Involvement of the AKT Pathway in Resistance to Erlotinib and Cabozantinib in Triple-Negative Breast Cancer Cell Lines

Resistance to protein tyrosine kinase inhibitors (TKIs) presents a significant challenge in therapeutic target development for cancers such as triple-negative breast cancer (TNBC), where conventional therapies are ineffective at combatting systemic disease. Due to increased expression, the receptor tyrosine kinases EGFR (epidermal growth factor receptor) and c-Met are potential targets for treatment. However, targeted anti-EGFR and anti-c-Met therapies have faced mixed results in clinical trials due to acquired resistance. We hypothesize that adaptive responses in regulatory kinase networks within the EGFR and c-Met signaling axes contribute to the development of acquired erlotinib and cabozantinib resistance. To test this, we developed two separate models for cabozantinib and erlotinib resistance using the MDA-MB-231 and MDA-MB-468 cell lines, respectively. We observed that erlotinib- or cabozantinib-resistant cell lines demonstrate enhanced cell proliferation, migration, invasion, and activation of EGFR or c-Met downstream signaling (respectively). Using a SILAC (Stable Isotope Labeling of Amino acids in Cell Culture)-labeled quantitative mass spectrometry proteomics approach, we assessed the effects of erlotinib or cabozantinib resistance on the phosphoproteome, proteome, and kinome. Using this integrated proteomics approach, we identified several potential kinase mediators of cabozantinib resistance and confirmed the contribution of AKT1 to erlotinib resistance in TNBC-resistant cell lines.

Chemical Genetic Validation of CSNK2 Substrates Using an Inhibitor-Resistant Mutant in Combination with Triple SILAC Quantitative Phosphoproteomics

Casein Kinase 2 (CSNK2) is an extremely pleiotropic, ubiquitously expressed protein kinase involved in the regulation of numerous key biological processes. Mapping the CSNK2-dependent phosphoproteome is necessary for better characterization of its fundamental role in cellular signalling. While ATP-competitive inhibitors have enabled the identification of many putative kinase substrates, compounds targeting the highly conserved ATP-binding pocket often exhibit off-target effects limiting their utility for definitive kinase-substrate assignment. To overcome this limitation, we devised a strategy combining chemical genetics and quantitative phosphoproteomics to identify and validate CSNK2 substrates. We engineered U2OS cells expressing exogenous wild type CSNK2A1 (WT) or a triple mutant (TM, V66A/H160D/I174A) with substitutions at residues important for inhibitor binding. These cells were treated with CX-4945, a clinical-stage inhibitor of CSNK2, and analyzed using large-scale triple SILAC (Stable Isotope Labelling of Amino Acids in Cell Culture) quantitative phosphoproteomics. In contrast to wild-type CSNK2A1, CSNK2A1-TM retained activity in the presence of CX-4945 enabling identification and validation of several CSNK2 substrates on the basis of their increased phosphorylation in cells expressing CSNK2A1-TM. Based on high conservation within the kinase family, we expect that this strategy can be broadly adapted for identification of other kinase-substrate relationships.

Pannexin 1 mutation found in melanoma tumor reduces phosphorylation, glycosylation, and trafficking of the channel-forming protein

Pannexin 1 (PANX1) is a glycoprotein that forms large pore channels capable of passing ions and metabolites such as ATP for cellular communication. PANX1 has been implicated in many diseases including breast cancer and melanoma, where inhibition or deletion of PANX1 reduced the tumorigenic and metastatic properties of the cancer cells. We interrogated the effect of single amino acid changes in various PANX1 domains using naturally occurring variants reported in cancer patient tumors. We found that a previously reported variant (Q5H) is present in cancer cells, but was not different from the wild type (Q5) in glycosylation, trafficking, or channel function and did not affect cellular properties. We discovered that the Q5H variant is in fact the highly conserved ancestral allele of PANX1 with 89% of humans carrying at least one Q5H allele. Another mutated form Y150F, found in a melanoma patient tumor, prevented phosphorylation at Y150 as well as complex N-glycosylation while increasing intracellular localization. Sarcoma (SRC) is the predicted kinase to phosphorylate the Y150 residue, and its phosphorylation is not likely to be constitutive, but rather dynamically regulated. The Y150 phosphorylation site is the first one reported to play a role in regulating posttranslational modifications and trafficking of PANX1, with potential consequences on its large-pore channel structure and function in melanoma cells.

Regional Lipid Expression Abnormalities Identified Using MALDI IMS Correspond to MRI-Defined White Matter Hyperintensities within Post-mortem Human Brain Tissues

Periventricular white matter hyperintensities (pvWMHs) are a neurological feature detected with magnetic resonance imaging that are clinically associated with an increased risk of stroke and dementia. pvWMHs represent white matter lesions characterized by regions of myelin and axon rarefaction and as such likely involve changes in lipid composition; however, these alterations remain unknown. Lipids are critical in determining cell function and survival. Perturbations in lipid expression have previously been associated with neurological disorders. Matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry (IMS) is an emerging technique for untargeted, high-throughput investigation of lipid expression and spatial distribution in situ; however, the use of MALDI IMS has been previously been limited by the need for non-embedded, non-fixed, fresh-frozen samples. In the current study, we demonstrate the novel use of MALDI IMS to distinguish regional lipid abnormalities that correlate with magnetic resonance imaging (MRI) defined pvWMHs within ammonium formate washed, formalin-fixed human archival samples. MALDI IMS scans were conducted in positive or negative ion detection mode on tissues sublimated with 2,5-dihydroxybenzoic acid or 1,5-diaminonaphthalene matrices, respectively. Using a broad, untargeted approach to lipid analysis, we consistently detected 116 lipid ion species in 21 tissue blocks from 11 different post-mortem formalin-fixed human brains. Comparing the monoisotopic mass peaks of these lipid ions elucidated significant differences in lipid expression between pvWMHs and NAWM for 31 lipid ion species. Expanding our understanding of alterations in lipid composition will provide greater knowledge of molecular mechanisms underpinning ischemic white matter lesions and provides the potential for novel therapeutic interventions targeting lipid composition abnormalities.

Proteomic Analyses Detect Higher Expression of C-Type Lectins in Imidacloprid-Resistant Colorado Potato Beetle Leptinotarsa decemlineata Say

Simple Summary

Surveillance and determining the mechanisms of pesticide resistance are key components of resistance management. Mechanisms can be investigated using biochemical, genomic, proteomic and other modern analytical techniques. In the present study, proteomic analyses of Colorado potato beetle (CPB), one of the most adaptable insect pests to both plant toxins and synthetic insecticides, were applied to identify protein differences in insecticide-susceptible and resistant strains. Proteins identified in abdominal and midgut tissues based on separating by 2-dimensional (2-D) gels and mass spectrometry were associated with insect innate immunity. A database search found that the highest match was a C-type lectin (CTL), which is a component in the insect’s innate immune system. The 2-D gel spot identified as a CTL was greater in the insecticide-resistant CPB strain, but the CTL spot size was increased by exposure to imidacloprid in the susceptible strain. This is a novel finding, which suggests that CTLs and insect immunity may respond to certain toxins as well as to pathogens. There may also be a potential application for pest management if insect immunity is targeted.

Abstract

The Colorado potato beetle (CPB) is one of the most adaptable insect pests to both plant toxins and synthetic insecticides. Resistance in CPB is reported for over 50 classes of insecticides, and mechanisms of insecticide-resistance include enhanced detoxification enzymes, ABC transporters and target site mutations. Adaptation to insecticides is also associated with changes in behaviour, energy metabolism and other physiological processes seemingly unrelated to resistance but partially explained through genomic analyses. In the present study, in place of genomics, we applied 2-dimensional (2-D) gel and mass spectrometry to investigate protein differences in abdominal and midgut tissue of insecticide-susceptible (S) and -resistant (R) CPB. The proteomic analyses measured constitutive differences in several proteins, but the highest match was identified as a C-type lectin (CTL), a component of innate immunity in insects. The constitutive expression of the CTL was greater in the multi-resistant (LI) strain, and the same spot was measured in both midgut and abdominal tissue. Exposure to the neonicotinoid insecticide, imidacloprid, increased the CTL spot found in the midgut but not in the abdominal tissue of the laboratory (Lab) strain. No increase in protein levels in the midgut tissue was observed in the LI or a field strain (NB) tolerant to neonicotinoids. With the exception of biopesticides, such as Bacillus thuringiensis (Bt), no previous studies have documented differences in the immune response by CTLs in insects exposed to synthetic insecticides or the fitness costs associated with expression levels of immune-related genes in insecticide-resistant strains. This study demonstrates again how CPB has been successful at adapting to insecticides, plant defenses as well as pathogens.

Matrix-assisted laser desorption/ionization time-of-flight/time-of-flight tandem mass spectrometry (negative ion mode) of French Oak lignin: A novel series of lignin and tricin derivatives attached to carbohydrate and shikimic acid moieties

RATIONALE

We report the top-down lignomic analysis of the virgin released lignin (VRL) small oligomers obtained from French Oak wood.

METHODS

We have used MALDI-TOF-MS in the negative ion mode for the analysis of the complex mixture of lignin oligomers extracted from French Oak wood. High-energy CID-TOF/TOF-MS/MS analyses were used to support the postulated precursor ion structures.

RESULTS

Twenty compounds were identified using MALDI-TOF-MS/MS of the VRL extracted from French Oak wood: seven tricin derivatives and/or flavonoids, three syringylglycerol derivatives, two syringol derivatives, two flavonolignin derivatives, and six miscellaneous compounds: luteoferol, lariciresinol isomer, 5-hydroxy guaiacyl derivative, syringyl -C₁₀ H₁₀ O₂ dimer, trihydroxy benzaldehyde derivative, and aryl tetralin lignan derivative. Most of the identified compounds were in the form of carbohydrate and/or shikimic acid complexes.

CONCLUSIONS

The analysis of this complex mixture led to the identification of a series of lignin dimers, novel lignin-carbohydrate complexes (LCC), and unique tricin derivatives linked to different types of carbohydrates and shikimic acid moieties. This finding supports the presence of lignin-carbohydrate complexes in the isolated VRL. These analyses also showed that French Oak lignin is abundant in syringol moieties present in the lignin syringyl units or tricin derivatives. Moreover, the identification of some lignin-carbohydrate and/or flavonoid-shikimic acid complexes could provide new insight into the relationship between the biosynthesis of lignin and tricin.

Demystifying and unravelling the molecular structure of the biopolymer sporopollenin

RATIONALE

We report the unsolved molecular structure of the complex biopolymer sporopollenin exine extracted from Lycopodium clavatum pollen grains.

METHODS

TOF-SIMS and CID-MS/MS, MALDI-TOF-MS and CID-TOF/TOF-MS/MS were used for the analysis of this complex biopolymer sporopollenin exine extracted from Lycopodium clavatum pollen grains. Solid-state ¹ H- and ¹³ C-NMR, 2D ¹ H-¹ H NOESY, Rotor-synchronized ¹³ C{¹ H} HSQC, and ¹³ C{¹ H} multi CP-MAS NMR experiments were used to confirm the structural assigments revealed by MS and MS/MS studies. Finally, high-resolution XPS was used to check for the presence of aromatic components in sporopollenin.

RESULTS

The combined MS and NMR analyses showed that sporopollenin contained poly(hydroxy acid) dendrimer-like networks with glycerol as a core unit, which accounted for the sporopollenin empirical formula. In addition, these analyses showed that the hydroxy acid monomers forming this network contained a β-diketone moiety. Moreover, MALDI-TOF-MS and MS/MS allowed us to identify a unique macrocyclic oligomeric unit composed of polyhydroxylated tetraketide-like monomers. Lastly, high-resolution X-ray photoelectron spectroscopy (HR-XPS) showed the absence of aromaticity in sporopollenin.

CONCLUSIONS

We report for the first time the two main building units that form the Lycopodium clavatum sporopollenin exine. The first building unit is a macrocyclic oligomer and/or polymer composed of polyhydroxylated tetraketide-like monomeric units, which represents the main rigid backbone of the sporopollenin biopolymer. The second building unit is the poly(hydroxy acid) network in which the hydroxyl end groups can be covalently attached by ether links to the hydroxylated macrocyclic backbone to form the sporopollenin biopolymer, a spherical dendrimer. Such spherical dendrimers are a typical type of microcapsule that have been used for drug delivery applications. Finally, HR-XPS indicated the total absence of aromaticity in the sporopollenin exine.

Membrane-lipid homeostasis in a prodromal rat model of Alzheimer's disease: Characteristic profiles in ganglioside distributions during aging detected using MALDI imaging mass spectrometry

BACKGROUND

Accumulation of simple gangliosides GM2 and GM3, and gangliosides with longer long-chain bases (d20:1) have been linked to toxicity and the pathogenesis of Alzheimer's disease (AD). Conversely, complex gangliosides, such as GM1, have been shown to be neuroprotective. Recent evidence using matrix-assisted laser desorption ionization imaging mass spectrometry (MALDI-IMS) has demonstrated that a-series gangliosides are differentially altered during normal aging, yet it remains unclear how simple species are shifting relative to complex gangliosides in the prodromal stages of AD.

METHODS

Ganglioside profiles in wild-type (Wt) and transgenic APP21 Fischer rats were detected and quantified using MALDI-IMS at P0 (birth), 3, 12, and 20 months of age and each species quantified to allow for individual species comparisons.

RESULTS

Tg APP21 rats were found to have a decreased level of complex gangliosides in a number of brain regions as compared to Wt rats and showed higher levels of simple gangliosides. A unique pattern of expression was observed in the white matter as compared to gray matter regions, with an age-dependent decrease in GD1 d18:1 species observed and significantly elevated levels of GM3 in Tg APP21 rats.

CONCLUSIONS

These results are indicative of a pathological shift in ganglioside homeostasis during aging that is exacerbated in Tg APP21 rats.

GENERAL SIGNIFICANCE

Ganglioside dysregulation may occur in the prodromal stages of neurodegenerative diseases like AD.

1,6-Diphenyl-1,3,5-hexatriene (DPH) as a Novel Matrix for MALDI MS Imaging of Fatty Acids, Phospholipids, and Sulfatides in Brain Tissues

1,6-Diphenyl-1,3,5-hexatriene (DPH) is a commonly used fluorescence probe for studying cell membrane-lipids due to its affinity toward the acyl chains in the phospholipid bilayers. In this work, we investigated its use in matrix-assisted laser desorption/ionization (MALDI) as a new matrix for mass spectrometry imaging (MSI) of mouse and rat brain tissue. DPH exhibits very minimal matrix-induced background signals for the analysis of small molecules (below m/z of 1000). In the negative ion mode, DPH permits the highly sensitive detection of small fatty acids (m/z 200-350) as well as a variety of large lipids up to m/z of 1000, including lyso-phospholipid, phosphatidic acid (PA), phosphoethanolamine (PE), phosphatidylserine (PS), phosphatidylglycerol (PG), phosphatidylinositol (PI), and sulfatides (ST). The analytes were mostly detected as the deprotonated ion [M - H]^-. Our results also demonstrate that sublimated DPH is stable for at least 24 h under the vacuum of our MALDI mass spectrometer. The ability to apply DPH via sublimation coupled with its low volatility allows us to perform tissue imaging of the above analytes at high spatial resolution. The degree of lipid fragmentation was determined experimentally at varying laser intensities. The results illustrated that the use of relatively low laser energy is important to minimize the artificially generated fatty acid signals. On the other hand, the lipid fragmentation obtained at higher laser energies provided tandem MS information useful for lipid structure elucidation.

Increased Expression of Simple Ganglioside Species GM2 and GM3 Detected by MALDI Imaging Mass Spectrometry in a Combined Rat Model of Aβ Toxicity and Stroke

The aging brain is often characterized by the presence of multiple comorbidities resulting in synergistic damaging effects in the brain as demonstrated through the interaction of Alzheimer's disease (AD) and stroke. Gangliosides, a family of membrane lipids enriched in the central nervous system, may have a mechanistic role in mediating the brain's response to injury as their expression is altered in a number of disease and injury states. Matrix-Assisted Laser Desorption Ionization (MALDI) Imaging Mass Spectrometry (IMS) was used to study the expression of A-series ganglioside species GD1a, GM1, GM2, and GM3 to determine alteration of their expression profiles in the presence of beta-amyloid (Aβ) toxicity in addition to ischemic injury. To model a stroke, rats received a unilateral striatal injection of endothelin-1 (ET-1) (stroke alone group). To model Aβ toxicity, rats received intracerebralventricular (i.c.v.) injections of the toxic 25-35 fragment of the Aβ peptide (Aβ alone group). To model the combination of Aβ toxicity with stroke, rats received both the unilateral ET-1 injection and the bilateral icv injections of Aβ25-35 (combined Aβ/ET-1 group). By 3 d, a significant increase in the simple ganglioside species GM2 was observed in the ischemic brain region of rats who received a stroke (ET-1), with or without Aβ. By 21 d, GM2 levels only remained elevated in the combined Aβ/ET-1 group. GM3 levels however demonstrated a different pattern of expression. By 3 d GM3 was elevated in the ischemic brain region only in the combined Aβ/ET-1 group. By 21 d, GM3 was elevated in the ischemic brain region in both stroke alone and Aβ/ET-1 groups. Overall, results indicate that the accumulation of simple ganglioside species GM2 and GM3 may be indicative of a mechanism of interaction between AD and stroke.

Characterization of discontinuous buffer junctions using pH indicators in capillary electrophoresis for protein preconcentration

An effective sample preconcentration technique for proteins and peptides was recently developed using capillary electrophoresis (CE) with discontinuous buffers [C.A. Nesbitt, J.T.-M. Lo, K.K.-C. Yeung, J. Chromatogr. A 1073 (2005) 175]. Two buffers of different pH created a junction to trap the sample molecules at their isoelectric points and resulted in over 1000-fold preconcentration for myoglobin within 30 min. To study the formation of pH junctions in CE, a pH indicator, bromothymol blue, is used in this work to reveal the pH changes at the discontinuous buffer boundary. Bromothymol blue (BTB) exhibits a drastic change in its visible absorption spectrum (300-600 nm) going from the acidic to basic pH conditions, and is therefore ideal for visualizing the changes in pH at the junctions created by various buffer combinations. Preconcentration of myoglobin was performed in discontinuous buffers containing BTB. Major differences in the BTB absorption profiles were identified from buffer systems that differ significantly in preconcentration performance, which in turn, allowed for the identification of ideal buffers for sample preconcentration. Up to 2000-fold preconcentrations of myoglobin were achieved in the buffer systems studied in this work. In addition, the role of the electroosmotic flow (EOF) on the preconcentration performance was investigated. A low EOF was found to be desirable, as the pH junction could stay longer in the capillary for accumulation of proteins. The pH junction also displayed characteristics to resist bandbroadening. Potential laminar flow resulted from the mismatched residual EOFs under the two pH conditions within the discontinuous buffers appeared to have minimal effect on the preconcentration. In fact, external applied pressure can be used to control the migration of the pH junction without compromising the protein preconcentration.

Immunological studies of Revitonil, a phytopharmaceutical containing Echinacea purpurea and Glycyrrhiza glabra root extract

A phytopharmaceutical containing an extract of Echinacea purpurea and Glycyrrhiza glabra root (Revitonil tablets) was investigated for its suggested immunostimulating potential, using several in vitro tests and the in vivo carbon-clearance model in mice. In the in vitro phagocytosis test with human granulocytes, Revitonil showed a 44-53% stimulating effect at a concentration of 100 microg/ml. Whereas in the chemoluminescence test at a concentration of 1.25 microg/ml, Revitonil tablets exhibited a moderate enhancing effect only, a remarkable stimulating activity (30-50%) was observed in the T-lymphocyte CD69 bioassay at a concentration of 100 microg-1 microg/ml. The highest immunological efficacy could be assigned to Revitonil as revealed by the in vivo carbon-clearance model in mice. With RCt/RCc-values of 2.0, Revitonil exhibited a very high carbon elimination rate at oral administration. Because the Echinacea and Glycyrrhiza monoextracts alone showed lower RCt/RCc-values (1.3-1.7) than Revitonil, a potentiating synergistic effect of the extract mixture in Revitonil can be postulated.

Rhamnopyranosylgalactofuranan, a new immunologically active polysaccharide from Thamnolia subuliformis

A complex polysaccharide, Ths-3, consisting mainly of rhamnopyranosyl and galactofuranosyl units, has been isolated from the water extract of the lichen Thamnolia subuliformis using ethanol fractionation, dialysis, ion-exchange chromatography, gel filtration and preparative GP-HPLC. The mean M(r) of Ths-3 was determined to be 1450 kD, and the monosaccharide composition is gal/rha/glc/xyl/man in the ratio of 40:31:13:10:6. The structure of Ths-3 was further elucidated by methylation analysis by GC-MS and NMR spectroscopy and found to be basically composed of (1-->3)-linked beta-D-galactofuranosyl units with branches on C6, and rhamnosyl units being predominantly (1-->2)-linked with branches on C3 and C4, while some units are (1-->3)-linked. Glucose, mannose and galactofuranose are found as terminal units and glucose and mannose are also (1-->4)-linked, while xylose is only present as terminal units. The trisaccharide xylglcglc was detected after partial hydrolysis of the polysaccharide. The immunomodulating activity of Ths-3 was tested in an in vitro phagocytosis assay and the classical anticomplementary assay, and proved to be active in both tests. The authors suggest the trivial name thamnolan for Ths-3.

Immunologically active (1-->3)-(1-->4)-alpha-D-glucan from Cetraria islandica

A polysaccharide, Ci-3, resembling isolichenan except with a much higher degree of polymerization, has been isolated from the water extract, as well as from the alkali extract, of the lichen Cetraria islandica (L.) using ethanol fractionation, dialysis, ion-exchange chromatography and gel filtration. The mean M(r) of Ci-3 was determined to be 2000 kD, compared to 6-8 kD reported for isolichenan. The structure of Ci-3 was elucidated and found to be composed of (1-->3)- and (1-->4)-alpha-D-glucopyranosyl units in the ratio of 2:1, using methanolysis, methylation analysis, optical rotation and NMR spectroscopy. The immunomodulating activity of Ci-3 was tested in an in vitro phagocytosis assay and anti-complementary, and proved to be active in both tests.

Results of five randomized studies on the immunomodulatory activity of preparations of Echinacea

This article describes and discusses five placebo-controlled randomized studies investigating the immunomodulatory activity of preparations containing extracts of Echinacea in healthy volunteers. A total of 134 (18 female and 116 male) healthy volunteers between 18 and 40 years of age were studied. Two studies tested intravenous homeopathic complex preparations containing Echinacea angustifolia D1 (study 1) and D4 (study 5). Two studies (2 and 3a) tested oral alcoholic extracts of roots of E. purpurea, one study an extract of E. pallida roots (study 3b), and one study an extract of E. purpurea herb (study 4). Test and placebo preparations were applied for four (study 5) or five (studies 1-4) consecutive days. The primary outcome measure for immunomodulatory activity was the relative phagocytic activity of polymorphonuclear neutrophil granulocytes (PNG), measured in studies 1 and 2 with a microscopic method and in studies 3, 4, and 5 with two different cytometric methods. The secondary outcome measure was the number of leukocytes in peripheral venous blood. Safety was assessed by a screening program of blood and other objective parameters as well as by documentation of all subjective side effects. In studies 1 and 2 the phagocytic activity of PNG was significantly enhanced compared with placebo [maximal stimulation 22.7% (95% confidence interval 17.5-27.9%) and 54.0% (8.4-99.6%), respectively], while in the other studies no significant effects were observed. Analysis of intragroup differences revealed significant changes in phagocytic activity during the observation periods in five test and three control groups. Leukocyte number was not influenced significantly in any study. Side effects due to the test preparations could not be detected. Our studies provide evidence for immunomodulatory activity of the homeopathic combination tested in study 1 and the E. purpureae radix extract tested in study 2. The negative results of the other three studies are difficult to interpret due to the different methods for measuring phagocytosis, the relevant changes in phagocytic activity within most placebo and treatment groups during the observation period, and the small sample sizes. Future studies should be performed on patients rather than healthy volunteers and use standardized or chemically defined monopreparations of Echinacea.

Immunologically active polysaccharide from Cetraria islandica

A new alkali-soluble polysaccharide has been isolated from Iceland moss, Cetraria islandica (L.) Ach., by ethanol fractionation, ion-exchange chromatography, and gel filtration. The mean M(r) was estimated to be 18,000. Sugar and methylation analysis, partial hydrolysis, and 13C-NMR spectroscopy showed the polysaccharide to be a branched galactomannan with a backbone composed of two structural elements; (1-->6)-linked alpha-D-mannopyranosyl and alpha-D-(1-->6)-galactopyranosyl units. The polysaccharide showed pronounced immunostimulating activity in an in vitro phagocytosis assay and in the in in vivo carbon clearance assay.

[Immunologic studies of plant combination preparations. In-vitro and in-vivo studies on the stimulation of phagocytosis]

The activity of phagocytosis was tested in the in vitro granulocyte test and the in vivo carbon-clearance-test in the mouse for an extract combination consisting of four plant extracts (Echinacea angustifolia, Eupatorium perfoliatum, Baptisia tinctoria and Arnica montana). In both immune models, a step by step stimulation of the activity of phagocytosis by the addition of the four plant extracts was shown with an increase in effectiveness of partially over 50% in comparison to the pure Echinacea angustifolia mono-extract. The extract combination showed also in both test models a higher efficiency than two other differently composed combination preparations and two Echinacea mono-preparations.

In vitro stimulation of human granulocytes and lymphocytes by pico- and femtogram quantities of cytostatic agents

The influence of a broad concentration range of naturally occurring naphthoquinones and other cytotoxic or cytostatic agents (azathioprine, colchicine, cyclophosphamide, fluorouracil, methotrexate and vincristine) on human granulocytes and lymphocytes was investigated in a systematic in vitro study. At high concentrations (100 micrograms-10 ng/ml) nearly all substances showed the known cytotoxic or immunosuppressive effects, whereas most of the same compounds displayed immunostimulating activities at very low concentrations (10 ng-10 fg/ml). After a cold shock or heat treatment lymphocytes became more sensitive against these compounds in the active concentration range than untreated cells. These results possibly give an explanation for the antitumour activity of some plant extracts, for which a direct cytotoxicity due to the applied low dose can be excluded.

[Immunologic in vivo and in vitro studies on Echinacea extracts]

Ethanolic extracts of Echinacea purpurea, E. pallida and E. angustifolia roots were examined for immunological activity in the carbon clearance test with mice and in the granulocyte test. In the in vivo experiment all extracts, administered orally, were found to enhance phagocytosis significantly. These results correlate with the stimulation of phagocytosis in the in vitro granulocyte test. The lipophilic fractions of the extracts appeared to be more active than the polar fractions. All extracts were analyzed by HPLC in order to correlate the chemical constituents with the immunological activities.

[Effect of homeopathic drugs on the phagocytic activity of human granulocytes. In vitro tests in a controlled single-blind study]

Four homeopathic drug preparations with extract dilutions between D1 and D30 (expression for the homeopathic grade of potencies) and some additives (minerals and animal toxins) were investigated, using two in vitro and one in vivo phagocytosis models. All preparations enhanced significantly the activity of phagocytosis in all used systems. In controlled prospective single-blind studies with the preparations C and D performed on 12 and 14 verum and 13 male placebo volunteers respectively with i.v. injections within a 5-day treatment the phagocytosis indices were measured during 11 days using the microscopic smear method. In both investigations the maximum of phagocytosis activity was reached between the 4th and 5th day of injection. After the 4th or 5th (next to the last or last) injection, a rapid decrease of activity occurred which reached normal values on the 11th day. Other laboratory parameters investigated were not influenced.

Die Alkaloide von Uncaria tomentosa und ihre Phagozytose-steigernde Wirkung

From the roots of UNCARIA TOMENTOSA six oxindol alkaloids have been isolated and identified as isopteropodin, pteropodin, mitraphyllin, isomitraphyllin, rynchophyllin and isorynchophyllin. By ion pair chromatography on HPLC a fingerprint analysis has been worked out which allowed to differentiate between various UNICARIA-species and drug preparations. With the exception of mitraphyllin and rynchophyllin all alkaloids showed a pronounced enhancement effect on phagozytosis, determined in two IN VITRO tests and the IN VIVO-carbon clearance test.

Inhaltsstoffe und Pharmakologie der Okoubaka aubrevillei-Rinde

From the stembark of OKOUBAKA AUBREVILLEI (+)-catechin, (-)-epicatechin, (+)-gallocatechin, (-)-epicatechingallate, (-)-epigallocatechingallate, gallic and protocatechuic acid have been isolated. The antimicrobial and immunostimulating activity of the drug extract were assigned to the phenolic compounds.

[Immunostimulant action of polysaccharides (heteroglycans) from higher plants. Preliminary communication]

From the water or alcaline-water extracts of Echinacea purpurea (L.) Moench and -angustifolia DC., Eupatorium cannabinum L. and -perfoliatum L., Chamomilla recutita (L.) (Rauscher), Calendula officinalis L., Baptisia tinctoria (L.) R.B., Achyrocline satureoides DC., Arnica montana L., Sabal serrulata Roem et Schult. and Eleutherococcus senticosus Maxim. polysaccharide fractions with molecular weights in the range of 25 000 to 500 000 and higher have been isolated, which, according to the granulocytes- and carbon clearance tests, showed significant immunostimulating activities. The isolated compounds belong to the group of water-soluble, acidic heteroglycanes. The linkages in the different polysaccharides do not represent a uniform structure type.

Chemistry, 13C-NMR Study and Pharmacology of Two Saponins from Colubrina asiatica

From the leaves of COLUBRINA ASIATICA B RONGEN (Rhamnaceae) two saponins have been isolated and structurally elucidated, mainly by (13)C-NMR-spectroscopic methods, as jujubogenin-3-O-[2-O-acetyl-3-O-(3-O-beta-D-xylopyranosyl-4-O-acetyl-beta-D-glucopyranosyl)-alpha-L-arabinoside] (colubrinoside) and jujubogenin-3-O- [2-O-acetyl -3-O- (2-O- beta -D- xylopyranosyl-beta-D-glucopyranosyl)-alpha-L-arabinoside] (colubrin) respectively. Both saponins inhibit the spontaneous motility of mice, even at low doses (1 mg/ kg), they show an antagonistic effect on amphetamine and exert a synergistic activity on chlordiazepoxide.