Depression, daily stressors and inflammatory responses to high-fat meals: when stress overrides healthier food choices.

Depression, stress and diet can all alter inflammation. This double-blind, randomized crossover study addressed the impact of daily stressors and a history of major depressive disorder (MDD) on inflammatory responses to high-fat meals. During two separate 9.5 h admissions, 58 healthy women (38 breast cancer survivors and 20 demographically similar controls), mean age 53.1 years, received either a high saturated fat meal or a high oleic sunflower oil meal. The Daily Inventory of Stressful Events assessed prior day stressors and the Structured Clinical Interview for DSM-IV evaluated MDD. As expected, for a woman with no prior day stressors, C-reactive protein (CRP), serum amyloid A (SAA), intercellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1) were higher following the saturated fat meal than the high oleic sunflower oil meal after controlling for pre-meal measures, age, trunk fat and physical activity. But if a woman had prior day stressors, these meal-related differences disappeared-because the stressors heightened CRP, SAA, sICAM-1 and sVCAM-1 responses to the sunflower oil meal, making it look more like the responses to the saturated fat meal. In addition, women with an MDD history had higher post-meal blood pressure responses than those without a similar history. These data show how recent stressors and an MDD history can reverberate through metabolic alterations, promoting inflammatory and atherogenic responses.

Disordered nocturnal prolactin regulation in women with breast cancer.

Mean 24-hr prolactin concentrations were determined in 25 female control subjects, 16 women with benign breast masses, and 23 subjects with breast cancer. This evaluation performed before breast surgery revealed significantly decreased (p less than 0.02) nocturnal (12 a.m. to 7 a.m.) prolactin concentrations in 12 postmenopausal breast cancer subjects that contrasted with significantly increased (p less than 0.05) nocturnal prolactin levels in five luteal-phase premenopausal women with breast cancers. Prolactin concentrations in patients with benign breast disease were not significantly different from control subjects. Two of the premenopausal breast cancer patients had marked preoperative elevations in their mean 24-hr prolactin levels, and they were two of the three subjects who have since expired. Nocturnal prolactin secretion was significantly decreased (p less than 0.03) in four premenopausal breast cancer patients when they were studied 1 year after surgery; however, it remained the same in the eight postmenopausal breast cancer patients similarly evaluated. Although disordered prolactin regulation has been found in these women with breast cancer, its role in the etiology and progression of human cancer is still uncertain.

Twenty-four-hour preoperative endocrine profiles in women with benign and malignant breast disease.

Mean 24-hr growth hormone, luteinizing hormone, follicle-stimulating hormone, estradiol, and progesterone concentrations determined preoperatively in 16 women with benign breast masses and 17 patients with breast cancer were similar to those levels found in 25 age- and weight-matched control subjects. Mean 24-hr testosterone levels, however, were significantly elevated in women with breast cancer evaluated in the luteal phase of their cycles and were normal in postmenopausal breast cancer women. In addition, serum thyroid-stimulating hormone, thyroxine, cholesterol, and triglyceride levels were normal in these subjects. Plasma cortisols and urinary 17-hydroxysteroid excretion tended to be higher in both the benign and malignant breast disease group and probably reflected preoperative anxiety. Hence, we have found normal concentrations of a variety of endocrine and other biochemical agents that can stimulate breast tissue growth and/or have been previously reported to be disordered in women with breast cancer.

Metabolic effects of long-acting somatostatin analogue (sandostatin) in type I diabetic patients on conventional therapy.

We evaluated the effectiveness of a more potent and longer-acting somatostatin analogue (SMS 201-995) as an adjunct to insulin therapy, in a double-blind placebo-controlled randomized study of 26 C-peptide-negative type I (insulin-dependent) diabetic patients (20 women, 6 men, aged 22-40 yr) on their conventional drug regimens for 12 wk. Eight patients received a low dose (10 micrograms) of the analogue, 9 received a high dose (50 micrograms) of the analogue, and 9 received placebo subcutaneously before breakfast and dinner. Twenty-four-hour serum glucose, free insulin, plasma growth hormone (GH), and glucagon profiles were obtained before and during treatment at 4-wk intervals. The mean age, duration of diabetes, daily insulin dose, and body weight were not significantly different among the groups. The mean weekly capillary blood glucose values and exogenous insulin requirements were not changed by the SMS 201-995 therapy. Mean glycosylated hemoglobin A1 levels were unchanged in both the analogue- and placebo-treated groups at wk 12. Basal and postprandial glucose, free insulin, GH, and glucagon profiles were not influenced by the SMS 201-995 therapy throughout the study. Nocturnal glucose turnover rates (D-[3-3H]glucose technique) remained unaltered by the analogue therapy. Dose-dependent gastrointestinal (GI) adverse effects (e.g., diarrhea) were documented in the analogue-treated patients. Visual acuity and fundic photomicrographs of our patients were not changed by the analogue therapy. In conclusion, the prominent adverse GI effects our patients experienced preclude the use of larger doses of the analogue that may be necessary to suppress GH and glucagon and improve glucose control in type I diabetic patients.

Stress-related changes in proinflammatory cytokine production in wounds.

BACKGROUND: Several recent studies have shown that stress markedly delays wound healing. This study assessed the relationship between psychological stress and the secretion of proinflammatory cytokines at an actual wound site, providing in vivo data on the development of local immune responses that are central in the early stages of wound repair. METHODS: To study the dynamics of inflammation, skin blisters were induced on the forearm of 36 women (mean age, 57 years) by suction. After the blister roofs were removed, a plastic template was taped to the arm, and wells were filled with 70% autologous serum in buffer. Specimens were aspirated from blister chamber wells 5 and 24 hours after wounding. RESULTS: Women with higher perceived stress scores demonstrated significantly lower levels of 2 key cytokines--interleukin 1alpha and interleukin 8--at wound sites. In addition, subjects who had low levels of both cytokines after 24 hours reported more stress and negative affect, and they had higher levels of salivary cortisol than those who had high cytokine levels. CONCLUSION: Consistent with the evidence that stress delays wound healing, these data suggest a possible mechanism: psychological stress has measurable effects on proinflammatory cytokine production in the local wound environment.

Pituitary tumors and hyperprolactinemia.

Hyperprolactinemia was demonstrated in eight of nine patients with clinical evidence of pituitary tumors without acromegaly or Cushing syndrome. Hourly sampling for 24 hours disclosed elevation of serum prolactin concentrations, whereas, measurable serum growth hormone levels were found rarely. Although eight of these patients were hypersecreting prolactin, only four of them were lactating. Prolactin secretion was characterized by moderate hourly fluctuations of serum levels and absence or blunting of the normal sleep-related augmentation of secretion. Patients with the highest serum prolactin concentrations tended to have the largest pituitary tumors, as indicated by pneumoencephalography. In two patients followed-up with serum prolactin determinations after treatment, a fall in serum prolactin concentrations correlated with clinical improvement. Future study will hopefully establish the value of serum prolactin determinations in following tumor growth before and after pituitary ablative therapy.

Expression and localization of prolactin messenger ribonucleic acid in the human immune system.

Pituitary PRL is involved in immunoregulation. Also, a PRL-like molecule is secreted by peripheral blood mononuclear cells. In this study, we examined tissues of the human immune system to evaluate if the PRL gene is expressed and to determine the location and type of cells involved in its synthesis. To evaluate the expression of PRL messenger RNA (mRNA) in normal and abnormal human lymphoid tissues, we used RT-PCR to generate a specific 276-bp product from normal human thymus, spleen, tonsil, lymph node, and lymphoid tumors. Restriction enzyme digestion confirmed that this PCR product was expressed PRL. Furthermore, we developed a specific and sensitive nonisotopic in situ hybridization technique for PRL mRNA, and cells containing PRL mRNA were found in each tissue of the human immune system. Also, PRL mRNA was widely distributed throughout neoplastic tissue from a thymoma and lymphomas where mitogenic and anti-apoptotic properties of PRL could be involved in tumor progression. PRL mRNA was localized in lymphocytes, epithelial cells, and vascular endothelial cells. The presence of PRL mRNA in vascular endothelium cells suggests other roles for PRL in these tissues in addition to immunomodulation. In conclusion, the presence of PRL mRNA in human lymphoid tissue implies that locally synthesized PRL may play a critical role in immunocompetence by providing an important regulatory signal to the microenvironment of human lymphoid organs.

Nonpuerperal lactation and normal prolactin regulation.

UNLABELLED: Prolactin secretion was evaluated in 11 consecutive patients referred with nonpuerperal lactation who did not have clinical evidence of pituitary tumors. Six patients had normal fasting prolactin (PRL) levels, 13.8 plus or minus 1.8 ng per ml (Group I), and the other 5 women had elevated basal serum PRL concentrations, 182 plus or minus 72 ng per ml (Group II). All Group II patients had amenorrhea; however, 5 of 6 Group I patients had menstrual periods. The 24-h mean serum PRL concentrations were 12.8 plus or minus 1.2 (SEM), 13.3 plus or minus 0.7, and 165 plus or minus 62 ng per ml for the controls and Group I and II, respectively. A pattern of intermittent PRL discharge during the day characterized each group; however, a normal sleep related increase in serum PRL concentration was absent in the Group II patients. Chlorpromazine produced greater than two-fold increases in serum PRL concentrations in the controls and Group I patients; however, this response was absent in Group II. L-Dopa produced appropriate suppression of serum PRL concentrations in the normals and both patient groups. Normal serum growth hormone, thyroxine, and plasma cortisol characterized each group. Serum estrogen and/or LH and FSH were decreased in 3 of 5 Group II patients; however, the serum concentrations of these hormones were normal in 5 of 6 Group I patients. Short term L-dopa therapy was effective in suppressing lactation in 3 of 5 Group II patients, and it also decreased lactation in the 4 treated Group I patients without significantly altering 24-h mean serum PRL concentrations in the latter group. CONCLUSION: hypothalamic-pituitary dysfunction was present in certain patients with nonpuerperal lactation who had elevated 24-h mean PRL concentrations and no PRL release following chlorpromazine and sleep. Frequently, however, nonpuerperal lactation is associated with normal prolactin secretion.

Twenty-four-hour prolactin profiles in normal and disease states: failure of thyroxine to modify prolactin secretion.

In order to assess the role of thyroid hormone on physiologically and pharmacologically induced prolactin (PRL) secretion, serum PRL concentrations were measured in 4 normal women and 4 women with various endocrinopathies before, and 4 to 6 days following, the ingestion of L-thyroxine (T4). A single 1.5 to 3.0 mg dose of oral T4 produced approximately a 2-fold increase in serum T4. Exogenous T4 did not significantly alter the mean concentration, or the pattern of PRL secretion during a 24-h interval in either normal individuals or 3 patients with galactorrhea. The lactating patients had elevated basal PRL levels and a blunted secretory response to intramuscular chlorpromazine; however, neither fasting PRL nor the peak response to chlorpromazine was altered by T4. L-Dopa suppression of serum PRL was not significantly influenced by T4 in these patients. In conclusion, PRL secretion remained unaltered after the administration of thyroxine in doses sufficient to produce approximately a 2-fold increase in serum T4. This challenges the concept that T4 and TRH are important physiologic regulators of PRL secretion.

Interleukin-1 beta and other cytokines stimulate adrenocorticotropin release from cultured pituitary cells of patients with Cushing's disease.

Interleukin-1 (IL-1) is a cytokine that is secreted by macrophages and monocytes which stimulates rodent hypothalamic CRH release and possibly pituitary ACTH secretion. We studied the effect of IL-1 beta and other cytokines (gamma-interferon, thymosin fraction-5, and granulocyte colony-stimulating factor) on ACTH release from corticotroph adenoma tissue obtained from two patients with Cushing's disease. IL-1 beta (0.001-10 mumol/L) increased ACTH release 3-fold. Thymosin fraction-5 (10 mumol/L), gamma-interferon (1 mumol/L), and granulocyte colony-stimulating factor (1 mumol/L) also stimulated ACTH release. These cultured cells secreted little or no GH, PRL, TSH, LH, and FSH, and their release was not stimulated by any cytokine. These results suggest that ACTH release in patients with Cushing's disease may be responsive to stimulation by various cytokines.

The natural history of idiopathic hyperprolactinemia.

Idiopathic hyperprolactinemia (IH) can be defined as the presence of elevated serum PRL levels in a patient in the absence of demonstrable pituitary or central nervous system disease and of any other recognized cause of increased PRL secretion. This study examined the long term clinical outcome of 41 patients (mean age, 26 yr) with IH followed for up to 11 yr (mean, 5.5 yr). Initial and final PRL levels were determined by RIA in the same laboratory. A correction factor was used to obviate periodic changes in the potency of the NIH standards used in the PRL assay, so that all results are expressed in terms of the original VLS no. 1 standard. The initial serum PRL levels ranged from 27.2-243 ng/ml, with a mean of 57 ng/ml. Only three patients had initial serum PRL levels greater than 100 ng/ml. All had a normal skull x-ray and/or brain computed tomographic scan during their initial visit. All 41 patients had galactorrhea and/or amenorrhea. Serum PRL levels remained the same, decreased, or returned to normal in 34 of 41 patients. The mean PRL level at the time of reevaluation was 35 ng/ml. Thirty-four percent of the patients had a normal serum PRL level. Only 17% of the patients had serum PRL levels that were significantly higher (greater than 50% of their original value). Six of 9 patients with an initial serum PRL level less than 40 ng/ml had normal levels. One patient developed a pituitary tumor (initial PRL, 150 ng/ml). All patients reevaluated with brain computed tomographic scans had normal pituitary size. No patient reported a worsening of signs or symptoms, and in many, improvement (n = 16) or complete resolution (n = 8) of the amenorrhea and/or galactorrhea occurred. Twenty-seven spontaneous or bromocriptine-induced normal pregnancies and deliveries occurred without development of a pituitary tumor. Therefore, our data clearly challenge the use of ablative pituitary therapy for IH and raises questions of the benefit of chronic medical therapy for this condition.

Localization of growth hormone messenger ribonucleic acid in the human immune system--a Clinical Research Center study.

GH is an immunomodulatory factor that can be synthesized and secreted by mononuclear leukocytes. To determine if GH can be produced by the human immune system, we assessed the presence of GH messenger RNA (mRNA) in both normal and abnormal human lymphoid tissues by RT-PCR and nonisotopic in situ mRNA hybridization. The predicted PCR product of 16lbp from human thymus, spleen, tonsil, lymph node, thymoma, and T and B cell lymphomas was similar to the product amplified from the human pituitary. Restriction enzyme digestion confirmed that complementary DNA generated using GH primers originated from GH mRNA. Furthermore, we performed in situ hybridization to localize the GH mRNA-positive cells. A hybridization signal for GH mRNA was found in all tissues examined. The distribution patterns of GH in normal lymphoid tissues suggested that GH can be produced by lymphocytes, as well as endothelial cells and other cell types. Also, GH mRNA-positive cells were distributed diffusely throughout T and B cell lymphomas and a thymoma. Our results demonstrate GH gene expression in normal and neoplastic human lymphoid tissues including nonlymphoid cells. This finding supports the hypothesis that the human immune system is an extrapituitary site of GH gene expression that may serve as an autocrine/paracrine factor in immunomodulation.

Characterization of a large molecular weight prolactin in women with idiopathic hyperprolactinemia and normal menses.

This study reports the presence of a large molecular sized PRL as the major form of circulating immunoactive PRL in five women with idiopathic hyperprolactinemia and normal menses. Gel filtration patterns of serum from these patients revealed 98-100% predominance of a 150,000- to 160,000-dalton PRL in contrast to the predominance of the 22,000-dalton species in other hyperprolactinemic patients. This 150,000- to 160,000-dalton PRL was immunologically similar to the 22,000-dalton PRL, and its size on gel filtration was not altered using denaturing conditions. With reduction of disulfide bonds, there was a shift of the peak I PRL to smaller mol wt peptides. In addition, studies of one woman with idiopathic hyperprolactinemia and normal menses revealed preservation of 98% peak I predominance during physiological and pharmacological perturbations of PRL secretion. Finally, assay of the bioactivity of the large molecular sized PRL in the Nb2 rat lymphoma line revealed diminished activity compared to the 22,000-dalton species. This latter finding may help explain the maintenance of normal menses and relative lack of clinical signs in patients with this form of hyperprolactinemia.

Persistence of large molecular weight prolactin secretion during pregnancy in women with macroprolactinemia and its presence in fetal cord blood.

Two hyperprolactinemic women with marked increases in circulating 150K PRL were studied from conception throughout pregnancy and delivery. The serum PRL increase during pregnancy in these women was considerably less than that in normal pregnant women (2- and 3.5-fold vs. 10- to 20-fold increases, respectively). The 150K PRL species persisted as the predominant circulating form of PRL throughout each trimester of pregnancy in these women. In contrast, the predominant form of PRL in serum from normal pregnant women was the 22K PRL form. Gel filtration analysis of the umbilical venous cord serum of infants of the macroprolactinemic women demonstrated excessive concentrations of 150K and 50K PRL compared to the molecular species of PRL in the cord serum of normal infants. Repeat analysis of the PRL species in one infant at age 3 yr continued to reveal excessive secretion of 150K PRL (11% vs. less than 6% in normals). These data suggest that genetic influences may be operative in determining PRL heterogeneity.

Growth hormone secretion by human peripheral blood mononuclear cells detected by an enzyme-linked immunoplaque assay.

In order to evaluate the secretion of GH from human peripheral blood mononuclear cells (PBMC) and its possible role as a modulator of lymphoproliferation, we have developed a hormonal enzyme-linked immunoplaque assay. This assay captures GH between a monoclonal and polyclonal antibody. This is followed by adding substrate and a horseradish peroxidase-conjugated antibody against the polyclonal antibody which produces violet colored plaques where GH has been secreted. This assay is sensitive, specific, highly reproducible, and can detect picogram quantities of GH. Using this assay we have detected GH secretion from approximately 1% of human PBMC under unstimulated conditions. Regression analysis showed a linear relationship between the number of cells plated and the number of GH plaques formed. Therefore, GH plaques were formed by single cells or its progeny and did not represent aggregation of secreting cells. Preincubation of PBMC with cycloheximide, a protein synthesis inhibitor, completely abolished the formation of GH plaques which suggests that the PBMC were responsible for the synthesis of the secreted GH. In addition, we have also observed that stimulation of human PBMC with T-cell mitogens, Concanavalin A and PHA and the cytokine IL-2 led to significant increases in GH plaque area and number whereas stimulation with LPS, a B cell mitogen, was ineffective. The PHA and IL-2 induced increase in plaque number suggests that they can recruit noncommitted lymphocytes to actively secrete GH which raises the possibility that this secreted GH may serve as a growth factor in T cell proliferation. We conclude that this immunoplaque assay may be useful in evaluating the secretion of other peptides from human immune cells.

Evidence that chorion-decidual prolactin release is calcium dependent.

The regulation of PRL release from chorion-decidual explants was evaluated in organ cultures. Agents previously shown to stimulate pituitary release in vitro (TRH, theophylline, estradiol, and vasoactive intestinal polypeptide) were all without effect on chorion-decidual PRL release. Media free of calcium, however, resulted in 44% decreased chorion-decidual PRL release. Conversely, 2.5 mM CaCl2 produced a 64% increase in PRL release (P less than 0.01). Also, calcium chelation with EGTA (0.125-1.0 mM) produced a dose-related decrease in chorion-decidual PRL release. This decrease was greatest at 1.0 mM (P less than 0.01), being 56% of control. In contrast, the calcium-calmodulin complex inhibitor trifluoperazine (10 micrometers) did not significantly alter chorion-decidual PRL release. These studies and previous report in the literature suggest that different control mechanisms govern pituitary and chorion-decidual PRL release; however, an exception appears to be a common role for calcium.

The dissociation of catecholamine and hypothalamic-pituitary-adrenal responses to daily stressors using dexamethasone.

The hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenal-medullary (SAM) systems are implicated in the human stress response. One characterization of these systems is that they are nonspecific in their response, but differ in activation threshold and time course. Additionally, they have been found to be affected commonly by strong metabolic stressors and infusions of CRH, and a hypothesis has been developed primarily from animal research that CRH stimulates both the HPA and SAM systems. To determine whether CRH was significantly involved in tonic as well as psychological stress-induced catecholamine levels in man, we infused 24 normal male undergraduate students with either saline (n = 12) or dexamethasone (DEX; n = 12) and evaluated their subsequent plasma levels of ACTH, cortisol, epinephrine (EPI), and not epinephrine (NEPI). DEX produced a dramatic decrease in ACTH and cortisol levels, but no significant changes in EPI or NEPI occurred over a 4-h sampling interval. After the administration of math and speech stressors in a controlled laboratory setting, DEX inhibited the ACTH and cortisol release that was noted in the saline group, but stress-induced increases in EPI and NEPI were comparable in both groups. Thus, our study suggests that there is a difference in the neural pathways for tonic and stress-induced stimulation of the SAM and HPA systems.

Delayed diagnosis of psychological erectile dysfunction because of the presence of macroprolactinemia.

Idiopathic hyperprolactinemia can be found in men with either normal or low serum testosterone (T) levels. The explanation for the differing effects on T of similar PRL levels has not been found. Macroprolactinemia, as a clinical entity, has been reported mostly in women. These macromolecules are biologically less active and/or are transported less easily across the capillary bed than the 22-kDa molecules. Therefore, women with elevated PRL levels retain normal menses and fertility. We studied six men, aged 28-53 yr (mean, 45 yr), in whom hyperprolactinemia was initially considered to be the cause of their erectile dysfunction. PRL levels ranged from 25-92 ng/mL (normal, 2-15 ng/mL), but T and gonadotropin levels were normal, suggesting that PRL was not disrupting gonadotropin and gonadal steroid function. The results of magnetic resonance imaging studies of the pituitary gland were normal. Separation by Sephadex G-100 column chromatography showed a predominance (85-90%) of big (60 kDa) and big big ( > 150 kDa) PRL, in contrast to the predominance of 22-kDa PRL in normal subjects. Nocturnal tumescence testing was normal, supporting the diagnosis of psychogenic impotence in these subjects, and potency returned after counseling. Hence, the biologically inactive macroprolactinemia did not cause any organic derangement in erectile function. It further obscured and delayed the appropriate diagnosis and treatment of these individuals.

Angiotensin II promotes prolactin release from normal human anterior pituitary cell cultures in a calcium-dependent manner.

Renin and angiotensin II (AII) have been demonstrated in the mammalian central nervous system, and AII has been found to promote PRL release in the rat and monkey. We added AII to monolayer cultures of human anterior pituitary cells and found significant PRL release by 30 min with concentrations of AII as low as 10(-10) M. This AII-induced PRL release was inhibited by the specific AII antagonist saralasin. AII-induced PRL release was a calcium-dependent process, since the calcium channel blockers verapamil and nifedipine as well as the calcium-calmodulin antagonist R2471 significantly inhibited AII-induced PRL release. Prostaglandins E2, A2, and F2 alpha also inhibited AII-induced PRL release. The significance of this latter observation is not clear, however, as indomethacin, an inhibitor of the cyclo-oxygenase prostaglandin metabolic pathway, had no effect on AII-induced PRL release. In light of recent immunohistochemical evidence of the presence of renin, angiotensinogen, and converting enzyme in human lactotrophs, our data support the concept that AII may be an important autocrine regulator of PRL secretion.

Cerebrospinal fluid prolactin: a reflection of abnormal prolactin secretion in patients with pituitary tumors.

Cerebrospinal fluid prolactin levels were determined in 33 patients with pituitary disease, 3 pregnant women at term and 30 control subjects. Prolactin which was immunologically similar to the human prolactin standard was detected by radioimmunoassay in the CSF of most of these subjects. Elevated serum and CSF PRL concentrations were found in three pregnant subjects and in twelve patients with putuitary tumors. Ten patients with pituitary tumors had serum PRL concentrations greater than their corresponding CSF PRL levels. A significant correlation was noted between the elevated serum and CSF prolactin levels in the twelve hyperprolactinemic patients which suggested that the CSF prolactin concentration was influenced by the serum PRL level. Two patients with pituitary tumor however, had CSF prolactin concentrations higher than their serum levels, which suggested that direct secretion of prolactin from the tumor to the CSF can also occur. Three patients with chromophobe adenomas had normal serum PRL concentrations and elevated CSF prolactin levels which differentiated them from fifteen patients with the primary empty sella syndrome who had normal serum and CSF prolactin levels. The finding of normal CSF prolactin levels in the primary empty sella patients argues against the postulate that the diaphragma sellae significantly influences CSF pituitary peptide concentrations.