Effects of cocoa powder and dark chocolate on LDL oxidative susceptibility and prostaglandin concentrations in humans

BACKGROUND

Flavonoids are polyphenolic compounds of plant origin with antioxidant effects. Flavonoids inhibit LDL oxidation and reduce thrombotic tendency in vitro. Little is known about how cocoa powder and dark chocolate, rich sources of polyphenols, affect these cardiovascular disease risk factors.

OBJECTIVE

We evaluated the effects of a diet high in cocoa powder and dark chocolate (CP-DC diet) on LDL oxidative susceptibility, serum total antioxidant capacity, and urinary prostaglandin concentrations.

DESIGN

We conducted a randomized, 2-period, crossover study in 23 healthy subjects fed 2 diets: an average American diet (AAD) controlled for fiber, caffeine, and theobromine and an AAD supplemented with 22 g cocoa powder and 16 g dark chocolate (CP-DC diet), providing approximately 466 mg procyanidins/d.

RESULTS

LDL oxidation lag time was approximately 8% greater (P = 0.01) after the CP-DC diet than after the AAD. Serum total antioxidant capacity measured by oxygen radical absorbance capacity was approximately 4% greater (P = 0.04) after the CP-DC diet than after the AAD and was positively correlated with LDL oxidation lag time (r = 0.32, P = 0.03). HDL cholesterol was 4% greater after the CP-DC diet (P = 0.02) than after the AAD; however, LDL-HDL ratios were not significantly different. Twenty-four-hour urinary excretion of thromboxane B(2) and 6-keto-prostaglandin F(1)(alpha) and the ratio of the 2 compounds were not significantly different between the 2 diets.

CONCLUSION

Cocoa powder and dark chocolate may favorably affect cardiovascular disease risk status by modestly reducing LDL oxidation susceptibility, increasing serum total antioxidant capacity and HDL-cholesterol concentrations, and not adversely affecting prostaglandins.

Determination of quantity and quality of polyphenol antioxidants in foods and beverages

The methods described in this article are quick, simple, and inexpensive to perform. The Folin quantitation method can determine both free and total polyphenol antioxidants in foods and beverages as described, as well as botanical extracts. This assay may also be used to estimate the daily per capita consumption of polyphenols in foods. The dose-response in vitro lower density lipoprotein antioxidant activity measurement (IC50) can be employed to compare antioxidants as pure compounds, or in mixtures after quantitating the polyphenols. The ex vivo lipoprotein-binding antioxidant activity can be measured simply and rapidly to determine possible in vivo binding of pure compounds or extracts from foods. Supplementation and epidemiology studies can utilize the rapid and inexpensive affinity column isolation method of lower density lipoproteins for the determination of lipoprotein oxidative susceptibility.

Red wine does not reduce mature atherosclerosis in apolipoprotein E-deficient mice

BACKGROUND

Red wine polyphenols and ethanol reduce fatty streak formation (early atherosclerosis) in various animal models. These experimental results support the observation that alcoholic beverages protect against myocardial infarction in humans. However, fatty streaks may not reflect the pathology of mature and clinically relevant atherosclerosis. The present study examined the effects of red wine polyphenols and ethanol on mature atherosclerosis in apolipoprotein E-deficient mice.

METHODS AND RESULTS

Eighty-four 7-week-old mice were randomized to receive water, red wine (diluted to 6% ethanol v/v), 6% ethanol v/v, or red wine powder in water. All mice were fed a normal chow diet. At 26 weeks of age, the mice were killed. HDL cholesterol was raised 12.0% (95% CI, 4.0% to 20.0%) and 9.2% (95% CI, 1.5% to 16.9%) by red wine and ethanol, respectively. At the end of study, all mice exhibited advanced atherosclerosis in the aortic bulb, whereas less mature atherosclerosis predominated in the brachiocephalic trunk. The amount of atherosclerosis in the aortic bulb and the brachiocephalic trunk were similar in all groups (P:=0.92 and P:=0.14, respectively). To evaluate whether ethanol or red wine polyphenols were protective by stabilizing atherosclerotic plaques rather than reducing their size, we measured the percentage of collagen-poor areas in left coronary sinus plaques as a morphological criterion of plaque stability. The percentage of collagen-poor areas did not differ between groups (P:=0.71).

CONCLUSIONS

Neither ethanol nor red wine polyphenols reduced mature atherosclerosis or changed the content of collagen in plaques in apolipoprotein E-deficient mice.

Inhibition of moisture penetration to the skin by a novel incontinence barrier product

OBJECTIVE

To measure the ability of a multiple-barrier product to inhibit the passage of a highly water-soluble tracer into the skin when compared with products currently available on the market (Peri-Care; Sween Corp., and Double-Guard; C. R. Bard, Inc.)

DESIGN

Dye extraction from the skin was measured at specified intervals and a spectrophotometric measurement of the amount of dye was obtained.

SETTING AND SUBJECTS

Two groups of light-skinned volunteers, 6 young adults subjects, aged 22 to 31 years, and 6 older subjects, aged 61 to 73 years, were studied in a controlled laboratory setting.

INSTRUMENTS

Spectronic 601 spectrophotometer.

METHODS

Rectangles (1 inch x 4 inch), inscribed on the ventral forearm skin, were divided into 4 1 inch x 1-inch squares, onto which 50 microL of different barrier products were spread. Band-Aids (Johnson & Johnson), saturated with 70 microL of an FD&C red dye No. 40 solution, were placed over the treated squares and left in place for specified intervals up to 8 hours. Similarly treated Band-Aids placed onto untreated skin comprised the controls.

MAIN OUTCOME MEASURE

Amount of dye extracted from the skin as reflected by absorbance spectrophotometry.

RESULTS

This multiple-barrier product inhibited the passage of the tracer into the skin significantly better than the other 2 products at all time points, except for 1 point in the elderly group.

CONCLUSION

Noninvasive preclinical methods show that this prototype barrier cream inhibits the absorption onto the skin of a solution simulating the density and ionic strength of urine. The advantages and limitations of the methods are clarified and directions for clinical research are suggested.

Antiarthritic profile of BF-389--a novel anti-inflammatory agent with low ulcerogenic liability

BF-389, dihydro-4-(3,5-di-tert-butyl-4-hydroxybenzylidene)-2-methyl-2H-1,2- oxazin-3(4H)-one, is a potent, orally active, antiarthritic and analgesic agent with low ulcerogenic potential. A comparison of the activity profiles of BF-389 and naproxen showed similarities in: (1) suppression of developing and chronic adjuvant arthritis (AA); (2) maximal inhibitory response, as shown by the E(max) values in the developing and established AA models; (3) inhibition of bone degenerative changes associated with chronic adjuvant arthritis; and (4) analgesic activity in the acetic acid and phenylquinone writhing assays. Though BF-389 has been shown to be a potent inhibitor of cyclooxygenase, IC50 = 0.84 +/- 0.25 microM against the production of PGE2 in vitro, there is a great difference from most cyclooxygenase inhibitors; it also inhibits the 5-lipoxygenase enzyme. For BF-389, the IC50 for in vitro LTB4 formation was found to be 3.65 +/- 1.19 microM. The ulcerogenic potential of BF-389 was compared to that of naproxen using a five-day in vivo ulcerogenic rat assay. The UD50 for naproxen was found to be approximately 30 mg/kg/day, p.o. Based upon efficacy in the DEV AA and EST AA models, UD50/ED50 values for naproxen were estimated to be 0.7 and 1.9, respectively. For BF-389 the UD50 was shown to be 520 (389-695) mg/kg/day, p.o., and the corresponding UD50/ED50 values were calculated to be 84 and 28, respectively, thus demonstrating the wide margin of safety between efficacy and ulcerogenicity in rats.