Delayed blockade of the kinin B1 receptor reduces renal inflammation and fibrosis in obstructive nephropathy.

Renal fibrosis is the common histological feature of advanced glomerular and tubulointerstitial disease leading to end-stage renal disease (ESRD). However, specific antifibrotic therapies to slow down the evolution to ESRD are still absent. Because persistent inflammation is a key event in the development of fibrosis, we hypothesized that the proinflammatory kinin B1 receptor (B1R) could be such a new target. Here we show that, in the unilateral ureteral obstruction model of renal fibrosis, the B1R is overexpressed and that delayed treatment with an orally active nonpeptide B1R antagonist blocks macrophage infiltration, leading to a reversal of the level of renal fibrosis. In vivo bone marrow transplantation studies as well as in vitro studies on renal cells show that part of this antifibrotic mechanism of B1R blockade involves a direct effect on resident renal cells by inhibiting chemokine CCL2 and CCL7 expression. These findings suggest that blocking the B1R is a promising antifibrotic therapy.

The Ask-Upmark kidney: a curable cause of hypertension in young patients.

We are reporting a case of arterial hypertension in a young woman who had an atrophic kidney with a cortical groove and histological features of the Ask-Upmark kidney. Her hypertension was renin dependent and the patient was cured following nephrectomy. Controversy on the pathogenesis of this clinical entity is briefly reviewed.

Flavonoids: structural requirements for antiproliferative activity on breast cancer cells.

Several classes of flavonoids (flavones, flavanones, 2'-hydroxychalcones and flavan-4-ols) having a variety of substituents on A ring were investigated for their antiproliferative activity against MCF-7 human breast cancer cells. Structure-activity relationships of these compounds were discussed. 2'-hydroxychalcones and methoxylated flavanones were found to be potent inhibitors of MCF-7 cells growth whereas flavones and flavan-4-ols appeared to be weak inhibitory agents except 7,8-dihydroxyflavone.

Detection of Sugarcane yellow leaf virus in Quarantine and Production of Virus-free Sugarcane by Apical Meristem Culture.

Sugarcane yellow leaf virus (SCYLV) was detected for the first time in 1996 in the Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD) sugarcane quarantine at Montpellier by reverse transcription-polymerase chain reaction (RT-PCR) in varieties from Brazil, Florida, Mauritius, and Réunion. Between 1997 and 2000, the virus was found by RT-PCR and/or tissue-blot immunoassay (TBIA) in additional varieties from Barbados, Cuba, Guadeloupe, Indonesia, Malaysia, Philippines, Puerto Rico, and Taiwan, suggesting a worldwide distribution of the pathogen. An excellent correlation was observed between results obtained for the two diagnostic techniques. However, even though only a few false negative results were obtained by either technique, both are now used to detect SCYLV in CIRAD's sugarcane quarantine in Montpellier. The pathogen was detected by TBIA or RT-PCR in all leaves of sugarcane foliage, but the highest percentage of infected vascular bundles was found in the top leaves. The long hot water treatment (soaking of cuttings in water at 25°C for 2 days and then at 50°C for 3 h) was ineffective in eliminating SCYLV from infected plants. Sugarcane varieties from various origins were grown in vitro by apical bud culture and apical meristem culture, and the latter proved to be the most effective method for producing SCYLV-free plants.

Ursolic acid triggers calcium-dependent apoptosis in human Daudi cells.

Ursolic acid (UA) is a pentacyclic triterpenoid compound which occurs naturally in a large variety of vegetarian foods, medicinal herbs and plants. In the present study, ursolic acid was found to decrease cell viability in human lymphoma Daudi cells in a dose-dependent manner. UA also induced morphological changes in cells as well as loss of membrane asymmetry, DNA fragmentation and nuclei condensation, indicating that the mechanism by which UA induced cell death was through apoptosis. Treatment with UA increased intracellular Ca2+ levels. Use of Ca2+ channel inhibitors like verapamil blocked this Ca2+ influx and also the triggering of apoptosis. We hypothesized that the binding of UA to glucocorticoid receptors and the Ca2+ currents induced constituted the first steps of apoptosis.

Lipiodol ultra-fluid: an antitumor agent-in vitro study.

Lipiodol Ultra-Fluid (LUF), a contrast medium for the diagnosis and treatment of hepatocellular carcinoma (HCC), is used by hepatic intra-arterial infusion. Hepatoma cells are capable of active uptake of LUF and retaining it for prolonged periods of time. These characteristics have important therapeutic potential for the targeting of anticancer drugs and have lead us to form an intratumoral diffuser. But, before in vivo studies, we have investigated in vitro LUF effects on various cell species in order to explain and refine the lipiodol chemotherapy. The antiproliferative and cytotoxic effects of LUF on HepG2 (human hepatoma cells), MCF-7 (human breast cancer cells) murine macrophages and human hepatocytes, were assessed by Trypan blue exclusion and lactico-dehydrogenase extracellular tests. We demonstrated the dose and time-dependent antiproliferative and cytotoxic activities of LUF on cells. Cytotoxicity was different according to cells species, whether or not they had cancerous characteristics and phagocytosis function: this cytotoxicity was very significant on macrophages and was greater for cancerous cells than for human hepatocytes in primary culture. We showed in vitro, for the first time, that LUF was an antiproliferative and cytotoxic agent, because of its active uptake and selective retention which lead to cellular death due to necrosis by lipoperoxidation increase.

Inhibitory effect of curcuminoids on MCF-7 cell proliferation and structure-activity relationships.

Curcumin, demethoxycurcumin and bisdemethoxycurcumin are the yellow coloring phenolic compounds isolated from the spice turmeric. This study was part of a program correlating the biological activity and molecular structure of antitumor agents; the effect of these curcuminoids and cyclocurcumin (Cyclocur) was examined on the proliferation of MCF-7 human breast tumor cells. Curcuminoids appeared to be potent inhibitors, whereas Cyclocur was less inhibitory. To contribute to our understanding of the mechanism of antiproliferative activity of curcumin, cell cycle analysis was performed by propidium iodide staining and a flow cytometry technique. Curcumin exerts a cytostatic effect at G2/M which explains its antiproliferative activity. The presence of the diketone moiety in the curcumin molecule seems to be essential for the inhibitory activity.

Inhibitory effect of ursolic acid on B16 proliferation through cell cycle arrest.

The effects of ursolic acid on the proliferation of B16, a mouse melanoma cell line, were studied. During investigations of the anti-proliferative effects of this triterpene, we observed that MTT colorimetric and colony forming assays show that ursolic acid is a potent inhibitor of B16 cell growth. Cell cycle analysis was performed by propidium iodide staining and flow cytometry technique. This triterpene exerts an early effect on cell cycle at G1, which explains its anti-proliferative activity. These results suggest that alterations in cell cycle phase redistribution of B16, by ursolic acid, may significantly influence the proliferation of B16, melanoma cells.

MCF-7 cell cycle arrested at G1 through ursolic acid, and increased reduction of tetrazolium salts.

The effect of ursolic acid on the proliferation of MCF-7 human breast tumor cells was studied. During investigations of the anti-proliferative effects of this triterpene, we observed a clear difference between MTT colorimetric assay and direct cell counting, particularly 24 h after drug treatment. The MTT assay showed a stimulation of formazan production in the first 24 h exposure of cells to drug. The maximum stimulation was obtained with 15 and 20 microM of ursolic acid (about 30 - 40% of increase with respect to control); however, the number of cells was not increased as revealed by direct cell counting. Ursolic acid is a potent inhibitor of MCF-7 cell proliferation. This triterpene exhibits both cytostatic and cytotoxic activity. It exerts an early cytostatic effect at G1 followed by cell death. Cell cycle analysis is performed by propidium iodide staining and flow cytometry technique. These results suggest that alterations in cell cycle phase redistribution of MCF-7 human breast cancer, by ursolic acid, may significantly influence MTT reduction to formazan.

Stimulated human gastric tumor cells (HGT) fail to synthesize eicosanoids.

HGT cells are a human gastric tumor cell line. Preliminary data have shown that HGT cells incorporate exogenous arachidonic acid (AA) in their membrane lipids. However, we found that HGT cells are unable to produce significant amounts of AA metabolites after stimulation with calcium ionophore A23187. Furthermore, no lipoxygenase activity was detected in crude HGT cell extracts by employing an assay monitoring the in vitro utilization of linoleic acid. The meaning of these results is discussed in respect of the role of eicosanoids during cell proliferation.

Quercetin 3-[triacetylarabinosyl(1-->6)galactoside] and chromones from Calluna vulgaris.

The new quercetin 3-[2,3,4-triacetyl-alpha-L-arabinopyranosyl (1-->6)-beta-D-galactoside] has been isolated along with 5,7-dihydroxychromone and 5,7-dihydroxychromone 7-beta-D-glucoside from fresh flowers of Calluna vulgaris. Structural elucidation of these natural products was achieved mainly by 1H and 13C NMR.

Effects of Ursolic Acid and its Analogues on Soybean 15-Lipoxygenase Activity and the Proliferation Rate of A human Gastric Tumour Cell Line.

The authors have previously isolated and purified ursolic acid from heather flowers (Calluna vulgarts). This terpene was found to inhibit HL-60 leukaemic cell proliferation and arachidonic acid oxidative metabolism in various cell species. The effects of ursolic acid and its analogues on soybean 15-lipoxygenase activity and on the proliferation of a human gastric tumour cell line (HGT), have been assessed. These triterpenes inhibited soybean 15-lipoxygenase at its optimal activity (pH 9). The proliferation ofHGT was decreased in a dose-dependent manner. At 20 muM the rank order is: ursolic acid > uvaol > oleanolic acid > methyl ursolate. The carboxylic group at the C(28) position of ursolic acid appears to be implicated in the inhibition of both lipoxygenase activity and cell proliferation. Thus methylation of this group decreases these two inhibitory properties. Oleanolic acid, which differs by the position of one methyl group (C(20) instead of C(19)) is less inhibitory than ursolic acid. The lipophilicity of the terpene is also implicated since uvaol appears to be more inhibitory than methyl ursolate.

Inhibition of lipoxygenase activity and HL60 leukemic cell proliferation by ursolic acid isolated from heather flowers (Calluna vulgaris).

A compound was isolated and purified from heather flowers (Calluna vulgaris) based on its ability to inhibit lipoxygenase activity. This molecule was characterized as ursolic acid by GC-MS. Ursolic acid was found to be an inhibitor of both potato tuber 5-lipoxygenase and soybean 15-lipoxygenase with IC50 values of 0.3 mM. Ursolic acid also inhibits lipoxygenase activity in mouse peritoneal macrophages at 1 microM and HL60 leukemic cells growth (IC50 = 0.85 microM) as well as their DNA synthesis (IC50 = 1 microM). The possible role of lipoxygenase inhibition in the proliferation of leukemic cells is discussed.

Characterization of ursolic acid as a lipoxygenase and cyclooxygenase inhibitor using macrophages, platelets and differentiated HL60 leukemic cells.

A new property of ursolic acid, lipoxygenase and cyclooxygenase inhibition, has been described in an acetone-extract of heather flowers (Calluna vulgaris) which could help explain the anti-inflammatory characteristics of this plant. In mouse peritoneal macrophages, human platelets and differentiated HL60 leukemic cells, ursolic acid, at 1 microM, blocks arachidonate metabolism.

A Calluna vulgaris extract 5-lipoxygenase inhibitor shows potent antiproliferative effects on human leukemia HL-60 cells.

A water-Calluna vulgaris extract (water-CVE) was found to be a relatively specific arachidonate 5-lipoxygenase inhibitor and showed potent anti-proliferative effects on human leukemic HL60 cells. Water-CVE completely inhibited potato 5-lipoxygenase activity at 250 micrograms/ml, partially inhibited soybean 15-lipoxygenase at pH 7.4 and had no effect either on this 15-lipoxygenase at its optimal activity pH (pH 9) or on Lupinus albus 5-, 8-, 15-lipoxygenase. In culture, the proliferation and DNA synthesis of HL60 cells were decreased by water-CVE in a dose-dependent manner with an IC50 of 200 micrograms/ml at day 4. This effect of water-CVE is related to the starting density of HL60 cells. These results suggest that arachidonate 5-lipoxygenase metabolites and/or leukotrienes could play an essential role in cellular functions of leukemic cells and may explain the success of the use of Calluna vulgaris as tea and baths in folk medicine.

Induction of ovulation in polycystic ovary syndrome with a combination of a luteinizing hormone-releasing hormone analog and exogenous gonadotropins.

Eight clomiphene citrate (150 mg/day for 5 days)-resistant anovulatory women with polycystic ovary were included in this study. A luteinizing hormone-releasing hormone (LH-RH) analog, D-Trp-6-LH-RH, 100 micrograms subcutaneous-per day, induced a hypogonadotropic state within varying periods but at most within 3 weeks, after an initial flare-up effect characterized by slight increase in ovarian size in four patients and in the other four by cysts that disappeared rapidly. On the 28th day or 15 to 20 days after menstruation for subsequent cycles, during maintenance of D-Trp-6-LH-RH therapy, a usual gonadotropin regimen was carried out in 33 cycles. Human menopausal gonadotropins obtained follicular maturation in all cycles. However, there was never the growth of a single dominant follicle but always of several follicles. Human chorionic gonadotropin then induced ovulation in 31 cycles (94%). Luteal phase was normal in 28 and inadequate in 3 of the 31 ovulatory cycles. Hyperstimulation, generally mild to moderate but rather severe in 2 cycles, was constant. Five pregnancies were obtained. The overall pregnancy rate was 15% per cycle and 17.8% per normoovulatory cycle. This study showed that an associated treatment with an LH-RH analog enables gonadotropins to achieve ovulation regularly with an encouraging number of pregnancies but at a risk of hyperstimulation.