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Biomedical subjects

F Ionescu

Publications and source records attributed to F Ionescu.

13 recordsLinked to original sources
PubMed1978

Plant anticancer agents V: new bisindole alkaloids from Tabernaemontana johnstonii stem bark.

The isolation and structure elucidation of the three new bisindole alkaloids, gabunamine, tabernamine, and 19,20-epoxyconoduramine, from Tabernaemontana johnstonii stem bark are described. The isolation of the seven known alkaloids, conodurine, conoduramine, gabunine, isovacangine, ibogamine, pericyclivine, and perivine, from the same source also is noted. The alkaloids gabunamine, gabunine, and tabernamine showed significant cytotoxicity against the P-388 cell culture system.

Alkaloids↗
PubMed1977

Plant anticancer agents III: Isolation of indole and bisindole alkaloids from Tabernaemontana holstii roots.

Certain active antileukemic and cytotoxic fractions prepared from Tabernaemontana holstii roots were investigated, resulting in the isolation of the known indole alkaloids conoduramine, conodurine, coronaridine, gabunine, 19-oxocoronaridine, pericyclivine, perivine, and vobasine. Two new alkaloids were assigned the structures 19-oxoconodurine and 19-(2-oxopropyl)conodurine. Both gabunine and 19-(2-oxopropyl)conodurine showed significant inhibitory activity against P-388 cell culture. All of the alkaloids are reported for the first time from T. holstii; conodurine, conoduramine, gabunine, perivine, and pericyclivine are reported for the first time from any Tabernaemontana species.

Alkaloids↗
PubMed1977

Application of the Free-Wilson technique to structurally related series of homologues. Quantitative structure-activity relationship studies of narcotic analgetics.

A series of benzomorphans with ED50 values determined in vivo by the hot-plate method in mice is analyzed by the modified Free-Wilson method. The QSAR yields 36 substituent constants (ai) with contributions to the overall activity in agreement with experimental data. Substituent constant values obtained for benzomorphans are used in calculating log (1/C) values for six morphinans. An excellent correlation is obtained (r = 0.95) between the six calculated and observed activities. The possibility of extending the Free-Wilson approach from one series of homologues to another is demonstrated.

Analgesics, Opioid↗
PubMedDate not supplied

Hydroalcoholic plant extracts with anti-inflammatory activity.

The aim of the present study was to investigate if standardized hydroalcoholic plant extracts such as Calendula officinalis, Hypericum perforatum, Plantago lanceolata and Glycyrrhiza glabra can suppress in cell-free systems the activities of 5-lipoxygenase (5-LO) and cyclooxygenase-2 (COX-2), key enzymes in the formation of proinflammatory eicosanoids from arachidonic acid (AA). Studies were undertaken to compare the above mentioned plant extracts to a known NSAID (nimesulide) in their ability to inhibit both cyclooxygenase (COX-2) and lipoxygenase (5-LO) activities in cell-free systems. We report on 2 vegetal extracts (Hypericum perforatum and Glycyrrhiza glabra) that inhibit 5-LO activity and 2 vegetal extracts (Plantago lanceolata and Glycyrrhiza glabra) that inhibit COX-2 activity. In this study, we demonstrate for the first time that Glycyrrhiza glabra extract efficiently suppresses both eicosanoids and leukotrienes formation in cell-free systems, implying that this extract directly acts as a dual inhibitor of 5-LO and COX-2 activities. With regard to the properties of dual COX-2/5-LO inhibitors, Glycyrrhiza glabra extract might be a potential drug possessing anti-inflammatory activity devoid of the most troublesome (gastric) side effects seen for drugs used as COX-2 and 5-LO inhibitors. Hypericum perforatum, Plantago lanceolata and Glycyrrhiza glabra extracts can be added to an already impressive list of these species that have anti-inflammatory activity.

Anti-Inflammatory Agents↗
PubMedDate not supplied

Antioxidant properties of some hydroalcoholic plant extracts with antiinflammatory activity.

The hydroalcoholic extracts of Calendula officinalis, Hypericum perforatum, Plantago lanceolata and Glycyrrhiza glabra which exhibited different anti-inflammatory activities were evaluated for the possible mode of action by studying their antioxidant potential. In the present study we investigated if standardized hydroalcoholic extracts of plants such as Calendula officinalis, Hypericum perforatum, Plantago lanceolata and Glycyrrhiza glabra produced by Hofigal Stock Company could modulate the respiratory burst of human activated neutrophils, as a consequence of their antioxidant capacity. Their antioxidant properties were measured using a colorimetric assay (Total Antioxidant Status kit). We demonstrated that Hypericum perforatum and Calendula officinalis hydroalcoholic extracts possessed a significant antioxidant activity while Plantago lanceolata and Glycyrrhiza glabra hydroalcoholic extracts had a minor antioxidant status. Using reactive oxygen species-generating systems (OZ-activated human PMN neutrophils), Calendula officinalis and Hypericum perforatum extracts showed strong reactive oxygen species scavenging property, Hypericum perforatum extract exhibing the highest scavenging activity. These results confirm the potential of Calendula officinalis and Hypericum perforatum investigated hydroalcoholic extracts as medicinal remedies to be used in different inflammatory/allergic diseases. These extracts could be a useful tool for obtaining new antioxidant/anti-inflammatory agents.

Anti-Inflammatory Agents↗