Mechanism of Tongmai Yangxin pill to reduce the no-reflow after myocardial ischemia and reperfusion by activating HIF-1α/eNOS signaling pathway up-regulated by GPER / 药学学报

The Tongmai Yangxin pill (TMYX) has potential clinical effects on no-reflow (NR); however, the effective substances and mechanisms by which this occurs remain unclear. This study evaluates the cardioprotective effects and molecular mechanisms of TMYX against NR. We used a myocardial NR rat model (2 h after myocardial ischemia and 2 h after reperfusion) to confirm the effect and mechanism of action of TMYX in alleviating NR. In vitro studies in isolated coronary microvasculature of NR rats and in silico network pharmacology analyses were performed to reveal the underlying mechanisms of TMYX and determine the main components, targets, and pathways of TMYX, respectively. The experiment was approved by the Ethics Committee of Hunan University of Chinese Medicine (LLBH-202212160001). TMYX showed therapeutic effects on NR by improving cardiac structure and function, reducing NR, ischemic areas, and cardiomyocyte injury, and decreasing the content of cardiac troponin I (cTnI). Moreover, the mechanism of TMYX predicted by network pharmacology is related to the hypoxia inducible factor-1 (HIF-1), nuclear factor kappa-B (NF-κB), and tumor necrosis factor (TNF) signaling pathways. TMYX increased the expression of G protein-coupled estrogen receptor (GPER), phospho-extracellular signal-regulated kinase (p-ERK), and HIF-1α. In vitro, TMYX enhanced the diastolic function of coronary microvascular cells; however, this effect was inhibited by GPER inhibitor (G-15), eNOS inhibitor (L-NAME), and sGC inhibitor (ODQ). This study integrates pharmacology and experimental evaluation to reveal that TMYX activates HIF-1α/eNOS signaling pathway by upregulating GPER to relax coronary microvessels, thereby significantly alleviating NR.

The effect and mechanism of formononetin on alleviating no-reflow after myocardial ischemia and reperfusion by up-regulating the PI3K/Akt/eNOS signal pathway activated by GPER / 药学学报

To investigate the cardioprotective effect of formononetin (FMN) on no-reflow (NR) after myocardial ischemia-reperfusion and its molecular mechanism based on integrated pharmacology and experimental verification, firstly, human breast cancer MCF-7 cells and myocardial NR rats were used to confirm the estrogenic activity and the effect of alleviating NR of FMN, respectively. Male SD rats were divided into Sham, NR, FMN (20 mg·kg-1) and sodium nitroprusside (SNP, 5.0 mg·kg-1) groups, which were administered once a day for one week, the experiment was approved by the Ethics Committee of Tianjin University of Traditional Chinese Medicine (TCM-LAEC2019095). The pharmacological analysis and in vivo study of NR rats were integrated to reveal the mechanism of FMN improving NR. The results showed that FMN had estrogenic effect and reduced NR by improving cardiac structure and function, reducing NR, ischemic myocardial area and pathological injury of cardiomyocytes. Integrated pharmacology predicts that the mechanism of FMN improving NR is mainly related to phosphatidyinositol-3-kinase-protein kinase B (PI3K-Akt) signal pathway. Phytoestrogens play a role in cardiovascular protection mainly by activating G protein-coupled estrogen receptor (GPER). GPER is also an important regulator in the upstream of PI3K-Akt signaling pathway. This study found that FMN can significantly activate GPER, p-PI3K, p-Akt and phospho-endothelial nitric oxide synthase (p-eNOS). It has good binding ability with GPER and eNOS protein. In this study, through the integration of pharmacology and experimental evaluation, it is revealed that FMN activates PI3K/Akt/eNOS signal pathway by activating GPER, thus significantly improving NR.

Copper induces damage, oxidative stress and cell death in endothelium of chronic intoxicated Wistar rats / El cobre induce daño, estrés oxidativo y muerte celular en el endotelio de ratas Wistar intoxicadas

SUMMARY: Reactive Oxygen Species (ROS) are part of the functional balance of various systems, they can generate cellular damage by oxidative stress associated with disease processes such as atherosclerosis, cardiovascular disease, diabetes, and aging. Some studies report that copper induces damage to the endothelium, which could be associated with cardiovascular pathologies. This study was an experimental comparative, prospective, longitudinal, and controlled clinical trial in a murine animal model. Twenty-four male Wistar rats were included, the distribution of the groups was time-depending chronic exposition to copper, and a control group. Results show gradual alterations in the groups treated with copper: areas with loss of the endothelium, signs of disorganization of smooth muscle fibers in the tunica media, as well as areas with the fragmentation of the elastic sheets. A significant statistical difference was observed in the active- Caspase-3 analysis expression in the aortic endothelium and endothelium of the capillaries and arterioles of the lung between the control group vs 300 ppm of copper. Expression of eNOS was detected in the endothelium of the aorta and vessels of the lung. Our study shows histological changes in the walls of the great vessels of intoxicated rats with copper, and the increment of inflammatory cells in the alveoli of the study model, mainly at a high dose of copper exposition. These results will be useful to understand more about the mediators involved in the effect of copper over endothelium and cardiovascular diseases in chronic intoxication in humans.

RESUMEN: Las Especies Reactivas de Oxígeno (ROS) son parte del equilibrio funcional de varios sistemas, pueden generar daño celular por estrés oxidativo asociado a procesos patológicos como aterosclerosis, enfermedades cardiovasculares, diabetes y envejecimiento. Algunos estudios informan que el cobre induce daños en el endotelio, lo que podría estar asociado a patologías cardiovasculares. Este estudio fue un ensayo clínico experimental comparativo, prospectivo, longitudinal y controlado en un modelo animal murino. Se incluyeron veinticuatro ratas Wistar macho, la distribución de los grupos fue la exposición crónica al cobre en función del tiempo y un grupo de control. Los resultados muestran alteraciones graduales en los grupos tratados con cobre: áreas con pérdida del endotelio, signos de desorganización de las fibras musculares lisas en la túnica media, así como áreas con la fragmentación de las láminas elásticas. Se observó una diferencia estadística significativa en la expresión del análisis de caspasa-3 activa en el endotelio aórtico y el endotelio de los capilares y arteriolas del pulmón entre el grupo de control frente a 300 ppm de cobre. Se detectó expresión de eNOS en el endotelio de la aorta y los vasos del pulmón. Nuestro estudio muestra cambios histológicos en las paredes de los grandes vasos de ratas intoxicadas con cobre, y el incremento de células inflamatorias en los alvéolos del modelo de estudio, principalmente a una alta dosis de exposición de cobre. Estos resultados serán útiles para comprender más sobre los mediadores involucrados en el efecto del cobre sobre el endotelio y las enfermedades cardiovasculares en la intoxicación crónica en humanos.

Upregulation of ppET-1/ETBR/eNOS mRNA Expression After Calcitriol Treatment in Chronic Kidney Diseases Model in Rats

@#Introduction: Myofibroblast formation in the interstitial area is the hallmark of chronic kidney disease (CKD). Endothelin signalling has been known to play role in physiology and pathophysiology in the kidney. Vitamin D has a reno-protective effect through inhibiting inflammation and fibrosis. However, the interaction between vitamin D and endothelin signalling in the CKD model has not been elucidated yet. Therefore, we aimed to check the difference impact of endothelin (ET) receptor in CKD. Methods: Sprague Dawley rats (3-months-old, 150-250grams) underwent 5/6 subtotal nephrectomy (SN) to induce CKD. Then, it was divided into 4 groups (each contains 6 rats): sham operation (SO), 5/6 subtotal nephrectomy (SN), calcitriol groups (0.01µg/100grBW/day (SN-D1), and 0.05µg/100grBW/day (SN-D2). Calcitriol was administered for 14 days after the surgery. The Sham Operation (SO) group was injected with NaCl. At the specified date, the rats were sacrificed and the kidneys were harvested. Fibrosis was quantified based on Sirius Red staining. Immunostaining was done for localizing fibroblast (PDGFRβ). The mRNA expressions of prepro-ET-1, endothelin receptor A (ETAR), endothelin receptor B (ETBR), and endothelial nitrite oxide synthase (eNOS) were quantified using reverse-transcriptase PCR (RT-PCR). Results: The CKD promotes an elevation of prepro-ET-1, ETBR, and eNOS, and reduction of ETAR (p<0.05) mRNA expression compared to the SO group. Administration of calcitriol (SN-D1 and SN-D2) showed the vice versa effects. However, only SN-D2 group consistently showed statistically significant differences whenever compared to either SO or SN groups. Conclusion: Calcitriol might attenuate interstitial fibrosis in CKD model via ET-1/eNOS signalling.

Protective effect of tert-butylhydroquinone on retinal morphology and function in early diabetic rats and its mechanism / 中华实验眼科杂志

Objective:To investigate the protective effects of an antioxidant tert-butylhydroquinone (tBHQ) on the morphology and function of retina in early-stage experimental diabetic rats, and to explore the mechanism of its protective effect.Methods:Forty-five healthy SD rats of clean degree were randomized into normal control group, diabetes model group and tBHQ intervention group, with 15 rats in each group according to a random number table.The diabetes model was established via a single intraperitoneal injection of streptozotocin (STZ) in diabetes model group and tBHQ intervention group.Normal control group was intraperitoneally administered with an equal-volume injection of sodium citrate buffer.Rats in the tBHQ intervention group maintained a diet with 1% tBHQ for 2 weeks before the STZ injection, and the other two groups were fed with normal rat food only.Blood from tail vein was collected to assay the blood glucose level at 72 hours, 2 weeks and 4 weeks following modeling.Rat electroretinogram (ERG) was detected at 4 weeks after modeling.Morphological changes of rat retina were observed by hematoxylin and eosin staining.The apoptosis of retinal cells in different layers was detected by TUNEL assay.The expression of protein kinase B (Akt), p-Akt, endothelial nitric oxide synthase (eNOS) and p-eNOS was detected by Western blot.Müller cell line rMC-1 cells cultured in vitro were divided into 5 groups, including normal control group (72-hour culturing in normal medium), mannitol control group (72-hour culturing in medium containing 5.5 mmol/L glucose and 24.5 mmol/L mannitol), high glucose group (72-hour culturing in high-glucose medium), tBHQ intervention group (24-hour culturing in normal-glucose medium containing 5 μmol/L tBHQ, 72-hour culturing in high-glucose medium containing 5 μmol/L tBHQ), and phosphoinositide 3-kinase (PI3K) inhibitor group (6-hour culturing in normal medium containing 5 μmol/L LY294002, 24-hour culturing in normal-glucose medium containing 5 μmol/L LY294002 and 5 μmol/L tBHQ, 72-hour culturing in high-glucose medium containing 5 μmol/L LY294002 and 5 μmol/L tBHQ). The expression of Akt, p-Akt, eNOS and p-eNOS in the cells was detected by western blot.The use and care of animals complied with Regulations for the Administration of Laboratory Animals in Southwest Medical University.The study protocol was approved by the Animal Ethics Committee of Southwest Medical University (No.201711189). Results:The blood glucose level at 72 hours, 2 weeks and 4 weeks after modeling was higher in diabetic model group than tBHQ intervention group and normal control group (all at P<0.01). Four weeks after modeling, the scotopic ERG a-wave and b-wave amplitudes of diabetic model group were lower than those of normal control group and tBHQ intervention group (all at P<0.05). With edema and thickening of inner plexiform layer, thinning of inner nuclear layer and outer nuclear layer, as well as loosely arrangement and disorder of retinal layers, the number of retinal ganglion cells was decreased in diabetic model group in comparison with normal control group, all of which were improved in tBHQ intervention group in comparison with diabetic model group.There were more apoptotic retinal cells in diabetic model group than normal control group and tBHQ intervention group (both at P<0.05), which mainly existed in the outer nuclear layer.The relative expressions of p-Akt/Akt and p-eNOS/eNOS in rat retina of normal control group, diabetic model group and tBHQ intervention group were 0.76±0.11 and 0.83±0.06, 0.52±0.10 and 0.52±0.08, 1.14±0.31 and 1.03±0.13, respectively.The relative expressions of p-Akt/Akt and p-eNOS/eNOS in diabetic model group were lower than those of normal control group and tBHQ intervention group (all at P<0.01). The relative expressions of p-Akt/Akt and p-eNOS/eNOS in normal glucose group, mannitol control group, high glucose group, tBHQ intervention group and PI3K inhibitor group were 0.95±0.38 and 0.86±0.11, 0.94±0.27 and 0.74±0.29, 0.33±0.25 and 0.45±0.29, 1.32±0.37 and 1.28±0.22, 0.24±0.09 and 0.73±0.29, respectively.The relative expressions of p-Akt/Akt and p-eNOS/eNOS were significantly lower in high glucose group than those in normal glucose group and tBHQ intervention group (all at P<0.05), which were significantly lower in PI3K inhibitor group compared with tBHQ intervention group (both at P<0.01). Conclusions:tBHQ has protective effects on the morphology and function of retina in early diabetic rats, and the mechanism may be related to the activation of Akt/eNOS signaling pathway.

Tanshinone IIA alleviates monocrotaline-induced pulmonary hypertension in rats through the PI3K/Akt-eNOS signaling pathway / 南方医科大学学报

OBJECTIVE@#To explore the therapeutic mechanism of tanshinone IIA in the treatment of pulmonary arterial hypertension (PAH) in rats.@*METHODS@#A total of 100 male SD rats were randomized into 5 groups (n=20), and except for those in the control group with saline injection, all the rats were injected with monocrotaline (MCT) on the back of the neck to establish models of pulmonary hypertension. Two weeks after the injection, the rat models received intraperitoneal injections of tanshinone IIA (10 mg/kg), phosphatidylinositol 3 kinase (PI3K) inhibitor (1 mg/kg), both tanshinone IIA and PI3K inhibitor, or saline (model group) on a daily basis. After 2 weeks of treatment, HE staining and α-SMA immunofluorescence staining were used to evaluate the morphology of the pulmonary vessels of the rats. The phosphorylation levels of PI3K, protein kinase B (PKB/Akt) and endothelial nitric oxide synthase (eNOS) in the lung tissue were determined with Western blotting; the levels of eNOS and NO were measured using enzyme-linked immunosorbent assay (ELISA).@*RESULTS@#The results of HE staining and α-SMA immunofluorescence staining showed that tanshinone IIA effectively inhibited MCT-induced pulmonary artery intimamedia thickening and muscularization of the pulmonary arterioles (P < 0.01). The results of Western blotting showed that treatment with tanshinone IIA significantly increased the phosphorylation levels of PI3K, Akt and eNOS proteins in the lung tissue of PAH rats; ELISA results showed that the levels of eNOS and NO were significantly decreased in the rat models after tanshinone IIA treatment (P < 0.01).@*CONCLUSION@#Treatment with tanshinone IIA can improve MCT-induced pulmonary hypertension in rats through the PI3K/Akt-eNOS signaling pathway.

Influence of electroacupuncture on ghrelin and the phosphoinositide 3-kinase/protein kinase B/endothelial nitric oxide synthase signaling pathway in spontaneously hypertensive rats / 中西医结合学报

OBJECTIVE@#To investigate the influence of electroacupuncture (EA) on ghrelin and the phosphoinositide 3-kinase/protein kinase B/endothelial nitric oxide synthase (PI3K/Akt/eNOS) signaling pathway in spontaneously hypertensive rats (SHRs).@*METHODS@#Eight Wistar-Kyoto rats were used as the healthy blood pressure (BP) control (normal group), and 32 SHRs were randomized into model group, EA group, EA plus ghrelin group (EA + G group), and EA plus PF04628935 group (a potent ghrelin receptor blocker; EA + P group) using a random number table. Rats in the normal group and model group did not receive treatment, but were immobilized for 20 min per day, 5 times a week, for 4 continuous weeks. SHRs in the EA group, EA + G group and EA + P group were immobilized and given EA treatment in 20 min sessions, 5 times per week, for 4 weeks. Additionally, 1 h before EA, SHRs in the EA + G group and EA + P group were intraperitoneally injected with ghrelin or PF04628935, respectively, for 4 weeks. The tail-cuff method was used to measure BP. After the 4-week intervention, the rats were sacrificed by cervical dislocation, and pathological morphology of the abdominal aorta was observed using hematoxylin-eosin (HE) staining. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of ghrelin, nitric oxide (NO), endothelin-1 (ET-1) and thromboxane A2 (TXA2) in the serum. Isolated thoracic aortic ring experiment was performed to evaluate vasorelaxation. Western blot was used to measure the expression of PI3K, Akt, phosphorylated Akt (p-Akt) and eNOS proteins in the abdominal aorta. Further, quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to measure the relative levels of mRNA expression for PI3K, Akt and eNOS in the abdominal aorta.@*RESULTS@#EA significantly reduced the systolic BP (SBP) and diastolic BP (DBP) (P < 0.05). HE staining showed that EA improved the morphology of the vascular endothelium to some extent. Results of ELISA indicated that higher concentrations of ghrelin and NO, and lower concentrations of ET-1 and TXA2 were presented in the EA group (P < 0.05). The isolated thoracic aortic ring experiment demonstrated that the vasodilation capacity of the thoracic aorta increased in the EA group. Results of Western blot and qRT-PCR showed that EA increased the abundance of PI3K, p-Akt/Akt and eNOS proteins, as well as expression levels of PI3K, Akt and eNOS mRNAs (P < 0.05). In the EA + G group, SBP and DBP decreased (P < 0.05), ghrelin concentrations increased (P < 0.05), and the concentrations of ET-1 and TXA2 decreased (P < 0.05), relative to the EA group. In addition, the levels of PI3K and eNOS proteins, the p-Akt/Akt ratio, and the expression of PI3K, Akt and eNOS mRNAs increased significantly in the EA + G group (P < 0.05), while PF04628935 reversed these effects.@*CONCLUSION@#EA effectively reduced BP and protected the vascular endothelium, and these effects may be linked to promoting the release of ghrelin and activation of the PI3K/Akt/eNOS signaling pathway.

Involvement of ET-1/eNOS in the ameliorating effect of electroacupuncture on cardiac dysfunction in rats with spontaneously hypertensive / 中国针灸

OBJECTIVE@#To observe the effect of electroacupuncture (EA) at "Neiguan" (PC 6) on cardiac function of ventriculus sinister in rats with spontaneously hypertensive (SHR), and to explore the mediation effect of endothelin-1 (ET-1)/endothelial nitric oxide synthase (eNOS).@*METHODS@#Six 12-week-old male Wistar Kyoto (WKY) rats were taken as the normal group. Eighteen 12-week-old SHR were randomly divided into a model group, an EA group and a sham EA group, 6 rats in each group. The rats in the EA group were treated with EA (disperse-dense wave, 2 Hz/15 Hz in frequency, 1 mA in current intensity) at "Neiguan" (PC 6), 30 min each time, once a day for 8 weeks. The rats in the sham EA group were treated with superficial needling at "Neiguan" (PC 6) with no electrical stimulation applied. After treatment, the left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) were tested by echocardiographic analysis. The left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), heart rate (HR), the maximum rate of increase/decrease of left ventricular pressure (±dp/dtmax) were detected. The serum content of ET-1 was detected by ELISA. Western blot was used to evaluate the expression of ETAR, eNOS in myocardial tissue of left ventricular.@*RESULTS@#Compared with the normal group, LVEF, LVFS, +dp/dtmax/LVSP and -dp/dtmax/LVSP were decreased (P<0.01, P<0.05), while LVSP, LVEDP, +dp/dtmax and -dp/dtmax were increased (P<0.01) in the model group. Compared with the model group, LVEF, LVFS, +dp/dtmax/LVSP and -dp/dtmax/LVSP were increased (P<0.01, P<0.05), and LVSP and LVEDP were decreased (P<0.01) in the EA group. Compared with the normal group, the serum content of ET-1 and the expression of ETAR in myocardial tissue were increased (P<0.01), whereas expression of eNOS was decreased (P<0.01) in the model group. Compared with the model group, the serum content of ET-1 and the expression of ETAR in myocardial tissue were decreased (P<0.05), whereas expression of eNOS was increased (P<0.05) in the EA group.@*CONCLUSION@#EA intervention may alleviate hypertensive cardiac function damage by up-regulating the expression of eNOS protein in myocardial tissue, down-regulating the serum content of ET-1 and the expression of ETAR protein in myocardial tissue.

Mechanism of Mayuan tongbian zhitong decoction on improving slow-transmission constipation in rats by regulating AMPK/eNOS signaling pathway / 中国药房

OBJECTIVE To investigate the mechanism of Mayuan tongbian zhitong decoction on improving slow-transmission constipation（STC）in rats by regulating AMP activated protein kinase （AMPK）/endothelial nitric oxide synthase （eNOS）signaling pathway. METHODS The rats were randomly divided into blank group ，model group ，Mayuan tongbian zhitong decoction low-dose，medium-dose and high-dose groups （6，12，18 mg/kg），with 10 rats in each group. Except for blank group ，other groups were given Compound diphenoxylate suspension to induce STC model. After modeling ，blank group and model group were given normal saline intragastrically ，and Mayuan tongbian zhitong decoction groups were given relevant medicine intragastrically ， once a day ，for consecutive 2 weeks. The number of feces and water content of feces in each group were observed before and after treatment；the carbon powder propulsion rate of rats in each group was calculated ；the pathological structure of colon in each group was observed ；the levels of nitric oxide （NO）and nitric oxide synthase （NOS）in colon tissues of rats in each group were detected；the expressions of AMPK ，eNOS，mammalian target of rapamycin （mTOR），tuberous sclerosis complex 1（Tsc-1）， Tsc-2 and eukaryotic promoter 4E binding protein （4ebp）were also detected. The active ingredients of Cannabis sativa ，Citrus aurantium and Rehmannia glutinosa were screened from Mayuan tongbian zhitong decoction. The active ingredients with high Degree value were docked with AMPK and eNOS ，to verify the interaction. RESULTS Compared with before treatment ，the number and water content of feces were increased significantly in Mayuan tongbian zhitong decoction groups （P＜0.05）. Compared with blank group ，carbon powder propulsion rate of model group was decreased significantly （P＜0.05）； colonic structure was disordered ，and a large number of inflammatory cells were seen in submucosa ；the levels of NO and NOS in colon tissue as well as the protein expressions of AMPK ，eNOS，mTOR，Tsc-1，Tsc-2 and 4ebp were increased significantly （P＜0.05）. Compared with model group ，above indexes of Mayuan tongbian zhitong decoction groups （except for NOS in low-dose group ）were reserved significantly （P＜0.05）. In the molecular docking experiment ，the active components with the highest Degree values in C. sativa ，C. aurantium and R. glutinosa were（Z）-3-（4-hydroxy-3-methoxy-phenyl）-N-[2-（4-hydroxyphenyl）ethyl] acrylamide，nobiletin and stigmasterol. The binding energies of AMPK with these three components were －5.15，－4.61 and －4.83 kJ/mol，the binding energies of eNOS with these three components were －6.11，－5.40 and －5.91 kJ/mol. The conformations of these three compounds with AMPK and eNOS were stable and their binding activities were high. CONCLUSIONS Mayuan tongbian zhitong decoction can improve the constipation symptoms and intestinal function in STC model rats ，and its specific mechanism may be related to the inhibition of AMPK/eNOS signaling pathway.

Luteoloside protects the vascular endothelium against iron overload injury via the ROS/ADMA/DDAH II/eNOS/NO pathway / 中国天然药物

Iron overload injury is considered to be a part of blood stasis syndrome of arthralgia in traditional Chinese medicine. Its primary therapies include clearing heat and detoxification, activating blood circulation, and removing blood stasis. Lonicera japonica flos (LJF) has long been known as an excellent antipyretic and antidote. Luteoloside (Lut) is one of the main components of LJF and exhibits antioxidant, anti-inflammatory, and cytoprotective properties. However, the protection of Lut against iron overload injury and its underlying mechanisms remain unclear. Therefore, HUVECs were exposed to 50 μmol·L-1 iron dextran for 48 h to establish an iron overload damage model and the effects of Lut were assessed. Our results showed that 20 μmol·L-1 Lut not only increased cell viability and weakened LDH activity, but also significantly up-regulated DDAHⅡ expression and activity, increased p-eNOS/eNOS ratio and NO content, and reduced ADMA content in HUVECs exposed to iron overload. Furthermore, Lut significantly attenuated intracellular/mitochondrial ROS generation, improved SOD, CAT, and GSH-Px activities, reduced MDA content, maintained MMP, inhibited mPTP opening, prevented cyt c from mitochondria released into cytoplasm, reduced cleaved-caspase3 expression, and ultimately decreased cell apoptosis induced by iron overload. The effects of Lut were similar to those of L-arginine (an ADMA competitive substrate), cyclosporin A (a mPTP blocker agent), and edaravone (a free radical scavenger) as positive controls. However, addition of pAD/DDAH II-shRNA adenovirus reversed the above beneficial effects of Lut. In conclusion, Lut can protect HUVECs against iron overload injury via the ROS/ADMA/DDAH II/eNOS/NO pathway. The mitochondria are the target organelles of Lut's protective effects.

Nitric oxide regulates adhesiveness, invasiveness, and migration of anoikis-resistant endothelial cells

Anoikis is a type of apoptosis that occurs in response to the loss of adhesion to the extracellular matrix (ECM). Anoikis resistance is a critical mechanism in cancer and contributes to tumor metastasis. Nitric oxide (NO) is frequently upregulated in the tumor area and is considered an important player in cancer metastasis. The aim of this study was to evaluate the effect of NO on adhesiveness, invasiveness, and migration of anoikis-resistant endothelial cells. Here, we report that anoikis-resistant endothelial cells overexpress endothelial nitric oxide synthase. The inhibition of NO release in anoikis-resistant endothelial cells was able to decrease adhesiveness to fibronectin, laminin, and collagen IV. This was accompanied by an increase in cell invasiveness and migration. Furthermore, anoikis-resistant cell lines displayed a decrease in fibronectin and collagen IV protein expression after L-NAME treatment. These alterations in adhesiveness and invasiveness were the consequence of MMP-2 up-regulation observed after NO release inhibition. The decrease in NO levels was able to down-regulate the activating transcription factor 3 (ATF3) protein expression. ATF3 represses MMP-2 gene expression by antagonizing p53-dependent trans-activation of the MMP-2 promoter. We speculate that the increased release of NO by anoikis-resistant endothelial cells acted as a response to restrict the MMP-2 action, interfering in MMP-2 gene expression via ATF3 regulation. The up-regulation of nitric oxide by anoikis-resistant endothelial cells is an important response to restrict tumorigenic behavior. Without this mechanism, invasiveness and migration potential would be even higher, as shown after L-NAME treatment.

Protective effect of Sika Deer bone polypeptide extract on dexamethasone-induced osteoporosis in rats

BACKGROUND: Osteoporosis attacks approximately 10% of the population worldwide. Sika Deer (Cervus nippon), one of China's precious traditional medicinal animals, has been widely recorded in ancient Chinese medical books and claimed for centuries to have numerous medical benefits including bone strengthening. This study aimed to find the use of Sika Deer bone in treating osteoporosis according to traditional records and to investigate the protective effect of Sika Deer bone polypeptide extract on glucocorticoidinduced osteoporosis (GIOP) in rats. RESULTS: Sika Deer bone polypeptide extract could increase serum Ca2+ and BGP, decrease serum P3+, ALP, PTH, and CT, but had no effect on serum NO in rats with GIOP. The immunohistochemical iNOS results of the rats' distal femur were negative in each group. Besides the model group, the eNOS color reaction in osteoblasts was strongly positive in the other three groups. CONCLUSIONS: Sika Deer bone polypeptide extract can improve pathological changes in the microstructure and stimulate the expression of eNOS in osteoblasts. The protective effect on bone might be mediated by eNOS-dependent NO generation.

Forcing of cool and warm subsurface water events in Bahía Salinas, Costa Rica

Introduction: Bahía Salinas, on the north Pacific coast of Costa Rica, is a seasonal upwelling area. Sea temperature in Bahía Salinas could be modulated by synoptic and other large-scale systems. This region belongs to the Central American Dry Corridor (CADC), a sub-region in the isthmus that is relatively drier than the rest of the territory, which extends along the Pacific littoral from western Guatemala through northern Costa Rica. Objective: To study the warm and cold events that could be inferred by studying the sea subsurface temperature in Bahía Salinas, and also analyzing the large-scale conditions and synoptic systems of the historical sources when they occurred in order to identify the atmospheric mechanisms that favored their appearance. Methods: A Sea Subsurface Temperature Index was calculated using hourly data from seven stations located at three different points in Bahía Salinas. Records range from June 19, 2003 to December 5, 2017. Additionally, six meteorological stations, with hourly wind records, were used to create two wind indices. The Sea Subsurface Temperature Index was used to identify the warmest and coldest events in the bay. Wind indices and monthly meteorological bulletins were used to analyze the large-scale conditions and synoptic systems in which cold and warm events occurred in Bahía Salinas. Results: Mean sea temperature in Bahía Salinas is 25.2°C. Colder temperatures were observed in February-March, below 21°C. There were two maxima in May-June and August-October with temperatures above 27°C. In four of the five cold events studied, Northeasterly wind anomalies were observed in the Costa Rican North Pacific, associated with trade wind reinforcements; meanwhile westerly anomalies were observed in all the warm events, associated with weaker trade wind conditions. Conclusions: The main seasonal climate driver in Bahía Salinas is the North Atlantic Subtropical High because its latitudinal migration is associated with the strength of the trade winds over Central America. Seasonal upwelling is modulated also by two synoptic scale climate features, the boreal winter arrival of cold front outbreaks and the winter maximum of the easterly Caribbean Low-Level Jet. El Niño-Southern Oscillation is also an important modulator of the sea temperature variability, since warm and cool events are related with positive and negative sea temperature anomalies.

Introducción: Bahía Salinas, en el Pacífico norte de Costa Rica, es un área de afloramiento estacional. La temperatura del mar en Bahía Salinas puede ser modulada por sistemas sinópticos de gran escala. Esta región pertenece al Corredor Seco Centroamericano (CSC), una subregión del istmo relativamente más seca que el resto del territorio, que se extiende a lo largo del litoral Pacífico desde el oeste de Guatemala hasta el norte de Costa Rica. Objetivo: Estudiar los eventos cálidos y fríos que se podrían inferir al estudiar la temperatura subsuperficial del mar en Bahía Salinas, y también analizar las condiciones y sistemas sinópticos a gran escala de las fuentes históricas en las que ocurrieron para identificar los mecanismos atmosféricos que favorecieron su desarrollo. Métodos: Se calculó un índice de temperatura subsuperficial del mar utilizando datos horarios de siete estaciones ubicadas en tres puntos diferentes en Bahía Salinas. Los registros van desde el 19 de junio de 2003 al 5 de diciembre de 2017. Además, se utilizaron seis estaciones meteorológicas, con registros de viento horario, para crear un índice de viento zonal y otro meridional. Se utilizó el índice de temperatura subsuperficial del mar para identificar los eventos más cálidos y más fríos en la bahía. Se utilizaron los índices de viento y boletines meteorológicos mensuales para analizar las condiciones y sistemas sinópticos a gran escala en los que se dieron los eventos fríos y cálidos en Bahía Salinas. Resultados: La temperatura media del mar en Bahía Salinas es de 25.2 °C. Se observaron temperaturas más frías en febrero-marzo, por debajo de los 21 °C. El ciclo anual presentó dos máximos en mayo-junio y agosto-octubre con temperaturas superiores a 27 °C. En cuatro de los cinco eventos fríos estudiados, se observaron anomalías de los vientos del noreste en el Pacífico Norte costarricense, asociadas a refuerzos de los vientos alisios; mientras tanto, se observaron anomalías del oeste en todos los eventos cálidos, asociadas con condiciones de vientos alisios más débiles. Conclusiones: El principal forzante climático en Bahía Salinas es la Alta Subtropical del Atlántico Norte ya que su migración latitudinal está asociada con la fuerza de los vientos alisios sobre América Central. La surgencia estacional está modulada también por dos características climáticas de escala sinóptica en el invierno boreal, la llegada de frentes fríos y el máximo de la Corriente en Chorro de Bajo Nivel del Caribe Oriental. El Niño-Oscilación del Sur también es un modulador importante de la variabilidad de la temperatura del mar, ya que los eventos cálidos y fríos están relacionados con anomalías positivas y negativas de la temperatura del mar.

Hydrographic variability in the Gulf of Papagayo, Costa Rica during 2017-2019

Introduction: The Gulf of Papagayo (GP) is a site of socioeconomic importance located in the North Pacific of Costa Rica. The ecosystem services of this site represent a benefit in local communities, and its dynamics are influenced by a coastal upwelling system that affects fishing and commercial activity. Objective: The objective of this study was to characterize the spatio-temporal variability of the main hydrographic parameters through measurements in situ during the period 2017-2019. Methods: Eight measurement campaigns were carried out, where a CTD probe was deployed to perform vertical profiles in 23 stations distributed throughout the GP, to characterize the variations in temperature, salinity, dissolved oxygen and chlorophyll concentration. Results: A minimum in surface and bottom temperature associated with upwelling caused by the wind was found in the first period of the year. The increase in salinity was associated with the decrease in temperature, being its highest value in the first period of the year, decreasing until reaching a minimum in November. The maximum chlorophyll concentration ​​coincided with the lowest surface temperatures and the minimum oxygen values were associated ​​with the minimum bottom temperatures, both occurring during the upwelling season. The parameter distribution was similar on dry and rainy seasons in stations located inside Bahía Culebra, likely attributed to the bathymetry effect. Conclusions: Bathymetry determines a south-north asymmetry for salinity and temperature. Subsurface cooling events coincide with strong wind periods. Upwelling influences the surface and bottom hydrographic dynamic in GP and determines the seasonal variability. The negative ENSO phase of 2018 corresponded with the strongest upwelling period, possibly promoting the interaction of upwelled coastal waters and the Costa Rica Thermal Dome.

Introducción: El Golfo de Papagayo (GP) es un sitio de alta importancia socioeconómica ubicado en el Pacifico Norte de Costa Rica. Los servicios ecosistémicos de este sitio representan un beneficio a las comunidades locales, y su dinámica está influenciada por un sistema de surgencia costera que influye en la actividad pesquera y comercial. Objetivo: El objetivo de este estudio fue caracterizar la variabilidad espacio-temporal de los principales parámetros hidrográficos a través de mediciones in situ durante el período 2017-2019. Metodología: Se realizaron 8 campañas de medición, donde se desplegó una sonda CTD para realizar perfiles verticales en 23 estaciones distribuidas en todo el GP, para caracterizar las variaciones de temperatura, salinidad, oxígeno disuelto y concentración de clorofila. Resultados: En el primer período del año se encontró una temperatura mínima de superficie y fondo asociada a la surgencia causada por el viento. El aumento de salinidad estuvo asociado a la disminución en la temperatura, siendo su valor más alto en el primer período del año y disminuyendo hasta alcanzar un mínimo en Noviembre. Los valores más altos de clorofila estuvieron relacionados con las temperaturas más bajas en superficie y los valores más bajos de oxígeno con las temperaturas más bajas en fondo. Se caracterizó la hidrografía de Bahía Culebra en relación con la parte externa de GP. Conclusiones: La batimetría determina una asimetría sur-norte de salinidad y temperatura. Los eventos de enfriamiento subsuperficiales coinciden con períodos de fuertes vientos. La surgencia influye en la dinámica hidrográfica de superficie y fondo en GP y determina la variabilidad interanual. El evento La Niña de 2018 mostró el período de surgencia más fuerte, posiblemente promoviendo la interacción de las aguas costeras y el Domo Térmico de Costa Rica.

Gualou-Xiebai-Banxia decoction protects against type II diabetes with acute myocardial ischemia by attenuating oxidative stress and apoptosis via PI3K/Akt/eNOS signaling / 中国天然药物

Gualou-Xiebai-Banxia decoction has a long history of medical use for treating cardiovascular diseases in China. In this study, we investigated the protective effect and underlying mechanisms GXB in type II diabetes with acute myocardial ischemia (T2DM-AMI) rats. We hypothesized that GXB may display its protective effect on T2DM-AMI by reducing endothelial progenitor cells (EPCs) apoptosisviaactivating PI3K (phosphatidyl inositol 3-kinase)/Akt (serine/threonine protein kinase B)/eNOS (endothelial nitric oxide synthase) signaling. Rats were challenged with a high-fat diet and intraperitoneal injection of streptozotocin to induce a model of type II diabetes mellitus (T2DM) and coronary ligation to induce acute myocardial infarction (AMI). Changes in metabolites were assessed via enzyme-linked immunoassay and biochemical examination. The number and apoptosis rate of EPCs in peripheral blood were detected by flow cytometry. Target mRNAs and proteins in EPCs were analyzed by RT-PCR and Western blot analysis. The results demonstrated that GXB treatment decreased T2DM-AMI-associated changes in plasma fasting blood glucose, muscular enzymes, and blood lipids, and reduced oxidative stress. Furthermore, EPC apoptosis was increased in T2DM-AMI rats and was associated with decreased mRNA and protein levels of PI3K, Akt, and eNOS compared to the controls. Conversely, T2DM-AMI rats treated with GXB exhibited more circulating EPCs and downregulated levels of cell apoptosis, combined with increased mRNA and protein levels of PI3K, Akt, and eNOS compared to those of untreated T2DM-AMI rats. Our study showed that GXB treatment mitigated EPC apoptosis and promoted PI3K/Akt/eNOS signaling in T2DM-AMI rats.

Screening of mRNA expression differences of PI3K/Akt/eNOS in the aortic tissue of rats exposed to sodium fluoride based on mRNA sequencing / 中华地方病学杂志

Objective:To explore the effect of fluoride exposure on the gene expression of phosphatidylinositol-3-kinase/protein kinase B/endothelial nitric oxide synthase (PI3K/Akt/eNOS) in rat aortic tissue, and to provide a theoretical basis for studying the mechanism of cardiovascular injury caused by endemic fluorosis.Methods:A total of 40 male Wistar rats were divided into 4 groups (10 rats in each group) via the random number table method according to body weight (80 - 100 g), namely control group (drinking distilled water), low-dose, medium-dose and high-dose groups [drinking distilled water containing 50, 100 and 150 mg/L sodium fluoride (NaF), respectively]. The rats were free to drink and eat. After feeding for 90 days, rats were sacrificed and the aortic tissue was taken. Three aortic tissue samples from the control group and the high-dose group were taken for mRNA sequencing, the differential genes were screened, and the differential genes were analyzed by GO function enrichment analysis and KEGG function enrichment analysis. At the same time, the mRNA expression levels of PI3K, Akt and eNOS in the aortic tissue of rats in each group were determined by real-time fluorescence quantitative PCR.Results:Compared with control group, there were 756 differential genes in high-dose group, including 654 up-regulated genes and 102 down-regulated genes. These differential genes were mainly related to biological processes such as muscle contraction, muscle regulation, muscle tissue development, striated muscle cell development, muscle cell differentiation, blood circulation regulation and striated muscle tissue development. They were mainly enriched in cyclic guanosine phosphate (cGMP-PKG) signaling pathway, relaxin signaling pathway and PI3K/Akt signaling pathway, etc. Compared with control group, the mRNA expression levels of PI3K and eNOS in aortic tissue of rats in low-dose, medium-dose and high-dose groups were significantly reduced ( P < 0.05); the mRNA expression level of Akt in low-dose group was significantly increased ( P < 0.05). Conclusion:Fluoride exposure has certain effects on the function and gene expression of rat aortic tissue, and PI3K/Akt/eNOS signaling pathway may play an important role in the process of fluoride induced aortic tissue injury in rats.

Use of network pharmacology to analyze compound reserpine and triamterene tablets in the treatment of hypertension / 药学学报

Compound reserpine and triamterene tablets (CRTT), a compound antihypertensive drug developed by Chinese scientists, is still widely used in clinical practice. However, the mechanisms by which CRTT treats hypertension remain to be fully understood. This study used network pharmacology to analyze CRTT's antihypertensive mechanisms with in vitro experiments. The targets of the four chemical components of CRTT were collected from the Swiss Target Prediction database; 1 828 protein targets related to hypertension were collected from the Therapeutic Target Database (TTD) and Online Mendelian Inheritance in Man (OMIM) database. The CRTT-hypertension network model was constructed using a search tool for recurring instances of neighbouring genes (STRING). Gene ontology (GO) and pathway enrichment analysis of targets of interest was conducted with the Metascape database. In the in vitro study, human umbilical vein endothelial cells (HUVEC) and vascular smooth muscle cells (VSMC) were treated with 1 μmol·L-1 angiotensin Ⅱ (AngⅡ) and CRTT was administered at concentrations of 0.01, 0.1, and 1 μmol·L-1. Changes in the phosphatidylinositol-3-kinase/protein serine threonine kinase/endothelial nitric oxide synthase (PI3K/Akt/eNOS) pathway in HUVEC and the cyclic guanosine monophosphate/cGMP-dependent protein kinase (cGMP/PKG) pathway in VSMC were determined by Western blot. Network pharmacological analysis revealed that the antihypertensive effect of CRTT is closely associated with biological pathways such as vascular tone regulation, adrenergic receptor activation, protein kinase activity and signaling pathways such as the cGMP/PKG signaling pathway, vascular smooth muscle contraction, neuroactive ligand-receptor interaction, adrenergic signaling in cardiomyocytes and calcium signaling pathways. The in vitro study confirmed that CRTT increased the levels of phosphorylated phosphatidylinositol-3-kinase (p-PI3K), phosphorylated protein serine threonine kinase (p-Akt), phosphorylated endothelial nitric oxide synthase (p-eNOS) in HUVEC and the levels of eNOS, phosphorylated vasodilator-stimulated phosphoprotein (p-VASP), and PKG in VSMC through multiple targets and pathways. These results suggest that the activation of PI3K/Akt/eNOS pathway and endothelial-dependent NO/cGMP signaling may be involved in the CRTT-mediated hypotensive effect.

Effect of Danggui Buxuetang on Functional Activity of Endothelial Progenitor Cells Exposed to Shear Stress / 中国实验方剂学杂志

Objective:To investigate the effect of Danggui Buxuetang（DGBX）on the functional activity of rat endothelial progenitor cells（EPCs）exposed to different luminar shear stress （SS）. Method:EPCs isolated from rat bone marrow were incubated on a parallel plate flow chamber at a steady SS of 0， 0.12， 1.2， 2.4 Pa for 6 h，then the cells exposed to different SS were randomly divided into 8 groups： control group （perfused with serum free medium），simvastatin group（0.1 μmol·L^-1simvastatin），3 DGBX groups（low，medium，high-dose DGBX）and 3 inhibitor groups（3 DGBX groups with LY294002）. After 12 h，the samples were collected for the detection of cell proliferation ，migration，tubule formation ，the secretion of nitric oxide （NO） ，and the expressions of endothelial nitric oxide synthase（eNOS） mRNA and protein kinase B（Akt），respectively. Result:Compared with the control group，simvastatin and DGBX（high-dose）could both promote the functional activities and NO secretion，and up-regulate the expressions of eNOS mRNA and Akt protein in EPCs exposed to different SS（<italic>P</italic><0.05），while DGBX（mid-dose）could do these only at 0 Pa. However，LY294002 could inhibit all effects of DGBX on EPCs. Conclusion:SS seems to play an important role in the effect of DGBX on EPCs，and DGBX could promote the functional activity of EPCs exposed to SS by up-regulating the expressions of NO/eNOS/Akt.

Effect of Shuangshen Xionglian Granule on Vasodilation and PI3K/Akt/eNOS Pathway in Hyperhomocysteinemia Chronic Kidney Disease Rats / 中国实验方剂学杂志

Objective:To study the effect of Shuangshen Xionglian （SSXL） granules on vasculopathy and phosphatidylinositol 3 kinase （PI3K）/serine threonine kinase （Akt）/nitrogen oxide synthase （eNOS） signal in hyperhomocysteinemia chronic kidney disease rats. Method:Rats were randomly divided into 5 groups： sham operation group， model group， and high， medium and low-dose （8， 4， 2 g·kg-1） SSXL groups. The model of hyperhomocysteinemia chronic kidney disease in rats was established with high methionine feed combined with 5/6 nephrectomy. After 5/6 nephrectomy， continuous intragastric administration lasted for four weeks. Arterial blood pressure was measured at the 4th and 8th weeks after operation. At the end of the 8th week after the operation， blood was collected to determine serum creatinine， urea nitrogen， homocysteine （Hcy）， methionine and blood lipid. Western blot was used to detect the expressions of PI3K/Akt/eNOS pathway-related proteins， such as p-p85， p-Akt and p-Ser177 in thoracic aorta， and serum NO and eNOS were measured. The changes of endothelium-dependent relaxation and non-endothelium-dependent relaxation were measured by the method of isolated thoracic aorta ring. Pathological htoxylin eosin （HE） staining was used to observe the changes of renal tissue and thoracic aorta. Result:At the 8th week of the experiment， compared with the sham operation group， arterial systolic blood pressure， serum urea nitrogen， creatinine， Hcy， methionine， total cholesterol and low-density lipoprotein of the model group were significantly increased. Four weeks later after administration， arterial systolic blood pressure， serum urea nitrogen， Hcy， methionine， serum total cholesterol and serum low-density lipoprotein were significantly reduced in each dose group （P<0.05， P<0.01）. The creatinine in the SSXL 8， 4 g·kg-1 group was significantly reduced （P<0.05）. The nitric oxide content of SSXL in each dose groups were increased compared with that in the model group （P<0.05， P<0.01）， and the serum eNOS activity of the SSXL in the SSXL 8 g·kg-1 group was significantly increased compared with that in the model group （P<0.05）. The endothelium dependent and non-endothelium dependent vasodilation of thoracic aortic rings in the model group were significantly damaged. The cumulative concentration of acetylcholine （1×10-5.5~1×10-4 mmo1·L-1） in the SSXL 8 g·kg-1 group was significantly improved （P<0.05， P<0.01）. The diastolic degree of the vascular ring in the SSXL 8 g·kg-1 group was significantly higher than that in the model group （P<0.05）. Western blot results showed that the expressions of p-85， p-Akt and p-Ser177 in blood vessels increased in the sham group compared with those in the model group （P<0.01）. Compared with the model group， the phosphorylation level of this pathway was increased in the SSXL groups， and the expressions of p-Akt and p-Ser177 in the SSXL 8 g·kg-1 group were significantly increased （P<0.05）. The pathological results showed that the pathological changes of thoracic aorta and renal tissue in the dosages of SSXL were significantly reduced compared with those in the model group. Conclusion:SSXL granules can improve hyperhomocysteine and dyslipidemia in rats of chronic kidney disease with hyperhomocysteine， reduce serum creatinine， urea nitrogen levels and arterial systolic blood pressure， and improve vascular morphology and diastolic function， which may be related to the regulation of the PI3K/Akt/eNOS signaling pathway.

Effect of Exendin-4 on endothelial progenitor cell function and AKT/eNOS signaling pathway in a mouse model of type 1 diabetes / 中国药理学通报

Aim To investigate the effect of Exendin4 on proliferation, migration, adhesion and senescence of endothelial progenitor cells (EPCs) in type I diabetic mice and its possible mechanism. Methods EPCs from 6-month diabetic mice were isolated and cultured by density gradient centrifugation. Cells were treated with different concentrations of Exendin-4 (1, 5, 10, 25 μmol · L