Bacterial Flora Changes in Conjunctiva of Rats with Streptozotocin-Induced Type I Diabetes

Abstract

BackgroundThe microbiota of both humans and animals plays an important role in their health and the development of disease. Therefore, the bacterial flora of the conjunctiva may also be associated with some diseases. However, there are no reports on the alteration of bacterial flora in conjunctiva of diabetic rats in the literature. Therefore, we investigated the changes in bacterial flora in bulbar conjunctiva of rats with streptozotocin (STZ)-induced type I diabetes.MethodsA high dose of STZ (60 mg/kg, i.p.) was injected into Sprague-Dawley (SD) rats to induce type I diabetes mellitus (T1DM). The diabetic rats were raised in the animal laboratory and at 8 months post-injection of STZ swab samples were taken from the bulbar conjunctiva for cultivation of aerobic bacteria. The bacterial isolates were identified by Gram staining and biochemical features. The identified bacteria from both diabetic and healthy rats were then compared.ResultsThe diabetic and healthy rats had different bacterial flora present in their bulbar conjunctiva. In total, 10 and 8 bacterial species were found in the STZ and control groups, respectively, with only three species (Enterococcus faecium, Enterococcus gallinarum and Escherichia coli) shared between the two groups. Gram-positive bacteria were common in both groups and the most abundant was Enterococcus faecium. However, after the development of T1DM, the bacterial flora in the rat bulbar conjunctiva changed considerably, with a reduced complexity evident.ConclusionsSTZ-induced diabetes caused alterations of bacterial flora in the bulbar conjunctiva in rats, with some bacterial species disappearing and others emerging. Our results indicate that the conjunctival bacterial flora in diabetic humans should be surveyed for potential diagnostic markers or countermeasures to prevent eye infections in T1DM patients.

Genistein prevention of hyperglycemia and improvement of glucose tolerance in adult non-obese diabetic mice are associated with alterations of gut microbiome and immune homeostasis

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“…3C) and six at the genus level (Fig. 3D) were significantly increased following GEN treatment, suggesting a pro-inflammatory effect (25, 27-29). In addition, we have found that two diets used in this study had a differential effect (indicated by α-diversity, β-diversity, and taxonomy) on gut microbiome in VH females, which is in agreement with previous literatures (30).…”

Eye of the Finch: characterization of the ocular microbiome of house finches in relation to mycoplasmal conjunctivitis

“…In contrast, the few vertebrate ocular microbiomes that have been characterized (humans, lab rats and koalas) were found to be dominated by members of the Phyla Actinobacteria and Proteobacteria (Dong et al ., ; Alfano et al ., ; Yang et al . ; Kugadas and Gadjeva, ; Shin et al ., ). Although Firmicutes have been identified in these microbiomes as well, they are at much lower relative abundance in comparison to the house finch ocular microbiome (Dong et al ., ; Lee et al ., ; Zhou et al ., ).…”

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The Protective Effect of L-arginine in Cisplatin-induced Nephrotoxicity in Streptozotocin-induced Diabetic Rats

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