Areca Thirteen Pill Improves Depression in Rat by Modulation of the Chemokine/Chemokine Receptor Axis.

Depressive disorder is a severe and complex mental illness. There are a few anti-depressive medications that can reduce depressive symptoms, but with adverse or side effects. GaoYou-13 (GY-13), commonly known as Areca Thirteen Pill, is a traditional medicine for depression treatment with significant clinical impact. However, the molecular mechanism of GY-13 has not been fully elucidated. This study aimed to explore and explain the action and mechanism of GY-13 in treatment for depression. SD male rats were stimulated differently daily for 42 days to construct a depression rat model and divided into six groups: the control, CUMS model, GY-13L, GY-13 M, GY-13H, and FLUO. The body weight of was measured on day 7, 14, 21, 28, 35, and 42 or different days, and the behavioral tests (Open-field test, Sucrose preference test, Morris water maze) were made alongside. After the rats were decapitated, the rat brains were stained with Nissl or H&E dyes. The serums of TNF-α and IL-1ß were tested. The protein of p-IKKα, p-IкBα, and p-NFкBp65 was traced. Then nano-LC-MS/MS analysis was made to detect the mechanism of GY-13. The active ingredients, drug targets, and key pathways of GY-13 in treating depression were analyzed through network pharmacology and molecular docking. With immunohistochemistry, quantitative RT-PCR, and western-blot techniques, the therapeutic mechanism of GY-13 was traced and analyzed. This study revealed that GY-13 significantly enhances autonomous and exploratory behavior, sucrose consumption, learning and memory ability, and hippocampal neuronal degeneration, which inhibits inflammation. In addition, omics analysis showed several proteins were altered in the hippocampus of rats following CUMS and GY-13 treatment. Bioinformatics analysis and network pharmacology revealed the antidepressant effects of GY-13 are related to the chemokine/chemokine receptor axis. Immunohistochemistry, western blotting and RT-PCR assay further support the findings of omics analysis. We highlighted the importance of the chemokine/chemokine receptor axis in the treatment of depression, as well as showed GY-13 can be used as a novel targeted therapy for depression treatment.

Insights into Adaptive Regulation of the Leaf-Petiole System: Strategies for Survival of Water Lily Plants under Salt Stress.

The water lily (Nymphaea tetragona) is an ancient angiosperm that belongs to the Nymphaeaceae family. As a rooted floating-leaf plant, water lilies are generally cultivated in fresh water, therefore, little is known about their survival strategies under salt stress. Long-term salt stress causes morphological changes, such as the rapid regeneration of floating leaves and a significant decrease in leaf number and surface area. We demonstrate that salt stress induces toxicity soon after treatment, but plants can adapt by regenerating floating leaves that are photosynthetically active. Transcriptome profiling revealed that ion binding was one of the most-enriched GO terms in leaf-petiole systems under salt stress. Sodium-transporter-related genes were downregulated, whereas K+ transporter genes were both up- and downregulated. These results suggest that restricting intracellular Na+ importing while maintaining balanced K+ homeostasis is an adaptive strategy for tolerating long-term salt stress. ICP-MS analysis identified the petioles and leaves as Na-hyperaccumulators, with a maximum content of over 80 g kg-1 DW under salt stress. Mapping of the Na-hyperaccumulation trait onto the phylogenetic relationships revealed that water lily plants might have a long evolutionary history from ancient marine plants, or may have undergone historical ecological events from salt to fresh water. Ammonium transporter genes involved in nitrogen metabolism were downregulated, whereas NO3--related transporters were upregulated in both the leaves and petioles, suggesting a selective bias toward NO3- uptake under salt stress. The morphological changes we observed may be due to the reduced expression of genes related to auxin signal transduction. In conclusion, the floating leaves and submerged petioles of the water lily use a series of adaptive strategies to survive salt stress. These include the absorption and transport of ions and nutrients from the surrounding environments, and the ability to hyperaccumulate Na+. These adaptations may serve as the physiological basis for salt tolerance in water lily plants.

Co-exposure of sulfur nanoparticles and Cu alleviate Cu stress and toxicity to oilseed rape Brassica napus L.

Experiments were performed to explore the impact of sulfur nanoparticles (SNPs) on growth, Cu accumulation, and physiological and biochemical responses of oilseed rape (Brassica napus L.) inoculated with 5 mg/L Cu-amended MS medium supplemented with or without 300 mg/L SNPs exposure. Cu exerted severe phytotoxicity and inhibited plant growth. SNPs application enhanced the shoot height, root length, and dry weight of shoot and root by 34.6%, 282%, 41.7% and 37.1%, respectively, over Cu treatment alone, while the shoot and root Cu contents and Cu-induced lipid perodixation as the malondialdehyde (MDA) levels in shoots and roots were decreased by 37.6%, 35%, 28.4% and 26.8%. Further, the increases in superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR) and glutathione S-transferase (GST) enzyme activities caused by Cu stress were mitigated in shoots (10.9%-37.1%) and roots (14.6%-35.3%) with SNPs addition. SNPs also positively counteracted the negative effects on shoot K, Ca, P, Mg, Mn, Zn and Fe contents and root K, Ca, Mg and Mn contents from Cu exposure alone, and significantly promoted the nutrients accumulation in plant. Additionally, in comparison with common bulk sulfur particles (BSPs) and sulfate, SNPs showed more positive effects on promoting growth in shoots (6.7% and 19.5%) and roots (10.9% and 15.1%), as well as lowering the shoot Cu content (40.1% and 43.3%) under Cu stress. Thus, SNPs application has potential to be a green and sustainable technology for increasing plant productivity and reducing accumulation of toxic metals in heavy metal polluted soils.

Mongolian Medicine Areca Thirteen Pill (GY-13) Improved Depressive Syndrome via upregulating cAMP/PKA/CREB/BDNF signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Areca Thirteen Pill, also called Gao You-13 (GY-13), is a traditional Mongolian herbal formula and has been extensively used to treat depression in Mongolian areas, which belongs to Heyi disease in Mongolian medicine. Major depressive disorder is a serious psychiatric disease, only one-third of individuals with depression are responsive to current antidepressants in clinic. Growing attention has been attracted by traditional herbal medicines in fighting depression because they are considered safer alternatives to pharmacotherapy. AIM OF THE STUDY: To reveal the mechanism of GY-13 in the treatment of depression. MATERIALS AND METHODS: The rat depression model was established by chronic unpredictable mild stress (CUMS), and primary hippocampal neurons were used to construct a glutamate-induced excitotoxicity model. The antidepressant effect of GY-13 was then assessed by performing sucrose preference tests, open field tests, and body weight measurements on rats. The expression of cAMP and PKA, mRNA levels of brain-derived neurotrophic factor (BDNF) and cAMP response element binding protein (CREB), and hippocampal neuronal apoptosis were measured. RESULTS: The results indicate that GY-13 significantly improves depression-like behavior, rescues decreased cAMP， PKA, recovers the mRNA levels of CREB and BDNF, and increases the proliferative activity of hippocampus. In addition, blockade of PKA reverses the effects of GY-13 treatment on CREB mRNA, BDNF mRNA levels. In vitro, GY-13 treatment increased hippocampal proliferative activity and attenuated Glu-induced apoptosis of hippocampal neurons as well as reduced CREB mRNA and BDNF mRNA expression levels. CONCLUSIONS: Our research demonstrated that GY-13 treatment exerted a potent antidepressant action via activation of cAMP/CREB/BDNF signaling pathway, promoting proliferation, and suppressing apoptosis. This research provides molecular biological ground for developing GY-13 into a potent alternative for the intervention of depression.

Anshen Buxin Liuwei Pill, a Mongolian Medicinal Formula, Could Protect H2O2-Induced H9c2 Myocardial Cell Injury by Suppressing Apoptosis, Calcium Channel Activation, and Oxidative Stress.

BACKGROUND: Anshen Buxin Liuwei pill (ABLP) is a Mongolian medicinal formula which has a therapeutic effect on the symptoms such as coronary heart disease, angina pectoris, arrhythmia, depression and irritability, palpitation, and short breath. However, its bioactivity against cardiac injury remains unclear. METHODS: The protective effect of ABLP was evaluated using H9c2 cells. Cell viability, intracellular Ca2+, reactive oxidative indices, and mitochondrial membrane potential (∆ψ) were assessed, respectively. The mRNA levels of Ca2+ channel-related genes (DHPR, RyR2, and SCN5A) and oxidative stress-related genes (Keap1, Nrf2, and HO-1) were measured by RT-PCR. RESULTS: 0.5-50 µg/mL ABLP could significantly decrease H2O2-induced cell injury by suppressing cell necrosis/apoptosis and excess oxidative stress, ameliorating the collapse of ∆ψ, and reducing intracellular Ca2+ concentration. Furthermore, 0.5-50 µg/mL ABLP reversed H2O2-induced imbalance in the mRNA levels of DHPR, RyR2, SCN5A, Keap1, Nrf2, and HO-1 gene in H9c2 cells, which further illustrate the mechanism. CONCLUSION: ABLP provided protective and therapeutic benefits against H2O2-induced H9c2 cell injury, indicating that this formula can effectively treat coronary disease. In addition, the present study also provides an in-depth understanding of the pharmacological functions of ABLP, which may lead to further successful applications of Mongolian medicine.

Anshen-Buxin-Liuwei pill, a Mongolian medicinal formula could alleviate cardiomyocyte hypoxia/reoxygenation injury via mitochondrion pathway.

BACKGROUND: Anshen Buxin Liuwei pill (ABLP) is a Mongolian medicinal formula that is composed of six medicinal materials: the Mongolian medicine Bos taurus domesticus Gmelin, Choerospondias axillaris (Roxb.) Burtt et Hill, Myristica fragrans Houtt., Eugenia caryophµllata Thunb., Aucklandia lappa Decne., and Liqui dambar formosana Hance. ABLP is considered to have a therapeutic effect on symptoms such as coronary heart disease, angina pectoris, arrhythmia, depression and irritability, palpitation, and shortness of breath. METHODS: H9c2 cardiomyocytes were used to construct a hypoxia/reoxygenation (HR) injury model. CCK-8 assay and Annexin V-FITC cell apoptosis assays were used for cell viability and cell apoptosis determination. The LDH, SOD, MDA, CAT, CK, GSH-Px, Na+-K+-ATPase, and Ca2+-ATPase activities in cells were determined to assess the protective effects of ABLP. The mRNA levels of Sirtuin3 (Sirt3) and Cytochrome C (Cytc) in H9c2 cells were determined by quantitative real-time PCR. RESULTS: The results indicate that HR-treated cells began to shrink from the spindle in an irregular shape with some floated in the medium. By increasing the therapeutic dose of ABLP (5, 25, and 50 µg/mL), the cells gradually reconverted in a concentration-dependent manner. The release of CK in HR-treated cells was significantly increased, indicating that ABLP exerts a protective effect in H9c2 cells against HR injury and can improve mitochondrial energy metabolism and mitochondrial function integrity. The present study scrutinized the cardioprotective effects of ABLP against HR-induced H9c2 cell injury through antioxidant and mitochondrial pathways. CONCLUSIONS: ABLP could be a promising therapeutic drug for the treatment of myocardial ischemic cardiovascular disease. The results will provide reasonable information for the clinical use of ABLP.

Transcriptomic Characterization of Nitrate-Enhanced Stevioside Glycoside Synthesis in Stevia (Stevia rebaudiana) Bertoni.

Nitrogen forms (nitrate (NO3-) or ammonium (NH4+)) are vital to plant growth and metabolism. In stevia (Stevia rebaudiana), it is important to assess whether nitrogen forms can influence the synthesis of the high-value terpene metabolites-steviol glycosides (SGs), together with the underlying mechanisms. Field and pot experiments were performed where stevia plants were fertilized with either NO3- or NH4+ nutrition to the same level of nitrogen. Physiological measurements suggested that nitrogen forms had no significant impact on biomass and the total nitrogen content of stevia leaves, but NO3--enhanced leaf SGs contents. Transcriptomic analysis identified 397 genes that were differentially expressed (DEGs) between NO3- and NH4+ treatments. Assessment of the DEGs highlighted the responses in secondary metabolism, particularly in terpenoid metabolism, to nitrogen forms. Further examinations of the expression patterns of SGs synthesis-related genes and potential transcription factors suggested that GGPPS and CPS genes, as well as the WRKY and MYB transcription factors, could be driving N form-regulated SG synthesis. We concluded that NO3-, rather than NH4+, can promote leaf SG synthesis via the NO3--MYB/WRKY-GGPPS/CPS module. Our study suggests that insights into the molecular mechanism of how SG synthesis can be affected by nitrogen forms.

Comparative transcriptome analysis provides insights into steviol glycoside synthesis in stevia (Stevia rebaudiana Bertoni) leaves under nitrogen deficiency.

KEY MESSAGE: Transcriptome analysis revealed the potential mechanism of nitrogen regulating steviol glycosides synthesis via shifting of leaf carbon metabolic flux or inducing certain transcription factors. Nitrogen (N) plays key regulatory roles in both stevia (Stevia rebaudiana) growth and the synthesis of its functional metabolite steviol glycosides (SGs), but the mechanism by which this nutrient regulates SGs synthesis remains to be elucidated. To address this question, a pot experiment was performed in a greenhouse where stevia plants fertilized with N (the control as CK plants) and compared with plants without the supply of N. Physiological and biochemical analyses were conducted to test the growth and metabolic responses of plants to N regimes. Our results showed that N deficiency significantly inhibited plant growth and leaf photosynthesis, while increased leaf SGs contents in stevia (49.97, 46.64 and 84.80% respectively for rebaudioside A, stevioside, and rebaudioside C), which may be partly due to "concentration effect". Then, transcriptome analysis was conducted to understand the underlying mechanisms. A total of 535 differentially expressed genes were identified, and carbon metabolism-related events were highlighted by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Many of these genes were significantly upregulated by N-deficiency, including those involved in "phenylpropanoid biosynthesis", "flavonoid biosynthesis" and "starch and sucrose metabolism". Our study also analyzed the expression patterns of SGs synthesis-related genes under two N regimes and the potential transcription factors linking N nutrition and SG metabolism. N-deficiency may promote SGs synthesis by changing the carbon metabolism flux or inducing certain transcription factors. Our results provide deeper insight into the relationship between N nutrition and SGs synthesis in stevia plants.

The chromosome-level Stevia genome provides insights into steviol glycoside biosynthesis.

Stevia (Stevia rebaudiana Bertoni) is well known for its very sweet steviol glycosides (SGs) consisting of a common tetracyclic diterpenoid steviol backbone and a variable glycone. Steviol glycosides are 150-300 times sweeter than sucrose and are used as natural zero-calorie sweeteners. However, the most promising compounds are biosynthesized in small amounts. Based on Illumina, PacBio, and Hi-C sequencing, we constructed a chromosome-level assembly of Stevia covering 1416 Mb with a contig N50 value of 616.85 kb and a scaffold N50 value of 106.55 Mb. More than four-fifths of the Stevia genome consisted of repetitive elements. We annotated 44,143 high-confidence protein-coding genes in the high-quality genome. Genome evolution analysis suggested that Stevia and sunflower diverged ~29.4 million years ago (Mya), shortly after the whole-genome duplication (WGD) event (WGD-2, ~32.1 Mya) that occurred in their common ancestor. Comparative genomic analysis revealed that the expanded genes in Stevia were mainly enriched for biosynthesis of specialized metabolites, especially biosynthesis of terpenoid backbones, and for further oxidation and glycosylation of these compounds. We further identified all candidate genes involved in SG biosynthesis. Collectively, our current findings on the Stevia reference genome will be very helpful for dissecting the evolutionary history of Stevia and for discovering novel genes contributing to SG biosynthesis and other important agronomic traits in future breeding programs.

Selection and validation of appropriate reference genes for RT-qPCR analysis of flowering stages and different genotypes of Iris germanica L.

Iris germanica L. is a perennial herbaceous plant that has been widely cultivated worldwide and is popular for its elegant and vibrantly colorful flowers. Selection of appropriate reference genes is the prerequisite for accurate normalization of target gene expression by quantitative real-time PCR. However, to date, the most suitable reference genes for flowering stages have not been elucidated in I. germanica. In this study, eight candidate reference genes were examined for the normalization of RT-qPCR in three I. germanica cultivars, and their stability were evaluated by four different algorithms (GeNorm, NormFinder, BestKeeper, and Ref-finder). The results revealed that IgUBC and IgGAPDH were the most stable reference genes in '00246' and 'Elizabeth', and IgTUB and IgUBC showed stable expression in '2010200'. IgUBC and IgGAPDH were the most stable in all samples, while IgUBQ showed the least stability. Finally, to validate the reliability of the selected reference genes, the expression patterns of IgFT (Flowering Locus T gene) was analyzed and emphasized the importance of appropriate reference gene selection. This work presented the first systematic study of reference genes selection during flower bud development and provided guidance to research of the molecular mechanisms of flowering stages in I. germanica.

The complete chloroplast genome of Stemona tuberosa Lour (Stemonaceae).

Stemona tuberosa Lour is a perennial herb in the family of Stemonaceae. It is commonly used as traditional medicine in China. Here, we assembled and annotated the complete chloroplast genome of S. tuberosa. The chloroplast genome was 154,374 bp in length, containing a typical quadripartite structure with a large single copy (LSC) of 82,305 bp, a small single copy (SSC) of 17,929 bp, and two inverted repeats (IRa and IRb) regions of 27,070 bp each. The overall GC content of the genome was 37.88%. A total of 134 genes were annotated in the chloroplast genome, including 88 protein-coding genes, 38 transfer RNA (tRNA) genes, and 8 ribosomal RNA (rRNA) genes. Phylogenetic analysis suggested that S. tuberosa was closely related to S. japonica and S. mairei.

Systems pharmacology-based dissection of mechanisms of Tibetan medicinal compound Ruteng as an effective treatment for collagen-induced arthritis rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Compound Ruteng (CRT) is a prescribed formulation based on the theory of Tibetan medicine for the treatment of yellow-water-disease. It is consisted with 7 medicinal material include Boswellia carterii Birdw (named "Ruxiang" in Chinese); Tinospora sinensis (Lour.) Merr. (named "Kuan-Jin-Teng" in Chinese), Cassia obtusifolia L (named "Jue-Ming-Zi" in Chinese); Abelmoschus manihot (L.) Medic (named "Huang-Kui-Zi" in Chinese); Terminalia chebula Retz. (named "He-Zi" in Chinese); Lamiophlomis rotata (Benth.) Kudo (named "Du-Yi-Wei" in Chinese) and Pyrethrum tatsienense (Bur. et Franch.) Ling (named "Da-Jian-Ju" in Chinese). They are widely distributed in Tibet area of China and have been used to treat rheumatism, jaundice, and skin diseases for centuries. AIM OF THE STUDY: The present study was conducted to investigate the anti-arthritis effect of CRT and to disclose the systems pharmacology-based dissection of mechanisms. MATERIALS AND METHODS: The chemical constituents in CRT were identified using HPLC method, and CRT candidate targets against RA were screened by network pharmacology-based analysis and further experimentally validated based on collagen-induced arthritis (CIA) rat model. Furthermore, therapeutic mechanisms and pathways of CRT were investigated. RESULTS: 391 potential targets (protein) were predicted against 92 active ingredients of 7 medicinal materials in CRT. Enrichment analysis and molecular docking studies also enforced the practiced results. X-ray based physiological imaging showed the attenuated effect of CRT on paw swelling, synovial joints and cartilage with improved inflammation in CIA rats. Moreover, the expression of biomarkers associated with RA such as MMP1, MMP3 and MMP13 and TNF-a, COX2 and iNOS are down-regulated in ankle joints, serum, or liver. CONCLUSION: In conclusion, CRT compound could attenuate RA symptoms and active ingredients of this compound could be considered for drug designing to treat RA.

The complete chloroplast genome of Polygonatum cirrhifolium (Wall.) Royle, a medicine herb.

Polygonatum cirrhifolium (Wall.) Royle is a medicinal plant of commercial value. In the present study, we assembled the complete chloroplast genome of P. cirrhifolium. The total genome was a circular DNA molecule of 155,583 bp, which was made up of a large single copy region (84,412 bp), a small single copy region (18,427 bp), and a pair of inverted repeat regions (26,372 bp each). A total of 133 genes was annotated in the chloroplast genome, including 85 protein-coding genes, 40 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes. Overall, the chloroplast genome had a GC content of 37.66%. Phylogenetic analysis showed that P. cirrhifolium was closely related to P. kingianum.

Identification of GH1 gene family fgt members in Stevia rebaudiana and their expression when grown in darkness.

Stevia rebaudiana Bertoni is an important economic crop that is well known for its secondary metabolites, steviol glycosides (SGs), found in leaves. Because the enzymes of deglycosylation (glycoside hydrolases) play important roles in SGs biosynthetic processes, our study is focused on the functions of ß-glucosidases in SGs catabolism in stevia. We cloned and characterized 19 stevia GH1 genes based on transcriptomic sequences. The 19 genes were divided into five putative subfamilies in Arabidopsis. Conserved motifs in the SrGH1 proteins were analysed using the online motif-based sequence analysis tool, MEME. Most of the identified proteins contain the conserved 'TFNEP' motif (contains the catalytic acid/base) and 'ITENG' motif (contains the catalytic nucleophile). Furthermore, the steviol glycoside content and expression of these 19 genes were characterized under constant darkness. The dark treatment lowered the steviol glycoside content significantly, while SrBGLU16 responded to darkness and was markedly upregulated. This study is the first transcriptome-wide analysis of the GH1 family in Stevia rebaudiana. The sequences of 19 SrGH1 members and their expression when grown in darkness were characterized. Among the 19 genes, SrBGLU16 was markedly upregulated by darkness. Thus, we identified SrBGLU16 for further investigation as a possible steviol glycoside beta-glucosidase.

Liquiritin, a novel inhibitor of TRPV1 and TRPA1, protects against LPS-induced acute lung injury.

TRPV1 and TRPA1 are cation channels that play key roles in inflammatory signaling pathways. They are co-expressed on airway C-fibers, where they exert synergistic effects on causing inflammation and cough. Licorice, the root of Glycyrrhiza uralensis, has been widely used in China as an anti-inflammatory and anti-coughing herb. To learn if TRPV1 and TRPA1 might be key targets of the anti-inflammatory and antitussive effects of licorice, we examined liquiritin, the main flavonoid compound and active ingredient of licorice, on agonist-evoked TRPV1 and TRPA1 activation. Liquiritin inhibited capsaicin- and allyl isothiocyanate-evoked TRPV1 and TRPA1 whole-cell currents, respectively, with a similar potency and maximal inhibition. In a mouse acute lung injury (ALI) model induced by the bacterial endotoxin lipopolysaccharide, which involves both TRPV1 and TRPA1, an oral gavage of liquiritin prevented tissue damage and suppressed inflammation and the activation of NF-κB signaling pathway in the lung tissue. Liquiritin also suppressed LPS-induced increase in TRPV1 and TRPA1 protein expression in the lung tissue, as well as TRPV1 and TRPA1 mRNA levels in cells contained in mouse bronchoalveolar lavage fluid. In cultured THP-1 monocytes, liguiritin, or TRPV1 and TRPA1 antagonists capsazepine and HC030031, respectively, diminished not only cytokine-induced upregulation of NF-κB function but also TRPV1 and TRPA1 expression at both protein and mRNA levels. We conclude that the anti-inflammatory and antitussive effects of liquiritin are mediated by the dual inhibition of TRPV1 and TRPA1 channels, which are upregulated in nonneuronal cells through the NF-κB pathway during airway inflammation via a positive feedback mechanism.

The complete chloroplast genome of Hosta plantaginea (Lam.) Aschers.

Hosta plantaginea is an important ornamental and horticultural plant endemic to China. In this study, we generated complete chloroplast genome of H. plantaginea using high-throughput sequencing. The complete chloroplast sequence is a circular molecule of 157,091 bp in size, consisting of a large single copy (LSC, 86,061 bp) and a small single copy (SSC; 18,282 bp) separated by a pair of inverted repeats (IRs; 26,374 bp), The total GC content is 37.8%, with 35.9, 31.7, and 43.0% in LSC, SSC, and IRs, respectively. A total of 132 genes are annotated, including 84 protein-coding genes, 38 tRNAs, 8 rRNAs, and 2 pseudogenes. The phylogenetic analysis revealed that H. plantaginea was formed to be the early diverging species within Hosta.

Nitrogen drives plant growth to the detriment of leaf sugar and steviol glycosides metabolisms in Stevia (Stevia rebaudiana Bertoni).

Steviol glycosides (SGs) in Stevia (Stevia rebaudiana Bertoni) leaves are important due to their high sweetness and low calorific value. The yield of SGs is dependent on fertilization regimes, but the relationship between nitrogen (N) administration and SGs synthesis is still unclear. In this study, we investigate the effects of N rates on SGs production through hydroponic and plot experiments. The SGs yield was not significantly changed by N fertilization, but leaf SGs concentrations were significantly reduced due to the "dilution effect". Additionally, N addition decreased leaf carbon (C)/N ratio and soluble sugar concentration, accompanied with the inhibited phosphoenolpyruvate carboxylase and L-phenylalanine ammonia_lyase activities. A significant positive correlation between leaf SGs concentrations, C/N ratio and soluble sugar concentration was observed. Overall, we suggest that N-driven Stevia growth negatively affects SGs concentrations. The leaf C/N ratio and soluble sugar changes indicated the occurrence of metabolic reprogramming.

Characterisation of the complete chloroplast genome of Lycoris longituba (Amaryllidaceae).

Lycoris longituba is a species in the Amaryllidaceae with high ornamental and medicinal value. It is also an endangered species in East China due to the narrow distribution. Here, we assembled and characterised the complete chloroplast (cp) genome of this species using high throughput sequencing and bioinformatics analysis. As a result, the whole cp genome size is 158,484 bp, including two inverted repeat (IR) regions of 26,765 bp, large single-copy region (LSC) of 86,458 bp and small single-copy region (SSC) of 18,496 bp. A total of 137 genes were identified, including 87 protein-coding genes, 42 tRNA genes, and eight rRNA genes. Phylogenomic analysis was carried out using complete cp genome of 18 species in five families, supporting the closer relationship between L. longituba and L. squamigera than L. radiata and L. sprengeri in Amaryllidaceae.

Sweroside Alleviated Aconitine-Induced Cardiac Toxicity in H9c2 Cardiomyoblast Cell Line.

Aconitine is the main bioactive ingredient of Aconitum plants, which are well-known botanical herbs in China. Aconitine is also notorious for its high cardiotoxicity, as it can induce life-threatening ventricular arrhythmias. Unfortunately, there are few effective antidotes to aconitine toxicity. This study aimed to evaluate the potent protective effects of the ingredients from V. baillonii on aconitine toxicity on H9c2 cell line. Cell viability was assessed by methylthiazoltetrazolium bromide (MTT). Intracellular Ca2+ concentration alteration and reactive oxygen species (ROS) generation were observed by confocal microscopy and flow cytometry, respectively. Cellular oxidative stress was analyzed by measuring malondialdehyde (MDA) and superoxide dismutase (SOD) levels. Mitochondrial membrane potential (ΔΨ) was determined using JC-1 kit. RT-PCR and Hoechst staining techniques were conducted to determine the levels of autophagy/apoptosis. The mRNA levels of dihydropyridine receptor (DHPR), ryanodine receptors (RyR2) and sarcoplasmic reticulum Ca2+-ATPase (SERCA) were measured by RT-PCR. We screened six components from V. baillonii, among which, sweroside exhibited the strongest protective effects on aconitine-induced cardiac toxicity. Sweroside suppressed the aconitine-induced mRNA expressions of NaV1.5 (encoded by SCN5A), RyR2 and DHPR, and reversed the aconitine-induced decrease in mRNA level of SERCA, thus preventing the aconitine-induced persistent intracellular Ca2+ accumulation and avoiding intracellular Ca2+ overload. We further found that sweroside restabilized the aconitine-disrupted mitochondrial membrane potential (ΔΨ) and reversed the aconitine-induced increase in the mRNA levels of cell autophagy-related factors (Beclin-1, Caspase-3, and LC3- II) in H9c2 cells. In the whole-animal experiments, we observed that sweroside (50 mg/kg) alleviated effectively aconitine-induced arrhythmias by analysis of electrocardiogram (ECG) recording in rats. Our results demonstrate that sweroside may protect cardiomyocytes from aconitine toxicity by maintaining intracellular Ca2+ homeostasis, restabilizing mitochondrial membrane potential (ΔΨ) and avoiding cell autophagy/apoptosis.