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1.
Molecules ; 29(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38474531

RESUMO

A enantioselective tandem transformation, concerning asymmetric allylic decarboxylative addition and cyclization of N-nosylimines with vinylethylene carbonates (VECs), in the presence of [Rh(C2H4)2Cl]2, chiral sulfoxide-N-olefin tridentate ligand has been developed. The reaction of VECs with various substituted N-nosylimines proceeded smoothly under mild conditions, providing highly functionalized oxazolidine frameworks in good to high yields with good to excellent enantioselectivity.

2.
Angew Chem Int Ed Engl ; 63(28): e202404329, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38683742

RESUMO

A hitherto unknown class of C4-symmetric Caryl-Cß (C3, C8, C13, C18) axially chiral porphyrins has been synthesized and the application of their iridium (Ir) complexes in catalytic asymmetric C(sp3)-H functionalization is documented. Cyclotetramerization of enantioenriched axially chiral 2-hydroxymethyl-3-naphthyl pyrroles under mild acidic conditions affords, after oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), the C4-symmetric α,α,α,α-atropenantiomer as an only isolable diastereomer. Both regioisomeric Ir(Por*)(CO)(Cl) complexes catalyze the carbene C-H insertion reaction affording the same enantiomer, albeit with slight difference in enantioselectivity. With the optimum Ir-complex 3 e, the 2-substituted arylacetic acid derivatives were generated from diazo compounds and cyclohexadiene in excellent yields and enantioselectivities.

3.
Cell Mol Neurobiol ; 43(7): 3251-3263, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37382853

RESUMO

The abnormal initiation of autophagy flux in neurons after ischemic stroke caused dysfunction of autophagy-lysosome, which not only led to autophagy flux blockage, but also resulted in autophagic death of neurons. However, the pathological mechanism of neuronal autophagy-lysosome dysfunction did not form a unified viewpoint until now. In this review, taking the autophagy lysosomal dysfunction of neurons as a starting point, we summarized the molecular mechanisms that led to neuronal autophagy lysosomal dysfunction after ischemic stroke, which would provide theoretical basis for the clinical treatment of ischemic stroke.


Assuntos
Autofagia , AVC Isquêmico , Lisossomos , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , AVC Isquêmico/terapia , Humanos , Animais , Neurônios/metabolismo , Neurônios/patologia , Lisossomos/patologia , Reperfusão , Proteínas do Tecido Nervoso/metabolismo
4.
Molecules ; 27(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36296572

RESUMO

The utilization of 6,6-dimethyl-3-((trimethylsilyl)oxy)cyclohex-2-en-1-one made from an unsymmetrical 4,4-dimethylcyclohexane-1,3-dione in iridium-catalyzed allylic enolization involving keto-enol isomerization is accomplished under mild conditions. The chemoselectivity, regioselectivity, and enantioselectivity are facilitated by the quaternary carbon and adjusting the reaction conditions. This method provides the substituted 2-(but-3-en-2-yl)-3-hydroxy-6,6-dimethylcyclohex-2-en-1-ones in good to high yields with high level of chemo-, regio-, and enantioselectivities. The chiral carbon-fluorine bond formation is induced by an adjacent chiral carbon center of the allylated 3-hydroxy-6,6-dimethylcyclohex-2-en-1-one, as well.


Assuntos
Flúor , Irídio , Irídio/química , Estereoisomerismo , Catálise , Isomerismo , Carbono
5.
Phys Rev Lett ; 127(11): 116801, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34558927

RESUMO

Systems with non-Hermitian skin effects are very sensitive to the imposed boundary conditions and lattice size, and thus an important question is whether non-Hermitian skin effects can survive when deviating from the open boundary condition. To unveil the origin of boundary sensitivity, we present exact solutions for one-dimensional non-Hermitian models with generalized boundary conditions and study rigorously the interplay effect of lattice size and boundary terms. Besides the open boundary condition, we identify the existence of non-Hermitian skin effect when one of the boundary hopping terms vanishes. Apart from this critical line on the boundary parameter space, we find that the skin effect is fragile under any tiny boundary perturbation in the thermodynamic limit, although it can survive in a finite size system. Moreover, we demonstrate that the non-Hermitian Su-Schreieffer-Heeger model exhibits a new phase diagram in the boundary critical line, which is different from either open or periodical boundary case.

6.
Pflugers Arch ; 472(1): 117-133, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31875236

RESUMO

Complexin I (CPLX1), a presynaptic small molecule protein, forms SNARE complex in the central nervous system involved in the anchoring, pre-excitation, and fusion of axonal end vesicles. Abnormal expression of CPLX1 occurs in several neurodegenerative and psychiatric disorders that exhibit disrupted neurobehaviors. CPLX1 gene knockout induces severe ataxia and social behavioral deficits in mice, which has been poorly demonstrated. Here, to address the limitations of single-species models and to provide translational insights relevant to human diseases, we used CPLX1 knockout rats to further explore the function of the CPLX1 gene. The CRISPR/Cas9 gene editing system was adopted to generate CPLX1 knockout rats (CPLX1-/-). Then, we characterized the survival rate and behavioral phenotype of CPLX1-/- rats using behavioral analysis. To further explain this phenomenon, we performed blood glucose testing, Nissl staining, hematoxylin-eosin staining, and Golgi staining. We found that CPLX1-/- rats showed profound ataxia, dystonia, movement and exploratory deficits, and increased anxiety and sensory deficits but had normal cognitive function. Nevertheless, CPLX1-/- rats could swim without training. The abnormal histomorphology of the stomach and intestine were related to decreased weight and early death in these rats. Decreased dendritic branching was also found in spinal motor neurons in CPLX1-/- rats. In conclusion, CPLX1 gene knockout induced the abnormal histomorphology of the stomach and intestine and decreased dendritic branching in spinal motor neurons, causing different phenotypes between CPLX1-/- rats and mice, even though both of these phenotypes showed profound ataxia. These findings provide a new perspective for understanding the role of CPLX1.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Ataxia/genética , Distonia/genética , Deleção de Genes , Longevidade/genética , Proteínas do Tecido Nervoso/metabolismo , Fenótipo , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Ataxia/patologia , Dendritos/patologia , Distonia/patologia , Comportamento Exploratório , Intestinos/patologia , Neurônios Motores/patologia , Movimento , Proteínas do Tecido Nervoso/genética , Ratos , Ratos Sprague-Dawley , Estômago/patologia
7.
Biochem Biophys Res Commun ; 489(2): 149-154, 2017 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-28546004

RESUMO

Gene arrangements in the mitochondrial genomes (mitogenomes) of insects are conserved across the major lineages, but can be rearranged within derived groups and may provide valuable phylogenetic characters. In this study, we sequenced the entire mitogenome of Parasa consocia, a moth of the family Limacodidae (Lepidoptera: Zygaenoidea). Compared with other lepidopterans and ancestral insects, the P. consocia mitogenome features a transfer RNA gene arrangement novel among lepidopterans between the ND3 and ND5 genes: RANSEF (the underline signifies an inverted gene), which differs from the ARNSEF arrangement of ancestral insects. This rearrangement can be explained by the tandem duplication-random loss model. We inferred a phylogenetic hypothesis for the lepidopteran superfamily based on mitochondrial amino-acid sequences using the Bayesian-inference and maximum-likelihood methods. Our results showed that P. consocia belongs to the Zygaenoidea superfamily and supported the following phylogenetic relationship: Yponomeutoidea + (Tortricoidea + Zygaenoidea + (Papilionoidea + (Pyraloidea + (Noctuoidea + (Geometroidea + Bombycoidea)))))). Comparative analyses indicated that mitogenomes are a useful phylogenetic tool at the subfamily level within the order Lepidoptera. Our findings also suggest that mitogenomes are likely to represent a valuable tool for systematics in other groups of lepidopterans.


Assuntos
Ordem dos Genes/genética , Genoma Mitocondrial/genética , RNA de Transferência/genética , Animais , Mariposas , Filogenia
8.
J Biol Chem ; 290(2): 972-86, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25371208

RESUMO

The genes responsible for silk biosynthesis are switched on and off at particular times in the silk glands of Bombyx mori. This switch appears to be under the control of endogenous and exogenous hormones. However, the molecular mechanisms by which silk protein synthesis is regulated by the juvenile hormone (JH) are largely unknown. Here, we report a basic helix-loop-helix transcription factor, Bmdimm, its silk gland-specific expression, and its direct involvement in the regulation of fibroin H-chain (fib-H) by binding to an E-box (CAAATG) element of the fib-H gene promoter. Far-Western blots, enzyme-linked immunosorbent assays, and co-immunoprecipitation assays revealed that Bmdimm protein interacted with another basic helix-loop-helix transcription factor, Bmsage. Immunostaining revealed that Bmdimm and Bmsage proteins are co-localized in nuclei. Bmdimm expression was induced in larval silk glands in vivo, in silk glands cultured in vitro, and in B. mori cell lines after treatment with a JH analog. The JH effect on Bmdimm was mediated by the JH-Met-Kr-h1 signaling pathway, and Bmdimm expression did not respond to JH by RNA interference with double-stranded BmKr-h1 RNA. These data suggest that the JH regulatory pathway, the transcription factor Bmdimm, and the targeted fib-H gene contribute to the synthesis of fibroin H-chain protein in B. mori.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fibroínas/genética , Proteínas de Insetos/genética , Hormônios Juvenis/genética , Seda/biossíntese , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Bombyx/genética , Fibroínas/metabolismo , Proteínas de Insetos/biossíntese , Hormônios Juvenis/metabolismo , Larva , Regiões Promotoras Genéticas/genética , Sericinas/biossíntese , Sericinas/genética
9.
Org Biomol Chem ; 14(30): 7183-6, 2016 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-27383920

RESUMO

Enantioselective introduction of the functionalized monofluorinated methylenes into the allylic fragment under Ir catalysis has been realized, which gave the fluorinated branched allyl products in good to high yields with excellent regio- and enantioselectivities.

10.
Org Biomol Chem ; 13(37): 9551-8, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26288320

RESUMO

New chiral S,N- and S,P-ligands starting from tert-butanesulfinamide were synthesized in four steps, applying Pd-catalyzed asymmetric allylic substitutions of dimethyl 2-fluoromalonate. The induced effect of the Pd/S,N-ligand catalyst on the enantioselectivity depends on the steric demand of the substituent at the o-position of the pyridine ring. This method produced monofluorinated allylation products in up to high yield with high enantioselectivity.


Assuntos
Compostos Alílicos/química , Halogenação , Malonatos/química , Malonatos/síntese química , Paládio/química , Compostos de Sulfônio/química , Catálise , Técnicas de Química Sintética , Ligantes , Estereoisomerismo
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(8): 825-9, 2015 Aug.
Artigo em Zh | MEDLINE | ID: mdl-26287347

RESUMO

OBJECTIVE: To measure the expression of lymphocyte function-associated antigen-3 (CD58) in childhood B-lineage acute lymphoblastic leukemia (B-ALL) and to explore the feasibility of CD58 as an indicator for minimal residual disease (MRD) detection in childhood B-ALL. METHODS: Eighty-seven children diagnosed with B-ALL between January 2014 and September 2014 were enrolled, and 20 hospitalized children who had no tumor or blood disease and had normal bone marrow cell morphology served as the control group. The expression features of CD58 in bone marrow samples from the two groups (at diagnosis, on day 15 of induction chemotherapy) were analyzed by four-color flow cytometry (FCM). Quantitative real-time polymerase chain reaction (qRT-PCR) and FCM were used to detect MRD in B-ALL patients on day 33 of induction chemotherapy. RESULTS: The mean fluorescence intensity of CD58 expression in the 87 B-ALL cases (91±33) was significantly higher than that in the 20 controls (14±6) (P<0.01); CD58 was over-expressed in 44 of the B-ALL cases. In the B-ALL children, the expression of CD58 on day 15 of induction chemotherapy (105±22) was not significantly different from that at diagnosis (107±26) (P>0.05). In the 44 B-ALL patients with CD58 over-expression, FCM showed 9 MRD(+) cases and 35 MRD(-) cases, while qRT-PCR showed 11 MRD(+) cases and 33 MRD(-) cases; 42 cases (95%) showed consistent results of the two tests, so there was no significant difference between the two methods in detecting MRD (P>0.05). CONCLUSIONS: CD58 is over-expressed and stable in children with B-ALL, and it can be considered as an indicator for MRD detection in childhood B-ALL.


Assuntos
Antígenos CD58/análise , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Adolescente , Linhagem da Célula , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Humanos , Quimioterapia de Indução , Lactente , Masculino , Neoplasia Residual/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico
12.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(3): 258-61, 2015 Mar.
Artigo em Zh | MEDLINE | ID: mdl-25815496

RESUMO

OBJECTIVE: To study the expression of Foxp3 and NFAT1 protein in peripheral blood (PB) in children with aplastic anemia (AA) and their roles in the pathogenesis of AA. METHODS: The expression levels of Foxp3 and NFAT1 protein of mononuclear cells in PB were measured by Western blot in 68 children with AA before and after treatment and in 60 normal children (control group). The correlation between Foxp3 and NFAT1 protein expression and the correlation of the Foxp3 and NFAT1 protein expression with blood Hb, WBC and platelet levels were analyzed. RESULTS: The expression levels of Foxp3 and NFAT1 protein in PB in the acute phase in the AA group were significantly lower than in the control group (P<0.05). After treatment (recovery phase) the expression levels of Foxp3 and NFAT1 protein increased obviously compared with those in the acute phase (P<0.05). The Foxp3 protein level was positively correlated with the NFAT1 protein level (r=0.812, P<0.05). Both the Foxp3 and NFAT1 protein levels were positively correlated with blood Hb, WBC and platelet levels in children with AA in the recovery phase (r=0.537, 0.579, 0.655 respectively; P<0.05). CONCLUSIONS: The Foxp3 and NFAT1 protein levels in PB are reduced in children with AA, suggesting that they are involved in the pathogenesis of AA. The measurement of Foxp3 and NFAT1 protein levels may be useful in the severity evaluation of AA.


Assuntos
Anemia Aplástica/sangue , Fatores de Transcrição Forkhead/sangue , Fatores de Transcrição NFATC/sangue , Adolescente , Anemia Aplástica/etiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(1): 26-30, 2015 Jan.
Artigo em Zh | MEDLINE | ID: mdl-25616288

RESUMO

OBJECTIVE: To investigate the association of childhood hemophagocytic syndrome (HPS) with human parvovirus B19 (HPVB19) infection, and to analyze the clinical features of this disease. METHODS: ELISA and quantitative real-time PCR were used to detect HPVB19-IgM, HPVB19-IgG and HPVB19-DNA in 65 children with HPS (HPS group) and 65 healthy children (control group). The HPS group was divided into HPVB19-infected (n=14) and non-infected (n=51) groups according to the detection results of HPVB19-DNA. The clinical data of two groups were compared. RESULTS: The positive rate of HPVB19-IgM in the HPS group (26%, 17/65) was significantly higher than that in the control group (9%, 6/65) (P=0.011), and there was no significant difference in the positive rate of HPVB19-IgG between the HPS (38%, 25/65) and control groups (29%, 19/65) (P=0.266). The infection rate of HPVB19 in the HPS group (22%, 14/65) was significantly higher than that in the control group (3%, 2/65) (P=0.001). Compared with the non-infected group, the HPVB19-infected group had significantly lower platelet count and hemoglobin level on admission, significantly more severe liver function damage, a significantly earlier onset time, and a significantly longer course of disease (P<0.05). CONCLUSIONS: The pathogenesis of HPS may be associated with HPVBl9 infection. HPVBl9-infected children with HPS have more acute onset, more severe clinical manifestations, and a longer disease duration.


Assuntos
Linfo-Histiocitose Hemofagocítica/etiologia , Infecções por Parvoviridae/complicações , Parvovirus B19 Humano , Adolescente , Anticorpos Antivirais/análise , Criança , Pré-Escolar , DNA Viral/análise , Feminino , Humanos , Lactente , Masculino
14.
Chemistry ; 20(24): 7216-21, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24839012

RESUMO

Enantioselective transformation of allyl carbonates into branched allyl carbamates by using amines and recycling CO2 in the presence of an Ir complex and K3PO4 was accomplished. This provided branched allyl carbamates in fair to excellent yields with up to 98:2 regioselectivity and 93 % ee. The role of CO2 in this transformation is discussed as well.

15.
Chemistry ; 20(51): 16873-6, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25367779

RESUMO

An enantioselective allylation reaction of allylic carbonates with sodium sulfite (Na2 SO3 ) catalyzed by Ir complex was accomplished, providing allylic sulfonic acids in good to excellent yields with a high level of enantio- and regioselectivities. (R)-2-Phenyl-2-sulfoacetic acid, a key intermediate for the synthesis of Cefsulodin and Sulbenicillin, was synthesized as well.


Assuntos
Carbonatos/química , Cefsulodina/síntese química , Sulbenicilina/síntese química , Sulfitos/química , Ácidos Sulfônicos/química , Catálise , Cefsulodina/química , Irídio , Estrutura Molecular , Estereoisomerismo , Sulbenicilina/química
16.
Gynecol Endocrinol ; 30(7): 498-501, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24693851

RESUMO

PURPOSE: To compare the clinical result of mini-dose GnRH-a long protocol with short protocol in older patients undergoing IVF. MATERIALS AND METHODS: This was a retrospective study. Four hundred and sixty-one women aged above 35-year-old in first cycle were assigned to two groups: GnRH-a short protocol (n=359); and mini-dose GnRH-a long protocol (n=102). Both groups were divided based on their age, into groups over and under 38 years old. Primary outcome include live birth rate per started cycle. Other clinical outcomes were good-quality embryo rate, clinical pregnancy rate. RESULTS: Patients treated with mini-dose GnRH-a protocol and those treated with short protocol showed similar live birth rate. In the mini-dose long protocol group aged 35-38 years old, patients showed significantly thicker endometrium at the day of hCG administration, higher number of good embryos obtained and higher good-quality embryo rate (56.3% versus 46.5%) compared with short protocol. The implantation rate and clinical pregnancy rate were higher versus short protocol group, but this result was not statistically significant. CONCLUSION(S): Mini-dose GnRH-a long protocol for older women is at least as effective as short protocol, especially in patients aged 35-38 years, with a better good-quality embryo rate and higher number of good embryos obtained, therefore mini-dose GnRH-a long protocol can be considered as an alternative protocol for patients above 35 years age.


Assuntos
Hormônio Liberador de Gonadotropina/agonistas , Infertilidade Feminina/terapia , Folículo Ovariano/fisiologia , Indução da Ovulação/métodos , Pamoato de Triptorrelina/administração & dosagem , Adulto , Fatores Etários , Endométrio/diagnóstico por imagem , Endométrio/fisiologia , Estradiol/sangue , Feminino , Humanos , Recém-Nascido , Infertilidade Feminina/tratamento farmacológico , Nascido Vivo , Hormônio Luteinizante/sangue , Recuperação de Oócitos , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/efeitos dos fármacos , Gravidez , Estudos Retrospectivos , Ultrassonografia
17.
J Assist Reprod Genet ; 31(1): 55-63, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24258349

RESUMO

PURPOSE: Vitrification techniques employ a relatively high concentration of cryoprotectant in vitrification solutions. Exposure of oocytes to high concentrations of cryoprotectant is known to damage the oocytes via both cytotoxic and osmotic effects. Therefore, the key to successful vitrification of oocytes is to strike a balance between the usage of minimal concentration of cryoprotectant without compromising their cryoprotective actions. METHODS: The minimal concentration of ethylene glycol (EG) on mouse oocyte survival and subsequent embryonic development was evaluated following vitrification-warming and parthenogenetic activation. Polyvinylpyrrolidone (PVP) combined with EG on mouse oocyte survival and subsequent embryonic development as well as morphology of the spindle and chromosome alignment were also evaluated. Vitrification system was adapted with JY Straw and the cooling rate was approximately 442-500 °C/min. In contrast, the warming rate was approximately 2,210-2,652 °C/min. RESULTS: Survival rate of oocytes increased significantly when 15 % EG was combined with 2 % PVP in vitrification solution (VS). The effect of combination of EG and PVP was not significant when the concentration of EG was 20 % and higher. Although there were no significant differences in embryonic development, the percentage of abnormal spindle and chromosome alignment was significantly higher in the oocytes without 2 % PVP in VS. CONCLUSIONS: Our data provide a proof of principle for oocyte vitrification that may not require a high concentration of cryoprotectant. There are synergic effects of EG combined with PVP for oocyte vitrification, which may provide important information to the field in developing less cytotoxic VS.


Assuntos
Criopreservação/métodos , Crioprotetores/farmacologia , Desenvolvimento Embrionário/efeitos dos fármacos , Etilenoglicol/farmacologia , Oócitos/efeitos dos fármacos , Povidona/farmacologia , Vitrificação/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Fertilização in vitro , Técnicas de Maturação in Vitro de Oócitos , Camundongos , Oócitos/fisiologia
18.
Insect Sci ; 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214184

RESUMO

The foregut, located at the front of the digestive tract, serves a vital role in insects by storing and grinding food into small particles. The innermost layer of the foregut known as the chitinous intima, comes into direct contact with the food and acts as a protective barrier against abrasive particles. Knickkopf (Knk) is required for chitin organization in the chitinous exoskeleton, tracheae and wings. Despite its significance, little is known about the biological function of Knk in the foregut. In this study, we found that LmKnk was stably expressed in the foregut, and highly expressed before molting in Locusta migratoria. To ascertain the biological function of LmKnk in the foregut, we synthesized specific double-stranded LmKnk (dsLmKnk) and injected it into locusts. Our findings showed a significant decrease in the foregut size, along with reduced food intake and accumulation of residues in the foregut after dsLmKnk injection. Morphological observations revealed that newly formed intima became thinner and lacked chitin lamella. Furthermore, fluorescence immunohistochemistry revealed that LmKnk was located in the apical region of new intima and epithelial cells. Taken together, this study provides insights into the biological function of LmKnk in the foregut, and identifies the potential target gene for exploring biological pest management strategies.

19.
Am J Chin Med ; 52(1): 231-252, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38328828

RESUMO

Berberine has been demonstrated to alleviate cerebral ischemia/reperfusion injury, but its neuroprotective mechanism has yet to be understood. Studies have indicated that ischemic neuronal damage was frequently driven by autophagic/lysosomal dysfunction, which could be restored by boosting transcription factor EB (TFEB) nuclear translocation. Therefore, this study investigated the pharmacological effects of berberine on TFEB-regulated autophagic/lysosomal signaling in neurons after cerebral stroke. A rat model of ischemic stroke and a neuronal ischemia model in HT22 cells were prepared using middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation (OGD), respectively. Berberine was pre-administered at a dose of 100[Formula: see text]mg/kg/d for three days in rats and 90[Formula: see text][Formula: see text]M in HT22 neurons for 12[Formula: see text]h. 24[Formula: see text]h after MCAO and 2[Formula: see text]h after OGD, the penumbral tissues and OGD neurons were obtained to detect nuclear and cytoplasmic TFEB, and the key proteins in the autophagic/lysosomal pathway were examined using western blot and immunofluorescence, respectively. Meanwhile, neuron survival, infarct volume, and neurological deficits were assessed to evaluate the therapeutic efficacy. The results showed that berberine prominently facilitated TFEB nuclear translocation, as indicated by increased nuclear expression in penumbral neurons as well as in OGD HT22 cells. Consequently, both autophagic activity and lysosomal capacity were simultaneously augmented to alleviate the ischemic injury. However, berberine-conferred neuroprotection could be greatly counteracted by lysosomal inhibitor Bafilomycin A1 (Baf-A1). Meanwhile, autophagy inhibitor 3-Methyladenine (3-MA) also slightly neutralized the pharmacological effect of berberine on ameliorating autophagic/lysosomal dysfunction. Our study suggests that berberine-induced neuroprotection against ischemic stroke is elicited by enhancing autophagic flux via facilitation of TFEB nuclear translocation in neurons.


Assuntos
Berberina , Lesões Encefálicas , Isquemia Encefálica , AVC Isquêmico , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Ratos , Animais , Berberina/farmacologia , Berberina/uso terapêutico , Autofagia , Acidente Vascular Cerebral/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Traumatismo por Reperfusão/tratamento farmacológico , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/farmacologia
20.
Cell Signal ; : 111301, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019338

RESUMO

Ischemic stroke is one of the most disabling and fatal diseases around the world. The damaged brain tissues will undergo excessive autophagy, vascular endothelial cells injury, blood-brain barrier (BBB) impairment and neuroinflammation after ischemic stroke. However, there is no unified viewpoint on the underlying mechanism of brain damage. Transforming growth factor-ß1 (TGF-ß1), as a multi-functional cytokine, plays a crucial role in the intricate pathological processes and helps maintain the physiological homeostasis of brain tissues through various signaling pathways after ischemic stroke. In this review, we summarize the protective role of TGF-ß1 in autophagic flux, BBB, vascular remodeling, neuroinflammation and other aspects after ischemic stroke. Based on the review, we believe that TGF-ß1 could serve as a key target for treating ischemic stroke.

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