Rafeeq Alam Khan

Anticonvulsant activities of nutmeg oil of Myristica fragrans.

The purpose of this study was to investigate the anticonvulsant activity of the volatile oil of nutmeg, the dried seed kernel of Myristica fragrans Houtt, using well‐established animal seizure models and to evaluate its potential for acute toxicity and acute neurotoxicity. The volatile oil of nutmeg (nutmeg oil) was tested for its effects in maximal electroshock, subcutaneous pentylenetetrazole, strychnine and bicuculline seizure tests. All the experiments were performed at the time of peak effect of nutmeg oil. Nutmeg oil showed a rapid onset of action and short duration of anticonvulsant effect. It was found to possess significant anticonvulsant activity against electroshock‐induced hind limb tonic extension. It exhibited dose dependent anticonvulsant activity against pentylenetetrazole‐induced tonic seizures. It delayed the onset of hind limb tonic extensor jerks induced by strychnine. It was anticonvulsant at lower doses, whereas weak proconvulsant at a higher dose against pentylenetetrazole and bicuculline induced clonic seizures. Nutmeg oil was found to possess wide therapeutic margin, as it did not induce motor impairment when tested up to 600 µL/kg in the inverted screen acute neurotoxicity test. Furthermore, the LD50 (2150 µL/kg) value was much higher than its anticonvulsant doses (50–300 µL/kg). The results indicate that nutmeg oil may be effective against grand mal and partial seizures, as it prevents seizure spread in a set of established animal models. Slight potentiation of clonic seizure activity limits its use for the treatment of myoclonic and absence seizures. Copyright

Anti inflammatory effect of natural honey on bovine thrombin-induced oxidative burst in phagocytes

Thrombin, hyperglycemia and reactive oxygen species (ROS) have been discovered to play a pivotal role in the pathogenesis of cardiovascular disease (CVD). The aim of the study was to evaluate the direct effect of bovine thrombin (BTh) on ROS production by human neutrophils and rodent macrophages and to investigate the effect of honey on BTh‐induced ROS production from phagocytes.

The analgesic, anti-inflammatory and calcium antagonist potential of Tanacetum artemisioides

Several species of the genusTanacetum are traditionally used in a variety of health conditions including pain, inflammation, respiratory and gastrointestinal disorders. In the current investigation, we evaluated the plant extract ofT. artemisioides and some of its pure compounds (flavo-noids) for analgesic, anti-inflammatory and calcium antagonist effects in variousin- vivo andin vitro studies. Using the actetic acid induced writhing test, intraperitoneal (i.p) administration of the plant extract (25-50 mg/kg) and its flavonoid compounds TA-1 and TA-2 (1-5 mg/kg ) exhibited significant analgesic actvity. The maximum analgesic effect observed with the crude extract of the plant was 71 % at 50 mg/kg, while that of compounds TA-1 and TA-2 (5 mg/kg i.p) was 75 and 47%, respectively. The plant extract and its pure compounds caused inhbition of formalin induced paw licking in mice predominatly in the second phase of the test. Diclofenac sodium, a standard reference compound, showed a simlar effect in these chemical induced pain models. In the carrgeenan induced rat paw edema assay, the plant extract (50-200 mg/kg i.p) demonstrated significant (P< 0.01) anti-inflmmatory activity which was comparable to that obtained with diclofenac sodium and indomethacin. In isolated rabbit jejunum preprations the plant extract showed an atropine sensitive dose-dependent (0.10-1.0 mg/mL) spasmogenic activity followed by a spasmolytic effect at the next higher doses (3-5 mg/mL). The crude extract of the plant also inhibited the high K+-induced contractions, indicating a calcium channel blocking (CCB) activity, which was further confirmed when the plant extract caused a right-ward shift in the Ca++ concentration response curves in the isolated rabbit jejunum preparations, similar to that seen with Verapamil. The flavonoid compounds isolated from the plant were devoid of any activity in the isolated tissue preparations. These results indicate that the plant extract ofT. artemisioides possesses analgesic, anti-inflammatory and CCB activities. The flavonoid compounds of the plant may have a role in its observed analgesic and anti-inflammatory activities, while the CCB activity of the plant may be attributed to some other chemical constituents present. Moreover the findings support the traditional reputation of the genusTanacetum for its therapeutic benefits in pain and inflammatory conditions.

Presence of blood-pressure lowering and spasmolytic constituents in Buddleja crispa.

This aim of this study was to investigate the crude extract of Buddleja crispa (Bc.Cr) and its active constituent(s) for their antihypertensive and antispasmodic activities. The Bc.Cr caused a dose‐dependent (3–10 mg/kg) fall in mean arterial pressure in rats under anesthesia. In rabbit aorta preparations, Bc.Cr (0.03–1 mg/mL) caused inhibition of high K+ (80 mM) precontractions. The Bc.Cr (0.03–1 mg/mL) also inhibited spontaneous and high K+ precontractions in rabbit jejunum preparations, suggestive of calcium channel blocking (CCB) activity. CCB activity was further confirmed when pretreatment of the tissues with Bc.Cr (0.03–0.10 mg/mL) caused a rightward shift in Ca++ concentration response curves, similar to verapamil. Among the pure compounds, BdI‐H3 was more potent against the high K+ than spontaneous contractions and was around eight times more potent than Bc.Cr against the spontaneous contractions while the other two compounds, BdI‐2 and BH‐3 were inactive. Activity‐directed fractionation revealed that the hexane fraction was more potent against K+ precontractions. These data indicate that Bc.Cr possesses a blood‐pressure lowering effect, mediated possibly through CCB, though additional mechanism(s) cannot be ruled out. Among the pure compounds, Bdl‐H3 is likely to be the active compound involved in the spasmolytic and possibly BP lowering effect of the parent crude extract. Copyright

Over prescription of antibiotics for adult pharyngitis is prevalent in developing countries but can be reduced using McIsaac modification of Centor scores: a cross-sectional study.

BackgroundAlthough Group A beta hemolytic streptococcus (GABHS) can cause bacterial pharyngitis, the most common etiology is viral; despite this viral etiology, antibiotics are commonly prescribed for this infection in industrialized countries. We investigated the prevalence of GABHS in adult pharyngitis patients from lower socioeconomic settings in Karachi, Pakistan, how often antibiotics are prescribed for pharyngitis and if appropriate agents were used in a developing world setting. Finally, we wanted to see the usefulness of modified McIsaac scores in predicting positive cultures.MethodsAdult patients were recruited from three local hospital outpatient dispensaries (OPDs). All patients aged 14–65 years who were suspected of having bacterial pharyngitis had throat swabs taken. Laboratory results for GABHS pharyngitis were then compared with their prescriptions. Appropriateness (using the World Health Organization’s definition) and type of antibiotic prescribed were assessed.ResultsOf 137 patients, 30 patients each were studied for scores of 0, 1, 2 and 3; 17 patients were studied for score 4. Although 6 (4.4%) patients were GABHS+, for a prevalence of 43.8 per 1000 population, antibiotics were prescribed to 135 patients (98.5%). Of these, only 11.1% received appropriate antibiotics while 88.9% received inappropriate antibiotics. Penicillins were prescribed most (34.1%), especially amoxicillin/clavulanate; followed by macrolides (31.1%), especially the second-generation agents, and fluoroquinolones (14.8%). McIsaac scores were found to be 100% sensitive and 68.7% specific, giving a positive predictive value (PPV) of 12.7% and a negative predictive value (NPV) of 100%.ConclusionsAntibiotics were prescribed irrationally to adult pharyngitis patients, as most cultures were negative for bacterial infection. McIsaac modification of Centor scores related directly to culture results. We would therefore highly recommend its use to help family physicians make treatment decisions for adult pharyngitis patients.

Antitussive and toxicological evaluation of Vitex negundo.

Vitex negundo Linn. (Verbenaceae) is used in traditional medical system for respiratory disorders. This study was carried out to investigate its cough-relieving potential. The antitussive effect of the butanolic extract of V. negundo (Vn) on sulphur dioxide (SO2)-induced cough was examined in mice. Safety profile of Vn was carried out by observing acute neurotoxicity, median lethal dose (LD50) and behavioural signs. Vn dose-dependently (250–1000 mg kg−1) inhibited the cough provoked by SO2 gas in mice and exhibited maximum protection after 60 min of administration. At 1000 mg kg−1, Vn caused maximum cough-suppressive effects i.e. cough inhibition at 60 min was 67.4%, as compared to codeine (10 mg kg−1), dextromethorphan (10 mg kg−1) and saline having cough-inhibitory potential 75.7%, 74.7% and 0%, respectively. LD50 value of V. negundo was found to be greater than 5000 mg kg−1. In toxicity tests, no signs of neural impairment and acute behavioural toxicity were observed at antitussive doses and extract has been well tolerated at higher doses. These results indicate that V. negundo exhibits antitussive effect and it was found devoid of toxicity.

Anticoagulant, antiplatelet and antianemic effects of Punica granatum (pomegranate) juice in rabbits.

Pomegranate (Punica granatum L., Punicaceae) is a good source of minerals and phytochemicals with diverse pharmacological activities such as anxiolytic, antidepressant, hypoglycemic, hypolipidemic, and anti-inflammatory activities. Effects of P. granatum on blood parameters and coagulation have, however, been little studied. The aim of the study was to assess the outcome of P. granatum on coagulation and anticoagulation factors at different doses on blood samples of healthy white rabbits. Blood samples of the animals were collected twice during the study and biochemical assays were performed to assess the effect on hematological, coagulation, anticoagulation, and platelet aggregation. Significant changes were observed in erythrocytes, hemoglobin, and mean corpuscular hemoglobin concentration, while bleeding and thrombin time were also prolonged significantly. There was significant increase in protein C, thrombin antithrombin complex levels, and decrease in platelet aggregation and fibrinogen concentration, in a dose-dependent manner. The results of hematological and coagulation assays lead to the speculation about a possible antianemic and cardioprotective effect of P. granatum.

Hypolipidemic and antithrombotic evaluation of Myrtus communis L. in cholesterol-fed rabbits

Herbs have been a great source of natural substances used to prevent many cardiovascular diseases (CVD). Blood lipid levels and coagulation parameters are probably the major determinant for producing CVDs. The present study was undertaken to evaluate the hypo-lipidemic and anti-thrombotic activities of aqueous extract of Myrtus communis L. fruit (AEM) in cholesterol-fed rabbits. Hyper-lipidemia was induced following administration of cholesterol for 45 days. Animals of treated group were administered AEM daily for 30 and 45 days at dose of 50 mg/kg. Biochemical tests were performed at the end of dosing that is, on 31st day and again on 46th day. The administration of AEM (50 mg/kg/day) revealed reduction in serum triglycerides and low density lipoprotein; there was also an increase in thrombin and fibrinogen time. Results of present study indicate that the extract exhibited hypolipidemic effects and has also an effect on blood coagulation parameters which may be of value in CVDs. However, further studies are necessary to explore the precise mechanism of action of these effects. Key words: Herbs, lipid profile, blood coagulation, rabbits.

Antitussive Efficacy and Safety Profile of Ethyl Acetate Fraction of Terminalia chebula

Antitussive effects of ethyl acetate fraction of Terminalia chebula on sulphur dioxide (SO2) gas induced cough have been examined in mice. Safety profile of Terminalia chebula was established by determining LD50 and acute neurotoxicity. The result showed that extract of Terminalia chebula dose dependently suppressed SO2 gas induced cough in mice. Terminalia chebula, after i.p. administration at dose level 500 mg/kg, offered maximum cough suppressive effects; that is, number of coughs at 60 min was 12 ± 1.52 (mean ± SEM) as compared to codeine 10 mg/kg; i.p., dextromethorphan 10 mg/kg; i.p., and saline, having frequency of cough 10.375 ± 0.866, 12.428 ± 0.81, and 46 ± 2.61, respectively. LD50 value of Terminalia chebula was approximately 1265 mg/kg, respectively. No sign of neural impairment was observed at antitussive doses of extract. Antitussive effect of Terminalia chebula was partly reversed with treatment by naloxone (3 mg/kg; s.c.) while rimcazole (3 mg/kg; s.c.) did not antagonize its cough suppression activity. This may suggest that opioid receptors partially contribute in antitussive action of Terminalia chebula. Along with this, the possibility of presence of single or multiple mechanisms activated by several different pharmacological actions (mainly anti-inflammatory, antioxidant, spasmolytic, antibacterial, and antiphlegmatic) could not be eliminated.

Investigation of antitussive and toxicological activity of Ballota limbata in mice.

Context: Ballota limbata Benth. (Lamiaceae) (syn, Otostegia limbata Hook.f.) is a species grown in the North West Frontier Province and the lower hills of West Punjab, Pakistan. Ballota species are renowned for their antispasmodic, antiulcer, diuretic, vermifuge, and especially sedative effects. However, little is known about the biological activity of B. limbata. Objective: Evaluation of antitussive activity and safety profile of dried B. limbata extract. Materials and methods: Whole air-dried plants were partitioned with various solvents and the butanol fraction was subjected to antitussive evaluation using a sulfur dioxide (SO2)-induced cough model in mice. Codeine and dextromethorphan were used as positive control. Safety profile of the testing material was established using standard toxicity tests. Results: B. limbata extract inhibited cough provoked by SO2 gas in mice in a dose-dependent manner. The extract exhibited maximum protection against SO2-induced cough after 60 min of administration. B. limbata offered maximum cough suppressive effects, that is, number of coughs during 60 min was 11.66 ± 1.2 (mean ± SEM), after s.c. administration of 800 mg/kg, as compared with codeine 10 mg/kg, s.c., dextromethorphan 10 mg/kg, s.c., and saline showing a frequency of cough of 11.75 ± 1.18, 12.25 ± 0.83, and 46.25 ± 1.52, respectively. LD50 value of B. limbata was greater than 5000 mg/kg. No sign of neural impairment was observed at antitussive doses and the extract has been well-tolerated at higher doses. Discussion and conclusion: This study demonstrates that the extract of B. limbata has shown strong cough suppressive effect in mice without yielding any notable toxicity.