Rolling circle transcription and CRISPR/Cas12a-assisted versatile bicyclic cascade amplification assay for sensitive uracil-DNA glycosylase detection.

Uracil-DNA glycosylase (UDG) is pivotal in maintaining genome integrity and aberrant expressed UDG is highly relevant to numerous diseases. Sensitive and accurate detecting UDG is critically significant for early clinical diagnosis. In this research, we demonstrated a sensitive UDG fluorescent assay based on rolling circle transcription (RCT)/CRISPR/Cas12a-assisted bicyclic cascade amplification strategy. Target UDG catalyzed to remove uracil base of DNA dumbbell-shape substrate probe (SubUDG) to produce an apurinic/apyrimidinic (AP) site, at which SubUDG was cleaved by apurinic/apyrimidinic endonuclease (APE1) subsequently. The exposed 5'-PO4 was ligated with the free 3'-OH terminus to form an enclosed DNA dumbbell-shape substrate probe (E-SubUDG). E-SubUDG functioned as a template can actuate T7 RNA polymerase-mediated RCT signal amplification, generating multitudes of crRNA repeats. The resultant Cas12a/crRNA/activator ternary complex activated the activity of Cas12a, causing a significantly enhanced fluorescence output. In this bicyclic cascade strategy, target UDG was amplified via RCT and CRISPR/Cas12a, and the whole reaction was completed without complex procedures. This method enabled sensitive and specific monitor UDG down to 0.0005 U/mL, screen corresponding inhibitors, and analyze endogenous UDG in A549 cells at single-cell level. Importantly, this assay can be extended to analyze other DNA glycosylase (hAAG and Fpg) by altering the recognition site in DNA substrates probe rationally, thereby offering a potent tool for DNA glycosylase-associated clinical diagnosis and biomedical research.

Nanopolyphenol rejuvenates microglial surveillance of multiple misfolded proteins through metabolic reprogramming.

Microglial surveillance plays an essential role in clearing misfolded proteins such as amyloid-beta, tau, and α-synuclein aggregates in neurodegenerative diseases. However, due to the complex structure and ambiguous pathogenic species of the misfolded proteins, a universal approach to remove the misfolded proteins remains unavailable. Here, we found that a polyphenol, α-mangostin, reprogrammed metabolism in the disease-associated microglia through shifting glycolysis to oxidative phosphorylation, which holistically rejuvenated microglial surveillance capacity to enhance microglial phagocytosis and autophagy-mediated degradation of multiple misfolded proteins. Nanoformulation of α-mangostin efficiently delivered α-mangostin to microglia, relieved the reactive status and rejuvenated the misfolded-proteins clearance capacity of microglia, which thus impressively relieved the neuropathological changes in both Alzheimer's disease and Parkinson's disease model mice. These findings provide direct evidences for the concept of rejuvenating microglial surveillance of multiple misfolded proteins through metabolic reprogramming, and demonstrate nanoformulated α-mangostin as a potential and universal therapy against neurodegenerative diseases.

Recombinant High-Density Lipoprotein Boosts the Therapeutic Efficacy of Mild Hypothermia in Traumatic Brain Injury.

Traumatic brain injury (TBI) leads to neuropsychiatric symptoms and increased risk of neurodegenerative disorders. Mild hypothermia is commonly used in patients suffering from severe TBI. However, its effect for long-term protection is limited, mostly because of its insufficient anti-inflammatory and neuroprotective efficacy and restricted treatment duration. Recombinant high-density lipoprotein (rHDL), which possesses anti-inflammatory and antioxidant activity and blood-brain barrier (BBB) permeability, was expected to potentially strengthen the therapeutic effect of mild hypothermia in TBI treatment. To test this hypothesis and optimize the regimen for combination therapy, the efficacy of mild hypothermia plus concurrent or sequential rHDL on oxidative stress, inflammatory reaction, and cell survival in the damaged brain cells was evaluated. It was found that the effect of combining mild hypothermia with concurrent rHDL was modest, as mild hypothermia inhibited the cellular uptake and lesion-site-targeting delivery of rHDL. In contrast, the combination of mild hypothermia with sequential rHDL more powerfully improved the anti-inflammatory and antioxidant activities, promoted nerve cell survival and BBB restoration, and ameliorated neurologic changes, which thus remarkably restored the spatial learning and memory ability of TBI mice. Collectively, these findings suggest that rHDL may serve as a novel nanomedicine for adjunctive therapy of TBI and highlight the importance of timing of combination therapy for optimal treatment outcome.

Research progress regarding long-chain non-coding RNA in lung cancer: a narrative review.

Background and Objective: Lung cancer is the main cause of cancer-related death worldwide, and its incidence rate is high. Traditional methods of lung cancer screening, such as those based on X-ray, low-dose computed tomography (LDCT), positron emission computed tomography (PET/CT), electronic bronchoscopy, and serum tumor markers were not satisfied with the urgent need in improving the patient survival rate. Thus, biomarkers for early diagnosis and prognosis of lung cancer are extremely needed. Studies have identified a variety of long-chain non-coding RNAs (lncRNAs) that are expressed at abnormal levels in patients with lung cancer which was believed as a potential biomarker for the diagnosis and prognostic evaluation of lung cancer. This review aims to discuss the role of lncRNAs in non-small cell lung cancer (NSCLC), so as to provide insights into the prognosis of lung cancer. Methods: We searched PubMed database of the related scientific researches with outcomes from 09/16/2011 to 05/02/2022 focusing on lncRNA application in lung cancer via searching terms of "lncRNA AND lung cancer", "lncRNA AND non-small cell lung cancer", "lncRNA AND drug resistance", "lncRNA AND radio sensitivity". Published articles written in English available to readers were considered. Key Content and Findings: We summarized significantly differentially-expressed lncRNAs in lung cancer tissues compared with healthy individuals and normal tissues which would become potential biomarkers for lung cancer diagnosis and therapeutic target as a non-invasive detection method. Conclusions: LncRNAs might be valuable potential diagnostic biomarkers of lung cancer progression.

N-acetylcysteine Ameliorates Vancomycin-induced Nephrotoxicity by Inhibiting Oxidative Stress and Apoptosis in the in vivo and in vitro Models.

Background: Oxidative stress-related apoptosis is considered as the key mechanism implicated in the pathophysiology of nephrotoxicity with vancomycin (VCM) therapy. We evaluated the possible effects of N-acetylcysteine (NAC) on VCM-induced nephrotoxicity and the underlying mechanism. Methods: VCM-induced nephrotoxicity was established using HK-2 cells and SD rats and observed by measuring cell survival, kidney histological changes, renal function and kidney injury related markers (KIM-1 and NGAL). Oxidative stress, renal cell apoptosis and the involved signaling pathways were also evaluated. Results: In model rats, NAC could protect against VCM-induced acute kidney injury with histological damage, renal dysfunction, and increased Cre and BUN levels. In HK-2 cells, VCM-induced decreased cell viability was restored by NAC. In addition, increased expression of caspase-3, KIM-1 and NGAL suffering from VCM was also reversed by NAC in vivo and in vitro. NAC inhibited ROS production, decreased cell apoptosis by decreasing the Bax/Bcl-2 ratio and caspase-3 expression in HK-2 cells and regulated oxidative stress indicators in the kidney by decreasing GSH, SOD and CAT activity and increasing MDA levels. Furthermore, NAC could effectively reverse VCM-associated increased P38 MAPK/JNK phosphorylation. Conclusions: The results demonstrated that NAC had a protective effect against nephrotoxicity from VCM by inhibiting oxidative stress and apoptosis via P38 MAPK/JNK.

Lipoprotein-biomimetic nanostructure enables efficient targeting delivery of siRNA to Ras-activated glioblastoma cells via macropinocytosis.

Hyperactivated Ras regulates many oncogenic pathways in several malignant human cancers including glioblastoma and it is an attractive target for cancer therapies. Ras activation in cancer cells drives protein internalization via macropinocytosis as a key nutrient-gaining process. By utilizing this unique endocytosis pathway, here we create a biologically inspired nanostructure that can induce cancer cells to 'drink drugs' for targeting activating transcription factor-5 (ATF5), an overexpressed anti-apoptotic transcription factor in glioblastoma. Apolipoprotein E3-reconstituted high-density lipoprotein is used to encapsulate the siRNA-loaded calcium phosphate core and facilitate it to penetrate the blood-brain barrier, thus targeting the glioblastoma cells in a macropinocytosis-dependent manner. The nanostructure carrying ATF5 siRNA exerts remarkable RNA-interfering efficiency, increases glioblastoma cell apoptosis and inhibits tumour cell growth both in vitro and in xenograft tumour models. This strategy of targeting the macropinocytosis caused by Ras activation provides a nanoparticle-based approach for precision therapy in glioblastoma and other Ras-activated cancers.

Biomimetic ApoE-Reconstituted High Density Lipoprotein Nanocarrier for Blood-Brain Barrier Penetration and Amyloid Beta-Targeting Drug Delivery.

Amyloid beta (Aß) and its aggregation forms in the brain have been suggested as key targets for the therapy of Alzheimer's disease (AD). Therefore, the development of nanocarriers that possess both blood-brain barrier permeability and Aß-targeting ability is of great importance for the intervention of AD. Here we constructed a biomimetic nanocarrier named apolipoprotein E (ApoE)-reconstituted high density lipoprotein nanocarrier (ANC) from recombinant ApoE and synthetic lipids to achieve the above goals. α-Mangostin (α-M), a polyphenolic agent that can inhibit the formation of Aß oligomers and fibrils and accelerate Aß cellular degradation, was used as the model drug. Compared with the control liposome, ANC demonstrated about 54-fold higher cellular uptake in brain endothelial cell line in vitro in an ApoE-dependent manner and much higher brain delivery efficiency in vivo. Confocal microscopy analysis witnessed the penetration of ANC across the brain vessels and its accumulation at the surrounding of Aß aggregates. Following the loading of α-M, the Aß-binding affinity of the nanoformulation (ANC-α-M) was not reduced but even enhanced. The effect of ANC-α-M on facilitating the microglia-mediated uptake and degradation of Aß1-42 was enhanced by 336% and 29-fold when compared with that of the nontreated control and also much higher than that of ANC. Following intravenous administration for 2 to 4 weeks, ANC-α-M exhibited the most efficient efficacy in decreasing amyloid deposition, attenuating microgliosis, and rescuing memory defect in SAMP8 mice, an AD mouse model. Taken together, the findings of this work provided strong evidence that the ApoE-based biomimetic nanocarrier could provide a promising platform for brain drug delivery toward the treatment of AD.

High-density lipoprotein-biomimetic nanocarriers for glioblastoma-targeting delivery: the effect of shape.

Rational design of the physicochemical properties of nanocarriers can optimize their pharmacokinetics, biodistribution, intratumoral penetration and tumor bioavailability. In particular, particle shape is one of the crucial parameters that can impact the circulation time, tumor accumulation and tumor cell internalization of nanocarrier. Biomimetic reconstituted high-density lipoprotein (rHDL), by mimicking the endogenous shape and structure of high-density lipoprotein, has been indicated as a promising tumor-targeting nanoparticulate drug delivery system whereas the effect of shape on tumor-targeting efficiency has not been fully evaluated. Herein, we constructed apolipoprotein E-based biomimetic rHDL in both discoidal form (d-rHDL) and spherical form (s-rHDL), and compared their efficiency in glioblastoma multiforme (GBM)-targeting delivery. s-rHDL showed higher cellular association in GBM cells especially at a high exposure dosage or after a long incubation time. Moreover, it exhibited deeper penetration in 3D GBM spheroids in vitro and higher accumulation at the GBM site in vivo with the GBM-targeting accumulation of s-rHDL increased by 73% when compared with that of d-rHDL at 24 h post-injection. The findings collectively indicated that s-rHDL might serve as a more efficient nanocarrier for glioblastoma-targeting drug delivery.

GM1-Modified Lipoprotein-like Nanoparticle: Multifunctional Nanoplatform for the Combination Therapy of Alzheimer's Disease.

Alzheimer's disease (AD) exerts a heavy health burden for modern society and has a complicated pathological background. The accumulation of extracellular ß-amyloid (Aß) is crucial in AD pathogenesis, and Aß-initiated secondary pathological processes could independently lead to neuronal degeneration and pathogenesis in AD. Thus, the development of combination therapeutics that can not only accelerate Aß clearance but also simultaneously protect neurons or inhibit other subsequent pathological cascade represents a promising strategy for AD intervention. Here, we designed a nanostructure, monosialotetrahexosylganglioside (GM1)-modified reconstituted high density lipoprotein (GM1-rHDL), that possesses antibody-like high binding affinity to Aß, facilitates Aß degradation by microglia, and Aß efflux across the blood-brain barrier (BBB), displays high brain biodistribution efficiency following intranasal administration, and simultaneously allows the efficient loading of a neuroprotective peptide, NAP, as a nanoparticulate drug delivery system for the combination therapy of AD. The resulting multifunctional nanostructure, αNAP-GM1-rHDL, was found to be able to protect neurons from Aß(1-42) oligomer/glutamic acid-induced cell toxicity better than GM1-rHDL in vitro and reduced Aß deposition, ameliorated neurologic changes, and rescued memory loss more efficiently than both αNAP solution and GM1-rHDL in AD model mice following intranasal administration with no observable cytotoxicity noted. Taken together, this work presents direct experimental evidence of the rational design of a biomimetic nanostructure to serve as a safe and efficient multifunctional nanoplatform for the combination therapy of AD.

Phenylmethanesulfonyl fluoride pretreatment stabilizes plasma lipidome in lipidomic and metabolomic analysis.

Though it is standard practice to test the stability of analytes in the matrix for routine bioanalytical method, stability evaluation is always impractical and skipped in untargeted lipidomic and metabolomic analysis because analytes in these studies are enormous, diverse and sometimes unknown. Lipidome represents a major class of plasma metabolome and shows great potential to be diagnostic and prognostic biomarkers. However, lipidome also faces stability problems because plasma contains kinds of lipid degradation enzyme. Here, using liquid chromatography time of flight mass spectrometry based lipidomic methodology, plasma levels of various lipids including triglyceride (TG), diglyceride (DG), free fatty acid (FFA), phosphatidylethanolamine (PE) phosphatidylcholine (PC), lyso-phosphatidylcholine (LPC), lyso-phosphatidylethanolamine (LPE), and sphingomyelin (SM) were dynamically determined within 4 h at ambient temperature. In mouse and rat plasma, the levels of most TG, DG, PC and PE species significantly decreased with respect to time, whereas those of LPC, LPE and FFA significantly increased with respect to time. However, such changes did not occur in human plasma, thus indicating hepatic lipase and esterase might involve in the species-specified degradation of lipid classes in plasma. Phenylmethanesulfonyl fluoride (PMSF) pretreatment prevented such lipidome instability in mouse plasma. The results suggested the instability of plasma lipidome should be highly concerned, and the enhancement of ex vivo stability of plasma lipidome could enable more reliable clinical translation of lipidomic data for biomarker discovery.