Mechanisms that lead to Eosinophilic Chronic Rhinosinusitis (ECRS) are not fully established in the literature. It is desirable to assess ECRS in a model that embraces most of the related events. This article reviewed the murine models for ECRS and compared them regarding eosinophilic polypoid formation. The authors reviewed the articles that included the terms “chronic rhinosinusitis” OR “chronic sinusitis” AND “animal model”. We analyzed articles in English that evaluated both the number of polyps and the number of eosinophils in the sinus mucosa of mouse models. We identified a total of 15 articles describing different models of ECRS that used BALB/c or C57BL/6 mice, and different triggers/stimulants such as Staphylococcus aureus Enterotoxin B (SEB) + Ovalbumin (OVA); House Dust Mite (HDM) ± Ovalbumin (OVA); and Aspergillus oryzae Protease (AP) + Ovalbumin (OVA). OVA associated with SEB was the commonest protocol to induce ECRS in both BALB/c and C57BL/6 mice, and it produced a robust response of eosinophilic nasal polyps in both. AP + OVA protocol also led to a good ECRS response. The other models were not considered adequate to produce eosinophilic polyps in mice. In conclusion, OVA associated with SEB seems to produce the most robust eosinophilic sinonasal inflammation.

Diabetes mellitus (DM) and hypothyroidism (HT) are prevalent diseases associated with dry eye (DE). Their impact on the lacrimal functional unit (LFU) is poorly known. This work evaluates the changes in the LFU in DM and HT. Adult male Wistar rats had the disease induced as follows: (a) DM: streptozotocin and (b) HT: methimazole. The tear film (TF) and blood osmolarity were measured. Cytokine mRNA was compared in the lacrimal gland (LG), trigeminal ganglion (TG), and cornea (CO). Oxidative enzymes were evaluated in the LG. The DM group showed lower tear secretion (p = 0.02) and higher blood osmolarity (p < 0.001). The DM group presented lower mRNA expression of TRPV1 in the cornea (p = 0.03), higher Il1b mRNA expression (p = 0.03), and higher catalase activity in the LG (p < 0.001). The DM group presented higher Il6 mRNA expression in the TG (p = 0.02). The HT group showed higher TF osmolarity (p < 0.001), lower expression of Mmp9 mRNA in the CO (p < 0.001), higher catalase activity in the LG (p = 0.002), and higher expression of Il1b mRNA in the TG (p = 0.004). The findings revealed that DM and HT induce distinct compromises to the LG and the entire LFU.

The burden of corneal blindness and visual deficiency can be felt worldwide. Its association with several endemic diseases such as childhood blindness, trauma, infectious keratitis (including variants caused by herpes, hanseniasis, and fungi), vitamin A deficiency, diabetes mellitus, and other dry eye syndromes reflects its poorly understood underlying mechanisms and suggests that the actual frequency of the disease is underestimated. The low effectiveness of preventive and therapeutic strategies against corneal scarring or deformity predicts a high frequency of patients with corneal blindness in the future. Corneal blindness is associated with environmental factors and socioeconomic limitations that restrain health assistance and maintain a modest efficiency of the current therapeutic strategies for resolving corneal diseases in large-scale programs. We present here a critical review of the concepts associated with corneal blindness that need to be considered when planning strategies to prevent and treat corneal blindness worldwide (to be able to leave Plato's cave, where corneal blindness is encaged.

The study evaluated the regenerative responses of the lacrimal functional unit (LFU) after lacrimal gland (LG) ablation. The LG of Wistar rats was submitted to G1) partial LG ablation, G2) partial ablation and transplantation of an allogeneic LG, or G3) total LG ablation, (n = 7–10/group). The eye wipe test, slit lamp image, tear flow, and histology were evaluated. RT-PCR analyzed inflammatory and proliferation mediators. The findings were compared to naïve controls after 1 and 2 months (M1 and M2). G3 presented increased corneal sensitivity, and the 3 groups showed corneal neovascularization. Histology revealed changes in the LG and corneal inflammation. In the LG, there was an increase in MMP-9 mRNA of G1 and G2 at M1 and M2, in RUNX-1 at M1 and M2 in G1, in RUNX-3 mRNA at M1 in G1, and at M2 in G2. TNF-α mRNA rose in the corneas of G1 and G2 at M2. There was an increase in the IL-1β mRNA in the trigeminal ganglion of G1 at M1. Without changes in tear flow or evidence of LG regeneration, LG ablation and grafting are unreliable models for dry eye or LG repair in rats. The surgical manipulation extended inflammation to the LFU.

Dry eye disease (DED) is a hallmark of primary Sjögren’s disease (SjD) and often resists conventional treatments like lubricant eye drops. Insulin nanoemulsions offer a potential solution by improving drug penetration and retention on the ocular surface. In animal models, insulin has shown benefits in promoting tear secretion and corneal healing. This study evaluated the safety and efficacy of insulin nanoemulsion eye drops (20 IU/mL, three times daily for 30 days) in patients with SjD. Thirty-two patients were randomized in a double-masked design to receive either insulin or placebo drops. Symptoms (assessed by OSDI questionnaire) and objective measures (tear film breakup time, corneal and conjunctival staining, and Schirmer Test) were recorded at baseline, after 4 weeks of treatment, and at a 4-week follow-up. Twenty-three participants completed the study. Both groups showed significant improvement in symptoms and objective signs after treatment (p < 0.05), but no significant differences were found between the insulin and placebo groups. No clinically relevant adverse effects were reported. Insulin nanoemulsion eye drops are safe for SjD patients, but their therapeutic advantage remains unclear. Further studies with larger samples, extended follow-up, and dose adjustments are needed to better understand their potential.

Ocular surface (OS) and dry eye (DE) symptoms are frequent ophthalmic complaints influenced by climate and pollution related with acute and chronic ocular surface symptoms. This study assessed their association with environmental conditions in São Paulo metropolitan area (2016–2020), including air temperature, humidity, atmospheric pressure, ozone (O₃), particulate matter (PM), using IQVIA eye drop sales data and Google search trends. Sympathomimetic decongestant sales correlated with higher temperature (r = 0.434, p = 0.0021), UV radiation (r = 0.643, p < 0.0001), and ozone (r = 0.491, p = 0.0004). Artificial tears and lubricants correlated with ozone (r = 0.452, p = 0.0012) and with searches for “red eye” (r = 0.505, p = 0.0005) and “stye” (r = 0.599, p < 0.0001). To address multicollinearity, Principal Component Analysis (PCA) was applied, with the first two components (PC1 and PC2) explaining 87.3% of variance. Regression models using these components were significant for decongestant sales and “stye” searches. Eye drop sales and search trends thus emerge as potential indicators of OS and DE symptoms, reflecting environmental conditions and informing prevention strategies.