Cardiovascular effects of Hyptis fruticosa essential oil in rats

In non-anesthetized normotensive rats, Hyptis fruticosa essential oil (HFEO, 5, 10, 20 and 40 mg/kg; i.v.) induced hypotension associated with tachycardia. In intact and isolated rings of rat superior mesenteric artery (control), HFEO (1-1000 microg/ml, n=6, cumulatively) induced concentration-dependent relaxations of tonus induced by 10 microM phenylephrine (Phe) (pD(2)=2.6+/-0.27; E(max)=64+/-8.3%). In denuded endothelium pre-contracted rings with Phe or K(+)-depolarizing solution (80 mM), the concentration-response curves to HFEO were not shifted (pD(2)=2.3+/-0.25 and 2.3+/-0.28, respectively), but their maximal responses were significantly (P<0.05 vs control) increased (E(max)=122.3+/-18.2% and 92+/-3.6%, respectively). HFEO was also capable of antagonizing the concentration-response curves to CaCl(2) (3 microM-30 mM) in a dose-dependent manner.     

Antihypertensive effect of an aqueous extract of the calyx of Hibiscus sabdariffa

The present study was designed to investigate the efficacy of an aqueous calyx extract of Hibiscus sabdariffa (HS) in two forms of experimental hypertension: salt-induced and L-NAME (N(omega)-L-arginine methyl ester)-induced and in normotensive controls. The blood pressure and heart rate fell dose-dependently in both the hypertensive and normotensive rats after intravenous injection of 1-125 mg/kg of HS, suggesting that HS possesses anti-hypertensive, hypotensive and negative chronotropic effects. The fall in mean arterial pressure was significantly pronounced in the hypertensive rats (salt-induced: 94.4+/-8.6 mm Hg; L-NAME-induced: 136.5+/-10.3 mm Hg) than in the normotensive controls (50.2+/-5.1 mm Hg; P<0.05).     

Evaluation of aqueous and ethanolic extracts of saffron, Crocus sativus L., and its constituents, safranal and crocin in allodynia and hyperalgesia induced by chronic constriction injury model of neuropathic pain in rats

The current study was designed to evaluate therapeutic potential of systemically administered ethanolic and aqueous extracts of saffron as well as its bioactive ingredients, safranal and crocin, in chronic constriction injury (CCI)-induced neuropathic pain in rats. The von Frey filaments, acetone drop, and radiant heat test were performed to assess the degree of mechanical allodynia, thermal allodynia and thermal hyperalgesia respectively, at different time intervals, i.e., one day before surgery and 3, 5, 7 and 10 days post surgery. The ambulatory behavior was evaluated using the open field test. A 7-day treatment with the ethanolic and aqueous extracts (50,100 and 200 mg/kg, i.p.) and safranal (0.025, 0.05 and 0.1 mg/kg, i.p.), attenuated the behavioral symptoms of neuropathic pain in a dose dependent manner. Crocin even at the high dose (50 mg/kg) failed to produce any protective role. However, gabapentine (100 mg/kg) as a reference drug significantly alleviated all behavioral manifestations of neuropathic pain compared to control group. In conclusion, the results of this study suggest that ethanolic and aqueous extracts of saffron as well as safranal could be useful in treatment of different kinds of neuropathic pains and as an adjuvant to conventional medicines.     

Antihyperglycemic activity of the aqueous extract of Urtica dioica

When administered 30 min before glucose loading, the aqueous extract of Urtica dioica (nettle) (250 mg/kg) showed a strong glucose lowering effect. The decrease of glycemia has reached to 33+/-3.4% of the control value 1 h after glucose loading. This effect was persistent during 3 h. In contrast, nettle did not show hypoglycemic effect in alloxan-induced diabetic rats. The amount of glucose absorbed in a segment jejunum in situ was 8.05+/-0.68 mg in presence of nettle extract vs. 11.11+/-0.75 mg in control rats during 2 h (P<0.05). The results indicate that nettle has a significant antihyperglycemic effect in OGTT model. This effect may be caused in part by the reduction of intestinal glucose absorption. LD(50) is 3.5 g/kg (i.p.).     

Passiflora alata and Passiflora edulis spray-dried aqueous extracts inhibit inflammation in mouse model of pleurisy

The aqueous leaves extracts of Passiflora alata (100-300 mg/kg, i.p.) and Passiflora edulis (100-1000 mg/kg, i.p.) possess a significant antiinflammatory activity on carrageenan-induced pleurisy in mice. Treatment with the extracts inhibited leukocyte migration and reduced the formation of exudate. Moreover, a significant inhibition of myeloperoxidase and adenosine-deaminase activities was observed at the doses tested (100 or 250 mg/kg, i.p.). At the same doses, a significant decrease of serum C-reactive protein was observed.     

Stimulation of gastric acid secretion and intestinal motility by Vernonia amygdalina extract

Aqueous extract of Vernonia amygdalina infused intragastrically at a dose of 10 mg/ml to rats induced a significant increase in acid output which was reduced by, ranitidine (5 mg/kg b.w.) or atropine (1.2 microMol/kg b.w.). Moreover the extract evoked a dose-dependent contraction of the guinea pig ileum at a dose range of 0.6 mg/ml to 66 mg/ml which was inhibited by atropine (2.4 x 10(-8)-2.4 x 10(-6) M).     

Evaluation of analgesic, anti-inflammatory and hepatoprotective effects of lycorine from Sternbergia fisheriana (Herbert) Rupr

The present study reports the potential antinociceptive, anti-inflammatory and hepatoprotective activities of lycorine from Sternbergia fischeriana (Herbert) Rupr. (Amaryllidaceae). Lycorine was evaluated on mice by using acetic-acid induced writhing and tail-flick tests. Lycorine exhibited stronger inhibition than aspirin in acetic-acid induced abdominal stretching at 1.0 mg/kg dose. Lycorine also showed antinociceptive activity at 1.0 mg/kg dose in tail-flick test. The anti-inflammatory activity of lycorine was not found to be significant at dose of 0.5 mg/kg. However, at doses of 1.0 mg/kg and 1.5 mg/kg, i.p. showed a significant reduction with 53.45% and 36.42%, respectively in rat paw oedema induced by carrageenan against the reference anti-inflammatory drug indomethacin (3 mg/kg, i.p.) (95.70%). The ED₅₀ of lycorine was determined as 0.514 mg/kg. Hepatoprotective activity of lycorine on carbon tetrachloride (CCl₄) induced acute liver toxicity following biochemical parameters were also evaluated. Rats were treated with lycorine at doses of 1.0 mg/kg and 2.0 mg/kg, i.p. Results of biochemical tests were confirmed by histopathological examination. Lycorine exhibited significant hepatoprotective effect at dose of 2.0 mg/kg i.p. dose.     

Pro-cognitive activity induced in the rat by low doses of R-(+)-hyoscyamine

In the passive-avoidance test R-(+)-hyoscyamine (10-100 microg kg(-1) i.p.) prevented amnesia induced by antimuscarinic treatment with AF-64A and benzhexol. The antiamnesic effect of R-(+)-hyoscyamine was comparable to that exerted by the cholinesterase inhibitor physostigmine (0.2 mg kg(-1) i.p) and the M(1) selective agonist AF-102B (10 mg kg(-1) i.p.). In the social learning test, R-(+)-hyoscyamine (10-100 microg kg(-1) i.p.) in adults rats, reduced the duration of active exploration of the familiar partner in the second session of the test similar to the nootropic drug piracetam (30 mg kg(-1) i.p.). These results demonstrated the ability of R-(+)-hyoscyamine to modulate memory functions and suggest that R-(+)-hyoscyamine could be useful in the treatment of cognitive deficits.     

Antiinflammatory activity of Sambucus ebulus hexane extracts

Hexane extracts of aerial parts (flowered browes), leaves and roots of Sambucus ebulus were investigated for their antiinflammatory activity in rats. Aerial parts and roots extracts produced statistically significant and dose dependent inhibition of edema induced by carrageenan at all doses when compared to the control groups. On the contrary, hexane extract of leaves did not show any activity up to 600 mg/kg i.p. The highest activity was showed in the aerial parts and roots that at 600 mg/kg i.p. inhibited inflammation by ca. 80% (78% for diclofenac at 100 mg /kg i.p.). No extracts exhibit toxicity when injected up to 2 g/ kg intraperitoneally in mice.     

Antidiabetic potential of Butea monosperma in rats

The antihyperglycemic activity of the ethanolic extract of Butea monosperma (BMEE) was studied in glucose-loaded and alloxan-induced diabetic rats. Single dose treatment of BMEE (200 mg/kg, p.o.) significantly improved glucose tolerance and caused reduction in blood glucose level in alloxan-induced diabetic rats. Repeated oral treatment with BMEE (200 mg/kg/day) for 2 weeks significantly reduced blood glucose, serum cholesterol and improved HDL-cholesterol and albumin as compared to diabetic control group.     

Hepatoprotective activity of the Indian medicinal plant Polygala arvensis on D-galactosamine-induced hepatic injury in rats

The suspensions of chloroform extract of leaves in 0.3% carboxy methyl cellulose (CMC) was evaluated for hepatoprotective activity in Wistar albino rats by inducing hepatic injury with d-galactosamine (400 mg/kg). The chloroform extract of Polygala arvensis at an oral dose of 200 mg/kg and 400 mg/kg exhibited a significant (P<0.001, P<0.01 and P<0.05) protection effect by normalizing the levels of aspartate amino transferase (ASAT, GOT), alanine amino transferase (ALAT, GPT), alkaline phosphatase (ALP), total bilirubin (TB), lactate dehydrogenase (LDH), total cholesterol (TC), triglycerides (TGL), albumin, total protein (TP) which were significantly (P<0.001) increased in rats by treatment with 400 mg/kg i.p. of d-galactosamine. Silymarin (25 mg/kg), a known hepatoprotective drug used for comparison exhibited significant activity (P<0.001).     

Anti-diabetic activity of flowers of Hibiscus rosasinensis

The ethanol extract of flowers of Hibiscus rosasinensis at doses of 250 mg/kg and 500 mg/kg significantly reduced the blood glucose level in both acute (1, 3, 5 h) and sub acute (1, 3, 5, 7 days) treatments.     

Antinociceptive diterpene from Euphorbia decipiens

One myrsinol-type diterpene ester (1) isolated from Euphorbia decipiens was evaluated for analgesic activity in the acetic acid induced writhing test in mice. Different dose (5-20 mg/kg i.p.) of the compound showed significant antinociceptive activity, which was comparable to standard analgesic drugs, aspirin and ibuprofen (100 mg/kg i.p.).     

A growth model of a single sugi (Cryptomeria japonica) tree based on the dry matter budget of its aboveground parts

Growth of a single sugi (Cryptomeria japonica (L.f.) D. Don.) tree was analyzed on the basis of a dry matter budget. The aboveground net production rate and death rate were defined as the anabolic rate and catabolic rate, respectively. Growth rate of aboveground tree weight, v(w) (kg(dw) year(-1)), was defined as follows: v(w) = v(p) - v(d) (1) where v(p) (kg(dw) year(-1)) is the aboveground net production rate and v(d) (kg(dw) year(-1)) is the aboveground death rate. The value of v(d) is obtained by measuring the monthly clippings of new dead leaves and branches attached to a sample tree. The value of v(w) was calculated as the annual difference in the estimated aboveground tree weight, w(T) (kg(dw)). Finally, the value of v(p) was estimated as the sum of the values of v(d) and v(w). The following allometric relationships were found between v(p) and w(T) and between v(d) and w(T): v(p) = aw(T) (alpha), v(d) = bw(T) (beta) (2). Combining Equations 1 and 2 gives a growth equation, Bertalanffy's equation, of the sample tree. dw(T)/dt = v(w) = aw(T) (alpha) - bw(T) (beta) (3). Because the growth curve of w(T) was derived from Equation 3, the analysis of the growth of w(T) is based on direct measurement of the dry matter budget.     

Hypoglicemic effect of Leandra lacunosa in normal and alloxan-induced diabetic rats

Leandra lacunosa, popularly known as "erva-do-jabuti", is used in Brazilian folkloric medicine for the treatment of diabetes mellitus. Based on this traditional indication, the aim of this work was to evaluate the hypoglycemic activity of the hydroalcoholic extract of L. lacunosa aerial parts (LLH) in normal and alloxan-induced diabetic rats. Chromatographic fractionation of LLH was also carried out by several techniques, affording isolation of the following major compounds: ursolic acid (1), kaempferol (2), luteolin (3), and quercetin (4). The oral administration of LLH (500 mg/kg) in normal rats caused a significant reduction of 24.7% (P<0.05) in the blood glucose levels after 2 h of treatment, while the administration of chlorpropamide (20 mg/kg, p.o.) led to a reduction of 40.2% (P<0.01). After oral administration of glucose (10 g/kg, p.o.), LLH (500 mg/kg, p.o.) significantly inhibited the increase in blood glucose levels compared with the negative control group. The oral treatment with LLH (500 mg/kg) in alloxan-induced diabetic rats significantly reduced the blood glucose levels in 47.8% after 4 h of treatment, while chlorpropamide resulted in a significant reduction of 71.7% in the 4th hour. Our results showed that LLH, displays hypoglycemic activity, which may be related to the effect of the major compounds identified in the crude extract. This study seems to provide biological evidence for the folkloric use of L. lacunosa in the treatment of diabetes mellitus.     

Anticancer activities of two sesquiterpene lactones, millerenolide and thieleanin isolated from Viguiera sylvatica and Decachaeta thieleana

The present study was carried out in order to examine the anticancer properties of two sesquiterpene lactones, millerenolide and thieleanin, isolated from Viguiera sylvatica and Decachaeta thieleana, against cell lines in vitro, and on the growth B16/BL6 melanoma tumors in C57BL/6 mice. Millerenolide and thieleanin showed a similar pattern of cytotoxicity with the greatest effect on viability being evident with A549 human lung cancer cells (IC(50) - 40 and 32 microM respectively), and with the 3T3/HER2 cell line which are 3T3 mouse fibroblasts transfected with the HER2 oncogene (IC(50) - 16 and 28 microM respectively). The parent 3T3 cells and the B16/BL6 mouse melanoma cells were less sensitive to these compounds, with thieleanin showing an IC(50) with B16/BL6 greater than the highest dose tested (203 microM). Treatment with millerenolide (8 mg/kg, i.p. on days 0, 2 and 4 post-inoculation) significantly inhibited the growth of subcutaneous B16/BL6 tumors in C57BL/6 mice, (50% inhibition at day 25, P=0.015), as well as retarding the appearance of detectable tumor (millerenolide - day 15.2+/-0.4 vs control - day 12.8+/-0.5, mean+/-SEM, P=0.011). In contrast, treatment with thieleanin (8 mg/kg every other day up to the day of kill) neither retarded the appearance of the tumor nor its growth.     

Maintenance and growth respiration of the aboveground parts of young field-grown hinoki cypress (Chamaecyparis obtusa)

Aboveground respiration of five 8-year-old trees of field-grown hinoki cypress (Chamaecyparis obtusa (Sieb. et Zucc.) Endl.) was nondestructively measured at monthly intervals over 1 year with an enclosed standing tree method. The relationship between monthly specific respiration rate and monthly mean relative growth rate at the individual tree level was described by a linear equation. During the dormant season, respiration was used mainly for maintenance purposes, whereas during the growing season, more than 40% of the respiration was used for growth purposes, i.e., 60 to 70% in May. We conclude that annual maintenance and growth respiration of a tree are directly proportional to the aboveground phytomass and its annual increment, respectively. The maintenance coefficient was estimated to be 0.504 +/- 0.039 (SE) kg kg(-1) year(-1), indicating that the amount respired for maintaining already existing phytomass was equivalent to about half of the existing phytomass. The growth coefficient was estimated to be 0.772 +/- 0.043 (SE) kg kg(-1), indicating that the amount respired for constructing new phytomass was equivalent to about three-fourths of the annual phytomass increment. The annual stand maintenance and growth respiration were, respectively, 8.8 Mg ha(-1) year(-1) for an aboveground biomass of 17.4 Mg ha(-1) and 5.0 Mg ha(-1) year(-1) for an annual stand aboveground biomass increment of 6.5 Mg ha(-1) year(-1). About two-thirds of the total respiration was used to maintain already existing biomass, and about one-third was used to construct new biomass.     

我国油橄榄中试园土壤条件及其营养指标的研究

1983—1987年对湖北省武昌、宜昌、当阳县和陕西省城固县油橄榄中试园土壤与营养状况进行了研究。结果表明:油橄榄生长较好的(一类树下)土壤条件是pH7—8,CaCO_3>5％,有机质>1.8％,速效N>74.4—87.4mg/kg土,速效P>40mg/kg土,速效K>200mg/kg土,交换性Ca103—181mmol/kg土,交换性Mg24—34mmol/kg土。生长结实好的一类树叶片营养指标为N2.0—2.5％,P_2O_5 0.14％,K_2O 1.5％,CaO 4.0％,MgO 0.8％。通过分析建立了预测产量和施肥控制的回归方程。     

Studies on preventive and curative effects of berberine on chemical-induced hepatotoxicity in rodents.

Berberis aristata is an edible plant employed in the South Asian Traditional Medicine, particularly its fruits being used as a tonic remedy for liver and heart. In this investigation, berberine, a known compound from this plant, was studied for its possible antihepatotoxic action in rats. Pretreatment of animals with berberine (4 mg/kg; orally twice daily for 2 days) prevented the acetaminophen- or CCl4-induced rise in serum levels of alkaline phosphatase (ALP) and aminotransaminases (AST and ALT), suggestive of hepatoprotection. Post-treatment with three successive oral doses of berberine (4 mg/kg every 6 h) reduced the hepatic damage induced by acetaminophen, while CCl4-induced hepatotoxicity was not modified, suggesting a selective curative effect against acetaminophen. Pretreatment of animals with a single oral dose of berberine (4 mg/kg) induced prolongation of the pentobarbital (60 mg/kg, i.p.)-induced sleeping time as well as increased strychnine (0.3 mg/kg; i.p.)-induced toxicity, suggestive of inhibitory effect on microsomal drug metabolizing enzymes, cytochrome P450s (CYPs).     

Antiinflammatory activity of Polygala japonica extract

The antiinflammatory activity of the aqueous extract of Polygala japonica (AEPJ) was investigated in mice and rats to find the pharmacological basis for its ethnomedical use. The extract produced a significant inhibition of peritoneal and cutaneous vascular permeability induced by acetic acid and histamine, respectively and ear swelling induced by picryl chloride in mice at the dose of 25.0 mg/kg. Moreover, the extract markedly inhibited footpad edema induced by histamine in rats, and decreased prostaglandin E(2) (PGE(2)) content in carrageenan-induced air-pouch at doses of 12.5 and 6.25 mg/kg respectively.