T7 RNA polymerase (T7 RNAP) is one of the simplest known RNA polymerases. Its unique structural features make it a critical model for studying the mechanisms of RNA synthesis. This review systematically examines the static crystal structure of T7 RNAP, beginning with an in-depth examination of its characteristic “thumb”, “palm”, and “finger” domains, which form the classic “right-hand-like” architecture. By detailing these structural elements, this review establishes a foundation for understanding the overall organization of T7 RNAP. This review systematically maps the functional roles of secondary structural elements and their subdomains in transcriptional catalysis, progressively elucidating the fundamental relationships between structure and function. Further, the intrinsic flexibility of T7 RNAP and its applications in research are also discussed. Additionally, the review presents the structural diagrams of the enzyme at different stages of the transcription process, and through these diagrams, it provides a detailed description of the complete transcription process of T7 RNAP. By integrating structural dynamics and kinetics analyses, the review constructs a comprehensive framework that bridges static structure to dynamic processes. Despite its advantages, T7 RNAP has a notable limitation: it generates double-stranded RNA (dsRNA) as a byproduct. The presence of dsRNA not only compromises the purity of mRNA products but also elicits nonspecific immune responses, which pose significant challenges for biotechnological and therapeutic applications. The review provides a detailed exploration of the mechanisms underlying dsRNA formation during T7 RNAP catalysis, reviews current strategies to mitigate this issue, and highlights recent progress in the field. A key focus is the semi-rational design of T7 RNAP mutants engineered to minimize dsRNA generation and enhance catalytic performance. Beyond its role in transcription, T7 RNAP exhibits rapid development and extensive application in fields, including gene editing, biosensing, and mRNA vaccines. This review systematically examines the structure-function relationships of T7 RNAP, elucidates the mechanisms of dsRNA formation, and discusses engineering strategies to optimize its performance. It further explores the engineering optimization and functional expansion of T7 RNAP. Furthermore, this review also addresses the pressing issues that currently need resolution, discusses the major challenges in the practical application of T7 RNAP, and provides an outlook on potential future research directions. In summary, this review provides a comprehensive analysis of T7 RNAP, ranging from its structural architecture to cutting-edge applications. We systematically examine: (1) the characteristic right-hand domains (thumb, palm, fingers) that define its minimalistic structure; (2) the structure-function relationships underlying transcriptional catalysis; and (3) the dynamic transitions during the complete transcription cycle. While highlighting T7 RNAP’s versatility in gene editing, biosensing, and mRNA vaccine production, we critically address its major limitation—dsRNA byproduct formation—and evaluate engineering solutions including semi-rationally designed mutants. By synthesizing current knowledge and identifying key challenges, this work aims to provide novel insights for the development and application of T7 RNAP and to foster further thought and progress in related fields.

In this experiment, self-assembled nanoparticles(SANs) were prepared by the pH-driven method, and Her-HCP SAN was constructed by using herpetrione(Her) and Herpetospermum caudigerum polysaccharides(HCPs). The average particle size and polydispersity index(PDI) were used as evaluation indexes for process optimization, and the quality of the final formulation was evaluated in terms of particle size, PDI, Zeta potential, and microstructure. The proposed Her-HCP SAN showed a spheroid structure and uniform morphology, with an average particle size of(244.58±16.84) nm, a PDI of 0.147 1±0.014 8, and a Zeta potential of(-38.52±2.11) mV. Her-HCP SAN significantly increased the saturation solubility of Her by 2.69 times, with a cumulative release of 90.18% within eight hours. The results of in vivo unidirectional intestinal perfusion reveal that Her active pharmaceutical ingredient(API) is most effectively absorbed in the jejunum, where both K_a and P_(app) are significantly higher compared to the ileum(P<0.001). However, the addition of HCP leads to a significant reduction in the P_(app) of Her in the jejunum(P<0.05). Furthermore, the formation of the Her-HCP SAN results in a notably lower P_(app) in the jejunum compared to Her API alone(P<0.001), while both K_a and P_(app) in the ileum are significantly increased(P<0.001, P<0.05). The absorption of Her-HCP SAN at different concentrations in the ileum shows no significant differences, and the pH has no significant effect on the absorption of Her-HCP SAN in the ileum. The addition of the transporter protein inhibitors(indomethacin and rifampicin) significantly increases the absorption parameters K_a and P_(app) of Her-HCP SAN in the ileum(P<0.05,P<0.01), whereas the addition of verapamil has no significant effect on the intestinal absorption parameters of Her-HCP SAN, suggesting that Her may be a substrate for multidrug resistance-associated protein 2 and breast cancer resistance proteins but not a substrate of P-glycoprotein.
Nanoparticles/metabolism* ; Polysaccharides/pharmacokinetics* ; Intestinal Absorption/drug effects* ; Animals ; Rats ; Particle Size ; Drugs, Chinese Herbal/pharmacokinetics* ; Male ; Rats, Sprague-Dawley ; Drug Carriers/chemistry* ; Drug Compounding ; Cucurbitaceae/chemistry*

The study was conducted to investigate the mechanism of Xinyang Tablets( XYP) in modulating the fat mass and obesity-associated protein(FTO)/N6-methyladenosine(m6A) signaling pathway to ameliorate ventricular remodeling in heart failure(HF). A mouse model of HF was established by transverse aortic constriction(TAC). Mice were randomized into sham, model, XYP(low, medium, and high doses), and positive control( perindopril) groups(n= 10). From day 3 post-surgery, mice were administrated with corresponding drugs by gavage for 6 consecutive weeks. Following the treatment, echocardiography was employed to evaluate the cardiac function, and RT-qPCR was employed to determine the relative m RNA levels of key markers, including atrial natriuretic peptide( ANP), B-type natriuretic peptide( BNP), β-myosin heavy chain(β-MHC), collagen type I alpha chain(Col1α), collagen type Ⅲ alpha chain(Col3α), alpha smooth muscle actin(α-SMA), and FTO. The cardiac tissue was stained with Masson's trichrome and wheat germ agglutinin(WGA) to reveal the pathological changes. Immunohistochemistry was employed to detect the expression levels of Col1α, Col3α, α-SMA, and FTO in the myocardial tissue. The m6A modification level in the myocardial tissue was measured by the m6A assay kit. An H9c2 cell model of cardiomyocyte injury was induced by angiotensin Ⅱ(AngⅡ), and small interfering RNA(siRNA) was employed to knock down FTO expression. RT-qPCR was conducted to assess the relative m RNA levels of FTO and other genes associated with cardiac remodeling. The m6A modification level was measured by the m6A assay kit, and Western blot was employed to determine the phosphorylated phosphatidylinositol 3-kinase(p-PI3K)/phosphatidylinositol 3-kinase(PI3K) and phosphorylated serine/threonine kinase(p-Akt)/serine/threonine kinase(Akt) ratios in cardiomyocytes. The results of animal experiments showed that the XYP treatment significantly improved the cardiac function, reduced fibrosis, up-regulated the m RNA and protein levels of FTO, and lowered the m6A modification level compared with the model group. The results of cell experiments showed that the XYP-containing serum markedly up-regulated the m RNA level of FTO while decreasing the m6A modification level and the p-PI3K/PI3K and p-Akt/Akt ratios in cardiomyocytes. Furthermore, FTO knockdown reversed the protective effects of XYP-containing serum on Ang Ⅱ-induced cardiomyocyte hypertrophy. In conclusion, XYP may ameliorate ventricular remodeling by regulating the FTO/m6A axis, thereby inhibiting the activation of the PI3K/Akt signaling pathway.
Animals ; Ventricular Remodeling/drug effects* ; Heart Failure/physiopathology* ; Signal Transduction/drug effects* ; Mice ; Male ; Alpha-Ketoglutarate-Dependent Dioxygenase FTO/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Mice, Inbred C57BL ; Humans ; Adenosine/analogs & derivatives* ; Myocytes, Cardiac/metabolism* ; Disease Models, Animal

This study investigates the effect and underlying mechanism of Guizhi Tongluo Tablets(GZTL) in treating atherosclerosis(AS) in a mouse model. Apolipoprotein E-knockout(ApoE~(-/-)) mice were randomly assigned to the following groups: model, high-, medium-, and low-dose GZTL, and atorvastatin(ATV), and age-matched C57BL/6J mice were selected as the control group. ApoE~(-/-) mice in other groups except the control group were fed with a high-fat diet for the modeling of AS and administrated with corresponding drugs via gavage for 8 weeks. General conditions, signs of blood stasis, and body mass of mice were monitored. Aortic plaques and their stability were assessed by hematoxylin-eosin, Masson, and oil red O staining. Serum levels of total cholesterol(TC), triglycerides(TG), and low-density lipoprotein cholesterol(LDL-C) were measured by biochemical assays, and those of interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), and interleukin-6(IL-6) were determined via enzyme-linked immunosorbent assay. Apoptosis was assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL). Single-cell RNA sequencing(scRNA-seq) was employed to analyze the differential expression of CD72hi macrophages(CD72hi-Mφ) in the aortas of AS patients and mice. The immunofluorescence assay was employed to visualize CD72hi-Mφ expression in mouse aortic plaques, and real-time fluorescence quantitative PCR was utilized to determine the mRNA levels of IL-1β, TNF-α, and IL-6 in the aorta. The results demonstrated that compared with the control group, the model group exhibited significant increases in body mass, aortic plaque area proportion, necrotic core area proportion, and lipid deposition, a notable decrease in collagen fiber content, and an increase in apoptosis. Additionally, the model group showcased elevated serum levels of TC, TG, LDL-C, IL-1β, TNF-α, and IL-6, alongside marked upregulations in the mRNA levels of IL-1β, TNF-α, and IL-6 in the aorta. In comparison with the model group, the GZTL groups and the ATV group showed a reduction in body mass, and the medium-and high-dose GZTL groups and the ATV group demonstrated reductions in aortic plaque area proportion, necrotic core area proportion, and lipid deposition, an increase in collagen fiber content, and a decrease in apoptosis. Furthermore, the treatment goups showcased lowered serum levels of TC, TG, LDL-C, IL-1β, TNF-α, and IL-6. The data of scRNA-seq revealed significantly elevated CD72hi-Mφ signaling in carotid plaques of AS patients compared with that in the normal arterial tissue. Animal experiments confirmed that CD72hi-Mφ expression, along with several pro-inflammatory cytokines, was significantly upregulated in the aortas of AS mice, which were downregulated by GZTL treatment. In conclusion, GZTL may alleviate AS by inhibiting CD72hi-Mφ activity.
Animals ; Drugs, Chinese Herbal/administration & dosage* ; Atherosclerosis/immunology* ; Mice ; Mice, Inbred C57BL ; Macrophages/immunology* ; Male ; Humans ; Apolipoproteins E/genetics* ; Tablets ; Tumor Necrosis Factor-alpha/genetics* ; Apoptosis/drug effects* ; Interleukin-1beta/genetics* ; Interleukin-6/genetics* ; Disease Models, Animal ; Mice, Knockout

The interactions between microorganisms and medicinal plants are crucial to the quality improvement of medicinal plants. Medicinal plants attract microorganisms to colonize by secreting specific compounds and provide niche and nutrient support for these microorganisms, with a symbiotic network formed. These microorganisms grow in the rhizosphere, phyllosphere, and endophytic tissues of plants and significantly improve the growth performance and medicinal component accumulation of medicinal plants by promoting nutrient uptake, enhancing disease resistance, and regulating the synthesis of secondary metabolites. Microorganisms are also widely used in the ecological planting of medicinal plants, and the growth conditions of medicinal plants are optimized by simulating the microbial effects in the natural environment. The interactions between microorganisms and medicinal plants not only significantly improve the yield and quality of medicinal plants but also enhance their geoherbalism, which is in line with the concept of green agriculture and eco-friendly development. This study reviewed the research results on the interactions between medicinal plants and microorganisms in recent years and focused on the analysis of the great potential of microorganisms in optimizing the growth environment of medicinal plants, regulating the accumulation of secondary metabolites, inducing systemic resistance, and promoting the ecological planting of medicinal plants. It provides a scientific basis for the research on the interactions between medicinal plants and microorganisms, the research and development of microbial agents, and the application of microorganisms in the ecological planting of medicinal plants and is of great significance for the quality improvement of medicinal plants and the green and sustainable development of TCM resources.
Plants, Medicinal/metabolism* ; Bacteria/genetics* ; Symbiosis

OBJECTIVE: To explore the effect of bear bile powder (BBP) on acute lung injury (ALI) and the underlying mechanism. METHODS: The chemical constituents of BBP were analyzed by ultra-high-pressure liquid chromatography-mass spectrometry (UPLC-MS). After 7 days of adaptive feeding, 50 mice were randomly divided into 5 groups by a random number table (n=10): normal control (NC), lipopolysaccharide (LPS), dexamethasone (Dex), low-, and high-dose BBP groups. The dosing cycle was 9 days. On the 12th and 14th days, 20 µL of Staphylococcus aureus solution (bacterial concentration of 1 × 10^-7 CFU/mL) was given by nasal drip after 1 h of intragastric administration, and the mice in the NC group was given the same dose of phosphated buffered saline (PBS) solution. On the 16th day, after 1 h intragastric administration, 100 µL of LPS solution (1 mg/mL) was given by tracheal intubation, and the same dose of PBS solution was given to the NC group. Lung tissue was obtained to measure the myeloperoxidase (MPO) activity, the lung wet/dry weight ratio and expressions of CD14 and other related proteins. The lower lobe of the right lung was obtained for pathological examination. The concentrations of inflammatory cytokines including interleukin (IL)-6, tumour necrosis factor α (TNF-α ) and IL-1β in the bronchoalveolar lavage fluid (BALF) were detected by enzyme linked immunosorbent assay, and the number of neutrophils was counted. The colonic contents of the mice were analyzed by 16 sRNA technique and the contents of short-chain fatty acids (SCFAs) were measured by gas chromatograph-mass spectrometer (GC-MS). RESULTS: UPLC-MS revealed that the chemical components of BBP samples were mainly tauroursodeoxycholic acid and taurochenodeoxycholic acid sodium salt. BBP reduced the activity of MPO, concentrations of inflammatory cytokines, and inhibited the expression of CD14 protein, thus suppressing the activation of NF-κB pathway (P<0.05). The lung histopathological results indicated that BBP significantly reduced the degree of neutrophil infiltration, cell shedding, necrosis, and alveolar cavity depression. Moreover, BBP effectively regulated the composition of the intestinal microflora and increased the production of SCFAs, which contributed to its treatment effect (P<0.05). CONCLUSIONS BBP alleviates lung injury in ALI mouse through inhibiting activation of NF-κB pathway and decreasing expression of CD14 protein. BBP may promote recovery of ALI by improving the structure of intestinal flora and enhancing metabolic function of intestinal flora.
Animals ; Acute Lung Injury/pathology* ; Lipopolysaccharides ; Ursidae ; Gastrointestinal Microbiome/drug effects* ; Bile/chemistry* ; Lipopolysaccharide Receptors/metabolism* ; Powders ; Male ; Lung/drug effects* ; Mice ; Peroxidase/metabolism* ; Signal Transduction/drug effects* ; Cytokines/metabolism*

OBJECTIVE: To investigate the effectiveness of Xuanshen Yishen Decoction (XYD) in the treatment of hypertension. METHODS: Hospital electronic medical records from 2019-2023 were utilized to emulate a randomized pragmatic clinical trial. Hypertensive participants were eligible if they were aged ⩾40 years with baseline systolic blood pressure (BP) ⩾140 mm Hg. Patients treated with XYD plus antihypertensive regimen were assigned to the treatment group, whereas those who followed only antihypertensive regimen were assigned to the control group. The primary outcome assessed was the attainment rate of intensive BP control at discharge, with the secondary outcome focusing on the 6-month all-cause readmission rate. RESULTS: The study included 3,302 patients, comprising 2,943 individuals in the control group and 359 in the treatment group. Compared with the control group, a higher proportion in the treatment group achieved the target BP for intensive BP control [8.09% vs. 17.5%; odds ratio (OR)=2.29, 95% confidence interval (CI)=1.68 to 3.13; P<0.001], particularly in individuals with high homocysteine levels (OR=3.13; 95% CI=1.72 to 5.71; P<0.001; P for interaction=0.041). Furthermore, the 6-month all-cause readmission rate in the treatment group was lower than in the control group (hazard ratio=0.58; 95% CI=0.36 to 0.91; P=0.019), and the robustness of the results was confirmed by sensitivity analyse. CONCLUSIONS XYD could be a complementary therapy for intensive BP control. Our study offers real-world evidence and guides the choice of complementary and alternative therapies. (Registration No. ChiCTR2400086589).
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Antihypertensive Agents/pharmacology* ; Blood Pressure/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Hypertension/physiopathology* ; Patient Readmission ; Treatment Outcome

Objective To observe the effect of canagliflozin combined with enalapril on diabetic nephropathy(DN).Methods DN patients were randomly divided into control group and treatment group.All patients in 2 groups received basic treatment of recombinant human insulin injection,and the control group was orally administered enalapril tablet 10 mg(qd).The treatment group was given orally canagliflozin tablet 100 mg(qd)on the basis of the control group.Both groups were treated for 8 weeks.Renal function,blood glucose index,serum vascular endothelial growth factor(VEGF),transforming growth factor-β(TGF-β),homocysteine(HCY)levels,clinical efficacy and incidence of adverse drug reactions were compared between 2 groups.Results There were 71 cases were included in the control group and 73 cases in the treatment group.After treatment,β2 microglobulin(β2-MG)in treatment group and control group were(0.21±0.03)and(0.28±0.04)mg·L-1;blood urea nitrogen(BUN)were(4.23±0.42)and(5.58±0.65)mmol·L-1;serum creatinine(SCr)were(89.32±8.29)and(101.25±10.18)pmol·L-1;24 h microalbumin(mAlb)were(49.38±5.06)and(58.21±6.43)mg;glycosylated hemoglobin(HbA1c)were(6.10±0.11)％and(6.45±0.16)％;2 h postprandial blood glucose levels were(6.05±0.78)and(7.68±1.82)mmol·L-1;fasting blood glucose(FBG)were(5.02±0.32)and(5.67±0.65)mmol·L-1;VEGF levels were(350.18±20.04)and(389.04±24.16)pg·mL-1;TGF-β were(148.32±16.57)and(168.24±20.02)pg·mL-1;HCY were(13.12±2.38)and(19.35±3.21)pmol·L-1,the differences were statistically significant(all P＜0.05).After treatment,the total effective rate of treatment group and control group were 83.56％(61 cases/73 cases)and 67.61％(48 cases/71 cases),the difference was statistically significant(P＜0.05).The total incidence of adverse drug reactions in treatment group and control group were 6.85％and 4.23％,with no significant difference(P＞0.05).Conclusion Canagliflozin combined with enalapril is effective in the treatment of diabetic nephropathy,which can improve renal function,regulate blood glucose metabolism,and down-regulate serum VEGF,TGF-β and HCY levels,and is safe and reliable.

Objective To explore the correlation between sleep status and traditional Chinese medicine(TCM)constitution types of sub-healthy population in Lingnan area.Methods From May 2022 to May 2023,an investigation was carried out in a sub-healthy population of 688 persons who lived in Shenzhen for more than 5 years,had no serious cardiovascular disease and were confirmed by the sub-health rating scale.The questionnaire survey of Pittsburgh Sleep Quality Index(PSQI)scale and the TCM constitution classification rating scale was conducted,and multiple linear regression analysis was performed to explore the correlation between the sleep status and TCM constitution types.Results(1)A total of 688 questionnaires were released,of which 19 were lost to follow-up,and 669 were responded.After weeding out the 29 invalid questionnaires,640 valid questionnaires were finally included for the analysis.(2)According to the PSQI score,the population was divided into excellent sleep group(total PSQI score＜8)of 350 cases and poor sleep group(total PSQI score≥8)of 290 cases.The item scores of time for falling asleep,sleep time and sleep disorder as well as the total PSQI score of the excellent sleep group were significantly lower than those of the poor sleep group(P＜0.05 or P＜0.01).(3)The persons with excellent sleep usually had the balanced constitution(86.86%),while the persons with poor sleep often had the biased constitution(79.64%).The top three biased constitution types in the persons with poor sleep were damp-heat constitution(15.52%),phlegm-damp constitution(13.79%)and qi-stagnation constitution(13.10%).(4)Multiple linear regression analysis showed that the time for falling asleep was positively correlated with phlegm-damp constitution and qi-stagnation constitution(P＜0.01),and was negatively correlated with balanced constitution(P＜0.05);the sleep efficiency was positively correlated with damp-heat constitution and inherited special constitution(P＜0.05 or P＜0.01),and was negatively correlated with balanced constitution(P＜0.05);sleep disorder was positively correlated with qi-stagnation constitution and yin-deficiency constitution(P＜0.01);hypnotic drugs were positively correlated with yin-deficiency constitution(P＜0.01);daytime dysfunction was positively correlated with phlegm-damp constitution(P＜0.05).Conclusion The sleep status of sub-healthy population in Lingnan area has a certain correlation with TCM constitution types.Damp-heat constitution,phlegm-damp constitution,qi-stagnation constitution,yin-deficiency constitution,balanced constitution and inherited special constitution are the six constitution types that affect sleep status.It is of great significance to guide the sub-healthy population to achieve the purpose of prevention before illness by improving their constitution after the identification of TCM constitution types.

Objective To investigate the relationship between single nucleotide polymorphisms(SNPs)in the eNOS gene and genetic susceptibility to systemic lupus erythematosus(SLE)in Hainan.Methods Blood samples were collected from SLE patients(SLE group,n=214)and healthy controls(control group,n=214)from January 2020 to December 2022 at the First Affiliated Hospital of Hainan Medical College and Hainan Provincial People's Hospital.The bases of eNOS gene rs3918188,rs1799983 and rs1007311 loci in each group were detected by SNaPshot sequencing technology.Logistic regression was used to analyze the correlation between genotypes,alleles and gene models(dominant model,recessive model,and overdominant model)of the above 3 target loci of the eNOS gene and genetic susceptibility to SLE.Haplotype analysis was conducted using HaploView 4.2 software to investigate the relationship between haploid and genetic susceptibility to SLE at each site.Results The results of logistic regression analysis revealed that the CC genotype and the C allele at rs3918188 locus were risk factors for genetic susceptibility to SLE(CC vs.AA:OR=2.449,P<0.05;C vs.A:OR=2.133,P<0.001).In recessive model at rs3918188 locus,CC genotype carriers had an increased risk of SLE development compared with AA+AC genotype carriers(OR=2.774,P<0.001).In contrast,in overdominant model at this locus,AC genotype carriers had a decreased risk of SLE occurrence compared with AA+CC genotype carriers(OR=0.385,P<0.001).In addition,polymorphisms of rs1799983 and rs1007311 were not associated with susceptibility to SLE in genotype,allele type and the 3 genetic models(P>0.05).Haplotype analysis revealed a strong linkage disequilibrium between the rs1007311 and rs1799983 loci of the eNOS gene,but no significant correlation was found between haplotype and genetic susceptibility to SLE(P>0.05).Conclusion The CC genotype and C allele at rs3918188 locus of eNOS gene may be risk factors for SLE in Hainan,while the risk of SLE occurrence is reduced in carriers of AC genotype under the overdominant model.