Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 24
Filter
Add more filters










Publication year range
1.
Antiviral Res ; 183: 104935, 2020 11.
Article in English | MEDLINE | ID: mdl-32949636

ABSTRACT

Zika virus (ZIKV) outbreaks have been reported worldwide, including a recent occurrence in Brazil where it spread rapidly, and an association with increased cases of microcephaly was observed in addition to neurological issues such as GBS that were reported during previous outbreaks. Following infection of neuronal tissues, ZIKV can cause inflammation, which may lead to neuronal abnormalities, including seizures and paralysis. Therefore, a drug containing both anti-viral and immunosuppressive properties would be of great importance in combating ZIKV related neurological abnormalities. Castanospermine (CST) is potentially a right candidate drug as it reduced viral load and brain inflammation with the resulting appearance of delayed neuronal disorders, including seizures and paralysis in an Ifnar1-/- mouse.


Subject(s)
Antiviral Agents/therapeutic use , Indolizines/therapeutic use , Inflammation/drug therapy , Seizures/drug therapy , Seizures/virology , Zika Virus Infection/complications , Zika Virus Infection/drug therapy , Animals , Cell Line, Tumor , Chlorocebus aethiops , Disease Models, Animal , Female , Glioblastoma , Humans , Immunosuppressive Agents/therapeutic use , Inflammation/virology , Male , Mice , Seizures/immunology , Vero Cells , Viral Load/drug effects , Zika Virus/drug effects
2.
PLoS One ; 11(5): e0154208, 2016.
Article in English | MEDLINE | ID: mdl-27136924

ABSTRACT

Some species of butterflyfish have had preyed upon corals for millions of years, yet the mechanism of butterflyfish specialized coral feeding strategy remains poorly understood. Certain butterflyfish have the ability to feed on allelochemically rich soft corals, e.g. Sinularia maxima. Cytochrome P450 (CYP) is the predominant enzyme system responsible for the detoxification of dietary allelochemicals. CYP2-like and CYP3A-like content have been associated with butterflyfish that preferentially consumes allelochemically rich soft corals. To investigate the role of butterflyfish CYP2 and CYP3A enzymes in dietary preference, we conducted oral feeding experiments using homogenates of S. maxima and a toxin isolated from the coral in four species of butterflyfish with different feeding strategies. After oral exposure to the S. maxima toxin 5-episinulaptolide (5ESL), which is not normally encountered in the Hawaiian butterflyfish diet, an endemic specialist, Chaetodon multicinctus experienced 100% mortality compared to a generalist, Chaetodon auriga, which had significantly more (3-6 fold higher) CYP3A-like basal content and catalytic activity. The specialist, Chaetodon unimaculatus, which preferentially feed on S. maxima in Guam, but not in Hawaii, had 100% survival, a significant induction of 8-12 fold CYP3A-like content, and an increased ability (2-fold) to metabolize 5ESL over other species. Computer modeling data of CYP3A4 with 5ESL were consistent with microsomal transformation of 5ESL to a C15-16 epoxide from livers of C. unimaculatus. Epoxide formation correlated with CYP3A-like content, catalytic activity, induction, and NADPH-dependent metabolism of 5ESL. These results suggest a potentially important role for the CYP3A family in butterflyfish-coral diet selection through allelochemical detoxification.


Subject(s)
Adaptation, Physiological/drug effects , Anthozoa/metabolism , Diterpenes/toxicity , Environmental Exposure/adverse effects , Geography , Perciformes/physiology , Toxins, Biological/toxicity , Animals , Biotransformation/drug effects , Cytochrome P-450 Enzyme System/metabolism , Diterpenes/metabolism , Epoxy Compounds/metabolism , Microsomes/drug effects , Microsomes/metabolism , Perciformes/metabolism , Survival Analysis , Toxins, Biological/metabolism
3.
Article in English | MEDLINE | ID: mdl-26297807

ABSTRACT

Dietary specialists tend to be less susceptible to the effects of chemical defenses produced by their prey compared to generalist predators that feed upon a broader range of prey species. While many researchers have investigated the ability of insects to detoxify dietary allelochemicals, little research has been conducted in marine ecosystems. We investigated metabolic detoxification pathways in three species of butterflyfishes: the hard coral specialist feeder, Chaetodon multicinctus, and two generalist feeders, Chaetodon auriga and Chaetodon kleinii. Each species was fed tissue homogenate of the hard coral Porites lobata or the feeding deterrent compound homarine (found in the coral extract), and the expression and catalytic activity of cytochrome P450 (CYP) 3A-like and CYP2-like enzymes were examined after one-week of treatment. The P. lobata homogenate significantly induced content and catalytic activity of CYP2-like and CYP3A-like forms, by 2-3 fold and by 3-9 fold, respectively, in C. multicinctus. Homarine caused a significant decrease of CYP2-like and CYP3A-like proteins at the high dose in C. kleinii and 60-80% mortality in that species. Homarine also induced CYP3A-like content by 3-fold and catalytic activity by 2-fold in C. auriga, while causing non-monotonic increases in CYP2-like and CYP3A-like catalytic activity in C. multicinctus. Our results indicate that dietary exposure to coral homogenates and the feeding deterrent constituent within these homogenates caused species-specific modulation of detoxification enzymes consistent with the prey selection strategies of generalist and specialist butterflyfishes.


Subject(s)
Anthozoa , Cytochrome P-450 Enzyme System/biosynthesis , Feeding Behavior/drug effects , Microsomes, Liver/drug effects , Picolinic Acids/pharmacology , Animals , Cytochrome P-450 Enzyme System/genetics , Feeding Behavior/physiology , Gene Expression Regulation , Hawaii , Microsomes, Liver/metabolism , Perciformes , Picolinic Acids/isolation & purification
4.
Trends Genet ; 32(1): 1-15, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26686413

ABSTRACT

Transmissible tumors are those that have transcended the bounds of their incipient hosts by evolving the ability to infect another individual through direct transfer of cancer cells, thus becoming parasitic cancer clones. Coitus, biting, and scratching are transfer mechanisms for the two primary species studied, the domestic dog (Canis lupus familiaris) and the Tasmanian devil (Sarcophilus harrisii). Canine transmissible venereal tumors (CTVT) are likely thousands of years old, and have successfully travelled from host to host around the world, while the Tasmanian devil facial tumor disease (DFTD) is much younger and geographically localized. The dog tumor is not necessarily lethal, while the devil tumor has driven the population to near extinction. Transmissible tumors are uniform in that they have complex immunologic profiles, which allow them to escape immune detection by their hosts, sometimes for long periods of time. In this review, we explore how transmissible tumors in CTVT, DFTD, and as well as the soft-shell clam and Syrian hamster, can advance studies of tumor biology.


Subject(s)
Dog Diseases/transmission , Facial Neoplasms/veterinary , Neoplasms/veterinary , Venereal Tumors, Veterinary , Animals , Biological Evolution , Dogs , Genetic Variation , Marsupialia , Mesocricetus , Mya , Neoplasms/genetics , Neoplasms/immunology
5.
PLoS One ; 8(12): e77173, 2013.
Article in English | MEDLINE | ID: mdl-24324575

ABSTRACT

Coral bleaching is a significant contributor to the worldwide degradation of coral reefs and is indicative of the termination of symbiosis between the coral host and its symbiotic algae (dinoflagellate; Symbiodinium sp. complex), usually by expulsion or xenophagy (symbiophagy) of its dinoflagellates. Herein, we provide evidence that during the earliest stages of environmentally induced bleaching, heat stress and light stress generate distinctly different pathomorphological changes in the chloroplasts, while a combined heat- and light-stress exposure induces both pathomorphologies; suggesting that these stressors act on the dinoflagellate by different mechanisms. Within the first 48 hours of a heat stress (32°C) under low-light conditions, heat stress induced decomposition of thylakoid structures before observation of extensive oxidative damage; thus it is the disorganization of the thylakoids that creates the conditions allowing photo-oxidative-stress. Conversely, during the first 48 hours of a light stress (2007 µmoles m(-2) s(-1) PAR) at 25°C, condensation or fusion of multiple thylakoid lamellae occurred coincidently with levels of oxidative damage products, implying that photo-oxidative stress causes the structural membrane damage within the chloroplasts. Exposure to combined heat- and light-stresses induced both pathomorphologies, confirming that these stressors acted on the dinoflagellate via different mechanisms. Within 72 hours of exposure to heat and/or light stresses, homeostatic processes (e.g., heat-shock protein and anti-oxidant enzyme response) were evident in the remaining intact dinoflagellates, regardless of the initiating stressor. Understanding the sequence of events during bleaching when triggered by different environmental stressors is important for predicting both severity and consequences of coral bleaching.


Subject(s)
Anthozoa/radiation effects , Chloroplasts/radiation effects , Dinoflagellida/radiation effects , Intracellular Membranes/radiation effects , Animals , Chlorophyll/metabolism , Chloroplasts/ultrastructure , Coral Reefs , Dinoflagellida/ultrastructure , Gene Expression , Heat-Shock Proteins/genetics , Heat-Shock Proteins/metabolism , Hot Temperature , Intracellular Membranes/ultrastructure , Light , Microscopy, Electron, Transmission , Oxidation-Reduction , Oxidative Stress , Photolysis , Protozoan Proteins/genetics , Protozoan Proteins/metabolism , Stress, Physiological , Symbiosis , Temperature
6.
PLoS One ; 8(4): e61853, 2013.
Article in English | MEDLINE | ID: mdl-23613954

ABSTRACT

We have demonstrated that simple formulations composed of the parent drug in combination with generally regarded as safe (GRAS) permeability enhancers are capable of dramatically increasing the absolute bioavailability of zanamivir. This has the advantage of not requiring modification of the drug structure to promote absorption, thus reducing the regulatory challenges involved in conversion of an inhaled to oral route of administration of an approved drug. Absolute bioavailability increases of up to 24-fold were observed when Capmul MCM L8 (composed of mono- and diglycerides of caprylic/capric acids in glycerol) was mixed with 1.5 mg of zanamivir and administered intraduodenally to rats. Rapid uptake (t(max) of 5 min) and a C(max) of over 7200 ng/mL was achieved. Variation of the drug load or amount of enhancer demonstrated a generally linear variation in absorption, indicating an ability to optimize a formulation for a desired outcome such as a targeted C(max) for enzyme saturation. No absorption enhancement was observed when the enhancer was given 2 hr prior to drug administration, indicating, in combination with the observed tmax, that absorption enhancement is temporary. This property is significant and aligns well with therapeutic applications to limit undesirable drug-drug interactions, potentially due to the presence of other poorly absorbed polar drugs. These results suggest that optimal human oral dosage forms of zanamivir should be enteric-coated gelcaps or softgels for intraduodenal release. There continues to be a strong need and market for multiple neuraminidase inhibitors for influenza treatment. Creation of orally available formulations of inhibitor drugs that are currently administered intravenously or by inhalation would provide a significant improvement in treatment of influenza. The very simple GRAS formulation components and anticipated dosage forms would require low manufacturing costs and yield enhanced convenience. These results are being utilized to design prototype dosage forms for initial human pharmacokinetic studies.


Subject(s)
Cell Membrane Permeability , Influenza, Human/drug therapy , Influenza, Human/pathology , Orthomyxoviridae Infections/drug therapy , Orthomyxoviridae Infections/pathology , Zanamivir/pharmacokinetics , Zanamivir/therapeutic use , Absorption/drug effects , Administration, Oral , Animals , Biological Availability , Biological Transport/drug effects , Caco-2 Cells , Cell Membrane Permeability/drug effects , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/therapeutic use , Humans , Influenza, Human/virology , Male , Neuraminidase/antagonists & inhibitors , Neuraminidase/metabolism , Orthomyxoviridae Infections/virology , Rats , Rats, Sprague-Dawley , Time Factors , Zanamivir/administration & dosage , Zanamivir/pharmacology
7.
Article in English | MEDLINE | ID: mdl-22947416

ABSTRACT

An aqueous normal phase (ANP) liquid chromatography coupled with a hybrid quadrupole time-of-flight mass spectrometry (ANP-LC-micrOTOFQ) method was used for the determination of zanamivir in human serum. Zanamivir was extracted with methanol from protein-precipitated human serum samples and further purified with SCX solid-phase extraction cartridges. Scherzo SM-C18, Agilent Zorbax SB-Aq, Cogent Diamond Hydride, Cogent Bidentate and Luna HILIC columns were compared and optimized for the retention and separation of zanamivir and the Luna HILIC and Diamond Hydride columns exhibited the best retention of zanamivir. The former provided a shorter retention time, a sharper peak and relatively high sensitivity, whereas the latter exhibited a longer retention time and less matrix interference. The analytical range of the calibration curve was between 5 and 1000 ng/mL.


Subject(s)
Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods , Zanamivir/blood , Humans , Limit of Detection , Reproducibility of Results , Solid Phase Extraction , Zanamivir/chemistry
8.
Ecotoxicology ; 21(3): 768-82, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22215560

ABSTRACT

Coral reefs throughout the world are exhibiting documented declines in coral cover and species diversity, which have been linked to anthropogenic stressors including land-based sources of pollution. Reductions in coastal water and substratum quality are affecting coral survivorship, reproduction and recruitment, and hence, the persistence of coral reefs. One major obstacle in effectively addressing these declines is the lack of tools that can identify cause-and-effect relationships between stressors and specific coral reef losses, while a second problem is the inability to measure the efficacy of mitigation efforts in a timely fashion. We examined corals from six coral reefs on Guam, Mariana Islands, which were being affected by different environmental stressors (e.g. PAH's, pesticides, PCB's and sedimentation). Cellular diagnostic analysis differentiated the cellular-physiological condition of these corals. Examination of protein expression provided insight into their homeostatic responses to chemical and physical stressors in exposed corals prior to outright mortality, providing improved opportunities for developing locally-based management responses. This approach adds critically needed tools for addressing the effects of multiple stressors on corals and will allow researchers to move beyond present assessment and monitoring techniques that simply document the loss of coral abundance and diversity.


Subject(s)
Anthozoa/drug effects , Anthozoa/physiology , Coral Reefs , Water Pollutants, Chemical/toxicity , Xenobiotics/toxicity , Animals , Anthozoa/metabolism , Biomarkers/metabolism , Environmental Exposure , Environmental Monitoring , Gene Expression/drug effects , Inactivation, Metabolic/genetics , Oxidative Stress/drug effects , Oxidative Stress/genetics , Population Dynamics , Proteins/genetics , Proteins/metabolism , Water Pollutants, Chemical/classification , Water Pollutants, Chemical/pharmacokinetics , Xenobiotics/classification , Xenobiotics/pharmacokinetics
9.
Article in English | MEDLINE | ID: mdl-22008093

ABSTRACT

Coral reefs worldwide have become increasingly affected by a phenomenon known as "coral bleaching," the loss of the symbiotic algae from the host corals. The underlying causes and mechanism(s) of coral bleaching are not well known, although several have been hypothesized. While coral bleaching has been a primary focus in recent years, corals respond differentially to numerous environmental stresses. The impacts of heat, hydrocarbons, salinity, sewage effluents, biocides, heavy metals, and ultraviolet light have been investigated in both laboratory experiments and field surveys among multiple coral species. Herein what is known regarding the biological impacts of such stresses on corals at the molecular level of organization is summarized. The objective is to focus attention at the early stages of biological effects in order to encourage and facilitate research that provide ways to understand how changes at the molecular level might elucidate processes likely occurring at the population level. This, in turn, should accelerate studies that may elucidate the cellular and physiological changes contributing to coral decline, rather than just document the continued global loss of coral diversity and abundance.


Subject(s)
Anthozoa/drug effects , Ecotoxicology/methods , Environmental Monitoring , Environmental Pollutants/adverse effects , Molecular Biology , Animals , Anthozoa/physiology , Environmental Pollutants/metabolism , Fishes/genetics , Pigmentation/drug effects , Sea Anemones/genetics , Sequence Analysis, Protein , Signal Transduction , Species Specificity , Urochordata/genetics
10.
Ecotoxicology ; 20(8): 1914-31, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21735126

ABSTRACT

Coral communities along the coast of St. John, U.S. Virgin Islands have exhibited site-specific behavior in declines. In order to determine if these specific coral communities are stressed and whether a pollutant or environmental factor present at this site is a probable stressor, we surveyed six near-shore coral communities in St. John, USVI for environmental pollutants and to determine the cellular physiological condition of the coral, Porites astreoides. The six sites within St. John are Cruz Bay, Caneel Bay, Hawksnest Bay, Trunk Bay, Tektite Reef in Beehive Bay, and Red Point. Red Point was considered the reference site because of its abundance and diversity of species, and it was the furthest removed from down-stream and down-current anthropogenic activities. All sites showed distinct cellular-stress marker patterns, indicating that the physiological condition of each population was different. Populations at Cruz, Hawksnest, Trunk, and Tektite were stressed, as indicated by high levels of DNA lesions and expression of stress proteins. Hawksnest and Tektite were contaminated with polyaromatic hydrocarbons (PAHs), while Cruz was contaminated with semi-volatile organochlorines and nitrogen-based biocides. At least for Hawksnest and Tektite, stress-marker patterns were consistent with an exposure to PAHs. Fecal coliform levels were high in Cruz and Trunk, indicating fecal contamination, as well as consideration for management action. Results from this study serve as a justification for a more thorough and methodical investigation into the stressors responsible for declines of coral populations within St. John. Furthermore, this study supports the argument for the importance of local factors contributing to regional coral reef declines; that not all forces impacting coral are global.


Subject(s)
Anthozoa/physiology , Biomarkers/analysis , Environmental Pollutants/analysis , Animals , Anthozoa/drug effects , Anthozoa/genetics , DNA Damage , Data Collection , Ecosystem , Enterobacteriaceae , Feces/microbiology , Geologic Sediments/chemistry , Polycyclic Aromatic Hydrocarbons/analysis , Porphyrins/metabolism , United States Virgin Islands , Water Microbiology , Water Pollutants, Chemical/analysis , Water Pollution , Xenobiotics/toxicity
11.
Ecotoxicology ; 19(1): 171-84, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19757033

ABSTRACT

The logistics involved in obtaining and maintaining large numbers of corals hampers research on the toxicological effects of environmental contaminants for this ecologically and economically important taxon. A method for creating and culturing single-cell suspensions of viable coral cells was developed. Cell segregation/separation was based on specific cell densities and resulting cell cultures were viable for at least 2 mos. Low-density cells lacking symbiotic zooxanthallae and rich in mitochondria were isolated and cultured for toxicity studies. Cells were exposed to differing degrees or concentrations of heat stress, rotenone, cyanide, sulfide, and cuprous oxide. Cells were assayed for mitochondrial membrane potential using the fluorescent probe, JC-9, and for overall viability using the MTT/formazan spectrophotometric viability assay. Significant differences were observed between controls and treatments and the efficacy of this method was validated; only 2 cm(2) of tissue was required for a seven-point concentration-exposure series.


Subject(s)
Anthozoa/drug effects , Environmental Pollutants/toxicity , Mitochondria/drug effects , Models, Animal , Analysis of Variance , Animals , Cell Survival/drug effects , Cells, Cultured , Copper/toxicity , Fluorescent Dyes , Formazans , Hot Temperature , Membrane Potential, Mitochondrial/drug effects , Mitochondria/metabolism , Potassium Cyanide/toxicity , Rotenone/toxicity , Sulfides/toxicity , Tetrazolium Salts , Toxicity Tests/methods
12.
Annu Rev Genomics Hum Genet ; 10: 407-29, 2009.
Article in English | MEDLINE | ID: mdl-19630564

ABSTRACT

Performance enhancing polymorphisms (PEPs) are examples of natural genetic variation that affect the outcome of athletic challenges. Elite athletes, and what separates them from the average competitor, have been the subjects of discussion and debate for decades. While training, diet, and mental fitness are all clearly important contributors to achieving athletic success, the fact that individuals reaching the pinnacle of their chosen sports often share both physical and physiological attributes suggests a role for genetics. That multiple members of a family often participate in highly competitive events, such as the Olympics, further supports this argument. In this review, we discuss what is known regarding the genes and gene families, including the mitochondrial genome, that are believed to play a role in human athletic performance. Where possible, we describe the physiological impact of the critical gene variants and consider predictions about other potentially important genes. Finally, we discuss the implications of these findings on the future for competitive athletics.


Subject(s)
Athletic Performance , Genetic Variation , Sports/physiology , DNA, Mitochondrial/genetics , Doping in Sports , Humans , Muscle, Skeletal/anatomy & histology , Muscle, Skeletal/metabolism , Phenotype
13.
Sci Total Environ ; 407(17): 4838-51, 2009 Aug 15.
Article in English | MEDLINE | ID: mdl-19515401

ABSTRACT

Coral reefs can experience extreme salinity changes, particularly hypo-salinity, as a result of storms, heavy rainy seasons (e.g., monsoons), and coastal runoff. Field and laboratory observations have documented that corals exposed to hypo-saline conditions can undergo extensive bleaching and mortality. There is controversy in the literature as to whether hypo-saline conditions induce a pathological response in corals, and if there is a relationship between decreasing salinity treatment and pathological responses. To test the hypothesis that hypo-salinity exposure does not have a pathological effect on coral, we used histological and cellular diagnostic methods to characterize the pathology in hypo-salinity-exposed corals. Colonies of Stylophora pistillata were exposed to five salinity concentrations [39 parts per thousand (ppt), 32 ppt, 28 ppt, 24 ppt, and 20 ppt] that may realistically occur on a reef. Histological examination indicated an increasing severity of pathomorphologies associated with decreasing salinity, including increased tissue swelling, degradation and loss of zooxanthellae, and tissue necrosis. Pulse-amplitude modulated chlorophyll fluorimetry kinetics demonstrated a decreasing photosynthetic efficiency with decreasing salinity conditions. Cytochrome P450 levels were affected by even slight changes in salinity concentration suggesting that detoxification pathways, as well as several endocrine pathways, may be adversely affected. Finally, these studies demonstrated that hypo-saline conditions can induce an oxidative-stress response in both the host and in its algal symbiont, and in so doing, may synergistically increase oxidative-stress burdens. As with other types of environmental stresses, exposure to hypo-saline conditions may have long-term consequences on coral physiology.


Subject(s)
Anthozoa , Sodium Chloride , Animals , Blotting, Western , Electrophoresis, Polyacrylamide Gel , Environmental Exposure , Enzyme-Linked Immunosorbent Assay
14.
Comp Biochem Physiol C Toxicol Pharmacol ; 149(2): 134-40, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18835587

ABSTRACT

Retinoblastoma, a tumor suppressor gene, is frequently mutated in diverse types of human tumors. We have previously shown that two types of fish tumor, eye and liver, also possess mutant Rb genes. Our aim is to determine if the Rb allele status is linked to environmentally-induced cancer and whether this information in fish can be used to predict future phenotype. This is a proof-of-concept investigation to elucidate if fish may act as surrogates in assessing pollution-induced tumor incidence and inform regulatory authorities of potential long-term population health consequences. Marine flatfish, Limanda limanda, that display either normal liver histopathology, liver adenoma or liver hepatocellular carcinoma were analysed for the presence of Rb gene alterations. Several Rb alterations were detected in the fish displaying adenoma and carcinoma, and not in the surrounding normal tissue from the same individuals. The profile is similar to that reported in humans in that they spread across the gene, particularly exons 8-23, and a functionally important region of the protein. This Rb allele data was then used to build statistical classifier sets, linking Rb status with tumor pathology. Further flatfish caught from coastal-water areas of differing contaminant burden around the UK were subsequently analysed for the presence of Rb alterations. Using novel pattern matching statistics of the classifier sets compared with the coastal samples, the coastal fish were considered more similar to the characterised disease phenotype than the normal phenotype. Preliminary data suggests that using a statistical approach, based on classifying sets of histopathologically-defined tumor states, makes it possible to predict the phenotype of wild fish based on the status of the Rb allele. Since the Rb gene is orthologous, fish populations could act as surrogates for human populations in an eco-epidemiological investigation of the combined roles of genetics and environmental exposures in the tumorigenesis process.


Subject(s)
Carcinoma, Hepatocellular/genetics , Flatfishes/genetics , Genes, Retinoblastoma , Liver Neoplasms/genetics , Population Groups/genetics , Retinoblastoma/genetics , Animals , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Flatfishes/metabolism , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Mutation , Retinoblastoma/pathology
15.
Autophagy ; 5(2): 211-6, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19066451

ABSTRACT

Coral bleaching is a major contributor to the global declines of coral reefs. This phenomenon is characterized by the loss of symbiotic algae, their pigments or both. Despite wide scientific interest, the mechanisms by which bleaching occurs are still poorly understood. Here we report that the removal of the symbiont during light and temperature stress is achieved using the host's cellular autophagic-associated machinery. Host cellular and subcellular morphologies showed increased vacuolization and appearance of autophagic membranes surrounding a variety of organelles and surrounding the symbiotic algae. Markers of autophagy (Rab 7 and LAS) corroborate these observations. Results showed that during stress the symbiont vacuolar membrane is transformed from a conduit of nutrient exchange to a digestive organelle resulting in the consumption of the symbiont, a process we term symbiophagy. We posit that during a stress event, the mechanism maintaining symbiosis is destabilized and symbiophagy is activated, ultimately resulting in the phenomenon of bleaching. Symbiophagy may have evolved from a more general primordial innate intracellular protective pathway termed xenophagy.


Subject(s)
Anthozoa/cytology , Anthozoa/metabolism , Autophagy , Symbiosis , Animals , Anthozoa/radiation effects , Anthozoa/ultrastructure , Autophagy/radiation effects , Biomarkers/metabolism , Endoderm/radiation effects , Endoderm/ultrastructure , Eukaryota/radiation effects , Eukaryota/ultrastructure , Light , Symbiosis/radiation effects , Temperature
16.
Dis Aquat Organ ; 77(2): 127-35, 2007 Sep 14.
Article in English | MEDLINE | ID: mdl-17972754

ABSTRACT

Goldfish Carassius auratus are common aquarium fish and have a significant economic and research value, having considerable worth to fisheries as a baitfish and the ability to adapt to a range of habitats. Two cell lines were established from goldfish muscle and swim bladder tissue, in order to create a biological monitoring tool for viral diseases. Cell lines were optimally maintained at 30 degrees C in Leibovitz-15 medium supplemented with 20% fetal bovine serum. Propagation of goldfish cells was serum dependent, with a low plating efficiency (>16%). Karyotyping analysis indicated that both cell lines remained diploid, with a mean chromosomal count of 104. Results of viral challenge assays revealed that both cell lines shared similar patterns of viral susceptibility and production to infectious hematopoietic necrosis virus, infectious pancreatic necrosis virus, snakehead rhabdovirus, and spring viremia carp virus. Both cell lines demonstrated a higher sensitivity and significantly larger viral production than control brown bullhead cells for channel catfish virus. These newly established cell lines will be used as a diagnostic tool for viral diseases in this fish species and also for the isolation and study of goldfish viruses in the future.


Subject(s)
Disease Susceptibility/veterinary , Fish Diseases/virology , Goldfish/virology , Virus Diseases/veterinary , Viruses/pathogenicity , Air Sacs/cytology , Air Sacs/virology , Animals , Base Sequence , Cell Line , Chromosomes , Cryopreservation/veterinary , Disease Susceptibility/virology , Fish Diseases/immunology , Host-Pathogen Interactions , Molecular Sequence Data , Muscles/cytology , Muscles/virology , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 18S/genetics , Temperature , Time Factors , Virus Diseases/immunology , Virus Diseases/virology
17.
Genetica ; 129(3): 227-33, 2007 Mar.
Article in English | MEDLINE | ID: mdl-16897464

ABSTRACT

Terminal ends of vertebrate chromosomes are protected by tandem repeats of the sequence (TTAGGG). First thought to be vertebrate specific, (TTAGGG)( n ) has recently been identified in several aquatic invertebrates including sea urchin (Strongylocentrotus purpuratus), bay scallop (Argopecten irradians), and wedgeshell clam (Donax trunculus). We analyzed genomic DNA from scleractinian corals, Acropora surculosa, Favia pallida, Leptoria phrygia, and Goniastrea retiformis to determine the telomere sequence. Southern blot analysis suggests the presence of the vertebrate telomere repeats in all four species. Treatment of A. surculosa sperm DNA with Bal31 exonuclease revealed progressive shortening of the DNA fragments positive for the (TTAGGG)(22) sequence, supporting location of the repeats at the chromosome ends. The presence of the vertebrate telomere repeats in corals is evidence that the (TTAGGG)( n ) sequence is highly conserved among a divergent group of vertebrate and invertebrate species. Corals are members of the Lower Metazoans, the group of organisms that span the gap between the fungi and higher metazoans. Corals are the most basal organism reported to have the (TTAGGG)( n ) sequence to date, which suggests that the vertebrate telomere sequence may be much older than previously thought and that corals may share a number of genes with their higher relatives.


Subject(s)
Anthozoa/genetics , Tandem Repeat Sequences/genetics , Telomere/genetics , Animals , Blotting, Southern , Conserved Sequence/genetics , Endodeoxyribonucleases , Guam , Species Specificity
18.
Environ Toxicol Chem ; 25(12): 3171-80, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17220086

ABSTRACT

The grounding of the Merchant Vessel (MV) Kyowa Violet on a coral reef near Yap, Federated States of Micronesia, in December 2002 resulted in the release of an estimated 55,000 to 80,000 gallons of intermediate fuel oil grade 180. The immediate impact was the widespread coating of mangroves and the intertidal zone along more than 8 km of coastline. Of greater concern, however, was the partitioning of the fuel oil in the water column, leading to chronic exposure of organisms in the ecosystem for a considerable period after the initial event. Herein, we report on our examination of one coral species, Porites lobata, nearly three months after the initial exposure. We investigated whether changes in cellular physiology were consistent with the pathological profile that results from the interaction of corals with polycyclic aromatic hydrocarbons, the principal constituent of fuel oil. Specifically, we document, to our knowledge for the first time, changes in the cellular physiological condition of an exposed coral population affected by a fuel-oil spill. We also provide evidence that the observed changes are consistent with a recent exposure to fuel oil, as evidenced by the presence of characteristic cellular lesions attributed to polycyclic aromatic hydrocarbons. Finally, our data support a model for a mechanistic relationship between the cellular pathological profile of the coral and a recent petroleum exposure, such as the MV Kyowa Violet fuel oil spill.


Subject(s)
Anthozoa/drug effects , Cell Physiological Phenomena/drug effects , Fuel Oils , Water Pollutants, Chemical/pharmacology , Animals , Anthozoa/metabolism , Biomarkers , Enzyme-Linked Immunosorbent Assay , Micronesia
19.
Environ Toxicol Chem ; 25(12): 3181-7, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17220087

ABSTRACT

Petroleum contamination from oil spills is a continuing threat to our ocean's fragile ecosystems. Herein, we explored the effects of the water-soluble fraction of crude oil on a stony coral, Pocillopora damicornis (Linneaeus 1758). We developed methods for exposing corals to various concentrations of crude oil and for assessing the potential molecular responses of the corals. Corals were exposed to water-accommodated fraction solutions, and appropriate cellular biomarkers were quantified. When compared to the "healthy" control specimens, exposed corals exhibited shifts in biomarker concentrations that were indicative of a shift from homeostasis. Significant changes were seen in cytochrome P450 1-class, cytochrome P450 2-class, glutathione-S-transferase-pi, and cnidarian multixenobiotic resistance protein- biomarkers, which are involved the cellular response to, and manipulation and excretion of, toxic compounds, including polycyclic aromatic hydrocarbons. A shift in biomarkers necessary for porphyrin production (e.g., protoporphyrinogen oxidase IX and ferrochelatase) and porphyrin destruction (e.g., heme oxygenase-1 and invertebrate neuroglobin homologue) illustrates only one of the cellular protective mechanisms. The response to oxidative stress was evaluated through measurements of copper/zinc superoxide dismutase-1 and DNA glycosylase MutY homologue-1 concentrations. Likewise, changes in heat shock protein 70 and small heat shock proteins indicated an adjustment in the cellular production of proteins. Finally, the results of this laboratory study were nearly identical to what we observed previously among corals of a different species, Porites lobata, exposed to an oil spill in the field after the grounding of the Merchant Vessel Kyowa Violet.


Subject(s)
Anthozoa/drug effects , Fuel Oils , Animals , Anthozoa/metabolism , Biomarkers , Oxidative Stress , Porphyrins/metabolism , Porphyrins/pharmacology , Proteins/metabolism , Xenobiotics/pharmacology
20.
Cancer Res ; 64(23): 8485-91, 2004 Dec 01.
Article in English | MEDLINE | ID: mdl-15574750

ABSTRACT

The promotion of crude shark cartilage extracts as a cure for cancer has contributed to at least two significant negative outcomes: a dramatic decline in shark populations and a diversion of patients from effective cancer treatments. An alleged lack of cancer in sharks constitutes a key justification for its use. Herein, both malignant and benign neoplasms of sharks and their relatives are described, including previously unreported cases from the Registry of Tumors in Lower Animals, and two sharks with two cancers each. Additional justifications for using shark cartilage are illogical extensions of the finding of antiangiogenic and anti-invasive substances in cartilage. Scientific evidence to date supports neither the efficacy of crude cartilage extracts nor the ability of effective components to reach and eradicate cancer cells. The fact that people think shark cartilage consumption can cure cancer illustrates the serious potential impacts of pseudoscience. Although components of shark cartilage may work as a cancer retardant, crude extracts are ineffective. Efficiencies of technology (e.g., fish harvesting), the power of mass media to reach the lay public, and the susceptibility of the public to pseudoscience amplifies the negative impacts of shark cartilage use. To facilitate the use of reason as the basis of public and private decision-making, the evidence-based mechanisms of evaluation used daily by the scientific community should be added to the training of media and governmental professionals. Increased use of logical, collaborative discussion will be necessary to ensure a sustainable future for man and the biosphere.


Subject(s)
Fish Diseases/epidemiology , Neoplasms/epidemiology , Neoplasms/veterinary , Sharks , Animals , Cartilage/chemistry , Complementary Therapies , Disease Susceptibility , Fish Diseases/pathology , Incidence , Neoplasms/pathology , Neoplasms/therapy , Tissue Extracts/therapeutic use
SELECTION OF CITATIONS
SEARCH DETAIL
...