The Case for a More Holistic Approach to Dry Eye Disease: Is It Time to Move beyond Antibiotics?

Dry eye disease (DED) is one of the most frequent presentations to optometrists with over 16 million US adults (6.8% of adult population) diagnosed as having this disorder. The majority of associated marketed products offer relief from symptomatology but do not address aetiology. DED harbours many distinguishing features of a chronic inflammatory disorder. The recent explosion in human microbiome research has sparked interest in the ocular microbiome and its role in the preservation and extension of ocular surface health and in the contribution of the gut microbiome to chronic systemic inflammation and associated "Western life-style" diseases. With a significant lack of success for many patients using currently available DED treatments, in this era of the microbiome, we are interested in exploring potential novel therapies that aim to reconstitute healthy bacterial communities both locally and distally (in the gut) as a treatment for DED. Although this direction of investigation is in its infancy, burgeoning interest makes such a review timely. This paper considers a number of studies into the use functional foods and associated products to ameliorate dry eye.

The effect of Blephadex™ Eyelid Wipes on Demodex mites, ocular microbiota, bacterial lipase and comfort: a pilot study.

PURPOSE: To investigate the effect of Blephadex™ Eyelid Wipes on Demodex mites, ocular microbiota, bacterial lipase, tear film characteristics and ocular comfort after one month of daily use. METHODS: Twenty subjects were randomly assigned to use the Blephadex™ Eyelid Wipes on either eye once daily for 30 days whilst the contralateral eye was left untreated in this observer-masked, within-subject study. Demodex count, eyelid bacterial colony count, Tearscope Plus non-invasive tear break up time (NITBUT), Lipiview® tear film lipid layer thickness and phenol red thread test tear volume were measured at baseline and 30 days. Bacterial lipase was quantified from single bacterial colonies using a glycerol monolaurate assay. Ocular comfort was assessed at both visits using the Ocular Surface Disease Index (OSDI) questionnaire and visual analogue scales (VAS) to capture monocular symptoms of itching, dryness and overall discomfort. RESULTS: Six males and 14 females, median age 63.5 (range 48-76) completed the study. A statistically significant reduction in Demodex count was observed in treated eyes only (median ±â€¯IQR: treated eyes 2 ±â€¯3 vs. 0 ±â€¯2, ANOVA p = 0.04). Bacterial colony count, lipase production, NITBUT, lipid layer thickness and tear volume remained unchanged (p > 0.05). Overall comfort improved over time in treated eyes only (15 ±â€¯32 vs. 10 ±â€¯16, p = 0.05). Dryness symptoms significantly reduced in both treated and untreated eyes (23 ±â€¯42 vs. 12 ±â€¯21 and 23 ±â€¯41 vs. 10 ±â€¯15, p = 0.02). The OSDI and ocular itch scores remained unchanged (p > 0.05). CONCLUSION: In this pilot study, no changes were observed in ocular microbiota, tear film characteristics or bacterial lipase in eyes treated with Blephadex™ Eyelid Wipes after one month of daily use in this normal healthy population. Although a statistically significant reduction in Demodex count was observed in treated eyes, overall numbers of Demodex were low. A parallel group, placebo-controlled, randomised clinical trial in a population with active blepharitis is warranted to further elucidate these preliminary findings.

The role of optometrists in India: an integral part of an eye health team.

India has a proud tradition of blindness prevention, being the first country in the world to implement a blindness control programme which focused on a model to address blinding eye disease. However, with 133 million people blind or vision impaired due to the lack of an eye examination and provision of an appropriate pair of spectacles, it is imperative to establish a cadre of eye care professionals to work in conjunction with ophthalmologists to deliver comprehensive eye care. The integration of highly educated four year trained optometrists into primary health services is a practical means of correcting refractive error and detecting ocular disease, enabling co-managed care between ophthalmologists and optometrists. At present, the training of optometrists varies from two year trained ophthalmic assistants/optometrists or refractionists to four year degree trained optometrists. The profession of optometry in India is not regulated, integrated into the health care system or recognised by the majority of people in India as provider of comprehensive eye care services. In the last two years, the profession of optometry in India is beginning to take the necessary steps to gain recognition and regulation to become an independent primary health care profession. The formation of the Indian Optometry Federation as the single peak body of optometry in India and the soon to be established Optometry Council of India are key organisations working towards the development and regulation of optometry.

Role of carnitine in disease.

Carnitine is a conditionally essential nutrient that plays a vital role in energy production and fatty acid metabolism. Vegetarians possess a greater bioavailability than meat eaters. Distinct deficiencies arise either from genetic mutation of carnitine transporters or in association with other disorders such as liver or kidney disease. Carnitine deficiency occurs in aberrations of carnitine regulation in disorders such as diabetes, sepsis, cardiomyopathy, malnutrition, cirrhosis, endocrine disorders and with aging. Nutritional supplementation of L-carnitine, the biologically active form of carnitine, is ameliorative for uremic patients, and can improve nerve conduction, neuropathic pain and immune function in diabetes patients while it is life-saving for patients suffering primary carnitine deficiency. Clinical application of carnitine holds much promise in a range of neural disorders such as Alzheimer's disease, hepatic encephalopathy and other painful neuropathies. Topical application in dry eye offers osmoprotection and modulates immune and inflammatory responses. Carnitine has been recognized as a nutritional supplement in cardiovascular disease and there is increasing evidence that carnitine supplementation may be beneficial in treating obesity, improving glucose intolerance and total energy expenditure.

When east meets west: the relationship between yin-yang and antioxidation-oxidation.

Ancient traditional Chinese medicine (TCM) has effectively relied on the theory of yin-yang balance in diagnoses and treatments of diseases and disorders for more than 2000 years. However, in eastern society, yin-yang is regarded as an incomprehensible ideology without definite physical meaning. Consequently, the yin-yang balance in medicine has not been studied by modern scientific means. In the western world, yin-yang balance is often misunderstood as a religious belief or a principle of lifestyle. Herein, we attempted to define the physical meaning of yin-yang in TCM by correlating it with biochemical processes. We propose that yin-yang balance is antioxidation-oxidation balance with yin representing antioxidation and yang as oxidation. Our proposal is partially supported by the fact that the yin-tonic traditional Chinese herbs have, on average, about six times more antioxidant activity and polyphenolic contents than the yang-tonic herbs. Our hypothesis opens an avenue to systematically study the yin-yang balance and its health implications with the use of modern biochemical tools.

Analysis of antioxidant activities of common vegetables employing oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) assays: a comparative study.

A total of 927 freeze-dried vegetable samples, including 111 white cabbages, 59 carrots, 51 snap beans, 57 cauliflower, 33 white onions, 48 purple onions, 130 broccoli, 169 tomatoes, 25 beets, 88 peas, 88 spinach, 18 red peppers, and 50 green peppers, were analyzed using the oxygen radical absorption capacity (ORAC) and ferric reducing antioxidant capacity (FRAP) methods. The data show that the ORAC and FRAP values of vegetable are not only dependent on species, but also highly dependent on geographical origin and harvest time. The two antioxidant assay methods, ORAC and FRAP, also give different antioxidant activity trends. The discrepancy is extensively discussed based on the chemistry principles upon which these methods are built, and it is concluded that the ORAC method is chemically more relevant to chain-breaking antioxidants activity, while the FRAP has some drawbacks such as interference, reaction kinetics, and quantitation methods. On the basis of the ORAC results, green pepper, spinach, purple onion, broccoli, beet, and cauliflower are the leading sources of antioxidant activities against the peroxyl radicals.