Effect of Cydonia oblonga Mill. fruit and leaf extracts on blood pressure and blood rheology in renal hypertensive rats

Ethnopharmacological relevance

Quince, Cydonia oblonga Mill. (COM), is used in traditional Uyghur medicine to treat or prevent cardiovascular diseases. Uyghur people have greater longevity and lower blood pressure than other central Asian populations. We therefore tested COM fruit and leaf extracts on blood pressure and rheology in renal hypertensive rats (RHR).

Materials and methods

Two-kidney, one-clip (2K1C) renal hypertensive rats were divided randomly into eleven groups: sham, model, and model treated with daily doses of 80 and 160 mg/kg aqueous or ethanol extracts of COM fruit or leaves, or 25 mg/kg captopril (n=10 per group), given orally once daily for 8 weeks. Blood pressure was measured before treatment and every 2 weeks thereafter. Blood rheology was tested after 8 weeks.

Results

Model rats had higher blood pressure than sham 8 weeks after the procedure (systolic blood pressure 193±7 vs. 138±8 mmHg, p<0.05). Those treated with captopril had decreased blood pressure within 2 weeks but that did not return to the level found in the sham group at 8 weeks (167±7, p<0.05 vs. model). With the COM extracts, the effect on blood pressure was notable after 4 weeks. At 8 weeks blood pressure was similar with captopril and with 160 mg ethanol leaf extract (166±4, p<0.05 vs. model), the most effective of the extracts. Model rats had higher blood viscosity and lower erythrocyte deformability than sham. Captopril had little effect on blood rheology; whereas COM extracts reduced whole blood viscosity and improved erythrocyte deformability to levels approaching those found in sham.

Conclusions

COM extracts have antihypertensive activity in renal hypertensive rats. The additional effect on rheology, compared to captopril, may convey added interest. Further studies of these effects in man appear warranted.     

Combined antihypertensive effect of luteolin and buddleoside enriched extracts in spontaneously hypertensive rats

Ethnopharmacological relevance

Flos Chrysanthemi is used in a variety of diseases in traditional Chinese medicine including hypertension, and the total flavonoids (rich in luteolin (LUT) and buddleoside (BUD)) of Flos Chrysanthemi is known to modulate vascular functions and reduce the blood pressure. However, the active flavonoids and their synergistic effects on anti-hypertension are still unclear. To investigate the combined anti-hypertension effects of LUT and BUD enriched extracts on spontaneously hypertensive rats (SHR), as well as the anti-hypertensive mechanism of LUT&BUD mixture.

Materials and methods

CODA Mouse & Rat Tail-Cuff Blood Pressure System was used to measure the systolic blood pressure (SBP) and diastolic blood pressure (DBP) of SHR after treated with extracts contains with LUT and/or BUD. The expressions of Ang II, PRA, ALD, ET, PGI₂ and TXB₂ were investigated by ELASA. Serum NO concentration was measured by the method of Nitric acid reductase.

Results

A single administration of LUT, BUD, or LUT:BUD=1:1 significantly reduced SBP by about 3.35 mmHg, 4.39 mmHg and 15.42 mmHg, respectively. Chronic administration of LBM (at 60 mg/kg; p.o. for 30 days) reduced both SBP and DBP by 4.04% and 5.24% of the vehicle group, respectively. Oral administration of LBM at 60 mg/kg inhibited the serum levels of ANG, ALD and ET, but increased serum NO concentration.

Conclusion

This study shows the synergistic anti-hypertension effects of LUT and BUD in SHR. The effects of LBM on blood pressure are associated with RAAS and endothelial system. Thus, our experiments suggest that the combination of luteolin and buddleoside from Flos Chrysanthemi are potentially useful for the therapeutic treatments for hypertension.     

Effect of the flavonoid fraction of Lithocarpus polystachyus Rehd. on spontaneously hypertensive and normotensive rats

Ethnopharmacological relevance

Lilhocarpus polystachys Rehd. (Sweet Tea, ST) is a folk herbal medicine that has been traditionally used as a natural remedy for hypertension in China, whose mechanism remains unveiled. Flavonoid fraction is considered as the major active components in ST. This study aimed to provide experimental evidence for the anti-hypertension activity of flavonoid fraction of ST (ST-F) and investigate the underlying mechanism. The effect of ST-F on the blood pressure of normotensive rats was also to be determined.

Materials and methods

Spontaneously hypertensive rats (SHRs) were treated with ST-F daily for 10 weeks. Blood pressure of SHRs was measured before and biweekly during ST-F treatment. Subsequently, animals were sacrificed either immediately at the end of treatment or 2 weeks after ST-F treatment discontinuance. The activities of plasma rennin (PRA), angiotensin II (Ang-I), endothelin (ET), nitric oxide (NO), superoxide dismutase (SOD) and malondialdehyde (MDA) were measured as well as skin microcirculatory flux. In normotensive rats, blood pressure was determined after six months' treatment of ST-F.

Results

ST-F treatment significantly reduced the blood pressure of SHRs along with decreasing plasma levels of PRA and Ang II. ST-F did not show obvious effects on plasma levels of ET, NO or SOD, but it significantly decreased the plasma level of MDA and improved skin microcirculatory flux. Compared to the anti-hypertensive drug enalapril, ST-F showed a modest effect on lowering blood pressure of SHRs without obvious withdrawal reactions. But long-term intake of ST-F did not change the blood pressure in normotensive rats.

Conclusion

ST-F had an antihypertensive effect on SHRs. The underlying mechanism could be related to modulation on the rennin–angiotensin–aldosterone system (RAAS) and antioxidation system, as well as regulation of skin microcirculation. Compared to its anti-hypertensive effect on SHRs, ST-F did not cause hypotension in normotensive rats. The results indicated that ST-F could potentially be used as natural drugs or functional foods for preventing hypertension.     

Effect of Cydonia oblonga Mill. leaf extract on serum lipids and liver function in a rat model of hyperlipidaemia

Ethnopharmacological relevance

Cydonia oblonga Mill. leaves are traditionally used in Uyghur medicine to treat or prevent cardiovascular disease. Beyond a demonstrated effect on thrombosis, we tested it for an effect on dyslipidemia, in a rat model of hyperlipidemia.

Methods

Seventy healthy Sprague Dawley rats were randomly divided into 6 groups: normal controls, model controls, simvastatin, and low-, medium- and high-dose Cydonia oblonga Mill. leaf extracts (COM), orally for 56 days. The normal controls were fed a normal diet, all other groups a high fat diet. Rat weights were recorded over time. Total cholesterol (TC), triglycerides (TG), low and high-density lipoproteins (LDL, HDL), as well as AST, ALT and total protein (TP) were measured in serum at the end of the study. The antioxidant capacity of glutathione peroxidase (GSH-PX), superoxide dismutase (SOD), malondialdehyde (MDA) was measured in liver samples, along with lipoprotein lipase (LPL), and hepatic lipase (HL). Liver pathology was described.

Results

COM dose-dependently reduced TC, TG, LDL-C and MDA, inhibited the activity of ALT, AST and LPS, increased HDL-C content, increased the activity of SOD, GSH-PX, LPL and HL, and reduced liver steatosis in hyperlipidaemia rats, which was significant at medium and high doses. The effect of COM was similar to that of simvastatin except for increased LPL and HL which were reduced by COM but not by simvastatin.

Conclusion

Cydonia oblonga Mill. leaf extracts have hypolipidaemic and hepatoprotective effects, probably related to increasing antioxidant capacity and lipoprotein metabolism in the liver, and inhibition of lipogenesis.     

Effects of leaf extracts from Croton zambesicus Müell. Arg. on hemostasis

Ethnopharmacological relevance

The leaf decoction of Croton zambesicus Müell. Arg. (Euphorbiaceae; syn. Croton amabilis Müell. Arg., Croton gratissimus Burch) is traditionally used in Benin to treat hypertension.

Aim of the study

As hypertension and thromboembolism are often associated in several cardiovascular diseases, we studied the potential effects of leaf extracts from Croton zambesicus on hemostasis.

Materials and methods

We prepared the dichloromethane and aqueous extracts from the air-dried leaves of Croton zambesicus and separated the aqueous extract in its aqueous and dichloromethane fractions. The potential effects of these four extracts/fractions were investigated on red blood cells integrity using spectrophotometric lysis assays, on primary hemostasis using platelet aggregation studies and on secondary hemostasis using calibrated automated thrombin generation assays and coagulation factors inhibition tests.

Results

In the in vitro testing, we found that none of the tested extracts/fractions exhibit hemolytic or antiplatelet activity. However, they display a moderate but significant anticoagulant activity which would be mediated through the direct inhibition of thrombin, FXa and TF/FVIIa. The active anticoagulant compound(s) seem to be mainly in the aqueous extract and especially in its aqueous fraction.

Conclusions

This experimental work reported for the first time the anticoagulant effect of leaf extracts from Croton zambesicus. These findings are of particular interest as the leaves from Croton zambesicus are commonly used in infusion by local population and may provide a new natural source for the development of original anticoagulant agents. Furthermore, this activity, associated with the vasorelaxant properties of some of its diterpenes may prove to be interesting for the prevention of cardiovascular diseases in traditional medicine.     

Echinacea increases arginase activity and has anti-inflammatory properties in RAW 264.7 macrophage cells,indicative of alternative macrophage activation

Ethnopharmacological relevance

The genus Echinacea is a popular herbal immunomodulator. Recent reports indicate that Echinacea products inhibit nitric oxide (NO) production in activated macrophages.

Aim of the study

In the present study we determined the inhibitory effects of alcohol extracts and individual fractions of alcohol extracts of Echinacea on NO production, and explored the mechanism underlying the pharmacological anti-inflammatory activity.

Materials and methods

Alcohol extracts of three medicinal Echinacea species, Echinacea angustifolia, Echinacea pallida and Echinacea purpurea, were prepared using Soxhlet apparatus and fractionated using HPLC. NO production by LPS activated RAW 264.7 macrophage cells was measured using a Griess reagent and iNOS detected using immunoblotting. In addition, effects on arginase activity were measured in RAW 264.7 cells stimulated with 8-bromo-cAMP +/− LPS.

Results

Alcohol extracts of all three Echinacea species significantly inhibited NO production by lipopolysaccharide (LPS)-activated the RAW 264.7 macrophage cell line; among them Echinacea pallida was the most active. The Echinacea-mediated decrease in NO production was unlikely due to a direct scavenging of NO because the extracts did not directly inhibit NO released from an NO donor, sodium nitroprusside. An immunoblotting assay demonstrated that the extract of Echinacea pallida inhibited inducible nitric oxide synthase (iNOS) protein expression in LPS-treated macrophages. The enzymes iNOS and arginase metabolize a common substrate, l-arginine, but produce distinct biological effects. While iNOS is involved in inflammatory response and host defense, arginase participates actively in anti-inflammatory activation. Arginase activity of RAW 264.7 cells stimulated with 8-bromo-cAMP was significantly increased by alcohol extracts of all three Echinacea species. The polar fraction containing caffeic acid derivatives enhanced arginase activity, while the lipophilic fraction containing alkamides exhibited a potential of inhibiting NO production and iNOS expression.

Conclusions

These results suggest that the anti-inflammatory activity of Echinacea might be due to multiple active metabolites, which work together to switch macrophage activation from classical activation towards alternative activation.     

Antihypertensive effect of Eucommia ulmoides Oliv. extracts in spontaneously hypertensive rats

Aim of the study

To investigate the antihypertensive fractions of Eucommia ulmoides Oliv. and their underlying mechanisms in spontaneously hypertensive rats (SHRs).

Materials and methods

In vivo study, Eucommia ulmoides lignans (EuL) and Eucommia ulmoides iridoids (EuI) were administrated to Sprague–Dawley (SD) rats and SHRs, and their blood pressures were measured. Plasma level of nitric oxide (NO) was measured by colorimetric method, and renin activity (RA) and plasma concentration of angiotensin II (Ang II) were measured by radioimmunoassay. In vitro study, rat mesenteric artery was treated with EuL and the vessel relaxation responses were determined.

Results

EuL could lower blood pressures of both SD rats and SHR dose-dependently by either intravenous (i.v.) or intragastric (i.g.) administration, but EuI failed to affect blood pressure in the two kinds of rats. Meanwhile, no synergistic effect was observed with the combination of EuL and EuI. The plasma level of NO in SHR treated with EuL 300 mg/kg twice a day was markedly increased. Both plasma RA and Ang II level were decreased with long-term oral treatment of EuL 150 and 300 mg/kg twice a day. In perfusion experiment, EuL relaxed mesenteric artery quickly and dose-dependently and the effect on the artery with and without endothelium was the same.

Conclusions

EuL may be the effective fraction to lowering blood pressure and its antihypertensive effect is probably associated with regulating NO and renin–angiotensin system (RAS) and directly relaxing artery.     

Antihypertensive effects of extract from Picrasma quassiodes (D. Don) Benn. in spontaneously hypertensive rats

Ethnopharmacologica relevance

Picrasma quassiodes (D. Don) Benn. (PQB) is a widely used herbal medicine used for gastroenteritis, snakebite, infection and hypertension in China. The aim of the study was to investigate the possible antihypertensive mechanisms on spontaneously hypertensive rats (SHR) of the extract from Picrasma quassiodes (D. Don) Benn.

Materials and methods

In the in vivo study, extract from Picrasma quassiodes (D. Don) Benn. at the dose of 50, 100, 200 mg/kg and captopril (12.5 mg/kg) were administrated to different group of SHR rats by gavage for six consecutive weeks after the blood pressures were firstly measured. At the end of the study, rats serum nitric oxide (NO) was measured by the nitrate reductase method; superoxide dismutase (SOD) and malondialdehyde (MDA) activities were measured by the colorimetric method; the expression of aorta endothelial nitric oxide synthase (eNOS) was measured by immunohistochemical analysis.

Results

The results showed that the oral administration of PQB could lower the systolic blood pressure (SBP) of SHR rats. In addition, the serum level of NO in SHR treated with PQB (100 and 200 mg/kg) was increased dramatically (P<0.05, P<0.01), but administration with captopril had no significant effect. The expression of aorta eNOS was markedly increased when treated with PQB. The serum SOD levels were increased with treatment of PQB (100 and 200 mg/kg; P<0.05, P<0.01). All the effects of these parameters were comparable to that of the SHR control group.

Conclusions

Our results disclosed that PQB is effective to lower blood pressure of SHR, its antihypertensive effect is probably associated with lowering oxidative stress by reducing SOD activity, preserving endothelial function and increasing the expression of eNOS to regulate NO and directly relax artery.     

In vivo anti-inflammatory activities of Ocimum suave in mice

Ethnopharmacological relevance

Ocimum suave has been used in the Ethiopian traditional medicine to relieve pain, fever, inflammation and other disease conditions.

Aim of the study

The aim of the present study was to investigate the anti-inflammatory activities of the aqueous and ethanol leaf extracts and some fractions of Ocimum suave in mice.

Materials and methods

The crude extracts were screened for their anti-inflammatory activities on carrageenan-induced mouse paw edema at three dose levels. The butanol and aqueous fractions of the aqueous extract were also evaluated for their anti-inflammatory activities using carrageenan, histamine and serotonin-induced mouse paw edema at three dose levels. Normal saline and aspirin were employed as negative and positive control groups, respectively.

Results

Both ethanol and aqueous extracts significantly decreased carrageenan-induced inflammation at all the three doses used. However, greater paw edema inhibition was observed with the aqueous extract. The two fractions also showed significant reduction of inflammation against inflammatory models in which the aqueous residue exhibited the highest inhibition.

Conclusions

From the present findings, it can be concluded that the ethanol and aqueous leaf extracts as well as butanol and aqueous fractions of Ocimum suave have shown anti-inflammatory properties.     

Effects of Cydonia oblonga Miller extracts on blood hemostasis,coagulation and fibrinolysis in mice,and experimental thrombosis in rats

Introduction

Cydonia oblonga Miller (COM) is traditionally used in Uyghur medicine for the prevention of cardiovascular disease. The present study is designed to explore the effects of COM extracts on models and markers of thrombosis and related biomarkers.

Materials and methods

20, 40, 80 mg/kg/day COM aqueous extracts and 5 mg/kg/day aspirin, orally for 14 days were compared to untreated controls in mice on bleeding and clotting times, using the tail cutting and glass slide methods and for death rates in collagen–epinephrine pulmonary thrombosis, thrombolysis in vitro and euglobulin lysis time (ELT). In rats, common carotid artery FeCl₃-induced thrombus and inferior vena cava thrombosis occlusion time, plasma concentrations of thromboxane B₂ (TXB₂) and 6-keto-prostaglandine F₁α (6-keto-PGF1α) were measured.

Results and conclusion

Compared to controls, COM extracts dose-dependently prolonged bleeding by 2.17, 2.78 and 3.63 times, vs. aspirin 2.58, and the clotting time by 1.44, 2.47 and 2.48 times, vs. aspirin 1.91. COM reduced pulmonary embolus mortality by 27, 40 and 53%, vs. 47% for aspirin. COM dose-dependently increased thrombolysis by 45, 55 and 63%, vs. 56% for aspirin, and shortened ELT to 71, 61 and 43%, vs. 43% for aspirin. In rats, venous occlusion time was prolonged. Arterial and venous thrombus weights were dose-dependently reduced in COM groups. TXB₂ decreased and 6-keto-PGF1α increased with COM and aspirin, with an association between 6-keto-PGF1α/TXB2 and arterial or venous thrombus weight for all products, and for occlusion time with COM but not for aspirin.

Conclusion

We confirm the experimental effects of COM on hemostasis and thrombosis. Further exploration of putative clinical effects appear justified.     

The cytotoxicity to leukemia cells and antiviral effects of Isatis indigotica extracts on pseudorabies virus

Aim of the study

Isatis indigotica (I. indigotica), Cruciferae, has been used in Chinese medicine for anti-leukemia and anti-severe acute respiratory syndrome (SARS). The aim of this study was to evaluate the cytotoxicity of Isatis indigotica extracts on human leukemia cell line (HL-60) and the antiviral activity on swine pseudorabies virus (PrV) in in vitro assays.

Materials and methods

Extracts and derived fractions of Isatisindigotica were prepared from root (R) and leaf (L) using methanol (M), ethyl acetate (E) and distilled water (D). The cytotoxic effect of extracts on swine peripheral blood mononuclear cells (PBMCs) and HL-60 was assessed by MTT method. The cytopathic effect (CPE) reduction, plaque reduction and inhibition assays on viral replication, and virucidal activity were further conducted to investigate the anti-PrV activity.

Results

Indirubin, one of the biological active compounds of Isatis indigotica, had the most significant cytotoxicity on HL-60 cells and inhibitory effect on PrV replication. Extracts from roots and leaves of Isatis indigotica also presented CPE inhibition either before or after infection of PrV on porcine kidney (PK-15) cells. Leaf extracts had better virucidal activity than roots, and ethyl acetate extracts exhibited the highest efficacy among extracts tested.

Conclusion

Isatis indigotica posses a valuable virucidal effect in disease control of pseudorabies virus infection in swine.     

Davilla elliptica and Davilla nitida: Gastroprotective,anti-inflammatory immunomodulatory and anti-Helicobacter pylori action

Ethnopharmacological relevance

Davilla elliptica and Davilla nitida are species commonly found in the Brazilian Cerrado biome.

Aim of the study

Based on ethnopharmacological and phytochemical analyses, methanolic extracts from leaves of Davilla elliptica (EDE) and Davilla nitida (EDN) were evaluated for their anti-ulcer, anti-inflammatory, immunological and anti-Helicobacter pylori activities.

Materials and methods

The gastroprotective action of both extracts was evaluated in rodent experimental models (HCl/ethanol, ethanol or NSAID). We also evaluated anti-inflammatory (carrageenin-induced rat hind paw edema), immunomodulatory (murine peritoneal macrophages) and antibacterial action of both extracts against a standard strain of Helicobacter pylori.

Results

EDE and EDN (500 mg/kg) were able to protect gastric mucosa against HCl/ethanol solution (EDE 63%; EDN 59%), absolute ethanol (EDE 95%; EDN 88%), and also against injurious effect of NSAID (EDE 77%; EDN 67%). When EDE and EDN were challenged with sulfhydryl depleter compound, the gastroprotective action of both extracts was completely abolished. EDE had gastroprotective effect related to increase of glutathione bioavailability and stimulated higher levels of NO, H₂O₂ and TNF-α production. Otherwise EDN showed better anti-Helicobacter pylori action than EDE. Neither extracts presented anti-inflammatory activity by oral route.

Conclusion

The phytochemical investigation showed that both extracts possess phenolic acid derivatives, acylglycoflavonoids and condensed tannins with evident quantitative variations that probably influenced the pharmacological differences between extracts.     

Antioxidant and anti-inflammatory activities of the phenolic extracts of Sapium sebiferum (L.) Roxb. leaves

Ethnopharmacological relevance

The leaves of Sapium sebiferum have long been used in Traditional Chinese Medicine (TCM) for the treatment of eczema, shingles, edema, swelling, ascites, scabs, and snakebites, among other maladies.

Aim of this study

The present study aimed to investigate the antioxidant and anti-inflammatory effects of the phenolic extracts of Sapium sebiferum leaves using in vitro and in vivo models.

Materials and methods

The in vitro antioxidant activities of the extracts were measured using common chemical methods (total phenolic content; total flavonoid content; scavenging of DPPH·, ABTS+·, superoxide, and nitrite radicals; reducing power; β-carotene bleaching; and FTC assays). The in vivo topical anti-inflammatory activities were tested using the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced dermatitis animal model. The SOD and CAT activities and the GSH content of ear tissue were also determined using test kits.

Results

The extracts of Sapium sebiferum leaves exhibited strong in vitro antioxidant activities. They also showed significant (P<0.001) and dose-dependent anti-inflammatory activities in an acute dermatitis model at the doses of 0.03 mg/ear, 0.1 mg/ear, and 0.3 mg/ear. The application of Sapium sebiferum leaf extracts increased the SOD and CAT activities and the GSH content relative to those of the TPA treatment group. The anti-inflammatory effect of the Sapium sebiferum leaf extract was positively correlated with its antioxidant activity.

Conclusion

These results demonstrate that Sapium sebiferum leaf extract is an effective anti-inflammatory agent in the TPA-induced dermatitis model, and its anti-inflammatory effect is related, at least in part, to its antioxidant activity.     

Antihypertensive effect of total flavone extracts from Puerariae Radix

Aim of the study

To evaluate the antihypertensive effect of total flavone extracts from Puerariae Radix (FEPR). To explore the hemodynamic profiles and pertinent mechanism of the extracts.

Materials and methods

Acute and chronic antihypertensive effects of FEPR were examined in spontaneous hypertensive rats (SHRs) and reno-hypertensive rats (two kidneys one clip model, 2K1C). Anesthetized dogs were used to evaluate the hemodynamic effects of FEPR. The determination of angiotensin converting enzyme (ACE) activity in vitro and plasma renin activity (PRA) and endothelin (ET) in vivo were used to study the pilot mechanism of FEPR. Moreover, the toxicity study of FEPR was evaluated.

Results

FEPR (100, 200 and 400 mg/kg, i.v.) notably reduced the blood pressure of SHRs in a short time period. A two-week administration of FEPR (45, 90 and 180 mg/kg, p.o.) decreased the blood pressure of both 2K1C rats and SHRs. The results of hemodynamic study in anesthetized dogs showed that, left ventricular end systolic pressure and left ventricular dP/dt_max had shown no significant difference between FEPR-treated dogs and those from the control group, while the cerebral blood flow increased significantly in FEPR-treated groups. FEPR significantly inhibited the ACE activities in vitro dose dependently, and inhibited the PRA in vivo, while the content of ET showed no difference in the FEPR treated group comparing with the control group.

Conclusions

FEPR shows significantly blood pressure lowering and cerebral vascular resistance (CVR) decreasing effect, which can partly be explained by the involvement of the Renin-Angiotensin-System (RAS).     

Anti-inflammatory effects of methanol extracts of the root of Lilium lancifolium on LPS-stimulated Raw264.7 cells

Aim of the study

Lilium lancifolium is commonly used to treat bronchitis, pneumonia, etc. In this study, we investigated the anti-inflammatory effects of methanol extracts of the root of Lilium lancifolium (LL extracts) in LPS-stimulated Raw264.7 cells.

Material and methods

Levels of NO, PGE₂ and pro-inflammatory cytokines (IL-6 and TNF-α) in the supernatant fraction were determined using sandwich ELISA. Expression of COX-2 and iNOS, phosphorylation of MAPK subgroups (ERK and JNK), and NF-κB activation in extracts were detected via Western blot and immunocytochemistry assays.

Results

The LL extract significantly inhibited NO, PGE₂, IL-6 and TNF-α production in LPS-stimulated cells, and suppressed iNOS and COX-2 expression. A mechanism-based study showed that phosphorylation of ERK1/2 and JNK and translocation of the NF-κB p65 subunit into nuclei were inhibited by the LL extract. Furthermore, interleukin-4 and interleukin-13 production in Con A-induced splenocytes was suppressed.

Conclusion

These results indicate that anti-inflammatory effects of methanol extracts from Lilium lancifolium are due to downregulation of iNOS and COX-2 via suppression of NF-κB activation and nuclear translocation as well as blocking of ERK and JNK signaling in LPS-stimulated Raw264.7 cells.     

A bioactivity guided study on the antidiabetic activity of Juniperus oxycedrus subsp. oxycedrus L. leaves

Ethnopharmacological relevance

Juniperus (Cupressaceae) species are widely used as folk medicine in spreading countries. Decoction of Juniperus oxycedrus subsp. oxycedrus L. leaves is used internally to lower blood glucose levels in Turkey.

Aim of the study

To determine hypoglycaemic and antidiabetic activities of Juniperus oxycedrus subsp. oxycedrus leaves and to identify active compounds through bioactivity guided isolation technique.

Materials and methods

Ethanol and water extracts of Juniperus oxycedrus subsp. oxycedrus (Joso), leaves on oral administration were studied using in vivo models in normal, glucose-hyperglycemic and streptozotocin-induced diabetic rats. Through in vivo bioactivity-guided fractionation processes, a nonpolar fraction was separated from the n-hexane subextract by silica gel column chromatography as the main active fraction. Subfractions of this fraction was found to possess antidiabetic activity and their chemical composition was investigated by GC-FID and GC–MS, simultaneously.

Results

This is the first report on the antidiabetic constituents of Joso leaves. Fatty acids, such as palmitic, linoleic and linolenic acid were found as the major compounds in subfractions.

Conclusion

Results indicated that Joso leaf extract and its active constituents might be beneficial for diabetes mellitus.     

Analgesic and anti-inflammatory effects of Cassia siamea Lam. stem bark extracts

Aim of the study

The present study was carried out to investigate analgesic and anti-inflammatory activities of Cassia siamea Lam stem bark extracts. We have also determined the cytotoxicity of each extract.

Materials and methods

C. siamea, a widespread medicinal plant traditionally used in sub-Saharan Africa, was collected in Congo Brazzaville. Stem bark was extracted with petroleum ether (CSE1), chloroform (CSE2), ethanol (CSE3) and water (CSE4). Analgesic, anti-inflammatory and antipyretic activities of these extracts were assessed in rats with hot plate test, paw pressure and carrageenan induced paw oedema. Cytotoxicity was assessed against KB and Vero cells.

Results

At the doses used (100, 200, and 400 mg/kg) ethanol and water extracts showed significant and dose-dependent analgesic and anti-inflammatory effects. None of the extracts had cytotoxic activity on KB and Vero cell lines and the most active extracts (CSE3 and CSE4) had no acute toxicity.

Conclusions

The study highlighted the analgesic and anti-inflammatory of C. siamea stem bark. Four major families of compounds present in the plant may explain these activities: triterpenes (lupeol, oleanolic acid, ursolic acid, friedelin, betulin), flavonoids (apigenin, kaempferol, luteolin), anthraquinones (emodin), phytosterols (stigmasterol, beta-sitosterol).     

Assessment of the genotoxic and mutagenic properties of Himatanthus articulatus bark extracts used as phytotherapeutic drug in the Amazon

Ethnopharmacological relevance

Himatanthus articulatus (Apocynaceae) is a plant native to the Amazon, popularly used to treat external ulcers, tumors, inflammations, cancer, syphilis and malaria.

Aim of the study

To investigate the in vivo genotoxic and mutagenic potential of this plant, using the comet assay and the micronucleus test.

Material and methods

Female and male adult mice were treated with 500 mg/kg, 1000 mg/kg or 2000 mg/kg of Himatanthus articulatus aqueous or ethanolic bark extracts by gavage for two consecutive days. In addition, blood slides were exposed to hydrogen peroxide (ex vivo) to evaluate the anticlastogenic effect using the comet assay. The HPLC analyses indicated plumieride as the main constituent of both extracts from Himatanthus articulatus barks.

Results

No differences between genders were observed. Micronuclei were observed only in the group treated with the highest dose of both extracts. Conversely, lower doses of these extracts showed protective effects to DNA against damage induced by hydrogen peroxide, indicating an important antigenotoxic effect.

Conclusions

The toxicological evaluation indicated that the extracts are non-genotoxic and reduce the clastogenic damage induced by hydrogen peroxide. In part, this result can be atributted to the phytochemical profile of Himatanthus articulatus, which presents iridoids and phenolic compounds.     

Anti-ulcer polysaccharides from Cola cordifolia bark and leaves

Ethnopharmacological relevance

Aqueous extracts of bark and leaves of C. cordifolia are traditionally used in Mali (West Africa) in the treatment of wounds and gastric ailments like abdominal pain, gastritis and gastric ulcers.

Aim of the study

To evaluate and compare the anti-ulcer and immunological activities, as well as the toxicity of polysaccharide rich water extracts from the bark and leaves of C. cordifolia.

Materials and methods

Gastric ulcers were induced in rats and the inhibition of ulcer formation was calculated based on lesion index. Immunological activities were measured by complement fixation and macrophage activation. Toxicity was tested on brine shrimps. The two extracts were characterised by GC, Yariv-precipitation and quantification of phenolic compounds. An ethnomedical survey on C. cordifolia was carried out in Siby (Mali, West-Africa) to generate more knowledge about the traditional use.

Results

Bark and leaf extracts from C. cordifolia significantly inhibited the formation of gastric lesions in rodents in a dose depending manner. CCbark50 showed a high complement fixation activity in vitro. No toxicity was found. The ethnomedical survey showed that C. cordifolia was mainly used for treating pain and wounds.

Conclusions

Our results shows that the bark and the leaves comprise a dose dependant anti-ulcer activity in an experimental rat model (no statistical difference between the plant parts). Clinical studies should be performed to evaluate the effect of both bark and leaves of C. cordifolia as a remedy against gastric ulcer in human.     

In vitro evidence of phyto-synergy for plant part combinations of Croton gratissimus (Euphorbiaceae) used in African traditional healing

Aim of the study

Despite the extensive traditional use of Croton gratissimus Burch. var. gratissimus for medicinal purposes, scientific studies validating the therapeutic properties of this indigenous plant are lacking. As the bark, roots and leaves of C. gratissimus are used separately as well as in combination, this study focused on determining antimicrobial efficacies of the plant parts independently and in combination to assess possible pharmacological interactions (e.g. synergy, antagonism).

Material and Methods

The hydro-distilled leaf essential oil and extracts of bark, root and leaf were comparatively assessed for antimicrobial activity by means of microdilution minimum inhibitory concentration (MIC). The fractional inhibitory concentrations (FIC) were determined for the leaf and root (1:1), bark and root (1:1), leaf and bark (1:1) combination. Isobolograms were plotted to demonstrate interactions between various ratios of the roots and leaves.

Results

The MIC and FIC results indicated variable efficacies for the various plant part combinations, the greatest of which was noted for Cryptococcus neoformans in the root and leaf combination (MIC 0.4 mg/ml and FIC of 0.4). Isobolograms indicated the greatest synergy for Bacillus cereus, Candida albicans and Cryptococcus neoformans.

Conclusion

The observed synergistic interactions clearly indicate that the reductionist approach may often be short-sighted and that biological activity may be improved through combination therapy, where different complex metabolic pools collectively contribute to the enhanced effect.