Curcumins promote monocytic gene expression related to β-amyloid and superoxide dismutase clearance

Neurodegenerative diseases are associated with accumulation of modified proteins or peptides including amyloid-β (Aβ) in Alzheimer's disease (AD), and misfolded superoxide dismutase-1 (SOD-1) in amyotrophic lateral sclerosis (ALS). Clearance of Aβ or SOD-1 by the innate immune system may be important for controlling or preventing disease onset. Curcumins restore Aβ phagocytosis by peripheral blood mononuclear cells (PBMCs) from AD patients and Aβ clearance with upregulation of key genes including MGAT3, vitamin D receptor (VDR) and Toll-like receptors (TLRs). Certain curcumins inhibit inflammatory processes of PBMCs from ALS patients. We developed an in vitro system using human monocytes from patients and monocytic cell lines (i.e. U-937, THP-1) for evaluating curcuminoid potency of innate immune cell stimulation. Bisdemethoxycurcumin and certain analogs potentiated MGAT3,VDR and TLR gene expression 3- to 300-fold in U-937 cells. The effect of curcumins on inflammation in monocytes from patients with ALS was examined. Recursive medicinal chemistry was applied to identify compounds that stimulate the innate immune system for use in the clearance of Aβ in AD and the reversal of neuroinflammation and defective SOD-1 accumulation in ALS.     

Inhibition of kappa opioid receptors attenuated increased cocaine intake in rats with extended access to cocaine

Objective  Previous studies demonstrated that the dynorphin/κ opioid system was up-regulated upon repeated cocaine self-administration. In the present study, we tested the hypothesis that increased cocaine self-administration with extended access was associated with increased activity of the κ opioid system in rats. Materials and methods  Rats self-administered 0.5 mg/kg per injection of cocaine on a fixed-ratio (FR) schedule in either 1-h (short access, ShA) or 6-h (long access, LgA) sessions. After cocaine intake in the LgA rats increased to a maximum, the effects of κ opioid receptor antagonists and a partial agonist were tested on cocaine intake in ShA and LgA rats. Results  Cocaine self-administration increased under FR and progressive-ratio (PR) schedules in LgA rats. Nor-BNI (15–30 mg/kg), a κ receptor antagonist, decreased cocaine intake in LgA rats under a PR schedule (ShA, +1.7%; LgA, −27.4% from baseline), whereas naltrexone (0.3–10 mg/kg) and SG-II-49 (0.025–0.1 mg/kg), a nonspecific opioid receptor antagonist and a partial agonist, respectively, decreased cocaine intake in both groups (PR data: SG-II-49, ShA −28.6%, LgA −19.8%; naltrexone, ShA −34.6%, LgA −11.8% compared with vehicle data). Conclusions  The present study demonstrated that the antagonism of κ opioid receptors attenuated only the increased cocaine intake in LgA rats under a PR schedule, whereas the antagonism of μ and κ receptors decreased cocaine intake in both ShA and LgA groups. The data suggest that increased motivation for cocaine in rats with extended access may be related to increased κ opioid activity and may contribute to compulsive use. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Maintenance of wintertime vitamin D status with cholecalciferol supplementation is not associated with alterations in serum cytokine concentrations among apparently healthy younger or older adults

Epidemiological studies have shown that low vitamin D status results in impaired immune function and is associated with the prevalence of autoimmune and inflammatory conditions. Vitamin D supplementation has been shown to reduce circulating concentrations of inflammatory markers in such conditions. However, the possible beneficial effect of vitamin D supplementation in the general population, particularly for those individuals living at high latitudes where hypovitaminosis D is common during wintertime, remains unclear. The aim of this study was to assess the effect of vitamin D supplementation using doses of 5, 10, and 15 μg/d cholecalciferol (D3) compared with placebo on cytokine concentrations throughout winter in apparently healthy younger (aged 20-40 y) and older (aged ≥64 y) adults. A total of 211 younger and 202 older adults completed the 22-wk intervention (from October to March) with >85% compliance. Serum concentrations of 25-hydroxycholecalciferol [25(OH)D3], high sensitivity C-reactive protein, IL-6, IL-10, soluble CD40 ligand, TGFβ, TNFα, and fibrinogen were measured using ELISA. 25(OH)D3 concentrations significantly decreased in the placebo and 5 and 10/d μg D3 groups in the younger cohort and in the placebo group in the older cohort. Whereas 15 μg/d D3 supplementation maintained 25(OH)D3 concentrations in the younger cohort (baseline, 75.9 nmol/L; postintervention, 69.0 nmol/L) and significantly increased concentrations in the older cohort (baseline, 55.1 nmol/L; postintervention, 73.9 nmol/L), it had no significant effect on cytokine concentrations (ANCOVA, P > 0.05). The long-term effects of low vitamin D status remain to be elucidated and optimization of vitamin D status in otherwise healthy individuals may potentially have lasting beneficial effects on the immune system.     

In Vitro Analysis of Post‐fatigue Reverse‐Torque Values at the Dental Abutment/Implant Interface for a Unitarian Abutment Design

Purpose: This study analyzed baseline and post‐fatigue reverse‐torque values (RTVs) for a specific brand control abutment relative to a third party compatible abutment. The purpose of this study was to compare the abutments’ fatigue resistance to simulated function, using RTVs as an indication of residual preload at the implant/abutment interface. Materials and Methods: Forty Straumann tissue‐level implants were mounted in resin and divided into four groups (n = 10). Forty abutments were seated, 20 control and 20 third‐party abutments, according to manufacturer guidelines. Ten abutments from each manufacturer were evaluated for RTV without fatigue loading, using a calibrated digital torque gauge to provide a baseline RTVs. Fatigue loading was carried out on the remaining ten specimens from each manufacturer according to ISO 14801 guidelines. A moving‐magnet linear motor was used to load one specimen per sequence, alternating from 10 to 200 N at 15 Hz for 5×10⁶ cycles. RTV was recorded post‐fatigue loading. The results were subjected to two‐sample t‐testing and two‐way ANOVA. Scanning electron microphotography was carried out on three specimens from both manufacturers at baseline and post‐fatigue cycling to visualize thread geometry and the abutment/implant interface. Results: The data indicated that mean post‐fatigue RTV observed for the control group was significantly higher than the third‐party group (RTV 42.65 ± 6.70 N vs. 36.25 ± 2.63 N, p= 0.0161). Visual differences at the macro/microscopic level were also apparent for thread geometry, with third‐party abutments demonstrating considerably greater variation in geometrical architecture than control specimens. Conclusions: Within the limitations of this in vitro model, the effect of component manufacturer resulted in a significantly higher RTV in the control group (two‐way ANOVA, p= 0.0032) indicating greater residual preload; however, there was no significant decrease in post‐fatigue RTV for either manufacturer compared to baseline.     

Investigation of structure and function of a catalytically efficient variant of the human flavin-containing monooxygenase form 3.

To characterize the contribution of amino acid 360 to the functional activity of the human flavin-containing monooxygenase form 3 (FMO3) and form 1 (FMO1) in the oxygenation of drugs and chemicals, we expressed four FMO3 variants (i.e., Ala360-FMO3, His360-FMO3, Gln360-FMO3, and Pro360-FMO3) and one FMO1 variant (i.e., Pro360-FMO1) and compared them to wild-type enzymes (Leu360-FMO3 and His360-FMO1, respectively). The amino acid substitutions were introduced into wild-type FMO3 or FMO1 cDNA by site-directed mutagenesis. The thermal stability of variants of Leu360 FMO3 was also studied, and the thermal stability was significantly different from that of wild-type FMO3. The influence of different substrates to modulate the catalytic activity of FMO3 variants was also examined. Selective functional substrate activity was determined with mercaptoimidazole, chlorpromazine, and 10-[(N,N-dimethylaminopentyl)-2-(trifluoromethyl)]phenothiazine. Compared with wild-type FMO3, the Ala360-FMO3 and His360-FMO3 variants were less catalytically efficient for mercaptoimidazole S-oxygenation. N-Oxygenation of chlorpromazine was significantly less catalytically efficient for His360-FMO3 compared with wild-type FMO3. Human Pro360-FMO1 was significantly more catalytically efficient at S-oxygenating mercaptoimidazole and chlorpromazine compared with wild-type FMO1. The data support the mechanism that the Pro360 loci affect thermal stability of FMO3. Because different amino acids at position 360 affect substrate oxygenation in a unique fashion compared with that of FMO3 stimulation, we conclude that the mechanism of stimulation of FMO3 is distinct from that of enzyme catalysis. A molecular model of human FMO3 was also constructed to help explain the results. The increase in catalytic efficiency observed for Pro360 in human FMO3 was also observed when the His of FMO1 was replaced by Pro at loci 360.