Biomarker study of symptomatic intracranial atherosclerotic stenosis in patients with acute ischemic stroke

ObjectiveAcute ischemic stroke (AIS) is characterized by high rates of morbidity, disability, mortality, and recurrence, often leaving patients with varying degrees of sequelae. Symptomatic intracranial atherosclerotic stenosis (sICAS) is a significant contributor to AIS pathogenesis and recurrence. The formation and progression of sICAS are influenced by pathways such as lipid metabolism and inflammatory response. Given its high risk of clinical recurrence, timely assessment of intracranial vascular stenosis in AIS is crucial for diagnosing sICAS, treating stroke, and preventing stroke recurrence.MethodsFourteen AIS patients were divided into stenosis and control groups based on the presence or absence of intracranial vessel stenosis. Initially, 4D Label-free proteome quantification technology was employed for mass spectrometry analysis to identify differential proteins between the groups. Subsequently, functional enrichment analysis, including GO classification, KEGG pathway, and Domain, revealed trends related to differential proteins. The STRING (v.11.5) protein interaction network database was used to identify differential protein interactions and target proteins. Finally, parallel reaction monitoring (PRM) validated the selected target proteins.ResultsMass spectrometry identified 1,096 proteins, with 991 being quantitatively comparable. Using a p-value <0.05 and differential expression change thresholds of >1.3 for significant up-regulation and < 1/1.3 for significant down-regulation, 46 differential proteins were identified: 24 significantly up-regulated and 22 significantly down-regulated. PRM experiments validated five proteins related to lipid metabolism and inflammatory response: namely alpha-2-macroglobulin (A2M), lipopolysaccharide-binding protein (LBP), cathepsin G (CTSG), cystatin (CST)3, and fatty acid-binding protein (FABP)1.ConclusionThe detection of changes in these five proteins in AIS patients can aid in the diagnosis of sICAS, inform stroke treatment, and assist in preventing stroke recurrence. Moreover, it can contribute to the development of drugs for preventing AIS recurrence by integrating traditional Chinese and Western medicine

Long-term exposure of mice to nucleoside analogues disrupts mitochondrial DNA maintenance in cortical neurons.

Nucleoside analogue reverse transcriptase inhibitor (NRTI), an integral component of highly active antiretroviral therapy (HAART), was widely used to inhibit HIV replication. Long-term exposure to NRTIs can result in mitochondrial toxicity which manifests as lipoatrophy, lactic acidosis, cardiomyopathy and myopathy, as well as polyneuropathy. But the cerebral neurotoxicity of NRTIs is still not well known partly due to the restriction of blood-brain barrier (BBB) and the complex microenvironment of the central nervous system (CNS). In this study, the Balb/c mice were administered 50 mg/kg stavudine (D4T), 100 mg/kg zidovudine (AZT), 50 mg/kg lamivudine (3TC) or 50 mg/kg didanosine (DDI) per day by intraperitoneal injection, five days per week for one or four months, and primary cortical neurons were cultured and exposed to 25 µM D4T, 50 µM AZT, 25 µM 3TC or 25 µM DDI for seven days. Then, single neuron was captured from mouse cerebral cortical tissues by laser capture microdissection. Mitochondrial DNA (mtDNA) levels of the primary cultured cortical neurons, and captured neurons or glial cells, and the tissues of brains and livers and muscles were analyzed by relative quantitative real-time PCR. The data showed that mtDNA did not lose in both NRTIs exposed cultured neurons and one month NRTIs treated mouse brains. In four months NRTIs treated mice, brain mtDNA levels remained unchanged even if the mtDNA levels of liver (except for 3TC) and muscle significantly decreased. However, mtDNA deletion was significantly higher in the captured neurons from mtDNA unchanged brains. These results suggest that long-term exposure to NRTIs can result in mtDNA deletion in mouse cortical neurons

Long-term exposure to nucleoside analogues did not affect total mtDNA levels of mouse cerebral cortex as measured by COXII specific primers and probes.

<p>Compared with control, total mtDNA copies significantly decreased in livers of the mice treated with D4T (50 mg/kg), AZT (100 mg/kg) and DDI (50 mg/kg) for four months, but total mtDNA did not change in livers of the mice treated with 3TC (50 mg/kg) for four months. Total mtDNA significantly decreased in muscles of the mice treated with D4T (50 mg/kg), AZT (100 mg/kg), 3TC (50 mg/kg) and DDI (50 mg/kg) for four months. But total mtDNA copies did not lose in brain tisssues of the mice treated with DDI, D4T, AZT and 3TC for four months. Further, mtDNA had even compensatory increased in D4T group and 3TC group (“*” denoted <i>p</i><0.05, “**” denoted <i>p</i><0.01).</p

Long-term exposure to nucleoside analogues increased mtDNA loss of mouse cerebral cortical neurons.

<p>A. Typical images of Laser Capture Microdissection before and after microdissection (×200 to ×400 magnification). B. Compared with control, mtDNA significantly decreased in captured neurons from brain tisssues of the mice treated with D4T (50 mg/kg), AZT (100 mg/kg), 3TC (50 mg/kg) and DDI (50 mg/kg) for four months as measured by COXII specific primers and probes (“*” denoted <i>p</i><0.05, “**” denoted <i>p</i><0.01).</p

Fusobacterium nucleatum promotes tumor progression in KRAS p.G12D-mutant colorectal cancer by binding to DHX15

Abstract Fusobacterium nucleatum (F. nucleatum) promotes intestinal tumor growth and its relative abundance varies greatly among patients with CRC, suggesting the presence of unknown, individual-specific effectors in F. nucleatum-dependent carcinogenesis. Here, we identify that F. nucleatum is enriched preferentially in KRAS p.G12D mutant CRC tumor tissues and contributes to colorectal tumorigenesis in Villin-Cre/Kras G12D+/- mice. Additionally, Parabacteroides distasonis (P. distasonis) competes with F. nucleatum in the G12D mouse model and human CRC tissues with the KRAS mutation. Orally gavaged P. distasonis in mice alleviates the F. nucleatum-dependent CRC progression. F. nucleatum invades intestinal epithelial cells and binds to DHX15, a protein of RNA helicase family expressed on CRC tumor cells, mechanistically involving ERK/STAT3 signaling. Knock out of Dhx15 in Villin-Cre/Kras G12D+/- mice attenuates the CRC phenotype. These findings reveal that the oncogenic effect of F. nucleatum depends on somatic genetics and gut microbial ecology and indicate that personalized modulation of the gut microbiota may provide a more targeted strategy for CRC treatment

Long-term nucleoside analogue exposures mainly induced mouse neuronal mtDNA major arc deletion.

<p>A. The number of captured neuron ND4 (mtDNA major arc) copies significantly decreased in the mice treated with D4T (50 mg/kg), AZT (100 mg/kg), 3TC (50 mg/kg) or DDI (50 mg/kg) for four months. But only AZT group had a decline in ND1 (mtDNA minor arc) copies. B. The numbers of ND4 and ND1 copies from captured glial cells had no significant changes in all four–month-NRTI-treatment groups except for D4T group in which the number of ND4 copies increased instead of reduction (“*” denoted <i>p</i><0.05, “**” denoted <i>p</i><0.01).</p