Topical Insulin in Neurotrophic Keratopathy: A Review of Current Understanding of the Mechanism of Action and Therapeutic Approach

Combined use of pritelivir with acyclovir or foscarnet suppresses evolution of HSV-1 drug resistance

The widespread use of antivirals in immunocompromised individuals has led to frequent occurrences of drug-resistant herpes simplex virus 1 (HSV-1) infections. Current antivirals target the viral DNA polymerase (DP), resulting in cross-resistance patterns that emphasize the need for novel treatment strategies. In this study, we assessed whether combining antivirals with different targets affects drug resistance emergence by passaging wild-type HSV-1 under increasing concentrations of acyclovir (ACV), foscarnet (phosphonoformic acid, PFA), or the helicase-primase inhibitor pritelivir (PTV), individually or in combination (ACV + PTV or PFA + PTV). The resistance selection procedure was initiated from two different drug concentrations for each condition. Deep sequencing and subsequent phenotyping showed the rapid acquisition of resistance mutations under monotherapy pressure, whereas combination therapy resulted in either no mutations or mutations conferring ACV and/or PFA resistance. Notably, mutations associated with PTV resistance were not detected after five passages under combination pressure. Strains resistant to both ACV and PTV were eventually obtained upon further passaging under ACV + PTV pressure initiated from lower drug concentrations. PFA + PTV dual treatment induced PFA resistance mutations in the DP, but PTV resistance mutations were not acquired, even after 15 passages. Our data suggest that combining the helicase-primase inhibitor PTV with a DP inhibitor may be an effective strategy to prevent drug resistance evolution in HSV-1.

Double-Arc Slow-Coagulation Transscleral Cyclophotocoagulation Laser Protocol: One-Year Effectiveness and Safety Outcomes

PURPOSE

To report the short-term effectiveness and safety results of a new continuous laser protocol, double-arc slow-coagulation transscleral cyclophotocoagulation (DA-TSCPC).

DESIGN

Multicenter retrospective study.

PARTICIPANTS

We reviewed the clinical records of refractory glaucoma patients that had undergone DA-TSCPC between April 2019 and July 2022, with at least 12 months of postoperative follow-up.

METHODS

The technique was standardized (energy: 1400 mW; duration: 4 seconds; 28 applications). The applications were divided into 2 rows (upper and lower arcs). For each arc, 7 spots were applied over the ciliary body shadow and 7 spots 1.5 mm behind, sparing the 3 and 9 o'clock meridians.

MAIN OUTCOME MEASURES

Success was defined as postoperative intraocular pressure (IOP) between 6 and 18 mmHg and an IOP reduction of 30% (without oral acetazolamide). For eyes with no light perception (NLP), in which treatment goal was pain relief, success was defined as a 30% IOP reduction and no pain (without oral acetazolamide). Patients were divided according to visual acuity: ≥ 20/400 (group 1) and < 20/400 (group 2).

RESULTS

Ninety eyes of 90 patients (mean age: 61 ± 15 years) were included. Glaucoma diagnosis frequency was: neovascular glaucoma (38%), open-angle glaucoma (28%), silicone oil secondary glaucoma (17%), and others (18%). Overall, the mean IOP was significantly reduced from 35 ± 12 to 22 ± 14 mmHg (P < 0.01) at the last follow-up visit. The number of hypotensive eye drops (2.6 ± 1-2.3 ± 1; P = 0.02) and the use of oral acetazolamide (61%-11%; P < 0.01) were also reduced. Kaplan-Meier survival analysis revealed a global success rate of 65.6% after 12 months. A higher success rate was found for group 1 (78.6%) compared to group 2 (59.6%; P = 0.047; logrank test). The main complications observed were corneal ulcer (4.4%), macular edema (1.1%), and hyphema (1.1%). Among the 26 eyes with NLP, 65% achieved success criteria at 12 months and 2 (7.7%) developed phthisis.

CONCLUSIONS

Based on these initial retrospective data, the DA-TSCPC protocol seems to be an alternative for refractory glaucoma management, presenting significant IOP reduction and a good safety profile after 1 year. Better outcomes were observed in eyes with less severe functional damage.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Transforming Cancer Treatment with Nanotechnology: The Role of Berberine as a Star Natural Compound

Berberine (BBR), recognized as an oncotherapeutic phytochemical, exhibits its anti-cancer properties via multiple molecular pathways. However, its clinical application is hindered by suboptimal tumor accumulation, rapid systemic elimination, and diminished bioactive concentration owing to extensive metabolic degradation. To circumvent these limitations, the strategic employment of nanocarriers and other drugs in combination with BBR is emerging as a focus to potentiate its anti-cancer efficacy. This review introduced the expansive spectrum of BBR's anti-cancer activities, BBR and other drugs co-loaded nanocarriers for anti-cancer treatments, and evaluated the synergistic augmentation of these amalgamated modalities. The aim is to provide an overview of BBR for cancer treatment based on nano-delivery. Berberine (BBR), recognized as an oncotherapeutic phytochemical, exhibits its anti-cancer properties via multiple molecular pathways. However, its clinical application is hindered by suboptimal tumor accumulation, rapid systemic elimination, and diminished bioactive concentration owing to extensive metabolic degradation. To circumvent these limitations, the strategic employment of nanocarriers and other drugs in combination with BBR is emerging as a focus to potentiate its anti-cancer efficacy. Nano-delivery systems increase drug concentration at the tumor site by improving pharmacological activity and tissue distribution, enhancing drug bioavailability. Organic nanocarriers have advantages for berberine delivery including biocompatibility, encapsulation, and controlled release of the drug. While the advantages of inorganic nanocarriers for berberine delivery mainly lie in their efficient loading ability of the drug and their slow release ability of the drug. This review introduced the expansive spectrum of BBR's anti-cancer activities, BBR and other drugs co-loaded nanocarriers for anti-cancer treatments, and evaluated the synergistic augmentation of these amalgamated modalities. The aim is to provide an overview of BBR for cancer treatment based on nano-delivery.

The Utilization of Topical Insulin for Ocular Surface Diseases: A Narrative Review

Various etiologies, including diabetic keratopathy (DK), dry eye disease (DED), and neurotrophic keratopathy (NK), can disrupt corneal homeostasis, exacerbating corneal epithelial defects. Topical insulin has emerged as a promising therapy for promoting corneal wound healing and addressing underlying pathologies. This review systematically evaluates the efficacy of topical insulin across different corneal disorders. A literature review was conducted across the PubMed, Google Scholar, and Scopus research databases. The search resulted in a total of 19 articles, consisting of clinical trials, retrospective studies, and case reports. In DK, topical insulin accelerates corneal wound healing post-vitreoretinal surgery with lower concentrations showing higher outcomes when compared to conventional therapy, possibly due to improved epithelial stem cell migration. In comparison, the dry-eye disease results are inconclusive regarding patient-reported outcomes and corneal staining. For NK, topical insulin accelerates corneal wound healing and restores corneal nerve sensation. Other persistent epithelial defect (PED) etiologies that have been treated with topical insulin are infection, immune-mediated, mechanical and chemical trauma, and chronic ocular surface alterations. Although individual mechanisms for the benefits of topical insulin for each of these etiologies have not been studied, the literature demonstrates that topical insulin is efficacious for PEDs regardless of etiology. Future clinical trials need to be conducted to further evaluate optimal dosing, duration, and use of topical insulin for the restoration of the corneal surface.

Recent United States Developments in the Pharmacological Treatment of Dry Eye Disease

Dry eye disease (DED) can arise from a variety of factors, including inflammation, meibomian gland dysfunction (MGD), and neurosensory abnormalities. Individuals with DED may exhibit a range of clinical signs, including tear instability, reduced tear production, and epithelial disruption, that are driven by different pathophysiological contributors. Those affected often report a spectrum of pain and visual symptoms that can impact physical and mental aspects of health, placing an overall burden on an individual's well-being. This cumulative impact of DED on an individual's activities and on society underscores the importance of finding diverse and effective management strategies. Such management strategies necessitate an understanding of the underlying pathophysiological mechanisms that contribute to DED in the individual patient. Presently, the majority of approved therapies for DED address T cell-mediated inflammation, with their tolerability and effectiveness varying across different studies. However, there is an emergence of treatments that target additional aspects of the disease, including novel inflammatory pathways, abnormalities of the eyelid margin, and neuronal function. These developments may allow for a more nuanced and precise management strategy for DED. This review highlights the recent pharmacological advancements in DED therapy in the United States. It discusses the mechanisms of action of these new treatments, presents key findings from clinical trials, discusses their current stage of development, and explores their potential applicability to different sub-types of DED. By providing a comprehensive overview of products in development, this review aims to contribute valuable insights to the ongoing efforts in enhancing the therapeutic options available to individuals suffering from DED.

The Role of Insulin-like Growth Factor (IGF) System in the Corneal Epithelium Homeostasis-From Limbal Epithelial Stem Cells to Therapeutic Applications

The corneal epithelium, comprising three layers of cells, represents the outermost portion of the eye and functions as a vital protective barrier while concurrently serving as a critical refractive structure. Maintaining its homeostasis involves a complex regenerative process facilitated by the functions of the lacrimal gland, tear film, and corneal nerves. Crucially, limbal epithelial stem cells located in the limbus (transitional zone between the cornea and the conjunctiva) are instrumental for the corneal epithelium integrity by replenishing and renewing cells. Re-epithelialization failure results in persistent defects, often associated with various ocular conditions including diabetic keratopathy. The insulin-like growth factor (IGF) system is a sophisticated network of insulin and other proteins essential for numerous physiological processes. This review examines its role in maintaining the corneal epithelium homeostasis, with a special focus on the interplay with corneal limbal stem cells and the potential therapeutic applications of the system components.

Diabetic Keratopathy: Redox Signaling Pathways and Therapeutic Prospects

Diabetes mellitus, the most prevalent endocrine disorder, not only impacts the retina but also significantly involves the ocular surface. Diabetes contributes to the development of dry eye disease and induces morphological and functional corneal alterations, particularly affecting nerves and epithelial cells. These changes manifest as epithelial defects, reduced sensitivity, and delayed wound healing, collectively encapsulated in the context of diabetic keratopathy. In advanced stages of this condition, the progression to corneal ulcers and scarring further unfolds, eventually leading to corneal opacities. This critical complication hampers vision and carries the potential for irreversible visual loss. The primary objective of this review article is to offer a comprehensive overview of the pathomechanisms underlying diabetic keratopathy. Emphasis is placed on exploring the redox molecular pathways responsible for the aberrant structural changes observed in the cornea and tear film during diabetes. Additionally, we provide insights into the latest experimental findings concerning potential treatments targeting oxidative stress. This endeavor aims to enhance our understanding of the intricate interplay between diabetes and ocular complications, offering valuable perspectives for future therapeutic interventions.

Biosynthesis of Copper Oxide-Silver Nanoparticles from Ephedra Intermedia Extract and Study of Anticancer Effects in HepG2 Cell Line: Apoptosis-Related Genes Analysis and Nitric Oxide Level Investigations

Liver cancer treatment faces significant obstacles such as resistance, recurrence, metastasis, and toxicity to healthy cells. Biometallic nanoparticles (NPs) have emerged as a promising approach to address these challenges. In this study, copper oxide-silver (Ag-doped CuO) NPs were prepared using a reduction method with Ephedra intermedia extract. The physicochemical properties of the NPs were evaluated using various techniques such as Field emission scanning electron microscopy (FESEM), Transmission Electron Microscope (TEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). Additionally, this study has evaluated nitric oxide levels (NO), reactive oxygen species (ROS) production, Bax, Bcl2, P53, and Caspase3 genes expression, as well as cell viability within 24 hours in liver cancer cell line HepG2. FESEM and TEM imaging confirmed the nanostructural nature of the synthesized particles with sizes ranging from 31.27 to 88.98 nanometers. XRD analysis confirmed the crystal structure of the NPs. Comparative analysis showed that the IC50 values of the Ag-doped CuO NPs were significantly lower than that of the plant extracts. Molecular studies showed significantly increased expression of Bax, Caspase3, and P53 genes, inducing apoptosis in cancer cells, and downregulation of Bcl2 as a pro-metastasis gene. Additionally, the presence of Ag-doped CuO NPs significantly increased NO activity enzyme and ROS generation compared to the plant extract. The biosynthesized Ag-doped CuO NPs demonstrated the ability to induce apoptosis, increase ROS production, and enhance NO enzyme activity in HepG2 cancer cells, suggesting their potential as a therapeutic agent for liver cancer.