Effects Of Mistletoe Research Articles

The effects of European mistletoe (Viscum album L.) on urban tree health

Background. Urban forests play a crucial role in making the urban environment and provide for sustainable development of urban areas. At the same time, urban habitats are stressful for trees therefore the latter become more susceptive to a range of disturbances, in particular to biotic agents such as the European mistletoe. The paper aims to evaluate the detrimental impacts of this hemiparasitic plant on urban trees. Materials and Methods. The study was conducted in an urban watershed of central and northwestern parts of the city of Kharkiv, Ukraine. Urban tree health survey took place in different stand types along 4 transects of the total length of 6.54 km. Totally, 956 individual trees were surveyed during the vegetation season of 2019. The health status of individual trees was assessed applying the 7-grade scale after O. D. Maslov, modified by the Ukrainian Forestry Research Institute. The mistletoe presence on individual trees was quantified using a semi-logarithmic index. The statistical analysis of the data collected involved the comparison of two empirical distributions, the normality test of the initial data, and the determination of the relationship between two independent samples. Results and Discussion. The analysis of the collected data revealed that the studied trees divided into two groups – “non-infested” and “mistletoe-infested” – grew in quite similar conditions and showed quite similar distribution by stand types, classes of soil conditions and age classes. We found differences in the mean health status between non-infested (transient from “weakened” to “dry-top”), and mistletoe-infested trees (“dry-top”): the tree health index of 2.43±0.03 for the former vs. 2.98±0.08 for the latter. Empirical distributions of the number of trees by the tree health classes in both groups were different too (the Kolmogorov–Smirnov criterion λ = 3.14 at Р >0.999). We found a significant positive correlation between both mistletoe abundance and the age of individual infested trees (Spearman’s R = 0.36 at Р >0.999), as well as the health index of individual infested trees (Spearman’s R = 0.23 at Р >0.95). Conclusions. The study has proven a negative effect of mistletoe’s infestation on the tree crown foliage assessed with the tree health index. Such an effect increases with the age of infested trees. The findings of this study suggest that in urban forests the mistletoe acts as a trigger towards acceleration of tree stand health deterioration.

Effects of mistletoe leaf (Viscum album) aqueous extracts on performance, hematology and serum biochemistry of rabbits in a humid tropical environment

The study examined the physiological effects of mistletoe leaves Aqueous Extracts (MLAE) on the performance, haematology and some serum biochemistry of rabbits. Thirty New Zealand white x Chinchilla weaned rabbits of 28days old were matched for weight, sex and randomly assigned to five groups (n=6 per-group), sub-divided into two replicates of three rabbits each. The basal diet was forages Tridax procumbens and Ipomea batata leaves 20 g morning and evening daily as common rabbit feed available in the environment. The rabbits were served twice daily with mistletoe leaves aqueous extracts 200mls of 20g dried leaves from four host trees and water 200 ml twice daily as control. All rabbits were fed ad libitum throughout the ten weeks period of the study. The proximate results revealed that mistletoe leaves from the four host trees were rich in crude protein, crude fibre and ash, which provided protein and minerals supplement for rabbits’ performance. Data obtained were subjected to one-way ANOVA and significant means separated using Turkey’s Comparision Test. Results on performances showed significant(P<0.05) difference between treatments indicated with the following ranges: final body weight (1220.00–1490.00g), daily weight gain (9.86-11.40g/d). Feed conversion ratio (0.11-0.86), total feed intake (4122.00–4392.00), total water and mistletoe aqueous extracts (8974.00-11627.00mls), Heamatology and serum biochemistry analysis results revealed significant p<0.05) difference between treatments compared to the control. The differences between the treatments could be attributed to mistletoe and their host trees, since mistletoe are hemi-parasites, depend partly on their host for nourishment. Extracts yielded good rabbit performance and blood physiological response, hence it could be used for forage–concentrate feed supplement for rabbits during dry season scarcity of forages.

From leaves to the whole tree: Mistletoe effects on the productivity, water relations, and demography of a Neotropical savanna tree

AbstractTrees' responses to mistletoes occur at multiple organization levels (e.g., leaf, individual, population), yet integrating these multi‐scale responses is still challenging. Here, we compared the traits of infected versus uninfected trees over multiple scales, from leaf anatomy and physiology to canopy allometries and individual growth rate and survivorship. We tested the hypotheses that mistletoes lead in the host (1) the production of leaves with a conservative resource‐use strategy, (2) more mechanically stable canopies and (3) reductions in growth and survival probability in the trees they infect. We addressed these hypotheses in the widespread savanna tree Vochysia thyrsoidea and xylem‐tapping mistletoe Psittacanthus robustus in the Brazilian Cerrado, a global biodiversity hotspot. We found that (1) mistletoe infection did not affect key traits associated with resource conservativeness, such as leaf mass per area (LMA) and carbon assimilation rates (A). Likewise, (2) hosts did not increase the mechanical safety of their trunks in response to mistletoe infection since infected and uninfected trees had a similar allometric scaling between height and crown volume against stem diameter. (3) At the population level, both the relative growth rate and survival probability decreased as the number of parasites increased. However, zero growth and a 50% chance of mortality were estimated to occur in a minority of heavily infected trees (>7 and 14 parasites, respectively). Our results challenge the idea that mistletoes have a ubiquitous negative impact on their hosts. We highlight, therefore, the need for clarifying the mechanisms that allow trees to maintain their functioning even in the face of mistletoe parasitism.

Changes in Antioxidative Compounds and Enzymes in Small-Leaved Linden (Tilia cordata Mill.) in Response to Mistletoe (Viscum album L.) Infestation.

Mistletoe infestation leads to a decrease in the growth of woody plants, their longevity, and partial or complete drying of the top, as well as premature death. Various environmental stress factors, both abiotic and biotic, stimulate the formation of reactive oxygen species and the development of oxidative stress in plant tissues. This study aimed to investigate the effect of mistletoe (Viscum album L.) infestation on the response of the antioxidative defense system in leaves of small-leaved linden (Tilia cordata Mill.). Leaves from infested trees were taken from branches (i) without mistletoe, (ii) with 1–2 mistletoe bushes (low degree of infestation), and (iii) with 5–7 mistletoe bushes (high degree of infestation). The relative water content and the chlorophyll a and b contents in leaves from linden branches affected by mistletoe were significantly lower than those in leaves from non-infested trees and from host-tree branches with no mistletoe. At the same time, leaves from branches with low and high degrees of infestation had significantly higher electrolyte leakage, malondialdehyde and hydrogen peroxide content, oxidized forms of ascorbic acid (dehydroascorbic and 2,3-diketogulonic acids), and oxidized glutathione. The results of principal component analysis show that the development of oxidative stress was accompanied by an increase in proline content and in superoxide dismutase, ascorbate peroxidase, glutathione peroxidase, and glutathione reductase activity. Several biochemical parameters (proline, ascorbic acid, dehydroascorbic acid, glutathione, glutathione peroxidase, ascorbate peroxidase, and dehydroascorbate reductase) were found to be altered in leaves from host-tree branches with no mistletoe. This result indicates that the mistletoe infestation of trees not only causes local changes in the locations of hemiparasite attachment, but also affects the redox metabolism in leaves from other parts of the infested tree.

Präklinische Untersuchungen von Wechselwirkungen zwischen Mistel und Radio- oder Chemotherapie auf pädiatrische Tumorzellen

Hintergrund: Mistelanwendungen werden als komplementäre Therapien häufig in der pädiatrischen Onkologie zusammen mit einer Radio- oder Chemotherapie verabreicht. Wechselwirkungen bei simultaner Applikation sind gerade in der Pädiatrie von großer Bedeutung, sie sind allerdings nach wie vor unzureichend untersucht. Material und Methoden: Zytotoxische Effekte des Mistelextraktes abnobaVISCUM Fraxini (aVF) auf LAN-1 Neuroblastomzellen und deren Etoposid- bzw. Cisplatin-resistente Subzelllinien wurden mittels Viabilitätstest untersucht, sowie mögliche Synergieeffekte zwischen aVF und den Chemotherapeutika durch die Softwareprodukte Combenefit und CompuSyn analysiert. Effekte einer Kombinationstherapie aus aVF und Bestrahlung auf SH-SY5Y Zellen wurden mittels Koloniebildungstest untersucht und Auswirkungen auf die Reparatureffizienz strahleninduzierter Doppelstrangbrüche mit Hilfe durchflusszytometrischer Quantifizierungen von γ-H2AX-Foci nach PI/FITC Doppelfärbung analysiert. Ergebnisse: Die Chemotherapie-resistenten LAN-1 Subzelllinien erwiesen sich als resistenter gegenüber der Mistelbehandlung als die Ursprungszelllinie. Auf Basis vier verschiedener Referenz­modelle konnten vor allem synergistisch/additive Effekte zwischen aVF und den Zytostatika Etoposid und Cisplatin berechnet werden. Die Kombination aus Mistelbehandlung und Bestrahlung führte zu einer Verringerung der Koloniebildung und zu einer Verzögerung der Reparaturgeschwindigkeit von strahleninduzierten Doppelstrangbrüchen. Schlussfolgerung: Die präklinischen Daten könnten darauf hinweisen, dass die Verwendung des Mistelextraktes, aVF, eine unterstützende Wirkung auf Radio- und Chemotherapien hat.

Dwarf Mistletoe Infection Interacts with Tree Growth Rate to Produce Opposing Direct and Indirect Effects on Resin Duct Defenses in Lodgepole Pine

Research Highlights: I sought to disentangle the influences of tree age, growth rate, and dwarf mistletoe infection on resin duct defenses in lodgepole pine, Pinus contorta Douglas ex Loudon, revealing the presence of direct positive and indirect negative effects of mistletoe on defenses. Background and Objectives: For protection against natural enemies, pines produce and store oleoresin (resin) in ‘resin ducts’ that occur throughout the tree. Dwarf mistletoe, Arceuthobium americanum Nutt. ex Engelm. (hereafter “mistletoe”), is a widespread parasitic plant affecting the pines of western North America. Infection by mistletoe can suppress pine growth and increase the probability of insect attack—possibly due to a reduction in resin duct defenses or in the potency of chemical defenses at higher levels of mistletoe infection, as reported in Pinus banksiana Lamb. However, the influence of mistletoe infection on defenses in other pine species remains unclear. I hypothesized that mistletoe infection would induce greater resin duct defenses in P. contorta while simultaneously suppressing annual growth, which was expected to reduce defenses. Materials and Methods: Using increment cores from P. contorta trees occurring in a subalpine forest of Colorado, USA, I quantified tree age, annual growth, annual resin duct production (#/annual ring), and cross-sectional area (mm2 of resin ducts/annual ring). Results: Mistletoe infection increased with tree age and had a direct positive relationship with resin duct defenses. However, mistletoe infection also had an indirect negative influence on defenses via the suppression of annual growth. Conclusions: Through the combined direct and indirect effects, mistletoe infection had a net positive impact on resin duct production but a net negative impact on the total resin duct area. This finding highlights the complexity of pine defense responses to natural enemies and that future work is needed to understand how these responses influence overall levels of resistance and the risk of mortality.

Tree growth declines and mortality were associated with a parasitic plant during warm and dry climatic conditions in a temperate coniferous forest ecosystem.

Insects and pathogens are widely recognized as contributing to increased tree vulnerability to the projected future increasing frequency of hot and dry conditions, but the role of parasitic plants is poorly understood even though they are common throughout temperate coniferous forests in the western United States. We investigated the influence of western hemlock dwarf mistletoe (Arceuthobium tsugense) on large (≥45.7cm diameter) western hemlock (Tsuga heterophylla) growth and mortality in a 500year old coniferous forest at the Wind River Experimental Forest, Washington State, United States. We used five repeated measurements from a long-term tree record for 1,395 T. heterophylla individuals. Data were collected across a time gradient (1991-2014) capturing temperature increases and precipitation decreases. The dwarf mistletoe rating (DMR), a measure of infection intensity, varied among individuals. Our results indicated that warmer and drier conditions amplified dwarf mistletoe effects on T. heterophylla tree growth and mortality. We found that heavy infection (i.e., high DMR) resulted in reduced growth during all four measurement intervals, but during warm and dry intervals (a) growth declined across the entire population regardless of DMR level, and (b) both moderate and heavy infections resulted in greater growth declines compared to light infection levels. Mortality rates increased from cooler-wetter to warmer-drier measurement intervals, in part reflecting increasing mortality with decreasing tree growth. Mortality rates were positively related to DMR, but only during the warm and dry measurement intervals. These results imply that parasitic plants like dwarf mistletoe can amplify the impact of climatic stressors of trees, contributing to the vulnerability of forest landscapes to climate-induced productivity losses and mortality events.

The effects of mistletoe (Viscum album L.) on the physiological properties of some drupe trees in Turkey

In the present study, the effects of mistletoe (Viscum album L.) on the physiological properties of drupe trees were investigated. In order to achieve this goal, sulfhydryl, chlorophyll a and b, total chlorophyll, ascorbic acid, total amino acid, proline, carotenoid, glucose, and fructose levels, as well as leaf proportional water contents were determined in both mistletoe and its hosts under laboratory conditions. According to the results, mistletoe caused a significant decrease in water content and reduced total ascorbic acid content in apricot, almond, and plum. Additionally, mistletoe did not affect the total amino acid, glucose, and fructose concentrations of the hosts. Carotenoid and total chlorophyll contents, on the other hand, were statistically similar in the control and hosts in almond and apricot. It was also observed that mistletoe had virtually no effect on the amount of chlorophyll a in all hosts; however, it affected chlorophyll b content. As a semiparasite, mistletoe caused branches to drift backwards from the tip of their shoots by using the water and other nutritional elements of the host tree, as well as clogging their xylems with its haustorium. In addition, mistletoe acts as a stress factor, increasing host proline and sulfhydryl levels and, thereby, causing the branches to drift backwards.

Mistletoe in oncological treatment: a systematic review : Part1: survival and safety.

Mistletoe treatment of cancer patients is discussed highly controversial in the scientific literature. Aim of this systematic review is to give an extensive overview about current state of research concerning mistletoe therapy of oncologic patients regarding survival, quality of life and safety. In September and October 2017 Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), PsycINFO, CINAHL and "Science Citation Index Expanded" (Web of Science) were systematically searched. The search strategy identified 3647 hits and 28 publications with 2639 patients were finally included in this review. Mistletoe was used in bladder cancer, breast cancer, other gynecological cancers (cervical cancer, corpus uteri cancer, and ovarian cancer), colorectal cancer, other gastrointestinal cancer (gastric cancer and pancreatic cancer), glioma, head and neck cancer, lung cancer, melanoma and osteosarcoma. In nearly all studies, mistletoe was added to a conventional therapy. Patient relevant endpoints were overall survival (14 studies, n = 1054), progression- or disease-free survival or tumor response (10 studies, n = 1091). Most studies did not show any effect of mistletoe on survival. Especially high quality studies do not show any benefit. With respect to survival, a thorough review of the literature does not provide any indication to prescribe mistletoe to patients with cancer.

Viscothionin purified from mistletoe (Viscum album var. coloratum Ohwi) induces insulin secretion from pancreatic beta cells

Ethnopharmacological relevanceMistletoe (Viscum album), an evergreen parasitic plant, has been widely used as an oriental phytomedicine to treat diabetes mellitus. However, it is unknown which mistletoe constituent exerts the beneficial effect against the disease. In this study, we examined the hypoglycemic activity of mistletoe and investigated whether the polypeptide viscothionin, purified from mistletoe, was responsible for the activity. Materials and methodsMistletoe extracts were prepared by heating mistletoe powder made of leaves and twigs in water for 3, 6, 9, and 12 h. Rat insulinoma RINm5F cells were used to test the cytotoxicity of the extracts and their effects on the secretion of insulin and its precursor, C-peptide. The inhibitory effects of a mistletoe extract on glucose absorption were measured using an α-glucosidase inhibition assay. To determine the component of mistletoe responsible for the observed effects, the mistletoe extract was precipitated with ethanol or hydrolyzed with a protease for further testing. A potential active constituent of mistletoe was isolated by chromatography and molecular weight cut-off fractionation, and its ability to induce insulin secretion was investigated. ResultsA 12-h heat-treated mistletoe extract, showing no cytotoxicity, significantly increased the secretion of insulin and C-peptide by RINm5F cells and enhanced the expression of glucose transporter type 4 (GLUT-4), insulin receptor substrate 1 (IRS-1), and protein kinase B (also known as AKT) in differentiated C2C12 cells. The extract also inhibited α-glucosidase activity. After ethanol precipitation, the extract showed much stronger effects on insulin- and C-peptide-secreting activities of cells, whereas the enzyme-hydrolyzed extract was less effective than the original extract, suggesting that the effect was mediated by a proteinaceous constituent of mistletoe. Subsequent analysis showed that viscothionin, a heat-stable 6-kDa polypeptide isolated from mistletoe, increased the level of insulin secretion by more than 20-fold compared to that induced by the extract. ConclusionsOur study indicates that the hypoglycemic effect of mistletoe is mediated by its insulinotropic action and α-glucosidase inhibitory activity, and the effect is due to viscothionin, one of the major bioactive constituents of mistletoe.

The effect of mistletoe (Viscum album) on branch wood and needle anatomy of Scots pine (Pinus sylvestris)

ABSTRACTMistletoes are hemi-parasitic plants growing on many tree species. They grow on the tree branches or trunk of a tree and form root-like structures called haustoria that penetrate into the tree, taking up water and mineral nutrients. Mistletoe is capable of causing a variety of effects to its hosts, including changes in wood formation and leaf development. We investigate and discuss the effects of pine mistletoe (Viscum album ssp. austriacum, Santalaceae) on branch wood and needle anatomy of Scots pine (Pinus sylvestris, Pinaceae). Parasitized and nonparasitized branches of Scots pine were sampled from host tree crowns of trees growing on the same site. Branches were taken from mid-crown facing south. They were cut at 2 cm proximal and 2 cm distal to the mistletoe on each host branch and at the corresponding position in the case of uninfected branches from the same host. The wood anatomy at proximal and distal parts and the parts at the corresponding position in the non-parasitized section was compared. The anatomy of one-year-old needles from both parasitized and non-parasitized branches was also compared. Mistletoe had significant influences on wood and needle anatomy. The major changes were the decreases in the double wall thickness, lumen area, tangential lumen area and radial lumen area of the tracheids in the wood and a decrease in vascular area in the needles. These results help to understand how mistletoe acts on its host.

Mistletoe effects on the host tree Tapirira guianensis: insights from primary and secondary metabolites

Mistletoes are parasitic plants that are capable of penetrating the living tissue of another plant’s stems and branches and extracting the necessary resources for their survival. This study aimed to compare the leaves and branches of parasitized and non-parasitized Tapirira guianensis host trees to gain insights of reciprocal effects of Phoradendron perrottetii (mistletoe) infection and profiles of primary metabolites and phenolic compounds of T. guianensis. Our hypothesis was that either the host’s chemical profile determines mistletoe infestation, or that the mistletoe infestation leads to fundamental changes in the metabolite profile of the host. Plant material was collected from T. guianensis parasitized by P. perrottetii, yielding samples from infested and non-infested host branches and their respective leaves. Infested branches were divided into two regions, the proximal region and the host-parasite interface (gall) region. Leaves and branches of non-parasitized plants were also collected. Statistical analyses revealed negative effects of the parasite on infested branches regarding most of the analyzed primary metabolites, especially soluble carbohydrates. This suggests a flow of carbohydrates towards the mistletoe, indicating a partially heterotrophic nutrition. Additionally, we observed a positive effect on the tannin contents of non-infested host branches caused by the mistletoe, which might suggest that this parasitic relationship induces a systemic response in T. guianensis. Finally, high contents of flavonoids at the gall region could indicate a mechanism of ROS quenching.

Ethanol extracts from the branch of Taxillus yadoriki parasitic to Neolitsea sericea induces cyclin D1 proteasomal degradation through cyclin D1 nuclear export

BackgroundAlthough the inhibitory effect of mistletoe on cancer cell growth has been reported, the underlying mechanisms to explain its anti-proliferative activity are not fully studied. Thus, we elucidated the potential molecular mechanism of the branch from Taxillus yadoriki (TY) parasitic to Neolitsea sericea (NS) (TY-NS-B) for the anti-proliferative effect.MethodsAnti-cell proliferative effect was evaluated by MTT assay. The change of cyclin D1 protein or mRNA level was evaluated by Western blot and RT-RCR, respectively.ResultsIn comparison of anti-proliferative effect of TY from the host trees such as Cryptomeria japonica (CJ), Neolitsea sericea (NS), Prunus serrulata (PS), Cinnamomum camphora (CC) and Quercus acutissima (QA), TY-NS showed higher anti-cell proliferative effect than TY-CJ, TY-PS, TY-CC or TY-QA. In addition, the anti-proliferative effect of branch from TY from all host trees was better than leaves. Thus, we selected the branch from Taxillus yadoriki parasitic to Neolitsea sericea (TY-NS-B) for the further study. TY-NS-B inhibited the cell proliferation in the various cancer cells and downregulated cyclin D1 protein level. MG132 treatment attenuated cyclin D1 downregulation of cyclin D1 protein level by TY-NS-B. In addition, TY-NS-B increased threonine-286 (T286) phosphorylation of cyclin D1, and the mutation of T286 to alanine (T286A) blocked cyclin D1 proteasomal degradation by TY-NS-B. But the upstream factors related to cyclin D1 degradation such as ERK1/2, p38, JNK, GSK3β, PI3K, IκK or ROS did not affect cyclin D1 degradation by TY-NS-B. However, LMB treatment was observed to inhibit cyclin D1 degradation by TY-NS-B, and T286A blocked cyclin D1 degradation through suppressing cyclin D1 redistribution from nucleus to cytoplasm by TY-NS-B. In addition, TY-NS-B activated CRM1 expression.ConclusionsOur results suggest that TY-NS-B may suppress cell proliferation by downregulating cyclin D1 protein level through proteasomal degradation via T286 phosphorylation-dependent cyclin D1 nuclear export. These findings will provide the evidence that TY-NS-B has potential to be a candidate for the development of chemoprevention or therapeutic agents for human cancer.

Effects of mistletoe (Phoradendron villosum) on California oaks.

Mistletoes are a widespread group of plants often considered to be hemiparasitic, having detrimental effects on growth and survival of their hosts. We studied the effects of the Pacific mistletoe, Phoradendron villosum, a member of a largely autotrophic genus, on three species of deciduous California oaks. We found no effects of mistletoe presence on radial growth or survivorship and detected a significant positive relationship between mistletoe and acorn production. This latter result is potentially explained by the tendency of P. villosum to be present on larger trees growing in nitrogen-rich soils or, alternatively, by a preference for healthy, acorn-producing trees by birds that potentially disperse mistletoe. Our results indicate that the negative consequences of Phoradendron presence on their hosts are negligible-this species resembles an epiphyte more than a parasite-and outweighed by the important ecosystem services mistletoe provides.

Quantifying the effect of pine mistletoe on the growth of Scots pine

SummaryMistletoe infection results in substantial growth losses in mistletoe‐infected forests. This study reports and evaluates the results of retrospective analyses of radial growth of Scots pine (Pinus sylvestris) in relation to the level of infection of pine mistletoe (Viscum album ssp. austriacum). A total of 43 Scots pine trees were destructively sampled from different sites. Of these trees, 14 were uninfected and 29 were infected. Infection classes were determined using six‐class dwarf mistletoe rating system (DMRS). All needle and mistletoe biomass were removed completely and weighed for each sampled tree. Subsamples from needles and all mistletoe biomass were taken to the laboratory for oven‐dried weight determinations. Five‐cm‐thick wood discs were cut from the stem at the breast height (1.3 m) to determine annual basal area increment for the last 25 years. In addition to DMRS, new infection classes were created using mistletoe‐to‐needle biomass (MB/NB) ratio. The results showed that the radial growth losses could be as much as 41% to 64% at different infection levels. The rate of growth loss in relation to DMRS and MB/NB ratio was similar, but with a larger variability in DMRS values. The results showed that both DMRS rating and MB/NB ratio seem to be important for quantifying growth loss on Scots pine trees infected with mistletoe. The results of this study can also be invaluable in modelling the effects of mistletoe on the growth of Scots pine trees.

Effect of mistletoe on endometrial stromal cell survival and vascular endothelial growth factor expression in patients with endometriosis.

Research Question: To evaluate the effect of mistletoe on the cell viability of patients with endometriosis, the expression levels of vascular endothelial growth factor (VEGF) were measured, and the change in the expression level of VEGF following mistletoe treatment was recorded.Design: Forty reproductive-aged women with endometriosis (stage I/II [group 1, n=20], and stage III/IV [group 2, n=20]) were prospectively enrolled. Twenty women who underwent gynaecologic operations for benign conditions were selected as the control group. Both eutopic and ectopic endometrial tissues were obtained from the endometriosis patients. The endometrial tissues were cultured and the stromal cells were separated. The cells were cultured for 24 hours with peritoneal fluid from patients and controls with and without mistletoe supplementation (200 ng/mL), respectively. The MTT assay was used to assess cell viability, and VEGF expression was analysed by Western blotting and ELISA.Results: Using peritoneal fluid from endometriosis patients treated with mistletoe, we found that both eutopic and ectopic endometrial stromal cell viability increased after treatment with peritoneal fluid from patients with early-stage (I and II) endometriosis. After mistletoe treatment, the cell viability was decreased, in both eutopic and ectopic endometrial stromal cells in all stages of endometriosis. These findings were verified consistently by evaluating the expression and concentration of VEGF, a marker of angiogenesis.Conclusions: The present study showed that mistletoe can reduce the cell viability of endometrial stromal cells and the peritoneal fluid-induced elevation of VEGF in eutopic and ectopic endometrial stromal cells obtained from endometriosis patients, especially in the early stage. Mistletoe might have anti-angiogenic activity on endometrial stromal cells and thus is a potential candidate for the treatment of endometriosis.

Effect of mistletoe combined with carboxymethyl cellulose on dry eye in postmenopausal women.

To investigate the protective effect of mistletoe combined with carboxymethyl cellulose eye drops on dry eye in postmenopausal women. Sixty postmenopause female patients diagnosed of dry eye were assigned randomly to mistletoe combined with carboxymethyl cellulose eye drops treatment group (n=30) and control group treated with normal saline eye drops (n=30). The subjective symptoms of ocular surface, Ocular Surface Disease Index (OSDI), tear film function tests, tear protein and corneal morphology by confocal scanning microscopy were analyzed before treatment and at 1, 2, 4 and 8wk after treatment respectively. To ensure the safety of the trial, all patients were examined with systolic pressure, diastolic pressure, glutamic-pyruvic transaminase, glutamic oxaloacetic transaminase, urine creatinine, and blood urea nitrogen at 8wk after treatment. There were no obvious differences between two groups before the treatment (P>0.05). In two months after the treatment, the symptoms of ocular surface, OSDI, tear protein, and tear film function were only slightly changed in normal saline eye drops group. However, all indices were improved after the treatment of mistletoe combined with carboxymethyl cellulose eye drops group (P<0.05). In addition, the average amount of corneal epithelium basal cells and inflammatory cells of mistletoe treated group were 3174±379 and 38±25 cells/mm2, significantly decreased as compared to the control group with 4309±612 and 158± 61 cells/mm2, respectively. In the control group, although nerves still maintained straight under corneal epithelium, the number of nerves were significantly decreased, as compared with normal female. In the mistletoe treated group, the number of nerves was only slightly reduced, compared with normal female. Mistletoe combined with carboxymethyl cellulose eye drops can alleviate the symptoms and signs of dry eye symptoms.

Parasites structuring ecological communities: The mistletoe footprint in Mediterranean pine forests

Abstract The capacity of parasitic plants in structuring natural communities is increasingly recognized. These plants can affect the structure, composition and productivity of plant communities by modifying the competitive balance between hosts and non‐host species and by altering the quantity and quality of resources entering the soil. Despite the progress made in this field, there is still a lack of integrative studies showing the structuring capacity of parasitic plants in forest ecosystems, where their effect may be less detectable due to the long life span of the system. In this study we evaluate the long‐term impact of Viscum album subsp. austriacum on the woody‐plant community of a Mediterranean pineland. This mistletoe remains several years on the same host, exerting long‐lasting, spatially concentrated effects on community and ecosystem characteristics. Mistletoe concentrates zoochorous seeds and induces changes in the soil fertility and light availability beneath the canopy of parasitized trees, which have the potential to facilitate zoochorous–plant colonization, recruitment, and growth at the same time as it weakens the host. Here, we analyse whether mistletoe‐driven changes could result in a nucleus of zoochorous woody plants nourished by the abundant organic detritus accumulated under the host. We also analyse whether mistletoe effects can expand after host death. We selected unparasitized, parasitized, and dead parasitized Pinus nigra trees, in which we studied the joint effect of mistletoe‐mediated changes in soil nutrient and light availability, with the seed rain, seed predation, seedling establishment, plant recruitment, and plant growth. Light‐ and soil‐nutrient resources were greater under parasitized trees, and intensified after host death. The seed rain was maximum under parasitized trees, where seedling recruitment proved more likely. Sapling density, richness, and growth increased with the development of parasitism. Our findings show that V. album exerts a strong and lasting impact on the structure and dynamics of Mediterranean pinelands, with parasitized trees acting as centres for the establishment and growth of colonizing fleshy‐fruited woody species, which, over the long term, promote vegetation shifts by limiting dominant pine trees and facilitating less represented fleshy‐fruited shrubs. A plain language summary is available for this article.

Methotrexate-Induced Nephrotoxicity in Rats: Protective Effect of Mistletoe (Viscum album L.) Extract

Background: The protective effect of mistletoe extract (Helixor®, HLX) against methotrexate (MTX)-induced acute oxidative stress and nephrotoxicity in rats was evaluated by histological and biochemical methods as well as the comet assay. Material and Methods: 32 female Wistar albino rats were divided into 4 groups: control group, HLX group (5 mg/kg body weight (bw), days 1-10, intraperitoneally (i.p.)), MTX group (10 mg/kg bw, days 7, 8, and 9, i.p.), and MTX + HLX group (10 mg/kg bw, days 7, 8, and 9, i.p. + 5 mg/kg bw, days 1-10, i.p.). At the end of the experiment, the glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), nitric oxide (NO), and myeloperoxidase (MPO) levels were measured, and a histopathological analysis and comet assay were carried out. Results: MTX induced renal oxidative stress and nephrotoxicity in the rats. Pretreatment with HLX significantly improved the renal GSH-Px and SOD activities in the MTX + HLX group compared to the MTX group. The decrease in the NO and MPO levels in the rat groups pretreated with HLX was not significant. The histochemical evaluation revealed that HLX provided significant improvement in the MTX-induced renal degenerative changes, including tubule distension, interstitial inflammation, perirenal inflammation, glomerular congestion, glomerular degeneration, and parenchymal hemorrhage, in the MTX + HLX group compared to the MTX-administered group. According to the comet assay, pretreatment with HLX lowered the MTX-induced DNA damage in endogenous lymphocytes, although not significantly. Conclusion: This study demonstrated that HLX administration markedly reduced the MTX-induced acute oxidative stress and nephrotoxicity in rats through its antioxidant and anti-inflammatory properties.

Viscum album (L.) in experimental animal tumors: A meta-analysis.

Mistletoe (Viscum album L.) has been used as complementary anticancer treatment for ~100 years. Although the clinical efficacy of mistletoe in cancer and associated survival benefits remain contested, several studies point to its effectiveness and others have reported antitumor and immunomodulatory properties. In the present review, a search was conducted for original articles reporting the outcomes of treatments for experimental animal tumors with mistletoe. The inclusion criteria were: Publication in English, from 1996 onwards and in peer-reviewed journals included in the database PubMed. The parameters analyzed were: Provenance and time of publication, rationale, methods (animal species used, mistletoe preparation, treatment protocol, tumor lineage, blinding, randomization, controls and concomitant treatments), outcomes and investigated mechanisms of action. A total of 37 studies met the inclusion criteria. The quality of the studies was adequate in the terms of sample size and use of controls, and the only animal species employed were mice and rats. However, few studies reported having performed random allocation and none reported blinding. There was wide variation in the type and preparation of mistletoe used, route of administration, regimen, tumor type and the mechanism of action assessed. A temporal trend was identified; earlier studies sought to establish the antitumor effect of mistletoe and its possible mechanisms, cytotoxicity and immunomodulation in particular, whereas the later ones tended to focus more on biologically active principles, genomics and oxidative stress. A total of 32/37 studies reported an antitumor effect, 3 of which had mixed results. A total of 2 studies did not detect any antitumor effect and a further 2 found stimulation of tumor growth in the treated groups. One study did not assess antitumor effects, investigating immunomodulation action instead. The quality of the studies was satisfactory and the majority reported positive outcomes. Nevertheless, there is a great deal of methodological heterogeneity among the studies, which precludes conclusive comparisons. Based on these results, the present authors strongly suggest developing guidelines for reporting in vivo mistletoe cancer treatment experiments.