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1.
World J Gastrointest Surg ; 16(4): 1203-1207, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38690061

RESUMO

BACKGROUND: Gastric wall necrosis is a rare complication of endoscopic treatment for bleeding gastric ulcer, which may exacerbate the patient's condition once it occurs and may even require surgical intervention for treatment. CASE SUMMARY: A 59-year-old man was admitted to our department with melena. Endoscopy revealed a giant ulcer in the gastric antrum with a visible vessel in its center, which was treated with sclerosants and tissue glue injection and resulted in necrosis of the gastric wall. CONCLUSION: Injection of sclerosants and tissue glue may lead to gastric wall necrosis, which is a serious complication. Therefore, before administering this treatment to patients, we should consider other more effective methods of hemostasis to avoid gastric wall necrosis.

2.
Int J Surg ; 110(6): 3285-3293, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38498404

RESUMO

PURPOSE: Previous studies have explored the role of immune cells on osteonecrosis. This Mendelian randomization (MR) study further assessed 731 immunocyte phenotypes on osteonecrosis, whether a causal relationship exists, and provides some evidence of causality. METHODS: The 731 immunocyte phenotypes and osteonecrosis data used in this study were obtained from their respective genome-wide association studies (GWAS). The authors used inverse variable weighting (IVW) as the primary analysis method. In addition, the authors simultaneously employed multiple analytical methods, including MR-Egger, weighted mode, simple mode, and weighted median, to strengthen the final results. Finally, sensitivity analyses were conducted to verify the stability and feasibility of the data. RESULTS: The results of the IVW method of MR analysis showed that 8 immunocyte phenotypes were positively associated with osteonecrosis [ P <0.05, odds ratio (OR) > 1]; 18 immunocyte phenotypes were negatively associated with osteonecrosis ( P <0.05, OR<1), none of which were heterogeneous or horizontally pleiotropic ( P > 0.05) or reverse causality. In addition to this, in reverse MR, osteonecrosis was positively associated with 10 additional immunocyte phenotypes ( P <0.05, OR > 1) and negatively associated with 14 immunocyte phenotypes ( P <0.05, OR<1). And none of them had heterogeneity and horizontal pleiotropy ( P > 0.05) or reverse causality. CONCLUSIONS: The authors demonstrated a complex causal relationship between multiple immune phenotypes and osteonecrosis through a comprehensive two-way, two-sample MR analysis, highlighting the complex pattern of interactions between the immune system and osteonecrosis.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Osteonecrose , Fenótipo , Humanos , Osteonecrose/genética , Osteonecrose/imunologia , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único
3.
World J Stem Cells ; 16(2): 137-150, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38455095

RESUMO

Blood vessels constitute a closed pipe system distributed throughout the body, transporting blood from the heart to other organs and delivering metabolic waste products back to the lungs and kidneys. Changes in blood vessels are related to many disorders like stroke, myocardial infarction, aneurysm, and diabetes, which are important causes of death worldwide. Translational research for new approaches to disease modeling and effective treatment is needed due to the huge socio-economic burden on healthcare systems. Although mice or rats have been widely used, applying data from animal studies to human-specific vascular physiology and pathology is difficult. The rise of induced pluripotent stem cells (iPSCs) provides a reliable in vitro resource for disease modeling, regenerative medicine, and drug discovery because they carry all human genetic information and have the ability to directionally differentiate into any type of human cells. This review summarizes the latest progress from the establishment of iPSCs, the strategies for differentiating iPSCs into vascular cells, and the in vivo transplantation of these vascular derivatives. It also introduces the application of these technologies in disease modeling, drug screening, and regenerative medicine. Additionally, the application of high-tech tools, such as omics analysis and high-throughput sequencing, in this field is reviewed.

4.
Brain Res Bull ; 209: 110909, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38402994

RESUMO

BACKGROUND: The efficacy of acupuncture at Zusanli (ST36) in alleviating lower-limb pain is widely acknowledged in clinical practice, while its underlying mechanism remains incompletely elucidated. Our previous research had revealed that the prompt analgesia induced by needling-ST36 was accompanied by expression alterations in certain exco-nucleotidases within the sciatic nerve. Building upon this finding, the current work focused on NTPDase1, the primary ecto-nucleotidase in the human body, which converts ATP into AMP. METHODS: A 20-min acupuncture was administered unilaterally at the ST36 on rats with acute ankle arthritis. The pain thresholds of the injured hind paws were determined. Pharmacological interference was carried out by introducing the corresponding reagents to the sciatic nerve. ATP levels around the excised nerve were measured using a luciferase-luciferin assay. Live calcium imaging, utilizing the Fura 2-related-F340/F380 ratio, was conducted on Schwann cells in excised nerves and cultured rat SCs line, RSC96 cells. RESULTS: The analgesic effect induced by needling-ST36 was impaired when preventing ATP degradation via inhibiting NTPDase1 activities with ARL67156 or Ticlopidine. Conversely, increasing NTPDase1 activities with Apyrase duplicated the acupuncture effect. Similarly, preventing the conversion of AMP to adenosine via suppression of NT5E with AMP-CP hindered the acupuncture effect. Unexpectedly, impeded ATP hydrolysis ability and diminished NTPDase1 expression were observed in the treated group. Agonism at P2Y2Rs with ATP, UTP, or INS365 resulted in anti-nociception. Contrarily, antagonism at P2Y2Rs with Suramin or AR-C 118925xx prevented acupuncture analgesia. Immunofluorescent labeling demonstrated that the treated rats expressed more P2Y2Rs that were predominant in Schwann cells. Suppression of Schwann cells by inhibiting ErbB receptors also prevented acupuncture analgesia. Finally, living imaging on the excised nerves or RSC96 cells showed that agonism at P2Y2Rs indeed led to [Ca2+]i rise. CONCLUSION: These findings strongly suggest that the analgesic mechanism of needling-ST36 on the hypersensation in the lower limb partially relies on NTPDase1 activities in the sciatic nerve. In addition to facilitating adenosine signaling in conjunction with NT5E, most importantly, NTPDase1 may provide an appropriate low-level ATP milieu for the activation of P2Y2R in the sciatic nerve, particularly in Schwann cells.


Assuntos
Analgesia por Acupuntura , Terapia por Acupuntura , Antígenos CD , Artrite , Ratos , Humanos , Animais , Apirase , Tornozelo , Dor , Nervo Isquiático/metabolismo , Trifosfato de Adenosina/metabolismo , Analgésicos , Monofosfato de Adenosina , Adenosina , Pontos de Acupuntura
5.
Front Biosci (Landmark Ed) ; 28(1): 1, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36722266

RESUMO

BACKGROUND: The activation of subcutaneous mast cells (MCs) helps to trigger the analgesic effect induced by acupuncture (AP), a traditional oriental therapy, that has been gradually accepted worldwide. This work aimed to reveal whether the serotonin (5-hydroxytryptamine, 5-HT) released from MCs plays an important role in this process, which has a controversial effect in the mechanism of pain. METHODS: In vivo tests, a 20-min session of AP was applied at Zusanli acupuncture point (acupoint) of acute ankle arthritis rats. Pain thresholds of the injured hindpaw were assessed to reflect the pain state, and the targeting substances in the interstitial space of the treated acupoint were sampled by microdialysis. In vitro experiments, exogenous 5-HT (exo-5-HT) was introduced to mediate adenosine triphosphate (ATP) release from cultured MCs. RESULTS: Needling promoted 5-HT accumulation at the Zusanli acupoint, which was prevented by sodium cromolyn. AP's analgesic effect was suppressed by the inhibition of 5-HT receptors at the acupoint, especially 5-HT1A subtype. In vitro tests, mechanical perturbation mimicking needling stimulation induced MCs to release 5-HT. 1 µM and 10 µM of exo-5-HT facilitated ATP release, which was restrained by blocking of 5-HT1 receptors rather than 5-HT3 receptors. As 5-HT, ATP and adenosine were also transiently accumulated in the treated acupoint during needling. Promoting ATP hydrolysis or activation adenosine A1 receptors duplicated AP analgesic effect. Finally, the inhibition of ATP receptors by suramin or pyridoxal phosphate-6-azo tetrasodium salt hydrate (PPADS) prevented AP analgesic effect. CONCLUSIONS: Our results suggest that MC-associated 5-HT release at acupoints contributes to AP analgesia, and the mediation of ATP secretion through 5-HT1A receptors might be the underlying mechanism at play. ATP could facilitate adenosine production or the propagation of needling signals.


Assuntos
Analgesia por Acupuntura , Artrite , Doença de Hashimoto , Animais , Ratos , Trifosfato de Adenosina , Serotonina , Pontos de Acupuntura , Mastócitos , Adenosina , Analgésicos
6.
Chin J Nat Med ; 20(7): 541-550, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35907653

RESUMO

The rhizome of giant taro (Alocasia macrorrhiza (L.) Schott), which is a highly adaptable wild plant, is a traditional Chinese herbal medicine. In the current study, the antiproliferative constituents of giant taro were investigated and six new (1-6) and four known piperidine alkaloids (7-10) were isolated from its rhizomes. Their chemical structures and absolute configurations were elucidated using various spectroscopic methods and the Mosher ester method. The isolated alkaloids were screened for the antiproliferative activity through MTT assay. The results indicated that piperidine alkaloids exerted potential antiproliferative activity against HepG2, AGS and MCF-7 tumor cells. Further researches showed that compounds 3-5 dose-dependently decreased the colony formation rate and induced the apoptosis of AGS cells, while compound 4 induced AGS cell death via the proapoptotic pathway. This study demonstrates that the piperidine alkaloids isolated from giant taro exhibit significant antitumor activity, which provides phytochemical evidence for further development and utilization.


Assuntos
Alcaloides , Alocasia , Alcaloides/análise , Alcaloides/farmacologia , Alocasia/química , Humanos , Piperidinas/farmacologia , Plantas , Rizoma/química
8.
Macromol Rapid Commun ; 39(24): e1800628, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30393901

RESUMO

Diselenide-bond-linked poly(N-isopropylacrylamide)-paclitaxel chemical conjugates are synthesized as a drug release carrier. The conjugates can self-assemble into "core-shell" nanoscaled micelles in aqueous solution and show thermal and redox dual-responsiveness. The conjugates can afford a high encapsulation efficiency of up to 72.3%, and deliver hydrophobic anticancer drug paclitaxel in a temperature and oxidization or reduction stress-mode. The in vitro 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and in vivo anticancer assays are performed to assess the cytotoxicity and anticancer activity of the conjugates, suggesting that the developed conjugates can be used to treat carcinoma as a novel and highly efficient drug delivery system.


Assuntos
Portadores de Fármacos/química , Paclitaxel/química , Polímeros/química , Acrilamidas/química , Sistemas de Liberação de Medicamentos/métodos , Interações Hidrofóbicas e Hidrofílicas , Oxirredução , Temperatura
9.
Front Pharmacol ; 9: 1525, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30670971

RESUMO

ß-sitosterol (BS), a major bioactive constituent present in plants, has shown potent anti-cancer activity against many human cancer cells, but its activity in pancreatic cancer (PC) cells has rarely been reported. Gemcitabine (GEM) is one of the first-line drugs for PC therapy, however, the treatment effect is not sustained due to prolonged drug resistance. In this study, we firstly studied the anti-PC activity and the mechanism of BS alone and in combination with GEM in vitro and in vivo. BS effectively inhibited the growth of PC cell lines by inhibiting proliferation, inducing G0/G1 phase arrest and apoptosis, suppressed the NF- kB activity, and increased expression of the protein Bax but decreased expression of the protein Bcl-2. Moreover, BS inhibited migration and invasion and downregulated epithelial-mesenchymal transition (EMT) markers and AKT/GSK-3ß signaling pathways. Furthermore, the combination of BS and GEM exhibited a significant synergistic effect in MIAPaCa-2 and BXPC-3 cells. More importantly, the combined treatment with BS and GEM lead to significant growth inhibition of PC xenografts. Overall, our data revealed a promising treatment option for PC by the combination therapy of BS and GEM.

10.
J Biomater Appl ; 30(10): 1473-84, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26939939

RESUMO

pH-Sensitive poly(methacrylic acid)-block-hydroxyl-terminated polybutadiene-block-poly(methacrylic acid) (PMAA-b-HTPB-b-PMAA) was synthesized and then hydrogenated in this work. The chain structure, phase behavior and thermal properties were characterized by(1)H NMR, FTIR, XRD, DSC, TGA, etc., and the physicochemical and biomedical properties were investigated via fluorescence spectroscopy, TEM, DLS, loading and release of drug and MTT, and so on. The experimental results indicated that the hydrogenation led to the change in the chain aggregate structure of hydrophobic HTPB blocks and the formation of more stable spherical core-shell micelle aggregates, and the critical micelle concentration decreased from 41.8 mg L(-1)before hydrogenation to 4.4 mg L(-1)after hydrogenation. The hydrogenated block copolymer micelle aggregates exhibited pH-triggered response, and could entrap twice as much hydrophobic drug as the unhydrided counterparts and the encapsulation efficiency was significantly improved, which makes them fine to meet the requirements for drug carriers. Therefore, the hydrogenated PMAA-b-HTPB-b-PMAA copolymer micelles as drug target release carriers can be well used in the field of prevention and treatment of cancers.


Assuntos
Butadienos/química , Preparações de Ação Retardada/química , Elastômeros/química , Ácidos Polimetacrílicos/química , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Portadores de Fármacos/química , Humanos , Concentração de Íons de Hidrogênio , Hidrogenação , Micelas , Neoplasias/tratamento farmacológico , Paclitaxel/administração & dosagem , Paclitaxel/farmacologia
11.
J Neuropathol Exp Neurol ; 75(2): 148-55, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26733584

RESUMO

Cylindrical spirals (CSs) are rare but distinct subsarcolemmal accumulations in skeletal muscle fibers. To date, CSs have been reported in only 16 patients with a variety of neuromuscular conditions. The origin and composition of CSs are unknown, although there are some morphologic similarities between CSs and tubular aggregates (TAs). To clarify the nature of CSs, we characterized the sarcoplasmic reticulum (SR) and other intracellular membrane system proteins in CSs of muscle biopsies from 2 adult Chinese siblings. Immunohistochemical studies revealed subsarcolemmal immunoreactivity for sarco/endoplasmic reticulum Ca2þ-ATPase 1 (SERCA 1) in the longitudinal SR, but no immunoreactivity for calsequestrin in the terminal cisternae or type 1 ryanodine receptor (RYR1) in the junctional SR. Muscles biopsied from 2 patients with TAs showed immunoreactivity not only for SERCA1 but also for other SR proteins, including calsequestrin and RYR1. CSs exhibited no immunoreactivity for the Golgi apparatus marker GM130, the nuclear membrane emerin, desmin, the autophagosome marker LC3, the lysosomal membrane marker LAMP2, dystrophin, or myosin. Our results suggest CSs may originate only from the longitudinal SR, whereas TAs are composed of both the junctional and longitudinal SR. Immunochemical staining with antibodies against calsequestrin and RYR1 help to distinguish these 2 pathological alterations.


Assuntos
Fibras Musculares Esqueléticas/ultraestrutura , Músculo Esquelético/ultraestrutura , Sarcolema/ultraestrutura , Retículo Sarcoplasmático/ultraestrutura , Adulto , Povo Asiático , Canais de Cálcio/biossíntese , Canais de Cálcio/genética , Moléculas de Adesão Celular/biossíntese , Moléculas de Adesão Celular/genética , Feminino , Humanos , Imuno-Histoquímica , Masculino , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/patologia , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Doenças Neuromusculares/genética , Doenças Neuromusculares/patologia , Proteína ORAI1 , Sarcolema/genética , Sarcolema/patologia , Retículo Sarcoplasmático/genética , Retículo Sarcoplasmático/patologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/biossíntese , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Molécula 1 de Interação Estromal , Molécula 2 de Interação Estromal
12.
Chemistry ; 21(8): 3264-70, 2015 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-25589007

RESUMO

An improved and practical procedure for the stereoselective synthesis of anti-ß-hydroxy-α-amino acids (anti-ßhAAs), by palladium-catalyzed sequential C(sp(3) )-H functionalization directed by 8-aminoquinoline auxiliary, is described. followed by a previously established monoarylation and/or alkylation of the ß-methyl C(sp(3) )-H of alanine derivative, ß-acetoxylation of both alkylic and benzylic methylene C(sp(3) )-H bonds affords various anti-ß-hydroxy-α-amino acid derivatives. As an example, the synthesis of ß-mercapto-α-amino acids, which are highly important to the extension of native chemical ligation chemistry beyond cysteine, is described. The synthetic potential of this protocol is further demonstrated by the synthesis of diverse ß-branched α-amino acids. The observed diastereoselectivities are strongly influenced by electronic effects of aromatic AAs and steric effects of the linear side-chain AAs, which could be explained by the competition of intramolecular C-OAc bond reductive elimination from Pd(IV) intermediates vs. intermolecular attack by an external nucleophile (AcO(-) ) in an SN 2-type process.


Assuntos
Alanina/química , Aminoácidos/síntese química , Aminoquinolinas/química , Paládio/química , Alquilação , Aminoácidos/química , Catálise , Estrutura Molecular , Estereoisomerismo
13.
Biochem Biophys Res Commun ; 455(3-4): 262-8, 2014 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-25449279

RESUMO

5-(3-Hydroxy-4-methoxyphenyl)-4-(3,4,5-trimethoxyphenyl)-3H-1,2-dithiol-3-one (COH-203) is a novel synthesized analogue of combretastatin A-4 that can be classified as a microtubule inhibitor. In this study, we evaluated the anti-hepatoma effect of COH-203 in vitro and in vivo and explored the underlying molecular mechanisms. COH-203 was shown to be more effective in inhibiting the proliferation of liver cancer cells compared with normal liver cells. COH-203 also displayed potent anti-tumor activity in a hepatocellular carcinoma xenograft model without significant toxicity. Mechanistic studies demonstrated that treatment with COH-203 induced mitotic arrest by inhibiting tubulin polymerization in BEL-7402 liver cancer cells. Long-term COH-203 treatment in BEL-7402 cells led to mitotic slippage followed by senescence via the p14(Arf)-p53-p21 and p16(INK4α)-Rb pathways. Furthermore, suppression of p53 via pifithrin-α (p53 inhibitor) and p53-siRNA attenuated COH-203-induced senescence in BEL-7402 cells, suggesting that COH-203 induced senescence p53-dependently. In conclusion, we report for the first time that COH-203, one compound in the combretastatin family, promotes anti-proliferative activity through the induction of p-53 dependent senescence. Our findings will provide a molecular rationale for the development of COH-203 as a promising anti-tumor agent.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Compostos Heterocíclicos com 1 Anel/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Estilbenos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Senescência Celular , Compostos Heterocíclicos com 1 Anel/química , Humanos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microtúbulos/efeitos dos fármacos , RNA Interferente Pequeno/metabolismo , Estilbenos/química , Tubulina (Proteína)/química , Moduladores de Tubulina/química , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Periodontol ; 73(7): 726-34, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12146531

RESUMO

BACKGROUND: Chemically modified tetracyclines (CMTs), devoid of antimicrobial activity, inhibit pathologically elevated collagenase activity both in vivo and in vitro. In the current study, doxycycline and 5 different CMTs were tested to prevent matrix metalloproteinase (MMP)-dependent periodontal tissue breakdown in an animal model of periodontitis. METHODS: Adult male rats received intragingival injections with either 10 microl of physiologic saline or Escherichia coli endotoxin (1 mg/ml) every other day for 6 days and were distributed into 8 treatment groups (12 rats/group): saline (S), endotoxin alone (E), E + CMT-1, E + CMT-3, E + CMT-4, E + CMT-7, E + CMT-8, and doxycycline. All animals were treated daily with 1 ml of 2% carboxymethyl cellulose (CMC) alone or containing one of the above-mentioned CMTs (2 mg/day) orally. The gingival tissues were removed, extracted, and assayed for gelatinase (GLSE). Some rat maxillary jaws from each treatment group were fixed in buffered formalin and processed for histology and immunohistochemistry for the cytokines tumor necrosis factor (TNF), interleukin (IL)-1, and IL-6, and MMP-2 and MMP-9. RESULTS: Endotoxin injection induced elevated GLSE activity (functional assay and osteoclast-mediated bone resorption), the former identified as predominantly MMP-9 (92 kDa GLSE) by gelatin zymography. All 6 tetracyclines (2 mg/day) inhibited periodontal breakdown in the following order of efficacy: CMT-8 > CMT- 1 > CMT-3 > doxycycline > CMT-4 > CMT-7. Immunohistochemistry was positive for TNF, IL-1, and IL-6 in the inflammatory cells from untreated endotoxin rat tissues, whereas treatment with CMTs decreased the number of immuno-positive stained cells for cytokines and MMPs. The in vivo efficacy of these drugs varied with CMT structure and was significantly correlated with bone resorption: r2 = -0.77, P<0.01; gelatinase inhibitory activity: r2 = -0.84, P <0.01; and serum drug concentrations. CONCLUSION: Since both conventional (antimicrobial) and non-antimicrobial tetracyclines inhibited periodontal bone resorption induced by endotoxin injection, MMP-mediated bone loss in this model can be prevented by inhibition of MMPs.


Assuntos
Perda do Osso Alveolar/tratamento farmacológico , Perda do Osso Alveolar/enzimologia , Gelatinases/antagonistas & inibidores , Periodontite/tratamento farmacológico , Periodontite/enzimologia , Inibidores de Proteases/farmacologia , Tetraciclinas/farmacologia , Perda do Osso Alveolar/induzido quimicamente , Análise de Variância , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Modelos Animais de Doenças , Doxiciclina/farmacologia , Doxiciclina/uso terapêutico , Eletroforese em Gel de Poliacrilamida , Endotoxinas , Técnicas Imunoenzimáticas , Interleucinas/análise , Masculino , Periodontite/induzido quimicamente , Ratos , Ratos Sprague-Dawley , Tetraciclinas/uso terapêutico , Fator de Necrose Tumoral alfa/análise
15.
J Periodontal Res ; 37(1): 1-7, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11842933

RESUMO

Periodontal disease is characterized by excessive host collagenase resulting in loss of gingival and periodontal ligament collagen and adjacent alveolar bone. Intragingival endotoxin injection induces a model of periodontal disease characterized by rapid bone loss with biochemical features similar to that of naturally occurring adult periodontitis. CH1766, a peptide with a zinc binding moeity which fits into the active site of the enzyme, and CH6631, a hydroxamic acid derivative with aryl-substituted sulphonamide residues, are inhibitors of matrix metalloproteinases (MMPIs) with differing inhibitory profiles as characterized by in vitro assays. In this study, endotoxin was injected into the gingivae of rats which were then treated orally with either 3 mg/kg or 30 mg/kg of one of the two inhibitory compounds. The gingival tissues were assessed for collagenase and gelatinase activity, plus three different pro-inflammatory cytokines. In addition, alveolar bone height in defleshed jaws was studied by computerized morphometric analysis and scanning electron microscopy. Both drugs reduced active and/or total MMP activity, in many cases to normal, and also partially normalized cytokine levels as well. A dose-response effect was seen with regard to amelioration of lipopolysaccharide-induced alveolar bone loss with both drugs. Other than studies with tetracyclines, this is the first report of beneficial effects of MMPIs in a model of periodontal disease, strongly suggesting that this class of agents could bring therapeutic benefit to patients with this disorder, and that periodontal disease can be used as a model to demonstrate in vivo efficacy of this class of drugs.


Assuntos
Perda do Osso Alveolar/prevenção & controle , Inibidores de Metaloproteinases de Matriz , Periodontite/complicações , Inibidores de Proteases/uso terapêutico , Proteínas ADAM , Proteína ADAM17 , Perda do Osso Alveolar/patologia , Processo Alveolar/patologia , Animais , Proteínas de Transporte/administração & dosagem , Proteínas de Transporte/uso terapêutico , Cefalometria , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Endotoxinas/efeitos adversos , Escherichia coli , Gelatinases/antagonistas & inibidores , Gengiva/efeitos dos fármacos , Gengiva/enzimologia , Ácidos Hidroxâmicos/administração & dosagem , Ácidos Hidroxâmicos/uso terapêutico , Interleucina-1/análise , Interleucina-1/antagonistas & inibidores , Interleucina-6/análise , Interleucina-6/antagonistas & inibidores , Lipopolissacarídeos/efeitos adversos , Masculino , Metaloendopeptidases/antagonistas & inibidores , Microscopia Eletrônica de Varredura , Inibidores de Proteases/administração & dosagem , Ratos , Ratos Sprague-Dawley , Sulfonamidas/administração & dosagem , Sulfonamidas/uso terapêutico , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/antagonistas & inibidores
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