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PubMed2003

Production of tobacco aroma from lutein. Specific role of the microorganisms involved in the process.

A mixed culture formed by Bacillus sp. and Geotrichum sp. produced tobacco aroma compounds from the carotenoid lutein through the formation of the intermediate beta-ionone. Both microorganisms can grow independently in a medium supplemented with lutein, but only Geotrichum produces beta-ionone. This intermediate was incorporated by the bacilli, converted to aroma and this product excreted to the culture medium. Bacillus sp. did not utilize beta-ionone for growth but modified it. We conclude that, in the bioconversion of lutein to products with tobacco aroma, Geotrichum sp. is involved in carotenoid oxidation to produce beta-ionone and Bacillus sp. is responsible for the norisoprenoid reduction to produce 7,8-dihydro-beta-ionone and 7,8-dihydro-beta-ionol.

Bacillus↗

PubMed2006

Lutein sequestration and furanocoumarin metabolism in parsnip webworms under different ultraviolet light regimes in the montane west.

Both biotic and abiotic selection pressures can contribute to geographic variation in allelochemical production in plants. We examined furanocoumarin production in western North American populations of Heracleum lanatum and Pastinaca sativa that, at different latitudes and altitudes, experience different ultraviolet (UV) light regimes. Total furanocoumarins and linear furanocoumarins of fruits were negatively correlated with UV irradiance, whereas amounts of angular furanocoumarins, which are generally less phototoxic, were not. Another factor potentially influencing furanocoumarin production is the presence of the parsnip webworm Depressaria pastinacella, (Lepidoptera: Oecophoridae), an herbivore that feeds on reproductive structures of both plant species. These insects sequester lutein from their host plants; this carotenoid acts to ameliorate furanocoumarin toxicity. Although the concentration of lutein in fruits did not vary with UV irradiance, lutein sequestration by sixth instars was positively correlated with UV irradiance. Webworm populations are variably infested with the polyembryonic webworm parasitoid Copidosoma sosares Walker (Hymenoptera: Encyrtidae). H. lanatum fruits from populations with webworms parasitized by C. sosares had lower concentrations of furanocoumarins, with the exception of sphondin, than fruits from plants infested with webworms free from parasitism. Lower levels of these furanocoumarins may reduce negative effects on the fitness of this parasitoid. In contrast with the variation in furanocoumarin content, the ability of webworms to metabolize furanocoumarins by cytochrome P450 did not differ significantly among populations from New Mexico to Alberta.

Animals↗

PubMed1985

Luteinizing hormone-releasing hormone agonist and uterine leiomyoma: a pilot study.

Ten women with 12 uterine leiomyomas ranging from 7.5 to 420 cc (mean, 112.6 +/- 39.4) were treated with subcutaneous injections of the luteinizing hormone-releasing hormone agonist buserelin, 200 micrograms three times daily for 1 week and then 500 micrograms daily for the rest of the 6-month treatment period. Following initial stimulation the pituitary ovarian axis was suppressed after 3 weeks of treatment with mean serum estradiol ranging between 17 and 36 pg/ml. Seven uterine leiomyomas had a marked regression in size following treatment with luteinizing hormone-releasing hormone agonist; two were undetectable and the volume of the other five diminished by an average of 80%. One tumor did not respond to treatment, two regressed by 25%, and two, following an initial reduction of 65% and 50%, reenlarged during the last 2 months of treatment to 75% and 100% respectively of their initial volume. Luteinizing hormone-releasing hormone agonist is the first medication demonstrated effective in reducing the size of uterine myomas.

Adult↗

PubMed1983

Discordant regulation by luteinizing hormone of ornithine decarboxylase activity and testosterone production in isolated rat testicular cells in vitro.

Possible functional relationship between luteinizing hormone-stimulated ornithine decarboxylase and testosterone production was examined in rat testicular interstitial cells in vitro. Although luteinizing hormone enhanced both ornithine decarboxylase activity and testosterone production at a similar physiological dose range, we found dissociation in the two responses in terms of their temporal aspect and the way they were affected by an irreversible inhibitor of ornithine decarboxylase, alpha-difluoromethylornithine, and protein synthesis inhibitor cycloheximide. The results suggest that there appears to be no causal coupling between luteinizing hormone-stimulated enzyme activity and testicular steroidogenesis.

Animals↗

PubMed1975

Preparation of high-quality iodine-125-labelled pituitary luteinizing hormone for radioimmunoassay.

High quality pituitary luteinizing hormone labelled with 125-I was obtained after separating out the more heavily iodinated fractions, through starch gel electrophoresis, using the cathodal component (Fraction 1) which was further purified on Sephadex G-100, giving an almost pure 125-I-labelled luteinizing hormone preparation, presenting excellent immunoreactivity and low levels of damage on incubation in plasma. The quality control of the steps of the technique was done with plasma-coated talc (200 mg) which compared favorably, as far as being an indication of intact labelled luteinizing hormone, with the more time-consuming chromatoelectrophoresis.

Animals↗

PubMed1983

Action of nitroguanidinated luteinizing hormone on different rat gonadal tissues.

The biological activities of nitroguanidinated derivatives prepared from ovine or porcine luteinizing hormone were investigated using rat Leydig cells and pseudopregnant rat ovaries. In these tissues nitroguanidyl ovine luteinizing hormone (NGoLH) or nitroguanidyl porcine luteinizing hormone (NGpLH) were unable to stimulate adenylate cyclase or steroidogenesis but were able to inhibit the binding of ovine or porcine native LH to their specific receptors. When added to incubations of isolated Leydig cells or pseudopregnant ovary slices, NGoLH as well as NGpLH inhibited the stimulating action of native LH on adenylate cyclase or steroidogenesis. However, these derivatives had no inhibiting action on the stimulation of adenylate cyclase and steroidogenesis induced in the Leydig cells by choleratoxin or on the stimulation of testosterone production induced by 8-bromo-cyclic AMP. Since NGpLH (which does not contain lysine residues or free alpha-amino groups in the beta-subunit) exhibits the same antagonist action as NGoLH, we conclude that the nitroguanidination of the alpha-subunit is sufficient to endow the derivative with antihormone properties.

Adenylyl Cyclases↗

PubMed1991

Luteinization of porcine thecal cells in vitro.

The objective of this study was to determine the requirements for the functional luteinization of porcine thecal cells in vitro. In serum-free incubations with luteinizing hormone (LH) (250 ng/ml) androstenedione concentrations increased up to 14 h, after which time no further accumulation occurred; progesterone accumulation was low, and did not increase after 4 h. In the presence of 1% fetal bovine serum and LH, androstenedione production declined, but progesterone production per day increased over a 4-day period, while cellular protein remained constant. LH was required for both the induction and maintenance of elevated progesterone production. Insulin (maximal response at 500 ng/ml) in the presence of 1% serum enhanced the response to LH, causing a dramatic increase in progesterone production, an effect which became greater with time in culture. Dose-response curves for insulin and insulin-like growth factor I (IGF-I) were parallel, but IGF-I was approximately 23-fold more potent than insulin, suggesting that insulin was acting through IGF-I receptors. Our results show that porcine thecal cells, in the presence of LH, insulin or IGF-I, and 1% serum, undergo functional luteinization in vitro, such that androstenedione production declines, and the rate of progesterone production increases with time in culture.

Androstenedione↗

PubMed1994

Simple determination of retinol, alpha-tocopherol and carotenoids (lutein, all-trans-lycopene, alpha- and beta-carotenes) in human plasma by isocratic liquid chromatography.

Retinol, alpha-tocopherol, lutein, all-trans-lycopene, and alpha- and beta-carotenes can be simultaneously determined in human plasma by reversed-phase liquid chromatography with a programmable and variable UV wavelength detector. Plasma (200 microliters) is deproteinized with 200 microliters of ethanol containing retinyl acetate, as internal standard, then extracted with 1.0 ml of n-hexane-2,6-di-tert.-butyl-p-cresol (BHT). The organic layer is removed and evaporated and the residue is dissolved in 100 microliters of a mixture of acetonitrile-tetrahydrofuran-methanol (68:22:7, v/v/v). Aliquots (15 microliters) are injected onto a 250 x 4.6 mm I.D. column of Nucleosil 100-5 C18 with a pre-column of Lichrosorb RP-18, 7 microns, 15 x 3.2 mm I.D. A mobile phase of acetonitrile-tetrahydrofuran-methanol (68:22:7, v/v/v), adjusted to 100 (v/v) with 1% ammonium acetate, at a flow-rate of 1.5 ml/min is used. Usual run time is 15 min. Retinol and retinyl acetate are monitored at 325 nm, tocopherol at 290 nm, lycopene at 470 nm, lutein and alpha- and beta-carotenes at 450 nm. The intra-batch coefficients of variation (C.V.) were 2.5, 2.2, 2.4, 5.8, 5.1 and 4.7% for retinol, alpha-tocopherol, lutein, trans-lycopene, alpha- and beta-carotenes, respectively. The inter-batch C.V.s of experiments performed on 30 different days over 12 weeks were 5.7, 3.9, 4.5, 10.9, 11.3 and 10.5%, respectively.

Carotenoids↗

PubMed2006

Influence of tumor necrosis factor-alpha on estradiol, progesterone, insulin-like growth factor-II, and insulin-like growth factor binding protein-1, 2, and 3 in cultured human luteinized granulosa cells.

OBJECTIVE: The objective was to investigate the influence of tumor necrosis factor (TNF)-alpha on estradiol, progesterone, insulin-like growth factor (IGF)-II, and insulin-like growth factor binding protein (IGFBP)-1, 2, and 3 in cultured human luteinized granulosa cells. STUDY DESIGN: Human luteinized granulosa cells were obtained from follicular fluid by transvaginal oocyte aspiration from infertile patients undergoing controlled ovarian hyperstimulation (COH) for in vitro fertilization (IVF). The cells were cultured for 72 h with TNF-alpha at concentrations of 1.0, 10.0, and 100.0 ng/ml. The cells not treated with TNF-alpha served as controls. Radioimmunoassay (RIA) and reverse transcription-polymerase chain reaction (RT-PCR) were used to examine the influence of TNF-alpha on estradiol, progesterone, IGF-II, and IGFBP-1, 2, and 3. Results were analyzed using the Kolmogorov-Smirnov test and analysis of variance (ANOVA). Statistical significance was defined as p<0.05. RESULTS: The concentrations of progesterone seemed to decrease as the concentrations of TNF-alpha increased and the concentration of progesterone in the 100.0 ng/ml TNF-alpha group was significantly lower than that in the control and other TNF-alpha groups. The expressions of IGF-II mRNA in the 10.0 and 100.0 ng/ml TNF-alpha groups were significantly lower than that in the control group. The expressions of IGFBP-2 mRNA seemed to be decreased in the 10.0 and 100.0 ng/ml TNF-alpha groups compared with that in the control group, but there were no statistical significances. CONCLUSION: TNF-alpha may play a role as a regulator of human ovarian physiology by modulating the IGF systems in luteinized granulosa cells.

Adult↗

PubMed2003

Significance of mRNA levels of connexin37, connexin43, and connexin45 in luteinized granulosa cells of controlled hyperstimulated follicles.

OBJECTIVE: To evaluate the mRNA levels of connexins in different sizes of luteinized follicles. DESIGN: Semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) to determine the connexin mRNA levels in the granulosa cells of 91 luteinized follicles. SETTING: Academic tertiary care medical center and research unit of university. PATIENT(S): Ninety-one female patients on controlled ovarian hyperstimulation (COH). INTERVENTION(S): Sonoguided aspiration to collect the oocytes and the granulosa cells simultaneously. MAIN OUTCOME MEASURE(S): The RT-PCR data are normalized by comparing the intensity of the connexins to the intensity of internal controls (beta-actin). The follicles are grouped according to the size and the mRNA levels of the connexins. The correlations among the size of the follicles, the outcome of oocytes, and the mRNA levels of the connexins are compared by Fisher's exact test and Mann-Whitney test. RESULT(S): The mRNA levels of the connexins are low in the follicles equal or larger than 5.5 mL. High cx43 levels are linked to good prognosis of oocytes. CONCLUSION(S): The luteinized granulosa cells from the large follicles are relatively quiescent in the connexin mRNA expression. In addition to the volume, the mRNA levels of cx43 may serve as a marker to predict the outcome of oocytes.

Base Sequence↗

PubMed2006

Influence of astaxanthin, zeaxanthin and lutein on DNA damage and repair in UVA-irradiated cells.

In order to gain more knowledge about the antioxidant role of the predominant carotenoids (lutein and zeaxanthin) of the human retina, this study investigated their antioxidant activity and capacity. Astaxanthin was also studied, because its structure is very close to that of lutein and zeaxanthin. The antioxidant activity of these molecules was evaluated using chemiluminescence techniques, with lucigenin and luminol as chemiluminogenic probes for the superoxide radical and hydrogen peroxide, respectively. It was found that all three carotenoids have similar superoxide-scavenging activity. The effect on the reduction of H(2)O(2)-luminol chemiluminescence was present in the following order, zeaxanthin>astaxanthinlutein. Possible antioxidant capacity of these three compounds was sought using a biological system consisting of SK.N.SH human neuroblastoma and rat trachea epithelial cells subjected to oxidative stress from exposure to UVA radiation. In particular, we determined whether these compounds were capable of minimizing DNA damage and influencing the kinetics of DNA repair. DNA damage was assessed using the Comet assay, a rapid and sensitive single-cell gel electrophoresis technique used to detect primary DNA damage in individual cells. Neuroblastoma cells appeared more resistant to oxidative irradiation insult. The presence of carotenoids reduced DNA damage when rat epithelial cells were exposed to UVA radiation for 2min. A different result was obtained in experiments performed on neuroblastoma cells; in this case, the presence of carotenoid during UVA exposition increased the damage. The addition of carotenoids to epithelial cells after 2min of UVA exposition did not seem to improve the kinetics of DNA repair; on the contrary, zeaxanthin (after 60' incubation) and lutein (after 180' incubation) showed a genotoxic effect. The addition of carotenoids to neuroblastoma cells after 30' UVA exposition positively influences the kinetics of DNA repair in the first 15min of incubation. At longer exposition times, while the behaviour measured was not constant, a genotoxic effect was not observed. The data from this study provide additional information on the antioxidant and pro-oxidant activities of the predominant macular pigment carotenoids of the human retina.

Animals↗

PubMed1978

Delayed onset of luteinization as a cause of infertility.

Two groups of infertility patients with regular cycles and apparently normal ovarian function were studied. In group I (n = 28) the infertility could be explained satisfactorily either by tubal occlusion or by infertility of the husband, or the women became pregnant within a few months. In group II (n = 32) no explanation was found for the infertility. Significantly fewer ovulation stigmata were present at laparoscopy in group II than in group I (P less than 0.05). In group I the basal body temperature (BBT) (P less than 0.001) and the plasma progesterone concentrations (P less than 0.05) were significantly elevated on the 1st day following the luteinizing hormone (LH) peak. In group II, THE BBT was slightly elevated on the 1st day following the LH peak (P less than 0.05), but the increase in the plasma progesterone concentrations occurred only on the 2nd day following the LH peak. In four women the onset of the BBT rise followed a normal LH peak with delays respectively, of 3, 4, 4, and 5 days, and in two women no LH peak occurred immediately prior to the onset of the BBT rise. The datings of the endometrial biopsies in these patients were in phase with the onset of the BBT rise but not with the LH peak. It is concluded that anovulation with in situ luteinization may be a rather frequent cause of infertility in regularly cycling women. A hypothesis about the mechanism of anovulation with in situ luteinization is proposed.

Anovulation↗

PubMed1978

Effect of postovulatory treatment with a luteinizing hormone-releasing hormone analog on the plasma level of progesterone in women.

(des-Gly-NH2(10),Pro-ethylamide9) luteinizing hormone-releasing hormone (LH-RH) (100 microgram) was administered subcutaneously once daily for 5 days during the postovulatory period in six women with regular menstrual cycles. Plasma levels of luteinizing hormone, follicle-stimulating hormone, estradiol, and progesterone were measured daily by radioimmunoassay from the ovulatory stage to menses. Suppression of plasma progesterone occurred during the treated luteal phase as compared with that of the control luteal phase. This finding suggests that repetitive, massive, endogenous luteinizing hormone or massive, exogenous, LH-RH itself during the early luteal phase of the cycle may induce functional luteolysis.

Adult↗

PubMed1984

Reversible hypogonadism induced by a luteinizing hormone-releasing hormone (LH-RH) agonist (Buserelin) as a new therapeutic approach for endometriosis.

Ten women with endometriosis (stages I to IV) were treated with twice-daily subcutaneous injections of 200 micrograms of (D-Ser[TBU]6-des-Gly-NH2(10] luteinizing hormone-releasing hormone ethylamide (Buserelin) for 5 days followed by 400 micrograms intranasally three times daily for 25 to 31 weeks. Serum follicle-stimulating hormone levels returned to basal values on the second day of treatment, and serum luteinizing hormone levels progressively decreased to normal within 4 weeks. Serum estradiol decreased below early follicular phase levels within 7 to 30 days and continued to decrease to castrate levels. Light to moderate estrogen withdrawal bleeding was followed by amenorrhea with occasional bleeding or spotting in four women. Abdominal pain and dyspareunia disappeared or were ameliorated after 2 months of treatment. Resorption of endometrial implants was demonstrated by laparoscopy, and endometrial biopsy revealed atrophy or weak proliferation. Ovulation returned within 45 days, and two of four sexually active women became pregnant during cycles 3 and 5. The treatment was well accepted in spite of the expected hot flushes and vaginal dryness. Safety laboratory tests during and after treatment did not reveal any abnormalities. Reversible down-regulation of pituitary/ovarian function using repetitive luteinizing hormone-releasing hormone agonist administration can be a worthwhile approach to medical treatment of endometriosis.

Adolescent↗

PubMed1984

Stimulatory effects of follicle-stimulating hormone and luteinizing hormone upon secretion of progesterone and inhibin activity by cultured infant human ovarian granulosa cells.

Ovarian tissue obtained from three human infants (60, 120, and 210 days of age) was separated into cell types and cultured. Granulosa cells from two of three subjects were viable and grew in culture. The cells had the potential to secrete low levels of progesterone and responded to luteinizing hormone and follicle-stimulating hormone added in culture with greatly enhanced ability to secrete progesterone. Granulosa cells could also secrete inhibin activity in culture and responded to luteinizing hormone and follicle-stimulating hormone with enhanced inhibin secretion. The granulosa cells also had the potential to secrete estrogen in the presence of testosterone. Serum levels of gonadotropin in the human infant are elevated for a period between 1 and 4 months; yet only follicular growth, not luteinization, occurs. It can be concluded that infant human granulosa cells, like adult human granulosa cells, have the potential of responding in vitro to gonadotropin.

Androstenedione↗

PubMed1985

Effect of aromatase inhibition by delta 1-testolactone on basal and luteinizing hormone-releasing hormone-stimulated pituitary and gonadal hormonal function in oligospermic men.

Aromatase inhibition by delta 1-testolactone (TL), 500 mg twice daily for 4 weeks, in nine patients with idiopathic oligospermia lowered circulating estradiol (E2) levels by about 30%, enhanced the secretion of follicle-stimulating hormone (+ 30%), 17-hydroxyprogesterone (17-OHP) (+ 40%), and testosterone (T) (+ 30%), but did not affect serum luteinizing hormone levels. Despite E2 lowering, there was an accumulation of 17-OHP over T, suggesting 17, 20-lyase inhibition. Unexpectedly, administration of TL almost completely deleted the T response to continuous luteinizing hormone-releasing hormone infusion present before TL therapy, despite similar gonadotropin release. Because the 17-OHP response to the luteinizing hormone-releasing hormone infusion was even higher during therapy, the 17,20-lyase lesion seemed aggravated despite substantial reduction of E2 levels. Although the present data suggest that estrogens play a less dominant role in the origin of the late steroidogenetic lesion than previously assumed, the suggestion also arises that TL per se, in addition to its antiestrogenic action, exerts an inhibiting effect on the 17,20-lyase locus, which may obscure the beneficial effect of reducing E2.

Adult↗

PubMed1991

Treatment of uterine leiomyomata with a luteinizing hormone-releasing hormone agonist: the possibility of nonsurgical management in selected perimenopausal women.

OBJECTIVE: To evaluate the efficacy of luteinizing hormone-releasing hormone agonist (LH-RH-a) in the treatment of leiomyomata. DESIGN: A retrospective randomized trial. SETTING: Hospital department of obstetrics and gynecology. PATIENTS: Twenty-five women, ages 36 to 54 years with symptomatic uterine leiomyomata, were divided into two groups according to the responsiveness to LH-RH-a: group A patients reached menopause after LH-RH-a, whereas resumption of menstruation occurred within 12 weeks after cessation of therapy in group B. INTERVENTIONS: Luteinizing hormone-releasing hormone agonist was administered intranasally three times a day with 150 micrograms insufflation of one spray in each nostril (total dose: 900 micrograms/d). MAIN OUTCOME MEASURES: Efficacies of treatment were assessed in terms of uterine volume, hemoglobin concentrations, serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E2), and bone density during and after treatment. RESULTS: In both groups, hemoglobin concentrations increased significantly after 16 weeks of treatment. A significant reduction in uterine volume was observed in both groups. After completing therapy, there was no further significant change in uterine volume in group A, whereas uterine volume in group B returned to pretreatment values. Serum LH and FSH concentrations were suppressed during treatment, but those gonadotropins in group A increased significantly up to the menopausal levels after treatment. Serum E2 concentrations in both groups showed consistent suppression by the end of the first treatment cycle. After cessation of therapy, serum E2 levels on group A remained in the castrate range, whereas E2 in group B returned to pretreatment levels, concomitant with the return of normal ovulation. CONCLUSIONS: Intranasal administration of LH-RH-a was successful in significantly decreasing uterine volume and increasing hemoglobin concentration in premenopausal women with leiomyomata.

Adult↗

PubMed1987

Use of individual human follicles to compare oocyte in vitro fertilization to granulosa cell in vitro luteinization.

Granulosa-lutein (G-L) cells from individual follicles aspirated during cycles of in vitro fertilization-embryo transfer were examined after 3 and 6 days in culture. G-L cells from follicles that contained an oocyte that fertilized in vitro were compared with G-L cells from follicles that contained an oocyte that did not fertilize in vitro. Spent culture media was assayed for progesterone at days 3 and 6 of culture and luteinizing hormone/human chorionic gonadotropin (LH/hCG) receptor content of G-L cells was determined at day 6. G-L cell cultures from follicles that contained an oocyte that fertilized in vitro produced significantly more progesterone over 3 and 6 days of culture than those obtained from follicles in which the oocyte did not fertilize. Furthermore, LH/hCG receptor content after 6 days was significantly higher in G-L cells obtained from follicles with fertilized oocytes compared with follicles with unfertilized oocytes. Increased progesterone output and LH/hCG receptor acquisition demonstrate more maturation or "luteinization" by G-L cells aspirated from individual follicles that contain oocytes that fertilized in vitro.

Cells, Cultured↗