Tawat Taesotikul

ANTI-INFLAMMATORY, ANTIPYRETIC AND ANTINOCICEPTIVE ACTIVITIES OF TABERNAEMONTANA PANDACAQUI POIR

Studies on carrageenin-induced rat paw edema, yeast-induced hyperthermia in rat and writhing response induced by acetic acid in mice showed that the alcoholic extract of stems of Tabernaemontana pandacaqui (T. pandacaqui) has significant anti-inflammatory, antipyretic and antinociceptive activities. These activities are due to alkaloidal components since they were also observed when the crude alkaloidal (CA) fraction separated from alcoholic extract was tested in the same models.

The analgesic, antipyretic and anti-inflammatory activity of Diospyros variegata Kruz

Pharmacological studies were conducted with the hexane extract of the dry stem of Diospyros variegata Kruz. (Ebenaceae) on experimental animals for evaluating the analgesic, antipyretic and anti-inflammatory activities. In the analgesic test, the hexane extract elicited inhibitory intensity on acetic acid-induced writhing response and on the late phase of formalin test but possessed only a weak effect on the tail-flick response and on the early phase of formalin test. The hexane extract also elicited antipyretic action when tested in yeast-induced hyperthermia in rats. In addition, the hexane extract showed an anti-inflammatory effect when tested in ethyl phenylpropiolate (EPP)- and arachidonic acid (AA)-induced rat ear edema.

Anti-inflammatory and antipyretic properties of Clerodendrum petasites S. moore

The methanol extract from Clerodendrum petasites S. Moore (CP extract) was assessed for anti-inflammatory and antipyretic activities on the experimental animal models. It was found that CP extract possessed moderate inhibitory activity on acute phase of inflammation in a dose-related manner as seen in ethyl phenylpropiolate-induced ear edema (ED(50)=2.34 mg/ear) as well as carrageenin-induced hind paw edema (ED(30)=420.41 mg/kg) in rats. However, CP extract did not elicit any inhibitory effect on arachidonic acid-induced hind paw edema in rats. In subchronic inflammatory model, CP extract provoked a significant reduction of transudation but had no effect on proliferative phase when tested in cotton pellet-induced granuloma model. CP extract also reduced the alkaline phosphatase activity in serum of rats in this animal model. Moreover, CP extract possessed an excellent antipyretic effect when tested in yeast-induced hyperthermic rats. It is postulated that the anti-inflammatory and antipyretic effects of CP extract are caused by the inhibition of the prostaglandin synthesis. Anyhow, CP extract did not possess any analgesic activity in acetic acid-induced writhing response in mice. The results obtained show that C. petasites has beneficial properties since it possesses potent antipyretic and moderate anti-inflammatory activities without ulcerogenic effect.

Hepatoprotective effects of lychee (Litchi chinensis Sonn.): A combination of antioxidant and anti-apoptotic activities

AIM OF THE STUDY Gimjeng and Chakapat lychee (Litchi chinensis Sonn.) were evaluated for hepatoprotective activity on CCl(4)-induced hepatotoxicity in rats. MATERIALS AND METHODS Fruit pulp extracts of the lychees were examined for vitamin C, phenolic contents, anti-lipid peroxidation activity and hepatoprotective effect. Male Wistar albino rats were intraperitoneally injected (ip) with CCl(4) (2 ml/kg), then were orally administered (po) with silymarin (100mg/kg), and Gimjeng or Chakapat extracts (100 and 500 mg/kg). After ten days, the rats were sacrificed and their livers were examined histopathologically and immunohistochemically. Their serum glutamate-pyruvate transaminase, glutamate-oxalate transaminase, and alkaline phosphatase activities were analyzed. Apoptotic activity of the livers was assessed quantitatively. RESULTS The Gimjeng and Chakapat extracts showed the contents of vitamin C (1.2±0.6 and 4.3±0.1mg/100g) and phenolics like trans-cinnamic acid and pelargonidin-3-O-glucoside (9.80±0.21 and 19.56±0.4 mg GAE/g extract, respectively), and trolox equivalent antioxidant capacity (TEAC) values (11.64 and 9.09 g/mg trolox), respectively. The Gimjeng as compared to the Chakapat demonstrated a better antioxidant activity as revealed by anti-lipid peroxidation activity with the TEAC values. Administration of CCl(4) in rats elevated the serum GPT, GOT, and ALP level whereas silymarin, Gimjeng and Chakapat extracts prevented these increases significantly. Significant decrease of apoptotic cells together with restoration of morphological changes confirmed the hepatoprotective effect in the CCl(4)-induced rats pretreated with the extracts. CONCLUSION Antioxidant properties of the Gimjeng and Chakapat lychees as evidenced by the vitamin C and phenolic compounds, anti-lipid peroxidation and anti-apoptosis could explain the hepatoprotective effects in CCl(4)-induced hepatotoxicity.

Neuropharmacological activities of the crude alkaloidal fraction from stems of Tabernaemontana pandacaqui Poir.

The crude alkaloidal (CA) fraction from the stem of Tabernaemontana pandacaqui Poir. was studied for its pharmacological activity on the central nervous system (CNS) of animals. The CA fraction was found to produce symptoms of CNS depression in conscious rats and mice, viz. reduction in spontaneous motility, potentiation of pentobarbital sleeping time, prolongation of latency of convulsions induced by pentylenetetrazole and antinociception. However, the fraction could not antagonize oxotremorine-induced tremor. The observations suggest that the CA fraction possesses a CNS depressant activity.

Isolation of opioid-active compounds from Tabernaemontana pachysiphon leaves.

A procedure for prefractionation of crude plant extracts by centrifugal partition chromatography (CPC) has been developed to enable rapid identification of known‐positive compounds or false‐positive compounds and to increase the chance of identifying minor unknown‐active compounds. The study explored the use of CPC as a tool in the prefractionation step before investigation of bioactivity.

Hippocratic screening of ethanolic extracts from two Tabernaemontana species

Ethanolic extracts of roots, stems, leaves and flowers of Tabernaemontana divaricata and T. pandacaqui were studied by an observational (hippocratic) screening method in rats. Extracts of all plant parts caused sedation, decreased respiration and decreased skeletal muscle tone. Except for the leaf extract of T. pandacaqui, the extracts caused vasodilatation of ear vasculature. Analgesic activity was found for all extracts of both Tabernaemontana species, except for the flower extract of T. divaricata. Lethal doses of the extracts caused the animals to die from respiratory paralysis. Intensity of pharmacological activities was greater with the root and stem extracts. The extracts of T. pandacaqui were more potent than those of T. divaricata.

Postcoital antifertility effect of Mentha arvensis

A uterotonic fraction of Mentha arvensis (UM-fraction) was tested for antifertility effect in rats. Subcutaneous administration of the UM-fraction to rats pregnant from day 1 to day 10 caused a significant interruption in pregnancy. The effect was pronounced during the post-implantation period. At the effective dose, the UM-fraction did not exhibit significant estrogenic or antigonadotropic activities. However, it enhanced the estrogenic effect of estradiol when administered concurrently.

Cardiovascular activity of the crude alkaloidal fraction from Tabernaemontana pandacaqui in the rat

The effects of a crude alkaloidal (CA) fraction from the stem of Tabernaemontana pandacaqui Poir. on the blood pressure and heart rate were investigated in conscious as well as anesthetized rats. The CA fraction exerted a hypotensive activity in both experimental models. In pentobarbital anesthetized rats, an intravenous administration of the CA fraction caused two consecutive hypotensive and bradycardiac responses. In order to investigate the mechanism of the responses, the effect of the CA fraction on the blood pressure and the heart rate was tested in various experimental animals such as pithed rats, reserpinized rats under pentobarbital anesthesia and atropine- or chlorpheniramine-treated rats under pentobarbital anesthesia. The results obtained suggest that the hypotensive and bradycardiac responses of the first phase might involve cholinergic and central mechanisms, whereas those of the second phase involve mechanisms which are mediated by central, biogenic amines, acetylcholine and histamine.

Ethnobotanical review of medicinal plants from Thai traditional books, Part II: Plants with antidiarrheal, laxative and carminative properties.

A survey of medicinal plants used in Thailand has been made from Thai books on traditional herbal medicine. In this part of the survey, 326 plants with antidiarrheal, laxative and/or carminative properties are described. Information provided for each species includes plant part used, methods of preparation and administration and literature references to Thai books, together with indications of usage in other Southeast Asian countries and of phytochemical work which has been performed.