Blueberry extract decreases oxidative stress and improves functional parameters in lungs from rats with pulmonary arterial hypertension

Blueberry Extract and Resistance Training Prevent Left Ventricular Redox Dysregulation and Pathological Remodeling in Experimental Severe Pulmonary Arterial Hypertension

OBJECTIVE

To investigate whether the regular administration of blueberry extract and low-intensity resistance exercise training (RT), either alone or in combination, during the development of monocrotaline (MCT)-induced severe pulmonary arterial hypertension (PAH) in rats protect the left ventricle (LV) from redox dysregulation and pathological remodeling.

METHODS

Groups of seven male Wistar rats were formed for the experiment: sedentary control; sedentary hypertensive; sedentary hypertensive blueberry; exercise hypertensive; and exercise hypertensive blueberry. PAH was experimentally induced through a single intraperitoneal administration of MCT at a dose of 60 mg/kg. One day after injection, the blueberry groups started receiving a daily dose of blueberry extract (100 mg/kg) by gavage, while the exercise groups initiated a three-week program of RT (ladder climbing; 15 climbs carrying 60% of maximum load; one session/day; 5 times/week). Echocardiographic evaluations were conducted 23 days after injection, and the rats were euthanized the next day to harvest LV tissue.

RESULTS

Separately, blueberry extract and RT mitigated augments in pulmonary artery resistance, LV tissue redox dysregulation (i.e., increased PC levels) and detrimental remodeling (i.e., reduced inflammation), and reductions in ejection fraction (EF) and fractional shortening (FS) caused by PAH. The combination of treatments prevented reductions in EF and FS, along with the development of a D-shaped LV.

CONCLUSIONS

blueberry extract and moderate-intensity resistance training administered during the development of MCT-induced severe PAH in rats prevented LV redox dysregulation and pathological remodeling, thereby preserving its function.

Combined exercise hinders the progression of pulmonary and right heart harmful remodeling in monocrotaline-induced pulmonary arterial hypertension

The aim of this study was to test whether combined physical exercise training of moderate intensity executed during the development of monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH) hinders the progression of pulmonary and right heart harmful functional and structural remodeling in rats. Wistar rats were injected with MCT (60 mg/kg) and after 24 h were exposed to a combined exercise training program: aerobic exercise (treadmill running-60 min/day; 60% of maximum running speed); and resistance exercise (vertical ladder climbing-15 climbs; 60% of maximum carrying load), on alternate days, 5 days/wk, for ∼3 wk. After euthanasia, the lung and right ventricle (RV) were excised and processed for histological, single myocyte, and biochemical analyses. Combined exercise increased the tolerance to physical effort (time until fatigue and relative maximum load) and prevented increases in pulmonary artery resistance (acceleration time (TA)/ejection time (TE)] and reductions in RV function [tricuspid annular plane systolic excursion (TAPSE)]. Moreover, in myocytes isolated from the RV, combined exercise preserved contraction amplitude, as well as contraction and relaxation velocities, and inhibited reductions in the amplitude and maximum speeds to peak and to decay of the intracellular Ca2+ transient. Furthermore, combined exercise avoided RV (RV weight, cardiomyocyte, extracellular matrix, collagen, inflammatory infiltrate, and extracellular matrix) and lung (pulmonary alveoli and alveolar septum) harmful structural remodeling. In addition, combined exercise restricted RV [nitric oxide (NO) and carbonyl protein (CP)] and lung [catalase (CAT), glutathione S-transferase (GST), and NO] oxidative stress. In conclusion, the applied combined exercise regime hinders the progression of pulmonary and right heart functional and structural harmful remodeling in rats with MCT-induced PAH.NEW & NOTEWORTHY This study reveals that combined exercise improves tolerance to physical effort, prevents increases in pulmonary artery resistance, and conserves the right heart function during the progression of pulmonary arterial hypertension. Our analyses show that combined exercise hinders harmful right ventricular and lung structural remodeling and oxidative stress, which reflects in the maintenance of right ventricular myocytes' contractile function by preserving the intracellular calcium cycling. An attenuated progression of the disease impacts positively on its prognosis.

Study on the hypotensive effect and mechanism of hawthorn (Crataegus pinnatifida) fruits and hyperoside in spontaneously hypertensive rats

Hawthorn fruits have a sweet and sour taste, besides having beneficial therapeutic effects on hyperlipidemia, hypertension, and coronary heart disease, making them widely used in food and clinical medicine. However, their hypotensive effects and potential mechanisms of anti-hypertension still need to be elucidated. This study aims to explore the antihypertensive effect of hawthorn and its monomer hyperoside on spontaneously hypertensive rats through pharmacodynamics, serum metabolomics, and in vivo mechanism studies. After 7 weeks of intervention with hawthorn extract and hyperoside, the blood pressure was significantly reduced. Aortic vascular staining results showed that the injury was significantly improved after intervention with hawthorn extract and hyperoside. According to the serum metabolomics study, the main metabolic pathway regulating blood pressure in hawthorn extract and hyperoside groups was the primary bile acid biosynthesis pathway. Quantitative experiments confirmed that the level of bile acid in the model group was significantly different from that in the normal group, while that in the hawthorn group and the hyperoside group was close to that in the normal group. Based on the prediction of bile acid-hypertension related targets and the literature, nine genes involved in bile acid metabolism and inflammatory pathways were selected for further study. The FXR, TGR5, ET-1, NOS3, Akt1, TNF-α, Ptgs2, ACE2 and Kdr mRNA expression levels in the hawthorn extract and hyperoside groups were significantly different from those in the model groups. In summary, hawthorn extract and hyperoside have a hypotensive effect on spontaneously hypertensive rats through bile acid and inflammation related targets. Hence, hawthorn extract has the potential to become a functional food or an alternative therapy for hypertension.

Nanoemulsions and nanocapsules loaded with Melaleuca alternifolia essential oil for sepsis treatment

Sepsis represents a complex clinical syndrome that results from a harmful host response to infection. The infections most associated with sepsis are pneumonia, intra-abdominal infection, and urinary tract infection. Tea tree oil (TTO) has shown high antibacterial activity; however, it exhibits low aqueous solubility and high volatility, which have motivated its nanoencapsulation. In this study, the performance of nanoemulsions (NE) and nanocapsules (NC) loaded with TTO was compared. These systems were prepared by spontaneous emulsification and nanoprecipitation methods, respectively. Poly-ε-caprolactone or Eudragit® RS100 were tested as polymers for NCs whereas Tween® 80 or Pluronic® F68 as surfactants in NE preparation. Pluronic® F68 and Eudragit® RS100 resulted in more homogeneous and stable nanoparticles. In accelerated stability studies at 4 and 25 °C, both colloidal suspensions (NC and NE) were kinetically stable. NCs showed to be more stable to photodegradation and less cytotoxic than NEs. After sepsis induction by the cecal ligation and puncture (CLP) model, both NE and NC reduced neutrophil infiltration into peritoneal lavage (PL) and kidneys. Moreover, the systems increased group thiols in the kidney and lung tissue and reduced bacterial growth in PL. Taken together, both systems showed to be effective against injury induced by sepsis; however, NCs should be prioritized due to advantages in terms of cytotoxicity and physicochemical stability.

Effect of free and nanoemulsified β-caryophyllene on monocrotaline-induced pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is characterized by increased pulmonary vascular resistance (PVR), right ventricular (RV) failure and premature death. Compounds with vasodilatory characteristics, such as β-caryophyllene, could be promising therapeutics for PAH. This study aimed to determine the effects of free and nanoemulsified β-caryophyllene in lung oxidative stress and heart function in PAH rats. Male Wistar rats (170 g, n = 6/group) were divided into four groups: control (CO), monocrotaline (MCT), monocrotaline + β-caryophyllene (MCT-Bcar) and monocrotaline + nanoemulsion with β-caryophyllene (MCT-Nano). PAH was induced by MCT (60 mg/kg i.p.), and 7 days later, treatment with β-caryophyllene, either free or in a nanoemulsion (by gavage, 176 mg/kg/day) or vehicle was given for 14 days. Echocardiographic and hemodynamic measurements were performed, and after, the RV was collected for morphometry and the lungs for evaluation of oxidative stress, antioxidant enzymes, total sulfhydryl compounds, nitric oxide synthase (NOS) activity and endothelin-1 receptor expression. RV hypertrophy, increased PVR and RV systolic and diastolic pressures (RVSP and RVEDP, respectively) and increased mean pulmonary arterial pressure (mPAP) were observed in the MCT group. Treatment with both free and nanoemulsified β-caryophyllene reduced RV hypertrophy, mPAP, RVSP and lipid peroxidation. The reduction in RVSP was more pronounced in the MCT-Nano group. Moreover, RVEDP decreased only in the MCT-Nano group. These treatments also increased superoxide dismutase, catalase and NOS activities and decreased endothelin-1 receptors expression. Both β-caryophyllene formulations improved mPAP, PVR and oxidative stress parameters. However, β-caryophyllene in a nanoemulsion was more effective in attenuating the effects of PAH.

Activation of the p62-Keap1-Nrf2 pathway improves pulmonary arterial hypertension in MCT-induced rats by inhibiting autophagy

Autophagy is implicated in the pathogenesis of pulmonary arterial hypertension (PAH). We aimed to investigate whether the p62-Keap1-Nrf2 pathway affects the development of PAH by mediating autophagy. A PAH rat model was established using monocrotaline (MCT). Pulmonary artery smooth muscle cells (PASMCs) were extracted, and the changes in proliferation, migration, autophagy, and oxidative stress were analyzed following overexpression or knockdown of p62. The impact of p62 on the symptoms of PAH rats was assessed by the injection of an adenovirus overexpressing p62. We found that the knockdown of p62 increased the proliferation and migration of PASMCs, elevating the oxidative stress of PASMCs and upregulating gene expression of NADPH oxidases. Co-IP assay results demonstrated that p62 interacted with Keap1. p62 knockdown enhanced Keap1 protein stability and Nrf2 ubiquitination. LC3II/I and ATG5 were expressed more often when p62 was knocked down. Treating with an inhibitor of autophagy reversed the impact of p62 knockdown on PASMCs. Nrf2 inhibitor treatment reduced the expression of Nrf2 and p62, while increasing the expression of Keap1, LC3II/I, and ATG5 in PASMCs. However, overexpressing p62 diminished mRVP, SPAP, and Fulton index in PAH rats and attenuated pulmonary vascular wall thickening. Overexpression of p62 also decreased the expression of Keap1, LC3II/I, and ATG5 and increased the nuclear expression of Nrf2 in PAH rats. Importantly, overexpression of p62 reduced oxidative stress and the NADPH oxidase expression in PAH rats. Overall, activation of the p62-Keap1-Nrf2 positive feedback signaling axis reduces the proliferation and migration of PASMCs and alleviates PAH by inhibiting autophagy and oxidative stress.

Blueberry, cranberry, raspberry, and strawberry as modulators of the gut microbiota: target for treatment of gut dysbiosis in chronic kidney disease? From current evidence to future possibilities

Gut dysbiosis is common in patients with chronic kidney disease (CKD) and is associated with uremic toxin production, inflammation, oxidative stress, and cardiovascular disease development. Therefore, healthy dietary patterns are essential modulators of gut microbiota. In this context, studies suggest that consuming berry fruits, rich in polyphenols and nutrients, may positively affect the gut microbiota, promoting the selective growth of beneficial bacteria and improving clinical status. However, studies on the effects of berry fruits on gut microbiota in CKD are scarce, and a better understanding of the possible mechanisms of action of berry fruits on gut microbiota is needed to guide future clinical studies and clinical practice in CKD. The objective was to discuss how berry fruits (blueberry, cranberry, raspberry, and strawberry) could be a therapeutic strategy to modulate the gut microbiota and possibly reverse the dysbiosis in CKD. Overall, available evidence shows that berry fruits can promote an increase in diversity by affecting the abundance of mucus-producing bacteria and short-chain fatty acids. Moreover, these fruits can increase the expression of mRNA involved in tight junctions in the gut such as occludin, tight junction protein 1 (TJP1), and mucin. Studies on the exact amount of berries leading to these effects show heterogeneous findings. However, it is known that, with 5 mg/day, it is already possible to observe some effects in animal models. Wild berries could possibly improve the uremic condition by reducing the levels of uremic toxins via modulation of the gut microbiota. In the long term, this could be an excellent strategy for patients with CKD. Therefore, clinical studies are encouraged to evaluate better these effects on CKD as well as the safe amount of these fruits in order to promote a better quality of life or even the survival of these patients.

Unleashing the Potential of Nrf2: A Novel Therapeutic Target for Pulmonary Vascular Remodeling

Pulmonary vascular remodeling, characterized by the thickening of all three layers of the blood vessel wall, plays a central role in the pathogenesis of pulmonary hypertension (PH). Despite the approval of several drugs for PH treatment, their long-term therapeutic effect remains unsatisfactory, as they mainly focus on vasodilation rather than addressing vascular remodeling. Therefore, there is an urgent need for novel therapeutic targets in the treatment of PH. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a vital transcription factor that regulates endogenous antioxidant defense and emerges as a novel regulator of pulmonary vascular remodeling. Growing evidence has suggested an involvement of Nrf2 and its downstream transcriptional target in the process of pulmonary vascular remodeling. Pharmacologically targeting Nrf2 has demonstrated beneficial effects in various diseases, and several Nrf2 inducers are currently undergoing clinical trials. However, the exact potential and mechanism of Nrf2 as a therapeutic target in PH remain unknown. Thus, this review article aims to comprehensively explore the role and mechanism of Nrf2 in pulmonary vascular remodeling associated with PH. Additionally, we provide a summary of Nrf2 inducers that have shown therapeutic potential in addressing the underlying vascular remodeling processes in PH. Although Nrf2-related therapies hold great promise, further research is necessary before their clinical implementation can be fully realized.

Nuts and berries from agroforestry systems in temperate regions can form the foundation for a healthier human diet and improved outcomes from diet-related diseases

Agroforestry is a specific type of agroecosystem that includes trees and shrubs with the potential to yield nutrient-rich products that contribute to human health. This paper reviews the literature on the human health benefits of tree nut and berry species commonly associated with agroforestry systems of the United States, considering their potential for preventing certain diet-related diseases. Emphasis is placed on those diseases that are most closely associated with poor outcomes from COVID-19, as they are indicators of confounding health prognoses. Results indicate that tree nuts reduce the risk of coronary heart disease, and walnuts (Juglans species) are particularly effective because of their unique fatty acid profile. Berries that are grown on shrubs have the potential to contribute to mitigation of hypertension, prevention of Type II diabetes, and reduced risk of cardiovascular disease. To optimize human health benefits, plant breeding programs can focus on the traits that enhance the naturally-occurring phytochemicals, through biofortification. Value-added processing techniques should be selected and employed to preserve the phytonutrients, so they are maintained through the point of consumption. Agroforestry systems can offer valuable human health outcomes for common diet-related diseases, in addition to providing many environmental benefits, particularly if they are purposefully designed with that goal in mind. The food system policies in the U.S. might be reoriented to prioritize these food production systems based on the health benefits.

Activation of PPAR-γ prevents TERT-mediated pulmonary vascular remodeling in MCT-induced pulmonary hypertension

Background

It has been demonstrated that elevated telomerase reverse transcriptase (TERT) expression or activity is implicated in pulmonary hypertension (PH). In addition, activation of peroxisome-proliferator-activated receptor γ (PPAR-γ) has been found to prevent PH progression. However, the molecular mechanism responsible for the protective effect of PPAR-γ activation on TERT expression in the pathogenesis of PH remains unknown. This study was performed to address these issues.

Methods

Intraperitoneal injection of monocrotaline (MCT) was used to establish PH. BIBR1532 was applied to inhibit the activity of telomerase. The right ventricular systolic pressure (RVSP) and histological analysis were used to detect the development of PH. The protein levels of p-Akt, t-Akt, c-Myc and TERT were determined by western blotting. Pharmacological inhibition of TERT by BIBR1532 effectively suppressed RVSP, RVHI and the WT% in MCT-induced PH rats.

Results

Pharmacological inhibition of Akt/c-Myc pathway by LY294002 diminished TERT upregulation, RVSP, RVHI and WT% in MCT-PH rats. Activation of PPAR-γ by pioglitazone inhibited p-Akt and c-Myc expressions and further downregulated TERT, thus to reduced RVSP, RVHI and WT% in MCT-treated PH rats.

Conclusions

In conclusion, TERT upregulation contributes to PH development in MCT-treated rats. Activation of PPAR-γ prevents pulmonary arterial remodeling through Akt/c-Myc/TERT axis suppression.

Behind the Scenes of Anthocyanins-From the Health Benefits to Potential Applications in Food, Pharmaceutical and Cosmetic Fields

Anthocyanins are widespread and biologically active water-soluble phenolic pigments responsible for a wide range of vivid colours, from red (acidic conditions) to purplish blue (basic conditions), present in fruits, vegetables, and coloured grains. The pigments' stability and colours are influenced mainly by pH but also by structure, temperature, and light. The colour-stabilizing mechanisms of plants are determined by inter- and intramolecular co-pigmentation and metal complexation, driven by van der Waals, π-π stacking, hydrogen bonding, and metal-ligand interactions. This group of flavonoids is well-known to have potent anti-inflammatory and antioxidant effects, which explains the biological effects associated with them. Therefore, this review provides an overview of the role of anthocyanins as natural colorants, showing they are less harmful than conventional colorants, with several technological potential applications in different industrial fields, namely in the textile and food industries, as well as in the development of photosensitizers for dye-sensitized solar cells, as new photosensitizers in photodynamic therapy, pharmaceuticals, and in the cosmetic industry, mainly on the formulation of skin care formulations, sunscreen filters, nail colorants, skin & hair cleansing products, amongst others. In addition, we will unveil some of the latest studies about the health benefits of anthocyanins, mainly focusing on the protection against the most prevalent human diseases mediated by oxidative stress, namely cardiovascular and neurodegenerative diseases, cancer, and diabetes. The contribution of anthocyanins to visual health is also very relevant and will be briefly explored.

Exercise training decreases oxidative stress in skeletal muscle of rats with pulmonary arterial hypertension

The effects of exercise training on oxidative stress in gastrocnemius of rats with pulmonary hypertension were studied. Four groups were established: sedentary control (SC), sedentary monocrotaline (SM), trained control (TC), trained monocrotaline (TM). Exercise was applied for 4 weeks, 5 days/week, 50-60 min/session, at 60% of VO₂ max. Right ventricular (RV) pressures were measured, heart and gastrocnemius were removed for morphometric/biochemical analysis. Lipid peroxidation (LPO), H₂O₂, GSH/GSSG, and activity/expression of antioxidant enzymes were evaluated. Increased RV hypertrophy, systolic and end-diastolic pressures (RVEDP) were observed in SM animals, and the RVEDP was decreased in TM vs. SM. H₂O₂, SOD-1, and LPO were higher in the SM group than in SC. In TM, H₂O₂ was further increased when compared to SM, with a rise in antioxidant defences and a decrease in LPO. GSH/GSSG was higher only in the TC group. Exercise induced an efficient antioxidant adaptation, preventing oxidative damage to lipids.

Oxidative Stress and Antioxidative Therapy in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is clinically characterized by a progressive increase in pulmonary artery pressure, followed by right ventricular hypertrophy and subsequently right heart failure. The underlying mechanism of PAH includes endothelial dysfunction and intimal smooth muscle proliferation. Numerous studies have shown that oxidative stress is critical in the pathophysiology of PAH and involves changes in reactive oxygen species (ROS), reactive nitrogen (RNS), and nitric oxide (NO) signaling pathways. Disrupted ROS and NO signaling pathways cause the proliferation of pulmonary arterial endothelial cells (PAECs) and pulmonary vascular smooth muscle cells (PASMCs), resulting in DNA damage, metabolic abnormalities, and vascular remodeling. Antioxidant treatment has become a main area of research for the treatment of PAH. This review mainly introduces oxidative stress in the pathogenesis of PAH and antioxidative therapies and explains why targeting oxidative stress is a valid strategy for PAH treatment.

Target Nuclear Factor Erythroid 2-Related Factor 2 in Pulmonary Hypertension: Molecular Insight into Application

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a key transcription factor involved in maintaining redox balance and activates the expression of downstream antioxidant enzymes. Nrf2 has received wide attention considering its crucial role in oxidative and electrophilic stress. Large amounts of studies have demonstrated the protective role of Nrf2 activation in various pulmonary hypertension (pH) models. Additionally, various kinds of natural phytochemicals acting as Nrf2 activators prevent the development of pH and provide a novel and promising therapeutic insight for the treatment of pH. In the current review, we give a brief introduction of Nrf2 and focus on the role and mechanism of Nrf2 in the pathophysiology of pH and then review the relevant research of Nrf2 agonists in pH in both experimental research and clinical trials.

Dan-Shen-Yin Granules Prevent Hypoxia-Induced Pulmonary Hypertension via STAT3/HIF-1α/VEGF and FAK/AKT Signaling Pathways

Traditional Chinese medicine (TCM) plays an important role in the treatment of complex diseases, especially cardiovascular diseases. However, it is hard to identify their modes of action on account of their multiple components. The present study aims to evaluate the effects of Dan-Shen-Yin (DSY) granules on hypoxia-induced pulmonary hypertension (HPH), and then to decipher the molecular mechanisms of DSY. Systematic pharmacology was employed to identify the targets of DSY on HPH. Furthermore, core genes were identified by constructing a protein-protein interaction (PPI) network and analyzed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes (KEGG) analysis. Related genes and pathways were verified using a hypoxia-induced mouse model and hypoxia-treated pulmonary artery cells. Based on network pharmacology, 147 potential targets of DSY on HPH were found, constructing a PPI network, and 13 hub genes were predicted. The results showed that the effect of DSY may be closely associated with AKT serine/threonine kinase 1 (AKT1), signal transducer and activator of transcription 3 (STAT3), and HIF-1 signaling pathways, as well as biological processes such as cell proliferation. Consistent with network pharmacology analysis, experiments in vivo demonstrated that DSY could prevent the development of HPH in a hypoxia-induced mouse model and alleviate pulmonary vascular remodeling. In addition, inhibition of STAT3/HIF-1α/VEGF and FAK/AKT signaling pathways might serve as mechanisms. Taken together, the network pharmacology analysis suggested that DSY exhibited therapeutic effects through multiple targets in the treatment of HPH. The inferences were initially confirmed by subsequent in vivo and in vitro studies. This study provides a novel perspective for studying the relevance of TCM and disease processes and illustrates the advantage of this approach and the multitargeted anti-HPH effect of DSY.

Chronic Sigma 1 receptor activation alleviates right ventricular dysfunction secondary to pulmonary arterial hypertension

Sigma 1 receptor (S1R) has shown a preferable protective effect on left ventricular function, but whether it protects right ventricular (RV) function is still elusive.This study aimed to determine the effects of S1R on RV dysfunction secondary to pulmonary arterial hypertension.Sixty wild-type male Sprague–Dawley rats were randomly divided into the control group, the fluvoxamine group, the pulmonary arterial hypertension group and the pulmonary arterial hypertension combined with fluvoxamine group. Monocrotaline (60 mg/kg) was administered to induce pulmonary arterial hypertension, and fluvoxamine was given for 21 consecutive days to activate S1R after one week of monocrotaline administration. Echocardiographic, serologic, and histologic parameters, qRT-PCR, and western blotting were conducted after 4 weeks of monocrotaline administration.The expression of S1R was decreased in the right ventricle in pulmonary arterial hypertension. TAPSE, and the FAC of the right ventricle were significantly decreased, and RV EDP and the plasma concentration of N-terminal pro-B-type natriuretic peptide was increased in the pulmonary arterial hypertension group, but fluvoxamine partly restored those abnormalities (all P < 0.05). Moreover, pulmonary arteriole remodeling, and fibrosis and hypertrophy in the RV were shown in the pulmonary arterial hypertension group; interestingly, fluvoxamine recovered RV structural remodeling (all P < 0.05) but neither alleviated pulmonary arteriole remodeling nor reduced pulmonary artery pressure. Furthermore, S1R activation protects RV function by upgrading the NRF 2/HO 1-mediated antioxidant stress pathway. In conclusion, chronic S1R activation ameliorates structural remodeling and RV dysfunction secondary to pulmonary arterial hypertension without altering pulmonary artery pressure.

Melatonin Attenuates Dasatinib-Aggravated Hypoxic Pulmonary Hypertension via Inhibiting Pulmonary Vascular Remodeling

Dasatinib treatment is approved as first-line therapy for chronic myeloid leukemia. However, pulmonary hypertension (PH) is a highly morbid and often fatal side-effect of dasatinib, characterized by progressive pulmonary vascular remodeling. Melatonin exerts strong antioxidant capacity against the progression of cardiovascular system diseases. The present work aimed to investigate the effect of melatonin on dasatinib-aggravated hypoxic PH and explore its possible mechanisms. Dasatinib-aggravated rat experimental model of hypoxic PH was established by utilizing dasatinib under hypoxia. The results indicated that melatonin could attenuate dasatinib-aggravated pulmonary pressure and vascular remodeling in rats under hypoxia. Additionally, melatonin attenuated the activity of XO, the content of MDA, the expression of NOX4, and elevated the activity of CAT, GPx, and SOD, the expression of SOD2, which were caused by dasatinib under hypoxia. In vitro, dasatinib led to decreased LDH activity and production of NO in human pulmonary microvascular endothelial cells (HPMECs), moreover increased generation of ROS, and expression of NOX4 both in HPMECs and primary rat pulmonary arterial smooth muscle cells (PASMCs) under hypoxia. Dasatinib up-regulated the expression of cleaved caspase-3 and the ratio of apoptotic cells in HPMECs, and also elevated the percentage of S phase and the expression of Cyclin D1 in primary PASMCs under hypoxia. Melatonin ameliorated dasatinib-aggravated oxidative damage and apoptosis in HPMECs, meanwhile reduced oxidative stress level, proliferation, and repressed the stability of HIF1-α protein in PASMCs under hypoxia. In conclusion, melatonin significantly attenuates dasatinib-aggravated hypoxic PH by inhibiting pulmonary vascular remodeling in rats. The possible mechanisms involved protecting endothelial cells and inhibiting abnormal proliferation of smooth muscle cells. Our findings may suggest that melatonin has potential clinical value as a therapeutic approach to alleviate dasatinib-aggravated hypoxic PH.

Blueberry extract improves redox balance and functional parameters in the right ventricle from rats with pulmonary arterial hypertension

PURPOSE

Pulmonary arterial hypertension (PAH) is a disease characterized by increased pulmonary vascular resistance and right ventricle (RV) failure. In this context, oxidative stress is an essential element contributing to PAH's pathophysiology. Thus, blueberry (BB), which has a high antioxidant capacity, emerges as a natural therapeutic approach in PAH. This work evaluated the effect of BB extract on redox balance in RV in a PAH's animal model.

METHODS

Male Wistar rats (200 ± 20 g) (n = 72) were randomized into eight groups: control (CTR); monocrotaline (MCT); CTR and MCT treated at doses of 50, 100, and 200 mg/kg BB. PAH was induced by administration of MCT (60 mg/kg, intraperitoneal). Rats were treated with BB orally for 5 weeks (2 weeks before monocrotaline and 3 weeks after monocrotaline injection). On day 35, rats were submitted to echocardiography and catheterization, then euthanasia and RV harvesting for biochemical analyses.

RESULTS

RV hypertrophy, observed in the MCT groups, was reduced with BB treatment. MCT elevated RV systolic pressure and pressure/time derivatives, while the intervention with BB decreased these parameters. PAH decreased RV output and pulmonary artery outflow acceleration/ejection time ratio, while increased RV diameters, parameters restored by BB treatment. Animals from the MCT group showed elevated lipid peroxidation and NADPH oxidase activity, outcomes attenuated in animals treated with BB, which also led to increased catalase activity.

CONCLUSION

Treatment with BB partially mitigated PAH, which could be associated with improvement of RV redox state. Such findings constitute an advance in the investigation of the role of BB extract in chronic progressive cardiovascular diseases that involve the redox balance, such as PAH.

Effect of Flavonoids in Hawthorn and Vitamin C Prevents Hypertension in Rats Induced by Heat Exposure

Background: Excessive oxidative stress is associated with hypertension in professional high-temperature working conditions. Polyphenols exhibit a cardioprotective effect. Hawthorn contains high amounts of flavonoids, though its effect on hypertension protection has yet to be studied. This study aims to investigate this effect of extract of hawthorn (EH) or its combination with vitamin C (Vit. C) in rats induced by working under a hot environment. Methods: Forty-two male rats were randomly divided into a control group under normal temperature and six treatment groups exposed at 33 ± 1 °C along with 1 h of daily treadmill running. They were orally provided with water, Vit. C (14mg/kg), EH (125, 250, and 500 mg/kg), and EH500 + Vit. C, once a day for four weeks. Results: Both EH and Vit. C alone reduced the systolic and diastolic blood pressure of rats exposed to the heat environment; however, their joint supplementation completely maintained their blood pressure to the normal level throughout the experimental period. No morphological changes were found on the intima of aorta. Moreover, the co-supplementation of EH and Vit. C prevented the changes of heat exposure in inducing oxidative stress markers, such as glutathione peroxidase, catalase, total antioxidant capacity, and nitric oxide; the synergistic action was more effective than either individual treatment of EH and Vit. C. Furthermore, the administration of EH had more potent effects on increasing superoxide dismutase, IL-2, the 70 kilodalton heat shock proteins and high sensitivity C reactive protein, and decreasing serum malondialdehyde and lipofuscin in vascular tissue than those in Vit. C group. Conclusions: A strong synergistic effect of EH and Vit. C on the prevention of hypertension under heat exposure was established, as they inhibited the oxidative stress state. This study also sets up a novel intervention strategy in animal models for investigation on the early phases of hypertension induced by heat exposure.

Bioactivities and mechanisms of natural medicines in the management of pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a progressive and rare disease without obvious clinical symptoms that shares characteristics with pulmonary vascular remodeling. Right heart failure in the terminal phase of PAH seriously threatens the lives of patients. This review attempts to comprehensively outline the current state of knowledge on PAH its pathology, pathogenesis, natural medicines therapy, mechanisms and clinical studies to provide potential treatment strategies. Although PAH and pulmonary hypertension have similar pathological features, PAH exhibits significantly elevated pulmonary vascular resistance caused by vascular stenosis and occlusion. Currently, the pathogenesis of PAH is thought to involve multiple factors, primarily including genetic/epigenetic factors, vascular cellular dysregulation, metabolic dysfunction, even inflammation and immunization. Yet many issues regarding PAH need to be clarified, such as the "oestrogen paradox". About 25 kinds monomers derived from natural medicine have been verified to protect against to PAH via modulating BMPR2/Smad, HIF-1α, PI3K/Akt/mTOR and eNOS/NO/cGMP signalling pathways. Yet limited and single PAH animal models may not corroborate the efficacy of natural medicines, and those natural compounds how to regulate crucial genes, proteins and even microRNA and lncRNA still need to put great attention. Additionally, pharmacokinetic studies and safety evaluation of natural medicines for the treatment of PAH should be undertaken in future studies. Meanwhile, methods for validating the efficacy of natural drugs in multiple PAH animal models and precise clinical design are also urgently needed to promote advances in PAH.

Blueberry extract attenuates norepinephrine-induced oxidative stress and apoptosis in H9c2 cardiac cells

Enhanced sympathetic system activation mediated by norepinephrine (NE) contributes to adverse cardiac remodeling leading to oxidative stress and cell death, progressing to heart failure. Natural antioxidants may help maintain redox balance, attenuating NE-mediated cardiac cell damage. In the present study, we evaluated the effect of a blueberry extract (BBE) on H9c2 cardiac cells exposed to NE on cell death, oxidative stress status and its major signaling pathways. H9c2 cells were pre-incubated with 50 μg/ml of BBE for 4 h and maintained in the presence of 100 μM NE for 24 h. NE exposure resulted in increased caspase 3/7 activity. This was associated with reduced protein expression of antioxidants catalase, superoxide dismutase and glutathione peroxidase and increase in 4-hydroxynonenal adduct formation. NE led to increased activity of Protein kinase B (Akt), Forkhead box O3a and AMP-activated protein kinase alpha and decreased activity of Signal transducer and activator of transcription 3. BBE prevented caspases activation and abrogated NE-induced increase in oxidative stress, as well as attenuated the increase in Akt. Based on these findings, it is concluded that BBE promoted cardioprotection of H9c2 cells in an in vitro model of NE-induced oxidative damage, suggesting a cardioprotective role for BBE in response to NE exposure.

Thioredoxin system activation is associated with the progression of experimental pulmonary arterial hypertension

In addition to being an antioxidant, thioredoxin (Trx) is known to stimulate signaling pathways involved in cell proliferation and to inhibit apoptosis. The aim of this study was to explore the role of Trx in some of these pathways along the progression of monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH). Male rats were first divided into two groups: monocrotaline (MCT - 60 mg/kg i.p.) and control (received saline), that were further divided into three groups: 1, 2, and 3 weeks. Animals were submitted to echocardiographic analysis. Right and left ventricles were used for the measurement of hypertrophy, through morphometric and histological analysis. The lung was prepared for biochemical and molecular analysis. One week after MCT injection, there was an increase in thioredoxin reductase (TrxR) activity, a reduction in glutathione reductase (GR) activity, and an increase in Trx-1 and vitamin D3 up-regulated protein-1 (VDUP-1) expression. Two weeks after MCT injection, there was an increase in VDUP-1, Akt and cleaved caspase-3 activation, and a decrease in Trx-1 and Nrf2 expression. PAH-induced by MCT promoted a reduction in Nrf2 and Trx-1 expression as well as an increase in Akt and VDUP-1 expression after three weeks. The increase in pulmonary vascular resistance was accompanied by increased TrxR activity, suggesting an association between the Trx system and functional changes in the progression of PAH. It seems that Trx-1 activation was an adaptive response to MCT administration to cope with pulmonary remodeling and disease progression, suggesting a potential new target for PAH therapeutics.

Pulmonary arterial hypertension induces the release of circulating extracellular vesicles with oxidative content and alters redox and mitochondrial homeostasis in the brains of rats

Pulmonary arterial hypertension (PAH) is characterized by increased resistance of the pulmonary vasculature and afterload imposed on the right ventricle (RV). Two major contributors to the worsening of this disease are oxidative stress and mitochondrial impairment. This study aimed to explore the effects of monocrotaline (MCT)-induced PAH on redox and mitochondrial homeostasis in the RV and brain and how circulating extracellular vesicle (EV) signaling is related to these phenomena. Wistar rats were divided into control and MCT groups (60 mg/kg, intraperitoneal), and EVs were isolated from blood on the day of euthanasia (21 days after MCT injections). There was an oxidative imbalance in the RV, brain, and EVs of MCT rats. PAH impaired mitochondrial function in the RV, as seen by a decrease in the activities of mitochondrial complex II and citrate synthase and manganese superoxide dismutase (MnSOD) protein expression, but this function was preserved in the brain. The key regulators of mitochondrial biogenesis, namely, proliferator-activated receptor gamma coactivator 1-alpha and sirtuin 1, were poorly expressed in the EVs of MCT rats, and this result was positively correlated with MnSOD expression in the RV and negatively correlated with MnSOD expression in the brain. Based on these findings, we can conclude that the RV is severely impacted by the development of PAH, but this pathological injury may signal the release of circulating EVs that communicate with different organs, such as the brain, helping to prevent further damage through the upregulation of proteins involved in redox and mitochondrial function.

Aquatic exercise associated or not with grape juice consumption-modulated oxidative parameters in Parkinson disease patients: A randomized intervention study

Parkinson's disease (PD) is a neurodegenerative disorder with significant motor disabilities and cognitive decline. Importantly, the imbalance of oxidative stress is related to PD physiopathology and progression. This study aimed to evaluate the impact of grape juice consumption associated with an aquatic exercise protocol on oxidative stress parameters and cognitive function in individuals with PD. The participants were randomized into two groups: grape juice group (GJG) and control group (CG) and were submitted to 4 weeks of an aquatic intervention (twice a week, approximately 60 minutes/session). The GJG also consumed 400 ml of grape juice per day (integral and conventional) during this period. Cognitive function was assessed by the Montreal Cognitive Assessment (MoCa) questionnaire. For the analysis of oxidative stress markers, specifically lipid oxidative damage (TBARS), proteins (Carbonil), acid uric and the activity of antioxidant enzymes (superoxide dismutase, glutathione peroxidase and catalase), blood collection were done before and after intervention. No changes were observed in cognitive function after intervention in both groups. Regarding biomarkers, a reduction of antioxidant enzymes, thiobarbituric acid reactive substances (TBARS) and uric acid was observed in both groups. However, only the GJG showed a significant reduction on protein oxidation levels after intervention. In conclusion, the consumption of grape juice associated with an aquatic exercise protocol might be consider an effective alternative to reduce the oxidative damage in PD, reinforcing the importance of this intervention in promoting beneficial impact in this population.

Beneficial Effects of Spirulina Aqueous Extract on Vasodilator Function of Arteries from Hypertensive Rats

Hypertension is a multifactorial disorder considered one of the major causes of premature death worldwide. This pathology is associated with vascular functional/structural alterations in which nitric oxide (NO) and oxygen reactive species participate. On the other hand, the use of microalgae extracts in the treatment of cardiovascular diseases is increasing. Based on the antioxidant and antihypertensive properties of Spirulina, this study aims to investigate the effect of an aqueous extract of Spirulina on the vasodilator function of the aorta from spontaneously hypertensive rats (SHR), analyzing the functional role of NO. For this, aortic segments from male SHR were divided into two groups, one control and the other exposed to an Spirulina aqueous extract (0.1% w/v, for 3 hours), to analyze (i) the production of NO, superoxide anion, and hydrogen peroxide; (ii) the vasodilator response induced by acetylcholine (ACh), by the NO donor and sodium nitroprusside (SNP), and by the KATP channel opener and pinacidil; and (iii) the expression of the p-Akt, p-eNOS, and HO-1 proteins. The results showed that the aqueous Spirulina extract (i) increased the production of NO, did not significantly modify that of superoxide, while decreased that of hydrogen peroxide; (ii) increased the vasodilatory responses induced by ACh, NPS, and pinacidil; and (iii) increased the expression of p-Akt and HO-1. These results suggest that incubation with the aqueous Spirulina extract improves the vascular function of arteries from SHR by increasing the release/bioavailability/function of NO. Increased KATP channel activation and expression of pAkt and HO-1 appear to be participating in these actions.

Optimization of a Novel Method Based on Ultrasound-Assisted Extraction for the Quantification of Anthocyanins and Total Phenolic Compounds in Blueberry Samples (Vaccinium corymbosum L.)

In recent years, consumers' preference for fruits such as blueberry has increased noticeably. This fact is probably related to their bioactive components such as anthocyanins, phenolic compounds, vitamins, minerals, and tannins that have been found in blueberries by the latest research studies. Both total anthocyanins (TA) and total phenolic compounds (TPC) are known for their multiple beneficial effects on our health, due to their anti-inflammatory, anti-oxidant, and anti-cancer properties. This is the reason why the development of new methodologies for the quality control analysis of raw materials or derived products from blueberry has a great relevance. Two ultrasound-assisted extraction methods (UAE) have been optimized for the quantification of TA and TPC in blueberry samples. The six variables to be optimized were: solvent composition, temperature, amplitude, cycle, extraction solvent pH, and sample/solvent ratio using response surface methodology. The optimized methods have proven to be suitable for the extraction of the TPC and TA with good precision (repeatability and intermediate precision) (coefficient of variation (CV) < 5%) and potentially for application in commercial samples. This fact, together with the multiple advantages of UAE, makes these methods a good alternative to be used in quality control analysis by both industries and laboratories.

Nutraceuticals in the Treatment of Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a severe disease characterized by the loss and obstructive remodeling of the pulmonary arterial wall, causing a rise in pulmonary arterial pressure and pulmonary vascular resistance, which is responsible for right heart failure, functional decline, and death. Although many drugs are available for the treatment of this condition, it continues to be life-threatening, and its long-term treatment is expensive. On the other hand, many natural compounds present in food have beneficial effects on several cardiovascular conditions. Several studies have explored many of the potential beneficial effects of natural plant products on PAH. However, the mechanisms by which natural products, such as nutraceuticals, exert protective and therapeutic effects on PAH are not fully understood. In this review, we analyze the current knowledge on nutraceuticals and their potential use in the protection and treatment of PAH, as well as whether nutraceuticals could enhance the effects of drugs used in PAH through similar mechanisms.