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Christoph M. Schempp

Bio: Christoph M. Schempp is an academic researcher from University of Freiburg. The author has contributed to research in topics: Hypericum perforatum & Hyperforin. The author has an hindex of 34, co-authored 173 publications receiving 4794 citations. Previous affiliations of Christoph M. Schempp include University Medical Center Freiburg.


Papers
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Journal ArticleDOI
TL;DR: In vivo and in vivo, luteolin reduced increased vascular permeability and was effective in animal models of inflammation after parenteral and oral application, indicating that it has the potential to protect from diseases associated with inflammatory processes such as cardiovascular disease.
Abstract: Luteolin is a flavone which occurs in medicinal plants as well as in some vegetables and spices. It is a natural anti-oxidant with less pro-oxidant potential than the flavonol quercetin, the best studied flavonoid, but apparently with a better safety profile. It displays excellent radical scavenging and cytoprotective properties, especially when tested in complex biological systems where it can interact with other anti-oxidants like vitamins. Luteolin displays specific anti-inflammatory effects at micromolar concentrations which are only partly explained by its anti-oxidant capacities. The anti-inflammatory activity includes activation of anti-oxidative enzymes, suppression of the NFkappaB pathway and inhibition of pro-inflammatory substances. In vivo, luteolin reduced increased vascular permeability and was effective in animal models of inflammation after parenteral and oral application. Although luteolin is only a minor component in our nutrition (less than 1 mg/day) epidemiological studies indicate that it has the potential to protect from diseases associated with inflammatory processes such as cardiovascular disease. Luteolin often occurs in the form of glycosides in plants, but these are cleaved and the aglycones are conjugated and metabolized after nutritional uptake which has to be considered when evaluating in vitro studies. Some data for oral and topical bioavailability exist, but more quantitative research in this field is needed to evaluate the physiological and therapeutical potential of luteolin.

428 citations

Journal ArticleDOI
TL;DR: Luteolin displays specific anti-inflammatory and anti-carcinogenic effects, which can only partly be explained by its anti-oxidant and free radical scavenging capacities.
Abstract: Luteolin is a flavonoid which is part of our daily nutrition in relatively low amounts (less than 1 mg/day). Nevertheless, some epidemiological studies suggest an inverse correlation between luteolin intake and the risk of some cancer types. Luteolin displays specific anti-inflammatory and anti-carcinogenic effects, which can only partly be explained by its anti-oxidant and free radical scavenging capacities. Luteolin can delay or block the development of cancer cells in vitro and in vivo by protection from carcinogenic stimuli, by inhibition of tumor cell proliferation, by induction of cell cycle arrest and by induction of apoptosis via intrinsic and extrinsic signaling pathways. When compared to other flavonoids, luteolin was usually among the most effective ones, inhibiting tumor cell proliferation with IC 50 values between 3 and 50 µM in vitro and in vivo by 5 to 10 mg/kg i.p., intragastric application of 0.1–0.3 mg/kg/d, or as food additive in concentrations of 50 to 200 ppm. Luteolin has been shown to penetrate into human skin, making it also a candidate for the prevention and treatment of skin cancer.

300 citations

Journal ArticleDOI
14 Feb 2002-Oncogene
TL;DR: In vivo, hyperforin inhibited the growth of autologous MT-450 breast carcinoma in immunocompetent Wistar rats to a similar extent as the cytotoxic drug paclitaxel, without any signs of acute toxicity.
Abstract: Inhibition of tumour cell growth by hyperforin, a novel anticancer drug from St. John's wort that acts by induction of apoptosis

247 citations

Journal ArticleDOI
TL;DR: It is concluded that due to their antimicrobial effects some of the plant extracts may be used for the topical treatment of skin disorders like acne vulgaris and seborrhoic eczema.

239 citations


Cited by
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Journal ArticleDOI
TL;DR: The ability to prospectively identify tumorigenic cancer cells will facilitate the elucidation of pathways that regulate their growth and survival and strategies designed to target this population may lead to more effective therapies.
Abstract: Breast cancer is the most common malignancy in United States women, accounting for >40,000 deaths each year. These breast tumors are comprised of phenotypically diverse populations of breast cancer cells. Using a model in which human breast cancer cells were grown in immunocompromised mice, we found that only a minority of breast cancer cells had the ability to form new tumors. We were able to distinguish the tumorigenic (tumor initiating) from the nontumorigenic cancer cells based on cell surface marker expression. We prospectively identified and isolated the tumorigenic cells as CD44+CD24−/lowLineage− in eight of nine patients. As few as 100 cells with this phenotype were able to form tumors in mice, whereas tens of thousands of cells with alternate phenotypes failed to form tumors. The tumorigenic subpopulation could be serially passaged: each time cells within this population generated new tumors containing additional CD44+CD24−/lowLineage− tumorigenic cells as well as the phenotypically diverse mixed populations of nontumorigenic cells present in the initial tumor. The ability to prospectively identify tumorigenic cancer cells will facilitate the elucidation of pathways that regulate their growth and survival. Furthermore, because these cells drive tumor development, strategies designed to target this population may lead to more effective therapies.

10,058 citations

Journal ArticleDOI
TL;DR: This work highlights a key role for interactions between hyaluronan and tumour cells in several aspects of malignancy and indicates the possibility of new therapeutic strategies.
Abstract: Hyaluronan is an extracellular and cell-surface-associated polysaccharide that is traditionally regarded as a biological 'goo' that participates in lubricating joints or holding together gel-like connective tissues. Although these are common physiological roles of hyaluronan in adult organisms, hyaluronan also functions as a microenvironmental cue that co-regulates cell behaviour during embryonic development, healing processes, inflammation and tumour development. Recent work highlights a key role for interactions between hyaluronan and tumour cells in several aspects of malignancy and indicates the possibility of new therapeutic strategies.

1,910 citations

Journal ArticleDOI
TL;DR: However, there are emerging data suggesting that, depending on the model of apoptosis, the loss of deltapsi(m) may not be an early requirement for apoptosis but on the contrary may be a consequence of the apoptotic-signaling pathway as mentioned in this paper.
Abstract: Mitochondrial dysfunction has been shown to participate in the induction of apoptosis and has even been suggested to be central to the apoptotic pathway. Indeed, opening of the mitochondrial permeability transition pore has been demonstrated to induce depolarization of the transmembrane potential (deltapsi(m)), release of apoptogenic factors and loss of oxidative phosphorylation. In some apoptotic systems, loss of deltapsi(m) may be an early event in the apoptotic process. However, there are emerging data suggesting that, depending on the model of apoptosis, the loss of deltapsi(m) may not be an early requirement for apoptosis, but on the contrary may be a consequence of the apoptotic-signaling pathway. Furthermore, to add to these conflicting data, loss of deltapsi(m) has been demonstrated to not be required for cytochrome c release, whereas release of apoptosis inducing factor AIF is dependent upon disruption of deltapsi(m) early in the apoptotic pathway. Together, the existing literature suggests that depending on the cell system under investigation and the apoptotic stimuli used, dissipation of deltapsi(m) may or may not be an early event in the apoptotic pathway. Discrepancies in this area of apoptosis research may be attributed to the fluorochromes used to detect deltapsi(m). Differential degrees of sensitivity of these fluorochromes exist, and there are also important factors that contribute to their ability to accurately discriminate changes in deltapsi(m).

1,244 citations

Journal ArticleDOI
TL;DR: This review paper proposes a model which elucidates how these molecular pathways intersect with one another, and how various internal and external factors can disrupt these pathways, ultimately leading to a disruption in collagen and elastin networks.
Abstract: Collagen and elastin networks make up the majority of the extracellular matrix in many organs, such as the skin. The mechanisms which are involved in the maintenance of homeostatic equilibrium of these networks are numerous, involving the regulation of genetic expression, growth factor secretion, signalling pathways, secondary messaging systems, and ion channel activity. However, many factors are capable of disrupting these pathways, which leads to an imbalance of homeostatic equilibrium. Ultimately, this leads to changes in the physical nature of skin, both functionally and cosmetically. Although various factors have been identified, including carcinogenesis, ultraviolet exposure, and mechanical stretching of skin, it was discovered that many of them affect similar components of regulatory pathways, such as fibroblasts, lysyl oxidase, and fibronectin. Additionally, it was discovered that the various regulatory pathways intersect with each other at various stages instead of working independently of each other. This review paper proposes a model which elucidates how these molecular pathways intersect with one another, and how various internal and external factors can disrupt these pathways, ultimately leading to a disruption in collagen and elastin networks.

1,230 citations

Patent
Austin L. Gurney1
13 Jun 2006
TL;DR: In this article, the authors presented gene expression profiles associated with solid tumor stem cells, as well as novel stem cell cancer markers useful for the diagnosis, characterization, and treatment of the stem cells.
Abstract: The present invention relates to compositions and methods for treating, characterizing, and diagnosing cancer. In particular, the present invention provides gene expression profiles associated with solid tumor stem cells, as well as novel stem cell cancer markers useful for the diagnosis, characterization, and treatment of solid tumor stem cells.

893 citations