Formation and stability of the dispersed particles composed of retinyl palmitate and phosphatidylcholine

The purpose of this study was to develop an intravenous formulation composed of retinyl palmitate (RP) for the treatment of cancer. RP was dispersed with soybean phosphatidylcholine (PC) using sonication and the dispersal mechanism was evaluated by characterizing the dispersed particles using dynamic light-scattering, fluorescence spectroscopy, and surface monolayer techniques. The dispersions in the RP mole fraction range of 0.1-0.8 were stable at room temperature for 3 days. A limited amount of RP was incorporated into PC bilayer membranes (approximately 3 mol%). The excess RP separated from the PC bilayers was stabilized as emulsion particles by the PC surface monolayer. When the PC content was less than the solubility in RP, the PC monolayer did not completely cover the hydrophobic RP particle surfaces and separation into oil/water occurred. The miscibility between RP and PC and the lipid composition were critically important for the stability of the dispersed particles (coexistence of emulsion particles [surface monolayer of PC + core of RP] with vesicular particles [bilayer]) of the lipid mixtures.

Prevention of endotoxin-induced lethality in mice by calmodulin kinase activator

Porphyromonas gingivalis strain 381 lipid A showed lower activity in inducing interleukin (IL)-1alpha and IL-1beta production and cytokine mRNA expression than synthetic Escherichia coli lipid A (compound 506) in alveolar macrophages of C57BL/6 mice. Both the lipid As induced tumor necrosis factor alpha in alveolar macrophages and IL-6 in peritoneal macrophages. A calmodulin (CaM) antagonist, W-7, inhibited IL-1beta production and its mRNA expression induced by P. gingivalis lipid A but not compound 506 in alveolar macrophages. A CaM kinase activator reduced the induction of IL-1beta in the serum of mice when administered with compound 506, and protected the mice against the lethal toxicity. The modulation of a variety of intracellular enzymes including the CaM kinase may result in clinical control of endotoxic sepsis.

Dehydroepiandrosterone retards atherosclerosis formation through its conversion to estrogen: the possible role of nitric oxide

Dehydroepiandrosterone (DHEA) is speculated to have an antiatherosclerotic effect, although the mechanism of action remains unclear. The objective of the current study was to determine whether the antiatherosclerotic effect of DHEA is related to its conversion to estrogen and to define the role of nitric oxide (NO) in the antiatherosclerotic effect of DHEA. Forty-eight oophorectomized rabbits were divided into 5 groups and fed the following diets for 10 weeks: group 1, a regular rabbit diet plus 1% cholesterol (a high-cholesterol diet [HCD]); group 2, an HCD plus 0.3% DHEA; group 3, an HCD plus 0.3% DHEA and fadrozole (2.0 mg x kg(-1) x d(-1)), a specific aromatase inhibitor; group 4, an HCD plus 17beta-estradiol (20 microg x kg(-1) x d(-1)); and group 5, a regular diet. Atherosclerotic lesions, lipid deposition in aortic vessels, and basal and stimulated NO release were measured in the aforementioned groups of rabbits. NO release was measured by using an NO-selective electrode as well as by measuring vascular responses and the plasma NO metabolites nitrite and nitrate. The plasma total cholesterol level was increased, but there were no significant differences in lipid profile in the 4 groups of rabbits that were fed the HCD. The area occupied by atherosclerosis in the thoracic aorta was diminished by approximately 60% in the DHEA-treated rabbits (group 2) compared with the HCD group of rabbits (group 1); there was a corresponding 80% decrease in the estradiol group (group 4) but only a 30% decrease in the DHEA plus fadrozole group (group 3). In the aortas of rabbits from groups 1 and 3, the acetylcholine-induced and tone-related basal NO-mediated relaxations were diminished compared with those of the controls (group 5). However, these relaxations were restored in the aortas of group 2 and 4 rabbits, and an increase in NO release was observed in groups 2 and 4 compared with groups 1 and 3, as measured by an NO-selective electrode. Injection of neither solvent (20% ethanol/distilled water) nor fadrozole significantly affected the atherosclerotic area or the NO-related responses described above. We conclude that approximately 50% of the total antiatherosclerotic effect of DHEA was achieved through the conversion of DHEA to estrogen. NO may also play a role in the antiatherosclerotic effect of DHEA and 17beta-estradiol.

Grepafloxacin inhibits tumor necrosis factor-alpha-induced interleukin-8 expression in human airway epithelial cells

We examined the effect of grepafloxacin (GPFX), a new fluoroquinolone antimicrobial agent, on interleukin-8 (IL-8) expression in tumor necrosis factor-alpha (TNF-alpha)-stimulated human airway epithelial cells (AEC). GPFX inhibited IL-8 protein production as well as mRNA expression in a concentration-dependent manner (2.5 - 25 micro g/ml), but the inhibition of IL-8 expression by corresponding concentrations of GPFX to serum and airway lining fluids was not complete. We discuss the modulatory effect of GPFX on IL-8 production in the context of its efficacy on controlling chronic airway inflammatory diseases.

[A case of teratoma in both the mediastinum and the intrapulmonary system]

A rare case of mature teratoma in both the mediastinum and the intrapulmonary system is presented. A 30-year-old male was admitted to our hospital due to tumor masses in the mediastinum and the left lung. We performed mediastinal tumor resection and left upper partial lobectomy. Neither tumor communicated with each other. Pathological findings revealed teratoma in the mediastinal lymph node and the intrapulmonary system including no malignant cells in either tumor. In this case, because metastasis and perforation were negative, we proposed that both tumors occurred at the same time in the early embryo.

Comparison of the effect of lipid A analog E5531 and the lipid A from Escherichia coli on phospholipid membrane properties

The effect of the lipid A analog E5531 on the phospholipid membrane was compared with that of the lipid A from Escherichia coli (EC). E5531 decreased the phase transition temperature of dipalmitoylphosphatidylcholine (DPPC) membrane and increased the fluidity and micropolarity. On the other hand, the effect of EC on the membrane was contradictory. These results suggested that the reason for the difference of biological effects of these two lipid A would be caused by the differences from the effect on the cell membranes.

Cysteine-scanning mutagenesis of the periplasmic loop regions of PomA, a putative channel component of the sodium-driven flagellar motor in Vibrio alginolyticus

The sodium-driven motor consists of the products of at least four genes, pomA, pomB, motX, and motY, in Vibrio alginolyticus. PomA and PomB, which are homologous to the MotA and MotB components of proton-driven motors, have four transmembrane segments and one transmembrane segment, respectively, and are thought to form an ion channel. In PomA, two periplasmic loops were predicted at positions 21 to 36 between membrane segments 1 and 2 (loop(1-2)) and at positions 167 to 180 between membrane segments 3 and 4 (loop(3-4)). To characterize the two periplasmic loop regions, which may have a role as an ion entrance for the channel, we carried out cysteine-scanning mutagenesis. The T186 residue in the fourth transmembrane segment and the D71, D148, and D202 residues in the predicted cytoplasmic portion of PomA were also replaced with Cys. Only two mutations, M179C and T186C, conferred a nonmotile phenotype. Many mutations in the periplasmic loops and all of the cytoplasmic mutations did not abolish motility, though the five successive substitutions from M169C to K173C of loop(3-4) impaired motility. In some mutants that retained substantial motility, motility was inhibited by the thiol-modifying reagents dithionitrobenzoic acid and N-ethylmaleimide. The profiles of inhibition by the reagents were consistent with the membrane topology predicted from the hydrophobicity profiles. Furthermore, from the profiles of labeling by biotin maleimide, we predicted more directly the membrane topology of loop(3-4). None of the loop(1-2) residues were labeled, suggesting that the environments around the two loops are very different. A few of the mutations were characterized further. The structure and function of the loop regions are discussed.

Formation and stability of the dispersed particles composed of retinoic acid, sesame oil and phosphatidylcholine

All trans-retinoic acid (RA) was dispersed by sonication with soybean phosphatidylcholine (PC). The particle size in the dispersion was increased to 240 nm up to the RA mol fraction range (X(RA)) of 0.4. At X(RA)=0.5, the RA/PC mixture was difficult to disperse and the macroscopic oil/water phase separation was observed. On the other hand, by the addition of sesame oil (SO) to RA (molar ratio of RA:SO=1:1), stable aqueous dispersions (diameter: 40-80 nm) were obtained in the mol fraction range RA and SO mixture (X(M)) of 0.1-0.8. In order to clarify these dispersal mechanism, the dispersed particles were characterized and the interaction among RA, SO and PC was investigated using several physicochemical techniques. The trapped aqueous volume inside the RA/PC particles was determined using the aqueous space marker, calcein and it was increased with the addition of RA into small unilamellar vesicles of PC. On the other hand, that of RA/SO/PC particles was decreased remarkably with increase in X(M) and the decline in the fraction of vesicular particles was also confirmed by fluorescence quenching of N-dansylhexadecylamine in the PC membrane by the addition of the quencher CuSO(4). These results indicate that the interaction of RA with PC bilayers and the structure of RA/PC mixture will be changed by the addition of SO.

Interaction of ubiquinone-10 with dipalmitoylphosphatidylcholine and their formation of small dispersed particles

Stable aqueous dispersions of ubiquinone-10 (UQ) were obtained by cosonication with dipalmitoylphosphatidylcholine (DPPC) in the UQ mole fraction range 0.1-0.7. To clarify the dispersal mechanism, the dispersed particles were characterized, and the interaction between UQ and DPPC was investigated using several physicochemical techniques. Dynamic light scattering (DLS) measurements showed that the diameter of the dispersed particles was 50-70 nm. A limited amount of UQ was incorporated into DPPC bilayer membranes (approximately 5 mol%). The trapped aqueous volume inside the particles was determined fluorometrically using the aqueous space marker calcein, and the volume in the UQ/DPPC particles decreased remarkably with the addition of UQ into small unilamellar vesicles of DPPC. The decline in the fraction of vesicular particles was also confirmed by fluorescence quenching of N-dansylhexadecylamine in the DPPC membrane by the addition of the quencher CuSO4. These results indicate that the excess UQ separated from the DPPC bilayers is stabilized as emulsion particles by the DPPC surface monolayer.

The effect of divalent cations on the membrane properties and pharmacokinetics in rat of the lipid A analogue E5531

To obtain information on the effects of Ca2+ on the membrane properties of the lipid A analogue E5531, we have determined the aggregate size, zeta potential, membrane fluidity, micropolarity and permeability of the E5531 membrane as a function of Ca2+ levels. Within the molar ratios of [Ca2+]/[E5531] = 1 and 3, Ca2+ increased the zeta potential of the E5531 membrane but had no effect on aggregate size (approximately 20 nm). Within the above ratios, Ca2+ decreased the membrane fluidity, as measured by micropolarity of E5531 and increased the phase transition temperature. The pharmacokinetics in rats for these samples with different membrane fluidity, prepared by changing the pre-dose formulation concentration of Ca2+, was determined and a correlation between membrane fluidity and pharmacokinetics was clearly observed. It thus appears that Ca2+ effects the membrane fluidity of E5531 as well as its pharmacokinetics in rats.

Endothelium-dependent relaxation of rabbit atherosclerotic aorta was not restored by control of hyperlipidemia: the possible role of peroxynitrite (ONOO(-))

We determined the role of ONOO(-) in nitric oxide (NO) mediated vascular response in atherosclerosis and regression following removal of dietary cholesterol. The effect of ONOO(-) on NO-mediated vascular responses was examined in vitro. Basal and stimulated NO release was estimated by an NO-selective electrode as well as vascular response and the plasma NO metabolites. An immunohistochemical study was also carried out. Responses were compared in normal controls, atherosclerotic rabbits fed 1% cholesterol diet for 6 or 9 weeks (atherosclerotic group) and animals fed a normal diet for 6-36 weeks after the high cholesterol diet for 6 or 9 weeks (regression group). ONOO(-) impaired the basal and acetylcholine-stimulated NO release, but did not affect endothelium-independent relaxation. After 15 weeks on a normal diet, the acetylcholine-stimulated and basal NO-mediated relaxation, which was diminished in the aorta induced by 6 weeks high cholesterol diet, became restored. However, the vascular response in the 9 weeks high cholesterol diet group did not return to normal after 36 weeks on a normal diet. iNOS was observed in atherosclerotic plaques in atherosclerotic and regression groups along with ONOO(-) in the 9 weeks high cholesterol diet group, but not in the 6 weeks group. Conclusively, ONOO(-) can play a role in impairment of NO-mediated vascular response during the regression of dietary cholesterol-induced atherosclerosis, not in the initiation of atherosclerosis.

TMC-171A,B,C and TMC-154, novel polyketide antibiotics produced by Gliocladium sp. TC 1304 and TC 1282

Four new antibiotics, TMC-171A (2), B (3), C (4) and TMC-154 (5) have been isolated from the fermentation of fungal strains Gliocladium sp. TC 1304 and TC 1282, respectively. Spectroscopic and degradation studies have shown that TMC-171s and TMC-154 were new members of the TMC-151 class of antibiotics, unique polyketides modified with a D-mannose and a D-mannitol or a D-arabitol. These compounds showed moderate cytotoxicity to various tumor cell lines.

p38 MAP kinase regulates RANTES production by TNF-alpha-stimulated human pulmonary vascular endothelial cells

BACKGROUND

RANTES plays an important role in the production of allergic inflammation of the airway through its chemotactic activity for eosinophils. However, the intracellular signal regulating RANTES expression in human pulmonary vascular endothelial cells has not been determined. In the present study, therefore, we examined the role of p38 mitogen-activated protein (MAP) kinase in RANTES production by tumor necrosis factor (TNF)-alpha-stimulated pulmonary vascular endothelial cells in order to clarify the signal transduction pathway regulating RANTES production by pulmonary vascular endothelial cells.

METHODS

We examined p38 MAP kinase activation, and the effect of SB 203580, as the specific inhibitor for p38 MAP kinase, on p38 MAP kinase activity and RANTES production by TNF-alpha-stimulated human pulmonary vascular endothelial cells.

RESULTS

The results showed that TNF-alpha induced RANTES production and p38 MAP kinase activity in human pulmonary vascular endothelial cells. Abrogation of p38 MAP kinase activity by SB 203580 repressed TNF-alpha-induced p38 MAP kinase activity and RANTES production.

CONCLUSIONS

These results indicate that p38 MAP kinase plays an important role in the TNF-alpha-activated signaling pathway which regulates RANTES production by human pulmonary vascular endothelial cells.

Interaction of sesame oil with soybean phosphatidylcholine and their formation of small dispersed particles

Stable aqueous dispersions of sesame oil (SO) were obtained by co-sonication with soybean phosphatidylcholine (PC) in the SO mole fraction range of 0.1-0.8. In order to clarify the dispersal mechanism, the dispersed particles were characterized and the interaction of SO with PC was investigated using several physicochemical techniques. Dynamic light scattering measurements showed that the diameter of the dispersed particles was 40-60 nm. The trapped aqueous volume inside the particles was determined fluorometrically using the aqueous space marker, calcein. The trapped volume in the SO/PC particles decreased remarkably with the addition of SO into small unilamellar vesicles of PC. The decline in fraction of vesicular particles was also confirmed by fluorescence quenching of N-dansylhexadecylamine in the PC membrane by the addition of the quencher CuSO4. These results indicate that the excess SO separated from the PC bilayers is stabilized as emulsion particles by the PC surface monolayer. Monolayer-bilayer equilibrium of SO/PC mixtures was estimated by measurements of spreading and collapse pressures. The results showed that the coexistence of emulsion particles (surface monolayer of PC + core of SO) with vesicular particles (bilayer) was critically important for the formation of stably dispersed particles of the lipid mixture.

Hybrid motor with H(+)- and Na(+)-driven components can rotate Vibrio polar flagella by using sodium ions

The bacterial flagellar motor is a molecular machine that converts ion flux across the membrane into flagellar rotation. The coupling ion is either a proton or a sodium ion. The polar flagellar motor of the marine bacterium Vibrio alginolyticus is driven by sodium ions, and the four protein components, PomA, PomB, MotX, and MotY, are essential for motor function. Among them, PomA and PomB are similar to MotA and MotB of the proton-driven motors, respectively. PomA shows greatest similarity to MotA of the photosynthetic bacterium Rhodobacter sphaeroides. MotA is composed of 253 amino acids, the same length as PomA, and 40% of its residues are identical to those of PomA. R. sphaeroides MotB has high similarity only to the transmembrane region of PomB. To examine whether the R. sphaeroides motor genes can function in place of the pomA and pomB genes of V. alginolyticus, we constructed plasmids including both motA and motB or motA alone and transformed them into missense and null pomA-paralyzed mutants of V. alginolyticus. The transformants from both strains showed restored motility, although the swimming speeds were low. On the other hand, pomB mutants were not restored to motility by any plasmid containing motA and/or motB. Next, we tested which ions (proton or sodium) coupled to the hybrid motor function. The motor did not work in sodium-free buffer and was inhibited by phenamil and amiloride, sodium motor-specific inhibitors, but not by a protonophore. Thus, we conclude that the proton motor component, MotA, of R. sphaeroides can generate torque by coupling with the sodium ion flux in place of PomA of V. alginolyticus.

Effect of divalent cations on the membrane properties of the lipid A analog E5531

To obtain information on the effects of Mg2+ on the membrane properties of the lipid A analog E5531, we determined the size, structure, zeta potential, membrane fluidity, and micropolarity of the aggregates and the permeability of the E5531 membrane after the addition of Mg2+. E5531 forms a vesicle structure and within the molar ratio of [E5531]:[Mg2+] = 1:3, Mg2+ increased the zeta potential of the E5531 membrane, but did not change the size of the aggregates (approximately 20 nm). Within that molar ratio, Mg2+ decreased the membrane fluidity and micropolarity of E5531 and increased the phase transition temperature. Above the molar ratio of [E5531]:[Mg2+] = 1:5, the size of the aggregates was increased, but at [E5531]:[Mg2+] = 1:3, the size of the aggregates was similar to that in the absence of Mg2+ (approximately 20 nm), and we could stabilize the aggregates in rat plasma.

A case of anaplastic large cell (Ki-1) lymphoma of B-cell phenotype, occurring in Waldenström's macroglobulinemia

A case of anaplastic large cell (Ki-1) lymphoma of B-cell lineage occurred in a 59-year-old male with Waldenström's macroglobulinemia. Immunostaining of the lymphoma cells showed sporadic positivity for IgM and occasional positivity for kappa chain. This immunoglobulin specificity is the same as that of plasmacytoid lymphocytes in the bone marrow; therefore anaplastic transformation of Waldenström's macroglobulinemia was strongly suggested. This seems to be the first reported case of anaplastic large cell lymphoma, confirmed by CD30 expression, arising in Waldenström's macroglobulinemia.

Treatment of life-threatening huge atrial myxoma: report of two cases

We herein report two patients with left atrial myxoma who needed an emergency operation. Case 1 was a 48-year-old woman who was injured in a traffic accident and underwent an operation for a right leg fracture. Just after the operation she developed cardiac and respiratory arrest with complaints of chest pain. She was successfully resuscitated and diagnosed to have a left atrial myxoma by echocardiography. Emergency surgery was performed and a giant left atrial myxoma was thus removed from the atrial septum. Case 2 was a 54-year-old housewife who was transferred to our department under the diagnosis of a left atrial myxoma by echocardiography. She complained of dyspnea and chest discomfort. By angiography, the tumor was seen to be partially incarcerated at the diastolic phase. A huge myxoma was removed from the atrial septum which was secured by a patch closure. Cardiac echocardiography can help rule out left atrial myxoma if it is highly suspected. As early surgical mortality is low and the long-term results are good, we strongly believe that patients with cardiac myxoma should be operated on as early as possible, once a diagnosis is made.

Preparation of transparent injectable formulation for lipid A analog E5531

We developed a "pH-jump method" to obtain transparent solutions of E5531, a synthetic lipid A analog, at neutral pH for pharmaceutical injection. E5531 has two pKa: pKa1 = 6.0 and pKa2 = 9.3. At pH 11.0, E5531 was dispersed as a dissociated form, and the phase transition temperature Tc of E5531 was determined to be 30 degrees C using differential scanning calorimetry (DSC). Based on these results, the pH-jump method procedure involves dispersing E5531 at pH 11.0 (above pKa2) at 50 degrees C (above Tc) and mixing with a phosphate buffer to neutralize the pH. No degradated products of E5531 were observed at 50 degrees C for 3 hr during dispersing in the alkaline solution. The turbidity of samples prepared with the pH-jump method was similar to that of water and superior to the samples dispersed directly in neutral pH. This method does not need mechanical power and is suitable for large-scale production.

Functional interaction between PomA and PomB, the Na(+)-driven flagellar motor components of Vibrio alginolyticus

Four proteins, PomA, PomB, MotX, and MotY, appear to be involved in force generation of the sodium-driven polar flagella of Vibrio alginolyticus. Among these, PomA and PomB seem to be associated and to form a sodium channel. By using antipeptide antibodies against PomA or PomB, we carried out immunoprecipitation to verify whether these proteins form a complex and examined the in vivo stabilities of PomA and PomB. As a result, we could demonstrate that PomA and PomB functionally interact with each other.

Formation and structure of stably dispersed particles composed of retinal with dipalmitoylphosphatidylcholine: coexistence of emulsion particles with bilayer vesicles

In order to develop an intravenous formulation of all-trans-retinal (vitamin A aldehyde, VAA) for the treatment of night blindness, VAA and dipalmitoylphosphatidylcholine (DPPC) were sonicated and the dispersions in the VAA mole fraction range of 0.1-0.7 were stable at room temperature for 3 days. In order to clarify the dispersal mechanism, the dispersed particles were characterized and the interaction between VAA and DPPC was investigated using several physicochemical techniques. Dynamic light scattering measurements showed that the diameter of the dispersed particles was 50-70 nm. A limited amount of VAA is incorporated into DPPC bilayer membranes (approximately 5 mole%). The trapped aqueous volume inside the particles was determined fluorometrically using the aqueous space marker calcein and the volume in the VAA/DPPC particles was decreased remarkably with the addition of VAA into small unilamellar vesicles of DPPC. The decline in the fraction of vesicular particles was also confirmed by fluorescence quenching of N-dansylhexadecylamine in the DPPC membrane by the addition of the quencher CuSO(4). These results indicate that the excess VAA separated from the DPPC bilayers is stabilized as emulsion particles by the DPPC surface monolayer. The monolayer-bilayer equilibrium of VAA/DPPC mixtures was estimated by measurement of spreading and collapse pressures. The results showed that the coexistence of emulsion particles (surface monolayer of DPPC+core of VAA) with vesicular particles (bilayer) was critically important for the formation of the stably dispersed particles of the lipid mixture.

Digestible energy expenditure in grazing activity of growing horses

Ten Thoroughbred yearlings (5 females and 5 males) were used to examine the effect of time of grazing on pasture forage and digestible energy (DE) intake, bodyweight gain and DE expenditure in grazing activity. Five females were grazed for 17 h/day (LTG), 5 males were grazed for 7 h/day (STG) and they were fed differently. As a result, DE intake from pasture forage of LTG horses and STG horses was 27.3 and 12.7-13.9 Mcal/day, respectively. The average daily gain (ADG) of LTG and STG horses was 0.37 and 0.39-0.61 kg/day, respectively. The regression lines between DE intake and ADG of both groups were parallel and the difference in DE intake between them was 10 Mcal of DE. It was suggested that DE expenditure in grazing activity (entirely at night) of growing horses was 1 Mcal/h under the conditions of this study.

TMC-66, a new endothelin converting enzyme inhibitor produced by Streptomyces sp. A5008

A new endothelin converting enzyme (ECE) inhibitor, TMC-66 was isolated from the fermentation broth of Streptomyces sp. A5008. The structure of TMC-66 was elucidated by spectroscopic analyses to be a new member of benzo[a]naphthacenequinone class of antibiotics. TMC-66 had a highly selective inhibitory activity for ECE with an IC50 value of 2.9 microM. Taxonomy of the producing strain is also described.

Phytate and phosphorus movements in the digestive tract of horses

This experiment was conducted to study phytate degradation and the effect of dietary phytate level on phosphorus absorption in the gastrointestinal tract of horses. Six Thoroughbred horses were fed diets containing low-phytate diet or high-phytate diet for 5 days. The diets were supplemented with Cr2O3 as an unabsorbable marker. The horses were killed 3 h after the last feeding and digesta in some segments of the intestine were collected. In both dietary groups, the daily passage of phytate phosphorus was decreased in the upper small intestine and in the lower large intestine. The daily passage of phytate phosphorus in the lower large intestine did not differ between these groups. Although the passage of total phosphorus increased in the upper small intestine and in the upper large intestine of both groups, its passage decreased in the lower large intestine. These results suggest that phytate phosphorus is degraded in the upper small intestine and in the lower large intestine of both groups. Phosphorus is suggested to be mainly absorbed in the lower large intestine. Therefore, phytate phosphorus is considered to be easily absorbed in horses because the major site of phosphorus is the lower large intestine where most of phytate is already degraded.

A HMG-CoA reductase inhibitor improved regression of atherosclerosis in the rabbit aorta without affecting serum lipid levels: possible relevance of up-regulation of endothelial NO synthase mRNA

We determined the role of Fluvastatin: HMG-CoA reductase inhibitor on the regression of atherosclerosis following removal of dietary cholesterol. Male rabbits fed a 0.5% cholesterol diet for 12 weeks were divided into three groups: A1, hypercholesterolemic; A2, fed a regular diet for an 12 additional weeks; and A3, fed a regular diet with fluvastatin (2 mg/kg/day). Fluvastatin treatment (A3) did not affect serum lipid levels compared with A2. However, it decreased the atherosclerotic area in the aortic arch and decreased total and esterified cholesterol concentrations in the descending aorta. Tone-related basal NO release in the thoracic aorta was larger in A3 than in A2. eNOS mRNA in vessel was determined by competitive RT-PCR assay. It increased in A1, compared with normal aorta and decreased in A2; however, it did not decrease in A3. This is the first report of a decrease in eNOS mRNA in atherosclerosis after removal of dietary cholesterol and a reversal of it by a HMG-CoA reductase inhibitor, which may contribute to the regression of atherosclerosis.