Real-time fetal monitoring using photoacoustic measurement of placental oxygen saturation in a rabbit hypoxia model.

INTRODUCTION: Ensuring adequate fetal oxygenation is an essential aim of fetal monitoring. The purpose of this study was to establish a basic technique for real-time measurement of blood oxygen saturation of the placenta by photoacoustic (PA) technique as a new fetal monitoring method. METHODS: The hypoxia model established in our previous study was applied to 7 pregnant rabbits. Three phases were induced: normal phase, hypoxia phase, and recovery phase. Three methods were simultaneously used for real-time fetal monitoring: fetal heat rate (FHR) monitoring, oxygen saturation (SO2) measurement by near-infrared spectroscopy (SNO2), and placenta SO2 measured by PA technique (SplO2). The maternal hypoxia was assessed by skin SO2 measured by PA technique (SsO2), and arterial blood SO2 by blood gas analysis (SaO2). RESULTS: The average of SplO2 in normal phase was 52.6 ± 13.9 %. The averages of SNO2, SSO2, and SplO2 in the seven rabbits changed in parallel from the normal phase to hypoxia phase. In the recovery phase, the SplO2 rose in parallel with recovery of SaO2. There was lag in increase of the FHR compared to the change in the other values. In the detailed analysis of PA signals from the labyrinth and decidua, a unique change in oxygen saturation was seen in one case. DISCUSSION: Results of this study showed that sensitivity of our novel PA technique in detecting tissue hypoxia was similar to near-infrared spectroscopy (NIRS). As an advantage, unlike NIRS, monitoring with PA technique was unaffected by ischemia and surface changes in oxygen saturation because of its higher spatial resolution. We conclude that PA technique provides more accurate information about fetal blood placenta than NIRS. Ultrasound imaging, combined with oxygen saturation monitoring by PA technique, would improve fetal monitoring and fetal diagnosis in the future.

Mechanism of Yiqi Jiedu Prescriptions in Protection of Mitochondria in PC12 Cells Against Hypoxia Injury Based on Energy Metabolism / 中国实验方剂学杂志

ObjectiveTo establish an evaluation method for mitochondrial energy metabolism with Seahorse analyzer and investigate the protective effect of Yiqi Jiedu prescriptions （YQ） on mitochondria in rat adrenal pheochromocytoma （PC12） cells against hypoxia injury. MethodThe PC12 cell injury model was induced in vitro using hypoxic chambers. Five groups were set up， ie， a control group， a model group （model）， high- （25 µmol·L-1）， medium- （5 µmol·L-1） and low-dose （1 µmol·L-1） YQ groups， and a positive drug trimetazidine （TMZ） group， with three replicate wells in each group. The experiment was repeated three times. The established method for energy metabolism analysis was used to assay the activity of mitochondrial complex in cells and screen the optimal dosing concentration. Subsequently， the YQ group and modified YQ groups were set up， and the aerobic respiration and glycolysis function were assayed by the Seahorse analyzer. According to the non-mitochondrial oxygen consumption， proton leakage， basal respiration， maximum respiration， ATP production， and potentially improved respiration， the effects of modified YQ groups on the aerobic respiration of mitochondria damaged by hypoxia were evaluated by principal component analysis （PCA） and variable importance in projection （VIP）. The expression of cytochrome C， B-cell lymphoma-2 （Bcl-2）， and Bcl-2-associated X protein （Bax） was detected by Western blot. ResultCompared with the groups of other concentrations， the optimal dosing concentration of carbonyl cyanide-4 （trifluoromethoxy）phenylhydrazone （FCCP） was 2 µmol·L-1. Compared with the model group， the medium-dose YQ group showed enhanced mitochondrial complex activity （P<0.05）. The YQ groups were superior to the model group in improvement （P<0.01）. The combination of ginsenoside and geniposide showed the optimal effect among the modified YQ groups （P<0.01）. VIP analysis revealed that for the improvement of mitochondrial respiratory function， the contribution of geniposide in YQ was the greatest. Compared with the model group， the high-dose YQ group displayed reduced leakage of mitochondrial cytochrome C （P<0.01）， decreased expression of Bax protein （P<0.01）， and increased expression of Bcl-2 protein （P<0.05， P<0.01）. ConclusionA cellular， high-throughput quantitative evaluation method for mitochondrial energy metabolism was established， which demonstrated that YQ could significantly improve the impaired mitochondrial energy metabolism in PC12 cells damaged by hypoxia， and the underlying mechanism might be related to the protection against mitochondrial apoptosis.

Acetazolamide Improves Right Ventricular Function and Metabolic Gene Dysregulation in Experimental Pulmonary Arterial Hypertension.

Background: Right ventricular (RV) performance is a key determinant of mortality in pulmonary arterial hypertension (PAH). RV failure is characterized by metabolic dysregulation with unbalanced anaerobic glycolysis, oxidative phosphorylation, and fatty acid oxidation (FAO). We previously found that acetazolamide (ACTZ) treatment modulates the pulmonary inflammatory response and ameliorates experimental PAH. Objective: To evaluate the effect of ACTZ treatment on RV function and metabolic profile in experimental PAH. Design/Methods: In the Sugen 5416/hypoxia (SuHx) rat model of severe PAH, RV transcriptomic analysis was performed by RNA-seq, and top metabolic targets were validated by RT-PCR. We assessed the effect of therapeutic administration of ACTZ in the drinking water on hemodynamics by catheterization [right and left ventricular systolic pressure (RVSP and LVSP, respectively)] and echocardiography [pulmonary artery acceleration time (PAAT), RV wall thickness in diastole (RVWT), RV end-diastolic diameter (RVEDD), tricuspid annular plane systolic excursion (TAPSE)] and on RV hypertrophy (RVH) by Fulton's index (FI) and RV-to-body weight (BW) ratio (RV/BW). We also examined myocardial histopathology and expression of metabolic markers in RV tissues. Results: There was a distinct transcriptomic signature of RVH in the SuHx model of PAH, with significant downregulation of metabolic enzymes involved in fatty acid transport, beta oxidation, and glucose oxidation compared to controls. Treatment with ACTZ led to a pattern of gene expression suggestive of restored metabolic balance in the RV with significantly increased beta oxidation transcripts. In addition, the FAO transcription factor peroxisome proliferator-activated receptor gamma coactivator 1-alpha (Pgc-1α) was significantly downregulated in untreated SuHx rats compared to controls, and ACTZ treatment restored its expression levels. These metabolic changes were associated with amelioration of the hemodynamic and echocardiographic markers of RVH in the ACTZ-treated SuHx animals and attenuation of cardiomyocyte hypertrophy and RV fibrosis. Conclusion: Acetazolamide treatment prevents the development of PAH, RVH, and fibrosis in the SuHx rat model of severe PAH, improves RV function, and restores the RV metabolic profile.

Efficacy of the thromboxane receptor antagonist NTP42 alone, or in combination with sildenafil, in the sugen/hypoxia-induced model of pulmonary arterial hypertension.

NTP42 is a novel antagonist of the thromboxane A2 receptor (TP) in development for the treatment of pulmonary arterial hypertension (PAH). Recent studies demonstrated that NTP42 and TP antagonism have a role in alleviating PAH pathophysiology. However, the efficacy of NTP42 when used in combination with existing PAH therapies has not yet been investigated. Herein, the Sugen 5416/hypoxia (SuHx)-induced PAH model was employed to evaluate the efficacy of NTP42 when used alone or in dual-therapy with Sildenafil, a PAH standard-of-care. PAH was induced in rats by injection of Sugen 5416 and exposure to hypoxia for 21 days. Thereafter, animals were treated orally twice-daily for 28 days with either vehicle, NTP42 (0.05 mg/kg), Sildenafil (50 mg/kg), or NTP42+Sildenafil (0.05 mg/kg + 50 mg/kg, respectively). While Sildenafil or NTP42 mono-therapy led to non-significant reductions in the SuHx-induced rises in mean pulmonary arterial pressure (mPAP) or right ventricular systolic pressure (RSVP), combined use of NTP42+Sildenafil significantly reduced these increases in mPAP and RVSP. Detailed histologic analyses of pulmonary vessel remodelling, right ventricular hypertrophy and fibrosis demonstrated that while NTP42 and Sildenafil in mono-therapy resulted in significant benefits, NTP42+Sildenafil in dual-therapy showed an even greater benefit over either drug used alone. In summary, combined use of NTP42+Sildenafil in dual-therapy confers an even greater benefit in treating or offsetting key aetiologies underlying PAH. These findings corroborate earlier preclinical findings suggesting that, through antagonism of TP signalling, NTP42 attenuates PAH pathophysiology, positioning it as a novel therapeutic for use alone or in combination therapy regimens.

Tissue-Specific Peculiarities of Vibration-Induced Hypoxia in Rabbit Liver and Kidney.

Activity of the energy production systems in rabbit liver and kidney under conditions of unfavorable vibration exposure was studied by the polarography method using a galvanic-type closed oxygen sensor. The rate of oxidation of endogenous substrates by mitochondria was determined by the tissue and was 5.2±0.6 and 8.13±1.4 (ng-atom O)×min-1×mg-1 protein for liver and kidney of intact animals, respectively. After 21 vibration sessions against the background of inhibition of NAD-dependent substrate oxidation in liver mitochondria, the rate metabolism of exogenous succinic acid increased by 44% and then decreased with prolongation of the effect, which indicated impaired function of the respiratory chain. Similar fluctuations of the parameters were revealed in kidney mitochondria, though their amplitude was lower. The study of bioenergetic mechanisms of hypoxia in various tissues makes it possible to determine the targets for the pharmacological action of antihypoxic drugs.

CoCl2 increases the expression of hypoxic markers HIF-1α, VEGF and CXCR4 in breast cancer MCF-7 cells.

The aim of the present study was to investigate the effect of a hypoxic environment on the biological behavior of breast cancer MCF-7 cells, using CoCl2 to mimic the hypoxia model in breast cancer cells. Using 50, 100, 150 and 200 µM CoCl2 as a hypoxic inducer, a hypoxic model was established in MCF-7 cells in vitro. MTT, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) and western blotting assays were performed to detect MCF-7 cell proliferation under hypoxic conditions and the expression of the hypoxic markers hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and C-X-C motif chemokine receptor 4 (CXCR4) mRNA and that of the associated proteins. The RT-qPCR results revealed that there were no obvious changes in the expression of HIF-1α mRNA; however, the expression of CXCR4 and VEGF mRNA increased significantly following treatment with different CoCl2 concentrations (P<0.05). The results of western blotting identified that CoCl2 significantly induced the expression of HIF-1α, CXCR4 and VEGF proteins (P<0.05). The MTT assay revealed that different concentrations of CoCl2 inhibited the proliferation of MCF-7 cells. The TUNEL assay demonstrated that CoCl2 was able to trigger apoptosis of MCF-7 cells. Therefore, the results of the present study identified that CoCl2 is able to control MCF-7 cell proliferation and apoptosis, also increasing the expression of HIF-1α, CXCR4 and VEGF. The present study may aid the discovery of a novel method to prevent cell damage and decrease cell proliferation in order to prevent the occurrence and development of breast cancer.

Renal Denervation Reduces Pulmonary Vascular Remodeling and Right Ventricular Diastolic Stiffness in Experimental Pulmonary Hypertension.

Neurohormonal overactivation plays an important role in pulmonary hypertension (PH). In this context, renal denervation, which aims to inhibit the neurohormonal systems, may be a promising adjunct therapy in PH. In this proof-of-concept study, we have demonstrated in 2 experimental models of PH that renal denervation delayed disease progression, reduced pulmonary vascular remodeling, lowered right ventricular afterload, and decreased right ventricular diastolic stiffness, most likely by suppression of the renin-angiotensin-aldosterone system.

RP5063, a novel, multimodal, serotonin receptor modulator, prevents Sugen 5416-hypoxia-induced pulmonary arterial hypertension in rats.

RP5063, a multimodal dopamine (DA) and serotonin (5-HT) modulator with high affinity for DA2/3/4 and 5-HT2A/2B/7 receptors and moderate affinity for SERT, is a novel therapeutic of special interest in the treatment of pulmonary arterial hypertension (PAH). Evidence indicates that therapeutics targeting the 5-HT2A/2B receptors can influence the pathogenesis of PAH. However, the therapeutic effect of RP5063 in humans has yet to be investigated. A Sugen 5416-hypoxia (SuHx)-induced PAH model was used to evaluate twice-daily (b.i.d.) RP5063 at 10mg/kg (RP-10) and 20mg/kg (RP-20), as compared with positive (sildenafil 50mg/kg b.i.d.; Sil-50) and negative controls (SuHx+vehicle; SuHx+veh), in 24 adult male Wistar-Kyoto rats. RP5063 showed significantly lower systolic pulmonary arterial (both doses) and systolic right ventricular (RP-10) pressures, and improvement in oxygen saturation (RP-20). It significantly reduced small-vessel wall thickness (RP-20), lowered the percentage of muscular vessels (both doses). Both doses limited arterial obliteration due to endothelial cell proliferation, prevented plexiform lesion formation, and stemmed the release of leukotriene B4. Sildenafil showed statistically greater effects on vessel structure than that seen in both RP5063 groups and improved oxygen saturation. Additionally, Sildenafil did not demonstrate any significant effect on arterial obliteration, plexiform lesion development, or pulmonary arterial or right ventricular pressure. As PAH gains in severity, the impact of RP5063 inhibition of 5HT2B increases, preventing arterial constriction and improving pulmonary hemodynamics. Due to its functional, structural, and chemokine effects, RP5063 represents a promising candidate for investigation in late-phase PAH.

Regulation and function of miR-214 in pulmonary arterial hypertension.

Dysregulation of microRNAs (miRNAs) can contribute to the etiology of diseases, including pulmonary arterial hypertension (PAH). Here we investigated a potential role for the miR-214 stem loop miRNA and the closely linked miR-199a miRNAs in PAH. All 4 miRNAs were upregulated in the lung and right ventricle (RV) in mice and rats exposed to the Sugen (SU) 5416 hypoxia model of PAH. Further, expression of the miRNAs was increased in pulmonary artery smooth muscle cells exposed to transforming growth factor ß1 but not BMP4. We then examined miR-214(-/-) mice exposed to the SU 5416 hypoxia model of PAH or normoxic conditions and littermate controls. There were no changes in RV systolic pressure or remodeling observed between the miR-214(-/-) and wild-type hypoxic groups. However, we observed a significant increase in RV hypertrophy (RVH) in hypoxic miR-214(-/-) male mice compared with controls. Further, we identified that the validated miR-214 target phosphatase and tensin homolog was upregulated in miR-214(-/-) mice. Thus, miR-214 stem loop loss leads to elevated RVH and may contribute to the heart failure associated with PAH.

Anticonvulsant activity of bacopa monniera in rodents / Anticonvulsivante atividade de bacopa monniera em roedores

Bacopa monnieri (L), belonging to the Scrophulariaceae family and commonly known as Brahmi, is well known in India for its CNS activity but its neuropharmacological effect has not yet been explored. In the present study, the antiepileptic effects of the plant were investigated. The ethanolic extract of Bacopa monniera was tested for anticonvulsant activity in albino rats, using different convulsive models. The ethanolic extract of leaves produced significant anticonvulsant activity for all the different models studied. The present study shows a probable mechanism of action similar to that of benzodiazepines (GABA agonist). Thus, these results emphasize the need to diversify by using alternative therapeutic approaches pertaining to herbal medicine, where a single easily available plant may provide solutions to several therapeutic challenges, as observed in the anticonvulsant action of ethanolic extract of B. monniera.

Bacopa monniera, da família Scrophulariaceae, e comumente denominada Brahmi, é bem conhecida na Índia por sua atividade no Sistema Nervoso Central, mas seu efeito neurofarmacológico não foi, ainda, explorado. No presente estudo, investigaram-se os efeitos antiepilépticos da planta. O extrato etanólico da Bacopa monniera foi testado quanto à atividade anticonvulsivante em ratos albinos, utilizando-se diferentes modelos de convulsão. O extrato etanólico das folhas produziu atividade anticonvulsivante significativa para todos os diferentes modelos estudados. O presente estudo mostra provável mecanismo de ação semelhante ao dos benzodiazepínicos (agonista do GABA). Assim sendo, esses resultados enfatizam a necessidade de diversificar, utilizando-se abordagens terapêuticas alternativas da medicina natural, em que uma planta facilmente disponível pode fornecer soluções para vários desafios terapêuticos, como o observado na ação anticonvulsivante do extrato etanólico de Bacopa monniera.

Protective Effect of Tongsaimai Pellets and Butylphthalide to PC12 Cell in Hypoxia/Hypoglycemia Model / 中国中医药信息杂志

Objective To discuss the protective effect of Tongsaimai pellets(TSMP) and butylphthalide(NBP) on PC12 cell in the hypoxia/hypoglycemia model.Methods Two ischemia models including hypoxia,hypoglycemia models were used to assay the anti-ischemic roles of TSMP and NBP in cultured PC12.Results TSMP and NBP possessed obvious protective effects on PC12 cells from two injured models.Both of them could increase the number of living cells and decrease LDH activity significantly,particularly in hypoglycemia injured model.Conclusion TSM and NBP have protective effect on PC12 cells from two injured models effectively in vitro.

Antihypoxic Effect of Orientoside on Hypoxia Model Mice / 中国药房

OBJECTIVE:To evaluate the antihypoxic effect of orientoside on hypoxia model rats.METHODS:The hy-poxia rats model was established through normobaric hypoxia,poisoning with sodium nitrite,potassium cyanide and lidocaine,trachea occlusion,decapitation,etc.20minutes prior to the modeling,the rats were administered with the corresponding drugs with the anti-hypoxic effects observed.RESULTS:As compared with placebo group,the survival time of rats under nor-mobaric hypoxia,poisoned by sodium nitrite,potassium cyanide and lidocaine,and the electrocardiograph extinction time after trachea occlusion and the gasping time of mice after decapitation were all significantly prolonged by orientoside.CONCLU-SION:Orientoside has antihypoxic effect on hypoxia model rats.