Glaucoma Abstracts 8

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Eye pressure lowering effect of vitamin C
            (Boyd, 1995) Download
Thirty patients (16 men and 14 women) were advised to take three divided doses of vitamin C in capsule form each day until loose stools occured and then back down slightly from this amount (bowel dosage) for a daily intake. Average daily intake for all patients was 10 grams per day. Results: The greatest lowering of pressure was 13 mm as measured with a Goldmann tonometer. The least lowering of pressure was 1 mm. The average for 30 patients was 10 mm. Thirty patients were controlled only with vitamin C. Twenty patients were forced to use eye drops to lower the pressure below 20 mm of mercury as they refused to take vitamin C.

Natural therapies for reducing intraocular eye pressure: Rationale and two case reports
            (Challem, 2002) Download
Elevated intraocular eye pressure is the principal diagnostic risk factor for glau­ coma. People with diabetes have an in­ creased risk of glaucoma, suggesting that this eye disease is influenced by elevated glucose and insulin levels. Adopting a low- glycemic hunter-gatherer Paleolithic diet, as well as taking insulin-sensitizing dietary supplements, can reduce weight and im­ prove glucose tolerance. It is reasonable to assume that such dietary changes may also lower intraocular eye pressure.

Corn silk aqueous extracts and intraocular pressure of systemic and non-systemic hypertensive subjects.
            (George and Idu, 2015) Download
BACKGROUND:  Hypotensive properties have been attributed to the stigma/style of Zea mays L (corn silk). Although the effect of corn silk extract on blood pressure has been documented in animal studies, we are not aware of any study on its effect on human blood pressure and intraocular pressure. METHODS:  A randomised study was carried out on the effect of water only, masked doses of corn silk aqueous extract (60, 130, 192.5 and 260 mg/kg body weight) on intraocular pressure and blood pressure of 20 systemic and 20 non-systemic hypertensive subjects. Intraocular pressure and blood pressure were measured at baseline and every hour for eight hours after administering water or a masked dose of corn silk aqueous extract. Each dose was administered at two-week intervals to each subject in the two study groups. RESULTS:  The results showed that the last three doses of corn silk aqueous extract gave a statistically significant reduction (p < 0.001) in mean intraocular pressure and blood pressure within eight hours of administration. The peak effect on intraocular pressure was observed after four hours and this was preceded by the peak effect on blood pressure, which occurred after three hours of administration. The hypotensive effect was dose-dependent in the two groups. CONCLUSION:  Corn silk aqueous extract has a lowering effect on intraocular pressure in systemic and non-systemic hypertensive subjects. This may have resulted from the fall in blood pressure that is due to potassium-induced natriuresis and diuresis caused by the high potassium content in the high doses of the corn silk extract.

Vitamin D and macular thickness in the elderly: an optical coherence tomography study.
            (Graffe et al., 2014) Download
PURPOSE:  Vitamin D insufficiency is associated with age-related macular degeneration. Our objective was to determine whether low serum 25-hydroxyvitamin D (25OHD) concentration was associated with macular thickness among older adults with no signs of macular dysfunction. METHODS:  Sixty-two French older community-dwellers with no patent macular dysfunction (mean ± SD, 71.2 ± 5.0 years; 45.2% female) included in the Gait and Alzheimer Interaction Tracking (GAIT) study (ClinicalTrials.gov number, NCT01315717) were separated into two groups according to serum 25OHD level (i.e., insufficient < 50 nmol/L or sufficient ≥ 50 nmol/L). The macular thickness was measured on 1000 μm central macula with optical coherence tomography, and further binarized according to normal values of macular thickness (i.e., 267.74 μm for males, and 255.60 μm for females). Age, sex, number of comorbidities, cognitive disorders, body mass index, mean arterial pressure, visual acuity, intraocular pressure, serum calcium concentration and season of testing were considered as potential confounders. RESULTS:  The mean serum 25OHD concentration was 61.2 ± 26.3 nmol/L. Patients with vitamin D insufficiency had a reduced macular thickness compared to those without (232.9 ± 40.4 μm vs. 253.3 ± 32.1 μm, P = 0.042). After adjustment for potential confounders, vitamin D insufficiency was associated with a decreased macular thickness (β = -59.4 μm, P = 0.001). Consistently, the participants with vitamin D insufficiency had a 3.7-fold higher risk of having abnormally low macular thickness compared with those with sufficient 25OHD level (P = 0.042). CONCLUSIONS:  Vitamin D insufficiency was associated with reduced macular thickness among older patients with no patent macular dysfunction. This implies that vitamin D insufficiency may be involved in macular thinning, and provides a scientific base for vitamin D replacement trials in age-related macular degeneration.

Intravenous hypertonic saline to reduce intraocular pressure.
            (Harju et al., 2013) Download
PURPOSE:  To quantitate the effect of intravenous hypertonic saline (IVHTS) injection on elevated intraocular pressure (IOP). METHODS:    Nineteen patients (median age, 65 years; range, 41-84 years) with glaucoma and an IOP 30 mmHg or higher were recruited. A bolus of IVHTS (sodium chloride concentration 23.4%) was injected in an antecubital vein over 10-20 seconds. The IOP and systolic and diastolic blood pressure (BP) were measured frequently for 2 hr. The dosage was 0.5 mmol/kg sodium in 11 patients (Group 1) and 1.0 mmol/kg in eight patients (Group 2). RESULTS:    In both groups, a median absolute IOP reduction of 7 mmHg was achieved in 5 min. The maximum median reduction was 7 mmHg (range, 4-16) and 9 mmHg (range, 3-14) at 5 and 16 min after IVHTS in Group 1 and 2, respectively, at which point the median IOP had reduced from 38 and 35 mmHg to 31 and 27 mmHg (p < 0.001), respectively. In both groups, the IOP remained 7 mmHg reduced 2 hr after IVHTS. Systolic BP increased a median of 14.5 mmHg at 3 min and was comparable with baseline after 6 min. CONCLUSION:  Intravenous hypertonic saline solution reduces IOP moderately within minutes for up to 2 hr.

Calcium, chromium, protein, sugar and accommodation in myopia
            (Lane, 1981a) Download
Persons with increasing myopia statistically invest more diopter-hours in closework accommodation, have abnormal hair concentrations of chromium and calcium, and consume excessive protein and sugar. Myopes, as a class, whether or not their myopia is increasing, statistically are déficient in chromium as measured in nape hair of 120 subjects. Young myopes, ages 7–17, at their greatest period of bone growth and vulnerability to myopic increase, tend to mishandle body calcium significantly more than emmetropes.


Elevation of Intraocular Pressure with Daily Sustained Closework Stimulus to Accommodation Lowered Tissue Chromium and Dietary Deficiency of Ascorbic Acid (Vitamin C)
            (Lane, 1981b) Download
Sustained closework accommodative stimulus results in elevated intraocular pressure (IOP), especially aggravated when tissue chromium is low and vitamin C ingestion does not exceed the US Recommended Daily Allowance. The requirement for tissue chromium in control of IOP is age-related and appears to be essential for sustained accommodation and strong ciliarymuscle function, probably as a co-factor potentiating insulin. IOP elevates as if in an effort to reduce sustained, daily-repeated accommodative stimulus by axial elongation of the eye in the presence of deficient levels of (a) chromium, (b) vitamin C, and (c) binocular-accommodative-amplitude skill-level as measured in terms of Positive Relative Accommodation — measured binocularly with negative lenses at 40 cm from the eyes.

Oral Administration of Forskolin, Homotaurine, Carnosine, and Folic Acid in Patients with Primary Open Angle Glaucoma: Changes in Intraocular Pressure, Pattern Electroretinogram Amplitude, and Foveal Sensitivity.
            (Mutolo et al., 2016) Download
PURPOSE:  To evaluate the effects of a food supplement containing forskolin, homotaurine, carnosine, folic acid, vitamins B1, B2, B6, and magnesium in patients with primary open angle glaucoma (POAG) already in treatment and compensated by intraocular pressure (IOP)-lowering drugs, during a period of 12 months. METHODS:  Twenty-two patients (44 eyes) with POAG, with their IOP compensated by topical drugs, were enrolled and randomly assigned to the food supplement or control treatment group. The additional food supplement treatment consisted in 2 tablets per day (1 in the morning, 1 in the evening) given for 1 year of a balanced association of homotaurine, Coleus forskohlii root extract, l-carnosine, folic acid, vitamins B1, B2, B6, and magnesium. Pattern Electroretinogram (PERG) amplitude, foveal sensitivity obtained with the visual field analyzer frequency doubling technology, and IOP were detected at enrollment (T0), 3 months (T1), 6 months (T2), 9 months (T3), and 12 months (T4). RESULTS:  We observed in treated patients a significant further decrease of IOP and an improvement of PERG amplitude at 6, 9, and 12 months, and foveal sensitivity at 12 months. All values remained substantially stable in control patients. CONCLUSIONS:  The results of the present pilot study indicate that the components of the food supplement reach the eye in a detectable manner, as evidenced by the effects on the IOP. Moreover, they suggest a short-term neuroactive effect, as indicated by the improvement of PERG amplitude and foveal sensitivity in treated, but not in control patients.

Treatment of glaucomatous patients by means of food supplement to reduce the ocular discomfort: a double blind randomized trial.
            (Nebbioso et al., 2013) Download
BACKGROUND AND AIM:  Chronic use of multi-dose eye drops containing preservatives, such as it may happen in patients affected by primary open angle glaucoma, often results in a damage of the ocular surface due to the inherent toxicity of preservatives, that with time may lead to a lacrimal dysfunction syndrome and eye dryness. PATIENTS AND METHODS:  This double blind, randomized, pilot study was conducted on 38 glaucomatous patients suffering from dry eye induced by long-term use of eye drops preserved with BAK. RESULTS:  Treatment of these patients with a food supplement containing an association of forskolin, rutin and vitamins B1 and B2 for 30 days increased significantly their OPI values and improved the symptoms of dry eye with respect to a placebo-treated control group. CONCLUSIONS:  The association of forskolin, rutin and vitamins B1 and B2 appears to be protective for the ocular surface, contributing to restore a normal equilibrium of the tear film in those subjects in which toxic agents such as BAK had determined alterations of its homeostasis.

Oral administration of an association of forskolin, rutin and vitamins B1 and B2 potentiates the hypotonising effects of pharmacological treatments in POAG patients.
            (Pescosolido and Librando, 2010) Download
BACKGROUND/AIMS:  Control of intraocular pressure is still the main strategy to treat glaucoma patients. Forskolin has already shown an ability to control intraocular pressure after topic administration, whereas rutin is known to improve ocular blood fl ow. Therefore, aim of this pilot study has been to observe whether administration of an association of oral forskolin and rutin to POAG patients under different regimens of medical therapy may contribute to their effects, further decreasing IOP values. MATERIALS AND METHODS:  Forskolin (a natural compound present in the crude extract of the plant Coleus Forskohlii) and rutin are the main ingredients of a food supplement commercially available in Italy. In an open label pilot study, 16 patients with POAG under treatment with different topical drugs and with stable IOP were given additional treatment with the food supplement for 40 days, and their IOP values measured at enrolment, at the end of treatment and 40 days after treatment interruption. RESULTS:  Further addition of forskolin and rutin to topical association treatments resulted in a further decrease of IOP by roughly 20% of the initial value. The effect was reversible upon suspension of the treatment. CONCLUSIONS:  These data show for the fi rst time that forskolin and rutin given through the oral route appear to reach the ocular district, where they can act in synergy with topical pharmacological treatments, and contribute to the control of intraocular pressure.

Curcumin: therapeutical potential in ophthalmology.
            (Pescosolido et al., 2014) Download
Curcumin (diferuloylmethane) is the main curcuminoid of the popular Indian spice turmeric (Curcuma longa). In the last 50 years, in vitro and in vivo experiments supported the main role of polyphenols and curcumin for the prevention and treatment of many different inflammatory diseases and tumors.The anti-inflammatory, antioxidant, and antitumor properties of curcumin are due to different cellular mechanisms: this compound, in fact, produces different responses in different cell types. Unfortunately, because of its low solubility and oral bioavailability, the biomedical potential of curcumin is not easy to exploit; for this reason more attention has been given to nanoparticles and liposomes, which are able to improve curcumin's bioavailability. Pharmacologically, curcumin does not show any dose-limiting toxicity when it is administered at doses of up to 8 g/day for three months. It has been demonstrated that curcumin has beneficial effects on several ocular diseases, such as chronic anterior uveitis, diabetic retinopathy, glaucoma, age-related macular degeneration, and dry eye syndrome. The purpose of this review is to report what has so far been elucidated about curcumin properties and its potential use in ophthalmology.

Intravenous glycerol-sodium ascorbate combination as osmotic agent to reduce intraocular pressure.
            (Ray and Thomas, 1977) Download
The present investigation was aimed to study the efficacy of intravenous glycerol 30% with sodium ascorbate 20% as a tension lower​ing osmotic agent. There was effective lowering of intraocular pressure in all the cases, but because of the side effects encountered in majority of the patients, subsequent trials with this drug was not pos​sible.


Oral administration of forskolin and rutin contributes to intraocular pressure control in primary open angle glaucoma patients under maximum tolerated medical therapy.
            (Vetrugno et al., 2012) Download
BACKGROUND:  Tight control of intraocular pressure (IOP) is still the only therapeutic approach available for the treatment of primary open angle glaucoma (POAG). However, some patients do not respond adequately to hypotonising drugs, and despite multiple drug combinations they cannot reach their target IOP. Forskolin is a natural compound that has already shown efficacy in IOP reduction following topical application. PURPOSE:  The aim of this study was to evaluate the effects on the IOP of a food supplement containing forskolin and rutin when administered to POAG patients under maximum tolerated medical therapy (MTMT) and on a waiting list for filtrating surgery to further decrease their IOP. METHODS:  The design of the study was open and case-controlled. Ninety-seven (52 in the treatment group, and 45 in the reference group) patients were enrolled in 8 different glaucoma centers in Italy, all under MTMT and with IOP enrollment values above their target pressure. During the 30 days before surgery, patients in the treatment group were prescribed 2 tablets per day of a food supplement containing rutin and forskolin in addition to their usual topical drug treatment. Their IOP values were measured at 3 time points during the day, at enrollment and once a week until surgery. Control patients continued only with their normal topical therapy. RESULTS:  All patients in the treatment group, independently of the combination drug therapy that they were taking, showed a further 10% decrease (P<0.01) of their IOP, starting from 1 week after introduction of the oral supplement and lasting until the last evaluation before surgery. This decrease was more evident (15% of the enrollment value; P<0.01) in those subjects with high (IOP≥21 mmHg) enrollment values rather than in those with low (IOP<21) enrollment values (9%; P<0.01). On the contrary, IOP values in the control group remained stable from the beginning to the end of the observation period, independently of their enrollment values. CONCLUSIONS:  Forskolin and rutin given as oral treatment appear to contribute to a better control and a further small reduction of IOP in patients who were poorly responsive to multitherapy treatment.


 

References

Boyd, HH (1995), ‘Eye pressure lowering effect of vitamin C’, Journal of Orthomolecular Medicine, 10 (2), 165. PubMed:
Challem, JJ (2002), ‘Natural therapies for reducing intraocular eye pressure: Rationale and two case reports’, Journal of orthomolecular medicine, 17 (4), 209. PubMed:
George, GO and FK Idu (2015), ‘Corn silk aqueous extracts and intraocular pressure of systemic and non-systemic hypertensive subjects.’, Clin Exp Optom, 98 (2), 138-49. PubMed: 25727941
Graffe, A, et al. (2014), ‘Vitamin D and macular thickness in the elderly: an optical coherence tomography study.’, Invest Ophthalmol Vis Sci, 55 (8), 5298-303. PubMed: 25028353
Harju, M, et al. (2013), ‘Intravenous hypertonic saline to reduce intraocular pressure.’, Acta Ophthalmol, 91 (7), 625-29. PubMed: 22834976
Lane, B.C. (1981a), ‘Calcium, chromium, protein, sugar and accommodation in myopia’, Conference on Myopia Copenhagen, 28 141-48. PubMed:
Lane, BC (1981b), ‘Elevation of Intraocular Pressure with Daily Sustained Closework Stimulus to Accommodation Lowered Tissue Chromium and Dietary Deficiency of Ascorbic Acid (Vitamin C)’, Conference on Myopia Copenhagen, 28 149-55. PubMed:
Mutolo, MG, et al. (2016), ‘Oral Administration of Forskolin, Homotaurine, Carnosine, and Folic Acid in Patients with Primary Open Angle Glaucoma: Changes in Intraocular Pressure, Pattern Electroretinogram Amplitude, and Foveal Sensitivity.’, J Ocul Pharmacol Ther, PubMed: 26771282
Nebbioso, M, et al. (2013), ‘Treatment of glaucomatous patients by means of food supplement to reduce the ocular discomfort: a double blind randomized trial.’, Eur Rev Med Pharmacol Sci, 17 (8), 1117-22. PubMed: 23661528
Pescosolido, N and A Librando (2010), ‘Oral administration of an association of forskolin, rutin and vitamins B1 and B2 potentiates the hypotonising effects of pharmacological treatments in POAG patients.’, Clin Ter, 161 (3), e81-5. PubMed: 20589347
Pescosolido, N, et al. (2014), ‘Curcumin: therapeutical potential in ophthalmology.’, Planta Med, 80 (4), 249-54. PubMed: 24323538
Ray, SS and A Thomas (1977), ‘Intravenous glycerol-sodium ascorbate combination as osmotic agent to reduce intraocular pressure.’, Indian J Ophthalmol, 25 (2), 27-30. PubMed: 615147
Vetrugno, M, et al. (2012), ‘Oral administration of forskolin and rutin contributes to intraocular pressure control in primary open angle glaucoma patients under maximum tolerated medical therapy.’, J Ocul Pharmacol Ther, 28 (5), 536-41. PubMed: 22731245