Synthetic Derivatives of Natural ent-Kaurane Atractyligenin Disclose Anticancer Properties in Colon Cancer Cells, Triggering Apoptotic Cell Demise.

The antitumor activity of different ent-kaurane diterpenes has been extensively studied. Several investigations have demonstrated the excellent antitumor activity of synthetic derivatives of the diterpene atractyligenin. In this research, a series of new synthetic amides and their 15,19-di-oxo analogues obtained from atractyligenin by modifying the C-2, C-15, and C-19 positions were designed in order to dispose of a set of derivatives with different substitutions at the amidic nitrogen. Using different concentrations of the obtained compounds (10-300 µM) a reduction in cell viability of HCT116 colon cancer cells was observed at 48 h of treatment. All the di-oxidized compounds were more effective than their alcoholic precursors. The di-oxidized compounds had already reduced the viability of two colon cancer cells (HCT116 and Caco-2) at 24 h when used at low doses (2.5-15 µM), while they turned out to be poorly effective in differentiated Caco-2 cells, a model of polarized enterocytes. The data reported here provide evidence that di-oxidized compounds induced apoptotic cell death, as demonstrated by the appearance of condensed and fragmented DNA in treated cells, as well as the activation of caspase-3 and fragmentation of its target PARP-1.

Consumption of Roasted Coffee Leads to Conjugated Metabolites of Atractyligenin in Human Plasma.

Roasted coffee contains atractyligenin-2-O-ß-d-glucoside and 3'-O-ß-d-glucosyl-2'-O-isovaleryl-2-O-ß-d-glucosylatractyligenin, which are ingested with the brew. Known metabolites are atractyligenin, atractyligenin-19-O-ß-d-glucuronide (M1), 2ß-hydroxy-15-oxoatractylan-4α-carboxy-19-O-ß-d-glucuronide (M2), and 2ß-hydroxy-15-oxoatractylan-4α-carboxylic acid-2-O-ß-d-glucuronide (M3), but the appearance and pharmacokinetic properties are unknown. Therefore, first time-resolved quantitative data of atractyligenin glycosides and their metabolites in plasma samples from a pilot human intervention study (n = 10) were acquired. None of the compounds were found in the control samples and before coffee consumption (t = 0 h). After coffee, neither of the atractyligenin glycosides appeared in the plasma, but the aglycone atractyligenin and the conjugated metabolite M1 reached an estimated cmax of 41.9 ± 12.5 and 25.1 ± 4.9 nM, respectively, after 1 h. M2 and M3 were not quantifiable until their concentration enormously increased ≥4 h after coffee consumption, reaching an estimated cmax of 2.5 ± 1.9 and 55.0 ± 57.7 nM at t = 10 h. The data suggest that metabolites of atractyligenin could be exploited to indicate coffee consumption.

Real-Time Visualization of Cytosolic and Mitochondrial ATP Dynamics in Response to Metabolic Stress in Cultured Cells.

Adenosine 5' triphosphate (ATP) is the energy currency of life, which is produced in mitochondria (~90%) and cytosol (less than 10%). Real-time effects of metabolic changes on cellular ATP dynamics remain indeterminate. Here we report the design and validation of a genetically encoded fluorescent ATP indicator that allows for real-time, simultaneous visualization of cytosolic and mitochondrial ATP in cultured cells. This dual-ATP indicator, called smacATPi (simultaneous mitochondrial and cytosolic ATP indicator), combines previously described individual cytosolic and mitochondrial ATP indicators. The use of smacATPi can help answer biological questions regarding ATP contents and dynamics in living cells. As expected, 2-deoxyglucose (2-DG, a glycolytic inhibitor) led to substantially decreased cytosolic ATP, and oligomycin (a complex V inhibitor) markedly decreased mitochondrial ATP in cultured HEK293T cells transfected with smacATPi. With the use of smacATPi, we can also observe that 2-DG treatment modestly attenuates mitochondrial ATP and oligomycin reduces cytosolic ATP, indicating the subsequent changes of compartmental ATP. To evaluate the role of ATP/ADP carrier (AAC) in ATP trafficking, we treated HEK293T cells with an AAC inhibitor, Atractyloside (ATR). ATR treatment attenuated cytosolic and mitochondrial ATP in normoxia, suggesting AAC inhibition reduces ADP import from the cytosol to mitochondria and ATP export from mitochondria to cytosol. In HEK293T cells subjected to hypoxia, ATR treatment increased mitochondrial ATP along with decreased cytosolic ATP, implicating that ACC inhibition during hypoxia sustains mitochondrial ATP but may not inhibit the reversed ATP import from the cytosol. Furthermore, both mitochondrial and cytosolic signals decrease when ATR is given in conjunction with 2-DG in hypoxia. Thus, real-time visualization of spatiotemporal ATP dynamics using smacATPi provides novel insights into how cytosolic and mitochondrial ATP signals respond to metabolic changes, providing a better understanding of cellular metabolism in health and disease.

Direct and indirect targets of carboxyatractyloside, including overlooked toxicity toward nucleoside diphosphate kinase (NDPK) and mitochondrial H+ leak.

CONTEXT: The toxicity of atractyloside/carboxyatractyloside is generally well recognized and commonly ascribed to the inhibition of mitochondrial ADP/ATP carriers, which are pivotal for oxidative phosphorylation. However, these glycosides may 'paralyze' additional target proteins. OBJECTIVE: This review presents many facts about atractyloside/carboxyatractyloside and their plant producers, such as Xanthium spp. (Asteraceae), named cockleburs. METHODS: Published studies and other information were obtained from databases, such as 'CABI - Invasive Species Compendium', 'PubMed', and 'The World Checklist of Vascular Plants', from 1957 to December 2022. The following major keywords were used: 'carboxyatractyloside', 'cockleburs', 'hepatotoxicity', 'mitochondria', 'nephrotoxicity', and 'Xanthium'. RESULTS: In the third decade of the twenty first century, public awareness of the severe toxicity of cockleburs is still limited. Such toxicity is often only perceived by specialists in Europe and other continents. Interestingly, cocklebur is among the most widely distributed invasive plants worldwide, and the recognition of new European stands of Xanthium spp. is provided here. The findings arising from field and laboratory research conducted by the author revealed that (i) some livestock populations may instinctively avoid eating cocklebur while grazing, (ii) carboxyatractyloside inhibits ADP/GDP metabolism, and (iii) the direct/indirect target proteins of carboxyatractyloside are ambiguous. CONCLUSIONS: Many aspects of the Xanthium genus still require substantial investigation/revision in the future, such as the unification of the Latin nomenclature of currently distinguished species, bur morphology status, true fruit (achene) description and biogeography of cockleburs, and a detailed description of the physiological roles of atractyloside/carboxyatractyloside and the toxicity of these glycosides, mainly toward mammals. Therefore, a more careful interpretation of atractyloside/carboxyatractyloside data, including laboratory tests using Xanthium-derived extracts and purified toxins, is needed.

Metabolites of dietary atractyligenin glucoside in coffee drinkers' urine.

Arabica roast coffee contains a substantial amount of water soluble atractyligenin-2-O-ß-d-glucoside, which is ingested by consumption of coffee brew. Metabolomics data suggest this coffee compound is excreted as glucuronides, but the structures of conjugates have not been elucidated so far. We collected coffee drinkers' urine and isolated four metabolites by MS-guided liquid chromatographic fractionation. The structures were investigated by nuclear magnetic resonance (NMR) and time-of-flight mass spectrometry (ToF-MS) and identified as atractyligenin-19-O-ß-d-glucuronide (M1), 2ß-hydroxy-15-oxoatractylan-4α-carboxy-19-O-ß-d-glucuronide (M2), and 2ß-hydroxy-15-oxoatractylan-4α-carboxylic acid-2-O-ß-d-glucuronide (M3). An unconjugated metabolite (M4) was confirmed as atractyligenin. We analyzed spot urines from n = 6 coffee drinking individuals and detected the metabolites M1, M2 and M4 in every sample, and M3 in four out of six samples, suggesting interindividual differences in metabolism.

An in vivo and in vitro model on the protective effect of cilnidipine on contrast-induced nephropathy via regulation of apoptosis and CaMKâ ¡/mPTP pathway.

Contrast-induced nephropathy (CIN) is an acute kidney injury (AKI) observed after the administration of contrast media. Calcium channel blockers (CCBs) have been reported to exert a renal protective effect. This study aims to investigate the role of cilnidipine, a novel CCBs, on CIN by regulating the calcium/calmodulin-dependent protein kinase Ⅱ(CaMKⅡ)/mitochondrial permeability transition pore (mPTP) pathway. Here, iohexol, a representative contrast media, was used to establish CIN model. KN-93 (CaMKⅡ inhibitor) and atractyloside (mPTP opener) were administered in rats, and CaMKⅡ overexpression was used in Human proximal tubular epithelial cells. Markers of renal injury (serum creatinine, blood urea nitrogen, and urinary NAGL), hematoxylin-eosin stain, oxidative stress (ROS, superoxide dismutase [SOD], and malondialdehyde [MDA] levels), cell death (MTT and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling [TUNEL]), mitochondrial function (mPTP, mitochondrial membrane potential [MMP], and ATP) were assessed. Western blots were used to measure the expression levels of Bax/Bcl-2, caspase-3, CaMKⅡ/mPTP signaling pathways. Results showed that cilnidipine markedly improved kidney function, and alleviated tubular cell apoptosis, oxidative stress and mitochondrial damage induced by iohexol in vitro and in vivo. The underlying mechanism may be that cilnidipine relieved CaMKⅡ activation and mPTP opening induced by iohexol. All of these protective effects of cilnidipine were attenuated by CaMKⅡ overexpression and atractyloside (mPTP opener) pretreatment. Moreover, KN-93 (CaMKⅡ inhibitor) treatment showed a similar renal protective effect with cilnidipine, while the protective effect of cilnidipine on kidney in CIN rats was not further suppressed by KN-93 cotreatment. These in vitro and in vivo results point toward the fact that cilnidipine might be a novel therapeutic drug against contrast-induced nephrotoxicity in a CaMKⅡ-dependent manner.

Study on the mechanism of Wuzi-Yanzong-Wan-medicated serum interfering with the mitochondrial permeability transition pore in the GC-2 cell induced by atractyloside.

Wuzi-Yanzong-Wan (WZYZW) is a classic prescription for male infertility. Our previous investigation has demonstrated that it can inhibit sperm apoptosis via affecting mitochondria, but the underlying mechanisms are unclear. The purpose of the present study was to explore the actions of WZYZW on mitochondrial permeability transition pore (mPTP) in mouse spermatocyte cell line (GC-2 cells) opened by atractyloside (ATR). At first, WZYZW-medicated serum was prepared from rats following oral administration of WZYZW for 7 days. GC-2 cells were divided into control group, model group, positive group, as well as 5%, 10%, 15% WZYZW-medicated serum group. Cyclosporine A (CsA) was used as a positive control. 50 µmol·L-1 ATR was added after drugs incubation. Cell viability was assessed using CCK-8. Apoptosis was detected using flow cytometry and TUNEL method. The opening of mPTP and mitochondrial membrane potential (MMP) were detected by Calcein AM and JC-1 fluorescent probe respectively. The mRNA and protein levels of voltage-dependent anion channel 1 (VDAC1), cyclophilin D (CypD), adenine nucleotide translocator (ANT), cytochrome C (Cyt C), caspase 3, 9 were detected by RT-PCR (real time quantity PCR) and Western blotting respectively. The results demonstrated that mPTP of GC-2 cells was opened after 24 hours of ATR treatment, resulting in decreased MMP and increased apoptosis. Pre-protection with WZYZ-medicated serum and CsA inhibited the opening of mPTP of GC-2 cells induced by ATR associated with increased MMP and decreased apoptosis. Moreover, the results of RT-qPCR and WB suggested that WZYZW-medicated serum could significantly reduce the mRNA and protein levels of VDAC1 and CypD, Caspase-3, 9 and CytC, as well as a increased ratio of Bcl/Bax. However, ANT was not significantly affected. Therefore, these findings indicated that WZYZW inhibited mitochondrial mediated apoptosis by attenuating the opening of mPTP in GC-2 cells. WZYZW-medicated serum inhibited the expressions of VDAC1 and CypD and increased the expression of Bcl-2, which affected the opening of mPTP and exerted protective and anti-apoptotic effects on GC-2 cell induced by ATR.

Atractyloside-A ameliorates spleen deficiency diarrhea by interfering with TLR4/MyD88/NF-κB signaling activation and regulating intestinal flora homeostasis.

PURPOSE: Spleen deficiency diarrhea (SDD) is one of the most common types of diarrhea and is linked to intestinal barrier dysfunction and intestinal flora disorders. Atractyloside-A (AA) is one of the main components of Atractylodes Lancea(Thunb.) DC., which acts on the gastrointestinal tract and has therapeutic effects on diarrhea. Folium sennae is a medicinal plant inducing diarrhea; thus, it is one of the effective methods to obtain a diarrhea model. However, the mechanism of action of AA in the treatment of SDD induced by Folium sennae is unclear. METHODS: The intestinal thrapeutic effect of AA on SDD in mice was evaluated by colon pathology. RNA sequencing (RNA-seq) was used to analyze the colonic transcriptome profiles. In addition, 16S rDNA sequencing and fecal microbiota transplantation (FMT) were carried out to verify the role of AA in the regulation of the intestinal flora. RESULTS: The findings revealed that AA alleviated SDD by ameliorating the pathological symptoms while suppressing intestinal inflammatory responses through the TLR4/MyD88/NF-kB signaling and reversing the impairment of mucin synthesis. Furthermore, AA improved the integrity of the intestinal barrier. RNA-seq identified 436 common DEGs out of 1033 DEGs between SDD and AA, and 1933 DEGs between SDD and Ctrl, which are highly enriched in the NF-κB and TNF pathways. Moreover, AA altered the composition of the intestinal flora and FMT reduced SDD. CONCLUSION: AA exerted a therapeutic effect on SDD through the regulation of the intestinal flora and the inflammation by interfering with the TLR4/MyD88/NF-κB signaling pathway.

Investigating the Broad Matrix-Gate Network in the Mitochondrial ADP/ATP Carrier through Molecular Dynamics Simulations.

The mitochondrial ADP/ATP carrier (AAC) exports ATP and imports ADP through alternating between cytosol-open (c-) and matrix-open (m-) states. The salt bridge networks near the matrix side (m-gate) and cytosol side (c-gate) are thought to be crucial for state transitions, yet our knowledge on these networks is still limited. In the current work, we focus on more conserved m-gate network in the c-state AAC. All-atom molecular dynamics (MD) simulations on a variety of mutants and the CATR-AAC complex have revealed that: (1) without involvement of other positive residues, the charged residues from the three Px[DE]xx[KR] motifs only are prone to form symmetrical inter-helical network; (2) R235 plays a determinant role for the asymmetry in m-gate network of AAC; (3) R235 significantly strengthens the interactions between H3 and H5; (4) R79 exhibits more significant impact on m-gate than R279; (5) CATR promotes symmetry in m-gate mainly through separating R234 from D231 and fixing R79; (6) vulnerability of the H2-H3 interface near matrix side could be functionally important. Our results provide new insights into the highly conserved yet variable m-gate network in the big mitochondrial carrier family.

Knockdown of forkhead box protein P1 alleviates hypoxia reoxygenation injury in H9c2 cells through regulating Pik3ip1/Akt/eNOS and ROS/mPTP pathway.

Forkhead box protein P1 (Foxp1) exerts an extensive array of physiological and pathophysiological impacts on the cardiovascular system. However, the exact function of myocardial Foxp1 in myocardial ischemic reperfusion injury (MIRI) stays largely vague. The hypoxia reoxygenation model of H9c2 cells (the rat ventricular myoblasts) closely mimics myocardial ischemia-reperfusion injury. This report intends to research the effects and mechanisms underlying Foxp1 on H9c2 cells in response to hypoxia (12 h)/reoxygenation (4 h) (HR) stimulation. Expressions of Foxp1 and Phosphatidylinositol 3-kinase interacting protein 1 (Pik3ip1) were both upregulated in ischemia/reperfusion (IR)/HR-induced injury. Stimulation through HR led to marked increases in cellular apoptosis, mitochondrial dysfunction, and superoxide generation in H9c2 cells, which were rescued with knockdown of Foxp1 by siRNA. Silence of Foxp1 depressed expression of Pik3ip1 directly activated the PI3K/Akt/eNOS pathway and promoted nitric oxide (NO) release. Moreover, the knockdown of Foxp1 blunted HR-induced enhancement of reactive oxygen species (ROS) generation, thus alleviating excessive persistence of mitochondrial permeability transition pore (mPTP) opening and decreased mitochondrial apoptosis-associated protein expressions in H9c2 cells. Meanwhile, these cardioprotective effects can be abolished by LY294002, NG-nitro-L-arginine methyl ester (L-NAME), and Atractyloside (ATR), respectively. In summary, our findings indicated that knockdown of Foxp1 prevented HR-induced encouragement of apoptosis and oxidative stress via PI3K/Akt/eNOS signaling activation by targeting Pik3ip1 and improved mitochondrial function by inhibiting ROS-mediated mPTP opening. Inhibition of Foxp1 may be a promising therapeutic avenue for MIRI.

Study on the mechanism of Wuzi-Yanzong-Wan-medicated serum interfering with the mitochondrial permeability transition pore in the GC-2 cell induced by atractyloside / 中国天然药物

Wuzi-Yanzong-Wan (WZYZW) is a classic prescription for male infertility. Our previous investigation has demonstrated that it can inhibit sperm apoptosis via affecting mitochondria, but the underlying mechanisms are unclear. The purpose of the present study was to explore the actions of WZYZW on mitochondrial permeability transition pore (mPTP) in mouse spermatocyte cell line (GC-2 cells) opened by atractyloside (ATR). At first, WZYZW-medicated serum was prepared from rats following oral administration of WZYZW for 7 days. GC-2 cells were divided into control group, model group, positive group, as well as 5%, 10%, 15% WZYZW-medicated serum group. Cyclosporine A (CsA) was used as a positive control. 50 μmol·L-1 ATR was added after drugs incubation. Cell viability was assessed using CCK-8. Apoptosis was detected using flow cytometry and TUNEL method. The opening of mPTP and mitochondrial membrane potential (MMP) were detected by Calcein AM and JC-1 fluorescent probe respectively. The mRNA and protein levels of voltage-dependent anion channel 1 (VDAC1), cyclophilin D (CypD), adenine nucleotide translocator (ANT), cytochrome C (Cyt C), caspase 3, 9 were detected by RT-PCR (real time quantity PCR) and Western blotting respectively. The results demonstrated that mPTP of GC-2 cells was opened after 24 hours of ATR treatment, resulting in decreased MMP and increased apoptosis. Pre-protection with WZYZ-medicated serum and CsA inhibited the opening of mPTP of GC-2 cells induced by ATR associated with increased MMP and decreased apoptosis. Moreover, the results of RT-qPCR and WB suggested that WZYZW-medicated serum could significantly reduce the mRNA and protein levels of VDAC1 and CypD, Caspase-3, 9 and CytC, as well as a increased ratio of Bcl/Bax. However, ANT was not significantly affected. Therefore, these findings indicated that WZYZW inhibited mitochondrial mediated apoptosis by attenuating the opening of mPTP in GC-2 cells. WZYZW-medicated serum inhibited the expressions of VDAC1 and CypD and increased the expression of Bcl-2, which affected the opening of mPTP and exerted protective and anti-apoptotic effects on GC-2 cell induced by ATR.

The newborn Fmr1 knockout mouse: a novel model of excess ubiquinone and closed mitochondrial permeability transition pore in the developing heart.

BACKGROUND: Mitochondrial permeability transition pore (mPTP) closure triggers cardiomyocyte differentiation during development while pathological opening causes cell death during myocardial ischemia-reperfusion and heart failure. Ubiquinone modulates the mPTP; however, little is known about its mechanistic role in health and disease. We previously found excessive proton leak in newborn Fmr1 KO mouse forebrain caused by ubiquinone deficiency and increased open mPTP probability. Because of the physiological differences between the heart and brain during maturation, we hypothesized that developing Fmr1 KO cardiomyocyte mitochondria would demonstrate dissimilar features. METHODS: Newborn male Fmr1 KO mice and controls were assessed. Respiratory chain enzyme activity, ubiquinone content, proton leak, and oxygen consumption were measured in cardiomyocyte mitochondria. Cardiac function was evaluated via echocardiography. RESULTS: In contrast to controls, Fmr1 KO cardiomyocyte mitochondria demonstrated increased ubiquinone content and decreased proton leak. Leak was cyclosporine (CsA)-sensitive in controls and CsA-insensitive in Fmr1 KOs. There was no difference in absolute mitochondrial respiration or cardiac function between strains. CONCLUSION: These findings establish the newborn Fmr1 KO mouse as a novel model of excess ubiquinone and closed mPTP in the developing heart. Such a model may help provide insight into the biology of cardiac development and pathophysiology of neonatal heart failure. IMPACT: Ubiquinone is in excess and the mPTP is closed in the developing FXS heart. Strengthens evidence of open mPTP probability in the normally developing postnatal murine heart and provides new evidence for premature closure of the mPTP in Fmr1 mutants. Establishes a novel model of excess CoQ and a closed pore in the developing heart. Such a model will be a valuable tool used to better understand the role of ubiquinone and the mPTP in the neonatal heart in health and disease.

A Single Cysteine Residue in the Translocation Pathway of the Mitosomal ADP/ATP Carrier from Cryptosporidium parvum Confers a Broad Nucleotide Specificity.

Cryptosporidiumparvum is a clinically important eukaryotic parasite that causes the disease cryptosporidiosis, which manifests with gastroenteritis-like symptoms. The protist has mitosomes, which are organelles of mitochondrial origin that have only been partially characterized. The genome encodes a highly reduced set of transport proteins of the SLC25 mitochondrial carrier family of unknown function. Here, we have studied the transport properties of one member of the C. parvum carrier family, demonstrating that it resembles the mitochondrial ADP/ATP carrier of eukaryotes. However, this carrier has a broader substrate specificity for nucleotides, transporting adenosine, thymidine, and uridine di- and triphosphates in contrast to its mitochondrial orthologues, which have a strict substrate specificity for ADP and ATP. Inspection of the putative translocation pathway highlights a cysteine residue, which is a serine in mitochondrial ADP/ATP carriers. When the serine residue is replaced by cysteine or larger hydrophobic residues in the yeast mitochondrial ADP/ATP carrier, the substrate specificity becomes broad, showing that this residue is important for nucleotide base selectivity in ADP/ATP carriers.

CMap analysis identifies Atractyloside as a potential drug candidate for type 2 diabetes based on integration of metabolomics and transcriptomics.

BACKGROUND: This research aimed at exploring the mechanisms of alterations of metabolites and pathways in T2D from the perspective of metabolomics and transcriptomics, as well as uncovering novel drug candidate for T2D treatment. METHODS: Metabolites in human plasma from 42 T2D patients and 45 non-diabetic volunteers were detected by liquid chromatography-mass spectrometer (LC-MS). Microarray dataset of the transcriptome was obtained from Gene Expression Omnibus (GEO) database. Kyoto Encyclopedia of Genes and Genomes (KEGG) database was used to conduct pathway enrichment analysis. Connectivity Map (CMap) was employed to select potential drugs for T2D therapy. In vivo assay was performed to verify above findings. The protein expression levels of ME1, ME2 and MDH1 were detected by Western blot to determine the status of NAD/NADH cofactor system. RESULTS: In our study, differentially expressed metabolites were selected out between healthy samples and T2D samples with selection criteria P value < .05, |Fold Change| > 2, including N-acetylglutamate and Malate. Genes set enrichment analysis (GSEA) revealed that 34 pathways were significantly enriched in T2D. Based on CMap analysis and animal experiments, Atractyloside was identified as a potential novel drug for T2D treatment via targeting ME1, ME2 and MDH1 and regulating the NAD/NADH cofactor system. CONCLUSION: The present research revealed differentially expressed metabolites and genes, as well as significantly altered pathways in T2D via an integration of metabolomics, transcriptomics and CMap analysis. It was also demonstrated that comprehensive analysis based on metabolomics and transcriptomics was an effective approach for identification and verification of metabolic biomarkers and alternated pathways.

Limb Ischemic Postconditioning Alleviates Postcardiac Arrest Syndrome through the Inhibition of Mitochondrial Permeability Transition Pore Opening in a Porcine Model.

OBJECTIVE: Previously, the opening of mitochondrial permeability transition pore (mPTP) was confirmed to play a key role in the pathophysiology of postcardiac arrest syndrome (PCAS). Recently, we demonstrated that limb ischemic postconditioning (LIpostC) alleviated cardiac and cerebral injuries after cardiac arrest and resuscitation. In this study, we investigated whether LIpostC would alleviate the severity of PCAS through inhibiting mPTP opening. METHODS: Twenty-four male domestic pigs weighing 37 ± 2 kg were randomly divided into three groups: control, LIpostC, and LIpostC+atractyloside (Atr, the mPTP opener). Atr (10 mg/kg) was intravenously injected 30 mins prior to the induction of cardiac arrest. The animals were subjected to 10 mins of untreated ventricular fibrillation and 5 mins of cardiopulmonary resuscitation. Coincident with the beginning of cardiopulmonary resuscitation, LIpostC was induced by four cycles of 5 mins of limb ischemia and then 5 mins of reperfusion. The resuscitated animals were monitored for 4 hrs and observed for an additional 68 hrs. RESULTS: After resuscitation, systemic inflammation and multiple organ injuries were observed in all resuscitated animals. However, postresuscitation systemic inflammation was significantly milder in the LIpostC group than in the control group. Myocardial, lung, and brain injuries after resuscitation were significantly improved in the LIpostC group compared to the control group. Nevertheless, pretreatment with Atr abolished all the protective effects induced by LIpostC. CONCLUSION: LIpostC significantly alleviated the severity of PCAS, in which the protective mechanism was associated with the inhibition of mPTP opening.

Simultaneous quantification of atractyloside and carboxyatractyloside in rat plasma by LC-MS/MS: Application to a pharmacokinetic study after oral administration of Xanthii Fructus extract.

Xanthii Fructus is extensively used as an herbal medicine. Ingestion of this herb is associated with severe hepatotoxicity and nephrotoxicity. Atractyloside and carboxyatractyloside are two dominative toxic constituents in Xanthii Fructus. However, their pharmacokinetic study is lacking. In this study, a novel high-performance liquid chromatography-tandem mass spectrometry method was developed to simultaneously quantify the rat plasma concentrations of atractyloside and carboxyatractyloside. After protein precipitation, the analytes were chromatographic separated on a ZORBAX Eclipse Plus column (2.1 × 150 mm id, 5 µm) under gradient elute. In the negative electrospray ionization mode, the transitions at m/z 725.3→645.4 for atractyloside, m/z 769.3→689.4 for carboxyatractyloside, and m/z 479.2→121.1 for paeoniflorin (the internal standard) were acquired by multiple reaction monitoring. This analytical method showed good linearity over 1-500 ng/mL for atractyloside and 2-500 ng/mL for carboxyatractyloside with acceptable precision and accuracy. No matrix effect, instability and carryover occurred in the analysis procedure. The extraction recoveries were greater than 85.0%. This method was applied to a preliminary pharmacokinetic study by orally administering Xanthii Fructus extract (9 g/kg) to rats, which was useful to evaluate the role of these two compounds in Xanthii Fructus-induced toxicity.

Nutritional Preconditioning of Apigenin Alleviates Myocardial Ischemia/Reperfusion Injury via the Mitochondrial Pathway Mediated by Notch1/Hes1.

Apigenin (Api), a natural flavone found in high amounts in several herbs, has shown potent cardioprotective effects in clinical studies, although the underlying mechanisms are not clear. We hypothesized that Api protects the myocardium from simulated ischemia/reperfusion (SI/R) injury via nutritional preconditioning (NPC). Rats fed with Api-containing food showed improvement in cardiac functions; lactate dehydrogenase (LDH) and creatine phosphokinase (CPK) activities; infarct size; apoptosis rates; malondialdehyde (MDA) levels; caspase-3, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities; and ferric reducing antioxidant power (FRAP) compared to those fed standard chow following SI/R injury. In addition, Api pretreatment significantly improved the viability, decreased the LDH activity and intracellular reactive oxygen species (ROS) generation, alleviated the loss of mitochondrial membrane potential (MMP), prevented the opening of the mitochondrial permeability transition pore (mPTP), and decreased the caspase-3 activity, cytochrome c (Cyt C) release, and apoptosis induced by SI/R in primary cardiomyocytes. Mechanistically, Api upregulated Hes1 expression and was functionally neutralized by the Notch1 γ-secretase inhibitor GSI, as well as the mPTP opener atractyloside (Atr). Taken together, Api protected the myocardium against SI/R injury via the mitochondrial pathway mediated by the Notch1/Hes1 signaling pathway.

Bioavailability and Biological Effects of 2- O-ß-d-Glucopyranosyl-carboxyatractyligenin from Green Coffee in Caenorhabditis elegans.

Targeted analysis of Coffea arabica and Coffea canephora green coffees (total sample size n = 57) confirmed 2- O-ß-d-glucopyranosyl-carboxyatractyligenin (6) as the quantitatively dominating carboxyatractyligenin derivative. Its abundance in Arabicas (2425 ± 549 nmol/g, n = 48) exceeded that in Robustas (34 ± 12 nmol/g, n = 9) roughly by a factor of 70. Coffee processing involving heat (e.g., steam treatment and decaffeination) reduced concentrations of 6 and increased those of the decarboxylated derivative. The bioavailability of compound 6 in Caenorhabditis elegans was demonstrated by ultraperformance liquid chromatography-tandem mass spectrometry analysis of extracts prepared from nematode cultures incubated in a liquid medium containing 6. A toxicity assay performed to assess the impact of 6 in vivo showed a 20-fold higher median lethal dose (LD50 = 11.7 ± 1.2 mM) concentration compared to that of the known phytotoxic adenine-nucleotide transporters inhibitor carboxyatractyloside (2, LD50 = 0.61 ± 0.05 mM), whereas 1 mM 6 and 0.1 mM 2 were sufficient to decrease the survival of wild type C. elegans, already 10-20-fold lower doses reduced reproduction. Because the insulin/insulin-like growth factors signaling cascade (IIS) is a key regulator of life span and stress resistance, the impact of compound 6 on the survival of long-living daf-2 C. elegans was tested. As the susceptibility of these nematodes to 6 was as high as that in wild type, an impact on central metabolic processes independent of IIS was suggested. Analysis of the in vivo adenosine triphosphate (ATP) content of adult C. elegans revealed no changes after 1 and 24 h, but a 50% reduction after treatment with 1 mM 6 during the entire postembryonic development. These data speak for a developmental-stage-dependent modulation of the ATP pool by 6.

Atractyligenin, a terpenoid isolated from coffee silverskin, inhibits cutaneous photoaging.

Ultraviolet (UV) light exposure-induced photoaging of the skin is a multifactorial process involving both extrinsic and intrinsic cellular mechanisms. Several naturally occurring products are known to confer protection against UV light-induced skin damage. Our preliminary studies confirmed that the ethyl acetate fraction of coffee silverskin exhibits inhibitory effects on matrix metalloproteases (MMPs). Furthermore, we previously isolated and identified atractyligenin, which has MMP-inhibitory activity, from the silverskin ethyl acetate fraction. The aim of this study was to elucidate the anti-photoaging effects of atractyligenin on human dermal fibroblasts and the underlying mechanism. Human dermal fibroblasts were exposed to 8 J/cm2 UVA radiation, and cell viability was analyzed by MTT assay. The fluorescent dye 2', 7'-dichlorodihydrofluorescein diacetate (H2DCF-DA) was used to measure the intracellular reactive oxygen species (ROS) levels. Our study showed that atractyligenin significantly suppressed the expression of UVA-induced MMPs by inhibiting intracellular ROS production. Atractyligenin treatment reduced c-Jun phosphorylation and c-Fos expression by inhibiting the mitogen-activated protein kinase (MAPK) signaling pathway activated by UVA irradiation. Additionally, treatment with atractyligenin contributed to the homeostasis of collagen by restoring the loss of collagen absorption-related receptor Endo180 and altered fibroblast morphology induced by UVA irradiation. These results indicate that atractyligenin isolated from coffee silverskin inhibits multiple pathways in the human skin photoaging process and is thus a potential candidate for treatment or prevention of photoaging.

Chemometrics coupled with UPLC-MS/MS for simultaneous analysis of markers in the raw and processed Fructus Xanthii, and application to optimization of processing method by BBD design.

BACKGROUND: As a widely used toxic traditional herbal medicine, the quality of the Fructus Xanthii must be well controlled to ensure the clinical therapeutic efficacy and safety. AIMS: A rapid, and sensitive using ultra-high performance liquid chromatography to triple quadrupole tandem mass spectrometry (UPLC-MS/MS) in selected reaction monitoring (SRM) mode was developed and validated for simultaneous quantitation of determination active and toxic ingredients form processed by stir-frying and raw materials of Fructus Xanthii. METHODS: Chromatographic separation of all targeted compound was performed on Waters ACQUITY UPLC HSS T3 column (50 mm × 2.1 mm, 1.8 µm). Moreover, the method was successfully applied in thirty-six samples of Fructus Xanthii collected from different sources in China. The processing method was optimized through Box-Behnken statistical design and response surface methodology. RESULTS: In this work, chemometrics was able to successfully discriminate and classify among samples. The optimal incubation conditions were as follows: under heating in a pot at 295 °C, medicine at 120 °C for 11.0 min with flipping frequently. CONCLUSIONS: Therefore, the established UPLC-QQQ-MS method in combination with chemometric analysis provides a rapid, flexible and reliable method for quality assessment of Fructus Xanthii. Importantly, the optimized experimental value of the processing process provides the basis for future research.