Androgen receptor-mediated CD8+ T cell stemness programs drive sex differences in antitumor immunity.

The incidence and mortality rates of many non-reproductive human cancers are generally higher in males than in females. However, the immunological mechanism underlying sexual differences in cancers remains elusive. Here, we demonstrated that sex-related differences in tumor burden depended on adaptive immunity. Male CD8+ T cells exhibited impaired effector and stem cell-like properties compared with female CD8+ T cells. Mechanistically, androgen receptor inhibited the activity and stemness of male tumor-infiltrating CD8+ T cells by regulating epigenetic and transcriptional differentiation programs. Castration combined with anti-PD-L1 treatment synergistically restricted tumor growth in male mice. In humans, fewer male CD8+ T cells maintained a stem cell-like memory state compared with female counterparts. Moreover, AR expression correlated with tumor-infiltrating CD8+ T cell exhaustion in cancer patients. Our findings reveal sex-biased CD8+ T cell stemness programs in cancer progression and in the responses to cancer immunotherapy, providing insights into the development of sex-based immunotherapeutic strategies for cancer treatment.

Fluid nanoporous microinterface enables multiscale-enhanced affinity interaction for tumor-derived extracellular vesicle detection.

Tumor-derived extracellular vesicles (T-EVs) represent valuable markers for tumor diagnosis and treatment guidance. However, nanoscale sizes and the low abundance of marker proteins of T-EVs restrict interfacial affinity reaction, leading to low isolation efficiency and detection sensitivity. Here, we engineer a fluid nanoporous microinterface (FluidporeFace) in a microfluidic chip by decorating supported lipid bilayers (SLBs) on nanoporous herringbone microstructures with a multiscale-enhanced affinity reaction for efficient isolation of T-EVs. At the microscale level, the herringbone micropattern promotes the mass transfer of T-EVs to the surface. At the nanoscale level, nanoporousity can overcome boundary effects for close contact between T-EVs and the interface. At the molecular level, fluid SLBs afford clustering of recognition molecules at the binding site, enabling multivalent binding with an ∼83-fold increase of affinity compared with the nonfluid interface. With the synergetic enhanced mass transfer, interface contact, and binding affinity, FluidporeFace affords ultrasensitive detection of T-EVs with a limit of detection of 10 T-EVs µL-1, whose PD-L1 expression levels successfully distinguish cancer patients from healthy donors. We expect this multiscale enhanced interfacial reaction strategy will inspire the biosensor design and expand liquid biopsy applications, especially for low-abundant targets in clinical samples.

Cellular Localization of FOXO3 Determines Its Role in Cataractogenesis.

The transcription factor forkhead box protein (FOX)-O3 is a core regulator of cellular homeostasis, stress response, and longevity. The cellular localization of FOXO3 is closely related to its function. Herein, the role of FOXO3 in cataract formation was explored. FOXO3 showed nuclear translocation in lens epithelial cells (LECs) arranged in a single layer on lens capsule tissues from both human cataract and N-methyl-N-nitrosourea (MNU)-induced rat cataract, also in MNU-injured human (H)-LEC lines. FOXO3 knockdown inhibited the MNU-induced increase in expression of genes related to cell cycle arrest (GADD45A and CCNG2) and apoptosis (BAK and TP53). H2 is highly effective in reducing oxidative impairments in nuclear DNA and mitochondria. When H2 was applied to MNU-injured HLECs, FOXO3 underwent cleavage by MAPK1 and translocated into mitochondria, thereby increasing the transcription of oxidative phosphorylation-related genes (MTCO1, MTCO2, MTND1, and MTND6) in HLECs. Furthermore, H2 mediated the translocation of FOXO3 from the nucleus to the mitochondria within the LECs of cataract capsule tissues of rats exposed to MNU. This intervention ameliorated MNU-induced cataracts in the rat model. In conclusion, there was a correlation between the localization of FOXO3 and its function in cataract formation. It was also determined that H2 protects HLECs from injury by leading FOXO3 mitochondrial translocation via MAPK1 activation. Mitochondrial FOXO3 can increase mtDNA transcription and stabilize mitochondrial function in HLECs.

In Situ Detection of Nucleic Acids in Extracellular Vesicles via Membrane Fusion.

Extracellular vesicles (EVs) carry diverse biomolecules (e. g., nucleic acids, proteins) for intercellular communication, serving as important markers for diseases. Analyzing nucleic acids derived from EVs enables non-invasive disease diagnosis and prognosis evaluation. Membrane fusion, a fundamental cellular process wherein two lipid membranes merge, facilitates cell communication and cargo transport. Building on this natural phenomenon, recent years have witnessed the emergence of membrane fusion-based strategies for the detection of nucleic acids within EVs. These strategies entail the encapsulation of detection probes within either artificial or natural vesicles, followed by the induction of membrane fusion with EVs to deliver probes. This innovative approach not only enables in situ detection of nucleic acids within EVs but also ensures the maintenance of structural integrity of EVs, thus preventing nucleic acid degradation and minimizing the interference from free nucleic acids. This concept categorizes approaches into universal and targeted membrane fusion strategies, and discusses their application potential, and challenges and future prospects.

KIAA1429 Promotes Nasopharyngeal Carcinoma Progression by Mediating m6A Modification of PTGS2.

Emerging evidence suggests that dysregulation of a N6-methyladenosine (m6A) methyltransferase KIAA1429 participates in the pathogenesis of multiple cancers except for nasopharyngeal carcinoma (NPC). This study is aimed to explore the function of KIAA1429 in NPC progression. The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets were used to confirm the mRNA expression in NPC by bioinformatic analysis. The levels of KIAA1429 and PTGS2 was detected by quantitative reverse transcription polymerase chain reaction and Western blotting. To investigate the effects of KIAA1429/PTGS2 knockdown or overexpression vectors on NPC cell malignancy, cell and animal experiments were performed. Finally, MeRIP and mRNA stability assays were used to verify the m6A modification and mRNA stability, respectively. KIAA1429 was upregulated in NPC tissues and cells. After transfecting KIAA1429 knockdown or overexpression vectors in NPC cells, we proved that KIAA1429 overexpression promoted proliferation, migration, invasion, and tumor growth, whereas KIAA1429 knockdown showed the opposite effect. Our results also indicated that KIAA1429 mediated m6A modification of PTGS2, enhancing PTGS2 mRNA stability in NPC cells. In addition, PTGS2 could also regulate the effects of KIAA1429 on NPC cell malignancy. This study confirmed the oncogenic function of KIAA1429 in NPC through m6A-modification of PTGS2, suggesting that targeting KIAA1429-mediated m6A modification of PTGS2 might provide a new therapeutic strategy for NPC.

The efficacy of platelet rich plasma on women with poor ovarian response: a systematic review and meta-analysis.

BACKGROUND: Platelet-rich plasma (PRP) is a therapeutic approach that is gaining attention for its potential in the treatment of poor ovarian response. This meta-analysis aimed to systematically review and analyze clinical studies to evaluate the impact of PRP on poor responders undergoing ovarian stimulation for IVF. METHODS: A comprehensive search was conducted in electronic databases, including PubMed, Embase, Scopus, Web of Science, and the Cochrane Library to identify relevant studies published in English. The pooled data, such as pregnancy outcome, number of MII oocytes, number of transferable embryos, and ovarian reserve markers were analyzed using R version 4.2.3. RESULTS: A total of 10 trials were enrolled in the present meta-analysis. Following PRP treatment, live birth rate was found to be 16.6% (95% CI 8.8%-26.1%), while clinical pregnancy rate was observed to be 25.4% (95% CI 13.1%-39.9%). PRP pretreatment resulted in a higher number of MII oocytes (MD 1.073, 95% CI 0.720 to 1.427), a higher number of embryos (MD 0.946, 95% CI 0.569 to 1.323), a higher antral follicle count (MD 1.117; 95% CI 0.689 to 1.544), and the change of hormone levels. CONCLUSIONS: Among the studies evaluated in this review, PRP showed promising results in poor responder. Further research is required to clarify the potential role of PRP in female reproductive health.

What is the context? The incidence of poor ovarian response following ovarian stimulation ranges globally from 5.6% to 35.1%.Although various interventions have been implemented in patients with POR, there is a lack of empirical evidence demonstrating the superiority of any of these therapies over one another.Platelet-rich plasma, which is rich in growth factors that have been implicated in cellular growth, differentiation, angiogenesis, and tissue repair, is emerging as a promising therapeutic modality.Limited data determines the viability of PRP as an alternative therapy for POR patients, but further evidence is needed to quantify this effect.What is new? To the best of our knowledge, this is the first systematic review and meta-analysis that investigated the efficacy of PRP on women with POR, including ten trials and 876 patients.This review provides a comprehensive overview of the existing evidence on the utilization of PRP in poor responders, while also emphasizing the primary limitations in the literature and the necessity for future research based on evidence.What is the impact? Among the studies evaluated in this review, PRP showed a potential positive impact on the regulation of sex hormone levels, ovarian response, and pregnancy outcomes.

Community-embedded follow-up management intervention for geriatric primary care: a mixed-methods study of an integrated health services model.

BACKGROUND: To propose a community-embedded follow-up management model to provide health services for elderly patients with osteoporosis who live alone. METHODS: Researchers randomly selected 396 people with osteoporosis living alone from five communities in Nantong, China, for the study. These participants were randomly assigned to control and intervention groups. Twenty-four community physicians in five communities provided professional support based on a community-embedded follow-up management model. Participants completed quantitative questionnaires at baseline and after the 6-month follow-up intervention, and some participants underwent semi-structured face-to-face interviews. The primary outcome is the effectiveness of the community-embedded follow-up management model in improving the quality of life of elderly patients with osteoporosis living alone. Based on an objective quantitative assessment, the qualitative study explains and adds essential components of this community-based follow-up management model. RESULTS: The quantitative study showed that scores in physical functioning, ability to perform daily activities, self-efficacy, and mental status were significantly improved in the intervention group compared to the control group (p < 0.05). The most significant improvements were found in "mental status" (p = 0.012) and "self-care skills" (p = 0.003). The qualitative study reported the essential elements of a community healthcare model for older people living alone with osteoporosis, including professional support, personalized services, social support, and empowerment. CONCLUSIONS: Community-embedded follow-up management meets the need for elderly patients with osteoporosis living alone. It helps to improve health perception, promote physical and mental health, and optimize the quality of life in this population. Personalized services and professional support are two major contributing factors to effective embedded follow-up management in the community.

Hypoxia-Inducible Factor 2α Attenuates Renal Ischemia-Reperfusion Injury by Suppressing CD36-Mediated Lipid Accumulation in Dendritic Cells in a Mouse Model.

BACKGROUND: Hypoxia and hypoxia-inducible factors (HIFs) play essential and multiple roles in renal ischemia-reperfusion injury (IRI). Dendritic cells (DCs) comprise a major subpopulation of the immunocytes in the kidney and are key initiators and effectors of the innate immune responses after IRI. The role of HIF-2α in DCs remains unclear in the context of renal IRI. METHODS: To investigate the importance of HIF-2α in DCs upon renal IRI, we examined the effects of DC-specific HIF-2α ablation in a murine model. Bone marrow-derived DCs (BMDCs) from DC-specific HIF-2α-ablated mice and wild-type mice were used for functional studies and transcriptional profiling. RESULTS: DC-specific ablation of HIF-2α led to hyperactivation of natural killer T (NKT) cells, ultimately exacerbating murine renal IRI. HIF-2α deficiency in DCs triggered IFN-γ and IL-4 production in NKT cells, along with upregulation of type I IFN and chemokine responses that were critical for NKT cell activation. Mechanistically, loss of HIF-2α in DCs promoted their expression of CD36, a scavenger receptor for lipid uptake, increasing cellular lipid accumulation. Furthermore, HIF-2α bound directly to a reverse hypoxia-responsive element (rHRE) in the CD36 promoter. Importantly, CD36 blockade by sulfo-N-succinimidyl oleate (SSO) reduced NKT cell activation and abolished the exacerbation of renal IRI elicited by HIF-2α knockout. CONCLUSIONS: Our study reveals a previously unrecognized role of the HIF-2α/CD36 regulatory axis in rewiring DC lipid metabolism under IRI-associated hypoxia. These findings suggest a potential therapeutic target to resolve long-standing obstacles in treatment of this severe complication.

Real-time analgesic efficacy and factors determining drug requirements of combined spinal-epidural analgesia for labor: a prospective cohort study.

PURPOSE: Combined spinal-epidural analgesia (CSEA) is effective but not sufficient for labor pain. This study was conducted to assess the real-time analgesic efficacy, side effects of anesthetic drug dosage, and maternal satisfaction in labor to provide reference for the optimization of labor analgesia. METHODS: This was a prospective, cohort, single-center study that included 3020 women who received CSEA for labor analgesia. The visual analogue scale (VAS) for labor pain, real-time anesthetic drug dosage, side effects, adverse labor outcomes, factors influencing average drug dosage, and maternal satisfaction with CSEA were assessed. RESULTS: Overall, the VAS labor pain score was lowest at the first hour after the anesthesia was given. After 4 h for primiparas and 3 h for multiparas, the VAS score was greater than 3 but the anesthetic drug dosage did not reach the maximum allowed dosage at the same time. The average anesthetic drug dosage was positively correlated with fever, urinary retention, uterine atony, prolonged active phase, prolonged second stage, assisted vaginal delivery, and postpartum hemorrhage. The average anesthetic drug dosage was the highest in women ≤ 20 years old, those with a body mass index (BMI) ≥ 24.9 kg/m2, and those with a primary or secondary education level. CONCLUSION: Appropriate age guidance and emphasis on education of labor analgesia, weight management during pregnancy, and real-time anesthetic dosage adjustment during labor based on VAS pain score may have positive effects on the satisfaction of labor analgesia. CLINICAL TRIAL NUMBER AND REGISTRY: Clinicaltrials.gov (ChiCTR2100051809).

[Multi-Voiced Narrative of Home-Based Palliative Care:Report of One Case].

Terminally ill patients face multiple difficulties in home care.Home-based palliative care adhering to the concept of whole-person,whole-family,whole-team,and whole-course care is able to meet the needs of terminally ill patients and their families.In this paper,we reported the care history and home-based palliative care process of a patient with end-stage breast tumor and summarized the experience,aiming to provide reference for the future work of home-based palliative care.

MicroRNA-668-3p inhibits myoblast proliferation and differentiation by targeting Appl1.

BACKGROUND: Skeletal muscle is the largest tissue in the body, and it affects motion, metabolism and homeostasis. Skeletal muscle development comprises myoblast proliferation, fusion and differentiation to form myotubes, which subsequently form mature muscle fibres. This process is strictly regulated by a series of molecular networks. Increasing evidence has shown that noncoding RNAs, especially microRNAs (miRNAs), play vital roles in regulating skeletal muscle growth. Here, we showed that miR-668-3p is highly expressed in skeletal muscle. METHODS: Proliferating and differentiated C2C12 cells were transfected with miR-668-3p mimics and/or inhibitor, and the mRNA and protein levels of its target gene were evaluated by RT‒qPCR and Western blotting analysis. The targeting of Appl1 by miR-668-3p was confirmed by dual luciferase assay. The interdependence of miR-668-3p and Appl1 was verified by cotransfection of C2C12 cells. RESULTS: Our data reveal that miR-668-3p can inhibit myoblast proliferation and myogenic differentiation. Phosphotyrosine interacting with PH domain and leucine zipper 1 (Appl1) is a target gene of miR-668-3p, and it can promote myoblast proliferation and differentiation by activating the p38 MAPK pathway. Furthermore, the inhibitory effect of miR-668-3p on myoblast cell proliferation and myogenic differentiation could be rescued by Appl1. CONCLUSION: Our results indicate a new mechanism by which the miR-668-3p/Appl1/p38 MAPK pathway regulates skeletal muscle development.

Encoded Fusion-Mediated MicroRNA Signature Profiling of Tumor-Derived Extracellular Vesicles for Pancreatic Cancer Diagnosis.

MicroRNAs (miRNAs) in tumor-derived extracellular vesicles (tEVs) are important cancer biomarkers for cancer screening and early diagnosis. Multiplex detection of miRNAs in tEVs facilitates accurate diagnosis but remains a challenge. Herein, we propose an encoded fusion strategy to profile the miRNA signature in tEVs for pancreatic cancer diagnosis. A panel of encoded-targeted-fusion beads was fabricated for the selective recognition and fusion of tEVs, with the turn-on fluorescence signals of molecule beacons for miRNA quantification and barcode signals for miRNA identification using readily accessible flow cytometers. Using this strategy, six types of pancreatic-cancer-associated miRNAs can be profiled in tEVs from 2 µL plasma samples (n = 36) in an isolation-free and lysis-free manner with only 2 h of processing, offering a high accuracy (98%) to discriminate pancreatic cancer, pancreatitis, and healthy donors. This encoded fusion strategy exhibits great potential for multiplex profiling of miRNA in tEVs, offering new avenues for cancer diagnosis and screening.

The PI3K-Akt-mTOR pathway mediates renal pericyte-myofibroblast transition by enhancing glycolysis through HKII.

BACKGROUND: Pericyte-myofibroblast transition (PMT) has been confirmed to contribute to renal fibrosis in several kidney diseases, and transforming growth factor-ß1 (TGF-ß1) is a well-known cytokine that drives PMT. However, the underlying mechanism has not been fully established, and little is known about the associated metabolic changes. METHODS: Bioinformatics analysis was used to identify transcriptomic changes during PMT. PDGFRß + pericytes were isolated using MACS, and an in vitro model of PMT was induced by 5 ng/ml TGF-ß1. Metabolites were analyzed by ultraperformance liquid chromatography (UPLC) and tandem mass spectrometry (MS). 2-Deoxyglucose (2-DG) was used to inhibit glycolysis via its actions on hexokinase (HK). The hexokinase II (HKII) plasmid was transfected into pericytes for HKII overexpression. LY294002 or rapamycin was used to inhibit the PI3K-Akt-mTOR pathway for mechanistic exploration. RESULTS: An increase in carbon metabolism during PMT was detected through bioinformatics and metabolomics analysis. We first detected increased levels of glycolysis and HKII expression in pericytes after stimulation with TGF-ß1 for 48 h, accompanied by increased expression of α-SMA, vimentin and desmin. Transdifferentiation was blunted when pericytes were pretreated with 2-DG, an inhibitor of glycolysis. The phosphorylation levels of PI3K, Akt and mTOR were elevated during PMT, and after inhibition of the PI3K-Akt-mTOR pathway with LY294002 or rapamycin, glycolysis in the TGF-ß1-treated pericytes was decreased. Moreover, PMT and HKII transcription and activity were blunted, but the plasmid-mediated overexpression of HKII rescued PMT inhibition. CONCLUSIONS: The expression and activity of HKII as well as the level of glycolysis were increased during PMT. Moreover, the PI3K-Akt-mTOR pathway regulates PMT by increasing glycolysis through HKII regulation.

Multi-omics analyses of serum metabolome, gut microbiome and brain function reveal dysregulated microbiota-gut-brain axis in bipolar depression.

The intricate processes of microbiota-gut-brain communication in modulating human cognition and emotion, especially in the context of mood disorders, have remained elusive. Here we performed faecal metagenomic, serum metabolomics and neuroimaging studies on a cohort of 109 unmedicated patients with depressed bipolar disorder (BD) patients and 40 healthy controls (HCs) to characterise the microbial-gut-brain axis in BD. Across over 12,000 measured metabolic features, we observed a large discrepancy (73.54%) in the serum metabolome between BD patients and HCs, spotting differentially abundant microbial-derived neuroactive metabolites including multiple B-vitamins, kynurenic acid, gamma-aminobutyric acid and short-chain fatty acids. These metabolites could be linked to the abundance of gut microbiota presented with corresponding biosynthetic potentials, including Akkermansia muciniphila, Citrobacter spp. (Citrobacter freundii and Citrobacter werkmanii), Phascolarctobacterium spp., Yersinia spp. (Yersinia frederiksenii and Yersinia aleksiciae), Enterobacter spp. (Enterobacter cloacae and Enterobacter kobei) and Flavobacterium spp. Based on functional neuroimaging, BD-related neuroactive microbes and metabolites were discovered as potential markers associated with BD-typical features of functional connectivity of brain networks, hinting at aberrant cognitive function, emotion regulation, and interoception. Our study combines gut microbiota and neuroactive metabolites with brain functional connectivity, thereby revealing potential signalling pathways from the microbiota to the gut and the brain, which may have a role in the pathophysiology of BD.

Aptamer-Based Detection of Circulating Targets for Precision Medicine.

The past decade has witnessed ongoing progress in precision medicine to improve human health. As an emerging diagnostic technique, liquid biopsy can provide real-time, comprehensive, dynamic physiological and pathological information in a noninvasive manner, opening a new window for precision medicine. Liquid biopsy depends on the sensitive and reliable detection of circulating targets (e.g., cells, extracellular vesicles, proteins, microRNAs) from body fluids, the performance of which is largely governed by recognition ligands. Aptamers are single-stranded functional oligonucleotides, capable of folding into unique tertiary structures to bind to their targets with superior specificity and affinity. Their mature evolution procedure, facile modification, and affinity regulation, as well as versatile structural design and engineering, make aptamers ideal recognition ligands for liquid biopsy. In this review, we present a broad overview of aptamer-based liquid biopsy techniques for precision medicine. We begin with recent advances in aptamer selection, followed by a summary of state-of-the-art strategies for multivalent aptamer assembly and aptamer interface modification. We will further describe aptamer-based micro-/nanoisolation platforms, aptamer-enabled release methods, and aptamer-assisted signal amplification and detection strategies. Finally, we present our perspectives regarding the opportunities and challenges of aptamer-based liquid biopsy for precision medicine.

HRCT quantitative analysis of airway remodeling and airway trapping in the small airway asthma phenotype and its correlation with pulmonary function.

OBJECTIVES: We aimed to explore whether large airway remodeling and small airway structural changes exist in subjects with small airway asthma phenotype and to evaluate the relationships between quantitative high-resolution computed tomography (qHRCT) parameters and lung function. METHODS: We enrolled 15 subjects with small airway asthma phenotype and 18 healthy controls. The two groups were matched by age, sex and body square area (BSA) with propensity score matching (PSM). Pulmonary function and qHRCT parameters [wall thickness (WT), wall area (WA), lumen area (LA), wall area percentage (WA%) of the 4th-6th generations in the right upper lobe apical segmental bronchus (RB1), adjusted by BSA, WT/BSA, WA/BSA, and LA/BSA, relative volume change -860 HU to -950 HU (RVC-860 to -950) and the expiration to inspiration ratio of mean lung density (MLDE/I)) were compared between the groups. Correlation analysis was employed to assess the relationship between qHRCT parameters and pulmonary function. RESULTS: The small airway asthma phenotype had significantly higher WA%, RVC-860 to -950 and MLDE/I and lower LA/BSA than the healthy control. Additionally, we found moderate to strong correlations between impulse oscillation (IOS) indices and WA6% and WT6/BSA. No significant correlation was found between bronchial parameters and air trapping parameters (p > 0.05). CONCLUSIONS: Combining physiological tests with imaging approaches can lead to better evaluation of small airway disfunction (SAD) in asthmatic patients. Additionally, despite nonexistent airflow obstruction in patients with small airway asthma phenotype, large airway remodeling and small airway structural changes may appear simultaneously in the early stage of disease.

Cxcl10 deficiency attenuates renal interstitial fibrosis through regulating epithelial-to-mesenchymal transition.

IFN-γ-inducible protein 10 (IP-10, CXCL10) has been widely demonstrated to be involved in multiple kidney pathological processes. However, the role of CXCL10 in renal fibrosis remains unclear. In this study, Cxcl10-deficient (Cxcl10-/-) mice were used to generate the unilateral ureteral obstruction (UUO) model. The level of renal fibrosis and inflammatory cell infiltration was examined in vivo and the effects of CXCL10 on EMT process of HK-2 cells was investigated in vitro. We observed that the injury degree of renal tissue and the collagen deposition levels were lighter and the expression of α-SMA, collagen I and fibronectin was significantly reduced in Cxcl10-/- mice, while the expression of E-cadherin was increased. However, interstitial F4/80-positive macrophages and CD4-positive T lymphocytes were unaffected by knockout of Cxcl10. Furthermore, IFN-γ or CXCL10 stimulation could obviously promote the expression of α-SMA, collagen I, fibronectin and reduce the expression of E-cadherin in HK-2 cells, which could be inhibited by transfection of Cxcl10-siRNA. Our findings suggested Cxcl10 knockout could reduce renal dysfunction and inhibit renal fibrosis through regulating EMT process of renal tubular epithelial cells in murine UUO model. These results may provide a novel insight into the mechanism and a potential therapy target of renal fibrosis.

Evolution of carbapenem resistance in klebsiella pneumoniae and escherichia coli carrying blaNDM-1 gene: imipenem exposure results in sustained resistance memory of strains in vitro.

BACKGROUND: Antibiotics exert an outstanding selective pressure on bacteria, forcing their chromosomal gene mutations and drug resistance genes to spread. The objective of this study is to evaluate the expression of the New Delhi Metallo-ß-Lactamase-1 gene (blaNDM-1) in the clinical isolate (Klebsiella pneumoniae TH-P12158), transformant strains Escherichia coli BL21 (DE3)-blaNDM-1, and Escherichia coli DH5α- blaNDM-1 when exposed to imipenem. METHODS: ß-Lactamase genes (blaSHV, blaTEM-1, blaCTX-M-9, blaIMP, blaNDM-1, blaKPC, blaOXA, blaGES, and blaDHA) from randomly selected carbapenems-sensitive K.pneumoniae (n = 20) and E.coli (n = 20) strains were amplified by PCR. The recombinant plasmid of pET-28a harboring blaNDM-1 was transformed into E.coli BL21 (DE3) and E.coli DH5α by electroporation. The resistance phenotype and higher blaNDM-1 expression in K.pneumoniae TH-P12158, transformant E.coli BL21 (DE3)-blaNDM-1, and E.coli DH5α-blaNDM-1 were observed when exposed to imipenem with grade increasing, decreasing, and canceling doses, respectively. RESULTS: After being exposed to different doses of imipenem, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of antimicrobial drugs and blaNDM-1 expression of strains increased, which was positively correlated with doses of imipenem. On the contrary, with the decrease or cancellation of imipenem doses, the blaNDM-1 expression was deteriorated, while the MIC and MBC values remained relatively stable. These results demonstrated that low doses of imipenem (˂MIC) could press blaNDM-1 positive strains producing stable drug resistance memory and altered blaNDM-1 expression. CONCLUSIONS: Low doses of imipenem could press blaNDM-1 positive strains producing sustained resistance memory and altered blaNDM-1 expression. In particular, the positive correlation between the resistance genes expression and antibiotics exposure shows promising guiding significance for clinical medication.

14-3-3ζ inhibits maladaptive repair in renal tubules by regulating YAP and reduces renal interstitial fibrosis.

Acute kidney injury (AKI) refers to a group of common clinical syndromes characterized by acute renal dysfunction, which may lead to chronic kidney disease (CKD), and this process is called the AKI-CKD transition. The transcriptional coactivator YAP can promote the AKI-CKD transition by regulating the expression of profibrotic factors, and 14-3-3 protein zeta (14-3-3ζ), an important regulatory protein of YAP, may prevent the AKI-CKD transition. We established an AKI-CKD model in mice by unilateral renal ischemia-reperfusion injury and overexpressed 14-3-3ζ in mice using a fluid dynamics-based gene transfection technique. We also overexpressed and knocked down 14-3-3ζ in vitro. In AKI-CKD model mice, 14-3-3ζ expression was significantly increased at the AKI stage. During the development of chronic disease, the expression of 14-3-3ζ tended to decrease, whereas active YAP was consistently overexpressed. In vitro, we found that 14-3-3ζ can combine with YAP, promote the phosphorylation of YAP, inhibit YAP nuclear translocation, and reduce the expression of fibrosis-related proteins. In an in vivo intervention experiment, we found that the overexpression of 14-3-3ζ slowed the process of renal fibrosis in a mouse model of AKI-CKD. These findings suggest that 14-3-3ζ can affect the expression of fibrosis-related proteins by regulating YAP, inhibit the maladaptive repair of renal tubular epithelial cells, and prevent the AKI-CKD transition.