Isotretinoin and FoxO1

PubMed Central

2011-01-01

Oral isotretinoin (13-cis retinoic acid) is the most effective drug in the treatment of acne and restores all major pathogenetic factors of acne vulgaris. isotretinoin is regarded as a prodrug which after isomerizisation to all-trans-retinoic acid (ATRA) induces apoptosis in cells cultured from human sebaceous glands, meibomian glands, neuroblastoma cells, hypothalamic cells, hippocampus cells, Dalton's lymphoma ascites cells, B16F-10 melanoma cells, and neuronal crest cells and others. By means of translational research this paper provides substantial indirect evidence for isotretinoin's mode of action by upregulation of forkhead box class O (FoxO) transcription factors. FoxOs play a pivotal role in the regulation of androgen receptor transactivation, insulin/insulin like growth factor-1 (IGF-1)-signaling, peroxisome proliferator-activated receptor-γ (PPArγ)- and liver X receptor-α (LXrα)-mediated lipogenesis, β-catenin signaling, cell proliferation, apoptosis, reactive oxygene homeostasis, innate and acquired immunity, stem cell homeostasis, as well as anti-cancer effects. An accumulating body of evidence suggests that the therapeutic, adverse, teratogenic and chemopreventive effecs of isotretinoin are all mediated by upregulation of FoxO-mediated gene transcription. These FoxO-driven transcriptional changes of the second response of retinoic acid receptor (RAR)-mediated signaling counterbalance gene expression of acne due to increased growth factor signaling with downregulated nuclear FoxO proteins. The proposed isotretinoin→ATRA→RAR→FoxO interaction offers intriguing new insights into the mode of isotretinoin action and explains most therapeutic, adverse and teratogenic effects of isotretinoin in the treatment of acne by a common mode of FoxO-mediated transcriptional regulation. PMID:22110774

Oral treatment with retinoic acid decreases bone mass in rats.

PubMed

Hotchkiss, Charlotte E; Latendresse, John; Ferguson, Sherry A

2006-12-01

13-cis-retinoic acid (13-cis-RA, isotretinoin) is used to treat severe recalcitrant acne. Other retinoids have adverse effects on bone. Recent studies of human patients treated with 13-cis-RA have had varying results, perhaps because of variability among patients and the lack of control groups. The effects of retinoids have been studied in rodents, but little information is available regarding the effects of clinically relevant retinoid doses as evaluated by use of bone densitometric techniques. We treated rats for 15 or 20 wk with 13-cis-RA, all-trans-RA, or soybean oil (control) by gavage. We used dual-energy X-ray absorptiometry, histomorphometry, and histologic evaluation to evaluate effects on bone. Spontaneous long bone fractures occurred in some rats treated with 15 mg/kg all-trans-RA daily. Bone mineral density, bone mineral content, bone diameter, and cortical thickness of the femur were reduced in rats treated daily with 10 or 15 mg/kg all-trans-RA or 30 mg/kg 13-cis-RA. The lumbar spine was not affected. Although the effects of 13-cis-RA were not as dramatic as those of all-trans-RA, further study of the effects of 13-cis-RA on long bones is warranted.

Isotretinoin in lacrimal gland fluid and tears.

PubMed

Rismondo, V; Ubels, J L

1987-03-01

Isotretinoin (13-cis-retinoic acid) is used in the treatment of severe cystic acne. Adverse ocular reactions, including blepharoconjunctivitis and dry eye symptoms, are frequent side effects of this drug. Our previous observation that retinol is present in tears and lacrimal gland fluid suggests that isotretinoin may also be secreted by the lacrimal gland. Rabbits were treated with isotretinoin, and lacrimal gland fluid was collected from the cannulated lacrimal gland duct. Tears were collected from patients who were being treated with isotretinoin. Lacrimal gland fluid and tears were analyzed by reverse-phase high-pressure liquid chromatography and a peak eluted from each sample, which was identified as isotretinoin. We conclude that the lacrimal gland is able to secrete isotretinoin in addition to retinol and that, in animals and patients treated systemically with isotretinoin, the ocular surface is exposed to the drug via the tear film.

Treatment of gram-negative folliculitis with isotretinoin.

PubMed

Neubert, U; Plewig, G; Ruhfus, A

1986-01-01

The clinical and bacteriological findings are reported in 13 patients with gram-negative folliculitis before, during, and after treatment with isotretinoin (13-cis-retinoic acid). Patients were treated for 14-36 weeks with a daily dose of 0.5-1.5 mg isotretinoin/kg body weight. Inflammatory lesions were counted before and during weeks 2, 4, 8, 12, 16, 20, 24, 28, and 30 of therapy and again up to 172 weeks after cessation of treatment. In all patients there was an impressive improvement in clinical symptoms, especially a decrease in seborrhea and inflammatory lesions. Simultaneously, the gram-negative bacteria disappeared from the facial skin. Full clinical bacteriological remission was achieved in 9 patients within a period of up to 43 months, with minor recurrences of the disease in the remaining 4 patients.

13-cis retinoic acid and isomerisation in paediatric oncology--is changing shape the key to success?

PubMed

Armstrong, Jane L; Redfern, Christopher P F; Veal, Gareth J

2005-05-01

Retinoic acid isomers have been used with some success as chemotherapeutic agents, most recently with 13-cis retinoic acid showing impressive clinical efficacy in the paediatric malignancy neuroblastoma. The aim of this commentary is to review the evidence that 13-cis retinoic acid is a pro-drug, and consider the implications of retinoid metabolism and isomerisation for the further development of retinoic acid for cancer therapy. The low binding affinity of 13-cis retinoic acid for retinoic acid receptors, low activity in gene expression assays and the accumulation of the all-trans isomer in cells treated with 13-cis retinoic acid, coupled with the more-favourable pharmacokinetic profile of 13-cis retinoic acid compared to other isomers, suggest that intracellular isomerisation to all-trans retinoic acid is the key process underlying the biological activity of 13-cis retinoic acid. Intracellular metabolism of all-trans retinoic acid by a positive auto-regulatory loop may result in clinical resistance to retinoic acid. Agents that block or reduce the metabolism of all-trans retinoic acid are therefore attractive targets for drug development. Devising strategies to deliver 13-cis retinoic acid to tumour cells and facilitate the intracellular isomerisation of 13-cis retinoic acid, while limiting metabolism of all-trans retinoic acid, may have a major impact on the efficacy of 13-cis retinoic acid in paediatric oncology.

Role of UDP-glucuronosyltransferase isoforms in 13-cis retinoic acid metabolism in humans.

PubMed

Rowbotham, Sophie E; Illingworth, Nicola A; Daly, Ann K; Veal, Gareth J; Boddy, Alan V

2010-07-01

13-cis Retinoic acid (13cisRA, isotretinoin) is an important drug in both dermatology, and the treatment of high-risk neuroblastoma. 13cisRA is known to undergo cytochrome P450-mediated oxidation, mainly by CYP2C8, but phase II metabolic pathways have not been characterized. In the present study, the glucuronidation activities of human liver (HLM) and intestinal microsomes (HIM), as well as a panel of human UDP-glucuronosyltransferases (UGTs) toward both 13cisRA and the 4-oxo metabolite, 4-oxo 13cisRA, were compared using high-performance liquid chromatography. Both HLM and, to a greater extent, HIM catalyzed the glucuronidation of 13cisRA and 4-oxo 13cisRA. Based on the structures of 13cisRA and 4-oxo 13cisRA, the glucuronides formed are conjugated at the terminal carboxylic acid. Further analysis revealed that UGT1A1, UGT1A3, UGT1A7, UGT1A8, and UGT1A9 were the major isoforms responsible for the glucuronidation of both substrates. For 13cisRA, a pronounced substrate inhibition was observed with individual UGTs and with HIM. UGT1A3 exhibited the highest rate of activity toward both substrates, and a high rate of activity toward 13cisRA glucuronidation was also observed with UGT1A7. However, for both substrates, K(m) values were above concentrations reported in clinical studies. Therefore, UGT1A9 is likely to be the most important enzyme in the glucuronidation of both substrates as this enzyme had the lowest K(m) and is expressed in both the intestine and at high levels in the liver.

13-cis-retinoic acid metabolism in vivo. The major tissue metabolites in the rat have the all-trans configuration.

PubMed

McCormick, A M; Kroll, K D; Napoli, J L

1983-08-02

The liver and intestinal metabolites of orally dosed 13-cis-[11-3H]retinoic acid were analyzed in normal and 13-cis-retinoic acid treated rats 3 h after administration of the radiolabeled retinoid. all-trans-Retinoic acid was identified as a liver and intestinal mucosa metabolite in normal rats given physiological doses of 13-cis-[3H]retinoic acid. all-trans-Retinoyl glucuronide was identified as the most abundant radiolabeled metabolite in mucosa and a prominent liver metabolite under the same conditions. Thus, the major 13-cis-retinoic acid metabolites retained in liver and mucosa, two retinoid target tissues, had the all-trans configuration. These data indicate that the isomerization of 13-cis-retinoic acid to all-trans-retinoic acid and the subsequent conversion to all-trans-retinoyl glucuronide are central events in the in vivo metabolism of 13-cis-retinoic acid in the rat. Moreover, the all-trans-retinoic acid detected in vivo could account for a significant fraction of the physiological activity of 13-cis-retinoic acid. The tissue disposition and metabolism of orally dosed 13-cis-[3H]retinoic acid are modulated by retinoid treatment. Chronic 13-cis-retinoic acid treatment apparently increased the intestinal accumulation of all-trans-retinoic acid, all-trans-retinoyl glucuronide, and 13-cis-retinoyl glucuronide. The liver concentrations of tritiated all-trans-retinoic acid and all-trans-retinoyl glucuronide were also elevated in 13-cis-retinoic acid treated rats.

UV-induced isomerization of oral retinoids in vitro and in vivo in hairless mice.

PubMed

Berne, B; Rollman, O; Vahlquist, A

1990-08-01

Ultraviolet (UV) irradiation causes isomerization and destruction of many vitamin A analogues (retinoids). Using high-performance liquid chromatography (HPLC), we investigated in vitro and in vivo the effects of UV irradiation on 2 all-trans aromatic retinoids (etretinate and acitretin) and on 13-cis retinoic acid (isotretinoin). When etretinate and acitretin dissolved in ethanol were irradiated with UVB (280-320 nm; 10-336 mJ/cm2) or UVA (320-400 nm; 1-5 J/cm2), extensive and reproducible cis-isomerizations occurred at the 13-position (cis/trans ratio approximately 1.6 in all experiments) but there was no progressive photodegradation of the molecules. Irradiation of isotretinoin produced only moderate trans-isomerization but the sum of HPLC peak heights fell with increasing UV doses, being 72% of the original value after 336 mJ/cm2 of UVB. Hairless mice were given etretinate (50 mg/kg bw), acitretin (200 mg/kg) or isotretinoin (50 mg/kg) on days 1, 4 and 7 and were irradiated daily for 8 d with 13 mJ/cm2 UVB plus 1 J/cm2 UVA. Samples of serum, dorsal skin and liver were collected and retinoids analyzed by HPLC. In the etretinate and acitretin-treated, irradiated animals the serum concentrations of the 13-cis isomers were 2-6 times higher than in nonirradiated controls. Irradiated epidermis also contained significantly higher concentrations of 13-cis etretinate and 13-cis acitretin than did control epidermis. The serum and epidermal concentrations of all-trans etretinate and acitretin were unchanged or even increased after irradiation.(ABSTRACT TRUNCATED AT 250 WORDS)

Identification of 4-oxo-13-cis-retinoic acid as the major metabolite of 13-cis-retinoic acid in human blood.

PubMed

Vane, F M; Buggé, C J

1981-01-01

The metabolites of 13-cis-retinoic acid (Accutane) were investigated in blood samples from human volunteers on chronic treatment for dermatological disorders. The major metabolite was isolated by reverse-phase high-pressure liquid chromatography and identified as 4-oxo-13-cis-retinoic acid by comparison of its mass and NMR spectra to the spectra of the reference compound. 4-Oxo-all-trans-retinoic acid was also identified, but the extent to which this compound was a metabolite of 13-cis-retinoic acid or an artifactual isomerization product of the major metabolite is unknown. Chromatographic data suggested that small amounts of 13-cis-retinoic acid, 4-hydroxy-13-cis-retinoic acid, and dioxygenated metabolites of 13-cis-retinoic acid may also be present in the blood. This study indicates that a major metabolic pathway of 13-cis-retinoic acid in humans is oxidation at C4 of the cyclohexenyl group.

Isotretinoin conundrum: a randomized, openlabel, crossover study in Mexico to evaluate the bioavailability and bioequivalence of three pharmaceutical preparations of isotretinoin in healthy participants.

PubMed

Piñeyro-Garza, Everardo; Gómez-Silva, Magdalena; Gamino Peña, María Elena; Palmer, Jonathan; Berber, Arturo

2015-10-01

The oral retinoid agent isotretinoin (13-cis-retinoic acid) is approved for the treatment of severe recalcitrant cystic acne. For registrational renewal of Oratane® in Mexico (isotretinoin; Laboratorios Dermatologicos Darier S.A. de C.V., Mexico), it was necessary to establish bioequivalence to the reference product Roaccutan® (Isotretinoin; Roche, Mannheim, Germany). Three prior studies failed to establish the bioequivalence of Oratane to Mexican-sourced Roaccutan. However, 13 studies demonstrated the bioequivalence of Oratane to Roaccutane® from multiple sources. This study compared the bioavailability of Oratane with that of Mexicansourced Roaccutan and Australian-sourced Roaccutane. Study participants received each of the three agents in a randomized, open-label, 6-sequence, 3-way crossover study with a 2-week washout period between treatments. Pharmacokinetic analysis revealed that peak plasma concentration (Cmax) and area under the plasma concentration-time curve from time 0 (dosing) to infinite time (AUC0-∞) were lower for Roaccutan than for Roaccutane and Oratane (Cmax: 1,023.35, 1,223.08, and 1,224.25 ng/mL, respectively; AUC0-∞: 13,653.65, 15,681.35 and 15,733.55 ng/mL x h, respectively). The 90% CIs (test/reference) for the ratios of the geometric means indicated that Oratane was bioequivalent to Roaccutane but not to Roaccutan. In addition, Roaccutane (R2) was not bioequivalent to Roaccutan (R1; R1/R2 90% CIs: Cmax, 76.12 - 91.04; AUC0-t, 82.19 - 91.13; AUC0-∞, 82.94 - 91.57). Oratane and Australian-sourced Roaccutane could be considered bioequivalent, but neither formulation was found to be bioequivalent to Mexican-sourced Roaccutan.

Steady state pharmacokinetics of oral treatment with 13-cis-retinoic acid or all-trans-retinoic acid in male and female adult rats.

PubMed

Ferguson, Sherry A; Siitonen, Paul H; Cisneros, F Javier; Gough, Bobby; Young, John F

2006-06-01

Male and female Sprague-Dawley rats were orally gavaged with 13-cis-retinoic acid (7.5 or 15 mg/kg) or all-trans-retinoic acid (10 or 15 mg/kg) for 7 consecutive days. Blood was collected out to 8 hr after the last gavage on day 7. HPLC serum concentrations of 13-cis-retinoic acid, all-trans-retinoic acid, and 13-cis-4-oxo-retinoic acid were subjected to model independent pharmacokinetic analyses. Peak serum levels of 563 to 1640 ng/ml were observed for rats treated with 13-cis-retinoic acid at 1.5-2 hr after gavage. Peak serum levels of 183 to 267 ng/ml at 1.5 hr after gavage were observed for all-trans-retinoic acids. The elimination half-life of 13-cis-retinoic acid was about 1.5 hr while the elimination half-life of all-trans-retinoic acid was slightly longer. There were no sex differences for any parameter. Serum levels resulting from the 7.5 mg/kg 13-cis-retinoic acid were similar to those of human Accutane users.

Comparative teratology and transplacental pharmacokinetics of all-trans-retinoic acid, 13-cis-retinoic acid, and retinyl palmitate following daily administrations in rats.

PubMed

Collins, M D; Tzimas, G; Hummler, H; Bürgin, H; Nau, H

1994-07-01

The retinoids are teratogenic in a wide variety of species. In the rat, 13-cis-retinoic acid and retinyl palmitate are significantly less potent teratogens than all-trans-retinoic acid. This investigation questioned whether differing teratogenic potencies of these moieties can be correlated with the concentrations of these drugs and/or metabolites in the embryonic compartment. Approximately equipotent teratogenic doses of these three retinoids were administered and the pharmacokinetics in maternal plasma and embryo of the most prevalent vitamin A metabolites were measured. The glucuronides of the respective retinoids were the predominant metabolites in the maternal plasma, but were not detected in the embryo. Also, the transport of 13-cis-retinoic acid across the placenta occurred to a much lesser extent than the transport of all-trans-retinoic acid. Administration of either all-trans- or 13-cis-retinoic acid causes a depression in the endogenous retinol concentration. This depression is more pronounced in the maternal plasma than in the embryo. The depression of the retinol level in both plasma and embryo after 13-cis-retinoic acid administration (75 mg/kg/day) was greater than the depression after all-trans-retinoic acid (6 mg/kg/day), corroborating the inferential teratological data that the 13-cis-retinoic acid dose was more embryotoxic than the all-trans-retinoic acid dose. Although the dose of all-trans-retinoic acid was less embryotoxic than that of either 13-cis-retinoic acid or retinyl palmitate, the embryonic exposure to all-trans-retinoic acid was considerably larger, as determined by maximum concentration or area under the concentration-versus-time curve, after administration of all-trans-retinoic acid than after either retinyl palmitate or 13-cis-retinoic acid application. These results suggest that embryonic retinoids other than all-trans-retinoic acid--including the administered substances themselves--are important in the teratogenic process induced by 13-cis-retinoic acid and retinyl palmitate.

Identification and quantitation of all-trans- and 13-cis-retinoic acid and 13-cis-4-oxoretinoic acid in human plasma.

PubMed

Eckhoff, C; Nau, H

1990-08-01

Human plasma was analyzed by high performance liquid chromatography for the presence of retinoic acid and 4-oxoretinoic acid isomers. Peaks that coeluted with the reference compounds all-trans-retinoic acid, 13-cis-retinoic acid, and 13-cis-4-oxoretinoic acid were routinely observed in human plasma. These retinoids were unequivocally identified by the following methods: comigration with reference compounds under several high performance liquid chromatographic conditions; comparison of ultraviolet spectra with those of reference compounds; derivatization with diazomethane and coelution of the methyl esters with reference compounds in a high performance liquid chromatographic system as well as in a gas chromatography system with a mass selective detector. In vitro formation of 13-cis-retinoic acid and 13-cis-4-oxoretinoic acid as artifacts during the analytical procedure was excluded by control experiments. The mean plasma concentrations of the vitamin A metabolites in ten male volunteers were: all-trans-retinoic acid: 1.32 +/- 0.46 ng/ml; 13-cis-retinoic acid: 1.63 +/- 0.85 ng/ml; and 13-cis-4-oxoretinoic acid: 3.68 +/- 0.99 ng/ml. After oral dosing with vitamin A (833 IU/kg body weight) in five male volunteers, mean plasma all-trans-retinoic acid increased to 3.92 +/- 1.40 ng/ml and 13-cis-retinoic acid increased to 9.75 +/- 2.18 ng/ml. Maximal plasma 13-cis-4-oxoretinoic acid concentrations (average 7.60 +/- 1.45 ng/ml) were observed 6 h after dosing which was the last time point in this study. Concentrations of all-trans-4-oxoretinoic acid were low or not detectable. Our findings suggest that, in addition to all-trans-retinoic acid, 13-cis-retinoic acid and 13-cis-4-oxoretinoic acid are present in normal human plasma as metabolites of vitamin A.

Cooxidation of 13-cis-retinoic acid by prostaglandin H synthase.

PubMed

Samokyszyn, V M; Sloane, B F; Honn, K V; Marnett, L J

1984-10-30

Cooxidative metabolism of 13-cis-retinoic acid (13-CIS) via prostaglandin H synthase was investigated employing ram seminal vesicle microsomes. Oxidation of 13-CIS utilizing H2O2, 13-hydroperoxy-9-cis-11-trans-octadecadienoic acid (13-OOH-18:2), or 1-hydroperoxy-5-phenyl-4-pentene was detected by measurement of O2 incorporation. UV spectroscopy and HPLC of extracted incubation mixtures demonstrated that 13-CIS was metabolized to oxidized derivatives. Similar spectral changes and HPLC profiles were obtained with H2O2, 13-OOH-18:2, or arachidonic acid as substrates. 4-Hydroxy-13-cis-retinoic acid and all trans-retinoic acid were products of cooxidation as well as other polar metabolites. Oxidation was inhibited by the antioxidant butylated hydroxyanisole and the spin trap, nitrosobenzene. These results indicate that 13-cis-retinoic acid is cooxidized by prostaglandin H synthase and suggest a free radical mechanism resembling that of lipid peroxidation.

In vitro and in vivo metabolism of all-trans- and 13-cis-retinoic acid in hamsters. Identification of 13-cis-4-oxoretinoic acid.

PubMed

Frolik, C A; Roller, P P; Roberts, A B; Sporn, M B

1980-09-10

Administration of either all-trans-[3H]- or 13-cis-[3H]retinoic acid to hamsters fed a normal diet results in the formation of a number of polar metabolites. At least one of these metabolites has been shown to be common to both isomers of retinoic acid and can be generated in a hamster liver 10,000 X g supernatant system using 13-cis-retinoic acid as substrate. It has been identified as 13-cis-4-oxoretinoic acid by mass spectral, ultraviolet absorption, and proton NMR characteristics, as well as by its co-migration with synthetic 13-cis-4-oxoretinoic acid in two different high pressure liquid chromatographic systems. In addition, its metabolic precursor, 13-cis-4-hydroxyretinoic acid, has been tentatively identified. These compounds are believed to be early metabolites in the elimination pathway of retinoic acid from the body.

Determination of endogenous levels of 13-cis-retinoic acid (isotretinoin), all-trans-retinoic acid (tretinoin) and their 4-oxo metabolites in human and animal plasma by high-performance liquid chromatography with automated column switching and ultraviolet detection.

PubMed

Wyss, R; Bucheli, F

1997-10-24

A highly sensitive HPLC method with automated column switching was developed for the simultaneous determination of endogenous levels of 13-cis-retinoic acid (isotretinoin), all-trans-retinoic acid (tretinoin) and their 4-oxo metabolites in plasma samples from man, Cynomolgus monkey, rabbit, rat and mouse. Plasma (0.4 ml) was deproteinated by adding ethanol (1.5 ml) containing the internal standard acitretin. After centrifugation, 1.4 ml of the supernatant were directly injected onto the precolumn packed with LiChrospher 100 RP-18 (5 microm). 1.25% ammonium acetate and acetic acid-ethanol (8:2, v/v) was used as mobile phase during injection and 1% ammonium acetate and 2% acetic acid-ethanol (102:4, v/v) was added, on-line, to decrease the elution strength of the injection solution. After backflush purging of the precolumn, the retained components were transferred to the analytical column in the backflush mode, separated by gradient elution and detected at 360 nm. Two coupled Superspher 100 RP-18 endcapped columns (both 250x4 mm) were used for the separation, together with a mobile phase consisting of acetonitrile-water-10% ammonium acetate-acetic acid: (A) 600:300:60:10 (v/v/v/v), (B) 950:20:5:20 (v/v/v/v), and (C) 990:5:0:5 (v/v/v/v). The method was linear in the range 0.3-100 ng/ml, at least, with a quantification limit of 0.3 ng/ml. The mean recoveries from human plasma were 93.2%-94.4% and the mean inter-assay precision was 2.8%-3.2% (range 0.3-100 ng/ml). Similar results were obtained for animal plasma. The analytes were found to be stable in the plasma of all investigated species stored at -20 degrees C for 4.3 months and at -80 degrees C for 9 months, at least. At this temperature, human plasma samples were even stable for 2 years. The method was successfully applied to more than 6000 human and 1000 animal plasma samples from clinical and toxicokinetic studies. Endogenous levels determined in control patients and pregnant women were similar to published data from volunteers.

ASDS Guidelines Task Force: Consensus Recommendations Regarding the Safety of Lasers, Dermabrasion, Chemical Peels, Energy Devices, and Skin Surgery During and After Isotretinoin Use.

PubMed

Waldman, Abigail; Bolotin, Diana; Arndt, Kenneth A; Dover, Jeffrey S; Geronemus, Roy G; Chapas, Anne; Iyengar, Sanjana; Kilmer, Suzanne L; Krakowski, Andrew C; Lawrence, Naomi; Prather, Heidi B; Rohrer, Thomas E; Schlosser, Bethanee J; Kim, John Y S; Shumaker, Peter R; Spring, Leah K; Alam, Murad

2017-10-01

Currently, the isotretinoin (13-cis-retinoic acid) package insert contains language advising the discontinuation of isotretinoin for 6 months before performing cosmetic procedures, including waxing, dermabrasion, chemical peels, laser procedures, or incisional and excisional cold-steel surgery. It is common practice to follow this standard because of concerns regarding reports of sporadic adverse events and increased risk of scarring. To develop expert consensus regarding the safety of skin procedures, including resurfacing, energy device treatments, and incisional and excisional procedures, in the setting of concurrent or recent isotretinoin use. The American Society for Dermatologic Surgery authorized a task force of content experts to review the evidence and provide guidance. First, data were extracted from the literature. This was followed by a clinical question review, a consensus Delphi process, and validation of the results by peer review. The task force concluded that there is insufficient evidence to justify delaying treatment with superficial chemical peels and nonablative lasers, including hair removal lasers and lights, vascular lasers, and nonablative fractional devices for patients currently or recently exposed to isotretinoin. Superficial and focal dermabrasion may also be safe when performed by a well-trained clinician.

The Role of Isotretinoin Therapy for Cushing's Disease: Results of a Prospective Study

PubMed Central

Vilar, Lucio; Albuquerque, José Luciano; Lyra, Ruy; Trovão Diniz, Erik; Rangel Filho, Frederico; Gadelha, Patrícia; Thé, Ana Carolina; Ibiapina, George Robson; Gomes, Barbara Sales; Santos, Vera; Melo da Fonseca, Maíra; Frasão Viana, Karoline; Lopes, Isis Gabriella; Araújo, Douglas; Naves, Luciana

2016-01-01

Objective. This prospective open trial aimed to evaluate the efficacy and safety of isotretinoin (13-cis-retinoic acid) in patients with Cushing's disease (CD). Methods. Sixteen patients with CD and persistent or recurrent hypercortisolism after transsphenoidal surgery were given isotretinoin orally for 6–12 months. The drug was started on 20 mg daily and the dosage was increased up to 80 mg daily if needed and tolerated. Clinical, biochemical, and hormonal parameters were evaluated at baseline and monthly for 6–12 months. Results. Of the 16 subjects, 4% (25%) persisted with normal urinary free cortisol (UFC) levels at the end of the study. UFC reductions of up to 52.1% were found in the rest. Only patients with UFC levels below 2.5-fold of the upper limit of normal achieved sustained UFC normalization. Improvements of clinical and biochemical parameters were also noted mostly in responsive patients. Typical isotretinoin side-effects were experienced by 7 patients (43.7%), though they were mild and mostly transient. We also observed that the combination of isotretinoin with cabergoline, in relatively low doses, may occasionally be more effective than either drug alone. Conclusions. Isotretinoin may be an effective and safe therapy for some CD patients, particularly those with mild hypercortisolism. PMID:27034666

Hydroperoxide-dependent cooxidation of 13-cis-retinoic acid by prostaglandin H synthase.

PubMed

Samokyszyn, V M; Marnett, L J

1987-10-15

Reverse phase high pressure liquid chromatography was employed to separate the major products resulting from the hydroperoxide-dependent cooxidation of 13-cis-retinoic acid by microsomal and purified prostaglandin H (PGH) synthase. Several major oxygenated metabolites including 4-hydroxy-, 5,6-epoxy-, and 5,8-oxy-13-cis-retinoic acid were unambiguously identified on the basis of cochromatography with authentic standards, uv spectra, and mass spectral analysis. Identical product profiles were generated regardless of the type of oxidizing substrate employed, and heat-denatured microsomes or enzyme did not support oxidation. In addition, several geometric isomers including all trans-retinoic acid were identified. Isomerization to all trans-retinoic acid in microsomes occurred in the absence of exogenous hydroperoxide, was insensitive to inhibition by antioxidant, and was eliminated when heat-denatured preparations were substituted for intact microsomes. Conversely, isomerization to at least one other isomer required the addition of hydroperoxide and was sensitive to antioxidant inhibition. Addition of antioxidant to microsomal incubation mixtures inhibited the hydroperoxide-dependent generation of 5,6-epoxy- and 5,8-oxy-13-cis-retinoic acid and other oxygenated metabolites but stimulated the formation of 4-hydroxy-13-cis-retinoic acid. Under standard conditions, 77% of the original retinoid was metabolized resulting in products containing 1.25 oxygen atoms/oxygenated metabolite, and two dioxygen molecules were consumed per hydroperoxide reduced. Purified PGH synthase also supported O2 uptake during cooxidation of 13-cis-retinoic acid by H2O2 or 5-phenyl-4-pentenyl-1-hydroperoxide, and the initial velocities of O2 uptake were directly proportional to enzyme concentration. 13-cis-Retinoic acid effectively inhibited peroxidase-dependent cooxidation of guaiacol indicating a direct interaction of retinoid with peroxidase iron-oxo intermediates, and EPR spin trapping studies demonstrated the formation of retinoid-derived free radical intermediates. Incubating H2O2 with microsomal PGH synthase resulted in the initiation of lipid peroxidation, detected via measurement of malondialdehyde generation, that was inhibited by retinoid and suggests some limited involvement of lipid peroxidation in retinoid oxidation. Incubation of 13-cis-retinoic acid with hematin and 15-hydroperoxy-5,8,11,13-eicosatetraenoic acid in the presence of detergent, a system that generates high yields of peroxyl radicals, resulted in high yields of 5,6-epoxide; 4-hydroxy-13-cis-retinoic acid was not detected.(ABSTRACT TRUNCATED AT 400 WORDS)

Conceptual biotransformation of 4-oxo-all-trans-retinoic acid, 4-oxo-13-cis-retinoic acid and all-trans-retinoyl-beta-glucuronide in rat whole embryo culture.

PubMed

Creech Kraft, J; Juchau, M R

1992-05-28

In cultured rat conceptuses, intraamniotic microinjections of 2500 ng/mL of 4-oxo-13-cis-retinoic acid, 600 ng/mL 4-oxo-all-trans-retinoic acid or 4000 ng/mL all-trans-retinoyl-beta-glucuronide, produce qualitatively and quantitatively similar patterns of dysmorphogenesis as those reported after the intraamniotic microinjection of 250 ng/mL all-trans-retinoic acid [Lee et al., Teratology 44: 313-323, 1991; Creech Kraft et al., Teratology 45: 259-270, 1992]. In the present study, we utilized HPLC techniques to analyze retinoid levels in cultured rat conceptuses, 1.5 hr after intraamniotic microinjections of 4-oxo-13-cis-retinoic acid (2500 ng/mL), 4-oxo-all-trans-retinoic acid (600 ng/mL) or all-trans-retinoyl-beta-glucuronide (4000 ng/mL). Our findings show that, after the microinjections of 4-oxo-all-trans-retinoic acid or 4-oxo-13-cis-retinoic acid (at these selected concentrations), 4-oxo-all-trans-retinoic acid was predominant in the embryos proper at concentrations of about 200 nM. This was roughly equivalent to the levels of all-trans-retinoic acid assayed after microinjections of all-trans-retinoyl-beta-glucuronide (4000 ng/mL). We conclude from these studies that both 4-oxo-all-trans-retinoic acid and all-trans-retinoic acid behave as ultimate or proximate dysmorphogens.

Determination of 13-cis-retinoic acid and its major metabolite, 4-oxo-13-cis-retinoic acid, in human blood by reversed-phase high-performance liquid chromatography.

PubMed

Vane, F M; Stoltenborg, J K; Buggé, C J

1982-02-12

A high-performance liquid chromatography (HPLC) method for the quantitation of 13-cis-retinoic acid (13-cis-RA) and its major metabolite, 4-oxo-13-cis-RA, in human blood has been developed. The method includes extraction of 1 ml of blood with diethyl ether at pH 6 and the analysis of the extract by reversed-phase HPLC with solvent programming and detection at 365 nm. The quantitation ranges for 13-cis-RA and 4-oxo-13-cis-RA are 10--2000 and 50--2000 ng/ml of blood, respectively. The method also provides estimates of the concentrations of all-trans-RA and 4-oxo-all-trans-RA. The mean intra- and inter-assay variabilities for all four compounds were 6% or less. The method separates 13-cis-RA and 4-oxo-13-cis-RA from 9-cis-RA, all-trans-RA, 4-oxo-all-trans-RA, and some other possible metabolites, such as hydroxy and epoxy retinoic acids. The method has been successfully applied to the analyses of over 1200 blood samples from four 13-cis-RA clinical studies.

Increased concentrations of endogenous 13-cis- and all-trans-retinoic acids in diffuse idiopathic skeletal hyperostosis, as demonstrated by HPLC.

PubMed

Periquet, B; Lambert, W; Garcia, J; Lecomte, G; De Leenheer, A P; Mazieres, B; Thouvenot, J P; Arlet, J

1991-11-09

Endogenous 13-cis- and all-trans-retinoic acids have been quantitated in human serum using a solvent extraction procedure followed by isocratic reversed phase high performance liquid chromatography and UV detection. In healthy adults, after an overnight fasting period, the concentrations of 13-cis- and all-trans-retinoic acids yielded 5.3 +/- 2.43 nmol/l and 11.8 +/- 3.3 nmol/l, respectively (mean +/- SD). The method has been successfully applied to the analysis of both isomers in serum from patients with idiopathic skeletal hyperostosis in whom, the 13-cis- as well as all-trans-retinoic acid levels were raised as compared to the control group.

Vitamin D3 and its synthetic analogue secocholestra-trien-1,2, 24-triol influence the metabolism and the isomerization of retinoic acid in human keratinocytes.

PubMed

Jugert, F K; Roos, T C; Notzon, I; Merk, H F

1998-01-01

Vitamin D and vitamin A acid share metabolic pathways thereby influencing their benefit as a given drug. Little is known concerning their metabolic interactions in epidermal cells. We compared the influence of 1,25-dihydroxycholecalciferol (vitamin D3 - VD3) and its synthetic analogue secocholestra-trien-1,3,24-triol (tacalcitol - TAC) in combination with different calcium concentrations (Ca) on the metabolism and the isomerization of retinoic acid (RA) in cultured primary human keratinocytes. After preincubation with 0.09, 0.6 and 1.2 mM Ca for 24 h, followed by the addition of 10(-6), 10(-8) or 10(-10) M VD3 or TAC, we added 10(-5) M 13-cis-RA (isotretinoin). 24 h later, concentrations of RA isomers and oxidated RA metabolites were measured by RP-HPLC. VD3 (10(-6) M) inhibited the isomerization of 13-cis-RA to all-trans-RA (tretinoin) and 9-cis-RA independently from the Ca concentration in the culture medium. 10(-6)-10(-10) M TAC equally inhibit the 4-hydroxylation of all-trans-RA significantly (12.8 vs. 6.7% of total RA), thereby reducing the amount of irreversible inactivated 4-oxo-all-trans-RA, leading to a higher persistence of all-trans-RA, the active hormone. Both VD3 and its analogue TAC influence the metabolism of RA, a well-known regulator of epithelial cell proliferation and differentiation processes, in two distinct ways. Further studies are necessary to test the hypothesis that the hormone activity of RA can be increased by concomitant treatment with VD3 which prolongs the persistence of 13-cis-RA, and TAC elevating the intracellular concentration of all-trans-RA.

Simultaneous quantification of various retinoids by high performance liquid chromatography: its relevance to alcohol research.

PubMed

Yokoyama, H; Matsumoto, M; Shiraishi, H; Ishii, H

2000-04-01

We established a high performance liquid chromatography system that allowed simultaneous quantification of various retinoids. We applied the retinoids to a high performance liquid chromatography system with a silica gel absorption column. Samples were separated by the system with a binary multistep gradient with two kinds of solvent that contained n-Hexan, 2-propanol, and glacial acetic acid in different ratios. Each retinoid was detected at a wavelength of 350 nm. This condition allowed separation of 13-cis-retinoic acid, 9-cis-retinoic acid, all-trans-retinoic acid, 13-cis-retinol, all-trans-retinol, all-trans-4-oxo-retinoic acid, and 13-cis-4-oxo-retinoic acid as distinct single peaks. Each retinoid was also analyzed separately and its retention time determined. To ascertain the reliability of this system for retinoid quantification, retinoids at various concentrations were applied to the system. We observed the linearities between the concentration and area under the curve of the peak for each retinoid by linear least-squares regression analysis up to 2.5 ng/ml for all retinoic acids and up to 5 ng/ml for all retinols. There was no significant scattering in tests of within-day reproducibility or day-to-day reproducibility. Using this system, we examined effects of light exposure on isomerization of retinoids. When retinoids were exposed to room light for 2 hr, the amounts of all but 13-cis-retinol changed significantly. In particular, the amounts of all-trans-retinoic acid and 9-cis-retinoic acid were reduced by 40% and 60%, respectively. The HPLC system established in this study should be useful for studying the oxidation pathway of retinol to retinoic acid. A light-shielded condition is required when particular retinoic acids are analyzed.

Oral isotretinoin (13-cis-retinoic acid) therapy in severe acne: drug and vitamin A concentrations in serum and skin.

PubMed

Rollman, O; Vahlquist, A

1986-04-01

The disposition of oral isotretinoin to the skin and the effects of the drug on the vitamin A levels in serum and skin were studied in 17 patients with nodulocystic acne. All patients received 0.5 mg/kg/day for 3 months and 8 patients continued treatment with 0.75 mg/kg/day for another 3 months. The parent drug, the major metabolite (4-oxo-isotretinoin), and 2 natural retinoids (retinol and dehydroretinol) were monitored in serum and biopsies of uninvolved skin, using adsorption high-pressure liquid chromatography. During the initial 3 months of treatment the mean isotretinoin level in the serum was 145 ng/ml and in the epidermis 73 ng/g. The corresponding values for 4-oxo-isotretinoin were 615 and 113 ng/g, respectively. Even at the highest dosage there was no progressive accumulation of isotretinoin in serum, epidermis, or subcutis. After discontinuation of therapy the drug disappeared from both serum and skin within 2-4 weeks. The serum transport of vitamin A, monitored by the concentrations of retinol, retinol-binding protein, and prealbumin (transthyretin), was not affected by the treatment. By contrast, the retinol level in the epidermis increased by an average of 53% (p less than 0.01) and the dehydroretinol level decreased by 79% (p less than 0.001) as a result of 3 months of treatment. Both changes were reversible. The results suggest that isotretinoin therapy interferes with the endogenous vitamin A metabolism in the skin.

Rapid determination of retinoic acid and its main isomers in plasma by second-order high-performance liquid chromatography data modeling.

PubMed

Teglia, Carla M; Cámara, María S; Goicoechea, Héctor C

2014-12-01

This paper reports the development of a method based on high-performance liquid chromatography (HPLC) coupled to second-order data modeling with multivariate curve resolution-alternating least-squares (MCR-ALS) for quantification of retinoic acid and its main isomers in plasma in only 5.5 min. The compounds retinoic acid (RA), 13-cis-retinoic acid, 9-cis-retinoic acid, and 9,13-di-cis-retinoic acid were partially separated by use of a Poroshell 120 EC-C18 (3.0 mm × 30 mm, 2.7 μm particle size) column. Overlapping not only among the target analytes but also with the plasma interferents was resolved by exploiting the second-order advantage of the multi-way calibration. A validation study led to the following results: trueness with recoveries of 98.5-105.9 % for RA, 95.7-110.1 % for 13-cis-RA, 97.1-110.8 % for 9-cis-RA, and 99.5-110.9 % for 9,13-di-cis-RA; repeatability with RSD of 3.5-3.1 % for RA, 3.5-1.5 % for 13-cis-RA, 4.6-2.7 % for 9-cis-RA, and 5.2-2.7 % for 9,13-di-cis-RA (low and high levels); and intermediate precision (inter-day precision) with RSD of 3.8-3.0 % for RA, 2.9-2.4 % for 13-cis-RA, 3.6-3.2 % for 9,13-di-cis-RA, and 3.2-2.9 % for 9-cis-RA (low and high levels). In addition, a robustness study revealed the method was suitable for monitoring patients with dermatological diseases treated with pharmaceutical products containing RA and 13-cis-RA.

Simultaneous analysis of retinol, all-trans- and 13-cis-retinoic acid and 13-cis-4-oxoretinoic acid in plasma by liquid chromatography using on-column concentration after single-phase fluid extraction.

PubMed

Teerlink, T; Copper, M P; Klaassen, I; Braakhuis, B J

1997-06-20

A reversed-phase high-performance liquid chromatographic method for the simultaneous analysis of retinol, all-trans-retinoic acid, 13-cis-retinoic acid and 13-cis-4-oxoretinoic acid in human plasma and cell culture medium is described. Sample preparation involves precipitation of proteins and extraction of retinoids with 60% acetonitrile. After centrifugation, the acetonitrile content of the supernatant is reduced to 45%, allowing on-column concentration of analytes. Injection volumes up to 2.0 ml (equivalent to 0.525 ml of sample) can be used without compromising chromatographic resolution of all-trans-retinoic acid and 13-cis-retinoic acid. Retinoids were stable in this extract and showed no isomerization when stored in the dark in a cooled autosampler, allowing automated analysis of large series of samples. Recoveries from spiked plasma samples were between 95 and 103%. Although no internal standard was used, the inter-assay precision for all retinoids was better than 6% and 4% at concentrations of 30 nM and 100 nM, respectively. The method is a valuable tool for the study of cellular metabolism of all-trans-retinoic acid, as polar metabolites of this compound can be detected with high sensitivity in cell culture media.

Correlations between conceptal concentrations of all-trans-retinoic acid and dysmorphogenesis after microinjections of all-trans-retinoic acid, 13-cis-retinoic acid, all-trans-retinoyl-beta-glucuronide, or retinol in cultured whole rat embryos.

PubMed

Kraft, J C; Juchau, M R

1992-01-01

Retinol (4,000 ng/ml), all-trans-retinoyl-beta-glucuronide (4,000 ng/ml), and 13-cis-retinoic acid (1,500 ng/ml) each produced dysmorphogenic effects qualitatively similar to those elicited by 250 ng/ml of all-trans-retinoic acid after microinjections of the respective individual retinoids into the amniotic cavities of cultured whole rat embryos. Subsequent HPLC analyses of the cultured whole conceptuses, embryos proper, yolk sacs, and culture media (24 hr after microinjections) indicated that conceptal biotransformation of each of the retinoids had occurred during the culture period. All-trans-retinoic acid was present in the embryos proper at quantitatively similar concentrations (20-100 nM) after microinjections of the selected quantities of each of the microinjected retinoids: retinol, all-trans-retinoyl-beta-glucuronide, 13-cis-retinoic acid, or all-trans-retinoic acid. The results suggested that all-trans-retinoic acid acted as an ultimate dysmorphogen for the retinoids tested with respect to the anomalies monitored in the embryo culture system.

Topical retinoids in acne vulgaris: update on efficacy and safety.

PubMed

Thielitz, Anja; Gollnick, Harald

2008-01-01

Topical retinoids represent a mainstay of acne treatment because they expel mature comedones, reduce microcomedone formation, and exert anti-inflammatory effects. The first-generation retinoid tretinoin (all-trans retinoic acid) and the synthetic third-generation polyaromatics adapalene and tazarotene are approved for acne treatment by the US FDA, whereas topical tretinoin, isotretinoin (13-cis retinoic acid), and adapalene are accredited in Canada and Europe. Topical retinoids have a favorable safety profile distinct from the toxicity of their systemic counterparts. Local adverse effects, including erythema, dryness, itching, and stinging, occur frequently during the early treatment phase. Their impact varies with the vehicle formation, skin type, frequency and mode of application, use of moisturizers, and environmental factors such as sun exposure or temperature. The broad anti-acne activity and safety profile of topical retinoids justifies their use as first-line treatment in most types of non-inflammatory and inflammatory acne. They are also suitable as long-term medications, with no risk of inducing bacterial resistance, for maintenance of remission after cessation of initial combination therapy.

A human induced pluripotent stem cell-based in vitro assay predicts developmental toxicity through a retinoic acid receptor-mediated pathway for a series of related retinoid analogues.

PubMed

Palmer, Jessica A; Smith, Alan M; Egnash, Laura A; Colwell, Michael R; Donley, Elizabeth L R; Kirchner, Fred R; Burrier, Robert E

2017-10-01

The relative developmental toxicity potency of a series of retinoid analogues was evaluated using a human induced pluripotent stem (iPS) cell assay that measures changes in the biomarkers ornithine and cystine. Analogue potency was predicted, based on the assay endpoint of the ornithine/cystine (o/c) ratio, to be all-trans-retinoic acid>TTNPB>13-cis-retinoic acid≈9-cis-retinoic acid>acitretin>etretinate>retinol. These rankings correlate with in vivo data and demonstrate successful application of the assay to rank a series of related toxic and non-toxic compounds. The retinoic acid receptor α (RARα)-selective antagonist Ro 41-5253 inhibited the cystine perturbation caused by all-trans-retinoic acid, TTNPB, 13-cis-retinoic acid, 9-cis-retinoic acid, and acitretin. Ornithine was altered independent of RARα in all retinoids except acitretin. These results suggest a role for an RARα-mediated mechanism in retinoid-induced developmental toxicity through altered cystine metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

The frequency of hematuria in acne vulgaris patients during isotretinoin treatment.

PubMed

Yesilkaya, Burcu; Alli, Nuran; Artuz, R Ferda; Ulu, Ezgi; Kartal, Demet; Cinar, S Levent

2017-03-01

Systemic isotretinoin (13-cis-retinoic acid) is effective in the treatment of acne vulgaris. The most common side effects are mucocutaneous ones. Hematuria seen secondary to isotretinoin treatment is thought to be due to mucosal dryness in the urinary system. This study aims to determine the frequency of hematuria in acne vulgaris patients during isotretinoin treatment. Eighty-eight subjects aged 16-32 years were included in the study group and 52 subjects were in the control group. The subjects were treated for 6 months and were monitored monthly by complete urine analyzes. They were also examined each month in terms of cheilitis, xerosis, epistaxis, rectal bleeding, fatigue, myalgia, weight loss, dry eye, conjunctivitis, headache, dysuria and pollakiuria. In the study group, 15 subjects (17%) had hematuria at least once during the study, and in the control group, four subjects (7.7%) had hematuria. The difference was not statistically significant (p = 0.118). Among the subjects who had hematuria, 11 of them (73.3%) were female and four of them (33.3%) were male in the study group while all the subjects with hematuria in the control group were female. Hematuria and gender did not show a statistically significant correlation. Hematuria was observed in 17% of the study group; this frequency rate was not different from that of the normal population. In subjects having isotretinoin treatment, if all the other reasons or disorders are excluded, one must keep in mind that hematuria may be due to isotretinoin use.

Quantitative high-performance liquid chromatographic determination of retinoids in human serum using on-line solid-phase extraction and column switching. Determination of 9-cis-retinoic acid, 13-cis-retinoic acid, all-trans-retinoic acid, 4-oxo-all-trans-retinoicacid and 4-oxo-13-cis-retinoic acid.

PubMed

Gundersen, T E; Lundanes, E; Blomhoff, R

1997-03-28

A fully automated isocratic high-performance liquid chromatographic method for the determination of 9-cis-retinoic acid, 13-cis-retinoic acid, all-trans-retinoic acid, 4-oxo-13-cis-retinoic acid and 4-oxo-all-trans-retinoic acid, has been developed using on-line solid-phase extraction and a column switching technique allowing clean-up and pre-concentration in a single step. A 500-microliter sample of serum was diluted with 750 microliters of a solution containing 20% acetonitrile and the internal standard 9,10-dimethylanthracene. About 1000 microliters of this mixture was injected on a 20 x 4.6 mm I.D. poly ether ether ketone (PEEK) pre-column with titanium frits packed with Bondapak C18, 37-53 microns, 300 A particles. Proteins and very polar compounds were washed out to waste, from the pre-column, with 0.05% trifluoroacetic acid (TFA)-acetonitrile (8.5:1.5, v/v). More than 200 aliquots of diluted serum could be injected on this pre-column before elevated back-pressure enforces replacement. Components retained on the pre-column were backflushed to the analytical column for separation and detection at 360 nm. Baseline separation was achieved using a single 250 x 4.6 mm I.D. Suplex pKb-100 column and a mobile phase containing 69:10:2:16:3 (v/v) of acetonitrile-methanol-n-butanol-2% ammonium acetate-glacial acetic acid. A total time of analysis of less than 30 min, including sample preparation, was achieved. Recoveries were in the range of 79-86%. The limit of detection was 1-7 ng/ml serum and the precision, in the concentration range 20-1000 ng/ml, was between 1.3 and 4.5% for all five compounds. The method was applied for the analysis of human serum after oral administration of 60 mg Roaccutan. The method is well suited for pharmacological studies, while the endogenous levels of some retinoic acid isomers are below the limit of quantitation.

Single-dose pharmacokinetic study of 13-cis-retinoic acid in man.

PubMed

Besner, J G; Leclaire, R; Band, P; Meloche, S; Deschamps, M; Mailhot, S; Moisan, R; Diorio, G

1985-03-01

A pharmacokinetic study of 13-cis-retinoic acid was performed in nine patients following administration of a single oral dose of 80 mg. An average lag time of 1.2 hours was observed, followed by fast absorption, with a mean half-life of 0.5 hour. Peak plasmatic concentration of 733 ng/ml occurred at 2.3 hours. The disposition profile showed a rapid distribution half-life of 1.3 hours and a terminal elimination half-life of 24.7 hours. No 13-cis-retinoic acid was detected unchanged in urine. An important interpatient variability was noted.

A new approach to highly sensitive determination of retinoic acid isomers by preconcentration with CdSe quantum dots.

PubMed

Torabi, Behzad; Shemirani, Farzaneh

2014-03-01

Unusual amounts of retinoic acid (RA) isomers play an important role in abnormal morphological development of mammals; such as rat embryos. Each isomer of RA has a unique function in first steps of embryonic life. In the current study, a new method for preconcentration and simultaneous determination of all-trans retinoic acid, 13-cis retinoic acid, 9-cis retinoic acid and 9,13-di-cis retinoic acid in rat whole rudimentary embryo culture (RWEC) has been developed. RA isomers were extracted from samples by conjugation to appropriate amount of surface modified CdSe quantum dots (QDs) prior to HPLC/UV determination. In order to quickly release of the analytes with unchanged form, separated RA-QD conjugation were irradiated by intensive near infrared wavelength (NIR). Low energy NIR irradiation results in maintaining the primary forms of RA isomers during the release. The conjugation and release mechanisms were described and experimental parameters were investigated in detail. Under optimized conditions, the method was linear in the range of 0.040-34.600 pmol g(-1) for all-trans RA (R(2)=0.9996), 0.070-34.200 pmol g(-1) for 13-cis RA (R(2)=0.9992), 0.050-35.300 pmol g(-1) for 9,13-di-cis RA (R(2)=0.9998) and 0.050-32.900 pmol g(-1) for 9-cis RA (R(2)=0.9990). The present method can be useful for retinoic acid monitoring in clinical studies. © 2013 Published by Elsevier B.V.

Solid-state stability studies of 13-cis-retinoic acid and all-trans-retinoic acid using microcalorimetry and HPLC analysis.

PubMed

Tan, X; Meltzer, N; Lindebaum, S

1992-09-01

The solid-state stabilities of 13-cis-retinoic acid and all-trans-retinoic acid in the presence and absence of oxygen were investigated. The samples were first evaluated using microcalorimetry. The rate laws of different samples under different conditions were deduced from the shapes of the heat flow curves, and the activation energies of the reactions were determined from Arrhenius plots. Under an air atmosphere, the decomposition of 13-cis-retinoic acid is an autocatalytic reaction, while all-trans-retinoic acid undergoes a zero-order process. The degradation of the two compounds at a selected elevated temperature was also determined utilizing HPLC analysis. This technique confirmed the decomposition kinetics. Hence, their half-lives and shelf lives at room temperature could be calculated. Under a nitrogen atmosphere, the microcalorimetric experiment showed a first-order phenomenon for both samples, but HPLC analysis showed no degradation, suggesting that the two samples, in the absence of oxygen, undergo only a physical change.

[Application of 13-cis-retinoic acid in patients with 131I scintigraphically-negative metastases of differentiated thyroid carcinoma].

PubMed

Adamczewski, Zbigniew; Makarewicz, Jacek; Mikosiński, Sławomir; Knapska-Kucharska, Małgorzata; Gunerska-Szadkowska, Anna; Oszukowska, Lidia; Karwowska, Anzelmina; Lewiński, Andrzej

2006-01-01

The loss of iodine uptake by differentiated thyroid carcinoma (DTC) cells is a major therapeutic problem especially in patients with nonsurgical metastatic foci or local recurrence. Using 13-cis-retinoic acid, it was attempted to retain iodine uptake as a result of redifferentiation (influence by retinoic acid receptors present in DTC cells). Between 1999 and 2005, 13-cis-retinoic acid was used in 11 patients with disseminated PTC and high serum level of thyroglobulin (Tg) before (131)I treatment (2 patients were treated twice - 13 treatment cycles in total). Side effects in skin and mucous membranes were observed in all the patients, however, their intensity did not require termination of the therapy. Increase of iodine uptake was observed in 5 patients (45%). Decreased Tg concentration was observed in 9 patients. In that group, increased (131)I uptake was observed in 4 patients with distant metastases. All determinations of Tg concentrations were carried out under TSH stimulation. 13-cis-retinoic acid causes an increase of radioiodine uptake in around half of treated patients, however, the follow-up of these patients indicates that this increase does not result in either full remission or even stabilisation of neoplastic disease. The possibility should be considered to use cis-retinoic acid as an independent therapeutic approach in patients with radioiodine non-avid foci of thyroid carcinoma especially those showing high expression of RARb and RXRg receptors.

Effect of retinoic acid on aquaporin 3 expression in keratinocytes.

PubMed

Xing, F; Liao, W; Jiang, P; Xu, W; Jin, X

2016-03-11

To explore the possible mechanism of the third-generation retinoic acid drugs (isotretinoin, acitretin, adapalene) in inducing skin and mucosa dryness and rhagades; specifically, mechanism by which these drugs influence keratinocyte cell culture models in vitro (HaCaT) and aquaporin channel (AQP3) protein expression was investigated. Isotretinoin, acitretin, and adapalene were applied to human keratinocyte HaCaT cells. Immunohistochemistry, reverse transcriptase polymerase chain reaction, and western blotting were used to detect their effects on AQP3 expression in HaCaT cells at different concentrations (0.000, 0.001, 0.010, 0.060, and 0.100 mg/mL) or different at times (0, 6, 12, 24, and 48 h). At 0.010 mg/mL, maximal AQP3 expression was observed in HaCaT cells; this was significantly higher than the expressions at the other concentrations (P < 0.05). After treatment with isotretinoin, acitretin, or adapalene at 0.010 mg/mL for 12 h, the expression of AQP3 was the highest in the isotretinoin group, followed by the acitretin group, with the lowest expression in the adapalene group. However, the differences were not statistically significant (P > 0.05). Retinoic acid can increase AQP3 expression in HaCaT cells, with significant effects observed with 0.010 mg/mL isotretinoin treatment for 12 h. The side effects, namely skin and mucosa dryness caused by retinoic acid might be related to its effects on AQP3 expression.

Retinoid agonist isotretinoin ameliorates obstructive renal injury.

PubMed

Schaier, Matthias; Jocks, Thomas; Grone, Hermann-Josef; Ritz, Eberhard; Wagner, Juergen

2003-10-01

Interstitial fibrosis is a major cause of end stage renal failure. Retinoids, which are involved in tissue repair and fibrosis, inhibit inflammatory and proliferative pathways. Therefore, we studied the dose dependent effects of the retinoid receptor agonist isotretinoin 13-cis retinoic acid in the unilateral ureteral obstruction model (UUO). Sham operated control rats were compared with UUO rats treated with vehicle (UUO-Veh), or low (5 mg/kg body weight (UUO-LD) or high (25 mg/kg) (UUO-HD) dose isotretinoin. Kidneys were evaluated using reverse transcriptase-polymerase chain reaction and immunohistology 7 days after UUO. Renal injury and fibrosis were quantified by immunostaining and expression measurements of the genes involved in renal fibrosis. In UUO-Veh kidneys the interstitial area was expanded 5-fold but only 3-fold in UUO-HD and 3.5-fold in UUO-LD rats. Interstitial cell counts were 3-fold higher in UUO-Veh rats but significantly less in UUO-HD or UUO-LD animals. Tubular and interstitial cell proliferation was significantly higher in UUO-Veh rats compared with sham operated control plus vehicle animals but less so in UUO-LD and UUO-HD rats. In UUO-Veh rats interstitial infiltration by monocytes/macrophages was higher compared with unobstructed controls. It was significantly less after isotretinoin treatment. In UUO-Veh rats mRNA for procollagen I, and transforming growth factor-beta1 and II receptor was significantly increased. It was significantly less after treatment with isotretinoin. Fibronectin and collagen I immunostaining was also decreased by isotretinoin. Since isotretinoin limits proliferation, inflammation and fibrosis after UUO, retinoids should be further investigated as potentially promising therapeutic agents for renal disease.

Pharmacology of 13-cis-retinoic acid in humans.

PubMed

Kerr, I G; Lippman, M E; Jenkins, J; Myers, C E

1982-05-01

Vitamin A and its analogs (retinoids) have shown great promise for the chemoprevention of cancer as well as being a possible new class of chemotherapeutic agents. A Phase I and II trial of 13-cis-retinoic acid in advanced cancers was initiated, and the clinical pharmacology of the drug was studied. All patients received p.o. 13-cis-retinoic acid starting at 0.5 mg/kg/day, escalating over 4 weeks to a maximum dose of 8 mg/kg/day in divided doses. Although there was a linear correlation of plasma concentration with dose escalation, large inter-individual variations in peak plasma concentrations were noted. At the maximum drug dose, the mean peak plasma concentration was 4 X 10(-6) M. There was little drug accumulation on this schedule, as trough concentrations between p.o. doses often dropped below 1 X 10(-6) M. The drug was metabolized extensively to a metabolite, the concentrations of which exceeding parent 13-cis-retinoic acid concentrations with chronic dosing. Retinol concentrations were below the normal range.

All-trans-retinoic acid and 13-cis-retinoic acid: pharmacokinetics and biological activity in different cell culture models of human keratinocytes.

PubMed

Schroeder, M; Zouboulis, C C

2007-02-01

Despite its known biological effect on epithelial cells, 13- CIS-retinoic acid shows low binding affinity to either cellular retinoic acid-binding proteins or nuclear retinoid receptors compared to its isomer all- TRANS-retinoic acid. We have postulated a prodrug-drug relation with 13- CIS-retinoic acid which isomerizes to all- TRANS-retinoic acid. On the other hand, the biological effects of these two compounds can differ in the widely used cell culture models of HaCaT and normal primary keratinocytes. In this study, we seeded HaCaT and normal keratinocytes at high densities leading to early confluence in order to imitate high keratinocyte proliferation, such as in acne and psoriasis, while to model decreased keratinocyte proliferation, as in aged and steroid-damaged skin, cells were seeded at a low density. High performance liquid chromatography was administered to examine retinoid uptake and metabolism in monolayer HaCaT and normal keratinocyte cultures and the 4-methylumbelliferyl heptanoate assay to estimate cell growth at different cell densities. Major qualitative and quantitative differences were detected in the two cell types regarding intracellular 13- CIS-retinoic acid isomerization to all- TRANS-retinoic acid. On the other hand, the two retinoic acid isomers showed similar effects on cell growth of both cell types tested with increasing proliferation at low cell densities, but being rather inactive at high ones in normal keratinocytes and exhibiting an antiproliferative effect in HaCaT keratinocytes. The missing effect of retinoids on cell proliferation in high seeding densities of normal keratinocytes may indicate that the normalizing activity of retinoids on hyperkeratotic diseases, such as acne or psoriasis, is likely to be carried out by modulation of cell differentiation than cell growth. On the other hand, induced keratinocyte proliferation in low seeding densities may provide an explanation for the acanthosis induced by topical retinoids in aged and steroid-damaged skin.

Increasing the intracellular availability of all-trans retinoic acid in neuroblastoma cells.

PubMed

Armstrong, J L; Ruiz, M; Boddy, A V; Redfern, C P F; Pearson, A D J; Veal, G J

2005-02-28

Recent data indicate that isomerisation to all-trans retinoic acid (ATRA) is the key mechanism underlying the favourable clinical properties of 13-cis retinoic acid (13cisRA) in the treatment of neuroblastoma. Retinoic acid (RA) metabolism is thought to contribute to resistance, and strategies to modulate this may increase the clinical efficacy of 13cisRA. The aim of this study was to test the hypothesis that retinoids, such as acitretin, which bind preferentially to cellular retinoic acid binding proteins (CRABPs), or specific inhibitors of the RA hydroxylase CYP26, such as R116010, can increase the intracellular availability of ATRA. Incubation of SH-SY5Y cells with acitretin (50 microM) or R116010 (1 or 10 microM) in combination with either 10 microM ATRA or 13cisRA induced a selective increase in intracellular levels of ATRA, while 13cisRA levels were unaffected. CRABP was induced in SH-SY5Y cells in response to RA. In contrast, acitretin had no significant effect on intracellular retinoid concentrations in those neuroblastoma cell lines that showed little or no induction of CRABP after RA treatment. Both ATRA and 13cisRA dramatically induced the expression of CYP26A1 in SH-SY5Y cells, and treatment with R116010, but not acitretin, potentiated the RA-induced expression of a reporter gene and CYP26A1. The response of neuroblastoma cells to R116010 was consistent with inhibition of CYP26, indicating that inhibition of RA metabolism may further optimise retinoid treatment in neuroblastoma.

Increasing the intracellular availability of all-trans retinoic acid in neuroblastoma cells

PubMed Central

Armstrong, J L; Ruiz, M; Boddy, A V; Redfern, C P F; Pearson, A D J; Veal, G J

2005-01-01

Recent data indicate that isomerisation to all-trans retinoic acid (ATRA) is the key mechanism underlying the favourable clinical properties of 13-cis retinoic acid (13cisRA) in the treatment of neuroblastoma. Retinoic acid (RA) metabolism is thought to contribute to resistance, and strategies to modulate this may increase the clinical efficacy of 13cisRA. The aim of this study was to test the hypothesis that retinoids, such as acitretin, which bind preferentially to cellular retinoic acid binding proteins (CRABPs), or specific inhibitors of the RA hydroxylase CYP26, such as R116010, can increase the intracellular availability of ATRA. Incubation of SH-SY5Y cells with acitretin (50 μM) or R116010 (1 or 10 μM) in combination with either 10 μM ATRA or 13cisRA induced a selective increase in intracellular levels of ATRA, while 13cisRA levels were unaffected. CRABP was induced in SH-SY5Y cells in response to RA. In contrast, acitretin had no significant effect on intracellular retinoid concentrations in those neuroblastoma cell lines that showed little or no induction of CRABP after RA treatment. Both ATRA and 13cisRA dramatically induced the expression of CYP26A1 in SH-SY5Y cells, and treatment with R116010, but not acitretin, potentiated the RA-induced expression of a reporter gene and CYP26A1. The response of neuroblastoma cells to R116010 was consistent with inhibition of CYP26, indicating that inhibition of RA metabolism may further optimise retinoid treatment in neuroblastoma. PMID:15714209

On-line concentration and determination of all-trans- and 13-cis- retinoic acids in rabbit serum by application of sweeping technique in micellar electrokinetic chromatography.

PubMed

Zhao, Yongxi; Kong, Yu; Wang, Bo; Wu, Yayan; Wu, Hong

2007-03-30

A simple and rapid micellar electrokinetic chromatography (MEKC) method with UV detection was developed for the simultaneous separation and determination of all-trans- and 13-cis-retinoic acids in rabbit serum by on-line sweeping concentration technique. The serum sample was simply deproteinized and centrifuged. Various parameters affecting sample enrichment and separation were systematically investigated. Under optimal conditions, the analytes could be well separated within 17min, and the relative standard deviations (RSD) of migration times and peak areas were less than 3.4%. Compared with the conventional MEKC injection method, the 18- and 19-fold improvements in sensitivity were achieved, respectively. The proposed method has been successfully applied to the determination of all-trans- and 13-cis-retinoic acids in serum samples from rabbits and could be feasible for the further pharmacokinetics study of all-trans-retinoic acid.

Determination of the kinetics of degradation of 13-cis-retinoic acid and all-trans-retinoic acid in solution.

PubMed

Tan, X; Meltzer, N; Lindenbaum, S

1993-09-01

The degradations of 13-cis-retinoic acid and all-trans-retinoic acid in an organic solvent were determined with an HPLC assay. The degradation curves at 70, 50 and 37 degrees C all showed autocatalytic characteristics for both isomers. For this kind of complex reaction, the usual method cannot be used to estimate the shelf-lives and half-lives at room temperature. In this work a new method was developed to directly calculate the shelf-lives and half-lives. From this equation the activation energy was found to change as the multiple step reaction progressed.

Standard Guidelines of Care: Performing Procedures in Patients on or Recently Administered with Isotretinoin

PubMed Central

Mysore, Venkataram; Mahadevappa, Omprakash H.; Barua, Shyamanta; Majid, Imran; Viswanath, Vishalakshi; Bhat, Ramesh M.; Talwar, Suresh; Thurakkal, Salim; Aurangabadkar, Sanjeev J.; Chatterjee, Manas; Ganjoo, Anil

2017-01-01

Background: Currently, the standard protocol regarding the performance of procedures on patients receiving or having recently received isotretinoin (13-cis-retinoic acid) states that the procedures should not be performed. The recommendations in standard books and drug insert require discontinuation of isotretinoin for 6 months before performing cosmetic procedures, including waxing, dermabrasion, chemical peels, laser procedures, or incisional and excisional cold-steel surgery. These recommendations have been followed for over two decades despite little evidence for the stated increased risk of scarring. Objective: The Association of Cutaneous Surgeons (I) constituted a task force to review the evidence and to recommend consensus guidelines regarding the safety of skin procedures, including resurfacing, energy-device treatments, and dermatosurgical procedures in patients with concurrent or recent isotretinoin administration. Materials and Methods: Data were extracted from the literature through a PubMed search using the keywords “isotretinoin,” “safety,” “scarring,” “keloids,” “hypertrophic scarring,” and “pigmentation.” The evidence was then labeled and circulated to all members of task force for review. Results: The task force is of the opinion that there is insufficient evidence to support the current protocol of avoiding and delaying treatments in the patient group under consideration and recommends that the current practice should be discontinued. The task force concludes that performing procedures such as laser hair removal, fractional lasers for aging and acne scarring, lasers for pigmented skin lesions, fractional radio-frequency microneedling, superficial and medium-depth peels, microdermabrasion, dermaroller, biopsies, radio-frequency ablation, and superficial excisions is safe in patients with concurrent or recent isotretinoin administration. PMID:29491653

Analysis and stability study of retinoids in pharmaceuticals by LC with fluorescence detection.

PubMed

Gatti, R; Gioia, M G; Cavrini, V

2000-08-01

Liquid chromatographic (HPLC) methods with fluorescence detection at different wavelengths were developed for measurements of retinoic acids (13-cis and all-trans) in pharmaceutical dosage forms and components of 'retinoid solution' (all-trans retinoic acid, vitamin A palmitate and beta-carotene), a galenical of 'Di Bella therapy', using reversed phase columns under isocratic conditions. The stability of all-trans retinoic acid in cream and all-trans retinoic acid and vitamin A palmitate in 'retinoid solution' was investigated. Solid-phase extraction (SPE), using C18 sorbent was applied to the analysis of retinoic acids (9-cis, 13-cis and all-trans) in the 'retinoid solution' to obtain a practical and reliable sample clean-up. The results showed that these preparations (cream and solution) can be conveniently stored in the dark (t.a. or 2-8 degrees C): under these conditions about 86-87% of the all-trans retinoic acid initial concentration in both formulations and about 73-78% of vitamin A palmitate in the 'retinoid solution' remained after 90 days, while under sunlight exposure rapid degradation of the drugs was observed.

Kinetic properties of the human liver cytosolic aldehyde dehydrogenase for retinal isomers.

PubMed

Bhat, P V; Samaha, H

1999-01-15

Retinoic acid exerts pleiotropic effects by acting through two families of nuclear receptors, RAR and RXR. All-trans and 9-cis retinoic acid bind RARs, whereas 9-cis retinoic acid binds and activates only the RXRs. To understand the role of human liver cytosolic aldehyde dehydrogenase (ALDH1) in retinoic acid synthesis, we examined the ability of ALDH 1 to catalyze the oxidation of the naturally occurring retinal isomers. ALDH1 catalyzed the oxidation of all-trans, 9-cis, and 13-cis retinal with equal efficiency. However, the affinity to all-trans retinal (Km = 2.2 microM) was twofold higher than to 9-cis (Km = 5.5 microM) and 13-cis (Km = 4.6 microM) retinal. All-trans retinol was a potent inhibitor of ALDH1 activity, and inhibited all-trans retinal oxidation uncompetitively. Comparison of the kinetic properties of ALDH1 for retinal isomers with those of previously reported rat kidney retinal dehydrogenase showed distinct differences, suggesting that ALDH1 may play a different role in retinal metabolism in liver.

Combinational treatment with retinoic acid derivatives in non-small cell lung carcinoma in vitro.

PubMed

Choi, Eun Jung; Whang, Young Mi; Kim, Seok Jin; Kim, Hyun Jin; Kim, Yeul Hong

2007-09-01

The growth inhibitory effects of four retinoic acid (RA) derivatives, 9-cis RA, 13-cis RA, N-(4-hydroxyphenyl) retinamide (4-HPR), and all-trans retinoic acid (ATRA) were compared. In addition, the effects of various combinations of these four agents were examined on non-small cell lung carcinoma (NSCLC) cell-lines, and on the expressions of retinoic acid receptors (RARs) and retinoid X receptors (RXRs) on these cells. At the clinically achievable concentration of 1 microM, only 4-HPR inhibited the growths of H1299 and H460 cells-lines. However, retinoic acid receptor beta(RAR beta) expression was up-regulated on H460 and H1299 cells treated with 1 microM of ATRA, 13-cis RA, or 9-cis RA. All NSCLC cell lines showed growth inhibition when exposed sequentially to 1 microM ATRA and 0.1 microM 4-HPR. In particular, sequential treatment with 1 microM ATRA or 13-cis RA and 4-HPR markedly inhibited H1703 cell growth; these cells exhibited no basal RAR beta expression and were refractory to 4-HPR. However, in NSCLC cell lines that expressed RAR beta, the expressional levels of RAR beta were up-regulated by ATRA alone and by sequential treatment with ATRA and 4-HPR. 4-HPR was found to be the most active of the four agents in terms of NSCLC growth-inhibition. Moreover, sequential treatments with ATRA or 13-cis RA followed by 4-HPR were found to have synergistic growth-inhibitory effects and to regulate RAR expression.

Failure of isotretinoin and interferon-alpha combination therapy for HPV-linked severe vulvar dysplasia. A report of two cases.

PubMed

Vilmer, C; Havard, S; Cavelier-Balloy, B; Pelisse, M; Dubertret, L; Leibowitch, M

1998-08-01

Retinoids (RA) and interferon (IFN) have been reported to be active against a variety of tumors and human papillomavirus (HPV)-related lesions. Because chronic and recurrent HPV-linked vulvar intraepithelial neoplasia 3 (VIN 3) have a high risk of invasion, we evaluated combined therapy of IFN-alpha with 13-cis-retinoic acid (13 cRA) in the treatment of two VIN 3 cases of this type. Two patients with chronic and recurrent VIN 3 were treated with combined therapy of IFN-alpha (4.5 x 10(6) five times a week) and 13 cRA (1 mg/kg/d) for six months. Clinical regression was observed at the end of treatment in both cases, but histologic features of VIN 3 were still present. These data demonstrate the ineffectiveness of the combined regimen of IFN-alpha and 13 cRA with this schedule for a period of six months in recurrent and chronic VIN 3.

Effects of retinoic acids on the dendritic morphology of cultured hippocampal neurons.

PubMed

Liu, Ying; Kagechika, Hiroyuki; Ishikawa, Junko; Hirano, Hitoshi; Matsukuma, Satoshi; Tanaka, Kazuko; Nakamura, Shoji

2008-08-01

Vitamin A-derived retinoic acids (RAs) are known to exert a variety of biological actions, including modulatory effects on cell differentiation and apoptosis. A recent study has demonstrated that 13-cis-RA and all-trans-RA suppressed neurogenesis in the dentate gyrus of the hippocampus in adult mice. The present experiments were performed to see whether 13-cis-RA and all-trans-RA could alter the dendritic morphology of cultured hippocampal neurons via RA receptors: retinoic acid receptor (RAR) and retinoid X receptor (RXR). High doses of 13-cis-RA and all-trans-RA exerted a negative effect on the cultured hippocampal neurons, while a low dose of 13-cis-RA but not all-trans-RA caused a positive effect. The negative changes induced by 13-cis-RA and all-trans-RA were antagonized by RXR antagonists and RAR antagonists, respectively. The positive changes induced by a low dose of 13-cis-RA were blocked by both RXR antagonists and RAR antagonists. These results suggest that RAs at high concentrations cause a negative effect on the dendritic morphology of cultured hippocampal neurons through RA receptors, while RAs at low concentrations exert a positive influence on cultured hippocampal neurons.

The metabolism and pharmacokinetics of isotretinoin in patients with acne and rosacea are not influenced by ethanol.

PubMed

Grønhøj Larsen, F; Jakobsen, P; Grønhøj Larsen, C; Heidenheim, M; Held, E; Nielsen-Kudsk, F

2009-09-01

Isotretinoin is effective in the treatment of severe acne and rosacea. Both parent drug and its main metabolite 4-oxo-isotretinoin are potentially teratogenic compounds and contain a carboxylic acid moiety. In the presence of ethanol, naturally occurring as well as synthetic retinoids also containing a carboxylic acid moiety are capable of undergoing an ethyl esterification with the metabolic formation of more lipophilic compounds with a much longer terminal half-life. To determine if isotretinoin (13-cis-RA), its main metabolite 4-oxo-isotretinoin (4-oxo-13-cis-RA), and other possible metabolites in the presence or absence of ethanol are converted to their corresponding ethyl derivatives in patients with severe acne or rosacea after multiple isotretinoin dosing. In addition, pharmacokinetic parameters of the parent drug and its 4-oxo metabolite were determined. Eleven patients with severe acne or rosacea were treated with isotretinoin daily for 3 months and investigated pharmacokinetically during 24 h after 1 month of treatment and for up to 28 days after discontinuation of therapy. A possible influence of ethanol was evaluated using a simple self-administered questionnaire and by measuring serum ethanol levels during treatment. The concentrations of isotretinoin, 4-oxo-isotretinoin and possible ethylated and nonethylated metabolites were measured by reverse-phase high-performance liquid chromatography. Although seven of 11 patients had a considerable weekly alcohol intake, no endogenous synthesis of ethyl derivatives of isotretinoin, the main 4-oxo metabolite or the all-trans compounds was chromatographically detectable in any of the patients' plasma samples during the treatment period. Multiple dose pharmacokinetic data for the parent drug and its main metabolite were comparable to previous studies. The metabolism and pharmacokinetics of isotretinoin and its main metabolites are not influenced by ethanol during long-term isotretinoin treatment. After ceasing long-term isotretinoin therapy the recommended period of 1 month for using anticonceptive measures in fertile women seems adequate.

Improvement of cystic fibrosis during treatment with isotretinoin.

PubMed

Buckley, Jennifer L; Chastain, Mark A; Rietschel, Robert L

2006-01-01

A 15-year-old boy with a history significant for multiple respiratory infections since birth presented for evaluation of acne vulgaris. He was initially prescribed doxycycline, topical tretinoin, and topical clindamycin solution, with the later addition of a benzoyl peroxide preparation to his regimen. The patient returned 6 months later after having been diagnosed with CF (cystic fibrosis) by sweat testing and genetic testing. His skin condition had not responded adequately to prior therapy, so all acne medications were discontinued. The 84-kg patient was started on 80 mg (0.95 mg/kg/d) of isotretinoin (13-cis-retinoic acid) daily. The patient's dose was decreased to 40 mg/d 2 weeks later following an episode of blood in his stool and epistaxis. At the 1- and 2-month follow-up visits, the patient reported improvement in his acne and mentioned that his lung secretions seemed reduced. His acne cleared after 4 months of therapy, so the isotretinoin was discontinued. The patient and his mother noted that no respiratory infections had occurred during the course of therapy. The patient's acne relapsed nearly 2 years later, so isotretinoin was restarted at 60 mg/d. During the next 7 months while on the drug, he experienced no further episodes of epistaxis or bloody stools and his acne had resolved by the end of therapy. The patient and his mother again reported fewer bronchopulmonary secretions and no infections requiring antibiotics during treatment with isotretinoin. This was unusual because he had experienced numerous respiratory infections requiring antibiotics during the prior 2 years. Since discontinuing the drug, the patient has had intermittent pulmonary infections and exacerbations in the symptomatology of his CF.

Concentrations of retinoids in early pregnancy and in newborns and their mothers.

PubMed

Berggren Söderlund, Maria; Fex, Göran A; Nilsson-Ehle, Peter

2005-03-01

Retinoids are vital for embryonic development; both excesses and deficiencies of vitamin A are known to give similar patterns of birth defects. Concentrations of retinol in newborns and in pregnant women have been investigated, but concentrations of the biologically active metabolite all-trans retinoic acid and its isomer 13-cis retinoic acid have not. We measured serum concentrations of these retinoid derivatives in newborns and their mothers and in women in the first trimester of pregnancy, when embryonic differentiation (organogenesis) takes place. In this descriptive study, 10 newborns from normal deliveries and their mothers and 16 healthy women in their first trimester of pregnancy were studied. Seventeen healthy women served as control subjects. all-trans and 13-cis Retinoic acid and retinol concentrations were measured by HPLC. The newborns had significantly lower retinol concentrations (1.0 micromol/L) than did their mothers (1.7 micromol/L; P = 0.013). Serum all-trans retinoic acid was also significantly lower in the newborns (3.4 nmol/L) than in their mothers (5.8 nmol/L; P = 0.008). In addition, serum concentrations of 13-cis retinoic acid were significantly lower in the newborns (2.0 nmol/L) than in their mothers (2.6 nmol/L; P = 0.005). The serum concentrations of all-trans retinoic acid and retinol did not correlate in any group. Retinol concentrations do not accurately reflect the concentrations of the biologically active derivative all-trans retinoic acid.

Serum levels of albumin, triglycerides, total protein and glucose in rats are altered after oral treatment with low doses of 13-cis-retinoic acid or all-trans-retinoic acid.

PubMed

Cisneros, F J; Gough, B J; Patton, R E; Ferguson, S A

2005-01-01

Currently used to treat severe acne, 13-cis-retinoic acid (13-cis-RA) is under investigation for its anticancer effects as is the isomer, all-trans-retinoic acid (all-trans-RA). Here, the effects of oral 13-cis-RA or all-trans-RA treatment on serum chemistry, leptin and adiponectin levels were evaluated. Adult Sprague-Dawley rats were gavaged once daily for 7 consecutive days with 13-cis-RA (7.5 or 15 mg kg(-1)), all-trans-RA (10 or 15 mg kg(-1)) (n=24/sex/dose), or soy oil (n=16/sex) and blood was sampled 30-480 min after the last gavage. The body weight was unaffected; however, the liver/body weight ratios were increased by both doses of all-trans-RA. Sex differences were noted for levels of cholesterol, creatine, triglycerides, albumin, alanine aminotransferase and total protein. Both doses of all-trans-RA reduced albumin levels to approximately 90% of the control and total protein levels to approximately 93% of the control while substantially elevating triglyceride levels to approximately 66%-99% above the control. Additionally, triglyceride levels of the 15 mg kg(-1) 13-cis RA group were approximately 62% higher than the controls and total protein levels were approximately 5% less. Glucose levels were affected by sex and RA treatment in that males treated with 15 mg kg(-1) of 13-cis-RA or 10 mg kg(-1) all-trans-RA had lower (13%-19%) levels than the same-sex controls; however, females were not similarly affected. Neither 13-cis-RA nor all-trans-RA treatment had significant effects on the levels of blood urea nitrogen, aspartate amino transferase, leptin or adiponectin. On a mg kg(-1) basis, all-trans-RA was more potent than 13-cis-RA. These results replicate previous findings of RA-induced increased triglyceride levels. Additionally, several new findings indicate there may be sex-specific effects of RA treatment. Finally, neither treatment appeared to alter the typical diurnal cycles of these endpoints. Copyright (c) 2005 John Wiley & Sons, Ltd.

[Isotretinoin embryopathy. Report of one case].

PubMed

Troncoso Sch, Mónica; Rojas H, Carla; Bravo C, Eduardo

2008-06-01

Retinoic acid is a widely used drug in the treatment of cystic acne. It has teratogenic effects that depend on the gestational period in which it is used. We report a seven months old female whose mother was exposed to retinoic acid in both pre-gestational and gestational periods. She had a retardation of psychomotor development and a brain MRI showed frontal atrophy and a malformation of the posterior fossa. We discuss the mechanisms of the teratogenic effects of retinoic acid.

Supercritical fluid extraction of 13-cis retinoic acid and its photoisomers from selected pharmaceutical dosage forms.

PubMed

Simmons, B R; Chukwumerije, O; Stewart, J T

1997-11-01

13-Cis retinoic acid (Accutane) was extracted from a cream, gel, capsule and beadlet dosage from using supercritical carbon dioxide modified with 5% methanol as the mobile phase. The pump pressure and the extraction chamber and restrictor temperature were experimentally optimized at 325 atm and 45 degrees C, respectively. A 2.5-min static and 5-min dynamic extraction time were used. The supercritical fluid extraction (SFE) eluent was trapped in methanol, injected into the high-performance liquid chromatographic (HPLC) system, and quantitated by ultraviolet detection at 360 nm. Application of the SFE method to spiked placebo dosage forms gave 13-cis retinoic acid recoveries of 98.8, 98.9, 98.8 and 100% for the cream, gel, capsule and beadlet, respectively, with R.S.D.s in the range 0.6-0.9% (n = 4). Inter-day percent error and precision of the extraction were 1.1-2.0 and 0.2-2.4% (n = 3), respectively, and intra-day percent error and precision were 1.0-3.0 and 0.3-2.1% (n = 8), respectively. Percent error and precision data for spiked celite samples in the 0.05-1.0 microgram ml-1 range were 0.59-4.75 and 1.8-2.1% (n = 3), respectively. The extraction method was applied to commercial 13-cis retinoic acid dosage forms and the results compared to unextracted samples. Linear regression analysis of concentration versus peak height gave a correlation coefficient of 0.9991 with a slope of 7.468 and a y-intercept of 0.1923. The percent error and precision data were 1.3-5.3 and 0.2-1.5% (n = 4), respectively. The photoisomers of 13-cis retinoic acid were also extracted with the method and recoveries of 90.4-92.4% with R.S.D.s of 1.5-3.4% were obtained (n = 4).

HPLC, MS, and pharmacokinetics of melphalan, bisantrene and 13-cis retinoic acid.

PubMed

Davis, T P; Peng, Y M; Goodman, G E; Alberts, D S

1982-11-01

High performance liquid chromatographic procedures are described for melphalan, bisantrene, and 13-cis retinoic acid, three important anticancer drugs in various stages of clinical development. The procedures require a rapid and simple sample clean-up followed by a 10-to 20-min chromatographic separation on a reversed-phase C18 column. Precisions are all less than 8% with recoveries greater than 80%. Mass spectrometry confirmation of each drug from patient sample separations is presented to provide unambiguous identification for valid pharmacokinetic parameter determination.

In vitro interaction study of retinoic acid isomers with telmisartan and amlodipine by equilibrium dialysis method using UV spectroscopy

NASA Astrophysics Data System (ADS)

Varghese, Susheel John; Johny, Sojimol K.; Paul, David; Ravi, Thengungal Kochupappy

2011-07-01

The in vitro protein binding of retinoic acid isomers (isotretinoin and tretinoin) and the antihypertensive drugs (amlodipine and telmisartan) was studied by equilibrium dialysis method. In this study, free fraction of drugs and the % of binding of drugs in the mixture to bovine serum albumin (BSA) were calculated. The influence of retinoic acid isomers on the % of protein binding of telmisartan and amlodipine at physiological pH (7.4) and temperature (37 ± 0.5 °C) was also evaluated. The in vitro displacement interaction study of drugs telmisartan and amlodipine on retinoic acid isomers and also interaction of retinoic acid isomers on telmisartan and amlodipine were carried out.

Age-related change in the retinoid X receptor beta gene expression in peripheral blood mononuclear cells of healthy volunteers: effect of 13-cis retinoic acid supplementation.

PubMed

Brtko, J; Rock, E; Nezbedova, P; Krizanova, O; Dvorcakova, M; Minet-Quinard, R; Farges, M-C; Ribalta, J; Winklhofer-Roob, B M; Vasson, M-P; Macejova, D

2007-01-01

The regulation of cell growth and differentiation and also expression of a number of genes by retinoids are mediated by nuclear retinoid receptors (RARs and/or RXRs). In this study we investigated age-related alteration in both RAR and RXR receptor subtypes gene expression and tissue transglutaminase (tTG) activity before and after supplementation with 13-cis retinoic acid (13cRA) in human peripheral blood mononuclear cells (PBMCs). Healthy men (40) were divided in two groups according to their age (young group: 26.1+/-4.1 years and old group: 65.4+/-3.8 years). Each volunteer received 13cRA (Curacné), 0.5mg/(kgday)) during a period of 4 weeks. We have shown that RXRbeta expression was decreased significantly (p=0.0108) in PBMCs of elderly men when compared to that of young volunteers. Distribution of retinoic acid receptor subtype expression in PBMCs was found in the order: RXRbeta>RARgamma>RXRalpha>RARalpha. The tTG activity in PBMCs reflected a trend to be enhanced after 13-cis retinoic acid supplementation. In conclusion, we demonstrate a significant decrease in the expression of RXRbeta subtype of rexinoid receptors in PBMCs of healthy elderly men. Our data suggest that in healthy elderly men reduction of RXRbeta expression in PBMCs might be a common feature of physiological senescence.

Low-dose retinoic acid enhances in vitro invasiveness of human oral squamous-cell-carcinoma cell lines

PubMed Central

Uchida, D; Kawamata, H; Nakashiro, K; Omotehara, F; Hino, S; Hoque, M O; Begum, N-M; Yoshida, H; Sato, M; Fujimori, T

2001-01-01

Retinoids inhibit the proliferation of several types of tumour cells, and are used for patients with several malignant tumours. In this study, we examined the effect of retinoic acids (RAs) on the invasive potentials of the oral squamous cell carcinoma (SCC) cells, BHY and HNt. BHY cells expressed all of retinoid nuclear receptors (RARα, β, γ, and RXRα) and cytoplasmic retinoic acid binding proteins (CRABP1 and CRABP2). HNt cells lacked the expression of RARβ, but expressed other nuclear receptors and CRABPs. All-trans retinoic acid (ATRA) and 13-cis retinoic acid (13-cisRA) (10−6and 10−7M) inhibited the growth of the cells, but low-dose ATRA and 13-cisRA (10−8M) marginally affected the growth of the cells. Surprisingly, low-dose RAs enhanced the activity of tissue-type plasminogen activator (tPA), and activated pro-matrix metalloproteinases (proMMP2 and proMMP9). Activation of proMMP2 and proMMP9 was inhibited by aprotinin, a serine-proteinase, tPA inhibitor. Furthermore, low-dose RAs enhanced the in vitro invasiveness of BHY cells. These results indicate that low-dose RAs enhances the in vitro invasiveness of oral SCC cells via an activation of proMMP2 and proMMP9 probably mediated by the induction of tPA. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11437413

[Plasma level and metabolism of vitamin A (Vitadral) in women of reproductive age].

PubMed

Peiker, G; Eckhoff, C; Nau, H

1991-01-01

Using a sensitive HPLC method, plasma concentrations of vitamin A and metabolites were measured from 6 female volunteers who had taken once daily 0.46 mg/kg BW retinol palmitate (Vitadral) for 10 days. The metabolites all-trans- and 13-cis-retinoic acid were increased significantly (2- and 5-fold, resp.) 6 h after the ist intake. 13-cis-4-oxo retinoic acid the 10th intake in the morning of the 10th day (9.22 +/- 2.77 ng/ml, 4-fold increase). The results show continuous increase of retinoic acids, which have to be considered as potential teratogens, after administration of vitamin A. The plasma concentration of retinol itself did not change, whereas only short-term increases were observed for retinol esters.

Retinoic Acid Isomers Up-Regulate ATP Binding Cassette A1 and G1 and Cholesterol Efflux in Rat Astrocytes: Implications for Their Therapeutic and Teratogenic Effects

PubMed Central

Chen, Jing; Costa, Lucio G.

2011-01-01

Recent studies suggest that retinoids may be effective in the treatment of Alzheimer's disease, although exposure to an excess of retinoids during gestation causes teratogenesis. Cholesterol is essential for brain development, but high levels of cholesterol have been associated with Alzheimer's disease. We hypothesized that retinoic acid may affect cholesterol homeostasis in rat astrocytes, which regulate cholesterol distribution in the brain, through the up-regulation of cholesterol transporters ATP binding cassette (Abc)a1 and Abcg1. Tretinoin, 13-cis retinoic acid (13-cis-RA), 9-cis-RA, and the selective retinoid X receptor (RXR) agonist methoprene significantly increased cholesterol efflux induced by cholesterol acceptors and protein levels of Abca1 by 2.3- (±0.25), 3.6- (±0.42), 4.1- (±0.5), and 1.75- (±0.43) fold, respectively, and Abcg1 by 2.1- (±0.26), 2.2- (±0.33), 2.5- (±0.23), and 2.2- (±0.21) fold, respectively. 13-cis-RA and 9-cis-RA also significantly increased mRNA levels of Abca1 (maximal induction 7.3 ± 0.42 and 2.7 ± 0.17, respectively) and Abcg1 (maximal induction 2.0 ± 0.18 and 1.8 ± 0.09, respectively), and the levels of membrane-bound Abca1 (2.5 ± 0.3 and 2.5 ± 0.40-fold increase, respectively), whereas they significantly decreased intracellular cholesterol content without affecting cholesterol synthesis. The effect of 9-cis-RA on cholesterol homeostasis in astrocytes can be ascribed to the activation of RXR, whereas the effects of 13-cis-RA and tretinoin were independent of either RXRs or retinoic acid receptors. These findings suggest that retinoids affect cholesterol homeostasis in astrocytes and that this effect may be involved in both their therapeutic and teratogenic actions. PMID:21628419

Chronic treatment with 13-cis-retinoic acid changes aggressive behaviours in the resident-intruder paradigm in rats.

PubMed

Trent, Simon; Drew, Cheney J G; Mitchell, Paul J; Bailey, Sarah J

2009-12-01

Retinoids, vitamin A related compounds, have an established role in the development of the nervous system and are increasingly recognized to play a role in adult brain function. The synthetic retinoid, 13-cis-retinoic acid (13-cis-RA, Roaccutane) is widely used to treat severe acne but has been linked to an increased risk of neuropsychiatric side effects, including depression. Here we report that chronic administration with 13-cis-RA (1 mg/kg i.p. daily, 7-14 days) in adult rats reduced aggression- and increased flight-related behaviours in the resident-intruder paradigm. However, in the forced swim, sucrose consumption and open field tests treatment for up to 6 weeks with 13-cis-RA did not modify behaviour in adult or juvenile animals. The behavioural change observed in the resident-intruder paradigm is directly opposite to that observed with chronic antidepressant administration. These findings indicate that when a suitably sensitive behavioural test is employed then chronic administration of 13-cis-RA in adult rats induces behavioural changes consistent with a pro-depressant action.

In vitro interaction study of retinoic acid isomers with telmisartan and amlodipine by equilibrium dialysis method using UV spectroscopy.

PubMed

Varghese, Susheel John; Johny, Sojimol K; Paul, David; Ravi, Thengungal Kochupappy

2011-07-01

The in vitro protein binding of retinoic acid isomers (isotretinoin and tretinoin) and the antihypertensive drugs (amlodipine and telmisartan) was studied by equilibrium dialysis method. In this study, free fraction of drugs and the % of binding of drugs in the mixture to bovine serum albumin (BSA) were calculated. The influence of retinoic acid isomers on the % of protein binding of telmisartan and amlodipine at physiological pH (7.4) and temperature (37±0.5°C) was also evaluated. The in vitro displacement interaction study of drugs telmisartan and amlodipine on retinoic acid isomers and also interaction of retinoic acid isomers on telmisartan and amlodipine were carried out. Copyright © 2011 Elsevier B.V. All rights reserved.

Crystal structures of substrate-free and retinoic acid-bound cyanobacterial cytochrome P450 CYP120A1.

PubMed

Kühnel, Karin; Ke, Na; Cryle, Max J; Sligar, Stephen G; Schuler, Mary A; Schlichting, Ilme

2008-06-24

The crystal structures of substrate-free and all-trans-retinoic acid-bound CYP120A1 from Synechocystis sp. PCC 6803 were determined at 2.4 and 2.1 A resolution, respectively, representing the first structural characterization of a cyanobacterial P450. Features of CYP120A1 not observed in other P450 structures include an aromatic ladder flanking the channel leading to the active site and a triple-glycine motif within SRS5. Using spectroscopic methods, CYP120A1 is shown to bind 13-cis-retinoic acid, 9-cis-retinoic acid, and retinal with high affinity and dissociation constants of less than 1 microM. Metabolism of retinoic acid by CYP120A1 suggests that CYP120A1 hydroxylates a variety of retinoid derivatives in vivo. On the basis of the retinoic acid-bound CYP120A1 crystal structure, we propose that either carbon 2 or the methyl groups (C16 or C17) of the beta-ionone ring are modified by CYP120A1.

Pharmacokinetics of 13-cis-retinoic acid in patients with advanced cancer.

PubMed

Goodman, G E; Einspahr, J G; Alberts, D S; Davis, T P; Leigh, S A; Chen, H S; Meyskens, F L

1982-05-01

13-cis-Retinoic acid (13-CRA) is a synthetic analog of vitamin A effective reversing preneoplastic lesions in both humans and animals. To study its physiochemical properties and disposition kinetics, we developed a rapid, sensitive, and precise high-performance liquid chromatography assay for 13-CRA in biological samples. This assay system resulted in a clear separation of 13-CRA from all-trans-retinoic acid and retinol and had a detection limit of 20 ng/ml plasma. Recovery was 89 +/- 6% (S.D.) at equivalent physiological concentrations with a precision of 8%. To study the disposition kinetics in humans, 13 patients received a p.o. bolus of 13-CRA and had blood samples collected at timed intervals. For the 10 patients studied on the first day of 13-CRA administration, the mean time to peak plasma concentration was 222 +/- 102 min. Interpatient peak 13-CRA plasma concentrations were found to be variable, suggesting irregular gastrointestinal absorption. Beta-Phase t 1/2 was approximately 25 hr. The prolonged terminal-phase plasma half-life may represent biliary excretion and enterohepatic circulation.

Effect of isotretinoin on tooth germ and palate development in mouse embryos.

PubMed

Balducci-Roslindo, E; Silvério, K G; Jorge, M A; Gonzaga, H F

2001-01-01

Vitamin A and its derivatives, retinoic acid, tretinoin and isotretinoin, are currently used in dermatological treatments. The administration of high doses of this vitamin provokes congenital malformations in mice: cleft palate, maxillary and mandibular hypoplasia and total or partial fusion of the maxillary incisors. This study compares the tooth germs of the first maxillary and mandibular molars of fetal mice submitted to isotretinoin during organogenesis. Twelve 60-day-old female Mus musculus were divided into two groups on the 7th day of pregnancy: treated group--1 mg isotretinoin per kg body weight, dissolved in vegetable oil, was administered from the 7th to the 13th day of pregnancy; control group--vegetable oil in equivalent volume was administered orally for the same period. On the 16th day of pregnancy, the females were sacrificed, the fetuses were removed and their heads amputated. After standard laboratory procedures, 6-micron thick serial slices were stained with hematoxylin and eosin for optical microscopy examination. The results showed that both groups had closed palates with no reminiscence of epithelial cells; however, the first molar germs of the isotretinoin-treated animals showed delayed development compared to the control animals.

Lipid peroxide, alpha-tocopherol and retinoid levels in plasma and liver of rats fed diets containing beta-carotene and 13-cis-retinoic acid.

PubMed

Alam, S Q; Alam, B S

1983-12-01

The effect of feeding large amounts of beta-carotene and 13-cis-retinoic acid (RA) on plasma and liver levels of alpha-tocopherol, lipid peroxides and retinoids was studied. Groups of young male rats were fed semipurified diets supplemented with 0, 100 mg/kg beta-carotene, 20 and 100 mg/kg 13-cis-RA. After feeding the various diets for 11 weeks, rats were killed and the concentrations of lipid peroxides, alpha-tocopherol, and retinoids were measured in blood plasma and liver. Peroxide levels were increased and alpha-tocopherol levels were decreased in plasma as well as liver of rats fed diets containing 13-cis-RA; this effect seems to be dose dependent, beta-Carotene had no significant effect on either of the above parameters. There was a decrease in the liver and plasma concentrations of retinol in rats fed 13-cis-RA; the levels of RA were generally higher in these two groups. The results suggest that the mechanism whereby 13-cis-RA increases the tissue peroxide levels may be related to its ability to decrease alpha-tocopherol levels.

Teratogenicity and transplacental pharmacokinetics of 13-cis-retinoic acid in rabbits.

PubMed

Eckhoff, C; Chari, S; Kromka, M; Staudner, H; Juhasz, L; Rudiger, H; Agnish, N

1994-03-01

No embryotoxic or teratogenic effects, considered to be treatment related, were observed in rabbits after daily oral doses of 3 mg/kg of 13-cis-retinoic acid (13-cis-RA) from Day 8 to Day 11 of gestation. In contrast, treatment with 15 mg/kg/day significantly increased the rate of fetal resorptions (22%) and 13 out of 68 surviving fetuses (16%) were malformed. Pharmacokinetic studies with both dosing regimens of 13-cis-RA in pregnant rabbits showed that on Day 11 of gestation, high concentrations of parent compound, 13-cis-RA, and its major metabolite, 13-cis-4-oxoRA, existed in maternal plasma. Much lower concentrations were found for all-trans-4-oxoRA and all-trans-RA. The area under the concentration-time curve (AUC) of all-trans-RA following the 15 mg/kg/day dosing regimen of 13-cis-RA was only 1.2% that of parent compound 13-cis-RA. At this dose, embryo levels of 13-cis-RA, 13-cis-4-oxoRA, and all-trans-4-oxoRA were 2.5-, 4.7-, and 3.6-fold higher by AUC comparison (24-hr period of Day 11) compared with the dose of 3 mg/kg. However, embryo levels of all-trans-RA were virtually identical at both doses and were, in fact, somewhat lower than endogenous concentrations measured in untreated rabbit embryos. In contrast to mice, where isomerization from 13-cis- to all-trans-RA was suggested to be crucial for the teratogenic action of 13-cis-RA, we found that the teratogenic action of 13-cis-RA (15 mg/kg/day) in rabbits is characterized by increased whole embryo concentrations of 13-cis-RA, 13-cis-4-oxoRA, and all-trans-4-oxoRA, but not of all-trans-RA.

Selected retinoids: determination by isocratic normal-phase HPLC.

PubMed

Klvanova, J; Brtko, J

2002-09-01

Retinol (ROL), retinal (RAL) and retinoic acid (RA) are physiologically active forms of vitamin A. All-trans retinoic acid (ATRA) can be formed by oxidation from all-trans retinal (ATRAL). Isomerization of RA is considered to be an important metabolic pathway of retinoids. RA isomers transactivate various response pathways via their cognate nuclear receptors that act as ligand inducible transcription factors. The aim of this study was to establish a rapid and simple method for determination of ATRA, 13-cis retinoic acid (13CRA) and ATRAL by HPLC. In our laboratory, we slightly modified the method of Miyagi et al. (2001) and separated ATRA, 13CRA and ATRAL by simple isocratic normal phase HPLC. Both retinoic acid isomers and ATRAL were eluted within 13 min and all components were well resolved. The coefficients of variation (C.V.) for RAs and RAL were from 3.0 to 5.4 %.

Recombinant human glutathione S-transferases catalyse enzymic isomerization of 13-cis-retinoic acid to all-trans-retinoic acid in vitro.

PubMed Central

Chen, H; Juchau, M R

1998-01-01

The steric conversion of 13-cis-retinoic acid (13-cRA) to all-trans-retinoic acid (t-RA) has been proposed as an activation mechanism for the observed therapeutic and teratogenic activities of 13-cRA. Here we have investigated the catalysis of isomerization of 13-cRA to t-RA by recombinant human glutathione S-transferases (GSTs). Substrate was incubated with GST in 0.1 M sodium phosphate buffer, pH 7.5, at 37 degrees C in total darkness. The t-RA generated was measured quantitatively by HPLC. Under the reaction conditions used, GSTP1-1 was far more effective than human GSTM1-1 or human GSTA1-1 in catalysing the isomerization reaction. The reaction catalysed by GSTP1-1 showed substrate saturation and the Km and Vmax values for the reaction were approx. 7 microM and 650 pmol/min per nmol respectively. The reaction rate increased linearly with increasing enzyme concentration. The reaction was inhibited both by heat treatment and by S-decylglutathione (a potent inhibitor of transferase activity associated with GST). Additions of polyclonal rabbit antiserum for human GSTP1-1 to the reaction resulted in a significant decrease in generation of t-RA (70-80%). In addition, ethacrynic acid, a selective substrate for Pi isoforms of GST, also inhibited the isomerization of 13-cRA to t-RA catalysed by GSTP1-1. Under the same reaction conditions, GSTP1-1 was much less effective in catalysing the steric conversion of 9-cis-retinoic acid to t-RA, indicating that the enzyme was stereospecific for the conversion of 13-cRA to t-RA. These observations suggest that enzymic catalysis was the primary mechanism for the GSTP1-1-dependent conversion of 13-cRA to t-RA. Reactions catalysed by a purified rat hepatic GST Pi isoenzyme proceeded more slowly than reactions catalysed by human GSTP1-1. Comparative studies also showed that there were marked species differences in catalytic activities between various purified mammalian hepatic GST mixtures. PMID:9806904

Recombinant human glutathione S-transferases catalyse enzymic isomerization of 13-cis-retinoic acid to all-trans-retinoic acid in vitro.

PubMed

Chen, H; Juchau, M R

1998-11-15

The steric conversion of 13-cis-retinoic acid (13-cRA) to all-trans-retinoic acid (t-RA) has been proposed as an activation mechanism for the observed therapeutic and teratogenic activities of 13-cRA. Here we have investigated the catalysis of isomerization of 13-cRA to t-RA by recombinant human glutathione S-transferases (GSTs). Substrate was incubated with GST in 0.1 M sodium phosphate buffer, pH 7.5, at 37 degrees C in total darkness. The t-RA generated was measured quantitatively by HPLC. Under the reaction conditions used, GSTP1-1 was far more effective than human GSTM1-1 or human GSTA1-1 in catalysing the isomerization reaction. The reaction catalysed by GSTP1-1 showed substrate saturation and the Km and Vmax values for the reaction were approx. 7 microM and 650 pmol/min per nmol respectively. The reaction rate increased linearly with increasing enzyme concentration. The reaction was inhibited both by heat treatment and by S-decylglutathione (a potent inhibitor of transferase activity associated with GST). Additions of polyclonal rabbit antiserum for human GSTP1-1 to the reaction resulted in a significant decrease in generation of t-RA (70-80%). In addition, ethacrynic acid, a selective substrate for Pi isoforms of GST, also inhibited the isomerization of 13-cRA to t-RA catalysed by GSTP1-1. Under the same reaction conditions, GSTP1-1 was much less effective in catalysing the steric conversion of 9-cis-retinoic acid to t-RA, indicating that the enzyme was stereospecific for the conversion of 13-cRA to t-RA. These observations suggest that enzymic catalysis was the primary mechanism for the GSTP1-1-dependent conversion of 13-cRA to t-RA. Reactions catalysed by a purified rat hepatic GST Pi isoenzyme proceeded more slowly than reactions catalysed by human GSTP1-1. Comparative studies also showed that there were marked species differences in catalytic activities between various purified mammalian hepatic GST mixtures.

Stimulation of Phospholipid Scrambling of the Erythrocyte Membrane by 9-Cis-Retinoic Acid.

PubMed

Abed, Majed; Alzoubi, Kousi; Lang, Florian; Al Mamun Bhuayn, Abdulla

2017-01-01

The endogenous retinoid 9-cis-retinoic acid has previously been shown to trigger apoptosis in a wide variety of cells including several tumor cells and has thus been suggested for the treatment of malignancy. Similar to apoptosis of nucleated cells, erythrocytes may enter suicidal erythrocyte death or eryptosis, which is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Cellular mechanisms participating in the accomplishment of eryptosis include increase of cytosolic Ca2+ activity ([Ca2+]i) and formation of ceramide. The present study explored, whether 9-cis-retinoic acid induces eryptosis and whether the effect involves Ca2+ and/or ceramide. Flow cytometry was employed to estimate erythrocyte volume from forward scatter, phosphatidylserine exposure at the cell surface from annexin-V-binding, [Ca2+]i from Fluo3-fluorescence, and ceramide abundance utilizing specific antibodies. Hemolysis was quantified from hemoglobin concentration in the supernatant. A 48 hours exposure of human erythrocytes to 9-cis-retinoic acid (≥ 0.5 µg/ml) significantly increased the percentage of annexin-V-binding cells and significantly decreased forward scatter. Exposure to 9-cis-retinoic acid (≥ 0.5 µg/ml) significantly increased Fluo3-fluorescence, and the effect of 9-cis-retinoic acid on annexin-V-binding was significantly blunted by removal of extracellular Ca2+. Exposure to 9-cis-retinoic acid (1 µg/ml) further significantly increased the ceramide abundance at the erythrocyte surface and significantly increased hemolysis. 9-cis-retinoic acid triggers phospholipid scrambling of the erythrocyte cell membrane, an effect at least in part downstream of Ca2+ and ceramide. © 2017 The Author(s)Published by S. Karger AG, Basel.

Visual pigments. 11. Spectroscopy and photophysics of retinoic acids and all-trans-methyl retinoate. [Photophysical properties at 77/sup 0/K

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takemura, T.; Chihara, K.; Becker, R.S.

1980-04-09

The photophysics of hydrogen-bonded complexes of retinoic acid and its 9-cis and 13-cis isomers and the photophysics of the dimers of these isomers of retinoic acid were studied. The investigation indicated that complexes of retinoic acid and molecules that form hydrogen bonds with the carbonyl oxygen of retinoic acid (type I complexes) have both higher radiative and nonradiative rate constants than do hydrogen-bonded complexes of retinoic acid and molecules that form hydrogen bonds only with the hydroxyl oxygen of retinoic acid (type II complexes). For all-trans-retinoic acid in 3-methylpentane at 77 K, the type I complexes have radiative rate constantsmore » approximately equal to or greater than 2 x 10/sup 8/ s/sup -1/ and nonradiative rate constants greater than 3 x 10/sup 8/ s/sup -1/. Both the radiative and nonradiative rate constants of the type II complexes of all-trans-retinoic acid at 77 K in 3-methylpentane are less than 1 x 10/sup 8/ s/sup -1/. The dimer of retinoic acid (K(association) = 1 x 10/sup 4/ M/sup -1/ at room temperature for the all-trans isomer) behaves like a type I complex, and its excited-state properties are better understood in terms of hydrogen bonding than in terms of an exciton model. The photophysical properties and triplet-triplet absorption spectrum of methyl retinoate were measured. The study concluded with an examination of some of the implications of this work for the role of hydrogen bonding in the dimers and monomers of retinal and retinol.« less

9-cis Retinoic Acid is the ALDH1A1 Product that Stimulates Melanogenesis

PubMed Central

Paterson, Elyse K.; Ho, Hsiang; Kapadia, Rubina; Ganesan, Anand K.

2013-01-01

Aldehyde dehydrogenase 1A1 (ALDH1A1), an enzyme that catalyzes the conversion of lipid aldehydes to lipid carboxylic acids, plays pleiotropic roles in UV-radiation resistance, melanogenesis, and stem cell maintenance. In this study, a combination of RNAi and pharmacologic approaches were used to determine which ALDH1A1 substrates and products regulate melanogenesis. Initial studies revealed that neither the UV-induced lipid aldehyde 4-hydroxy-2-nonenal nor the ALDH1A1 product all-trans retinoic acid appreciably induced melanogenesis. In contrast, both the ALDH1A1 substrate 9-cis retinal and its corresponding product 9-cis retinoic acid potently induced the accumulation of MITF mRNA, Tyrosinase mRNA, and melanin. ALDH1A1 depletion inhibited the ability of 9-cis retinal but not 9-cis retinoic acid to stimulate melanogenesis, indicating that ALDH1A1 regulates melanogenesis by catalyzing the conversion of 9-cis retinal to 9-cis retinoic acid. The addition of potent ALDH1A inhibitors (cyanamide or Angeli’s salt) suppressed Tyrosinase and MITF mRNA accumulation in vitro and also melanin accumulation in skin equivalents, suggesting that 9-cis retinoids regulate melanogenesis in the intact epidermis. Taken together, these studies not only identify cyanamide as a potential novel treatment for hyperpigmentary disorders, but also identify 9-cis retinoic acid as a pigment stimulatory agent that may have clinical utility in the treatment of hypopigmentary disorders, such as vitiligo. PMID:23489423

Antagonism of cytotoxic chemotherapy in neuroblastoma cell lines by 13-cis-retinoic acid is mediated by the anti-apoptotic Bcl-2 family proteins

PubMed Central

Hadjidaniel, Michael Daniel; Reynolds, Charles Patrick

2010-01-01

13-cis-retinoic acid (13-cis-RA), is given at completion of cytotoxic therapy to control minimal residual disease in neuroblastoma. We investigated the effect of combining 13-cis-RA with cytotoxic agents employed in neuroblastoma therapy using a panel of 6 neuroblastoma cell lines. The effect of 13-cis-RA on the mitochondrial apoptotic pathway, was studied by flow cytometry, cytotoxicity by DIMSCAN, and protein expression by immuoblotting. Pre-treatment and direct combination of 13-cis-RA with etoposide, topotecan, cisplatin, melphalan, or doxorubicin markedly antagonized the cytotoxicity of those agents in 4 out of 6 tested neuroblastoma cell lines, increasing fractional cell survival by 1 to 3 logs. The inhibitory concentration of drugs (IC99) increased from clinically achievable levels to non-achievable levels: > 5-fold (cisplatin) to > 7-fold (etoposide). In SMS-KNCR neuroblastoma cells, 13-cis-RA upregulated expression of Bcl-2 and Bcl-xL RNA and protein, and this was associated with protection from etoposide-mediated apoptosis at the mitochondrial level. A small molecule inhibitor of the Bcl-2 family of proteins (ABT-737) restored mitochondrial membrane potential loss and apoptosis in response to cytotoxic agents in 13-cis-RA treated cells. Prior selection for resistance to RA did not diminish the response to cytotoxic treatment. Thus, combining 13-cis-RA with cytotoxic chemotherapy significantly reduced the cytotoxiciity for neuroblastoma in vitro, mediated at least in part via the anti-apoptotic Bcl-2 family of proteins. PMID:21159604

Pharmacokinetics and metabolism of all-trans- and 13-cis-retinoic acid in pulmonary emphysema patients.

PubMed

Muindi, Josephia R; Roth, Michael D; Wise, Robert A; Connett, John E; O'Connor, George T; Ramsdell, Joe W; Schluger, Neil W; Romkes, Marjorie; Branch, Robert A; Sciurba, Frank C

2008-01-01

Retinoids promote lung alveolarization in animal models and were administered to patients as part of the Feasibility of Retinoid Therapy for Emphysema (FORTE) study. This FORTE substudy investigated the pharmacokinetic profiles of 2 retinoic acid isomers-all-trans-retinoic acid (ATRA) and 13-cis-retinoic acid (13-cRA)-in subjects with emphysema, evaluated strategies to overcome self-induced ATRA catabolism, and identified pharmacodynamic relationships. Comprehensive and limited pharmacokinetics were obtained at multiple visits in emphysema subjects treated with placebo (n = 30), intermittent dosing (4 days/week) with low-dose ATRA (1 mg/kg/day, n = 21), or high-dose ATRA (2 mg/kg/day, n = 25) or daily administration of 13-cRA (1 mg/kg/day, n = 40). High-dose ATRA produced the highest peak plasma ATRA Cmax. However, at follow-up, plasma ATRA C(max) was significantly decreased from baseline in subjects whose day 1 levels exceeded 100 ng/mL (P < .0001). In contrast, administration of 13-cRA produced lower plasma ATRA C(max) (<100 ng/mL), but the levels were significantly higher at follow-up than those on day 1 (P < .001). Plasma ATRA levels as determined on day 1 correlated with changes in pulmonary diffusing capacity at 6 months, consistent with concentration-dependent biologic effects (r2 = -0.25). The authors conclude that intermittent therapy with high-dose ATRA produced the greatest ATRA exposure, but alternative approaches for limiting self-induced ATRA catabolism should be sought.

Plasma retinoids concentration in Leptodactylus chaquensis (Amphibia: Leptodactylidae) from rice agroecosystems, Santa Fe province, Argentina.

PubMed

Teglia, Carla M; Attademo, Andrés M; Peltzer, Paola M; Goicoechea, Héctor C; Lajmanovich, Rafael C

2015-09-01

Retinoids are known to regulate important processes such as differentiation, development, and embryogenesis of vertebrates: Alteration in endogenous retinoids concentration is linked with teratogenic effects. Retinol (ROH), retinoid acid (RA), and isoform 13-Cis-retinoic acid (13-Cis-RA), in plasma of a native adults frog, Leptodactylus chaquensis from a rice field (RF) and a forest (reference site; RS) were measured. ROH did not vary between treatment sites. RA and 13-Cis-RA activities were higher (93.7±8.6 μg mL(-1) and 131.7±11.4 μg mL(-1), respectively) in individuals collected from RF than in those from RS (65.5±8.6 μg mL(-1) and 92.2±10.2 μg mL(-1), respectively). The ratios retinoic acid-retinol (RA/ROH) and 13-Cis-RA/ROH revealed significantly higher values in RF than in RS. RA and 13-Cis-RA concentrations in plasma on wild amphibian's species such as L. chaquensis would be suitable biomarkers of pesticide exposure in field monitoring. Finally, the mechanism of alteration in retinoid metabolites alteration should be further explored both in larvae and adult, considering that the potential exposition and uptake contaminants vary between the double lives of these vertebrates. Copyright © 2015 Elsevier Ltd. All rights reserved.

Retinoids, carotenoids, and tocopherols in breast adipose tissue and serum of benign breast disease and breast cancer patients

USDA-ARS?s Scientific Manuscript database

Various retinoic acid (RA) isomers (all-trans, 13-cis, 11-cis, and 9-cis) as well as retinol, carotenoids, and tocopherol concentrations were determined in both serum and breast adipose tissue of 22 benign breast disease patients and 52 breast cancer patients categorized into 4 stages by malignancy....

Glutathione S-transferases act as isomerases in isomerization of 13-cis-retinoic acid to all-trans-retinoic acid in vitro.

PubMed Central

Chen, H; Juchau, M R

1997-01-01

A discovery that rapid enzymic isomerization of 13-cis-retinoic acid (13-cRA) to all-trans-retinoic acid (t-RA) can be catalysed by purified hepatic glutathione S-transferases (GSTs; EC 2.5.1.18) from rat is now reported. Rates of cis-trans isomerization were determined quantitatively by HPLC. GST-catalysed reactions reached equilibrium rapidly, in marked contrast with uncatalysed or GSH-catalysed isomerizations. The GST-catalysed reaction exhibited substrate saturation kinetics with a Km of approx. 8 microM. The maximal velocity of the reaction and the catalytic efficiency of GSTs were determined. The initial rate of the reaction increased linearly as a function of enzyme concentration. Catalysis by GSTs was independent of the presence of GSH, indicating that GSTs act as GSH-independent isomerases as well as transferases. Incubation with guanidine (7-8 M) or heat-inactivation of GSTs (100 degrees C for 3 min) decreased isomerase activities by approx. 50% and 75% respectively. The same heat treatment did not significantly inhibit isomerization catalysed by GSH and apoferritin, indicating that the observed decrease in isomerase activity by heat inactivation was not primarily due to oxidation of protein thiol groups in the GSTs. The specific activity of GSTs was approx. 23- and 340-fold those of GSH and apoferritin respectively when comparisons were made on the basis of free thiol concentrations, indicating that free thiol in GSTs cannot account for the majority of observed isomerase activities and suggesting that specific conformations of GSTs are important for such activities. Complete inhibition of the reaction by low concentrations of N-ethylmaleimide (10 microM) demonstrated that intact protein thiols are required for the isomerase activities of GSTs. PMID:9581548

Glutathione S-transferases act as isomerases in isomerization of 13-cis-retinoic acid to all-trans-retinoic acid in vitro.

PubMed

Chen, H; Juchau, M R

1997-11-01

A discovery that rapid enzymic isomerization of 13-cis-retinoic acid (13-cRA) to all-trans-retinoic acid (t-RA) can be catalysed by purified hepatic glutathione S-transferases (GSTs; EC 2.5.1.18) from rat is now reported. Rates of cis-trans isomerization were determined quantitatively by HPLC. GST-catalysed reactions reached equilibrium rapidly, in marked contrast with uncatalysed or GSH-catalysed isomerizations. The GST-catalysed reaction exhibited substrate saturation kinetics with a Km of approx. 8 microM. The maximal velocity of the reaction and the catalytic efficiency of GSTs were determined. The initial rate of the reaction increased linearly as a function of enzyme concentration. Catalysis by GSTs was independent of the presence of GSH, indicating that GSTs act as GSH-independent isomerases as well as transferases. Incubation with guanidine (7-8 M) or heat-inactivation of GSTs (100 degrees C for 3 min) decreased isomerase activities by approx. 50% and 75% respectively. The same heat treatment did not significantly inhibit isomerization catalysed by GSH and apoferritin, indicating that the observed decrease in isomerase activity by heat inactivation was not primarily due to oxidation of protein thiol groups in the GSTs. The specific activity of GSTs was approx. 23- and 340-fold those of GSH and apoferritin respectively when comparisons were made on the basis of free thiol concentrations, indicating that free thiol in GSTs cannot account for the majority of observed isomerase activities and suggesting that specific conformations of GSTs are important for such activities. Complete inhibition of the reaction by low concentrations of N-ethylmaleimide (10 microM) demonstrated that intact protein thiols are required for the isomerase activities of GSTs.

Developmental stage-associated differences in the transplacental distribution of 13-cis- and all-trans-retinoic acid as well as their glucuronides in rats and mice.

PubMed

Tzimas, G; Collins, M D; Nau, H

1995-07-01

In mice and rats, 13-cis-retinoic acid (13-cis-RA) has a much lower teratogenic potency than all-trans-retinoic acid (all-trans-RA). Previous studies on Gestational Day (GD) 11 or 12 (in mice or rats, respectively) showed a limited transfer of 13-cis-RA to the embryo, in contrast to the efficient transplacental passage of all-trans-RA. In the present study we examined if the distribution between maternal circulation and embryo of 13-cis- and all-trans-RA as well as their metabolites is different at gestational times when the placenta is developing from a choriovitelline to a chorioallantoic type. In the first experiment, 13-cis-RA was administered orally to pregnant rats (75 mg/kg/day) daily, from either GD 7 to 12 or 11 to 16. In the second experiment, 13-cis-RA or all-trans-RA was given orally to pregnant mice once on either GD 11 or 14, at two dose levels (10 and 100 mg/kg). HPLC analysis of plasma and embryo samples collected at various time points post-treatment showed that 13-cis-RA was predominantly metabolized to its beta-glucuronide (13-cis-RAG) while all-trans-RA was primarily biotransformed to all-trans-4-oxo-RA and to a lesser extent to all-trans-RAG. 13-cis-RA showed a more efficient transplacental passage to the rat embryo on GD 16 than on GD 12, as indicated by higher ratios of embryonic to maternal plasma concentrations (E/M concentration ratio) on GD 16 vs. GD 12 and its E/M ratio of area-under-the-concentration-time-curve values (E/M AUC ratio; twofold higher on GD 16 vs. GD 12). In the mouse, the E/M concentration ratio of 13-cis-RA was significantly higher on GD 14 than on GD 11 only at the low dose. On the other hand, all-trans-RA and all-trans-4-oxo-RA showed an efficient transfer to the mouse embryo at both gestational times. In both species, 13-cis- and all-trans-RAG embryonic concentrations on the later gestational days exceeded significantly the corresponding ones on the earlier gestational days which resulted in far higher E/M concentration and AUC ratios for each of these metabolites on the later vs earlier gestational days. This may result from a more efficient placental transfer of the RAGs during later gestational stages and/or higher capacity of the late embryo or other conceptal tissues to biotransform RAs in situ to their glucuronides.(ABSTRACT TRUNCATED AT 400 WORDS)

Topical isotretinoin vs. topical retinoic acid in the treatment of acne vulgaris.

PubMed

Domínguez, J; Hojyo, M T; Celayo, J L; Domínguez-Soto, L; Teixeira, F

1998-01-01

This is a clinical, prospective, and longitudinal study comparing the efficacy and incidence of averse effects of topical isotretinoin against those of topical retinoic acid in the treatment of acne vulgaris. The 30 participants were recruited from the patients attending the outpatient clinic of the Department of Dermatology of "Dr Manuel Gea González" General Hospital in Mexico City. They belonged to either sex and any race, their ages ranged between 13 and 30 years, and they presented with 15 to 100 facial inflammatory lesions (papulo-pustules) and/or 15 to 100 noninflammatory lesions (comedones) and no more than three nodulo-cystic lesions. The criteria of exclusion were as follows: pregnancy or lactation, systemic treatment with steroids, antibiotics, antiandrogens, or oral retinoids in the preceding 24 months, treatment with ultraviolet radiation, hypersensitivity to retinoids, or a severe systemic illness. From 44 interviewed patients, 14 were excluded. A detailed clinical history was obtained from the remaining individuals, the degree of seborrhea was recorded, and acne lesions were counted. Each patient received either isotretinoin gel 0.05% or retinoic acid cream 0.05%. The patients were instructed to wash their faces in the mornings and evenings with a neutral soap, and to apply the product after the evening cleansing. The patients were examined again after 2, 4, 8, and 12 weeks of treatment and, at each appointment, the number of lesions was recorded and the severity of acne was graded according to the classification of Plewig and Kligman. The seriousness of the adverse effects, such as stinging, pruritus, erythema, xerosis, and desquamation, was evaluated blindly by an investigator who did not know what group the patient belonged to, and graded as 1 = mild, 2 = moderate, and 3 = severe. The efficacy of each drug was determined by the reduction in the number of lesions between weeks 0 and 12 of treatment. An excellent response corresponded to a 76%-100% reduction of the lesions, a good response to a 51%-75% reduction, a fair response to a 26%-50% reduction, and a poor response to a 0%-25% reduction. The results were analyzed statistically using the chi-square test, the exact test of Fisher and the test of Wilcoxon-Mann-Whitney. The changes in the numbers of lesions between weeks 0 and 12 were analyzed separately for each group of treatment, and the level of statistical significance was fixed at 0.05. The analysis was performed with the aid of a Stat program, version 4.0. The patients were assigned randomly to either Group I (isotretinoin) or Group II (retinoic acid). Each group was composed of 15 individuals and, as a coincidence, in each group there were nine women and six men. The clinical differences between the groups at the first visit were not statistically significant. In both groups, there was, in general, a good response to treatment (Fig. 1). Both drugs had a similar degree of efficacy on inflammatory lesions. At the first visit, grades III and IV predominated, whereas, after 12 weeks of treatment, most patients were classified in grades I or II (Fig. 2). Similar results were observed regarding noninflammatory lesions (Fig. 3). Ten of the patients of Group II complained of stinging associated with the treatment, especially at weeks 8 and 12, as well as erythema and desquamation at the 12th week. Erythema and stinging lasted for minutes or hours, whereas desquamation persisted for several days. Seven individuals receiving isotretinoin mentioned irritation, which was of a mild degree.

Effect of 2-(4-aminophenylmethyl)-6-hydroxy-3, 4-dihydronaphthalen-1(2H)-one on all-trans and 13-cis-retinoic acid levels in plasma quantified by high perfomance liquid chromatography coupled to tandem mass spectrometry.

PubMed

Angotti, Marc; Hartmann, Rolf W; Kirby, Andrew J; Simons, Claire; Nicholls, Paul J; Sewell, Robert D E; Smith, H John

2005-06-01

The effect of the titled tetralone as a retinoic acid metabolism blocking agent (RAMBA) in vivo in comparison with ketoconazole, a well known cytochrome P450 inhibitor, was studied. Development of a HPLC/MS/MS method for the quantification of retinoic acid levels extracted from rat plasma was used to demonstrate that ketoconazole and the tetralone (100 mg/kg) enhanced the endogenous plasma concentration of retinoic acid. Levels of retinoid were raised from a control value of 0.11 to 0.15 and 0.17 ng/mL after treatment with tetralone and ketoconazole respectively showing that the tetralone and ketoconazole lead to comparable effects, indicating an inhibitory activity of the tetralone on retinoic acid metabolism.

Micro liquid chromatography-mass spectrometry with direct liquid introduction used for separation and quantitation of all-trans- and 13-cis-retinoic acids and their 4-oxo metabolites in human plasma.

PubMed

Ranalder, U B; Lausecker, B B; Huselton, C

1993-07-23

The separation and quantitation of the pentafluorobenzyl derivatives of all-trans- and 13-cis-retinoic acids and their 4-oxo metabolites in human plasma on micro high-performance liquid chromatographic columns (0.32 mm I.D.) is described. The column outlet was directly coupled to the source of a quadrupole mass spectrometer via a simple SFC-frit interface. Negative ion chemical ionization conditions were obtained by coaxial introduction of ammonia as a reagent gas. A signal-to-noise ratio well above 3 was obtained for 1 pg of each analyte injected. The limit of quantitation calculated from spiked biological plasma extracts was 0.3 ng/ml.

BMY 30047: A novel topically active retinoid with low local and systemic toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nair, X.; Quigley, J.; Tramposch, K.M.

In the treatment of various dermatological disorders, topically applied retinoids have potential therapeutic use with the advantage of improved localized activity and lower toxicity over systemically administered retinoids. However, most retinoids cause a significant degree of local irritation. In the present study, the ability to produce local activity with low local irritation potential was evaluated with a novel retinoic acid derivative. BMY 30047 (11-cis, 13-cis-12-hydroxymethylretinoic acid delta-lactone) is one of a series of retinoic acid derivatives in which the carboxyl function of the polar end was modified with the aim of achieving reduced local irritation and systemic toxicity while retainingmore » the local therapeutic effect. BMY 30047 was evaluated and compared with all-trans retinoic acid for topical retinoid activity in several preclinical assay systems, including the utricle reduction assay in rhino mice, 12-o-tetradecanoylphorbol 13-acetate ester-stimulated ornithine decarboxylase induction in hairless mice and the UV light-induced photodamaged skin model in hairless mice. BMY 30047 was assessed for retinoid-type side effects by evaluating the skin irritation potential in rabbits after repeated topical application, and hypervitaminosis A-inducing potential in mice after i.p. injection. BMY 30047 demonstrated significant topical retinoid activity in several in vivo models with less skin irritation potential relative to the most used clinical concentrations of all-trans retinoic acid. BMY 30047 also showed very little systemic activity and did not produce any evidence of hypervitaminosis A syndrome at systemic doses 20 times greater than the no-effect dose of all-trans retinoic acid.« less

Evidence for percutaneous absorption of isotretinoin from the photo-isomerization of topical tretinoin.

PubMed

Lehman, P A; Malany, A M

1989-11-01

Tretinoin (0.1% Retin-A cream) was topically applied to human cadaver skin in vitro using Franz diffusion chambers. The photo-isomerization of tretinoin and retinoic acid percutaneous absorption in the absence of metabolic activity were assessed with and without ambient light exposure to the skin. Using HPLC, UV, and GC/MSD, a retinoid exhibiting identical chromatographic and spectral characteristics of isotretinoin was observed in the samples from the skin exposed to light, but was virtually absent in the skin samples maintained in the dark. From a single topical application of tretinoin, isotretinoin was as abundant as tretinoin in the chamber receiver solution, dermis, epidermis, and on the skin surface at 24 h after topical application. The data suggest the possibility that isotretinoin may have an important role in the pharmacology of topically applied tretinoin.

The retinoids. A review of their clinical pharmacology and therapeutic use.

PubMed

Orfanos, C E; Ehlert, R; Gollnick, H

1987-10-01

With the introduction of the synthetic retinoids, oral therapy with an acceptable risk/benefit ratio became possible for a variety of skin diseases including severe acne, psoriasis and numerous genodermatoses. This article reviews the clinical pharmacology, mechanisms of action and therapeutic use of the retinoids, particularly isotretinoin (13-cis-retinoic acid) and etretinate. The free aromatic acid of etretinate, etretin, and the new polyaromatic retinoid compounds (arotinoids) are also discussed. Isotretinoin is used clinically for oral therapy of severe acne, but is also recommended for severe Gram-negative folliculitis and rosacea not responding to traditional therapy. The results of several studies have established that acne therapy should be started with 1.0 mg/kg/day for 2 to 3 months after which the daily dosage should be lowered to 0.2 to 0.5 mg/kg/day for another 2 to 3 months. This therapeutic regimen of isotretinoin has proven to be the most successful in preventing relapses. Etretinate is particularly useful for oral therapy of widespread plaque-like, pustular and erythrodermic psoriasis, and of generalised lichen planus, Darier's disease and severe congenital ichthyoses. Whereas pustular forms of psoriasis require a high daily dosage of 1.0 mg/kg/day, erythrodermic psoriasis should be treated with a lower dosage of 0.25 to 0.35 mg/kg/day. In chronic plaque-like psoriasis, a mean daily dosage of 0.5 mg/kg/day over several weeks to months, usually combined with photo(chemo)therapy, tar or dithranol, is recommended. Other indications for oral etretinate therapy are adequately treated with a moderate dosage of 0.4 to 0.75 mg/kg/day. Etretin differs from etretinate in having a much shorter elimination half-life of 2 to 3 days, in contrast to 80 to 100 days after long term administration of etretinate. Moreover, it has not been shown to increase serum cholesterol levels. However, its clinical efficacy is not yet clearly established. Among the arotinoids, arotinoid ethylester (Ro 13-6298) has revealed the best anti-psoriatic and anti-inflammatory effects at extremely low dose levels. Furthermore, no significant elevations of serum lipids have been observed. Taking its prolonged elimination half-life and its efficacy/side effect ratio into account, the drug is comparable to etretinate. The free arotinoid carboxylic acid (Ro 13-7410) is currently undergoing clinical investigation. Another arotinoid, the parent compound Ro 15-0778, has not demonstrated any convincing clinical efficacy in acne or psoriasis, but topical anti-inflammatory effects were evident in some models.(ABSTRACT TRUNCATED AT 400 WORDS)

Schools of pharmacology: retinoid update.

PubMed

Scheinfeld, Noah

2006-10-01

The most widely used retinoids include topical tretinoin (Retin-A), adapalene (Differin), topical tazarotene (Tazorac), isotretinoin (Accutane), and acitretin (Soriatane). This article will review new uses and developments in tazarotene (its failure to secure FDA approval in oral form for psoriasis), adapalene (its new 0.3% gel form and use in rosacea), alitretinoin (its use in photoaging), bexarotene (its use for psoriasis and chronic hand dermatitis), isotretinoin (the IPledge program, its use for neuroblastoma and branded formulation pharmacological superiority to generics), and retinoic acid metabolism-blocking agents (RAMBAs) (liarazole use for ichthyosis and psoriasis).

Quantitative high-throughput determination of endogenous retinoids in human plasma using triple-stage liquid chromatography/tandem mass spectrometry.

PubMed

Gundersen, Thomas E; Bastani, Nasser E; Blomhoff, Rune

2007-01-01

A high-throughput ultrasensitive analytical method based on liquid chromatography with positive ion atmospheric pressure chemical ionization (APCI) coupled to tandem mass spectrometric detection (LC/MS/MS) was developed for the determination of all-trans-4-oxo-retinoic acid (at4oxoRA), 13-cis-4-oxo-retinoic acid (13c4oxoRA), 13-cis-retinoic acid (13cRA), all-trans-retinoic acid (atRA) and all-trans-retinol (atROH) in human plasma. A stable isotope of atRA was used as internal standard (IS). The analytes and IS were isolated from 100 microL plasma by acetonitrile mono-phase extraction (MPE) performed in black 96-well microtiterplates. A 100 microL injection was focused on-column and chromatographed on an Agilent ZORBAX SB-C18 rapid-resolution high-throughput (RRHT) column with 1.8-microm particles (4.6 mmx50 mm) maintained at 60 degrees C. The initial mobile phase composition was acetonitrile/water/formic acid (10:90:0.1, v/v/v) delivered at 1.8 mL/min. Elution was accomplished by a fast gradient to acetonitrile/methanol/formic acid (90:10:0.1, v/v/v). The method had a chromatographic total run time of 7 min. An Applied Biosystems 4000 Q TRAP linear tandem mass spectrometer equipped with a heated nebulizer (APCI) ionization source was operated in multiple reaction monitoring (MRM) mode with the precursor-to-product ion transitions m/z 315.4-->297 (4-oxo-retinoic acids), 301.2-->205 (retinoic acids), 305.0-->209 (IS) and 269.2-->93 (retinol) used for quantification. The assay was fully validated and found to have acceptable accuracy, precision, linearity, sensitivity and selectivity. The mean extraction recoveries from spiked plasma samples were 80-105% for the various retinoids at three different levels. The intra-day accuracy of the assay was within 8% of nominal and intra-day precision was better than 8% coefficient of variance (CV) for retinoic acids. Inter-day precision results for quality control samples run over a 12-day period alongside clinical samples showed mean precision better than 12.5% CV. The limit of quantification was in the range of 0.1-0.2 ng/mL and the mass limit of detection (mLOD) was in the range 1-4 pg on column for the retinoic acids. The assay has been successfully applied to the analysis of 1700 plasma samples. Copyright (c) 2007 John Wiley & Sons, Ltd.

RIP140/PGC-1α axis involved in vitamin A-induced neural differentiation by increasing mitochondrial function.

PubMed

Mu, Qing; Yu, Weidong; Zheng, Shuying; Shi, Hongxia; Li, Mei; Sun, Jie; Wang, Di; Hou, Xiaoli; Liu, Ling; Wang, Xinjuan; Zhao, Zhuran; Liang, Rong; Zhang, Xue; Dong, Wei; Zeng, Chaomei; Guo, Jingzhu

2018-03-07

Vitamin A deficiency and mitochondrial dysfunction are both associated with neural differentiation-related disorders, such as Alzheimer's disease (AD) and Down syndrome (DS). The mechanism of vitamin A-induced neural differentiation and the notion that vitamin A can regulate the morphology and function of mitochondria in its induction of neural differentiation through the RIP140/PGC-1α axis are unclear. The aim of this study was to investigate the roles and underlying mechanisms of RIP140/PGC-1α axis in vitamin A-induced neural differentiation. Human neuroblastoma cells (SH-SY5Y) were used as a model of neural stem cells, which were incubated with DMSO, 9-cis-retinoic acid (9-cis-RA), 13-cis-retinoic acid (13-cis-RA) and all-trans-retinoic acid (at-RA). Neural differentiation of SH-SY5Y was evaluated by Sandquist calculation, combined with immunofluorescence and real-time polymerase chain reaction (PCR) of neural markers. Mitochondrial function was estimated by ultrastructure assay using transmission electron microscopy (TEM) combined with the expression of PGC-1α and NEMGs using real-time PCR. The participation of the RA signaling pathway was demonstrated by adding RA receptor antagonists. Vitamin A derivatives are able to regulate mitochondrial morphology and function, and furthermore to induce neural differentiation through the RA signaling pathway. The RIP140/PGC-1α axis is involved in the regulation of mitochondrial function in vitamin A derivative-induced neural differentiation.

Effects of isotretinoin on the olfactory function in patients with acne.

PubMed

Kartal, Demet; Yaşar, Mehmet; Kartal, Levent; Özcan, Ibrahim; Borlu, Murat

2017-01-01

Isotretinoin is a synthetic analog of vitamin A. Recent studies support a role for retinoic acid in the recovery of olfactory function following injury in mice. This study aimed at determining the effect of isotretinoin on olfactory function in patients who have acne and are otherwise healthy. Forty-five patients (aged 25-40 years) with acne were included in the study. All patients underwent a rhinological examination. Olfactory function was assessed by the Sniffin' Sticks Test. The test was assessed at baseline and in the third month of isotretinoin treatment. Isotretinoin improved the performance of patients in the olfactory test. The SST score increased from 8.7±1.09 to 9.5±1.19 (p<0.001), prevalence of hyposmia decreased from 40% to 24% and normosmia increased from 60% to 75% (p=0.059). The percentage of patients whose olfactory function was categorized as "good" increased from 6% to 21.3%. This increase was statistically significant (p<0.05). Absence of a control group is one of the limitations of this study. Also, we did not evaluate patients with smell test after stopping isotretinoin treatment. We examined the effect of systemic isotretinoin on olfactory function. It can be concluded from the present investigation that isotretinoin therapy improves the sense of smell.

Human skin levels of retinoic acid and cytochrome P-450-derived 4-hydroxyretinoic acid after topical application of retinoic acid in vivo compared to concentrations required to stimulate retinoic acid receptor-mediated transcription in vitro.

PubMed Central

Duell, E A; Aström, A; Griffiths, C E; Chambon, P; Voorhees, J J

1992-01-01

Metabolism of retinoic acid to a less active metabolite, 4-hydroxyretinoic acid, occurs via cytochrome P-450 isozyme(s). Effect of a pharmacological dose of retinoic acid on the level of retinoic acid in skin and on cytochrome P-450 activity was investigated. A cream containing 0.1% retinoic acid or cream alone was applied topically to adult human skin for four days under occlusion. Treated areas were removed by a keratome and a microsomal fraction was isolated from each biopsy. In vitro incubation of 3H-retinoic acid with microsomes from in vivo retinoic acid treated sites resulted in a 4.5-fold increase (P = 0.0001, n = 13) in its transformation to 4-hydroxyretinoic acid in comparison to in vitro incubations with microsomes from in vivo cream alone treated sites. This cytochrome P-450 mediated activity was oxygen- and NADPH-dependent and was inhibited 68% by 5 microM ketoconazole (P = 0.0035, n = 8) and 51% by carbon monoxide (P = 0.02, n = 6). Cotransfection of individual retinoic acid receptors (RARs) or retinoid X receptor-alpha (RXR-alpha) and a chloramphenicol acetyl transferase (CAT) reporter plasmid containing a retinoic acid responsive element into CV-1 cells was used to determine the ED50 values for stimulation of CAT activity by retinoic acid and its metabolites. Levels of all trans and 13-cis RA in RA-treated tissues were greater than the ED50 values determined for all three RARs with these compounds. Furthermore, the level of all trans RA was greater than the ED50 for RXR-alpha whereas the 4-OH RA level was greater than the ED50 for RAR-beta and RAR-gamma but less than for RAR-alpha and RXR-alpha. These data suggest that there are sufficient amounts of retinoic acid in treated skin to activate gene transcription over both RARs and RXR-alpha. PMID:1328295

A randomized phase II chemoprevention trial of 13-CIS retinoic acid with or without alpha tocopherol or observation in subjects at high risk for lung cancer.

PubMed

Kelly, Karen; Kittelson, John; Franklin, Wilbur A; Kennedy, Timothy C; Klein, Catherine E; Keith, Robert L; Dempsey, Edward C; Lewis, Marina; Jackson, Mary K; Hirsch, Fred R; Bunn, Paul A; Miller, York E

2009-05-01

No chemoprevention strategies have been proven effective for lung cancer. We evaluated the effect of 13-cis retinoic acid (13-cis RA), with or without alpha tocopherol, as a lung cancer chemoprevention agent in a phase II randomized controlled clinical trial of adult subjects at high risk for lung cancer as defined by the presence of sputum atypia, history of smoking, and airflow obstruction, or a prior surgically cured nonsmall cell lung cancer (disease free, >3 years). Subjects were randomly assigned to receive either 13-cis RA, 13-cis RA plus alpha tocopherol (13-cis RA/alpha toco) or observation for 12 months. Outcome measures are derived from histologic evaluation of bronchial biopsy specimens obtained by bronchoscopy at baseline and follow-up. The primary outcome measure is treatment "failure" defined as histologic progression (any increase in the maximum histologic score) or failure to return for follow-up bronchoscopy. Seventy-five subjects were randomized (27/22/26 to observations/13-cis RA/13-cis RA/alpha toco); 59 completed the trial; 55 had both baseline and follow-up bronchoscopy. The risk of treatment failure was 55.6% (15 of 27) and 50% (24 of 48) in the observation and combined (13 cis RA plus 13 cis RA/alpha toco) treatment arms, respectively (odds ratio adjusted for baseline histology, 0.97; 95% confidence interval, 0.36-2.66; P = 0.95). Among subjects with complete histology data, maximum histology score in the observation arm increased by 0.37 units and by 0.03 units in the treated arms (difference adjusted for baseline, -0.18; 95% confidence interval, -1.16 to 0.81; P = 0.72). Similar (nonsignificant) results were observed for treatment effects on endobronchial proliferation as assessed by Ki-67 immunolabeling. Twelve-month treatment with 13-cis RA produced nonsignificant changes in bronchial histology, consistent with results in other trials. Agents advancing to phase III randomized trials should produce greater histologic changes. The addition of alpha tocopherol did not affect toxicity.

A Randomized Phase II Chemoprevention Trial of 13-CIS Retinoic Acid with Or without α Tocopherol or Observation in Subjects at High Risk for Lung Cancer

PubMed Central

Kelly, Karen; Kittelson, John; Franklin, Wilbur A.; Kennedy, Timothy C.; Klein, Catherine E.; Keith, Robert L.; Dempsey, Edward C.; Lewis, Marina; Jackson, Mary K.; Hirsch, Fred R.; Bunn, Paul A.; Miller, York E.

2011-01-01

No chemoprevention strategies have been proven effective for lung cancer. We evaluated the effect of 13-cis retinoic acid (13-cis RA), with or without α tocopherol, as a lung cancer chemoprevention agent in a phase II randomized controlled clinical trial of adult subjects at high risk for lung cancer as defined by the presence of sputum atypia, history of smoking, and airflow obstruction, or a prior surgically cured nonsmall cell lung cancer (disease free, >3 years). Subjects were randomly assigned to receive either 13-cis RA, 13-cis RA plus α tocopherol (13-cis RA/α toco) or observation for 12 months. Outcome measures are derived from histologic evaluation of bronchial biopsy specimens obtained by bronchoscopy at baseline and follow-up. The primary outcome measure is treatment “failure” defined as histologic progression (any increase in the maximum histologic score) or failure to return for follow-up bronchoscopy. Seventy-five subjects were randomized (27/22/26 to obervations/13-cis RA/13-cis RA/α toco); 59 completed the trial; 55 had both baseline and follow-up bronchoscopy. The risk of treatment failure was 55.6% (15 of 27) and 50% (24 of 48) in the observation and combined (13 cis RA plus 13 cis RA/α toco) treatment arms, respectively (odds ratio adjusted for baseline histology, 0.97; 95% confidence interval, 0.36–2.66; P = 0.95). Among subjects with complete histology data, maximum histology score in the observation arm increased by 0.37 units and by 0.03 units in the treated arms (difference adjusted for baseline, −0.18; 95% confidence interval, −1.16 to 0.81; P = 0.72). Similar (nonsignificant) results were observed for treatment effects on endobronchial proliferation as assessed by Ki-67 immunolabeling. Twelve-month treatment with 13-cis RA produced nonsignificant changes in bronchial histology, consistent with results in other trials. Agents advancing to phase III randomized trials should produce greater histologic changes. The addition of α tocopherol did not affect toxicity. PMID:19401528

Placental transfer and developmental effects of 9-cis retinoic acid in mice.

PubMed

Kochhar, D M; Jiang, H; Penner, J D; Heyman, R A

1995-04-01

9-cis retinoic acid (RA) is a naturally occurring isomer of all-trans RA. While both isomers can bind with high affinity and activate RA receptors, only 9-cis RA is the specific ligand for the retinoid X receptors. 9-cis RA has also been shown to be much more potent than all-trans RA in inducing digit duplication in the chick embryo wing bud. To gain further insight into its mechanisms, here we investigated the teratogenic activity in pregnant mice of 9-cis RA and compared it with those of all-trans RA and 13-cis RA. Using frequency and severity of limb reduction defects as well as palatal clefts in the resultant fetuses as indicators, we found that orally administered 9-cis RA was one-half as potent a teratogen as all-trans RA. That 9-cis RA was intrinsically less active than all-trans RA was deduced by comparing the inhibitory activities of the two retinoids in the limb bud mesenchymal cell micromass cultures using chondrogenesis as an end-point. Since placental transfer of cis isomers of RA is generally poor, we monitored the identities and amounts of retinoids in the embryo after administration of 9-cis RA to the mother. We found that 9-cis RA undergoes extensive metabolism and isomerization during absorption resulting in a number of metabolites in the maternal circulation within 30 min after administration. Although some of these metabolites remain to be identified, the most abundant RA isomers in the plasma coeluted with 13-cis RA.(ABSTRACT TRUNCATED AT 250 WORDS)

Retinoic acid concentrations in patients with squamous cell carcinoma of the head and neck.

PubMed

Wahlberg, P; Fex, G

1996-02-01

The serum concentrations of all-trans (atRA) and 13-cis (13cRA) retinoic acid were determined by high performance liquid chromatography in 27 patients with squamous cell carcinoma of the head and neck and in 80 healthy controls. This investigation seemed relevant as ethanol is an aetiological factor in these cancers and has been suggested to interfere with the synthesis of atRA. Neither the serum concentration of atRA nor that of 13cRA differed between patients and controls. The serum atRA concentration did not differ between fasting and non-fasting patients, but the serum 13cRA concentration was significantly higher in non-fasting than in fasting patients, probably due to the dietary retinoid content.

Low plasma levels of cholecalciferol and 13-cis-retinoic acid in tuberculosis: implications in host-based chemotherapy.

PubMed

Srinivasan, Anand; Syal, Kirtimaan; Banerjee, Dibyajyoti; Hota, Debasish; Gupta, Dheeraj; Kaul, Deepak; Chakrabarti, Amitava

2013-10-01

The aim of this study was to estimate the concentration of cholecalciferol and 13-cis-retinoic acid (RA) in the plasma and pleural fluid of patients with tuberculosis (TB) against controls. Plasma levels of cholecalciferol and 13-cis-RA were measured in 22 patients with TB and healthy controls and their pleural fluids levels were measured in 6 TB patients and diseased controls by established high-performance liquid chromatography-based procedure. Cholecalciferol levels in plasma and pleural fluid of patients with TB and healthy controls were 67.45 (10.71) nmol/L and 21.40 (8.58) nmol/L compared with 117.43 (18.40) nmol/L (P < 0.001) and 94.73 (33.34) nmol/L (P = 0.0049), respectively. 13-cis-RA level in the plasma of patients with TB and healthy controls were 1.51 (0.72) nmol/L and 6.67 (0.81) nmol/L (P < 0.001), respectively. 13-cis-RA was not detectable in pleural fluid. The levels of both the agents were lower in patients with TB than in controls. It was observed that in patients with TB there is a combined deficiency of cholecalciferol and 13-cis-RA compared with healthy volunteers. Because cholecalciferol and 13-cis-RA are in equilibrium with active ingredients of vitamins A and D, we feel that there is a combined deficiency of these vitamins in patients with TB. There is an evidence that concomitant vitamin A and D supplementation can kill intracellular Mycobacterium tuberculosis in vitro. Therefore, the observations made in this study can pave the path for a trial of combined supplementation of available formulations of vitamin A and D (cholecalciferol and 13-cis-RA) for novel anti-tubercular drug therapy. Because such an approach is host-based it has potential to treat even multidrug-resistant and extensively drug-resistant forms of TB. Copyright © 2013 Elsevier Inc. All rights reserved.

Systemic isotretinoin therapy normalizes exaggerated TLR-2-mediated innate immune responses in acne patients

PubMed Central

Dispenza, Melanie C.; Wolpert, Ellen B.; Gilliland, Kathryn L.; Dai, Pingqi; Cong, Zhaoyuan; Nelson, Amanda M.; Thiboutot, Diane M.

2012-01-01

Retinoids are used in the treatment of inflammatory skin diseases and malignancies, but studies characterizing the in vivo actions of these drugs in humans are lacking. Isotretinoin is a pro-drug for all-trans retinoic acid that can induce long-term remissions of acne; however, its complete mechanism of action is unknown. We hypothesized that isotretinoin induces remission of acne by normalizing the innate immune response to the commensal bacterium P. acnes. Compared to normal subjects, peripheral blood monocytes from acne patients expressed significantly higher levels of TLR-2 and exhibited significantly greater induction of TLR-2 expression following P. acnes stimulation. Treatment of patients with isotretinoin significantly decreased monocyte TLR-2 expression and subsequent inflammatory cytokine response to P. acnes by one week of therapy. This effect was sustained six months following cessation of therapy, indicating that TLR-2 modulation may be involved in the durable therapeutic response to isotretinoin. This study demonstrates that isotretinoin exerts immunomodulatory effects in patients and sheds light on a potential mechanism for its long-term effects in acne. The modulation of TLR-2 expression on monocytes has important implications in other inflammatory disorders characterized by TLR-2 dysregulation. PMID:22513780

Outcome of High-Risk Stage 3 Neuroblastoma with Myeloablative Therapy and 13-cis-Retinoic Acid: A Report from the Children’s Oncology Group

PubMed Central

Park, Julie R.; Villablanca, Judith G.; London, Wendy B.; Gerbing, Robert B.; Haas-Kogan, Daphne; Stanton Adkins, E.; Attiyeh, Edward F.; Maris, John M.; Seeger, Robert C.; Patrick Reynolds, C.; Matthay, Katherine K.

2009-01-01

Background The components of therapy required for patients with INSS Stage 3 neuroblastoma and high risk features remain controversial. Procedure A retrospective cohort design was used to determine if intensive chemoradiotherapy with purged autologous bone marrow rescue (ABMT) and/or 13-cis-retinoic acid (13-cis-RA) improved outcome for patients with high-risk neuroblastoma that was not metastatic to distant sites. We identified 72 patients with INSS Stage 3 neuroblastoma enrolled between 1991 and 1996 on the Phase III CCG 3891 randomized trial. Patients were analyzed on an intent-to-treat basis using a log-rank test. Results The 5-year event-free survival (EFS) and overall survival (OS) rates for patients with Stage 3 neuroblastoma were 55 +/- 6% and 59% +/- 6%, respectively (n=72). Patients randomized to ABMT (n=20) had 5-year EFS of 65% +/- 11% and OS of 65% +/- 11% compared to 41% +/- 11 (p=0.21) and 46% +/- 11% (p=0.23) for patients randomized to CC (n=23), respectively. Patients randomized to 13-cis-RA (n=23) had 5-year EFS of 70% +/- 10% and OS of 78% +/- 9% compared to 63% +/- 12% (p=0.67) and 67% +/- 12% (p=0.55) for those receiving no further therapy (n=16), respectively. Patients randomized to both ABMT and 13-cis-RA (n=6) had a 5-year EFS of 80% ± 11% and OS of 100%. Conclusion Patients with high-risk Stage 3 neuroblastoma have an overall poor prognosis despite aggressive chemoradiotherapy. Further studies are warranted to determine if myeloablative consolidation followed by 13-cis-RA maintenance therapy statistically significantly improves outcome. PMID:18937318

Outcome of high-risk stage 3 neuroblastoma with myeloablative therapy and 13-cis-retinoic acid: a report from the Children's Oncology Group.

PubMed

Park, Julie R; Villablanca, Judith G; London, Wendy B; Gerbing, Robert B; Haas-Kogan, Daphne; Adkins, E Stanton; Attiyeh, Edward F; Maris, John M; Seeger, Robert C; Reynolds, C Patrick; Matthay, Katherine K

2009-01-01

The components of therapy required for patients with INSS Stage 3 neuroblastoma and high-risk features remain controversial. A retrospective cohort design was used to determine if intensive chemoradiotherapy with purged autologous bone marrow rescue (ABMT) and/or 13-cis-retinoic acid (13-cis-RA) improved outcome for patients with high-risk neuroblastoma that was not metastatic to distant sites. We identified 72 patients with INSS Stage 3 neuroblastoma enrolled between 1991 and 1996 on the Phase 3 CCG-3891 randomized trial. Patients were analyzed on an intent-to-treat basis using a log-rank test. The 5-year event-free survival (EFS) and overall survival (OS) rates for patients with Stage 3 neuroblastoma were 55 +/- 6% and 59 +/- 6%, respectively (n = 72). Patients randomized to ABMT (n = 20) had 5-year EFS of 65 +/- 11% and OS of 65 +/- 11% compared to 41 +/- 11 (P = 0.21) and 46 +/- 11% (P = 0.23) for patients randomized to CC (n = 23), respectively. Patients randomized to 13-cis-RA (n = 23) had 5-year EFS of 70 +/- 10% and OS of 78 +/- 9% compared to 63 +/- 12% (P = 0.67) and 67 +/- 12% (P = 0.55) for those receiving no further therapy (n = 16), respectively. Patients randomized to both ABMT and 13-cis-RA (n = 6) had a 5-year EFS of 80 +/- 11% and OS of 100%. Patients with high-risk Stage 3 neuroblastoma have an overall poor prognosis despite aggressive chemoradiotherapy. Further studies are warranted to determine if myeloablative consolidation followed by 13-cis-RA maintenance therapy statistically significantly improves outcome.

Effects of isotretinoin on the olfactory function in patients with acne*

PubMed Central

Kartal, Demet; Yaşar, Mehmet; Kartal, Levent; Özcan, Ibrahim; Borlu, Murat

2017-01-01

Background Isotretinoin is a synthetic analog of vitamin A. Recent studies support a role for retinoic acid in the recovery of olfactory function following injury in mice. Objective This study aimed at determining the effect of isotretinoin on olfactory function in patients who have acne and are otherwise healthy. Methods Forty-five patients (aged 25-40 years) with acne were included in the study. All patients underwent a rhinological examination. Olfactory function was assessed by the Sniffin' Sticks Test. The test was assessed at baseline and in the third month of isotretinoin treatment. Results Isotretinoin improved the performance of patients in the olfactory test. The SST score increased from 8.7±1.09 to 9.5±1.19 (p<0.001), prevalence of hyposmia decreased from 40% to 24% and normosmia increased from 60% to 75% (p=0.059). The percentage of patients whose olfactory function was categorized as "good" increased from 6% to 21.3%. This increase was statistically significant (p<0.05). Study limitations Absence of a control group is one of the limitations of this study. Also, we did not evaluate patients with smell test after stopping isotretinoin treatment. Conclusion We examined the effect of systemic isotretinoin on olfactory function. It can be concluded from the present investigation that isotretinoin therapy improves the sense of smell. PMID:28538877

Topical adapalene gel 0.1% vs. isotretinoin gel 0.05% in the treatment of acne vulgaris: a randomized open-label clinical trial.

PubMed

Ioannides, D; Rigopoulos, D; Katsambas, A

2002-09-01

Topical application of isotretinoin and adapalene has proved effective in treating acne vulgaris. Both drugs demonstrate therapeutic advantages and less irritancy over tretinoin, the most widely used treatment for acne. They both act as retinoid agonists, but differ in their affinity profile for nuclear and cytosolic retinoic acid receptors. To compare the efficacy and tolerability of adapalene gel 0.1% and isotretinoin gel 0.05% in the treatment of acne vulgaris of the face, in a randomized open-label clinical trial. Eighty patients were enrolled and were instructed to apply adapalene gel 0.1% or isotretinoin gel 0.05% once daily over a 12-week treatment period. Efficacy determination included noninflammatory and inflammatory lesion counts by the investigator and global evaluation of improvement. Cutaneous tolerance was assessed by determining erythema, scaling and burning with pruritus. Adapalene and isotretinoin gels were highly effective in treating facial acne. Adapalene gel produced greater reductions in noninflammatory and inflammatory lesion counts than did isotretinoin gel, but differences between treatments were not statistically significant. Adapalene gel was significantly better tolerated than isotretinoin gel during the whole treatment period. The two gels studied demonstrated comparable efficacy. When adapalene and isotretinoin were compared, significantly lower skin irritation was noted with adapalene, indicating that adapalene may begin a new era of treatment with low-irritant retinoids.

Prostaglandin H synthase-catalyzed oxidation of all-trans- and 13-cis-retinoic acid to carbon-centered and peroxyl radical intermediates.

PubMed

Freyaldenhoven, M A; Lloyd, R V; Samokyszyn, V M

1996-06-01

Due to the importance of all-trans-retinoic acid (RA) in the treatment of various dermatological conditions and the wide distribution of prostaglandin H synthase (PGHS) in tissues, we have further examined the mechanisms involved in the hydroperoxide-dependent cooxidation of RA and its isomer, 13-cis-retinoic acid ((13Z)-RA), by PGHS. Hydroperoxide-dependent, PGHS-catalyzed oxidation of RA and (13Z)-RA was shown to form free radical adducts, using electron spin resonance (ESR) spin trapping techniques and 5-phenyl-4-penten-1-yl hydroperoxide (PPHP) or 13-hydroperoxy-9-cis-11-trans-octadecadienoic acid (13-OOH-18:2) as hydroperoxide substrates. Utilization of the spin trap alpha-phenyl-N-tert-butylnitrone (PBN) resulted in the detection of (13Z)-RA-PBN and RA-PBN adducts whose spectra were characterized by hyperfine coupling constants of aH = 4.16/aN = 15.69 and aH = 3.01/aN =15.92, respectively. Identical experiments under anaerobic conditions were carried out using the spin trap 2-methyl-2-nitrosopropane (NtB) which yielded nitroxide adducts whose spectra were characterized by a triplet of doublets with values of aH = 3.49/aN = 15.84 for the (13Z)-RA adduct and aH = 3.49/aN = 15.88 for the RA adduct. These results are indicative of secondary carbon-centered radical formation. We also used (+)-benzo[a]pyrene 7(S),8(S)-dihydrodiol ((+)-BP-7,8-diol) as a peroxyl radical probe. The results demonstrated the formation of (+)-BP-7,8-diol-derived tetrols, with the trans-anti tetrol representing the major oxidation product in systems undergoing PPHP-dependent, PGHS-catalyzed oxidation of (13Z)-RA or RA. These results are consistent with the formation of peroxyl radicals in these systems. In all experiments, the (13Z)-RA isomer appeared to be a better substrate for the enzyme compared to the all-trans isomer. Collectively these results provide further evidence to support the previously proposed mechanism for retinoid oxidation by PGHS involving the intermediacy of C4 carbon-centered radicals which subsequently react with dioxygen, yielding retinoid-derived peroxyl radicals.

9-cis-retinoic acid increases apolipoprotein AI secretion and mRNA expression in HepG2 cells.

PubMed

Haghpassand, M; Moberly, J B

1995-10-01

HepG2 cells were studied as a model for regulation of hepatic apolipoprotein AI (apo AI) secretion and gene expression by 9-cis-retinoic acid. HepG2 cells cultured on plastic dishes were exposed to 9-cis-retinoic acid (9-cis-RA) for 48 h with a complete media change at 24 h. Apo AI mass in cultured media was determined by ELISA, by quantitative immunoblotting and by steady-state 35S-methionine labeling. Messenger RNA levels were determined by RNase protection using probes for apo AI and the housekeeping gene, glyceraldehyde 3-phosphate dehydrogenase (G3PDH). 9-cis-RA increased secretion of apo AI by 52% at doses of 10 and 1 microM (6.3 +/- 0.6 vs. 4.2 +/- 0.3; P < 0.005; 6.1 +/- 0.3 vs. 4.0 +/- 0.7 ng of apo AI/mg cell protein, P < 0.05) and by 35% at 0.1 microM (5.5 +/- 0.6 vs. 4.1 +/- 0.4 ng apo AI/mg protein, P < 0.05, n = 4). Immunoblotting results were consistent with results from ELISA (70% increase at 10 microM 9-cis-RA, P < 0.001; 34% increase at 1 microM, P < 0.005, n = 3). Metabolically labeled apoAI in the medium was increased by 39% following steady-state labeling in the presence of 10 microM 9-cis-RA (597 +/- 7 vs. 430 +/- 13 DPM/microliters media; P < 0.001; n = 4). 9-cis-RA (10 microM) also increased HepG2 cell apo AI mRNA expression by 76% (68 700 +/- 400 vs. 38 900 +/- 2700 DPM, P < 0.01, n = 4), whereas expression of G3PDH mRNA was slightly decreased (14%, P < 0.05). Thus, 9-cis-RA stimulates apo AI expression in HepG2 cells, suggesting a role for retinoids in activating endogenous apo AI gene expression.

Minor malformations characteristic of the retinoic acid embryopathy and other birth outcomes in children of women exposed to topical tretinoin during early pregnancy.

PubMed

Loureiro, Kirsten D; Kao, Kelly K; Jones, Kenneth Lyons; Alvarado, Sonia; Chavez, Carmen; Dick, Lyn; Felix, Robert; Johnson, Diana; Chambers, Christina D

2005-07-15

Topical tretinoin (Retin-A) is used to treat acne and photodamaged skin. Its teratogenic potential is of concern due to its similarity to isotretinoin (Accutane), a recognized human teratogen. Through the California Teratogen Information Service and Clinical Research Program, between 1983 and 2003, 106 pregnant women with first-trimester exposure to topical tretinoin were prospectively ascertained and followed. Birth outcomes, including pregnancy loss, major structural defects, and pre- and postnatal growth were compared to 389 similarly and prospectively ascertained women with no topical tretinoin exposure during pregnancy. Because a distinct pattern of malformation had already been described for isotretinoin, we also compared exposed (n = 62) and unexposed (n = 191) infants on the prevalence of a specific subset of minor malformations selected to represent the spectrum of defects comprising the retinoic acid embyopathy. There were no significant differences between groups in the proportion of pregnancies ending in spontaneous abortion (6.6% in exposed vs. 8.5% in unexposed; P = 0.53), or infants with major structural defects (2.2% in exposed vs. 1.2% in unexposed; P = 0.62). In addition, the groups were similar in birth weight, length and head circumference, and there were no significant differences between groups in length of gestation. Furthermore, the prevalence of one or more retinoic acid-specific minor malformations did not differ significantly between groups (12.9% in exposed vs. 9.9% in unexposed; P = 0.51). First-trimester topical tretinoin exposure in this study was not associated with an increased risk of any adverse pregnancy outcome evaluated. Specifically, there was no indication that topical tretinoin is associated with an increased risk for minor malformations that are consistent with the retinoic acid embryopathy. Although it is impossible to exclude the possibility that some women/infants may be uniquely susceptible to topical tretinoin exposure, this study provides further reassurance for women who are inadvertently exposed early in pregnancy. Copyright 2005 Wiley-Liss, Inc.

Effects of retinoids on ultraviolet-induced carcinogenesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Epstein, J.H.

The evidence for effects of the retinoids on UV-induced carcinogenesis is sparse. Clinical observations indicate that topical RA can cause significant regression of premalignant actinic keratoses. Also there is some evidence that this agent can cause dissolution of some basal cell epitheliomas. However this latter effect does not appear to be of therapeutic value. Systemic retinoids are of little value in the treatment of premalignant and malignant cutaneous lesions though 13-cis-retinoic acid might be of use in the basal cell nevus syndrome. Examination of the influence of the retinoids on photocarcinogenesis essentially has been confined to RA and animal experimentation.more » RA in nontoxic concentrations can both stimulate and inhibit photocarcinogenesis depending upon the circumstances of the study. The mechanisms of these responses are not clear. Influences on DNA synthesis directly and/or indirectly or on immune responses may be involved in both effects. Preliminary studies with oral 13-cis-retinoic acid have not demonstrated any effects to date on UV-induced skin cancer formation.« less

The efficacy of 9-cis retinoic acid in experimental models of cancer.

PubMed

Gottardis, M M; Lamph, W W; Shalinsky, D R; Wellstein, A; Heyman, R A

1996-01-01

9-cis retinoic acid (9-cis RA) is a retinoid receptor pan-agonist that binds with high affinity to both retinoic acid receptors (RARs) and retinoid X receptors (RXRs). Using a variety of in vivo and in vitro cancer models, we present experimental data that 9-cis RA has activity as a potential chemotherapeutic agent. Treatment of the human promyelocytic leukemia cell line HL-60 with 9-cis RA decreases cell proliferation, increases cell differentiation, and increases apoptosis. Induction of apoptosis correlates with an increase in tissue transglutaminase (type II) activity. In vivo, 9-cis RA induces complete tumor regression of an early passage human lip squamous cell carcinoma xenograft. Finally, 9-cis RA inhibits the anchorage-independent growth of the human breast cancer cell lines MCF-7 and LY2 (an antiestrogen-resistant MCF-7 variant). Transient co-transfection assays indicate that 9-cis RA inhibits estrogen receptor transcription of an ERE-tk-LUC reporter through RAR or RXR receptors. These data suggest that retinoid receptors can antagonize estrogen-dependent transcription and provides one possible mechanism for the inhibition of cell growth by 9-cis RA in breast cancer cell lines. In summary, these findings present evidence that 9-cis RA has a wide range of activities in human cancer models.

A risk assessment of topical tretinoin as a potential human developmental toxin based on animal and comparative human data.

PubMed

Johnson, E M

1997-03-01

Although topically applied all-trans-retinoic acid (tretinoin) undergoes minimal absorption and adds negligibly to normal endogenous levels, its safety in humans is occasionally questioned because oral ingestion of retinoids at therapeutic levels is known to entail teratogenic risks. To assess the actual potential for developmental toxicity from treatment with topical tretinoin. Risk assessments were conducted on four known human developmental toxicants (valproic acid, methotrexate, thalidomide, and isotretinoin) and a potential developmental toxicant (acetylsalicylic acid). The margin of safety for each chemical was calculated from the ratio of animal no-observed adverse effect levels to human lowest-observed adverse effect levels or estimated exposure doses. The derived safety margin of more than 100 for topical tretinoin (with 2% absorption) contrasted sharply with the near unity values for valproic acid, methotrexate, thalidomide, and isotretinoin and was larger than that for acetylsalicylic acid. These data support other epidemiologic and animal data that topical tretinoin is not a potential human developmental toxicant.

Retinoic Acid Isomers Facilitate Apolipoprotein E Production and Lipidation in Astrocytes through the Retinoid X Receptor/Retinoic Acid Receptor Pathway*

PubMed Central

Zhao, Jing; Fu, Yuan; Liu, Chia-Chen; Shinohara, Mitsuru; Nielsen, Henrietta M.; Dong, Qiang; Kanekiyo, Takahisa; Bu, Guojun

2014-01-01

Apolipoprotein E (apoE) is the major cholesterol transport protein in the brain. Among the three human APOE alleles (APOE2, APOE3, and APOE4), APOE4 is the strongest genetic risk factor for late-onset Alzheimer disease (AD). The accumulation of amyloid-β (Aβ) is a central event in AD pathogenesis. Increasing evidence demonstrates that apoE isoforms differentially regulate AD-related pathways through both Aβ-dependent and -independent mechanisms; therefore, modulating apoE secretion, lipidation, and function might be an attractive approach for AD therapy. We performed a drug screen for compounds that modulate apoE production in immortalized astrocytes derived from apoE3-targeted replacement mice. Here, we report that retinoic acid (RA) isomers, including all-trans-RA, 9-cis-RA, and 13-cis-RA, significantly increase apoE secretion to ∼4-fold of control through retinoid X receptor (RXR) and RA receptor. These effects on modulating apoE are comparable with the effects recently reported for the RXR agonist bexarotene. Furthermore, all of these compounds increased the expression of the cholesterol transporter ABCA1 and ABCG1 levels and decreased cellular uptake of Aβ in an apoE-dependent manner. Both bexarotene and 9-cis-RA promote the lipidation status of apoE, in which 9-cis-RA promotes a stronger effect and exhibits less cytotoxicity compared with bexarotene. Importantly, we showed that oral administration of bexarotene and 9-cis-RA significantly increases apoE, ABCA1, and ABCG1 levels in mouse brains. Taken together, our results demonstrate that RXR/RA receptor agonists, including several RA isomers, are effective modulators of apoE secretion and lipidation and may be explored as potential drugs for AD therapy. PMID:24599963

Inhibition of proliferation and induction of apoptosis in soft tissue sarcoma cells by interferon-α and retinoids

PubMed Central

Brodowicz, T; Wiltschke, C; Kandioler-Eckersberger, D; Grunt, T W; Rudas, M; Schneider, S M; Hejna, M; Budinsky, A; Zielinski, C C

1999-01-01

Uncontrolled proliferation and a defect of apoptosis constitute crucial elements in the development and progression of tumours. Among many other biological response modifiers known to influence these mechanisms, the efficacy of retinoids and interferons in the treatment of various malignant entities is currently matter of discussion. In the present study, we have investigated the effects of 9-cis-retinoic acid (9cRA), 13-cis-retinoic acid (13cRA), all-trans-retinoic acid (tRA) and interferon-α on proliferation and apoptosis of human soft tissue sarcoma (STS) cell lines HTB-82 (rhabdomyosarcoma), HTB-91 (fibrosarcoma), HTB-92 (liposarcoma), HTB-93 (synovial sarcoma) and HTB-94 (chondrosarcoma) in relation to p53 genotype as well as p53 expression. HTB-91, HTB-92 and HTB-94 STS cells exhibited mutant p53, whereas wild-type p53 was found in HTB-93 STS cells, and a normal p53 status in HTB-82 STS cells, carrying a silent point mutation only. Interferon-α, irrespective of p53 status, inhibited the proliferation of all five cell lines dose- and time-dependently. Similarly, 9cRA, 13cRA and tRA decreased the proliferation of HTB-82 and HTB-93 STS cells, whereas the proliferation of p53-mutated HTB-91, HTB-92 and HTB-94 STS cells remained unchanged. Furthermore, only 9cRA and tRA were capable of inducing apoptosis in HTB-82 and HTB-93 STS cells, whereas HTB-91, HTB-92 and HTB-94 STS cells did not undergo apoptosis under the influence of 9cRA or tRA. Retinoic acid receptor (RAR)-α and RAR-β mRNA were not detectable by Northern blot analysis in the five STS cell lines, whereas mRNA for the universal retinoic acid receptor, RAR-γ, was expressed in all STS cell lines indicating that retinoid resistance was not associated with a lack of RAR expression. Apoptosis was not induced by interferon-α or 13cRA in any of the five STS cell lines tested. Our results indicate that within the panel of tested STS cell lines, inhibition of proliferation and induction of apoptosis result from different mechanisms which differ in their dependence upon the presence of intact p53. © 1999 Cancer Research Campaign PMID:10424735

Neutrophils are immune cells preferentially targeted by retinoic acid in elderly subjects

PubMed Central

2010-01-01

Background The immune system gradually deteriorates with age and nutritional status is a major factor in immunosenescence. Of the many nutritional factors implicated in age-related immune dysfunction, vitamin A may be a good candidate, since vitamin A concentrations classically decrease during aging whereas it may possess important immunomodulatory properties via its active metabolites, the retinoic acids. This prompted us to investigate the immune response induced by retinoids in adults and elderly healthy subjects. Before and after oral supplementation with 13cis retinoic acid (0.5 mg/kg/day during 28 days), whole blood cells were phenotyped, and functions of peripheral blood mononuclear cells (PBMC) and polymorphonuclear cells (PMN) were investigated by flow cytometry and ELISA tests. Results In both young adults (n = 20, 25 ± 4 years) and older subjects (n = 20, 65 ± 4 years), retinoic acid supplementation had no effect on the distribution of leukocyte subpopulations or on the functions of PBMC (Il-2 and sIl-2R production, membrane expression of CD25). Concerning PMN, retinoic acid induced an increase in both spontaneous migration and cell surface expression of CD11b in the two different age populations, whereas bactericidal activity and phagocytosis remained unchanged. Conclusions We demonstrated that retinoic acid induces the same intensity of immune response between adult and older subjects, and more specifically affects PMN functions, i.e. adhesion and migration, than PBMC functions. PMID:20727130

9-cis-Retinoic Acid Promotes Cell Adhesion Through Integrin Dependent and Independent Mechanisms Across Immune Lineages

PubMed Central

Whelan, Jarrett T.; Chen, Jianming; Miller, Jabin; Morrow, Rebekah L.; Lingo, Joshuah D.; Merrell, Kaitlin; Shaikh, Saame Raza; Bridges, Lance C.

2012-01-01

Retinoids are essential in the proper establishment and maintenance of immunity. Although retinoids are implicated in immune related processes, their role in immune cell adhesion has not been well established. In this study, the effect of 9-cis-retinoic acid (9-cis-RA) on human hematopoietic cell adhesion was investigated. 9-cis-RA treatment specifically induced cell adhesion of the human immune cell lines HuT-78, NB4, RPMI 8866, and U937. Due to the prominent role of integrin receptors in mediating immune cell adhesion, we sought to evaluate if cell adhesion was integrin-dependent. By employing a variety of integrin antagonist including function-blocking antibodies and EDTA, we establish that 9-cis-RA prompts immune cell adhesion through established integrin receptors in addition to a novel integrin-independent process. The novel integrin-independent adhesion required the presence of retinoid and was attenuated by treatment with synthetic corticosteroids. Finally, we demonstrate that 9-cis-RA treatment of primary murine B-cells induces ex vivo adhesion that persists in the absence of integrin function. Our study is the first to demonstrate that 9-cis-retinoic acid influences immune cell adhesion through at least two functionally distinct mechanisms. PMID:22925918

Growth Suppression and Therapy Sensitization of Breast Cancer.

DTIC Science & Technology

1997-07-01

mutant jun. As shown in Figure 8, T47D breast cancer cells grown in the presence of 9- cis retinoic acid do become more sensitive to suppression by p53...SRI 1220. We have used the plasmid reactivation assay to demonstrate that repair of a cisplatin damaged plasmid is inhibited by 9- cis retinoic acid in...3 hr in vitro Sensitivity of T47D cells to 9- cis RA with 25 pM cisplatin) 120 --- 25- T47D 1220 M 100 - 11-gal O ,p53 "o 8.0 o. m 5 wR 80 T47D

Retinoids in pediatric onco-hematology: the model of acute promyelocytic leukemia and neuroblastoma.

PubMed

Masetti, Riccardo; Biagi, Carlotta; Zama, Daniele; Vendemini, Francesca; Martoni, Anna; Morello, William; Gasperini, Pietro; Pession, Andrea

2012-09-01

Retinoids are lipophilic compounds derived from vitamin A, which have been extensively studied in cancer prevention and therapy. In pediatric oncology, they are successfully used for the treatment of acute promyelocytic leukemia (APL) and high-risk neuroblastoma (HR-NBL). APL is a subtype of acute myeloid leukemia (AML) clinically characterized by a severe bleeding tendency with a highrisk of fatal hemorrhage. The molecular hallmark of this disease is the presence of the promyelocytic leukemia (PML)-retinoic acid receptor-α (RAR α) gene fusion that plays a critical role in promyelocytic leukemogenesis and represents the target of retinoid therapy. The introduction in the late 1980s of all-trans retinoic acid (ATRA) into the therapy of APL radically changed the management and the outcome of this disease. Presently, the standard front-line therapeutic approach for pediatric APL includes anthracycline-based chemotherapy and ATRA, leading to a complete remission in almost 90% of the patients. Neuroblastoma (NBL) is an aggressive childhood tumor derived from the peripheral neural crest. More than half of patients have a high-risk disease, with a poor outcome despite intensive multimodal treatment. Although the exact mechanism of action remains unclear, the introduction of 13-cis-retinoic acid (13-cis-RA) in the therapy of NBL has improved the prognosis of this disease. Currently, the standard treatment for HR-NBL consists of myeloablative therapy followed by autologous hematopoietic stem cell transplantation (HSCT) and maintenance with 13-cis-RA for the treatment of minimal residual disease, leading to a 3-year disease-free survival rate (DFS) of about 50%. In this paper the authors provide a review of the peer-reviewed literature on the role of retinoids in the treatment of pediatric APL and HR-NBL, summarizing the most relevant clinical trial results of the last decades, analyzing the ongoing trials, and investigating future therapeutic perspectives of children affected by these diseases.

Metabolism of oral 9-cis-retinoic acid in the human. Identification of 9-cis-retinoyl-beta-glucuronide and 9-cis-4-oxo-retinoyl-beta-glucuronide as urinary metabolites.

PubMed

Sass, J O; Masgrau, E; Saurat, J H; Nau, H

1995-09-01

Data from a number of investigators suggest that the 9-cis-isomer of RA1 (9-cis-RA) may be a promising agent in chemoprevention and treatment of certain types of cancer. Therefore, clinical studies on this retinoid have been initiated. However, up to now, no information has been published on the metabolism of 9-cis-RA in the human. Herein, we report the first data on retinoid metabolism after multiple administration of 9-cis-RA (20 mg/day po) to human volunteers. After 2 and 12-13 hr, plasma concentrations of 9-cis-RA and its metabolites 9,13-dicis-RA, 13-cis-RA, and all-trans-RA were low. In contrast, dosing with 13-cis-RA yielded much higher plasma retinoid levels. Effects on plasma retinol concentrations did not become obvious after any drug treatment. Several retinoid metabolites were found in the urine of 9-cis-RA-treated individuals, and 9-cis-RAG, as well as 9-cis-4-oxo-RAG, could be identified. After treatment with 9-cis-RA, high concentrations of the administered drug were found in the feces, along with comparably low concentrations of 13-cis-RA, 9,13-dicis-RA, and all-trans-RA. Our report indicates that 9-cis-RA is either eliminated much more rapidly than 13-cis-RA, or it is poorly absorbed, and presents the characterization of two urinary glucuronides.

Topical isotretinoin for melasma in Thai patients: a vehicle-controlled clinical trial.

PubMed

Leenutaphong, V; Nettakul, A; Rattanasuwon, P

1999-09-01

Melasma is an acquired hyperpigmentary disorder commonly seen in Orientals. Recently it has been demonstrated that tretinoin (all-trans-retinoic acid) can produce significant clinical improvement of melasma. However, moderate cutaneous side effects (retinoid dermatitis) occurred in a number of patients. To investigate the efficacy of topical 0.05 per cent isotretinoin gel (Isotrex) in the treatment of melasma in Thai patients. Thirty patients with moderate to severe melasma entered a 40-week, randomized, vehicle-controlled clinical trial in which they applied either 0.05 per cent isotretinoin gel, or its vehicle base together with a broad spectrum sunscreen (SPF 28) daily to the entire face. They were evaluated clinically (using Melasma Area and Severity Index), and colorimetrically (using our Melasma Area and Melanin Index). After 40 weeks, the average MASI and MAMI scores of the isotretinoin-treated group decreased by 68.2 per cent and 47 per cent respectively, while the corresponding control scores declined 60 per cent and 34 per cent. There was no statistically significant difference between the isotretinoin and vehicle groups. When the MASI and MAMI scores of each visit were compared to their baseline data, a statistically significant reduction of the score was first noted at weeks 4 and 12 respectively. Lightening of melasma, as determined clinically (MASI score), correlated well with pigmentation measurements (MAMI score). Side effects were limited to a mild transient "retinoid dermatitis" occurring in 27 per cent of isotretinoin-treated patients. Daily use of broad spectrum sunscreen has a significant lightening effect on melasma in Thai patients. However, there was no statistically significant difference between the isotretinoin and vehicle-treated group.

Disabled-2 Mediation of Retinoic Acid Cell Growth Arrest Signal in Breast Cancer

DTIC Science & Technology

2002-08-01

C. Cohen, L. E. Mendez , I. R. Horowitz, ylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. A. I Godwin, and X X. Xu, submitted for publication. T...trans., 9-cis-retinoic acid) and P- caro - forming units of adenovirus were added to the cells in medium with low tene were purchased from Sigma

13-cis Retinoic Acid Inhibits Development and Progression of Chronic Allograft Nephropathy

PubMed Central

Adams, Judith; Kiss, Eva; Arroyo, Ana B.V.; Bonrouhi, Mahnaz; Sun, Qiang; Li, Zhen; Gretz, Norbert; Schnitger, Anna; Zouboulis, Christos C.; Wiesel, Manfred; Wagner, Jürgen; Nelson, Peter J.; Gröne, Hermann-Josef

2005-01-01

Chronic allograft nephropathy is characterized by chronic inflammation and fibrosis. Because retinoids exhibit anti-proliferative, anti-inflammatory, and anti-fibrotic functions, the effects of low and high doses of 13-cis-retinoic acid (13cRA) were studied in a chronic Fisher344→Lewis transplantation model. In 13cRA animals, independent of dose (2 or 20 mg/kg body weight/day) and start (0 or 14 days after transplantation) of 13cRA administration, serum creatinine was significantly lower and chronic rejection damage was dramatically reduced, including subendothelial fibrosis of preglomerular vessels and chronic tubulointerstitial damage. The number of infiltrating mononuclear cells and their proliferative activity were significantly diminished. The mRNA expression of chemokines (MCP-1/CCL2, MIP-1α/CCL3, IP-10/CXCL10, RANTES/CCL5) and proteins associated with fibrosis (plasminogen activator inhibitor-1, transforming growth factor-β1, and collagens I and III) were strikingly lower in treated allografts. In vitro, activated peritoneal macrophages of 13cRA-treated rats showed a pronounced decrease in protein secretion of inflammatory cytokines (eg, tumor necrosis factor-α, interleukin-6). The suppression of the proinflammatory chemokine RANTES/CCL5 × 13cRA in fibroblasts could be mapped to a promoter module comprising IRF-1 and nuclear factor-κB binding elements, but direct binding of retinoid receptors to promoter elements could be excluded. In summary, 13cRA acted as a potent immunosuppressive and anti-fibrotic agent able to prevent and inhibit progression of chronic allograft nephropathy. PMID:15972972

In vitro retinoid binding and release from a collagen sponge material in a simulated intravaginal environment.

PubMed

Dorr, R T; Surwit, E A; Droegemueller, W; Alberts, D S; Meyskens, F L; Chvapil, M

1982-11-01

Four in vitro preparations were constructed to simulate the intravaginal release of two retinoids, all-trans-retinoic acid (t-RA) and 13-cis-retinoic acid (c-RA), from a 0.7% collagen sponge diaphragm insert. Four t-RA concentrations, 0.019, 0.05, 0.1, and 0.15% in methanol were added to the sponge. The release into an artificial vaginal fluid was monitored serially over 72 h by serial analysis for t-RA and c-RA using high-pressure liquid chromatography. In each preparation, retinoid release was immediate and noncontinuous. At 37 degrees C, the retinoids were stable for at least 48 h. Trans-retinoic acid was the predominant retinoid recovered. Only trace amounts of the cis-isomer were released. Peak t-RA levels were 20 microM after 0.01%, 60-80 microM after 0.05%, 100-200 microM after 0.1%, and 320 microM after 0.15%. When the vaginal fluid bath was changed after 5 h, no further significant retinoid release occurred. There was significant loss of up to 70% of the applied t-RA into the collagen sponge. The retinoid binding was concentration dependent (higher binding with higher concentrations) and was maximal only after 24 h of co-incubation. The discontinuous release of t-RA and the high degree of binding to collagen would seem to preclude use of the diaphragm insert as a vaginal drug delivery system, at least for retinoids.

Docking simulations suggest that all-trans retinoic acid could bind to retinoid X receptors.

PubMed

Tsuji, Motonori; Shudo, Koichi; Kagechika, Hiroyuki

2015-10-01

Retinoid X receptors (RXRs) are ligand-controlled transcription factors which heterodimerize with other nuclear receptors to regulate gene transcriptions associated with crucial biological events. 9-cis retinoic acid (9cRA), which transactivates RXRs, is believed to be an endogenous RXR ligand. All-trans retinoic acid (ATRA) is a natural ligand for retinoic acid receptors (RARs), which heterodimerize with RXRs. Although the concentration of 9cRA in tissues is very low, ATRA is relatively abundant and some reports show that ATRA activates RXRs. We computationally studied the possibility of ATRA binding to RXRs using two different docking methods with our developed programs to assess the binding affinities of naturally occurring retinoids. The simulations showed good correlations to the reported binding affinities of these molecules for RXRs and RARs.

Effects of isotretinoin treatment on cartilage and tendon thicknesses: an ultrasonographic study.

PubMed

Yıldızgören, Mustafa Turgut; Karataş Toğral, Arzu; Baki, Ali Erdem; Ekiz, Timur

2015-07-01

Effects of retinoic acid on collagen synthesis and cartilage have previously been shown. However, its effects on cartilage and tendons in humans have not been studied yet. Therefore, in order to provide a morphologic insight, the aim of this study was to measure femoral cartilage, Achilles and supraspinatus tendon thicknesses in patients under systemic isotretinoin treatment by using ultrasound. Fifteen patients (nine F, six M) who used isotretinoin for their acnes were included. All patients were treated with isotretinoin 0.5 mg/kg/day for the first month, and the dosage was escalated up to 1 mg/kg/day thereafter. Distal femoral cartilage, supraspinatus, and Achilles tendons thicknesses have been evaluated both before the treatment and at the end of the third month. Femoral cartilage thicknesses were assessed from three midpoints bilaterally; medial condyle, lateral condyle, and intercondylar area. Short/long-axis diameters and cross-sectional area of the Achilles tendons and axial tendon thicknesses of supraspinatus tendon were evaluated from the nondominant side. The mean age of the patients was 20.1 ± 4.9 years, and body mass index was 21.7 ± 2.5 kg/m(2). Although posttreatment cartilage measurements of 30 knees were lower for the three midpoints, it reached significance only for lateral condyle (p = 0.05). In addition, posttreatment tendon measurements were not statistically significant compared with pretreatment values (all p > 0.05). Systemic isotretinoin treatment seems to make cartilage thinner. Further studies considering histological and molecular evaluations with more sample sizes are awaited.

Spatiotemporal manipulation of retinoic acid activity in zebrafish hindbrain development via photo-isomerization.

PubMed

Xu, Lijun; Feng, Zhiping; Sinha, Deepak; Ducos, Bertrand; Ebenstein, Yuval; Tadmor, Arbel D; Gauron, Carole; Le Saux, Thomas; Lin, Shuo; Weiss, Shimon; Vriz, Sophie; Jullien, Ludovic; Bensimon, David

2012-09-01

All-trans retinoic acid (RA) is a key player in many developmental pathways. Most methods used to study its effects in development involve continuous all-trans RA activation by incubation in a solution of all-trans RA or by implanting all-trans RA-soaked beads at desired locations in the embryo. Here we show that the UV-driven photo-isomerization of 13-cis RA to the trans-isomer (and vice versa) can be used to non-invasively and quantitatively control the concentration of all-trans RA in a developing embryo in time and space. This facilitates the global or local perturbation of developmental pathways with a pulse of all-trans RA of known concentration or its inactivation by UV illumination. In zebrafish embryos in which endogenous synthesis of all-trans RA is impaired, incubation for as little as 5 minutes in 1 nM all-trans RA (a pulse) or 5 nM 13-cis RA followed by 1-minute UV illumination is sufficient to rescue the development of the hindbrain if performed no later than bud stage. However, if subsequent to this all-trans RA pulse the embryo is illuminated (no later than bud stage) for 1 minute with UV light (to isomerize, i.e. deactivate, all-trans RA), the rescue of hindbrain development is impaired. This suggests that all-trans RA is sequestered in embryos that have been transiently exposed to it. Using 13-cis RA isomerization with UV light, we further show that local illumination at bud stage of the head region (but not the tail) is sufficient to rescue hindbrain formation in embryos whose all-trans RA synthetic pathway has been impaired.

Conformational Analysis of Free and Bound Retinoic Acid

PubMed Central

Fu, Zheng; Li, Xue; Merz, Kenneth M.

2012-01-01

The conformational profiles of unbound all-trans and 9-cis retinoic acid (RA) have been determined using classical and quantum mechanical calculations. Sixty-six all-trans-RA (ATRA) and forty-eight 9-cis-RA energy minimum conformers were identified via HF/6-31G* geometry optimizations in vacuo. Their relative conformational energies were estimated utilizing the M06, M06-2x and MP2 methods combined with the 6-311+G(d,p), aug-cc-pVDZ and aug-cc-pVTZ basis sets, as well as complete basis set MP2 extrapolations using the latter two basis sets. Single-point energy calculations performed with the M06-2x density functional were found to yield similar results to MP2/CBS for the low-energy retinoic acid conformations. Not unexpectedly, the conformational propensities of retinoic acid were governed by the orientation and arrangement of the torsion angles associated with the polyene tail. We also used previously reported QM/MM X-ray refinement results on four ATRA-protein crystal structures plus one newly refined 9-cis-RA complex (PDB ID 1XDK) in order to investigate the conformational preferences of bound retinoic acid. In the re-refined RA conformers the conjugated double bonds are nearly coplanar, which is consistent with the global minimum identified by the Omega/QM method rather than the corresponding crystallographically determined conformations given in the PDB. Consequently, a 91.3% average reduction of the local strain energy in the gas phase, as well as 92.1% in PCM solvent, was observed using the QM/MM refined structures versus the PDB deposited RA conformations. These results thus demonstrate that our QM/MM X-ray refinement approach can significantly enhance the quality of X-ray crystal structures refined by conventional refinement protocols, thereby providing reliable drug-target structural information for use in structure-based drug discovery applications. PMID:22844234

9-cis-retinoic acid represses estrogen-induced expression of the very low density apolipoprotein II gene.

PubMed

Schippers, I J; Kloppenburg, M; Snippe, L; Ab, G

1994-11-01

The chicken very low density apolipoprotein II (apoVLDLII) gene is estrogen-inducible and specifically expressed in liver. We examined the possible involvement of the retinoid X receptor (RXR) and its ligand 9-cis-retinoic acid (9-cis-RA) in the activation of the apoVLDLII promoter. We first concentrated on a potential RXR recognition site, which deviates at only one position from a perfect direct A/GGGTCA repeat spaced by one nucleotide (DR-1) and was earlier identified as a common HNF-4/COUP-TF recognition site. However, band shift analysis revealed that this imperfect DR-1 motif does not interact with RXR alpha-homodimers. In accordance with this observation we found that this regulatory element does not mediate transactivation through RXR alpha in the presence of 9-cis-RA. However, our experiments revealed another, unexpected, effect of 9-cis-RA. Instead of stimulating, 9-cis-RA attenuated estrogen-induced expression of transfected estrogen-responsive VLDL-CAT reporter plasmids. This repression appeared to take place through the main estrogen response element (ERE) of the gene. Importantly, 9-cis-RA also strongly repressed the estrogen-induced expression of the endogenous apoVLDLII gene in cultured chicken hepatoma cells.

Accelerated Skeletal Maturation in Disorders of Retinoic Acid Metabolism: A Case Report and Focused Review of the Literature.

PubMed

Nilsson, O; Isoherranen, N; Guo, M H; Lui, J C; Jee, Y H; Guttmann-Bauman, I; Acerini, C; Lee, W; Allikmets, R; Yanovski, J A; Dauber, A; Baron, J

2016-11-01

Nutritional excess of vitamin A, a precursor for retinoic acid (RA), causes premature epiphyseal fusion, craniosynostosis, and light-dependent retinopathy. Similarly, homozygous loss-of-function mutations in CYP26B1, one of the major RA-metabolizing enzymes, cause advanced bone age, premature epiphyseal fusion, and craniosynostosis. In this paper, a patient with markedly accelerated skeletal and dental development, retinal scarring, and autism-spectrum disease is presented and the role of retinoic acid in longitudinal bone growth and skeletal maturation is reviewed. Genetic studies were carried out using SNP array and exome sequencing. RA isomers were measured in the patient, family members, and in 18 age-matched healthy children using high-performance liquid chromatography coupled to tandem mass spectrometry. A genomic SNP array identified a novel 8.3 megabase microdeletion on chromosome 10q23.2-23.33. The 79 deleted genes included CYP26A1 and C1 , both major RA-metabolizing enzymes. Exome sequencing did not detect any variants that were predicted to be deleterious in the remaining alleles of these genes or other known retinoic acid-metabolizing enzymes. The patient exhibited elevated plasma total RA (16.5 vs. 12.6±1.5 nM, mean±SD, subject vs. controls) and 13- cis RA (10.7 nM vs. 6.1±1.1). The findings support the hypothesis that elevated RA concentrations accelerate bone and dental maturation in humans. CYP26A1 and C1 haploinsufficiency may contribute to the elevated retinoic acid concentrations and clinical findings of the patient, although this phenotype has not been reported in other patients with similar deletions, suggesting that other unknown genetic or environmental factors may also contribute. © Georg Thieme Verlag KG Stuttgart · New York.

A High Throughput Phenotypic Screening reveals compounds that counteract premature osteogenic differentiation of HGPS iPS-derived mesenchymal stem cells

PubMed Central

Lo Cicero, Alessandra; Jaskowiak, Anne-Laure; Egesipe, Anne-Laure; Tournois, Johana; Brinon, Benjamin; Pitrez, Patricia R.; Ferreira, Lino; de Sandre-Giovannoli, Annachiara; Levy, Nicolas; Nissan, Xavier

2016-01-01

Hutchinson-Gilford progeria syndrome (HGPS) is a rare fatal genetic disorder that causes systemic accelerated aging in children. Thanks to the pluripotency and self-renewal properties of induced pluripotent stem cells (iPSC), HGPS iPSC-based modeling opens up the possibility of access to different relevant cell types for pharmacological approaches. In this study, 2800 small molecules were explored using high-throughput screening, looking for compounds that could potentially reduce the alkaline phosphatase activity of HGPS mesenchymal stem cells (MSCs) committed into osteogenic differentiation. Results revealed seven compounds that normalized the osteogenic differentiation process and, among these, all-trans retinoic acid and 13-cis-retinoic acid, that also decreased progerin expression. This study highlights the potential of high-throughput drug screening using HGPS iPS-derived cells, in order to find therapeutic compounds for HGPS and, potentially, for other aging-related disorders. PMID:27739443

A High Throughput Phenotypic Screening reveals compounds that counteract premature osteogenic differentiation of HGPS iPS-derived mesenchymal stem cells.

PubMed

Lo Cicero, Alessandra; Jaskowiak, Anne-Laure; Egesipe, Anne-Laure; Tournois, Johana; Brinon, Benjamin; Pitrez, Patricia R; Ferreira, Lino; de Sandre-Giovannoli, Annachiara; Levy, Nicolas; Nissan, Xavier

2016-10-14

Hutchinson-Gilford progeria syndrome (HGPS) is a rare fatal genetic disorder that causes systemic accelerated aging in children. Thanks to the pluripotency and self-renewal properties of induced pluripotent stem cells (iPSC), HGPS iPSC-based modeling opens up the possibility of access to different relevant cell types for pharmacological approaches. In this study, 2800 small molecules were explored using high-throughput screening, looking for compounds that could potentially reduce the alkaline phosphatase activity of HGPS mesenchymal stem cells (MSCs) committed into osteogenic differentiation. Results revealed seven compounds that normalized the osteogenic differentiation process and, among these, all-trans retinoic acid and 13-cis-retinoic acid, that also decreased progerin expression. This study highlights the potential of high-throughput drug screening using HGPS iPS-derived cells, in order to find therapeutic compounds for HGPS and, potentially, for other aging-related disorders.

A phase II study of 13-cis retinoic acid plus interferon alpha-2a in advanced stage penile carcinoma: an Eastern Cooperative Oncology Group study (E3893).

PubMed

Skeel, Roland T; Huang, Jie; Manola, Judith; Wilding, George; Dreicer, Robert; Walker, Paul; Muggia, Franco; Crawford, E David; Dutcher, Janice P; Loehrer, Patrick J

2003-01-01

Combined biological therapy with 13-cis-retinoic acid (13-cRA) and interferon alpha-2a (IFN alpha-2a) was reported to be highly effective in squamous cell carcinoma of the cervix and skin. Squamous cell carcinoma of the penis is rare in the United States, accounting for less than 1/2% of all male malignancies. Because of the association of infection with human papillomavirus with both carcinomas of the cervix and penis and their shared squamous cell histology, we carried out a phase II study of 13-cRA and IFN alpha-2a in carcinoma of the penis. Eighteen ambulatory patients with surgically unresectable, recurrent, and/or metastatic squamous cell carcinoma of the penis were treated with IFN alpha-2a, 3MU/day administered subcutaneously and 13-cRA, 1 mg/kg orally daily for at least eight weeks, unless intolerable toxicity occurred. One patient was ineligible; one patient withdrew prior to treatment. Among the 16 eligible, treated patients, there was one complete response. Fourteen patients had progressive disease as their only treatment effect. Two patients were unevaluable for tumor response because they had no follow-up tumor measurements. No unexpected treatment-related toxicities were found on study. The only common form of grade 3 toxicity was hypertriglyceridemia found in eight of the 17 patients (47%). No toxicities above grade 3 were observed. In contrast to its benefit in squamous cell carcinomas of the cervix and skin, the combination of 13-cRA and IFN alpha-2a has low efficacy in advanced carcinoma of the penis.

Simultaneous determination of all-trans and 13-cis retinoic acids and their 4-oxo metabolites by adsorption liquid chromatography after solid-phase extraction.

PubMed

Lefebvre, P; Agadir, A; Cornic, M; Gourmel, B; Hue, B; Dreux, C; Degos, L; Chomienne, C

1995-04-07

All-trans retinoic acid (all-trans RA), the active metabolite of vitamin A, has been demonstrated to be an efficient alternative to chemotherapy in the treatment of acute promyelocytic leukemia (APL), the AML3 subtype of the FAB cytological classification. Complete remission is obtained by inducing terminal granulocytic differentiation of the leukemic cells. To study all-trans RA pharmacokinetics in patients with APL, a rapid, precise and selective high-performance liquid chromatographic (HPLC) assay was developed. This method is easy and shows good repeatability (C.V. = 8.41-12.44%), reproducibility (C.V. = 9.19-14.73%), accuracy (C.V. = 3.5-11%) and sensitivity with a detection limit of 5 pmol/ml. The analysis is performed using normal-phase HPLC in an isocratic mode with UV detection after solid-phase extraction on octadecyl (C18) columns. The mobile phase is hexane-dichloromethane-dioxane (78:18:4, v/v) containing 1% acetic acid.

Pneumocystis carinii pneumonia: a late presentation following treatment for stage IV neuroblastoma.

PubMed

Clarke, Edward; Glaser, Adam W; Picton, Susan V

2003-09-01

This report describes a child who develops Pneumocystis carinii pneumonia 7 months after high-dose chemotherapy for stage IV neuroblastoma. In addition to chemotherapy the child had also been treated with abdominal radiotherapy and 13-cis-retinoic acid. Standard practice has been to treat patients with prophylactic co-trimoxazole for 3 months after high-dose therapy, but this report highlights the intensity and complexity of current treatment for stage IV neuroblastoma and the need to be aware of prolonged lymphopenia after such treatment.

Low-dose oral isotretinoin versus topical retinoic acid for photoaging: a randomized, comparative study.

PubMed

Bagatin, Edileia; Guadanhim, Lilia R S; Enokihara, Milvia M S S; Sanudo, Adriana; Talarico, Sérgio; Miot, Helio A; Gibson, Lawrence

2014-01-01

Oral isotretinoin (ISO) is the only drug which promotes prolonged remission or cure of severe acne. It also has other properties, supporting its use for non-acne indications. Retinoic acid (RA) is gold standard treatment for photoaging. ISO for photoaging treatment was reported in non-controlled trials as alternative to RA, which causes skin irritation. To compare clinical, histological, and immunohistochemical effects of low-dose ISO and 0.05% topical RA to treat photoaging. Randomized, comparative, evaluator-blinded, single-center study. Twenty-four healthy, Caucasian, 50 to 75-year-old men and women (menopausal or sterilized) with advanced photoaging were included. Twelve subjects received ISO, 20 mg/day, and 12 subjects were treated with RA cream, for six months; both treatments were administered every other day, and moisturizer and sunscreen were also used. Outcome measures included patient assessments, blinded photographic evaluations, Life Quality Index, histological (HE, Verhoeff) and immunohistochemical (p53, collagen type I) evaluations, adverse events, liver function, lipid profile, and blood count. Statistical analysis with generalized estimating equations and repeated measures ANOVA tests was used. Eleven subjects in each group completed the study. Patient and photographic assessments showed overall improvement in skin appearance. Quality-of-life scores were reduced for all subjects. Histological analysis revealed corneal layer diminution, epidermal thickness increase, and elastosis reduction. Immunohistochemical findings revealed significant epidermal p53 reduction and dermal collagen 1 increase. No differences were found between groups; laboratory tests showed no significant alterations. Despite being safe and effective, low-dose ISO was not superior to 0.05% RA for advanced photoaging treatment. © 2013 The International Society of Dermatology.

Adjuvant potential of low dose all-trans retinoic acid during oral typhoid vaccination in Zambian men

PubMed Central

Lisulo, M M; Kapulu, M C; Banda, R; Sinkala, E; Kayamba, V; Sianongo, S; Kelly, P

2014-01-01

There is an urgent need to identify ways of enhancing the mucosal immune response to oral vaccines. Rotavirus vaccine protection is much lower in Africa and Asia than in industrialized countries, and no oral vaccine has efficacy approaching the best systemic vaccines. All-trans retinoic acid (ATRA) up-regulates expression of α4β7 integrin and CCR9 on lymphocytes in laboratory animals, increasing their gut tropism. The aim of this study was to establish the feasibility of using ATRA as an oral adjuvant for oral typhoid vaccination. In order to establish that standard doses of oral ATRA can achieve serum concentrations greater than 10 nmol/l, we measured ATRA, 9-cis and 13-cis retinoic acid in serum of 14 male volunteers before and 3 h after 10 mg ATRA. We then evaluated the effect of 10 mg ATRA given 1 h before, and for 7 days following, oral typhoid vaccine in eight men, and in 24 men given various control interventions. We measured immunoglobulin (Ig)A directed against lipopolysaccharide (LPS)and protein preparations of vaccine antigens in whole gut lavage fluid (WGLF) and both IgA and IgG in serum, 1 day prior to vaccination and on day 14. Median [interquartile range (IQR)] Cmax was 26·2 (11·7–39·5) nmol/l, with no evidence of cumulation over 8 days. No adverse events were observed. Specific IgA responses to LPS (P = 0·02) and protein (P = 0·04) were enhanced in WGLF, but no effect was seen on IgA or IgG in serum. ATRA was well absorbed, well tolerated and may be a promising candidate oral adjuvant. PMID:24237035

Anti-tumor effects of retinoids combined with trastuzumab or tamoxifen in breast cancer cells: induction of apoptosis by retinoid/trastuzumab combinations.

PubMed

Koay, Debbie C; Zerillo, Cynthia; Narayan, Murli; Harris, Lyndsay N; DiGiovanna, Michael P

2010-01-01

HER2 and estrogen receptor (ER) are important in breast cancer and are therapeutic targets of trastuzumab (Herceptin) and tamoxifen, respectively. Retinoids inhibit breast cancer growth, and modulate signaling by HER2 and ER. We hypothesized that treatment with retinoids and simultaneous targeting of HER2 and/or ER may have enhanced anti-tumor effects. The effects of retinoids combined with trastuzumab or tamoxifen were examined in two human breast cancer cell lines in culture, BT474 and SKBR3. Assays of proliferation, apoptosis, differentiation, cell cycle distribution, and receptor signaling were performed. In HER2-overexpressing/ER-positive BT474 cells, combining all-trans retinoic acid (atRA) with tamoxifen or trastuzumab synergistically inhibited cell growth, and altered cell differentiation and cell cycle. Only atRA/trastuzumab-containing combinations induced apoptosis. BT474 and HER2-overexpressing/ER-negative SKBR3 cells were treated with a panel of retinoids (atRA, 9-cis-retinoic acid, 13-cis-retinoic acid, or N-(4-hydroxyphenyl) retinamide (fenretinide) (4-HPR)) combined with trastuzumab. In BT474 cells, none of the single agents except 4-HPR induced apoptosis, but again combinations of each retinoid with trastuzumab did induce apoptosis. In contrast, the single retinoid agents did cause apoptosis in SKBR3 cells; this was only modestly enhanced by addition of trastuzumab. The retinoid drug combinations altered signaling by HER2 and ER. Retinoids were inactive in trastuzumab-resistant BT474 cells. Combining retinoids with trastuzumab maximally inhibits cell growth and induces apoptosis in trastuzumab-sensitive cells. Treatment with such combinations may have benefit for breast cancer patients.

No association between endogenous retinoic acid and human papillomavirus clearance or incident cervical lesions in Brazilian women

PubMed Central

Siegel, Erin M.; Salemi, Jason L.; Craft, Neal E.; Villa, Luisa L.; Ferenczy, Alex; Franco, Eduardo L.; Giuliano, Anna R.

2010-01-01

Background Although oncogenic human papillomavirus (HPV) infections have been established as the necessary cause of cervical cancer, most HPV infections are transient and rarely progress to squamous cervical lesions. The activity of HPV is tightly associated with epithelial cell differentiation; therefore regulators of differentiation, such as retinoic acid, have been considered targets for the prevention of HPV-associated squamous intraepithelial lesion (SIL) development. Purpose The purpose of this study was to determine the association between circulating retinoic acid (RA) and early events in cervical carcinogenesis, specifically type-specific HPV clearance and SIL detection. Methods Archived blood samples from 643 women participating in the Ludwig-McGill Cohort in São Paulo, Brazil were analyzed by high-pressure liquid chromatography for three RA isomers (all-trans, 13-cis, and 9-cis RA). A type-specific HPV clearance event was defined as two consecutive visits negative for that HPV type during follow-up for the 364 HPV positive women. Among the 643 women in this analysis, 78 were diagnosed with incident SIL. Results The probability of clearing an oncogenic HPV infection was not significantly different across RA isomer quartiles. There was a suggestion that increasing all-trans RA increased rate of non-oncogenic HPV clearance (p-trend=0.05). There was no association observed between serum RA levels and incident SIL. Conclusions Our results suggest that elevated circulating RA isomer levels do not increase rates of HPV clearance or reduce risk of incident SIL. The role of RA in the inhibition of HPV induced carcinogenesis, as demonstrated in vitro, lacks confirmatory evidence within epidemiologic studies among women. PMID:20606041

Molecular mechanism of 9-cis-retinoic acid inhibition of adipogenesis in 3T3-L1 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sagara, Chiaki; Takahashi, Katsuhiko; Kagechika, Hiroyuki

2013-03-29

Highlights: ► We examined the effects of 9-cis-RA on adipogenesis in mouse preadipocyte 3T3-L1. ► 9-cis-RA inhibited lipid accumulation in adipogenetically-induced 3T3-L1 cells. ► A RXR pan-antagonist suppressed the inhibitory effects of 9-cis-RA on adipogenesis. ► This antagonist had no effects on RXRα and PPARγ levels in 9-cis-RA-treated cells. ► 9-cis-RA-induced decrease in both RXRα and PPARγ was independent of RXR activation. -- Abstract: Retinoic acid (RA) signaling is mediated by specific nuclear hormone receptors. Here we examined the effects of 9-cis-RA on adipogenesis in mouse preadipocyte 3T3-L1 cells. 9-cis-RA inhibits the lipid accumulation of adipogenetically induced 3T3-L1 cells. Themore » complex of retinoid X receptor α (RXRα) with peroxisome proliferator-activated receptor γ (PPARγ) is a major transcription factor in the process of adipogenesis, and the levels of these molecules were decreased by 9-cis-RA treatment. A RXR pan-antagonist suppressed 9-cis-RA’s inhibitory effects on adipogenesis, but not on the intracellular levels of both RXRα and PPARγ. These results suggest that 9-cis-RA could inhibit adipogenesis by activating RXR, and decrease both RXR and PPARγs levels in a RXR activation-independent manner.« less

A sensitive and specific method for measurement of multiple retinoids in human serum with UHPLC-MS/MS

PubMed Central

Arnold, Samuel L. M.; Amory, John K.; Walsh, Thomas J.; Isoherranen, Nina

2012-01-01

Retinol (vitamin A) circulates at 1–4 μM concentration and is easily measured in serum. However, retinol is biologically inactive. Its metabolite, retinoic acid (RA), is believed to be responsible for biological effects of vitamin A, and hence the measurement of retinol concentrations is of limited value. A UHPLC-MS/MS method using isotope-labeled internal standards was developed and validated for quantitative analysis of endogenous RA isomers and metabolites. The method was used to measure retinoids in serum samples from 20 healthy men. In the fed state, the measured concentrations were 3.1 ± 0.2 nM for atRA, 0.1 ± 0.02 nM for 9-cisRA, 5.3 ± 1.3 nM for 13-cisRA, 0.4 ± 0.4 nM for 9,13-dicisRA, and 17.2 ± 6.8 nM for 4oxo-13-cisRA. The concentrations of the retinoids were not significantly different when measured after an overnight fast (3.0 ± 0.1 nM for atRA, 0.09 ± 0.01nM for 9-cisRA, 3.9 ± 0.2 nM for 13-cisRA, 0.3 ± 0.1 nM for 9,13-dicisRA, and 11.9 ± 1.6 nM for 4oxo-13-cisRA). 11-cisRA and 4OH-RA were not detected in human serum. The high sensitivity of the MS/MS method combined with the UHPLC separation power allowed detection of endogenous 9-cisRA and 4oxo-atRA for the first time in human serum. PMID:22192917

Post-surgical treatment of thyroid carcinoma in dogs with retinoic acid 9 cis improves patient outcome

PubMed Central

Castillo, V.; Pessina, P.; Hall, P.; Blatter, M.F. Cabrera; Miceli, D.; Arias, E. Soler; Vidal, P.

2016-01-01

The objective of the present study was to compare the effects of isotretinoin 9-cis (RA9-cis) as a post-surgery treatment of thyroid carcinoma to a traditional treatment (doxorubicin) and no treatment. Owners who did not want their dogs to receive treatment were placed into the control group A (GA; n=10). The remaining dogs were randomly placed into either group B (GB; n=12) and received doxorubicin at a dose of 30 mg/m2 every three weeks, for six complete cycles or group C (GC; n=15) and treated with RA9-cis at a dose of 2 mg/kg/day for 6 months. The time of the recurrence was significantly shorter in the GA and GB compared to GC (P=0.0007; P=0.0015 respectively), while we did not detect differences between GA and GB. The hazard ratio of recurrence between GA and GB compared to GC were 7.25 and 5.60 times shorter, respectively. We did not detect any differences between the other groups. The risk ratio of recurrence was 2.0 times higher in GA compared to GC and 2.1 times higher in GB compared to GC. The type of carcinoma had an effect on time of survival with follicular carcinomas having an increased mean survival time than follicular-compact carcinomas (P<0.0001) and follicular-compact carcinomas had a longer mean survival time than compact carcinomas. The interaction among treatment and type was significant, but survival time in follicular carcinomas did not differ between treatments. In follicular-compact carcinomas the survival time of GC was greater than GB (P<0.05), but we did not detect a difference between GA and GB. In conclusion, this study shows that the use of surgery in combination with RA9-cis treatment significantly increases survival rate and decreases the time to tumor recurrence when compared to doxorubicin treated or untreated dogs. The histological type of carcinoma interacted with treatment for time to recurrence and survival time, with more undifferentiated carcinomas having a worse prognosis than differentiated carcinomas. PMID:26862515

Retinoic acid and nitric oxide promote cell proliferation and differentially induce neuronal differentiation in vitro in the cnidarian Renilla koellikeri.

PubMed

Estephane, Djoyce; Anctil, Michel

2010-10-01

Retinoic acid (RA) and nitric oxide (NO) are known to promote neuronal development in both vertebrates and invertebrates. Retinoic acid receptors appear to be present in cnidarians and NO plays various physiological roles in several cnidarians, but there is as yet no evidence that these agents have a role in neural development in this basal metazoan phylum. We used primary cultures of cells from the sea pansy Renilla koellikeri to investigate the involvement of these signaling molecules in cnidarian cell differentiation. We found that 9-cis RA induce cell proliferation in dose- and time-dependent manners in dishes coated with polylysine from the onset of culture. Cells in cultures exposed to RA in dishes devoid of polylysine were observed to differentiate into epithelium-associated cells, including sensory cells, without net gain in cell density. NO donors also induce cell proliferation in polylysine-coated dishes, but induce neuronal differentiation and neurite outgrowth in uncoated dishes. No other cell type undergoes differentiation in the presence of NO. These observations suggest that in the sea pansy (1) cell adhesion promotes proliferation without morphogenesis and this proliferation is modulated positively by 9-cis RA and NO, (2) 9-cis RA and NO differentially induce neuronal differentiation in nonadherent cells while repressing proliferation, and (3) the involvement of RA and NO in neuronal differentiation appeared early during the evolutionary emergence of nervous systems. 2010 Wiley Periodicals, Inc.

A retinoic acid response element that overlaps an estrogen response element mediates multihormonal sensitivity in transcriptional activation of the lactoferrin gene.

PubMed

Lee, M O; Liu, Y; Zhang, X K

1995-08-01

The lactoferrin gene is highly expressed in many different tissues, and its expression is controlled by different regulators. In this report, we have defined a retinoic acid response element (RARE) in the 5'-flanking region of the lactoferrin gene promoter. The lactoferrin-RARE is composed of two AGGTCA-like motifs arranged as a direct repeat with 1-bp spacing (DR-1). A gel retardation assay demonstrated that it bound strongly with retinoid X receptor (RXR) homodimers and RXR-retinoic acid receptor (RAR) heterodimers as well as chicken ovalbumin upstream promoter transcription factor (COUP-TF) orphan receptor. In CV-1 cells, the lactoferrin-RARE linked with a heterologous thymidine kinase promoter was strongly activated by RXR homodimers in response to 9-cis-retinoic acid (9-cis-RA) but not to all-trans-RA. When the COUP-TF orphan receptor was cotransfected, the 9-cis-RA-induced RXR homodimer activity was strongly repressed. A unique feature of the lactoferrin-RARE is that it has an AGGTCA-like motif in common with an estrogen-responsive element (ERE). The composite RARE/ERE contributes to the functional interaction between retinoid receptors and the estrogen receptor (ER) and their ligands. In CV-1 cells, cotransfection of the retinoid and estrogen receptors led to mutual inhibition of the other's activity, while an RA-dependent inhibition of ER activity was observed in breast cancer cells. Furthermore, the lactoferrin-RARE/ERE showed differential transactivation activity in different cell types. RAs could activate the lactoferrin-RARE/ERE in human leukemia HL-60 cells and U937 cells but not in human breast cancer cells. By gel retardation analyses, we demonstrated that strong binding of the endogenous COUP-TF in breast cancer cells to the composite element contributed to diminished RA response in these cells. Thus, the lactoferrin-RARE/ERE functions as a signaling switch module that mediates multihormonal responsiveness in the regulation of lactoferrin gene expression.

Vitamin A Metabolism: An Update

PubMed Central

D’Ambrosio, Diana N.; Clugston, Robin D.; Blaner, William S.

2011-01-01

Retinoids are required for maintaining many essential physiological processes in the body, including normal growth and development, normal vision, a healthy immune system, normal reproduction, and healthy skin and barrier functions. In excess of 500 genes are thought to be regulated by retinoic acid. 11-cis-retinal serves as the visual chromophore in vision. The body must acquire retinoid from the diet in order to maintain these essential physiological processes. Retinoid metabolism is complex and involves many different retinoid forms, including retinyl esters, retinol, retinal, retinoic acid and oxidized and conjugated metabolites of both retinol and retinoic acid. In addition, retinoid metabolism involves many carrier proteins and enzymes that are specific to retinoid metabolism, as well as other proteins which may be involved in mediating also triglyceride and/or cholesterol metabolism. This review will focus on recent advances for understanding retinoid metabolism that have taken place in the last ten to fifteen years. PMID:21350678

Combination of 13 cis-retinoic acid and tolfenamic acid induces apoptosis and effectively inhibits high-risk neuroblastoma cell proliferation.

PubMed

Shelake, Sagar; Eslin, Don; Sutphin, Robert M; Sankpal, Umesh T; Wadwani, Anmol; Kenyon, Laura E; Tabor-Simecka, Leslie; Bowman, W Paul; Vishwanatha, Jamboor K; Basha, Riyaz

2015-11-01

Chemotherapeutic regimens used for the treatment of Neuroblastoma (NB) cause long-term side effects in pediatric patients. NB arises in immature sympathetic nerve cells and primarily affects infants and children. A high rate of relapse in high-risk neuroblastoma (HRNB) necessitates the development of alternative strategies for effective treatment. This study investigated the efficacy of a small molecule, tolfenamic acid (TA), for enhancing the anti-proliferative effect of 13 cis-retinoic acid (RA) in HRNB cell lines. LA1-55n and SH-SY5Y cells were treated with TA (30μM) or RA (20μM) or both (optimized doses, derived from dose curves) for 48h and tested the effect on cell viability, apoptosis and selected molecular markers (Sp1, survivin, AKT and ERK1/2). Cell viability and caspase activity were measured using the CellTiter-Glo and Caspase-Glo kits. The apoptotic cell population was determined by flow cytometry with Annexin-V staining. The expression of Sp1, survivin, AKT, ERK1/2 and c-PARP was evaluated by Western blots. The combination therapy of TA and RA resulted in significant inhibition of cell viability (p<0.0001) when compared to individual agents. The anti-proliferative effect is accompanied by a decrease in Sp1 and survivin expression and an increase in apoptotic markers, Annexin-V positive cells, caspase 3/7 activity and c-PARP levels. Notably, TA+RA combination also caused down regulation of AKT and ERK1/2 suggesting a distinct impact on survival and proliferation pathways via signaling cascades. This study demonstrates that the TA mediated inhibition of Sp1 in combination with RA provides a novel therapeutic strategy for the effective treatment of HRNB in children. Copyright © 2015 Elsevier Ltd. All rights reserved.

9-Cis-Retinoic Acid Induces Growth Inhibition in Retinoid-Sensitive Breast Cancer and Sea Urchin Embryonic Cells via Retinoid X Receptor α and Replication Factor C3

PubMed Central

Maeng, Sejung; Kim, Gil Jung; Choi, Eun Ju; Yang, Hyun Ok; Lee, Dong-Sup

2012-01-01

There is widespread interest in defining factors and mechanisms that suppress the proliferation of cancer cells. Retinoic acid (RA) is a potent suppressor of mammary cancer and developmental embryonic cell proliferation. However, the molecular mechanisms by which 9-cis-RA signaling induces growth inhibition in RA-sensitive breast cancer and embryonic cells are not apparent. Here, we provide evidence that the inhibitory effect of 9-cis-RA on cell proliferation depends on 9-cis-RA-dependent interaction of retinoid X receptor α (RXRα) with replication factor C3 (RFC3), which is a subunit of the RFC heteropentamer that opens and closes the circular proliferating cell nuclear antigen (PCNA) clamp on DNA. An RFC3 ortholog in a sea urchin cDNA library was isolated by using the ligand-binding domain of RXRα as bait in a yeast two-hybrid screening. The interaction of RFC3 with RXRα depends on 9-cis-RA and bexarotene, but not on all-trans-RA or an RA receptor (RAR)-selective ligand. Truncation and mutagenesis experiments demonstrated that the C-terminal LXXLL motifs in both human and sea urchin RFC3 are critical for the interaction with RXRα. The transient interaction between 9-cis-RA-activated RXRα and RFC3 resulted in reconfiguration of the PCNA-RFC complex. Furthermore, we found that knockdown of RXRα or overexpression of RFC3 impairs the ability of 9-cis-RA to inhibit proliferation of MCF-7 breast cancer cells and sea urchin embryogenesis. Our results indicate that 9-cis-RA-activated RXRα suppresses the growth of RA-sensitive breast cancer and embryonic cells through RFC3. PMID:22949521

Retinoic acid stability in stem cell cultures.

PubMed

Sharow, Kyle A; Temkin, Boris; Asson-Batres, Mary Ann

2012-01-01

It has been reported that retinoids, such as retinoic acid (RA) and retinol (ROL), dissolved in aqueous solutions are susceptible to oxidative damage when exposed to light, air, and relatively high temperatures, conditions that are normal for culturing stem cells. Thus, questions arise regarding the interpretation of results obtained from studies of mouse embryonic stem cells exposed to retinoids because their isomerization state, their stability in culture conditions, and their interactions with other potential differentiation factors in growth media could influence developmental processes under study. Media samples were supplemented with retinoids and exposed to cell culture conditions with and without mouse embryonic stem cells (mESC), and retinoids were extracted and analyzed using HPLC. To determine whether retinoids are stable in media supplemented with fetal bovine serum (FBS) or in chemically-defined, serum-free media, mESC adapted to each type of growth media were investigated. Studies reported here indicate there was little loss or isomerization of at-RA, 9-cis-RA, 13-cis-RA, or ROL in cell cultures grown in serum-supplemented media when cell cultures were maintained in the dark and manipulated and observed under yellow light. In contrast, the stability of both at-RA and ROL were determined to be greatly reduced in serum-free media as compared with serum-supplemented media. Addition of 6 mg/ml bovine serum albumin was found to stabilize retinoids in serum-free media. It was also determined that ROL is less stable than RA in cell culture conditions.

Determination of highly protein bound drugs in plasma using high-performance liquid chromatography and column switching, exemplified by the retinoids.

PubMed

Wyss, R; Bucheli, F

1988-12-02

During method development for the determination of either isotretinoin, tretinoin and their 4-oxo-metabolites, or etretinate, acitretin and 13-cis-acitretin in plasma using high-performance liquid chromatography and column switching, recovery problems arose, when undiluted plasma samples were injected directly onto the precolumn. These recovery problems may be due to the strong binding of the retinoids to different plasma proteins. Measures to overcome this strong protein binding, such as variation of the injection solution composition and the purge mobile phase, were systematically investigated. Best recoveries were obtained by diluting of plasma with 9 mM sodium hydroxide-acetonitrile (8:2, v/v) and protein precipitation with ethanol for the isotretinoin and etretinate series, respectively, in combination with the use of a purge mobile phase containing ammonium acetate and 10-20% acetonitrile. Less effective was the use of a longer precolumn or heating of the precolumn.

Targeting Notch pathway induces growth inhibition and differentiation of neuroblastoma cells.

PubMed

Ferrari-Toninelli, Giulia; Bonini, Sara Anna; Uberti, Daniela; Buizza, Laura; Bettinsoli, Paola; Poliani, Pietro Luigi; Facchetti, Fabio; Memo, Maurizio

2010-12-01

High-risk neuroblastoma is a severe pediatric tumor characterized by poor prognosis. Understanding the molecular mechanisms involved in tumor development and progression is strategic for the improvement of pharmacological therapies. Notch was recently proposed as a pharmacological target for the therapy of several cancers and is emerging as a new neuroblastoma-related molecular pathway. However, the precise role played by Notch in this cancer remains to be studied extensively. Here, we show that Notch activation by the Jagged1 ligand enhances the proliferation of neuroblastoma cells, and we propose the possible use of Notch-blocking γ-secretase inhibitors (GSIs) in neuroblastoma therapy. Two different GSIs, Compound E and DAPT, were tested alone or in combination with 13-cis retinoic acid (RA) on neuroblastoma cell lines. SH-SY5Y and IMR-32 cells were chosen as paradigms of lower and higher malignancy, respectively. Used alone, GSIs induced complete cell growth arrest, promoted neuronal differentiation, and significantly reduced cell motility. The combination of GSIs and 13-cis RA resulted in the enhanced growth inhibition, differentiation, and migration of neuroblastoma cells. In summary, our data suggest that a combination of GSIs with 13-cis RA offers a therapeutic advantage over a single agent, indicating a potential novel therapy for neuroblastoma.

Classical dendritic cells mediate fibrosis directly via the retinoic acid pathway in severe eye allergy

PubMed Central

Ahadome, Sarah D.; Mathew, Rose; Reyes, Nancy J.; Mettu, Priyatham S.; Cousins, Scott W.; Calder, Virginia L.; Saban, Daniel R.

2016-01-01

Fibrosis is a shared end-stage pathway to lung, liver, and heart failure. In the ocular mucosa (conjunctiva), fibrosis leads to blindness in trachoma, pemphigoid, and allergy. The indirect fibrogenic role of DCs via T cell activation and inflammatory cell recruitment is well documented. However, here we demonstrate that DCs can directly induce fibrosis. In the mouse model of allergic eye disease (AED), classical CD11b+ DCs in the ocular mucosa showed increased activity of aldehyde dehydrogenase (ALDH), the enzyme required for retinoic acid synthesis. In vitro, CD11b+ DC–derived ALDH was associated with 9-cis-retinoic acid ligation to retinoid x receptor (RXR), which induced conjunctival fibroblast activation. In vivo, stimulating RXR led to rapid onset of ocular mucosal fibrosis, whereas inhibiting ALDH activity in DCs or selectively depleting DCs markedly reduced fibrosis. Collectively, these data reveal a profibrotic ALDH-dependent pathway by DCs and uncover a role for DC retinoid metabolism. PMID:27595139

Comparison of Autologous Serum Versus Preservative Free Artificial Tear in Patients with Dry Eyes Due to Systemic Isotretinoin Therapy.

PubMed

Yılmaz, Uğur; Küçük, Erkut; Koç, Çağdaş; Gökler, Enes

2017-06-01

To investigate dry eye development in the patients receiving systemic retinoic acid therapy and to compare effectiveness of Autologous Serum (AS) and preservative free artificial tear (PFAT) in the patients with dry eye disease. This prospective, crossover, double blind study was conducted on patients who have dry eyes due to systemic isotretinoin treatment for different indications. Patients detected as having dry eye during systemic isotretinoin treatment were included to our study. At baseline, 1 and 2 month of study, detailed ocular examination, best corrected visual acuity measurement, intraocular pressure measurement, and Tear Break-up Time (TBUT) and Schirmer Test (ST) without topical anesthesia were performed. We compared the efficacy of AS and PFAT. To accomplish crossover after the first month, treatment given to each patient was switched to the other treatment. Statistical analysis was measured using SPSS version 20.0. p values of < 0.05 were considered as statistically significant. At the end of the first month, there was a significant improvement for the TBUT test in both AS and PFAT groups compared to baseline (respectively p < 0.001, p < 0.001). TBUT was found to be significantly higher in the AS group compared to the PFAT group at the end of the first month (p < 0.001). At the end of the second month, TBUT was found to be significantly higher in the AS group compared to the PFAT group at the posttreatment time (p < 0.001). There was a significant OSDI score decreasing in both groups compared to that reported previously at the end of the first and second months (respectively p < 0.001, p < 0.001). OSDI score decreasing was more significant in the AS group compared to the PFAT group at both time points (respectively p < 0.001, p < 0.001). AS may be an effective alternative to PFAT in the treatment of dry eye developed during isotretinoin use.

Effects of retinoids on differentiation, lipid metabolism, epidermal growth factor, and low-density lipoprotein binding in squamous carcinoma cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ponec, M.; Weerheim, A.; Havekes, L.

The relationship among keratinocyte differentiation capacity, lipid synthesis, low-density lipoprotein (LDL) metabolism, plasma membrane composition, and epidermal growth factor (EGF) binding has been studied in SCC-12F2 cells. The differentiation capacity of the cells, i.e., ionophore-induced cornified envelope formation, was inhibited by various retinoids and stimulated by hydrocortisone. Retinoids that caused a significant reduction of cornified envelope formation, i.e., retinoic acid and 13-cis-retinoic acid, caused only minor changes in lipid synthesis and plasma membrane composition. Arotinoid ethylsulfone, having a minor effect on cornified envelope formation, caused a drastic inhibition of cholesterol synthesis resulting in changes in the plasma membrane composition. Hydrocortisonemore » stimulated cornified envelope formation but had only minor effects on lipid synthesis and plasma membrane composition. Of all retinoids tested, only arotinoid ethylsulfone caused a drastic increase in EGF binding, while hydrocortisone had no effect. These results clearly demonstrate that the plasma membrane composition is not related to keratinocyte differentiation capacity, but most likely does determine EGF binding. Furthermore, EGF binding does not determine keratinocyte differentiation capacity.« less

Regeneration of the gut requires retinoic acid in the budding ascidian Polyandrocarpa misakiensis.

PubMed

Kaneko, Nagamoto; Katsuyama, You; Kawamura, Kazuo; Fujiwara, Shigeki

2010-06-01

The protochordate ascidian Polyandrocarpa misakiensis has a striking ability to regenerate. When the posterior half of the adult body is amputated, the anterior half completely loses the esophagus, stomach and intestine. These organs are reconstituted in a week. Histological observation revealed that the regeneration involves transdifferentiation of the atrial epithelium near the cut surface. The morphological features of the gut primordium were similar to those observed in the developing bud of this species. Inhibitors of the synthesis of retinoic acid (RA) suppressed the formation of the gut. 13-cis RA rescued the regenerates from the inhibitor-induced hypoplasia. These results suggest that RA is required for the regeneration of the gut. A gene encoding the RA receptor (Pm-RAR) and its target gene, TRAMP, were expressed in and around the regenerating gut. Pm-RAR-specific and TRAMP-specific double-stranded RNA molecules inhibited the regeneration of the gut, indicating that the RA signal is mediated at least in part by Pm-RAR and TRAMP. These results suggested that RA triggers the transdifferentiation of the atrial epithelium into the gut in regenerating animals, as it does during asexual reproduction.

The in vitro real-time oscillation monitoring system identifies potential entrainment factors for circadian clocks

PubMed Central

Nakahata, Yasukazu; Akashi, Makoto; Trcka, Daniel; Yasuda, Akio; Takumi, Toru

2006-01-01

Background Circadian rhythms are endogenous, self-sustained oscillations with approximately 24-hr rhythmicity that are manifested in various physiological and metabolic processes. The circadian organization of these processes in mammals is governed by the master oscillator within the suprachiasmatic nuclei (SCN) of the hypothalamus. Recent findings revealed that circadian oscillators exist in most organs, tissues, and even in immortalized cells, and that the oscillators in peripheral tissues are likely to be coordinated by SCN, the master oscillator. Some candidates for endogenous entrainment factors have sporadically been reported, however, their details remain mainly obscure. Results We developed the in vitro real-time oscillation monitoring system (IV-ROMS) by measuring the activity of luciferase coupled to the oscillatory gene promoter using photomultiplier tubes and applied this system to screen and identify factors able to influence circadian rhythmicity. Using this IV-ROMS as the primary screening of entrainment factors for circadian clocks, we identified 12 candidates as the potential entrainment factor in a total of 299 peptides and bioactive lipids. Among them, four candidates (endothelin-1, all-trans retinoic acid, 9-cis retinoic acid, and 13-cis retinoic acid) have already been reported as the entrainment factors in vivo and in vitro. We demonstrated that one of the novel candidates, 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2), a natural ligand of the peroxisome proliferator-activated receptor-γ (PPAR-γ), triggers the rhythmic expression of endogenous clock genes in NIH3T3 cells. Furthermore, we showed that 15d-PGJ2 transiently induces Cry1, Cry2, and Rorα mRNA expressions and that 15d-PGJ2-induced entrainment signaling pathway is PPAR-γ – and MAPKs (ERK, JNK, p38MAPK)-independent. Conclusion Here, we identified 15d-PGJ2 as an entrainment factor in vitro. Using our developed IV-ROMS to screen 299 compounds, we found eight novel and four known molecules to be potential entrainment factors for circadian clocks, indicating that this assay system is a powerful and useful tool in initial screenings. PMID:16483373

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) alters the endogenous metabolism of all-trans-retinoic acid in the rat.

PubMed

Schmidt, Carsten K; Hoegberg, Pi; Fletcher, Nicholas; Nilsson, Charlotte B; Trossvik, Christina; Håkansson, Helen; Nau, Heinz

2003-07-01

2,3,7,8-Tetrachlorodibenzo- p-dioxin (TCDD) is known to influence vitamin A homeostasis. In order to investigate the mechanism behind this retinoid disruption, male Sprague-Dawley rats were exposed to TCDD at doses ranging from 0.1 to 100 micro g/kg body weight, and were killed 3 days after exposure. Additional groups of rats were killed 1 and 28 days after a single oral dose of 10 micro g TCDD/kg body weight. Serum, kidney, and liver were investigated for retinoid levels, as well as gene expression and enzyme activities relevant for retinoid metabolism. Besides the well known effects of TCDD on apolar retinoids, i.e. decreased hepatic and increased renal retinyl ester (RE) levels, we have found dose-dependent elevation of all- trans-retinoic acid (all- trans-RA) levels in all investigated tissues. In the liver, 9- cis-4-oxo-13,14-dihydro-RA was drastically decreased by TCDD in a dose-dependent manner. In serum, cis-isomers of all- trans-RA, including 9,13-di- cis-RA, were significantly reduced already at the lowest dose level. Protein and mRNA levels of cellular retinol binding protein I (CRBP-I) in liver or kidneys were not significantly altered by TCDD exposure at doses at which retinoid levels were affected, making CRBP-I an unlikely candidate to account for the alterations in retinoid metabolism caused by TCDD. The expression and activities of relevant cytochrome P450 (CYP) enzymes with potential roles in all- trans-RA synthesis and/or degradation (CYP1A1, 1A2, and 2B1/2) were also monitored. A possible role of CYP1A1 in TCDD-induced all- trans-RA synthesis is suggested from the time-course relationship between CYP1A1 activity and all- trans-RA levels in liver and kidney. The significant alteration of the all- trans-RA metabolism has the potential to contribute significantly to the toxicity of TCDD.

Activation of the dopamine receptor type-2 (DRD2) promoter by 9-cis retinoic acid in a cellular model of Cushing's disease mediates the inhibition of cell proliferation and ACTH secretion without a complete corticotroph-to-melanotroph transdifferentiation.

PubMed

Occhi, Gianluca; Regazzo, Daniela; Albiger, Nora Maria; Ceccato, Filippo; Ferasin, Sergio; Scanarini, Massimo; Denaro, Luca; Cosma, Chiara; Plebani, Mario; Cassarino, Maria Francesca; Mantovani, Giovanna; Stalla, Günter K; Pecori Giraldi, Francesca; Paez-Pareda, Marcelo; Scaroni, Carla

2014-09-01

Cushing's disease (CD) is a rare condition in which hypercortisolemia is secondary to excessive ACTH release from a pituitary corticotroph adenoma. CD is associated with significant morbidity and mortality, and a safe therapy that effectively targets the pituitary tumor is still lacking. Retinoic acid (RA) and dopamine agonists (DAs) have recently been considered as monotherapy in CD patients, and satisfactory results have been reported, albeit in a limited number of patients. Given the permissive role of RA on the dopamine receptor type-2 (DRD2), the aim of the present study was to see whether a combination of 9-cis RA and the DA bromocriptine (Br) might represent a possible treatment for CD. Here we show that 9-cis RA induces a functional DRD2 in the pituitary corticotroph cell line AtT20, and increases cell sensitivity to Br via a mechanism only partially related to corticotroph-to-melanotroph transdifferentiation. In addition, 9-cis RA and Br act synergistically to modulate cell viability, with favorable implications for clinical use. In nearly 45% of corticotropinoma-derived primary cultures, the combined administration of 9-cis RA and Br lowered the steady-state level of the ACTH precursor proopiomelanocortin (POMC) more efficiently than either of the drugs alone. In conclusion, the effects of a combination of 9-cis RA and Br on ACTH synthesis/secretion and cell viability in AtT20, and on POMC transcriptional activity in human corticotropinomas might represent a suitable starting point for assessing the potential of this treatment regimen for ACTH-secreting pituitary adenomas. This study thus has potentially important implications for novel therapeutic approaches to CD.

Retinoic acid postconsolidation therapy for high-risk neuroblastoma patients treated with autologous haematopoietic stem cell transplantation.

PubMed

Peinemann, Frank; van Dalen, Elvira C; Enk, Heike; Berthold, Frank

2017-08-25

Neuroblastoma is a rare malignant disease and mainly affects infants and very young children. The tumours mainly develop in the adrenal medullary tissue, with an abdominal mass as the most common presentation. About 50% of patients have metastatic disease at diagnosis. The high-risk group is characterised by metastasis and other features that increase the risk of an adverse outcome. High-risk patients have a five-year event-free survival of less than 50%. Retinoic acid has been shown to inhibit growth of human neuroblastoma cells and has been considered as a potential candidate for improving the outcome of patients with high-risk neuroblastoma. This review is an update of a previously published Cochrane Review. To evaluate the efficacy and safety of additional retinoic acid as part of a postconsolidation therapy after high-dose chemotherapy (HDCT) followed by autologous haematopoietic stem cell transplantation (HSCT), compared to placebo retinoic acid or to no additional retinoic acid in people with high-risk neuroblastoma (as defined by the International Neuroblastoma Risk Group (INRG) classification system). We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library (2016, Issue 11), MEDLINE in PubMed (1946 to 24 November 2016), and Embase in Ovid (1947 to 24 November 2016). Further searches included trial registries (on 22 December 2016), conference proceedings (on 23 March 2017) and reference lists of recent reviews and relevant studies. We did not apply limits by publication year or languages. Randomised controlled trials (RCTs) evaluating additional retinoic acid after HDCT followed by HSCT for people with high-risk neuroblastoma compared to placebo retinoic acid or to no additional retinoic acid. Primary outcomes were overall survival and treatment-related mortality. Secondary outcomes were progression-free survival, event-free survival, early toxicity, late toxicity, and health-related quality of life. We used standard methodological procedures expected by Cochrane. The update search did not identify any additional studies. We identified one RCT that included people with high-risk neuroblastoma who received HDCT followed by autologous HSCT (N = 98) after a first random allocation and who received retinoic acid (13-cis-retinoic acid; N = 50) or no further therapy (N = 48) after a second random allocation. These 98 participants had no progressive disease after HDCT followed by autologous HSCT. There was no clear evidence of difference between the treatment groups either in overall survival (hazard ratio (HR) 0.87, 95% confidence interval (CI) 0.46 to 1.63; one trial; P = 0.66) or in event-free survival (HR 0.86, 95% CI 0.50 to 1.49; one trial; P = 0.59). We calculated the HR values using the complete follow-up period of the trial. The study also reported overall survival estimates at a fixed point in time. At the time point of five years, the survival estimate was reported to be 59% for the retinoic acid group and 41% for the no-further-therapy group (P value not reported). We did not identify results for treatment-related mortality, progression-free survival, early or late toxicity, or health-related quality of life. We could not rule out the possible presence of selection bias, performance bias, attrition bias, and other bias. We judged the evidence to be of low quality for overall survival and event-free survival, downgraded because of study limitations and imprecision. We identified one RCT that evaluated additional retinoic acid as part of a postconsolidation therapy after HDCT followed by autologous HSCT versus no further therapy in people with high-risk neuroblastoma. There was no clear evidence of a difference in overall survival and event-free survival between the treatment alternatives. This could be the result of low power. Information on other outcomes was not available. This trial was performed in the 1990s, since when many changes in treatment and risk classification have occurred. Based on the currently available evidence, we are therefore uncertain about the effects of retinoic acid in people with high-risk neuroblastoma. More research is needed for a definitive conclusion.

Tretinoin overdose: a first case report.

PubMed

Su-Yin, Adeline; Wong, Joyce; Wiegand, Timothy; Olson, Kent

2009-06-01

Tretinoin (Vesanoid) is an all-trans-retinoic acid, and is related to retinol (Vitamin A). To date, there have been several case reports on overdose with its isomer isotretinoin, but none involving overdose of tretinoin. We report the first known case of a patient who ingested a massive overdose of tretinoin. A 31-year-old man ingested 1000 mg of tretinoin (100 pills of Vesanoid 10 mg) in a suicide attempt. He developed nonbloody diarrhea, but otherwise had no complaints. Clinical examination was normal. The patient was treated with activated charcoal and was hydrated. The patient's blood results did not show any deterioration on the third consecutive day. He was discharged well on the third day, but was subsequently lost to follow-up. Although there has been no reported experience with acute tretinoin overdose in humans, our patient took a dose approximately 3 times the recommended maximum tolerated daily dose in patients with myelodysplastic syndrome or solid tumors (195 mg/m2 per day). Overdose with other retinoids such as isotretinoin have been associated with only minor symptoms that resolved quickly. Our patient had diarrhea, which also resolved quickly with symptomatic treatment and hydration. We believe this to be the first case report of an acute oral overdose of tretinoin. The patient developed diarrhea, but was otherwise asymptomatic.

Efficacy and safety of a 12-month treatment with a combination of hydroxypinacolone retinoate and retinol glycospheres as maintenance therapy in acne patients after oral isotretinoin.

PubMed

Bettoli, Vincenzo; Zauli, Stefania; Borghi, Alessandro; Toni, Giulia; Ricci, Michela; Bertoldi, Alberto M; Virgili, Annarosa

2017-02-01

A correct therapeutic management of acne should include a maintenance therapy to prevent recurrences after discontinuing a successful treatment. The aim of this study is to investigate efficacy and safety of a 12-month maintenance treatment with a product, based on Retinsphere technology that combines retinol encapsulated in glycospheres and hydroxypinacolone retinoate (Biretix gel®), to control acne relapse after a treatment with oral isotretinoin (O.I.). The study consisted of 2 phases: active treatment phase (AP) and maintenance phase (MP). In the AP, 40 consecutive patients with moderate facial acne were treated with O.I. until acne remission. Then, the patients entered in the MP and were treated with Biretix gel® once-daily for 12 months. The efficacy parameter was the relapse rate during MP. Thirty-nine patients completed the study. Relapse appeared in 6 patients (15.38%). The new product with Retinsphere technology was well tolerated and none of the subjects complained of adverse events. Our findings seems to provide favorable evidence of the efficacy and the safety of this new product in the maintenance treatment after O.I. in patient with moderate acne. The efficacy is maintain for a period as long as a year after O.I. suspension.

Crosstalk between ERK2 and RXR regulates nuclear import of transcription factor NGFI-B

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jacobs, Chris M.; Paulsen, Ragnhild E.

2005-10-21

Transcription factor NGFI-B initiates apoptosis when allowed to translocate to mitochondria. Retinoid-X receptor (RXR), another member of the nuclear receptor family, regulates NGFI-B signaling through heterodimerization and nuclear export. Growth factor EGF activates ERK2, which phosphorylates NGFI-B and determines if NGFI-B is allowed to translocate to mitochondria. In the present study, EGF treatment resulted in an increased nuclear import of NGFI-B. Likewise, active ERK2 resulted in a preferential nuclear localization of NGFI-B. When coexpressed with RXR the nuclear import and nuclear localization induced by active ERK2 were strongly reduced. In the presence of its ligand 9-cis-retinoic acid, RXR no longermore » inhibited ERK2-induced nuclear import. Thus, RXR serves a permissive role for ERK2-mediated nuclear accumulation of NGFI-B. This finding represents a novel crosstalk between ERK2 and RXR signaling pathways, and explains how two independent inhibitors of apoptosis (EGF and 9-cis-retinoic acid) may cooperate to regulate nuclear targeting of apoptosis inducer NGFI-B.« less

Proliferative changes in the bronchial epithelium of former smokers treated with retinoids.

PubMed

Hittelman, Walter N; Liu, Diane D; Kurie, Jonathan M; Lotan, Reuben; Lee, Jin Soo; Khuri, Fadlo; Ibarguen, Heladio; Morice, Rodolfo C; Walsh, Garrett; Roth, Jack A; Minna, John; Ro, Jae Y; Broxson, Anita; Hong, Waun Ki; Lee, J Jack

2007-11-07

Retinoids have shown antiproliferative and chemopreventive activity. We analyzed data from a randomized, placebo-controlled chemoprevention trial to determine whether a 3-month treatment with either 9-cis-retinoic acid (RA) or 13-cis-RA and alpha-tocopherol reduced Ki-67, a proliferation biomarker, in the bronchial epithelium. Former smokers (n = 225) were randomly assigned to receive 3 months of daily oral 9-cis-RA (100 mg), 13-cis-RA (1 mg/kg) and alpha-tocopherol (1200 IU), or placebo. Bronchoscopic biopsy specimens obtained before and after treatment were immunohistochemically assessed for changes in the Ki-67 proliferative index (i.e., percentage of cells with Ki-67-positive nuclear staining) in the basal and parabasal layers of the bronchial epithelium. Per-subject and per-biopsy site analyses were conducted. Multicovariable analyses, including a mixed-effects model and a generalized estimating equations model, were used to investigate the treatment effect (Ki-67 labeling index and percentage of bronchial epithelial biopsy sites with a Ki-67 index > or = 5%) with adjustment for multiple covariates, such as smoking history and metaplasia. Coefficient estimates and 95% confidence intervals (CIs) were obtained from the models. All statistical tests were two-sided. In per-subject analyses, Ki-67 labeling in the basal layer was not changed by any treatment; the percentage of subjects with a high Ki-67 labeling in the parabasal layer dropped statistically significantly after treatment with 13-cis-RA and alpha-tocopherol treatment (P = .04) compared with placebo, but the drop was not statistically significant after 9-cis-RA treatment (P = .17). A similar effect was observed in the parabasal layer in a per-site analysis; the percentage of sites with high Ki-67 labeling dropped statistically significantly after 9-cis-RA treatment (coefficient estimate = -0.72, 95% CI = -1.24 to -0.20; P = .007) compared with placebo, and after 13-cis-RA and alpha-tocopherol treatment (coefficient estimate = -0.66, 95% CI = -1.15 to -0.17; P = .008). In per-subject analyses, treatment with 13-cis-RA and alpha-tocopherol, compared with placebo, was statistically significantly associated with reduced bronchial epithelial cell proliferation; treatment with 9-cis-RA was not. In per-site analyses, statistically significant associations were obtained with both treatments.

Proliferative Changes in the Bronchial Epithelium of Former Smokers Treated With Retinoids

PubMed Central

Hittelman, Walter N.; Liu, Diane D.; Kurie, Jonathan M.; Lotan, Reuben; Lee, Jin Soo; Khuri, Fadlo; Ibarguen, Heladio; Morice, Rodolfo C.; Walsh, Garrett; Roth, Jack A.; Minna, John; Ro, Jae Y.; Broxson, Anita; Hong, Waun Ki; Lee, J. Jack

2012-01-01

Background Retinoids have shown antiproliferative and chemopreventive activity. We analyzed data from a randomized, placebo-controlled chemoprevention trial to determine whether a 3-month treatment with either 9-cis-retinoic acid (RA) or 13-cis-RA and α-tocopherol reduced Ki-67, a proliferation biomarker, in the bronchial epithelium. Methods Former smokers (n = 225) were randomly assigned to receive 3 months of daily oral 9-cis-RA (100 mg), 13-cis-RA (1 mg/kg) and α-tocopherol (1200 IU), or placebo. Bronchoscopic biopsy specimens obtained before and after treatment were immunohistochemically assessed for changes in the Ki-67 proliferative index (i.e., percentage of cells with Ki-67–positive nuclear staining) in the basal and parabasal layers of the bronchial epithelium. Per-subject and per–biopsy site analyses were conducted. Multicovariable analyses, including a mixed-effects model and a generalized estimating equations model, were used to investigate the treatment effect (Ki-67 labeling index and percentage of bronchial epithelial biopsy sites with a Ki-67 index ≥ 5%) with adjustment for multiple covariates, such as smoking history and metaplasia. Coefficient estimates and 95% confidence intervals (CIs) were obtained from the models. All statistical tests were two-sided. Results In per-subject analyses, Ki-67 labeling in the basal layer was not changed by any treatment; the percentage of subjects with a high Ki-67 labeling in the parabasal layer dropped statistically significantly after treatment with 13-cis-RA and α-tocopherol treatment (P = .04) compared with placebo, but the drop was not statistically significant after 9-cis-RA treatment (P = .17). A similar effect was observed in the parabasal layer in a per-site analysis; the percentage of sites with high Ki-67 labeling dropped statistically significantly after 9-cis-RA treatment (coefficient estimate = −0.72, 95% CI = −1.24 to −0.20; P = .007) compared with placebo, and after 13-cis-RA and α-tocopherol treatment (coefficient estimate = −0.66, 95% CI = −1.15 to −0.17; P = .008). Conclusions In per-subject analyses, treatment with 13-cis-RA and α-tocopherol, compared with placebo, was statistically significantly associated with reduced bronchial epithelial cell proliferation; treatment with 9-cis-RA was not. In per-site analyses, statistically significant associations were obtained with both treatments. PMID:17971525

Choroidal retinoic acid synthesis: a possible mediator between refractive error and compensatory eye growth.

PubMed

Mertz, J R; Wallman, J

2000-04-01

Research over the past two decades has shown that the growth of young eyes is guided by vision. If near- or far-sightedness is artificially imposed by spectacle lenses, eyes of primates and chicks compensate by changing their rate of elongation, thereby growing back to the pre-lens optical condition. Little is known about what chemical signals might mediate between visual effects on the retina and alterations of eye growth. We present five findings that point to choroidal retinoic acid possibly being such a mediator. First, the chick choroid can convert retinol into all-trans-retinoic acid at the rate of 11 +/- 3 pmoles mg protein(-1) hr(-1), compared to 1.3 +/- 0.3 for retina/RPE and no conversion for sclera. Second, those visual conditions that cause increased rates of ocular elongation (diffusers or negative lens wear) produce a sharp decrease in all-trans-retinoic acid synthesis to levels barely detectable with our assay. In contrast, visual conditions which result in decreased rates of ocular elongation (recovery from diffusers or positive lens wear) produce a four- to five-fold increase in the formation of all-trans-retinoic acid. Third, the choroidal retinoic acid is found bound to a 28-32 kD protein. Fourth, a large fraction of the choroidal retinoic acid synthesized in culture is found in a nucleus-enriched fraction of sclera. Finally, application of retinoic acid to cultured sclera at physiological concentrations produced an inhibition of proteoglycan production (as assessed by measuring sulfate incorporation) with a EC50 of 8 x 10(-7) M. These results show that the synthesis of choroidal retinoic acid is modulated by those visual manipulations that influence ocular elongation and that this retinoic acid may reach the sclera in concentrations adequate to modulate scleral proteoglycan formation.

Mixtures of herbicides and metals affect the redox system of honey bees.

PubMed

Jumarie, Catherine; Aras, Philippe; Boily, Monique

2017-02-01

The increasing loss of bee colonies in many countries has prompted a surge of studies on the factors affecting bee health. In North America, main crops such as maize and soybean are cultivated with extensive use of pesticides that may affect non-target organisms such as bees. Also, biosolids, used as a soil amendment, represent additional sources of metals in agroecosystems; however, there is no information about how these metals could affect the bees. In previous studies we investigated the effects of environmentally relevant doses of herbicides and metals, each individually, on caged honey bees. The present study aimed at investigating the effects of mixtures of herbicides (glyphosate and atrazine) and metals (cadmium and iron), as these mixtures represent more realistic exposure conditions. Levels of metal, vitamin E, carotenoids, retinaldehyde, at-retinol, retinoic acid isomers (9-cis RA, 13-cis RA, at-RA) and the metabolites 13-cis-4-oxo-RA and at-4-oxo-RA were measured in bees fed for 10 days with contaminated syrup. Mixtures of herbicides and cadmium that did not affect bee viability, lowered bee α- and β-carotenoid contents and increased 9-cis-RA as well as 13-cis-4-oxo-RA without modifying the levels of at-retinol. Bee treatment with either glyphosate, a combination of atrazine and cadmium, or mixtures of herbicides promoted lipid peroxidation. Iron was bioconcentrated in bees and led to high levels of lipid peroxidation. Metals also decreased zeaxanthin bee contents. These results show that mixtures of atrazine, glyphosate, cadmium and iron may affect different reactions occurring in the metabolic pathway of vitamin A in the honey bee. Copyright © 2016 Elsevier Ltd. All rights reserved.

Trichoplax adhaerens reveals a network of nuclear receptors sensitive to 9-cis-retinoic acid at the base of metazoan evolution

PubMed Central

Novotný, Jan Philipp; Chughtai, Ahmed Ali; Kostrouchová, Markéta; Kostrouchová, Veronika; Kostrouch, David; Kaššák, Filip; Kaňa, Radek; Schierwater, Bernd; Kostrouchová, Marta

2017-01-01

Trichoplax adhaerens, the only known species of Placozoa is likely to be closely related to an early metazoan that preceded branching of Cnidaria and Bilateria. This animal species is surprisingly well adapted to free life in the World Ocean inhabiting tidal costal zones of oceans and seas with warm to moderate temperatures and shallow waters. The genome of T. adhaerens (sp. Grell) includes four nuclear receptors, namely orthologue of RXR (NR2B), HNF4 (NR2A), COUP-TF (NR2F) and ERR (NR3B) that show a high degree of similarity with human orthologues. In the case of RXR, the sequence identity to human RXR alpha reaches 81% in the DNA binding domain and 70% in the ligand binding domain. We show that T. adhaerens RXR (TaRXR) binds 9-cis retinoic acid (9-cis-RA) with high affinity, as well as high specificity and that exposure of T. adhaerens to 9-cis-RA regulates the expression of the putative T. adhaerens orthologue of vertebrate L-malate-NADP+ oxidoreductase (EC 1.1.1.40) which in vertebrates is regulated by a heterodimer of RXR and thyroid hormone receptor. Treatment by 9-cis-RA alters the relative expression profile of T. adhaerens nuclear receptors, suggesting the existence of natural ligands. Keeping with this, algal food composition has a profound effect on T. adhaerens growth and appearance. We show that nanomolar concentrations of 9-cis-RA interfere with T. adhaerens growth response to specific algal food and causes growth arrest. Our results uncover an endocrine-like network of nuclear receptors sensitive to 9-cis-RA in T. adhaerens and support the existence of a ligand-sensitive network of nuclear receptors at the base of metazoan evolution. PMID:28975052

Cytotoxic effect induced by retinoic acid loaded into galactosyl-sphingosine containing liposomes on human hepatoma cell lines.

PubMed

Díaz, Cecilia; Vargas, Ernesto; Gätjens-Boniche, Omar

2006-11-15

Two retinoids, ATRA and 13cisRA, were incorporated into liposomes of different composition and charge and added to two hepatoma cell lines with different degree of transformation to measure cytotoxicity by MTT assay. Retinoid-free cationic liposomes were more toxic than the other kinds (anionic and made only of PC) but were also the best delivery system for retinoic acid to induce specific cytotoxic effects on these tumor hepatoma cell lines. Galactosyl-sphingosine containing cationic liposomes increased the cytotoxic effect induced by ATRA on Hep3B cells when compared to glucosyl-sphingosine cationic liposomes, but did not improve the effect induced by free retinoid or ATRA loaded into liposomes without glycolipids. This suggests that in this cell line, ATRA is being incorporated by a mechanism mediated by the asialoglycoprotein receptor, but at the same time, non-specific sugar-independent capture is also taking place as well as free diffusion of ATRA directly through the membrane. Galactose-specific effect was not observed in HepG2 cells treated with ATRA or both cell lines treated with 13cisRA. In fact, treatment of HepG2 cells with retinoids entrapped into liposomes likely induces proliferation instead of cytotoxicity, a result that interferes with the measurement of cell death by MTT. Compared to the specific effect of ATRA entrapped into cationic liposomes, vesicles made only by PC, did not mediate a specific mechanism, since differences between ATRA in galactosyl- and glucosyl-shpingosine PC-liposomes were not statistically significant. The specific mechanism was not present in the myoblastic cell line C2C12, where ATRA incorporated into galactosyl- and glucosyl-sphingosine containing cationic and PC-liposomes, was able to induce cytotoxicity at the same extent. Micelles containing ATRA and galactosyl-sphingosine had a significantly more toxic effect than the retinoid administered together with glucosyl-sphingosine, in Hep3B cells. Also, micelles containing ATRA were more toxic than glycolipid-containing liposomes with ATRA, for both kinds of sphingosines. The same effect was not observed in C2C12 cells, where glycolipid-containing liposomes worked better than micelles, and a sugar-specific mechanism was not seen. This suggests that, even though galactose-containing cationic liposomes could be a promising approach, a galactose-specific emulsion system could be the best strategy to specifically deliver retinoic acid to liver tumor cells, since it shows tissue specificity (perhaps induced by ASGPR-mediated internalization) and a stronger cytotoxic effect than the retinoid incorporated into liposomes.

Pharmacokinetics of isotretinoin and its major blood metabolite following a single oral dose to man.

PubMed

Colburn, W A; Vane, F M; Shorter, H J

1983-01-01

A pharmacokinetic profile of isotretinoin and its major dermatologically active blood metabolite, 4-oxo-isotretinoin, was developed following a single 80 mg oral suspension dose of isotretinoin to 15 normal male subjects. Blood samples were assayed for isotretinoin and 4-oxo-isotretinoin using a newly developed reverse-phase HPLC method. Following rapid absorption from the suspension formulation, isotretinoin is distributed and eliminated with harmonic mean half-lives of 1.3 and 17.4 h, respectively. Maximum concentrations of isotretinoin in blood were observed at 1 to 4 h after dosing. Maximum concentrations of the major blood metabolite of isotretinoin, 4-oxo-isotretinoin, are approximately one-half those of isotretinoin and occur at 6 to 16 h after isotretinoin dosing. The ratio of areas under the curve for metabolite and parent drug following the single dose suggests that average steady-state ratios of metabolite to parent drug during a dosing interval will be approximately 2.5. Both isotretinoin and its metabolite can be adequately described using a single linear pharmacokinetic model.

Metabolism of isotretinoin. Biliary excretion of isotretinoin glucuronide in the rat.

PubMed

Meloche, S; Besner, J G

1986-01-01

The biliary metabolites of isotretinoin were examined after iv administration of 4-20-mg/kg doses to vitamin A-normal bile duct-cannulated rats. Analysis of bile by reverse phase high performance liquid chromatography showed that injection of isotretinoin is followed by a rapid excretion of metabolites in bile. Isotretinoin glucuronide was identified as the major metabolite in bile. A specific high performance liquid chromatography method based on the assay of generated isotretinoin in beta-glucuronidase-treated bile was developed for the determination of isotretinoin glucuronide in bile samples. The excretion rate of isotretinoin glucuronide increased rapidly to reach a maximum 55 min after dosing and then declined exponentially. After 330 min of collection, biliary excretion of isotretinoin glucuronide was almost complete, and the metabolite accounted for 34.8-37.9% of the dose. These results indicate that conjugation with glucuronic acid represents a major pathway for the metabolism of pharmacological doses of isotretinoin. The maximum excretion rate of isotretinoin glucuronide in bile increased in a linear manner with the dose of isotretinoin, and no delay was observed after the larger doses. These data suggest that glucuronidation and biliary excretion are not saturated at high pharmacological doses of isotretinoin.

Retinoids induce differentiation and downregulate telomerase activity and N-Myc to increase sensitivity to flavonoids for apoptosis in human malignant neuroblastoma SH-SY5Y cells.

PubMed

Das, Arabinda; Banik, Naren L; Ray, Swapan K

2009-03-01

Human malignant neuroblastoma is characterized by poor differentiation and uncontrolled proliferation of immature neuroblasts. Retinoids such as all-trans-retinoic acid (ATRA), 13-cis-retinoic acid (13-CRA), and N-(4-hydroxyphenyl) retinamide (4-HPR) at low doses are capable of inducing differentiation, while flavonoids such as (-)-epigallocatechin-3-gallate (EGCG) and genistein (GST) at relatively high dose can induce apoptosis. We used combination of retinoid and flavonoid for controlling growth of malignant neuroblastoma SH-SY5Y cells. Cells were treated with a retinoid (1 microM ATRA, 1 microM 13-CRA, or 0.5 microM 4-HPR) for 7 days and then with a flavonoid (25 microM EGCG or 25 microM GST) for 24 h. Treatment of cells with a low dose of a retinoid for 7 days induced neuronal differentiation with downregulation of telomerase activity and N-Myc but overexpression of neurofilament protein (NFP) and subsequent treatment with a relatively high dose of a flavonoid for 24 h increased apoptosis in the differentiated cells. Besides, retinoids reduced the levels of inflammatory and angiogenic factors. Apoptosis was associated with increases in intracellular free [Ca2+], Bax expression, cytochrome c release from mitochondria and activities of calpain and caspases. Decreases in expression of calpastatin (endogenous calpain inhibitor) and baculovirus inhibitor-of-apoptosis repeat containing (BIRC) proteins (endogenous caspase inhibitors) favored apoptosis. Treatment of SH-SY5Y cells with EGCG activated caspase-8, indicating induction of the receptor-mediated pathway of apoptosis. Based on our observation, we conclude that combination of a retinoid and a flavonoid worked synergistically for controlling the malignant growth of human neuroblastoma cells.

Analysis and stability of retinol in plasma.

PubMed

Peng, Y M; Xu, M J; Alberts, D S

1987-01-01

A simple, precise, and specific high-performance liquid chromatography (HPLC) method was developed for the simultaneous measurement of retinol (ROH), 13-cis-retinoic acid (13-cRA), and 4-oxo-13-cRA. The average recovery of ROH from serum or plasma was 95%, and the precision of the assay was less than 5%. With this HPLC method, a series of studies was carried out to evaluate the stability of ROH in various matrices. ROH was stable under our HPLC assay conditions as well as in plasma- and in serum-enriched culture media; however, ROH was not stable in aqueous matrices. Serum or heparinized plasma may be routinely used for measurement of ROH concentrations, providing EDTA, oxalate, and citrate are not used as anticoagulants. Because of ROH stability, blood samples can be kept on ice in the dark for at least 24 hours prior to separation of plasma. In addition, plasma samples containing ROH can be stored for up to 1 year at -20 degrees C without loss of stability.

Concomitant use of isotretinoin and contraceptives before and after iPledge in the United States.

PubMed

Pinheiro, Simone P; Kang, Elizabeth M; Kim, Clara Y; Governale, Laura A; Zhou, Esther H; Hammad, Tarek A

2013-12-01

The major concern associated with isotretinoin treatment is its high teratogenic potential. Therefore, ensuring use of contraception while on therapy is an important strategy for at-risk patients and has been emphasized in all risk management programs. iPledge, the latest and most rigorous isotretinoin program, requires, among other stipulations, monthly assessments of contraceptive use for patients undergoing isotretinoin treatment. The purpose of this study is to evaluate isotretinoin usage patterns and assess concomitant use of isotretinoin and contraceptives before and after iPledge. Female patients aged 13-45 years with a new prescription for isotretinoin products during 2004-2008 were identified in the IMS Health longitudinal prescription claims database. Monthly concomitant use of isotretinoin and contraceptives was estimated. Segmented regression analysis of interrupted time series data was used to assess changes in monthly proportion of concomitant use in the 24 months preceding versus following iPledge implementation. The number of isotretinoin prescriptions decreased after iPledge implementation. A small but significant increase in monthly proportion of patients concomitantly using isotretinoin and contraceptive therapies was observed immediately after iPledge implementation (1.3%, p-value = 0.02), particularly among younger patients (2.5%, p-value < 0.01). No changes in the proportion of concomitancy over time (i.e. slope) between the periods before and after iPledge implementation were observed. The findings of this pharmacy prescription claims-based study suggest a small increase in concomitant use of isotretinoin and contraceptives coincident with the time of implementation of iPledge, particularly among younger women. Published 2013. This article is a U. S. Government work and is in the public domain in the USA. Published 2013. This article is a U. S. Government work and is in the public domain in the USA.

Feasibility of retinoids for the treatment of emphysema study.

PubMed

Roth, Michael D; Connett, John E; D'Armiento, Jeanine M; Foronjy, Robert F; Friedman, Paul J; Goldin, Jonathan G; Louis, Thomas A; Mao, Jenny T; Muindi, Josephia R; O'Connor, George T; Ramsdell, Joe W; Ries, Andrew L; Scharf, Steven M; Schluger, Neil W; Sciurba, Frank C; Skeans, Melissa A; Walter, Robert E; Wendt, Christine H; Wise, Robert A

2006-11-01

Retinoids promote alveolar septation in the developing lung and stimulate alveolar repair in some animal models of emphysema. One hundred forty-eight subjects with moderate-to-severe COPD and a primary component of emphysema, defined by diffusing capacity of the lung for carbon monoxide (Dlco) [37.1 +/- 12.0% of predicted] and CT density mask (38.5 +/- 12.8% of voxels <- 910 Hounsfield units) [mean +/- SD] were enrolled into a randomized, double-blind, feasibility study at five university hospitals. Participants received all-trans retinoic acid (ATRA) at either a low dose (LD) [1 mg/kg/d] or high dose (HD) [2 mg/kg/d], 13-cis retinoic acid (13-cRA) [1 mg/kg/d], or placebo for 6 months followed by a 3-month crossover period. No treatment was associated with an overall improvement in pulmonary function, CT density mask score, or health-related quality of life (QOL) at the end of 6 months. However, time-dependent changes in Dlco (initial decrease with delayed recovery) and St. George Respiratory Questionnaire (delayed improvement) were observed in the HD-ATRA cohort and correlated with plasma drug levels. In addition, 5 of 25 participants in the HD-ATRA group had delayed improvements in their CT scores that also related to ATRA levels. Retinoid-related side effects were common but generally mild. No definitive clinical benefits related to the administration of retinoids were observed in this feasibility study. However, time- and dose-dependent changes in Dlco, CT density mask score, and health-related QOL were observed in subjects treated with ATRA, suggesting the possibility of exposure-related biological activity that warrants further investigation.

Cell-type-specific regulation of the retinoic acid receptor mediated by the orphan nuclear receptor TLX.

PubMed

Kobayashi, M; Yu, R T; Yasuda, K; Umesono, K

2000-12-01

Malformations in the eye can be caused by either an excess or deficiency of retinoids. An early target gene of the retinoid metabolite, retinoic acid (RA), is that encoding one of its own receptors, the retinoic acid receptor beta (RARbeta). To better understand the mechanisms underlying this autologous regulation, we characterized the chick RARbeta2 promoter. The region surrounding the transcription start site of the avian RARbeta2 promoter is over 90% conserved with the corresponding region in mammals and confers strong RA-dependent transactivation in primary cultured embryonic retina cells. This response is selective for RAR but not retinoid X receptor-specific agonists, demonstrating a principal role for RAR(s) in retina cells. Retina cells exhibit a far higher sensitivity to RA than do fibroblasts or osteoblasts, a property we found likely due to expression of the orphan nuclear receptor TLX. Ectopic expression of TLX in fibroblasts resulted in increased sensitivity to RA induction, an effect that is conserved between chick and mammals. We have identified a cis element, the silencing element relieved by TLX (SET), within the RARbeta2 promoter region which confers TLX- and RA-dependent transactivation. These results indicate an important role for TLX in autologous regulation of the RARbeta gene in the eye.

Cell-Type-Specific Regulation of the Retinoic Acid Receptor Mediated by the Orphan Nuclear Receptor TLX†

PubMed Central

Kobayashi, Mime; Yu, Ruth T.; Yasuda, Kunio; Umesono, Kazuhiko

2000-01-01

Malformations in the eye can be caused by either an excess or deficiency of retinoids. An early target gene of the retinoid metabolite, retinoic acid (RA), is that encoding one of its own receptors, the retinoic acid receptor β (RARβ). To better understand the mechanisms underlying this autologous regulation, we characterized the chick RARβ2 promoter. The region surrounding the transcription start site of the avian RARβ2 promoter is over 90% conserved with the corresponding region in mammals and confers strong RA-dependent transactivation in primary cultured embryonic retina cells. This response is selective for RAR but not retinoid X receptor-specific agonists, demonstrating a principal role for RAR(s) in retina cells. Retina cells exhibit a far higher sensitivity to RA than do fibroblasts or osteoblasts, a property we found likely due to expression of the orphan nuclear receptor TLX. Ectopic expression of TLX in fibroblasts resulted in increased sensitivity to RA induction, an effect that is conserved between chick and mammals. We have identified a cis element, the silencing element relieved by TLX (SET), within the RARβ2 promoter region which confers TLX- and RA-dependent transactivation. These results indicate an important role for TLX in autologous regulation of the RARβ gene in the eye. PMID:11073974

Quantification of endogenous retinoic acid in limited biological samples by LC/MS/MS

PubMed Central

Kane, Maureen A.; Chen, Na; Sparks, Susan; Napoli, Joseph L.

2005-01-01

We report a sensitive LC (liquid chromatography)/MS/MS assay using selected reaction monitoring to quantify RA (retinoic acid), which is applicable to biological samples of limited size (10–20 mg of tissue wet weight), requires no sample derivatization, provides mass identification and resolves atRA (all-trans-RA) from its geometric isomers. The assay quantifies over a linear range of 20 fmol to 10 pmol, and has a 10 fmol limit of detection at a signal/noise ratio of 3. Coefficients of variation are: instrumental, 0.5–2.9%; intra-assay, 5.4±0.4%; inter-assay 8.9±1.0%. An internal standard (all-trans-4,4-dimethyl-RA) improves accuracy by confirming extraction efficiency and revealing handling-induced isomerization. Tissues of 2–4-month-old C57BL/6 male mice had atRA concentrations of 7–9.6 pmol/g and serum atRA of 1.9±0.6 pmol/ml (±S.E.M.). Tissue 13-cis-RA ranged from 2.9 to 4.2 pmol/g, and serum 13-cis-RA was 1.2±0.3 pmol/ml. CRBP (cellular retinol-binding protein)-null mouse liver had atRA ∼30% lower than wild-type (P<0.05), but kidney, testis, brain and serum atRA were similar to wild-type. atRA in brain areas of 12-month-old female C57BL/6 mice were (±S.E.M.): whole brain, 5.4±0.4 pmol/g; cerebellum, 10.7±0.3 pmol/g; cortex, 2.6±0.4 pmol/g; hippocampus, 8.4±1.2 pmol/g; striatum, 15.3±4.7 pmol/g. These data provide the first analytically robust quantification of atRA in animal brain and in CRBP-null mice. Direct measurements of endogenous RA should have a substantial impact on investigating target tissues of RA, mechanisms of RA action, and the relationship between RA and chronic disease. PMID:15628969

Retinoid metabolism and transplacental pharmacokinetics in the cynomolgus monkey following a nonteratogenic dosing regimen with all-trans-retinoic acid.

PubMed

Tzimas, G; Nau, H; Hendrickx, A G; Peterson, P E; Hummler, H

1996-11-01

Retinoids often exhibit a complex metabolic pattern and differential transplacental kinetics, which make it difficult to pinpoint the proximate compound responsible for the observed teratogenic effect. We have therefore studied the pharmacokinetics and metabolism of all-trans-retinoic acid (all-trans-RA) in cynomolgus monkeys following application of a nonteratogenic dosing regimen and compared the results with corresponding data from a previous study with a teratogenic dosing regimen with 13-cis-RA [Hummler et al. (1994) Teratology 50:184-193]. All-trans-RA was administered to pregnant cynomolgus monkeys (Macaca fascicularis) by nasogastric intubation at a dose of 5 mg/kg body wt once daily from gestational day (GD) 16 to 26 and twice daily at 8-h intervals from GD 27 to 31. Examination of the fetuses of four dams on GD 100 +/- 2 showed no embryotoxic or teratogenic effects of the applied dosing regimen (Experiment 1). Maternal plasma retinoid pharmacokinetics on GD 16, 26, and 31 as well as embryonic retinoid profiles after the last drug administration on GD 31 were determined in thirteen further dams (Experiment 2). All-trans-RA reached much lower plasma concentrations after the last two treatments on GD 31 than after the first one on GD 16 and the eleventh one on GD 26 (0-24-h area-under-the-concentration-time-curve (AUC) values: 104 +/- 59 ng x h/ml (after the last treatment on GD 31), 189 +/- 110 (GD 16) and 393 +/- 305 ng x h/ml (GD 26). The predominant plasma metabolites of all-trans-RA were its beta-glucuronide and the beta-glucuronide of all-trans-4-oxo-RA. Both of these retinoids accumulated in the plasma during the period of treatment and displayed AUC values 5- to 30-fold higher than those of all-trans-RA. Embryonic concentrations of all-trans-RA were not increased over endogenous levels after the last administration on GD 31 when plasma concentrations were low. To evaluate the placental transport of all-trans-RA in the presence of high plasma concentrations, a further experiment was performed, in which a single dose of all-trans-RA (10 mg/kg body wt) was given to four pregnant monkeys on GD 31, and plasma pharmacokinetics as well as embryonic concentrations of retinoids at 4 h post-treatment were determined (Experiment 3). This dosing schedule yielded high plasma concentrations of all-trans-RA, while embryonic concentrations were about 40% of plasma levels. Based on the plasma AUC values on GDs 16 and 26 obtained in Experiment 2 and the degree of placental transfer, as determined on GD 31 in the presence of high plasma levels in Experiment 3, we estimated embryonic AUC values for the 24-h period following the nonteratogenic doses on GDs 16 and 26 in Experiment 2. These AUC values were similarly high to the embryonic AUC value of all-trans-RA obtained after application of the teratogenic dosing regimen with 13-cis-RA [Hummler et al. (1994) Teratology 50:184-193]. In addition, plasma AUC values of all-trans-RA were 2- to 7-fold higher after all-trans-RA administration (present study) than after dosing with the teratogenic dose of 13-cis-RA. These results strengthen our recent suggestion that the teratogenic effects induced in cynomolgus monkeys by 13-cis-RA treatment cannot solely result from the action of all-trans-RA, but may involve 13-cis-RA and 13-cis-4-oxo-RA, which could act directly or function as transport vehicle.

The Dean and Betty Gallo Prostate Cancer Center

DTIC Science & Technology

2004-07-01

8217 Deleted: Completed 1998), / . Deleted: Clin Cancer Res, 1997 ,phase II study of 13 cis retinoic Completed: Serum TGF- beta and IGF- 30 DiPaola...t , sensitive to activation of both ER alpha and beta . Further laboratory studies by DiPaola and collaborators Deleted: identified additional... Beta -catenin regulates Cripto- and Wnt3- dependent gene expression programs in mouse axis and mesoderm formation. Development, 130: 6283-6294. 2003

Surgical Outcome in Patients Taking Concomitant or Recent Intake of Oral Isotretinoin: A Multicentric Study-ISO-AIMS Study.

PubMed

Mahadevappa, Omprakash Heggadahalli; Mysore, Venkataram; Viswanath, Vishalakshi; Thurakkal, Salim; Majid, Imran; Talwar, Suresh; Aurangabadkar, Sanjeev J; Chatterjee, Manas; Bhat, M Ramesh; Barua, Shyamanta; Ganjoo, Anil

2016-01-01

The current standard recommendation is to avoid surgical interventions in patients taking oral isotretinoin. However, this recommendation has been questioned in several recent publications. To document the safety of cosmetic and surgical interventions, among patients receiving or recently received oral isotretinoin. Association of Cutaneous Surgeons, India, in May 2012, initiated this study, at 11 centers in different parts of India. The data of 183 cases were collected monthly, from June 2012 to May 2013. Of these 61 patients had stopped oral isotretinoin before surgery and 122 were concomitantly taking oral isotretinoin during the study period. In these 183 patients, a total of 504 interventions were performed. These included[1] 246 sessions of chemical peels such as glycolic acid, salicylic acid, trichloroacetic acid, and combination peels;[2] 158 sessions of lasers such as ablative fractional laser resurfacing with erbium-doped yttrium aluminum garnet and CO2, conventional full face CO2 laser resurfacing, laser-assisted hair reduction with long-pulsed neodymium-doped yttrium aluminum garnet, diode laser, and LASIK surgery;[3] 27 sessions of cold steel surgeries such as microneedling, skin biopsy, subcision, punch elevation of scars, excision of skin lesion, and wisdom tooth extraction;[4] 1 session of electrosurgery. No significant side effects were noted in most patients. 2 cases of keloid were documented which amounted to 0.4% of side effects in 504 interventions, with a significant P value of 0.000. Reversible transient side effects were erythema in 10 interventions and hyperpigmentation in 15. The study showed that performing dermatosurgical and laser procedures in patients receiving or recently received isotretinoin is safe, and the current guidelines of avoiding dermatosurgical and laser interventions in such patients taking isotretinoin need to be revised.

Hydroperoxide Lyase and Other Hydroperoxide-Metabolizing Activity in Tissues of Soybean, Glycine max

PubMed Central

Gardner, Harold W.; Weisleder, David; Plattner, Ronald D.

1991-01-01

Hydroperoxide lyase (HPLS) activity in soybean (Glycine max) seed/seedlings, leaves, and chloroplasts of leaves required detergent solubilization for maximum in vitro activity. On a per milligram of protein basis, more HPLS activity was found in leaves, especially chloroplasts, than in seeds or seedlings. The total yield of hexanal from 13(S)-hydroperoxy-cis-9,trans-11-octadecadienoic acid (13S-HPOD) from leaf or chloroplast preparations was 58 and 66 to 85%, respectively. Because of significant competing hydroperoxide-metabolizing activities from other enzymes in seed/seedling preparations, the hexanal yields from this source were lower (36-56%). Some of the products identified from the seed or seedling preparations indicated that the competing activity was mainly due to both a hydroperoxide peroxygenase and reactions catalyzed by lipoxygenase. Different HPLS isozyme compositions in the seed/seedling versus the leaf/chloroplast preparations were indicated by differences in the activity as a function of pH, the Km values, relative Vmax with 13S-HPOD and 13(S)-hydroperoxy-cis-9,trans-11,cis-15-octadecatrienoic acid (13S-HPOT), and the specificity with different substrates. With regard to the latter, both seed/seedling and chloroplast HPLS utilized the 13S-HPOD and 13S-HPOT substrates, but only seeds/seedlings were capable of metabolizing 9(S)-hydroperoxy-trans-10,cis-12-octadecadienoic acid into 9-oxononanoic acid, isomeric nonenals, and 4-hydroxynonenal. From 13S-HPOD and 13S-HPOT, the products were identified as 12-oxo-cis-9-dodecenoic acid, as well as hexanal from 13S-HPOD and cis-3-hexenal from 13S-HPOT. In seed preparations, there was partial isomerization of the cis-3 or cis-9 into trans-2 or trans-10 double bonds, respectively. PMID:16668490

Differential expression of decorin and biglycan genes during palatogenesis in normal and retinoic acid-treated mice.

PubMed

Zhang, Yuxiang; Mori, Tetsuji; Iseki, Ken; Hagino, Seita; Takaki, Hiromi; Takeuchi, Mayumi; Hikake, Tsuyoshi; Tase, Choichiro; Murakawa, Masahiro; Yokoya, Sachihiko; Wanaka, Akio

2003-04-01

Proteoglycans are involved in secondary palate formation. In the present study, we focused on two small leucine-rich proteoglycans, decorin and biglycan, because they assembled extracellular matrix molecules such as collagens and modulated signaling pathway of transforming growth factor-beta. To investigate the functions of decorin and biglycan in palatogenesis, we compared their mRNA expression patterns between normal palate and retinoic acid-induced cleft palate in mice by using in situ hybridization analysis during the period of embryonic day 13.5 (E13.5) to E15.5. On E13.5, decorin mRNA was expressed in the epithelia and mesenchyme on the nasal side of the developing secondary palate. During the period the palate shelves were fusing (E14.5), decorin mRNA was strongly expressed in the mesenchyme but its expression pattern was asymmetric; decorin mRNA expression area in the nasal side was broader than that in the oral side. The expression of decorin mRNA was hardly detected in the mesenchyme on either side of the medial edge epithelium. After fusion (E15.5), its expression converged to the mesenchyme just around the palatine bone. Biglycan mRNA was ubiquitously distributed throughout the palatal mesenchyme for the mid-gestation period. Its expression area became limited to the ossification area within the palate after the late gestation period. In the retinoic acid-treated mice, the area of the decorin gene expression expanded to the core region of the palate primordium where little signal was observed in control mice. On the other hand, biglycan in the retinoic acid-treated mice did not show remarkable change in its distribution patterns compared with that in the control mice. These findings suggest that decorin and biglycan play distinct roles in palatogenesis, and decorin was more actively involved in the process of secondary palate formation than biglycan. Up-regulation of decorin gene expression in the retinoic acid-treated mice might influence the pathogenesis of cleft palate. Copyright 2003 Wiley-Liss, Inc.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colburn, W.A.; Vane, F.M.; Bugge, C.J.

The pharmacokinetics of isotretinoin and 4-oxoisotretinoin in blood, as well as the blood concentrations and urinary, biliary, and fecal excretion of carbon-14 were studied using liquid scintillation counting techniques and reverse phase HPLC methods following a single 80-mg oral suspension dose of UC-isotretinoin to four healthy male subjects and two patients with biliary T-tube drainage. Approximately 80% of the dose was recovered as UC in excreta during the course of the study of which about equal fractions were in the urine and feces. Secondary peaks in blood concentrations of UC were observed in the healthy subjects whereas they were notmore » seen in the patients with T-tubes. The harmonic mean apparent half-life for isotretinoin in the blood of the healthy subjects was 13.6 hr, whereas the corresponding value for the UC was 90 hr. The data for isotretinoin and 4-oxoisotretinoin coupled with the total carbon-14 data suggest that the oral dose of UC-isotretinoin is absorbed to a similar extent by the healthy subjects and T-tube patients, whereas T-tube patients clear the drug more rapidly. The biliary excretion and possible enterohepatic circulation of isotretinoin and its metabolites may have significant impact on the pharmacokinetic profile of isotretinoin in man.« less

Altered sensitivity to ellagic acid in neuroblastoma cells undergoing differentiation with 12-O-tetradecanoylphorbol-13-acetate and all-trans retinoic acid.

PubMed

Alfredsson, Christina Fjæraa; Rendel, Filip; Liang, Qui-Li; Sundström, Birgitta E; Nånberg, Eewa

2015-12-01

Ellagic acid has previously been reported to induce reduced proliferation and activation of apoptosis in several tumor cell lines including our own previous data from non-differentiated human neuroblastoma SH-SY5Y cells. The aim of this study was now to investigate if in vitro differentiation with the phorbol ester 12-O- tetradecanoylphorbol-13-acetate or the vitamin A derivative all-trans retinoic acid altered the sensitivity to ellagic acid in SH-SY5Y cells. The methods used were cell counting and LDH-assay for evaluation of cell number and cell death, flow cytometric analysis of SubG1- and TUNEL-analysis for apoptosis and western blot for expression of apoptosis-associated proteins. In vitro differentiation was shown to reduce the sensitivity to ellagic acid with respect to cell detachment, loss of viability and activation of apoptosis. The protective effect was phenotype-specific and most prominent in all-trans retinoic acid-differentiated cultures. Differentiation-dependent up-regulation of Bcl-2 and integrin expression is introduced as possible protective mechanisms. The presented data also point to a positive correlation between proliferative activity and sensitivity to ellagic-acid-induced cell detachment. In conclusion, the presented data emphasize the need to consider degree of neuronal differentiation and phenotype of neuroblastoma cells when discussing a potential pharmaceutical application of ellagic acid in tumor treatment. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Activation of RAS/ERK alone is insufficient to inhibit RXRα function and deplete retinoic acid in hepatocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Ai-Guo, E-mail: wangaiguotl@hotmail.com; Song, Ya-Nan; Chen, Jun

2014-09-26

Highlights: • The activation of RAS/ERK is insufficient to inhibit RXRα function and deplete RA. • The retinoid metabolism-related genes are down-regulated by ras oncogene. • The atRA has no effect on preventing hepatic tumorigenesis or curing the developed hepatic nodules. - Abstract: Activation of RAS/ERK signaling pathway, depletion of retinoid, and phosphorylation of retinoid X receptor alpha (RXRα) are frequent events found in liver tumors and thought to play important roles in hepatic tumorigenesis. However, the relationships among them still remained to be elucidated. By exploring the transgenic mouse model of hepatic tumorigenesis induced by liver-specific expression of H-ras12Vmore » oncogene, the activation of RAS/ERK, the mRNA expression levels of retinoid metabolism-related genes, the contents of retinoid metabolites, and phosphorylation of RXRα were determined. RAS/ERK signaling pathway was gradually and significantly activated in hepatic tumor adjacent normal liver tissues (P) and hepatic tumor tissues (T) of H-ras12V transgenic mice compared with normal liver tissues (Wt) of wild type mice. On the contrary, the mRNA expression levels of retinoid metabolism-related genes were significantly reduced in P and T compared with Wt. Interestingly, the retinoid metabolites 9-cis-retinoic acid (9cRA) and all-trans-retinoic acid (atRA), the well known ligands for nuclear transcription factor RXR and retinoic acid receptor (RAR), were significantly decreased only in T compared with Wt and P, although the oxidized polar metabolite of atRA, 4-keto-all-trans-retinoic-acid (4-keto-RA) was significantly decreased in both P and T compared with Wt. To our surprise, the functions of RXRα were significantly blocked only in T compared with Wt and P. Namely, the total protein levels of RXRα were significantly reduced and the phosphorylation levels of RXRα were significantly increased only in T compared with Wt and P. Treatment of H-ras12V transgenic mice at 5-week-old or 5-month-old with atRA had no effect on the prevention of tumorigenesis or cure of developed nodules in liver. These events imply that the depletion of 9cRA and atRA and the inhibition of RXRα function in hepatic tumors involve more complex mechanisms besides the activation of RAS/ERK pathway.« less

Radiolabeling and initial biological evaluation of [18F]KBM-1 for imaging RAR-α receptors in neuroblastoma.

PubMed

Solingapuram Sai, Kiran Kumar; Das, Bhaskar C; Sattiraju, Anirudh; Almaguel, Frankis G; Craft, Suzanne; Mintz, Akiva

2017-03-15

Retinoic acid receptor alpha (RAR-α) plays a significant role in a number of diseases, including neuroblastoma. Children diagnosed with high-risk neuroblastoma are treated13-cis-retinoic acid, which reduces risk of cancer recurrence. Neuroblastoma cell death is mediated via RAR-α, and expression of RAR-α is upregulated after treatment. A molecular imaging probe that binds RAR-α will help clinicians to diagnose and stratify risk for patients with neuroblastoma, who could benefit from retinoid-based therapy. In this study, we report the radiolabeling, and initial in vivo evaluation of [ 18 F]KBM-1, a novel RAR-α agonist. The radiochemical synthesis of [ 18 F]KBM-1 was carried out through KHF 2 assisted substitution of [ 18 F] - from aryl-substituted pinacolatoesters-based retinoid precursor. In vitro cell uptake assay in human neuroblastoma cell line showed that the uptake of [ 18 F]KBM-1 was significantly inhibited by all three blocking agents (KBM-1, ATRA, BD4) at all the selected incubation times. Standard biodistribution in mice bearing neuroblastoma tumors demonstrated increased tumor uptake from 5min to 60min post radiotracer injection and the uptake ratios for target to non-target (tumor: muscle) increased 2.2-fold to 3.7-fold from 30min to 60min post injection. Tumor uptake in subset of 30min blocking group was 1.7-fold lower than unblocked. These results demonstrate the potential utility of [ 18 F]KBM-1 as a RAR-α imaging agent. Copyright © 2017 Elsevier Ltd. All rights reserved.

Retinoic acid-induced CHD5 upregulation and neuronal differentiation of neuroblastoma.

PubMed

Higashi, Mayumi; Kolla, Venkatadri; Iyer, Radhika; Naraparaju, Koumudi; Zhuang, Tiangang; Kolla, Sriharsha; Brodeur, Garrett M

2015-08-07

Chromodomain-helicase DNA binding protein 5 (CHD5) is an important tumor suppressor gene deleted from 1p36.31 in neuroblastomas (NBs). High CHD5 expression is associated with a favorable prognosis, but deletion or low expression is frequent in high-risk tumors. We explored the role of CHD5 expression in the neuronal differentiation of NB cell lines. NB cell lines SH-SY5Y (SY5Y), NGP, SK-N-DZ, IMR5, LAN5, SK-N-FI, NB69 and SH-EP were treated with 1-10 μM 13-cis-retinoic acid (13cRA) for 3-12 days. qRT-PCR and Western blot analyses were performed to measure mRNA and protein expression levels, respectively. Morphological differences were examined by both phase contrast and immunofluorescence studies. Treatment of SY5Y cells with 13cRA caused upregulation of CHD5 expression in a time- and dose-dependent manner (1, 5, or 10 μM for 7 or 12 days) and also induced neuronal differentiation. Furthermore, both NGP and SK-N-DZ cells showed CHD5 upregulation and neuronal differentiation after 13cRA treatment. In contrast, 13cRA treatment of IMR5, LAN5, or SK-N-FI induced neither CHD5 expression nor neuronal differentiation. NB69 cells showed two different morphologies (neuronal and substrate adherent) after 12 days treatment with 10 μM of 13cRA. CHD5 expression was high in the neuronal cells, but low/absent in the flat, substrate adherent cells. Finally, NGF treatment caused upregulation of CHD5 expression and neuronal differentiation in SY5Y cells transfected to express TrkA (SY5Y-TrkA) but not in TrkA-null parental SY5Y cells, and both changes were blocked by a pan-TRK inhibitor. Treatment with 13cRA induces neuronal differentiation only in NB cells that upregulate CHD5. In addition, NGF induced CHD5 upregulation and neuronal differentiation only in TrkA expressing cells. Together, these results suggest that CHD5 is downstream of TrkA, and CHD5 expression may be crucial for neuronal differentiation induced by either 13cRA or TrkA/NGF signaling.

Estrogen-dependent downregulation of hairy and enhancer of split homolog-1 gene expression in breast cancer cells is mediated via a 3' distal element.

PubMed

Müller, Patrick; Merrell, Kenneth W; Crofts, Justin D; Rönnlund, Caroline; Lin, Chin-Yo; Gustafsson, Jan-Ake; Ström, Anders

2009-03-01

Regulation of hairy and enhancer of split homologue-1 (HES-1) by estradiol and all-trans retinoic acid affects proliferation of human breast cancer cells. Here, we identify and characterize cis-regulatory elements involved in HES-1 regulation. In the distal 5' promoter of the HES-1 gene, we found a retinoic acid response element and in the distal 3' region, an estrogen receptor alpha(ER)alpha binding site. The ERalpha binding site, composed of an estrogen response element (ERE) and an ERE half-site, is important for both ERalpha binding and transcriptional regulation. Chromatin immunoprecipitation assays revealed that ERalpha is recruited to the ERE and associates with the HES-1 promoter. We also show recruitment of nuclear receptor co-regulators to the ERE in response to estradiol, followed by a decrease in histone acetylation and RNA polymerase II docking in the HES-1 promoter region. Our findings are consistent with a novel type of repressive estrogen response element in the distal 3' region of the HES-1 gene.

Retinoic acid downregulates Rae1 leading to APC(Cdh1) activation and neuroblastoma SH-SY5Y differentiation.

PubMed

Cuende, J; Moreno, S; Bolaños, J P; Almeida, A

2008-05-22

In neuroblastoma cells, retinoic acid induces cell cycle arrest and differentiation through degradation of the F-box protein, Skp2, and stabilization of cyclin-dependent kinase inhibitor, p27. However, the mechanism responsible for retinoic acid-mediated Skp2 destabilization is unknown. Since Skp2 is degraded by anaphase-promoting complex (APC)(Cdh1), here we studied whether retinoic acid promotes differentiation of human SH-SY5Y neuroblastoma cells by modulating Cdh1. We found that retinoic acid induced the nuclear accumulation of Cdh1 that paralleled Skp2 destabilization and p27 accumulation. The mRNA and protein abundance of Rae1-a nuclear export factor that limits APC(Cdh1) activity in mitosis-decreased upon retinoic acid-induced inhibition of neuroblastoma cell proliferation. Furthermore, either Rae1 overexpression or Cdh1 inhibition promoted Skp2 accumulation, p27 destabilization and prevented retinoic acid-induced cell cycle arrest and differentiation. Conversely, inhibition of Rae1 accelerated retinoic acid-induced differentiation. Thus, retinoic acid downregulates Rae1, hence facilitating APC(Cdh1)-mediated Skp2 degradation leading to the arrest of cell cycle progression and neuroblastoma differentiation.

Therans-3-enoic acids ofAster alpinus andArctium minus seed oils.

PubMed

Morris, L J; Marshall, M O; Hammond, E W

1968-01-01

Thetrans-3-enoic acids ofAster alpinus (dwarf aster, rock aster) andArctium minus (burdock) seed oils have been isolated and characterized.Arctium seed oil containstrans-3,cis-9,cis-12-octadecatrienoic acid (9.9%), andAster oil containstrans-3-hexadecenoic (7.1%),rans-3-octadecenoic (1.9%),trans-3,cis-9-octadecadienoic (3.0%),a ndtrans-3,cis-9,cis-12-octadecatrienoic (13.7%) acids.Aster oil also has an epoxy acid as a minor constituent (ca. 2.0%), which has been identified ascis-9,10-epoxy-cis-12-octadecenoic acid.

Metabolism of Linoleic Acid by Barley Lipoxygenase and Hydroperoxide Isomerase 1

PubMed Central

Lulai, Edward C.; Baker, Charles W.; Zimmerman, Don C.

1981-01-01

The oxidation of linoleic acid in incubation mixtures containing extracts of barley lipoxygenase and hydroperoxide isomerase, and the production of these enzymes in quiescent and germinated barley, were investigated. The ratio of 9-hydroperoxylinoleic acid to 13-hydroperoxylinoleic acid was higher for incubation mixtures containing extracts of quiescent barley than for mixtures containing extracts of germinated barley; production of 13-hydroperoxylinoleic acid from germinated barley exceeded that of quiescent barley. Hydroperoxy metabolites of linoleic acid were converted to 9-hydroxy-10-oxo-cis-12-octadecenoic acid, 13-hydroxy-10-oxo-trans-11-octadecenoic acid, and small amounts of 11-hydroxy-12,13-epoxy-cis-9-octadecenoic acid and 11-hydroxy-9,10-epoxy-cis-13-octadecenoic acid whether quiescent or germinated barley was the enzyme source; a fifth product, 13-hydroxy-12-oxo-cis-9-octadecenoic acid was formed only when germinated barley was the enzyme source. Lipoxygenase was readily extracted by buffer, but hydroperoxide isomerase was bound in a catalytically active state to the insoluble barley grist and was efficiently extracted only when Triton X-100 was included in the extraction buffer. Hydroperoxide isomerase was localized in the embryo of quiescent barley, but it was present in the embryo, acrospire, and in small but concentrated amounts in the rootlet of germinating barley. The levels of both lipoxygenase and hydroperoxide isomerase increased through the thirteenth day of germination. Images PMID:16662032

Imposex induction is mediated through the Retinoid X Receptor signalling pathway in the neogastropod Nucella lapillus.

PubMed

Castro, L Filipe C; Lima, D; Machado, A; Melo, C; Hiromori, Y; Nishikawa, J; Nakanishi, T; Reis-Henriques, M A; Santos, M M

2007-11-15

The imposex phenomenon in female prosobranch gastropods provides one of the best documented examples of endocrine disruption in wildlife. While many field studies have demonstrated the negative impact of tributyltin (TBT) upon female gastropods, the mechanism(s) underlying imposex development has not yet been fully clarified. Over the years several hypotheses have been raised to determine the biochemical and molecular determinants of this process. Nevertheless, the interplay between the different suggested pathways (neuroendocrine, steroid and retinoid) is still unknown. Hence, through a combination of exposure experiments, we show that the 9-cis-retinoic acid (9cisRA), the proposed natural ligand of the retinoic X receptor (RXR), induces imposex in females of Nucella lapillus to the same degree as tributyltin, when administered at similar concentrations (1 microg/g body weight). Methoprene acid, a selective ligand for RXR, also induces imposex, albeit to a lower degree than that of the positive control. In contrast, testosterone significantly induced imposex, but had no effect on female penis induction, while the neuropeptide APGWamide had no effect on imposex development. These results clearly demonstrate that imposex induction in N. lapillus is mediated through the modulation of the RXR signalling pathways. In addition to the effects reported in female dogwhelks, both TBT and RA significantly increased male penis length, thus suggesting that TBT may also impact male secondary sex organs through the RXR signalling pathways. As a step for future studies, we have cloned the orthologue of N. lapillus RXR and provide experimental evidence that it binds 9cisRA. Finally, the basal expression level of RXR in several tissues of N. lapillus was determined through real-time PCR, thus showing that RXR is ubiquitously expressed in mollusc tissues, with the highest expression levels being recorded in female and male gonads. The mechanistic impacts of the overall findings to the imposex process are discussed.

Biohydrogenation of C20 polyunsaturated fatty acids by anaerobic bacteria.

PubMed

Sakurama, Haruko; Kishino, Shigenobu; Mihara, Kousuke; Ando, Akinori; Kita, Keiko; Takahashi, Satomi; Shimizu, Sakayu; Ogawa, Jun

2014-09-01

The PUFAs include many bioactive lipids. The microbial metabolism of C18 PUFAs is known to produce their bioactive isomers, such as conjugated FAs and hydroxy FAs, but there is little information on that of C20 PUFAs. In this study, we aimed to obtain anaerobic bacteria with the ability to produce novel PUFAs from C20 PUFAs. Through the screening of ∼100 strains of anaerobic bacteria, Clostridium bifermentans JCM 1386 was selected as a strain with the ability to saturate PUFAs during anaerobic cultivation. This strain converted arachidonic acid (cis-5,cis-8,cis-11,cis-14-eicosatetraenoic acid) and EPA (cis-5,cis-8,cis-11,cis-14,cis-17-EPA) into cis-5,cis-8,trans-13-eicosatrienoic acid and cis-5,cis-8,trans-13,cis-17-eicosatetraenoic acid, giving yields of 57% and 67% against the added PUFAs, respectively. This is the first report of the isolation of a bacterium transforming C20 PUFAs into corresponding non-methylene-interrupted FAs. We further investigated the substrate specificity of the biohydrogenation by this strain and revealed that it can convert two cis double bonds at the ω6 and ω9 positions in various C18 and C20 PUFAs into a trans double bond at the ω7 position. This study should serve to open up the development of novel potentially bioactive PUFAs. Copyright © 2014 by the American Society for Biochemistry and Molecular Biology, Inc.

HISTOPATHOLOGICAL ANALYSIS OF THE F344 RAT LUNG UPON EXPOSURE TO RETENOIC ACID, OVALBUMIN, MOLD SPORES AND CITRAL.

PubMed

Farah, Ibrahim O; Holt-Gray, Carlene; Cameron, Joseph A; Tucci, Michelle; Benghuzzi, Hamed

2017-01-01

The paradoxical role of retinoic acid (All Trans Retinoic Acid; ATRA) in the development of allergic and/or inflammatory complications in contrast to a therapeutic modality for lung pathology is not well understood or established in the literature. As well, the role of Citral (inhibitor of retinoid function; a non-toxic chemical that exists in two forms (diethyl; C1 or cis-trans dimethyl; C2), in the reversal of retinoic acid, ovalbumin and allergic mold spore pathophysiology is also not well ascertained under an in vivo setting. Therefore, it is hypothesized that exposure of F344 lung tissues to supra-physiologic levels of retinoic acid, ovalbumin and mold spores individually or in combination with each other will lead to inflammatory tissue pathology and that Citral 1 and 2 will reverse or ameliorate the related pathological damage to lung tissues. Even though ovalbumin and retinoic acid have been previously applied through intra-tracheal route in cancer prevention and immunological research, the objective of this study was to evaluate the histopathological implications of such exposure in vivo. This IACUC approved in vivo study used Fischer 344 rats ( n = 80 ; 229 to 273g), which were randomly assigned to controls as well as ovalbumin and mold-sensitized treatment groups (0.80 mg/kg and 1×10 9 mold spores combined from 4 strains/100 μl intra-tracheal; all others were dosed by intra-peritoneal injection at days 1 and 7 with 80 mg/kg each of ATRA as well as 20 and 50 mg/kg each of Citrals 1 or 2 individually or in combination to represent all four chemicals and mold spores treatments. Positive and negative controls for each treatment were also included in the study. Animals were housed in rat cages at the JSU Research Animal Core Facilities and were placed on a 12:12 light-dark cycle. A standard rodent diet and water access were provided ad libidum. All animals were sacrificed on day 21 and lung tissues were processed for histopathology. Slides were prepared and were digitized for comparison of tissues pathology. Results showed that exposure of the F344 rats to ovalbumin and ATRA showed various levels of lung tissue damage that was ameliorated by Citral 2 in combination. Mold and ATRA exposure caused various levels of lung tissue damage that was reversed by C1 in combination with each other. Taken together, the study showed that there are variable pathologic inflammatory responses from the interaction of ovalbumin, Citrals, mold spores and retinoic acid, and that the addition of Citrals have reversed lung tissue pathologies. These findings warrants further investigation as to the actual role of these interactions in relation to acute/chronic lung disease and the possibility of reversing retinoid-mediated pathologies in the Fisher rat model.

Evaluation of retinoic acid ophthalmic emulsion in dry eye.

PubMed

Selek, H; Unlü, N; Orhan, M; Irkeç, M

2000-01-01

An oil in water emulsion of 0.01% all-trans-retinoic acid (tretinoin) was prepared and clinically evaluated in dry eye patients. The ophthalmic emulsion consisted of 10% of arachis oil and 90% of the hydrogel of Carbopol 940. To evaluate retinoic acid emulsion clinically, a placebo-controlled, open-labeled, randomized study was performed with 22 dry-eye patients. Symptoms were recorded before and after the treatments. The Schirmer I test, measurement of tear film break-up time (BUT), rose Bengal and fluorescein staining of cornea and conjunctiva, and mucus fern test were done. Retinoic acid did not improve the dryness, photophobia and foreign body sensation more than placebo. Schirmer test and BUT were significantly improved by retinoic acid treatment. Corneal and conjunctival epithelium maintained their characteristics during the use of retinoic acid, as indicated by rose Bengal and fluorescein staining. Ophthalmic emulsion of retinoic acid can be suggested as a promising approach for the treatment of dry eye.

IMPACT OF ATRA ON OVALBUMIN AND MOLD-SENSITIZED F344 RATS AND REVERSAL OF HEALTH-RELATED IMPLICATIONS BY CITRAL.

PubMed

Farah, Ibrahim O; Holt-Gray, Carlene; Cameron, Joseph A; Tucci, Michelle; Benghuzzi, Hamed

2017-01-01

The role of retinoic acid (All Trans Retinoic Acid; ATRA) in the development of hypervitaminosis A pathophysiology is not well understood or established in the literature. As well, the role of Citral (inhibitor of retinoid function; a non-toxic chemical that exists in two forms (diethyl; C1 or cis-trans dimethyl; C2).) in the reversal of pathophysiological implications is also not ascertained under an in vivo setting. Therefore, it is hypothesized that ovalbumin exposure will sensitize the body to supra-physiologic levels of retinoic acid leading to a negative pathophysiological impact and that Citrals 1 and 2 will reverse or ameliorate the related damage to the body's pathophysiology. Even though ovalbumin and retinoic have been previously applied through intra-tracheal route in cancer prevention and immunological research, the objective of this study was to evaluate their interaction as a remedy for hypervitaminosis A. This IACUC approved in vivo study used Fischer 344 rats ( n = 80 ;229 to 273g), which were randomly assigned to controls as well as ovalbumin and mold-sensitized treatment groups (0.80 mg/kg and 1X109 mold spores combined from 4 strains/100 μl intra-tracheal; all others were dosed by intra-peritoneal injection at days 1 and 7 with 80 mg/kg each of ATRA as well as 20 and 50 mg/kg each of Citrals 1 or 2 individually or in combination to represent all four chemicals and mold spores treatments.. Positive and negative controls for each treatment were also included in the study. Animals were housed in rat cages at the JSU Research Animal Core Facilities and were placed on a 12:12 light dark cycle. A standard rodent diet and water access were provided ad-libidum. Rat weights were recorded on day 1 and 21, all animals were sacrificed on day 21 and blood was collected and processed for hematological parameters. Results showed that even though C1 and C2 were not toxic individually, their combination at high dosing was lethal. Exposure of ovalbumin-sensitized rats to ATRA showed various levels of weight losses and negative hematological implications that were ameliorated by exposure to Citrals at various combinations with retinoic acid. Taken together, the study showed that there are variable pathophysiological responses from the interaction of ovalbumin, mold spores and retinoic acid and that Citrals were found to be individually effective in reversing health-related pathophysiologies. These findings warrants further investigations as to the actual role of these interactions in relation to acute pathophysiologic health implications and the possibility of reversing hypervitaminosis A-mediated health-related impacts.

Pharmacokinetics of 14C-isotretinoin in healthy volunteers and volunteers with biliary T-tube drainage.

PubMed

Colburn, W A; Vane, F M; Bugge, C J; Carter, D E; Bressler, R; Ehmann, C W

1985-01-01

The pharmacokinetics of isotretinoin and 4-oxoisotretinoin in blood, as well as the blood concentrations and urinary, biliary, and fecal excretion of carbon-14 were studied using liquid scintillation counting techniques and reverse phase HPLC methods following a single 80-mg oral suspension dose of 14C-isotretinoin to four healthy male subjects and two patients with biliary T-tube drainage. Approximately 80% of the dose was recovered as 14C in excreta during the course of the study of which about equal fractions were in the urine and feces. Secondary peaks in blood concentrations of 14C were observed in the healthy subjects whereas they were not seen in the patients with T-tubes. The harmonic mean apparent half-life for isotretinoin in the blood of the healthy subjects was 13.6 hr, whereas the corresponding value for the 14C was 90 hr. Although a rigorous comparison of pharmacokinetic parameters between healthy subjects and T-tube patients was not feasible due to the limited number of subjects studied, comparisons of certain trends in the pharmacokinetic profiles gave some possible insights into the role of biliary excretion and enterohepatic cycling on the disposition of isotretinoin. The data for isotretinoin and 4-oxoisotretinoin coupled with the total carbon-14 data suggest that the oral dose of 14C-isotretinoin is absorbed to a similar extent by the healthy subjects and T-tube patients, whereas T-tube patients clear the drug more rapidly. The biliary excretion and possible enterohepatic circulation of isotretinoin and its metabolites may have significant impact on the pharmacokinetic profile of isotretinoin in man.

All-trans retinoic acid inhibits craniopharyngioma cell growth: study on an explant cell model.

PubMed

Li, Qiang; You, Chao; Zhou, Liangxue; Sima, Xiutian; Liu, Zhiyong; Liu, Hao; Xu, Jianguo

2013-05-01

The ratio between FABP5 and CRABPII determines cellular response to physiological level of retinoic acid; tumor cells undergo proliferation with high level of FABP5 and apoptosis with high level of CRABPII. We intended to study FABP5 and CRABPII expression in craniopharyngiomas, to establish craniopharyngioma cell model using explants method, and to study the effect of pharmacological dose of retinoic acid on craniopharyngioma cells. Expression of FABP5 and CRABPII in craniopharyngioma tissue from 20 patients was studied using immunohistochemistry. Primary craniopharyngioma cell cultures were established using tissue explants method. Craniopharyngioma cells were treated using various concentrations of all-trans retinoic acid, and cell growth curve, apoptosis, expression of FABP5, CRABPII and NF-κB were assayed in different groups. FABP5/CRABPII ratio was significantly higher in adamatinomatous group than that in papillary group. Cell cultures were established in 19 cases (95 %). Pharmacological level retinoic acid inhibited cell growth and induced cellular apoptosis in dose dependent manner, and apoptosis rate cells treated with 30 μM retinoic acid for 24 h was 43 %. Also, retinoic acid increased CRABPII, and decreased FABP5 and NF-κB expression in craniopharyngioma cells. High FABP5/CRABPII ratio is observed in adamatinomatous craniopharyngioma. Retinoic acid at pharmacological level induced craniopharyngioma cell apoptosis via increasing FABP5/CRABPII ratio and inhibiting NF-κB signaling pathway. Our study demonstrated that all-trans retinoic acid might be a candidate for craniopharyngioma adjuvant chemotherapy in future.

Retinoic acid stimulation of human dermal fibroblast proliferation is dependent on suboptimal extracellular Ca2+ concentration.

PubMed Central

Varani, J.; Shayevitz, J.; Perry, D.; Mitra, R. S.; Nickoloff, B. J.; Voorhees, J. J.

1990-01-01

Human dermal fibroblasts failed to proliferate when cultured in medium containing 0.15 mmol/l (millimolar) Ca2+ (keratinocyte growth medium [KGM]) but did when the external Ca2+ concentration was raised to 1.4 mmol/l. All-trans retinoic acid (retinoic acid) stimulated proliferation in KGM but did not further stimulate growth in Ca2(+)-supplemented KGM. The ability of retinoic acid to stimulate proliferation was inhibited in KGM prepared without Ca2+ or prepared with 0.03 mmol/l Ca2+ and in KGM treated with 1 mmol/l ethylene-glycol-bis-(beta-aminoethyl ether)N,N'-tetra acetic acid. Using 45Ca2+ to measure Ca2+ influx and efflux, it was found that retinoic acid minimally increased Ca2+ uptake into fibroblasts. In contrast, retinoic acid treatment of fibroblasts that had been pre-equilibrated for 1 day with 45Ca2+ inhibited release of intracellular Ca2+ into the extracellular fluid. Retinoic acid also stimulated 35S-methionine incorporation into trichloroacetic acid-precipitable material but in contrast to its effect on proliferation, stimulation of 35S-methionine incorporation occurred in both high-Ca2+ and low-Ca2+ medium. These data indicate that retinoic acid stimulation of proliferation, but not protein synthesis, is dependent on the concentration of Ca2+ in the extracellular environment. PMID:2356860

Isotretinoin therapy changes the expression of antimicrobial peptides in acne vulgaris.

PubMed

Borovaya, Alena; Dombrowski, Yvonne; Zwicker, Stephanie; Olisova, Olga; Ruzicka, Thomas; Wolf, Ronald; Schauber, Jürgen; Sárdy, Miklós

2014-10-01

In acne vulgaris, antimicrobial peptides (AMPs) could play a dual role; i.e., protective by acting against Propionibacterium acnes, pro-inflammatory by acting as signalling molecules. The cutaneous expression of 15 different AMPs was investigated in acne patients; furthermore, the impact of isotretinoin therapy on AMP expression was analysed in skin biopsies from 13 patients with acne vulgaris taken before, during and after a 6-month treatment cycle with isotretinoin using quantitative real-time polymerase chain reaction. Cutaneous expression of the AMPs cathelicidin, human β-defensin-2 (HBD-2), lactoferrin, lysozyme, psoriasin (S100A7), koebnerisin (S100A15), and RNase 7 was upregulated in untreated acne vulgaris, whereas α-defensin-1 (HNP-1) was downregulated compared to controls. While relative expression levels of cathelicidin, HBD-2, lactoferrin, psoriasin (S100A7), and koebnerisin (S100A15) decreased during isotretinoin treatment, only those of cathelicidin and koebnerisin returned to normal after 6 months of isotretinoin therapy. The increased expression of lysozyme and RNase 7 remained unaffected by isotretinoin treatment. The levels of granulysin, RANTES (CCL5), perforin, CXCL9, substance P, chromogranin B, and dermcidin were not regulated in untreated acne patients and isotretinoin had no effect on these AMPs. In conclusion, the expression of various AMPs is altered in acne vulgaris. Isotretinoin therapy normalizes the cutaneous production of distinct AMPs while the expression of others is still increased in healing acne. Considering the antimicrobial and pro-inflammatory role of AMPs, these molecules could serve as specific targets for acne therapy and maintenance of clinical remission.

Regulation of fish growth hormone transcription.

PubMed

Farchi-Pisanty, O; Hackett, P B; Moav, B

1995-09-01

Regulation of endogenous fish growth hormone transcription was studied using carp pituitaries in vitro. It was demonstrated that thyroid hormone (T3) and 9-cis retinoic acid have increased the steady state levels of growth hormone messenger RNA in pituitary cells, as compared with beta-actin messenger RNA levels. In contrast, estrogen failed to increase growth hormone mRNA levels. The possible involvement of thyroid hormone receptor in pituitary gene expression was demonstrated by in situ localization of both growth hormone mRNA and thyroid hormone receptor mRNA in the pituitaries as early as 4 days after fertilization.

Terminal-group oxidation of retinol by mouse epidermis. Inhibition in vitro and in vivo.

PubMed Central

Connor, M J; Smit, M H

1987-01-01

Locally applied retinol is metabolized to retinoic acid in mouse epidermis in vivo. To characterize the oxidation system we investigated the ability of soluble extracts of hairless-mouse epidermis to convert retinol and retinal into retinoic acid. The extracts oxidized retinol to retinoic acid in two steps catalysed by two NAD+-dependent enzymes that were resolved on h.p.l.c. The first enzyme catalyses the reversible oxidation of retinol to retinal and is an alcohol dehydrogenase isoenzyme. The second enzyme oxidizes retinal to retinoic acid. Retinol oxidation by epidermal extracts was inhibited by the alcohol dehydrogenase inhibitor 4-methylpyrazole and by the polyene citral. The toxicity and relatively low potency at inhibiting the epidermal alcohol dehydrogenase isoenzyme curtailed the use of 4-methylpyrazole in vivo. However, citral significantly inhibited retinoic acid formation from retinol in the epidermis in vivo. The ability to inhibit the oxidation of retinol to retinoic acid in mouse epidermis provides a potential method to resolve the roles of retinol and retinoic acid in epithelial function. PMID:3663136

Retinoic acid as a novel medical therapy for Cushing's disease in dogs.

PubMed

Castillo, Victor; Giacomini, Damiana; Páez-Pereda, Marcelo; Stalla, Johanna; Labeur, Marta; Theodoropoulou, Marily; Holsboer, Florian; Grossman, Ashley B; Stalla, Günter K; Arzt, Eduardo

2006-09-01

Cushing's disease is almost always caused by an ACTH-secreting pituitary tumor, but effective medical therapy is currently limited. Because retinoic acid has been shown to be potentially useful in decreasing corticotroph secretion and proliferation in rodent models, we have studied its action in dogs with Cushing's disease. A randomized treatment with retinoic acid (n = 22) vs. ketoconazole (n = 20) in dogs with Cushing's disease was assigned for a period of 180 d. Clinical signs, plasma ACTH and alpha-MSH, the cortisol/creatinine urine ratio, and pituitary magnetic resonance imaging were assessed and compared at different time points. We recorded a significant reduction in plasma ACTH and alpha-MSH, and also in the cortisol/creatinine urine ratio, of the dogs treated with retinoic acid. Pituitary adenoma size was also significantly reduced at the end of retinoic acid treatment. Survival time and all the clinical signs evaluated showed an improvement in the retinoic-acid-treated dogs. No adverse events or signs of hepatotoxicity were observed, suggesting that the drug is not only effective but also safe. Retinoic acid treatment controls ACTH and cortisol hyperactivity and tumor size in dogs with ACTH-secreting tumors, leading to resolution of the clinical phenotype. This study highlights the possibility of using retinoic acid as a novel therapy in the treatment of ACTH-secreting tumors in humans with Cushing's disease.

Metabolism of α-linolenic acid during incubations with strained bovine rumen contents: products and mechanisms.

PubMed

Honkanen, Anne M; Leskinen, Heidi; Toivonen, Vesa; McKain, Nest; Wallace, R John; Shingfield, Kevin J

2016-06-01

Description of α-linolenic acid (cis-9,cis-12,cis-15-18 : 3, ALA) metabolism in the rumen is incomplete. Ruminal digesta samples were incubated with ALA and buffer containing water or deuterium oxide to investigate the products and mechanisms of ALA biohydrogenation. Geometric Δ9,11,15-18 : 3 isomers were the main intermediates formed from ALA. An increase in the n+1 isotopomers of Δ9,11,15-18 : 3 was due to 2H labelling at C-13. Isomers of Δ9,11,13-18 : 3, cis-7,cis-12,cis-15-18 : 3 and cis-8,cis-12,cis-15-18 : 3 were also formed. No increase in n+1 isotopomers of Δ7,12,15-18 : 3 or Δ8,12,15-18 : 3 was detected. Enrichment in n+2 isotopomers of 18 : 2 products indicated that ALA metabolism continued via the reduction of 18 : 3 intermediates. Isomers of Δ9,11,15-18 : 3 were reduced to Δ11,15-18 : 2 labelled at C-9 and C-13. ALA resulted in the formation of Δ11,13-18 : 2 and Δ12,14-18 : 2 containing multiple 2H labels. Enrichment of the n+3 isotopomer of Δ12,15-18 : 2 was also detected. Metabolism of ALA during incubations with rumen contents occurs by one of three distinct pathways. Formation of Δ9,11,15-18 : 3 appears to be initiated by H abstraction on C-13. Octadecatrienoic intermediates containing cis-12 and cis-15 double bonds are formed without an apparent H exchange with water. Labelling of Δ9,11,13-18 : 3 was inconclusive, suggesting formation by an alternative mechanism. These findings explain the appearance of several bioactive fatty acids in muscle and milk that influence the nutritional value of ruminant-derived foods.

Enzymology of retinoic acid biosynthesis and degradation

PubMed Central

Kedishvili, Natalia Y.

2013-01-01

All-trans-retinoic acid is a biologically active derivative of vitamin A that regulates numerous physiological processes. The concentration of retinoic acid in the cells is tightly regulated, but the exact mechanisms responsible for this regulation are not completely understood, largely because the enzymes involved in the biosynthesis of retinoic acid have not been fully defined. Recent studies using in vitro and in vivo models suggest that several members of the short-chain dehydrogenase/reductase superfamily of proteins are essential for retinoic acid biosynthesis and the maintenance of retinoic acid homeostasis. However, the exact roles of some of these recently identified enzymes are yet to be characterized. The properties of the known contributors to retinoid metabolism have now been better defined and allow for more detailed understanding of their interactions with retinoid-binding proteins and other retinoid enzymes. At the same time, further studies are needed to clarify the interactions between the cytoplasmic and membrane-bound proteins involved in the processing of hydrophobic retinoid metabolites. This review summarizes current knowledge about the roles of various biosynthetic and catabolic enzymes in the regulation of retinoic acid homeostasis and outlines the remaining questions in the field. PMID:23630397

Eradication of acute promyelocytic leukemia-initiating cells through PML-RARA degradation.

PubMed

Nasr, Rihab; Guillemin, Marie-Claude; Ferhi, Omar; Soilihi, Hassan; Peres, Laurent; Berthier, Caroline; Rousselot, Philippe; Robledo-Sarmiento, Macarena; Lallemand-Breitenbach, Valérie; Gourmel, Bernard; Vitoux, Dominique; Pandolfi, Pier Paolo; Rochette-Egly, Cécile; Zhu, Jun; de Thé, Hugues

2008-12-01

Retinoic acid and arsenic trioxide target the protein stability and transcriptional repression activity of the fusion oncoprotein PML-RARA, resulting in regression of acute promyelocytic leukemia (APL). Phenotypically, retinoic acid induces differentiation of APL cells. Here we show that retinoic acid also triggers growth arrest of leukemia-initiating cells (LICs) ex vivo and their clearance in PML-RARA mouse APL in vivo. Retinoic acid treatment of mouse APLs expressing the fusion protein PLZF-RARA triggers full differentiation, but not LIC loss or disease remission, establishing that differentiation and LIC loss can be uncoupled. Although retinoic acid and arsenic synergize to clear LICs through cooperative PML-RARA degradation, this combination does not enhance differentiation. A cyclic AMP (cAMP)-dependent phosphorylation site in PML-RARA is crucial for retinoic acid-induced PML-RARA degradation and LIC clearance. Moreover, activation of cAMP signaling enhances LIC loss by retinoic acid, identifying cAMP as another potential APL therapy. Thus, whereas transcriptional activation of PML-RARA is likely to control differentiation, its catabolism triggers LIC eradication and long-term remission of mouse APL. Therapy-triggered degradation of oncoproteins could be a general strategy to eradicate cancer stem cells.

9-Cis retinoic acid protects against methamphetamine-induced neurotoxicity in nigrostriatal dopamine neurons.

PubMed

Reiner, David J; Yu, Seong-Jin; Shen, Hui; He, Yi; Bae, Eunkyung; Wang, Yun

2014-04-01

Methamphetamine (MA) is a drug of abuse as well as a dopaminergic neurotoxin. 9-Cis retinoic acid (9cRA), a biologically active derivative of vitamin A, has protective effects against damage caused by H(2)O(2) and oxygen-glucose deprivation in vitro as well as infarction and terminal deoxynucleotidyl transferase-mediated dNTP nick-end labeling (TUNEL) labeling in ischemic brain. The purpose of this study was to examine if there was a protective role for 9cRA against MA toxicity in nigrostriatal dopaminergic neurons. Primary dopaminergic neurons, prepared from rat embryonic ventral mesencephalic tissue, were treated with MA. High doses of MA decreased tyrosine hydroxylase (TH) immunoreactivity while increasing TUNEL labeling. These toxicities were significantly reduced by 9cRA. 9cRA also inhibited the export of Nur77 from nucleus to cytosol, a response that activates apoptosis. The interaction of 9cRA and MA in vivo was next examined in adult rats. 9cRA was delivered intracerebroventricularly; MA was given (5 mg/kg, 4×) one day later. Locomotor behavior was measured 2 days after surgery for a period of 48 h. High doses of MA significantly reduced locomotor activity and TH immunoreactivity in striatum. Administration of 9cRA antagonized these changes. Previous studies have shown that 9cRA can induce bone morphogenetic protein-7 (BMP7) expression and that administration of BMP7 attenuates MA toxicity. We demonstrated that MA treatment significantly reduced BMP7 mRNA expression in nigra. Noggin (a BMP antagonist) antagonized 9cRA-induced behavioral recovery and 9cRA-induced normalization of striatal TH levels. Our data suggest that 9cRA has a protective effect against MA-mediated neurodegeneration in dopaminergic neurons via upregulation of BMP.

9-cis retinoic acid protects against methamphetamine-induced neurotoxicity in nigrostriatal dopamine neurons

PubMed Central

Reiner, David J; Yu, Seong-Jin; Shen, Hui; He, Yi; Bae, Eunkyung; Wang, Yun

2013-01-01

Methamphetamine (MA) is a drug of abuse as well as a dopaminergic neurotoxin. 9-cis retinoic acid (9cRA), a biologically active derivative of vitamin A, has protective effects against damage caused by H2O2 and oxygen-glucose deprivation in vitro as well as infarction and TUNEL labeling in ischemic brain. The purpose of this study was to examine if there was a protective role for 9cRA against MA toxicity in nigrostriatal dopaminergic neurons. Primary dopaminergic neurons, prepared from rat embryonic ventral mesencephalic tissue, were treated with MA. High doses of MA decreased tyrosine hydroxylase (TH) immunoreactivity while increasing TUNEL labeling. These toxicities were significantly reduced by 9cRA. 9cRA also inhibited the export of Nur77 from nucleus to cytosol, a response that activates apoptosis. The interaction of 9cRA and MA in vivo was next examined in adult rats. 9cRA was delivered intracerebroventricularly; MA was given (5 mg/kg, 4x) one day later. Locomotor behavior was measured two days after surgery for a period of 48 hours. High doses of MA significantly reduced locomotor activity and TH immunoreactivity in striatum. Administration of 9cRA antagonized these changes. Previous studies have shown that 9cRA can induce bone morphogenetic protein-7 (BMP7) expression and that administration of BMP7 attenuates MA toxicity. We demonstrated that MA treatment significantly reduced BMP7 mRNA expression in nigra. Noggin (a BMP antagonist) antagonized 9cRA-induced behavioral recovery and 9cRA-induced normalization of striatal TH levels. Our data suggest that 9cRA has a protective effect against MA -mediated neurodegeneration in dopaminergic neurons via upregulation of BMP. PMID:23884514

REACTIVITY PROFILE OF LIGANDS OF MAMMALIAN RETINOIC ACID RECEPTORS: A PRELIMINARY COREPA ANALYSIS

EPA Science Inventory

Retinoic acid and associated derivatives comprise a class of endogenous hormones that bind to and activate different families of retinoic acid receptors (RARs, RXRs), and control many aspects of vertebrate development. Identification of potential RAR and RXR ligands is of interes...

Both retinoic-acid-receptor- and retinoid-X-receptor-dependent signalling pathways mediate the induction of the brown-adipose-tissue-uncoupling-protein-1 gene by retinoids.

PubMed Central

Alvarez, R; Checa, M; Brun, S; Viñas, O; Mampel, T; Iglesias, R; Giralt, M; Villarroya, F

2000-01-01

The intracellular pathways and receptors mediating the effects of retinoic acid (RA) on the brown-fat-uncoupling-protein-1 gene (ucp-1) have been analysed. RA activates transcription of ucp-1 and the RA receptor (RAR) is known to be involved in this effect. However, co-transfection of an expression vector for retinoid-X receptor (RXR) increases the action of 9-cis RA but not the effects of all-trans RA on the ucp-1 promoter in brown adipocytes. Either RAR-specific ¿p-[(E)-2-(5,6,7,8,-tetrahydro-5,5,8, 8-tetramethyl-2-naphthalenyl)-1-propenyl]benzoic acid¿ or RXR-specific [isopropyl-(E,E)-(R,S)-11-methoxy-3,7, 11-trimethyldodeca-2,4-dienoate, or methoprene] synthetic compounds increase the expression of UCP-1 mRNA and the activity of chloramphenicol acetyltransferase expression vectors driven by the ucp-1 promoter. The RXR-mediated action of 9-cis RA requires the upstream enhancer region at -2469/-2318 in ucp-1. During brown-adipocyte differentiation RXRalpha and RXRgamma mRNA expression is induced in parallel with UCP-1 mRNA, whereas the mRNA for the three RAR subtypes, alpha, beta and gamma, decreases. Co-transfection of murine expression vectors for the different RAR and RXR subtypes indicates that RARalpha and RARbeta as well as RXRalpha are the major retinoid-receptor subtypes capable of mediating the responsiveness of ucp-1 to retinoids. It is concluded that the effects of retinoids on ucp-1 transcription involve both RAR- and RXR-dependent signalling pathways. The responsiveness of brown adipose tissue to retinoids in vivo relies on a complex combination of the capacity of RAR and RXR subtypes to mediate ucp-1 induction and their distinct expression in the differentiated brown adipocyte. PMID:10600643

Three Conazoles Increase Hepatic Microsomal Retinoic Acid Metabolism and Decrease Mouse Hepatic Retinoic Acid Levels In Vivo

EPA Science Inventory

Conazoles are fungicides used in agriculture and as pharmaceuticals. In a previous toxicogenomic study of triazole-containing conazoles we found gene expression changes consistent with the alteration of the metabolism of all trans-retinoic acid (atRA), a vitamin A metabolite with...

Nutrigenomic regulation of adipose tissue development --- role of retinoic acid: A review

PubMed Central

Wang, Bo; Yang, Qiyuan; Harris, Corrine L.; Nelson, Mark L.; Busboom, Jan R.; Zhu, Mei-Jun; Du, Min

2016-01-01

To improve the efficiency of animal production, livestock have been extensively selected or managed to reduce fat accumulation and increase lean growth, which reduces intramuscular or marbling fat content. To enhance marbling, a better understanding of the mechanisms regulating adipogenesis is needed. Vitamin A has recently been shown to have a profound impact on all stages of adipogenesis. Retinoic acid, an active metabolite of vitamin A, activates both retinoic acid receptors (RAR) and retinoid X receptors (RXR), inducing epigenetic changes in key regulatory genes governing adipogenesis. Additionally, Vitamin D and folates interact with the retinoic acid receptors to regulate adipogenesis. In this review, we discuss nutritional regulation of adipogenesis, focusing on retinoic acid and its impact on epigenetic modifications of key adipogenic genes. PMID:27086067

Adenovirus E1A functions as a cofactor for retinoic acid receptor beta (RAR beta) through direct interaction with RAR beta.

PubMed

Folkers, G E; van der Saag, P T

1995-11-01

Transcription regulation by DNA-bound activators is thought to be mediated by a direct interaction between these proteins and TATA-binding protein (TBP), TFIIB, or TBP-associated factors, although occasionally cofactors or adapters are required. For ligand-induced activation by the retinoic acid receptor-retinoid X receptor (RAR-RXR) heterodimer, the RAR beta 2 promoter is dependent on the presence of E1A or E1A-like activity, since this promoter is activated by retinoic acid only in cells expressing such proteins. The mechanism underlying this E1A requirement is largely unknown. We now show that direct interaction between RAR and E1A is a requirement for retinoic acid-induced RAR beta 2 activation. The activity of the hormone-dependent activation function 2 (AF-2) of RAR beta is upregulated by E1A, and an interaction between this region and E1A was observed, but not with AF-1 or AF-2 of RXR alpha. This interaction is dependent on conserved region III (CRIII), the 13S mRNA-specific region of E1A. Deletion analysis within this region indicated that the complete CRIII is needed for activation. The putative zinc finger region is crucial, probably as a consequence of interaction with TBP. Furthermore, the region surrounding amino acid 178, partially overlapping with the TBP binding region, is involved in both binding to and activation by AF-2. We propose that E1A functions as a cofactor by interacting with both TBP and RAR, thereby stabilizing the preinitiation complex.

Effects of Tributyltin and Other Retinoid Receptor Agonists in Reproductive-Related Endpoints in the Zebrafish (Danio rerio).

PubMed

Lima, Daniela; Castro, L Filipe C; Coelho, Inês; Lacerda, Ricardo; Gesto, Manuel; Soares, Joana; André, Ana; Capela, Ricardo; Torres, Tiago; Carvalho, António Paulo; Santos, Miguel M

2015-01-01

Both field and experimental data examined the influence of exposure to environmental contaminant tributyltin (TBT) on marine organisms. Although most attention focused on the imposex phenomenon in gastropods, adverse effects were also observed in other taxonomic groups. It has been shown that imposex induction involves modulation of retinoid signaling in gastropods. Whether TBT influences similar pathways in fish is yet to be addressed. In this study, larvae of the model teleost Danio rerio were exposed to natural retinoids, all-trans-retinoic acid, 9-cis-retinoic acid, and all-trans-retinol, as well as to the RXR synthetic pan-agonist methoprene acid (MA) and to TBT. Larvae were exposed to TBT from 5 days post fertilization (dpf) to adulthood, and reproductive capacity was assessed and correlated with mode of action. TBT significantly decreased fecundity at environmentally relevant levels at 1 μg TBT Sn/g in diet. Interestingly, in contrast to previous reports, TBT altered zebrafish sex ratio toward females, whereas MA exposure biased sex toward males. Since fecundity was significantly altered in the TBT-exposed group with up to 62% decrease, the potentially affected pathways were investigated. Significant downregulation was observed in brain mRNA levels of aromatase b (CYP19a1b) in females and peroxisome proliferator activated receptor gamma (PPARg) in both males and females, suggesting an involvement of these pathways in reproductive impairment associated with TBT.

Light-Activated Reversible Imine Isomerization: Towards a Photochromic Protein Switch.

PubMed

Berbasova, Tetyana; Santos, Elizabeth M; Nosrati, Meisam; Vasileiou, Chrysoula; Geiger, James H; Borhan, Babak

2016-03-02

Mutants of cellular retinoic acid-binding protein II (CRABPII), engineered to bind all-trans-retinal as an iminium species, demonstrate photochromism upon irradiation with light at different wavelengths. UV light irradiation populates the cis-imine geometry, which has a high pKa , leading to protonation of the imine and subsequent "turn-on" of color. Yellow light irradiation yields the trans-imine isomer, which has a depressed pKa , leading to loss of color because the imine is not protonated. The protein-bound retinylidene chromophore undergoes photoinduced reversible interconversion between the colored and uncolored species, with excellent fatigue resistance. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

History of retinoic acid receptors.

PubMed

Benbrook, Doris M; Chambon, Pierre; Rochette-Egly, Cécile; Asson-Batres, Mary Ann

2014-01-01

The discovery of retinoic acid receptors arose from research into how vitamins are essential for life. Early studies indicated that Vitamin A was metabolized into an active factor, retinoic acid (RA), which regulates RNA and protein expression in cells. Each step forward in our understanding of retinoic acid in human health was accomplished by the development and application of new technologies. Development cDNA cloning techniques and discovery of nuclear receptors for steroid hormones provided the basis for identification of two classes of retinoic acid receptors, RARs and RXRs, each of which has three isoforms, α, β and ɣ. DNA manipulation and crystallographic studies revealed that the receptors contain discrete functional domains responsible for binding to DNA, ligands and cofactors. Ligand binding was shown to induce conformational changes in the receptors that cause release of corepressors and recruitment of coactivators to create functional complexes that are bound to consensus promoter DNA sequences called retinoic acid response elements (RAREs) and that cause opening of chromatin and transcription of adjacent genes. Homologous recombination technology allowed the development of mice lacking expression of retinoic acid receptors, individually or in various combinations, which demonstrated that the receptors exhibit vital, but redundant, functions in fetal development and in vision, reproduction, and other functions required for maintenance of adult life. More recent advancements in sequencing and proteomic technologies reveal the complexity of retinoic acid receptor involvement in cellular function through regulation of gene expression and kinase activity. Future directions will require systems biology approaches to decipher how these integrated networks affect human stem cells, health, and disease.

Fundamental studies of adrenal retinoid-X-receptor: Protein isoform, tissue expression, subcellular distribution, and ligand availability.

PubMed

Cheng, Behling; Al-Shammari, Fatema H; Ghader, Isra'a A; Sequeira, Fatima; Thakkar, Jitendra; Mathew, Thazhumpal C

2017-07-01

Adrenal gland reportedly expresses many nuclear receptors that are known to heterodimerize with retinoid-X-receptor (RXR) for functions, but the information regarding the glandular RXR is not adequate. Studies of rat adrenal homogenate by Western blotting revealed three RXR proteins: RXRα (55kDa), RXRβ (47kDa) and RXR (56kDa). RXRγ was not detectable. After fractionation, RXRα was almost exclusively localized in the nuclear fraction. In comparison, substantial portions of RXRβ and RXR were found in both nuclear and post-nuclear particle fractions, suggesting genomic and non-genomic functions. Cells immunostained for RXRα were primarily localized in zona fasciculata (ZF) and medulla, although some stained cells were found in zona glomerulosa (ZG) and zona reticularis (ZR). In contrast, cells immunostained for RXRβ were concentrated principally in ZG, although some stained cells were seen in ZR, ZF, and medulla (in descending order, qualitatively). Analysis of adrenal lipid extracts by LC/MS did not detect 9-cis-retinoic acid (a potent RXR-ligand) but identified all-trans retinoic acid. Since C20 and C22 polyunsaturated fatty acids (PUFAs) can also activate RXR, subcellular availabilities of unesterified fatty acids were investigated by GC/MS. As results, arachidonic acid (C20:4), adrenic acid (C22:4), docosapentaenoic acid (C22:5), and cervonic acid (C22:6) were detected in the lipids extracted from each subcellular fraction. Thus, the RXR-agonizing PUFAs are available in all the main subcellular compartments considerably. The present findings not only shed light on the adrenal network of RXRs but also provide baseline information for further investigations of RXR heterodimers in the regulation of adrenal steroidogenesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Chemoprevention of hormone-dependent prostate cancer in the Wistar-Unilever rat.

PubMed

McCormick, D L; Rao, K V

1999-01-01

The high incidence and long latent period of prostate cancer make it an ideal target for chemoprevention. We have evaluated a series of agents for chemopreventive efficacy using a model in which hormone-dependent prostate cancers are induced in the Wistar-Unilever (WU) rat by sequential treatment with antiandrogen (cyproterone acetate), androgen (testosterone propionate), and direct-acting chemical carcinogen (N-methyl-N-nitrosourea), followed by chronic androgen stimulation (testosterone). This regimen reproducibly induces prostate cancers in high incidence, with no gross toxicity and a low incidence of neoplasia in the seminal vesicle and other non-target tissues. Dehydroepiandrosterone (DHEA) and 9-cis-retinoic acid (9-cis-RA) are the most active agents identified to date. DHEA inhibits prostate cancer induction both when chronic administration is begun prior to carcinogen exposure, and when administration is delayed until preneoplastic prostate lesions are present. 9-cis-RA is the most potent inhibitor of prostate carcinogenesis identified; a study to determine the efficacy of delayed administration of 9-cis-RA is in progress. Liarozole fumarate confers modest protection against prostate carcinogenesis, while N-(4-hydroxyphenyl)retinamide (fenretinide), alpha-difluoromethylornithine, oltipraz, DL-alpha-tocopherol acetate (vitamin E), and L-selenomethionine are inactive. Chemoprevention efficacy evaluations in the WU rat will support the identification of agents that merit study for prostate cancer chemoprevention in humans.

[13C]-Specific labeling of 8-2' linked (-)-cis-blechnic, (-)-trans-blechnic and (-)-brainic acids in the fern Blechnum spicant

NASA Technical Reports Server (NTRS)

Davin, Laurence B.; Wang, Chang-Zeng; Helms, Gregory L.; Lewis, Norman G.

2003-01-01

In vivo administration experiments using stable (13C) and radio (14C) labeled precursors established that the optically active 8-2' linked lignans, (-)-cis-blechnic, (-)-trans-blechnic and (-)-trans-brainic acids, were directly derived from L-phenylalanine, cinnamate, and p-coumarate but not either from tyrosine or acetate. The radiochemical time course data suggest that the initial coupling product is (-)-cis-blechnic acid, which is then apparently converted into both (-)-trans-blechnic and (-)-trans-brainic acids in vivo. These findings provide additional evidence for vascular plant proteins engendering distinct but specific phenolic radical-radical coupling modes, i.e., for full control over phenylpropanoid coupling in vivo, whether stereoselective or regiospecific.

New approaches to male non-hormonal contraception

PubMed Central

Nya-Ngatchou, Jean-Jacques; Amory, John K.

2012-01-01

A non-hormonal male contraceptive is a contraceptive that does not involve the administration of hormones or hormone blockers. This review will focus on the use of lonidamine derivatives and inhibitors of retinoic acid biosynthesis and function as approaches to male non-hormonal contraception. Two current lonidamine derivatives, Adjudin and H2-gamendazole, are in development as male contraceptives. These potent anti-spermatogenic compounds impair the integrity of the apical ectoplasmic specialization, resulting in premature spermiation and infertility. Another approach to male contraceptive development is the inhibition of retinoic acid in the testes, as retinoic acid signaling is necessary for spermatogenesis. The administration of the retinoic acid receptor antagonist BMS-189453 reversibly inhibits spermatogenesis in mice. Similarly, oral dosing of WIN 18,446, which inhibits testicular retinoic acid biosynthesis, effectively contracepts rabbits. Hopefully, one of these approaches to non-hormonal male contraception will prove to be safe and effective in future clinical trials. PMID:22995542

Treatment of mild to moderate acne with a fixed combination of hydroxypinacolone retinoate, retinol glycospheres and papain glycospheres.

PubMed

Veraldi, S; Barbareschi, M; Guanziroli, E; Bettoli, V; Minghetti, S; Capitanio, B; Sinagra, J L; Sedona, P; Schianchi, R

2015-04-01

A fixed combination of 0.1% hydroxypinacolone retinoate (synthetic esther of 9-cis-retinoic acid), 1% retinol in glycospheres and 2% papain in glycospheres in aqueous gel has been recently introduced into the Italian market in order to reduce the incidence and severity of irritant contact dermatitis caused by topical retinoids, without compromising their efficacy. Primary objectives of this sponsor-free, pilot, open, multicenter study were to evaluate the efficacy and tolerability of this gel in patients with comedonal-papular, mild to moderate acne of the face. Ninety-eight Caucasian patients (28 males and 70 females), with an age ranging from 15 to 40 years, were treated with the gel once daily for 12 weeks. Acne severity and treatment efficacy were evaluated by means of the Global Acne Grading System (GAGS) and lesions count. Ninety-four patients were considered evaluable. A 41% mean reduction in the GAGS score was observed; a 40.8% mean reduction of total lesions was recorded; 15.3% of patients experienced mild to moderate local side effects (dryness, peeling, erythema, burning). No patients stopped the treatment because of these side effects. This study, based on a high number of evaluable patients, demonstrates that this fixed combination is an effective and safe option for the treatment of comedonal-papular, mild to moderate acne of the face. A controlled clinical study is necessary to confirm these data.

Bexarotene via CBP/p300 induces suppression of NF-κB-dependent cell growth and invasion in thyroid cancer.

PubMed

Cras, Audrey; Politis, Béatrice; Balitrand, Nicole; Darsin-Bettinger, Diane; Boelle, Pierre Yves; Cassinat, Bruno; Toubert, Marie-Elisabeth; Chomienne, Christine

2012-01-15

Retinoic acid (RA) treatment has been used for redifferentiation of metastatic thyroid cancer with loss of radioiodine uptake. The aim of this study was to improve the understanding of RA resistance and investigate the role of bexarotene in thyroid cancer cells. A model of thyroid cancer cell lines with differential response to RA was used to evaluate the biological effects of retinoid and rexinoid and to correlate this with RA receptor levels. Subsequently, thyroid cancer patients were treated with 13-cis RA and bexarotene and response evaluated on radioiodine uptake reinduction on posttherapy scan and conventional imaging. In thyroid cancer patients, 13-cis RA resistance can be bypassed in some tumors by bexarotene. A decreased tumor growth without differentiation was observed confirming our in vitro data. Indeed, we show that ligands of RARs or RXRs exert different effects in thyroid cancer cell lines through either differentiation or inhibition of cell growth and invasion. These effects are associated with restoration of RARβ and RXRγ levels and downregulation of NF-κB targets genes. We show that bexarotene inhibits the transactivation potential of NF-κB in an RXR-dependent manner through decreased promoter permissiveness without interfering with NF-κB nuclear translocation and binding to its responsive elements. Inhibition of transcription results from the release of p300 coactivator from NF-κB target gene promoters and subsequent histone deacetylation. This study highlights dual mechanisms by which retinoids and rexinoids may target cell tumorigenicity, not only via RARs and RXRs, as expected, but also via NF-κB pathway. ©2011 AACR.

The efficacy of 5% dapsone gel plus oral isotretinoin versus oral isotretinoin alone in acne vulgaris: A randomized double-blind study

PubMed Central

Faghihi, Gita; Rakhshanpour, Mehrdad; Abtahi-Naeini, Bahareh; Nilforoushzadeh, Mohammad Ali

2014-01-01

Background: Acne vulgaris, a common human skin condition, is an inflammatory disease characterized by comedones, papules, nodules and possibly scarring. This study aimed to evaluate the efficacy of a combination of 5% dapsone gel plus oral isotretinoin in the treatment of acne vulgaris. Materials and Methods: A randomized, placebo-controlled, study was carried out on patients with moderate to severe acne. The patients were randomly divided in two groups: (dapsone gel and vehicle gel). All Patients were administered oral isotretinoin 20 mg daily and topical gel twice a day for 8 weeks. The Global Acne Assessment Score (GAAS), the number lesions and side-effects were documented at base line and weeks 4, 8 and 12. Results: A total of 58 patients (age range: 18-25 years) were included in our study. The number of lesions was significantly lower in the dapsone-treated group at all follow-up visits (P < 0.001). The mean GAAS score in the dapsone-treated group and in the Placebo-treated group decreased, but there was no statistical difference in two groups (P < 0.001). The side-effects on the dapsone-treated group were a mild burning sensation in 7 patients (24.13%), mild erythema of the skin and mild dryness in 4 (13.79%) and 3 (10.34%) cases respectively (P < 0.001). In our study, adverse effects were common but they were minor and tolerable. No clinically significant changes in laboratory parameters were observed (P < 0.001). Conclusions: Dapsone gel was an effective medication for patients who received isotretinoin for acne vulgaris treatment resulting in a significant reduction of the number of lesions. PMID:25250291

Proteinuria Impairs Podocyte Regeneration by Sequestering Retinoic Acid

PubMed Central

Peired, Anna; Angelotti, Maria Lucia; Ronconi, Elisa; la Marca, Giancarlo; Mazzinghi, Benedetta; Sisti, Alessandro; Lombardi, Duccio; Giocaliere, Elisa; Della Bona, Marialuisa; Villanelli, Fabio; Parente, Eliana; Ballerini, Lara; Sagrinati, Costanza; Wanner, Nicola; Huber, Tobias B.; Liapis, Helen; Lazzeri, Elena; Lasagni, Laura

2013-01-01

In CKD, the risk of kidney failure and death depends on the severity of proteinuria, which correlates with the extent of podocyte loss and glomerular scarring. We investigated whether proteinuria contributes directly to progressive glomerulosclerosis through the suppression of podocyte regeneration and found that individual components of proteinuria exert distinct effects on renal progenitor survival and differentiation toward a podocyte lineage. In particular, albumin prevented podocyte differentiation from human renal progenitors in vitro by sequestering retinoic acid, thus impairing retinoic acid response element (RARE)-mediated transcription of podocyte-specific genes. In mice with Adriamycin nephropathy, a model of human FSGS, blocking endogenous retinoic acid synthesis increased proteinuria and exacerbated glomerulosclerosis. This effect was related to a reduction in podocyte number, as validated through genetic podocyte labeling in NPHS2.Cre;mT/mG transgenic mice. In RARE-lacZ transgenic mice, albuminuria reduced retinoic acid bioavailability and impaired RARE activation in renal progenitors, inhibiting their differentiation into podocytes. Treatment with retinoic acid restored RARE activity and induced the expression of podocyte markers in renal progenitors, decreasing proteinuria and increasing podocyte number, as demonstrated in serial biopsy specimens. These results suggest that albumin loss through the damaged filtration barrier impairs podocyte regeneration by sequestering retinoic acid and promotes the generation of FSGS lesions. Our findings may explain why reducing proteinuria delays CKD progression and provide a biologic rationale for the clinical use of pharmacologic modulators to induce regression of glomerular diseases. PMID:23949798

On the role of transforming growth factor-beta in the growth inhibitory effects of retinoic acid in human pancreatic cancer cells.

PubMed

Singh, Brahmchetna; Murphy, Richard F; Ding, Xian-Zhong; Roginsky, Alexandra B; Bell, Richard H; Adrian, Thomas E

2007-12-24

Retinoids are potent growth inhibitory and differentiating agents in a variety of cancer cell types. We have shown that retinoids induce growth arrest in all pancreatic cancer cell lines studied, regardless of their p53 and differentiation status. However, the mechanism of growth inhibition is not known. Since TGF-beta2 is markedly induced by retinoids in other cancers and mediates MUC4 expression in pancreatic cancer cells, we investigated the role of TGF-beta in retinoic acid-mediated growth inhibition in pancreatic cancer cells. Retinoic acid markedly inhibited proliferation of two cell lines (Capan-2 and Hs766T) in a concentration and time-dependent manner. Retinoic acid increased TGF-beta2 mRNA content and secretion of the active and latent forms of TGF-beta2 (measured by ELISA and bioassay). The concentrations of active and TGF-beta2 secreted in response to 0.1 - 10 muM retinoic acid were between 1-5 pM. TGF-beta2 concentrations within this range also inhibited proliferation. A TGF-beta neutralizing antibody blocked the growth inhibitory effects of retinoic acid in Capan-2 cells and partially inhibitory the effects in Hs766T cells. These findings indicate that TGF-beta can cause growth inhibition of pancreatic cancer cells, in a p53-independent manner. Furthermore, it demonstrates the fundamental role of TGF-beta in growth inhibition in response to retinoic acid treatment is preserved in vitro.

Biosynthesis of adipic acid via microaerobic hydrogenation of cis,cis-muconic acid by oxygen-sensitive enoate reductase.

PubMed

Sun, Jing; Raza, Muslim; Sun, Xinxiao; Yuan, Qipeng

2018-06-06

Adipic acid (AA) is an important dicarboxylic acid used for the manufacture of nylon and polyurethane plastics. In this study, a novel adipic acid biosynthetic pathway was designed by extending the cis,cis-muconic acid (MA) biosynthesis through biohydrogenation. Enoate reductase from Clostridium acetobutylicum (CaER), an oxygen-sensitive reductase, was demonstrated to have in vivo enzyme activity of converting cis,cis-muconic acid to adipic acid under microaerobic condition. Engineered Escherichia coli strains were constructed to express the whole pathway and accumulated 5.8 ± 0.9 mg/L adipic acid from simple carbon sources. Considering the different oxygen demands between cis,cis-muconic acid biosynthesis and its degradation, a co-culture system was constructed. To improve production, T7 promoter instead of lac promoter was used for higher level expression of the key enzyme CaER and the titer of adipic acid increased to 18.3 ± 0.6 mg/L. To decrease the oxygen supply to downstream strains expressing CaER, Vitreoscilla hemoglobin (VHb) was introduced to upstream strains for its ability on oxygen obtaining. This attempt further improved the production of this novel pathway and 27.6 ± 1.3 mg/L adipic acid was accumulated under microaerobic condition. Copyright © 2018. Published by Elsevier B.V.

Antagonism of hypervitaminosis A-induced anterior neural tube closure defects with a methyl-donor deficiency in murine whole-embryo culture.

PubMed

Santos-Guzmán, Jesús; Arnhold, Thomas; Nau, Heinz; Wagner, Conrad; Fahr, Sharon H; Mao, Gloria E; Caudill, Marie A; Wang, Jennie C; Henning, Susanne M; Swendseid, Marian E; Collins, Michael D

2003-11-01

The interaction of a dietary excess of vitamin A (retinoid) and deficiency of methyl-donor compounds was examined in murine early-organogenesis embryonic development. Female mice were fed one of six diets from the time of vaginal plug detection until gestational d 8.0, when embryos were removed and grown in whole embryo culture for 46 h, using serum from rats fed the same diet for 36 d as the culture medium. The six diets were either methyl-donor deficient (designated -FCM: devoid of folic acid, choline and supplemental L-methionine, but having methionine as a component of the protein portion of the diet) or methyl-donor sufficient (designated +FCM: containing folic acid, choline and L-methionine supplementation), in combination with one of three concentrations of retinyl palmitate (0.016, 0.416 or 4.016 g/kg diet). The high dose of retinyl palmitate induced a failure of anterior neuropore closure and hypoplasia of the visceral arches, both of which were significantly ameliorated by simultaneous administration of the methyl-donor-deficient diet. The primary acidic retinoid detected in the rat serum was 9,13-di-cis-retinoic acid, although we hypothesize that teratogenic retinoids were formed by embryonic biotransformation of the retinyl esters to toxic metabolites. Biochemical measurements of metabolites in relevant pathways were performed. We propose that the amelioration of these malformations may be used to determine biochemical pathways critical for retinoid teratogenesis.

Preliminary Assessment/Site Investigation, Tooele Army Depot, Utah. Volume 2. South Area. Appendixes

DTIC Science & Technology

1988-12-01

METHYL BENZOATE BZOTHP BENZO [B) THIOPHENE BZOTRZ 1H-BENZOThIAZOLE / 1,* 2 , 3 -SENZOThIAZO! E BZPA BENZENEPHOSPHONIC ACID BZYLBR BENZYL BROMIDE / ALPH.A...DEFINITIONS ~ STEST-NAMLE Cil MENECANE C12 DODECANE CI2AMM 8-KETHYLDECANOIC ACID , METHYL ESTER C12DCE CIS-l , 2 -DICHLOROETHENE C13 TRIDECANE C13DCP CIS-1 , 3 ...DBTSPY 4,5-DIMETHYL-2,6-BIS(ThIMETHYLSILOXY)PYRINIDINE DSZFIJR DIBDNZOFURAN DBZTHP DIBENZOThIOPHENE DCAKIBA 2 -METHOXY- 3 ,6-DICHLOROBENZOIC ACID DCBPH

Update on the use of alitretinoin in treating chronic hand eczema.

PubMed

Ghasri, Pedram; Scheinfeld, Noah

2010-04-19

Chronic hand eczema is a debilitating dermatological condition with significant economic, social, and functional impacts. To date, conventional treatments such as topical corticosteroids, phototherapy, and systemic immunosuppressants have yielded disappointing results, owing to either a lack of efficacy or significant adverse events. Oral alitretinoin (9-cis-retinoic acid) is a unique panagonist retinoid with immunomodulatory and anti-inflammatory activity that has emerged as a novel treatment for chronic hand eczema. Several large-scale clinical studies have demonstrated oral alitretinoin's high efficacy rate of 28% to 89%, its safe tolerability profile, and its positive impact on quality of life, validating it as a therapeutic option for patients with severe chronic hand eczema refractory to standard treatment.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Basu, Partha, E-mail: BasuP@iarc.fr; Jenson, Alfred Bennett; Majhi, Tapas

Purpose: Because a combination of retinoic acid, interferon-alpha, and radiation therapy demonstrated synergistic action and effectiveness to treat advanced cervical cancers in earlier studies, we designed this randomized phase 2 open-label trial to assess efficacy and safety of interferon alpha-2b (IFN) and 13-cis-retinoic acid (RA) administered concomitantly with radiation therapy (IFN-RA-radiation) to treat stage III cervical cancer. Methods and Materials: Stage III cervical cancer patients were randomized to study and control groups in a 1:1 ratio. All patients were treated with radiation therapy; study arm patients received IFN (3 × 10{sup 6} IU subcutaneously) 3 times a week for 4 weeks and dailymore » RA (40 mg orally) for 30 days starting on day 1 of radiation, whereas control arm patients received weekly cisplatinum (40 mg/m{sup 2}) for 5 weeks during radiation. Patients were followed for 3 years. The primary endpoint was overall survival at 3 years. Results: Patients in the study (n=104) and control (n=105) groups were comparable for clinicopathological characteristics, radiation therapy–related variables and treatment response. Proportions of disease-free patients in the study and control groups were 38.5% and 44.8%, respectively, after median follow-up of 29.2 months. Hazard ratios were 0.67 (95% confidence interval [CI]: 0.44-1.01) and 0.69 (95% CI: 0.44-1.06) for overall and disease-fee survival, respectively, comparing the study group to control, and demonstrated an inferior outcome with RA-IFN-radiation, although differences were statistically nonsignificant. Kaplan-Meier curves of disease-free and overall survival probabilities also showed inferior survival in the study group compared to those in the control. Acute toxicities of chemoradiation were significantly higher with 2 acute toxicity-related deaths. Conclusions: Treatment with RA-IFN-radiation did not demonstrate survival advantage over chemoradiation despite being less toxic. The trends predicted an inferior outcome with the RA-IFN combination.« less

Foraging in maize field areas: A risky business?

PubMed

Boily, Monique; Aras, Philippe; Jumarie, Catherine

2017-12-01

In Quebec, Canada, the cultivation of maize dominates the agricultural territory. This crop requires a sustained supply of fertilizers from different sources: chemical, natural or from residual materials (sludge). These amendments contain metallic trace elements, which may lead to metal-contaminated maize pollen, a possible source of prooxidants for the foraging bees. Our objective was to determine whether maize fields environment influences the oxidation processes and the accumulation of metals in bees. A few days prior to pollen shedding, beehives were installed in maize fields: one organically grown (site A) and three conventionally grown (sites B, C and D). Soil, maize pollen and bees were analyzed for metal content. Every 15days, bees were collected and analyzed for peroxidation of lipids, metallothionein-like proteins (MTLPs), proteins, retinoids and lipophilic antioxidants (carotenoids and α-tocopherol). The compound β-carotene was the most abundant in bees from all sites, followed by α-carotene, β-cryptoxanthin, α-cryptoxanthin, zeaxanthin and lutein. Retinaldehyde and retinol varied according to times and sites without demonstrating clear trends. However, significant differences between sites were noted in 13-cis-retinoic acid and two retinoic acid metabolites measured in bees, suggesting alteration in the reduction-oxidation processes. In line with these results, the level of lipid peroxidation was globally higher in sites B, C and D compared with the organic site. Higher concentrations of metals were observed in soil and pollen from the field A, but bees metal contents were equal or less than those measured in bees from other sites. Higher bee MTLP levels were measured in sites B, C and D. For most sampling times, the discriminant analysis revealed that the conditions were distinguished by the oxidation processes in bees. Our data suggest that bees foraging in conventionally grown maize fields are at risk of increased oxidative damages which can alter the fine regulation of retinoids. Copyright © 2017 Elsevier B.V. All rights reserved.

MDI 301, a nonirritating retinoid, improves abrasion wound healing in damaged/atrophic skin

PubMed Central

Warner, Roscoe L.; Bhagavathula, Narasimharao; Nerusu, Kamalakar; Hanosh, Andrew; McClintock, Shannon D.; Naik, Madhav K.; Johnson, Kent J.; Ginsburg, Isaac; Varani, James

2010-01-01

MDI 301 is a picolinic acid-substituted ester of 9-cis retinoic acid. It has been shown in the past that MDI 301 increases epidermal thickness, decreases matrix metalloproteinase (MMP) activity, and increases procollagen synthesis in organ-cultured human skin. Unlike all-trans retinoic acid (RA), MDI 301 does not induce expression of proinflammatory cytokines or induce expression of leukocyte adhesion molecules in human skin. In the present study we examined topical MDI 301 treatment for ability to improve the structure and function of skin in three models of skin damage in rodents and for ability to improve abrasion wound healing in these models. MDI 301 was applied daily to the skin of rats treated with the potent corticosteroid, clobetasol propionate, to the skin of diabetic rats (8 weeks posttreatment with streptozotocin) and to the skin of aged (14–16-month-old) rats. In all three models, subsequently induced abrasion wounds healed more rapidly in the retinoid-treated animals than in vehicle-treated controls. Immediately after complete wound closure, tissue from the wound site (as well as from a control site) was put into organ culture and maintained for 3 days. At the end of the incubation period, culture fluids were assessed for soluble type I collagen and for MMPs-2 and -9. In all three models, the level of type I collagen was increased and MMP levels were decreased by MDI 301. In all three models, skin irritation during the retinoid-treatment phase was virtually nonexistent. PMID:18211583

New approaches to male non-hormonal contraception.

PubMed

Nya-Ngatchou, Jean-Jacques; Amory, John K

2013-03-01

A non-hormonal male contraceptive is a contraceptive that does not involve the administration of hormones or hormone blockers. This review will focus on the use of lonidamine derivatives and inhibitors of retinoic acid biosynthesis and function as approaches to male non-hormonal contraception. Two current lonidamine derivatives, adjudin and H2-gamendazole, are in development as male contraceptives. These potent anti-spermatogenic compounds impair the integrity of the apical ectoplasmic specialization, resulting in premature spermiation and infertility. Another approach to male contraceptive development is the inhibition of retinoic acid in the testes, as retinoic acid signaling is necessary for spermatogenesis. The administration of the retinoic acid receptor antagonist BMS-189453 reversibly inhibits spermatogenesis in mice. Similarly, oral dosing of WIN 18,446, which inhibits testicular retinoic acid biosynthesis, effectively contracepts rabbits. Hopefully, one of these approaches to non-hormonal male contraception will prove to be safe and effective in future clinical trials. Copyright © 2013 Elsevier Inc. All rights reserved.

MSX-1 gene expression and regulation in embryonic palatal tissue.

PubMed

Nugent, P; Greene, R M

1998-01-01

The palatal cleft seen in Msx-1 knock-out mice suggests a role for this gene in normal palate development. The cleft is presumed secondary to tooth and jaw malformations, since in situ hybridization suggests that Msx-1 mRNA is not highly expressed in developing palatal tissue. In this study we demonstrate, by Northern blot analysis, the expression of Msx-1, but not Msx-2, in the developing palate and in primary cultures of murine embryonic palate mesenchymal cells. Furthermore, we propose a role for Msx-1 in retinoic acid-induced cleft palate, since retinoic acid inhibits Msx-1 mRNA expression in palate mesenchymal cells. We also demonstrate that transforming growth factor beta inhibits Msx-1 mRNA expression in palate mesenchymal cells, with retinoic acid and transforming growth factor beta acting synergistically when added simultaneously to these cells. These data suggest a mechanistic interaction between retinoic acid, transforming growth factor beta, and Msx-1 in the etiology of retinoic acid-induced cleft palate.

An Effective Algorithm for Management of Noses with Thick Skin.

PubMed

Guyuron, Bahman; Lee, Michelle

2017-04-01

Thicker nasal skin blunts the definition of the underlying osseocartilaginous frame and the delicate topography of the nose posing additional challenges in producing desirable tip definition. Despite the recognized challenge in this patient population, there is a paucity of literature on how to overcome this problem. The goal of this article is to provide a systematic algorithm to manage patients with thick nasal skin. Approach to the thick nasal skin patient begins with an evaluation of the etiology of their skin thickness. Skin thickness secondary to sebaceous overactivity is diminished with the use of retinoic acid derivatives, lasers or isotretinoin (Accutane), commonly under the advice of the dermatologist. Rhinoplasty maneuvers include open technique, raising a healthy and reasonably thick skin flap overlying the tip, removing the remaining fat overlying and between the domes, creating a firm cartilaginous frame and eliminating dead space using the supratip suture reported by the senior author, and trimming redundant nasal skin envelope when indicated. This systematic approach has been greatly effective in achieving often predictable and aesthetically pleasing rhinoplasty results. This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Unveiling of novel regio-selective fatty acid double bond hydratases from Lactobacillus acidophilus involved in the selective oxyfunctionalization of mono- and di-hydroxy fatty acids.

PubMed

Kim, Kyoung-Rok; Oh, Hye-Jin; Park, Chul-Soon; Hong, Seung-Hye; Park, Ji-Young; Oh, Deok-Kun

2015-11-01

The aim of this study is the first time demonstration of cis-12 regio-selective linoleate double-bond hydratase. Hydroxylation of fatty acids, abundant feedstock in nature, is an emerging alternative route for many petroleum replaceable products thorough hydroxy fatty acids, carboxylic acids, and lactones. However, chemical route for selective hydroxylation is still quite challenging owing to low selectivity and many environmental concerns. Hydroxylation of fatty acids by hydroxy fatty acid forming enzymes is an important route for selective biocatalytic oxyfunctionalization of fatty acids. Therefore, novel fatty acid hydroxylation enzymes should be discovered. The two hydratase genes of Lactobacillus acidophilus were identified by genomic analysis, and the expressed two recombinant hydratases were identified as cis-9 and cis-12 double-bond selective linoleate hydratases by in vitro functional validation, including the identification of products and the determination of regio-selectivity, substrate specificity, and kinetic parameters. The two different linoleate hydratases were the involved enzymes in the 10,13-dihydroxyoctadecanoic acid biosynthesis. Linoleate 13-hydratase (LHT-13) selectively converted 10 mM linoleic acid to 13S-hydroxy-9(Z)-octadecenoic acid with high titer (8.1 mM) and yield (81%). Our study will expand knowledge for microbial fatty acid-hydroxylation enzymes and facilitate the designed production of the regio-selective hydroxy fatty acids for useful chemicals from polyunsaturated fatty acid feedstocks. © 2015 Wiley Periodicals, Inc.

Proliferation versus Differentiation: Redefining Retinoic Acid's Role.

PubMed

Mosher, Kira Irving; Schaffer, David V

2018-06-05

Retinoic acid is commonly used in culture to differentiate stem cells into neurons and has established neural differentiation functions in vivo in developing and adult organisms. In this issue of Stem Cell Reports, Mishra et al. (2018) broaden its role in stem cell functions, showing that retinoic acid is necessary for stem and progenitor cell proliferation in the adult brain. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Changes in expression of the lysosomal membrane glycoprotein, LAMP-1 in interdigital regions during embryonic mouse limb development, in vivo and in vitro.

PubMed

Stewart, S; Yi, S; Kassabian, G; Mayo, M; Sank, A; Shuler, C

2000-06-01

Syndactyly, a failure of the digits to separate into individual units, affects about 8 to 9 per 1000 newborns and results from an aberration of the normal development of the interdigital tissues. Limb digit separation is the result of programmed cell death (apoptosis). Lysosomes play a role in the process of cell self-destruction. Our experiment was designed to test the hypothesis that the intensity of interdigital lysosomes increases during the separation of digits in vivo and in vitro. The primary mouse monoclonal antibody, 1D4B, detects the presence of lysosomes by identifying the LAMP-1 glycoprotein on the lysosome cell membrane. In our experiment this antibody immunodetected interdigital lysosome proteins in serial sections of limbs from Swiss-Webster mouse embryos, gestational ages E12.5 through E15, key developmental stages for digit separation. Digit separation was associated with an increase in intensity of lysosomal protein staining. In E12.5 limbs, the presence of lysosomes was enriched in the distal aspect of the interdigital tissue. However, the number of lysosomes markedly increased in the E13 and E14 limbs, including the entire length and width of the interdigital tissue in the E14 limbs. This lysosomal protein presence in E14 limbs was significant compared to E12.5, E13, and E15 limbs. By day 12.5, the mouse embryo limb is committed to digit separation. Addition of retinoic acid to the culture medium of limbs earlier in development, such as E12, results in induction of the process of digit separation. Cultured E12 limbs that did not receive an addition of retinoic acid, did not show digit separation. We conclude that in the limb development process, the enrichment in interdigit LAMP-1 proteins, may indicate a relationship between lysosomes, apoptosis, and digit separation. We also conclude that retinoic acid has an important role in digit separation in vivo, as shown in limb development, and demonstrated through the addition of retinoic acid to media of cultured tissues.

Quantitative analysis of retinoids in biological fluids by high-performance liquid chromatography using column switching. I. Determination of isotretinoin and tretinoin and their 4-oxo metabolites in plasma.

PubMed

Wyss, R; Bucheli, F

1988-02-26

A fully automated gradient high-performance liquid chromatographic method for the determination of isotretinoin, tretinoin and their 4-oxo metabolites in plasma was developed, using the column-switching technique. After dilution with an internal standard solution containing 20% acetonitrile, 0.5 ml of the sample was injected onto a precolumn (17 X 4.6 mm I.D.), filled with C18 Corasil 37-53 micron. Proteins and polar plasma components were washed out using 1% ammonium acetate-acetonitrile (9:1, v/v) as mobile phase 1. After valve switching, the retained components were transferred to the analytical column in the backflush mode, separated by gradient elution and detected at 360 nm by UV detection. Using two coupled reversed-phase columns (125 mm long), the separation of cis and trans isomers was possible, and all four compounds could be quantified down to 2 ng/ml of plasma. The inter-assay precision in the concentration range 20-100 ng/ml was between 1.0 and 4.7% for all compounds.

Cloning retinoid and peroxisome proliferator-activated nuclear receptors of the Pacific oyster and in silico binding to environmental chemicals

PubMed Central

Vogeler, Susanne; Galloway, Tamara S.; Isupov, Michail

2017-01-01

Disruption of nuclear receptors, a transcription factor superfamily regulating gene expression in animals, is one proposed mechanism through which pollution causes effects in aquatic invertebrates. Environmental pollutants have the ability to interfere with the receptor’s functions through direct binding and inducing incorrect signals. Limited knowledge of invertebrate endocrinology and molecular regulatory mechanisms, however, impede the understanding of endocrine disruptive effects in many aquatic invertebrate species. Here, we isolated three nuclear receptors of the Pacific oyster, Crassostrea gigas: two isoforms of the retinoid X receptor, CgRXR-1 and CgRXR-2, a retinoic acid receptor ortholog CgRAR, and a peroxisome proliferator-activated receptor ortholog CgPPAR. Computer modelling of the receptors based on 3D crystal structures of human proteins was used to predict each receptor’s ability to bind to different ligands in silico. CgRXR showed high potential to bind and be activated by 9-cis retinoic acid and the organotin tributyltin (TBT). Computer modelling of CgRAR revealed six residues in the ligand binding domain, which prevent the successful interaction with natural and synthetic retinoid ligands. This supports an existing theory of loss of retinoid binding in molluscan RARs. Modelling of CgPPAR was less reliable due to high discrepancies in sequence to its human ortholog. Yet, there are suggestions of binding to TBT, but not to rosiglitazone. The effect of potential receptor ligands on early oyster development was assessed after 24h of chemical exposure. TBT oxide (0.2μg/l), all-trans retinoic acid (ATRA) (0.06 mg/L) and perfluorooctanoic acid (20 mg/L) showed high effects on development (>74% abnormal developed D-shelled larvae), while rosiglitazone (40 mg/L) showed no effect. The results are discussed in relation to a putative direct (TBT) disruption effect on nuclear receptors. The inability of direct binding of ATRA to CgRAR suggests either a disruptive effect through a pathway excluding nuclear receptors or an indirect interaction. Our findings provide valuable information on potential mechanisms of molluscan nuclear receptors and the effects of environmental pollution on aquatic invertebrates. PMID:28426724

ALDH1A1 Deficiency in Gorlin Syndrome Suggests a Central Role for Retinoic Acid and ATM Deficits in Radiation Carcinogenesis.

PubMed

Weber, Thomas J; Magnaldo, Thierry; Xiong, Yijia

2014-09-11

We hypothesize that aldehyde dehydrogenase 1A1 (ALDH1A1) deficiency will result in impaired ataxia-telangiectasia mutated (ATM) activation in a retinoic acid-sensitive fashion. Data supporting this hypothesis include (1) reduced ATM activation in irradiated primary dermal fibroblasts from ALDH1A1-deficient Gorlin syndrome patients (GDFs), relative to ALDH1A1-positive normal human dermal fibroblasts (NHDFs) and (2) increased ATM activation by X-radiation in GDFs pretreated with retinoic acid, however, the impact of donor variability on ATM activation in fibroblasts was not assessed and is a prudent consideration in future studies. Clonogenic survival of irradiated cells showed differential responses to retinoic acid as a function of treatment time. Long-term (5 Day) retinoic acid treatment functioned as a radiosensitizer and was associated with downregulation of ATM protein levels. Short-term (7 h) retinoic acid treatment showed a trend toward increased survival of irradiated cells and did not downregulate ATM protein levels. Using a newly developed IncubATR technology, which defines changes in bulk chemical bond patterns in live cells, we can discriminate between the NHDF and GDF phenotypes, but treatment of GDFs with retinoic acid does not induce reversion of bulk chemical bond patterns associated with GDFs toward the NHDF phenotype. Collectively, our preliminary investigation of the Gorlin phenotype has identified deficient ALDH1A1 expression associated with deficient ATM activation as a possible susceptibility factor that is consistent with the high incidence of spontaneous and radiation-induced carcinogenesis in these patients. The IncubATR technology exhibits sufficient sensitivity to detect phenotypic differences in live cells that may be relevant to radiation health effects.

A Dominant Mutation in Nuclear Receptor Interacting Protein 1 Causes Urinary Tract Malformations via Dysregulation of Retinoic Acid Signaling.

PubMed

Vivante, Asaf; Mann, Nina; Yonath, Hagith; Weiss, Anna-Carina; Getwan, Maike; Kaminski, Michael M; Bohnenpoll, Tobias; Teyssier, Catherine; Chen, Jing; Shril, Shirlee; van der Ven, Amelie T; Ityel, Hadas; Schmidt, Johanna Magdalena; Widmeier, Eugen; Bauer, Stuart B; Sanna-Cherchi, Simone; Gharavi, Ali G; Lu, Weining; Magen, Daniella; Shukrun, Rachel; Lifton, Richard P; Tasic, Velibor; Stanescu, Horia C; Cavaillès, Vincent; Kleta, Robert; Anikster, Yair; Dekel, Benjamin; Kispert, Andreas; Lienkamp, Soeren S; Hildebrandt, Friedhelm

2017-08-01

Congenital anomalies of the kidney and urinary tract (CAKUT) are the most common cause of CKD in the first three decades of life. However, for most patients with CAKUT, the causative mutation remains unknown. We identified a kindred with an autosomal dominant form of CAKUT. By whole-exome sequencing, we identified a heterozygous truncating mutation (c.279delG, p.Trp93fs*) of the nuclear receptor interacting protein 1 gene ( NRIP1 ) in all seven affected members. NRIP1 encodes a nuclear receptor transcriptional cofactor that directly interacts with the retinoic acid receptors (RARs) to modulate retinoic acid transcriptional activity. Unlike wild-type NRIP1, the altered NRIP1 protein did not translocate to the nucleus, did not interact with RAR α , and failed to inhibit retinoic acid-dependent transcriptional activity upon expression in HEK293 cells. Notably, we also showed that treatment with retinoic acid enhanced NRIP1 binding to RAR α RNA in situ hybridization confirmed Nrip1 expression in the developing urogenital system of the mouse. In explant cultures of embryonic kidney rudiments, retinoic acid stimulated Nrip1 expression, whereas a pan-RAR antagonist strongly reduced it. Furthermore, mice heterozygous for a null allele of Nrip1 showed a CAKUT-spectrum phenotype. Finally, expression and knockdown experiments in Xenopus laevis confirmed an evolutionarily conserved role for NRIP1 in renal development. These data indicate that dominant NRIP1 mutations can cause CAKUT by interference with retinoic acid transcriptional signaling, shedding light on the well documented association between abnormal vitamin A levels and renal malformations in humans, and suggest a possible gene-environment pathomechanism in this disease. Copyright © 2017 by the American Society of Nephrology.

Morphological and functional differentiation in BE(2)-M17 human neuroblastoma cells by treatment with Trans-retinoic acid

PubMed Central

2013-01-01

Background Immortalized neuronal cell lines can be induced to differentiate into more mature neurons by adding specific compounds or growth factors to the culture medium. This property makes neuronal cell lines attractive as in vitro cell models to study neuronal functions and neurotoxicity. The clonal human neuroblastoma BE(2)-M17 cell line is known to differentiate into a more prominent neuronal cell type by treatment with trans-retinoic acid. However, there is a lack of information on the morphological and functional aspects of these differentiated cells. Results We studied the effects of trans-retinoic acid treatment on (a) some differentiation marker proteins, (b) types of voltage-gated calcium (Ca2+) channels and (c) Ca2+-dependent neurotransmitter ([3H] glycine) release in cultured BE(2)-M17 cells. Cells treated with 10 μM trans-retinoic acid (RA) for 72 hrs exhibited marked changes in morphology to include neurite extensions; presence of P/Q, N and T-type voltage-gated Ca2+ channels; and expression of neuron specific enolase (NSE), synaptosomal-associated protein 25 (SNAP-25), nicotinic acetylcholine receptor α7 (nAChR-α7) and other neuronal markers. Moreover, retinoic acid treated cells had a significant increase in evoked Ca2+-dependent neurotransmitter release capacity. In toxicity studies of the toxic gas, phosgene (CG), that differentiation of M17 cells with RA was required to see the changes in intracellular free Ca2+ concentrations following exposure to CG. Conclusion Taken together, retinoic acid treated cells had improved morphological features as well as neuronal characteristics and functions; thus, these retinoic acid differentiated BE(2)-M17 cells may serve as a better neuronal model to study neurobiology and/or neurotoxicity. PMID:23597229

Morphological and functional differentiation in BE(2)-M17 human neuroblastoma cells by treatment with Trans-retinoic acid.

PubMed

Andres, Devon; Keyser, Brian M; Petrali, John; Benton, Betty; Hubbard, Kyle S; McNutt, Patrick M; Ray, Radharaman

2013-04-18

Immortalized neuronal cell lines can be induced to differentiate into more mature neurons by adding specific compounds or growth factors to the culture medium. This property makes neuronal cell lines attractive as in vitro cell models to study neuronal functions and neurotoxicity. The clonal human neuroblastoma BE(2)-M17 cell line is known to differentiate into a more prominent neuronal cell type by treatment with trans-retinoic acid. However, there is a lack of information on the morphological and functional aspects of these differentiated cells. We studied the effects of trans-retinoic acid treatment on (a) some differentiation marker proteins, (b) types of voltage-gated calcium (Ca2+) channels and (c) Ca2+-dependent neurotransmitter ([3H] glycine) release in cultured BE(2)-M17 cells. Cells treated with 10 μM trans-retinoic acid (RA) for 72 hrs exhibited marked changes in morphology to include neurite extensions; presence of P/Q, N and T-type voltage-gated Ca2+ channels; and expression of neuron specific enolase (NSE), synaptosomal-associated protein 25 (SNAP-25), nicotinic acetylcholine receptor α7 (nAChR-α7) and other neuronal markers. Moreover, retinoic acid treated cells had a significant increase in evoked Ca2+-dependent neurotransmitter release capacity. In toxicity studies of the toxic gas, phosgene (CG), that differentiation of M17 cells with RA was required to see the changes in intracellular free Ca2+ concentrations following exposure to CG. Taken together, retinoic acid treated cells had improved morphological features as well as neuronal characteristics and functions; thus, these retinoic acid differentiated BE(2)-M17 cells may serve as a better neuronal model to study neurobiology and/or neurotoxicity.

A comparative study of the effects of retinol and retinoic acid on histological, molecular, and clinical properties of human skin.

PubMed

Kong, Rong; Cui, Yilei; Fisher, Gary J; Wang, Xiaojuan; Chen, Yinbei; Schneider, Louise M; Majmudar, Gopa

2016-03-01

All-trans retinol, a precursor of retinoic acid, is an effective anti-aging treatment widely used in skin care products. In comparison, topical retinoic acid is believed to provide even greater anti-aging effects; however, there is limited research directly comparing the effects of retinol and retinoic acid on skin. In this study, we compare the effects of retinol and retinoic acid on skin structure and expression of skin function-related genes and proteins. We also examine the effect of retinol treatment on skin appearance. Skin histology was examined by H&E staining and in vivo confocal microscopy. Expression levels of skin genes and proteins were analyzed using RT-PCR and immunohistochemistry. The efficacy of a retinol formulation in improving skin appearance was assessed using digital image-based wrinkle analysis. Four weeks of retinoic acid and retinol treatments both increased epidermal thickness, and upregulated genes for collagen type 1 (COL1A1), and collagen type 3 (COL3A1) with corresponding increases in procollagen I and procollagen III protein expression. Facial image analysis showed a significant reduction in facial wrinkles following 12 weeks of retinol application. The results of this study demonstrate that topical application of retinol significantly affects both cellular and molecular properties of the epidermis and dermis, as shown by skin biopsy and noninvasive imaging analyses. Although the magnitude tends to be smaller, retinol induces similar changes in skin histology, and gene and protein expression as compared to retinoic acid application. These results were confirmed by the significant facial anti-aging effect observed in the retinol efficacy clinical study. © 2015 Wiley Periodicals, Inc.

Binding of vitamin A with milk α- and β-caseins.

PubMed

Bourassa, P; N'soukpoé-Kossi, C N; Tajmir-Riahi, H A

2013-05-01

The binding sites of retinol and retinoic acid with milk α- and β-caseins were determined, using constant protein concentration and various retinoid contents. FTIR, UV-visible and fluorescence spectroscopic methods as well as molecular modelling were used to analyse retinol and retinoic acid binding sites, the binding constant and the effect of retinoid complexation on the stability and conformation of caseins. Structural analysis showed that retinoids bind caseins via both hydrophilic and hydrophobic contacts with overall binding constants of K(retinol-)(α)(-caseins)=1.21 (±0.4)×10(5) M(-1) and K(retinol-)(β)(-caseins)=1.11 (±0.5)×10(5) M(-1) and K(retinoic acid-)(α)(-caseins)=6.2 (±0.6)×10(4) M(-1) and K(retinoic acid-)(β)(-caseins)=6.3 (±0.6)×10(4) M(-1). The number of bound retinol molecules per protein (n) was 1.5 (±0.1) for α-casein and 1.0 (±0.1) for β-casein, while 1 molecule of retinoic acid was bound in the α- and β-casein complexes. Molecular modelling showed different binding sites for retinol and retinoic acid on α- and β-caseins with more stable complexes formed with α-casein. Retinoid-casein complexation induced minor alterations of protein conformation. Caseins might act as carriers for transportation of retinoids to target molecules. Copyright © 2012 Elsevier Ltd. All rights reserved.

The negligible systemic availability of retinoids with multiple and excessive topical application of isotretinoin 0.05% gel (Isotrex) in patients with acne vulgaris.

PubMed

Jensen, B K; McGann, L A; Kachevsky, V; Franz, T J

1991-03-01

The potential systemic availability of retinoids from topically applied isotretinoin was assessed in 12 men with acne vulgaris. Isotretinoin 0.05% gel was applied to patients at a daily dose of 20 gm (equivalent to 10 mg of isotretinoin) over a 1900 cm2 surface area of skin on the face, back, and chest for 30 days. Blood samples were collected throughout the study and up to 48 hours after the last topical application; they were assayed for isotretinoin, tretinoin, and 4-oxo-isotretinoin by specific high-performance liquid chromatography. Plasma concentrations of isotretinoin, tretinoin, and 4-oxo-isotretinoin were not measurable (less than 20 ng/ml) at any time. Most adverse experiences were cutaneous; a few systemic adverse experiences were judged to be remotely related to topical drug administration. The lack of measurable plasma concentrations of isotretinoin, tretinoin, or 4-oxo-isotretinoin and systemic adverse experiences indicates negligible systemic availability of retinoids even after multiple application of isotretinoin 0.05% gel at doses approximately 12 times greater than normal daily use.

Conformational Analysis of Retinoic Acids: Effects of Steric Interactions on Nonplanar Conjugated Polyenes

PubMed Central

Cox, Bryan D.; Muccio, Donald D.; Hamilton, Tracy P.

2013-01-01

Retinoic acids and other vitamin A analogs contain a trimethylcyclohexenyl ring in conjugation with a polyene chain joined at carbon-6 (C6) and carbon-7 (C7). A MP2-SCS/cc-pVDZ// B3LYP/6-31G(d) 2-D potential energy surface was computed for all-trans retinoic acid, which had 6 minima (3 enantiomeric pairs). The global minima were distorted s-gauche enantiomers (6–7 = 53°) with half-chair conformations of the ring. Distorted s-gauche enantiomers (6–7 = 55°) with inverted half-chair ring conformations were 1.7 kJ/mol above the global minima. The s-trans enantiomers (6–7 = 164°) were 11.3 kJ/mol above the global minima. Steric energies were computed by the method of Guo and Karplus to identify key structural elements in retinoic acids which determines their conformation. Small molecule crystal structures in the CCDC database with trimethylcyclohexenyl ring and exocyclic double bonds have ring-chain geometries near to one of the 6 energy minima of retinoic acids, except for retinaldehyde iminium cations. PMID:25798372

Conformational Analysis of Retinoic Acids: Effects of Steric Interactions on Nonplanar Conjugated Polyenes.

PubMed

Cox, Bryan D; Muccio, Donald D; Hamilton, Tracy P

2013-05-01

Retinoic acids and other vitamin A analogs contain a trimethylcyclohexenyl ring in conjugation with a polyene chain joined at carbon-6 (C6) and carbon-7 (C7). A MP2-SCS/cc-pVDZ// B3LYP/6-31G(d) 2-D potential energy surface was computed for all- trans retinoic acid, which had 6 minima (3 enantiomeric pairs). The global minima were distorted s-gauche enantiomers ( 6-7 = 53°) with half-chair conformations of the ring. Distorted s-gauche enantiomers ( 6-7 = 55°) with inverted half-chair ring conformations were 1.7 kJ/mol above the global minima. The s-trans enantiomers ( 6-7 = 164°) were 11.3 kJ/mol above the global minima. Steric energies were computed by the method of Guo and Karplus to identify key structural elements in retinoic acids which determines their conformation. Small molecule crystal structures in the CCDC database with trimethylcyclohexenyl ring and exocyclic double bonds have ring-chain geometries near to one of the 6 energy minima of retinoic acids, except for retinaldehyde iminium cations.

Fatty acids attached to all-trans-astaxanthin alter its cis-trans equilibrium, and consequently its stability, upon light-accelerated autoxidation.

PubMed

de Bruijn, Wouter J C; Weesepoel, Yannick; Vincken, Jean-Paul; Gruppen, Harry

2016-03-01

Fatty acid esterification, common in naturally occurring astaxanthin, has been suggested to influence both colour stability and degradation of all-trans-astaxanthin. Therefore, astaxanthin stability was studied as influenced by monoesterification and diesterification with palmitate. Increased esterification decelerated degradation of all-trans-astaxanthin (RP-UHPLC-PDA), whereas, it had no influence on colour loss over time (spectrophotometry). This difference might be explained by the observation that palmitate esterification influenced the cis-trans equilibrium. Free astaxanthin produced larger amounts of 9-cis isomer whereas monopalmitate esterification resulted in increased 13-cis isomerization. The molar ratios of 9-cis:13-cis after 60min were 1:1.7 (free), 1:4.8 (monopalmitate) and 1:2.6 (dipalmitate). The formation of 9-cis astaxanthin, with its higher molar extinction coefficient than that of all-trans-astaxanthin, might compensate for colour loss induced by conjugated double bond cleavage. As such, it was concluded that spectrophotometry is not an accurate measure of the degradation of the all-trans-astaxanthin molecule. Copyright © 2015 Elsevier Ltd. All rights reserved.

Toxic responses of Sox2 gene in the regeneration of the earthworm Eisenia foetida exposed to Retnoic acid.

PubMed

Tao, Jing; Rong, Wei; Diao, Xiaoping; Zhou, Hailong

2018-01-01

Exogenous retinoic acid delays and disturbs the regeneration of Eisenia foetida. The stem cell pluripotency factor, Sox2, can play a crucial role in cell reprogramming and dedifferentiation. In this study, we compared the regeneration of Eisenia foetida in different segments after amputation and the effects of retinoic acid on the regeneration of different segments. The results showed that the regeneration speed of the head and tail was slightly faster than the middle part, and retinoic acid disrupted and delayed the regeneration of the earthworm. The qRT-PCR and Western blot analysis showed that the expression of the Sox2 gene and Sox2 protein was highest on the seventh day in different segments (p<0.05). After treatment with retinoic acid, the expression level of the Sox2 gene and Sox2 protein was significantly reduced (p<0.05). The results indicated that the regeneration of earthworms and the formation of blastema are related to the expression of the Sox2 gene and protein. Retinoic acid delays and interferes with the regeneration of the earthworm by affecting the expression levels of the Sox2 gene and protein. Copyright © 2017 Elsevier Inc. All rights reserved.

Chemoprevention of Lung Cancer

PubMed Central

Szabo, Eva; Mao, Jenny T.; Lam, Stephen; Reid, Mary E.

2013-01-01

Background: Lung cancer is the most common cause of cancer death in men and women in the United States. Cigarette smoking is the main risk factor. Former smokers are at a substantially increased risk of developing lung cancer compared with lifetime never smokers. Chemoprevention refers to the use of specific agents to reverse, suppress, or prevent the process of carcinogenesis. This article reviews the major agents that have been studied for chemoprevention. Methods: Articles of primary, secondary, and tertiary prevention trials were reviewed and summarized to obtain recommendations. Results: None of the phase 3 trials with the agents β-carotene, retinol, 13-cis-retinoic acid, α-tocopherol, N-acetylcysteine, acetylsalicylic acid, or selenium has demonstrated beneficial and reproducible results. To facilitate the evaluation of promising agents and to lessen the need for a large sample size, extensive time commitment, and expense, surrogate end point biomarker trials are being conducted to assist in identifying the most promising agents for later-stage chemoprevention trials. With the understanding of important cellular signaling pathways and the expansion of potentially important targets, agents (many of which target inflammation and the arachidonic acid pathway) are being developed and tested which may prevent or reverse lung carcinogenesis. Conclusions: By integrating biologic knowledge, additional early-phase trials can be performed in a reasonable time frame. The future of lung cancer chemoprevention should entail the evaluation of single agents or combinations that target various pathways while working toward identification and validation of intermediate end points. PMID:23649449

Update on the use of alitretinoin in treating chronic hand eczema

PubMed Central

Ghasri, Pedram; Scheinfeld, Noah

2010-01-01

Chronic hand eczema is a debilitating dermatological condition with significant economic, social, and functional impacts. To date, conventional treatments such as topical corticosteroids, phototherapy, and systemic immunosuppressants have yielded disappointing results, owing to either a lack of efficacy or significant adverse events. Oral alitretinoin (9-cis-retinoic acid) is a unique panagonist retinoid with immunomodulatory and anti-inflammatory activity that has emerged as a novel treatment for chronic hand eczema. Several large-scale clinical studies have demonstrated oral alitretinoin’s high efficacy rate of 28% to 89%, its safe tolerability profile, and its positive impact on quality of life, validating it as a therapeutic option for patients with severe chronic hand eczema refractory to standard treatment. PMID:21437060

The nitrite-oxidizing community in activated sludge from a municipal wastewater treatment plant determined by fatty acid methyl ester-stable isotope probing.

PubMed

Kruse, Myriam; Zumbrägel, Sabine; Bakker, Evert; Spieck, Eva; Eggers, Till; Lipski, André

2013-10-01

Metabolically-active autotrophic nitrite oxidizers from activated sludge were labeled with (13)C-bicarbonate under exposure to different temperatures and nitrite concentrations. The labeled samples were characterized by FAME-SIP (fatty acid methyl ester-stable isotope probing). The compound cis-11-palmitoleic acid, which is the major lipid of the most abundant nitrite oxidizer in activated sludge, Candidatus Nitrospira defluvii, showed (13)C-incorporation in all samples exposed to 3 mM nitrite. Subsequently, the lipid cis-7-palmitoleic acid was labeled, and it indicated the activity of a nitrite oxidizer that was different from the known Nitrospira taxa in activated sludge. The highest incorporation of cis-7-palmitoleic acid label was found after incubation with a nitrite concentration of 0.3 mM at 17 and 22°C. While activity of Nitrobacter populations could not be detected by the FAME-SIP approach, an unknown nitrite oxidizer with the major lipid cis-9 isomer of palmitoleic acid exhibited (13)C-incorporation at 28°C with 30 mM nitrite. These results indicated flexibility of nitrite-oxidizing guilds in a complex community responding to different conditions. Labeled lipids so far not described for activated sludge-associated nitrifiers indicated the presence of unknown nitrite oxidizers in this habitat. The FAME-SIP-based information can be used to define appropriate conditions for the enrichment of nitrite-oxidizing guilds from complex samples. Copyright © 2013 Elsevier GmbH. All rights reserved.

Improving the Isotretinoin Photostability by Incorporating in Microemulsion Matrix

PubMed Central

Patel, Mrunali R.; Patel, Rashmin B.; Parikh, Jolly R.; Patel, Bharat G.

2011-01-01

The present paper demonstrates the increased photostability of isotretinoin when loaded in microemulsion. The photodegradation of isotretinoin, in methanol and microemulsion formulation was studied under direct sun light. The photodegradation process was monitored by UV spectrophotometry. In methanol solution, isotretinoin undergoes complete photodegradation just within a few minutes of light exposure. Isotretinoin incorporated in microemulsion formulation showed an increased stability in comparison to the methanol solutions. In particular for isotretinoin, a residual concentration of 75% was still present after a light irradiance versus a residual value of just 16% measured at the same time in methanol solution. Further, degradation kinetic parameters of isotretinoin-loaded microemulsion formulation were demonstrated increase isotretinoin half-life about five-times in comparison with a methanol solution under a direct sun light. PMID:22389863

Retinoid quantification by HPLC/MS(n)

NASA Technical Reports Server (NTRS)

McCaffery, Peter; Evans, James; Koul, Omanand; Volpert, Amy; Reid, Kevin; Ullman, M. David

2002-01-01

Retinoic acid (RA) mediates most of the biological effects of vitamin A that are essential for vertebrate survival. It acts through binding to receptors that belong to the nuclear receptor transcription factor superfamily (Mangelsdorf et al. 1994). It is also a highly potent vertebrate teratogen. To determine the function and effects of endogenous and exogenous RA, it is important to have a highly specific, sensitive, accurate, and precise analytical procedure. Current analyses of RA and other retinoids are labor intensive, of poor sensitivity, have limited specificity, or require compatibility with RA reporter cell lines (Chen et al. 1995. BIOCHEM: Pharmacol. 50: 1257-1264; Creech Kraft et al. 1994. BIOCHEM: J. 301: 111-119; Lanvers et al. 1996. J. Chromatogr. B Biomed. Appl. 685: 233-240; Maden et al. 1998. DEVELOPMENT: 125: 4133-4144; Wagner et al. 1992. DEVELOPMENT: 116: 55-66). This paper describes an HPLC/mass spectrometry/mass spectrometry product ion scan (HPLC/MS(n)) procedure for the analysis of retinoids that employs atmospheric pressure chemical ionization MS. The retinoids are separated by normal-phase column chromatography with a linear hexane-isopropanol-dioxane gradient. Each retinoid is detected by a unique series of MS(n) functions set at optimal collision-induced dissociation energy (30% to 32%) for all MS(n) steps. The scan events are divided into three segments, based on HPLC elution order, to maximize the mass spectrometer duty cycle. The all-trans, 9-cis, and 13-cis RA isomers are separated, if desired, by an isocratic hexane-dioxane-isopropanol mobile phase. This paper describes an HPLC/MS(n) procedure possessing high sensitivity and specificity for retinoids.

The role of retinoic acid in the morphogenesis of the neural tube.

PubMed

Wilson, L; Gale, E; Maden, M

2003-10-01

We have examined the role of the signalling molecule, retinoic acid, in the process of neurulation and the subsequent growth and differentiation of the central nervous system using quail embryos that have developed in the absence of retinoic acid. Such retinoic acid-free embryos undergo abnormal neural tube formation in terms of its shape and structure, but the embryos do not display spina bifida or exencephaly. The neural tubes have a wider floor plate, a thicker roof plate and a different dorsoventral shape. Phalloidin staining and electron microscopy revealed alterations in the actin filaments and the junctional complexes of the cell layer lining the lumen. Initially the neural tubes proliferated at the same rate as normal, but later the proliferation rate declined drastically and neuronal differentiation was highly deficient. There were very few motoneurons extending neurites into the periphery, and within the neural tube axon trajectories were chaotic. These results reveal several functions for retinoic acid in the morphogenesis and growth of the neural tube, many of which can be explained by defective notochord signalling, but they do not suggest that this molecule plays a role in neural tube closure.

Stereocontrolled syntheses of the nemorensic acids using 6-diazoheptane-2,5-dione in carbonyl ylide cycloadditions.

PubMed

Hodgson, David M; Le Strat, Frédéric; Avery, Thomas D; Donohue, Andrew C; Brückl, Tobias

2004-12-10

Levulinic acid-derived 6-diazoheptane-2,5-dione (9) serves as a common precursor in a formal synthesis of frontalin 19, and in syntheses of cis-nemorensic acid 1, 4-hydroxy-cis-nemorensic acid 2, 3-hydroxy-cis-nemorensic acid 3, and nemorensic acid 4. The key step in these syntheses is the Rh(2)(OAc)(4)-catalyzed tandem carbonyl ylide formation-intermolecular 1,3-dipolar cycloadditions of diazodione 9 with formaldehyde, alkynes or allene, which occur with high regioselectivity. Subsequent oxidative cleavage of the ring originally derived from the cyclic carbonyl ylide intermediate provides a straightforward access to polysubstituted tetrahydrofurans, and in particular an efficient entry to the nemorensic acids. Enantioselective cycloadditions with diazodione 9, using chiral rhodium catalysts, gave cycloadducts in up to 51% ee.

Determination of Membrane Protein Structure by Rotational Resonance NMR: Bacteriorhodopsin

NASA Astrophysics Data System (ADS)

Creuzet, F.; McDermott, A.; Gebhard, R.; van der Hoef, K.; Spijker-Assink, M. B.; Herzfeld, J.; Lugtenburg, J.; Levitt, M. H.; Griffin, R. G.

1991-02-01

Rotationally resonant magnetization exchange, a new nuclear magnetic resonance (NMR) technique for measuring internuclear distances between like spins in solids, was used to determine the distance between the C-8 and C-18 carbons of retinal in two model compounds and in the membrane protein bacteriorhodopsin. Magnetization transfer between inequivalent spins with an isotropic shift separation, δ, is driven by magic angle spinning at a speed ω_r that matches the rotational resonance condition δ = nω_r, where n is a small integer. The distances measured in this way for both the 6-s-cis- and 6-s-trans-retinoic acid model compounds agreed well with crystallographically known distances. In bacteriorhodopsin the exchange trajectory between C-8 and C-18 was in good agreement with the internuclear distance for a 6-s-trans configuration [4.2 angstroms (overset{circ}{mathrm A})] and inconsistent with that for a 6-s-cis configuration (3.1 overset{circ}{mathrm A}). The results illustrate that rotational resonance can be used for structural studies in membrane proteins and in other situations where diffraction and solution NMR techniques yield limited information.

Monitoring of isotretinoin therapy by measuring the plasma levels of isotretinoin and 4-oxo-isotretinoin. A useful tool for management of severe acne.

PubMed

Almond-Roesler, B; Blume-Peytavi, U; Bisson, S; Krahn, M; Rohloff, E; Orfanos, C E

1998-01-01

Isotretinoin for oral therapy in severe acne conglobata and acne nodulocystica represents a significant achievement; however, the drug exerts several mucocutaneous and systemic adverse effects, besides its teratogenic potency. The aim of this study was to investigate the plasma levels of isotretinoin and of 4-oxo-isotretinoin over long-term treatment of severe acne and to assess any correlation with the given dose, the clinical improvement and the occurrence of side effects. Forty-one patients with severe acne and acne-related disorders were studied under long-term oral intake of isotretinoin. Therapeutic effects and side effects were evaluated prior, during and at the end of therapy. The plasma levels of isotretinoin and of its major metabolite 4-oxo-isotretinoin were measured by reversed-phase HPLC and were correlated with the administered oral dose and the number and frequency of side effects. Dose-dependent plasma levels of isotretinoin and its metabolite were observed. At a mean dosage of 0.75-1.0 mg/kg/day, 404 +/- 142 ng/ml were measured, whereas the plasma levels of 4-oxo-isotretinoin were 1-2x higher. The plasma levels correlated well with the orally administered dose of isotretinoin and the observed mucocutaneous side effects. The study demonstrates that measuring of the plasma levels may be a helpful tool to monitor the individual therapeutic dose regimen in patients with severe acne in order to minimize undesired side effects and to control oral intake.

Can transforming growth factor-beta1 and retinoids modify the activity of estradiol and antiestrogens in MCF-7 breast cancer cells?.

PubMed

Czeczuga-Semeniuk, Ewa; Anchim, Tomasz; Dziecioł, Janusz; Dabrowska, Milena; Wołczyński, Sławomir

2004-01-01

Retinoic acid and transforming growth factor-beta (TGF-beta) affect differentiation, proliferation and carcinogenesis of epithelial cells. The effect of both compounds on the proliferation of cells of the hormone sensitive human breast cancer cell line (ER+) MCF-7 was assessed in the presence of estradiol and tamoxifen. The assay was based on [3H]thymidine incorporation and the proliferative activity of PCNA- and Ki 67-positive cells. The apoptotic index and expression of the Bcl-2 and p53 antigens in MCF-7 cells were also determined. Exogenous TGF-beta1 added to the cell culture showed antiproliferative activity within the concentration range of 0.003-30 ng/ml. Irrespective of TGF-beta1 concentrations, a marked reduction in the stimulatory action of estradiol (10(-9) and 10(-8) M) was observed whereas in combination with tamoxifen (10(-7) and 10(-6) M) only 30 ng/ml TGF-beta1 caused a statistically significant reduction to approximately 30% of the proliferative cells. In further experiments we examined the effect of exposure of breast cancer cells to retinoids in combination with TGF-beta1. The incorporation of [3H]thymidine into MCF-7 cells was inhibited to 52 +/- 19% (control =100%) by 3 ng/ml TGF-beta1, and this dose was used throughout. It was found that addition of TGF-beta1 and isotretinoin to the culture did not decrease proliferation, while TGF-beta1 and tretinoin at low concentrations (3 x 10(-8) and 3 x 10(-7) M) reduced the percentage of proliferating cells by approximately 30% (67+/-8% and 67+/-5%, P<0.05 compared to values in the tretinoin group). Both retinoids also led to a statistically significant decrease in the stimulatory effect of 10(-9) M estradiol, attenuated by TGF-beta1. In addition, the retinoids in combination with TGF-beta1 and tamoxifen (10(-6) M) caused a further reduction in the percentage of proliferating cells. Immunocytochemical analysis showed that all the examined compounds gave a statistically significant reduction in the percentage of cells with a positive reaction to PCNA and Ki 67 antigen. TGF-beta1, isotretinoin and tretinoin added to the culture resulted in the lowest percentage of PCNA positive cells. However, the lowest fraction of Ki 67 positive cells was observed after addition of isotretinoin. The obtained results also confirm the fact that the well-known regulatory proteins Bcl-2 and p53 play an important role in the regulation of apoptosis in the MCF-7 cell line, with lowered Bcl-2 expression accompanying easier apoptotic induction. The majority of the examined compounds act via the p53 pathway although some bypass this important proapoptotic factor.

Thermodynamics of the clusterization process of cis isomers of unsaturated fatty acids at the air/water interface.

PubMed

Vysotsky, Yu B; Belyaeva, E A; Fainerman, V B; Vollhardt, D; Aksenenko, E V; Miller, R

2009-04-02

In the framework of the semiempirical PM3 method, the thermodynamic parameters of cis isomers of unsaturated carboxylic acids at the air/water interface are studied. The model systems used are unsaturated cis fatty acid of the composition Delta = 12-15 and omega = 6-11, where Delta and omega refer to the number of carbon atoms between the functional group and double bond, and that between the double bond and methyl group, respectively. For dimers, trimers, and tetramers of the four acid series, the thermodynamic parameters of clusterization are calculated. It is shown that the position of the double bond does not significantly affect the values of thermodynamic parameters of formation and clusterization of carboxylic acids for equal chain lengths (n = Delta + omega). The calculated results show that for cis unsaturated fatty acid with odd Delta values the spontaneous clusterization threshold corresponds to n = 17-18 carbon atoms in the alkyl chain, while for monounsaturated acids with even Delta values this threshold corresponds to n = 18-19 carbon atoms in the alkyl chain. These differences in the clusterization threshold between the acids with even and odd Delta values are attributed to the formation of additional intermolecular hydrogen bonds between the ketonic oxygen atom of one monomer and the hydrogen atom linked to the alpha-carbon atom of the second monomer for the acids with odd Delta values or between the hydroxyl oxygen atom of one monomer and hydrogen atom linked to the alpha-carbon atom of the second monomer for the acids with even Delta values. The results obtained in the study agree satisfactorily with our experimental data for cis unsaturated nervonic (Delta15, omega9) and erucic acids (Delta13, omega9), and published data for some fatty acids, namely cis-16-heptadecenoic (Delta16, omega1), cis-9-hexadecenoic (Delta7, omega9), cis-11-eicosenoic (Delta11, omega9) and cis-9-octadecenoic acid (Delta9, omega9).

Retinoic acid induces proteasome-dependent degradation of retinoic acid receptor α (RARα) and oncogenic RARα fusion proteins

PubMed Central

Zhu, Jun; Gianni, Maurizio; Kopf, Eliezer; Honoré, Nicole; Chelbi-Alix, Mounira; Koken, Marcel; Quignon, Frédérique; Rochette-Egly, Cécile; de Thé, Hugues

1999-01-01

Analyzing the pathways by which retinoic acid (RA) induces promyelocytic leukemia/retinoic acid receptor α (PML/RARα) catabolism in acute promyelocytic leukemia (APL), we found that, in addition to caspase-mediated PML/RARα cleavage, RA triggers degradation of both PML/RARα and RARα. Similarly, in non-APL cells, RA directly targeted RARα and RARα fusions to the proteasome degradation pathway. Activation of either RARα or RXRα by specific agonists induced degradation of both proteins. Conversely, a mutation in RARα that abolishes heterodimer formation and DNA binding, blocked both RARα and RXRα degradation. Mutations in the RARα DNA-binding domain or AF-2 transcriptional activation region also impaired RARα catabolism. Hence, our results link transcriptional activation to receptor catabolism and suggest that transcriptional up-regulation of nuclear receptors by their ligands may be a feedback mechanism allowing sustained target-gene activation. PMID:10611294

Comparison of efficacy of chemical peeling with 25% trichloroacetic acid and 0.1% retinoic acid for facial rejuvenation.

PubMed

Yildirim, Selda; Gurel, Mehmet Salih; Gungor, Sule; Tekeli, Omur; Canat, Dilek

2016-06-01

Skin aging is a problem which negatively affects the psyche of the person, social relations, as well as work life and health and which compels the patients to find appropriate treatment methods. Numerous treatment methods have been developed in order to delay aging and to reduce the aging effects in addition to having a younger, healthier and more beautiful facial appearance. To compare the efficiency, cosmetic results and possible adverse effects of the peeling treatment with 25% trichloroacetic acid (TCA) and 0.1% retinoic acid for facial rejuvenation in patients presenting with skin aging. Fifty female patients in total presenting with medium and advanced degree skin aging were subject to this study. Two separate treatment groups were formed; the first group underwent chemical skin treatment with 25% TCA while the other group was applied with 0.1% retinoic acid treatment. Following the 4 months' treatment the patients were controlled three times in total for post lesional hypopigmentation, hyperpigmentation, scars, skin irritation and other possible changes per month. The pretreatment and first follow-up visit, and final control images were comparatively evaluated by three observers via specific software. The healing rates of the group subject to retinoic acid were statistically higher (p < 0.05) compared to patients in the TCA group in the final follow-up visit following the treatment according to the first and second observers. On the other hand, according to the third observer, patients applied with retinoic acid presented with higher healing rates compared to those treated with TCA, however; this rate was not statistically significant (p > 0.05). The frequency of TCA- and retinoic acid-associated adverse effects was similar in both groups (p > 0.05). As a result of both treatments, a reduction in the quality of life scores as well as a pronounced recovery (p = 0.001) in the quality of life of those patients with skin aging was observed. The photo aging treatment option with 0.1% retinoic acid is cheaper and more feasible for patients compared to 25% TCA, and it is also as reliable and effective as TCA.

Comparison of efficacy of chemical peeling with 25% trichloroacetic acid and 0.1% retinoic acid for facial rejuvenation

PubMed Central

Gurel, Mehmet Salih; Gungor, Sule; Tekeli, Omur; Canat, Dilek

2016-01-01

Introduction Skin aging is a problem which negatively affects the psyche of the person, social relations, as well as work life and health and which compels the patients to find appropriate treatment methods. Numerous treatment methods have been developed in order to delay aging and to reduce the aging effects in addition to having a younger, healthier and more beautiful facial appearance. Aim To compare the efficiency, cosmetic results and possible adverse effects of the peeling treatment with 25% trichloroacetic acid (TCA) and 0.1% retinoic acid for facial rejuvenation in patients presenting with skin aging. Material and methods Fifty female patients in total presenting with medium and advanced degree skin aging were subject to this study. Two separate treatment groups were formed; the first group underwent chemical skin treatment with 25% TCA while the other group was applied with 0.1% retinoic acid treatment. Following the 4 months’ treatment the patients were controlled three times in total for post lesional hypopigmentation, hyperpigmentation, scars, skin irritation and other possible changes per month. The pretreatment and first follow-up visit, and final control images were comparatively evaluated by three observers via specific software. Results The healing rates of the group subject to retinoic acid were statistically higher (p < 0.05) compared to patients in the TCA group in the final follow-up visit following the treatment according to the first and second observers. On the other hand, according to the third observer, patients applied with retinoic acid presented with higher healing rates compared to those treated with TCA, however; this rate was not statistically significant (p > 0.05). The frequency of TCA- and retinoic acid-associated adverse effects was similar in both groups (p > 0.05). As a result of both treatments, a reduction in the quality of life scores as well as a pronounced recovery (p = 0.001) in the quality of life of those patients with skin aging was observed. Conclusions The photo aging treatment option with 0.1% retinoic acid is cheaper and more feasible for patients compared to 25% TCA, and it is also as reliable and effective as TCA. PMID:27512355

Novel Mechanism of Fatty Acid Sensing in Enteroendocrine Cells: Specific Structures in Oxo-Fatty Acids Produced by Gut Bacteria are Responsible for CCK Secretion in STC-1 Cells via GPR40.

PubMed

Hira, Tohru; Ogasawara, Shono; Yahagi, Asuka; Kamachi, Minami; Li, Jiaxin; Nishimura, Saki; Sakaino, Masayoshi; Yamashita, Takatoshi; Kishino, Shigenobu; Ogawa, Jun; Hara, Hiroshi

2018-06-25

The secretion of gut hormones, such as cholecystokinin (CCK) is stimulated by fatty acids. Although a chain length-dependent mechanism has been proposed, other structural relationships to releasing activity remain unclear. We aimed to elucidate specific structures in fatty acids that are responsible for their CCK-releasing activity, and related sensing mechanisms in enteroendocrine cells. We examined CCK secretory activities in a murine CCK-producing cell line STC-1 by exposing the cells to various modified fatty acids produced by gut lactic acid bacteria. The effects of fatty acids on gastric emptying rate as a CCK-mediated function were examined using acetaminophen- and phenol red-methods in rats. Out of more than thirty octadecanoic (C18)-derived fatty acids tested, five oxo-fatty acids potently stimulated CCK secretion without cytotoxic effects in STC-1 cells. Three fatty acids had a distinct specific structure containing one double-bond, whereas the other two had two double-bonds, nearby an oxo residue. CCK secretion induced by representative fatty acids (10-oxo-trans-11-18:1 and 13-oxo-cis-9,cis-15-18:2) was attenuated by a fatty acid-receptor GPR40 antagonist. Oral administration of 13-oxo-cis-9,cis-15-18:2 lowered the gastric emptying rate in rats in a dose- and structure-dependent manner. These results revealed a novel fatty acid-sensing mechanism in enteroendocrine cells. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

PREDICTING RETINOID RECEPTOR BINDING AFFINITY: COREPA-M APPLICATION

EPA Science Inventory

Retinoic acid and associated vitamin A derivatives comprise a class of endogenous hormones that activate different retinoic acid receptors RARs). Transcriptional events subsequent to this activation are key to controlling several aspects of vertebrate development. As such, identi...

Development of a gas chromatography method for the determination of isotretinoin and its degradation products in pharmaceuticals.

PubMed

Lima, Eliana Martins; Diniz, Danielle G Almeida; Antoniosi-Filho, Nelson R

2005-07-15

This paper describes the development of a gas chromatography (GC) method used for the assay of isotretinoin in its isolated form and in pharmaceutical formulations. Isotretinoin soft and hard gelatin capsules were prepared with various excipients. The performance of the proposed gas chromatography method was compared to that of traditional high performance liquid chromatography (HPLC) systems for this substance, and the GC parameters were established based on several preliminary tests, including thermal analysis of isotretinoin. Results showed that gas chromatography-flame ionization detector (GC-FID) exhibited a separation efficiency superior to that of HPLC, particularly for separating isotretinoin degradation products. This method was proven to be effectively applicable to stability evaluation assays of isotretinoin and isotretinoin based pharmaceuticals.

Clindamycin phosphate/tretinoin gel formulation in the treatment of acne vulgaris.

PubMed

Abdel-Naser, M Badawy; Zouboulis, C C

2008-11-01

Clindamycin phosphate 1.2% together with tretinoin 0.025% as a gel (CTG) is a topical formulation of a fixed and stable combination approved by the FDA for the treatment of acne vulgaris in patients 12 years of age or older. The main indication of CTG is the management of moderate comedonal and mild-to-moderate papulopustular acne, an acne form which is present in more than 50% of acne patients. CTG can also be combined with systemic antiacne therapy, such as systemic isotretinoin, in nodulocystic acne. The product combines the anti-inflammatory and antibacterial properties of clindamycin with the well proven and beneficial comedolytic and anticomedogenic effects of tretinoin (all-trans retinoic acid). The addition of clindamycin to tretinoin enhances the comedolytic efficacy of tretinoin in moderate-to-severe acne of the face. The comedolytic activity of tretinoin and the anti-inflammatory efficacy of clindamycin accelerate resolution of all types of acne lesions without affecting the safety of both compounds. Discontinuation rates due to adverse events related to this formulation were found to be low (

Retinoic Acid Signaling Affects Cortical Synchrony During Sleep

NASA Astrophysics Data System (ADS)

Maret, Stéphanie; Franken, Paul; Dauvilliers, Yves; Ghyselinck, Norbert B.; Chambon, Pierre; Tafti, Mehdi

2005-10-01

Delta oscillations, characteristic of the electroencephalogram (EEG) of slow wave sleep, estimate sleep depth and need and are thought to be closely linked to the recovery function of sleep. The cellular mechanisms underlying the generation of delta waves at the cortical and thalamic levels are well documented, but the molecular regulatory mechanisms remain elusive. Here we demonstrate in the mouse that the gene encoding the retinoic acid receptor beta determines the contribution of delta oscillations to the sleep EEG. Thus, retinoic acid signaling, which is involved in the patterning of the brain and dopaminergic pathways, regulates cortical synchrony in the adult.

Prescriptive contraceptive use among isotretinoin users in the Netherlands in comparison with non-users: a drug utilisation study.

PubMed

Crijns, Hubertina J M J; van Rein, Nienke; Gispen-de Wied, Christine C; Straus, Sabine M; de Jong-van den Berg, Lolkje T W

2012-10-01

To assess the compliance with the isotretinoin Pregnancy Prevention Programme (PPP) by evaluating the use of prescribed contraceptives among isotretinoin users. The PPP contains a requirement for the use of contraceptive methods for women of childbearing potential. A drug utilisation study was performed using data from a drug prescription database (containing Dutch community pharmacy data) covering a population of 500 000 patients. Contraceptive use in female isotretinoin users and in a reference group of female non-isotretinoin users (aged 15-49 years) was compared using data from 1999 until 2006 in 2-year periods. Descriptive statistics were used. Of the female isotretinoin users (n = 651), 52%-54% filled prescriptions on contraceptives in strict accordance to the PPP, used before, during, and after discontinuation of isotretinoin, compared with 39%-46% in the reference group. A more liberal approach of a minimum of one prescription for a contraceptive method showed 61%-64% use of contraceptives among isotretinoin users. Similar patterns were seen when data were broken down in age groups. Furthermore, a higher proportion of female patients using isotretinoin prescribed by general practitioners used prescribed contraceptives compared with those receiving isotretinoin by specialists. Compliance with the contraceptive use according to a PPP for a teratogenic drug such as isotretinoin is 52%-64%, which is lower than anticipated. Reasons for the low compliance will need to be clarified before further measures can be taken. Copyright © 2012 John Wiley & Sons, Ltd.

Occurrence of pregnancy and pregnancy outcomes during isotretinoin therapy.

PubMed

Henry, David; Dormuth, Colin; Winquist, Brandace; Carney, Greg; Bugden, Shawn; Teare, Gary; Lévesque, Linda E; Bérard, Anick; Paterson, J Michael; Platt, Robert W

2016-07-12

Isotretinoin, a teratogen, is widely used to treat cystic acne. Although the risks of pregnancy during isotretinoin therapy are well recognized, there are doubts about the level of adherence with the pregnancy prevention program in Canada. Our objective was to evaluate the effectiveness of the Canadian pregnancy prevention program in 4 provinces: British Columbia, Saskatchewan, Manitoba and Ontario. Using administrative data, we identified 4 historical cohorts of female users of isotretinoin (aged 12-48 yr) for the period 1996 to 2011. We defined pregnancy using International Statistical Classification of Diseases and billing codes. One definition included only cases with documented pregnancy outcomes (high-specificity definition); the other definition also included individuals recorded as receiving prenatal care (high-sensitivity definition). We studied new courses of isotretinoin and detected pregnancies in 2 time windows: during isotretinoin treatment only and up to 42 weeks after treatment. Live births were followed for 1 year to identify congenital malformations. A total of 59 271 female patients received 102 308 courses of isotretinoin. Between 24.3% and 32.9% of participants received prescriptions for oral contraceptives while they were taking isotretinoin, compared with 28.3% to 35.9% in the 12 months before isotretinoin was started. According to the high-specificity definition of pregnancy, there were 186 pregnancies during isotretinoin treatment (3.1/1000 isotretinoin users), compared with 367 (6.2/1000 users) according to the high-sensitivity definition. By 42 weeks after treatment, there were 1473 pregnancies (24.9/1000 users), according to the high-specificity definition. Of these, 1331 (90.4%) terminated spontaneously or were terminated by medical intervention. Among the 118 live births were 11 (9.3%) cases of congenital malformation. Pregnancy rates during isotretinoin treatment remained constant between 1996 and 2011. Adherence to the isotretinoin pregnancy prevention program in Canada was poor during the 15-year period of this study. © 2016 Canadian Medical Association or its licensors.

Occurrence of pregnancy and pregnancy outcomes during isotretinoin therapy

PubMed Central

Henry, David; Dormuth, Colin; Winquist, Brandace; Carney, Greg; Bugden, Shawn; Teare, Gary; Lévesque, Linda E.; Bérard, Anick; Paterson, J. Michael; Platt, Robert W.

2016-01-01

Background: Isotretinoin, a teratogen, is widely used to treat cystic acne. Although the risks of pregnancy during isotretinoin therapy are well recognized, there are doubts about the level of adherence with the pregnancy prevention program in Canada. Our objective was to evaluate the effectiveness of the Canadian pregnancy prevention program in 4 provinces: British Columbia, Saskatchewan, Manitoba and Ontario. Methods: Using administrative data, we identified 4 historical cohorts of female users of isotretinoin (aged 12–48 yr) for the period 1996 to 2011. We defined pregnancy using International Statistical Classification of Diseases and billing codes. One definition included only cases with documented pregnancy outcomes (high-specificity definition); the other definition also included individuals recorded as receiving prenatal care (high-sensitivity definition). We studied new courses of isotretinoin and detected pregnancies in 2 time windows: during isotretinoin treatment only and up to 42 weeks after treatment. Live births were followed for 1 year to identify congenital malformations. Results: A total of 59 271 female patients received 102 308 courses of isotretinoin. Between 24.3% and 32.9% of participants received prescriptions for oral contraceptives while they were taking isotretinoin, compared with 28.3% to 35.9% in the 12 months before isotretinoin was started. According to the high-specificity definition of pregnancy, there were 186 pregnancies during isotretinoin treatment (3.1/1000 isotretinoin users), compared with 367 (6.2/1000 users) according to the high-sensitivity definition. By 42 weeks after treatment, there were 1473 pregnancies (24.9/1000 users), according to the high-specificity definition. Of these, 1331 (90.4%) terminated spontaneously or were terminated by medical intervention. Among the 118 live births were 11 (9.3%) cases of congenital malformation. Pregnancy rates during isotretinoin treatment remained constant between 1996 and 2011. Interpretation: Adherence to the isotretinoin pregnancy prevention program in Canada was poor during the 15-year period of this study. PMID:27114489

BIOCONCENTRATION AND METABOLISM OF ALL-TRANS RETINOIC ACID BY RANA SYLVATICA AND RANA CLAMITANS TADPOLES

EPA Science Inventory

Retinoids, which are Vitamin A derivatives, are important signaling molecules that regulate processes critical for development in all vertebrates. The objective of our study was to examine uptake and metabolism of all-trans retinoic acid...

Reversible effect of all-trans-retinoic acid on AML12 hepatocyte proliferation and cell cycle progression

EPA Science Inventory

The role of all-trans-retinoic acid (atRA) in the regulation of cellular proliferation and differentiation is well documented. Numerous studies have established the cancer preventive propertiesofatRAwhichfunctionstoregulate levels ofcellcycleproteinsessentialfortheGliS transition...

All-trans-retinoic acid inhibits collapsin response mediator protein-2 transcriptional activity during SH-SY5Y neuroblastoma cell differentiation.

PubMed

Fontán-Gabás, Lorena; Oliemuller, Erik; Martínez-Irujo, Juan José; de Miguel, Carlos; Rouzaut, Ana

2007-01-01

Neurons are highly polarized cells composed of two structurally and functionally distinct parts, the axon and the dendrite. The establishment of this asymmetric structure is a tightly regulated process. In fact, alterations in the proteins involved in the configuration of the microtubule lattice are frequent in neuro-oncologic diseases. One of these cytoplasmic mediators is the protein known as collapsin response mediator protein-2, which interacts with and promotes tubulin polymerization. In this study, we investigated collapsin response mediator protein-2 transcriptional regulation during all-trans-retinoic acid-induced differentiation of SH-SY5Y neuroblastoma cells. All-trans-retinoic acid is considered to be a potential preventive and therapeutic agent, and has been extensively used to differentiate neuroblastoma cells in vitro. Therefore, we first demonstrated that collapsin response mediator protein-2 mRNA levels are downregulated during the differentiation process. After completion of deletion construct analysis and mutagenesis and mobility shift assays, we concluded that collapsin response mediator protein-2 basal promoter activity is regulated by the transcription factors AP-2 and Pax-3, whereas E2F, Sp1 and NeuroD1 seem not to participate in its regulation. Furthermore, we finally established that reduced expression of collapsin response mediator protein-2 after all-trans-retinoic acid exposure is associated with impaired Pax-3 and AP-2 binding to their consensus sequences in the collapsin response mediator protein-2 promoter. Decreased attachment of AP-2 is a consequence of its accumulation in the cytoplasm. On the other hand, Pax-3 shows lower binding due to all-trans-retinoic acid-mediated transcriptional repression. Unraveling the molecular mechanisms behind the action of all-trans-retinoic acid on neuroblastoma cells may well offer new perspectives for its clinical application.

Heterodimeric BMP-2/7 Antagonizes the Inhibition of All-Trans Retinoic Acid and Promotes the Osteoblastogenesis

PubMed Central

Bi, Wenjuan; Gu, Zhiyuan; Zheng, Yuanna; Zhang, Xiao; Guo, Jing; Wu, Gang

2013-01-01

Objectives Hypervitaminosis A and alcoholism can result in a low mineral density and compromised regenerative capacity of bone, thus delaying implant osteointegration. The inhibitory effect of all-trans retinoic acid on osteoblastogenesis is considered to be one of the mechanisms. We hypothesized that heterodimeric bone morphogenetic protein-2/7 could antagonize all-trans retinoic acid and enhance osteoblastogenesis, with an aim to accelerate and enhance bone regeneration and implant osteointegration. Materials and Methods We applied 5 ng/ml or 50 ng/ml bone morphogenetic protein-2/7 to restore the osteoblastogenesis of pre-osteoblasts (MC3T3-E1 cell line) that was inhibited by 1 µM all-trans retinoic acid. We evaluated the efficacy by assessing cell numbers (proliferation), alkaline phosphatase activity (a marker for early differentiation), osteocalcin (a marker for late differentiation), calcium deposition (a marker for final mineralization) and the expression of osteoblastogenic genes (such as Runx2, Collagen Ia, alkaline phosphatase and osteocalcin) at different time points. Results All-trans retinoic acid significantly inhibited the expression of all the tested osteoblastogenic genes and proteins except alkaline phosphatase activity. In the presence of ATRA, 50 ng/ml bone morphogenetic protein-2/7 not only completely restored but also significantly enhanced all the osteoblastogenic genes and proteins. On the 28th day, mineralization was completely inhibited by all-trans retinoic acid. In contrast, 50 ng/ml BMP-2/7 could antagonize ATRA and significantly enhance the mineralization about 2.5 folds in comparison with the control treatment (no ATRA, no BMP2/7). Conclusions Heterodimeric bone morphogenetic protein-2/7 bears a promising application potential to significantly promote bone regeneration and implant osteointegration for the patients with hypervitaminosis A and alcoholism. PMID:24205156

Rescue of Hypovitaminosis A Induces Non-Amyloidogenic Amyloid Precursor Protein (APP) Processing.

PubMed

Reinhardt, Sven; Grimm, Marcus O W; Stahlmann, Christoph; Hartmann, Tobias; Shudo, Koichi; Tomita, Taisuke; Endres, Kristina

2016-01-01

Retinoic acid, the bioactive metabolite of beta-carotene or vitamin A, plays a pleiotropic, multifunctional role in vertebrate development. Studies in rodents revealed that a diet deficient in vitamin A results in a complex neonatal syndrome (the VAD syndrome), manifested in many organs. In humans, the function of retinoic acid (RA) extends into adulthood, where it has important roles in fertility, vision, and suppression of neoplastic growth. In recent years, it has also been suggested that retinoic acid might potentially act as a therapeutically relevant drug in attenuating or even preventing neurodegenerative diseases such as Alzheimer's disease (AD). Here, we report that VAD leads to an increase in A-beta peptide levels while only minor effects were observed on expression levels of the amyloid precursor protein (APP) processing proteinases in wild type mice. In line with these findings, rescue of hypovitaminosis reduced A-beta amount to baseline and induced sApp-alpha secretion in combination with an increase of alpha-secretase Adam10. By comparing retinoic acid treatment starting from a full nutrition status and a "VAD" situation in human neuroblastoma cells, we show that while intensities of differential gene expression were higher in replenished cells, a large overlap in AD-related, regulated genes was observed. Our data suggest that hypovitaminosis A can contribute to onset or progression of AD by increasing synthesis of A-beta peptides and that several AD-related genes such as ADAM10 or BDNF are regulated by retinoic acid. We suggest that dietary supplementation with retinoic acid derivatives is likely to have a beneficial effect on AD-pathology in individuals with hypovitaminosis and patients with normal vitamin A status.

Development and Validation of HPLC Method for Determination of Crocetin, a constituent of Saffron, in Human Serum Samples.

PubMed

Mohammadpour, Amir Hooshang; Ramezani, Mohammad; Tavakoli Anaraki, Nasim; Malaekeh-Nikouei, Bizhan; Amel Farzad, Sara; Hosseinzadeh, Hossein

2013-01-01

The present study reports the development and validation of a sensitive and rapid extraction method beside high performance liquid chromatographic method for the determination of crocetin in human serum. The HPLC method was carried out by using a C18 reversed-phase column and a mobile phase composed of methanol/water/acetic acid (85:14.5:0.5 v/v/v) at the flow rate of 0.8 ml/min. The UV detector was set at 423 nm and 13-cis retinoic acid was used as the internal standard. Serum samples were pretreated with solid-phase extraction using Bond Elut C18 (200mg) cartridges or with direct precipitation using acetonitrile. The calibration curves were linear over the range of 0.05-1.25 µg/ml for direct precipitation method and 0.5-5 µg/ml for solid-phase extraction. The mean recoveries of crocetin over a concentration range of 0.05-5 µg/ml serum for direct precipitation method and 0.5-5 µg/ml for solid-phase extraction were above 70 % and 60 %, respectively. The intraday coefficients of variation were 0.37- 2.6% for direct precipitation method and 0.64 - 5.43% for solid-phase extraction. The inter day coefficients of variation were 1.69 - 6.03% for direct precipitation method and 5.13-12.74% for solid-phase extraction, respectively. The lower limit of quantification for crocetin was 0.05 µg/ml for direct precipitation method and 0.5 µg/ml for solid-phase extraction. The validated direct precipitation method for HPLC satisfied all of the criteria that were necessary for a bioanalytical method and could reliably quantitate crocetin in human serum for future clinical pharmacokinetic study.

Development and Validation of HPLC Method for Determination of Crocetin, a constituent of Saffron, in Human Serum Samples

PubMed Central

Mohammadpour, Amir Hooshang; Ramezani, Mohammad; Tavakoli Anaraki, Nasim; Malaekeh-Nikouei, Bizhan; Amel Farzad, Sara; Hosseinzadeh, Hossein

2013-01-01

Objective(s): The present study reports the development and validation of a sensitive and rapid extraction method beside high performance liquid chromatographic method for the determination of crocetin in human serum. Materials and Methods: The HPLC method was carried out by using a C18 reversed-phase column and a mobile phase composed of methanol/water/acetic acid (85:14.5:0.5 v/v/v) at the flow rate of 0.8 ml/min. The UV detector was set at 423 nm and 13-cis retinoic acid was used as the internal standard. Serum samples were pretreated with solid-phase extraction using Bond Elut C18 (200mg) cartridges or with direct precipitation using acetonitrile. Results: The calibration curves were linear over the range of 0.05-1.25 µg/ml for direct precipitation method and 0.5-5 µg/ml for solid-phase extraction. The mean recoveries of crocetin over a concentration range of 0.05-5 µg/ml serum for direct precipitation method and 0.5-5 µg/ml for solid-phase extraction were above 70 % and 60 %, respectively. The intraday coefficients of variation were 0.37- 2.6% for direct precipitation method and 0.64 - 5.43% for solid-phase extraction. The inter day coefficients of variation were 1.69 – 6.03% for direct precipitation method and 5.13-12.74% for solid-phase extraction, respectively. The lower limit of quantification for crocetin was 0.05 µg/ml for direct precipitation method and 0.5 µg/ml for solid-phase extraction. Conclusion: The validated direct precipitation method for HPLC satisfied all of the criteria that were necessary for a bioanalytical method and could reliably quantitate crocetin in human serum for future clinical pharmacokinetic study. PMID:23638292

Cellular fatty acid composition of Erysipelothrix rhusiopathiae and Erysipelothrix tonsillarum.

PubMed

Takahashi, T; Tamura, Y; Endoh, Y S; Hara, N

1994-04-01

The cellular fatty acid compositions in 6 strains of Erysipelothrix rhusiopathiae and 7 strains of Erysipelothrix tonsillarum were determined by gas chromatography. Fatty acids, ranging from C10 to C18, were detected in the test strains. The fatty acid profile was characterized by very high percentages of 18:1 (cis-9) (cis-9-octadecenoic acid; 72.4 to 82.1%) and 16:1 (hexadecenoic acid; 8.7 to 13.7%). The profiles of the E. rhusiopathiae and E. tonsillarum strains resembled each other, indicating that discrimination between E. rhusiopathiae and E. tonsillarum from qualitative or quantitative fatty acid differences is difficult.

Objective assessment of isotretinoin-associated cheilitis: Isotretinoin Cheilitis Grading Scale.

PubMed

Ornelas, Jennifer; Rosamilia, Lorraine; Larsen, Larissa; Foolad, Negar; Wang, Quinlu; Li, Chin-Shang; Sivamani, Raja K

2016-01-01

Isotretinoin remains an effective treatment for severe acne. Despite its effectiveness, it includes many side effects, of which cheilitis is the most common. To develop an objective grading scale for assessment of isotretinoin-associated cheilitis. Cross-sectional clinical grading study. UC Davis Dermatology clinic. Subjects were older than 18 years old and actively treated with oral isotretinoin. Oral Isotretinoin. We developed an Isotretinoin Cheilitis Grading Scale (ICGS) incorporating the following four characteristics: erythema, scale/crust, fissures and inflammation of the commissures. Three board-certified dermatologists independently graded photographs of the subjects. The Kendall's coefficient of concordance (KCC) for the ICGS was 0.88 (p < 0.0001). The Kendall's coefficient was ≥0.72 (p < 0.0001) for each of the four characteristics included in the grading scale. An image-based measurement for lip roughness statistically significantly correlated with the lip scale/crusting assessment (r = 0.52, p < 0.05). The ICGS is reproducible and relatively simple to use. It can be incorporated as an objective tool to aid in the assessment of isotretinoin associated cheilitis.

A randomized trial of the efficacy of a new micronized formulation versus a standard formulation of isotretinoin in patients with severe recalcitrant nodular acne.

PubMed

Strauss, J S; Leyden, J J; Lucky, A W; Lookingbill, D P; Drake, L A; Hanifin, J M; Lowe, N J; Jones, T M; Stewart, D M; Jarratt, M T; Katz, I; Pariser, D M; Pariser, R J; Tschen, E; Chalker, D K; Rafal, E S; Savin, R P; Roth, H L; Chang, L K; Baginski, D J; Kempers, S; McLane, J; Eberhardt, D; Leach, E E; Bryce, G; Hong, J

2001-08-01

Isotretinoin is very frequently the drug of choice for the management of severe recalcitrant nodular acne. Recently, a new micronized and more bioavailable formulation of isotretinoin has been developed that permits once-daily administration in lower doses than usually used with standard isotretinoin (Accutane), regardless of whether it is taken with or without food. Our purpose was to determine whether micronized isotretinoin and standard isotretinoin are clinically equivalent. In this multicenter, double-blind, double-dummy study, 600 patients with severe recalcitrant nodular acne were treated with either 0.4 mg/kg of micronized isotretinoin once daily without food (n = 300) or 1.0 mg/kg per day of standard isotretinoin in two divided doses with food (n = 300). Lesion counts were monitored over 20 weeks. Both treatment groups in this well-controlled clinical trial experienced an equivalent reduction in the number of total nodules (facial plus truncal). In addition, an equivalent proportion of patients achieved 90% clearance of the total number of nodules. Both formulations had similar results for other efficacy variables. Once-daily use of the micronized and more bioavailable formulation of isotretinoin under fasted conditions is clinically equivalent to the standard twice-daily formulation under fed conditions in the treatment of severe recalcitrant nodular acne.

8-CPT-cAMP/all-trans retinoic acid targets t(11;17) acute promyelocytic leukemia through enhanced cell differentiation and PLZF/RARα degradation

PubMed Central

Jiao, Bo; Ren, Zhi-Hong; Liu, Ping; Chen, Li-Juan; Shi, Jing-Yi; Dong, Ying; Ablain, Julien; Shi, Lin; Gao, Li; Hu, Jun-Pei; Ren, Rui-Bao; de Thé, Hugues; Chen, Zhu; Chen, Sai-Juan

2013-01-01

The refractoriness of acute promyelocytic leukemia (APL) with t(11;17)(q23;q21) to all-trans retinoic acid (ATRA)-based therapy concerns clinicians and intrigues basic researchers. By using a murine leukemic model carrying both promyelocytic leukemia zinc finger/retinoic acid receptor-α (PLZF/RARα) and RARα/PLZF fusion genes, we discovered that 8-chlorophenylthio adenosine-3′, 5′-cyclic monophosphate (8-CPT-cAMP) enhances cellular differentiation and improves gene trans-activation by ATRA in leukemic blasts. Mechanistically, in combination with ATRA, 8-CPT-cAMP activates PKA, causing phosphorylation of PLZF/RARα at Ser765 and resulting in increased dissociation of the silencing mediator for retinoic acid and thyroid hormone receptors/nuclear receptor corepressor from PLZF/RARα. This process results in changes of local chromatin and transcriptional reactivation of the retinoic acid pathway in leukemic cells. Meanwhile, 8-CPT-cAMP also potentiated ATRA-induced degradation of PLZF/RARα through its Ser765 phosphorylation. In vivo treatment of the t(11;17) APL mouse model demonstrated that 8-CPT-cAMP could significantly improve the therapeutic effect of ATRA by targeting a leukemia-initiating cell activity. This combined therapy, which induces enhanced differentiation and oncoprotein degradation, may benefit t(11;17) APL patients. PMID:23382200

PKC delta and NADPH oxidase in retinoic acid-induced neuroblastoma cell differentiation.

PubMed

Nitti, Mariapaola; Furfaro, Anna Lisa; Cevasco, Claudia; Traverso, Nicola; Marinari, Umberto Maria; Pronzato, Maria Adelaide; Domenicotti, Cinzia

2010-05-01

The role of reactive oxygen species (ROS) in the regulation of signal transduction processes has been well established in many cell types and recently the fine tuning of redox signalling in neurons received increasing attention. With regard to this, the involvement of NADPH oxidase (NOX) in neuronal pathophysiology has been proposed but deserves more investigation. In the present study, we used SH-SY5Y neuroblastoma cells to analyse the role of NADPH oxidase in retinoic acid (RA)-induced differentiation, pointing out the involvement of protein kinase C (PKC) delta in the activation of NOX. Retinoic acid induces neuronal differentiation as revealed by the increased expression of MAP2, the decreased cell doubling rate, and the gain in neuronal morphological features and these events are accompanied by the increased expression level of PKC delta and p67(phox), one of the components of NADPH oxidase. Using DPI to inhibit NOX activity we show that retinoic acid acts through this enzyme to induce morphological changes linked to the differentiation. Moreover, using rottlerin to inhibit PKC delta or transfection experiments to overexpress it, we show that retinoic acid acts through this enzyme to induce MAP2 expression and to increase p67(phox) membrane translocation leading to NADPH oxidase activation. These findings identify the activation of PKC delta and NADPH oxidase as crucial steps in RA-induced neuroblastoma cell differentiation. 2010 Elsevier Inc. All rights reserved.

ISOLATION AND CHARACTERIZATION OF AXOLOTL NPDC-1 AND ITS EFFECTS ON RETINOIC ACID RECEPTOR SIGNALING

PubMed Central

Theodosiou, Maria; Monaghan, James R; Spencer, Michael L; Voss, S Randal; Noonan, Daniel J

2009-01-01

Retinoic acid, a key morphogen in early vertebrate development and tissue regeneration, mediates its effects through the binding of receptors that act as ligand-induced transcription factors. These binding events function to recruit an array of transcription co-regulatory proteins to specific gene promoters. One such co-regulatory protein, neuronal proliferation and differentiation control-1 (NPDC-1), is broadly expressed during mammalian development and functions as an in vitro repressor of retinoic acid receptor (RAR)-mediated transcription. To obtain comparative and developmental insights about NPDC-1 function, we cloned the axolotl (Ambystoma mexicanum) orthologue and measured transcript abundances among tissues sampled during the embryonic and juvenile phases of development, and also during spinal cord regeneration. Structurally, the axolotl orthologue of NPDC-1 retained sequence identity to mammalian sequences in all functional domains. Functionally, we observed that axolotl NPDC-1 mRNA expression peaked late in embryogenesis, with highest levels of expression occurring during the time of limb development, a process regulated by retinoic acid signaling. Also similar to what has been observed in mammals, axolotl NPDC-1 directly interacts with axolotl RAR, modulates axolotl RAR DNA binding, and represses cell proliferation and axolotl RAR-mediated gene transcription. These data justify axolotl as a model to further investigate NPDC-1 and its role in regulating retinoic acid signaling. PMID:17331771

FOXP2 drives neuronal differentiation by interacting with retinoic acid signaling pathways.

PubMed

Devanna, Paolo; Middelbeek, Jeroen; Vernes, Sonja C

2014-01-01

FOXP2 was the first gene shown to cause a Mendelian form of speech and language disorder. Although developmentally expressed in many organs, loss of a single copy of FOXP2 leads to a phenotype that is largely restricted to orofacial impairment during articulation and linguistic processing deficits. Why perturbed FOXP2 function affects specific aspects of the developing brain remains elusive. We investigated the role of FOXP2 in neuronal differentiation and found that FOXP2 drives molecular changes consistent with neuronal differentiation in a human model system. We identified a network of FOXP2 regulated genes related to retinoic acid signaling and neuronal differentiation. FOXP2 also produced phenotypic changes associated with neuronal differentiation including increased neurite outgrowth and reduced migration. Crucially, cells expressing FOXP2 displayed increased sensitivity to retinoic acid exposure. This suggests a mechanism by which FOXP2 may be able to increase the cellular differentiation response to environmental retinoic acid cues for specific subsets of neurons in the brain. These data demonstrate that FOXP2 promotes neuronal differentiation by interacting with the retinoic acid signaling pathway and regulates key processes required for normal circuit formation such as neuronal migration and neurite outgrowth. In this way, FOXP2, which is found only in specific subpopulations of neurons in the brain, may drive precise neuronal differentiation patterns and/or control localization and connectivity of these FOXP2 positive cells.

FOXP2 drives neuronal differentiation by interacting with retinoic acid signaling pathways

PubMed Central

Devanna, Paolo; Middelbeek, Jeroen; Vernes, Sonja C.

2014-01-01

FOXP2 was the first gene shown to cause a Mendelian form of speech and language disorder. Although developmentally expressed in many organs, loss of a single copy of FOXP2 leads to a phenotype that is largely restricted to orofacial impairment during articulation and linguistic processing deficits. Why perturbed FOXP2 function affects specific aspects of the developing brain remains elusive. We investigated the role of FOXP2 in neuronal differentiation and found that FOXP2 drives molecular changes consistent with neuronal differentiation in a human model system. We identified a network of FOXP2 regulated genes related to retinoic acid signaling and neuronal differentiation. FOXP2 also produced phenotypic changes associated with neuronal differentiation including increased neurite outgrowth and reduced migration. Crucially, cells expressing FOXP2 displayed increased sensitivity to retinoic acid exposure. This suggests a mechanism by which FOXP2 may be able to increase the cellular differentiation response to environmental retinoic acid cues for specific subsets of neurons in the brain. These data demonstrate that FOXP2 promotes neuronal differentiation by interacting with the retinoic acid signaling pathway and regulates key processes required for normal circuit formation such as neuronal migration and neurite outgrowth. In this way, FOXP2, which is found only in specific subpopulations of neurons in the brain, may drive precise neuronal differentiation patterns and/or control localization and connectivity of these FOXP2 positive cells. PMID:25309332

The Effectiveness of a 5% Retinoic Acid Peel Combined with Microdermabrasion for Facial Photoaging: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

PubMed

Faghihi, Gita; Fatemi-Tabaei, Saghi; Abtahi-Naeini, Bahareh; Siadat, Amir Hossein; Sadeghian, Giti; Ali Nilforoushzadeh, Mohammad; Mohamadian-Shoeili, Hamed

2017-01-01

Background . Tretinoin has been shown to improve photoaged skin. This study was designed to evaluate the efficacy and tolerability of a 5% retinoic acid peel combined with microdermabrasion for facial photoaging. Materials and Methods . Forty-five patients, aged 35-70, affected by moderate-to-severe photodamage were enrolled in this trial. All patients received 3 sessions of full facial microdermabrasion and 3 sessions of either 5% retinoic acid peel or placebo after the microdermabrasion. Efficacy was measured using the Glogau scale. Patients were assessed at 2 weeks and 1, 2, and 6 months after treatment initiation. Results . The mean ± SD age of participants was 49.55 ± 11.61 years, and the majorities (73.3%) were female. Between 1 month and 2 months, participants reported slight but statistically significant improvements for all parameters ( P < 0.001). In terms of adverse effects, there were statistically significant differences reported between the 5% retinoic acid peel groups and the control group ( P < 0.001). The majority of adverse effects reported in the study were described as mild and transient. Conclusion . This study demonstrated that 5% retinoic acid peel cream combined with microdermabrasion was safe and effective in the treatment of photoaging in the Iranian population. This trial is registered with IRCT2015121112782N8.

The Effectiveness of a 5% Retinoic Acid Peel Combined with Microdermabrasion for Facial Photoaging: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

PubMed Central

Faghihi, Gita; Siadat, Amir Hossein; Sadeghian, Giti; Ali Nilforoushzadeh, Mohammad; Mohamadian-shoeili, Hamed

2017-01-01

Background. Tretinoin has been shown to improve photoaged skin. This study was designed to evaluate the efficacy and tolerability of a 5% retinoic acid peel combined with microdermabrasion for facial photoaging. Materials and Methods. Forty-five patients, aged 35–70, affected by moderate-to-severe photodamage were enrolled in this trial. All patients received 3 sessions of full facial microdermabrasion and 3 sessions of either 5% retinoic acid peel or placebo after the microdermabrasion. Efficacy was measured using the Glogau scale. Patients were assessed at 2 weeks and 1, 2, and 6 months after treatment initiation. Results. The mean ± SD age of participants was 49.55 ± 11.61 years, and the majorities (73.3%) were female. Between 1 month and 2 months, participants reported slight but statistically significant improvements for all parameters (P < 0.001). In terms of adverse effects, there were statistically significant differences reported between the 5% retinoic acid peel groups and the control group (P < 0.001). The majority of adverse effects reported in the study were described as mild and transient. Conclusion. This study demonstrated that 5% retinoic acid peel cream combined with microdermabrasion was safe and effective in the treatment of photoaging in the Iranian population. This trial is registered with IRCT2015121112782N8. PMID:28293257

Pharmaceutical quality of generic isotretinoin products, compared with Roaccutane.

PubMed

Taylor, Peter W; Keenan, Michael H J

2006-03-01

Isotretinoin is the drug of choice for the management of severe recalcitrant nodular acne. Several generic products are available. However, their pharmaceutical quality, in particular particle size distribution, which may affect safety and efficacy is unknown. Hence, prescribing of some generic products may be problematic. To assess the pharmaceutical quality of 14 generic isotretinoin products compared with Roaccutane (F. Hoffmann-La Roche Ltd). Tests were performed according to Roche standard procedures, European and US pharmacopoeia specifications. Tests included isotretinoin content, identity and amount of impurities and degradation products, effect of accelerated shelf-life studies on stability, particle size distribution and composition of non-active ingredients. The 14 isotretinoin products differed by 30-fold in median particle size and showed variation in their non-active ingredients. The average isotretinoin content of Acnotin and Acne-Tretin fell outside the 95-105% Roche specifications. Following accelerated shelf-life tests, only four products retained isotretinoin content within Roche specifications, whilst Acne-Tretin (the only powder formulation) lost 72.5% isotretinoin content. Two generic products exceeded the +/- 2% specification (Ph. Eur.) and a further three exceeded the +/- 1% (USP) for tretinoin content, eight exceeded the 2.54% specification for total impurities and six contained >or= 5 unknown impurities. Isotretinoin-5.6-epoxide content exceeded the 1.04% specification in five generic products. Thirteen generic products failed to match Roaccutane in one or more tests and 11 failed in three or more tests. It cannot be assumed that all generic isotretinoin products are as therapeutically effective or safe as Roaccutane.

Steady-state pharmacokinetics of isotretinoin and its 4-oxo metabolite: implications for fetal safety.

PubMed

Nulman, I; Berkovitch, M; Klein, J; Pastuszak, A; Lester, R S; Shear, N; Koren, G

1998-10-01

Isotretinoin is the most potent human teratogen on the market. Women for whom contraception fails may conceive during or soon after discontinuing isotretinoin therapy, making its elimination kinetics a crucial determinant of fetal safety. The steady-state pharmacokinetics of isotretinoin and its major 4-oxo metabolite were studied in 16 adult patients treated for acne who were receiving doses that ranged from 0.47 to 1.7 mg/kg daily. This is the first study of the pharmacokinetics of isotretinoin in women of childbearing age (n = 11). The clinical efficacy and tolerability of isotretinoin was investigated, and the correlation between these data and steady-state serum concentrations of isotretinoin was tested. The concentration-time data best fitted a two-compartment open model with linear elimination. There was no correlation between efficacy and tolerability of isotretinoin and steady-state serum concentrations. There was no correlation between dose of isotretinoin and steady-state concentration, due to the large variability in apparent clearance. Values for elimination half-life (t1/2) of isotretinoin and its metabolite were 29+/-40 hours and 22+/-10 hours, respectively. These data suggest a longer elimination t1/2 of the parent drug than previously reported. This is probably due to the longer sampling time used in this study (as long as 28 days). This study suggests that a greater variability exists in the safe time after discontinuation of the drug for onset of conception.

A comparative review of the isotretinoin pregnancy risk management programs across four continents.

PubMed

Kovitwanichkanont, Tom; Driscoll, Tim

2018-03-06

Isotretinoin has revolutionized the treatment of severe acne vulgaris, a condition which if left untreated may result in significant socio-psychological implications for those affected. Timely access to isotretinoin therapy is important to avoid the risks of potential physical and emotional scarring. However, due to its high risks of teratogenicity, isotretinoin must be used with care in females of childbearing potential. Since isotretinoin's introduction, numerous risk management programs have been implemented across the world in an attempt to prevent isotretinoin use in pregnancy. This paper aims to provide an evidence-based review of the risk management programs for isotretinoin in Australia, Europe, Singapore, New Zealand, and the United States of America. The effectiveness of these programs and the factors leading to isotretinoin exposure in pregnancy are critically analyzed in an effort to inform the future direction with respect to designing the ideal regulatory program. Stringent risk management programs, such as the iPLEDGE in the US and Pregnancy Prevention Program (PPP) in Europe, may not be effective in reducing the risks of fetal exposure to isotretinoin when used alone. There is evidence that such strenuous regulation results in increased fear of teratogenic risks but does not translate into a reduced rate of pregnancies exposed to isotretinoin. A successful program must prioritize education about effective contraception, while minimizing any extraneous requirements, to ensure that women are not inadvertently undertreated for acne. © 2018 The International Society of Dermatology.

Assessing the availability of the teratogenic drug isotretinoin outside the pregnancy prevention programme: a survey of e-pharmacies.

PubMed

Lagan, Briege M; Dolk, Helen; White, Bronagh; Uges, Donald R A; Sinclair, M

2014-04-01

The increase in online purchasing of medications raises safety concerns regarding teratogenic drugs. The use of the teratogenic drug 'isotretinoin' for women of childbearing age requires strict adherence to the Pregnancy Prevention Programme (PPP), a risk minimisation measure imposed on prescribers and users. We sought to determine how readily consumers can purchase isotretinoin online and the associated safety procedures and information. A descriptive cross-sectional survey was conducted of 50 e-pharmacies identified from commonly used search engines. E-pharmacy characteristics and isotretinoin PPP specific criteria were evaluated. Purchases of isotretinoin from seven e-pharmacies not bearing authentication logos and not requiring a prescription were assessed for PPP policy adherence, purchasing procedures and compound quality. Forty-three (86%) of the e-pharmacies did not have an authentication seal/logo. Isotretinoin could be purchased from 42 sites without a valid prescription. Information on isotretinoin causing birth defects was lacking in 25 of the 50 sites, on not taking isotretinoin in pregnancy in 24 sites and not taking isotretinoin if planning or at risk of a pregnancy in 33 sites. Of the eight attempted purchases, seven arrived, all without any patient information leaflet. All were verified as isotretinoin. The Internet provides a loophole for purchasing of medications known to cause congenital abnormalities, which needs to be addressed by medicines regulatory agencies worldwide. The current PPP for isotretinoin may be failing to protect mothers and babies from preventable harm-clinicians need to be aware of this, and the public needs to be educated about the potential risks. © 2014 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons, Ltd.

Expression of membrane-bound mucins in human nasal mucosa: different patterns for MUC4 and MUC16.

PubMed

Woo, Hyun-Jae; Bae, Chang Hoon; Song, Si-Youn; Lee, Heung-Man; Kim, Yong-Dae

2010-06-01

To acquire basic information concerning the function of the membrane-bound mucin MUC16 in nasal mucosa compared with the best-characterized membrane-bound mucin, MUC4. In vitro study using semiquantatitive reverse transcription-polymerase chain reaction analysis and immunoassay. Yeungnam University College of Medicine. We examined the nasal polyps obtained during endoscopic sinus surgery in 10 patients, the normal ethmoid sinus mucosa obtained from 10 patients, and human nasal polyp epithelial (HNPE) cells. Gene expression of MUC4 and MUC16 in nasal polyps and normal nasal mucosa. In addition, we evaluated the effect of 4 physiologically relevant agents, including retinoic acid, interleukin 1beta, phorbol 12-myristate 13-acetate (PMA), and dexamethasone, on the expression of MUC4 and MUC16 in HNPE cells at the gene and protein levels. In nasal polyps, MUC4 was upregulated compared with normal nasal mucosa (P = .009), whereas MUC16 expression did not differ between nasal polyps and normal nasal mucosa. Retinoic acid and interleukin 1beta increased MUC4 expression at the gene and protein level in HNPE cells, whereas MUC16 expression was not affected. Unlike retinoic acid and interleukin 1beta, PMA and dexamethasone increased MUC16 expression, whereas they had no significant effect on MUC4 expression. Expression of MUC4 and MUC16 are regulated differently in nasal mucosa. Dexamethasone and PMA are potent mediators for the expression of MUC16 in nasal polyps.

Effects of electroacupuncture and the retinoid X receptor (RXR) signalling pathway on oligodendrocyte differentiation in the demyelinated spinal cord of rats

PubMed Central

Yang, Xiao-Hua; Ding, Ying; Li, Wen; Zhang, Rong-Yi; Wu, Jin-Lang; Ling, Eng-Ang; Wu, Wutian

2017-01-01

Objectives In spinal cord demyelination, some oligodendrocyte precursor cells (OPCs) remain in the demyelinated region but have a reduced capacity to differentiate into oligodendrocytes. This study investigated whether ‘Governor Vessel’ (GV) electroacupuncture (EA) would promote the differentiation of endogenous OPCs into oligodendrocytes by activating the retinoid X receptor γ (RXR-γ)-mediated signalling pathway. Methods Adult rats were microinjected with ethidium bromide (EB) into the T10 spinal cord to establish a model of spinal cord demyelination. EB-injected rats remained untreated (EB group, n=26) or received EA treatment (EB+EA group, n=26). A control group (n=26) was also included that underwent dural exposure without EB injection. After euthanasia at 7 days (n=5 per group), 15 days (n=8 per group) or 30 days (n=13 per group), protein expression of RXR-γ in the demyelinated spinal cord was evaluated by immunohistochemistry and Western blotting. In addition, OPCs derived from rat embryonic spinal cord were cultured in vitro, and exogenous 9-cis-RA (retinoic acid) and RXR-γ antagonist HX531 were administered to determine whether RA could activate RXR-γ and promote OPC differentiation. Results EA was found to increase the numbers of both OPCs and oligodendrocytes expressing RXR-γ and RALDH2, and promote remyelination in the remyelinated spinal cord. Exogenous 9-cis-RA enhanced the differentiation of OPCs into mature oligodendrocytes by activating RXR-γ. Conclusions The results suggest that EA may activate RXR signalling to promote the differentiation of OPCs into oligodendrocytes in spinal cord demyelination. PMID:27841975

EFFECTS OF METHOPRENE DERIVATIVES ON THE EXPRESSION OF RETINOIC ACID SENSITIVE GENES AND PROTEINS IN CULTURED CELLS

EPA Science Inventory

The insect juvenile hormone analog methoprene has been suggested as a possible cause of malformations in frogs and other amphibians. Methoprene has structural similarities to the ubiquitous development regulator, retinoic acid, and thus, may bind to retinoid receptors and consequ...

UPTAKE AND METABOLISM OF ALL-TRANS RETINOIC ACID BY THREE NATIVE NORTH AMERICAN RANIDS

EPA Science Inventory

Retinoids, which are Vvitamin A derivatives, are important signaling molecules that regulate processes critical for development in all vertebrates. The objective of our study was to examine uptake and metabolism of the model retinoid, all-trans retinoic acid (all-trans RA), by th...

DIFFERENTIAL EXPRESSION OF RETINOIC ACID BIOSYNTHETIC AND METABOLISM GENES IN LIVERS FROM MICE TREATED WITH HEPATOTUMORIGENIC AND NON-HEPATOTUMORIGENIC CONAZOLES

EPA Science Inventory

Conazoles are fungicides used in crop protection and as pharmaceuticals. Triadimefon and propiconazole are hepatotumorigenic in mice, while myclobutanil is not. Previous toxicogenomic studies suggest that alteration of the retinoic acid metabolism pathway may play a key event in ...

CHARACTERIZATION OF CYPS IN THE METABOLISM OF ALL TRANS RETINOIC ACID BY LIVER MICROSOMES FROM MICE TREATED WITH CONAZOLES

EPA Science Inventory

Conazoles are fungicides used in crop protection and as pharmaceuticals. Triadimefon and propiconazole are hepatotumorigenic in mice, while myclobutanil is not. Previous toxicogenomic studies suggest that alteration of the retinoic acid metabolism pathway may involve in conazole-...

Autologous stem cell transplantation for the treatment of neuroblastoma in Korea.

PubMed Central

Ryu, Kyung Ha; Ahn, Hyo Seop; Koo, Hong Hoe; Kook, Hoon; Kim, Moon Kyu; Kim, Hack Ki; Ghim, Thad; Moon, Hyung Nam; Seo, Jong Jin; Sung, Ki Woong; Shin, Hee Young; Yoo, Eun Sun; Lyu, Chuhl Joo; Lee, Young Ho; Lee, Hahng; Cho, Bin; Cho, Hyun Sang; Choi, Hyung Soo; Hah, Jeong Ok; Hwang, Tai Ju

2003-01-01

Autologous stem cell transplantation (ASCT) for the treatment of high-risk neuroblastoma (NBL) is an accepted method for restoring bone marrow depression after high dose chemotherapy. We retrospectively analyzed eighty eight cases of NBL that underwent ASCT following marrow ablative therapy at 12 transplant centers of the Korean Society of Pediatric Hematology-Oncology between January 1996 and September 2000. Seventy nine children were of stage IV NBL and 9 were of stage III with N-myc amplification. Various cytoreductive regimens were used. However, the main regimen was 'CEM' consisting of carboplatin, etoposide and melphalan, and this was used in 66 patients. Total body irradiation was also added in 36 patients for myeloablation. To reduce tumor cell contamination, stem cell infusions after CD34+ cell selection were performed in 16 patients. Post-transplantation therapies included the second transplantation in 18 patients, interleukin2 therapy in 45, 13-cis retinoic acid in 40, 131-meta-iodobenzylguanidine in 4, conventional chemotherapy in 11, and local radiotherapy in 8. Twenty two patients died, sixty six patients are surviving 1 to 46 months after ASCT (median followup duration, 14.5 months). Although the follow-up period was short and the number of patients small, we believe that ASCT might improve the survival rate in high-risk NBL. PMID:12692423

Peroxygenase-Catalyzed Fatty Acid Epoxidation in Cereal Seeds (Sequential Oxidation of Linoleic Acid into 9(S),12(S),13(S)-Trihydroxy-10(E)-Octadecenoic Acid).

PubMed Central

Hamberg, M.; Hamberg, G.

1996-01-01

Peroxygenase-catalyzed epoxidation of oleic acid in preparations of cereal seeds was investigated. The 105,000g particle fraction of oat (Avena sativa) seed homogenate showed high peroxygenase activity, i.e. 3034 [plus or minus] 288 and 2441 [plus or minus] 168 nmol (10 min)-1 mg-1 protein in two cultivars, whereas the corresponding fraction obtained from barley (Hordeum vulgare and Hordeum distichum), rye (Secale cereale), and wheat (Triticum aestivum) showed only weak activity, i.e. 13 to 138 nmol (10 min)-1 mg-1 protein. In subcellular fractions of oat seed homogenate, peroxygenase specific activity was highest in the 105,000g particle fraction, whereas lipoxygenase activity was more evenly distributed and highest in the 105,000g supernatant fraction. Incubation of [1-14C]linoleic acid with the 105,000g supernatant of oat seed homogenate led to the formation of several metabolites, i.e. in order of decreasing abundance, 9(S)-hydroxy-10(E),12(Z)-octadecadienoic acid, 9(S),12(S),13(S)-trihydroxy-10(E)-octadecenoic acid, cis-9,10-epoxy-12(Z)-octadecenoic acid [mainly the 9(R),10(S) enantiomer], cis-12,13-epoxy-9(Z)-octadecenoic acid [mainly the 12(R),13(S) enantiomer], threo-12,13-dihydroxy-9(Z)-octadecenoic acid, and 12(R),13(S)-epoxy-9(S)-hydroxy-10(E)-octadecenoic acid. Incubation of linoleic acid with the 105,000g particle fraction gave a similar, but not identical, pattern of metabolites. Conversion of linoleic acid into 9(S),12(S),13(S)-trihydroxy-10(E)-octadecenoic acid, a naturally occurring oxylipin with antifungal properties, took place by a pathway involving sequential catalysis by lipoxygenase, peroxygenase, and epoxide hydrolase. PMID:12226220

Assessing the availability of the teratogenic drug isotretinoin outside the pregnancy prevention programme: a survey of e-pharmacies†

PubMed Central

Lagan, Briege M; Dolk, Helen; White, Bronagh; Uges, Donald R A; Sinclair, M

2014-01-01

Purpose The increase in online purchasing of medications raises safety concerns regarding teratogenic drugs. The use of the teratogenic drug ‘isotretinoin’ for women of childbearing age requires strict adherence to the Pregnancy Prevention Programme (PPP), a risk minimisation measure imposed on prescribers and users. We sought to determine how readily consumers can purchase isotretinoin online and the associated safety procedures and information. Methods A descriptive cross-sectional survey was conducted of 50 e-pharmacies identified from commonly used search engines. E-pharmacy characteristics and isotretinoin PPP specific criteria were evaluated. Purchases of isotretinoin from seven e-pharmacies not bearing authentication logos and not requiring a prescription were assessed for PPP policy adherence, purchasing procedures and compound quality. Results Forty-three (86%) of the e-pharmacies did not have an authentication seal/logo. Isotretinoin could be purchased from 42 sites without a valid prescription. Information on isotretinoin causing birth defects was lacking in 25 of the 50 sites, on not taking isotretinoin in pregnancy in 24 sites and not taking isotretinoin if planning or at risk of a pregnancy in 33 sites. Of the eight attempted purchases, seven arrived, all without any patient information leaflet. All were verified as isotretinoin. Conclusion The Internet provides a loophole for purchasing of medications known to cause congenital abnormalities, which needs to be addressed by medicines regulatory agencies worldwide. The current PPP for isotretinoin may be failing to protect mothers and babies from preventable harm—clinicians need to be aware of this, and the public needs to be educated about the potential risks. PMID:24493556

Isotretinoin revisited: pluripotent effects on human sebaceous gland cells.

PubMed

Zouboulis, Christos C

2006-10-01

Nelson et al. confirmed the previously described antiproliferative effect of isotretinoin on human sebocytes. They attributed a portion of this decrease to cell cycle arrest and detected sebocyte apoptosis, which was not recapitulated by alitretinoin or tretinoin. These events were specific to sebocytes, as isotretinoin failed to induce apoptosis in keratinocytes. Isotretinoin-induced apoptosis was shown to be an RAR-independent mechanism.

Objective Assessment of Isotretinoin-Associated Cheilitis: Isotretinoin Cheilitis Grading Scale

PubMed Central

Ornelas, Jennifer; Rosamilia, Lorraine; Larsen, Larissa; Foolad, Negar; Wang, Quinlu; Li, Chin-Shang; Sivamani, Raja K.

2016-01-01

Importance Isotretinoin remains an effective treatment for severe acne. Despite its effectiveness, it includes many side effects, of which cheilitis is the most common. Objective To develop an objective grading scale for assessment of isotretinoin-associated cheilitis, Design Cross-sectional clinical grading study. Setting UC Davis Dermatology clinic. Participants Subjects were older than 18 years old and actively treated with oral isotretinoin. Exposures Oral Isotretinoin. Main outcomes and Measures We developed an isotretinoin cheilitis grading scale (ICGS) incorporating the following four characteristics: erythema, scale/crust, fissures, and inflammation of the commissures. Three board-certified dermatologists independently graded photographs of the subjects. Results The Kendall’s coefficient of concordance (KCC) for the ICGS was 0.88 (p<0.0001). The Kendall’s coefficient was ≥ 0.72 (p<0.0001) for each of the four characteristics included in the grading scale. An image-based measurement for lip roughness statistically significantly correlated with the lip scale/crusting assessment (r = 0.52, p <0.05). Conclusion and Relevance The ICGS is reproducible and relatively simple to use. It can be incorporated as an objective tool to aid in the assessment of isotretinoin associated cheilitis. PMID:26395167

Retinoid-xenobiotic interactions: the Ying and the Yang

PubMed Central

2015-01-01

The literature provides compelling evidence pointing to tight metabolic interactions between retinoids and xenobiotics. These are extensive and important for understanding xenobiotic actions in the body. Within the body, retinoids affect xenobiotic metabolism and actions and conversely, xenobiotics affect retinoid metabolism and actions. This article summarizes data that establish the importance of retinoid-dependent metabolic pathways for sustaining the body’s responses to xenobiotic exposure, including the roles of all-trans- and 9-cis-retinoic acid for protecting mammals from harmful xenobiotic effects and for ensuring xenobiotic elimination from the body. This review will also consider molecular mechanisms underlying xenobiotic toxicity focusing on how this may contribute to retinoid deficiency and disruption of normal retinoid homeostasis. Special attention is paid to xenobiotic molecular targets (nuclear receptors, regulatory proteins, enzymes, and transporters) which affect retinoid metabolism and signaling. PMID:26311625

A case of all-trans retinoic acid-induced myositis in the treatment of acute promyelocytic leukaemia.

PubMed

Chan, K H; Yuen, S L S; Joshua, D

2005-12-01

The use of all-trans retinoic acid (ATRA) is now standard therapy for the treatment of acute promyelocytic leukaemia (APML). There have been increasing reports of ATRA-induced myositis, with its frequent association with retinoic acid syndrome and Sweet's syndrome. We report a case of a young man with APML who developed ATRA-induced myositis characterized by unexplained fevers, bilateral leg swelling and a non-painful purpuric, petechial rash, with prompt resolution of symptoms and signs with high-dose steroids and cessation of ATRA. Rapid recognition of this adverse reaction and prompt institution of steroids is of prime importance given its potentially fatal course.

The region of CQQQKPQRRP of PGC-1{alpha} interacts with the DNA-binding complex of FXR/RXR{alpha}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kanaya, Eiko; Jingami, Hisato

2006-04-14

PGC-1{alpha} co-activates transcription by several nuclear receptors. To study the interaction among PGC-1{alpha}, RXR{alpha}/FXR, and DNA, we performed electrophoresis mobility shift assays. The RXR{alpha}/FXR proteins specifically bound to DNA containing the IR-1 sequence in the absence of ligand. When the fusion protein of GST-PGC-1{alpha} was added to the mixture of RXR{alpha}/FXR/DNA, the ligand-influenced retardation of the mobility was observed. The ligand for RXR{alpha} (9-cis-retinoic acid) was necessary for this retardation, whereas, the ligand for FXR, chenodeoxycholic acid, barely had an effect. The results obtained using truncated PGC-1{alpha} proteins suggested that two regions are necessary for PGC-1{alpha} to interact with themore » DNA-binding complex of RXR{alpha}/FXR. One is the region of the second leucine-rich motif, and the other is that of the amino acid sequence CQQQKPQRRP, present between the second and third leucine-rich motifs. The results obtained with the SPQSS mutation for KPQRR suggested that the basic amino acids are important for the interaction.« less

Novel isotretinoin microemulsion-based gel for targeted topical therapy of acne: formulation consideration, skin retention and skin irritation studies

NASA Astrophysics Data System (ADS)

Patel, Mrunali R.; Patel, Rashmin B.; Parikh, Jolly R.; Patel, Bharat G.

2016-04-01

Isotretinoin was formulated in novel microemulsion-based gel formulation with the aim of improving its solubility, skin tolerability, therapeutic efficacy, skin-targeting efficiency and patient compliance. Microemulsion was formulated by the spontaneous microemulsification method using 8 % isopropyl myristate, 24 % Labrasol, 8 % plurol oleique and 60 % water as an external phase. All plain and isotretinoin-loaded microemulsions were clear and showed physicochemical parameters for the desired topical delivery and stability. The permeation profiles of isotretinoin through rat skin from selected microemulsion formulation followed zero-order kinetics. Microemulsion-based gel was prepared by incorporating Carbopol®971 in optimized microemulsion formulation having suitable skin permeation rate and skin uptake. Microemulsion-based gel showed desired physicochemical parameters and demonstrated advantage over marketed formulation in improving the skin tolerability of isotretinoin, indicating its potential in improving topical delivery of isotretinoin. The developed microemulsion-based gel may be a potential drug delivery vehicle for targeted topical delivery of isotretinoin in the treatment of acne.

Receptor-selective retinoids implicate retinoic acid receptor alpha and gamma in the regulation of bmp-2 and bmp-4 in F9 embryonal carcinoma cells.

PubMed

Rogers, M B

1996-01-01

The effect of retinoids on malignant cells and embryos indicates that retinoids influence the expression of growth factors or alter the response of cells to growth factors. The bone morphogenetic proteins, Bmp-2 and Bmp-4, are candidates for such growth factors because retinoic acid (RA) treatment of F9 embryonal carcinoma cells induced Bmp-2 mRNA, while simultaneously repressing Bmp-4 levels. Also, recombinant Bmp-2 affected the growth and differentiation of these cells. Regulation of each gene was concentration dependent and required continuous RA treatment. The short half-lives of the Bmp-2 (75 +/- 11 min) and Bmp-4 (70 +/- 4 min) mRNAs suggest that their abundance is primarily controlled at the transcriptional level. To determine which RA receptor (RAR) controls bmp-2 and bmp-4 expression, F9 cells were exposed to various receptor-selective retinoids. RAR alpha- and gamma-selective retinoids induced Bmp-2 and repressed Bmp-4 equally as well as all-trans RA. In contrast, a RAR beta-selective retinoid had little effect on Bmp-2 induction but repressed Bmp-4. A RAR alpha-selective antagonist inhibited all-trans RA stimulation of Bmp-2, although not as dramatically as a RAR beta gamma-selective antagonist. No differences were observed between Bmp levels in all-trans RA and 9-cis RA-treated cells, indicating that the RXRs play little part in controlling these genes. The results are consistent with RAR alpha and gamma-controlled Bmp-2 and Bmp-4 regulation.

Adaptive responses induced by 24S-hydroxycholesterol through liver X receptor pathway reduce 7-ketocholesterol-caused neuronal cell death☆

PubMed Central

Okabe, Akishi; Urano, Yasuomi; Itoh, Sayoko; Suda, Naoto; Kotani, Rina; Nishimura, Yuki; Saito, Yoshiro; Noguchi, Noriko

2013-01-01

Lipid peroxidation products have been known to induce cellular adaptive responses and enhance tolerance against subsequent oxidative stress through up-regulation of antioxidant compounds and enzymes. 24S-hydroxycholesterol (24SOHC) which is endogenously produced oxysterol in the brain plays an important role in maintaining brain cholesterol homeostasis. In this study, we evaluated adaptive responses induced by brain-specific oxysterol 24SOHC in human neuroblastoma SH-SY5Y cells. Cells treated with 24SOHC at sub-lethal concentrations showed significant reduction in cell death induced by subsequent treatment with 7-ketocholesterol (7KC) in both undifferentiated and retinoic acid-differentiated SH-SY5Y cells. These adaptive responses were also induced by other oxysterols such as 25-hydroxycholesterol and 27-hydroxycholesterol which are known to be ligands of liver X receptor (LXR). Co-treatment of 24SOHC with 9-cis retinoic acid, a retinoid X receptor ligand, enhanced the adaptive responses. Knockdown of LXRβ by siRNA diminished the adaptive responses induced by 24SOHC almost completely. The treatment with 24SOHC induced the expression of LXR target genes, such as ATP-binding cassette transporter A1 (ABCA1) and G1 (ABCG1). The 24SOHC-induced adaptive responses were significantly attenuated by siRNA for ABCG1 but not by siRNA for ABCA1. Taken together, these results strongly suggest that 24SOHC at sub-lethal concentrations induces adaptive responses via transcriptional activation of LXR signaling pathway, thereby protecting neuronal cells from subsequent 7KC-induced cytotoxicity. PMID:24371802

ALTERATIONS IN A11 TRANS RETINOIC ACID METABOLISM IN LIVER MICROSOMES FROM MICE TREATED WITH HEPATOTUMORIGENIC AND NON-HEPATOTUMORIGENIC CONAZOLES

EPA Science Inventory

Conazoles are fungicides used in crop protection and as pharmaceuticals. Triadimefon and propiconazole are hepatotumorigenic in mice, while myclobutanil is not. Previous toxicogenomic studies suggest that alteration of the retinoic acid metabolism pathway may be a key event in co...

RETINOIC ACID INDUCTION OF CLEFT PALATE IN EGF AND TGF-ALPHA KNOCKOUT MICE: STAGE SPECIFIC INFLUENCES OF GROWTH FACTOR EXPRESSION

EPA Science Inventory

ABBOTT, B. D., LEFFLER, K.E. AND BUCKALEW, A.R, Reproductive Toxicology Division, NHEERL, ORD, US EPA, Research Triangle Park, North Carolina. Retinoic acid induction of cleft palate (CP) in EGF and TGF knockout mice: Stage specific influences of growth factor expression.
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ALDH1A3 Mutations Cause Recessive Anophthalmia and Microphthalmia

PubMed Central

Fares-Taie, Lucas; Gerber, Sylvie; Chassaing, Nicolas; Clayton-Smith, Jill; Hanein, Sylvain; Silva, Eduardo; Serey, Margaux; Serre, Valérie; Gérard, Xavier; Baumann, Clarisse; Plessis, Ghislaine; Demeer, Bénédicte; Brétillon, Lionel; Bole, Christine; Nitschke, Patrick; Munnich, Arnold; Lyonnet, Stanislas; Calvas, Patrick; Kaplan, Josseline; Ragge, Nicola; Rozet, Jean-Michel

2013-01-01

Anophthalmia and microphthalmia (A/M) are early-eye-development anomalies resulting in absent or small ocular globes, respectively. A/M anomalies occur in syndromic or nonsyndromic forms. They are genetically heterogeneous, some mutations in some genes being responsible for both anophthalmia and microphthalmia. Using a combination of homozygosity mapping, exome sequencing, and Sanger sequencing, we identified homozygosity for one splice-site and two missense mutations in the gene encoding the A3 isoform of the aldehyde dehydrogenase 1 (ALDH1A3) in three consanguineous families segregating A/M with occasional orbital cystic, neurological, and cardiac anomalies. ALDH1A3 is a key enzyme in the formation of a retinoic acid gradient along the dorso-ventral axis during early eye development. Transitory expression of mutant ALDH1A3 open reading frames showed that both missense mutations reduce the accumulation of the enzyme, potentially leading to altered retinoic acid synthesis. Although the role of retinoic acid signaling in eye development is well established, our findings provide genetic evidence of a direct link between retinoic-acid-synthesis dysfunction and early-eye-development anomalies in humans. PMID:23312594

Phase II Trial of β-All-trans-Retinoic Acid for Cervical Intraepithelial Neoplasia Delivered via a Collagen Sponge and Cervical Cap

PubMed Central

Graham, Vivian; Surwit, Earl S.; Weiner, Sheldon; Meyskens, Frank L.

1986-01-01

Retinoids are effective suppressors of the phenotypic development of cancer in many animal systems, whether the process is initiated by chemical, physical or viral carcinogens. Cases of cervical intraepithelial neoplasia are excellent for studying the effectiveness of retinoids as chemopreventive agents because the process can be closely followed by serial colposcopic and pathologic (cytology or biopsy) means and changes in the condition safely monitored. We have previously conducted a phase I study of trans-retinoic acid (Tretinoin) given topically by a collagen sponge and cervical cap. A dose of 0.372% was selected for phase II trial. We have treated 20 patients with topical retinoic acid, and a complete response with total regression of disease was obtained in 50%. Systemic and cervical side effects were mild and vaginal side effects moderate but tolerable. These results provide a clinical basis for a randomized, double-blind phase III study to definitely answer the question of whether retinoic acid is an effective chemopreventive agent for cervical cancer. ImagesFigure. 1. PMID:3765597

Tripartite Motif 24 (Trim24/Tif1α) Tumor Suppressor Protein Is a Novel Negative Regulator of Interferon (IFN)/Signal Transducers and Activators of Transcription (STAT) Signaling Pathway Acting through Retinoic Acid Receptor α (Rarα) Inhibition*

PubMed Central

Tisserand, Johan; Khetchoumian, Konstantin; Thibault, Christelle; Dembélé, Doulaye; Chambon, Pierre; Losson, Régine

2011-01-01

Recent genetic studies in mice have established that the nuclear receptor coregulator Trim24/Tif1α suppresses hepatocarcinogenesis by inhibiting retinoic acid receptor α (Rara)-dependent transcription and cell proliferation. However, Rara targets regulated by Trim24 remain unknown. We report that the loss of Trim24 resulted in interferon (IFN)/STAT pathway overactivation soon after birth (week 5). Despite a transient attenuation of this pathway by the induction of several IFN/STAT pathway repressors later in the disease, this phenomenon became more pronounced in tumors. Remarkably, Rara haplodeficiency, which suppresses tumorigenesis in Trim24−/− mice, prevented IFN/STAT overactivation. Moreover, together with Rara, Trim24 bound to the retinoic acid-responsive element of the Stat1 promoter and repressed its retinoic acid-induced transcription. Altogether, these results identify Trim24 as a novel negative regulator of the IFN/STAT pathway and suggest that this repression through Rara inhibition may prevent liver cancer. PMID:21768647

Reactions of vitamin A with acceptors of electrons. Interactions with iodine and the formation of iodide

PubMed Central

Lucy, J. A.; Lichti, F. Ulrike

1969-01-01

1. The reactions of retinol and retinoic acid with iodine were investigated since knowledge of the chemical reactions of vitamin A with acceptors of electrons may shed light on its biochemical mode of action. 2. Colloidal retinol, but not retinoic acid, reacts with iodine to yield a blue–green complex that rapidly decomposes, giving iodide and an unknown species with λmax. at 870mμ. 3. In addition, both retinol and retinoic acid reduce iodine to iodide by a reaction that does not involve an intermediate coloured complex; this reaction appears to yield unstable carbonium ion derivatives of the vitamin. 4. The presence of water greatly facilitates the production of iodide from vitamin A and iodine. 5. Possible chemical pathways involved in these reactions are discussed. 6. It is suggested that the chemical properties of retinol and retinoic acid that underlie their biochemical behaviour might be apparent only when the molecules are at a lipid–water interface, and that vitamin A might be expected to react with a number of different electron acceptors in vivo. PMID:5801297

Conjugated Fatty Acid Synthesis

PubMed Central

Rawat, Richa; Yu, Xiao-Hong; Sweet, Marie; Shanklin, John

2012-01-01

Conjugated linolenic acids (CLNs), 18:3 Δ9,11,13, lack the methylene groups found between the double bonds of linolenic acid (18:3 Δ9,12,15). CLNs are produced by conjugase enzymes that are homologs of the oleate desaturases FAD2. The goal of this study was to map the domain(s) within the Momordica charantia conjugase (FADX) responsible for CLN formation. To achieve this, a series of Momordica FADX-Arabidopsis FAD2 chimeras were expressed in the Arabidopsis fad3fae1 mutant, and the transformed seeds were analyzed for the accumulation of CLN. These experiments identified helix 2 and the first histidine box as a determinant of conjugase product partitioning into punicic acid (18:3 Δ9cis,11trans,13cis) or α-eleostearic acid (18:3 Δ9cis,11trans,13trans). This was confirmed by analysis of a FADX mutant containing six substitutions in which the sequence of helix 2 and first histidine box was converted to that of FAD2. Each of the six FAD2 substitutions was individually converted back to the FADX equivalent identifying residues 111 and 115, adjacent to the first histidine box, as key determinants of conjugase product partitioning. Additionally, expression of FADX G111V and FADX G111V/D115E resulted in an approximate doubling of eleostearic acid accumulation to 20.4% and 21.2%, respectively, compared with 9.9% upon expression of the native Momordica FADX. Like the Momordica conjugase, FADX G111V and FADX D115E produced predominantly α-eleostearic acid and little punicic acid, but the FADX G111V/D115E double mutant produced approximately equal amounts of α-eleostearic acid and its isomer, punicic acid, implicating an interactive effect of residues 111 and 115 in punicic acid formation. PMID:22451660

ISX is a retinoic acid-sensitive gatekeeper that controls intestinal β,β-carotene absorption and vitamin A production

PubMed Central

Lobo, Glenn P.; Hessel, Susanne; Eichinger, Anne; Noy, Noa; Moise, Alexander R.; Wyss, Adrian; Palczewski, Krzysztof; von Lintig, Johannes

2010-01-01

The uptake of dietary lipids from the small intestine is a complex process that depends on the activities of specific membrane receptors with yet unknown regulatory mechanisms. Using both mouse models and human cell lines, we show here that intestinal lipid absorption by the scavenger receptor class B type 1 (SR-BI) is subject to control by retinoid signaling. Retinoic acid via retinoic acid receptors induced expression of the intestinal transcription factor ISX. ISX then repressed the expression of SR-B1 and the carotenoid-15,15′-oxygenase Bcmo1. BCMO1 acts downstream of SR-BI and converts absorbed β,β-carotene to the retinoic acid precursor, retinaldehyde. Using BCMO1-knockout mice, we demonstrated increased intestinal SR-BI expression and systemic β,β-carotene accumulation. SR-BI-dependent accumulation of β,β-carotene was prevented by dietary retinoids that induced ISX expression. Thus, our study revealed a diet-responsive regulatory network that controls β,β-carotene absorption and vitamin A production by negative feedback regulation. The role of SR-BI in the intestinal absorption of other dietary lipids, including cholesterol, fatty acids, and tocopherols, implicates retinoid signaling in the regulation of lipid absorption more generally and has clinical implications for diseases associated with dyslipidemia.—Lobo, G. P., Hessel, S., Eichinger, A., Noy, N., Moise, A. R., Wyss, A., Palczewski, K., von Lintig, J. ISX is a retinoic acid-sensitive gatekeeper that controls intestinal β,β-carotene absorption and vitamin A production. PMID:20061533

Functions of Intracellular Retinoid Binding-Proteins.

PubMed

Napoli, Joseph L

Multiple binding and transport proteins facilitate many aspects of retinoid biology through effects on retinoid transport, cellular uptake, metabolism, and nuclear delivery. These include the serum retinol binding protein sRBP (aka Rbp4), the plasma membrane sRBP receptor Stra6, and the intracellular retinoid binding-proteins such as cellular retinol-binding proteins (CRBP) and cellular retinoic acid binding-proteins (CRABP). sRBP transports the highly lipophilic retinol through an aqueous medium. The major intracellular retinol-binding protein, CRBP1, likely enhances efficient retinoid use by providing a sink to facilitate retinol uptake from sRBP through the plasma membrane or via Stra6, delivering retinol or retinal to select enzymes that generate retinyl esters or retinoic acid, and protecting retinol/retinal from excess catabolism or opportunistic metabolism. Intracellular retinoic acid binding-proteins (CRABP1 and 2, and FABP5) seem to have more diverse functions distinctive to each, such as directing retinoic acid to catabolism, delivering retinoic acid to specific nuclear receptors, and generating non-canonical actions. Gene ablation of intracellular retinoid binding-proteins does not cause embryonic lethality or gross morphological defects. Metabolic and functional defects manifested in knockouts of CRBP1, CRBP2 and CRBP3, however, illustrate their essentiality to health, and in the case of CRBP2, to survival during limited dietary vitamin A. Future studies should continue to address the specific molecular interactions that occur between retinoid binding-proteins and their targets and their precise physiologic contributions to retinoid homeostasis and function.

Retinoic acid is required for specification of the ventral eye field and for Rathke's pouch in the avian embryo.

PubMed

Maden, Malcolm; Blentic, Aida; Reijntjes, Susan; Seguin, Sophie; Gale, Emily; Graham, Anthony

2007-01-01

We have investigated the role of retinoic acid (RA) in eye development using the vitamin A deficient quail model system, which overcomes problems of retinoic acid synthesising enzyme redundancy in the embryo. In the absence of retinoic acid, the ventral optic stalk and ventral retina are missing, whereas the dorsal optic stalk and dorsal retina develop appropriately. Other ocular abnormalities observed were a thinner retina and the lack of differentiation of the lens. In an attempt to explain this, we studied the expression of various dorsally and ventrally expressed genes such as Pax2, Pax6, Tbx6, Vax2, Raldh1 and Raldh3 and noted that they were unchanged in their expression patterns. In contrast, the RA catabolising enzymes Cyp26A1 and Cyp26B1 which are known to be RA-responsive were not expressed at all in the developing eye. At much earlier stages, the expression domain of Shh in the prechordal plate was reduced, as was Nkx2.1 and we suggest a model whereby the eye field is specified according to the concentration of SHH protein that is present. We also describe another organ, Rathke's pouch which fails to develop in the absence of retinoic acid. We attribute this to the down-regulation of Bmp2, Shh and Fgf8 which are known to be involved in the induction of this structure.

Investigation of the photochemical changes of chlorogenic acids induced by ultraviolet light in model systems and in agricultural practice with Stevia rebaudiana cultivation as an example.

PubMed

Karaköse, Hande; Jaiswal, Rakesh; Deshpande, Sagar; Kuhnert, Nikolai

2015-04-08

Mono- and diacyl chlorogenic acids undergo photochemical trans-cis isomerization under ultraviolet (UV) irradiation. The photochemical equilibrium composition was established for eight selected derivatives. In contrast to all other dicaffeoylquinic acid derivatives, cynarin (1,3-dicaffeoylquinic acid) undergoes a [2 + 2] photochemical cycloaddition reaction, constituting a first example of Schmidt's law in a natural product family. The relevance of photochemical isomerization in agricultural practice was investigated using 120 samples of Stevia rebaudiana leave samples grown under defined cultivation conditions. Ratios of cis to trans chlorogenic acids were determined in leaf samples and correlated with climatic and harvesting conditions. The data indicate a clear correlation between the formation of cis-caffeoyl derivatives and sunshine hours prior to harvesting and illustrate the relevance of UV exposure to plant material affecting its phytochemical composition.

Reduced adiponectin expression after high-fat diet is associated with selective up-regulation of ALDH1A1 and further retinoic acid receptor signaling in adipose tissue

PubMed Central

Landrier, Jean-Francois; Kasiri, Elnaz; Karkeni, Esma; Mihály, Johanna; Béke, Gabriella; Weiss, Kathrin; Lucas, Renata; Aydemir, Gamze; Salles, Jérome; Walrand, Stéphane; de Lera, Angel R.; Rühl, Ralph

2017-01-01

Adiponectin is an adipocyte-derived adipokine with potent antidiabetic, anti-inflammatory, and antiatherogenic activity. Long-term, high-fat diet results in gain of body weight, adiposity, further inflammatory-based cardiovascular diseases, and reduced adiponectin secretion. Vitamin A derivatives/retinoids are involved in several of these processes, which mainly take place in white adipose tissue (WAT). In this study, we examined adiponectin expression as a function of dietary high-fat and high–vitamin A conditions in mice. A decrease of adiponectin expression in addition to an up-regulation of aldehyde dehydrogenase A1 (ALDH1A1), retinoid signaling, and retinoic acid response element signaling was selectively observed in WAT of mice fed a normal–vitamin A, high-fat diet. Reduced adiponectin expression in WAT was also observed in mice fed a high–vitamin A diet. Adipocyte cell culture revealed that endogenous and synthetic retinoic acid receptor (RAR)α- and RARγ-selective agonists, as well as a synthetic retinoid X receptor agonist, efficiently reduced adiponectin expression, whereas ALDH1A1 expression only increased with RAR agonists. We conclude that reduced adiponectin expression under high-fat dietary conditions is dependent on 1) increased ALDH1A1 expression in adipocytes, which does not increase all-trans-retinoic acid levels; 2) further RAR ligand–induced, WAT-selective, increased retinoic acid response element–mediated signaling; and 3) RAR ligand–dependent reduction of adiponectin expression.—Landrier, J.-F., Kasiri, E., Karkeni, E., Mihály, J., Béke, G., Weiss, K., Lucas, R., Aydemir, G., Salles, J., Walrand, S., de Lera, A. R., Rühl, R. Reduced adiponectin expression after high-fat diet is associated with selective up-regulation of ALDH1A1 and further retinoic acid receptor signaling in adipose tissue. PMID:27729412

Degradation of 1,3-Dichloropropene by Pseudomonas cichorii 170

PubMed Central

Poelarends, Gerrit J.; Wilkens, Marga; Larkin, Michael J.; van Elsas, Jan Dirk; Janssen, Dick B.

1998-01-01

The gram-negative bacterium Pseudomonas cichorii 170, isolated from soil that was repeatedly treated with the nematocide 1,3-dichloropropene, could utilize low concentrations of 1,3-dichloropropene as a sole carbon and energy source. Strain 170 was also able to grow on 3-chloroallyl alcohol, 3-chloroacrylic acid, and several 1-halo-n-alkanes. This organism produced at least three different dehalogenases: a hydrolytic haloalkane dehalogenase specific for haloalkanes and two 3-chloroacrylic acid dehalogenases, one specific for cis-3-chloroacrylic acid and the other specific for trans-3-chloroacrylic acid. The haloalkane dehalogenase and the trans-3-chloroacrylic acid dehalogenase were expressed constitutively, whereas the cis-3-chloroacrylic acid dehalogenase was inducible. The presence of these enzymes indicates that 1,3-dichloropropene is hydrolyzed to 3-chloroallyl alcohol, which is oxidized in two steps to 3-chloroacrylic acid. The latter compound is then dehalogenated, probably forming malonic acid semialdehyde. The haloalkane dehalogenase gene, which is involved in the conversion of 1,3-dichloropropene to 3-chloroallyl alcohol, was cloned and sequenced, and this gene turned out to be identical to the previously studied dhaA gene of the gram-positive bacterium Rhodococcus rhodochrous NCIMB13064. Mutants resistant to the suicide substrate 1,2-dibromoethane lacked haloalkane dehalogenase activity and therefore could not utilize haloalkanes for growth. PCR analysis showed that these mutants had lost at least part of the dhaA gene. PMID:9687453

A practical approach for the use of oral isotretinoin for infantile acne.

PubMed

Barnes, Cheryl J; Eichenfield, Lawrence F; Lee, Jungho; Cunningham, Bari B

2005-01-01

Infantile acne is a rare occurrence. It is more common in boys and predominately occurs on the cheeks in infants between the ages of 1 and 16 months. Clinically, the lesions range from comedones to inflammatory papulopustules to cysts. Successful therapies include topical tretinoin, benzoyl peroxide and topical and oral erythromycin. For more serious cases, oral isotretinoin (Accutane) has been reported to successfully treat recalcitrant infantile cystic acne. We describe two additional patients with infantile cystic acne treated successfully with oral isotretinoin. The dose of isotretinoin used ranged from 0.2 mg/kg/day to 1.5 mg/kg/day. The treatment duration varied from 5 to 14 months. Careful monthly monitoring is recommended because of the many side effects reported with isotretinoin. Practical tips for the administration of oral isotretinoin in infants are reviewed.

Transient phenomena in the pulse radiolysis of retinyl polyenes. 5. Association of radical cations with parent molecules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bobrowski, K.; Das, P.K.

1986-02-27

At relatively high concentrations (1-10 mM) in O/sub 2/-saturated acetone, pulse radiolysis of all-trans-retinal, -retinoic acid, and -methyl retinoate gives rise to fast transient absorption processes that are best explained in terms of association of radical cations with parent polyenes to form dimers. From the concentration dependence of initial decay/formation kinetics, equilibrium constants (K) for monomer/dimer interconversion are measured to be 220-440 M/sup -1/ (in acetone). On going from acetone to 1,2-dichloroethane, K values for retinal and retinoic acid increase almost by an order of magnitude. For all trans-retinol and retinyl acetate, radical cation dimer formation appears to be negligiblemore » in the concentration range 1-10 mM of the polyene substrates (based on the lack of transient absorption changes seen with retinal and retinoic acid/ester). 24 references, 6 figures, 1 table.« less

Synthesis of highly functionalized macrocycles by the peripheral functionalization of macrocyclic diimines.

PubMed

Sierra, Miguel A; Pellico, Daniel; Gómez-Gallego, Mar; Mancheño, María José; Torres, Rosario

2006-11-10

The easily available macrocyclic diimines 4-7 can be stereoselectively transformed to macrocyclic bis-beta-amino acids 13-17, macrocyclic bisazetidines 18-20, and macrocyclic bisamides 21 and 22 by means of the corresponding bis-beta-lactam scaffolds 8-12. These key intermediates are available through standard Staudinger reaction and obtained as the cis-cis diastereomers, exclusively. An interesting relation between the proximity of the reactive C=N bonds and the selectivity in the formation of the bis-beta-lactams 8-12 is observed. Thus, diimine 4 leads to low selectivities, producing a 1:1 mixture of cis-syn-cis and cis-anti-cis diastereomers, while diimines 5-7 having the diimine sites more separated lead almost exclusively to the cis-anti-cis diastereomers. The stereochemistry of all the products was unambiguously assigned by X-ray diffraction analysis of compounds cis-syn-cis 8 and cis-anti-cis 12-Co2CO6 complex.

Isolation of pyrrolocins A-C: cis- and trans-decalin tetramic acid antibiotics from an endophytic fungal-derived pathway.

PubMed

Jadulco, Raquel C; Koch, Michael; Kakule, Thomas B; Schmidt, Eric W; Orendt, Anita; He, Haiyin; Janso, Jeffrey E; Carter, Guy T; Larson, Erica C; Pond, Christopher; Matainaho, Teatulohi K; Barrows, Louis R

2014-11-26

Three new decalin-type tetramic acid analogues, pyrrolocins A (1), B (2), and C (3), were defined as products of a metabolic pathway from a fern endophyte, NRRL 50135, from Papua New Guinea. NRRL 50135 initially produced 1 but ceased its production before chemical or biological evaluation could be completed. Upon transfer of the biosynthetic pathway to a model host, 1-3 were produced. All three compounds are structurally related to equisetin-type compounds, with 1 and 3 having a trans-decalin ring system, while 2 has a cis-fused decalin. All were active against Mycobacterium tuberculosis, with the trans-decalin analogues 1 and 3 exhibiting lower MICs than the cis-decalin analogue 2. Here we report the isolation, structure elucidation, and antimycobacterial activities of 1-3 from the recombinant expression as well as the isolation of 1 from the wild-type fungus NRRL 50135.

Presumed Isotretinoin-Induced, Concomitant Autoimmune Thyroid Disease and Ocular Myasthenia Gravis: A Case Report

PubMed Central

Gursoy, Huseyin; Cakmak, Idil; Yildirim, Nilgun; Basmak, Hikmet

2012-01-01

Introduction There are many adverse effects that have been described for isotretinoin. To the best of our knowledge, this is the first report of a possible association of oral isotretinoin intake with autoimmune thyroiditis and ocular myasthenia gravis (OMG). Case Presentation A 19-year-old Caucasian male, who had used oral isotretinoin for severe acne disease for the previous six months, was referred to our clinic. He had a three-week history of diplopia and variable bilateral ptosis. Physical examination showed moderate periorbital edema and limitations of up- and down-gaze in the left eye. Laboratory findings and thyroid ultrasound were consistent with autoimmune thyroiditis. Antithyroid therapy did not relieve the clinical symptoms. Concomitant OMG was suspected. Variable ptosis and a positive response to oral prednisolone of 40 mg/day and pyridostigmine of 360 mg/day supported the diagnosis of concomitant autoimmune thyroiditis and OMG. Conclusion Autoimmune disorders may be triggered by oral isotretinoin treatment. Clinicians prescribing isotretinoin should be aware of the possible association between isotretinoin intake and concomitant autoimmune thyroiditis and OMG. PMID:23275770

TERATOGENIC EFFECTS OF RETINOIC ACID ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR AND TRANSFORMING GROWTH FACTOR-ALPHA

EPA Science Inventory

Background: EGF and TGF regulate cell proliferation and differentiation in the embryo. The induction of cleft palate (CP) by all trans retinoic acid (RA) was associated with altered expression of TGF, EGF receptor and binding of EGF. The present study uses knockout (KO) mice to e...

LIMB DEFECTS INDUCED BY RETINOIC ACID SIGNALING ANTAGONISM AND SYNTHESIS INHIBITION ARE CONSISTENT WITH ETHANOL-INDUCED LIMB DEFECTS

EPA Science Inventory

Limb defects induced by retinoic acid signaling antagonism and synthesis inhibition are consistent with ethanol-induced limb defects

Johnson CS1, Sulik KK1,2, Hunter, ES III3
1Department of Cell and Developmental Biology, University of North Carolina at Chapel Hill, NC....

Retinoic acid: an educational "vitamin elixir" for gut-seeking T cells.

PubMed

Mora, J Rodrigo; von Andrian, Ulrich H

2004-10-01

T cell priming by dendritic cells (DC) from gut-associated lymphoid tissues gives rise to effector cells with pronounced gut tropism. The mechanism for DC-dependent imprinting of gut specificity has remained unknown. New findings point to retinoic acid, which is uniquely produced by intestinal DC, but not by DC from other lymphoid organs.

Integrating Retinoic Acid Signaling with Brain Function

ERIC Educational Resources Information Center

Luo, Tuanlian; Wagner, Elisabeth; Drager, Ursula C.

2009-01-01

The vitamin A derivative retinoic acid (RA) regulates the transcription of about a 6th of the human genome. Compelling evidence indicates a role of RA in cognitive activities, but its integration with the molecular mechanisms of higher brain functions is not known. Here we describe the properties of RA signaling in the mouse, which point to…

Retinoid Pathway and Cancer Therapeutics

PubMed Central

Bushue, Nathan; Wan, Yu-Jui Yvonne

2010-01-01

The retinoids are a class of compounds that are structurally related to vitamin A. Retinoic acid, which is the active metabolite of retinol, regulates a wide range of biological processes including development, differentiation, proliferation, and apoptosis. Retinoids exert their effects through a variety of binding proteins including cellular retinol binding protein (CRBP), retinol-binding proteins (RBP), cellular retinoic acid-binding protein (CRABP), and nuclear receptors i.e. retinoic acid receptor (RAR) and retinoid × receptor (RXR). Because of the pleiotropic effects of retinoids, understanding the function of these binding proteins and nuclear receptors assists us in developing compounds that have specific effects. This review summarizes our current understanding of how retinoids are processed and act with the emphasis on the application of retinoids in cancer treatment and prevention. PMID:20654663

Food increases the bioavailability of isotretinoin.

PubMed

Colburn, W A; Gibson, D M; Wiens, R E; Hanigan, J J

1983-01-01

Twenty healthy male subjects received 80 mg (2 X 40 mg SEG capsules) oral isotretinoin separated by two-week washout periods in an open randomized crossover design. Isotretinoin was administered during a complete fast, 1 hour after a standard breakfast, with a standard breakfast, or 1 hour before a standard breakfast. Blood samples were obtained at specific times over a 72-hour period. Isotretinoin blood concentrations were determined by a specific HPLC method. The relative bioavailability (AUC) of isotretinoin was found to be approximately 1.5 to 2 times greater when the dose was administered 1 hour before, concomitantly with, or 1 hour after a meal than when it was given during a complete fast. In addition, because the Cmax value is lower when the dose is administered with food rather than 1 hour after a meal, coadministration of isotretinoin with food may be the best method of administration.

Effects of retinoids and thiazolidinediones on proliferation, insulin release, insulin mRNA, GLUT 2 transporter protein and mRNA of INS-1 cells.

PubMed

Blumentrath, J; Neye, H; Verspohl, E J

2001-09-01

Both 9-cis-retinoic acid (9cRA) and all-trans-retinoic acid (ATRA) are active metabolites of vitamin A (retinol). There exists an interaction between retinoid receptors and peroxisome proliferator-activated receptors (PPARgamma). To define their functions in an insulin secreting system the effects of ATRA, 9cRA and the PPARgamma agonist rosiglitazone on cell proliferation, insulin release and glucose transporter (GLUT) 2 of INS-1 cells were tested. Retinoic acid receptor (RAR-alpha and -gamma) and retinoid X receptor (RXR-alpha and -beta) proteins are present (immunoblots). Both 9cRA and ATRA inhibit INS-1 cell proliferation ([3H]-thymidine assay) in a concentration dependent manner. Both 9cRA and ATRA increased insulin release, but only ATRA ralsed the GLUT 2 mRNA in a bell-shaped concentration response curve after 48 h. The insulinotropic effect of one compound is not significantly superimposed by the other indicating that the same binding sites are used by 9cRA and ATRA. The acute and chronic effects of the PPARgamma agonist rosiglitazone on insulin release were additionally determined since glitazones act as transcription factors together with RXR agonists. At high concentrations (100 microM) rosiglitazone inhibited glucose (8.3 mM) stimulated insulin secretion (acute experiment over 60 min). Insulin secretion, however, was increased during a 24 h treatment at a concentration of 10 microM and again inhibited at 100 microM. Changes in preproinsulin mRNA expression were not observed. Rosiglitazone (100 microM) increased GLUT 2 mRNA paralleled by an increase of GLUT 2 protein, but only after 24 h of treatment. This data indicate that RAR and RXR mediate insulin release. The changes in GLUT 2 have no direct impact on insulin release; the inhibition seen at high concentrations of either compound is possibly the result of the observed inhibition of cell proliferation. Effects of rosiglitazone on preproinsulin mRNA and GLUT 2 (mRNA and protein) do not play a role in modulating insulin secretion. With the presence of an RXR receptor agonist the effect of rosiglitazone on insulin release becomes stimulatory. Thus the effects of RAR-, RXR agonists and rosiglitazone depend on their concentrations, the duration of their presence and are due to specific interactions. Copyright 2001 John Wiley & Sons, Ltd.

Phytol metabolites are circulating dietary factors that activate the nuclear receptor RXR.

PubMed Central

Kitareewan, S; Burka, L T; Tomer, K B; Parker, C E; Deterding, L J; Stevens, R D; Forman, B M; Mais, D E; Heyman, R A; McMorris, T; Weinberger, C

1996-01-01

RXR is a nuclear receptor that plays a central role in cell signaling by pairing with a host of other receptors. Previously, 9-cis-retinoic acid (9cRA) was defined as a potent RXR activator. Here we describe a unique RXR effector identified from organic extracts of bovine serum by following RXR-dependent transcriptional activity. Structural analyses of material in active fractions pointed to the saturated diterpenoid phytanic acid, which induced RXR-dependent transcription at concentrations between 4 and 64 microM. Although 200 times more potent than phytanic acid, 9cRA was undetectable in equivalent amounts of extract and cannot be present at a concentration that could account for the activity. Phytanic acid, another phytol metabolite, was synthesized and stimulated RXR with a potency and efficacy similar to phytanic acid. These metabolites specifically displaced [3H]-9cRA from RXR with Ki values of 4 microM, indicating that their transcriptional effects are mediated by direct receptor interactions. Phytol metabolites are compelling candidates for physiological effectors, because their RXR binding affinities and activation potencies match their micromolar circulating concentrations. Given their exclusive dietary origin, these chlorophyll metabolites may represent essential nutrients that coordinate cellular metabolism through RXR-dependent signaling pathways. PMID:8856661

Can we ensure the safe use of known human teratogens? Introduction of generic isotretinoin in the US as an example.

PubMed

Honein, Margaret A; Moore, Cynthia A; Erickson, J David

2004-01-01

The prescription of known teratogenic medications requires a careful balance between allowing women access to medications that they might need and avoiding unnecessary exposure to these medications during pregnancy because of their devastating fetal effects. Isotretinoin, a potent human teratogen, is of particular concern because of its widespread use among reproductive-aged women and the dramatic increase in use from 1992 through 2000. A revised risk management system was implemented in 2002 because of concerns about the continued occurrence of isotretinoin-exposed pregnancies. However, the recent approval of three generic versions of isotretinoin in the US has further complicated risk management and raises concerns that use might increase further if the lower cost of generics serves to increase accessibility. There are now four separate isotretinoin risk management systems in the US, each with its own distinct packaging, though the requirements for and substance of each are identical. Some additional concrete steps could be taken to minimise any unnecessary use of isotretinoin and help allow an adequate assessment of the current risk management systems. In addition to being familiar with and following all aspects of the current risk management system, physicians could choose to limit the use of isotretinoin to those who meet the labelled indications in order to reduce the number of exposed pregnancies. All four companies currently marketing isotretinoin in the US could jointly and voluntarily establish a consolidated, mandatory registration and follow-up of all women of reproductive potential who receive an isotretinoin prescription. Mandatory registration has many challenges, but it could allow a clear accounting of the total number of women for whom follow-up information is and is not available. Although the companies cannot be legally compelled to use a consolidated approach, the use of a single registry for the originator's product and all generic brands would allow identification of duplicates and also avoid the confusion that is introduced by providing materials that not only look different, but also have different addresses, contact information and names for participation in follow-up surveys. This is particularly important because women might take more than one version of isotretinoin during a single course of therapy or might receive a different programme's materials from their doctor than from the pharmacy. Though the introduction of generic versions of isotretinoin further complicates risk management, the companies marketing isotretinoin have an opportunity to work together to demonstrate their commitment to both limit the occurrence of exposed pregnancies and conduct a meaningful evaluation of the occurrence of pregnancies exposed to isotretinoin.

Impaired Development of Left Anterior Heart Field by Ectopic Retinoic Acid Causes Transposition of the Great Arteries

PubMed Central

Narematsu, Mayu; Kamimura, Tatsuya; Yamagishi, Toshiyuki; Fukui, Mitsuru; Nakajima, Yuji

2015-01-01

Background Transposition of the great arteries is one of the most commonly diagnosed conotruncal heart defects at birth, but its etiology is largely unknown. The anterior heart field (AHF) that resides in the anterior pharyngeal arches contributes to conotruncal development, during which heart progenitors that originated from the left and right AHF migrate to form distinct conotruncal regions. The aim of this study is to identify abnormal AHF development that causes the morphology of transposition of the great arteries. Methods and Results We placed a retinoic acid–soaked bead on the left or the right or on both sides of the AHF of stage 12 to 14 chick embryos and examined the conotruncal heart defect at stage 34. Transposition of the great arteries was diagnosed at high incidence in embryos for which a retinoic acid–soaked bead had been placed in the left AHF at stage 12. Fluorescent dye tracing showed that AHF exposed to retinoic acid failed to contribute to conotruncus development. FGF8 and Isl1 expression were downregulated in retinoic acid–exposed AHF, and differentiation and expansion of cardiomyocytes were suppressed in cultured AHF in medium supplemented with retinoic acid. Conclusions The left AHF at the early looped heart stage, corresponding to Carnegie stages 10 to 11 (28 to 29 days after fertilization) in human embryos, is the region of the impediment that causes the morphology of transposition of the great arteries. PMID:25929268

Enhanced high-performance liquid chromatography method for the determination of retinoic acid in plasma. Development, optimization and validation.

PubMed

Teglia, Carla M; Gil García, María D; Galera, María Martínez; Goicoechea, Héctor C

2014-08-01

When determining endogenous compounds in biological samples, the lack of blank or analyte-free matrix samples involves the use of alternative strategies for calibration and quantitation. This article deals with the development, optimization and validation of a high performance liquid chromatography method for the determination of retinoic acid in plasma, obtaining at the same time information about its isomers, taking into account the basal concentration of these endobiotica. An experimental design was used for the optimization of three variables: mobile phase composition, flow rate and column temperature through a central composite design. Four responses were selected for optimization purposes (area under the peaks, quantity of peaks, analysis time and resolution between the first principal peak and the following one). The optimum conditions resulted in a mobile phase consisting of methanol 83.4% (v/v), acetonitrile 0.6% (v/v) and acid aqueous solution 16.0% (v/v); flow rate of 0.68 mL min(-1) and an column temperature of 37.10 °C. Detection was performed at 350 nm by a diode array detector. The method was validated following a holistic approach that included not only the classical parameters related to method performance but also the robustness and the expected proportion of acceptable results lying inside predefined acceptability intervals, i.e., the uncertainty of measurements. The method validation results indicated a high selectivity and good precision characteristics that were studied at four concentration levels, with RSD less than 5.0% for retinoic acid (less than 7.5% for the LOQ concentration level), in intra and inter-assay precision studies. Linearity was proved for a range from 0.00489 to 15.109 ng mL(-1) of retinoic acid and the recovery, which was studied at four different fortification levels in phuman plasma samples, varied from 99.5% to 106.5% for retinoic acid. The applicability of the method was demonstrated by determining retinoic acid and obtaining information about its isomers in human and frog plasma samples from different origins. Copyright © 2014 Elsevier B.V. All rights reserved.

Updated Physician’s Guide to the Off-label Uses of Oral Isotretinoin

PubMed Central

Peterson, Nathan; Peterson, Michael

2014-01-01

While oral isotretinoin is renowned for its ability to treat acne vulgaris, many of its off-label uses continue to go underappreciated. Since the last review on the unapproved indications of isotretinoin, relevant publications have surfaced with new recommendations. This article attempts to provide physicians with the latest information regarding successful and unsuccessful use of isotretinoin as an effective treatment for dermatological conditions, such as rosacea, psoriasis, pityriasis rubra pilaris, condyloma acuminatum, granuloma annulare, Darier’s disease, systemic cutaneous lupus erythematosus, nonmelanoma skin cancer, and hidradenitis suppurativa. Variations in dosage regimens and isotretinoin viability as an alternative to other standard treatments are also discussed in relation to these conditions. PMID:24765227

Structure-Activity Correlations with Compounds Related to Abscisic Acid 1

PubMed Central

Sondheimer, Ernest; Walton, Daniel C.

1970-01-01

Inhibition of cell expansion of excised embryonic axes of Phaseolus vulgaris was used to evaluate the growth-inhibiting activity of abscisic acid and related compounds. None of the 13 compounds tested was as active as abscisic acid. 4-Hydroxyisophorone, a substance representative of the abscisic acid ring system was essentially inactive; cis, trans-3-methylsorbic acid, a compound resembling the side chain of abscisic acid, had low activity; and cis, trans-β-ionylideneacetic acid was one-sixth as active. Loss of the ring double bond results in a drastic decrease in biological activity. Comparison of our results with those reported previously leads to the suggestion that the double bond of the cyclohexyl moiety may have an important function in determining the degree of activity of cis, trans-ionylideneacetic acids. Two modes of action are discussed. It seems possible that the ring double bond is involved in covalent bonding in binding of the abscisic acid analogue to macromolecules. This may require formation of an intermediate epoxide. It can also be argued that stereochemical differences between cyclohexane derivatives are important factors in determining the degree of biological activity. PMID:5423465

Azadirachtin interacts with retinoic acid receptors and inhibits retinoic acid-mediated biological responses.

PubMed

Thoh, Maikho; Babajan, Banaganapalli; Raghavendra, Pongali B; Sureshkumar, Chitta; Manna, Sunil K

2011-02-11

Considering the role of retinoids in regulation of more than 500 genes involved in cell cycle and growth arrest, a detailed understanding of the mechanism and its regulation is useful for therapy. The extract of the medicinal plant Neem (Azadirachta indica) is used against several ailments especially for anti-inflammatory, anti-itching, spermicidal, anticancer, and insecticidal activities. In this report we prove the detailed mechanism on the regulation of retinoic acid-mediated cell signaling by azadirachtin, active components of neem extract. Azadirachtin repressed all trans-retinoic acid (ATRA)-mediated nuclear transcription factor κB (NF-κB) activation, not the DNA binding but the NF-κB-dependent gene expression. It did not inhibit IκBα degradation, IκBα kinase activity, or p65 phosphorylation and its nuclear translocation but inhibited NF-κB-dependent reporter gene expression. Azadirachtin inhibited TRAF6-mediated, but not TRAF2-mediated NF-κB activation. It inhibited ATRA-induced Sp1 and CREB (cAMP-response element-binding protein) DNA binding. Azadirachtin inhibited ATRA binding with retinoid receptors, which is supported by biochemical and in silico evidences. Azadirachtin showed strong interaction with retinoid receptors. It suppressed ATRA-mediated removal of retinoid receptors, bound with DNA by inhibiting ATRA binding to its receptors. Overall, our data suggest that azadirachtin interacts with retinoic acid receptors and suppresses ATRA binding, inhibits falling off the receptors, and activates transcription factors like CREB, Sp1, NF-κB, etc. Thus, azadirachtin exerts anti-inflammatory and anti-metastatic responses by a novel pathway that would be beneficial for further anti-inflammatory and anti-cancer therapies.

Epidermal effects of tretinoin and isotretinoin: influence of isomerism.

PubMed

Tadini, K A; Gaspar, L R; Maia Campos, P M B G

2006-05-01

The efficacy of tretinoin is well established in the treatment of acne and photoaged skin, however as a typical side effect of tretinoin treatment most patients develop a low-grade irritant dermatitis. Since isotretinoin topical treatment usually shows much lower incidence and intensity of adverse effects than tretinoin topical treatment, histological studies are needed to scientifically evaluate the effects of isotretinoin application on epidermis and also to assess if it can be used in anti-aging products as an alternative to tretinoin. Thus, the aim of this study was to compare the effects of topical use of tretinoin or isotretinoin on hairless mice epidermis, using appropriate histopathological and histometric techniques, in order to evaluate the influence of isomerism on skin effects. For this, gel cream formulations containing or not 0.05% tretinoin or 0.05% isotretinoin were applied in the dorsum of hairless mice, once a day for seven days. Histopathological evaluation, viable epidermal and horny layer thicknesses as well as the number of epidermal cell layers were determined. Our results showed that tretinoin and isotretinoin were effective in the enhancement of viable epidermis thickness and number of epidermal cell layers, suggesting that they could be used for stimulation of cellular renewal. However isomerism influenced skin effects since isotretinoin had more pronounced effects than tretinoin in viable epidermis. In addition only isotretinoin treatment enhanced horny layer thickness when compared to the gel cream treatment.

Pharmacokinetics of isotretinoin during repetitive dosing to patients.

PubMed

Brazzell, R K; Vane, F M; Ehmann, C W; Colburn, W A

1983-01-01

The multiple dose pharmacokinetics of isotretinoin and its major blood metabolite, 4-oxo-isotretinoin, were studied in 10 patients with cystic acne and 11 patients with various keratinization disorders. Blood samples were obtained at predetermined times following the first dose, interim doses and the final dose. Blood concentrations of isotretinoin and 4-oxo-isotretinoin were measured by a specific and sensitive HPLC method. A lag time was usually observed prior to the onset of absorption following oral administration of the drug in a soft elastic gelatin capsule. Absorption then proceeded rapidly and maximum blood concentrations usually occurred within 4 h of drug administration. The harmonic mean half-life for the elimination of isotretinoin by the cystic acne patients was approximately 10 h after the initial dose and did not change significantly following 25 days of 40 mg b.i.d. dosing. Steady-state blood concentrations remained relatively constant after the fifth day of dosing. The harmonic mean elimination half-life in the patients with various disorders of keratinization was about 16 h. The results of the 2 studies suggest that no significant changes in the pharmacokinetics of isotretinoin occur during multiple dosing and that the multiple dose pharmacokinetic profile is predictable and can be described using a linear pharmacokinetic model. This suggests that the steady-state concentrations of isotretinoin can be predicted from single dose data.

Free-Energy-Based Protein Design: Re-Engineering Cellular Retinoic Acid Binding Protein II Assisted by the Moveable-Type Approach.

PubMed

Zhong, Haizhen A; Santos, Elizabeth M; Vasileiou, Chrysoula; Zheng, Zheng; Geiger, James H; Borhan, Babak; Merz, Kenneth M

2018-03-14

How to fine-tune the binding free energy of a small-molecule to a receptor site by altering the amino acid residue composition is a key question in protein engineering. Indeed, the ultimate solution to this problem, to chemical accuracy (±1 kcal/mol), will result in profound and wide-ranging applications in protein design. Numerous tools have been developed to address this question using knowledge-based models to more computationally intensive molecular dynamics simulations-based free energy calculations, but while some success has been achieved there remains room for improvement in terms of overall accuracy and in the speed of the methodology. Here we report a fast, knowledge-based movable-type (MT)-based approach to estimate the absolute and relative free energy of binding as influenced by mutations in a small-molecule binding site in a protein. We retrospectively validate our approach using mutagenesis data for retinoic acid binding to the Cellular Retinoic Acid Binding Protein II (CRABPII) system and then make prospective predictions that are borne out experimentally. The overall performance of our approach is supported by its success in identifying mutants that show high or even sub-nano-molar binding affinities of retinoic acid to the CRABPII system.

Vitamin E supplementation does not prevent ethanol-reduced hepatic retinoic acid levels in rats

USDA-ARS?s Scientific Manuscript database

Chronic, excessive ethanol intake can increase retinoic acid (RA) catabolism by inducing cytochrome P450 2E1 (CYP2E1). Vitamin E (VE) is an antioxidant implicated in CYP2E1 inhibition. In the current study, we hypothesized that VE supplementation inhibits CYP2E1 and decreases RA catabolism, thereby ...

ALDH1A3 mutations cause recessive anophthalmia and microphthalmia.

PubMed

Fares-Taie, Lucas; Gerber, Sylvie; Chassaing, Nicolas; Clayton-Smith, Jill; Hanein, Sylvain; Silva, Eduardo; Serey, Margaux; Serre, Valérie; Gérard, Xavier; Baumann, Clarisse; Plessis, Ghislaine; Demeer, Bénédicte; Brétillon, Lionel; Bole, Christine; Nitschke, Patrick; Munnich, Arnold; Lyonnet, Stanislas; Calvas, Patrick; Kaplan, Josseline; Ragge, Nicola; Rozet, Jean-Michel

2013-02-07

Anophthalmia and microphthalmia (A/M) are early-eye-development anomalies resulting in absent or small ocular globes, respectively. A/M anomalies occur in syndromic or nonsyndromic forms. They are genetically heterogeneous, some mutations in some genes being responsible for both anophthalmia and microphthalmia. Using a combination of homozygosity mapping, exome sequencing, and Sanger sequencing, we identified homozygosity for one splice-site and two missense mutations in the gene encoding the A3 isoform of the aldehyde dehydrogenase 1 (ALDH1A3) in three consanguineous families segregating A/M with occasional orbital cystic, neurological, and cardiac anomalies. ALDH1A3 is a key enzyme in the formation of a retinoic acid gradient along the dorso-ventral axis during early eye development. Transitory expression of mutant ALDH1A3 open reading frames showed that both missense mutations reduce the accumulation of the enzyme, potentially leading to altered retinoic acid synthesis. Although the role of retinoic acid signaling in eye development is well established, our findings provide genetic evidence of a direct link between retinoic-acid-synthesis dysfunction and early-eye-development anomalies in humans. Copyright © 2013 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

RETINOIC ACID SYNTHESIS AND DEGRADATION

PubMed Central

Kedishvili, Natalia Y.

2017-01-01

Retinoic acid was identified as the biologically active form of vitamin A almost 70 years ago, but the exact enzymes and control mechanisms that regulate its biosynthesis and degradation are yet to be fully defined. The currently accepted model postulates that RA is produced in two sequential oxidative steps: first, retinol is oxidized reversibly to retinaldehyde, and then retinaldehyde is oxidized irreversibly to RA, which is inactivated by conversion to hydroxylated derivatives. This chapter describes the history, development and recent advances in our understanding of the enzymatic pathways and mechanisms that control the rate of RA production and degradation. Gene knockout studies provided strong evidence that the members of the short chain dehydrogenase reductase superfamily of proteins play indispensable roles in retinoic acid biosynthesis during development. Furthermore, recent finding that two of these proteins regulate the rate of retinoic acid biosynthesis by mutually activating each other provided a novel insight into the mechanism of this regulation. Despite significant progress made since the middle of the 20th century many unanswered questions still remain, and there is much to be learned, especially about trafficking of the hydrophobic retinoid substrates between membrane bound and cytosolic enzymes and the roles of the retinoid binding proteins. PMID:27830503

The Retinoid X Receptors and Their Ligands

PubMed Central

Dawson, Marcia I.; Xia, Zebin

2014-01-01

This chapter presents an overview of the current status of studies on the structural and molecular biology of the retinoid X receptor subtypes α, β, and γ (RXRs, NR2B1–3), their nuclear and cytoplasmic functions, post-transcriptional processing, and recently reported ligands. Points of interest are the different changes in the ligand-binding pocket induced by variously shaped agonists, the communication of the ligand–bound pocket with the coactivator binding surface and the heterodimerization interface, and recently identified ligands that are natural products, those that function as environmental toxins or drugs that had been originally designed to interact with other targets, as well as those that were deliberately designed as RXR-selective transcriptional agonists, synergists, or antagonists. Of these synthetic ligands, the general trend in design appears to be away from fully aromatic rigid structures to those containing partial elements of the flexible tetraene side chain of 9-cis-retinoic acid. PMID:22020178

Retinoic acid, hemin and hexamethylen bisacetamide interference with "in vitro" differentiation of chick embryo chondrocytes.

PubMed

Manduca, P; Abelmoschi, M L

1992-01-01

We have investigated the effect of all-trans Retinoic acid, and of substances (Hemine and Hexamethylene bisacetamide) which interfere with "in vitro" differentiation of mesenchyme derived cell lineages on the expression of specific markers of hyperthrophy in "in vitro" differentiating chick embryo chondrocytes. (Castagnola P., et al., 1986). Continuous treatment of chondrogenic cells in conditions allowing differentiation "in vitro" with Retinoic acid resulted in persistence of type I collagen synthesis and in lack of type X collagen and Ch 21 protein expression. Hemin treated cells secreted a reduced amount of type X collagen. HMBA treatment inhibited type X collagen expression and caused reduction of the ratio between type II collagen and Ch 21 synthesized. The data indicate an independent regulation of these markers during chondrocyte differentiation.

Fixed-Dose Combination Gel of Adapalene and Benzoyl Peroxide plus Doxycycline 100 mg versus Oral Isotretinoin for the Treatment of Severe Acne: Efficacy and Cost Analysis

PubMed Central

Penna, Pete; Meckfessel, Matthew H.; Preston, Norman

2014-01-01

Background Acne vulgaris is a chronic skin disease with a high prevalence. Left untreated or inadequately treated, acne vulgaris can lead to psychological and physical scarring, as well as to unnecessary medical expenses. Oral isotretinoin is an effective treatment for severe resistant nodular and conglobate acne vulgaris. A regimen consisting of a fixed-dose combination of adapalene and benzoyl peroxide gel, 0.1%/2.5% (A-BPO) with oral doxycycline 100 mg (A-BPO/D) has been demonstrated to be efficacious and well tolerated in patients with severe acne and may be an alternative to oral isotretinoin for some patients with severe acne. Objective The objective of this analysis was to compare the relative efficacy and associated costs of A-BPO/D versus oral isotretinoin. Methods In this analysis, comparisons of relative efficacy were made using previously published studies involving similar patient populations with severe acne that warrant the use of oral isotretinoin. The pricing for oral doxycycline and oral isotretinoin was estimated based on the maximum allowable cost from 9 states, and the pricing for A-BPO was calculated as the range between the average wholesale price and the wholesale acquisition cost. For this analysis, 2 treatment models were generated to compare costs: (1) a basic treatment model that examined the costs of an initial regimen of either A-BPO/D or oral isotretinoin without considering probable outcomes, and (2) a long-term model that factored in likely treatment outcomes and subsequent treatments into associated costs. The basic treatment model assumed that patients would be prescribed a single regimen of A-BPO/D for 12 weeks or oral isotretinoin for 20 weeks. The long-term model considered the probability of each treatment successfully managing patients' acne, as well as likely additional regimens of A-BPO monotherapy or an additional regimen of oral isotretinoin. As a result of different treatment durations, the costs for each treatment were normalized to weekly cost of treatment. Results Based on evidence from the published literature, patients treated with A-BPO/D would be expected to have an initial 72% reduction in inflammatory lesions, and patients treated with oral isotretinoin would have an 80% to 90% reduction of these lesions. The median weekly cost for the basic treatment model was $44 for A-BPO/D and $62 for oral isotretinoin. The weekly median costs for the long-term model were $44 for patients initially receiving a regimen of A-BPO/D followed by a maintenance regimen of A-BPO monotherapy and $50 for patients receiving an initial regimen of A-BPO/D who required a subsequent regimen of oral isotretinoin. The weekly cost for oral isotretinoin in the long-term model was $62. Conclusions The comparison of these 2 treatments demonstrated that they are both effective in treating severe acne, and that A-BPO/D was less expensive weekly than oral isotretinoin. These models show that A-BPO/D is safer than and is a more cost-effective alternative to oral isotretinoin for treating patients with severe acne vulgaris. PMID:24991389

Fixed-Dose Combination Gel of Adapalene and Benzoyl Peroxide plus Doxycycline 100 mg versus Oral Isotretinoin for the Treatment of Severe Acne: Efficacy and Cost Analysis.

PubMed

Penna, Pete; Meckfessel, Matthew H; Preston, Norman

2014-01-01

Acne vulgaris is a chronic skin disease with a high prevalence. Left untreated or inadequately treated, acne vulgaris can lead to psychological and physical scarring, as well as to unnecessary medical expenses. Oral isotretinoin is an effective treatment for severe resistant nodular and conglobate acne vulgaris. A regimen consisting of a fixed-dose combination of adapalene and benzoyl peroxide gel, 0.1%/2.5% (A-BPO) with oral doxycycline 100 mg (A-BPO/D) has been demonstrated to be efficacious and well tolerated in patients with severe acne and may be an alternative to oral isotretinoin for some patients with severe acne. The objective of this analysis was to compare the relative efficacy and associated costs of A-BPO/D versus oral isotretinoin. In this analysis, comparisons of relative efficacy were made using previously published studies involving similar patient populations with severe acne that warrant the use of oral isotretinoin. The pricing for oral doxycycline and oral isotretinoin was estimated based on the maximum allowable cost from 9 states, and the pricing for A-BPO was calculated as the range between the average wholesale price and the wholesale acquisition cost. For this analysis, 2 treatment models were generated to compare costs: (1) a basic treatment model that examined the costs of an initial regimen of either A-BPO/D or oral isotretinoin without considering probable outcomes, and (2) a long-term model that factored in likely treatment outcomes and subsequent treatments into associated costs. The basic treatment model assumed that patients would be prescribed a single regimen of A-BPO/D for 12 weeks or oral isotretinoin for 20 weeks. The long-term model considered the probability of each treatment successfully managing patients' acne, as well as likely additional regimens of A-BPO monotherapy or an additional regimen of oral isotretinoin. As a result of different treatment durations, the costs for each treatment were normalized to weekly cost of treatment. Based on evidence from the published literature, patients treated with A-BPO/D would be expected to have an initial 72% reduction in inflammatory lesions, and patients treated with oral isotretinoin would have an 80% to 90% reduction of these lesions. The median weekly cost for the basic treatment model was $44 for A-BPO/D and $62 for oral isotretinoin. The weekly median costs for the long-term model were $44 for patients initially receiving a regimen of A-BPO/D followed by a maintenance regimen of A-BPO monotherapy and $50 for patients receiving an initial regimen of A-BPO/D who required a subsequent regimen of oral isotretinoin. The weekly cost for oral isotretinoin in the long-term model was $62. The comparison of these 2 treatments demonstrated that they are both effective in treating severe acne, and that A-BPO/D was less expensive weekly than oral isotretinoin. These models show that A-BPO/D is safer than and is a more cost-effective alternative to oral isotretinoin for treating patients with severe acne vulgaris.

Analysis of fatty acid composition of anaerobic rumen fungi.

PubMed

Koppová, I; Novotná, Z; Strosová, L; Fliegerová, K

2008-01-01

The fatty acid (FA) composition of fresh mycelia of anaerobic rumen fungi was determined. The fatty acids methyl esters (FAME) of six strains belonging to four genera (Neocallimastix, Caecomyces, Orpinomyces, Anaeromyces) and one unknown strain were analyzed by gas chromatography. All studied fungi possess the same FAs but differences were found in their relative concentrations. The FA profile of anaerobic fungi comprises carbon chains of length ranging from 12 to 24; the most common fatty acids were stearic (C(18:0)), arachidic (C(20:0)), heneicosanoic (C(21:0)), behenic (C(22:0)), tricosanoic (C(23:0)) and lignoceric (C(24:0)) with relative amount representing >4% of total FA. Significant differences were determined for heptadecanoic, oleic, behenic and tricosanoic acids. Rumen anaerobic fungi can contain very long chain fatty acids; we found unsaturated fatty acids including cis-11-eicosenoic (C(20:1)), cis-11,14-eicosadienoic (C(20:2)), erucic (C(22:1n9)), cis-13,16-docosadienoic (C(22:2)) and nervonic (C(24:1)) acids in very small amounts but their presence seems to be unique for anaerobic fungi.

Low dose isotretinoin combined with tretinoin is effective to correct abnormalities of acne.

PubMed

Plewig, Gerd; Dressel, Heidrun; Pfleger, Maike; Michelsen, Silke; Kligman, Albert M

2004-01-01

Isotretinoin is well known in the therapy of acne papulopustulosa and acne conglobata. No study has investigated the pathophysiological changes of the skin of acne patients, especially when low dose oral isotretinoin is given in combination with topical tretinoin. 28 patients were treated for 6 months with oral isotretinoin. In the acne conglobata group (A-C) patients were treated with 10 mg (Group A) or 20 mg isotretinoin (Groups B, C) in combination with topical 0.05% tretinoin cream. Group C was treated the first 2 weeks with 0.05% betamethasone valerate cream instead of tretinoin cream. In the acne papulopustulosa group, the patients received 0.5 mg isotretinoin/kg bodyweight and 0.05% tretinoin cream, either alone (Group E), or with oral methylprednisolone during induction (Group D). Acne conglobata--A reduction of inflammatory lesion by 87-94% and of non-inflammatory lesions by 81-88% was achieved (Groups A-C). A reduction of sebaceous gland size by 35-58%, sebum production by 90-95%, follicular keratinization by 55-70% and Propionibacteria by 33-73% was seen (Groups B and C better than Group A). In Group A the amount of lipids was only reduced by 6%, in Group B by 35% and in Group C by 40%. Acne papulopustulosa--Sebum excretion rate and follicular keratinization were reduced in Group D by 89% and 50% respectively, with isotretinoin alone by 94% and 53%. The amount of lipids was reduced in Group D by 40% and in Group E by 21%. Because of the efficacy and cost-benefit relationship of isotretinoin in the treatment of acne compared to other therapeutic approaches, further use low dose isotretinoin in the described settings seems to justified.

UVA is the major contributor to the photodegradation of tretinoin and isotretinoin: implications for development of improved pharmaceutical formulations

PubMed Central

Tashtoush, Bassam M.; Jacobson, Elaine L.; Jacobson, Myron K.

2008-01-01

The chemical stability of tretinoin (RA) and isotretinoin (13RA) in ethanol and dermatological cream preparations exposed to solar simulated light (SSL), UVA, and visible light has been studied. Photostability was monitored by an HPLC method that allowed simultaneous analysis of RA and 13RA, thus allowing photodegradation due to isomerization to other retinoids and photolysis to non-retinoid products to be monitored. Both retinoids undergo both isomerization and photolysis following SSL, UVA and visible light exposure but RA is more sensitive to photodegradation than 13RA. Degradation of both retinoids by photolysis is considerably greater in cream formulations than in ethanol and the photodegradation follows second order kinetics. Rate constants and half-lives for degradation of RA and 13RA in ethanol solution and cream preparations subjected to different light sources are reported. The UVA component of SSL is the major contributor to photodegradation. Since UVA penetrates deeply into skin, our results suggest that photodegradation of RA may contribute to the photosensitivity associated with RA therapy. Our studies suggest that development of improved formulations and the use of effective UVA sunscreens may reduce the side effects of RA therapy. PMID:18093761

UVA is the major contributor to the photodegradation of tretinoin and isotretinoin: Implications for development of improved pharmaceutical formulations.

PubMed

Tashtoush, Bassam M; Jacobson, Elaine L; Jacobson, Myron K

2008-03-20

The chemical stability of tretinoin (RA) and isotretinoin (13RA) in ethanol and dermatological cream preparations exposed to solar simulated light (SSL), UVA, and visible light has been studied. Photostability was monitored by an HPLC method that allowed simultaneous analysis of RA and 13RA, thus allowing photodegradation due to isomerization to other retinoids and photolysis to non-retinoid products to be monitored. Both retinoids undergo both isomerization and photolysis following SSL, UVA and visible light exposure but RA is more sensitive to photodegradation than 13RA. Degradation of both retinoids by photolysis is considerably greater in cream formulations than in ethanol and the photodegradation follows second order kinetics. Rate constants and half-lives for degradation of RA and 13RA in ethanol solution and cream preparations subjected to different light sources are reported. The UVA component of SSL is the major contributor to photodegradation. Since UVA penetrates deeply into skin, our results suggest that photodegradation of RA may contribute to the photosensitivity associated with RA therapy. Our studies suggest that development of improved formulations and the use of effective UVA sunscreens may reduce the side effects of RA therapy.

Pharmacotherapy of retinal disease with visual cycle modulators.

PubMed

Hussain, Rehan M; Gregori, Ninel Z; Ciulla, Thomas A; Lam, Byron L

2018-04-01

Pharmacotherapy with visual cycle modulators (VCMs) is under investigation for retinitis pigmentosa (RP), Leber congenital amaurosis (LCA), Stargardt macular dystrophy (SMD) and nonexudative age-related macular degeneration (AMD), all blinding diseases that lack effective treatment options. Areas covered: The authors review investigational VCMs, including oral retinoids, 9-cis-retinyl-acetate (zuretinol) and 9-cis-β-carotene, which restore 11-cis-retinal levels in RP and LCA caused by LRAT and RPE65 gene mutations, and may improve visual acuity and visual fields. Therapies for SMD aiming to decrease accumulation of toxic Vitamin A dimers and lipofuscin in the retina and retinal pigment epithelium (RPE) include C20-D3-vitamin A (ALK-001), isotretinoin, VM200, emixustat, and A1120. Mouse models of SMD show promising data for these treatments, though proof of efficacy in humans is currently lacking. Fenretinide and emixustat are investigational VCMs for dry AMD, though neither has been shown to reduce geographic atrophy or improve vision in human trials. A1120 prevents retinol transport into the RPE and may spare the side effects typically seen in VCMs (nyctalopia and chromatopsia) per mouse studies. Expert opinion: Oral VCMs may be feasible treatment options for degenerative retinal diseases based on pre-clinical and some early clinical studies. Further trials are warranted to assess their efficacy and safety in humans.

Selective Cooperation between Fatty Acid Binding Proteins and Peroxisome Proliferator-Activated Receptors in Regulating Transcription

PubMed Central

Tan, Nguan-Soon; Shaw, Natacha S.; Vinckenbosch, Nicolas; Liu, Peng; Yasmin, Rubina; Desvergne, Béatrice; Wahli, Walter; Noy, Noa

2002-01-01

Lipophilic compounds such as retinoic acid and long-chain fatty acids regulate gene transcription by activating nuclear receptors such as retinoic acid receptors (RARs) and peroxisome proliferator-activated receptors (PPARs). These compounds also bind in cells to members of the family of intracellular lipid binding proteins, which includes cellular retinoic acid-binding proteins (CRABPs) and fatty acid binding proteins (FABPs). We previously reported that CRABP-II enhances the transcriptional activity of RAR by directly targeting retinoic acid to the receptor. Here, potential functional cooperation between FABPs and PPARs in regulating the transcriptional activities of their common ligands was investigated. We show that adipocyte FABP and keratinocyte FABP (A-FABP and K-FABP, respectively) selectively enhance the activities of PPARγ and PPARβ, respectively, and that these FABPs massively relocate to the nucleus in response to selective ligands for the PPAR isotype which they activate. We show further that A-FABP and K-FABP interact directly with PPARγ and PPARβ and that they do so in a receptor- and ligand-selective manner. Finally, the data demonstrate that the presence of high levels of K-FABP in keratinocytes is essential for PPARβ-mediated induction of differentiation of these cells. Taken together, the data establish that A-FABP and K-FABP govern the transcriptional activities of their ligands by targeting them to cognate PPARs in the nucleus, thereby enabling PPARs to exert their biological functions. PMID:12077340

Formation and evolution of monoepoxy fatty acids in thermoxidized olive and sunflower oils and quantitation in used frying oils from restaurants and fried-food outlets.

PubMed

Velasco, Joaquín; Marmesat, Susana; Bordeaux, Olivier; Márquez-Ruiz, Gloria; Dobarganes, Carmen

2004-07-14

The formation and evolution of monoepoxy fatty acids, arising from oleic and linoleic acids, were investigated in olive oil and conventional sunflower oil, representatives of monounsaturated and polyunsaturated oils, respectively, during thermoxidation at 180 degrees C for 5, 10, and 15 h. Six monoepoxy fatty acids, cis-9,10- and trans-9,10-epoxystearate, arising from oleic acid, and cis-9,10-, trans-9,10-, cis-12,13-, and trans-12,13-epoxyoleate, arising from linoleic acid, were analyzed by gas chromatography after oil derivatization to fatty acid methyl esters. Considerable amounts, ranging from 4.29 to 14.24 mg/g of oil in olive oil and from 5.10 to 9.44 mg/g of oil in sunflower oil, were found after the heating periods assayed. Results showed that the monoepoxides quantitated constituted a major group among the oxidized fatty acid monomers formed at high temperature. For similar levels of degradation, higher contents of the monoepoxides were found in olive oil than in sunflower oil. Ten used frying oils from restaurants and fried-food outlets in Spain were analyzed to determine the contents of the monoepoxides in real frying oil samples. Levels ranged from 3.37 to 14.42 mg/g of oil. Results show that, for similar degradation levels, the monoepoxides were more abundant in the monounsaturated oils than in the polyunsaturated oils.

EXPRESSION OF EGFR AND ITS LIGANDS IN RESPONSE TO TCDD OR RETINOIC ACID IN EGF AND TGFALPHA KO FETAL MOUSE PALATE

EPA Science Inventory

EXPRESSION OF EGFR AND ITS LIGANDS IN RESPONSE TO TCDD OR RETINOIC ACID IN EGF AND TGF" KO FETAL MOUSE PALATE. Abbott, Barbara D.1; Boyd, Hadiya2; Wood, Carmen1; Held, Gary1. 1.EPA, ORD, NHEERL, RTD, US EPA, Research Triangle Park, NC, USA. 2MARC Program, NCCU, Durham, NC, USA. <...

Cloning of a cDNA encoding rat aldehyde dehydrogenase with high activity for retinal oxidation.

PubMed

Bhat, P V; Labrecque, J; Boutin, J M; Lacroix, A; Yoshida, A

1995-12-12

Retinoic acid (RA), an important regulator of cell differentiation, is biosynthesized from retinol via retinal by a two-step oxidation process. We previously reported the purification and partial amino acid (aa) sequence of a rat kidney aldehyde dehydrogenase (ALDH) isozyme that catalyzed the oxidation of 9-cis and all-trans retinal to corresponding RA with high efficiency [Labrecque et al. Biochem. J. 305 (1995) 681-684]. A rat kidney cDNA library was screened using a 291-bp PCR product generated from total kidney RNA using a pair of oligodeoxyribonucleotide primers matched with the aa sequence. The full-length rat kidney ALDH cDNA contains a 2315-bp (501 aa) open reading frame (ORF). The aa sequence of rat kidney ALDH is 89, 96 and 87% identical to that of the rat cytosolic ALDH, the mouse cytosolic ALDH and human cytosolic ALDH, respectively. Northern blot and RT-PCR-mediated analysis demonstrated that rat kidney ALDH is strongly expressed in kidney, lung, testis, intestine, stomach and trachea, but weakly in the liver.

The comparison of the rejuvenation effects on the skin of Wistar rats between 10600 nm CO2 fractional laser and retinoic acid.

PubMed

Qu, Y; Ma, W-Y; Sun, Q

2017-04-01

The fractional laser and topical retinoic acid treatment have been applied for skin rejuvenation; however, the possible molecular mechanism of promoting remodeling of dermis is not clearly. Here we aimed to compare the effects of 10600 nm CO2 fractional laser and topical retinoic acid formulation on the skin collagen proliferation of Wistar rats, and to further explore the possible molecular mechanism of promoting remodeling of dermis. The hair on the back of Wistar rats was removed, and the back was divided equally into four regions with the cross-streaking method: A (the control group), B (the retinoic acid group), C (retinoic acid and fractional laser combination treatment group), and D (the fractional laser group). Specimens were collected at 3rd day and in 1-8 weeks after CO2 fractional laser irradiation; then they were used for detection of the changes of dermis thickness and content of hydroxyproline in the four regions of the rats' back. Real-time PCR method was used to detect the dynamic changes of the expression level of type III procollagen mRNA and the expression levels of miR-29a, Akt and transforming growth factor-β (TGF-β) mRNA at 3rd week in the skin tissue of Wistar rats. The thickness of dermis, content of hydroxyproline and expression level of type III procollagen mRNA in the treatment groups (B, C, and D) were found all significantly increased compared with those in the control group (A) (p<0.05); at 3rd week, up-regulation of Akt and TGF-β mRNA expression and down-regulation of miR-29a mRNA expression were observed in the treatment groups (B, C, and D). The difference in the combination treatment group (C) was the most significant (p<0.05). These results demonstrate that retinoic acid formulation and CO2 fractional laser both can promote collagen proliferation and reconstruction, with the skin rejuvenation efficacy in group C > group D > group B. miR-29a/Akt/TGF-β signal pathways may play a certain role in the promotion of collagen synthesis and proliferation.

Synergistic growth inhibition by acyclic retinoid and vitamin K2 in human hepatocellular carcinoma cells.

PubMed

Kanamori, Toh; Shimizu, Masahito; Okuno, Masataka; Matsushima-Nishiwaki, Rie; Tsurumi, Hisashi; Kojima, Soichi; Moriwaki, Hisataka

2007-03-01

Hepatocellular carcinoma (HCC) is one of the most prevalent cancers worldwide. However, effective chemopreventive and chemotherapeutic agents for this cancer have not yet been developed. In clinical trials acyclic retinoid (ACR) and vitamin K(2) (VK(2)) decreased the recurrence rate of HCC. In the present study we examined the possible combined effects of ACR or another retinoid 9-cis retinoic acid (9cRA) plus VK(2) in the HuH7 human HCC cell line. We found that the combination of 1.0 microM ACR or 1.0 microM 9cRA plus 10 microM VK(2) synergistically inhibited the growth of HuH7 cells without affecting the growth of Hc normal human hepatocytes. The combined treatment with ACR plus VK(2) also acted synergistically to induce apoptosis in HuH7 cells. Treatment with VK(2) alone inhibited phosphorylation of the retinoid X receptor (RXR)alpha protein, which is regarded as a critical factor for liver carcinogenesis, through inhibition of Ras activation and extracellular signal-regulated kinase phosphorylation. Moreover, the inhibition of RXRalpha phosphorylation by VK(2) was enhanced when the cells were cotreated with ACR. The combination of retinoids plus VK(2) markedly increased both the retinoic acid receptor responsive element and retinoid X receptor responsive element promoter activities in HuH7 cells. Our results suggest that retinoids (especially ACR) and VK(2) cooperatively inhibit activation of the Ras/MAPK signaling pathway, subsequently inhibiting the phosphorylation of RXRalpha and the growth of HCC cells. This combination might therefore be effective for the chemoprevention and chemotherapy of HCC.

Cryptic Patterning of Avian Skin Confers a Developmental Facility for Loss of Neck Feathering

PubMed Central

Mou, Chunyan; Pitel, Frederique; Gourichon, David; Vignoles, Florence; Tzika, Athanasia; Tato, Patricia; Yu, Le; Burt, Dave W.; Bed'hom, Bertrand; Tixier-Boichard, Michele; Painter, Kevin J.; Headon, Denis J.

2011-01-01

Vertebrate skin is characterized by its patterned array of appendages, whether feathers, hairs, or scales. In avian skin the distribution of feathers occurs on two distinct spatial levels. Grouping of feathers within discrete tracts, with bare skin lying between the tracts, is termed the macropattern, while the smaller scale periodic spacing between individual feathers is referred to as the micropattern. The degree of integration between the patterning mechanisms that operate on these two scales during development and the mechanisms underlying the remarkable evolvability of skin macropatterns are unknown. A striking example of macropattern variation is the convergent loss of neck feathering in multiple species, a trait associated with heat tolerance in both wild and domestic birds. In chicken, a mutation called Naked neck is characterized by a reduction of body feathering and completely bare neck. Here we perform genetic fine mapping of the causative region and identify a large insertion associated with the Naked neck trait. A strong candidate gene in the critical interval, BMP12/GDF7, displays markedly elevated expression in Naked neck embryonic skin due to a cis-regulatory effect of the causative mutation. BMP family members inhibit embryonic feather formation by acting in a reaction-diffusion mechanism, and we find that selective production of retinoic acid by neck skin potentiates BMP signaling, making neck skin more sensitive than body skin to suppression of feather development. This selective production of retinoic acid by neck skin constitutes a cryptic pattern as its effects on feathering are not revealed until gross BMP levels are altered. This developmental modularity of neck and body skin allows simple quantitative changes in BMP levels to produce a sparsely feathered or bare neck while maintaining robust feather patterning on the body. PMID:21423653

Local sources of retinoic acid coincide with retinoid-mediated transgene activity during embryonic development.

PubMed Central

Colbert, M C; Linney, E; LaMantia, A S

1993-01-01

We have assessed whether retinoic acid (RA) comes from local sources or is available widely to activate gene expression in embryos. We used an RA-responsive indicator cell line, L-C2A5, to localize RA sources. In these cells, an RA-sensitive promoter/lacZ reporter construct used previously by us to produce indicator transgenic mice is induced globally by RA in medium or locally by RA released at physiological concentrations (1 nM) from AG-1X2 resin beads. Furthermore, the cells are differentially responsive to the 9-cis and all-trans isomers of RA at low concentrations. Indicator transgenic mice with the same promoter/reporter construct were used to identify regions of RA-mediated gene activation. There are distinct domains of lacZ expression in the cervical and lumbar spinal cords of embryonic indicator mice. This pattern might reflect localized RA sources or restricted spatial and temporal expression of RA receptors, binding proteins, or other factors. To resolve this issue we compared the pattern of transgene activation in indicator cell monolayers cocultured with normal embryonic spinal cords with that in transgenic spinal cords. The explants induced reporter gene expression in L-C2A5 monolayers in a pattern identical to that in transgenic mice: alar regions of the cervical and lumbar cord were positive whereas those in the thoracic and sacral regions were not. We conclude that restricted sources of RA in the developing spinal cord mediate the local activation of RA-inducible genes. Thus, region-specific gene activation in embryos can be mediated by precisely localized sources of inductive molecules like RA. Images Fig. 1 Fig. 2 Fig. 3 PMID:8341670

Unique occurrence of unusual fatty acids and their industrial utilization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hosamani, K.M.

1996-01-01

Ebenaceae plant family consists of 7 genera and more than 320 species. The present investigation describes the unique occurrence of hitherto unknown 9-keto-cis-13-octadecenoic acid (29.0%) and the cyclopropenoid fatty acids (malvalic acid 12.7% and sterculic acid 8.7%) in the seed oil of Diospyros melanoxylon as well as in the Ebenaceae plant family. Other normal fatty acids are also detected. The identification and characterization were based on FTIR, {sup 1}H NMR, {sup 13}C NMR, MS, and GLC techniques and chemical degradations.

Extraction of oil from Euphorbia Lagascae seeds by screw pressing

USDA-ARS?s Scientific Manuscript database

Euphorbia lagascae (Spreng.) is a drought tolerant plant native to Spain. Euphorbia seeds contain 45-50% oil with 60-65% of its fatty acids as vernolic (12S,13R-epoxy-cis-9-octadecenoic) acid. Vernolic acid has wide applications in paints and coatings, plasticizers, adhesives, polymers, and lubrican...

Interleukin-33-Activated Islet-Resident Innate Lymphoid Cells Promote Insulin Secretion through Myeloid Cell Retinoic Acid Production.

PubMed

Dalmas, Elise; Lehmann, Frank M; Dror, Erez; Wueest, Stephan; Thienel, Constanze; Borsigova, Marcela; Stawiski, Marc; Traunecker, Emmanuel; Lucchini, Fabrizio C; Dapito, Dianne H; Kallert, Sandra M; Guigas, Bruno; Pattou, Francois; Kerr-Conte, Julie; Maechler, Pierre; Girard, Jean-Philippe; Konrad, Daniel; Wolfrum, Christian; Böni-Schnetzler, Marianne; Finke, Daniela; Donath, Marc Y

2017-11-21

Pancreatic-islet inflammation contributes to the failure of β cell insulin secretion during obesity and type 2 diabetes. However, little is known about the nature and function of resident immune cells in this context or in homeostasis. Here we show that interleukin (IL)-33 was produced by islet mesenchymal cells and enhanced by a diabetes milieu (glucose, IL-1β, and palmitate). IL-33 promoted β cell function through islet-resident group 2 innate lymphoid cells (ILC2s) that elicited retinoic acid (RA)-producing capacities in macrophages and dendritic cells via the secretion of IL-13 and colony-stimulating factor 2. In turn, local RA signaled to the β cells to increase insulin secretion. This IL-33-ILC2 axis was activated after acute β cell stress but was defective during chronic obesity. Accordingly, IL-33 injections rescued islet function in obese mice. Our findings provide evidence that an immunometabolic crosstalk between islet-derived IL-33, ILC2s, and myeloid cells fosters insulin secretion. Copyright © 2017 Elsevier Inc. All rights reserved.

Picolinic and isonicotinic acids: a Fourier transform microwave spectroscopy study.

PubMed

Peña, Isabel; Varela, Marcelino; Franco, Vanina G; López, Juan C; Cabezas, Carlos; Alonso, José L

2014-12-04

The rotational spectra of laser ablated picolinic and isonicotinic acids have been studied using broadband chirped pulse (CP-FTMW) and narrowband molecular beam (MB-FTMW) Fourier transform microwave spectroscopies. Two conformers of picolinic acid, s-cis-I and s-cis-II, and one conformer of isonicotinic acid have been identified through the analysis of their rotational spectra. The values of the inertial defect and the quadrupole coupling constants obtained for the most stable s-cis-I conformer of picolinic acid, evidence the formation of an O-H···N hydrogen bond between the acid group and the endocyclic N atom. The stabilization provided by this hydrogen bond compensates the destabilization energy due to the adoption of a -COOH trans configuration in this conformer. Its rs structure has been derived from the rotational spectra of several (13)C, (15)N, and (18)O species observed in their natural abundances. Mesomeric effects have been revealed by comparing the experimental values of the (14)N nuclear quadrupole coupling constants in the isomeric series of picolinic, isonicotinic, and nicotinic acids.

Activation of the kinase activity of ATM by retinoic acid is required for CREB-dependent differentiation of neuroblastoma cells.

PubMed

Fernandes, Norvin D; Sun, Yingli; Price, Brendan D

2007-06-01

The ATM protein kinase is mutated in ataxia telangiectasia, a genetic disease characterized by defective DNA repair, neurodegeneration, and growth factor signaling defects. The activity of ATM kinase is activated by DNA damage, and this activation is required for cells to survive genotoxic events. In addition to this well characterized role in DNA repair, we now demonstrate a novel role for ATM in the retinoic acid (RA)-induced differentiation of SH-SY5Y neuroblastoma cells into post-mitotic, neuronal-like cells. RA rapidly activates the activity of ATM kinase, leading to the ATM-dependent phosphorylation of the CREB protein, extrusion of neuritic processes, and differentiation of SH-SY5Y cells into neuronal-like cells. When ATM protein expression was suppressed by short hairpin RNA, the ATM-dependent phosphorylation of CREB was blocked. Furthermore, ATM-negative cells failed to differentiate into neuronal-like cells when exposed to retinoic acid; instead, they underwent cell death. Expression of a constitutively active CREBVP16 construct, or exposure to forskolin to induce CREB phosphorylation, rescued ATM negative cells and restored differentiation. Furthermore, when dominant negative CREB proteins with mutations in either the CREB phosphorylation site (CREBS133A) or the DNA binding domain (KCREB) were introduced into SH-SY5Y cells, retinoic acid-induced differentiation was blocked and the cells underwent cell death. The results demonstrate that ATM is required for the retinoic acid-induced differentiation of SH-SY5Y cells through the ATM dependent-phosphorylation of serine 133 of CREB. These results therefore define a novel mechanism for activation of the activity of ATM kinase by RA, and implicate ATM in the regulation of CREB function during RA-induced differentiation.

Azadirachtin Interacts with Retinoic Acid Receptors and Inhibits Retinoic Acid-mediated Biological Responses*

PubMed Central

Thoh, Maikho; Babajan, Banaganapalli; Raghavendra, Pongali B.; Sureshkumar, Chitta; Manna, Sunil K.

2011-01-01

Considering the role of retinoids in regulation of more than 500 genes involved in cell cycle and growth arrest, a detailed understanding of the mechanism and its regulation is useful for therapy. The extract of the medicinal plant Neem (Azadirachta indica) is used against several ailments especially for anti-inflammatory, anti-itching, spermicidal, anticancer, and insecticidal activities. In this report we prove the detailed mechanism on the regulation of retinoic acid-mediated cell signaling by azadirachtin, active components of neem extract. Azadirachtin repressed all trans-retinoic acid (ATRA)-mediated nuclear transcription factor κB (NF-κB) activation, not the DNA binding but the NF-κB-dependent gene expression. It did not inhibit IκBα degradation, IκBα kinase activity, or p65 phosphorylation and its nuclear translocation but inhibited NF-κB-dependent reporter gene expression. Azadirachtin inhibited TRAF6-mediated, but not TRAF2-mediated NF-κB activation. It inhibited ATRA-induced Sp1 and CREB (cAMP-response element-binding protein) DNA binding. Azadirachtin inhibited ATRA binding with retinoid receptors, which is supported by biochemical and in silico evidences. Azadirachtin showed strong interaction with retinoid receptors. It suppressed ATRA-mediated removal of retinoid receptors, bound with DNA by inhibiting ATRA binding to its receptors. Overall, our data suggest that azadirachtin interacts with retinoic acid receptors and suppresses ATRA binding, inhibits falling off the receptors, and activates transcription factors like CREB, Sp1, NF-κB, etc. Thus, azadirachtin exerts anti-inflammatory and anti-metastatic responses by a novel pathway that would be beneficial for further anti-inflammatory and anti-cancer therapies. PMID:21127062

Lipocalin 2, a Regulator of Retinoid Homeostasis and Retinoid-mediated Thermogenic Activation in Adipose Tissue*

PubMed Central

Guo, Hong; Foncea, Rocio; O'Byrne, Sheila M.; Jiang, Hongfeng; Zhang, Yuanyuan; Deis, Jessica A.; Blaner, William S.; Bernlohr, David A.; Chen, Xiaoli

2016-01-01

We have recently characterized the role of lipocalin 2 (Lcn2) as a new adipose-derived cytokine in the regulation of adaptive thermogenesis via a non-adrenergic pathway. Herein, we explored a potential non-adrenergic mechanism by which Lcn2 regulates thermogenesis and lipid metabolism. We found that Lcn2 is a retinoic acid target gene, and retinoic acid concurrently stimulated UCP1 and Lcn2 expression in adipocytes. Lcn2 KO mice exhibited a blunted effect of all-trans-retinoic acid (ATRA) on body weight and fat mass, lipid metabolism, and retinoic acid signaling pathway activation in adipose tissue under the high fat diet-induced obese condition. We further demonstrated that Lcn2 is required for the full action of ATRA on the induction of UCP1 and PGC-1α expression in brown adipocytes and the restoration of cold intolerance in Lcn2 KO mice. Interestingly, we discovered that Lcn2 KO mice have decreased levels of retinoic acid and retinol in adipose tissue. The protein levels of STRA6 responsible for retinol uptake were significantly decreased in adipose tissue. The retinol transporter RBP4 was increased in adipose tissue but decreased in the circulation, suggesting the impairment of RBP4 secretion in Lcn2 KO adipose tissue. Moreover, Lcn2 deficiency abolished the ATRA effect on RBP4 expression in adipocytes. All the data suggest that the decreased retinoid level and action are associated with impaired retinol transport and storage in adipose tissue in Lcn2 KO mice. We conclude that Lcn2 plays a critical role in regulating metabolic homeostasis of retinoids and retinoid-mediated thermogenesis in adipose tissue. PMID:27008859

[Isotretinoin embryopathy: An entity that can be avoided].

PubMed

Cammarata-Scalisi, Francisco; Nieves, Dairelis; Avendaño, Andrea; Lacruz-Rengel, María A; Alviárez, Karelys; Dávila, Francys; Yavuz, Izzet; Callea, Michele

2018-04-01

Isotretinoin is the most effective drug in the treatment of severe recalcitrant nodulocystic acne. However, treatment with this drug is associated with adverse effects, the most severe being teratogenesis. It has been estimated that 40% of pregnancies exposed to isotretinoin present spontaneous abortion and 35% develop embryopathy. We present the case of a newborn with a history of prenatal exposure to isotretinoin, a clinical entity that can be avoided, with severe congenital defects in the central nervous system and important facial dysmorphisms, with unfavorable clinical course. Sociedad Argentina de Pediatría.

Recalcitrant Nodulocystic Acne in Black Americans: Treatment With Isotretinoin

PubMed Central

Kelly, A. Paul; Sampson, Darlene D.

1987-01-01

The beneficial effects of isotretinoin (Accutane) on severe nodulocystic acne and significant clinical improvement with prolonged remission are well documented in the literature; however, the subjects in these clinical studies are invariably white. The purpose of this study was to evaluate the response of black patients with recalcitrant nodulocystic acne to isotretinoin treatment. Ten black patients, ranging in age from 17 to 34 years, were treated for nodulocystic acne with 1 mg/kg/d of isotretinoin for 20 weeks and followed for an additional six months. Of the ten patients, eight adhered to the treatment regimen and were still in remission six months after completion of isotretinoin therapy. The differences and similarities seen between black patients and white patients with nodulocystic acne are discussed. ImagesFigure 1Figure 2Figure 3 PMID:2963137

Pediatric Phase I Trial and Pharmacokinetic Study of Vorinostat: A Children's Oncology Group Phase I Consortium Report

PubMed Central

Fouladi, Maryam; Park, Julie R.; Stewart, Clinton F.; Gilbertson, Richard J.; Schaiquevich, Paula; Sun, Junfeng; Reid, Joel M.; Ames, Matthew M.; Speights, Roseanne; Ingle, Ashish M.; Zwiebel, James; Blaney, Susan M.; Adamson, Peter C.

2010-01-01

Purpose The purpose of this study was to determine the maximum-tolerated dose (MTD), dose-limiting toxicities (DLT), and pharmacokinetics of vorinostat administered as a single agent and in combination 13-cis retinoic acid (13cRA) in children with refractory solid tumors; to evaluate the tolerability of the solid tumor MTD in children with refractory leukemias; and to characterize the pharmacokinetics of a vorinostat suspension in children. Patients and Methods Vorinostat was administered orally daily starting at 180 mg/m2/d with escalations planned in 30% increments. Pharmacokinetic studies were performed with the initial dose. Acetyl-histone (H3) accumulation was assessed by Western blotting of peripheral blood mononuclear cells (PBMC). Results Sixty-four patients were enrolled on this multipart trial. In patients with solid tumors, the MTD was 230 mg/m2/d with dose-limiting neutropenia, thrombocytopenia, and hypokalemia at 300 mg/m2/d. DLTs observed with the combination of 13cRA and vorinostat included thrombocytopenia, neutropenia, anorexia, and hypertriglyceridemia, resulting in a MTD of vorinostat 180 mg/m2/d 4 times per week and 13cRA 80 mg/m2/dose twice per day, days 1 through 14 every 28 days. Wide interpatient variability was noted in vorinostat disposition, with area under the concentration-time curves at 230 mg/m2/d for the capsule (range, 1,415 to 9,291 ng/mL × hr) and oral suspension (range, 1,186 to 4,780 ng/mL × hr). Significant accumulation of acetylated H3 histone in PBMC was observed after administration of vorinostat, particularly at higher doses. One patient with neuroblastoma experienced a complete response to the combination. Conclusion In children with recurrent solid tumors, vorinostat is well-tolerated at 230 mg/m2/d, with a modest dose reduction being required when combining vorinostat with 13cRA. Drug disposition is similar to that observed in adults. PMID:20606092

Berberine binds RXRα to suppress β-catenin signaling in colon cancer cells.

PubMed

Ruan, H; Zhan, Y Y; Hou, J; Xu, B; Chen, B; Tian, Y; Wu, D; Zhao, Y; Zhang, Y; Chen, X; Mi, P; Zhang, L; Zhang, S; Wang, X; Cao, H; Zhang, W; Wang, H; Li, H; Su, Y; Zhang, X K; Hu, T

2017-12-14

Berberine, an isoquinoline alkaloid, is a traditional oriental medicine used to treat diarrhea and gastroenteritis. Recently, we reported that it could inhibit the growth of intestinal polyp in animals and in patients with the familial adenomatous polyposis by downregulating β-catenin signaling. However, the intracellular target mediating the effects of berberine remains elusive. Here, we provide evidence that berberine inhibits β-catenin function via directly binding to a unique region comprising residues Gln275, Arg316 and Arg371 in nuclear receptor retinoid X receptor alpha (RXRα), where berberine concomitantly binding to and synergistically activating RXRα with 9-cis-retinoic acid (9-cis-RA), a natural ligand binding to the classical ligand-binding pocket of RXRα. Berberine binding promotes RXRα interaction with nuclear β-catenin, leading to c-Cbl mediated degradation of β-catenin, and consequently inhibits the proliferation of colon cancer cells. Furthermore, berberine suppresses the growth of human colon carcinoma xenograft in nude mice in an RXRα-dependent manner. Together, our study not only identifies RXRα as a direct protein target for berberine but also dissects their binding mode and validates that berberine indeed suppresses β-catenin signaling and cell growth in colon cancer via binding RXRα, which provide new strategies for the design of new RXRα-based antitumor agents and drug combinations.

Berberine binds RXRα to suppress β-catenin signaling in colon cancer cells

PubMed Central

Ruan, H; Zhan, Y Y; Hou, J; Xu, B; Chen, B; Tian, Y; Wu, D; Zhao, Y; Zhang, Y; Chen, X; Mi, P; Zhang, L; Zhang, S; Wang, X; Cao, H; Zhang, W; Wang, H; Li, H; Su, Y; Zhang, X K; Hu, T

2017-01-01

Berberine, an isoquinoline alkaloid, is a traditional oriental medicine used to treat diarrhea and gastroenteritis. Recently, we reported that it could inhibit the growth of intestinal polyp in animals and in patients with the familial adenomatous polyposis by downregulating β-catenin signaling. However, the intracellular target mediating the effects of berberine remains elusive. Here, we provide evidence that berberine inhibits β-catenin function via directly binding to a unique region comprising residues Gln275, Arg316 and Arg371 in nuclear receptor retinoid X receptor alpha (RXRα), where berberine concomitantly binding to and synergistically activating RXRα with 9-cis-retinoic acid (9-cis-RA), a natural ligand binding to the classical ligand-binding pocket of RXRα. Berberine binding promotes RXRα interaction with nuclear β-catenin, leading to c-Cbl mediated degradation of β-catenin, and consequently inhibits the proliferation of colon cancer cells. Furthermore, berberine suppresses the growth of human colon carcinoma xenograft in nude mice in an RXRα-dependent manner. Together, our study not only identifies RXRα as a direct protein target for berberine but also dissects their binding mode and validates that berberine indeed suppresses β-catenin signaling and cell growth in colon cancer via binding RXRα, which provide new strategies for the design of new RXRα-based antitumor agents and drug combinations. PMID:28846104

Conjugated fatty acid synthesis: residues 111 and 115 influence product partitioning of Momordica charantia conjugase.

PubMed

Rawat, Richa; Yu, Xiao-Hong; Sweet, Marie; Shanklin, John

2012-05-11

Conjugated linolenic acids (CLNs), 18:3 Δ(9,11,13), lack the methylene groups found between the double bonds of linolenic acid (18:3 Δ(9,12,15)). CLNs are produced by conjugase enzymes that are homologs of the oleate desaturases FAD2. The goal of this study was to map the domain(s) within the Momordica charantia conjugase (FADX) responsible for CLN formation. To achieve this, a series of Momordica FADX-Arabidopsis FAD2 chimeras were expressed in the Arabidopsis fad3fae1 mutant, and the transformed seeds were analyzed for the accumulation of CLN. These experiments identified helix 2 and the first histidine box as a determinant of conjugase product partitioning into punicic acid (18:3 Δ(9cis,11trans,13cis)) or α-eleostearic acid (18:3 Δ(9cis,11trans,13trans)). This was confirmed by analysis of a FADX mutant containing six substitutions in which the sequence of helix 2 and first histidine box was converted to that of FAD2. Each of the six FAD2 substitutions was individually converted back to the FADX equivalent identifying residues 111 and 115, adjacent to the first histidine box, as key determinants of conjugase product partitioning. Additionally, expression of FADX G111V and FADX G111V/D115E resulted in an approximate doubling of eleostearic acid accumulation to 20.4% and 21.2%, respectively, compared with 9.9% upon expression of the native Momordica FADX. Like the Momordica conjugase, FADX G111V and FADX D115E produced predominantly α-eleostearic acid and little punicic acid, but the FADX G111V/D115E double mutant produced approximately equal amounts of α-eleostearic acid and its isomer, punicic acid, implicating an interactive effect of residues 111 and 115 in punicic acid formation.

All-Trans Retinoic Acid-Induced Deficiency of the Wnt/β-Catenin Pathway Enhances Hepatic Carcinoma Stem Cell Differentiation

PubMed Central

Zhang, Xia; Bai, Jianhua; Chen, Gang; Li, Li; Li, Meizhang

2015-01-01

Retinoic acid (RA) is an important biological signal that directly differentiates cells during embryonic development and tumorigenesis. However, the molecular mechanism of RA-mediated differentiation in hepatic cancer stem cells (hCSCs) is not well understood. In this study, we found that mRNA expressions of RA-biosynthesis-related dehydrogenases were highly expressed in hepatocellular carcinoma. All-trans retinoic acid (ATRA) differentiated hCSCs through inhibiting the function of β-catenin in vitro. ATRA also inhibited the function of PI3K-AKT and enhanced GSK-3β-dependent degradation of phosphorylated β-catenin. Furthermore, ATRA and β-catenin silencing both increased hCSC sensitivity to docetaxel treatment. Our results suggest that targeting β-catenin will provide extra benefits for ATRA-mediated treatment of hepatic cancer patients. PMID:26571119

Cloning of a gene (RIG-G) associated with retinoic acid-induced differentiation of acute promyelocytic leukemia cells and representing a new member of a family of interferon-stimulated genes

PubMed Central

Yu, Man; Tong, Jian-Hua; Mao, Mao; Kan, Li-Xin; Liu, Meng-Min; Sun, Yi-Wu; Fu, Gang; Jing, Yong-Kui; Yu, Long; Lepaslier, Denis; Lanotte, Michel; Wang, Zhen-Yi; Chen, Zhu; Waxman, Samuel; Wang, Ya-Xin; Tan, Jia-Zhen; Chen, Sai-Juan

1997-01-01

In a cell line (NB4) derived from a patient with acute promyelocytic leukemia, all-trans-retinoic acid (ATRA) and interferon (IFN) induce the expression of a novel gene we call RIG-G (for retinoic acid-induced gene G). This gene codes for a 58-kDa protein containing 490 amino acids with several potential sites for post-translational modification. In untreated NB4 cells, the expression of RIG-G is undetectable. ATRA treatment induces the transcriptional expression of RIG-G relatively late (12–24 hr) in a protein synthesis-dependent manner, whereas IFN-α induces its expression early (30 min to 3 hr). Database search has revealed a high-level homology between RIG-G and several IFN-stimulated genes in human (ISG54K, ISG56K, and IFN-inducible and retinoic acid-inducible 58K gene) and some other species, defining a well conserved gene family. The gene is composed of two exons and has been mapped by fluorescence in situ hybridization to chromosome 10q24, where two other human IFN-stimulated gene members are localized. A synergistic induction of RIG-G expression in NB4 cells by combined treatment with ATRA and IFNs suggests that a collaboration exists between their respective signaling pathways. PMID:9207104

Expression analysis of some genes regulated by retinoic acid in controls and triadimefon-exposed embryos: is the amphibian Xenopus laevis a suitable model for gene-based comparative teratology?

PubMed

Di Renzo, Francesca; Rossi, Federica; Bacchetta, Renato; Prati, Mariangela; Giavini, Erminio; Menegola, Elena

2011-06-01

The use of nonmammal models in teratological studies is a matter of debate and seems to be justified if the embryotoxic mechanism involves conserved processes. Published data on mammals and Xenopus laevis suggest that azoles are teratogenic by altering the endogenous concentration of retinoic acid (RA). The expression of some genes (Shh, Ptch-1, Gsc, and Msx2) controlled by retinoic acid is downregulated in rat embryos exposed at the phylotypic stage to the triazole triadimefon (FON). In order to propose X. laevis as a model for gene-based comparative teratology, this work evaluates the expression of Shh, Ptch-1, Gsc, and Msx2 in FON-exposed X. laevis embryos. Embryos, exposed to a high concentration level (500 µM) of FON from stage 13 till 17, were examined at stages 17, 27, and 47. Stage 17 and 27 embryos were processed to perform quantitative RT-PCR. The developmental rate was never affected by FON at any considered stage. FON-exposed stage 47 larvae showed the typical craniofacial malformations. A significant downregulation of Gsc was observed in FON-exposed stage 17 embryos. Shh, Ptch-1, Msx2 showed a high fluctuation of expression both in control and in FON-exposed samples both at stages 17 and 27. The downregulation of Gsc mimics the effects of FON on rat embryos, showing for this gene a common effect of FON in the two vertebrate classes. The high fluctuation observed in the gene expression of the other genes, however, suggests that X. laevis at this stage has limited utility for gene-based comparative teratology. © 2011 Wiley-Liss, Inc.

Activation of the CRABPII/RAR pathway by curcumin induces retinoic acid mediated apoptosis in retinoic acid resistant breast cancer cells

PubMed Central

Thulasiraman, Padmamalini; Garriga, Galen; Danthuluri, Veena; McAndrews, Daniel J.; Mohiuddin, Imran Q.

2017-01-01

Due to the anti-proliferative and anti-apoptotic effects of retinoic acid (RA), this hormone has emerged as a target for several diseases, including cancer. However, development of retinoid resistance is a critical issue and efforts to understand the retinoid signaling pathway may identify useful biomarkers for future clinical trials. Apoptotic responses of RA are exhibited through the cellular RA-binding protein II (CRABPII)/retinoic acid receptor (RAR) signaling cascade. Delivery of RA to RAR by CRABPII enhances the transcriptional activity of genes involved in cell death and cell cycle arrest. The purpose of this study was to investigate the role of curcumin in sensitizing RA-resistant triple-negative breast cancer (TNBC) cells to RA-mediated apoptosis. We provide evidence that curcumin upregulates the expression of CRABPII, RARβ and RARγ in two different TNBC cell lines. Co-treatment of the cells with curcumin and RA results in increased apoptosis as demonstrated by elevated cleavage of poly(ADP-ribose) polymerase and cleaved caspase-9. Additionally, silencing CRABPII reverses curcumin sensitization of TNBC cells to the apoptotic inducing effects of RA. These findings provide mechanistic insights into sensitizing TNBC cells to RA-mediated cell death by curcumin-induced upregulation of the CRABPII/RAR pathway. PMID:28350049

Retinoic acid catabolizing enzyme CYP26C1 is a genetic modifier in SHOX deficiency.

PubMed

Montalbano, Antonino; Juergensen, Lonny; Roeth, Ralph; Weiss, Birgit; Fukami, Maki; Fricke-Otto, Susanne; Binder, Gerhard; Ogata, Tsutomu; Decker, Eva; Nuernberg, Gudrun; Hassel, David; Rappold, Gudrun A

2016-12-01

Mutations in the homeobox gene SHOX cause SHOX deficiency, a condition with clinical manifestations ranging from short stature without dysmorphic signs to severe mesomelic skeletal dysplasia. In rare cases, individuals with SHOX deficiency are asymptomatic. To elucidate the factors that modify disease severity/penetrance, we studied a three-generation family with SHOX deficiency. The variant p.Phe508Cys of the retinoic acid catabolizing enzyme CYP26C1 co-segregated with the SHOX variant p.Val161Ala in the affected individuals, while the SHOX mutant alone was present in asymptomatic individuals. Two further cases with SHOX deficiency and damaging CYP26C1 variants were identified in a cohort of 68 individuals with LWD The identified CYP26C1 variants affected its catabolic activity, leading to an increased level of retinoic acid. High levels of retinoic acid significantly decrease SHOX expression in human primary chondrocytes and zebrafish embryos. Individual morpholino knockdown of either gene shortens the pectoral fins, whereas depletion of both genes leads to a more severe phenotype. Together, our findings describe CYP26C1 as the first genetic modifier for SHOX deficiency. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

Biphasic effect of citral, a flavoring and scenting agent, on spatial learning and memory in rats.

PubMed

Yang, Zheqiong; Xi, Jinlei; Li, Jihong; Qu, Wen

2009-10-01

Although some central effects of citral have been reported, cognitive effects on spatial memory have not been investigated. The evidence showed that citral can regulate the synthesis of retinoic acid (RA), which exerts a vital function in the development and maintenance of spatial memory. In this study, we applied Morris water maze to test the effect of citral on animals' spatial learning and memory. To elucidate the mechanism of this effect, we also measured the retinoic acid concentration in rats' hippocampus by high performance liquid chromatography (HPLC). Our data implied biphasic effects of citral. The low dose (0.1 mg/kg) of citral improved the spatial learning capability, and enhanced the spatial reference memory of rats, whereas the high dose (1.0 mg/kg) was like to produce the opposite effects. Meanwhile, the low dose of citral increased the hippocampal retinoic acid concentration, while the high dose decreased it. Due to the quick elimination and non-bioaccumulation in the body, effects of citral on spatial memory in this study seemed to be indirect actions. The change in hippocampal retinoic acid concentration induced by different doses of citral might be responsible for the biphasic effect of citral on spatial learning and memory.

Isotretinoin kinetics after 80 to 320 mg oral doses.

PubMed

Colburn, W A; Gibson, D M

1985-04-01

Twelve healthy male subjects received 80, 160, 240, and 320 mg doses of oral isotretinoin as multiples of 40 mg capsules separated by 2-week washout periods in a randomized, crossover design. Blood samples were drawn at specific times over a 72-hour period after dosing. Blood concentrations of isotretinoin as well as its major metabolite, 4-oxo-isotretinoin, were determined by a specific HPLC method. In addition to the normal laboratory battery of tests, serum triglyceride levels were determined before the first dose and again 72 hours after each of the four doses. Mean (+/- SD) maximum concentrations after 80 to 320 mg doses were 366 +/- 159, 820 +/- 474, 1056 +/- 547, and 981 +/- 381 ng/ml, whereas the respective AUC0-infinity values were 3690 +/- 1280, 7030 +/- 4140, 9780 +/- 6080, and 9040 +/- 2900 ng X hr/ml. The observed apparent elimination t1/2 remained approximately the same (14.7 hours) for each dose. The maximum concentration and AUC values for isotretinoin appear to be dose proportional from 80 to 240 mg but plateau at the 320 mg dose level. Therefore, because isotretinoin blood concentrations may not increase with higher doses in the fasting state, single, oral doses in excess of 240 mg should be used with caution. The data also suggest that elevated triglyceride levels are not a simple function of isotretinoin blood concentrations across the entire study population and dose range studied, but that in subjects with triglyceride levels in excess of the normal range triglyceride levels were positively related to isotretinoin blood concentrations.

Use of isotretinoin (Accutane) in the United States: rapid increase from 1992 through 2000.

PubMed

Wysowski, Diane K; Swann, Joslyn; Vega, Amarilys

2002-04-01

Isotretinoin, a drug approved to treat severe recalcitrant nodular acne, has been marketed in the United States since 1982. The drug is an effective treatment for acne that is refractory to other therapies, but it is a teratogen and can cause serious side effects. Our purpose was to describe trends in the use of isotretinoin in the United States from marketing through year 2000 and summarize characteristics of patients and prescribers. Data from 2 pharmaceutical marketing research databases, the National Prescription Audit Plus and the National Disease and Therapeutic Index, and from 2 health plan networks were obtained and analyzed. Retail pharmacies dispensed 19.8 million outpatient prescriptions for isotretinoin from marketing in 1982 through 2000. From 1983 through 1993, the median annual number of prescriptions was just over 800,000; between 1992 and 2000, the number of prescriptions increased 2.5-fold (250%) to nearly 2 million in year 2000. The increases registered in the health plans were somewhat larger: about 275% increases from 1995 through 1999. There is no ICD-9 code for nodulocystic acne; consequently, the type of acne treated with isotretinoin is not determinable from these data. However, between 1993 and 2000, the proportion of isotretinoin treatment for severe acne declined from 63% to 46%, whereas the proportion of treatment for mild and moderate acne increased from 31% to 49%. Data also indicated that the sex distribution of patients was nearly even, and that 63% of male patients prescribed isotretinoin were 15 to 19 years old, whereas 51% of female patients were 15 to 24 years old. In the last 8 years, there has been a 2.5-fold (250%) increase in the number of dispensed prescriptions for isotretinoin in the United States. Data also reveal an increasing proportion of isotretinoin use for mild and moderate acne.

Regulation of Epidermal Growth Factor Receptor Expression by PML in Human Breast Cancer.

DTIC Science & Technology

1996-08-01

Characterization of a zinc finger gene disrupted by the t(15; 17) in acute promyelocytic leukemia. Science, 254:1371-1374. (32) Fagioli , M., Alcalay, M...DISTRIBUTION CODE Approved for public release; distribution unlimited 13. ABSTRACT (Maximum 200 We have determined that PML is a novel growth suppressor that...was found to be translocated from chromosome 15 and fused with the retinoic acid receptor- a gene on chromosome 17 (t(15; 17) in acute promyelogenous

Linking autotrophic activity in environmental samples with specific bacterial taxa by detection of 13C-labelled fatty acids.

PubMed

Knief, Claudia; Altendorf, Karlheinz; Lipski, André

2003-11-01

A method for the detection of physiologically active autotrophic bacteria in complex microbial communities was developed based on labelling with the stable isotope 13C. Labelling of autotrophic nitrifying, sulphur-oxidizing and iron-oxidizing populations was performed in situ by incubation with NaH[13C]O3. Incorporated label into fatty acid methyl esters (FAMEs) was detected and quantified using gas chromatography-mass spectrometry in single ion monitoring mode. Before the analyses of different environmental samples, the protocol was evaluated in pure culture experiments. In different environmental samples a selective labelling of fatty acids demonstrated which microbial taxa were responsible for the respective chemolithoautotrophic activity. The most strongly labelled fatty acids of a sample from a sulphide treating biofilter from an animal rendering plant were cis-7-hexadecenoic acid (16:1 cis7) and 11-methyl hexadecanoic acid (16:0 11methyl), which are as-yet not known for any sulphide-oxidizing autotroph. The fatty acid labelling pattern of an experimental biotrickling filter sample supplied with dimethyl disulphide clearly indicated the presence and activity of sulphide-oxidizing bacteria of the genus Thiobacillus. For a third environmental sample from an acid mining lake sediment, the assignment of autotrophic activity to bacteria of the genus Leptospirillum but not to Acidithiobacillus could be made by this method, as the fatty acid patterns of these bacteria show clear differences.

Comparative Effects of Retinoic Acid or Glycolic Acid Vehiculated in Different Topical Formulations

PubMed Central

Maia Campos, Patrícia Maria Berardo Gonçalves; Gaspar, Lorena Rigo; Gonçalves, Gisele Mara Silva; Pereira, Lúcia Helena Terenciane Rodrigues; Semprini, Marisa; Lopes, Ruberval Armando

2015-01-01

Retinoids and hydroxy acids have been widely used due to their effects in the regulation of growth and in the differentiation of epithelial cells. However, besides their similar indication, they have different mechanisms of action and thus they may have different effects on the skin; in addition, since the topical formulation efficiency depends on vehicle characteristics, the ingredients of the formulation could alter their effects. Thus the objective of this study was to compare the effects of retinoic acid (RA) and glycolic acid (GA) treatment on the hairless mouse epidermis thickness and horny layer renewal when added in gel, gel cream, or cream formulations. For this, gel, gel cream, and cream formulations (with or without 6% GA or 0.05% RA) were applied in the dorsum of hairless mice, once a day for seven days. After that, the skin was analyzed by histopathologic, morphometric, and stereologic techniques. It was observed that the effects of RA occurred independently from the vehicle, while GA had better results when added in the gel cream and cream. Retinoic acid was more effective when compared to glycolic acid, mainly in the cell renewal and the exfoliation process because it decreased the horny layer thickness. PMID:25632398

Critical determinant of intestinal permeability and oral bioavailability of pegylated all trans-retinoic acid prodrug-based nanomicelles: Chain length of poly (ethylene glycol) corona.

PubMed

Li, Zhenbao; Han, Xiaopeng; Zhai, Yinglei; Lian, He; Zhang, Dong; Zhang, Wenjuan; Wang, Yongjun; He, Zhonggui; Liu, Zheng; Sun, Jin

2015-06-01

Pegylation method is widely used to prolong the blood circulation time of proteins and nanoparticles after intravenous administration, but the effect of surface poly (ethylene glycol) (PEG) chain length on oral absorption of the pegylated nanoparticles is poorly reported. The aim of our study was to investigate the influence of PEG corona chain length on membrane permeability and oral bioavailability of the amphiphilic pegylated prodrug-based nanomicelles, taking all trans-retinoic acid (ATRA) as a model drug. The amphiphilic ATRA-PEG conjugates were synthesized by esterification reaction between all trans-retinoic acid and mPEGs (mPEG500, mPEG1000, mPEG2000, and mPEG5000). The conjugates could self-assemble in aqueous medium to form nanomicelles by emulsion-solvent evaporation method. The resultant nanomicelles were in spherical shape with an average diameter of 13-20 nm. The drug loading efficiency of ATRA-PEG500, ATRA-PEG1000, ATRA-PEG2000, and ATRA-PEG5000 was about 38.4, 26.6, 13.1, and 5.68 wt%, respectively. With PEG chain length ranging from 500 to 5000, ATRA-PEG nanomicelles exhibited a bell shape of chemical stability in different pH buffers, intestinal homogenate and plasma. More importantly, they were all rapidly hydrolyzed into the parent drug in hepatic homogenate, with the half-time values being 0.3-0.4h. In comparison to ATRA solution and ATRA prodrug-based nanomicelles, ATRA-PEG1000 showed the highest intestinal permeability. After oral administration, ATRA-PEG2000 and ATRA-PEG5000 nanomicelles were not nearly absorbed, while the oral bioavailability of ATRA-PEG500 and ATRA-PEG1000 demonstrated about 1.2- and 2.0-fold higher than ATRA solution. Our results indicated that PEG1000 chain length of ATRA-PEG prodrug nanomicelles has the optimal oral bioavailability probably due to improved stability and balanced mucus penetration capability and cell binding, and that the PEG chain length on a surface of nanoparticles cannot exceed a key threshold with the purpose of enhancement in oral bioavailability. Copyright © 2015. Published by Elsevier B.V.

Pokemon decreases the transcriptional activity of RARα in the absence of ligand.

PubMed

Yang, Yutao; Li, Yueting; Di, Fei; Cui, Jiajun; Wang, Yue; David Xu, Zhi-Qing

2016-12-20

Pokemon is a transcriptional repressor that belongs to the POZ and Krüppel (POK) protein family. In this study, we investigated the potential interaction between Pokemon and retinoic acid receptor alpha (RARα) and determined the role of Pokemon in regulation of RARα transcriptional activity in the absence of ligand. We found that Pokemon could directly interact with RARα. Moreover, we demonstrated that Pokemon could decrease the transcriptional activity of RARα in the absence of ligand. Furthermore, we showed that Pokemon could repress the transcriptional activity of RARα by increasing the recruitment of nuclear receptor co-repressor (NCoR) and silencing mediator of retinoic acid and thyroid hormone receptor (SMRT) to the retinoic acid response element (RARE) element. Taken together, these data suggest that Pokemon is a novel partner of RARα that acts as a co-repressor to regulate RARα transcriptional activity in the absence of ligand.

Retinoic acid-induced lumbosacral neural tube defects: myeloschisis and hamartoma.

PubMed

Cai, WeiSong; Zhao, HongYu; Guo, JunBin; Li, Yong; Yuan, ZhengWei; Wang, WeiLin

2007-05-01

To observe the morphological features of the lumbosacral neural tube defects (NTDs) induced by all-trans retinoic acid (atRA) and to explore the pathogenesis of these defects. Rat embryos with lumbosacral NTDs were obtained by treating pregnant rats with administration of atRA. Rat embryos were obtained by cesarean. Fetuses were sectioned and stained with hematoxylin-eosin (H&E). Relevant structures including caudal neural tube were examined. In the atRA-treated rats, about 48% embryos showed lumbosacral NTDs. There appeared a dorsally and rostrally situated, neural-plate-like structure (myeloschisis) and a ventrally and caudally located cell mass containing multiple canals (hamartoma) in the lumbosacral NTDs induced by atRA. Retinoic acid could disturb the notochord and tail bud development in the process of primary and secondary neurulation in rat embryos, which cause lumbosacral NTDs including myeloschisis and hamartoma. The morphology is very similar to that happens in humans.

Retinoic acid signaling in cancer: The parable of acute promyelocytic leukemia.

PubMed

Ablain, Julien; de Thé, Hugues

2014-11-15

Inevitably fatal some 40 years, acute promyelocytic leukemia (APL) can now be cured in more than 95% of cases. This clinical success story is tightly linked to tremendous progress in our understanding of retinoic acid (RA) signaling. The discovery of retinoic acid receptor alpha (RARA) was followed by the cloning of the chromosomal translocations driving APL, all of which involve RARA. Since then, new findings on the biology of nuclear receptors have progressively enlightened the basis for the clinical efficacy of RA in APL. Reciprocally, the disease offered a range of angles to approach the cellular and molecular mechanisms of RA action. This virtuous circle contributed to make APL one of the best-understood cancers from both clinical and biological standpoints. Yet, some important questions remain unanswered including how lessons learnt from RA-triggered APL cure can help design new therapies for other malignancies. © 2014 UICC.

Molecular cloning and expression profile of ß-ketoacyl-acp synthase gene from tung tree (Vernicia fordii Hemsl.)

USDA-ARS?s Scientific Manuscript database

Tung tree (Vernicia fordii) is an important woody oil tree. Tung tree seeds contain 50-60% oil with approximately 80 mole a-eleostearic acid (9cis, 11trans, 13trans octadecatrienoic acid). Fatty acid synthesis is catalyzed by the concerted action of acetyl-CoA carboxylase and fatty acid synthase, a ...

Isotretinoin and mental health in adolescents: Australian consensus.

PubMed

Rowe, Casey; Spelman, Lynda; Oziemski, Margaret; Ryan, Alexander; Manoharan, Shobhan; Wilson, Perry; Daubney, Michael; Scott, James

2014-05-01

Acne is a common condition among adolescents and has the potential to negatively impact on the psychological well-being of those who suffer from it. In particular, depression and suicidal ideation are more common in adolescents with acne. Successful treatment of acne can improve the quality of life and reduce levels of anxiety and depression in these individuals. The current treatment of choice for severe or refractive acne is isotretinoin, a retinoid. While the possible causal association between isotretinoin and mental illness remains a controversial topic, a recent systematic review has presented evidence to support this relationship. In light of this evidence, a group of dermatologists and psychiatrists have collaborated to develop these recommendations to aid the safe prescribing of isotretinoin in adolescents. These clinical suggestions are aimed at practitioners in both disciplines to increase awareness of the current evidence in support of the association between isotretinoin and adolescent depression. © 2013 The Australasian College of Dermatologists.

Isotretinoin therapy for acne: a population-based study.

PubMed Central

Hogan, D J; Strand, L M; Lane, P R

1988-01-01

The use of isotretinoin over a 2-year period was retrospectively studied in Saskatchewan. The database of the Saskatchewan Prescription Drug Plan was used to obtain the names of physicians who prescribed isotretinoin as well as the names of patients for whom it was prescribed. Of the 861 such patients 161 had been instructed to use the drug for at least 4 months by 42 physicians. Questionnaires were returned by 86 of the 161 patients and 22 of the 42 physicians. The responses confirmed that isotretinoin therapy is highly effective for acne. However, at least half of the patients for whom the agent was prescribed apparently did not complete a full 4- to 5-month course of treatment, and of the 34 women (average age 28 years) who responded to the questionnaire 12 (35%) did not use a method of contraception, which is a matter of concern in view of isotretinoin's teratogenic effects. PMID:2961430

Four new triterpenoids from the leaves of Psidium guajava.

PubMed

Shao, Meng; Wang, Ying; Huang, Xiao-Jun; Fan, Chun-Lin; Zhang, Qing-Wen; Zhang, Xiao-Qi; Ye, Wen-Cai

2012-01-01

Four new triterpenoids, psiguanins A-D (1-4), along with 13 known ones (5-17), were isolated from the leaves of Psidium guajava. The structures of new compounds were determined as 2α,3β-dihydroxy-taraxer-20-en-28-oic acid (1), 2α,3β,12α,13β-tetrahydroxy-urs-28-oic acid (2), 2α,3β,12β,13β-tetrahydroxy-urs-28-oic acid (3), and 2α,3β,12β,13α-tetrahydroxy-urs-28-oic acid (4), respectively, on the basis of comprehensive spectroscopic methods and molecular modeling calculation. Among them, compound 4 was characterized as an unusual ursane-type triterpenoid with cis-fused C/D ring system.

Comparison of the ligand binding properties of two homologous rat apocellular retinol-binding proteins expressed in Escherichia coli.

PubMed

Levin, M S; Locke, B; Yang, N C; Li, E; Gordon, J I

1988-11-25

Cellular retinol-binding protein (CRBP) and cellular retinol-binding protein II (CRBP II) are 132-residue cytosolic proteins which have 56% amino acid sequence identity and bind all-trans-retinol as their endogenous ligand. They belong to a family of cytoplasmic proteins which have evolved to bind distinct hydrophobic ligands. Their patterns of tissue-specific and developmental regulation are distinct. We have compared the ligand binding properties of rat apo-CRBP and apo-CRBP II that have been expressed in Escherichia coli. Several observations indicate that the E. coli-derived apoproteins are structurally similar to the native rat proteins: they co-migrate on isoelectric focusing gels; and when complexed with all-trans-retinol, their absorption and excitation/emission spectra are nearly identical to those of the authentic rat holoproteins. Comparative lifetime and acrylamide quenching studies suggest that there are differences in the conformations of apo-CRBP and apo-CRBP II. The interaction of E. coli-derived apo-CRBP and apo-CRBP II with a variety of retinoids was analyzed using spectroscopic techniques. Both apoproteins formed high affinity complexes with all-trans-retinol (K'd approximately 10 nM). In direct binding assays, all-trans-retinal bound to both apoproteins (K'd approximately 50 nM for CRBP; K'd approximately 90 nM for CRBP II). However, all-trans-retinal could displace all-trans-retinol bound to CRBP II but not to CRBP. These observations suggests that there is a specific yet distinct interaction between these two proteins and all-trans-retinal. Apo-CRBP and apo-CRBP II did not demonstrate significant binding to either retinoic acid or methyl retinoate, an uncharged derivative of all-trans-retinoic acid. This indicates that the carboxymethyl group of methyl retinoate cannot be sterically accommodated in their binding pockets and that failure to bind retinoic acid probably is not simply due to the negative charge of its C-15 carboxylate group. Finally, neither all-trans-retinol nor retinoic acid bound to E. coli-derived rat intestinal fatty acid-binding protein, a homologous protein whose tertiary structure is known. Together, the data suggest that these three family members have acquired unique functional capabilities.

[Clinical and monitoring experience of isotretinoin in Italy].

PubMed

Cavicchini, S; Bottoni, A; Caputo, R

1989-01-01

We report the results of a multicentric evaluation on effectiveness and safety of isotretinoin in severe acne, recalcitrant to traditional treatments. 208 patients, suffering especially from cystic acne, have been enrolled in a post-marketing clinical trial in 11 Dermatological Italian Departments. The clinical effectiveness of isotretinoin has been very good in 77% of patients, good in 16% and sufficient in 4%. The tolerability of the drug was considered good in 90% of patients. Finally, isotretinoin might be considered as one of the most effective drugs in the therapy of severe forms of acne, resistant to usual treatment, and often affecting patients on the physical and psychological side.

Isotretinoin, depression and suicide: a review of the evidence

PubMed Central

Magin, Parker; Pond, Dimity; Smith, Wayne

2005-01-01

There is currently considerable controversy regarding a proposed causal relationship between the use of isotretinoin and depression and suicide. A search was made of the MEDLINE, EMBASE and PsychINFO databases using the search terms ‘isotretinoin’, ‘depression’ and ‘suicide’. Despite numerous case reports linking isotretinoin to depression, suicidal ideation and suicide, there is, as yet, no clear proof of an association. While isotretinoin, used to treat acne vulgaris, has not been demonstrated to be associated with depression or suicide, the possibility of a relatively rare idiosyncratic adverse effect remains. GPs have a role in the clinical application of these findings. PMID:15720936

Psychiatric disorders, acne and systemic retinoids: comparison of risks.

PubMed

Le Moigne, M; Bulteau, S; Grall-Bronnec, Marie; Gerardin, M; Fournier, Jean-Pascal; Jonville-Bera, A P; Jolliet, Pascale; Dreno, Brigitte; Victorri-Vigneau, C

2017-09-01

The link between isotretinoin, treatment of a severe form of acne, and psychiatric disorders remains controversial, as acne itself could explain the occurrence of psychiatric disorders. This study aims at assessing the disproportionality of psychiatric adverse events reported with isotretinoin in the French National PharmacoVigilance Database, compared with other systemic acne treatments and systemic retinoids. Data were extracted from the French National PharmacoVigilance Database for systemic acne treatments, systemic retinoids and drugs used as comparators. Each report was subjected to double-blind analysis by two psychiatric experts. A disproportionality analysis was performed, calculating the number of psychiatric ADRs divided by the total number of notifications for each drug of interest. Concerning acne systemic treatments: all 71 reports of severe psychiatric disorders involved isotretinoin, the highest proportion of mild/moderate psychiatric adverse events was reported with isotretinoin (14.1%). Among systemic retinoids, the highest proportion of severe and mild/moderate psychiatric events occurred with isotretinoin and alitretinoin. Our study raises the hypothesis that psychiatric disorders associated with isotretinoin are related to a class effect of retinoids, as a signal emerges for alitretinoin. Complementary studies are necessary to estimate the risk and further determine at-risk populations.

A comparison of the efficacy of topical tretinoin and low-dose oral isotretinoin in rosacea.

PubMed

Ertl, G A; Levine, N; Kligman, A M

1994-03-01

Twenty-two patients with severe or recalcitrant rosacea were divided into three treatment groups in a randomized, double-blind trial that compared low-dose oral isotretinoin (10 mg/d), topically applied tretinoin (0.025% cream), and the combined use of both isotretinoin and tretinoin. For the first 16 weeks of the trial, subjects received one of these three trial regimens. For the final 16 weeks, isotretinoin was withheld while tretinoin cream or a placebo cream was continued. Twenty subjects completed the trial. Each treatment produced therapeutic benefits with regard to the number of papules and pustules and erythema. Treatment with oral isotretinoin appeared to give a more rapid onset of improvement, but there were no differences between the groups after 16 weeks. This level of improvement continued during the succeeding 16 weeks of observation whether the subjects used the tretinoin or the placebo cream. Adverse events were minimal and well tolerated in all groups. Low-dose oral isotretinoin and topical tretinoin cream therapy appear to be beneficial in the treatment of severe or recalcitrant rosacea. No additive benefit is noted with the combined use of these two modalities.

Successful treatment of palmoplantar pustulosis with isotretinoin.

PubMed

Wilken, Reason; Sharma, Ajay; Patel, Forum; Maverakis, Emanual

2015-08-15

Variably considered as a localized subtype of pustular psoriasis, palmoplantar pustulosis (PPP) is commonly treated with topical steroids, acitretin, and local phototherapy with oral or topical psoralen (PUVA). The utility of acitretin for PPP is limited by adverse effects such as myalgias and an extended risk of teratogenicity in female patients. Isotretinoin is a more tolerable retinoid with a shorter teratogenic window, but to date its effectiveness in PPP has not been reported. Herein we present two patients with PPP who responded well to isotretinoin treatment. Two patients with PPP refractory to topical therapies were started on acitretin. Both patients developed adverse effects (including headache, myalgias, and mood alterations) leading to acitretin discontinuation. Isotretinoin monotherapy was started in one patient resulting in significant clearing of palmar plaques and scale, and the addition of isotretinoin to UVA therapy resulted in near-complete clearing of recalcitrant plantar plaques in the second patient. Acitretin represents an important treatment for PPP, but is limited by adverse effects and extended teratogenicity. Our experience supports the utility of isotretinoin as a potential therapeutic alternative, which may be particularly beneficial in patients who are poor candidates for or unable to tolerate acitretin therapy.

Effect of retinoic acid on midkine gene expression in rat anterior pituitary cells.

PubMed

Maliza, Rita; Fujiwara, Ken; Azuma, Morio; Kikuchi, Motoshi; Yashiro, Takashi

2017-06-29

Retinoic acid (RA) is converted from retinal by retinaldehyde dehydrogenases (RALDHs) and is an essential signaling molecule in embryonic and adult tissue. We previously reported that RALDH1 was produced in the rat anterior pituitary gland and hypothesized that RA was generated in the gland. Midkine (MK) is an RA-inducible growth factor, and MK production in the rat anterior pituitary gland was recently reported. However, the mechanism that regulates gene expression of MK in the pituitary gland has not been determined. To investigate regulation of MK production in the anterior pituitary gland, we analyzed changes in MK mRNA in cultured rat anterior pituitary cells. We identified MK-expressing cells by double-staining with in situ hybridization and immunohistochemical techniques for RALDH1. MK mRNA was expressed in RALDH1-producing cells in the anterior pituitary gland. Using isolated anterior pituitary cells of rats, we examined the effect of RA on gene expression of MK. Quantitative real-time PCR revealed that 72 h exposure to a concentration of 10 -6 M of retinal and all-trans retinoic acid increased MK mRNA levels by about 2-fold. Moreover, the stimulatory effect of all-trans retinoic acid was mimicked by the RA receptor agonist Am80. This is the first report to show that RA is important in regulating MK expression in rat anterior pituitary gland.

Thermometric sensing of peroxide in organic media. Application to monitor the stability of RBP-retinol-HRP complex.

PubMed

Ramanathan, K; Jönsson, B R; Danielsson, B

2000-08-01

The stability of horseradish peroxidase (HRP) in aqueous and organic solvents is applied to develop a simple thermometric procedure to detect the binding of retinoic acid-HRP conjugate to retinol binding protein (RBP). Butanone peroxide (BP) in organic phase and hydrogen peroxide in aqueous phase is detected thermometrically on a HRP column, immobilized by cross-linking with glutaraldehyde on controlled pore glass (CPG). Acetone, acetonitrile, methanol, and 2-butanol are used for detection of BP, in the flow injection analysis (FIA) mode. A linear range between 1 and 50 mM BP is obtained in all the organic solvents with a precision of 5-7% (CV%). The magnitude and nature of the thermometric response is significantly different in each organic solvent. The stability of HRP in the organic phase is used to study the stability of a retinoic acid-HRP conjugate bound to immobilized RBP. The response of HRP (to 20 mM BP) in the retinoic acid-HRP conjugate is used as an indicator of the stability of the RBP-retinoic acid-HRP complex, after challenges with various organic/aqueous solvents. Both immobilized HRP and RBP are stable at least for 6 months. The effect of o-phenylene diamine on the thermometric response of HRP is also investigated. A scheme for the design of a thermometric retinol (vitamin A) biosensor is proposed.

Piwil1 mediates meiosis during spermatogenesis in chicken.

PubMed

Xu, Lu; Chang, Guobin; Ma, Teng; Wang, Hongzhi; Chen, Jing; Li, Zhiteng; Guo, Xiaomin; Wan, Fang; Ren, Lichen; Lu, Wei; Chen, Guohong

2016-03-01

Piwil1 mediates spermatogenesis and ensures stable cell division rates in germline cells in mammals. However, the involvement of Piwil1 in poultry spermatogenesis and meiosis is poorly understood. In the present study, we used TaqMan RT-qPCR to characterize Piwil1 mRNA expression in different types of spermatogenic cells, including primordial germ cells (PGCs), spermatogonial stem cells (SSCs), spermatogonia cells (Sa), tetraploid cells (Tp), round sperm cells (Rs), mature sperm, and in PGCs treated with retinoic acid. Our results revealed that Piwil1 is differentially expressed during spermatogenesis in chicken. Compared to PGCs, SSCs, Tp, and Sa, Rs cells presented the highest Piwil1 mRNA expression levels. Retinoic acid significantly upregulated Piwil1 and Stra8 mRNA expression as well as Piwil1 levels in chicken PGCs. In addition, retinoic acid induced PGCs to progress through all the meiotic stages, eventually leading to haploid cell formation, which was determined using flow cytometry and western blot analysis. Taken together, our results showed that during spermatogenesis, Piwil1 was first expressed at low levels in germ stem cells, PGCs, and SSCs. Its expression levels increased during later meiosis stages. Finally, no expression was detected in mature sperm after meiosis. Treatment of PGCs with retinoic acid further demonstrated that Piwil1 plays a key role in meiosis during chicken spermatogenesis. Copyright © 2016 Elsevier B.V. All rights reserved.

Retinoic acids and trichostatin A (TSA), a histone deacetylase inhibitor, induce human pyruvate dehydrogenase kinase 4 (PDK4) gene expression.

PubMed

Kwon, Hye-Sook; Huang, Boli; Ho Jeoung, Nam; Wu, Pengfei; Steussy, Calvin N; Harris, Robert A

2006-01-01

Induction of pyruvate dehydrogenase kinase 4 (PDK4) conserves glucose and substrates for gluconeogenesis and thereby helps regulate blood glucose levels during starvation. We report here that retinoic acids (RA) as well as Trichostatin A (TSA), an inhibitor of histone deacetylase (HDAC), regulate PDK4 gene expression. Two retinoic acid response elements (RAREs) to which retinoid X receptor alpha (RXRalpha) and retinoic acid receptor alpha (RARalpha) bind and activate transcription are present in the human PDK4 (hPDK4) proximal promoter. Sp1 and CCAAT box binding factor (CBF) bind to the region between two RAREs. Mutation of either the Sp1 or the CBF site significantly decreases basal expression, transactivation by RXRalpha/RARalpha/RA, and the ability of TSA to stimulate hPDK4 gene transcription. By the chromatin immunoprecipitation assay, RA and TSA increase acetylation of histones bound to the proximal promoter as well as occupancy of CBP and Sp1. Interaction of p300/CBP with E1A completely prevented hPDK4 gene activation by RXRalpha/RARalpha/RA and TSA. The p300/CBP may enhance acetylation of histones bound to the hPDK4 promoter and cooperate with Sp1 and CBF to stimulate transcription of the hPDK4 gene in response to RA and TSA.

Backbone resonance assignments of the PRYSPRY domain of TRIM25.

PubMed

Kong, Chen; Penumutchu, Srinivasa R; Hung, Kuo-Wei; Huang, Huiying; Lin, Tianwei; Yu, Chin

2015-10-01

TRIM25 is a member of the tripartite motif (TRIM) family and has been implicated in the regulation of innate immune signaling via the RIG-I (retinoic acid-inducible gene-I) pathway for antiviral defense. As the essential first step towards the structural and functional characterization of the TRIM25/RIG-I interaction, the backbone resonance of the PRYSPRY domain of TRIM25 is assigned here based on triple-resonance experiments using uniformly [(2)H, (13)C, (15)N]-labeled protein.

Vibrational spectroscopic study on polymorphism of erucic acid and palmitoleic acid: γ1→α1 and γ→α reversible solid state phase transitions

NASA Astrophysics Data System (ADS)

Kaneko, Fumitoshi; Yamazaki, Kazuhiro; Kobayashi, Masamichi; Sato, Kiyotaka; Suzuki, Masao

1994-08-01

The infrared and Raman spectra of four polymorphic phases (α, α1, γ and γ1) of erucic acid ( cis-13-docosenoic acid) and those of two polymorphic phases (α and γ) of palmitoleic acid ( cis-9-hexadecenoic acid) were investigated. The γ and γ1 phases of erucic acid were analyzed on the basis of crystal structures determined by us. There were large spectral differences between γ and γ1 phases, which could be ascribed to the differences in the conformation of cis-olefin groups and the subcell structure. Two types of reversible solid state phase transitions (γ→α and γ1→α1 transitions) were followed by the infrared and Raman spectra. It was concluded that the mechanism of the γ→α phase transition of erucic and palmitoleic acids is essentially the same as that of oleic acid previously reported by us [ J. Phys. Chem.90, 6371 (1986)], i.e. this phase transition is of order-disorder type accompanied by a conformational disordering at the methyl-terminal chain. Spectral changes on the γ1→α1 transition suggested that a similar structural change took place during this transition but there were large structural differences between α and α1.

Comparative proteomic expression profile in all-trans retinoic acid differentiated neuroblastoma cell line.

PubMed

Cimmino, Flora; Spano, Daniela; Capasso, Mario; Zambrano, Nicola; Russo, Roberta; Zollo, Massimo; Iolascon, Achille

2007-07-01

Neuroblastoma (NB) is an infant tumor which frequently differentiates into neurons. We used two-dimensional differential in-gel electrophoresis (2D-DIGE) to analyze the cytosolic and nuclear protein expression patterns of LAN-5 cells following neuronal differentiating agent all-trans-retinoic acid treatment. We identified several candidate proteins, from which G beta2 and Prefoldin 3 may have a role on NB development. These results strength the use of proteomics to discover new putative protein targets in cancer.

Expression and Regulation of the Retinoic Acid Receptor Beta Gene in Human Mammary Epithelial Cells

DTIC Science & Technology

1996-09-01

Balb/c nu/nu female mice. We have obtained experimental design advice from Dr. Janet Price, University of Texas, M.D. Anderson Cancer Center, Houston...author(s) and should not be construed as an official Department of the Army position, policy or decision unless so designated by other documentation...identified eight genes regulated by retinoic acid in either breast cancer cell lines and/or normal HMECs. We have continued to evaluate the methodology to

Retinoic acid-induced differentiation of retrovirus-infected HL-60 cells is associated with enhanced transcription from the viral long terminal repeat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collins, S.J.

1988-11-01

The author infected different human leukemic cell lines with an amphotropic retrovirus vector (designated PA317/N2) which confers G418 resistance and contains the Moloney murine leukemia virus long terminal repeat. In retrovirus-infected G418-resistant HL-60 cells, induction of granulocyte differentiation by retinoic acid was invariably accompanied by a marked increase (5- to 10-fold) in the transcriptional activity of the integrated retroviral long terminal repeat.

Isotretinoin-induced urethritis versus non-gonococcal urethritis in a man who has sex with men: an open debate.

PubMed

Ballout, Rami A; Maatouk, Ismael

2018-01-01

This is the case of a young man presenting with urethritis despite a negative infectious work-up. Careful history taking elucidated a strong correlation between symptom onset and a recent dose escalation of isotretinoin for treatment of his refractory cystic acne. The urethral symptoms quickly resolved with dose reduction, suggesting urethritis as a rare adverse reaction of isotretinoin.

Effect of route of administration and biliary excretion on the pharmacokinetics of isotretinoin in the dog.

PubMed

Cotler, S; Chen, S; Macasieb, T; Colburn, W A

1984-01-01

Oral, intraportal, iv doses of isotretinoin were administered to dogs before and after bile duct cannulation to determine the effect of route of administration and biliary excretion on the pharmacokinetics of this compound. Blood and bile samples were collected and analyzed for isotretinoin using a gradient elution high performance liquid chromatographic method. Blood concentrations were decreased after bile duct cannulation. Decreases in the area under the blood concentration-time curves were greatest following oral dosing, intermediate following intraportal dosing, and least following iv dosing. These results indicate that biliary excretion impacts on the blood profile of isotretinoin as a function of route of administration and that the differences are the result of differences in first pass clearance. In addition, the apparent bioavailability of isotretinoin was 14% in bile cannulated dogs and 54% in the intact (uncannulated) animals, suggesting that enterohepatic recycling of isotretinoin may contribute to its oral bioavailability. Isotretinoin was excreted in the bile; predominantly as a conjugate. The largest percentage (approximately 27%) of the dose was excreted in the bile following intraportal infusion, an intermediate percentage (approximately 8.5%) after iv dosing, and the smallest percentage (approximately 3.3%) after oral dosing. When the amount of drug excreted in bile as intact drug and conjugate is divided by the area under the systemic blood concentration--time curve, the resulting apparent biliary clearances following oral and intraportal administration were almost identical whereas the apparent biliary clearance after iv dosing was substantially less.(ABSTRACT TRUNCATED AT 250 WORDS)

The prevalence of sacroiliitis in patients with acne vulgaris using isotretinoin.

PubMed

Baykal Selçuk, Leyla; Aksu Arıca, Deniz; Baykal Şahin, Hanife; Yaylı, Savas; Bahadır, Sevgi

2017-06-01

Acne vulgaris is a chronic inflammatory disease affecting the pilosebaceous unit in the skin. Isotretinoin is a synthetic vitamin A derivative regarded as the most effective agent in the treatment of acne. There have recently been increasing reports of adverse effects of isotretinoin on the skeletal system. Our aim in this study was to evaluate the rheumatic side-effects triggered by this drug, and particularly the prevalence of sacroiliitis. A total of 73 patients receiving isotretinoin due to moderate or severe acne vulgaris were included. All patients were questioned about inflammatory low back pain and musculoskeletal pains during the treatment process. Inflammatory low back pain was evaluated using Assessment of Spondyloarthritis International Society (ASAS) criteria. Patients meeting ASAS criteria were evaluated with radiography and when necessary with sacroiliac magnetic resonance. The dose range for isotretinoin was between 0.4 and 0.8 mg/kg/day (mean 0.53 mg/kg/day). Treatment lasted for 6-8 months (mean 6.8 months). Lethargy was determined in 37 (50.7%) patients, myalgia in 31 (42.5%) and low back pain in 36 (49.3%). Mechanical low back pain symptoms were present in 20 of the patients describing low back pain and inflammatory low back pain in 16. Acute sacroiliitis was determined in six patients (8.2%) following a sacroiliac magnetic resonance imaging (MRI). Five (83.3%) of the patients with sacroiliitis were female and one (16.7%) was male. No statistically significant difference was determined between male and female patients in terms of prevalence of sacroiliitis (p = 0.392). The incidence of sacroiliitis in patients using isotretinoin is quite high. Patients using isotretinoin must be questioned about sacroiliitis findings and must be subjected to advanced assessment when necessary. Further studies regarding the development of sacroiliitis under isotretinoin therapy are now needed.

Comparative genomic and phylogenetic analysis of short-chain dehydrogenases/reductases with dual retinol/sterol substrate specificity.

PubMed

Belyaeva, Olga V; Kedishvili, Natalia Y

2006-12-01

Human short-chain dehydrogenases/reductases with dual retinol/sterol substrate specificity (RODH-like enzymes) are thought to contribute to the oxidation of retinol for retinoic acid biosynthesis and to the metabolism of androgenic and neuroactive 3alpha-hydroxysteroids. Here, we investigated the phylogeny and orthology of these proteins to understand better their origins and physiological roles. Phylogenetic and genomic analysis showed that two proteins (11-cis-RDH and RDHL) are highly conserved, and their orthologs can be identified in the lower taxa, such as amphibians and fish. Two other proteins (RODH-4 and 3alpha-HSD) are significantly less conserved. Orthologs for 3alpha-HSD are present in all mammals analyzed, whereas orthologs for RODH-4 can be identified in some mammalian species but not in others due to species-specific gene duplications. Understanding the evolution and divergence of RODH-like enzymes in various vertebrate species should facilitate further investigation of their in vivo functions using animal models.

40 CFR 180.636 - 1,3-dichloropropene; tolerances for residues.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Specific Tolerances...-chloroacrylic acid, and cis- and trans-3-chloroallyl alcohol in or on the following commodities. Commodity Parts...

Effect of ellagic acid on proliferation, cell adhesion and apoptosis in SH-SY5Y human neuroblastoma cells.

PubMed

Fjaeraa, Christina; Nånberg, Eewa

2009-05-01

Ellagic acid, a polyphenolic compound found in berries, fruits and nuts, has been shown to possess growth-inhibiting and apoptosis promoting activities in cancer cell lines in vitro. The objective of this study was to investigate the effect of ellagic acid in human neuroblastoma SH-SY5Y cells. In cultures of SH-SY5Y cells incubated with ellagic acid, time- and concentration-dependent inhibitory effects on cell number were demonstrated. Ellagic acid induced cell detachment, decreased cell viability and induced apoptosis as measured by DNA strand breaks. Ellagic acid-induced alterations in cell cycle were also observed. Simultaneous treatment with all-trans retinoic acid did not rescue the cells from ellagic acid effects. Furthermore, the results suggested that pre-treatment with all-trans retinoic acid to induce differentiation and cell cycle arrest did not rescue the cells from ellagic acid-induced cell death.

New ester alkaloids from lupins (genus lupinus).

PubMed

Mühlbauer, P; Witte, L; Wink, M

1988-06-01

Esters of 13-hydroxylupanine and 4-hydroxylupanine with acetic, propionic, butyric, isobutyric, valeric, isovaleric, tiglic, benzoic, and TRANS-cinnamic acid have been synthesized and characterized by capillary gas-liquid chromatography and mass spectrometry (EI-MS, CI-MS). In LUPINUS POLYPHYLLUS, L. ALBUS, L. ANGUSTIFOLIUS, and L. MUTABILIS we could identify new ester alkaloids (e.g. 13-propyloxylupanine, 13-butyryloxylupanine, 13-isobutyryloxylupanine, and 4-tigloyloxylupanine) besides the known esters, i.e. 13-acetoxylupanine, 13-isovaleroyloxylupanine, 13-angeloyloxylupanine, 13-tigloyloxylupanine, 13-benzoyloxylupanine, 13- CIS-cinnamoyloxylupanine nine, and 13- TRANS-cinnamoyloxylupanine.

Psychological impact of isotretinoin treatment in patients with moderate and severe acne.

PubMed

Simić, Dubravka; Situm, Mirna; Letica, Edita; Penavić, Jasna Zeljko; Zivković, Maja Vurnek; Tomić, Teo

2009-12-01

Acne patients are subject to different degree of psychosocial distress. The emotional impact of acne vulgaris due to disfigurement caused by the disease is undisputed. Most common reactions to the acne are depression and anxiety. The use of isotretinoin, one of the most effective options in acne treatment, increases depression symptoms. The aim of this study was to investigate the psychological status of the patients with moderate to severe acne and to compare patients treated with isotretinoin with patients treated with vitamin C. A total of 85 patients suffering from acne vulgaris were included in the study. The results of this study do not find a significant correlation between the use of isotretinoin and the psychological effects of the drug.

Obsessive-compulsive disorder with bipolar diathesis following isotretinoin therapy remitting upon treatment with olanzapine and fluvoxamine

PubMed Central

Fornaro, Michele

2010-01-01

Isotretinoin, a drug used for moderate to severe acne, has been repeatedly associated with various psychiatric complications, although a definitive causal relationship has not been established to date. This case report describes a 25-year-old male who developed obsessive-compulsive disorder at the age of 23 years following isotretinoin treatment for acne (10–20 mg/day) since the age of 16 years. Although standard treatment for obsessive-compulsive disorder caused mood swings, the combination of fluvoxamine 300 mg/day and olanzapine 15 mg/day significantly improves the clinical picture. Although rare, severe adulthood psychiatric complications may occur following isotretinoin treatment, requiring management which is individually tailored to the patient. PMID:21127690

Utilization of DR1 as true RARE in regulating the Ssm, a novel retinoic acid-target gene in the mouse testis.

PubMed

Han, Kyuyong; Song, Haengseok; Moon, Irene; Augustin, Robert; Moley, Kelle; Rogers, Melissa; Lim, Hyunjung

2007-03-01

Various nuclear receptors form dimers to activate target genes via specific response elements located within promoters or enhancers. Retinoid X receptor (RXR) serves as a dimerization partner for many nuclear receptors including retinoic acid receptor (RAR) and peroxisome proliferator-activated receptor (PPAR). Dimers show differential preference towards directly repeated response elements with 1-5 nucleotide spacing, and direct repeat 1 (DR1) is a promiscuous element which recruits RAR/RXR, RXR/RXR, and PPAR/RXR in vitro. In the present investigation, we report identification of a novel RAR/RXR target gene which is regulated by DR1s in the promoter region. This gene, namely spermatocyte-specific marker (Ssm), recruits all the three combinations of nuclear receptors in vitro, but in vivo regulation is observed by trans-retinoic acid-activated RAR/RXR dimer. Indeed, chromatin immunoprecipitation experiment demonstrates binding of RARbeta and RXRalpha in the promoter region of the Ssm. Interestingly, expression of Ssm is almost exclusively observed in spermatocytes in the adult mouse testis, where RA signaling is known to regulate developmental program of male germ cells. The results show that Ssm is a RAR/RXR target gene uniquely using DR1 and exhibits stage-specific expression in the mouse testis with potential function in later stages of spermatogenesis. This finding exemplifies usage of DR1s as retinoic acid response element (RARE) under a specific in vivo context.

Retinoic Acid Receptor β: A Potential Therapeutic Target in Retinoic Acid Treatment of Endometrial Cancer.

PubMed

Tsuji, Keita; Utsunomiya, Hiroki; Miki, Yasuhiro; Hanihara, Mayu; Fue, Misaki; Takagi, Kiyoshi; Nishimoto, Mitsuo; Suzuki, Fumihiko; Yaegashi, Nobuo; Suzuki, Takashi; Ito, Kiyoshi

2017-05-01

Several studies have reported that retinoic acid (RA) might be used to treat malignancies. The effects of RA are mediated by the RA receptor (RAR), and RARα/RARβ especially acts as a tumor suppressor. However, little is known about its role in human endometrial cancer. In this study, we examined the effects of all-trans RA (ATRA) on progression of human endometrial cancer cell line, RL95-2 and Hec1A. We then examined the expression of RARα and RARβ in 50 endometrial cancer tissues by using immunohistochemistry. We found inhibitory effects of ATRA on cell proliferation, apoptosis, and migration in RL95-2 cells, but not in Hec1A cells. RARα or RARβ knockdown individually could not cancel out the inhibition of cell proliferation by ATRA in RL95-2 cells, but simultaneous knockdown of RARα and RARβ could block its effect on proliferation. RARα and RARβ knockdown dose dependently reduced the inhibition of migration by ATRA, but the effect was more pronounced with RARβ knockdown than with RARα knockdown. We confirmed that RARβ gene was directly regulated by ATRA in microarray and real-time reverse transcription polymerase chain reaction. Furthermore, the RARβ agonist (BMS453) significantly suppressed proliferation of RL95-2 cells. In immunohistochemical analysis, RARα expression was positively correlated with tumor grade, and RARβ showed the opposite tendency in endometrial cancer. Retinoic acid might have multiple antitumor effects, and RARβ may be a potent therapeutic target in RA treatment for endometrial cancers.

Normal neutrophil differentiation and secondary granule gene expression in the EML and MPRO cell lines.

PubMed

Lawson, N D; Krause, D S; Berliner, N

1998-11-01

The EML and MPRO cell lines express a dominant negative retinoic acid receptor alpha that causes a block at specific stages of myelopoiesis. The EML cell line is multipotent and gives rise to erythroid, lymphoid, and myeloid lineages depending on the presence of appropriate cytokines. The MPRO cell line is promyelocytic and undergoes neutrophilic differentiation when induced with all-trans retinoic acid in the presence of granulocyte/macrophage colony-stimulating factor. Previous studies have shown that both of these cell lines undergo morphological differentiation into neutrophils. In this study, we show that unlike other models of neutrophil differentiation such as NB4 and HL60, both EML and MPRO cell lines undergo complete, normal granulocytic differentiation programs. Similar to HL60, MPRO and EML induce expression of CD11b/CD18 and also exhibit downregulation of CD34 on differentiation. In contrast to HL60 and NB4, EML and MPRO cell lines coordinately upregulate secondary granule transcripts for lactoferrin and neutrophil gelatinase. Furthermore, we have confirmed previous observations that serum can induce a low level of differentiation in MPRO cells and that it is possible to grow these cells in serum-free medium, thereby eliminating this effect. Based on these studies, it appears that these lines can serve as a model for normal retinoic acid-induced neutrophil differentiation and provide insight into the role of the retinoic acid-responsive pathway in normal and leukemic myelopoiesis.

Characterization of cDNAs encoding the chick retinoic acid receptor gamma 2 and preferential distribution of retinoic acid receptor gamma transcripts during chick skin development.

PubMed

Michaille, J J; Blanchet, S; Kanzler, B; Garnier, J M; Dhouailly, D

1994-12-01

Retinoic acid receptors alpha, beta and gamma (RAR alpha, beta and gamma) are ligand-inductible transcriptional activators which belong to the steroid/thyroid hormone receptor superfamily. At least two major isoforms (1 and 2) of each RAR arise by differential use of two promoters and alternative splicing. In mouse, the three RAR genes are expressed in stage- and tissue-specific patterns during embryonic development. In order to understand the role of the different RARs in chick, RAR gamma 2 cDNAs were isolated from an 8.5-day (stage 35 of Hamburger and Hamilton) chick embryo skin library. The deduced chick RAR gamma 2 amino acid sequence displays uncommon features such as 21 specific amino acid replacements, 12 of them being clustered in the amino-terminal region (domains A2 and B), and a truncated acidic carboxy-terminal region (F domain). However, the pattern of RAR gamma expression in chick embryo resembles that reported in mouse, particularly in skin where RAR gamma expression occurs in both the dermal and epidermal layers at the beginning of feather formation, and is subsequently restricted to the differentiating epidermal cells. Northern blot analysis suggests that different RAR gamma isoforms could be successively required during chick development.

Potential for all-trans retinoic acid (tretinoin) to enhance interferon-alpha treatment response in chronic myelogenous leukemia, melanoma, myeloma and renal cell carcinoma.

PubMed

Kast, Richard E

2008-10-01

This note mechanistically accounts for recent unexplained findings that all-trans retinoic acid (ATRA, also termed tretinoin) exerts an anti-viral effect against hepatitis C virus (HCV) in chronically infected patients, in whom ATRA also showed synergy with interferon-alpha. How HCV replication was suppressed was unclear. Both effects of ATRA can be accounted for by ATRA's upregulation of RIG protein, an 18 kDa product of retinoic induced gene-1. Increased RIG then couples ATRA to increased Type 1 interferons' production. Details of this mechanism predict that ATRA will similarly augment interferon-a activity in treating chronic myelogenous leukemia, melanoma, myeloma and renal cell carcinoma and that the addition of ribavirin and/or bexarotene will each incrementally enhance interferon-a responses in these cancers.

Isotretinoin has no negative effect on attention, executive function and mood.

PubMed

Ergun, T; Seckin, D; Ozaydin, N; Bakar, Ö; Comert, A; Atsu, N; Demircay, Z; Yoney, H; Zaimoglu, S

2012-04-01

According to some animal data, impairments in learning and memory are seen with isotretinoin. Isotretinoin has been shown to affect human brain metabolism, but the data on human neural functions is lacking. To evaluate whether isotretinoin treatment affects cognitive functions, causes depression and anxiety or alters anger level and anger expression. Neuropsychological tests of attention and executive functions, behavioural tests measuring anger and depression and measures assessing acne severity were applied to 63 severe and/or resistant acne patients from four medical centres including one primary care institute and three university hospitals at the beginning, at the end of first month, third month and at end of treatment with isotretinoin. From a total of 63 patients, 15 missed the final visit and 48 were evaluated. Overall, 11 (six women, five men) and five (all women) patients reported anger and depression, respectively, during treatment. Eleven of these 16 patients improved spontaneously. No detrimental effects of isotretinoin treatment on either executive functions or mood were found. Several executive functions and control of anger trait were found to be improved. Clearing of acne was obtained in 94.6% of patients. Improvement of several measures may be related to learning effect of repeated testing. Investigating brain functions is a complex process and various methods can be used. The test battery used in this study, which is commonly used to evaluate mental status both in adults and children, did not show any negative effect of isotretinoin on executive functional parameters in acne patients. © 2011 The Authors. Journal of the European Academy of Dermatology and Venereology © 2011 European Academy of Dermatology and Venereology.

A novel unsaturated fatty acid hydratase toward C16 to C22 fatty acids from Lactobacillus acidophilus

PubMed Central

Hirata, Akiko; Kishino, Shigenobu; Park, Si-Bum; Takeuchi, Michiki; Kitamura, Nahoko; Ogawa, Jun

2015-01-01

Hydroxy FAs, one of the gut microbial metabolites of PUFAs, have attracted much attention because of their various bioactivities. The purpose of this study was to identify lactic acid bacteria with the ability to convert linoleic acid (LA) to hydroxy FAs. A screening process revealed that a gut bacterium, Lactobacillus acidophilus NTV001, converts LA mainly into 13-hydroxy-cis-9-octadecenoic acid and resulted in the identification of the hydratase responsible, fatty acid hydratase 1 (FA-HY1). Recombinant FA-HY1 was purified, and its enzymatic characteristics were investigated. FA-HY1 could convert not only C18 PUFAs but also C20 and C22 PUFAs. C18 PUFAs with a cis carbon-carbon double bond at the Δ12 position were converted into the corresponding 13-hydroxy FAs. Arachidonic acid and DHA were converted into the corresponding 15-hydroxy FA and 14-hydroxy FA, respectively. To the best of our knowledge, this is the first report of a bacterial FA hydratase that can convert C20 and C22 PUFAs into the corresponding hydroxy FAs. These novel hydroxy FAs produced by using FA-HY1 should contribute to elucidating the bioactivities of hydroxy FAs. PMID:25966711

Improved Outcomes With Retinoic Acid and Arsenic Trioxide Compared With Retinoic Acid and Chemotherapy in Non-High-Risk Acute Promyelocytic Leukemia: Final Results of the Randomized Italian-German APL0406 Trial.

PubMed

Platzbecker, Uwe; Avvisati, Giuseppe; Cicconi, Laura; Thiede, Christian; Paoloni, Francesca; Vignetti, Marco; Ferrara, Felicetto; Divona, Mariadomenica; Albano, Francesco; Efficace, Fabio; Fazi, Paola; Sborgia, Marco; Di Bona, Eros; Breccia, Massimo; Borlenghi, Erika; Cairoli, Roberto; Rambaldi, Alessandro; Melillo, Lorella; La Nasa, Giorgio; Fiedler, Walter; Brossart, Peter; Hertenstein, Bernd; Salih, Helmut R; Wattad, Mohammed; Lübbert, Michael; Brandts, Christian H; Hänel, Mathias; Röllig, Christoph; Schmitz, Norbert; Link, Hartmut; Frairia, Chiara; Pogliani, Enrico Maria; Fozza, Claudio; D'Arco, Alfonso Maria; Di Renzo, Nicola; Cortelezzi, Agostino; Fabbiano, Francesco; Döhner, Konstanze; Ganser, Arnold; Döhner, Hartmut; Amadori, Sergio; Mandelli, Franco; Ehninger, Gerhard; Schlenk, Richard F; Lo-Coco, Francesco

2017-02-20

Purpose The initial results of the APL0406 trial showed that the combination of all- trans-retinoic acid (ATRA) and arsenic trioxide (ATO) is at least not inferior to standard ATRA and chemotherapy (CHT) in first-line therapy of low- or intermediate-risk acute promyelocytic leukemia (APL). We herein report the final analysis on the complete series of patients enrolled onto this trial. Patients and Methods The APL0406 study was a prospective, randomized, multicenter, open-label, phase III noninferiority trial. Eligible patients were adults between 18 and 71 years of age with newly diagnosed, low- or intermediate-risk APL (WBC at diagnosis ≤ 10 × 10 9 /L). Overall, 276 patients were randomly assigned to receive ATRA-ATO or ATRA-CHT between October 2007 and January 2013. Results Of 263 patients evaluable for response to induction, 127 (100%) of 127 patients and 132 (97%) of 136 patients achieved complete remission (CR) in the ATRA-ATO and ATRA-CHT arms, respectively ( P = .12). After a median follow-up of 40.6 months, the event-free survival, cumulative incidence of relapse, and overall survival at 50 months for patients in the ATRA-ATO versus ATRA-CHT arms were 97.3% v 80%, 1.9% v 13.9%, and 99.2% v 92.6%, respectively ( P < .001, P = .0013, and P = .0073, respectively). Postinduction events included two relapses and one death in CR in the ATRA-ATO arm and two instances of molecular resistance after third consolidation, 15 relapses, and five deaths in CR in the ATRA-CHT arm. Two patients in the ATRA-CHT arm developed a therapy-related myeloid neoplasm. Conclusion These results show that the advantages of ATRA-ATO over ATRA-CHT increase over time and that there is significantly greater and more sustained antileukemic efficacy of ATO-ATRA compared with ATRA-CHT in low- and intermediate-risk APL.

Fred Hutchinson Cancer Research Center (FHCRC-1): Identification of drug targets for combination therapy with Retinoic Acid in Neuroblastoma | Office of Cancer Genomics

Cancer.gov

Retinoic Acid (RA) is employed in the clinic during the “consolidation” phase of treatment regimens for high-risk neuroblastoma.  While the addition of RA has greatly increased the survival of children with neuroblastoma, there is still a high frequency of relapse.  With the goal of identifying novel drug combinations that would enhance the effect of RA on neuroblastoma, an siRNA screen in the presence or absence of sub-lethal concentrations of RA was carried out.

Fred Hutchinson Cancer Research Center (FHCRC1): Identification of drug targets for combination therapy with Retinoic Acid in Neuroblastoma | Office of Cancer Genomics

Cancer.gov

Retinoic Acid (RA) is employed in the clinic during the “consolidation” phase of treatment regimens for high-risk neuroblastoma.  While the addition of RA has greatly increased the survival of children with neuroblastoma, there is still a high frequency of relapse.  With the goal of identifying novel drug combinations that would enhance the effect of RA on neuroblastoma, an siRNA screen in the presence or absence of sub-lethal concentrations of RA was carried out.

Persistent behavioral effects following early life exposure to retinoic acid or valproic acid in zebrafish

PubMed Central

Bailey, Jordan M.; Oliveri, Anthony N.; Karbhari, Nishika; Brooks, Roy A.J.; De La Rocha, Amberlene J.; Janardhan, Sheila; Levin, Edward D.

2015-01-01

BACKGROUND Moderate to severe dysregulation in retinoid signaling during early development is associated with a constellation of physical malformations and/or neural tube defects, including spina bifida. It is thought that more subtle dysregulation of this system, which might be achievable via dietary (i.e. hypervitaminosis A) or pharmacological (i.e. valproic acid) exposure in humans, will manifest on behavioral domains including sociability, without overt physical abnormalities. METHODS During early life, zebrafish were exposed to low doses of two chemicals that disrupt retinoid signaling. From 0-5 dpf, larvae were reared in aqueous solutions containing retinoic acid (0, 0.02, 0.2 or 2 nM) or valproic acid (0, 0.5, 5.0 or 50 uM). One cohort of zebrafish was assessed using a locomotor activity screen at 6-dpf; another was reared to adulthood and assessed using a neurobehavioral test battery (startle habituation, novel tank exploration, shoaling, and predator escape/avoidance). RESULTS There was no significant increase in the incidence of physical malformation among exposed fish compared to controls. Both retinoic acid and valproic acid exposures during development disrupted larval activity with persisting behavioral alterations later in life, primarily manifesting as decreased social affiliation. CONCLUSIONS Social behavior and some aspects of motor function were altered in exposed fish; the importance of examining emotional or psychological consequences of early life exposure to retinoid acting chemicals is discussed. PMID:26439099

Presenile diffuse familial sebaceous hyperplasia successfully treated with low-dose isotretinoin: A report of two cases and review of the published work.

PubMed

Liu, You-Chen Serena; Cheng, Yu-Pin; Liu, Chuan-I; Yang, Chin-Yi; Yang, Chia-Yi

2016-10-01

Presenile diffuse familial sebaceous hyperplasia (PDFSH) presents as extensive yellowish papules with central umbilication on the face without involvement of periorificial regions and occurs in adolescents or young adults with a positive family history. Thirteen cases of PDFSH have been reported in the English-language published work, 10 of which responded to oral isotretinoin from 0.5 to 1 mg/kg per day but recurrences were often observed. Herein, we report two cases of PDFSH, which were successfully managed without recurrence with prolonged low-dose isotretinoin (0.2 mg/kg per day, a cumulative dose of 41 and 64 mg/kg, respectively). Treatment protocols among different published works were reviewed to verify the efficacy of isotretinoin. © 2016 Japanese Dermatological Association.

Effects of isotretinoin on the platelet counts and the mean platelet volume in patients with acne vulgaris.

PubMed

Ataseven, Arzu; Ugur Bilgin, Aynur

2014-01-01

Aim. The aim of this study was to evaluate the platelet counts and the mean platelet volume in patients who received isotretinoin for the treatment of acne vulgaris. Method. A total of 110 patients were included in this retrospective study. Complete blood count parameters were recorded prior to and three-months following the treatment. Results. Both platelet counts and the mean platelet volume were significantly decreased following the treatment. No significant differences were noted on the levels of hemoglobin, hematocrit, and white blood cell count. Conclusion. Platelet counts and mean platelet volume significantly decreased following isotretinoin treatment. Since the decrease of platelet counts and the mean platelet volume was seen concomitantly, it is concluded that the effect of isotretinoin was through the suppression of bone marrow.

Tung tree (Vernicia fordii, Hemsl.) genome and transcriptome sequencing reveals coordinate upregulation of fatty acid beta-oxidation and triacylglycerol biosynthesis pathways during eleostearic acid accumulation in seeds

USDA-ARS?s Scientific Manuscript database

The tung tree (Vernicia fordii) is one of only a few plant species that produces high oil-yielding seeds rich in a-eleostearic acid (a-ESA, 18:3'9cis,11trans,13trans), a conjugated trienoic fatty acid with valuable industrial and medical properties. Previous attempts have been made to engineer tung...

Retinoic acid regulates cell-shape and -death of E-FABP (FABP5)-immunoreactive septoclasts in the growth plate cartilage of mice.

PubMed

Bando, Yasuhiko; Yamamoto, Miyuki; Sakiyama, Koji; Sakashita, Hide; Taira, Fuyoko; Miyake, Genki; Iseki, Shoichi; Owada, Yuji; Amano, Osamu

2017-09-01

Septoclasts, which are mononuclear and spindle-shaped cells with many processes, have been considered to resorb the transverse septa of the growth plate (GP) cartilage at the chondro-osseous junction (COJ). We previously reported the expression of epidermal-type fatty acid-binding protein (E-FABP, FABP5) and localization of peroxisome proliferator-activated receptor (PPAR)β/δ, which mediates the cell survival or proliferation, in septoclasts. On the other hand, retinoic acid (RA) can bind to E-FABP and is stored abundantly in the GP cartilage. From these information, it is possible to hypothesize that RA in the GP is incorporated into septoclasts during the cartilage resorption and regulates the growth and/or death of septoclasts. To clarify the mechanism of the cartilage resorption induced by RA, we administered an overdose of RA or its precursor vitamin A (VA)-deficient diet to young mice. In mice of both RA excess and VA deficiency, septoclasts decreased in the number and cell size in association with shorter and lesser processes than those in normal mice, suggesting a substantial suppression of resorption by septoclasts in the GP cartilage. Lack of PPARβ/δ-expression, TUNEL reaction, RA receptor (RAR)β, and cellular retinoic acid-binding protein (CRABP)-II were induced in E-FABP-positive septoclasts under RA excess, suggesting the growth arrest/cell-death of septoclasts, whereas cartilage-derived retinoic acid-sensitive protein (CD-RAP) inducing the cell growth arrest or morphological changes was induced in septoclasts under VA deficiency. These results support and do not conflict with our hypothesis, suggesting that endogenous RA in the GP is possibly incorporated in septoclasts and utilized to regulate the activity of septoclasts resorbing the GP cartilage.

Evaluation of thyroid function tests of acne vulgaris patients treated with systemic isotretinoin.

PubMed

Yıldırım, Neslihan; Doğan, Sibel; Atakan, Nilgün

2017-03-01

Isotretinoin is a systemic retinoid used to treat acne and it binds receptors which are the member of steroid-thyroid hormone superfamily. Certain types of retinoids may cause abnormalities in serum thyroid function tests (sTFTs) by suppressing thyroid stimulating hormone (TSH). However, it is uncertain whether systemic isotretinoin has any effect on sTFTs. The aim of the study was to find out if there is any alteration in sTFTs of patients with acne vulgaris treated with systemic isotretinoin. A total of 51 patients (male/female: 22/29) with severe acne vulgaris treated with a total dose of 120 mg/kg isotretinoin were included into the study prospectively. Serum free T3 (fT3), free T4 (fT4) and TSH levels were measured at baseline, 3rd and 6th months of treatment. Mean serum TSH levels at baseline, 3rd and 6th months of treatment were 1.57 ± 0.67, 2.07 ± 0.88 and 2.25 ± 0.86 uIU/mL, respectively. Mean serum TSH levels increased significantly following isotretinoin therapy (p < 0.01, p = 0.007 and p < 0.01, respectively). Mean serum fT3 levels at baseline, 3rd and 6th months of treatment were 3.59 ± 0.57, 3.19 ± 0.45 and 3.09 ± 0.61 pmol/L, respectively. Mean serum fT4 levels at baseline, 3rd and 6th months of treatment were 1.21 ± 0.19, 1.09 ± 0.16 and 1.11 ± 0.19 pmol/L, respectively. Mean serum fT3 and fT4 levels decreased significantly at 3rd and 6th months compared to baseline levels (p < 0.01 and p < 0.01, p < 0.01 and p = 0.001, respectively). Systemic isotretinoin therapy causes significant alterations in sTFTs. Dose dependent or long-term effects of systemic isotretinoin on sTFTs needs further evaluation.

Structures and physiological roles of 13 integral lipids of bovine heart cytochrome c oxidase

PubMed Central

Shinzawa-Itoh, Kyoko; Aoyama, Hiroshi; Muramoto, Kazumasa; Terada, Hirohito; Kurauchi, Tsuyoshi; Tadehara, Yoshiki; Yamasaki, Akiko; Sugimura, Takashi; Kurono, Sadamu; Tsujimoto, Kazuo; Mizushima, Tsunehiro; Yamashita, Eiki; Tsukihara, Tomitake; Yoshikawa, Shinya

2007-01-01

All 13 lipids, including two cardiolipins, one phosphatidylcholine, three phosphatidylethanolamines, four phosphatidylglycerols and three triglycerides, were identified in a crystalline bovine heart cytochrome c oxidase (CcO) preparation. The chain lengths and unsaturated bond positions of the fatty acid moieties determined by mass spectrometry suggest that each lipid head group identifies its specific binding site within CcOs. The X-ray structure demonstrates that the flexibility of the fatty acid tails facilitates their effective space-filling functions and that the four phospholipids stabilize the CcO dimer. Binding of dicyclohexylcarbodiimide to the O2 transfer pathway of CcO causes two palmitate tails of phosphatidylglycerols to block the pathway, suggesting that the palmitates control the O2 transfer process.The phosphatidylglycerol with vaccenate (cis-Δ11-octadecenoate) was found in CcOs of bovine and Paracoccus denitrificans, the ancestor of mitochondrion, indicating that the vaccenate is conserved in bovine CcO in spite of the abundance of oleate (cis-Δ9-octadecenoate). The X-ray structure indicates that the protein moiety selects cis-vaccenate near the O2 transfer pathway against trans-vaccenate. These results suggest that vaccenate plays a critical role in the O2 transfer mechanism. PMID:17332748

Isotretinoin and vitiligo: can chronic cheilitis cause koebnerization?

PubMed

Garner, Michael L; McShane, Diana B; Burkhart, Craig N; Morrell, Dean S

2015-01-01

Vitiligo after trauma through koebnerization is a widely reported phenomenon. Herein we present a case of vitiligo in an area of chronic cheilitis after isotretinoin treatment. © 2015 Wiley Periodicals, Inc.

Studies on long chain cis- and trans-acyl-CoA esters and Acyl-CoA dehydrogenase from rat heart mitochondria.

PubMed

Korsrud, G O; Conacher, H B; Jarvis, G A; Beare-Rogers, J L

1977-02-01

The beta-oxidation of long chain fatty acids was investigated in a preparation of rat heart mitochondria. The acyl-CoA esters of the cis and trans isomers of delta9-hexadecenoic, delta9-octadecenoic, delta11-eicosenoic, and delta13-docosenoic acids were prepared. Rates of the acyl-CoA reaction were determined with an extract from rat heart mitochondria. The apparent Michaelis constant (Km) and maximum velocity (Vmax) were calculated for each substrate. In general, apparent Vmax values decreased with increasing chain length of the monoenoic substrates. Reduced activity of acyl-CoA dehydrogenase with long chain acyl-CoA esters could have contributed to accumulation of lipids in hearts of rats fed diets containing long chain fatty acids.

Retinoic Acid Engineered Amniotic Membrane Used as Graft or Homogenate: Positive Effects on Corneal Alkali Burns.

PubMed

Joubert, Romain; Daniel, Estelle; Bonnin, Nicolas; Comptour, Aurélie; Gross, Christelle; Belville, Corinne; Chiambaretta, Frédéric; Blanchon, Loïc; Sapin, Vincent

2017-07-01

Alkali burns are the most common, severe chemical ocular injuries, their functional prognosis depending on corneal wound healing efficiency. The purpose of our study was to compare the benefits of amniotic membrane (AM) grafts and homogenates for wound healing in the presence or absence of previous all-trans retinoic acid (atRA) treatment. Fifty male CD1 mice with reproducible corneal chemical burn were divided into five groups, as follows: group 1 was treated with saline solution; groups 2 and 3 received untreated AM grafts or grafts treated with atRA, respectively; and groups 4 and 5 received untreated AM homogenates or homogenates treated with atRA, respectively. After 7 days of treatment, ulcer area and depth were measured, and vascular endothelial growth factor (VEGF) and matrix metalloproteinase 9 (MMP-9) were quantified. AM induction by atRA was confirmed via quantification of retinoic acid receptor β (RARβ), a well-established retinoic acid-induced gene. Significant improvements of corneal wound healing in terms of ulcer area and depth were obtained with both strategies. No major differences were found between the efficiency of AM homogenates and grafts. This positive action was increased when AM was pretreated with atRA. Furthermore, AM induced a decrease in VEGF and MMP-9 levels during the wound healing process. The atRA treatment led to an even greater decrease in the expression of both proteins. Amnion homogenate is as effective as AM grafts in promoting corneal wound healing in a mouse model. A higher positive effect was obtained with atRA treatment.

Isotretinoin (Accutane) and Pregnancy

MedlinePlus

... about all your breastfeeding questions. What about topical tretinoin? Topical tretinoin (Retin-A® and other brand names) is used ... skin to treat acne and other skin problems. Tretinoin is related to Vitamin A and isotretinoin. For ...

Assessment of the efficacy and safety of a combination of 2 topical retinoids (RetinSphere) in maintaining post-treatment response of acne to oral isotretinoin.

PubMed

Truchuelo, M T; Jiménez, N; Mavura, D; Jaén, P

2015-03-01

The high rate of relapse of acne lesions following oral isotretinoin treatment is a common problem which remains unsolved. To avoid or minimize relapses, topical retinoids have been used for many years as maintenance treatment. However, adverse effects frequently occur. To determine the efficacy and safety of a new retinoid combination (Retinsphere technology) in maintaining post-treatment response to oral isotretinoin. Prospective, randomized, double-blind and vehicle-controlled study of 30 patients with acne previously treated with isotretinoin. Treatment with the retinoid combination was applied to one side of the face and vehicle was applied to the other, once daily, for 3 months. Standardized photographs were taken using RBX technology at baseline, 1.5 months and 3 months. The primary efficacy endpoint was the appearance of relapse on the treated side compared to the vehicle-treated side. Other endpoints included lesion count, investigator-reported improvement, patient-reported improvement, impact on quality-of-life, and side effects. Although the majority of patients did not reach the total target dose of oral isotretinoin, the relapse rate was significantly lower on the retinoid-treated side compared to the vehicle-treated side. Likewise, improved lesion count and excellent tolerance were observed. This new retinoid combination (Retinsphere technology) were effective and safe as maintenance therapy after post-treatment response to oral isotretinoin in patients with acne. Copyright © 2014 Elsevier España, S.L.U. and AEDV. All rights reserved.

Differentiation of human SH-SY5Y neuroblastoma cells by all-trans retinoic acid activates the interleukin-18 system.

PubMed

Sallmon, Hannes; Hoene, Victoria; Weber, Sven C; Dame, Christof

2010-02-01

The clinical prognosis of children with high-stage neuroblastoma is still poor. Therapeutic approaches include surgery and cellular differentiation by retinoic acid, but also experimental interleukin-based immune modulation. However, the molecular mechanisms of all-trans retinoic acid (ATRA)-induced differentiation of neuroblastoma cells are incompletely understood. Herein, we examined the effect of ATRA on the activity of the interleukin-18 (IL-18) system in human SH-SY5Y neuroblastoma cells. It is shown that SH-SY5Y cells express IL-18 receptor (IL-18R) and the secreted antagonist IL-18-binding protein (IL-18BP), but no IL-18. SH-SY5Y cells are highly sensitive to ATRA treatment and react by cellular differentiation from a neuroblastic toward a more neuronal phenotype. This was associated with induction of IL-18 and reduction of IL-18BP expression, while IL-18R expression remained stable. Thereby, we identified the IL-18 system as a novel target of ATRA in neuroblastoma cells that might contribute to the therapeutic properties of retinoids in treatment of neuroblastoma.

Further evidence of a relationship between the retinoic acid receptor alpha locus and nonsyndromic cleft lip with or without cleft palate (CL [+-] P)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shaw, D.; Field, L.; Ray, A.

1993-11-01

Chenevix-Trench et al. (1992) reported a significant difference between nonsyndromic cleft lip with or without cleft palate (CL [+-] P) cases and unrelated controls in the frequency of alleles at the retinoic acid receptor alpha (RARA) PstI RFLP located at 17q21.1. They also observed borderline significant (P = .055) differences between allele frequencies in subjects with cleft lip and palate (CL + P) compared with those with cleft lip only (CL). Retinoic acid (RA) is a known teratogen capable of producing cleft palate in rodents (Abbott and Birnbaum 1990). Chenevix-Tench et al. (1992) hypothesized that variation in susceptibility to themore » effects of RA in humans may result from alterations at the RARA locus. We have investigated association and linkage between CL [+-] P and a microsatellite marker (D17S579) located at 17q21 (Hall et al. 1992), selected for its proximity to RARA, in 14 extended multiplex families from rural West Bengal, India.« less

Nanosecond pulsed electric field suppresses development of eyes and germ cells through blocking synthesis of retinoic acid in Medaka (Oryzias latipes).

PubMed

Shiraishi, Eri; Hosseini, Hamid; Kang, Dong K; Kitano, Takeshi; Akiyama, Hidenori

2013-01-01

Application of nanosecond pulsed electric fields (nsPEFs) has attracted rising attention in various scientific fields including medical, pharmacological, and biological sciences, although its effects and molecular mechanisms leading to the effects remain poorly understood. Here, we show that a single, high-intensity (10-30 kV/cm), 60-ns PEF exposure affects gene expression and impairs development of eyes and germ cells in medaka (Oryzias latipes). Exposure of early blastula stage embryos to nsPEF down-regulated the expression of several transcription factors which are essential for eye development, causing abnormal eye formation. Moreover, the majority of the exposed genetic female embryos showed a fewer number of germ cells similar to that of the control (unexposed) genetic male at 9 days post-fertilization (dpf). However, all-trans retinoic acid (atRA) treatment following the exposure rescued proliferation of germ cells and resumption of normal eye development, suggesting that the phenotypes induced by nsPEF are caused by a decrease of retinoic acid levels. These results confirm that nsPEFs induce novel effects during embryogenesis in medaka.

Retinoic acid temporally orchestrates colonization of the gut by vagal neural crest cells.

PubMed

Uribe, Rosa A; Hong, Stephanie S; Bronner, Marianne E

2018-01-01

The enteric nervous system arises from neural crest cells that migrate as chains into and along the primitive gut, subsequently differentiating into enteric neurons and glia. Little is known about the mechanisms governing neural crest migration en route to and along the gut in vivo. Here, we report that Retinoic Acid (RA) temporally controls zebrafish enteric neural crest cell chain migration. In vivo imaging reveals that RA loss severely compromises the integrity and migration of the chain of neural crest cells during the window of time window when they are moving along the foregut. After loss of RA, enteric progenitors accumulate in the foregut and differentiate into enteric neurons, but subsequently undergo apoptosis resulting in a striking neuronal deficit. Moreover, ectopic expression of the transcription factor meis3 and/or the receptor ret, partially rescues enteric neuron colonization after RA attenuation. Collectively, our findings suggest that retinoic acid plays a critical temporal role in promoting enteric neural crest chain migration and neuronal survival upstream of Meis3 and RET in vivo. Copyright © 2017 Elsevier Inc. All rights reserved.

Vitamin A-Retinoic Acid Signaling Regulates Hematopoietic Stem Cell Dormancy.

PubMed

Cabezas-Wallscheid, Nina; Buettner, Florian; Sommerkamp, Pia; Klimmeck, Daniel; Ladel, Luisa; Thalheimer, Frederic B; Pastor-Flores, Daniel; Roma, Leticia P; Renders, Simon; Zeisberger, Petra; Przybylla, Adriana; Schönberger, Katharina; Scognamiglio, Roberta; Altamura, Sandro; Florian, Carolina M; Fawaz, Malak; Vonficht, Dominik; Tesio, Melania; Collier, Paul; Pavlinic, Dinko; Geiger, Hartmut; Schroeder, Timm; Benes, Vladimir; Dick, Tobias P; Rieger, Michael A; Stegle, Oliver; Trumpp, Andreas

2017-05-18

Dormant hematopoietic stem cells (dHSCs) are atop the hematopoietic hierarchy. The molecular identity of dHSCs and the mechanisms regulating their maintenance or exit from dormancy remain uncertain. Here, we use single-cell RNA sequencing (RNA-seq) analysis to show that the transition from dormancy toward cell-cycle entry is a continuous developmental path associated with upregulation of biosynthetic processes rather than a stepwise progression. In addition, low Myc levels and high expression of a retinoic acid program are characteristic for dHSCs. To follow the behavior of dHSCs in situ, a Gprc5c-controlled reporter mouse was established. Treatment with all-trans retinoic acid antagonizes stress-induced activation of dHSCs by restricting protein translation and levels of reactive oxygen species (ROS) and Myc. Mice maintained on a vitamin A-free diet lose HSCs and show a disrupted re-entry into dormancy after exposure to inflammatory stress stimuli. Our results highlight the impact of dietary vitamin A on the regulation of cell-cycle-mediated stem cell plasticity. VIDEO ABSTRACT. Copyright © 2017. Published by Elsevier Inc.

Enhanced Oxidative Bioremediation of cis-dichloroethene (cis-DCE) and Vinyl Chloride (VC) using Electron Shuttles

DTIC Science & Technology

2009-07-01

1989) Abiotic Reduction of Nitro Aromatic Pesticides in Anaerobic Laboratory Systems. J, Agric, Food Chem, 37: 248. 13 Doménech-Carbó A., Doménech-Carbó...in general. Agricultural Use Humic acids have been used for decades as soil amendments and adjuvants for pesticide formulations for various food...necessary" to support an exception tolerance for pesticide formulations (EPA 2000, Federal Register, July 18, Vol 65, Number 138). Further, materials

Comparing the Efficacy of Low Dose and Conventional Dose of Oral Isotretinoin in Treatment of Moderate and Severe Acne Vulgaris.

PubMed

Faghihi, Gita; Mokhtari, Fatemeh; Fard, Nasrin Motamedi; Motamedi, Narges; Hosseini, Sayed Mohsen

2017-01-01

This study was conducted to compare the effect of low-dose isotretinoin with its conventional dose in patients with moderate and severe acne. This was a clinical trial conducted on 60 male and female patients with moderate and severe acne vulgaris. The patients were divided into two treatment groups: 0.5 mg/kg/day isotretinoin capsule and low-dose isotretinoin capsule (0.25 mg/kg/day). Patients in both groups received 6-month treatment. At the end of the 6 th month and 12 th month (6 months after the end of the treatment), they were examined again, and their improvement was determined and compared. The average severity of acne in the two treatment groups did not differ significantly within any of the study periods. The most common side effects were nose dryness in the low-dose group (17%) and hair thinning and loss in the conventional-dose group (33.2%), although all the patients had dry lips. According to the same severity of the acne in two groups in different study periods, as well as fewer side effects and more patients' satisfaction, the low-dose isotretinoin can be considered in the treatment of acne.

Outcomes of laser in situ keratomileusis and photorefractive keratectomy in patients taking isotretinoin.

PubMed

Ortega-Usobiaga, Julio; Llovet-Osuna, Fernando; Djodeyre, Mohammad Reza; Bilbao-Calabuig, Rafael; González-López, Félix; Llovet-Rausell, Andrea; Druchkiv, Vasyl

2018-05-14

To determine the functional outcomes of laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) in patients taking isotretinoin, which is contraindicated for these procedures. Multicentre, retrospective, interventional case series METHODS: All patients taking isotretinoin who underwent LASIK or PRK from January 2003 to September 2017 were included (group 1). Patients were compared with those undergoing LASIK or PRK who had taken isotretinoin previously but not in the previous 6 months (group 2). Patients were included consecutively. A total of 113 patients (219 eyes) were included. No significant intraoperative or postoperative complications were found. There were no significant differences between the groups in terms of visual acuity, postoperative spherical equivalent, efficacy index, predictability, or safety index. When only PRK patients were taken into account, the efficacy index (p: 0.017), postoperative sphere (p: 0.041), and postoperative astigmatism (p<0.001) were better in group 2, although the difference was not clinically relevant. In our experience, LASIK and PRK can be performed effectively and safely in selected patients taking isotretinoin. The absolute exclusion of certain systemic medications should be reconsidered. Copyright © 2018 Elsevier Inc. All rights reserved.

Lipid composition and chemotaxonomy of Pseudomonas putrefaciens (Alteromonas putrefaciens).

PubMed

Wilkinson, S G; Caudwell, P F

1980-06-01

The major polar lipids in cells of Pseudomonas putrefaciens NCIB 10472 grown on nutrient agar were phosphatidylethanolamine, phoisphatidylglycerol, a glucosyldiacylglycerol, a glucuronosyldiacylglycerol and an ornithine amide lipid. An additional phospholipid, tentatively identified as acyl phosphatidylglycerol or bis-phosphatidic acid, was a trace component of the wall lipids from broth cultures, which lacked the glycolipids and the ornithine amide lipid. The wall lipids from broth cultures of three further strains of P. putrefaciens (NCIB 10471, NCIB 11156 and NCTC 10737) contained all of the above lipids, and in two cases (strains NCIB 10471 and NCIB 11156) had an unusually high content of free fatty acid. Fatty acid compositions of the extractable lipids were qualitatively similar for all four strains: the major components were iso-pentadecanoic acid, pentadecanoic acid, a cis-heptadecenoic acid and a cis-hexadecenoic acid. Anteiso fatty acids were minor components in strain NCIB 10472. Lipid mixtures in which the ornithine amide lipid was present also contained small amounts of beta-hydroxy fatty acids: in strain NCIB 10472 the major ones were the straight-chain and iso-branched C16 acids. Lipopolysaccharides from all four strains had similar, complex fatty acid compositions. The major non-hydroxy acids were the straight-chain and iso-branched C13 acids. beta-Hydroxy acids common to all strains included the straight-chain C11, C12, C13, C14 and C15 acids, together with branched-chain C13 and C15 acids probably belonging to the iso series. The lipopolysaccharide from strains NCIB 10472 also contained C12 and C14 hydroxy acids of the same series, and small amounts of C13 and C15 beta-hydroxy acids probably belonging to the anteiso series. The close resemblance in both polar lipid and fatty acid compositions between strains of P. putrefaciens and Pseudomonas rubescens is further evidence that these species are synonymous. Significant differences between the lipids and fatty acids of P. putrefaciens and those reported for a strain of Alteromonas haloplanktis do not harmonize with a proposal to transfer the former organism to the genus Alteromonas.

Transcription Factor TBX1 Overexpression Induces Downregulation of Proteins Involved in Retinoic Acid Metabolism: A Comparative Proteomic Analysis

PubMed Central

Caterino, Marianna; Ruoppolo, Margherita; Fulcoli, Gabriella; Huynth, Tuong; Orrù, Stefania; Baldini, Antonio; Salvatore, Francesco

2009-01-01

TBX1 haploinsufficiency is considered a major contributor to the del22q11.2/DiGeorge syndrome (DGS) phenotype. We have used proteomic tools to look at all the major proteins involved in the TBX1-mediated pathways in an attempt to better understand the molecular interactions instrumental to its cellular functions. We found more than 90 proteins that could be targeted by TBX1 through different mechanisms. The most interesting observation is that overexpression of TBX1 results in down-regulation of two proteins involved in retinoic acid metabolism. PMID:19178302

Identifying the receptor subtype selectivity of retinoid X and retinoic acid receptors via quantum mechanics.

PubMed

Tsuji, Motonori; Shudo, Koichi; Kagechika, Hiroyuki

2017-03-01

Understanding and identifying the receptor subtype selectivity of a ligand is an important issue in the field of drug discovery. Using a combination of classical molecular mechanics and quantum mechanical calculations, this report assesses the receptor subtype selectivity for the human retinoid X receptor (hRXR) and retinoic acid receptor (hRAR) ligand-binding domains (LBDs) complexed with retinoid ligands. The calculated energies show good correlation with the experimentally reported binding affinities. The technique proposed here is a promising method as it reveals the origin of the receptor subtype selectivity of selective ligands.

Acute promyelocytic leukaemia: novel insights into the mechanisms of cure.

PubMed

de Thé, Hugues; Chen, Zhu

2010-11-01

The fusion oncogene, promyelocytic leukaemia (PML)-retinoic acid receptor-α (RARA), initiates acute promyelocytic leukaemia (APL) through both a block to differentiation and increased self-renewal of leukaemic progenitor cells. The current standard of care is retinoic acid (RA) and chemotherapy, but arsenic trioxide also cures many patients with APL, and an RA plus arsenic trioxide combination cures most patients. This Review discusses the recent evidence that reveals surprising new insights into how RA and arsenic trioxide cure this leukaemia, by targeting PML-RARα for degradation. Drug-triggered oncoprotein degradation may be a strategy that is applicable to many cancers.

NR4A orphan nuclear receptors influence retinoic acid and docosahexaenoic acid signaling via up-regulation of fatty acid binding protein 5

DOE Office of Scientific and Technical Information (OSTI.GOV)

Volakakis, Nikolaos; Joodmardi, Eliza; Perlmann, Thomas, E-mail: thomas.perlmann@licr.ki.se

2009-12-25

The orphan nuclear receptor (NR) Nurr1 is expressed in the developing and adult nervous system and is also induced as an immediate early gene in a variety of cell types. In silico analysis of human promoters identified fatty acid binding protein 5 (FABP5), a protein shown to enhance retinoic acid-mediated PPAR{beta}/{delta} signaling, as a potential Nurr1 target gene. Nurr1 has previously been implicated in retinoid signaling via its heterodimerization partner RXR. Since NRs are commonly involved in cross-regulatory control we decided to further investigate the regulatory relationship between Nurr1 and FABP5. FABP5 expression was up-regulated by Nurr1 and other NR4Amore » NRs in HEK293 cells, and Nurr1 was shown to activate and bind to the FABP5 promoter, supporting that FABP5 is a direct downstream target of NR4A NRs. We also show that the RXR ligand docosahexaenoic acid (DHA) can induce nuclear translocation of FABP5. Moreover, via up-regulation of FABP5 Nurr1 can enhance retinoic acid-induced signaling of PPAR{beta}/{delta} and DHA-induced activation of RXR. We also found that other members of the NR4A orphan NRs can up-regulate FABP5. Thus, our findings suggest that NR4A orphan NRs can influence signaling events of other NRs via control of FABP5 expression levels.« less

Comprehensive analysis of mycolic acid subclass and molecular species composition of Mycobacterium bovis BCG Tokyo 172 cell wall skeleton (SMP-105).

PubMed

Uenishi, Yuko; Fujita, Yukiko; Kusunose, Naoto; Yano, Ikuya; Sunagawa, Makoto

2008-02-01

The mycobacterial cell envelope consists of a characteristic cell wall skeleton (CWS), a mycoloyl arabinogalactan peptidoglycan complex, and related hydrophobic components that contribute to the cell surface properties. Since mycolic acids have recently been reported to play crucial roles in host immune response, detailed molecular characterization of mycolic acid subclasses and sub-subclasses of CWS from Mycobacterium bovis BCG Tokyo 172 (SMP-105) was performed. Mycolic acids were liberated by alkali hydrolysis from SMP-105, and their methyl esters were separated by silica gel TLC into three subclasses: alpha-, methoxy-, and keto-mycolates. Each mycolate subclass was further separated by silver nitrate (AgNO(3))-coated silica gel TLC into sub-subclasses. Molecular weights of individual mycolic acid were determined by MALDI-TOF mass spectrometry. alpha-Mycolates were sub-grouped into cis, cis-dicyclopropanoic (alpha1), and cis-monocyclopropanoic-cis-monoenoic (alpha2) series; methoxy-mycolates were sub-grouped into cis-monocyclopropanoic (m1), trans-monocyclopropanoic (m2), trans-monoenoic (m3), cis-monocyclopropanoic-trans-monoenoic (m4), cis-monoenoic (m5), and cis-monocyclopropanoic-cis-monoenoic (m6) series; and keto-mycolates were sub-grouped into cis-monocyclopropanoic (k1), trans-monocyclopropanoic (k2), trans-monoenoic (k3), cis-monoenoic (k4), and cis-monocyclopropanoic-cis-monoenoic (k5) series. The position of each functional group, including cyclopropane rings and methoxy and keto groups, was determined by analysis of the meromycolates with fast atom bombardment (FAB) mass spectrometry and FAB mass-mass spectrometry, and the cis/trans ratio of cyclopropane rings and double bonds were determined by NMR analysis of methyl mycolates. Mycolic acid subclass and molecular species composition of SMP-105 showed characteristic features including newly-identified cis-monocyclopropanoic-trans-monoenoic mycolic acid (m4).

Biosynthesis of cis,cis-muconic acid and its aromatic precursors, catechol and protocatechuic acid, from renewable feedstocks by Saccharomyces cerevisiae.

PubMed

Weber, Christian; Brückner, Christine; Weinreb, Sheila; Lehr, Claudia; Essl, Christine; Boles, Eckhard

2012-12-01

Adipic acid is a high-value compound used primarily as a precursor for the synthesis of nylon, coatings, and plastics. Today it is produced mainly in chemical processes from petrochemicals like benzene. Because of the strong environmental impact of the production processes and the dependence on fossil resources, biotechnological production processes would provide an interesting alternative. Here we describe the first engineered Saccharomyces cerevisiae strain expressing a heterologous biosynthetic pathway converting the intermediate 3-dehydroshikimate of the aromatic amino acid biosynthesis pathway via protocatechuic acid and catechol into cis,cis-muconic acid, which can be chemically dehydrogenated to adipic acid. The pathway consists of three heterologous microbial enzymes, 3-dehydroshikimate dehydratase, protocatechuic acid decarboxylase composed of three different subunits, and catechol 1,2-dioxygenase. For each heterologous reaction step, we analyzed several potential candidates for their expression and activity in yeast to compose a functional cis,cis-muconic acid synthesis pathway. Carbon flow into the heterologous pathway was optimized by increasing the flux through selected steps of the common aromatic amino acid biosynthesis pathway and by blocking the conversion of 3-dehydroshikimate into shikimate. The recombinant yeast cells finally produced about 1.56 mg/liter cis,cis-muconic acid.

Comparison of the stability of topical isotretinoin and topical tretinoin and their efficacy in acne.

PubMed

Elbaum, D J

1988-09-01

After 4 hours of exposure to incandescent light, 80% of 0.05% topical isotretinoin and 60% of 0.05% topical tretinoin preparations remained in their original form. In contrast, after 2 hours of exposure to fluorescent light only 25% of topical tretinoin and possibly 60% of topical isotretinoin remained in their original forms. Longer exposure to fluorescent light did not result in further breakdown, and the final breakdown of both preparations was similar. A 12-week, double-blind clinical trial comparing isotretinoin (0.05%) with tretinoin (0.05%) applied topically to patients with moderate acne was carried out. Both preparations caused significant reductions in papules and pustules. However, neither treatment was significantly superior to the other in the reduction of acne lesions. This may be because both preparations are rapidly broken down to similar products when exposed to fluorescent light.

Synthesis of cis-4-trifluoromethyl- and cis-4-difluoromethyl-l-pyroglutamic acids.

PubMed

Qiu, Xiao-Long; Qing, Feng-Ling

2003-05-02

Efforts to synthesize 4-trifluoromethyl- and 4-difluoromethyl-l-pyroglutamic acids are described. After many arduous efforts, we successfully synthesized our target molecules cis-4-trifluoromethyl-l-pyroglutamic acid 25 and cis-4-difluoromethyl-l-pyroglutamic acid 26 from trans-4-hydroxy-l-proline through oxidation of fluorinated prolinates with RuO(4).

Whole-Exome Sequencing in a South American Cohort Links ALDH1A3, FOXN1 and Retinoic Acid Regulation Pathways to Autism Spectrum Disorders.

PubMed

Moreno-Ramos, Oscar A; Olivares, Ana María; Haider, Neena B; de Autismo, Liga Colombiana; Lattig, María Claudia

2015-01-01

Autism spectrum disorders (ASDs) are a range of complex neurodevelopmental conditions principally characterized by dysfunctions linked to mental development. Previous studies have shown that there are more than 1000 genes likely involved in ASD, expressed mainly in brain and highly interconnected among them. We applied whole exome sequencing in Colombian-South American trios. Two missense novel SNVs were found in the same child: ALDH1A3 (RefSeq NM_000693: c.1514T>C (p.I505T)) and FOXN1 (RefSeq NM_003593: c.146C>T (p.S49L)). Gene expression studies reveal that Aldh1a3 and Foxn1 are expressed in ~E13.5 mouse embryonic brain, as well as in adult piriform cortex (PC; ~P30). Conserved Retinoic Acid Response Elements (RAREs) upstream of human ALDH1A3 and FOXN1 and in mouse Aldh1a3 and Foxn1 genes were revealed using bioinformatic approximation. Chromatin immunoprecipitation (ChIP) assay using Retinoid Acid Receptor B (Rarb) as the immunoprecipitation target suggests RA regulation of Aldh1a3 and Foxn1 in mice. Our results frame a possible link of RA regulation in brain to ASD etiology, and a feasible non-additive effect of two apparently unrelated variants in ALDH1A3 and FOXN1 recognizing that every result given by next generation sequencing should be cautiously analyzed, as it might be an incidental finding.

Isotretinoin: the ups are just as troubling as the downs.

PubMed

Truitt, Jay M; Reichenberg, Jason S; Sharghi, Kevin G; Sampson, Shirlene M; Roenigk, Randall K; Magid, Michelle

2018-08-01

Isotretinoin, previously marketed as Accutane®, is an oral retinoid medication that is used to treat acne and other cutaneous disorders. Although the data is conflicting, previous reports suggest a causal relationship between isotretinoin and depression. When reviewing these previous reports, many patients who were diagnosed as "depressed" did not undergo a thorough psychiatric evaluation and/or were not diagnosed according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders (DSM). These patients reported agitation, irritability, sleep disturbances, and aggression. We hypothesize that some patients previously reported as "depressed" may have been "misdiagnosed" and were actually experiencing symptoms of mania, mixed mood (depression and mania at the same time), or psychosis. An Ovid Medline and PubMed literature search of English language articles was performed using the keywords "isotretinoin", "retinoids", "mood", "psychiatric", "depression", "elevation", "bipolar", and "psychosis". Eleven case reports, three case series, three retrospective chart reviews, five drug registries, and two prospective studies were reviewed. We found that many of the patients labeled as "depressed", had signs of activation, agitation, elevated mood, and psychosis. We believe that many of these patients were most likely having manic or mixed mood episodes. These symptoms appeared to be more prevalent in patients with a personal or family history of mental illness. Isotretinoin may cause mood instability in both directions - depression and mania - especially in a predisposed population. With this in mind, we urge clinicians prescribing isotretinoin to focus on all psychiatric symptoms (not just depression) including mania, mixed mood, and psychosis, paying particular attention to individuals who have a personal or family history of psychiatric disease.

Formic acid dimers in a nitrogen matrix

NASA Astrophysics Data System (ADS)

Lopes, Susy; Fausto, Rui; Khriachtchev, Leonid

2018-01-01

Formic acid (HCOOH) dimers are studied by infrared spectroscopy in a nitrogen matrix and by ab initio calculations. We benefit from the use of a nitrogen matrix where the lifetime of the higher-energy (cis) conformer is very long (˜11 h vs. 7 min in an argon matrix). As a result, in a nitrogen matrix, a large proportion of the cis conformer can be produced by vibrational excitation of the lower-energy (trans) conformer. Three trans-trans, four trans-cis, and three cis-cis dimers are found in the experiments. The spectroscopic information on most of these dimers is enriched compared to the previous studies in an argon matrix. The cis-cis dimers of ordinary formic acid (without deuteration) are reported here for the first time. Several conformational processes are obtained using selective excitation by infrared light, some of them also for the first time. In particular, we report on the formation of cis-cis dimers upon vibrational excitation of trans-cis dimers. Tunneling decays of several dimers have been detected in the dark. The tunneling decay of cis-cis dimers of formic acid as well as the stabilization of cis units in cis-cis dimers is also observed for the first time.

Formic acid dimers in a nitrogen matrix.

PubMed

Lopes, Susy; Fausto, Rui; Khriachtchev, Leonid

2018-01-21

Formic acid (HCOOH) dimers are studied by infrared spectroscopy in a nitrogen matrix and by ab initio calculations. We benefit from the use of a nitrogen matrix where the lifetime of the higher-energy (cis) conformer is very long (∼11 h vs. 7 min in an argon matrix). As a result, in a nitrogen matrix, a large proportion of the cis conformer can be produced by vibrational excitation of the lower-energy (trans) conformer. Three trans-trans, four trans-cis, and three cis-cis dimers are found in the experiments. The spectroscopic information on most of these dimers is enriched compared to the previous studies in an argon matrix. The cis-cis dimers of ordinary formic acid (without deuteration) are reported here for the first time. Several conformational processes are obtained using selective excitation by infrared light, some of them also for the first time. In particular, we report on the formation of cis-cis dimers upon vibrational excitation of trans-cis dimers. Tunneling decays of several dimers have been detected in the dark. The tunneling decay of cis-cis dimers of formic acid as well as the stabilization of cis units in cis-cis dimers is also observed for the first time.

Lipopolysaccharide effects on the proliferation of NRK52E cells via alternations in gap-junction function.

PubMed

Hei, Ziqing; Zhang, Ailan; Wei, Jing; Gan, Xiaoliang; Wang, Yanling; Luo, Gangjian; Li, Xiaoyun

2012-07-01

Gap junctions regulate proper kidney function by facilitating intercellular communication, vascular conduction, and tubular purinergic signaling. However, no clear relationship has been described between gap-junction function and acute kidney injury induced by the endotoxin lipopolysaccharide (LPS). Normal rat kidney epithelial cells (NRK52E cells) were seeded at high and low densities to promote or impede gap-junction formation, respectively, and establish distinctive levels of intercellular communication in culture. Cells were then challenged with LPS at various concentrations (10-1,000 ng/mL). LPS-induced formation and function of gap junctions were assessed by measuring changes in cell proliferation and colony-forming rates, fluorescent dye transmission to adjacent cells, expression levels of connexin43, and repositioning of confluent cells in response to the gap junction inhibitor oleamide or agonist retinoic acid. The cell proliferation rate and colony-forming rate of high- and low-density NRK52E cells were decreased upon LPS challenge, in a dose-dependent manner. The colony-forming rate of confluent high-density cells was significantly lower than that of low-density cells. Oleamide treatment raised the LPS-induced colony-forming rate of high-density cells, whereas retinoic acid decreased the rate. Neither oleamide nor retinoic acid significantly affected the LPS-induced colony-forming rate of low-density cells. Fluorescence transmission of high-density cells was reduced by LPS challenge, in a dose-dependent manner, but inclusion of retinoic acid increased the LPS-induced transmission of fluorescence. LPS challenge of either high- or low-density NRK52E cells resulted in down-regulated connexin43 expression. Gap-junction function plays an important role in concentration-dependent cytotoxic effect of LPS on normal rat kidney cells in vitro.

A retinoic acid receptor β2 agonist reduces hepatic stellate cell activation in nonalcoholic fatty liver disease.

PubMed

Trasino, Steven E; Tang, Xiao-Han; Jessurun, Jose; Gudas, Lorraine J

2016-10-01

Hepatic stellate cells (HSCs) are an important cellular target for the development of novel pharmacological therapies to prevent and treat nonalcoholic fatty liver diseases (NAFLD). Using a high fat diet (HFD) model of NAFLD, we sought to determine if synthetic selective agonists for retinoic acid receptor β2 (RARβ2) and RARγ can mitigate HSC activation and HSC relevant signaling pathways during early stages of NAFLD, before the onset of liver injury. We demonstrate that the highly selective RARβ2 agonist, AC261066, can reduce the activation of HSCs, marked by decreased HSC expression of α-smooth muscle actin (α-SMA), in mice with HFD-induced NAFLD. Livers of HFD-fed mice treated with AC261066 exhibited reduced steatosis, oxidative stress, and expression of pro-inflammatory mediators, such as tumor necrosis factor-alpha (TNFα), interleukin 1β (IL-1β), and monocyte chemotactic protein-1 (MCP-1). Kupffer cell (macrophage) expression of transforming growth factor-β1 (TGF-β1), which plays a critical role in early HSC activation, was markedly reduced in AC261066-treated, HFD-fed mice. In contrast, HFD-fed mice treated with an RARγ agonist (CD1530) showed no decreases in steatosis, HSC activation, or Kupffer cell TGF-β1 levels. In conclusion, our data demonstrate that RARβ2 is an attractive target for development of NAFLD therapies. • Hepatic stellate cells (HSCs) are an important pharmacological target for the prevention of nonalcoholic fatty liver diseases (NAFLD). • Retinoids and retinoic acid receptors (RARs) possess favorable metabolic modulating properties. • We show that an agonist for retinoic acid receptor-β2 (RARβ2), but not RARγ, mitigates HSC activation and NAFLD.

Retinoids induce integrin-independent lymphocyte adhesion through RAR-α nuclear receptor activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whelan, Jarrett T.; Wang, Lei; Chen, Jianming

2014-11-28

Highlights: • Transcription and translation are required for retinoid-induced lymphocyte adhesion. • RAR activation is sufficient to induced lymphocyte cell adhesion. • Vitamin D derivatives inhibit RAR-prompted lymphocyte adhesion. • Adhesion occurs through a novel binding site within ADAM disintegrin domains. • RARα is a key nuclear receptor for retinoid-dependent lymphocyte cell adhesion. - Abstract: Oxidative metabolites of vitamin A, in particular all-trans-retinoic acid (atRA), have emerged as key factors in immunity by specifying the localization of immune cells to the gut. Although it is appreciated that isomers of retinoic acid activate the retinoic acid receptor (RAR) and retinoid Xmore » receptor (RXR) family of nuclear receptors to elicit cellular changes, the molecular details of retinoic acid action remain poorly defined in immune processes. Here we employ a battery of agonists and antagonists to delineate the specific nuclear receptors utilized by retinoids to evoke lymphocyte cell adhesion to ADAM (adisintegrin and metalloprotease) protein family members. We report that RAR agonism is sufficient to promote immune cell adhesion in both immortal and primary immune cells. Interestingly, adhesion occurs independent of integrin function, and mutant studies demonstrate that atRA-induced adhesion to ADAM members required a distinct binding interface(s) as compared to integrin recognition. Anti-inflammatory corticosteroids as well as 1,25-(OH){sub 2}D{sub 3}, a vitamin D metabolite that prompts immune cell trafficking to the skin, potently inhibited the observed adhesion. Finally, our data establish that induced adhesion was specifically attributable to the RAR-α receptor isotype. The current study provides novel molecular resolution as to which nuclear receptors transduce retinoid exposure into immune cell adhesion.« less

The dual nature of retinoic acid in pemphigus and its therapeutic potential: Special focus on all-trans Retinoic Acid.

PubMed

Tavakolpour, Soheil; Daneshpazhooh, Maryam; Mahmoudi, Hamid Reza; Balighi, Kamran

2016-07-01

The efficient treatment of pemphigus with no certain side effect remained a controversial issue. Although there are various options for controlling disease severity, the majority of them may cause serious side effects. Retinoic acid (RA), an active metabolite converted from vitamin A, plays an active role in immune functions. Effects of RA, especially all-trans-Retinoic Acid (ATRA) on different types of cells involved in immune responses were analyzed in vitro and in vivo. RAs could affect the differentiation of T helper (Th) cells, B cells responses, stabilization of both natural regulatory T cells (nTregs) and regulatory B cells (Bregs) populations, and regulating the expression of critical genes in immune responses. The role of RA, based on major immune cells involved in pemphigus has not been addressed so far. In this study, we sought to determine the possible effects of RA, with a special focus on ATRA in pemphigus. All the evidences of ATRA effects on the immune system were collected and their association with the pemphigus was analyzed. According to the previous results, ATRA causes a decline in Th17 populations; increase in CD4+ induced regulatory T cells (iTregs), stabilization of nTregs, and promotion of suppressive B cells, which are critical in the improvement of pemphigus. Nevertheless, it also causes shifting of the Th1:Th2 balance toward Th2 cells, which is not favorable for pemphigus patients. In conclusion, ATRA acts via different ways in pemphigus. Due to increase in the suppressive function via iTregs, nTregs, and Bregs, it is suggested that patients with pemphigus may benefit from systemic ATRA therapy. To clarify this issue, further studies, such as clinical trials are needed. Copyright © 2016 Elsevier B.V. All rights reserved.

Short communication: Effects of diets containing supplemental fats on ruminal fermentation and milk odd- and branched-chain fatty acids in dairy cows.

PubMed

Vazirigohar, M; Dehghan-Banadaky, M; Rezayazdi, K; Nejati-Javaremi, A; Mirzaei-Alamouti, H; Patra, A K

2018-07-01

There is a growing interest in odd- and branched-chain fatty acids (OBCFA) in milk following reports that several branched-chain fatty acids (FA) have health promoting effects, and certain milk OBCFA could serve as a biomarker to assess ruminal function. Twenty-four Holstein cows were fed 3 low-forage diets containing 30 g/kg of dry matter of prilled palm fat (PPF), sunflower oil (SO), or an equal mixture of both fats (experiment 1) or 3 diets containing 30 g/kg of dry matter of SO with a forage-to-concentrate ratio of 39:61, 44:56, or 48:52 (Experiment 2); diets were fed to investigate milk OBCFA composition and to explore the relationships between ruminal VFA and milk OBCFA using principal component analysis. Including SO in diets decreased yields of milk 13:0 anteiso, 15:0 anteiso, 15:0, 17:0, cis-9 15:1, and cis-9 17:1 compared with PPF. The molar proportion of ruminal propionate was the lowest and the yields of milk 14:0 iso and 16:0 iso were the greatest with the diet containing both fat supplements. Replacing concentrate with forages linearly increased ruminal acetate and yields of milk 13:0 iso, 14:0 iso, 15:0 iso, 16:0 iso, 17:0 iso, 13:0 anteiso, 15:0 anteiso, 15:0, 17:0, cis-9 15:1, and cis-9 17:1. The principal component analysis revealed that ruminal molar proportion of acetate related to concentrations of milk iso FA containing <17-carbon, whereas ruminal propionate related to milk 15:0, 17:0, cis-9 15:1, and cis-9 17:1, with the stronger correlations between milk OBCFA and ruminal acetate than propionate. No associations were found between ruminal molar proportion of butyrate and milk OBCFA concentrations. The results suggest that complete replacement of PPF with SO at 30 g/kg of dry matter in low-forage diets is not an effective strategy to enhance bioactive branched-chain FA in milk, rather this feeding practice lowers anteiso FA in milk; however, increasing forage proportion in diets containing SO enhances several iso and anteiso FA in milk. The milk OBCFA concentrations have stronger correlations with ruminal acetate molar proportion than with propionate or butyrate in cows fed diets containing supplemental fats. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Purification and characterization of monoclonal antibodies to alpha-linolenic acid.

PubMed

Buffière, F; Cook-Moreau, J; Gualde, N; Rigaud, M

1989-01-01

The covalently linked antigenic complex, bovine serum albumin-alpha-linolenic acid, was used to immunize Balb/c mice against the hapten. Hybridization between splenocytes and the myeloma cell line, P 3 X63 Ag 8,651, resulted in stable clones synthesizing monoclonal antibodies (Mab) that were subsequently purified and characterized. Four Mab (A, B, C, D) were retained and their specificities studied by ELISA. Antibody D only recognized 18-carbon fatty acids having a cis,cis,-cis-1,4,7 unsaturated system in the omega-3 position: it was specific for alpha-linolenic acid. B recognized all fatty acids containing the structure cis,cis,cis-1,4,7-octatriene. A and C recognized polyunsaturated fatty acids with a degree of unsaturation superior to two double bonds.

Second-order standard addition for deconvolution and quantification of fatty acids of fish oil using GC-MS.

PubMed

Vosough, Maryam; Salemi, Amir

2007-08-15

In the present work two second-order calibration methods, generalized rank annihilation method (GRAM) and multivariate curve resolution-alternating least square (MCR-ALS) have been applied on standard addition data matrices obtained by gas chromatography-mass spectrometry (GC-MS) to characterize and quantify four unsaturated fatty acids cis-9-hexadecenoic acid (C16:1omega7c), cis-9-octadecenoic acid (C18:1omega9c), cis-11-eicosenoic acid (C20:1omega9) and cis-13-docosenoic acid (C22:1omega9) in fish oil considering matrix interferences. With these methods, the area does not need to be directly measured and predictions are more accurate. Because of non-trilinear conditions of GC-MS data matrices, at first MCR-ALS and GRAM have been used on uncorrected data matrices. In comparison to MCR-ALS, biased and imprecise concentrations (%R.S.D.=27.3) were obtained using GRAM without correcting the retention time-shift. As trilinearity is the essential requirement for implementing GRAM, the data need to be corrected. Multivariate rank alignment objectively corrects the run-to-run retention time variations between sample GC-MS data matrix and a standard addition GC-MS data matrix. Then, two second-order algorithms have been compared with each other. The above algorithms provided similar mean predictions, pure concentrations and spectral profiles. The results validated using standard mass spectra of target compounds. In addition, some of the quantification results were compared with the concentration values obtained using the selected mass chromatograms. As in the case of strong peak-overlap and the matrix effect, the classical univariate method of determination of the area of the peaks of the analytes will fail, the "second-order advantage" has solved this problem successfully.

Comparing the Efficacy of Low Dose and Conventional Dose of Oral Isotretinoin in Treatment of Moderate and Severe Acne Vulgaris

PubMed Central

Faghihi, Gita; Mokhtari, Fatemeh; Fard, Nasrin Motamedi; Motamedi, Narges; Hosseini, Sayed Mohsen

2017-01-01

Objective: This study was conducted to compare the effect of low-dose isotretinoin with its conventional dose in patients with moderate and severe acne. Methods: This was a clinical trial conducted on 60 male and female patients with moderate and severe acne vulgaris. The patients were divided into two treatment groups: 0.5 mg/kg/day isotretinoin capsule and low-dose isotretinoin capsule (0.25 mg/kg/day). Patients in both groups received 6-month treatment. At the end of the 6th month and 12th month (6 months after the end of the treatment), they were examined again, and their improvement was determined and compared. Findings: The average severity of acne in the two treatment groups did not differ significantly within any of the study periods. The most common side effects were nose dryness in the low-dose group (17%) and hair thinning and loss in the conventional-dose group (33.2%), although all the patients had dry lips. Conclusion: According to the same severity of the acne in two groups in different study periods, as well as fewer side effects and more patients' satisfaction, the low-dose isotretinoin can be considered in the treatment of acne. PMID:29417084

Treatment of refractory undifferentiated acute myelogenous leukemia with all-trans-retinoic acid.

PubMed

Griggs, J J; Henley, S E; Rowe, J M

1994-02-01

A patient is described with undifferentiated acute myeloblastic leukemia refractory to two courses of daunorubicin and cytosine arabinoside. Because some the myeloblasts developed morphologic features of promyelocytes, the patient was treated with all-trans-retinoic acid (ATRA) in an attempt to promote maturation. Cytogenetic studies and sensitive molecular analysis did not reveal any abnormality classically associated with acute promyelocytic leukemia. Serial bone marrow biopsies demonstrated myeloid maturation, and the patient uneventfully went into a sustained complete remission. A review of the literature confirms this to be an apparently hitherto undescribed response to ATRA that may have therapeutic implications in similar patients.

Rational design of a colorimetric pH sensor from a soluble retinoic acid chaperone.

PubMed

Berbasova, Tetyana; Nosrati, Meisam; Vasileiou, Chrysoula; Wang, Wenjing; Lee, Kin Sing Stephen; Yapici, Ipek; Geiger, James H; Borhan, Babak

2013-10-30

Reengineering of cellular retinoic acid binding protein II (CRABPII) to be capable of binding retinal as a protonated Schiff base is described. Through rational alterations of the binding pocket, electrostatic perturbations of the embedded retinylidene chromophore that favor delocalization of the iminium charge lead to exquisite control in the regulation of chromophoric absorption properties, spanning the visible spectrum (474-640 nm). The pKa of the retinylidene protonated Schiff base was modulated from 2.4 to 8.1, giving rise to a set of proteins of varying colors and pH sensitivities. These proteins were used to demonstrate a concentration-independent, ratiometric pH sensor.

Retinoic Acid-Related Orphan Receptors (RORs): Regulatory Functions in Immunity, Development, Circadian Rhythm, and Metabolism

PubMed Central

Cook, Donald N.; Kang, Hong Soon; Jetten, Anton M.

2015-01-01

In this overview, we provide an update on recent progress made in understanding the mechanisms of action, physiological functions, and roles in disease of retinoic acid related orphan receptors (RORs). We are particularly focusing on their roles in the regulation of adaptive and innate immunity, brain function, retinal development, cancer, glucose and lipid metabolism, circadian rhythm, metabolic and inflammatory diseases and neuropsychiatric disorders. We also summarize the current status of ROR agonists and inverse agonists, including their regulation of ROR activity and their therapeutic potential for management of various diseases in which RORs have been implicated. PMID:26878025

Restoration of promyelocytic leukemia protein-nuclear bodies in neuroblastoma cells enhances retinoic acid responsiveness.

PubMed

Yu, Jiang Hong; Nakajima, Ayako; Nakajima, Hiroshi; Diller, Lisa R; Bloch, Kenneth D; Bloch, Donald B

2004-02-01

Neuroblastoma is the most common solid tumor of infancy and is believed to result from impaired differentiation of neuronal crest embryonal cells. The promyelocytic leukemia protein (PML)-nuclear body is a cellular structure that is disrupted during the pathogenesis of acute promyelocytic leukemia, a disease characterized by impaired myeloid cell differentiation. During the course of studies to examine the composition and function of PML-nuclear bodies, we observed that the human neuroblastoma cell line SH-SY5Y lacked these structures and that the absence of PML-nuclear bodies was a feature of N- and I-type, but not S-type, neuroblastoma cell lines. Induction of neuroblastoma cell differentiation with 5-bromo-2'deoxyuridine, all-trans-retinoic acid, or IFN-gamma induced PML-nuclear body formation. PML-nuclear bodies were not detected in tissue sections prepared from undifferentiated neuroblastomas but were present in neuroblasts in differentiating tumors. Expression of PML in neuroblastoma cells restored PML-nuclear bodies, enhanced responsiveness to all-trans-retinoic acid, and induced cellular differentiation. Pharmacological therapies that increase PML expression may prove to be important components of combined modalities for the treatment of neuroblastoma.

Retinoic acid signaling pathways in development and diseases.

PubMed

Das, Bhaskar C; Thapa, Pritam; Karki, Radha; Das, Sasmita; Mahapatra, Sweta; Liu, Ting-Chun; Torregroza, Ingrid; Wallace, Darren P; Kambhampati, Suman; Van Veldhuizen, Peter; Verma, Amit; Ray, Swapan K; Evans, Todd

2014-01-15

Retinoids comprise a group of compounds each composed of three basic parts: a trimethylated cyclohexene ring that is a bulky hydrophobic group, a conjugated tetraene side chain that functions as a linker unit, and a polar carbon-oxygen functional group. Biochemical conversion of carotenoid or other retinoids to retinoic acid (RA) is essential for normal regulation of a wide range of biological processes including development, differentiation, proliferation, and apoptosis. Retinoids regulate various physiological outputs by binding to nuclear receptors called retinoic acid receptors (RARs) and retinoid X receptors (RXRs), which themselves are DNA-binding transcriptional regulators. The functional response of RA and their receptors are modulated by a host of coactivators and corepressors. Retinoids are essential in the development and function of several organ systems; however, deregulated retinoid signaling can contribute to serious diseases. Several natural and synthetic retinoids are in clinical use or undergoing trials for treating specific diseases including cancer. In this review, we provide a broad overview on the importance of retinoids in development and various diseases, highlighting various retinoids in the drug discovery process, ranging all the way from retinoid chemistry to clinical uses and imaging. Copyright © 2013 Elsevier Ltd. All rights reserved.

Metformin inhibition of neuroblastoma cell proliferation is differently modulated by cell differentiation induced by retinoic acid or overexpression of NDM29 non-coding RNA.

PubMed

Costa, Delfina; Gigoni, Arianna; Würth, Roberto; Cancedda, Ranieri; Florio, Tullio; Pagano, Aldo

2014-01-01

Metformin is a widely used oral hypoglycemizing agent recently proposed as potential anti-cancer drug. In this study we report the antiproliferative effect of metformin treatment in a high risk neuroblastoma cell model, focusing on possible effects associated to different levels of differentiation and/or tumor initiating potential. Antiproliferative and cytotoxic effects of metformin were tested in human SKNBE2 and SH-SY5Y neuroblastoma cell lines and in SKNBE2 cells in which differentiation is induced by retinoic acid treatment or stable overexpression of NDM29 non-coding RNA, both conditions characterized by a neuron-like differentiated phenotype. We found that metformin significantly inhibits the proliferation of NB cells, an effect that correlates with the inhibition of Akt, while AMPK activity resulted unchanged. Notably, metformin effects were modulated in a different ways by differentiating stimuli, being abolished after retinoic acid treatment but potentiated by overexpression of NDM29. These data suggest the efficacy of metformin as neuroblastoma anticancer agent, and support the requirement of further studies on the possible role of the differentiation status on the antiproliferative effects of this drug.

A New Module in Neural Differentiation Control: Two MicroRNAs Upregulated by Retinoic Acid, miR-9 and -103, Target the Differentiation Inhibitor ID2

PubMed Central

Savino, Mauro; Laneve, Pietro; Caffarelli, Elisa; Nasi, Sergio

2012-01-01

The transcription factor ID2 is an important repressor of neural differentiation strongly implicated in nervous system cancers. MicroRNAs (miRNAs) are increasingly involved in differentiation control and cancer development. Here we show that two miRNAs upregulated on differentiation of neuroblastoma cells – miR-9 and miR-103 – restrain ID2 expression by directly targeting the coding sequence and 3′ untranslated region of the ID2 encoding messenger RNA, respectively. Notably, the two miRNAs show an inverse correlation with ID2 during neuroblastoma cell differentiation induced by retinoic acid. Overexpression of miR-9 and miR-103 in neuroblastoma cells reduces proliferation and promotes differentiation, as it was shown to occur upon ID2 inhibition. Conversely, an ID2 mutant that cannot be targeted by either miRNA prevents retinoic acid-induced differentiation more efficient than wild-type ID2. These findings reveal a new regulatory module involving two microRNAs upregulated during neural differentiation that directly target expression of the key differentiation inhibitor ID2, suggesting that its alteration may be involved in neural cancer development. PMID:22848373

A new module in neural differentiation control: two microRNAs upregulated by retinoic acid, miR-9 and -103, target the differentiation inhibitor ID2.

PubMed

Annibali, Daniela; Gioia, Ubaldo; Savino, Mauro; Laneve, Pietro; Caffarelli, Elisa; Nasi, Sergio

2012-01-01

The transcription factor ID2 is an important repressor of neural differentiation strongly implicated in nervous system cancers. MicroRNAs (miRNAs) are increasingly involved in differentiation control and cancer development. Here we show that two miRNAs upregulated on differentiation of neuroblastoma cells--miR-9 and miR-103--restrain ID2 expression by directly targeting the coding sequence and 3' untranslated region of the ID2 encoding messenger RNA, respectively. Notably, the two miRNAs show an inverse correlation with ID2 during neuroblastoma cell differentiation induced by retinoic acid. Overexpression of miR-9 and miR-103 in neuroblastoma cells reduces proliferation and promotes differentiation, as it was shown to occur upon ID2 inhibition. Conversely, an ID2 mutant that cannot be targeted by either miRNA prevents retinoic acid-induced differentiation more efficient than wild-type ID2. These findings reveal a new regulatory module involving two microRNAs upregulated during neural differentiation that directly target expression of the key differentiation inhibitor ID2, suggesting that its alteration may be involved in neural cancer development.

Retinoic Acid as a Modulator of T Cell Immunity

PubMed Central

Bono, Maria Rosa; Tejon, Gabriela; Flores-Santibañez, Felipe; Fernandez, Dominique; Rosemblatt, Mario; Sauma, Daniela

2016-01-01

Vitamin A, a generic designation for an array of organic molecules that includes retinal, retinol and retinoic acid, is an essential nutrient needed in a wide array of aspects including the proper functioning of the visual system, maintenance of cell function and differentiation, epithelial surface integrity, erythrocyte production, reproduction, and normal immune function. Vitamin A deficiency is one of the most common micronutrient deficiencies worldwide and is associated with defects in adaptive immunity. Reports from epidemiological studies, clinical trials and experimental studies have clearly demonstrated that vitamin A plays a central role in immunity and that its deficiency is the cause of broad immune alterations including decreased humoral and cellular responses, inadequate immune regulation, weak response to vaccines and poor lymphoid organ development. In this review, we will examine the role of vitamin A in immunity and focus on several aspects of T cell biology such as T helper cell differentiation, function and homing, as well as lymphoid organ development. Further, we will provide an overview of the effects of vitamin A deficiency in the adaptive immune responses and how retinoic acid, through its effect on T cells can fine-tune the balance between tolerance and immunity. PMID:27304965

SIGNALLING THROUGH RETINOIC ACID RECEPTORS IN CARDIAC DEVELOPMENT: DOING THE RIGHT THINGS AT THE RIGHT TIMES

PubMed Central

Xavier-Neto, José; Costa, Ângela M. Sousa; Figueira, Ana Carolina M.; Caiaffa, Carlo Donato; do Amaral, Fabio Neves; Peres, Lara Maldanis Cerqueira; da Silva, Bárbara Santos Pires; Santos, Luana Nunes; Moise, Alexander R.; Castillo, Hozana Andrade

2015-01-01

Retinoic acid (RA) is a terpenoid that is synthesized from Vitamin A/retinol (ROL) and binds to the nuclear receptors retinoic acid receptor (RAR)/retinoid X receptor (RXR) to control multiple developmental processes in vertebrates. The available clinic and experimental data provide uncontested evidence for the pleiotropic roles of RA signalling in development of multiple embryonic structures and organs such eyes, central nervous system, gonads, lungs and heart. The development of any of these above-mentioned embryonic organ systems can be effectively utilized to showcase the many strategies utilized by RA signalling. However, it is very likely that the strategies employed to transfer RA signals during cardiac development comprise the majority of the relevant and sophisticated ways through which retinoid signals can be conveyed in a complex biological system. Here, we provide the reader with arguments indicating that RA signalling is exquisitely regulated according to specific phases of cardiac development and that RA signalling itself is one of the major regulators of the timing of cardiac morphogenesis and differentiation. We will focus on the role of signalling by RA receptors (RARs) in early phases of heart development. PMID:25134739

A randomized comparative trial of two low-dose oral isotretinoin regimens in moderate to severe acne vulgaris

PubMed Central

Dhaked, Daulat Ram; Meena, Ram Singh; Maheshwari, Anshul; Agarwal, Uma Shankar; Purohit, Saroj

2016-01-01

Background: Oral isotretinoin is highly effective in all forms and grades of acne, even in lower dosages (<0.5 mg/kg/day). There is a paucity of comparative data on the various low-dose regimens of oral isotretinoin in the Indian literature. Objectives: To assess and compare the efficacy and tolerability of two low-dose oral isotretinoin treatment regimens (20 mg daily and 20 mg alternate days) in moderate to severe acne vulgaris. Materials and Methods: A total of 240 patients with moderate to severe acne vulgaris were selected and randomized into two groups and treated with a fixed dose of 20 mg of isotretinoin (Group A - daily and Group B - alternate days) for 24 weeks and followed up for 12 weeks post therapy. Results: A total of 234 patients completed the study. At the end of therapy, decrease in the total acne loads up to 98.99% (Group A) and 97.69% (Group B) was achieved from the baseline (P < 0.01), excellent response was observed in 98.3% (Group A) and 93.96% (Group B) patients (P = 0.166). In the severe acne, Group A performed significantly better than Group B until the end of 36 weeks. While in the moderate acne, significant difference in the response between both groups was observed only up to 12 weeks. No serious side effect was observed. Conclusion: Both isotretinoin regimens were well tolerated and found to be an effective treatment for moderate to severe acne vulgaris. However, in moderate acne 20 mg alternate day regimen may be preferred. A 20 mg daily regimen is a better choice for severe acne in terms of response. Limitation: Small sample size and short follow-up period. PMID:27730033

Formation of conjugated delta8,delta10-double bonds by delta12-oleic-acid desaturase-related enzymes: biosynthetic origin of calendic acid.

PubMed

Cahoon, E B; Ripp, K G; Hall, S E; Kinney, A J

2001-01-26

Divergent forms of the plant Delta(12)-oleic-acid desaturase (FAD2) have previously been shown to catalyze the formation of acetylenic bonds, epoxy groups, and conjugated Delta(11),Delta(13)-double bonds by modification of an existing Delta(12)-double bond in C(18) fatty acids. Here, we report a class of FAD2-related enzymes that modifies a Delta(9)-double bond to produce the conjugated trans-Delta(8),trans-Delta(10)-double bonds found in calendic acid (18:3Delta(8trans,10trans,12cis)), the major component of the seed oil of Calendula officinalis. Using an expressed sequence tag approach, cDNAs for two closely related FAD2-like enzymes, designated CoFADX-1 and CoFADX-2, were identified from a C. officinalis developing seed cDNA library. The deduced amino acid sequences of these polypeptides share 40-50% identity with those of other FAD2 and FAD2-related enzymes. Expression of either CoFADX-1 or CoFADX-2 in somatic soybean embryos resulted in the production of calendic acid. In embryos expressing CoFADX-2, calendic acid accumulated to as high as 22% (w/w) of the total fatty acids. In addition, expression of CoFADX-1 and CoFADX-2 in Saccharomyces cerevisiae was accompanied by calendic acid accumulation when induced cells were supplied exogenous linoleic acid (18:2Delta(9cis,12cis)). These results are thus consistent with a route of calendic acid synthesis involving modification of the Delta(9)-double bond of linoleic acid. Regiospecificity for Delta(9)-double bonds is unprecedented among FAD2-related enzymes and further expands the functional diversity found in this family of enzymes.