Lactate-to-albumin ratio and cholesterol levels predict neurological outcome in cardiac arrest survivors.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) increases lactate levels and reduces albumin levels on admission and tends to lead to a poor neurological prognosis. In our experience, reduced cholesterol levels predict poor neurological prognosis. However, the relationship between cholesterol levels and neurological prognosis in OHCA survivors remains unclear. METHODS: This retrospective observational study included data from January 2015 to June 2023 on 219 OHCA survivors at our intensive care unit. Patients were categorized into two groups based on cerebral functional classification (CPC) scores: Group A (CPC score of 1 or 2), including patients with a favorable neurological outcome, and Group B (CPC scores of 3 to 5), comprising those with a poor neurological outcome. We analyzed their lactate, albumin levels, and lipid profiles measured at 6 h after resuscitation. A model to predict the neurological prognosis of admission of OHCA survivors was developed. RESULTS: Approximately 40% of the patients had favorable neurological outcomes at the 30-day follow-up. The lactate-to-albumin ratio (LAR) was significantly lower in Group A than in Group B (3.1 vs. 5.0 mmol/dag, p < 0.001). However, the albumin, total cholesterol, and high-density lipoprotein (HDL) cholesterol levels were significantly higher in Group A than in Group B (3.6 vs. 2.9 g/dL, 166.1 vs. 131.4 mg/dL, and 38.8 vs. 29.7 mg/dL, respectively, p < 0.001). Favorable neurological outcome was indicated at the following thresholds: LAR < 3.7 mmol/dag, albumin level > 3.1 g/dL, total cholesterol level > 146.4 mg/dL, and HDL-cholesterol level > 31.9 mg/dL. These findings underscore the high sensitivity and negative predictive value of the biomarkers. Furthermore, the area under the curve values for LAR, albumin, total cholesterol, and HDL-cholesterol levels were 0.70, 0.75, 0.71, and 0.71, respectively. The corresponding odds ratios were 3.37, 7.08, 3.67, and 3.94, respectively. CONCLUSIONS: The LAR, albumin, total cholesterol, and HDL-cholesterol levels measured on admission may predict neurological prognosis in OHCA survivors. Thus, routine practice should include the measurement of these biomarkers at 6 h after resuscitation, especially in patients with a lactate level of > 5 mmol/L. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT02633358.

Dysregulation of Immune Cell Subpopulations in Atypical Hemolytic Uremic Syndrome.

Atypical hemolytic uremic syndrome (aHUS) is a rare, life-threatening thrombotic microangiopathy. Definitive biomarkers for disease diagnosis and activity remain elusive, making the exploration of molecular markers paramount. We conducted single-cell sequencing on peripheral blood mononuclear cells from 13 aHUS patients, 3 unaffected family members of aHUS patients, and 4 healthy controls. We identified 32 distinct subpopulations encompassing 5 B-cell types, 16 T- and natural killer (NK) cell types, 7 monocyte types, and 4 other cell types. Notably, we observed a significant increase in intermediate monocytes in unstable aHUS patients. Subclustering analysis revealed seven elevated expression genes, including NEAT1, MT-ATP6, MT-CYB, VIM, ACTG1, RPL13, and KLRB1, in unstable aHUS patients, and four heightened expression genes, including RPS27, RPS4X, RPL23, and GZMH genes, in stable aHUS patients. Additionally, an increase in the expression of mitochondria-related genes suggested a potential influence of cell metabolism on the clinical progression of the disease. Pseudotime trajectory analysis revealed a unique immune cell differentiation pattern, while cell-cell interaction profiling highlighted distinctive signaling pathways among patients, family members, and controls. This single-cell sequencing study is the first to confirm immune cell dysregulation in aHUS pathogenesis, offering valuable insights into molecular mechanisms and potential new diagnostic and disease activity markers.

The functional interplay of lncRNA EGOT and HuR regulates hypoxia-induced autophagy in renal tubular cells.

Autophagy, an important cellular homeostatic mechanism regulates cell survival under stress and protects against acute kidney injury. However, the role of long noncoding RNA (lncRNA) in autophagy regulation in renal tubular cells (HK-2) is unclear. The study was aimed to understand the importance of lncRNA in hypoxia-induced autophagy in HK-2 cells. LncRNA eosinophil granule ontogeny transcript (EGOT) was identified as autophagy-associated lncRNA under hypoxia. The lncRNA EGOT expression was significantly downregulated in renal tubular cells during hypoxia-induced autophagy. Gain- and loss-of-EGOT functional studies revealed that EGOT overexpression reduced autophagy by downregulation of ATG7, ATG16L1, LC3II expressions and LC 3 puncta while EGOT knockdown reversed the suppression of autophagy. Importantly, RNA-binding protein, (ELAVL1)/Hu antigen R (HuR) binds and stabilizes the EGOT expression under normoxia and ATG7/16L1 expressions under hypoxia. Furthermore, HuR mediated stabilization of ATG7/16L1 expressions under hypoxia causes a decline in EGOT levels and thereby promotes autophagy. Altogether, the study first reveals the functional interplay of lncRNA EGOT and HuR on the posttranscriptional regulation of the ATG7/16L1 expressions. Thus, the HuR/EGOT/ATG7/16L1 axis is crucial for hypoxia-induced autophagy in renal tubular cells.

Skin autofluorescence is associated with inappropriate left ventricular mass and diastolic dysfunction in subjects at risk for cardiovascular disease.

BACKGROUND: Enhanced advanced glycation end products deposition within myocardial tissue may cause diastolic dysfunction. However, whether this is related to left ventricular hypertrophy or inappropriate left ventricular mass remains unclear. METHODS: We prospectively enrolled 139 subjects at risk for cardiovascular diseases. We used echocardiography for measurements of left ventricular mass and cardiac systolic and diastolic functional parameters. An advanced glycation end product reader was applied for measurements of skin autofluorescence values. Comparisons of left ventricular mass and echocardiographic parameters between the higher and lower skin autofluorescence groups were analyzed. RESULTS: Compared with the lower skin autofluorescence group, left ventricular mass index and the ratio of observed left ventricular mass/predicted left ventricular mass (oLVM/pLVM) was significantly higher in the higher skin autofluorescence group (61.22 ± 17.76 vs. 47.72 ± 11.62, P < 0.01, 1.62 ± 0.38 vs. 1.21 ± 0.21, P < 0.01). After adjustment for potential confounding factors, skin autofluorescence was an independent factor for left ventricular mass index (ß = 0.32, P < 0.01) and the ratio of oLVM/pLVM (ß = 0.41, P < 0.01). Skin autofluorescence ≥2.35 arbitrary unit predicted left ventricular hypertrophy at a sensitivity of 58.8%, and a specificity of 73.0% (P < 0.01). Skin autofluorescence ≥2.25 arbitrary unit predicted inappropriate left ventricular mass at a sensitivity of 71.1%, and a specificity of 83.9% (P < 0.01). Skin autofluorescence was positively correlated with E/E', an indicator for diastolic dysfunction (r = 0.21, P = 0.01). CONCLUSIONS: Skin autofluorescence is a useful tool for detecting left ventricular hypertrophy, inappropriate left ventricular mass and diastolic dysfunction.

Cellular apoptosis and cardiac dysfunction in STZ-induced diabetic rats attenuated by anthocyanins via activation of IGFI-R/PI3K/Akt survival signaling.

Anthocyanins are known cyto-protective agents against various stress conditions. In this study cardio-protective effect of anthocyanins from black rice against diabetic mellitus (DM) was evaluated using a streptozotocin (STZ)-induced DM rat model. Five-week-old male Wistar rats were administered with STZ (55 mg kg-1 , IP) to induce DM; rats in the treatment group received 250 mg oral anthocyanin/kg/day during the 4-week treatment period. DM and the control rats received normal saline through oral gavage. The results reveal that STZ-induced DM elevates myocardial apoptosis and associated proapoptotic proteins but down-regulates the proteins of IGF1R mediated survival signaling mechanism. Furthermore, the functional parameters such as the ejection-fraction and fraction-shortening in the DM rat hearts declined considerably. However, the rats treated with anthocyanins significantly reduced apoptosis and the associated proapoptotic proteins and further increased the survival signals to restore the cardiac functions in DM rats. Anthocyanin supplementation enhances cardiomyocyte survival and restores cardiac function.

Angiogenesis Inhibitors and Anti-Inflammatory Agents from Phoma sp. NTOU4195.

Seven new polyketides, phomaketides A-E (1-5) and pseurotins A3 (6) and G (7), along with the known compounds FR-111142, pseurotins A, A1, A2, D, and F2, 14-norpseurotin A, α-carbonylcarbene, tyrosol, cyclo(-l-Pro-l-Leu), and cyclo(-l-Pro-l-Phe), were purified from the fermentation broth and mycelium of the endophytic fungal strain Phoma sp. NTOU4195 isolated from the marine red alga Pterocladiella capillacea. The structures were established through interpretation of spectroscopic data. The antiangiogenic and anti-inflammatory effects of 1-7 and related analogues were evaluated using human endothelial progenitor cells (EPCs) and lipopolysaccharide (LPS)-activated murine macrophage RAW264.7 cells, respectively. Of the compounds tested, compound 1 exhibited the most potent antiangiogenic activity by suppressing the tube formation of EPCs with an IC50 of 8.1 µM, and compound 3 showed the most selective inhibitory activity of LPS-induced NO production in RAW264.7 macrophages with an IC50 value of 8.8 µM.

Diterpene glycosides and polyketides from Xylotumulus gibbisporus.

Four new tetracyclic diterpene glycosides, namely, sordarins C-F (1-4), and three new γ-lactone polyketides, namely, xylogiblactones A-C (5-7), along with sordarin were isolated from the ethyl acetate extracts of the fermented broths of Xylotumulus gibbisporus YMJ863. The structures of 1-7 were elucidated on the basis of spectroscopic data analyses. The configurations of 1-4 were deduced by NOESY, molecular modeling, and comparison with the literature. The relative configurations of 5-7 were deduced by X-ray crystallographic analysis of 5. Compounds 1-5 and sordarin were evaluated in an antifungal assay using Candida albicans ATCC 18804, C. albicans ATCC MYA-2876, and Saccharomyces cerevisiae ATCC 2345, and only sordarin exhibited significant antifungal activities against these fungal strains, with MIC values of 64.0, 32.0, and 32.0 µg/mL, respectively. The effect of compounds 1-7 and sordarin on the inhibition of NO production in lipopolysaccharide-activated murine macrophages was also evaluated. Compounds 2 and sordarin inhibited NO production with IC50 values of 327.2±46.6 and 157.1±24.1 µM, respectively.

Impact of mechanical circulatory support on out-of-hospital cardiac arrest outcomes stratified by vasoactive-inotropic score: A retrospective cohort study.

Aims: To assess whether mechanical circulatory support (MCS), including intra-aortic balloon pump (IABP) or veno-arterial extracorporeal membrane oxygenation (ECMO), can help improve neurological outcomes in patients with out-of-hospital cardiac arrest (OHCA). Methods: This is a retrospective observational cohort study performed in China Medical University Hospital, Taichung, Taiwan. Adult patients with OHCA admitted between January 2015 and June 2023. Quantitative score of vasoactive-inotropic agents and qualitative interventions of MCS, including IABP and ECMO after OHCA. Multivariate regression evaluated the efficacy of each MCS approach in patients stratified by the vasoactive-inotropic score (VIS). Results: A total of 334 patients were included and analyzed, 122 (36.5%) had favorable neurological outcomes and 215 (64.4%) survived ≥90 days. These patients were stratified by VIS: 0-25, 26-100, 101-250, and >250. In patients with a VIS > 100, ECMO with or without IABP ensured favorable neurological outcomes and survival after OHCA compared to non-MCS interventions (p < 0.001). For patients with a VIS ≤ 100, IABP alone was beneficial, with no significant outcome difference from non-MCS interventions (p > 0.05). Conclusions: ECMO with or without IABP therapy may improve post-OHCA neurological outcomes and survival in patients with an expected VIS-24 h > 100 (e.g., epinephrine dose reaches 3 mg during CPR).

Biochemical and functional characterization of charge-defined subfractions of high-density lipoprotein from normal adults.

High-density lipoprotein (HDL) is regarded as atheroprotective because it provides antioxidant and anti-inflammatory benefits and plays an important role in reverse cholesterol transport. In this paper, we outline a novel methodology for studying the heterogeneity of HDL. Using anion-exchange chromatography, we separated HDL from 6 healthy individuals into five subfractions (H1 through H5) with increasing charge and evaluated the composition and biologic activities of each subfraction. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis showed that apolipoprotein (apo) AI and apoAII were present in all 5 subfractions; apoCI was present only in H1, and apoCIII and apoE were most abundantly present in H4 and H5. HDL-associated antioxidant enzymes such as lecithin-cholesterol acyltransferase, lipoprotein-associated phospholipase A2, and paraoxonase 1 were most abundant in H4 and H5. Lipoprotein isoforms were analyzed in each subfraction by using matrix-assisted laser desorption-time-of-flight mass spectrometry. To quantify other proteins in the HDL subfractions, we used the isobaric tags for the relative and absolute quantitation approach followed by nanoflow liquid chromatography-tandem mass spectrometry analysis. Most antioxidant proteins detected were found in H4 and H5. The ability of each subfraction to induce cholesterol efflux from macrophages increased with increasing HDL electronegativity, with the exception of H5, which promoted the least efflux activity. In conclusion, anion-exchange chromatography is an attractive method for separating HDL into subfractions with distinct lipoprotein compositions and biologic activities. By comparing the properties of these subfractions, it may be possible to uncover HDL-specific proteins that play a role in disease.

Anti-inflammatory components from the root of Solanum erianthum.

Two new norsesquiterpenoids, solanerianones A and B (1-2), together with nine known compounds, including four sesquiterpenoids, (-)-solavetivone (3), (+)-anhydro-ß-rotunol (4), solafuranone (5), lycifuranone A (6); one alkaloid, N-trans-feruloyltyramine (7); one fatty acid, palmitic acid (8); one phenylalkanoid, acetovanillone (9), and two steroids, ß-sitosterol (10) and stigmasterol (11) were isolated from the n-hexane-soluble part of the roots of Solanum erianthum. Their structures were elucidated on the basis of physical and spectroscopic data analyses. The anti-inflammatory activity of these isolates was monitored by nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine macrophage RAW264.7 cells. The cytotoxicity towards human lung squamous carcinoma (CH27), human hepatocellular carcinoma (Hep 3B), human oral squamous carcinoma (HSC-3) and human melanoma (M21) cell lines was also screened by using an MTT assay. Of the compounds tested, 3 exhibited the strongest NO inhibition with the average maximum inhibition (Emax) at 100 µM and median inhibitory concentration (IC50) values of 98.23% ± 0.08% and 65.54 ± 0.18 µM, respectively. None of compounds (1-9) was found to possess cytotoxic activity against human cancer cell lines at concentrations up to 30 µM.

Immune responses and safety of COVID-19 vaccination in atypical hemolytic uremic syndrome patients in Taiwan.

Atypical hemolytic uremic syndrome is a rare, life-threatening disorder which can be triggered by COVID 19 infection and COVID 19 vaccination then induce multiple organ failure. Our study is the first to evaluate immune responses to COVID-19 vaccination and safety in a cohort of patients in a local single-center study in Taiwan.. Results indicate that vaccines effectively shield aHUS patients from severe COVID-19 complications without significant safety concerns. A double booster dose for the third vaccine is essential for optimal efficacy. Anti-complement therapy did not influence vaccination effectiveness. Transplant aHUS patients had the lowest immune response titers, indicating a need for additional vaccine doses. Compared to healthcare workers, aHUS patients had poor T-cell responses. We noted a superior trend with mixed-type COVID-19 vaccinations in aHUS patients, while fixed-type mRNA demonstrated better results in healthcare workers. Our findings endorse COVID-19 vaccination as a potent strategy to safeguard aHUS patients from severe complications, emphasizing the importance of vigilant monitoring pre- and post-vaccination.

Electronegative low-density lipoprotein induces cardiomyocyte apoptosis indirectly through endothelial cell-released chemokines.

Cardiomyocyte apoptosis has a critical role in the pathogenesis of heart failure. L5, the most negatively charged subfraction of human plasma low-density lipoprotein (LDL), induces several atherogenic responses in endothelial cells (ECs), including apoptosis. We hypothesized that L5 also contributes to cardiomyocyte apoptosis and studied whether it does so indirectly by inducing the secretion of factors from ECs. We examined apoptosis of rat cardiomyocytes treated with culture-conditioned medium (CCM) of rat ECs that were exposed to L5 or L1 (the least negatively charged LDL subfraction). Apoptosis at early and late time points was twofold greater in cardiomyocytes treated with L5 CCM than in those treated with L1 CCM. The indirect effect of L5 on cardiomyocyte apoptosis was significantly reduced by pretreating ECs with inhibitors of phosphatidylinositol 3-kinase (PI3K) or CXC receptor 2 (CXCR2). Studies with cytokine protein arrays revealed that L5 CCM, but not L1 CCM, contained high levels of ELR(+) CXC chemokines, including lipopolysaccharide-induced chemokine (LIX) and interleukin (IL)-8. The L5-induced release of these chemokines from ECs was abolished by inhibiting the lectin-like oxidized LDL receptor-1 (LOX-1). Addition of recombinant LIX or IL-8 to CCM-free cardiomyocyte cultures increased apoptosis and enhanced production of tumor necrosis factor (TNF)-α and IL-1ß by increasing the translocation of NF-κB into the nucleus; these effects were attenuated by inhibiting PI3K and CXCR2. In conclusion, L5 may indirectly induce cardiomyocyte apoptosis by enhancing secretion of ELR(+) CXC chemokines from ECs, which in turn activate CXCR2/PI3K/NF-κB signaling to increase the release of TNF-α and IL-1ß.

Chewing areca nut increases the risk of coronary artery disease in Taiwanese men: a case-control study.

BACKGROUND: Areca nut chewing has been reported to be associated with obesity, metabolic syndrome, hypertension, and cardiovascular mortality in previous studies. The aim of this study was to examine whether chewing areca nut increases the risk of coronary artery disease (CAD) in Taiwanese men. METHODS: This study is a hospital-based case-control study. The case patients were male patients diagnosed in Taiwan between 1996 and 2009 as having a positive Treadmill exercise test or a positive finding on the Thallium-201 single-photon emission computed tomography myocardial perfusion imaging. The case patients were further evaluated by coronary angiography to confirm their CAD. Obstructive CAD was defined as a ≥ 50% decrease in the luminal diameter of one major coronary artery. The patients who did not fulfill the above criteria of obstructive CAD were excluded.The potential controls were males who visited the same hospital for health check-ups and had a normal electrocardiogram but no history of ischemic heart disease or CAD during the time period that the case patients were diagnosed. The eligible controls were randomly selected and frequency-matched with the case patients based on age. Multiple logistic regression analyses were used to estimate the odds ratio of areca nut chewing and the risk of obstructive CAD. RESULTS: A total of 293 obstructive CAD patients and 720 healthy controls, all men, were analyzed. Subjects who chewed areca nut had a 3.5-fold increased risk (95% CI = 2.0-6.2) of having obstructive CAD than those without, after adjusting for other significant covariates. The dose-response relationship of chewing areca nut and the risk of obstructive CAD was also noted. After adjusting for other covariates, the 2-way additive interactions for obstructive CAD risk were also significant between areca nut use and cigarette smoking, hypertension and dyslipidemia. CONCLUSIONS: Long-term areca nut chewing was an independent risk factor of obstructive CAD in Taiwanese men. Interactive effects between chewing areca nut and cigarette smoking, hypertension, and dyslipidemia were also observed for CAD risk. Further exploration of their underlying mechanisms is necessary.

Inhibitory effects of terpenoids from the fermented broth of the ascomycete Stilbohypoxylon elaeicola YMJ173 on nitric oxide production in RAW264.7 macrophages.

A series of six isopimarane-type diterpene glycosides, along with an eremophilane-type sesquiterpene, i.e., elaeicolasides A-C (1-3, resp.), 16-(α-D-mannopyranosyloxy)isopimar-7-en-19-oic acid (4), hymatoxin K (5), hymatoxin L (6), and elaeicolalactone (7), were isolated from the AcOEt extract of the fermented broth of Stilbohypoxylon elaeicola YMJ173. Among these, 1-3 and 7 are new compounds based on their spectroscopic data and sugar composition analysis. The effects of 1-7 on the inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine macrophage RAW264.7 cells were evaluated. All these compounds inhibited NO production, detected as nitrite in the culture medium, in activated macrophages without any cytotoxicity at a concentration of 100 µM. Among these compounds, 2 showed a significant activity with the average maximum inhibition (E(max)) and median inhibitory concentration (IC(50)) values of 93.3±0.5% and 79.3±0.4 µM, respectively.

Secondary metabolites from the roots of Beilschmiedia tsangii and their anti-inflammatory activities.

Four new endiandric acid analogues, tsangibeilin C (1), tsangibeilin D (2), tricyclotsangibeilin (3) and endiandric acid M (4), one new lignan, beilschminol B (5) and two new sesquiterpenes, (+)-5-hydroxybarbatenal (6) and (4R,5R)-4,5-dihydroxycaryophyll-8(13)-ene (7), together with four known compounds (8-11), were isolated from the roots of Beilschmiedia tsangii (Lauraceae). The structures of 1-7 were determined by spectroscopic techniques. Among the isolates, endiandric acid M (4) exhibited moderate iNOS inhibitory activity, with an IC(50) value of 31.70 µM.

Chemical composition-oriented receptor selectivity of L5, a naturally occurring atherogenic low-density lipoprotein.

Anion-exchange chromatography resolves human plasma low-density lipoprotein (LDL) into 5 subfractions, with increasing negative surface charge in the direction of L1 to L5. Unlike the harmless L1 to L4, the exclusively atherogenic L5 is rejected by the normal LDL receptor (LDLR) but endocytosed into vascular endothelial cells through the lectin-like oxidized LDL receptor-1 (LOX-1). Analysis with SDS-PAGE and 2-dimensional electrophoresis showed that the protein framework of L1 was composed mainly of apolipoprotein (apo) B100, with an isoelectric point (pI) of 6.620. There was a progressively increased association of additional proteins, including apoE (pI 5.5), apoAI (pI 5.4), apoCIII (pI 5.1), and apo(a) (pI 5.5), from L1 to L5. LC/MSE was used to quantify protein distribution in all subfractions. On the basis of weight percentages, L1 contained 99% apoB-100 and trace amounts of other proteins. In contrast, L5 contained 60% apoB100 and substantially increased amounts of apo(a), apoE, apoAI, and apoCIII. The compositional characteristics contribute to L5's electronegativity, rendering it unrecognizable by LDLR. LOX-1, which has a high affinity for negatively charged ligands, is known to mediate the signaling of proinflammatory cytokines. Thus, the chemical composition-oriented receptor selectivity hinders normal metabolism of L5, enhancing its atherogenicity through abnormal receptors, such as LOX-1.

Anti-inflammatory endiandric acid analogues from the roots of Beilschmiedia tsangii.

Bioassay-guided fractionation of roots of Beilschmiedia tsangii led to the isolation of six new endiandric acid analogues: tsangibeilin A (1), tsangibeilin B (2), endiandramide A (3), endiandric acid K (4), endiandric acid L (5), and endiandramide B (6). Also isolated were two new lignans, beilschminol A (7) and tsangin C (8), and six known compounds. The structures of 1-8 were determined by spectroscopic techniques. Compounds 3 and 6 exhibited potent iNOS inhibitory activity, with IC(50) values of 9.59 and 16.40 µM, respectively.

Sesquiterpene glycosides from Cosmospora joca.

Five novel sesquiterpene glycosides, namely, cosmosporasides A-E (1-5), were isolated from the ethyl acetate extract of the fermented broth of Cosmospora joca. The structures of 1-5 were elucidated on the basis of spectroscopic data analyses, monosaccharide composition analyses, and monosaccharide chirality analyses. The relative configuration of the sesquiterpene moiety of 3-5 was determined by J-based configuration analyses and supported by NOESY assignments. The inhibitory effects of 1-5 on the nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine macrophage RAW264.7 cells were evaluated; all except 3 inhibited NO production at 100 µM. 4 was the most potent, with an average maximum inhibition and a median inhibitory concentration value of 71.70 ± 1.23% and 65.98 ± 0.53 µM, respectively.

Secondary metabolites from the roots of Neolitsea daibuensis and their anti-inflammatory activity.

Bioassay-guided fractionation of the roots of Neolitsea daibuensis afforded three new ß-carboline alkaloids, daibucarbolines A-C (1-3), three new sesquiterpenoids, daibulactones A and B (4 and 5) and daibuoxide (6), and 20 known compounds. The structures of 1-6 were determined by spectroscopic analysis and single-crystal X-ray diffraction. Daibucarboline A (1), isolinderalactone (7), 7-O-methylnaringenin (8), and prunetin (9) exhibited moderate iNOS inhibitory activity, with IC50 values of 18.41, 0.30, 19.55, and 10.50 µM, respectively.

Involvement of nitric oxide in mesenteric vascular reactivity following intraperitoneal pancreatic juice in rats.

The purposes of this study were to examine the protein expressions of endothelial and inducible nitric oxide synthase (eNOS and iNOS) of the rat intestinal smooth muscle, and to elucidate the role of nitric oxide (NO) in the reactivity of the superior mesenteric artery (SMA) to vasoconstrictors following intraperitoneal (i.p.) injection of pancreatic juice. Immunohistochemistry was used to observe the protein expressions of eNOS and iNOS in the intestinal tissues 15 h after i.p. injection of pancreatic juice (1 ml/100 g body weight). To test the vascular reactiveness, SMA was isolated and perfused with Tyrode's solution at a constant flow rate of 5 ml/min. The changes in perfusion pressure as the measure of contractile responses to phenylephrine (PE) were monitored. I.P. injection of pancreatic juice induced increases of plasma levels of tumor necrosis factor α (TNFα) (P < 0.001; N = 7) and NO (P < 0.001; N = 7). Nω-nitro-L-arginine methyl ester (L-NAME) reduced the release of TNFα and NO. There were 8.3 ± 1.2-fold and 11.4 ± 2.8-fold increases in the protein expressions of eNOS and iNOS, respectively, in the intestinal tissue after pancreatic juice injection. PE (10⁻8 ~ 10⁻4 M) produced a dose-dependent vasoconstrictive effects on the SMA bed. Contractile responses to PE were attenuated in pancreatic juice-treated group. Addition of L-NAME (10⁻4 M) resulted in full recovery of the responses to phenylephrine in SMA bed, while aminoguanidine (AG, 10⁻4 M) caused only partial recovery. Our results indicate that i.p. injection of pancreatic juice results in a decrease in vascular reactivity of mesenteric vessels that is dependent on both eNOS and iNOS expressions in the intestinal vascular bed. Overproduction of NO elicits intestinal low vascular reactivity.