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1.
J Proteome Res ; 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39327902

ABSTRACT

Abnormal accumulation of tau protein in the brain is one pathological hallmark of Alzheimer's disease (AD). Many tau protein post-translational modifications (PTMs) are associated with the development of AD, such as phosphorylation, acetylation, and methylation. Therefore, a complete picture of the PTM landscape of tau is critical for understanding the molecular mechanisms of AD progression. Here, we offered a pilot study of combining two complementary analytical techniques, capillary zone electrophoresis (CZE)-tandem mass spectrometry (MS/MS) and reversed-phase liquid chromatography (RPLC)-MS/MS, for bottom-up proteomics of recombinant human tau-0N3R. We identified 50 phosphorylation sites of tau-0N3R in total, which is about 25% higher than that from RPLC-MS/MS alone. CZE-MS/MS provided more PTM sites (i.e., phosphorylation) and modified peptides of tau-0N3R than RPLC-MS/MS, and its predicted electrophoretic mobility helped improve the confidence of the identified modified peptides. We developed a highly efficient capillary isoelectric focusing (cIEF)-MS technique to offer a bird's-eye view of tau-0N3R proteoforms, with 11 putative tau-0N3R proteoforms carrying up to nine phosphorylation sites and lower pI values from more phosphorylated proteoforms detected. Interestingly, under native-like cIEF-MS conditions, we observed three putative tau-0N3R dimers carrying phosphate groups. The findings demonstrate that CE-MS is a valuable analytical technique for the characterization of tau PTMs, proteoforms, and even oligomerization.

2.
World J Clin Cases ; 12(26): 5960-5967, 2024 Sep 16.
Article in English | MEDLINE | ID: mdl-39286383

ABSTRACT

BACKGROUND: Gastrointestinal tract metastasis from lung cancer is rare and compared to small cell lung cancer (SCLC), non-SCLC (NSCLC) is even less likely to metastasize in this manner. Additionally, small intestinal tumors can also present with diverse complications, some of which require urgent intervention. CASE SUMMARY: In this report, we detail a unique case of stage IV lung cancer, where the presence of small intestine tumors led to intussusception. Subsequent to a small intestine resection, pathology confirmed that all three tumors within the small intestine were metastases from adenocarcinoma of the lung. The postoperative follow-up period extended beyond 14 mo. CONCLUSION: In patients with stage IV NSCLC, local tumor control can be achieved with various treatments. However, if small intestinal metastasis occurs, surgical intervention remains necessary, as it may improve survival.

3.
Sports Biomech ; : 1-15, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39212147

ABSTRACT

This study investigates the impact of chronic ankle instability (CAI) on athletes' lower extremity mechanics during bounce drop-jump landings with divided attention. Thirty Division I physical education voluntarily participated in the study. They performed two sets of bounce drop jumps: one set with a divided attention task and the other without. The obtained data were analysed using a paired t-test to compare the outcomes between the divided attention (DA) and non-divided attention (NDA) tasks. Athletes with CAI, during the DA task, displayed higher vertical landing forces, increased ankle inversion velocity, and greater range of motion of the ankle, knee, and hip in the frontal and transverse planes. They also exhibited insufficient neuromuscular preparation of the rectus femoris muscle. Notably, distinct kinematic alterations were observed in the ankle, knee, and hip joints regarding frontal and transverse lower-extremity kinematics. The findings suggest that athletes with CAI experience decreased activation of the rectus femoris muscle, which may impact their dynamic postural stability from pre-landing to ascending phases. Furthermore, the results indicate that individuals with CAI closely replicate the injury mechanisms encountered during a drop-jump landing task with divided attention. These insights offer valuable information about the real-time challenges faced by athletes with CAI.

4.
World J Gastroenterol ; 30(28): 3403-3417, 2024 Jul 28.
Article in English | MEDLINE | ID: mdl-39091717

ABSTRACT

BACKGROUND: There is currently a shortage of accurate, efficient, and precise predictive instruments for rectal neuroendocrine neoplasms (NENs). AIM: To develop a predictive model for individuals with rectal NENs (R-NENs) using data from a large cohort. METHODS: Data from patients with primary R-NENs were retrospectively collected from 17 large-scale referral medical centers in China. Random forest and Cox proportional hazard models were used to identify the risk factors for overall survival and progression-free survival, and two nomograms were constructed. RESULTS: A total of 1408 patients with R-NENs were included. Tumor grade, T stage, tumor size, age, and a prognostic nutritional index were important risk factors for prognosis. The GATIS score was calculated based on these five indicators. For overall survival prediction, the respective C-indexes in the training set were 0.915 (95% confidence interval: 0.866-0.964) for overall survival prediction and 0.908 (95% confidence interval: 0.872-0.944) for progression-free survival prediction. According to decision curve analysis, net benefit of the GATIS score was higher than that of a single factor. The time-dependent area under the receiver operating characteristic curve showed that the predictive power of the GATIS score was higher than that of the TNM stage and pathological grade at all time periods. CONCLUSION: The GATIS score had a good predictive effect on the prognosis of patients with R-NENs, with efficacy superior to that of the World Health Organization grade and TNM stage.


Subject(s)
Neoplasm Staging , Neuroendocrine Tumors , Nomograms , Rectal Neoplasms , Humans , Male , Female , Middle Aged , Rectal Neoplasms/mortality , Rectal Neoplasms/pathology , Rectal Neoplasms/therapy , Neuroendocrine Tumors/mortality , Neuroendocrine Tumors/pathology , Neuroendocrine Tumors/therapy , Neuroendocrine Tumors/diagnosis , Retrospective Studies , China/epidemiology , Prognosis , Aged , Risk Factors , Adult , ROC Curve , Progression-Free Survival , Neoplasm Grading , Risk Assessment/methods , Proportional Hazards Models , Predictive Value of Tests , Nutrition Assessment , East Asian People
5.
bioRxiv ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-39026802

ABSTRACT

Abnormal accumulation of tau proteins is one pathological hallmark of Alzheimer□s disease (AD). Many tau protein post-translational modifications (PTMs) are associated with the development of AD, such as phosphorylation, acetylation, and methylation. Therefore, a complete picture of PTM landscape of tau is critical for understanding the molecular mechanisms of AD progression. Here, we offered a pilot study of combining two complementary analytical techniques, capillary zone electrophoresis (CZE)-tandem mass spectrometry (MS/MS) and reversed-phase liquid chromatography (RPLC)-MS/MS, for bottom-up proteomics of recombinant human tau-0N3R. We identified 53 phosphorylation sites of tau-0N3R in total, which is about 30% higher than that from RPLC-MS/MS alone. CZE-MS/MS provided more PTM sites (i.e., phosphorylation) and modified peptides of tau-0N3R than RPLC-MS/MS, and its predicted electrophoretic mobility helped improve the confidence of the identified modified peptides. We developed a highly efficient capillary isoelectric focusing (cIEF)-MS technique to offer a bird's-eye view of tau-0N3R proteoforms, with 11 putative tau-0N3R proteoforms carrying up to nine phosphorylation sites and lower pI values from more phosphorylated proteoforms detected. Interestingly, under a native-like cIEF-MS condition, we observed three putative tau-0N3R dimers carrying phosphate groups. The findings demonstrate that CE-MS is a valuable analytical technique for the characterization of tau PTMs, proteoforms, and even oligomerization.

6.
Front Microbiol ; 15: 1399466, 2024.
Article in English | MEDLINE | ID: mdl-38827146

ABSTRACT

Anisakis can cause Anisakiasis in humans if raw or undercooked fish is consumed. Symptoms of infection may include vomiting, acute abdominal symptoms, or allergies. In this study, we collected 187 commercially available marine fish from the Yellow Sea, East China Sea, and South China Sea. Among them, 79 were found positive containing 520 Anisakis worms. The average prevalence rate was found 42% in this investigation. Ninety-two worms from different sea areas were selected and analyzed for identification, revealing the presence of five different species, which are Anisakis pegreffii, Hysterothylacium aduncum, Hysterothylacium zhoushanense, Hysterothylacium amoyense, and Hysterothylacium sp. In the meta-analysis, three databases: PubMed, CNKI, and BaiduXueshu were searched for surveys on the prevalence of Anisakis in Chinese waters from January 2000 to December 2023. A total of 26 studies were included in this analysis of which 25 publications were retrieved from different databases and one being the present study. The pooled prevalence of Anisakis was 45% among commercially available marine fish. Variances in the prevalence of Anisakis were noted among the four seas, with the highest rates in the East China Sea and the Bohai Sea, reaching 53% [0.38; 0.68] and 49% [0.36; 0.62], respectively. The Prevalence of Anisakis infection was significantly higher in astern parts such as Liaoning, Shanghai, and Zhejiang. Analysis of the host fish subgroups revealed that the orders of Anguilliformes, Scombriformes, and Gadiformes had high rates of infection. These findings suggest a significant prevalence of Anisakis, posing an increasing risk of infection for individuals. This study provides impactful information for implementing preventative measures against Anisakis.

7.
JCI Insight ; 9(10)2024 May 22.
Article in English | MEDLINE | ID: mdl-38775156

ABSTRACT

Since its emergence, SARS-CoV-2 has been continuously evolving, hampering the effectiveness of current vaccines against COVID-19. mAbs can be used to treat patients at risk of severe COVID-19. Thus, the development of broadly protective mAbs and an understanding of the underlying protective mechanisms are of great importance. Here, we isolated mAbs from donors with breakthrough infection with Omicron subvariants using a single-B cell screening platform. We identified a mAb, O5C2, which possesses broad-spectrum neutralization and antibody-dependent cell-mediated cytotoxic activities against SARS-CoV-2 variants, including EG.5.1. Single-particle analysis by cryo-electron microscopy revealed that O5C2 targeted an unusually large epitope within the receptor-binding domain of spike protein that overlapped with the angiotensin-converting enzyme 2 binding interface. Furthermore, O5C2 effectively protected against BA.5 Omicron infection in vivo by mediating changes in transcriptomes enriched in genes involved in apoptosis and interferon responses. Our findings provide insights into the development of pan-protective mAbs against SARS-CoV-2.


Subject(s)
Antibodies, Viral , COVID-19 , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , SARS-CoV-2/immunology , Humans , COVID-19/immunology , COVID-19/virology , Antibodies, Viral/immunology , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/chemistry , Animals , Mice , Angiotensin-Converting Enzyme 2/metabolism , Angiotensin-Converting Enzyme 2/immunology , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Cryoelectron Microscopy , Epitopes/immunology , Broadly Neutralizing Antibodies/immunology , Antibody-Dependent Cell Cytotoxicity/immunology , Female
8.
Front Vet Sci ; 11: 1403920, 2024.
Article in English | MEDLINE | ID: mdl-38784661

ABSTRACT

Background: Anisakis are globally distributed, marine parasitic nematodes that can cause human health problems, including symptoms such as vomiting, acute diarrhea, and allergic reactions. As parasitic nematodes that primarily affect the patient's digestive tract, intestinal helminths can interact directly with the host microbiota through physical contact, chemicals, or nutrient competition. It is widely accepted that the host microbiota plays a crucial role in the regulation of immunity. Materials and methods: Nematodes collected from the abdominal cavity of marine fish were identified by molecular biology and live worms were artificially infected in rats. Infection was determined by indirect ELISA based on rat serum and worm extraction. Feces were collected for 16S rDNA-based analysis of microbiota diversity. Results: Molecular biology identification based on ITS sequences identified the collected nematodes as A. pegreffii. The success of the artificial infection was determined by indirect ELISA based on serum and worm extraction from artificially infected rats. Microbiota diversity analysis showed that a total of 773 ASVs were generated, and PCoA showed that the infected group was differentiated from the control group. The control group contained five characterized genera (Prevotellaceae NK3B31 group, Turicibacter, Clostridium sensu stricto 1, Candidatus Stoquefichus, Lachnospira) and the infected group contained nine characterized genera (Rodentibacter, Christensenella, Dubosiella, Streptococcus, Anaeroplasma, Lactococcus, Papillibacter, Desulfovibrio, Roseburia). Based on the Wilcoxon test, four processes were found to be significant: bacterial secretion system, bacterial invasion of epithelial cells, bacterial chemotaxis, and ABC transporters. Conclusion: This study is the first to analyze the diversity of the intestinal microbiota of rats infected with A. pegreffii and to determine the damage and regulation of metabolism and immunity caused by the infection in the rat gut. The findings provide a basis for further research on host-helminth-microbe correlationships.

9.
Chemosphere ; 359: 142120, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38670503

ABSTRACT

Volatile organic compounds (VOCs) are crucial air pollutants in indoor environments, emitted from building materials, furniture, consumer products, cleaning products, smoking, fuel combustion, cooking, and other sources. VOCs are also emitted from human beings via breath and whole-body skin. Some VOCs cause dermal/ocular irritation as well as gastrointestinal, neurological, cardiovascular, and/or carcinogenic damage to human health. Because people spend most of their time indoors, active control of indoor VOCs has garnered attention. Phytoremediation and microbial remediation, based on plant and microorganism activities, are deemed sustainable, cost-effective, and public-friendly technologies for mitigating indoor VOCs. This study presents the major sources of VOCs in indoor environments and their compositions. Various herbaceous and woody plants used to mitigate indoor VOCs are summarized and their VOCs removal performance is compared. Moreover, this paper reviews the current state of active phytoremediation and microbial remediation for the control of indoor VOCs, and discusses future directions.


Subject(s)
Air Pollutants , Air Pollution, Indoor , Biodegradation, Environmental , Volatile Organic Compounds , Volatile Organic Compounds/analysis , Volatile Organic Compounds/metabolism , Air Pollution, Indoor/analysis , Air Pollutants/analysis , Humans , Plants/metabolism
10.
Signal Transduct Target Ther ; 9(1): 91, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38627387

ABSTRACT

Without intervention, a considerable proportion of patients with metabolism-associated fatty liver disease (MAFLD) will progress from simple steatosis to metabolism-associated steatohepatitis (MASH), liver fibrosis, and even hepatocellular carcinoma. However, the molecular mechanisms that control progressive MAFLD have yet to be fully determined. Here, we unraveled that the expression of the N6-methyladenosine (m6A) methyltransferase METTL14 is remarkably downregulated in the livers of both patients and several murine models of MAFLD, whereas hepatocyte-specific depletion of this methyltransferase aggravated lipid accumulation, liver injury, and fibrosis. Conversely, hepatic Mettl14 overexpression alleviated the above pathophysiological changes in mice fed on a high-fat diet (HFD). Notably, in vivo and in vitro mechanistic studies indicated that METTL14 downregulation decreased the level of GLS2 by affecting the translation efficiency mediated by YTHDF1 in an m6A-depedent manner, which might help to form an oxidative stress microenvironment and accordingly recruit Cx3cr1+Ccr2+ monocyte-derived macrophages (Mo-macs). In detail, Cx3cr1+Ccr2+ Mo-macs can be categorized into M1-like macrophages and S100A4-positive macrophages and then further activate hepatic stellate cells (HSCs) to promote liver fibrosis. Further experiments revealed that CX3CR1 can activate the transcription of S100A4 via CX3CR1/MyD88/NF-κB signaling pathway in Cx3cr1+Ccr2+ Mo-macs. Restoration of METTL14 or GLS2, or interfering with this signal transduction pathway such as inhibiting MyD88 could ameliorate liver injuries and fibrosis. Taken together, these findings indicate potential therapies for the treatment of MAFLD progression.


Subject(s)
NF-kappa B , Non-alcoholic Fatty Liver Disease , Animals , Humans , Mice , Down-Regulation/genetics , Liver Cirrhosis/metabolism , Macrophages/metabolism , Methyltransferases/genetics , Methyltransferases/metabolism , Myeloid Differentiation Factor 88/genetics , Myeloid Differentiation Factor 88/metabolism , NF-kappa B/genetics , NF-kappa B/metabolism , Non-alcoholic Fatty Liver Disease/metabolism , Non-alcoholic Fatty Liver Disease/pathology , Receptors, Chemokine , S100 Calcium-Binding Protein A4
11.
World J Clin Cases ; 12(9): 1622-1633, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38576744

ABSTRACT

BACKGROUND: The pathogenesis of ulcerative colitis (UC) is complex, and recent therapeutic advances remain unable to fully alleviate the condition. AIM: To inform the development of novel UC treatments, bioinformatics was used to explore the autophagy-related pathogenesis associated with the active phase of UC. METHODS: The GEO database was searched for UC-related datasets that included healthy controls who met the screening criteria. Differential analysis was conducted to obtain differentially expressed genes (DEGs). Autophagy-related targets were collected and intersected with the DEGs to identiy differentially expressed autophagy-related genes (DEARGs) associated with active UC. DEARGs were then subjected to KEGG, GO, and DisGeNET disease enrichment analyses using R software. Differential analysis of immune infiltrating cells was performed using the CiberSort algorithm. The least absolute shrinkage and selection operator algorithm and protein-protein interaction network were used to narrow down the DEARGs, and the top five targets in the Dgree ranking were designated as core targets. RESULTS: A total of 4822 DEGs were obtained, of which 58 were classified as DEARGs. SERPINA1, BAG3, HSPA5, CASP1, and CX3CL1 were identified as core targets. GO enrichment analysis revealed that DEARGs were primarily enriched in processes related to autophagy regulation and macroautophagy. KEGG enrichment analysis showed that DEARGs were predominantly associated with NOD-like receptor signaling and other signaling pathways. Disease enrichment analysis indicated that DEARGs were significantly linked to diseases such as malignant glioma and middle cerebral artery occlusion. Immune infiltration analysis demonstrated a higher presence of immune cells like activated memory CD4 T cells and follicular helper T cells in active UC patients than in healthy controls. CONCLUSION: Autophagy is closely related to the active phase of UC and the potential targets obtained from the analysis in this study may provide new insight into the treatment of active UC patients.

12.
Bioinformatics ; 40(3)2024 03 04.
Article in English | MEDLINE | ID: mdl-38379414

ABSTRACT

MOTIVATION: The process of analyzing high throughput sequencing data often requires the identification and extraction of specific target sequences. This could include tasks, such as identifying cellular barcodes and UMIs in single-cell data, and specific genetic variants for genotyping. However, existing tools, which perform these functions are often task-specific, such as only demultiplexing barcodes for a dedicated type of experiment, or are not tolerant to noise in the sequencing data. RESULTS: To overcome these limitations, we developed Flexiplex, a versatile and fast sequence searching and demultiplexing tool for omics data, which is based on the Levenshtein distance and thus allows imperfect matches. We demonstrate Flexiplex's application on three use cases, identifying cell-line-specific sequences in Illumina short-read single-cell data, and discovering and demultiplexing cellular barcodes from noisy long-read single-cell RNA-seq data. We show that Flexiplex achieves an excellent balance of accuracy and computational efficiency compared to leading task-specific tools. AVAILABILITY AND IMPLEMENTATION: Flexiplex is available at https://davidsongroup.github.io/flexiplex/.


Subject(s)
Search Engine , Software , Sequence Analysis, DNA , High-Throughput Nucleotide Sequencing , Electronic Data Processing
13.
Nat Nanotechnol ; 19(5): 632-637, 2024 May.
Article in English | MEDLINE | ID: mdl-38216685

ABSTRACT

Environmentally friendly tin (Sn) perovskites have received considerable attention due to their great potential for replacing their toxic lead counterparts in applications of photovoltaics and light-emitting diodes (LEDs). However, the device performance of Sn perovskites lags far behind that of lead perovskites, and the highest reported external quantum efficiencies of near-infrared Sn perovskite LEDs are below 10%. The poor performance stems mainly from the numerous defects within Sn perovskite crystallites and grain boundaries, leading to serious non-radiative recombination. Various epitaxy methods have been introduced to obtain high-quality perovskites, although their sophisticated processes limit the scalable fabrication of functional devices. Here we demonstrate that epitaxial heterodimensional Sn perovskite films can be fabricated using a spin-coating process, and efficient LEDs with an external quantum efficiency of 11.6% can be achieved based on these films. The film is composed of a two-dimensional perovskite layer and a three-dimensional perovskite layer, which is highly ordered and has a well-defined interface with minimal interfacial areas between the different dimensional perovskites. This unique nanostructure is formed through direct spin coating of the perovskite precursor solution with tryptophan and SnF2 additives onto indium tin oxide glass. We believe that our approach will provide new opportunities for further developing high-performance optoelectronic devices based on heterodimensional perovskites.

14.
Am J Phys Med Rehabil ; 103(7): 617-623, 2024 07 01.
Article in English | MEDLINE | ID: mdl-38207195

ABSTRACT

OBJECTIVE: Verbal instruction is one of the most commonly used methods that therapists use to correct walking pattern for people with Parkinson disease. This study aimed to compare the long-term training effects of two different verbal instructions that either asked the participants to "take big steps" or "strike the ground with the heel" on walking ability in individuals with Parkinson disease. DESIGN: Forty-five participants with Parkinson disease were randomized into the big-step or heel strike group. The participants underwent 12 sessions of treadmill and overground gait training. Throughout the interventions, the big-step group received an instruction to "take big steps," while the heel strike group received an instruction to "strike the ground with your heel." The primary outcome was gait performance, including velocity, stride length, cadence, and heel strike angle. The participants were assessed before, immediately after, and 1 mo after training. RESULTS: Both groups showed significant improvements in gait performance after training. The heel strike group showed continuous improvements in velocity and stride length during the follow-up period; however, the big-step group showed slightly decreased performance. CONCLUSIONS: A verbal instruction emphasizing heel strike can facilitate long-term retention of walking performance in people with Parkinson disease.


Subject(s)
Gait Disorders, Neurologic , Parkinson Disease , Humans , Parkinson Disease/rehabilitation , Parkinson Disease/physiopathology , Male , Female , Aged , Gait Disorders, Neurologic/rehabilitation , Gait Disorders, Neurologic/physiopathology , Gait Disorders, Neurologic/etiology , Middle Aged , Exercise Therapy/methods , Treatment Outcome , Gait/physiology , Walking/physiology
15.
Arch Gynecol Obstet ; 309(1): 287-293, 2024 01.
Article in English | MEDLINE | ID: mdl-37755532

ABSTRACT

PURPOSE: The aim of this study was to investigate the efficacy and safety of early cumulus cell removal (ECCR) during human in vitro fertilization (IVF). METHODS: A retrospective analysis was performed between January 2011 and December 2019. The study enrolled 1131 couples who underwent IVF treatment with ECCR. After propensity score matching at a 1:1 ratio, 1131 couples who underwent overnight coincubation of gametes were selected. The main outcome measure was the cumulative live birth rate. Secondary outcome measures included the cumulative pregnancy rate, polyspermy rate, available embryo rate, miscarriage rate, malformation rate, time to live birth, and oocyte-to-baby rate. RESULTS: There were no significant differences found between the two groups in the polyspermy rate, available embryo rate, miscarriage rate, time to live birth, oocyte-to-baby rate, and neonatal congenital anomalies rate. The results of the study showed that ECCR was associated with a significantly higher cumulative live birth rate and cumulative pregnancy rate, along with a significantly lower fertilization rate. CONCLUSIONS: ECCR tended to confer increased cumulative live birth rate and had no negative effect on the neonatal malformation rate.


Subject(s)
Abortion, Spontaneous , Birth Rate , Pregnancy , Female , Infant, Newborn , Humans , Pregnancy Outcome/epidemiology , Abortion, Spontaneous/epidemiology , Abortion, Spontaneous/etiology , Cohort Studies , Retrospective Studies , Cumulus Cells , Propensity Score , Fertilization in Vitro/adverse effects , Fertilization in Vitro/methods , Pregnancy Rate , Live Birth/epidemiology
16.
J Clin Invest ; 134(2)2024 Jan 16.
Article in English | MEDLINE | ID: mdl-37988169

ABSTRACT

Alzheimer's disease is characterized by the accumulation of amyloid-ß plaques, aggregation of hyperphosphorylated tau (pTau), and microglia activation. Galectin-3 (Gal3) is a ß-galactoside-binding protein that has been implicated in amyloid pathology. Its role in tauopathy remains enigmatic. Here, we showed that Gal3 was upregulated in the microglia of humans and mice with tauopathy. pTau triggered the release of Gal3 from human induced pluripotent stem cell-derived microglia in both its free and extracellular vesicular-associated (EV-associated) forms. Both forms of Gal3 increased the accumulation of pathogenic tau in recipient cells. Binding of Gal3 to pTau greatly enhanced tau fibrillation. Besides Gal3, pTau was sorted into EVs for transmission. Moreover, pTau markedly enhanced the number of EVs released by iMGL in a Gal3-dependent manner, suggesting a role of Gal3 in biogenesis of EVs. Single-cell RNA-Seq analysis of the hippocampus of a mouse model of tauopathy (THY-Tau22) revealed a group of pathogenic tau-evoked, Gal3-associated microglia with altered cellular machineries implicated in neurodegeneration, including enhanced immune and inflammatory responses. Genetic removal of Gal3 in THY-Tau22 mice suppressed microglia activation, reduced the level of pTau and synaptic loss in neurons, and rescued memory impairment. Collectively, Gal3 is a potential therapeutic target for tauopathy.


Subject(s)
Galectin 3 , Tauopathies , tau Proteins , Animals , Humans , Mice , Alzheimer Disease/pathology , Disease Models, Animal , Galectin 3/genetics , Galectin 3/metabolism , Induced Pluripotent Stem Cells/metabolism , Mice, Transgenic , Microglia/pathology , tau Proteins/genetics , tau Proteins/metabolism , Tauopathies/genetics , Tauopathies/metabolism
17.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1003774

ABSTRACT

ObjectiveTo analyze the antidepressant quality markers(Q-Marker) of Bupleuri Radix(BP) before and after vinegar-processing by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF-MS), multivariate statistical analysis and network pharmacology. MethodUPLC-Q-TOF-MS was used to analyze the chemical basis of raw and vinegar-processed products of BP, and principal component analysis(PCA) orthogonal partial least squares-discriminant analysis(OPLS-DA) were used to identify the differential components in BP that changed significantly before and after vinegar-processing, which were regarded as candidate quality markers(Q-Marker). Then the disease-drug-component-target network related to antidepressant effect of BP was constructed by network pharmacology, and the antidepressant Q-Marker of raw and vinegar-processed products of BP was determined. Rats were randomly divided into blank group, model group, fluoxetine group(2.67 mg·kg-1) and total saponin group(0.72 mg·kg-1), except the blank group, rats in the other groups were subjected to chronic unpredictable mild stress(CUMS). Three weeks after the start of modeling, rats in each administration group were given the corresponding dose of drugs once a day for 4 weeks, and rats in the blank and model groups were given normal saline with dose of 10 mL·kg-1. At 1 day before modeling, 21 days and 28 days after administration, body mass weighing, sucrose preference test and open field test were performed on each group . After 28 days of administration, real-time fluorescence quantitative polymerase chain reaction(Real-time PCR) was used to detect the mRNA expression levels of phosphatidylinositol 3-kinase(PI3K), protein kinase B(Akt), mammalian target of rapamycin(mTOR), glycogen synthase kinase-3β(GSK-3β), forkhead box transcription factor O3a(FoxO3a) and β-catenin in hippocampal tissues of rats in each group, while protein expression levels of PI3K, Akt, mTOR and FoxO3a in hippocampal tissues of rats in each group were detected by Western blot. ResultThere were 19 components in BP showed significant changes before and after vinegar-processing, and 9 components such as saikosaponin A, saikosaponin B1, saikosaponin B2, saikosaponin C and saikosaponin D were identified as potential Q-Marker through S-plot differential marker screening. Combined with the disease-drug-component-target network, saikosaponin A, saikosaponin B1, saikosaponin B2 and saikosaponin D were identified as antidepressant Q-Marker of raw and vinegar-processed products of BP. According to the results of pharmacodynamic tests, after 28 d of administration, compared with the blank group, the body mass, sucrose preference index and open field total score of rats in model group, fluoxetine group and total saponin group decreased significantly(P<0.01). Compared with the model group, the body mass, sucrose preference index and open field total score in total saponin group increased significantly(P<0.01). Compared with the blank group, mRNA expression levels of PI3K, Akt, mTOR and β-catenin in hippocampus of rats in the model group decreased significantly(P<0.05), while mRNA expression levels of GSK-3β and FoxO3a increased significantly(P<0.05). Compared with the model group, mRNA expression levels of PI3K, Akt, mTOR and β-catenin in hippocampus of rats in the total saponin group were increased significantly(P<0.05), while mRNA expression levels of GSK-3β and FoxO3a decreased significantly(P<0.05). Compared with the blank group, the protein expression levels of Akt and mTOR in hippocampus of the model group decreased significantly(P<0.01), while the protein expression levels of PI3K and FoxO3a increased significantly(P<0.01). Compared with the model group, the expression level of Akt in hippocampus of the total saponin group increased significantly(P<0.01), the mTOR expression level was increased but not statistically significant, while the protein expression levels of PI3K and FoxO3a decreased significantly(P<0.01). ConclusionThe chemical constituents of BP changed greatly after vinegar-processing, and the antidepressant Q-Marker of raw and vinegar-processed products of BP was determined by chemical basis, pharmacodynamics, network pharmacology and signaling pathway, which provided a reference for further research on quality control, pharmacodynamic substance basis and processing mechanism of BP.

18.
Mol Neurobiol ; 2023 Nov 03.
Article in English | MEDLINE | ID: mdl-37919601

ABSTRACT

Abnormal phosphorylation of the microtubule-binding protein tau in the brain is a key pathological marker for Alzheimer's disease and additional neurodegenerative tauopathies. However, how hyperphosphorylated tau causes cellular dysfunction or death that underlies neurodegeneration remains an unsolved question critical for the understanding of disease mechanism and the design of efficacious drugs. Using a recombinant hyperphosphorylated tau protein (p-tau) synthesized by the PIMAX approach, we examined how cells responded to the cytotoxic tau and explored means to enhance cellular resistance to tau attack. Upon p-tau uptake, the intracellular calcium levels rose promptly. Gene expression analyses revealed that p-tau potently triggered endoplasmic reticulum (ER) stress, unfolded protein response (UPR), ER stress-associated apoptosis, and pro-inflammation in cells. Proteomics studies showed that p-tau diminished heme oxygenase-1 (HO-1), an ER stress-associated anti-inflammation and anti-oxidative stress regulator, while stimulated the accumulation of MIOS and other proteins. p-Tau-induced ER stress-associated apoptosis and pro-inflammation are ameliorated by apomorphine, a brain-permeable prescription drug widely used to treat Parkinson's disease symptoms, and by overexpression of HO-1. Our results reveal probable cellular functions targeted by hyperphosphorylated tau. Some of these dysfunctions and stress responses have been linked to neurodegeneration in Alzheimer's disease. The observations that the ill effects of p-tau can be mitigated by a small compound and by overexpressing HO-1 that is otherwise diminished in the treated cells inform new directions of Alzheimer's disease drug discovery.

19.
ACS Chem Neurosci ; 14(21): 3913-3927, 2023 11 01.
Article in English | MEDLINE | ID: mdl-37818657

ABSTRACT

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder underlying dementia in the geriatric population. AD manifests by two pathological hallmarks: extracellular amyloid-ß (Aß) peptide-containing senile plaques and intraneuronal neurofibrillary tangles comprised of aggregated hyperphosphorylated tau protein (p-tau). However, more than half of AD cases also display the presence of aggregated α-synuclein (α-syn)-containing Lewy bodies. Conversely, Lewy bodies disorders have been reported to have concomitant Aß plaques and neurofibrillary tangles. Our drug discovery program focuses on the synthesis of multitarget-directed ligands to abrogate aberrant α-syn, tau (2N4R), and p-tau (1N4R) aggregation and to slow the progression of AD and related dementias. To this end, we synthesized 11 compounds with a triazine-linker and evaluated their effectiveness in reducing α-syn, tau isoform 2N4R, and p-tau isoform 1N4R aggregation. We utilized biophysical methods such as thioflavin T (ThT) fluorescence assays, transmission electron microscopy (TEM), photoinduced cross-linking of unmodified proteins (PICUP), and M17D intracellular inclusion cell-based assays to evaluate the antiaggregation properties and cellular protection of our best compounds. We also performed disaggregation assays with isolated Aß-plaques from human AD brains. Our results demonstrated that compound 10 was effective in reducing both oligomerization and fibril formation of α-syn and tau isoform 2N4R in a dose-dependent manner via ThT and PICUP assays. Compound 10 was also effective at reducing the formation of recombinant α-syn, tau 2N4R, and p-tau 1N4R fibrils by TEM. Compound 10 reduced the development of α-syn inclusions in M17D neuroblastoma cells and stopped the seeding of tau P301S using biosensor cells. Disaggregation experiments showed smaller Aß-plaques and less paired helical filaments with compound 10. Compound 10 may provide molecular scaffolds for further optimization and preclinical studies for neurodegenerative proteinopathies.


Subject(s)
Alzheimer Disease , Lewy Body Disease , Aged , Humans , tau Proteins/metabolism , alpha-Synuclein/metabolism , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Protein Isoforms
20.
Int J Mol Sci ; 24(19)2023 Oct 08.
Article in English | MEDLINE | ID: mdl-37834443

ABSTRACT

The P301L mutation in tau protein is a prevalent pathogenic mutation associated with neurodegenerative frontotemporal dementia, FTD. The mechanism by which P301L triggers or facilitates neurodegeneration at the molecular level remains unclear. In this work, we examined the effect of the P301L mutation on the biochemical and biological characteristics of pathologically relevant hyperphosphorylated tau. Hyperphosphorylated P301L tau forms cytotoxic aggregates more efficiently than hyperphosphorylated wildtype tau or unphosphorylated P301L tau in vitro. Mechanistic studies establish that hyperphosphorylated P301L tau exacerbates endoplasmic reticulum (ER) stress-associated gene upregulation in a neuroblastoma cell line when compared to wildtype hyperphosphorylated tau treatment. Furthermore, the microtubule cytoskeleton is severely disrupted following hyperphosphorylated P301L tau treatment. A hyperphosphorylated tau aggregation inhibitor, apomorphine, also inhibits the harmful effects caused by P301L hyperphosphorylated tau. In short, the P301L single mutation within the core repeat domain of tau renders the underlying hyperphosphorylated tau more potent in eliciting ER stress and cytoskeleton damage. However, the P301L mutation alone, without hyperphosphorylation, is not sufficient to cause these phenotypes. Understanding the conditions and mechanisms whereby selective mutations aggravate the pathogenic activities of tau can provide pivotal clues on novel strategies for drug development for frontotemporal dementia and other related neurodegenerative tauopathies, including Alzheimer's disease.


Subject(s)
Frontotemporal Dementia , Pick Disease of the Brain , Tauopathies , Mice , Animals , Humans , tau Proteins/genetics , tau Proteins/metabolism , Frontotemporal Dementia/genetics , Mice, Transgenic , Tauopathies/metabolism , Mutation , Cytoskeleton/metabolism
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