Safety, tolerability and pharmacokinetics of liposomal curcumin in healthy humans.

INTRODUCTION: Experimental studies have shown that liposomal curcumin can exert a reduction in tumor growth in pancreatic and colorectal cancer. In this phase I clinical trial we investigated the pharmacokinetics, safety, and tolerability of intravenously administered liposomal curcumin in healthy subjects. MATERIAL AND METHODS: 50 male and female participants were included in this randomized, placebo-controlled double-blind phase I dose escalation study. Subjects received a single dose of liposomal curcumin (10 - 400 mg/m2; n = 2 - 6 per group) or placebo over 2 hours intravenously. RESULTS: Dose-dependent increases in the plasma concentrations of curcumin and its metabolite tetrahydrocurcumin (THC) were detected. After the end of drug infusion, curcumin and THC plasma concentrations decreased within 6 - 60 minutes below the limit of quantification. Mean urinary excretion was ~ 0.1% of total systemic clearance. Liposomal curcumin was tolerated well, but a transient red blood cell echinocyte formation with concomitant increase in mean cellular volume was observed at dosages ≥ 120 mg/m2. CONCLUSION: Short-term intravenous dosing of liposomal curcumin appears to be safe up to a dose of 120 mg/m2. Changes in red blood cell morphology may represent a dose limiting sign of toxicity.

Association of endostatin with mortality in patients with chronic heart failure.

BACKGROUND: Experimental data imply that in decompensated heart failure (HF), the anti-angiogenic factor endostatin is increased. This study aimed to investigate whether the angiogenesis inhibitor endostatin is related to the risk of all-cause mortality in a prospective cohort study of chronic HF patients. METHODS: In this prospective observational cohort study, endostatin serum concentrations were determined in patients with chronic HF. Mortality data were recorded during a median follow-up of 31 months. RESULTS: One fifty one patients were included. The overall mortality rate was 20%. Baseline endostatin concentrations > 245 ng/mL were associated with higher risk of all-cause mortality [HR 8·7 (95% CI 2·5-30·0); P = 0·001] in the multivariate analysis as compared to endostatin concentrations ≤ 245 ng/mL. When both endostatin and NT-proBNP were above the calculated cut-off of 245 ng/mL and 2386 pg/mL, respectively, the prognostic utility of both biomarkers increased [HR 40·8 (95% CI 4·7-354·6); P = 0·001] compared with values lower than the cut-offs. CONCLUSIONS: Serum endostatin concentrations are independently associated with all-cause mortality. Furthermore, combination of endostatin and NT-proBNP discriminates patients at high risk.

VPAC1 receptor expression in peripheral blood mononuclear cells in a human endotoxemia model.

BACKGROUND: Vasoactive intestinal peptide (VIP) exerts immune-modulatory actions mainly via VPAC1 receptor stimulation. VPAC1 may be a treatment target of inflammatory diseases, but little is known about the receptor expression profile in immune-competent cells in vivo. MATERIAL AND METHODS: 20 male healthy subjects received a single intravenous bolus of 2 ng/kg body weight Escherichia coli endotoxin (LPS). Receptor status was evaluated in peripherial blood cells before and 3, 6 and 24 h after LPS by FACS analysis and q-PCR. VIP plasma concentrations were measured by ELISA. RESULTS: Granulocytes accounted for 51% of leukocytes at baseline and 58 ± 37% were positive for VPAC1. The granulocyte population increased 2.6 fold after LPS, and a transient down-regulation of VPAC1 to 28 ± 23% was noted at 3 h (p < 0.001), which returned to baseline at 24 hours. Baseline VPAC1 expression was low in lymphocytes (6.3 ± 3.2%) and monocytes (11 ± 9.6%). In these cells, LPS up-regulated VPAC1 at 6 h (13.2 ± 4.9%, p < 0.001) and 24 h (31.6 ± 20.5%, p = 0.001), respectively. Consistent changes were noted for the VIP-receptors VPAC2 and PAC1. VPAC1, VPAC2 and PAC1 mRNA levels were unchanged in peripheral blood mononuclear cells (PBMC). VIP plasma concentration increased from 0.5 ± 0.3 ng/ml to 0.7 ± 0.4 ng/ml at 6 h after LPS (p < 0.05) and returned to baseline within 24 h. CONCLUSION: The time profile of VPAC receptor expression differs in granulocytes, monocytes and lymphocytes after LPS challenge in humans. Changes in circulating VIP concentrations may reflect innate immune responses.

E. coli endotoxin modulates the expression of Sirtuin proteins in PBMC in humans.

BACKGROUND: Sirtuin (SIRT) proteins are class I histone deacetylases displaying gene regulatory functions in inflammatory, cancer, and metabolic diseases. These SIRT actions involve the nuclear factor κ B and its inhibitor I κ B pathway. However, the regulation of SIRT in vivo is still unclear. MATERIAL AND METHODS: In a human endotoxemia model, 20 healthy male subjects received an intravenous bolus of 2 ng/kg body weight Escherichia coli endotoxin (LPS). SIRT expression was investigated in peripheral blood mononuclear cells (PBMC) with qPCR and Western blot before and 3 hours, 6 hours, and 24 hours after LPS challenge. Additionally, SIRT regulation was studied in vitro in cultivated PBMC after incubation with 20 ng/mL LPS. RESULTS: A downregulation by >40% of SIRT1 mRNA was detectable 3 hours after LPS and of SIRT3 mRNA 6 hours after LPS. SIRT3, IκBα, and IκB-ß protein expressions were decreased 3 and 6 hours after LPS. SIRT2 mRNA or protein expression did not change following LPS. These findings were consistent in vitro and associated with augmented phosphorylation of IκB-ß. DISCUSSION: In this E. coli endotoxemia model, SIRT1 and SIRT3 mRNA expressions in PBMC in humans were reduced after LPS challenge. This suggests that SIRT may represent an inflammatory target protein in vivo.

Adipokines in type 1 diabetes after successful pancreas transplantation: normal visfatin and retinol-binding-protein-4, but increased total adiponectin fasting concentrations.

OBJECTIVE: In type 1 diabetes mellitus (T1DM), the release of many hormones, not only from beta-cells, but also from adipocytes (adipokines) may be altered. After successful pancreas-kidney-transplantation (PKTx), T1DM patients can revert to a nondiabetic metabolism, but it is unclear whether alterations of adipokines are still present after PKTx. DESIGN, PATIENTS AND MEASUREMENTS: Concentrations of adipokines [visfatin, retinol-binding protein-4 (RBP-4), adiponectin, high molecular weight (HMW) adiponectin] were measured at fasting in 10 PKTx and in 19 T1DM. Nondiabetic healthy controls (CON, n = 9) and six nondiabetic patients after kidney transplantation (KTx) were examined as control groups. In PKTx, KTx and CON, indices of insulin sensitivity (OGIS) and beta cell function (adaptation index, AI) were calculated from 75 g oral glucose tolerance test (OGTT) data. RESULTS: Fasting serum visfatin (T1DM: 56 +/- 4 microg/l, PKTx: 42 +/- 6 microg/l, KTx: 39 +/- 3 microg/l, CON: 40 +/- 3 microg/l) and RBP-4 (T1DM: 490 +/- 26 microg/l, PKTx: 346 +/- 39 microg/l, KTx: 401 +/- 13 microg/l, CON: 359 +/- 36 microg/l) was increased by 40% and 36%, respectively (each P < 0.03) in T1DM only. Levels were positively correlated with HbA1c in all subjects (visfatin: r = 0.43, P < 0.004; RBP-4: r = 0.46, P < 0.03). Fasting plasma adiponectin was 80% higher in T1DM and in PKTx (T1DM: 18 +/- 2 mg/l, PKTx: 18 +/- 3 mg/l, KTx: 12 +/- 3 mg/l, CON: 10 +/- 1 mg/l; P < 0.04) and was positively correlated with diabetes duration (r = 0.37, P < 0.02). HMW/total adiponectin ratio was increased in T1DM (P < 0.02). PKTx displayed a normoglycaemic metabolism as insulin sensitive as CON, but AI was lower than in CON and KT (P < 0.01). CONCLUSIONS: T1DM after successful PKTx show normal fasting visfatin and RBP-4 levels and HMW-adiponectin/adiponectin-ratio, which are elevated in T1DM, whereas total adiponectin levels are similarly increased in T1DM and PKTx patients.

[Drug interactions in geriatric medicine]. / Medikamenteninteraktionen in der Geriatrie.

Drug interactions are often seen in elder patients due to polymedication. They can lead to unwanted side effects attended with unspecific symptoms such as vertigo, lateropulsion, fatigue or confusion. This can result in a prescribing cascade. Interactions can take place on all pharmacodynamic and pharmacokinetic levels, whereas the CYP enzyme-dependent metabolism seems to play a key role. The incidence of drug interactions is quite high and clinical relevant interactions are also not uncommon. Especially drugs with a low therapeutic index are more likely to be the target of clinical relevant interactions. However, most of the drug interactions can be managed by dose-reduction or by replacing one of the possibly interacting drugs. An important point is to remember the possibility of drug interactions.

Safety and tolerability of topically administered autologous, apoptotic PBMC secretome (APOSEC) in dermal wounds: a randomized Phase 1 trial (MARSYAS I).

Developing effective therapies against chronic wound healing deficiencies is a global priority. Thus we evaluated the safety of two different doses of topically administered autologous APOSEC, the secretome of apoptotic peripheral blood mononuclear cells (PBMCs), in healthy male volunteers with artificial dermal wounds. Ten healthy men were enrolled in a single-center, randomized, double-blinded, placebo-controlled phase 1 trial. Two artificial wounds at the upper arm were generated using a 4-mm punch biopsy. Each participant was treated with both topically applied APOSEC and placebo in NuGel for 7 consecutive days. The volunteers were randomized into two groups: a low-dose group (A) receiving the supernatant of 12.5 × 106 PBMCs and a high-dose group (B) receiving an equivalent of 25 × 106 PBMCs resuspended in NuGel Hydrogel. Irradiated medium served as placebo. The primary outcome was the tolerability of the topical application of APOSEC. All adverse events were recorded until 17 days after the biopsy. Local tolerability assessment was measured on a 4-point scale. Secondary outcomes were wound closure and epithelization at day 7. No therapy-related serious adverse events occurred in any of the participants, and both low- and high-dose treatments were well tolerated. Wound closure was not affected by APOSEC therapy.

Human pharmacokinetics of high dose oral curcumin and its effect on heme oxygenase-1 expression in healthy male subjects.

PURPOSE: Heme oxygenase-1 (HO-1) has been proposed to exert pharmacological benefits by its antioxidative and anti-inflammatory effects. HO-1 expression may be affected by the GT length polymorphism in the promoter region of the HO-1 gene. We investigated the inducibility of HO-1 by orally administered curcumin in healthy male subjects and its correlation with the GT length polymorphism. METHODS: In an open label uncontrolled phase-1 pilot study, ten male subjects received 12 g of oral curcumin. To investigate the effects of the GT length polymorphism on the inducibility of HO-1, five subjects with homozygous short and five with homozygous long GT genotypes were studied. Plasma concentrations of curcumin, bilirubin, HO-1 mRNA, and protein expression in peripheral blood mononuclear cells (PBMCs) were analyzed over 48 hours. RESULTS: At a detection limit of 1 µg/mL curcumin could not be detected in plasma of any subject. Compared to baseline, HO-1 mRNA and protein levels were not induced in PBMCs at any time point up to 48 hours. There was no correlation between any of the parameters and GT length polymorphism. CONCLUSIONS: Oral curcumin administration has low bioavailability and does not induce HO-1 on mRNA or protein level in PBMCs.

Effects of smoking cessation on ß-cell function, insulin sensitivity, body weight, and appetite.

OBJECTIVE: To stop smoking is commonly associated with significant weight gain, but the mechanisms for this are poorly understood. We assessed the effects of smoking cessation on body weight, insulin sensitivity, ß-cell function, and appetite. SUBJECTS AND METHODS: Twenty-seven long-term smokers (n=27; nine females/18 males, 28±1 years, 22.9±0.6 kg/m(2)) attending an ambulatory smoking cessation program in a community hospital in Vienna, Austria were examined at baseline (Visit A; still smoking) and after a minimum of 3 months of smoking abstinence (Visit B; n=14); relapsed smokers were not followed up. Participants underwent 3-h oral glucose tolerance tests and body composition measurements at each study visit. Fasting (QUICKI) and dynamic (oral glucose insulin sensitivity (OGIS)) insulin sensitivity and ß-cell secretion (insulinogenic index 140 (IGI40)) were calculated. Food intake was quantified with a free choice buffet. Fasting plasma concentrations of neuropeptide-Y (NPY), peptide-YY (PYY), glucagon-like peptide 1 (GLP1), leptin, ghrelin, and visfatin were measured. RESULTS: AFTER 3 MONTHS' SMOKING ABSTINENCE, BODY WEIGHT, AND FAT MASS WERE INCREASED (+4 AND +22% RESPECTIVELY, P0.05) AND FASTING INSULIN SENSITIVITY DETERIORATED (QUICKI: post, 0.37±0.02 vs baseline, 0.41±0.2; P<0.05), while OGIS remained unchanged throughout. IGI40 increased by 31% after >3 months' smoking abstinence (P<0.01). Carbohydrate ingestion increased after stopping smoking (P<0.05). NPY fasting levels were increased after >3 months (P<0.05), PYY, GLP1, leptin, ghrelin, and visfatin were unchanged. CONCLUSION: Smoking cessation is associated with transient metabolic changes including increased ß-cell secretion in response to glucose and fasting insulin resistance. These alterations may be associated with or contribute to the body weight gain after smoking cessation.

Effect of liposomal curcumin on red blood cells in vitro.

BACKGROUND: The anti-inflammatory and antiproliferative agent curcumin has poor oral bioavailability and solubility in plasma. Liposomal formulations have therefore been developed, but the toxicity of these preparations is not yet established. We investigated the influence of free and liposomally formulated curcumin on human red blood cell (RBC) morphology in vitro. MATERIALS AND METHODS: EDTA-buffered whole blood from two healthy individuals was incubated with different concentrations (1, 10, 100 µg/ml) of free or liposomal curcumin. RBC morphology and mean cellular volume (MCV) were examined at up to 4 hours of incubation. RESULTS: Dose-dependent echinocyte formation was observed after incubation with free, and liposomal curcumin, with a threshold concentration of 10 µg/ml and peak effect after 30 minutes. A concomitant increase in mean cellular volume was detectable. CONCLUSION: Curcumin and liposomal curcumin cause dose-dependent changes in the shape of RBCs. This effect may represent an early sign of dose-limiting toxicity following intravenous administration.

Vasoactive intestinal peptide (VIP) receptor expression in monocyte-derived macrophages from COPD patients.

Vasoactive intestinal peptide (VIP) is one of the most abundant molecules found in the respiratory tract. Due to its anti-inflammatory and bronchodilatatory properties, it has been proposed as a novel treatment for chronic obstructive pulmonary disease (COPD). The actions of VIP are mediated via three different G-protein-coupled receptors (VPAC1, VPAC2 and PAC1) which are expressed in the respiratory tract and on immunocompetent cells including macrophages. Alveolar macrophages (AM) are key players in the pathogenesis of COPD and contribute to the severity and progression of the disease. While VPAC1 has been reported to be elevated in subepithelial cells in smokers with chronic bronchitis, little is known about VPAC expression of AM in COPD patients. AM from COPD patients show a strong VPAC1 expression which exceeds VPAC2. A similar receptor expression pattern was also observed in lipopolysaccharide (LPS)-activated monocyte-derived macrophages (MDM) from healthy volunteers and COPD patients. VIP has been shown to down-regulate interleukin 8 (IL-8) secretion significantly in MDM after LPS stimulation. The response to VIP was similar in MDM from COPD patients and healthy volunteers. Our results indicate that VPAC1 up-regulation in macrophages is a common mechanism in response to acute and chronic pro-inflammatory stimuli. Although VPAC1 up-regulation is dominant, both receptor subtypes are necessary for optimal anti-inflammatory signaling. The high VPAC1 expression in AM may reflect the chronic pro-inflammatory environment found in the lung of COPD patients. Treatment with VIP may help to decrease the chronic inflammation in the lung of COPD patients.

Primary sources and immunological prerequisites for sST2 secretion in humans.

AIMS: Serum levels of the soluble growth stimulation gene-2 (sST2) are elevated in heart and pulmonary diseases. However, the relationship of the sST2/interleukin (IL)-33 axis and its triggers as well as its organ distribution is still not known. This study was thus designed to investigate the cellular origin and regulation of sST2 and IL-33 in vitro and in vivo. METHODS AND RESULTS: sST2 and IL-33 gene expression and protein secretion were analysed in pooled organ-specific cDNAs and in primary cell cultures, respectively, by RT-PCR and ELISA technology. The strongest sST2 mRNA expression was detected in heart and lung tissues, which correlated with spontaneous secretion of sST2 protein in vitro. The inflammatory cytokines IL-1alpha, IL-1beta, and tumour necrosis factor alpha as well as supernatants of lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells led to an enhanced secretion of sST2 in cultured cardiac myocytes and lung alveolar epithelial cells. These cytokines enhanced sST2 secretion via an NFkappaB-dependent mechanism. In addition, LPS stimulation in humans in vivo induced a short-term inflammatory response that was followed by a massive enhancement of sST2 secretion. CONCLUSION: These results identify the primary sources and inflammatory triggers for the enhancement of sST2 secretion and demonstrate a relationship between inflammation and the secretion of a bioactive member of the IL-1R family, both in vitro and in vivo.