Biomedical subjects

Richard A Feelders

Publications and source records attributed to Richard A Feelders.

16 recordsLinked to original sources

PubMed2025

Gut microbial and functional alterations lead to metagenomic signatures for midgut neuroendocrine tumor patients and for carcinoid syndrome.

Midgut neuroendocrine tumors (NET) derive from enterochromaffin cells, which have a close interrelationship with intestinal microbiota. Recently, we have utilized 16S rRNA sequencing to uncover that midgut NET patients have a depleted gut microbiome and a specific fecal microbial signature. This study aims to validate these findings and to further characterize the role of microbes and microbial metabolic pathways in midgut NET patients with and without carcinoid syndrome (CS). Fecal samples from 60 midgut NET patients and 20 household-matched controls were subjected to whole metagenome sequencing. The gut microbial community composition of midgut NET patients differed from that of controls, with 2 genera, 17 species and 9 microbial pathways showing differential abundance (P < 0.001). No differences in the microbial composition were observed between midgut NET patients with and without CS (P > 0.05). However, we did observe changes in inter-genus correlations of Bacteroides, Odoribacter, Parasutterella, Klebsiella, Ruminococcus and Proteobacteria when comparing these two patient groups. A signature of 16 microbial species (area under the receiver operating characteristics (AUROC) curve 0.892) or 18 microbial pathways (AUROC 0.909) accurately predicted the presence of a midgut NET. Furthermore, a microbial signature consisting of 14 functional microbial pathways distinguished CS patients from non-CS patients (AUROC 0.807). Thus, this study confirms that the gut microbiome of midgut NET patients is altered at the metagenomic level, which is not related to the presence of CS. A fecal microbial signature could constitute a novel biomarker for the diagnosis of midgut NET or CS.

Aged↗

PubMed2006

Potent inhibitory effects of type I interferons on human adrenocortical carcinoma cell growth.

CONTEXT: Adrenocortical carcinoma (ACC) is a rare tumor with a poor prognosis. Despite efforts to develop new therapeutic regimens for metastatic ACC, surgery remains the mainstay of treatment. Interferons are known to exert tumor-suppressive effects in several types of human cancer. DESIGN: We evaluated the tumor-suppressive effects of type I interferons (IFN)-alpha2b and IFNbeta on the H295 and SW13 human ACC cell lines. RESULTS: As determined by quantitative RT-PCR analysis and immunocytochemistry, H295 and SW13 cells expressed the active type I IFN receptor (IFNAR) mRNA and protein (IFNAR-1 and IFNAR-2c subunits). Both IFNalpha2b and IFNbeta1a significantly inhibited ACC cell growth in a dose-dependent manner, but the effect of IFNbeta1a (IC50 5 IU/ml, maximal inhibition 96% in H295; IC50 18 IU/ml, maximal inhibition 85% in SW13) was significantly more potent, compared with that of IFNalpha2b (IC50 57 IU/ml, maximal inhibition 35% in H295; IC50 221 IU/ml, maximal inhibition 60% in SW13). Whereas in H295 cells both IFNs induced apoptosis and accumulation of the cells in S phase, the antitumor mechanism in SW13 cells involved cell cycle arrest only. Inhibitors of caspase-3, caspase-8, and caspase-9 counteracted the apoptosis-inducing effect by IFNbeta1a in H295 cells. In H295 cells, IFNbeta1a, but not IFNalpha2b, also strongly suppressed the IGF-II mRNA expression, an important growth factor and hallmark in ACC. CONCLUSIONS: IFNbeta1a is much more potent than IFNalpha2b to suppress ACC cell proliferation in vitro by induction of apoptosis and cell cycle arrest. Further studies are required to evaluate the potency of IFNbeta1a to inhibit tumor growth in vivo.

Adrenal Cortex Neoplasms↗

PubMed2006

Octreotide exerts only acute, but no sustained, effects on MRI enhancement of liver metastases in carcinoid syndrome.

We have investigated the acute and sustained hemodynamic effects of octreotide on hepatic metastases of midgut carcinoids using contrast-enhanced dynamic magnetic resonance imaging (MRI). Seven patients with the carcinoid syndrome and metastasized midgut carcinoid tumors underwent functional dynamic multi-phase gadolinium-enhanced MRI of selected liver metastases at baseline and 60 min after the subcutaneous (s.c.) administration of 100 microg octreotide, and also after 3 months with three times daily (t.i.d.) 100 microg octreotide s.c. Baseline MRIs showed the typical aspect of carcinoid liver metastases with a very bright signal on the T2-weighted sequences and intense enhancement in the arterial phase after injection of gadolinium-diethylenetriaminepentaacetate. MRIs 60 min after the s.c. administration of 100 microg octreotide showed a 34.9 +/- 6.2% (mean +/- SD) reduction in relative enhancement in the selected liver metastases as compared to baseline. In 2 patients, however, there was no (significant) reduction in the relative enhancement in the selected liver metastases 60 min after the s.c. administration of 100 microg octreotide as compared to baseline. Only in 2 patients did the MRIs at 3 months show a decrease in relative enhancement in one of the selected liver metastases. At 3 months, with 100 microg octreotide s.c. t.i.d., there was no correlation between the change in relative enhancement on MRI and the change in 24-hour 5-HIAA excretion. There is thus only an acute effect of octreotide on the perfusion of liver metastases. This study further shows that contrast-enhanced dynamic MRI can be a very useful tool for studying hemodynamic effects of medical therapies on liver metastases in patients with metastatic midgut carcinoids.

Aged↗

PubMed2006

Somatostatin receptor imaging for neuroendocrine tumors.

Tumors and metastases that express the somatostatin receptor subtypes sst2 sst3 or sst5 can be visualized in vivo after injection of radiolabeled octapeptide somatostatin analogs, like (111)In-pentetreotide. (111)In-pentetreotide scintigraphy also allows for more accurate staging of the disease by demonstrating tumor sites, which were not shown by conventional imaging. (111)In-pentetreotide scintigraphy may also detect resectable tumors that would have remained unrecognized using conventional radiological imaging techniques; it may prevent surgery with curative intent in those patients whose tumors have metastasized to a greater extend than could be detected with conventional radiological imaging and it may be used to select patients for treatment with the currently available octapeptide somatostatin analogs or with tumor targeted radioactive treatment with radiolabelled somatostatin analogs. (111)In-pentetreotide scintigraphy has also been used to select patients with pituitary tumors for medical treatment with octapeptide analogs, but its clinical usefulness for this purpose seems to be limited. It further allows scar tissue to be differentiated from tumor recurrence after the pituitary surgery or radiotherapy. However, a large variety of lesions in and around the pituitary region also express somatostatin receptors and, therefore, can be visualized by (111)In-pentetreotide scintigraphy.

Adrenal Gland Neoplasms↗

PubMed2006

Prediction of mortality risk in the elderly.

PURPOSE: Ways to predict the risk of cardiovascular (CV) events or all-cause mortality have largely been derived from populations in which old and very old subjects were underrepresented. We set out to estimate the incremental prognostic utility of inflammation and atherosclerosis markers in the prediction of all-cause and CV mortality in elderly men. METHODS: In a prospective population-based cohort study, conventional CV risk factors were documented in 403 independently living elderly men. C-reactive protein (CRP) and interleukin (IL)-6 levels were measured. Carotid plaques were assessed by ultrasound. Analyses were performed with proportional hazards analyses, and bootstrapping was used for internal validation. Main outcome was CV and all-cause mortality occurring during 4 years of follow-up. RESULTS: Increasing tertiles of CRP, IL-6, and number of plaques were independently associated with all-cause and CV mortality. With information on age, carotid plaques, IL-6, and CRP yielded good discriminatory power for all-cause and CV mortality: area under the receiver operating characteristic curve (95% confidence interval), 0.76 (0.70-0.82) and 0.74 (0.68-0.80), respectively. Combined use of only IL-6 and plaque burden allowed identification of subjects with low and high mortality risk. The Framingham PROCAM and a Dutch Risk Function poorly predicted mortality risk, similar or worse than a model using age alone. CONCLUSION: In the old and very old, IL-6 and number of carotid plaques are powerful predictors of mortality risk in the years to come. Conventional risk scores seem to perform unsatisfactorily.

Aged↗

PubMed2006

Dopamine agonist therapy of clinically non-functioning pituitary macroadenomas. Is there a role for 123I-epidepride dopamine D2 receptor imaging?

OBJECTIVE: Clinically non-functioning pituitary adenomas (NFPAs) can express functional dopamine D2 receptors. Therapy with dopamine (DA) agonists may result in a NFPA size reduction. However, DA agonist-sensitive and -resistant NFPAs are clinically indistinguishable. We have studied the correlation between in vivo imaging of D2 receptors using (123)I-epidepride and the radiological response of NFPA to DA in 18 patients. METHODS: Patients were treated with either cabergoline (1-2 mg/week) or quinagolide (150-300 mug/day) for a mean period of 89.7 months (range, 34-187 months). RESULTS: Pituitary uptake of (123)I-epidepride varied from slight uptake classified as grade 0 to very high classified as grade 3. Grade 0 uptake was found in four patients; grade 1 in three; grade 2 in ten, and grade 3 in one. NFPA stabilization or shrinkage with DA agonist therapy showed no significant difference between grade 0, 1, and 2 tumors (mean tumor stabilization or shrinkage: 31, 30, and 36% respectively). However, when we considered a decrease in tumor size ranging from 0 to 20% as tumor stabilization and >20% decrease in tumor size as true shrinkage, one out of four NFPAs with grade 1 uptake, two out of three with grade 1 uptake, and eight out of ten with grade 2 uptake showed tumor shrinkage. CONCLUSION: In conclusion, there is limited clinical usefulness of dopamine D2 receptor imaging for predicting the clinical efficacy of DA agonist in selected patients with NFPAs. DA agonist therapy in NFPAs can result in tumor stabilization and shrinkage.

Adenoma↗

PubMed2006

Effects of therapy with [177Lu-DOTA0, Tyr3]octreotate in patients with paraganglioma, meningioma, small cell lung carcinoma, and melanoma.

UNLABELLED: Therapy using the radiolabeled somatostatin analog [177Lu-DOTA0,Tyr3]octreotate (177Lu-octreotate) (DOTA is 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid) has been used primarily in gastroenteropancreatic neuroendocrine tumors. Here we present the effects of this therapy in a small number of patients with metastasized or inoperable paragangliomas, meningiomas, small cell lung carcinomas (SCLCs), and melanomas. METHODS: Twelve patients with paraganglioma, 5 with meningioma, 3 with SCLC, and 2 with eye melanoma were treated. Three meningiomas were very large and exophytic and all standard treatments had failed. Patients with melanoma had rapidly progressive disease (PD). The intended cumulative dose of 177Lu-octreotate was 22.2-29.6 GBq. Effects of the treatment on tumor size were evaluated using the Southwest Oncology Group criteria. RESULTS: Two of 4 patients with progressive paraganglioma had tumor regression and 1 had stable disease (SD). Of 5 patients with stable paraganglioma, 2 had SD, 2 had PD, and in 1 patient treatment outcome could not be determined. Paraganglioma was stable in 3 patients in whom the disease status at the beginning of therapy was unknown. One of 4 patients with progressive meningioma had SD and 3 patients had PD. One patient with stable meningioma at the beginning of therapy had SD. All patients with SCLC or melanoma died within 5 mo after starting therapy because of tumor progression. Although not statistically significant, a positive trend was found between high uptake on pretherapy somatostatin receptor scintigraphy and treatment outcome. CONCLUSION: 177Lu-octreotate can be effective in patients with paraganglioma and meningioma. Response rates are lower than those in patients with gastroenteropancreatic neuroendocrine tumors. Most meningiomas were very large. Further studies are needed to confirm the treatment outcome because of the limited number of patients. 177Lu-octreotate did not have antitumor effects in patients with small lung carcinoma and melanoma.

Adult↗

PubMed2005

Thyroid hormone concentrations, disease, physical function, and mortality in elderly men.

CONTEXT: Physiological changes in thyroid hormone concentrations might be related to changes in the overall physical function in the elderly. OBJECTIVE: We determined to what extent thyroid hormone concentrations are related to physical function and mortality in elderly men. DESIGN: A longitudinal population study (the Zoetermeer study) was conducted. Mortality was registered in the subsequent 4 yr. PARTICIPANTS: Four hundred three independently and ambulatory living men (aged 73-94 yr) participated. MAIN OUTCOME MEASURES: The study examined the association between serum thyroid hormones and parameters of physical function as well as the association with mortality. METHODS: TSH, free T4 (FT4) total T4, T3, rT3, and T4-binding globulin were measured. Physical function was estimated by the number of problems in activities of daily living, a measure of physical performance score (PPS), leg extensor strength and grip strength, bone density, and body composition. RESULTS: Serum rT3 increased significantly with age and the presence of disease. Sixty-three men met the biochemical criteria for the low T3 syndrome (decreased serum T3 and increased serum rT3). This was associated with a lower PPS, independent of disease. Furthermore, higher serum FT4 (within the normal range of healthy adults) and rT3 (above the normal range of healthy adults) were related with a lower grip strength and PPS, independent of age and disease. Isolated low T3 was associated with a better PPS and a higher lean body mass. Low FT4 was related to a decreased risk of 4-yr mortality. CONCLUSIONS: In a population of independently living elderly men, higher FT4 and rT3 concentrations are associated with a lower physical function. High serum rT3 may result from a decreased peripheral metabolism of thyroid hormones due to the aging process itself and/or disease and may reflect a catabolic state. Low serum FT4 is associated with a better 4-yr survival; this may reflect an adaptive mechanism to prevent excessive catabolism.

Activities of Daily Living↗

PubMed2005

Expression of the human glucocorticoid receptor splice variants alpha, beta, and P in peripheral blood mononuclear leukocytes in healthy controls and in patients with hyper- and hypocortisolism.

CONTEXT: The effects of cortisol are mediated by the alpha-isoform of the glucocorticoid receptor (GR). GR-alpha levels and activity are modulated by alternative splicing of the common pre-mRNA into mRNAs for the GR-beta and GR-P isoforms. OBJECTIVE: The objective of this study was to investigate whether chronic hypercortisolism, chronic hypocortisolism, or acute, relative hypocortisolism influences the expression levels of the GR splice variants in mononuclear leukocytes. DESIGN: This was a case-control study. SETTING: The study was performed at a university hospital. PARTICIPANTS: Eighteen patients with Cushing's syndrome, five patients with hypocortisolemia, seven patients undergoing metyrapone testing, and 14 controls were studied. MAIN OUTCOME MEASURES: The main outcome measures were mRNA levels, GR affinity, and number per cell. RESULTS: All three GR mRNA isoforms were detected in participants from all groups at relative levels of alpha/P/beta = 1:0.25:0.001. There was a significant correlation between the expression levels of the three splice variants and between the mRNA levels and the number of receptors per cell. The GR in Cushing patients had an increased Kd (P < 0.05) preoperatively. GR number was not significantly different. Postoperatively, the Kd decreased. GR-beta mRNA expression was increased compared with controls (P < 0.05) and was decreased after surgery (P < 0.05). In patients with chronic hypocortisolism, GR-alpha mRNA expression was increased, and receptor numbers were increased (P < 0.05), whereas GR affinity was normal. No changes were observed in patients undergoing a metyrapone test. CONCLUSIONS: Cushing's syndrome is accompanied by a reversible decrease in GR affinity, possibly related to an increased GR-beta expression, which may be a compensatory mechanism to GC excess. In chronic hypocortisolism, adaptive changes in GR status seem to occur at the level of GR number.

Adult↗

PubMed2005

Radiolabeled somatostatin analog [177Lu-DOTA0,Tyr3]octreotate in patients with endocrine gastroenteropancreatic tumors.

PURPOSE: There are few treatment options for patients with metastasized or inoperable endocrine gastroenteropancreatic (GEP) tumors. Chemotherapy can be effective, but the response is usually less than 1 year. Here, we present the results of treatment with a radiolabeled somatostatin analog, [177Lu-DOTA0,Tyr3]octreotate (177Lu-octreotate). PATIENTS AND METHODS: One hundred thirty-one patients with somatostatin receptor-positive tumors were treated with up to a cumulative dose of 600 to 800 mCi (22.2 to 29.6 GBq) of 177Lu-octreotate. RESULTS: One patient developed renal insufficiency, and another patient developed hepatorenal syndrome. Creatinine clearance did not change significantly in the other patients. WHO hematologic toxicity grade 3 or 4 occurred after less than 2% of the administrations. We observed complete remission in three patients (2%), partial remission in 32 patients (26%), minor response (tumor diameter decrease of 25% to 50%) in 24 patients (19%), stable disease (SD) in 44 patients (35%), and progressive disease (PD) in 22 patients (18%). Higher remission rates were positively correlated with high uptake on pretherapy somatostatin receptor imaging and a limited number of liver metastases, whereas PD was significantly more frequent in patients with a low performance score and extensive disease. Median time to progression in 103 patients who either had SD or tumor regression was more than 36 months. CONCLUSION: Treatment with 177Lu-octreotate results in tumor remission in a high percentage of patients with GEP tumors. Serious side effects are rare. The median time to progression compares favorably with chemotherapy. Results are better in patients with a limited tumor load. Therefore, early treatment, even in patients who have no PD, may be better.

Adenoma, Islet Cell↗

PubMed2005

Distinct functional properties of native somatostatin receptor subtype 5 compared with subtype 2 in the regulation of ACTH release by corticotroph tumor cells.

In a series of human corticotroph adenomas, we recently found predominant mRNA expression of somatostatin (SS) receptor subtype 5 (sst5). After 72 h, the multiligand SS analog SOM230, which has a very high sst5 binding affinity, but not Octreotide (OCT), significantly inhibited basal ACTH release. To further explore the role of sst5 in the regulation of ACTH release, we conducted additional studies with mouse AtT-20 cells. SOM230 showed a 7-fold higher ligand binding affinity and a 19-fold higher potency in stimulating guanosine 5'-O-(3-thiotriphosphate) binding in AtT-20 cell membranes compared with OCT. SOM230 potently suppressed CRH-induced ACTH release, which was not affected by 48-h dexamethasone (DEX) pretreatment. However, DEX attenuated the inhibitory effects of OCT on ACTH release, whereas it increased the inhibitory potency of BIM-23268, an sst5-specific analog, on ACTH release. Quantitative PCR analysis showed that DEX lowered sst(2A+2B) mRNA expression significantly after 24 and 48 h, whereas sst5 mRNA levels were not significantly affected by DEX treatment. Moreover, Scatchard analyses showed that DEX suppressed maximum binding capacity (B(max)) by 72% when 125I-Tyr3-labeled OCT was used as radioligand, whereas B(max) declined only by 17% when AtT-20 cells were treated with [125I-Tyr11]SS-14. These data suggest that the sst5 protein, compared with sst2, is more resistant to glucocorticoids. Finally, after SS analog preincubation, compared with OCT both SOM230 and BIM-23268 showed a significantly higher inhibitory effect on CRH-induced ACTH release. In conclusion, our data support the concept that the sst5 receptor might be a target for new therapeutic agents to treat Cushing's disease.

Adrenocorticotropic Hormone↗

PubMed2005

The somatostatin analogue SOM230, compared with octreotide, induces differential effects in several metabolic pathways in acromegalic patients.

OBJECTIVE: Recently, our first clinical study with the novel multiligand somatostatin (SRIF) analogue SOM230 in acromegalic patients showed that SOM230, due to its beneficial inhibitory effects on GH levels compared with octreotide (OCT), might increase the number of patients that can be biochemically controlled. Since SRIF analogues are also known to interact with other metabolic pathways, IGF-I, IGFBP-1, glucose and insulin concentrations on the control day (CD) and on treatment days following a single s.c. injection SOM230 100 and 250 microg, were compared to those following OCT 100 microg. DESIGN AND PATIENTS: Randomized, cross-over, double-blinded proof-of-concept trial in 12 patients with active acromegaly. RESULTS: Free IGF-I levels were suppressed after 24 h by OCT, SOM230 250 and 100 microg, whereas at 48 h only both SOM230 dosages still induced these inhibitory effects. Circulating IGFBP-1 levels (AUC; 0830-1430 h) compared with CD, increased sharply after OCT (from 48 to 237 microg/l/h; P < 0.001 vs. CD), while SOM230 250 and 100 microg elicited a lower and dose-dependent effect (163 and 90 microg/l/h, respectively, P < 0.05 vs. CD and OCT). Neither insulin nor GH levels showed statistically significant correlation with IGFBP-1 levels either after SOM230 or OCT. An early rise in glucose levels 1 h postinjection with SOM230 250 microg compared with OCT and CD was observed 8.3 +/- 0.8, 4.4 +/- 0.5 and 4.9 +/- 0.4 mmol/l, respectively: P < 0.05). SOM230 250 microg (19 +/- 4 vs. 46 +/- 3 mU/l on CD: P < 0.05), although clearly less potent than OCT (5.4 +/- 0.4 mU/l: P < 0.01 vs. CD), inhibited insulin release. Since these corresponding absolute insulin levels cannot entirely explain this hyperglycaemic effect of SOM230, other mechanisms seem involved in this glucose rise. If SOM230 would influence glucose homeostasis in peripheral target tissues of insulin action, expression of SS-receptors (sst) seems a logical necessity. In normal human liver tissues, analysed by quantitative polymerase chain reaction (PCR), the average sst1 mRNA expression level appeared significantly higher compared with sst2 (n = 6, relative copy number 161 +/- 46 vs. 57 +/- 6; P < 0.05). Fat tissue expressed both sst1 and sst2 mRNA, whereas in muscle only sst2 mRNA was found. CONCLUSION: Both dosages of SOM230 inhibit free IGF-I in a more sustained fashion compared to OCT, implying longer duration of action. The superior action of OCT compared with SOM230 in stimulating IGFBP-1 levels, suggests direct regulation of IGFBP-1 by SRIF analogues via sst2. Finally, expression of only sst1 and sst2 in target tissues of insulin action, might point towards additional modulatory effects by SOM230 on glucose homeostasis.

Acromegaly↗

PubMed2005

Limited predictive value of an acute test with subcutaneous octreotide for long-term IGF-I normalization with Sandostatin LAR in acromegaly.

OBJECTIVES: To study whether the growth hormone (GH) response after the subcutaneous administration 50 microg of octreotide (acute octreotide test) has any predictive value for long-term IGF-I normalization with Sandostatin LAR. DESIGN: Twenty four therapy-naive patients with active acromegaly were studied. RESULTS: > 75% GH decrease in the acute octreotide test predicted long-term IGF-I normalization with Sandostatin LAR in 8/11 (73%) of patients. 3/13 (23%) patients with < 75% GH decrease in the acute octreotide test were long-term biochemically controlled with Sandostatin LAR. Using the > 75% GH reduction criterion, the sensitivity and specificity of this test for predicting long-term normalization of serum IGF-I with Sandostatin LAR treatment were 73% and 77%, respectively (positive and negative predictive values: 73% and 77%, respectively). 6/8 (75%) patients with GH suppression to levels < 1.1 microg/l and 9/16 (56%) patients with GH suppression to levels < 2 microg/l in the acute octreotide test showed normalization of serum IGF-I with long-term Sandostatin LAR treatment. The sensitivity and specificity of GH suppression < 1.1 microg/l for predicting of the long-term normalization of serum IGF-I with Sandostatin LAR therapy were 55% and 85%, respectively (positive and negative predictive values: 75% and 69%, respectively). The sensitivity and specificity of GH suppression < 2 microg/l for predicting of the long-term normalization of serum IGF-I with Sandostatin LAR therapy were 82% and 46%, respectively (positive and negative predictive values: 56% and 75%, respectively). CONCLUSION: The acute octreotide is not recommended for clinical decision making with regard to long-term treatment using the long-acting somatostatin analog Sandostatin LAR in acromegaly.

Acromegaly↗

PubMed2004

Association of the ER22/23EK polymorphism in the glucocorticoid receptor gene with survival and C-reactive protein levels in elderly men.

PURPOSE: We recently demonstrated that a polymorphism in codons 22 and 23 of the glucocorticoid receptor gene is associated with relative glucocorticoid resistance, greater insulin sensitivity, and lower total and low-density lipoprotein cholesterol levels. In the present study, we investigated whether the ER22/23EK polymorphism is associated with survival, cholesterol levels, and two predictors of mortality: serum C-reactive protein and interleukin 6 levels. METHODS: We studied 402 men (mean [+/- SD] age, 77.8 +/- 3.6 years). C-reactive protein was measured by a highly sensitive method using a latex-enhanced immunoephelometric assay. Interleukin 6 was determined by a commercially available immulite assay. RESULTS: After a follow-up of 4 years, 73 (19%) of 381 noncarriers died, while none of the 21 ER22/23EK carriers had died (P = 0.03). C-reactive protein levels were about 50% lower in ER22/23EK carriers (P = 0.01). There were no differences in interleukin 6 levels. CONCLUSION: Carriers of the ER22/23EK polymorphism have better survival than noncarriers, as well as lower C-reactive protein levels.

Aged↗

PubMed2004

A single-dose comparison of the acute effects between the new somatostatin analog SOM230 and octreotide in acromegalic patients.

Treatment with the somatostatin receptor (sst) subtype 2 predominant analogs octreotide and lanreotide induces clinical and biochemical cure in approximately 65% of acromegalic patients. GH-secreting pituitary adenomas, which are not controlled, also express sst(5). We compared the acute effects of octreotide and SOM230, a new somatostatin analog with high affinity for sst(1,2,3,5) on hormone release in acromegalic patients. In a single-dose, proof-of-concept study, 100 microg octreotide and 100 and 250 microg SOM230 were given s.c. to 12 patients with active acromegaly. Doses of 100 and 250 microg SOM230 dose-dependently suppressed GH levels from 2-8 h after administration (-38 +/- 7.7 vs. -61 +/- 6.7%, respectively; P < 0.01). A comparable suppression of GH levels by octreotide and 250 microg SOM230 was observed in eight patients (-65 +/- 7 vs. -72 +/- 7%, respectively). In three patients, the acute GH-lowering effect of 250 microg SOM230 was significantly superior to that of octreotide (-70 +/- 2 vs. -17 +/- 15%, respectively; P < 0.01). In one patient, the GH-lowering effect of octreotide was better than that of SOM230. Tolerability for SOM230 was good. Glucose levels were initially slightly elevated after octreotide and SOM230, compared with control day, whereas insulin levels were only significantly suppressed by octreotide. We conclude that SOM230 is an effective GH-lowering drug in acromegalic patients with the potential to increase the number of patients controlled during long-term medical treatment.

Acromegaly↗

PubMed2003

Luteinizing hormone (LH)-responsive Cushing's syndrome: the demonstration of LH receptor messenger ribonucleic acid in hyperplastic adrenal cells, which respond to chorionic gonadotropin and serotonin agonists in vitro.

In a substantial part of adrenal adenomas and hyperplasias from patients with Cushing's syndrome, cortisol production is controlled by the expression of aberrant hormone receptors on adrenocortical cells. We present in vivo and in vitro data of two patients with a LH-responsive Cushing's syndrome based on ACTH-independent bilateral adrenal hyperplasia. Patients 1 and 2 are women who presented with Cushing's syndrome and bilateral adrenal hyperplasia. Endocrine testing demonstrated absence of cortisol diurnal rhythm, insufficient cortisol suppression after 1 mg dexamethasone orally, and undetectable ACTH levels in both patients. Both patients were treated by laparoscopic biadrenalectomy. In in vivo testing, in patients 1 and 2, a profound cortisol rise was found after administration of GnRH [change in cortisol (Delta F), 118 and 106%, respectively], human CG (Delta F, 133 and 44%), LH (Delta F, 73 and 43%), ACTH (Delta F, 89 and 181%), and the 5-hydroxy-tryptamine receptor type 4 (5-HT(4)) agonists cisapride (Delta F, 141 and 148%) and metoclopramide (Delta F, 189 and 95%). In in vitro testing, adrenal cells from patient 2 responded, in a dose-dependent fashion, with cortisol production after exposure to human CG (Delta F, 45%), cisapride (Delta F, 68%), and metoclopramide (Delta F, 81%). ACTH induced cortisol production by cells from both patients (Delta F, 135 and 159%). In receptor studies, LH receptor mRNA was demonstrated in adrenal tissue of both patients but also in control adrenal tissue of two patients with persisting pituitary-dependent Cushing's syndrome treated by biadrenalectomy. In neither patient were mutations found in the ACTH receptor gene. LH-responsive Cushing's syndrome associated with bilateral adrenal hyperplasia may result from aberrant (or possibly increased) adrenal LH receptor expression. This variant is further characterized by adrenal responsiveness to 5-HT4 receptor agonists, possibly pointing to an interaction between LH and serotonin in the regulation of cortisol secretion. Despite the regulatory potential of LH and 5-HT4 receptor agonists on cortisol production in our patients, their adrenals seemed to be still sensitive to ACTH, both in vivo and in vitro.

Adrenal Glands↗