Use of Ozone-Based Eye Drops: A Series of Cases in Veterinary and Human Spontaneous Ocular Pathologies

Liposomal Ozonated Oil Ensures a Further Reduction in the Microbial Load Before Intravitreal Injection: the "OPERA" Study

INTRODUCTION

This was a prospective study to investigate the antimicrobial efficacy of a novel ophthalmic solution comprising ozonated sunflower oil in liposomes plus hypromellose in conjunction with liposomal foam (BlefOX), in patients undergoing intravitreal injection, in comparison to povidone iodine 5%.

METHODS

The study employed a paired-eye design with n = 195 patients and a total of n = 390 eyes divided into two groups. Conjunctival swabs were collected from both eyes of each patient at baseline (T0-3 days before the injection). The study group underwent home therapy, which included instilling two drops of an isotonic ophthalmic solution containing 0.5% ozonated sunflower oil in liposomes plus hypromellose (Ozodrop) four times daily and applying liposomal foam twice daily to the eye undergoing intravitreal injections. In contrast, the control group (contralateral eyes) received treatment with povidone iodine 5%. This treatment regimen was maintained for 3 days. At T1 (10 min before injection), all patients instilled one drop of a topical solution of povidone iodine 5% into the conjunctival sac of both eyes. After 30 seconds had elapsed, a conjunctival swab was obtained for each eye in both study groups.

RESULTS

The results, derived from conjunctival swabs, exhibited a significant reduction in the microbial load of the study group on both chocolate agar and blood agar (p ≤ 0.007). The study demonstrated that the combination of povidone iodine 5% + Ozodrop + BlefOX provides a greater reduction in microbial load than povidone iodine 5% alone on both chocolate agar (141 [72.31%] vs. 98 [50.26%], p < 0.0001) and blood agar (130 [66.67%] vs. 97 [49.74%], p = 0.0007). The combination of povidone iodine 5% + Ozodrop + BlefOX resulted in the killing of approximately 41% to 49% of bacteria compared to povidone iodine 5% alone on the chocolate agar and blood agar, respectively.

CONCLUSIONS

Liposomal ozonated oil treatment, coupled with liposomal foam, in patients undergoing intravitreal injection led to a substantial reduction in conjunctival microbial load compared to eyes treated solely with povidone iodine 5%.

Liposomal ozonated oil effectiveness in the signs and symptoms of blepharitis in usual clinical practice

PURPOSE

To analyze the efficacy of liposomal ozonated oil (Ozonest®) treatment, in patients with blepharitis or blepharoconjunctivitis, in improving the signs and symptoms of the pathology.

METHODS

Exploratory, open-label, prospective, single-arm, pre-post comparative pilot study in usual clinical practice, in 20 patients with blepharitis/blepharoconjunctivitis, receiving treatment with liposomal ozonated oil, one drop in each eye, 4 times a day, for 28 days. Main purpose was to assess whether there was a clinically improvement in the blepharitis specific BLISS questionnaire score. Changes in the 12-item OSDI, in eyelid signs of blepharitis assessed by the physicians were also evaluated among other tests, and there was also a subjective evaluation of the treatment by patients.

RESULTS

The BLISS score significantly improved from 16.4 before treatment to 11.8 after treatment (p < 0.05). The OSDI score was also significantly improved from 27.5 before treatment to 20.5 after treatment (p < 0.05). All tests conducted before and after treatment showed significant improvement (p < 0.05), except for NIBUT. The treatment received a score of 7 out of 10 by the patients. There were no adverse events in any patient.

CONCLUSION

Liposomal ozonated oil treatment showed good efficacy in improving the signs and symptoms of blepharitis/blepharoconjunctivitis, satisfaction of patients, and good safety and tolerability.

Ozonated Sunflower Oil Embedded within Spray-Dried Chitosan Microspheres Cross-Linked with Azelaic Acid as a Multicomponent Solid Form for Broad-Spectrum and Long-Lasting Antimicrobial Activity

Multicomponent solid forms for the combined delivery of antimicrobials can improve formulation performance, especially for poorly soluble drugs, by enabling the modified release of the active ingredients to better meet therapeutic needs. Chitosan microspheres incorporating ozonated sunflower oil were prepared by a spray-drying method and using azelaic acid as a biocompatible cross-linker to improve the long time frame. Two methods were used to incorporate ozonated oil into microspheres during the atomization process: one based on the use of a surfactant to emulsify the oil and another using mesoporous silica as an oil absorbent. The encapsulation efficiency of the ozonated oil was evaluated by measuring the peroxide value in the microspheres, which showed an efficiency of 75.5-82.1%. The morphological aspects; particle size distribution; zeta potential; swelling; degradation time; and thermal, crystallographic and spectroscopic properties of the microspheres were analyzed. Azelaic acid release and peroxide formation over time were followed in in vitro analyses, which showed that ozonated oil embedded within chitosan microspheres cross-linked with azelaic acid is a valid system to obtain a sustained release of antimicrobials. In vitro tests showed that the microspheres exhibit synergistic antimicrobial activity against P. aeruginosa, E. coli, S. aureus, C. albicans and A. brasiliensis. This makes them ideal for use in the development of biomedical devices that require broad-spectrum and prolonged antimicrobial activity.

A Comparative Study of the Chemical Properties and Antibacterial Activity of Four Different Ozonated Oils for Veterinary Purposes

Infectious skin diseases are quite common in veterinary medicine. These diseases can be caused by both bacteria and pathogenic fungi. Antimicrobial drugs are usually used for treatment. An alternative to these drugs could be ozonated oils with antibacterial and antifungal properties. Four different ozonated oils (linseed, hemp seed, sunflower, and olive) were tested in order to develop an optimal pharmaceutical form for the treatment of skin infections in animals. Chemical parameters such as acid and acidity value, iodine and peroxide value, viscosity, and infrared spectres were analysed. The ozonation of oils resulted in changes in their chemical composition. The antimicrobial activity of the tested oils was evaluated by determining the minimum inhibitory concentrations and zones of inhibition in agar. After ozonation, the acid content increased in all the tested oils. The highest acidity was found in linseed oil (13.00 ± 0.11 mg KOH/g; 6.1%). Hemp oil, whose acidity was also significant (second only to linseed oil), was the least acidified by ozonation (11.45 ± 0.09 mg KOH/g; 5.75%). After ozonation, the iodine value in oils was significantly reduced (45-93%), and the highest amounts of iodine value remained in linseed (47.50 ± 11.94 g Iodine/100 g oil) and hemp (44.77 ± 1.41 Iodine/100 g oil) oils. The highest number of peroxides after the ozonation of oils was found in sunflower oil (382 ± 9.8 meqO2/kg). It was found that ozonated hemp and linseed oils do not solidify and remain in liquid form when the temperature drops. The results showed a tendency for the reference strains of S. aureus, E. faecalis, and E. coli to have broader zones of inhibition (p < 0.001) than clinical strains. Overall, ozonated linseed oil had the highest antibacterial activity, and ozonated olive oil had the lowest, as determined by both methods. It was found that ozonated linseed oil was the most effective on bacteria, while the most sensitive were S. aureus ATCC 25923, MRSA, and S. pseudointermedius (MIC 13.5 mg/mL, 4.6 mg/mL, and 13.5 mg/mL, respectively, and sterile zones 20.67 ± 0.98 mm, 20.25 ± 0.45 mm, and 18.25 ± 0.45 mm, respectively). The aim and new aspect of this work is the characterisation of selected ozonated vegetable oils, especially hemp oil, according to chemical and antibacterial parameters, in order to select suitable candidates for preclinical and clinical animal studies in the treatment of bacterial or fungal skin infections in terms of safety and efficacy.

In praise of povidone-iodine application in ophthalmology

Polyvinyl pyrrolidone or povidone-iodine (PVP-I) is a water-soluble complex formed by the combination of iodine and a water-soluble polymer, polyvinyl pyrrolidone. This complex exerts bactericidal, fungicidal, and virucidal action by gradually releasing free iodine at the site of application to react with pathogens. In ophthalmology, PVP-I is used as a disinfectant and antiseptic agent for preoperative preparation of the skin and mucous membranes and for treating contaminated wounds. PVP-I has been shown to reduce effectively the risk of endophthalmitis in various ocular procedures, including cataract surgery and intravitreal injections; however, it has also been used in the treatment of conjunctivitis, keratitis, and endophthalmitis, with promising results especially in low-resource situations. PVP-I has been associated with complications such as postoperative eye pain, persistent corneal epithelial defects, ocular inflammation, and an attendant risk of keratitis. In cases of poor PVP-I tolerance, applying PVP-I at lower concentrations or using alternative antiseptics such as chlorhexidine should be considered. We provide an update on the efficacy of PVP-I in the prophylaxis and treatment of conjunctivitis, keratitis, and endophthalmitis and a comprehensive analysis of the current literature regarding the use of PVP-I in the management of these ocular conditions. Also, PVP-I-related adverse effects and toxicities and its alternatives are discussed. The goal is to present a thorough evaluation of the available evidence and to offer practical recommendations for clinicians regarding the therapeutic usage of PVP-I in ophthalmology.

Ozonated saline intradermal injection: promising therapy for accelerated cutaneous wound healing in diabetic rats

Introduction

The use of ozonized water is gaining importance in medicine due to its effects on hyperglycemia and wound healing mechanisms.

Methods

This experiment was conducted to assess the impacts of intradermal administration of ozonated water on acute skin wound healing in a diabetic rat model. Sixty-four adult male Wistar rats were randomly divided into two groups: an ozonated water group (O3W) and a control group (CG). Experimental diabetes was chemically induced in the rats by the intraperitoneal administration of 60 mg/kg streptozotocin. One week later, full-thickness skin surgical wounds (1 cm2) were created between the two shoulders of the rats under general anesthesia. The wounds were then daily irrigated with normal saline (CG) or intradermally injected with 1 mL of ozonated water at 10 mg/L O3W. Wound healing was evaluated through macroscopic analysis, measuring wound size, diameter, and percentage of contraction rate before wounding and at 3, 7, 9, 12, 14, 18, 21, 24, and 28 days post-wounding. On days 7, 14, 21, and 28 after induction of the wounds, the body weights and blood glucose levels of rats (8 per group) were measured before the rats were euthanized. Moreover, the morphological structure of the tissue, vascular endothelial and transforming growth factor (VEGF and TGF) affinity and gene expression were examined.

Results

The O3W group had significantly lower blood glucose levels and wound size and gained body weight. Additionally, epithelial vascularization, stromal edema, TGF, and VEGF gene expression significantly improved in the O3W group.

Discussion

Therefore, ozonated water has the potential to enhance and promote cutaneous wound healing in diabetic rats.

Ozonated Oil in Liposome Eyedrops Reduces the Formation of Biofilm, Selection of Antibiotic-Resistant Bacteria, and Adhesion of Bacteria to Human Corneal Cells

The recent attention to the risk of potential permanent eye damage triggered by ocular infections has been leading to a deeper investigation of the current antimicrobials. An antimicrobial agent used in ophthalmology should possess the following characteristics: a broad antimicrobial spectrum, prompt action even in the presence of organic matter, and nontoxicity. The objective of this study is to compare the antimicrobial efficacy of widely used ophthalmic antiseptics containing povidone-iodine, chlorhexidine, and liposomes containing ozonated sunflower oil. We determined the minimum inhibitory concentration (MIC) on various microbial strains: Staphylococcus aureus (ATCC 6538), methicillin-resistant Staphylococcus aureus (ATCC 33591), Staphylococcus epidermidis (ATCC 12228), Pseudomonas aeruginosa (ATCC 9027), and Escherichia coli (ATCC 873). Furthermore, we assessed its efficacy in controlling antibiotic resistance, biofilm formation, and bacterial adhesion. All three antiseptic ophthalmic preparations showed significant anti-microbicidal and anti-biofilm activity, with the liposomes containing ozonated sunflower oil with the highest ability to control antibiotic resistance and bacteria adhesion to human corneal cells.

Prophylaxis of Ocular Infection in the Setting of Intraocular Surgery: Implications for Clinical Practice and Risk Management

In this review we discuss the role of intraocular surgery preoperative prophylaxis. The correct choice of antimicrobial drug is variable in each surgical setting, according to the available strengths of evidence, the anatomical district involved, and the type of procedure. In the ophthalmic surgical field, there has been a progressive shift from antibiotic formulations, which are known to cause antibiotic resistance, to a new class of antiseptic compounds, which proved to be effective not only against bacteria, but also against fungi, protozoa, and viruses. Among these, povidone-iodine (PVI) is a water-soluble polymer that can form a complex with iodine, and the perioperative application of PVI 5-10% eye drop for 3 min is the gold standard for infection prophylaxis. A new formulation of 0.6% PVI eye drop is a new option for infection prophylaxis in the days before surgery. Chlorhexidine is a biguanide compound, which is a valid alternative with a good safety and efficacy profile and is the antiseptic of choice in patients with iodine allergy. New compounds that are currently being studied include polyhexamethylene biguanide (PHMB), picloxydine, ozone, hypochlorous acid (HOCl), and Biosecur. PHMB is a biguanide polymer that was found to be more effective than PVI in in vitro studies for reducing microorganisms and extending the duration of antisepsis, but to date, there are no formulations available on the market for preoperative ocular surgery in which it is present as main ingredient. Ozone is a molecule with oxidizing effect, which showed interesting preliminary results but is not effective against virus, Staphylococcus aureus and Candida albicans. HOCl has a natural bactericidal propriety but its applicability to prophylaxis of ocular infection in the setting of ocular surgery is not established. Biosecur is a non-toxic organic alcohol-free compound that exhibited bactericidal and fungicidal effect versus all common microorganisms and is currently available as an ocular spray.

Effects of ozone therapy on acidic corneal burns in rats

In the present study the effect of ozone therapy on hydrofluoric acid (HFA) related eye burn was investigated in rats. A Total 20 healthy male Wistar albino rats (weighing 250 - 300 g with the age of 16 weeks) were used. They were divided into groups (experimental and control groups) of 10 rats being housed individually and fed ad libitum. The HFA (2.00%) burn was created in all animals. The ozonized (20.00 µg O₃ mL^-1) bi-distilled water was applied as a drop (10.00 µL each drop) every 8 hr for 7 days in the experimental group. At the same time, 0.90% NaCl was applied as drop (10.00 µL each drop) every 8 hr for 7 days in the control group. In the experimental group, intensive inflammation, angiogenesis, epithelial damage and stromal edema were detected in one animal. Epithelial vascularization and stromal edema were seen in four animals. In control group, only two animals' corneal structures were normal. Inflammation, angiogenesis, epithelial damage, fibrosis, epithelial vascularization and stromal edema were detected in the rest. As a result of this study, it was observed that local usage of ozone therapy had a positive effect on the healing of corneal burns caused by HFA. It was concluded that more ozone-related studies should be done to enlighten the subject.

Safety and tolerability of ozonated-oils in liposome eyedrop in preterm eye examination

BACKGROUND

Eye examinations for ROP screening in preterm newborns are characterized by two main problems: infection control and poor tear secretion. Therefore, in order to reduce the risk of ocular infection and to protect the ocular surface, netilmicin eye drops are usually used after the exams. The purpose of our study was to evaluate the safety and tolerability of ozonated-oils eyedrops during the eye examination of preterm babies in the screening for ROP, sparing the use of antibiotics eyedrops.

METHODS

All newborn infants that needed to be screened for ROP were divided into two groups: in group A we used topical netilmicin eye drops and in group B ozonated-oils eyedrops. We looked for any sign of conjunctival injection and chemosis, infectious conjunctivitis, blepharoconjunctivitis, erythema, and edema of the eyelids.

RESULTS

A total of 162 adverse effects out of 3546 examinations (4,5%) were reported acutely: in group A (1778 examinations), they consisted of 47 reactive conjunctivitis, 3 cases of blepharoconjunctivitis, 30 of eyelids swelling, and 3 infectious conjunctivitis, compared to 39 cases of conjunctival injection, 3 blepharoconjunctivitis, 33 eyelids swelling and 4 infectious conjunctivitis in group B (1768 examinations). No significant differences were found in the comparison of the two groups.

CONCLUSIONS

Ozonated-oils eyedrops should be considered a valid and safe alternative for the lubrification of the ocular surface and an adjuvant strategy to further minimize the risk of microbial contamination during screening for ROP.

In Vitro efficacy of cyclosporine a and various antiseptics and antiviral drugs on adenovirus genotype 8, a common cause of epidemic keratoconjunctivitis

PURPOSE

To evaluate the in vitro efficacy of cidofovir, ganciclovir, povidone-iodine, chlorhexidine, and cyclosporine A on adenovirus genotype 8.

METHODS

Conjunctival samples were collected from patients with adenoviral conjunctivitis and cultured in A549 cells. Adenovirus diagnosis was confirmed by RT-PCR. For each drug, the 50% cytotoxic concentration (CC 50 ) was determined. Subsequently, the antiviral activity was tested at concentrations below CC 50, and the 50% inhibitor concentration (IC 50 ) of drugs was determined RESULTS: While the IC 50 of cidofovir against adenovirus genotype 8 was 3.07 ± 0.8 µM, ganciclovir, povidone-iodine, chlorhexidine, and cyclosporine A were not found to be effective against adenovirus genotype 8 at concentrations below the CC 50 value.

CONCLUSIONS

Cidofovir was found effective and the IC 50 value was within the ranges in the literature. Ganciclovir and cyclosporine A were found to be ineffective at doses below the cytotoxic dose, povidone-iodine and chlorhexidine was found to be highly cytotoxic.

Ophthalmic Solutions with a Broad Antiviral Action: Evaluation of Their Potential against Ocular Herpetic Infections

HSV-1 can be associated with severe and recurrent eye infections characterized by a strong inflammatory response that leads to blepharoconjunctivitis, epithelial and stromal keratitis, and retinal necrosis. The incidence of HSV-1 keratitis is 1.5 million every year worldwide, including more than 40,000 new cases exhibiting serious visual failures. Generally, the therapy uses antiviral drugs to promote healing; however, there are currently no compounds that are able to completely eradicate the virus. In addition, the phenomenon of resistance is rapidly spreading among HSV-1 strains, creating mutants developing resistance to the common antiviral drugs; therefore, deep research on this issue is warranted. The efficacy of different ophthalmic solutions already on the market was evaluated for reducing HSV-1 infection. Different plaque assays were set up on epithelial cells, revealing that two ophthalmic solutions were able to inhibit viral replication in the early stages of infection. The data were further confirmed by molecular tests analyzing the expression levels of the principal genes involved in HSV-1 infection, and a strong reduction was observed after only 1 min of eye-drop treatment. Collectively, these results suggested the use of ophthalmic solutions as potential antiviral options for the treatment of ocular herpetic infection.

In vitro antimicrobial activity of ozonated oil in liposome eyedrop against multidrug-resistant bacteria

Bacteria are the most common causative agents of ocular infections. Treatment with topical broad-spectrum antibiotics is recommended in severe cases. However, antibiotic resistance has become a major concern in recent years, although antibiotics are generally effective in treating ocular infections. Antibacterial compound screening is performed to identify alternative therapeutic options to antibiotics. The aim of this study was to assess the in vitro antimicrobial activity of an ophthalmic solution containing ozonated oil. Strains of bacterial species with a multidrug resistance profile, which are responsible for a large proportion of ocular infections, were isolated and selected from different biological samples. The bacterial isolates were cultured, and ozonated oil was used to evaluate the inhibition zones at different time points. The treatment exhibited antibacterial activity against all the tested species. The effect was lower against the strains of Pseudomonas aeruginosa and more evident against Staphylococcus and Streptococcus spp. Our results suggest that the administration of ozonated oil may be a candidate agent to treat some infections of the ocular surface with a potential role in antimicrobial prophylaxis.

Liposomal Ozonated Oil in Ocular Infections: A Review of Preclinical and Clinical Studies, Focusing on Its Antiseptic and Regenerative Properties

Ozonated oil has shown antimicrobial, anti-inflammatory and regenerative properties that make it useful in the prevention of infectious diseases and also as an adjuvant in wound-healing management. This review brings together most aspects of the use of liposomal ozonated oil for ocular infections and regeneration of the ocular surface. A search was performed in PubMed, Medline, Web of Science and Cochrane Library for studies published by June 2021. Search terms were combined to sort out papers on the properties and use of ozonated oil in ocular infections. A total of 25 publications were selected for this review on the composition, mechanism of action, restorative action, and preclinical and clinical studies of liposomal ozonated oil focused on ocular infections. In patients with complicated corneal pathology, liposomal ozonated oil has been found to restore corneal ulcers and improve keratitis. In patients with ocular pathologies involving inflammation and infections, liposomal ozonated oil has been found to improve and almost completely restore the signs of vernal, granulomatous and even adenoviral conjunctivitis. Liposomal ozonated oil has also been found to be effective in reducing ocular microbial flora. In conclusion, liposomal ozonated oil has an antiseptic and regenerative effect on corneoconjunctival tissues. It has demonstrated efficacy and safety profile for its use in ocular infections and can be considered as a suitable supportive strategy both alone and combined with other antimicrobial agents.

Riboflavin/UV-A corneal phototherapy as stand-alone management of ulcerative keratitis in dogs

Corneal ulcers are one of the most common ocular disorders in veterinary ophthalmology and several factors can negatively influence the efficacy of the currently available therapeutic options, leading to a loss of corneal transparency and, thus, vision. Twenty-five dogs with clinical signs of corneal ulcers were randomised to receive either corneal phototherapy (16 dogs; study group) or topical standard medical therapy (9 dogs; control group). The riboflavin/UV-A corneal phototherapy (PACK-CXL) consisted in the application of a riboflavin ophthalmic solution (Visioflavin®; Vision Engineering Italy srl, Rome, Italy) onto the cornea for 20 min followed by 30 mW/cm2 UV-A irradiance for 3 min using a point-of-care UV-A device (Vetuvir®; Vision Engineering Italy srl, Rome, Italy). The complete healing of the ulcerative lesion was defined as the complete restoration of the corneal epithelial integrity with negative fluorescein staining. The corneal phototherapy achieved complete corneal healing in all the dogs by 20.5 ± 7.8 days. In the control group, only two dogs achieved complete healing by 21.5 ± 15.6 days. This intervention may represent a valid option to hasten corneal wound healing and a clinical resolution of ulcerative keratitis in dogs.

Effectiveness of liposomal ozonized oil in reducing ocular microbial flora in patients undergoing cataract surgery

PURPOSE

To evaluate the antimicrobial effectiveness of a liposomal ozonized oil solution used as a home therapy in patients undergoing cataract surgery. Antimicrobial efficacy was evaluated as the reduction in the bacterial load of the most common bacteria isolated from cases with endophthalmitis.

SETTING

20 Italian experimental centers of the Effectiveness of Liposomal Ozonized oil on Ocular Microbial flora before cataract surgery study group.

DESIGN

Interventional, nonrandomized, paired-eye designed, phase 4 clinical study.

METHODS

A total of 174 patients undergoing cataract surgery were divided into 2 groups: the study group (174 eyes) underwent surgery and received an isotonic ophthalmic solution of 0.5% ozonized oil in liposomes plus hypromellose treatment (2 drops 4 times/d), and the control group (174 contralateral eyes) was treated with saline solution. The treatment lasted for 3 days. Subconjunctival swabs were taken from both eyes of each patient at T0 (the day before starting the treatment and 4 days preoperatively) and at T4 (after 3 days of treatment and 10 min preoperatively) and sent to the laboratory within 24 hours of collection for microbiological analysis.

RESULTS

30% of 696 swabs taken at T0 were sterile. Contaminated swabs had a high prevalence of coagulase-negative staphylococci, including Staphylococcus epidermidis, and more than 60 different bacterial species were isolated. A significant reduction in microbial load was observed after treatment (>90% of the samples). The microbial load in the control group remained unchanged.

CONCLUSIONS

Liposomal ozonized oil reduced the microbial burden after topical administration in a large study population.

Antibiofilm and repair activity of ozonated oil in liposome

The use of medical devices, such as contact lenses, represents a substantial risk of infection, as they can act as scaffolds for formation of microbial biofilms. Recently, the increasing emergency of antibiotic resistance has prompted the development of novel and effective antimicrobial drugs for biofilm treatment, such as oxidizing agents. The purpose of this study is to investigate the effects of Ozodrop® and Ozodrop® gel, commercial names of ozonated oil in liposomes plus hypromellose, on eradication and de novo formation of biofilms on different supports, such as plastic plates and contact lens. Our results demonstrate that ozonated liposomal sunflower oil plus hypromellose have an excellent inhibitory effect on bacterial viability and on both de novo formation and eradication of biofilms produced on plates and contact lens by Pseudomonas aeruginosa and Staphylococcus aureus. Moreover, we show that Ozodrop® formulations stimulate expression of antimicrobial peptides and that Ozodrop® gel has a strong repair activity on human epithelial cells, suggesting further applications for the treatment of non‐healing infected wounds.

Studies on the Effectiveness of Ozone Therapy on the Treatment of Experimentally Induced Keratitis with Candida albicans in Rabbits

PURPOSE

In the present study, antifungal activity of ozonated olive oil (OZO) and ozonated distilled water (ODW) in the treatment of experimentally induced keratitis with C. albicans in rabbits were investigated.

METHODS

The Groups were composed of as 1, 2, 3, 4, 5, 7 (n = 5 rabbits, 10 eyes/in each group) and Group 6 (n = 10 rabbits, 20 eyes/in the group). Fourty-eight hours after C. albicans inoculation; Group 1 received fluconazle (FLU)+OZO drops, Group 2 received FLU drop, Group 3 received OZO drop, Group 4 received FLU+ODW drops, Group 5 received ODW drop, Group 6 (infected control group) and Group 7 received PBS drop (negative control group). Treatment continued in all groups for 22 days for every 8 hours.

RESULTS

Cornea cultures made 24 days post inoculation revealed statistically significant differences (p < 0,05) with concern to C. albicans amounts between Group 6 and Group 1-5. Statistical comparison of corneal opacity and corneal ulcer and conjunctivitis values among the Group 6 and Group 1-5 were also different significantly (p < 0,05) on days 20 and 24 post inoculation.

CONCLUSION

OZO and ODW were found to be effective in treating C. albicans keratitis in the present study. It has also been proven by this study that ODW contain 26 μg/ml was the most effective in the treatment of C. albicans keratitis.

Ozone and its derivatives in veterinary medicine: A careful appraisal

The therapeutic use of ozone and its derivatives in the veterinary medicine it is still in an emergent stage. Gaseous ozone chemical instability makes necessary its extemporaneous preparation and the accordance about ozone treatments with the highest quality standards in publications is of paramount importance. Moreover, the numerous method of administration in different animal species, the prevalence of case reports, the deficiency of consistent evaluation of the outcomes, as well as the lack of standardization of the treatment operating procedures represents an open question for its spreading and official approval. The keywords "ozone", "ozonated", "ozonation" "ozonized", "ozonization", "oxygen-ozone therapy", "veterinary", "pets", "animal" were used to perform a literature review using PubMed, Cochrane, Google Scholar, Zotero databases with the temporal restriction for published manuscripts starting from 2010. All the researches were critically evaluated, regardless of the impact factor, if any, of the journals in which they were presented. The deepening of the mechanisms of action of this bio-oxidative therapy can open new horizons on its use. The distinctive condition to achieve such a scenario is an improved knowledge of the qualitative/quantitative characteristics of ozone and its derivatives. All with the aim of taking nothing away to the cited original research papers, but of improving the promising therapeutic implications of ozone therapy in veterinary medicine as a standardization stimulus about this therapeutic resource with multiple application specificities.

COVID-19 Ocular Prophylaxis: The Potential Role of Ozonated-Oils in Liposome Eyedrop Gel

Purpose

To assess whether ozonated-oil in liposome eyedrop gel (OED) could be used to prevent the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection in an in vitro infection model.

Methods

First, we tested the efficacy of OED on in vitro cell regeneration and dry eye resolution in human corneal epithelial cells (hCE-2). Second, we assessed the in vitro anti-SARS-CoV-2 infection efficacy of OED using Vero E6 cells. Tissues were examined to assess different parameters: morphology, histology, and mRNA expression at 24 hours after treatment.

Results

OED could restore 50% of the scratch in the monolayer of hCE-2 cells in vitro compared with the 25% obtained with phosphate-buffered saline solution (PBS). At 24 hours after treatment with OED, the number of microvilli and the mucin network were restored, as observed using scanning electron microscopy. In Vero E6 cells infected with a primary SARS-CoV-2 strain and treated with OED two times/day, viral replication was found to be inhibited, with a 70-fold reduction observed at 72 hours after infection compared with that under the untreated and PBS-treated conditions.

Conclusions

SARS-CoV-2 transmission through the ocular surface should not be ignored. Although the prevalence of coronavirus disease 2019 conjunctivitis infection is low, the need for a barrier to prevent possible viral infection is warranted. OED treatment may prevent the risk of SARS-CoV-2 infection after 72 hours of twice-daily applications.

Translational Relevance

Dry eye condition might be a risk factor for SARS-CoV-2 infection and OED treatment may have a preventive role.

Inhibitory Effect of Ophthalmic Solutions against SARS-CoV-2: A Preventive Action to Block the Viral Transmission?

In 2020, a global pandemic was declared following the spread of SARS-CoV-2, the pathogen responsible for COVID-19. The risk of infection is high due to the ease of transmission, which can occur orally, through droplets, or via contact with contaminated surfaces and objects. It has also been demonstrated that the ocular surface can constitute a transmission route, especially in hospital settings, where health care workers can become a dangerous source of infection. In order to increase prevention and reduce the spread of the virus on the ocular surface, the antiviral activity of already-marketed eye drops against SARS-CoV-2 was evaluated. Iodim, Ozodrop, Septavis, and Dropsept were tested against SARS-CoV-2 in plaque-assay experiments at different stimulation times. Furthermore, the expression levels of early and late genes were evaluated through molecular assays. Results indicated that three of the four ophthalmic solutions showed a considerable dose-dependent inhibition of viral replication, highlighting their use as potential antiviral drugs against SARS-CoV-2 and preventing other ocular infections.

Ozone-Based Eye Drops Activity on Ocular Epithelial Cells and Potential Pathogens Infecting the Front of the Eye

Confirmation of the biological effectiveness of new ophthalmic preparations introduced in the market is an important element in maintaining the safety of using this type of medications. This study aimed to investigate the activity of Ozodrop^® on human corneal and conjunctival epithelial cells, as well as its antibacterial and antifungal activity. Cytotoxicity analyses of ocular surface epithelial cells were performed in vitro by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) and Neutral Red uptake assays. The level of nitric oxide released by the cells was assessed by the Griess method. The reduction of the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical by the tested formulation was analyzed. Microbiological tests were also performed. It was found that the Ozodrop^® preparation exhibited biological activity, but was less active than the reference antibiotics and the anti-yeast agent. The cytotoxic activity of the Ozodrop^® formulation was dependent on the time of cell exposure to it. No toxic effect was observed in the short-term, for up to 3 h. It appeared after 24 h of exposure of the cells to the preparation. The drops showed antioxidant activity in the specified concentration range. They also stimulated the release of nitric oxide, mainly by corneal epithelial cells. The Ozodrop^® formulation exhibits biological activity that can be considered useful in the treatment of infections in the front part of the eye.

Topical Liposomal Ozonated Oil in Complicated Corneal Disease: A Report on Three Clinical Cases

Infectious and traumatic corneal diseases require adequate therapy against infection and promote re-epithelialization. The appearance of multidrug-resistant bacterial strains, induced by excessive use of antibiotics in the treatment of infectious diseases, has urged researchers to study new antimicrobial formulations. Ozonated oils have demonstrated antiseptic (antibacterial, antifungal and antiviral) and reparative properties and can be proposed for the prevention and treatment of acute and chronic local infections, as an alternative to conventional topical antimicrobials. In ocular treatment, ozonated oil can exert tissue repair and anti-inflammatory and bactericidal activity. Moreover, its specific formulation makes it well tolerated and biocompatible with the ocular surface. Herein, we report on three cases of corneal inflammation (dendritic epithelial keratitis, corneal injuries caused by olive leaves, and neurotrophic corneal ulcer), treated with liposomal ozonated oil (Ozodrop^®, FB VISION S.p.a. San Benedetto del Tronto, Italy), successfully resolved using topical liposomal ozonated oil.

The main uses of ozone therapy in diseases of large animals: A review

Ozone (O₃) is a molecule composed of three oxygen atoms, highly unstable, capable of reacting with various substances of the human and animal organism, giving rise to by-products that will participate in biochemical reactions. Thus, O₃ has a wide mechanism of action and can be used in different diseases of large animals. In those animals, the therapy is used mainly in reproductive diseases and wound healing.

The role of ozonized oil and a combination of tobramycin/dexamethasone eye drops in the treatment of viral conjunctivitis: a randomized clinical trial

Purpose

To determine whether topical tobramycin 0.3%/dexamethasone 0.1% plus ozonized oil eye drops reduces clinical signs and infectious viral titers of presumed viral conjunctivitis more than tobramycin/dexamethasone eye drops alone.

Methods

Prospective, single-blind, randomized, parallel-groups trial. Eighty patients with a clinical diagnosis of presumed viral conjunctivitis were randomizedly divided into two treatment groups: a study group and a control group, 40 for each group. Patients in the study group received topical tobramycin 0.3%/dexamethasone 0.1% eye drops, plus ozonized oil eye drops, both four times daily; patients in the control group received only topical tobramycin 0.3%/dexamethasone eye drops four times daily. The treatment was for seven days in both groups. Swabs were taken from the conjunctival fornix for adenovirus PCR analysis on the day of recruitment and at seven days follow-up. Clinical signs were also recorded on the day of recruitment and at follow-up examination: the main outcomes were conjunctival injection and conjunctival chemosis, graded on a 4-point clinical scale, presence or absence of superficial punctate keratitis and subepithelial corneal infiltrates.

Results

No statistically significant difference was reached in adenoviral infection negativization between the two groups, although the study group showed a higher number of PCR negative results at seven days follow-up. PCR real time detected adenoviral infection in 17 of 24 patients on the day of recruitment and it was positive in 4 patients on the seventh day (viral positivity reduction of 76%). In the control group PCR was positive for adenovirus in 18 of 24 patients on the day of recruitment and in 7 patients at seven days follow-up (reduction of 61%). There was statistically significant difference on conjunctival clinical signs between the study and control groups. Significant difference was also found on superficial punctate keratitis resolution between the study and the control group. In the former superficial punctate keratitis was detected in 14 eyes on the first day and in 5 eyes after seven days while in the latter superficial punctate keratitis was found in 124 eyes on the first day and in 6 eyes on the seventh day. No difference was found in subepithelial corneal infiltrates appearance between the two groups.

Conclusions

The use of ozonized-oil containing eye drops in combination with topical tobramycin 0.3%/dexamethasone 0.1% eye drops four times daily seems to reduce the signs of conjunctivitis, and the duration of viral infection, although it does not affect the subepithelial corneal infiltrates appearance.

Antimycotic Activity of Ozonized Oil in Liposome Eye Drops against Candida spp

Purpose

This study aims to investigate the antifungal activity and mechanism of action of ozonized oil eye drops in liposomes (Ozodrop), commercialized as eye lubricant for the treatment of dry eye syndrome and eye inflammation. The activity was tested against four clinical Candida species: C albicans, C glabrata, C krusei, and C orthopsilosis.

Methods

The antifungal activity of the eye drop solution was ascertained by microdilution method in accordance with EUCAST obtaining the minimum inhibitory concentration for Ozodrop. The mechanism of action was further investigated in C albicans by measuring cell vitality, intracellular reactive oxygen species production, levels of cellular and mitochondrial (∆Ψ_m) membrane potential, and the extent of membrane lipid peroxidation.

Results

All Candida isolates were susceptible to Ozodrop with minimum inhibitory concentration values ranging from 0.195% (v/v) for C glabrata to 6.25% (v/v) for C orthopsilosis. After 1 hour of exposure at the minimum inhibitory concentration value about 30% of cells were killed, reaching about 70% at the highest Ozodrop value. After Ozodrop exposure, C albicans showed cell membrane depolarization, increased levels of lipid peroxidation, depolarized ∆Ψ_m, and increased reactive oxygen species generation.

Conclusions

The significant increases in reactive oxygen species production cause the accumulation of reactive oxygen species-associated damages leading to progressive Candida cell dysfunction.

Translational Relevance

The antifungal activity of Ozodrop was demonstrated at concentrations several times lower than the concentration that can be retrieved in ocular surface after its application. The antifungal activity of the eye drops Ozodrop would represent an interesting off-label indication for a product basically conceived as an eye lubricant.

Ozone therapy in veterinary medicine: A review

Ozone (O₃) is a triatomic form of oxygen. As O₃ rapidly dissociates into water and releases a reactive form of oxygen that may oxidize cells, the gas mixture of O₃/O₂ is used in medicine. ATP is widely available for cellular activity. O₃ can be administered via the systemic and local routes. Although O₃ is known as one of the most powerful oxidants, it also promotes antioxidant enzymes. Additionally, it stimulates some of the cells of the immune system and inactivates pathogens, including bacteria, fungi, yeasts, protozoa, and viruses. Owing to these activities, O₃ is used to improve several diseases, both in human and in veterinary medicine. Considering the wide scope of O₃ application, the aim of this review was to reiterate the mechanisms of action of O₃ and its utilization in different mammalian species (bovine, ovine-caprine, equine, canine, porcine).

Advances and challenges in nanocarriers and nanomedicines for veterinary application

To ensure success in the development and manufacturing of nanomedicines requires forces of an interdisciplinary team that combines medicine, engineering, chemistry, biology, material and pharmaceutical areas. Numerous researches in nanotechnology applied to human health are available in the literature. Althought, the lack of nanotechnology-based pharmaceuticals products for use exclusively in veterinary pharmacotherapy creates a potential area for the development of innovative products, as these animal health studies are still scarce when compared to studies in human pharmacotherapy. Nano-dosage forms can ensure safer and more effective pharmacotherapy for animals and can more be safer for the consumers of livestock products, once they can offer higher selectivity and smaller toxicity associated with lower doses of the drugs. In addition, the development and production of nanomedicines may consolidate the presence of pharmaceutical laboratories in the global market and can generate greater profit in a competitive business environment. To contribute to this scenario, this article provides a review of the main nanocarriers used in nanomedicines for veterinary use, with emphasis on liposomes, nanoemulsions, micelles, lipid nanoparticles, polymeric nanoparticles, mesoporous silica nanoparticles, metallic nanoparticles and dendrimers, and the state of the art of application of these nanocarriers in drug delivery systems to animal use. Finnaly, the major challenges involved in research, scale-up studies, large-scale manufacture, analytical methods for quality assessment, and regulatory aspects of nanomedicines were discussed.

Ozonated Oils as Antimicrobial Systems in Topical Applications. Their Characterization, Current Applications, and Advances in Improved Delivery Techniques

The search for a wide spectrum of antimicrobial agents that can avoid resistance while maintaining reasonable side effects has led to ozonated oils experiencing an increase in scientific interest and clinical applications. The treatment of vegetable oils with ozone leads to the creation of a reservoir of ozone that slowly releases into the skin thanks to the fact that ozone can be held as ozonides of unsaturated fatty acids. Interest in the use of ozonated oils has meant that several ozonated-vegetable-oil-containing products have been commercialized as cosmetic and pharmaceutical agents, and in innovative textile products with antibacterial activity. New approaches to the delivery of ozonated oils have very recently appeared in an attempt to improve their characteristics and reduce drawbacks, such as an unpleasant odor, high viscosity and undesired effects on skin, including irritation and rashes. The present review focuses on the current status of delivery agents that use ozonated oils as antimicrobial agents in topical (dermal, skin, and soft tissues) treatments. Challenges and future opportunities for these delivery systems will also be discussed.

Pathogenetic role of Staphylococcus aureus in purulent keratoconjunctivitis in cats

The research was carried out in the Department of Surgery and Obstetrics of Agricultural Animals of Dnipro State Agrarian and Economic University on clinically healthy outbred cats of different ages with purulent keratoconjunctivitis. Hematological, biochemical and immunological parameters were determined in the animals, and microbiological and virological research was conducted on them. According to the data obtained, more than half of cases of ophthalmopathology in cats were conjunctivitis and keratoconjunctivitis, and they were more often registered in the cold season. The main causes of eye diseases in the cats were mechanical injuries, coccal and chlamydial infection, allergy and development of disease against the background of primary lesions of the ears and paranasal sinuses. Among the detected microorganisms, the vast majority (81.9%) were staphylococci, including S. albus, S. aureus and S. epidermidis. All types of microorganisms except O-forms of Bacillus sp. exhibited high and medium sensitivity to antibiotics. Immunoblotting revealed polypeptides that responded to specific S. aureus antigens in samples of conjunctiva, cornea, intraocular fluid, and blood of cats suffering from purulent (staphylococcal) keratoconjunctivitis. The highest antigen concentration was detected in the cornea and conjunctiva. In the absence of expressive shifts of the investigated hematological and biochemical parameters, the dynamics of immunological markers were shown by a significant increase in the content of immunoglobulins and circulating immune complexes, as well as by a distinct activation of the complement system by the classical route. The results showed a clear gradual activation of phagocytosis, namely: the number of phagocytic neutrophils increased, reaching its maximum value by the seventh day of development of purulent keratoconjunctivitis. The phagocytic index in the first three days of observation tended to decrease, and by the seventh day it had already significantly exceeded the initial value. Despite the ambiguous dynamics of the phagocytic index, in the course of the development of the inflammatory process in the blood of sick cats, we observed a clear increase in the index of complete phagocytosis. Thus, the development of purulent keratoconjunctivitis in cats occurs against the background of clear cellular and humoral responses to the infectious agent.

Preoperative topical liposomal ozone dispersion to reduce bacterial colonization in conjunctival sac and periocular skin: Preliminary study in dogs

Prophylaxis represents a keystone to reduce periocular skin and ocular conjunctiva bacterial load before surgical procedures. Despite many prophylactic agents are available the preferred perioperative ocular surface antimicrobial is still unknown. The purpose of this study was to assess the effectiveness of preoperative liposomal ozone dispersion in reducing bacterial colonization from the conjunctival sac and periocular skin in dogs, in comparison with povidone-iodine and fluoroquinolone. Twenty-two owned dogs consisting with 44 eyes in total scheduled for ophthalmic surgical procedure were enrolled for the study and divided in four groups receiving either ozone dispersion or povidone iodine in eyelid and conjunctiva, fluoroquinolone or placebo. A swab was taken before and after the antisepsis protocol evaluating total microbial count, coagulase positive and negative staphylococci. Statistical analysis revealed a significant decrease in colony forming units (CFU) for total microbial count, coagulase positive and negative staphylococci both for liposomal ozone dispersion and povidone iodine. No statistical differences were detected in median CFU for both one-day placebo and fluoroquinolone preoperative prophylactic topical therapy. The results of this preliminary study demonstrate that liposomal ozone-dispersion is as effective as povidone iodine to reduce preoperative bacterial load in ocular surface.