The accumulation and spread of prion-like proteins is a key feature of neurodegenerative diseases (NDs) such as Alzheimer's disease, Parkinson's disease, or Amyotrophic Lateral Sclerosis. In a process known as 'seeding', prion-like proteins such as amyloid beta, microtubule-associated protein tau, α-synuclein, silence superoxide dismutase 1, or transactive response DNA-binding protein 43 kDa, propagate their misfolded conformations by transforming their respective soluble monomers into fibrils. Cellular and molecular evidence of prion-like propagation in NDs, the clinical relevance of their 'seeding' capacities, and their levels of contribution towards disease progression have been intensively studied over recent years. This review unpacks the cyclic prion-like propagation in cells including factors of aggregate internalization, endo-lysosomal leaking, aggregate degradation, and secretion. Debates on the importance of the role of prion-like protein aggregates in NDs, whether causal or consequent, are also discussed. Applications lead to a greater understanding of ND pathogenesis and increased potential for therapeutic strategies.
Humans ; Prions ; Neurodegenerative Diseases/pathology* ; Amyloid beta-Peptides ; Alzheimer Disease ; alpha-Synuclein ; tau Proteins ; Parkinson Disease

Extracellular deposition of β-amyloid (Aβ) and intracellular hyperphosphorylated tau are the predominant pathological changes in Alzheimer's disease (AD). Increasing evidence demonstrates a critical role of a variety of small GTPases, namely Ras-related proteins (Rabs), in the pathogenesis of AD. As crucial regulators of intracellular membrane trafficking, alteration in Rab protein expression and function represents one of the primary factors contributing to the abnormal membrane trafficking in AD. Additionally, the Rab GTPases are also involved in the development of Aβ, tau and other pathological changes associated with AD. In this article, we conduct a comprehensive review on the primary functions of multiple Rab proteins and their involvement in the pathogenesis of AD.
Humans ; Alzheimer Disease ; rab GTP-Binding Proteins/metabolism* ; Amyloid beta-Peptides/metabolism* ; tau Proteins/metabolism*

This study aims to explore the effect and mechanism of Danggui Buxue Decoction(DBD)-containing serum in alleviating the H9c2 cell injury caused by the exposure to intermittent low oxygen. H9c2 cells were assigned into five groups: control(CON) group, intermittent low oxygen(IH) group, intermittent low oxygen plus DBD-containing serum(IH+DBD) group, intermittent low oxygen plus the autophagy enhancer rapamycin(IH+RAPA) group, and intermittent low oxygen plus DBD-containing serum and the autophagy inhibitor 3-methyladenine(IH+DBD+3-MA) group. Monodansylcadaverine(MDC) staining was employed to detect the changes of autophagosomes. Cell counting kit-8(CCK-8) assay was employed to determine the activity of myocardial cells, and lactate dehydrogenase(LDH) and creatine kinase(CK) kits were used to measure the LDH and CK levels in the cell culture, which would reflect the degree of cell damage. TdT-mediated dUTP nick-end labeling(TUNEL) staining was used to detect the apoptosis of myocardial cells, and JC-1 fluorescence probe to detect the changes in mitochondrial membrane potential. Western blot was employed to determine the expression levels of the autophagy-related proteins microtubule-associated proteins light chain 3Ⅱ(LC3Ⅱ), microtubule-associated proteins light chain 3Ⅰ(LC3Ⅰ), P62, Parkin and apoptosis related proteins pro caspase-3, caspase-3, B-cell lymphoma-2(Bcl-2), Bcl-2-associated X(Bax). The results showed that compared with the CON group, the IH group showed decreased fluorescence intensity of MDC staining, decreased LC3Ⅱ/LC3Ⅰ ratio, down-regulated Parkin expression, and up-regulated expression of P62. In addition, the IH group showed decreased cell survival rate, increased content of LDH and CK in the culture medium, increased number of TUNEL positive cells, and decreased pro caspase-3/caspase-3 and Bcl-2/Bax ratios and mitochondrial membrane potential. Compared with the IH group, the IH+DBD and IH+RAPA groups showed increased fluorescence intensity of MDC staining, increased LC3Ⅱ/LC3Ⅰ ratio, up-regulated Parkin expression, and down-regulated P62 expression. In addition, the two groups showed increased cell survival rate, reduced content of LDH and CK in the culture medium, decreased number of TUNEL positive cells, and increased pro caspase-3/caspase-3 and Bcl-2/Bax ratios and mitochondrial membrane potential. The IH+DBD+3-MA and IH groups showed no significant differences in the above indicators. Compared with the IH+DBD group, the IH+DBD+3-MA group showed decreased fluorescence intensity of MDC staining, decreased LC3Ⅱ/LC3Ⅰ ratio, down-regulated Parkin expression, and up-regulated P62 expression. In addition, the group had decreased cell survival rate, increased content of LDH and CK in the culture medium, increased number of TUNEL positive cells, decreased pro caspase-3/caspase-3 and Bcl-2/Bax ratios, and declined mitochon-drial membrane potential. To sum up, DBD could promote the mitophagy, inhibit the apoptosis, and alleviated the injury of H9c2 cells exposed to low oxygen.
Oxygen ; bcl-2-Associated X Protein/metabolism* ; Caspase 3/genetics* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Apoptosis ; Autophagy ; Ubiquitin-Protein Ligases ; Microtubule-Associated Proteins

BACKGROUND: Lung adenocarcinoma (LUAD) is a major subtype of lung cancer, and its treatment and diagnosis remain a hot research topic. Targeting protein for Xenopus kinesin-like protein 2 (TPX2) is highly expressed in a variety of cancer cells and may be associated with the progression of LUAD. This study aimed to investigate the effect of TPX2 on the malignant progression of LUAD cells and the regulatory mechanisms. METHODS: The expression of gene TPX2 in LUAD tissues from The Cancer Genome Atlas (TCGA) database was analyzed by bioinformatics analysis techniques. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression levels of TPX2 and miR-218-5p in human lung normal cell lines and human LUAD cell lines. Western blot was used to detect TPX2 protein expression in cell lines and its effect on the expression of key proteins in the p53 signaling pathway. The relationship between TPX2 and miR-218-5p was predicted using bioinformatics and verified by dual luciferase reporter gene assay. Cell counting kit-8 (CCK-8) assay, cell clone formation, cell scratching, Transwell assay, and flow cytometry were used to detect the effects of miR-218-5p and TPX2 on LUAD cell function. RESULTS: TPX2 was significantly overexpressed in LUAD cells, and knockdown of TPX2 inhibited LUAD cell proliferation, migration, and invasion, promoted apoptosis and induced G2/M phase block, and promoted the expression of key proteins in the p53 signaling pathway. miR-218-5p, an upstream regulator of TPX2, could inhibit its expression. Overexpression of miR-218-5p eliminated the malignant development caused by high expression of TPX2, inhibited the malignant processes of LUAD cells such as proliferation and migration as well as promoted the p53 signaling pathway. CONCLUSIONS miR-218-5p targets and inhibits TPX2 expression and exerts an inhibitory effect on the malignant progression of LUAD cells via p53.
Humans ; Lung Neoplasms/genetics* ; Tumor Suppressor Protein p53/genetics* ; Adenocarcinoma of Lung/genetics* ; Adenocarcinoma/genetics* ; Cell Proliferation/genetics* ; MicroRNAs/genetics* ; Cell Movement/genetics* ; Gene Expression Regulation, Neoplastic ; Cell Line, Tumor ; Microtubule-Associated Proteins/genetics* ; Cell Cycle Proteins/genetics*

Rats ; Animals ; Okadaic Acid/toxicity* ; PC12 Cells ; Triterpenes ; tau Proteins/metabolism* ; Phosphorylation

OBJECTIVE: To observe the effects of <i>Yizhi Tiaosheni> (benefiting mental health and regulating the spirit) acupuncture on learning and memory function, and the expression of phosphorylated tubulin-associated unit (tau) protein in the hippocampus of Alzheimer's disease (AD) model rats, and explore the effect mechanism of this therapy on AD. METHODS: A blank group and a sham-operation group were randomly selected from 60 male SD rats, 10 rats in each one. AD models were established in the rest 40 rats by the intraperitoneal injection of D-galactose and okadaic acid in the CA1 region of the bilateral hippocampus. Thirty successfully-replicated model rats were randomly divided into a model group, a western medication group and an acupuncture group, 10 rats in each one. In the acupuncture group, acupuncture was applied to "Baihui" (GV 20), "Sishencong" (EX-HN 1), "Neiguan" (PC 6), "Shenmen" (HT 7), "Xuanzhong" (GB 39) and "Sanyinjiao" (SP 6); and the needles were retained for 10 min. Acupuncture was given once daily. One course of treatment was composed of 6 days, with the interval of 1 day; the completion of treatment included 4 courses. In the western medication group, donepezil hydrochloride solution (0.45 mg/kg) was administrated intragastrically, once daily; it took 7 days to accomplish one course of treatment and a completion of intervention was composed of 4 courses. Morris water maze (MWM) and novel object recognition test (NORT) were used to assess the learning and memory function of the rats. Using HE staining and Nissl staining, the morphological structure of the hippocampus was observed. With Western blot adopted, the protein expression of the tau, phosphorylated tau protein at Ser198 (p-tau Ser198), protein phosphatase 2A (PP2A) and glycogen synthase kinase-3β (GSK-3β) in the hippocampus was detected. RESULTS: There were no statistical differences in all of the indexes between the sham-operation group and the blank group. Compared with the sham-operation group, in the model group, the MWM escape latency was prolonged (<i>Pi><0.05), the crossing frequency and the quadrant stay time in original platform were shortened (<i>Pi><0.05), and the NORT discrimination index (DI) was reduced (<i>Pi><0.05); the hippocampal cell numbers were declined and the cells arranged irregularly, the hippocampal neuronal structure was abnormal and the numbers of Nissl bodies decreased; the protein expression of p-tau Ser198 and GSK-3βwas increased (<i>Pi><0.05) and that of PP2A decreased (<i>Pi><0.05). When compared with the model group, in the western medication group and the acupuncture group, the MWM escape latency was shortened (<i>Pi><0.05), the crossing frequency and the quadrant stay time in original platform were increased (<i>Pi><0.05), and DI got higher (<i>Pi><0.05); the hippocampal cell numbers were elevated and the cells arranged regularly, the damage of hippocampal neuronal structure was attenuated and the numbers of Nissl bodies were increased; the protein expression of p-tau Ser198 and GSK-3β was reduced (<i>Pi><0.05) and that of PP2A was increased (<i>Pi><0.05). There were no statistically significant differences in the above indexes between the acupuncture group and the western medication group (<i>Pi>>0.05). CONCLUSION Acupuncture therapy of "benefiting mental health and regulating the spirit" could improve the learning and memory function and alleviate neuronal injure of AD model rats. The effect mechanism of this therapy may be related to the down-regulation of GSK-3β and the up-regulation of PP2A in the hippocampus, and then to inducing the inhibition of tau protein phosphorylation.
Male ; Animals ; Rats ; Rats, Sprague-Dawley ; Glycogen Synthase Kinase 3 beta ; Tubulin ; Alzheimer Disease/therapy* ; tau Proteins/genetics* ; Acupuncture Therapy ; Hippocampus

The present study investigated the mechanism of the Tibetan patent medicine Ershiwuwei Shanhu Pills(ESP) in alleviating Alzheimer's disease in mice via Akt/mTOR/GSK-3β signaling pathway. BALB/c mice were randomly assigned into a blank control group, a model group, low(200 mg·kg~(-1)), medium(400 mg·kg~(-1)) and high(800 mg·kg~(-1)) dose groups of ESP, and donepezil hydrochloride group. Except the blank control group, the other groups were given 20 mg·kg~(-1) aluminum chloride by gavage and 120 mg·kg~(-1) D-galactose by intraperitoneal injection for 56 days to establish Alzheimer's disease model. Morris water maze was used to detect the learning and memory ability of mice. The level of p-tau protein in mouse hippocampus and the levels of superoxide dismutase(SOD), malondialdehyde(MDA), catalase(CAT), and total antioxidant capacity(T-AOC) in hippocampus and serum were detected. Hematoxylin-eosin staining and Nissl staining were performed for the pathological observation of whole brain in mice. TdT-mediated dUTP nick-end labeling(TUNEL) staining was employed for the observation of apoptosis in mouse cortex. Western blot was adopted to detect the protein levels of p-mTOR, p-Akt, and GSK-3β in the hippocampus. Compared with the model group, the ESP groups showcased alleviated pathological damage of the whole brain, decreased TUNEL positive cells, reduced level of p-tau protein in hippocampus, and risen SOD, CAT, and T-AOC levels and declined MDA level in hippocampus and serum. Furthermore, the ESP groups had up-regulated protein levels of p-mTOR and p-Akt while down-regulated protein level of GSK-3β in hippocampus. Therefore, ESP can alleviate the learning and memory decline and oxidative damage in mice with Alzheimer's disease induced by D-galactose combined with aluminum chloride, which may be related to Akt/mTOR/GSK-3β signaling pathway.
Aluminum Chloride/adverse effects* ; Alzheimer Disease/drug therapy* ; Animals ; Galactose/metabolism* ; Glycogen Synthase Kinase 3 beta/metabolism* ; Hippocampus/metabolism* ; Mice ; Mice, Inbred BALB C ; Plant Extracts ; Proto-Oncogene Proteins c-akt/metabolism* ; Signal Transduction ; Superoxide Dismutase/metabolism* ; TOR Serine-Threonine Kinases/metabolism* ; tau Proteins

Asthenoteratozoospermia is one of the most severe types of qualitative sperm defects. Most cases are due to mutations in genes encoding the components of sperm flagella, which have an ultrastructure similar to that of motile cilia. Coiled-coil domain containing 103 (CCDC103) is an outer dynein arm assembly factor, and pathogenic variants of CCDC103 cause primary ciliary dyskinesia (PCD). However, whether CCDC103 pathogenic variants cause severe asthenoteratozoospermia has yet to be determined. Whole-exome sequencing (WES) was performed for two individuals with nonsyndromic asthenoteratozoospermia in a consanguineous family. A homozygous CCDC103 variant segregating recessively with an infertility phenotype was identified (ENST00000035776.2, c.461A>C, p.His154Pro). CCDC103 p.His154Pro was previously reported as a high prevalence mutation causing PCD, though the reproductive phenotype of these PCD individuals is unknown. Transmission electron microscopy (TEM) of affected individuals' spermatozoa showed that the mid-piece was severely damaged with disorganized dynein arms, similar to the abnormal ultrastructure of respiratory ciliary of PCD individuals with the same mutation. Thus, our findings expand the phenotype spectrum of CCDC103 p.His154Pro as a novel pathogenic gene for nonsyndromic asthenospermia.
Asthenozoospermia/pathology* ; Dyneins/genetics* ; Homozygote ; Humans ; Male ; Microtubule-Associated Proteins ; Mutation ; Mutation, Missense ; Sperm Tail/metabolism*

This study was to investigate the changes of autophagy in pancreatic tissue cells from hyperlipidemic acute pancreatitis (HLAP) rats and the molecular mechanism of autophagy to induce inflammatory injury in pancreatic tissue cells. Male Sprague Dawley (SD) rats were intraperitoneally injected with caerulein to establish acute pancreatitis (AP) model and then given a high fat diet to further prepare HLAP model. The HLAP rats were treated with autophagy inducer rapamycin or inhibitor 3-methyladenine. Pancreatic acinar (AR42J) cells were treated with caerulein to establish HLAP cell model. The HLAP cell model were treated with rapamycin or transfected with vascular endothelial growth factor (VEGF) siRNA. The inflammatory factors in serum and cell culture supernatant were detected by ELISA method. The histopathological changes of pancreatic tissue were observed by HE staining. The changes of ultrastructure and autophagy in pancreatic tissue were observed by electron microscopy. The expression levels of Beclin-1, microtubule- associated protein light chain 3-II (LC3-II), mammalian target of rapamycin complex 1 (mTORC1), and VEGF were measured by immunohistochemistry and Western blot. The results showed that, compared with control group, the autophagy levels and inflammatory injury of pancreatic tissue cells from HLAP model rats were obviously increased, and these changes were aggravated by rapamycin treatment, but alleviated by 3-methyladenine treatment. In HLAP cell model, rapamycin aggravated the autophagy levels and inflammatory injury, whereas VEGF siRNA transfection increased mTORC1 protein expression, thus alleviating the autophagy and inflammatory injury of HLAP cell model. These results suggest that VEGF-induced autophagy plays a key role in HLAP pancreatic tissue cell injury, and interference with VEGF-mTORC1 pathway can reduce the autophagy levels and alleviate the inflammatory injury. The present study provides a new target for prevention and treatment of HLAP.
Acute Disease ; Animals ; Autophagy ; Ceruletide/adverse effects* ; Male ; Mammals/metabolism* ; Mechanistic Target of Rapamycin Complex 1 ; Microtubule-Associated Proteins/metabolism* ; Pancreatitis ; RNA, Small Interfering/genetics* ; Rats ; Rats, Sprague-Dawley ; Sirolimus/adverse effects* ; Vascular Endothelial Growth Factor A/genetics*

Objective To study the effects of TYRO protein kinase-binding protein (TYROBP) deficiency on learning behavior, glia activation and pro-inflammatory cycokines, and Tau phosphorylation of a new Alzheimer's disease (AD) mouse model carrying a <i>PSEN1i> p.G378E mutation.Methods A new AD mouse model carrying <i>PSEN1i> p.G378E mutation was built based on our previously found AD family which might be ascribed to the <i>PSEN1i> mutation, and then crossed with TYROBP deficient mice to produce the heterozygous hybrid mice (<i>PSEN1^G378E/WTi>; <i>Tyrobp^+/-i>) and the homozygous hybrid mice (<i>PSEN1^G378E/G378Ei>; <i>Tyrobp^-/-i>). Water maze test was used to detect spatial learning and memory ability of mice. After the mice were sacrificed, the hippocampus was excised for further analysis. Immunofluorescence was used to identify the cell that expresses TYROBP and the number of microglia and astrocyte. Western blot was used to detect the expression levels of Tau and phosphorylated Tau (p-Tau), and ELISA to measure the levels of pro-inflammatory cytokines. Results Our results showed that TYROBP specifically expressed in the microglia of mouse hippocampus. Absence of TYROBP in <i>PSEN1^G378Ei> mutation mouse model prevented the deterioration of learning behavior, decreased the numbers of microglia and astrocytes, and the levels of interleukin-6, interleukin-1β and tumor necrosis factor-<i>αi> in the hippocampus (all <i>Pi> < 0.05). The ratios of AT8/Tau5, PHF1/Tau5, pT181/Tau5, pT231/Tau5 and p-ERK/ERK were all higher in homozygous hybrid mice (<i>PSEN1^G378E/G378Ei>; <i>Tyrobp^-/-i> mice) compared with <i>PSEN1^G378E/G378Ei> mice (all <i>Pi> < 0.05). Conclusions TYROBP deficiency might play a protective role in the modulation of neuroinflammation of AD. However, the relationship between neuroinflammation processes involving microglia and astrocyte activation, and release of pro-inflammatory cytokines, and p-Tau pathology needs further study.
Mice ; Animals ; Alzheimer Disease/genetics* ; Neuroinflammatory Diseases ; Hippocampus/pathology* ; Mutation ; Cytokines/pharmacology* ; Disease Models, Animal ; tau Proteins/pharmacology* ; Amyloid beta-Peptides/metabolism* ; Adaptor Proteins, Signal Transducing/pharmacology*