Heyingwuzi formulation alleviates diabetic retinopathy by promoting mitophagy via the HIF-1α/BNIP3/NIX axis.

BACKGROUND: Diabetic retinopathy (DR) is the primary cause of visual problems in patients with diabetes. The Heyingwuzi formulation (HYWZF) is effective against DR. AIM: To determine the HYWZF prevention mechanisms, especially those underlying mitophagy. METHODS: Human retinal capillary endothelial cells (HRCECs) were treated with high glucose (hg), HYWZF serum, PX-478, or Mdivi-1 in vitro. Then, cell counting kit-8, transwell, and tube formation assays were used to evaluate HRCEC proliferation, invasion, and tube formation, respectively. Transmission electron microscopy was used to assess mitochondrial morphology, and Western blotting was used to determine the protein levels. Flow cytometry was used to assess cell apoptosis, reactive oxygen species (ROS) production, and mitochondrial membrane potential. Moreover, C57BL/6 mice were established in vivo using streptozotocin and treated with HYWZF for four weeks. Blood glucose levels and body weight were monitored continuously. Changes in retinal characteristics were evaluated using hematoxylin and eosin, tar violet, and periodic acid-Schiff staining. Protein levels in retinal tissues were determined via Western blotting, immunohistochemistry, and immunostaining. RESULTS: HYWZF inhibited excessive ROS production, apoptosis, tube formation, and invasion in hg-induced HRCECs via mitochondrial autophagy in vitro. It increased the mRNA expression levels of BCL2-interacting protein 3 (BNIP3), FUN14 domain-containing 1, BNIP3-like (BNIP3L, also known as NIX), PARKIN, PTEN-induced kinase 1, and hypoxia-inducible factor (HIF)-1α. Moreover, it downregulated the protein levels of vascular endothelial cell growth factor and increased the light chain 3-II/I ratio. However, PX-478 and Mdivi-1 reversed these effects. Additionally, PX-478 and Mdivi-1 rescued the effects of HYWZF by decreasing oxidative stress and apoptosis and increasing mitophagy. HYWZF intervention improved the symptoms of diabetes, tissue damage, number of acellular capillaries, and oxidative stress in vivo. Furthermore, in vivo experiments confirmed the results of in vitro experiments. CONCLUSION: HYWZF alleviated DR and associated damage by promoting mitophagy via the HIF-1α/BNIP3/NIX axis.

Application of optical coherence tomography and keratograph in the measurements of lower lid margin thickness.

PURPOSE: This study aims to investigate the applicability of lower lid margin thickness (LLMT) measurements in adults with and without meibomian gland dysfunction (MGD) by optical coherence tomography (OCT) and keratograph. METHODS: This is a cross-sectional, observational study. A hundred and eight volunteers aged 20 to 79, including 68 MGD patients and 40 normal subjects, were recruited. Using OCT and keratograph to measure the LLMT from the posterior lash line to anterior edge or outer edge of the tear meniscus was separately performed two times by the same person. RESULTS: The mean age of normal and MGD subjects was 50.5 ± 14.2 years and 55.8 ± 15.5 years, respectively. The LLMT with OCT and keratograph in MGD patients was significantly greater than that in normal subjects (1.06 ± 0.27 and 1.03 ± 0.25 mm vs. 0.90 ± 0.20 and 0.86 ± 0.16 mm, respectively). In both normal and MGD subjects, the tear meniscus height and LLMT with OCT were both greater than that with keratograph (P < 0.05), and intraclass correlation coefficient (ICC) demonstrated a good agreement in the LLMT measurements between two devices (ICC = 0.83 and 0.79, respectively). Additionally, the LLMT in MGD patients was appeared to be positively correlated with meiboscore (rs = 0.37, P = 0.002). CONCLUSIONS: The OCT and keratograph were two reliable tools in the LLMT measurements, which may have potential applications for diagnosis and evaluation of MGD. Furthermore, we found that the LLMT measured by OCT was greater than that measured by keratograph.

Bie-Jia-Ruan-Mai-Tang, a Chinese Medicine Formula, Inhibits Retinal Neovascularization in Diabetic Mice Through Inducing the Apoptosis of Retinal Vascular Endothelial Cells.

Proliferative diabetic retinopathy (PDR) is one of the main complications of diabetes, mainly caused by the aberrant proliferation of retinal vascular endothelial cells and the formation of new blood vessels. Traditional Chinese medicines possess great potential in the prevention and treatment of PDR. Bie-Jia-Ruan-Mai-Tang (BJ), a Chinese medicine formula, has a good therapeutic effect on PDR clinically; however, the mechanism of action involved remains unclear. Therefore, we investigated the effect of BJ on PDR through in vitro and in vivo experiments. A diabetic mouse model with PDR was established by feeding a high-fat-high-glucose diet combined with an intraperitoneal injection of streptozotocin (STZ), while high-glucose-exposed human retinal capillary endothelial cells (HRCECs) were employed to mimic PDR in vitro. The in vivo experiments indicated that BJ inhibited the formation of acellular capillaries, decreased the expression of VEGF, and increased the level of ZO-1 in diabetic mice retina. In vitro experiments showed that high glucose significantly promoted cell viability and proliferation. However, BJ inhibited cell proliferation by cycle arrest in the S phase, thus leading to apoptosis; it also increased the production of ROS, decreased the mitochondrial membrane potential, reduced the ATP production, and also reduced the expressions of p-PI3K, p-AKT, and Bcl-xL, but increased the expressions of Bax and p-NF-κB. These results suggest that BJ induces the apoptosis of HRCECs exposed to high glucose through activating the mitochondrial death pathway by decreasing the PI3K/AKT signaling and increasing the NF-κB signaling to inhibit the formation of acellular capillaries in the retina, thus impeding the development of PDR.

Effect of the Meibomian Gland Squeezer for Treatment of Meibomian Gland Dysfunction.

PURPOSE: To investigate the effect of the meibomian gland squeezer for treatment of meibomian gland dysfunction (MGD). METHODS: Seventy patients (140 eyes) with MGD were randomly divided into 2 groups: 36 patients who were treated by the meibomian gland squeezer as the treatment group and 34 patients were selected as the control group. Patients were evaluated at baseline, and 2-week and 1-month visits for subjective symptoms, objective signs and pain assessments, including ocular symptom scores, Ocular Surface Disease Index, tear breakup time, corneal fluorescein staining, Schirmer scores with no anesthetic (Schirmer I test), meibum quality, meibum expressibility, and Numeric Rating Scale-11. RESULTS: Sixty-five patients were followed in the study, and mean (±SD) age was 57.0 (±12.6) years. Compared with baseline, the 2 groups had varying degrees of improvement in ocular symptom scores and Ocular Surface Disease Index at the 2-week and 1-month visits; there was a statistically significant difference between groups (P < 0.001). At the 1-month visit, the treatment group showed a greater improvement in the breakup time (3.8 ± 1.6 vs. 1.8 ± 1.0 seconds, P < 0.001), corneal fluorescein staining (-2.1 ± 2.13 vs. -0.9 ± 1.3, P = 0.03), Schirmer I test (5.3 ± 2.9 vs. 2.3 ± 2.8 mm, P < 0.001), meibum quality (-7.5 ± 2.9 vs. -5.3 ± 2.4, P = 0.004), and meibum expressibility (-1.2 ± 0.8 vs. -0.7 ± 0.4, P = 0.007). In the treatment group, the mean (±SD) of total pain scores was 2.4 ± 1.0, which indicated that mild pain was still predominant under topical anesthesia. CONCLUSIONS: The meibomian gland squeezer may be safe, effective, and helpful for treatment of MGD and may offer an attractive treatment option for some patients with MGD, although it can cause mild pain or discomfort.