Effects of 3% trehalose as an adjuvant treatment after LASIK

A Preservative-Free Combination of Sodium Hyaluronate and Trehalose Improves Dry Eye Signs and Symptoms and Increases Patient Satisfaction in Real-Life Settings: The TEARS Study

INTRODUCTION

Dry eye disease (DED) is a frequently observed condition characterized by ocular discomfort and visual disturbance. It is highly prevalent and impairs patients' quality of life (QoL). This study assessed the benefit of a preservative-free bioprotectant eye drop formulation containing sodium hyaluronate and trehalose (SH-trehalose) with regards to DED, as well as patient satisfaction, through a large-scale real-life survey.

METHODS

In a multi-center, international, prospective observational study, subjects with DED received SH-trehalose for 84 days. Ocular Surface Disease Index (OSDI), Dry Eye Questionnaire-5 items (DEQ-5), and patient satisfaction were assessed at baseline, day 28, and day 84, and clinical evaluations included ocular surface staining, Schirmer test, tear film break-up time (TBUT), and conjunctival hyperemia at baseline and day 84.

RESULTS

A total of 312 patients were evaluated, of whom 82.4% were women. The mean age was 57.9 ± 15.2 years. The mean OSDI score at baseline was 41.7 ± 20.6. After 84 days, the mean OSDI score was 27.3 ± 19.8 (p < 0.001). The percentage of patients with a severe OSDI score decreased from 60.3 to 34.5%. The DEQ-5 score significantly (p < 0.001) improved after 28 and 84 days, as did patient satisfaction. Ocular surface staining, Schirmer test, TBUT, and conjunctival hyperemia scores improved significantly (all p < 0.001) for both eyes with SH-trehalose between baseline and day 84. Tolerance of SH-trehalose was good.

CONCLUSIONS

SH-trehalose significantly improved the clinical signs and symptoms of DED after 84 days. Moreover, it significantly increased patient satisfaction and was well tolerated.

TRIAL REGISTRATION

NCT04803240.

Tear Film Stabilization and Symptom Improvement in Dry Eye Disease: The Role of Hyaluronic Acid and Trehalose Eyedrops versus Carmellose Sodium

This study evaluated the effectiveness of hyaluronic acid and trehalose (HA/trehalose) eyedrops in managing dry eye disease (DED) symptoms by measuring tear stability and administering a DED questionnaire. Sixty patients were treated with either HA/trehalose eyedrops (Tear A) or carmellose sodium eyedrops (Tear B) as controls. The tear breakup time (TBUT) and non-invasive breakup time (NIBUT) were monitored, and patients completed the standard patient evaluation of eye dryness (SPEED) questionnaire. After two months of twice-daily applications, patients treated with the HA/trehalose eyedrops demonstrated significant improvements in the NIBUT (12.98 ± 3.22 s) and TBUT (12.95 ± 2.98 s), indicating increased tear stability. Moreover, they reported lower dry eye sensation (6.70 ± 4.94 SPEED score points), suggesting a reduction in DED symptoms. These findings underscore the efficacy of HA/trehalose eyedrops in improving both the objective and subjective signs of DED, with twice-daily application enhancing ocular surface conditions and reducing patient-reported symptoms.

Correlation and Level of Agreement between the Ocular Surface Disease Index and the Symptom Assessment in Dry Eye Questionnaires: A Survey-Based Study

PURPOSE

The Ocular Surface Disease Index (OSDI) is the most frequently used dry eye disease (DED) questionnaire, and the Symptom Assessment iN Dry Eye (SANDE) is the simplest and quickest to apply. We analyze the correlation and level of agreement between these two questionnaires in a large DED heterogeneous population to evaluate their performance and potential interchangeability.

METHODS

Prospective, multicenter longitudinal survey-based study performed on patients diagnosed with DED by 99 ophthalmologists from 20/32 Mexican states. Questionnaires were applied in two consecutive visits to analyze the correlation between OSDI and SANDE to evaluate patients with DED clinically. Level of agreement was evaluated with Bland-Altman analysis, and internal consistency of instruments was evaluated individually and combined with Cronbach's alpha index.

RESULTS

3421 patients studied: 1996 (58.3%) women and 1425 (41.7%) men, aged 49.5 ± 15.4 years; 995 (29.1%) patients had aqueous-deficient, 1086 (31.7%) evaporative, and 1340 (39.2%) mixed DED subtypes. Normalized baseline scores were 53.7 (OSDI) and 54.1 (SANDE). After 36.3 ± 24.4 days between visits, scores were reduced to 25.2 (OSDI) and 21.8 (SANDE) points (p < .001). A positive correlation between questionnaires was found at baseline (R = 0.592; p < .001), follow-up (R = 0.543; p < .001) and change between visits (R = 0.630; p < .001). Using both questionnaires together improved the overall reliability of symptom evaluation at baseline (α = 0.7), follow-up (α = 0.7), and both (α = 0.7), compared to individual application (OSDI α = 0.5, SANDE α = 0.6)-the same improvements applied to all DED subtypes. Bland-Altman analysis revealed a differential bias of -0.41% at baseline and +3.6% at follow-up visits between OSDI and SANDE.

CONCLUSIONS

We validated the correlation (high precision) between questionnaires in a large-scale population, demonstrating improved reliability (high accuracy) in evaluating DED when used together, challenging their interchangeable use. These results open a venue to improve recommendations toward a more precise and accurate diagnostic and therapeutic evaluation of DED by using OSDI and SANDE concurrently.

Trehalose versus carboxymethylcellulose oral spray for relieving radiation-induced xerostomia in head and neck cancer patients: a randomized controlled trial

BACKGROUND

The aim of this study was to investigate the effect of trehalose oral spray to relieve radiation-induced xerostomia on a randomized controlled trial (RCT).

METHODS

Prior to RCT, the effect of trehalose (5-20%) on the epithelial growth of fetal mouse salivary gland (SG) explants was evaluated to confirm if 10% trehalose exerted the best epithelial outcomes. Participants who completed radiotherapy for head and neck cancer (HNC) treatment were enrolled in a double-blind RCT, according to inclusion and exclusion criteria as per the CONSORT statement. The experimental group (n = 35) received 10% trehalose spray, while the control group (n = 35) received carboxymethylcellulose (CMC) spray to apply intra-orally 4 times/day for 14 days. Salivary pH and unstimulated salivary flow rate were recorded pre- and post-interventions. The Xerostomia-related Quality of Life scale (XeQoLs) was filled, and scores assessed post-interventions.

RESULTS

In the SG explant model, pro-acinar epithelial growth and mitosis was supported by 10% topical trehalose. As for RCT outcomes, salivary pH and unstimulated salivary flow rate were significantly improved after use of 10% trehalose spray when compared to CMC (p < 0.05). Participants reported an improvement of XeQoLs dimension scores after using trehalose or CMC oral sprays in terms of physical, pain/discomfort, and psychological dimensions (p < 0.05), but not social (p > 0.05). When comparing between CMC and trehalose sprays, XeQoLs total scores were not statistically different (p > 0.05).

CONCLUSIONS

The 10% trehalose spray improved salivary pH, unstimulated salivary flow rate, and the quality-of-life dimensions linked with physical, pain/discomfort, and psychological signs. The clinical efficacy of 10% trehalose spray was equivalent with CMC-based saliva substitutes for relieving radiation-induced xerostomia; therefore, trehalose may be suggested in alternative to CMC-based oral spray.(Thai Clinical Trials Registry; https://www.thaiclinicaltrials.org/ TCTR20190817004).

Current trends in pharmaceutical treatment of Dry Eye Disease: A review

Dry eye disease (DED), keratoconjunctivitis sicca or dysfunctional tear syndrome, is the most prevalent ophthalmic disease which affects a substantial segment of people worldwide with increasing frequency. It is considered a multifactorial disease of the ocular surface and tear film, characterized by a variation of signs and symptoms. The symptoms range from mild to severe itching, burning, irritation, eye fatigue, and ocular inflammation that may lead to potential damage to the cornea, conjunctiva and even vision loss. Correspondingly, depending on the different manifestations and pathophysiology, the treatment must be tailored specifically to each patient by targeting the specific mechanisms implicated in their disease. Currently, there are several medical products and techniques available or under investigation for the treatment of DED. The present article focused on the pathophysiology of DED, the new diagnostic approach and the recently developed drug delivery systems or devices reducing the progress of the disease and treating the causes.

Commercially Available Eye Drops Containing Trehalose Protect Against Dry Conditions via Autophagy Induction

Purpose: Evaluation of marketed eye drops with or without trehalose, a nonreducing natural osmoprotector disaccharide, in autophagy modulation and its role in cell survival during desiccation. Materials and Methods: Eye drops containing either sodium hyaluronate (SH) (Hyabak^®, Thea, France) or a combination of SH with trehalose (Thealose Duo^®, Thea, France) were compared with control conditions to evaluate the ability to modulate autophagy in human epithelial cells in vitro. Autophagy was monitored using LC3, a marker of the autophagic machinery, by fluorescence microscopy and immunoblot analysis. Control and autophagy-deficient cells treated with eye drops were exposed to desiccation to mimic dry eyes and cell survival was evaluated by thiazolyl blue tetrazolium bromide (MTT) assay. Trehalose, a known autophagy inducer was used as a positive control. Results: Artificial tears containing SH with and without trehalose induce a complete autophagic flux, as indicated by an increase in the number of autophagosomes and autolysosomes, and the accumulation of the lipidated form of LC3 associated with complete autophagy. In addition, there was a synergistic effect of SH for autophagy induction when combined with trehalose, compared with each of the components alone. Survival of cells treated with both eye drops and exposed to desiccation was decreased in autophagy-deficient cells, demonstrating the essential role of autophagy on eye drop protection. Conclusions: Autophagic flux is induced by SH-containing eye drops, and this phenomenon is enhanced in combination with trehalose. We also demonstrated that autophagy induction is involved in the osmoprotective effects of both trehalose and SH-containing eye drops, to maintain epithelial cell homeostasis in dry conditions.

The Efficacy and Safety of Trehalose in Primary Trabeculectomy with Mitomycin C: A Report of Early Findings

Objective

To compare bleb morphology and tear tests of glaucoma patients who used trehalose and those who did not use after primary trabeculectomy with mitomycin C (MMC) during the early post-operative period.

Methods

This retrospective study included two groups: Group 1 using Trehalose + hyaluronic acid (THA) after primary trabeculectomy with MMC (n = 19) and Group 2 undergoing primary trabeculectomy with MMC (n = 16). The preoperative and postoperative intraocular pressure (IOP), the results of Schirmer, and tear break-up time tests were analyzed. Postoperative bleb morphology was also evaluated at the 1st day, and 1st and 2nd weeks, and 1st and 2nd months.

Results

There was no statistically significant difference in preoperative IOP, Schirmer test or tear break-up time between groups. The mean horizontal extent of the blebs was significantly wider in Group 1 at the first week (p= 0.02). Bleb vascularization was also found to be lower in Group 1 at the second week (p= 0.001). The mean bleb height and horizontal extent were significantly higher in Group 1 at the first month (p=0.02, p= 0.03, respectively). The mean bleb horizontal extent was significantly higher in Group 1 at the second month (p= 0.03).

Conclusion

The use of trehalose improved surgical success of primary trabeculectomy with MMC in terms of IOP control, post-operative complications, and bleb morphology during the early postoperative period. Trehalose might contribute to wound healing which led to an ideal bleb.

[The effects of a trehalose-based drug used after laser keratorefractive surgeries]

PURPOSE

To analyze the effectiveness of artificial tear drops Thealoz (trehalose 3%) in the correction of dry eye syndrome (DES) after ReLEx SMILE and FEMTO LASIK keratorefractive surgeries.

MATERIAL AND METHODS

The study included 20 patients (40 eyes) who underwent a keratorefractive surgery and were prescribed instillations of Thealoz artificial tear drops for the correction of dry eye syndrome. Patients were divided into 2 group: the 1^st group consisted of 10 patients who underwent ReLEx SMILE surgery, the 2nd group - 10 patients after FEMTO LASIK. The effectiveness of the treatment was evaluated at 1 and 3 months after the surgery using Ocular Surface Disease Index (OSDI), changes in the anterior corneal epithelium (Oxford scale), and tear break-up time (Norn's test).

RESULTS

It was found that the use of artificial tear drops Thealoz regardless of the type of keratorefractive surgery helps reduce discomfort based on the OSDI questionnaire from 10.90±4.55 to 10.20±4.07 and 8.89±3.26 points by 1 and 3 months of the follow-up, respectively (p≤0.05). The degree of epitheliopathy according to the Oxford scale decreases from 0.73±0.75 to 0.25±0.43 points 3 months after the surgery (p≤0.05), which is accompanied by a significant increase in tear break-up time (Norn's test) from 11.18±1.19 to 12.43±1.03 and 12.45±1.03 seconds 1 and 3 months after treatment, respectively (p≤0,05).

CONCLUSION

Complex evaluation of the ocular surface has proved that artificial tear drops Thealoz is effective in reducing DES manifestations after keratorefractive surgery. The results clearly demonstrate that the drug helps increase stability of the tear break-up time, as well as contributes to the decrease in epitheliopathy and subjective discomfort sensations, giving grounds to widen its use in clinical practice.

Autophagy Upregulation by the TFEB Inducer Trehalose Protects against Oxidative Damage and Cell Death Associated with NRF2 Inhibition in Human RPE Cells

Trehalose is a natural dietary molecule that has shown antiaging and neuroprotective effects in several animal models of neurodegenerative diseases. The role of trehalose in the management of age-related macular degeneration (AMD) is yet to be investigated and whether trehalose could be a remedy for the treatment of diseases linked to oxidative stress and NRF2 dysregulation. Here, we showed that incubation of human retinal pigment epithelial (RPE) cells with trehalose enhanced the mRNA and protein expressions of TFEB, autophagy genes ATG5 and ATG7, as well as protein expressions of macroautophagy markers, LC3B and p62/SQTM1, and the chaperone-mediated autophagy (CMA) receptor LAMP2. Cathepsin D, a hydrolytic lysosomal enzyme, was also increased by trehalose, indicating higher proteolytic activity. Moreover, trehalose upregulated autophagy flux evident by an increase in the endogenous LC3B level, and accumulation of GFP-LC3B puncta and free GFP fragments in GFP-LC3 - expressing cells in the presence of chloroquine. In addition, the mRNA levels of key molecular targets implicated in RPE damage and AMD, such as vascular endothelial growth factor- (VEGF-) A and heat shock protein 27 (HSP27), were downregulated, whereas NRF2 was upregulated by trehalose. Subsequently, we mimicked in vitro AMD conditions using hydroquinone (HQ) as the oxidative insult on RPE cells and evaluated the cytoprotective effect of trehalose compared to vehicle treatment. HQ depleted NRF2, increased oxidative stress, and reduced the viability of cells, while trehalose pretreatment protected against HQ-induced toxicity. The cytoprotection by trehalose was dependent on autophagy but not NRF2 activation, since autophagy inhibition by shRNA knockdown of ATG5 led to a loss of the protective effect. The results support the transcriptional upregulation of TFEB and autophagy by trehalose and its protection against HQ-induced oxidative damage in RPE cells. Further investigation is, therefore, warranted into the therapeutic value of trehalose in alleviating AMD and retinal diseases associated with impaired NRF2 antioxidant defense.

Trehalose for Ocular Surface Health

Trehalose is a natural disaccharide synthesized in various life forms, but not found in vertebrates. An increasing body of evidence demonstrates exceptional bioprotective characteristics of trehalose. This review discusses the scientific findings on potential functions of trehalose in oxidative stress, protein clearance, and inflammation, with an emphasis on animal models and clinical trials in ophthalmology. The main objective is to help understand the beneficial effects of trehalose in clinical trials and practice, especially in patients suffering from ocular surface disease. The discussion is supplemented with an overview of patents for the use of trehalose in dry eye and with prospects for the 2020s.

Dry Eye: The Effect of Chi-Ju-Di-Huang-Wan Plus Si Wu Tang and the Underlying Mechanism

Objectives: In this pilot study, the effect of 970 mg Chi-Ju-Di-Huang-Wan (CJDHW) plus 30 mg four-substance decoction (Si Wu Tang; CJDHWSWT) was evaluated, in terms of its ability to alleviate dry eye symptoms and its therapeutic mechanism. Methods: This double-masked prospective investigation has recruited dry eye patients who have been randomly selected into two groups, namely treatment (n = 15) versus nontreatment (n = 15). In the treatment group, a daily oral intake of CJDHWSWT plus eye drops systane ultra was given for 90 consecutive days. In the nontreatment group, only defined eye drops were prescribed. The examinations included Schirmer's test, fluorescein-stained superficial punctate keratitis (SPK), artificial tear consumption, tear vascular endothelium growth factor (VEGF) level, and ocular surface disease index. The drug safety tests included liver and kidney functions, and complete blood counts. The candidates were observed during the screening visit and the following three monthly follow-ups. The data were analyzed by unpaired Student's t-test. Results: Compared to no significance in the nontreatment group, CJDHWSWT significantly (p = 0.03) increased the tear secretion after 3 months of intake. Furthermore, in contrast to no significance in the treatment group, there were significant alterations, including (i) increased fluorescein-stained SPK areas (p = 0.03); (ii) increased artificial tear instillation amount (p = 0.03); (iii) elevated tear VEGF protein levels (p = 0.03) in the nontreatment group; and (iv) significant improvement in clinically relevant phenomenon (e.g., reading limit and uncomfortable feeling in windy conditions), after treatment of artificial tear plus oral intake of CJDHWSWT. As shown by the post-treatment normal defined laboratory data, there were no adverse drug effects. Conclusions: This study has supported that CJDHWSWT is safe and effective in relieving dry eye's clinically relevant symptoms/phenomena. CJDHWSWT avoided the tear VEGF upregulation probably induced by dry eye-associated hypoxia/ischemia.

Clinically Relevant Solution for the Hypothermic Storage and Transportation of Human Multipotent Mesenchymal Stromal Cells

The wide use of human multipotent mesenchymal stromal cells (MSCs) in clinical trials requires a full-scale safety and identity evaluation of the cellular product and subsequent transportation between research/medical centres. This necessitates the prolonged hypothermic storage of cells prior to application. The development of new, nontoxic, and efficient media, providing high viability and well-preserved therapeutic properties of MSCs during hypothermic storage, is highly relevant for a successful clinical outcome. In this study, a simple and effective trehalose-based solution was developed for the hypothermic storage of human bone marrow MSC suspensions for further clinical applications. Human bone marrow MSCs were stored at 4°C for 24, 48, and 72 hrs in the developed buffered trehalose solution and compared to several research and clinical grade media: Plasma-Lyte® 148, HypoThermosol® FRS, and Ringer's solution. After the storage, the preservation of viability, identity, and therapeutically associated properties of MSCs were assessed. The hypothermic storage of MSCs in the new buffered trehalose solution provided significantly higher MSC recovery rates and ability of cells for attachment and further proliferation, compared to Plasma-Lyte® 148 and Ringer's solution, and was comparable to research-grade HypoThermosol® FRS. There were no differences in the immunophenotype, osteogenic, and adipogenic differentiation and the immunomodulatory properties of MSCs after 72 hrs of cold storage in these solutions. The obtained results together with the confirmed therapeutic properties of trehalose previously described provide sufficient evidence that the developed trehalose medium can be applied as a low-cost and efficient solution for the hypothermic storage of MSC suspensions, with a high potential for translation into clinical practice.

[Artificial tear drops Thealoz in the correction of dry eye syndrome after keratorefractive surgery]

PURPOSE

To analyze the effectiveness of artificial tear drops Thealoz (trehalose 3%) in the correction of dry eye syndrome (DES) after keratorefractive surgery based on instrumental monitoring of the condition of eye surface.

MATERIAL AND METHODS

The study included 20 patients (40 eyes) who underwent a keratorefractive surgery and were prescribed instillations of Thealoz artificial tear drops for the correction of dry eye syndrome. Patients were divided into 2 groups: the 1st group consisted of 10 patients who underwent ReLEx SMILE surgery, the 2^nd group - 10 patients after FEMTO LASIK. The effectiveness of the treatment was evaluated at 1 and 3 months after the surgery using conventional instrumental monitoring: tear break-up time (Norn's test), tear film osmolarity test and OCT-meniscometry.

RESULTS

Regardless of the type of surgery, tear film break-up time has significantly increased from 11.16±0.38 sec to 12.95±0.24 (p≤0.05) and 13.85±0.03 (p≤0.05) by months 1 and 3, respectively; it correlated with progressive decrease of tear film osmolarity from 317.29±1.39 to 308.00±0.79 mOsm/L (p≤0.05) at one month, and by the 3^rd month - to 301.75±0.27 mOsm/L (p≤0.05). An improvement in OCT-meniscometry parameters was also observed in the form of a significant increase of the height and depth after 1 and 3 months.

CONCLUSION

The use of artificial tear drops Thealoz contributes to the reduction of DES manifestations after keratorefractive surgery: increased stability of the tear film, restoration of the tear meniscus parameters and tear film osmolarity. The use of trehalose ophthalmic solution is advisable in patients after keratorefractive surgery.

Management of post-LASIK dry eye: a multicenter randomized comparison of a new multi-ingredient artificial tear to carboxymethylcellulose

Purpose

To compare the efficacy and safety of a preservative-free, multi-ingredient formulation of carboxymethylcellulose 0.5%, hyaluronic acid 0.1%, and organic osmolytes (CMC-HA), to preservative-free carboxymethylcellulose 0.5% (CMC) in the management of postoperative signs and symptoms of dry eye following laser-assisted in situ keratomileusis (LASIK).

Methods

This was a double-masked, randomized, parallel-group study conducted in 14 clinical centers in Canada and Australia. Subjects with no more than mild dry eye instilled CMC-HA or CMC for 90 days post-LASIK. Ocular Surface Disease Index^© (OSDI; primary efficacy measure), corneal staining, tear break-up time (TBUT), Schirmer’s test, acceptability/tolerability surveys, and visual acuity were assessed at screening and days 2, 10, 30, 60, and 90 post-surgery. Safety analyses included all enrolled.

Results

A total of 148 subjects (CMC-HA, n=75; CMC, n=73) were enrolled and assigned to receive treatment, and 126 subjects completed the study without any protocol violations. Post-LASIK, dry eye signs/symptoms peaked at 10 days. OSDI scores for both groups returned to normal with no differences between treatment groups at day 90 (P=0.775). Corneal staining, Schirmer’s test, TBUT, and survey results were comparable. Higher mean improvements in uncorrected visual acuity were observed in the CMC-HA group at all study visits, reaching statistical significance at day 30 (P=0.013). Both treatments were well tolerated.

Conclusion

CMC-HA-containing artificial tears relieved post-LASIK ocular dryness as well as CMC alone, and demonstrated incremental benefit in uncorrected vision, with a favorable safety profile. Results support use of CMC-HA eye drops to reduce signs and symptoms of ocular dryness post-LASIK.

Anti-neovascularization effects of DMBT in age-related macular degeneration by inhibition of VEGF secretion through ROS-dependent signaling pathway

Choroidal neovascularization (CNV) is the hallmark of late-staged wet age-related macular degeneration (AMD). Vascular endothelial growth factor (VEGF) is a key component in the development and progression of wet AMD. DMBT, 6,6'-bis(2,3-dimethoxybenzoyl)-α,α-D-trehalose, had been proved that it could suppress tumor angiogenesis and metastasis by inhibiting production of VEGF. But the effects of DMBT on CNV were not known. This study was to investigate effects and mechanisms of DMBT on CNV in vitro and in vivo. Results showed that DMBT could inhibit migration and tube formation of RF/6A cells under ARPE-19 hypoxia conditioned medium. DMBT could reduce lesion area in laser-induced CNV model mice. ELISA and Western blotting assay showed that DMBT markedly inhibited secretion of VEGF in vitro and in vivo. Furthermore, DMBT restrained ROS level under hypoxia via suppressing Nrf2/HO-1 pathway. DMBT effectively suppressed hypoxia-induced the up-regulation of p-Akt, p-NF-κB, and HIF-1α. These results suggest that DMBT can inhibit CNV by down-regulation of VEGF in retina through Akt/NF-κB/HIF-1α and ERK/Nrf2/HO-1/HIF-1α pathway. DMBT might be a promising lead molecule for anti-CNV and serve as a therapeutic agent to inhibit CNV.