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1.
Chem Commun (Camb) ; 60(34): 4581-4584, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38576349

RESUMO

A study of an integrated OPECT biosensor gate and the EC color-changing region on the same chip was carried out, achieving sensitive detection through bioetching-induced signal changes. Enzymatic bioetching enables specific alkaline phosphatase (ALP) detection by catalyzing the production of CdS, which modulates the channel current and generates a visual signal.


Assuntos
Fosfatase Alcalina , Técnicas Biossensoriais , Técnicas Eletroquímicas , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/análise , Transistores Eletrônicos , Compostos de Cádmio/química , Sulfetos/química , Processos Fotoquímicos
2.
Microb Pathog ; 190: 106641, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38588925

RESUMO

This study aimed to investigate the impact of incorporating kefir into the diet on biometric parameters, as well as the immune and antioxidant responses of the carpet shell clam (Ruditapes decussatus) after an experimental infection by Vibrio alginolyticus. Clams were divided into a control group and a treated group. The control group was fed on spirulina (Arthrospira platensis) alone. While, the treated group was fed on spirulina supplemented with 10% dried kefir. After 21 days, clams were immersed in a suspension of V. alginolyticus 5 × 105 CFU mL -1 for 30 min. Seven days after experimental infection, survival was 100% in both groups. The obtained results showed a slight increase in weight and condition index in clams fed with kefir-supplemented diet for 21 days compared to control clams. Regarding antioxidant responses, the treated group showed higher superoxide dismutase activity compared to the control group. However, the malondialdehyde level was lower in the treated clams than in the control. In terms of immune parameters, the treated group showed slightly elevated activities of phenoloxidase, lysozyme and alkaline phosphatase, whereas a decreased lectin activity was observed compared to the control group. The obtained results suggest that kefir enhanced both the antioxidant and immune response of infected clams.


Assuntos
Adjuvantes Imunológicos , Antioxidantes , Bivalves , Kefir , Probióticos , Superóxido Dismutase , Vibrio alginolyticus , Animais , Probióticos/farmacologia , Bivalves/química , Bivalves/microbiologia , Antioxidantes/metabolismo , Kefir/microbiologia , Superóxido Dismutase/metabolismo , Spirulina/química , Malondialdeído/metabolismo , Malondialdeído/análise , Ração Animal , Monofenol Mono-Oxigenase/metabolismo , Suplementos Nutricionais , Fosfatase Alcalina/metabolismo , Muramidase/metabolismo , Vibrioses/prevenção & controle
3.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(2): 172-180, 2024 Apr 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38597077

RESUMO

OBJECTIVES: The effect of TiO2 nanotube morphology on the differentiation potency of senescent periodontal ligament stem cells was investigated. METHODS: Two types of titanium sheets with TiO2 nanotube morphology (20V-NT and 70V-NT) were prepared via anodic oxidation at 20 and 70 V separately, and their surface morphology was observed. Young periodontal ligament stem cells were cultivated in an osteogenic induction medium, and the most effective surface morphology in promoting osteogenic differentiation was selected. RO3306 and Nutlin-3a were used to induce the aging of young periodontal ligament stem cells, and senescent periodontal ligament stem cells were obtained. The osteogenic differentiation of senescent periodontal ligament stem cells was induced, and the effect of surface morphology on osteogenic differentiation was observed. RESULTS: Nanotube morphology was achieved on the surfaces of titanium sheets through anodic oxidation, and the diameters of the nanotubes increased with voltage. A significant difference in the effect of nanotube morphology was found among nanotubes with different diameters in the young periodontal ligament stem cells. The surface nanotube morphology of 20V-NT had a more significant effect that promoted osteogenic differentiation. Compared with a smooth titanium sheet, the surface nanotube morphology of 20V-NT increased the number of alkaline phosphatase-positive senescent periodontal ligament stem cells and promoted calcium deposition and the expression of osteogenic marker genes Runt-related transcription factor 2, osteopontin, and osteocalcin. CONCLUSIONS: A special nanotube morphology enhances the differentiation ability of senescent periodontal ligament stem cells, provides an effective method for periodontal regeneration, and further improves the performance of implants.


Assuntos
Implantes Dentários , Osteogênese , Ligamento Periodontal/metabolismo , Titânio/metabolismo , Titânio/farmacologia , Células-Tronco , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/farmacologia
4.
Korean J Gastroenterol ; 83(4): 163-166, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38659253

RESUMO

Malignant melanoma (MM) is an aggressive tumor that can metastasize to any organ, but biliary tract metastasis is scarce. We describe a very rare case of MM metastasis to the common bile duct (CBD), presented with only dyspeptic symptoms. The patient had mildly elevated alkaline phosphatase and gamma-glutamyl transferase levels. Magnetic resonance cholangiopancreatography demonstrated a dilated common bile duct with a distal stricture. The MM diagnosis was established with the ampulla of Vater biopsy specimens obtained by endoscopic retrograde cholangiopancreatography (ERCP), and the patient's symptoms were resolved after biliary stenting. Both primary CBD cancer and other cancer types like MM that metastasize to CBD can cause obstruction and can be manifested only by dyspeptic symptoms. MM metastasis to CBD can cause obstruction manifested only by dyspeptic symptoms without obstructive jaundice. ERCP can be employed as a promising option for treatment and diagnosis. New-onset dyspeptic symptoms in patients with a history of MM should be investigated thoroughly, especially in the context of biliary metastasis.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Colangiopancreatografia por Ressonância Magnética , Dispepsia , Melanoma , Tomografia Computadorizada por Raios X , Humanos , Melanoma/diagnóstico , Melanoma/secundário , Melanoma/patologia , Melanoma/complicações , Dispepsia/diagnóstico , Dispepsia/etiologia , Masculino , Pessoa de Meia-Idade , Ducto Colédoco/patologia , gama-Glutamiltransferase/sangue , Neoplasias do Ducto Colédoco/diagnóstico , Neoplasias do Ducto Colédoco/patologia , Neoplasias do Ducto Colédoco/complicações , Neoplasias do Ducto Colédoco/secundário , Fosfatase Alcalina/sangue , Fosfatase Alcalina/metabolismo
5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 512-519, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38660860

RESUMO

OBJECTIVE: To explore the effects and mechanisms of chidamide on the osteogenic differentiation of bone marrow mesenchymal stromal cells (MSC) from myelodysplastic syndromes (MDS). METHODS: MSC were isolated and cultured from bone marrow of MDS patients and healthy donors. CCK-8 assay was used to detect the effects of chidamide on the proliferation of MSC. The effects of chidamide on the activity of histone deacetylase (HDAC) in MSC was measured by a fluorescence assay kit and Western blot. Alkaline phosphatase (ALP) activity was detected on day 3 and calcium nodule formation was observed by Alizarin Red staining on day 21 after osteogenic differentiation. The expression of early and late osteogenic genes was detected on day 7 and day 21, respectively. RT-PCR and Western blot were used to detect the effects of chidamide on mRNA and protein expression of RUNX2 which is the key transcription factor during osteogenesis. RESULTS: As the concentration of chidamide increased, the proliferation of MSC was inhibited. However, at a low concentration (1 µmol/L), chidamide had no significant inhibitory effect on MSC proliferation but significantly inhibited HDAC activity. In MSC from both MDS patients and healthy donors, chidamide (1 µmol/L) significantly increased ALP activity, calcium nodule formation, thereby mRNA expression of osteogenic genes, and restored the reduced osteogenic differentiation ability of MDS-MSC compared to normal MSC. Mechanistic studies showed that the osteogenic-promoting effect of chidamide may be related to the upregulation of RUNX2 . CONCLUSION: Chidamide can inhibit HDAC activity in MSC, upregulate the expression of the osteogenic transcription factor RUNX2, and promote the osteogenic differentiation of MDS-MSC.


Assuntos
Aminopiridinas , Diferenciação Celular , Proliferação de Células , Subunidade alfa 1 de Fator de Ligação ao Core , Células-Tronco Mesenquimais , Síndromes Mielodisplásicas , Osteogênese , Humanos , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Aminopiridinas/farmacologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células da Medula Óssea , Benzamidas/farmacologia , Histona Desacetilases/metabolismo , Fosfatase Alcalina/metabolismo
6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 493-498, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38660857

RESUMO

OBJECTIVE: To investigate the relationship between clinical indicators of CRAB symptoms and antioxidant enzyme activity in patients with multiple myeloma (MM). METHODS: The activity of catalase (CAT), glutathione peroxidase (GPX), and superoxide dismutase (SOD) in the bone marrow supernatants of 44 patients with MM and 12 patients with non-malignant hematological diseases was detected by colorimetric assay, and then the differences in the activity of antioxidant enzymes between the two groups were compared. Furthermore, the relationship between the activity of antioxidant enzymes in the MM group and the levels of serum calcium, serum creatinine (Scr), hemoglobin (Hb), alkaline phosphatase (ALP) as well as bone lesions were analyzed. RESULTS: The antioxidant enzyme activity was lower in MM patients compared with the control group (P < 0.05). When the concentrations of serum calcium and ALP were higher than the normal levels, Hb was lower than 85 g/L, and there were multiple bone lesions, the activity of CAT, SOD and GPX was significantly declined (P < 0.05); When the concentration of Scr≥177 µmol/L, the activity of GPX was significantly declined (P < 0.05). Regression analyses showed that CAT, SOD and GPX were negatively correlated with serum calcium (r =-0.538, r =-0.456, r =-0.431), Scr (r =-0.342, r =-0.384, r =-0.463), and ALP (r =-0.551, r =-0.572, r =-0.482). CONCLUSION: The activity of antioxidant enzymes, including CAT, SOD and GPX, were decreased in patients with MM and they were negatively correlated with some clinical indicators of CRAB symptoms (such as serum calcium, Scr, and ALP), which suggests that promoting the activity of antioxidant enzymes may be beneficial to treat the CRAB symptoms of the patients with MM.


Assuntos
Fosfatase Alcalina , Antioxidantes , Cálcio , Catalase , Glutationa Peroxidase , Mieloma Múltiplo , Superóxido Dismutase , Humanos , Glutationa Peroxidase/sangue , Glutationa Peroxidase/metabolismo , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo , Fosfatase Alcalina/sangue , Fosfatase Alcalina/metabolismo , Catalase/sangue , Catalase/metabolismo , Antioxidantes/metabolismo , Cálcio/sangue , Cálcio/metabolismo , Creatinina/sangue , Braquiúros , Medula Óssea
7.
BMC Oral Health ; 24(1): 394, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539149

RESUMO

OBJECTIVE: The objective of this study was to assess the characterization of human acellular amniotic membrane (HAAM) using various decellularization methods and their impact on the proliferation and differentiation of human dental pulp stem cells (DPSCs). The goal was to identify scaffold materials that are better suited for pulp regeneration. METHODS: Six different decellularization methods were used to generate the amniotic membranes. The characteristics of these scaffolds were examined through hematoxylin and eosin (H&E) staining, scanning electron microscopy (SEM), and immunohistofluorescence staining (IHF). The DPSCs were isolated, cultured, and their capacity for multidirectional differentiation was verified. The third generation (P3) DPSCs, were then combined with HAAM to form the decellularized amniotic scaffold-dental pulp stem cell complex (HAAM-DPSCs complex). Subsequently, the osteogenic capacity of the HAAM-DPSCs complex was evaluated using CCK8 assay, live-dead cell staining, alizarin red and alkaline phosphatase staining, and real-time quantitative PCR (RT-PCR). RESULTS: Out of the assessed decellularization methods, the freeze-thaw + DNase method and the use of ionic detergent (CHAPS) showed minimal changes in structure after decellularization, making it the most effective method. The HAAM-DPSCs complexes produced using this method demonstrated enhanced biological properties, as indicated by CCK8, alizarin red, alkaline phosphatase staining, and RT-PCR. CONCLUSION: The HAAM prepared using the freeze-thaw + DNase method and CHAPS methods exhibited improved surface characteristics and significantly enhanced the proliferation and differentiation capacity of DPSCs when applied to them. The findings, therefore demonstrate the capacity for enhanced pulp regeneration therapy.


Assuntos
Âmnio , Antraquinonas , Polpa Dentária , Humanos , Âmnio/metabolismo , Células Cultivadas , Fosfatase Alcalina/metabolismo , Células-Tronco/metabolismo , Regeneração , Osteogênese , Diferenciação Celular , Desoxirribonucleases/metabolismo , Proliferação de Células
8.
BMC Musculoskelet Disord ; 25(1): 206, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454404

RESUMO

BACKGROUND: Osteoporosis is a genetic disease caused by the imbalance between osteoblast-led bone formation and osteoclast-induced bone resorption. However, further gene-related pathogenesis remains to be elucidated. METHODS: The aberrant expressed genes in osteoporosis was identified by analyzing the microarray profile GSE100609. Serum samples of patients with osteoporosis and normal group were collected, and the mRNA expression of candidate genes was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The mouse cranial osteoblast MC3T3-E1 cells were treated with dexamethasone (DEX) to mimic osteoporosis in vitro. Alizarin Red staining and alkaline phosphatase (ALP) staining methods were combined to measure matrix mineralization deposition of MC3T3-E1 cells. Meanwhile, the expression of osteogenesis related genes including alkaline phosphatase (ALP), osteocalcin (OCN), osteopontin (OPN), Osterix, and bone morphogenetic protein 2 (BMP2) were evaluated by qRT-PCR and western blotting methods. Then the effects of candidate genes on regulating impede bone loss caused by ovariectomy (OVX) in mice were studied. RESULTS: Cyclin A1 (CCNA1) was found to be significantly upregulated in serum of osteoporosis patients and the osteoporosis model cells, which was in line with the bioinformatic analysis. The osteogenic differentiation ability of MC3T3-E1 cells was inhibited by DEX treatment, which was manifested by decreased Alizarin Red staining intensity, ALP staining intensity, and expression levels of ALP, OCN, OPN, Osterix, and BMP2. The effects of CCNA1 inhibition on regulating osteogenesis were opposite to that of DEX. Then, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis demonstrated that genes negatively associated with CCNA1 were enriched in the TGF-beta signaling pathway. Inhibitor of TGF-beta signaling pathway partly reversed osteogenesis induced by suppressed CCNA1. Furthermore, suppressed CCNA1 relieved bone mass of OVX mice in vivo. CONCLUSION: Downregulation of CCNA1 could activate TGF-beta signaling pathway and promote bone formation, thus playing a role in treatment of osteoporosis.


Assuntos
Antraquinonas , Osteoporose , Fator de Crescimento Transformador beta , Animais , Feminino , Humanos , Camundongos , Fosfatase Alcalina/metabolismo , Diferenciação Celular , Ciclina A1/metabolismo , Osteoblastos/metabolismo , Osteogênese , Osteoporose/induzido quimicamente , Fator de Crescimento Transformador beta/metabolismo , Fatores de Crescimento Transformadores/efeitos adversos , Fatores de Crescimento Transformadores/metabolismo
9.
Protein Expr Purif ; 218: 106446, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38395209

RESUMO

The small GTPase Rat sarcoma virus proteins (RAS) are key regulators of cell growth and involved in 20-30% of cancers. RAS switches between its active state and inactive state via exchange of GTP (active) and GDP (inactive). Therefore, to study active protein, it needs to undergo nucleotide exchange to a non-hydrolysable GTP analog. Calf intestine alkaline phosphatase bound to agarose beads (CIP-agarose) is regularly used in a nucleotide exchange protocol to replace GDP with a non-hydrolysable analog. Due to pandemic supply problems and product shortages, we found the need for an alternative to this commercially available product. Here we describe how we generated a bacterial alkaline phosphatase (BAP) with an affinity tag bound to an agarose bead. This BAP completely exchanges the nucleotide in our samples, thereby demonstrating an alternative to the commercially available product using generally available laboratory equipment.


Assuntos
Proteínas Monoméricas de Ligação ao GTP , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Nucleotídeos , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Sefarose , Guanosina Trifosfato/metabolismo , Guanosina Difosfato/metabolismo
10.
Bone ; 181: 117033, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38307176

RESUMO

Alkaline phosphatase (ALP) is detected in most human tissues. However, ALP activity is routinely assayed using high concentrations of artificial colorimetric substrates in phosphate-free laboratory buffers at lethal pH. Hypophosphatasia (HPP) is the inborn-error-of-metabolism caused by loss-of-function mutation(s) of the ALPL gene that encodes the ALP isoenzyme expressed in bone, liver, kidney, and elsewhere and is therefore designated "tissue-nonspecific" ALP (TNSALP). Consequently, HPP harbors clues concerning the biological function of this phosphohydrolase that is anchored onto the surface of cells. The biochemical signature of HPP features low serum ALP activity (hypophosphatasemia) together with elevated plasma levels of three natural substrates of TNSALP: i) phosphoethanolamine (PEA), a component of the linkage apparatus that binds ALPs and other proteins to the plasma membrane surface; ii) inorganic pyrophosphate (PPi), an inhibitor of bone and tooth mineralization; and iii) pyridoxal 5'-phosphate (PLP), the principal circulating vitameric form of vitamin B6 (B6). Autosomal dominant and autosomal recessive inheritance involving several hundred ALPL mutations underlies the remarkably broad-ranging expressivity of HPP featuring tooth loss often with muscle weakness and rickets or osteomalacia. Thus, HPP associates the "bone" isoform of TNSALP with biomineralization, whereas the physiological role of the "liver", "kidney", and other isoforms of TNSALP remains uncertain. Herein, to examine HPP's broad-ranging severity and the function of TNSALP, we administered an oral challenge of pyridoxine (PN) hydrochloride to 116 children with HPP. We assayed both pre- and post-challenge serum ALP activity and plasma levels of PLP, the B6 degradation product pyridoxic acid (PA), and the B6 vitamer pyridoxal (PL) that can enter cells. Responses were validated by PN challenge of 14 healthy adults and 19 children with metabolic bone diseases other than HPP. HPP severity was assessed using our HPP clinical nosology and patient height Z-scores. PN challenge of all study groups did not alter serum ALP activity in our clinical laboratory. In HPP, both the post-challenge PLP level and the PLP increment correlated (Ps < 0.0001) with the clinical nosology and height Z-scores (Rs = +0.6009 and + 0.4886, and Rs = -0.4846 and - 0.5002, respectively). In contrast, the plasma levels and increments of PA and PL from the PN challenge became less pronounced with HPP severity. We discuss how our findings suggest extraskeletal TNSALP primarily conditioned the PN challenge responses, and explain why they caution against overzealous B6 supplementation of HPP.


Assuntos
Hipofosfatasia , Adulto , Humanos , Criança , Hipofosfatasia/genética , Fosfatase Alcalina/metabolismo , Piridoxina , Vitamina B 6 , Piridoxal , Vitaminas
11.
Food Chem ; 443: 138569, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38306906

RESUMO

Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin and seriously threatens food safety, which requires rapid and sensitive detection methods for monitoring ZEN in agro-products. Herein, an alkaline phosphatase-tagged single-chain variable fragment fusion protein (ALP-scFv) was used as a bifunctional tracer to develop a colorimetric enzyme immunoassay (CEIA) and a chemiluminescent enzyme immunoassay (CLEIA) for ZEN. In addition, the interactions between scFv and ZEN were exploited by computer-assisted simulation, and four key amino acid sites were preliminarily identified. After optimization, the CEIA and CLEIA exhibited a limit of detection of 0.02 and 0.006 ng/mL, respectively. Furthermore, both methods showed favorable accuracy in recovery experiments and good selectivity in cross reactions. Moreover, the detection results of the actual samples from both methods correlated well with those from high-performance liquid chromatography. Overall, the ALP-scFv fusion tracer-based CEIA and CLEIA are demonstrated as reliable tools for ZEN detection in food.


Assuntos
Anticorpos de Cadeia Única , Zearalenona , Fosfatase Alcalina/metabolismo , Zearalenona/análise , Colorimetria , Técnicas Imunoenzimáticas , Corantes/análise , Contaminação de Alimentos/análise , Imunoensaio/métodos
12.
J Biomater Sci Polym Ed ; 35(6): 880-897, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38346177

RESUMO

The aim of the in vitro study was to asses the effect of hyaluronate in conjunction with bovine derived xenografts on the viability, proliferation on day 4, 7 and 10, expression of early osteogenic differentiation marker Alkaline phosphatase on day 14 and 21, collagen, calcium deposition on day 14, 21 and 28 and cellular characteristics, as assessed through live cell image analysis, confocal laser scanning microscopy and scanning electron microscopy, in primary human osteoblasts compared to three bovine xenografts without hyaluronate. All experiments were performed in triplicates. Data were compared between groups and timepoints using one-way analysis of variance (ANOVA). Bonferroni post hoc test were further used for multiple comparison between groups (p < .05) An increase in cell viability (p < .05) and enhanced ALP activity was observed in all xenografts. Specimens containing hyaluronate showed a highest significant difference (23755 ± 29953, p < .0001). The highest levels of calcium (1.60 ± 0.30) and collagen (1.92 ± 0.09, p < .0001) deposition were also observed with hyaluronate loaded groups. The osteoblasts were well attached and spread on all xenograft groups. However, a higher number of cells were observed with hyaluronate functionalized xenograft (76.27 ± 15.11, (p < .0001) in live cell image analysis and they migrated towards the graft boundaries. The biofunctionalization of xenografts with hyaluronate improves their in vitro performance on human osteoblasts. This suggests that hyaluronate might be able to improve the bone regeneration when using such xenografts.


Assuntos
Cálcio , Osteogênese , Humanos , Animais , Bovinos , Osteogênese/fisiologia , Xenoenxertos , Cálcio/metabolismo , Diferenciação Celular , Osteoblastos , Colágeno/farmacologia , Glicosaminoglicanos , Proliferação de Células , Fosfatase Alcalina/metabolismo
13.
Org Biomol Chem ; 22(8): 1714-1720, 2024 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-38318943

RESUMO

Ratiometric fluorescent assays have a built-in correction factor which enhances assay accuracy and reliability. We have developed fluorescent ratiometric supramolecular tandem assays for phosphatase and phytase enzymes using a mixture of three molecular components. One of the molecules is a tetra-cationic fluorescence quencher called CalixPyr which can bind and quench the polyanionic pyrene fluorophore, CMP, that emits at 430 nm. Polyphosphates can disrupt the CMP/CalixPyr complex and alter the fluorescence intensity (responsive signal). CalixPyr has no effect on the fluorescence emission of cationic pentamethine cyanine fluorophore, cCy5, which emits at 665 nm and acts as a non-responsive reference signal. The continuous ratiometric fluorescent assay for alkaline phosphatase monitored hydrolytic consumption of adenosine triphosphate (ATP). The continuous ratiometric fluorescent assay for phytase activity monitored hydrolytic consumption of phytate. With further development this latter assay may be useful for high throughput assessment of phytase activity in individual batches of fortified animal feed. It is likely that the three-molecule mixture (CMP, CalixPyr, cCy5) can become a general assay platform for other enzymes that catalyse addition/removal of phosphate groups from appropriate molecular substrates.


Assuntos
6-Fitase , Monoéster Fosfórico Hidrolases , Animais , 6-Fitase/metabolismo , Reprodutibilidade dos Testes , Fosfatase Alcalina/metabolismo , Hidrólise , Corantes Fluorescentes/química
14.
Braz J Biol ; 83: e272512, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422258

RESUMO

This study aimed to correlate the values of liver markers with oxidative stress markers in patients with multidrug-resistant tuberculosis in the Brazilian Amazon. A total of 30 patients from the Tuberculosis clinic of a referral hospital were admitted to the study. Whole blood samples were collected for analysis of liver enzyme values and oxidative stress markers by spectrophotometry. The prevalence was male (60%) and the 18-29 age group was the most affected. Patients with multidrug-resistant tuberculosis presented catalase values with a median equal to 6.94 U/gHb and for glutathione, the median was equal to 14.76 µg∕ml. As for the values of liver enzymes (AST, ALT, Gamma-GT and Alkaline phosphatase) the patients had medians equal to 60.50 (U/L); 80 (U/L); 54 (U/L); and 100 (U/L) respectively (p<0.0001). The results suggest a hepatotoxic effect of the drug, which recommends further studies with a larger number of samples in order to investigate the predictors of liver damage in patients with multidrug-resistant tuberculosis.


Assuntos
Fígado , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Masculino , Brasil , Estresse Oxidativo , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/metabolismo
15.
Biomater Sci ; 12(5): 1274-1280, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38251092

RESUMO

Herein, we show a pair of leucine-rich L- and D-phosphopeptides which self-assemble into twisting nanofibers, whose secondary structures contain a strong ß-sheet component after being dephosphorylated by alkaline phosphatase (ALP). While being incubated with ALP overexpressing osteosarcoma cells, both of the peptides self-assemble in the nuclei and induce cell death. The cell death involves multiple cell death modalities and occurs along with the disruption of cell membranes. Enzyme-instructed self-assembly (EISA) inhibits osteosarcoma cells and shows no side effect to other cells. In addition, the cancer cells hardly gain drug resistance after repeated treatment. This work reports a pair of EISA-based nanofibers to target cell nuclei, and also provides a novel chemotherapeutic agent to inhibit osteosarcoma cells without side effects and drug resistance.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Leucina , Peptídeos/farmacologia , Peptídeos/química , Osteossarcoma/tratamento farmacológico , Morte Celular , Fosfatase Alcalina/metabolismo , Neoplasias Ósseas/tratamento farmacológico
16.
Biomacromolecules ; 25(2): 1310-1318, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38265878

RESUMO

Although the formation of peptide assemblies catalyzed by alkaline phosphatase (ALP) has received increasing attention in inhibiting cancer cells, the detailed enzyme kinetics of the dephosphorylation of the corresponding phosphopeptide assemblies have yet to be determined. We recently discovered that assemblies from a phosphopentapeptide can form intracellular nanoribbons that kill induced pluripotent stem cells or osteosarcoma cells, but the kinetics of enzymatic dephosphorylation remain unknown. Thus, we chose to examine the enzyme kinetics of the dephosphorylation of the phosphopentapeptide [NBD-LLLLpY (1)] from concentrations below to above its critical micelle concentration (CMC). Our results show that the phosphopeptide exhibits a CMC of 75 µM in phosphate saline buffer, and the apparent Vmax and Km values of alkaline phosphatase catalyzed dephosphorylation are approximately 0.24 µM/s and 5.67 mM, respectively. Despite dephosphorylation remaining incomplete at 60 min in all the concentrations tested, dephosphorylation of the phosphopeptide at concentrations of 200 µM or above mainly results in nanoribbons, dephosphorylation at concentrations of CMC largely produces nanofibers, and dephosphorylation below the CMC largely generates nanoparticles. Moreover, the formation of nanoribbons correlates with the intranuclear accumulation of the pentapeptide. By providing the first examination of the enzymatic kinetics of phosphopeptide assemblies, this work further supports the notion that the assemblies of phosphopentapeptides can act as a new functional entity for controlling cell fates.


Assuntos
Nanotubos de Carbono , Fosfopeptídeos , Fosfatase Alcalina/metabolismo , Cinética
17.
Chem Asian J ; 19(1): e202300878, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37934144

RESUMO

As biological enzymes regulate metabolic processes, alkaline phosphatase (ALP) is a critical diagnostic indicator associated with many diseases. To accurately measure the enzyme activity, nanozymactic materials can offer sensitive strategies for ALP detection. However, nanozymes often lack specific target binding sites, and the presence of common co-components, e. g., metal ions, may cause false-positive or false-negative results in enzyme activity determination. Herein, we developed a colorimetric assay for ALP detection using metal-free nanozymatic carbon dots (CDs). The ALP hydrolysis of pyrophosphate ions (PPi) to phosphate ions (Pi) induces a "turn-on" response based on the nanozyme activity. This PPi-induced inhibition mechanism is extensively studied via the Michaelis-Menten model, revealing that PPi acts as a noncompetitive inhibitor for CDs at a binding site distinct from the common nanozyme active site. With superior responses to ALP substrates, a highly sensitive and selective method is established for sensing ALP activity with a linear range of 0.010-0.200 U/L and a detection limit of 0.009 U/L. This finding explores the recognition and binding behavior of nanozymes, allowing for precise and reliable measurements even in complex samples, and represents a significant breakthrough for nanozyme-based assays in biological analysis.


Assuntos
Fosfatase Alcalina , Carbono , Fosfatase Alcalina/metabolismo , Carbono/química , Domínio Catalítico , Hidrólise , Metais , Corantes , Íons , Limite de Detecção , Colorimetria
18.
J Am Coll Surg ; 238(1): 70-80, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37870235

RESUMO

BACKGROUND: Intestinal homeostasis is a crucial factor for complication-free short- and long-term postoperative recovery. The brush border enzyme intestinal alkaline phosphatase (IAP) is an important regulator of gut barrier function and intestinal homeostasis and prevents endotoxemia by detoxifying lipopolysaccharides (LPSs). As IAP is predominantly secreted by enterocytes in the duodenum, we hypothesized that pancreaticoduodenectomy (PD) leads to a significantly stronger decrease in IAP than other major abdominal surgery. STUDY DESIGN: Pre- and postoperative blood, stool, and intestinal samples were collected from patients undergoing PD, as well as other major surgical procedures without duodenectomy. The samples were analyzed using enzyme histochemistry, the para -nitrophenyl phosphate method for IAP, and the limulus amebocyte lysate assay for LPS. RESULTS: Overall, 88 patients were prospectively enrolled in the study. Fecal IAP activity negatively correlated with serum LPS (r = -0.3603, p = 0.0006). PD led to a significant decline in IAP compared to preoperative baseline levels (p < 0.0001). The decline in IAP correlated with the length of proximal small intestinal resection (r = 0.4271, p = 0.0034). Compared to controls, PD was associated with a much more pronounced reduction in IAP-also after adjusting for surgical trauma (operative time, blood loss; r = 0.4598, p = 0.0086). Simultaneously, PD triggered a clearly more prominent increase in serum LPS compared to controls (p = 0.0001). Increased postoperative LPS was associated with an elongated hospitalization (r = 0.7534, p = 0.0062) and more prominent in pancreatic cancer (p = 0.0009). CONCLUSIONS: Based upon the functional roles for IAP, supplementation with exogenous IAP might be a new treatment option to improve short- and long-term outcome after PD.


Assuntos
Fosfatase Alcalina , Lipopolissacarídeos , Pancreaticoduodenectomia , Humanos , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/fisiologia , Homeostase , Mucosa Intestinal , Período Pós-Operatório , Pancreaticoduodenectomia/efeitos adversos , Pancreaticoduodenectomia/reabilitação
19.
J Microbiol Biotechnol ; 34(2): 415-424, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38044675

RESUMO

This study reveals that low-molecular-weight collagen peptide (LMWCP) can stimulate the differentiation and the mineralization of MC3T3-E1 cells in vitro and attenuate the bone remodeling process in ovariectomized (OVX) Sprague-Dawley rats in vivo. Moreover, the assessed LMWCP increased the activity of alkaline phosphatase (ALP), synthesis of collagen, and mineralization in MC3T3-E1 cells. Additionally, mRNA levels of bone metabolism-related factors such as the collagen type I alpha 1 chain, osteocalcin (OCN), osterix, bone sialoprotein, and the Runt family-associated transcription factor 2 were increased in cells treated with 1,000 µg/ml of LMWCP. Furthermore, we demonstrated that critical bone morphometric parameters exhibited significant differences between the LMWCP (400 mg/kg)-receiving and vehicle-treated rat groups. Moreover, the expression of type I collagen and the activity of ALP were found to be higher in both the femur and lumbar vertebrae of OVX rats treated with LMWCP. Finally, the administration of LMWCP managed to alleviate osteogenic parameters such as the ALP activity and the levels of the bone alkaline phosphatase, the OCN, and the procollagen type 1 N-terminal propeptide in OVX rats. Thus, our findings suggest that LMWCP is a promising candidate for the development of food-based prevention strategies against osteoporosis.


Assuntos
Fosfatase Alcalina , Osteoblastos , Ratos , Animais , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/farmacologia , Ratos Sprague-Dawley , Colágeno/metabolismo , Peptídeos/farmacologia , Osteogênese , Osteocalcina/genética , Osteocalcina/metabolismo , Osteocalcina/farmacologia , Diferenciação Celular
20.
Artigo em Inglês | MEDLINE | ID: mdl-38052346

RESUMO

Postprandial kinetics of genes expression of gastric (chitinase, pepsinogen) and intestinal (alkaline phosphatase, maltase) digestive enzymes and nutrient transporters (peptide transporter 1, sodium-glucose transporter 1), Brush Border Membrane (BBM) enzymes activity (alkaline phosphatase, leucine aminopeptidase, maltase, saccharase) and blood biochemistry (triglycerides, cholesterol, protein, albumin, glucose, amino acids) through NMR spectroscopy, were investigated in rainbow trout (Oncorhynchus mykiss) fed a commercial aquafeed. For this purpose, fish were starved 72 h and digestive tract and blood were sampled before the meal and at 1.5, 3, 6, 9, 12, and 24 h after feeding (T0, T1.5, T3, T6, T9, T12 and T24). The postprandial kinetic showed that the expression of the genes involved in digestion and nutrient transport, the activity of BBM enzymes, and the presence of metabolites in blood were stimulated in different ways by the presence of feed in the digestive tract. The expression of most genes peaked 3 h after meal except gastric pepsinogen and maltase in distal intestine that peaked at T9 and T12, respectively. The activity of BBM enzymes were stimulated differently based on the intestine tract. The plasma proteins level increased from T1.5 until T9, while the other blood parameters unvariated during the postprandial period. This study supplied useful information about the physiological effects a single meal as a potential tool for planning nutritional studies involving the digestive functions.


Assuntos
Oncorhynchus mykiss , Animais , Oncorhynchus mykiss/fisiologia , alfa-Glucosidases/metabolismo , Período Pós-Prandial/fisiologia , Fosfatase Alcalina/metabolismo , Pepsinogênios/metabolismo
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