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1.
J Neurophysiol ; 131(6): 1226-1239, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691531

RESUMO

Mitral/tufted cells (M/TCs) form complex local circuits with interneurons in the olfactory bulb and are powerfully inhibited by these interneurons. The horizontal limb of the diagonal band of Broca (HDB), the only GABAergic/inhibitory source of centrifugal circuit with the olfactory bulb, is known to target olfactory bulb interneurons, and we have shown targeting also to olfactory bulb glutamatergic neurons in vitro. However, the net efficacy of these circuits under different patterns of activation in vivo and the relative balance between the various targeted intact local and centrifugal circuits was the focus of this study. Here channelrhodopsin-2 (ChR2) was expressed in HDB GABAergic neurons to investigate the short-term plasticity of HDB-activated disinhibitory rebound excitation of M/TCs. Optical activation of HDB interneurons increased spontaneous M/TC firing without odor presentation and increased odor-evoked M/TC firing. HDB activation induced disinhibitory rebound excitation (burst or cluster of spiking) in all classes of M/TCs. This excitation was frequency dependent, with short-term facilitation only at higher HDB stimulation frequency (5 Hz and above). However, frequency-dependent HDB regulation was more potent in the deeper layer M/TCs compared with more superficial layer M/TCs. In all neural circuits the balance between inhibition and excitation in local and centrifugal circuits plays a critical functional role, and this patterned input-dependent regulation of inhibitory centrifugal inputs to the olfactory bulb may help maintain the precise balance across the populations of output neurons in different environmental odors, putatively to sharpen the enhancement of tuning specificity of individual or classes of M/TCs to odors.NEW & NOTEWORTHY Neuronal local circuits in the olfactory bulb are modulated by centrifugal long circuits. In vivo study here shows that inhibitory horizontal limb of the diagonal band of Broca (HDB) modulates all five types of mitral/tufted cells (M/TCs), by direct inhibitory circuits HDB → M/TCs and indirect disinhibitory long circuits HDB → interneurons → M/TCs. The HDB net effect exerts excitation in all types of M/TCs but more powerful in deeper layer output neurons as HDB activation frequency increases, which may sharpen the tuning specificity of classes of M/TCs to odors during sensory processing.


Assuntos
Interneurônios , Bulbo Olfatório , Bulbo Olfatório/fisiologia , Bulbo Olfatório/citologia , Animais , Interneurônios/fisiologia , Camundongos , Neurônios GABAérgicos/fisiologia , Channelrhodopsins/metabolismo , Channelrhodopsins/genética , Masculino , Camundongos Endogâmicos C57BL , Potenciais de Ação/fisiologia , Inibição Neural/fisiologia , Feminino , Optogenética
2.
Mol Cancer ; 23(1): 70, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576002

RESUMO

BACKGROUND: Cellular senescence frequently occurs during anti-cancer treatment, and persistent senescent tumor cells (STCs) unfavorably promote tumor progression through paracrine secretion of the senescence-associated secretory phenotype (SASP). Extracellular vesicles (EVs) have recently emerged as a novel component of the SASP and primarily mediate the tumor-promoting effect of the SASP. Of note, the potential effect of EVs released from STCs on tumor progression remains largely unknown. METHODS: We collected tumor tissues from two cohorts of colorectal cancer (CRC) patients to examine the expression of p16, p21, and SERPINE1 before and after anti-cancer treatment. Cohort 1 included 22 patients with locally advanced rectal cancer (LARC) who received neoadjuvant therapy before surgical resection. Cohort 2 included 30 patients with metastatic CRC (mCRC) who received first-line irinotecan-contained treatment. CCK-8, transwell, wound-healing assay, and tumor xenograft experiments were carried out to determine the impacts of EVs released from STCs on CRC progression in vitro and in vivo. Quantitative proteomic analysis was applied to identify protein cargo inside EVs secreted from STCs. Immunoprecipitation and mass spectrometer identification were utilized to explore the binding partners of SERPINE1. The interaction of SERPINE1 with p65 was verified by co-immunoprecipitation, and their co-localization was confirmed by immunofluorescence. RESULTS: Chemotherapeutic agents and irradiation could potently induce senescence in CRC cells in vitro and in human CRC tissues. The more significant elevation of p16 and p21 expression in patients after anti-cancer treatment displayed shorter disease-free survival (DFS) for LARC or progression-free survival (PFS) for mCRC. We observed that compared to non-STCs, STCs released an increased number of EVs enriched in SERPINE1, which further promoted the progression of recipient cancer cells. Targeting SERPINE1 with a specific inhibitor, tiplaxtinin, markedly attenuated the tumor-promoting effect of STCs-derived EVs. Additionally, the patients with greater increment of SERPINE1 expression after anti-cancer treatment had shorter DFS for LARC or PFS for mCRC. Mechanistically, SERPINE1 bound to p65, promoting its nuclear translocation and subsequently activating the NF-κB signaling pathway. CONCLUSIONS: We provide the in vivo evidence of the clinical prognostic implications of therapy-induced senescence. Our results revealed that STCs were responsible for CRC progression by producing large amounts of EVs enriched in SERPINE1. These findings further confirm the crucial role of therapy-induced senescence in tumor progression and offer a potential therapeutic strategy for CRC treatment.


Assuntos
Neoplasias Colorretais , Vesículas Extracelulares , Neoplasias Retais , Humanos , NF-kappa B/metabolismo , Proteômica , Transdução de Sinais , Vesículas Extracelulares/metabolismo , Neoplasias Retais/metabolismo , Senescência Celular , Neoplasias Colorretais/patologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Inibidor 1 de Ativador de Plasminogênio/farmacologia
3.
Synapse ; 78(5): e22307, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39171546

RESUMO

To present the expression of calsyntenin-1 (Clstn1) in the brain and investigate the potential mechanism of Clstn1 in lithium-pilocarpine rat seizure models. Thirty-five male SD adult rats were induced to have seizures by intraperitoneal injection of lithium chloride pilocarpine. Rats exhibiting spontaneous seizures were divided into the epilepsy (EP) group (n = 15), whereas those without seizures were divided into the control group (n = 14). Evaluate the expression of Clstn1 in the temporal lobe of two groups using Western blotting, immunohistochemistry, and immunofluorescence. Additionally, 55 male SD rats were subjected to status epilepticus (SE) using the same induction method. Rats experiencing seizures exceeding Racine's level 4 (n = 48) were randomly divided into three groups: SE, SE + control lentivirus (lentiviral vector expressing green fluorescent protein [LV-GFP]), and SE + Clstn1-targeted RNA interference lentivirus (LV-Clstn1-RNAi). The LV-GFP group served as a control for the lentiviral vector, whereas the LV-Clstn1-RNAi group received a lentivirus designed to silence Clstn1 expression. These lentiviral treatments were administered via hippocampal stereotactic injection 2 days after SE induction. Seven days after SE, Western blot analysis was performed to evaluate the expression of Clstn1 in the hippocampus and temporal lobe. Meanwhile, we observed the latency of spontaneous seizures and the frequency of spontaneous seizures within 8 weeks among the three groups. The expression of Clstn1 in the cortex and hippocampus of the EP group was significantly increased compared to the control group (p < .05). Immunohistochemistry and immunofluorescence showed that Clstn1 was widely distributed in the cerebral cortex and hippocampus of rats, and colocalization analysis revealed that it was mainly co expressed with neurons in the cytoplasm. Compared with the SE group (11.80 ± 2.17 days) and the SE + GFP group (12.40 ± 1.67 days), there was a statistically significant difference (p < .05) in the latency period of spontaneous seizures (15.14 ± 2.41 days) in the SE + Clstn1 + RNAi group rats. Compared with the SE group (4.60 ± 1.67 times) and the SE + GFP group (4.80 ± 2.05 times), the SE + Clstn1 + RNAi group (2.0 ± .89 times) showed a significant reduction in the frequency of spontaneous seizures within 2 weeks of chronic phase in rats (p < .05). Elevated Clstn1 expression in EP group suggests its role in EP onset. Targeting Clstn1 may be a potential therapeutic approach for EP management.


Assuntos
Modelos Animais de Doenças , Pilocarpina , Ratos Sprague-Dawley , Convulsões , Animais , Masculino , Pilocarpina/toxicidade , Ratos , Convulsões/metabolismo , Convulsões/induzido quimicamente , Convulsões/genética , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/metabolismo , Neurocalcina/metabolismo , Neurocalcina/genética , Hipocampo/metabolismo , Cloreto de Lítio , Lobo Temporal/metabolismo , Encéfalo/metabolismo
4.
J Org Chem ; 89(17): 12681-12692, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39167724

RESUMO

An aerobic copper-catalyzed oxysulfonylation of vinylarenes with sodium sulfinates is described. This protocol features mild reaction conditions, convenient operation, and broad substrate scope with respect to vinylarenes and sodium sulfinates. Notably, the protocol demonstrates excellent tolerance of functional groups such as chloro, bromo, ester, cyano, and nitro groups. Mechanistic investigations indicated that the reaction should undergo radical cascades involving a sulfonyl radical generated from sodium sulfinate with air as the terminal oxidant, addition across alkene to deliver a benzylic radical, and subsequent cross-coupling with air.

5.
J Org Chem ; 89(14): 9755-9768, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38935873

RESUMO

A nickel-catalyzed direct sulfonylation of alkenes with sulfonyl chlorides has been developed using 1,10-phenanthroline-5,6-dione as the ligand. Unactivated alkenes and styrenes including 1,1-, 1,2-disubstituted alkenes can be subjected to the protocol, and a wide range of vinyl sulfones was obtained in high to excellent yields with good functional group compatibility. Notably, the process did not allow the desulfonylation of sulfonyl chloride or chlorosulfonylation of alkenes. Radical-trapping experiment supported that a sulfonyl free-radical was likely produced and triggered subsequent transformation in the process.

6.
Inorg Chem ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39324751

RESUMO

A unique meso Ce(III)-containing antimonotungstate, {Na(OAc)(H2O)2[Ce4(tar)(Htar)2(Sb2W21O72)2(H2O)7]}244- (Ce4tar3; H4tar = tartaric acid), consisting of two enantiomeric parts with a butterfly-like configuration, was successfully synthesized by a one-pot in situ method and characterized. The coordination of d- or l-tar ligands induced the formation of Dawson-like {Ce2Sb2W21} with right or left configurations, thereby determining the d/l configurations of {Na(OAc)(H2O)2[Ce4(tar)(Htar)2(Sb2W21O72)2(H2O)7]}22-. Carboxyl groups link these two enantiomeric parts with Ce(III) ions from each other around the symmetric center of the P1̅ space group. The three types of tar ligands exhibit distinct coordination modes, and all coordinate with at least one W(VI) atom using one carboxylate oxygen atom and one α-OH. Ce4tar3 represents the largest case among those meso-dl-tar-functionalized polyoxometalates. Furthermore, Ce4tar3 exhibits excellent catalytic activity for synthesizing isoindolinones via the three-component reaction of 2-acetylbenzoic acids, amines, and phosphine oxides.

7.
Inorg Chem ; 63(19): 8919-8924, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38698558

RESUMO

The introduction of transition metal (TM) ions into polyoxometalates (POMs) cannot only bring about interesting structural diversities but also enable changes in properties. However, TM-containing Silverton-type polyoxomolybdates are still lacking in terms of structural diversity and application development. Herein, two Zn(II)-containing Silverton-type {UMo12O42}-based polyoxomolybdates, H1.89Na4.11(H2O)9Zn[UMo12O42]·4.5H2O (Zn-1) and H1.8Na4.2(H2O)12Zn[UMo12O42] (Zn-2) were hydrothermally synthesized, demonstrating a practical strategy to assembly of TM-containing Silverton-type POMs. Zn-1 is proven to be an excellent and recyclable heterogeneous catalyst in cross-dehydrogenation coupling of 1,4-naphthoquinones with amines reactions, and a series of 2-amino-1,4-naphthoquinones with potential medicinal value have been constructed.

8.
Neurol Sci ; 45(5): 2171-2180, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38012465

RESUMO

BACKGROUND: Despite previous research suggesting a potential association between cerebral small vessel disease (CSVD) and epilepsy, the precise causality and directionality between cerebral small vessel disease (CSVD) and epilepsy remain incompletely understood. We aimed to investigate the causal link between CSVD and epilepsy. METHOD: A bidirectional two-sample Mendelian randomization (MR) analysis was performed to evaluate the causal relationship between CSVD and epilepsy. The analysis included five dimensions of CSVD, namely small vessel ischemic stroke (SVS), intracerebral hemorrhage (ICH), white matter damage (including white matter hyperintensity [WMH], fractional anisotropy, and mean diffusivity), lacunar stroke, and cerebral microbleeds. We also incorporated epilepsy encompassing both focal epilepsy and generalized epilepsy. Inverse variance weighted (IVW) was used as the primary estimate while other four MR techniques were used to validate the results. Pleiotropic effects were controlled by adjusting vascular risk factors through multivariable MR. RESULT: The study found a significant association between SVS (odds ratio [OR] 1.117, PFDR = 0.022), fractional anisotropy (OR 0.961, PFDR = 0.005), mean diffusivity (OR 1.036, PFDR = 0.004), and lacunar stroke (OR 1.127, PFDR = 0.007) with an increased risk of epilepsy. The aforementioned correlations primarily occurred in focal epilepsy rather than generalized epilepsy on subgroup analysis and retained their significance in the multivariable MR analysis. CONCLUSION: Our study demonstrated that genetic susceptibility to CSVD independently elevates the risk of epilepsy, especially focal epilepsy. Diffusion tensor imaging may help screen patients at high risk for epilepsy in CSVD. Improved management of CSVD may be a significant approach in reducing the overall prevalence of epilepsy.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Epilepsias Parciais , Epilepsia Generalizada , Epilepsia , Acidente Vascular Cerebral Lacunar , Humanos , Imagem de Tensor de Difusão , Análise da Randomização Mendeliana , Imageamento por Ressonância Magnética/métodos , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/epidemiologia , Epilepsia/diagnóstico por imagem , Epilepsia/epidemiologia , Epilepsia/genética
9.
Biomed Chromatogr ; 38(2): e5788, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38081587

RESUMO

GFH009 is a potent, highly selective, small molecule that targets and inhibits the activity of the CDK9/cyclin T1 regulatory complex of P-TEFb. This study aimed to develop and validate a highly selective and sensitive ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for precise quantification of GFH009 in rat plasma. This method was subsequently employed for conducting toxicokinetic studies of GFH009 in rats. Plasma was prepared using a simple protein precipitation method by acetonitrile. Chromatographic separation of the analytes was achieved on a BEH C18 analytical column with a rapid 3.0 min run time and a flow rate of 0.5 ml/min. The calibration curves for plasma samples exhibited excellent linearity over a wide concentration range of 1.0-1,000 ng/ml for GFH009. Intra- and inter-day accuracies were within 92.7-105.7%, and precisions were no more than 6.7%. Furthermore, the analyte demonstrated stability under four different storage conditions, with variations of <15.0%. This study pioneers a methodological innovation by introducing a highly reliable, specific and sensitive analytical method for GFH009 in rat plasma. The successful application of this method in toxicokinetic studies further underscores its significance, offering valuable insights for the methodology of clinical pharmacokinetic research.


Assuntos
Espectrometria de Massa com Cromatografia Líquida , Espectrometria de Massas em Tandem , Ratos , Animais , Espectrometria de Massas em Tandem/métodos , Ratos Sprague-Dawley , Cromatografia Líquida , Toxicocinética , Cromatografia Líquida de Alta Pressão/métodos , Inibidores de Proteínas Quinases , Reprodutibilidade dos Testes
10.
Ren Fail ; 46(1): 2283587, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38374684

RESUMO

Background: Light-chain proximal tubulopathy (LCPT) is a rare disease characterized by the accumulation of monoclonal light chains within proximal tubular cells. This study aimed to investigate the clinical characteristics of LCPT from a single Chinese nephrology referral center.Methods: Patients with kidney biopsy-proven isolated LCPT between 2016 and 2022 at Peking University First Hospital were retrospectively included. Clinical data, kidney pathological type, treatment, and prognosis were analyzed.Results: Nineteen patients were enrolled, the mean age at diagnosis was 57 ± 11 and the sex ratio was 6/13 (female/male). Mean proteinuria was 2.44 ± 1.89 g/24 hr and the mean estimated glomerular filtration rate (eGFR) at the point of biopsy was 59.640 ± 27.449 ml/min/1.73 m2. κ-restriction (84%) was dominant among LCPTs. An abnormal free light chain ratio was observed in 86% of the patients. Proximal tubulopathy with cytoplasmic inclusions accounted for the majority (53%), followed by tubulopathy associated with interstitial inflammation reaction (26%), proximal tubulopathy without cytoplasmic inclusions (16%), and proximal tubulopathy with lysosomal indigestion/constipation (5%). One patient presented with acute kidney injury and 16 patients presented with chronic kidney disease. Regarding follow-up, patients received bortezomib-based or R-CHOP chemotherapy or supportive treatment only. The mean follow-up time was 22 ± 16 months, and the mean eGFR was 63.098 ± 27.439 ml/min/1.73 m2 at the end of follow-up. These patients showed improved or stable kidney function.Conclusions: This is the first case series report of LCPT in four different pathological types in northern China. Clone-targeted chemotherapy may help preserve the kidney function in these patients.


Assuntos
Nefropatias , Nefrologia , Insuficiência Renal Crônica , Humanos , Masculino , Feminino , Estudos Retrospectivos , Túbulos Renais Proximais/patologia , Nefropatias/patologia , Rim/patologia , Insuficiência Renal Crônica/complicações
11.
J Stroke Cerebrovasc Dis ; 33(11): 107995, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39241845

RESUMO

BACKGROUND: The characteristics of patients with intracerebral hemorrhage (ICH) complicated by alcohol use disorders (AUD) are not well understood. Investigating the clinical characteristics and prognosis of this subgroup (AUD-ICH) is necessary. METHODS: This study involved young males with ICH who were admitted to our hospital between January 2013 and March 2022. Based on drinking patterns, the included cases were divided into three groups: AUD, occasional drinking, and non-drinking. We compared the clinical characteristics and prognosis of patients in the three groups. The effect of AUD on hematoma expansion and long-term dysfunction was explored by developing regression models. The potential mediating role of hematoma density heterogeneity within the relationship between AUD and hematoma expansion was examined through mediation analysis. RESULTS: This study included 222 cases of male patients with ICH, with a mean age of 54.16. AUD patients had a higher risk of hematoma expansion and dysfunction compared to occasional drinkers (odds ratio [OR] 2.966, p=0.028 for hematoma expansion; hazard ratio [HR] 2.620, p=0.006 for dysfunction) and non-drinkers (OR 3.505, p=0.011 for hematoma expansion; HR 2.795, P=0.003 for dysfunction). The mediation analysis showed that the indirect effect through hematoma density heterogeneity on the relationship between AUD and hematoma expansion was significant, with a mediated proportion of 19.3%. CONCLUSIONS: AUD was an independent risk factor for hematoma expansion and long-term dysfunction in young male patients with ICH. Hematoma density heterogeneity partially mediated the relationship between AUD and hematoma expansion.

12.
Angew Chem Int Ed Engl ; : e202410347, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39091135

RESUMO

Polyethylene oxide (PEO)-based all solid-state lithium metal batteries (ASSLMBs) are strongly hindered by the fast dendrite growth at the Li metal/electrolyte interface, especially under large rates. The above issue stems from the suboptimal interfacial chemistry and poor Li+ transport kinetics during cycling. Herein, a SnF2-catalyzed lithiophilic-lithiophobic gradient solid electrolyte interphase (SCG-SEI) of LixSny/LiF-Li2O is in-situ formed. The superior ionic LiF-Li2O rich upper layer (17.1 nm) possesses high interfacial energy and fast Li+ diffusion channels, wherein lithiophilic LixSny alloy layer (8.4 nm) could highly reduce the nucleation overpotential with lower diffusion barrier and promote rapid electron transportation for reversible Li+ plating/stripping. Simultaneously, the insoluble SnF2-coordinated PEO promotes the rapid Li+ ion transport in the bulk phase. As a result, an over 46.7 and 3.5 times improvements for lifespan and critical current density of symmetrical cells are achieved, respectively. Furthermore, LiFePO4-based ASSLMBs deliver a recorded cycling performance at 5 C (over 1000 cycles with a capacity retention of 80.0%). More importantly, impressive electrochemical performances and safety tests with LiNi0.8Mn0.1Co0.1O2 and pouch cell with LiFePO4, even under extreme conditions (i.e., 100 ℃), are also demonstrated, reconfirmed the importance of lithiophilic-lithiophobic gradient interfacial chemistry in the design of high-rate ASSLMBs for safety applications.

13.
J Neurophysiol ; 129(6): 1515-1533, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37222431

RESUMO

Mitral/tufted cells (M/TCs), the principal output neuron classes form complex circuits with bulbar neurons and long-range centrifugal circuits with higher processing areas such as the horizontal limb of the diagonal band of Broca (HDB). The precise excitability of output neurons is sculpted by local inhibitory circuits. Here, light-gated cation channel channelrhodopsin-2 (ChR2) was expressed in HDB GABAergic neurons to investigate the short-term plasticity of evoked postsynaptic currents/potentials of HDB input to all classes of M/TCs and effects on firing in the acute slice preparation. Activation of the HDB directly inhibited all classes of output neurons exhibiting frequency-dependent short-term depression of evoked inhibitory postsynaptic current (eIPSC)/potential (eIPSP), resulting in decreased inhibition of responses to olfactory nerve input as a function of input frequency. In contrast, activation of an indirect circuit of HDB→interneurons→M/TCs induced frequency-dependent disinhibition, resulting in short-term facilitation of evoked excitatory postsynaptic current (eEPSC) eliciting a burst or cluster of spiking in M/TCs. The facilitatory effects of elevated HDB input frequency were strongest on deeper output neurons (deep tufted and mitral cells) and negligible on peripheral output neurons (external and superficial tufted cells). Taken together, GABAergic HDB activation generates frequency-dependent regulation that differentially affects the excitability and responses across the five classes of M/TCs. This regulation may help maintain the precise balance between inhibition and excitation of neuronal circuits across the populations of output neurons in the face of changes in an animal sniffing rate, putatively to enhance and sharpen the tuning specificity of individual or classes of M/TCs to odors.NEW & NOTEWORTHY Neuronal circuits in the olfactory bulb closely modulate olfactory bulb output activity. Activation of GABAergic circuits from the HDB to the olfactory bulb has both direct and indirect action differentially across the five classes of M/TC bulbar output neurons. The net effect enhances the excitability of deeper output neurons as HDB frequency increases, altering the relative inhibition-excitation balance of output circuits. We hypothesize that this sharpens the tuning specificity of classes of M/TCs to odors during sensory processing.


Assuntos
Odorantes , Bulbo Olfatório , Animais , Bulbo Olfatório/fisiologia , Sensação , Potenciais Sinápticos , Nervo Olfatório
14.
Neurobiol Dis ; 181: 106096, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37001611

RESUMO

Striatal medium spiny neurons (MSNs) and striatal dopamine (DA) innervation are profoundly important for brain function such as motor control and cognition. A widely accepted theory posits that striatal DA loss causes (or leads to) MSN dendritic atrophy. However, examination of the literature indicates that the data from Parkinson's disease (PD) patients and animal PD models were contradictory among studies and hard to interpret. Here we have re-examined the potential effects of DA activity on MSN morphology or lack thereof. We found that in 15-day, 4- and 12-month old Pitx3 null mutant mice that have severe DA denervation in the dorsal striatum while having substantial residual DA innervation in the ventral striatum, MSN dendrites and spine numbers were similar in dorsal and ventral striatum, and also similar to those in normal mice. In 15-day, 4- and 12-month old tyrosine hydroxylase knockout mice that cannot synthesize L-dopa and thus have no endogenous DA in the entire brain, MSN dendrites and spine numbers were also indistinguishable from age-matched wild-type (WT) mice. Furthermore, in adult WT mice, unilateral 6-OHDA lesion at 12 months of age caused an almost complete striatal DA denervation in the lesioned side, but MSN dendrites and spine numbers were similar in the lesioned and control sides. Taken together, our data indicate that in mice, the development and maintenance of MSN dendrites and spines are DA-independent such that DA depletion does not trigger MSN dendritic atrophy; our data also suggest that the reported MSN dendritic atrophy in PD may be a component of neurodegeneration in PD rather than a consequence of DA denervation.


Assuntos
Dopamina , Doença de Parkinson , Camundongos , Animais , Dopamina/fisiologia , Neurônios/patologia , Espinhas Dendríticas/patologia , Neurônios Espinhosos Médios , Levodopa/farmacologia , Doença de Parkinson/patologia , Corpo Estriado/patologia
15.
Mol Psychiatry ; 27(11): 4754-4769, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35948662

RESUMO

Vascular cognitive impairment and dementia (VCID) is the second most common form of dementia after Alzheimer's disease (AD). Currently, the mechanistic insights into the evolution and progression of VCID remain elusive. White matter change represents an invariant feature. Compelling clinical neuroimaging and pathological evidence suggest a link between white matter changes and neurodegeneration. Our prior study detected hypoperfused lesions in mice with partial deficiency of endothelial nitric oxide (eNOS) at very young age, precisely matching to those hypoperfused areas identified in preclinical AD patients. White matter tracts are particularly susceptible to the vascular damage induced by chronic hypoperfusion. Using immunohistochemistry, we detected severe demyelination in the middle-aged eNOS-deficient mice. The demyelinated areas were confined to cortical and subcortical areas including the corpus callosum and hippocampus. The intensity of demyelination correlated with behavioral deficits of gait and associative recognition memory performances. By Evans blue angiography, we detected blood-brain barrier (BBB) leakage as another early pathological change affecting frontal and parietal cortex in eNOS-deficient mice. Sodium nitrate fortified drinking water provided to young and middle-aged eNOS-deficient mice completely prevented non-perfusion, BBB leakage, and white matter pathology, indicating that impaired endothelium-derived NO signaling may have caused these pathological events. Furthermore, genome-wide transcriptomic analysis revealed altered gene clusters most related to mitochondrial respiratory pathways selectively in the white matter of young eNOS-deficient mice. Using eNOS-deficient mice, we identified BBB breakdown and hypoperfusion as the two earliest pathological events, resulting from insufficient vascular NO signaling. We speculate that the compromised BBB and mild chronic hypoperfusion trigger vascular damage, along with oxidative stress and astrogliosis, accounting for the white matter pathological changes in the eNOS-deficient mouse model. We conclude that eNOS-deficient mice represent an ideal spontaneous evolving model for studying the earliest events leading to white matter changes, which will be instrumental to future therapeutic testing of drug candidates and for targeting novel/specific vascular mechanisms contributing to VCID and AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Demência Vascular , Substância Branca , Animais , Camundongos , Substância Branca/patologia , Óxido Nítrico/metabolismo , Circulação Cerebrovascular , Demência Vascular/patologia , Demência Vascular/psicologia , Modelos Animais de Doenças , Disfunção Cognitiva/metabolismo , Doença de Alzheimer/metabolismo
16.
PLoS Biol ; 18(9): e3000825, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32886690

RESUMO

Microbial dysbiosis in the upper digestive tract is linked to an increased risk of esophageal squamous cell carcinoma (ESCC). Overabundance of Porphyromonas gingivalis is associated with shorter survival of ESCC patients. We investigated the molecular mechanisms driving aggressive progression of ESCC by P. gingivalis. Intracellular invasion of P. gingivalis potentiated proliferation, migration, invasion, and metastasis abilities of ESCC cells via transforming growth factor-ß (TGFß)-dependent Drosophila mothers against decapentaplegic homologs (Smads)/Yes-associated protein (YAP)/Transcriptional coactivator with PDZ-binding motif (TAZ) activation. Smads/YAP/TAZ/TEA domain transcription factor1 (TEAD1) complex formation was essential to initiate downstream target gene expression, inducing an epithelial-mesenchymal transition (EMT) and stemness features. Furthermore, P. gingivalis augmented secretion and bioactivity of TGFß through glycoprotein A repetitions predominant (GARP) up-regulation. Accordingly, disruption of either the GARP/TGFß axis or its activated Smads/YAP/TAZ complex abrogated the tumor-promoting role of P. gingivalis. P. gingivalis signature genes based on its activated effector molecules can efficiently distinguish ESCC patients into low- and high-risk groups. Targeting P. gingivalis or its activated effectors may provide novel insights into clinical management of ESCC.


Assuntos
Infecções por Bacteroidaceae/complicações , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Porphyromonas gingivalis/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Aciltransferases , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Idoso , Animais , Infecções por Bacteroidaceae/metabolismo , Infecções por Bacteroidaceae/mortalidade , Infecções por Bacteroidaceae/patologia , Células Cultivadas , Progressão da Doença , Drosophila , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/microbiologia , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/microbiologia , Carcinoma de Células Escamosas do Esôfago/mortalidade , Feminino , Seguimentos , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Transdução de Sinais/fisiologia , Proteínas Smad/metabolismo , Análise de Sobrevida , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Proteínas de Sinalização YAP
17.
Acta Pharmacol Sin ; 44(11): 2282-2295, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37280363

RESUMO

Abnormalities of FGFR1 have been reported in multiple malignancies, suggesting FGFR1 as a potential target for precision treatment, but drug resistance remains a formidable obstacle. In this study, we explored whether FGFR1 acted a therapeutic target in human T-cell acute lymphoblastic leukemia (T-ALL) and the molecular mechanisms underlying T-ALL cell resistance to FGFR1 inhibitors. We showed that FGFR1 was significantly upregulated in human T-ALL and inversely correlated with the prognosis of patients. Knockdown of FGFR1 suppressed T-ALL growth and progression both in vitro and in vivo. However, the T-ALL cells were resistant to FGFR1 inhibitors AZD4547 and PD-166866 even though FGFR1 signaling was specifically inhibited in the early stage. Mechanistically, we found that FGFR1 inhibitors markedly increased the expression of ATF4, which was a major initiator for T-ALL resistance to FGFR1 inhibitors. We further revealed that FGFR1 inhibitors induced expression of ATF4 through enhancing chromatin accessibility combined with translational activation via the GCN2-eIF2α pathway. Subsequently, ATF4 remodeled the amino acid metabolism by stimulating the expression of multiple metabolic genes ASNS, ASS1, PHGDH and SLC1A5, maintaining the activation of mTORC1, which contributed to the drug resistance in T-ALL cells. Targeting FGFR1 and mTOR exhibited synergistically anti-leukemic efficacy. These results reveal that FGFR1 is a potential therapeutic target in human T-ALL, and ATF4-mediated amino acid metabolic reprogramming contributes to the FGFR1 inhibitor resistance. Synergistically inhibiting FGFR1 and mTOR can overcome this obstacle in T-ALL therapy.


Assuntos
Aminoácidos , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Humanos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Serina-Treonina Quinases TOR/metabolismo , Transdução de Sinais , Linfócitos T/metabolismo , Linhagem Celular Tumoral , Antígenos de Histocompatibilidade Menor , Sistema ASC de Transporte de Aminoácidos/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Fator 4 Ativador da Transcrição/metabolismo
18.
Can J Neurol Sci ; : 1-8, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37642011

RESUMO

OBJECTIVE: This study aimed to investigate the characteristics and prognosis of patients with alcoholic Marchiafava-Bignami disease (MBD), a rare neurological disorder commonly associated with chronic alcoholism, in Chongqing, China. METHODS: We conducted a retrospective analysis of clinical data from 21 alcoholic MBD patients treated at the First Affiliated Hospital of Chongqing University between 2012 and 2022. RESULTS: The study included 21 patients with alcoholic MBD who had a mean age of 59 ± 9.86 years and an average drinking history of 35.48 ± 8.65 years. Acute onset was observed in 14 (66.7%) patients. The primary clinical signs observed were psychiatric disorders (66.7%), altered consciousness (61.9%), cognitive disorders (61.9%), and seizures (42.9%). Magnetic resonance imaging revealed long T1 and long T2 signal changes in the corpus callosum, with lesions predominantly found in the genu (76.2%) and splenium (71.4%) of the corpus callosum. The poor prognosis group demonstrated an increased incidence of altered consciousness (100% vs 50%, P = 0.044), pyramidal signs (80% vs 18.8%, P = 0.011), and pneumonia (100% vs 31.3%, P = 0.007). Patients with a longer drinking history (45.0 ± 10.0 years vs 32.69 ± 5.99 years, p = 0.008) and a lower thiamine dose (p = 0.035) had a poorer prognosis at 1 year. CONCLUSIONS: This study identified altered consciousness, pyramidal signs, and pneumonia as predictors of a poor prognosis in patients with alcoholic MBD. A longer duration of alcohol consumption and inadequate thiamine supplementation were associated with a poorer prognosis.

19.
BMC Nephrol ; 24(1): 183, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37349681

RESUMO

BACKGROUND: The phospholipase A2 receptor (PLA2R) associated with membranous nephropathy (MN) is an organ-specific autoimmune disease associated with PLA2R and human leukocyte antigen (HLA) genes. Familial PLA2R-related MN is rarely reported. The combination of anti-GBM disease and MN has been well documented, though the mechanism behind it remains unclear. CASE PRESENTATION: We describe two siblings diagnosed with pathology-confirmed PLA2R-related MN 1 year apart. And one of the two siblings developed an anti-GBM disease. The high-resolution HLA typing showed identical alleles in both siblings, specifically heterozygotes of DRB1*15:01/*03:01. CONCLUSION: We describe a familial case of PLA2R-related MN supporting the role of genetic factors that HLA-DRB1*15:01 and DRB1*03:01 predispose patients in the development of PLA2R-related MN in the Han Chinese population. The combination of MN and anti-GBM disease may also partially be associated with the same susceptible HLA allele DRB1*15:01.


Assuntos
Doença Antimembrana Basal Glomerular , Glomerulonefrite Membranosa , Nefrite Hereditária , Humanos , Glomerulonefrite Membranosa/complicações , Glomerulonefrite Membranosa/diagnóstico , Glomerulonefrite Membranosa/genética , Irmãos , Alelos , Nefrite Hereditária/genética , Autoanticorpos
20.
BMC Neurosci ; 23(1): 54, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-36163017

RESUMO

BACKGROUND: Exercise boosts the health of some brain parts, such as the hippocampus and hypothalamus. Several studies show that long-term exercise improves spatial learning and memory, enhances hypothalamic leptin sensitivity, and regulates energy balance. However, the effect of exercise on the hippocampus and hypothalamus is not fully understood. The study aimed to find epigenetic modifications or changes in gene expression of the hippocampus and hypothalamus due to exercise. METHODS: Male C57BL/6 mice were randomly divided into sedentary and exercise groups. All mice in the exercise group were subjected to treadmill exercise 5 days per week for 1 h each day. After the 12-week exercise intervention, the hippocampus and hypothalamus tissue were used for RNA-sequencing or molecular biology experiments. RESULTS: In both groups, numerous differentially expressed genes of the hippocampus (up-regulated: 53, down-regulated: 49) and hypothalamus (up-regulated: 24, down-regulated: 40) were observed. In the exercise group, increased level of N6-methyladenosine (m6A) was observed in the hippocampus and hypothalamus (p < 0.05). Furthermore, the fat mass and obesity-associated gene (FTO) of the hippocampus and hypothalamus were down-regulated in the exercise group (p < 0.001). In addition, the Fto co-expression genes of the mouse brain were studied and analyzed using database to determine the potential roles of exercise-downregulated FTO in the brain. CONCLUSION: The findings demonstrate that long-term exercise might elevates the levels of m6A-tagged transcripts in the hippocampus and hypothalamus via down-regulation of FTO. Hence, exercise might be an effective intervention for epigenetic modification.


Assuntos
Leptina , Animais , Epigênese Genética , Hipocampo/metabolismo , Hipotálamo/metabolismo , Leptina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA/metabolismo
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