Prostaglandin-like substances in Propionibacterium acnes II. Stimulatory effect on ovarian cyclic AMP.

The prostaglandin-like substances (PLS) from Propionibacterium acnes increased the ovarian tissue levels of cyclic AMP (cAMP) approximately 2-fold. The lipid material extracted from P. acnes thus behaved like PG's of the E-type, and since it is unlikely that other known stimulators of the ovarian cAMP system can be present in the bacterial lipid fraction, these experiments give further evidence in favour of the occurrence of PLS in P. acnes.     

The effect of acidic polysaccharides and prostaglandin-like substances isolated from Propionibacterium acnes on granulocyte chemotaxis.

Three acidic polysaccharide (AP) fractions and the prostaglandin-like substances (PLS) isolated from P. acnes were investigated regarding their chemotactic activities on polymorphonuclear leukocytes. Both AP's and PLS induced a significant chemotatic response, which suggests their involvement in inflammatory acne vulgaris.     

Prostaglandin-like substances inPropionibacterium acnes. V. Activity profiles using cascade superfusion bioassay and platelet aggregation

Summary The activity spectrum of prostaglandin-like substances (PLS) fromP. acnes was investigated with cascade superfusion technique and by platelet aggregation assay. The biological activity of PLS resembles that of PGI₂: both relax bovine coronary artery, rabbit mesentric and coeliac arteries; both contract the rat stomach strip as well as both typically inhibit spontaneous movements of isolated guinea pig ileum. Also, similarly to PGI₂, PLS inhibits platelet aggregation regardless the inducer used. However, PLS possesses a specific antiaggregatory pattern on platelet, which indicates that these compounds are not indentical with primary prostaglandins or PGI₂.     

Prostaglandin-like substances inPropionibacterium acnes. IV. Effect on isolated human vessels

Summary The present study demonstrates a powerful vasoconstrictor activity of prostaglandin-like substances (PLS), extracted fromP. acnes, on human blood vessels. PLS is about equipotent to PGE₂ in its effect on human umbilical vessels, but the contractile response pattern is different. PLS therefore seems to have specific and different physiological characteristics.     

Prostaglandin-like substances inPropionibacterium acnes II. Stimulatory effect on ovarian cyclic AMP

Summary The prostaglandin-like substances (PLS) fromPropionibacterium acnes increased the ovarian tissue levels of cyclic AMP (cAMP) approximately 2-fold. The lipid material extracted fromP. acnes thus behaved like PG's of the E-type, and since it is unlikely that other known stimulators of the ovarian cAMP system can be present in the bacterial lipid fraction, these experiments give further evidence in favour of the occurrence of PLS inP. acnes.     

Evidence that the prostaglandin-like substances fromPropionibacterium acnes are not identical with PGE2

Summary The prostaglandin-like substances (PLS) isolated fromP. acnes were investigated by reversed phase chromatography and gas chromatography-mass spectrometry. These analyses demonstrated that PLS were not identical with PGE₂, which supports a concept of PLS as a potential mediator of the inflammatory process in acne vulgaris.     

Prostaglandin-like substances inPropionibacterium acnes. VI. Characterization of the lipid fraction by gas chromatography in conjunction with mass spectrometry

Summary The lipid fraction ofP. acnes was submitted to stepwise purification followed by bioassay in order to localize the prostaglandin-like material. GC-MS analysis revealed the occurrence of substances having a part but not a total molecule in common with the prostaglandin family, suggesting that prostaglandin-like substances represent a new group of prostaglandin compounds.The competent technical assistance of Mr N. Engström and Mr G.A. de Vogel is gratefully acknowledged.     

The effect of acidic polysaccharides and prostaglandin-like substances isolated fromPropionibacterium acnes on granulocyte chemotaxis

Summary Three acidic polysaccharide (AP) fractions and the prostaglandin-like substances (PLS) isolated fromP. acnes were investigated regarding their chemotactic activities on polymorphonuclear leukocytes. Both AP's and PLS induced a significant chemotactic response, which suggests their involvement in inflammatory acne vulgaris.     

2-Phenylethanol, a presumed sexual stimulant produced by the male cabbage looper moth, Trichoplusia ni.

A sex pheromone produced by male cabbage looper moths, Trichoplusia ni (Hübner), has been isolated from the genital scent brushes and identified as 2-phenylethanol. It is shown conclusively to elicit specific behavioural responses in the female (such as wing vibration and abdominal elevation), as determined by a novel behavioural laboratory bioassay. This is taken as further evidence that the male pheromone of T. ni acts as a sexual stimulant (aphrodisiac) prior to mating. 2-Phenylethanol represents the first identification of a genital scent brush pheromone in the family Noctuidae, and of a male pheromone in the subfamily Plusiinae.     

Gain of function of TMEM16E/ANO5 scrambling activity caused by a mutation associated with gnathodiaphyseal dysplasia

Mutations in the human TMEM16E (ANO5) gene are associated both with the bone disease gnathodiaphyseal dysplasia (GDD; OMIM: 166260) and muscle dystrophies (OMIM: 611307, 613319). However, the physiological function of TMEM16E has remained unclear. We show here that human TMEM16E, when overexpressed in mammalian cell lines, displayed partial plasma membrane localization and gave rise to phospholipid scrambling (PLS) as well as non-selective ionic currents with slow time-dependent activation at highly depolarized membrane potentials. While the activity of wild-type TMEM16E depended on elevated cytosolic Ca²⁺ levels, a mutant form carrying the GDD-causing T513I substitution showed PLS and large time-dependent ion currents even at low cytosolic Ca²⁺ concentrations. Contrarily, mutation of the homologous position in the Ca²⁺-activated Cl^? channel TMEM16B paralog hardly affected its function. In summary, these data provide the first direct demonstration of Ca²⁺-dependent PLS activity for TMEM16E and suggest a gain-of-function phenotype related to a GDD mutation.     

Release of platelet activating factor (P.A.F.-acether) by isolated perfused rat kidney

Platelet-activating factor (a 1-0-alkyl-2-acetyl glyceryl-3-phosphorylcholine, P.A.F.-acether) causes the aggregation of platelets from various Mammalian species and the release of their granule content. P.A.F.-acether activity has been recovered in vitro from perfused isolated Rat kidneys, stimulated by the ionophore A 23187. The maximum release was reached 10 min. after addition of the ionophore. P.A.F.-acether from kidney exhibited the same physico-chemical and biological characteristics as P.A.F.-acether from leucocytes. These data demonstrate that the kidney secretes a mediator of immediate hypersensitivity (P.A.F.-acether) in the veinous vasculature. Therefore the kidney itself has the ability of inducing intravascular platelet aggregation with subsequent local increase in vasopermeability.     

Neuromuscular junction blocking agents: an initial screening bioassay

A simple, rapid and sensitive in vivo bioassay for the initial screening of neuromuscular junction (NMJ) blocking agents has been accomplished. The i.v. retro-orbital plexus (IVROP) mode of injection was utilized, for the first time, in conjunction with the mouse inclined screen bioassay.     

Remarks on the karyotype of the polypteriformes. The chromosomes ofPolypterus delhezi,P. endlicheri congicus andP. palmas

Summary The chromosomes of 3 species of bikirs (Polypterus delhezi, P. endlicheri congicus andP. palmas) were studied in somatic metaphases. The diploid number was found to be 2 n=36 in all the species and a basic morphological identity of the karyotype emerges from karyogram comparison not only in the 3 species described herein, but also in the other Polypteriformes already studied.     

Gonyauline: a novel endogenous substance shortening the period of the circadian clock of a unicellular alga

The circadian clock in the unicellular alga Gonyaulax polyedra is accelerated by a substance in extracts from the cells themselves. The extracts have been fractionated using the circadian rhythm of bioluminescence as bioassay. The active substance, termed gonyauline, has been isolated and characterized as a novel low molecular weight cyclopropanecarboxylic acid (S-methyl-cis-2-(methylthio) cyclopropanecarboxylic acid). Synthetic gonyauline has a similar shortening effect on the period of the circadian clock.     

Prostacyclin-like activity of endothelium and subendothelium - important for atherosclerosis?

Morphological control of Moncada's bioassay for prostacyclin (PG I2) activity measurement shows that the activity depends not only on endothelium, but in important amounts on subendothelial tissue too. Therefore, it can be concluded that platelet thrombus formation after endothelial cell injury does not depend only on the PG I2-producing ability of the tissue.     

Changes in the level of ACTH in the fetal hypophysis. A study in the rat toward the end of gestation]

The isolated adrenal cell method for bioassay of ACTH was employed in order to determine the ACTH content of the hypophysis of the rat foetus, in late pregnancy. The ACTH concentration decreases between 17 days 8 h and 17 days 15 h, then it increases regularly until the term. This evolution is correlated with the change in the fluorescence intensity of the corticotrophs and with the modification of the adrenocortical activity.     

Assessment of natural products in the Drosophila melanogaster BII cell bioassay for ecdysteroid agonist and antagonist activities

Ecdysteroid agonist and antagonist activities can be detected and quantified with the Drosophila melanogaster B(II) cell bioassay. This bioassay is convenient, sensitive and robust. We report the assessment with this bioassay of the activities of a wide range of compounds representing a number of classes of natural products. Many compounds were inactive over a wide concentration range (10(-8) to 10(-4) or 10(-3) M) or cytotoxic at high concentrations. However, antagonisitic activity was associated with several classes of compounds: cucurbitacins and withanolides (extending previous findings) and phenylalkanoids and certain alkaloids (described for the first time). A withanolide (withaperuvin D) is identified which possesses agonistic activity. Brassinosteroids, which have been ascribed (ant)agonistic properties in the past, were not found to be active in the B(II) bioassay, either as agonists or antagonists. Possible reasons for the prevalence of antagonists and for the low potency of the majority of them are discussed.     

Semi-synthesis and proposed structure of platelet-activating factor (P.A.F.): PAF-acether an alkyl ether analog of lysophosphatidylcholine]

We have studied the molecular structure of platelet-activating factor" (P.A.F.), a mediator of inflammation obtained from blood leukocytes, macrophages, and platelets themselves. We have semi-synthetized a substance that possesses all the known physicochemical and biological characteristics of P.A.F. from hog leukocytes. This was performed by successive methylation, hydrogenation, and acetylation of lysophosphatidylethanolamine plasmalogen. We therefore propose the following structure for P.A.F.: 1-0-alkyl-2-acetyl-glyceryl-3-phosphorylcholine. This molecular structure is not yet described among the numerous substances capable of inducing platelet aggregation and release.     

Prostacyclin-like activity of endothelium and subendothelium — important for atherosclerosis?

Summary Morphological control of Moncada's bioassay for prostacyclin (PG I₂) activity measurement shows that the activity depends not only on endothelium, but in important amounts on subendothelial tissue too. Therefore, it can be concluded that platelet thrombus formation after endothelial cell injury does not depend only on the PG I₂-producing ability of the tissue.     

Gonyauline: A novel endogenous substance shortening the period of the circadian clock of a unicellular alga

Summary The circadian clock in the unicellular algaGonyaulax polyedra is accelerated by a substance in extracts from the cells themselves. The extracts have been fractionated using the circadian rhythm of bioluminescence as bioassay. The active substance, termed gonyauline, has been isolated and characterized as a novel low molecular weight cyclopropanecarboxylic acid (S-methyl-cis-2-(methylthio) cyclopropanecarboxylic acid). Synthetic gonyauline has a similar shortening effect on the period of the circadian clock.