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1.
Curr Issues Mol Biol ; 44(9): 3980-4000, 2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36135185

RESUMEN

Polyphenols and flavonoids from non-fermented green tea and fully-fermented black tea exhibit antioxidant abilities that function as natural health foods for daily consumption. Nonetheless, evidence regarding prophylactic effects of purple shoot tea on immunomodulation remains scarce. We compared the immunomodulatory effects of different tea processes on oxidative stress and cytokine expressions in lipopolysaccharide (LPS)-stimulated macrophages. Major constituents of four tea products, Taiwan Tea Experiment Station No.12 (TTES No. 12) black and green tea and purple shoot black and purple shoot green tea (TB, TG, PB and PG, respectively), were analyzed to explore the prophylactic effects on expressions of free radicals, nitric oxide (NO), monocyte chemoattractant protein-1 (MCP-1), interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) in LPS-activated RAW264.7 cell models. PG contained abundant levels of total polyphenols, flavonoids, condensed tannins and proanthocyanidins (371.28 ± 3.83; 86.37 ± 1.46; 234.67 ± 10.1; and 24.81 ± 0.75 mg/g, respectively) contributing to excellent free radical scavenging potency. In both the LPS-activated inflammation model and the prophylactic model, all tea extracts suppressed NO secretion in a dose-dependent manner, especially for PG. Intriguingly, most tea extracts enhanced expressions of IL-6 in LPS-stimulated macrophages, except PG. However, all teas disrupted downstream transduction of chemoattractant MCP-1 for immune cell trafficking. In the prophylactic model, all teas inhibited inflammatory responses by attenuating expressions of IL-6 and TNF-α in a dose-dependent manner, especially for TG and PG. Our prophylactic model demonstrated PG exerts robust effects on modulating LPS-induced cytokine expressions of MCP-1, IL-6 and TNF-α through scavenging free radicals and NO. In light of the prophylactic effects on LPS-related inflammation, PG effectively scavenges free radicals to modulate cytokine cascades that could serve as a functional beverage for immunomodulation.

2.
FASEB J ; 35(8): e21785, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34314075

RESUMEN

In the present study, acute onset of severe lupus nephritis was successfully treated in mice using a new, benzamide-linked, small molecule that targets immune modulation and the NLRP3 inflammasome. Specifically, 6-(2,4-difluorophenyl)-3-(3-(trifluoromethyl)phenyl)-2H-benzo[e][1,3]oxazine-2,4(3H)-dione (Cf-02) (a) reduced serum levels of IgG anti-dsDNA, IL-1ß, IL-6, and TNF-α, (b) inhibited activation of dendritic cells and differentially regulated T cell functions, and (c) suppressed the NF-κB/NLRP3 inflammasome axis, targeting priming and activating signals of the inflammasome. Moreover, treatment with Cf-02 significantly inhibited secretion of IL-1ß in lipopolysaccharide-stimulated macrophages, but this effect was abolished by autophagy induction. These results recommend Cf-02 as a promising drug candidate for the serious renal conditions associated with systemic lupus erythematosus. Future investigations should examine whether Cf-02 may also be therapeutic in other types of chronic kidney disease involving NLRP3 inflammasome-driven signaling.


Asunto(s)
Autofagia/efectos de los fármacos , Factores Inmunológicos/farmacología , Interleucina-1beta/inmunología , Nefritis Lúpica/tratamiento farmacológico , FN-kappa B/inmunología , Proteína con Dominio Pirina 3 de la Familia NLR/inmunología , Animales , Estudios de Casos y Controles , Células Cultivadas , Células Dendríticas , Femenino , Humanos , Macrófagos , Ratones , Ratones Endogámicos C57BL , Síndrome de Sjögren
3.
J Pathol ; 253(4): 427-441, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33373038

RESUMEN

IgA nephropathy (IgAN), an immune complex-mediated process and the most common primary glomerulonephritis, can progress to end-stage renal disease in up to 40% of patients. Accordingly, a therapeutic strategy targeting a specific molecular pathway is urgently warranted. Aided by structure characterisation and target identification, we predicted that a novel ring-fused 6-(2,4-difluorophenyl)-3-(3-(trifluoromethyl)phenyl)-2H-benzo[e][1,3]oxazine-2,4(3H)-dione (LCC18) targets the NLRP3 inflammasome, which participates in IgAN pathogenesis. We further developed biomarkers for the disease. We used two complementary IgAN models in C57BL/6 mice, involving TEPC-15 hybridoma-derived IgA, and in gddY mice. Moreover, we created specific cell models to validate therapeutic effects of LCC18 on IgAN and to explain its underlying mechanisms. IgAN mice benefited significantly from treatment with LCC18, showing dramatically improved renal function, including greatly reduced proteinuria and renal pathology. Mechanistic studies showed that the mode of action specifically involved: (1) blocking of the MAPKs/COX-2 axis-mediated priming of the NLRP3 inflammasome; (2) inhibition of ASC oligomerisation and NLRP3 inflammasome assembly by inhibiting NLRP3 binding to PKR, NEK7 and ASC; and (3) activation of autophagy. LCC18 exerts therapeutic effects on murine IgAN by differentially regulating NLRP3 inflammasome activation and autophagy induction, suggesting this new compound as a promising drug candidate to treat IgAN. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Benzamidas/farmacología , Glomerulonefritis por IGA/patología , Factores Inmunológicos/farmacología , Inflamasomas/efectos de los fármacos , Animales , Autofagia/efectos de los fármacos , Benzamidas/química , Modelos Animales de Enfermedad , Femenino , Factores Inmunológicos/química , Ratones , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR/efectos de los fármacos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo
4.
J Cell Mol Med ; 24(23): 13609-13622, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33135320

RESUMEN

Tris (dibenzylideneacetone) dipalladium (Tris DBA), a small-molecule palladium complex, can inhibit cell growth and proliferation in pancreatic cancer, lymphocytic leukaemia and multiple myeloma. Given that this compound is particularly active against B-cell malignancies, we have been suggested that it can alleviate immune complexes (ICs)-mediated conditions, especially IgA nephropathy (IgAN). The therapeutic effects of Tris DBA on glomerular cell proliferation and renal inflammation and mechanism of action were examined in a mouse model of IgAN. Treatment of IgAN mice with Tris DBA resulted in markedly improved renal function, albuminuria and renal pathology, including glomerular cell proliferation, neutrophil infiltration, sclerosis and periglomerular inflammation in the renal interstitium, together with (Clin J Am Soc Nephrol. 2011, 6, 1301-1307) reduced mitochondrial ROS generation; (Am J Physiol-Renal Physiol. 2011. 301, F1218-F1230) differentially regulated autophagy and NLRP3 inflammasome; (Clin J Am Soc Nephrol. 2012, 7, 427-436) inhibited phosphorylation of JNK, ERK and p38 MAPK signalling pathways, and priming signal of the NLRP3 inflammasome; and (Free Radic Biol Med. 2013, 61, 285-297) blunted NLRP3 inflammasome activation through SIRT1- and SIRT3-mediated autophagy induction, in renal tissues or cultured macrophages. In conclusion, Tris DBA effectively ameliorated the mouse IgAN model and targeted signalling pathways downstream of ICs-mediated interaction, which is a novel immunomodulatory strategy. Further development of Tris DBA as a therapeutic candidate for IgAN is warranted.


Asunto(s)
Autofagia/efectos de los fármacos , Glomerulonefritis por IGA/metabolismo , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Compuestos Organometálicos/farmacología , Transducción de Señal/efectos de los fármacos , Sirtuina 1/metabolismo , Sirtuina 3/metabolismo , Animales , Autofagia/genética , Biomarcadores , Biopsia , Modelos Animales de Enfermedad , Glomerulonefritis por IGA/diagnóstico , Glomerulonefritis por IGA/tratamiento farmacológico , Glomerulonefritis por IGA/etiología , Inmunohistoquímica , Pruebas de Función Renal , Activación de Macrófagos , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/patología , Modelos Biológicos , Oxidación-Reducción/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Sirtuina 1/genética , Sirtuina 3/genética , Linfocitos T/inmunología , Linfocitos T/metabolismo , Linfocitos T/patología
5.
Int J Mol Sci ; 21(22)2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-33218086

RESUMEN

We have previously demonstrated calcimimetics optimize the balance between osteoclastic bone resorption and osteoblastic mineralization through upregulating Wingless and int-1 (Wnt) signaling pathways in the mouse and cell model. Nonetheless, definitive human data are unavailable concerning therapeutic effects of Cinacalcet on chronic kidney disease and mineral bone disease (CKD-MBD) and osteoclast-osteoblast interaction. We aim to investigate whether Cinacalcet therapy improves bone mineral density (BMD) through optimizing osteocytic homeostasis in a human model. Hemodialysis patients with persistently high intact parathyroid hormone (iPTH) levels > 300 pg/mL for more than 3 months were included and received fixed dose Cinacalcet (25 mg/day, orally) for 6 months. Bone markers presenting osteoclast-osteoblast communication were evaluated at baseline, the 3rd and the 6th month. Eighty percent of study patients were responding to Cinacalcet treatment, capable of improving BMD, T score and Z score (16.4%, 20.7% and 11.1%, respectively). A significant correlation between BMD improvement and iPTH changes was noted (r = -0.26, p < 0.01). Nonetheless, baseline lower iPTH level was associated with better responsiveness to Cinacalcet therapy. Sclerostin, an inhibitor of canonical Wnt/ß-catenin signaling, was decreased from 127.3 ± 102.3 pg/mL to 57.9 ± 33.6 pg/mL. Furthermore, Wnt-10b/Wnt 16 expressions were increased from 12.4 ± 24.2/166.6 ± 73.3 pg/mL to 33.8 ± 2.1/217.3 ± 62.6 pg/mL. Notably, procollagen type I amino-terminal propeptide (PINP), a marker of bone formation and osteoblastic activity, was increased from baseline 0.9 ± 0.4 pg/mL to 91.4 ± 42.3 pg/mL. In contrast, tartrate-resistant acid phosphatase isoform 5b (TRACP-5b), a marker of osteoclast activity, was decreased from baseline 16.5 ± 0.4 mIU/mL to 7.7 ± 2.2 mIU/mL. Moreover, C-reactive protein levels were suppressed from 2.5 ± 0.6 to 0.8 ± 0.5 mg/L, suggesting the systemic inflammatory burden may be benefited after optimizing the parathyroid-bone axis. In conclusion, beyond iPTH suppression, our human model suggests Cinacalcet intensifies BMD through inhibiting sclerostin expression and upregulating Wnt-10b/Wnt 16 signaling that activates osteoblastic bone formation and inhibits osteoclastic bone resorption and inflammation. From the perspective of translation to humans, this research trial brings a meaningful insight into the osteoblast-osteoclast homeostasis in Cinacalcet therapy for CKD-MBD.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Enfermedades Óseas/terapia , Cinacalcet/uso terapéutico , Osteoblastos/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Insuficiencia Renal Crónica/terapia , Adulto , Anciano , Biomarcadores/metabolismo , Enfermedades Óseas/metabolismo , Resorción Ósea/metabolismo , Calcimiméticos/administración & dosificación , Calcimiméticos/uso terapéutico , Cinacalcet/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoblastos/citología , Osteoblastos/metabolismo , Osteoclastos/citología , Osteoclastos/metabolismo , Osteogénesis/efectos de los fármacos , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Hormona Paratiroidea/metabolismo , Diálisis Renal/métodos , Insuficiencia Renal Crónica/metabolismo , Fosfatasa Ácida Tartratorresistente/metabolismo
6.
J Cell Physiol ; 234(4): 4081-4094, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30370562

RESUMEN

Dysregulation of NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasome is involved in many chronic inflammatory diseases, including gouty arthritis. Activation of the NLRP3 inflammasome requires priming and activation signals: the priming signal controls the expression of NLRP3 and interleukin (IL)-1ß precursor (proIL-1ß), while the activation signal leads to the assembly of the NLRP3 inflammasome and to caspase-1 activation. Here, we reported the effects of the alcoholic extract of Taiwanese green propolis (TGP) on the NLRP3 inflammasome in vitro and in vivo. TGP inhibited proIL-1ß expression by reducing nuclear factor kappa B activation and reactive oxygen species (ROS) production in lipopolysaccharide-activated macrophages. Additionally, TGP also suppressed the activation signal by reducing mitochondrial damage, ROS production, lysosomal rupture, c-Jun N-terminal kinases 1/2 phosphorylation and apoptosis-associated speck-like protein oligomerization. Furthermore, we found that TGP inhibited the NLRP3 inflammasome partially via autophagy induction. In the in vivo mouse model of uric acid crystal-induced peritonitis, TGP attenuated the peritoneal recruitment of neutrophils, and the levels of IL-1ß, active caspase-1, IL-6 and monocyte chemoattractant protein-1 in lavage fluids. As a proof of principle, in this study, we purified a known compound, propolin G, from TGP and identified this compound as a potential inhibitor of the NLRP3 inflammasome. Our results indicated that TGP might be useful for ameliorating gouty inflammation via inhibition of the NLRP3 inflammasome.


Asunto(s)
Antiinflamatorios/farmacología , Artritis Gotosa/prevención & control , Macrófagos/efectos de los fármacos , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Peritonitis/prevención & control , Própolis/farmacología , Animales , Artritis Gotosa/inmunología , Artritis Gotosa/metabolismo , Autofagia/efectos de los fármacos , Citocinas/metabolismo , Modelos Animales de Enfermedad , Humanos , Mediadores de Inflamación/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Estrés Oxidativo/efectos de los fármacos , Peritonitis/inmunología , Peritonitis/metabolismo , Transducción de Señal , Células THP-1
7.
Int J Mol Sci ; 20(18)2019 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-31500176

RESUMEN

Obesity is associated with metabolic endotoxemia, reactive oxygen species (ROS), chronic inflammation, and obese kidney fibrosis. Although the fat-intestine-kidney axis has been documented, the pathomechanism and therapeutic targets of obese kidney fibrosis remain unelucidated. To mimic obese humans with metabolic endotoxemia, high-fat-diet-fed mice (HF group) were injected with lipopolysaccharide (LPS) to yield the obese kidney fibrosis-metabolic endotoxemia mouse model (HL group). Therapeutic effects of ROS, cytosolic phospholipases A2 (cPLA2) and cyclooxygenase-2 (COX-2) inhibitors were analyzed with a quantitative comparison of immunohistochemistry stains and morphometric approach in the tubulointerstitium of different groups. Compared with basal and HF groups, the HL group exhibited the most prominent obese kidney fibrosis, tubular epithelial lipid vacuoles, and lymphocyte infiltration in the tubulointerstitium. Furthermore, inhibitors of nonspecific ROS, cPLA2 and COX-2 ameliorated the above renal damages. Notably, the ROS-inhibitor-treated group ameliorated not only oxidative injury but also the expression of cPLA2 and COX-2, indicating that ROS functions as the upstream signaling molecule in the inflammatory cascade of obese kidney fibrosis. ROS acts as a key messenger in the signaling transduction of obese kidney fibrosis, activating downstream cPLA2 and COX-2. The given antioxidant treatment ameliorates obese kidney fibrosis resulting from a combined high-fat diet and LPS-ROS could serve as a potential therapeutic target of obese kidney fibrosis with metabolic endotoxemia.


Asunto(s)
Ciclooxigenasa 2/genética , Endotoxemia/complicaciones , Enfermedades Renales/etiología , Enfermedades Renales/metabolismo , Obesidad/complicaciones , Fosfolipasas A2 Citosólicas/genética , Especies Reactivas de Oxígeno/metabolismo , Animales , Biomarcadores , Ciclooxigenasa 2/metabolismo , Modelos Animales de Enfermedad , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Fibrosis , Regulación de la Expresión Génica/efectos de los fármacos , Inmunohistoquímica , Enfermedades Renales/tratamiento farmacológico , Enfermedades Renales/patología , Metabolismo de los Lípidos , Linfocitos/inmunología , Linfocitos/metabolismo , Ratones , Terapia Molecular Dirigida , Estrés Oxidativo , Fosfolipasas A2 Citosólicas/metabolismo , Transducción de Señal/efectos de los fármacos
8.
J Am Soc Nephrol ; 28(7): 2022-2037, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28179433

RESUMEN

IL-36 cytokines are proinflammatory and have an important role in innate and adaptive immunity, but the role of IL-36 signaling in renal tubulointerstitial lesions (TILs), a major prognostic feature of renal inflammation and fibrosis, remains undetermined. In this study, increased IL-36α expression detected in renal biopsy specimens and urine samples from patients with renal TILs correlated with renal function impairment. We confirmed the increased expression of IL-36α in the renal tubular epithelial cells of a mouse model of unilateral ureteral obstruction (UUO) and related cell models using mechanically induced pressure, oxidative stress, or high mobility group box 1. In contrast, the kidneys of IL-36 receptor (IL-36R) knockout mice exhibit attenuated TILs after UUO. Compared with UUO-treated wild-type mice, UUO-treated IL-36 knockout mice exhibited markedly reduced NLRP3 inflammasome activation and macrophage/T cell infiltration in the kidney and T cell activation in the renal draining lymph nodes. In vitro, recombinant IL-36α facilitated NLRP3 inflammasome activation in renal tubular epithelial cells, macrophages, and dendritic cells and enhanced dendritic cell-induced T cell proliferation and Th17 differentiation. Furthermore, deficiency of IL-23, which was diminished in IL-36R knockout UUO mice, also reduced renal TIL formation in UUO mice. In wild-type mice, administration of an IL-36R antagonist after UUO reproduced the results obtained in UUO-treated IL-36R knockout mice. We propose that IL-36 signaling contributes to the pathogenesis of renal TILs through the activation of the NLRP3 inflammasome and IL-23/IL-17 axis.


Asunto(s)
Inflamasomas/fisiología , Interleucina-17/fisiología , Interleucina-1/fisiología , Interleucina-23/fisiología , Riñón/patología , Proteína con Dominio Pirina 3 de la Familia NLR/fisiología , Nefritis/etiología , Transducción de Señal , Animales , Fibrosis/etiología , Humanos , Ratones , Obstrucción Ureteral/etiología
9.
Heliyon ; 9(5): e16004, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37206019

RESUMEN

WNT inhibitory factor 1 (WIF1) is known to function as a tumor suppressor gene; it inhibits oncogene activation by preventing WNT signaling. This study investigated the epigenetic regulation of WIF1 gene in bladder cancer. We observed a positive relationship between WIF1 mRNA expression and survival probability of bladder cancer patients. The WIF1 gene expression could be enhanced by DNA demethylation drug 5-aza-2'-deoxycytidine (5-aza-dC) and histone deacetylase inhibitor trichostatin A (TSA), suggesting that epigenetic modifications could regulate WIF1 gene expression. Overexpression of WIF1 inhibited cell proliferation and migration in 5637 cells, confirming the tumor suppressor role of WIF1. 5-Aza-dC dose dependently increased WIF1 gene expression while reducing DNA methylation level, suggesting that reversing WIF1 DNA methylation could activate its gene expression. We collected the cancer tissues and urine pellets of bladder cancer patients and only urine pellets from non-bladder cancer volunteers for DNA methylation analysis, but the methylation level of WIF1 gene -184 to +29 did not differ between patients and controls. We also analyzed glutathione S-transferase Mu 5 (GSTM5) gene methylation level because GSTM5 DNA hypermethylation was suggested to be a tumor biomarker in our previous study. It confirmed a higher GSTM5 DNA methylation in bladder cancer patients than in controls. In summary, this study suggests that the 5-aza-dC activated WIF1 gene which showed an anti-cancer effect, while WIF1 promoter -184 to +29 did not provide a suitable methylation assay region in clinical samples. In contrast, GSTM5 promoter -258 to -89 is a useful region for DNA methylation assay because it shows a higher methylation level in bladder cancer patients.

10.
Foods ; 12(22)2023 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-38002159

RESUMEN

Emerging evidence has demonstrated that using a new manufacturing technology to produce γ-aminobutyric acid (GABA)-fortified oolong (GO) tea could relieve human stress and exert versatile physiological benefits. The purpose of this human study was to investigate the therapeutic effects of daily GO tea consumption on improvements in blood pressure, relaxation-related brain waves, and quality of life (QOL) over a period of 28 consecutive days. Total polyphenols, major catechins, and free amino acids were analyzed via an HPLC assay. Changes in heart rate, blood pressure, α brain waves (index of relaxation), and the eight-item QOL score were investigated on days 0, 7, 14, 21, and 28. The chemical analysis results showed that GO tea contained the most abundant amino acids and GABA, contributing to the relaxation activity. Among all study participants, the daily consumption of GO tea could reduce systolic blood pressure on day 21 and diastolic blood pressure on day 28 (p < 0.05 for both). For participants with pre-hypertension, GO tea could effectively reduce heart rate and systolic and diastolic blood pressure on day 28 (p < 0.05). At the end of the study, incremental changes in alpha brain waves and QOL scores were also demonstrated (p < 0.05 for both). This study suggests that GO tea might potentially serve as a natural source for alternative therapy to improve blood pressure, stress relief, and QOL.

11.
Life (Basel) ; 12(5)2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35629435

RESUMEN

We formerly proved that uremic vascular calcification (UVC) correlates tightly with oxidative elastic lamina (EL) injury and two cell fates (apoptosis and osteocytic conversion) in smooth muscle cells (SMC) of chronic kidney disease (CKD) patients and eliminating p-cresyl sulfate (PCS)-activated intracellular ROS ameliorates the MAPK signaling pathway in a human arterial SMC (HASMC) model. Nonetheless, whether ROS scavenger attenuates PCS-triggered inflammasome activation and eicosanoid inflammation in the UVC process remains unknown. Patients with lower extremity amputation were categorized into CKD and normal control group according to renal function. We used immunohistochemistry stain to analyze UVC in arterial specimens, including oxidative injury (8-hydroxy-2'-deoxyguanosine (8-OHdG) and internal EL disruption), cytosolic phospholipase A2 (cPLA2), cyclooxygenase 2 (COX2), interleukin-1 beta (IL-1ß), caspase-1 and NLRP3. To simulate the patho-mechanism of human UVC, the therapeutic effects of ROS scavenger on PCS-triggered inflammatory pathways was explored in a HASMC model. We found CKD patients had higher circulating levels of PCS and an increase in medial arterial calcification than the control group. In CKD arteries, the severity of UVC corresponded with expressions of oxidative EL disruption and 8-OHdG. Furthermore, coupling expressions of cPLA2 and COX2 were accentuated in CKD arteries, indicative of eicosanoid inflammation. Notably, tissue expressions of IL-1ß, caspase-1 and NLRP3 were enhanced in parallel with UVC severity, indicative of inflammasome activation. From bedside to bench, ROS scavenger attenuates PCS-activated expressions of cPLA2/COX2, pro-caspase-1 and NLRP3 in the HASMC model. UVC as an inevitable outcome is predictive of death in CKD patients. Nonetheless, UVC remain pharmacoresistant despite the evolution of treatment for mineral-parathyroid hormone-vitamin D axis. Beyond the mineral dysregulation, the stimulation of pro-oxidant PCS alone results in eicosanoid inflammation and inflammasome activation. Concerning the key role of Caspase-1 in pyroptosis, cell fates of HASMC in uremic milieu are not limited to apoptosis and osteogenesis. In view of this, reducing ROS and PCS may act as a therapeutic strategy for UVC-related cardiovascular events in CKD patients.

12.
J Biol Chem ; 285(30): 23251-64, 2010 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-20466731

RESUMEN

Fructosyltransferases catalyze the transfer of a fructose unit from one sucrose/fructan to another and are engaged in the production of fructooligosaccharide/fructan. The enzymes belong to the glycoside hydrolase family 32 (GH32) with a retaining catalytic mechanism. Here we describe the crystal structures of recombinant fructosyltransferase (AjFT) from Aspergillus japonicus CB05 and its mutant D191A complexes with various donor/acceptor substrates, including sucrose, 1-kestose, nystose, and raffinose. This is the first structure of fructosyltransferase of the GH32 with a high transfructosylation activity. The structure of AjFT comprises two domains with an N-terminal catalytic domain containing a five-blade beta-propeller fold linked to a C-terminal beta-sandwich domain. Structures of various mutant AjFT-substrate complexes reveal complete four substrate-binding subsites (-1 to +3) in the catalytic pocket with shapes and characters distinct from those of clan GH-J enzymes. Residues Asp-60, Asp-191, and Glu-292 that are proposed for nucleophile, transition-state stabilizer, and general acid/base catalyst, respectively, govern the binding of the terminal fructose at the -1 subsite and the catalytic reaction. Mutants D60A, D191A, and E292A completely lost their activities. Residues Ile-143, Arg-190, Glu-292, Glu-318, and His-332 combine the hydrophobic Phe-118 and Tyr-369 to define the +1 subsite for its preference of fructosyl and glucosyl moieties. Ile-143 and Gln-327 define the +2 subsite for raffinose, whereas Tyr-404 and Glu-405 define the +2 and +3 subsites for inulin-type substrates with higher structural flexibilities. Structural geometries of 1-kestose, nystose and raffinose are different from previous data. All results shed light on the catalytic mechanism and substrate recognition of AjFT and other clan GH-J fructosyltransferases.


Asunto(s)
Aspergillus/enzimología , Biocatálisis , Dominio Catalítico , Hexosiltransferasas/química , Hexosiltransferasas/metabolismo , Secuencia de Aminoácidos , Cristalografía por Rayos X , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Glucosa/metabolismo , Glucosa/farmacología , Glicósido Hidrolasas/química , Glicósido Hidrolasas/metabolismo , Hexosiltransferasas/antagonistas & inhibidores , Modelos Moleculares , Datos de Secuencia Molecular , Relación Estructura-Actividad
13.
Diagnostics (Basel) ; 11(2)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670413

RESUMEN

BACKGROUND: The risk of cardiovascular (CV) and fatal events remains extremely high in patients with maintenance hemodialysis (MHD), and the growth differentiation factor 15 (GDF15) has emerged as a valid risk stratification biomarker. We aimed to develop a GDF15-based risk score as a death prediction model for MHD patients. METHODS: Age, biomarker levels, and clinical parameters were evaluated at study entry. One hundred and seventy patients with complete information were finally included for data analysis. We performed the Cox regression analysis of various prognostic factors for mortality. Then, age, GDF15, and robust clinical predictors were included as a risk score model to assess the predictive accuracy for all-cause and CV death in the receiver operating characteristic (ROC) curve analysis. RESULTS: Age, GDF15, and albumin were significantly associated with higher all-cause and CV mortality risk that were combined as a risk score model. The highest tertile of GDF-15 (>1707.1 pg/mL) was associated with all-cause mortality (adjusted hazard ratios (aHRs): 3.06 (95% confidence interval (CI): 1.20-7.82), p < 0.05) and CV mortality (aHRs: 3.11 (95% CI: 1.02-9.50), p < 0.05). The ROC analysis of GDF-15 tertiles for all-cause and CV mortality showed 0.68 (95% CI = 0.59 to 0.77) and 0.68 (95% CI = 0.58 to 0.79), respectively. By contrast, the GDF15-based prediction model for all-cause and CV mortality showed 0.75 (95% CI: 0.67-0.82) and 0.72 (95% CI: 0.63-0.81), respectively. CONCLUSION: Age, GDF15, and hypoalbuminemia predict all-cause and CV death in MHD patients, yet a combination scoring system provides more robust predictive powers. An elevated GDF15-based risk score warns clinicians to determine an appropriate intervention in advance. In light of this, the GDF15-based death prediction model could be developed in the artificial intelligence-based precision medicine.

14.
Diagnostics (Basel) ; 11(7)2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34359336

RESUMEN

BACKGROUND: The risk of skeletal events is rising in parallel with the burden of chronic kidney disease and mineral bone disorder (CKD-MBD), whilst the role of the fat-bone axis in CKD-MBD remains elusive. Adiponectin derived from adipocytes has emerged as a valid biomarker of low bone mineral density and increased marrow adiposity. We aimed to explore the association between adiponectin and bone fracture (BF) risks in patients with maintenance hemodialysis (MHD). METHODS: Serum concentrations of adiponectin and bio-clinical data were determined at study entry. The Cox proportional hazard regression analyses were used to assess unadjusted and adjusted hazard ratios (aHRs) of adiponectin and various clinical predictors for BF risks. The predictive accuracy of adiponectin for BF events was evaluated by receiver operating characteristic (ROC) curve analysis. RESULTS: Age and serum concentrations of adiponectin, phosphate, and intact parathyroid hormone were significantly associated with higher risks of BF. With respect to the risk of BF events, the cumulative event-free survival curves differed significantly between the high and low concentration groups of adiponectin (p = 0.02). In multivariable analysis, higher adiponectin levels were associated with an incremental risk of BF (adjusted hazard ratios (aHRs): 1.08 (95% confidence interval (CI): 1.01-1.15, p < 0.05). The ROC analysis of adiponectin cutoff point concentration (18.15 ug/mL) for prediction of BF showed 0.66 (95% CI = 0.49 to 0.84). CONCLUSION: Adiponectin was associated with an incremental risk of BF that could serve as a potential predictor of BF in MHD patients. In the high-risk population with hyperphosphatemia, an elevated adiponectin level could alert clinicians to the urgent need to correct mineral dysregulation and undertake further bone survey.

15.
Toxins (Basel) ; 13(7)2021 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-34357951

RESUMEN

Patients with chronic kidney disease (CKD), especially those undergoing hemodialysis, are at a considerably high risk of bone fracture events. Experimental data indicate that uremic toxins intricately involved in bone-related proteins exert multi-faced toxicity on bone cells and tissues, leading to chronic kidney disease-mineral and bone disorder (CKD-MBD). Nonetheless, information regarding the association between p-cresyl sulfate (PCS), non-hepatic alkaline phosphatase (NHALP) and skeletal events remains elusive. We aim to explore the association between PCS, NHALP and risk of bone fracture (BF) in patients with hemodialysis. Plasma concentrations of PCS and NHALP were ascertained at study entry. Cox proportional hazard regression analyses were used to determine unadjusted and adjusted hazard ratios (aHRs) of PCS for BF risk. In multivariable analysis, NHALP was associated with incremental risks of BFs [aHR: 1.06 (95% CI: 1.01-1.11)]. The association between the highest PCS tertile and BF risk remained robust [aHR: 2.87 (95% CI: 1.02-8.09)]. With respect to BF events, the interaction between NHALP and PCS was statistically significant (p value for the interaction term < 0.05). In addition to mineral dysregulation and hyperparathyroidism in hemodialysis patients, higher circulating levels of PCS and NHALP are intricately associated with incremental risk of BF events, indicating that a joint evaluation is more comprehensive than single marker. In light of the extremely high prevalence of CKD-MBD in the hemodialysis population, PCS may act as a pro-osteoporotic toxin and serve as a potential surrogate marker for skeletal events.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Cresoles/metabolismo , Fracturas Óseas/metabolismo , Insuficiencia Renal Crónica/metabolismo , Ésteres del Ácido Sulfúrico/metabolismo , Biomarcadores/sangre , Enfermedades Óseas , Huesos/metabolismo , Cresoles/sangre , Fracturas Óseas/complicaciones , Humanos , Indicán/sangre , Persona de Mediana Edad , Minerales , Diálisis Renal , Sulfatos , Ésteres del Ácido Sulfúrico/sangre , Toxinas Biológicas/metabolismo , Uremia/metabolismo , Tóxinas Urémicas
16.
Front Med (Lausanne) ; 7: 99, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32292788

RESUMEN

Background: Cardiac sympathetic response (CSR) and malnutrition-inflammation syndrome (MIS) score are validated assessment tools for patients' health condition. We aim to evaluate the joint effect of CSR and MIS on all-cause and cardiovascular (CV) mortality in patients with hemodialysis (HD). Methods: Changes in normalized low frequency (ΔnLF) during HD were utilized for quantification of CSR. Unadjusted and adjusted hazard ratios (aHRs) of mortality risks were analyzed in different groups of ΔnLF and MIS score. Results: In multivariate analysis, higher ΔnLF was related to all-cause, CV and sudden cardiac deaths [aHR: 0.78 (95% confidence interval (CI): 0.72-0.85), 0.78 (95% CI: 0.70-0.87), and 0.74 (95% CI: 0.63-0.87), respectively]. Higher MIS score was associated with incremental risks of all-cause, CV and sudden cardiac deaths [aHR: 1.36 (95% CI: 1.13-1.63), 1.33 (95% CI: 1.06 - 1.38), and 1.50 (95% CI: 1.07-2.11), respectively]. Patients with combined lower ΔnLF (≤6.8 nu) and higher MIS score were at the greatest risk of all-cause and CV mortality [aHR: 5.64 (95% CI: 1.14-18.09) and 5.86 (95% CI: 1.64-13.65), respectively]. Conclusion: Our data indicate a joint evaluation of CSR and MIS score to identify patients at high risk of death is more comprehensive and convincing. Considering the extremely high prevalence of cardiac autonomic neuropathy and malnutrition-inflammation cachexia in HD population, a non-invasive monitoring system composed of CSR analyzer and MIS score calculator should be developed in the artificial intelligence-based prediction of clinical events.

17.
Int J Biol Macromol ; 165(Pt A): 495-505, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32991903

RESUMEN

Glucuronoxylomannan (AAPS) from the edible wood ear mushroom Auricularia auricula-judae has been demonstrated to exhibit immunostimulatory properties through its binding to TLR4. However, the mechanisms of immune modulation by AAPS in mammalian cells remains unclear. In the present study, we demonstrated that AAPS induced immunostimulatory effects were regulated by reactive oxygen species, mitogen-activated protein kinases, protein kinase C-α and NF-κB. AAPS remarkably increased the phagocytosis and bactericidal activity of macrophages. In lipopolysaccharide-activated macrophages, AAPS induced endotoxin tolerance like effect characterized by the downregulation of nitric oxide, interleukin-6 and TNF-α via the downregulation of NF-κB activation. Our findings provide firm scientific evidences for the immunoenhancing properties of wood ear mushroom, and the potential of AAPS to be strong candidates for the development of new carbohydrate-based nutraceutical supplements in the management of immunity related disorders in the future.


Asunto(s)
Auricularia/química , Lipopolisacáridos/toxicidad , Macrófagos/inmunología , Fagocitosis/efectos de los fármacos , Polisacáridos/farmacología , Animales , Tolerancia a Medicamentos , Ratones , Polisacáridos/química , Células RAW 264.7
18.
Toxins (Basel) ; 12(6)2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32498221

RESUMEN

The nephrotoxicity of aristolochic acids (AAs), p-cresyl sulfate (PCS) and indoxyl sulfate (IS) were well-documented, culminating in tubulointerstitial fibrosis (TIF), advanced chronic kidney disease (CKD) and fatal urothelial cancer. Nonetheless, information regarding the attenuation of AAs-induced nephropathy (AAN) and uremic toxin retention is scarce. Propolis is a versatile natural product, exerting anti-oxidant, anti-cancer and anti-fibrotic properties. We aimed to evaluate nephroprotective effects of propolis extract (PE) in a murine model. AAN was developed to retain circulating PCS and IS using C57BL/6 mice, mimicking human CKD. The kidney sizes/masses, renal function indicators, plasma concentrations of PCS/IS, tissue expressions of TIF, α-SMA, collagen IaI, collagen IV and signaling pathways in transforming growth factor-ß (TGF-ß) family were analyzed among the control, PE, AAN, and AAN-PE groups. PE ameliorated AAN-induced renal atrophy, renal function deterioration, TIF, plasma retention of PCS and IS. PE also suppressed α-SMA expression and deposition of collagen IaI and IV in the fibrotic epithelial-mesenchymal transition. Notably, PE treatment in AAN model inhibited not only SMAD 2/3-dependent pathways but also SMAD-independent JNK/ERK activation in the signaling cascades of TGF-ß family. Through disrupting fibrotic epithelial-mesenchymal transition and TGF-ß signaling transduction pathways, PE improves TIF and thereby facilitates renal excretion of PCS and IS in AAN. In light of multi-faced toxicity of AAs, PE may be capable of developing a new potential drug to treat CKD patients exposed to AAs.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Túbulos Renales/efectos de los fármacos , Própolis/farmacología , Insuficiencia Renal Crónica/tratamiento farmacológico , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , Uremia/tratamiento farmacológico , Animales , Ácidos Aristolóquicos , Cresoles/sangre , Modelos Animales de Enfermedad , Transición Epitelial-Mesenquimal/efectos de los fármacos , Fibrosis , Indicán/sangre , Túbulos Renales/enzimología , Túbulos Renales/patología , Ratones Endogámicos C57BL , Insuficiencia Renal Crónica/inducido químicamente , Insuficiencia Renal Crónica/enzimología , Insuficiencia Renal Crónica/patología , Transducción de Señal , Ésteres del Ácido Sulfúrico/sangre , Factor de Crecimiento Transformador beta/metabolismo , Uremia/inducido químicamente , Uremia/metabolismo , Uremia/patología
19.
Toxins (Basel) ; 12(8)2020 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-32722241

RESUMEN

Osteogenesis in human arterial smooth muscle cell (HASMC) is a key feature of uremic vascular calcification (UVC). Concerning pro-oxidant properties of p-cresyl sulfate (PCS), the therapeutic effect of reactive oxygen species (ROS) scavenger on PCS triggered inflammatory signaling transduction in osteogenesis was investigated in this translational research. Based on severity level of chronic kidney disease (CKD), arterial specimens with immunohistochemistry stain were quantitatively analyzed for UVC, oxidative injury and osteogenesis along with PCS concentrations. To mimic human UVC, HASMC model was used to explore whether PCS-induced ROS could trigger mitogen-activated protein kinase (MAPK) pathways with nuclear factor-κB (NF-κB) translocation that drive context-specific gene/protein expression, including Runt-related transcription factor 2 (Runx2) and alkaline phosphatase (ALP). In parallel with PCS accumulation, CKD arteries corresponded with UVC severity, oxidative DNA damage (8-hydroxy-2'-deoxyguanosine), Runx2 and ALP. PCS directly phosphorylated extracellular signal-regulated kinase (ERK)/c-Jun N-terminal kinase (JNK)/P38 (pERK/pJNK/pP38) and modulated NF-κB translocation to promote expressions of Runx2 and ALP in HASMC. Notably, intracellular ROS scavenger attenuated pERK signaling cascade and downstream osteogenic differentiation. Collectively, our data demonstrate PCS induces osteogenesis through triggering intracellular ROS, pERK/pJNK/pP38 MAPK pathways and NF-κB translocation to drive Runx2 and ALP expressions, culminating in UVC. Beyond mineral dysregulation, osteocytic conversion in HASMC could be the stimulation of PCS. Thus PCS may act as a pro-osteogenic and pro-calcific toxin. From the perspective of translational medicine, PCS and intracellular ROS could serve as potential therapeutic targets for UVC in CKD patients.


Asunto(s)
Cresoles/metabolismo , Miocitos del Músculo Liso/metabolismo , Osteogénesis , Especies Reactivas de Oxígeno/metabolismo , Insuficiencia Renal Crónica/metabolismo , Ésteres del Ácido Sulfúrico/metabolismo , Uremia/metabolismo , Calcificación Vascular/metabolismo , Anciano , Anciano de 80 o más Años , Arterias/citología , Células Cultivadas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/cirugía , Transducción de Señal , Uremia/complicaciones , Calcificación Vascular/etiología
20.
Front Med (Lausanne) ; 7: 78, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32266272

RESUMEN

Background: Uremic vascular calcification (UVC) is reminiscent of osteogenesis and apoptosis in vascular smooth muscle cell (VSMC). We aimed to identify how circulating procalcific particles dramatically leak into VSMC layer in human tissue models of vascular rings. Methods: According to baseline estimated glomerular filtration rate (eGFR), patients following lower extremity amputation were divided into three groups: normal renal function (eGFR ≧ 60 ml/min), mild-to-moderate (15 ml/min < eGFR ≧ 60 ml/min) and severe chronic kidney disease (CKD) (eGFR ≦ 15 ml/min). Arterial specimens with immunohistochemistry stain were quantitatively analyzed for UVC, internal elastic lamina (EL) disruption, α-SMA, osteogenesis, apoptosis, and oxidative injury. Correlations among UVC severity, eGFR, EL disruption, osteogenesis, and oxidative injury were investigated. Results: CKD arteries were associated with eGFR-dependent EL disruption corresponding to UVC severity. CKD arteries exhibited lower α-SMA, higher expressions of caspase-3 and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), indicative of contractile VSMC loss, and apoptosis. Enhanced expressions of alkaline phosphatase and Runx2 were presented in VSMCs of CKD arteries, indicative of osteogenic differentiation. Above eGFR-dependent UVC and EL disruption correlated expressions of 8-hydroxy-2'-deoxyguanosine (8-OHdG), indicating oxidative EL injury promoted procalcific processes. Conclusions: Circulating uremic milieu triggers vascular oxidative stress, leading to progressive internal EL disruption as a key event in disabling VSMC defense mechanisms and catastrophic mineral ion influx into VSMC layer. Oxidative EL injury begins in early CKD, corresponding with active VSMC re-programming, apoptosis, and ultimately irremediable UVC. In light of this, therapeutic strategies targeting oxidative tissue injury might be of vital importance to hinder the progression of UVC related cardiovascular events.

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