Extract from Aronia melanocarpa, Lonicera caerulea, and Vaccinium myrtillus Improves near Visual Acuity in People with Presbyopia.

Presbyopia is a global problem with an estimated 1.3 billion patients worldwide. In the area of functional food applications, dietary supplements or herbs, there are very few reports describing the positive effects of their use. In the available literature, there is a lack of studies in humans as well as on an animal model of extracts containing, simultaneously, compounds from the polyphenol group (in particular, anthocyanins) and iridoids, so we undertook a study of the effects of a preparation composed of these compounds on a condition of the organ of vision. Our previous experience on a rabbit model proved the positive effect of taking an oral extract of Cornus mas in stabilizing the intraocular pressure of the eye. The purpose of this study was to evaluate the effect of an orally administered ternary compound preparation on the status of physiological parameters of the ocular organ. The preparation contained an extract of the chokeberry Aronia melanocarpa, the honeysuckle berry Lonicera caerulea L., and the bilberry Vaccinium myrtillus (hereafter AKB) standardized for anthocyanins and iridoids, as bioactive compounds known from the literature. A randomized, double-blind, cross-over study lasting with a "wash-out" period of 17 weeks evaluated a group of 23 people over the age of 50, who were subjects with presbyopia and burdened by prolonged work in front of screen monitors. The group of volunteers was recruited from people who perform white-collar jobs on a daily basis. The effects of the test substances contained in the preparation on visual acuity for distance and near, sense of contrast for distance and near, intraocular pressure, and conjunctival lubrication, tested by Schirmer test, LIPCOF index and TBUT test, and visual field test were evaluated. Anthocyanins (including cyanidin 3-O-galactoside, delphinidin 3-O-arabinoside, cyanidin 3-O-glucoside, cyanidin 3-O-rutinoside, cyanidin 3-O-arabinoside) and iridoids (including loganin, sweroside, loganic acid) were identified as substances present in the extract obtained by HPLC-MS. The preliminary results showed that the composition of AKB applied orally does not change visual acuity in the first 6 weeks of administration. Only in the next cycle of the study was an improvement in near visual acuity observed in 92.3% of the patients. This may indicate potential to correct near vision in presbyopic patients. On the other hand, an improvement in conjunctival wetting was observed in the Schirmer test at the beginning of week 6 of administration in 80% of patients. This effect was weakened in subsequent weeks of conducting the experiment to 61.5%. The improvement in conjunctival hydration in the Schirmer test shows the potential beneficial effect of the AKB formulation in a group of patients with dry eye syndrome. This is the first study of a preparation based on natural, standardized extracts of chokeberry, honeysuckle berry, and bilberry. Preliminary studies show an improvement in near visual acuity and conjunctival hydration on the Schirmer test, but this needs to be confirmed in further studies.

The iridoid loganic acid and anthocyanins from the cornelian cherry (Cornus mas L.) fruit increase the plasma l-arginine/ADMA ratio and decrease levels of ADMA in rabbits fed a high-cholesterol diet.

BACKGROUND: Although fruit and vegetable-rich diets have beneficial effects on cardiovascular diseases, we have little knowledge of the impact of fruits and their constituents, iridoids and anthocyanins, on the l-arginine-ADMA-DDAH pathway. Our previous study demonstrated the modulation of those factors by the oral administration of the cornelian cherry fruit. HYPOTHESIS/PURPOSE: We have assessed the effects of the oral administration of two main constituents isolated from the cornelian cherry fruit, iridoid loganic acid and anthocyanins, on l-arginine, its derivatives (ADMA, SDMA), metabolites (DMA, l-citrulline), and the hepatic DDAH activity and its isoform expression in rabbits fed a high-cholesterol diet. We have also analyzed eNOS expression in the thoracic aorta as well as the redox status in blood. STUDY DESIGN: In the present study, we used an animal model of diet induced atherosclerosis. For 60 days, white New Zealand rabbits were fed a standard diet, a 1% cholesterol enriched diet, or concomitantly with the investigated substances. l-arginine, ADMA, SDMA, DMA, and l-citrulline were assessed using the LC-MS/MS method. DDAH activity and redox parameters were analyzed spectrophotometrically. DDAH1 and DDAH2 isoform expressions were assessed by western blotting, mRNA expression of eNOS was quantified by real-time PCR. RESULTS: We demonstrated that the administration of loganic acid (20 mg/kg b.w.), and to a lesser extent of anthocyanins (10 mg/kg b.w.), caused an increase in the l-arginine level and the l-arginine/ADMA ratio. Also, both substances decreased ADMA, DMA, and l-citrulline, but not SDMA levels. Anthocyanins, but not loganic acid, enhanced the activity of DDAH in the liver. Anthocyanins also significantly enhanced both DDAH1 and DDAH2 expression, while loganic acid to a lesser extent enhanced DDAH1 but not DDAH2 expression. Both loganic acid and anthocyanins pronouncedly increased mRNA expression of eNOS in thoracic aortas. Both loganic acid and anthocyanins reversed the blood glutathione level depleted by dietary cholesterol. Cholesterol feeding decreased the blood GPx level, and the change was not reversed by anthocyanins or loganic acid. We did not observe any significant differences in the blood levels of MDA or SOD among the groups. CONCLUSION: Iridoids and anthocyanins may modulate the l-arginine-ADMA pathway in subjects fed a high-cholesterol diet.

Loganic acid and anthocyanins from cornelian cherry (Cornus mas L.) fruits modulate diet-induced atherosclerosis and redox status in rabbits.

BACKGROUND: Cornelian cherry (Cornus mas L.) is a plant growing in southeast Europe, in the past used in folk medicine. There are many previous publications showing the preventive effects of (poly)phenolic compounds, especially anthocyanins, on cardiovascular diseases, but there is a lack of studies comparing the effects of (poly)phenolics and other constituents of fruits. OBJECTIVES: We have attempted to determine if iridoids and anthocyanins from cornelian cherry fruits may affect the formation of atherosclerotic plaques in the aorta as well as lipid peroxidation and oxidative stress in the livers of cholesterol-fed rabbits. MATERIAL AND METHODS: Fractions of iridoids and anthocyanins were analyzed using the high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) methods. Loganic acid (20 mg/kg b.w.) and a mixture of anthocyanins (10 mg/kg b.w.) were administered orally for 60 days to rabbits fed with 1% cholesterol. Histopathological samples of the aortas and the livers were stained with hematoxylin and eosin. Lipid peroxidation (malondialdehyde - MDA) and redox status (glutathione - GSH, glutathione peroxidase - Gpx and superoxide dismutase - SOD) were analyzed using spectrophotometrical methods. RESULTS: Both loganic acid (an iridoid) and a mixture of anthocyanins diminished the formation of atherosclerotic plaques in the aorta. Both substances also diminished lipid peroxidation, measured as a decrease of MDA, and attenuated oxidative stress, measured as an increase of GSH in the livers depleted by cholesterol feeding. Unexpectedly, cholesterol feeding decreased the Gpx activity in the liver, which was reversed by both investigated substances. CONCLUSIONS: We have shown that both iridoids and anthocyanins help prevent fed-induced atherosclerosis, and the consumption of fruits rich in these substances may elicit beneficial effects on the cardiovascular system.

Iridoid-loganic acid versus anthocyanins from the Cornus mas fruits (cornelian cherry): Common and different effects on diet-induced atherosclerosis, PPARs expression and inflammation.

BACKGROUND AND AIMS: Cardiovascular benefits of fruits are attributed mainly to their (poly)phenolic constituents, especially anthocyanins. The main aim of our study is to compare effects of iridoids and anthocyanins from one fruit on diet-induced atherosclerosis. The cornelian cherry is a native or cultivated plant that grows in many European countries, used in cuisine and folk medicine. In our previous study, we showed its constituents and proved that oral administration of lyophilized fruits to hypercholesterolemic rabbits had preventive effects on atherosclerosis through the activation of PPARα expression. In this study, we have compared the effects of the main constituents of the cornelian cherry:iridoid loganic acid and anthocyanins. METHODS: Our experiment followed the model used in our previous study, in which rabbits were fed 1% cholesterol. RESULTS: We showed that both loganic acid (20 mg/kg b.w.) and a mixture of anthocyanins (10 mg/kg b.w.) administered orally for 60 days had a positive impact on dyslipidemia caused by cholesterol-rich diet, although the effects of anthocyanins were more pronounced. Anthocyanins decreased total and LDL-cholesterol and triglycerides and increased HDL-cholesterol. Loganic acid showed similar effects, but only the triglycerides and HDL-cholesterol changes achieved statistical significance. Anthocyanins, and to a lesser extent loganic acid, significantly decreased intima thickness and intima/media ratio in the thoracic aorta. Both substances decrease ox-LDL in the plasma. Anthocyanins significantly increased expression of PPARγ and α in the liver. Loganic acid also increased their expression, but to a lesser extent. Conversely, loganic acid showed pronounced anti-inflammatory effects, decreasing TNF-α and IL-6 activity. CONCLUSIONS: Our results imply that both substances have a positive effect on factors contributing to the development of diet-induced atherosclerosis. Our results also indicate the potential health benefits of fruits containing anthocyanins and iridoids, and support the idea of creating composed phytopharmaceuticals containing both groups of substances.

Application of Cornelian Cherry Iridoid-Polyphenolic Fraction and Loganic Acid to Reduce Intraocular Pressure.

One of the most common diseases of old age in modern societies is glaucoma. It is strongly connected with increased intraocular pressure (IOP) and could permanently damage vision in the affected eye. As there are only a limited number of chemical compounds that can decrease IOP as well as blood flow in eye vessels, the up-to-date investigation of new molecules is important. The chemical composition of the dried Cornelian cherry (Cornus mas L.) polar, iridoid-polyphenol-rich fraction was investigated. Loganic acid (50%) and pelargonidin-3-galactoside (7%) were found as the main components. Among the other constituents, iridoid compound cornuside and the anthocyans cyanidin 3-O-galactoside, cyanidin 3-O-robinobioside, and pelargonidin 3-O-robinobioside were quantified in the fraction. In an animal model (New Zealand rabbits), the influence of loganic acid and the polyphenolic fraction isolated from Cornelian cherry fruit was investigated. We found a strong IOP-hypotensive effect for a 0.7% solution of loganic acid, which could be compared with the widely ophthalmologically used timolol. About a 25% decrease in IOP was observed within the first 3 hours of use.