ABSTRACT
Objective:To investigate the changes of ocular surface microbiota in obese patients before and after dietary intervention.Methods:From November 1, 2020 to May 1, 2021, 35 obese patients in the obesity management center of the Department of Endocrinology and Metabolic Diseases of Henan Provincial People′s Hospital were selected for a 4-week low-calorie dietary intervention of 1 600-1 800 kcal/day. The body weight, body mass index(BMI), body composition(body fat, body fat percentage, visceral fat grade, total body water, and skeletal muscle) were observed before and after dietary intervention. The characteristics of ocular surface flora in obese patients before and after intervention were analyzed by 16S rRNA sequencing.Results:The body weight, BMI, body fat, percentage of body fat, visceral fat grade and total body water decreased significantly after 4 weeks( P<0.05), while there was no significant difference in skeletal muscle( P>0.05). There was no significant difference of ocular surface flora α and β in diversity( P>0.05). Opportunistic pathogens Pseudomonas and Cutibacterium decreased significantly, while Faecalibacterium, Lachnospiraceae NK4A136 group, Oscillospiraceae UCG 002, and Blautia, which producing short chain fatty acids, increased significantly( P<0.05). Functional prediction analysis showed that the metabolic pathways such as degradation related pathways and insulin signaling pathways of volatile organic compounds(VOCs) were significantly enriched. Conclusion:After dietary intervention, opportunistic pathogenic bacteria decreased and short chain fatty acid producing bacteria increased in obese patients. The altered ocular surface flora may be related to the degradation of VOCs and the improvement of insulin sensitivity.
ABSTRACT
Objective:To explore the changes of corneal neuropathy and ocular surface flora in patients with type 2 diabetes, and the correlation between corneal neuropathy and ocular surface flora changes.Methods:According to the results of fundus fluorescein angiography, 65 patients with type 2 diabetes (130 eyes in total) who were treated with insulin alone and without comorbid retinopathy in the Department of Endocrinology, Henan People′s Hospital from March to June 2019 were selected. Sixty-five age-matched normal glucose tolerance subjects (130 eyes in total) were also enrolled. Confocal microscopy was performed and conjunctival sac secretions were collected. Through 16S rRNA analysis and sequencing and PICRUSt bacterial gene function prediction, the relationship between patients with type 2 diabetes and the difference in the degree of corneal neuropathy and the composition of ocular surface flora and function prediction in healthy people were explored, and the correlation between corneal neuropathy and ocular surface flora was analyzed as well.Results:Compared with healthy people, patients with type 2 diabetes have more severe corneal neuropathy, and it was related to the changes in ocular surface flora. Brevibacillus and paenibacillus were significantly positively correlated with the degree of corneal neuropathy ( P<0.05), and enhydrobacter and proteobacteria were significantly negatively correlated with the degree of corneal neuropathy ( P<0.05). PICRUSt analysis showed that the degree of enrichment of metabolism-related genes in the ocular surface flora of patients with type 2 diabetes was significantly changed compared with healthy people. Conclusion:Patients with type 2 diabetes present with more severe corneal neuropathy. The diversity of ocular surface flora and metabolic function have significant changes. The degree of severity corneal neuropathy is related to brevibacillus, paenibacillus, enhydrobacter, and proteobacteria.