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1.
Am J Physiol Gastrointest Liver Physiol ; 321(1): G1-G10, 2021 07 01.
Article in English | MEDLINE | ID: mdl-33950707

ABSTRACT

Recent advances in intestinal organoid research, along with encouraging preclinical proof-of-concept studies, have revealed significant therapeutic potential for induced pluripotent stem cell (iPSC)-derived organoids in the healing and replacement of severely injured or diseased bowel (Finkbeiner et al. Biol Open 4: 1462-1472, 2015; Kitano et al. Nat Commun 8: 765, 2017; Cruz-Acuna et al. Nat Cell Biol 19: 1326-1335, 2017). To fully realize the tremendous promise of stem cell organoid-based therapies, careful planning aligned with significant resources and efforts must be devoted demonstrating their safety and efficacy to meet critical regulatory requirements. Early recognition of the inherent preclinical and clinical obstacles that occur with the novel use of pluripotent stem cell-derived products will accelerate their bench-to-bedside translation (Neofytou et al. J Clin Invest 125: 2551-2557, 2015; O'Brien et al. Stem Cell Res Ther 6: 146, 2015; Ouseph et al. Cytotherapy 17: 339-343, 2015). To overcome many of these hurdles, a close and effective collaboration is needed between experts from various disciplines, including basic and clinical research, product development and manufacturing, quality assurance and control, and regulatory affairs. Therefore, the purpose of this article is to outline the critical areas and challenges that must be addressed when transitioning laboratory-based discovery, through an investigational new drug (IND) application to first-in-human clinical trial, and to encourage investigators to consider the required regulatory steps from the earliest stage of the translational process. The ultimate goal is to provide readers with a draft roadmap that they could use while navigating this exciting cell therapy space.


Subject(s)
Cell- and Tissue-Based Therapy , Drug Development , Intestines/cytology , Organoids/transplantation , Pluripotent Stem Cells/cytology , Cell- and Tissue-Based Therapy/methods , Drug Development/methods , Humans , Intestines/transplantation , Organoids/cytology , Research
2.
Autophagy ; 17(10): 3124-3139, 2021 10.
Article in English | MEDLINE | ID: mdl-33249983

ABSTRACT

The ubiquitin-proteasome system (UPS) and autophagy-lysosomal pathway (ALP) are two major protein degradation pathways in eukaryotic cells. Initially considered as two independent pathways, there is emerging evidence that they can work in concert. As alterations of UPS and ALP function can contribute to neurodegenerative disorders, cancer and cardiac disease, there is great interest in finding targets that modulate these catabolic processes. We undertook an unbiased, total genome high-throughput screen to identify novel effectors that regulate both the UPS and ALP. We generated a stable HEK293 cell line expressing a UPS reporter (UbG76V-mCherry) and an ALP reporter (GFP-LC3) and screened for genes for which knockdown increased both UbG76V-mCherry intensity and GFP-LC3 puncta. With stringent selection, we isolated 80 candidates, including the transcription factor ZNF418 (ZFP418 in rodents). After screen validation with Zfp418 overexpression in HEK293 cells, we evaluated Zfp418 knockdown and overexpression in neonatal rat ventricular myocytes (NRVMs). Endogenous and overexpressed ZFP418 were localized in the nucleus. Subsequent experiments showed that ZFP418 negatively regulates UPS and positively regulates ALP activity in NRVMs. RNA-seq from Zfp418 knockdown revealed altered gene expression of numerous ubiquitinating and deubiquitinating enzymes, decreased expression of autophagy activators and initiators and increased expression of autophagy inhibitors. We found that ZPF418 activated the promoters of Dapk2 and Fyco1, which are involved in autophagy. RNA-seq from Zfp418 knockdown revealed accumulation of several genes involved in cardiac development and/or hypertrophy. In conclusion, our study provides evidence that ZNF418 activates the ALP, inhibits the UPS and regulates genes associated with cardiomyocyte structure/function.Abbreviations: ACTN2, actinin alpha 2; ALP, autophagy-lysosomal pathway; COPB1, COPI coat complex subunit beta 1; DAPK2, death associated protein kinase 2; FYCO1, FYVE and coiled-coil domain autophagy adaptor 1; HEK293, human embryonic kidney cells 293; HTS, high-throughput screen; LC3, microtubule associated protein 1 light chain 3; NRVMs, neonatal rat ventricular myocytes; RNA-seq, RNA sequencing; RPS6, ribosomal protein S6; TNNI3, troponin I, cardiac 3; UPS, ubiquitin-proteasome system; shRNA, short hairpin RNA; SQSTM1/p62, sequestosome 1; VPS28, VPS28 subunit of ESCRT-I; ZNF418/ZFP418, zinc finger protein 418.


Subject(s)
Proteasome Endopeptidase Complex , Repressor Proteins , Ubiquitin , Animals , Autophagy/genetics , HEK293 Cells , High-Throughput Screening Assays , Humans , Lysosomes/metabolism , Proteasome Endopeptidase Complex/metabolism , Rats , Repressor Proteins/metabolism , Ubiquitin/metabolism
3.
Am J Physiol Renal Physiol ; 316(6): F1293-F1298, 2019 06 01.
Article in English | MEDLINE | ID: mdl-31017009

ABSTRACT

Fibrosis is a common feature of chronic kidney disease; however, no clinical therapies effectively target the progression of fibrosis. Inhibition of fibronectin polymerization with the small peptide pUR4 attenuates fibrosis in the liver and heart. Here, we show that pUR4 decreases renal fibrosis and tissue remodeling using a clinically relevant model of kidney injury, unilateral ischemia-reperfusion. This work highlights the benefits of inhibiting matrix polymerization, alone or in conjunction with cell-based therapies, as a novel approach to diminish the maladaptive responses to ischemic kidney injury that lead to chronic renal failure.


Subject(s)
Acute Kidney Injury/prevention & control , Extracellular Matrix/drug effects , Fibronectins/metabolism , Kidney/drug effects , Peptide Fragments/pharmacology , Reperfusion Injury/prevention & control , Acute Kidney Injury/metabolism , Acute Kidney Injury/pathology , Animals , Disease Models, Animal , Extracellular Matrix/metabolism , Extracellular Matrix/pathology , Fibrosis , Kidney/metabolism , Kidney/pathology , Male , Mice, Inbred C57BL , Polymerization , Reperfusion Injury/metabolism , Reperfusion Injury/pathology
4.
Bone Marrow Transplant ; 53(1): 34-38, 2018 01.
Article in English | MEDLINE | ID: mdl-29084203

ABSTRACT

Single-agent high-dose melphalan (HDM, 200 mg/m2) has been the most commonly used conditioning regimen prior to autologous stem cell transplant, since its introduction in 1992. We used a more aggressive alkylator-based conditioning regimen in an attempt to overcome early relapse and combat drug resistance. We present a retrospective comparison and long-term follow-up of newly diagnosed patients with multiple myeloma (MM) treated with induction followed by either high-dose carmustine (BCNU) and HDM, or HDM alone, both followed by autologous stem cell transplant (ASCT). Between 1997 and 2002, 104 patients were treated with BCNU/HDM; from 2001 to 2008, 103 patients were treated with HDM alone. Median follow-up of survivors was 78 and 68 months for the BCNU/HDM and HDM groups, respectively. The median PFS was significantly increased with the BCNU/HDM regimen (40.4 vs 20.5 months, P<0.001). Median overall survival was increased with the BCNU/HDM regimen when compared with HDM alone (88.4 vs 67.2 months, P=0.07), but the difference was not statistically significant. Transplant-related mortality was similar in both groups (2.9% with BCNU and HDM vs 3.9% with HDM alone). Our findings suggest that the BCNU/HDM preparative regimen should be investigated further and potentially compared in a prospective randomized manner with HDM alone.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carmustine/therapeutic use , Hematopoietic Stem Cell Transplantation/methods , Melphalan/therapeutic use , Multiple Myeloma/drug therapy , Transplantation Conditioning/methods , Transplantation, Autologous/methods , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Carmustine/pharmacology , Female , Humans , Male , Melphalan/pharmacology , Middle Aged , Multiple Myeloma/pathology , Retrospective Studies
5.
J Immunol ; 195(6): 2683-95, 2015 Sep 15.
Article in English | MEDLINE | ID: mdl-26268651

ABSTRACT

The production of mature eosinophils (Eos) is a tightly orchestrated process with the aim to sustain normal Eos levels in tissues while also maintaining low numbers of these complex and sensitive cells in the blood. To identify regulators of homeostatic eosinophilopoiesis in mice, we took a global approach to identify genome-wide transcriptome and epigenome changes that occur during homeostasis at critical developmental stages, including Eos-lineage commitment and lineage maturation. Our analyses revealed a markedly greater number of transcriptome alterations associated with Eos maturation (1199 genes) than with Eos-lineage commitment (490 genes), highlighting the greater transcriptional investment necessary for differentiation. Eos-lineage-committed progenitors (EoPs) were noted to express high levels of granule proteins and contain granules with an ultrastructure distinct from that of mature resting Eos. Our analyses also delineated a 976-gene Eos-lineage transcriptome that included a repertoire of 56 transcription factors, many of which have never previously been associated with Eos. EoPs and Eos, but not granulocyte-monocyte progenitors or neutrophils, expressed Helios and Aiolos, members of the Ikaros family of transcription factors, which regulate gene expression via modulation of chromatin structure and DNA accessibility. Epigenetic studies revealed a distinct distribution of active chromatin marks between genes induced with lineage commitment and genes induced with cell maturation during Eos development. In addition, Aiolos and Helios binding sites were significantly enriched in genes expressed by EoPs and Eos with active chromatin, highlighting a potential novel role for Helios and Aiolos in regulating gene expression during Eos development.


Subject(s)
DNA-Binding Proteins/genetics , Eosinophils/cytology , Hematopoiesis/genetics , Trans-Activators/genetics , Transcription Factors/genetics , Transcriptome/genetics , Animals , Binding Sites/genetics , Cell Lineage/genetics , Cell Lineage/immunology , Cells, Cultured , Chromatin/genetics , Cytoplasmic Granules/metabolism , Eosinophils/immunology , Gene Expression Regulation/genetics , Granulocyte Precursor Cells , Hematopoiesis/immunology , Ikaros Transcription Factor , Mice , Mice, Inbred BALB C , Transcription Factors/biosynthesis
6.
Dev Cell ; 32(5): 574-88, 2015 Mar 09.
Article in English | MEDLINE | ID: mdl-25703348

ABSTRACT

Gametogenesis is dependent on the expression of germline-specific genes. However, it remains unknown how the germline epigenome is distinctly established from that of somatic lineages. Here we show that genes commonly expressed in somatic lineages and spermatogenesis-progenitor cells undergo repression in a genome-wide manner in late stages of the male germline and identify underlying mechanisms. SCML2, a germline-specific subunit of a Polycomb repressive complex 1 (PRC1), establishes the unique epigenome of the male germline through two distinct antithetical mechanisms. SCML2 works with PRC1 and promotes RNF2-dependent ubiquitination of H2A, thereby marking somatic/progenitor genes on autosomes for repression. Paradoxically, SCML2 also prevents RNF2-dependent ubiquitination of H2A on sex chromosomes during meiosis, thereby enabling unique epigenetic programming of sex chromosomes for male reproduction. Our results reveal divergent mechanisms involving a shared regulator by which the male germline epigenome is distinguished from that of the soma and progenitor cells.


Subject(s)
Epigenomics , Gene Expression Regulation, Developmental , Histones/metabolism , Polycomb Repressive Complex 1/metabolism , Testis/metabolism , Ubiquitin/metabolism , Adaptor Proteins, Signal Transducing , Animals , Biomarkers/metabolism , Blotting, Western , Cell Cycle Proteins , Cells, Cultured , Chromatin Immunoprecipitation , Chromosomal Proteins, Non-Histone , Female , Gene Expression Profiling , Gene Silencing , Germ Cells , Immunoenzyme Techniques , Intracellular Signaling Peptides and Proteins/physiology , Male , Meiosis/genetics , Mice , Mice, Knockout , Oligonucleotide Array Sequence Analysis , Polycomb Repressive Complex 1/genetics , Polycomb Repressive Complex 1/physiology , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Repressor Proteins/physiology , Reverse Transcriptase Polymerase Chain Reaction , Sex Chromosomes/genetics , Spermatogenesis , Testis/cytology , Ubiquitin-Protein Ligases/physiology , Ubiquitination
8.
Eukaryot Cell ; 7(9): 1530-9, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18606827

ABSTRACT

The Ras family of proteins is a large group of monomeric GTPases. Members of the fungal Ras family act as molecular switches that transduce signals from the outside of the cell to signaling cascades inside the cell. A. fumigatus RasA is 94% identical to the essential RasA gene of Aspergillus nidulans and is the Ras family member sharing the highest identity to Ras homologs studied in many other fungi. In this study, we report that rasA is not essential in A. fumigatus, but its absence is associated with slowed germination and a severe defect in radial growth. The DeltarasA hyphae were more than two times the diameter of wild-type hyphae, and they displayed repeated changes in the axis of polarity during hyphal growth. The deformed hyphae accumulated numerous nuclei within each hyphal compartment. The DeltarasA mutant conidiated poorly, but this phenotype could be ameliorated by growth on osmotically stabilized media. The DeltarasA mutant also showed increased susceptibility to cell wall stressors, stained more intensely with calcofluor white, and was refractory to lysing enzymes used to make protoplasts, suggesting an alteration of the cell wall. All phenotypes associated with deletion of rasA could be corrected by reinsertion of the wild-type gene. These data demonstrate a crucial role for RasA in both hyphal growth and asexual development in A. fumigatus and provide evidence that RasA function is linked to cell wall integrity.


Subject(s)
Aspergillus fumigatus/growth & development , Aspergillus fumigatus/metabolism , Cell Wall/metabolism , Fungal Proteins/metabolism , Gene Expression Regulation, Fungal , ras Proteins/metabolism , Aspergillus fumigatus/genetics , Cell Wall/genetics , Cyclic AMP/metabolism , Fungal Proteins/genetics , Hyphae/genetics , Hyphae/growth & development , Hyphae/metabolism , Sequence Deletion , Spores, Fungal/genetics , Spores, Fungal/growth & development , Spores, Fungal/metabolism , ras Proteins/genetics
9.
Article in English | MEDLINE | ID: mdl-17267253

ABSTRACT

We measured levels of select metabolites (glucose, triglycerides, free fatty acids, glycerol, uric acid) and corticosterone in the blood plasma of adult pied flycatchers Ficedula hypoleuca while they were rearing broods whose sizes were modified experimentally. We also made it more difficult than normal for some pairs of birds to forage by removing certain wing and tail feathers (handicapping them). Both procedures have been shown previously to change parental workload. We did this in order to determine if the birds alter their use of nutrients in response to differences in their workload. Metabolite levels were not influenced by handicapping or brood size. However, the concentration of free fatty acids in the plasma of females and of triglycerides in the plasma of males was directly related to the frequency with which the adults fed their nestlings. These findings suggest that the two sexes have different ways of coping with the work associated with rearing the brood: females apparently undergo brief daily fasts while feeding their chicks, whereas males take more time to feed themselves while providing food for their young, and spend more time doing so as their workload increases. The flycatchers exhibited high concentrations of uric acid and corticosterone in the blood plasma; corticosterone and glycerol were positively correlated in females; and corticosterone and triglyceride levels were negatively correlated in males; all of which suggest that gluconeogenesis provides some of the energy required for their parental activities.


Subject(s)
Nesting Behavior/physiology , Songbirds/blood , Animals , Breeding , Corticosterone/blood , Female , Glycerol/blood , Male , Time Factors
10.
Orthod Fr ; 77(2): 305-14, 2006 Jun.
Article in French | MEDLINE | ID: mdl-16866127

ABSTRACT

Faced to an abundant literature and to various clinical situations, practitioners are nowadays invited to implement an evidence based approach. This methodology, initially developed in Canada in the 80's, is getting widely used and is perfectly suited for Orthodontics and particularly for the evaluation of interceptive treatments. It is defined as the conscentious, explicit and judicious use of current best evidence in making decisions about the care of individual patients. This approach, which requires four different steps, will initially be presented. A methodological guide that allows to grade the evidence among different research protocols, will then be introduced. At the top of the hierarchy, randomized clinical trials have shown to be the best tools available to evaluate treatment efficiency. Different research designs are finally put forward to evaluate interceptive treatments.


Subject(s)
Evidence-Based Medicine , Orthodontics/methods , Databases, Bibliographic , Decision Making , Dental Research , Humans , Internet , Randomized Controlled Trials as Topic , Reproducibility of Results , Research Design , Terminology as Topic
11.
Orthod Fr ; 77(1): 101-3, 2006 Mar.
Article in French | MEDLINE | ID: mdl-16708658

ABSTRACT

The functional differences between breast-feeding and bottle-feeding may have a significant effect on dento-facial development and on the genesis of some severe malocclusions. Orthodontists should be aware of this sometimes under-estimated aspect of development. They should, in conformity with their role as professional health care providers, advise long-term breast feeding as a way of preventing certain disorders or, at least, reducing their severity.


Subject(s)
Bottle Feeding/adverse effects , Maxillofacial Development/physiology , Retrognathia/etiology , Retrognathia/prevention & control , Sucking Behavior/physiology , Humans , Infant , Mandible/physiopathology , Mouth Breathing/etiology , Mouth Breathing/prevention & control
12.
Poult Sci ; 84(2): 321-7, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15742970

ABSTRACT

A polycystic ovarian follicle (PCOF) syndrome associated with high baseline concentrations of progesterone (P4) without preovulatory luteinizing hormone (LH) surges has been reported in turkey hens. The PCOF syndrome could be induced in turkey hens by injecting P4 (0.33 mg/kg per d) daily early in the reproductive period for 10 to 12 d and then waiting 3 wk for the syndrome to develop. It was hypothesized that an arrest in laying associated with the PCOF syndrome could be induced by daily injection of P4 in restricted-fed broiler breeder hens. Hens were divided into 5 treatment groups and were injected subcutaneously daily with P4 in canola oil at dosages of 0, 0.17, 0.33, 0.5, and 1.5 mg/kg per d for 13 d, at 14 wk of egg production when they were 41 wk of age. Blood samples were collected on d 7 and 13 immediately before P4 injection. Oviductal and ovarian morphologies were measured at necropsy 1 d after the last P4 injection. Egg production rate was reduced by injection of P4 at dosages < 0.17 mg/kg per d. At dosages of 0.5 and 1.5 mg/kg per d, ovarian hierarchical follicles had regressed. None of the broiler breeder hens had the PCOF syndrome at necropsy, but a high incidence of hens holding hard-shelled uterine eggs for several days was observed. Concentrations of LH decreased with P4 injection at > 0.17 mg/kg per d, and P4 concentrations were increased with P4 injection at > 0.5 mg/kg per d. Estradiol-17beta (E2) concentrations were decreased at all P4 dosages. It was concluded that egg production rate was reduced by daily injection of P4 at dosages > 0.17 mg/kg per d, and egg production ceased and ovarian follicles and the oviduct regressed at dosages > 0.50 mg/kg per d. The PCOF syndrome, however, was not induced in restricted-fed broiler breeder hens by P4 injection.


Subject(s)
Oviposition/drug effects , Progesterone/toxicity , Animals , Chickens , Dose-Response Relationship, Drug , Estradiol/blood , Female , Luteinizing Hormone/blood , Ovarian Follicle/drug effects , Ovary/drug effects , Oviducts/drug effects , Progesterone/blood
13.
Poult Sci ; 83(12): 2051-8, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15615020

ABSTRACT

Young laying turkey hens ceased laying and developed a polycystic ovarian follicle (PCOF) syndrome 3 wk after injections of progesterone (P4) ceased. It was hypothesized that laying Japanese quail chronically injected with progesterone (P4) would respond with reduced or arrested egg production and altered ovarian morphology similar to that seen in turkeys expressing the PCOF syndrome, and could thus serve as a model to study the PCOF syndrome. To test these hypotheses, 6 trials were conducted with young photosensitive Japanese quail photostimulated to induce sexual maturity with either 24L:0D or 14L:10D at 6 or 8 wk of age, and used after 3 to 5 wk of egg production. The quail were injected once daily at dosages of 0, 0.17, 0.33, 0.5, 1.5, 3.0, or 4.5 mg of P4/kg per d, or twice daily at dosages of 0 and 1.5 mg of P4/kg for 8 to 14 d and were then necropsied 1 d after the last injection or after waiting an additional 8 to 14 d. During the injection period, egg production was not different among P4 dosages <1.5 mg of P4/kg per d, but decreased at dosages of 1.5 mg of P4/kg per d or greater. A decrease in egg production was found with twice daily injections of 1.5 mg of P4/kg. The decrease in egg production rate ceased and egg production resumed 5 to 7 d after the last injections of 3.0 and 4.5 mg of P4/kg per d or twice-daily injections of 1.5 mg of P4/kg. Compared with control hens, a high percentage of hens (from 12 to 75%) held a hard-shelled egg in the uterus during single daily injections at dosages of 3.0 and 4.5 mg of P4/kg per d and twice daily injections of 1.5 mg of P4/kg. Ovary and oviductal weights, and number of hierarchical follicles were not changed after chronic P4 injection, but more atretic follicles were found in hens at the end of 8 to 12 d of P4 injection. In conclusion, a decreasing egg production rate was induced by chronic P4 injection, but the decrease ceased and egg production resumed 5 to 7 d after the last injections in laying Japanese quail. Young quail hens, unlike young turkey hens, did not develop a PCOF-like syndrome after P4 injection.


Subject(s)
Coturnix/physiology , Oviposition/drug effects , Progesterone/toxicity , Animals , Body Weight/drug effects , Drug Administration Schedule/veterinary , Female , Light , Organ Size/drug effects , Ovarian Follicle/drug effects , Ovary/drug effects , Oviducts/drug effects , Poultry Diseases/chemically induced , Progesterone/administration & dosage , Turkeys
14.
Poult Sci ; 83(5): 815-22, 2004 May.
Article in English | MEDLINE | ID: mdl-15141841

ABSTRACT

A cannulation and serial bleeding procedure has been developed to monitor the peripheral patterns of hormones associated with reproduction for up to 10 d in broiler breeder hens. Hens were cannulated via the jugular vein and returned to individual cages. The unrestrained cannulated hens were connected to a tether and swivel system that permitted constant infusion for maintenance of the cannula prior to serial bleeding and unrestrained long-term serial bleeding for up to 10 d. In a short-term experiment hens were bled every 12 min for 36 h, and in a long-term experiment hens were bled hourly for 10 d. In these experiments, 1.5-mL blood samples were collected at each time point with sodium citrate as the anticoagulant. To avoid hemodilution, after removal of plasma the red blood cells were reconstituted with saline to the original volume and returned to the hen of origin. Collection of serial blood samples was successful from 94% of hens in the short-term experiment and 79% of hens in the long-term experiment. Egg production was not affected (P > 0.05) during the 6 wk following serial bleeding in the short-term experiment. For hens that continued laying, egg production for 10 d prior to cannulation was not different (P > 0.05) from egg production for the 10 d during serial bleeding in the long-term experiment. However, late in the reproductive cycle many hens (25%) stopped laying when serially bled. It is concluded that this cannulation procedure can be used to study short-term or long-term peripheral patterns of hormones associated with oviposition and ovulation in laying broiler breeder hens.


Subject(s)
Catheterization/veterinary , Chickens , Hormones/blood , Animals , Blood Specimen Collection/methods , Blood Specimen Collection/veterinary , Catheterization/adverse effects , Catheterization/methods , Female , Jugular Veins , Luteinizing Hormone/blood , Oviposition , Ovulation , Progesterone/blood
15.
Poult Sci ; 83(5): 823-9, 2004 May.
Article in English | MEDLINE | ID: mdl-15141842

ABSTRACT

Spontaneous ovulations are induced by preovulatory surges of luteinizing hormone (LH) and progesterone (P4) during ovulatory cycles in birds, but estradiol-17beta (E2) levels are relatively constant. Egg production is enhanced in restricted fed (RF) in comparison with ad libitum fed (FF) broiler breeder hens, but changes in concentrations and peripheral patterns of LH, P4, and E2 during ovulatory cycles in broiler breeder hens are poorly documented. The hypothesis of this study was that high resolution patterns of peripheral LH, P4, and E2 during preovulatory surges would not be different between FF and RF broiler breeder hens. Seven FF and 6 RF broiler breeder hens were photostimulated with 16 L:8 D at 22 wk of age. At 28 wk of age, the hens were cannulated for serial blood sampling and switched to a 24L:0D photoperiod to allow preovulatory surges of LH and P4 to run freely. Three days after cannulation, hens were serially bled every 12 min for 36 h. The FF hens were heavier than the RF hens (5.60 +/- 0.35 vs. 3.60 +/- 0.28 kg, respectively; P < 0.01). During the 10 d before cannulation, total egg production of the FF and RF hens (8.3 +/- 1.4 and 6.8 +/- 1.3 eggs, respectively; P = 0.08) and normal egg production (5.6 +/- 1.8 and 6.5 +/- 1.8 eggs, respectively; P = 0.37) were not different. The FF hens, however, had more abnormal eggs than the RF hens (2.7 +/- 1.7 and 0.3 +/- 0.8 eggs, respectively; P < 0.01). None of the hormonal measurements was different between the FF and RF hens (P > 0.05). The concentrations of hormones for the FF and RF hens, respectively, were as follows: baseline LH (2.79 +/- 0.45 vs. 2.94 +/- 0.60 ng/mL) and P4 (1.68 +/- 0.56 vs. 1.41 +/- 0.43 ng/mL), overall mean LH (3.18 +/- 0.45 vs. 3.10 +/- 0.46 ng/mL) and P4 (2.32 +/- 0.55 vs. 2.09 +/- 0.91 ng/ mL), preovulatory surge amplitude of LH (5.43 +/- 1.27 vs. 3.88 +/- 1.24 ng/mL) and P4 (6.08 +/- 2.09 vs. 6.71 +/- 3.91 ng/ mL), preovulatory surge duration of LH (7.52 +/- 1.80 vs. 5.74 +/- 3.18 h) and P4 (7.52 +/- 1.42 vs. 8.20 +/- 1.24 h), and overall mean E2 (0.25 +/- 0.05 vs. 0.23 +/- 0.05 ng/mL). In conclusion, there were no differences in total egg production or normal egg production between FF and RF broiler breeder hens, but the FF hens laid more abnormal eggs. Also, there were no differences in the concentrations or peripheral patterns of LH, P4, and E2 during preovulatory surges between the FF and RF broiler breeder hens.


Subject(s)
Chickens/physiology , Diet , Estradiol/blood , Luteinizing Hormone/blood , Ovulation/physiology , Progesterone/blood , Animals , Body Weight , Breeding , Female , Food Deprivation , Oviposition , Photoperiod
16.
Cancer Res ; 64(8): 2717-24, 2004 Apr 15.
Article in English | MEDLINE | ID: mdl-15087385

ABSTRACT

Neurofibromatosis type 2 (NF2) is a genetic disorder characterized by bilateral schwannomas of the eighth cranial nerve. The NF2 tumor suppressor protein, merlin, is related to the ERM (ezrin, radixin, and moesin) family of membrane/F-actin linkers. Merlin resists solubilization by the detergent Triton X-100 (TX-100), a property commonly attributed to association with the cytoskeleton. Accordingly, NF2 patient mutations that encode merlins with enhanced TX-100 solubility have been explained previously in terms of loss of cytoskeletal attachment. However, here we present data to suggest that the detergent resistance of merlin is a result of its constitutive residence in lipid rafts. Furthermore, when cells are grown to high density, merlin shifts to a more buoyant lipid raft fraction in a density gradient. This shift is mimicked in subconfluent cells treated with cytochalasin D, suggesting that the shift results from merlin dissociation from the actin cytoskeleton, but not from lipid rafts. Intramolecular NH(2)- and COOH-terminal binding, which occurs when merlin transitions to the growth-suppressive form, also brings about a similar change in buoyant density. Our results suggest that constitutive residence of merlin in lipid rafts is crucial for its function and that as merlin becomes growth suppressive in vivo, one significant molecular event may be the loss of interaction with the actin cytoskeleton. To our knowledge, merlin is the first tumor suppressor known to reside within lipid rafts, and the significance of this finding is underscored by known loss-of-function NF2 patient mutations that encode merlins with enhanced TX-100 solubility.


Subject(s)
Membrane Microdomains/metabolism , Neurofibromin 2/metabolism , Actins/metabolism , Animals , Caveolae/metabolism , Cell Line, Tumor , Detergents/pharmacology , Glioma/metabolism , Humans , Membrane Microdomains/drug effects , Mice , Microscopy, Confocal , NIH 3T3 Cells
18.
Poult Sci ; 82(12): 1985-9, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14717558

ABSTRACT

An arrest in egg laying associated with a polycystic ovarian follicle syndrome (PCOF) has been recently reported early in the egg production period in turkey hens photostimulated at 30 wk of age (WOA) with continuous light. When autopsied 2 to 3 wk after laying ceased, the ovaries of PCOF hens contained an increased number of mature size (F1) yolky follicles in comparison with normally laying hens plus several larger cystic follicles, while their oviducts were equal in weight to oviducts of hens laying normally. Four experiments were conducted to examine effects of age at photostimulation and photoperiod [14L:10D (14L) or continuous lighting 24L:0D (24L)] on the incidence of the PCOF syndrome. Turkey hens of the egg line were given short-day photostimulation of 6L:18D at 16 WOA and then photostimulated with either 14L or 24L at various ages between 26 to 70 WOA. Egg production was followed for 6 to 8 wk, and hens that stopped laying eggs during this period were autopsied 2 to 3 wk later to determine presence and incidence of the PCOF syndrome. At 26 WOA, the PCOF incidence was 80% with 24L lighting and 31% with 14L lighting (P = 0.006). At 28 WOA, the PCOF incidence was 56% with 24L lighting and 25% with 14L lighting (P = 0.072). At 31, 34, and 41 WOA, there were no differences (P > or = 0.10) in incidence of the PCOF syndrome between the 24L and 14L treatments. Within the 24L treatment, the PCOF incidence at 26 and 28 WOA (80 and 56%) were greater than at 31 WOA and older ages (< or = 20%; P < or = 0.025). Within the 14L lighting treatment, the PCOF incidence was not different among ages (26 WOA, 31% to 48 WOA, 0%; P > or = 0.05). It was concluded that the incidence of the PCOF syndrome is greater when photosensitive Egg line turkey hens are photostimulated at relatively young ages (less than 31WOA) and with 24L in comparison to 14L lighting.


Subject(s)
Aging , Light , Photoperiod , Polycystic Ovary Syndrome/veterinary , Poultry Diseases/etiology , Turkeys , Animals , Female , Oviposition , Polycystic Ovary Syndrome/epidemiology , Polycystic Ovary Syndrome/etiology , Poultry Diseases/epidemiology
19.
Poult Sci ; 81(7): 1057-64, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12162345

ABSTRACT

Turkey (Meleagridis gallopavo) liver cytosolic fatty acid binding protein (FABP) was purified and used as a standard for quantification. An immunoblotting procedure was developed to study the ontogeny of liver cytosolic FABP during embryonic and early posthatch development in turkey poults. Liver FABP activity was also determined indirectly through the use of gel filtration chromatography followed by a ligand-binding assay. The specific activity of liver FABP (ng/mg of cytosolic protein) increased with length of incubation, peaking initially at Day 22, declining between Days 22 and 25, and increasing again from hatch (Day 28) to 6 d posthatch. The specific activity of liver FABP increased 12-fold between Day 13 of incubation and 6 d posthatch compared with total activity, which increased from 946 to 1.01 x 10(6) ng/liver during the same period, a 1,067-fold increase. The results from both analytical procedures were similar, suggesting that the immunoblot method could be used to quantify liver FABP concentrations. The observed increases in FABP activity throughout the embryonic period and first days after hatching paralleled increases in liver lipid concentration. Therefore, liver FABP may be associated with hepatocyte fatty acid transport and metabolism during the latter stages of incubation and early posthatch period.


Subject(s)
Carrier Proteins/analysis , Immunoblotting/methods , Liver/chemistry , Neoplasm Proteins , Turkeys/embryology , Turkeys/growth & development , Animals , Body Weight , Carbon Radioisotopes , Chromatography, Gel , Cytosol/chemistry , Fatty Acid-Binding Proteins , Liver/embryology , Liver/growth & development , Oleic Acid/metabolism , Organ Size
20.
Poult Sci ; 81(2): 160-8, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11873824

ABSTRACT

Developmental stability of several Japanese quail lines was measured by bilateral asymmetry. Lines included in the study were as follows: a randombred control (R1), sublines of R1 selected for increased (HW line) and decreased (LW line) 4-wk BW, and sublines of R1 selected for increased (HP line) or decreased (LP line) total plasma phosphorus (TPP; a measure of yolk precursor in the blood) at the beginning of lay. In sublines of the HW line, the males were selected for increased 4-wk BW and the females for increased (HW-HP line) or decreased (HW-LP line) TPP. The HW, LW, HP, and LP lines were in their 41st generation of selection and the HW-HP and HW-LP lines in their 31st generation of selection. The number of birds in each line and sex subgroup was 30. The adult breeders (28 to 32 wk of age) were weighed and killed, and bilateral measurements were made of shank length, width (laterally at the dew claw), and depth (perpendicular to the dew claw), face length, and pectoralis major and p. minor weights. Data on asymmetry was expressed for the right side minus the left side as signed and absolute differences. In order to correct for the correlation between trait size and asymmetry, relative asymmetry (RA) was obtained by dividing the absolute differences between sides by the average value of both sides and multiplying by 100. All lines differed in BW at 4 wk of age with the ranking HW > HW-LP > HW-HP > LP > R1 > HP > LW. Line rankings of adult breeders were similar, except the HP and LP lines did not differ from the R1 line and the order of ranking of the HW-HP and HW-LP lines was opposite that at 4 wk of age. Line differences in signed and absolute differences were significant for most bilateral traits. However, after adjustment for trait size, line differences in RA were less frequent. In general, there were few significant differences in RA for the R1 line versus the selected lines, even though inbreeding of the R1 line (19%) was less than half that of the selected lines (44 to 57%), suggesting that homozygosity did not influence developmental stability. Selection for increased or decreased BW had little influence on RA. Developmental stability tended to be higher in the lines (LP and HW-LP) selected for decreased TPP. The data indicated that bilateral asymmetry was not a good measure of developmental stability in the current study.


Subject(s)
Body Weight/genetics , Coturnix/growth & development , Coturnix/genetics , Egg Yolk , Phosphorus/blood , Animals , Egg Proteins/blood , Female , Inbreeding , Male , Selection, Genetic
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