Clinical investigation of the protective effects of palm vitamin E tocotrienols on brain white matter.

BACKGROUND AND PURPOSE: Previous cell-based and animal studies showed mixed tocotrienols are neuroprotective, but the effect is yet to be proven in humans. Thus, the present study aimed to evaluate the protective activity of mixed tocotrienols in humans with white matter lesions (WMLs). WMLs are regarded as manifestations of cerebral small vessel disease, reflecting varying degrees of neurodegeneration and tissue damage with potential as a surrogate end point in clinical trials. METHODS: A total of 121 volunteers aged ≥35 years with cardiovascular risk factors and MRI-confirmed WMLs were randomized to receive 200 mg mixed tocotrienols or placebo twice a day for 2 years. The WML volumes were measured from MRI images taken at baseline, 1 year, and 2 years using a validated software and were compared. Fasting blood samples were collected for full blood chemistry investigation. RESULTS: According to per-protocol (88 volunteers) and intention-to-treat (121 volunteers) analyses, the mean WML volume of the placebo group increased after 2 years, whereas that of the tocotrienol-supplemented group remained essentially unchanged. The mean WML volume change between the 2 groups was not significantly different (P=0.150) at the end of 1 year but was significant at the end of 2 years for both per-protocol and intention-to-treat analyses (P=0.019 and P=0.018). No significant difference was observed in the blood chemistry parameters between the 2 groups. CONCLUSIONS: Mixed tocotrienols were found to attenuate the progression of WMLs. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00753532.

Tocotrienols for normalisation of hepatic echogenic response in nonalcoholic fatty liver: a randomised placebo-controlled clinical trial.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is one of the commonest liver disorders. Obesity, insulin resistance, lipid peroxidation and oxidative stress have been identified amongst the possible hits leading to the onset and progression of this disease. Nutritional evaluation of NAFLD patients showed a lower-than-recommended intake of vitamin E. Vitamin E is a family of 8 isoforms, 4 tocopherols and 4 tocotrienols. Alpha-tocopherol has been widely investigated in liver diseases, whereas no previous clinical trial has investigated tocotrienols for NAFLD. Aim of the study was to determine the effects of mixed tocotrienols, in normalising the hepatic echogenic response in hypercholesterolaemic patients with ultrasound-proven NAFLD. METHODS: Eighty-seven untreated hypercholesterolaemic adults with ultrasound-proven NAFLD were enrolled and randomised into control group (n = 44) and tocotrienols group (n = 43). The treatment, either mixed tocotrienols 200 mg twice daily or placebo, had a 1-year duration.Normalisation of hepatic echogenic response, being the trial primary aim, was used in sample size calculations. The data were assessed according to intention to treat principle as primary outcome. Per protocol analysis was also carried out as secondary outcome measurement. RESULTS: Thirty and 34 participants concluded the study in the tocotrienols and placebo group respectively. Alpha-tocopherol levels were within the normal range for all subjects. As primary outcome, the normalisation of hepatic echogenic response was significantly higher for the tocotrienols treated group compared to the placebo group in the intention to treat analysis (P = 0.039; 95% CI = 0.896-6.488). As secondary objective, the per protocol assessment also showed significant rate of remission (P = 0.014; 95% CI = 1.117-9.456). Worsening of NAFLD grade was recorded in two patients in the placebo group, but none in the group treated with tocotrienols. No adverse events were reported for both groups. CONCLUSION: This is the first clinical trial that showed the hepatoprotective effects of mixed palm tocotrienols in hypercholesterolemic adults with NAFLD.

Prevalence of non-alcoholic fatty liver in a hypercholesterolemic population of northwestern peninsular Malaysia.

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide and a frequent finding on ultrasound examination. NAFLD is considered as the liver component of metabolic syndrome and is linked to accelerated atherosclerosis and cardiovascular disease. No data from systematic studies regarding the prevalence of NAFLD are available for the Malaysian population. One hundred eighty untreated hypercholesterolemic volunteers underwent blood and ultrasound examinations to evaluate their livers. NAFLD was diagnosed in 102 subjects (56.7%) with similar prevalences between sexes. Of the 102 positive subjects 82 (80.4%) were graded as mild, 17 (16.7%) as moderate and 3 (2.9%) as severe fatty liver cases. Elevated fasting plasma glucose (FPG) levels were found in 13 of 180 subjects (7.2%), while elevated AST and ALT levels were seen in 30 (16.7%) and 22 (12.2%) of the180 subjects, respectively.

Bioavailability and pharmacokinetic studies of eurycomanone from Eurycoma longifolia.

A validated HPLC analysis of eurycomanone (1), a bioactive quassinoid, in rat plasma following oral and intravenous administration of Eurycoma longifolia Jack extract was developed for pharmacokinetic and bioavailability studies. Relatively high plasma eurycomanone concentrations were detected after an intravenous injection of 10 mg/kg extract F2 containing 1.96 mg/kg of the quassinoid. However, it declined rapidly to zero after 8 h. Its mean elimination rate constant (k(e)), biological half-life (t(1/2)), volume of distribution (V(d)) and clearance (CL) were 0.88 +/- 0.19 h (-1), 1.00 +/- 0.26 h, 0.68 +/- 0.30 L/kg and 0.39 +/- 0.08 L/h/kg, respectively. Following oral administration of eurycomanone, its Cmax and Tmax values were detected as 0.33 +/- 0.03 microg/mL and 4.40 +/- 0.98 h, respectively. The plasma concentration of the quassinoid after oral administration was much lower than after intravenous application in spite of the oral dose being 5 times higher. The results indicate that eurycomanone is poorly bioavailable when given orally. A comparison of the AUC (0-->infinity) obtained orally to that obtained after an intravenous administration (normalized for dose differences) revealed that the absolute bioavailability of the compound was low with 10.5 %. Furthermore, the compound appeared to be well distributed in the extravascular fluids because of its relatively high V(d) value. The poor oral bioavailability was not attributed to instability problems because eurycomanone has been shown to be stable under different pH conditions. Thus, its poor oral bioavailability may be due to poor membrane permeability in view of its low P value and/or high first-pass metabolism.

Determination of plasma testosterone using a simple liquid chromatographic method.

A simple and sensitive high-performance liquid chromatographic (HPLC) method using ultraviolet detection was developed for the determination of testosterone in human plasma. Testosterone and the internal standard, griseofulvin, were extracted from 0.50 ml plasma sample using a mixture of dichloromethane-2,2,4-trimethylpentane (3:2, v/v). The mobile phase, consisted of 0.02 M sodium dihydrogenphosphate-acetonitrile-methanol (51:47:2, v/v) adjusted to pH 3.1 and delivered to a C(18) analytical column (150 x 4.6 mm I.D., 4 microm particles) at a flow-rate of 1 ml/min while the detection wavelength was set at 240 nm with a sensitivity range of 0.005 a.u.f.s. The method has a quantification limit of 1.6 ng/ml. Recoveries of testosterone were all greater than 92% over the linear concentration range of 1.6-400 ng/ml while that of griseofulvin was approximately 95%. The within- and between-day RSD values were all less than 8% while the accuracy values ranged from 96.0 to 106.0% over the concentration range studied. The method was applied to the analysis of early morning plasma testosterone levels of 12 healthy human male volunteers. The levels were found to range from 3.1 to 8.4 ng/ml, within the normal range reported in the literature.