Cardiovascular diseases (CVDs) and malignant tumors are the main causes of death worldwide. The etiology study of CVDs and malignant tumors has found a series of widely recognized risk factors. Medical practice and medical theory usually focus on one of the diseases, but more and more evidence reveals that malignant tumors usually involve the cardiovascular system, thus leading to thromboembolism, heart failure, etc. Anti-cancer treatment proves to induce CVDs, while CVDs seem to increase the risk of malignant tumors. This situation requires researchers to conduct further combined crossover study on both CVDs and malignant tumors. In this review, we discuss the potential common risk factors of cardiovascular diseases and malignant tumors, the pathological and physical mechanism of the two kinds of diseases, the cardiac toxicity induced by tumor therapy and the impact of cardiovascular drugs on cancer from the perspective of cardio-oncology, and in the endput forward the prospect of prevention and treatment.

The senescence-associated secretory phenotype (SASP) is a generic term for the secretion of a series of cytokines such as pro-inflammatory factors, chemokines and proteases, and is a key feature of senescent cells. SASP is a double-edged sword that can resist a harmful environment in normal cells, but with the decline of body function, the massive secretion of cytokines, chemokines and proteases accelerates aging while inducing inflammation, leading to the development of various aging-related diseases. This article reviews the composition and physiological functions of SASP, the changes in SASP during aging, the regulatory pathways associated with SASP, and the anti-aging drugs that regulate SASP. This article aims to present a more comprehensive understanding of SASP and lay the foundation for SASP-based anti-aging research and the discovery of new targets for anti-SASP drugs.

Nonalcoholic fatty liver disease (NAFLD) is a genetic and environmental factor-associated metabolic disease that can lead to fibrosis, cirrhosis and hepatocellular carcinoma. In recent decades the prevalence of NAFLD has increased, but effective pharmacotherapy is limited. Treatment regimens in traditional Chinese medicine (TCM) have made significant contributions to the control of NAFLD, but underlying mechanisms are far less elucidated. Increasing evidence suggests that gut microbiota play a crucial role in the pathogenesis and development of diseases including NAFLD. The outcomes of such research open a new approach in identifying the molecular mechanisms of TCM. Here we review the evidence that gut microbiota might be a target in the treatment NAFLD using TCM.

Peptides have been extensively used in the fields of gene/drug delivery and disease targeting therapy. However, natural peptides are sensitive to protease digestion with short circulatory half-lives in vivo. Many studies on structural modifications of peptides have been reported to improve the delivery or therapeutic effect. In this review we focus on the recent literature on peptide stability in accordance with different structural modifications and summarize the methods and influential factors that are involved in the improvement of stability and half-life in vivo. This review will provide the scientific basis and theoretical references for further investigations and applications in vivo.

The resistance and dose limitation of tumors is a serious obstacle to cytotoxic drug therapy in the field of medical oncology. Nitric oxide (NO) is a powerful adjuvant for tumor hypersensitivity for traditional chemotherapy and radiation therapy. The concentration of NO plays an important role in affecting its anti-tumor effect. This review summarizes the mechanism of concentration-dependent effects of NO on tumor cells and the mechanism of chemotherapy sensitization. It provides evidence for rational use of NO to exert anti-tumor effects, and overcoming multidrug resistance and anti-tumor drug development.

Physiologically based pharmacokinetic (PBPK) modeling is an important tool to predict pharmacokinetic or pharmacodynamic profiles in special populations, especially in children and infants where designing and conducting clinical studies is difficult. The application of PBPK modeling can effectively promote the development of pediatric drugs and their clinical use. At present, PBPK modeling of pediatric populations is mainly applied in clinical trial design, drug-drug interaction (DDI) risk assessment, and dose selection in children. This review discusses the advantages of PBPK modeling in pediatric drug research and summarizes how to extrapolate a PBPK model from adults to children. The theoretical basis for pediatric PBPK models, the modelling process and important physiological parameters during the modeling process are introduced. Some successful applications of PBPK modeling in pediatric drug research and development are also presented. This review also analyzes the current limitations and future directions of pediatric PBPK modeling.

Plant polyphenols have a wide range of pharmacological activities and application prospects. Liquid polyphenol preparations have special physical phases and complex chemical compositions, with problems such as poor stability and easy precipitation during production and marketing. Taking the multi-precipitation mechanism of plant polyphenol liquid preparations as an example, we discuss the chemistry and composition of the precipitation, how it forms, whether precipitationcan be controlled, and the interaction law of three precipitation approaches. An unstable mechanism model is proposed where hydrolyzed tannin hydrolysis and catechin non-enzymatic oxidative polymerization repeatedly induces associative colloid aggregation and precipitation. This study explains the complex physicochemical changes in polyphenol solutions and the microcosmic mechanism of instability in the induced system and proposes a steady state reconstruction of liquid polyphenol preparation consistent with the common law of precipitation and control. It has scientific significance for promoting the development and manufacture of high quality liquid polyphenol preparations.

The coagulation Ⅷ factor (FⅧ) contains eight pairs of disulfide bonds, which are involved in maintaining its structure and function. It has been demonstrated that the disulfide bond between Cys¹⁸⁹⁹/Cys¹⁹⁰³ of the A3 domain in the light chain impedes secretion. In our previous work, an engineered inter-chain disulfide in the B domain-deleted FⅧ (BDD-FⅧ) promoted heterodimer assembly and secretion of separately expressed heavy and light chains. In this study, we constructed two BDD-FⅧ variants, one of which contains an engineered inter-chain disulfide bond (F8C) between Met⁶⁶² > Cys and Asp¹⁸²⁸ > Cys mutations and another contains an endogenous A3 domain with a disrupted disulfide bond from F8C (F8CG) by replacement of Cys¹⁸⁹⁹ and Cys¹⁹⁰³ with Gly in F8C. We explored their function and secretion. By transducing F8C and F8CG into HEK293 and COS-7 cells, the formation of disulfide bonds and the secretion and coagulation activity of the two variants in the culture media and their binding affinity for von Willebrand factor (vWF) could be observed. The results show that variants F8C and F8CG are mainly the disulfide bonded heavy and light chain dimer, while the wild type BDD-FⅧ (F8) is dominated by the easily dissociated heavy and light chain dimer. The secretion and activity of F8C was significantly higher than that of F8, while the secretion and activity of F8CG was significantly higher than that of F8C. The vWF binding of the two variants is similar to F8. This indicates that the BDD-FⅧ variant F8CG may be attractive molecule for protein replacement and as a transgene in gene-therapy strategies. These findings are encouraging for future studies targeting disulfide bond elimination for further enhancement of FⅧ secretion.

The p21-activated kinase 1 (PAK1) is a member of the P21-activated protein kinase family that plays an important role in the proliferation and on cogenesis of pancreatic cancer. PAK1 is an important target for the treatment of pancreatic cancer. At present, akinase inhibitor targeting PAK1 is still in the preclinical research stage. Therefore, screening for new PAK1 kinase inhibitors is of great significance. In this study the natural compound celastrol was found to have a significant inhibitory effect on PAK1, with an IC₅₀ value of 3.614 μmol·L^-1. Molecular docking results showed that celastrol had good binding to PAK1. An MTT assay indicated that celastrol inhibited the proliferation of pancreatic cancer cells BxPC-3 and PANC-1. Mechanistic studies revealed that the inhibition of pancreatic cancer cells by celastrol was reversed by PAK1 siRNA. Celastrol inhibited PAK1 and the subsequent activation of downstream signaling pathways, thereby activating apoptosis signaling pathways and triggering apoptosis in pancreatic cancer cells. These findings suggested that celastrol induced apoptosis in pancreatic cancer cells by suppressing the PAK1 kinase signaling pathway and has potential value for the treatment of pancreatic cancer.

Cionbufagin has anti-inflammatory and analgesic effects. It is of great value in the treatment of bone cancer pain, but its mechanism is still unclear. To generate a bone metastasis model of breast cancer, 4×10⁵ Walker-256 cells were inoculated into the left hind limb of SD rats. The experimental protocol was approved by the Medical Laboratory Animal Ethics Committee of Medical College of China Three Gorges University. Rats were randomly divided into sham, model, cionbufagin, morphine, saline, minocycline, microglia inhibitor (RS102895) and co-treatment with cionbufagin and minocycline group. The cionbufagin (5 mL·kg^-1, i.p.), morphine (8 mg·kg^-1, i.p.) and co-treatment groups (included cionbufagin 5 mL·kg^-1, i.p.) received continuous administration from day 9 to day 21. The saline, minocycline (2.5 μg·μL^-1, 20 μL), RS102895 (1.5 μg·μL^-1, 20 μL) and co-treatment groups (included minocycline 2.5 μg·μL^-1, 20 μL) received continuous administration by intrathecal cannulation from day 12 to day 21. Bone destruction of the left hind limb of rats was detected by hematoxylin-eosin staining (H&E). The pain threshold before treatment and at day 2, 5, 7, 9, 12, 14, 17 and 20 was measured by behavioral indexes. Activation and expression of a microglia marker (Iba-1) was determined by immunofluorescence and Western blot. The level of tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), and interleukin-6 (IL-6) in rat spinal cord was measured by enzyme-linked immunosorbent assay (ELISA). H&E results showed that cionbufagin effectively inhibited the destruction of bone marrow in rats with bone cancer pain; cionbufagin treatment significantly increased the mechanical and thermal pain threshold. Immunofluorescence showed that cionbufagin effectively inhibited the activation of microglia in the spinal dorsal horn. Western blot analysis confirmed that the activation of microglia in the spinal dorsal horn was inhibited by cionbufagin treatment. It was also found that the CCL2/CCR2 pathway may be involved in the analgesic effect of cionbufagin. These results suggest that cionbufagin can effectively alleviate bone cancer pain, possibly by inhibiting the release of inflammatory factors and the activation of spinal microglia cells through the CCL2/CCR2 pathway.

In this study a D-galactose-induced aging rat model combined with ¹H NMR of serum and liver metabolomics were used to explore the anti-aging effect and the potential metabolic regulatory mechanism of Scutellaria baicalensis Georgi leaves. All procedures involving animal treatment were approved according to the Committee on the Ethics of Animal Experiments of Shanxi University. The results of physical characteristics, an open field test and serum biochemical indexes indicated that Scutellaria baicalensis Georgi leaves had an anti-aging effect that could ameliorate the characteristics of aging rats such as acquired hair loss and slow response, improve the spontaneous activity of aging rats, and decrease lipid peroxidation and glycosylation damage induced by D-galactose. Serum and liver metabolomics further revealed that Scutellaria baicalensis Georgi leaves could decrease serum and liver metabolism disturbances in aging rats, mainly through different metabolites and metabolic pathways. Specifically, 12 differential metabolites including glutamine and glutamate, 11 metabolic pathways including D-glutamine and D-glutamate metabolism and alanine, aspartate and glutamate metabolism in serum were significantly altered after the treatment. Simultaneously, five differential metabolites such as α-glucose and β-glucose, two metabolic pathways that are glycolysis or gluconeogenesis, and starch and sucrose metabolism in the liver were markedly altered.

¹H NMR-based metabonomic analysis was used to elucidate the hypoglycemic mechanism of Astragalus Radix and Dioscoreae Rhizomacomes. Thirty-seven SD rats were divided into four groups:model group (M group), control group (C group), Astragalus Radix and Dioscoreae Rhizomacomes group (HS group), metformin group (Y group). A T2DM model was induced with a high fat diet and streptozotocin (STZ). Drug was continuously administered for 8 weeks, after which blood and the kidneys were collected to determine the biochemical index and the kidney coefficients of each group. Using ¹H NMR metabolomics technology, we measured the metabolites in the urine of rats in each group to identify appropriate biomarkers. The results showed that total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (L-DLC), blood urea nitrogen (BUN), hemoglobin A1c (HbA1c) and the kidney coefficients were significantly increased with high density lipoprotein (H-DLC) significantly decreased in the diabetic group, but these changes were largely reversed with treatment with Astragalus Radix and Dioscoreae Rhizomacomes. A total of 20 biomarkers were found in rat urine in the diabetic group and Astragalus Radix and Dioscoreae could reverse the changes of 16 of these metabolites to varying degrees, similar to that of metformin (200 mg·kg^-1). The changes in metabolomics mainly involved butanoate metabolism, the tricarboxylic acid (TCA) cycle, taurine and hypotaurine metabolism, synthesis and degradation of ketone bodies, and pyruvate metabolism. Dioscoreae Rhizomacomes and Astragalus Radix may have a therapeutic role in the treatment of diabetes through the above five metabolic pathways, revealing the possible therapeutic mechanisms for Dioscoreae Rhizomacomes and Astragalus Radix.

We compared the pharmacokinetic and pharmacodynamic profiles of desmopressin acetate after intraocular, intravenous and intragastric administration in rabbits to better understand the systemic delivery of peptide drugs through intraocular administration. Fifteen rabbits were randomly divided into three groups (intraocular administration, 7 μg·kg^-1; intravenous administration, 0.7 μg·kg^-1; and intragastric administration, 7 μg·kg^-1). Blood samples were taken from the heart at predetermined time points after dosing and the plasma desmopressin concentration was analyzed by enzyme-linked immunosorbent assay (ELISA). Another 21 rabbits were randomly divided into three groups (intraocular administration, 7 μg·kg^-1; intravenous administration, 0.7 μg·kg^-1; intragastric administration, 7 μg·kg^-1) for a pharmacodynamics study. Urine was collected at predetermined intervals after dosing. The pharmacokinetic parameters after intravenous administration were as follows:C_max was 143.0 pg·mL^-1; the area under the plasma concentration-time curve for desmopressin (AUC_0-t) was 999.9 pg·h·mL^-1. The pharmacokinetic parameters after intraocular administration were as follows:t_max was 5 min, C_max was 125.6 pg·mL^-1, AUC_0-t was 873.1 pg·h·mL^-1, and absolute bioavailability (F) was 8.7%. The pharmacokinetic parameters after intragastric administration were as follows:t_max was 10 min, C_max was 104.1 pg·mL^-1, AUC_0-t was 451.8 pg·h·mL^-1, and absolute bioavailability was 4.5%. Intraocular administration and intravenous administration of one tenth of the dosage showed a similar effect, and the urine volume remained decreased for 12 h, but urine volume increased significantly in the second collection period after intragastric administration, and there was no decrease in volume 12 h after dosing. This study demonstrates that peptide drugs such as desmopressin can be absorbed more rapidly after intraocular administration than after intragastric administration and can exert systemic therapeutic effects. In this study, the program of animal testing had been approved by the Laboratory Animal Care and Use Committee at Anhui University of Chinese Medicine.

Based on the structure of inhibitors XL765 and WR23, the quinoxaline scaffold was selected as an attractive structure for drug design. In this protocol, the 2-position of quinoxaline was modified with a substituted phenoxy fragment. Meanwhile, the linking chain at the 3-position was changed to a sulfonyl hydrazine or was removed. A series of substituent groups were added at the 6-position of the quinoxaline scaffold. Twenty-two quinoline derivatives were designed and synthesized, and their structures were confirmed by ¹H NMR, ¹³C NMR, and ESI-MS. All compounds were screened for anti-tumor activity in vitro in A549, MCF-7, HCT-116 and HepG2 cancer cells. The results showed that P6b was effective, P6e and P6f had better activity against HCT116 (IC₅₀=3.24, 4.78 and 4.50 μmol·L^-1), and P6d had strong inhibitory effect on MCF-7 (IC₅₀=0.228 7 μmol·L^-1).

Two new trichilin-type limonoids were isolated from the fruits of Trichilia connaroides along with two known limonoids, 3α-deacetylamoorastatin (3) and mesendanins K (4). Their planar structure and relative configuration were elucidated by comprehensive analyses of HR-ESI-MS, ¹H NMR, ¹³C NMR, HSQC, HMBC and ROESY data. An antitumor activity assay showed that compounds 1, 2 and known compound 4 had weak cytotoxicity against a human cervical cancer cell line (HeLa).

A new carbazole alkaloid was isolated from the aqueous extract of the stems of Clausena lansium (Lour.) Skeels by various chromatographic methods, including HPD-100, PRP-512A, silica gel, and reverse phase C18. Its structure was determined by spectroscopic and chemical methods, including UV, IR, HR-ESI-MS, 1D/2DNMR and ECD. Compound 1, named as Claulamine F, showed no antimicrobial activity on Staphylococcus aureus, Escherichia coli or Pseudomonas aeruginosa. In addition, compound 1 exhibited no cytotoxicity on five kinds of cancer cells through MTT methods.

A QuEChERS-ultra high performance liquid chromatography-tandem mass spectrometry method was developed for qualitative screening of 169 veterinary drug residues in bear bile powder, including β-agonists and inhibitors, antibiotics (penicillins, β-lactams, sulfomamides, quinolones, chloramphenicals, tetracyclines, nitroimidazoles, macrolides, polyethers, etc.), antiviral drugs, anthelminitics, steroid hormones, nonsteroidal antiinflammatory drugs (NSAIDs) and sedatives. The samples were extracted by Na₂EDTA-McIlvaine buffer solution and 5% fomic acid-acetonitrile solution, then purified by dispersive solid phase extraction. Detection of veterinary drug residues by ultra high performance liquid chromatography-triple quadrupole mass spectrometry was conducted and qualitative confirmed by ion ratios. The limits of detection of 169 veterinary drugs were 1-1 000 μg·kg^-1. The method is simple and fast, which had been used for the analysis of actual samples, and can be extended to the detection of similar matrix.

Notoginseng (Sanqi), the root of Panax notoginseng (Burk.) F. H. Chen (Araliaceae), is one of the most valuable traditional Chinese medicines (TCM). It has been widely used in China with a long history for treatment of haemorrhage, edema, and cardiovascular disorders. Steamed P. notoginseng has been considered to have stronger therapeutic functions than raw P. notoginseng in the treatment of tumors, cardiovascular diseases, etc. Saponins are the principal chemical and pharmacological constituents in P. notoginseng. Thus, it is of great importance to determine the constituent saponins and determine any differences between fresh P. notoginseng and steamed P. notoginseng. We used a rapid and direct analytical method based on liquid extraction surface analysis combined with mass spectrometry (LESA-MS) to identify saponins in the xylem, phloem and cambium of fresh and steamed P. notoginseng root slices. The results revealed that ginsenosides Rg1, Rb1, Re, Rd, notoginsenoside R1 and their malonyl group versions were most abundant in fresh root slices, while in steamed slices ginsenosides Rg5, Rk1 and other minor polar components could be detected, and the relative content of large polar components was lower. The described method is fast, robust and sensitive and the process does not need traditional and cumbersome pretreatment such as crushing, extraction and separation. It is the first non-destructive study on the differences in saponins between fresh and steamed P. notoginseng root slices.

A pre-column derivatization and ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS) method was developed for qualitative and quantitative determination of medium-and short-chain fatty acids in mice feces, and was further applied to evaluate variations in the feces of mice before and after antibiotic treatment. This animal experiment had been approved by Animal Experimental Ethics Committee of Jiangsu Province Academy of Traditional Chinese Medicine. By optimizing the derivatization conditions and UHPLC-QTOF-MS/MS parameters a new UHPLC-QTOF-MS/MS method with 3-nitrophenylhydrazine as the derivatization reagent was developed for simultaneous determination of 16 medium-and short-chain fatty acids. Validation studies showed that the linearity of the calibration curves was good (R² > 0.99), the RSD of intra-day and inter-day precision was less than 10%, the repeatability RSD was less than 6%, the recovery rate was between 80%-120% at three spiked levels, and the stability RSD was less than 7% within 36 h. The types and amounts of the detected medium-and short-chain fatty acids in feces significantly changed after the mice were treated with antibiotics. The content of formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, and lactic acid decreased, whereas that of heptanoic acid and succinic acid increased significantly. All these results suggest that the newly established method is accurate and reliable, and can be used for determination of medium-and short-chain fatty acids in feces.

To prepare the mimetic exosomes and co-delivery proteins and nucleic acids, and achieve efficient and safe co-delivery of multi-component drugs, an optimized formulation was designed by modifying a polylactic acid-glycolic acid copolymer (PLGA) matrix with a cationic lipid excipient dioleyl trimethylammonium propane (DOTAP), and a PLGA/DOTAP nanoparticles packaged protein and nucleic acid was prepared by double emulsion method, and the outermost membrane structure prepared by reverse phase evaporation method and consists of 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1, 2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), 1, 2-distearoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol and membrane proteins. The structure of the mimetic exosomes is formed by ultrasonic dispersion and extrusion, and analyzed its characteristics and nature of the transfer effect. The size of mimetic exosomes was about 156.13 nm, with negative charge (-18.23 ±0.57 mV), and it could efficiently co-transfer protein and siRNA, and siRNA could effectively inhibit the expression of target gene Trim28. The mimetic exosomes simulate the structure of exosomes and achieve safe and efficient co-delivery of multi-component drugs.

Melanoma is a malignant tumor with a high degree of malignancy. The incidence of melanoma keeps increasing annually. In this study, a melanoma targeted hyaluronic acid (HA) nanogel was synthesized via crosslinking of thiolated HA with terminally functionalized F127-TPGS mixed micelles. Its stability in vitro was evaluated by the average particle size, and the cytotoxicity of the nanogel was investigated by in vitro cell based assays. Next, cell uptake studies were performed to quantitatively and qualitatively investigate the uptake of the nanogels in B16F10 cells. A small sized nanogel with a diameter of 30 nm was synthesized, which was proven to be minimally cytotoxic against both 3T3 or B16F10 cells. Compared with 3T3 cells with low levels of CD44, B16F10 cells with high levels of CD44 showed significantly higher cell uptake efficiency (P < 0.05).

3-Hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) is the first rate-limiting enzyme of terpenoid biosynthesis in the mevalonic acid pathway (MVA) pathway. It is an important regulatory site in terpenoids metabolism pathway in the cytoplasm. According to the transcriptome database of Cinnamomum camphora, two HMGRs named CcHMGR1 (GenBank:MN163055) and CcHMGR2 (GenBank:MN163056) were cloned by cDNA from C. camphora. The ORF of CcHMGR1 and CcHMGR2 is composed of 1 689 bp and 1 683 bp, respectively, encoding 562 and 560 amino acids. The bioinformatics analysis of CcHMGR1 and CcHMGR2 indicated that the molecular weight of the encoded protein is 59.819 kDa and 59.397 kDa, with a theoretically isoelectric point of 8.20 and 8.61, respectively. There are 2 transmembrane structures without signal peptide existing in the encoded amino acid of CcHMGRs. The analysis of sequence alignment and phylogenetic tree showed that the CcHMGRs belonged to the HMGR family. The camphor is divided into five chemitypes, according to the main chemical compounds in C. camphora. The results of the real time PCR indicated that the expression level of CcHMGRs in Cineol type was higher than that in Linalool type, iso-nerolidol type, Camphor type and Borneol type. CcHMGRs expressed highest in roots and lowest in branches. In this study, the cDNA full length of CcHMGRs were cloned from C. camphora for the first time. Our results revealed that the expression level of CcHMGRs were different among five chemical types and different plant tissues, and the research provides foundation for further study of the terpenoids biosynthetic pathway in C. camphora.

In order to explore MYB transcription factors related to developmental processes and secondary metabolism in Morinda officinalis, we analyzed MoMYB expression based on transcriptome data from three tissues (root, stem and leaf). We used this analysis to provide a theoretical foundation for regulating the metabolism of M. officinalis. RNA-seq data along with the five databases including PFAM and plantTFDB and others were used to screen and classify MoMYB, including GO functional annotation and classification, subcellular localization, signal peptide prediction, conserved motif discovery, and comparative phylogenetic analysis. RT-qPCR was carried out to detect tissue-specific expression differences of MoMYB genes. According to transcriptome data, 109 MoMYB sequences were identified and divided into four classes, containing 51 sequences related to R2R3-MYB. Subcellular localization analysis indicated that a majority of sequences were located in nucleus. Blast2GO analysis showed that 109 MoMYB sequences were classified into three major functional ontologies including molecular function (112), biological processes (76) and cellular components (239). The R2-MYB conserved motif of 51 R2R3-MYB sequences possessed three significantly conserved tryptophan residues, whereas a phenylalanine replaced the first tryptophan in R3-MYB. The results of multiple sequence alignment and phylogenetic analysis revealed that the R2R3-MYB was distributed in all subgroups, apart from the S10, S19 and S21 subgroups. RT-qPCR indicated that several R2R3-MYB genes were differentially expressed among the three tissues, and this finding was consistent with transcriptome data. The 109 MoMYB sequences were annotated and divided into different classes, which lays the foundation for further study on MYB transcriptional factors in M. officinalis.

The whole chloroplast genome of the medicinal plant Paeonia mairei H. Lév. was sequenced using the Illumina HiSeq X Ten platform and then assembled, annotated, and characterized by bioinformatic methods in this study. The complete chloroplast genome of P. mairei is 152 731 bp in length with the typical quadripartite structure, which consists of a large single copy-region (LSC, 84 402 bp), a small single copy-region (SSC, 16 969 bp), and a pair of inverted repeat regions (IRa and IRb, 25 680 bp), with an overall GC content of 38.4%. A total of 136 predicted genes, including 90 protein-coding genes, 38 tRNA genes and eight rRNA genes were identified. Among these, seven protein-coding genes, seven tRNA genes and four rRNA genes were found duplicated in the IR regions. In addition, 28 dispersed repeats, 10 tandem repeats, and 64 simple sequence repeats were detected within the whole chloroplast genome of P. mairei. Comparative analyses between 12 Peaonia species showed that the chloroplast genomes are highly conserved in length, gene content, gene order, and GC content. Meanwhile, the noncoding sequences (intergenic regions and introns) show a higher variation than the protein coding sequences, and sequences from the LSC region and SSC region are more variable than those from the IR regions. P. mairei was inferred forming in a distinct clade with P. lactiflora, P. obovate, and P. anomala subsp. veitchii with a 100% bootstrap value and is phylogenetically closest to P. lactiflora. These results may provide a basis for further genetic studies and the development and utilization of medicinal P. mairei.