized and conscious mice (wild type, CB1 (-/-) and GPR55(-/-)) and rats in the absence and presence of AM251 and CBD. ACEA demonstrated GTPγS activation at both receptors, while O-1602 only activated GPR55. AM251 exhibited antagonist activity at CB1 and agonist activity at GPR55, while CBD demonstrated selective antagonist activity at GPR55. The depressor response to ACEA was blocked by AM251 and attenuated by CBD, while O-1602 did not induce a depressor response. AM251 caused a depressor response that was absent in GPR55(-/-) mice but enhanced by CBD, while CBD caused a small vasodepressor response that persisted in GPR55(-/-) mice. Our findings show that assessment of the pharmacological profile of receptor activation by cannabinoid ligands in in vitro studies alongside in vivo functional studies is essential to understand the role of cannabinoids in hemodynamic control.

19.
PLoS One ; 9(9): e108999, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25275556

RESUMEN

G protein coupled receptor 55 (GPR55) is expressed throughout the body, and although its exact physiological function is unknown, studies have suggested a role in the cardiovascular system. In particular, GPR55 has been proposed as mediating the haemodynamic effects of a number of atypical cannabinoid ligands; however this data is conflicting. Thus, given the incongruous nature of our understanding of the GPR55 receptor and the relative paucity of literature regarding its role in cardiovascular physiology, this study was carried out to examine the influence of GPR55 on cardiac function. Cardiac function was assessed via pressure volume loop analysis, and cardiac morphology/composition assessed via histological staining, in both wild-type (WT) and GPR55 knockout (GPR55(-/-)) mice. Pressure volume loop analysis revealed that basal cardiac function was similar in young WT and GPR55(-/-) mice. In contrast, mature GPR55(-/-) mice were characterised by both significant ventricular remodelling (reduced left ventricular wall thickness and increased collagen deposition) and systolic dysfunction when compared to age-matched WT mice. In particular, the load-dependent parameter, ejection fraction, and the load-independent indices, end-systolic pressure-volume relationship (ESPVR) and Emax, were all significantly (P<0.05) attenuated in mature GPR55(-/-) mice. Furthermore, GPR55(-/-) mice at all ages were characterised by a reduced contractile reserve. Our findings demonstrate that mice deficient in GPR55 exhibit maladaptive adrenergic signalling, as evidenced by the reduced contractile reserve. Furthermore, with age these mice are characterised by both significant adverse ventricular remodelling and systolic dysfunction. Taken together, this may suggest a role for GPR55 in the control of adrenergic signalling in the heart and potentially a role for this receptor in the pathogenesis of heart failure.


Asunto(s)
Envejecimiento/patología , Eliminación de Gen , Contracción Miocárdica , Receptores Adrenérgicos/metabolismo , Receptores de Cannabinoides/deficiencia , Disfunción Ventricular/fisiopatología , Animales , Colágeno/metabolismo , Femenino , Hemodinámica , Masculino , Ratones , Receptores de Cannabinoides/metabolismo , Función Ventricular Izquierda
20.
Br J Pharmacol ; 168(5): 1074-85, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23186152

RESUMEN

Peroxisome proliferator activated receptors (PPARs) are ligand-activated transcription factors expressed in trophoblasts, which regulate both cell differentiation and proliferation. In recent years, evidence has linked PPARs to playing an integral role in pregnancy; specifically, PPAR-ß and PPAR-γ have been shown to play an integral role in placentation, with PPAR-γ additionally serving to regulate trophoblast differentiation. Recent evidence has shown that PPAR-γ expression is altered in many complications of pregnancy such as intrauterine growth restriction (IUGR), preterm birth, pre-clampsia and gestational diabetes. Thus, at present, accumulating evidence from the literature suggests both a pivotal role for PPAR-γ in the progression of a healthy pregnancy and the possibility that PPAR-γ may act as a therapeutic target in complicated pregnancies. This review aims to provide a succinct and comprehensive assessment of the role of PPAR-γ in normal pregnancy and pregnancy complications, and finally its potential as a therapeutic target in the treatment and/or prevention of adverse pregnancy outcomes.


Asunto(s)
PPAR gamma/metabolismo , Complicaciones del Embarazo/metabolismo , Embarazo/metabolismo , Animales , Femenino , Humanos , Complicaciones del Embarazo/prevención & control
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