Antinociceptive and antiinflammatory effects of essential oil of Dennettia tripetala G.Baker (Annonaceae) in rodents

Chemical composition and healing potential of essential oil of Dennettia tripetala on methicillin-resistant Staphylococcus aureus: infected wound model

Background

Dennettia tripetala (Pepperfruit) is an important medicinal plant in some West African communities. This study was designed to examine the antibacterial properties and wound-healing abilities of D. tripetala essential oil on mice with methicillin-resistant Staphylococcus aureus (MRSA) infections. Gas chromatography-mass spectrometry (GC–MS) was used to analyse the essential oil (EO) extracted by hydro-distillation from the dried fruits of D. tripetala. MRSA was identified using 30 µg cefoxitin disk, CHROMagar, and Polymerase Chain Reaction. Congo red agar and tube technique were used to assess the production of biofilms. The antimicrobial susceptibility for both antibiotics and essential oil was determined by Kirby Bauer and broth dilution methods. Eleven male mice were used in the invivo study, and each animal had wound infection on the dorsal inter-scapular skin region created with a 6 mm biopsy punch and 50 μl (adjusted to 0.5 McFarland standard) of MRSA. The size of the wound and its histological characteristics were used to estimate healing rate.

Results

The GC–MS investigation of the essential oil revealed six compounds, with benzene (2-nitroethyl) being the most prominent. Out of the eighteen (18) isolates examined, 12 MRSA strains were identified using the three methods for methicillin resistance determination, with about 80% of them being classified as biofilm producers. More than 60% of the MRSA isolates were resistant to erythromycin, fusidic acid, gentamicin and trimethoprim/sulfamethoxazole. The essential oil had greater antibacterial activity than the reference antibiotic, vancomycin. The essential oil had a minimum inhibitory concentration of 80 l/ml and a minimum bactericidal concentration of 160 l/ml (v/v). Haematoxylin and eosin staining revealed that the skin tissue that had been exposed to D. tripetala essential oil had a thicker epithelial layer, numerous fibroblasts, a build-up of collagen, and many blood cells.

Conclusions

The results showed that D. tripetala essential oil has powerful anti-staphylococcal properties as well as the capacity to expedite wound healing. This suggests that D. tripetala essential oil could be a successful candidate for developing a topical agent for wound management.

Phospholipids modifications, genotoxic and anticholinesterase effects of pepper fruit (Dennettia tripetala G. Baker) extract in Swiss mice

The toxicity of D. tripetala fruit extract to mice was investigated using data obtained from lipidomic analyses, comet and Acetylcholinesterase (AChE) assays. Mice (n = 8) were exposed for 30 days via oral gavage to vehicle (5% Tween 80) (negative control), D. tripetala extract (100, 200 and 400 mg/kg) and 40 mg/kg methyl methanesulfonate (MMS) (positive control). The profile of compounds in the fruit extract was analyzed using gas chromatography-mass spectrometry. Out of the total of 32 compounds identified, considerable amount of established insecticidal compounds such as 2-phenylnitroethane, cis-vaccenic acid, linalool and linoleic acid were detected. Fruit extract did not induce DNA damage relative to negative control. Percentage gain in body weights differed significantly across the four weeks. Significantly highest and lowest brain AChE activity was observed in animals exposed to 200 and 400 mg/kg D. tripetala, respectively. Fruit extract modulated the brain phospholipid profile due to significant fold changes of 48 lipid species out of the total of 280 lipid species. High number of differentially expressed phosphatidylcholine (PC) species and significant levels of phosphatidylethanolamine (PE) at 400 mg/kg suggests that activation of inflammation and methylation pathways are the most plausible mechanisms of D. tripetala toxicity to mouse brain tissue.

Dennettia tripetala Relieves Chronic Hepatorenal Injuries in Rats by Altering fas, sod-1, and tnf-α Expression

The effectiveness of Dennettia tripetala extracts was compared to that of the standard drug, silymarin, in reducing chronic liver and kidney anomalies. Male albino Wistar rats were grouped in tens. Carbon tetrachloride was dissolved in olive oil (1:4) and administered to specific groups at a dose of 3 mL/kg body weight (bw) twice a week for six weeks. From week five, the extracts and silymarin were administered in distilled water daily for two weeks at doses of 250 mg/kg bw and 6 mg/kg bw, respectively, to specific groups. All administrations were carried out using a gavage, with appropriate controls. These results showed that the plant extracts decreased the serum activity of liver marker enzymes, restored the liver and serum lipid profiles as well as serum protein profile, reduced serum, urea, and creatinine, and restored superoxide dismutase and catalase activities in the liver and kidneys, which carbon tetrachloride had altered. The extracts also decreased steatosis and centriole congestion in the liver as well as necrosis and structural damage in the kidneys, which carbon tetrachloride caused, and the extracts proved to be as potent as silymarin. The extracts also decreased the expression of fas (P<0.05), sod-1 (P<0.05), and tnf-α (P>0.05) in the liver, which carbon tetrachloride had increased. Conclusively, D. tripetala reduced chronic liver and kidney damage induced by carbon tetrachloride; it reduced the expression of fas, sod-1, and tnf-α in the liver to levels similar to that of the control group, and it was as effective as silymarin.

Essential Oils of the Leaf and Stem of Polyalthia viridis Craib and Their Biological Activities

Plants of the genus Polyalthia can be seen as a rich resource of essential oils type terpenoids. In this study, the essential oils obtained by hydro-distillation from the leaf and stem of Polyalthia viridis were analysed by gas chromatography/mass spectrometry–flame ionization detection. Thirty-nine constituents (95.3%) were identified in the leaf oils and 42 constituents (90.9%) in the stem oils. Sesquiterpene hydrocarbons and oxygenated sesquiterpenes were the main constituents of both oils, in which 2 sesquiterpene hydrocarbons, germacrene D (45.1%-47.4%) and bicyclogermacrene (8.2%-17.1%), were the 2 major compounds. The stem oils inhibited the growth of 3 cancer cell lines, HepG2, MCF7, and A549, with half inhibitory concentration (IC50) values of 56.7 to 68.4 μg/mL. The stem oils also successfully suppressed the growth of the filamentous fungus Aspergillus niger and the yeast Candida albicans with minimum inhibitory concentration values of 50 μg/mL. P viridis oils suppressed NO production in lipopolysaccharide-stimulated BV2 microglial cells, with IC50 values of 57.6 to 76.7 μg/mL.

In vivo and in silico studies of Dennettia tripetala essential oil reveal the potential harmful effects of habitual consumption of the plant seed

Dennettia tripetala G. Baker (Annonaceae), is a plant with nutritional, social economy, and medicinal values. Its rising medicinal profile makes this plant a prospect in drug discovery. However, the reported strong addictive potential among habitual consumers makes the need to establish its safety imperative. In this report, we evaluated the safety profile of the essential oil of the seed of D. tripetala (EODS) in nulliparous female Wistar rats using in vivo single and repeated dose toxicity profiling, as well as in silico toxicity profiling of its known seed oil derived phytoconstituents. Our results showed consistent significant dose-dependent alterations in relative body weights, organ-body and organ-brain weight ratios, haematological and biochemical indices, as well as liver and kidney histoarchitectures, following single and repeated oral administrations. Significant alterations in liver and kidney histoarchitectures were consistent with the observed significant increase in AST/ALT ratio, suggesting deleterious effects of EODS on the kidney and liver. However, the lack of alterations in the histoarchitectures of the hippocampus and hypothalamus suggests that the brain may not have been adversely affected. Also, the in silico analysis suggests that hepatotoxic effects of EODS may be linked to Benzylnitrile, Humulene, Linalool, (Z)-ß-Ocimene. In addition, the failure of ß-Phenylnitroethane, the most abundant phytoconstituent of EODS, to pass phases I and II in silico toxicity screening, and the presence of Caryophyllene oxide, a known toxic compound, coupled with the predicted binding of both to DNA and protein, low LD50 and high percent mortality at 250 mg/kg of repeated doses, further confirmed the potentially toxic nature of EODS. We concluded that based on our in vivo and in silico observations, there is an urgent need for public education to regulate the excessive consumption of the seeds of D. tripetala.

Preliminary toxicology profile of Dennettia tripetala (Pepper Fruit) methanolic leaves extract

Background

Dennentia tripetalla (Pepper Fruit) belongs to the Annonaceae family and is abundant in Nigeria. Its fruit in folklore medicine is used for treatment of varying ailments. While ample research evidence exists on the plants fruit and seed, no current study exists on the toxicological profile of the plant leaves.

Methods

qualitative and quantitative phytochemicals and In vitro antioxidant assays were carried out using standard methods. The acute toxicity study indicates that the LD50 was higher than 2000 mg/Kg body weight. Sub-chronic toxicity studies was carried out using five groups of rats. Group 1 served as control, 2–5 received 100 mg/Kg, 200 mg/Kg, 500 mg/Kg and 1000 mg/Kg body weight orally for 28 days.

Results

Post-administration biochemical analysis indicates there was increased weight in rats administered 100 mg/kg and 200 mg/kg while it reduced in the 500 mg/kg group. Significant elevations of liver function markers were reported for 200 mg/kg and 500 mg/kg respectively. Serum and hepatic protein profiles remained unaltered. Renal function analysis revealed elevated serum urea and creatinine for 200 and 500 mg/kg groups, elevated serum Na+ and Ca+ and reduced serum Cl− for the 500 mg/Kg group. Elevated Kidney K+ and Ca+ levels, reduced Cl− were significantly observed in 500 mg/Kg group. Significant rise in hepatic and renal lipid peroxidation was observed in 200 and 500 mg/Kg groups. There were observed disarmament of the antioxidant defense systems occasioned by rise and drop in tissue (hepatic, renal, testes, heart) Superoxide dismutase (SOD), Catalase (Cat), Glutathione-s-transferase (GST), Glutathione peroxidase (GPx) activities in the test groups relative to control. Histopathological examination indicated architectural aberrations at 500 and 1000 mg/kg.

Conclusions

It concluded that the plant had significant phytochemical and antioxidant properties of medical interest and possessed toxic properties in rats when administered at a dose above 200 mg/Kg over a prolonged period of time.

Phytochemical screening of aqueous leaf extract of Blighia sapida K.D. Koenig (Sapindaceae) and its analgesic property in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Blighia sapida is traditionally used in treating intercostal pain, psychosis, stomach ache, back pain, and skin diseases. However, there is limited information on the scientific basis for its use traditionally in the treatment of pain.

AIM OF STUDY

To identify the major constituents in the aqueous leaf extract of Blighia sapida (AEBS) and to assess its analgesic properties in mice.

MATERIALS AND METHODS

Bioactive compounds were identified and quantified in AEBS by High Performance Liquid Chromatography/Photodiode Array Detector (HPLC/DAD). Analgesic activity of AEBS was assessed at doses of 125, 250, and 500 mg/kg p.o., using animal models.

RESULTS

Chlorogenic acid, saponins, tannins, caffeic acid, quercetin, gallic acid, pyrogallol, quinine, caffeine, and nicotine were identified. At doses 250 mg/kg (p < 0.05) and 500 mg/kg (p < 0.01), AEBS significantly inhibited acetic acid induced writhing in comparison with the control. It also significantly inhibited pain in the inflammatory phase of the formalin induced paw licking test at 250 mg/kg (p < 0.01) and 500 mg/kg (p < 0.05) doses, in comparison with the control. It did not inhibit pain in the neurogenic phase of the formalin paw licking and in the hot plate tests.

CONCLUSION

Blighia sapida leaf extract possesses analgesic activity that is mediated by peripheral mechanisms but not through central mechanisms.

Memory enhancing, anticholinesterase and antimicrobial activities of β-phenylnitroethane and essential oil of Dennettia tripetala Baker f

ETHNOPHARMACOLOGICAL RELEVANCE

Dennettia tripetala Baker f. belonging to the family Annonaceae is an important food and medicinal plant used in some local communities in Southwest Nigeria.

AIMS OF THE STUDY

The study aims at determining the chemical composition of the essential oil of different morphological parts of D. tripetala, the memory enhancing and anticholinesterase activities as well as the antimicrobial properties.

MATERIALS AND METHODS

Essential oil of the morphological parts namely the fresh fruits, dried fruits, dried seeds and fresh leaves were obtained by hydrodistillation and analysed by GC-FID and GC-MS. The oil samples were evaluated for memory enhancement using Y-maze and in vitro anticholinesterase activities. The antimicrobial properties were also evaluated by nutrient broth method.

RESULTS

GC analysis identifies β-ocimene, linalool, β-phenylnitroethane and humulene as common constituents of the fresh fruits, dried fruits, dried seeds and fresh leaves. β-Phenylnitroethane (BPNE) was the predominant constituent of all the parts; with the dried seed containing 87.4% BPNE, followed by the dried fruit (78.1%), fresh leaf (62.9%) and the fresh fruit content was 61.6%. The second most predominant constituent, linalool, was highest in the fresh fruit (29.9%), followed by the fresh leaf (16.0%), the dried fruit (14.9%) and the dried seed had least linalool content (8.8%). (Z)- β-Ocimene and humulene were other common components. The seed oil and BPNE exhibited high memory enhancing activities in the Y-maze test. However, the seed oil exhibited the best inhibition against the test bacteria and it had a broad spectrum of antimicrobial activity. Bioactivities demonstrated by the various essential oils were not solely due to BPNE; rather, synergistic effects of other components are quite obvious.

CONCLUSION

The most abundant component - β-phenylnitroethane of D. tripetala was totally responsible for its memory enhancing properties but could not solely account for its antimicrobial activity.

An Investigation of Potential Sources of Nutraceuticals from the Niger Delta Areas, Nigeria for Attenuating Oxidative Stress

Background: Diets rich in fruits, vegetables, and medicinal plants possess antioxidants potentially capable of mitigating cellular oxidative stress. This study investigated the antioxidant, anti-acetylcholinesterase (AChE), and total phenolic and flavonoids contents (TPC/TFC) of dietary sources traditionally used for memory enhancing in Niger Delta, Nigeria. Methods:Dacroydes edulis methanolic seed extract (DEMSE), Cola lepidota methanolic seed extract (CLMSE), Terminalia catappa methanolic seed extract (TeCMSE), Tricosanthes cucumerina methanolic seed extract (TrCMSE), Tetrapleura tetraptera methanolic seed extract (TTMSE), and defatted Moringa oleifera methanolic seed extract (DMOMSE); Dennettia tripetala methanolic fruit extract (DTMFE), Artocarpus communis methanolic fruit extract (ACMFE), Gnetum africana methanolic leaf extract (GAMLE), Musa paradisiaca methanolic stembark extract (MPMSE), and Mangifera indica methanolic stembark extract (MIMSE) were evaluated for free radical scavenging antioxidant ability using 2,2-Diphenyl-1-picrylhydrazyl (DPPH), reducing power capacity (reduction of ferric iron to ferrous iron), AChE inhibitory potential by Ellman assay, and then TPC/TFC contents determined by estimating milli-equivalents of Gallic acid and Quercetin per gram, respectively. Results: The radical scavenging percentages were as follows: MIMSE (58%), MPMSE (50%), TrCMSE (42%), GAMLE (40%), CLMSE (40%), DMOMSE (38%), and DEMFE (37%) relative to β-tocopherol (98%). The highest iron reducing (antioxidant) capacity was by TrCMSE (52%), MIMSE (40%) and GAMLE (38%). Extracts of MIMSE, TrCMSE, DTMFE, TTMSE, and CLMSE exhibited concentration-dependent AChE inhibitory activity (p < 0.05–0.001). At a concentration of 200 µg/mL, the AChE inhibitory activity and IC₅₀ (µg/mL) exhibited by the most potent extracts were: MIMSE (≈50%/111.9), TrCMSE (≈47%/201.2), DTMFE (≈32%/529.9), TTMSE (≈26%/495.4), and CLMSE (≈25%/438.4). The highest TPC were from MIMSE (156.2), TrCMSE (132.65), GAMLE (123.26), and CLMSE (119.63) in mg gallic acid equivalents/g, and for TFC were: MISME (87.35), GAMLE (73.26), ACMFE (69.54), CLMSE (68.35), and TCMSE2 (64.34) mg quercetin equivalents/gram. Conclusions: The results suggest that certain inedible and edible foodstuffs, most notably MIMSE, MPMSE, TrCMSE, GAMLE, and CLMSE may be beneficial to ameliorate the potentially damaging effects of redox stress.

Evaluation of the phytochemical content, in vitro antioxidant capacity, biochemical and histological effects of Dennettia tripetala fruits in healthy rats

We estimated the content of specific phytochemicals and in vitro antioxidant properties of the powder, aqueous, and ethanolic extracts of ripe Dennettia tripetala fruits. We also tested the biochemical and histological effects of these fruit extracts on healthy rats. Aqueous and ethanolic extracts were prepared from the powder of ripe D. tripetala fruits, and standard phytochemical methods were used to evaluate its phytochemical content and antioxidant properties. Eighteen rats were randomized into three groups, one of which served as control, while the second and third groups received the aqueous and ethanolic extracts of D. tripetala fruits, respectively, at a dose of 1,000 mg/kg bw daily for 28 days. Our results show that the powder as well as the aqueous and ethanolic extracts of ripe D. tripetala fruits contains phenols, flavonoids, saponins, tannins, and alkaloids. The plant powder as well as both extracts scavenged DPPH and hydrogen peroxide as well as reduced ferric ions. The extracts of D. tripetala fruits did not alter liver marker enzymes or serum protein profile of the rats. The extracts also did not alter the serum concentration of urea and creatinine and the antioxidant enzyme activity and lipid peroxidation levels in the liver but altered that of the kidney. The extracts altered the serum and liver lipid profile but not to any significant extents. Also, the extracts caused minimal congestion to the centrioles of the liver but were not in any other way toxic to the liver, kidney, or heart of the rats. Our results point to the fact that the fruits of D. tripetala possess phytochemicals with medicinal properties and are well tolerated by rats.

Essential Oils and Their Constituents Targeting the GABAergic System and Sodium Channels as Treatment of Neurological Diseases

Essential oils and the constituents in them exhibit different pharmacological activities, such as antinociceptive, anxiolytic-like, and anticonvulsant effects. They are widely applied as a complementary therapy for people with anxiety, insomnia, convulsion, pain, and cognitive deficit symptoms through inhalation, oral administration, and aromatherapy. Recent studies show that essential oils are emerging as a promising source for modulation of the GABAergic system and sodium ion channels. This review summarizes the recent findings regarding the pharmacological properties of essential oils and compounds from the oils and the mechanisms underlying their effects. Specifically, the review focuses on the essential oils and their constituents targeting the GABAergic system and sodium channels, and their antinociceptive, anxiolytic, and anticonvulsant properties. Some constituents target transient receptor potential (TRP) channels to exert analgesic effects. Some components could interact with multiple therapeutic target proteins, for example, inhibit the function of sodium channels and, at the same time, activate GABA_A receptors. The review concentrates on perspective compounds that could be better candidates for new drug development in the control of pain and anxiety syndromes.

Bactericidal and antioxidant properties of essential oils from the fruits Dennettia tripetala G. Baker

Background

The antibacterial and antioxidant properties of the essential oils (EOs) of unripe and ripe fruits of Dennettia tripetala and their potential for the management of infectious and oxidative-stress diseases were investigated in-vitro in this study.

Method

Essential oil obtained from the fruit in Clevenger modified apparatus, was characterized by high resolution GC-MS, while antioxidant and antibacterial properties were tested by spectrophotometric and agar diffusion methods respectively.

Results

The EO demonstrated strong antibacterial properties when subjected to multi –drug resistant bacterial strains: Enterococcus faecium (ATCC19434), Escherichia coli (ATCC 700728), Staphylococcus aureus (NCINB 50080), Listeria ivanovii (ATCC 19119), Enterobacter cloacae (ATCC13047) and four previously confirmed multi resistant bacterial isolates from our laboratory stock culture. The unripe fruit oil (UFO) demonstrated greater activity than the ripe fruit oil (RFO) against most of the tested bacteria with minimum inhibition concentrations (MIC) ranging between 0.05–0.20 mg/mL while that of the ripe fruit oil (RFO) ranged from 0.10–0.20 mg/mL. The IC₅₀ for RFO (0.62 ± 0.12 mg/mL) showed that it has higher antioxidant strength than UFO and vitamin C (0.87 ± 0.23 and 3.39 ± 0.12 mg/mL) but a lower activity compared to β-carotene (0.32 ± 0.22 mg/mL) in scavenging 2, 2-diphenyl-1-picrylhydrazyl radicals (DPPH^•). The EOs also demonstrated strong ability in scavenging three other different radicals (ABTS, lipid peroxide and nitric oxide radicals) in concentration dependant -manner.

Conclusion

Findings from this study suggest that apart from the local uses of the plant extracts, the EO has strong bioactive compounds, noteworthy antibacterial, antiradical properties and may be good candidates in the search for lead constituents for the synthesis of novel potent antibiotics.

A Review of the Uses and Medicinal Properties of Dennettia tripetala (Pepperfruit)

Dennettia tripetala (commonly known as Pepperfruit) is widely consumed by the inhabitants of West Africa due to its distinctive spicy taste. It is also used traditionally as a remedy for cough, fever, toothache, diabetes, and nausea. The highly nutritious fruit is rich in protein, carbohydrates, as well as the antioxidant vitamins A, C, and E. The plant possesses phytochemicals that have been shown to elicit antimicrobial, insecticidal, analgesic, and anti-inflammatory properties. The plant has also been shown to possess chemotherapeutic, antihyperglycemic, and antioxidant properties. In addition, D. tripetala finds application in food preservation and seasoning. This review is the first attempt to pool together scientific evidence for the ethnomedicinal uses of D. tripetala. A critique of the literature is provided, as well as suggestions for future studies that can pave the way for further discoveries on the medicinal effects of D. tripetala.

Anti-nociceptive activity of the crude extract of Myrianthus arboreus P. Beauv (Cecropiaceae) in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Myrianthus arboreus P. Beauv (Cecropiaceae) is a shrub or a tree plant widely distributed in Tropical Africa. In the South Eastern part of Nigeria, the leaves are used in traditional medicine as an analgesic for muscular pains, and also as an enema to relieve pain in the back and loins. Although no scientific study has been performed to validate its traditional use in pain management, this study therefore aims at investigating the anti-nociceptive activity of M. arboreus leaves extract in mice.

MATERIALS AND METHODS

Anti-nociceptive activity of M. arboreus was investigated using acetic acid induced writhing, formalin induced paw licks, hot plate, and tail flick tests. Acute toxicity was determined using a slightly modified Lorkes method.

RESULTS

The extract of M. arboreus produced a significant dose-dependent [F (4, 20)=13.48 p<0.001] inhibition of abdominal writhings induced by acetic acid. In the formalin paw licking test, it produced a significant dose-dependent inhibition of neurogenic and inflammatory pain [F (4, 17.5)=60.13 p<0.001]. It also produced a significant dose dependent [F (4, 20)=30.5 p<0.001; F (4, 20)=0.321 p<0.0001] prolongation of the latency and reaction time in the hot plate and tail immersion tests. Peak effect was observed at the highest dose (40 mg/kg). LD50 of the plant was found to be 894 mg/kg.

CONCLUSION

M. arboreus possesses potent antinociceptive activity mediated centrally and peripherally, an effect which may justify its traditional use in the management of pain.

Antinociceptive property of Olax subscorpioidea Oliv (Olacaceae) extract in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Olax subscorpioidea is a shrub or tree found in Nigeria, and other parts of Africa. It is used in the management of inflammatory disorder, mental illness, convulsion, pain, and cancer. However, there is dearth of information on scientific basis for its folkloric use in the management of pain. Therefore, the study was designed to investigate the antinociceptive property of the extract of Olax subscorpioidea (EOS) leaves in mice.

MATERIALS AND METHODS

Antinociceptive activity of EOS (12.5-50 mg/kg, i.p.) was investigated using acetic acid induced abdominal writhing, tail immersion, hot plate and formalin tests.

RESULTS

Extract of Olax subscorpioidea produced significant dose dependent inhibition of writhing frequency [F(4,20)=155.9, p<0.0001] and significant dose dependent inhibition of neurogenic and inflammatory pains [F(4,20)=116.7, p<0.0001; F(4,20)=40.05, p<0.0001]. It also produced a significant dose dependent prolongation of the latent period and reaction times in tail immersion and hot plate tests in mice [F(4,20)=19.49, p<0.0001; F(4,20)=97.95, p<0.0001].

CONCLUSION

Olax subscorpioidea possessed potent analgesic action, mediated centrally and peripherally, thus justifying its use in the management of pain.

Hypnotic, anticonvulsant and anxiolytic effects of 1-nitro-2-phenylethane isolated from the essential oil of Dennettia tripetala in mice

This study investigated the hypnotic, anti-convulsant and anxiolytic effects of 1-nitro-2-phenylethane (BPNE) obtained from the oil of Dennettia tripetala G. Baker (Annonaceae) and established its mechanism of action. The essential oil (EO) from the leaf, fruit and seed was obtained by hydrodistillation, followed by isolation of BPNE purified to 99.2% by accelerated gradient chromatography on silica, and identified by NMR and GC-MS. The pure BPNE and EO of the dried seed (93.6%) were comparatively evaluated for hypnotic, anticonvulsant and anxiolytic effects in mice. The acute toxicity of BPNE was determined and the LD50 was 490 mg/kg, intrapritonealy. The hypnotic activities of the EO and BPNE (50-400 mg/kg, i.p.) were assessed by loss of righting reflex, while sodium pentobarbitone (PBS) and diazepam (DZM) were used as positive controls. The anticonvulsant and anxiolytic effects of the EO and BPNE were evaluated in mice. Both BPNE and EO at doses ≥100 mg/kg induced spontaneous hypnosis with loss of righting reflex, significantly decreased sleep latency (SL) and also increased total sleeping time (TST) dose-dependently. They had comparable activity with NAP in TST. The BPNE exhibited higher hypnotic potency than EO at the same dose levels. The EO and BPNE offered comparable dose-related protections against PTZ- and strychnine-induced convulsions. Flumazenil (2 mg/kg) blocked the hypnotic and anticonvulsant (PTZ-convulsions) effects of both EO and BPNE. The essential oil at 5-20 mg/kg dose levels significantly (p<0.05) increased the percentage time spent and number of entries into the open arms. While at the same dose range BPNE significantly (p<0.05) increased the percentage time spent and the number of entries into the open arms respectively. The study concluded that 1-nitro-2-phenylethane exhibited dose dependent significant hypnotic, anticonvulsant and anxiolytic effects and it is the compound largely responsible for the neuropharmacological effects of the oil.

Studies on neuropharmacological profile of ethanol extract of Moringa oleifera leaves in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Moringa oleifera (family Moringaceae), commonly called Horseradish or tree of life, is traditionally used for the treatment of epilepsy and neurologic conditions.

AIM OF THE STUDY

The objective of this study is to investigate the neurobehavioural and anticonvulsant properties of the ethanol extract from the leaves of Moringa oleifera.

MATERIALS AND METHODS

Neurobehavioural properties were evaluated using the open field, hole board, Y-maze, elevated plus maze (EPM) and pentobarbitone-induced hypnosis. Pentylenetetrazole (leptazol), picrotoxin and strychnine induced convulsion tests were used to investigate the anti-convulsive actions of Moringa oleifera.

RESULTS

The result showed that the extract (250-2000mg/kg) caused a significant dose-dependent decrease in rearing, grooming, head dips and locomotion (P<0.001). It also enhanced learning and memory and increased anxiogenic effect. In addition, the extract (2000mg/kg) protected mice against pentylenetetrazol induced convulsion, but has no effect on picrotoxin and strychnine induced convulsion. The effects of the extract in the various models were comparable to those of the standard drugs used except in Y-maze, EPM and picrotoxin and strychnine induced convulsion. The LD50 obtained for the acute toxicity studied using oral route of administration was >6.4g/kg.

CONCLUSION

The findings from this study suggest that the ethanol extract of Moringa oleifera leaves possesses CNS depressant and anticonvulsant activities possibly mediated through the enhancement of central inhibitory mechanism involving release γ-amino butyric acid (GABA). The results partially justified the traditional use of the extract for the treatment of epilepsy.

Evaluation of an ethnomedicinal combination containing Semecarpus kurzii and Hernandia peltata used for the management of inflammation

CONTEXT

Scientific validation of an ethnomedicinal combination consisting of Semecarpus kurzii Engler (Anacardeaceae) leaves (SKL) and Hernandia peltata Meisn (Hernandeaceae) stem-bark (HPB), traditionally used in ailments related to inflammation, pain and fever.

OBJECTIVE

To validate in vivo and in vitro analgesic and antiinflammatory activities of methanol extract of SKL, HPB and their combination.

MATERIALS AND METHODS

Analgesic activity was tested by acetic acid induced writhing reflex and tail flick in Swiss albino mice, while the anti-inflammatory activity was studied in acute, subacute and chronic model on Wistar rats. The vascular permeability, membrane stabilization and protein denaturation were examined to know the possible mode of action.

RESULTS

Significant (p < 0.01) analgesic (78.04% inhibition of writhing) and antiinflammatory (72.54% inhibition of paw edema) activity was observed in combination of SKL and HPB extracts at 250 mg/kg each. The SKL extract alone inhibits acetic acid-induced vascular permeability (64.4%) at 500 mg/kg, while in combination at 250 mg/kg each, the inhibition was 69.49% (p < 0.01). Furthermore, SKL in combination with HPB (0.25 mg/mL each) prevent RBC hemolysis (61.91%) and inhibition of protein denaturation (76.52%)-like indomethacin.

DISCUSSION AND CONCLUSION

The SKL and HPB extract, alone (500 mg/kg) and in combination, (250 mg/kg each) had significant analgesic and antiinflammatory activity, probably by inhibiting the release of certain inflammatory mediators and membrane stabilization, due to the presence of triterpenes, tannins and related phytochemicals in the extracts. Thus, our results demonstrated that this combination provide the scientific rationale of its folk use.

Antioxidant and anti-inflammatory activities of essential oils: a short review

Essential oils are complex mixtures isolated from aromatic plants which may possess antioxidant and anti-inflammatory activities of interest in thye food and cosmetic industries as well as in the human health field. In this work, a review was done on the most recent publications concerning their antioxidant and anti-inflammatory activities. At the same time a survey of the methods generally used for the evaluation of antioxidant activity and some of the mechanisms involved in the anti-inflammatory activities of essential oils are also reported.

Evaluation of analgesic and anti-inflammatory activity of diospyros cordifolia extract

In this study we evaluated the analgesic and anti-inflammatory activities of the methanol extract of stem bark of Diospyros cordifolia (MEDC) Roxb. The analgesic effects of the stem bark of the plant was assessed in mice using the tail-flick method while carrageenan, histamine and dextran induced paw oedema was used to study the antiinflammatory effects in rats. The MEDC exhibited significant (p<0.01) analgesic effects comparable to the reference drug diclofenac sodium. MEDC also was evaluated for its anti-inflammatory potential against carrageenan, histamine and dextran induced rat paw edema. The methanol extract (25 and 50 mg / kg body weight) exhibited significant (p<0.01) activity against all phlogistic agents used in a dose dependent manner. All these effects were compared with reference drug phenylbutazone (100 mg/kg body weight).

Antinociceptive and anti-inflammatory activities of the ethanol extract of Annona muricata L. leaves in animal models

Antinociceptive and anti-inflammatory activities of the ethanol extract from Annona muricata L. leaves were investigated in animal models. The extract delivered per oral route (p.o.) reduced the number of abdominal contortions by 14.42% (at a dose of 200 mg/kg) and 41.41% (400 mg/kg). Doses of 200 and 400 mg/kg (p.o) inhibited both phases of the time paw licking: first phase (23.67% and 45.02%) and the second phase (30.09% and 50.02%), respectively. The extract (p.o.) increased the reaction time on a hot plate at doses of 200 (30.77% and 37.04%) and 400 mg/kg (82.61% and 96.30%) after 60 and 90 minutes of treatment, respectively. The paw edema was reduced by the ethanol extract (p.o.) at doses of 200 (23.16% and 29.33%) and 400 mg/kg (29.50% and 37.33%) after 3 to 4 h of application of carrageenan, respectively. Doses of 200 and 400 mg/kg (p.o.), administered 4 h before the carrageenan injection, reduced the exudate volume (29.25 and 45.74%) and leukocyte migration (18.19 and 27.95%) significantly. These results suggest that A. muricata can be an active source of substances with antinociceptive and anti-inflammatory activities.

Antinociceptive and antiinflammatory effects of essential oil of Dennettia tripetala G.Baker (Annonaceae) in rodents

In this study we evaluated the analgesic and anti-inflammatory activities of the essential oil (EO) of the fruits of Dennettia tripetala in rodents. The plant is a tropical African plant and the fruits are commonly eaten as spices and consumed as a stimulant, and its various parts are used in the treatment of fever, cough and as anti-emetics.The analgesic effects of the oil was assessed in mice using the hot plate, acetic acid-induced writhings and formalin test, while carrageenan-induced paw oedema was used to study the antiinflammatory effects in rats. The EO at 25-50 mg/kg exhibited significant (p<0.05) antinociceptive effects comparable to a potent opioid agonist, morphine (10 mg/kg) and non-steroidal anti-inflammatory drugs such as, aspirin (100 mg/kg) and indomethacin (80 mg/kg). The antinociceptive effect of the EO was also blocked by naloxone (2 mg/kg) in all the models used. The EO demonstrated significant (p<0.05) anti-inflammatory effect in the carrageenan-induced paw oedema model of inflammation that is also comparable to dexamethasone (1 mg/kg) The results showed that the essential oil of D. tripetala possesses significant antinociceptive and antiinflammatory effects in the animal models used. The results also suggest that the analgesic effects may be mediated both centrally as well as peripherally, while the antiinflammatory activity may be effective in both early and late phases of inflammation. The results obtained may therefore be used to rationalize the use of the plant in the treatment of pain and fever in traditional medicine.