Nettle Leaves
Modulatory effect of Urtica dioica L. (Urticaceae) leaf extract on biotransformation enzyme systems, antioxidant enzymes, lactate dehydrogenase and lipid peroxidation in mice
1: Phytomedicine. 2003;10(5):405-15.
Modulatory effect of Urtica dioica L. (Urticaceae) leaf extract on biotransformation enzyme systems, antioxidant enzymes, lactate dehydrogenase and lipid peroxidation in mice.
Ondokuz Mayis University, The Faculty of Arts and Sciences, Department of Chemistry, Kurupelit, Samsun-Turkey. tevfikoz@omu.edu.tr
The effects of two doses (50 and 100 mg/kg body wt given orally for 14 days) of an ethanol-water (80%-20%) extract of Urtica dioica L. and butylated hydroxyanisole (BHA) were investigated, for phase I and phase II enzymes, antioxidant enzymes, lactate dehydrogenase, lipid peroxidation and sulfhydryl groups in the liver of Swiss albino mice (8-9 weeks old). A modulatory effect of two doses and BHA was also observed for the activities of glutathione S-transferase, DT-diaphorase, superoxide dismutase and catalase in the kidney, lung and forestomach, as compared with the control group. The activities of cytochrome b5 (cyt b5), NADH-cytochrome b5 reductase (cyt b5 R), glutathione S-transferase (GST), DT-diaphorase (DTD), glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD) and catalase (CAT) showed a significant increase in the liver at both dose levels of extract. Both extract-treated showed significantly lower activity of cytochrome P450 (cyt P450), lactate dehydrogenase (LDH), NADPH-cytochrome P450 reductase (cyt P450 R), total sulfhydryl groups (T-SH), nonprotein sulfhydryl groups (NP-SH) and protein-bound sulfhydryl groups (PB-SH). BHA-treated Swiss albino mice showed a notable increase in levels of cyt b5, DTD, T-SH, PB-SH, GPx, GR, and SOD in the liver while, LDH, cyt P450, cyt P450 R, Cyt b5 R, GST, NP-SH, and CAT levels were reduced significantly as compared to control values. The extract was effective in inducing GST, DTD, SOD and CAT activity in the forestomach and SOD and CAT activity in the lung at both dose levels. BHA-treated Swiss albino mice induced DTD, GST and all antioxidative parameters in the kidney, lung and forestomach.
PMID: 12834006 [PubMed - indexed for MEDLINE]
Immunosuppressant effect of IDS 30, a stinging nettle leaf extract, on myeloid dendritic cells in vitro
1: J Rheumatol. 2002 Apr;29(4):659-66
Comment in:
J Rheumatol. 2002 Apr;29(4):656-8.
Immunosuppressant effect of IDS 30, a stinging nettle leaf extract, on myeloid dendritic cells in vitro.
Strathmann Biotec GmbH, Hamburg, Germany.
OBJECTIVE: Dendritic cells are important antigen presenting cells that play a role in the initiation of rheumatoid arthritis (RA). The stinging nettle leaf extract IDS 30 (Hox alpha) has been recommended for adjuvant therapy of rheumatic diseases. We investigated the immunomodulating effect of IDS 30 extract on the maturation of hematopoietic dendritic cells. METHODS: Human dendritic cells were generated from peripheral blood mononuclear cells cultured in granulocyte macrophage-colony stimulating factor and interleukin 4 (IL-4). Dendritic cell maturation was induced by keyhole limped hemocyanin (KLH). Dendritic cell phenotype was characterized by flow cytometric analysis; dendritic cell cytokine production was measured by ELISA. The ability of dendritic cells to activate naive autologous T cells was evaluated by mixed leukocyte reaction. RESULTS: IDS 30 prevented the maturation of dendritic cells, but did not affect their viability. IDS 30 reduced the expression of CD83 and CD86. It increased the expression of chemokine receptor 5 and CD36 in a dose dependent manner. The secretion of tumor necrosis factor-alpha was reduced. Application of IDS 30 to dendritic cells in culture caused a high endocytosis of dextran and a low capacity to stimulate T cell proliferation. CONCLUSION: Our in vitro results showed the suppressive effect of IDS 30 on the maturation of human myeloid dendritic cells, leading to reduced induction of primary T cell responses. This may contribute to the therapeutic effect of IDS 30 on T cell mediated inflammatory diseases like RA.
PMID: 11950004 [PubMed - indexed for MEDLINE]
Antirheumatic effect of IDS 23, a stinging nettle leaf extract, on in vitro expression of T helper cytokines.
1: J Rheumatol. 1999 Dec;26(12):2517-22.
Antirheumatic effect of IDS 23, a stinging nettle leaf extract, on in vitro expression of T helper cytokines.
Strathmann Research GmbH, Hamburg, Germany.
OBJECTIVE: Stinging nettle leaf extracts are registered in Germany for adjuvant therapy of rheumatic diseases. In a whole blood culture system the nettle extract IDS 23 (Rheuma-Hek) inhibited lipopolysaccharide stimulated monocyte cytokine expression, indicating an immunomodulating effect. We investigated the immunomodulating effects of IDS 23 on phytohemagglutinin (PHA) stimulated peripheral blood mononuclear cells (PBMC) in vitro. METHODS: Using commercial immunoassays the distinct cytokine patterns of Th1 and Th2 cells were determined. Interleukin 2 (IL-2) and interferon-gamma (IFN-gamma) mRNA expression was evaluated by reverse transcription-polymerase chain reaction (RT-PCR) with PHA stimulated PBMC. RESULTS: IDS 23 inhibited PHA stimulated production of Th1-specific IL-2 and IFN-gamma in PBMC culture (n = 10) in a dose dependent manner up to 50+/-32% and 77+/-14%, respectively. In contrast, IDS 23 stimulated the secretion of Th2-specific IL-4. The dose dependent inhibiting effect on IL-2 and IFN-gamma expression was also detected with RT-PCR, while the amount of actin-specific mRNA transcript was not modified by IDS 23. CONCLUSION: Our results suggest the effective ingredient of IDS 23 acts by mediating a switch in T helper cell derived cytokine patterns. IDS 23 may inhibit the inflammatory cascade in autoimmune diseases like rheumatoid arthritis.
PMID: 10606356 [PubMed - indexed for MEDLINE]
Plant extracts from stinging nettle (Urtica dioica), an antirheumatic remedy, inhibit the proinflammatory transcription factor NF-kappaB
: FEBS Lett. 1999 Jan 8;442(1):89-94
Plant extracts from stinging nettle (Urtica dioica), an antirheumatic remedy, inhibit the proinflammatory transcription factor NF-kappaB.
Department of Internal Medicine I, Medical Clinics, University of Tubingen, Germany.
Activation of transcription factor NF-kappaB is elevated in several chronic inflammatory diseases and is responsible for the enhanced expression of many proinflammatory gene products. Extracts from leaves of stinging nettle (Urtica dioica) are used as antiinflammatory remedies in rheumatoid arthritis. Standardized preparations of these extracts (IDS23) suppress cytokine production, but their mode of action remains unclear. Here we demonstrate that treatment of different cells with IDS23 potently inhibits NF-kappaB activation. An inhibitory effect was observed in response to several stimuli, suggesting that IDS23 suppressed a common NF-kappaB pathway. Inhibition of NF-kappaB activation by IDS23 was not mediated by a direct modification of DNA binding, but rather by preventing degradation of its inhibitory subunit IkappaB-alpha. Our results suggests that part of the antiinflammatory effect of Urtica extract may be ascribed to its inhibitory effect on NF-kappaB activation.
PMID: 9923611 [PubMed - indexed for MEDLINE]




