Punicalagin Prevents Hypoxic Pulmonary Hypertension via Anti-Oxidant Effects in Rats

Pomegranate (Punica granatum L.) phytochemicals target the components of metabolic syndrome

Pomegranate (Punica granatum L.) is a multipurpose dietary and medicinal plant known for its ability to promote various health benefits. Metabolic syndrome (MetS) is a complex metabolic disorder driving health and socioeconomic challenges worldwide. It may be characterized by insulin resistance, abdominal obesity, hypertension, and dyslipidemia. This study aims to conduct a review of pomegranate's effects on MetS parameters using a mechanistic approach relying on pre-clinical studies. The peel, juice, roots, bark, seeds, flowers, and leaves of the fruit present several bioactive compounds that are related mainly to anti-inflammatory and antioxidant activities as well as cardioprotective, antidiabetic, and antiobesity effects. The use of the juice extract can work as a potent inhibitor of angiotensin-converting enzyme activities, consequently regulating blood pressure. The major bioactive compounds found within the fruit are phenolic compounds (hydrolysable tannins and flavonoids) and fatty acids. Alkaloids, punicalagin, ellagitannins, ellagic acid, anthocyanins, tannins, flavonoids, luteolin, and punicic acid are also present. The antihyperglycemia, antihyperlipidemia, and weight loss promoting effects are likely related to the anti-inflammatory and antioxidant effects. When considering clinical application, pomegranate extracts are found to be frequently well-tolerated, further supporting its efficacy as a treatment modality. We suggest that pomegranate fruit, extract, or processed products can be used to counteract MetS-related risk factors. This review represents an important step towards exploring potential avenues for further research in this area.

Oral administration of punicalagin attenuates imiquimod-induced psoriasis by reducing ROS generation and inflammation via MAPK/ERK and NF-κB signaling pathways

Psoriasis, an immune-mediated chronic inflammatory skin disease, imposes a huge mental and physical burden on patients and severely affects their quality of life. Punicalagin (PU), the most abundant ellagitannin in pomegranates, has become a research hotspot owing to its diverse biological activities. However, its effects on psoriasis remain unclear. We explored the impact and molecular mechanism of PU on M5-stimulated keratinocyte cell lines and imiquimod (IMQ)-induced psoriasis-like skin inflammation in BABL/c mice using western blotting, quantitative real-time polymerase chain reaction (qRT-PCR), hematoxylin and eosin (H&E) stain, immunohistochemistry, and immunofluorescent. Administration of PU-enriched pomegranate extract at dosages of 150 and 250 mg/kg/day markedly attenuated psoriatic severity, abrogated splenomegaly, and reduced IMQ-induced abnormal epidermal proliferation, CD4+ T-cell infiltration, and inflammatory factor expression. Moreover, PU could decrease expression levels of pro-inflammatory cytokines, such as IL-1β, IL-1α, IL-6, IL-8, TNF-α, IL-17A, IL-22, IL-23A, and reactive oxygen species (ROS), followed by keratinocyte proliferation inhibition in the M5-stimulated cell line model of inflammation through inhibition of mitogen-activated protein kinases/extracellular regulated protein kinases (MAPK/ERK) and nuclear factor kappaB (NF-κB) signaling pathways. Our results indicate that PU may serve as a promising nutritional intervention for psoriasis by ameliorating cellular oxidative stress and inflammation.

Natural compounds targeting mitochondrial dysfunction: emerging therapeutics for target organ damage in hypertension

Hypertension generally causes target organ damage (TOD) in the heart, brain, kidney, and blood vessels. This can result in atherosclerosis, plaque formation, cardiovascular and cerebrovascular events, and renal failure. Recent studies have indicated that mitochondrial dysfunction is crucial in hypertensive target organ damage. Consequently, mitochondria-targeted therapies attract increasing attention. Natural compounds are valuable resources for drug discovery and development. Many studies have demonstrated that natural compounds can ameliorate mitochondrial dysfunction in hypertensive target organ damage. This review examines the contribution of mitochondrial dysfunction to the development of target organ damage in hypertension. Moreover, it summarizes therapeutic strategies based on natural compounds that target mitochondrial dysfunction, which may be beneficial for preventing and treating hypertensive target organ damage.

Punica granatum L. Extract Shows Cardioprotective Effects Measured by Oxidative Stress Markers and Biomarkers of Heart Failure in an Animal Model of Metabolic Syndrome

Metabolic syndrome (MetS) significantly increases the risk of cardiovascular diseases (CVD), a leading cause of death globally. The presented study investigated the cardioprotective role of dietary polyphenols found in pomegranate peels in an animal model of metabolic syndrome. Zucker diabetic fatty rats (ZDF, MetS rats, fa/fa) were supplemented with polyphenol-rich pomegranate peel extract (EPP) at two dosages: 100 mg/kg BW and 200 mg/kg BW. The extract was administered for 8 weeks. The effect of ethanolic peel extract on the concentration of oxidative stress markers (CAT, SOD, MnSOD, GR, GST, GPx, TOS, SH, and MDA), biomarkers of heart failure (cTnI, GAL-3), and alternations in tissue architecture was assessed. The results showed a significant increase in SH concentration mediated via EPP supplementation (p < 0.001). Treatment with a 100 mg/kg BW dosage reduced the TOS level more efficiently than the higher dose. Interestingly, the CAT and GST activities were relevantly higher in the MetS 100 group (p < 0.001) compared to the MetS control. The rats administered EPP at a dose of 200 mg/kg BW did not follow a similar trend. No differences in the GR (p = 0.063), SOD (p = 0.455), MnSOD (p = 0.155), and MDA (p = 0.790) concentration were observed after exposure to the pomegranate peel extract. The administration of EPP did not influence the cTnI and GAL-3 levels. Histology analysis of the heart and aorta sections revealed no toxic changes in phenolic-treated rats. The findings of this study prove that the extract from pomegranate peels possesses free radical scavenging properties in the myocardium. The effect on alleviating ventricular remodeling and cardiomyocyte necrosis was not confirmed and requires further investigation.

Pomegranate Peel in the Amelioration of High-Altitude Disease: A Network Pharmacology and Molecular Docking Study of Underlying Mechanisms

High-altitude disease (HAD) describes the failure to adapt to the lack of oxygen found at high altitudes and therapeutic antioxidant effects have been attributed to pomegranate peel (PP) extract. Network pharmacology, molecular docking, and experimental validation were used to study mechanisms responsible for the alleviation of HAD by PP. The aim was to establish a reference for future research and aid technological development, particularly in clinical settings. Network pharmacology analysis showed that PP affected many targets in HAD via the active ingredients, luteolin 7-O-glycoside, punicalagin, and ellagic acid. HNRNPA1, HSPA1B, HSPA1A, CUL4B, CLTC, PPP1CA, PARP1, RACK1, NEDD8, and MAP3K1 were all targets, responsible for effects on ribosomes, apoptosis, cell cycle, mRNA surveillance pathway, and the MAPK signaling pathway. PP had an antiapoptosis effect on H9c2 cells damaged by hypoxia, as shown by annexinV-FITC/PI double staining. Practical Applications. HAD comprises a group of diseases caused by failure to adapt to a low-oxygen environment. PP extract has previously been shown to have antioxidant effects. PP attenuated damage to H9c2 cells and reduced the apoptosis rate. The current results lay the foundation for further experimental investigations.

Reversal of NADPH Oxidase-Dependent Early Oxidative and Inflammatory Responses in Chronic Obstructive Pulmonary Disease by Puerarin

In the present study, we investigated effects of Puerarin on the early oxidative and inflammatory responses in the lung triggered by acute cigarette smoking (ACS). C57BL/6 mice were exposed to ACS for 1 hr in the presence or absence of Puerarin and harvested at 2, 6, and 24 hours. ACS induced significant increases in superoxide production in mouse lungs at 2 and 6 hours; and superoxide production was also elevated in a time and concentration dependent manner in cigarette smoke extract (CSE) stimulated human small airway epithelial cells (HSAECs), which was dose-dependently abrogated by Puerarin. ACS exposure upregulated NOX1, NOX2, and NOX4 protein expression in mouse lungs. Likewise, NOX1 and NOX4 were upregulated in CSE-stimulated HSAECs. These responses were significantly or completely attenuated by Puerarin. ACS induced significant infiltrations of neutrophils and macrophages in mouse lung parenchyma and BAL fluid, which were completely or significantly abrogated by Puerarin, so was the activation of the NF-кB pathway and the upregulation in inflammatory mediators including TNF-α, KC (murine homolog of IL-8), COX-2, IL-6 and MCP-1. Nuclear translocation of p65, IL-8 secretion, and upregulation of COX-2 in CSE stimulated HSAECs were also markedly attenuated by Puerarin. Moreover, ACS or CSE stimulated upregulation in reactive oxygen species (ROS) production and expression of inflammatory mediators were alleviated by ROS scavenger TEMPO in vivo and vitro, with no synergy combining with Puerarin, indicating that the effects of Puerarin are redox-sensitive following activation of NOX. In summary, our data for the first time demonstrate that Puerarin robustly attenuates NOX isoform-dependent ROS production and inflammatory activation in ACS exposed mice and CSE treated HSAECs, indicating that Puerarin might be used as a robust therapeutic agent for early or early stage COPD.

Traditional Herbal Medicine Discovery for the Treatment and Prevention of Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is characterized by pulmonary artery remodeling that may subsequently culminate in right heart failure and premature death. Although there are currently both non-pharmacological (lung transplantation, etc.) and pharmacological (Sildenafil, Bosentan, and new oral drugs on trial) therapies available, PAH remains a serious and fatal pulmonary disease. As a unique medical treatment, traditional herbal medicine (THM) treatment has gradually exerted its advantages in treating PAH worldwide through a multi-level and multi-target approach. Additionally, the potential mechanisms of THM were deciphered, including suppression of proliferation and apoptosis of pulmonary artery smooth muscle cells, controlling the processes of inflammation and oxidative stress, and regulating vasoconstriction and ion channels. In this review, the effects and mechanisms of the frequently studied compound THM, single herbal preparations, and multiple active components from THM are comprehensively summarized, as well as their related mechanisms on several classical preclinical PAH models. It is worth mentioning that sodium tanshinone IIA sulfonate sodium and tetramethylpyrazine are under clinical trials and are considered the most promoting medicines for PAH treatment. Last, reverse pharmacology, a strategy to discover THM or THM-derived components, has also been proposed here for PAH. This review discusses the current state of THM, their working mechanisms against PAH, and prospects of reverse pharmacology, which are expected to facilitate the natural anti-PAH medicine discovery and development and its bench-to-bedside transformation.

Punicalagin Protects Against Diabetic Cardiomyopathy by Promoting Opa1-Mediated Mitochondrial Fusion via Regulating PTP1B-Stat3 Pathway

Aims: This study aims to explore the efficacy of punicalagin (PG) on diabetic cardiomyopathy (DCM), with a specific focus on the mechanisms underlying the effects of PG on mitochondrial fusion/fission dynamics. Results: Cardiac structural and functional abnormalities were ameliorated in diabetic rats receiving PG administration as evidenced by increased ejection fraction, and attenuated myocardial fibrosis and hypertrophy. PG enhanced mitochondrial function and inhibited mitochondria-derived oxidative stress by promoting Opa1-mediated mitochondrial fusion. The benefits of PG could be abrogated by knockdown of Opa1 in vivo and in vitro. Inhibitor screening and chromatin immunoprecipitation analysis showed that Stat3 directly regulated the transcriptional expression of Opa1 by binding to its promoter and was responsible for PG-induced Opa1-mediated mitochondrial fusion. Moreover, pharmmapper screening and molecular docking studies revealed that PG embedded into the activity pocket of PTP1B and inhibited the activity of PTP1B. Overexpression of PTP1B blocked the promoting effect of PG on Stat3 phosphorylation and Opa1-mediated mitochondrial fusion, whereas knockdown of PTP1B mimicked the benefits of PG in high-glucose-treated cardiomyocytes. Innovation: Our study is the first to identify PG as a novel mitochondrial fusion promoter against hyperglycemia-induced mitochondrial oxidative injury and cardiomyopathy by upregulating Opa1 via regulating PTP1B-Stat3 pathway. Conclusion: PG protects against DCM by promoting Opa1-mediated mitochondrial fusion, a process in which PG interacts with PTP1B and inhibits its activity, which in turn increases Stat3 phosphorylation and then enhances the transcriptional expression of Opa1. These results suggest that PG might be a promising new therapeutic approach against diabetic cardiac complication. Antioxid. Redox Signal. 35, 618-641.

The effects and mechanisms of pomegranate in the prevention and treatment of metabolic syndrome

Metabolic syndrome, such as obesity, diabetes and cardiovascular disease, is becoming epidemic both in developing and developed countries in recent years. Vegetable and fruit consumptions have been associated with the prevention of metabolic syndrome. Pomegranate is a widely consumed fruit in Middle East and Asia. Currently, accumulating data showed that pomegranate exhibits antioxidant, anti-inflammatory, hypolipidemic and hypoglycemic activities in experimental and clinical studies. The beneficial effects of pomegranate may come from its rich polyphenols and be mediated by increasing the activity of AMPK, upregulating GLUT4, activating PPAR[Formula: see text]- ABCA1/CYP7A1 pathways and improving mitochondrial function. This review provides a systematical presentation of findings on the beneficial effects as well as the possible mechanisms of pomegranate and its major components on prevention and treatment of metabolic syndrome.

Pomegranate peel as a phytogenic in broiler chickens: Influence upon antioxidant, lipogenesis and hypotensive response

The aim of this study was to evaluate antioxidant, antihyperlipidemic and hypotensive properties of pomegranate peel (PP) on antioxidant status, fat deposition, lipid peroxidation and pulmonary hypertensive response in broiler chickens. A total of 375 one‐day‐old male broilers (Cobb 500) were randomly assigned to five treatments included dietary PP levels of 0, 2.5, 5.0, 7.5 and 10 g/kg. Supplementation of PP at 7.5 and 10 g/kg resulted in significant upregulation of hepatic catalase (p < 0.004) and superoxide dismutase1 (SOD1; p < 0.05), which reflected in decreased concentration of circulatory malondialdehyde (MDA). Dietary inclusion of PP at 7.5 and 1.0 g/kg significantly decreased serum concentrations of triglycerides (p < 0.004) and cholesterol (p < 0.006) with concomitant decrease in abdominal fat deposition (p < 0.05). The antihyperlipidemic effect of PP was mediated through down‐regulation of peroxisome proliferator activated receptor alpha (PPARα). Hypotensive effect of PP was also observed at 7.5 and 10 g/kg as reduced heart weight and the right‐to‐total ventricular weight ratio (RV/TV) and decreased mortality from pulmonary hypertension. The hypotensive property of PP was associated with increased concentration of serum nitric oxide. In conclusion, this study revealed antioxidative, antihyperlipidemic and hypotensive effects of PP at 7.5 and 10 g/kg in broiler chickens exposed to hypobaric hypoxia. Health‐beneficial effects of PP suggest this product as a promising multi‐functional phytogenic feed additive for broiler chickens.

In this study, evaluate antioxidant, antihyperlipidemic, and hypotensive properties of pomegranate peel (PP) on antioxidant status, fat deposition, lipid peroxidation, and pulmonary hypertensive response in broiler chickens. Supplementation of PP at 7.5 and 10 g/kg resulted in significant up‐regulation of hepatic catalase, superoxide dismutase1 and peroxisome proliferator activated receptor alpha (PPARα), which reflected in decreased concentration of circulatory malondialdehyde (MDA).

Therapeutic potential of plant-derived tannins in non-malignant respiratory diseases

Respiratory diseases are the major cause of human illness and death around the world. Despite advances in detection and treatment, very few classes of safe and effective therapy have been introduced to date. At present, phytochemicals are getting more attention because of their diverse beneficial activities and minimal toxicity. Tannins are polyphenolic secondary metabolites with high molecular weights, which are naturally present in a wide variety of fruits, vegetables, cereals, and leguminous seeds. Many tannins are endowed with well-recognized protective properties, such as anti-cancer, anti-microbial, anti-oxidant, anti-hyperglycemic, and many others. This review summarizes a large body of experimental evidence implicating that tannins are helpful in tackling a wide range of non-malignant respiratory diseases including acute lung injury (ALI), pulmonary fibrosis, asthma, pulmonary hypertension, and chronic obstructive pulmonary disease (COPD). Mechanistic pathways by which various classes of tannins execute their beneficial effects are discussed. In addition, clinical trials and our perspective on future research with tannins are also reviewed.

Stim-activated TRPC-ORAI channels in pulmonary hypertension induced by chronic intermittent hypoxia

Obstructive sleep apnea (OSA), a breathing disorder featured by chronic intermittent hypoxia (CIH) is associated with pulmonary hypertension (PH). Rodents exposed to CIH develop pulmonary vascular remodeling and PH, but the pathogenic mechanisms are not well known. Overexpression of Stim-activated Transient Receptor Potential Channels (TRPC) and Calcium Release-Activated Calcium Channel Protein (ORAI) TRPC-ORAI Ca²⁺ channels (STOC) has been involved in pulmonary vascular remodeling and PH in sustained hypoxia. However, it is not known if CIH may change STOC levels. Accordingly, we studied the effects of CIH on the expression of STOC subunits in the lung and if these changes paralleled the progression of the vascular pulmonary remodeling and PH in a preclinical model of OSA. Male Sprague-Dawley rats (∼200 g) were exposed to CIH (5%O₂, 12 times/h for 8 h) for 14, 21, and 28 days. We measured right ventricular systolic pressure (RVSP), cardiac morphometry with MRI, pulmonary vascular remodeling, and wire-myographic arterial responses to KCl and endothelin-1 (ET-1). Pulmonary RNA and protein STOC levels of TRPC1, TRPC4, TRPC6, ORAI 1, ORAI 2, and STIM1 subunits were measured by qPCR and western blot, and results were compared with age-matched controls. CIH elicited a progressive increase of RVSP and vascular contractile responses to KCl and ET-1, leading to vascular remodeling and augmented right ventricular ejection fraction, which was significant at 28 days of CIH. The levels of TRPC1, TRPC4, TRPC 6, ORAI 1, and STIM 1 channels increased following CIH, and some of them paralleled morphologic and functional changes. Our findings show that CIH increased pulmonary STOC expression, paralleling vascular remodeling and PH.

The risk of cardiovascular and cerebrovascular disease in overlap syndrome: a meta-analysis

STUDY OBJECTIVES

To undertake a meta-analysis of literature comparing the prevalence of cardiovascular and cerebrovascular comorbidities between patients with overlap syndrome (OS) and patients with chronic obstructive pulmonary disease (COPD) or patients with obstructive sleep apnea.

METHODS

Studies about the cardiovascular and cerebrovascular disease of OS were searched for among several electronic databases from the time of database construction to June 2019. Two independent reviewers performed the process of study screening, quality assessment, and data extraction. Meta-analysis of odds ratios (ORs) was carried out by RevMan5.3 under either fixed-effects or random-effects models. Sensitivity analysis was conducted to examine the robustness of pooled outcome.

RESULTS

A total of 17 articles were included. Compared with COPD/obstructive sleep apnea, OS significantly increased the risk of developing hypertension (OS vs COPD: OR = 1.94, 95% confidence interval [CI] [1.49, 2.52]; OS vs obstructive sleep apnea: OR = 2.05, 95% CI [1.57, 2.68]) and pulmonary hypertension (OS vs COPD: OR = 2.96, 95% CI [1.30, 6.77]; OS vs obstructive sleep apnea: OR = 5.93, 95% CI [1.84, 18.42]). There was no significant difference in the prevalence of coronary heart disease (OR = 1.19, 95% CI [.67,2.11]) and cerebrovascular disease (OR = 2.43, 95% CI [0.81, 7.31]) between patients with COPD and patients with OS. However, the sensitivity analysis showed that the pooled outcome of the comparison of pulmonary arterial pressure between patients with OS and patients with COPD was not stable.

CONCLUSIONS

OS significantly increased cardiovascular risk including the prevalence of hypertension and pulmonary hypertension. However, since the pooled outcome about pulmonary arterial pressure was not stable, further studies are still required.

Medicinal Plants and Phytochemicals for the Treatment of Pulmonary Hypertension

Background

Pulmonary hypertension (PH) is a progressive disease that is associated with pulmonary arteries remodeling, right ventricle hypertrophy, right ventricular failure and finally death. The present study aims to review the medicinal plants and phytochemicals used for PH treatment in the period of 1994 – 2019.

Methods

PubMed, Cochrane and Scopus were searched based on pulmonary hypertension, plant and phytochemical keywords from August 23, 2019. All articles that matched the study based on title and abstract were collected, non-English, repetitive and review studies were excluded.

Results

Finally 41 studies remained from a total of 1290. The results show that many chemical treatments considered to this disease are ineffective in the long period because they have a controlling role, not a therapeutic one. On the other hand, plants and phytochemicals could be more effective due to their action on many mechanisms that cause the progression of PH.

Conclusion

Studies have shown that herbs and phytochemicals used to treat PH do their effects from six mechanisms. These mechanisms include antiproliferative, antioxidant, antivascular remodeling, anti-inflammatory, vasodilatory and apoptosis inducing actions. According to the present study, many of these medicinal plants and phytochemicals can have effects that are more therapeutic than chemical drugs if used appropriately.

Antihypertensive phytocomplexes of proven efficacy and well-established use: Mode of action and individual characterization of the active constituents

Hypertension has become the leading risk factor for worldwide cardiovascular diseases. Conventional pharmacological treatment, after both dietary and lifestyle changes, is generally proposed. In this review, we present the antihypertensive properties of phytocomplexes from thirteen plants, long ago widely employed in ethnomedicines and, in recent years, increasingly evaluated for their activity in vitro and in vivo, also in humans, in comparison with synthetic drugs acting on the same systems. Here, we focus on the demonstrated or proposed mechanisms of action of such phytocomplexes and of their constituents proven to exert cardiovascular effects. Almost seventy phytochemicals are described and scientifically sound pertinent literature, published up to now, is summarized. The review emphasizes the therapeutic potential of these natural substances in the treatment of the 'high normal blood pressure' or 'stage 1 hypertension', so-named according to the most recent European and U.S. guidelines, and as a supplementation in more advanced stages of hypertension, however needing further validation by clinical trial intensification.

Flavonoid bioactive compounds of hawthorn extract can promote growth, regulate electrocardiogram waves, and improve cardiac parameters of pulmonary hypertensive chickens

The effect of orally administered hawthorn flavonoid extract (HFE) on growth, electrocardiographic waves, and cardiac parameters of pulmonary hypertensive chickens reared at high altitude (2,100 m above sea level) was examined. A total of 225 one-day-old, mixed broiler chicks (3 treatments with 5 replicates and 15 chicks per each, totally 75 birds/treatment) were assigned to 3 experimental groups: 0, 0.1, and 0.2 ml of HFE per 1 L of drinking water. Birds were administered the drinking water HFE treatments for 42 D. At an age of 28 and 42 D, electrocardiograms were undertaken and cardiac parameters such as the RV:TV, RV:BW, and TV:BW, and indicators of PHS on selected birds were measured. The final BW of chickens receiving the HFE at 0.2 ml/L was greater (2,579 ± 64 g) than that of birds receiving 0.1 ml/L (2,497 ± 62 g) and 0 ml/L (2,323 ± 57 g). Therefore, no supplemented group had a lower final BW than others (P < 0.05). Amplitudes of S and T waves in 0.1- and 0.2-ml/L HFE consumed groups at 28 and 42 D of age decreased compared with that in the control group (P < 0.05). The HFE reduced the heart weight and RV:TV, RV:BW, and TV:BW ratios when supplemented in drinking water at 0.1 and 0.2 mL/L compared with 0 mL/L (P < 0.05). In conclusion, supplementation of HFE in drinking water can reduce the PHS and incidence of cardiac disorders. Owing to the positive effect of HFE on cardiac parameters that mediated through flavonoids bioactive compounds, this product can be used to prevent complications of pulmonary hypertension and disarray of electrocardiographic waves in broiler chickens reared at high altitude.

Potential Contribution of Carotid Body-Induced Sympathetic and Renin-Angiotensin System Overflow to Pulmonary Hypertension in Intermittent Hypoxia

PURPOSE OF REVIEW

Obstructive sleep apnea (OSA), featured by chronic intermittent hypoxia (CIH), is an independent risk for systemic hypertension (HTN) and is associated with pulmonary hypertension (PH). The precise mechanisms underlying pulmonary vascular remodeling and PH in OSA are not fully understood. However, it has been suggested that lung tissue hypoxia, oxidative stress, and pro-inflammatory mediators following CIH exposure may contribute to PH.

RECENT FINDINGS

New evidences obtained in preclinical OSA models support that an enhanced carotid body (CB) chemosensory reactiveness to oxygen elicits sympathetic and renin-angiotensin system (RAS) overflow, which contributes to HTN. Moreover, the ablation of the CBs abolished the sympathetic hyperactivity and HTN in rodents exposed to CIH. Accordingly, it is plausible that the enhanced CB chemosensory reactivity may contribute to the pulmonary vascular remodeling and PH through the overactivation of the sympathetic-RAS axis. This hypothesis is supported by the facts that (i) CB stimulation increases pulmonary arterial pressure, (ii) denervation of sympathetic fibers in pulmonary arteries reduces pulmonary remodeling and pulmonary arterial hypertension (PAH) in humans, and (iii) administration of angiotensin-converting enzyme (ACE) or blockers of Ang II type 1 receptor (ATR1) ameliorates pulmonary remodeling and PH in animal models. In this review, we will discuss the supporting evidence for a plausible contribution of the CB-induced sympathetic-RAS axis overflow on pulmonary vascular remodeling and PH induced by CIH, the main characteristic of OSA.

Aloperine suppresses human pulmonary vascular smooth muscle cell proliferation via inhibiting inflammatory response

Abnormal pulmonary arterial vascular smooth muscle cells (PASMCs) proliferation is critical pathological feature of pulmonary vascular remodeling that acts as driving force in the initiation and development of pulmonary arterial hypertension (PAH), ultimately leading to pulmonary hypertension. Aloperine is a main active alkaloid extracted from the traditional Chinese herbal Sophora alopecuroides and possesses outstanding antioxidation and anti-inflammatory effects. Our group found Aloperine has protective effects on monocroline-induced pulmonary hypertension in rats by inhibiting oxidative stress in previous researches. However, the anti-inflammation effects of Aloperine on PAH remain unclear. Therefore, to further explore whether the beneficial role of Aloperine on PAH was connected with its anti-inflammatory effects, we performed experiments in vitro. Aloperine significantly inhibited the proliferation and DNA synthesis of human pulmonary artery smooth muscle cells (HPASMCs) induced by platelet-derived growth factor-BB, blocked progression through G₀/G₁to S phase of the cell cycle and promoted total ratio of apoptosis. In summary, these results suggested that Aloperine negatively regulated nuclear factor-κB signaling pathway activity to exert protective effects on PAH and suppressed HPASMCs proliferation therefore has a potential value in the treatment of pulmonary hypertension by negatively modulating pulmonary vascular remodeling.

Protection of the myocardium against ischemia/reperfusion injury by punicalagin through an SIRT1-NRF-2-HO-1-dependent mechanism

Punicalagin has been found to exert cardiac protective effects against myocardial ischemia/reperfusion (MI/R) injury, although the detailed mechanisms remain largely unknown. This experiment was performed to explore the potential involvement of silent information regulator 1 (SIRT1)-NFE2-related factor 2 (NRF-2)-heme oxygenase-1 (HO-1) pathway in the cardiac protective actions of punicalagin. Sprague-Dawley (SD) rats were subjected to MI/R operation with or without punicalagin treatment (40 mg kg^-1d^-1). We showed that punicalagin-treated group exhibited enhanced cardiac function, reduced myocardial infarction and decreased cleaved caspase-3 level. Furthermore, myocardial oxidative/nitrosative stress was ameliorated by punicalagin as evidenced by suppressed superoxide generation, gp91^phox and iNOS expressions, NO metabolites as well as myocardial nitrotyrosine level. Additionally, punicalagin decreased myocardial IL-6, TNF-α and the levels of ICAM-1, VCAM-1 and IKK-β expressions as well as IκB-α phosphorylation and NF-κB nuclear translocation. However, these effects were abolished by EX527 (5 mg kg^-1d^-1, a selective SIRT1 inhibitor). We further found that punicalagin dose-dependently enhanced SIRT1 nuclear distribution and NRF-2-HO-1 signaling. While EX527 treatment not only reduced SIRT1 activity, but also reversed the activation of NRF-2-HO-1 pathway. Collectively, these results revealed that punicalagin reduced cardiac oxidative/nitrosative stress and inflammatory response induced by MI/R operation through SIRT1-mediated activation of NRF-2-HO-1 signaling.

Ethnomedicine, Phytochemistry and Pharmacology of Smilax glabra: An Important Traditional Chinese Medicine

Smilax glabra (SG) Roxb., a well-known traditional Chinese medicine, has been extensively used worldwide for its marked pharmacological activities for treating syphilitic poisoned sores, limb hypertonicity, morbid leucorrhea, eczema pruritus, strangury due to heat, carbuncle toxin, and many other human ailments. Approximately 200 chemical compounds have been isolated from SG Roxb., and the major components have been determined to be flavonoids and flavonoid glycosides, phenolic acids, and steroids. Among these active compounds, the effects of astilbin, which is used as a quality control marker to determine the quality of SG Roxb., have been widely investigated. Based on in vivo and in vitro studies, the primary active components of SG Roxb. possess various pharmacological activities, such as cytotoxic, anti-inflammatory and immune-modulatory effects, anti-oxidant, hepatoprotective, antiviral, antibacterial, and cardiovascular system protective activities. However, an extensive study to determine the relationship between the chemical compositions and pharmacological effects of SG Roxb. has not been conducted and is worth of our study. Improving the means of utilizing the effects of SG is crucial. The present paper reviews the ethnopharmacology, phytochemistry, and pharmacology of SG Roxb. and assesses its ethnopharmacological use in order to explore its therapeutic potential for future research.

Effects of FHL1 and P21 on hypoxia-induced pulmonary vascular remodeling in neonatal rats

Numerous studies have demonstrated that altered expression levels of four and a half LIM domains 1 (FHL1) and P21 are necessary for hypoxia-induced pulmonary vascular remodeling in both adult rats and human patients with idiopathic pulmonary arterial hypertension. However, whether FHL1 and P21 are present in the pulmonary artery and whether these proteins affect pulmonary vascular remodeling in hypoxia-induced pulmonary hypertension (HPH) in neonatal rats remain unknown. The present study investigated the effects of altered FHL1 and P21 expression on pulmonary vascular remodeling in neonatal rats with HPH. A total of 32 newborn Sprague-Dawley rats were exposed to hypoxia or room air for 7 or 14 days (n=8/subgroup). Parameters including the percentage of medial wall thickness (WT%), the percentage of medial wall area (WA%), right ventricular (RV) mean pressure, RV hypertrophy index (RVHI) and RV systolic pressure (RVSP) were measured to evaluate the development of HPH. Additionally, the expressions of FHL1 and P21 in the pulmonary artery smooth muscle cells (PASMCs) were measured by reverse transcription-quantitative polymerase chain reaction, western blot analysis and immunohistochemical staining. WA%, WT%, RV mean pressure, RVHI and RVSP were significantly increased in the HPH model group when compared with the control group (P<0.01). The protein expression levels of FHL1 were significantly increased in the HPH group (P<0.05), while the mRNA and protein expression levels of P21 were significantly reduced (P<0.05). Pearson correlation analysis indicated that the protein expressions of FHL1 and P21 were correlated with WA% and WT% (all P<0.001), and that the protein expression of P21 was negatively correlated with that of FHL1 (P<0.01). The results indicated that the expressions of FHL1 and P21 were altered in the PASMCs of newborn rats with HPH. Furthermore, FHL1 and P21 may serve important roles in pulmonary vascular remodeling.

Astragalus Polysaccharides Attenuate Monocrotaline-Induced Pulmonary Arterial Hypertension in Rats

Astragalus polysaccharides (APS) have been shown to possess a variety of biological activities including anti-oxidant and anti-inflammation functions in a number of diseases. However, their function in pulmonary arterial hypertension (PAH) is still unknown. Rats received APS (200[Formula: see text]mg/kg once two days) for 2 weeks after being injected with monocrotaline (MCT; 60[Formula: see text]mg/kg). The pulmonary hemodynamic index, right ventricular hypertrophy, and lung morphological features of the rat models were examined, as well as the NO/eNOS ratio of wet lung and dry lung weight and MPO. A qRT-PCR and p-I[Formula: see text]B was used to assess IL-1[Formula: see text], IL-6 and TNF-[Formula: see text] and WB was used to detect the total I[Formula: see text]B. Based on these measurements, it was found that APS reversed the MCT-induced increase in mean pulmonary arterial pressure (mPAP) (from 32.731[Formula: see text]mmHg to 26.707[Formula: see text]mmHg), decreased pulmonary vascular resistance (PVR) (from 289.021[Formula: see text]mmHg[Formula: see text][Formula: see text] min/L to 246.351[Formula: see text]mmHg[Formula: see text][Formula: see text][Formula: see text]min/L), and reduced right ventricular hypertrophy (from 289.021[Formula: see text]mmHg[Formula: see text][Formula: see text][Formula: see text]min/L to 246.351 mmHg[Formula: see text][Formula: see text][Formula: see text]min/L) ([Formula: see text]0.05). In terms of pulmonary artery remodeling, the WT% and WA% decreased with the addition of APS. In addition, it was found that APS promoted the synthesis of eNOS and the secretion of NO, promoting vasodilation and APS decreased the MCT-induced elevation of MPO, IL-1[Formula: see text], IL-6 and TNF-[Formula: see text], reducing inflammation. Furthermore, APS was able to inhibit the activation of pho-I[Formula: see text]B[Formula: see text]. In couclusion, APS ameliorates MCT-induced pulmonary artery hypertension by inhibiting pulmonary arterial remodeling partially via eNOS/NO and NF-[Formula: see text]B signaling pathways.

Punicalagin reduces H2O2-induced cytotoxicity and apoptosis in PC12 cells by modulating the levels of reactive oxygen species

BACKGROUND

Oxidative stress has long been linked to neuronal cell death in many neurodegenerative diseases. Antioxidant conventional supplements are poorly effective in preventing neuronal damage caused by oxidative stress due to their inability to cross the blood brain barrier. Hence the use of molecules extracted from plants and fruits such as phenolics, flavonoids, and terpenoids compounds constitute a new wave of antioxidant therapies to defend against free radicals.

OBJECTIVE

In this study we examined the effects of punicalagin, a ellagitannin isolated from the pomegranate juice, on a rat adrenal pheochromocytoma cell line, treated with hydrogen peroxide, evaluating the viability, oxidation potential, mitochondrial function, and eventual apoptosis.

METHODS

This study was performed on PC12 cells pretreated with punicalagin (0.5, 1, 5, 10 e 20 µM) 24 hours before of the damage by hydrogen peroxide (H₂O₂). H₂O₂ concentration (300 µM) used in our study was determined by preliminary experiments of time course. The cell viability and ROS production were evaluated by MTS assay and cytofluorometry assays, respectively. Subsequently, the number of apoptotic-positive cells and mitochondrial transmembrane potential, were measured by flow cytometry, in the same experimental paradigm. Finally, the expression of Bax and enzymatic activity of Caspase 3, some of the principle actors of programmed cell death, were investigated by semiquantitative PCR and utilizing a colorimetric assay kit, respectively.

RESULTS

We found that pretreatment with punicalagin protected the cells from H₂O₂-induced damage. In particular, the protective effect seemed to be correlated with a control both in radical oxygen species production and in mitochondrial functions. In fact the cells treated with H₂O₂ showed an altered mitochondrial membrane integrity while the pretreatment with punicalagin retained both the cellular viability and the mitochondrial membrane potential similar to the control. Furthermore, the punicalagin, modulated the apoptotic cascade triggered reducing Bax gene expression and Caspase 3 activity.

DISCUSSION

Results of the present study demonstrated a neuroprotective effect of punicalagin on H₂O₂-induced PC12 cell death, including mitochondria damage and expression of apoptotic gene Bax; therefore we hypothesize a possible prevent role for this molecule in neurodegenerative diseases related to oxidative stress.