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1.
Plant Physiol ; 188(2): 1294-1311, 2022 02 04.
Article in English | MEDLINE | ID: mdl-34718759

ABSTRACT

Shade-intolerant plants rapidly elongate their stems, branches, and leaf stalks to compete with neighboring vegetation, maximizing sunlight capture for photosynthesis. This rapid growth adaptation, known as the shade-avoidance response (SAR), comes at a cost: reduced biomass, crop yield, and root growth. Significant progress has been made on the mechanistic understanding of hypocotyl elongation during SAR; however, the molecular interpretation of root growth repression is not well understood. Here, we explore the mechanisms by which SAR induced by low red:far-red light restricts primary and lateral root (LR) growth. By analyzing the whole-genome transcriptome, we identified a core set of shade-induced genes in roots of Arabidopsis (Arabidopsis thaliana) and tomato (Solanum lycopersicum) seedlings grown in the shade. Abiotic and biotic stressors also induce many of these shade-induced genes and are predominantly regulated by WRKY transcription factors. Correspondingly, a majority of WRKY genes were among the shade-induced genes. Functional analysis using transgenics of these shade-induced WRKYs revealed that their role is essentially to restrict primary root and LR growth in the shade; captivatingly, they did not affect hypocotyl elongation. Similarly, we also found that ethylene hormone signaling is necessary for limiting root growth in the shade. We propose that during SAR, shade-induced WRKY26, 45, and 75, and ethylene reprogram gene expression in the root to restrict its growth and development.


Subject(s)
Adaptation, Ocular/genetics , Arabidopsis/growth & development , Arabidopsis/genetics , Ethylenes/metabolism , Hypocotyl/growth & development , Hypocotyl/genetics , Plant Roots/growth & development , Plant Roots/genetics , Gene Expression Regulation, Plant , Genes, Plant , Genetic Variation , Genotype , Mutation , Transcription Factors
2.
Genet Med ; 24(6): 1227-1237, 2022 06.
Article in English | MEDLINE | ID: mdl-35300924

ABSTRACT

PURPOSE: This study aimed to describe the phenotypic and molecular characteristics of ARCN1-related syndrome. METHODS: Patients with ARCN1 variants were identified, and clinician researchers were connected using GeneMatcher and physician referrals. Clinical histories were collected from each patient. RESULTS: In total, we identified 14 cases of ARCN1-related syndrome, (9 pediatrics, and 5 fetal cases from 3 families). The clinical features these newly identified cases were compared to 6 previously reported cases for a total of 20 cases. Intrauterine growth restriction, micrognathia, and short stature were present in all patients. Other common features included prematurity (11/15, 73.3%), developmental delay (10/14, 71.4%), genitourinary malformations in males (6/8, 75%), and microcephaly (12/15, 80%). Novel features of ARCN1-related syndrome included transient liver dysfunction and specific glycosylation abnormalities during illness, giant cell hepatitis, hepatoblastoma, cataracts, and lethal skeletal manifestations. Developmental delay was seen in 73% of patients, but only 3 patients had intellectual disability, which is less common than previously reported. CONCLUSION: ARCN1-related syndrome presents with a wide clinical spectrum ranging from a severe embryonic lethal syndrome to a mild syndrome with intrauterine growth restriction, micrognathia, and short stature without intellectual disability. Patients with ARCN1-related syndrome should be monitored for liver dysfunction during illness, cataracts, and hepatoblastoma. Additional research to further define the phenotypic spectrum and possible genotype-phenotype correlations are required.


Subject(s)
Cataract , Dwarfism , Hepatoblastoma , Intellectual Disability , Liver Neoplasms , Micrognathism , Child , Female , Fetal Growth Retardation/genetics , Humans , Intellectual Disability/genetics , Male , Phenotype , Syndrome
3.
Clin Chem ; 65(5): 653-663, 2019 05.
Article in English | MEDLINE | ID: mdl-30770376

ABSTRACT

BACKGROUND: Congenital disorders of glycosylation (CDG) represent 1 of the largest groups of metabolic disorders with >130 subtypes identified to date. The majority of CDG subtypes are disorders of N-linked glycosylation, in which carbohydrate residues, namely, N-glycans, are posttranslationally linked to asparagine molecules in peptides. To improve the diagnostic capability for CDG, we developed and validated a plasma N-glycan assay using flow injection-electrospray ionization-quadrupole time-of-flight mass spectrometry. METHODS: After PNGase F digestion of plasma glycoproteins, N-glycans were linked to a quinolone using a transient amine group at the reducing end, isolated by a hydrophilic interaction chromatography column, and then identified by accurate mass and quantified using a stable isotope-labeled glycopeptide as the internal standard. RESULTS: This assay differed from other N-glycan profiling methods because it was free of any contamination from circulating free glycans and was semiquantitative. The low end of the detection range tested was at 63 nmol/L for disialo-biantennary N-glycan. The majority of N-glycans in normal plasma had <1% abundance. Abnormal N-glycan profiles from 19 patients with known diagnoses of 11 different CDG subtypes were generated, some of which had previously been reported to have normal N-linked protein glycosylation by carbohydrate-deficient transferrin analysis. CONCLUSIONS: The clinical specificity and sensitivity of N-glycan analysis was much improved with this method. Additional CDGs can be diagnosed that would be missed by carbohydrate-deficient transferrin analysis. The assay provides novel biomarkers with diagnostic and potentially therapeutic significance.


Subject(s)
Congenital Disorders of Glycosylation/diagnosis , Flow Injection Analysis/methods , Glycoproteins/blood , Polysaccharides/blood , Spectrometry, Mass, Electrospray Ionization/methods , Adolescent , Adult , Aged , Case-Control Studies , Child , Child, Preschool , Congenital Disorders of Glycosylation/blood , Glycoproteins/chemistry , Humans , Infant , Infant, Newborn , Middle Aged , Sensitivity and Specificity , Young Adult
4.
Am J Med Genet A ; 179(4): 542-551, 2019 04.
Article in English | MEDLINE | ID: mdl-30719864

ABSTRACT

Sotos syndrome is an overgrowth syndrome characterized by distinctive facial features and intellectual disability caused by haploinsufficiency of the NSD1 gene. Genotype-phenotype correlations have been observed, with major anomalies seen more frequently in patients with 5q35 deletions than those with point mutations in NSD1. Though endocrine features have rarely been described, transient hyperinsulinemic hypoglycemia (HI) of the neonatal period has been reported as an uncommon presentation of Sotos syndrome. Eight cases of 5q35 deletions and one patient with an intragenic NSD1 mutation with transient HI have been reported. Here, we describe seven individuals with HI caused by NSD1 gene mutations with three having persistent hyperinsulinemic hypoglycemia. These patients with persistent HI and Sotos syndrome caused by NSD1 mutations, further dispel the hypothesis that HI is due to the deletion of other genes in the deleted 5q35 region. These patients emphasize that NSD1 haploinsufficiency is sufficient to cause HI, and suggest that Sotos syndrome should be considered in patients presenting with neonatal HI. Lastly, these patients help extend the phenotypic spectrum of Sotos syndrome to include HI as a significant feature.


Subject(s)
Congenital Hyperinsulinism/pathology , Developmental Disabilities/pathology , Growth Disorders/pathology , Histone-Lysine N-Methyltransferase/genetics , Mutation , Sotos Syndrome/pathology , Adult , Congenital Hyperinsulinism/genetics , Developmental Disabilities/genetics , Female , Growth Disorders/genetics , Humans , Infant , Infant, Newborn , Male , Phenotype , Prognosis , Sotos Syndrome/genetics
5.
Genet Med ; 19(11): 1226-1235, 2017 11.
Article in English | MEDLINE | ID: mdl-28617415

ABSTRACT

PurposePhosphoglucomutase-1 deficiency is a subtype of congenital disorders of glycosylation (PGM1-CDG). Previous casereports in PGM1-CDG patients receiving oral D-galactose (D-gal) showed clinical improvement. So far no systematic in vitro and clinical studies have assessed safety and benefits of D-gal supplementation. In a prospective pilot study, we evaluated the effects of oral D-gal in nine patients.MethodsD-gal supplementation was increased to 1.5 g/kg/day (maximum 50 g/day) in three increments over 18 weeks. Laboratory studies were performed before and during treatment to monitor safety and effect on serum transferrin-glycosylation, coagulation, and liver and endocrine function. Additionally, the effect of D-gal on cellular glycosylation was characterized in vitro.ResultsEight patients were compliant with D-gal supplementation. No adverse effects were reported. Abnormal baseline results (alanine transaminase, aspartate transaminase, activated partial thromboplastin time) improved or normalized already using 1 g/kg/day D-gal. Antithrombin-III levels and transferrin-glycosylation showed significant improvement, and increase in galactosylation and whole glycan content. In vitro studies before treatment showed N-glycan hyposialylation, altered O-linked glycans, abnormal lipid-linked oligosaccharide profile, and abnormal nucleotide sugars in patient fibroblasts. Most cellular abnormalities improved or normalized following D-gal treatment. D-gal increased both UDP-Glc and UDP-Gal levels and improved lipid-linked oligosaccharide fractions in concert with improved glycosylation in PGM1-CDG.ConclusionOral D-gal supplementation is a safe and effective treatment for PGM1-CDG in this pilot study. Transferrin glycosylation and ATIII levels were useful trial end points. Larger, longer-duration trials are ongoing.


Subject(s)
Galactose/therapeutic use , Glycogen Storage Disease/drug therapy , Administration, Oral , Adolescent , Blood Coagulation , Blood Glucose/metabolism , Child , Child, Preschool , Creatine Kinase/blood , Dose-Response Relationship, Drug , Female , Galactose/administration & dosage , Galactose/adverse effects , Glycoproteins/metabolism , Humans , Infant , Male , Phosphoglucomutase/metabolism , Pilot Projects , Prospective Studies , Skin/cytology , Skin/metabolism , Transferrin/metabolism , Young Adult
6.
Am J Med Genet A ; 173(7): 1907-1912, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28436160

ABSTRACT

Heterozygous mutations in the genes encoding the proα1(I) or proα2(I) chains of type I procollagen (COL1A1 and COL1A2, respectively) account for most cases of osteogenesis imperfecta (OI), a disorder characterized by reduced bone strength and increased fracture risk. COL1A1 mutations can also cause rare cases of Ehlers-Danlos syndrome (EDS), a disorder that primarily affects connective tissue and often includes reduced bone mass. Here we present a kindred of three young siblings ages 1-4 years old whose mother has a history of mild type I OI. All three children are compound heterozygotes for COL1A1 mutations, with a novel frameshift mutation (c.2522delC; p.Pro841Leufs*266) from their mother and a known missense mutation (c.3196C>T; p.R1066C) from their clinically unaffected father, which has previously been described as causing a combined type I OI/EDS phenotype. The three children exhibit features of both COL1A1 mutations: early and frequent long bone fractures, joint hyperextensibility, and blue sclerae. We describe three siblings who are the first reported surviving subjects with biallelic pathogenic COL1A1 mutations. They have a more severe form of type I OI with features of EDS that represents their compound heterozygosity for two deleterious COL1A1 mutations. Their long-term outcomes are yet to be determined.

7.
Vet Dermatol ; 28(2): 195-e44, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27943548

ABSTRACT

BACKGROUND: Mycophenolate mofetil (MMF) is a lymphocytotoxic immunosuppressive agent used in human and companion animal medicine for the treatment of immune-mediated disease. Mycophenolate mofetil is reported to have reduced myelotoxicity and hepatotoxicity when compared to azathioprine. OBJECTIVES: It was hypothesized that treatment with MMF as a secondary agent with glucocorticoids would be effective in treating immune-mediated skin disease. In addition, adverse effects associated with the drug are reported. ANIMALS: Fourteen dogs from a hospital population diagnosed with immune-mediated skin disease. METHODS: A retrospective review of medical records from 2010 to 2015 was used to identify dogs with immune-mediated skin disease that were treated with MMF. RESULTS: All dogs were treated with MMF (mean dose 14.7 mg/kg twice daily) in conjunction with glucocorticoids. Ten of 14 cases showed positive results, with complete remission in eight cases and partial remission in two cases. Mean time to remission was 5.7 weeks. Therapy was discontinued in one case (perianal fistula) due to lack of response. Adverse events were noted in six cases and included diarrhoea (n = 6), haematochezia (n = 2), vomiting (n = 3) and papilloma formation (n = 1). Therapy was discontinued in two cases with diarrhoea. Mycophenolate mofetil was discontinued in an additional case because of a diagnosis of neoplasia. All other adverse events were self-limiting or easily medically managed. No hepatotoxicity or bone marrow suppression was noted. CONCLUSION: This study supports the use of MMF as a second-line immunotherapeutic in immune-mediated skin disease in dogs.


Subject(s)
Dog Diseases/drug therapy , Glucocorticoids/therapeutic use , Mycophenolic Acid/therapeutic use , Skin Diseases/veterinary , Animals , Dogs , Glucocorticoids/administration & dosage , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/therapeutic use , Mycophenolic Acid/administration & dosage , Mycophenolic Acid/adverse effects , Retrospective Studies , Skin Diseases/drug therapy , Skin Diseases/immunology
8.
Vet Dermatol ; 28(4): 417-e102, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28337800

ABSTRACT

BACKGROUND: Mycoplasma spp. are commensal organisms found in association with the mucus membranes of all mammalian species and are implicated in bacterial infections of many different locations. Mycoplasma spp. as a primary pathogen associated with otitis media in cats has not been reported. OBJECTIVES: To describe three cats with Mycoplasma infection of the middle ear associated with various underlying disease processes. ANIMALS: Three client-owned cats. METHODS: Clinical examination, aerobic culture of the middle ear and computed tomography or magnetic resonance imaging of the skull. RESULTS: Mycoplasma spp. were grown on aerobic culture from the middle ear of three cats. In Case 1, concurrent neoplasia of the bulla was identified. Mycoplasma alone was cultured in Case 2 and Mycoplasma was grown in addition to Bordetella in Case 3. Case 1 was euthanized, Case 2 responded to Mycoplasma targeted therapy and Case 3 responded to Bordetella targeted therapy. CONCLUSIONS AND CLINICAL IMPORTANCE: Mycoplasma infections of the middle ear may be clinically important and require targeted treatment in some cases.


Subject(s)
Cat Diseases/microbiology , Mycoplasma Infections/veterinary , Otitis Media/veterinary , Animals , Cat Diseases/diagnosis , Cat Diseases/pathology , Cats , Ear, Middle/microbiology , Male , Mycoplasma , Mycoplasma Infections/diagnosis , Mycoplasma Infections/microbiology , Mycoplasma Infections/pathology , Otitis Media/diagnosis , Otitis Media/microbiology , Otitis Media/pathology , Tomography, X-Ray Computed/veterinary
9.
J Pediatr ; 175: 130-136.e8, 2016 08.
Article in English | MEDLINE | ID: mdl-27206562

ABSTRACT

OBJECTIVE: To define phenotypic groups and identify predictors of disease severity in patients with phosphoglucomutase-1 deficiency (PGM1-CDG). STUDY DESIGN: We evaluated 27 patients with PGM1-CDG who were divided into 3 phenotypic groups, and group assignment was validated by a scoring system, the Tulane PGM1-CDG Rating Scale (TPCRS). This scale evaluates measurable clinical features of PGM1-CDG. We examined the relationship between genotype, enzyme activity, and TPCRS score by using regression analysis. Associations between the most common clinical features and disease severity were evaluated by principal component analysis. RESULTS: We found a statistically significant stratification of the TPCRS scores among the phenotypic groups (P < .001). Regression analysis showed that there is no significant correlation between genotype, enzyme activity, and TPCRS score. Principal component analysis identified 5 variables that contributed to 54% variance in the cohort and are predictive of disease severity: congenital malformation, cardiac involvement, endocrine deficiency, myopathy, and growth. CONCLUSIONS: We established a scoring algorithm to reliably evaluate disease severity in patients with PGM1-CDG on the basis of their clinical history and presentation. We also identified 5 clinical features that are predictors of disease severity; 2 of these features can be evaluated by physical examination, without the need for specific diagnostic testing and thus allow for rapid assessment and initiation of therapy.


Subject(s)
Glycogen Storage Disease/diagnosis , Phenotype , Severity of Illness Index , Adolescent , Adult , Algorithms , Child , Child, Preschool , Female , Genetic Markers , Genotype , Glycogen Storage Disease/enzymology , Glycogen Storage Disease/genetics , Humans , Male , Mutation , Phosphoglucomutase/deficiency , Phosphoglucomutase/genetics , Physical Examination , Principal Component Analysis , Regression Analysis , Young Adult
10.
Vet Dermatol ; 26(5): 391-2, e89, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26189440

ABSTRACT

This report describes a dog that developed erythema multiforme in temporal association with administration of the sulphonamide-based anticonvulsant drug zonisamide. Similar adverse drug reactions have been associated with sulphonamide antimicrobial drugs. Caution should be exercised when prescribing this medication for dogs with known hypersensitivity to sulphonamides.


Subject(s)
Anticonvulsants/adverse effects , Dog Diseases/chemically induced , Erythema Multiforme/veterinary , Isoxazoles/adverse effects , Animals , Dog Diseases/pathology , Dogs , Epilepsy/drug therapy , Epilepsy/veterinary , Erythema Multiforme/chemically induced , Erythema Multiforme/pathology , Male , Skin/pathology , Zonisamide
11.
bioRxiv ; 2023 Jan 17.
Article in English | MEDLINE | ID: mdl-36711495

ABSTRACT

N6-methyladenosine is a highly dynamic, abundant mRNA modification which is an excellent potential mechanism for fine tuning gene expression. Plants adapt to their surrounding light and temperature environment using complex gene regulatory networks. The role of m6A in controlling gene expression in response to variable environmental conditions has so far been unexplored. Here, we map the transcriptome-wide m6A landscape under various light and temperature environments. Identified m6A-modifications show a highly specific spatial distribution along transcripts with enrichment occurring in 5'UTR regions and around transcriptional end sites. We show that the position of m6A modifications on transcripts might influence cellular transcript localization and the presence of m6A-modifications is associated with alternative polyadenylation, a process which results in multiple RNA isoforms with varying 3'UTR lengths. RNA with m6A-modifications exhibit a higher preference for shorter 3'UTRs. These shorter 3'UTR regions might directly influence transcript abundance and localization by including or excluding cis-regulatory elements. We propose that environmental stimuli might change the m6A landscape of plants as one possible way of fine tuning gene regulation through alternative polyadenylation and transcript localization.

12.
J Clin Invest ; 133(11)2023 06 01.
Article in English | MEDLINE | ID: mdl-36976649

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy that harbors mutations in homologous recombination-repair (HR-repair) proteins in 20%-25% of cases. Defects in HR impart a specific vulnerability to poly ADP ribose polymerase inhibitors and platinum-containing chemotherapy in tumor cells. However, not all patients who receive these therapies respond, and many who initially respond ultimately develop resistance. Inactivation of the HR pathway is associated with the overexpression of polymerase theta (Polθ, or POLQ). This key enzyme regulates the microhomology-mediated end-joining (MMEJ) pathway of double-strand break (DSB) repair. Using human and murine HR-deficient PDAC models, we found that POLQ knockdown is synthetically lethal in combination with mutations in HR genes such as BRCA1 and BRCA2 and the DNA damage repair gene ATM. Further, POLQ knockdown enhances cytosolic micronuclei formation and activates signaling of cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING), leading to enhanced infiltration of activated CD8+ T cells in BRCA2-deficient PDAC tumors in vivo. Overall, POLQ, a key mediator in the MMEJ pathway, is critical for DSB repair in BRCA2-deficient PDAC. Its inhibition represents a synthetic lethal approach to blocking tumor growth while concurrently activating the cGAS-STING signaling pathway to enhance tumor immune infiltration, highlighting what we believe to be a new role for POLQ in the tumor immune environment.


Subject(s)
Adenocarcinoma , Pancreatic Neoplasms , Humans , Animals , Mice , Adenocarcinoma/drug therapy , Adenocarcinoma/genetics , DNA Breaks, Double-Stranded , Cell Line, Tumor , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/genetics , Nucleotidyltransferases/genetics , Nucleotidyltransferases/metabolism , Homologous Recombination , Signal Transduction , Immunity , Pancreatic Neoplasms
13.
Curr Biol ; 32(15): 3221-3231.e6, 2022 08 08.
Article in English | MEDLINE | ID: mdl-35700731

ABSTRACT

Light is a crucial exogenous signal sensed by cryptochrome (CRY) blue light receptors to modulate growth and the circadian clock in plants and animals. However, how CRYs interpret light quantity to regulate growth in plants remains poorly understood. Furthermore, CRY2 protein levels and activity are tightly regulated in light to fine-tune hypocotyl growth; however, details of the mechanisms that explain precise control of CRY2 levels are not fully understood. We show that in Arabidopsis, UBP12 and UBP13 deubiquitinases physically interact with CRY2 in light. UBP12/13 negatively regulates CRY2 by promoting its ubiquitination and turnover to modulate hypocotyl growth. Growth and development were explicitly affected in blue light when UBP12/13 were disrupted or overexpressed, indicating their role alongside CRY2. UBP12/13 also interacted with and stabilized COP1, which is partially required for CRY2 turnover. Our combined genetic and molecular data support a mechanistic model in which UBP12/13 interact with CRY2 and COP1, leading to the stabilization of COP1. Stabilized COP1 then promotes the ubiquitination and degradation of CRY2 under blue light. Despite decades of studies on deubiquitinases, the knowledge of how their activity is regulated is limited. Our study provides insight into how exogenous signals and ligands, along with their receptors, regulate deubiquitinase activity by protein-protein interaction. Collectively, our results provide a framework of cryptochromes and deubiquitinases to detect and interpret light signals to control plant growth at the most appropriate time.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/metabolism , Arabidopsis Proteins/metabolism , Cryptochromes/genetics , Cryptochromes/metabolism , Deubiquitinating Enzymes/genetics , Deubiquitinating Enzymes/metabolism , Endopeptidases , Gene Expression Regulation, Plant , Light
14.
Hum Gene Ther ; 33(15-16): 789-800, 2022 08.
Article in English | MEDLINE | ID: mdl-35297680

ABSTRACT

Diabetes mellitus, caused by loss or dysfunction of the insulin-producing beta cells of the pancreas, is a promising target for recombinant adeno-associated virus (rAAV)-mediated gene therapy. To target potential therapeutic payloads specifically to beta cells, a cell type-specific expression control element is needed. In this study, we tested a series of rAAV vectors designed to express transgenes specifically in human beta cells using the islet-tropic rAAV-KP1 capsid. A small promoter, consisting of only 84 bp of the insulin core promoter was not beta cell-specific in AAV, but highly active in multiple cell types, including tissues outside the pancreas. A larger 363 bp fragment of the insulin promoter (INS) also lacked beta cell specificity. However, beta cell-specific expression was achieved by combining two regulatory elements, a promoter consisting of two copies of INS (INS × 2) and microRNA (miRNA) recognition elements (MREs). The INS × 2 promoter alone showed some beta cell preference, but not tight specificity. To reduce unspecific transgene expression in alpha cells, negative regulation by miRNAs was applied. MREs that are recognized by miRNAs abundant in alpha cells effectively downregulated the transgene expression in these cells. The INS2 × -MRE expression vector was highly specific to human beta cells and stem cell-derived beta cells.


Subject(s)
Dependovirus , MicroRNAs , Dependovirus/genetics , Dependovirus/metabolism , Genetic Vectors/genetics , Humans , Insulin/metabolism , MicroRNAs/metabolism , Transgenes
15.
PLoS One ; 17(12): e0278632, 2022.
Article in English | MEDLINE | ID: mdl-36473007

ABSTRACT

Total knee arthroplasty (TKA) is the final treatment option for patients with advanced knee osteoarthritis (OA). Unfortunately, TKA surgery is accompanied by acute postoperative pain that is more severe than arthroplasty performed in other joints. Elucidating the molecular mechanisms specific to post-TKA pain necessitates an animal model that replicates clinical TKA procedures, induces acute postoperative pain, and leads to complete functional recovery. Here, we present a new preclinical TKA model in rats and report on functional and behavioral outcomes indicative of pain, analgesic efficacy, serum cytokine levels, and dorsal root ganglia (DRG) transcriptomes during the acute postoperative period. Following TKA, rats exhibited marked deficits in weight bearing that persisted for 28 days. Home cage locomotion, rearing, and gait were similarly impacted and recovered by day 14. Cytokine levels were elevated on postoperative days one and/or two. Treatment with morphine, ketorolac, or their combination improved weight bearing while gabapentin lacked efficacy. When TKA was performed in rats with OA, similar functional deficits and comparable recovery time courses were observed. Analysis of DRG transcriptomes revealed upregulation of transcripts linked to multiple molecular pathways including inflammation, MAPK signaling, and cytokine signaling and production. In summary, we developed a clinically relevant rat TKA model characterized by resolution of pain and functional recovery within five weeks and with pain-associated behavioral deficits that are partially alleviated by clinically administered analgesics, mirroring the postoperative experience of TKA patients.


Subject(s)
Arthroplasty, Replacement, Knee , Rats , Animals , Arthroplasty, Replacement, Knee/adverse effects , Ganglia, Spinal , Pain, Postoperative/drug therapy , Pain, Postoperative/genetics , Cytokines/genetics
16.
Front Pediatr ; 9: 699129, 2021.
Article in English | MEDLINE | ID: mdl-34336745

ABSTRACT

Focal hyperinsulinism (HI) comprises nearly 50% of all surgically treated HI cases and is cured if the focal lesion can be completely resected. Pre-operative localization of the lesion is thus critical. Few cases of hyperinsulinism with multiple focal lesions have been reported, and assessment of the molecular mechanisms driving this rare occurrence has been limited. We present two cases of multifocal HI, each resulting from two independent, pancreatic focal lesions. 18Fluoro-dihydroxyphenylalanine positron emission tomography/computed tomography detected both lesions preoperatively in one patient, whereas identification of the second lesion was an incidental finding during surgical exploration in the other. Complete resection of the focal lesions resulted in cure of the HI in both cases. In each patient, genetic testing of the individual focal lesions revealed different regions of loss of heterozygosity for the maternal 11p15 allele, confirming that each lesion arose from independent somatic events in the setting of a paternally inherited germline ABCC8 mutation. These cases highlight the importance of a multidisciplinary and personalized approach to the management of infants with HI.

17.
J Endocr Soc ; 5(2): bvaa196, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-33490854

ABSTRACT

Aminoacyl-tRNA synthetases (ARSs) are crucial enzymes for protein translation. Mutations in genes encoding ARSs are associated with human disease. Tyrosyl-tRNA synthetase is encoded by YARS which is ubiquitously expressed and implicated in an autosomal dominant form of Charcot-Marie-Tooth and autosomal recessive YARS-related multisystem disease. We report on a former 34-week gestational age male who presented at 2 months of age with failure to thrive (FTT) and cholestatic hepatitis. He was subsequently diagnosed with hyperinsulinemic hypoglycemia with a negative congenital hyperinsulinism gene panel and F-DOPA positron-emission tomography (PET) scan that did not demonstrate a focal lesion. Autopsy findings were notable for overall normal pancreatic islet size and morphology. Trio whole exome sequencing identified a novel homozygous variant of uncertain significance in YARS (c.611A > C, p.Tyr204Cys) with each parent a carrier for the YARS variant. Euglycemia was maintained with diazoxide (max dose, 18 mg/kg/day), and enteral dextrose via gastrostomy tube (G-Tube). During his prolonged hospitalization, the patient developed progressive liver disease, exocrine pancreatic insufficiency, acute renal failure, recurrent infections, ichthyosis, hematologic concerns, hypotonia, and global developmental delay. Such multisystem features have been previously reported in association with pathogenic YARS mutations. Although hypoglycemia has been associated with pathogenic YARS mutations, this report provides more conclusive data that a YARS variant can cause hyperinsulinemic hypoglycemia. This case expands the allelic and clinical heterogeneity of YARS-related disease. In addition, YARS-related disease should be considered in the differential of hyperinsulinemic hypoglycemia associated with multisystem disease.

18.
Cell Metab ; 28(5): 787-792.e3, 2018 11 06.
Article in English | MEDLINE | ID: mdl-30057067

ABSTRACT

Recent reports identified activation of the GABA signaling pathway as a means to induce transdifferentiation of pancreatic α cells into ß cells. These reports followed several previous studies that found that α cells were particularly well suited to conversion into ß cells in mice, but only after nearly complete ß cell loss or forced overexpression of key transcriptional regulators. The possibility of increasing ß cell number via reprograming of α cells with a small molecule is enticing, as this could be a potential new pharmacologic therapy for diabetes. Here, we employed rigorous genetic lineage tracing of α cells, using Glucagon-CreERT2;Rosa-LSL-eYFP mice, to evaluate if activation of GABA signaling caused α-to-ß cell reprogramming. In contrast to previous reports, we found that even after long-term treatment of mice with artesunate or GABA, neither α-to-ß cell transdifferentiation nor insulin secretion were stimulated, putting into question whether these agents represent a viable path to a novel diabetes therapy.


Subject(s)
Artesunate/pharmacology , Cell Transdifferentiation/drug effects , Glucagon-Secreting Cells/drug effects , Insulin-Secreting Cells/drug effects , Insulin/metabolism , gamma-Aminobutyric Acid/pharmacology , Animals , Artesunate/administration & dosage , Glucagon-Secreting Cells/cytology , Glucagon-Secreting Cells/metabolism , Glucose Tolerance Test , Insulin-Secreting Cells/cytology , Insulin-Secreting Cells/metabolism , Male , Mice , Mice, Inbred C57BL , Signal Transduction/drug effects , gamma-Aminobutyric Acid/administration & dosage
19.
J Pain Res ; 11: 473-482, 2018.
Article in English | MEDLINE | ID: mdl-29551907

ABSTRACT

BACKGROUND: Metabolism of the endocannabinoid 2-arachidonoylglycerol (2-AG) yields arachidonic acid (AA), the precursor to proalgesic eicosanoids including prostaglandin E2 (PGE2). Diacylglycerol lipase ß (DAGLß) is an enzyme that synthesizes 2-AG and its inhibition reduces eicosanoid levels and produces antinociceptive effects in models of inflammatory pain. Here we test whether inhibition of DAGLß produces antinociceptive effects in a model of postoperative pain. METHODS: Rats were administered the selective DAGLß inhibitor KT109 or vehicle and underwent plantar incision. Postsurgical pain/disability was examined using evoked (mechanical hyperalgesia), functional (incapacitance/weight bearing), and functional/spontaneous (locomotion) modalities. RESULTS: Activity-based protein profiling confirmed that KT109 inhibited DAGLß in the lumbar spinal cord (LSC) and brain, confirming that it is a systemically active DAGLß inhibitor. Treatment with KT109 reduced basal 2-AG, AA, and PGE2 levels in the liver but not the brain, indicating that DAGLß activity does not significantly contribute to basal PGE2 production within the central nervous system. Plantar incision elevated the levels of 2-AG and PGE2 in the LSC. Although KT109 did not alter postsurgical 2-AG levels in the LSC, it slightly reduced PGE2 levels. In contrast, the clinically efficacious cyclooxygenase inhibitor ketoprofen completely suppressed PGE2 levels in the LSC. Similarly, KT109 had no significant effect upon postsurgical 2-AG, AA, or PGE2 levels at the incision site, while ketoprofen abolished PGE2 production at this location. KT109 and ketoprofen reversed the weight bearing imbalance induced by plantar incision, yet neither KT109 nor ketoprofen had any significant effect on mechanical hyperalgesia. Treatment with ketoprofen partially but significantly rescued the locomotor deficit induced by incision while KT109 was without effect. CONCLUSION: DAGLß is not the principal enzyme that controls 2-AG derived AA and PGE2 production after surgery, and inhibitors targeting this enzyme are unlikely to be efficacious analgesics superior to those already approved to treat acute postoperative pain.

20.
J Mol Endocrinol ; 38(1-2): 193-206, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17293440

ABSTRACT

Pancreatic beta-cells are responsible for producing all of the insulin required by an organism to maintain glucose homeostasis. Defects in development, maintenance, or expansion of beta-cell mass can result in impaired glucose metabolism and diabetes. Thus, identifying the molecular regulators of these processes may provide new therapeutic targets for diabetes. Additionally, understanding the processes of beta-cell differentiation and proliferation may allow for in vitro cultivation of beta-cells in sufficient amounts to be transplanted into patients with diabetes. This review addresses many of the transcription factors and signaling pathways that play a role in early pancreatic development and endocrine cell (specifically beta-cell) differentiation, conditions that influence beta-cell mass development and molecular regulators of beta-cell proliferation and apoptosis that are responsible for maintaining and expanding beta-cell mass.


Subject(s)
Cell Differentiation/physiology , Cell Proliferation , Insulin-Secreting Cells/metabolism , Pancreas/growth & development , Animals , Humans , Insulin-Secreting Cells/cytology
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