Rapid identification of SARS-CoV-2 variants using stable high-frequency mutation sites.

Respiratory infectious viruses, including SARS-CoV-2, undergo rapid genetic evolution, resulting in diverse subtypes with complex mutations. Detecting and differentiating these subtypes pose significant challenges in respiratory virus surveillance. To address these challenges, we integrated ARMS-PCR with molecular beacon probes, allowing selective amplification and discrimination of subtypes based on adjacent mutation sites. The method exhibited high specificity and sensitivity, detecting as low as 104 copies/mL via direct fluorescence analysis and ~106 copies/mL using real-time PCR. Our robust detection approach offers a reliable and efficient solution for monitoring evolving respiratory infections, aiding early diagnosis and control measures. Further research could extend its application to other respiratory viruses and optimize its implementation in clinical settings.

Unraveling the role of CD24 in Hepatocellular carcinoma: Involvement of inactivated Hippo signaling and SOX4-mediated regulation.

Hepatocellular carcinoma (HCC) is a prevalent type of liver cancer, and CD24 gene is reportedly involved in HCC progression. However, the precise regulatory mechanisms of CD24 in HCC remain unclear. In this study, we established a primary HCC mouse model and observed that CD24, induced by inactivation of the Hippo pathway, was highly expressed in HCC. Using a systematic molecular and genomic approach, we identified the Hippo-YAP1-SOX4 pathway as the mechanism through which YAP1 induces CD24 upregulation in HCC cells. CD24 knockdown significantly attenuated YAP1 activation-induced HCC. These findings shed light on the link between CD24 and HCC progression, particularly in the Hippo-inactivated subclass of HCC. Therefore, CD24 may serve as a potential target for specific treatment of this HCC subclass.

METTL3/16-mediated m6A modification of ZNNT1 promotes hepatocellular carcinoma progression by activating ZNNT1/osteopontin/S100A9 positive feedback loop-mediated crosstalk between macrophages and tumour cells.

Macrophages are the major components of tumour microenvironment, which play critical roles in tumour development. N6-methyladenosine (m6A) also contributes to tumour progression. However, the potential roles of m6A in modulating macrophages in hepatocellular carcinoma (HCC) are poorly understood. Here, we identified ZNNT1 as an HCC-related m6A modification target, which was upregulated and associated with poor prognosis of HCC. METTL3 and METTL16-mediated m6A modification contributed to ZNNT1 upregulation through stabilizing ZNNT1 transcript. ZNNT1 exerted oncogenic roles in HCC. Furthermore, ZNNT1 recruited and induced M2 polarization of macrophages via up-regulating osteopontin (OPN) expression and secretion. M2 Macrophages-recruited by ZNNT1-overexpressed HCC cells secreted S100A9, which further upregulated ZNNT1 expression in HCC cells via AGER/NF-κB signaling. Thus, this study demonstrates that m6A modification activated the ZNNT1/OPN/S100A9 positive feedback loop, which promoted macrophages recruitment and M2 polarization, and enhanced malignant features of HCC cells. m6A modification-triggered ZNNT1/OPN/S100A9 feedback loop represents potential therapeutic target for HCC.

Progress in the treatment of diabetic cardiomyopathy, a systematic review.

Diabetic cardiomyopathy (DCM) is a condition characterized by myocardial dysfunction that occurs in individuals with diabetes, in the absence of coronary artery disease, valve disease, and other conventional cardiovascular risk factors such as hypertension and dyslipidemia. It is considered a significant and consequential complication of diabetes in the field of cardiovascular medicine. The primary pathological manifestations include myocardial hypertrophy, myocardial fibrosis, and impaired ventricular function, which can lead to widespread myocardial necrosis. Ultimately, this can progress to the development of heart failure, arrhythmias, and cardiogenic shock, with severe cases even resulting in sudden cardiac death. Despite several decades of both fundamental and clinical research conducted globally, there are currently no specific targeted therapies available for DCM in clinical practice, and the incidence and mortality rates of heart failure remain persistently high. Thus, this article provides an overview of the current treatment modalities and novel techniques pertaining to DCM, aiming to offer valuable insights and support to researchers dedicated to investigating this complex condition.

The blockade of neuropeptide FF receptor 1 and 2 differentially contributed to the modulating effects on fentanyl-induced analgesia and hyperalgesia in mice.

Neuropeptide FF (NPFF) plays a critical role in various physiological processes through the activation of neuropeptide FF receptor 1 and 2 (NPFFR1 and NPFFR2). Numerous evidence has indicated that NPFF exhibits opposite opioid-modulating effects on opioid-induced analgesia after supraspinal and spinal administrations, while the detailed role of NPFFR1 and NPFFR2 remains unclear. In this study, we employed pharmacological and genetic inhibition of NPFFR to investigate the modulating roles of central NPFFR1 and NPFFR2 in opioid-induced analgesia and hyperalgesia, using a male mouse model of acute fentanyl-induced analgesia and secondary hyperalgesia. Our findings revealed that intrathecal (i.t.) injection of the nonselective NPFFR antagonist RF9 significantly enhanced fentanyl-induced analgesia, whereas intracerebroventricular (i.c.v.) injection did not show the same effect. Moreover, NPFFR2 deficient (npffr2-/-) mice exhibited stronger analgesic responses to fentanyl compared to wild type (WT) or NPFFR1 knockout (npffr1-/-) mice. Intrathecal injection of RF9 in npffr1-/- mice also significantly enhanced fentanyl-induced analgesia. These results indicate a crucial role of spinal NPFFR2 in the enhancement of opioid analgesia. Contrastingly, hyperalgesia induced by fentanyl was markedly reversed in npffr1-/- mice but remained unaffected in npffr2-/- mice. Similarly, i.c.v. injection of the selective NPFFR1 antagonist RF3286 effectively prevented fentanyl-induced hyperalgesia in WT or npffr2-/- mice. Notably, co-administration of i.c.v. RF3286 and i.t. RF9 augmented fentanyl-induced analgesia while reducing hyperalgesia. Collectively, these findings highlight the modulating effects of blocking spinal NPFFR2 and supraspinal NPFFR1 on fentanyl-induced analgesia and hyperalgesia, respectively, which shed a light on understanding the pharmacological function of NPFF system in future studies.

Peptide-Drug Conjugates: Design, Chemistry, and Drug Delivery System as a Novel Cancer Theranostic.

The emergence of peptide-drug conjugates (PDCs) that utilize target-oriented peptide moieties as carriers of cytotoxic payloads, interconnected with various cleavable/noncleavable linkers, resulted in the key-foundation of the new era of targeted therapeutics. They are capable of retaining the integrity of conjugates in the blood circulatory system as well as releasing the drugs at the tumor microenvironment. Other valuable advantages are specificity and selectivity toward targeted-receptors, higher penetration ability, and drug-loading capacity, making them a suitable candidate to play their vital role as promising carrier agents. In this review, we summarized the types of cell-targeting (CTPs) and cell-penetrating peptides (CPPs) that have broad applications in the advancement of targeted drug-delivery systems (DDS). Moreover, the techniques to overcome the limitations of peptide-chemistry for their extensive implementation to construct the PDCs. Besides this, the diversified breakthrough of linker chemistry, and ample knowledge of various cytotoxic payloads used in PDCs in recent years, as well as the mechanism of action of PDCs was critically discussed. The principal aim is to provide scattered and diversified knowledge in one place and to help researchers understand the pinching knots in the science of PDC development, also their progression toward a bright future for PDCs as novel theranostics in clinical practice.

The Potential Application of Aloe Barbadensis Mill. as Chinese Medicine for Constipation: Mini-Review.

Aloe barbadensis Mill. has a long history of medicinal use in the annals of traditional Chinese medicine, wherein it has garnered considerable renown. Its multifaceted therapeutic properties, characterized by its anti-inflammatory and antibacterial attributes, alongside its established efficacy as a laxative agent, have been extensively documented. This review commences with an exploration of the nomenclature, fundamental characteristics, and principal constituents of Aloe barbadensis Mill. responsible for its laxative effects. Subsequently, we delve into an extensive examination of the molecular mechanisms underlying Aloe barbadensis Mill.'s laxative properties, types of constipation treatments, commercially available preparations, considerations pertaining to toxicity, and its clinical applications. This review aims to serve as a comprehensive reference point for healthcare professionals and researchers, fostering an enhanced understanding of the optimal utilization of Aloe barbadensis Mill. in the treatment of constipation.

Case Report: Temporary pacing using active fixation lead and invasive electrophysiology studies for immune checkpoint inhibitor associated reversible advanced atrioventricular block.

A case of immune checkpoint inhibitors (ICIs)-associated myocarditis with reversible advanced atrioventricular block (AVB) was reported. We innovatively used active fixation lead connected to an external device for prolonged temporary pacing until atrioventricular conduction recovered. Invasive electrophysiology studies were performed to evaluate atrioventricular conduction in detail. Long-term follow-up for nearly 120-days and repeated long-term electrocardiography was conducted to ensure the conduction system was truly recovered.

Effects of alcohol on the composition and metabolism of the intestinal microbiota among people with HIV: a cross-sectional study.

OBJECTIVES: Alcohol consumption is not uncommon among people with HIV (PWH) and may exacerbate HIV-induced intestinal damage, and further lead to dysbiosis and increased intestinal permeability. This study aimed to determine the changes in the faecal microbiota and its association with alcohol consumption in HIV-infected patients. METHODS: A cross-sectional survey was conducted between November 2021 and May 2022, and 93 participants were recruited. To investigate the alterations of alcohol misuse on fecal microbiology in HIV-infected individuals, we performed 16s rDNA gene sequencing on fecal samples from the low to moderate drinking (n=21) and non-drinking (n=72) groups. RESULTS: Comparison between groups using alpha and beta diversity showed that the diversity of stool microbiota in the low to moderate drinkinge group did not differ from that of the non-drinking group (all P>0.05). The Linear discriminant Analysis effect size (LEfSe) algorithm was to determine the bacterial taxa associated with alcohol consumption, and the results showed altered fecal bacterial composition in HIV-infected patients who consumed alcohol, with Coprobacillus, Pseudobutyrivibrio and Peptostreptococcaceae enriched, and Pasteurellaceae and Xanthomonadaceae were depleted. In addition, by using the Kyoto Encyclopedia of Genes and Genomes (KEGG) functional microbiome features were also found to be altered in the low to moderate drinking group, showing a reduction in metabolic pathways (P=0.036) and cardiovascular disease pathway (P=0.006). CONCLUSION: Low to moderate drinking will change the composition, metabolism and cardiovascular disease pathway of the gut microbiota of HIV-infected patients.

Structure-Activity Relationships of a Novel Cyclic Hexapeptide That Exhibits Multifunctional Opioid Agonism and Produces Potent Antinociceptive Activity.

The cyclic peptide c[d-Lys2, Asp5]-DN-9 has recently been identified as a multifunctional opioid/neuropeptide FF receptor agonist, displaying potent analgesic activity with reduced side effects. This study utilized Tyr-c[d-Lys-Gly-Phe-Asp]-d-Pro-NH2 (0), a cyclic hexapeptide derived from the opioid pharmacophore of c[d-Lys2, Asp5]-DN-9, as a chemical template. We designed, synthesized, and characterized 22 analogs of 0 with a single amino acid substitution to investigate its structure-activity relationship. Most of these cyclic hexapeptide analogs exhibited multifunctional activity at µ and δ opioid receptors (MOR and DOR, respectively) and produced antinociceptive effects following subcutaneous administration. The lead compound analog 15 showed potent agonistic activities at the MOR, κ opioid receptor (KOR), and DOR in vitro and produced a strong and long-lasting analgesic effect through peripheral MOR and KOR in the tail-flick test. Further biological evaluation identified that analog 15 did not cause significant side effects such as tolerance, withdrawal, or reward liability.

All-Hydrocarbon Stapled Peptide Multifunctional Agonists at Opioid and Neuropeptide FF Receptors: Highly Potent, Long-Lasting Brain Permeant Analgesics with Diminished Side Effects.

Our previous study reported the multifunctional agonist for opioid and neuropeptide FF receptors DN-9, along with its cyclic peptide analogues c[D-Cys2, Cys5]-DN-9 and c[D-Lys2, Asp5]-DN-9. These analogues demonstrated potent antinociceptive effects with reduced opioid-related side effects. To develop more stable and effective analgesics, we designed, synthesized, and evaluated seven hydrocarbon-stapled cyclic peptides based on DN-9. In vitro calcium mobilization assays revealed that most of the stapled peptides, except 3, displayed multifunctional agonistic activities at opioid and neuropeptide FF receptors. Subcutaneous administration of all stapled peptides resulted in effective and long-lasting antinociceptive activities lasting up to 360 min. Among these stapled peptides, 1a and 1b emerged as the optimized compounds, producing potent central antinociception following subcutaneous, intracerebroventricular, and oral administrations. Additionally, subcutaneous administration of 1a and 1b caused nontolerance antinociception, with limited occurrence of constipation and addiction. Furthermore, 1a was selected as the final optimized compound due to its wider safety window compared to 1b.

Metabolomic profiles, polygenic risk scores and risk of rheumatoid arthritis: a population-based cohort study in the UK Biobank.

OBJECTIVE: To investigate the relationship between metabolomic profiles, genome-wide polygenic risk scores (PRSs) and risk of rheumatoid arthritis (RA). METHODS: 143 nuclear magnetic resonance-based plasma metabolic biomarkers were measured among 93 800 participants in the UK Biobank. The Cox regression model was used to assess the associations between these metabolic biomarkers and RA risk, and genetic correlation and Mendelian randomisation analyses were performed to reveal their causal relationships. Subsequently, a metabolic risk score (MRS) comprised of the weighted sum of 17 clinically validated metabolic markers was constructed. A PRS was derived by assigning weights to genetic variants that exhibited significant associations with RA at a genome-wide level. RESULTS: A total of 620 incident RA cases were recorded during a median follow-up time of 8.2 years. We determined that 30 metabolic biomarkers were potentially associated with RA, while no further significant causal associations were found. Individuals in the top decile of MRS had an increased risk of RA (HR 3.52, 95% CI: 2.80 to 4.43) compared with those below the median of MRS. Further, significant gradient associations between MRS and RA risk were observed across genetic risk strata. Specifically, compared with the low genetic risk and favourable MRS group, the risk of incident RA in the high genetic risk and unfavourable MRS group has almost elevated by fivefold (HR 6.10, 95% CI: 4.06 to 9.14). CONCLUSION: Our findings suggested the metabolic profiles comprising multiple metabolic biomarkers contribute to capturing an elevated risk of RA, and the integration of genome-wide PRSs further improved risk stratification.

Survival times of HIV/AIDS in different AIDS Diagnostic and Treatment Guidelines from 2006 to 2020 in Liuzhou, China.

BACKGROUND: To compare the survival rates of four timing of treatment initiation for people living with HIV/AIDS provided in China in 2006, 2011, 2015, and 2018, and to investigate the factors impacting survival time. METHODS: A people living with HIV/AIDS retrospective cohort study was in Liuzhou City from April 2006 to December 2020. The information was obtained from the National Comprehensive AIDS Prevention and Control Information System. Life tables and the Kaplan-Meier method were used to calculate participant survival rates and time. The univariate and multivariate Cox regression models were used to investigate the factors related to survival. RESULTS: 18,543 participants were included in this study. In four periods, the 1-year survival rates were 81%, 87%, 95%, and 95%. The 2-year survival rates were 76%, 85%, 93%, and 94%. The 3-year survival rates were 73%, 84%, 92%, and 94%. Results of multivariate Cox regression showed that sex, age of HIV diagnosis, ethnicity, household registration, occupation, marital status, the timing of treatment, education level, route of HIV transmission, whether receiving antiretroviral therapy (ART), and the count of CD4+T cells at baseline (count of CD4+T cells at HIV diagnosis) were factors that are significantly correlated with mortality caused by HIV infection. CONCLUSIONS: With the Guidelines updated from 2006 to 2020, the 1-, 2-, and 3-year survival rates of people living with HIV/AIDS in four periods tended to increase. The timing of treatment initiation of the updated edition of the AIDS Diagnostic and Treatment Guidelines (Guidelines) significantly prolonged the survival time of people living with HIV/AIDS.

Verifying AXL and putative proteins as SARS-CoV-2 receptors by DnaE intein-based rapid cell-cell fusion assay.

As the understanding of the mechanisms of SARS-CoV-2 infection continues to grow, researchers have come to realize that ACE2 and TMPRSS2 receptors are not the only way for the virus to invade the host, and that there are many molecules that may serve as potential receptors or cofactors. The functionality of these numerous receptors, proposed by different research groups, demands a fast, simple, and accurate validation method. To address this issue, we here established a DnaE intein-based cell-cell fusion system, a key result of our study, which enables rapid simulation of SARS-CoV-2 host cell infection. This system allowed us to validate that proteins such as AXL function as SARS-CoV-2 spike protein receptors and synergize with ACE2 for cell invasion, and that proteins like NRP1 act as cofactors, facilitating ACE2-mediated syncytium formation. Our results also suggest that mutations in the NTD of the SARS-CoV-2 Delta variant spike protein show a preferential selection for Spike-AXL interaction over Spike-LDLRAD3. In summary, our system serves as a crucial tool for the rapid and comprehensive verification of potential receptors, screening of SARS-CoV-2-neutralizing antibodies, or targeted drugs, bearing substantial implications for translational clinical applications.

Validation of E/e' Using the Index-Beat Method as an Estimate of Left Atrial Pressure in Patients with Atrial Fibrillation.

INTRODUCTION: Echocardiographic assessment of diastolic function during atrial fibrillation (AF) remains challenging due to the irregular cardiac cycle length. We sought to assess whether the index-beat method, the beat following two preceding cardiac cycles of equal duration, could provide a more reliable measurement of E/e' (mitral E wave/diastolic tissue Doppler velocity) than the conventional averaging of consecutive beats and hence facilitate the noninvasive estimation of elevated left atrial pressure (LAP) in patients with AF. METHODS: We prospectively studied 35 patients with persistent AF who had preserved left ventricular ejection fraction and underwent radiofrequency ablation. LAP was measured in conjunction with transseptal puncture during catheter ablation. Echocardiography was performed 24 h before ablation and E/e' was determined using the recommended averaging of 10 beats and the index-beat method, with the observers blinded to the clinical details and LAP measurements. RESULTS: Correlation analysis showed a strong positive correlation between two methods in terms of both septal E/e' (r = 0.841, p < 0.001) and lateral E/e' (r = 0.930, p < 0.001). Bland-Altman analysis also showed a good agreement between the two measurement methods in terms of E/e'. E/e' determined using both conventional averaging and the index-beat method was significantly correlated with LAP (p < 0.05). After Fisher Z transformation, we found that the index-beat septal E/e' had a better correlation with LAP than did the conventional averaging E/e' (r = 0.736 vs. r = 0.392, Zr = -2.110, p = 0.035). Furthermore, the index-beat method took significantly less time to measure E/e' (mean 33.6 s; 95% confidence intervals [CIs]: 32.1 s-36.2 s) than did conventional averaging method (mean 96.2 s; 95% CI: 90.2 s-102.3 s; p < 0.001). Receiver operating characteristic curve analysis revealed that the optimal cut-off for predicting mean LAP >12 mm Hg was 11 (sensitivity 100%; specificity 77.3%) for index-beat septal E/e' and 16 (sensitivity 61.5%; specificity 95.5%) for index-beat lateral E/e'. CONCLUSIONS: Good correlations were found between E/e' and LAP in patients with AF, particularly with the index-beat method. Moreover, the index-beat method can easily measure E/e' at an accuracy similar to that for the conventional averaging of consecutive beats, which can therefore be applied to assess the diastolic dysfunction and potentially improve the diagnosis of heart failure in patients with AF.

N6 -methyladenosine-modified FAM111A-DT promotes hepatocellular carcinoma growth via epigenetically activating FAM111A.

As an epitranscriptomic modulation manner, N6 -methyladenosine (m6 A) modification plays important roles in various diseases, including hepatocellular carcinoma (HCC). m6 A modification affects the fate of RNAs. The potential contributions of m6 A to the functions of RNA still need further investigation. In this study, we identified long noncoding RNA FAM111A-DT as an m6 A-modified RNA and confirmed three m6 A sites on FAM111A-DT. The m6 A modification level of FAM111A-DT was increased in HCC tissues and cell lines, and increased m6 A level was correlated with poor survival of HCC patients. m6 A modification increased the stability of FAM111A-DT transcript, whose expression level showed similar clinical relevance to that of the m6 A level of FAM111A-DT. Functional assays found that only m6 A-modified FAM111A-DT promoted HCC cellular proliferation, DNA replication, and HCC tumor growth. Mutation of m6 A sites on FAM111A-DT abolished the roles of FAM111A-DT. Mechanistic investigations found that m6 A-modified FAM111A-DT bound to FAM111A promoter and also interacted with m6 A reader YTHDC1, which further bound and recruited histone demethylase KDM3B to FAM111A promoter, leading to the reduction of the repressive histone mark H3K9me2 and transcriptional activation of FAM111A. The expression of FAM111A was positively correlated with the m6 A level of FAM111A-DT, and the expression of methyltransferase complex, YTHDC1, and KDM3B in HCC tissues. Depletion of FAM111A largely attenuated the roles of m6 A-modified FAM111A-DT in HCC. In summary, the m6 A-modified FAM111A-DT/YTHDC1/KDM3B/FAM111A regulatory axis promoted HCC growth and represented a candidate therapeutic target for HCC.

Identification of a pH-Responsive Peptide-Paclitaxel Conjugate as a Novel Drug with Improved Therapeutic Potential.

A highly sensitive, nontoxic, hydrophilic cell-penetrating peptide (CPP = c[RGDKLAK]) was selected for the construction of an effective peptide-drug conjugate (PDC). A hydrophobic drug paclitaxel (PTX) was successfully conjugated with CPP via ester linkage with succinic acid (SA) as a pH-cleavable linker moiety. The characterization techniques employed in this study indicate the >95% purity of the resulting PDC (CPP-SA-PTX). The in vitro studies show that our proposed PDC exhibits enhanced stability (∼90%) and cytotoxicity (EC50 = 8.32 ± 0.09 nM). Besides the excellent solubility of PDC in water, the PTX effect on positive ß-tubulin-III indicates that the drug releases retained pharmacological properties. Additionally, in vivo, therapeutic-dose treatment reveals the prominent tumor-growth inhibitory effects (2.82-3.24-fold) of PDC in tumor mice models. Subsequently, these observations confirmed that our novel-designed PDC (CPP-SA-PTX) adduct may serve as a promising therapeutic agent to treat glioblastoma.

Three-dimensional High-Resolution Dark-Blood Late Gadolinium Enhancement Imaging for Improved Atrial Scar Evaluation.

Background Radiofrequency ablation (RFA) is a widely used treatment for atrial fibrillation, reducing the risk of cardiac arrhythmia. Detailed visualization and quantification of atrial scarring has the potential to improve preprocedural decision-making and postprocedural prognosis. Conventional bright-blood late gadolinium enhancement (LGE) MRI can help detect atrial scars; however, its suboptimal myocardium to blood contrast inhibits accurate scar estimation. Purpose To develop and test a free-breathing LGE cardiac MRI approach that simultaneously provides high-spatial-resolution dark-blood and bright-blood images for improved atrial scar detection and quantification. Materials and Methods A free-breathing, independent navigator-gated, dark-blood phase-sensitive inversion recovery (PSIR) sequence with whole-heart coverage was developed. Two coregistered high-spatial-resolution (1.25 × 1.25 × 3 mm3) three-dimensional (3D) volumes were acquired in an interleaved manner. The first volume combined inversion recovery and T2 preparation to achieve dark-blood imaging. The second volume functioned as the reference for phase-sensitive reconstruction with built-in T2 preparation for improved bright-blood contrast. The proposed sequence was tested in prospectively enrolled participants who had undergone RFA for atrial fibrillation (mean time since RFA, 89 days ± 26 [SD]) from October 2019 to October 2021. Image contrast was compared with conventional 3D bright-blood PSIR images using the relative signal intensity difference. Furthermore, native scar area quantification obtained from both imaging approaches was compared with measurements obtained with electroanatomic mapping (EAM) as the reference standard. Results A total of 20 participants (mean age, 62 years ± 9; 16 male) who underwent RFA for atrial fibrillation were included. The proposed PSIR sequence successfully acquired 3D high-spatial-resolution volumes in all participants, with a mean scan time of 8.3 minutes ± 2.4. The developed PSIR sequence improved scar to blood contrast compared with conventional PSIR sequence (mean contrast, 0.60 arbitrary units [au] ± 0.18 vs 0.20 au ± 0.19, respectively; P < .01) and correlated with EAM regarding scar area quantification (r = 0.66 [P < .01] vs r = 0.13 [P = .63]). Conclusion In participants who had undergone RFA for atrial fibrillation, an independent navigator-gated dark-blood PSIR sequence produced high-spatial-resolution dark-blood and bright-blood images with improved image contrast and native scar quantification compared with conventional bright-blood images. © RSNA, 2023 Supplemental material is available for this article.

Mitochondrial supercomplex assembly regulates metabolic features and glutamine dependency in mammalian cells.

Rationale: Mitochondria generate ATP via the oxidative phosphorylation system, which mainly comprises five respiratory complexes found in the inner mitochondrial membrane. A high-order assembly of respiratory complexes is called a supercomplex. COX7A2L is a supercomplex assembly factor that has been well-investigated for studying supercomplex function and assembly. To date, the effects of mitochondrial supercomplexes on cell metabolism have not been elucidated. Methods: We depleted COX7A2L or Cox7a2l in human and mouse cells to generate cell models lacking mitochondrial supercomplexes as well as in DBA/2J mice as animal models. We tested the effect of impaired supercomplex assembly on cell proliferation with different nutrient supply. We profiled the metabolic features in COX7A2L-/- cells and Cox7a2l-/- mice via the combined use of targeted and untargeted metabolic profiling and metabolic flux analysis. We further tested the role of mitochondrial supercomplexes in pancreatic ductal adenocarcinoma (PDAC) through PDAC cell lines and a nude mouse model. Results: Impairing mitochondrial supercomplex assembly by depleting COX7A2L in human cells reprogrammed metabolic pathways toward anabolism and increased glutamine metabolism, cell proliferation and antioxidative defense. Similarly, knockout of Cox7a2l in DBA/2J mice promoted the use of proteins/amino acids as oxidative carbon sources. Mechanistically, impaired supercomplex assembly increased electron flux from CII to CIII/CIV and promoted CII-dependent respiration in COX7A2L-/- cells which further upregulated glutaminolysis and glutamine oxidation to accelerate the reactions of the tricarboxylic acid cycle. Moreover, the proliferation of PDAC cells lacking COX7A2L was inhibited by glutamine deprivation. Conclusion: Our results reveal the regulatory role of mitochondrial supercomplexes in glutaminolysis which may fine-tune the fate of cells with different nutrient availability.

Synergistic interaction between DAMGO-NH2 and NOP01 in peripherally acting antinociception in two mouse models of formalin pain.

The most commonly used opioid analgesics are limited by their severe side-effects in the clinical treatment of pain. Preliminary reports indicate that the combination of classical opioids and N/OFQ receptor (NOP) ligands may be an effective strategy to reduce unwanted side-effects and improve antinociception. But the interaction of these two receptor ligands in pain regulation at the peripheral level remains unclear. In this study, the antinociception of a designed amide analogue of the mu opioid receptor (MOP) peptide agonist DAMGO, DAMGO-NH2, and its antinociceptive interaction with the peripherally limited NOP peptide agonist NOP01 was investigated in two mouse models of formalin pain. Our results showed that DAMGO-NH2 acted as a MOP agonist in in vitro functional assays. Moreover, local subcutaneous or intraplantar injection of DAMGO-NH2 exerted dose-related antinociception in both phases of the formalin orofacial and intraplantar pain, which could be mediated by the classical opioid receptor. Peripheral but not central pretreatment with the peripherally restricted opioid antagonist naloxone methiodide inhibited local DAMGO-NH2-induced antinociception, supporting the involvement of the peripheral opioid receptor in local DAMGO-NH2-induced antinociception. Furthermore, co-administration of the inactive doses of DAMGO-NH2 and NOP01 produced effective antinociception. More importantly, isobolographic analysis indicates that the combination of DAMGO-NH2 and NOP01 elicited supra-additive antinociception in these two models of formalin pain. In addition, the combination of DAMGO-NH2 and NOP01 did not change motor function of mice in rotarod test. In conclusion, these data suggest that peripheral DAMGO-NH2 and particularly its combination therapy with NOP01 may be effective for pain management.