METHODS. Subjects consumed daily a formulation containing 10 mg L, 2 mg Z, and 10 mg MZ (active group; n ¼ 53) or placebo (n ¼ 52) for a period of 12 months. Study visits were at baseline, 3, 6, and 12 months. Contrast sensitivity at 6 cycles per degree (cpd) was the primary outcome measure (POM). Secondary outcome measures included CS at other spatial frequencies, best-corrected visual acuity (BCVA), glare disability, photostress recovery, and light scatter. Macular pigment optical density (MPOD) was measured using dual-wavelength autofluorescence, and serum carotenoid concentrations were analyzed using high performance liquid chromatography (HPLC).RESULTS. Compared to placebo, statistically significant improvements from baseline CS were detected at 6 (P ¼ 0.002) and 1.2 (P ¼ 0.004) cpd in the active group. Additionally, improvements in CS were commensurate with the observed increases in retinal concentrations of these carotenoids (r ¼ 0.342, P ¼ 0.002 at 6 cpd). CONCLUSIONS.These results indicate that dietary fortification with the macular carotenoids can have meaningful effects on visual function.

The role of bradykinin B1 receptors in the thermal hyperalgesia following unilateral ultra‐violet (u.v.) irradiation of the hindpaw of rats has been investigated. In non‐irradiated (naive) animals the B1 receptor agonist des‐Arg9‐bradykinin and bradykinin (BK) (up to 1 μmol kg−1 i.v.) had no effect on withdrawal latency to a noxious heat stimulus when administered 60 min before testing. Following exposure of one hindpaw to strong u.v. irradiation the withdrawal latency of the u.v.‐treated paw to radiant noxious heat fell by a maximum of 50% after 48 h. There was no reduction in latency in the contralateral paw. des‐Arg9‐BK (1–100 nmol kg−1 i.v.) administered 24 h after u.v. exposure caused a further dose‐dependent fall (50 ± 4% reduction from saline injected animals at 100 nmol kg−1 i.v.) in withdrawal latency in the u.v.‐treated paw when measured 60 min after injection. The withdrawal latency of the contralateral paw was also reduced but to a lesser extent following des‐Arg9‐BK (100 nmol kg−1 i.v.) with a maximum reduction of 19 ± 3%. Bradykinin also induced a further reduction in withdrawal latency (33 ± 5% reduction at 1 μmol kg−1) although it was not as effective as des‐Arg9‐BK. Bradykinin did not reduce the withdrawal latency in the contralateral paw. The hyperalgesic action of both des‐Arg9‐BK (10 nmol kg−1 i.v.) and bradykinin (100 nmol kg−1 i.v.) were antagonized by the B1 receptor antagonist, des‐Arg9,Leu8‐BK (200 nmol kg−1 i.v.) but not by the B2 receptor antagonist, HOE 140 (0.5 μmol kg−1 i.v.). The results suggest that in conditions of inflammatory hyperalgesia bradykinin B1 receptors are induced both locally and distant to the inflamed area, activation of which leads to further thermal hyperalgesia. In addition, in these conditions bradykinin appears to act predominantly via B1 receptors, presumably after degradation to des‐Arg9‐BK.

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Antioxidant supplementation in patients with nonadvanced age-related macular degeneration results in significant increases in macular pigment and improvements in CS and other measures of visual function. (Clinical trial, http://www.isrctn.com/ISRCTN13894787).

The macular carotenoids lutein (L), zeaxanthin (Z) and meso-zeaxanthin (MZ) accumulate at the macula, where they are collectively referred to as macular pigment (MP). Augmentation of this pigment, typically achieved through diet and supplementation, enhances visual function and protects against progression of age-related macular degeneration. However, it is known that eggs are a rich dietary source of L and Z, in a highly bioavailable matrix. In this single-blind placebo-controlled study, L- and MZ-enriched eggs and control non-enriched eggs were fed to human subjects (mean age 41 and 35 years, respectively) over an 8-week period, and outcome measures included MP, visual function and serum concentrations of carotenoids and cholesterol. Serum carotenoid concentrations increased significantly in control and enriched egg groups, but to a significantly greater extent in the enriched egg group (P<0·001 for L, Z and MZ). There was no significant increase in MP in either study group post intervention, and we saw no significant improvement in visual performance in either group. Total cholesterol increased significantly in each group, but it did not exceed the upper limit of the normative range (6·5 mmol/l). Therefore, carotenoid-enriched eggs may represent an effective dietary source of L, Z and MZ, reflected in significantly raised serum concentrations of these carotenoids, and consequentially improved bioavailability for capture by target tissues. However, benefits in terms of MP augmentation and /or improved visual performance were not realised over the 8-week study period, and a study of greater duration will be required to address these questions.