Histological assessment of intermediate - and long-term creatine monohydrate supplementation in mice and rats

Creatine monohydrate (CrM) supplementation appears to be relatively safe based on data from short-term and intermediate-term human studies and results from several therapeutic trials. The purpose of the current study was to characterize pathological changes after intermediate-term and long-term CrM supplementation in mice [healthy control and SOD1 (G93A) transgenic] and rats (prednisolone and nonprednisolone treated). Histological assessment (18-20 organs/tissues) was performed on G93A mice after 159 days, and in Sprague-Dawley rats after 365 days, of CrM supplementation (2% wt/wt) compared with control feed. Liver histology was also evaluated in CD-1 mice after 300 days of low-dose CrM supplementation (0.025 and 0.05 g · kg^-1 · day^-1) and in Sprague-Dawley rats after 52 days of CrM supplementation (2% wt/wt) with and without prednisolone. Areas of hepatitis were observed in the livers of the CrM-supplemented G93A mice (P < 0.05), with no significant inflammatory lesions in any of the other 18-20 tissues/organs that were evaluated. The CD-1 mice also showed significant hepatic inflammatory lesions (P < 0.05), yet there was no negative effect of CrM on liver histology in the Sprague-Dawley rats after intermediate-term or long-term supplementation nor was inflammation seen in any other tissues/organs (P = not significant). Dietary CrM supplementation can induce inflammatory changes in the liver of mice, but not rats. The observed inflammatory changes in the murine liver must be considered in the evaluation of hepatic metabolism in CrM-supplemented mice. Species differences must be considered in the evaluation of toxicological and physiological studies.

Gender-specific inhibition of platelet aggregation following omega-3 fatty acid supplementation

Background and Aims : Increased platelet aggregation is a major risk factor for heart attacks, stroke and thrombosis. Long chain omega-3 polyunsaturated fatty acids (LCn-3PUFA; eicosapentaenoic acid, EPA; docosahexaenoic acid, DHA) reduce platelet aggregation; however studies in the published literature involving EPA and/or DHA supplementation have yielded equivocal results. Recent in vitro studies have demonstrated that inhibition of platelet aggregation by LCn-3PUFA is gender specific. We examined the acute effects of dietary supplementation with EPA or DHA rich oils on platelet aggregation in healthy male and females.

Methods and Results : A blinded placebo controlled trial involving 15 male and 15 female subjects. Platelet aggregation was measured at 0, 2, 5 and 24 h post-supplementation with a single dose of either a placebo or EPA or DHA rich oil capsules. The relationship between LCn-3PUFA and platelet activity at each time point was examined according to gender vs. treatment. EPA was significantly the most effective in reducing platelet aggregation in males at 2, 5 and 24 h post-supplementation (−11%, −10.6%, −20.5% respectively) whereas DHA was not effective relative to placebo. In contrast, in females, DHA significantly reduced platelet aggregation at 24 h (−13.7%) while EPA was not effective. An inverse relationship between testosterone levels and platelet aggregation following EPA supplementation was observed.

Conclusion : Interactions between sex hormones and omega-3 fatty acids exist to differentially reduce platelet aggregation. For healthy individuals, males may benefit more from EPA supplementation while females are more responsive to DHA.

The effect of folic acid supplementation on dna biomarkers of colorectal cancer risk (uracil misincorporation, global and gene-specific dna hypomethylation) : a randomised intervention study

Background - Alterations in folate status are associated with colorectal carcinogenesis. Folate’s role has been postulated to be either via prevention of changes in DNA methylation or uracil misincorporation.
Objective - To investigate the effect of folic acid supplementation on colonocyte folate status and DNA biomarkers.
Design - Twenty individuals harbouring colonic adenomas were randomised to receive folic acid (600 g daily) or placebo for 6 months post polypectomy. Systemic and colonocyte folate status was determined at baseline and following the intervention. Modified Comet assays were used to determine uracil misincorporation and global DNA hypomethylation at the site adjacent to the polyp and a site distal to the polyp.
Outcomes - Supplementation resulted in increased colonocyte folate, which approached significance, at the site adjacent to the polyp (P= 0.06) but not distal to the polyp (P= 0.36); correspondingly there was a reduction in uracil misincorporation at the site adjacent to the polyp (P = 0.02) and the distal site showed no such trend (P= 0.39). There were no significant changes in global DNA hypomethylation at either site post-intervention.
Conclusions - Folic acid supplementation resulted in increased colonocyte folate and decreased uracil misincorporation at the site of the adenoma but not distal to the adenoma. This supports the hypothesis that localised areas of folate deficiency may exist in human colonic mucosa which respond to folic acid supplementation through increasing colonocyte folate and improving folate-related DNA biomarkers of cancer risk.

Creatine supplementation increases muscle total creatine but not maximal intermittent exercise performance

This study investigated creatine supplementation (CrS) effects on muscle total creatine (TCr), creatine phosphate (CrP), and intermittent sprinting performance by using a design incorporating the time course of the initial increase and subsequent washout period of muscle TCr. Two groups of seven volunteers ingested either creatine [Cr; 6 × (5 g Cr-H2O + 5 g dextrose)/day)] or a placebo (6 × 5 g dextrose/day) over 5 days. Five 10-s maximal cycle ergometer sprints with rest intervals of 180, 50, 20, and 20 s and a resting vastus lateralis biopsy were conducted before and 0, 2, and 4 wk after placebo or CrS. Resting muscle TCr, CrP, and Cr were unchanged after the placebo but were increased (P < 0.05) at 0 [by 22.9 ± 4.2, 8.9 ± 1.9, and 14.0 ± 3.3 (SE) mmol/kg dry mass, respectively] and 2 but not 4 wk after CrS. An apparent placebo main effect of increased peak power and cumulative work was found after placebo and CrS, but no treatment (CrS) main effect was found on either variable. Thus, despite the rise and washout of muscle TCr and CrP, maximal intermittent sprinting performance was unchanged by CrS.

Effect of creatine supplementation on sprint exercise performance and muscle metabolism

The aim of the present study was to examine the effect of creatine supplementation (CrS) on sprint exercise performance and skeletal muscle anaerobic metabolism during and after sprint exercise. Eight active, untrained men performed a 20-s maximal sprint on an air-braked cycle ergometer after 5 days of CrS [30 g creatine (Cr) + 30 g dextrose per day] or placebo (30 g dextrose per day). The trials were separated by 4 wk, and a double-blind crossover design was used. Muscle and blood samples were obtained at rest, immediately after exercise, and after 2 min of passive recovery. CrS increased the muscle total Cr content (9.5 ± 2.0%, P < 0.05, mean ± SE); however, 20-s sprint performance was not improved by CrS. Similarly, the magnitude of the degradation or accumulation of muscle (e.g., adenine nucleotides, phosphocreatine, inosine 5′-monophosphate, lactate, and glycogen) and plasma metabolites (e.g., lactate, hypoxanthine, and ammonia/ammonium) were also unaffected by CrS during exercise or recovery. These data demonstrated that CrS increased muscle total Cr content, but the increase did not induce an improved sprint exercise performance or alterations in anaerobic muscle metabolism.

Theobroma cacao (cocoa) supplementation in the treatment of Non-alcoholic Steatohepatitis

Non-alcoholic Steatohepatitis (NASH) is a chronic disease that results from accumulation of fat within the liver that subsequently stimulates free radicals to damage the cells of the liver. Cocoa is a rich source of antioxidants and it was found that its consumption could slow the development of NASH.

Synthesis, x-ray structure of ferrocene bearing Bis(Zn-cyclen) complexes and the selective electrochemical sensing of TpT

The new ligand, [Fc(cyclen)₂] (5) (Fc=ferrocene, cyclen=1,4,7,10-tetraazacyclododecane), and corresponding Zn^II complex receptor, [Fc{Zn(cyclen)(CH₃OH)}₂](ClO₄)₄ (1), consisting of a ferrocene moiety bearing one Zn^II-cyclen complex on each cyclopentadienyl ring, have been designed and prepared through a multi-step synthesis. Significant shifts in the ¹H NMR signals of the ferrocenyl group, cf. ferrocene and a previously reported [Fc{Zn(cyclen)}]²⁺ derivative, indicated that the two Zn^II-cyclen units in 1 significantly affect the electronic properties of the cyclopentadienyl rings. The X-ray crystal structure shows that the two positively charged Zn^II-cyclen complexes are arranged in a trans like configuration, with respect to the ferrocene bridging unit, presumably to minimise electrostatic repulsion. Both 5 and 1 can be oxidized in 1:4 CH₂Cl₂/CH₃CN and Tris-HCl aqueous buffer solution under conditions of cyclic voltammetry to give a well defined ferrocene-centred (Fc⁰/+) process. Importantly, 1 is a highly selective electrochemical sensor of thymidilyl(3′-5′)thymidine (TpT) relative to other nucleobases and nucleotides in Tris-HCl buffer solution (pH 7.4). The electrochemical selectivity, detected as a shift in reversible potential of the Fc⁰/+ component, is postulated to result from a change in the configuration of bis(Zn^II-cyclen) units from a trans to a cis state. This is caused by the strong 1:1 binding of the two deprotonated thymine groups in TpT to different Zn^II centres of receptor 1. UV-visible spectrophotometric titrations confirmed the 1:1 stoichiometry for the 1:TpT adduct and allowed the determination of the apparent formation constant of 0.89±0.10×10⁶ M⁻¹ at pH 7.4.

Macrocyclic Zn complexes for DNA detection

Researchers from Monash University have developed an electrocatalytic method based on a charge transport through DNA films, which allows detection of complementary over non-complementary and mismatched DNA sequences in fully hybridized duplexes.

The effect of cocoa supplementation on hepatic steatosis, reactive oxygen species and LFABP in a rat model of NASH

Background: Non alcoholic steatohepatitis is hypothesised to develop via a mechanism involving fat accumulation and oxidative stress. The current study aimed to investigate if an increase in oxidative stress was associated with changes in the expression of liver fatty acid binding protein in a rat model of non alcoholic steatohepatitis and whether cocoa supplementation attenuated those changes.

Methods: Female Sprague Dawley rats were fed a high fat control diet, a high fat methionine choline deficient diet, or one of four 12.5% cocoa supplementation regimes in combination with the high fat methionine choline deficient diet.

Results: Liver fatty acid binding protein mRNA and protein levels were reduced in the liver of animals with fatty liver disease when compared to controls. Increased hepatic fat content was accompanied by higher levels of oxidative stress in animals with fatty liver disease when compared to controls. An inverse association was found between the levels of hepatic liver fatty acid binding protein and the level of hepatic oxidative stress in fatty liver disease. Elevated NADPH oxidase protein levels were detected in the liver of animals with increased severity in inflammation and fibrosis. Cocoa supplementation was associated with partial attenuation of these pathological changes, although the severity of liver disease induced by the methionine choline deficient diet prevented complete reversal of any disease associated changes. Red blood cell glutathione was increased by cocoa supplementation, whereas liver glutathione was reduced by cocoa compared to methionine choline deficient diet fed animals.

Conclusion: These findings suggest a potential role for liver fatty acid binding protein and NADPH oxidase in the development of non alcoholic steatohepatitis. Furthermore, cocoa supplementation may have be of therapeutic benefit in less sever forms of NASH.