Biosynthesis of bile acids in cerebrotendinous xanthomatosis. Relationship of bile acid pool sizes and synthesis rates to hydroxylations at C-12, C-25, and C-26.

To examine the defect in side-chain oxidation during the formation of bile acids in cerebrotendinous xanthomatosis, we measured in vitro hepatic microsomal hydroxylations at C-12 and C-25 and mitochondrial hydroxylation at C-26 and related them to the pool size and synthesis rates of cholic acid and chenodeoxycholic acid as determined by the isotope dilution technique. Hepatic microsomes and mitochondria were prepared from seven subjects with cerebrotendinous xanthomatosis and five controls. Primary bile acid synthesis was markedly reduced in cerebrotendinous xanthomatosis as follows: cholic acid, 133 +/- 30 vs. 260 +/- 60 mg/d in controls; and chenodeoxycholic acid, 22 +/- 10 vs. 150 +/- 30 mg/d in controls. As postulated for chenodeoxycholic acid synthesis, mitochondrial 26-hydroxylation of 5 beta-cholestane-3 alpha, 7 alpha-diol was present in all specimens and was 30-fold more active than the corresponding microsomal 25-hydroxylation. However, mean mitochondrial 26-hydroxylation of 5 beta-cholestane-3 alpha,7 alpha-diol was less active in cerebrotendinous xanthomatosis than in controls: 59 +/- 17 compared with 126 +/- 21 pmol/mg protein per min. As for cholic acid synthesis, microsomal 25-hydroxylation of 5 beta-cholestane-3 alpha,7 alpha,12 alpha-triol was substantially higher in cerebrotendinous xanthomatosis and control preparations (620 +/- 103 and 515 +/- 64 pmol/mg protein per min, respectively) than the corresponding control mitochondrial 26-hydroxylation of the same substrate (165 +/- 25 pmol/mg protein per min). Moreover in cerebrotendinous xanthomatosis, mitochondrial 5 beta-cholestane-3 alpha,7 alpha,12 alpha-triol-26-hydroxylase activity was one-seventh as great as in controls. Hepatic microsomal 12 alpha-hydroxylation, which may be rate-controlling for the cholic acid pathway, was three times more active in cerebrotendinous xanthomatosis than in controls: 1,600 vs. 500 pmol/mg protein per min. These results demonstrate severely depressed primary bile acid synthesis in cerebrotendinous xanthomatosis with a reduction in chenodeoxycholic acid formation and pool size disproportionately greater than that for cholic acid. The deficiency of chenodeoxycholic acid can be accounted for by hyperactive microsomal 12 alpha-hydroxylation that diverts precursors into the cholic acid pathway combined with decreased side-chain oxidation (mitochondrial 26-hydroxylation). However, side-chain oxidation in cholic acid biosynthesis may be initiated via microsomal 25-hydroxylation of 5beta-cholestane-3alpha,7alpha,12alpha-triol was substantially lower in control and cerebrotendinous xanthomatosis liver. Thus, separate mechanisms may exist for the cleavage of the cholesterol side chain in cholic acid and chenodeoxycholic acid biosynthesis.

N-phosphoryl derivatives of bisantrene. Antitumor prodrugs with enhanced solubility and reduced potential for toxicity.

The selective phosphorylation of bisantrene (1) affords bis(phosphonoguanidinic acid) 6, a prodrug with enhanced aqueous solubility (as sodium salt 7) at physiological pH. Unlike 1, in a rat tail vein model, no precipitation was observed when bis(phosphonoguanidinic acid) 6 was injected. While in rats 6 hydrolyzed to monophosphonoguanidinic acid 9 with a half-life of ca. 12 min., complete hydrolysis to bisantrene required several hours. The corresponding monophosphonoguanidinic acid 9 was synthesized from bisantrene and also showed good solubility and antitumor activity. While the antitumor activities of 6 in mice were comparable to bisantrene against B-16 melanoma and P-388 and L-1210 leukemias, it was inactive in vitro vs several tumor cell types. Thus, its activity in vivo resulted from its ability to serve as a prodrug for bisantrene.

Potential antiarthritic agents. 2. Benzoylacetonitriles and beta-aminocinnamonitriles.

Benzoylacetonitrile and beta-aminocinnamonitrile are shown to possess potent antiinflammatory activity in the rat adjuvant arthritis model. In a series of phenyl-substituted analogues, only o-, m-, and p-fluorobenzoylacetonitrile and m- and p-fluoro-beta-aminocinnamonitrile retained activity. Additionally, beta-amino-2- and beta-amino-3-thiopheneacrylonitrile and beta-oxo-2- and beta-oxo-3-thiophenepropionitrile exhibited similar activity. These agents are not believed to be acting via prostaglandin synthetase inhibition. The metabolic profile of benzoylacetonitrile is also described.

A double-blind, placebo-controlled, efficacy, safety, and pharmacokinetic study of INN 00835, a novel antidepressant peptide, in the treatment of major depression.

BACKGROUND: INN 00835 is a synthetic pentapeptide with a potential for rapid onset of action as an antidepressant. Its efficacy was investigated in a pilot study in patients diagnosed with major depression. METHODS: Fifty two patients received either active drug - INN 00835 (26 patients) - or placebo (26 patients), subcutaneously at 0.2 mg/kg for 5 consecutive days. The patients were evaluated for an additional 4 weeks after treatment. Efficacy was evaluated by the following psychiatric rating scales: HAMD, MADRS, CSRS, CGI, and VAS. The effect of treatment was also evaluated by using a biochemical marker: changes in blood platelet serotonin (5HT) uptake rates in drug-treated patients compared to those in the placebo group. Plasma concentrations of INN 00835 were measured by LC/MS. RESULTS: Statistical analysis indicated a strong pharmacodynamic correlation between plasma drug concentrations at 1 h after dosing and the reduction in the severity of depression as measured by the psychiatric rating scales. A minimum effective plasma concentration (MEC) of INN 00835 was 5 ng/ml. Statistically significant differences in response to treatment (P<0.05) were found between patients with plasma concentrations above MEC and those in the placebo group, as well as between subjects with plasma concentrations above and below the MEC. The peak effect was observed after the 5-day treatment and the response to treatment persisted during the 4-week follow-up period. The change of 5HT uptake rates after treatment was significantly larger in the drug-treated group than in the placebo group. LIMITATIONS: This was a pilot study conducted in a relatively small population (52 patients) and the limited number of blood sampling times did not allow a comprehensive pharmacokinetic analysis. There was a relatively large placebo response. The results have to be confirmed in future, large scale studies. CONCLUSIONS: INN 00835 appears to be a promising drug for the treatment of major depression.

The effect of treatment with a new antidepressant, INN 00835, on platelet serotonin uptake in depressed patients.

BACKGROUND: INN 00835 (4-fluoro-L-phenylalanyl-trans-4-hydroxy-L-prolyl-L-arginyl-glycyl-trypt ophanamide ditrifluoroacetate) is a synthetic pentapeptide antidepressant with a potential for rapid onset of action. We were interested to see if such action could be correlated with serotonin uptake by platelets. METHODS: In a phase II clinical trial, unipolar depressed patients were administered active drug, INN 00835 or placebo, subcutaneously, at 0.2 mg/kg, once daily for 5 consecutive days. Efficacy of treatment was evaluated by psychometric tests (HAMD, MADS, CSRS, CGI and total VAS). Changes in platelet uptake rates of serotonin (3H-5HT) were measured in plasma from the patients participating in the phase II clinical trial, prior to and immediately after treatment with INN 00835 (19 patients) or placebo (16 patients), to evaluate the effect of treatment with INN 00835 on the rate of platelet 5-HT uptake. RESULTS: The data evaluated by using the psychometric tests indicated a significant response to treatment with INN 00835 after 5 days of dosing. The rates of platelet 5-HT uptake were lower prior to treatment (baseline), and increased after the 5-day treatment period. The change in the uptake rate (deltaVmax) following treatment was significantly larger in the active group than in the placebo group (P < 0.05). The difference between the placebo group and the patients who responded to treatment was even larger. LIMITATIONS: Small number of subjects. CONCLUSION: The data tend to substantiate the use of platelet serotonin uptake as a biochemical marker of effective treatment of depression.

Stimulation of the secretion of dehydroepiandrosterone by melatonin in mouse adrenals in vitro.

Adrenals of young adult male mice kept on a LD 12:12 lighting regimen for three weeks prior to study and harvested at four different circadian stages were incubated for 2 hours with 0.4 IU synthetic ACTH in 2 ml Krebs-Ringer buffer (KR), or with 50, 150, and 450 microM of melatonin in KR containing 0.4 IU ACTH. The addition of melatonin to ACTH leads to a dose dependent stimulation of production and/or secretion of DHEA into the incubation medium irrespective of the circadian stage of harvesting of the adrenals. This relationship is of interest in view of the simultaneous decrease of dehydroepiandrosterone and melatonin in the course of aging, and the effects of these compounds upon aging related changes.

Double-blind, placebo-controlled study of INN 00835 (netamiftide) in the treatment of outpatients with major depression.

This study was designed to determine the safety, efficacy and pharmacokinetics of the antidepressant netamiftide (previously designated name: INN 00835) after 5 or 10 daily doses administered to patients diagnosed with major depression. Netamiftide was administered subcutaneously at a fixed dose of 18 mg/patient per day. Of the 55 enrolled patients, 22 were dosed for 10 days with drug, 11 for 5 days with drug followed by 5 days with placebo and 22 for 10 days with placebo only. The effect of treatment with netamiftide was evaluated by the following psychometric tests: Hamilton Depression Rating, Montgomery-Asberg Depression Rating Scale, Carroll Self-Rating Depression and Clinical Global Impression scales. None of the patients experienced significant adverse effects. A pharmacodynamic correlation (P < 0.05) was found between plasma drug concentrations and response to treatment. Highest plasma concentrations (Cmax) of netamiftide averaging 45.7 ng/ml were observed at 0.25 h after dosing. There were 89% responders in the group with Cmax > or = 45.7 ng/ml (minimum therapeutic concentration) versus 40% in the group with Cmax < 45.7 ng/ml. Onset of action was observed within 48 h after treatment, peak effect was observed at approximately 1 week after treatment and efficacy lasted during a 4-week follow-up period. Netamiftide is a promising antidepressant with rapid onset of action and with an excellent safety profile.

Circadian and circannual rhythms of hormonal variables in elderly men and women.

A group of fourteen men (73 +/- 5 yr of age), and eighteen women (77 +/- 7 yr of age) institutionalized at the Berceni Clinical Hospital, Bucharest, Romania, were studied over a 24-hr span once during each season (winter, spring, summer and fall). All subjects followed a diurnal activity pattern with rest at night and ate three meals per day with breakfast at about 0830, lunch at about 1300 and dinner at about 1830. The meals were similar, although not identical for all subjects during all seasons. On each day of sampling blood was collected at 4-hr intervals over a 24-hr span. Seventeen hormonal variables were determined by radioimmunoassay. Statistically significant circadian rhythms were detected and quantitated by population mean cosinor analysis in pooled data from all four seasons in both sexes for ACTH, aldosterone, cortisol, C-peptide, dehydroepiandrosterone-sulfate (DHEA-S), immunoreactive insulin, prolactin, 17-OH progesterone, testosterone, total T4 and TSH. In women, estradiol and progesterone also were determined and showed a circadian rhythm during all seasons. Total T3 and FSH showed circadian rhythm detection by cosinor analysis in the men only; LH showed no consistent circadian rhythm as group phenomenon in men or women. A circannual rhythm was detected using the circadian means of each subject at each season as input for the population mean cosinor in the women for ACTH, C-peptide, DHEA-S, FSH, LH, progesterone, 17-OH progesterone and TSH. In the men, a circannual rhythm was detected for ACTH, FSH, insulin, LH, testosterone and T3. There were phase differences between men and women in ACTH, FSH and LH. In those functions in which both the circadian and circannual rhythms were statistically significant, a comparison of the amplitudes showed in the women a higher circannual rather than circadian amplitude for DHEA-S. In 17-OH progesterone, TSH and C-peptide, the circadian amplitude in women was larger. In men, the circannual amplitude of T3 was larger than the circadian amplitude and in insulin the circadian amplitude was larger than the circannual amplitude. There was no statistically significant difference between the circadian and circannual amplitudes in the women in ACTH and progesterone and in the men in ACTH and testosterone.

Circadian, weekly, and seasonal variations in cardiac mortality, blood pressure, and catecholamine excretion.

Time of occurrence of cardiac death due to arrhythmia, heart failure, or acute myocardial infarction was recorded in 86 elderly subjects, belonging to a group in whom circadian and circannual rhythms in blood pressure and urinary catecholamine excretion had been studied previously. All patients were retired, with no work responsibilities, and lived--closely-supervised in a home for the aged--on a routine that provided little differences between weekdays and weekends. Cardiac mortality showed a circadian variation, with a peak in the early morning hours, coinciding with the circadian peak in systolic and diastolic blood pressures. A weekly (circaseptan) variation in cardiac mortality was found, with the greatest number of patients dying on Mondays and the least on Thursdays. There were seasonal differences in cardiac mortality, with a peak in July and a broader peak during the cold season (December to February). The former coincides with the circannual peak in diastolic blood pressure, but is unrelated to the seasonal variation in norepinephrine excretion. Circadian, circaseptan, and circannual variations in cardiac mortality appear to be the expression of time-dependent, transient risk states for catastrophic cardiac events, which may lend themselves to preventive treatment.

Circadian rhythms of basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP-3), cortisol, and melatonin in women with breast cancer.

BACKGROUND: Circadian rhythms in plasma concentrations of many hormones and cytokines determine their effects on target cells. METHODS: Circadian variations were studied in cortisol, melatonin, cytokines (basic fibroblast growth factor IbFGF], EGF, insulin-like growth factor-1 [IGF-1]), and a cytokine receptor (insulin-like growth factor binding protein-3 [IGFBP-3]) in the plasma of 28 patients with metastatic breast cancer. All patients followed a diurnal activity pattern. Blood was drawn at 3h intervals during waking hours and once during the night, at 03:00. The plasma levels obtained by enzyme-linked immunoassay (ELISA) or radioimmunoassay (RIA) were evaluated by population mean cosinor (using local midnight as the phase reference) and by one-way analysis of variance (ANOVA). RESULTS: Cortisol and melatonin showed a high-amplitude circadian rhythm and a superimposed 12h frequency. bFGF showed a circadian rhythm with an acrophase around 13:00 with a peak-to-trough interval (double amplitude) of 18.2% and a superimposed 12h frequency. EGF showed a circadian rhythm with an acrophase around 14:20, a peak-to-trough interval of 25.8%, and a superimposed 12h frequency. IGF-1 showed a high value in the morning, which is statistically different (t test) from the low value at 10:00, but a regular circadian or ultradian rhythm was not recognizable as a group phenomenon. IGFBP-3 showed a low-amplitude (peak-to-trough difference 8.4%) circadian rhythm with the acrophase around 11:00 and low values during the night. CONCLUSIONS: (1) Circadian periodicity is maintained in hospitalized patients with metastatic breast cancer. (2) Ultradian (12h) variations were superimposed on the circadian rhythms of the hormones and several of the cytokines measured. (3) Studies of hormones and cytokines in cancer patients have to take their biologic rhythms into consideration. (4) The circadian periodicity of tumor growth stimulating or restraining factors raises questions about circadian and/or ultradian variations in the pathophysiology of breast cancer.

Studies on the 12alpha and 26-hydroxylation of bile alcohols by rabbit liver microsomes.

12Alpha--Hydroxylation of two C27-steroids by rabbit liver microsomes was studied. Optimal assay conditions were determined with 7alpha-hydroxy-4-cholesten-3-one and 5beta-cholestand-3alpha, 7alpha-diol as substrates. The rate of 12alpha-hydroxylation of 7alpha-hydroxy-4-cholesten-3-one was found to be greater than that of 5beta-cholestane-3alpha, 7alpha-diol by ca. 60%. Microsomal 26-hydroxylation of 5beta-cholestane-3alpha7alpha-diol was also measured, and the ratio of 26-hydroxylation to 12alpha-hydroxylation of 5beta-cholestane-3alpha, 7alpha-diol was found to be ca. 0.4. Rabbit liver 12-alphahydroxylase was more active than that of three other species (man, rat, monkey), explaining in part the predominance of cholic acid in rabbit bile.

Chronobiology in laboratory medicine.

A critical amount of information has accumulated over the last decades to allow the application of chronobiology to clinical and laboratory medicine. The tasks faced in laboratory medicine include the quantitative measurement of the multifrequency human time structure in health and disease. For this purpose, it is essential to choose an adequate sample size in order to obtain meaningful results and quantitative endpoints which can be interpreted by inferential statistical techniques. No statistical technique is applicable for all purposes and it is essential that the assumptions underlying each technique and its limitation are well known to the investigator. The multifrequency nature of the human time structure has to be kept in mind in order to avoid erroneous results. Time qualified reference ranges have to be established for high amplitude rhythms. Circadian and/or circannual rhythm alterations have been described as group phenomenon in subjects with epidemiologically determined risk states for common diseases, but will require much further studies for the application to individual subjects. Rhythm parameters are new endpoints in the evaluation of the human time structure in health. Alterations of these parameters may occur as cause or as consequence of disease. Recognition of rhythm abnormalities in disease are critical for a meaningful application of chronopharmacology. Time dependent changes in pharmacokinetics and pharmacodynamics have to be taken into account in the interpretation of drug level determinations. A considerable degree of individuality of timing has been documented in some frequencies. This individuality and the rhythm abnormalities found in disease require the study of reference or marker rhythms. If the complexity of the human time structure is clearly understood and its study pursued in a critical manner with quantitative endpoints, chronobiology opens a new dimension in laboratory and clinical medicine.

Comparison of systemic exposure to nemifitide following two methods of subcutaneous administration to healthy volunteers.

The purpose of this study was to evaluate the safety and pharmacokinetics of nemifitide, a synthetic antidepressant pentapeptide, following its subcutaneous (s.c.) administration by standard needle injection or by a needle-free (Biojecttrade mark) injection and to compare these two routes of administration for systemic exposure. This small-scale, randomized, single-dose, parallel design, open-label pilot study consisted of three treatment groups of four subjects each dosed as follows: group 1: 40 mg of nemifitide administered by standard needle/syringe and groups 2 and 3: 40 and 80 mg nemifitide, respectively, administered by using a needle-free (Bioject injection delivery system. Plasma concentrations of nemifitide were determined by LC/MS/MS in blood samples collected at 10 min and 0.5, 1, 2, 4, 6 and 24 h after dosing. PK parameters, including observed C(max), T(max) and AUC(0-24), were calculated and statistical analysis of the data was conducted. Safety assessments (dosing site evaluations) were done at 0.5, 1, 5 and 24 h after dosing. Vital signs and clinical laboratory tests were taken on day 1 prior to dosing and at 24 h post-dose. Adverse experiences in all subjects were observed only as drug-related local reactions at the injection sites. All were considered mild in severity and transient (resolved by 24 h after dosing). T(max) was observed at 10 min after dose and was the same in all subjects. In the three dosing groups, 1 (40 mg), 2 (40 mg) and 3 (80 mg), observed C(max) values were 226, 245 and 440 ng/ml, respectively, and AUC(0-24) values were 108, 106 and 205 ng.h/ml, respectively. Ratios of AUC(0-24) and observed C(max) for nemifitide in plasma between groups 1 and 2 were within the 80%-125% range, indicating that the two modes of drug administration resulted in similar systemic exposure to nemifitide. Pharmacokinetic parameters (AUC(0-24) and C(max)) indicate dose-proportionality between the doses of 40 and 80 mg.

Seasonal and circadian modifications in the RNA concentration in rat adrenals after swimming effort.

Variation of the adrenal RNA as a reaction to standard physical effort--30 min. of swimming daily for 5 successive days-was studied on adult male white Wistar rats in relation to the season and the hour at which the physical effort was made. The relationship between the seasonal variation and the adrenal adaptation response to swimming was followed up in the interval between March 1972 and December 1974; the circadian variation was examined at 0600, 1200, 1800 and 0000. 1. The circannual differentiation in the response to effort is expressed in the increase of the adrenal RNA concentration, statistically non-significant in spring, maximum in summer and statistically significant in autumn; in winter, the RNA concentration, by its significant decrease as against the controls, expresses an inversion of the adrenal response to effort. 2. Within a 24-hour period the increase in the adrenal RNA concentration under effort is maximum at 1800 and generally higher at night. The fundamental chronobiologic structure of the species seems to interfere significantly the adrenal adaptation to physical effort.

Persistence of circadian rhythms of RNA, DNA and protein in the rat adrenal and thyroid under continuous darkness conditions.

Continuous darkness regimen applied to rats for 30 days did not significantly alter the patterns of the circadian rhythms of RNA, DNA and total protein in the thyroid and adrenals. These results show that the dominant role of light as a "Zeitgeber" cannot be generalized in the case of the biorhythms studied.

Effect of pinealectomy on the circadian rhythms of RNA DNA and protein concentrations in the rat adrenal and testis.

Adrenal and testicular RNA, DNA and protein concentrations were determined in 360 adult male Wistar rats kept under natural lighting conditions with food and water available ad libitum, two and six months after pinealectomy (120 rats) or sham operation (120 rats). A third group of 120 animals was left intact and was studied concomitantly. During each of the two sampling sessions (January and May) subgroups of 5 animals of each of the three groups were sacrificed at 06:00, 12:00, 18:00 and 00:00 over a 72-hour span. The data were analyzed by the single cosinor procedure. The pinealectomized rats showed a desynchronization of their circadian rhythms which 2 months after pinealectomy led to disappearance of detectable rhythms in adrenal RNA and in testicular RNA and DNA concentrations and a marked decrease in the circadian amplitude in adrenal DNA concentration. The adrenal RNA concentration at this time was increased. Six months after surgery circadian rhythms of these functions were again demonstrable as group phenomena but showed in the pinealectomized animals a marked phase difference in relation to the other treatment groups. Both the external and the internal phase relations were still found to be altered 6 months after pinealectomy. Pinealectomy thus leads to prolonged changes in the time structure of the animals which manifest themselves as internal and external desynchronization of metabolic marker rhythms in adrenal and testis.