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Purpose: The management of blepharitis continues to challenge clinicians due to the poorly understood aetiology of the condition. We recently identified the family of intracellular plakin proteins as essential driving forces underlying anterior blepharitis. A large‐scale protein analysis was used to study if a topical dexamethasone/tobramycin solution could be used to reverse the expression of plakin proteins. Methods: Tear film samples from treatment naïve patients with anterior blepharitis (n = 15) were collected with Schirmer filtration paper. A subgroup of the patients (n = 10) received treatment with a dexamethasone/tobramycin 1 + 3 mg/mL ophthalmic suspension (Tobradex®) for 3 weeks and collection of tear film samples was repeated. The samples were analysed with label‐free quantification nano liquid chromatography–tandem mass spectrometry requiring quantification in at least 70% of the samples in each group. Proteins were considered differentially expressed if p < 0.05. Results: Following Tobradex® intervention, 27 proteins were upregulated while 61 proteins were downregulated. Regulated proteins after Tobradex® treatment were involved in intermediate filament cytoskeleton organization including downregulation of the plakin proteins envoplakin, epiplakin and periplakin. Plectin, a protein of the plakin family, remained unchanged after Tobradex® therapy. Tobradex® treatment resulted in the regulation of proteins involved in translation including a cluster of downregulated ribosomal proteins. Tobradex® intervention was associated with the regulation of proteins involved in fructose metabolism and glycolytic processes including fructose‐1.6‐bisphosphatase 1, fructose‐bisphosphate aldolases A and B, pyruvate kinase PKM and transketolase. Ig lambda chain V‐I region, prominin‐1, and protein Niban were upregulated after Tobradex® treatment. Conclusions: Tobradex treatment reversed the expression of plakin proteins in anterior blepharitis. Topical solutions which inhibit the expression of plakin proteins may have the potential to restore the ocular surface integrity in anterior blepharitis and should be explored further. [ABSTRACT FROM AUTHOR]

Insulin-like growth factor-1 (IGF-1) is a pleiotropic molecule with neurotrophic and immunomodulatory functions. Knowing the capacity of chronically activated microglia to produce IGF-1 may therefore show essential to promote beneficial microglial functions in Alzheimer's disease (AD). Here, we investigated the expression of IGF-1 mRNA and IGF-1 along with the expression of tumor necrosis factor (TNF) mRNA, and the amyloid-β (Aβ) plaque load in the hippocampus of 3- to 24-month-old APPswe/PS1ΔE9 transgenic (Tg) and wild-type (WT) mice. As IGF-1, in particular, is implicated in neurogenesis we also monitored the proliferation of cells in the subgranular zone (sgz) of the dentate gyrus. We found that the Aβ plaque load reached its maximum in aged 21- and 24-month-old APPswe/PS1ΔE9 Tg mice, and that microglial reactivity and hippocampal IGF-1 and TNF mRNA levels were significantly elevated in aged APPswe/PS1ΔE9 Tg mice. The sgz cell proliferation decreased with age, regardless of genotype and increased IGF-1/TNF mRNA levels. Interestingly, IGF-1 mRNA was expressed in subsets of sgz cells, likely neuroblasts, and neurons in both genotypes, regardless of age, as well as in glial-like cells. By double in situ hybridization these were shown to be IGF1 mRNA+ CD11b mRNA+ cells, i.e., IGF-1 mRNA-expressing microglia. Quantification showed a 2-fold increase in the number of microglia and IGF-1 mRNA-expressing microglia in the molecular layer of the dentate gyrus in aged APPswe/PS1ΔE9 Tg mice. Double-immunofluorescence showed that IGF-1 was expressed in a subset of Aβ plaque-associated CD11b+ microglia and in several subsets of neurons. Exposure of primary murine microglia and BV2 cells to Aβ42 did not affect IGF-1 mRNA expression. IGF-1 mRNA levels remained constant in WT mice with aging, unlike TNF mRNA levels which increased with aging. In conclusion, our results suggest that the increased IGF-1 mRNA levels can be ascribed to a larger number of IGF-1 mRNA-expressing microglia in the aged APPswe/PS1ΔE9 Tg mice. The finding that subsets of microglia retain the capacity to express IGF-1 mRNA and IGF-1 in the aged APPswe/PS1ΔE9 Tg mice is encouraging, considering the beneficial therapeutic potential of modulating microglial production of IGF-1 in AD. [ABSTRACT FROM AUTHOR]

Purpose: The management of blepharitis continues to challenge clinicians due to the poorly understood aetiology of the condition. We recently identified the family of intracellular plakin proteins as essential driving forces underlying anterior blepharitis. A large-scale protein analysis was used to study if a topical dexamethasone/tobramycin solution could be used to reverse the expression of plakin proteins., Methods: Tear film samples from treatment naïve patients with anterior blepharitis (n = 15) were collected with Schirmer filtration paper. A subgroup of the patients (n = 10) received treatment with a dexamethasone/tobramycin 1 + 3 mg/mL ophthalmic suspension (Tobradex ® ) for 3 weeks and collection of tear film samples was repeated. The samples were analysed with label-free quantification nano liquid chromatography-tandem mass spectrometry requiring quantification in at least 70% of the samples in each group. Proteins were considered differentially expressed if p < 0.05., Results: Following Tobradex ® intervention, 27 proteins were upregulated while 61 proteins were downregulated. Regulated proteins after Tobradex ® treatment were involved in intermediate filament cytoskeleton organization including downregulation of the plakin proteins envoplakin, epiplakin and periplakin. Plectin, a protein of the plakin family, remained unchanged after Tobradex ® therapy. Tobradex ® treatment resulted in the regulation of proteins involved in translation including a cluster of downregulated ribosomal proteins. Tobradex ® intervention was associated with the regulation of proteins involved in fructose metabolism and glycolytic processes including fructose-1.6-bisphosphatase 1, fructose-bisphosphate aldolases A and B, pyruvate kinase PKM and transketolase. Ig lambda chain V-I region, prominin-1, and protein Niban were upregulated after Tobradex ® treatment., Conclusions: Tobradex treatment reversed the expression of plakin proteins in anterior blepharitis. Topical solutions which inhibit the expression of plakin proteins may have the potential to restore the ocular surface integrity in anterior blepharitis and should be explored further., (© 2023 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Insulin-like growth factor-1 (IGF-1) is a pleiotropic molecule with neurotrophic and immunomodulatory functions. Knowing the capacity of chronically activated microglia to produce IGF-1 may therefore show essential to promote beneficial microglial functions in Alzheimer's disease (AD). Here, we investigated the expression of IGF-1 mRNA and IGF-1 along with the expression of tumor necrosis factor (TNF) mRNA, and the amyloid-β (Aβ) plaque load in the hippocampus of 3- to 24-month-old APP swe /PS1 ΔE9 transgenic (Tg) and wild-type (WT) mice. As IGF-1, in particular, is implicated in neurogenesis we also monitored the proliferation of cells in the subgranular zone (sgz) of the dentate gyrus. We found that the Aβ plaque load reached its maximum in aged 21- and 24-month-old APP swe /PS1 ΔE9 Tg mice, and that microglial reactivity and hippocampal IGF-1 and TNF mRNA levels were significantly elevated in aged APP swe /PS1 ΔE9 Tg mice. The sgz cell proliferation decreased with age, regardless of genotype and increased IGF-1/TNF mRNA levels. Interestingly, IGF-1 mRNA was expressed in subsets of sgz cells, likely neuroblasts, and neurons in both genotypes, regardless of age, as well as in glial-like cells. By double in situ hybridization these were shown to be IGF1 mRNA + CD11b mRNA + cells, i.e., IGF-1 mRNA-expressing microglia. Quantification showed a 2-fold increase in the number of microglia and IGF-1 mRNA-expressing microglia in the molecular layer of the dentate gyrus in aged APP swe /PS1 ΔE9 Tg mice. Double-immunofluorescence showed that IGF-1 was expressed in a subset of Aβ plaque-associated CD11b + microglia and in several subsets of neurons. Exposure of primary murine microglia and BV2 cells to Aβ 42 did not affect IGF-1 mRNA expression. IGF-1 mRNA levels remained constant in WT mice with aging, unlike TNF mRNA levels which increased with aging. In conclusion, our results suggest that the increased IGF-1 mRNA levels can be ascribed to a larger number of IGF-1 mRNA-expressing microglia in the aged APP swe /PS1 ΔE9 Tg mice. The finding that subsets of microglia retain the capacity to express IGF-1 mRNA and IGF-1 in the aged APP swe /PS1 ΔE9 Tg mice is encouraging, considering the beneficial therapeutic potential of modulating microglial production of IGF-1 in AD.