SIRT1 Deletion Impairs Retinal Endothelial Cell Migration Through Downregulation of VEGF-A/VEGFR-2 and MMP14

JMJD3 and SNAI2 synergistically protect against Parkinson's disease by mediating the YAP/HIF1α signaling pathway in a mouse model

This study aimed to characterize the functional relevance and mechanistic basis of the histone demethylase Jumonji domain-containing protein-3 (JMJD3) in preserving dopaminergic neuron survival in Parkinson's disease (PD). Mice with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced lesions and MN9D dopaminergic neuronal cell lines exposed to 6-OHDA, respectively, were used to simulate in vivo and in vitro PD-like environments. PD-related genes with differential expressions were identified using RNA sequencing of hippocampal tissues collected from MPTP-lesioned mice. A specific lentiviral shRNA vector was used to investigate the effects of JMJD3 on neuron activities in vitro and PD-like phenotypes in vivo. JMJD3 was found to up-regulate the expression of Snail family transcriptional repressor 2 (SNAI2) through the inhibition of H3 on lysine 27 (H3K27me3) enrichment in the SNAI2 promoter region. As a result, the viability of 6-OHDA-exposed MN9D cells was stimulated, and cell apoptosis was diminished. Knockdown of SNAI2 decreased the expression of yes-associated protein (YAP) and HIF1α while also reducing the viability of 6-OHDA-exposed MN9D cells and increasing cell apoptosis. The in vivo experiments demonstrated that JMJD3 activated the SNAI2/YAP/HIF1α signaling pathway, inhibiting PD-like phenotypes in MPTP-lesioned mice. Thus, the findings provide evidence that JMJD3 inhibits the enrichment of H3K27me3 at the SNAI2 promoter, leading to the upregulation of SNAI2 expression and activation of the YAP/HIF1α signaling pathway, ultimately exerting a protective effect on PD mice. This finding suggests that targeting the JMJD3-SNAI2 pathway could be a promising therapeutic strategy for PD. Further in-depth studies are needed to elucidate the underlying mechanisms and identify potential downstream targets of this pathway.

METTL3-Mediated RNA m6A Modification Regulates the Angiogenic Behaviors of Retinal Endothelial Cells by Methylating MMP2 and TIE2

Purpose

N6-methyladenosine (m6A) is a commonly occurring modification of mRNAs, catalyzed by a complex containing methyltransferase like 3 (METTL3). Our research aims to explore how METTL3-dependent m6A modification affects the functions of retinal endothelial cells (RECs).

Methods

An oxygen-induced retinopathy (OIR) mouse model was established, and RECs were isolated using magnetic beads method. Human retinal microvascular endothelial cells (HRMECs) were treated with normoxia (21% O2) or hypoxia (1% O2). Dot blot assay determined m6A modification levels. Quantitative RT-PCR and Western blot detected the mRNA and protein expression levels of the target candidates, respectively. Genes were knocked down by small interfering RNA transfection. Matrigel-based angiogenesis and transwell assays evaluated the abilities of endothelial tube formation and migration, respectively. Methylated RNA immunoprecipitation-qPCR determined the levels of m6A modification in the target genes.

Results

The m6A modification levels were significantly upregulated in the retinas and RECs of OIR mice. Exposure to hypoxia significantly elevated both METTL3 expression and m6A modification levels in HRMECs. METTL3 knockdown curtailed endothelial tube formation and migration in vitro under both normoxic and hypoxic conditions. Concurrently, this knockdown in HRMECs resulted in reduced m6A modification levels of MMP2 and TIE2 transcripts, subsequently leading to a decrease in their respective protein expressions. Notably, knockdown of MMP2 and TIE2 also markedly inhibited the angiogenic activities of HRMECs.

Conclusions

METTL3-mediated m6A modification promotes the angiogenic behaviors of RECs by targeting MMP2 and TIE2, suggesting its significance in retinal angiogenesis and METTL3 as a potential therapeutic target.

BZD9L1 benzimidazole analogue hampers colorectal tumor progression by impeding angiogenesis

BACKGROUND

The development of new vasculatures (angiogenesis) is indispensable in supplying oxygen and nutrients to fuel tumor growth. Epigenetic dysregulation in the tumor vasculature is critical to colorectal cancer (CRC) progression. Sirtuin (SIRT) enzymes are highly expressed in blood vessels. BZD9L1 benzimidazole analogue is a SIRT 1 and 2 inhibitor with reported anticancer activities in CRC. However, its role has yet to be explored in CRC tumor angiogenesis.

AIM

To investigate the anti-angiogenic potential of BZD9L1 on endothelial cells (EC) in vitro, ex vivo and in HCT116 CRC xenograft in vivo models.

METHODS

EA.hy926 EC were treated with half inhibitory concentration (IC₅₀) (2.5 μM), IC₅₀ (5.0 μM), and double IC₅₀ (10.0 μM) of BZD9L1 and assessed for cell proliferation, adhesion and SIRT 1 and 2 protein expression. Next, 2.5 μM and 5.0 μM of BZD9L1 were employed in downstream in vitro assays, including cell cycle, cell death and sprouting in EC. The effect of BZD9L1 on cell adhesion molecules and SIRT 1 and 2 were assessed via real-time quantitative polymerase chain reaction (qPCR). The growth factors secreted by EC post-treatment were evaluated using the Quantibody Human Angiogenesis Array. Indirect co-culture with HCT116 CRC cells was performed to investigate the impact of growth factors modulated by BZD9L1-treated EC on CRC. The effect of BZD9L1 on sprouting impediment and vessel regression was determined using mouse choroids. HCT116 cells were also injected subcutaneously into nude mice and analyzed for the outcome of BZD9L1 on tumor necrosis, Ki67 protein expression indicative of proliferation, cluster of differentiation 31 (CD31) and CD34 EC markers, and SIRT 1 and 2 genes via hematoxylin and eosin, immunohistochemistry and qPCR, respectively.

RESULTS

BZD9L1 impeded EC proliferation, adhesion, and spheroid sprouting through the downregulation of intercellular adhesion molecule 1, vascular endothelial cadherin, integrin-alpha V, SIRT1 and SIRT2 genes. The compound also arrested the cells at G1 phase and induced apoptosis in the EC. In mouse choroids, BZD9L1 inhibited sprouting and regressed sprouting vessels compared to the negative control. Compared to the negative control, the compound also reduced the protein levels of angiogenin, basic fibroblast growth factor, platelet-derived growth factor and placental growth factor, which then inhibited HCT116 CRC spheroid invasion in co-culture. In addition, a significant reduction in CRC tumor growth was noted alongside the downregulation of human SIRT1 (hSIRT1), hSIRT2, CD31, and CD34 EC markers and murine SIRT2 gene, while the murine SIRT1 gene remained unaffected, compared to vehicle control. Histology analyses revealed that BZD9L1 at low (50 mg/kg) and high (250 mg/kg) doses reduced Ki-67 protein expression, while BZD9L1 at the high dose diminished tumor necrosis compared to vehicle control.

CONCLUSION

These results highlighted the anti-angiogenic potential of BZD9L1 to reduce CRC tumor progression. Furthermore, together with previous anticancer findings, this study provides valuable insights into the potential of BZD9L1 to co-target CRC tumor vasculatures and cancer cells via SIRT1 and/or SIRT2 down-regulation to improve the therapeutic outcome.

Efficacy of puerarin in rats with focal cerebral ischemia through modulation of the SIRT1/HIF-1α/VEGF signaling pathway and its effect on synaptic plasticity

This study aimed to evaluate the efficacy of puerarin and its effect on synaptic plasticity in rats with focal cerebral ischemia (FCI) by modulating the silent mating type information regulation 2 homolog (SIRT1)/hypoxia-inducible factor-1α (HIF-1α)/vascular endothelial growth factor (VEGF) signaling pathway. Fifty specific pathogen-free-grade healthy male rats were randomly divided into sham operation group (SOG), model group, low-dose group, medium-dose group, and high-dose group, with 10 rats in each group. The SOG group received sham operation and saline treatment, while the other four groups received the same amount of saline, 25 mg/kg, 50 mg/kg, and 100 mg/kg of puerarin injection, respectively. After modeling, the rats exhibited higher neurological deficit, inflammation, cerebral infarction rate, and lower forelimb motor function as well as lower protein expressions of SIRT1, HIF-1α, VEGF, synaptophysin (SYN), and postsynaptic density protein (PSD)-95. With the treatment of different doses of puerarin, the degree of neurological impairment, impaired motor function, cerebral infarction rate, and the levels of inflammatory factors (interleukin [IL]-1β, IL-6, and intercellular adhesion molecule 1) in brain tissues were reduced; the protein expressions of SIRT1, HIF-1α, VEGF, SYN, and PSD-95 in brain tissues were enhanced, and the synaptic volume density, numerical density, surface density, width of synaptic cleft, and curvature of the synaptic interface in the cerebral cortex were also improved. Notably, the effects of puerarin on the above-mentioned indicators were dose-dependent. Puerarin can improve neurological impairment and forelimb motor function, reduce inflammatory response, inhibit brain edema, regulate synaptic plasticity, and restore the curvature of synaptic interface in rats with FCI, and its mechanism of action may be related to the activation of SIRT1/HIF-1α/VEGF signaling pathway.

Resistance exercise promotes the resolution and recanalization of deep venous thrombosis in a mouse model via SIRT1 upregulation

BACKGROUND

Early exercise for acute deep venous thrombosis (DVT) improves the patient's symptoms and does not increase the risk of pulmonary embolism. However, information about its effect on thrombus resolution is limited. The aim of this study was to investigate the role of resistance exercise (RE) in thrombus resolution and recanalization and determine its underlying mechanisms.  METHODS: Ninety-six C57BL/6 J mice were randomly divided into four groups: Control group (C, n = 24); DVT group (D, n = 24); RE + DVT group (ED, n = 24); and inhibitor + RE + DVT group (IED, n = 24). A DVT model was induced by stenosis of the inferior vena cava (IVC). After undergoing IVC ultrasound within 24 h post-operation to confirm DVT formation, mice without thrombosis were excluded. Other mice were sacrificed and specimens were obtained 14 or 28 days after operation. Thrombus-containing IVC was weighed, and the thrombus area and recanalization rate were calculated using HE staining. Masson's trichrome staining was used to analyze the collagen content. RT-PCR and ELISA were performed to examine IL-6, TNF-α, IL-10, and VEGF expression levels. SIRT1 expression was assessed using immunohistochemistry staining and RT-PCR. VEGF-A protein expression and CD-31-positive microvascular density (MVD) in the thrombus were observed using immunohistochemistry.  RESULTS: RE did not increase the incidence of pulmonary embolism. It reduced the weight and size of the thrombus and the collagen content. Conversely, it increased the recanalization rate. It also decreased the levels of the pro-inflammatory factors IL-6 and TNF-α and increased the expression levels of the anti-inflammatory factor IL-10. RE enhanced VEGF and SIRT1 expression levels and increased the MVD in the thrombosis area. After EX527 (SIRT1 inhibitor) was applied, the positive effects of exercise were suppressed.

CONCLUSIONS

RE can inhibit inflammatory responses, reduce collagen deposition, and increase angiogenesis in DVT mice, thereby promoting thrombus resolution and recanalization. Its underlying mechanism may be associated with the upregulation of SIRT1 expression.

Sirt1 Regulates Corneal Epithelial Migration by Deacetylating Cortactin

Purpose

Silent information regulator 1 (SIRT1) is a nicotinamide adenine dinucleotide (NAD+) dependent deacetylase, which plays an essential role in cellular metabolism, autophagy, and chromatin accessibility. Our study aimed to determine its role in controlling corneal epithelial wound healing (CEWH).

Methods

Corneal epithelial (CE)–specific Sirt1 deletion mice were created using the Cre-lox system. CE debridement was used to create a CEWH model. Corneal epithelial cells (CECs) were collected with an Algerbrush. Western blot analysis and RT-qPCR were performed to determine protein and mRNA expression levels. SiRNA transfection technology knocked down SIRT1 and cortactin expression levels in human corneal epithelial cells. Scratch wound assay, MTS assay, and TUNEL assay determined cell migratory, proliferative, and apoptotic behavior, respectively. Co-immunoprecipitation probed for SIRT1 and cortactin interaction. Immunofluorescence staining evaluated the location and expression levels of SIRT1, cortactin, acetylated-cortactin, and F-actin.

Results

During CEWH, increases in SIRT1 mRNA and protein expression levels accompanied the downregulation of acetylated lysine in non-histone proteins. The loss of SIRT1 function reduced cell migration and, in turn, delayed CEWH. SIRT1 bound to and deacetylated cortactin in vitro and in vivo. Loss of either SIRT1 or cortactin suppressed wound edge lamellipodia formation, which is consistent with migration retardation.

Conclusions

During CEWH, SIRT1 upregulation and its modification of cortactin boost CEC migration by increasing the development of lamellipodia at the wound edge. Therefore SIRT1 may serve as a potential target to enhance CEWH.

Transcription Factor ChREBP Mediates High Glucose-Evoked Increase in HIF-1α Content in Epithelial Cells of Renal Proximal Tubules

Hyperglycemia/diabetes appears to be accompanied by the state of hypoxia, which especially affects kidneys. The aim of the study was to elucidate the mechanism of high glucose action on HIF-1α expression in renal proximal tubule epithelial cells. The research hypotheses included: (1) the participation of transcription factor ChREBP; and (2) the involvement of the effects resulting from pseudohypoxia, i.e., lowered intracellular NAD+/NADH ratio. The experiments were performed on HK-2 cells and primary cells: D-RPTEC (Diseased Human Renal Proximal Tubule Epithelial Cells—Diabetes Type II) and RPTEC (Renal Proximal Tubule Epithelial Cells). Protein and mRNA contents were determined by Western blot and RT-qPCR, respectively. ChREBP binding to DNA was detected applying chromatin immunoprecipitation, followed by RT-qPCR. Gene knockdown was performed using siRNA. Sirtuin activity and NAD⁺/NADH ratio were measured with commercially available kits. It was found that high glucose in HK-2 cells incubated under normoxic conditions: (1) activated transcription of HIF-1 target genes, elevated HIF-1α and ChREBP content, and increased the efficacy of ChREBP binding to promoter region of HIF1A gene; and (2), although it lowered NAD⁺/NADH ratio, it affected neither sirtuin activity nor HIF-1α acetylation level. The stimulatory effect of high glucose on HIF-1α expression was not observed upon the knockdown of ChREBP encoding gene. Experiments on RPTEC and D-RPTEC cells demonstrated that HIF-1α content in diabetic proximal tubular cells was lower than that in normal ones but remained high glucose-sensitive, and the latter phenomenon was mediated by ChREBP. Thus, it is concluded that the mechanism of high glucose-evoked increase in HIF-1α content in renal proximal tubule endothelial cells involves activation of ChREBP, indirectly capable of HIF1A gene up-regulation.

Geniposide downregulates the VEGF/SphK1/S1P pathway and alleviates angiogenesis in rheumatoid arthritis in vivo and in vitro

The VEGF/SphK1/S1P pathway is closely related to angiogenesis in rheumatoid arthritis (RA), but the precise underlying mechanisms are unclear at present. Here, we explored the involvement of the VEGF/SphK1/S1P cascade in RA models and determined the effects of GE intervention. Our results showed abnormal expression of proteins related to this pathway in RA synovial tissue. Treatment with GE effectively regulated the signal axis, inhibited angiogenesis, and alleviated RA symptoms. In vitro, TNF-ɑ enhanced the VEGF/SphK1/S1P pathway in a co-culture model of fibroblast-like synoviocytes (FLS) and vascular endothelial cells (VEC). GE induced downregulation of VEGF in FLS, restored the dynamic balance of pro-/antiangiogenic factors, and suppressed SphK1/S1P signaling in VEC, resulting in lower proliferation activity, migration ability, tube formation ability, and S1P secretion ability of VEC cells. Additionally, SphK1-specific small interfering RNA (siRNA) blocked the VEGF/SphK1/S1P cascade, which can effectively alleviate the stimulatory effect of FLS on VEC and further enhanced the therapeutic effect of GE. Taken together, our results demonstrate that GE suppresses the VEGF/SphK1/S1P pathway and alleviates the stimulation of VEC by FLS, thereby preventing angiogenesis and promoting therapeutic effects against RA.

Melatonin exerts protective effects on diabetic retinopathy via inhibition of Wnt/β-catenin pathway as revealed by quantitative proteomics

Diabetic retinopathy (DR), the most common ocular complication resulting from diabetes in working-age adults, causes vision impairment and even blindness because of microvascular damage to the retina. Melatonin is an endogenous neurohormone possessing various biological properties, including the regulation of oxidative stress, inflammation, autophagy, and angiogenesis functions. To evaluate the effects of melatonin on DR, we first investigated the role of melatonin in retinal angiogenesis and inner blood-retina barrier (iBRB) under high glucose conditions in vitro and in vivo. Melatonin administration ameliorated high glucose-induced iBRB disruption, cell proliferation, cell migration, invasion and tube formation, and decreased the expression levels of VEGF, MMP-2, and MMP-9. Furthermore, melatonin treatment increased the level of autophagy but decreased the expression levels of inflammation-related factors under high glucose conditions. To further explore the underlying mechanism, we evaluated human retinal microvascular endothelial cells (HRMECs) via tandem mass tags (TMT)-labeled quantitative proteomics under high-glucose conditions with or without melatonin. Bioinformatics analysis results revealed that the main enrichment pathway of differentially expressed proteins (DEPs) was the Wnt pathway. We found that melatonin inhibited the activation of Wnt/β-catenin pathway following DR. These abovementioned protective effects of melatonin under hyperglycemia were blocked by lithium chloride (LiCl; activator of the Wnt/β-catenin signaling pathway). In summary, melatonin exerts protective effects on experimental DR via inhibiting Wnt/β-catenin pathway by, at least partially, alleviating autophagic dysfunction and inflammatory activation.

Melatonin Lowers HIF-1α Content in Human Proximal Tubular Cells (HK-2) Due to Preventing Its Deacetylation by Sirtuin 1

Although melatonin is widely known for its nephroprotective properties, there are no reports clearly pointing at its impact on the activity of hypoxia-inducible factor-1 (HIF-1), the main mediator of metabolic responses to hypoxia, in kidneys. The aim of the present study was to elucidate how melatonin affects the expression of the regulatory subunit HIF-1α in renal proximal tubules. HK-2 cells, immortalized human proximal tubular cells, were cultured under hypoxic conditions (1% O₂). Melatonin was applied at 100 μM concentration. Protein and mRNA contents were determined by Western blot and RT-qPCR, respectively. HIF-1α acetylation level was established by means of immunoprecipitation followed by Western blot. Melatonin receptors MT1 and MT2 localization in HK-2 cells was visualized using immunofluorescence confocal analysis. It was found that melatonin in HK-2 cells (1) lowered HIF-1α protein, but not mRNA, content; (2) attenuated expression of HIF-1 target genes; (3) increased HIF-1α acetylation level; and (4) diminished sirtuin 1 expression (both protein and mRNA). Sirtuin 1 involvement in the regulation of HIF-1α level was confirmed applying cells with silenced Sirt1 gene. Moreover, the presence of membrane MT1 and MT2 receptors was identified in HK-2 cells and their ligand, ramelteon, turned out to mimic melatonin action on both HIF-1α and sirtuin 1 levels. Thus, it is concluded that the mechanism of melatonin-evoked decline in HIF-1α content in renal proximal tubular cells involves increased acetylation of this subunit which results from the attenuated expression of sirtuin 1, an enzyme reported to deacetylate HIF-1α. This observation provides a new insight to the understanding of melatonin action in kidneys.

Basic Fibroblast Growth Factor Attenuates Injury in Myocardial Infarction by Enhancing Hypoxia-Inducible Factor-1 Alpha Accumulation

Background

The combination of antiapoptotic and angiogenic actions may represent a pharmacotherapeutic strategy for the treatment of myocardial infarction. Fibroblast growth factor (FGF) is expressed in various cell types including endothelial and muscle cells and promotes their survival, migration, and proliferation.

Methods and Results

Myocardial microvascular endothelial cells were divided into four treatment groups, the sham, hypoxia, basic FGF (bFGF), and bFGF plus 2-methoxyestradiol groups, and subjected to in vitro apoptotic analysis and Matrigel assays. An in vivo model of myocardial infarction was established by ligaturing the left coronary artery of mice in the four treatment groups. Cardiac performance, myocardial injury, endothelial cell angiogenesis, and myocardial apoptosis were assessed. bFGF administration after myocardial infarction improved cardiac function and cell viability, attenuated myocardial injury and apoptosis, and enhanced angiogenesis. Western blotting of HIF-1α, p-AKT, VEGF, p53, BAX, and Bcl-2 showed that bFGF increased HIF-1α, p-AKT, VEGF, and Bcl-2 and decreased BAX protein levels.

Conclusion

The results of the present study indicated that bFGF attenuates myocardial injury by inhibiting apoptosis and promoting angiogenesis via a novel HIF-1α-mediated mechanism and a potential utility of bFGF in protecting against myocardial infarction.

Upregulation of miRNA-9-5p Promotes Angiogenesis after Traumatic Brain Injury by Inhibiting Ptch-1

MicroRNA-9-5p (miRNA-9-5p) is an important regulator of angiogenesis in many pathological states. However, the effect of miRNA-9-5p on angiogenesis after traumatic brain injury (TBI) has not been elucidated. In this study, a controlled cortical impact (CCI) model was used to induce TBI in Sprague-Dawley rats, and an oxygen glucose deprivation (OGD) model was used to mimic the pathological state in vitro. Brain microvascular endothelial cells (BMECs) were extracted from immature rats. The results showed that the level of miRNA-9-5p was significantly increased in the traumatic foci after TBI, and the upregulation of miRNA9-5p promoted the recovery of neurological function. Moreover, the upregulation of miRNA-9-5p with miRNA agomir significantly increased the density of the microvascular and neurons around the traumatic foci in rats after TBI. The results of the in vitro experiments confirmed that the upregulation of miRNA-9-5p with a miRNA mimic improved cellular viability and alleviated cellular apoptosis. Dual luciferase reporter assay validated that miRNA-9-5p was a posttranscriptional modulator of Ptch-1. Activation of the Hedgehog pathway by increasing the level of miRNA-9-5p promoted the migration and tube formation of BMECs in vitro. In addition, we found that the upregulation of miRNA-9-5p activated the Hedgehog pathway and increased the phosphorylation of AKT, which promoted the expression of cyclin D1, MMP-9 and VEGF in BMECs. All these results indicate that the upregulation of miRNA-9-5p promotes angiogenesis and improves neurological functional recovery after TBI, mainly by activating the Hedgehog pathway. MiRNA-9-5p may be a potential new therapeutic target for TBI.

Therapeutic Effect of Abelmoschus manihot on Type 2 Diabetic Nonproliferative Retinopathy and the Involvement of VEGF

Objective

To evaluate the efficacy of Abelmoschus manihot in treating type 2 diabetic nonproliferative retinopathy.

Methods

It was a randomized controlled clinical trial. The recruited eighty subjects with type 2 diabetic nonproliferative retinopathy were randomly divided into treatment group and control group. The two groups received basic treatments including control of blood glucose, blood pressure and blood lipid, management of diet, exercise and health education, and monitoring of relevant indicators. Additionally, the treatment group was given oral administration of Abelmoschus manihot. All subjects were followed up on monthly basis for consecutive six months. The related parameters including diabetic retinopathy (DR) incidence rates, “Early Treatment Diabetic Retinopathy Study” (ETDRS) vision scores, retinal thicknesses in macular region, serum vascular endothelial growth factor (VEGF) levels, and biochemical indicators of both groups before and after treatment were accurately collected and statistically analyzed.

Results

There were no significant differences of DR severity levels, ETDRS vision scores, macular retinal thicknesses such as cube average thickness (CAT), central subfield thickness (CST), and cube volume (CV), and serum VEGF levels between two groups before treatment. Meanwhile, there were no significant differences of demographic characteristics, case terminations, blood glucose, blood lipid, blood pressure, biochemical indicators of hepatorenal function, hypoglycemic drugs, hypotensive drugs, and other basic treatments between two groups during six months treatment. The present study suggested that the remission rate of DR and the ETDRS vision score in the treatment group were significantly higher than those of the control group (remission rate: 25.4% vs 9.3%, P=0.01; ETDRS score: 78 (72, 82) vs 72 (67, 80), P=0.0002) while the progression rate of DR in the treatment group was significantly lower than that of the control group (progression rate: 4.2% vs 18.7%, P=0.007) after six months treatment. In addition, the CAT, CST, CV, and serum VEGF levels of the treatment group were significantly improved after the treatment (CAT: 286 (278, 302) vs 282 (270, 295) μm, P < 0.0001; CST: 251 (239, 274) vs 248 (235, 265) μm, P < 0.0001; CV: 10.3 (10.0, 10.9) vs 10.1 (9.7, 10.6) mm³, P < 0.0001; VEGF: 0.21 (0.14, 0.58) vs 0.16 (0.10, 0.23) ng/ml, P=0.0026), while there were no significant differences of the control group before and after treatment (CAT: 287 (279, 294) vs 287 (279, 295) μm, P=0.27; CST: 250 (240, 266) vs 252 (238, 266) μm, P=0.72; CV: 10.4 (10.1, 10.6) vs 10.4 (10.1, 10.7) mm³, P=0.53; VEGF: 0.21 (0.13, 0.66) vs 0.23 (0.12, 0.64) ng/ml, P=0.85).

Conclusion

The study offered the novel evidence for the therapeutic effect of Abelmoschus manihot on type 2 diabetic nonproliferative retinopathy, which was associated with improved VEGF. This trial is registered with ChiCTR1800019292.