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1.
Curr Microbiol ; 81(9): 283, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39066927

RESUMEN

A novel bacterium designated as SSA5.23T was isolated from seawater. Cells of SSA5.23T are Gram-stain-negative, short, rod-shaped, and exhibit motility via numerous peritrichous flagella. The strain could grow at temperatures ranging from 15 to 35 °C (optimum at 25 °C), in a salinity range of 0-5.0% (w/v) NaCl, and within a pH range of 6.0-9.0 (optimum at pH 7.0). The predominant cellular fatty acid of SSA5.23T was C18:1 ω7c/C18:1 ω6c, and the major respiratory quinones were Q-9 and Q-10. Diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol were identified as the primary polar lipids. The complete genome (5.47 Mb) of SSA5.23T comprises of a circular chromosome of 3.64 Mb and three plasmids, specifically sized at 59.73 kb, 227.82 kb, and 1.54 Mb, respectively. Certain genes located on the plasmids play roles in denitrification, oxidative stress resistance, and osmotic tolerance, which likely contribute to the adaptability of this strain in marine conditions. Core-proteome average amino acid identity analysis effectively identified the strain's affiliation with the genus Affinirhizobium, showing the highest value (89.9%) with Affinirhizobium pseudoryzae DSM 19479T. This classification was further supported by the phylogenetic analysis of concatenated alignment of 170 single-copy orthologous proteins. When compared to related reference strains, SSA5.23T displayed an average nucleotide identity ranging from 74.9 to 80.3% and digital DNA-DNA hybridization values ranging from 19.9 to 23.9%. Our findings confirmed that strain SSA5.23T represents a novel species of the genus Affinirhizobium, for which the name Affinirhizobium gouqiense sp. nov. (type strain SSA5.23T = LMG 32560T = MCCC 1K07165T) was suggested.


Asunto(s)
ADN Bacteriano , Ácidos Grasos , Genoma Bacteriano , Filogenia , Agua de Mar , Agua de Mar/microbiología , China , Ácidos Grasos/análisis , ADN Bacteriano/genética , Rhizobium/genética , Rhizobium/clasificación , Rhizobium/aislamiento & purificación , Composición de Base , Técnicas de Tipificación Bacteriana , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Islas , Genómica
2.
Food Funct ; 15(11): 5955-5971, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38738998

RESUMEN

The structural characteristics of fucoidans exhibit species and regional diversity. Previous studies have demonstrated that Laminaria japonica- and Ascophyllum nodosum-derived fucoidans have type I and type II fucosyl chains, respectively. These chemical differences may contribute to distinct hypolipidemic effects and mechanisms of action. Chemical analysis demonstrated that the percentage contents of sulfate, glucuronic acid, and galactose were higher in L. japonica-derived fucoidans than those of A. nodosum-derived fucoidans. In hyperlipidemic apolipoprotein E-deficient mice, both A. nodosum- and L. japonica-derived fucoidans significantly decreased the plasma and hepatic levels of total cholesterol and triglyceride, leading to the reduction of atherosclerotic plaques. Western blotting experiments demonstrated that these fucoidans significantly enhanced the expression and levels of scavenger receptor B type 1, cholesterol 7 alpha-hydroxylase A1, and peroxisome proliferator-activated receptor (PPAR)-α, contributing to circulating lipoprotein clearance and fatty acid degradation, respectively. Differentially, L. japonica-derived fucoidan significantly increased the LXR/ATP-binding cassette G8 signaling pathway in the small intestine, as revealed by real-time quantitative PCR, which may lead to further cholesterol and other lipid excretion. Collectively, these data are useful for understanding the hypolipidemic mechanisms of action of seaweed-derived fucoidans, and their potential application for the prevention and/or treatment of atherosclerotic cardiovascular diseases.


Asunto(s)
Apolipoproteínas E , Ascophyllum , Hipolipemiantes , Laminaria , Polisacáridos , Animales , Laminaria/química , Ascophyllum/química , Ratones , Polisacáridos/farmacología , Polisacáridos/química , Hipolipemiantes/farmacología , Apolipoproteínas E/genética , Masculino , Ratones Endogámicos C57BL , Triglicéridos/sangre , Triglicéridos/metabolismo , Colesterol/sangre , Colesterol/metabolismo , Ratones Noqueados , PPAR alfa/metabolismo , PPAR alfa/genética , Hiperlipidemias/tratamiento farmacológico , Hiperlipidemias/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/química , Hígado/metabolismo , Hígado/efectos de los fármacos , Humanos , Algas Comestibles
3.
J Am Chem Soc ; 146(18): 12485-12495, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38651836

RESUMEN

Understanding the mechanisms of C-H activation of alkanes is a very important research topic. The reactions of metal clusters with alkanes have been extensively studied to reveal the electronic features governing C-H activation, while the experimental cluster reactivity was qualitatively interpreted case by case in the literature. Herein, we prepared and mass-selected over 100 rhodium-based clusters (RhxVyOz- and RhxCoyOz-) to react with light alkanes, enabling the determination of reaction rate constants spanning six orders of magnitude. A satisfactory model being able to quantitatively describe the rate data in terms of multiple cluster electronic features (average electron occupancy of valence s orbitals, the minimum natural charge on the metal atom, cluster polarizability, and energy gap involved in the agostic interaction) has been constructed through a machine learning approach. This study demonstrates that the general mechanisms governing the very important process of C-H activation by diverse metal centers can be discovered by interpreting experimental data with artificial intelligence.

4.
Heliyon ; 10(6): e28086, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38533007

RESUMEN

Wound healing is an intricate and fine regulatory process. In diabetic patients, advanced glycation end products (AGEs), excessive reactive oxygen species (ROS), biofilm formation, persistent inflammation, and angiogenesis regression contribute to delayed wound healing. Epigenetics, the fast-moving science in the 21st century, has been up to date and associated with diabetic wound repair. In this review, we go over the functions of epigenetics in diabetic wound repair in retrospect, covering transcriptional and posttranscriptional regulation. Among these, we found that histone modification is widely involved in inflammation and angiogenesis by affecting macrophages and endothelial cells. DNA methylation is involved in factors regulation in wound repair but also affects the differentiation phenotype of cells in hyperglycemia. In addition, noncodingRNA regulation and RNA modification in diabetic wound repair were also generalized. The future prospects for epigenetic applications are discussed in the end. In conclusion, the study suggests that epigenetics is an integral regulatory mechanism in diabetic wound healing.

5.
Int J Biol Macromol ; 258(Pt 1): 128104, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37977460

RESUMEN

In biological control programs, knowledge about diapause regulation in natural enemy insects provides important insight for improving long-term storage, transportation, and field adoption of these biological control agents. As a natural predator of agricultural pests, the lady beetle Coccinella septempunctata has been commercially mass-cultured and widely employed in pest management. In some insects, insulin signaling, in conjunction with the downstream transcription factor Forkhead box O (FoxO), are master regulators of multiple physiological processes involved in diapause, but it is unclear whether insulin signaling and FoxO affect the diapause of C. septempunctata. In this study, we use a combination of approaches to demonstrate that insulin signaling and FoxO mediate the diapause response in C. septempunctata. In diapausing beetles, application of exogenous insulin and knocking down expression of CsFoxo with RNA interference (RNAi) both rescued beetles from developmental arrest. In non-diapausing beetles, knocking down expression of the insulin receptor (CsInR) with RNA interference (RNAi) arrested ovarian development and decreased juvenile hormone (JH) content to levels comparable to the diapause state. Taken together, these results suggest that a shutdown of insulin signaling prompts the activation of the downstream FoxO gene, leading to the diapause phenotype.


Asunto(s)
Escarabajos , Diapausa , Humanos , Animales , Escarabajos/genética , Insulina/metabolismo , Factores de Transcripción Forkhead/metabolismo , Transducción de Señal
6.
J Phys Chem Lett ; 14(28): 6431-6436, 2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37432842

RESUMEN

The introduction of organic ligands is one of the effective strategies to improve the stability and reactivity of metal clusters. Herein, the enhanced reactivity of benzene-ligated cluster anions Fe2VC(C6H6)- with respect to naked Fe2VC- is identified. Structural characterization suggests that C6H6 is molecularly bound to the dual metal site in Fe2VC(C6H6)-. Mechanistic details reveal that the cleavage of N≡N is feasible in Fe2VC(C6H6)-/N2 but hindered by an overall positive barrier in the Fe2VC-/N2 system. Further analysis discloses that the ligated C6H6 regulates the compositions and energy levels of the active orbitals of the metal clusters. More importantly, C6H6 serves as an electron reservoir for the reduction of N2 to lower the crucial energy barrier of N≡N splitting. This work demonstrates that the flexibility of C6H6 in terms of withdrawing and donating electrons is crucial to regulating the electronic structures of the metal cluster and enhancing the reactivity.

7.
Chin Med ; 18(1): 65, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37264387

RESUMEN

BACKGROUND: Baphicacanthis Cusiae Rhizoma et Radix, commonly known as Nan-Ban-Lan-Gen (NBLG), is an essential traditional Chinese medicine that possesses diverse bioactivities, particularly noteworthy for its antiviral properties. Although NBLG has been listed in the Chinese Pharmacopoeia as an independent Chinese medicine, the establishment of a comprehensive quality standard for NBLG remains elusive. The absence of assay for marker compound in its quality standards has led to the lack of corresponding quality control measures for NBLG-containing preparations, and its discrimination from adulterant species in the market which thereby can significantly impact the efficacy and safety of NBLG-containing products. METHODS: Ultra-high performance liquid chromatography (UHPLC) coupled with quadrupole-time-of-flight mass spectrometry (Q-TOF-MS) was employed for comprehensive profiling of the chemical constituents of NBLG, the stem of Baphicacanthus cusia (Nees) Bremek (NBLJ), and the roots of Isatis indigotica Fort. (Bei-Ban-Lan-Gen, BBLG). Additionally, multivariate analysis was conducted to compare the chemical components of NBLG with those of NBLJ and BBLG. Furthermore, we established an optimized and validated HPLC method to obtain the fingerprint of NBLG and quantify the content of 2-benzoxazolinone and acteoside in the samples. RESULTS: A total of 73 compounds belonging to six classes were assigned in NBLG, with alkaloids being the most abundant and diverse species. High compositional similarities with significant differences in content were observed between NBLG and NBLJ. Moreover, the chemical profile of BBLG markedly differed from that of NBLG. An informative high performance liquid chromatography (HPLC) fingerprint of NBLG comprising seven characteristic peaks that can be used for quality assessment was established. Notably, we propose a quality control standard for NBLG, stipulating that the limit of content in dry weight for both 2-benzoxazolinone and acteoside should not be less than 0.010%. CONCLUSION: This study provides the most comprehensive chemical information to date on NBLG, offering valuable insights into its authentication and quality control. Our findings highlight the importance of comprehensive chemical profiling to differentiate potential substitutions and adulterations of herbal medicines, particularly when the original source is scarce or unavailable. These results can aid in the development of quality control measures for NBLG-containing preparations, ensuring their safety and efficacy.

8.
J Pharm Anal ; 13(11): 1309-1325, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38174113

RESUMEN

The canonical transient receptor potential channel (TRPC) proteins form Ca2+-permeable cation channels that are involved in various heart diseases. However, the roles of specific TRPC proteins in myocardial ischemia/reperfusion (I/R) injury remain poorly understood. We observed that TRPC1 and TRPC6 were highly expressed in the area at risk (AAR) in a coronary artery ligation induced I/R model. Trpc1-/- mice exhibited improved cardiac function, lower serum Troponin T and serum creatine kinase level, smaller infarct volume, less fibrotic scars, and fewer apoptotic cells after myocardial-I/R than wild-type or Trpc6-/- mice. Cardiomyocyte-specific knockdown of Trpc1 using adeno-associated virus 9 mitigated myocardial I/R injury. Furthermore, Trpc1 deficiency protected adult mouse ventricular myocytes (AMVMs) and HL-1 cells from death during hypoxia/reoxygenation (H/R) injury. RNA-sequencing-based transcriptome analysis revealed differential expression of genes related to reactive oxygen species (ROS) generation in Trpc1-/- cardiomyocytes. Among these genes, oxoglutarate dehydrogenase-like (Ogdhl) was markedly downregulated. Moreover, Trpc1 deficiency impaired the calcineurin (CaN)/nuclear factor-kappa B (NF-κB) signaling pathway in AMVMs. Suppression of this pathway inhibited Ogdhl upregulation and ROS generation in HL-1 cells under H/R conditions. Chromatin immunoprecipitation assays confirmed NF-κB binding to the Ogdhl promoter. The cardioprotective effect of Trpc1 deficiency was canceled out by overexpression of NF-κB and Ogdhl in cardiomyocytes. In conclusion, our findings reveal that TRPC1 is upregulated in the AAR following myocardial I/R, leading to increased Ca2+ influx into associated cardiomyocytes. Subsequently, this upregulates Ogdhl expression through the CaN/NF-κB signaling pathway, ultimately exacerbating ROS production and aggravating myocardial I/R injury.

9.
Nat Commun ; 13(1): 7455, 2022 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-36460692

RESUMEN

Intracellular Ca2+ dysregulation is a key marker in septic cardiac dysfunction; however, regulation of the classic Ca2+ regulatory modules cannot successfully abolish this symptom. Here we show that the knockout of transient receptor potential canonical (TRPC) channel isoforms TRPC1 and TRPC6 can ameliorate LPS-challenged heart failure and prolong survival in mice. The LPS-triggered Ca2+ release from the endoplasmic reticulum both in cardiomyocytes and macrophages is significantly inhibited by Trpc1 or Trpc6 knockout. Meanwhile, TRPC's molecular partner - calmodulin - is uncoupled during Trpc1 or Trpc6 deficiency and binds to TLR4's Pococurante site and atypical isoleucine-glutamine-like motif to block the inflammation cascade. Blocking the C-terminal CaM/IP3R binding domain in TRPC with chemical inhibitor could obstruct the Ca2+ leak and TLR4-mediated inflammation burst, demonstrating a cardioprotective effect in endotoxemia and polymicrobial sepsis. Our findings provide insight into the pathogenesis of endotoxemic cardiac dysfunction and suggest a novel approach for its treatment.


Asunto(s)
Traumatismos Craneocerebrales , Endotoxemia , Insuficiencia Cardíaca , Canales de Potencial de Receptor Transitorio , Animales , Ratones , Endotoxemia/complicaciones , Canal Catiónico TRPC6 , Lipopolisacáridos/toxicidad , Receptor Toll-Like 4 , Inflamación
10.
Front Plant Sci ; 13: 832177, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35310672

RESUMEN

Plants overcome the changing environmental conditions through diverse strategies and complex regulations. In addition to direct regulation of gene transcription, alternative splicing (AS) also acts as a crucial regulatory mechanism to cope with various stresses. Generating from the same pre-mRNA, AS events allow rapid adjustment of the abundance and function of key stress-response components. Mounting evidence has indicated the close link between AS and plant stress response. However, the mechanisms on how environmental stresses trigger AS are far from understood. The advancing high-throughput sequencing technologies have been providing useful information, whereas genetic approaches have also yielded remarkable phenotypic evidence for AS control of stress responses. It is important to study how stresses trigger AS events for both fundamental science and applications. We review current understanding of stress-responsive AS in plants and discuss research challenges for the near future, including regulation of splicing factors, epigenetic modifications, the shared targets of splice isoforms, and the stress-adjusting ratios between splicing variants.

11.
Polymers (Basel) ; 14(5)2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35267675

RESUMEN

Application of porous polymeric materials is severely limited by their ultralow thermal conductivities. Herein, by promoting the formation of thermal conduction pathways, we fabricated open-cellular structured polyethylene/hexagonal boron nitride hybrid thermal conductors via melt compounding plus salt leaching. The structural analyses indicate that the inclusion of hBN can enhance the open-cell level of resultant materials. X-ray diffractions confirm the high in-plane alignments of hBN in each sample. Consequently, the test results evidence the superior thermal conductivities of our samples, and the thermal conductivities of each sample are characterized as functions of hBN loadings. Ultimately, our advanced porous thermal conductor with a low hBN loading of 3.1 vol% exhibits a high specific thermal conductivity of 0.75 (W/mk)/(g/cm3), which is 82.9% higher than virgin PE and far higher than bulk PE/hBN composites. Our work also intends to reveal the architectural advantages of open-cellular, as compared with the close-one, in fabricating porous materials with highly interconnected fillers.

12.
Acupunct Med ; 40(4): 360-368, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35034504

RESUMEN

BACKGROUND AND AIM: Disordered hepatic energy metabolism is found in obese rats with insulin resistance (IR). There are insufficient experimental studies of electroacupuncture (EA) for IR and type 2 diabetes mellitus (T2DM). The aim of this study was to probe the effect of EA on disordered hepatic energy metabolism and the adenosine monophosphate (AMP)-activated protein kinase (AMPK)/mammalian target of rapamycin complex 1 (mTORC1)/ribosomal protein S6 kinase, 70-kDa (p70S6K) signaling pathway. METHODS: Zucker Diabetic Fatty (ZDF) rats were randomly divided into three groups: EA group receiving EA treatment; Pi group receiving pioglitazone gavage; and ZF group remaining untreated (n = 8 per group). Inbred non-insulin-resistant Zucker lean rats formed an (untreated) healthy control group (ZL, n = 8). Fasting plasma glucose (FPG), fasting insulin (FINS), C-peptide, C-reactive protein (CRP) and homeostatic model assessment of insulin resistance (HOMA-IR) indices were measured. Hematoxylin-eosin (H&E) staining was used to investigate the liver morphologically. The mitochondrial structure of hepatocytes was observed by transmission electron microscopy (TEM). Western blotting was adopted to determine protein expression of insulin receptor substrate 1 (IRS-1), mTOR, mTORC1, AMPK, tuberous sclerosis 2 (TSC2) and p70S6K, and their phosphorylation. RT-PCR was used to quantify IRS-1, mTOR, mTORC1, AMPK and p70S6K mRNA levels. RESULTS: Compared with the ZF group, FPG, FINS, C-peptide, CRP and HOMA-IR levels were significantly reduced in the EA group (p < 0.05, p < 0.01). Evaluation of histopathology showed improvement in liver appearances following EA. Phosphorylation levels of AMPK, mTOR and TSC2 decreased, and IRS-1 and p70S6K increased, in hepatocytes of the ZF group, while these negative effects appeared to be alleviated by EA. CONCLUSIONS: EA can effectively ameliorate IR and regulate energy metabolism in the ZDF rat model. AMPK/mTORC1/p70S6K and related molecules may represent a potential mechanism of action underlying these effects.


Asunto(s)
Diabetes Mellitus Tipo 2 , Electroacupuntura , Resistencia a la Insulina , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Péptido C/metabolismo , Péptido C/farmacología , Diabetes Mellitus Tipo 2/terapia , Metabolismo Energético , Insulina/metabolismo , Mamíferos/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Ratas , Ratas Zucker , Proteínas Quinasas S6 Ribosómicas 70-kDa/genética , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Proteínas Quinasas S6 Ribosómicas 70-kDa/farmacología , Transducción de Señal , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/farmacología
13.
Antonie Van Leeuwenhoek ; 115(1): 33-40, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34743249

RESUMEN

A Gram-stain-negative, wheat, rod-shaped, non-motile, non-spore forming, and facultatively anaerobic bacterium strain, designated as PIT, was isolated from saline silt samples collected in saltern in Yantai, Shandong, China. Growth was observed within the ranges 4-45 °C (optimally at 33 °C), pH 6.0-9.0 (optimally at pH 7.0) and 1.0-11.0% NaCl (optimally at 3.0%, w/v). Strain PIT showed highest 16S rRNA gene sequence similarity to Kangiella sediminilitoris BB-Mw22T (98.3%) and Kangiella taiwanensis KT1T (98.3%). The major cellular fatty acids (> 10% of the total fatty acids) were iso-C15:0 (52.7%) and summed featured 9 (iso-C17:1ω9c/C16:0 10-methyl, 11.8%). The major polar lipids identified were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine and phosphatidylglycerol. The major respiratory isoprenoid quinone was Q-8. The G + C content of the genomic DNA was 45.8%. Average Nucleotide Identity values between whole genome sequences of strain PIT and next related type strains supported the novel species status. Based on physiological, biochemical, chemotaxonomic characteristics and genomic analysis, strain PIT is considered to represent a novel species within the genus Kangiella, for which the name Kangiella shandongensis sp. nov. is proposed. The type strain is PIT (= KCTC 82509 T = MCCC 1K04352T).


Asunto(s)
ARN Ribosómico 16S , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
14.
Cell Death Differ ; 29(4): 709-721, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34621049

RESUMEN

A limited delivery of oxygen and metabolic substrate to the heart caused by myocardial infarction (MI) impairs the cardiac function, and often results in heart failure. Here, we identified a circRNA (circ-SNRK) from SNRK (sucrose nonfermenting 1-related kinase, which can increase the cardiac mitochondrial efficiency) in cardiomyocytes (CMs). Circ-SNRK can sponge the miR-33 and in turn improved the ATP synthesis via SNRK, proving the existence of circ-SNRK - miR-33 - SNRK axis. Furthermore, we found that protein NOVA1 (NOVA alternative splicing regulator 1) could accelerate the circ-SNRK formation; a cleaved peptide (~55 kDa) from SNRK enters the nucleus and blocks the cyclization of circ-SNRK via binding to NOVA1. The aforementioned negative feedback of SNRK to circ-SNRK limited the SNRK at a proper level, and inhibited the protective role of circ-SNRK in ischemic heart. In addition, our in vivo experiment indicated that the overexpression of exogenic circ-SNRK could break this loop and improves the cardiac function post-MI in rats. Together, our results demonstrated that the negative loop of circ-SNRK with SNRK regulates the energy metabolism in CMs, thus might be a potential therapeutic target for heart failure.


Asunto(s)
Insuficiencia Cardíaca , MicroARNs , Infarto del Miocardio , Proteínas Serina-Treonina Quinasas , ARN Circular , Animales , Retroalimentación , Insuficiencia Cardíaca/metabolismo , MicroARNs/genética , Infarto del Miocardio/genética , Infarto del Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Antígeno Ventral Neuro-Oncológico , Proteínas Serina-Treonina Quinasas/genética , ARN Circular/genética , Proteínas de Unión al ARN/metabolismo , Ratas
15.
Zhongguo Zhong Yao Za Zhi ; 46(23): 6224-6230, 2021 Dec.
Artículo en Chino | MEDLINE | ID: mdl-34951249

RESUMEN

Alzheimer's disease(AD) patients in China have been surging, and the resultant medical burden and care demand have a huge impact on the development of individuals, families, and the society. The active component compound of Epimedii Folium, Astragali Radix, and Puerariae Lobatae Radix(YHG) can regulate the expression of iron metabolism-related proteins to inhibit brain iron overload and relieve hypofunction of central nervous system in AD patients. Hepcidin is an important target regulating iron metabolism. This study investigated the effect of YHG on the expression of a disintegrin and metalloprotease-17(ADAM17), a key enzyme in the hydrolysis of ß amyloid precursor protein(APP) in HT22 cells, by mediating hepcidin. To be specific, HT22 cells were cultured in vitro, followed by liposome-mediated siRNA transfection to silence the expression of hepcidin. Real-time PCR and Western blot were performed to examine the silencing result and the effect of YHG on hepcidin in AD cell model. HT22 cells were randomized into 7 groups: control group, Aß25-35 induction(Aß) group, hepcidin-siRNA(siRNA) group, Aß25-35 + hepcidin-siRNA(Aß + siRNA) group, Aß25-35+YHG(Aß+YHG) group, hepcidin-siRNA+YHG(siRNA+YHG) group, Aß25-35+hepcidin-siRNA+YHG(Aß+siRNA+YHG) group. The expression of ADAM17 mRNA in cells was detected by real-time PCR, and the expression of ADAM17 protein by immunofluorescence and Western blot. Immunofluorescence showed that the ADAM17 protein expression was lower in the Aß group, siRNA group, and Aß+siRNA group than in the control group(P<0.05) and the expression was lower in the Aß+siRNA group(P<0.05) and higher in the Aß+YHG group(P<0.05) than in the Aß group. Moreover, the ADAM17 protein expression was lower in the Aß+siRNA group(P<0.05) and higher in the siRNA+YHG group(P< 0.05) than in the siRNA group. The expression was higher in the Aß+siRNA+YHG group than in the Aß+siRNA group(P<0.05). The results of Western blot and real-time PCR were consistent with those of immunofluorescence. The experiment showed that YHG induced hepcidin to up-regulate the expression of ADAM17 in AD cell model and promote the activation of non-starch metabolic pathways, which might be the internal mechanism of YHG in preventing and treating AD.


Asunto(s)
Enfermedad de Alzheimer , Medicamentos Herbarios Chinos , Pueraria , Proteína ADAM17 , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides , Medicamentos Herbarios Chinos/farmacología , Hepcidinas/genética , Humanos
16.
Mar Drugs ; 19(11)2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34822499

RESUMEN

Alginate, the most abundant polysaccharides of brown algae, consists of various proportions of uronic acid epimers α-L-guluronic acid (G) and ß-D-mannuronic acid (M). Alginate oligosaccharides (AOs), the degradation products of alginates, exhibit excellent bioactivities and a great potential for broad applications in pharmaceutical fields. Alginate lyases can degrade alginate to functional AOs with unsaturated bonds or monosaccharides, which can facilitate the biorefinery of brown algae. On account of the increasing applications of AOs and biorefinery of brown algae, there is a scientific need to explore the important aspects of alginate lyase, such as catalytic mechanism, structure, and property. This review covers fundamental aspects and recent developments in basic information, structural characteristics, the structure-substrate specificity or catalytic efficiency relationship, property, molecular modification, and applications. To meet the needs of biorefinery systems of a broad array of biochemical products, alginate lyases with special properties, such as salt-activated, wide pH adaptation range, and cold adaptation are outlined. Withal, various challenges in alginate lyase research are traced out, and future directions, specifically on the molecular biology part of alginate lyases, are delineated to further widen the horizon of these exceptional alginate lyases.


Asunto(s)
Alginatos/farmacología , Phaeophyceae , Polisacáridos/farmacología , Alginatos/química , Animales , Organismos Acuáticos , Humanos , Polisacáridos/química , Relación Estructura-Actividad , Especificidad por Sustrato
17.
Phytother Res ; 35(7): 3898-3915, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33860590

RESUMEN

Isoliquiritigenin (ISO) is a flavonoid extracted from the root of licorice, which serves various biological and pharmacological functions including antiinflammatory, antioxidation, liver protection, and heart protection. However, the mechanism of its action remains elusive and the direct target proteins of ISO have not been identified so far. Through cell-based screening, we identified ISO as a potent lipid-lowering compound. ISO treatment successfully ameliorated fatty acid-induced cellular lipid accumulation and improved nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) by increasing PPARα-dependent lipid oxidation and decreasing SREBPs-dependent lipid synthesis. Both these signaling required the activation of SIRT1. Knockdown of SIRT1 resulted in the reversal of ISO beneficiary effects suggesting that the lipid-lowering activity of ISO was regulated by SIRT1 expression. To identify the direct target of ISO, limited proteolysis combined with mass spectrometry (LiP-SMap) strategy was applied and IQGAP2 was identified as the direct target for ISO in regulating lipid homeostasis. In the presence of ISO, both mRNA and protein levels of SIRT1 were increased; however, this effect was abolished by blocking IQGAP2 expression using siRNA. To explore how IQGAP2 regulated the expression level of SIRT1, proteome profiler human phospho-kinase array kit was used to reveal possible phosphorylated kinases and signaling nodes that ISO affected. We found that through phosphorylation of CREB, ISO transduced signals from IQGAP2 to upregulate SIRT1 expression. Thus, we not only demonstrated the molecular basis of ISO in regulating lipid metabolism but also exhibited for the first time a novel IQGAP2-CREB-SIRT1 axis in treating NAFLD/NASH.


Asunto(s)
Chalconas , Enfermedad del Hígado Graso no Alcohólico , Animales , Chalconas/farmacología , Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Metabolismo de los Lípidos , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Sirtuina 1/metabolismo , Proteínas Activadoras de ras GTPasa/metabolismo
18.
Infect Dis Ther ; 10(1): 281-290, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33146854

RESUMEN

INTRODUCTION: Sepsis is a complication in acute-on-chronic liver failure (ACLF) patients associated with high rates of mortality and morbidity. Early diagnosis of sepsis in ACLF patients can improve prognosis. This study aimed to explore potential effective biomarkers for the early diagnosis of sepsis in ACLF patients. METHODS: Ninety-four ACLF patients with sepsis were enrolled from 10 hospitals across China from January 2015 to June 2016 as well as 49 ACLF patients without infection from Xiangya Hospital. The first-day admission data and SOFA score and CLIF-SOFA score were collected. The differences of indicators between groups were compared with Kruskal-Wallis test. The receiver-operating characteristic (ROC) curve was analyzed to evaluate the diagnostic efficiency of the selected factors. RESULTS: Soluble triggering receptor expressed on myeloid cell-1 (sTREM-1) and presepsin were significantly higher in ACLF-sepsis patients compared with ACLF patients with no infection (P < 0.001). sTREM-1 and presepsin presented higher diagnostic value in sepsis for ACLF patients compared with other biomarkers [white blood cells (WBC), procalcitonin (PCT) and C-reactive protein (CRP)]. Combining sTREM-1 or presepsin with the CLIF-SOFA score increased the diagnostic efficiency (AUC = 0.876 or AUC = 0.913, respectively). CONCLUSIONS: sTREM-1 and presepsin are potential biomarkers for the early diagnosis of sepsis in ACLF patients. The combination of presepsin and the CLIF-SOFA score is a promising method for diagnosing sepsis in ACLF patients. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT02457637.

19.
Int J Biol Macromol ; 161: 1346-1357, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32784023

RESUMEN

In this study, two homogeneous polysaccharides (PFC-1 and PFC-2) having anti-atherosclerotic activity were isolated from Fructus Corni. PFC-1 and PFC-2 were 1,6-α-glucans with the molecular weight of 4.4 kDa and 82.0 kDa, respectively. In the in vitro experiments, PFC-1 and PFC-2 showed significant inhibitory effects on the cholesterol accumulation in RAW264.7 macrophages induced by oxidized low-density lipoproteins (ox-LDL), and the inhibitory rate of PFC-2 was 81.62%. Apolipoprotein E-deficient (ApoE-/-) mice fed high-fat diet (HFD) were used to evaluate the anti-atherosclerotic effects of PFC-2 in vivo. The aortic root lipid area decreased by 55.01% in the PFC-2-administered group as compared to the model group. PFC-2 decreased the levels of serum low-density lipoprotein cholesterol, total cholesterol, triglycerides, and malondialdehyde, increased the superoxide dismutase activity, and reduced the contents of lipid and macrophages in the aortic sinus plaque in ApoE-/- mice fed with HFD. Furthermore, PFC-2 markedly inhibited the expression of type A1 scavenger receptor (SR-A1) and cluster of differentiation 36 (CD36) in ox-LDL-treated macrophages. Taken together, 1,6-α-glucans from Fructus Corni showed significant anti-atherogenic effect, and the mechanism is related to enhanced antioxidant activity of the ApoE-/- mice and down-regulated the expression of SR-A1 and CD36 proteins in macrophages.


Asunto(s)
Cornus/química , Glucanos/química , Glucanos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Animales , Apolipoproteínas E/genética , Aterosclerosis/tratamiento farmacológico , Biomarcadores , Supervivencia Celular/efectos de los fármacos , Colesterol/sangre , Modelos Animales de Enfermedad , Células Espumosas/efectos de los fármacos , Células Espumosas/metabolismo , Células Espumosas/patología , Glucanos/aislamiento & purificación , Inmunohistoquímica , Lipoproteínas LDL , Espectroscopía de Resonancia Magnética , Metilación , Ratones , Ratones Noqueados , Peso Molecular , Monosacáridos/química , Extractos Vegetales/aislamiento & purificación , Placa Aterosclerótica/tratamiento farmacológico , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patología , Células RAW 264.7 , Análisis Espectral , Relación Estructura-Actividad
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