Critical new insights into the interactions of hexafluoropropylene oxide-dimer acid (GenX or HFPO-DA) with albumin at molecular and cellular levels.

A key characteristic to be elucidated, to address the harmful health risks of environmental perfluorinated alkyl substances (PFAS), is their binding modes to serum albumin, the most abundant protein in blood. Hexafluoropropylene oxide-dimer acid (GenX or HFPO-DA) is a new industrial replacement for the widespread linear long-chain PFAS. However, the detailed interaction of new-generation short-chain PFAS with albumin is still lacking. Herein, the binding characteristics of bovine serum albumin (BSA) to GenX were explored at the molecular and cellular levels. It was found that this branched short-chain GenX could bind to BSA with affinity lower than that of legacy linear long-chain perfluorooctanoic acid (PFOA). Site marker competitive study and molecular docking simulation revealed that GenX interacted with subdomain IIIA to form BSA-GenX complex. Consistent with its weaker affinity to albumin protein, the cytotoxicity of branched short-chain GenX was less susceptible to BSA binding compared with that of the linear long-chain PFOA. In contrast to the significant effects of strong BSA-PFOA interaction, the weak affinity of BSA-GenX binding did not influence the structure of protein and the cytotoxicity of GenX. The detailed characterization and direct comparisons of serum albumin interaction with new generation short-chain GenX will provide a better understanding for the toxicological properties of this new alternative.

Comparison of monte carlo tally techniques for dosimetry in a transmission-type X-ray tube.

This study discussed comparing result accuracy and time cost under different tally methods using MCNP6 for a novel transmission X-ray tube which was designed for the Auger electron yield with specific material (eg. iodine). The assessment included photon spectrum, percent depth dose, mass-energy absorption coefficient corresponding to air and water, and figure of merit comparison. The mean energy of in-air phantom was from 41.8 keV (0 mm) to 40.9 keV (100 mm), and the mean energy of in-water phantom was from 41.41 keV (0 mm) to 45.2 keV (100 mm). The specific dose conversion factors based mass-energy absorption coefficient corresponding to different materials was established and the difference was less than 2% for the dose conversion of FMESH comparing to measurement data. FMESH had better figure of merit (FOM) than the F6 tally for the dose parameter assessment, which mean the dose calculation that focused on the superficial region could be assessed with more calculation efficiency by FMESH tally for this novel transmission X-ray tube. The results of this study could help develop treatment planning system (TPS) to quickly obtain the calculated data for phase space data establishment and heterogeneous correction under different physical condition settings. .

Interacting trends of colorectal cancer incidence: the combined effects of screening and birth cohort.

BACKGROUND: Colorectal cancer remains a major global public health challenge. Its incidence is shaped by a complex interplay of screening programmes and age, period and cohort factors. METHODS: We introduce a novel Age-Period-Cohort-Screening (APCS) model to analyse trends in colorectal cancer incidence in Taiwan from 2000 to 2019. RESULTS: In 2010, the incidence of colorectal cancer in Taiwan increased by 19.2% (95% CI: 13.5%, 25.3%) for men and 15.6% (95% CI: 9.2%, 22.4%) for women. This was followed by annual declines of 3.4% (95% CI: 2.8%, 4.1%) and 3.1% (95% CI: 2.4%, 3.9%), respectively. By 2015 for men and 2014 for women, the age-standardized incidence had fallen below the levels projected in a no-screening scenario. By 2019, the incidence had further declined by 12.4% (95% CI: 11.8%, 13.1%) for men and 11.6% (95% CI: 10.7%, 12.6%) for women, compared with the no-screening scenario. Cohort effects have shown a persistent rise from 1920 to 1980: incidence increased 5.8-fold for men and 3.1-fold for women. The trend began to plateau after 1980, with a noticeable decline in women. CONCLUSION: Through its screening programme, Taiwan has successfully reduced colorectal cancer incidence by 10% as of 2019. Furthermore, the incidence due to cohort effects has plateaued and even begun to decline. However, continued monitoring remains crucial. The advanced APCS model could serve as a robust analytical tool for other researchers and policy makers evaluating the impacts of cancer screening programmes on incidence trends.

RG108 attenuates acute kidney injury by inhibiting P38 MAPK/FOS and JNK/JUN pathways.

Acute kidney injury (AKI) is an important clinical syndrome characterised by a sudden decline in renal function, often accompanied by renal inflammation and tubular epithelial cell damage. It has been reported that inhibiting DNA methylation significantly suppress the progression of AKI. In the current study, we investigate the effect of the DNA methyltransferase (DNMT) inhibitor RG108 in cisplatin- and hypoxia-reoxygenation-induced AKI. The expression of kidney injury molecules and inflammatory factors was examined by immunofluorescence, Western blotting and Real-time PCR. The results demonstrated that RG108 treatment significantly reduced kidney inflammation and injury. Furthermore, RNA-seq analysis was performed to reveal the regulatory mechanism of RG108 in AKI. The expression of the FOS and JUN genes, which are downstream of the MAPK pathway, were significant increased in AKI. Meanwhile, the expression of FOS and JUN were both inhibited by RG108, which is similar to what we found treatment with a specific JNK inhibitor and a specific p38 MAPK inhibitor, and thus attenuated renal inflammation and injury. In conclusion, we suggest that RG108 inhibits P38 MAPK/FOS and JNK/JUN pathways and attenuates renal injury and inflammatory responses. In these results, RG108 may become a novel MAPK pathway inhibitor and a clinical candidate for the treatment of AKI.

Path planning optimization for swine manure-cleaning robots through enhanced slime mold algorithm with cellular automata.

One of the primary challenges for robotic manure cleaners in pig farming is to plan the shortest path to designated cleaning points under specified conditions with minimal processing cost and time, while avoiding collisions. However, pigs are randomly distributed in actual pig farms, which obstructs the robots' movement and complicates the rapid determination of optimal solutions. To address these issues, this study introduces the concept of interaction among cellular automaton cell neighborhoods and proposes the Cellular Automata Slime Mold Algorithm (CASMA). This enhanced slime mold algorithm accelerates convergence speed and improves search accuracy. To validate its effectiveness, CASMA was compared with four metaheuristic algorithms (ACO, FA, PSO, and WPA) through performance tests and simulated experiments. Results demonstrate that in complex pigsty environments with varying numbers of pigs, CASMA reduces average step consumption by 8.03%, 1.61%, 0.99%, and 4.26% compared with these algorithms and saves processing time by averages of 13.20%, 20.11%, 10.86%, and 6.4%, respectively. In addition, in dynamic obstacle experiments, CASMA achieved average time savings of 48.27% and 56.28% compared with A* and TS, respectively, while reducing step consumption. Overall, CASMA enhances the efficiency of manure-cleaning robots in pig farms, thereby improving animal welfare.

Research Progress and Emerging Directions in Stimulus Electro-Responsive Polymer Materials.

Stimulus electro-responsive polymer materials can reversibly change their physical or chemical properties under various external stimuli such as temperature, light, force, humidity, pH, and magnetic fields. This review introduces typical conventional stimulus electro-responsive polymer materials and extensively explores novel directions in the field, including multi-stimuli electro-responsive polymer materials and humidity electro-responsive polymer materials pioneered by our research group. Despite significant advancements in stimulus electro-responsive polymer materials, ongoing research focuses on enhancing their efficiency, lifespan, and production costs. Interdisciplinary collaboration and advanced technologies promise to broaden the application scope of these materials, particularly in medical and environmental protection fields, ultimately benefiting society.

New Antifungal and Antifeedant Metabolites from Daldinia eschscholtzii Cocultured with Colletotrichum pseudomajus.

The synchronous co-culture of Daldinia eschscholtzii and Colletotrichum pseudomajus produced one new linear polyketide, eschscholin C (1), along with three known compounds (2-4). One new acorane sesquiterpene, coldaldrin A (5), and one new amide derivative, coldaldamide A (6) as the probe for polyketide intermediate capture, and three known compounds (7-9) were isolated from the sequential co-culture of D. eschscholtzii with C. pseudomajus. The structures and absolute configurations of 1, 5 and 6 were established by spectroscopic analysis including 1D, 2D NMR, the calculations of the NMR, and ECD data. Most compounds showed significant antifungal activities against the tea pathogens C. pseudomajus, and Fusarium asiaticum with MICs of 2-8 µg/mL. Compound 4 also showed antifeedant activity against silkworms with feeding deterrence indices of 79% at the concentration of 50 µg/cm2.

Association of antipsychotic formulations with sudden cardiac death in patients with schizophrenia: A nationwide population-based case-control study.

The aim of this study was to clarify the association between various antipsychotic formulations-oral-daily antipsychotics (OAPs), long-acting injectable antipsychotics (LAIs), and their combination-and the risk of sudden cardiac death (SCD). We conducted a nationwide population-based case-control study using data from 2011 to 2020 from the National Health Insurance Research Database and multiple-cause-of-death data from Taiwan. The study included patients with a new diagnosis of schizophrenia who were followed for SCD occurrence until 2020. Cases and controls were frequency-matched at a 1:4 ratio by age, sex, and year of new schizophrenia diagnosis. Compared with the use of OAP monotherapy, the use of LAI and OAP combination (OR = 1.91) and LAI monotherapy (OR = 1.45) were associated with an increased risk of SCD. Additionally, cardiovascular comorbidities (adjusted OR = 11.15) were identified as a significant risk factor for SCD. This study revealed the following hierarchy of SCD risk associated with antipsychotic formulations (listed from lowest to highest risk): nonuse of antipsychotics, OAP monotherapy, LAI monotherapy, and their combination. These findings underscore the importance of assessing cardiovascular disease history before LAIs are prescribed to patients with schizophrenia and indicate that physicians should avoid prescribing combined antipsychotics when using LAIs.

Pichia pastoris composition expressed aerolysin mutant of Aeromonas veronii as an oral vaccine evaluated in zebrafish (Danio rerio).

Vaccines are one of the most practical means to stop the spreading of Aeromonas veronii in aquaculture. In this study, virulence factor aerolysin mutant NTaer which has lost its hemolytic activity was used as a target antigen. Pichia pastoris constitutive secretory expression NTaer (GS115-NTaer) was used as a potential safe oral vaccine to evaluate its effectiveness on zebrafish immunity. The result shows that vaccination of GS115- NTaer for four weeks did not affect the growth performance of the host, while eliciting an effective immune protective response. Compared with the control group, the GS115-NTaer could significantly up-regulate the relative expression level of the intestinal tight junction protein 1α (TJP1α) gene, and significantly increased the contents of lysozyme (LYZ), complement C3 and C4 in the gut, indicating that the innate immune response of the fish was activated. The relative gene expression levels of macrophage-expressed gene 1 (MPEG1) and T cell receptor (TCR-α) in the gut, and MPEG1, CD4, CD8, TCR-α, GATA3, and T-bet in the spleen were all increased significantly, indicating that the cellular immune response of the fish was activated. Furthermore, the contents of serum IgM and intestinal mucosa IgZ antibodies were significantly increased, which showed that humoral immunity was also activated. Moreover, inoculation with GS115-NTaer significantly changed the structure of gut microbiota. In particular, the relative ratio of (Firmicutes + Fusobacteriota + Bacteroidota)/Proteobacteria was significantly higher than that of the control and GS115 groups. Lastly, the vaccinated fish were challenged with A. veronii, and the relative percent survival of GS115 and the GS115-NTear groups was 14.28% and 33.43%. This improvement of immunity was not only due to the specific immune response but also attributed to the improvement of innate immunity and the gut microbiota which was demonstrated by the germ-free zebrafish model. Collectively, this study provides information on the effectiveness of GS115-NTear as an oral vaccine for the green prevention and control of A. veronii infection in fish aquaculture.

Glucose fluctuations aggravate cardiomyocyte apoptosis by enhancing the interaction between Txnip and Akt.

BACKGROUND: Glucose fluctuations may be involved in the pathophysiological process of cardiomyocyte apoptosis, but the exact mechanism remains elusive. This study focused on exploring the mechanisms related to glucose fluctuation-induced cardiomyocyte apoptosis. METHODS: Diabetic rats established via an injection of streptozotocin were randomized to five groups: the controlled diabetic (CD) group, the uncontrolled diabetic (UD) group, the glucose fluctuated diabetic (GFD) group, the GFD group rats with the injection of 0.9% sodium chloride (NaCl) (GFD + NaCl) and the GFD group rats with the injection of N-acetyl-L-cysteine (NAC) (GFD + NAC). Twelve weeks later, cardiac function and apoptosis related protein expressions were tested. Proteomic analysis was performed to further analyze the differential protein expression pattern of CD and GFD. RESULTS: The left ventricular ejection fraction levels and fractional shortening levels were decreased in the GFD group, compared with those in the CD and UD groups. Positive cells tested by DAB-TUNEL were increased in the GFD group, compared with those in the CD group. The expression of Bcl-2 was decreased, but the expressions of Bax, cleaved caspase-3 and cleaved caspase-9 were increased in response to glucose fluctuations. Compared with CD, there were 527 upregulated and 152 downregulated proteins in GFD group. Txnip was one of the differentially expressed proteins related to oxidative stress response. The Txnip expression was increased in the GFD group, while the Akt phosphorylation level was decreased. The interaction between Txnip and Akt was enhanced when blood glucose fluctuated. Moreover, the application of NAC partially reversed glucose fluctuations-induced cardiomyocyte apoptosis. CONCLUSIONS: Glucose fluctuations lead to cardiomyocyte apoptosis by up-regulating Txnip expression and enhancing Txnip-Akt interaction.

The Antiphytopathogenic Metabolites and the Synergy of Endophytes Paraphaeosphaeria sp., Nigrospora oryzae from the Same Ginkgo biloba Host.

Two endophytes from the same Ginkgo biloba host were isolated and cultured separately. Three new eremophilane sesquiterpenoids (1-3), three new furan derivates (6, 8-9), one new polyketide (10), and four known compounds (4, 5, 7, 11) from Paraphaeosphaeria sp. and two new 10-membered macrolides (12-13), a new liner polyketide (14), a new benzofuran (15), and six known compounds (16-21) from Nigrospora oryzae were isolated. The structures of the isolated compounds were determined by spectroscopic methods, NMR calculations, and ECD calculations. The compounds 3-7, 9-10, 12, and 14-17 showed significant antiphytopathogenic effects against mycotoxigenic Alternaria sp. comparable to the activity of nystatin (positive control). Compounds 2, 6, 8, 9, and 18 indicated inhibitions against phytopathogen Fusarium asiaticum with MICs < 10 µg/mL. In addition, the compounds with weak antifungal activities from two endophytes were mixed to test their antifungal activity. The results showed that the metabolites from two endophytes had synergistic antifungal effects, and the beneficial interactions between natural products can induce more antifungal effects against plant pathogens than that of single compounds.

Baicalein ameliorates chronic itch in ACD mice by suppressing the spinal astrocytic STAT3-LCN2 cascade.

Chronic itch is a maladaptive and debilitating symptom in patients with allergic contact dermatitis (ACD), adversely affecting their quality of life. There is a lack of effective treatments for ACD-associated uncontrollable itch. In this study, we explored the antipruritic effects of baicalein (BE), a bioactive flavonoid extracted from the root of Scutellaria baicalensis Georgi, and the underlying mechanisms in alleviating chronic itch triggered by diphenylcyclopropenone (DCP) in a mouse model of ACD. The ACD mice were intraperitoneally injected with BE (5, 30, and 60 mg·kg-1·d-1) for 7 days during the DCP challenge phase. The results showed that DCP-treated mice exhibited severe spontaneous scratching behaviors that was reduced after BE injections in a dose-dependent manner accompanied by inhibition of spinal astrocyte activation. We observed that the spinal astrocytic STAT3-LCN2 cascade plays a crucial role in controlling the activation of astrocytes in chronic itch. Intrathecal injection of the STAT3 inhibitor AG490 or Lcn2 siRNA significantly reduced scratching behavior and astrocyte activation in ACD mice. Moreover, BE markedly attenuated the increased phosphorylation of STAT3 (p-STAT3) and LCN2 expression in the spinal cords of ACD mice and in lipopolysaccharide-stimulated primary spinal astrocytes. Altogether, BE relieved chronic itch by suppressing the spinal astrocytic STAT3-LCN2 cascade. These findings provide a potential avenue for the management of chronic itch. Schematic summary of the main findings illustrating that BE alleviates chronic itch through suppressing the spinal astrocytic STAT3-LCN2 cascade. Specifically, BE suppresses the expression of p-STAT3 to inhibit the reactive state of astrocytes in spinal dorsal horn, and then decreases the expression of astrocytic LCN2 to alleviate chronic itch in ACD mice.

Genetic complexity of killer-cell immunoglobulin-like receptor genes in human pangenome assemblies.

The killer-cell immunoglobulin-like receptor (KIR) gene complex, a highly polymorphic region of the human genome that encodes proteins involved in immune responses, poses strong challenges in genotyping owing to its remarkable genetic diversity and structural intricacy. Accurate analysis of KIR alleles, including their structural variations, is crucial for understanding their roles in various immune responses. Leveraging the high-quality genome assemblies from the Human Pangenome Reference Consortium (HPRC), we present a novel bioinformatic tool, the structural KIR annoTator (SKIRT), to investigate gene diversity and facilitate precise KIR allele analysis. In 47 HPRC-phased assemblies, SKIRT identifies a recurrent novel KIR2DS4/3DL1 fusion gene in the paternal haplotype of HG02630 and maternal haplotype of NA19240. Additionally, SKIRT accurately identifies eight structural variants and 15 novel nonsynonymous alleles, all of which are independently validated using short-read data or quantitative polymerase chain reaction. Our study has discovered a total of 570 novel alleles, among which eight haplotypes harbor at least one KIR gene duplication, six haplotypes have lost at least one framework gene, and 75 out of 94 haplotypes (79.8%) carry at least five novel alleles, thus confirming KIR genetic diversity. These findings are pivotal in providing insights into KIR gene diversity and serve as a solid foundation for understanding the functional consequences of KIR structural variations. High-resolution genome assemblies offer unprecedented opportunities to explore polymorphic regions that are challenging to investigate using short-read sequencing methods. The SKIRT pipeline emerges as a highly efficient tool, enabling the comprehensive detection of the complete spectrum of KIR alleles within human genome assemblies.

Using microfluidic and conventional platforms to evaluate the effects of lanthanides on spheroid formation.

Metastasis contributes to the increased mortality rate of cancer, but the intricate mechanisms remain unclear. Cancer cells from a primary tumor invade nearby tissues and access the lymphatic or circulatory system. If these cells manage to survive and extravasate from the vasculature into distant tissues and ultimately adapt to survive, they will proliferate and facilitate malignant tumor formation. Traditional two-dimensional (2D) cell cultures offer a rapid and convenient method for validating the efficacy of anticancer drugs within a reasonable cost range, but their utility is limited because of tumors' high heterogeneity in vivo and spatial complexities. Three-dimensional (3D) cell cultures that mimic the physiological conditions of cancer cells in vivo have gained considerable interest. In these cultures, cells assemble into spheroids through gravity, magnetic forces, or their low-adhesion to the plates. Although these approaches address some of the limitations of 2D cultures, they often require a considerable amount of time and cost. Therefore, this study aims to enhance the effectiveness of 3D culture techniques by using microfluidic systems to provide a high-throughput and sensitive pipeline for drug screening. Using these systems, we studied the effects of lanthanide elements, which have garnered interest in cancer treatment, on spheroid formation and cell spreading. Our findings suggest that these elements alter the compactness of cell spheroids and decrease cell mobility.

Differential Pharmacodynamic Effects on Psoriatic Biomarkers by Guselkumab Versus Secukinumab Correlate with Long-Term Efficacy: An ECLIPSE Substudy.

IL-23 is a cytokine produced by myeloid cells that drives the T helper 17 pathway and plays an essential role in the pathophysiology of plaque psoriasis. IL-23 activation initiates a cascade of cytokines subsequently inducing the expression of many psoriasis-related proteins. This study aimed to better understand the underlying mechanisms driving the differences between IL-23 and IL-17A blockade in patients with psoriasis and their implications for durability of clinical responses. Serum and/or skin biopsies were isolated from patients treated with guselkumab or secukinumab for evaluation of potential biomarkers of pharmacodynamic response to treatment. Guselkumab treatment led to significantly greater reductions of IL-17F and IL-22 serum levels than treatment with secukinumab at weeks 24 and 48, demonstrating sustained regulation of the IL-23/T helper 17 pathway. Analyses of proteomic and transcriptomic profiles of patient sera and skin biopsies demonstrated differential regulation of proteins involved in chemokine, TNF, and relevant immune signaling pathways to a greater degree with guselkumab than with secukinumab treatment. These data provide insights into the differences between the mechanisms and impact of IL-23 and IL-17A blockade in psoriasis, with implications for efficacy observations and treatment paradigms. Trial Registration: The original study was registered at ClinicalTrials.gov (NCT03090100).

A class of geranylquinol-derived polycyclic meroterpenoids from Arnebia euchroma against heart failure by reducing excessive autophagy and apoptosis in cardiomyocytes.

Ten new B-ring aromatized 6/6/6-tricyclic dearomatized benzocogeijerene-based meroterpenoids with unusual methyl 1,2-shift or demethylation (2-9b), and two new geranylquinol derivatives (1 and 10), together with two known compounds (11 and 12), were isolated from the roots of Arnebia euchroma. Their structures were elucidated by extensive spectroscopic methods, X-ray diffraction crystallography, and ECD calculations. The plausible biosynthetic pathways including the unusual methyl 1,2-shfit and demethylation for B-ring aromatized 6/6/6-tricyclic meroterpenoids were discussed. Compounds 1, 2, 5, 6, 11, and 12 showed significant cardioprotective activities comparable to diltiazem against isoprenaline (ISO)-induced H9C2 cell damage in vitro. Compound 11 probably exerted heart-protective effect on ISO-induced H9C2 cells by modulating the PI3K-AKT-mTOR pathway, reducing excessive autophagy, and decreasing myocardial apoptosis.

Exploring the relationship between depressive symptoms, problematic smartphone use, and cumulative risk factors in nursing students: A cross sectional study.

BACKGROUND: No single risk factor is decisive in shaping an individual's healthy development. This study aimed to analyze the relationship between depressive symptoms and a cumulative risk index comprising individual, family, and social variables among nursing students. METHODS: We enrolled 1716 Chinese nursing students from three universities in a paperless survey that assessed a range of individual, family, and social risk factors associated with depressive symptoms. Multiple risk analysis was conducted to create a composite risk score for each individual. A test for trend was employed to assess the relationship between the multiple risk classification and depressive symptoms individually. Additionally, a 2-step cluster analysis and χ2 tests were used to examine the relationship between the different clusters and the level of depressive symptoms. RESULTS: The mean scores of depressive symptoms increased significantly as the number of risk factors increased, regardless of their combination. As the number of risk factors increased, the proportion of nursing students in the normal group decreased, while the proportion in the group with depressive symptoms of varying severity tended to increase (P < 0.001). A high-risk cluster characterized by poor sleep quality combined with problematic smartphone use was associated with higher levels of depressive symptoms (P < 0.001). CONCLUSION: Based on these findings that cumulative exposure to multiple risk factors is more harmful than cumulative exposure to fewer risk factors, then interventions that isolate only one risk factor are less likely to be effective than those that are multifaceted.

MicroRNA 29a alleviates mitochondrial stress in diet-induced NAFLD by inhibiting the MAVS pathway.

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder characterized by fat accumulation in the liver. This leads to aggravated hepatocyte inflammation due to impaired mitochondrial function, mitochondrial double-stranded RNA (mt-dsRNA) release, elevated oxidative stress, and reactive oxygen species (ROS) production. MicroRNA-29a (miR-29a) is used to reduce hepatic fibrosis in cases of cholestatic liver damage and lessen the severity of non-alcoholic steatohepatitis in animal studies by influencing mitochondrial protein balance. However, the effectiveness of miR-29a in diminishing mt-dsRNA-induced exacerbation of NAFLD remains poorly understood, particularly in the context of a Western diet (WD). Our results have found that mice with increased miR-29a levels and fed a WD showed notably decreased serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), total cholesterol, and low-density lipoprotein cholesterol levels. They also experienced less weight gain and lower final body and liver weights. In addition, overexpression of miR-29a reduced the severity of fibrosis, alleviated hepatic oxidative stress, misfolded protein aggregates, and the release of mt-dsRNA. Moreover, miR-29a attenuated the innate immune mitochondrial antiviral-signaling protein (MAVS) pathway response. In vitro, the research using HepG2 cells confirmed that miR-29a reduces MAVS expression and decreases the release of mt-dsRNA and superoxide initiated by palmitic acid (PA). Analysis of luciferase activity further established that the specific binding of miR-29a to the 3'UTR of MAVS led to a repression of its expression. In conclusion, these groundbreaking findings underscore the potential of miR-29a in improving the treatment of NAFLD and liver steatofibrosis by inhibiting the MAVS signaling pathway.

Catalytic divergence of O-methyltransferases shapes the chemo-diversity of polymethoxylated bibenzyls in Dendrobium catenatum.

Erianin, crepidatin, and chrysotobibenzyl are typical medicinal polymethoxylated bibenzyls (PMBs) that are commercially produced in Dendrobium species. PMBs' chemo-diversity is mediated by the manifold combinations of O-methylation and hydroxylation in a definite order, which remains unsolved. To unequivocally elucidate the methylation mechanism of PMBs, 15 possible intermediates in the biosynthetic pathway of PMBs were chemically synthesized. DcOMT1-5 were highly expressed in tissues where PMBs were biosynthesized, and their expression patterns were well-correlated with the accumulation profiles of PMBs. Moreover, cell-free orthogonal tests based on the synthesized intermediates further confirmed that DcOMT1-5 exhibited distinct substrate preferences and displayed hydroxyl-group regiospecificity during the sequential methylation process. The stepwise methylation of PMBs was discovered from SAM to dihydro-piceatannol (P) in the following order: P → 3-MeP → 4-OH-3-MeP → 4-OH-3,5-diMeP → 3,3'(4'),5-triMeP → 3,4,4',5-tetraMeP (erianin) or 3,3',4,5-tetraMeP (crepidatin) → 3,3',4,4',5-pentaMeP (chrysotobibenzyl). Furthermore, the regioselectivities of DcOMTs were investigated by ligand docking analyses which corresponded precisely with the catalytic activities. In summary, the findings shed light on the sequential catalytic mechanisms of PMB biosynthesis and provide a comprehensive PMB biosynthetic network in D. catenatum. The knowledge gained from this study may also contribute to the development of plant-based medicinal applications and the production of high-value PMBs.