Potential Antidepressant Constituents of Nigella sativa Seeds.

BACKGROUND: Nigella sativa Linn. is well known seed in the Middle East, Asia, and the Far East as a natural remedy for many ailments and as a flavoring agent proclaimed medicinal usage dating back to the ancient Egyptians, Greeks, and Romans. An authentic saying of the Prophet Muhammad (Peace Be Upon Him) about black seed is also quoted in Al-Bukhari. OBJECTIVE: This study was carried out to evaluate the antidepressant effect and isolate the potential antidepressant constituents of the polar extract of N. sativa seeds. MATERIALS AND METHODS: The antidepressant effect was evaluated through the immobility duration in tail suspension and forced swim tests (FSTs). Albino mice were orally treated with N. sativa polar extract and its RP-18 column chromatography fractions (50 and 100 mg/kg,). RESULTS: The polar extract and two of its sub-fractions were significantly able to decrease the immobility time of mice when subjected to both tail suspension and FSTs, the effects are comparable to standard drug (Sertraline, 5 mg/kg). However, these treatments did not affect the number of crossings and rearing in the open field test. Phytochemical investigation of the two active fractions led to the isolation of quercetin-3-O-α-L-rhamnopyranoside 1, quercetin-7-O-ß-D-gluco- pyranoside 2, tauroside E 3, and sapindoside B as the potential antidepressant constituents. SUMMARY: Phytochemical and biological evaluation the antidepressant constituents in Nigella sativa using the tail suspension and forced swim methods afforded the isolation and identification of quercetin-3-O-α-L rhamnopyranoside, quercetin-7-O-ß-D gluco pyranoside, tauroside E, and sapindoside B as the potential antidepressant constituents in the polar extract of N. sativa. The isolated compounds were identified through extensive NMR analysis (1D, 2D, ESI MS). Abbreviations used: TST: Tail suspension test, FST: Forced swim test, OFT: An Open field test.

The current status of beta blockers' use in the management of hypertension.

The invention of beta (ß)-blockers culminated in a new era in the treatment of cardiovascular diseases (CD), and changed the course of pharmacology research for years to come. Since the introduction of propranolol into clinical practice in 1964, ß-blockers enjoyed a special place in the clinicians' armamentarium against CDs, especially for patients with ischemic heart diseases, and are still one of the most extensively used therapeutic drugs in both cardiac and non-cardiac ailments. Current uses of ß-blockers in CDs include ischemic heart diseases, hypertension, cardiac arrhythmias, and heart failure. Other substantial non-cardiac uses include glaucoma, migraine, situational anxiety, benign essential tremors, and cardiac symptoms of thyrotoxicosis. This review covers some of the evolutionary changes of clinical uses of ß-blockers, the rationale for their use, some recent controversies surrounding their use for treatment of hypertension, and advantages of newer additions to the group. 

Potentiation of Valproate-induced Anticonvulsant Response by Nigella sativa Seed Constituents: The Role of GABA Receptors.

This study investigated antiepileptic effects of the main constituents of Nigella sativa (NS) seed (i.e. aqueous extract (AE), fixed oil (FO), volatile oil (VO)) and the main components of its VO (i.e. thymoquinone, α-pinene and p-cymene) using pentylenetetrazole (PTZ) and maximal electroshock (MES)-induced convulsions. The potential of these constituents to induce minimal neurological deficit (MND) was also evaluated by using chimney test.Except for the FO, all of the NS seed constituents protected mice effectively against PTZ-induced convulsions. The activity of the VO in this model maybe attributed mainly to its content of thymoquinone and p-cymene and to a lesser extent, α-pinene. VO and its component p-cymene effectively suppressed convulsions induced by MES. The contents of p-cymene present in the effective dose of the VO maybe partially responsible for its anti-seizure effects.All of the NS seed constituents induced varying degrees of MND in the chimney test. MND induced by VO may pertain to its contents of thymoquinone (63%), p-cymene (23%) and α-pinene (<14%). Protective indices of p-cymene and thymoquinone were closer to one, but only in PTZ model.Exploration on the role of receptors suggests that picrotoxin and bicuculline-sensitive GABA receptors, most probably GABAA receptors, mediate an increase in GABAergic response. In the part dealing with the interaction of valproate with thymoquinone, it can be mentioned that thymoquinone increased the potency of valproate in both PTZ and MES models.

Synthesis of a new series of substituted pyrimidines and its evaluation for antibacterial and antinociceptive effects.

BACKGROUND: Pyrimidines are a well known group of compounds reported to have different biological activities. Prompted from the diversity of its wider use and being an integral part of genetic material, an effort was made to synthesize a novel series of amino-pyrimidine derivatives of pharmaceutical interest by condensing the guanidinyl derivative of nalidixic acid with different chalcones. METHODS: The structures of all synthesized compounds were established on the basis of IR and 1HNMR spectral studies. All of the new compounds in this series were screened for antimicrobial activity. Gram +ve and Gram -ve strains were used to ascertain the spectrum of activity. ED50 values in the tail flick test were determined and recorded. Analgesic potential of compounds by using tail flick test in SWR male mice have also revealed promising results. RESULTS: All of the derivatives were effective in Gram -ve test against E. coli. None of the compounds show any inhibition of Gram +ve strain S. aureus. m-Bromo substitution derivative of amino-pyrimidines showed appreciable activity against E. coli, while 2,4 dichloro and p-chloro substitution derivatives also demonstrated improved activity. Compound 4 was most potent. The order of potency for these derivatives was 4>5≥6>1>2>7>3. Parallel to antimicrobial activity, m-bromo substitution derivative showed significant (P<0.01) antinociceptive response in comparison to control, and this effect was comparable to aspirin group. Trimethoxy substitution of benzene ring demonstrated moderate activity, whereas p-bromo substitution essentially had no antinociceptive effects in mice. CONCLUSION: Comparing meta- and para- bromo substitutions, there had been significant (P<0.01) difference in the antinociceptive response of both the bromo-substituted derivatives. It was observed that bromo-substitution at meta- position demonstrated comparatively higher potential for its antibacterial as well as antinociceptive properties.

Evaluation of ambrein and epicoprostanol for their antioxidant properties: protection against adriamycin-induced free radical toxicity.

Ambrein and epicoprostanol were evaluated for their antioxidant potential in vitro by chemiluminescence (CL), as well as in vivo using lipid peroxides and glutathione levels as indicators in liver tissue of rats treated with adriamycin (doxorubicin) a well known free radicals producing drug. In the in vitro test, the inhibition in CL by ambrein was dose dependent. Both the high concentrations of ambrein (20-40 microg/ml) inhibited CL response significantly (P<0.05 and P<0.01, respectively) when compared to control. Similarly two low concentrations (5-20 microg/ml) of epicoprostanol inhibited CL significantly (P<0.001 and P<0.01, respectively) in comparison of DMSO control. The high concentration (40 microg/ml) of epicoprostanol behaved exceptionally and caused an increase in CL response that was more than control and significantly (P<0.001) higher than both the low concentrations. In the in vivo studies adriamycin treatment significantly (P<0.05) increased malondialdehyde (MDA) and decreased non-protein sulfhydryl (NP-SH) contents in the liver tissue of mice after 5 days treatment. Ambrein (25 and 50 mg/kg) treatment as a solo therapy at both the dose levels significantly (P<0.001) decreased MDA contents in the liver tissue. On the other hand, in the combined treatment the high dose effectively prevented any rise in MDA contents and it remained around the levels of ambrein alone. In the same experiment, adriamycin declined NP-SH contents significantly (P<0.001). Ambrein alone at both the dose levels caused a decline (P<0.01) in NP-SH contents when compared to adriamycin group. But in the combined treatment this decline in NP-SH was significantly (P<0.05) different from adriamycin alone. In the experiments dealing with epicoprostanol, adriamycin treatment increased MDA contents significantly (P<0.05) that declined significantly (P<0.001) with epicoprostanol (10- or 20mg/kg) treatment. In the same experiment co-treatment with adriamycin prevented any rise in MDA contents significantly (P<0.001) as it was observed in adriamycin alone group. Although, this treatment failed to prevent any decline in NP-SH contents either alone or in combination with adriamycin. Epicoprostanol itself had the comparative declining effect on the contents of NP-SH as seen in adriamycin group. From the results of our experiments it seems that ambrein at all concentrations behaves like antioxidant in in vitro studies but the same time it decreased NP-SH contents in vivo accompanied by a decline in MDA contents. Whereas, epicoprostanol at two low concentrations had a decline in CL indicating a possible antioxidant potential but the high concentration increased CL showing a tendency towards oxidant prospective. However, in animal studies it has shown a clear protection against adriamycin induced free radical damage.