RESUMO
Introduction: Cannabis sativa is a plant species with numerous active principles, so the list of its therapeutic uses is expanding. In this sense, there are numerous evidences of the possible medicinal use of terpenes, as well as their synergism with cannabinoids (entourage effect). Thus, as more countries contemplate the legalization and authorization of medical cannabis, the number of cannabis extraction and analysis laboratories is increasing to meet the demand, requiring adequate analytical tools. Methodology: In response to numerous inquiries from physicians, analytical laboratories and users, the PROBIEN chromatography laboratory has selected two methods for the analysis of terpenes in Cannabis oil by gas chromatography technique (GC-FID). The methods are described using HP-5 and Innowax columns. The external standard method was used for the quantitative determination of ß-Pinene, Myrcene, p-Cymene, Limonene, Linalool, α-Terpineol, Nerol and Geraniol. Results: good peak separation and reproducibility were observed, appropriate for the identification and quantification of the main terpenes in Cannabis extracts. The area/concentration ratio was linear in the range of 0.0005 to 2.0 mg/ml. Main conclusion: The described methods allow the identification and quantification of the major terpenes in Cannabis oil for an adequate quality control.
Introducción: Cannabis sativa es una especie vegetal con gran número de principios activos, por lo que la lista de sus usos terapéuticos se está ampliando. En este sentido, hay numerosas evidencias del posible uso medicinal de los terpenos, así como del sinergismo de ellos con los cannabinoides (efecto séquito). Así, a medida que más países contemplan la legalización y autorización del cannabis medicinal, el número de laboratorios de extracción y análisis de cannabis aumenta para satisfacer la demanda, requiriéndose herramientas analíticas adecuadas. Metodología: En respuesta a numerosas consultas de médicos, laboratorios de análisis y usuarios, el laboratorio de cromatografía del PROBIEN ha seleccionado dos métodos para el análisis de terpenos en aceite de Cannabis por la técnica de cromatografía gaseosa (GC-FID). Se describen los métodos usando las columnas HP-5 e Innowax. Se empleó el método del estándar externo para la determinación cuantitativa de ß-Pineno, Myrceno, p-Cymeno, Limoneno, Linalool, α-Terpineol, Nerol y Geraniol. Resultados: se observó una buena separación de picos y reproducibilidad, apropiadas para la identificación y cuantificación de los principales terpenos en extractos de Cannabis. La relación área/concentración fue lineal en el rango de 0,0005 a 2,0 mg/ml. Conclusión principal: los métodos descritos permiten la identificación y cuantificación de los terpenos mayoritarios en aceite de Cannabis para un control de calidad adecuado.
Assuntos
Canabinoides , Cannabis , Humanos , Terpenos/análise , Cannabis/química , Reprodutibilidade dos Testes , Cromatografia Gasosa-Espectrometria de Massas/métodos , Canabinoides/análise , Canabinoides/químicaRESUMO
Arsenic (As) is a toxic metalloid present in high levels in diverse regions of Argentina. The aim of this study was to determine acute As-mediated toxicity in two different populations of autochthonous Hyalella curvispina amphipods from a reference site (LB) and an agricultural one (FO) within North Patagonia Argentina. Previously, both populations exhibited significant differences in pesticide susceptibility. Lab assays were performed to determine acute lethal concentrations, as well as some biochemical parameters. Lethal concentration (LC50) values obtained after 48 and 96 hr As exposure were not significantly different between these populations, although FO amphipods appeared slightly less susceptible. LC50-48 hr values were 3.33 and 3.92 mg/L As, while LC50-96 hr values were 1.76 and 2.14 mg/L As for LB and FO amphipods. The no observed effect concentration (NOEC) values were 0.5 mg/L As. Cholinesterase (ChE) activity was significantly diminished by As acute exposure (0.5-1.5 mg/L As), indicative of a significant neurotoxic action for this metalloid in both amphipod populations. Activities of catalase (CAT) and glutathione S-transferase (GST) and levels of reduced glutathione (GSH) were differentially altered following As exposure. CAT activity was increased after 96 hr As exposure. GST activity and GSH levels were significantly elevated followed by either a decrease or a return to control values after 96 hr treatment. However, additional studies are necessary to understand the mechanisms underlying the As-mediated oxidative effects in H. curvispina. Our findings suggest that measurement of ChE activity in H. curvispina amphipods might serve as a useful biomarker of As exposure and effect.
Assuntos
Anfípodes/efeitos dos fármacos , Arsênio/toxicidade , Poluentes Químicos da Água/toxicidade , Irrigação Agrícola , Anfípodes/metabolismo , Animais , Antioxidantes/metabolismo , Argentina , Colinesterases/metabolismo , Glutationa/metabolismo , Lagos/química , Dose Letal MedianaRESUMO
BACKGROUND: The Pehuén or Monkey puzzle tree (Araucaria araucana) is an evergreen coniferous tree, which has been historically used for social, medicinal, and nutritional purposes. We have recently showed the value of A. araucana seeds as a rich source of micronutrients and antioxidants. This endemic species present in a reduced area in Argentina and Chile is endangered because of the low germination rate and the overexploitation of its edible seeds. Thus, the massive extraction of its seeds is ecologically non-viable resulting in limited availability of its active metabolites. However, biotechnological approaches are attractive strategies of production of valuable metabolites and healthy specimens of endangered plants. The aim of this work was to develop a protocol for in vitro production of antioxidants derived from A. araucana seeds and to obtain healthy plants by optimized seed germination. RESULTS: Calli of Pehuén seeds were induced in Murashige and Skoog medium with different combinations of auxins and cytokinins, in light and dark conditions. Callus from embryonic axes developed in medium with 1 mg/l α-naphthaleneacetic acid and 1.5 mg/l 6-benzylaminopurine in light conditions had efficient biomass production, antioxidant activity, high phenolic, and flavonoid content and no cytotoxicity on mammalian cells. Additionally, 100 % germination was obtained in vitro and healthy plants were acclimatized to non-sterile conditions. CONCLUSION: In conclusion, in vitro culture of A. araucana could provide new and sustainable options for production of its valuable metabolites with possible therapeutic and nutritional uses. Also, optimized plant germination and acclimatization of endangered species can contribute to the preservation of pristine environments.
RESUMO
In the last decade, green chemistry has been attracting great interest in many contexts, including, among others, natural antioxidants. However, only a few works deal with natural residue extracts and biowaste, which could be an efficient, economical and environmentally friendly source for the production of useful compounds. In this study, we look for antioxidant activity in Araucaria araucana seeds, an iconic pine species of the Argentine and Chilean Patagonia commonly known as "pehuén". Piñones are the edible pehuén seeds, and it is estimated that approximately 40 tons of piñones are harvested annually in Argentina and Chile. The chemical composition, antioxidants, metal corrosion-inhibiting properties and biological activity of edible and discarded piñón tissues were determined. Acute toxicity was discarded by in vitro testing and double fluorescent staining. Biological activity was evaluated in vivo by determining redox markers in salivary glands from rats treated with Cyclophosphamide (an oncological drug). All piñón tissues had antioxidants and antioxidant activity, with the coats showing the highest levels (up to 404 µg ascorbic acid equivalent per mg). The coats, in particular, had high gallic acid, catechin, quercetin and tannin contents, and more antioxidant activity, polyphenols and flavonoids than berries from the region. Results by X-ray fluorescence spectrometry showed that Na, Mg, P, S, Cl, K, and Ca were majority elements in the coat, embryo and endosperm. Furthermore, coat extract also showed significant anti-corrosion activity and in vivo protection against oxidative damage. The results indicate that piñón biowaste is a low-cost attractive source of natural antioxidants with potential nutraceutical, medical and metal corrosion protection applications.
Assuntos
Antioxidantes/farmacologia , Araucaria araucana/química , Produtos Biológicos/farmacologia , Suplementos Nutricionais , Substâncias Protetoras/farmacologia , Sementes/química , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Chlorocebus aethiops , Corrosão , Relação Dose-Resposta a Droga , Masculino , Estrutura Molecular , Picratos/antagonistas & inibidores , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Células VeroRESUMO
In Latin America, the high proportion of arsenic (As) in many groundwaters and phreatic aquifers is related to the volcanism of the Andean Range. Nevertheless, there is still very little published research on As and other elements occurrence, and/or transference to biota in Southern regions such as Argentinean Patagonia and the South Shetland Islands in Antarctica, where there are active volcanoes and geothermal processes. Therefore, this study was aimed to describe water quality from the main rivers of Argentinean Northern Patagonia through physicochemical analysis. The Patagonian and Antarctic biota (including samples of animal, plants, algae and bacteria) was characterized through the analysis of their As and other elemental concentrations (P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Se, Br, Rb and Sr), by synchrotron radiation x-ray fluorescence spectroscopy (SRXRF). Finally, the analysis of metal and As-proteins associations in As-accumulating organisms was performed by SRXRF after sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). A wide range of metal concentration including As (up to 950⯵g/L As) was found in water samples from Patagonian rivers. A hierarchical cluster analysis revealed that the elemental concentration of analysed biological samples was related to volcanic environments and their place in the trophic chain. Moreover, the results suggest that Se, Co, Cu, Br, and Cl are strong predictors of As in biota. On the other hand, As was not detected in proteins from the studied samples, suggesting biotransformation into soluble As-organic compounds. This is the first study to describe environmental pollution as a consequence of active volcanism, and its influence on water quality and elemental composition of biota in Argentinean Northern Patagonia and Antarctica.
Assuntos
Arsênio/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Oligoelementos/análise , Regiões Antárticas , Argentina , Erupções VulcânicasRESUMO
Arsenic (As) is a worldwide immunotoxic agent that is in contaminated waters and consumed by mammals. Phytotherapy may counteract its harmful effects. Lantana grisebachii Stuck (LG, Verbenaceae) and its extract are proposed as protective, given vvits in vitro bioactivity. The aim was to determine the protective capacity of the aqueous LG extract on splenocytes exposed in vivo to arsenic. Splenocytes were obtained from an arsenicosis model (Wistar rats consuming orally 0 [control; C] or 5 mg/Kg/d of As) that received 0-100 mg/Kg/d of LG extract for 30 days. As content (total reflection X-ray fluorescence), fatty acid profile (gas chromatography), γ-glutamyl transpeptidase activity (Szasz method), peroxides (xylenol orange-based assay), and nitrites (Griess reaction) were then assayed in viable splenocytes. Data were analyzed with ANOVA and the Tukey's test (p < .05). It was observed that the splenocytes contained 2.2 mg/Kg of this elemental arsenic. With γ-glutamyl transpeptidase inhibition and consequent triggering of hydroperoxides (p < .05), it was observed to increase saturated fatty acids and alter lipid profiles. LG treatment avoided damaging effects with values similar to unexposed C (p < .05), and cellular arsenic concentration (p < .0001). In conclusion, the aqueous extract of L. grisebachii counteracted arsenic toxicity in rat splenocytes by preventing its cellular accumulation and induction of lipid and redox disturbances, which may impair immune function.
Assuntos
Arsênio/toxicidade , Lantana/química , Extratos Vegetais/administração & dosagem , Baço/efeitos dos fármacos , Animais , Ácidos Graxos/análise , Peróxido de Hidrogênio/análise , Sistema Imunitário/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Nitritos/análise , Oxirredução , Fitoterapia , Ratos , Ratos Wistar , Baço/química , Baço/metabolismo , Água , gama-GlutamiltransferaseRESUMO
Arsenic (As) is used in the treatment of leukemia and breast cancer due to its oxidative cytotoxic action. However, it is also toxic to normal cells. One proposed anticancer mechanism induced by As might be nitrosative stress (NS). It is believed that antioxidant flavonoids in combination with As might reduce its toxic action on normal cells without interfering with its antitumor action. In the present study, we evaluated the antineoplastic potential of As on breast human cancer lines MCF-7 and ZR-75-1 treated with redox-modulating flavonoids, such as quercetin (Q) and silymarin (S). Even though both cell lines differed about their oxidative responsiveness, their viability was decreased by NS induction through γ-glutamyltranspeptidase inhibition. Arsenic triggered NS in both MCF-7 and ZR-75-1 cultures, with the formers more sensitive without recovering their pre-treatment capacity. ZR-75-1 cells maintained their antioxidant status, whereas MCF-7 ones treated with S, As, and As + Q did not. Silymarin did not interfere with the described As bioactivity. NS was an anticancer mechanism exerted by As depending on the redox cellular response that could be differentially modified by dietary antioxidants. Hence, it is worthwhile to consider the use of dietary antioxidants as adjuvant in cancer chemotherapy, especially when using As.
Assuntos
Antioxidantes/farmacologia , Arsenitos/farmacologia , Neoplasias da Mama/patologia , Estresse Oxidativo/efeitos dos fármacos , Quercetina/farmacologia , Silimarina/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Nitrosação , Oxirredução/efeitos dos fármacos , gama-Glutamiltransferase/antagonistas & inibidores , gama-Glutamiltransferase/metabolismoRESUMO
Phytochemicals have been presumed to possess prophylactic and curative properties in several pathologies, such as arsenic- (As-) induced immunosuppression. Our aim was to discover a lymphoprotective extract from Lantana grisebachii Stuck. (Verbenaceae) (LG). We assessed its bioactivity and chemical composition using cell-based assays. Fractions produced from a hexane extract acutely induced nitrite formation in T-activated cell cultures (P < 0.0001). Water extraction released a fraction lacking nitrite inducing activity in both lymphocyte types. Aqueous LG was found to be safe in proliferated and proliferating cells. The infusion-derived extract presented better antioxidant capacity in proportion to phenolic amount in lymphocytes (infusive LG-1i at 100 µ g/mL), which protected them against in vitro As-induced lymphotoxicity (P < 0.0001). This infusive LG phytoextract contained 10.23 ± 0.43 mg/g of phenolics, with 58.46% being flavonoids. Among the phenolics, the only predominant compound was 0.723 mg of chlorogenic acid per gram of dry plant, in addition to 10 unknown minor compounds. A fatty acid profile was assessed. It contained one-third of saturated fatty acids, one-third of ω 9, followed by ω 6 (~24%) and ω 3 (~4%), and scarce ω 7. Summing up, L. grisebachii was a source of bioactive and lymphoprotective compounds, which could counteract As-toxicity. This supports its phytomedical use and research in order to reduce As-related dysfunctions.
RESUMO
Several pathologies (e.g. cancer and diabetes) are increased in arsenic-exposed populations, with oxidative stress being a major toxicological mechanism. Since the flavonoids silymarin (S) and quercetin (Q) are antioxidants and may protect cells, it would be valuable to develop a model which allows assessing the potential of xenobiotic against arsenic cytotoxicity in an efficient and rapid way. Thus, the oxidant production [e.g. reactive oxygen species and reactive nitrogen species (RNS)], the molecular parameters of biological response [e.g. plasma membrane composition, actin microfilaments and activated diphosphorilated c-Jun N-terminal kinase (JNK)] and cellular viability were determined in CHO-K1 cells treated with arsenite (As), S and Q. Arsenic caused loss of the cellular viability in a time-dependent manner. This effect was accompanied by a lipid hydroperoxide (LHP) formation, with no RNS induction or ganglioside content changes being found. Both flavonoids counteracted oxidative damage. Despite all treatments had unspecific responses on nitrite cellular release along the time, there was no relation between them and the cellular viability. Arsenic induced cytoplasmic microfilament rearrangement (tight perinuclear distribution with projections, stress fibres and pseudopodia) which was reversed by S. Also, activated JNK showed a similar distribution to actin. Contrarily, Q caused a dysmorphic granular pattern, thus behaving as a toxic agent. Summing up, toxic levels of arsenic disturb the redox homeostasis with LHP induction and early triggering of stress responses in cytoskeleton and cell signalling. Using the proposed model, only S showed to protect cells from arsenical cytotoxicity without own toxic properties. Thus, S might be considered for modulation of the human arsenic susceptibility.
Assuntos
Antioxidantes/farmacologia , Intoxicação por Arsênico/metabolismo , Arsenitos/toxicidade , Biomarcadores , Quercetina/farmacologia , Silimarina/farmacologia , Animais , Células CHO , Sobrevivência Celular , Células Cultivadas , Cricetinae , Cricetulus , Citoplasma/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Peróxidos Lipídicos/metabolismo , Oxirredução , Estresse OxidativoRESUMO
AIMS: To establish the differential cytoprotective activity against arsenic (As) toxicity of the flavonoids silymarin (S), which is without protective effects on cancer cells, and quercetin (Q). Arsenic (As) has a paradoxical biomedical role: it causes oxidative damage to normal cells leading to death or malignant transformation, but can be used, for the same reason, as an anticancer pro-apoptotic agent at high doses. MAIN METHODS: Aqueous hydroperoxides (AHP), JNK (c-Jun N-terminal kinase) activation, caspase activity and death phenotype were assessed in CHO-K1 cells treated with As, S, Q, As+S and As+Q (p<0.05). KEY FINDINGS: Q proved to be toxic and did not exert complete protection against As, and only S was able to protect cells from As-induced oxidative death, which started after 4h with caspase activation and phosphatidylserine exteriorization on the outer cellular membrane. Although both flavonoids counteracted As-induced JNK activation (an early stress response, i.e. exposure biomarker), AHP were increased by As and Q (p<0.05). Moreover, Q-treated cells triggered per se apoptosis and even necrosis. Also, the classical sequence oxidative stress-JNK activation-cell death was seen for As, but not for Q, with S stopping the sequence. SIGNIFICANCE: These results strongly suggest that the use of silymarin increases the possibility of designing better arsenic-based cancer chemotherapies with less toxicity to normal cells.
Assuntos
Apoptose/efeitos dos fármacos , Arsenitos/farmacologia , Citoproteção/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Quercetina/farmacologia , Silimarina/farmacologia , Compostos de Sódio/farmacologia , Animais , Arsenitos/toxicidade , Células CHO , Caspases/metabolismo , Cricetinae , Cricetulus , Células Epiteliais/patologia , Citometria de Fluxo , Peróxido de Hidrogênio/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Microscopia de Fluorescência , Estresse Oxidativo/efeitos dos fármacos , Compostos de Sódio/toxicidadeRESUMO
Arsenic (As) is one of the most abundant hazards in the environment and it is a human carcinogen. Related to excretory functions, the kidneys in humans, animal models or naturally exposed fauna, are target organs for As accumulation and deleterious effects. Previous studies carried out using X-ray fluorescence spectrometry by synchrotron radiation (SR-microXRF) showed a high concentration of As in the renal cortex of chronically exposed rats, suggesting that this is a suitable model for studies on renal As accumulation. This accumulation was accompanied by a significant increase in copper (Cu) concentration. The present study focused on the localization of these elements in the renal cortex and their correlation with physiological and histological As-related renal effects. Experiments were performed on nine male Wistar rats, divided into three experimental groups. Two groups received 100 microg/ml sodium arsenite in drinking water for 60 and 120 consecutive days, respectively. The control group received water without sodium arsenite (< 50 ppb As). For histological analysis, 5-mum-thick sections of kidneys were stained with hematoxylin and eosin. Biochemical analyses were used to determine concentrations of plasma urea and creatinine. The As and Cu mapping were carried out by SR-microXRF using a collimated white synchrotron spectrum (300 microm x 300 microm) on kidney slices (2 mm thick) showing As and Cu co-distribution in the renal cortex. Then, renal cortical slices (100 microm thick) were scanned with a focused white synchrotron spectrum (30 microm x 30 microm). Peri-glomerular accumulation of As and Cu at 60 and 120 days was found. The effects of 60 days of arsenic consumption were seen in a decreased Bowman's space as well as a decreased plasma blood urea nitrogen (BUN)/creatinine ratio. Major deleterious effects; however, were seen on tubules at 120 days of exposition. This study supports the hypothesis that tubular accumulation of As-Cu may have some bearing on the arsenic-associated nephrotoxicological process.
Assuntos
Arsênio/metabolismo , Arsenitos/metabolismo , Cobre/metabolismo , Poluentes Ambientais/metabolismo , Córtex Renal/metabolismo , Compostos de Sódio/metabolismo , Animais , Arsênio/toxicidade , Arsenitos/toxicidade , Nitrogênio da Ureia Sanguínea , Cobre/toxicidade , Creatina/sangue , Poluentes Ambientais/toxicidade , Córtex Renal/efeitos dos fármacos , Córtex Renal/patologia , Masculino , Ratos , Ratos Wistar , Compostos de Sódio/toxicidade , Testes de Toxicidade Crônica , Ureia/sangueRESUMO
Arsenic has been proposed as a chemotherapeutic agent for leukemia and other solid tumors. However, its environmental exposure has been linked epidemiologically with an elevated carcinoma risk (i.e. skin, bladder and lung), with cellular oxidative stress being implicated in both induced-arsenic toxicity and carcinogenicity. Consequently, antioxidants may differentially interfere in these effects. The human mammary adenocarcinoma lines MCF-7 and ZR-75-1 were treated in vitro with 200 microM NaAsO(2) (As), 5 microM silymarin (S) and/or 50 microM quercetin (Q). The following biomembrane parameters were assessed: sialic acid (SA) in gangliosides, gamma-glutamyltranspeptidase activity (GGT), conjugated dienes and free radical activity, in order to evaluate the arsenite-flavonoid interactions. The time-dependent arsenite toxicity was not prevented by flavonoids in ZR-75-1 cells, whereas quercetin protected MCF-7 cells for 8 h. With regard to GGT, only quercetin protected ZR-75-1 cells against stress. In MCF-7 cells, the arsenite-induced GGT activity was not counteracted by either quercetin or silymarin. S, Q, As and As + S treatments reduced the SA content only in the MCF-7 membrane, while As + Q treatment increased it in both lines. The membrane resistance to lipid oxidation in these cells enclosed the up-regulation of GGT activity and sialylglycolipid content. Taking these results together, quercetin interfered with arsenite toxicity, whereas silymarin was not able. Thus, the potential role of flavonoids as co-adjutants may differ widely in therapeutic protocols.
Assuntos
Arsenitos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Quercetina/farmacologia , Silimarina/farmacologia , Compostos de Sódio/toxicidade , Neoplasias da Mama , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Feminino , Radicais Livres/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Ácido N-Acetilneuramínico/metabolismo , Fatores de Tempo , gama-Glutamiltransferase/metabolismoRESUMO
Rigid plaques containing protein particles in plasma membrane build on the apical surface of the mammalian urothelium. We have previously shown that dietary fats modified the fatty acid profile as well as the fluorescence anisotropy of rat urothelial plasma membranes. In this study, we have further examined the proportion of phosphatidylcholine, phosphatidylethanolamine, cerebrosides, sulfatides and cholesterol in detergent resistant (DRM) and soluble (DSM) plasma membrane fractions as well as the properties of the particles. Four groups of weaned rats were fed for 12 weeks on a commercial diet (control), or on a formula containing 5% (w/w) of corn oil, fish oil or olein. The control DRM behaved as a distinctive domain since it was enriched in cholesterol and glycosphingolipids. DSM showed higher levels of phosphatidylcholine and phosphatidylethanolamine with respect to DRM. On the other hand, the lipid distributions were affected by the diets. Homogeneous lipid distributions between DSM and DRM were found in olein membranes, suggesting a decreased potential formation of lipid domains. In addition, properties of the uroplakins were altered by dietary treatments. Thus, uroplakins (UP) Ia, Ib, II and III observed by SDS-PAGE, were in lower proportions (mainly olein) than in controls. Moreover, a higher proportion of UPIII was cross-linked to UPIII and UPlb in olein treatment than in control. Meanwhile, only cross-linking to UPIII or UPIb was altered in corn and fish diets, respectively. These results suggest a role of the lipids in the establishment of the uroplakin interactions. Thus, specific dietary fats may have important functional implications.