Gene expression of T3-regulated genes in a mouse model of the human thyroid hormone resistance.

AIMS: To understand how thyroid hormone (TH) regulates tissue-specific gene expression in patients with the syndrome of resistance to TH (RTHß), we used a mouse model that replicates the human RTHß, specifically the ∆337T mutation in the thyroid hormone receptor ß (THRß). MAIN METHODS: We investigated the expression of key TH target genes in the pituitary and liver of TRß∆337T and wild type THRß mice by qPCR before and after a T3 suppression test consisting of the administration of increasing concentrations of T3 to hypothyroid mice. KEY FINDINGS: Pituitary Tshb and Cga expression decreased and Gh expression increased in TRß∆337T mice after T3 suppression. The stimulation of positively regulated TH genes was heterogeneous in the liver. Levels of liver Me1 and Thsrp were elevated in TRß∆337T mice after T3 administration. Slc16a2 and Gpd2 did not respond to T3 stimulation in the liver of TRß∆337T mice whereas Dio1 response was lower than that observed in WT mice. Moreover, although Chdh and Upd1 genes were negatively regulated in the liver, the expression of these genes was elevated after T3 suppression. We did not observe significant changes in THRα expression in the liver and pituitary, while THRß levels were diminished in the pituitary and increased in the liver. SIGNIFICANCE: Using a model expressing a THRß unable to bind T3, we showed the expression pattern of liver negative and positive regulated genes by T3.

[Hip fracture as risk factor for mortality in patients over 65 years of age. Case-control study]. / Fractura de cadera como factor de riesgo en la mortalidad en pacientes mayores de 65 años. Estudio de casos y controles.

INTRODUCTION: Hip fracture among older patients is a devastating injury in most cases. It profoundly affects the physical, mental, functional and social balance that patients used to have and, beyond the orthopedic injury, it reflects the aging process and its dire consequences. Some reports show that up to 50% of patients with hip fracture die within six months and many of those who survive do not recover their baseline independence and function. In recent decades the increase in life expectancy after 60 years of age has led to an exponential growth in hip fractures. This is why it is essential to determine the patient-related and environmental factors leading to the increased mortality rates seen in patients with hip fracture, to improve the survival and quality of life of older adults. The objective was to determine the association between hip fracture and mortality in patients over 65 years of age. MATERIAL AND METHODS: An observational, longitudinal, retrospective, descriptive, comparative case-control study was conducted. The clinical records of all patients over 65 years of age admitted to the Orthopedics Service, Hospital Regional <>, ISSSTE, with a diagnosis of hip fracture during the previous 12 months were analyzed, regardless of the type of fracture and treatment they received. A group of patients without hip fracture was used as control group. Total sample size was 50 patients with hip fracture and 50 patients without hip fracture. The following data were collected in data collection forms: age, sex, time elapsed since the fracture, survival at one year and, in the case of deceased patients, the cause of death (pneumonia, sepsis, arrhythmia, hydroelectrolytic imbalance, heart failure and others). The results obtained are shown as tables and charts to facilitate their visual understanding. RESULTS: Patient demographics show that there were 40 (80%) female patients and 10 (20%) male patients with a diagnosis of hip fracture. The control group included 35 (70%) females and 15 (30) males. An association between hip fracture and increased mortality was found, with a significant p value of 0.001. The main cause of death among hip fracture patients in our study was sepsis in 7 (35%), while among the control group it was myocardial infarction in 3 (15%). Time wise, mortality was found to be higher within the first six months, with 10 deaths (50%), and within the first year, with six deaths (30%). DISCUSSION: Hip fracture is in fact a risk factor associated with mortality among patients over 65 years of age. Females are the group most prone to sustaining a hip fracture and, therefore, to increased mortality rates. The major cause of death among our patient population was sepsis, apparently caused by mismanagement of soft tissues, a poor aseptic technique during the surgical procedure, a long hospital stay or a poor family support network, and dementia, which is related to poor surgical wound care. The highest mortality rates were found in ages over 90 years, and they were associated with preexisting chronic-degenerative conditions. The age group at highest risk of hip fracture was 80-89 years. Patients with hip fracture should always be managed together with the internist and the geriatrician and they should be considered as orthopedic emergencies, as a long hospital stay and delayed surgical treatment are associated with major complications and increased mortality rates.

The Δ337T mutation on the TRß causes alterations in growth, adiposity, and hepatic glucose homeostasis in mice.

Mice bearing the genomic mutation Δ337T on the thyroid hormone receptor ß (TRß) gene present the classical signs of resistance to thyroid hormone (TH), with high serum TH and TSH. This mutant TR is unable to bind TH, remains constitutively bound to co-repressors, and has a dominant negative effect on normal TRs. In this study, we show that homozygous (TRßΔ337T) mice for this mutation have reduced body weight, length, and body fat content, despite augmented relative food intake and relative increase in serum leptin. TRßΔ337T mice exhibited normal glycemia and were more tolerant to an i.p. glucose load accompanied by reduced insulin secretion. Higher insulin sensitivity was observed after single insulin injection, when the TRßΔ337T mice developed a profound hypoglycemia. Impaired hepatic glucose production was confirmed by the reduction in glucose generation after pyruvate administration. In addition, hepatic glycogen content was lower in homozygous TRßΔ337T mice than in wild type. Collectively, the data suggest that TRßΔ337T mice have deficient hepatic glucose production, by reduced gluconeogenesis and lower glycogen deposits. Analysis of liver gluconeogenic gene expression showed a reduction in the mRNA of phosphoenolpyruvate carboxykinase, a rate-limiting enzyme, and of peroxisome proliferator-activated receptor-γ coactivator 1α, a key transcriptional factor essential to gluconeogenesis. Reduction in both gene expressions is consistent with resistance to TH action via TRß, reproducing a hypothyroid phenotype. In conclusion, mice carrying the Δ337T-dominant negative mutation on the TRß are leaner, exhibit impaired hepatic glucose production, and are more sensitive to hypoglycemic effects of insulin.

Mold-sensitivity in children with moderate-severe asthma is associated with HLA-DR and HLA-DQ.

BACKGROUND: Several epidemiologic studies in the United States and Europe have linked Alternaria sensitivity to both persistence and severity of asthma. In this study, we examined T cell responses and HLA class II alleles in children with moderate-severe asthma. METHODS: Ninety-six children with moderate-severe asthma were compared to 90 children with mild asthma. HLA class II genotyping was performed to determine HLA allelic frequencies. Th1/Th2 Alternaria-specific T cell cytokine responses were determined by the use of Alternaria-stimulated cultures. HLA class II restriction was examined by inhibition of Alternaria-stimulated lymphoproliferative responses with blocking anti-HLA class II monoclonal antibodies. RESULTS: Children with moderate-severe asthma had significantly increased sensitivities to Aspergillus fumigatus; sensitivities to Alternaria were similar in both moderate-severe and mild asthmatics. The frequency of HLA-DRB1*13 alleles were increased in mold-sensitive moderate-severe asthmatic children. HLA-DRB1*03 tended to be increased in mold-sensitive moderate-severe asthmatics. The frequency of HLA-DQB1*03 alleles was significantly decreased in mold and Alternaria-sensitive moderate-severe asthma. HLA class II blocking monoclonal antibodies demonstrated HLA-DR restriction. Alternaria-stimulated IL-5 and IL-13 synthesis was significantly increased in moderate-severe asthmatics. IL-5 and IL-13 synthesis was significantly increased in Alternaria-stimulated lymphocyte cultures of HLA-DQB1*03- asthmatics compared to HLA-DQB1*03+ asthmatics. CONCLUSIONS: In children with Alternaria-sensitive moderate-severe asthma, there was increased Th2 sensitivity to Alternaria stimulation. This was associated with HLA-DR restriction and with increased frequency of HLA-DRB1*13 and HLA-DRB1*03. There was decreased frequency of HLA-DQB1*03 in Alternaria-sensitive moderate-severe asthma, suggesting HLA-DQB1*03 may be protective of the development of Alternaria-sensitive severe asthma.

Effects of bio-normalizer (a food supplementation) on free radical production by human blood neutrophils, erythrocytes, and rat peritoneal macrophages.

Bio-normalizer, a natural Japanese health food prepared by the fermentation of Carica papaya, exhibits therapeutic properties against various pathologies including tumors and immunodeficiency. To understand the mechanism of bio-normalizer's therapeutic effects, we studied its action on the production of active oxygen species in cell-free systems (the Fenton reaction, the xanthine-xanthine oxidase system, and the hydrogen peroxide-hypochloride or hydrogen peroxide-horseradish peroxidase systems) and by human blood neutrophils and erythrocytes and rat peritoneal macrophages. Bio-normalizer efficiently inhibited the formation of oxygen radicals in cell-free systems and partly decreased spontaneous and menadione-stimulated superoxide production by erythrocytes, but manifested both stimulatory and inhibitory effects on oxygen radical release by dormant and activated phagocytes (neutrophils and macrophages). We suggest that bio-normalizer is able to enhance the intracellular production of innocuous superoxide ion and, at the same time, to diminish the formation of reactive hydroxyl radicals, perhaps by the inactivation of ferrous ions, the catalysts of the superoxide-driven Fenton reaction. We also propose that the normalization of an organism's superoxide level is one of the molecular mechanisms of bio-normalizer activity.

Antioxidant defenses of baker's yeast against free radicals and lipid peroxides in rat brain.

We examined through the electron spin resonance spectrometry/spin trapping technique the antioxidant activity of baker's yeast Saccharomyces cerevisiae which is known to have both enzymatic and nonenzymatic antioxidants. The components in baker's yeast were separated by differential filtration/centrifugation using centrifuge-type filter tubes, yielding four nonenzymatic thermostable fractions of varied molecular weights which scavenged 85-95% of 1,1-diphenyl-2-picrylhydrazyl in organic solution, of hydroxyl and superoxide radicals in aqueous solution, and of lipid carbon-centered radicals induced by equimolar mixture of ascorbic acid and Fe(II) salt in rat brain homogenate. Baker's yeast also inhibited the thiobarbituric acid-reactive substance formation in the cortex, midbrain, pons-medulla oblongata, cerebellum, hippocampus, and striatum. Partial characterization of the antioxidative defenses in baker's yeast against free radicals and lipid peroxides in the brain confirmed the presence of superoxide dismutase, catalase, peroxidase, and glutathione.

Antioxidant protection of bio-normalizer in cerebral ischaemia-reperfusion injury in the gerbil.

In this study we used cerebral ischaemia-reperfusion injury (IRI) as an experimental model to analyse the effects of Bio-normalizer (BN, a naturally fermented health food product) on reactive oxygen species related changes in different brain regions of gerbils. Pre-administration of BN solutions (0.1% and 1%) for 45 days produced a significant reduction in IRI-mediated increase in membrane lipid peroxidation, as shown by the decreased carbon-centred radicals and thiobarbituric acid-reactive substances in several brain regions including the cerebral cortex, the hippocampus and the striatum. BN however has no effect on the mitochondrial superoxide dismutase activity.

Age-related increases in superoxide dismutase activity and thiobarbituric acid-reactive substances: effect of bio-catalyzer in aged rat brain.

This study describes, using electron spin resonance spectrometry/spin trapping technique, the increase superoxide dismutase (SOD) activity in the mitochondrial and cytosolic fraction of the cortex, midbrain, pons-medulla oblongata and cerebellum, and in thiobarbituric acid-reactive substances (TBARS) in the cortex, cerebellum and hippocampus of the aged rats. The results show that corresponding to the increased life span and improved physical conditions observed after peroral long-term treatment with Bio-catalyzer, a commercial natural fermented health food supplement marketed in Japan and in the Philippines and earlier reported to be a hydroxyl radical scavenger with weaker scavenging activity on superoxide radical (O-2), SOD which is involved in the metabolic degradation of O-2 was further increased, whereas TBARS decreased. These findings suggest that the increased SOD activity in the brain as a defense mechanism against age-related accumulation of reactive oxygen species, in particular superoxide radicals, was enhanced with Bio-catalyzer treatment while age-related peroxidation of neuronal membrane, as measured by TBARS, was decreased.

Antimicrobial and antioxidant activities of unripe papaya.

The meat, seed and pulp of Carica papaya Linn., a popular traditional medicinal herb grown in the tropics, was shown by the agar-cup method to be bacteriostatic against several enteropathogens such as Bacillus subtilis, Enterobacter cloacae, Escherichia coli, Salmonella typhi, Staphylococcus aureus, Proteus vulgaris, Pseudomonas aeruginosa, and Klebsiella pneumoniae. The same parts of papaya were unequivocably demonstrated by electron spin resonance spectrometry to scavenge 1,1-diphenyl-2-picrylhydrazyl (5.8 x 10(14) spins/ml), hydroxyl (5.1 x 10(14) spins/ml) and superoxide (1.2 x 10(14) spins/ml) radicals with the seed giving the highest activity at concentrations (IC50) of 2.1, 10.0 and 8.7 mg/ml, respectively. The superoxide dismutase (SOD)-like activity in the meat, seed and pulp amounts to about 32, 98 and 33 units/ml; comparable to those of soybean paste miso, rice bran and baker's yeast. Vitamin C, malic acid, citric acid and glucose are some of the possible antioxidative components in papaya. Our study correlates the bacteriostatic activity of papaya with its scavenging action on superoxide and hydroxyl radicals which could be part of the cellular metabolism of such enteropathogens. This is indicative of the pathophysiological role of these reactive oxygen species in gastrointestinal diseases and papaya's ability to counteract the oxidative stress.

Japanese soybean paste miso scavenges free radicals and inhibits lipid peroxidation.

Japanese soybean paste miso, which has been reported to prevent gastric and mammary cancer and chronic nephritis, was demonstrated by electron spin resonance spectrometry using 5,5'-dimethyl-1-pyrroline-N-oxide as a scavenger of free radicals. Fifty mg/ml of miso scavenged 100% of 1,1-diphenyl-2-picrylhydrazyl radicals (3.9 x 10(15) spins/ml); 45 mg/ml quenched 92% of hydroxyl radicals (7.9 x 10(16) spins/ml); and 50 mg/ml quenched 50% of superoxide anion (6.7 x 10(16) spins/ml). In the system of rat cerebral cortex homogenate supplemented with 2 mM each of Fe2+ and ascorbic acid, 90% and 82% of the hydrogen and carbon-centered radicals having 1.7 x 10(13) spins/ml and 3.9 x 10(13) spins/ml, respectively, were quenched by 180 mg/ml of miso. The thiobarbituric acid-reactive substances, an index of lipid peroxidation in the brain, was inhibited by 10 mg/ml of miso. These results showed that miso acts as an antioxidant by scavenging free radicals.

Free radical scavenging action of Bio-catalyzer alpha.rho No.11 (Bio-normalyzer) and its by-product.

Bio-catalyzer alpha.rho No.11 (Bio-normalyzer) and its by-product are natural health products made by yeast fermentation of glucose, Carica papaya Linn., Pennisetum pupureum Schum., and Sechium edule Swartz. Their effects on free radicals were examined by electron spin resonance spectrometry using spin trapping agent 5,5-dimethyl-1-pyrroline-1-oxide (DMPO). It was observed that both Bio-catalyzer and its by-product scavenged 95% of DMPO-OH spin adducts (89 x 10(15) spins/ml) generated by FeSO4-H2O2-diethylene triamine pentaacetic acid system at 45.45 mg/ml each. Five percent of DMPO-O2- spin adducts (27 x 10(15) spins/ml) generated by hypoxanthine-xanthine oxidase system and 11% of 1,1-diphenyl-2-picrylhydrazyl radicals (7 x 10(15) spins/ml) were quenched using 25 mg/ml of Bio-catalyzer while 5% of superoxide and nil DPPH radicals were scavenged by its by-product. Vivo tests showed that oral administration of 1-g/kg body weight of Bio-catalyzer significantly inhibited thiobarbituric acid reactive substances formation, which is an index of lipid peroxidation, in the FeCl3-induced epileptic focus of rats. These findings suggest that Bio-catalyzer or its by-product may be useful health foods against neural lipid peroxidation, traumatic epilepsy and aging.