Isolation and Characterization of NP-POL Nonapeptide for Possible Therapeutic Use in Parkinson's Disease.

Colostrum and milk are the initial mammalian nourishment and rich reservoir of essential nutrients for newborn development. Bioactive peptides isolated from natural sources, such as colostrum, serve as endogenous regulators and can be used as alternative therapeutic agents in the treatment of neurodegenerative diseases. One example is the previously unknown NP-POL nonapeptide isolated from Colostrinin. In the present study, we investigated a method of NP-POL nonapeptide isolation using Bio-Gel P2 molecular sieve chromatography. We showed the protective effect of NP-POL on 6-hydroxydopamine- (6-OHDA-) induced neurotoxicity using rat adrenal pheochromocytoma (PC12 Tet On) cells. Treatment of PC12 cells with NP-POL nonapeptide reduced 6-OHDA-induced apoptosis and caused transient phosphorylation of extracellular signal-regulated kinases (ERK 1/2), which were shown to promote cell survival. NP-POL nonapeptide also protected neuronal cells against oxidative injury induced by 6-OHDA. These results showed a potential use of NP-POL in the therapy of Parkinson's disease.

Investigation of amyloid formation inhibition of chemically and biogenically from Citrus aurantium L. blossoms and Rose damascena oils of gold nanoparticles: Toxicity evaluation in rat pheochromocytoma PC12 cells.

Fibrillation inhibition effects of chemically and biogenically gold nanoparticles (GNPs) were investigated in vitro using human insulin as a model for fibrillation of protein. This inspection was followed using the Congo red assay, thioflavin T fluorescence measurements, transmission electron microscopy, and evaluation of cytotoxicity effects on rat pheochromocytoma PC12 cells. Biogenic GNPs were synthesized using oil extracts of Citrus aurantium L. blossoms and Rose damascena blossoms as reducing and concomitant agents. Congo red assay showed development of fibril formation of insulin at acidic media at 60°C over a period of 48h. In these circumstances, transmission electron micrographs confirmed the progress of fibril state from globular chains to amyloid. However, the results of ThT fluorescence measurements indicated a concentration-dependent inhibiting effect of chemically synthesized GNPs on insulin fibrillation in vitro, simultaneously by conversion of the formed fibrils into amorphous aggregates. Furthermore, biogenic GNPs were found to more effectively inhibit the fibril formation, compared to chemically synthesized GNPs. Accordingly, just 0.05nmolL-1 of the biogenic GNPs showed similar inhibition property of chemically synthesized GNPs with a concentration of 10nmolL-1. Both types of GNPs diminished toxicity of insulin fibrils in rat pheochromocytoma PC12 cells viability.

Assessment of the potential activity of major dietary compounds as selective estrogen receptor modulators in two distinct cell models for proliferation and differentiation.

Estrogen receptors (ERs) α and ß are distributed in most tissues of women and men. ERs are bound by estradiol (E2), a natural hormone, and mediate the pleiotropic and tissue-specific effects of E2, such as proliferation of breast epithelial cells or protection and differentiation of neuronal cells. Numerous environmental molecules, called endocrine disrupting compounds, also interact with ERs. Phytoestrogens belong to this large family and are considered potent therapeutic molecules that act through their selective estrogen receptor modulator (SERM) activity. Using breast cancer cell lines as a model of estrogen-dependent proliferation and a stably ER-expressing PC12 cell line as a model of neuronal differentiating cells, we studied the SERM activity of major dietary compounds, such as apigenin, liquiritigenin, daidzein, genistein, coumestrol, resveratrol and zearalenone. The ability of these compounds to induce ER-transactivation and breast cancer cell proliferation and enhance Nerve Growth Factor (NGF) -induced neuritogenesis was assessed. Surprisingly, although all compounds were able to activate the ER through an estrogen responsive element reporter gene, they showed differential activity toward proliferation or differentiation. Apigenin and resveratrol showed a partial or no proliferative effect on breast cancer cells but fully contributed to the neuritogenesis effect of NGF. However, daidzein and zearalenone showed full effects on cellular proliferation but did not induce cellular differentiation. In summary, our results suggest that the therapeutic potential of phytoestrogens can diverge depending on the molecule and the phenotype considered. Hence, apigenin and resveratrol might be used in the development of therapeutics for breast cancer and brain diseases.

Mifepristone reduces insulin resistance in patient volunteers with adrenal incidentalomas that secrete low levels of cortisol: a pilot study.

BACKGROUND: Incidental adrenal masses are commonly detected during imaging for other pathologies. 10% of the elderly population has an 'adrenal incidentaloma', up to 20% of these show low-grade autonomous cortisol secretion and 60% of patients with autonomous cortisol secretion have insulin resistance. Cortisol excess is known to cause insulin resistance, an independent cardiovascular risk marker, however in patients with adrenal incidentalomas it is unknown whether their insulin resistance is secondary to the excess cortisol and therefore potentially reversible. In a proof of concept study we examined the short-term effects of glucocorticoid receptor (GR) antagonism in patients with an adrenal incidentaloma to determine whether their insulin resistance was reversible. METHODOLOGY/PRINCIPAL FINDINGS: In a prospective open-label pilot study, six individuals with adrenal incidentalomas and autonomous cortisol secretion were treated with mifepristone (a GR antagonist) 200 mg twice daily and studied for 4 weeks on a Clinical Research Facility. Insulin resistance at four weeks was assessed by insulin resistance indices, lnHOMA-IR and lnMatsuda, and AUC insulin during a 2-hour glucose tolerance test. Biochemical evidence of GR blockade was shown in all individuals and across the group there was a significant reduction in insulin resistance: lnHOMA-IR (1.0vs0.6; p = 0.03), lnHOMA-%beta (4.8vs4.3; p = 0.03) and lnMatsuda (1.2vs1.6; p = 0.03). Five out of six individuals showed a reduction in insulin AUC >7237 pmol/l.min, and in two patients this showed a clinically significant cardiovascular benefit (as defined by the Helsinki heart study). CONCLUSIONS: Short-term GR antagonism is sufficient to reduce insulin resistance in some individuals with adrenal incidentalomas and mild cortisol excess. Further assessment is required to assess if the responses may be used to stratify therapy as adrenal incidentalomas may be a common remediable cause of increased cardiovascular risk. TRIAL REGISTRATION: ClinicalTrials.gov NCT00721201.

Identification of coffee components that stimulate dopamine release from pheochromocytoma cells (PC-12).

Coffee and caffeine are known to affect the limbic system, but data on the influence of coffee and coffee constituents on neurotransmitter release is limited. We investigated dopamine release and Ca(2+)-mobilization in pheochromocytoma cells (PC-12 cells) after stimulation with two lyophilized coffee beverages prepared from either Coffea arabica (AR) or Coffea canephora var. robusta (RB) beans and constituents thereof. Both coffee lyophilizates showed effects in dilutions between 1:100 and 1:10,000. To identify the active coffee compound, coffee constituents were tested in beverage and plasma representative concentrations. Caffeine, trigonelline, N-methylpyridinium, chlorogenic acid, catechol, pyrogallol and 5-hydroxytryptamides increased calcium signaling and dopamine release, although with different efficacies. While N-methylpyridinium stimulated the Ca(2+)-mobilization most potently (EC(200): 0.14±0.29µM), treatment of the cells with pyrogallol (EC(200): 48±14nM) or 5-hydroxytryptamides (EC(200): 10±3nM) lead to the most pronounced effect on dopamine release. In contrast, no effect was seen for the reconstituted biomimetic mixture. We therefore conclude that each of the coffee constituents tested stimulated the dopamine release in PC-12 cells. Since no effect was found for their biomimetic mixture, we hypothesize other coffee constituents being responsible for the dopamine release demonstrated for AR and RB coffee brews.

Long-term results of a prospective, randomized trial comparing retroperitoneoscopic partial versus total adrenalectomy for aldosterone producing adenoma.

PURPOSE: The indication for laparoscopic total or partial adrenalectomy in patients with aldosterone producing adrenal adenoma remains controversial. We compared retroperitoneoscopic partial and total adrenalectomy for aldosterone producing adrenal adenoma in a prospective, randomized, multicenter trial. MATERIALS AND METHODS: Patients with aldosterone producing adrenal adenoma were randomized to retroperitoneoscopic partial or total adrenalectomy. Patient characteristics, surgical data, complications and postoperative clinical results were analyzed statistically. RESULTS: From July 2000 to March 2004, 212 patients were enrolled in this study, including 108 and 104 who underwent total and partial adrenalectomy, respectively. The 2 groups were comparable in patient age, gender, body mass index and tumor site. Mean followup was 96 months in each group. No conversion to open surgery was needed and no major complications developed. Partial adrenalectomy required a shorter operative time than total adrenalectomy but this did not attain statistical significance. Intraoperative blood loss in the partial adrenalectomy group was significant higher than in the total adrenalectomy group (p <0.05) but no patient needed blood transfusion. All patients in each group showed improvement in hypertension, and in all plasma renin activity and aldosterone returned to normal after surgery. No patient required potassium supplements postoperatively. In the total and partial adrenalectomy groups 32 (29.6%) and 29 patients (27.9%), respectively, were prescribed a decreased dose of or fewer antihypertensive medicines at final followup. CONCLUSIONS: Retroperitoneoscopic partial adrenalectomy is technically safe. It has therapeutic results similar to those of total adrenalectomy in patients with primary aldosteronism due to aldosteronoma.

Increased uptake of [¹²³I]meta-iodobenzylguanidine, [¹8F]fluorodopamine, and [³H]norepinephrine in mouse pheochromocytoma cells and tumors after treatment with the histone deacetylase inhibitors.

[¹³¹I]meta-iodobenzylguanidine ([¹³¹I]MIBG) is the most commonly used treatment for metastatic pheochromocytoma and paraganglioma. It enters the chromaffin cells via the membrane norepinephrine transporter; however, its success has been modest. We studied the ability of histone deacetylase (HDAC) inhibitors to enhance [¹²³I]MIBG uptake by tumors in a mouse metastatic pheochromocytoma model. HDAC inhibitors are known to arrest growth, induce differentiation and apoptosis in various cancer cells, and further inhibit tumor growth. We report the in vitro and in vivo effects of two HDAC inhibitors, romidepsin and trichostatin A, on the uptake of [(3)H]norepinephrine, [¹²³I]MIBG, and [(18)F]fluorodopamine in a mouse model of metastatic pheochromocytoma. The effects of both inhibitors on norepinephrine transporter activity were assessed in mouse pheochromocytoma (MPC) cells by using the transporter-blocking agent desipramine and the vesicular-blocking agent reserpine. HDAC inhibitors increased [(3)H]norepinephrine, [¹²³I]MIBG, and [(18)F]fluorodopamine uptake through the norepinephrine transporter in MPC cells. In vivo, inhibitor treatment resulted in significantly increased uptake of [(18)F]fluorodopamine positron emission tomography (PET) in pheochromocytoma liver metastases (19.1 ± 3.2% injected dose per gram of tumor (%ID/g) compared to liver metastases in pretreatment scans 5.9 ± 0.6%; P<0.001). Biodistribution analysis after inhibitors treatment confirmed the PET results. The uptake of [(123)I]MIBG was significantly increased in liver metastases 9.5 ± 1.1% compared to 3.19 ± 0.4% in untreated control liver metastases (P<0.05). We found that HDAC inhibitors caused an increase in the amount of norepinephrine transporter expressed in tumors. HDAC inhibitors may enhance the therapeutic efficacy of [(131)I]MIBG treatment in patients with advanced malignant pheochromocytoma and paraganglioma.

Triptolide induces apoptosis in human adrenal cancer NCI-H295 cells through a mitochondrial-dependent pathway.

Triptolide, the main active component obtained from Tripterygium wilfordii Hook. f, has been reported to present potent immunosuppressive and anti-inflammatory biological activities. It has been previously shown that due to the cytotoxicity of triptolide it has a limited use in the clinic. Although numerous studies have shown that triptolide induced apoptosis in many human cancer cells there is no report to show triptolide-induced apoptosis in human adrenal cancer cells. We treated the human adrenal cancer NCI-H295 cells with triptolide in vitro and investigated its cytotoxic effects. The cytotoxicity was examined and quantitated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay and the viability of inhibition and apoptosis was determined by flow cytometric assay, using propidium iodide (PI) staining for apoptosis. Flow cytometric assay also used for the determination of reactive oxygen species (ROS) production and the levels of mitochondrial membrane potential (ΔΨm), and the caspase-3 and -9 activation in NCI-H295 cells. Western blotting was used for examining the changes of apoptotic associated proteins. The results indicated that triptolide induced cytotoxicity (decreased the percentage of viable cells) and induced sub-G1 phase (apoptosis) occurring in NCI-H295 cells and those effects are dose-dependent. Results also showed that triptolide promoted the production of ROS and decreased the levels of ΔΨm in examined NCI-H295 cells. The results showed that triptolide promoted the levels of cytochrome c, Apaf-1, AIF, Endo G, caspase-9 and -3 which were analyzed by Western blotting. These results suggest that triptolide is able to induce apoptosis on NCI-H295 cells through the mitochondrial-dependent signal pathway.

Radiation dosimetry, pharmacokinetics, and safety of ultratrace Iobenguane I-131 in patients with malignant pheochromocytoma/paraganglioma or metastatic carcinoid.

This is a first of many phase 1 study of Ultratrace Iobenguane I-131 (Ultratrace 131I-MIBG; Molecular Insight Pharmaceuticals, Inc., Cambridge, MA). High-specific-activity Ultratrace 131I-MIBG may provide improved efficacy and tolerability over carrier-added 131I-MIBG. We investigated the pharmacokinetics (PK), radiation dosimetry, and clinical safety in 11 patients with confirmed pheochromocytoma/paraganglioma (Pheo) or carcinoid tumors. A single 5.0-mCi (185 MBq) injection of Ultratrace 131I-MIBG, supplemented with 185 microg of unlabeled MIBG to simulate the amount of MIBG anticipated in a therapeutic dose, was administered. Over 120 hours postdose, blood and urine were collected for PK, and sequential whole-body planar imaging was performed. Patients were followed for adverse events for 2 weeks. Ultratrace 131I-MIBG is rapidly cleared from the blood and excreted in urine (80.3% +/- 2.8% of dose at 120 hours). For a therapeutic administration of 500 mCi (18.5 GBq), our estimate of the projected dose is 1.4 Gy for marrow and 10.4 Gy for kidneys. Safety results showed 12 mild adverse events, all considered unrelated to study drug, in 8 of 11 patients. These findings support the further development of Ultratrace 131I-MIBG for the treatment of neuroendocrine tumors, such as metastatic Pheo and carcinoid.

May an altered hypothalamo-pituitary-adrenal axis contribute to cortical bone damage in primary hyperparathyroidism?

Cortisol secretion has been reported to be increased in primary hyperparathyroidism (PHPT). Our aim was to evaluate circulating and urinary cortisol levels and the relationships with biochemical and bone parameters in patients with PHPT at the time of diagnosis. We studied 180 consecutive patients with PHPT (mean age +/- SD 60.0 +/- 13.2 years; F/M 140/40, BMI 25.8 +/- 4.8 kg/m(2)) and 56 subjects with incidentally discovered adrenal adenoma who served as controls (age 56.2 +/- 12.8 years, F/M 40/16, BMI 25.7 +/- 3.9 kg/m(2)). Serum morning and midnight cortisol and urinary free cortisol were measured in both groups. In PHPT patients bone mineral density was measured at the lumbar spine, femur, and forearm. Serum morning cortisol and urinary cortisol were similar in PHPT patients and controls, whereas midnight cortisol was higher in PHPT patients (5.3 +/- 4.7 vs. 2.9 +/- 0.9 microg/dL, P = 0.001). In this group, midnight cortisol correlated positively with age (r = 0.27, P = 0.008) and negatively with forearm (r = -0.36, P = 0.003) and total-femur T score (r = -0.30, P = 0.02). Multivariate regression analysis, including age, calcium, parathyroid hormone (PTH), and midnight cortisol as independent variables and forearm T score as dependent variable, indicated that age (beta = -0.29, P < 0.0001), PTH (beta = -0.33, P < 0.0001), and midnight cortisol (beta = -0.14, P < 0.04) were independently associated with forearm T score. Our findings show increased midnight cortisol levels in patients with PHPT, indicating a subtle alteration of the hypothalamo-pituitary-adrenal axis dynamics that is unrelated to the degree of disease activity; further data are needed to demonstrate the supplementary effect of this subtle alteration to bone damage in this condition.

Torcetrapib induces aldosterone and cortisol production by an intracellular calcium-mediated mechanism independently of cholesteryl ester transfer protein inhibition.

ILLUMINATE (Investigation of Lipid Level Management to Understand its Impact in Atherosclerotic Events), the phase 3 morbidity and mortality trial of torcetrapib, a cholesteryl ester transfer protein (CETP) inhibitor, identified previously undescribed changes in plasma levels of potassium, sodium, bicarbonate, and aldosterone. A key question after this trial is whether the failure of torcetrapib was a result of CETP inhibition or of some other pharmacology of the molecule. The direct effects of torcetrapib and related molecules on adrenal steroid production were assessed in cell culture using the H295R as well as the newly developed HAC15 human adrenal carcinoma cell lines. Torcetrapib induced the synthesis of both aldosterone and cortisol in these two in vitro cell systems. Analysis of steroidogenic gene expression indicated that torcetrapib significantly induced the expression of CYP11B2 and CYP11B1, two enzymes in the last step of aldosterone and cortisol biosynthesis pathway, respectively. Transcription profiling indicated that torcetrapib and angiotensin II share overlapping pathways in regulating adrenal steroid biosynthesis. Hormone-induced steroid production is mainly mediated by two messengers, calcium and cAMP. An increase of intracellular calcium was observed after torcetrapib treatment, whereas cAMP was unchanged. Consistent with intracellular calcium being the key mediator of torcetrapib's effect in adrenal cells, calcium channel blockers completely blocked torcetrapib-induced corticoid release and calcium increase. A series of compounds structurally related to torcetrapib as well as structurally distinct compounds were profiled. The results indicate that the pressor and adrenal effects observed with torcetrapib and related molecules are independent of CETP inhibition.

Functional analysis of cultured neural cells for evaluating cold/cool- and hot/warm-natured Chinese herbs.

Recently, modern scientific research has been required to understand pharmacological basis of traditional Chinese medicine (TCM) theory based on the ancient clinical experience, and to investigate the molecular mechanisms of action of Chinese herbs. Here, 20 Chinese herbs, classified into 4 properties (hot, warm, cold and cool) of TCM, were analyzed for their ability to exhibit antioxidant action, to enhance glucose uptake by murine microglia N9 cells, and to influence neurotransmitter norepinephrine (NE) release from rat pheochromocytoma PC12 cells. We found a generally protective effect of both hot/warm-natured and cold/cool-natured herbs against H(2)O(2)-induced N9 cell death, partially by elevating superoxide dismutase (SOD) activity. Glucose uptake was elevated after treatment with some hot/warm-natured herbs. In addition, most herbs with hot/warm nature tended to stimulate NE release, while such stimulatory effect was not observed in the herbs with cold/cool nature. Two cold/cool-natured herbs, Rhizoma coptidis and Radix scutellariae, even significantly suppressed the release. These results suggest that the distinct abilities of Chinese herbs to regulate neural cell functions appear to be correlated with their natures identified in traditional TCM theory, and may be a useful guide for their utility in neural degenerative diseases.

An additional child case of an aldosterone-producing adenoma with an atypical presentation of peripheral paralysis due to hypokalemia.

Aldosterone-producing adenoma, which is characterized by hypertension, hypokalemia, and elevated aldosterone levels with suppressed plasma renin activity, is a rare condition during childhood and is also potentially curable. To the best of our knowledge, nearly 25 cases of childhood aldosterone-secreting adenoma have been reported in the literature to date. Here we describe a 13-yr-old girl with primary hyperaldosteronism secondary to aldosterone-secreting adenoma. The patient was admitted to our hospital with the neuromuscular complaints of muscle weakness and inability to walk due to hypokalemia. She had been misdiagnosed as having hypokalemic periodic paralysis 2 months before admission and her symptoms had radically improved with potassium supplementation. However, her blood pressure levels had increased and her symptoms reappeared 2 days prior to being observed during hospitalization in our institution. Laboratory examinations revealed hypokalemia (2.1 mEq/l), and increased serum aldosterone levels with suppressed plasma renin activity. Abdominal ultrasonography and abdominal magnetic resonance imaging revealed left adrenal mass. Laparoscopic adrenalectomy was performed and histopathological examinations showed benign adrenal adenoma. Serum aldosterone levels and blood pressure levels returned to normal after surgical intervention. This case demonstrates the importance of a systemic evaluation including blood pressure monitorization of children with hypokalemia as intermittent hypertension episodes may be seen; cases without hypertension may be misdiagnosed as rheumatological or neurological disorders such as hypokalemic periodic paralysis, as in our case.

A case of pheochromocytoma presenting as low back pain.

OBJECTIVE: This case report describes and discusses a patient with a pheochromocytoma who presented to a chiropractic office with low back pain. CLINICAL FEATURES: The patient is a 51-year-old woman who was self-referred to our chiropractic service with low back pain that appeared to be musculoskeletal in nature. Four days after chiropractic consultation, she collapsed in cardiogenic shock with signs of congestive heart failure, left ventricular dysfunction, and hypotension. Computed tomographic image of the abdomen revealed a right-sided adrenal mass that was confirmed via laboratory analysis to be a pheochromocytoma. INTERVENTION AND OUTCOME: The patient underwent laparoscopic adrenalectomy and made a full recovery. Her initial back symptoms resolved with tumor excision. CONCLUSION: Pheochromocytomas are rare catecholamine-producing tumors of the adrenal glands that can mimic musculoskeletal conditions such as low back pain. Chiropractic physicians should be aware of the various clinical presentations and, when pheochromocytoma is suspected, make prompt referral to medical providers for diagnostic evaluation and treatment.

Royal jelly-induced neurite outgrowth from rat pheochromocytoma PC12 cells requires integrin signal independent of activation of extracellular signal-regulated kinases.

We showed earlier that neurite outgrowth of rat pheochromocytoma PC12 cells was stimulated by royal jelly extract (PERJ) or its unique component, AMP N(1)-oxide, via adenosine A2a receptors. In this study, we found that stimulated neurite outgrowth occurred in medium supplemented with serum, but not in serum-free medium. The pentapeptide GRGDS, which includes the RGD sequence commonly shared by extracellular matrix (ECM) components, could attenuate the effect of serum, suggesting that integrin receptor signaling was essential for the neurite outgrowth induced by PERJ or AMP N(1)-oxide. PERJ or AMP N(1)-oxide also activated extracellular signal-regulated kinases 1 or 2 (ERK1/2); however, this activation was not associated with the neurite outgrowth. As it is known that Mn(2+) induces neurite outgrowth from PC12 cells and activates ERK1/2 through integrin signals and that activation of ERK1/2 is essential for Mn2+-induced neurite outgrowth, a difference in the mechanism between Mn(2+)-induced and PERJ- or AMP N(1)-oxide-induced neurite outgrowth is suggested. Furthermore, we demonstrated that PERJ contained no ECM component-like substances. These results demonstrate that AMP N(1)-oxide and its analogues were the only entities in PERJ with neurite outgrowth-inducing activity and that they required integrin signaling in addition to activation of A2a receptors to induce neurite outgrowth.

Malignant pheochromocytomas and paragangliomas: a phase II study of therapy with high-dose 131I-metaiodobenzylguanidine (131I-MIBG).

Thirty patients with malignant pheochromocytoma (PHEO) or paraganglioma (PGL) were treated with high-dose 131I-MIBG. Patients were 11-62 (mean 39) years old: 19 patients males and 11 females. Nineteen patients had PGL, three of which were multifocal. Six PGLs were nonsecretory. Eleven patients had PHEO. All 30 patients had prior surgery. Fourteen patients were refractory to prior radiation or chemotherapy before 131I-MIBG. Peripheral blood stem cells (PBSCs) were collected and cryopreserved. 131I-MIBG was synthesized on-site, by exchange-labeling 131I with 127I-MIBG in a solid-phase Cu2+-catalyzed exchange reaction. 131I-MIBG was infused over 2 h via a peripheral IV. Doses ranged from 557 mCi to 1185 mCi (7.4 mCi/kg to 18.75 mCi/kg). Median dose was 833 mCi (12.55 mCi/kg). Marrow hypoplasia commenced 3 weeks after 131I-MIBG therapy. After the first 131I-MIBG therapy, 19 patients required platelet transfusions; 19 received GCSF; 12 received epoeitin or RBCs. Four patients received a PBSC infusion. High-dose 131I-MIBG resulted in the following overall tumor responses in 30 patients: 4 sustained complete remissions (CRs); 15 sustained partial remissions (PRs); 1 sustained stable disease (SD); 5 progressive disease (PD); 5 initial PRs or SD but relapsed to PD. Twenty-three of the 30 patients remain alive; deaths were from PD (5), myelodysplasia (1), and unrelated cause (1). Overall predicted survival at 5 years is 75% (Kaplan Meier estimate). For patients with metastatic PHEO or PGL, who have good *I-MIBG uptake on diagnostic scanning, high-dose 131I-MIBG therapy was effective in producing a sustained CR, PR, or SD in 67% of patients, with tolerable toxicity.

Inhibition of adrenal cortical steroid formation by procaine is mediated by reduction of the cAMP-induced 3-hydroxy-3-methylglutaryl-coenzyme A reductase messenger ribonucleic acid levels.

Elevated glucocorticoid levels are associated with many diseases, including age-related depression, hypertension, Alzheimer's disease, and acquired immunodeficiency syndrome. Cortisol-lowering agents could provide useful complementary therapy for these disorders. We examined the effect of procaine and procaine in a pharmaceutical formulation on adrenal cortical steroid formation. Procaine inhibited dibutyryl cyclic AMP (dbcAMP)-induced corticosteroid synthesis by murine Y1 and human H295R adrenal cells in a dose-dependent manner without affecting basal steroid formation. Treatment of rats with the procaine-based formulation reduced circulating corticosterone levels. This steroidogenesis-inhibiting activity of procaine was not observed in Leydig cells, suggesting that the effect was specific to adrenocortical cells. In search of the mechanism underlying this inhibitory effect on cAMP-induced corticosteroidogenesis, procaine was found to affect neither the cAMP-dependent protein kinase activity nor key proteins involved in cholesterol transport into mitochondria, cytochrome P450 side chain cleavage enzyme expression, and enzymatic activities associated with cholesterol metabolism to final steroid products. However, procaine reduced in a dose-dependent manner the 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA) activity and the dbcAMP-induced HMG-CoA reductase mRNA levels by affecting mRNA stability. These data suggest that the inhibitory effect of procaine on cAMP-induced corticosteroid formation is due to the reduced synthesis of cholesterol. This modulatory effect of procaine on HMG-CoA reductase mRNA expression was also seen in dbcAMP-stimulated Hepa1-6 mouse liver hepatoma cells. Taken together, these results suggest that procaine may provide a pharmacological means for the control of hormone-induced HMG-CoA reductase mRNA expression and hypercortisolemia.

Twenty-four hour 17-hydroxyprogesterone response to adrenocorticotropine in adrenal incidentalomas: augmented response after adrenalectomy in two patients.

The current study aimed to investigate the midterm (24 hour) response of 17-hydroxyprogesterone (17-OHP) and dehydroepiandrosterone sulphate (DHEA-S) to synthetic high-dose adrenocorticotropin (ACTH) in adrenal incidentalomas (Al). Seventeen patients with Al and 40 age- and sex-matched controls received synthetic ACTH (tetracosactide, 1000 microg, IM). Plasma, 17-OHP and DHEA-S were collected in basal conditions and after 1, 4, 6, 8 and 24 hours. (HPA) axis was also evaluated using circadian serum cortisol, urinary free cortisol and over-night 2 mg dexamethasone suppression. Basal plasma 17-OHP levels did not differ among the groups. However, the increment in plasma 17-OHP in patients both in terms of peak [13.76 +/- 2.52, 4.77 +/- 0.30ng/ml, mean +/- S.E.M, p < 0.001] and area under the curve [190 +/- 46, 96.75 +/- 32 ng/ml/h, p < 0.001] were significantly higher than that of the controls. Stimulated 17OH-P levels never reached 9.1 ng/ml in controls. Sixty-five (11/17) % of the patients were found to have exaggerated response. Three of the patients were found to have subclinical Cushing's syndrome and interestingly, two augmented their 17-OHP response to ACTH after unilateral adrenalectomy and normalisation of their HPA axis. Basal DHEA-S levels of the patients were significantly lower [99.21 +/- 45, 230.18 +/- 34 microg/dl, p < 0.01] and stayed persistently lower than that of the controls. Evidence of a heterozygous 21 hydroxylase deficiency, as indicated by the exaggerated 17-OHP response to ACTH, has been widely reported in Al patients. However, to our knowledge to date there is no report on augmented 17-OHP response to ACTH after adrenalectomy. Possible reasons for the augmentation were discussed.

NID67, a small putative membrane protein, is preferentially induced by NGF in PC12 pheochromocytoma cells.

In an effort to identify genes involved in neuronal differentiation, we have used representational difference analysis (RDA) to clone cDNAs that are preferentially induced by nerve growth factor (NGF) vs. epidermal growth factor (EGF) in PC12 pheochromocytoma cells. We now report the cloning of a previously unknown primary response gene, NID67. In addition to a robust induction by NGF and FGF, both of which cause PC12 cells to differentiate, NID67 is strongly induced by forskolin, A23187 and ATP. EGF, TPA and KCl induce NID67 only weakly. NID67 mRNA is most abundant in heart, ovary and adrenal. Modest levels are present in most brain regions, testis, thyroid, thymus, pituitary, kidney and intestine; little NID67 is present in skeletal muscle and cerebellum. The NID67 cDNA contains a 180 bp open reading frame (ORF) that encodes a 60 amino acid protein. The central 29 amino acids are very hydrophobic and very likely comprise a transmembrane domain. Mouse and human NID67 cDNAs contain an ORF similar to NID67; the rat and human protein sequences are 85% identical whereas the rat and mouse sequences are 92% identical. In vitro transcription and translation reactions confirmed that the ORF we identified produces a 6000 Da protein product. Several small membrane proteins are similar to NID67; they contain a transmembrane domain and little more. All of these proteins participate in forming or regulating ion channels. NID67 may play a similar role in cellular physiology.

[(123)I]metaiodobenzylguanidine and [(111)In]octreotide uptake in begnign and malignant pheochromocytomas.

Selecting the appropriate approach for resection and follow-up of pheochromocytomas (PCCs) is highly dependent upon reliable localization and exclusion of multifocal, bilateral, or metastatic disease. Metaiodobenzylguanidine (MIBG) scintigraphy was developed for functional localization of catecholamine-secreting tissues. Somatostatin receptor imaging (SRI) has a high sensitivity for localizing head and neck paragangliomas, but studies of intraabdominal PCCs are rare. In this study we review our experience of [(123)I]MIBG and SRI, performed since 1983 and 1989, respectively, in the work-up of primary and recurrent PCCs. Scintigraphic results were correlated with catecholamine secretion, size and site, malignancy, associated tumor syndromes, and morphological features. [(123)I]MIBG scans were performed in a total of 75 patients, in 70 cases before resection of primary PCCs and in 5 cases because of recurrent disease. Ninety-one PCCs were resected. The overall detection rates were 83.3% and 89.8% for PCCs larger than 1.0 cm. Multifocal disease was detected in 4 patients with [(123)I]MIBG. [(123)I]MIBG uptake correlated with greater size of PCC (r = 0.33; P = 0.008) and greater concentration of plasma epinephrine (r = 0.32; P = 0.006). [(123)I]MIBG-negative PCCs (n = 14) had significantly (P = 0.01) smaller diameters than [(123I)]MIBG-positive tumors. Furthermore, [(123)I]MIBG uptake was significantly higher in unilateral (P = 0.02), benign (P = 0.02), sporadic (P = 0.02), intraadrenal (P = 0.02), and capsular invasive (P = 0.03) PCCs than in bilateral, malignant, MEN2A/2B-related, extraadrenal, and noninvasive PCCs, respectively. The detection rate of SRI was only 25% (8 of 32) for primary benign PCCs. In 14 patients metastases occurred, which were effectively visualized with [(123)I]MIBG in 8 of 14 cases. SRI was able to detect metastases in 7 of 8 cases, including 3 [(123)I]MIBG-negative metastatic cases. In addition, [(123)I]MIBG and SRI detected 2 recurrences. In conclusion, [(123)I]MIBG uptake is correlated with the size, epinephrine production, and site of PCCs. Its role in bilateral and MEN2A/2B-related PCCs seems limited. In cases of recurrent elevation of catecholamines, localization of metastases and/or recurrence should be attempted with [(123)I]MIBG scintigraphy. In suspicious metastatic PCCs, SRI might be considered to supplement [(123)I]MIBG scintigraphy.