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2.
Zhongguo Zhen Jiu ; 44(4): 441-448, 2024 Apr 12.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-38621732

RESUMEN

OBJECTIVES: To observe the effects of electroacupuncture (EA) with "intestinal disease prescription" on the intestinal mucosal barrier and NLRP3 inflammasome in rats with dextran sulfate sodium (DSS)-induced acute ulcerative colitis (UC), and explore the underlying mechanism of EA with "intestinal disease prescription" for the treatment of UC. METHODS: Thirty-two healthy male SPF-grade SD rats were randomly divided into a blank group, a model group, a medication group, and an EA group, with 8 rats in each group. Except for the blank group, the UC model was established by administering 5% DSS solution for 7 days. After modeling, the rats in the medication group were treated with mesalazine suspension (200 mg/kg) by gavage, while the rats in the EA group were treated with acupuncture at bilateral "Tianshu" (ST 25), "Shangjuxu" (ST 37) and "Zhongwan" (CV 12), with the ipsilateral "Tianshu" (ST 25) and "Shangjuxu" (ST 37) connected to the electrodes of the EA instrument, using disperse-dense wave, with a frequency of 10 Hz/50 Hz, and each intervention lasted for 20 minutes. Both interventions were performed once daily for 3 days. The general conditions of rats were observed daily. After intervention, the disease activity index (DAI) score was calculated; colon tissue morphology was observed using HE staining; serum levels of pro-inflammatory cytokines (interleukin [IL]-18, IL-1ß) were measured by ELISA; protein expression of NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), and Caspase-1 in colon tissues was detected by Western blot; positive expression of zonula occludens-1 (ZO-1) and Occludin in colon tissues was examined by immunofluorescence. RESULTS: Compared with the blank group, the rats in the model group exhibited poor general conditions, slow body weight gain, shortened colon length (P<0.01), increased DAI score and spleen index (P<0.01), elevated serum IL-18 and IL-1ß levels, and increased protein expression of NLRP3, ASC, and Caspase-1 in colon tissues (P<0.01), along with decreased positive expression of ZO-1 and Occludin in colon tissues (P<0.01). Compared with the model group, the rats in the medication group and the EA group exhibited improved general conditions, accelerated body weight gain, increased colon length (P<0.05), reduced DAI scores and spleen indexes (P<0.05), decreased serum IL-18 and IL-1ß levels, and lower protein expression of NLRP3, ASC and Caspase-1 in colon tissues (P<0.05), as well as increased positive expression of ZO-1 and Occludin in colon tissues (P<0.05). There were no significant differences in the above indexes between the medication group and the EA group (P>0.05). Compared with the blank group, the rats in the model group exhibited disrupted colon mucosal morphology, disordered gland arrangement, and atrophy of crypts, along with significant inflammatory cell infiltration. Compared with the model group, the rats in both the medication group and the EA group showed relatively intact colon mucosal morphology, with restored and improved gland and crypt structures, and reduced inflammatory cell infiltration. CONCLUSIONS: EA with "intestinal disease prescription" has a significant therapeutic effect on DSS-induced UC, possibly by regulating the expression of NLRP3 inflammasome and proteins related to the intestinal mucosal barrier, thereby alleviating symptoms of ulcerative colitis.


Asunto(s)
Colitis Ulcerosa , Electroacupuntura , Ratas , Masculino , Animales , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/terapia , Inflamasomas/efectos adversos , Interleucina-18 , Ratas Sprague-Dawley , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Ocludina , Peso Corporal , Caspasas/efectos adversos
3.
Heliyon ; 10(2): e24632, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38293442

RESUMEN

Due to the uniqueness and interactivity of its scenario, the cultural and tourism commercial space consistently enriches and enhances the user experience while satisfying users' consumption and shopping. However, there is limited research on the participatory aspect of cultural tourism business spaces from the perspective of users. To this end, the present study investigates the participatory experience of cultural tourism commercial spaces by selecting 305 tourists who visited Huaihai Street in Suzhou for consumption and entertainment and quantifies the relationship between the public's flow experience, aesthetic judgments, and behavioral outcomes using a structural equation modeling approach. The results of the study confirm that aesthetic judgments and flow experiences positively impact behavioral outcomes and that flow experiences also affect aesthetic judgments and behavioral outcomes. These findings contribute to a better understanding of the significance of user participation in cultural tourism business spaces.

4.
Pharmaceutics ; 16(1)2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38258099

RESUMEN

Clinical drug administration aims to deliver drugs efficiently and safely to target tissues, organs, and cells, with the objective of enabling their therapeutic effects. Currently, the main approach to enhance a drug's effectiveness is ensuring its efficient delivery to the intended site. Due to the fact that there are still various drawbacks of traditional drug delivery methods, such as high toxicity and side effects, insufficient drug specificity, poor targeting, and poor pharmacokinetic performance, nanocarriers have emerged as a promising alternative. Nanocarriers possess significant advantages in drug delivery due to their size tunability and surface modifiability. Moreover, nano-drug delivery systems have demonstrated strong potential in terms of prolonging drug circulation time, improving bioavailability, increasing drug retention at the tumor site, decreasing drug resistance, as well as reducing the undesirable side effects of anticancer drugs. Numerous studies have focused on utilizing polysaccharides as nanodelivery carriers, developing delivery systems based on polysaccharides, or exploiting polysaccharides as tumor-targeting ligands to enhance the precision of nanoparticle delivery. These types of investigations have become commonplace in the academic literature. This review aims to elucidate the preparation methods and principles of polysaccharide gold nanocarriers. It also provides an overview of the factors that affect the loading of polysaccharide gold nanocarriers with different kinds of drugs. Additionally, it outlines the strategies employed by polysaccharide gold nanocarriers to improve the delivery efficiency of various drugs. The objective is to provide a reference for further development of research on polysaccharide gold nanodelivery systems.

5.
Autophagy ; 20(3): 701-703, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37934826

RESUMEN

Macroautophagy/autophagy receptors target their substrates to phagophores for subsequent sequestration within autophagosomes. During phagophore membrane expansion in mammalian cells, autophagy receptors simultaneously interact with the ubiquitinated substrates and the LC3/GABARAP proteins on the expanding membrane. In this punctum, we summarize and discuss our recent research progress on synthetic autophagy receptors (AceTACs). The series of AceTACs were designed by engineering the essential interacting domains and motifs of SQSTM1/p62 (sequestosome 1), a major mammalian autophagy receptor. Particularly, we replaced the ubiquitin-associated domain of SQSTM1 with a target-specific antibody, redirecting the bifunctional interactions of wild-type SQSTM1 and directing the degradation target into the autophagy process. We successfully demonstrated the targeted degradation of aggregation-prone proteins using the AceTAC degraders. Moreover, we presented a model system with a guideline to induce targeted degradation of organelles through the autophagy machinery.


Asunto(s)
Autofagia , Proteínas , Animales , Autofagia/fisiología , Proteína Sequestosoma-1/metabolismo , Proteínas/metabolismo , Autofagosomas/metabolismo , Ubiquitina/metabolismo , Proteínas Portadoras/metabolismo , Mamíferos/metabolismo
6.
Mol Neurobiol ; 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37976026

RESUMEN

To study the protective mechanism of acupuncture at "Jiangya Recipe" on chronic ischemic white matter injury in spontaneously hypertensive rats (SHR) and the regulation of Jun N-terminal kinase-N-methyl-D-aspartate receptor (JNK-NMDAR) loop. A hypertensive white matter injury model was established in 46 male SHR rats aged 11 weeks by bilateral common carotid artery tapering (SHR-2VGO). In the SHR sham operation group, only bilateral common carotid arteries were isolated and in the SHR-2VGO modeling group, 36 rats were used for microcoil spring clip implantation to narrow the common carotid arteries and then, after 2 weeks of modeling, rats with impaired motor function were removed, and SHR-2VGO rats with successful final models were randomly divided into the model group, JNK blocking group, and acupuncture group. The sham operation group, model group, and JNK blocking group underwent the same grasping fixation, and the acupuncture group received acupuncture at acupoints "Jiangya Fang" once daily. In the JNK blocker group, an injection cannula was implanted into the lateral ventricle and sp600125 was injected into the lateral ventricle at 4.5 ul/day for 4 weeks. One week after the end of the intervention, white matter lesions were detected by MRI DWI and T2 imaging, and the learning and memory ability of rats was tested by Y-Maze and Passive Avoidance. Myelin density was detected by luxol fast blue (LFB) staining, also axon arrangement, myelin integrity, and thickness of neurons were detected by electron microscopy; neuronal morphology and the number of Nissl bodies in the hippocampus were detected by Nissl staining, dendritic spine density changes were detected by Golgi staining, and JNK, NMDAR1, and N-methyl-D-receptor 2B (NMDAR2B) in DG, CA3 region of hippocampus were detected by immunohistochemistry, protein expression of p-JNK/JNK, p-NMDAR1/NMDAR1, NMDAR2B, GSK3ß protein expression in the fimbria of hippocampus was detected by Western blot. The Y maze test of SHR-2VGO+Acu and SHR-2VGO+ sp600125 group showed that the spontaneous alternating reaction rate increased significantly. At the same time, the incubation period increased significantly and the number of errors decreased significantly in Passive Avoidance. MRI T2WI showed that the white matter high signal of the corpus callosum, internal capsule and hippocampal fimbria in the SHR-2VGO+ sp600125 and SHR-2VGO+Acu groups was significantly lower than that in the SHR-2VGO model group, and the striatum and anterior commissure were not obvious. DWI showed that the SHR-2VGO model group had scattered high signal and limited diffusion movement in both the internal capsule and striatum, but the difference between groups was not obvious. Compared with SHR-2VGO rats, LFB staining of SHR-2VGO + sp600125 and SHR-2VGO +Acu groups showed significant relaxation of myelin porosity in corpus callosum, striatum, inner capsule, anterior commissure and hippocampal fimbria, and electron microscopy showed improved axonal myelin integrity and thickness in corpus callosum region. Also, the number of blue patchy Nissl bodies increased, and the number and complexity of dendritic spines increased significantly in Golgi staining. Immunohistochemical detection showed that JNK levels in DG and CA3 region were increased and NMDAR1 and NMDAR2B levels were decreased in SHR-2VGO+Acu and SHR-2VGO+ sp600125 groups. Meanwhile, protein expressions of GSK3ß, NMDAR1/p-NMDAR1 and NMDAR2B in fimbria of hippocampus were increased, and JNK/P-JNK protein expression decreased. Acupuncture can increase the density and thickness of myelin sheath in white matter areas of corpus callosum, anterior commissure and hippocampal fimbria, increase the number and length of hippocampal neuronal dendrites, and improve hypertensive white matter injury and cognitive decline through JNK-NMDAR pathway.

7.
Gynecol Endocrinol ; 39(1): 2269248, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37846544

RESUMEN

OBJECTIVE: Estrogen (E2) is the main contributor to the progression of endometrial cancer (EC). The long noncoding RNA HOX antisense intergenic RNA (HOTAIR) is emerging as a new regulator in several cancer types. This study aimed to investigate the role of HOTAIR in EC development and identify the underlying molecular mechanisms. METHODS: HOTAIR expression levels in human EC tissues and the corresponding adjacent tissues and human EC Ishikawa cells were determined by quantitative PCR. Ishikawa cells were treated with E2 or estrogen receptor (ER) inhibitor ICI182780, transfected with siHOTAIR oligo, or infected with lentivirus expressing shHOTAIR/shNC, alone or in combinations. The protein expression of polycomb repressive complex 2 (PRC2) was evaluated by western blotting, and cell migration was measured by transwell assays. A xenograft tumorigenic model was established by inoculating control or stable shHOTAIR-infected Ishikawa cells into nude mice and implanting 17ß-estradiol release pellets. RESULTS: HOTAIR expression was significantly elevated in human EC tissues. E2 exposure markedly increased HOTAIR levels in Ishikawa cells. Notably, E2 increased the protein expression of PRC2 and promoted EC cell migration, which were dependent on HOTAIR expression, as HOTAIR knockdown abolished these effects of E2. Similarly, E2 promoted the in vivo proliferation of grafted Ishikawa cells via upregulated HOTAIR expression in nude mice. CONCLUSIONS: Human EC tissues highly express HOTAIR, and E2-induced EC progression depends on HOTAIR expression. This work suggests that the E2-HOTAIR axis is a potential therapeutic target in EC therapy.


Asunto(s)
Neoplasias Endometriales , ARN Largo no Codificante , Animales , Femenino , Humanos , Ratones , Apoptosis , Línea Celular Tumoral , Proliferación Celular/genética , Neoplasias Endometriales/genética , Neoplasias Endometriales/metabolismo , Estrógenos/farmacología , Regulación Neoplásica de la Expresión Génica , Ratones Desnudos , ARN Largo no Codificante/genética
8.
Zhen Ci Yan Jiu ; 48(10): 1033-1040, 2023 Oct 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-37879954

RESUMEN

OBJECTIVES: To investigate the effect of electroacupuncture(EA) at "Changbing Decoction" on alleviating ulcerative colitis (UC) and regulating the polarization of colonic macrophages in rats, so as to explore its mechanisms underlying improvement of UC. METHODS: Twenty-six male SD rats were randomly divided into 4 groups:normal group(6 rats), model group(8 rats), EA group(6 rats), and western medication group(6 rats). The rat model of UC was established by using 5% dextran sulfate sodium (DSS) solution drinking water for 7 days, followed by drinking 1% DSS solution during treatment period. After 7-day model establishment, EA treatment(10 Hz/50 Hz, 20 min) was applied to "Zhongwan"(CV12), bilateral "Tianshu"(ST25) and "Shangjuxu"(ST37) for 3 d, and rats in the western medication group were given mesalazine suspension(200 mg/kg) by gavage for 3 d. The body weight, spleen weight and colon length of rats were measured. The disease activity index (DAI) score was evaluated. The morphological changes and inflammatory cell infiltration of colon were detected after HE staining and pathological scores were eva-luated. The contents of tumor necrosis factor α(TNF-α), interleukin(IL)-1ß, IL-2 and IL-10 in serum were detected by ELISA. The protein expressions of M1 and M2 macrophage markers nitric oxide synthase (iNOS) and arginase 1(Arg1) were detected by fluorescence double staining and Western blot, respectively. Quantitative real-time PCR was used to detect iNOS and Arg1 mRNA expressions. RESULTS: Compared with the normal group, rats in the model group had increased pathological damage degree and inflammatory cell infiltration in the colon tissue, slowed-down body weight gain, decreased colon length, spleen weight, serum anti-inflammatory factors IL-2 and IL-10 contents, colonic Arg1/CD68 fluorescence positive expression, and Arg1 protein and mRNA expressions(P<0.01, P<0.05), as well as increased DAI scores, colon histopathological scores, contents of serum pro-inflammatory factors TNF-α and IL-1ß, colonic iNOS/CD68 fluorescence positive expression, iNOS protein and mRNA expressions(P<0.01). Compared with the model group, the above indicators were significantly improved in rats of the EA group and the western medication group(P<0.01, P<0.05). CONCLUSIONS: EA of "Changbing Decoction" can improve UC of rats by regulating the polarization of colonic macrophages, inhibiting the generation of M1 macrophages and promoting the generation of M2 macrophages.


Asunto(s)
Colitis Ulcerosa , Electroacupuntura , Ratas , Masculino , Animales , Colitis Ulcerosa/genética , Colitis Ulcerosa/terapia , Interleucina-10/genética , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/genética , Interleucina-2 , Macrófagos , ARN Mensajero , Peso Corporal
9.
J Am Chem Soc ; 145(44): 23939-23947, 2023 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-37748140

RESUMEN

Autophagy is responsible for the degradation of large intracellular contents, such as unwanted protein aggregates and organelles. Impaired autophagy can therefore lead to the accumulation of pathological aggregates, correlating with aging and neurodegenerative diseases. However, a broadly applicable methodology is not available for the targeted degradation of protein aggregates or organelles in mammalian cells. Herein, we developed a series of autophagy receptor-inspired targeting chimeras (AceTACs) that can induce the targeted degradation of aggregation-prone proteins and protein aggregates (e.g., huntingtin, TDP-43, and FUS mutants), as well as organelles (e.g., mitochondria, peroxisomes, and endoplasmic reticulum). These antibody-fusion-based AceTAC degraders were designed to mimic the function of autophagy receptors, simultaneously binding with the cellular targets and the LC3 proteins on the autophagosomal membrane, eventually transporting the target to the autophagy-lysosomal process for degradation. The AceTAC degradation system provides design principles for antibody-based degradation through autophagy, largely expanding the scope of intracellular targeted degradation technologies.


Asunto(s)
Autofagia , Agregado de Proteínas , Animales , Retículo Endoplásmico/metabolismo , Lisosomas , Peroxisomas/metabolismo , Mamíferos
10.
Zhen Ci Yan Jiu ; 48(8): 818-24, 2023 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-37614141

RESUMEN

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Zhongwan" (CV12), "Tianshu" (ST25) and "Shangjuxu" (ST37) (an acupoint prescription "Changbingfang" for treatment of intestinal disorders) on autophagy and expression of AMPK/mTOR signaling pathway in rats with ulcerative colitis (UC), so as to explore its mechanism underlying improvement of UC. METHODS: Thirty-two male SD rats were randomly divided into control, model, medication and EA groups, with 8 rats in each group. The UC model was established by free drinking of 5% dextran sulfate sodium salt solution for 7 days. EA stimulation (10 Hz/50 Hz) was delivered to CV12, ST25 and ST37 for 20 min, once a day for 3 consecutive days. Rats of the medication group received gavage of mesalazine suspension (200 mg/kg) once a day, 3 times in total. The rats' general conditions were recorded for calculating the disease activity index (DAI) score (0-4 points). Histomorphological changes of colon were observed via HE staining. The levels of serum interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α) and IL-10 were measured by ELISA. The mRNA expressions of LC3B and p62 were tested by fluorescence quantitative PCR. Western blot was used to detect the expression levels of LC3B, p62 and AMPK/mTOR pathway related proteins in colon tissues. RESULTS: Compared with the control group, the DAI score, contents of serum IL-6 and TNF-α, the expression levels of p62 protein and mRNA, ratio of p-mTOR/mTOR were significantly increased (P<0.01); while the content of serum IL-10, the expression levels of LC3B mRNA, ratio of LC3BⅡ/LC3BⅠ and p-AMPK/AMPK were decreased (P<0.01, P<0.05) in the model group. Relevant to the model group, modeling-induced increases of DAI score, serum IL-6, TNF-α and IL-10 contents, expressions of p62 protein and mRNA, LC3B mRNA, ratio of p-mTOR/mTOR, LC3BⅡ/LC3BⅠ and p-AMPK/AMPK were reversed in both medication and EA groups (P<0.01, P<0.05). The effect of EA was apparently superior to that of mesalazine in up-regulating ratio of LC3BⅡ/LC3BⅠ and p-AMPK/AMPK, p62 mRNA expression (P<0.01, P<0.05), and in down-regulating ratio of p-mTOR/mTOR (P<0.05). H.E. staining showed severe damage of the colonic mucosal barrier with infiltration of a large number of inflammatory cells in the model group, which was milder in medication and EA groups. CONCLUSION: EA of acupoint recipe "Changbingfang" can improve the symptoms in UC rats, which may be related to its functions in promoting colonic autophagy, increasing AMPK phosphorylation level, and decreasing mTOR phosphorylation level.


Asunto(s)
Colitis Ulcerosa , Electroacupuntura , Masculino , Animales , Ratas , Ratas Sprague-Dawley , Colitis Ulcerosa/genética , Colitis Ulcerosa/terapia , Proteínas Quinasas Activadas por AMP/genética , Interleucina-10 , Mesalamina , Interleucina-6 , Factor de Necrosis Tumoral alfa/genética , Transducción de Señal , Serina-Treonina Quinasas TOR/genética , ARN Mensajero , Autofagia
11.
Brain Behav ; 13(7): e3078, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37269140

RESUMEN

BACKGROUND: Previous studies have suggested that ambient temperature is associated with the morbidity and mortality of stroke although results among these investigations remained unclear. Therefore, the purpose of present meta-analysis was to summarize the evidence of the relationship between ambient temperature and stroke morbidity and mortality. METHODS: A systematic search of the PubMed, Embase, and Web of Science databases was from inception to April 13, 2022. The pooled estimates for heat ambient temperature and cold ambient temperature, which were defined as comparison between extreme hot or cold conditions and the reference or threshold temperature, were calculated utilizing a random-effects model. A total of 20 studies were included in the meta-analysis. RESULTS: The pooled estimated show that the heat ambient temperature was significant associated with 10% (relative risk [RR], 1.10; 95% confidence interval [95%CI]: 1.02-1.18) and 9% (RR, 1.09; 95%CI: 1.02-1.17) increase in the risk of stroke morbidity and mortality, respectively. In addition, the pooled estimated show that the cold ambient temperature was significant associated with 33% (RR, 1.33; 95%CI: 1.17-1.51) and 18% (RR, 1.18; 95%CI: 1.06-1.31) increase in the risk of stroke morbidity and mortality, respectively. CONCLUSION: Integrated epidemiological evidence supports the hypothesis that both heat and cold ambient temperature have positive association with the risk of stroke morbidity and mortality. Targeted measures should be promoted in public health to reduce this risk.


Asunto(s)
Frío , Accidente Cerebrovascular , Humanos , Temperatura , Calor , Accidente Cerebrovascular/epidemiología , Morbilidad
12.
Clin Lab ; 69(3)2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36912293

RESUMEN

BACKGROUND: The object of the study was to explore the risk factors for endometrial polyps (EP) by analyzing the clinical characteristics and laboratory findings. METHODS: From January 2019 to June 2020, clinical data from 183 patients treated with gynecological hysteroscopic surgery were collected. Among them were 118 EP cases which were included into the study group. They were divided into four groups by age: Group 1: < 30 years old (9, 7.6%), Group 2: ≥ 30 < 40 years old (62, 52.5%), Group 3: ≥ 40 < 50 years of age (39, 33.1%), Group 4: ≥ 50 years of age (8, 6.8%). The remaining 65 patients with uterine adhesion were used as controls. RESULTS: Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), hemoglobin (HGB), and uterine volume between the two groups were statistically significant. TC, LDL-C, and uterine volume were identified as independent risk factors for EP, with TC being the most significant. In patients < 40 years of age, HGB, LDL-C, and uterine volume were significantly different, with LDL-C and uterine volume acting as independent risk factors and uterine volume being more significant. There were differences in the overall distribution of blood flow signal ratio in the EP age groups. Menarche occurred significantly earlier in Groups 1, 2, and 3 than in groups 4. Uterine volume was significantly smaller in Group 1 than Group 3. LDL-C and uterine volume had better prediction values for EP. When the uterine volume was 61.65 cm3, the sensitivity was 58.6%, and the specificity was 93.5%. CONCLUSIONS: In clinical practice, attention should be paid to the cholesterol metabolism in EP patients.


Asunto(s)
Pólipos , Enfermedades Uterinas , Femenino , Humanos , Adulto , LDL-Colesterol , Metabolismo de los Lípidos , Enfermedades Uterinas/cirugía , Pólipos/cirugía , Factores de Riesgo , HDL-Colesterol
13.
Biochemistry ; 61(21): 2295-2302, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36264309

RESUMEN

Autophagy is a catabolic cellular process in which unwanted proteins and organelles are degraded by lysosomes. It is characterized by the formation of the double-membrane autophagosome decorated with LC3B, a protein that mediates autophagosomal fusion with lysosomes. The cysteine protease ATG4b acts at two stages in the life cycle of LC3B. We set out to characterize the protein-protein interaction between LC3B and ATG4b. Through biochemical and biophysical studies, we show that the ubiquitin-like core of LC3B (residues 1-115; "LC3B-115"), which lacks the C-terminal cleavage site (between residue 120 and 121), binds to full-length ATG4b with a surprisingly tight dissociation constant (KD) in the low nanomolar range; 10-30-fold tighter than that of the substrate pro-LC3B (residues 1-125) or the product LC3B-I (residues 1-120). Consequently, LC3B-115 is a potent inhibitor of the ATG4b-mediated cleavage of pro-LC3B (IC50 = 15 nM). Binding of the LC3B-115 has no effect on the conformation of the active site of ATG4b, as judged by the turnover of a peptide substrate ("substrate-33"), derived from LC3B-I residues 116-120. Conversely, truncations of ATG4b show that binding and proteolysis of LC3B critically depend on the C-terminal tail of ATG4b, whereas proteolysis of the peptide substrate-33 does not require the C-terminal tail of ATG4b. These results support a bipartite model for LC3B-ATG4b binding in which the core of LC3B binds to ATG4b and the C-terminal tail of pro-LC3B organizes the ATG4b active site; additionally, the C-terminal tail of ATG4b contributes at least 1000-fold higher binding affinity to the LC3B-ATG4b interaction and likely wraps around the LC3B-ubiquitin core. PPIs are often described as containing an energetic "hot spot" for binding; in the case of LC3B-ATG4b, however, the substrate-enzyme complex contains multiple, energetically relevant domains that differentially affect binding affinity and catalytic efficiency.


Asunto(s)
Cisteína Endopeptidasas , Péptido Hidrolasas , Proteínas Relacionadas con la Autofagia , Cisteína Endopeptidasas/metabolismo , Autofagia , Familia de las Proteínas 8 Relacionadas con la Autofagia , Péptidos/farmacología , Proteínas Asociadas a Microtúbulos/metabolismo
14.
Phys Rev E ; 106(2-2): 025317, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36109997

RESUMEN

The numerical solution of coupled nonlinear Klein-Gordon equations on unbounded domains is considered by applying the artificial boundary method. Based on the unified approach to overcome the coupled nonlinearity, local artificial boundary conditions are designed on the introduced artificial boundaries. The original problem is reduced to an initial boundary value problem on a bounded domain, which can be efficiently solved by the finite difference method. Some numerical examples are provided to verify the accuracy and effectiveness of the proposed method.

15.
J Am Chem Soc ; 144(29): 13218-13225, 2022 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-35819848

RESUMEN

Protein-protein interactions (PPIs) form complex networks to drive cellular signaling and cellular functions. Precise modulation of a target PPI helps explain the role of the PPI in cellular events and possesses therapeutic potential. For example, valosin-containing protein (VCP/p97) is a hub protein that interacts with more than 30 adaptor proteins involved in various cellular functions. However, the role of each p97 PPI during the relevant cellular event is underexplored. The development of small-molecule PPI modulators remains challenging due to a lack of grooves and pockets in the relatively large PPI interface and the fact that a common binding groove in p97 binds to multiple adaptors. Here, we report an antibody fragment-based modulator for the PPI between p97 and its adaptor protein NSFL1C (p47). We engineered these antibody modulators by phage display against the p97-interacting domain of p47 and minimizing binding to other p97 adaptors. The selected antibody fragment modulators specifically disrupt the intracellular p97/p47 interaction. The potential of this antibody platform to develop PPI inhibitors in therapeutic applications was demonstrated through the inhibition of Golgi reassembly, which requires the p97/p47 interaction. This study presents a unique approach to modulate specific intracellular PPIs using engineered antibody fragments, demonstrating a method to dissect the function of a PPI within a convoluted PPI network.


Asunto(s)
Adenosina Trifosfatasas , Proteínas de Ciclo Celular , Proteínas Adaptadoras Transductoras de Señales/química , Adenosina Trifosfatasas/metabolismo , Proteínas de Ciclo Celular/química , Fragmentos de Inmunoglobulinas , Unión Proteica , Proteína que Contiene Valosina/metabolismo
16.
Colloids Surf B Biointerfaces ; 216: 112553, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35598508

RESUMEN

Due to the adverse effects of free drugs on the fetus, placental-mediated pregnancy complications still lack effective pharmacotherapy. This study aims to construct a non-spherical drug delivery system based on folate-conjugated pullulan acetate (FPA) for placental targeting and translocation. By adjusting the initial solvent system, FPA nanoparticles with different morphologies were prepared using dialysis method without a surfactant. Cytotoxicity and lactate dehydrogenase release assays indicated the good biocompatibility of FPA nanoparticles in BeWo b30 cells. Cellular uptake and in vitro placental barrier transportation studies showed that FPA nanoparticles entered the cells and transported across the cell monolayer, benefiting from the active target effect mediated by the folate receptor. Moreover, non-spherical FPA nanoparticles showed nuclear translocation due to their shape effect. These findings provide a novel aspect in placental-mediated pregnancy treatment and applications in the obstetrics field of drug use during pregnancy.


Asunto(s)
Ácido Fólico , Nanopartículas , Acetatos , Línea Celular Tumoral , Femenino , Glucanos , Humanos , Placenta , Embarazo
17.
Nanoscale ; 14(6): 2411-2418, 2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-35089292

RESUMEN

Control over supramolecular recognition between proteins and nanoparticles (NPs) is of fundamental importance in therapeutic applications and sensor development. Most NP-protein binding approaches use 'tags' such as biotin or His-tags to provide high affinity; protein surface recognition provides a versatile alternative strategy. Generating high affinity NP-protein interactions is challenging however, due to dielectric screening at physiological ionic strengths. We report here the co-engineering of nanoparticles and protein to provide high affinity binding. In this strategy, 'supercharged' proteins provide enhanced interfacial electrostatic interactions with complementarily charged nanoparticles, generating high affinity complexes. Significantly, the co-engineered protein-nanoparticle assemblies feature high binding affinity even at physiologically relevant ionic strength conditions. Computational studies identify both hydrophobic and electrostatic interactions as drivers for these high affinity NP-protein complexes.


Asunto(s)
Nanopartículas , Interacciones Hidrofóbicas e Hidrofílicas , Unión Proteica , Proteínas , Electricidad Estática
18.
Acta Biochim Biophys Sin (Shanghai) ; 52(12): 1337-1347, 2020 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-33313721

RESUMEN

Homeobox transcript antisense RNA (HOTAIR) is a long non-coding RNA associated with a number of fibrosis-related diseases. The aim of this study was to investigate the specific role of HOTAIR in the development of endometrial fibrosis and to identify the molecular mechanisms underlying this process. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine the expression levels of HOTAIR in samples of intrauterine adhesion (IUA) tissue and in endometrial stromal cells (ESCs) that had been treated with transforming growth factor beta 1 (TGF-ß1). Additionally, we transfected ESCs with either overexpression plasmid (pcDNA-HOTAIR) or silencing construct (si-HOTAIR) and then treated these cells with TGF-ß1. We then performed RT-qPCR and western blot analysis, along with cell proliferation and apoptosis assays, to investigate the effects of HOTAIR on the transdifferentiation of ESCs into myofibroblasts. The results showed that the expression levels of HOTAIR were significantly elevated in IUA tissue and in ESCs that had been treated with TGF-ß1. The overexpression of HOTAIR had a pro-fibrotic effect on ESCs, while the silencing of HOTAIR exerted an anti-fibrotic effect. Most importantly, the protein expression levels of p-Smad2 and p-Smad3 were significantly upregulated in TGF-ß1-treated ESCs transfected with pcDNA-HOTAIR and were downregulated after transfection with si-HOTAIR constructs. These data indicate that HOTAIR promotes endometrial fibrosis by activating the TGF-ß1/Smad signaling pathway, suggesting that the inhibition of HOTAIR may represent a promising therapeutic option for suppressing endometrial fibrosis.


Asunto(s)
Fibrosis/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Enfermedades Uterinas/genética , Actinas/metabolismo , Adulto , Apoptosis/genética , Proliferación Celular/genética , Transdiferenciación Celular/genética , Colágeno Tipo I/metabolismo , Cadena alfa 1 del Colágeno Tipo I , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Cultivo Primario de Células , Transducción de Señal/genética , Proteína Smad2/genética , Proteína smad3/genética , Células del Estroma/metabolismo , Adherencias Tisulares/genética , Adherencias Tisulares/metabolismo , Factor de Crecimiento Transformador beta1/fisiología , Regulación hacia Arriba , Enfermedades Uterinas/patología
19.
Curr Protoc Chem Biol ; 12(4): e85, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33207082

RESUMEN

Reversible addition-fragmentation chain-transfer (RAFT) polymerization is a commonly used polymerization methodology to generate synthetic polymers. The products of RAFT polymerization, i.e., RAFT polymers, have been widely employed in several biologically relevant areas, including drug delivery, biomedical imaging, and tissue engineering. In this article, we summarize a synthetic methodology to display an azide group at the chain end of a RAFT polymer, thus presenting a reactive site on the polymer terminus. This platform enables a click reaction between azide-terminated polymers and alkyne-containing molecules, providing a broadly applicable scaffold for chemical and bioconjugation reactions on RAFT polymers. We also highlight applications of these azide-terminated RAFT polymers in fluorophore labeling and for promoting organelle targeting capability. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Synthesis of the azide derivatives of chain transfer agent and radical initiator Basic Protocol 2: Installation of an azide group on the α-end of RAFT polymers Alternate Protocol: Installation of an azide group on the ω-end of RAFT polymers Basic Protocol 3: Click reaction between azide-terminated RAFT polymers and alkyne derivatives.


Asunto(s)
Azidas/química , Diagnóstico por Imagen , Sistemas de Liberación de Medicamentos , Polímeros/química , Ingeniería de Tejidos , Azidas/síntesis química , Química Clic , Polimerizacion , Polímeros/síntesis química
20.
Bioconjug Chem ; 31(5): 1344-1353, 2020 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-32208679

RESUMEN

Mitochondria are therapeutic targets in many diseases including cancer, metabolic disorders, and neurodegenerative diseases. Therefore, strategies to deliver therapeutics of interest to mitochondria are important for therapeutic development. As delocalized lipophilic cations (DLCs) preferentially accumulate in mitochondria, DLC-conjugation has been utilized to facilitate therapeutic delivery systems with mitochondrial targeting capability. Here we report that upon DLC-conjugation, anionic polymers exhibit significantly improved mitochondrial targeting when compared to cationic polymers and charge-neutral polymers. Considering that the cell membrane generally bears a net negative charge, the observed phenomenon is unexpected. Notably, the DLC-conjugated anionic polymers circumvent endosomal entrapment. The rapid mitochondrial accumulation of DLC-conjugated anionic polymers is likely a membrane-potential-driven process, along with the involvement of the mitochondrial pyruvate carrier. Moreover, the structural variations on the side chain of DLC-conjugated anionic polymers do not compromise the overall mitochondrial targeting capability, widely extending the applicability of anionic macromolecules in therapeutic delivery systems.


Asunto(s)
Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Interacciones Hidrofóbicas e Hidrofílicas , Mitocondrias/metabolismo , Polímeros/química , Polímeros/metabolismo , Células HeLa , Humanos , Cinética , Potencial de la Membrana Mitocondrial
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