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1.
Bull Tokyo Dent Coll ; 64(2): 67-74, 2023 Jun 10.
Article in English | MEDLINE | ID: mdl-37183009

ABSTRACT

Dens invaginatus is a morphological abnormality of the tooth that results from a developmental anomaly during tooth formation, in which part of the enamel and dentin of the crown invaginates into the pulp cavity. This report describes a case of a maxillary lateral incisor with apical periodontitis apparently caused by Oehlers Type III dens invaginatus. The patient was a 69-year-old man who visited our clinic complaining of discomfort in the maxillary right lateral incisor. Cone-beam computed tomography (CBCT) revealed dens invaginatus of the maxillary lateral incisor and a sinus tract in the maxillary central incisor region, which was derived from apical periodontitis of the maxillary lateral incisor. The dens invaginatus was accompanied by a complex root canal morphology. Treatment, which was performed using a dental surgical microscope, had a favorable outcome. The patient remains in good condition at 1 year postoperatively.


Subject(s)
Dens in Dente , Periapical Periodontitis , Male , Humans , Aged , Dental Pulp Cavity/abnormalities , Dens in Dente/diagnostic imaging , Dens in Dente/therapy , Dens in Dente/complications , Incisor/diagnostic imaging , Incisor/surgery , Incisor/abnormalities , Root Canal Therapy/methods , Periapical Periodontitis/diagnostic imaging , Periapical Periodontitis/surgery , Inflammation , Cone-Beam Computed Tomography/methods
2.
Am J Physiol Renal Physiol ; 321(3): F278-F292, 2021 09 01.
Article in English | MEDLINE | ID: mdl-34338030

ABSTRACT

The relevance of primary cilia shortening in kidney disease and its pathomechanism are largely unknown. Tubular damage in acute kidney injury (AKI) is strongly associated with mitochondrial dysfunction. Thus, we investigated the interaction between primary cilia and mitochondria in cisplatin-induced AKI mouse models. We observed that the expression of intraflagellar transport 88 (IFT88), a ciliary maintenance protein, was decreased in the renal cortex following tubular damage due to cisplatin-induced AKI. This result was consistent with the decreased IFT88 expression in cisplatin-treated RPTEC/TERT1 cells (human primary proximal tubular cells) parallel to the shortening of primary cilia, suggesting a causative link between tubular damage and IFT88-mediated cilia regulation. To address the effect of impaired primary cilia with decreased IFT88 expression on tubular function, RPTEC/TERT1 cells treated with cisplatin and knocked down for IFT88 using siRNA (IFT88-KD) were assessed for phenotypic changes and mitochondrial metabolic function. Both cisplatin and IFT88-KD caused primary cilia shortening, downregulated mitochondrial oxidative phosphorylation capacity, and had defective fatty acid oxidation and decreased ATP production. Furthermore, IFT88 overexpression enhanced mitochondrial respiration, which partially counteracted cisplatin-induced defective fatty acid oxidation. These results are indicative of the contribution of IFT88 to mitochondrial homeostasis. Our findings suggest that tubular mitochondrial dysfunction in cisplatin-induced AKI is mediated, at least in part, by a decrease in IFT88 expression with primary cilia shortening. That is, tubular mitochondrial damage followed by tubular injury in AKI may occur through alteration of IFT88 expression and subsequent ciliary shortening in tubular cells.NEW & NOTEWORTHY Here, we demonstrated organelle cross-talk between primary cilia and mitochondria of proximal tubular cells in cisplatin-induced acute kidney injury. The primary cilia-mitochondria interaction may open new avenues for the development of novel therapeutic approaches in the treatment of acute kidney injury.


Subject(s)
Acute Kidney Injury/metabolism , Cilia/metabolism , Cisplatin/pharmacology , Tumor Suppressor Proteins/metabolism , Acute Kidney Injury/chemically induced , Animals , Apoptosis/genetics , Apoptosis/physiology , Cilia/genetics , Cisplatin/metabolism , Epithelial Cells/metabolism , Kidney Tubules/metabolism , Mice , Mitochondria/drug effects , Mitochondria/metabolism , Tumor Suppressor Proteins/genetics
3.
J Am Soc Nephrol ; 32(7): 1599-1615, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33875568

ABSTRACT

BACKGROUND: The sympathetic nervous system regulates immune cell dynamics. However, the detailed role of sympathetic signaling in inflammatory diseases is still unclear because it varies according to the disease situation and responsible cell types. This study focused on identifying the functions of sympathetic signaling in macrophages in LPS-induced sepsis and renal ischemia-reperfusion injury (IRI). METHODS: We performed RNA sequencing of mouse macrophage cell lines to identify the critical gene that mediates the anti-inflammatory effect of ß2-adrenergic receptor (Adrb2) signaling. We also examined the effects of salbutamol (a selective Adrb2 agonist) in LPS-induced systemic inflammation and renal IRI. Macrophage-specific Adrb2 conditional knockout (cKO) mice and the adoptive transfer of salbutamol-treated macrophages were used to assess the involvement of macrophage Adrb2 signaling. RESULTS: In vitro, activation of Adrb2 signaling in macrophages induced the expression of T cell Ig and mucin domain 3 (Tim3), which contributes to anti-inflammatory phenotypic alterations. In vivo, salbutamol administration blocked LPS-induced systemic inflammation and protected against renal IRI; this protection was mitigated in macrophage-specific Adrb2 cKO mice. The adoptive transfer of salbutamol-treated macrophages also protected against renal IRI. Single-cell RNA sequencing revealed that this protection was associated with the accumulation of Tim3-expressing macrophages in the renal tissue. CONCLUSIONS: The activation of Adrb2 signaling in macrophages induces anti-inflammatory phenotypic alterations partially via the induction of Tim3 expression, which blocks LPS-induced systemic inflammation and protects against renal IRI.

4.
Sci Rep ; 10(1): 9472, 2020 06 11.
Article in English | MEDLINE | ID: mdl-32528023

ABSTRACT

The efficacy of prior activation of an anti-inflammatory pathway called the cholinergic anti-inflammatory pathway (CAP) through vagus nerve stimulation (VNS) has been reported in renal ischemia-reperfusion injury models. However, there have been no reports that have demonstrated the effectiveness of VNS after injury. We investigated the renoprotective effect of VNS in a cisplatin-induced nephropathy model. C57BL/6 mice were injected with cisplatin, and VNS was conducted 24 hours later. Kidney function, histology, and a kidney injury marker (Kim-1) were evaluated 72 hours after cisplatin administration. To further explore the role of the spleen and splenic macrophages, key players in the CAP, splenectomy, and adoptive transfer of macrophages treated with the selective α7 nicotinic acetylcholine receptor agonist GTS-21 were conducted. VNS treatment significantly suppressed cisplatin-induced kidney injury. This effect was abolished by splenectomy, while adoptive transfer of GTS-21-treated macrophages improved renal outcomes. VNS also reduced the expression of cytokines and chemokines, including CCL2, which is a potent chemokine attracting monocytes/macrophages, accompanied by a decline in the number of infiltrating macrophages. Taken together, stimulation of the CAP protected the kidney even after injury in a cisplatin-induced nephropathy model. Considering the feasibility and anti-inflammatory effects of VNS, the findings suggest that VNS may be a promising therapeutic tool for acute kidney injury.


Subject(s)
Acute Kidney Injury/chemically induced , Acute Kidney Injury/physiopathology , Cisplatin/pharmacology , Macrophages/physiology , Vagus Nerve/physiopathology , Acute Kidney Injury/metabolism , Animals , Anti-Inflammatory Agents/pharmacology , Benzylidene Compounds/pharmacology , Cytokines/metabolism , Inflammation/metabolism , Inflammation/physiopathology , Kidney/drug effects , Kidney/metabolism , Kidney/physiopathology , Macrophages/drug effects , Macrophages/metabolism , Male , Mice , Mice, Inbred C57BL , Pyridines/pharmacology , Reperfusion Injury/chemically induced , Reperfusion Injury/metabolism , Reperfusion Injury/physiopathology , Spleen/drug effects , Spleen/metabolism , Spleen/physiopathology , Vagus Nerve/metabolism , Vagus Nerve Stimulation/methods , alpha7 Nicotinic Acetylcholine Receptor/metabolism
5.
Bull Tokyo Dent Coll ; 61(2): 127-133, 2020 Jul 04.
Article in English | MEDLINE | ID: mdl-32507779

ABSTRACT

The recent use of cone beam computed tomography (CBCT) in the field of dentistry to obtain 3-dimensional (3D) images has enabled more effective examination and diagnosis in endodontic treatment. Such information has also been reported to be of benefit in surgical endodontic treatment such as intentional replantation. Here, we report a case of intentional replantation with the assistance of CBCT in which a good therapeutic outcome was achieved. The patient was a 30-year-old woman who visited our hospital with the chief complaint of spontaneous pain in the right maxillary first molar. Dental radiographs revealed a radiolucent area in the apical portion of the distal root, and a radiopaque area thought to be a broken shard from a small surgical instrument measuring approximately 1.5 mm in length. The shard was located outside the distal apical foramen. Based on these findings, the diagnosis was acute suppurative apical periodontitis of the right maxillary first molar. Infected root canal therapy was subsequently commenced. The patient's symptoms showed no improvement, however, and the pain persisted. Therefore, dental CBCT was performed to obtain 3D images, which confirmed a radiopaque area thought to be a broken shard from a small surgical instrument located outside the apical foramen of the distal root and facing in a direction that made it impossible to remove from the root canal. Because the patient's symptoms had shown no improvement and a foreign body was observed outside the apical foramen, intentional replantation combined with root resection was performed with informed consent. At a 1-year follow-up visit, progress was good, and there were no reported symptoms or signs. When reaching a diagnosis is difficult based on clinical findings and dental radiographs alone, the 3D images provided by CBCT offer a means of securing a more reliable diagnosis, allowing planning of treatment to be more effective.


Subject(s)
Foreign Bodies , Periapical Periodontitis , Spiral Cone-Beam Computed Tomography , Adult , Cone-Beam Computed Tomography , Female , Humans , Molar , Root Canal Therapy , Tooth Apex , Tooth Replantation
6.
Clin J Gastroenterol ; 13(5): 693-696, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32588330

ABSTRACT

MitraClip procedure is an effective treatment for mitral regurgitation, performed globally. During the MitraClip procedure, transesophageal echocardiography is an essential modality to perform the operation safely. Although a few transesophageal echocardiography-related complications, such as esophageal hematoma, have been reported, there are no reports on massive esophageal bleeding after the MitraClip procedure. We present the first case of massive esophageal hemorrhage caused by transesophageal echocardiography after a MitraClip procedure and the successful treatment by balloon compression using a Sengstaken-Blakemore tube.


Subject(s)
Balloon Occlusion , Mitral Valve Insufficiency , Echocardiography, Transesophageal , Esophagus , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Hemorrhage/therapy , Humans , Mitral Valve Insufficiency/diagnostic imaging , Mitral Valve Insufficiency/etiology , Mitral Valve Insufficiency/surgery , Treatment Outcome
7.
Cell Rep ; 29(5): 1261-1273.e6, 2019 10 29.
Article in English | MEDLINE | ID: mdl-31665638

ABSTRACT

Acute kidney injury (AKI) is characterized by mitochondrial dysfunction and activation of the innate immune system. The cyclic GMP-AMP synthase (cGAS) stimulator of interferon genes (STING) pathway detects cytosolic DNA and induces innate immunity. Here, we investigate the role of mitochondrial damage and subsequent activation of the cGAS-STING pathway using a genetically engineered animal model of cisplatin-induced AKI and cultured tubular cells. Cisplatin induced mtDNA leakage into the cytosol-probably through BCL-2-like protein 4 (BAX) pores in the mitochondrial outer membrane-in tubules, with subsequent activation of the cGAS-STING pathway, thereby triggering inflammation and AKI progression, which is improved in STING-deficient mice. STING knockdown in cultured tubular cells ameliorates inflammatory responses induced by cisplatin. mtDNA depletion and repletion studies support tubular inflammatory responses via the cGAS-STING signal activation by cytosolic mtDNA. Therefore, we conclude that mitochondrial dysfunction and subsequent activation of the mtDNA-cGAS-STING pathway is a critical regulator of kidney injury.


Subject(s)
Acute Kidney Injury/metabolism , Acute Kidney Injury/pathology , Inflammation/pathology , Membrane Proteins/metabolism , Mitochondria/pathology , Nucleotidyltransferases/metabolism , Acute Kidney Injury/chemically induced , Animals , Cell Line , Cell Movement/drug effects , Cisplatin/adverse effects , Cytosol/metabolism , DNA, Mitochondrial/metabolism , Humans , Kidney Tubules/drug effects , Kidney Tubules/pathology , Male , Mice, Inbred C57BL , Mitochondria/drug effects , Mitochondria/metabolism , Neutrophils/drug effects , Neutrophils/metabolism , Signal Transduction/drug effects , bcl-2-Associated X Protein/metabolism
8.
Bull Tokyo Dent Coll ; 57(3): 133-42, 2016.
Article in English | MEDLINE | ID: mdl-27665691

ABSTRACT

Periapical periodontitis usually results from microbial infection, with these microorganisms occasionally migrating to the root canal, which can lead to further, potentially life-threatening, complications. Here, the susceptibility of 27 bacterial strains to various antimicrobial agents was evaluated. These strains comprised 13 species; 16 of the strains were clinical isolates from periapical lesions. Each strain was inoculated onto blood agar plates containing one of the antimicrobial agents. The plates were incubated anaerobically at 37°C for 96 hr and the minimal inhibitory concentrations (MICs) determined. Ten strains required an MIC of 32 µg/ml or greater for amoxicillin, 6 for cefmetazole, and 5 for cefcapene among ß-lactam antibiotics; 8 strains required an MIC of 32 µg/ml or greater for clindamycin, 4 for azithromycin, and 11 for clarithromycin among macrolide antibiotics; 3 strains required an MIC of 32 µg/ml or greater for ciprofloxacin and 2 for ofloxacin among fluoroquinolones. The effect of cefcapene on 5 strains was evaluated after biofilm formation to investigate the relationship between biofilm formation and susceptibility. All strains showed a decrease in susceptibility after biofilm formation. The results revealed that several antimicrobial agents commonly used in a clinical setting, including amoxicillin, cefmetazole, and clindamycin, are potentially effective in the treatment of orofacial odontogenic infections. The development of resistant strains, however, means that this can no longer be guaranteed. In addition, azithromycin, ciprofloxacin, and ofloxacin were more effective than the 3 ß-lactam antibiotics tested. These results suggest that sensitivity testing is needed if odontogenic infections are to be treated safely and effectively.


Subject(s)
Drug Resistance, Bacterial , Periapical Periodontitis/microbiology , Actinomyces/drug effects , Amoxicillin/pharmacology , Anti-Bacterial Agents/pharmacology , Azithromycin/pharmacology , Biofilms/drug effects , Campylobacter/drug effects , Cefmetazole/pharmacology , Cephalosporins/pharmacology , Ciprofloxacin/pharmacology , Clarithromycin/pharmacology , Clindamycin/pharmacology , Fusobacteria/drug effects , Haemophilus/drug effects , Humans , Klebsiella/drug effects , Microbial Sensitivity Tests , Ofloxacin/pharmacology , Porphyromonas/drug effects , Propionibacterium/drug effects , Staphylococcus hominis/drug effects , Veillonella/drug effects
9.
Bull Tokyo Dent Coll ; 57(4): 291-297, 2016.
Article in English | MEDLINE | ID: mdl-28049977

ABSTRACT

Apical periodontitis is usually diagnosed based on clinical findings and dental X-rays. Recently, however, dental cone beam computed tomography (CBCT), which provides 3-D images of the maxillofacial region, has enabled dentists to examine patients undergoing endodontic therapy more effectively, improving diagnostic accuracy. Here, we describe a positive treatment outcome achieved using CBCT to diagnose apical periodontitis of the maxillary premolars, which had proven difficult to diagnose based on clinical findings and dental radiography alone. The patient was a 42-year-old Japanese man who presented with the chief complaint of gingival swelling in the maxillary right premolar region. Our initial diagnosis, based on clinical findings and dental X-ray, was apical periodontitis of the maxillary right second premolar, and treatment was started. However, after the patient failed to respond to the treatment, CBCT was performed. Based on these new findings, the diagnosis was changed to one of apical periodontitis of the upper right first premolar, and the patient was treated accordingly. Previous studies have described the complex anatomical morphology of the upper premolars, noting multiple roots and variation in the morphology of the root canals. The 3-D images provided by dental CBCT allow better assessment of oral conditions than the traditional 2-D images provided by dental X-rays, which in turn enables the dentist to better select the most appropriate treatment. Here, the patient showed no symptoms and was progressing well at a 6-month follow-up visit. The present results indicate that when clinical findings and dental X-rays alone are insufficient to allow a secure diagnosis, CBCT offers an effective alternative which will enable the appropriate treatment to be selected more reliably.


Subject(s)
Cone-Beam Computed Tomography , Periapical Periodontitis/diagnostic imaging , Adult , Bicuspid/diagnostic imaging , Humans , Imaging, Three-Dimensional , Male
10.
Bull Tokyo Dent Coll ; 56(3): 169-75, 2015.
Article in English | MEDLINE | ID: mdl-26370577

ABSTRACT

Calcium deposited within a root canal due to exogenous stimuli may hamper root canal treatment. In endodontic treatment, an operating microscope allows the conditions within the root canal to be directly viewed and evaluated. This report describes a case in which an operating microscope was used to facilitate the excision of a calcified structure from within a root canal at an early stage in the treatment of an infection. An 18-year-old man was referred to our clinic due to suspected chronic suppurative apical periodontitis of the right maxillary central incisor. Periapical radiography confirmed the presence of a radioopaque structure inside the root canal that was likely to pose an obstacle to endodontic treatment. After opening the pulp chamber, an operating microscope was used to directly confirm the presence of the calcified structure in the root canal, which was removed using an ultrasonic tip. The infected root canal was treated using calcium hydroxide. Two months later, closure of the apical foramen as a result of calcification of the apical foramen was confirmed and the root canal filled. Using an operating microscope to directly view a structure posing an obstacle to root canal treatment made it possible to perform an excision while avoiding risks such as canal perforation.


Subject(s)
Calcinosis , Dental Pulp Cavity/microbiology , Root Canal Irrigants/therapeutic use , Root Canal Therapy , Adolescent , Endodontics , Humans , Infections/drug therapy , Male , Periapical Periodontitis/drug therapy , Tooth Apex
11.
Bull Tokyo Dent Coll ; 55(1): 33-7, 2014.
Article in English | MEDLINE | ID: mdl-24717928

ABSTRACT

The microflora in the periodontal pockets can affect the dental pulp and cause endodontic-periodontal lesions or retrograde pulpitis. Here we report an endodontic-periodontal lesion together with its bacterial profile. The lesion occurred in the maxillary right first molar of a 40-year-old woman who presented at our hospital complaining of a violent toothache since the previous night. Clinically, the tooth was caries-free and an electric pulp test showed it to be vital. The tooth showed signs of advanced periodontitis and the periodontal pocket was deep, reaching the apex of the palatal root. The clinical diagnosis was an endodontic-periodontal lesion with primary periodontal disease. Subsequent endodontic treatment comprised pulp extirpation and root canal filling, followed by periodontal treatment consisting of scaling and root planing. The tooth was finally restored with a full metal crown. No further signs of periodontal disease or periapical lesions have been observed to date. Bacteria were sampled from the root canal and periodontal pocket for a microbiological assessment using 16S rRNA gene-based PCR. Microbiologically, the profile of the bacterial species from the palatal root canal was similar to that from the periodontal pocket of the palatal root. Porphyromonas gingivalis, Fusobacterium nucleatum and Eikenella corrodens were detected in both samples. The occurrence of bacteria common to both sites in this patient further supports the proposition that periodontal disease is the definitive source of root canal infections. The present results suggest that a bacterial examination would be helpful in confirming and supporting the clinical diagnosis in such lesions.


Subject(s)
Periapical Periodontitis/microbiology , Periodontal Pocket/microbiology , Pulpitis/microbiology , Adult , Bacteroidaceae Infections/microbiology , Crowns , Dental Pulp Cavity/microbiology , Dental Scaling/methods , Eikenella corrodens/isolation & purification , Female , Fusobacterium Infections/microbiology , Fusobacterium nucleatum/isolation & purification , Gram-Negative Bacterial Infections/microbiology , Humans , Periapical Periodontitis/complications , Periodontal Pocket/complications , Porphyromonas gingivalis/isolation & purification , Pulpotomy/methods , Root Canal Obturation/methods , Root Planing/methods
12.
Bull Tokyo Dent Coll ; 54(2): 81-8, 2013.
Article in English | MEDLINE | ID: mdl-23903578

ABSTRACT

The purpose of this study was to clarify the viability of a novel method for removing debris from broken instruments from root canals using a laser apparatus. Laser welding was performed on stainless steel or nickel titanium files using an Nd:YAG laser. Retention force between the files and extractors was measured. Increase in temperature on the root surface during laser irradiation was recorded and the irradiated areas evaluated with a scanning electron microscope. Retention force on stainless steel was significantly greater than that on nickel titanium. The maximum temperature increase was 4.1°C. The temperature increase on the root surface was greater in the vicinity of the welded area than that at the apical area. Scanning electron microscopy revealed that the files and extractors were welded together. These results indicate that the laser welding method is effective in removing debris from broken instruments from root canals.


Subject(s)
Dental Pulp Cavity/pathology , Lasers, Solid-State , Root Canal Preparation/instrumentation , Welding/methods , Body Temperature , Dental Alloys/chemistry , Equipment Failure , Foreign Bodies/therapy , Hot Temperature , Humans , Microscopy, Electron, Scanning , Nickel/chemistry , Optical Fibers , Phase Transition , Stainless Steel/chemistry , Stress, Mechanical , Surface Properties , Titanium/chemistry , Tooth Apex/physiology , Tooth Root/physiology , Welding/instrumentation
13.
Cancer Res ; 70(15): 6283-92, 2010 Aug 01.
Article in English | MEDLINE | ID: mdl-20631070

ABSTRACT

Blood vessels deliver oxygen and nutrients to tissues, and vascular networks are spatially organized to meet the metabolic needs for maintaining homeostasis. In contrast, the vasculature of tumors is immature and leaky, resulting in insufficient delivery of nutrients and oxygen. Vasculogenic processes occur normally in adult tissues to repair "injured" blood vessels, leading us to hypothesize that bone marrow mononuclear cells (BMMNC) may be able to restore appropriate vessel function in the tumor vasculature. Culturing BMMNCs in endothelial growth medium resulted in the early outgrowth of spindle-shaped attached cells expressing CD11b/Flt1/Tie2/c-Kit/CXCR4 with proangiogenic activity. Intravenous administration of these cultured vascular proangiogenic cells (VPC) into nude mice bearing pancreatic cancer xenografts and Pdx1-Cre;LSL-Kras(G12D);p53(lox/+) genetically engineered mice that develop pancreatic ductal adenocarcinoma significantly reduced areas of hypoxia without enhancing tumor growth. The resulting vasculature structurally mimicked normal vessels with intensive pericyte coverage. Increases in vascularized areas within VPC-injected xenografts were visualized with an ultrasound diagnostic system during injection of a microbubble-based contrast agent (Sonazoid), indicating a functional "normalization" of the tumor vasculature. In addition, gene expression profiles in the VPC-transplanted xenografts revealed a marked reduction in major factors involved in drug resistance and "stemness" of cancer cells. Together, our findings identify a novel alternate approach to regulate abnormal tumor vessels, offering the potential to improve the delivery and efficacy of anticancer drugs to hypoxic tumors.


Subject(s)
Adenocarcinoma/blood supply , Adenocarcinoma/surgery , Bone Marrow Transplantation/methods , Pancreatic Neoplasms/blood supply , Pancreatic Neoplasms/surgery , Adenocarcinoma/metabolism , Angiogenic Proteins/biosynthesis , Animals , CD11b Antigen/biosynthesis , Cell Growth Processes/physiology , Cell Hypoxia/physiology , Cell Line, Tumor , Cytokines/biosynthesis , Drug Resistance, Neoplasm , Female , Humans , Mice , Mice, Nude , Neovascularization, Pathologic/metabolism , Neovascularization, Pathologic/pathology , Oxygen/blood , Oxygen/metabolism , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/metabolism , Phenotype , Xenograft Model Antitumor Assays
14.
PLoS One ; 5(1): e8824, 2010 Jan 21.
Article in English | MEDLINE | ID: mdl-20098680

ABSTRACT

BACKGROUND: The hedgehog (Hh) pathway has been implicated in the pathogenesis of cancer including pancreatic ductal adenocarcinoma (PDAC). Recent studies have suggested that the oncogenic function of Hh in PDAC involves signaling in the stromal cells rather than cell autonomous effects on the tumor cells. However, the origin and nature of the stromal cell type(s) that are responsive to Hh signaling remained unknown. Since Hh signaling plays a crucial role during embryonic and postnatal vasculogenesis, we speculated that Hh ligand may act on tumor vasculature specifically focusing on bone marrow (BM)-derived cells. METHODOLOGY/PRINCIPAL FINDINGS: Cyclopamine was utilized to inhibit the Hh pathway in human PDAC cell lines and their xenografts. BM transplants, co-culture systems of tumor cells and BM-derived pro-angiogenic cells (BMPCs) were employed to assess the role of tumor-derived Hh in regulating the BM compartment and the contribution of BM-derived cells to angiogenesis in PDAC. Cyclopamine administration attenuated Hh signaling in the stroma rather than in the cancer cells as reflected by decreased expression of full length Gli2 protein and Gli1 mRNA specifically in the compartment. Cyclopamine inhibited the growth of PDAC xenografts in association with regression of the tumor vasculature and reduced homing of BM-derived cells to the tumor. Host-derived Ang-1 and IGF-1 mRNA levels were downregulated by cyclopamine in the tumor xenografts. In vitro co-culture and matrigel plug assays demonstrated that PDAC cell-derived Shh induced Ang-1 and IGF-1 production in BMPCs, resulting in their enhanced migration and capillary morphogenesis activity. CONCLUSIONS/SIGNIFICANCE: We identified the BMPCs as alternative stromal targets of Hh-ligand in PDAC suggesting that the tumor vasculature is an attractive therapeutic target of Hh blockade. Our data is consistent with the emerging concept that BM-derived cells make important contributions to epithelial tumorigenesis.


Subject(s)
Angiopoietin-1/genetics , Bone Marrow Cells/metabolism , Carcinoma, Pancreatic Ductal/blood supply , Hedgehog Proteins/physiology , Insulin-Like Growth Factor I/genetics , Neovascularization, Pathologic/physiopathology , Pancreatic Neoplasms/blood supply , Animals , Bone Marrow Transplantation , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/pathology , Cell Line, Tumor , Hedgehog Proteins/antagonists & inhibitors , Immunohistochemistry , Mice , Mice, Nude , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Transplantation, Heterologous , Veratrum Alkaloids/pharmacology
15.
J Inorg Biochem ; 102(5-6): 1218-26, 2008.
Article in English | MEDLINE | ID: mdl-18234344

ABSTRACT

Intramolecular M(II)...H-C interactions (M(II)=Cu(II), Pd(II)) involving a side chain alkyl group of planar d8 and d9 metal complexes of the N-alkyl (R) derivatives of N,N-bis(2-pyridylmethyl)amine with an N3Cl donor set were established by structural and spectroscopic methods. The methyl group from the branched alkyl group (R=2,2-dimethylpropyl and 2-methylbutyl) axially interacts with the metal ion with the M...C and M...H distances of 3.056(3)-3.352(9) and 2.317(1)-2.606(1) A, respectively, and the M-H-C angles of 122.4-162.3 degrees . The Cu(II) complexes showing the interaction have a higher redox potential as compared with those without it, and the (1)H NMR signals of the interacting methyl group in Pd(II) complexes shifted downfield relative to the ligand signals. Dependence of the downshift values on the dielectric constants of the solvents used indicated that the M(II)...H-C interaction is mainly electrostatic in nature and may be regarded as a weak hydrogen bond. Implications for possible environmental effects of the leucine alkyl group at the type 1 Cu site of fungal laccase are also discussed.


Subject(s)
Alkanes/chemistry , Copper/chemistry , Methylamines/chemistry , Palladium/chemistry , Pyridines/chemistry , Crystallography, X-Ray , Hydrogen Bonding , Nuclear Magnetic Resonance, Biomolecular
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