Protective effects of paeoniflorin against cobalt chloride-induced apoptosis of endothelial cells via HIF-1α pathway

Paeoniflorin attenuates polystyrene nanoparticle-induced reduction in reproductive capacity and increase in germline apoptosis through suppressing DNA damage checkpoints in Caenorhabditis elegans

Due to high sensitivity to environmental exposures, Caenorhabditis elegans is helpful for toxicity evaluation and toxicological study of pollutants. Using this animal model, we investigated the reproductive toxicity of 20 nm polystyrene nanoparticle (PS-NP) in the range of μg/L and the following pharmacological intervention of paeoniflorin. After exposure from L1-larvae to young adults, 10-100 μg/L PS-NP could cause the reduction in reproductive capacity reflected by the endpoints of brood size and number of fertilized eggs in uterus. Meanwhile, the enhancements in germline apoptosis analyzed by AO staining and germline DNA damage as shown by alteration in HUS-1::GFP signals were detected in 10-100 μg/L PS-NP exposed nematodes, suggesting the role of DNA damage-induced germline apoptosis in mediating PS-NP toxicity on reproductive capacity. Following the exposure to 100 μg/L PS-NP, posttreatment with 25-100 mg/L paeoniflorin increased the reproductive capacity and inhibited both germline apoptosis and DNA damage. In addition, in 100 μg/L PS-NP exposed nematodes, treatment with 100 mg/L paeoniflorin modulated the expressions of genes governing germline apoptosis as indicated by the decrease in ced-3, ced-4, an egl-1 expressions and the increase in ced-9 expression. After exposure to 100 μg/L PS-NP, treatment with 100 mg/L paeoniflorin also decreased expressions of genes (cep-1, clk-2, hus-1, and mrt-2) governing germline DNA damage. Molecular docking analysis further demonstrated the binding potential of paeoniflorin with three DNA damage checkpoints (CLK-2, HUS-1, and MRT-2). Therefore, our data suggested the toxicity of PS-NP in the range of μg/L on reproductive capacity after exposure from L1-larvae to young adults, which was associated with the enhancement in DNA damage-induced germline apoptosis. More importantly, the PS-NP-induced reproductive toxicity on nematodes could be inhibited by the following paeoniflorin treatment.

Therapeutic potential of paeoniflorin in atherosclerosis: A cellular action and mechanism-based perspective

Epidemiological studies have shown that the incidence, prevalence and mortality of atherosclerotic cardiovascular disease (ASCVD) are increasing globally. Atherosclerosis is characterized as a chronic inflammatory disease which involves inflammation and immune dysfunction. P. lactiflora Pall. is a plant origin traditional medicine that has been widely used for the treatment of various diseases for more than a millennium in China, Japan and Korean. Paeoniflorin is a bioactive monomer extracted from P. lactiflora Pall. with anti-atherosclerosis effects. In this article, we comprehensively reviewed the potential therapeutic effects and molecular mechanism whereby paeoniflorin protects against atherosclerosis from the unique angle of inflammation and immune-related pathway dysfunction in vascular endothelial cells, smooth muscle cells, monocytes, macrophages, platelets and mast cells. Paeoniflorin, with multiple protective effects in atherosclerosis, has the potential to be used as a promising therapeutic agent for the treatment of atherosclerosis and its complications. We conclude with a detailed discussion of the challenges and future perspective of paeoniflorin in translational cardiovascular medicine.

Soy Isoflavones Protect Neuronal PC12 Cells against Hypoxic Damage through Nrf2 Activation and Suppression of p38 MAPK and AKT-mTOR Pathways

Isoflavones are a class of major phenolic compounds, derived from soybeans, that possess unique therapeutic and biological properties. The possible mechanisms of isoflavone-mediated protection of neuronal PC12 cells against hypoxic damage was investigated in this study. Isoflavones showed potential neuroprotective effects by increasing cell viability, decreasing the level of reactive oxygen species (ROS), and inhibiting apoptosis and cell cycle arrest in cobalt chloride (CoCl₂)-induced hypoxic damage. A Western blot analysis indicated that isoflavones decreased apoptosis by up-regulating the Bcl-xL protein and down-regulating the Bax protein. They further reduced the S-phase fraction of the cell cycle by down-regulating the p21 protein and up-regulating the cyclin A protein levels. Additionally, isoflavones activated Nrf2 protein translocation and inhibited the p38 MAPK and AKT–mTOR pathways. A molecular docking analysis further revealed that isoflavones displayed a potential competitive interaction with the Nrf2 protein for Keap1. Our findings suggest that isoflavones could be a potent neuroprotective phytochemical in soybeans and their products.

Paeoniflorin alleviates endothelial dysfunction caused by overexpression of soluble fms-like tyrosine kinase 1 and soluble endoglin in preeclampsia via VEGFA upregulation

This study assessed the protective effects of paeoniflorin against preeclampsia-related endothelial damage (ED). Human umbilical vein endothelial cells (HUVECs) isolated from healthy puerperae were identified by immunofluorescence assay. After paeoniflorin treatment, HUVECs were induced by soluble fms-like tyrosine kinase 1 (sFlt-1) and soluble endoglin (sEng) to establish ED. Cell viability, migration, invasion, tube formation, and apoptosis were assessed by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) tetrazolium MTT assay, Scratch assay, Transwell assay, tube formation assay, and flow cytometry. VEGFA expression in HUVECs was analyzed by Western blot. HUVECs were successfully isolated and identified as Von Willebrand factor (vWF) positive. Individual treatment or cotreatment of sFlt-1 and sEng inhibited migration, invasion and tube formation, enhanced apoptosis, and decreased VEGFA expression in HUVECs. Paeoniflorin pretreatment partially reversed the effects delivered by cotreatment of sFlt-1 and sEng in HUVECs. Paeoniflorin alleviated preeclampsia-related ED caused by overexpression of sFlt-1 and sEng by upregulating VEGFA.

Anti-inflammatory effects of paeoniflorin caused by regulation of the hif1a/miR-210/caspase1/GSDMD signaling pathway in astrocytes: a novel strategy for hypoxia-induced brain injury in rats

Context: Hypoxia-induced injury is a classic symptom of obstructive sleep apnea hypopnea syndrome (OSAHS), which is a risk factor of various diseases, such as hypertension, heart failure and stroke. However, there is no effective therapy for hypoxia-induced injury or OSAHS due to the elusive mechanism involved.Objective: This study aimed to assess the effects of paeoniflorin on hypoxia-induced injury and explore the underlying mechanism.Materials and methods: Hypoxic models of SD rats and CTX-TNA2 cells were used to assess the effect of paeoniflorin, and the expressions of hif1a, miR-210, caspase1 and GSDMD were detected using western blots and RT-PCR. Plasmid transfection was performed to explore the role of miR-210 in the effect of paeoniflorin.Results: Firstly, we confirmed that hypoxia induced severe neuronal injury and an enhancement of inflammation in the rat brain, with elevated expression of caspase1, IL1b and IL18. In addition, the results showed an activation of astrocytes and an increased level of pyroptosis under hypoxic conditions, which suggested a critical role of pyroptosis in hypoxiainduced injury of the brain. Furthermore, we found that compared with the controls, paeoniflorin treatment improved hypoxia-induced pyroptosis in astrocytes. Moreover, we detected the activation of hif1a/miR-210 signaling in the effects of paeoniflorin on astrocytes. As expected, the expression of hif1a and miR-210 was significantly upregulated in astrocytes when exposed to hypoxia, while paeoniflorin treatment reversed these enhancements. After transfection of miR-210 mimics, the attenuation of pyroptosis induced by paeoniflorin was suppressed, which was accompanied by an increase of ROS levels, as well as LDH release, indicating a critical role of miR-210 in pyroptosis in astrocytes.Conclusions: Our findings demonstrated that paeoniflorin improved hypoxia-induced pyroptosis in astrocytes via depressing hif1a/miR-210/caspase1/GSDMD signaling, providing robust evidence for the treatment of hypoxic injury and OSAHS.HighlightsHypoxia induces severe injury and inflammatory response in the rat brain;Hypoxia enhanced pyroptotic level and led to an activation of astrocytes.;Paeoniflorin alleviates hypoxia-induced pyroptosis in astrocytes;Transfection of miR-210 mimics suppressed the effects of paeoniflorin on hypoxia-induced pyroptosis in astrocytes.

Angiogenic Actions of Paeoniflorin on Endothelial Progenitor Cells and in Ischemic Stroke Rat Model

Ischemic stroke is one of the major diseases with high morbidity, mortality, and disability rate all over the world. Chinese herb-derived active components would provide valuable candidate compounds for ischemic stroke therapy. Paeoniflorin (PF) is an active ingredient from Paeoniae Radix which possesses neurovascular effect after ischemia. However, so far, few studies are reported on the efficacy and mechanism of PF from angiogenesis aspects. Results from our in vitro studies showed that the ability for proliferation, migration, and tube formation in bone marrow-derived endothelial progenitor cells (BM-EPCs) was promoted by coculturing with PF (100 [Formula: see text]M). Furthermore, to investigate the angiogenic effects of PF in vivo, we constructed an ischemic stroke model in rats and found that PF could reduce cerebral infarction, alleviate pathological injury, and increase the secretion of pro-angiogenic factors and cerebral vascular density after intraperitonially administration of 40 mg ⋅ kg[Formula: see text] ⋅ day[Formula: see text] for 14 days. Up-regulating the expression of VEGF/VEGF-R₂ might be the mechanism of PF's angiogenic action. In conclusion, the present study provides evidence that PF is an active monomer of Traditional Chinese Medicine which shows angiogenic actions on endothelial progenitor cells and in ischemic stroke rat model.

Effects of Chaihu-Shugan-San on Small Intestinal Interstitial Cells of Cajal in Mice

Chaihu-Shugan-San (CSS) has been widely used as an alternative treatment for gastrointestinal (GI) diseases in East Asia. Interstitial cells of Cajal (ICCs) are pacemakers in the GI tract. In the present study, we examined the action of CSS on pacemaker potentials in cultured ICCs from the mouse small intestine in vitro and on GI motility in vivo. We used the electrophysiological methods to measure the pacemaker potentials in ICCs. GI motility was investigated by measuring intestinal transit rates (ITR). CSS inhibited the pacemaker potentials in a dose-dependent manner. The capsazepine did not block the effect of CSS. However, the effects of CSS were blocked by glibenclamide. In addition, N^G-nitro-L-arginine methyl ester (L-NAME) also blocked the CSS-induced effects. Pretreatment with SQ-22536 or with KT-5720 did not suppress the effects of CSS; however, pretreatment with ODQ or KT-5823 did. Furthermore, CSS significantly suppressed murine ITR enhancement by neostigmine in vivo. These results suggest that CSS exerts inhibitory effects on the pacemaker potentials of ICCs via nitric oxide (NO)/cGMP and ATP-sensitive K⁺ channel dependent and transient receptor potential vanilloid 1 (TRPV1) channel independent pathways. Accordingly, CSS could provide the basis for the development of new treatments for GI motility dysfunction.

Paeoniflorin Ameliorates Chronic Hypoxia/SU5416-Induced Pulmonary Arterial Hypertension by Inhibiting Endothelial-to-Mesenchymal Transition

Background

Endothelial cells dysfunction is one of the hallmark pathogenic features of pulmonary arterial hypertension (PAH). Paeoniflorin (PF) is a monoterpene glycoside with endothelial protection, vasodilation, antifibrotic, anti–inflammatory and antioxidative properties. However, the effects of PF on PAH remain unknown.

Methods

Here, we investigated the efficacy of PF in the SU5416/hypoxia (SuHx) rat model of PAH. Human pulmonary arterial endothelial cells (HPAECs) were exposed to 1% O₂ with or without PF treatment.

Results

Hemodynamics analysis showed that prophylactic treatment with PF (300 mg/kg i.g. daily for 21 days) significantly inhibited chronic hypoxia/SU5416-induced elevations of right ventricular systolic pressure (RVSP) and right ventricular hypertrophy index in rats. Meanwhile, PF significantly reduced pulmonary vascular remodeling, as well as alleviated collagen deposition in lungs and right ventricles in SuHx rats. Additionally, PF inhibited SuHx–induced down-regulation of endothelial marker (vascular endothelial cadherin) and up-regulation of mesenchymal markers (fibronectin and vimentin) in lung, suggesting that PF could inhibit SuHx–induced endothelial-to-mesenchymal transition (EndMT) in lung. Further in vitro studies confirmed that PF treatment suppressed hypoxia-induced EndMT in HPAECs, which was abolished by the knockdown of bone morphogenetic protein receptor type 2 (BMPR2) in HPAECs.

Conclusion

Taken together, our findings suggest that PF ameliorates BMPR2 down-regulation-mediated EndMT and thereafter alleviates SuHx–induced PAH in rats.

Dietary cobalt supplementation improves growth and body composition and induces the expression of growth and stress response genes in Tor putitora

A 90-day randomized feeding experiment was performed to assess the effects of dietary cobalt (Co) supplementation on the growth performance, muscle composition, status of iron and manganese in the muscle as well as the expression of growth-related genes in the muscle (myoblast determination protein 1 homolog (MyoD) and myogenin) and the stress-related gene heat shock protein 70 KDa (Hsp-70) in the liver of mahseer (Tor putitora). Feeding trial was conducted in triplicate under controlled semi-static conditions, and graded levels of dietary cobalt (0.5-3 mg/kg) were fed to six groups of advanced fry of T. putitora. The results obtained indicated a curvilinear relationship of dietary Co levels with body crude protein content and weight gain (%). A positive correlation was observed with up to 2 mg Co/kg diet. However, a decreasing trend was found with values over 2 mg Co/kg diet. The expression of muscle growth biomarkers MyoD and myogenin showed a similar response, upregulation up to 2 mg Co/kg diet and decreased expression at 3 mg Co/kg diet. Indeed, the highest dietary Co supplementation increased the expression of Hsp-70, a key gene expressed in response to stress. Moreover, the muscle content of iron and manganese showed an inverse relationship with the dietary Co supplementation. Our findings suggest that 2 mg/kg Co dietary supplementation stimulates myogenesis and optimize muscle growth and body composition, while higher levels enhanced the expression of stress response genes and impaired growth of T. putitora.

Anti-inflammatory and immunoregulatory effects of paeoniflorin and total glucosides of paeony

As a Traditional Chinese Medicine, Paeonia lactiflora Pallas has been used to treat pain, inflammation and immune disorders for more than 1000 years in China. Total glycoside of paeony (TGP) is extracted from the dried root of Paeonia lactiflora Pallas. Paeoniflorin (Pae) is the major active component of TGP. Our research group has done a lot of work in the pharmacological mechanisms of Pae and found that Pae possessed extensive anti-inflammatory and immune regulatory effects. Pae could inhibit inflammation in the animal models of autoimmune diseases, such as experimental arthritis, psoriatic mice and experimental autoimmune encephalomyelitis, and so on. Pae modulates the functions and activation of immune cells, decreases inflammatory medium production, and restores abnormal signal pathway. Pae could balance the subsets of immune cells through inhibiting abnormal activated cell subsets and restoring regulatory cell subsets. Pae could regulate signaling pathways (GPCR pathway, MAPKs /NF-κB patway, PI3K /Akt /mTOR pathway, JAK2 /STAT3 pathway, TGFβ /Smads, and etc.). TGP is composed of Pae, hydroxyl-paeoniflorin, paeonin, albiflorin and benzoylpaeoniflorin etc. Pae accounts for more than 40% of TGP. Like Pae, TGP has anti-inflammatory and immune regulatory effects. TGP has been widely used to treat autoimmune diseases, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), psoriasis, allergic contact dermatitis, and etc. in China. Furthermore, TGP has some superior features with immune regulation, gentle effect, many indications and few adverse drug reactions. These findings suggest that TGP may be a promising anti-inflammatory and immune drug with soft regulation and has more superiority in the treatment of AIDs. Currently, TGP is used for the treatment of RA, SLE and other AIDs in more than 1000 hospitals in China, which obtained great social and economic benefits.

Nuclear GAPDH is vital for hypoxia-induced hepatic stellate cell apoptosis and is indicative of aggressive hepatocellular carcinoma behavior

Background/aim: Hepatic stellate cells (HSCs) are critical determinants of liver tumor behavior such as vascular invasion, cell proliferation and migration. The apoptosis of HSCs can inhibit tumor growth and contribute to repressing hepatocellular carcinoma (HCC) progression. Our study aims to investigate the impact of nuclear glyceraldehyde-3-phosphate dehydrogenase (GAPDH) on HSCs under hypoxic conditions and the association of nuclear GAPDH with HCC patient outcomes and tumor progression.

Patients and methods: Following stable cell passage, 0.3% O₂ was used to induce hypoxia. Cell proliferation and apoptosis were analyzed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assays and flow cytometry, respectively. Proteins expression were detected by extracting nuclear and cytoplasmic proteins and performing Western blots. GAPDH nuclear translocation was blocked by the agent deprenyl. Immunohistochemical staining for GAPDH was investigated in 137 HCC tissue samples from our center. An analysis of the clinicopathological features, Kaplan-Meier analysis and Cox proportional hazards regression analysis were applied.

Results: MTT assays and flow cytometry analyses showed that the nuclear accumulation of GAPDH led to the apoptotic death of HSCs, while blockade of this process with deprenyl significantly decreased apoptosis. Western blots revealed that deprenyl inhibited the nuclear translocation of GAPDH. An analysis of the immunohistochemical staining of HSCs in HCC tissue samples (137) revealed that nuclear GAPDH expression was significantly positively correlated with HIF-1α expression. Overall survival (OS) and time-to-recurrence (TTR) estimated by Kaplan-Meier analyses showed that patients with high HIF-1α or low nuclear GAPDH levels in HSCs had significantly poorer prognosis compared with patients with low HIF-1α or high nuclear GAPDH expression in HSCs. Moreover, patients with combined high HIF-1α/low nuclear GAPDH expression in HSCs had the worst prognosis. The Cox regression analysis revealed that the combination of nuclear GAPDH/HIF-1α expression in HSCs was an independent prognostic factor for OS and TTR in HCC patients.

Conclusions: These findings provide a novel mechanism underlying the involvement of intranuclear GAPDH in hypoxia-induced HSCs apoptosis and a correlation between nuclear GAPDH levels and the clinical prognosis, which may prompt the development of a novel therapeutic strategy for HCC.

Diversity of endophytic fungi of Paeonia lactiflora Pallas and screening for fungal paeoniflorin producers

Endophytic fungi from Paeonia lactiflora Pallas, which is mainly distributed in China, were characterized and screened to identify those capable of producing paeoniflorin. A total of 101 isolates obtained from the roots, stems and leaves of P. lactiflora were grouped into 16 fungal taxa based on morphological traits and internal transcribed spacers sequences, indicating that endophytic fungi of P. lactiflora are abundant and diverse. The dominant endophytic fungi were Aspergillus, Alternaria and Penicillium. More fungi were recovered from leaves than from roots and stems. The similarity index was highest between the stems and leaves (0.733), followed by the roots and leaves (0.615) and the stems and roots (0.563). Analyses of the fermentation extracts of 22 endophytic fungi by high-performance liquid chromatography and mass spectrometry revealed that three strains (R12, Alternaria tenuissima; S4, Aspergillus flavus; and R17 Penicillium commune) were able to produce paeoniflorin. Among the paeoniflorin-producing fungi, the yield of paeoniflorin from A. flavus S4 was 342.4 μg/L, and this strain could be used as a candidate for the industrial production of paeoniflorin.

Paeoniflorin improves cardiac function and decreases adverse postinfarction left ventricular remodeling in a rat model of acute myocardial infarction

Background

Paeoniflorin (PF) is the active component of Paeonia lactiflora Pall. or Paeonia veitchii Lynch. This study was, therefore, aimed to evaluate the improvement and mechanism of the PF on ventricular remodeling in rats with acute myocardial infarction (AMI).

Materials and methods

In this study, AMI model was established by ligating the anterior descending coronary artery in Wistar rats. After 4 weeks gavage of PF, the apparent signs and the left ventricle weight index of Wistar rats were observed. The left ventricular ejection fraction (LVEF) was evaluated by Doppler ultrasonography. Changes in cardiac morphology were observed by pathologic examination, and apoptosis was observed by the terminal deoxynucleotidyl transferase dUTP nick end labeling assay. In addition, enzyme-linked immunosorbent assay was used to detect the expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) interleukin-10 (IL-10) and brain natriuretic peptide (BNP). Immunohistochemistry and Western blot method were applied to detect Caspase-3 and Caspase-9.

Results

Compared with the model control, the survival conditions of rats in all treatment groups were generally improved after PF treatment. LVEF was significantly increased, and both left ventricular end-diastolic inner diameter and left ventricular end-systolic inner diameter were significantly reduced. Moreover, pathologic examination showed that the myocardium degeneration of the rats treated with PF was decreased, including neater arrangement, more complete myofilament, more uniform gap and less interstitial collagen fibers. Furthermore, the mitochondrial structure of cardiomyocytes was significantly improved. The ultrastructure was clear, and the arrangement of myofilament was more regular. Also, the expression of Caspase-3 and Caspase-9 was inhibited, and apoptosis was obviously reduced in the PF treatment groups. BNP, TNF-α and IL-6 were also decreased and IL-10 was increased in the treated rats.

Conclusion

PF could significantly improve the LVEF of rats. It decreased adverse left ventricular remodeling after myocardial infarction in rat models. The potential mechanism could be that PF decreased and inhibited BNP, TNF-α and IL-6, increased IL-10 and further inhibited the expression of Caspase-3 and Caspase-9, thus promoting ventricular remodeling.

Paeoniflorin inhibits VSMCs proliferation and migration by arresting cell cycle and activating HO-1 through MAPKs and NF-κB pathway

The proliferation, migration and inflammation of vascular smooth muscle cells (VSMCs) contributes to the pathogenesis and progression of atherosclerosis. Paeoniflorin (PF) as active compound in the Rhizoma Atractylodes macrocephala has been used for various diseases like cancer, splenic asthenia, anaphylaxis and anorexia. This study aimed to explore whether and how PF regulated the inflammation, proliferation and migration of VSMCs under ox-LDL stimulation. Here, we found that PF dose-dependently inhibited ox-LDL-induced VSMCs proliferation and migration, and decreased inflammatory cytokines and chemokine overexpression. Mechanistically, PF prevented p38, ERK1/2 and NF-κB phosphorylation, and arrested cell cycle in S phase. Meanwhile, PF regulated the HO-1 and PCNA expression. Furthermore, PF blocked the foam cell formation in macrophages induced by ox-LDL. These results indicate that PF antagonizes the ox-LDL-induced VSMCs proliferation, migration and inflammation through activation of HO-1, cell cycle arrest and then suppression of p38, ERK1/2/MAPK and NF-κB signaling pathways.

Liuwei Dihuang soft capsules attenuates endothelial cell apoptosis to prevent atherosclerosis through GPR30-mediated regulation in ovariectomized ApoE-deficient mice

ETHNOPHARMACOLOGICAL RELEVANCE

Liuwei Dihuang (LWDH), a classical traditional Chinese medicine prescription, has been widely used to prevent and to treat various diseases with symptoms of 'Kidney-Yin' deficiency syndrome for over 1000 years in China. It is commonly used to treat functional decline associated with senile disease and menopausal syndrome, especially memory decline, insomnia, diabetes and osteoporosis. Modern experimental pharmacological studies indicated that the mechanism of LWDH treatment of menopausal syndrome may be associated with enhanced estrogenic effects. However, little attention has been paid to the potential impact of LWDH on atherosclerosis (AS) associated with female menopause. The aim of this study was to evaluate the preventive effects of LWDH intake on an animal model of female menopause AS and to explore the underlying molecular mechanism.

MATERIALS AND METHODS

ApoE^-/- mice were randomly divided into 4 groups, with C57BN/L6 mice as the control group. All ApoE^-/- mice were ovariectomized (Ovx) one week prior to oral administration and initiation of high-fat diet. C57BL/6 mice were given sham operation and maintained on normal diet. The three administered groups were given simvastatin (4mg/kg via i.g.) and LWDH (4.5, 9.0g/kg via i.g.) every day for 14 weeks. Atherosclerotic lesions in the aortic root were determined by oil red O staining and hematoxylin-eosin staining. α-Actin and CD68 in atherosclerotic lesions were detected by immunohistological assay. Serum lipids and homocysteine (Hcy) levels were measured in the 14th week. The cleaved caspase-3, C/EBP homologous protein (CHOP) and G protein coupled estrogen receptor 30 (GPR30) expressions in the aortic arch endothelium were determined by immunohistochemistry and Western blot. The inhibitory effect of LWDH-medicated (20%, 12h) on Hcy (20%, 24h)-induced apoptosis of human umbilical vein endothelial cells (HUVECs) was examined by flow cytometry and Hoechst 33258 staining. Intracellular ROS production, nitric oxide release, and endothelial NO synthase (eNOS) activity were measured with or without LWDH-medicated serum pretreatment. In addition, CHOP, glucose-regulated protein GPR30, 78 (Grp78), Bcl-2, Bax and cleaved caspase-3 were analyzed by Western blot. Finally, the influence of G15, a specific antagonist of GPR30, on the protective effect of LWDH on endothelial cells was investigated.

RESULTS

In vivo administration of LWDH prevented plaque formation and reduced plasma lipid and Hcy levels. LWDH inhibited CHOP and cleaved caspase-3 expression in vivo and in vitro while maintaining GPR30 expression. In vitro study showed that Hcy-induced HUVECs apoptosis was weakened by LWDH-medicated serum pretreatment. Treatment with LWDH-medicated serum significantly upregulated NO release and eNOS activity in HUVECs. In addition, LWDH-medicated serum treatment optimized the balance between Bax and Bcl-2, and attenuated intracellular ROS production. G15 reversed the protective effect of LWDH on endothelial cells and the changes of apoptosis-related proteins.

CONCLUSIONS

LWDH treatment can significantly reduce plaque formation in an animal model of menopausal AS. The mechanism may be inhibition of Hcy-induced endothelial cell apoptosis by modulating GPR30. Hence, LWDH can potentially be used to prevent AS-related vascular disease in menopausal women.

Toxicity and Apoptosis Related Effects of Benzimidazo [3,2-α] Quinolinium Salts Upon Human Lymphoma Cells

OBJECTIVES

The present study evaluates novel cationic quinoline derivatives known as benzimidazo[3,2-a]quinolinium salts (BQS) named NBQ-48 and ABQ-48 that have structural similarities to known anti-cancer substances such as ellipticine and berberine.

METHODS

Toledo human lymphoma (ATCC CRL2631) cells were treated for 24 to 48 hours. Apoptosis related endpoints such as cell cycle arrest, mitochondrial damage, RNS and ROS generation and the activity of several apoptosis related proteins such as caspases and apoptosis inducing factor (AIF) were studied using fluorescence staining and western blot respectively.

RESULTS

Results indicated a higher toxicity from the amino substituted ABQ-48 versus the NBQ-48 (GI50's of 50uM versus 100uM respectively). Both compounds induced cell death through various apoptosis related endpoints including a decrease in mitochondrial membrane potential with an increase in ROS and activation of the effector caspase 3. Interestingly, AIF release was observed on cells treated with the amino substituted ABQ-48 but not on the nitro substituted NBQ-48 samples suggesting a caspase independent mechanism for ABQ-48.

CONCLUSIONS

The results obtained presents the toxic effects of two novel benzimidazo[3,2-a]quinolinium salts in human lymphoma tumor cells. The identified mechanism of action includes multiple apoptosis related effects. Furthermore the data presents a clear variation in caspase dependent or independent mechanism for each compound.

Enhancement of Exposure and Reduction of Elimination for Paeoniflorin or Albiflorin via Co-Administration with Total Peony Glucosides and Hypoxic Pharmacokinetics Comparison

There is evidence suggesting that herbal extracts demonstrate greater bioactivities than their isolated constituents at an equivalent dose. This phenomenon could be attributed to the absence of interacting substances present in the extracts. By measuring the pharmacokinetic parameters of paeoniflorin (PF) and albiflorin (AF) after being orally administered to rats in isolated form, in combination with each other and within total peony glucosides (TPG), respectively, the current study aimed to identify positive pharmacokinetic interactions between components of peony radix extracts. Moreover, the pharmacokinetic profiles of PF and AF under normoxia and hypoxia were also investigated and compared. In order to achieve these goals, a highly sensitive and reproducible ultra-peformance liquid chromatography-mass spectrometry (UPLC-MS) method was developed and validated for simultaneously quantitation of PF and AF in rat plasma. This study found that compared with that of single component (PF/AF), the exposure of PF in rat plasma after combination administration or TPG administration was significantly increased, meanwhile the elimination of PF/AF was remarkably reduced. It was also noticed that AUC and Cmax of PF in hypoxia rats were significantly decreased compared with that of normaxia rats, suggesting that there was a decreased exposure of PF in rats under hypoxia. The current study, for the first time, revealed the pharmacokinetic interactions between PF/AF and other constitutes in TGP and the pharmacokinetic profiles of PF and AF under hypoxia. In view of the current findings, it could be supposed that the clinical performance of total peony glucosides would be better than that of single constitute (PF/AF). The outcomes of this animal study are expected to serve as a basis for development of clinical guidelines on total peony glucosides usage.

Elucidation of Transport Mechanism of Paeoniflorin and the Influence of Ligustilide, Senkyunolide I and Senkyunolide A on Paeoniflorin Transport through Mdck-Mdr1 Cells as Blood-Brain Barrier in Vitro Model

The objectives of the present investigation were to: (1) elucidate the transport mechanism of paeoniflorin (PF) across MDCK-MDR1 monolayers; and (2) evaluate the effect of ligustilide (LIG), senkyunolide I (SENI) and senkyunolide A (SENA) on the transport of PF through blood–brain barrier so as to explore the enhancement mechanism. Transport studies of PF were performed in both directions, from apical to basolateral side (A→B) and from basolateral to apical sides (B→A). Drug concentrations were analyzed by LC-MS/MS. PF showed relatively poor absorption in MDCK-MDR1 cells, apparent permeability coefficients (Papp) ranging from 0.587 × 10⁻⁶ to 0.705 × 10⁻⁶ cm/s. In vitro experiments showed that the transport of PF in both directions was concentration dependent and not saturable. The B→A/A→B permeability ER of PF was more than 2 in the MDCK-MDR1 cells, which indicated that the transport mechanism of PF might be passive diffusion as the dominating process with the active transportation mediated mechanism involved. The increased Papp of PF in A→B direction by EDTA-Na₂ suggested that PF was absorbed via the paracellular route. The P-gp inhibitor verapamil could significantly increase the transport of PF in A→B direction, and ER decreased from 2.210 to 0.690, which indicated that PF was P-gp substance. The transport of PF in A→B direction significantly increased when co-administrated with increasing concentrations of LIG, SENI and SENA. An increased cellular accumulation of Rho 123 and Western blot analysis indicated that LIG, SENI and SENA had increased the transport of PF in the BBB models attribute to down-regulate P-gp expression. A decrease in transepithelial electrical resistance (TEER) during the permeation experiment can be explained by the modulation and opening of the tight junctions caused by the permeation enhancer LIG, SENI and SENA.

Danggui-Shaoyao-San: New Hope for Alzheimer's Disease

Danggui-Shaoyao-San (DSS), also called Toki-shakuyaku-san (TJ-23) or Dangguijakyak-san (DJS), is a well-known herbal formula (Angelica sinensis (Oliv.) Diels., Ligusticum chuanxiong Hort., Paeonia lactiflora pall., Poria cocos (Schw.) Wolf, Alisma orientalis (Sam.) Juzep., Atractylodes macrocephala Koidz.), which has been widely used in oriental countries for the treatment of various gynecological diseases. Recent studies show that DSS has an effect on free radical-mediated neurological diseases and exhibits anti-inflammatory and antioxidant activities and reduces cell apoptosis in the hippocampus. In addition, DSS mediates the modulation of central monoamine neurotransmitter systems and ameliorates dysfunction of the central cholinergic nervous system and scopolamine-induced decrease in ACh levels. DSS improves the function of the dopaminergic, adrenergic, and serotonergic nervous systems. Interestingly, DSS can alleviate cognitive dysfunction of Alzheimer's disease (AD) patients, suggesting that it is a useful therapeutic agent for AD. This paper reviews the mechanism of DSS for the treatment of AD.

Bazhen decoction protects against acetaminophen induced acute liver injury by inhibiting oxidative stress, inflammation and apoptosis in mice

Bazhen decoction is a widely used traditional Chinese medicinal decoction, but the scientific validation of its therapeutic potential is lacking. The objective of this study was to investigate corresponding anti-oxidative, anti-inflammatory and anti-apoptosis activities of Bazhen decoction, using acetaminophen-treated mice as a model system. A total of 48 mice were divided into four groups. Group I, negative control, treated with vehicle only. Group II, fed with 500 mg/kg/day Bazhen decoction for 10 continuous days. Group III, received a single dose of 900 mg/kg acetaminophen. Group IV, fed with 500 mg/kg/day Bazhen decoction for 10 continuous days and a single dose of 900 mg/kg acetaminophen 30 min before last Bazhen decoction administration. Bazhen decoction administration significantly decrease acetaminophen-induced serum ALT, AST, ALP, LDH, TNF-α, IL-1β, ROS, TBARS and protein carbonyl group levels, as well as GSH depletion and loss of MMP. Bazhen decoction restore SOD, CAT, GR and GPx activities and depress the expression of pro-inflammatory factors, such as iNOS, COX-2, TNF-α, NF-κB, IL-1β and IL-6, respectively. Moreover, Bazhen decoction down-regulate acetaminophen-induced Bax/Bcl-2 ratio, caspase 3, caspase 8 and caspase 9. These results suggest the anti-oxidative, anti-inflammatory and anti-apoptosis properties of Bazhen decoction towards acetaminophen-induced liver injury in mice.

Toxic effects of xylazine on endothelial cells in combination with cocaine and 6-monoacetylmorphine

The use of xylazine as a drug of abuse has emerged worldwide in the last 7 years, including Puerto Rico. Clinical findings reported that xylazine users present greater physiological deterioration, than heroin users. The aim of this study was to assess the xylazine toxicity on endothelial cells, as this is one of the first tissues impact upon administration. Human umbilical vein endothelial cells in culture were treated with xylazine, cocaine, 6-monoacetylmorphine (heroin metabolite) and its combinations, at concentrations of 0.10-400 μM, for periods of 24, 48 and 72 h. IC50 were calculated and the Annexin V assay implemented to determine the cell death mechanism. Results indicated IC50 values at 24h as follow: xylazine 62 μM, cocaine 210 μM, 6-monoacetylmorphine 300 μM. When these drugs were combined the IC50 value was 57 μM. Annexin V results indicated cell death by an apoptosis mechanism in cells treated with xylazine or in combination. Results demonstrated that xylazine use inhibits the endothelial cell proliferation, at lower concentrations than cocaine and 6-monoacetylmorphine. These findings contribute to the understanding of the toxicity mechanisms induced by xylazine on endothelial cells.

Cyanidin-3-O-glucoside modulates intracellular redox status and prevents HIF-1 stabilization in endothelial cells in vitro exposed to chronic hypoxia

The term hypoxia refers to conditions characterized by a relative restriction of oxygen supply. It is usually associated to a paradoxical overproduction of reactive oxygen species (ROS) and to the activation of several transcription factors, including HIF-1α, which in turn trigger angiogenic and apoptotic response. In this study we have investigated the mechanisms by which the anthocyanin cyanidin-3-O-glucoside (C3G) modulates hypoxia induced response in human endothelial cells (HUVECs). In fact, hypoxia induces an increase of ROS generation in HUVECs paralleled by a loss of antioxidant cellular capacity. According to the observed increase of HO-1 mRNA expression, pretreatment of C3G to HUVEC reduces the entity of oxidative stress thanks to the activation of cellular antioxidant response. C3G also attenuates HIF-1α protein accumulation conditions supporting the hypothesis of a major role of oxidative stress in the presence of low oxygen. Furthermore, the increased expression of angiogenesis and apoptosis markers (MMP-2 and caspase-3) due to HIF-1α activation by hypoxia is reduced in C3G pretreated cells. Overall, our data suggest that the modulation of intracellular redox status induced by C3G may be an important protective mechanism against endothelial damage in hypoxic conditions.

SIRT1 inhibits TNF-α-induced apoptosis of vascular adventitial fibroblasts partly through the deacetylation of FoxO1

Sirtuin 1 (SIRT1), a NAD(+)-dependent class III histone deacetylase, participates in regulating cellular apoptosis, senescence and metabolism by deacetylating histones and multiple transcription factors. In this study, we aimed to determine the effect of SIRT1 on the apoptosis of vascular adventitial fibroblasts (VAFs) and related signaling pathways. SIRT1 was found in the nucleus of VAFs and translocated into the cytoplasm in response to tumor necrosis factor-α (TNF-α). Moreover, SIRT1 protein expression was reduced in VAFs stimulated with TNF-α. In addition, TNF-α increased the apoptosis of VAFs. Activation of SIRT1 by resveratrol (RSV) or overexpression of SIRT1 attenuated TNF-α-induced VAF apoptosis by decreasing the percentage of apoptotic cells and cleaved caspase-3 protein expression and increasing the Bcl-2/Bax ratio. In contrast, inhibition of SIRT1 by sirtinol/nicotinamide or knockdown of SIRT1 enhanced apoptosis of VAFs. On the other hand, knockdown of FoxO1 reduced TNF-α-induced VAF apoptosis. SIRT1 interacted with FoxO1 in VAFs by the co-immunoprecipitation assay. Further study showed that RSV or SIRT1 overexpression decreased acetylated-FoxO1 (Ac-FoxO1) protein expression in VAFs stimulated with TNF-α. Knockdown of SIRT1 resulted in an increase in Ac-FoxO1 protein expression. Taken together, these findings indicate that SIRT1 inhibits the apoptosis of VAFs, whereas FoxO1 promotes VAF apoptosis. Furthermore, the inhibitory effect of SIRT1 on VAF apoptosis is partly mediated by the deacetylation of FoxO1.

Paeoniflorin attenuates pressure overload-induced cardiac remodeling via inhibition of TGFβ/Smads and NF-κB pathways

Cardiac remodeling is a key determinant in the clinical course and outcome of heart failure and characterized by cardiac hypertrophy, fibrosis, cardiomyocyte apoptosis and inflammation. The anti-inflammatory, anti-apoptotic and anti-fibrotic effects of paeoniflorin have been identified in various types of tissue and cells. However, the role of paeoniflorin in cardiac remodeling remains unclear. We performed aortic banding (AB) in mice to induce a cardiac remodeling model in response to pressure overload. Paeoniflorin (20 mg/kg) was administered by daily intraperitoneal (i.p.) injection. Paeoniflorin treatment promoted the survival rate and improved cardiac function of mice at 8 weeks post surgery. AB-induced cardiac hypertrophy, as assessed by heart weight, gross heart, HE and WGA staining, cross-sectional area of cardiomyocyte and mRNA expresssion of hypertrophic makers, was attenuated by paeoniflorin. Paeoniflorin also inhibited collagen deposition, expression of TGFβ, CTGF, collagen Iα and collagen IIIα, and phosphorylation of Smad2 and Smad3 in the heart exposed to pressure overload. Cardiomyocyte apoptosis and induction of Bax and cleaved caspase3 in response to AB were suppressed by paeoniflorin. Furthermore, paeoniflorin decreased the quantity of CD68+ cells, protein levels of TNF-α and IL-1β, and phosphorylation of IκBα and NFκB-p65 in the heart after AB. In conclusion, paeoniflorin attenuated cardiac hypertrophy, fibrosis, apoptosis and inflammation, and improved left ventricular function in pressure overloaded mice. The cardioprotective effect of paeoniflorin is associated with the inhibition of TGFβ/Smads and NF-κB pathways.

Autophagy takes place in mutated p53 neuroblastoma cells in response to hypoxia mimetic CoCl(2)

Solid tumors like neuroblastoma exhibit hypoxic areas, which can lead both to cell death or aggressiveness increase. Hypoxia is a known stress able to induce stabilization of p53, implicated in cell fate regulation. Recently, p53 appeared to be involved in autophagy in an opposite manner, depending on its location: when nuclear, it enhanced transcription of pro-autophagic genes whereas when cytoplasmic, it inhibited the autophagic process. Today, we used cobalt chloride, a hypoxia mimetic that inhibits proteasomal HIF-1 degradation and generates reactive oxygen species (ROS). We focused on CoCl2-induced cell death in a DNA-binding mutated p53 neuroblastoma cell line (SKNBE(2c)). An autophagic signaling was evidenced by an increase of Beclin-1, ATG 5-12, and LC3-II expression whereas the p53(mut) presence decreased with CoCl2 time exposure. Activation of the pathway seemed to protect cells from ROS production and, at least in part, from death. The autophagic inhibitors activated the apoptotic signaling and the death was enhanced. To delineate the eventual implication of the p53(mut) in the autophagic process in response to hypoxia, we monitored signaling in p53(WT)SHSY5Y cells, after either shRNA-p53 down-regulation or transcriptional activity inhibition by pifithrin alpha. We did not detect autophagy neither with p53(wt) nor when p53 was lacking whereas such a response was effective with a mutated or inactivated p53. To conclude, mutated p53 in neuroblastoma cells could be linked with the switch between apoptotic response and cell death by autophagy in response to hypoxic mimetic stress.

Resveratrol attenuates CoCl2-induced cochlear hair cell damage through upregulation of Sirtuin1 and NF-κB deacetylation

The goals of this study were to investigate the effects of hypoxia on cochlear hair cell damage, and to explore the role of sirtuin1 in hypoxia-induced hair cell damage. Cochlear organotypic cultures from postnatal day 4 rats were used in this study. Hypoxia was induced by treating cochlear explants with CoCl2. Cochlear cultures were treated with CoCl2 alone or in combination with the sirtuin1 activator resveratrol and the sirtuin1 inhibitor sirtinol. Hair cell damage was identified by phalloidin staining and imaged using scanning electron microscopy. RT-PCR and Western blot analyses were used to detect the expression of sirtuin1 and acetylated nuclear factor-κB (NF-κB). Low concentrations of CoCl2 (100-200 μM) did not cause an obvious change in the number and morphology of hair cells, whereas higher concentrations of CoCl2 (300-400 μM) induced swelling of hair cells, accompanied by cell loss. Increased sirtuin1 expression was induced by CoCl2 at 100 to 200 μM, but not at 400 μM. NF-κB acetylation was significantly increased in explants treated with 400 μM CoCl2. Pretreatment with resveratrol prevented CoCl2-induced hair cell loss and acetylation of NF-κB. The protective effect of resveratrol was significantly reduced by sirtinol. CoCl2 induces hair cell damage in organotypic cochleae cultures. Resveratrol attenuates CoCl2-induced cochlear hair cell damage possibly via activation of sirtuin1, which deacetylates NF-κB.