ABSTRACT
ERI1 is a 3'-to-5' exoribonuclease involved in RNA metabolic pathways including 5.8S rRNA processing and turnover of histone mRNAs. Its biological and medical significance remain unclear. Here, we uncover a phenotypic dichotomy associated with bi-allelic ERI1 variants by reporting eight affected individuals from seven unrelated families. A severe spondyloepimetaphyseal dysplasia (SEMD) was identified in five affected individuals with missense variants but not in those with bi-allelic null variants, who showed mild intellectual disability and digital anomalies. The ERI1 missense variants cause a loss of the exoribonuclease activity, leading to defective trimming of the 5.8S rRNA 3' end and a decreased degradation of replication-dependent histone mRNAs. Affected-individual-derived induced pluripotent stem cells (iPSCs) showed impaired in vitro chondrogenesis with downregulation of genes regulating skeletal patterning. Our study establishes an entity previously unreported in OMIM and provides a model showing a more severe effect of missense alleles than null alleles within recessive genotypes, suggesting a key role of ERI1-mediated RNA metabolism in human skeletal patterning and chondrogenesis.
Subject(s)
Exoribonucleases , Histones , Humans , Exoribonucleases/genetics , Histones/genetics , Mutation, Missense/genetics , RNA, Ribosomal, 5.8S , RNA , RNA, Messenger/geneticsABSTRACT
As a multifunctional hormone-like molecule, melatonin exhibits a pleiotropic role in plant salt stress tolerance. While actin cytoskeleton is essential to plant tolerance to salt stress, it is unclear if and how actin cytoskeleton participates in the melatonin-mediated alleviation of plant salt stress. Here, we report that melatonin alleviates salt stress damage in pigeon pea by activating a kinase-like protein, which interacts with an actin-depolymerizing factor. Cajanus cajan Actin-Depolymerizing Factor 9 (CcADF9) has the function of severing actin filaments and is highly expressed under salt stress. The CcADF9 overexpression lines (CcADF9-OE) showed a reduction of transgenic root length and an increased sensitivity to salt stress. By using CcADF9 as a bait to screen an Y2H library, we identified actin depolymerizing factor-related phosphokinase 1 (ARP1), a novel protein kinase that interacts with CcADF9. CcARP1, induced by melatonin, promotes salt resistance of pigeon pea through phosphorylating CcADF9, inhibiting its severing activity. The CcARP1 overexpression lines (CcARP1-OE) displayed an increased transgenic root length and resistance to salt stress, whereas CcARP1 RNA interference lines (CcARP1-RNAi) presented the opposite phenotype. Altogether, our findings reveal that melatonin-induced CcARP1 maintains F-actin dynamics balance by phosphorylating CcADF9, thereby promoting root growth and enhancing salt tolerance.
Subject(s)
Cajanus , Melatonin , Melatonin/pharmacology , Melatonin/metabolism , Actins/metabolism , Cajanus/genetics , Destrin/metabolism , Salt Tolerance/genetics , Phosphorylation , Actin Cytoskeleton/metabolismABSTRACT
Aluminium (Al) toxicity decreases crop production in acid soils in general, but many crops have evolved complex mechanisms to resist it. However, our current understanding of how plants cope with Al stress and perform Al resistance is still at the initial stage. In this study, the citrate transporter CcMATE35 was identified to be involved in Al stress response. The release of citrate was increased substantially in CcMATE35 over-expression (OE) lines under Al stress, indicating enhanced Al resistance. It was demonstrated that transcription factor CcNFYB3 regulated the expression of CcMATE35, promoting the release of citrate from roots to increase Al resistance in pigeon pea. We also found that a Long noncoding RNA Targeting Citrate Synthase (CcLTCS) is involved in Al resistance in pigeon pea. Compared with controls, overexpression of CcLTCS elevated the expression level of the Citrate Synthase gene (CcCS), leading to increases in root citrate level and citrate release, which forms another module to regulate Al resistance in pigeon pea. Simultaneous overexpression of CcNFYB3 and CcLTCS further increased Al resistance. Taken together, these findings suggest that the two modules, CcNFYB3-CcMATE35 and CcLTCS-CcCS, jointly regulate the efflux and synthesis of citrate and may play an important role in enhancing the resistance of pigeon pea under Al stress.
Subject(s)
Cajanus , RNA, Long Noncoding , Citric Acid/metabolism , Cajanus/genetics , Aluminum/toxicity , Aluminum/metabolism , Citrate (si)-Synthase , Citrates/metabolismABSTRACT
Camurati-Engelmann disease (CED) is an autosomal dominant bone dysplasia characterized by progressive hyperostosis of the skull base and diaphyses of the long bones. CED is further divided into two subtypes, CED1 and CED2, according to the presence or absence of TGFB1 mutations, respectively. In this study, we used exome sequencing to investigate the genetic cause of CED2 in three pedigrees and identified two de novo heterozygous mutations in TGFB2 among the three patients. Both mutations were located in the region of the gene encoding the straitjacket subdomain of the latency-associated peptide (LAP) of pro-TGF-ß2. Structural simulations of the mutant LAPs suggested that the mutations could cause significant conformational changes and lead to a reduction in TGF-ß2 inactivation. An activity assay confirmed a significant increase in TGF-ß2/SMAD signaling. In vitro osteogenic differentiation experiment using iPS cells from one of the CED2 patients showed significantly enhanced ossification, suggesting that the pathogenic mechanism of CED2 is increased activation of TGF-ß2 by loss-of-function of the LAP. These results, in combination with the difference in hyperostosis patterns between CED1 and CED2, suggest distinct functions between TGFB1 and TGFB2 in human skeletal development and homeostasis.
ABSTRACT
Craniofacial microsomia (CFM), also known as the oculo-auriculo-vertebral spectrum, is a congenital disorder characterized by hypoplasia of the mandible and external ear due to tissue malformations originating from the first and second branchial arches. However, distinguishing it from other syndromes of branchial arch abnormalities is difficult, and causal variants remain unidentified in many cases. In this report, we performed an exome sequencing analysis of a Brazilian family with CFM. The proband was a 12-month-old boy with clinical findings consistent with the diagnostic criteria for CFM, including unilateral mandibular hypoplasia, microtia, and external auditory canal abnormalities. A heterozygous de novo nonsense variant (c.713C>G, p.S238*) in PUF60 was identified, which was predicted to be pathogenic in silico. PUF60 has been reported as a causal gene in Verheij syndrome, but not in CFM. Although the boy showed craniofacial abnormalities and developmental delay that overlapped with Verheij syndrome, the facial asymmetry with unilateral hypoplasia of the mandible observed in this case did not match the previously reported phenotypes of PUF60 variants. Our findings expand the phenotypic range of PUF60 variants that cover CFM and Verheij syndrome.
Subject(s)
Goldenhar Syndrome , Phenotype , Humans , Male , Goldenhar Syndrome/genetics , Goldenhar Syndrome/pathology , Goldenhar Syndrome/diagnosis , Infant , RNA Splicing Factors/genetics , Repressor Proteins/genetics , Exome Sequencing , Mandible/abnormalities , Mandible/pathology , Pedigree , Codon, Nonsense/geneticsABSTRACT
Endothelial dysfunction, a central hallmark of cardiovascular pathogenesis in diabetes mellitus, is characterized by impaired endothelial nitric oxide synthase (eNOS) and NO bioavailability. However, the underlying mechanisms remain unclear. Here in this study, we aimed to identify the role of calmodulin (CaM) in diabetic eNOS dysfunction. Human umbilical vein endothelial cells and murine endothelial progenitor cells (EPCs) treated with high glucose (HG) exhibited downregulated CaM mRNA/protein and vascular endothelial growth factor (VEGF) expression with impeded eNOS phosphorylation and cell migration/tube formation. These perturbations were reduplicated in CALM1-knockdown cells but prevented in CALM1-overexpressing cells. EPCs from type 2 diabetes animals behaved similarly to HG-treated normal EPCs, which could be rescued by CALM1-gene transduction. Consistently, diabetic animals displayed impaired eNOS phosphorylation, endothelium-dependent dilation, and CaM expression in the aorta, as well as deficient physical interaction of CaM and eNOS in the gastrocnemius. Local CALM1 gene delivery into a diabetic mouse ischemic hindlimb improved the blunted limb blood perfusion and gastrocnemius angiogenesis, and foot injuries. Diabetic patients showed insufficient foot microvascular autoregulation, eNOS phosphorylation, and NO production with downregulated CaM expression in the arterial endothelium, and abnormal CALM1 transcription in genome-wide sequencing analysis. Therefore, our findings demonstrated that downregulated CaM expression is responsible for endothelium dysfunction and angiogenesis impairment in diabetes, and provided a novel mechanism and target to protect against diabetic endothelial injury.
Subject(s)
Diabetes Mellitus, Type 2 , Humans , Mice , Animals , Diabetes Mellitus, Type 2/metabolism , Calmodulin/genetics , Calmodulin/metabolism , Vascular Endothelial Growth Factor A/metabolism , Human Umbilical Vein Endothelial Cells/metabolism , Endothelium/metabolism , Ischemia/metabolism , Nitric Oxide Synthase Type III/genetics , Nitric Oxide Synthase Type III/metabolism , Neovascularization, PhysiologicABSTRACT
Four new xanthone glucosides, 3-hydroxy-2-methoxyxanthone-4-O-ß-D-glucopyranoside (1), 4,8-dihydroxy-2-methoxyxanthone-3-O-ß-D-glucopyranoside (2), 2-methoxyxanthone-5-O-ß-D-glucopyranoside (3), 4-hydroxy-2-methoxyxanthone-3-O-ß-D-glucopyranoside (4), a new phenolic acid, 4,4'-dihydroxy-3,3'-imino-di-benzoic acid monomethyl ester (5), and a new isoquinoline, methyl 6-hydroxy-1-oxo-1,2,3,4-tetrahydroisoquinoline-4-carboxylate (6) were isolated from the fruit of Hypericum patulum. The structural elucidation of the isolated compounds was primarily based on HR-ESI-MS, UV, IR, 1D and 2D NMR. All compounds were evaluated for their inhibitory effect against LPS-induced NO production in RAW 264.7 cells. Compoundâ 2, 3 exhibited moderate inhibitory activity against NO production.
Subject(s)
Hypericum , Hypericum/chemistry , Fruit/chemistry , Glucosides/chemistry , Magnetic Resonance SpectroscopyABSTRACT
Cx43 is the major connexin in ventricular gap junctions, and plays a pivotal role in control of electrical and metabolic communication among adjacent cardiomyocytes. We previously found that Cx43 dephosphorylation at serine 282 (pS282) caused cardiomyocyte apoptosis, which is involved in cardiac ischemia/reperfusion injury. In this study we investigated whether Cx43-S282 hyper-phosphorylation could protect cardiomyocytes against apoptosis. Adenovirus carrying rat full length Cx43 gene (Cx43-wt) or a mutant gene at S282 substituted with aspartic acid (S282D) were transfected into neonatal rat ventricular myocytes (NRVMs) or injected into rat ventricular wall. Rat abdominal aorta constriction model (AAC) was used to assess Cx43-S282 phosphorylation status. We showed that Cx43 phosphorylation at S282 was increased over 2-times compared to Cx43-wt cells at 24 h after transfection, while pS262 and pS368 were unaltered. S282D-transfected cells displayed enhanced gap junctional communication, and increased basal intracellular Ca2+ concentration and spontaneous Ca2+ transients compared to Cx43-wt cells. However, spontaneous apoptosis appeared in NRVMs transfected with S282D for 34 h. Rat ventricular myocardium transfected with S282D in vivo also exhibited apoptotic responses, including increased Bax/Bcl-xL ratio, cytochrome c release as well as caspase-3 and caspase-9 activities, while factor-associated suicide (Fas)/Fas-associated death domain expression and caspase-8 activity remained unaltered. In addition, AAC-induced hypertrophic ventricles had apoptotic injury with Cx43-S282 hyper-phosphorylation compared with Sham ventricles. In conclusion, Cx43 hyper-phosphorylation at S282, as dephosphorylation, also triggers cardiomyocyte apoptosis, but through activation of mitochondrial apoptosis pathway, providing a fine-tuned Cx43-S282 phosphorylation range required for the maintenance of cardiomyocyte function and survival.
Subject(s)
Apoptosis , Connexin 43 , Myocytes, Cardiac , Animals , Connexin 43/genetics , Connexin 43/metabolism , Mitochondria , Myocytes, Cardiac/metabolism , Phosphorylation , Rats , Serine/metabolismABSTRACT
BACKGROUND: The objective was to develop and validate an individualized nomogram to predict severe functional tricuspid regurgitation (S-FTR) after mitral valve replacement (MVR) via retrospective analysis of rheumatic heart disease (RHD) patients' pre-clinical characteristics. METHODS: Between 2001-2015, 442 MVR patients of RHD were examined. Transthoracic echocardiography detected S-FTR, and logistic regression model analyzed its independent predictors. R software established a nomogram prediction model, and Bootstrap determined its theoretical probability, which subsequently was compared with the actual patient probability to calculate the area under the curve (AUC) and calibration plots. Decision curve analysis (DCA) identified its clinical utility. RESULTS: Ninety-six patients developed S-FTR during the follow-up period. Both uni- and multivariate analyses found significant correlations between S-FTR occurrence with gender, age, atrial fibrillation (AF), pulmonary arterial hypertension (PH), left atrial diameter (LAD), and tricuspid regurgitation area (TRA). The individualized nomogram model had the AUC of 0.99 in internal verification. Calibration test indicated high agreement of predicted and actual S-FTR onset. DCA also showed that utilization of those six aforementioned factors was clinically useful. CONCLUSION: The nomogram for the patient characteristics of age, gender, AF, PH, LAD, and TRA found that they were highly predictive for future S-FTR onset within 5 years. This predictive ability therefore allows clinicians to optimize postoperative patient care and avoid unnecessary tricuspid valve surgeries.
Subject(s)
Mitral Valve Insufficiency , Tricuspid Valve Insufficiency , Child, Preschool , Heart Atria , Humans , Mitral Valve/diagnostic imaging , Mitral Valve/surgery , Mitral Valve Insufficiency/surgery , Retrospective Studies , Tricuspid Valve Insufficiency/diagnosis , Tricuspid Valve Insufficiency/etiology , Tricuspid Valve Insufficiency/surgeryABSTRACT
BACKGROUND: The aim of this study was to compare one-month acquisition and half-a-year quality retention of cardiopulmonary resuscitation (CPR) skills after initial training of medical students between peer videorecording feedback training (PVF) and traditional peer verbal feedback training (TVF). METHODS: Participants were randomly assigned to the PVF group (n = 62) and the TVF group (n = 65). All participants received a 45-min CPR training program performed by an American Heart Association basic life support-certified instructor, and then they began two hours of practice in groups. During interactive peer learning, students cooperated in couples of a doer and a helper to realize maximization of each other's learning. In the PVF group, training performance feedback came from peers based on practice videorecording. In the TVF group, feedback came from peers verbally without videorecording. CPR quality was tested at 1 and 6 months after training. RESULTS: After 1 month of initial training, the PVF group had a better presentation of CPR skills acquisition than the TVF group. Compared to the TVF group, the PVF group had significantly higher total scores, compression depth, appropriate compression depth, and complete chest recoil (p < 0.05). Moreover, compression interruption was a significantly positive change in the PVF group compared to the TVF group (p < 0.05). However, after 6 months, proportions of appropriate compression depth in the PVF group were better than those in the TVF group (p < 0.05). The differences in total scores, compression depth, appropriate compression depth, complete chest recoil and compression interruption were non-significant (all p > 0.05). CONCLUSIONS: Compared to TVF, PVF is more effective in enhancing CPR skill acquisition at 1 month. After half a year, CPR skill quality was obviously reduced in both groups, and no difference in CPR quality was found between the two groups.
Subject(s)
Cardiopulmonary Resuscitation , Students, Medical , Cardiopulmonary Resuscitation/education , Feedback , Humans , Manikins , Video RecordingABSTRACT
Dysosteosclerosis (DOS) is a distinct form of sclerosing bone disease characterized by platyspondyly and progressive osteosclerosis. DOS is genetically heterogeneous. Three causal genes, SLC29A3, CSF1R, and TNFRSF11A are reported. TNFRSF11A-associated DOS has been identified in two patients; however, TNFRSF11A is also a causal gene for osteopetrosis, autosomal recessive 7 (OP-AR7). Whole-exome sequencing in a patient with sclerosing bone disease identified novel compound heterozygous variants (c.414_427 + 7del, c.1664del) in TNFRSF11A. We examined the impact of the two variants on five splicing isoforms of TNFRSF11A by RT-PCR. We found that c.1664del resulted in elongated proteins (p.S555Cfs*121, etc.), while c.414_427 + 7del generated two aberrant splicing products (p.A139Wfs*19 and p.E132Dfs*19) that lead to nonsense mediated mRNA decay (NMD). In the previous two cases of TNFRSF11A-associated DOS, their mutations produced truncated TNFRSF11A protein isoforms. The mutations in all three cases thus contrast with TNFRSF11A mutations reported in OP-AR7, which does not generated truncated or elongated TNFRSF11A proteins. Thus, we identified the third case of TNFRSF11A-associated DOS and reinforced the genotype-phenotype correlation that aberrant protein-producing TNFRSF11A mutations cause DOS.
Subject(s)
Mutation , Osteosclerosis/pathology , Receptor Activator of Nuclear Factor-kappa B/genetics , Receptor Activator of Nuclear Factor-kappa B/metabolism , Child, Preschool , Female , Humans , Osteosclerosis/genetics , Osteosclerosis/metabolism , Prognosis , Exome SequencingABSTRACT
Dysosteosclerosis (DOS) is a rare sclerosing bone dysplasia characterized by osteosclerosis and platyspondyly. DOS is genetically heterogeneous and causally associated with mutations in three genes, SLC29A3, CSF1R, and TNFRSF11A. TNFRSF11A has been known as the causal gene for osteopetrosis, autosomal recessive 7, and is recently reported to cause DOS in three cases, which show a complex genotype-phenotype relationship. The phenotypic spectrum of TNFRSF11A-associated sclerosing bone dysplasia remains unclear and needs to be characterized further in more cases with molecular genetic diagnosis. Here, we report another TNFRSF11A-associated DOS case with a homozygous missense mutation (p.R129C). The mutation effect is different from the previous three cases, in which truncated or elongated RANK proteins were generated in isoform specific manner, thus enriching our understanding of the genotype-phenotype association in TNFRSF11A-associated sclerosing bone dysplasia. Besides DOS, our case presented with intracranial extramedullary hematopoiesis, which is an extremely rare condition and has not been identified in any other sclerosing bone dysplasias with molecular genetic diagnosis. Our findings provide the fourth case of TNFRSF11A-associated DOS and further expand its phenotypic spectrum.
Subject(s)
Hematopoiesis/genetics , Osteosclerosis/genetics , Receptor Activator of Nuclear Factor-kappa B/genetics , Bone Diseases , Child , Child, Preschool , Female , Genetic Association Studies , Genetic Heterogeneity , Homozygote , Humans , Infant , Intellectual Disability , Mutation/genetics , Nucleoside Transport Proteins/genetics , Osteopetrosis/genetics , Osteopetrosis/pathology , Osteosclerosis/diagnosis , Osteosclerosis/pathology , Phenotype , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/genetics , SclerosisABSTRACT
The RANKL/OPG/RANK signalling pathway is a major regulatory system for osteoclast formation and activity. Mutations in TNFSF11, TNFRSF11B and TNFRSF11A cause defects in bone metabolism and development, thereby leading to skeletal disorders with changes in bone density and/or morphology. To date, nine kinds of monogenic skeletal diseases have been found to be causally associated with TNFSF11, TNFRSF11B and TNFRSF11A mutations. These diseases can be divided into two types according to the mutation effects and the resultant pathogenesis. One is caused by the mutations inducing constitutional RANK activation or OPG deficiency, which increase osteoclastogenesis and accelerate bone turnover, resulting in juvenile Paget's disease 2, Paget disease of bone 2, familial expansile osteolysis, expansile skeletal hyperphosphatasia, panostotic expansile bone disease, and Paget disease of bone 5. The other is caused by the de-activating mutations in TNFRSF11A or TNFSF11, which decrease osteoclastogenesis and elevate bone density, resulting in osteopetrosis, autosomal recessive 2 and 7, and dysosteosclerosis. Here we reviewed the current knowledge about these genetic disorders with paying particular attention to the updating genotype-phenotype association in the TNFRSF11A-caused diseases.
Subject(s)
Genetic Diseases, Inborn/metabolism , Osteoprotegerin/metabolism , RANK Ligand/metabolism , Receptor Activator of Nuclear Factor-kappa B/metabolism , Signal Transduction , Genetic Diseases, Inborn/diagnostic imaging , Genetic Diseases, Inborn/therapy , Humans , Osteoclasts/metabolism , Osteoclasts/pathology , Receptor Activator of Nuclear Factor-kappa B/genetics , Signal Transduction/geneticsABSTRACT
OBJECTS: To simulate and compare salivary flow patterns over a tooth surface bonded with different orthodontic appliances using computational fluid dynamics (CFD) and investigate the impact of bracket design on salivary flow in relation to peri-bracket bacterial accumulation. SETTING AND SAMPLE POPULATION: The models were constructed using computed tomography (CT) data of 81 patients scheduled for fixed orthodontic treatment: 27 patients (10 males, 17 females) for the metal Victory MBT™ bracket; 27 patients (seven males, 20 females) for the ceramic Clarity MBT™ bracket; 27 patients (15 males, 12 females) for the Mini Uni-Twin (MUT) bracket. METHODS: The salivary flow patterns were simulated by CFD and compared between the groups and the model predictions were validated using a bacteriological experiment. RESULTS: The MUT bracket was associated with the greatest number of low salivary velocity areas, as it is designed with a connector between double tie wings and a right contact angle between tooth surface and bracket base. After archwire placement, the centred slot in the bracket and the bilateral sites around the bracket had higher bacterial retention and needed special oral hygiene measures. The obtuse contact angle of the ceramic bracket formed a pocket structure in the tie-wing area, retarding salivary flow and contributing to bacteria retention. CONCLUSION: With the evaluation of CFD models, we demonstrate that salivary flow patterns over a tooth surface with a bracket vary with bracket designs and further promote bacterial retention in specific locations, suggesting the need for additional oral hygiene measures for specific bracket types.
Subject(s)
Orthodontic Brackets , Bacteria , Female , Humans , Hydrodynamics , Male , Materials Testing , Orthodontic Appliance Design , Orthodontic WiresABSTRACT
Connexin 43 (Cx43)-associated gap junctions form electrical and mechanical conduits between adjacent ventricular cardiomyocytes, ensuring coordinate electrical excitation and synchronic contraction for each heartbeat. Cx43 dephosphorylation is a characteristic of ischemia, arrhythmia, and a failing and aging myocardium, but the exact phosphosite(s) triggering myocardial apoptosis and electrical disturbance and its underlying mechanisms are unclear. We previously found that Cx43-serine 282 phosphorylation (pS282) can regulate cardiomyocyte survival and electrical stability. Here, we investigated the hypothesis that S282 dephosphorylation occurs in and contributes to ischemia/reperfusion (I/R)-induced cardiac injury. We found enhanced Cx43-pS262 and Cx43-pS368 but decreased Cx43-pS282 in rat hearts subjected to I/R (30 min/2 h). I/R rats had ventricular arrhythmias and myocardial apoptosis with activation of the p38 mitogen-activated protein kinase (p38)/factor-associated suicide (Fas)/Fas-associating protein with a novel death domain (FADD) pathway. Similarly, S282 dephosphorylation, abnormal Ca2+ transients, cell apoptosis and p38/Fas/FADD activation also occurred in neonatal rat ventricular myocytes exposed to anoxia/reoxygenation (12/6 h). To confirm the causative role of S282 dephosphorylation in cardiac injury, rat hearts were intramyocardially injected with a virus carrying the S282 mutant substituted with alanine (S282A), thus causing arrhythmias and reducing cardiac output and myocardial apoptosis with p38/Fas/FADD pathway activation. Moreover, Cx43-S282A+/- mice displayed arrhythmias and impaired cardiac output with global myocardial apoptosis. Our findings revealed that Cx43 dephosphorylation at S282 triggers arrhythmias and, at least partly, contributes to cardiomyocyte death upon I/R by activating the p38/Fas/FADD pathway, providing a novel molecular mechanism and potential target for protecting against cardiac I/R injury.
Subject(s)
Arrhythmias, Cardiac/metabolism , Connexin 43/metabolism , Myocardial Reperfusion Injury/physiopathology , Myocytes, Cardiac/pathology , Animals , Apoptosis/physiology , Arrhythmias, Cardiac/physiopathology , Male , Myocardial Reperfusion Injury/metabolism , Phosphorylation , Rats , Rats, Sprague-Dawley , Serine/metabolismABSTRACT
BACKGROUND/AIMS: Upon Ca2+ store depletion, stromal interaction molecule 1 (STIM1) oligomerizes, redistributes near plasmalemma to interact with Ca2+ selective channel-forming subunit (Orai1) and initiates store-operated Ca2+ entry (SOCE). Ca2+/calmodulin-dependent protein kinase II (CaMKII) is a regulator of SOCE, but how CaMKII regulates SOCE remains obscure. METHODS: Using Fura2, confocal microscopy, co-immunoprecipitation, specific blocker and overexpression/knockdown approaches, we evaluated STIM1 aggregation and its interaction with Orai1, and SOCE upon Ca2+ store depletion in thapsigargin (TG) treated HEK293 and HeLa cells. RESULTS: Overexpression of CaMKIIδ enhanced TG-induced STIM1 co-localization and interaction with Orai1 as well as SOCE. In contrast, CaMKIIδ knockdown and a specific inhibitor of CaMKII suppressed them. In addition, overexpression or knockdown of CaMKIIδ in TG treated cells exhibited increased or reduced STIM1 clustering and plasmalemma redistribution, respectively. CONCLUSION: CaMKII up-regulates SOCE by increasing STIM1 aggregation and interaction with Orai1. This study provides an additional insight into SOCE regulation and a potential mechanism for CaMKII involvement in some pathological situations through crosstalk with SOCE.
Subject(s)
Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism , Calcium/metabolism , Neoplasm Proteins/metabolism , ORAI1 Protein/metabolism , Stromal Interaction Molecule 1/metabolism , Calcium-Calmodulin-Dependent Protein Kinase Type 2/antagonists & inhibitors , Calcium-Calmodulin-Dependent Protein Kinase Type 2/genetics , HEK293 Cells , HeLa Cells , Humans , Immunoprecipitation , Phosphorylation/drug effects , Protein Binding , Protein Kinase Inhibitors/pharmacology , Protein Multimerization/drug effects , RNA Interference , RNA, Small Interfering/metabolism , Thapsigargin/pharmacologyABSTRACT
BACKGROUND/AIMS: Stromal interacting molecule-1 (STIM1) aggregation and redistribution to plasma membrane to interact with Orai1 constitute the core mechanism of store-operated Ca2+ entry (SOCE). Previous study has revealed that calsequestrin-1 (CSQ1) regulates SOCE in HEK293 cells through interacting with STIM1 and inhibiting STIM1/Orai1 interaction. Here, we further investigate how CSQ1/STIM1 interaction affects SOCE. METHODS: Using confocal microscopy, STIM1 aggregation and co-localizations with CSQ1 or Orai1 upon Ca2+ store depletion by thapsigargin were measured and quantified by Imaris software in HeLa cells transfected with different CSQ1 mutants. The interactions of CSQ1/STIM1 and STIM1/Orai1, and internal Ca2+ changes were detected by co-immunoprecipitation and Fura2, respectively. RESULTS: Wt-CSQ1 overexpression significantly reduced STIM1 clustering in the perimembrane and cytosolic regions, whereas over-expression of a C-terminal amino acid 362-396 deletion mutant (C35) did not. Consistently, a significant depression of SOCE, increased CSQ1 monomerization and CSQ1/STIM1 interaction, and a reduced STIM1/Orai1 association were observed in wt-CSQ1 but not in C35-transfected cells. Additionally, mutant lacking C-terminal AA 388-396 deletion exerted weaker potency in inhibiting STIM1 aggregation and association with Orai1 than wt-CSQ1. CONCLUSIONS: Our results demonstrate that CSQ1 monomers suppress SOCE by interacting with STIM1 and attenuating STIM1 aggregation via its C-terminal amino acid 362-396.
Subject(s)
Calcium-Binding Proteins/metabolism , Calcium/metabolism , Mitochondrial Proteins/metabolism , Neoplasm Proteins/metabolism , Stromal Interaction Molecule 1/metabolism , Calcium/analysis , Calcium-Binding Proteins/analysis , Calsequestrin , Cations, Divalent/analysis , Cations, Divalent/metabolism , HeLa Cells , Humans , Mitochondrial Proteins/analysis , Neoplasm Proteins/analysis , ORAI1 Protein/analysis , ORAI1 Protein/metabolism , Protein Aggregates , Protein Interaction Maps , Stromal Interaction Molecule 1/analysisABSTRACT
AIM: We have shown that low-dose gadolinium chloride (GdCl3) abolishes arachidonic acid (AA)-induced increase of cytoplasmic Ca(2+), which is known to play a crucial role in myocardial ischemia/reperfusion (I/R) injury. The present study sought to determine whether low-dose GdCl3 pretreatment protected rat myocardium against I/R injury in vitro and in vivo. METHODS: Cultured neonatal rat ventricular myocytes (NRVMs) were treated with GdCl3 or nifedipine, followed by exposure to anoxia/reoxygenation (A/R). Cell apoptosis was detected; the levels of related signaling molecules were assessed. SD rats were intravenously injected with GdCl3 or nifedipine. Thirty min after the administration the rats were subjected to LAD coronary artery ligation followed by reperfusion. Infarction size, the release of serum myocardial injury markers and AA were measured; cell apoptosis and related molecules were assessed. RESULTS: In A/R-treated NRVMs, pretreatment with GdCl3 (2.5, 5, 10 µmol/L) dose-dependently inhibited caspase-3 activation, death receptor-related molecules DR5/Fas/FADD/caspase-8 expression, cytochrome c release, AA release and sustained cytoplasmic Ca(2+) increases induced by exogenous AA. In I/R-treated rats, pre-administration of GdCl3 (10 mg/kg) significantly reduced the infarct size, and the serum levels of CK-MB, cardiac troponin-I, LDH and AA. Pre-administration of GdCl3 also significantly decreased the number of apoptotic cells, caspase-3 activity, death receptor-related molecules (DR5/Fas/FADD) expression and cytochrome c release in heart tissues. The positive control drug nifedipine produced comparable cardioprotective effects in vitro and in vivo. CONCLUSION: Pretreatment with low-dose GdCl3 significantly attenuates I/R-induced myocardial apoptosis in rats by suppressing activation of both death receptor and mitochondria-mediated pathways.
Subject(s)
Gadolinium/therapeutic use , Myocardial Reperfusion Injury/drug therapy , Animals , Apoptosis/drug effects , Arachidonic Acid/pharmacology , Caspase 3/metabolism , Enzyme Activation , Gadolinium/administration & dosage , Male , Mitochondria, Heart/drug effects , Mitochondria, Heart/metabolism , Myocardial Reperfusion Injury/pathology , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/pathology , Rats, Sprague-Dawley , Receptors, TNF-Related Apoptosis-Inducing Ligand/metabolism , Signal Transduction/drug effectsABSTRACT
Coronary artery perforation (CAP) is an infrequent yet potentially life-threatening complication of percutaneous coronary intervention. We report, for the first time, two cases of successful closure of guidewire-induced distal CAP with silk suture embolization using a microcatheter. This technique appears to be safe, simple, and effective for the treatment of distal guidewire perforations, even in refractory cases.
Subject(s)
Coronary Vessels/injuries , Embolization, Therapeutic/instrumentation , Heart Injuries/therapy , Percutaneous Coronary Intervention/adverse effects , Silk , Sutures , Vascular System Injuries/therapy , Aged , Cardiac Catheters , Coronary Angiography , Coronary Vessels/diagnostic imaging , Equipment Design , Female , Heart Injuries/diagnosis , Humans , Male , Middle Aged , Miniaturization , Treatment Outcome , Vascular System Injuries/diagnosisABSTRACT
OBJECTIVES: The primary aim of this study was to determine whether wave intensity can discriminate cases of eccentric hypertrophy in patients with essential hypertension who have varied left ventricular configurations. METHODS: A total of 155 hypertensive patients with different ventricular configurations (27 normal configuration, 42 concentric remodeling, 62 concentric hypertrophy, and 24 eccentric hypertrophy) were recruited. We performed a noninvasive wave intensity analysis of the common carotid artery and conventional echocardiography. Blood pressure and flow velocity were measured in the right carotid artery of all patients. RESULTS: The left ventricular ejection fraction (LVEF) in the eccentric hypertrophy group was significantly lower than the values in the other groups (P < .05). The R-W1 interval/W1-W2 interval ratio (where W1 indicates the first positive peak and W2 the second positive peak) in the eccentric hypertrophy group was much higher than the values in the other groups (P < .05). However, there were no significant differences in W1, W2, and negative area among these groups. Pearson correlation analysis showed that R-W1/W1-W2, R-W1, and W1-W2were correlated with the LVEF, whereas there was no correlation between W1, W2, negative area, and the reflection coefficient with the LVEF. CONCLUSIONS: We propose that by using the R-W1/W1-W2 ratio, wave intensity analysis can identify hypertensive patients with eccentric hypertrophy without the need for echocardiography.