Interaction between an organic hydroperoxide and an unsaturated phospholipid and alpha-tocopherol in model membranes

The behavior of an organic hydroperoxide in the presence of lipid and/or alpha-tocopherol in model membranes has been studied using 14C-labeled cholesterol-5 alpha-hydroperoxide as the organic hydroperoxide. Cholesterol-F alpha-hydroperoxide in saturated phospholipid micelles is rapidly isomerized to cholesterol-7 alpha-hydroperoxide. Such an isomerization is inhibited by alpha-tocopherol, but not by an alpha-tocopheryl analogue with a substituted OH groups, present in the micelles, indicating the formation of hydrogen bonds between OH group in alpha-tocopherol and OOH group in the 5 alpha-hydroperoxide. The double bonds in unsaturated phospholipid can also serve to form a hydrogen bond with OOH in the 5 alpha-hydroperoxide moiety in the micelles. The resulting hydrogen-bonded complex could be decomposed by iron-induced lipid peroxidation, accompanied by isomerization of the 5 alpha-hydroperoxide and the further degradation to the 7-ketocholesterol and 7 alpha-hydroxycholesterol. When three components, such as unsaturated phospholipid, 5 alpha-hydroperoxide and alpha-tocopherol, are present in the same micelles, they form hydrogen bonded complexes. Such complexes could be decomposed by iron in the ferrous state, yielding mainly 5 alpha-hydroxycholesterol without significant change in the structure of alpha-tocopherol and peroxidative cleavage of unsaturated phospholipid.

Effect of adenosine-5'-triphosphate-3'-diphosphate and related nucleoside polyphosphates on the spore germination of Streptomyces galilaeus

Exogenous addition of adenosine- and guanosine 5'-(di- and tri) phosphate 3'-diphosphate (pppApp, ppApp, pppGpp and ppGpp) at the concentration of 0.5 mM inhibits spore germination of Streptomyces galilaeus ATCC 31133. This reversible inhibitory effect appeared to be at the transcriptional level, and also depends on the phase of spore germination; pppApp inhibited more strongly RNA synthesis in the period of the germ tube emergence than the early stage of germination. No inhibitory effect was observed with normal purine and pyrimidine nucleosides, nucleotides, pApp, pGpp, cyclic AMP and pyrophosphoric acid at the concentration of 0.1 - 1.0 mM.

[Studies on the stability of aclacinomycin hydrochloride. I. Stability of solution of aclacinomycin hydrochloride (author's transl)]

Aclacinomycin is an antitumor anthracycline antibiotic isolated from the culture broth of Streptomyces galilaeus MA144-M1. In this study, the effects of heat, light and pH on the aqueous solution of aclacinomycin hydrochloride (ACM-HCl) were investigated. The following results were found: (1) The kinetic studies revealed that the thermal inactivation of ACM-HCl solution (pH 4.5) was based on the apparent first-order reaction and that Arrhenius equation was confirmed to be established between the rate constants and temperatures. When ACM-HCl solution was stored at 20, 10 and 5 degrees C, the estimated term of ACM-HCl solution at the time when the initial activity (100%) reduced to 90% residual concentration was 1.5, 6 and 12 months, respectively. (2) It was clarified by pH-log k profile that ACM-HCl solution was most stable near at pH 4.5. (3) The higher the buffer concentration was used, the faster the degradation rate, but there was no difference between the residual activity ratios at the various concentrations of ACM-HCl solution. (4) The inactivation of ACM-HCl solution under sunlight occurred in a type of zero-order reaction so that the faster inactivation rates were obtained at the more diluted concentration of ACM-HCl. (5) The major degradation products of ACM-HCl solution were 1-deoxypyrromycin (DP), MA144 S1 (S1) and bisanhydroaklavinone (F1). DP and S1 were mainly found at pH below 4.0 and F1 at pH above 5.0. The degradation under sunlight gave L1 (N-monodemethyl ACM) accompanied by the degradation of aglycone moiety in part.

[Studies on the absorption, excretion and distribution of aclacinomycin A: absorption, excretion and distribution of aclacinomycin A in mice, rabbits and dogs by photometric assay (author's transl)]

An anthracycline antitumor antibiotic, aclacinomycin A, was given to mice, rabbits or dogs intravenously to study the pharmacokinetics by photometric assay based on the absorption of anthracycline ring. The drug was rapidly eliminated from the blood in these animals. Drug levels were much higher in the blood cells than in the plasma. Tissue levels in dogs were 50 approximately 100 times higher than the blood levels, which showed the drug was rapidly transferred from the blood to tissues after administration. Higher levels were observed in the lungs, spleen and lymph nodes, where the drug was present as aclacinomycin A itself and the glycoside-type metabolites that were biologically active. The active form was also detected in the pancreas, heart, thymus, bone marrow and gastrointestinal tract. In the liver and kidneys, biologically inactive aglycone-type metabolites were observed. About 2 approximately 4% of the drug given to rabbits or dogs was recovered in the urine by 72 hours after administration, in which only 10% of the excreted drug was active form in rabbits but about 65% in dogs. The rest was inactive aglycone-type metabolites that were excreted almost in the conjugated form. Biliary excretion also contributed to the total clearance of the drug. Aclacinomycin A was absorbed even by oral administration in rabbits and dogs. Tissue distribution of the drug orally given to dogs was similar to that in intravenous administration, except that higher levels of active form were detected in the gastrointestinal tract and of inactive form in the liver.

[Studies on the absorption, excretion and distribution of aclacinomycin A: absorption, excretion and distribution of 14C- or 3H-aclacinomycin A in mice, rats and rabbits (author's transl)]

A new anthracycline antitumor antibiotic, aclacinomycin A, was labeled with 3H uniformly or with 14C simultaneously at the anthracycline nucleus and L-rhodosamine. These labeled drugs were administered intravenously to normal dd mice, solid type Sarcoma 180 tumor-bearing ICR mice, normal or pregnant Wistar rats and normal rabbits, respectively. 14C-Aclacinomycin A given to rabbits (5 mg/kg) was rapidly cleared from the blood and transferred to tissues. But low level of radioactivity (equivalent to about 0.5 mcg/ml) was remained in the blood even 8 approximately 10 hours after administration. About 45% of the radioactivity were recovered from the urine and 20% from the feces by 72 hours after administration. Tissue levels of 3H-14C-aclacinomycin A given to normal and tumor-bearing mice were highest in the lungs and spleen. Higher distribution was observed also in the liver and kidneys 2 hours after administration. Bioassay revealed that the drug was present in the lungs and spleen in biologically active form and in the liver and kidneys in inactive form, respectively. In the tumor tissue the radioactivity was low but it persisted for 48 hours. Autoradiography with 14C-aclacinomycin A in rats demonstrated that radioactivity due to the drug distributed in the lungs, spleen, kidneys, thymus, intestine, lymph nodes, bone marrow, salivary gland, hypophysis and pineal body but it was rapidly cleared. About 0.2% of radioactivity given to a pregnant rat were transferred to a fetus when 14C-aclacinomycin A was administered intravenously on the 18 approximately 19th day of pregnancy.

Current status of Japanese studies with the new anthracycline antibiotic aclacinomycin A

Fundamental and clinical studies on a new yellow anthracycline antibiotic aclacinomycin A are reviewed. Favorable responses were seen in patients with acute leukemia refractory to daunomycin and adriamycin, malignant lymphoma, and breast, ovarian, lung, gastric, intestinal, and urinary bladder cancers by intravenous and intraperitoneal infusions or bladder instillation of aclacinomycin A alone in the phase II study.

Ultrastructure of cartilage in heritable disorders of connective tissue

Ultrastruct of cartilage were examined in Marfan syndrome, Menkes kinky hair syndrome, achondroplasia, asphyxiating thoracic dysplasia, mild diastrophic dysplasia and mucopolysaccharidoses I and III. Ruthenium red staining revealed decrease of proteoglycans in cases with Marfan syndrome and kinky hair syndrome, and increase in cases with osteochondrodysplasia and mucopolysaccharidosis III. This morphologic tendency coincided with the result obtained by biochemical analysis of glycosaminoglycan contents in cartilage matrix from cases with Marfan syndrome (decreased content) and asphyxiating thoracic dysplasia (increased content). It was postulated that proteoglycan content in cartilage matrix might be related to excessive or reduced skeletal growth in Marfan syndrome or osteochondrodysplasia.

Antitumor anthracycline antibiotics, aclacinomycin A and analogues. I. Taxonomy, production, isolation and physicochemical properties

Aclacinomycin A and B, two major components of a new antitumor antibiotic complex, and their 19 analogues were produced by a culture of strain No. MA144-M1, which was identified as Streptomyces galilaeus. They were isolated by chelation with copper ion and silicic acid chromatography, and characterized by physicochemical methods in the anthracycline group of antibiotics.

Reduction of cinerulose in aclacinomycin-A by soluble and microsomal cinerulose reductases

The in vitro metabolism of the antitumor anthracycline antibiotic, aclacinomycin-A, was studied using rat liver homogenate. In the presence of NADH or NADPH, aclacinomycin-A was converted to aclacinomycin-A analogs, MA144 M1 and MA144 N1, which were stereospecifically reduced at the keto group of the C-4''' position of L-cinerulose in aclacinomycin-A. Subcellular fractionation indicated that the production of MA144 M1, which was reduced to L-amicetose, was catalyzed by NADPH-dependent soluble cinerulose reductase I, and the production of MA144 N1, which was reduced to L-rhodinose, was catalyzed by NADPH-dependent soluble cinerulose reductase II and NADH-dependent microsomal cinerulose reductase. The properties of these three enzymes were studied. Soluble cinerulose reductase I which produces MA144 M1 showed a optimum pH at 6.3, Km values of 3.3 x 10(-4) M for aclacinomycin-A and 3.2 x 10(-5) M for NADPH. Soluble cinerulose reductase II which produces MA144 N1 showed a pH optimum at 6.3 and Km values of 2.0 x 10(-3) M for aclacinomycin-A and 4.0 x 10(-5) M for NADPH. All thesse reductases were sensitive to sulfhydryl reagents and were inhibited by vitamin K3. Microsomal cinerulose reductase showed sensitivity to diconmarol and ferrous ion. The main nondegradative pathways of aclacinomycin-A were discussed from these results.

Enzymatic conversion of aclacinomycin A to Y by a specific oxidoreductase in Streptomyces

A specific oxidoreductase converting aclacinomycin A to a new analog, aclacinomycin Y, was purified to apparent homogeneity from the culture filtrate of aclacinomycin-producing microorganisms. The isolated enzyme was a weakly acidic protein (isoelectric point, 5.9) with a molecular weight of about 72,000. The enzymatic reaction requires molecular oxygen and has a pH optimum at 5.5. The enzyme catalyzed an oxidation of the terminal sugar, L-cinerulose, of the trisaccharide moiety of aclacinomycin A to L-aculose (2,3,6-trideoxyhex-2-enopyranos-4-ulose) with removal of two electrons. Studies of substrate specificity revealed that the enzyme is an oxidoreductase capable of modifying anthracyclic triglycosides by oxidizing their terminal sugars.

Effect of guanosine 5'-diphosphate 3'-diphosphate and related nucleoside polyphosphates on induction of tryptophanase and beta-galactosidase in permeabilized cells of Escherichia coli

Exogenous addition of guanosine and adenosine 5'-(mono, di and tri) phosphate 3'-diphosphates (pppGpp, ppGpp, pGpp, pppApp, ppApp and pApp) stimulated the synthesis of tryptophanase and beta-galactosidase in permeabilized cells of Escherichia coli. From the results obtained with ppGpp and pppApp, this effect appeared to be at a transcriptional level and depended greatly on the growth condition; the largest effect was observed in cells under shiftdown or grown on poor enrgy source. ppGpp and pppApp, unlike cyclic AMP, did not act to overcome the inhibition of enzyme induction by glucose, but in combination with cyclic AMP caused a synergistic stimulation effect. In the shiftdown cells, ppGpp and pppApp gave 30% or more stimulation effect on tryptophanase induction while cyclic AMP did not stimulate induction. There was therefore a pronounced difference between cyclic AMP and ppGpp or pppApp in stimulatory function.

New anthracycline antibiotics

A number of anthracycline antibiotics have been found in Streptomyces cultures. Among them, adriamycin and daunomycin have been studied most in detail, because these compounds have exhibited a strong antitumor activities 1, 2). However, their clinical usefuleness is limited by side effects, particularly by bone marrow suppression and cumulative dose-dependent cardiac toxicity. 3 approximately 5) By the collaboration with Prof. H. UMEZAWA and Dr. T. TAKEUCHI, Institute of Microbial Chemistry, for the studies to find out new anthracycline antibiotics that may have lower cardiac toxicity and the same degree of the antitumor activity, we found 32 new anthracycline compounds in Streptomyces cultures and aclacinomycin A is under the phase II clinical study. Anthracycline compounds can be classified depending on the structures of their aglycones as shown in Table 1. These compounds have a linear tetracyclic polyhydroxy anthracyclines, and can be grouped into seven groups. Biologically active anthracycline antibiotics have various sugar moieties at C-7 and/or C-10 position of the anthracyclinones. In 1951, H. BROCKMANN6) discovered rhodomycins A and B in the culture of a new species of Streptomyces purpurascens. Since then, he found numerous anthracycline compounds such as rhodomycin-, isorhodomycin- and pyrromycin-types in Streptomyces and elucidated their structures. All of these anthracyclines are red pigments. In 1964 and 1969 new group of orange-red anthracycline antibiotics: daunomycin10) and adriamycin11) was reported by DiMARCO and F. ARCAMONE. Moreover, aklavin12, 13) which has yellow aklavinone as aglycone and citromycinone aglycone14) which is also yellow have been isolated in the Streptomyces cultures. Aclacinomycin A15), which we found in Streptomyces galilaeus MA144-M1, has aklavinone aglycone and is becoming more interesting in its low cardiac toxicity.

Antitumor activity of new anthracycline antibiotics, aclacinomycin-A and its analogs, and their toxicity

New anthracycline antibiotics have been isolated from the culture of Streptomyces galilaeus MA144-M1. Among 14 anthracycline compounds, aclacinomycin-A showed the strongest activity in inhibiting leukemia L-1210 and had lower toxicity than others. Antitumor activity of aclacinomycin-A against leukemia L-1210 and P-388, solid sarcoma-180, and lymphosarcoma 6C3HED was examined in comparison with adriamycin and daunomycin. Aclacinomycin-A showed the same degree of activity against leukemia L-1210 and P-388, when administered intraperitoneally, as daunomycin and somewhat less than adriamycin. In oral administration, aclacinomycin-A also exhibited a significant activity on leukemia L-1210. The degree of inhibition of the growth of sarcoma-180 and 6C3HED lymphosarcoma transplanted subcutaneously by aclacinomycin-A was almost the same as that of adriamycin and daunomycin, although the optimal dose was about twice more than adriamycin. Acute cardiotoxicity of aclacinomycin-A by a test using hamsters was more than 10 times lower than that of adriamycin.

Clinical features and treatment of joint dislocations in Larsen's syndrome. Report of three cases in one family

Of 3 cases of Larsen's syndrome in one family, one had bilateral dislocation of the hip and the knee joints. The knee joint was not reduced by manipulation and corrective cast, while both hip and knee joints were simultaneously reduced by skeletal traction of the tibia at the age of 4 months, and the course was satisfactory. Reduction of joint dislocations should be attempted by a conservative method such as skeletal traction as early as possible. Various radiographic skeletal abnormalities occurred in all 3 cases. Larsen's syndrome very likely has a genetic origin.

The application of phenoxybenzamine in open heart surgery using cardiopulmonary bypass

The effects of vasodilator therapy upon organ blood flow, beta-glucuronidase activity in plasma and pulmonary surfactant were evaluated before and during cardiopulmonary bypass. Alpha adrenergic blockade with phenoxybenzamine increased the organ blood flow in the heart, brain, stomach, small intestine, large intestine, and liver, whereas it decreased the organ blood flow in the kidney, spleen, and lung. These changes were extremely similar to those observed at hemorrhagic shock. With 2 mg/kg of POB the organ blood flow tended to approach to control levels. The increase of beta-glucuronidase activity at hemorrhagic shock was considerably inhibited after intravenous drip of 2 mg/kg of phenoxybenzamine. We examined the changes of pulmonary surfactant biochemically. Pulmonary surfactant was decreased in endotoxin shock and similar changes were observed in cardiopulmonary bypass when perfusion time was extended to 3 hours. The decrease of pulmonary surfactant after bypass was inhibited by application of POB. From these results, we supposed that the circulatory dynamics during cardiopulmonary bypass might be similar to that of shock and the application of POB in cardiopulmonary bypass might be useful. We applied POB clinically and had good results.

Occurrence of pppApp-synthesizing activity in actinomycetes and isolation of purine nucleotide pyrophosphotransferase

The occurrence of adenosine 5'-triphosphate-3'diphosphate-synthesizing activity was detected in five strains of actinomycetes; Streptomyces morookaensis, Streptomyces aspergilloides, Streptomyces hachijoensis, tactinomyces violascens and Streptoverticillium septatum, out of 825 strains of actinomycetes, bacteria, fungi and fungi imperficti. Purine nucleotide pyrophosphotransferase were extracellularly excreted associating with the cell growth, and were purified partially or to apparent homogeneiety from the culture filtrate. The enzymes are a monomeric protein with molecular weight of 18,000-26,000 and synthesize adenosine, guanosine and inosine 5'-phosphate (mono, di or tri)-3'-diphosphate such as pApp, ppA pp, pppApp, pGpp, ppGpp, pppGpp, and pppIpp by transferring a pyrophosphoryl group from the 5'-position of ATP, dATP and ppApp to the 3'-position of purine nucleotides in the presence of a divalent cation and in alkaline state.

Purine nucleotide pyrophosphotransferase from Streptomyces morookaensis, capable of synthesizing pppApp and pppGpp

Purine nucleotide pyrophosphotransferase was purified to apparent homogeneity from a culture filtrate of Streptomyces morookaensis. It is a monomeric protein with a molecular weight of 24 000-25 000, and its isoelectric point is 6.9. The enzyme synthesizes purine nucleoside 5'-phosphate (mono, di, or tri) 3'-diphosphates such as pppApp, ppApp, pApp, pppGpp, ppGpp and pppIpp by transferring a pyrophosphoryl group from the 5'-position of ATP, dATP and ppApp to the 3'-position of purine nucleotides. The purified enzyme catalysed the formation of 435 mumol of pppApp and 620 mumol of pppGpp from ATP and GTP per min mg protein under the standard conditions. The enzyme requires absolutely a divalent cation for activity, and optimum pH for the enzyme activity lay above 10 for Mg2+, for Co2+ and Zn2+ from 9 to 9.5, and for Fe2+ from 7.5 to 8. The following Michaelis constants were determined: AMP, 2.78 mM; ADP, 3.23 mM; GMP, 0.89 mM; GDP, 0.46 mM and GTP, 1.54 mM, in the case of ATP donor. The enzyme is inhibited by guanine, guanosine, dGDP, dGTP, N-bromosuccinimide, iodacetate, sodium borate and mercuric acetate.

Anterior mitral valve echo in patients with isolated ventricular septal defect and with tetralogy of Fallot

Eight patients with isolated ventricular septal defect and two patients with tetralogy of Fallot were studied by UCG. Two of these patients showed notchings and five showed flutterings on F-A portions of the anterior mitral leaflet echoes. Fluttering seemed to be recorded more frequently in patients with right-to-left shunts such as cyanotic tetralogy of Fallot. It was considered that these functional changes of mitral valve echoes during diastole would be caused by the direction and amounts of blood flow across the defect and the velocity and amounts of blood flow through the mitral valve. Fluttering of mitral valve echo during diastole may be observed in normal subjects or in patients with other cardiac abnormalities, such as aortic insufficiency, atrial fibrillation or flutter. Flutterings seen in ventricular septal defect and tetralogy of Fallot are, however, of low amplitudes and of high frequencies, and are observed mainly between F and A points.

Deoxyribonucleic acid bacteriophage of methanomonas methylovora

A new bacteriophage of low guanine plus cytosine (GC) content for Methanomonas methylovora has been isolated. Phage deoxyribonucleic acid contained 32 to 35% GC.