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Objective: Cross-sectional studies have reported that the risk of thyroid dysfunction in patients with type 1 diabetes is two- to threefold higher than in the general population. However, longitudinal studies to determine the natural history of thyroid dysfunction in patients with type 1 diabetes are lacking.Research Design and Methods: We analyzed the incidence of thyroid dysfunction over time in a cohort of 58 patients (26 men and 32 women) enrolled in the Diabetes Control and Complications Trial at the University of Tennessee Health Science Center in 1983 and prospectively followed for 18 years. Patients underwent measurement of thyroid function tests (thyroid-stimulating hormone [TSH], thyroxine, and triiodothyronine) every year and thyroid peroxidase (TPO) antibodies at 4-year intervals.Results: A total of 18 patients had hypothyroidism, and 1 patient experienced transient hyperthyroidism. Two subjects developed hypothyroidism 7 and 18 years before the development of diabetes and were excluded from the analysis. The mean age of diagnosis was 19 +/- 2 years for type 1 diabetes and 29 +/- 3 years for hypothyroidism. Hypothyroidism was more common in female (41%) than in male (19%) subjects and in patients with positive TPO antibodies. Patients who were TPO positive were 17.91 times as likely to develop hypothyroidism as patients who were TPO negative (95% CI 3.89-82.54). There were no differences in BMI, lipid profile, and HbA(1c) between patients with and without thyroid dysfunction.Conclusions: This longitudinal study confirms the association between autoimmune thyroid dysfunction and type 1 diabetes. Our results indicate that all subjects with type 1 diabetes should undergo annual screening by serum TSH measurement to detect asymptomatic thyroid dysfunction, particularly those with positive TPO antibodies. [ABSTRACT FROM AUTHOR]

Abstract Background Impaired glucose tolerance (IGT) is a prediabetic state. If IGT can be prevented from progressing to overt diabetes, hyperglycemia-related complications can be avoided. The purpose of the present study was to examine whether pioglitazone (ACTOS®) can prevent progression of IGT to type 2 diabetes mellitus (T2DM) in a prospective randomized, double blind, placebo controlled trial. Methods/Design 602 IGT subjects were identified with OGTT (2-hour plasma glucose = 140–199 mg/dl). In addition, IGT subjects were required to have FPG = 95–125 mg/dl and at least one other high risk characteristic. Prior to randomization all subjects had measurement of ankle-arm blood pressure, systolic/diastolic blood pressure, HbA1C, lipid profile and a subset had frequently sampled intravenous glucose tolerance test (FSIVGTT), DEXA, and ultrasound determination of carotid intima-media thickness (IMT). Following this, subjects were randomized to receive pioglitazone (45 mg/day) or placebo, and returned every 2–3 months for FPG determination and annually for OGTT. Repeat carotid IMT measurement was performed at 18 months and study end. Recruitment took place over 24 months, and subjects were followed for an additional 24 months. At study end (48 months) or at time of diagnosis of diabetes the OGTT, FSIVGTT, DEXA, carotid IMT, and all other measurements were repeated. Primary endpoint is conversion of IGT to T2DM based upon FPG ≥ 126 or 2-hour PG ≥ 200 mg/dl. Secondary endpoints include whether pioglitazone can: (i) improve glycemic control (ii) enhance insulin sensitivity, (iii) augment beta cell function, (iv) improve risk factors for cardiovascular disease, (v) cause regression/slow progression of carotid IMT, (vi) revert newly diagnosed diabetes to normal glucose tolerance. Conclusion ACT NOW is designed to determine if pioglitazone can prevent/delay progression to diabetes in high risk IGT subjects, and to define the mechanisms (improved insulin sensitivity and/or enhanced beta cell function) via which pioglitazone exerts its beneficial effect on glucose metabolism to prevent/delay onset of T2DM. Trial Registration clinical trials.gov identifier: NCT00220961

Context: Sphingolipids are linked to the pathogenesis of type 2 diabetes., Objective: To test the hypothesis that plasma sphingolipid profiles predict incident prediabetes., Design: A case-control study nested in the Pathobiology of Prediabetes in a Biracial Cohort study, a 5-year follow-up study., Setting: Academic health center., Participants: Normoglycemic adults enrolled in the Pathobiology of Prediabetes in a Biracial Cohort study. Assessments included oral glucose tolerance test, insulin sensitivity, and insulin secretion. Participants with incident prediabetes were matched in age, sex, and ethnicity with nonprogressors., Interventions: We assayed 58 sphingolipid species (ceramides, monohexosyl ceramides, sphingomyelins, and sphingosine) using liquid chromatography/tandem mass spectrometry in baseline plasma levels from participants and determined association with prediabetes risk., Main Outcome Measure: The primary outcome was progression from normoglycemia to prediabetes, defined as impaired fasting glucose or impaired glucose tolerance., Results: The mean age of participants (N = 140; 50% Black, 50% female) was 48.1 ± 8.69 years, body mass index 30.1 ± 5.78 kg/m2, fasting plasma glucose 92.7 ± 5.84 mg/dL, and 2-hour plasma glucose 121 ± 23.3 mg/dL. Of the 58 sphingolipid species assayed, higher ratios of sphingomyelin C26:0/C26:1 (OR, 2.73 [95% CI, 1.172-4.408], P = .015) and ceramide C18:0/C18:1 (OR, 1.236 [95% CI, 1.042-1.466], P = .015) in baseline plasma specimens were significantly associated with progression to prediabetes during the 5-year follow-up period, after adjustments for age, race, sex, body mass index, fasting plasma glucose, 2-hour plasma glucose, insulin sensitivity, and insulin secretion., Conclusion: We conclude that the saturated-to-monounsaturated ratios of long-chain ceramide C18:0/C18:1 and very-long-chain sphingomyelin C26:0/C26:1 are potential biomarkers of prediabetes risk among individuals with parental history of type 2 diabetes., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Context: Ceramides and sphingolipids have been linked to type 2 diabetes (T2D). The Ceramides and Sphingolipids as Predictors of Incident Dysglycemia (CASPID) study is designed to determine the association of plasma sphingolipids with the pathophysiology of human T2D., Objective: A comparison of plasma sphingolipids profiles in Black and White adults with (FH+) and without (FH-) family history of T2D., Design: We recruited 100 Black and White FH- (54 Black, 46 White) and 140 FH+ (75 Black, 65 White) adults. Fasting plasma levels of 58 sphingolipid species, including 18 each from 3 major classes (ceramides, monohexosylceramides, and sphingomyelins, all with 18:1 sphingoid base) and 4 long-chain sphingoid base-containing species, were measured by liquid chromatography/mass spectrometry., Results: Sphingomyelin was the most abundant sphingolipid in plasma (89% in FH-), and was significantly elevated in FH+ subjects (93%). Ceramides and monohexosylceramides comprised 5% and 6% of total sphingolipids in the plasma of FH- subjects, and were reduced significantly in FH+ subjects (3% and 4%, respectively). In FH+ subjects, most ceramide and monohexosylceramide species were decreased but sphingomyelin species were increased. The level of C18:1 species of all 3 classes was elevated in FH+ subjects., Conclusion: Elevated levels of sphingomyelin, the major sphingolipids of plasma, and oleic acid-containing sphingolipids in healthy FH+ subjects compared with healthy FH- subjects may reflect heritable elements linking sphingolipids and the development of T2D., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The Ceramides and other Sphingolipids as Predictors of Incident Dysglycemia (CASPID) study tests the overall hypothesis that sphingolipids are pathophysiologic mediators of transition from normal glucose regulation (NGR) to prediabetes, type 2 diabetes (T2DM), and associated complications. The CASPID study utilizes two longitudinal cohorts - the Pathobiology of Prediabetes in a Biracial Cohort (POP-ABC)/Pathobiology and Reversibility of Prediabetes in a Biracial Cohort (PROP-ABC) and the Diabetes Prevention Program (DPP)/DPP Outcomes Study (DPPOS). Normoglycemic POP-ABC/PROP-ABC were followed for 10 years for progression to prediabetes and offered lifestyle intervention to reverse prediabetes. The DPP/DPPOS participants had prediabetes at enrollment, were randomized to placebo, lifestyle intervention, or metformin treatment, and followed for 11 years for progression to T2DM. Using a case-control design, we analyze 76 targeted plasma sphingolipids as predictors of progression from NGR to prediabetes (Aim 1), prediabetes to T2DM (Aim 2), response to interventions (Aim 3), and development of diabetes complications (Aim 4). A sample size of 600 subjects provides >80% power to detect a 20% difference in sphingolipid profiles between comparison groups (alpha = 0.01). At enrollment, POP-ABC participants had a mean age of 47.7 ± 9.00 years, body mass index (BMI) 30.4 ± 6.10 kg/m 2 , fasting glucose 92.9 ± 6.90 mg/dL, and 2-h glucose 130 ± 28.8 mg/dL; DPP participants had a mean age of 51.9 ± 9.44 years, BMI 33.7 ± 6.33 kg/m 2 , fasting glucose 106 ± 7.88 mg/dL, and 2-h glucose 164 ± 16.9 mg/dL. Among normoglycemic participants, those with parental history of T2DM had significantly higher baseline levels of total sphingomyelins, and lower levels of total ceramides and sphingosine, compared with control subjects without familial diabetes history. As the first such study in longitudinal human cohorts, CASPID will elucidate the role of sphingolipids in the pathogenesis of dysglycemia and facilitate the discovery of novel predictive and prognostic biomarkers., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Increased circulating fibroblast growth factor (FGF)-21 and sclerostin levels have been reported in patients with type 2 diabetes (T2D). We assessed the association of FGF-21 and sclerostin with adiposity, glycemia, and glucoregulatory measures in healthy subjects. We studied 20 normoglycemic Black and White offspring of parents with T2D. Assessments included oral glucose tolerance test, insulin sensitivity (Si-clamp), insulin secretion (homeostasis model assessment index of b-cell function [HOMA-B]), and body fat (dual-energy X-ray absorptiometry). Fasting plasma FGF-21 and sclerostin levels were measured with enzyme-linked immunosorbent assays. The participants' mean (+SD) age was 50.4 ± 5.97 years; body mass index (BMI) 32.5 ± 5.86 kg/m 2 ; fasting plasma glucose (FPG) 96.1 ± 5.21 mg/dL, and 2-hour postload glucose 116 ± 5.45 mg/dL. FGF-21 levels were similar in Black people vs White people (0.36 ± 0.15 ng/mL vs 0.39 ± 0.25 ng/mL), men vs women (0.45 ± 0.14 vs 0.44 ± 0.07 ng/mL), correlated positively with BMI (r = 0.23, P = .05) and waist circumference (r = 0.27, P = .04), and inversely with FPG (r = -0.26, P = .05). Sclerostin levels also were similar in Black people (33.5 ± 17.1 pmol/L) vs White people (34.2 ± 6.41 pmol/L), men vs women (35.3 ± 9.01 pmol/L vs 32.3 ± 15.8 pmol/L), and correlated inversely with FPG (r = -0.11 to -0.44) but not adiposity measures. The correlation coefficient between Si-clamp values and FGF-21 levels was -0.31 ( P = .09) compared with 0.04 ( P = .89) for sclerostin levels. FGF-21 and sclerostin levels were not correlated with each other or HOMA-B. Among healthy Black and White subjects, plasma FGF-21 and sclerostin showed differential associations with adiposity but concordant association with FPG levels., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society.)

The ability to predict prediabetes, which affects ∼90 million adults in the US and ∼400 million adults worldwide, would be valuable to public health. Acylcarnitines, fatty acid metabolites, have been associated with type 2 diabetes risk in cross-sectional studies of mostly Caucasian subjects, but prospective studies on their link to prediabetes in diverse populations are lacking. Here, we determined the association of plasma acylcarnitines with incident prediabetes in African Americans and European Americans enrolled in a prospective study. We analyzed 45 acylcarnitines in baseline plasma samples from 70 adults (35 African-American, 35 European-American) with incident prediabetes (progressors) and 70 matched controls (non-progressors) during 5.5-year (mean 2.6 years) follow-up in the Pathobiology of Prediabetes in a Biracial Cohort (POP-ABC) study. Incident prediabetes (impaired fasting glucose/impaired glucose tolerance) was confirmed with OGTT. We measured acylcarnitines using tandem mass spectrometry, insulin sensitivity by hyperinsulinemic euglycemic clamp, and insulin secretion using intravenous glucose tolerance test. The results showed that progressors and non-progressors during POP-ABC study follow-up were concordant for 36 acylcarnitines and discordant for nine others. In logistic regression models, beta-hydroxy butyryl carnitine (C4-OH), 3-hydroxy-isovaleryl carnitine/malonyl carnitine (C5-OH/C3-DC), and octenoyl carnitine (C8:1) were the only significant predictors of incident prediabetes. The combined cut-off plasma levels of <0.03 micromol/L for C4-OH, <0.03 micromol/L for C5-OH/C3-DC, and >0.25 micromol/L for C8:1 acylcarnitines predicted incident prediabetes with 81.9% sensitivity and 65.2% specificity. Thus, circulating levels of one medium-chain and two short-chain acylcarnitines may be sensitive biomarkers for the risk of incident prediabetes among initially normoglycemic individuals with parental history of type 2 diabetes.

Objective: Circulating branched-chain amino acids (BCAAs, isoleucine, leucine, valine) and aromatic amino acids (AAAs, tyrosine and phenylalanine) predicted type 2 diabetes mellitus (T2DM) risk in a Caucasian population. Here, we assessed amino acid levels in relation to incident prediabetes among initially normoglycemic African Americans (AA) and European Americans (EA)., Research Design and Methods: Using a nested case-control design, we studied 70 adults (35 AA, 35 EA) who developed prediabetes (progressors) and 70 matched participants who maintained normoglycemia (nonprogressors) during 5.5 years of follow-up in the Pathobiology of Prediabetes in a Biracial Cohort study. Assessments included plasma amino acid levels, insulin sensitivity, and beta-cell function., Results: The total level of all 18 amino acid assayed was significantly associated with lean mass (r = 0.36, P < 0.0001), waist circumference (r = 0.27, P = 0.001), fasting plasma glucose (r = 0.24, P = 0.005), HOMA-IR (r = 0.22, P = 0.01) and HDL cholesterol (r = -0.18, P = 0.03). Individual amino acid levels were significantly associated with insulin sensitivity and insulin secretion. Compared with nonprogressors, progressors had higher baseline levels of asparagine and aspartic acid (P <0.0001), glutamine/glutamic acid (P = 0.005) and phenylalanine (P = 0.02), and lower histidine (P = 0.02) levels. In fully-adjusted logistic regression models, aspartic acid/asparagine (OR 2.72 [95% CI 1.91-3.87]) and histidine (OR 0.90 [95% CI 0.85-0.96]) were the only amino acids that significantly predicted incident prediabetes., Conclusions: Baseline plasma aspartic acid and asparagine levels predicted progression to prediabetes, whereas histidine levels were protective of prediabetes risk. Thus, the amino acid signature associated with prediabetes in a diverse population may be distinct from that previously linked to T2DM in Caucasians., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Purpose: To compare the safety and efficacy of continuous insulin infusion (CII) via a computer-guided and a standard paper form protocol in a medical intensive care unit (ICU)., Methods: Multicenter randomized trial of 153 ICU patients randomized to CII using the Glucommander (n = 77) or a standard paper protocol (n = 76). Both protocols used glulisine insulin and targeted blood glucose (BG) between 80 mg/dL and 120 mg/dL., Results: The Glucommander resulted in a lower mean BG value (103 ± 8.8 mg/dL vs. 117 ± 16.5 mg/dL, P < 0.001) and in a shorter time to reach BG target (4.8 ± 2.8 vs.7.8 hours ± 9.1 hours, P < 0.01), and once at target resulted in a higher percentage of BG readings within target (71.0 ± 17.0% vs. 51.3 ± 19.7%, P < 0.001) than the standard protocol. Mean insulin infusion rate in the Glucommander was similar to the standard protocol (P = 0.12). The percentages of patients with ≥1 episode of BG <40 mg/dL and <60 mg/dL were 3.9% and 42.9% in the Glucommander and 5.6% and 31.9% in the standard, respectively [P = not significant (NS)]. Repeated measures analyses show that the probabilities of BG reading <40 mg/dL or <60 mg/dL were not significantly different between groups (P = 0.969, P = 0.084) after accounting for within-patient correlations with or without adjusting for time effect. There were no differences between groups in the length of hospital stay (P = 0.704), ICU stay (P = 0.145), or inhospital mortality (P = 0.561)., Conclusion: Both treatment algorithms resulted in significant improvement in glycemic control in critically ill patients in the medical ICU. The computer-based algorithm resulted in tighter glycemic control without an increased risk of hypoglycemic events compared to the standard paper protocol.

Current pharmacological regimens for hypertriglyceridemia and low high-density lipoprotein (HDL) are limited to the peroxisome proliferator-activated receptor (PPAR) alpha activating fibrates, niacin, and statins. This pilot study examined the impact of simultaneous stimulation of cyclic adenosine monophosphate with a beta-adrenergic agonist and PPARgamma with pioglitazone (PIO) on lipoprotein composition in moderately obese, healthy subjects. Subjects were treated with PIO (45 mg) to stimulate PPARgamma or a combination of ephedrine (25 mg TID), a beta-agonist, with caffeine (200 mg TID), a phosphodiesterase inhibitor (ephedrine plus caffeine), or both for 16 weeks. Lipoproteins were separated by gradient ultracentrifugation into very low-density lipoprotein (VLDL), intermediate-density lipoprotein, low-density lipoprotein (LDL), and 3 HDL (L, M, and D) subfractions. Apolipoproteins were measured by high-performance liquid chromatography. PIO alone reduced the core triglyceride (TG) content relative to cholesterol ester (CE) in VLDL (-40%), IDL (-25%), and HDL-M (-38%). Ephedrine plus caffeine alone reduced LDL CE (-13%), phospholipids (-9%), and apolipoprotein (apo) B (-13%); increased HDL-M LpA-I (HDL containing apoA-I without apoA-II, 28%), CE/TG (23%), and CE/apoA-I (8%) while reducing apoA-II (-10%); and increased HDL-L LpA-I (29%). Combination therapy reduced total plasma TG (-28%), LDL cholesterol (LDL-C, -10%), apoB (-16%), apoB/apoA-I ratio (-21%) while increasing HDL cholesterol (HDL-C, 21%), total plasma apoA-I (12%), LpA-I (43%), and apoC-I (26%). It also reduced VLDL total mass (-34%) and apoC-III (-39%), LDL CE (-13%), apoB (-13%), and total mass (-11%). Combination therapy increased HDL-L CE/TG (32%), apoC-I (30%), apoA-I (56%), and LpA-I (70%), as well as HDL-M CE (35%), phospholipids (24%), total mass (19%), apoC-I (25%), apoA-I (18%), and LpA-I (56%). In conclusion, simultaneous beta-adrenergic and PPARgamma activation produced beneficial effects on VLDL, LDL, HDL-L, and HDL-M. Perhaps the most important impact of combination therapy was dramatic increases in LpA-I and apoC-I in HDL-L and HDL-M, which were much greater than the sum of the monotherapies. Because LpA-I appears to be the most efficient mediator of reverse-cholesterol transport and a major negative risk factor for cardiovascular disease, this combination therapy may provide very effective treatment of atherosclerosis.

Objective: To determine whether combination hormone therapy (HT) significantly alters lipoprotein composition in healthy African American women., Methods: Postmenopausal African American women, 45 to 65 years old, were randomly assigned to receive daily HT (conjugated equine estrogen, 0.625 mg, and medroxyprogesterone, 2.5 mg) or placebo (treated, 44; placebo, 16) for 12 weeks. Lipoproteins were separated by gradient ultracentrifugation into very-low-density, intermediate-density, and low-density lipoproteins (VLDL, IDL, and LDL) and 3 high-density lipoprotein (HDL) subfractions (light, medium, and dense--L, M, and D). Apolipoprotein (apo) A-I, A-II, C-III, C-II, and C-I were measured by high-performance liquid chromatography. Apo B, phospholipids, triglycerides, cholesterol, and free cholesterol were measured by standard assays., Results: Total plasma cholesterol, triglycerides, LDL apo B, and total apo B did not change during HT. A small, transient reduction occurred in LDL cholesterol, and a persistent reduction was noted in VLDL apo B, apo C-II, and apo C-III. Total HDL phospholipids, cholesterol, apo A-I, and apo A-II increased, whereas the LDL/HDL ratio and the apo B/apo A-I ratio decreased. Cholesterol ester increased in both HDL-L and HDL-M, but only a transient increase occurred in HDL-L phospholipids. Apo A-I increased in HDL-L, HDL-M, and HDL-D; however, a similar increase occurred in HDL-D apo A-I in the control subjects. Moreover, an increase occurred in apo A-II in HDL-M. A reduction in the apo A-II:A-I ratio in HDL-L but not in HDL-M indicated an increase in HDL-L LpA-I particles. The increase in HDL particles in HDL-M was entirely due to an increase in LpA-I:A-II particles. Apo C-III increased in both HDL-L and HDL-M. The absence of changes in the HDL lipid ratios indicated an unaltered lipid composition of these particles. No changes were found in IDL compositional measurements. In 12 treated patients and 4 control subjects, Lp(a) was detected by ultracentrifugation; no changes were noted in Lp(a) composition or quantity with HT. Total Lp(a) measured by enzyme immunosorbent assay showed a trend toward an increase in treated patients after 12 weeks of HT., Conclusion: African American women had a beneficial response to HT by increasing the number of LpA-I particles in HDL-L and LpA-I:A-II particles in HDL-M as well as cholesterol esters in both. There was a small reduction in VLDL apo B (and thus particle number) but only a transient reduction in LDL cholesterol. A shift of apo C-III from VLDL to HDL was noted. No detrimental changes occurred in any lipoprotein subfraction (specifically, no increase in triglycerides).

Nuclear factor-kappaB (NF-kappaB) and glucocorticoid receptor-alpha (GR-alpha) have diametrically opposed functions in regulating inflammation. We investigated whether unresolving acute respiratory distress syndrome (ARDS) is associated with systemic inflammation- induced glucocorticoid resistance and whether prolonged methylprednisolone administration accelerates the suppression of systemic inflammatory indices and normalizes the sensitivity of the immune system to glucocorticoids. Patients enrolled into a randomized trial evaluating prolonged methylprednisolone administration in unresolving ARDS had serial plasma samples collected before and after randomization. In the plasma, we measured the concentrations of tumor necrosis factor-alpha (TNF-alpha), interleukins (IL) IL-1beta and IL-6, adrenocorticotropic hormone (ACTH), and cortisol. The ability of patient plasma to influence the NF-kappaB and GR-signal transduction systems of normal peripheral blood leukocytes (PBL) was examined. Patients treated with methylprednisolone had progressive and sustained reductions of TNF-alpha, IL-1beta, IL-6, ACTH, and cortisol concentrations over time. Normal PBL exposed to plasma samples collected during methylprednisolone exhibited significant progressive increases in all aspects of GR-mediated activity and significant reductions in NF-kappaB DNA-binding and transcription of TNF-alpha and IL-1beta. These findings provide support for the presence of endogenous glucocorticoid inadequacy in the control of inflammation and systemic inflammation-induced peripheral glucocorticoid resistance in ARDS. Prolonged methylprednisolone administration accelerated the resolution of both systemic inflammation and peripheral acquired glucocorticoid resistance in ARDS.

Replication of Staphylococcus aureus is significantly enhanced in the presence of recombinant interleukin (IL)-1beta. In this study, specific binding of IL-1beta to the surface of S. aureus significantly increased growth of S. aureus in the presence of IL-1beta and IL-1ra in a concentration-dependent manner. Although IL-1ra enhanced the growth of S. aureus, there was a significant reduction in IL-1beta-mediated growth enhancement of S. aureus when 25-fold excess amounts of IL-1ra (in comparison with the IL-1beta concentration) were present in the culture medium. Thus, IL-1beta may influence the growth of S. aureus through a receptor-mediated event. By using 5 linear peptides spanning limited regions of IL-1beta, the growth-promoting regions were localized to amino acid residues 118-147 and 208-240. These results build on the newly evolved concept of direct interactions between the soluble mediators of inflammation and infectious agents.

Ineffective lung repair in patients with unresolving acute respiratory distress syndrome (ARDS) is accompanied by progressive fibroproliferation, inability to improve lung injury score (LIS), progressive multiple organ dysfunction syndrome (MODS), and an unfavorable outcome. Our aim was to investigate the relationship between fibrogenesis, pulmonary and extrapulmonary organ dysfunction, and outcome during the natural course of ARDS and in response to prolonged methylprednisolone treatment. We investigated 29 patients with ARDS. We obtained serial measurements of plasma and BAL procollagen aminoterminal propeptide type I (PINP) and type III (PIIINP) levels and components of the lung injury score (LIS) and MODS score. A reduction in LIS greater than one point from day 1 to day 7 of ARDS divided patients in improvers (group 1, n = 7) and nonimprovers (n = 22). Nonimprovers included those who were recruited (day 9 +/- 3 of ARDS) into a prospective, randomized, double-blind, placebo-controlled trial investigating prolonged methylprednisolone therapy in unresolving ARDS (group 2, n = 17), and those who died (all by day 10 of ARDS) prior to meeting eligibility criteria for the randomized trial (group 3, n = 5). On day 1 of ARDS, plasma PINP or PIIINP levels were elevated in all patients. By day 7 of ARDS, mean plasma PINP or PIIINP levels were unchanged in group 1 but increased significantly in group 2 (p = 0. 0002) and group 3 (p = 0.03). On day 7, patients with plasma PINP levels less than 100 ng/ml were 2.5 times more likely to survive (95% CI: 0.855-7.314), and patients with plasma PIIINP levels greater than 25 ng/ml were nine times more likely to die (95% CI: 1. 418-55.556). In group 2, patients taking placebo (n = 6) had no change in plasma PINP or PIIINP levels over time, while patients treated with methylprednisolone (n = 11) had a rapid and sustained reduction in mean plasma and bronchoalveolar lavage (BAL) PINP and PIIINP levels. By day 3 of treatment, mean plasma PINP and PIIINP levels (ng/ml) decreased from 100 +/- 9 to 45 +/- 8 (p = 0.0001) and 31 +/- 3 to 12 +/- 3 (p = 0.0008), respectively. After 8 to 15 d of methylprednisolone, mean BAL PINP and PIIINP levels (ng/ml) decreased from 63 +/- 25 to 6 +/- 23 (p = 0.002) and 42 +/- 5 to 10 +/- 3 (p = 0.003), respectively. Estimated partial correlation coefficients indicated that as plasma PINP and PIIINP levels decreased over the first 7 d of methylprednisolone treatment, positive end-expiratory pressure, creatinine, bilirubin, and temperature also decreased, while PaO2:FIO2 increased. In early ARDS, plasma PINP and PIIINP levels are elevated and continue to increase over time in those not improving. Among nonimprovers, those randomized to prolonged methylprednisolone treatment had a rapid and significant reduction in plasma and BAL aminoterminal propeptide levels and similar changes in lung injury and MODS scores. These findings provide additional evidence of an association between biological efficacy and physiologic response during prolonged methylprednisolone treatment of unresolving ARDS.

Background: Inflammatory cytokines (ICs) are important modulators of injury and repair. ICs have been found to be elevated in the BAL of patients with both early and late ARDS. We tested the hypothesis that recurrent injury to the alveolocapillary barrier and amplification of intra-alveolar fibroproliferation observed in nonresolving ARDS is related to a persistent inflammatory response. For this purpose, we obtained serial measurements of BAL IC and correlated these levels with lung injury score (LIS), BAL indexes of endothelial permeability (albumin, total protein [TP]), and outcome., Methods: We prospectively studied 27 consecutive patients with severe medical ARDS. Using enzyme-linked immunosorbent assay methods, levels of tumor necrosis factor-alpha (TNF-alpha) and interleukins (IL) 1 beta, 2, 4, 6, and 8 were measured at frequent intervals in both plasma and BAL. In 22 patients, bilateral BAL was obtained on day 1 of ARDS and at weekly intervals when possible. Right and left BALs were analyzed separately for IC levels, total cell count and differential, albumin, TP, and quantitative bacterial cultures., Results: On day 1 of ARDS, the 10 nonsurvivors had significantly higher (p = 0.0002) BAL TNF-alpha, IL-1 beta, IL-6, and IL-8 levels, which remained persistently elevated over time, indicating a continuous injury process. In contrast, the 12 survivors had a lesser elevation and a rapid reduction over time. Initial BAL IL-2 and IL-4 levels were significantly higher in patients with sepsis (p = 0.006); both increased over time in survivors and nonsurvivors. BAL levels of TNF-alpha, IL-1 beta, IL-6, and IL-8 correlated with BAL albumin and TP concentrations but not with LIS or ratio of arterial oxygen tension to inspired oxygen concentration. BAL: plasma ratios were elevated for all measured cytokines, suggesting a pulmonary origin. On day 1 of ARDS, nonsurvivors had significantly higher (p = 0.04) BAL: plasma ratios for TNF-alpha, IL-1 beta, IL-6, and IL-8. Over time, BAL:plasma ratios for TNF-alpha, IL-1 beta and IL-6 remained elevated in nonsurvivors and decreased in survivors., Conclusions: Our findings indicate that an unfavorable outcome in ARDS is associated with an initial, exaggerated, pulmonary inflammatory response that persists unabated over time. Plasma IC levels parallel changes in BAL IC levels. The BAL:plasma ratio results suggest, but do not prove, a pulmonary origin for IC production. BAL TNF-alpha, IL-1 beta, and IL-8 levels correlated with BAL indices of endothelial permeability. In survivors, reduction in BAL IC levels over time was associated with a decline in BAL albumin and TP levels, suggesting effective repair of the endothelial surface. These findings support a causal relationship between degree and duration of lung inflammation and progression of fibroproliferation in ARDS.

Background: In late ARDS, a persistent and exaggerated inflammatory response causes recurrent injury to the alveolocapillary barrier and amplification of intra-alveolar fibroproliferation. When ARDS patients fail to improve, corticosteroid (CS) rescue treatment frequently leads to rapid improvements in lung function. We tested the hypothesis that response to CS treatment is related to suppressing the inflammatory response by comparing changes in lung function to inflammatory cytokine (IC) levels in the plasma and BAL., Methods: Blood samples were obtained on days 1, 3, 5, and 7 of ARDS, and on days -5, -3, 0 (initiation of treatment), +3, +5, +7, +10, and +14 of CS treatment. Bilateral BAL was obtained on day 1 of ARDS, before administration of CS treatment, and at weekly intervals. We analyzed changes in IC levels during CS treatment in relation to improvements in lung injury score (LIS), indices of endothelial permeability, and final outcome. We also analyzed data to identify timing to a significant reduction in plasma IC levels and predictors of response., Results: Nine patients entered the study. CS treatment was initiated 15 +/- 9 days into ARDS. Improvement in LIS (> 1-point reduction) was rapid (< 7 days) in five, delayed (< 14 days) in two, and absent in two. Baseline plasma and BAL IC levels in study patients were similar to a previously reported comparison group of 12 ARDS nonsurvivors. No significant changes in plasma and BAL IC levels were observed before CS administration. Following initiation of CS treatment, significant reductions in plasma tumor necrosis factor-alpha and interleukin 6 (IL-6) levels were seen by day 7 in both rapid and delayed responders (p = 0.03). IL-1 beta was significantly reduced by day 5 (p = 0.04) in rapid responders and by day 10 (p = 0.03) in delayed responders. In responders, improvement in LIS and BAL albumin paralleled reduction in plasma and BAL IC levels. At initiation of treatment, rapid responders had significantly lower tumor necrosis factor-alpha and IL-6 levels. Nonresponders had a significantly higher plasma IL-6 level on days 1 to 3 of ARDS (p = 0.004) and lower ratio of arteriolar oxygen tension to inspired oxygen concentration at initiation of treatment (p < 0.01)., Conclusions: In patients with late ARDS and a low likelihood of survival, prolonged corticosteroid rescue treatment was associated with a reduction in plasma and BAL IC levels and parallel improvements in indices of endothelial permeability and LIS.

Three groups of age- and weight-matched men (aged 40 to 70 years) without diabetes were studied: controls (n = 10), plasma triglycerides (TG) less than 180 mg/dL and no cardiovascular disease (CVD); HTG-CVD (n = 11), hypertriglyceridemic (HTG) (TG > 240 mg/dL) without CVD; and HTG+CVD (n = 10), HTG (TG > 240 mg/dL) with documented CVD. HTG+CVD subjects had higher fasting and post-oral glucose tolerance test insulin levels than the other two groups, respectively. Very-low-density lipoprotein (VLDL)+chylomicrons (CMs), intermediate-density lipoprotein (IDL), low-density lipoprotein (LDL), and three high-density lipoprotein (HDL) subfractions (HDL-L, HDL-M, and HDL-D, from least to most dense) were isolated by gradient ultracentrifugation. Fasting lipoproteins were similar in HTG groups, except for higher VLDL lipid to apolipoprotein (apo) B ratios (P < .04) in the HTG+CVD group. Subjects were fed a high-fat mixed meal, and lipoprotein composition was determined at 3, 6, 9, and 12 hours postprandially. Postprandial responses of the core lipids (TG and cholesterol esters [CE]) in all of the lipoprotein subfractions were similar in the two HTG groups at each time point. However, both controls and HTG-CVD subjects had increases in HDL-M phospholipid (PL) at 9 and 12 hours with no change in HDL-D PL. The HTG+CVD group, on the other hand, had no increase in HDL-M PL and had a substantial reduction in HDL-D PL. These changes resulted in significant increases in HDL-M and HDL-D PL to apo A-I ratios in both controls and HTG-CVD subjects between 6 and 12 hours, whereas there was no increase seen in the HTG+CVD group. The HTG-CVD group also had a significantly greater increase in the VLDL+CM PL to apo B ratio (P = .038) at 3 hours than the HTG+CVD group. This diminished amount of surface lipid per VLDL particle may account for the late decrease in the HDL-D PL to apo A-I ratio seen in HTG+CVD patients. There were no other postprandial lipid or apolipoprotein differences between the two HTG groups. We conclude therefore that the major postprandial lipoprotein abnormality in these HTG+CVD patients was a failure to increase the PL content per particle in VLDL+CM, HDL-M, and HDL-D. This abnormality could prevent the usual increase in reverse cholesterol transport seen in postprandial plasma and therefore contribute to their increased incidence of CVD. The greater insulin resistance seen in these patients also appears to contribute significantly to their CVD.

Objective: To demonstrate bioavailability of 3 weeks of oral micronized DHEA and to delineate changes induced on insulin sensitivity, morphometric indexes, and lipoprotein profiles., Design: Oral micronized DHEa (50 mg/d) was administered in 3-week treatments to 11 postmenopausal women in a prospective, placebo-controlled, randomized, blinded, crossover trial with an interarm washout. After dose (23 hour) serum DHEA, DHEAS, T, and cortisol levels were measured, as were fasting lipoproteins, oral glucose tolerance tests (OGTT), T-lymphocyte insulin binding and degradation, and urine collagen cross-links. Morphometric changes were determined by hydrostatic weighing., Results: Dehydroepiandrosterone sulfate, DHEA, T, and free T increased up to two times premenopausal levels with treatment. Fasting triglycerides declined; no change in collagen cross-links or morphometric indexes was noted. Oral glucose tolerance test parameters did not change, but both T-lymphocyte insulin binding and degradation increased with DHEA., Conclusion: Fifty milligrams per day of oral DHEA gives suprahysiologic androgen levels; 25 mg/d may be more appropriate. Dehydroepiandrosterone enhanced tissue insulin sensitivity and lowered serum triglycerides. Rationale is provided for postmenopausal replacement therapy with this androgen.

Background: Inflammatory cytokines have been related to the development of adult respiratory distress syndrome (ARDS), shock, and multiple organ dysfunction syndrome (MODS). We tested the hypothesis that unfavorable outcome in patients with ARDS is related to the presence of a persistent inflammatory response. For this purpose, we evaluated the behavior of inflammatory cytokines during progression of ARDS and the relationship of plasma inflammatory cytokines with clinical variables and outcome., Methods: We prospectively studied 27 consecutive patients with severe medical ARDS. Plasma levels of tumor necrosis factor alpha (TNF-alpha) and interleukins (ILs) 1 beta, 2, 4, 6, and 8 were measured (enzyme-linked immunosorbent assay [ELISA] method) on days 1, 2, 3, 5, 7, 10, and 12 of ARDS and every third day thereafter while patients were receiving mechanical ventilation. Subgroups of patients were identified based on outcome, cause of ARDS, presence or absence of sepsis, shock, and MODS at the time ARDS developed. Subgroups were compared for levels of plasma inflammatory cytokines on day 1 of ARDS and over time., Results: Of the 27 patients, 13 survived ICU admission and 14 died (a mortality rate of 52%). Overall mortality was higher in patients with sepsis (86 vs 38%, p < 0.02). The mean initial plasma levels of TNF-alpha, IL-1 beta, IL-6, and IL-8 were significantly higher in nonsurvivors (p < 0.0001) and in those patients with sepsis (p < 0.0001). Plasma levels of IL-1 beta (p < 0.01) and IL-6 (p = 0.03) were more strongly associated with patient outcome than cause of ARDS (p = 0.8), lung injury score (LIS), APACHE II score, sepsis (p = 0.16), shock, or MODS score. Plasma levels of TNF-alpha, IL-1 beta, IL-6, and IL-8 remained significantly elevated over time (p < 0.0001) in those who died. Although it was the best early predictor of death (p < 0.001), plasma IL-2 > 200 pg/mL lost its usefulness after the first 48 h. A plasma IL-1 beta or IL-6 level > 400 pg/mL on any day in the first week of ARDS was associated with a low likelihood of survival., Conclusions: Our findings indicate that unfavorable outcome in acute lung injury is related to the degree of inflammatory response at the onset and during the course of ARDS. Patients with higher plasma levels of TNF-alpha, IL-1 beta, IL-6, and IL-8 on day 1 of ARDS had persistent elevation of these inflammatory cytokines over time and died. Survivors had lesser elevations of plasma inflammatory cytokines on day 1 of ARDS and a rapid reduction over time. Plasma IL-1 beta and IL-6 levels were consistent and efficient predictors of outcome.

Objective: This study tests the hypothesis that dehydroepiandrosterone or its metabolic products are immunomodulatory in postmenopausal women with relative adrenal androgen deficiency., Study Design: A prospective, randomized, double-blind, crossover study of 11 subjects with 3-week treatment arms separated by a 2-week washout period was performed. Immunologic evaluation at the beginning and end of the treatment arms consisted of flow cytometry to delineate T-cell populations, in vitro T-cell mitogenic response and cytokine production, and natural killer cell cytotoxicity. Statistical analysis was based on a split-plot design with analysis of variance with repeated measures., Results: Dehydroepiandrosterone supplementation decreased CD4+ (helper) T cells and increased CD8+/CD56+ (natural killer) cells. Although T-cell mitogenic and interleukin-6 responses were inhibited, natural killer cell cytotoxicity increased dramatically., Conclusions: These data provide the first in vivo evidence in human for an immunomodulatory effect of dehydroepiandrosterone. The salutary immune changes could account for clinical and experimental evidence of antioncogenic effects of this steroid. This study provides a strong rationale for further clinical studies on dehydroepiandrosterone supplementation in adrenal androgen-deficient states.

The dansyl chloride technique in conjunction with thin layer chromatography and autoradiography has shown that dipivalyl epinephrine is a pro-drug in the human eye. Dipivalyl epinephrine appears to be a more effective epinephrine compound, in that it penetrates the cornea approximately 17 times greater than epinephrine.

We have studied the time sequence degradation of native insulin by insulin protease from human fibroblast using multiple steps involving purification of the products by high performance liquid chromatography, determination of peak composition by amino acid sequence analysis, and confirmation of structure by mass spectrometry and thus elucidated the sites of cleavage of insulin by human insulin protease. We observed that as early as 0.5 min of incubation, three major new peptide peaks, intact insulin, and four smaller peptide peaks can be detected. The major peptides are portions of the insulin molecule, with the amino ends of the A and B chains or the carboxyl ends of the A and B chains still connected by disulfide bonds. Peptide peak I is A1-13-B1-9. Peptide peak II is A1-14-B1-9. Peptide peak III is A14-21-B14-30. The smaller peptide peaks are A14-21-B17-30, A15-21-B14-30, A15-21-B10-30, and A14-21-B10-30. The major peptide bond cleavage sites therefore consist of A13-14, A14-15, B9-10, B13-14, and B10-17. With longer incubation times, peptide peak II appears to lose the A14 tyrosine to form peptide peak I. This peptide I, which is the amino end of the A and B chains, is not further degraded even after 1.5 h of incubation. With longer incubation times, the peptides containing the carboxyl ends of the A and B chains are further degraded to form products from cleavage at the A18-19, B14-15, B25-26, and a small amount of A19-20, B10-11, and B24-25 cleavage and the emergence of 2-5-amino acid peptide chains, tyrosine, alanine, histidine, and leucine-tyrosine. We conclude, based on the three-dimensional structure of insulin, that human insulin protease recognizes the alpha-helical regions around leucine-tyrosine bonds and that final degradation steps to small peptides do not require lysosomal involvement.

Radioimmunoassay (RIA) and high performance liquid chromatography (HPLC) with ultraviolet absorbance detection have been compared as potential tools for cyclosporine pharmacokinetic studies in dogs. RIA clearly affords greater assay sensitivity, although crossreactivity with cyclosporine metabolites causes an over-estimation of parent drug concentrations with a subsequent reduction in the apparent values of clearance and volume of distribution. HPLC appears to be specific for parent cyclosporine. Thus, with the sacrifice of some sensitivity, HPLC-measured time-course data afford more reliable estimates of cyclosporine pharmacokinetic parameters. After the selection of a dosage regimen from preliminary studies, the pharmacokinetics of i.v.-administered cyclosporine were studied in six adult male mongrel dogs. Following administration of 20 mg/kg by constant-rate 30-min i.v. infusion the time courses of cyclosporine were studied in plasma and urine. Concentrations were measured by reversed-phase HPLC with ultraviolet absorbance detection. Data were fitted to triexponential equations using a digital computer with the CSTRIP and NONLIN programs, and pharmacokinetic parameters were calculated. Present findings suggest that cyclosporine is slowly yet extensively distributed into peripheral body regions that might serve as slowly releasing storage areas. Large volumes of distribution along with moderately slow clearances resulted in long half-lives for the disposition of cyclosporine. Less than 1% of the administered dose was recovered as parent cyclosporine in the urine, suggesting that renal clearance of cyclosporine was negligible. The potential relevance of present findings to cyclosporine therapy of transplant patients is discussed.