Germacrane-type sesquiterpenes from Pilea cavaleriei Levl. subsp. cavaleriei.

The first systematic investigation of germacrane-type sesquiterpenes from Pilea cavaleriei Levl. subsp. cavaleriei was conducted. Eleven undescribed germacrane analogues named cavalinols A-K were identified. Their planar structures were determined by extensive analysis of 1D and 2D NMR spectroscopic data, and the absolute configurations were further determined by X-ray single crystal diffraction, Mosher method, and time dependent density functional theory (TDDFT) electron circular dichroism (ECD) calculation, with the aid from DFT NMR calculation and NOESY experiment. Except for the common 10-memebered ring, ten new compounds contained a p-coumaroyl sidechain connected to C-8 of the nucleus skeleton. All the isolated compounds were screened for anti-inflammatory activity in LPS stimulated RAW 264.7 cells, and compounds 5 and 6 showed moderate activity.

Three new p-coumaroylated sesquiterpenoids from Pilea cavaleriei.

Four p-coumaroylated sesquiterpenoids (1-4), including three new ones (1, 2, and 4), were isolated from the whole plants of Pilea cavaleriei. Their structures were established on the basis of comprehensive spectroscopic analysis and comparison with data reported in the literature. Compounds 1-4 were evaluated for their antimycobacterial activities, and 2 and 4 were active against Mycobacterium tuberculosis H37Rv with the MIC values of 19.6 ± 0.19 and 17.4 ± 0.12 µg/mL, respectively.

Acclimation to wind loads and/or contact stimuli? A biomechanical study of peltate leaves of Pilea peperomioides.

Plants are exposed to various environmental stresses. Leaves immediately respond to mechano-stimulation, such as wind and touch, by bending and twisting or acclimate over a longer time period by thigmomorphogenetic changes of mechanical and geometrical properties. We selected the peltate leaves of Pilea peperomioides for a comparative analysis of mechano-induced effects on morphology, anatomy, and biomechanics of petiole and transition zone. The plants were cultivated for 6 weeks in a phytochamber divided into four treatment groups: control (no stimulus), touch stimulus (brushing every 30 s), wind stimulus (constant air flow of 4.6 m s-1), and a combination of touch and wind stimuli. Comparing the four treatment groups, neither the petiole nor the transition zone showed significant thigmomorphogenetic acclimations. However, comparing the petiole and the transition zone, the elastic modulus (E), the torsional modulus (G), the E/G ratio, and the axial rigidity (EA) differed significantly, whereas no significant difference was found for the torsional rigidity (GK). The twist-to-bend ratios (EI/GK) of all petioles ranged between 4.33 and 5.99, and of all transition zones between 0.67 and 0.78. Based on the twist-to-bend ratios, we hypothesize that bending loads are accommodated by the petiole, while torsional loads are shared between the transition zone and petiole.

Sesquiterpenoids from Pilea cavaleriei.

One new cis p-coumaroyl copaborneol-type sesquiterpenoid (1), together with its known trans isomer (2) and six other known p-coumaroyl humulane-type sesquiterpenoids (3-8), were isolated from the whole plants of Pilea cavaleriei. Their structures were determined by spectroscopic data. Compounds 1-4 exhibited moderate antimycobacterial activity against Mycobacterium tuberculosis H37Rv.

Petiole-Lamina Transition Zone: A Functionally Crucial but Often Overlooked Leaf Trait.

Although both the petiole and lamina of foliage leaves have been thoroughly studied, the transition zone between them has often been overlooked. We aimed to identify objectively measurable morphological and anatomical criteria for a generally valid definition of the petiole-lamina transition zone by comparing foliage leaves with various body plans (monocotyledons vs. dicotyledons) and spatial arrangements of petiole and lamina (two-dimensional vs. three-dimensional configurations). Cross-sectional geometry and tissue arrangement of petioles and transition zones were investigated via serial thin-sections and µCT. The changes in the cross-sectional geometries from the petiole to the transition zone and the course of the vascular bundles in the transition zone apparently depend on the spatial arrangement, while the arrangement of the vascular bundles in the petioles depends on the body plan. We found an exponential acropetal increase in the cross-sectional area and axial and polar second moments of area to be the defining characteristic of all transition zones studied, regardless of body plan or spatial arrangement. In conclusion, a variety of terms is used in the literature for describing the region between petiole and lamina. We prefer the term "petiole-lamina transition zone" to underline its three-dimensional nature and the integration of multiple gradients of geometry, shape, and size.

Comparative plastid genomics of four Pilea (Urticaceae) species: insight into interspecific plastid genome diversity in Pilea.

BACKGROUND: Pilea is a genus of perennial herbs from the family Urticaceae, and some species are used as courtyard ornamentals or for medicinal purposes. At present, there is no information about the plastid genome of Pilea, which limits our understanding of this genus. Here, we report 4 plastid genomes of Pilea taxa (Pilea mollis, Pilea glauca 'Greizy', Pilea peperomioides and Pilea serpyllacea 'Globosa') and performed comprehensive comparative analysis. RESULTS: The four plastid genomes all have a typical quartile structure. The lengths of the plastid genomes ranged from 150,398 bp to 152,327 bp, and each genome contained 113 unique genes, including 79 protein-coding genes, 4 rRNA genes, and 30 tRNA genes. Comparative analysis showed a rather high level of sequence divergence in the four genomes. Moreover, eight hypervariable regions were identified (petN-psbM, psbZ-trnG-GCC, trnT-UGU-trnL-UAA, accD-psbI, ndhF-rpl32, rpl32-trnL-UAG, ndhA-intron and ycf1), which are proposed for use as DNA barcode regions. Phylogenetic relationships based on the plastid genomes of 23 species of 14 genera of Urticaceae resulted in the placement of Pilea in the middle and lower part of the phylogenetic tree, with 100% bootstrap support within Urticaceae. CONCLUSION: Our results enrich the resources concerning plastid genomes. Comparative plastome analysis provides insight into the interspecific diversity of the plastid genome of Pilea. The identified hypervariable regions could be used for developing molecular markers applicable in various research areas.

Changes in P accumulation, tissue P fractions and acid phosphatase activity of Pilea sinofasciata in poultry manure-impacted soil.

Pilea sinofasciata is a promising phytoextraction material to remove excess phosphorus (P) from manure-impacted soil. However, little information is available on its physiological response to animal manure treatments. Here, P accumulation, tissue P fractions and acid phosphatase activity were investigated in a mining ecotype (ME) and a non-mining ecotype (NME) of P. sinofasciata at different poultry manure (PM) treatments (0, 25, 50, 75, 100 and 125 g kg-1). Biomass and P accumulation of the ME increased up to 50 g kg-1, after which they significantly decreased; while P accumulation of the NME increased up to 100 g kg-1. But, shoot and root P accumulation of the ME were significantly higher than those of the NME at all PM treatments, showing 1.13-2.92 and 1.11-2.89 times higher values, respectively. Inorganic P and nucleic P dominated in tissues of both ecotypes. Besides, the ME maintained higher concentrations of inorganic P and ester P in leaves and ester P, nucleic P and residual P in roots than the NME. Acid phosphatase activity in leaves and roots increased by increasing PM treatments, except in root at 125 g kg-1. Acid phosphatase activity in leaves of the ME was positively correlated with concentrations of inorganic P, ester P and nucleic P, while that of the NME only correlated with inorganic P concentration. Probably, the optimized P fractions allocation and higher tissue acid phosphatase allow the ME to grow well and efficiently accumulate P in PM-impacted soil.

Two new p-coumaroylated sesquiterpenoids from Pilea cavaleriei.

A new p-coumaroylated santalane-type sesquiterpenoid, 8-p-coumaroyl-α-santalene (1), a new p-coumaroylated oplopanane-type sesquiterpenoid, 8-ß-p-coumaroyl-oplopanone (2), and three known p-coumaroylated humulene-type sesquiterpenoids (3-5) were isolated from the ethanol extract of the whole herbs of Pilea cavaleriei. Their structures were elucidated based on the combination of 1D and 2D NMR and HRMS methods. Compound 2 was found to show anti-tuberculosis activity with MIC of 16 µg/ml.

Coexistence via coevolution driven by reduced allelochemical effects and increased tolerance to competition between invasive and native plants.

Coevolution can promote long-term coexistence of two competing species if selection acts to reduce the fitness inequality between competitors and/or strengthen negative frequency dependence within each population. However, clear coevolution between plant competitors has been rarely documented. Plant invasions offer opportunities to capture the process of coevolution. Here we investigated how the developing relationship between an invasive forb, Alliaria petiolata, and a native competitor, Pilea pumila, may affect their long-term coexistence, by testing the competitive effects of populations of varying lengths of co-occurrence on each other across a chronosequence of invasion history. Alliaria petiolata and P. pumila tended to develop greater tolerance to competition over invasion history. Their coexistence was promoted more by increases in stabilizing relative to equalizing processes. These changes likely stem in part from reductions in allelopathic traits in the invader and evolution of tolerance in the native. These results suggested that some native species can evolve tolerance against the competitive effects of strong invaders, which likely promoted their persistence in invaded communities. However, the potential for coevolutionary rescue of competing populations is likely to vary across native species, and evolutionary processes should not be expected to compensate for the ecological consequences of exotic invasions.

Chemical constituents from the whole plants of Pilea cavaleriei Levl subsp. cavaleriei.

Three new sesquiterpene glycosides (1-3), three new glycerol glycosides (4-6), two new alkaloids (7-8), together with seven known compounds (9-15) all of which were isolated from the genus Pilea for the first time, were isolated from the whole plants of Pilea cavaleriei Levl subsp. cavaleriei. Their structures were determined by extensive spectroscopic techniques and chemical methods. The cytotoxic activity of the isolated compounds was evaluated against four cancer cell lines, and none of the tested compounds caused a significant reduction of the cell number.

Chemical constituents of Pilea sinofasciata / 中草药

Objective: To study the chemical constituents of Pilea sinofasciata. Methods: Column chromatography, such as silica gel, Sephadex LH-20, and preparative HPLC, was used to isolate and purify the compounds. Spectroscopic methods like MS, 1H-NMR, and 13C-NMR, and the physical constants were used to elucidate their structures. Results: Nineteen compounds were isolated from 95% ethanol extracts of P. sinofasciata, including α-tocopherol (1), stigmasterol (2), epihernandulcin (3), hernandulcin (4), benzoic acid (5), ethyl linolenate (6), ethyl hexadecanoate (7), α-amyrin (8), palmitic acid (9), behenic acid (10), adenosine (11), indole-3-carboxylic acid (12), protocatechuate (13), gallic acid (14), betulinic acid (15), oleanolic acid (16), potassium nitrate (17), diosmetin 7-O-β-D-glucopyranoside (18), and 3-O-β-D-xylopyranosyl (1→2)-β-D-glucopyranosyl-28-O-β-D-glucopyranosyl oleanolic acid (19). Conclusion: All of the compounds are isolated from the plant for the first time.

Do Pilea Microphylla Improve Sperm DNA Fragmentation and Sperm Parameters in Varicocelized Rats?

Varicocele is one of the most common causes of primary male infertility. Pilea microphylla (PM) is being used as folk medicine. This study was aimed to investigate the effects of PM in a rat model of varicocele. A total of 30 male Wistar rats were divided into control, sham, varicocele, accessory varicocele and PM-treated groups. After 10 weeks of varicocele induction, sperm parameters and chromatin (Aniline blue, acridine orange and toluidine blue) were evaluated, except for the treated and accessory groups that received 50 mg/kg PM orally daily for 10 weeks and then were sacrificed. Sperm parameters significantly decreased in varicocele groups (P < 0.01). Moreover, there was a negative correlation between the DNA fragmentation and sperm parameters in varicocelized rats. Administration of PM led to significantly increased sperm parameters and AO staining (P < 0.05). These findings suggest that PM improves sperm parameters and DNA fragmentation in varicocelized rats. PM can reduce the damage to sperm DNA but not chromatin condensation.

Four new species of Andean Pilea (Urticaceae), with additional notes on the genus in Venezuela.

Four new species of Pilea (Urticaceae) from the Andes of Venezuela are described and illustrated: Pileamatthewii sp. nov., Pileamiguelii sp. nov., Pileanicholasii sp. nov., and Pileanidiae sp. nov. The affinities of these species and their positions within the informal classifications of Pilea proposed by Weddell and Killip are discussed. Notes on other species of Pilea found in Venezuela also are presented.

New phenolic glycosides from Pilea cavaleriei.

Five new phenolic glycosides, 2-hydroxy-(2'E)-prenyl benzoate-2,4'-di-O-ß-D-glucopyranoside (1), 2-hydroxy-(2'E)-prenyl benzoate-2-O-α-L-arabinopyranosyl-(1 → 6)-ß-D-glucopyranoside (2), 4-methylphenol-1-O-α-L-rhamnopyranosyl-(1 → 6)-ß-D-glucopyranoside (3), 4-methylphenol-1-O-α-L-arabinopyranosyl-(1 → 6)-ß-D-glucopyranoside (4), and 3,5-dimethoxyphenol-1-O-ß-D-apiofuranosyl-(1 → 2)-ß-D-glucopyranoside (5), together with six known glycosides (6-11), were isolated from the n-BuOH fraction of the EtOH extract of Pilea cavaleriei Levl subsp. cavaleriei. Their structures were elucidated by extensive spectroscopic analysis, including 1D and 2D NMR spectroscopy as well as HR-ESI-MS, and chemical evidences. All these compounds were isolated from the genus Pilea for the first time.

Antibacterial constituents of Pilea notata C. H. wright / 中国药学杂志

OBJECTIVE: To study the antibacterial constituents of Pilea notata C. H. Wright.

An exotic invader drives the evolution of plant traits that determine mycorrhizal fungal diversity in a native competitor.

The symbiosis between land plants and arbuscular mycorrhizal fungi (AMF) is one of the most widespread and ancient mutualisms on the planet. However, relatively little is known about the evolution of these symbiotic plant-fungal interactions in natural communities. In this study, we investigated the symbiotic AMF communities of populations of the native plant species Pilea pumila (Urticaceae) with varying histories of coexistence with a nonmycorrhizal invasive species, Alliaria petiolata (Brassicaceae), known to affect mycorrhizal communities. We found that native populations of P. pumila with a long history of coexistence with the invasive species developed more diverse symbiotic AMF communities. This effect was strongest when A. petiolata plants were actively growing with the natives, and in soils with the longest history of A. petiolata growth. These results suggest that despite the ancient and widespread nature of the plant-AMF symbiosis, the plant traits responsible for symbiotic preferences can, nevertheless, evolve rapidly in response to environmental changes.

Three new species of Pilea (Urticaceae) from limestone karst in China.

Three hitherto undescribed species of Pilea (Urticaceae) from limestone karst in China are described and illustrated. Affinities of the species are discussed and Global Species Conservation Assessments presented. The new species are Pilea cavernicola A.K. Monro, C.J. Chen & Y.G. Wei, sp. nov. (Vulnerable) which most closely resembles Pilea scripta (Buch.-Ham. ex D.Don) Wedd. and Pilea gracilis Handel-Mazzetti, Pilea shizongensis A.K. Monro, C.J. Chen & Y.G. Wei, sp. nov. (Endangered) which is most similar to Pilea aquarum Dunn and Pilea guizhouensis A.K. Monro, C.J. Chen & Y.G. Wei, sp. nov. (Vulnerable) which resembles Pilea boniana Gagnep. and Pilea rubriflora C. Wright mostclosely.