Molecular regulation of autophagy and suppression of protein kinases by aescin, a triterpenoid saponin impedes lung cancer progression.

Lung cancer is the most common and lethal cancer worldwide, yet there are no adequate and novel medications to control this illness. Previous reports suggested the potential of protein kinases to target lung cancer by regulating autophagy. This study establishes the role of aescin, a triterpenoid saponin, in targeting protein kinases responsible for lung cancer proliferation and mobility. The experimental data revealed that aescin significantly impedes lung cancer cell proliferation by downregulating protein kinases such as AKT, mTOR, MEK, and ERK. Downregulation of AKT-mTOR may promote a string of events inducing cytotoxic autophagy-mediated apoptosis in the presence of aescin. Besides, aescin decreases mobility and invasion by downregulating HIF-1α and VEGF gene expressions. Moreover, it successfully monitors EGFR gene expression, improves lung histology, and regulates biochemical parameters in a pre-clinical DEN-induced lung cancer model. Aescin was observed to be safe and non-toxic in both in silico toxicity predictions and ex vivo erythrocyte fragility assays. Hence, this study elucidates the molecular mechanism of aescin in targeting protein kinases and suggests that it could be a safer and more viable therapeutic agent for lung cancer treatment.

Escin's Multifaceted Therapeutic Profile in Treatment and Post-Treatment of Various Cancers: A Comprehensive Review.

Although modern medicine is advancing at an unprecedented rate, basic challenges in cancer treatment and drug resistance remain. Exploiting natural-product-based drugs is a strategy that has been proven over time to provide diverse and efficient approaches in patient care during treatment and post-treatment periods of various diseases, including cancer. Escin-a plant-derived triterpenoid saponin-is one example of natural products with a broad therapeutic scope. Initially, escin was proven to manifest potent anti-inflammatory and anti-oedematous effects. However, in the last two decades, other novel activities of escin relevant to cancer treatment have been reported. Recent studies demonstrated escin's efficacy in compositions with other approved drugs to accomplish synergy and increased bioavailability to broaden their apoptotic, anti-metastasis, and anti-angiogenetic effects. Here, we comprehensively discuss and present an overview of escin's chemistry and bioavailability, and highlight its biological activities against various cancer types. We conclude the review by presenting possible future directions of research involving escin for medical and pharmaceutical applications as well as for basic research.

Anti-obesity effect of escin: a study on high-fat diet-induced obese mice.

OBJECTIVE: Obesity is characterized by excess fat accumulation and closely associated with insulin resistance and type 2 diabetes. We aimed at exploring the potential effect and mechanism of escin for the treatment of obesity using network pharmacology, and to verify the effect of escin on obese mice. MATERIALS AND METHODS: Escin targets were predicted by DrugBank and SwissTarget database. Potential targets for the treatment of obesity were identified based on the DisGeNET database. Comparative analysis was used to investigate the overlapping genes between escin targets and obesity treatment-related targets. Using STRING database and Cytoscape to analyze interactions among overlapping genes, hub genes were identified. Gene Ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were conducted in DAVID. High-fat diet (HFD) -induced obese mice were used to observe the anti-obesity effects of escin. The body weight, relevant biochemical markers and HE staining of fat and liver tissues were determined after escin was administered for 18 weeks. RESULTS: We screened 53 overlapping genes for escin and obesity. The mechanism of intervention of escin in treating obesity may involve 10 hub targets (STAT3, MTOR, NR3C1, IKBKB, PTGS2, MMP9, PRKCA, PRKCD, AR, CYP3A4). The screening and enrichment analysis revealed that the treatment of obesity using escin primarily involved 10 GO enriched terms and 13 related pathways. In vivo, escin can reduce the body weight of obese mice induced by HFD and improve lipid metabolism through lowering triglycerides (TG), total cholesterol (TC), and density lipoprotein (LDL) levels and increasing high density lipoprotein (HDL) levels and decreasing leptin level and increasing adiponectin (ADPN) level. Escin can regulate glucose metabolism caused by obesity through decreasing fasting glucose, postprandial blood glucose and regulating the level of insulin. These obese mice induced by HFD displayed the increased insulin resistance that was associated with the increased inflammatory cytokines, including interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and monocyte chemoattractant protein-1 (MCP-1). Escin may antagonize the increase of MCP-1 and partially antagonize the low-grade inflammation caused by obesity. From the morphological changes of fat and liver tissues stained by HE stain, escin could decrease the size of adipocytes and improve liver necrosis and fatty degeneration in obese mice fed by HFD. CONCLUSIONS: The network pharmacology of escin in treating obesity may involve 10 hub targets (STAT3, MTOR, NR3C1, IKBKB, PTGS2, MMP9, PRKCA, PRKCD, AR, CYP3A4), 10 GO enriched terms and 13 related pathways. In vivo, escin can be potentially used to prevent or treat obesity through reducing the weight, improving glucose and lipid metabolism, partially antagonizing the low-grade inflammation, and improved insulin resistance.

Escin inhibits angiogenesis by suppressing interleukin­8 and vascular endothelial growth factor production by blocking nuclear factor­κB activation in pancreatic cancer cell lines.

Pancreatic cancer (PaCa) is one of the most aggressive types of cancer. Thus, the development of new and more effective therapies is urgently required. Escin, a pentacyclic triterpenoid from the horse chestnut, has been reported to exhibit antitumor potential by reducing cell proliferation and blocking the nuclear factor­κB (NF­κB) signaling pathway in several types of cancer. Our previous study reported that NF­κB enhanced the secretion of interleukin (IL)­8 and vascular endothelial growth factor (VEGF), thereby inducing angiogenesis in PaCa cell lines. In the present study, it was examined whether escin inhibited angiogenesis by blocking NF­κB activation in PaCa. It was initially confirmed that escin, at concentrations >10 µM, significantly inhibited the proliferation of several PaCa cell lines. Next, using immunocytochemical staining, it was found that escin inhibited the nuclear translocation of NF­κB. Furthermore, ELISA confirmed that NF­κB activity in the escin­treated PaCa cells was significantly inhibited and reverse transcription­quantitative PCR showed that the mRNA expression levels of tumor necrosis factor­α­induced IL­8 and VEGF were significantly suppressed following escin treatment in the PaCa cell lines. ELISA also showed that escin decreased the secretion of IL­8 and VEGF from the PaCa cells. Furthermore, tube formation in immortalized human endothelial cells was inhibited following incubation with the supernatants from escin­treated PaCa cells. These results indicated that escin inhibited angiogenesis by reducing the secretion of IL­8 and VEGF by blocking NF­κB activity in PaCa. In conclusion, escin could be used as a novel molecular therapy for PaCa.

Attenuation of Cardiac Autonomic Neuropathy by Escin in Diabetic Rats.

Cardiac autonomic neuropathy (CAN) is a least diagnosed complication of diabetes. Inflammation and oxidative stress play a crucial role in the pathophysiology of cardiomyopathy and neuropathy. Escin has anti-inflammatory activity and antioxidant activity. Hence, the present study was designed to evaluate the effect of escin in the management of CAN. Diabetes was induced in Sprague Dawley rats with streptozotocin (STZ). Diabetic animals were randomized in different groups after 6 weeks. Animals in the diabetic control group received no treatment, while animals in other groups received escin at dose 5, 10, and 20 mg/kg for 4 weeks. One group was kept as normal control. Various parameters like basic hemodynamic parameters, heart rate variability (HRV), oxidative stress parameters, and matrix metalloproteinase 9 (MMP-9) were assessed at the end of study. Escin significantly normalized hemodynamic parameters and HRV as compared to diabetic animals. Escin significantly reduced the malondialdehyde level and significantly increased reduced glutathione, catalase and superoxide dismutase levels in diabetic animals. Escin treatment significantly reduced plasma MMP-9 level in diabetic rats. The improvement in the studied parameters was found mainly with administration of higher doses of escin (10 and 20 mg/kg). The escin treatment mitigates CAN in diabetic rats. The results of study indicate that escin can be useful option for management of CAN.

[Escin alleviates chemotherapy-induced peripheral neuropathic pain by inducing autophagy in the spinal cord of rats].

OBJECTIVE: To investigate the effect of escin in relieving chemotherapy-induced peripheral neuropathic pain in rats and explore and the underlying mechanism. METHODS: Eighteen SD rats were randomly divided into 3 groups (n=6), including an escin preconditioning group (treated with 4 mg/kg escin on days 1-7 and then with 2 mg/kg taxol on days 8, 10, 12, and 14), an escin postconditioning group (treated with 2 mg/kg taxol on days 1, 3, 5, and 7 and then with 4 mg/mg escin on days 8-14) and control group (treated with 2 mg/kg taxol on days 1, 3, 5, and 7 and then with saline on days 8-14). Mechanical allodynia and thermal hyperalgesia of the mice were tested on days 4, 7, 10 and 14, and the expression levels of LC3II and p62 in the spinal cord of the rats were detected using Western blotting. RESULTS: The rats in both the escin preconditioning group and escin postconditioning group showed obviously increased thresholds of mechanical allodynia and thermal hyperalgesia as compared with those in the control group (P < 0.01). Western blotting showed that the expression level of LC3II was significantly increased while p62 expression was lowered in escin preconditioning group as compared with those in the control group (P < 0.05). The escin postconditioning group also showed significantly higher LC3II expression and lower p62 expression levels than the control group (P < 0.05). CONCLUSIONS: Escin can alleviate chemotherapy-induced peripheral neuropathic pain in rats possibly by upregulating the expressions of autophagy-related proteins in the spinal cord.

Inhibition of Migration and Invasion in Melanoma Cells by ß-Escin via the ERK/NF-κB Signaling Pathway.

ß-Escin, a natural triterpene saponin was extracted from Aesculus hippocastanum seeds, which have been widely used to treat inflammation in traditional medicine. In an effort to study the possible anti-tumor effects of ß-escin, we performed wound healing, invasion, and adhesion assays to examine the effects of ß-escin on cell migration, invasion, and angiogenesis. Our results revealed that ß-escin inhibits cell migration as well as motility in B16F10 and SK-MEL5 cells in a dose-dependent manner. RT-PCR and Western blot analysis showed that ß-escin increased TIMP-1, -2 while significantly downregulated phosphorylated extracellular signal-regulated kinase (p-ERK) expression, and suppressing nuclear factor-kappa B (NF-κB) and inhibitor of nuclear factor-kappa B (IκB) expression. Overall, the data from the current study suggest that ß-escin has the potential for inhibiting both metastatic and angiogenic activities, and are the earliest evidence for the involvement of the NF-κB/IκB signaling in ß-escin-induced anti-tumor effects.

Escin-induced DNA damage promotes escin-induced apoptosis in human colorectal cancer cells via p62 regulation of the ATM/γH2AX pathway.

Escin, a triterpene saponin isolated from horse chestnut seed, has been used to treat encephaledema, tissue swelling and chronic venous insufficiency. Recent studies show that escin induces cell cycle arrest, tumor proliferation inhibition and tumor cell apoptosis. But the relationship between escin-induced DNA damage and cell apoptosis in tumor cells remains unclear. In this study, we investigated whether and how escin-induced DNA damage contributed to escin-induced apoptosis in human colorectal cancer cells. Escin (5-80 µg/mL) dose-dependently inhibited the cell viability and colony formation in HCT116 and HCT8 cells. Escin treatment induced DNA damage, leading to p-ATM and γH2AX upregulation. Meanwhile, escin treatment increased the expression of p62, an adaptor protein, which played a crucial role in controlling cell survival and tumorigenesis, and had a protective effect against escin-induced DNA damage: knockdown of p62 apparently enhanced escin-induced DNA damage, whereas overexpression of p62 reduced escin-induced DNA damage. In addition, escin treatment induced concentration- and time-dependent apoptosis. Similarly, knockdown of p62 significantly increased escin-induced apoptosis in vitro and produced en escin-like antitumor effect in vivo. Overexpression of p62 decreased the rate of apoptosis. Further studies revealed that the functions of p62 in escin-induced DNA damage were associated with escin-induced apoptosis, and p62 knockdown combined with the ATM inhibitor KU55933 augmented escin-induced DNA damage and further increased escin-induced apoptosis. In conclusion, our results demonstrate that p62 regulates ATM/γH2AX pathway-mediated escin-induced DNA damage and apoptosis.

Aescin-induced reactive oxygen species play a pro-survival role in human cancer cells via ATM/AMPK/ULK1-mediated autophagy.

Aescin, a natural mixture of triterpene saponins, has been reported to exert anticancer effect. Recent studies show that aescin increases intracellular reactive oxygen species (ROS) levels. However, whether the increased ROS play a role in the anticancer action of aescin remains to be explored. In this study, we demonstrated that aescin (20-80 µg/mL) dose-dependently induced apoptosis and activated mammalian target of rapamycin (mTOR)-independent autophagy in human hepatocellular carcinoma HepG2 cells and colon carcinoma HCT 116 cells. The activation of autophagy favored cancer cell survival in response to aescin, as suppression of autophagy with ATG5 siRNAs or 3-methyladenine (3-MA), a selective inhibitor of autophagy, promoted aescin-induced apoptosis in vitro, and significantly enhanced the anticancer effect of aescin in vivo. Meanwhile, aescin dose-dependently elevated intracellular ROS levels and activated Ataxia-telangiectasia mutated kinase/AMP-activated protein kinase/UNC-51-like kinase-1 (ATM/AMPK/ULK1) pathway. The ROS and ATM/AMPK/ULK1 pathway were upstream modulators of the aescin-induced autophagy, as N-acetyl-L-cysteine (NAC) or ATM kinase inhibitor (KU-55933) remarkably suppressed aescin-induced autophagy and consequently promoted aescin-induced apoptosis, whereas overexpression of ATG5 partly attenuated NAC-induced enhancement in aescin-induced apoptosis. In conclusion, this study provides new insights into the roles of aescin-mediated oxidative stress and autophagy in cancer cell survival. Our results suggest that combined administration of the antioxidants or autophagic inhibitors with aescin might be a potential strategy to enhance the anticancer effect of aescin.

Molecular targets and anti-cancer potential of escin.

Escin is a mixture of triterpenoid saponins extracted from the horse chestnut tree, Aesculus hippocastanum. Its potent anti-inflammatory and anti-odematous properties makes it a choice of therapy against chronic venous insufficiency and odema. More recently, escin is being actively investigated for its potential activity against diverse cancers. It exhibits anti-cancer effects in many cancer cell models including lung adenocarcinoma, hepatocellular carcinoma and leukemia. Escin also attenuates tumor growth and metastases in various in vivo models. Importantly, escin augments the effects of existing chemotherapeutic drugs, thereby supporting the role of escin as an adjunct or alternative anti-cancer therapy. The beneficial effects of escin can be attributed to its inhibition of proliferation and induction of cell cycle arrest. By regulating transcription factors/growth factors mediated oncogenic pathways, escin also potentially mitigates chronic inflammatory processes that are linked to cancer survival and resistance. This review provides a comprehensive overview of the current knowledge of escin and its potential as an anti-cancer therapy through its anti-proliferative, pro-apoptotic, and anti-inflammatory effects.

The novel role of ß-aescin in attenuating CCl4-induced hepatotoxicity in rats.

CONTEXT: ß-Aescin has anti-inflammatory, anti-oxidant and antiedematous properties. OBJECTIVE: The present study investigated the hepatoprotective effect and underlying mechanisms of ß-aescin in CCl4-induced liver damage. MATERIALS AND METHODS: Thirty-five Wistar rats were divided into six groups: normal control, CCl4 control, silymarin (50 mg/kg, p.o) and ß-aescin (0.9, 1.8 and 3.6 mg/kg, i.p.) treatment for 14 d. CCl4 (1 mL/kg, i.p. for 3 d) was administered to produce hepatic damage. Ponderal changes and liver marker enzymes were estimated. Hepatic oxidative and nitrosative stress was estimated by levels of thiobarbituric acid reactive substances (TBARS), glutathione (GSH) and nitrite/nitrate. Serum TGF-ß1 and TNF-α were estimated by ELISA technique. Hepatic collagen and histopathological studies were carried out. RESULTS: ß-Aescin (3.6 mg/kg) markedly decreased CCl4-induced increased levels of ALT, AST, ALP (71.77 versus 206.7, 71.39 versus 171.82, 121.20 versus 259 IU/L, respectively), total bilirubin (0.41 versus 1.35 mg/dL), TBARS (2.0 versus 8.83 nmol MDA/mg protein), nitrite/nitrate (352.50 versus 745.15 µg/mL) and increased CCl4-induced decreased GSH levels (0.095 versus 0.048 µmol/mg protein). ß-Aescin (3.6 mg/kg) induced focal regenerative changes in liver and markedly decreased TBARS (2.0 versus 8.83 nmol MDA/mg protein), nitrite/nitrate (352.50 versus 745.15 µg/mL), TGF-ß1 (92.28 versus 152.1 pg/mL), collagen content (110.75 versus 301.74 µmol/100 mg tissue) and TNF-α (92.82 versus 170.56 pg/mL) when compared with CCl4 control. DISCUSSION AND CONCLUSION: The findings suggest that ß-aescin has a protective effect on CCl4-induced liver injury, exhibited via its anti-inflammatory, antioxidative, antinitrosative and antifibrotic properties inducing repair regeneration of liver. Hence, it can be used as a promising hepatoprotective agent.

Male infertility: lifestyle factors and holistic, complementary, and alternative therapies.

While we may be comfortable with an allopathic approach to male infertility, we are also responsible for knowledge about lifestyle modifications and holistic, complementary, and alternative therapies that are used by many of our patients. This paper provides an evidence-based review separating fact from fiction for several of these therapies. There is sufficient literature to support weight reduction by diet and exercise, smoking cessation, and alcohol moderation. Supplements that have demonstrated positive effects on male fertility on small randomized controlled trial (RCT) include aescin, coenzyme Q 10 , glutathione, Korean red ginseng, L-carnitine, nigella sativa, omega-3, selenium, a combination of zinc and folate, and the Menevit antioxidant. There is no support for the use of Vitamin C, Vitamin E, or saffron. The data for Chinese herbal medications, acupuncture, mind-body practice, scrotal cooling, and faith-based healing are sparse or inconclusive.

Combined treatment with low dose prednisone and escin improves the anti-arthritic effect in experimental arthritis.

The present study was aimed at investigating whether low dose oral prednisone combined with escin could inhibit the progression of adjuvant-induced arthritis (AIA) in rats. Adjuvant arthritis was induced in SD rats began day 1 for 28 days. Prednisone at doses of 2, 10 mg/kg/day alone or escin at doses of 5, 10 mg/kg/day alone, or prednisone at dose of 2 mg/kg/day with escin at doses of 5 or 10 mg/kg/day were given to different groups of rats intragastrically from day 13 to 28 respectively. Paw swelling, arthritic index, histological and radiographic changes were assessed to evaluate the anti-arthritic effect. Weight growth, spleen and thymus indexes were also calculated. Serum samples were collected for estimation of pro-inflammatory cytokines. Rats developed erosive arthritis of the hind paw when immunized with adjuvant. Prednisone 2 mg/kg combined with escin 5 or 10 mg/kg significantly inhibited the paw swelling. Histopathological and radiographic analysis showed a marked decrease of synovial inflammatory infiltration, synovial hyperplasia and bone erosion by combination therapy, which also markedly suppressed the expression of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6). No significant changes were found in monotherapy group except prednisone 10 mg/kg group. Furthermore, combined treatment rescued some of GCs' adverse effects evidenced by increase in body weight and decrease in index of spleen compared with untreated AIA rats. In conclusion, the combination therapy possessed synergistic anti-arthritic efficacy and reduced adverse effect, which may play a role in the management of human RA.

Escin Increases the Survival Rate of LPS-Induced Septic Mice Through Inhibition of HMGB1 Release from Macrophages.

BACKGROUND: Previous studies have described the effects of Escin on improving the survival rate of endotoxemic animals. The purpose of this study was to explore the molecular mechanisms of this potentially beneficial treatment. METHODS: First, the survival rate of endotoxemic mice was monitored for up to 2 weeks after Escin pretreatment, Escin post-treatment, or Escin post-treatment + rHMGB1. The effects of Escin on the release of pro-inflammatory cytokines such as TNF-α, IL-1ß, IL-6 and HMGB1 in the serum of endotoxemic mice and LPS-induced macrophages were evaluated by ELISA. Furthermore, the mRNA and protein levels of HMGB1 in LPS-induced macrophages were measured by qRT-PCR and Western blot, respectively. Additionally, the release of pro-inflammatory cytokines such as TNF-α, IL-1ß, IL-6 was evaluated by ELISA in rHMGB1-induced macrophages. Finally, the protein levels and the activity of NF-κB in macrophages were checked by Western blot and ELISA, respectively. RESULTS: Both pretreatment and post-treatment with Escin could improve the survival rate of endotoxemic mice, while exogenous rHMGB1 reversed this effect. In addition, Escin decreased the level of the pro-inflammatory cytokinesTNF-α,IL-1ß, IL-6 and HMGB1 in endotoxemic mice and in LPS-induced macrophages. Escin could also inhibit the mRNA levels and activity of HMGB1. The release of the pro-inflammatory cytokinesTNF-α,IL-1ß, IL-6 could be suppressed in rHMGB1-induced macrophages by Escin. Finally, Escin could suppress the activation of NF- κB in LPS-induced macrophages. CONCLUSION: Escin could improve the survival of mice with LPS-induced endotoxemia. This effect maybe meditated by reducing the release of HMGB1, resulting in the suppression of the release of pro-inflammatory cytokines.

Protective effects of escin against indomethacin-induced gastric ulcer in mice.

Escin, a natural mixture of triterpenoid saponin isolated from the seed of the horse chestnut, is reported to have a potent antiulcer activity against ethanol-induced gastric mucosal lesions. This study investigated the possible mechanisms underlying the gastroprotective effect of escin against indomethacin-induced gastric ulcer in mice. Gastric ulceration was induced by a single intragastric administration of indomethacin (18 mg/kg). The mice underwent intragastric treatment with escin at doses of 0.45, 0.9 or 1.8 mg/kg. Gastric lesion was estimated morphometrically and histopathologically 6 h after the indomethacin administration. The antioxidative parameters in gastric mucosa were measured. Moreover, the activity of myeloperoxidase and the contents of TNF-α, P-selectin and VCAM-1 in gastric tissues were determined. The results showed that escin protected gastric tissues against indomethacin-induced gastropathy as demonstrated from a reduction in the ulcer index and an attenuation of histopathologic changes. Escin caused significant reductions of the contents of malondialdehyde, TNF-α, P-selectin, VCAM-1 and myeloperoxidase activity. The altered activities of superoxide dismutase, catalase and glutathione peroxidase in the stomach tissues were also ameliorated by escin treatment. The present study demonstrated that escin had a protective effect against indomethacin-induced gastric ulcer in mice, not only by virtue of its antioxidant potential, but also due to its anti-inflammatory effect.

Cytotoxic effects of four aescin types on human colon adenocarcinoma cell lines.

Four types of aescin that are available on the pharmaceutical market, beta-aescin crystalline, beta-aescin amorphous, beta-aescin sodium and aescin polysulfate, have been analyzed for their cytotoxic effects on human colon adenocarcinoma (LoVo) and doxorubicin-resistant human colon adenocarcinoma cell lines (LoVo/Dx). Their cytotoxic activities were evaluated by sulforhodamine B (SRB) and methyl tetrazolium (MTT) assays. All four types of aescin exerted strong dose-dependent cytotoxicity to LoVo and, to a lesser degree, LoVo/Dx cell lines. The IC50 value for the LoVo/Dx cell line was higher, but still dose-dependent. Results from both assays demonstrated that p-aescin crystalline has the most cytotoxic activity toward human colon adenocarcinoma cell lines.

Non-invasive optical imaging of eosinophilia during the course of an experimental allergic airways disease model and in response to therapy.

BACKGROUND: Molecular imaging of lung diseases, including asthma, is limited and either invasive or non-specific. Central to the inflammatory process in asthma is the recruitment of eosinophils to the airways, which release proteases and proinflammatory factors and contribute to airway remodeling. The aim of this study was to establish a new approach to non-invasively assess lung eosinophilia during the course of experimental asthma by combining non-invasive near-infrared fluorescence (NIRF) imaging with the specific detection of Siglec-F, a lectin found predominantly on eosinophils. METHODOLOGY/PRINCIPAL FINDINGS: An ovalbumin (OVA)-based model was used to induce asthma-like experimental allergic airway disease (EAAD) in BALB/c mice. By means of a NIRF imager, we demonstrate that 48 h-72 h after intravenous (i.v.) application of a NIRF-labeled anti-Siglec-F antibody, mice with EAAD exhibited up to 2 times higher fluorescence intensities compared to lungs of control mice. Furthermore, average lung intensities of dexamethasone-treated as well as beta-escin-treated mice were 1.8 and 2 times lower than those of untreated, EAAD mice, respectively and correlated with the reduction of cell infiltration in the lung. Average fluorescence intensities measured in explanted lungs confirmed the in vivo findings of significantly higher values in inflamed lungs as compared to controls. Fluorescence microscopy of lung cryosections localized the i.v. applied NIRF-labeled anti-Siglec-F antibody predominantly to eosinophils in the peribronchial areas of EAAD lungs as opposed to control lungs. CONCLUSION/SIGNIFICANCE: We show that monitoring the occurrence of eosinophils, a prominent feature of allergic asthma, by means of a NIRF-labeled antibody directed against Siglec-F is a novel and powerful non-invasive optical imaging approach to assess EAAD and therapeutic response in mice over time.

ß-Escin inhibits NNK-induced lung adenocarcinoma and ALDH1A1 and RhoA/Rock expression in A/J mice and growth of H460 human lung cancer cells.

Lung cancer is the leading cause of cancer-related deaths. ß-Escin, a triterpene saponin isolated from horse chestnut seeds, was tested for inhibition of lung adenoma and adenocarcinoma induced by the tobacco carcinogen 4-(methyl-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in female A/J mice; and its possible mode of action was evaluated using the H460 human lung cancer cell line. At 6 weeks of age, 35 mice were fed AIN-76A-modified diet, and one week later, lung tumors were induced with a single intraperitoneal (i.p.) injection of 10 µmol NNK/mouse. Three weeks after the NNK treatment, groups of mice were fed either control or experimental diets containing 500 ppm for 20 weeks (10 control, 5 ß-escin) or 36 weeks (15 control, 5 ß-escin) and evaluated for lung tumor via histopathologic methods. Administration of 500 ppm ß-escin significantly suppressed lung tumor (adenoma + adenocarcinoma) formation by more than 40% (P < 0.0015) at 20 weeks and by 53.3% (P < 0.0001) at 37 weeks. ß-Escin inhibited NNK-induced lung adenocarcinoma formation by 65% (P < 0.001) at 20 weeks and by 53% (P < 0.0001) at 37 weeks. Immunohistochemical analysis revealed that lung tumors from mice exposed to ß-escin showed significantly reduced aldehyde dehydrogenase (ALDH)1A1 and phospho-Akt (p-Akt) expression when compared with those in mice fed control diet. Aldefluor assay for ALDH revealed that among H460 lung cancer cells treated with different concentrations of ß-escin (0-40 µmol/L), the subpopulation of cells with elevated ALDH activity was inhibited significantly. Our findings suggest that ß-escin inhibits tobacco carcinogen-induced lung tumor formation by modulating ALDH1A1-positive cells and RhoA/Rock signaling.

Apoptosis of human cholangiocarcinoma cell lines induced by ß-escin through mitochondrial caspase-dependent pathway.

The study aimed to evaluate the effects of ß-escin on human cholangiocarcinoma cell lines (QBC939, Sk-ChA-1 and MZ-ChA-1) and to explore its mechanisms. Cell growth, cell cycle and apoptosis were investigated, respectively, by MTT assay, single PI and FITC/PI double-staining flow cytometry, and fluorescence microscopy. The protein expression was determined by western blotting. The study revealed that ß-escin inhibited cholangiocarcinoma cell growth in a dose- and time-dependent manner, and the cell cycle of QBC939 and Sk-ChA-1 cells was arrested in the G2/M phase, and MZ-ChA-1 cells in G1 phase. Apoptosis of the three cholangiocarcinoma cell lines induced by ß-escin was associated with the collapse of the mitochondrial membrane potential and the activation of caspase-3. The apoptotic effect of ß-escin was suppressed by pancaspase inhibitor z-VAD-fmk. Molecular dissection revealed that the antiapoptotic protein bcl-2 was down-regulated after cholangiocarcinoma cell lines were treated with ß-escin, while the protein levels of bax and p53 were unchanged. Apoptosis was accompanied by an increase in reactive oxygen species (ROS). These results suggest that ß-escin induces apoptosis of cholangiocarcinoma cells through an intrinsic mitochondrial caspase-dependent pathway, and the increase in the bax/bcl-2 ratio and ROS may play important roles in ß-escin-induced apoptosis of cholangiocarcinoma cells.

Escin attenuates cerebral edema induced by acute omethoate poisoning.

Organophosphorus exposure affects different organs such as skeletal muscles, the gastrointestinal tract, liver, lung, and brain. The present experiment aimed to evaluate the effect of escin on cerebral edema induced by acute omethoate poisoning. Sprague-Dawley rats were administered subcutaneously with omethoate at a single dose of 60 mg/kg followed by escin treatment. The results showed that escin reduced the brain water content and the amount of Evans blue in omethoate-poisoned animals. Treatment with escin decreased the levels of tumor necrosis factor-alpha (TNF-α), matrix metalloproteinase-9 (MMP-9), cyclooxygenase-2 (COX-2), and prostaglandin E2 (PGE2) in the brain. Escin also alleviated the histopathological change induced by acute omethoate poisoning. The findings demonstrated that escin can attenuate cerebral edema induced by acute omethoate poisoning, and the underlying mechanism was associated with ameliorating the permeability of the blood-brain barrier.