Kratom (Mitragyna speciosa): User demographics, use patterns, and implications for the opioid epidemic

BACKGROUND

Kratom, a Southeast Asian plant with opioid-receptor mediated effects, has emerged as a potential substance of abuse, with limited data on its use and effects. This study characterized kratom user demographics, use patterns, and perceived drug effects.

METHODS

A cross-sectional, anonymous online survey was conducted between January and December 2017.

RESULTS

2,798 kratom users - mean age 40 (SD = 12); predominantly White (90 %), female (61 %), and located in the US (97 %) - completed the survey. Kratom was primarily taken orally in doses of 1-3 g (49 %), with daily use (59 %) being most common. Kratom was used for pain (91 %), anxiety (67 %), and depression (65 %), with high ratings of effectiveness. 1,144 (41 %) used kratom to stop or reduce prescription or illicit opioid use, citing decreased opioid withdrawal and craving related to kratom use, with 411 reporting >1-year continuous abstinence from opioids attributed to kratom use. Roughly one-third of respondents reported adverse effects of kratom, largely rated as mild in severity and lasting ≤24 h. Seventeen participants (0.6 %) sought treatment for adverse effects. Fifty-six individuals (2 %) met DSM-5 criteria for a past-year moderate or severe kratom-related substance use disorder (SUD). When asked how troubled they felt regarding their kratom use, the mean (SD) rating was 3.2 (9.8) on a scale from 0 to 100.

CONCLUSION

Kratom is used among White, middle-aged Americans for symptoms of pain, anxiety, depression, and opioid withdrawal. Although regular use was typical, kratom-related SUD and serious adverse effects were uncommon. Additional research on kratom epidemiology and pharmacology is imperative in light of the present opioid epidemic.

Analgesic activity of Gleditsia triacanthos methanolic fruit extract and its saponin-containing fraction

CONTEXT

Gleditsia triacanthos L. (Leguminosae) pods are used in folk medicine for pain relief as anodyne and narcotic.

OBJECTIVE

The objective of this study is to evaluate analgesic activity of Gleditsia triacanthos methanolic fruit extract (MEGT) and its saponin-containing fraction (SFGT).

MATERIALS AND METHODS

Peripheral analgesic activity was assessed using the acetic acid-induced writhing model in mice at doses of 140, 280, and 560 mg/kg and formalin test in rats at 100, 200, and 400 mg/kg doses. Central analgesic activity was evaluated using the hotplate method in rats (100, 200, and 400 mg/kg).

RESULTS

In the writhing test, six mice groups treated with MEGT and SFGT found ED50 values 268.2 and 161.2 mg/kg, respectively, displayed a significant decrease in writhing count compared with the group treated with standard drug indomethacin (14 mg/kg). SFGT (280 and 560 mg/kg) showed 64.94 and 70.78% protection, respectively, which are more than double % protection caused by indomethacin (31.82%). In the formalin test, MEGT and SFGT (ED50 values 287.6 and 283.4 mg/kg for phase I as well as 295.1 and 290.4 mg/kg for phase II, respectively) at 400 mg/kg showed significant % inhibition in both phase I (18.86 and 52.57%) and phase II (39.36 and 44.29%) with reference to 10 mg/kg indomethacin (56.0 and 32.29%). MEGT and SFGT caused significant delay in responses in hotplate model (ED50 values 155.4 and 200.6 mg/kg, respectively) compared with that of 10 mg/kg indomethacin at 30, 60, and 120 min.

DISCUSSION AND CONCLUSION

Central and peripheral analgesic activities induced by Gleditsia triacanthos fruits might account for its uses in folk medicine.

[Mechanism of catalytic ozonation for the degradation of paracetamol by activated carbon]

The degradation of paracetamol (APAP) in aqueous solution was studied with ozonation integrated with activated carbon (AC). The synergistic effect of ozonation/AC process was explored by comparing the degradation efficiency of APAP in three processes (ozonation alone, activated carbon alone and ozonation integrated with activated carbon). The operational parameters that affected the reaction rate were carefully optimized. Based on the intermediates detected, the possible pathway for catalytic degradation was discussed and the reaction mechanism was also investigated. The results showed that the TOC removal reached 55.11% at 60 min in the AC/O3 system, and was significantly better than the sum of ozonation alone (20.22%) and activated carbon alone (27.39%), showing the great synergistic effect. And the BOD5/COD ratio increased from 0.086 (before reaction) to 0.543 (after reaction), indicating that the biodegradability was also greatly improved. The effects of the initial concentration of APAP, pH value, ozone dosage and AC dosage on the variation of reaction rate were carefully discussed. The catalytic reaction mechanism was different at different pH values: the organic pollutions were removed by adsorption and direct ozone oxidation at acidic pH, and mainly by catalytic ozonation at alkaline pH.

Anti-inflammatory and analgesic effects of egg yolk: a comparison between organic and machine made

OBJECTIVES

Yolk composition may be influenced by the bird's dietary intake. Quality of egg yolk from different sources is also varied. Especially egg yolk from organic sources, those prepared by the hen and duck were naturally fed. Traditional medicine users in north of Iran believe the oil extracted by direct heat from egg yolk has analgesic activity. In this work anti-inflammatory and antinociceptive activities of organic and machine made hen yolk and duck yolk were evaluated.

MATERIALS AND METHODS

Three various sources of egg yolk (organic hens, duck and machine made) were chosen. Each yolk was extracted by two methods, solvent extraction (hexane) and direct heating. In order to investigate the analgesic and anti-inflammatory activity, carageenan, hot plate and writhing tests were carried out.

RESULTS

The organic hen and duck oil extracted by direct heat method showed the highest activity compared to other types. Organic sources may contain some special components which are not existed in machine made eggs. Oil samples obtained by direct heat from three different kinds of egg yolk showed significant anti-inflammatory activity at 100-300 mg/kg compared to controls (p < 0.001). All samples indicated analgesic properties at all doses in writhing test. The highest activity was seen at 300 mg/kg of organic hen egg yolk oil prepared by heat (HO) and hexane extract of duck egg yolk (ED) which was similar to 5 mg/kg morphine (p > 0.001). In hot plate test all of the oil samples did not show significant difference with controls. Hexane extract of organic egg yolk (EO) (300 mg/kg) and ED (200 and 300 mg/kg) showed significant analgesic activity in hot plate test.

CONCLUSIONS

This study confirms anti-inflammatory and analgesic scheme of yolk. We can also claim environmental and dietary condition is very important in yolk contents. In order to improve life quality of human beings and better efficiency for egg yolk components we suggest considering the way of feeding for poultry. We can propose organic yolk oil prepared by direct heat as an alternative remedy for inflammatory joint conditions.  

Oxidative removal of acetaminophen using zero valent aluminum-acid system: efficacy, influencing factors, and reaction mechanism

Commercial available zero valent aluminum under air-equilibrated acidic conditions (ZVA1/H+/air system) demonstrated an excellent capacity to remove aqueous organic compounds. Acetaminophen (ACTM), the active ingredient of the over-the-counter drug Tylenol, is widely present in the aquatic environment and therefore the treatment of ACTM-contaminated water calls for further research. Herein we investigated the oxidative removal of ACTM by ZVA1/H+/air system and the reaction mechanism. In acidic solutions (pH < 3.5), ZVA1 displayed an excellent capacity to remove ACTM. More than 99% of ACTM was eliminated within 16 hr in pH 1.5 reaction solutions initially containing 2.0 g/L aluminum and 2.0 mg/L ACTM at 25 +/- 1 degree C. Higher temperature and lower pH facilitated ACTM removal. The addition of different iron species Fe0, Fe2+ and Fe3+ into ZVA1/H+/air system dramatically accelerated the reaction likely due to the enhancing transformation of H2O2 to HO. via Fenton's reaction. Furthermore, the primary intermediate hydroquinone and the anions formate, acetate and nitrate, were identified and a possible reaction scheme was proposed. This work suggested that ZVA1/H+/air system may be potentially employed to treat ACTM-contaminated water.

Anti-inflammatory, analgesic and antipyretic activities of Linum usitatissimum L. (flaxseed/linseed) fixed oil

The fixed oil of L. usitatissimum (flaxseed/linseed) inhibited PGE2-, leukotriene-, histamine- and bradykinin-induced inflammation. The oil also inhibited arachidonic acid-induced inflammation, suggesting its capacity to inhibit both cyclooxygenase and lipoxygenase pathways of arachidonate metabolism. In tail immersion model, the oil raised the pain threshold to a lesser extent than morphine but showed excellent peripherally acting, analgesic activity comparable to aspirin, against acetic acid-induced writhing in mouse. In typhoid paratyphoid A/B vaccine-induced pyrexia, the oil showed antipyretic activity comparable to aspirin. The oil contains 57.38% alpha-linolenic acid. Dual inhibition of arachidonic acid metabolism, antihistaminic and antibradykinin activities of the oil could account for the biological activity and the active principle could be alpha-linolenic acid an omega-3 (18:3, n-3) fatty acid.

Ginger (Zingiber officinale Roscoe) elicits antinociceptive properties and potentiates morphine-induced analgesia in the rat radiant heat tail-flick test

Ginger (Zingiber officinale Roscoe), a well-known spice plant, has been used traditionally in the treatment of a wide variety of ailments. It has been shown that ginger is a calcium channel blocker; however, its influence on morphine analgesic effects has not been elucidated. We examined the effect of ginger root extract on nociceptive threshold and morphine-induced analgesia in male Wistar rats. To determine the effect of ginger on morphine analgesia, ginger extract (200, 400, and 600 mg/kg i.p.) was injected before a subeffective dose of morphine (2.5 mg/kg i.p.). The radiant heat tail-flick test was used to assess the nociceptive threshold before and at different times after drug administration. Our results showed that ginger extract elicited a significant antinociceptive effect. In addition, in groups that received both morphine and ginger, the observed analgesia was higher than that in groups treated with either morphine or ginger extract alone. Thus, the data indicate that ginger extract has a beneficial influence on morphine analgesia and can be an efficacious adjunct for pain management.

Anti-inflammatory, antinociceptive and antipyretic properties of the aqueous extract of Clematis brachiata leaf in male rats

Clematis brachiata Thunb. (Ranunculaceae) is used as a folk remedy for the treatment of pain, fever and inflammatory ailments. Aqueous extract of Clematis brachiata leaf was screened for its phytochemical constituents. The anti-inflammatory investigations were carried out using carrageenan and histamine-induced edema models; acetic acid writhing, formalin-induced pain and tail immersion models were used to evaluate antinociceptive activity while a Brewer's yeast-induced hyperthermia model was employed for the antipyretic experiment. Phytochemical screening of the extract revealed the presence of tannins, saponins, flavonoids and cardiac glycosides. The extract at 100, 200 and 400 mg/kg body weight significantly (P<0.05) reduced the edema paw volumes induced by carrageenan and histamine with the 400 mg/kg body weight extract being the most potent. On the antinociceptive front, while the extract reduced the writhing caused by acetic acid and the number of licks induced by formalin in a dose dependent manner, the increase in the reaction time by the extract in the tail immersion model was not dose-dependent. Again, there was significant (P<0.05) lowering of the Brewer's yeast-provoked elevated body temperature. The results suggest that the aqueous extract of Clematis brachiata leaves can be employed in the management of inflammation, pain and fever. These activities may be due in part to the flavonoid content of the extract.

Antipyretic, analgesic, anti-inflammatory and antioxidant activities of two major chromenes from Melicope lunu-ankenda

AIM OF THE STUDY

Melicope lunu-ankenda (Gaertn.) T.G. Hartley is used in Indian traditional medicine for fever, improving complexion and as a tonic. Previous studies have isolated fungicidal, antifeedant, anti-inflammatory and immunomodulatory compounds from Melicope lunu-ankenda. This study is aimed at the isolation and biological activity screening of potential molecules from the volatile oils and extracts of Melicope lunu-ankenda in the light of traditional applications.

MATERIALS AND METHODS

Volatile oil of Melicope lunu-ankenda leaves was isolated by hydrodistillation, characterized by GC-FID, GC-MS, LRI determination, Co-GC and database searches. Major chromene-type compounds in Melicope lunu-ankenda leaf oil, evodione and leptonol, were isolated by preparative TLC and characterized by UV-Vis, IR, 1H-, 13C-, 13C-DEPT NMR and EIMS. They were also isolated from the petroleum ether and acetone extracts of the leaves of Melicope lunu-ankenda by column chromatography in petroleum ether-ethyl acetate. Their contents in leaf oil, leaf and inflorescence extracts were estimated by HPTLC. Antipyretic (Baker's yeast-induced fever test), analgesic (acetic acid-induced writhing, tail immersion assays), anti-inflammatory (carrageenan-induced paw edema) and in vitro antioxidant (DPPH radical, superoxide radical scavenging) activities of evodione and leptonol were tested.

RESULTS AND CONCLUSIONS

Gas chromatographic analyses found 50.7% monoterpene hydrocarbons, 0.4% oxygenated monoterpenes, 3.2% sesquiterpene hydrocarbons, 0.7% oxygenated sesquiterpenes and 43.7% chromene-type compounds in Melicope lunu-ankenda leaf oil, with evodione (20.2%) and leptonol (22.5%) as its two major constituents. HPTLC estimations in the petroleum ether, acetone extracts (leaf, inflorescence) and leaf oil found evodione 1.0% (dr. wt., leaf), 1.1% (inflorescence), 0.04% (fr. wt. leaves, leaf oil), and leptonol 0.3% (leaf), 0.3% (inflorescence) and 0.04% (leaf oil). Leptonol (200 mg/kg) showed good antipyretic activity. DPPH radical scavenging assay found moderate activity for leptonol (68.7%, 500 microM), whereas evodione showed near-zero activity. A very similar trend was found in superoxide radical scavenging activity of leptonol (64.5%) and evodione (10.3%), both at 100 microg/ml. Evodione and leptonol showed moderate analgesic activities in acetic acid-induced writhing and tail immersion assays. Moderate anti-inflammatory activity was found for both evodione (59.4%) and leptonol (49.0%) at 100 mg/kg.

ETHNOPHARMACOLOGICAL RELEVANCE

Biological activities of evodione and leptonol isolated from Melicope lunu-ankenda justify its traditional uses as a remedy for fever, inflammation and as a tonic.

Analgesic activity of Heliopsis longipes and its effect on the nervous system

Heliopsis longipes S.F. Blake (Asteraceae: Heliantheae) (chilcuague) is used in Mexican traditional medicine against parasites and to alleviate tooth and muscle pains. Its biocide effect has already been experimentally demonstrated; however, its analgesic action and its action on the nervous system (NS) have not been investigated yet. The objectives of this study were to evaluate the analgesic action of affinin and the H. longipes root ethanol extract, as well as their effects on the NS using an animal model. The ethanol extract was obtained by maceration, and affinin was purified from it through chromatographic techniques. Chemical and thermal analgesia were used to assess their analgesic proprieties. Irwin's test was used to evaluate their stimulating or depressing effects. The ethanol extract and affinin displayed analgesic action similar to ketorolac and stimulating effect comparable to caffeine on the nervous system of adult mice.

Phenacetin isolated from Bursera grandifolia, a herbal remedy with antipyretic properties

Bursera grandifolia and other related species have been used in traditional herbal medicine in Mexico and other Latin American countries for their analgesic, antipyretic and anti-inflammatory properties. From the chloroform extract of leaves of B. grandifolia, a substance was isolated and identified as phenacetin, a well known compound with widely tested analgesic and antipyretic properties. The structural identity of the compound was elucidated on the basis of chemical and spectroscopic evidence and by comparison with an authentic sample.

Acute toxicity study and antipyretic effect of the brown alga Turbinaria conoides (J. Agardh) Kuetz

The active principles of brown alga, Turbinaria conoides (J.Agardh) Kuetz. (Sargassaceae) was extracted with n-hexane, cyclohexane, methanol and ethanol-water (1:1) and investigated for acute toxicity and antipyretic activity. Phytochemical analysis of the extracts revealed the presence of steroids, flavonoids and reducing sugars. Acute toxicity study was performed in Wistar rats after administration of extracts orally. No mortality was observed up to the dose of 5 g/kg for methanol and ethanol-water (1:1) extracts whereas n-hexane and cyclohexane extracts were found to be toxic at the dose levels of 1 g/kg and 2 g/kg respectively. In biochemical analysis, n-hexane, cyclohexane and ethanol-water (1:1) extracts caused a significant (P<0.01) increase in serum cholesterol, protein and alkaline phosphatase levels. In haematological studies, a significant difference was observed for cyclohexane and ethanol-water (1:1) extracts in polymorphs, lymphocytes and eosinophils when compared to the control. Antipyretic activity of extracts (100-400 mg/kg doses) was carried out on yeast-induced pyrexia in rats. Cyclohexane extract exhibited more significant antipyretic activity (P<0.01) than the other extracts at a dose of 200 mg/kg (54.43%), which was comparable to that of paracetamol at a dose of 33 mg/kg. The findings validated the use of this brown alga in traditional cure of children's fever.

Evaluation of the anti-pyretic potential of Orthosiphon stamineus Benth standardized extract

The anti-pyretic activity of a standardized methanol/water (50/50) extract of Orthosiphon stamineus Benth. (SEOS) was investigated for its effect on normal body temperature and yeast-induced pyrexia in Sprague Dawley (SD) rats. The SEOS showed no effect on normal body temperature. Doses of 500 and 1000 mg/kg body weight of SEOS significantly reduced the yeast-induced elevation in body temperature. This effect persisted up to 4 h following the administration of the extract. The anti-pyretic effect of SEOS was comparable with that of paracetamol (acetaminophen in U.S) (150 mg/kg p.o.), a standard anti-pyretic agent. HPLC study revealed that rosmarinic acid, sinensetin, eupatorin and tetramethoxyflavone were present in SEOS in the amounts of 7.58%, 0.2%, 0.34% and 0.24% respectively. The LD(50) of the extract in rats was higher than 5000 mg/kg body weight. Therefore, the present study ascertained that SEOS possesses a significant anti-pyretic activity.

Anti-inflammatory and anti-pyretic activities of earthworm extract-Lampito mauritii (Kinberg)

AIM OF THE STUDY

Experiments were conducted to understand the therapeutic properties such as anti-inflammatory and anti-pyretic activities of biologically active extract isolated from whole earthworm (Lampito mauritii, Kinberg).

MATERIALS AND METHODS

Inflammation in the hind paw of Wistar albino rat, Rattus norvegicus, was induced by histamine, granuloma pouch was induced by turpentine and pyrexia induced by Brewer's yeast in rats were followed as earlier studies. Anti-inflammatory drug-indomethacin and anti-pyretic drug-paracetamol were used as standard drug for comparison.

RESULTS

Administration of indomethacin (10mg/kg), paracetamol (150 mg/kg) and/or different doses of earthworm extract (EE) (50, 100 and 200mg/kg) reduced and restored to normal conditions in a dose-dependent manner of histamine and turpentine induced inflammation, and Brewer's yeast induced pyretic in rats.

CONCLUSIONS

The most significant inhibition of paw oedema and granuloma and also the significant reduction in hyperpyrexia in rats when treated with standard drugs as well as different doses of EE, reflect the presence of anti-inflammatory and anti-pyretic properties of EE similar to glycoprotein complex (G-90).

Anti-inflammatory and analgesic alkaloid from Sida cordifolia linn

The analgesic and anti-inflammatory activities of a new alkaloid, 1,2,3,9-tetrahydro-pyrrolo [2,1-b] quinazolin-3-ylamine (compound 1) isolated from Sida cordifolia Linn. were investigated in animal models. In the acetic acid induced writhing model, the compound 1 showed 25.4 (P<0.05) and 52.43% (P<0.01) inhibition of writhing response at doses of 25 and 50 mg/kg body weight respectively. The alkaloid also produced significant increase in the tail flick latency in radiant heat tail-flick method. In Carrageenan induced rat paw edema the compound 1 produced 16.93 and 24.43 % inhibition of paw edema at the doses of 25 and 50 mg/kg body weight respectively at the third hour of study.

Separation and determination of four active components in medicinal preparations by flow injection-capillary electrophoresis

A simple, rapid and accurate method for the separation and determination of paracetamol (Par), pseudoephedrine hydrochloride (Pse), dextromethorphan hydrobromide (Dex) and chlorphenamine hydrogen maleate (Chl) was developed by combination of flow injection and capillary zone electrophoresis for the first time. The analysis was carried out using an unmodified fused-silica capillary (75 mm x 75 microm i.d. x 375 microm o.d., effective separation length of 45 mm) and direct ultraviolet detection at 214 nm, 1.0 kV applied voltage. The optimized running buffer composed of 75 mM sodium borate-15% (v/v) acetonitrile (ACN) (pH* 9.30) was applied for the separation of the four analytes. The separation was achieved in 4.5 min. The sample throughput rate could reach up to 19 h(-1). The repeatability (defined as relative standard deviation) was 0.6%, 1.0%, 2.1%, 1.9% with peak height evaluation and 0.7%, 1.8%, 0.7%, 1.1% with peak area evaluation for Par, Pse, Dex and Chl, respectively. The limits of detection (S/N=3) were 0.22 microg/ml, 0.29 microg/ml, 0.42 microg/ml and 0.70 microg/ml for Par, Pse, Dex and Chl, respectively. The method was successfully applied to determine the four compounds in three cold medicines with recoveries in the range of 97.18-105.15%.

Phytochemical and Analgesic Activity of Extract, Fractions and a 19-Hydroxyursane-Type Triterpenoid Obtained from Rubus rosaefolius (Rosaceae)

The Rubus species has been used in folk medicine to treat several ailments, including infectious and dolorous diseases. In this work we evaluate the phytochemical and analgesic activity of hydroalcoholic extract (HE), some fractions (hexane, dichloromethane, ethyl acetate and butanolic), as well as a pure compound denoted as 28-methoxytormentic acid (1) obtained from aerial parts of R. rosaefolius. The compounds were isolated and identified by chromatographic and spectroscopic analysis. The antinociceptive action was evaluated by two well know models of pain in mice: writhing and formalin induced-pain. The results showed that the HE, fractions and compound (1), exhibits potent and dose-related analgesic activity when evaluated in both models of pain. Compound (1), which seems to be the main active principle, showed promising analgesic effects, being several times more potent than aspirin and paracetamol, two well-known analgesic and antiinflammatory drugs used as reference. In the writhing test, it showed an ID(50) of 5.10 (3.64-7.14) mg kg(-1) and maximum inhibition (MI) of 64.22%. When analyzed by formalin induced-pain test, this compound showed ID(50) values of 9.98 (8.08-12.31) and 6.31 (5.07-7.98) mg kg(-1) and MI of 59.37 and 90.37% for the first and second phases, respectively. The results justify, at least partially the popular use of this plant for the treatment of dolorous processes, suggesting that 1 is one of the active principles of this plant.

Anti-inflammatory, anti-nociceptive and antipyretic effects of extracts of Phrygilanthus acutifolius flowers

This study was intended to evaluate the anti-inflammatory, antipyretic and analgesic activities of aqueous and ethanol extracts of Phrygilanthus acutifolius flowers in several experimental standard models in rats, following oral administration. The results showed that the aqueous extract significantly reduced the oedema induced by carrageenan within 1-5 h post-dosing at all dose levels used. On the analgesia property, acetic acid-induced writhing was significantly reduced. In the formalin test, the extract also significantly decreased the painful stimulus in both phases of the test. The tail immersion confirms central acting analgesic property of the extracts. Overall, the analgesic tests conducted revealed that the extract had central and peripheral properties. Its effects on pyresis were also appreciable. It significantly reduced fever at doses greater than 200 mg/kg within 2 h on yeast-induced hyperthermia in rats.

Effect of Salvia miltiorrhiza injection on hyperpolarization-activated current channels in dorsal root ganglion neurons of rats

AIM

To explore the modulation of Salvia miltiorrhiza on hyperpolarization-activated current (Ih) channels in dorsal root ganglion (DRG) neurons of rats and identify the mechanism of Salvia miltiorrhiza in alleviating pain and inhibiting calcium overload. Methods The effect of Salvia miltiorrhiza injection on Ih channels in DRG neurons of rats were examined by using whole-cell patch clamp technique. Results The experimental results showed that the amplitude of Ih evoked by -150 mV was (-1.06 +/- 0.18) nA. The Ih could be fitted well into the single kinetics and the time constant of activation, pi was clearly voltage-dependent with tau = (322.14 +/- 28.81) ms at -100 mV, decreasing to tau = (62.51 +/- 9.78) ms at -150 mV. The reversal potential of Ih was (-35.03 +/- 1.12) mV measured from tail currents. But no significant differences were found between the DRG neurons in the absence and presence of Salvia miltiorrhiza injection (10%, 25%, 50%) in the current amplitude, the time constant of activation and the reversal potential. The only difference between the DRG neurons in the absence and presence of Salvia miltiorrhiza injection was the half-activation potential of Ih. In control recordings the half-activation potential was (-106.07 +/- 3.59) mV. By comparison, the half-activation potentials changed to (-111.59 +/- 3.79) mV (n=31 neurons, P < 0.05), (-119.37 +/- 4.96) mV (n=31 neurons, P < 0.05) and (-121.23 +/- 3.86) mV (n=31 neurons, P < 0.05) in the presence of 10%, 25%, 50% Salvia miltiorrhiza injection, respectively.

CONCLUSION

Only the half-activation potential of Ih in the arthritic and neuropathic rat models shifted in the depolarizing direction, which increased the electrophysiological activity of Ih and made it related to peripheral hyperalgesia. The selective inhibition of Salvia miltiorrhiza on the electrophysiological activity of Ih may be one of the mechanisms underlying its analgesic effects.

2-Methoxycinnamaldehyde Reduces IL-1.BETA.-Induced Prostaglandin Production in Rat Cerebral Endothelial Cells

Prostaglandin E2 (PGE2) works as a common final mediator of the febrile. Guizhi-Tang, one of the most famous traditional Chinese medical formula used to treat influenza, common cold and other pyretic conditions, was previously reported to reduce the production of PGE 2 in rats. 2-Methoxycinnamaldehyde is a principle compound isolated from Guizhi-Tang. The aim of the present study was to investigate the effects of 2-methoxycinnamaldehyde on PGE2 production of rat cerebral endothelial cells (CECs). 2-Methoxycinnamaldehyde dose-dependently inhibited interleukin (IL)-1beta-induced PGE2 production in CECs with IC50 values of 174 microM. IL-1beta stimulation increased the protein, activity and mRNA expression of cyclooxygenase (COX)-2 but not COX-1. 2-Methoxycinnamaldehyde reduced IL-1beta-induced protein and activity of COX-2, but did not influence the COX-2 mRNA expression. Our results show that prostaglandin production in CECs during stimulated conditions is sensitive to inhibition by 2-methoxycinnamaldehyde and suggest that 2-methoxycinnamaldehyde may reduce COX-2 protein level and activity but not COX-2 mRNA.

Antipyretic activity of Alstonia macrophylla Wall ex A. DC: an ethnomedicine of Andaman Islands

PURPOSE

Alstonia macrophylla Wall ex A. DC. Leaf, used in different ailments by the Onge tribes of Little Andaman Island, India, was investigated for its antipyretic potential.

METHODS

The methanol extract and its fractions were tested on normal body temperature and yeast-induced pyrexia in Wistar Albino rats.

RESULTS

The leaf extract at oral doses of 200 and 300 mg/kg, and the n-butanol fractions of the extract at 50 mg/kg showed significant reduction in normal body temperature and yeast-provoked elevated temperature in a dose-dependent manner comparable to that of standard antipyretic drug paracetamol. The antipyretic effect was started at 1 h and extended for at least 5 h after the drug administration.

CONCLUSIONS

The antipyretic effect was more pronounced when the fraction A and B was administered together, indicating that both the fractions may contain antipyretic compounds which produce an additive effect in combination. Phytochemically these fractions contain beta-sitosterol and ursolic acid.

Anti-inflammatory, analgesic and antipyretic effects of methanol extract from Bauhinia racemosa stem bark in animal models

In this study, the anti-inflammatory, analgesic, and antipyretic effects of 50, 100 and 200 mg/kg body weight of methanol extract obtained from Bauhinia racemosa stem bark, the so-called MEBR, were investigated. The effects of MEBR on the acute and chronic phases of inflammation were studied in carrageenan, dextran and mediators (histamine and serotonin)-induced paw oedema and cotton pellet-induced granuloma, respectively. Analgesic effect of MEBR was evaluated in acetic acid-induced writhing and hotplate tests. Antipyretic activity of MEBR was evaluated by yeast-induced hyperpyrexia in rats. The anti-oedema effect of MEBR was compared with 10 mg/kg of indomethacin orally. In acute phase of inflammation, a maximum inhibition of 44.9, 43.2, 44.8 and 45.9% (P<0.001) was noted at the dose of 200 mg/kg b.w. after 3h of treatment with MEBR in carrageenan, dextran, histamine and serotonin-induced paw oedema, respectively. Administration of MEBR (200 mg/kg b.w.) and indomethacin (10 mg/kg b.w.) significantly (P<0.05) decreased the formation of granuloma tissue induced by cotton pellet method at a rate of 50.4 and 56.2%, respectively. The extract also inhibited peritoneal leukocyte migration in mice. The MEBR also produced significant (P<0.01) analgesic activity in both models. Further, the MEBR potentiated the morphine- and aspirin-induced analgesic in mice. Treatment with MEBR showed a significant (P<0.01) dose-dependent reduction in pyrexia in rats. The results suggest that MEBR possess potent anti-inflammatory, analgesic and antipyretic activity.

Anti-inflammatory, anti-nociceptive and antioxidant activities of Balanites aegyptiaca (L.) Delile

The anti-inflammatory and anti-nociceptive activities of methanol (ME), butanol (BE) extracts and of two new saponins isolated from Balanites aegyptiaca bark were evaluated. The study was carried out in vivo and in vitro. The samples, extracts and pure substances, were intra-gastrically administered to animals. Two different animal models, the carrageenin-induced edema, in the rat, and acetic acid-induced writhing test in mice, were adopted. Moreover, the antioxidant power of extracts, fractions and individual constituents from Balanites aegyptiaca has been evaluated in vitro, using a method based on the Briggs-Rauscher (BR) oscillating reaction. Results obtained demonstrate that both ME or BE have a significant effect at the highest dose on the number of abdominal writhes induced by acetic acid, with a 38 and 54% inhibition respectively, but no significant difference was observed for extracts at the lowest dose and for the pure compounds compared with control animals. The same extracts exhibit a significant reduction on the rat paw edema. The inhibition produced by ME is about the same (28+/-3% lowest dose, 32+/-3% highest dose) after administration. A more evident effect is obtained by BE (41+/-3% and 68+/-6% respectively) and single saponins B1 and B2 (62+/-5% and 59+/-6% respectively) after oral administration. The antioxidant activity obtained seems to be in good accordance with the pharmacological results. The histological sections of rat paw confirm the antiflogistic activity of the plant extracts.

Antinociceptive and anti-inflammatory activities of Acacia pennata wild (Mimosaceae)

The butanolic fraction of dried leaves of Acacia pennata (Mimosaceae) was tested for analgesic and anti-inflammatory activities in animal models. It showed significant protective effects against chemical stimuli (acetic acid and formalin) in the mouse. It also produced a significant increase of the threshold of sensitivity to pressure-induced pain in the rats. The extract revealed an inhibitory effect in carrageenin-induced rat paw oedema in the late phase. The results suggested that a peripheral mechanism is involved in the analgesic, associated to anti-inflammatory effect (NSAIDs-like). Among the class of compounds characterized in this fraction, flavonoids may be mainly responsible for the pharmacological activities.

Antiallergic, Antipyretic, Hypoglycemic and Hepatoprotective Effects of Aqueous Extract of Coronopus didymus LINN

The aqueous extract of whole plant of Coronopus didymus LINN (CD) [Family: Bracicacea] was screened for antiallergic, antipyretic and hepatoprotective effects in rats and hypoglycemic activity in mice. The extract showed significant antiallergic, antipyretic, hypoglycemic and hepatoprotective activity at 200 and 400 mg/kg doses on oral administration. Mechanistically, CD acts as an antioxidant as evidenced by its ability to scavenge DPPH and superoxide radicals. All the observed activities may be due to the presence of flavonoids, saponins and tannins as they are reported to possess a variety of biological activities.

Antiinflammatory, lack of central analgesia and antipyretic properties of Acanthus montanus (Ness) T. Anderson

Aqueous leaves extract of Acanthus montanus (Nees) T. Anderson (Acanthaceae) were tested for antiinflammatory, analgesic and antipyretic properties. This was done using standard methodologies following oral administration of the extract. The results showed that the extract significantly reduced the oedema induced by carrageenan within 30 min with 200 mg/kg being the most potent. On the analgesia front, acetic acid writhing test was significant. The extract reduced only the number of paw licks of phase 2 and not phase 1 of formalin test. The results on hotplate and tail immersion tests excluded central acting analgesic properties of the extract. In overall, the analgesic tests conducted revealed that the extract had only peripheral analgesic properties. Its effect on pyresis was also observed to be appreciable. It significantly reduced fever at doses greater than 100 mg/kg within 6 h.

Evaluation of anti-pyretic and analgesic activity of Emblica officinalis Gaertn

The present study was designed to investigate the anti-pyretic and analgesic activity of ethanol (EEO) and aqueous (AEO) extracts of Emblica officinalis fruits in several experimental models. A single oral dose of EEO and AEO (500 mg/kg, i.p.) showed significant reduction in brewer's yeast induced hyperthermia in rats. EEO and AEO also elicited pronounced inhibitory effect on acetic acid-induced writhing response in mice in the analgesic test. Both, EEO and AEO did not show any significant analgesic activity in the tail-immersion test. These findings suggest that extracts of Emblica officinalis fruits possessed potent anti-pyretic and analgesic activity. Preliminary phytochemical screening of the extracts showed the presence of alkaloids, tannins, phenolic compounds, carbohydrates and amino acids, which may be responsible for anti-pyretic and analgesic activities.

Anti-inflammatory and anti-hyperalgesic effects of sesquiterpene lactones from Magnolia and Bear's foot

Sesquiterpene lactones possess a variety of biological activities, including anti-inflammatory activity. Two plants native to the southeastern United States, Magnolia grandiflora (L.) and Smallanthus uvedalius (L.) [syn Polymnia uvedalius (L.)], are novel sources of the sesquiterpene lactones parthenolide and enhydrin, respectively. In this study, the anti-inflammatory and anti-hyperalgesic effects of these isolated lactones from these two plant sources were evaluated in the rat carrageenan inflammation model. Rats received ip injections of either vehicle (propylene glycol), indomethacin (5 mg/kg), 11,13-dihydroparthenolide (20 mg/kg), parthenolide (5 or 20 mg/kg) or enhydrin (5 or 20 mg/kg). A 100-microl injection of 2.0% carrageenan was made into the plantar surface of the right hindpaw. Paw withdrawal latencies and paw volumes in both inflamed and non-inflamed paws were recorded at four test intervals: pre-inflammation baseline (0 time point), and 1, 2 and 4 h post-carrageenan injection. Vehicle-treated animals exhibited a significant time-dependent hyperalgesic and edema response that was greatest at the 4-h test interval. Indomethacin significantly blocked the hyperalgesic response and modestly attenuated the edema response. Parthenolide (20 mg/kg) and enhydrin (20 mg/kg) significantly blocked the hyperalgesic response and significantly attenuated the edema response; 11,13-dihydroparthenolide did not affect either inflammation or hyperalgesia. These findings suggest that parthenolide and enhydrin from these plant sources may be useful in the treatment of inflammatory pain.

Bulgarian propolis induces analgesic and anti-inflammatory effects in mice and inhibits in vitro contraction of airway smooth muscle

Propolis is a bee product, which has long been used in folk medicine for the management of different diseases. In this study we evaluated the analgesic and anti-inflammatory effects of a standard ethanolic extract of Bulgarian propolis (Et-Blg) in mice and its in vitro effect on airway smooth muscle. Et-Blg inhibited acetic acid-induced abdominal contortions with an ID(50) = 7.4 +/- 0.7 mg. kg(-1). In the formalin test, the extract caused a significant reduction in pain in mice treated with 100 mg. kg(-1) Et-Blg during the neurogenic phase and for the inflammatory phase with all doses of the extract, with an ID(50) = 2.5 +/- 0.4 mg. kg(-1). Et-Blg inhibited also the capsaicin-induced ear edema in mice; however, this extract was ineffective when assessed in the tail-flick and hot-plate thermal assays. The analgesic effect of Et-Blg was associated with the inhibition of inflammatory responses and not to a simple irritation of nervous terminals. In vitro, this extract inhibited the contraction of trachea smooth muscle induced by histamine (IC(50) = 50 +/- 5 microg. mL(-1)), capsaicin (IC(50) = 26.8 +/- 3 microg. mL(-1)), 80 mM KCl (IC(50) = 27.8 +/- 3 microg. mL(-1)), and carbachol (IC(50) = 54 +/- 2 microg. mL(-1)).

Purification and characterization of a new peptide with analgesic effect from the scorpion Buthus martensi Karch

Anew peptide, designated as Buthus martensi Karch (BmK) AngM1, with an isoelectric point (pI) of 5.8 was purified and characterized from the venom of Buthus martensi Karch. The molecular mass was calculated as 7040.5 Da from multiple-charged ions by elelctrospray ionization mass spectroscopy (ESI/MS). The complete amino acid sequence of BmK AngM1 of 64 amino acid residues was determined by automatic sequencing of N-terminal part of the native peptide and the fragments of reduced and S-carboxymethylated (RCM)-peptide degraded by Staphylococcus aureaus V(8) protease and TPCK(N-p-Tosyl-L-phenylalanine chloromethyl ketone)-treated trypsin. Bioactivity tested using mouse-twisting model showed an evident analgesic effect with 63.0% (P < 0.001) inhibition efficiency at the dose of 0.8 mg/kg, but the LD(50) was larger than 50 mg/kg. Electrophysiological studies showed that BmK AngM1 at the concentration of 1 microm obviously inhibit voltage-dependent Na(+) current (I(Na)) and voltage-dependent delayed rectifier K(+) current (I(K)) but had no effects on transient K(+) current.

Studies on the anti-inflammatory and analgesic properties of Tithonia diversifolia leaf extract

A methanol extract of the dried leaves of Tithonia diversifolia was investigated for anti-inflammatory and analgesic activities. The extract (50-200 mg/kg, p.o.) produced dose-related inhibition of carrageenan-induced paw oedema and cotton pellet-induced granuloma in rats. At the same doses, analgesic effect was also observed with hot plate latency assays maintained at (55 degrees C) as well as on the early and late phases of formalin-induced paw licking in rats. The results of the present study further confirm the use of Tithonia diversifolia traditionally for the treatment of painful inflammatory conditions.

Antioxidant, antimicrobial, antiulcer and analgesic activities of nettle (Urtica dioica L.)

In this study, water extract of nettle (Urtica dioica L.) (WEN) was studied for antioxidant, antimicrobial, antiulcer and analgesic properties. The antioxidant properties of WEN were evaluated using different antioxidant tests, including reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activities. WEN had powerful antioxidant activity. The 50, 100 and 250 microg amounts of WEN showed 39, 66 and 98% inhibition on peroxidation of linoleic acid emulsion, respectively, while 60 microg/ml of alpha-tocopherol, exhibited only 30% inhibition. Moreover, WEN had effective reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activities at the same concentrations. Those various antioxidant activities were compared to standard antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), quercetin, and alpha-tocopherol. In addition, total phenolic compounds in the WEN were determined as pyrocatechol equivalent. WEN also showed antimicrobial activity against nine microorganisms, antiulcer activity against ethanol-induced ulcerogenesis and analgesic effect on acetic acid-induced stretching.

[Effect of guizhi tang and its active components on the fever induced by EP3 agonist]

OBJECTIVE

To investigate the effect of Guizhi Tang and its active components on the fever induced by EP3 receptor agonist sulprostone in rats.

METHOD

The rise in body temperature evoked by a LCV(lateral cerebroventricle)-injection of sulprostone was compared with that of sulprostone induced-fever rats pretreated with Guizgi Tang and its active compounds, cinnamaldehyde, cinnamic acid and total glucosides of paeony.

RESULT

Pretreatments with Guizhi Tang and cinnamaldehyde inhibited the rise in body temperature induced by sulprostone, while cinnamic acid tended to augment the fever. The sulprostone-induced fever was blocked by an ip pretreatment of total glucosides of paeony even below the basement.

CONCLUSION

Present data suggest that interruption with the down-stream events of EP3 receptor may contribute to the antipyretic action of Guizhi Tang, cinnamaldehyde and the total glucosides of paeony, while cinnamic acid may have no such effect.

Analgesic, antipyretic, anti-inflammatory effects of methanol, chloroform and ether extracts of Vernonia cinerea less leaf

The chloroform, methanolic and ether extracts of Vernonia cinerea (Asteraceae; Less) leaf (100, 200 and 400mg/kg intraperitoneally) were tested in: acetic acid-induced writhing in mice, carrageenin-induced oedema and brewer's yeast-induced pyrexia in rats to assess their analgesic, anti-inflammatory, antipyretic and behavioral activities, respectively. The changes in writhings and behavioural activities in mice, the pyrexia and paw volumes in rats were reduced significantly (P<0.05) compared to the control. There was an increase in pain threshold on the oedematous right hind limb paw of the rats. These results indicate that the extracts could possess analgesic, antipyretic and anti-inflammatory properties. All these effects and the changes in the behavioural activities could be suggested as contributory effects to the use of V. cinerea leaf in the treatment of malaria.

[Comparative study on pharmacodynamic effects of yinqiao powder decoction and its granule]

OBJECTIVE

To compare the pharmacodynamic effects of Yinqiao Powder on dividual decoction, admixture decoction and granule.

METHODS

The mouse and rat inflammatory models were established by dimethylbenzene and carrageenin respectively. The rabbit model was established by typhoid Vi polysaccharide bacterin through ear vein and serolysin was induced by chick red cell. The effects of different dosage forms on inflammation antipyresis and inhibiting serolysin were observed.

RESULTS

All three dosage forms of Yinqiao Powder could inhibit mouse auricle swelling and rat toe swelling, possessed the antithemic action and could accelerate the formation of serolysin(p < 0.01). But there were no difference among these three dosage forms in pharmacodynamic effects.

CONCLUSIONS

Three dosage forms of Yinqiao Powder had the similar effects in above-mentioned pharmacodynamic markers.

Berberis crataegina DC. root exhibits potent anti-inflammatory, analgesic and febrifuge effects in mice and rats

Extracts obtained from the roots and barks of various Berberis species are used as folk remedy worldwide for the treatment of various inflammatory ailments including lumbago, rheumatism and to reduce fever. Effects of the extracts and fractions from the roots of Berberis crataegina DC. (Berberidaceae) were studied using various in vivo models of inflammation in mice and rats and observed potent inhibitory activity against carrageenan- and serotonin-induced hind paw oedema, acetic acid-induced increased vascular permeability, castor oil-induced diarrhoea, and Freund's complete adjuvant-induced (FCA) arthritis models. Through bioassay-guided fractionation berberine was isolated as the main active ingredient. Moreover, a dose-dependent analgesic activity was determined, which assessed by using the model based on the inhibition of acetic acid-induced writhing reflexes, as well as antipyretic activity on FCA-induced increased body temperature. Acute and subchronic toxicity studies were also performed.

Active constituents isolated from Psoralea glandulosa L. with antiinflammatory and antipyretic activities

The antiinflammatory and antipyretic activities of the petroleum ether extract (PEE), dichloromethane extract (DME) and methanol extract (ME1) of the aerial part of Psoralea glandulosa L. (Papilionaceae) were studied. The bioactivity-guided fractionation of the active extracts yielded the isolation of bakuchiol (Bk) from the petroleum ether as the active compound, cyclobakuchiols A and B (Cbk), and angelicin (Ang) from DME.

Analgesic components of saposhnikovia root (Saposhnikovia divaricata)

By activity-oriented separation using the writhing method in mice, the analgesic components of Saposhnikovia root (Saposhnikovia divaricata Schischkin; Umbelliferae) were identified to be chromones, coumarins, polyacetylenes and 1-acylglycerols. Two new components, divaricatol and (3'S)-hydroxydeltoin, were also isolated. The most potent analgesia was observed in chromones such as divaricatol, ledebouriellol and hamaudol, which inhibited writhing inhibition at an oral dose of 1 mg/kg in mice. Acylglycerols also showed inhibition significantly at a dose of 5 mg/kg. In some pharmacological tests using sec-O-glucosylhamaudol, the compound showed analgesia by the tail pressure and the Randall & Selitto methods, and its writhing inhibition was not reversed by naloxone.

Antinociceptive profile of hodgkinsine

To further understand the mechanism of analgesic activity and structural requirements of pyrrolidinoindoline alkaloids identified in Psychotria colorata, we here report the analgesic activity of the trimer hodgkinsine on thermal and chemical models of analgesia. Results show that hodgkinsine produces a dose-dependent naloxone reversible analgesic effect in thermal models of nociception, suggesting that activation of opioid receptors participates in hodgkinsine's mode of action. Hodgkinsine shows a potent dose-dependent analgesic activity against capsaicin-induced pain, indicating the participation of NMDA receptors in hodgkinsine-induced analgesia. Such a dual mechanism of action may be of interest for developing innovative analgesics.

[Pharmacological studies of trilex on treatment of pharyngitis]

Trilex consisted of three species: Ilex latifolia, Ilex asprella and Ilex rotunda. Trilex had the antipyretic effects, decreased the rat body temperature about 0.8 degree C on yeast induced hyperthermia. Trilex could obviously enhance the threshold of hot plate induced pain in mice. The maximum threshold increased 43.8%. Trilex could also inhibit acetic acid induced inflammatory ooze in mice abdominal cavity. The inhibitory rate was 34.8%. These results showed that trilex had antipyretic, analgesic and anti-inflammatory effects. It could be used to treat acute and chromic pharyngitis.

Anti-inflammatory, analgesic activity and acute toxicity of Sida cordifolia L. (Malva-branca)

Sida cordifolia L. (Malvaceae) is used in folk medicine for the treatment of inflammation of the oral mucosa, blenorrhea, asthmatic bronchitis and nasal congestion. The anti-inflammatory, analgesic effects and acute toxicity of an aqueous extract of S. cordifolia were evaluated in animal models. The extract was prepared using leaves collected before the flowering period. The aqueous extract (AE) showed a significant inhibition of carrageenin-induced rat paw edema at a dose of 400 mg/kg administered orally, but did not block the edema induced by arachidonic acid. The AE also increased the latency period for mice in the hot plate test, and inhibited the number of writhes produced by acetic acid at the oral dose of 400 mg/kg. The aqueous extract of S. cordifolia showed low acute toxicity in mice.

Antiplasmodial, analgesic, and anti-inflammatory activities of the aqueous extract of the stem bark of Erythrina senegalensis

The in vivo antiplasmodial, analgesic and anti-inflammatory properties of Erythrina senegalensis, an ornamental plant commonly used in Northern Nigeria for the treatment of fevers, was evaluated. Aqueous extracts of the stem bark of the plant was used for the study. The in vivo antiplasmodial activity of the aqueous extract against Plasmodium berghei was assessed using the suppressive and curative test procedures. Analgesic activity was assessed using the acetic acid (0.75%v/v) induced abdominal constriction, while the anti-inflammatory activity was evaluated on egg-albumin induced paw oedema in rats as a model of acute inflammation. The stem bark extract of E. senegalensis exhibited only slight antiplasmodial activity while significant (P<0.05) analgesic and anti-inflammatory effects were observed. Preliminary phytochemical analysis of the extract indicates the presence of alkaloids and glycosides.

Studies on the anti-inflammatory, antipyretic and analgesic properties of Alstonia boonei stem bark

The methanol extract of the stem bark of Alstonia boonei was investigated for anti-inflammatory property. The analgesic and antipyretic properties of the extract was also evaluated. The extract caused a significant (P<0.05) inhibition of the carrageenan-induced paw oedema, cotton pellet granuloma, and exhibited an anti-arthritic activity in rats. Vascular permeability induced by acetic acid in the peritoneum of mice was also inhibited. The extract also produced marked analgesic activity by reduction of writhings induced by acetic acid, as well as the early and late phases of paw licking in mice. A significant (P<0.05) reduction in hyperpyrexia in mice was also produced by the extract. This study has established anti-inflammatory, analgesic and antipyretic activities of the stem bark of A. boonei.

Tecoma sambucifolia: anti-inflammatory and antinociceptive activities, and 'in vitro' toxicity of extracts of the 'huarumo' of peruvian incas

Aqueous and alcoholic extracts of pods and flowers of Tecoma sambucifolia H.B.K. (Bignoniaceae) ('huarumo') were analysed to determine their anti-inflammatory activity (carrageenan-induced edema test), antinociceptive activity (acetic acid writhing test) and 'in vitro' toxicity in Chinese hamster ovary cells, human hepatome cells and human larynx epidermal carcinoma cells. The cytotoxic effects of both extracts were evaluated by two endpoint systems: neutral red uptake assay and tetrazolium assay. The results showed that all extracts have anti-inflammatory and antinociceptive activity, but the highest potency is that of the alcoholic extracts. There were significant differences in cytotoxicity between extracts and among the response of cells to them. The highest cytotoxicity was noted with the alcoholic extract, and the human hepatome cell line was the most sensitive, especially to the alcoholic extract of flowers. The aqueous pod extract appeared to have the best pharmaco-toxicological profile, since it provided a significant reduction of both pain and inflammation together with the lowest cytotoxicity.

Antinociceptive activity of I3,II8-binaringenin, a biflavonoid present in plants of the guttiferae

This paper describes the antinociceptive action of 13,118-binaringenin (GB-1a), a biflavonoid isolated from Clusia columnaris and present in several plants of the family Guttiferae, in a writhing test and a formalin test. It was found that it exhibits potent and dose-related antinociceptive action in both experimental models, with ID50 values of 22 mumol/kg against the writhing test and 28 mumol/kg against the second phase of the formalin test. It was more potent than some well-known analgesic drugs used as reference. Based on a hot-plate test its mechanism of action seems to be unrelated with the opioid receptors.

Ethnomedicinally selected plants as sources of potential analgesic compounds: indication of in vitro biological activity in receptor binding assays

A number of plant species used in traditional medicine for the relief of pain have been selected from the medicinal and scientific literature of China, South America, Asia and West Africa. Extracts were prepared and tested in three in vitro receptor radioligand binding assays to determine whether there was an indication of biological activity, in particular their selectivity to a single receptor implicated in the mediation of pain. The three neuropeptide receptors chosen were Bradykinin (BK II), expressed in Chinese hamster ovary cells (CHO), neurokinin 1 (NK 1) expressed in astrocytoma cells, and calcitonin gene related peptide (CGRP) which were all implicated in the mediation of acute pain in the mammaliancentral nervous system. The plant species chosen to investigate were Ageratum conyzoides, Barringtonia edulis, Croton tiglium, Ipomea pes-caprae, Panax ginseng, Physostigma venenosum, Sinomenium acutum, Solidago virgaurea, Symplocos leptophylla and Typhonium giganteum. The results showed that there was a strong indication of biological activity for some of the plants which are used ethnomedicinally to treat pain, in the three in vitro receptor binding assays used, and particular plant extracts exhibited selective action to a single receptor.

Chiral discrimination of the analgesic cizolirtine by using cyclodextrins: A (1)H NMR study on the solution structures of their host-guest complexes

The use of four cyclodextrins (three native and one beta-CD derivative) as NMR chiral solvating agents to resolve the enantiomers of (+/-)-cizolirtine, 1, and its chemical precursor (the carbinol, (+/-)-2), was investigated. The best enantiodiscrimination occurred when beta-cyclodextrin was used. ROESY experiments were performed to qualitatively ascertain the most probable host-guest structures in D(2)O solution, and the binding features found were explained in terms of spatial fitting of the guest molecules into the macrocyclic cavities. No geometrical differences were noted between the two diastereomeric complexes formed by a cyclodextrin and a racemic substrate, so the magnetic nonequivalence induced on guest protons by the enantioselective binding had to be explained as a result of subtle disparities in the orientation and/or the conformational state of the complexed enantiomers.

Strong antinociceptive effect of incarvillateine, a novel monoterpene alkaloid from Incarvillea sinensis

Incarvillea sinensis is a wild plant distributed in northern China. The dried whole plant has been traditionally used to treat rheumatism and relieve pain as an ancient Chinese crude drug. To investigate its antinociceptive activity, we evaluated several fractions derived from the methanolic extract of Incarvillea sinensis in the formalin-induced pain model in mice. Incarvillateine, a novel monoterpene alkaloid, has been found to show significant antinociceptive activity. Here we report the antinociceptive activity of incarvillateine and compare its activity with that of morphine. Additionally, we suggest that its action may be related to influence on the central opioid pathways.