Mauro Cignarelli

Low dehydroepiandrosterone circulating levels in premenopausal obese women with very high body mass index

Dehydroepiandrosterone (DHEA) has an anti-obesity effect in rodents and reduces body fat in normal men. Therefore, the plasma levels of DHEA were evaluated in nine premenopausal healthy women and in 13 menstrually active nondiabetic obese women, including patients (n = 6) with body mass index (BMI) over 40. In the obese group, a significant inverse correlation between DHEA levels and BMI was found. These results suggest that patients with severe obesity are unable to increase the DHEA adrenal production rate in order to parallel the increase in the hormone metabolic clearance rate (due to enlargement of body fat mass per se). The deficiency of this mechanism might itself contribute to the progressive fat accumulation in severe obesity.

Relation between sex hormones and serum lipoprotein and lipoprotein(a) concentrations in premenopausal obese women.

Lipoprotein(a) (Lp[a]) is generally considered to be a risk factor for the development of cardiovascular disease, but little is known about the possible influence of obesity on the circulating levels of this lipoprotein. The present study was undertaken to examine this aspect in 136 menstrually active women by comparing the serum concentrations of Lp(a) between 72 obese and 64 age-matched nonobese women. Since an adverse effect of androgens and a protective effect of estrogens have been described for plasma lipoprotein profiles in obese women, the relation between the circulating levels of Lp(a) and those of these other hormones was also investigated in obese patients. In addition, other lipoproteins, anthropometric parameters (body mass index and waist-to-hip ratio), and insulin were evaluated. The levels of Lp(a) were not significantly different (Mann-Whitney U test chi 2, 3.59; p = 0.0582 [NS]) between obese (rank sum, 5,367) and control (rank sum, 3,949) women; in addition, the percentage of patients with high Lp(a) levels (cutoff defined at 30 mg/dL) did not differ between the two groups (obese women, 30%; control, 21.8%; chi 2, 0.90; two-sided p = 0.341 [NS]). Moreover, no correlation was found between Lp(a) and body mass index. Lastly, when the Lp(a) prevalence odds ratio for obesity was examined by adjusting the levels of this lipoprotein for age, triglycerides, total cholesterol, and high density lipoprotein cholesterol, the probability value (0.88) was far from significant. In obese women, no correlation was found between the logarithmically transformed Lp(a) concentrations and all the other variables evaluated in the study. In conclusion, the present study shows that the circulating levels of Lp(a) are not influenced by body weight and cardiovascular risk factors commonly associated with obesity, such as enhanced androgenic activity, hyperinsulinemia, adverse lipoprotein profile, and abdominal fat accumulation.

Influence of free testosterone on antigen levels of plasminogen activator inhibitor-1 in premonopausal women with central obesity

Women with upper body obesity are at increased risk for cardiovascular disease (CVD). Several studies have demonstrated a reduced fibrinolytic activity in these patients, mainly due to an enhanced activity of plasminogen activator inhibitor-1 (PAI-1). Since an increase of androgenic activity is a feature of central obesity in women, the present study was aimed at evaluating the possibility of a relationship between androgens and PAI-1 (antigen and activity) in 20 premenopausal women, 10 with upper body obesity and 10 controls. In obese women, PAI-1 antigen showed a positive Pearson correlation with free testosterone (FT), insulin, c-peptide, triglycerides (TG), and waist to hip ratio (WHR) (P less than .01), whereas PAI-1 activity correlated positively only with insulin and WHR (P less than .01). In control women, PAI-1 antigen and activity were positively related only to TG (P less than .01). When we applied the multiple regression model with stepwise backward method to our data, both PAI-1 antigen and activity did not maintain any significant association. However, when the data from both the groups were pooled (n = 20), and PAI-1 antigen was considered as the dependent variable, body weight (Sig T = 0.0001), TG (Sig T = 0.0053), FT (Sig T = 0.013), and luteinizing hormone (LH) (Sig T = 0.0474) met the stepwise criteria, suggesting an independent effect of each of these parameters on PAI-1 antigen. On the other hand, when PAI-1 activity was tested as the dependent variable, only body weight maintained a significant relationship with this parameter (Sig T = 0.0006).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of the repetitive administration of progesterone by nasal spray in postmenopausal women

OBJECTIVE To study the effects of 10 days of nasal spray P treatment on P serum levels and the endometrium. DESIGN Prospective. SETTING University Medical School. PATIENTS Eight postmenopausal women received oral conjugated estrogens at a daily dose of 0.625 mg for 4 weeks immediately before vaginal surgery for prolapse. For the first 9 of the last 10 days the patients also received a nasal spray dosage of 11.2 mg P three times a day; on the 10th day they received only one dose. MAIN OUTCOME MEASURES Blood samples were taken at 8:00 A.M. on treatment days 1, 3, 5, 7, 10, and 11 to follow P serum concentration levels. Endometrial samples for histologic examination were collected before P administration and immediately after surgery to evaluate the end-organ effect. RESULTS Mean P serum levels increased sixfold after 9 days of nasal spray P administration [from 0.612 +/- 0.280 ng/mL (1.958 +/- 0.896 nmol/L) to 3.925 +/- 1.553 ng/mL (12.560 +/- 4.970 nmol/L)] and declined thereafter, returning to the before treatment levels 24 hours after the last administration. In all subjects, the first histologic evaluation showed proliferative endometrium; the second showed clear secretive changes. CONCLUSIONS Repetitive nasal spray P administration for 10 days in postmenopausal women led to increasing P serum levels and, when the estrogen stimulation was adequate, to secretory changes in the endometrium (end-organ effect).

Nasal spray vs oral administration of bromocriptine : Pharmacology and effect on serum prolactin in puerperal women

The oral administration of bromocriptine induces a variety of side-effects in about 50–70% of patients, the most common being nausea and vomiting, probably related to the local gastrointestinal effect of the drug. Nasal administration makes it possible to avoid intestinal and liver metabolism. This study compared the serum concentrations of bromocriptine and prolactin (PRL) in twenty puerperal women who had asked to discontinue breast feeding and were randomized to receive a single oral (2.5 mg) or nasal spray dose (0.8 mg) of bromocriptine. Serum bromocriptine and PRL concentrations were measured at various times before and after drug administration. At 15 min, the circulating concentrations of bromocriptine were about eight times higher after nasal than after oral administration; peak serum concentration (CMax) was reached respectively 45 min and 60 min after administration, and was about three times higher after nasal administration (314±102 pg/ml vs 112.30±34.47 pg/ml). The reduction in serum PRL concentrations was also more rapid in the nasally-treated group reaching the normal assay range of < 20 µg/l within two as against five hours post-administration. Four orally-treated patients complained of nausea; in the nasally-treated group, six patients reported only a mild endonasal burning that disappeared within a few minutes of administration. Our results suggest that the nasal administration of bromocriptine may lead to a reduction in the required overall dose and fewer gastrointestinal side-effects, and may therefore improve therapy compliance.

Nasal spray administration of bromocriptine: pharmacology and effect on serum prolactin level in puerperal women

This study was aimed at investigating the absorption of nasally administered bromocriptine and its effect on serum prolactin level. Fifteen physiologically hyperprolactinemia women who had asked to discontinue breast feeding received a single nasal spray administration of 0.8 mg bromocriptine. Serum prolactin levels were measured by radioimmunoassay at 30 and 15 min before drug administration, at the time of administration and at 15, 30, 60, 120, 240, 480 and 720 min after administration; bromocriptine was radioimmunoassayed in only five of the patients from time 0 to 720 min after administration. Serum bromocriptine levels increased rapidly after administration, reached a maximum at 120 min and thereafter declined slowly over the subsequent 10 h. As the bromocriptine level increased there was a decline in the serum prolactin level. The first significant decline in serum prolactin level compared with the baseline level occurred at 30 min after administration and the level continued to decrease significantly until time 120 min. Four hours after administration the mean serum prolactin level was within the normal assay range. The maximum decline in serum prolactin level was reached at 720 min after administration. Correlation analysis between serum bromocriptine and prolactin concentrations yielded a significant negative value between times 0 and 120 min after administration. There was no significant change in mean orthostatic systolic or diastolic blood pressure or in mean heart rate. Only one patient complained of headache and dizziness; another experienced mild transient nausea, and none had vomiting. Ten patients (66.67%) reported light endonasal burning and an unpleasant taste which subsided after a few minutes; no patient showed nasal irritation at nasal examination. In conclusion, nasal administration of 0.8 mg bromocriptine was effective in reducing the serum prolactin level for more than 12 h after administration without inducing significant side-effects.

Duration of residual B-cell function in maturity-onset diabetes.

SummaryIn order to evaluate factors influencing the duration of residual B-cell function in maturityonset diabetics we investigated 104 patients (age 60±11 years) with a mean duration of disease of 11.3±8.7 years by measuring fasting C-peptide (FCP) and fasting blood glucose levels (FBG), C-peptide increment after a standardized breakfast and both mean diurnal plasma glucose (MBG) and mean diurnal C-peptide levels (MCP). C-peptide levels were found to be reciprocally dependent on both the age at onset (positively) and, conversely, on the duration of diabetes (y=0.75+0.026x1−0.049x2; R=0.52, t1=2.76, t2=−4.08). In particular, the present B-cell secretory capacity appears to be lower the younger the patients were at onset, thus suggesting that inherent impairment of B-cell capacity may play a crucial role in determining age at onset of type II diabetes and thus the duration of their residual B-cell function. Moreover, by analyzing separately the data from patients treated with insulin and oral agents respectively, we found that the influence of the duration of the disease on the rate on B-cell exhaustion is unrelated to the mode of treatment even though B-cell capacity at onset appears to be more severely reduced in insulin-treated subjects who, apart from anything else, were younger at onset. In addition, no significant difference was found in FCP levels between patients showing MBG values above or below 160 mg/dl (1.76±0.66vs 1.57±0.68 ng/ml), whereas MCP values were lower in patients with MBG above 160 mg/dl (2.14±0.92vs 2.55±0.88 ng/ml; p<0.05) who, on the other hand, showed significant reduction in the C-peptide response to breakfast. These data suggest that prolonged metabolic derangement may impair the physiological response of B-cells and eventually lead, via B-cell overstimulation, or via a gap between synthesis and release of insulin, or through other as yet poorly understood mechanisms, to earlier insulin dependence in maturity-onset diabetic patients.

Renal Excretion of Arginine-Vasopressin in Microalbuminuric Diabetic Patients

Enhanced activity of haemodynamic hormones have been reported to be involved in the development of renal lesions of diabetic kidney1,2. Apart from other pressor factors even plasma arginine-vasopressin (AVP) have been found to be increased in uncontrolled diabetic patients very probably reflecting both a hypovolemic status and an increase in “effective” extracellular fluid osmolality; however, high circulating AVP levels have also been observed in certain well controlled diabetic patients thus suggesting that an alteration of mechanisms regulating AVP secretion exists in diabetes mellitus3,4.