Effects of interferon-alpha on cytochrome P-450 isoforms 1A2 and 3A activities in patients with chronic hepatitis C.

BACKGROUND/AIM: The risk of adverse drug interactions with interferon-alpha has been poorly assessed. The aim of our study was to establish whether administration of interferon-alpha at therapeutic doses in patients with chronic hepatitis C may have significant inhibitory effects on other drug metabolism. The study was focused on cytochromes P-450 1A2 and 3A, two major isoforms involved in the metabolism of numerous substrates. METHODS: Eighteen patients with chronic active hepatitis C requiring an interferon-alpha treatment were studied. Cytochrome P-450 1A2 activity was determined on the basis of an in vivo caffeine metabolism study. Cytochrome P-450 3A activity was determined according to in vivo cortisol metabolism into 6-beta-hydroxycortisol. Both activities were determined 1 month before, at initiation and 1 month after interferon-alpha therapy (3 x 10(6) units, three times a week). RESULTS: There were no significant differences in the caffeine index (CYP 1A2) and in the 6-beta-hydroxycortisol/free cortisol urinary ratio (CYP 3A) before and after alpha interferon treatment CONCLUSION: Chronic administration of interferon-alpha at therapeutic doses does not change in vivo cytochrome P-450 1A2 and 3A activities. These results support the suggestion that drugs metabolized by these isoenzymes may be used together with interferon-alpha in patients with chronic hepatitis C without significant risks of drug interactions.

Relationship between insulin sensitivity, obesity, body fat distribution and beta-endorphinaemia in obese women.

OBJECTIVE: To study the associations of obesity (as body mass index (BMI)), of body fat distribution (as waist to hip ratio (WHR)) and of beta-endorphinaemia (beta-EP-aemia) with fasting insulin and glucose concentrations, with insulin secretion (as first phase insulin response (FPIR)) and with insulin sensitivity (SI) in obese women. DESIGN: a cross-sectional study of insulin sensitivity in obese women. SUBJECTS: 45 obese women (age: 20-70 y, BMI: 27-50). MEASUREMENTS: Frequently sampled intravenous glucose tolerance test (FSIGTT), FPIR, fasting glucose, fasting insulin, BMI, body fat topography (WHR), beta-EP-aemia, plasma ACTH. RESULTS: In univariate analysis the following positive associations were observed: fasting glucose with age and WHR, fasting insulin with BMI and WHR, beta-EP plasma concentration with WHR; SI was negatively associated with BMI, WHR and beta-EP plasma concentrations. This pattern of associations remained unaltered in multivariate analysis including age, BMI and WHR as independent variables. The contribution of beta-EP plasma concentrations to SI variability was corroborated by a stepwise multiple regression analysis: 53.8% of SI variation could be explained by BMI (30.7%), by beta-EP plasma concentrations (17.2%) and by WHR (5.9%). Finally, women were divided into two groups according to whether they had a peripheral (P-BFD, WHR < or = 0.80, n = 24) or an abdominal (A-BFD, WHR > or = 0.85, n = 16) body fat distribution. After adjustment for age and BMI, SI values were lower while beta-EP and ACTH plasma concentrations were higher in the A-BFD compared to the P-BFD group. In this latter group, 54.8% of SI variation was explained by the same variables as in the whole group. In the A-BFD group, higher WHR was associated with lower FPIR. CONCLUSIONS: 1) The major finding of this study is that, in non-diabetic obese women (especially those with a P-BFD), higher beta-EP plasma concentrations are associated with lower insulin sensitivity. This association is independent of both the magnitude of obesity and the pattern of fat distribution, although these two parameters are strong predictors of SI. 2) The major reduction in SI observed in women with A-BFD probably results from the additive effects of obesity, of elevated beta-EP plasma concentrations and of metabolic and endocrine alterations in relation with the central pattern of fat distribution.

[Measurement of salivary cortisol with four commercial kits]. / Mesure du cortisol salivaire par quatre trousses du commerce.

Salivary cortisol was determined with four commercially available immunoassays: one enzyme-immunoassay (Cortisol Biotrol), two fluoro-immunoassays (TDX, Abbott; Stratus, Baxter) and one radioimmunoassay (Coat-A-Count, Behring). In order to improve the sensitivity of these immunoassays, it was necessary to increase sample volumes. Thus an extraction step had to be included in the procedure. It was performed with either methylene chloride or Bond Elut. However, the Coat-A-Count kit may be applied directly on salivary aliquots. The results obtained were compared to those yielded by the reference technique which includes a chromatographic step on Sephadex LH 20. According to the present data (n = 20) no kit appears to be adequate for salivary cortisol measurement at any level, at least in the conditions applied in this study. However, the introduction of a chromatographic step in the procedure improved greatly the specificity. Nevertheless, the best results were obtained with the Coat-A-Count kit. Indeed, they were generally similar to those of the reference technique, but some discrepancies were observed at low levels.

Dysregulation of the hypothalamo-pituitary axis in rheumatoid arthritis.

OBJECTIVE: To study the dynamic response of the hypothalamo-pituitary- adrenal axis and of prolactin (PRL) pituitary secretion in rheumatoid arthritis (RA). METHODS: We performed a cortisol releasing hormone (CRH) provocation test followed by determination of adrenocorticotropin hormone (ACTH), beta-endorphin, and cortisol concentration, and then a thyrotropin releasing hormone (TRH) provocation test followed by assessment of PRL pituitary secretion in 10 patients with RA and 5 control subjects. All were women under 40 years of age. Hormone concentrations were assessed by radioimmunoassay. RESULTS: Basal PRL cortisol, and ACTH concentrations were similar in patients with RA and controls. We observed a dissociation between the pituitary secretion of beta-endorphin and of ACTH in response to CRH in RA. The ACTH peak and total ACTH production (area under the curve, AUC) were similar in the 2 groups. In contrast, basal beta-endorphin was increased in RA (12.6 +/- 1.41 vs 8.29 +/- 0.144 pg/ml), and the response upregulated (AUC: 83,080 +/- 12,000 vs 54,200 +/- 2400) after CRH compared to controls (p < 0.05). Cortisol adrenal response curve was blunted, but did not reach statistical significance. In contrast, the PRL response to TRH was increased at 120 and 150 min (3461 +/- 303 vs 1897 +/- 520 muIU/ml)(p < 0.01) in patients with RA, independent of disease activity. CONCLUSION: We observed upregulated pituitary PRL secretion in RA, and a dissociation of ACTH stress. The implication concerning the neuroendocrine system in the chronic immune response in RA is discussed.

Cerebrospinal fluid beta-endorphin and cortisol study in Rett syndrome.

An evaluation of cerebrospinal fluid and plasma beta-endorphin and cortisol levels was performed in 15 girls affected with classic Rett syndrome. There were no differences between the patient group and the control group in plasma cortisol and beta-endorphin levels. But in Rett syndrome, a significant increase in beta-endorphin was noted in the cerebrospinal fluid, with an elevation of the cerebrospinal fluid/plasma beta-endorphin ratio and a decrease in cerebrospinal fluid cortisol. A substantial overlap between patients and control group diminishes the diagnostic value of cerebrospinal fluid beta-endorphin assay in girls suspected of having Rett syndrome.

[Rett syndrome. A report of fifteen cases]. / Le syndrome de Rett. A propos de quinze observations.

In its typical form, Rett syndrome is characterized by the development, towards the end of the first year of life, of neurologic abnormalities in a formerly healthy girl. Our analysis of 13 observations of "classical" Rett syndrome shows that the most common findings include cognitive regression, autistic behavior, hypotonia, apraxia, and very suggestive stereotyped movements. Two other cases emphasize the problems raised by mild, atypical or incomplete forms. At present, there is no biological or morphological marker for this syndrome whose pathophysiology is unknown. Increased levels of beta-endorphins in the cerebrospinal fluid may prove to be a marker and suggests therapeutic possibilities.

The increase in urinary excretion of 6 beta-hydroxycortisol as a marker of human hepatic cytochrome P450IIIA induction.

1. Urinary excretion of 6 beta-hydroxycortisol, hepatic microsomal cortisol 6 beta-hydroxylase and the specific content of several forms of cytochrome P450 were measured in 8 to 14 patients before and after treatment with rifampicin (600 mg orally per day for 4 days). 2. Rifampicin treatment produced an average five fold increase in daily excretion of urinary 6 beta-hydroxycortisol. 3. Cortisol 6 beta-hydroxylase activity increased from 15 +/- 6 pmol min-1 mg-1 in organ donors (considered as 'control subjects') to 87 +/- 31 pmol min-1 mg-1 in rifampicin treated patients. 4. Among three forms of human P450 (P450IA, IIC and IIIA), (1), (2), measured by Western blots, only P450IIIA was significantly induced by the antibiotic. 5. Only antibodies against P450IIIA selectively inhibited cortisol 6 beta-hydroxylase in human liver microsomes. 6. Cortisol 6 beta-hydroxylase was correlated with P450IIIA specific content. 7. The urinary level of 6 beta-hydroxycortisol correlated with liver microsomal cortisol 6 beta-hydroxylase and P450IIIA specific content. 8. We conclude that P450IIIA is predominantly responsible for cortisol 6 beta-hydroxylase activity in human liver microsomes and that urinary 6 beta-hydroxycortisol is a marker of the induction of this cytochrome P450.

Correlations between free plasma estradiol and estrogens determined by bioluminescence in saliva, plasma, and urine during spontaneous and FSH stimulated cycles in women.

Estrone and estradiol (E1 + E2) concentrations in saliva were compared with four other parameters of estrogen status in five normal ovulatory women and ten FSH stimulated women selected for an in vitro fertilization program. E1 + E2 in saliva, plasma, and urine were assessed by a rapid, specific and sensitive enzymatic assay using bioluminescence. The free fraction of plasma estradiol was determined by equilibrium dialysis and total plasma estradiol by conventional radioimmunoassay. The pattern of E1 + E2 variation in saliva was similar to that of free plasma estradiol and the two parameters were correlated in both spontaneous and stimulated cycles. However, the lower correlation coefficient (r = 0.52, P less than 0.001) in spontaneous cycles compared with the high (r = 0.96, P less than 0.001) in the stimulated cycles shows that salivary E1 + E2 could be representative of plasma free estradiol in stimulated cycles but not in normal cycles. The free fraction of plasma estradiol reproduced the variation of total plasma estradiol in spontaneous as well as in FSH stimulated cycles and both parameters were strongly correlated (r = 0.91, P less than 0.001 and r = 0.90, P less than 0.001), respectively. The data show that salivary E1 + E2 concentrations are highly representative of the free fraction of E2 in plasma and at a lesser extend (r = 0.72, P less than 0.001) of total plasma E2 in FSH stimulated cycles.

Follicular steroids in relation to oocyte development and human ovarian stimulation protocols.

Oocytes of pre-ovulatory follicles were collected by laparoscopy for in-vitro fertilization in 118 women. Patients were treated either during the natural cycle, or after induction of ovulation with clomiphene citrate, or with human menopausal gonadotrophin (HMG), or clomiphene citrate combined with HMG. The oestrogens (oestrone + oestradiol) and total aromatizable androgens (androstenedione, testosterone and dehydroepiandrosterone and its sulphate) were assayed in follicular fluids using an enzymatic method. The levels of progesterone, 17 alpha OH-progesterone, thromboxane, and prostaglandins (PGE2 and PGF2 alpha) were determined by radioimmunoassay. The best follicular fluid indicator of oocyte fertilization in vitro was the A/E ratio, which was less than 1 when the oocyte was fertilized in vitro and led to a pregnancy. The lowest value for the A/E ratio was obtained with spontaneous ovulation protocols. Regardless of oocyte development, the progesterone level was always greater than 2000 ng/ml, and the PGE2/PGF2 alpha ratio was greater than 1 in all stimulated cycles. Our investigations show that a combination of clomiphene citrate and HMG provides the best stimulation, on the basis of follicular fluid analysis and the outcome of fertilized oocytes.

[Pregnancies by fertilization in vitro. Biochemistry of the follicular fluid]. / Grossesses par fécondation in vitro. Biochimie du liquide folliculaire.

Fifty four follicular fluids containing 41 oocytes were sampled from 6 patients in which at least one pregnancy was obtained after IVF. Their biochemical composition has been correlated with the follicle maturity and oocyte quality. Three components have been assayed: steroids, prostanoids, proteolytic enzymes. Determinations of estrogens and total aromatisable androgens were carried out by the enzymatic technic of Nicolas and al.; progesterone and 17 OH progesterone by RIA. Development of in vitro cultured and fertilized oocytes appears to be improved when progesterone and estrogens concentrations in the follicular fluid are above 2 000 and 600 ng/ml respectively, with an A/E ratio under 1. On the other hand, prostanoids (T X B2, PGE2, PGF2 alpha determined by RIA) and proteolytic enzymes : (collagenolytic and kallikrein type activities) seemed related to ovulatory activity rather than to oocyte quality.

[Enzymatic determination of urinary estrone and estradiol: correlations with plasma estradiol in the menstrual cycle in women]. / Dosage enzymatique de l'estrone et de l'estradiol urinaires: corrélations avec l'estradiol plasmatique au cours du cycle menstruel chez la femme.

Enzymatic determination of urine estrone and estradiol concentrations were done daily during a menstrual cycle in six female volunteers. The results were compared with plasma estradiol determined by radioimmunoassay in the same patients. The pattern of estrone and estradiol excretion in morning urine sample fairly reproduced plasma estradiol variations and a good correlation was observed (r = 0.78). The urine pattern of estrone and estradiol variation determined by the enzyme assay can be considered as a good index of oestrogen secretion. The preovulatory peak of estrone and estradiol was observed in urine the day before or the same day as the LH peak. Estrone and estradiol concentration in urine doubled the mean value of the concentration of the follicular phase several days before the LH peak giving a useful indication for prediction of ovulation.

[Persistant pubertal gynecomastia. Biological study (author's transl)]. / Gynécomasties pubertaires persistantes. Etude biologique.

17 cases of peristant pubertal gynecomastia (which differs from physiologic breast enlargement by their volume and duration) were studied. Plasma estrogens and urinary phenol steroids excretion were found higher than in normal boys. The main biological finding in these subjects was a decrease of the plasma testosterone/estradiol ratio, and a moderate but transient increase in plasma prolactin. LH and FSH were within the normal range. In the mammary tissue, no estrogen receptor was detectable and aromatase activity was in the same range as in adipose tissue. Pathological examination showed a simulataneous proliferation of galactophoric and fibroblastic stroma. Thus, persistant pubertal gynecomastia could be related to an elevated sensitivity of the mammary tissue to a moderate increase of plasma estrogens. Such a sensitivity could be due to an insufficient masculinization of the mammary anlage during the intra-uterine life.

[Comparison of postoperative blood cortisol levels after neuroleptanalgesia and extradural anesthesia]. / Comparaison de la cortisolémie post-opératoire après neuroleptanalgésie et anesthésie extra-durale.

Postoperative plasma cortisol levels were measured in two series of surgical patients who had undergone a gynaecological operation, with respectively 17 and 16 subjects. Samples were drawn on D0 6pm, D1 8am, D2 8am and D3 8 am. A reference sample had been taken before the premedication on D0 at 8 am. The first series had been anaesthetised using a dextromoramidedroperidol type neuroleptanalgesia followed by postoperative analgesia by a noramidopyrine compound. The second series required epidural anaesthesia followed by postoperative analgesia by the injection of lidocaine at constant rate, interrupted between the last two samples. In the neuroleptanalgesia group: from a basal level of 470 nmol.l-1, plasma cortisol rose to 800 nmol.l-1 (p less than 0.01) on D0 at 6 pm to subsequently remain on a plateau between 500 and 550 nmol.l-1 (NS) within the normal physiological limits for the laboratory. In the epidural group, from a basal level of 420 nmol.l-1, plasma cortisol rose to 1000 nmol.l-1 (p less than 0.01) to return to basal levels only on D3: 450 nmol.l-1 (NS) with intermediate values of 700 and 630 nmol.l-1 (respectively: p less than 0.001 and p less than 0.05). Statistical comparison between the two groups showed that the increase in cortisol in the epidural group in relation to the other was significant throughout the period of administration of lidocaine at constant flow rate: p less than 0.05 on D0 at 6pm, D1 and D2. The results are discussed.

[Estrogen receptors in uterine fibromyomas]. / Les récepteurs des oestrogènes dans les fibromyomes utérins.

The authors have sought the existence of cellular hyper-receptivity in susceptible cells in order to explain the transformation of normal uterine muscle fibres into tumours, because of the absence of true biological proof of hyperoestrogenization in fibromyomata. The total of uterine receptors for oestradiol (the total number of accessible receptors or those in which endogenous oestrogens had been taken up) were measured in normal myometrium and in fibroids removed at myomectomy or at hysterectomy. The oestradiol receptors are significantly raised in fibromyomatous tissue when the results are expressed as femtomoles per mg. of protein. All the same, there is no significant difference to be found when the results are expressed in micrograms of DNA, which leads to the supposition that there is no significant difference in the concentration of oestrogen receptors in the two types of cells. The cause of the cellular multiplication of fibromyomatous tissue should therefore be sought at another level.

[Biological and hormonal balance during oral nutrition, exclusive perenteral and mixed nutrition in children]. / Equilibre biologique et hormonal au cours de la nutrition orale, parentérale exclusive et mixte chez l'enfant.

Exclusive parenteral nutrition and mixed feeding provided by the infusion of a solution of amino-acids, glucose and trace elements by a drip method, result in changes in biological and hormonal balance which have been compared with balance in the child on normal oral feeding. The 24-hour cortisol cycle tends to be attenuated. Blood glucose and, above all, blood insulin levels show major variations. Plasma free fatty acid levels, stable in exclusive parenteral nutrition, in general vary with mixed nutrition. On the basis of these findings, a constant flow should be ensured by use of a pump during exclusive parenteral nutrition. In mixed feeding, meals should be frequent and energy supplies given in the form of slowly absorbed carbohydrates.