Salivary gland metabolism in an animal model of chronic kidney disease.

OBJECTIVE: The aim of this study was to determine the effects of experimental CKD into the metabolism of parotid and submandibular glands of rats. CKD was induced by 5/6 nephrectomy. DESIGN: Serum analyses of BUN (Blood Urea Nitrogen) and creatinine concentrations were performed. Major salivary glands metabolism was investigated in vivo, both at rest and during salivary stimulation conditions by NMR isotopomer analysis, using [U-13C]glucose as metabolic tracer. RESULTS: CKD increases BUN and serum creatinine concentrations (p < 0.001). Multiple metabolic alterations were detected in the parotid glands of this animal model, including decreased concentrations of alanine (p < 0.05) and creatine (p < 0.05) and increased lactate/alanine ratios (p < 0.05). The salivary stimulus fostered accumulations of acetate at both analyzed glands of the CKD model (p < 0.05), indicative of disruption of the oxidative metabolic process. CONCLUSIONS: Experimental CKD induced by 5/6 nephrectomy altered the parotid salivary gland function, since glucose metabolism is clearly affected after stimulation for salivation in this gland.

Biodegradable antioxidant chitosan films useful as an anti-aging skin mask.

Cosmetics, personal care and biomedical products obtained by bio-based polymers and natural bioactive compounds are a new growing market. The ecological awareness is changing consumers' demands, causing consumers to look for more sustainable options, with a reduced environmental impact. The innovation of this work was to develop a natural polymer matrix (chitosan) entrapping antioxidant actives compounds such as annatto (Bixa Orellana L.) and vitamin C with potential application as sustainable anti-aging skin mask treatment. Films of chitosan (Ch) and reacetylated chitosan (RCh), exhibiting different degrees of acetylation (DA = 13.3 and 33.9%, respectively), were produced. The formulations of active films of chitosan (BCh) and reacetylated chitosan (BRCh) were 1% (w/w) of chitosan, 1% (w/w) of annatto powder, 5% (w/w) of vitamin C and 1% (w/w) of glycerol (as plasticizer). Reacetylated chitosan films (DA = 33.9%) presented higher water affinity than chitosan films (DA = 13.3%). The elongation of RCh and BRCh increased and the resistance decreased, as compared to Ch and BCh. The antioxidants compounds (annatto and vitamin C) of BRCh films released faster than BCh films. Thus, the BRCh films showed potential application as an anti-aging skin mask.

Posterior urethral valves: comparison of clinical outcomes between postnatal and antenatal cohorts.

BACKGROUND: Posterior urethral valves (PUVs) constitute the most common infravesical urinary obstruction in boys and are often accompanied by severe consequences to the lower and upper urinary tract. Currently, about two-thirds of diagnosis of PUVs has been suspected by prenatal ultrasonography findings. The aim of this study was to compare long-term clinical outcomes in two groups of patients with PUVs, with antenatal vs. postnatal diagnosis. STUDY DESIGN: This was a retrospective cohort study of 173 patients with PUVs systematically followed up in a tertiary center. Median follow-up time was 66.5 months (interquartile range [IQ], 11.4-147.9 months) for those patients who survived neonatal period. Seventy-nine (45.6%) patients were followed up for more than 5 years and 55 (32%) for more than 10 years. For analysis, the cohort was stratified into two groups according to the clinical presentation (prenatal vs. postnatal). The events of interest were urinary tract infection (UTI), surgical interventions, proteinuria, hypertension, chronic kidney disease (CKD), and death. Survival analyses were performed to evaluate time until occurrence of the events. RESULTS: Sixty-two patients (35.8%) were diagnosed by fetal sonography. Patients of postnatal group presented a higher incidence rate of UTI episodes (6.5, 95% confidence interval [CI], 4.9-8.3) than antenatal group (1.2, 95% CI, 0.4-2.7) (P < 0.001). Thirty-six patients (21%) presented hypertension, and 77 (44.5%) had persistent mild proteinuria. There was no significant difference in the estimated incidence of hypertension (P = 0.28) and proteinuria (P = 0.78) between antenatal and postnatal groups. The cumulative incidence of CKD stage ≥3 was estimated to be about 37% at 10 years of age, and 56% at 18 years of age. By survival analysis, there was no significant difference in the estimated incidence of CKD stage ≥3 (log-rank = 0.32, P = 0.57) and CKD stage 5 (log-rank = 1.08, P = 0.28, Figure) between antenatal and postnatal groups. Of 173 patients included in the analysis, 13 (7.5%) died during follow-up with a median age of 2.6 months (IQ, 15 days-62 months). Survival analyses have not shown any significant difference in the estimated incidence of death between antenatal and postnatal groups (log-rank = 1.38, P = 0.24). CONCLUSION: The study findings did not corroborate the initial hypothesis that the rates of renal function declining in patients with PUVs would be attenuated by an early diagnosis and intervention after antenatal diagnosis.

Molecular Dynamics of Cyclodextrins in Water Solutions from NMR Deuterium Relaxation: Implications for Cyclodextrin Aggregation.

The aggregation of the most common natural cyclodextrins (α-, ß-, and γ-) in aqueous solutions is addressed by studying the CD-CD interactions using deuterium relaxation rates for deuterium labeled CDs. Relaxation times (T1) and their corresponding relaxation rates (R1 = 1/T1) provide information about the rotational correlation times of CDs and serve as a proxy for solute-solute interactions. Measured T1's for α-, ß-, and γ-CD at the lowest CD concentrations were in agreement with predictions of a hydrodynamic model for toroids, in particular with regard to the dependence of T1 on CD size. On the other hand, the dependence of T1's with respect to the increase in CD concentration could not be explained by hydrodynamic or direct interaction between CD molecules, and it is suggested that there is an equilibrium between monomeric and dimeric CD to account for the observed concentration dependence. No evidence in favor of large aggregates of CDs involving a non-negligible fraction was found for the investigated CDs.

Naphthoquinoxaline metabolite of mitoxantrone is less cardiotoxic than the parent compound and it can be a more cardiosafe drug in anticancer therapy.

Mitoxantrone (MTX) is an antineoplastic agent used to treat several types of cancers and on multiple sclerosis, which shows a high incidence of cardiotoxicity. Still, the underlying mechanisms of MTX cardiotoxicity are poorly understood and the potential toxicity of its metabolites scarcely investigated. Therefore, this work aimed to synthesize the MTX-naphthoquinoxaline metabolite (NAPHT) and to compare its cytotoxicity to the parent compound in 7-day differentiated H9c2 cells using pharmacological relevant concentrations (0.01-5 µM). MTX was more toxic in equivalent concentrations in all cytotoxicity tests performed [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide reduction, neutral red uptake, and lactate dehydrogenase release assays] and times tested (24 and 48 h). Both MTX and NAPHT significantly decreased mitochondrial membrane potential in 7-day differentiated H9c2 cells after a 12-h incubation. However, energetic pathways were affected in a different manner after MTX or NAPHT incubation. ATP increased and lactate levels decreased after a 24-h incubation with MTX, whereas for the same incubation time and concentrations, NAPHT did not cause any significant effect. The increased activity of ATP synthase seems responsible for MTX-induced increases in ATP levels, as oligomycin (an inhibitor of ATP synthase) abrogated this effect on 5 µM MTX-incubated cells. 3-Methyladenine (an autophagy inhibitor) was the only molecule to give a partial protection against the cytotoxicity produced by MTX or NAPHT. To the best of our knowledge, this was the first broad study on NAPHT cardiotoxicity, and it revealed that the parent drug, MTX, caused a higher disruption in the energetic pathways in a cardiac model in vitro, whereas autophagy is involved in the toxicity of both compounds. In conclusion, NAPHT is claimed to largely contribute to MTX-anticancer properties; therefore, this metabolite should be regarded as a good option for a safer anticancer therapy since it is less cardiotoxic than MTX.

Ghrelin acts as energy status sensor of male reproduction by modulating Sertoli cells glycolytic metabolism and mitochondrial bioenergetics.

Ghrelin is a growth hormone-releasing peptide that has been suggested to interfere with spermatogenesis, though the underling mechanisms remain unknown. We studied the effect of ghrelin in human Sertoli cells (hSCs) metabolic phenotype. For that, hSCs were exposed to increasing concentrations of ghrelin (20, 100 and 500 pM) mimicking the levels reported in obese, normal weight, and severely undernourished individuals. The metabolite production/consumption was determined. The protein levels of key glycolysis-related transporters and enzymes were assessed. The lactate dehydrogenase (LDH) activity was measured. Mitochondrial complexes protein levels and mitochondria membrane potential were also measured. We showed that hSCs express the growth hormone secretagogue receptor. At the concentration present in the plasma of normal weight men, ghrelin caused a decrease of glucose consumption and mitochondrial membrane potential in hSCs, though LDH activity and lactate production remained unchanged, illustrating an alteration of glycolytic flux efficiency. Exposure of hSCs to levels of ghrelin found in the plasma of severely undernourished individuals decreased pyruvate consumption and mitochondrial complex III protein expression. All concentrations of ghrelin decreased alanine and acetate production by hSCs. Notably, the effects of ghrelin levels found in severely undernourished individuals were more pronounced in hSCs metabolic phenotype highlighting the importance of a proper eating behavior to maintain male reproductive potential. In conclusion, ghrelin acts as an energy status sensor for hSCs in a dose-dependent manner, showing an inverse association with the production of lactate, thus controlling the nutritional support of spermatogenesis.

Lecithin, gelatin and hydrolyzed collagen orally disintegrating films: functional properties.

Orally disintegrating films (ODFs) can transport natural active compounds such as ethanol extract of propolis (EEP). This paper aimed to investigate the effect of lecithin on different gelatin and hydrolyzed collagen (HC) polymeric matrices with addition of EEP. ODFs were prepared by casting technique and were characterized (color parameters, water content, mechanical properties, microstructure, disintegration time (DT), infrared spectroscopy (FTIR), contact angle (CA), swelling degree and total phenolic content). The mechanical properties were influenced by HC. The microstructure demonstrated increased porosity and roughness in films with EEP, and the addition of lecithin resulted in an increase in the number of pores. Lecithin-gelatin and lecithin-EEP-gelatin interactions were observed by FTIR. The addition of HC and EEP reduced the DT and CA, and HC and lecithin reduced the swelling capacity. However, the swelling capacity was not affected by presence of EEP. The addition of lecithin to gelatin and HC ODFs may improve the incorporation and the oral transport of active compounds such as EEP.

High sucrose consumption induces memory impairment in rats associated with electrophysiological modifications but not with metabolic changes in the hippocampus.

High sugar consumption is a risk factor for metabolic disturbances leading to memory impairment. Thus, rats subject to high sucrose intake (HSu) develop a metabolic syndrome and display memory deficits. We now investigated if these HSu-induced memory deficits were associated with metabolic and electrophysiological alterations in the hippocampus. Male Wistar rats were submitted for 9 weeks to a sucrose-rich diet (35% sucrose solution) and subsequently to a battery of behavioral tests; after sacrifice, their hippocampi were collected for ex vivo high-resolution magic angle spinning (HRMAS) metabolic characterization and electrophysiological extracellular recordings in slices. HSu rats displayed a decreased memory performance (object displacement and novel object recognition tasks) and helpless behavior (forced swimming test), without altered locomotion (open field). HRMAS analysis indicated a similar hippocampal metabolic profile of HSu and control rats. HSu rats also displayed no change of synaptic transmission and plasticity (long-term potentiation) in hippocampal Schaffer fibers-CA1 pyramid synapses, but had decreased amplitude of long-term depression in the temporoammonic (TA) pathway. Furthermore, HSu rats had an increased density of inhibitory adenosine A1 receptors (A1R), that translated into a greater potency of A1R in Schaffer fiber synapses, but not in the TA pathway, whereas the endogenous activation of A1R in HSu rats was preserved in the TA pathway but abolished in Schaffer fiber synapses. These results suggest that HSu triggers a hippocampal-dependent memory impairment that is not associated with altered hippocampal metabolism but is probably related to modified synaptic plasticity in hippocampal TA synapses.

Development and reproduction of Spodoptera eridania (Lepidoptera: Noctuidae) and its egg parasitoid Telenomus remus (Hymenoptera: Platygastridae) on the genetically modified soybean (Bt) MON 87701×MON 89788.

Genetically modified crops with insect resistance genes from Bacillus thuringiensis Berliner (Bt-plants) are increasingly being cultivated worldwide. Therefore, it is critical to improve our knowledge of their direct or indirect impact not only on target pests but also on non-target arthropods. Hence, this study evaluates comparative leaf consumption and performance of Spodoptera eridania (Cramer), a species that is tolerant of the Cry1Ac protein, fed with Bt soybean, MON 87701×MON 89788 or its near [corrected] non-Bt isoline. Using this species as a model, we assessed [corrected] the comparative performance of the egg parasitoid Telenomus remus Nixon on eggs of S. eridania produced from individuals that fed on these two soybean genotypes [corrected] as larvae. Results showed that Bt soybean did not affect pest foliage consumption, but did reduce larvel duration by two days despite larvae in both treatments having six instars. Nevertheless, survival of S. eridania larvae, pupal weight, sex ratio, fecundity and longevity of female moths, and egg viability did not differ between Bt and non-Bt soybeans. Adult longevity of S. eridania males was increased when caterpillars were fed with Bt soybean versus the near isoline. No adverse effects of this technology were observed for the egg parasitoid T. remus. [corrected].

Mitochondrial metabolism directs stemness and differentiation in P19 embryonal carcinoma stem cells.

The relationship between mitochondrial metabolism and cell viability and differentiation in stem cells (SCs) remains poorly understood. In the present study, we compared mitochondrial physiology and metabolism between P19SCs before/after differentiation and present a unique fingerprint of the association between mitochondrial activity, cell differentiation and stemness. In comparison with their differentiated counterparts, pluripotency of P19SCs was correlated with a strong glycolytic profile and decreased mitochondrial biogenesis and complexity: round, low-polarized and inactive mitochondria with a closed permeability transition pore. This decreased mitochondrial capacity increased their resistance against dichloroacetate. Thus, stimulation of mitochondrial function by growing P19SCs in glutamine/pyruvate-containing medium reduced their glycolytic phenotype, induced loss of pluripotent potential, compromised differentiation and became P19SCs sensitive to dichloroacetate. Because of the central role of this type of SCs in teratocarcinoma development, our findings highlight the importance of mitochondrial metabolism in stemness, proliferation, differentiation and chemoresistance. In addition, the present work suggests the regulation of mitochondrial metabolism as a tool for inducing cell differentiation in stem line therapies.

Biochemical and metabolic effects of a short-term exposure to nanoparticles of titanium silicate in tadpoles of Pelophylax perezi (Seoane).

This study aimed to evaluate sublethal effects of a short-term exposure (96 h) to titanium silicate nanoparticles (TiSiO(4)-NP) on Pelophylax perezi tadpoles. Tadpoles were exposed to five concentrations of TiSiO(4)-NP (8.2, 10.2, 12.8, 16 and 20 mg/L) plus a control. Effect criteria were: mortality, cholinesterases, glutathione S-transferases, lactate dehydrogenase, and catalase activities, and alanine and lactate contents. Light scattering was used for physical characterization of TiSiO(4)-NP suspensions, revealing a high aggregation state of the NP, consistent with low z-potential values (<30 mV). Mortality among TiSiO(4)-NP treatments was <11%. Significant differences relatively to the control were observed at the biochemical level (for CAT and LDH) and in lactate and alanine contents, which may end-up in increased oxidative stress. Overall, some of the monitored endpoints suggest metabolic alterations in TiSiO(4)-NP exposed tadpoles, highlighting the potential of TiSiO(4)-NP long-term effects on these organisms.

Experimental (IR/Raman and 1H/13C NMR) and theoretical (DFT) studies of the preferential conformations adopted by L-lactic acid oligomers and poly(L-lactic acid) homopolymer.

L-Lactic acid (L-LA) oligomers (up to the pentamer) were studied by three complementary approaches: vibrational (IR and Raman) and NMR ((1)H and (13)C) spectroscopies and DFT calculations. Vibrational and NMR spectra of L-LA oligomers and poly(L-lactic acid) (PLLA) homopolymer were recorded at room temperature and interpreted. Further insight into the structures (conformations) of the title systems was provided by theoretical B3LYP/6-311++G(d,p) studies. Calculated energies and computed vibrational and NMR spectra of the most stable conformers of L-LA oligomers, together with the experimental vibrational and NMR spectra, enabled the characterization of the preferred conformations adopted by PLLA chains.

Effect of insulin deprivation on metabolism and metabolism-associated gene transcript levels of in vitro cultured human Sertoli cells.

BACKGROUND: Sertoli cells metabolize glucose producing lactate for developing germ cells. As insulin regulates glucose uptake and its disturbance/insensitivity is associated with diabetes mellitus, we aimed to determine the effect of insulin deprivation in human Sertoli cell (hSC) metabolism and metabolism-associated gene expression. METHODS: hSC-enriched primary cultures were maintained in the absence/presence of insulin and metabolite variations were determined by (1)H-NMR. mRNA expression levels of glucose transporters (GLUT1, GLUT3), lactate dehydrogenase (LDHA) and monocarboxylate transporter (MCT4) were determined by RT-PCR. RESULTS: Insulin deprivation resulted in decreased lactate production and in decrease of glucose consumption that was completely reverted after 6h. Cells of both groups consumed similar amounts of glucose. In insulin-deprived cells, transcript levels of genes associated to lactate metabolism (LDHA and MCT4) were decreased. Transcript levels of genes involved in glucose uptake exhibited a divergent variation: GLUT3 levels were decreased while GLUT1 levels increased. Insulin-deprived hSCs presented: 1) altered glucose consumption and lactate secretion; 2) altered expression of metabolism-associated genes involved in lactate production and export; 3) an adaptation of glucose uptake by modulating the expression of GLUT1 and GLUT3. GENERAL SIGNIFICANCE: This is the first report regarding the effect of insulin-deprivation on hSC metabolism.

Overexpression of a cytochrome P450 monooxygenase, CYP6ER1, is associated with resistance to imidacloprid in the brown planthopper, Nilaparvata lugens.

The brown planthopper, Nilaparvata lugens, is an economically significant pest of rice throughout Asia and has evolved resistance to many insecticides including the neonicotinoid imidacloprid. The resistance of field populations of N. lugens to imidacloprid has been attributed to enhanced detoxification by cytochrome P450 monooxygenases (P450s), although, to date, the causative P450(s) has (have) not been identified. In the present study, biochemical assays using the model substrate 7-ethoxycoumarin showed enhanced P450 activity in several resistant N. lugens field strains when compared with a susceptible reference strain. Thirty three cDNA sequences encoding tentative unique P450s were identified from two recent sequencing projects and by degenerate PCR. The mRNA expression level of 32 of these was examined in susceptible, moderately resistant and highly resistant N. lugens strains using quantitative real-time PCR. A single P450 gene (CYP6ER1) was highly overexpressed in all resistant strains (up to 40-fold) and the level of expression observed in the different N. lugens strains was significantly correlated with the resistance phenotype. These results provide strong evidence for a role of CYP6ER1 in the resistance of N. lugens to imidacloprid.

Influence of 5α-dihydrotestosterone and 17ß-estradiol on human Sertoli cells metabolism.

Sertoli cells metabolize glucose, converting it to lactate that is used by developing germ cells for their energy metabolism. Androgens and oestrogens have metabolic roles that reach far beyond reproductive processes. So, the main purpose of this study was to examine the effect of sex steroid hormones on metabolite secretion/consumption in human Sertoli cells. Human Sertoli cell-enriched primary cultures were maintained in a defined medium for 50 h and glucose, pyruvate, lactate and alanine variations were determined using (1) H-NMR spectra analysis, in the absence or presence of 100 nm 17ß-estradiol (E(2) ) or 100 nm 5α-dihydrotestosterone (DHT). The mRNA expression levels of glucose transporters, lactate dehydrogenase and monocarboxylate transporters were also determined using semi-quantitative RT-PCR. Cells cultured in the absence (control) or presence of E(2) consumed the same amounts of glucose at similar rates during the 50 h. During the first 15 h of treatment with DHT, glucose consumption and glucose consumption rate were significantly higher. Nevertheless, DHT-treated cells secreted a significantly lower amount of lactate than control and E(2) -treated cells. Such a decrease was concomitant with a significant decrease in lactate dehydrogenase A mRNA levels after 50 h treatment in DHT-treated groups. Finally, alanine production was significantly increased in E(2) -treated cells after 25 h treatment, which indicated a lower redox/higher oxidative state for the cells on those conditions. These results support the existence of a relationship between sex steroid hormones action and energy metabolism, providing the first assessment of androgens and oestrogens as metabolic modulators of human Sertoli cells.

DNA fragmentation in canine oocytes after in vitro maturation in TCM-199 medium supplemented with different proteins.

In the present study, the effect of different protein supplementation on meiotic nuclear configuration, DNA fragmentation (TUNEL assay) and metabolic parameters of dog oocytes cultured in vitro for 72 h was investigated. TCM-199 medium was supplemented either with 0.3% bovine serum albumin (BSA) or with 10% bitch heat inactivated plasma (OBP) collected before the LH peak or with OBP collected between the LH peak and ovulation or OBP collected after ovulation. After culture, more than 70% of the cumulus-oocyte complexes cultured in plasma groups presented extensive cell expansion, while none of those cultured in BSA showed extensive expansion of the cumulus (P < 0.05). Glucose consumption and lactate production was lower (P < 0.05) in the BSA-supplemented medium than in plasma-supplemented groups. In all groups, high amounts of alanine were produced. A higher number of oocytes with DNA fragmentation were observed in the BSA group, while in the plasma-supplemented groups more oocytes presented undistinguishable nuclear material. Only a small percentage of the oocytes (7.4-12.7%) had intact DNA after culture and within these, no differences were observed between groups in number of oocytes at each chromatin configuration stage. No differences in the percentage of oocytes reaching metaphase II (MII) were observed between experimental groups. Still, only 2% of cultured oocytes reached MII, but 85.7% of these had intact DNA. Conversely, all other chromatin configurations presented a high proportion of fragmented DNA (germinal vesicle 79.8%; meiosis resumption 73.3%; unclassified 95.2%). In conclusion, a high percentage of canine oocytes that do not complete meiotic maturation to MII are degenerated, whereas a high proportion of MII oocytes have intact DNA, independently of the protein supplement used.

Contribution of catecholamine reactive intermediates and oxidative stress to the pathologic features of heart diseases.

Pathologic heart conditions, particularly heart failure (HF) and ischemia-reperfusion (I/R) injury, are characterized by sustained elevation of plasma and interstitial catecholamine levels, as well as by the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). Despite the continuous and extensive research on catecholamines since the early years of the XX(th) century, the mechanisms underlying catecholamine-induced cardiotoxicity are still not fully elucidated. The role of catecholamines in HF, stress cardiomyopathy, I/R injury, ageing, stress, and pheochromocytoma will be thoroughly discussed. Furthermore and although the noxious effects resulting from catecholamine excess have traditionally been linked to adrenoceptors, in fact, several evidences indicate that oxidative stress and the oxidation of catecholamines can have important roles in catecholamine-induced cardiotoxicity. Accordingly, the reactive intermediates formed during catecholamine oxidation have been associated with cardiac toxicity, both in in vitro and in vivo studies. An insight into the influence of ROS, RNS, and catecholamine oxidation products on several heart diseases and their clinical course will be provided. In addition, the source and type of oxidant species formed in some heart pathologies will be referred. In this review a special focus will be given to the research of cardiac pathologies where catecholamines and oxidative stress are involved. An integrated vision of these matters is required and will be provided along this review, namely how the concomitant surge of catecholamines and ROS occurs and how they can be interconnected. The concomitant presence of these factors can elicit peculiar and not fully characterized responses on the heart. We will approach the existing data with new perspectives as they can help explaining several controversial results regarding cardiovascular diseases and the redox ability of catecholamines.

The effect of the head-group spacer length of 12-s-12 gemini surfactants in the host-guest association with ß-cyclodextrin.

NMR spectroscopy has been used to study and characterize the interactions in solution between ß-CD and alkyl-α,ω-bis(dodecyldimethyl ammonium bromide) gemini surfactants with the following head-group spacer lengths: 2, 4, 6, 8, and 10. The application of the method of continuous variation gives as a result that 1:1 and 2:1 (ß-cyclodextrin-gemini) complexes are formed; the association stoichiometry is dependent on the spacer chain length, varying from 1.5 (for s=2) to 1.8 (for s=10). Assuming a two-step mechanism, the binding constants have been computed. In general, the overall binding constant slightly increases with an increase of the number of methylene groups in the spacer. The (1)H NMR spectra of the N-(CH(3))(2) groups in ß-cyclodextrin/gemini mixed solutions are split into two peaks for 12-10-12, suggesting that the gemini spacer can thread the ß-cyclodextrin so that the latter is positioned between the gemini head-groups. Inspection of the ROESY spectra allowed the establishment of several spatial proximities between the protons from the ß-CD and the gemini and for a spacer length of 10, the data indeed indicate that complexes are formed with the CD molecule positioned between the two charged head groups with the spacer passing through the CD molecule.