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Cardiac fibroblasts (CF) are mesenchymal-type cells responsible for maintaining the homeostasis of the heart's extracellular matrix (ECM). Their dysfunction leads to excessive secretion of ECM proteins, tissue stiffening, impaired nutrient and oxygen exchange, and electrical abnormalities in the heart. Additionally, CF act as sentinel cells in the cardiac tissue microenvironment, responding to various stimuli that may affect heart function. Deleterious stimuli induce an inflammatory response in CF, increasing the secretion of cytokines such as IL-1β and TNF-α and the expression of cell adhesion molecules like ICAM1 and VCAM1, initially promoting damage resolution by recruiting immune cells. However, constant harmful stimuli lead to a chronic inflammatory process and heart dysfunction. Therefore, it is necessary to study the mechanisms that govern CF inflammation. NFκB is a key regulator of the cardiac inflammatory process, making the search for mechanisms of NFκB regulation and CF inflammatory response crucial for developing new treatment options for cardiovascular diseases. SGK1, a serine-threonine protein kinase, is one of the regulators of NFκB and is involved in the fibrotic effects of angiotensin II and aldosterone, as well as in CF differentiation. However, its role in the CF inflammatory response is unknown. On the other hand, many bioactive natural products have demonstrated anti-inflammatory effects, but their role in CF inflammation is unknown. One such molecule is boldine, an alkaloid obtained from Boldo (Peumus boldus), a Chilean endemic tree with proven cytoprotective effects. However, its involvement in the regulation of SGK1 and CF inflammation is unknown. In this study, we evaluated the role of SGK1 and boldine in the inflammatory response in CF isolated from neonatal Sprague-Dawley rats. The involvement of SGK1 was analyzed using GSK650394, a specific SGK1 inhibitor. Our results demonstrate that SGK1 is crucial for LPS- and IFN-γ-induced inflammatory responses in CF (cytokine expression, cell adhesion molecule expression, and leukocyte adhesion). Furthermore, a conditioned medium (intracellular content of CF subject to freeze/thaw cycles) was used to simulate a sterile inflammation condition. The conditioned medium induced a potent inflammatory response in CF, which was completely prevented by the SGK1 inhibitor. Finally, our results indicate that boldine inhibits both SGK1 activation and the CF inflammatory response induced by LPS, IFN-γ, and CF-conditioned medium. Taken together, our results position SGK1 as an important regulator of the CF inflammatory response and boldine as a promising anti-inflammatory drug in the context of cardiovascular diseases. • Inflammatory stimuli increase SGK1 activity and expression in cardiac fibroblasts. • SGK1 is required for the inflammatory response of cardiac fibroblasts. • Boldine prevents SGK1 and NFκB activation induced by inflammatory stimuli. • Boldine prevents the inflammatory response of cardiac fibroblasts. [ABSTRACT FROM AUTHOR]

Boldine, a bioactive compound, has been reported to be neuroprotective, but its effect on learning and memory has not been explored. So, the present study was aimed to study the effect of boldine on the learning and memory of the Swiss albino male young and aged mice. Boldine (1.5, 3 and 6 mg/kg, po) and physostigmine salicylate (0.1 mg/kg, ip) were administered to separate groups of mice for 7 successive days. Morris water maze was utilized as a behavioural model to study the effect of drugs on learning and memory of mice. Boldine and physostigmine significantly improved learning and memory of young as well as aged mice, as indicated by decrease in escape latency time during training session and increase in time spent in target quadrant during retrieval session. No significant effect on locomotor activities of mice was observed due to drug treatments. Memory-enhancing activity of boldine (3 mg/kg) was found to be comparable to physostigmine. Boldine significantly reversed scopolamine-, sodium nitrite- and aging-induced amnesia in mice. Moreover, boldine attenuated oxidative stress, as shown by a significant decrease in brain malondialdehyde as well as brain nitrite levels and a significant increase in brain GSH level of young as well as aged mice. Brain acetylcholinesterase activity was also significantly inhibited by boldine in young as well as aged mice. In conclusion boldine administered for 7 successive days exhibited significant improvement of learning and memory of young and aged mice possibly through inhibition of brain acetylcholinesterase activity and alleviation of brain oxidative stress. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of boldine isolated from Litsea cubeba on collagen-induced arthritis (CIA) rats and explore the molecular mechanism predicted by network pharmacology. Material and methods CIA rats were orally administered with boldine. The bone destruction of paws was analyzed by histologic examination, tartrate-resistant acid phosphatase (TRACP) staining and micro-computed tomography. Prediction of signal pathway associated with boldine network molecules and CIA genes was applied by the network pharmacology analysis. The expressions of osteoprotegerin (OPG), receptor activator of nuclear factor-κB (RANK) and its ligand (RANKL) in the ankle were detected by immunohistochemistry. In vitro osteoclasts were cultured in the presence of variable doses of boldine and the RANK expressions were evaluated using Real-time polymerase chain reaction and western blot. Results Boldine reduced ankle swelling, alleviated pathological damage and significantly prevented bone destruction in CIA rats. Consistent with this, enzyme linked immunosorbent assay revealed boldine decreased serum TRACP5b levels and osteoclast number in the ankle region by TRACP staining from CIA rats. The network pharmacology analysis indicated that RANK signaling in osteoclasts was the most significant canonical pathway associated with boldine network molecules and CIA genes, which was verified by the increased expression of OPG, reduced expression of RANK, RANKL and RANKL/OPG in boldine-treated CIA rats. The in vitro study further confirmed that boldine inhibited osteoclastogenesis by inhibiting the RANKL/RANK signaling pathway. Conclusion Taken together, our study first indicates that boldine from Litsea cubeba suppresses osteoclastogenesis, improves bone destruction by down-regulating the OPG/RANKL/RANK signal pathway and may be a potential therapeutic agent for rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

A new green on-line method for Boldine determination (BOL) in herbal drugs and phytopharmaceuticals, using its native fluorescence in acid media (λ ex = 282 nm; λ em = 373 nm) has been developed. The presented methodology involves for the first time, a flow injection (FI) strategy using a mini-column of multiwalled carbon nanotubes as retention agent coupled with molecular fluorescence. Different parameters influence as sample pH and flow rate, eluent flow rate and composition; on BOL sensitivity and elution time was investigated by multifactorial techniques. Adequate dynamic calibration range (r 2 = 0.9993) was obtained over a concentration interval of 0.029–27.0 μg mL − 1 BOL. The limits of detection (LOD) and quantification (LOQ) were 0.008 and 0.029 μg mL − 1 , respectively. The average recoveries in explored samples ranged from 95% to 103%. Under optimized conditions, the throughput sample as high as 30 h − 1 was achieved with high repeatability performance (99%). The proposed development represents a useful and valuable tool emulating the analytical efficiency of the official methodologies for quality control of herbal and phytopharmaceutical drugs containing BOL. Moreover, this approach shows advantages respect to low cost, simplicity and environmental and analyst friendly. [ABSTRACT FROM AUTHOR]

Intravenous corticosteroids, methylprednisolone (MPL), which is one of the drugs that induce glomerular kidney diseases, when used for a long time at high dose by doctors to treat acute renal inflammation, promote the development of reactive oxygen species (ROS)-induced renal toxicity. This study investigated the role of boldine, a natural antioxidant with anti-apoptotic and anti-inflammatory properties, against MPL-induced renal toxicity in male Wistar rats. 120 rats were divided into eight equal groups as follows: G1 (control), G2, 3, and 4 (rats orally administered 5, 10, and 50 mg boldine/kg/day; respectively, for 28 days), G5 (rats intramuscularly injected with 100 mg MPL/kg only on the last three days), G6, 7, and 8 (rats administered boldine + MPL). After the last MPL injection, rats were sacrificed at intervals of 1, 24, and 48 h. There was a significant increase in body weight, blood glucose, and urea levels, as well as a decrease in albumin level in serum. Oxidative stress markers levels increased at all times, and gene expression of anti-oxidant enzymes increased at 24 h. According to immunohistochemistry, there was a considerable increase in P53 and TNF-α levels following MPL therapy. The cell death DNA assays revealed detectable necrosis and apoptosis, induced by MPL treatment. Oral administration of boldine has a modulatory protective, anti-oxidant, anti-apoptotic, and anti-inflammatory effect against free radicals. [ABSTRACT FROM AUTHOR]

In a preliminary screening study of natural alkaloids, boldine, an aporphine alkaloid, showed an interesting dose and time dependent anti-proliferative effect in several cancer cell lines. Cytotoxicity of boldine in human fibroblasts was considerably lower than the telomerase positive embryonic kidney HEK293 and breast cancer MCF-7 and MDA-MB-231 cells. Whether boldine can inhibit telomerase was investigated here using a modified quantitative real-time telomere repeat amplification protocol (q-TRAP). This test showed that boldine inhibits telomerase in cells treated with sub-cytotoxic concentrations. Telomerase inhibition occurs via down-regulation of hTERT, the catalytic subunit of the enzyme. Boldine changed the splicing variants of hTERT towards shorter non-functional transcripts as well. A direct interaction of boldine with the enzyme may also be involved, though thermal FRET method did not detect any substantial interaction between boldine and synthetic telomere sequences. This study advocates boldine as a valuable candidate for telomerase-targeted cancer care. This study suggests that derivatives of boldine could be potent anti-cancer drugs. [ABSTRACT FROM AUTHOR]

Prismatic silver nanoparticles (PNps) were used in the surface enhanced Raman scattering (SERS) study of the antioxidant alkaloid boldine (5,6,6a,7-tetrahydro-1,10-dimethoxy-6-methyl-4H-dibenzo[de,g]quinoline-2,9-diol). Prismatic and quasi-spherical (QsNps) silver nanoparticles were synthesized and characterized by UV-Vis spectra, topographic profile (AFM) and zeta potential measurements. Raman and infrared (IR) spectra of the boldine were registered. Theoretical model calculations of the boldine onto the Ag surface predict a nearly coplanar orientation of the benzo[de]quinoline moiety and non-bonded interactions (electrostatic). [ABSTRACT FROM AUTHOR]

Highlights: [•] P. boldus tea blunts iron induced oxidative stress in liver mitochondria. [•] Boldine had a modest antioxidant effect in isolated mitochondria. [•] Boldine was a better scavenger of DPPH radical than P. boldus tea. [•] P. boldus and boldine can have synergic antioxidant properties. [•] P. boldus and boldine can have synergic antioxidant properties as well as synergic effects in hepatoprotection. [ABSTRACT FROM AUTHOR]

Highlights: [•] Major boldine metabolites were identified in rats for the first time. [•] A universal method for assay in plasma, bile and urine was developed. [•] Fluorescence and mass spectrometric detection were used. [•] Validation demonstrated the high precision and accuracy of the method. [•] Extended pharmacokinetic data for boldine were obtained. [ABSTRACT FROM AUTHOR]

Abstract: Increased oxidative stress is involved in the pathogenesis and progression of diabetes. Antioxidants are therapeutically beneficial for oxidative stress-associated diseases. Boldine ([s]-2,9-dihydroxy-1,10-dimethoxyaporphine) is a major alkaloid present in the leaves and bark of the boldo tree (Peumus boldus Molina), with known an antioxidant activity. This study examined the protective effects of boldine against high glucose-induced oxidative stress in rat aortic endothelial cells (RAEC) and its mechanisms of vasoprotection related to diabetic endothelial dysfunction. In RAEC exposed to high glucose (30mM) for 48h, pre-treatment with boldine reduced the elevated ROS and nitrotyrosine formation, and preserved nitric oxide (NO) production. Pre-incubation with β-NAPDH reduced the acetylcholine-induced endothelium-dependent relaxation; this attenuation was reversed by boldine. Compared with control, endothelium-dependent relaxation in the aortas of streptozotocin (STZ)-treated diabetic rats was significantly improved by both acute (1μM, 30min) and chronic (20mg/kg/daily, i.p., 7 days) treatment with boldine. Intracellular superoxide and peroxynitrite formation measured by DHE fluorescence or chemiluminescence assay were higher in sections of aortic rings from diabetic rats compared with control. Chronic boldine treatment normalized ROS over-production in the diabetic group and this correlated with reduction of NAD(P)H oxidase subunits, NOX2 and p47phox. The present study shows that boldine reversed the increased ROS formation in high glucose-treated endothelial cells and restored endothelial function in STZ-induced diabetes by inhibiting oxidative stress and thus increasing NO bioavailability. [Copyright &y& Elsevier]

Abstract: Boldine is one of the most potent natural antioxidants and displays some important pharmacological activities, such as cytoprotective and anti-inflammatory activities. Based on its antioxidant properties, we studied the effects of boldine on l-DOPA oxidation by evaluating the inhibitory kinetics and a computational simulation between boldine and tyrosinase. Boldine reversibly inhibited tyrosinase from mushroom (Agaricus bisporus) in a mixed-type manner, with a K i =7.203±0.933mM. To gain insight into the inactivation process, we computed the kinetics via time-interval measurements and continuous substrate reactions. The results indicated that the inactivation induced by boldine was a first-order reaction with biphasic processes and that the substrate can promote the inactivation process. To gain further insight, we performed computational docking and molecular dynamics simulations, and the results showed that boldine can interact with several residues near the tyrosinase active site. Our study provides insight into the inhibition of tyrosinase in response to alkaloids. Based on its tyrosinase-inhibiting effect and low toxicity, boldine is a potential natural anti-pigmentation agent. [Copyright &y& Elsevier]

Abstract: A novel oxaliplatin analogue, [Pt((1R,2R)-diaminocyclohexane)(3-carboxypredicentrinato)], boldiplatin, has been synthesized by the coordination of the boldine derivative 3-carboxypredicentrinate to the corresponding platinum(II) moiety in 5.8% overall yield. The complex was fully characterized and biologically evaluated in vitro. Boldiplatin was compared with its parent drug oxaliplatin, showing equal activity over four human tumor cell lines (MCF-7, MDA-MB-231, PC-3 and HT-29) and a tenfold decrease in toxicity over a non-tumor cell line (DHF). This selectivity makes boldiplatin a good candidate for further evaluations to assess its potential as antitumor drug. [Copyright &y& Elsevier]

Abstract: Boldo (Peumus boldus Mol.), a Chilean tree traditionally employed in folk medicine and recognized as a herbal remedy in a number of pharmacopoeias, mainly for the treatment of liver ailment, has recently been the subject of increasing attention. Boldine, in particular, the major and most characteristic alkaloid constituent of this plant species, now emerges as its most interesting active principle from the pharmacological viewpoint. In the present work the structural and spectral characteristics of boldine have been studied by methods of infrared, Raman spectroscopy and quantum chemistry. Electrostatic potential surface, optimized geometry, harmonic vibrational frequencies, infrared intensities and activities of Raman scattering were calculated by ab initio Hartree-Fock (HF) and density functional theory (DFT) employing B3LYP with complete relaxation in the potential energy surface using 6-311G(d,p) basis set. A complete vibrational assignment is provided for the observed Raman and infrared spectra of boldine molecule. [Copyright &y& Elsevier]

Abstract: Boldine is one of the most potent natural antioxidants and displays some important pharmacological activities, such as cytoprotective and anti-inflammatory activities, which may arise from its free radical scavenging properties. Given that the pathogenesis of brain ischemia/reperfusion has been associated with an excessive generation of oxygen free radicals, the aim of this study was to evaluate the neuroproperties of boldine using hippocampal slices from Wistar rats exposed to oxygen and glucose deprivation (OGD), followed by reoxygenation, to mimic an ischemic condition. The OGD ischemic condition significantly impaired cellular viability, increased lactate dehydrogenase (LDH) leakage and increased free radical generation. In non-OGD slices, incubation with 100μM boldine significantly increased LDH released into incubation media and decreased mitochondrial activity, suggesting an increase of tissue damage caused by boldine. However, slices incubated with 10μM boldine during and after OGD exposure had significantly increased cellular viability with no effect on cell damage. Total reactive antioxidant potential (TRAP) levels measured for this alkaloid showed an antioxidant potential three times higher than Trolox, which acts as a peroxyl radical scavenger. Moreover, boldine prevented the increase in lipoperoxidation levels induced by ischemia, but higher concentrations potentiated this parameter. These results confirm the potent antioxidant properties of this alkaloid, and add evidence to support the need for further investigations in order to confirm the potential pro-oxidant effects of boldine at higher doses. [Copyright &y& Elsevier]

Abstract: The bubble-points pressures of solute(s)+ethanol+water+CO2 mixtures were determined visually using a synthetic method in an experimental apparatus that included a variable-volume equilibrium cell. Tested solutes included boldo leaf tincture, a boldine+catechin mixture, pure boldine, and pure catechin. Uncertainties in bubble-point pressures were estimated to be <5%, based on comparisons with literature values and replicate measurements. The largest effect we observed was an average increase of 205% in the bubble-point pressure when decreasing the ethanol-to-water ratio from 63:37 to 37:63 (w/w). The bubble-point pressure increased 11% when increasing the temperature from 313 to 343K, and decreased 8.2% when increasing the concentration of solids from 400 to 1500ppm. The bubble-point pressure was higher for boldo leaf tincture than for a boldine+catechin mixture having the same boldine-to-catechin weight ratio, but this was partially due to a lower content of solids in the tincture. On the other hand, bubble-point pressures of the boldine+catechin mixture were marginally (0.33%) higher than the weighed average of the bubble-point pressures for pure boldine and pure catechin. [Copyright &y& Elsevier]

Abstract: Densities of boldine+alcohol binary mixtures were measured over the whole accessible range of boldine compositions at temperatures from 283.15 to 333.15K using an Anton-Paar digital vibrating glass tube densimeter. The binary systems studied include, as a solvent, seven normal alcohols from n-C1 to n-C6, n-C8, and isopropanol. The density of these systems has been found an increasing function of the boldine composition. A new methodology based on density data of solutions of solid solutes with normal alcohols is described in order to determine solid molar volume of pure solutes. This methodology was validated with pure solid naphthalene molar volumes data at 298.15K, with an average uncertainty of 6%. [Copyright &y& Elsevier]

Abstract: The increasing recognition of the participation of free radical-mediated oxidative events in the initiation and/or progression of cardiovascular, tumoural, inflammatory and neurodegenerative disorders, has given rise to the search for new antioxidant molecules. An important source of such molecules has been plants for which there is an ethno-cultural base for health promotion. An important example of this is boldo (Peumus boldus Mol.), a chilean tree whose leaves have been traditionally employed in folk medicine and is now widely recognized as a herbal remedy by a number of pharmacopoeias. Boldo leaves are rich in several aporphine-like alkaloids, of which boldine is the most abundant one. Research conducted during the early 1990s led to the discovery that boldine is one of the most potent natural antioxidants. Prompted by the latter, a large and increasing number of studies emerged, which have focused on characterizing some of the pharmacological properties that may arise from the free radical-scavenging properties of boldine. The present review attempts to exhaustively cover and discuss such studies, placing particular attention on research conducted during the last decade. Mechanistic aspects and structure–activity data are discussed. The review encompasses pharmacological actions, which arise from its antioxidant properties (e.g., cyto-protective, anti-tumour promoting, anti-inflammatory, anti-diabetic and anti-atherogenic actions), as well as those that do not seem to be associated with such activity (e.g., vasorelaxing, anti-trypanocidal, immuno- and neuro-modulator, cholagogic and/or choleretic actions). Based on the pharmacological and toxicological data now available, further research needs and recommendations are suggested to define the actual potential of boldine for its use in humans. [Copyright &y& Elsevier]

Abstract: This work contributes to the development of an enrichment process for antioxidant compounds in aqueous alcoholic extracts of boldo (Peumus boldus M.) leaves by using high-pressure CO2 as the solvent. Specifically we measured the high-pressure solubility (y 2, molar fraction) of a selected bioactive compound in boldo leaves (boldine) in CO2 as a function of system temperature (298K≤ T ≤333K) and pressure (8MPa≤ P ≤40MPa). Experimental data was correlated by using a density-based model which is valid for solvent densities >607kg/m3. Predicted solubility values are low (4×10−7 ≤ y 2 ≤6×10−5) but comparable with those of nitrogen-containing organic compounds with similar molecular weight (327.4Da) and solubility parameter (28.3MPa0.5 at 313K) as boldine. [Copyright &y& Elsevier]

Abstract: Boldine hydrochloride was more photounstable than boldine after irradiation with UVB (λ =300 nm). However, photoconsumption quantum yields, for glaucine hydrochloride (6.5×10−2) and boldine hydrochloride (6.7×10−2) in air, were quite similar. The photolysis was oxygen dependent in both cases, and the effect over the kinetics after the addition of 2,2,6,6-tetramethyl-1-piperidinyloxy suggested free radicals participation. The fact that the antioxidative capacity of boldine and boldine hydrochloride did not change during the photolysis, suggests that the phenolic structure remains unchanged in the photoproducts, corroborated with the photoproducts analysis. The photoprotection capacity was evaluated before and after irradiation. Results indicate that the values before irradiation are similar for all three compounds, only glaucine increasing its capacity with length of irradiation time. [Copyright &y& Elsevier]

Abstract: High-activity fractions in boldo leaves were extracted with supercritical CO2 (SC-CO2) and hot pressurized water (HPW). Total yield after 3 h of extraction (0.6–3.5%) in low-pressure SC-CO2 experiments increased with process pressure (60–150 bar) and decreased with temperature (30–60 °C), as expected. The extract obtained with SC-CO2 at 50 °C and 90 bar contained approximately 50% of essential oil components. In higher pressure experiments with solvent mixtures, the yield increased with pressure (300–450 bar) and modifier concentration (2–10% ethanol), ranging 0.14–1.95 ppm for the alkaloid boldine and 1.8–4.8% for total solids following 1.5 h treatment at 50 °C. Boldine recovery was solubility-controlled, reaching 7.4 ppm after 7-h extraction at 450 bar and 50 °C using an ethanol–SC-CO2 mixture (5% co-solvent). Boldine solubility and yield decreased when using pure CO2 at higher pressure (600 bar, 50 °C). The extract yield after 3 h batch-wise HPW extraction increased from 36.9% at 100 °C to 53.2% at 125 °C, and then decreased as temperature was increased to 175 °C. Boldine yield decreased from 26.8 ppm at 100 °C to 0.7 ppm at 125 °C, and was negligible at ⩾150 °C. The essential oil yield increased to a maximum at 110 °C and was negligible at ⩾150 °C also. The ranking of antioxidant potency of various extracts was as follows: HPW at 110 °C>methanol (soxhlet extraction)≫high-pressure SC-CO2 with or without polar co-solvent>low-pressure SC-CO2. [Copyright &y& Elsevier]

Boldo (Peumus boldus M.) is a native plant from Chile that has been used is traditional medicine to treat digestive and/or hepatobiliary disorders. An attempt was made in this work to extract antioxidant compounds from boldo using conventional solvents and supercritical carbon dioxide (SCCO2). Yield of soluble solids (SS), boldine, and compounds with antioxidant activity varied depending on part plant, solvent and extraction conditions. Following 24 h extraction, the highest yield was 33.4% (w/w, dry basis) of SS with 70:30 ethanol/water (v/v) mixture at 70 °C. Yield of alcoholic extractions increased as the temperature was raised from 20 to 70 °C, but the total antioxidant activity (free radical DPPH method) was maximal in boldo leaf extracts with aqueous ethanol at 50 °C (1648 TEAC/g dry leaf). Boldine concentration was maximal (12%) in boldo bark extracted with acidulated water, and decreased with extraction time when methanol or ethanol/water mixtures were used. No boldine was detected in boldo leaf extracts. The contribution of boldine to the antioxidant activity of boldo extracts was low, specially when using aqueous ethanol as solvent, and/or boldo leaf instead of boldo bark as substrate. Yield of SCCO2 extraction was ≈3% SS. Only non-polar compounds with limited antioxidant activity (0.08 TEAC/g extract) were extracted by SCCO2. [Copyright &y& Elsevier]

In this work we present spectroscopic study of Boldine (aporphine alkaloid) that possesses important biological activities, in particular, in interaction with the promastigotes of Leishmania mexicana. The results show the applicability of autofluorescence of this drug to determinate the possible mechanism of its biological action. The blue shift and hyperchromic effect in the emission spectrum of the drug in interaction with the parasite cells indicate an energy transference process between them. The morphological change of cell shape of the promastigotes treated with the drug is observed using confocal microscopy. This morphological cell-shape transformation evidences an important interaction between the drug studied and some protein of the parasite cell. Here we describe for the first time the fluorescence properties of the Boldine in the promastigotes of L. mexicana. [Copyright &y& Elsevier]

Boldine ([S]-2,9-dihydroxy-1,10-dimethoxyaporphine) has been shown to exert antioxidant and anti-inflammatory effects. The present study elucidated the protective effect of boldine on catecholamine-induced membrane permeability transition in brain mitochondria and viability loss in PC12 cells. Dopamine (200 μM) and 6-hydroxydopamine (6-OHDA, 100 μM) attenuated Ca2+ and succinate-induced mitochondrial swelling and membrane potential formation. Boldine (10–100 μM) and 10 μg/mL of superoxide dismutase (SOD) or catalase reduced the effect of catecholamine oxidation on brain mitochondria. Boldine, SOD, and catalase decreased catecholamine-induced mitochondrial cytochrome c release. Antioxidant enzymes attenuated the depressant effect of catecholamines on mitochondrial electron flow, whereas boldine did not reduce it. Boldine inhibited the catecholamine-induced decrease in thioredoxin reductase activity and the increase in thiol oxidation in mitochondria. It also showed a scavenging action on hydrogen peroxide and hydroxyl radicals and decreased the formation of melanin from dopamine. Boldine and antioxidant enzymes decreased the dopamine-induced cell death, including apoptosis, in PC12 cells. The results suggest that boldine may attenuate the catecholamine oxidation-induced brain mitochondrial dysfunction and decrease the dopamine-induced death of PC12 cells through a scavenging action on reactive oxygen species and inhibition of melanin formation and thiol oxidation. [Copyright &y& Elsevier]

Boldine is the main alkaloid of Peumus boldus Molina, widely used in the traditional medicine for the treatment of digestive disorders. It is a compound with excellent antioxidant and anti-inflammatory properties already described. Despite the widespread use of P. boldus for digestive disorders treatment, the gastroprotective effect of Boldine remains unknown. Considering the need for new approaches to treat gastric ulcers with fewer side effects than current therapy, this study aimed to investigate the gastroprotective effect of Boldine in mice, as well as the mechanisms underlying this effect. The gastroprotective effect of Boldine was evaluated on gastric ulcer induced by 60% ethanol/0.3 M HCl or indomethacin (100 mg/kg) in mice. Histological analysis and the mucin-like glycoprotein content were evaluated in ethanol-ulcerated tissue, as well as, oxidative stress and inflammatory parameters. The mechanisms involved in the effect of Boldine were evaluated by pretreating mice with NEM (a sulfhydryl group chelator, 10 mg/kg, i.p.), l -NAME (a non-selective nitric oxide synthase inhibitor, 70 mg/kg, i.p.), yohimbine (an alpha-adrenergic receptor antagonist, 2 mg/kg, i.p.) and indomethacin (a cyclooxygenase inhibitor, 10 mg/kg, i.p.). In addition, the in vitro effect of Boldine on H+/K+-ATPase activity was determined. Boldine was able to protect gastric mucosa against the damage induced by ethanol/HCl and indomethacin, as evidenced by reduced lesion area and histological analysis. Moreover, the alkaloid reduced oxidative stress and inflammatory mediators in ethanol-ulcerated tissue, beyond has increased mucin-like glycoprotein amount. Finally, Boldine effect is dependent on non-protein sulfhydryl groups and prostanoids but does not involve the inhibition of H+/K + -ATPase activity, being a promising natural resource for gastric ulcer treatment. Image 1 • Boldine protects gastric mucosa against damage induced by ethanol and indomethacin. • Boldine reduces oxidative stress and inflammatory mediators. • Boldine increases mucin-like glycoprotein in the gastric mucosa. • Boldine's effect is dependent on non-protein sulfhydryl groups and prostanoids. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Bladder cancer is one of the most prevalent genitourinary malignancies. Despite active chemotherapy regimens, patients with bladder cancer suffer from a high rate of tumor recurrence. Thus, new approaches and agents to improve quality of life and survival still need to be developed. The objective of the present study was to evaluate the effect and underlying mechanisms of boldine, an aporphine alkaloid of Peumus boldus, on bladder cancer proliferation and cell death. Methods: Sulforhodamine B assay, Tetrazolium reduction assay, Flow Cytometry Analysis, Ecto-5’-nucleotidase activity and Western blot assay were performed. Results: The results showed that boldine was able to reduce cell viability and cell proliferation in T24 cells. In addition, boldine arrests the cell cycle at G2/M-phase and cause cell death by apoptosis. Boldine-induced inhibition of cell growth and cell cycle arrest appears to be linked to inactivation of extracellular signal–regulated kinase protein (ERK). Additionally, the efficacy of boldine in apoptosis-induced in T24 cells is correlated with modulation of AKT (inactivation) and glycogen synthase kinase-3β (GSK-3β) (activation) proteins. Conclusions: The present findings may, in part, explain the therapeutic effects of boldine for treatment of urinary bladder cancer. [Copyright &y& Elsevier]