Effect of intravitreal ranibizumab on fibrovascular membranes in patients with proliferative diabetic retinopathy.

AIM: To assess the effects of intravitreal ranibizumab (IVR) on angiogenesis and glial activity of the fibrovascular membrane (FVM) in patients with proliferative diabetic retinopathy (PDR). METHODS: Forty-two eyes from 42 patients with PDR requiring vitrectomy were included and divided into two groups: control group (n=16) did not receive IVR, while IVR group (n=26) underwent IVR 5d before vitrectomy. FVM specimens were collected by the same surgeon during the interventions. Histopathological morphology was examined by hematoxylin-eosin (H-E) staining and cell densities in the FVM was assessed. Microvessels were outlined by immunohistochemical staining of CD31 and microvessel density (MVD) assessed as an index of FVM angiogenesis. Dual-color immunofluorescence staining, and confocal microscopy was used to detect co-localization and relative expression levels of glial fibrillary acidic protein (GFAP) and α-smooth muscle actin (α-SMA) as markers of glial-mesenchymal transition (GMT). The GMT index (GI; ratio of relative GFAP/α-SMA expression) was used to semi-quantify the degree of GMT or glial activity of FVMs. RESULTS: H-E staining showed similar vascularization in both groups, with microvessels and scattered stromal cells in the matrix. Infiltrated cell densities did not differ significantly between the two groups (P>0.05). The MVD of the IVR group (130.62±15.46/mm2) was significantly lower than that of the controls (142.25±19.16/mm2, P<0.05). In both groups, all sections were strongly immunostained for GFAP and α-SMA. The Pearson's correlation coefficients (PCC) of intensity of automated pixel count of two markers indicated GFAP and α-SMA co-stained well and GMT participated in the remolding of FVMs in PDR. The mean relative GFAP expression in the IVR group was significantly lower, whereas that of α-SMA was significantly higher than in controls (P<0.05). GI in the IVR group (1.10±0.10) was significantly lower than in the controls (1.21±0.12, P<0.05). CONCLUSION: IVR can reduce angiogenesis, glial activity of FVM and promote glial-fibrotic transformation by reducing MVD and promoting GMT but does not decrease the cell density in patients with PDR.

Variations of Flavone Glycosides Profile Underscore the Necessity of Quality Control of Prepared Microctis Folium Slices.

Microctis Folium (MF), the dried leaves of Microcos paniculata, is widely used as a medical and food dual-purpose herb in South-east Asia and China. However, the quality control of MF is not well studied. A simple and reliable quality control method was urgently needed for its growing usage. Herein, at first, its main active components were identified by UPLC-ESI-qTOF-MS, and a representative MF flavone glycosides profile consisting of ten compounds was illustrated, which is the most detailed one up to now. Successively, using vitexin as the reference substance, a novel QAMS method with HPLC for quantification of the ten identified flavone glycosides was developed and methodologically validated. Furthermore, making use of the abovementioned QAMS method, quantitative profiling of 21 batches of prepared MF slices collected from different hospital pharmacies were performed. As a result, the total contents of ten flavone glucosides and the content of specific compound showed obvious variations. Using the ten compounds' contents dataset, the 21 batches of samples were divided into two distinct clusters by HCA. In sum, our results indicated that it was of great importance to take quality control of prepared MF slices and we presented a robust and simple method for their quantitative determination, which should be beneficial for the quality control of MF and its derived products.

A comparative study between Chinese propolis and Brazilian green propolis: metabolite profile and bioactivity.

Among different types, Chinese propolis (ChPs) and Brazilian green propolis (BrGPs) have been shown to contain multi-functional properties. Despite extensive research in the field, reports comparing propolis from different geographical areas are still limited, compromising our current understanding of the potential therapeutic effect associated with propolis and its derived compounds. Herein, a comparative study between ChPs and BrGPs including their metabolite profile and bioactivities was performed. Interestingly, even when ChPs and BrGPs showed similar anti-inflammatory potential, our results showed that they contained very different levels of ethanol extract, total flavonoids and total phenolic acids and in fact, LC-MS metabolic profiling and pattern recognition could effectively distinguish ChPs and BrGPs. Moreover, all the propolis samples tested showed good anti-oxidant activity and no significant difference of free radical scavenging capacity existed between ChPs and BrGPs. In conclusion, ChPs and BrGPs have a distinct chemome, but their antioxidant and anti-inflammatory activities are similar.

Chronic photodamage in the chicken retina using 650-nm semiconductor laser.

AIM: To investigate the occurrence of chronic photodamage in the cone-based retina, following long-term exposure to a 650-nm semiconductor laser (power: 2 mW). METHODS: Chickens fed for 1mo under natural light after hatching were irradiated with 650-nm laser light at different times each day. Fifteen animals were included in each group. Group A was a control group, irradiated with natural light during the entire study. Group B was irradiated with laser for 3 min/d. Group C was irradiated with laser for 6 min/d. Group D was irradiated with laser for 30 min/d. The duration of the light experiment was 6mo. We obtained data at 1, 3, and 6mo, including measuring the retinal thickness in vivo using optical coherence tomography, hematoxylin and eosin staining, TUNEL assay, apoptosis staining, malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, and Western blotting to detect changes in L/M opsins and rhodopsin. RESULTS: At 1mo, the MDA content in Group D was higher than that observed in Group A (P=0.019). At 3mo the MDA content in Groups C and D was higher than that reported in Group A (P=0.026, 0.003). At 6mo, the MDA content in Groups B, C, and D was higher than that observed in Group A (P=0.038, 0.032, 0.000, respectively). There was no difference in SOD activity, and L/M opsin and rhodopsin content between the groups at 1 and 3mo. The SOD activity in group D was significantly decreased at 6mo (P=0.000), as was the content of rhodopsin. There was no significant reduction observed in retinal thickness, abnormal cell arrangement, and positive staining of TUNEL in the groups during the 6-month study period. CONCLUSION: Irradiation using a 650 nm semiconductor laser (power: 2 mW) for 6min per day over 6mo do not cause photodamage. Similarly, a 3-month exposure of 30min per day do not cause damage. However, irradiation for 6mo resulted in a significant increase in the content of free radicals and a decrease in the content of rhodopsin in the retina, suggesting the presence of photodamage.

Squamosamide derivative FLZ inhibits TNF-α-induced ICAM-1 expression via down-regulation of the NF-κB signaling pathway in ARPE-19 cells.

Dysfunction of the retinal pigment epithelium (RPE) resulting from chronic inflammation is implicated in the pathogenesis of age-related macular degeneration (AMD). It has been reported that tumor necrosis factor-α (TNF-α) could induce intercellular adhesion molecule-1 (ICAM-1) expression in RPE cells. FLZ, a novel synthetic squamosamide derivative from a Chinese herb, Annona glabra, has displayed significant anti-inflammatory activity. However, the effects of FLZ on TNF-α-induced ICAM-1 expression in RPE cells remain unknown. Therefore, in the present study, we evaluated the effects of FLZ on TNF-α-induced ICAM-1 expression in RPE cells. We found that FLZ prevented TNF-α-induced ICAM-1 expression and the ability of monocytes to adhere to ARPE-19 cells induced by TNF-α. Furthermore, FLZ inhibited TNF-α-induced NF-κB p65 expression, as well as phosphorylation of IκBα in ARPE-19 cells. Taken together, these results suggest that FLZ inhibited TNF-α-induced ICAM-1 expression through blocking NF-κB signaling pathway in ARPE-19 cells. Thus, FLZ could be used for designing novel therapeutic agents against AMD.