Genome-Wide Identification and Analysis of WRKY Gene Family in Melastoma dodecandrum.

WRKY is one of the largest transcription factor families in plants and plays an important role in plant growth and development as well as in abiotic and biological stresses. However, there is little information about the WRKY family in Melastoma dodecandrum. In this study, 126 WRKY members were identified in M. dodecandrum. According to phylogenetic analysis, they were divided into three major groups, and group II was further divided into five subgroups. MedWRKY genes were unevenly distributed on 12 chromosomes. Additionally, the gene structure and sequence composition were similar within the same group and differed between groups, suggesting their functional diversity. The promoter sequence analysis identified a number of cis-acting elements related to plant growth and development, stress response, and secondary metabolite synthesis in the WRKY gene family. The collinearity analysis showed that gene replication events were the main driving force of MedWRKY gene evolution. The transcriptome data and RT-qPCR analysis suggested that MedWRKY genes had higher expression in the roots and ripe fruit of M. dodecandrum. In short, this paper lays a foundation for further study of the functions and molecular mechanism of M. dodecandrum WRKY gene family.

Bioinformatic Assessment and Expression Profiles of the AP2/ERF Superfamily in the Melastoma dodecandrum Genome.

AP2/ERF transcription factors play crucial roles in various biological activities, including plant growth, development, and responses to biotic and abiotic stressors. However, limited research has been conducted on the AP2/ERF genes of Melastoma dodecandrum for breeding of this potential fruit crop. Leveraging the recently published whole genome sequence, we conducted a comprehensive assessment of this superfamily and explored the expression patterns of AP2/ERF genes at a genome-wide level. A significant number of genes, totaling 218, were discovered to possess the AP2 domain sequence and displayed notable structural variations among five subfamilies. An uneven distribution of these genes was observed on 12 pseudochromosomes as the result of gene expansion facilitated by segmental duplications. Analysis of cis-acting elements within promoter sites and 87.6% miRNA splicing genes predicted their involvement in multiple hormone responses and abiotic stresses through transcriptional and post-transcriptional regulations. Transcriptome analysis combined with qRT-PCR results indicated that certain candidate genes are involved in tissue formation and the response to developmental changes induced by IAA hormones. Overall, our study provides valuable insights into the evolution of ERF genes in angiosperms and lays a solid foundation for future breeding investigations aimed at improving fruit quality and enhancing adaptation to barren land environments.

Genome-Wide Identification and Characterization of the GRF Gene Family in Melastoma dodecandrum.

Growth-regulating factor (GRF) is a kind of transcription factor unique to plants, playing an important role in the flowering regulation, growth, and development of plants. Melastoma dodecandrum is an important member of Melastomataceae, with ornamental, medicinal, and edible benefits. The identification of the GRF gene family in M. dodecandrum can help to improve their character of flavor and continuous flowering. The members of the GRF gene family were identified from the M. dodecandrum genome, and their bioinformatics, selective pressure, and expression patterns were analyzed. The results showed that there were 20 GRF genes in M. dodecandrum. Phylogenetic analysis showed that the 71 GRF genes from M. dodecandrum, Arabidopsis thaliana, Camellia sinensis, and Oryza sativa can be divided into three clades and six subclades. The 20 GRF genes of M. dodecandrum were distributed in twelve chromosomes and one contig. Furthermore, the gene structure and motif analysis showed that the intron and motif within each clade were very similar, but there were great differences among different clades. The promoter contained cis-acting elements related to hormone induction, stress, and growth and development. Different transcriptomic expression of MdGRFs indicated that MdGRFs may be involved in regulating the growth and development of M. dodecandrum. The results laid a foundation for further study on the function and molecular mechanism of the M. dodecandrum GRF gene family.

Structure and features of the complete chloroplast genome of Melastoma dodecandrum.

Melastoma dodecandrum, the only creeping species in the Melastoma genus, serves as a medicinal herb in southeast China. It belongs to the huge family Melastomataceae, which contains over 5000 species worldwide. In this study, we used next-generation sequencing to determine the complete chloroplast genome sequences of M. dodecandrum, which is a circular molecule of 156,611 bp in length. After annotation, we identified 131 putative genes in total, comprised of 85 protein-coding genes, 38 transfer RNA genes and 8 ribosomal RNA genes. Genome structure, GC content, repeat sequences and codon usage were investigated to gain a comprehensive understanding of this genome. Furthermore, we conducted comparative genome analyses between the M. dodecandrum genome and that of four other Melastomataceae species. Additionally, a phylogenetic analysis was performed based on available chloroplast genomes of Melastomataceae species and several Myrtaceae species, revealing the taxonomic relationships between M. dodecandrum and related species. In conclusion, our study represents the first look into the complete chloroplast genome of M. dodecandrum, providing abundant information for further studies such as species identification, taxonomy and phylogenetic resolution of Melastomataceae species.

Analysis of Chemical Constituents of Melastoma dodecandrum Lour. by UPLC-ESI-Q-Exactive Focus-MS/MS.

The ethnic drug Melastoma dodecandrum Lour. (MDL) is widely distributed throughout South China, and is the major component of Gong Yan Ping Tablets/Capsules and Zi Di Ning Xue San. Although the pharmacological effects of MDL have been well documented, its chemical profile has not been fully determined. In this study, we have developed a rapid and sensitive UPLC-ESI-Q-Exactive Focus-MS/MS method to characterize the chemical constituents of MDL in the positive and negative ionization modes. A comparison of the chromatographic and spectrometric data obtained using this method with data from databases, the literature and reference standards allowed us to identify or tentatively characterize 109 compounds, including 26 fatty acids, 26 organic acids, 33 flavonoids, six tannins, 10 triterpenoids, two steroids and six other compounds. Notably, 55 of the compounds characterized in this study have never been detected before in this plant. The information obtained in this study therefore enriches our understanding of the chemical composition of MDL and could be used in quality control, pharmacological research and the development of drugs based on MDL. In addition, this study represents the first reported comprehensive analysis of the chemical constituents of MDL.

Structure of a polysaccharide MDP2-1 from Melastoma dodecandrum Lour. and its anti-inflammatory effects.

The anti-inflammatory activity of polysaccharides derived from Melastoma dodecandrum Lour. was evaluated in pyretic mice and HEK-Blue™ hTLR4 cells. The testing led to the identification of MDP2-1, which was then investigated for its structural characteristics and anti-inflammatory effects. Results showed that MDP2-1 had a molecular weight of 29.234 kDa and primarily consisted of galactose, arabinose, rhamnose, glucose, glucuronic acid, and galacturonic acid. Its main backbone was composed of →4)-α-D-GalpA-(1→, →2)-α-L-Rhap-(1→, →3,4)-α-D-GalpA-(1→, →2,4)-α-D-GlcpA-(1→, and its side chains were connected by →4)-α-D-Galp-(1→, α-D-Galp-(1→, →4)-ß-D-Glcp-(1→, and α-L-Araf-(1→. In vivo experiments on mice demonstrated that MDP2-1 attenuated LPS-induced acute lung injury, and in vitro experiments on RAW264.7 cells showed that MDP2-1 reduced the levels of inflammatory mediators and mitigated LPS-induced inflammatory damage by inhibiting the activation of the TLR4 downstream NF-κB/MAPK pathway. These findings suggest that MDP2-1 is a novel anti-inflammatory agent for therapeutic interventions.

DIREN mitigates DSS-induced colitis in mice and attenuates collagen deposition via inhibiting the Wnt/ß-catenin and focal adhesion pathways.

BACKGROUND: DIREN is a SHE ethnic medicine with stasis-resolving, hemostasis, clearing heat, and removing toxin effects. It is clinically used in the treatment of gastrointestinal bleeding, such as ulcerative colitis (UC). AIM OF THE STUDY: Fibrosis is one of the pathological changes in the progression of UC, which can make it challenging to respond to a treatment. We aimed to illuminate the role of DIREN in DSS-induced UC and tried to unveil its related mechanisms from two perspectives: intestinal inflammation and collagen deposition. MATERIALS AND METHODS: A 2.5 % dextran sulfate sodium (DSS) water solution was used to induce colitis in mice. The therapeutic effect of DIREN was assessed using the disease activity index, histopathological score, and colon length. Masson and Sirius Red staining was used to observe the fibrosis in the colon. Apoptosis of colonic epithelial cells was observed by TUNEL immunofluorescence staining. RNA-seq observed differential genes and enrichment pathways. Immunohistochemistry and RT-qPCR were used to detect the expression of molecules related to fibrosis and focal adhesion signaling in colon tissue. RESULTS: The administration of DIREN resulted in a reduction of disease activity index (DAI) in mice with UC while simultaneously promoting an increase in colon length. DIREN mitigated the loss of goblet cells in the colon of UC mice and maintained the integrity of the intestinal mucosa barrier. Masson staining revealed a reduction in colonic fibrosis with DIREN treatment, while Sirius red staining demonstrated a decrease in collagen Ⅰ deposition. DIREN reduced apoptosis of colonic epithelial cells and the expression of genes, such as CDH2, ITGA1, and TGF-ß2. Additionally, the results of GSEA analysis of colon tissue transcriptome showed that the differentially expressed genes were enriched in the focal adhesion pathway. DIREN was found to downregulate the protein expression of BAX, N-cadherin, ß-catenin, Integrin A1, and Vinculin while upregulating the protein expression of BCL2. Additionally, it led to the co-expression of N-cadherin and α-SMA. CONCLUSION: DIREN exerts a protective effect against DSS-induced UC by ameliorating colonic fibrosis via regulation of focal adhesion and the WNT/ß-catenin signaling pathway, thereby inhibiting fibroblast migration and reducing collagen secretion.

Identifying key components from Melastoma dodecandrum in TNF-α-induced osteoblast injury model through a combination of cell membrane chromatography and mass spectrometry.

ETHNOPHARMACOLOGICAL RELEVANCE: Melastoma dodecandrum (MD), a traditional ethnomedicine, has been widely used for the treatment of fractures, osteoarthritis, and osteoporosis due to its remarkable anti-inflammatory activity. However, the specific active components responsible for its therapeutic effects on orthopedic conditions remain unidentified. AIM OF THE STUDY: This study aimed to screen and identify key active components in MD using a combination of cell membrane chromatography and mass spectrometry, followed by cellular validation. MATERIALS AND METHODS: A TNF-α-induced osteoblast injury model and an osteoblast membrane chromatography screening system were established to select and identify chemical components of MD that directly act on osteoblasts. The protective effects of MD on osteoblasts were assessed by evaluating cell viability, alkaline phosphatase (ALP) activity, cell mineralization and the expression of osteogenesis-related proteins OCN, RUNX2, and the TNF-α receptor protein TNFR1. Validation of the activity of individual components was also conducted. RESULTS: MD significantly improved the viability of osteoblasts under TNF-α-induced injury, enhanced ALP activity, stimulated the expression of OCN and RUNX2 proteins, and decreased the expression of TNFR1. Cell membrane chromatography screening identified 32 chemical components, including 21 flavonoids, 6 organic acids, 2 phenylpropanoids, 2 terpenes, and 1 nucleotide. Molecular docking revealed that isovitexin could bind to the specific receptor TNFR1 on the cell membrane. Furthermore, cellular validation demonstrated that isovitexin significantly protected osteoblasts. CONCLUSIONS: MD and its pharmacologically active component, isovitexin, exhibit protective effects against TNF-α-induced inflammatory injury in osteoblasts, laying a solid foundation for future drug development.

Molecular networking-assisted systematical profiling and the in vivo neuroprotective effect of ellagitannins from the Melastoma dodecandrum Lour.

BACKGROUND: Ellagitannins (ETs) are a major classification of natural tannins, with relatively large and complex structures. ETs from medicinal plants are focused increasingly due to urolithins, a kind of intestinal metabolite of ETs, which showed promising anti-Alzheimer's disease (AD) effects. Melastoma dodecandrum (MD), a widely used traditional Chinese medicine is rich in ETs, but their chemistry and potential neuroprotective effects have not been investigated. PURPOSE: This study aimed to identify the chemical composition of ETs in the crude extract of MD and to investigate their neuroprotective effects in vivo. METHODS: UPLC-QTOF-MS-based molecular networking (MN) and structural characterization were applied to targeted profiling of the MD-ETs. Animal behavior experiments, including the novel object recognition test (NOR), open field test (OFT), and Morris water maze test (MWM), were conducted to assess the memory improvement effects of MD-ETs in AD model mice. RESULTS: A total of 70 ETs, ranging from monomers to tetramers, were tracked and characterized in the MD extract using MN-guided targeted profiling, with 59 of them reported for the first time in this species. MD-ETs significantly improved memory impairment in AD mice, as indicated by decreased escape latency, increased number of crossings and target quadrant distance in MWM, increased rearing number in OFT, and increased preference index in NOR. CONCLUSION: This study systematically characterized the composition and structural features of ETs in MD using targeted LC-MS profiling, expanding the chemical information of ETs in MD. Furthermore, the results demonstrate that MD-ETs have significant effects on improving impaired memory in AD mice, suggesting their potential as alternative natural medicines for the treatment of neurodegenerative diseases.

Identification of a novel α-glucosidase inhibitor from Melastoma dodecandrum Lour. fruits and its effect on regulating postprandial blood glucose.

Melastoma dodecandrum Lour. (MDL) extracts have shown potent α-glucosidase inhibitory activity, suggesting MDL might be a good source of α-glucosidase inhibitors. The aim of the study was to identify compounds in MDL extracts with α-glucosidase inhibitory activities and evaluate their effect on postprandial blood glucose as well as elucidating the underlying mechanisms of inhibition. A total of 34 polyphenols were identified in MDL fruits, among which 10 anthocyanins and three proanthocyanidin derivatives were discovered for the first time. Dosing mice with MDL extracts (100 mg/kg body weight, by gavage) was associated with a significantly decrease in postprandial blood glucose concentrations after oral administration of maltose. The most potent α-glucosidase inhibitor was identified as casuarictin (IC50 of 0.21 µg/mL). Casuarictin bound competitively to α-glucosidase, occupying not only the catalytic site but also forming strong hydrogen bonds with α-glucosidase residues. Therefore, casuarictin derived from MDL fruits might be used as novel α-glucosidase inhibitor in functional foods or other dietary products.

Toxicity of Melastoma dodecandrum Lour. and its effects on lipopolysaccharide-induced inflammation and oxidative stress.

Melastoma dodecandrum Lour. (MDL) is component used in traditional Chinese medicine that is widely distributed throughout southern China. MDL has been long utilized in clinical treatment for various conditions, such as inflammation. However, the toxicity and underlying anti-inflammatory mechanism of MDL remain to be elucidated. In the present study, Sprague-Dawley rats received intragastric administration of MDL for 2 months, and the toxicity of MDL was investigated. The rats were treated with lipopolysaccharide (LPS) for 8 h to determine the potential anti-inflammatory mechanism of MDL. The results demonstrated that MDL alone did not affect the expression levels of factors associated with inflammation (IL-1ß, IL-6 and TNF-α) and oxidative stress [malondialdehyde (MDA), superoxide dismutase (SOD) and nitric oxide (NO)] in the rat serum and exerted no effects on rat liver and kidneys. By contrast, MDL attenuated LPS-induced inflammation and oxidative stress by regulating specific cytokines, such as IL-1ß, IL-6, TNF-α, MDA, SOD and NO in the rat serum and alleviated LPS-induced liver and kidney damage. Additionally, compared with the LPS group, MDL inhibited CD4+ T cell differentiation into Th1 and Th17 cells and enhanced CD4+ T cell differentiation into Th2 and Treg cells. MDL also suppressed reactive oxygen species (ROS) production and mitochondrial apoptosis by modulating mitochondrial apoptosis-related proteins in spleen CD4+ T cells. In conclusion, the results of the present study demonstrated the non-toxic nature of MDL and revealed that it alleviated LPS-induced inflammation and oxidative stress by regulating differentiation and ROS production in CD4+ T cells.

The re-sequencing and re-assembly of complete chloroplast genome of Melastoma dodecandrum (Melastomataceae) from Fujian, China.

The plant genus Melastoma of the family Melastomataceae is comprised of nine species and one variety in China. Melastoma dodecandrum is the only creeping species of this genus. Previous study has reported the complete chloroplast genome of M. dodecandrum from Guangzhou, China, but there may be some differences between plant populations from different regions. Herein, we reported the complete chloroplast genome of M. dodecandrum from Fuzhou, China, which was assembled from Pacbio and whole genome data was sequenced. The sequence has a circular molecular length of 156,598 bp and contained 129 genes. Phylogenetic analysis indicated that M. dodecandrum was closely related to M. candidum in Melastomataceae. The study aims to provide insights for the future studies on the differences in molecular evolution level between plant populations of M. dodecandrum and taxonomy of Melastoma.

Chemical constituents from Melastoma dodecandrum and their inhibitory activity on interleukin-8 production in HT-29 cells.

In search of anti-inflammatory lead compounds from traditional Chinese medicines, a bioassay-guided phytochemical study on Melastoma dodecandrum was carried out. As a result, 18 compounds have been isolated. Their chemical structures were determined on the basis of their physicochemical properties and spectral data. Among the isolates, three pentacyclic triterpenoids, ursolic acid (1), asiatic acid (3) and terminolic acid (6), together with one tannin casuarinin (17), were found to significantly decrease interleukin-8 (IL-8) production in human colon cancer cells. The results imply, at least in part, that the anti-inflammatory effect of M. dodecandrum could be due to inhibition of IL-8 production, demonstrated by these naturally occurring compounds described above.

Development and characterization of microsatellite markers for Melastoma dodecandrum (Melastomataceae).

PREMISE OF THE STUDY: Microsatellite markers were developed for Melastoma dodecandrum to investigate the genetic diversity of this species and to detect hybridization and introgression in Melastoma. • METHODS AND RESULTS: Fourteen microsatellite loci were characterized by screening primers developed using two simple sequence repeat (SSR)-enriched libraries. Based on the genotyping of two natural populations, 13 loci were polymorphic and the number of alleles per locus ranged from two to 15. The observed and expected heterozygosities for the 13 loci ranged from 0.235 to 0.941 and 0.219 to 0.922, respectively. Cross-species amplification was successful for all 14 loci in each of two congeneric species, M. candidum and M. sanguineum. • CONCLUSIONS: These polymorphic SSR markers could be used as multilocus molecular makers to study the population genetics of M. dodecandrum, as well as hybridization and introgression among Melastoma species.

Melastoma dodecandrum lour. Protects against cerebral ischemia-reperfusion injury by ameliorating oxidative stress and endoplasmic reticulum stress.

ETHNOPHARMACOLOGICAL RELEVANCE: Melastoma dodecandrum Lour. (MD), a traditional Chinese medicine used by the She ethnic group, has been used to treat cerebral ischemia-reperfusion (CIR) injury due to its efficacy in promoting blood circulation and removing blood stasiss; however, the therapeutic effects and mechanisms of MD in treating CIR injury remain unclear. AIM: To investigate the protective effects of MD on CIR injury, in addition to its impact on oxidative stress, endoplasmic reticulum (ER) stress, and cell apoptosis. MATERIALS AND METHODS: The research was conducted using both cell experiments and animal experiments. The CCK-8 method, immunofluorescence staining, and flow cytometry were used to analyze the effects of MD-containing serum on oxygen-glucose deprivation/reperfusion (OGD/R)-induced PC12 cell viability, reactive oxygen species (ROS) clearance, anti-inflammatory, neuroprotection and inhibition of apoptosis. Furthermore, 2,3,5-Triphenyl tetrazolium chloride staining, hematoxylin and eosin staining, Nissl staining, and immunohistochemistry were used to detect infarct size, pathological changes, Nissl corpuscula and neuronal protein expression in middle cerebral artery occlusion (MCAO) rats. Polymerase chain reaction and Western Blotting were conducted in cell and animal experiments to detect the expression levels of ER stress-related genes and proteins. RESULTS: The MD extract enhanced the viability of PC12 cells under OGD/R modeling, reduced ROS and IL-6 levels, increased MBP levels, and inhibited cell apoptosis. Furthermore, MD improved the infarct area in MCAO rats, increased the number of Nissl bodies, and regulated neuronal protein levels including Microtubule-Associated Protein 2 (MAP-2), Myelin Basic Protein (MBP), Glial Fibrillary Acidic Protein (GFAP), and Neurofilament 200 (NF200). Additionally, MD could regulate the expression levels of oxidative stress proteins malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase (SOD), and catalase (CAT). Both cell and animal experiments demonstrated that MD could inhibit ER stress-related proteins (GRP78, ATF4, ATF6, CHOP) and reduce cell apoptosis. CONCLUSION: This study confirmed that the therapeutic mechanism of the MD extract on CIR injury was via the inhibition of oxidative stress and the ER stress pathway, in addition to the inhibition of apoptosis.