Influenza Vaccination Mediates SARS-CoV-2 Spike Protein Peptide-Induced Inflammatory Response via Modification of Histone Acetylation.

The effectiveness of coronavirus disease 2019 (COVID-19) vaccines against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain rapidly wanes over time. Growing evidence from epidemiological studies suggests that influenza vaccination is associated with a reduction in the risk of SARS-CoV-2 infection and COVID-19 severity. However, the underlying mechanisms remain elusive. Here, we investigate the cross-reactive immune responses of influenza vaccination to SARS-CoV-2 spike protein peptides based on in vitro study. Our data indicate enhanced activation-induced-marker (AIM) expression on CD4+ T cells in influenza-vaccination (IV)-treated peripheral blood mononuclear cells (PBMCs) upon stimulation with spike-protein-peptide pools. The fractions of other immune cell subtypes, including CD8+ T cells, monocytes, NK cells, and antigen-presenting cells, were not changed between IV-treated and control PBMCs following ex vivo spike-protein-peptide stimulation. However, the classical antiviral (IFN-γ) and anti-inflammatory (IL-1RA) cytokine responses to spike-protein-peptide stimulation were still enhanced in PBMCs from both IV-immunized adult and aged mice. Decreased expression of proinflammatory IL-1ß, IL-12p40, and TNF-α is associated with inhibited levels of histone acetylation in PBMCs from IV-treated mice. Remarkably, prior immunity to SARS-CoV-2 does not result in modification of histone acetylation or hemagglutinin-protein-induced cytokine responses. This response is antibody-independent but can be mediated by manipulating the histone acetylation of PBMCs. These data experimentally support that influenza vaccination could induce modification of histone acetylation in immune cells and reveal the existence of potential cross-reactive immunity to SARS-CoV-2 antigens, which may provide insights for the adjuvant of influenza vaccine to limit COVID-19-related inflammatory responses.

Changes in the Main Physicochemical Properties and Electrochemical Fingerprints in the Production of Sea Buckthorn Juice by Pectinase Treatment.

Enzymatic hydrolysis using pectinase is critical for producing high-yield and quality sea buckthorn juice. This study determined the optimal temperature, time, and enzyme dosage combinations to guide manufacturers. A temperature of 60 °C, hydrolysis time of 3 h, and 0.3% enzyme dosage gave 64.1% juice yield-25% higher than without enzymes. Furthermore, monitoring physicochemical properties reveals enzyme impacts on composition. Higher dosages increase soluble solids up to 15% and soluble fiber content by 35% through cell wall breakdown. However, excessive amounts over 0.3% decrease yields. Pectin concentration also declines dose-dependently, falling by 91% at 0.4%, improving juice stability but needing modulation to retain viscosity. Electrochemical fingerprinting successfully differentiates process conditions, offering a rapid quality control tool. Its potential for commercial inline use during enzymatic treatment requires exploration. Overall, connecting optimized parameters to measured effects provides actionable insights for manufacturers to boost yields, determine enzyme impacts on nutrition/functionality, and introduce novel process analytical technology. Further investigations of health properties using these conditions could expand sea buckthorn juice functionality.

Comprehensive molecular findings in primary malignant melanoma of the esophagus: A multicenter study.

Primary malignant melanoma of the esophagus (PMME) is an extremely rare but highly aggressive malignancy with a poor prognosis. Due to the scarcity of driver gene alterations, there is a need for more clinical data to comprehensively depict its molecular alterations. This study reviewed 26 PMME cases from three medical centers. Hybrid capture-based targeted sequencing of 295 and 1021 genes was performed in 14 and 12 cases, respectively. We found that PMME patients had a relatively low tumor mutation burden (median, 2.88 mutations per Mb) and were simultaneously accompanied by mutations in genes such as KIT (6/26, 23%), TP53 (6/26, 23%), SF3B1 (4/26, 15%), and NRAS (3/26, 12%). KIT, NRAS, and BRAF were mutually exclusive, and SF3B1 co-occurred with KIT mutation and amplification. The most common pathways affected were the mitogen-activated protein kinases and DNA damage response (DDR) pathways. Stage IV was a risk factor for both progression-free survival (hazard ratio [HR] = 5.14, 95% confidence interval [CI] = 1.32-19.91) and overall survival (OS), HR = 4.33, 95% CI = 1.22-15.30). Treatment with immune-checkpoint inhibitors (ICIs) was an independent factor for favorable OS (HR = 0.10, 95% CI = 0.01-0.91). Overall, PMME is a complex malignancy with diverse gene alterations, especially with harboring DDR alterations for potentially response from ICIs.

Choroid plexus mast cells drive tumor-associated hydrocephalus.

Tumor-associated hydrocephalus (TAH) is a common and lethal complication of brain metastases. Although other factors beyond mechanical obstructions have been suggested, the exact mechanisms are unknown. Using single-nucleus RNA sequencing and spatial transcriptomics, we find that a distinct population of mast cells locate in the choroid plexus and dramatically increase during TAH. Genetic fate tracing and intracranial mast-cell-specific tryptase knockout showed that choroid plexus mast cells (CPMCs) disrupt cilia of choroid plexus epithelia via the tryptase-PAR2-FoxJ1 pathway and consequently increase cerebrospinal fluid production. Mast cells are also found in the human choroid plexus. Levels of tryptase in cerebrospinal fluid are closely associated with clinical severity of TAH. BMS-262084, an inhibitor of tryptase, can cross the blood-brain barrier, inhibit TAH in vivo, and alleviate mast-cell-induced damage of epithelial cilia in a human pluripotent stem-cell-derived choroid plexus organoid model. Collectively, we uncover the function of CPMCs and provide an attractive therapy for TAH.

Clinical significance of genetic profiling based on different anatomic sites in patients with mucosal melanoma who received or did not receive immune checkpoint inhibitors.

BACKGROUND: To date, data on the efficacy of targeted therapies for mucosal melanoma (MM) are limited. In this study, we analyzed genetic alterations according to the primary site of origin, which could provide clues for targeted therapy for MM. METHODS: We conducted a retrospective cohort study of 112 patients with MM. Targeted sequencing was performed to analyze genetic aberrations. Kaplan-Meier analysis was conducted with the log-rank test to compare the significance among subgroups. RESULTS: In total, 112 patients with MM were included according to the anatomic sites: 38 (33.9%) in the head and neck, 22 (19.6%) in the genitourinary tract, 21 (18.8%) in the anorectum, 19 (17.0%) in the esophagus, 10 (8.9%) in the uvea, and 2 (1.8%) in the small bowel. The most significantly mutated genes included BRAF (17%), KIT (15%), RAS (15%), TP53 (13%), NF1 (12%), SF3B1 (11%), GNA11 (7%), GNAQ (5%), and FBXW7 (4%). A large number of chromosomal structural variants was found. The anatomic sites of esophagus and small bowel were independent risk factors for progression-free survival (PFS, hazard ratio [HR] 4.78, 95% confidence interval [CI] 2.42-9.45, P < 0.0001) and overall survival (OS, HR 5.26, 95% CI 2.51-11.03, P < 0.0001). Casitas B-lineage lymphoma (CBL) mutants showed significantly poorer PFS and OS. In contrast, MM patients who received immune checkpoint inhibitors (ICIs) had a significantly more favorable OS (HR 0.39, 95% CI 0.20-0.75, P = 0.008). CONCLUSIONS: Our findings reveal the genetic features of patients with MM, mainly across six anatomic sites, offering a potential avenue for targeted therapies.

VEGF-A in serum protects against memory impairment in APP/PS1 transgenic mice by blocking neutrophil infiltration.

Activation of innate immunity in the brain is a prominent feature of Alzheimer's disease (AD). The present study investigated the regulation of innate immunity by wild-type serum injection in a transgenic AD mouse model. We found that treatment with wild-type mouse serum significantly reduced the number of neutrophils and microglial reactivity in the brains of APP/PS1 mice. Mimicking this effect, neutrophil depletion via Ly6G neutralizing antibodies resulted in improvements in AD brain functions. Serum proteomic analysis identified vascular endothelial growth factor-A (VEGF-A) and chemokine (C-X-C motif) ligand 1 (CXCL1) as factors enriched in serum samples, which are crucial for neutrophil migration and chemotaxis, leukocyte migration, and cell chemotaxis. Exogenous VEGF-A reversed amyloid ß (Aß)-induced decreases in cyclin-dependent kinase 5 (Cdk5) and increases in CXCL1 in vitro and blocked neutrophil infiltration into the AD brain. Endothelial Cdk5 overexpression conferred an inhibitory effect on CXCL1 and neutrophil infiltration, thereby restoring memory abilities in APP/PS1 mice. Our findings uncover a previously unknown link between blood-derived VEGF signaling and neutrophil infiltration and support targeting endothelial Cdk5 signaling as a potential therapeutic strategy for AD.

Validation of suitable reference genes by various algorithms for gene expression analysis in Isodon rubescens under different abiotic stresses.

Isodon rubescens (Hemsley) H. Hara (Lamiaceae) is a traditional Chinese medicine plant that has been used to treat various human diseases. Oridonin is one of the main active ingredients, and the route of its molecular biosynthesis remains to be determined. The study of gene expression patterns can provide clues toward the understanding of its biological functions. The selection of suitable reference genes for normalizing target gene expression is the first steps in any quantitative real-time PCR (RT-qPCR) gene expression study. Therefore, validation of suitable reference genes is necessary for obtaining reliable results in RT-qPCR analyses of I. rubescens. Here, 12 candidate reference genes were chosen, and their expression stability in different tissues of I. rubescens and in leaves under different abiotic stresses (NaCl, dehydration, SA, MeJA, and ABA) was evaluated using the ∆Ct, NormFinder, GeNorm, BestKeeper, and RankAggreg statistical tools. Analysis using the comprehensive tools of RankAggreg algorithm showed that GADPH, 18S and eIF were stably expressed in different tissues; UBQ, Apt, and HIS; Cycl, UBQ, and PP2A; GADPH, 18S, and eIF; eIF, UBQ, and PP2A; TUB, Cycl, and UBQ; were the best three candidate reference genes for the samples of Dehydration, NaCl, SA, MeJA, and ABA treatment, respectively. While for the concatenated sets of ND (NaCl and dehydration) and SMA (SA, MeJA, and ABA), UBQ, HIS, and TUA; UBQ, eIF and Apt were the three appropriate candidate reference genes, respectively. In addition, the expression patterns of HMGR in different tissues and under different treatments were used to confirm the reliability of the selected reference genes, indicating that the use of an inappropriate reference gene as the internal control will cause results with a large deviation. This work is the first study on the expression stability of reference genes in I. rubescens and will be particularly useful for gene functional research in this species.

Molecular Cloning and Functional Analysis of IrUGT86A1-like Gene in Medicinal Plant Isodon rubescens (Hemsl.) Hara.

The synthesis of secondary metabolites in plants often includes glycosylation modifications. Often, the final step of constructing plant secondary metabolites is completed by glycosylation transferases, which are also involved in many cell processes. In this study, a UDP-glycosyltransferase gene (UGT) was amplified from Isodon rubescens (Hemsl.) Hara with RT-PCR and named IrUGT86A1-like (GenBank: MZ913258). Here, we found that IrUGT86A1-like gene is 1450 bp in length and encodes for 479 amino acids. Bioinformatics analysis revealed that IrUGT86A1-like is a stable and hydrophilic protein, located in the cytoplasm with a transmembrane domain. Phylogenetic analysis showed that IrUGT86A1-like protein has the closest genetic relationship with the UDP-glycosyltransferase 86A1-like protein (XP_042054241.1) of Salvia splendens. RT-qPCR analysis demonstrated that the expression of IrUGT86A1-like gene varied in different tissues; leaves had the highest expression followed by flowers, stems, and roots had the lowest expression. This expression trend is similar to the distribution of oridonin content in different tissues of I. rubescens. Additionally, IrUGT86A1-like gene was found to be positively enhanced by NaCl and MeJA treatment, and in contrast was down-regulated by ABA treatment. Finally, the prokaryotic expression vector pEASY®-Blunt E1-IrUGT86A1 was successfully used to express about 53 KD of IrUGT86A1-like protein. This research builds a foundation for further investigation on the function of this gene in the synthesis and modification of secondary metabolites.

The APP intracellular domain promotes LRRK2 expression to enable feed-forward neurodegenerative mechanisms in Parkinson's disease.

Gain-of-function mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are common in familial forms of Parkinson's disease (PD), which is characterized by progressive neurodegeneration that impairs motor and cognitive function. We previously demonstrated that LRRK2-mediated phosphorylation of ß-amyloid precursor protein (APP) triggers the production and nuclear translocation of the APP intracellular domain (AICD). Here, we connected LRRK2 to AICD in a feed-forward cycle that enhanced LRRK2-mediated neurotoxicity. In cooperation with the transcription factor FOXO3a, AICD promoted LRRK2 expression, thus increasing the abundance of LRRK2 that promotes AICD activation. APP deficiency in LRRK2G2019S mice suppressed LRRK2 expression, LRRK2-mediated mitochondrial dysfunction, α-synuclein accumulation, and tyrosine hydroxylase (TH) loss in the brain, phenotypes associated with toxicity and loss of dopaminergic neurons in PD. Conversely, AICD overexpression increased LRRK2 expression and LRRK2-mediated neurotoxicity in LRRK2G2019S mice. In LRRK2G2019S mice or cultured dopaminergic neurons from LRRK2G2019S patients, treatment with itanapraced reduced LRRK2 expression and was neuroprotective. Itanapraced showed similar effects in a neurotoxin-induced PD mouse model, suggesting that inhibiting the AICD may also have therapeutic benefits in idiopathic PD. Our findings reveal a therapeutically targetable, feed-forward mechanism through which AICD promotes LRRK2-mediated neurotoxicity in PD.

An unusual sternalis with variation of the contralateral sternocleidomastoid muscle: a case report.

PURPOSE: To report a previously undocumented variant of sternalis. METHODS: An unusual muscle was observed during routine dissection. RESULTS: The sternalis muscle located in the right thoracic region originated from the superior portion of the rectus abdominis sheath and 5-6th costal cartilages, crossed the midline and attached at the sternum. The muscle fibers then ascended with the left sternocleidomastoid muscle as an additional fasciculus, of which the superior ends were finally terminated at the left mastoid process. The sternalis muscle of the thoracic region was innervated by the anterior cutaneous branches of right intercostal nerve, while the additional fasciculus ascended with the left sternocleidomastoid muscle was innervated by the branches of left accessory nerve. CONCLUSIONS: This study presents a unilateral sternalis muscle with the contralateral sternocleidomastoid variation. It will enhance the exhaustive classification of sternalis, and provide significant information to radiologists, angiologists and surgeons for better interpretation of images and safer interventions.

Mutational landscape of primary pulmonary salivary gland-type tumors through targeted next-generation sequencing.

OBJECTIVES: Primary pulmonary salivary gland-type tumors (PSGTs) mainly comprise of mucoepidermoid carcinoma (MEC) and adenoid cystic carcinoma (ACC), which are rare and molecularly poorly understood. This study aimed to profile the molecular alterations of PSGTs via targeted next-generation sequencing (NGS). MATERIAL AND METHODS: Immunohistochemistry was used to screen PSGTs in 32 patients and MAML2 and MYB rearrangements were detected using fluorescence in situ hybridization. 1021-Genepanel of targeted NGS was conducted to profile genomic mutations in all the PSGT patients. RESULTS: Among the 32 patients, 25 had MEC and 7 had ACC. MAML2 and MYB rearrangements were detected in 80.0% (20/25) of the MEC and 71.4% (5/7) of the ACC patients. Among the MEC patients, 10 (40.0%) had ≥1 mutation, and 6 of them had 11 isolated mutations with abundance >5%, namely NFE2L2, MYOD1, INPP4B, CCND2, SNTG1, HSPD1, TGFBR1, RBM10, NOTCH4, ASXL1, and PTPRD mutations. The remaining 4 patients had 9 mutations with abundance <5%, namely KMT2A, PDCD11, FLT1, BRCA2, APC, SLX4, FOXP1, FGFR1, and HRAS mutations. All the ACC patients had mutations, which were enriched in 5 pathways including the PI3K and NOTCH pathways, chromatin and cytoskeleton remodeling, and DNA damage. These results explain PSGTs harbor distinct driver features of MAML2 or MYB rearrangement, accompanied with wide mutational diversity with very low rate of somatic mutation. Several important pathways, including the NOTCH and PI3K pathways, and chromatin remodeling could be targeted to improve the survival in patients with ACC.

Platelets transport ß-amyloid from the peripheral blood into the brain by destroying the blood-brain barrier to accelerate the process of Alzheimer's disease in mouse models.

Extracellular aggregation of the ß-amyloid (Aß) peptide into toxic multimers in the brain is a prominent event occurring in the pathogenesis of Alzheimer's disease (AD), and a large amount of Aß in the blood is derived from platelets. Thus, we speculated that platelets may play an important role in the process of AD. We first investigated the changes in platelet Aß secretion with age. Then, we injected platelets from aged amyloid precursor protein APP/PS1 mice into young C57 mice and assessed their memory capacity along with their brain and peripheral blood Aß expression levels. The Aß content in mouse platelets increased with age. Exogenously aged APP/PS1 platelets changed the permeability of the blood-brain barrier in vitro, accelerating Aß deposition in the brain and increasing the Aß content in peripheral blood, leading to learning and memory deficits in the recipient mice. Subsequently, aspirin was administered to mice as an inhibitor of platelet activation, which effectively alleviated these toxic processes. Finally, we chose an in vitro blood-brain barrier model to explore the possible cytotoxicity of these platelets.

Impaired neurogenesis in the hippocampus of an adult VPS35 mutant mouse model of Parkinson's disease through interaction with APP.

Vacuolar protein sorting protein 35 (VPS35) is a core component of the retromer complex involved in regulating protein trafficking and retrieval. Recently, a missense mutation, Asp620Asn (D620N), in VPS35 (PARK17) has been identified as a pathogenic mutation for late-onset autosomal dominant Parkinson's disease (PD). Although PD is characterized by a range of motor symptoms associated with loss of dopaminergic neurons in the substantial nigra, non-motor symptoms such as impaired hippocampal neurogenesis were observed in both PD patients and animal models of PD caused by multiple PD-linked pathogenic genes such as alpha-synuclein and leucine-rich repeat kinase 2 (LRRK2). However, the role of the VPS35 D620N mutation in adult hippocampal neurogenesis remains unknown. Here, we showed that the VPS35 D620N mutation impaired hippocampal neurogenesis in adult transgenic mice expressing the VPS35 D620N gene. Specifically, we showed a reduction in the neural stem cell pool and neural proliferation and differentiation, retarded migration, and impaired neurite outgrowth in 3-month-old VPS35 D620N mutant mice. Moreover, we found that the VPS35 D620N mutant hyperphosphorylates amyloid precursor protein (APP) at Thr668and interacts with APP. Notably, by crossing the VPS35 D620N mutant mice with APP knockout (KO) mice, we showed that loss of APP function rescues VPS35 D620N-inhibited neurogenesis, neural migration, and maturation. Our study provides important evidence that APP is involved in the VPS35 D620N mutation in regulating adult neurogenesis, which sheds light on the pathogenic mechanisms in PD.

Cultivation of humanistic values in medical education through anatomy pedagogy and gratitude ceremony for body donors.

BACKGROUND: One of the most important objectives of modern medical education is to empower medical students to become humanistic clinicians. Human anatomy plays a crucial role in this mission by using cadavers to cause reflections on death, dying, illness, and the role of medical practitioners in humanistic care. The objective of this study was to introduce, describe, and evaluate the impact of a ceremony in honor of the body donors on ethical and humanistic attitudes of medical students. METHODS: We used a phenomenological research approach to explore and understand the lived experiences of the anatomy teachers as they teach anatomy in the context of humanism and ethics. A separate survey of third-year medical students was carried out to understand their perceptions of changes in themselves, respect for donors and donor families, and their relationship with patients. Data were collected in two phases: a desktop review of teaching materials followed by in-depth interviews of the main anatomy teachers followed by a self-administered, 5-item Likert scaled questionnaire given to students. RESULTS: In the present article, we describe the rituals conducted in honor of body donors at our School of Medicine. We also describe the lived experiences of anatomy teachers as they work on improving humanistic education quality through the introduction of the concept of "silent mentor" which refers to a cadaver that quietly allows medical students to learn from it. In turn, a ceremony in honor of body donors who have altruistically donated their bodies so that learning anatomy through dissection would be possible is also introduced. A survey of the impact of the ceremony in honor of body donors on medical students revealed positive responses in terms of promoting studying anatomy (3.96 Vs 3.95) as well as reflections on own death (4.44 Vs 4.35), the life of body donors (4.07 Vs 4.04), and how to humanely view future patients and their significant others (4.32 Vs 4.24) relative to those that did not attend the ceremony (5-item Likert scale). The majority of the students that attended the ceremony also indicated that it had a positive impact on their future doctor-patient relationship, thinking about the possibility of donating their body for teaching as well as about medical ethics. Most of them also think that attending the ceremony helped reduce their anxiety, fear, and disgust of seeing corpses or dissecting and 90% insisted that memorial ceremonies should continue being conducted at Zhongshan Medical School. CONCLUSION: The combination of the anatomy component of the basic medical curriculum and gratitude ceremonies as well as activities to promote body bequeathal programs might help to accomplish the goal of cultivating high-quality medical students and professionals for the future. The long-term benefits would be a medical graduate who exudes empathy, relates well with patients and their significant others, leading to a productive doctor-patient relationship.

Amyloid precursor protein intracellular domain-dependent regulation of FOXO3a inhibits adult hippocampal neurogenesis.

The amyloid precursor protein (APP) intracellular domain (AICD) is a metabolic by-product of APP produced through sequential proteolytic cleavage by α-, ß-, and γ-secretases. The interaction between AICD and Fe65 has been reported to impair adult neurogenesis in vivo. However, the exact role of AICD in mediating neural stem cell fate remains unclear. To identify the role of AICD in neuronal proliferation and differentiation, as well as to clarify the molecular mechanisms underlying the role of AICD in neurogenesis, we first generated a mouse model expressing the Rosa26-based AICD transgene. AICD overexpression did not alter the spatiotemporal expression pattern of full-length APP or accumulation of its metabolites. In addition, AICD decreased the newly generated neural progenitor cell (NPC) pool, inhibited the proliferation and differentiation efficiency of NPCs, and increased cell death both in vitro and in vivo. Given that abnormal neurogenesis is often associated with depression-like behavior in adult mice, we conducted a forced swim test and tail suspension test with AICD mice and found a depression-like behavioral phenotype in AICD transgenic mice. Moreover, AICD stimulated FOXO3a transcriptional activation, which in turn negatively regulated AICD. In addition, functional loss of FOXO3a in NPCs derived from the hippocampal dentate gyrus of adult AICD transgenic mice rescued neurogenesis defects. AICD also increased the mRNA expression of FOXO3a target genes related to neurogenesis and cell death. These results suggest that FOXO3a is the functional target of AICD in neurogenesis regulation. Our study reveals the role of AICD in mediating neural stem cell fate to maintain homeostasis during brain development via interaction with FOXO3a.

Lycopene protects neuroblastoma cells against oxidative damage via depression of ER stress.

Lycopene is a pigment derived from tomatoes and other red fruits, and has potent antioxidant and antitumor effects. However, its potential role in alleviating oxidative damage in neuronal cells is not well defined. In this study, we investigated the effects of lycopene on H2 O2 -induced damage in neuroblastoma cells, as well as the underlying mechanisms. Exposure to H2 O2 markedly decreased the viability of SH-SY5Y cells and increased LDH release, both of which were reversed by lycopene pretreatment. Lycopene also ameliorated H2 O2 -induced damage and reduced the expression of apoptotic markers, such as Bcl-2, Bax, and cleaved caspase 3. In addition, the H2 O2 -induced oxidative markers, including MDA, 8-OHdG, and protein carbonyls, were also downregulated by lycopene. Exogenous H2 O2 activated the GRP78/PERK/eIF2α signaling pathway, which was inhibited by pretreatment with lycopene. Finally, lycopene significantly ameliorated ER stress-induced activation and nuclear translocation of CHOP. Overexpression of CHOP markedly reversed the antiapoptotic effects of lycopene, indicating that it is essential for the latter's protective effects. Taken together, lycopene protects neuroblastoma cells from oxidative stress and ER stress-induced damage by inhibiting the PERK-CHOP signaling pathway, which is a potential therapeutic target in neurodegenerative diseases. PRACTICAL APPLICATION: Lycopene demonstrated antioxidative damage properties in protecting the neural system in vitro. The present study provides a novel preventive strategy against neurodegenerative diseases. Increased consumption of lycopene-based products and lycopene-rich fruits and vegetables may result in a lower risk for neurodegenerative diseases.

Lycopene alleviates oxidative stress via the PI3K/Akt/Nrf2pathway in a cell model of Alzheimer's disease.

BACKGROUND & AIMS: Oxidative stress (OS) plays an important role in neurodegenerative diseases such as Alzheimer's disease (AD). Lycopene is a pigment with potent antioxidant and anti-tumor effects. However, its potential role in central nervous system is not well-defined. The aim of this study was to investigate the effect of lycopene on the cell model of AD and determine its underlying mechanisms. METHODS: M146L cell is a double-transfected (human APP gene and presenlin-1 gene) Chinese hamster ovary (CHO) cell line that overexpresses ß -amyloid (Aß) and is an ideal cell model for AD. We treated cells with lycopene, and observed the effect of lycopene on M146L cells. RESULTS: Oxidative stress and apoptosis in M146L cells were significantly higher than those in CHO cells, suggesting that Aß induced OS and apoptosis. Lycopene alleviated OS and apoptosis, activated the PI3K/Akt/Nrf2 signaling pathway, upregulated antioxidant and antiapoptotic proteins and downregulated proapoptotic proteins. Additionally, lycopene inhibited ß -secretase (BACE) activity in M146L cells. These results suggest that lycopene inhibits BACE activity and protects M146L cells from oxidative stress and apoptosis by activating the PI3K/Akt/Nrf2 pathway. CONCLUSION: Lycopene possibly prevents Aß-induced damage by activating the PI3K/Akt/Nrf2 signaling pathway and reducing the expression of BACE in M146L cells.

Cyclovirobuxine D inhibits cell proliferation and migration and induces apoptosis in human glioblastoma multiforme and low­grade glioma.

Gliomas are the most common neoplasm of the human central nervous system. Glioblastoma multiforme (GBM) is one of the most serious types of gliomas. Although considerable progress has been made in the development of cancer therapeutic agents, several antineoplastic drugs fail to penetrate the blood­brain barrier (BBB), resulting in a low survival rate of glioma patients. Recent studies have revealed that the traditional Chinese medicine Buxus microphylla contains the main active component Cyclovirobuxine D (CVB­D), which can cross the BBB with a novel delivery system. However, it remains unclear whether CVB­D exerts anticancer effects against GBM and low­grade glioma (LGG). The aim of the present study was to explore the feasibility of CVB­D as a new effective agent in the treatment of GBM and LGG. The ability of CVB­D to inhibit GBM and LGG cell proliferation was detected by CCK8 assay. Flow cytometry was used to detect cell cycle progression and apoptosis induction by Annexin V­FITC/PI assay. The expression levels of the apoptosis­associated proteins, namely cleaved caspase­3 and Bax/Bcl­2, were detected by western blot analysis. The mitochondrial membrane potential (ΔΨm) was detected by Rh123 dyed fluorescence micrograph. Hoechst staining was used to observe the morphological characteristics of the apoptotic cells. The scratch test was used to evaluate the migration of GBM and LGG cells. The results indicated that CVB­D reduced cell viability of T98G and Hs683 cells. Flow cytometry demonstrated that CVB­D­treated cells were arrested at the S phase of their cell cycle. The expression levels of the apoptosis­associated proteins were increased in CVB­D­treated cells. Rh123 and Hoechst staining indicated morphological changes and mitochondrial membrane potential changes of the cells undergoing apoptosis. The data confirmed that CVB­D inhibited cell proliferation by arresting the cell cycle of GBM and LLG cells and that it promoted the induction of cell apoptosis by altering the mitochondrial membrane potential. The findings of the present study indicate the potential value of CVB­D in the treatment of glioma.

Studies on APP metabolism related to age-associated mitochondrial dysfunction in APP/PS1 transgenic mice.

The aging brain with mitochondrial dysfunction and a reduced adenosine 5'-triphosphate (ATP) has been implicated in the onset and progression of ß-Amyloid (Aß)-induced neuronal toxicity in AD. To unravel the function of ATP and the underlying mechanisms on AD development, APP/PS1 double transgenic mice and wild-type (WT) C57 mice at 6 and 10 months of age were studied. We demonstrated a decreased ATP release in the hippocampus and platelet of APP/PS1 mice, comparing to C57 mice at a relatively early age. Levels of Aß were raised in both hippocampus and platelet of APP/PS1 mice, accompanied by a decrease of α-secretase activity and an increase of ß-secretase activity. Moreover, our results presented an age-dependent rise in mitochondrial vulnerability to oxidation in APP/PS1 mice. In addition, we found decreased pSer473-Akt levels, increased GSK3ß activity by inhibiting phosphorylation at Ser9 in aged APP/PS1 mice and these dysfunctions probably due to down-regulation of Bcl-2 and up-regulation of cleaved caspase-3. Therefore, we demonstrate that PI3K/Akt/GSK3ß signaling pathway could be involved in Aß-associated mitochondrial dysfunction of APP/PS1 mice and APP abnormal metabolism in platelet might provide potential biomarkers for early diagnosis of AD.

Abnormal platelet amyloid-ß precursor protein metabolism in SAMP8 mice: Evidence for peripheral marker in Alzheimer's disease.

Senescence-accelerated mouse strains have proved to be an accelerated-aging model, which mimics numerous features with Alzheimer's disease (AD). Three, six, and nine-month senescence-accelerated resistant 1 and senescence-accelerated prone 8 (SAMP8) mice were used in the current study, to unravel potential mechanisms for dementia and explore new diagnostic approaches for AD. The amyloid-ß (Aß40) and Aß42 levels were elevated in hippocampi and platelets from SAMP8, along with a reduced α-secretase expression and an enhanced ß-secretase expression extent with age, compared to control mice. Furthermore, hippocampal Aß40 and Aß42 of SAMP8 were positively correlated with platelet of these mice with aging progression. In addition, ß-γ-secretase-modulated proteolytic proceeding of amyloid precursor protein in platelet might work through the PI3K/Akt/GSK3ß pathway. These results indicate that platelet could be a potential early marker in the periphery to study the age-correlative aggregation of the amyloid-ß peptide in patients with AD, while still requiring the considerable study.