Inhibition of autophagosome-lysosome fusion contributes to TDCIPP-induced Aß1-42 production in N2a-APPswe cells.

Alzheimer's disease is the most common form of dementia and is characterized by cognitive impairment. The disruption of autophagosome-lysosome function has been linked to the pathogenesis of Alzheimer's disease. Tris (1,3-dichloro-2-propyl) phosphate (TDCIPP) is a widely used organophosphorus flame retardant that has the potential to cause neuronal damage. We found that TDCIPP significantly increased the expression of ß-site amyloid precursor protein (APP)-cleaving enzyme 1 (BACE1), presenilin-1 (PS1) and Aß42. Proteomic studies with TMT labeling revealed changes in the profiles of N2a-APPswe cells after exposure to TDCIPP. Proteomic and bioinformatics analyses revealed that lysosomal proteins were dysregulated in N2a-APPswe cells after treatment with TDCIPP. The LC3, P62, CTSD, and LAMP1 levels were increased after TDCIPP exposure, and dysregulated protein expression was validated by Western blotting. The exposure to TDCIPP led to the accumulation of autophagosomes, and this phenomenon was enhanced in the presence of chloroquine (CQ). Our results revealed for the first time that TDCIPP could be a potential environmental risk factor for AD development. The inhibition of autophagosome-lysosome fusion may have a significant impact on the generation of Aß1-42 in response to TDCIPP.

A quantitative proteomic study reveals oxidative stress and synapse-related proteins contributed to TDCIPP exposure induced neurotoxicity.

Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) has been consistently identified in various environmental media and biological specimens. Current understanding of the in vivo toxicities of TDCIPP is limited, especially for potential for neurotoxic and cognitive impairment effects. To better evaluate the potential adverse effect of the chemical on learning and memory, Sprague Dawley (SD) rats were administered TDCIPP via gavage at doses of 40, 120, and 360 mg/kg/day for a period of 90 days. Quantitative proteomic analysis, immunohistochemistry, and Western blotting were employed to assess alterations in proteins following exposure to TDCIPP. An open field test and the Morris Water Maze were used to assess anxiety and spatial learning memory capacity. Administration of TDCIPP induced anxiety and cognitive impairments in rats. Additionally, a noteworthy decrease in the number of neurons was observed in the hippocampal CA3 and dentate gyrus (DG) regions. Proteomic and bioinformatic analyses revealed dysregulation of numerous hippocampal proteins, particularly those associated with synapses (PKN1) or oxidative stress (GSTM4, NQO1, and BMAL1), which was further confirmed by Western blot analysis. In sum, the cognitive impairment of rats caused by TDCIPP exposure was associated with dysregulation of synaptic and oxidative stress-related proteins.

Exploring the mechanism of probiotics in enhancing the utilization of chemical components (or polyphenols) of grape seed extract.

Fecal samples from 20 healthy adults were collected for in vitro fermentation experiments to investigate the effects of combined probiotics on the utilization of grape seed extract in humans. After fermenting for 24 h, short-chain fatty acids, metabolites, and gut microbiota composition were analyzed. Short-chain fatty acids in the grape seed extract probiotics group were significantly higher than those in the grape seed extract group. Probiotics significantly enhanced the conversion and utilization of catechins and epicatechins in grape seed extract group and increased the production of 3-hydroxyphenylacetic acid. The 16S rRNA sequencing results revealed that compound probiotics significantly increased the relative abundance of Lacticaseibacillus, HT002, Bifidobacterium, and Lactobacillus and reduced that of Escherichia-Shigella. Our findings showed considerable individual variability in the metabolic utilization of grape seed extract in humans. The consumption of probiotics appears to significantly enhance the utilization.

Urinary nicotine metabolites are associated with cognitive impairment among the elderly in southern China.

INTRODUCTION: This study comprehensively assessed the association between eight metabolites of urinary nicotine and cognitive impairment. METHODS: This cross-sectional study was based on the data of Shenzhen Aging Related Disorder Cohort (SADC), including 51 elderly community data variables such as demographic characteristics, neuropsychological assessment and environmental factors, from July 2017 to November 2018. Participant's cognitive function was assessed by Mini-Mental State Examination (MMSE) scale and urinary nicotine metabolite [including cotinine N-ß-D-glucuronide (CotGluc), rac 4-hydroxy-4-(3-pyridyl) butanoic acid dicyclohexylamine salt (HyPyBut), trans-3'-hydroxy cotinine O-ß-D-glucuronide (OHCotGluc), and cotinine (Cot), etc.] concentrations were measured by high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). Generalized linear models and restricted cubic spline models were used to explore the relationships between the urinary levels of nicotine metabolite and cognitive function. RESULTS: A total of 296 individuals aged >60 years were included. Individuals in the third quartile of CotGluc had a 0.786 point (95% CI: -1.244 - -0.329) decrease or in the highest quartile of OHCotGluc had a 0.804 point (95% CI: -1.330 - -0.278) decreased in attention and calculation compared to those in the lowest quartile (all p for trend <0.05). Compared with those in the lowest quartile, individuals in the highest quartile of CotGluc, HyPyBut, OHCotGluc and Cot, respectively, corresponded to a 1.043 point (95% CI: -2.269-0.182), 1.101 points (95% CI: -2.391-0.188), 2.318 points (95% CI: -3.615 - -1.020), and 1.460 points (95% CI: -2.726 - -0.194) decreased in MMSE total score (all p for trend <0.05). A non-linear dose-response relationship between urinary levels of CotGluc, HyPyBut, OHCotGluc or Cot and cognitive function (all overall p<0.05, non-linear p<0.05). Subgroup analysis showed that urinary levels of CotGluc, OHCotGluc or Cot were significantly negatively associated with cognitive function (all p for trend <0.05) among females and non-smokers. CONCLUSIONS: The findings highlight the public health implications of environmental tobacco smoke exposure, and effective interventions need to be performed for vulnerable populations.

Urinary essential and toxic metal mixtures, and type 2 diabetes mellitus: Telomere shortening as an intermediary factor?

The joint effect of metal mixtures on telomere function and type 2 diabetes mellitus (T2DM) is unclear. This large-scale cross-sectional study sought to assess the role of telomere length (TL) in the relationship between urinary essential and toxic metal mixtures, and T2DM in 7410 Chinese adults ≥ 60 years of age. Essential (Cr, Cu, Zn, Se) and non-essential metals (V, Al, Sb, Sn, Cd, Pb) in urine samples were quantified, while leukocyte TL was measured from blood samples. Restricted cubic splines regression showed nonlinear relationships between single metal and T2DM, and between TL and T2DM. Bayesian kernel machine regression and quantile-based g-computation showed that the overall status of urinary metals was positively associated with risk of developing T2DM, which was mainly explained by exposure to Pb, Cd, and Sb, excessive Se intake, and high excretion of Zn. Mediation analyses showed that shortened TL mediated 27.9% of the overall positive effect of metal exposure on T2DM, and this mediation was mainly explained by toxic metal exposure and excessive Se intake. Tobacco smoke exposure, extensive cooking at home, and black tea consumption were found to be important contributors of toxic metal exposures. Further studies are needed to explore the recommended Zn dosage for T2DM patients at different stages, which may ameliorate pancreatic senescence and glycemic progression.

Bicyclol attenuates high fat diet-induced non-alcoholic fatty liver disease/non-alcoholic steatohepatitis through modulating multiple pathways in mice.

Introduction: The pathological progression of non-alcoholic fatty liver disease (NAFLD) is driven by multiple factors, and non-alcoholic steatohepatitis (NASH) represents its progressive form. In our previous studies, we found that bicyclol had beneficial effects on NAFLD/ NASH. Here we aim to investigate the underlying molecular mechanisms of the bicyclol effect on NAFLD/NASH induced by high-fat diet (HFD) feeding. Methods: A mice model of NAFLD/NASH induced by HFD-feeding for 8 weeks was used. As a pretreatment, bicyclol (200 mg/kg) was given to mice by oral gavage twice daily. Hematoxylin and eosin (H&E) stains were processed to evaluate hepatic steatosis, and hepatic fibrous hyperplasia was assessed by Masson staining. Biochemistry analyses were used to measure serum aminotransferase, serum lipids, and lipids in liver tissues. Proteomics and bioinformatics analyses were performed to identify the signaling pathways and target proteins. Data are available via Proteome X change with identifier PXD040233. The real-time RT-PCR and Western blot analyses were performed to verify the proteomics data. Results: Bicyclol had a markedly protective effect against NAFLD/NASH by suppressing the increase of serum aminotransferase, hepatic lipid accumulation and alleviating histopathological changes in liver tissues. Proteomics analyses showed that bicyclol remarkably restored major pathways related to immunological responses and metabolic processes altered by HFD feeding. Consistent with our previous results, bicyclol significantly inhibited inflammation and oxidative stress pathway related indexes (SAA1, GSTM1 and GSTA1). Furthermore, the beneficial effects of bicyclol were closely associated with the signaling pathways of bile acid metabolism (NPC1, SLCOLA4 and UGT1A1), cytochrome P450-mediated metabolism (CYP2C54, CYP3A11 and CYP3A25), biological processes such as metal ion metabolism (Ceruloplasmin and Metallothionein-1), angiogenesis (ALDH1A1) and immunological responses (IFI204 and IFIT3). Discussion: These findings suggested that bicyclol is a potential preventive agent for NAFLD/NASH by targeting multiple mechanisms in future clinical investigations.

An alternative way of SARS-COV-2 to induce cell stress and elevated DNA damage risk in cardiomyocytes without direct infection.

BACKGROUND: The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) in 2020 has led to millions of deaths worldwide. Case reports suggested that infection of SARS-CoV-2 is potentially associated with occurrences of cardiovascular pathology. However, the mode of action and mechanisms of SARS-CoV-2 influencing cardiomyocytes still remain largely unclear. AIMS: To explore the mechanisms underlying cardiomyocytes damage induced by SARS-CoV-2 infection. MATERIALS & METHODS: the serum markers of cardiovascular injury were analyzed by ELISA. The isolated SARS-CoV-2 virus were co-cultured with human cardiomyocytes (AC16) and immunofluorescence assay was used evaluate the invasion of virus. Moreover, serum obtained from acute stage of SARS-CoV-2 infected patients and healthy controls were used to incubate with AC16 cells, then indicators associated with cell stress and DNA damage were analyzed by Western-blot. RESULTS: we found that high-sensitivity troponin T (hsTnT), an indicator of cardiovascular disease, was higher in the acute stage of COVID-19. Additionally, in vitro coculture of SARS-CoV-2 and AC16 cells showed almost no infectious ability of SARS-CoV-2 to directly infect AC16 cells. Results of serum treatment suggested that serum from infected subjects induced cell stress (upregulation of p53 and HSP70) and elevation of DNA damage risk (increased γH2Ax and H3K79me2) in AC16. DISCUSSION: our observations indicated a hard way for SARS-CoV-2 to infect cardiomyocytes directly. However, infection-induced immune storm in serum could bring stress and elevated DNA damage risks to cardiovascular system. CONCLUSION: These findings indicated the possibilities of SARS-CoV-2 inducing stress and elevating DNA damage risk to cardiomyocytes without direct infection.

A quantitative proteomic analysis reveals the potential roles of PRDX3 in neurite outgrowth in N2a-APPswe cells.

Alzheimer's disease (AD) is characterized by amyloid plaques and neurofibrillary tangles accompanied by progressive neurite loss. Mitochondria play pivotal roles in AD development. PRDX3 is a mitochondrial peroxide reductase critical for H2O2 scavenging and signal transduction. In this study, we found that PRDX3 knockdown (KD) in the N2a-APPswe cell line promoted retinoic acid (RA)-induced neurite outgrowth but did not reduce the viability of cells damaged by tert-butyl hydroperoxide (TBHP). We found that knocking down PRDX3 expression induced dysregulation of more than one hundred proteins, as determined by tandem mass tag (TMT)-labeled proteomics. A Gene Ontology (GO) analysis revealed that the dysregulated proteins were enriched in protein localization to the plasma membrane, the lipid catabolic process, and intermediate filament cytoskeleton organization. A STRING analysis showed close protein-protein interactions among dysregulated proteins. The expression of Annexin A1 (ANXA1), serine (Ser)-/threonine (Thr)-protein phosphatase 2A catalytic subunit alpha isoform (PP2A) and glutathione S-transferase Mu 2 (GSTM2) was significantly upregulated in PRDX3-KD N2a-APPswe cell lines, as verified by western blotting. Our study revealed, for the first time, that PRDX3 may play important roles in neurite outgrowth and AD development.

SOD1 is a Possible Predictor of COVID-19 Progression as Revealed by Plasma Proteomics.

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a worldwide health emergency. Patients infected with SARS-CoV-2 present with diverse symptoms related to the severity of the disease. Determining the proteomic changes associated with these diverse symptoms and in different stages of infection is beneficial for clinical diagnosis and management. Here, we performed a tandem mass tag-labeling proteomic study on the plasma of healthy controls and COVID-19 patients, including those with asymptomatic infection (NS), mild syndrome, and severe syndrome in the early phase and the later phase. Although the number of patients included in each group is low, our comparative proteomic analysis revealed that complement and coagulation cascades, cholesterol metabolism, and glycolysis-related proteins were affected after infection with SARS-CoV-2. Compared to healthy controls, ELISA analysis confirmed that SOD1, PRDX2, and LDHA levels were increased in the patients with severe symptoms. Both gene set enrichment analysis and receiver operator characteristic analysis indicated that SOD1 could be a pivotal indicator for the severity of COVID-19. Our results indicated that plasma proteome changes differed based on the symptoms and disease stages and SOD1 could be a predictor protein for indicating COVID-19 progression. These results may also provide a new understanding for COVID-19 diagnosis and treatment.

Flavanol-rich lychee fruit extract substantially reduces progressive cognitive and molecular deficits in a triple-transgenic animal model of Alzheimer disease.

Effective treatment to prevent or arrest the advance of Alzheimer disease (AD) has yet to be discovered. We investigated whether OligonolR, an FDA-approved flavanol-rich extract prepared from lychee fruit and green tea, exerted beneficial effects relevant to AD in a triple transgenic male mouse model of AD (3×Tg-AD). At 9 months of age, untreated 3×Tg-AD mice vs. wild-type (WT) controls displayed cognitive deficits in behavioral assays and, at 12 months, elevated levels of hippocampal amyloid beta-protein (Aß), amyloid precursor protein (APP), tau phosphorylation, and pro-inflammatory cytokines. 3×Tg-AD mice given Oligonol showed fewer cognitive deficits and attenuated pathological indices at 12 months. Oligonol treatment of 3×Tg-AD mice modulated expression of some critical brain proteins that involve multiple pathways relevant to mitochondrial dysfunction, proteasomal failure, endoplasmic reticulum (ER) stress and synaptic impairment. Together, these results demonstrate that continuous Oligonol treatment attenuates AD-like pathology and cognitive impairment of 3×Tg-AD mice and set the stage for clinical trials of this flavanol-rich plant extract in patients with early AD.

Memantine Improves Cognitive Function and Alters Hippocampal and Cortical Proteome in Triple Transgenic Mouse Model of Alzheimer's Disease.

Memantine is a non-competitive N-methyl-D-aspartate receptor (NMDAR) antagonist clinically approved for moderate-to-severe Alzheimer's disease (AD) to improve cognitive functions. There is no report about the proteomic alterations induced by memantine in AD mouse model yet. In this study, we investigated the protein profiles in the hippocampus and the cerebral cortex of AD-related transgenic mouse model (3×Tg-AD) treated with memantine. Mice (8-month) were treated with memantine (5 mg/kg/bid) for 4 months followed by behavioral and molecular evaluation. Using step-down passive avoidance (SDA) test, novel object recognition (NOR) test and Morris water maze (MWM) test, it was observed that memantine significantly improved learning and memory retention in 3xTg-AD mice. By using quantitative proteomic analysis, 3301 and 3140 proteins in the hippocampus and the cerebral cortex respectively were identified to be associated with AD abnormalities. In the hippocampus, memantine significantly altered the expression levels of 233 proteins, among which PCNT, ATAXIN2, TNIK, and NOL3 were up-regulated, and FLNA, MARK 2 and BRAF were down-regulated. In the cerebral cortex, memantine significantly altered the expression levels of 342 proteins, among which PCNT, PMPCB, CRK, and MBP were up-regulated, and DNM2, BRAF, TAGLN 2 and FRY1 were down-regulated. Further analysis with bioinformatics showed that memantine modulated biological pathways associated with cytoskeleton and ErbB signaling in the hippocampus, and modulated biological pathways associated with axon guidance, ribosome, cytoskeleton, calcium and MAPK signaling in the cerebral cortex. Our data indicate that memantine induces higher levels of proteomic alterations in the cerebral cortex than in the hippocampus, suggesting memantine affects various brain regions in different manners. Our study provides a novel view on the complexity of protein responses induced by memantine in the brain of AD.

Long-term iron exposure causes widespread molecular alterations associated with memory impairment in mice.

Limited literature available indicates the neurotoxic effects of excessive iron, however, a deep understanding of iron neurotoxicity needs to be developed. In this study, we evaluated the toxic effects of excessive iron on learning and cognitive function in long-term iron exposure (oral, 10 mg/L, 6 months) of mice by behavioral tests including novel object recognition test, step-down passive avoidance test and Morris water maze test, and further analyzed differential expression of hippocampal proteins. The behavioral tests consistently showed that iron treatment caused cognitive defects of the mice. Proteomic analysis revealed 66 differentially expressed hippocampal proteins (30 increased and 36 decreased) in iron-treated mice as compared with the control ones. Bioinformatics analysis showed that the dysregulated proteins mainly included: synapse-associated proteins (i.e. synaptosomal-associated protein 25 (SNAP25), complexin-1 (CPLX1), vesicle-associated membrane protein 2 (VAMP2), neurochondrin (NCDN)); mitochondria-related proteins (i.e. ADP/ATP translocase 1 (SLC25A4), 14-3-3 protein zeta/delta (YWHAZ)); cytoskeleton proteins (i.e. neurofilament light polypeptide (NEFL), tubulin beta-2B chain (TUBB2B), tubulin alpha-4A chain (TUBA4A)). The findings suggest that the dysregulations of synaptic, mitochondrial, and cytoskeletal proteins may be involved in iron-triggered memory impairment. This study provides new insights into the molecular mechanisms of iron neurotoxicity.

Low-dose oral copper treatment changes the hippocampal phosphoproteomic profile and perturbs mitochondrial function in a mouse model of Alzheimer's disease.

Excessive copper can cause neurotoxicity and contribute to the development of some neurological diseases; however, copper neurotoxicity and the potential mechanisms remain poorly understood. We used proteomics and phosphoproteomics to quantify protein changes in the hippocampus of wild-type and 3xTg-AD mice, both of which were treated at 6 months of age with 2 months of drinking water with or without added copper chloride (0.13 ppm concentration). A total of 3960 unique phosphopeptides (5290 phosphorylation sites) from 1406 phosphoproteins was identified. Differentially expressed phosphoproteins involved neuronal and synaptic function, transcriptional regulation, energy metabolism and mitochondrial function. In addition, low-dose copper treatment of wild-type mice decreased hippocampal mitochondrial copy number, mitochondrial biogenesis and disrupted mitochondrial dynamics; these changes were associated with increased hydrogen peroxide production (H2O2), reduced cytochrome oxidase activity and decreased ATP content. In 3xTg-AD mice, identical low-dose oral copper treatment increased axonal degeneration, which was associated with altered phosphorylation of Camk2α at T286 and phosphorylation of mitogen-activated protein kinase (ERK1/2), which involved long-term potentiation (LTP) signaling. Mitochondrial dysfunction was mainly related to changes in phosphorylation levels of glycogen synthase kinase-3 beta (GSK3ß) and serine/threonine-protein phosphatase 2B catalytic subunit alpha isoform (Ppp3ca), which involved mitochondrial biogenesis signaling. In sum, low-dose oral copper treatment changes the phosphorylation of key hippocampal proteins involved in mitochondrial, synaptic and axonal integrity. These data showing that excess of copper speeds some early events of AD changes observed suggest that excess circulating copper has the potential to perturb brain function of wild-type mice and exacerbate neurodegenerative changes in a mouse model of AD.

Dysregulation of Myosin Complex and Striated Muscle Contraction Pathway in the Brains of ALS-SOD1 Model Mice.

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal disease characterized by cortical and spinal motor neuron degeneration, some inherited cases of which are caused by mutations in the gene coding for copper-zinc superoxide dismutase-1 (SOD1). The SOD1G93A mutant model mouse, which expresses large amounts of mutant SOD1, develops adult-onset neurodegeneration of spinal motor neurons and progressive motor deficits leading to paralysis. We used the Tandem Mass Tag technique to investigate the proteome profile of hippocampus, cerebral cortex, and medulla oblongata of the SOD1G93A mutant model mice as compared with that of wild-type (WT) mice. Fifteen proteins were significantly increased or decreased (i.e., changed) in all three tissues. Gene ontology analysis revealed that the changed proteins were mainly enriched in negative regulation of reactive oxygen species, myosin complex and copper ion binding. In the Striated Muscle Contraction Pathway, most of the identified proteins were decreased in the SOD1G93A mice compared with the WT mice. Myosin-1 (MYH1), fructose-2,6-bisphosphatase TIGAR (TIGAR), and sarcoplasmic/endoplasmic reticulum calcium ATPase 1 (ATP2A1) were significantly reduced in mutant vs WT mice, as confirmed by Western blot analysis. Since myosins and tropomyosins are specific for synapse function and drive actin dynamics in the maturation of dendritic spines, changes in these proteins may contribute to perturbations of brain neuronal circuitry in addition to spinal motor neuron disease.

Hippocampal Proteomic Alteration in Triple Transgenic Mouse Model of Alzheimer's Disease and Implication of PINK 1 Regulation in Donepezil Treatment.

Donepezil is a clinically approved acetylcholinesterase inhibitor (AChEI) for cognitive improvement in Alzheimer's disease (AD). Donepezil has been used as a first-line agent for the symptomatic treatment of AD, but its ability to modify disease pathology and underlying mechanisms is not clear. We investigated the protective effects and underlying mechanisms of donepezil in AD-related triple transgenic (APPSwe/PSEN1M146V/MAPTP301L) mouse model (3×Tg-AD). Mice (8-month old) were treated with donepezil (1.3 mg/kg) for 4 months and evaluated by behavioral tests for assessment of cognitive functions, and the hippocampal tissues were examined by protein analysis and quantitative proteomics. Behavioral tests showed that donepezil significantly improved the cognitive capabilities of 3×Tg-AD mice. The levels of soluble and insoluble amyloid beta proteins (Aß1-40 and Aß1-42) and senile plaques were reduced in the hippocampus. Golgi staining of the hippocampus showed that donepezil prevented dendritic spine loss in hippocampal neurons of 3×Tg-AD mice. Proteomic studies of the hippocampal tissues identified 3131 proteins with altered expression related to AD pathology, of which 262 could be significantly reversed with donepezil treatment. Bioinformatics with functional analysis and protein-protein interaction (PPI) network mapping showed that donepezil significantly elevated the protein levels of PINK 1, NFASC, MYLK2, and NRAS in the hippocampus, and modulated the biological pathways of axon guidance, mitophagy, mTOR, and MAPK signaling. The substantial upregulation of PINK 1 with donepezil was further verified by Western blotting. Donepezil exhibited neuroprotective effects via multiple mechanisms. In particular, PINK 1 is related to mitophagy and cellular protection from mitochondrial dysfunction, which might play important roles in AD pathogenesis and represent a potential therapeutic target.

Proteomic analysis reveals the potential neuroprotective effects of tetramethylpyrazine dimer in neuro2a/APPswe cells.

Alzheimer's disease (AD) is a common neurodegenerative disease characterized by pathological processes, including abnormal amyloid deposits and filament tangles, oxidative stress, neuroinflammation, and neurotrophic insufficiency, leading to chronic and prolonged neuronal loss and cognitive deficits. Tetramethylpyrazine (TMP) is one of the main active components of Ligusticum wallichii, a traditional Chinese medicine widely used for brain related disease. Here, we synthesized the TMP derivative tetramethylpyrazine dimer (DTMP), and evaluated the potential mechanisms underlying its potential neuroprotective effects using the murine neuron-like cells (N2a) transfected with the human "Swedish" mutant amyloid precursor protein (N2aAPP). ELISA results indicated that DTMP reduced the levels of Aß1-40 and Aß1-42 in N2aAPP. Then through proteomic analysis we identified a total of 208 differentially expressed proteins in N2aAPP cells compared to the wild-type N2a cells (N2aWT), including 144 increased and 64 decreased proteins. 449 differentially expressed proteins were revealed in N2aAPP cells on DTMP treatment with 69 increased and 380 decreased proteins. Bioinformatic analysis suggested that these proteins are enriched in mitochondrial function, the electronic transmission chain, ATP binding, oxidative phosphorylation, GTPase function, the transcriptional translation process, amino acid metabolism, nucleotide binding and others. Given the vital role of mitochondria in the pathogenesis of AD, we selected the electron transport chain pathway-related molecules to further validate these findings. Western-blot analysis demonstrated that DTMP significantly increased the levels of complex I (NDUAA), complex II (SDHB), complex III (UCRI), complex IV (COX5A) and complex V (ATP5A) in N2aAPP cells. The modulation of dysregulated proteins implicated in AD pathogenesis implies the pharmacological mechanisms of DTMP and its potential as a novel therapeutic choice in AD.

Isolation and characterization of cyclic lipopeptides with broad-spectrum antimicrobial activity from Bacillus siamensis JFL15.

In this research, the antimicrobial substance anti-JFL15 was partially purified using a simple two-step extraction process from the cell-free supernatants of Bacillus siamensis JFL15. Anti-JFL15 exhibited a strong antibacterial activity against various multidrug-resistant aquatic bacterial pathogens, including Escherichia coli, Edwardsiella tarda, Pseudomonas aeruginosa, Aeromonas hydrophila, and Vibrio. Liquid chromatography-mass spectrometry revealed that anti-JFL15 contained eight cyclic lipopeptides belonging to two families: bacillomycin F (m/z 1056.56-1084.59) and surfactin (m/z 1007.65-1049.70) analogs. PCR analysis showed the presence of genes (i.e., sfp gene, surfactin synthetase D, fengycin synthetase B, iturin synthetase A, iturin synthetase C and bacillomycin synthetase D) involved in the biosynthesis of cyclic lipopeptides. This study is the first to identify cyclic lipopeptides from B. siamensis and use them to suppress the growth of various multidrug-resistant aquatic bacterial pathogens. Results indicated that B. siamensis JFL15 is a promising biocontrol agent for the effective and environmentally friendly control of various multidrug-resistant aquatic bacterial pathogens.

Genomics-guided discovery and structure identification of cyclic lipopeptides from the Bacillus siamensis JFL15.

In this research, a strain with broad-spectrum antimicrobial activities was isolated from the gastrointestinal tract of hairtail (Trichiurus haumela) and identified as Bacillus siamensis JFL15 through morphological, 16S rRNA, and average nucleotide identity analyses. The genome of B. siamensis JFL15 was sequenced, and three gene clusters involved in the biosynthesis of surfactin (srf), bacillibactin (dhb), and fengycin (fen) were predicted through antiSMASH analysis. The combined genomics-metabolics profiling of the strain revealed 20 active compounds, which belong to four main types of cyclic lipopeptides produced by Bacillus species: bacillibactin, iturin, fengycin, and surfactin. Among these lipopeptides, two high-purity antifungal components, namely, components b and c, were successfully identified as iturin A and bacillomycin F. The minimum inhibitory concentrations (MICs) of iturin A for Magnapothe grisea, Rhizoctorzia solani, and Colletotrichum gloeosporioides were 125.00, 62.50, and 125.00 µg/ml, respectively, whereas the MICs of bacillomycin F for these three organisms were 62.50, 31.25, and 62.50 µg/ml, respectively. The mechanism of bacillomycin F and iturin A against M. grisea was also investigated. Scanning electron microscopy (SEM) indicated that the surface of the hypha treated with iturin A or bacillomycin F became sunk, lumpy, and wrinkled. The diversity of the identified and predicted compounds from B. siamensis JFL15 suggested that this strain might be a promising biocontrol agent for an effective and environmentally friendly control of pathogenic microorganisms. To the best of our knowledge, this study is the first to describe cyclic lipopeptides purified and identified from B. siamensis.

Quantitative protein profiling and pathway analysis of spinal arteriovenous malformations.

Spinal arteriovenous malformations (sAVM) are rare and heterogeneous group of blood vessel disorders that affect spinal cord function directly or indirectly; however, the pathogenesis of sAVM is still unclear. In this study, we compared four sAVM specimens obtained during surgery and donated control samples in a Tandem Mass Tag (TMT)-labeled proteomic analysis. We identified 3101 proteins, 654 of which were differentially expressed in sAVM samples compared with the controls. Of these, 96 proteins were upregulated and 358 proteins were downregulated. Gene ontology (GO) analysis revealed that extracellular matrix organization in the biological process category and integrin-binding proteins in the molecular function category were the most enriched items. Two significant differentially expressed proteins (MYLK and MMP9) were verified by Western blot analysis. The pathway analysis indicated that the differentially expressed proteins in the pathways of angiogenesis, focal adhesion and cytoplasmic ribosome contributed to sAVM. The changes in protein profiles identified in this proteomic study provide an improved understanding of the pathogenesis of sAVM. The proteomics data are available via ProteomeXchange with identifier PXD007982.

TRPC1 Deletion Causes Striatal Neuronal Cell Apoptosis and Proteomic Alterations in Mice.

Transient receptor potential channel 1 (TRPC1) is widely expressed throughout the nervous system, while its biological role remains unclear. In this study, we showed that TRPC1 deletion caused striatal neuronal loss and significantly increased TUNEL-positive and 8-hydroxy-2'-deoxyguanosine (8-OHdG) staining in the striatum. Proteomic analysis by two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) coupled with mass spectrometry (MS) revealed a total of 51 differentially expressed proteins (26 increased and 25 decreased) in the stratum of TRPC1 knockout (TRPC1-/-) mice compared to that of wild type (WT) mice. Bioinformatics analysis showed these dysregulated proteins included: oxidative stress-related proteins, synaptic proteins, endoplasmic reticulum (ER) stress-related proteins and apoptosis-related proteins. STRING analysis showed these differential proteins have a well-established interaction network. Based on the proteomic data, we revealed by Western-blot analysis that TRPC1 deletion caused ER stress as evidenced by the dysregulation of GRP78 and PERK activation-related signaling pathway, and elevated oxidative stress as suggested by increased 8-OHdG staining, increased NADH dehydrogenase (ubiquinone) flavoprotein 2 (NDUV2) and decreased protein deglycase (DJ-1), two oxidative stress-related proteins. In addition, we also demonstrated that TRPC1 deletion led to significantly increased apoptosis in striatum with concurrent decrease in both 14-3-3Z and dynamin-1 (D2 dopamine (DA) receptor binding), two apoptosis-related proteins. Taken together, we concluded that TRPC1 deletion might cause striatal neuronal apoptosis by disturbing multiple biological processes (i.e., ER stress, oxidative stress and apoptosis-related signaling). These data suggest that TRPC1 may be a key player in the regulation of striatal cellular survival and death.