Vascular Endothelial Growth Factor In Rats Research Articles

Glucoregulatory effect of butyrate is associated with elevated circulating VEGF and reduced cardiac lactate in high fructose fed rats

BackgroundHigh fructose diet has been linked with impaired body metabolism and cardiovascular diseases. Sodium butyrate (NaB) was documented to improve glucoregulation and cardiometabolic problems associated with high fructose diet (HFrD) but the mechanisms behind it are unclear. As a result, the purpose of this study was to look into the effects of NaB on VEGF and cardiac lactate in HFrD-induced dysmetabolism. MethodsTwenty male Wistar rats of weight 130–140 g were assigned randomly after a week of acclimation into four groups: Control diet (CTR), High fructose drink (HFrD); 10 % (w/v), NaB (200 mg/kg bw), and HFrD + NaB (200 mg/kg bw). The animals were induced to be unconscious with 50 mg/kg of pentobarbital sodium intraperitoneally, blood samples were taken via cardiac puncture and cardiac tissue homogenates were obtained for Fasting Blood Sugar (FBS) and plasma insulin, cardiac glycogen, plasma and cardiac glycogen synthase, plasma and cardiac nitric oxide as well as vascular endothelial growth factor (VEGF). ResultHFrD resulted in statistical elevation body and cardiac weight, plasma glucose, plasma insulin, cardiac lactate, glycogen and decreased nitric oxide level (NO) when compared with the control group. Administration of NaB reduced cardiac weight, blood glucose, plasma insulin, cardiac lactate while nitric oxide and glycogen increased (P < 0.05). NaB increased plasma glycogen synthase in normal rats, plasma and cardiac circulating VEGF in HFrD administered rats (P < 0.05) while no change was produced in plasma and cardiac glycogen synthase level of HFrD treated rats. ConclusionSodium butyrate improves glucoregulation by reducing cardiac lactate and increasing circulating VEGF in HFrD-treated rats.

Ebola virus disrupts the inner blood-retinal barrier by induction of vascular endothelial growth factor in pericytes.

Ebola virus (EBOV) causes severe hemorrhagic fever in humans with high mortality. In Ebola virus disease (EVD) survivors, EBOV persistence in the eyes may break through the inner blood-retinal barrier (iBRB), leading to ocular complications and EVD recurrence. However, the mechanism by which EBOV affects the iBRB remains unclear. Here, we used the in vitro iBRB model to simulate EBOV in retinal tissue and found that Ebola virus-like particles (EBO-VLPs) could disrupt the iBRB. Cytokine screening revealed that EBO-VLPs stimulate pericytes to secrete vascular endothelial growth factor (VEGF) to cause iBRB breakdown. VEGF downregulates claudin-1 to disrupt the iBRB. Ebola glycoprotein is crucial for VEGF stimulation and iBRB breakdown. Furthermore, EBO-VLPs caused iBRB breakdown by stimulating VEGF in rats. This study provides a mechanistic insight into that EBOV disrupts the iBRB, which will assist in developing new strategies to treat EBOV persistence in EVD survivors.

Suppressive role of vascular endothelial growth factor on intestinal apoptosis in induced necrotizing enterocolitis in rats.

Necrotizing enterocolitis (NEC) is a devastating disease that can cause mortality in preterm babies. NEC may develop through an apoptotic pathway that is known to be inhibited by vascular endothelial growth factor (VEGF). This study determined whether VEGF exerted a protective effect against the development of NEC and apoptosis in rats. To determine the effect of VEGF in NEC rats, neonatal rats were randomized into 4 groups: the control group, the NEC group, the NEC + intraperitoneal VEGF (50 ng/kg) group (NEC + VEGF IP group), and the NEC + oral VEGF (50 ng/kg) group (NEC + VEGF OR group). NEC was induced by lipopolysaccharide/hypoxia and cold stress. The animals were sacrificed 72 hours later. After laparotomy, we obtained a region of the proximal small bowel from the ileocecal valve about 18 cm in length. The NEC histological grade, apoptosis histological score, and caspase-3 activity were lower in the NEC + VEGF IP and OR groups than in the NEC group. In the NEC + VEGF IP and OR groups, the messenger RNA expression of apoptotic and inflammatory genes, such as Bax, NF-κB, p53, Fas, FasL, and PAF-R, but not that of Bcl-2, was decreased, as was the Bax/Bcl-2 protein ratio. Histological analysis revealed that the apoptosis-blocking effect of VEGF was more effective in the NEC + VEGF IP group than in the NEC + VEGF OR group. We identified apoptotic and inflammatory genes to confirm the preventive effect of VEGF pretreatment on NEC in rats. This study presents a novel approach to prevent apoptosis via VEGF pretreatment in rats with lipopolysaccharide/hypoxia-induced NEC.

Sodium butyrate aggravates glucose dysregulation and dyslipidemia in high fat-fed Wistar rats

Sodium butyrate (NaB), a short chain fatty acid (SCFA) has been shown to improve metabolic, glucose and lipid signaling. High fat diet elicits increased risk of cardiometabolic disease due to dysmetabolism, altered endothelial function and elevated oxidant activities. This study aims at evaluating the effect of NaB on high fat diet-fed female Wistar rats, and the possible role of vascular endothelial growth factor (VEGF). Twenty female Wistar rats with mean weight of 120 ± 5 g were divided randomly after one week of acclimatization into four groups: Control diet (CTR), High fat diet (HFD), NaB (200 mg/kg), and HFD + NaB. After six weeks of the experimental procedure, blood samples were collected by cardiac puncture. Data were analyzed and expressed in mean ± SEM and p-values <0.05 were accepted as significant. Data showed that HFD increased lactate dehydrogenase (LD) and free fatty acid (FFA), but not triglyceride (TG) and total cholesterol (TC). It also led to insulin resistance (elevated fasting blood glucose, insulin and homeostasis model assessment for insulin resistance). These effects of HFD were accompanied by increased lipid peroxidation (malondialdehyde and 4-hydroxynonenal). Sodium butyrate significantly decreased circulating nitric oxide (NO) and LD while increasing FFA, TG, insulin resistance, aggravated lipid peroxidation and increased VEGF in HFD rats (P < 0.05). We speculated therefore, that NaB aggravated glucose dysregulation and dyslipidemia, which is accompanied by increased VEGF.

Electroacupuncture attenuates ischemic injury after stroke and promotes angiogenesis via activation of EPO mediated Src and VEGF signaling pathways.

Although electroacupuncture (EA) has been shown to be effective in the treatment of stroke, its mechanisms of action remain undefined. This study explored the therapeutic effects of EA in rats with cerebral ischemia-reperfusion injury (CIRI) and evaluated its possible mechanisms in promoting angiogenesis. To evaluate the effect of EA, we used 2, 3, 5-Triphenyl-2H-Tetrazolium Chloride (TTC) staining and behavior score to calculate the cerebral infarct volume and neurological deficit score after CIRI. Western blot (WB) analysis was employed to evaluate the expression of cluster of differentiation 34 (CD34), erythropoietin (EPO), vascular endothelial growth factor (VEGF) and phospho-Src (p-Src) in the brain of the rats with CIRI. On the other hand, we established an oxygen-glucose deprivation/reoxygenation (OGD/R) injury model using brain microvascular endothelial cells (BMECs), and analyzed cell viability and expression of VEGF or p-Src using cell counting kit-8 (CCK-8) and WB, respectively. Our data showed that EA at the GV26 acupoint could significantly promote the expression of CD34, EPO, VEGF and p-Src in CIRI rats. Our CCK-8 results demonstrated that intervention with recombinant EPO and VEGF proteins remarkably improved the viability of BMECs after OGD/R, while a Src inhibitor, PP1, reversed this phenotype. The WB results showed that the recombinant EPO protein increased the expression of VEGF and p-Src, which was significantly inhibited by PP1. Taken together, our findings showed that EA at the GV26 acupoint can significantly attenuate ischemic injury after stroke and promote angiogenesis via activation of EPO-mediated Src and VEGF signaling pathways. Besides, the upregulation of VEGF may also be associated with the activation of Src by EPO.

The onset of age-related benign prostatic hyperplasia is concomitant with increased serum and prostatic expression of VEGF in rats: Potential role of VEGF as a marker for early prostatic alterations

The onset of age-related benign prostate hyperplasia (BPH) is linked with changes in the expression of specific prostatic chemokines. The aim of this work was to characterize those most relevant changes through the simultaneous analysis of 34 chemokines in both prostatic tissue and serum in rats at different ages with the aim to identify clinically workable parameters for the detection of early prostatic alterations. The study included 28 healthy Sprague-Dawley male rats that were distributed in four groups, 1 month-old (prepuberal; n = 7), 3 months-old (young; n = 7), 6 months-old (mature; n = 7) and 12 months-old (elder; n = 7). Chemokines were analyzed through a commercial mini-array system specially designed for rat tissues. Serum testosterone levels and prostatic histological status were also evaluated. Histological lesions indicative of BPH were detected in three mature rats and in all elder ones. Mini-arrays from prostatic tissue showed that young animals had an overall decreased expression of most of the analyzed chemokines when compared with prepuberal rats, with the exception of agrin, which showed a significant (P < 0.05) increase (100.0 ± 1.3, arbitrary units in prepuberal rats vs.148.2 ± 4.1, arbitrary units in young ones). Older animals showed further specific changes in 4 out 34 analyzed chemokines, namely agrin, platelet-derived growth factor (PDGF), tissue inhibitor of metalloproteinase-1 (TIMP-1) and vascular endothelial growth factor (VEGF). Additionally, elder rats showed the lowest intensity levels of agrin combined with the highest ones for PDGF, TIMP1 and VEGF when compared with all other groups. Finally, a significant increase of serum VEGF was detected in elder, BPH-affected rats when compared with young ones. Results indicated that the onset of both rat puberty and BPH would be related with specific changes in the prostatic expression of chemokines such as VEGF. Otherwise, the observed changes in serum VEGF levels could suggest the future possible utilization of serum VEGF levels to detect early pathological prostatic processes.

The effect of continuous aerobic exercise on serum angiogenic and angiostatic factors in induction model of acute myocardial infarction male rats with coronary artery disease

Background. Aerobic training somewhat corrects endothelial dysfunction in patients with coronary artery disease (CAD), but the most effective form of exercise is still unclear; therefore, the purpose of the present study was to investigate the effect of 8 weeks of continuous aerobic exercise on serum vascular endothelial growth factor (VEGF) as an angiogenic factor and endostatin (ES) as an angiostatic factor in male rats with coronary artery disease. Methods. The subjects of the present experimental study were 30 healthy male 2-months old Wistar rats divided into three groups: the experimental group, the control group with coronary artery disease, and the healthy control group. After rupturing 20 of the rats by isoproterenol, 10 rats in the experimental group performed eight weeks of continuous aerobic exercise on a treadmill, with an incremental intensity of 50% in the first session to 78% in the last session, whereas both control groups did not exercise. Seventy-two hours after the final training session, blood samples were taken for serum VEGF and ES indices, and one-way ANOVA with Scheffer posthoc tests was used to compare the mean of variables among the studied groups. Results. The results showed that discontinuous aerobic exercise could increase the blood VEGF in rats with coronary artery disease (P≤0.01), while there was no difference in the level of endostatin in the experimental group compared with control groups (P&gt;0.05). Conclusion. It seems that continuous aerobic exercises can be used in the rehabilitation of patients with coronary artery disease and might be effective in the process of angiogenesis.

Вміст факторів росту та фактора 1α, індукованого гіпоксією, в рановому ложі шкіри щурів різного віку

The aim of the study was to determine the content of vascular endothelial growth factor (VEGF), nerve growth factor (NGF) and hypoxia-inducible factor-1alpha (HIF- 1α) in the skin of 40 female rats of different ages (3 and 12 mo) after closure of the wound bed. In each age group composed of 20 rats, 10 rats served as a control group, and in remaining rats a facelift operation was performed and cut wounds on the anterior abdominal wall (5 cm × 0.5 cm) were simulated. The duration of wound surface healing in rats of different age groups was recorded. On the day of complete healing, the animals were killed, and the skin was cut in the areas of the former wound bed. In control rats, the skin was excised in the same places. The content of VEGF, NGF and HIF-1α was determined in the skin by enzyme- linked immunosorbent assay. It was found that in the group of young (3-month-old) rats, complete healing of the wound surface after facelift surgery occurred after 14.0 ± 1.0 days, and on the anterior abdominal wall - after 13.0 ± 1.0 days. In 12-month-old rats, the duration of wound surface healing after facelift surgery and incised wound on the anterior abdominal wall increased to 17.0 ± 1.5 days. In the former wound bed, the content of HIF-1α in young rats increased by 60.7%, and in 12-month-old rats - by 231.6%. In the former wound bed, the content of VEGF and NGF in young rats increased by 14.8 and 11.7%, respectively, and in 12-month-old rats - by 182.4 and 152.6%, respectively. It was concluded that more pronounced hypoxia in the skin after surgery in 12-month-old rats may be the cause of postoperative complications.

Prevention of lumbar disc degeneration through co-manipulation of insulin-like growth factor 1 and vascular endothelial growth factor

BackgroundAssociated with abnormal angiogenesis and disc dysfunction, lumbar disc degeneration (LDD) appears to be an important disease suffered by elderly people. Previous studies have highlighted the importance of insufficient insulin-like growth factor 1 (IGF1) and excessive vascular endothelial growth factor (VEGF) in the development and progression of LDD, though a practical therapeutic strategy is lacking.MethodsThe expression of IGF1 and VEGF was assessed in LDD specimens compared to normal disc tissue as a control. A gene therapy approach was performed, in which an adeno-associated virus (AAV) carrying both IGF1 and shVEGF (AAV-IGF1/shVEGF) was orthotopically injected to the rats that had undergone LDD. The alterations in IGF1 and VEGF levels in the treated disc tissue were confirmed by immunohistochemistry. The outcome of this therapy was assessed by disc cell death using an annexin V-FITC assay and by assessing lumbar proteoglycan and collagen II levels using ELISA.ResultsIGF1 expression was significantly downregulated in LDD, while VEGF expression was significantly upregulated in LDD, compared to normal controls. Combined AAV-IGF1/shVEGF treatment simultaneously corrected the insufficient IGF1 and the excessive VEGF in LDD rats. Moreover, AAV-IGF1/shVEGF significantly reduced disc cell death in the vertebral pulp and annulus fibrosus and significantly enhanced the lumbar proteoglycan and collagen II levels.ConclusionsThe simultaneous increase in IGF1 and depletion of VEGF effectively prevented the development of LDD, suggesting its potential as a novel therapeutic approach for LDD which is clinically translatable.

Effect of Exercise Preconditioning on Protein Expression of VEGF and NeuN in Rats with Cerebral Ischemia-reperfusion

Objective:To explore the effects of exercise preconditioning on the expression of vascular endothelial growth factor(VEGF)and neuronal core antigen(NeuN)proteins in rats with cerebral ischemia-reperfusion.Methods:The rats were randomly divided into sham-operation group,model group,exercise sham-operation group(exercise pretreatment and sham-operation group)and exercise model group(exercise pretreatment and model group)by the random number table method,with 24 rats in each group.Each group was then divided into two subgroups according to the cerebral ischemia-reperfusion time of 24 hours and 3 days,with 12 rats in each subgroup.Before the model was built,the exercise sham-operation group and the exercise model group were trained on the treadmill for 3 weeks.In the model group and exercise model group,the modified Longa suture method was used to prepare the rat middle cerebral artery occlusion(MCAO)model.After 2 hours,the suture was slowly pulled out to the branch of the common carotid artery.The method of modeling rats in the sham-operation group and the exercise sham-operation group was the same as the above,but the thread plug was only inserted about 10 mm from the common carotid artery and then pulled out,which could not block the middle cerebral artery blood supply.The modified neurologic severity score(mNSS)was used to assess neurological function,while the immunohistochemistry and Western blot were respectively used to determine the protein expression levels of VEGF and NeuN in the ischemic lateral brain tissue.Results:1)There were no neurological deficits in the sham-operation group and the exercise sham-operation group.Compared with the model group,the neurological deficit scores of the exercise model group at 24 hours and 3 days after cerebral ischemia-reperfusion decreased,and the comparison between the two groups was statistically significant(P<0.05).2)24 hours after cerebral ischemia-reperfusion,a small amount of VEGF expression were seen in the sham operation group,the positive cell bodies were small,and the protrusions were thin;compared with the positive rate of the exercise model group(14.40%),the positive rate of the sham-operation group(4.70%),the positive rate of the model group(9.80%),the positive rate of the exercise sham-operation group(8.80%)were low,and the differences were statistically significant respectively(P<0.05).Three days after cerebral ischemia-reperfusion,compared with the positive rate of the exercise model group(23.80%),the positive rate of the sham-operation group(5.40%),the positive rate of the model group(12.40%),and the positive rate of the exercise sham-operation group(14.20%)were all reduced,and the differences were statistically significant respectively(P<0.05).3)24 hours after cerebral ischemia-reperfusion,compared with the exercise model group,the expression of NeuN protein in the model group was less,and the difference was statistically significant(P<0.05);Three days after cerebral ischemia-reperfusion,compared with the exercise model group,the expression of the model group was less,and the difference was statistically significant(P<0.05).Conclusion:Exercise preconditioning before cerebral ischemia-reperfusion can reduce the performance of neurological deficits after cerebral ischemia-reperfusion,and improve sensorimotor dysfunction and motor behavior by enhancing the protein expression of VEGF and NeuN.

A Method of Manufacturing a Long-Acting Medicinal Film Containing VEGF

Background. The development of new methods for delivering biologically active substances to the surgical site is a promising area of modern surgery. One of the biologically active substances used to stimulate regeneration is the vascular endothelial growth factor (VEGF). The search for ways to gradually and over a long period of time deliver VEGF to the surgical site is a promising area of research. Aim. To develop a method for delivering VEGF to the surgical site and to assess its elimination in the early postoperative period. Materials and methods. The study included 78 male Wistar rats at the age of 10 months. All animals underwent reconstructive surgery on the trachea, the animals were divided into 3 groups: group 1 – without a medicinal film, group 2 – with a medicinal film of prolonged action, group 3 – with a medicinal film of prolonged action containing VEGF. Blood sampling was carried out on days 1, 3, and 21 of the study, using the method of enzyme-linked immunosorbent assay to determine the level of VEGF in blood plasma, the unit of measurement was pg/ml. Results . A long-acting medicinal film containing VEGF has been developed. It was revealed that the use of a medicinal film containing VEGF significantly increases the VEGF index in blood plasma by 26 times starting from the first day of the study and remained high throughout the study. Conclusion . The results obtained indicate the effectiveness of the developed medicinal film of prolonged action. Elimination of VEGF starts from the first day of the study and lasts up to 21 days. High VEGF indices, according to the authors, are associated with the exogenous introduction of VEGF into the animal organism in the form of a prolonged-action film and the induction of endogenous VEGF in rats.

Expression of syndecan-1, PKC and VEGF in rats with acute kidney injury and correlation between syndecan-1 and renal function.

This study was designed to investigate the expression of syndecan-1 (Sdc-1), protein kinase C (PKC) and vascular endothelial growth factor (VEGF) in rats with acute kidney injury, as well as the association between Sdc-1 and indicators [such as serum creatinine (Scr) and blood urea nitrogen (BUN)] related to renal function. A total of 120 clean grade 2-week-old SD rats were selected and randomized into experimental group and control group (n=60). At 12 h (T1), 24 h (T2), 36 h (T3), 48 h (T4) after the model was established, 3 mL blood from abdominal aorta was taken, and Sdc-1, PKC, VEGF, serum creatinine (Scr), urea nitrogen (BUN) and other indicators were detected by Enzyme-Linked Immunosorbent Assay (ELISA). The expression levels of Sdc-1, PKC and VEGF in the experimental group were increasing from T1 to T4, with statistically significant difference between every two time points (p<0.05); the expression levels of Scr and BUN in the experimental group was increasing from T1 to T4, with statistically significant difference between every two time points (p<0.05). The level of Sdc-1 in the serum of rats in the experimental group was positively correlated with Scr (r=0.668, p<0.001), negatively correlated with BUN (r=0.722, p<0.001), and positively correlated with BUN (r=0.722, p<0.001); PKC level was positively correlated with Scr (r=0.589, p<0.001), BUN (r=0.788, p<0.001), and VEGF level was positively correlated with Scr (r=0.666, p<0.001), BUN (r=0.784, p<0.001). As the concentration of syndecan-1 increases gradually, renal dysfunction aggravates accordingly, so syndecan-1 can be used as a marker of acute kidney injury and can be used to judge the degree of kidney injury at an early stage.

Effect of acupuncture technique of Tiaoxin Tongdu on learning-memory ability and expressions of hippocampal VEGF and Ang-1 in rats with vascular dementia

To observe the effect of acupuncture technique of Tiaoxin Tongdu on learning-memory ability and expressions of hippocampal vascular endothelial growth factor (VEGF) and angiogenin-1 (Ang-1) in rats with vascular dementia (VD), and to explore the mechanism of acupuncture technique of Tiaoxin Tongdu for VD. A total of 24 male SD rats were randomly divided into a sham operation group, a model group, a medication group and an acupuncture group after Morris water maze test, 6 rats in each group. VD model was established by permanent ligation of bilateral common carotid arteries in the model group, the medication group and the acupuncture group. Treatment was given on the next day after successful modeling. The rats in the acupuncture group were treated with acupuncture at "Baihui" (GV 20), "Shenting" (GV 24), "Shuigou" (GV 26), "Dazhui" (GV 14), "Fengfu" (GV 16), "Mingmen" (GV 4), "Neiguan" (PC 6), "Daling" (PC 7) and "Laogong" (PC 8) for 30 min; the rats in the medication group were treated with nimodipine solution (0.0625 g/kg) by gavage, once a day, for 2 weeks. Morris water maze test was used to detect the behavior of rats before modeling, 2 weeks after modeling and after intervention; after intervention, the expressions of VEGF and Ang-1 protein in hippocampus were detected by Western blot. Compared with the sham operation group, the average escape latency of rats in the model group was prolonged (P<0.01), and the times of crossing the original platform were reduced (P<0.01). Compared with the model group, the average escape latency of rats in the medication group and acupuncture group was significantly shortened (P<0.01), and the times of crossing the original platform were increased (P<0.01, P<0.05). Compared with the sham operation group, the expressions of VEGF and Ang-1 protein in hippocampus in the model group were increased (P<0.05, P<0.01). Compared with the model group, the expressions of VEGF and Ang-1 protein in the hippocampus in the medication group and acupuncture group were significantly increased (P<0.01, P<0.05). The acupuncture technique of Tiaoxin Tongdu can significantly improve the learning and memory ability of VD rats, and its mechanism may be related to up-regulating the expressions of VEGF and Ang-1 protein in hippocampus and inducing angiogenesis.

Hypertonic saline mediates the NLRP3/IL-1β signaling axis in microglia to alleviate ischemic blood-brain barrier permeability by downregulating astrocyte-derived VEGF in rats.

IntroductionThe aim of this study was to explore whether the antibrain edema of hypertonic saline (HS) is associated with alleviating ischemic blood‐brain barrier (BBB) permeability by downregulating astrocyte‐derived vascular endothelial growth factor (VEGF), which is mediated by microglia‐derived NOD‐like receptor protein 3 (NLRP3) inflammasome.MethodsThe infarct volume and BBB permeability were detected. The protein expression level of VEGF in astrocytes in a transient focal brain ischemia model of rats was evaluated after 10% HS treatment. Changes in the NLRP3 inflammasome, IL‐1β protein expression, and the interleukin‐1 receptor (IL1R1)/pNF‐кBp65/VEGF signaling pathway were determined in astrocytes.ResultsHS alleviated the BBB permeability, reduced the infarct volume, and downregulated the expression of VEGF in astrocytes. HS downregulates IL‐1β expression by inhibiting the activation of the NLRP3 inflammasome in microglia and then downregulates VEGF expression by inhibiting the phosphorylation of NF‐кBp65 mediated by IL‐1β in astrocytes.ConclusionsHS alleviated the BBB permeability, reduced the infarct volume, and downregulated the expression of VEGF in astrocytes. HS downregulated IL‐1β expression via inhibiting the activation of the NLRP3 inflammasome in microglia and then downregulated VEGF expression through inhibiting the phosphorylation of NF‐кBp65 mediated by IL‐1β in astrocytes.

Metformin exerts renoprotective effect by reducing proteinuria in spontaneously-hypertensive rats

Purpose: To study the mechanism involved in metformin (DMBG)-induced reduction of albuminuria in spontaneously-hypertensive rats (SHRs).&#x0D; Methods: The SHRs were divided into DMBG SHR group (n = 30) given DMBG (300 mg/kg) and NC SHR group (n = 10) given distilled water (2 ml/day), while Wistar-Kyoto rats (WKY) rats were divided into DMBG WKY group (n = 30) given DMBG (300 mg/kg ) and NC WKY group (n = 10) administered distilled water (2 ml/day). Urinary protein levels were measured and compared. Inflammatory infiltration in renal tissue, and expression of vascular endothelial growth factor (VEGF) were assessed. Abdominal aortic blood was used to measure serum levels of creatinine and blood urea nitrogen (BUN).&#x0D; Results: Urinary protein was markedly elevated in SHRs, while BUN in SHRs was lowered, relative to WKY rats (p &lt; 0.05). Moreover, inflammatory cell population was lower in DMBG SHRs group than in WKY rats (p &lt; 0.05). Kidney expressions of VEGF in SHR and WKY rats treated with metformin were significantly reduced, relative to those in untreated rats, but VEGF-A in DMBG SHR rats was markedly elevated, relative to NC SHR group, and was also raised in DMBG WKY, when compared with NC WKY rats (p &lt; 0.05).&#x0D; Conclusion: Metformin reduces albuminemia in spontaneously hypertensive rats by up-regulating VEGF expression, thereby exerting renoprotective effect. This finding provides ideas for research and development of other therapeutic approaches.&#x0D; Keywords: Metformin, Spontaneous hypertension, Renoprotective, Albuminuria, Kidney, Vascular endothelial growth factor (VEGF)

β-hydroxybutyrate antagonizes aortic endothelial injury by promoting generation of VEGF in diabetic rats

Endothelial injury is regarded as the initial pathological process in diabetic vascular diseases, but effective therapy has not yet been identified. Although β-hydroxybutyrate plays various protective roles in the cardiovascular system, its ability to antagonize diabetic endothelial injury is unclear. β-hydroxybutyrate reportedly causes histone H3K9 β-hydroxybutyrylation (H3K9bhb), which activates gene expression; however, there has been no report regarding the role of H3K9bhb in up-regulation of vascular endothelial growth factor (VEGF), a crucial factor in endothelial integrity and function. Here, male Sprague-Dawley rats were intraperitoneally injected with streptozotocin to induce diabetes, and then treated with different concentrations of β-hydroxybutyrate. After 10 weeks, body weight, blood glucose, morphological changes and serum nitric oxide concentration were examined. Moreover, the mRNA expression level, protein content and distribution of VEGF in the aorta were investigated, as were total protein β-hydroxybutyrylation and H3K9bhb contents. The results showed injury of aortic endothelium, along with reductions of the concentration of nitric oxide and generation of VEGF in diabetic rats. However, β-hydroxybutyrate treatment attenuated diabetic injury of the endothelium and up-regulated the generation of VEGF. Furthermore, β-hydroxybutyrate treatment caused marked total protein β-hydroxybutyrylation and significant elevation of H3K9bhb content in the aorta of diabetic rats. The ability of β-hydroxybutyrate to protect against diabetic injury of the aortic endothelium was greatest for its intermediate concentration. In conclusion, moderately elevated β-hydroxybutyrate could antagonize aortic endothelial injury, potentially by causing H3K9bhb to promote generation of VEGF in diabetic rats.

HMGB1 Protects the Heart Against Ischemia-Reperfusion Injury via PI3K/AkT Pathway-Mediated Upregulation of VEGF Expression.

Delivery of exogenous high mobility group box 1 (HMGB1) may exert a beneficial effect on myocardial ischemia–reperfusion (I/R) injury. Since the expression of vascular endothelial growth factor (VEGF) and phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) in the myocardium mediates the cardioprotective function of basic fibroblast growth factor, we hypothesized that VEGF and the PI3K/Akt signaling pathway also mediate the protective effects of intravenously delivered HMGB1. Thus, the objective of the present study was to analyze the impact of intravenous administration of HMGB1 on the myocardial expression of VEGF, myocardial fibrosis, and cardiac function in rats subjected to acute myocardial I/R. The ischemia was induced by ligation of the left anterior descending coronary artery for 30 min and was followed by 3 h of reperfusion. Myocardial malondialdehyde content, infarct size, and collagen volume fraction decreased, while the activity of superoxide dismutase was increased, the expression of VEGF and p-Akt was upregulated, and cardiac function was improved in the HMGB1-treated group when compared with rats subjected to I/R only (all P < 0.05). However, these effects of HMGB1 were abolished by LY294002. The obtained results demonstrate that the cardioprotective effects of intravenous administration of HMGB1 prior to I/R may be mediated by upregulation of myocardial expression of VEGF, which may activate the PI3K/Akt signaling pathway.

COX-2/PGE2 facilitates fracture healing by activating the Wnt/β-catenin signaling pathway.

The aim of this study was to explore the influence of cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) on fracture healing by activating the Wnt/β-catenin signaling pathway. In this study, 36 adult Sprague-Dawley (SD) rats raised in our laboratory were selected as research objects. The rats were subjected to fracture surgery on the middle part of the right femoral shaft. Subsequently, they were randomly divided into the control group and experimental groups (including experimental group A and experimental group B). Rats in experimental group A were injected with PGE 2 or COX-2 selective inhibitor NS-398, while rats in experimental group B were injected with PGE2 (5 μmol/L). Meanwhile, rats in the control group were injected with the same amount of normal saline. After that, the transcriptional levels of PEG2, COX-2, vascular endothelial growth factor (VEGF) and β-catenin in rats of the experimental group A, experimental group B and control group were detected via fluorescence quantitative Polymerase Chain Reaction (PCR) assay. Enzyme-linked immunosorbent assay (ELISA) and Western blotting were conducted to determine the changes in protein levels of PEG2, COX-2, VEGF and β-catenin in rats of the experimental group A, experimental group B and control group. The expression level of VEGF in bone tissues at fracture ends of rats in the experimental group A, experimental group B and control group was observed through the hematoxylin-eosin (HE) staining. Furthermore, micro-computed tomography (CT) was employed to evaluate callus formation. The transcriptional and translational levels of COX-2, β-catenin and VEGF in rats of experimental group A treated with COX-2 inhibitors were significantly down-regulated when compared with those of the control group, showing statistically significant differences (p<0.05). However, the levels of these genes were markedly elevated in the experimental group B treated with PGE2 in comparison with those in the control group, and the differences were statistically significant (p<0.05). After 6 weeks, HE staining showed that the expression level of VEGF in rats of the experimental group B was remarkably higher than that of the experimental group A (p<0.05). Micro-CT results revealed that the mean trabecular plate density (MTPD) of rats in the experimental group B (73.29±5.4) was markedly higher than the number of osteoblasts (49.6±3.9) in the experimental group A, showing a statistically significant difference (p<0.05). COX-2/PGE2 facilitates fracture healing by activating the Wnt/β-catenin signaling pathway.

Correlation between endometrial receptivity with expressions of IL-1 and VEGF in rats with polycystic ovary syndrome.

To investigate the correlation between endometrial receptivity with expressions of interleukin-1 (IL-1) and vascular endothelial growth factor (VEGF) in rats with polycystic ovary syndrome (PCOS). A total of 24 female Sprague-Dawley (SD) 21 days old were randomly divided into control group (n=12) and PCOS group (n=12). Rats in the control group were normally raised, and PCOS model was established in rats of the PCOS group. All the rats were sacrificed when they grew to 80 days old. Immunohistochemistry was applied to detect the expressions of IL-1 and VEGF. Western blotting was performed to measure the relative expressions of IL-1 and VEGF proteins. Quantitative Polymerase Chain Reaction (qPCR) was utilized to determine the relative messenger ribonucleic acid (mRNA) expressions of IL-1 and VEGF. Data related to endometrial receptivity were detected. The expression levels of IL-1 and VEGF in the PCOS group declined markedly compared with those in the control group, and the differences were statistically significant (p<0.05). PCOS group had notably lower protein expressions of IL-1 and VEGF than the control group, with statistically significant differences (p<0.05). The mRNA expressions of IL-1 and VEGF in PCOS group were significantly lower than those in the control group, displaying statistically significant differences (p<0.05). Compared with that in the control group, the endometrial receptivity of rats in the PCOS group was reduced evidently, and the difference was statistically significant (p<0.05). Both IL-1 and VEGF had positive correlations with the endometrial receptivity. Both IL-1 and VEGF are positively correlated with the endometrial receptivity in the case of PCOS, which can serve as therapeutic targets for PCOS and improve endometrial receptivity in the future.

Inhibitory effect of ginsenoside Rg3 on vascular growth and expression of vascular endothelial growth factor and matrix metalloproteinase-9 in breast cancer rats

Objective To explore the inhibitory effect of ginsenoside Rg3 on vascular growth and expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP)-9 in breast cancer rats. Methods The rat model of breast cancer was replicated. The successful rats were divided into model group, low dose group and high dose group according to the random number table method, 20 rats in each group, and 20 healthy rats were taken as blank control group. Rats in the blank control group and model group were given 0.5% sodium carboxymethyl cellulose solution by gavage, while those in the low-dose group and the high-dose group were given 0.5% sodium carboxymethyl cellulose solution containing ginsenoside Rg3. The volume, mass, tumor inhibition rate, microvessel density (MVD), expression of VEGF and MMP-9 were measured, and the serum levels of VEGF and MMP-9 were measured.Statisticalanalysis of data using the statistical product and service solutions 19.0 software. Results The tumor volume of model group, low dose group and high dose group were (4.83±0.66), (3.48±0.51), (1.58±0.23) cm3, and the mass of tumors were (5.17±0.59), (4.00±0.42), (2.09±0.26) g, respectively. The inhibition rates were 0.00%, 22.43%, 53.81%, respectively. The volume and mass of tumors in the low dose group and the high dose group were significantly smaller than those in the model group ( t=7.238, 20.795, 7.225, 21.364, P<0.05), the volume and mass of tumors in the high dose group were significantly smaller than those in the low dose group (t=15.188, 17.292, P<0.05), and the inhibition rate in the high dose group was significantly higher than that in the low dose group (X2=12.324, P<0.05). The MVDs in tumors and breast tissues of rats in blank control group, model group, low dose group and high dose group were (7.53±1.53), (23.52±4.21), (17.32±3.52) and (12.20±2.19), respectively. The serum levels of VEGF were (218.42±46.37), (435.67±83.21), (350.13±45.26), (278.58±30.56) mg/L, and the serum levels of MMP-9 were (230.52±32.56), (460.22±60.36), (330.73±51.57), (255.72±41.73) mg/L. The expression levels of VEGF protein in tissues were (0.23±0.09), (0.58±0.14), (0.46±0.12), (0.25±0.09). The expression levels of MMP-9 protein in tissues were (0.14±0.11), (0.82±0.22), (0.63±0.19), (0.46±0.20), respectively. MVD, VEGF and MMP-9 in the model group were significantly higher than those in the blank control group (t= 15.964, 9.405, 12.364P<0.05). MVD, VEGF and MMP-9 in the low-dose group and the high-dose group were significantly lower than those in the model group (t=5.053, 10.668, 2.910, 8.867, 2.923, 5.415, P<0.05). MVD, VEGF and MM-9 in the high-dose group were significantly lower than those in the low-dose group (t=5.523, 6.261, 2.755P<0.05). Serum levels of VEGF and MMP-9 in model group were significantly higher than those in blank control group (t=10.199, 14.978, P<0.05). Serum levels of VEGF and MMP-9 in low-dose group and high-dose group were significantly lower than those in model group (t=4.039, 7.925, 7.294, 12.463, P<0.05). Serum levels of VEGF and MMP-9 in high-dose group were significantly lower than those in low-dose group (t=5.859, 5.057, P<0.05). Conclusion Ginsenoside Rg3 can inhibit the growth of blood vessels and the expression of VEGF and MMP-9 in breast cancer model rats. Key words: Ginsenoside Rg3; Breast cancer; Rat; Vascular growth; Vascular endothelial growth factor; Matrix metalloproteinase-9