Inhibition of mitochondrial respiratory chain is involved in triptolide-induced liver injury

Triptolide, a diterpenoid epoxide, is one of the major active ingredients of Tripterygium wilfordii Hook F, a woody vine plant called lei gong teng in China, which is used in traditional Chinese Medicine (TCM) for treating many diseases. In this paper, we investigate the relation between inhibition of mitochondrial respiratory chain and liver injury induced by triptolide. Results indicate that the secondary β-oxidation impairment caused by inhibition of mitochondrial respiratory chain is involved in triptolide-induced liver injury, which featured by microvesicular steatosis, hyperlactacidemia and enhanced oxidant stress, although other mechanisms of triptolide-induced liver injury may also exist.     

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.     

Hepatoprotective effect of curcumin in lipopolysaccharide/-galactosamine model of liver injury in rats: relationship to HO-1/CO antioxidant system

This work studied a relationship between HO-1/CO system and lipid peroxidation with consequent effects on liver functions and NOS-2. We focused on curcumin pretreatment in rat toxic model of d-galactosamine and lipopolysaccharide. Hepatocyte viability, lipid peroxidation, antioxidant status, ALT and AST were evaluated. HO-1 and NOS-2 expressions and respective enzyme activity were determined. Curcumin caused decreases in ALT and AST levels as well as in lipid peroxidation. Furthermore, curcumin pretreatment increased liver HO-1 (2.4-fold, p = 0.001), but reduced NOS-2 (4.1-fold, p = 0.01) expressions. In conclusion, the tuning of CO/NO pathways is important in shedding light on curcumin's cytoprotective effects in this model.     

Hepatoprotection of Phyllanthus maderaspatensis against experimentally induced liver injury in rats

The hexane extract of Phyllanthus maderaspatensis (200 and 100 mg/kg) showed significant hepatoprotection on carbon tetrachloride and thioacetamide induced liver damage in rats. The protective effect was evident from serum biochemical parameters and histopathological analysis. Rats treated with P. maderaspatensis remarkably prevented the elevation of serum AST, ALT and LDH and liver lipid peroxides in CCl(4) and thioacetamide treated rats. Hepatic glutathione levels significantly increased by the treatment with the extracts. Histopathological changes induced by CCl(4) and thioacetamide were also significantly reduced by the extract treatment. The activity of hexane extracts of P. maderaspatensis was comparable to that of silymarin, the reference hepatoprotective drug.     

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.     

Hepatoprotective effect of Ginkgoselect Phytosome in rifampicin induced liver injury in rats: evidence of antioxidant activity

The protective effects of Ginkgoselect Phytosome((R)) (GBP) on Rifampicin (RMP) induced hepatotoxicity and the probable mechanism(s) involved in this protection were investigated in rats. Liver damage was induced in Wistar rats by administering rifampicin (500 mg/kg, p.o.) daily for 30 days. Simultaneously, GBP at 25 mg/kg and 50 mg/kg, and the reference drug silymarin (100 mg/kg) were administered orally for 30 days/daily to RMP treated rats. Levels of marker enzymes (SGOT, SGPT and SALP), albaumin (Alb) and total proteins (TP) were assessed in serum. The effects of GBP on lipid peroxidation (LPO), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GR) were assayed in liver homogenates to evaluate antioxidant activity. GBP (25 and 50 mg/kg) and silymarin elicited a significant hepatoprotective activity by lowering the levels of serum marker enzymes and lipid peroxidation and elevated the levels of GSH, SOD, CAT, GPX, GR, Alb and TP in a dose dependant manner. The present findings suggest that the hepatoprotective effect of GBP in RMP induced oxidative damage may be related to its antioxidant and free radical scavenging activity.     

Whole-plant adjustments in coconut (Cocos nucifera) in response to sink-source imbalance

Coconut (Cocos nucifera L.) is a perennial tropical monocotyledon that produces fruit continuously. The physiological function of the large amounts of sucrose stored in coconut stems is unknown. To test the hypothesis that reserve storage and mobilization enable the crop to adjust to variable sink-source relationships at the scale of the whole plant, we investigated the dynamics of dry matter production, yield and yield components, and concentrations of nonstructural carbohydrate reserves in a coconut plantation on Vanuatu Island in the South Pacific. Two treatments were implemented continuously over 29 months (April 2002 to August 2004): 50% leaf pruning (to reduce the source) and 100% fruit and inflorescence pruning (to reduce the sink). The pruning treatments had little effect on carbohydrate reserves because they affected only petioles, not the main reserve pool in the stem. Both pruning treatments greatly reduced dry matter production of the reproductive compartment, but vegetative growth and development were negligibly affected by treatment and season. Leaf pruning increased radiation-use efficiency (RUE) initially, and fruit pruning greatly reduced RUE throughout the experiment. Changes in RUE were negatively correlated with leaflet soluble sugar concentration, indicating feedback inhibition of photosynthesis. We conclude that vegetative development and growth of coconut show little phenotypic plasticity, assimilate demand for growth being largely independent of a fluctuating assimilate supply. The resulting sink-source imbalances were partly compensated for by transitory reserves and, more importantly, by variable RUE in the short term, and by adjustment of fruit load in the long term. Possible physiological mechanisms are discussed, as well as modeling concepts that may be applied to coconut and similar tree crops.     

N-Methyl-6, 7-dimethoxyisoquinolone in Annona squamosa twigs is the major immune modifier to elicit polarized Th1 immune response in BALB/c mice

Annona squamosa (AS) has traditionally been used as ethnomedicine. We have earlier extracted and fractionated the twigs of AS based upon its bioactivity and observed its immune potentiating activity that was localized in its three fractions. Present communication deals with the phytochemical analysis and pharmacological investigation of the most active chloroform fraction that led to isolation and identification of a number of compounds whose structures were elucidated using 1D and 2D NMR spectroscopic analysis. Amongst the twelve pure compounds isolated, five compounds Lanuginosine (1), (+) -O- methylarmepavine (2), (+)-anomuricine (3), Isocorydine (4), and N-methyl-6, 7-dimethoxyisoquinolone (5) were evaluated in vivo for their immune modifier activities in BALB/c mice after oral administration at three log doses of 0.3, 1.0 and 3.0 mg/kg for 14 consecutive days. Of these, three compounds (1, 2 and 5) showed dose dependent immune stimulating activity. However, the uppermost activity was noted in the compound N-methyl-6, 7-dimethoxyisoquinolone at the 3.0 mg/kg oral dose. The activity was assessed in the form of increased splenic T and B cellular proliferation, up-regulated CD4+, CD8+ and CD19+ cell population and accentuation in the peritoneal macrophage function. The compound possibly acted modifying the expression of Th1- and Th2- cytokines via stimulation of pro-inflammatory Th1 cytokines IL-2 and IFN-γ. These results warrant the use of the above compounds as an efficient immune-stimulant or immune-adjuvant against diseases with immune suppression. The analogs of the compound may further be chemically synthesized to achieve desired immune modifying activity.     

Population status and gender imbalance of the marula tree, Sclerocarya birrea subsp. caffra in northern Namibia

The population status of many wild fruit trees that support rural people in Africa remains poorly understood despite its importance for their management. Here, we establish a baseline for size class distribution and gender ratios for marula (Sclerocarya birrea subsp. caffra), a widespread but sparsely distributed species of wooded farmland, that has both traditional importance to rural communities and an emerging commercial potential. A population of marula trees around two neighbouring villages in northern Namibia was surveyed in August 2001. The stem diameter at 1.3 m height (dbh) of all individuals ge1 cm dbh in 40 fields, totalling 286 ha in area, was measured and their gender was recorded as female, male or unknown. Over 400 trees were enumerated, the largest >100 cm dbh. Despite the low threshold (1 cm dbh) for inclusion, relatively few trees (around 40%) were ¡20 cm dbh, suggesting the population may not be self-sustaining. The area was nevertheless well-stocked, with ca 1 tree ha^?1 ge20 cm dbh – an unusually high density for Sclerocarya. Tree gender becomes evident when individuals reach about 15 cm dbh. In one village, the sex ratio of larger trees (40–80 cm dbh) was significantly skewed in favour of females. This was attributed to selective elimination of individuals that have failed to fruit and was much less pronounced in the second village. The sparse distribution and gender imbalance of trees have implications in relation to management requirements for ensuring adequate pollen flow.     

Coast live oak, Quercus agrifolia, susceptibility and response to goldspotted oak borer, Agrilus auroguttatus, injury in southern California

Oak mortality is often associated with a complex of decline factors. We describe the morphological and physiological responses of coast live oak, Quercus agrifolia Née, in California to an invasive insect, the goldspotted oak borer (GSOB), Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), and evaluate drought as a potential inciting factor. Morphological traits of 356 trees were assessed and physiological traits of 70 of these were monitored intensively over one growing season. Morphological characteristics of tree health included crown thinning and dieback; bole staining resulting from larval feeding; density of GSOB adult exit holes; and holes caused by woodpecker feeding. These characteristics were used to rank GSOB infestation/injury into four classes, and taken together, they explained 87% of the variation in a principal component analysis. Drought stress on various size/age and infestation classes of Q. agrifolia was measured by assessing branchlet pre-dawn and solar noon xylem water potential, leaf cell turgor potential, and water use efficiency over one growing season. Both morphological and physiological traits were highly variable in mature and old growth trees. Early summer plant water status (branchlet xylem water potential and water use efficiency) was similar between uninfested and newly colonized trees, suggesting that GSOB are not pre-selecting drought-stressed Q. agrifolia for oviposition. By late summer, leaf water and cell turgor potentials were lower in infested than in uninfested mature trees, suggesting that GSOB infestation causes drought stress in these trees. Among the tree size/age classes, infested old growth trees exhibited the greatest change in water use efficiency over the growing season, and showed greater morphological injury symptoms of decline than infested mature trees. Morphological attributes of decline in Q. agrifolia associated with GSOB were correlated weakly with increasing physiological drought stress among infestation classes of trees. We propose that the collection of morphological responses of Q. agrifolia to GSOB described here can be used to monitor the future expansion of the GSOB distribution as well as the GSOB-induced decline of Q. agrifolia in California.     

17个核桃品种(系)抗病性接种试验

为给品种(系)适应性研究提供理论依据,采用温室栽培17个核桃品种(系),人工接种核桃黑斑病、核桃褐斑病等病原物,调查统计叶片感病指数,比较不同核桃品种(系)抗病能力大小。结果表明,品种间抗病性间差异显著。17个品种(无性系)叶片抗病性从低到高依次是鲁果1号、鲁果3号、重庆、泰勒、岱香、云新7926、云新7914号、元丰、京746、香玲、中林5号、鲁光、辽宁1号、清香、自选45号、云新8064号、泡核桃。多重比较结果表明:鲁果1号与中林5号、鲁光、辽宁1号、清香、自选45号、云新8064号、泡核桃的抗病性间存在显著差异;鲁果3号与云新8064号、泡核桃的抗病性间存在显著差异;泡核桃分别与鲁果1号、鲁果3号、重庆、泰勒、岱香、云新7926号、云新7914号、元丰的抗病性间存在显著差异。     

庞泉沟保护区鸟类近十七年变化情况的研究

笔者于１９９６年对庞泉沟自然保护区内鸟类的数量和分布进行了调查，与１７年前相比，鸟类的数量和分布都发生了明显的变化，垂直分布有向上迁移的趋势。分析认为：生态环境的人为破坏和人类活动的影响是造成鸟类生态分布变化的主要原因     

第十七届广州园博会艺术园圃植物造景特点浅析

第十七届广州园林博览会,是亚运会后广州市举办的首次大型园林展览,以“梦想·花园·家”为主题。作为园博会的重要展览项目之一的艺术园圃,打破了以往临时展园统揽全园的传统做法,分为永久性园圃和临时性园圃,目的是为游客提供更加丰富多彩的园林艺术展品。本文以艺术园圃的植物景观营造为切入点,对本届艺术园圃的植物景观特点及艺术特色进...     

Freezing cycles enhance winter injury in Picea rubens

We examined changes in chlorophyll absorbency in red spruce (Picea rubens Sarg.) foliage in response to simulated freezing cycles. Current-year branch tips were collected from 16 trees on January 8, January 20, February 8 and February 26, 1996. Tissue was subjected to freezing cycle treatments with a minimum of -35 degrees C and a maximum of 3 degrees C for a one-cycle treatment, and -9, -6, -3, 0 or 3 degrees C for four-cycle treatments. Samples were frozen at a rate of 5 degrees C h(-1), and warmed at 12 to 15 degrees C h(-1). Controls were held at -9 degrees C. Temperatures during the three-day periods preceding each sample date averaged -18, 4.7, -9.6 and 3.7 degrees C, respectively. On January 8, treated trees showed no significant (P > 0.1) increase in the breakdown of chlorophyll, as measured by the ratio of chlorophyll a absorbency (435 nm) to phaeophytin a absorbency (415 nm), compared with control branch tips. On later sampling dates, seven trees consistently exhibited needle reddening and nine exhibited few symptoms (< 10% of total needle surface reddened) after four-cycle treatments. On February 26, chlorophyll degradation in trees with needle reddening differed (P < 0.05) from the control by 26, 26, 16, 14 and 15% for the 3, 0, -3, -6 and -9 degrees C maxima, respectively. No detectable chlorophyll degradation occurred after a one-cycle treatment in any trees on any sampling date. Freezing cycles with sub-zero maxima and a -35 degrees C minimum enhanced winter injury in red spruce after a midwinter thaw had rendered the trees susceptible to freezing damage.     

Production of decay-resistant sapwood in response to injury

Summary Mechanical injury to the sapwood of Quercus alba, Robinia pseudoacacia, and Maclura pomifera resulted in the formation of discolored tissue which was more resistant to decay fungi than the adjacent uninjured sapwood but usually less resistant than the heartwood. Considerable tree-to-tree variation in response to injury, as measured by subsequent variations in decay resistance, was noted. The exact cause for this induced decay resistance is unknown, but it appears to be due to fungistatic substances produced in situ by the dying parenchymous cells in the xylem.This work was supported by Grants GB-5313 and GB-7550 from National Science Foundation. Michigan Agricultural Experiment Station Journal Article No. 4925.     

广州市17种引入植物的耐热性评价与分析

为了解17种(含种下分类单位)引入植物在广州地区的越夏能力,通过植物的田间生长状态、叶绿素含量、叶面温度等指标进行耐热性分析.实验结果表明,聚类分析(Ward最小方差)将17种引入植物分为耐热类群和不耐热类群,耐热类群在高温环境下性状较为稳定,包括柳枝稷Panicum virgatum、萱草Hemerocallis f...     

17个阔叶树种在退化马尾松林的早期生长表现

对东莞莲花山自然保护区退化马尾松林林分2002年种植的17个3年生阔叶树种的树高、胸径以及冠幅进行测量和分析。结果表明,各个树种之间树高、胸径和冠幅生长均存在极显著差异(P<0.01)。除红荷、桃花心木、仪花、格木和马占相思以外,其余12个树种树高与胸径生长表现出显著正相关(P<0.05)。综合树高、胸径和冠幅3个指标对17个阔叶树种的生长数据进行聚类分析,桃花心木、火力楠、铁冬青、尖叶杜英和仪花生长较慢;枫香、格木、红锥、米老排、樟树、木荷、木棉和南洋楹生长速度中等;红荷和黧蒴生长较快;千年桐和马占相思生长迅速。总体而言,试验的17个阔叶树种对退化马尾松林的景观恢复取得一定成效。     

黑木相思17号无性系在桂东地区早期生长表现

为丰富桂东地区速生树种多样性以及为生态敏感地区桉树改造提供新的树种,2017年5月在桂东地区试种黑木相思17号无性系20hm^2,分别在造林后第8个月和14个月调查试验林不同海拔、坡向、坡位的林分生长情况,试验结果表明:黑木相思17号无性系在桂东地区造林成活率85%以上,造林后第8个月成活率、地径和树高分别为92%,3.1cm和2.3m,造林第14个月地径、胸径和树高分别为7.4cm,5.8cm和5.0m;黑木相思造林后8-14个月,上坡生长表现优于下坡,海拔200m生长表现优于海拔320m。说明黑木相思17号无性系适合在桂东地区生长,避开谷底和山脚等光照不足地块、及时抚育是黑木相思在桂东地区造林成功的关键。     

Biochemical studies on the hepatoprotective effect of Picrorrhiza kurroa on changes in liver mitochondrial respiration and oxidative phosphorylation in -galactosamine-induced hepatitis in rats

Oral pre-treatment with alcoholic extract of Picrorrhiza kurroa rhizomes and roots (50 mg/kg/day for 10 days) significantly prevented the -galactosamine-induced alterations in respiration and oxidative phosphorylation of liver mitochondria.     

(RS)-glucoraphanin purified from Tuscan black kale and bioactivated with myrosinase enzyme protects against cerebral ischemia/reperfusion injury in rats

Ischemic stroke is the result of a transient or permanent reduction in cerebral blood flow caused by the occlusion of a cerebral artery via an embolus or local thrombosis. Restoration of blood supply to ischemic tissues can cause additional damage known as reperfusion injury that can be more damaging than the initial ischemia.This study was aimed to examine the possible neuroprotective role of (R_S)-glucoraphanin, bioactivated with myrosinase enzyme (bioactive R_S-GRA), in an experimental rat model of brain ischemia/reperfusion injury (I/R). R_S-GRA is a thiosaccharidic compound found in Brassicaceae, notably in Tuscan black kale (Brassica oleracea L. var. acephala sabellica).The mechanism underlying the inhibitory effects of bioactive R_S-GRA on inflammatory and apoptotic responses, induced by carotid artery occlusion in rats, was carefully examined. Cerebral I/R was induced by the clamping of carotid artery for 1 h, followed by 40 min of reperfusion through the release of clamp.Our results have clearly shown that administration of bioactive R_S-GRA (10 mg/kg, i.p.) 15 min after ischemia, significantly reduces proinflammatory parameters, such as inducible nitric oxide synthase expression (iNOS), intercellular adhesion molecule 1 (ICAM-1), nuclear factor (NF)-kB traslocation as well as the triggering of the apoptotic pathway (TUNEL and Caspase 3 expression).Taken together our data have shown that bioactive R_S-GRA possesses beneficial neuroprotective effects in counteracting the brain damage associated to I/R. Therefore, bioactive R_S-GRA, could be a useful treatment in the cerebral ischemic stroke.