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.     

Prostaglandin-like substances in Propionibacterium acnes. III. Differential contractile effects on smooth muscle layers of the human utero-tubal junction.

The biological activity of a lipid fraction extracted from P. acnes was tested on isolated smooth muscle strips from the human utero-tubal junction. The bioassay experiments support the concept that prostaglandin-like substances (PLS) occur in P. acnes. However, in the bioassay system used, the effect of PLS was different from that of PGF2 alpha and PGI2 but similar, although not identical, to that of arachidonic acid and PGE2.     

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. 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. 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.     

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.     

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.     

Measurement of cyclic AMP in the islets of Langerhans of newborn rats. Effect of amino acids]

Radioimmunoassay of cyclic AMP (cAMP) in the islets of Langerhans from 48-64 h old Rats was performed after succinylation of the samples. cAMP was detected at 0.03 nM. The cAMP content of islets increases when L-arginine, L-lysine and L alanine are added together in the incubation medium at a concentration of 5-10 mM each. When phosphodiesterase is inhibited by theophylline the three amino acids considerably increase the cAMP content of islets. Thus an increase in cAMP content of the islets was observed with a concentration of amino acids which is efficient in stimulating the insulin and glucagon secretion.     

Hormonal control of mammalian oocyte meiosis at diplotene stage

Mammalian oocytes grow and undergo meiosis within ovarian follicles. Fully grown oocytes are arrested at the first meiotic prophase by a mural granulosa origin “arrester” until a surge of luteinizing hormone (LH) from the pituitary at the mid-cycle stimulates the immature oocyte to resume meiosis. Recent evidence indicates that natriuretic peptide precursor type C (NPPC) produced by mural granulosa cells stimulates the generation of cyclic guanosine 3′,5′-monophosphate (cGMP) by cumulus cell natriuretic peptide receptor 2 (NPR2), which diffuses into oocyte via gap junctions and inhibits oocyte phosphodiesterase 3A (PDE3A) activity and cyclic adenosine 3′,5′-monophosphate (cAMP) hydrolysis and maintains meiotic arrest with a high intraoocyte cAMP level. This cAMP is generated through the activity of the Gs G-protein by the G-protein-coupled receptor, GPR3 and GPR12, and adenylyl cyclases (ADCY) endogenous to the oocyte. Further studies suggest that endocrine hormones, such as follicle-stimulating hormone (FSH), LH, 17β-estradiol (E2) and oocyte-derived paracrine factors (ODPFs), participate in oocyte meiosis possibly by the regulation of NPPC and/or NPR2. A detailed investigation of NPPC and NPR2 expression in follicle cells will elucidate the precise molecular mechanisms of gonadotropins, and control the arrest as well as resumption of meiosis.     

Effect of dibutyryl cyclic AMP and analogs on the rate of contractions of myocytes in culture.

2O, 6N-butyryl, 3', 5'-cyclic monophosphate (dibu cAMP) when added to fetal rat heart cells in culture inhibits myocyte contraction. This inhibition is 100, 84 and 51% complete when the dibu cAMP concentration used is 2, 0.2 and 0.02 mM, respectively. The potency of dibu cAMP derivatives in myocyte contraction inhibition follows the order, dibu cAMP greater than 6N-bu cAMP greater than 2O-bu cAMP = AMP greater than butyrate. The inhibition caused by the first three chemicals is greater than 70%.     

Opposite effect of PGE2 on cAMP levels in human adrenal medulla and pheochromocytoma.

PGE2 (10(-7) M) caused increased cAMP accumlation in 5 pheochromocytomas, while in 3 human adrenal medullae PGE2 caused a significant decrease of cAMP level on incubating slices in vitro. This finding is discussed in relation to the opposite effect of PGE2 on catecholamine release from human medulla and pheochromocytoma slices in vitro.     

Modification of theophylline-induced lipolysis in human fat cells after trypsination.

Trypsin-treatment of human fat cells results in the potentiation of the lipolytic response and the cAMP accumulation induced by theophylline (5 . 10(-4) M) but not of those induced by theophylline (5 . 10(-3) M). The amount of cAMP formed after exposure to theophylline (5 . 10(-3) M) plus norepinephrine (5 . 10(-6) M) remains, however, 2.6 fold higher in trypsin-treated human fat cells than in the control ones.     

The brachymorphic mutation of mice and altered developmental patterns of limb bud 3':5' cyclic adenosine monophosphate

Concentrations of cyclic AMP (cAMP) were determined in paired fore and hind limbs from day 12-16 of development in murine fetuses homozygous for the brachymorphic (bm) mutation and normal controls. A developmental rise in cAMP occurred 1 day earlier in bm/bm than in +/+ hind limbs and cAMP was higher in day-13 bm/bm than in +/+ fore limbs. Since cAMP is well documented to stimulate chondrogenic differentiation, premature cartilage determination secondary to altered levels of cAMP could play a role in bm/bm short-limbed dwarfism.     

The role of cyclic adenosine monophosphate in the swarming phenomenon of Proteus mirabilis.

The levels of cylic AMP and adenyl cyclase in swarming and non-swarming cells of Proteus mirabilis and the effect of glucose on swarming have been investigated. The results indicate the cAMP is required for swarming, but that the flagellar derepression characteristic of swarming does not result from increased cAMP levels.     

The inhibitory effect of paraquat on histamine and isoproterenol induced changes of cyclic nucleotides in rat lung slices.

The incubation of rat lung slices with paraquat ion (10(-4) M) had no effect on cAMP and cGMP levels of the rat lung slices. The preincubation with the same concentration of paraquat inhibited the cAMP elevating effect of histamine (10(-5) M) and isoproterenol (10(-5) M) and reduced the cGMP level to approximately 50% of the level obtained without preincubation with paraquat.     

The brachymorphic mutation of mice and altered developmental patterns of limb bud 3′∶5′ cyclic adenosine monosphosphate

Summary Concentrations of cyclic AMP (cAMP) were determined in paired fore and hind limbs from day 12–16 of development in murine fetuses homozygous for the brachymorphic (bm) mutation and normal controls. A developmental rise in cAMP occurred 1 day earlier inbm/bm than in +/+ hind limbs and cAMP was higher in day-13bm/bm than in +/+ fore limbs. Since cAMP is well documented to stimulate chondrogenic differentiation, premature cartilage determination secondary to altered levels of cAMP could play a role inbm/bm short-limbed dwarfism.This work was supported by a grant from the National Foundation-March of Dimes.     

Correlation of immunogenicity with suppression of lymphocyte adenosine 3',5'-monophosphate-dependent protein kinase.

Cyclic-AMP-dependent protein kinase activity was depressed in whole spleen as well as in isolated splenic lymphocytes from 3-methylcholanthrene (MCA), R3230 AdCa mammary adenocarcinoma, N-hydroxy-2-acetylaminofluorene, and 4-dimethylaminoazobenzene (DMAAB) tumor-bearing Fischer rats as compared to control animals. The magnitude of depression increased with the immunogenicity of the tumor. The depressed enzyme activity was the result of a reduced Vmax for adenosine 3',5'-monophosphate (cAMP)-stimulated histone phosphorylation.     

Selection of cell lines resistant to cyclic AMP and theophylline from murine plasmocytoma MOPC 173. Cross resistance to ouabain and concanavalin A]

Using cAMP or theophyllin as selective agents, we obtained from contact inhibited and non contact inhibited cell lines, derived from the same plasmocytoma, different resistant cell lines. All of them were cAMP and theophyllin resistant and also ouabain and con A resistant as judged by the growth curves in presence of the different drugs.     

alpha-globulin follicular fluid proteins within small and large bovine follicles.

Fluids from small (FF-S) and large (FF-L) bovine ovarian follicles were observed electrophoretically for differences in the alpha-globulin protein profile. FF-L possessed a fast migrating alpha-globulin 3 and a greater percentage of FF-L samples contained a higher number of alpha-globulin bands.     

Lipid accumulation by a cellulolytic strain of Aspergillus niger.

Lipid accumulation by a cellulolytic mold, Aspergillus niger, was studied. The amount of lipid accumulated ranged from 13.6-16.6% on various carbon sources, namely glucose, xylose, avicel (microcrystalline cellulose) and bagasse (a natural lignocellulosic substrate). Neutral lipids, phospholipids and glycolipids of the mycelia varied from 41.0-46.2%, 34.9-38.4% and 18.7-22.6% of total lipids, respectively. Unsaturated fatty acids comprised around 80% of total fatty materials with linoleic and oleic acid predominating. Of the four nitrogen sources tested, NH4Cl was the best source for lipid synthesis from cellulose (bagasse). Optimum temperature range for growth and lipid synthesis was 25-30 degrees C.