Curcumin attenuates allergic airway inflammation by regulation of CD4+CD25+ regulatory T cells (Tregs)/Th17 balance in ovalbumin-sensitized mice

The present study aimed to determine the protective effects and the underlying mechanisms of curcumin on ovalbumin (OVA)-induced allergic inflammation in a mouse model of allergic asthma. Asthma mice model was established by ovalbumin. A total of 60 mice were randomly assigned to six experimental groups: control, model, dexamethasone (2 mg/kg), and curcumin (50 mg/kg, 100 mg/kg, 200 mg/kg). Airway resistance (Raw) was measured by the forced oscillation technique, differential cell count in BAL fluid (BALF) was measured by Wright–Giemsa staining, histological assessment was measured by hematoxylin and eosin (HE) staining, BALF levels of Treg/Th17 cytokines were measured by enzyme-linked immunosorbent assay, Treg cells and Th17 cells were evaluated by flow cytometry (FCM). Our study demonstrated that curcumin inhibited OVA-induced increases in eosinophil count; interleukin (IL)-17A level were recovered in bronchoalveolar lavage fluid increased IL-10 level in bronchoalveolar lavage fluid. Histological studies demonstrated that curcumin substantially inhibited OVA-induced eosinophilia in lung tissue. Flow cytometry (FCM) studies demonstrated that curcumin remarkably inhibited Th17 cells and significantly increased Treg cells. The results in vivo show ovalbumin-induced significantly broke Treg/Th17 balance; curcumin treatments markedly attenuated the inflammatory in asthma model by regulating Treg/Th17 balance. Our findings support the possible use of curcumin as a therapeutic drug for patients with allergic asthma.     

Apigenin protects ovalbumin-induced asthma through the regulation of Th17 cells

The aim of the study was to investigate the anti-asthmatic effects of apigenin and the possible mechanisms. Asthma model was established by ovalbumin-induced asthma. A total of 50 mice were randomly assigned to six experimental groups: control, model, dexamethasone (2 mg/kg) and apigenin (5 mg/kg, 10 mg/kg). Airway resistance (Raw) was measured, histological studies were evaluated by hematoxylin and eosin (HE) staining, OVA-specific serum and BALF IgE levels and Th17 cytokines were evaluated by enzyme-linked immunosorbent assay (ELISA), Th17 cells were evaluated by flow cytometry (FCM), and protein level of RORγt was measured by western blotting. Our study demonstrated that apigenin inhibited OVA-induced increases in Raw and eosinophil count; interleukin (IL)-6, TNF-ɑ and IL-17A levels were recovered. Histological studies demonstrated that apigenin substantially inhibited OVA-induced eosinophilia in lung tissue and airway tissue. Flow cytometry studies demonstrated that apigenin substantially inhibited Th17 cells. Western blotting studies demonstrated that apigenin substantially inhibited RORγt protein level. These findings suggest that apigenin may effectively ameliorate the progression of asthma and could be used as a therapy for patients with allergic asthma.     

Anti-asthmatic effects of matrine in a mouse model of allergic asthma

The aim of the study was to investigate the anti-asthmatic effects of matrine and the possible mechanisms. Asthma model was established by ovalbumin-induced. A total of 50 mice were randomly assigned to five experimental groups: control, model, dexamethasone (2 mg/kg) and matrine (50 mg/kg, 100 mg/kg). Airway resistance (Raw) was measured, histological studies were evaluated by the hematoxylin and eosin (HE) staining, interleukin-4 (IL-4) and interleukin-13 were evaluated by enzyme-linked immunosorbent assay (ELISA), IL-4 and IL-13 signal protein STAT6 was measured by western blotting. Our study demonstrated that matrine inhibited OVA-induced increases in Raw and eosinophil count; IL-4 and IL-13 were recovered. Histological studies demonstrated that matrine substantially inhibited OVA-induced eosinophilia in lung tissue. Western blotting studies demonstrated that matrine substantially inhibited STAT6 protein level. These findings suggest that matrine may effectively ameliorate the progression of asthma and could be used as a therapy for patients with allergic asthma.     

Effects of globularifolin on cell survival,nuclear factor-κB activity,neopterin production,tryptophan breakdown and free radicals in vitro

The potential effects of globularifolin, an acylated iridoid glucoside, on cell survival, inflammation markers and free radicals scavenging were investigated. Viability assay on human myelomomonocytic cell line THP-1 and human peripheral blood mononuclear cells (PBMC) using the Cell-Titer Blue assay proved that globularifolin had no toxic effect at the tested concentrations. Conversely, it is proportional to the dose globularifolin increased growth of THP-1 cells (p < 0.01). On human PBMC, globularifolin at 6.25 and 12.5 μM concentrations showed a stimulatory effect, while at 12.5–200 μM it suppressed response of PBMC to stimulation with phytohemagglutinin (PHA). Globularifolin (50–200 μM) enhanced neopterin formation dose-dependently, whereas tryptophan breakdown was not influenced. At 50–200 μM in unstimulated PBMC in THP-1 cells, globularifolin induced a significant expression of nuclear factor-κB (NF-κB) as was quantified by Quanti-Blue assay. By contrast, in lipopolysaccharide (LPS)-stimulated cells, the higher concentrations of globularifolin suppressed NF-κB expression dose-dependently and a significant decrease was observed at 200 μM concentration. A positive correlation was found between increased neopterin and NF-κB activity (p < 0.01). Similarly, a positive correlation was observed between neopterin levels in mitogen-induced cells and NF-κB activity in LPS-stimulated cells after treatment with globularifolin (p = 0.001). The free radical scavenging capacity of globularifolin evaluated by Oxygen Radical Absorbance Capacity (ORAC) assay showed relative ORAC values of 0.36 ± 0.05 μmol Trolox equivalent/μmol. All together, results show that natural antioxidant globularifolin might represent a potential immunomodulatory as well as proliferative agent, which deserves further in vitro and in vivo studies.     

Lactones from Ligusticum chuanxiong Hort. reduces atherosclerotic lesions in apoE-deficient mice via inhibiting over expression of NF-kB -dependent adhesion molecules

The present study aims to investigate the anti-atherosclerotic effects of lactones extracted from Ligusticum chuanxiong Hort (LLC) in apoE-deficient mice (ApoE^−/− mice) and proclaim its underlying mechanisms. Expression of endothelial adhesion molecules and NF-κB around the atherosclerotic lesions was detected by immunohistochemistry (IHC). To further validate the mechanism, effect of LLC on the secretion of ICAM-1 and VCAM-1 of human umbilical vein endothelial cells (HUVECs) induced by tumor necrosis factor α (TNF-α) was measured by ELISA. And the activation of NF-κB was detected by western blot. Mice treated with LLC showed significant reduction in lesion sizes of thoracic segments of the aorta (p < 0.01). Meanwhile, LLC treatments lead to decreases of serum TG, TC and LDL-C contents, respectively. LLC also decreased the expression of CD31, intercellular adhesion molecule-1 (ICAM-1), monocyte chemoattractant protein-1 (MCP-1) and nuclear factor-kappa B (NF-κB) in the atherosclerotic plaque. Moreover, LLC at 3.125–25 μg/mL can dose-dependently attenuate the expression of ICAM-1 and VCAM-1 in TNF-α stimulated HUVECs. Western blot result indicated LLC inhibited activation of NF-κB. These results suggested that LLC could ameliorate atherosclerosis in ApoE^−/− mice. The mechanism of action of LLC on anti-atherosclerotic effect may be attributed to the suppression of the production of NF-κB-dependent adhesion molecules.     

Modulation of COX,LOX and NFκB activities by Xanthium spinosum L. root extract and ziniolide

Xanthium spinosum L. (Asteraceae) is a medicinal weed distributed worldwide. Many of its diverse ethnopharmacological uses – namely diarrhoea, inflammation, liver disorders, snake bite and fever – are linked – at least in part – to an uncontrolled release of arachidonic acid metabolites. The crude extract of X. spinosum roots from Jordanian origin dose-dependently inhibited the 5-LOX (IC₅₀ ≅ 10 μg/mL), COX-1(IC₅₀ ≅ 50 μg/mL), and 12-LOX (IC₅₀ ≅ 170 μg/mL) enzymatic pathways in intact pro-inflammatory cells. A direct activity at the level of PLA₂ is not probable, but the extract induced the synthesis of the anti-inflammatory eicosanoid 15(S)-HETE, which may in turn inhibit this enzyme. 5-LOX bioguided fractionation of the crude extract led to the isolation of ziniolide, a known 12,8-guaianolide sesquiterpene lactone, from the hydro-alcoholic fraction of the n-hexane extract (IC₅₀ = 69 μM). Both the plant extract and ziniolide are in vitro inhibitors of the phorbol-induced NFκB activation, a key regulator of the arachidonic pathway.     

Structural characterization and antioxidant activity of a low-molecular polysaccharide from Dendrobium huoshanense

The present study aimed at investigating the structural features and antioxidant activities of a polysaccharide fraction (DHP1A) obtained from Dendrobium huoshanense, a precious herb medicine in China. DHP1A mainly consisted of mannose (Man), glucose (Glc) and a trace of galactose (Gal), with a molecular weight of 6700 Da. Its backbone contained (1 → 4)-linked α-D-Glcp, (1 → 6)-linked α-D-Glcp and (1 → 4)-linked β-D-Manp, with a branch of terminal β-D-Galp. The in vitro antioxidant evaluation revealed that DHP1A had a remarkable inhibition effect on the FeCl₂-induced lipid peroxidation. Furthermore, DHP1A pretreatment decreased the production of malondialdehyde (MDA), and restored the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), as well as the level of glutathione (GSH) in the livers of CCl₄-treated mice. These results suggested that DHP1A was a potential antioxidant component in D. huoshanense.     

New cytotoxic triterpenoid saponins from the whole plant of Clematis lasiandra Maxim

Four new oleanane type triterpenoid saponins (1–4) and three known saponins (5–7) were isolated from the whole plant of Clematis lasiandra Maxim. The structures of the four new compounds were elucidated as 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 4)]-β-d-xylopyranosyl hederagenin (1), 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl oleanolic acid 28-O-β-d-glucopyranosyl ester (2), 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl hederagenin (3) and 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 4)]-α-l-arabinopyranosyl hederagenin (4) on the basis of extensive spectroscopic analysis and chemical evidence. Compounds 1–7 were evaluated for their cytotoxicity against human tumor cell lines HL-60, Hep-G2 and SGC-7901, and all of the evaluated saponins showed significant cytotoxicity to those three tumor cell lines with IC₅₀ in the range from 1.40 to 19.50 μmol/L except for compounds 2 and 6.     

The vascular protective properties of kinsenoside isolated from Anoectochilus roxburghii under high glucose condition

Anoectochilus roxburghii is a traditional Chinese herb used for the treatment of diabetes and some other diseases. The vascular protective effect of its major active ingredient, kinsenoside, in high glucose conditions was investigated in in vivo and in vitro experiments. In in vivo tests, kinsenoside (50 and 100 mg/kg) efficiently lowered blood glucose and cholesterol levels and it enhanced the oxidation resistance of diabetic mice induced by streptozotocin. In the in vitro assay, kinsenoside (20 and 50 μg/mL) markedly inhibited changes in various biochemical substances (nitric oxide (NO), lactic dehydrogenase (LDH), superoxide dismutase (SOD), and catalase (CAT)) in human umbilical vein endothelial cells (HUVECs) damaged by high glucose (35 mM) and restored vascular endothelial structure by balancing the matrix metalloproteinases–the tissue inhibitors of matrix metalloproteinases (MMP–TIMP) system. The vascular protective effects of kinsenoside were speculated to be attributed to oxidative stress inhibition and the reduction of nuclear factor kappa B (NF-κB) mRNA expression levels in high glucose conditions. Moreover, histological examination, including hematoxylin–eosin (H&E) staining, masson trichrome (Masson) staining, and periodic Schiff-methenamine (PASM) staining, greatly supported the morphological and functional amelioration of diabetes-related changes in mice aortas after kinsenoside (20 and 50 μg/mL) treatment. These results indicated that kinsenoside might be a promising agent for the treatment of diabetic vascular disease.     

Genotype × environment interactions in selected loblolly and slash pine plantations in the Southeastern United States

Few studies have quantified the combined effects of silvicultural treatments and genetic improvement on unit area production of full-sib family blocks of loblolly (Pinus taeda L.) and slash pine (P. elliottii Engelm. var. elliotttii). Efficient operational deployment of genetic materials requires an understanding of possible site and silvicultural treatment interactions to maximize yield potential. We examined genotype (family) by environmental interactions (G × E) through age 5 years using a factorial experiment consisting of silvicultural treatment intensity (operational versus intensive), planting density (1334 versus 2990 trees ha⁻¹) and families (seven elite full-sib loblolly and six elite full-sib slash pine families). In January of 2000, randomized complete block, split-plot experiments were installed at two locations for each species in southeast Georgia and northeast Florida. Five years after planting, both loblolly and slash pine demonstrated significant interactions among several factors: genotype × location (p < 0.028 and p < 0.016, respectively), genotype × silvicultural treatment intensity (p < 0.055 and p < 0.059), and silvicultural treatment intensity × density (p < 0.002 and p < 0.001) for basal area (BA) and standing stem volume (VOL). Genotype × silvicultural treatment interactions were positive, with the best overall performing families responding the greatest to intensive treatment. There were changes in slash pine family rankings between locations, which were partly explained by reductions in growth associated with a combination of fusiform rust infection [Cronartium quercum (Berk.) Miyabe ex Shirai f. sp. fusiforme] and wind damage from the 2004 hurricane season. No three-way interactions, which included family, were evident and all genetic sources were stable across the contrasting planting densities. At age 5, loblolly pine outperformed slash pine (p < 0.0001), especially under the intensive silvicultural intensity. While loblolly performance was similar whether deployed in mixtures or pure family blocks, slash pine tended to be more productive in intimate mixtures than when grown in pure family blocks (p = 0.0754 for aboveground biomass).     

Estimation of biomass and net primary productivity of major planted forests in China based on forest inventory data

Reforestation and afforestation have been suggested as an important land use management in mitigating the increase in atmospheric CO₂ concentration under Kyoto Protocol of UN Framework Convention on climate change. Forest inventory data (FID) are important resources for understanding the dynamics of forest biomass, net primary productivity (NPP) and carbon cycling at landscape and regional scales. In this study, more than 300 data sets of biomass, volume, NPP and stand age for five planted forest types in China (Larix, Pinus tabulaeformis, Pinus massoniana, Cunninghamia lanceolata, Pouulus) from literatures were synthesized to develop regression equations between biomass and volume, and between NPP and biomass, and stand age. Based on the fourth FID (1989–1993), biomass and NPP of five planted forest types in China were estimated. The results showed that total biomass and total NPP of the five types of forest plantations were 2.81 Pg (1 Pg = 10¹⁵ g) and 235.65 Mg ha⁻¹ yr⁻¹ (1 Mg = 10⁶ g), respectively. The area-weighted mean biomass density (biomass) and NPP of different forest types varied from 44.43 (P. massoniana) to 146.05 Mg ha⁻¹ (P. tabulaeformis) and from 4.41 (P. massoniana) to 7.33 Mg ha⁻¹ yr⁻¹ (Populus), respectively. The biomass and NPP of the five planted forest types were not distributed evenly across different regions in China. Larix forests have the greatest variations in biomass and NPP, ranging from 2.7 to 135.37 Mg ha⁻¹ and 0.9 to 10.3 Mg ha⁻¹ yr⁻¹, respectively. However, biomass and NPP of Populus forests in different region varied less and they were approximately 50 Mg ha⁻¹ and 7–8 Mg ha⁻¹ yr⁻¹, respectively. The distribution pattern of biomass and NPP of different forest types closely related with stand ages and regions. The study provided not only with an estimation biomass and NPP of major planted forests in China but also with a useful methodology for estimating forest carbon storage at regional and global levels.     

Pharmacokinetic and metabolism studies of rohitukine in rats by high performance liquid-chromatography with tandem mass spectrometry

A sensitive, selective, and rapid high performance liquid chromatography–tandem mass spectrometry (LC–MS/MS) was developed for the quantification of rohitukine in rat plasma. HPLC was performed using a Symmetry-Shield C₁₈ (5 μ, 4.6 × 150 mm) column, and isocratic elution with ammonium acetate buffer (pH 4; 10 mM):methanol (08:92, v/v) at a flow rate of 0.6 mL/min. Sample clean-up involved solid phase extraction (SPE) of analyte and internal standard (phenacetin) from 100 μL plasma. The parent → product ion transitions (MRM) for analyte and IS were 306.1 → 245.1 m/z and 180.1 → 138.1 m/z respectively, and were monitored on a triple quadrupole mass spectrometer, operating in positive ion mode. The method was validated across the dynamic concentration range of 5–500 ng/mL for rohitukine, with a fast run time of 4.5 min. The analytical method measured concentrations of rohitukine with accuracy (% bias) of <± 10% and precision (% RSD) of <± 12%. Rohitukine was stable during the battery of stability studies viz., bench-top, auto-sampler, freeze/thaw cycles and 30 days of storage in a freezer at − 70 ± 10 °C. Finally, the applicability of this assay has been successfully demonstrated in vivo pharmacokinetic and in vitro metabolism studies in Sprague–Dawley rat. This method will therefore be highly useful for future preclinical and clinical pharmacokinetic studies of rohitukine.     

Utilization and traditional strategies of in situ conservation of iroko (Milicia excelsa Welw. C.C. Berg) in Benin

Socio-cultural surveys were carried out on the basis of a questionnaire administered on 346 respondents in order to investigate cultural and ethnobotanic uses of Milicia excelsa in Benin.M. excelsa contributes to cure 45 human diseases. The different parts of the tree used are leaves (30.3%), bark (25.8%), root (23.6%), latex (10.1%), flaking bark (6.7%), wood, calcium concentrated in old trees, and gum (1.1% each). Fruits or seeds are rarely used. Six different forms of utilization were recorded: soaking (46.3%), bark or leaves decoction (32.8%), herb tea (11.9%), powder (6.0%), leaves or bark grounded and rolled up into ball (1.5%), component of offering to fetish (1.5%). Iroko wood is also used in carpentry and joinery for construction purposes; furniture as well as for building boats/canoes.Iroko tree is used as the conservatory of cultural values and incarnates many divinities, which differ significantly from one province to another (χ² = 1830.27; d.f. = 25; P < 0.01%). There is a significant difference between the provinces in respect of the recognition of the species (χ² = 268.71; d.f. = 17; P ≤ 0.01%) and the population awareness about iroko as a sacred tree also varied from one province to another (χ² = 308.66; d.f. = 27; P ≤ 0.01%).Veneration of the tree is the main approach of its conservation by local people. M. excelsa is conserved on farm, in sacred groves, in public places and in cemeteries. The different sacred objects used to symbolize the divinities incarnated by iroko are: pottery (36.36%), iron (11.11%), calabash (4.04%), candle (2.02%), piece of cloth (18.18%), sacrifice (13.13%), piece of money (3.0%), stone (2.05%), glassware (broken bottle, 2.02%), and convent (8.08%). There is a highly significant difference between provinces as far as the sacred objects are concerned (χ² = 183.037; d.f. = 19 and P < 0.001%). The conservation purposes also vary significantly from one region to other (χ² = 894.47; d.f. = 31; P < 0.01%).     

Two novel saponins of 20, 26-epoxy derivatives of pseudojujubogenin from the seeds of Hovenia trichocarpa

Two new saponins of 20, 26-epoxy derivatives of pseudojujubogenin, hoduloside XI (1) and hoduloside XII (2) were isolated from the seeds of Hovenia trichocarpa. The structures of the new compounds were established by extensive NMR experiments and chemical methods. Hoduloside XI was confirmed to be 3-O-{β-d-glucopyranosyl(1 → 3)-[β-d-xylopyranosyl(1 → 2)]-α-l-arabinopyranosyl}-20, 26-epoxypseudojujubogenin. Hoduloside XII was identified as 3-O-{β-d-xylopyranose(1 → 2)glucopyranosyl(1 → 3)[rhamnopyranose(1 → 2)]β-d-glucopyranosyl}-20, 26-epoxypseudojujubogenin. The in vitro cytotoxic activity of compounds 1 and 2 was assayed. They displayed inhibitive activities against human cancer cell lines HL60 and K562.     

Estrogenic and anti-estrogenic activities of hispolon from Phellinus lonicerinus (Bond.) Bond. et sing

Hispolon was the main antitumor active ingredient in Phellinus sensu lato species. In order to confirm the dual regulating estrogenic ingredient and obtain more effective natural estrogen replacement drugs, hispolon was separated from Phellinus lonicerinus (Bond.) Bond. et sing. Hispolon exhibited significant anti-proliferative effect against estrogen-sensitive ER (+) MCF-7 cells in the absence of estrogen, and exhibits antagonistic effects on 17β-estradiol (E₂)-induced MCF-7 cell proliferation when E₂ and the different concentrations of hispolon were treated simultaneously. Hispolon also inhibited the proliferation of estrogen-negative ER (−) MDA-MB-231 cells at the concentration of 5.00 × 10^− 5 M. The yeast two-hybrid experiments showed that hispolon had strong and non-selective effects on the estrogen receptor (ER) α and ERβ at a concentration of 1.00 × 10^− 6 M. The ERβ-binding ability of hispolon was larger than ERα in the concentration range of 1.00 × 10^− 9 M and 1.00 × 10^− 7 M. Hispolon could increase the body weight coefficient, serum E₂ and progesterone contents in immature female mice at dose of 9.10 × 10^− 6 mol/kg, and increase coefficient of thymus and spleen in mice. The Gscores of hispolon-ERα and hispolon-ERβ docked complexes were − 7.93 kcal/mol and − 7.79 kcal/mol in docking simulations. Hispolon presented dual regulating estrogenic activities, which showed estrogenic agonist activity at low concentration or lack of endogenous estrogen, and the estrogenic antagonistic effect was stimulated at high concentrations or too much endogenous estrogen. Hispolon could be used for treating the estrogen deficiency-related disease with the benefit of non-toxic to normal cells, good antitumor effects and estrogenic activity.     

Can intensive management accelerate the restoration of Brazil's Atlantic forests?

Only 7% of the once extensive forest along the eastern coast of Brazil remains, and much of that is degraded and threatened by agricultural expansion and urbanization. We wondered if methods similar to those developed to establish fast-growing Eucalyptus plantations might also work to enhance survival and growth of rainforest species on degraded pastures composed of highly competitive C₄ grasses. An 8-factor experiment was laid out to contrast the value of different intensities of cultivation, application of fertilizer and weed control on the growth and survival of a mixture of 20 rainforest species planted at two densities: 3 m × 1 m, and 3 m × 2 m. Intensive management increased seedling survival from 90% to 98%, stemwood production and leaf area index (LAI) by ～4-fold, and stemwood production per unit of light absorbed by 30%. Annual growth in stem biomass was closely related to LAI alone (r² = 0.93, p < 0.0001), and the regression improved further in combination with canopy nitrogen content (r² = 0.99, p < 0.0001). Intensive management resulted in a nearly closed forest canopy in less than 4 years, and offers a practical means to establish functional forests on abandoned agricultural land.     

Population structure and nut yield of a Bertholletia excelsa stand in Southwestern Amazonia

Although Brazil nut (B. excelsa) is often touted as one of the most economically successful NTFPs, little is known about the population structure of this species within its natural range in Southwestern Amazonia or ecological factors that affect fruit production. Since these are considered fundamental for sustainable resource management, we examined a natural Brazil nut stand in an extractive reserve in Acre, Brazil, posing the following questions: (1) What is the spatial distribution, species density, and size–class structure of B. excelsa? and (2) What tree-level factors influence Brazil nut production? In a 420 ha census, 568 trees ≥10 cm diameter at breast height (dbh) were counted, resulting in a density of 1.35 trees ha⁻¹. Based on the nearest-neighbor method, an index of aggregation (R) of 0.77 indicated a rejection of the null hypothesis of a strictly random distribution pattern. Yet, this value suggests a much greater tendency toward randomness than either clumping or uniformity. Our data do not show the commonly reported existence of groves, referring to clearly defined clusters of 50 to several hundred trees separated from similar clusters by great distances. Almost 1/4 of the population (23%) was composed of non-reproductive juveniles. Maximum R² improvement analysis applied to four distinct diameter classes provided insight into the dynamics of production-related variables over the species life cycle. While dbh explained 1/3 of production variance (R² = 0.3360) in the smallest diameter class (10 cm ≤ dbh < 50 cm), which included those in the process of reaching reproductive maturity, crown form best explained production variance of very large trees (dbh ≥ 100 cm). Results also demonstrated a significant negative correlation between crown vine load and production of trees ≥ 50 cm dbh (r = −0.13, P = 0.008), suggesting the need for further study on vine cutting as a possible silvicultural treatment for enhancing nut yields.     

The inhibitory effect of piperine from Fructus piperis extract on the degranulation of RBL-2H3 cells

Allergy is an abnormal immune response to an allergen. Type I hypersensitivity is an immunoglobulin (Ig) E-mediated allergic disorder. Fructus piperis is derived from the ripe fruit of the pepper, which is widely used as a spice in human diets and is also administered as a medicine in many countries. Piperine has been shown to have anti-oxidant, anti-depressant, anti-tumor, and anti-inflammatory activities. However, the effect of piperine on IgE-mediated allergic responses has not been reported. Here, the rat basophilic leukemia cells by membrane chromatography (RBL-2H3/CMC) coupled to high performance liquid chromatography/mass spectrometry (HPLC/MS) to discover and identify piperine can bind to RBL-2H3 cell membranes. Piperine inhibited the expression of cytokines, and the release of both β-hexosaminidase and histamine, which could be stimulated by antigen in RBL-2H3 mast cells. We found that the levels of intracellular Ca^2 + also decreased. Furthermore, RT-PCR showed that the mRNA expression levels of IL-4, IL-13, and TNF-α were significantly suppressed by piperine. The inhibitory effect of piperine on IgE-mediated degranulation and cytokine production by RBL-2H3 cells may be caused by the inhibition of IgE-mediated signaling pathways, including the phosphorylation of Lyn, p38, Erk, and Ras. In summary, piperine can inhibit antigen-induced allergic reactions that control degranulation.     

Chemical constituents of Swertia yunnanensis and their anti-hepatitis B virus activity

Four new triterpenoids, sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4), along with nineteen known compounds (5–23) were isolated from Swertia yunnanensis. Based on extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, UV, IR, [α]_D), the structures of sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4) were elucidated as taraxer-14-ene-3α,6β-diol, oleanolic acid 28-O-β-d-glucopyranosyl-(1 → 2)-O-β-d-glucopyranoside, 2α,3β-di-hydroxyolean-12-en-28-oic acid 28-O-β-d-glucopyranosyl(1 → 6)-β-d-glucopyranosyl (1 → 6)-β-d-glucopyranosyl(1 → 2)-β-d-glucopyranoside and hederagenin 28-O-β-d-glucopyranosyl(1 → 6)-β-d-glucopyranosyl(1 → 6)-β-d-glucopyranosyl(1 → 2)-β-d-glucopyranoside, respectively. Twenty-two compounds were evaluated for their anti-HBV activities on the HepG 2.2.15 cell line in vitro, of which nine compounds showed potent anti-HBV activities. Compounds 1, 5–6, 14–16 and 19 showed activities against the secretion of HBsAg (IC₅₀ values from 0.10 to 1.76 mM) and HBeAg (IC₅₀ values from 0.04 to 1.41 mM), and compounds 11 and 13–16 exhibited significant inhibition on HBV DNA replication (IC₅₀ values from 0.01 to 0.09 mM).     

Distribution,colonization and diversity of arbuscular mycorrhizal fungi associated with central Himalayan rhododendrons

The objective of the present study was to investigate arbuscular mycorrhizal status of five species of rhododendrons distributed in Kumaun region of the Indian Central Himalaya. Root and rhizosphere soil samples of all the five species of rhododendrons, namely, Rhododendron anthopogon, R. arboreum, R. campanulatum, R. barbatum and R. lepidotum were collected from temperate, sub-alpine to alpine location in altitudinal range from 1500 to 4500 m amsl. The arbuscular mycorrhizal colonization in root samples ranged from 28 to 42%; and maximum and minimum colonization was observed in R. arboreum and R. lepidotum, respectively. The highest number of intraradical vesicles (12.5 ± 2.8 cm⁻¹ root segment) was recorded in R. arboreum and the lowest (7.0 ± 1.7 cm⁻¹ root segment) in R. barbatum; vesicles were not observed in R. lepidotum. Spores were extracted from the rhizosphere soil by wet sieving to perform microscopic identification of the species. The maximum and minimum populations of spores were detected in the rhizosphere soil samples of R. anthopogon (52.0 ± 1.5 spores 25 g⁻¹ soil) and R. lepidotum (32.0 ± 2.5 spore 25 g⁻¹ soil), respectively. Spore populations were found to belong to five genera—Acaulospora, Glomus, Gigaspora, Sclerocystis and Scutellispora; genus Glomus was found to be dominant in the rhizosphere soil samples of all the rhododendron species. The most frequent and abundant species was G. fasciculatum, however, this species was not isolated from the rhizosphere soil of R. barbatum. Finger millet (Eleucine coracana) was used to cultivate the trap culture of arbuscular mycorrhizal fungi to confirm the species identity. Spores of Glomus pustulatum, not detected in the rhizosphere soil, were recovered from the trap culture. Contrary to this, genus Gigaspora, which was present in the rhizosphere soil, did not sporulate in the trap culture. Shannon and Wiener index of diversity and Simpson's index of dominance indicated that the species richness, dominance and diversity of arbuscular mycorrhizal fungi decrease with increasing altitude. In two species of rhododendrons, namely R. campanulatum and R. anthopogon, dark septate mycelium was also observed.