Perioperative cortisol can predict hypothalamus-pituitary-adrenal status in clinically non-functioning pituitary adenomas

BACKGROUND

Peri-operative steroids are administered routinely to patients with pituitary adenoma undergoing transsphenoidal adenomectomy (TSA).

AIM

To evaluate hypothalamic-pituitary-adrenal (HPA) axis before and after programmed endoscopic TSA (E-TSA) in patients with clinically non-functioning pituitary macroadenoma (NFPA).

DESIGN

Open prospective.

SETTING

Tertiary referral hospitals.

PATIENTS

Seventy-two consecutive patients (20-87 yr, 37 males).

INTERVENTIONS

Adrenal steroid replacement therapy (ASRT) was given only in patients with hypocortisolism [08:00 h cortisol (F) <8 microg/dl].

MAIN OUTCOME MEASUREMENTS

After ETSA, achieving wide (>90%) selective resection of the adenoma in all, F and clinical picture were checked at day 2. The low-dose (1 microg) ACTH test (LDACTH) was performed at 6 weeks and repeated at 12 months.

RESULTS

Hypocortisolism was present pre-operatively in 14 patients (19.4%), persisted post-operatively in all but one, and was detected de novo at the post-operative day 2 control in 6 (10.3%). In all but one the post-operative day 2 basal F and peak F during LDACTH test were concordant. No patient whose F was > 8 microg/dl was treated with ASRT or developed symptoms of adrenal failure during the follow-up (1-11 yr, median 5).

CONCLUSIONS

HPA function is usually preserved in NFPA and is infrequently impaired after complete tumor removal by E-TSA. The 08:00 h. plasma cortisol evaluation before and 2 days after surgery, using as cut-off the value of 8 microg/dl, allows full evaluation of HPA status. Peri-operative steroid treatment should be given only in patients with hypocortisolism.

Efficacy of the new long-acting formulation of lanreotide (lanreotide Autogel) in somatostatin analogue-naive patients with acromegaly

OBJECTIVE

To evaluate efficacy and safety of lanreotide autogel (ATG) 120 mg injections every 4-8 weeks in somatostatin analogue-naïve patients with acromegaly.

DESIGN

Open, non-comparative, phase III, multicenter clinical study.

METHODS

Fifty-one patients (28 women, aged 19-78 yr): 39 newly diagnosed (de novo) and 12 who had previously undergone unsuccessful surgery (post-op, 11 macro and 1 micro) were studied. ATG 120 mg was initially given every 8 weeks for 24 weeks and subsequently changed according to GH levels: if <or=2.5 microg/l every 8 weeks (group A, 17 patients); if 2.5-5 microg/l every 6 weeks (group B, 15 patients); and if >5 microg/l every 4 weeks (group C, 19 patients). Treatment duration was 48-52 weeks. The primary objective was to control GH and IGF-I levels (GH<or=2.5 microg/l and IGF-I normalized for age/gender). Secondary objectives were to assess GH, IGF-I, and acid-labile subunit (ALS) decrease, improvement of clinical symptoms and quality of life (QoL).

RESULTS

GH levels normalized in 32 patients (63%), similarly in de novo and post-op patients (72% vs 50%, p=0.48); in 100% of group A, in 73% of group B and in 21% of group C (p<0.0001). IGF-I levels normalized in 19 patients (37%), similarly in the de novo and post-op patients (33% vs 50%, p=0.48): in 65% of group A, 33% of group B, and in 16% of group C. Circulating GH levels decreased by 80+/-17%, IGF-I levels by 44+/-27%, and ALS by 30+/-17%. Symptoms (hyperhidrosis (68.6%), swelling (68.6%), asthenia (58.8%), spine arthralgia (54.9%), and paresthesias (52.9%) and QoL (from 9.1+/-7.9 to 6.1+/-6.6) significantly improved (p<0.001). No patient withdrew from the study because of adverse events (AE). The most frequent AE was diarrhea (76.2% of patients): at study end 16 mild and 1 moderate diarrhea were recorded. Gallstones developed in 12% of patients.

CONCLUSION

ATG 120 mg in somatostatin-naïve patients with acromegaly controls GH secretion in 63% and IGF-I secretion in 37% during a 48-52 week period without any difference between de novo and post-op patients. The treatment was associated with improvement in clinical symptoms and QoL and with a good, safe profile.

Somatostatin analogs and gallstones: a retrospective survey on a large series of acromegalic patients

CONTEXT

Development of gallstones (GS) is reported during the use of somatostatin analogs (SA) that are at present the mainstay for the medical treatment of acromegaly.

OBJECTIVE

To review the prevalence and clinical and biochemical correlates of GS in acromegalic patients.

DESIGN AND SETTING

Retrospective survey on hospital records in acromegalic patients followed up in the last 20 yr in tertiary referral centers.

PATIENTS

Four hundred and fifty-nine patients (272 females).

MAIN OUTCOME MEASURES

According to SA use and GS occurrence, patients were divided in 4 groups: 1) treated with SA without GS (SA+GS-), 2) GS developed while on SA (SA+GS+), 3) GS without SA use (SA-GS+), 4) neither GS nor SA (SA-GS-).

RESULTS

Patients were unevenly distributed in the 4 groups: 232, 125, 38, 64, respectively, pointing to a prevalence of GS in acromegaly of 8.3% at diagnosis with an additional 35% developing GS during SA. GS occurred after 3 months-18 yr (median 3 yr) of SA treatment, were diagnosed after symptoms in 17.6%, were associated to steatosis, ultrasound biliary dilation, and biochemical cholestasis, in 25.6%, 12.8%, and 4% of patients, respectively. Ursodehoxicolic acid was administered after GS occurrence, causing their dissolution in 39% of patients after 3-48 months (median 12). Cholecystectomy was performed in 16.8%of patients in group 2. At multivariate analysis obesity, dyslipidemia, and SA treatment were independent predictors of GS onset, whereas gender and age were not.

CONCLUSIONS

GS are a frequent occurrence in acromegalic patients treated with SA, may occur at any time, but are seldom symptomatic or prompt acute surgery. Obesity and dyslipidemia appear to play a major role in the occurrence of GS in acromegalic patients on SA treatment.

Catalytic domain of MMP20 (Enamelysin) - the NMR structure of a new matrix metalloproteinase

The solution structure of the catalytic domain of MMP-20, a member of the matrix metalloproteinases family not yet structurally characterized, complexed with N-Isobutyl-N-(4-methoxyphenylsulfonyl)glycyl hydroxamic acid (NNGH), is here reported and compared with other MMPs-NNGH adducts. The backbone dynamic has been characterized as well. We have found that, despite the same fold and very high overall similarity, the present structure experiences specific structural and dynamical similarities with some MMPs and differences with others, around the catalytic cavity. The present solution structure, not only contributes to fill the gap of structural knowledge on human MMPs, but also provides further information to design more selective and efficient inhibitors for a specific member of this class of proteins.

A multi-biomarker analysis of DNA damage in automobile painters

The genotoxic effects associated with automobile painting were analyzed using a panel of biomarkers. Chromosomal aberrations (CAs), sister chromatid exchange (SCE), and micronuclei were evaluated in 25 car painters (12 smokers, 13 nonsmokers) working in different automobile paint-shops in Italy and in 37 control subjects. The controls were healthy blood donors (14 smokers, 23 non-smokers) that were matched with the experimental population for gender and age. Air samples were analyzed regularly at the work places, and elevated concentrations of benzene and toluene were detected consistently. The exposed group had higher frequencies of CAs (both chromosome- and chromatid-type), micronuclei, and SCE (P < 0.5 - P < 0.001). Furthermore, exposed and control subjects were also genotyped for GSTM1 and GSTT1 polymorphism. No significant associations were detected between the biomarker responses and either the GSTM1 or GSTT1 genotype of the subjects, but the small sample size does not allow definite conclusions on the relationship between the genetic polymorphism and the biomarkers. The results indicate that automobile painters have increased levels of clastogenic and possible aneugenic damage and that smoking may be a confounding factor for the responses.

Treatment of acromegaly with SS analogues: should GH and IGF-I target levels be lowered to assert a tight control of the disease?

BACKGROUND

in acromegaly, the criteria for the cure of the disease after neurosurgery have become tighter and tighter. In contrast, the evaluation of control of disease activity during medical treatment is based upon the normalisation of IGF-I levels and epidemiological criteria, i.e. lessening GH (assessed by RIA) to levels reported to normalise increased mortality. The aim of this study was to evaluate GH and IGF-I suppression during prolonged SS analogues (SA) treatment. The concordance between "safe" GH and normalised IGF-I levels during SA was also assessed, according to gender and gonadal status.

DESIGN

multicentre, retrospective. Patients. GH/IGF-I levels were evaluated in 207 acromegalic patients (132 females, aged 20-85 yr) during a prolonged treatment (longer than 12 months) with individually tailored doses of depot SA( lanreotide or octreotide-LAR in 97 and 110 patients, respectively). Final IGF-I levels were transformed in z-scores using data collected in a large cohort of normal subjects of 3 different age groups (20-40 yr old, 41-60 yr old, 61-80 yr old, n=160, 148, 115, respectively), that allowed to set up quartiles of normality (I = 3rd-25th percentile, II = 26th-50th, III = 51th-75th, IV = 76th-97th).

RESULTS

fifty-nine and 19.3% of patients achieved GH levels <2.5 and <1 microg/l, respectively. IGF-I were normalised (z-score between 2 and -2) in 58.4% of patients. The distribution of normal IGF-I values among quartiles was uneven: 7%, 19%, 25%, and 49% of values were distributed in the I, II, III, and IV quartile, respectively. The concordance between GH and IGF-I values was poor: 28.4% of patients attaining GH values <2.5 microg/l had still pathological IGF-I (even 12.5% of those with GH <1 microg/l), and 39.3% of those with GH levels still above the "safe" limit had "nor IGF-I. Although proportions of IGF-I normalisation were not different between males and females, the regression line obtained between GH and IGF-I z-score showed the same slope but with a significantly lower intercept in regularly cycling women than in males and in postmenopausal females. Thus for any GH value, cycling females had lower IGF-I than menopausal women and males, and their IGF-I normalisation could be achieved by higher GH values. By ROC analysis, the achievement of normal IGF-I was predicted by the GH value of 1.8 microg/l in males and 2.4 microg/l in females.

CONCLUSIONS

in acromegalic patients on SA treatment, GH and IGF-I levels are often not concordant. In addition to age, sex is to be taken into account in the evaluation of hormonal targets. A better refinement of GH and IGF-I targets to be reached while on treatment with SA is warranted.

Effects of the selective estrogen receptor modulator LY117018 on growth hormone secretion: In vitro studies

Sex steroids play an important role in modulating pulsatile growth hormone (GH) release, acting at both hypothalamic and pituitary level in both humans and experimental animals. Selective estrogen receptor modulators (SERMs) act as either estrogen receptor agonists or antagonists in a tissue-selective manner. In postmenopausal women, serum GH levels correlate positively with endogenous estradiol levels and insulin-like grwoth factor-I (IGF-I) is positively related to bone mineral density (BMD) at the spine and hip. The aim of the present study was to evaluate, for the first time, the direct effect of LY117018, an analog of raloxifene, on GH secretion from both human and rodent pituitary cells in vitro. Our results demonstrated that pharmacological concentrations of the raloxifene analog LY117018 can stimulate GH secretion through a direct action on the pituitary. LY117018 also showed an estrogen-like activity, inducing the proliferation of rat pituitary GH-secreting adenomatous cells (GH1).

Estroprogestinic pill normalizes IGF-I levels in acromegalic women

In some acromegalic patients medical treatment does not succeed in normalizing GH/IGF-I values. Data showing IGF-I suppression in acromegaly by estrogen and by tamoxifen use prompted us to reevaluate the effects of estroprogestins (EP) supplementation on GH/IGF-I levels in acromegalic women resistant or only partially sensitive to medical treatment. Eight active acromegalic women (30-52 yr, 4 with regular menses) entered a prospective open pilot study. Three of them, resistant to medical treatment, were off therapy; the remaining five, partially sensitive, maintained it at the maximally effective dosages throughout the study. Patients were treated with a triphasic pill (ethynil-estradiol 30-40-30 microg/day and desogestrel 50-70-100 mg/day) for 13 +/- 7 months. IGF-I levels fell from 512 (median, interquartile 436-657) microg/l to 282 (244-526) microg/l (p=0.0414); the decrease was observed in 6 patients (75%), and normal values were reached in 4 (50%). GH levels did not change [basal 7.6 (6.2-8.6) microg/l, final 7.6 (6.5-8.3) microg/l]. Effectiveness of treatment was not dependent on concomitant anti-GH treatment or gonadal status. In all patients IGF-I levels re-increased after EP withdrawal. This pilot study shows a marked IGF-I lowering effect of pill in acromegalic women, and warrants a prospective randomized study in patients resistant or partially sensitive to other medical treatments.

The Comet assay for the detection of DNA damage in Mus spretus from Doñana National Park

Doñana Park (Spain), a protected area in Europe, was affected by an environmental disaster in April 1998 that caused the spreading of acidic water and mud full of toxic metals from the Aznalcollar pyrite mine. In order to assess the contamination in the area and to monitor the possible biological effects of the toxic spill, a series of coordinated studies was performed utilizing several animal species living in that area. We performed genotoxicity monitoring using the Comet assay on peripheral blood leukocytes of the Algerian mouse (Mus spretus), a nonprotected rodent suitable as a bioindicator. The mice were sampled in different areas 6 months after the ecological disaster and again 1 year later. Our results showed that in 1998 all the areas examined were contaminated, as determined by an increase in the Comet assay parameters in the analyzed animals, whereas a significant decrease in the values of these parameters was observed in the 1999 samples, which were collected in a riverside area subject to tide flows. Thus, the Comet assay has proven to be an interesting and sensitive tool in studies of environmental genotoxicity.

Failure of radiotherapy in acromegaly

BACKGROUND

Recent data has raised skepticism regarding the long-term effectiveness of radiotherapy (RxT) in acromegaly and its role as an ancillary tool to neurosurgery (Tx).

PATIENTS

We evaluated 72 acromegalic patients previously submitted to RxT. Data were discarded in 23 patients, who were lost to follow-up, operated on after RxT or irradiated with techniques different from external conventional fractionated RxT. Among the remaining 49 (five with mixed GH-prolactin adenoma), 34 were irradiated after surgical failure and 15 as primary treatment. A second cycle of RxT was administered in two.

RESULTS

(i) GH/IGF-I. After a median follow-up of 14 years (range 3-41), normal age-matched IGF-I levels were reached in eight patients (16%) after 10 years, and GH levels <2.5 microg/l in six (12%) after 9 years. The rate of persistently pathological hormonal levels was still 90% at 25 years. All patients with GH/IGF-I normalization had undergone irradiation without any antisecretory drug. Neither basal GH nor tumor size affected the outcome of RxT. In three patients (6%) a relapse/worsening occurred. (ii) Tumor size. Tumor shrank after 8.5 years in 24 patients (49%), in nine of whom during GH-suppressive treatment. Tumor shrinkage was not predictive of hormonal normalization. (iii) Side-effects. Hypopituitarism was diagnosed in four patients (selective in three and global in one) and GH deficiency in one. Three patients had neurological side-effects and meningioma was shown in two patients.

CONCLUSION

RxT is unable to cure acromegaly, because it seldom achieves hormonal normalization even after a very prolonged follow-up. Concomitant antisecretory treatment seems to counteract its effects. RxT can still play a role in those patients with large tumor remnants, because of its capacity to shrink tumor size.

Strong antioxidant activity of ellagic acid in mammalian cells in vitro revealed by the comet assay

Oxidative stress due to oxygen and various radical species is associated with the induction of DNA single- and double-strand breaks and is considered to be a first step in several human degenerative diseases, cancer and ageing. Naturally occurring antioxidants are being extensively analysed for their ability to protect DNA against such injury. We studied three naturally occuring compounds, Ascorbic Acid, Melatonin and Ellagic acid, for their ability to modulate DNA damage produced by two strong radical oxygen inducers (H2O2 and Bleomycin) in cultured CHO cells. The alkaline Comet assay was used to measure DNA damage and a cytofluorimetric analysis was performed to reveal the intracellular oxidative species. The data showed a marked reduction of H2O2- and Bleomycin-induced DNA damage exerted by Ellagic Acid. On the contrary Ascorbic acid and Melatonin appeared to induce a slight increase in DNA damage per se. In combined treatments, they caused a slight reduction of H2O2-induced damage, but they did not efficiently modulate the Bleomycin-induced one. The Dichlorofluorescein diacetate (DCFH-DA) cytofluorimetric test confirmed the strong scavenging action exerted by Ellagic Acid.

Differential inhibition of growth hormone secretion by analogs selective for somatostatin receptor subtypes 2 and 5 in human growth-hormone-secreting adenoma cells in vitro

Somatostatin (SRIH), a cyclic tetradecapeptide hormone originally isolated from mammalian hypothalamus, is a potent suppressor of pituitary growth hormone (GH) secretion. SRIH acts through a family of G-protein-coupled membrane receptors containing seven transmembrane domains. Five genes encoding distinct SRIH receptor (SSTR) subtypes have so far been cloned in human and other species and termed SSTR1-5. In human somatotrophe pituitary adenomas GH secretion is controlled by both SSTR2 and SSTR5. However, in clinical practice only somatostatin analogs selective for SSTR2 (octreotide and lanreotide) are available. This may explain why clinical and in vitro responses to these analogs in acromegaly are only partial. In this study, we investigated the inhibitory effect of two new SRIH analogs with high selectivity for SSTR2 (NC-4-28B) and SSTR5 (BIM-23268) and compared it to that of native somatostatin (SRIH-14) on a large number of GH-secreting adenomas obtained by transphenoidal neurosurgery. Tissues from 16 adenomas were enzymatically dispersed and plated in 24-well dishes at 50,000 cells/well. After 3 days, groups of three wells were incubated for 4 h with medium alone, SRIH-14 or analogs NC-4-28B or BIM-23268, at the concentrations of 0.01, 0.1 and 1 microM. Our results show that 9 out of 16 adenomas were responsive (GH suppression: 20-40% vs. control, p < 0.05) to SRIH. In this group only 4 adenomas showed similar responses to both selective analogs, with 2 nonresponders (expression of other SRIH receptor subtypes) and 2 responders (concomitant expression of SSTR2 and SSTR5) to both analogs. GH release was selectively inhibited by NC-4-28B in 3 adenomas and by BIM-23268 in the remaining 2 adenomas, suggesting predominant expression of SSTR2 and SSTR5, respectively. SRIH failed to inhibit GH release in 7 adenomas (43%). Interestingly, in that group a better inhibitory effect was obtained with BIM-23268 (5 out of 7 adenomas) than with NC-4-28B, suggesting expression of a few SSTR5 receptors only, or of both SSTR2 and SSTR5, respectively. We conclude that the availability of somatostatin analogs selective for SSTR5 will enhance the treatment potency and spectrum in acromegaly.

GH/IGF-I normalization and tumor shrinkage during long-term treatment of acromegaly by lanreotide

New depot somatostatin analogs such as lanreotide-slow release (LAN) represent a significant improvement in the medical treatment of acromegaly. Seventy-three consecutive acromegalic patients, treated by LAN, were evaluated in a retrospective monocentric study. Sixteen were excluded from further evaluation due to combined treatment with dopamine agonist drugs, early LAN withdrawal for persistence of headache, or gastrointestinal side-effects. Fifty-seven patients (aged 20-82 years, 16 males) were thus evaluated. Thirty-two patients had been previously treated by neurosurgery (Tx) and/or radiotherapy (Rx). After washout, LAN (30 mg) was administered im at 10-14-day intervals. Time intervals between injections were then individually tailored to normalize IGF-I levels. LAN was administered for 12 (6-36) [median (range)] months. GH and IGF-I levels decreased from 13 (7-20) [median (interquartile)] microg/l to 3.2 (1.7-6.2) microg/l (p<0.0001) and from 780 (596-1000) microg/l to 264 (180-530) microg/l (p<0.000001), respectively. Seven patients were resistant to treatment. Among the 50 sensitive patients, GH levels fell below 2.5 microg/l in 52% (and below 1 microg/l in 18%), IGF-I levels normalized in 72% and both results were obtained in 46%. IGF-I values normalized in 87% of patients treated every 14 days, in 100% every 21-28 days, in 69% every 10 days and in 22% every 7 days. No different control of GH/IGF-I hypersecretion was evidenced between patients previously treated or not by Tx and/or Rx. Patients with the lowest basal hormonal levels and those over 55 years showed greater responsiveness (both p<0.05). The maintenance of LAN schedule up to 18 months determined a further suppression (p=0.04 for IGF-I). A reduction of tumor size was shown in 60% of evaluated patients (6/10). HbA1c slightly increased in 42% of patients and gallstones were observed in 16%. LAN is a very effective tool in the treatment of acromegaly: its chronic administration normalizes GH/IGF-I levels in most patients, shrinks the tumor in a high percentage of patients and seems to control hormonal hypersecretion as primary treatment as well as neurosurgery.

Cabergoline-induced CSF rhinorrhea in patients with macroprolactinoma. Report of three cases

induces the macroprolactinoma shrinkage. Endoscopic transsphenoidal surgery offers a safe, minimally invasive and efficient management of this complication, which allows to regularly perform the following steps of the therapeutical strategy against the prolactinoma.

Lanreotide 60 mg, a longer-acting somatostatin analog: tumor shrinkage and hormonal normalization in acromegaly

BACKGROUND

Somatostatin analogues are nowadays the milestone in the medical treatment of acromegaly. We evaluated the effects of a new 60 mg longer-acting formulation of lanreotide (LAN60) on GH/IGF-I levels and tumor size.

PATIENTS

Twenty-one acromegalics entered a prospective monocentric open study. Eight were consecutive "de novo" patients (group I). Thirteen patients sensitive to SA (GH levels < 2.5 [mgr]g/l and/or IGF-I normalization on chronic LAN 30 mg (LAN30) treatment) were switched to LAN60 (group II).

PROTOCOL

LAN60 was administered IM for 6 cycles at 28 day intervals. In group I when GH/IGF-I remained pathological, the intervals were shortened to 21 days for the last three cycles.

CONTROLS

GH/IGF-I at the end of the 1st, 3rd and 6th cycle; MRI at the end of the study in all patients in group I bearing an adenoma.

RESULTS

Group I. GH (p = 0.00638, below 2.5 [mgr]g/l in two patients) and IGF-I (p = 0.0289, normalized in 5) significantly decreased. In one of two patients shortening the LAN60 schedule was more effective in suppressing GH/IGF-I. Group II. No change in GH and IGF-I levels was observed with the administration of LAN60, instead of LAN30. On LAN60 GH remained below 2.5 [mgr]g/l in 8/10 patients and IGF-I normal in 11/11 patients that had attained those values on LAN30. Tumor markedly shrank (23% to 64% vs basal), from 1400 (664-1680) mm3 to 520 (500-960) mm3 (median, interquartile, p = 0.0218) in all the 5 evaluable patients.

CONCLUSION

LAN60 is a very effective and longer-lasting formulation for the treatment of acromegaly. A closer administration schedule might achieve greater efficacy. Its effectiveness in shrinking tumor opens new perspectives in the therapy of acromegaly.

Evaluation of genotoxic and cytotoxic properties of pesticides employed in Italian agricultural practices

In a program coordinated by the Italian Ministry of Works, we tested in vitro four pesticides widely employed in a developed agricultural region of central Italy. The four commercial agents were chosen on the basis of their diffusion in agricultural practice, knowledge of their active principle(s), and scant availability of data concerning their toxic and genotoxic activity. The agents were Cirtoxin, Decis, Tramat Combi (TC), and Lasso Micromix (LM). All substances were tested in three in vitro systems: Chinese hamster ovary (CHO) cells, a metabolically competent hamster cell line (Chinese hamster epithelial liver; CHEL), and root tips of Vicia faba (VF). The cytotoxic and genotoxic end points challenged were micronuclei and root tip length (RTL) in VF and mitotic index (MI), proliferation index (PI), cell survival (CS), cell growth (CG), cell cycle length (CCL), sister chromatid exchanges, chromosomal aberrations, and single-cell gel electrophoresis, or comet assay, in CHEL and CHO cells. Tested doses ranged from the field dose up to 200x the field dose to take into account accumulation effects. On the whole, tested agents appear to induce genotoxic damage only at subtoxic or toxic doses, indicating a low clastogenic risk. MI, PI, CS, CG, RTL, and CCL appear to be the less sensitive end points, showing no effects in the presence of a clear positive response in some or all of the other tests. Using cytogenetic tests, we obtained positive results for TC and LM treatments in CHO but not in CHEL cells. These data could be accounted for by postulating a detoxifying activity exerted by this cell line. However, cytogenetic end points appear to be more sensitive than those referring to cytotoxicity.

From macroprolactinoma to concomitant ACTH-PRL hypersecretion with Cushing's disease

Multiple pituitary hormone hypersecretions have been already described, but the combination of PRL and ACTH excess is rare. This report deals with a 42-yr-old woman affected by macroprolactinoma (PRL 12,720 microg/l, huge tumor with extrasellar extension at imaging). After one year on dopaminergic treatment causing PRL normalization and tumor shrinkage, she developed hypercortisolism (UFC 1,000 microg/24 h, ACTH 200 ng/l). Cushing's disease was diagnosed. After neurosurgery (at immunocytochemistry mixed ACTH-PRL adenoma was shown) hypercortisolism remitted, whereas pathological hyperprolactinemia with tumor remnant in cavernous sinus persisted and hypopituitarism developed. The patient reported seems atypical for the following reasons: 1) the concomitant PRL and ACTH hypersecretions; 2) the clinical presentation with hypercortisolism following hyperprolactinemia; 3) the surgical cure of hypercortisolism with persisting hyperprolactinemia.

Phyllanthus orbicularis aqueous extract: cytotoxic, genotoxic, and antimutagenic effects in the CHO cell line

The present work evaluates the cytotoxic, genotoxic, and antimutagenic effects of Phyllanthus orbicularis (plant of genus Phyllantus) aqueous extract in Chinese hamster ovary (CHO) cells. P. orbicularis aqueous extracts are used in Cuban traditional medicine for their antiviral activity against Hepatitis B virus and A and B flu virus. The cytotoxicity of the extract was tested by means of colony-forming ability and growth-inhibition assays as well as by measuring the mitotic index. Apoptosis induction and cell-cycle kinetics were analyzed by cytofluorimetric methods. Chromosome aberration assays were performed to study the genotoxic and antimutagenic activity of the extract. Results show that doses of up to 100 microg/ml of the extract did not induce any cytotoxic effects. Cell survival and mitotic index decreased significantly at doses higher than 100 microg/ml as a function of dose as well as of treatment time. Moreover, continuous treatments of up to 18 h induced the appearance of a significant number of apoptotic cells. Following a 3-h exposure to a dose of 750 microg/ml, cells accumulated significantly in G(2)-M phase and remained blocked in G(1-) and G(2)-M phases after several posttreatments in fresh growth medium. The aqueous extract alone did not induce chromosome aberrations but, in combined treatment with H(2)O(2), significantly reduced H(2)O(2)-induced chromosome aberrations. Flow cytometric analysis of DCFH intracellular oxidation showed that the extract decreased the oxidizing power of H(2)O(2.) This ability could possibly explain the extract's antigenotoxic activity. Absence of cytotoxicity at the lower tested doses and the antimutagenic properties of the extract stimulate the interest in studying possible new pharmaceutical uses of P. orbicularis.

DNA strand methylation and sister chromatid exchanges in mammalian cells in vitro

Among other targets, DNA demethylating agents are known to affect the sister chromatid exchange (SCE) frequency in mammalian cells in vitro. The SCE increase appears to be maintained for many (10-16) cell cycles after the end of the pulse in a given cell population, unlike SCEs induced by DNA damaging agents. Yet, epigenetic changes (such as demethylation) would not be expected to affect SCE at all. In the present report we challenge the working hypothesis of a relation between SCEs and demethylation by comparing SCE induction during different rounds of replication when the parental strands were normally methylated or demethylated. Azacytidine (AZA), ethionine (ETH), mitomycin-C (MMC), UV-irradiation (UV) and hydrogen peroxide (H(2)O(2)) were tested for SCE induction in a Chinese hamster ovary cell line after a single pulse, one or two cell cycles before fixation. Whereas MMC, UV and H(2)O(2) induce SCE in both protocols, AZA and ETH show an effect on SCEs only if administered two cycles before fixation. Because two cell cycles are needed in order to achieve demethylation of the parental DNA strand, the data reported here support our working hypothesis that demethylation in the parental DNA strand, at the level of the replication fork (i.e., the region where SCEs are formed), is responsible for an increase in mistaken ligations of processed damage, eventually yielding an increase in SCEs.