SEARCH · Search PubMed

Results for “Mistletoe”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

PubMed1989

Influence of carbohydrates on the cytotoxicity of an aqueous mistletoe drug and of purified mistletoe lectins tested on human T-leukemia cells.

Partially and highly purified lectins from Viscum album L. (mistletoe) cause a dose-dependent decrease of viability of human leukemia cell cultures, MOLT-4, after 72 h treatment. The LC50 of the partially purified lectin was 27.8 ng/ml, of the highly purified lectin 1.3 ng/ml. Compared to the highly purified lectin a 140-fold higher protein concentration of an aqueous mistletoe drug was required to obtain similar cytotoxic effects on MOLT-4 cells. Cytotoxicity of the highly purified lectin was preferentially inhibited by D-galactose and lactose, cytotoxicity of the mistletoe drug and the partially purified lectin were preferentially inhibited by lactose and N-acetyl-D-galactosamine (GalNAc). Two lectin fractions with almost the same cytotoxic activity on MOLT-4 cells but with different carbohydrate affinities were isolated by affinity chromatography from the mistletoe drug: mistletoe lectin I with an affinity to D-galactose and GalNAc and mistletoe lectin II with an affinity to GalNAc. The lectin fractions and the mistletoe drug inhibited protein synthesis of MOLT-4 cells stronger than DNA synthesis. Furthermore a subpopulation of MOLT-4, resistant to cytotoxic doses of both the mistletoe drug and the mistletoe lectins, was shown to exhibit a reduced amount of GalNAc and N-acetyl-D-glucosamine in their cellular glycoproteins which are probably responsible for the binding of the cytotoxic lectins. These results indicate that lectins are the main toxins in the mistletoe drug.

Carbohydrates↗

PubMed1993

In vitro effects of mistletoe extracts and mistletoe lectins. Cytotoxicity towards tumor cells due to the induction of programmed cell death (apoptosis).

The in vitro effects of therapeutically administered mistletoe extracts (ABNOBAviscum) and pure mistletoe lectins (mainly mistletoe lectin I) on a variety of human and murine tumor cell lines have been investigated. Mistletoe extracts and purified mistletoe lectins inhibited in vitro the growth of all tumor cell lines tested including B cell hybridomas, P815, EL-4, Ke37, MOLT-4 and U937. The mechanism of growth arrest was shown to be due to the induction of programmed cell death (apoptosis). Thus, fragmentation of genomic DNA into oligonucleosomal bands of approximately 200 base pairs in length was observed within 20 h when tumor cells were incubated with mistletoe extracts or lectins. These data point to a rational basis for the direct cytotoxic effects of mistletoe extracts and lectins apart from the postulated immunostimulatory properties of these agents.

Adjuvants, Immunologic↗

PubMed1990

Anti-mistletoe lectin antibodies are produced in patients during therapy with an aqueous mistletoe extract derived from Viscum album L. and neutralize lectin-induced cytotoxicity in vitro.

The humoral response components of an aqueous mistletoe extract (HM) was evaluated in 23 tumor patients who had been treated from 2 months up to 6 years with increasing dosages of HM. IgG antibodies against mistletoe lectin and other components of this extract were detected by ELISA, immunodiffusion, and blotting technique, using either the aqueous extract (HM) or a purified lectin preparation (ML). Their activity depended upon dosage of HM and length of therapy. No anti-HM/ML antibodies of the IgM type could be detected. Immunoblotting revealed lectin-specific antigens at 62 kD, 33k D, and 29 kD. In the presence of ML or HM, PHA-induced proliferation of normal lymphocytes was decreased in a dose-dependent manner; this effect was neutralized by adding the IgG fraction from pooled anti-HM-antibody-positive sera, indicating that the cytotoxic effect of lectins was eliminated by these specific antibodies. In view of these findings, it is questionable whether exposing tumor cells to mistletoe extracts in vivo exerts the same direct effect on tumor cells that is observed in vitro.

Blotting, Western↗

PubMed1977

[Isolation and characterization of mistletoe extracts (Viscum album L.). I. Affinity chromatography of mistletoe extracts on immobilized plasma proteins].

The agglutinating effect of lectin from mistletoe (Viscum album L.) relative to erythrocytes and tumor cells is destroyed or reduced by plasma proteins. There is a competition between lectin receptors of plasma proteins, especially immunoglobulins and erythrocytes, as well as tumor cells. The preparation of insolubilized immunoglobin fractions allows one to separate lectin from the mistletoe extract. There exist chemical connections between the lectin fixed to the adsorbent and part of the toxic components.

Blood Proteins↗

PubMed1990

Characterization of cytotoxic proteins from mistletoe (Viscum album L.).

Proteins from a laboratory-made oak mistletoe extract and from the commercial mistletoe preparation Iscador Quercus were cytotoxic for leukemia Molt 4 cells in culture. A 50% growth inhibition was obtained with 0.1 microgram/ml proteins for the mistletoe extract and 0.025 microgram/ml for Iscador. On cation exchange chromatography, cytotoxic proteins from the mistletoe extract were mainly eluted at the same positions as purified lectins, while those of Iscador were eluted at the positions of viscotoxins. The data are discussed in relation to the pharmacological activities of the mistletoe protein complexes described in the literature.

Antineoplastic Agents, Phytogenic↗

PubMed1986

Recent studies on the anticancer activities of mistletoe (Viscum album) and its alkaloids.

Detailed methods for in vitro/in vivo evaluation of anticancer drugs, with special reference to mistletoe extracts, have been reviewed. Mistletoe extracts have been shown to possess significant antitumor activity, in vivo, against murine tumors, Lewis lung carcinoma, colon adenocarcinoma 38 and C3H mammary adenocarcinoma 16/C. Methods for the extraction of biologically active alkaloids from mistletoe and their anticancer activities are presented. The possible origin of alkaloids in mistletoe plants, and their contributions towards a mechanism of anticancer activities of mistletoe extracts, are proposed.

Alkaloids↗

PubMed1986

[Detection and quantitative determination of lectins and viscotoxins in mistletoe preparations].

Mistletoe lectins and viscotoxins, which up to now have been isolated only from plant material, were detected and quantitatively determined in the mistletoe preparation Iscador and in a fermented mistletoe extract. Lectins were isolated by affinity chromatography and analyzed by isoelectric focussing. Thus, in Iscador and in the fermented mistletoe extract only the mistletoe lectins ML II/III were found whereas typical proteins of the ML I complex were missing. The lectin content of the preparation and the extract was determined by "single radial immunodiffusion" (SRID). For identification and quantitative determination of viscotoxins, a HPLC method was designed.

Chromatography, Affinity↗

PubMed1986

Differences in the in vitro effectiveness of preparations produced from mistletoes of various host trees.

The in vitro effectiveness of three Helixor preparations produced from mistletoes of different host trees on suspension cell cultures of the human leukemia cell line Molt 4 has been compared by means of dose-response investigations. After 72 h treatment the preparation produced from mistletoes of the appletree (Malus) shows the strongest effect on the growth and viability of the cell cultures. The preparation produced from mistletoes of the fir (Abies) shows also an evident but much weaker effect, whereas the preparation produced from mistletoes of the pine (Pinus) causes a weak effect only at a very high dosage. As shown in 24-h incorporation experiments with 3H-labelled DNA-, RNA- and protein precursors the preparation produced from mistletoes of the apple-tree reduces the protein synthesis of the cells to a greater extent than the DNA-and RNA-synthesis.

Cell Line↗

PubMed1986

Assessing mistletoe toxicity.

To assess the potential toxicity of mistletoe ingestion, data were collected on 14 cases of ingestion of one to three berries or one or two leaves of American mistletoe (Phoradendron sp) from 1982 to 1985. Eleven patients ingested berries and three ingested leaves; none became symptomatic. Nine patients were observed at home without intervention except poison center telephone follow-up. Five had induced emesis, including two who were referred to emergency departments for evaluation, where no findings other than ipecac-induced vomiting were noted. Also reviewed were data on a total of 318 cases of mistletoe ingestion reported to the Food and Drug Administration Poison Control case reporting system between 1978 and 1983 (n = 177) and the American Association of Poison Control Centers national data collection system (n = 141) in 1984. The majority remained asymptomatic and no deaths were recorded. These data allow the conclusion that ingestion of one to three mistletoe berries or one or two leaves is unlikely to produce serious toxicity.

Adolescent↗

PubMed1986

Mistletoe lectins and their A and B chains.

Mistletoe lectins are of high biological activity. The mistletoe lectin I (ML I) is a naturally occurring conjugate of an enzyme (A chain) and a lectin (B chain). Its cytotoxicity is caused by inhibiting the protein synthesis on the ribosomal level. Prominent properties of the A chain are mitogenicity and inhibition of the protein synthesis in cell-free systems. The A chain is also a candidate for the construction of immunotoxins. The B chain as well as the intact lectins activate macrophages and release lymphocytes. They both inhibit the allergen-induced histamine release from leukocytes and the collagen-induced serotonin release from platelets. It cannot be excluded that the combination of selectively cytotoxic and immunopotentiating properties of mistletoe lectins and their chains are decisive for the therapeutic effects of mistletoe preparations.

Animals↗

PubMed1991

Demonstration of specifically sensitized lymphocytes in patients treated with an aqueous mistletoe extract (Viscum album L.).

Lymphocytes of 25 patients treated with an aqueous mistletoe extract (Viscum album L.) for up to 6 months (group 1), up to 2 years (group 2), and more than 2 years (group 3) were examined in 3- and 7-day cultures for specifically sensitized lymphocytes. The whole extract (HM), the lectin-polysaccharide fraction (HM-LP), and the 'viscotoxin' fraction (HM-V) were added at concentrations ranging from 0.5 micrograms to 12.5 mg extract/ml. Lymphocytes from four of the nine group 2 patients and five of the ten group 3 patients reacted specifically with HM and HM-LP at an optimal dose of 5.0 mg/ml, but did not react with HM-V. Stimulation indices varied between 1.6 and 16. In the patients of group 3 this effect was observed only when their lymphocytes were co-stimulated in the 3-day cultures with phytohemagglutinin (PHA), in contrast to the four patients of group 2 who reacted only in the 7-day cultures with HM-LP without PHA co-stimulation. Patients' lymphocytes had to be protected from mistletoe lectin-induced cytotoxicity by the addition of their own sera containing anti-mistletoe lectin antibodies. Lymphocytes from tumor patients (n = 18) never treated with mistletoe extracts and healthy individuals (n = 18) showed no specific proliferative response when tested in 3- and 7-day cultures.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibody Formation↗

PubMed1994

Anti-diabetic properties of the African mistletoe in streptozotocin-induced diabetic rats.

The African mistletoe, Loranthus bengwensis L. (Loranthaceae), has been widely used in Nigerian folk medicine to treat diabetes mellitus. The aqueous extract or infusion (1.32 g/kg per day) of the leaves of this plant parasitic on lemon, Citrus limon (L.) Brum f. (Rutaceae), guava, Psidium guajava L. (Myrtaceae) and jatropha, Jatropha curcas L. (Euphorbiaceae), respectively, were supplied ad libitum to separate groups of both non-diabetic and streptozotocin-induced diabetic rats, as their only source of fluid for a period of 28 days. The infusions of mistletoe parasite on both lemon and guava trees significantly decreased serum glucose levels in non-diabetic (P < 0.05) and diabetic (P < 0.001) rats, whereas that prepared from mistletoe parasitic on jatropha did not. The data indicate that African mistletoe possesses significant anti-diabetic activity in streptozotocin-induced diabetic rats; its anti-diabetic activity appears to be highly dependent on the host plant species.

Animals↗

PubMed1986

Effects of mistletoe (Viscum album L.) extracts on cultured tumor cells.

Bacterially fermented mistletoe preparations (BFMP) were tested on rat hepatoma tissue culture (HTC) cells and human leukemia Molt 4 cells. A dose-dependent inhibition of the growth rate of the cells was observed. For both cell lines, cytostatic concentrations, expressed in weight of fresh plant, were 0.5 mg/ml culture medium for oak BFMP and 1 mg/ml for apple tree BFMP. However, the action of the two preparations was markedly different on each cell line. Non-viable HTC cells were not stained by trypan blue while non-viable Molt 4 cells were fully colored by this reagent. A lysis of cellular membranes of HTC cells was observed by electron microscopy. Furthermore, oak BFMP inhibited the growth of virus transformed 3T3-SV40 cells more than that of non-transformed 3T3 cells. In contrast to BFMP, non-fermented extracts and a purified mistletoe lectin showed a greater inhibition of the growth of Molt 4 cells than of HTC cells. Samples withdrawn at different times during fermentation gradually lost their inhibitory effect on the growth of Molt 4 cells while their action on HTC cells increased up to the 4th day of fermentation. These results are discussed in relation to the cytotoxic substances of mistletoe already characterized.

Animals↗

PubMed1981

Mistletoe hepatitis.

A 49-year-old woman presented with nausea, general malaise, and a dull ache in the right hypochondrium. Liver biopsy showed slight inflammatory-cell infiltration, and results of liver function tests suggested hepatitis. Hepatitis B surface antigen was not detected, and a cholecystogram was normal. Two years later she presented with similar symptoms, and both illnesses were found to have occurred after ingestion of a herbal remedy containing kelp, motherwort, skullcap, and mistletoe. A challenge test established this to be the cause of the illness. Mistletoe is the only constituent of the tablets known to contain any potential toxin and thus was probably the cause of the illness. Mistletoe is widely used in herbal remedies, whose ingestion may therefore cause hepatitis.

Chemical and Drug Induced Liver Injury↗

PubMed1986

Studies on the standardization of mistletoe preparations.

The newly isolated phenylpropanoids syringin, syringenin-apiosylglucoside, eleutheroside E and the high molecular lectins and viscotoxins were selected for a standardization of mistletoe extracts and drug preparation. The phenylpropanoids found in all alcoholic and aqueous extracts were suitable for an HPLC fingerprint analysis, and for quantitative determination. The lectin content of the drug preparations was determined by single radial immunodiffusion. As shown by the isoelectric focussing method, Iscador and fermented mistletoe extracts contain only the mistletoe lectins ML II/III, whereas the proteins of the ML I complex are missing. For identification and quantitative determination of viscotoxins, an HPLC method was designed.

Chromatography, Affinity↗

PubMed1989

[Studies on pharmacological activity of the Japanese and European mistletoe].

The pharmacological actions such as analgesic effect, diuretic action, hypoglycemic activity and hypotensive action were studied on the methanol extract of the Japanese mistletoe and the European mistletoe. The both extracts showed the hypotensive action when administered intravenously to cat. The methanol extract of the Japanese mistletoe also showed a increase of K+ value in the urine when administered orally to rat.

Analgesics↗

PubMed1992

Comparative lectinhistochemical studies on paraffin- and glycol methacrylate-embedded CNS tissue specimens from AIDS autopsies. Mistletoe lectin I (ML I) as cell-marker.

Brain tissue and spinal cord tissue from 12 patients who had died of AIDS was fixed in neutral formalin; then after the embedment of some of it in paraffin and some of it in glycol methacrylate, it was analyzed lectinhistochemically with mistletoe lectin I (ML I). Mistletoe lectin (ML I) is a reliable marker for microglia cells and macrophages and for special cell forms (polynuclear giant cells, so-called pericytes) belonging to this cell system. In both the embedding procedures used, the representation of the cells is very clear and subtly differentiated so that the preparations are very well suited to the study of AIDS-associated tissue damage in the CNS. Whereas the immunological macrophage markers (CD 68 markers) KPI, PG-M1 produce good results on paraffin-embedded material but are completely useless on material embedded in glycol methacrylate, the cells of the monocyte-macrophage system can be represented very well and reliably after being embedded in glycol methacrylate with mistletoe lectin I (ML I).

AIDS Dementia Complex↗

PubMed1995

Quantitative determination of lectins in mistletoe preparations.

Assay of lectins in mistletoe preparations was based on an improved and validated version of ELLA (enzyme-linked lectin assay) to meet the requirements given in the guidelines for drug tests. The monoclonal antibody used has more than 90% cross reactivity with the three known mistletoe lectins, so that total lectin content is determined with much greater accuracy. With the detection and quantitative analysis limit below 5 ng/ml and a linear measuring range of 5-50 ng/ml, dosages in therapeutic range can be assayed. Tests to establish the accuracy of the analytical method showed that up to 26% of lectin activity is suppressed by other constituents of the extract, so that the recovery must be taken into account. The recovery increases following ultrafiltration to remove low-molecular constituents. Analysis for precision gave a variation coefficient of < or = 7.7% and a confidence interval < or = 5.7% (p = 0.05) for total lectin concentrations of approx. 250 ng/ml. This level of precision, which is good for an immunologic assay, makes it possible to standardize mistletoe preparations.

Antibodies, Monoclonal↗