Retinol binding protein status in relation to ocular surface changes in patients with cystic fibrosis treated with daily vitamin A supplements

The role of CFTR in the eye, and the effect of early highly effective modulator treatment for cystic fibrosis on eye health

Cystic fibrosis transmembrane conductance regulator (CFTR) is a protein that plays a crucial role in various human organs, including the respiratory and digestive systems. Dysfunctional CFTR is the key variant of the lethal genetic disorder, cystic fibrosis (CF). In the past decade, highly effective CFTR modulator therapies, including elexacaftor-tezacaftor-ivacaftor, have revolutionised CF management by correcting the underlying molecular defect to improve patient outcomes and life expectancy. Despite demonstrating multiorgan efficacy, clinical studies have largely overlooked the potential for ocular disturbances with CFTR modulator therapy, with the exception of a few case studies reporting the presence of crystalline lens pathologies in young children on CFTR modulators, and in breastfed infants born to individuals who were on CFTR modulator treatment during pregnancy. CFTR is present in multiple tissues during embryonic development, including the eye, and its expression can be influenced by genetic and environmental factors. This review summarises the role of CFTR in the eye, and the potential impact of CFTR on eye function and vision later in life. This information provides a framework for understanding the use and possible effects of CFTR-modulating therapeutics in the context of eye health, including the potential to leverage the eye for non-invasive and accessible diagnostic and monitoring capabilities in patients with CF.

Advantages and Disadvantages of Using Magnetic Nanoparticles for the Treatment of Complicated Ocular Disorders

Nanomaterials provide enormous opportunities to overcome the limitations of conventional ocular delivery systems, such as low therapeutic efficacy, side effects due to the systemic exposure, or invasive surgery. Apart from the more common ocular disorders, there are some genetic diseases, such as cystic fibrosis, that develop ocular disorders as secondary effects as long as the disease progresses. These patients are more difficult to be pharmacologically treated using conventional drug routes (topically, systemic), since specific pharmacological formulations can be incompatible, display increased toxicity, or their therapeutic efficacy decreases with the administration of different kind of chemical molecules. Magnetic nanoparticles can be used as potent drug carriers and magnetic hyperthermia agents due to their response to an external magnetic field. Drugs can be concentrated in the target point, limiting the damage to other tissues. The other advantage of these magnetic nanoparticles is that they can act as magnetic resonance imaging agents, allowing the detection of the exact location of the disease. However, there are some drawbacks related to their use in drug delivery, such as the limitation to maintain efficacy in the target organ once the magnetic field is removed from outside. Another disadvantage is the difficulty in maintaining the therapeutic action in three dimensions inside the human body. This review summarizes all the application possibilities related to magnetic nanoparticles in ocular diseases.

Inflammatory manifestations in patients with Shwachman-Diamond syndrome: A novel phenotype

Shwachman-Diamond syndrome (SDS) is an autosomal recessive multisystem disorder characterized by exocrine pancreatic dysfunction, bone marrow failure, and leukemia predisposition. Approximately 90% of cases are due to biallelic mutations in the Shwachman-Bodian-Diamond (SBDS) gene. Additional phenotypic features variably associated with SDS include skeletal, neurologic, hepatic, cardiac, endocrine, and dental abnormalities. We report five subjects with SDS who developed a range of inflammatory manifestations. Three patients developed inflammatory eye conditions. Single cases of juvenile idiopathic arthritis, chronic recurrent multifocal osteomyelitis, and scleroderma were also noted. Clinical presentation and treatment responses are described. Proteomic analysis revealed increased inflammatory signatures in SDS subjects as compared to controls. Treatment of inflammatory manifestations in patients with SDS may be complicated by potential myelosuppressive toxicities of anti-rheumatic medications. Further research is needed to better understand the potential link between inflammatory disorders and SDS to inform effective treatment strategies.

Evaluation of plasma vitamin A and E levels and tear film changes in patients with psoriasis vulgaris

Purpose

To evaluate whether alterations in plasma vitamin A and E levels in patients with psoriasis have an effect on tear film changes.

Methods

Sixty-two eyes of 31 patients with psoriasis vulgaris (Group A) and 74 eyes of 37 age- and gender-matched control subjects (Group B) were included in the study. Ocular and medical histories and dietary habits were obtained from each patient. The tear film break-up time (TBUT), the Schirmer 1 test results and plasma vitamin A and E levels were evaluated.

Results

The mean Schirmer 1 test score was 14.76 ± 6.12 mm/5 min in Group A and 15.69 ± 3.10 mm/5 min in Group B. The mean plasma levels of vitamins A and E in Groups A and B were 1.86 ± 0.62 µmol/L and 1.88 ± 0.65 µmol/L vs. 26.21 ± 5.13 µmol/L and 27.19 ± 8.89 µmol/L, respectively. The Schirmer 1 test results and plasma vitamin A and E levels were not found to be significantly different between the groups (p > 0.05). The mean TBUT was 9.94 ± 6.18 seconds in Group A and 14.47 ± 5.65 seconds in Group B, a significant difference (p < 0.05). No correlation existed between plasma vitamin A and E levels, TBUT or the severity and duration of the disease (p > 0.05).

Conclusions

Plasma vitamin A and E levels do not seem to be related to tear film changes in patients with psoriasis vulgaris.

Increased expression of cellular retinol-binding protein 1 in laryngeal squamous cell carcinoma

PURPOSE

To investigate the genomic alterations in larynx carcinomas (LaCa) tissues and its prognostics values in predicting survival.

METHODS

To analyse the aberrations in the genome of LaCa patients, we used array comparative genomic hybridization in 19 human laryngeal tumour samples. DNA samples were also subjected to detect human papillomavirus (HPV) sequences by polymerase chain reaction (PCR). Copy number gain was confirmed by real-time PCR. The cellular retinol-binding protein 1 (CRBP-1) gene expression was also confirmed by immunohistochemistry assay on LaCa tissues. To identify prognostic feature, CRBP-1 gene gain was correlated to patient survival.

RESULTS

The most common gains were detected for CRBP-1 and EGFR genes, while DNA lost in RAF-1 gene. Immunohistochemistry assay was revealed strong expression of CRBP1 protein in those cases with CRBP-1 gene gain. The CRBP-1 gene gain and its expression correlated significantly with survival (P = 0.003). Cox regression analysis indicated that CRBP-1 expression level was a factor of survival (P = 0.008). HPV sequences were detected in 42% of the samples, and did not show any relationship with specific gene alterations.

CONCLUSION

Our data shows that CRBP-1 gene gain can be determined by immunohistochemistry on routinely processed tissue specimens, and could support as a potential novel marker for long-term survival in laryngeal squamous cell carcinoma.

Dependence of cAMP meditated increases in Cl- and HCO(3)- permeability on CFTR in bovine corneal endothelial cells

The cystic fibrosis transmembrane conductance regulator (CFTR) is present on the apical membrane of corneal endothelial cells. Increasing intracellular [cAMP] with forskolin stimulates an NPPB and glibenclamide-inhibitable apical Cl(-) and HCO(3)(-) permeability [Sun, X.C., Bonanno, J.A., 2002. Expression, localization, and functional evaluation of CFTR in bovine corneal endothelial cells. Am. J. Physiol. Cell Physiol. 282, C673-C683]. To definitively determine that the increased permeability is dependent on CFTR, we used an siRNA knockdown approach. Apical Cl(-) and HCO(3)(-) permeability and steady-state HCO(3)(-) flux were measured in the presence or absence of forskolin using cultured bovine corneal endothelial cells that were transfected with CFTR siRNA or a scrambled sequence control. CFTR protein expression was reduced by approximately 80% in CFTR siRNA treated cultures. Forskolin (10 microM) increased apical chloride permeability by 7-fold, which was reduced to control level in siRNA treated cells. CFTR siRNA treatment had no effect on baseline apical chloride permeability. Apical HCO(3)(-) permeability was increased 2-fold by 10 microM forskolin, which was reduced to control level in siRNA treated cultures. Similarly, there was no effect on baseline apical HCO(3)(-) permeability by knocking down CFTR expression. The steady-state apical-basolateral pH gradient (DeltapH) at 4h in control cultures was increased approximately 2.5-fold by forskolin. In CFTR siRNA treated cells, the baseline DeltapH was similar to control, however forskolin did not have a significant effect. We conclude that forskolin induced increases in apical HCO(3)(-) permeability in bovine corneal endothelium requires CFTR. However, CFTR does not have a major role in determining baseline apical chloride or HCO(3)(-) permeability.