Proconvulsant effect of khat (Catha edulis) in Sprague dawley rats

Ethnopharmacological relevance

Catha edulis (khat) is a plant whose fresh young leaves are used by an estimated five million people in eastern Africa and the Arabian Peninsula as a drug of recreation. The fresh leaves and shoots are rich in cathinone, a psychostimulant with effects similar to those of amphetamines. Psychostimulants produce a dose-related excitation of the central nervous system which can lead to seizures and convulsions. However there are no reports on studies of the effect of this herb on brain excitability and seizures. This knowledge is useful for doctors who may prescribe drugs whose side effects include lowering seizure threshold because there could be additive proconvulsant effect among khat users.

Aim of the study

to determined whether khat lowers pentylenetetrazole (PTZ) seizure threshold.

Methodology

Male Sprague dawley rats were given fresh aqueous khat extract, old aqueous khat extract (3 g/kg bw), methylphenidate or saline and the timed intravenous (PTZ) seizure threshold test was used to study its effect on seizure threshold.

Results

Fresh khat (3 g/kg) and methylphenidate (4 mg/kg) lowered PTZ seizure threshold.

Conclusion

Khat lowers seizure threshold.     

East African discourses on khat and sex

Aim of the study

The study aims to review and analyse the varied East African discourses on the effects of khat use on libido, fertility, transmission of HIV, prostitution and rape.

Materials and methods

The data were gathered between 2004 and 2009 in Kenya and Uganda. Between 2004 and 2005 across Kenya and Uganda a broad survey approach was adopted, involving identification of and travel to production areas, interviews with producers and consumers in rural and urban settings. In addition, a survey of 300 Ugandan consumers was carried out in late 2004. Between 2007 and 2009, an in-depth study of khat production, trade and consumption was conducted in Uganda. This study also employed a mixture of methods, including key informant interviews participant-observation and a questionnaire survey administered to 210 khat consumers.

Results

Khat is associated, by consumers and its detractors alike, with changes in libido and sexual performance. Although there is no evidence to support their claims, detractors of khat use argue that khat causes sexual violence, causes women to enter sex work, and that chewing causes the spread of sexually transmitted diseases, including the HIV virus.

Conclusions

In East Africa the discourse on khat and sex has led to consumption of the substances being associated by many people with uncontrolled sexual behaviour. There is no evidence that khat use fuels promiscuity, commercial sex, sexually transmitted diseases or rape. The current discourse on khat and sex touches on all these topics. Local religious and political leaders invoke khat use as a cause of what they argue is a breakdown of morals and social order. In Kenya and Uganda it is women khat consumers who are seen as sexually uncontrolled. In Uganda, the argument is extended even to men: with male khat chewers labelled as prone to commit rape.     

The ambiguity of khat in Somaliland

Aim of the study

This article presents an analysis of the economic, political and socio-cultural significance of khat in Somaliland, highlighting both its positive and negative effects.

Materials and methods

Thirteen months of anthropological fieldwork in Somaliland, two months of anthropological fieldwork among Somalis in London, four months experience from the Somalia Joint Needs Assessment working as a development specialist on khat, as well as available and relevant literature.

Results

The recent growth in khat consumption in Somaliland is linked to dispersal, unemployment, socio-cultural changes caused by the civil war, and the massive inflow of remittances. Consumption takes place because of an encouraging socio-cultural environment, few opportunities for education and employment, lack of care and support from parents, as well as widespread availability. Khat represents a significant economic drain on the Somaliland economy, but is also an important source of income for the state and an employment opportunity for thousands. The consumption of khat among government employees challenges the efficiency of state institutions, but also provides a participatory and peaceful political environment that is vital to the democratic transformation of Somaliland. Khat causes the breakdown of families and seriously challenges Somali socio-cultural identities, values and practices. However, khat also strengthens male networks, communities and senses of belonging to Somaliland.

Conclusion

The article argues that khat has both negative and positive effects on Somaliland society. Comparing the role of khat in Somaliland with khat in Puntland and South-central Somalia it is clear that khat in itself does not determine if it contributes to state building and peace, or state failure and violence. Rather, it is the socio-cultural, political and historical context in which it is consumed that determines its larger societal effects. A nuanced analysis of the positive and negative aspects of khat that builds on local perceptions and practices is necessary in order to work with khat from a regulatory and developmental perspective.     

Validity and reliability of a Severity of Dependence Scale for khat (SDS-khat)

Aims of the study

(1) To assess psychological khat dependence and (2) to assess the validity and reliability of the Severity Dependence Scale (Gossop et al., 1995) amended for khat use (SDS-khat), in a sample of UK-resident male adult Yemeni khat chewers.

Materials and methods

A cross-sectional study using a face to face structured interview schedule was conducted amongst purposively sampled UK-resident adult Yemeni male khat chewers, aged 18 years and above, selected during random visits to places of khat sale. A factor analysis with principal components extraction was conducted to explore the construct validity of the proposed SDS-khat. Reliability of the proposed scale was assessed using test-retest and internal reliability tests. The concurrent validity of the proposed SDS-khat was assessed in relation to individual measures and a composite index of khat chewing behaviours using univariate analyses.

Results

Two hundred and four Yemeni male adult khat chewers were interviewed. The mean score of the proposed SDS-khat was 5.52 (SD ±4.03). Forty nine percent of respondents (95% CI = 43-55%) with ≤5 scores were more likely not psychologically dependent. A single factor, uni-dimensional solution identifying the five items making up the scale accounted for 52.33% of variance. The internal reliability was good (Cronbach's alpha coefficient = 0.76) and the test retest intraclass correlation coefficient (ICC) was 0.93 (95% CI = 0.80-0.97). Many individual aspects of the khat chewing were significantly related to the scale. Assessment of the proposed SDS-khat's concurrent validity with individual items of khat chewing identified several significant relationships (p ≤ 0.05) whilst the composite index of khat behaviour also identified a significant relationship (OR = 14.40, 95% CI = 6.71-30.89). The proposed SDS-khat also correlated with self-reported reasons for khat chewing (p ≤ 0.001, OR = 3.54; 95% CI = 1.80-6.96).

Conclusions

In this sample of Yemeni khat chewers the SDS-khat is recommended as a valid and reliable research tool for measuring psychological dependence upon khat. Further validation in other samples is indicated.     

Trauma, khat and common psychotic symptoms among Somali immigrants: A quantitative study

Aim of the study

To investigate the relationship between (i) khat use and (ii) traumatic events, with measures of common psychotic symptoms and symptoms of anxiety and depression. To undertake this work in a Somali population of emigrants who have sought asylum in a non-conflict zone country.

Materials and methods

A secondary analysis of data on a population sample of 180 Somali men and women.

Results

Frequency of khat use was not associated with common psychotic symptoms or with symptoms of anxiety and depression, nor with traumatic events in this population. Traumatic events were related to low levels of psychotic symptoms and high levels of symptoms of anxiety and depression.

Conclusions

Khat use is not inevitably linked to psychotic symptoms in population samples of Somali men and women. The contrasts between these findings and those from studies in conflict zones and studies of people with mental health problems using khat suggest further investigations are necessary. These should take into account environmental and physiological interactions.     

Free radicals are present in human serum of Catha edulis Forsk (Khat) abusers

Objective

Khat (Catha edulis Forsk) is a naturally occurring drug with an amphetamine-like structure and action. It has been postulated that amphetamine induces free radical formation. On this basis, we have hypothesized that Khat may promote synthesis of reactive oxygen and nitrogen species in the same way that amphetamine promotes free radical production.

Materials and methods

Forty male subjects were enrolled in two groups: those with a chronic Khat chewing habit (n = 20), and those without a chewing habit (controls; n = 20). Both groups were matched with regard to age. Total antioxidant capacity and cholinesterase (AChE) activity were assayed.

Results

This study showed that Khat consumption inhibited serum free radical scavenging enzymes, resulting in significant elevations in free radical loads (p = 0.01; n = 20). We also showed that serum acetyl cholinesterase (AChE) was significantly inhibited in the Khat chewing group (p = 0.002; n = 20).

Conclusion

These results show for the first time that Khat may contribute to high levels of free radicals. In addition, the presence of pesticides in Khat leaves is implicated in the inhibition of AChE activity.     

Effect of khat chewing on periodontal pathogens in subgingival biofilm from chronic periodontitis patients

Aims

Existing in vitro and in vivo data suggest that khat may have a favorable effect on periodontal microbiota. The purpose of this study was to assess the effect of khat chewing on major periodontal pathogens in subgingival plaque samples from subjects with chronic periodontitis.

Materials and methods

40 subgingival plaque samples were obtained from periodontitis and healthy sites of 10 khat chewers (40 y median age) and 10 khat non-chewers (37.5 y median age) with chronic periodontitis. Absolute and relative counts of 6 periodontal pathogens were determined in each sample using highly sensitive and specific Taqman real-time PCR assays. Data were analyzed using an ordinal regression model.

Results

Significantly more total bacteria were detected in samples from the periodontitis sites of the khat chewers (OR = 20). Treponema denticola was present at significantly higher absolute counts at the healthy as well as periodontitis sites of the khat chewers (OR = 3.13 and 13, respectively). However, the khat chewers harbored significantly lower absolute counts of Porphyromonas gingivalis at the healthy sites (OR = 0.07). Furthermore, khat chewing was significantly associated with lower relative counts of Porphyromonas gingivalis, fusobacterium ssp., prevotella ssp. and Parvimonas micra-like species in subgingival plaque samples from both healthy and periodontitis sites (OR = 0.11-0.33). Only Treponema denticola was found in higher relative counts at the healthy sites of the khat chewers (OR = 2.98).

Conclusions

Overall, there was a lower burden of pathogens in the khat chewers. Findings from the current study are suggestive of a potential prebiotic effect for khat on periodontal microbiota.     

Khat use and monitoring drug use in Europe: The current situation and issues for the future

Aim of the study

To review the information available on the use of khat (Catha edulis) in the EU, and to assess the future use of this drug and related substances.

Material and methods

Khat is not controlled by international law and it has not been systematically included in the list of illicit drugs monitored in the EU. The current principal source of information on khat use in Europe is the early-warning system set up to monitor new and emerging drugs. Further information was obtained from official national reports to the EMCDDA and from the scientific literature.

Results

Across Europe, the use of khat is low. Khat use is limited to countries with immigrant communities from countries where khat use is common (such as Ethiopia, Somalia and Kenya). Information on the prevalence of khat use in the general population is scarce. Data on seizures provide an insight on the situation, though these may be difficult to interpret. The most recent estimates suggest that Europe accounts for about 40% of the khat seized worldwide.

Conclusion

The shortage of data on the use and patterns of use of khat in Europe does not allow an evaluation of the needs for health and social interventions in communities in which the drug is used. But seizures of the plant are increasing in the EU, and more synthetic derivatives of the pharmacologically active ingredients of the plant (cathine and cathinone) are appearing on the market. Some of these, like mephedrone, have significant potential for future diffusion, and are likely to play a greater role on the European drug scene of the future.     

LC-MS/MS determination and pharmacokinetic study of four lignan components in rat plasma after oral administration of Acanthopanax sessiliflorus extract

Ethnopharmacological relevance

Acanthopanax sessiliflorus (Rupr. et Maxim.) Seem. is a shrub mainly present in China, Japan and Korea, the root bark of which is considered as one of the sources of Wujiapi and widely used for its various pharmacological effects.

Aim of the study

A selective and sensitive UPLC–MS/MS method was developed and validated for the determination and pharmacokinetic study of asarinin, sesamin, helioxanthin and savinin in rat plasma.

Materials and methods

Sample preparation involved a liquid–liquid extraction of the analytes with methyl tert-butyl ether (MTBE). LC separation was achieved on a UPLC C₁₈ column at 30 °C with a mobile phase consisting of methanol–2 mM ammonium acetate (68:32, v/v). The detection was accomplished by multiple-reaction monitoring (MRM) scanning with electrospray ionization (ESI) source operating in the positive ionization mode. The optimized mass transition ion-pairs (m/z) monitored for asarinin, sesamin, helioxanthin, savinin and IS were 372.2/233.0, 372.2/233.0, 349.1/319.0, 352.9/334.9 and 180.0/109.7, respectively.

Results

The current LC–MS/MS assay was validated for linearity, intra-day and inter-day precisions, accuracy, extraction recovery and stability and was suitable for pharmacokinetic studies of the four lignans after oral administration of Acanthopanax sessiliflorus extract. The time to reach the maximum plasma concentration (T_max) was 2.50 ± 0.15 h for asarinin, 1.94 ± 0.28 for sesamin, 2.22 ± 0.48 h for helioxanthin and 2.83 ± 0.29 h for savinin. The elimination half-time (t_1/2) of asarinin, sesamin, helioxanthin and savinin was 6.08 ± 1.10, 11.69 ± 0.50, 7.16 ± 0.52 and 6.26 ± 0.57 h, respectively.

Conclusion

This paper described a simple, sensitive and validated UPLC–MS/MS method for simultaneous determination of four lignans in rat plasma after oral administration of Acanthopanax sessiliflorus extract, and investigated on their pharmacokinetic studies as well.     

Cerebral protection of purified Herba Leonuri extract on middle cerebral artery occluded rats

Aim of study

Oxidative stress is involved in stroke. In particular, Chinese Herbal Medicine with antioxidant properties is believed to have potential therapeutic effect. In this study, neuroprotective effects of purified Herba Leonuri (pHL) were evaluated in Wistar rats undergone middle cerebral artery occlusion (MCAO).

Materials and methods

The rats were treated with their respective treatments for 2 weeks prior to the MCAO, continually treated for another 7 days after MCAO. During the post-surgery treatment period, neurological deficit score was measured. At the end of treatment, animals were sacrificed and samples were collected for analysis of infarct volume, apoptosis and antioxidant analysis.

Results

Under the treatment of pHL, the infarct volume was reduced significantly from 20.75 ± 0.03% to 15.19 ± 0.02% (p < 0.05). The neurological impairment was alleviated to 1.82 as compared to vehicle (2.43). Plasma antioxidant concentration was increased from 0.31 ± 0.03 mM to 0.42 ± 0.05 mM (p < 0.05). DNA oxidative damage was reduced to 1.19 ± 0.03 in stroke pHL treated group (p < 0.05 as compared to vehicle group, 1.78 ± 0.03). pHL could reduce the level of apoptosis and also the pro-apoptotic proteins, but increase the level of anti-apoptotic proteins.

Conclusion

pHL is believed to have promising therapeutic effect for stroke treatment through antioxidant mechanisms.     

Khat (Catha edulis) and ethanol co-dependence modulate seizure expression in a pentylenetetrazol seizure model

Ethnopharmacological relevance

Khat is a plant with psychostimulant properties whose parts, mainly leaves and twigs, are chewed for its euphoriant effects. Khat use and ethanol abuse are increasingly becoming global health concerns especially among many disadvantaged social groups. The present studies were undertaken to investigate seizure susceptibility and responses following chronic co-administration of khat and ethanol.

Materials and methods

Juvenile male Sprague-Dawley (SD) rats were administered khat, ethanol or combined khat and ethanol twice daily for 28 days by gavage. Khat-treated animals received 2 g/kg or 4 g/kg body weight continuously for the study period. Ethanol-treated animals received 20% ethanol at a dose of 4 g/kg body weight. The convulsant, pentylenetetrazol (PTZ), was administered intraperitoneally at a dose of 40 mg/kg body weight. Seizure responses were recorded.

Results

Twice-daily dosing of khat did not produce inhibition of weight gain. Khat alone, combined khat and 20% ethanol, but not 20% ethanol alone, significantly reduced the latency to seize. Khat treatment at 2 g/kg but not 4 g/kg body weight also significantly increased the duration of seizures. Conversely, combined khat and ethanol reduced the duration of seizures compared to controls. Ethanol alone reduced the seizure severity while khat alone, and combined khat and ethanol, produced close to the maximum seizure severity.

Conclusions

These data suggest that combined moderate to high dose khat and ethanol co-dependence produce a greater deleterious CNS effect than either drug alone. Future studies will address neurochemical effects, in addition to neuroadaptations, resulting from coabuse of these drugs.     

γ-Sitosterol from Acacia nilotica L. induces G2/M cell cycle arrest and apoptosis through c-Myc suppression in MCF-7 and A549 cells

Ethnopharmacological relevance

Acacia nilotica is widely distributed in Asia. In India, it occupies an important place in the indigenous system of medicine against anti-inflammatory, antioxidant, cancers, and/or tumors.

Aim of the study

The purpose of this study is to investigate the inhibitory effect of Acacia nilotica leaves extract and γ-Sitosterol on cell proliferation, the apoptotic effect and cell cycle arrest in breast and lung cancer cells.

Materials and methods

GC–MS and HPLC were used to determine the chemical constituents of this extract and γ-Sitosterol respectively. Human MCF-7 and A549 cell lines were treated with Acacia nilotica extract and γ-Sitosterol. Cell viability was determined by MTT assay. Cell proliferation was determined by BrdU incorporation assay. Apoptosis was detected by cell morphologic observation through AO/EtBr staining, cell cycle analysis, and immunoblot analysis on the expression of protein associated with cell cycle arrest.

Results

Experimental results of bioactive compound analysis indicate that γ-Sitosterol, bioactive ingredients of Acacia nilotica extract. The IC₅₀ value of extract on MCF-7 and A549 cancer cells was 493.3 ± 15.2 and 696.6 ± 11.5 μg/ml, respectively. Acacia nilotica extract and γ-Sitosterol were inhibited the cell proliferation by 54.34 ± 1.8 and 42.18 ± 3.9% for MCF-7 and 58.26 ± 1.5 and 44.36 ± 3.05% for A549 cells. The percentage of apoptotic cells observed in the MCF-7 and A549 cell lines were increased to 42.46 and 36.8% of extract; 46.68 and 43.24% for γ-Sitosterol respectively. Flow cytometric analysis results demonstrate that cells were arrested at the G2/M phase and decrease the c-Myc expression.

Conclusions

This study demonstrates in vitro results, which support the ethnomedical use of γ-Sitosterol against cancer. Experimental results of this study suggest that γ-Sitosterol exerts potential anticancer activity through the growth inhibition, cell cycle arrest and the apoptosis on cancer cells.     

Effects of traditional Chinese medicine on bone remodeling during orthodontic tooth movement

Ethnopharmacological relevance

Dipsacus asper Wall (Dipsacaceae), Salvia miltiorrhiza (Salvia) and Drynaria fortunei (Drynaria) have been traditionally used in Chinese medicine as the main ingredient of many formulations for the treatment of cardiovascular and inflammatory diseases.

Aim of the study

This study was aimed to evaluate the effect of the traditional Chinese medicine (TCM) Dipsacaceae, Salvia and Drynaria on bone remodeling during orthodontic tooth movement (OTM).

Setting

This study was conducted in School of Stomatology, Shandong University between 2009 and 2010 [Jinan, Shandong, China].

Materials and methods

Ninety-six eight-week-old female SPF Wistar rats 180–200 g were selected and randomly divided into four groups of 24: Dipsacaceae group, Salvia group, Drynaria group and control group. Animal models for orthodontic tooth movement were then established which consisted of a closed coil spring ligated to the upper first molar and incisors, exerting a force of 40 g during the experimental period. Rats in the TCM groups were given Dipsacaceae, Salvia and Drynaria decoction respectively by intragastric administration 6 g/kg/day and the control group were given normal saline 3 ml. The rats were sacrificed in batch on the 7th, 14th, 21st and 28th days after orthodontic treatment. Slices from periodontium of the upper first molar were observed under optical microscope. Neovascularization, new bone formation and osteoclast number were observed.

Results

The upper first molars were drawn mesial by the force. Telangiectasia and new bone formation in periodontal tissue were significantly in the TCM groups compared with the control group. Application of orthodontic forces in the experimental teeth showed a significant increase (P < 0.05) of osteoclast number in the TCM group when compared with the control group. In addition, the number of osteoclast had no significant differences among the TCM groups (P > 0.05). Osteoclast number in the TCM group and the control group were 10.12 ± 0.058, 10.13 ± 0.022, 10.09 ± 0.047 and 9.55 ± 0.045, respectively.

Conclusions

These findings suggest that the TCM decoction are beneficial to the alveolar bone remodeling by promoting osteoclast differentiation during OTM.     

Isolation of gentiopicroside from Gentianae Radix and its pharmacokinetics on liver ischemia/reperfusion rats

Ethnopharmacological relevance

Gentiopicroside (GPS) is a secoiridoid glucoside isolated from the ethanol extract of Gentianae Radix with a content of 13%, which has been used for centuries in Chinese as a digestive aid.

Aim of the study

This study investigates the pharmacokinetics of GPS and its metabolic pathway for the liver ischemia/reperfusion (I/R) in rats.

Materials and methods

The experimental animals were anesthetized intraperitoneally (i.p.) with a mixture of urethane (1.0 g/kg) and α-chloralose (0.1 g/kg). A midline laparatomy was performed and the liver hilum was gently exposed. All structures in the portal triad (hepatic artery, portal vein, and bile duct) to the left and median liver lobes were occluded with silk thread for 30 min. Ischemia was followed by a sudden reperfusion after removing the occluding threads. After 60 min reperfusion, the rats received a single intravenous 5 mg/kg dose of GPS.

Results

The area under concentration curve (AUC) was significantly increased; however, the clearance (Cl) was significantly decreased in the liver I/R rats. Furthermore, after pretreated with SKF-525A (50 mg/kg, i.p.), a cytochrome P450 (CYP) inhibitor, AUC, elimination half-life (t_1/2) and the mean residence time (MRT) of GPS in rat blood were significantly increased, suggesting that CYP was involved in the metabolism of GPS. For the group without liver I/R, GPS was administered at doses of 5 mg/kg and 100 mg/kg intravenously and orally, respectively. The pharmacokinetic results indicated that the AUC was 565 ± 95.1 and 1163 ± 273 min μg/mL and the t_1/2 of GPS was 71 ± 9 and 106 ± 17 min after intravenous and oral administration, respectively. The oral bioavailability of GPS was 10.3 ± 2.4% in the rats.

Conclusions

The status of I/R might prolong the disposition of GPS, and the plasma concentration of GPS in the liver I/R injury rats was significantly increased. The increased body exposure of GPS in the treatment of liver I/R may result from the decreased metabolism of GPS mediated by CYP in the liver.     

Anti-inflammatory effect of triterpene 3β, 6β, 16β-trihydroxylup-20(29)-ene obtained from Combretum leprosum Mart & Eich in mice

Ethnopharmacological relevance

The 3β, 6β, 16β-trihydroxylup-20(29)-ene (TTHL) is a pentacyclic triterpene obtained from a medicinal plant named Combretum leprosum. In folk medicine, this plant is used to treat several diseases associated with inflammation and pain. We previously demonstrated that TTHL presents a significant antinociceptive effect, suggesting the involvement of the glutamatergic system.

Aim of the study

This study was designed to investigate the effect of TTHL on nociception and vascular permeability induced by acetic acid. We also evaluated the effect of TTHL on carrageenan-induced peritonitis and the levels of cytokines (interleukin 1-β [IL-1β], tumor necrosis factor α [TNF-α] and interleukin 10 [IL-10]) on peritoneal fluid.

Materials and methods

TTHL was administered orally by intra-gastric gavage (i.g.) 60 min prior to experimentation. Abdominal contractions and vascular permeability were induced by an intraperitoneal (i.p.) injection of acetic acid (0.6%). We also investigated whether TTHL decreases carrageenan-induced peritonitis (750 μg/cavity) by measuring leukocyte migration and vascular permeability. In addition, we evaluated the effects of TTHL on TNF-α, IL-1β and IL-10 release induced by carrageenan on peritoneal fluid. The levels of these cytokines were measured by ELISA.

Results

TTHL (0.01–10 mg/kg) administered by intra-gastric (i.g.) gavage inhibited (69±3%) acetic acid-induced abdominal constrictions, with an ID₅₀ of 0.15 (0.03–0.8) mg/kg. TTHL (10 mg/kg) also reduced the leukocyte infiltration induced by acetic acid, with an inhibition of 59±9 but had no effect on abdominal vascular permeability. In addition, indomethacin (10 mg/kg, i.p.) reduced the nociceptive behavior (92±1%), total leukocyte migration (29±3%) and capillary permeability (71±3%) induced by acetic acid. While the glucocorticoid dexamethasone (2 mg/kg, s.c.) reduced partially but significantly the nociception (31±1%), besides to promote a marked reduction on total leukocyte migration (60±2%) to the peritoneal cavity caused by acetic acid. In a model of peritonitis induced by carrageenan, TTHL also reduced total leukocyte migration, mainly neutrophils (inhibition of 84±3% and 85±2% at 30 mg/kg and 100 mg/kg, respectively). Likewise, dexamethasone (0.5 mg/kg, i.p.) resulted in an inhibition of 93±3%. Nevertheless, carrageenan-induced abdominal vascular permeability was reduced by dexamethasone but was not altered by TTHL. Furthermore, dexamethasone and TTHL significantly reduced the TNF-α and IL-1β levels in peritoneal fluid, whereas the IL-10 levels were unchanged.

Conclusions

Altogether, our data confirm the antinociceptive effect of TTHL and demonstrate its effect in inflammatory animal models, providing novel data about this compound, which could be useful as an anti-inflammatory drug.     

Effect on blood pressure of a dietary supplement containing traditional medicinal plants of Côte d'Ivoire

Ethnopharmacological relevance

A medicinal composition containing salt (sodium chloride) is given as a traditional dietary supplement to hypertensive patients (TDSHP) in Côte d’Ivoire. It consists of whole plant of Bidens pilosa (Asteraceae) and fresh leaves of Moringa oleifera (Moringaceae).

Aim of the study

The aim of this study was to establish the scientific basis for the use of this traditional recipe rich in sodium chloride in hypertension settings.

Materials and methods

We used a total aqueous extract of this traditional dietary supplement containing medicinal plants (Bidens pilosa, Moringa oleifera) and salt (sodium chloride). Experiment was carried out to evaluate its effect on arterial blood pressure of rabbits. The experimental device used for recording blood pressure in rabbits is based on the principle of Ludwig mercury manometer.

Results

TDSHP between 5 × 10⁻⁸ and 5 × 10⁻² mg/kg caused a dose-dependent hypotension. TDSHP elicited drops in blood pressure ranging between 7.14 ± 4 and 100 ± 7.5%, compared to normal blood pressure of rabbits. Fifty percent effective dose of TDSHP was 3.95 × 10⁻⁴ mg/kg. Similarly as the hypotension induced by acetylcholine, the one caused by TDSHP at dose of 3.95 × 10⁻⁴ mg/kg in rabbit was progressively inhibited by atropine, dosed between 5 × 10⁻⁴ to 5 × 10⁻² mg/kg. The percentage drop of recorded blood pressure ranged from 50.3 ± 1.87 to 3.71 ± 1.09% compared to the normal value of blood pressure. In the presence of atropine, TDSHP effect was partially inhibited. The same increasing doses of TDSHP reduced significantly the increase of blood pressure induced by adrenaline dosed at 4.76 × 10⁻⁴ mg/kg from 89.3 ± 2.19 to 1.19 ± 0.59%.

Conclusion

The consumption of this traditional dietary supplement is justified in hypertensive patients according to its composition and its ability to reduce blood pressure has been demonstrated experimentally. TDSHP should not be considered as an antihypertensive drug, it remains to us a salt substitute to be taken with moderation with strict adherence to the traditional dose.     

In vitro anti-prostate cancer and ex vivo antiangiogenic activity of Vernonia guineensis Benth. (Asteraceae) tuber extracts

Ethnopharmacological relevance

Prostate cancer is a major problem worldwide and affects most men above the age of forty-five. Vernonia guineensis Benth. (Asteraceae) root decoction is used in folk medicine in Cameroon to treat a number of ailments including prostate cancer. The aim of this study was to provide a preliminary validation of the use of Vernonia guineensis Benth. extracts to treat prostate cancer by evaluating the in vitro activity of its crude extracts and isolated molecules on prostate cancer cells lines and effect on angiogenesis which is essential for growth and metastases of prostate cancer.

Materials and methods

Aqueous, dichloromethane and methanol extracts of Vernonia guineensis Benth. tubers were tested for activity against three prostate cancer cell lines (PC-3, DU-145 and AT3B-1). The dichloromethane extract was subjected to bioactivity guided fractionation. Anti-proliferation, clonogenic and antiangiogenic activity of the crude extracts and isolated compound were tested. The WST-1 assay was used for the anti-proliferation activity meanwhile the standard clonogenic test and the rat ring aorta assay were carried out to determine the clonogenic and antiangiogenic activity of tested products respectively.

Results

The aqueous and methanol extracts of Vernonia guineensis Benth. demonstrated weak activity against prostate cancer cell lines in vitro with IC₅₀ > 100 μg/mL. The dichloromethane extract was more potent with IC₅₀ of 56.233 ± 3.630 μg/ml and 67.316 ± 2.452 μg/ml against the DU-145 and PC-3 cell lines respectively. Activity guided fractionation of this extract yielded a Pentaisovalerylsucrose (1) isolated for the first time from a natural source to the best of our knowledge. Compound 1 demonstrated in vitro activity against the human prostate cancer cell lines PC-3 and DU-145 with IC₅₀ of 5.701 ± 0.142 μM and 4.275 ± 0.710 μM, respectively. The IC₅₀ of the compound was 5.763 ± 0.425 μM against AT3B-1, a rat prostate cancer cell line expressing P-glycoprotein which is linked to drug resistance in most metastatic cancers. Compared to compound 1, Paclitaxel and Docetaxel were active against AT3B-1 at 2.641 ± 1.253 μM and 0.613 ± 0.251 μM. Paclitaxel showed IC₅₀ values of 0.004 ± 0.002 μM and 0.003 ± 0.001 μM against DU-145 and PC-3 prostate cancer cell lines respectively. Docetaxel showed IC₅₀ values of 0.002 ± 0.001 μM and 0.004 ± 0.001 μM against DU-145 and PC-3 prostate cancer cell lines respectively.

Conclusion

The in vitro anti-prostate cancer and the antiangiogenic activity of Vernonia guineensis Benth. extracts and isolated compound support the use of the tubers of this plant for the treatment of prostate cancer.     

Preventive and curative effect of Trigonella foenum-graecum L. seeds in C57BL/6J models of type 2 diabetes induced by high-fat diet

Ethnopharmacological relevance

Trigonella foenum-graecum L. (TFG) is traditionally used to treat diabetes in North Africa. we therefore tested the effects of the hydro-alcoholic extract of TFG seeds in a C57/BL6J mouse model of diabetes induced by a standardised high-fat diet (HFD).

Materials and methods

Plant extracts (2 g/kg daily) were administered orally by gavage at the start of HFD, or after confirmation of established diabetes (17th week), for 20 or 18 weeks, respectively, to male C57BL/6J mice. Animals were weighed; food intake and plasma glucose, lipid profile, insulin and insulin resistance were measured.

Results

TFG extracts opposed the development of diabetes: compared with untreated HFD mice, TFG-treated HFD mice had lower mean (±SD) plasma glucose (129.3±39.4 vs. 183.1±19.1 mg/dL, p<0.05), plasma insulin (1.3±0.8 vs. 3.1±1.8 ng/mL, p<0.05) and triglycerides (18.9±12.9 vs. 48.9±12.1 mg/dL, p<0.05), and less insulin resistance as estimated by the homeostasis model assessment (HOMA: 9.7±11.1 vs. 38.3±26.6, p<0.05). In mice with established diabetes, TFG reduced fasting plasma glucose (170.4±24.1 vs. 229.0±20.8 mg/dL, p<0.05), plasma insulin (1.7± 1.3 vs. 3.3±14.3 ng/mL, p<0.05) and insulin resistance (HOMA: TFG: 19.2±15.7 vs. HFD control: 38.5±30.3, p<0.05). In addition, administration of TFG extract also caused significant reduction in triglycerides (17.9±9.7 vs. 62.8±18.3 mg/dL, p<0.05) and total cholesterol (1.30±0.20 vs. 1.80±1.10 g/L, p<0.05), and an increase in HDL-cholesterol (1.6±0.2 vs. 1.2±0.1 g/L). The plant extract had no effect on calorie intake or body weight.

Conclusion

TFG extract opposed the development of experimental HFD diabetes in mice, and had an anti-diabetic effect in mice with established diabetes.     

Hyperpigmentant activity of leaves and flowers extracts of Pyrostegia venusta on murine B16F10 melanoma

Ethnopharmacological relevance

Pyrostegia venusta is a native Brazilian plant which has a variety of uses in traditional folk medicine including the treatment of vitiligo. However, its effectiveness on melanogenesis is not yet elucidated.

Aim of the study

This study aimed to investigate the melanogenic activity of hydroalcoholic extracts from the leaves and flowers of P. venusta on murine B16F10 melanoma cells.

Materials and methods

Different concentrations of the hydroalcoholic extracts of flowers and leaves of P. venusta were evaluated in trials of spontaneous melanin content (4 days), and cell viability by the MTT assay in murine B16F10 cells, and in the mushroom tyrosinase activity in vitro.

Results

Both extracts, leaves (0.1; 0.3; 1 and 3 μg/mL) and flowers (0.03 and 0.1 μg/mL) increased the melanin content in a concentration dependent manner after 4 days of incubation on melanoma cells. Leaves extract promoted enhancement of melanogenesis with maximum effect of 33.3 ± 3% (3 μg/mL), and the flower extract increased in 23.4 ± 3% (0.1 μg/mL). The cell viability test using MTT showed that in the same tested concentrations of both extracts no cell death was detected. Actually, either extract was not able to cause any change in the tyrosinase activity. HPLC analysis of P. venusta extracts found 0.09% and 1.08% of allantoin on leaves and flowers extracts, respectively.

Conclusions

The leaves and flowers extracts of P. venusta stimulates B16F10 melanogenesis at very low concentrations. These findings support the folk medicinal use of P. venusta on the treatment of hypopigmentation diseases, such as vitiligo.