Rhodiola crenulata Extract Alleviates Hypoxic Pulmonary Edema in Rats

Elucidating the role of Rhodiola rosea L. in sepsis-induced acute lung injury via network pharmacology: emphasis on inflammatory response, oxidative stress, and the PI3K-AKT pathway

CONTEXT

Sepsis-induced acute lung injury (ALI) is associated with high morbidity and mortality. Rhodiola rosea L. (Crassulaceae) (RR) and its extracts have shown anti-inflammatory, antioxidant, immunomodulatory, and lung-protective effects.

OBJECTIVE

This study elucidates the molecular mechanisms of RR against sepsis-induced ALI.

MATERIALS AND METHODS

The pivotal targets of RR against sepsis-induced ALI and underlying mechanisms were revealed by network pharmacology and molecular docking. Human umbilical vein endothelial cells (HUVECs) were stimulated by 1 μg/mL lipopolysaccharide for 0.5 h and treated with 6.3, 12.5, 25, 50, 100, and 200 μg/mL RR for 24 h. Then, the lipopolysaccharide-stimulated HUVECs were subjected to cell counting kit-8 (CCK-8), enzyme-linked immunosorbent, apoptosis, and Western blot analyses. C57BL/6 mice were divided into sham, model, low-dose (40 mg/kg), mid-dose (80 mg/kg), and high-dose (160 mg/kg) RR groups. The mouse model was constructed through caecal ligation and puncture, and histological, apoptosis, and Western blot analyses were performed for further validation.

RESULTS

We identified six hub targets (MPO, HRAS, PPARG, FGF2, JUN, and IL6), and the PI3K-AKT pathway was the core pathway. CCK-8 assays showed that RR promoted the viability of the lipopolysaccharide-stimulated HUVECs [median effective dose (ED50) = 18.98 μg/mL]. Furthermore, RR inhibited inflammation, oxidative stress, cell apoptosis, and PI3K-AKT activation in lipopolysaccharide-stimulated HUVECs and ALI mice, which was consistent with the network pharmacology results.

DISCUSSION AND CONCLUSION

This study provides foundational knowledge of the effective components, potential targets, and molecular mechanisms of RR against ALI, which could be critical for developing targeted therapeutic strategies for sepsis-induced ALI.

Investigating the multitarget pharmacological mechanism of Rhodiola wallichiana var. cholaensis acting on angina pectoris using combined network pharmacology and molecular docking

Background

Rhodiola wallichiana var. cholaensis (RW) is one of the traditional Chinese medicinal materials, which is used to treat angina pectoris (AP). However, the possible underlying mechanisms remains unclear. The aim of this study was to explore RW in the treatment of AP and to identify the potential mechanism of the core compounds.

Methods

In this study, systematic and comprehensive network pharmacology and molecular docking were used for the first time to explore the potential pharmacological mechanisms of RW on AP. First, the relative compounds were obtained by mining the literature, and potential targets of these compounds using target prediction were collected. We then built the AP target database using the DigSee and GeneCards databases. Based on the data, overlapping targets and hub genes were identified with Maximal Clique Centrality (MCC) algorithm in Cytoscape, cytoHubba. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses and protein-protein interaction (PPI) analysis were performed to screen the hub targets by topology. Molecular docking was utilized to investigate the receptor-ligand interactions on Autodock Vina and visualized in PyMOL.

Results

A total of 218 known RW therapeutic targets were selected. Systematic analysis identified nine hub targets (VEGFA, GAPDH, TP53, AKT1, CASP3, STAT3, TNF, MAPK1 and JUN) mainly involved in the complex treatment effects associated with the protection of the vascular endothelium, as well as the regulation of glucose metabolism, cellular processes, inflammatory responses, and cellular signal transduction. Molecular docking indicated that the core compounds had good affinity with the core targets.

Conclusions

The results of this study preliminarily identify the potential targets and signaling pathways of RW in AP therapy and lay a promising foundation for further experimental studies and clinical trials.

Unraveling the protective mechanisms of Chuanfangyihao against acute lung injury: Insights from experimental validation

Chuanfangyihao (CFYH) is an effective treatment for acute lung injury (ALI) in clinical practice; however, its underlying mechanism of action remains unclear. Therefore, the aim of the present study was to elucidate the pharmacological mechanism of action of CFYH in ALI through experimental validation. First, a rat model of ALI was established using lipopolysaccharide (LPS). Next, the pathological changes in the lungs of the rats and the pathological damage were scored. The wet/dry weight ratios were measured, and ROS content was detected using flow cytometry. ELISA was used to examine IL-6, TNF-α, IL-1β, IL-18, and LDH levels. Immunohistochemistry was used to detect Beclin-1 and NLRP3 expression. Western blotting was performed to analyze the expression of HMGB1, RAGE, TLR4, NF-κB p65, AMPK, p-AMPK, mTOR, p-mTOR, Beclin-1, LC3-II/I, p62, Bcl-2, Bax, Caspase-3, Caspase-1, and GSDMD-NT. The mRNA levels of HMGB1, RAGE, AMPK, mTOR, and HIF-1α were determined using reverse transcription quantitative PCR. CFYH alleviated pulmonary edema and decreased the expression of IL-6, TNF-α, TLR4, NF-κB p65, HMGB1/RAGE, ROS, and HIF-1α. In addition, pretreatment with CFYH reversed ALI-induced programmed cell death. In conclusion, CFYH alleviates LPS-induced ALI, and these findings provide a preliminary clarification of the predominant mechanism of action of CFYH in ALI.

Promising Natural Medicines for the Treatment of High-Altitude Illness

Li Li, Lin Lin, Bo Wen, Peng-cheng Zhao, Da-sheng Liu, Guo-ming Pang, Zi-rong Wang, Yong Tan, and Cheng Lu. Promising natural medicines for the treatment of high-altitude illness. High Alt Med Biol. 24:175-185, 2023.-High-altitude illness (HAI) is a dangerous disease characterized by oxidative stress, inflammatory damage and hemodynamic changes in the body that can lead to severe damage to the lungs, heart, and brain. Natural medicines are widely known for their multiple active ingredients and pharmacological effects, which may be important in the treatment of HAI. In this review, we outline the specific types of HAI and the underlying pathological mechanisms and summarize the currently documented natural medicines applied in the treatment of acute mountain sickness and high-altitude cerebral edema, high-altitude pulmonary edema, chronic mountain sickness, and high-altitude pulmonary hypertension. Their sources, types, and medicinal sites are summarized, and their active ingredients, pharmacological effects, related mechanisms, and potential toxicity are discussed. In conclusion, natural medicines, as an acceptable complementary and alternative strategy with fewer side effects and more long-term application, can provide a reference for developing more natural antialtitude sickness medicines in the future and have good application prospects in HAI treatment.

Traditional Chinese medicine in the era of immune checkpoint inhibitor: theory, development, and future directions

Immune checkpoint inhibitors (ICIs) have revolutionized cancer management and have been widely applied; however, they still have some limitations in terms of efficacy and toxicity. There are multiple treatment regimens in Traditional Chinese Medicine (TCM) that play active roles in combination with Western medicine in the field of oncology treatment. TCM with ICIs works by regulating the tumor microenvironment and modulating gut microbiota. Through multiple targets and multiple means, TCM enhances the efficacy of ICIs, reverses resistance, and effectively prevents and treats ICI-related adverse events based on basic and clinical studies. However, there have been few conclusions on this topic. This review summarizes the development of TCM in cancer treatment, the mechanisms underlying the combination of TCM and ICIs, existing studies, ongoing trials, and prospects for future development.

Tibetan medicine salidroside improves host anti-mycobacterial response by boosting inflammatory cytokine production in zebrafish

The treatment for tuberculosis (TB), especially multidrug-resistant TB (MDR-TB), has a prolonged cycle which can last up to a year. This is partially due to the lack of effective therapies. The development of novel anti-TB drugs from the perspective of host immune regulation can provide an important supplement for conventional treatment strategies. Salidroside (SAL), a bioactive component from the Tibetan medicine Rhodiola rosea, has been used in the treatment of TB, although its mechanism remains unclear. Here, the bacteriostatic effect of SAL in vivo was first demonstrated using a zebrafish–M. marinum infection model. To further investigate the underlying mechanism, we then examined the impact of SAL on immune cell recruitment during wound and infection. Increased macrophage and neutrophil infiltrations were found both in the vicinity of the wound and infection sites after SAL treatment compared with control, which might be due to the elevated chemokine expression levels after SAL treatment. SAL treatment alone was also demonstrated to improve the survival of infected zebrafish larvae, an effect that was amplified when combining SAL treatment with isoniazid or rifampicin. Interestingly, the reduced bacterial burden and improved survival rate under SAL treatment were compromised in tnfα-deficient embryos which suggests a requirement of Tnfα signaling on the anti-mycobacterial effects of SAL. In summary, this study provides not only the cellular and molecular mechanisms for the host anti-mycobacterial effects of the Tibetan medicine SAL but also proof of concept that combined application of SAL with traditional first-line anti-TB drugs could be a novel strategy to improve treatment efficacy.

Oxidative Stress and Diseases Associated with High-Altitude Exposure

Several diseases associated with high-altitude exposure affect unacclimated individuals. These diseases include acute mountain sickness (AMS), high-altitude cerebral edema (HACE), high-altitude pulmonary edema (HAPE), chronic mountain sickness (CMS), and, notably, high-altitude pulmonary hypertension (HAPH), which can eventually lead to right ventricle hypertrophy and heart failure. The development of these pathologies involves different molecules and molecular pathways that might be related to oxidative stress. Studies have shown that acute, intermittent, and chronic exposure to hypobaric hypoxia induce oxidative stress, causing alterations to molecular pathways and cellular components (lipids, proteins, and DNA). Therefore, the aim of this review is to discuss the oxidative molecules and pathways involved in the development of high-altitude diseases. In summary, all high-altitude pathologies are related to oxidative stress, as indicated by increases in the malondialdehyde (MDA) biomarker and decreases in superoxide dismutase (SOD) and glutathione peroxidase (GPx) antioxidant activity. In addition, in CMS, the levels of 8-iso-PGF2α and H₂O₂ are increased, and evidence strongly indicates an increase in Nox4 activity in HAPH. Therefore, antioxidant treatments seem to be a promising approach to mitigating high-altitude pathologies.

[Betelnut polyphenols provide protection against high-altitude hypoxia in rats]

OBJECTIVE

To investigate the protective effects of betelnut polyphenols on the vital organs against high-altitude hypoxia in rats.

OBJECTIVE

We compared low-, medium-, and high- dose betelnut polyphenols (400, 800, and 1600 mg/kg, respectively) and rhodiola the effects of against high-altitude hypoxia in Wistar rats. The rats were kept in normal condition and given the drugs daily for 3 days before transfer to a facility at the altitude of 4010 m, where the rats were kept for 5 consecutive days for hypoxic exposure. The rats were then euthanized for measuring arterial blood gas and assessing liver, lung, brain and cardiac pathologies with HE staining. SOD activity, MDA content and GSH content in the organs were measured, and serum levels of inflammatory factors were detected using a protein microarray.

OBJECTIVE

Acute exposure to hypoxia significantly reduced blood oxygen saturation of the rats (P < 0.05), caused damages in the liver, lung, brain and myocardium, lowered SOD activity and GSH content and increased MDA content in the vital organs, and increased serum levels of TIMP-1, MCP-1, ICAM-1, and L-selectin (P < 0.05). Treatment with betelnut polyphenols significantly improved blood oxygen saturation, alleviated organ damages, decreased MDA content and increased SOD activity and GSH content in the tissues, and significantly lowered serum levels of inflammatory cytokines in rats with acute exposure to high-altitude hypoxia (P < 0.05).

OBJECTIVE

Betelnut polyphenols provides protection of the vital organs against acute high-altitude hypoxia in rats by enhancing the antioxidant capacity and reducing inflammatory response.

Chinese medicinal plants for the potential management of high-altitude pulmonary oedema and pulmonary hypertension

CONTEXT

Despite the abundance of knowledge regarding high-altitude pulmonary edoema (HAPE) and high-altitude pulmonary hypertension (HAPH), their prevalence continues to be on the rise. Thus, there is an urgent need for newer safe, effective, and relatively economic drug candidates. China is particularly known for the use of medicinal plants.

OBJECTIVE

This review summarizes the medicinal plants used for HAPE and HAPH in the past 30 years, as well as some potential plants.

METHODS

Publications on HAPE and HAPH from 1990 to 2020 were identified using Web of Science, PubMed, SCOPUS, Springer Link, Google Scholar databases, Chinese Clinical Trial Registry and CNKI with the following keywords: 'medicinal plants,' 'hypoxia,' 'high altitude pulmonary edema,' 'high altitude pulmonary hypertension,' 'pathophysiology,' 'mechanisms,' 'prevention,' 'treatment,' 'human,' 'clinical,' 'safety,' and 'pharmacokinetics.'

RESULTS

We found 26 species (from 20 families) out of 5000 plants which are used for HAPE and HAPH prevention or treatment. Rhodiola rosea Linn. (Crassulaceae) is the most widely utilized. The most involved family is Lamiaceae, which contains 5 species.

DISCUSSION AND CONCLUSIONS

We mainly reviewed the medicinal plants and mechanisms for the treatment of HAPE and HAPH, and we also assessed related toxicology experiments, pharmacokinetics and bioavailability. Potential medicinal plants were also identified. Further research is needed to determine the pharmacological effects and active ingredients of these potential medicinal plants.

Dammarane-Type Saponins from Gynostemma pentaphyllum Prevent Hypoxia-Induced Neural Injury through Activation of ERK, Akt, and CREB Pathways

Gynostemma pentaphyllum possesses neuroprotective bioactivity. However, the effect of gypenosides on hypoxia-induced neural damage remains obscure. In this study, Gyp, the active fraction extracted from G. pentaphyllum and its bioactive compounds as well as the underlying molecular mechanisms were investigated. Eighteen dammarane-type saponins were isolated from Gyp. The absolute configurations of six unreported compounds (13-18) were assessed via electron capture detection (ECD) analyses. The results of cell viability assay showed that Gyp and its bioactive compounds (13-16 and 18) effectively protected PC12 cells from hypoxia injury. Gyp pretreatment also improved mice spatial memory impairment caused by hypoxia exposure. At the molecular level, Gyp and its bioactive compounds could activate the signaling pathways of ERK, Akt, and CREB in vitro and in vivo. In summary, Gyp and its bioactive compounds could prevent hypoxia-induced injury via ERK, Akt, and CREB signaling pathways.

Alterations of Human Plasma Proteome Profile on Adaptation to High-Altitude Hypobaric Hypoxia

For individuals migrating to or residing permanently in high-altitude regions, environmental hypobaric hypoxia is a primary challenge that induces several physiological or pathological responses. It is well documented that human beings adapt to hypobaric hypoxia via some protective mechanisms, such as erythropoiesis and overproduction of hemoglobin; however, little is known on the alterations of plasma proteome profiles in accommodation to high-altitude hypobaric hypoxia. In the present study, we investigated differential plasma proteomes of high altitude natives and lowland normal controls by a TMT-based proteomic approach. A total of 818 proteins were identified, of which 137 were differentially altered. Bioinformatics (including GO, KEGG, protein-protein interactions, etc.) analysis showed that the differentially altered proteins were basically involved in complement and coagulation cascades, antioxidative stress, and glycolysis. Validation results demonstrated that CCL18, C9, PF4, MPO, and S100A9 were notably up-regulated, and HRG and F11 were down-regulated in high altitude natives, which were consistent with TMT-based proteomic results. Our findings highlight the contributions of complement and coagulation cascades, antioxidative stress, and glycolysis in acclimatization to hypobaric hypoxia and provide a foundation for developing potential diagnostic or/and therapeutic biomarkers for high altitude hypobaric hypoxia-induced diseases.

Protective Effects of Rhodiola Crenulata Extract on Hypoxia-Induced Endothelial Damage via Regulation of AMPK and ERK Pathways

Rhodiola crenulata root extract (RCE) has been shown to possess protective activities against hypoxia both in vitro and in vivo. However, the effects of RCE on response to hypoxia in the endothelium remain unclear. In this study, we aimed to examine the effects of RCE in endothelial cells challenged with hypoxic exposure and to elucidate the underlying mechanisms. Human umbilical vein endothelial cells were pretreated with or without RCE and then exposed to hypoxia (1% O₂) for 24 h. Cell viability, nitric oxide (NO) production, oxidative stress markers, as well as mechanistic readouts were studied. We found that hypoxia-induced cell death, impaired NO production, and oxidative stress. These responses were significantly attenuated by RCE treatment and were associated with the activation of AMP-activated kinase and extracellular signal-regulated kinase 1/2 signaling pathways. In summary, we showed that RCE protected endothelial cells from hypoxic insult and suggested that R. crenulata might be useful for the prevention of hypoxia-associated vascular dysfunction.

The impact of Rhodiola rosea on the gut microbial community of Drosophila melanogaster

Background

The root extract of Rhodiola rosea has historically been used in Europe and Asia as an adaptogen, and similar to ginseng and Shisandra, shown to display numerous health benefits in humans, such as decreasing fatigue and anxiety while improving mood, memory, and stamina. A similar extract in the Rhodiola family, Rhodiola crenulata, has previously been shown to confer positive effects on the gut homeostasis of the fruit fly, Drosophila melanogaster. Although, R. rosea has been shown to extend lifespan of many organisms such as fruit flies, worms and yeast, its anti-aging mechanism remains uncertain. Using D. melanogaster as our model system, the purpose of this work was to examine whether the anti-aging properties of R. rosea are due to its impact on the microbial composition of the fly gut.

Results

Rhodiola rosea treatment significantly increased the abundance of Acetobacter, while subsequently decreasing the abundance of Lactobacillales of the fly gut at 10 and 40 days of age. Additionally, supplementation of the extract decreased the total culturable bacterial load of the fly gut, while increasing the overall quantifiable bacterial load. The extract did not display any antimicrobial activity when disk diffusion tests were performed on bacteria belonging to Microbacterium, Bacillus, and Lactococcus.

Conclusions

Under standard and conventional rearing conditions, supplementation of R. rosea significantly alters the microbial community of the fly gut, but without any general antibacterial activity. Further studies should investigate whether R. rosea impacts the gut immunity across multiple animal models and ages.

The Influence of CO2 and Exercise on Hypobaric Hypoxia Induced Pulmonary Edema in Rats

Introduction: Individuals with a known susceptibility to high altitude pulmonary edema (HAPE) demonstrate a reduced ventilation response and increased pulmonary vasoconstriction when exposed to hypoxia. It is unknown whether reduced sensitivity to hypercapnia is correlated with increased incidence and/or severity of HAPE, and while acute exercise at altitude is known to exacerbate symptoms the effect of exercise training on HAPE susceptibility is unclear.

Purpose: To determine if chronic intermittent hypercapnia and exercise increases the incidence of HAPE in rats.

Methods: Male Wistar rats were randomized to sedentary (sed-air), CO₂ (sed-CO₂,) exercise (ex-air), or exercise + CO₂ (ex-CO₂) groups. CO₂ (3.5%) and treadmill exercise (15 m/min, 10% grade) were conducted on a metabolic treadmill, 1 h/day for 4 weeks. Vascular reactivity to CO₂ was assessed after the training period by rheoencephalography (REG). Following the training period, animals were exposed to hypobaric hypoxia (HH) equivalent to 25,000 ft for 24 h. Pulmonary injury was assessed by wet/dry weight ratio, lung vascular permeability, bronchoalveolar lavage (BAL), and histology.

Results: HH increased lung wet/dry ratio (HH 5.51 ± 0.29 vs. sham 4.80 ± 0.11, P < 0.05), lung permeability (556 ± 84 u/L vs. 192 ± 29 u/L, P < 0.001), and BAL protein (221 ± 33 μg/ml vs. 114 ± 13 μg/ml, P < 0.001), white blood cell (1.16 ± 0.26 vs. 0.66 ± 0.06, P < 0.05), and platelet (16.4 ± 2.3, vs. 6.0 ± 0.5, P < 0.001) counts in comparison to normobaric normoxia. Vascular reactivity was suppressed by exercise (−53% vs. sham, P < 0.05) and exercise+CO₂ (−71% vs. sham, P < 0.05). However, neither exercise nor intermittent hypercapnia altered HH-induced changes in lung wet/dry weight, BAL protein and cellular infiltration, or pulmonary histology.

Conclusion: Exercise training attenuates vascular reactivity to CO₂ in rats but neither exercise training nor chronic intermittent hypercapnia affect HH- induced pulmonary edema.

Astragaloside II promotes intestinal epithelial repair by enhancing L-arginine uptake and activating the mTOR pathway

Astragaloside II (AS II) extracted from Astragalus membranaceus has been reported to promote tissue wound repair. However, the effect of AS II on inflammatory bowel disease is unknown. We investigated the effects and mechanism of AS II on intestinal wound healing in both in vitro and in vivo models. Human intestinal Caco-2 cells were treated with multiple concentrations of AS II to assess cell proliferation, scratch wound closure, L-arginine uptake, cationic amino acid transporter activity, and activation of the mTOR signaling pathway. These effects were also measured in a mouse model of colitis. AS II promoted wound closure and increased cell proliferation, L-arginine uptake, CAT1 and CAT2 protein levels, total protein synthesis, and phosphorylation of mTOR, S6K, and 4E-BP1 in Caco-2 cells. These effects were suppressed by lysine or rapamycin treatment, suggesting that the enhanced arginine uptake mediates AS II-induced wound healing. Similar results were also observed in vivo. Our findings indicate that AS II can contribute to epithelial barrier repair following intestinal injury, and may offer a therapeutic avenue in treating irritable bowel disease.

In Vitro Anticancer Activity and Structural Characterization of Ubiquinones from Antrodia cinnamomea Mycelium

Two new ubiquinones, named antrocinnamone and 4-acetylantrocamol LT3, were isolated along with six known ubiquinones from Antrodia cinnamomea (Polyporaceae) mycelium. The developed HPLC analysis methods successfully identified eight different ubiquinones, two benzenoids, and one maleic acid derivative from A. cinnamomea. The ubiquinones 1-8 exhibited potential and selective cytotoxic activity against three human cancer cell lines, with IC50 values ranging from 0.001 to 35.883 μM. We suggest that the different cytotoxicity levels were related to their chemical structures, especially the 4-hydroxycyclohex-2-enone ring and the presence of a free hydroxyl group in the side chain. The suppression by 4-acetylantrocamol LT3 stopped the cell cycle at the beginning of the G2-M phase thus making the cell cycle arrest at the sub-G1 phase as compared with control cells.

Protective Effects of Cucurbitacin B on Acute Lung Injury Induced by Sepsis in Rats

Background

The aim of this study was to investigate the protective effects of cucurbitacin B (CuB) on sepsis-induced acute lung injury (ALI) in rats.

Material/Methods

An ALI model was made by cecal ligation and puncture (CLP) in SD rats. Rats were randomly divided into 5 groups (n=15 per group): animals undergoing a sham CLP (sham group); animals undergoing CLP (CLP control group); animals undergoing CLP and treated with CuB at 1 mg/kg of body weight (bw) (low-dose CuB [L-CuB] group), animals undergoing CuB at 2 mg/kg of bw (mid-dose CuB [M-CuB] group); and animals undergoing CuB at 5 mg/kg of bw (high-dose CuB [H-CuB] group). Samples of blood and lung tissue were harvested at different time points (6, 12, and 24 hour post-CLP surgery) for the detection of indicators which represented ALI. Five rats were respectively sacrificed at each time point. Pathological changes of lung tissue were observed by H&E staining. Another 50 rats were distributed into the same five groups to record the 72 hour survival rates.

Results

Treatment with CuB significantly increased the blood gas PaO2 levels and decreased lung wet/dry (W/D) ratio (p<0.05). It significantly reduced protein concentration, accumulation of the inflammatory cells, and levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), (p<0.05), in the bronchoalveolar lavage fluid (BALF). Pulmonary pathological damage and survival rates at 72 hours were found to be effectively improved by CuB. In addition, CuB performed its pulmonary protection effects in a dose-depended manner.

Conclusions

CuB can effectively improve the pulmonary gas exchange function, reduce pulmonary edema, and inhibit the inflammatory response in the lung, revealing that CuB may serve as a potential therapeutic strategy for sepsis-induced ALI.

Protective Effects of Tyrosol against LPS-Induced Acute Lung Injury via Inhibiting NF-κB and AP-1 Activation and Activating the HO-1/Nrf2 Pathways

Tyrosol (Tyr) is a natural antioxidant that displays anti-oxidant and anti-inflammatory properties. The present study aimed to investigate the effect and mechanism of Tyr on lipopolysaccharide (LPS)-induced acute lung injury (ALI). In a mouse model, we found that pretreatment with Tyr significantly improved survival rate, attenuated lung permeability, ameliorated histopathological alterations, reduced expression of the inflammatory mediators and improved expression of the antioxidant enzyme. Further study revealed that Tyr markedly inhibited nuclear factor-κB (NF-κB) and activator protein-1 (AP-1) activation at both in vivo and in vitro levels. To investigate the underlying mechanism, we examined the impact of Tyr on the heme oxygenase (HO)-1/nuclear factor erythroid-2 related factor 2 (Nrf2) pathway in vivo and in vitro. The results showed that Tyr significantly improved the expression of HO-1 and the activation of Nrf2. This study offers novel evidence to support the efficacy of Tyr against ALI, which helps to clarify the underlying causes of the therapeutic effects behind Tyr.

Rhodiola crenulata extract counteracts the effect of hypobaric hypoxia in rat heart via redirection of the nitric oxide and arginase 1 pathway

BACKGROUND

Rhodiola crenulata is traditionally used as a folk medicine in Tibet for preventing high-altitude illnesses, including sudden cardiac death (SCD). The cardio-protective effects of Rhodiola crenulata root extract (RCE) against hypoxia in vivo have been recently confirmed. However, the way in which RCE produces these effects remains unclear. The present study is designed to confirm the protective effects of RCE on the heart in acute hypobaric hypoxia exposure and examine the mechanisms by which this occurs.

METHODS

Sprague-Dawley (SD) rats were pretreated with or without RCE and then exposed to a simulated altitude of 8000 m in a hypobaric hypoxia chamber for 9 h. The expression of cardiac arginase 1 (Arg-1) and endothelial nitric oxide synthase (eNOS) and the activity of associated signaling pathways was examined.

RESULTS

Hypoxia reduced cardiac eNOS phosphorylation and increased Arg-1 expression, but both responses were reversed by RCE pre-treatment. In addition, RCE decreased the hypoxia-induced oxidative stress markers of reactive oxygen species (ROS) production, malondialdehyde (MDA) level, and protein carbonyl content. Furthermore, RCE protected cardiomyocytes from hypoxia-induced cardiac apoptosis and restored the phosphorylation level of AKT and p38 MAPK as well as the superoxide dismutase 2 (SOD2) content in hypoxic animals.

CONCLUSION

The findings provide evidence that the effects of Rhodiola crenulata against altitude illness are partially mediated by modulation of eNOS and Arg-1 pathways in the heart.

Comparative Study on the Protective Effects of Salidroside and Hypoxic Preconditioning for Attenuating Anoxia-Induced Apoptosis in Pheochromocytoma (PC12) Cells

BACKGROUND Hypoxia is an important sign that can result from body injuries or a special condition such as being at a high altitude or deep water diving. In the current studies, hypoxic preconditioning (HPC) plays a key role in reducing hypoxia-induced apoptosis. We aimed to study the pharmacologic preconditioning effects of salidroside versus those of HPC in hypoxia-/anoxia-induced apoptosis in PC12 cells (pheochromocytoma). MATERIAL AND METHODS PC12 cells were treated by different experimental conditions: control condition, hypoxia condition, HPC condition, low-/middle-/high-dose condition of salidroside, cyclosporine A (CsA), and oratractyloside (ATR). The cell viability, lactate dehydrogenase (LDH) activity, apoptosis, mitochondrial membrane potential (MMP), intracellular Ca2+, caspase-3 activity, and expression of Bcl-2 were detected in PC12 cells after the hypoxia treatment. Salidroside, extracted from the traditional Chinese herb Rhodiola rosea L, plays an essential role in reducing hypoxia-induced apoptosis in PC12 cells by the mitochondrial pathway. RESULTS Salidroside decreased the apoptosis and increased the viability of hypoxia-induced PC12 cells more effectively than HPC Moreover, salidroside markedly stabilized MMP and intracellular Ca2+, reduced or inhibited LDH and caspase-3 activity, and up-regulated Bcl-2; CsA and ATR showed corresponding function. CONCLUSIONS Salidroside administration restrains apoptosis induced by hypoxia in PC12 cells. The protective effects are mediated by preservation of mitochondrial integrity and MMP to inhibit the excessive Ca2+ influx and caspase-3 activity and to promote the Bcl-2 expression, providing a potential clinical and effective therapeutic mechanism to reduce deaths from ischemic or hypoxic injury.

Nanocurcumin accords protection against acute hypobaric hypoxia induced lung injury in rats

Decline in oxygen availability experienced under hypobaric hypoxia (HH) mediates imbalance in lung fluid clearance and is a causative agent of acute lung injury. Here, we investigate the pathological events behind acute HH mediated lung injury and assess the therapeutic efficacy of nanocurcumin in its amelioration. We assess the protective efficacy of nanotized curcumin (nanocurcumin) in ameliorating HH induced lung injury and compare to curcumin. Rats exposed to acute HH (6, 12, 24, 48 and 72 h) were subjected to histopathology, blood-gas analysis and clinical biochemistry, cytokine response and redox damage. HH induced lung injury was analysed using markers of lung injury due to pulmonary vasoconstriction (ET-1/2/3 and endothelin receptors A and B) and trans-vascular fluid balance mediator (Na+/K+ ATPase). The protective efficacy of nanocurcumin was analysed by examination of Akt/Erk signalling cascade by western blot. HH induced lung injury was associated with discrete changes in blood analytes, differential circulatory cytokine response and severe pulmonary redox damages. Up-regulation of ET-1/2/3 and its receptors along with down-regulation of Na+/K+ ATPase confirmed defective pulmonary fluid clearance which promoted edema formation. Nanocurcumin treatment prevented lung edema formation and restored expression levels of ET-1/2/3 and its receptors while restoring the blood analytes, circulatory cytokines and pulmonary redox status better than curcumin. Modulation in Akt/Erk signalling pathway in rat lungs under HH confirmed the protective efficacy of nanocurcumin.

Rhodiola crenulata extract regulates hepatic glycogen and lipid metabolism via activation of the AMPK pathway

Background

Metabolic syndrome may lead to many complications, such as nonalcoholic fatty liver disease (NAFLD). A natural and effective therapeutic agent for patients with NAFLD is urgently needed. In a previous study, we showed that Rhodiola crenulata root extract (RCE) regulated hepatic gluconeogenesis through activation of AMPK signaling. However, the manner in which RCE regulates hepatic lipid and glycogen metabolism remains unclear. The current study was conducted to investigate the effects of RCE on hepatic glycogen and lipid metabolism, as well as the mechanisms underlying such effects.

Methods

Human hepatoma HepG2 cells were treated with RCE for 6 h under high glucose conditions, after which glycogen synthesis, lipogenesis, and relative gene expression were examined. In addition, lipogenesis-related genes were investigated in vivo.

Results

RCE significantly increased glycogen synthesis and inhibited lipogenesis, while regulating genes related to these processes, including glycogen synthase kinase 3β (GSK3β), glycogen synthase (GS), fatty acid synthase (FAS), CCAAT/enhancer-binding protein (C/EBP), and sterol regulatory element-binding protein 1c (SREBP-1c). However, the effects caused by RCE were neutralized by compound C, an AMPK antagonist. Further studies showed that expression levels of lipogenic genes decreased at the protein and mRNA levels in the rat liver.

Conclusions

Our results demonstrate that RCE regulates hepatic glycogen and lipid metabolism through the AMPK signaling pathway. These results suggest that RCE is a potential intervention for patients with NAFLD.

Effects of rhodiola crenulata on mice hearts under severe sleep apnea

BACKGROUND

The goal of this study is to determine if Rhodiola Crenulata (RC) has protective effects on mice hearts with severe sleep apnea model.

METHODS

Sixty-four C57BL/6 J mice 5-6 months old were distributed into 4 groups i.e. Control group (21% O2, 24 h per day, 8 weeks, n=16); Hypoxia group (Hypoxia: 7% O2 60 s, 20% O2 alternating 60 s, 8 h per day, 8 weeks, n=16); Hypoxia+90RC and Hypoxia+270RC group (Hypoxia for 1st 4 weeks and hypoxia pretreated 90 mg/Kg and 270 mg/Kg Rhodiola Crenulata by oral gavage per day for 2nd 4 weeks, each n=16). Excised hearts from 4 groups of mice were analyzed for heart weight index changes using H&E staining, TUNEL-positive assays and Western Blotting protein.

RESULTS

Cardiac widely dispersed TUNEL-positive apoptotic cells in mice hearts were less in Hypoxia+RC90 and Hypoxia+RC270 than those in Hypoxia. Compared with Hypoxia, the protein levels of Fas ligand, Fas death receptors, Fas-Associated Death Domain (FADD), activated caspase 8, and activated caspase 3 (Fas dependent apoptotic pathways) were decreased in Hypoxia+RC90, Hypoxia+RC270. The protein levels of Bad, Bax, t-Bid, activated caspase 9, activated caspase 3 (mitochondria dependent apoptotic pathway) were less in Hypoxia+RC90, Hypoxia+RC270 than those in hypoxia. The protein levels of Bcl2, Bcl-xL, p-Bad (Bcl2-realted anti-apoptotic pathway) and VEGF, p-PI3k, p-AKT (VEGF-related pro-survival pathway) were higher in Hypoxia+RC90, Hypoxia+RC270 than those in hypoxia.

CONCLUSIONS

Our findings suggest that Rhodiola Crenulata have protective effects on chronic intermittent hypoxia-induced cardiac widely dispersed apoptosis via Fas-dependent and mitochondria-dependent apoptotic and VEGF-related pro-survival pathway.

Rhodiola crenulata extract suppresses hepatic gluconeogenesis via activation of the AMPK pathway

BACKGROUND

Rhodiola, a popular herb, has been used for treating high altitude sicknesses, depression, fatigue, and diabetes. However, the detailed mechanisms by which Rhodiola crenulata functions in the liver need further clarification.

PURPOSE

The current study was designed to examine the effects of Rhodiola crenulata root extract (RCE) on hepatic glucose production.

METHODS

Human hepatoma HepG2 cells were treated with RCE for 6 h. Glucose production, the expression level of p-AMPK, and the expression of key gluconeogenic genes were measured. The effects of RCE were also studied in Sprague-Dawley (SD) rats. The efficacy and underlying mechanism of RCE in the liver were examined.

RESULTS

RCE significantly suppressed glucose production and gluconeogenic gene expression in HepG2 cells while activating the AMPK signaling pathway. Interestingly, RCE-suppressed hepatic gluconeogenesis was eliminated by an AMPK-specific inhibitor, but not by the PI3K/AKT-specific inhibitor. In addition, oral administration of RCE significantly increased phosphorylated AMPK levels and inhibited gluconeogenic gene expression in the rat liver. Furthermore, RCE treatment also decreased plasma glucose concentration in rats.

CONCLUSION

We present in vitro and in vivo evidence that RCE might exert the glucose-lowering effect partly by inhibiting hepatic gluconeogenesis through activating the AMPK signaling pathway. These findings provide evidence that Rhodiola crenulata may be helpful for the management of type II diabetes.

Salidroside alleviates paraquat-induced rat acute lung injury by repressing TGF-β1 expression

OBJECTIVE

This study was designed to investigate the protective effects of salidroside (SDS) via suppressing the expression of transforming growth factor-β1 (TGF-β1) in rat acute lung injury (ALI) induced by paraquat (PQ) and to explore the potential molecular mechanisms.

METHODS

A total of 90 male rats (190-210 g) were randomly and evenly divided into 9 groups: control group, PQ groups (4 groups), and PQ + SDS groups (4 groups). The rats in control group were treated with equal volume of saline intraperitoneally. The rats in PQ groups were exposed to PQ solution (20 mg/kg) by gastric gavage for 1, 6, 24, and 72 hours, respectively. The rats in PQ + SDS groups were intraperitoneally injected once with SDS (10 mg/kg) every 12 hours after PQ perfusion. Pulmonary pathological changes were observed by hematoxylin and eosin (HE) staining. The expression of TGF-β1 and the mRNA were evaluated by immunohistochemical (IHC) scoring and real time quantitative reverse transcription polymerase chain reaction (real-time qRT-PCR), respectively.

RESULTS

SDS alleviated the symptoms of PQ induced ALI. Moreover, SDS reduced the expression of the inflammatory cytokine TGF-β1 including TGF-β1 IHC scores (at each time point from 6 to 72 hours after PQ perfusion) and mRNA level (at each time point from 1 to 72 hours after PQ perfusion) compared with PQ groups (P < 0.05).

CONCLUSION

SDS alleviated the pulmonary symptoms of PQ-induced ALI, at least partially, by repressing inflammatory cell infiltration and the expression of TGF-β1 resulting in delayed lung fibrosis.

Rhodiola crenulata extract for prevention of acute mountain sickness: a randomized, double-blind, placebo-controlled, crossover trial

BACKGROUND

Rhodiola crenulata (R. crenulata) is widely used to prevent acute mountain sickness in the Himalayan areas and in Tibet, but no scientific studies have previously examined its effectiveness. We conducted a randomized, double-blind, placebo-controlled crossover study to investigate its efficacy in acute mountain sickness prevention.

METHODS

Healthy adult volunteers were randomized to 2 treatment sequences, receiving either 800 mg R. crenulata extract or placebo daily for 7 days before ascent and 2 days during mountaineering, before crossing over to the alternate treatment after a 3-month wash-out period. Participants ascended rapidly from 250 m to 3421 m on two separate occasions: December 2010 and April 2011. The primary outcome measure was the incidence of acute mountain sickness, as defined by a Lake Louise score ≥ 3, with headache and at least one of the symptoms of nausea or vomiting, fatigue, dizziness, or difficulty sleeping.

RESULTS

One hundred and two participants completed the trial. There were no demographic differences between individuals taking Rhodiola-placebo and those taking placebo-Rhodiola. No significant differences in the incidence of acute mountain sickness were found between R. crenulata extract and placebo groups (all 60.8%; adjusted odds ratio (AOR) = 1.02, 95% confidence interval (CI) = 0.69-1.52). The incidence of severe acute mountain sickness in Rhodiola extract vs. placebo groups was 35.3% vs. 29.4% (AOR = 1.42, 95% CI = 0.90-2.25).

CONCLUSIONS

R. crenulata extract was not effective in reducing the incidence or severity of acute mountain sickness as compared to placebo.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01536288.

Rhodiola crenulata and Its Bioactive Components, Salidroside and Tyrosol, Reverse the Hypoxia-Induced Reduction of Plasma-Membrane-Associated Na,K-ATPase Expression via Inhibition of ROS-AMPK-PKC ξ Pathway

Exposure to hypoxia leads to impaired pulmonary sodium transport, which is associated with Na,K-ATPase dysfunction in the alveolar epithelium. The present study is designed to examine the effect and mechanism of Rhodiola crenulata extract (RCE) and its bioactive components on hypoxia-mediated Na,K-ATPase endocytosis. A549 cells were exposed to hypoxia in the presence or absence of RCE, salidroside, or tyrosol. The generation of intracellular ROS was measured by using the fluorescent probe DCFH-DA, and the endocytosis was determined by measuring the expression level of Na,K-ATPase in the PM fraction. Rats exposed to a hypobaric hypoxia chamber were used to investigate the efficacy and underlying mechanism of RCE in vivo. Our results showed that RCE and its bioactive compounds significantly prevented the hypoxia-mediated endocytosis of Na,K-ATPase via the inhibition of the ROS-AMPK-PKCζ pathway in A549 cells. Furthermore, RCE also showed a comparable preventive effect on the reduction of Na,K-ATPase endocytosis and inhibition of AMPK-PKCξ pathway in the rodent model. Our study is the first to offer substantial evidence to support the efficacy of Rhodiola products against hypoxia-associated Na,K-ATPase endocytosis and clarify the ethnopharmacological relevance of Rhodiola crenulata as a popular folk medicine for high-altitude illness.