Terpenoid indole (TIAs) and β-carboline alkaloids (BCAs), such as suppressant reserpine, vasodilatory yohimbine, and antimalarial quinine, are natural compounds derived from strictosidine. These compounds can exert powerful pharmacological effects but be obtained from limited source in nature. the whole biosynthetic pathway of TIAs and BCAs, The Pictet-Spengler reaction catalyzed by strictosidine synthase (STR; EC: 4.3.3.2) is the rate-limiting step. Therefore, it is necessary to investigate their biosynthesis pathways, especially the role of STR, and related findings will support the biosynthetic generation of natural and unnatural compounds. This review summarizes the latest studies concerning the function of STR in TIA and BCA biosynthesis, and illustrates the compounds derived from strictosidine. The substrate specificity of STR based on its structure is also summarized. Proteins that contain six-bladed four-stranded β-propeller folds in many organisms, other than plants, are listed. The presence of these folds may lead to similar functions among organisms. The expression of STR gene can greatly influence the production of many compounds. STR is mainly applied to product various valuable drugs in plant cell suspension culture and biosynthesis in other carriers.
Alkaloids/biosynthesis* ; Carbolines/metabolism* ; Carbon-Nitrogen Lyases ; Indoles/metabolism* ; Terpenes/metabolism*

To study the effects of the extract of fungal elicitor, AgNO3, MeJA and yeast on the growth and content of secondary metabolites of adventitious roots in Tripterygium wilfordii. The above elicitors were supplemented to the medium, the growth and the content of secondary metabolites were measured. When the medium was supplemented with the elicitor Glomerella cingulata or Collectotrichum gloeosporioides, the content of triptolide was increased by 2.24 and 1.93-fold, the alkaloids content was increased by 2.02 and 2.07-fold, respectively. The optimal concentration of G. cingulata was 50 μg/mL for accumulation of triptolide, alkaloids and for the growth of adventitious roots. AgNO3 inhibited the growth of adventitious roots and the accumulation of the alkaloids, whereas it (at 25 μmol/L) increased the accumulation of triptolide by 1.71-fold compared to the control. The growth of adventitious roots, the contents of triptolide and alkaloids were increased 1.04, 1.64 and 2.12-folds, respectively when MeJA was at 50 μmol/L. When the concentration of yeast reached 2 g/L, the content of triptolide increased 1.48-folds. This research demonstrated that supplementation of AgNO3 and yeast enhanced the biosynthesis of triptolide in adventitious roots and the synergism of G. cingulata and MeJA could promote the biosynthesis of both triptolide and alkaloids.
Acetates ; pharmacology ; Alkaloids ; biosynthesis ; Colletotrichum ; Cyclopentanes ; pharmacology ; Diterpenes ; metabolism ; Drugs, Chinese Herbal ; Epoxy Compounds ; metabolism ; Oxylipins ; pharmacology ; Phenanthrenes ; metabolism ; Phyllachorales ; Plant Roots ; drug effects ; growth & development ; Secondary Metabolism ; Tripterygium ; drug effects ; growth & development ; metabolism

To explore the antibacterial activity and mechanism of total alkaloids and berberine from Coptidis Rhizoma on Aeromonas hydrophila, and determine the effect of total alkaloids and berberine from Coptidis Rhizoma on minimum inhibitory concentrations, permeability and fluidity of cell membrane, conformation of membrane proteins and virulence factors of A. hydrophila. The results showed that both total alkaloids and berberine from Coptidis Rhizoma had antibacterial activities on A. hydrophila, with minimum inhibitory concentrations of 62.5 and 125 mg · L(-1), respectively. Total alkaloids and berberine from Coptidis Rhizoma could increase the fluidity of membrane, change the conformation of membrane porteins and increase the permeability of bacteria membrane by 24.52% and 19.66%, respectively. Besides, total alkaloids and berberine from Coptidis Rhizoma significantly decreased the hemolysis of exotoxin and the mRNA expressions of aerA and hlyA (P < 0.05, P < 0.01), the secretion of endotoxin and the mRNA expression of LpxC (P < 0.05, P < 0.01). The results suggested that the antibacterial activity of total alkaloids and berberine from Coptidis Rhizoma on A. hydrophila may be related to the bacteria membrane injury. They inhibited the bacterial growth by increasing membrane lipid fluidity and changing conformation of membrane proteins, and reduced the secretion of virulence factors of A. hydrophila to weaken the pathogenicity.
Aeromonas hydrophila ; drug effects ; genetics ; metabolism ; Alkaloids ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Bacterial Proteins ; genetics ; metabolism ; Bacterial Toxins ; biosynthesis ; Berberine ; pharmacology ; Cell Membrane ; drug effects ; genetics ; metabolism ; Coptis ; chemistry ; Drugs, Chinese Herbal ; pharmacology ; Membrane Fluidity ; drug effects ; Rhizome ; chemistry

Transcription factor is one of the key factors in the regulation of gene expression at the transcriptional level. It plays an important role in plant growth, active components biosynthesis and response to environmental change. This paper summarized the structure and classification of bHLH transcription factors and elaborated the research progress of bHLH transcription factors which regulate the active components in plants, such as flavonoids, alkaloids, and terpenoids. In addition, the possibility of increasing the concentration of active substances by bHLH in medicinal plants was assessed. The paper emphasized great significance of model plants and multidisciplinary research fields including modern genomics, transcriptomics, metabolomics and bioinformatics, providing the contribution to improve the discovery and function characterization of bHLH transcription factors. Accelerating the research in the mechanism of bHLH transcription factors on the regulation of active components biosynthesis will promote the development of breeding and variety improvement of Chinese medicinal materials, also ease the pressure of resources exhaustion of traditional Chinese medicine home and abroad.
Alkaloids ; biosynthesis ; Basic Helix-Loop-Helix Transcription Factors ; chemistry ; classification ; genetics ; metabolism ; Flavonoids ; biosynthesis ; Plants, Medicinal ; genetics ; metabolism ; Terpenes ; metabolism

Atropa belladonna is a medicinal plant and main commercial source of tropane alkaloids (TAs) including scopolamine and hyoscyamine, which are anticholine drugs widely used clinically. Based on the high throughput transcriptome sequencing results, the digital expression patterns of UniGenes representing 9 structural genes (ODC, ADC, AIH, CPA, SPDS, PMT, CYP80F1, H6H, TRII) involved in TAs biosynthesis were constructed, and simultaneously expression analysis of 4 released genes in NCBI (PMT, CYP80F1, H6H, TRII) for verification was performed using qPCR, as well as the TAs contents detection in 8 different tissues. Digital expression patterns results suggested that the 4 genes including ODC, ADC, AIH and CPA involved in the upstream pathway of TAs, and the 2 branch pathway genes including SPDS and TRII were found to be expressed in all the detected tissues with high expression level in secondary root. While the 3 TAs-pathway-specific genes including PMT, CYP80F1, H6H were only expressed in secondary roots and primary roots, mainly in secondary roots. The qPCR detection results of PMT, CYP80F1 and H6H were consistent with the digital expression patterns, but their expression levels in primary root were too low to be detected. The highest content of hyoscyamine was found in tender stems (3.364 mg x g(-1)), followed by tender leaves (1.526 mg x g(-1)), roots (1.598 mg x g(-1)), young fruits (1.271 mg x g(-1)) and fruit sepals (1.413 mg x g(-1)). The highest content of scopolamine was detected in fruit sepals (1.003 mg x g(-1)), then followed by tender stems (0.600 mg x g(-1)) and tender leaves (0.601 mg x g(-1)). Both old stems and old leaves had the lowest content of hyoscyamine and scopolamine. The gene expression profile and TAs accumulation indicated that TAs in Atropa belladonna were mainly biosynthesized in secondary root, and then transported and deposited in tender aerial parts. Screening Atropa belladonna secondary root transcriptome database will facilitate unveiling the unknown enzymatic reactions and the mechanisms of transcriptional control.
Alkaloids ; biosynthesis ; genetics ; metabolism ; Atropa belladonna ; genetics ; metabolism ; Gene Expression Regulation, Plant ; genetics ; Hyoscyamine ; genetics ; metabolism ; Plants, Medicinal ; genetics ; metabolism ; Scopolamine Hydrobromide ; metabolism ; Tropanes ; metabolism

Fungal elicitors are a group of chemicals that can stimulate the secondary metabolite production in plants and microbial cells. After being recognized, it could enhance the expression of related genes through the signal-transduction pathway; regulate the activity of the enzyme involved in the biosynthesis of secondary metabolites. In recent years, the inducible mechanism of fungal elicitors has been studied deeply worldwide. Meanwhile, it has acquired wide concern in the area of biological industry, especially in the fermentation industry. This paper addresses the application and prospect of fungal elicitors in the secondary metabolites of plant and microbial cells.
Alkaloids ; biosynthesis ; genetics ; Camptothecin ; biosynthesis ; Fermentation ; Fungi ; genetics ; metabolism ; Industrial Microbiology ; methods ; Paclitaxel ; biosynthesis ; Plants, Medicinal ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; Secondary Metabolism

OBJECTIVETo evaluate the antimicrobial activity of total alkaloids extracted from Sophorea alopecuroides L. (TASA) against clinical isolated extended-spectrum beta-lactamases (ESBLs) producing Escherichia coli (E. coli) strains.

METHODSThe antibacterial activity of TASA either itself or in combination with cefotaxime (CTX) or ceftazidime (CAZ) was investigated by using the microbroth dilution method and phenotypic confirmatory disk diffusion test against three clinical isolated ESBLs-producing E. coli strains; the interactions of TASA and CTX or CAZ were ascertained by evaluating the fractional inhibitory concentration index (FICI).

RESULTSThe antibacterial activity of either TASA itself or in combination with CTX or CAZ was found. The minimum inhibitory concentration (MICs) of TASA against the ESBLs producing isolates was 12.5 mg/mL. In the combinations with a sub-inhibitory concentration of TASA, a synergistic effect on CTX and CAZ against the ESBLs producing isolates was observed. Similarly, the isolates exposed to lower dose of TASA yielded an increased susceptibility to CTX and CAZ by 8-16 folds determined by microdilution assay. Moreover, enzymatic detection of ESBLs demonstrated that TASA induced reversal resistance to CTX and CAZ partially by a mechanism of inhibition of ESBLs activity in these isolates. Additionally, in the tested isolates following the exposure of TASA, molecular analysis verified the SHV-type beta-lactamase encoding ESBL gene in these isolates, and no mutation was introduced into the ESBL gene.

CONCLUSIONSThese results suggest that TASA could be used as a source of natural compound with pharmacological activity of reversal resistance to antimicrobial agent. These findings also indicated that the application of the TASA in combination with antibiotics might prove useful in the control and treatment of infectious diseases caused by the ESBLs producing enterobacteriaceae.

Alkaloids ; isolation & purification ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Base Sequence ; Cefotaxime ; pharmacology ; Ceftazidime ; pharmacology ; DNA Primers ; Escherichia coli ; drug effects ; enzymology ; Microbial Sensitivity Tests ; Polymerase Chain Reaction ; Sophora ; chemistry ; beta-Lactamases ; biosynthesis

OBJECTIVETo observe matrine-induced erythroid differentiation of K562 cells in relation to activation of the apoptotic pathway in vitro.

METHODSK562 cells were cultured in the presence or absence of matrine at different concentrations for 4 days, and the morphological and ultramicrostructural changes of the cells were observed using inverted microscopy and transmission electron microscopy, respectively. The expression of apoptosis-related protein p27kip1 was detected by immunocytochemistry.

RESULTSCompared to untreated K562 cells, the cells treated with matrine at 0.10 g/L exhibited apoptostic characteristics in the cellular morphology and ultramicrostructure, with the expression of p27kip1 protein upregulated in a concentration- and time-dependent manner.

CONCLUSIONMatrine-induced erythroid differentiation of K562 cells is associated with cell apoptosis, and upregulation of p27kip1 protein expression may play a crucial role in the process of apoptosis.

Alkaloids ; pharmacology ; Antineoplastic Agents, Phytogenic ; pharmacology ; Apoptosis ; drug effects ; physiology ; Cyclin-Dependent Kinase Inhibitor p27 ; biosynthesis ; Dose-Response Relationship, Drug ; Humans ; Immunohistochemistry ; K562 Cells ; Leukemia, Erythroblastic, Acute ; metabolism ; pathology ; Microscopy, Electron, Transmission ; Quinolizines ; pharmacology ; Signal Transduction ; drug effects ; Time Factors

Tropomyosin-related kinase A (TrkA) plays an important role in cell survival, differentiation, and apoptosis in various neuronal and nonneuronal cell types. Here we show that TrkA overexpression by the Tet-On system mimics NGF-mediated activation pathways in the absence of nerve growth factor (NGF) stimulation in U2OS cells. In addition, p53 upregulation upon DNA damage was inhibited by TrkA, and p21 was upregulated by TrkA in a p53-independent manner. TrkA overexpression caused cell death by interrupting cell cycle progression, and TrkA-induced cell death was diminished in the presence of its specific inhibitor GW441756. Interestingly, TrkA-mediated cell death was strongly related to gammaH2AX production and poly (ADP-ribose) polymerase cleavage in the absence of DNA damage inducer. In this study, we also reveal thatgammagammaH2AX production by TrkA is blocked by TrkA kinase inhibitors K-252a and GW441756, and it is also significantly inhibited by JNK inhibitor SP600125. Moreover, reduction of cell viability by TrkA was strongly suppressed by SP600125 treatment, suggesting a critical role of JNK in TrkA-induced cell death. We also found that gammaH2AX and TrkA were colocalized in cytosol in the absence of DNA damage, and the nuclear localization of gammaH2AX induced by DNA damage was partly altered to cytosol by TrkA overexpression. Our results suggest that the abnormal cytosolic accumulation of gammaH2AX is implicated in TrkA-induced cell death in the absence of DNA damage.
Anthracenes/pharmacology ; Apoptosis/drug effects/*genetics ; Carbazoles/pharmacology ; Cell Cycle/drug effects/genetics ; Cell Line, Tumor ; Cyclin-Dependent Kinase Inhibitor p21/*biosynthesis/genetics ; Cytosol/drug effects/enzymology/ultrastructure ; DNA Damage/drug effects/genetics ; Doxorubicin/pharmacology ; Histones/*metabolism ; Humans ; Indole Alkaloids/pharmacology ; MAP Kinase Kinase 4/antagonists & inhibitors ; Nerve Growth Factor/antagonists & inhibitors/metabolism ; Phosphorylation/drug effects ; Protein Binding ; *Protein Transport/drug effects/genetics ; Receptor, trkA/antagonists & inhibitors/*genetics/metabolism ; Signal Transduction ; Transfection

OBJECTIVETo investigate the effects of oxymatrine on the expression of nuclear factor kappa B (NF-kappaB) in the kidneys of rats with adriamycin-induced chronic renal fibrosis.

METHODSTotally 120 Wistar rats were randomly assigned to normal control group, renal fibrosis model group, benazepril treatment group and oxymatrine treatment group (n=30). The rats in the normal control were injected with normal saline via the tail vein, and those in the other 3 groups with adriamycin (2 mg/kg) on the 7th day and 21st day of the experiment, respectively. Oxymatrine (100 mg/kg) or benazepril (6 mg/kg) was given by gastric perfusion after the second injection. Every 4 weeks after the second injection, 5 rats in each group were killed to evaluate the pathological changes and functional impairment of the kidney. Immunohistochemistry was used to detect the expression of NF-kappaB and inhibitory kappa B (IkappaB) in the kidney. The association of NF-kappaB expression with IkappaB expression, renal pathological changes and functional impairment were studied.

RESULTSOxymatrine and benazepril ameliorated renal fibrosis and functional impairment. Immunohistochemical staining revealed increased NF-kappaB expression and decreased IkappaB expression in the model group in comparison with oxymatrine and benazepril treatment groups 8 weeks after the second injection, but no significant difference was noted between the latter two groups. NF-kappaB expression in the kidneys of rats with adriamycin-induced chronic renal fibrosis showed an inverse correlation with IkappaB expression and positive correlation with pathological changes and functional impairment.

CONCLUSIONOxymatrine may inhibit renal fibrosis by down-regulating NF-kappaB expression, which may play a key role in protection against renal fibrosis.

Alkaloids ; pharmacology ; Animals ; Chronic Disease ; Doxorubicin ; Fibrosis ; chemically induced ; I-kappa B Proteins ; biosynthesis ; Immunohistochemistry ; Kidney ; drug effects ; metabolism ; pathology ; Male ; NF-kappa B ; biosynthesis ; Quinolizines ; pharmacology ; Random Allocation ; Rats ; Rats, Wistar