Objective To explore the mechanism of lncRNA-BC200 (BC200) targeting the ubiquitination of Beta-site APP cleaving enzyme 1 (BACE1) and regulating the repair of nerve cell injury. Methods Mouse hippocampal neuron cell line HT22 was divided into four groups: control group, oxygen-glucose deprivation/reoxygenation(OGD/R) group, OGD/R+si-NC group and OGD/R+si-BC200 group. In order to further explore the relationship between BC200 and BACE1, HT22 cells were divided into four groups: OGD/R group, OGD/R+si-BC200 group, OGD/R+si-BC200+NC group and OGD/R+si-BC200+ BACE1 group. Twenty male C57BL/6J mice were randomly assigned to the following four groups: control group, middle cerebral artery occlusion (MCAO) group, MCAO+si-BC200 group and MCAO+si-BC200+BACE1 group. The mRNA expression levels of BC200 and BACE1 in cells were measured by real-time quantitative reverse transcription polymerase chain reaction. The expressions of c-caspase-3, B-cell lymphoma 2 (Bcl2), Bcl2 associated X protein(BAX) and BACE1 were detected by western blot, and the apoptotic cells were detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) test. Results Compared with the control group, the activity of HT22 cells in OGD/R group decreased significantly, and the percentage of apoptotic cells increased significantly. Compared with OGD/R+si-NC group, the activity of HT22 cells in OGD/R+si-BC200 group increased significantly, and the percentage of apoptotic cells decreased significantly. Compared with the control group, the expression of BACE1 protein in HT22 cells in OGD/R group was significantly enhanced. Compared with OGD/R+si-NC group, the expression of BACE1 protein in HT22 cells in OGD/R+si-BC200 group decreased significantly. It was observed that after OGD/R treatment, the ubiquitination level of BACE1 decreased significantly and the expression of BACE1 protein increased significantly. After transfection with si-BC200, the ubiquitination level of BACE1 protein increased significantly, while the expression of BACE1 protein decreased significantly. Compared with OGD/R+si-BC200+NC group, the percentage of apoptotic cells, the expression of c-caspase-3 and Bax protein in HT22 cells in OGD/R+si-BC200+BACE1 group increased significantly, and the expression of Bcl2 protein decreased significantly. Compared with the control group, the number of cerebral infarction areas and TUNEL positive cells in MCAO group increased significantly, and the survival number of neurons decreased significantly. Compared with the MCAO group, the number of cerebral infarction areas and TUNEL positive cells in MCAO+si-BC200 group decreased significantly, and the survival number of neurons increased significantly, while the addition of BACE1 reversed the improvement of si-BC200 transfection. Conclusion The combination of BC200 and BACE1 inhibit the ubiquitination of BACE1, and participate in mediating the expression enhancement of BACE1 induced by OGD/R. Specific blocking of BC200/BACE1 axis may be a potential therapeutic target to protect neurons from apoptosis induced by cerebral ischemia/reperfusion.
Animals ; Amyloid Precursor Protein Secretases/genetics* ; RNA, Long Noncoding/physiology* ; Aspartic Acid Endopeptidases/genetics* ; Male ; Neurons/pathology* ; Mice ; Mice, Inbred C57BL ; Apoptosis/genetics* ; Ubiquitination ; Cell Line ; Hippocampus/metabolism* ; bcl-2-Associated X Protein/genetics* ; Caspase 3/genetics* ; Infarction, Middle Cerebral Artery/metabolism*

Alzheimer's disease (AD), a neurodegenerative disorder with complex etiologies, manifests through a cascade of pathological changes before clinical symptoms become apparent. Among these early changes, alterations in the expression of non-coding RNAs (ncRNAs) have emerged as pivotal events. In this study, we focused on the aberrant expression of ncRNAs and revealed that Lamr1-ps1, a pseudogene of the laminin receptor, significantly exacerbates early spatial learning and memory deficits in APP/PS1 mice. Through a combination of bioinformatics prediction and experimental validation, we identified the miR-29c/Bace1 pathway as a potential regulatory mechanism by which Lamr1-ps1 influences AD pathology. Importantly, augmenting the miR-29c-3p levels in mice ameliorated memory deficits, underscoring the therapeutic potential of targeting miR-29c-3p in early AD intervention. This study not only provides new insights into the role of pseudogenes in AD but also consolidates a foundational basis for considering miR-29c as a viable therapeutic target, offering a novel avenue for AD research and treatment strategies.
Animals ; Alzheimer Disease/pathology* ; Pseudogenes/genetics* ; Mice ; Memory Disorders/metabolism* ; MicroRNAs/genetics* ; Disease Models, Animal ; Spatial Learning/physiology* ; Mice, Transgenic ; Presenilin-1/genetics* ; Male ; Amyloid Precursor Protein Secretases/metabolism* ; Mice, Inbred C57BL ; Aspartic Acid Endopeptidases/metabolism*

Physalin B (PB), one of the major active steroidal constituents of Solanaceae Physalis plants, has a wide variety of biological activities. We found that PB significantly down-regulated β-amyloid (Aβ) secretion in N2a/APPsw cells. However, the underlying mechanisms are not well understood. In the current study, we investigated the changes in key enzymes involved in β-amyloid precursor protein (APP) metabolism and other APP metabolites by treating N2a/APPsw cells with PB at different concentrations. The results indicated that PB reduced Aβ secretion, which was caused by down-regulation of β-secretase (BACE1) expression, as indicated at both the protein and mRNA levels. Further research revealed that PB regulated BACE1 expression by inducing the activation of forkhead box O1 (FoxO1) and inhibiting the phosphorylation of signal transducer and activator of transcription 3 (STAT3). In addition, the effect of PB on BACE1 expression and Aβ secretion was reversed by treatment with FoxO1 siRNA and STAT3 antagonist S3I-201. In conclusion, these data demonstrated that PB can effectively down-regulate the expression of BACE1 to reduce Aβsecretion by activating the expression of FoxO1 and inhibiting the phosphorylation of STAT3.
Alzheimer Disease ; Amyloid Precursor Protein Secretases/metabolism* ; Amyloid beta-Peptides/metabolism* ; Aspartic Acid Endopeptidases/metabolism* ; Down-Regulation ; Forkhead Box Protein O1/genetics* ; Humans ; Phosphorylation ; STAT3 Transcription Factor/metabolism* ; Secosteroids

BACKGROUNDAmyloid β (Aβ) has been established as a key factor for the pathological changes in the brains of patients with Alzheimer's disease (AD), and cellular senescence is closely associated with aging and cognitive impairment. However, it remains blurred whether, in the AD brains, Aβ accelerates the neuronal senescence and whether this senescence, in turn, impairs the cognitive function. This study aimed to explore the expression of senescence-associated genes in the hippocampal tissue from young to aged 5XFAD mice and their age-matched wild type (WT) mice to determine whether senescent neurons are present in the transgenic AD mouse model.

METHODSThe 5XFAD mice and age-matched wild type mice, both raised from 1 to 18 months, were enrolled in the study. The senescence-associated genes in the hippocampus were analyzed and differentially expressed genes (DEGs) were screened by quantitative real-time polymerase chain reaction. Cognitive performance of the mice was evaluated by Y-maze and Morris water maze tests. Oligomeric Aβ (oAβ) (1-42) was applied to culture primary neurons to simulate the in vivo manifestation. Aging-related proteins were detected by Western blotting analysis and immunofluorescence.

RESULTSIn 5XFAD mice, of all the DEGs, the senescence-associated marker p16 was most significantly increased, even at the early age. It was mainly localized in neurons, with a marginal expression in astrocytes (labeled as glutamine synthetase), nil expression in activated microglia (labeled as Iba1), and negatively correlated with the spatial cognitive impairments of 5XFAD mice. oAβ (1-42) induced the production of senescence-related protein p16, but not p53 in vitro, which was in line with the in vivo manifestation.

CONCLUSIONSoAβ-accelerated neuronal senescence may be associated with the cognitive impairment in 5XFAD mice. Senescence-associated marker p16 can serve as an indicator to estimate the cognitive prognosis for AD population.

Alzheimer Disease ; metabolism ; physiopathology ; Amyloid Precursor Protein Secretases ; genetics ; metabolism ; Amyloid beta-Peptides ; metabolism ; Amyloid beta-Protein Precursor ; metabolism ; Animals ; Aspartic Acid Endopeptidases ; genetics ; metabolism ; Brain ; metabolism ; physiopathology ; Cells, Cultured ; Cellular Senescence ; genetics ; physiology ; Cognition ; physiology ; Cognition Disorders ; metabolism ; physiopathology ; Disease Models, Animal ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Transgenic ; Neurons ; metabolism ; pathology ; Real-Time Polymerase Chain Reaction

OBJECTIVETo study the clinicopathologic characteristics of primary salivary gland-type lung carcinomas, and the immunophenotypic value of TTF-1, Napsin A and Ki-67 in their differential diagnosis.

METHODSTotally 48 special type lung cancer surgical removal specimens were collected in China-Japan Friendship Hospital during September 2009 to December 2014. A panel of immunohistochemical markers (TTF-1, Napsin A, Ki-67, CK5/6, CK7 and p63) were conducted on these specimens.

RESULTSThe 48 cases of special type lung cancer included 25 cases of primary salivary gland-type lung carcinoma (18 cases of adenoid cystic carcinoma and 7 cases of mucoepidermoid carcinoma), 5 cases pulmonary adenocarcinoma with mucoepidermoid carcinoma-like or adenoid cystic carcinoma-like structure, and 18 cases of pulmonary adenosquamous carcinoma. Compared with pulmonary adenocarcinoma with mucoepidermoid carcinoma-like or adenoid cystic carcinoma-like structure and pulmonary adenosquamous carcinoma, primary salivary gland-type lung carcinomas have special characteristics in median age, sex, location, tumor size, LN involvement and pleura invasion, with negative TTF-1 and Napsin A expression as well as lower Ki-67 index detected by immunohistochemistry. Primary salivary gland-type lung carcinomas usually have an indolent behavior.

CONCLUSIONSPrimary salivary gland-type lung carcinomas are low-aggressive entities. The origins of primary salivary gland-type lung carcinomas were different from that of pulmonary adenocarcinoma with mucoepidermoid carcinoma-like or adenoid cystic carcinoma-like structure and pulmonary adenosquamous carcinoma. Negative TTF-1 and Napsin A expression as well as Ki-67 index lower than 20% have special value for primary salivary gland-type lung carcinomas in their differential diagnosis.

Adenocarcinoma ; diagnosis ; Aspartic Acid Endopeptidases ; metabolism ; Biomarkers, Tumor ; metabolism ; Carcinoma, Adenoid Cystic ; diagnosis ; Carcinoma, Mucoepidermoid ; diagnosis ; China ; DNA-Binding Proteins ; metabolism ; Humans ; Immunohistochemistry ; Ki-67 Antigen ; metabolism ; Lung Neoplasms ; diagnosis ; Transcription Factors

OBJECTIVETo investigate the value of detecting thyroid transcription factor 1 (TTF-1) and Noval aspartic proteinase of pepsin family A (napsin A) in pleural fluid cell blocks in cytopathologic diagnosis of pulmonary adenocarcinoma.

METHODSConventional cell smears of pleural effusions were obtained from 48 patients with a history of lung adenocarcinoma for cytological analysis. The cell blocks were prepared using the cytological specimens and examined with immunohistochemistry for TTF-1 and napsin A. The rates of a positive diagnosis of pulmonary adenocarcinoma were compared between the two methods, and the diagnositic value of TTF-1 and napsin A in pleural fluid cell blocks was evaluated.

RESULTSImmuno- histochemistry of the cell block sections yielded a significantly higher positive rate of diagnosis than cytological analysis of conventional cell smear (84.44% vs 55.56%, P<0.05). Most of the pleural fluid cell blocks showed positive expressions of TTF-1 (36/38, 94.74%) and napsin A (30/38, 78.95%), and none of samples showed TTF-1 or napsin A expression in the mesothelial cells (P<0.05). The combination detection of TTF-1 and napsin A in pleural fluid cell blocks had a high diagnosis value with a diagnostic sensitivity of 97.37% and a specificity of 100% for pulmonary adenocarcinoma.

CONCLUSIONSThe combined detection of TTF-1 and napsin A in pleural fluid cell blocks facilitates cytopathologic diagnosis of pulmonary adenocarcinoma.

Adenocarcinoma ; diagnosis ; metabolism ; Aspartic Acid Endopeptidases ; metabolism ; Biomarkers, Tumor ; metabolism ; Humans ; Immunohistochemistry ; Lung Neoplasms ; diagnosis ; metabolism ; Nuclear Proteins ; metabolism ; Pleural Effusion ; Sensitivity and Specificity ; Thyroid Nuclear Factor 1 ; Transcription Factors ; metabolism

OBJECTIVETo investigate the effects of exogenous hydrogen sulfide (H2S) on β-site APP cleaving enzyme 1 (BACE-1) and β-amyloid peptide (Aβ) metabolism in primary culture of neurons under high-glucose condition.

METHODSThe cortical neurons in primary culture under normal and high glucose (60 mmol/L) conditions for 24 h were exposed to 25, 50 and 100 µmol/L NaHS. Aβ1-42 concentration in the cell culture was measured by ELISA, and BACE-1 mRNA and protein levels were detected by fluorescent quantitative real-time PCR and Western blotting, respectively.

RESULTSCompared with the neurons cultured in normal glucose, the neurons exposed to high glucose showed significantly increased Aβ1-42 concentration and BACE-1 mRNA and protein expressions (P<0.05). Exposure to 25, 50 and 100 µmol/L NaHS significantly decreased Aβ1-42 concentration and BACE-1 mRNA and protein expressions in the high-glucose cell culture (P<0.05).

CONCLUSIONNeurons exposed to high glucose exhibit increased Aβ1-42 levels and BACE-1 mRNA and protein expressions, which can be concentration-dependently decreased by NaHS.

Amyloid Precursor Protein Secretases ; metabolism ; Amyloid beta-Peptides ; metabolism ; Animals ; Aspartic Acid Endopeptidases ; metabolism ; Cells, Cultured ; Culture Media ; chemistry ; Glucose ; chemistry ; Hydrogen Sulfide ; pharmacology ; Neurons ; drug effects ; metabolism ; Peptide Fragments ; metabolism ; Rats ; Rats, Sprague-Dawley

To investigate the role and possible molecular mechanism of astrocytes in inflammation and amyloid β-protein (Aβ) formation, in this research, by using LPS to stimulate cultured rat astrocytes in vitro with or without anti-Toll-like receptor 4 (TLR4) antibody pretreatment, we first detected the TLR4, TNF-α, IL-1β, β-amyloid precursor protein (β-APP) and β-site APP clearing enzyme 1 (BACE1) mRNA with real-time PCR, and TLR4, NF-κB/P65 protein in cultured astrocytes by Western blot, and then further probed the translocation of NF-κB/P65 using immunofluorescence and the contents of TNF-α, IL-1β and Aβ in culture supernatant through ELISA. We found that all of these indexes increased at different degrees after LPS-stimulation. However, if pretreatment with anti- TLR4 antibody, such stimulating effects of LPS on the nuclear translocation of NF-κB/P65 and TNF-α, IL-1β, Aβ contents in astrocytic culture supernatant were reduced significantly or disappeared in comparison with the group with only LPS-administration. Our results suggest that TLR4 in astrocytes might play an important role in the inflammation and Aβ formation through the TLR4/NF-κB signaling pathway, thus providing new knowledge and understanding of the inflammatory hypothesis of AD pathogenesis.
Amyloid Precursor Protein Secretases ; metabolism ; Amyloid beta-Protein Precursor ; metabolism ; Animals ; Aspartic Acid Endopeptidases ; metabolism ; Astrocytes ; metabolism ; Cells, Cultured ; Cerebral Cortex ; cytology ; Inflammation ; metabolism ; Interleukin-1beta ; metabolism ; RNA, Messenger ; Rats ; Real-Time Polymerase Chain Reaction ; Signal Transduction ; Toll-Like Receptor 4 ; metabolism ; Transcription Factor RelA ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo explore the effect of Panax notoginseng saponin (PNS) on the activity and content of beta-secretase in the brain of senescence accelerated mouse-prone 8 (SAMP8) mice with Alzheimer's disease.

METHODSTotally 32 SAMP8 mice were randomly divided into the normal control group, the high dose PNS group (200 mg/kg), the low dose group (100 mg/kg), and the huperzine A group (0.3 mg/kg), 8 in each group. Equal volume of double distilled water was given to those in the normal control group. All medication was given by gastrogavage, once daily for two successive months. The activity of BACE1 was assayed by direct immunofluorescent method (DIF). The content of BACE1 protein was detected by Western blot.

RESULTSThe relative fluorescence units (RFU/microg) was 2.008 +/- 0.031 in the high dose PNS group, 2.221 +/- 0.029 in the low dose PNS group, and 2.267 +/- 0.076 in the huperzine A group, all lower than that in the normal control group (2.403 +/- 0.058; all P < 0.01). The content of BACE1 protein was 0.900 +/- 0.028 in the high dose PNS group, 1.000 +/- 0.032 in the low dose PNS group, and 0.837 +/- 0.080 in the huperzine A group, all lower than that in the normal control group (2.210 +/- 0.074, all P < 0.01).

CONCLUSIONPNS higher than 100 mg/kg could decrease the activity of BACE1 and down-regulate the content of BACE1 protein in the brain of SAMP8 mice.

Aging ; Alzheimer Disease ; metabolism ; Amyloid Precursor Protein Secretases ; metabolism ; Animals ; Aspartic Acid Endopeptidases ; metabolism ; Brain ; metabolism ; Disease Models, Animal ; Male ; Mice ; Panax notoginseng ; RNA, Messenger ; genetics ; Saponins ; pharmacology

OBJECTIVETo study the effects of Huannao Yicong Recipe (HNYCR)extract on the learning and memory ability, and the expressions of amyloid precursor protein (APP), beta-site APP-cleaving enzyme 1 (BACE1), presenilin-1 (PS-1), and beta amyloid protein (Abeta)in hippocampus CA1 area of APP transgenic mice, and to explore its mechanisms for treating Alzheimer's disease (AD).

METHODSTotally 3-month-old APP695V7171 transgenic mice were used to establish the AD model in this research. They were randomly divided into the model group, the Donepezil group, the large dose HNYCR extract group, the small dose HNYCR extract group, and the normal control group (C57BL/6J mice), 15 in each group. These animals were gavaged for 4 continuous months. Relevant indicators were detected: Morris water maze test was used to measure the spatial learning and memory ability. The immunohistochemical assay was used to detect the expressions of APP, BACE1, PS-1, and Abeta.

RESULTSThe times of crossing the original platform and the swimming time and distance in the fourth quadrant of the 7-month-old APP transgenic mice were significantly reduced in Morris water maze test, when compared with the normal control group (P < 0.01). The times of crossing original platform and the swimming time and distance in the fourth quadrant of all treatment groups significantly increased in Morris water maze test, when compared with the model group (P < 0.05). The expressions of APP, BACE1, PS-1, and Abeta in hippocampus CA1 area of 7-month-old model mice increased significantly (P < 0.01), when compared with the normal control group. The expressions of APP, BACE1, PS-1, and Abeta in each 7-month-old intervention groups were significantly reduced, when compared with the model group (P < 0.01).

CONCLUSIONEarly application of HNYCR extract can obviously improve the learning and memory ability of APP transgenic mice that has declined, reduce the expressions of APP, BACE1, PS-1, and Abeta in the hippocampal CA1 area, reduce the production of Abeta, and slow down the pathological process of brains in APP transgenic mice.

Alzheimer Disease ; metabolism ; Amyloid Precursor Protein Secretases ; genetics ; metabolism ; Amyloid beta-Peptides ; genetics ; metabolism ; Amyloid beta-Protein Precursor ; genetics ; metabolism ; Animals ; Aspartic Acid Endopeptidases ; genetics ; metabolism ; Brain ; drug effects ; metabolism ; CA1 Region, Hippocampal ; drug effects ; metabolism ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; Female ; Male ; Maze Learning ; drug effects ; Memory ; drug effects ; Mice ; Mice, Inbred C57BL ; Mice, Transgenic ; Presenilin-1 ; genetics ; metabolism