Salvianolic acid B attenuates lipopolysaccharide-induced acute lung injury in rats through inhibition of apoptosis, oxidative stress and inflammation

Protective effects of salvianolic acid B on intestinal ischemia/reperfusion injury in rats by regulating the AhR/IL-22/STAT6 axis

PURPOSE

Intestinal ischemia/reperfusion (I/R) injury (IIRI) is associated with high morbidity and mortality. Salvianolic acid B (Sal-B) could exert neuroprotective effects on reperfusion injury after cerebral vascular occlusion, but its effect on IIRI remains unclear. This study set out to investigate the protective effects of Sal-B on IIRI in rats.

METHODS

The rat IIRI model was established by occluding the superior mesenteric artery and reperfusion, and they were pretreated with Sal-B and aryl hydrocarbon receptor (AhR) antagonist CH-223191 before surgery. Pathological changes in rat ileum, IIRI degree, and intestinal cell apoptosis were evaluated through hematoxylin-eosin staining, Chiu's score scale, and TUNEL staining, together with the determination of caspase-3, AhR protein level in the nucleus, and STAT6 phosphorylation by Western blotting. The levels of inflammatory cytokines (IL-1β/IL-6/TNF-α) and IL-22 were determined by ELISA and RT-qPCR. The contents of superoxide dismutase (SOD), glutathione (GSH), and malondialdehyde (MDA) in intestinal tissues were determined by spectrophotometry.

RESULTS

Sal-B alleviated IIRI in rats, evidenced by slight villi shedding and villi edema, reduced Chiu's score, and diminished the number of TUNEL-positive cells and caspase-3 expression. SAL-B alleviated inflammation and oxidative stress (OS) responses induced by IIRI. Sal-B promoted IL-22 secretion by activating AhR in intestinal tissue after IIRI. Inhibition of AhR activation partially reversed the protective effect of Sal-B on IIRI. Sal-B promoted STAT6 phosphorylation by activating the AhR/IL-22 axis.

CONCLUSION

Sal-B plays a protective role against IIRI in rats by activating the AhR/IL-22/STAT6 axis, which may be achieved by reducing the intestinal inflammatory response and OS responses.

Jinyinqingre Oral Liquid alleviates LPS-induced acute lung injury by inhibiting the NF-κB/NLRP3/GSDMD pathway

Acute lung injury (ALI) is a prevalent and severe clinical condition characterized by inflammatory damage to the lung endothelial and epithelial barriers, resulting in high incidence and mortality rates. Currently, there is a lack of safe and effective drugs for the treatment of ALI. In a previous clinical study, we observed that Jinyinqingre oral liquid (JYQR), a Traditional Chinese Medicine formulation prepared by the Taihe Hospital, Affiliated Hospital of Hubei University of Medicine, exhibited notable efficacy in treating inflammation-related hepatitis and cholecystitis in clinical settings. However, the potential role of JYQR in ALI/acute respiratory distress syndrome (ARDS) and its anti-inflammatory mechanism remains unexplored. Thus, the present study aimed to investigate the therapeutic effects and underlying molecular mechanisms of JYQR in ALI using a mouse model of lipopolysaccharide (LPS)-induced ALI and an in vitro RAW264.7 cell model. JYQR yielded substantial improvements in LPS-induced histological alterations in lung tissues. Additionally, JYQR administration led to a noteworthy reduction in total protein levels within the BALF, a decrease in MPAP, and attenuation of pleural thickness. These findings collectively highlight the remarkable efficacy of JYQR in mitigating the deleterious effects of LPS-induced ALI. Mechanistic investigations revealed that JYQR pretreatment significantly inhibited NF-κB activation and downregulated the expressions of the downstream proteins, namely NLRP3 and GSDMD, as well as proinflammatory cytokine levels in mice and RAW2647 cells. Consequently, JYQR alleviated LPS-induced ALI by inhibiting the NF-κB/NLRP3/GSDMD pathway. JYQR exerts a protective effect against LPS-induced ALI in mice, and its mechanism of action involves the downregulation of the NF-κB/NLRP3/GSDMD inflammatory pathway.

Salvianolic Acid A Protects against Lipopolysaccharide-Induced Acute Lung Injury by Inhibiting Neutrophil NETosis

Salvianolic acid A (SAA) is one of bioactive polyphenol extracted from a Salvia miltiorrhiza (Danshen), which was widely used to treat cardiovascular disease in traditional Chinese medicine. SAA has been reported to be protective in cardiovascular disease and ischemia injury, with anti-inflammatory and antioxidative effect, but its role in acute lung injury (ALI) is still unknown. In this study, we sought to investigate the therapeutic effects of SAA in a murine model of lipopolysaccharide- (LPS-) induced ALI. The optimal dose of SAA was determined by comparing the attenuation of lung injury score after administration of SAA at three different doses (low, 5 mg/kg; medium, 10 mg/kg; and, high 15 mg/kg). Dexamethasone (DEX) was used as a positive control for SAA. Here, we showed that the therapeutic effect of SAA (10 mg/kg) against LPS-induced pathologic injury in the lungs was comparable to DEX. SAA and DEX attenuated the increased W/D ratio and the protein level, counts of total cells and neutrophils, and cytokine levels in the BALF of ALI mice similarly. The oxidative stress was also relieved by SAA and DEX according to the superoxide dismutase and malondialdehyde. NET level in the lungs was elevated in the injured lung while SAA and DEX reduced it significantly. LPS induced phosphorylation of Src, Raf, MEK, and ERK in the lungs, which was inhibited by SAA and DEX. NET level and phosphorylation level of Src/Raf/MEK/ERK pathway in the neutrophils from acute respiratory distress syndrome (ARDS) patients were also inhibited by SAA and DEX in vitro, but the YEEI peptide reversed the protective effect of SAA completely. The inhibition of NET release by SAA was also reversed by YEEI peptide in LPS-challenged neutrophils from healthy volunteers. Our data demonstrated that SAA ameliorated ALI via attenuating inflammation, oxidative stress, and neutrophil NETosis. The mechanism of such protective effect might involve the inhibition of Src activation.

Salvianolic Acid B Alleviates Myocardial Ischemia Injury by Suppressing NLRP3 Inflammasome Activation via SIRT1-AMPK-PGC-1α Signaling Pathway

Salvianolic acid B (SalB) has been extensively investigated in our laboratory for myocardial ischemia (MI) disease. This study mainly aimed to illustrate the relationship between SIRT1 and the therapeutic effect of SalB on MI in rats and hypoxia damage in H9c2 cells. Furthermore, whether the antagonism of NLRP3 by SalB in the injuries mentioned above is related to SIRT1-AMPK-PGC-1α pathway-mediated mitochondrial biogenesis was further investigated. In vivo, 24 h after MI surgery, we found that SalB effectively reduced ST-segment elevation, myocardial infarct size enlargement, cardiac injury markers, myocardial structural abnormalities, and myocardial apoptotic cells in MI injury rats. In vitro, after 4 h of hypoxia exposure, SalB alleviated cell injury, inhibited the production of ROS and IL-1β, and prevented the loss of mitochondrial membrane potential (MMP). Besides, SalB downregulated the critical components of the NLRP3 inflammasome and upregulated the SIRT1-AMPK-PGC-1α signaling pathway-related molecules in myocardial tissues and H9c2 cells. However, all the above protective effects of SalB on MI could be offset by EX527. Taken together, our findings indicated that SalB could attenuate MI injury by targeting NLRP3, which is at least partially dependent on the SIRT1/AMPK/PGC-1α signaling pathway.

Promising Therapeutic Candidate for Myocardial Ischemia/Reperfusion Injury: What Are the Possible Mechanisms and Roles of Phytochemicals?

Percutaneous coronary intervention (PCI) is one of the most effective reperfusion strategies for acute myocardial infarction (AMI) despite myocardial ischemia/reperfusion (I/R) injury, causing one of the causes of most cardiomyocyte injuries and deaths. The pathological processes of myocardial I/R injury include apoptosis, autophagy, and irreversible cell death caused by calcium overload, oxidative stress, and inflammation. Eventually, myocardial I/R injury causes a spike of further cardiomyocyte injury that contributes to final infarct size (IS) and bound with hospitalization of heart failure as well as all-cause mortality within the following 12 months. Therefore, the addition of adjuvant intervention to improve myocardial salvage and cardiac function calls for further investigation. Phytochemicals are non-nutritive bioactive secondary compounds abundantly found in Chinese herbal medicine. Great effort has been put into phytochemicals because they are often in line with the expectations to improve myocardial I/R injury without compromising the clinical efficacy or to even produce synergy. We summarized the previous efforts, briefly outlined the mechanism of myocardial I/R injury, and focused on exploring the cardioprotective effects and potential mechanisms of all phytochemical types that have been investigated under myocardial I/R injury. Phytochemicals deserve to be utilized as promising therapeutic candidates for further development and research on combating myocardial I/R injury. Nevertheless, more studies are needed to provide a better understanding of the mechanism of myocardial I/R injury treatment using phytochemicals and possible side effects associated with this approach.

Salvianolic acid B blocks hepatic stellate cell activation via FGF19/FGFR4 signaling

INTRODUCTION AND OBJECTIVES

The activation of hepatic stellate cells (HSCs) is the main cause of liver fibrosis. The beneficial effects of fibroblast growth factor (FGF) 19 on liver fibrosis were recently reported. The S. miltiorrhiza as well as S. miltiorrhiza derived bioactive chemical components has shown prominent antifibrotic effects in liver fibrosis but the mechanism is still not fully understood. We aimed to investigate the bioactive compounds derived from S. miltiorrhiza which exerts antifibrotic effects in HSCs via regulating FGF19.

MATERIALS AND METHODS

FGF19 level in culture media was determined by enzyme-linked immunosorbent assay. Cell proliferation was measured by Cell Counting Kit-8 assay. Further, mRNA and protein expressions were assessed by quantitative polymerase chain reaction and western blotting, respectively. Knocking down of FGF receptor 4 (FGFR4) by transfection with siRNA was used to confirm the role of FGF19/FGFR4 signaling.

RESULTS

Using the human HSC cell line LX-2, we screened several natural products and found that bioactive compounds isolated from Salvia miltiorrhiza, particularly salvianolic acid B, strongly upregulated FGF19 secretion by LX-2 cells. We further showed that salvianolic acid B inhibited lipopolysaccharide (LPS)-induced HSC proliferation and activation. LPS treatment may also reduce the mRNA and protein levels of FGF19 and its receptor FGFR4. Salvianolic acid B treatment restored the impaired expressions of FGF19 and FGFR4. Finally, FGFR4 knockdown abolished the antifibrotic effects of salvianolic acid B in the LPS-induced HSC activation model.

CONCLUSIONS

Salvianolic acid B prevented LPS-induced HSC proliferation and activation by enhancing antifibrotic FGF19/FGFR4 signaling.

Effects of Traditional Chinese Medication-Based Bioactive Compounds on Cellular and Molecular Mechanisms of Oxidative Stress

The oxidative stress reaction is the imbalance between oxidation and antioxidation in the body, resulting in excessive production of oxygen free radicals in the body that cannot be removed, leading to excessive oxidation of the body, and causing damage to cells and tissues. A large number of studies have shown that oxidative stress is involved in the pathological process of many diseases, so inhibiting oxidative stress, that is, antioxidation, is of great significance for the treatment of diseases. Studies have shown that many traditional Chinese medications contain antioxidant active bioactive compounds, but the mechanisms of those compounds are different and complicated. Therefore, by summarizing the literature on antioxidant activity of traditional Chinese medication-based bioactive compounds in recent years, our review systematically elaborates the main antioxidant bioactive compounds contained in traditional Chinese medication and their mechanisms, so as to provide references for the subsequent research.

Regulation of PINX1 expression ameliorates lipopolysaccharide-induced lung injury and alleviates cell senescence during the convalescent phase through affecting the telomerase activity

PIN2/TERF1-interacting telomerase inhibitor 1 (PINX1) is necessary for telomerase reverse transcriptase (TERT) elements to bind at telomeres and non-telomere sites. We aimed to investigate the role of PINX1 and TERT in lipopolysaccharide (LPS)-induced lung injury during acute stage and convalescent phase. Lung injury rat model was induced, and the expression of PINX1 and TERT in serum and lung tissues was examined using RT-qPCR on day 0 (D0), D3, and D14, respectively. The pathologic changes of lung tissues on D3 and D14 were detected using hematoxylin and eosin staining after TERT overexpression, PINX1 overexpression, or PINX1 silencing in lung injury rats. Results revealed that TERT was persistently reduced on D3 and D14, while PINX1 was decreased on D3 but increased on D14. TERT overexpression and PINX1 silencing led to the most serious lung damage, the highest levels of inflammatory factors and apoptosis on D3, while the best recovery was observed on D14. Simultaneously, PINX1 overexpression presented the opposite effects at acute stage and convalescent phase. Co-immunoprecipitation (co-IP) assay verified the connection between PINX1 and TERT. Taken together, these findings demonstrated that regulation of PINX1 expression ameliorates lung injury and alleviates cell senescence during the convalescent phase through affecting the telomerase activity.

Chinese Herbs and Repurposing Old Drugs as Therapeutic Agents in the Regulation of Oxidative Stress and Inflammation in Pulmonary Diseases

Several pro-inflammatory factors and proteins have been characterized that are involved in the pathogenesis of inflammatory diseases, including acute respiratory distress syndrome, chronic obstructive pulmonary disease, and asthma, induced by oxidative stress, cytokines, bacterial toxins, and viruses. Reactive oxygen species (ROS) act as secondary messengers and are products of normal cellular metabolism. Under physiological conditions, ROS protect cells against oxidative stress through the maintenance of cellular redox homeostasis, which is important for proliferation, viability, cell activation, and organ function. However, overproduction of ROS is most frequently due to excessive stimulation of either the mitochondrial electron transport chain and xanthine oxidase or reduced nicotinamide adenine dinucleotide phosphate (NADPH) by pro-inflammatory cytokines, such as interleukin-1β and tumor necrosis factor α. NADPH oxidase activation and ROS overproduction could further induce numerous inflammatory target proteins that are potentially mediated via Nox/ROS-related transcription factors triggered by various intracellular signaling pathways. Thus, oxidative stress is considered important in pulmonary inflammatory processes. Previous studies have demonstrated that redox signals can induce pulmonary inflammatory diseases. Thus, therapeutic strategies directly targeting oxidative stress may be effective for pulmonary inflammatory diseases. Therefore, drugs with anti-inflammatory and anti-oxidative properties may be beneficial to these diseases. Recent studies have suggested that traditional Chinese medicines, statins, and peroxisome proliferation-activated receptor agonists could modulate inflammation-related signaling processes and may be beneficial for pulmonary inflammatory diseases. In particular, several herbal medicines have attracted attention for the management of pulmonary inflammatory diseases. Therefore, we reviewed the pharmacological effects of these drugs to dissect how they induce host defense mechanisms against oxidative injury to combat pulmonary inflammation. Moreover, the cytotoxicity of oxidative stress and apoptotic cell death can be protected via the induction of HO-1 by these drugs. The main objective of this review is to focus on Chinese herbs and old drugs to develop anti-inflammatory drugs able to induce HO-1 expression for the management of pulmonary inflammatory diseases.

Heme oxygenase-1(HO-1) regulates Golgi stress and attenuates endotoxin-induced acute lung injury through hypoxia inducible factor-1α (HIF-1α)/HO-1 signaling pathway

Sepsis caused acute lung injury (ALI) is a kind of serious disease in critically ill patients with very high morbidity and mortality. Recently, it has been demonstrated that Golgi is involved in the process of oxidative stress. However, whether Golgi stress is associated with oxidative stress in septic induced acute lung injury has not been elucidated. In this research, we found that lipopolysaccharide (LPS) induced oxidative stress, apoptosis, inflammation and Golgi morphology changes in acute lung injury both in vivo and in vitro. The knockout of heme oxygenase-1(HO-1) aggravated oxidative stress, inflammation, apoptosis and reduced the expression of Golgi matrix protein 130 (GM130), mannosidase Ⅱ, Golgi-associated protein golgin A1 (Golgin 97), and increased the expression of Golgi phosphoprotein 3 (GOLPH3), which caused the fragmentation of Golgi. Furtherly, the activation of hypoxia inducible factor-1α (HIF-1α)/HO-1 pathway, attenuates Golgi stress and oxidative stress by increasing the levels of GM130, mannosidase Ⅱ, Golgin 97, and decreasing the expression of GOLPH3 both in vivo and in vitro. Therefore, the activation of HO-1 plays a crucial role in alleviating sepsis-induced acute lung injury by regulating Golgi stress, oxidative stress, which may provide a therapeutic target for the treatment of acute lung injury.

Salvianolic Acid B Protects Intervertebral Discs from Oxidative Stress-Induced Degeneration via Activation of the JAK2/STAT3 Signaling Pathway

OBJECTIVE

To evaluate the influence of salvianolic acid B (SAB), an antioxidant derived from Danshen, on intervertebral disc degeneration (IDD) and its possible molecular mechanisms.

METHODS

Sixty adult rats were randomly grouped (control, IDD, and SAB IDD groups). IDD was induced using needle puncture. The rats received daily administration of SAB (20 mg/kg) in the SAB IDD group while the other two groups received only distilled water. The extent of IDD was evaluated using MRI after 3 and 6 weeks and histology after 6 weeks. Oxidative stress was assessed using the ELISA method. In in vitro experiments, nucleus pulposus cells (NPCs) were treated with H2O2 (100 μM) or SAB+H2O2, and levels of oxidative stress were measured. Cell apoptosis was assessed by flow cytometry, expression levels of Bcl-2, Bax, and cleaved caspase-3 proteins. Cell proliferation rate was assessed by EdU analysis. Pathway involvement was determined by Western blotting while the influence of the pathway on NPCs was explored using the pathway inhibitor AG490.

RESULTS

The data demonstrate that SAB attenuated injury-induced IDD and oxidative stress, caused by activation of the JAK2/STAT3 signaling pathway in vivo. Oxidative stress induced by H2O2 was reversed by SAB in vitro. SAB reduced the increased cell apoptosis, cleaved caspase-3 expression, and caspase-3 activity induced by H2O2. Reduced cell proliferation and decreased Bcl-2/Bax ratio induced by H2O2 were rescued by SAB. Additionally, the JAK2/STAT3 pathway was activated by SAB, while AG490 counteracted this effect.

CONCLUSION

The results suggest that SAB protects intervertebral discs from oxidative stress-induced degeneration by enhancing proliferation and attenuating apoptosis via activation of the JAK2/STAT3 signaling pathway.

Pharmacological Effects of Salvianolic Acid B Against Oxidative Damage

Salvianolic acid B (Sal B) is one of the main active ingredients of Salvia miltiorrhiza, with strong antioxidant effects. Recent findings have shown that Sal B has anti-inflammatory, anti-apoptotic, anti-fibrotic effects and can promote stem cell proliferation and differentiation, and has a beneficial effect on cardiovascular and cerebrovascular diseases, aging, and liver fibrosis. Reactive oxygen species (ROS) include oxygen free radicals and oxygen-containing non-free radicals. ROS can regulate cell proliferation, survival, death and differentiation to regulate inflammation, and immunity, while Sal B can scavenge oxygen free radicals by providing hydrogen atoms and reduce the production of oxygen free radicals and oxygen-containing non-radicals by regulating the expression of antioxidant enzymes. The many pharmacological effects of Sal B may be closely related to its elimination and inhibition of ROS generation, and Nuclear factor E2-related factor 2/Kelch-like ECH-related protein 1 may be the core link in its regulation of the expression of antioxidant enzyme to exert its antioxidant effect. What is confusing and interesting is that Sal B exhibits the opposite mechanisms in tumors. To clarify the specific target of Sal B and the correlation between its regulation of oxidative stress and energy metabolism homeostasis will help to further understand its role in different pathological conditions, and provide a scientific basis for its further clinical application and new drug development. Although Sal B has broad prospects in clinical application due to its extensive pharmacological effects, the low bioavailability is a serious obstacle to further improving its efficacy in vivo and promoting clinical application. Therefore, how to improve the availability of Sal B in vivo requires the joint efforts of many interdisciplinary subjects.

TLR4-MyD88 signaling pathway is responsible for acute lung inflammation induced by reclaimed water

Previous research found that inhalation exposure of reclaimed water could cause severe pulmonary inflammation, and the endotoxin was proposed to be the key risk factor. To further support this view, the toxic effects of different reclaimed water induced by acute inhalation exposure were compared between wildtype C57BL/6J and TLR4 signaling pathway defect mice. It was found that reclaimed water with high levels of endotoxin could induce strong inflammation in wildtype mice, but not in Tlr4^-/- and MyD88^-/- mutants. The mixed bacterial culture from the reclaimed water showed very weak response in wildtype mice and no response in TLR4-signaling pathway deficient mice, which further suggested that the cell-bound endotoxins contribute little in the inflammation induced by reclaimed water. In addition, conditional knockout of the Tlr4 gene in myeloid cells resulted in a significant reduction of sensitivity to the reclaimed water in mutants, which indicates that myeloid cells play the most important role in the defensive immune system against the pollutants in the water. In general, this study demonstrated that the TLR4-MyD88 signaling pathway is responsible for the acute lung inflammation induced by reclaimed water, which excludes the possibility of other signaling pathway dependent inflammation inducers in reclaimed water.

Andrade-Oliveira Salvianolic Acid B Modulates Caspase-1-Mediated Pyroptosis in Renal Ischemia-Reperfusion Injury via Nrf2 Pathway

Acute kidney injury (AKI) is a serious disease characterized by a rapid decline in kidney function. Oxidative stress is the primary pathogenesis of AKI. Salvianolic acid B (SalB), a water-soluble compound extracted from Salvia miltiorrhiza, possesses a potent antioxidant activity. Here, we investigated the protective effect of SalB against renal ischemia-reperfusion injury (I/R) in mice. Briefly, by analyzing renal function, oxidative stress markers and inflammatory biomarkers, we found that SalB could improve kidney damage, reduce oxidative stress and inflammatory factor levels. Interestingly, the expression of the NLR family pyrin domain-containing 3 (NLRP3), caspase-1, pyroptosis related proteins gasdermin D (GSDMD) and interleukin (IL)-1β, which were significantly upregulated in the kidney tissues of I/R group, was effectively reversed by SalB. Meanwhile, renal tubular epithelial cells hypoxia and reoxygenation model was used to explore pyroptosis of caspase-1-dependent. Further mechanism study showed that the SalB pretreatment could promote the increase of nuclear factor erythroid-2 related factor 2 (Nrf2) nuclear accumulation, which significantly suppressed oxidative stress, proinflammatory cytokines, NLRP3 inflammasome activation and pyroptosis. These results indicate that SalB can inhibit caspase-1/GSDMD-mediated pyroptosis by activating Nrf2/NLRP3 signaling pathway, resulting in alleviating I/R injury in mice.

Salvianolic Acid D Alleviates Cerebral Ischemia-Reperfusion Injury by Suppressing the Cytoplasmic Translocation and Release of HMGB1-Triggered NF-κB Activation to Inhibit Inflammatory Response

Inflammatory response participates in the overall pathophysiological process of stroke. It is a promising strategy to develop antistroke drugs targeting inflammation. This study is aimed at investigating the therapeutic effect and anti-inflammatory mechanism of salvianolic acid D (SalD) against cerebral ischemia/reperfusion (I/R) injury. A rat middle cerebral artery occlusion/reperfusion (MCAO/R) injury model was established, and an oxygen-glucose deprivation/reoxygenation (OGD/R) injury model was established in PC12 cells. Neurological deficit score, cerebral infarction, and edema were studied in vivo. Cell viability was achieved using the MTT method in vitro. The Bax, Bcl-2, cytochrome c, HMGB1, TLR4, TRAF6, NF-κB p65, p-NF-κB p65, and cleaved caspase-3 and -9 were tested via the Western blot method. Cytokines and cytokine mRNA, including TNF-α, IL-1β, and IL-6, were studied via ELISA and PCR methods. The translocation of HMGB1 and NF-κB were studied by immunofluorescence assay. The HMGB1/NeuN, HMGB1/GFAP, and HMGB1/Iba1 double staining was carried out to observe the localization of HMGB1 in different cells. Results showed that SalD alleviated neurological impairment, decreased cerebral infarction, and reduced edema in I/R rats. SalD improved OGD/R-downregulated PC12 cell viability. SalD also promoted Bcl-2 expression and suppressed Bax, cytochrome c, and cleaved caspase-3 and -9 expression. SalD decreased the intensity of TLR4, MyD88, and TRAF6 proteins both in vivo and in vitro, and significantly inhibited the NF-κB nuclear translocation induced by I/R and OGD/R. What's more, SalD inhibited HMGB1 cytoplasmic translocation in neurons, astrocytes, and microglia in both the cortex and hippocampus regions of I/R rats. In conclusion, SalD can alleviate I/R-induced cerebral injury in rats and increase the PC12 cell viability affected by OGD/R. The anti-inflammatory mechanism of SalD might result from the decreased nuclear-to-cytoplasmic translocation of HMGB1 and the inhibition on its downstream TLR4/MyD88/NF-κB signaling.

Plant-Derived Molecules α-Boswellic Acid Acetate, Praeruptorin-A, and Salvianolic Acid-B Have Age-Related Differential Effects in Young and Senescent Human Fibroblasts In Vitro

Testing and screening of plant-derived molecules on normal human cells in vitro is a widely used approach for discovering their eventual health beneficial effects for human ageing and longevity. As little is known about age-associated differential effects of such molecules, here we report that young (<25% replicative lifespan completed) and near-senescent (>90% replicative lifespan completed) human skin fibroblasts exposed for 1–15 days to a wide range of concentrations (0.1–100 μM) of the three selected phytochemicals, namely α-boswellic acid acetate (ABC), praeruptorin-A (PTA), and salvianolic acid-B (SAB) had age-related differential effects. The parameters studied were the metabolic activity (MTT assay), cellular morphological phenotype, one-step growth characteristics, expression of genes involved in the cell cycle regulation and cytokine network genes, protein levels of p53, cytosolic superoxide dismutase (SOD1) and microtubule-associated protein 1A/1B-light chain 3 (LC3), and the extent of protein carbonylation and protein aggregation as a sign of oxidative stress. All three compounds showed biphasic hormetic dose response by stimulating cell growth, survival and metabolic activity at low doses (up to 1 μM), while showing inhibitory effects at high doses (>10 μM). Furthermore, the response of early passage young cells was different from that of the late passage near-senescent cells, especially with respect to the expression of cell cycle-related and inflammation-related genes. Such studies have importance with respect to the use of low doses of such molecules as health-promoting and/or ageing-interventions through the phenomenon of hormesis.

Salvianolic acid B protects against myocardial ischaemia-reperfusion injury in rats via inhibiting high mobility group box 1 protein expression through the PI3K/Akt signalling pathway

Salvianolic acid B (Sal B) has a significant protective effect on myocardial ischaemia-reperfusion (I/R) injury. Therefore, the aims of this study were to determine the effects of Sal B on myocardial ischaemic-reperfusion (I/R) injury in rats and to explore whether its underlying mechanism of cardioprotection occurs through activating the expression of the phosphoinositide 3-kinase/protein, kinase B (PI3K/Akt) and inhibiting the expression of high mobility group protein 1 (HMGB1). Ninety Sprague-Dawley rats were randomized into five groups: group 1 (sham-operated), group 2 (myocardial I/R), group 3 (low dose of Sal B+I/R), group 4 (high dose of Sal B+I/R), and group 5 (high dose of Sal B+I/R+LY294002, which is a specific PI3k inhibitor). All I/R rats received 30 min myocardial ischaemia followed by 24-h reperfusion. Cardiac function, infarct size, myocardial injury marker levels, inflammatory response and cardiomyocyte apoptosis as well as Bcl-2, Bax, P-Akt, HMGB1 and TLR4 expression were measured. In the current study, Sal B significantly ameliorated myocardial I/R injury in a dose-dependent manner, ameliorated cardiac function, reduced myocardial infarction size, decreased myocardial injury marker expression, decreased inflammatory responses, reduced apoptosis, activated PI3K/Akt expression and inhibited HMGB1 expression. However, all effects of Sal B were significantly reversed by LY294002. Overall, the present study indicated that Sal B attenuated myocardial I/R injury by activating PI3K/Akt and inhibiting the release of HMGB1 in rats.

Dipeptidyl Peptidase-4 (DPP-4) Inhibitor Saxagliptin Alleviates Lipopolysaccharide-Induced Acute Lung Injury via Regulating the Nrf-2/HO-1 and NF-B Pathways

PURPOSE

We aimed at investigating the effects of Dipeptidyl peptidase-4 (DPP-4) inhibitor saxagliptin (Saxa) on mouse acute lung injury (ALI)-induced by lipopolysaccharide (LPS) and the potential mechanisms.

MATERIALS/METHODS

Animals were divided into four groups: control, Saxa, LPS, and LPS + Saxa. Histopathology changes of lung tissues were assessed by hematoxylin and eosin staining and periodic acid-Schiff staining. The degree of edema was determined by wet/dry ratio. The levels of oxidative stress markers and inflammatory cytokines in lung homogenate and bronchoalveolar lavage fluid were detected using kits. Terminal deoxynucleotidyl transferase dUTP nick end labeling assay was used to test apoptosis and Western blotting was applied to measure the expression of apoptosis-associated proteins. The expression of nuclear factor erythroid 2-related factor 2 (Nrf-2)/heme oxygenase-1 (HO-1) and nuclear factor-kappa B (NF-κB) pathways were detected by Western blotting.

RESULTS

The results revealed that Saxa attenuated LPS-induced pathological injury and edema. Saxa decreased the levels of reactive oxygen species (ROS), malondialdehyde (MDA), myeloperoxidase (MPO) and increased the levels of superoxide dismutase (SOD) and catalase (CAT). The contents of inflammatory cytokines were reduced in the Saxa intervention group. Saxa attenuated apoptosis accompanied by alterations in the expression of apoptosis-associated proteins. Furthermore, the expression of Nrf-2 and HO-1 were upregulated whereas phospho (p)-NF-κB p65 and phospho-inhibitory subunit of NF-κB alpha (p-IκB-α) were downregulated after Saxa treatment.

CONCLUSION

These findings concluded that Saxa alleviates oxidative stress, inflammation and apoptosis in ALI induced by LPS via modulating the Nrf-2/HO-1 and NF-κB pathways, which provides evidence for employing Saxa in ALI treatment.

Safety Evaluation of a New Traditional Chinese Medical Formula, Ciji-Hua'ai-Baosheng II Formula, in Adult Rodent Models

Background

Ciji-Hua'ai-Baosheng II Formula (CHB-II-F) is a new traditional Chinese medical formula that has been shown to reduce toxicity and side effects of chemotherapy and increase the probability of cancer patient survival. Whether CHB-II-F is safe as an adjunctive therapy for cancer patients receiving chemotherapy has yet to be determined.

Purpose

To evaluate the acute and subchronic toxic effects of CHB-II-F in rodent models.

Methods

In acute toxicity test, 24 Kunming mice were divided into 2 groups: untreated control and CHB-II-F 1.05 g/mL (31.44 g/kg) treated group. Treatment was administered to the treated group 3 times a day for 14 days. The overall health, adverse reactions, and mortality rate were documented. In subchronic toxicity test, 96 Sprague-Dawley rats were divided into 4 groups: untreated control, high dose CHB-II-F (H) (26.20 g/kg), medium dose CHB-II-F (M) (13. 10 g/kg), and low dose CHB-II-F (L) (6.55 g/kg) [equal to 24.375 g (dried medicinal herb)/kg] treated groups. Treated groups were given the treatments once a day for 4 weeks. The overall health and mortality rate were recorded every day. Body weight and food consumption were measured once a week. Hematologic and biochemical parameters, organ weights, and histopathologic markers were analyzed after 4 weeks. An additional 2 weeks were given as the treatment recovery period before end-point euthanization, and biochemical analyses were performed.

Results

The maximum tolerated dose (MTD) of CHB-II-F on mice was found to be 94.31 g/kg [equal to 351 g (dried medicinal herb)/kg], which is 108 times the human adult dose. In the acute toxicity test, administration of CHB-II-F 31.44 g/kg showed no adverse effect and did not cause mortality. In the subchronic toxicity test, after 4 weeks of treatment, compared to the controls, total cholesterol (TCHO) level, cardiac and splenic indexes, body weights of female rats, and mean corpuscular hemoglobin concentration (MCHC) in the CHB-II-F (H) group were significantly increased; triglyceride (TG) in the CHB-II-F (M) group and liver and splenic indexes in the CHB-II-F (L) group were increased. After the two-week recovery period, biofluid analyses, food consumption, and histopathologic examinations showed no abnormalities.

Conclusion

Administration of CHB-II-F had no obvious adverse effect on the overall health of rodent models. A daily maximum dose of less than 94.31 g/kg or 6.55 g/kg CHB-II-F for 4 continuous weeks was considered safe.

Effects of BSF on Podocyte Apoptosis via Regulating the ROS-Mediated PI3K/AKT Pathway in DN

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease (ESRD). The ROS-mediated PI3K/AKT pathway plays a key role in podocyte apoptosis and DN progression. Our previous study demonstrated that Baoshenfang (BSF) can decrease proteinuria and attenuate podocyte injury. However, the effects of BSF on podocyte apoptosis induced by the ROS-mediated PI3K/AKT pathway remain unclear. Herein, in vivo and in vitro studies have been performed. In our in vivo study, BSF significantly decreased 24-h urinary protein, serum creatinine, and blood urea nitrogen levels in DN mice. Meanwhile, BSF significantly inhibited oxidative stress and podocyte apoptosis in our in vivo and in vitro studies. Moreover, BSF significantly decreased the inhibition of the PI3K/AKT pathway induced by HG in DN. More importantly, the effects of BSF on podocyte apoptosis were reversed by PI3K siRNA transfection. In conclusion, BSF can decrease proteinuria and podocyte apoptosis in DN, in part through regulating the ROS-mediated PI3K/AKT pathway.

Effect of Baoshenfang Formula on Podocyte Injury via Inhibiting the NOX-4/ROS/p38 Pathway in Diabetic Nephropathy

Diabetic nephropathy (DN) is a serious kidney-related complication of type 1 and type 2 diabetes. The Chinese herbal formula Baoshenfang (BSF) shows therapeutic potential in attenuating oxidative stress and apoptosis in podocytes in DN. This study evaluated the effects of BSF on podocyte injury in vivo and in vitro and explored the possible involvement of the nicotinamide adenine dinucleotide phosphate-oxidase-4/reactive oxygen species- (NOX-4/ROS-) activated p38 pathway. In the identified compounds by mass spectrometry, some active constituents of BSF were reported to show antioxidative activity. In addition, we found that BSF significantly decreased 24-hour urinary protein, serum creatinine, and blood urea nitrogen in DN patients. BSF treatment increased the nephrin expression, alleviated oxidative cellular damage, and inhibited Bcl-2 family-associated podocyte apoptosis in high-glucose cultured podocytes and/or in diabetic rats. More importantly, BSF also decreased phospho-p38, while high glucose-mediated apoptosis was blocked by p38 mitogen-activated protein kinase inhibitor in cultured podocytes, indicating that the antiapoptotic effect of BSF is p38 pathway-dependent. High glucose-induced upexpression of NOX-4 was normalized by BSF, and NOX-4 siRNAs inhibited the phosphorylation of p38, suggesting that the activated p38 pathway is at least partially mediated by NOX-4. In conclusion, BSF can decrease proteinuria and protect podocytes from injury in DN, in part through inhibiting the NOX-4/ROS/p38 pathway.

Salvianolic acid B as an anti-emphysema agent I: In vitro stimulation of lung cell proliferation and migration, and protection against lung cell death, and in vivo lung STAT3 activation and VEGF elevation

Emphysema causes progressive and life-threatening alveolar structural destruction/loss, yet remains irreversible and incurable to date. Impaired vascular endothelial growth factor (VEGF) signaling has been proposed as a new pathogenic mechanism, and if so, VEGF recovery may enable reversal of emphysema. Thus, we hypothesized that salvianolic acid B (Sal-B), a polyphenol in traditional Chinese herbal danshen, is an alveolar structural recovery agent for emphysema by virtue of VEGF stimulation/elevation via activation of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3), as stimulating lung cell proliferation and migration, and protecting against lung cell death. Using in vitro human lung microvascular endothelial (HMVEC-L) and alveolar epithelial (A549) cell systems, Sal-B was examined for 1) stimulation of cell proliferation by the MTT and BrdU assays; 2) promotion of cell migration by the scratch wound closure assay; 3) protection against emphysema-like induced cell death by the trypan blue exclusion and flow cytometry assays; and 4) mechanistic involvement of JAK2/STAT3/VEGF in these activities. Sal-B was also spray-dosed to the lungs of healthy rats for two weeks to verify the lung's STAT3 activation and VEGF elevation by western blot, as well as the absence of functional and morphological abnormalities. All the in vitro cell-based activities were concentration-dependent. At 25 μM, Sal-B 1) stimulated cell proliferation by 1.4-2.6-fold; 2) promoted migratory cell wound closure by 1.5-1.7-fold; and 3) protected against cell death induced with H₂O₂ (oxidative stress) and SU5416 (VEGF receptor blockade) by 49-86%. JAK2 and STAT3 inhibitors and VEGF receptor antagonist each opposed these Sal-B's activities by over 65%, suggesting the mechanistic involvement of JAK2/STAT3 activation and VEGF stimulation/elevation. In rats, Sal-B at 0.2 mg/kg enabled 1.9 and 1.5-fold increased STAT3 phosphorylation and VEGF elevation in the lungs, respectively, while causing no functional and morphological abnormalities. Hence, Sal-B was projected to be a new class of anti-emphysema agent capable of reversing alveolar structural destruction/loss via JAK2/STAT3/VEGF-dependent stimulation of lung cell proliferation and migration, and inhibition of induced lung cell death.

Salvianolic acid B as an anti-emphysema agent II: In vivo reversal activities in two rat models of emphysema

Emphysema progressively destroys alveolar structures, leading to disability and death, yet remains irreversible and incurable to date. Impaired vascular endothelial growth factor (VEGF) signaling is an emerging pathogenic mechanism, thereby proposing a hypothesis that VEGF stimulation/elevation enables recovery from alveolar structural destruction and loss of emphysema. Our previous in vitro study identified that salvianolic acid B (Sal-B), a polyphenol of traditional Chinese herbal danshen, stimulated lung cell proliferation and migration, and protected against induced lung cell death, by virtue of signal transducer and activator of transcription 3 (STAT3) activation and VEGF stimulation/elevation. Thus, this study examined Sal-B for in vivo therapeutic reversal of established emphysema in two rat models. Emphysema was induced with porcine pancreatic elastase (PPE) and cigarette smoke extract (CSE), and established by day 21. Sal-B was then spray-dosed to the lung three times weekly for three weeks. Functional treadmill exercise endurance; morphological airspace enlargement and alveolar destruction; apoptosis, cell proliferation and tissue matrix proteins; phosphorylated STAT3 (pSTAT3) and VEGF expressions; neutrophil accumulation; and lipid peroxidation were determined. In both models, Sal-B at 0.2 mg/kg significantly reversed impaired exercise endurance by 80 and 64%; airspace enlargement [mean linear intercept (MLI)] by 56 and 67%; and alveolar destructive index (%DI) by 63 and 66%, respectively. Induced apoptosis activity [cleaved caspase-3] was normalized by 94 and 82%; and cell proliferation activity [proliferative cell nuclear antigen (PCNA)] was stimulated by 1.6 and 2.1-fold. In the PPE-induced model, Sal-B reduced induction of lung's matrix metalloproteinase (MMP)-9 and MMP-2 activities by 59 and 94%, respectively, and restored pSTAT3 and VEGF expressions to the healthy lung levels, while leaving neutrophil accumulation unchecked [myeloperoxidase (MPO) activity]. In the CSE-induced model, Sal-B elevated pSTAT3 and VEGF expressions both by 1.8-fold over the healthy lung levels, and normalized induced lipid peroxidation [malondialdehyde (MDA) activity] by 68%. These results provide an in vivo proof-of-concept for Sal-B as one of the first anti-emphysema agents enabling reversal of alveolar structural destruction and loss via local lung treatment by virtue of its STAT3 activation and VEGF stimulation.

Retracted Article: Salvianolic acid B inhibits inflammatory response and cell apoptosis via the PI3K/Akt signaling pathway in IL-1β-induced osteoarthritis chondrocytes

Osteoarthritis (OA) is the most common joint disease among late middle-aged or elderly people. The pathological process of OA mainly involves the degeneration of cartilage tissue and deficiency of joint function. Salvianolic acid B (Sal B) is the main active ingredient of Salvia miltiorrhiza Bge, which possesses anti-inflammatory, anti apoptotic and other pharmacological activities. In this study, primary chondrocytes were cultured to investigate the effects of Sal B on the inflammatory response and apoptosis of OA induced by IL-1β, and to explore the possible mechanism. First, we determined the cytotoxicity of Sal B; the results showed that the cell activity of chondrocytes was not influenced by Sal B when the concentration was below 150 μM. Moreover, Sal B (40 and 80 μM) suppressed the expression of iNOS in OA chondrocytes induced by IL-1β, and restrained the secretion of NO, IL-6, IL-17 and TNF-α in chondrocytes obviously. Sal B (40, 80 μM) significantly alleviated the inhibitory effect of cell activity stimulated by IL-1β and up-regulated the expression of Col II and reduced the expression of Col X. Besides, Sal B down-regulated the expression level of Bax and promoted the expression of Bcl-2, showed a significant effect on promoting proliferation and inhibiting cell apoptosis. In addition, we found that IL-1β significantly reduced the ratio of p-PI3K/PI3K, p-Akt/Akt induced the nuclear translocation of AKT and inhibited the activation of the PI3K/Akt signaling pathway. Finally, the PI3K inhibitor, LY-294002, was added in IL-1β-induced chondrocytes. The results suggest that Sal B ameliorates IL-1β induced inflammation and suppresses apoptosis in OA by activating the PI3K/Akt signaling pathway. Our study reveals the mechanism of Sal B acts on OA and may provide a basis for the treatment of OA with Sal B.

Osteoarthritis (OA) is the most common joint disease among late middle-aged or elderly people.