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1.
Acta Biochim Biophys Sin (Shanghai) ; 56(6): 833-843, 2024 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-38716542

RESUMEN

Acute rejection is an important factor affecting the survival of recipients after liver transplantation. Salidroside has various properties, including anti-inflammatory, antioxidant, and hepatoprotective properties. This study aims to investigate whether salidroside can prevent acute rejection after liver transplantation and to examine the underlying mechanisms involved. An in vivo acute rejection model is established in rats that are pretreated with tacrolimus (1 mg/kg/d) or salidroside (10 or 20 mg/kg/d) for seven days after liver transplantation. In addition, an in vitro experiment is performed using neutrophils incubated with salidroside (1, 10, 50 or 100 µM). Hematoxylin-eosin staining, terminal deoxynucleotidyl transferase dUTP nick-end labeling staining, immunosorbent assays, immunofluorescence analysis, Evans blue staining, and western blot analysis are performed to examine the impact of salidroside on NET formation and acute rejection in vitro and in vivo. We find that Salidroside treatment reduces pathological liver damage, serum aminotransferase level, and serum levels of IL-1ß, IL-6, and TNF-α in vivo. The expressions of proteins associated with the HMGB1/TLR-4/MAPK signaling pathway (HMGB1, TLR-4, p-ERK1/2, p-JNK, p-P38, cleaved caspase-3, cleaved caspase-9, Bcl-2, Bax, IL-1ß, TNF-α, and IL-6) are also decreased after salidroside treatment. In vitro experiments show that the release of HMGB1/TLR-4/MAPK signaling pathway-associated proteins from neutrophils treated with lipopolysaccharide is decreased by salidroside. Moreover, salidroside inhibits NETosis and protects against acute rejection by regulating the HMGB1/TLR-4/MAPK signaling pathway. Furthermore, salidroside combined with tacrolimus has a better effect than either of the other treatments alone. In summary, salidroside can prevent acute liver rejection after liver transplantation by reducing neutrophil extracellular trap development through the HMGB1/TLR-4/MAPK signaling pathway.


Asunto(s)
Trampas Extracelulares , Glucósidos , Rechazo de Injerto , Proteína HMGB1 , Trasplante de Hígado , Neutrófilos , Fenoles , Receptor Toll-Like 4 , Animales , Fenoles/farmacología , Glucósidos/farmacología , Trampas Extracelulares/efectos de los fármacos , Trampas Extracelulares/metabolismo , Rechazo de Injerto/prevención & control , Rechazo de Injerto/patología , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/metabolismo , Proteína HMGB1/metabolismo , Receptor Toll-Like 4/metabolismo , Masculino , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Ratas , Ratas Sprague-Dawley , Hígado/efectos de los fármacos , Hígado/patología , Hígado/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Apoptosis/efectos de los fármacos
2.
J Am Chem Soc ; 146(14): 10142-10149, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38536870

RESUMEN

Saturated bicyclic compounds make up a valuable class of building blocks in the development of agrochemicals and pharmaceuticals. Here, we present the synthesis of borylated bicyclo[2.1.1]hexanes via crossed [2 + 2]-cycloaddition. Due to the presence of the C-B bond, a variety of structures can be easily prepared that are not accessible by other methods. Moreover, a rare photo-ene reaction is also disclosed, allowing for the diastereoselective synthesis of trisubstituted borylated cyclopentanes.

3.
Ann Surg Oncol ; 31(4): 2654-2655, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38273175

RESUMEN

BACKGROUND: Duodenum-preserving pancreatic head resection (DPPHR) serves as a surgical intervention for managing benign and low-grade malignant neoplasms located in the head of the pancreas. This surgical approach enables the thorough excision of pancreatic head lesions, reducing the necessity for digestive tract reconstruction and enhancing the patient's quality of life.1 Performing a minimally invasive DPPHR is a complex surgical procedure, particularly when safeguarding the bile duct and the pancreaticoduodenal arterial arch. Robotic surgery is among the latest innovations in minimally invasive surgery and is widely used in many surgical specialties. It offers advantages such as rotatable surgical instruments, muscle tremor filters and up to 10-15 times three dimensional (3D) visual field,2 and achieves high flexibility and accuracy in surgical operations. Indocyanine green (ICG) fluorescence imaging technology is also applied to provide real-time intraoperative assessment of the biliary system and blood supply, which helps maintain the biliary system's integrity.3,4 We first report the complete procedure of ICG applied to the da Vinci robotic Xi system for preserving the DPPHR. METHODS: A 48-year-old female patient was diagnosed with pancreatic duct stones, chronic pancreatitis, and pancreatogenic diabetes. Enhanced computed tomography (CT) scans revealed pancreatic head stones, pancreatic atrophy, scattered calcifications, and a dilated pancreatic duct. An attempt at endoscopic retrograde cholangiopancreatography (ERCP) treatment was abandoned during hospitalization due to unsuccessful catheterization. Following informed consent from the patient and her family, a robotic DPPHR was conducted utilizing ICG fluorescence imaging technology. Approximately 60 min before the surgery, 2 mg of ICG was injected via the peripheral vein. The individual was positioned in a reclined posture with the upper part of the bed raised to an angle of 30° and a leftward tilt of 15°. Upon entering the abdominal cavity, existing adhesions were meticulously separated and the gastrocolic ligament was opened to expose the pancreas. The lower part of the pancreas was separated and the superior mesenteric vein (SMV) was identified at the inferior boundary of the pancreatic neck. The pancreas was cut upward and the pancreatic duct was severed using scissors. Dissection of the lateral wall of the portal vein-SMV in the pancreatic head segment was performed. Meticulous dissection was carried out along the pancreatic tissue, retracting the uncinate process of the pancreas in an upward and rightward direction. During the dissection, caution was exercised to protect the anterior and posterior pancreaticoduodenal arterial arch. By using ICG fluorescence imaging, the path of the common bile duct was identified and verified. Caution was exercised to avoid injuring the bile duct. After isolating the CBD, the head and uncinate process of the pancreas was entirely excised. Under the fluorescence imaging mode, the wholeness of the CBD was scrutinized for any potential seepage of the contrast agent. Ultimately, a Roux-en-Y end-to-side pancreaticojejunostomy (duct to mucosa) was executed. RESULTS: The surgery took 265 min and the estimated blood loss was about 150 mL. Without any postoperative complications, the patient was released from the hospital 13 days following the surgery. Postoperative pathology confirmed pancreatic duct stones and chronic pancreatitis. We have successfully performed four cases of robotic DPPHR using this technique, with only one patient experiencing a postoperative complication of pulmonary embolism. All patients were discharged successfully without any further complications. CONCLUSIONS: Employing ICG fluorescence imaging in a robotic DPPHR has been demonstrated to be both secure and achievable. This technique potentially provides novel therapeutic perspectives, particularly for patients with ambiguous delineation between pancreatic and biliary ductal structures.


Asunto(s)
Enfermedades Pancreáticas , Neoplasias Pancreáticas , Pancreatitis Crónica , Procedimientos Quirúrgicos Robotizados , Humanos , Femenino , Persona de Mediana Edad , Verde de Indocianina , Calidad de Vida , Neoplasias Pancreáticas/patología , Pancreatectomía/métodos , Pancreatitis Crónica/diagnóstico por imagen , Pancreatitis Crónica/cirugía , Enfermedades Pancreáticas/cirugía , Duodeno/cirugía
4.
J Am Chem Soc ; 145(46): 25061-25067, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37939224

RESUMEN

A strategy to achieve photosensitized [2 + 2] cycloadditions by means of temporary ring constraint is reported. Specifically, a dioxaborole is prepared that undergoes [2 + 2] cycloadditions with a wide variety of alkenes. This strategy overcomes some challenges with the cycloaddition of acyclic substrates. The products can be easily transformed into cyclobutyl diols or 1,4-dicarbonyl compounds; the latter represents a formal alkene vicinal diacylation. The synthetic utility of this method is shown in the synthesis of valuable heterocycles and biatriosporin D.

5.
Invest Ophthalmol Vis Sci ; 64(13): 19, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37824136

RESUMEN

Purpose: To explore the mechanism underlying IL-8-induced neutrophil extracellular trap (NET) formation in patients with ocular-active Behçet's disease (BD) and the effect of inhibiting NET formation on the severity of inflammation in experimental autoimmune uveitis (EAU) mice. Methods: The serum extracellular DNA and neutrophil elastase (NE) and IL-8 levels in patients with ocular-active BD, the expression of myeloperoxidase, NE, and histone H3Cit in IL-8-induced neutrophils isolated from healthy controls, and the effects of NETs on HMC3 cells were detected. Female C57BL/6J mice were immunized with IRBP651-670 to induce EAU and EAU mice received intravitreal injection of the CXCR2 (IL-8 receptor) antagonist SB225002 or PBS. The serum levels of extracellular DNA, NE, and keratinocyte-derived chemokine (the mouse ortholog of human IL-8) and expression of myeloperoxidase, NE, and histone H3Cit in mouse retinas were detected. Disease severity was evaluated by clinical and histopathological scores. Results: Serum keratinocyte-derived chemokine expression levels in EAU mice and IL-8 expression levels in patients with ocular-active BD increased. IL-8 notably increased NET formation in a dose-dependent manner through an nicotinamide adenine dinucleotide phosphate oxidase and mitogen-activated protein kinase pathway dependent mechanism. IL-8-induced NET formation damaged HMC3 cells in vitro. Pretreatment with SB225002 notably ameliorated the production of NETs in EAU mice. Conclusions: Our data confirm that NET formation is induced by IL-8. IL-8-induced NET formation was found to be related to mitogen-activated protein kinase and nicotinamide adenine dinucleotide phosphate pathways. Pretreatment with the CXCR2 antagonist SB225002 alleviated neutrophil infiltration and suppressed NET formation in EAU mice.


Asunto(s)
Síndrome de Behçet , Trampas Extracelulares , Interleucina-8 , Uveítis , Animales , Femenino , Humanos , Ratones , ADN/metabolismo , Trampas Extracelulares/metabolismo , Histonas , Interleucina-8/metabolismo , Ratones Endogámicos C57BL , Proteínas Quinasas Activadas por Mitógenos/metabolismo , NADP/metabolismo , Neutrófilos , Peroxidasa/metabolismo , Uveítis/tratamiento farmacológico
6.
J Am Chem Soc ; 145(32): 18029-18035, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37530761

RESUMEN

Ferrocene is perhaps the most popular and well-studied organometallic molecule, but our understanding of its structure and electronic properties has not changed for more than 70 years. In particular, all previous attempts of chemically oxidizing pure ferrocene by binding directly to the iron center have been unsuccessful, and no significant change in structure or magnetism has been reported. Using a metal organic framework host material, we were able to fundamentally change the electronic and magnetic structure of ferrocene to take on a never-before observed physically stretched/bent high-spin Fe(II) state, which readily accepts O2 from air, chemically oxidizing the iron from Fe(II) to Fe(III). We also show that the binding of oxygen is reversible through temperature swing experiments. Our analysis is based on combining Mößbauer spectroscopy, extended X-ray absorption fine structure, in situ infrared, SQUID, thermal gravimetric analysis, and energy dispersive X-ray fluorescence spectroscopy measurements with ab initio modeling.

7.
Inorg Chem ; 62(24): 9640-9648, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37265371

RESUMEN

Bismuth oxyhalides are a promising class of photocatalysts for harvesting solar energy. These materials are often synthesized in aqueous media with poor synthetic control resulting from the extremely fast nucleation and growth rates of the particles. These fast rates are caused by the rapid precipitation of bismuth salts with free halide ions. We have developed water-soluble precursors combining bismuth with either chlorine or bromine atoms in the same metal-organic complex. With the application of heat, halide ions are released, which then precipitate with bismuth ions as BiOX (X = Cl, Br). By controlling the halide ion formation rate, the nucleation and growth rates of BiOX materials can be tuned to provide synthetic control. The diverse potential of these precursors is demonstrated by synthesizing BiOX in three ways: aqueous colloidal synthesis, solid-state decomposition, and fabrication of films of BiOX via spray pyrolysis of the aqueous precursor solutions. These broadly applicable single-source precursors will enhance the ability to synthesize future BiOX materials with controlled morphologies.

8.
Clin Immunol ; 251: 109325, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37030526

RESUMEN

Ischemia-reperfusion injury (IRI) is one of the most common complications in liver transplantation. METTL3 regulates inflammation and cellular stress response by modulating RNA m6A modification level. Here, the study aimed to investigate the role and mechanism of METTL3 in IRI after rat orthotopic liver transplantation. The total RNA m6A modification and METTL3 expression level was consistently down-regulated after 6 h or 24 h reperfusion in OLT, which is negatively associated with the hepatic cell apoptosis. Functionally, METTL3 pretreatment in donor significantly inhibited liver grafts apoptosis, improved liver function and depressed the proinflammatory cytokine/chemokine expression. Mechanistically, METTL3 inhibited apoptosis of grafts via upregulating HO-1. Moreover, m6A dot blot and MeRIP-qPCR assay revealed that METTL3 promoted HO-1 expression in an m6A-dependent manner. In vitro, METTL3 alleviated hepatocytes apoptosis by upregulating HO-1 under hypoxia/reoxygenation condition. Taken together, these findings demonstrate that METTL3 ameliorates rat OLT-stressed IRI by inducing HO-1 in an m6A-dependent manner, highlighting a potential target for IRI in liver transplantation.


Asunto(s)
Trasplante de Hígado , Daño por Reperfusión , Ratas , Animales , Trasplante de Hígado/efectos adversos , Hígado/metabolismo , Inflamación/metabolismo , Daño por Reperfusión/genética , Daño por Reperfusión/metabolismo , ARN/metabolismo
9.
Am J Transplant ; 23(3): 336-352, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36695693

RESUMEN

Acute rejection (AR) is an important factor that leads to poor prognosis after liver transplantation (LT). Macrophage M1-polarization is an important mechanism in AR development. MicroRNAs play vital roles in disease regulation; however, their effects on macrophages and AR remain unclear. In this study, rat models of AR were established following LT, and macrophages and peripheral blood mononuclear cells were isolated from rats and humans, respectively. We found miR-449a expression to be significantly reduced in macrophages and peripheral blood mononuclear cells. Overexpression of miR-449a not only inhibited the M1-polarization of macrophages in vitro but also improved the AR of transplant in vivo. The mechanism involved inhibiting the noncanonical nuclear factor-kappaB (NF-κB) pathway. We identified procollagen-lysine1,2-oxoglutarate5-dioxygenase 1 (PLOD1) as a target gene of miR-449a, which could reverse miR-449a's inhibition of macrophage M1-polarization, amelioration of AR, and inhibition of the NF-κB pathway. Overall, miR-449a inhibited the NF-κB pathway in macrophages through PLOD1 and also inhibited the M1-polarization of macrophages, thus attenuating AR after LT. In conclusion, miR-449a and PLOD1 may be new targets for the prevention and mitigation of AR.


Asunto(s)
Trasplante de Hígado , MicroARNs , Animales , Humanos , Ratas , Leucocitos Mononucleares/metabolismo , Macrófagos/metabolismo , MicroARNs/genética , FN-kappa B/metabolismo , Procolágeno/metabolismo , Procolágeno/farmacología
10.
Front Immunol ; 13: 1054753, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36466888

RESUMEN

Many end-stage liver disease etiologies are attributed to robust inflammatory cell recruitment. Neutrophils play an important role in inflammatory infiltration and neutrophil phagocytosis, oxidative burst, and degranulation. It has also been suggested that neutrophils may release neutrophil extracellular traps (NETs) to kill pathogens. It has been proven that neutrophil infiltration within the liver contributes to an inflammatory microenvironment and immune cell activation. Growing evidence implies that NETs are involved in the progression of numerous complications of liver transplantation, including ischemia-reperfusion injury, acute rejection, thrombosis, and hepatocellular carcinoma recurrence. NETs are discussed in this comprehensive review, focusing on their effects on liver transplantation complications. Furthermore, we discuss NETs as potential targets for liver transplantation therapy.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Trampas Extracelulares , Neoplasias Hepáticas , Trasplante de Hígado , Humanos , Trasplante de Hígado/efectos adversos , Neutrófilos , Microambiente Tumoral
11.
J Am Chem Soc ; 144(41): 18790-18796, 2022 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-36200833

RESUMEN

A strategy for the photosensitized cycloaddition of alkenylboronates and allylic alcohols by a temporary coordination is presented. The process allows for the synthesis of a diverse range of cyclobutylboronates. Key to development of these reactions is the temporary coordination of the allylic alcohol to the Bpin unit. This not only allows for the reaction to proceed in an intramolecular manner but also allows for high levels of stereo and regiocontrol. A key aspect of these studies is the utility of the cycloadducts in the synthesis of complex natural products artochamin J and piperarborenine B.


Asunto(s)
Productos Biológicos , Ésteres , Reacción de Cicloadición , Boro
12.
Acta Biochim Biophys Sin (Shanghai) ; 54(8): 1148-1158, 2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-35959879

RESUMEN

The occurrence of acute rejection after liver transplantation seriously impairs the prognosis of patients. miRNA is involved in many physiological and pathological processes of the body, but the mechanism of miRNA action in liver transplantation is not completely clear. In this study, we discuss the role of miR-505-5p in acute rejection after liver transplantation and its putative regulating mechanism. We construct an allogeneic rat liver transplantation model, observe the morphological and pathological changes in liver tissue, detect the expression levels of Myd88, miR-505-5p, IL-10 and TNF-α, and confirm that Myd88 is one of the direct targets of miR-505. The effects of miR-505-5p on the Myd88/TRAF6/NF-κB and MAPK pathways are detected both in vitro and in vivo, and the standard markers of Kupffer cell M1/M2 polarization are also detected. The results of qRT-PCR experiments show that miR-505-5p has a downward trend in rats with acute rejection. Western blot analysis reveals that over-expression of miR-505-5p induces the reduction of NF-κB and MAPK pathways both in vitro and in vivo. The role of miR-505-5p in alleviating acute rejection after transplantation may be accomplished by inducing M2-type polarization of Kupffer cells. In conclusion, we find that miR-505-5p alleviates acute rejection of liver transplantation by inducing M2 polarization of macrophages via the Myd88/TRAF6 axis, which suggests a potential strategy based on miRNAs in the follow-up treatment of liver transplantation.


Asunto(s)
Trasplante de Hígado , MicroARNs , Animales , Interleucina-10/metabolismo , Macrófagos del Hígado/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , FN-kappa B/metabolismo , Ratas , Factor 6 Asociado a Receptor de TNF/genética , Factor 6 Asociado a Receptor de TNF/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
13.
Sci Rep ; 12(1): 13973, 2022 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-35978104

RESUMEN

Salidroside has anti-inflammatory, antioxidant and hepatoprotective properties. However, its effect on hepatic ischemia-reperfusion injury (IRI), an unavoidable side effect associated with liver transplantation, remains undefined. Here, we aimed to determine whether salidroside alleviates hepatic IRI and elucidate its potential mechanisms. We used both in vivo and in vitro assays to assess the effect and mechanisms of salidroside on hepatic IRI. Hepatic IRI rat models were pretreated with salidroside (5, 10 or 20 mg/kg/day) for 7 days following liver transplantation while hypoxia/reoxygenation (H/R) model of RAW 264.7 macrophages were pretreated with salidroside (1, 10 or 50 µM). The effect of salidroside on hepatic IRI was assessed using hematoxylin-eosin staining, terminal deoxynucleotidyl transferase dUTP nick-end labeling staining, qRT-PCR, immunosorbent assay and western blotting. Our in vivo assays showed that salidroside significantly reduced pathological liver damage, serum aminotransferase levels and serum levels of IL-1, IL-18 and TNF-α. Besides, salidroside reduced the expression of TLR-4/NF-κB/NLRP3 inflammatory pathway associated proteins (TLR-4, MyD88, p-IKKα, p-IKKß, p-IKK, p-IκBα, p-P65, NLRP3, ASC, Cleaved caspase-1, IL-1ß, IL-18, TNF-α and IL-6) in rats after liver transplantation. On the other hand, data from the in vitro analysis demonstrated that salidroside blocks expression of TLR-4/NF-κB/NLRP3 inflammatory pathway related proteins in the RAW264.7 cells treated with H/R. The salidroside-specific anti-inflammatory effects were partially inhibited by the TLR-4 agonist lipopolysaccharide. Taken together, our study showed that salidroside inhibits hepatic IRI following liver transplantation by modulating the TLR-4/NF-κB/NLRP3 inflammatory pathway.


Asunto(s)
Trasplante de Hígado , Daño por Reperfusión , Animales , Antiinflamatorios/farmacología , Glucósidos , Interleucina-18/metabolismo , Hígado/metabolismo , Trasplante de Hígado/efectos adversos , FN-kappa B/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Fenoles , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/etiología , Daño por Reperfusión/prevención & control , Transducción de Señal , Receptor Toll-Like 4/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
14.
Oxid Med Cell Longev ; 2022: 6489923, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35761872

RESUMEN

Neutrophils participate in the advancement of the human innate immune system and respond to perceived endogenous and exogenous threats. As a response mechanism, neutrophil extracellular traps (NETs) form near pathogens and surrounding tissues during an immune response. Drusen is an important marker of Age-Related Macular Degeneration (AMD) and plays an important role in the course of AMD. Aß1-40 is the main component of drusen. However, the relationship between NETs and AMD or Aß1-40 is unclear. Here, we found elevated levels of NETs in the serum of AMD patients and elevated levels in the serum of mouse models. We also observed the accumulation of neutrophils in the mouse retina. In addition, the production of NETs was inhibited by PAD4 inhibitors, which can alleviate chronic inflammation. Moreover, we confirmed that Aß1-40 can induce NETs formation via the Toll-like receptor 4 (TLR4) and neutrophil NADPH oxidase (NOX) pathways. Our study confirmed that the formation of NETs is induced by Aß1-40, and the results suggest that NETs may play a vital role in AMD pathogenesis.


Asunto(s)
Trampas Extracelulares , Degeneración Macular , Animales , Trampas Extracelulares/metabolismo , Humanos , Degeneración Macular/patología , Ratones , NADPH Oxidasas/metabolismo , Neutrófilos/metabolismo , Receptor Toll-Like 4/metabolismo
15.
Front Immunol ; 13: 823511, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35603144

RESUMEN

Neutrophil extracellular traps (NETs) play important roles in hepatic ischemic reperfusion injury (IRI) and acute rejection (AR)-induced immune responses to inflammation. After liver transplantation, HMGB1, an inflammatory mediator, contributes to the development of AR. Even though studies have found that HMGB1 can promote NET formation, the correlation between NETs and HMGB1 in the development of AR following liver transplantation has not been elucidated. In this study, levels of serum NETs were significantly elevated in patients after liver transplantation. Moreover, we found that circulating levels of NETs were negatively correlated with liver function. In addition, liver transplantation and elevated extracellular HMGB1 promoted NET formation. The HMGB1/TLR-4/MAPK signaling pathway, which is initiated by HMGB1, participates in NET processes. Moreover, in the liver, Kupffer cells were found to be the main cells secreting HMGB1. NETs induced Kupffer cell M1 polarization and decreased the intracellular translocation of HMGB1 by inhibiting DNase-1. Additionally, co-treatment with TAK-242 (a TLR-4 inhibitor) and rapamycin more effectively alleviated the damaging effects of AR following liver transplantation than either drug alone.


Asunto(s)
Trampas Extracelulares , Proteína HMGB1 , Trasplante de Hígado , Trampas Extracelulares/metabolismo , Rechazo de Injerto , Proteína HMGB1/metabolismo , Humanos , Macrófagos del Hígado/metabolismo , Hígado/metabolismo , Neutrófilos , Receptor Toll-Like 4/metabolismo
16.
Angew Chem Int Ed Engl ; 61(25): e202200725, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35446458

RESUMEN

A new strategy for the synthesis of highly versatile cyclobutylboronates via the photosensitized [2+2]-cycloaddition of alkenylboronates and alkenes is presented. The process is mechanistically different from other processes in that energy transfer occurs with the alkenylboronate as opposed to the other alkene. This strategy allows for the synthesis of an array of diverse cyclobutylboronates. The conversion of these adducts to other compounds as well as their utility in the synthesis of melicodenine C is demonstrated.

17.
Acta Crystallogr C Struct Chem ; 78(Pt 4): 257-264, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35380129

RESUMEN

The crystal structures of three ß-halolactic acids have been determined, namely, ß-chlorolactic acid (systematic name: 3-chloro-2-hydroxypropanoic acid, C3H5ClO3) (I), ß-bromolactic acid (systematic name: 3-bromo-2-hydroxypropanoic acid, C3H5BrO3) (II), and ß-iodolactic acid (systematic name: 2-hydroxy-3-iodopropanoic acid, C3H5IO3) (III). The number of molecules in the asymmetric unit of each crystal structure (Z') was found to be two for I and II, and one for III, making I and II isostructural and III unique. The difference between the molecules in the asymmetric units of I and II is due to the direction of the hydrogen bond of the alcohol group to a neighboring molecule. Molecular packing shows that each structure has alternating layers of intermolecular hydrogen bonding and halogen-halogen interactions. Hirshfeld surfaces and two-dimensional fingerprint plots were analyzed to further explore the intermolecular interactions of these structures. In I and II, energy minimization is achieved by lowering of the symmetry to adopt two independent molecular conformations in the asymmetric unit.


Asunto(s)
Enlace de Hidrógeno , Cristalografía por Rayos X , Conformación Molecular
18.
Transplantation ; 106(2): e126-e140, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34534191

RESUMEN

BACKGROUND: Hepatic ischemia-reperfusion injury (IRI) is an unavoidable outcome of liver transplantation, during which neutrophil extracellular traps (NETs) may play a critical role in the IRI-induced immune response to inflammation. The purpose of this study was to identify the function of recombinant human thrombomodulin (rTM) in the remission of hepatic IRI after liver transplantation and elucidate the specific mechanism. METHODS: NET formation (NETosis) was detected in the serum of liver transplantation patients and rats following liver transplantation. Hematoxylin-eosin staining, terminal deoxynucleotidyl transferase 2´-deoxyuridine, 5´-triphosphate nick-end labeling staining, immunohistochemistry, and immunofluorescence were used to assess the effect of rTM on NETosis in vitro and in vivo. RESULTS: We found that rTM markedly inhibited neutrophil formation in NETs, reduced apoptosis in hepatocytes, alleviated rat hepatic IRI, and improved liver function. In vitro, rTM inhibited neutrophil formation in NETs, and lipopolysaccharide (a Toll-like receptor 4 agonist) reversed the inhibitory effect of rTM on NETosisN. rTM blocked a Toll-like receptor 4 and the downstream extracellular signal-regulated kinase/c-Jun NH2 terminal kinase and nicotinamide adenine dinucleotide phosphate (NADPH)/reactive oxygen species/peptidylarginine deiminase 4 signaling pathways to protect against hepatic IRI and inhibit NETosis. In addition, we demonstrated that combined treatment with rTM and an NADPH oxidative inhibitor had a better effect than either treatment alone. CONCLUSIONS: NETs are a potential therapeutic target in hepatic IRI, and rTM could be used to prevent IR-induced hepatic injury. In addition, cotargeting NETosis-related signaling pathways might be a novel therapeutic strategy for hepatic IRI treatment.


Asunto(s)
Trampas Extracelulares , Trasplante de Hígado , Daño por Reperfusión , Animales , Humanos , Hígado/metabolismo , Trasplante de Hígado/efectos adversos , Ratas , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/etiología , Daño por Reperfusión/prevención & control , Trombomodulina/metabolismo , Receptor Toll-Like 4/metabolismo
20.
Exp Cell Res ; 406(1): 112719, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34273405

RESUMEN

Hepatic ischemia/reperfusion injury (IRI) is an adverse effect for liver transplantation which is characterized by immune response mediated inflammation. Recent studies report that neutrophil extracellular traps (NETs) are implicated in hepatic IRI. The aim of this study was to explore the mechanism of action of tetramethylpyrazine (TMP), the main chemical composition of Ligusticum chuanxiong in treatment of ischemic related diseases. Data showed that hepatic IRI increases the leak of alanine aminotransferase (ALT) and aspartate transaminase (AST), and stimulates formation of NETs. Extracellular DNA/NETs assay, hematoxylin-eosin (HE) staining, immunofluorescence assay, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) and Western blot assay, showed that TMP significantly reduces formation of NETs and alleviates hepatic IRI. Moreover, TMP and Diphenyleneiodonium (DPI) suppressed ROS production in neutrophils. In addition, analysis showed that activation of NADPH oxidase plays a role in formation of NETs triggered by hepatic IRI. Notably, TMP inhibited formation of NETs though inhibition of NADPH oxidase. Additionally, Combination treatment using TMP and DPI was more effective compared with monotherapy of either of the two drugs. These findings show that combination therapy using TMP and DPI is a promising method for treatment hepatic IRI.


Asunto(s)
Antioxidantes/farmacología , Trampas Extracelulares/efectos de los fármacos , Trasplante de Hígado/rehabilitación , Compuestos Onio/farmacología , Pirazinas/farmacología , Daño por Reperfusión/tratamiento farmacológico , Alanina Transaminasa/metabolismo , Animales , Aspartato Aminotransferasas/metabolismo , Ácidos Nucleicos Libres de Células/antagonistas & inhibidores , Ácidos Nucleicos Libres de Células/sangre , Modelos Animales de Enfermedad , Sinergismo Farmacológico , Quimioterapia Combinada/métodos , Trampas Extracelulares/metabolismo , Etiquetado Corte-Fin in Situ , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/cirugía , Trasplante de Hígado/métodos , Masculino , NADPH Oxidasas/antagonistas & inhibidores , NADPH Oxidasas/metabolismo , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Neutrófilos/patología , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Daño por Reperfusión/cirugía , Resultado del Tratamiento
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