Fatal gastric distension in a gold thioglucose mouse model of obesity.

This case report addresses the problem of underreporting negative results and adverse side effects in animal testing. We present our findings regarding a hyperphagic mouse model associated with unforeseen high mortality. The results outline the necessity of reporting detailed information in the literature to avoid duplication. Obese mouse models are essential in the study of obesity, metabolic syndrome and diabetes mellitus. An experimental model of obesity can be induced by the administration of gold thioglucose (GTG). After transcending the blood-brain barrier, the GTG molecule interacts with regions of the ventromedial hypothalamus, thereby primarily targeting glucose-sensitive neurons. When these neurons are impaired, mice become insensitive to the satiety effects of glucose and develop hyperphagia. In a pilot study for optimising dosage and body weight development, C57BL/6 mice were treated with GTG (0.5 mg/g body weight) or saline, respectively. Animals were provided a physiological amount of standard diet (5 g per animal) for the first 24 hours after treatment to prevent gastric dilatation. Within 24 hours after GTG injection, all GTG-treated animals died of gastric overload and subsequent circulatory shock. Animals developed severe attacks of hyperphagia, and as the amount of provided chow was restricted, mice exhibited unforeseen pica and ingested bedding material. These observations strongly suggest that restricted feeding is contraindicated concerning GTG application. Presumably, the impulse of excessive food intake was a strong driving force. Therefore, the actual degree of suffering in the GTG-induced model of hyperphagia should be revised from moderate to severe.

Increased radiotoxicity in two cancerous cell lines irradiated by low and high energy photons in the presence of thio-glucose bound gold nanoparticles.

PURPOSE: Gold nanoparticles modified by thio-glucose are believed to increase the toxicity of radiotherapy in human malignant cells. We report the effect of thio-glucose bound gold nanoparticles (Glu-G nanoparticles), 16 nm in size, on two human lung (QU-DB) and breast (MCF7) cancer cell lines combined with kilo and megavoltage X-rays. MATERIALS AND METHODS: The shape and surface characteristics, the size distribution and light absorption spectrum of the prepared nanoparticles were measured by transmission electron microscopy, dynamic light scattering, and ultraviolet-visible spectrophotometry, respectively. The cell uptake was assayed using the atomic absorption spectrometry. Mitochondrial activity, colony formation, and comet assays were applied to assess and compare the enhanced radiotoxicity of 100 KV and 6 MV X-rays, when combined with Glu-G nanoparticles. RESULTS: Glu-G nanoparticles had no significant toxicity for MCF7 and QU-DB cells up to 100 micromolar concentration. Compared to radiation alone, the intracellular uptake of Glu-G nanoparticles resulted in increased inhibition of cell proliferation by 64.1% and 38.7% for MCF7 cells, and 64.4% and 32.4% for QU-DB cells by 100 kVp and 6 MV X-rays, respectively. Comet assay confirmed an increase of DNA damage as a result of combination of 6 MV photons with Glu-G nanoparticles. CONCLUSION: Glu-G nanoparticles have remarkable potential for enhancing radiotoxicity of both low and high energy photons in MCF7 and QU-DB cells.

Localized chrysiasis, aluminum salt deposition and dystrophic calcification a decade after gold injections.

Localized chrysiasis is rare and can occur in two settings: after localized or traumatic implantation of elemental gold or gold salts or after localized laser or light therapy in someone who has been previously exposed to systemic gold therapy. We report a unique case of localized chrysiasis with associated aluminum salt deposition and sclerosing lipogranulomas because of previous injections of aurothioglucose (Solganal®). The unique histopathologic findings seen in this case have not been previously reported.

The thioredoxin reductase-1 inhibitor aurothioglucose attenuates lung injury and improves survival in a murine model of acute respiratory distress syndrome.

AIMS: Inflammation and oxygen toxicity increase free radical production and contribute to the development of acute respiratory distress syndrome (ARDS), which is a significant cause of morbidity and mortality in intensive care patients. We have previously reported increased glutathione (GSH) levels in lung epithelial cells in vitro and attenuated adult murine hyperoxic lung injury in vivo after pharmacological thioredoxin reductase-1 (TrxR1) inhibition. Using a murine ARDS model, we tested the hypothesis that aurothioglucose (ATG) treatment increases pulmonary GSH levels, attenuates lung injury, and decreases mortality in a GSH-dependent manner. RESULTS: Adult mice received a single intratracheal dose of 0.375 µg/g lipopolysaccharide (LPS) 12 h before a single intraperitoneal injection of 25 mg/kg ATG. Control mice received intratracheal and/or intraperitoneal saline. Mice were then exposed to room air or hyperoxia (>95% O2). Lung injury was assessed by bronchoalveolar lavage protein concentrations. Expression of glutamate-cysteine ligase modifier subunit (GCLM), GSH, cytokines, and chemokines was determined. Exposure to LPS/hyperoxia induced inflammation and lung injury. ATG treatment significantly attenuated lung injury, increased lung GCLM expression and GSH levels, and decreased mortality. GSH depletion completely prevented the protective effects of ATG in LPS/hyperoxia-exposed mice. INNOVATION: ATG treatment significantly attenuates lung injury and enhances survival in a clinically relevant murine model of ARDS. The protective effects of ATG are GSH dependent. CONCLUSION: Augmentation of GSH systems by TrxR1 inhibition could represent a promising therapeutic approach to attenuate oxidant-mediated lung injury and improve patient outcomes.

A novel and comprehensive mouse model of human non-alcoholic steatohepatitis with the full range of dysmetabolic and histological abnormalities induced by gold thioglucose and a high-fat diet.

BACKGROUND: The search for effective treatments of non-alcoholic steatohepatitis (NASH), now the most common chronic liver disease in affluent countries, is hindered by a lack of animal models having the range of anthropometric and pathophysiological features as human NASH. AIMS: To examine if mice treated with gold thioglucose (GTG) - known to induce lesions in the ventromedial hypothalamus, leading to hyperphagia and obesity - and then fed a high-fat diet (HF) had a comprehensive histological and dysmetabolic phenotype resembling human NASH. METHODS: C57BL/6 mice were injected intraperitoneally with GTG and then fed HF for 12 weeks (GTG+HF). The extent of abdominal adiposity was assayed by CT scanning. A glucose tolerance test and an insulin tolerance test were performed to evaluate insulin resistance (IR). Histological, molecular and biochemical analyses were also performed. RESULTS: Gold thioglucose+HF induced dysmetabolism, with hyperphagia, obesity with increased abdominal adiposity, IR and consequent steatohepatitis, with hepatocyte ballooning, Mallory-Denk bodies, perivenular and pericellular fibrosis as seen in adult NASH, paralleled by an increased expression of the profibrogenic factors, transforming growth factor-ß1 and TIMP-1. Plasma adiponectin and the expression of adiponectin receptor 1 and receptor 2 were decreased, while PPAR-γ and FAS were increased in the livers of GTG+HF mice. In addition, GTG+HF mice showed glucose intolerance and severe IR. CONCLUSIONS: Treatment with GTG and HF diet induce, in mice, a comprehensive model of human NASH, with the full range of dysmetabolic and histological abnormalities.

Differential response of arcuate proopiomelanocortin- and neuropeptide Y-containing neurons to the lesion produced by gold thioglucose administration.

The effect of gold thioglucose (GTG) administration on neurons containing feeding-related peptides in the hypothalamic arcuate nucleus was examined in mice. Intraperitoneal GTG injection increased the body weight and produced a hypothalamic lesion that extended from the ventral part of the ventromedial nucleus to the dorsal part of the arcuate nucleus. Neurons containing proopiomelanocortin (POMC) and neuropeptide Y (NPY) present in the dorsal part of the arcuate nucleus were destroyed by GTG. In addition, the peptide-containing fibers that extended from the remaining arcuate neurons were degenerated at the lesion site. The number of POMC-containing fibers in the paraventricular nucleus, dorsomedial nucleus, and lateral hypothalamus was found to have decreased significantly when examined at 2 days and 2 weeks after the GTG treatment. In contrast, the number of NPY-containing fibers in the lateral hypothalamus remained unchanged after the GTG treatment, probably because of the presence of an unaffected NPY-containing fiber pathway passing through the tuberal region and projecting onto the lateral hypothalamus. The number of NPY-immunoreactive fibers in the paraventricular and dorsomedial nuclei showed a moderate but significant decrease at 2 days after the GTG treatment, but it recovered to the normal levels 2 weeks later. The NPY-containing fibers were found to have regenerated across the lesion site 2 weeks later, and this might contribute to the recovery of the NPY-immunoreactive fibers in these regions. The present results first demonstrate that POMC- and NPY-containing neurons in the arcuate nucleus respond differently to the lesion produced by the GTG treatment.

Beneficial effects of Zingiber officinale on goldthioglucose induced obesity.

Goldthioglucose induces in mice a significant increase in body weight, glucose, insulin and lipid levels. Treatment with 250 mg/kg of methanol and ethyl acetate extracts of Zingiber officinale for 8 weeks produces significant reduction in body weight, glucose, insulin and lipid levels as compared to obese control mice. The reduction in elevated glucose along with elevated insulin levels indicates that the treatment with Z. officinale improves insulin sensitivity.

Selenium supplementation acting through the induction of thioredoxin reductase and glutathione peroxidase protects the human endothelial cell line EAhy926 from damage by lipid hydroperoxides.

The human endothelial cell line EAhy926 was used to determine the importance of selenium in preventing oxidative damage induced by tert-butyl hydroperoxide (tert-BuOOH) or oxidised low density lipoprotein (LDLox). In cells grown in a low selenium medium, tert-BuOOH and LDLox killed cells in a dose-dependent manner. At 555 mg/l LDLox or 300 microM tert-BuOOH, >80% of cells were killed after 20 h. No significant cell kill was achieved by these agents if cells were pre-incubated for 48 h with 40 nM sodium selenite, a concentration that maximally induced the activities of cytoplasmic glutathione peroxidase (cyGPX; 5.1-fold), phospholipid hydroperoxide glutathione peroxidase (PHGPX;1.9-fold) and thioredoxin reductase (TR; 3.1-fold). Selenium-deficient cells pre-treated with 1 microM gold thioglucose (GTG) (a concentration that inhibited 25% of TR activity but had no inhibitory effect on cyGPX or PHGPX activity) were significantly (P<0.05) more susceptible to tert-BuOOH toxicity (LC(50) 110 microM) than selenium-deficient cells (LC(50) 175 microM). This was also the case for LDLox. In contrast, cells pre-treated with 40 nM selenite prior to exposure to GTG were significantly more resistant to damage from tert-BuOOH and LDLox than Se-deficient cells. Treatment with GTG or selenite had no significant effect on intracellular total glutathione concentrations. These results suggest that selenium supplementation, acting through induction of TR and GPX, has the potential to protect the human endothelium from oxidative damage.

[Chrysiasis]. / Chrysiasis.

We describe the case of a 78-year old woman, with rheumatoid arthritis, 3 years of regular parenteral gold administration and Chrysiasis. Chrysiasis is a rare permanent pigmentation of the skin resulting from the parenteral administration of gold. The cause of the pigmentation is multifactorial and not fully established at the moment.

Nitritoid reactions: case reports, review, and recommendations for management.

OBJECTIVE: We assessed nitritoid reactions, which are a well recognized side effect of chrysotherapy that occur in roughly 5% of patients taking gold sodium thiomalate (GST). METHODS: Between January 1996 and January 2000, 8 patients followed in our gold monitoring program at Mary Pack Arthritis Centre experienced nitritoid reactions observed by the clinic nurse. We undertook a chart review to determine the risk factors, timing, course, and outcome of nitritoid reactions. RESULTS: Patients' ages ranged from 36 to 69 years, and 7 of 8 were women. Duration of gold therapy prior to nitritoid reactions ranged from 13 months to 13 years. Seven had previously had mucocutaneous reactions, and one experienced gold dermatitis following a nitritoid reaction. Two of 8 patients were taking angiotensin converting enzyme inhibitor agents. Seven reactions were classified as mild, and one was a severe reaction with hypotension, syncope, and angina. CONCLUSIONS: Management includes a high index of suspicion in patients experiencing nausea, flushing, or dizziness following gold injections, switching from GST to gold sodium aurothioglucose, injection in the recumbent position, and observation for 20 minutes after injections in individual patients.

[Chrysiasis]. / Chrysiasis.

We describe the case of a 78-year old woman, with rheumatoid arthritis, 3 years of regular parenteral gold administration and Chrysiasis. Chrysiasis is a rare permanent pigmentation of the skin resulting from the parenteral administration of gold. The cause of the pigmentation is multifactorial and not fully established at the moment.

Lesions of glucose-responsive neurons impair synchronizing effects of calorie restriction in mice.

Calorie restriction can induce phase-advances of daily rhythms in rodents exposed to light-dark cycles. To test whether glucose-responsive neurons are involved in the synchronizing effects of calorie restriction, C57BL/6J mice were injected with gold-thioglucose (GTG; 0.6 g/kg) which damages glucose-responsive neurons, primarily located in the ventromedial hypothalamus. From the day of injection, GTG-treated and control mice received a hypocaloric diet (66% of ad libitum food intake) 2 h after lights on. When mice were transferred to constant darkness after 4 weeks and fed ad libitum, the onset of circadian rhythm of locomotor activity was phase-advanced by 1 h in control but not in GTG-treated mice. Therefore, glucose-responsive neurons in the ventromedial hypothalamus may play a role in the synchronizing effects of calorie restriction on circadian rhythmicity.

Amyloid formation in response to beta cell stress occurs in vitro, but not in vivo, in islets of transgenic mice expressing human islet amyloid polypeptide.

BACKGROUND: Human, but not mouse, islet amyloid polypeptide (IAPP) is amyloidogenic. Transgenic mice overexpressing human IAPP in the beta cells of the islets of Langerhans should be useful in identifying factors important for the deposition of IAPP as insoluble amyloid fibrils. MATERIALS AND METHODS: Transgenic mice expressing human IAPP were examined using several experimental models for the production of persistent hyperglycemia, as well as for the overstimulation and/or inhibition of beta cell secretion. Obesity was induced by aurothioglucose. Persistent hyperglycemia was produced by long-term administration of glucocorticosteroids or by partial pancreatectomy. Inhibition of normal beta cell exocytosis by diazoxide administration, with or without concurrent dexamethasone injections, was carried out to increase crinophagy of secretory granules. The human IAPP gene was also introduced into the ab and ob mouse models for diabetes. Finally, isolated islets cultivated in vitro at high glucose concentration were also examined. RESULTS: No amyloid deposits were found in the pancreata of any of the animals, either by light microscopy after Congo red staining or by electron microscopy after immunogold labeling with antibodies specific for human IAPP. Aurothioglucose treatment resulted in increased numbers of granules in the beta cell and the appearance of large lysosomal bodies without amyloid. However, islets from db and ob mice expressing human IAPP cultivated in vitro in the presence of glucocorticosteroid and/or growth hormone, were found to contain extracellular amyloid deposits reacting with antibodies to human IAPP. CONCLUSIONS: Oversecretion of human IAPP or increased crinophagy are not sufficient for amyloid formation. This indicates that other factors must influence amyloid deposition; one such factor may be the local clearance of IAPP.

Anti-inflammatory properties of copper, gold and silver, individually and as mixtures.

It has been previously demonstrated that the mixture of Cu, Au and Ag impaired significantly the clinical and biochemical disorders induced by adjuvant arthritis in the rat. The efficiency of this mixture and of each component was tested on the same animal model. Treated rats were injected daily with either 22.8 micrograms of copper gluconate, 0.2 micrograms of gold thioglucose, 6.8 micrograms of silver proteinate or the blended solution over a period of 29 d. The treatment with the one component solutions was found to have a little or no effect on the plasma levels of fibrinogen, haptoglobin, ceruloplasmin, prostaglandin E2, thromboxane B2, total proteins, Zn, Cu, Mn, Se, Co and Ni, and no significant decrease was observed in the paw oedema resulting from the Freund's adjuvant injection. The treatment with the mixture had a significant preventive effect. Therefore it seems that the administration of low doses of each of the three trace elements have no anti-rheumatic property in the rat. The results indicate an enhanced effect of the metal mixture in the model studied.

The effect of adipose cell size on the measurement of GLUT 4 in white adipose tissue of obese mice

Glucose transporter (GLUT 4) was assessed in subcellular membrane fractions of white adipose tissue (WAT) from obese insulin-resistant aurothioglucose (AuTG)- or monosodium glutamate (MSG)-treated mice. Obesitywas demonstrable by increased body weight and/ or Lee index, as well as by the heavier WAT and brown adipose tissue in relation to similar weights of gastrocnemius and heart. In vivo insulin-resistance in obese animals was suggested by moderate hyperglycemia and severe hyperinsulinemia. Morphological analyses of adipose cells showed a > 10-fold increase in cell volume of obese mice. Subcellular fractionation indicated a reduced (P<0.01) protein membrane content in the fat-free extract (FFE) from obese mice. However, the specific activity of 5'nucleotidase, a plasma membrane (PM) marker, in EFE and PM did not differ among groups. In addition, the total PM enzyme activity per unit of cell surface area was also unchanged. The GLUT 4 content, assessed by Western blotting and expressed per µg membrane protein, was reduced by ~50 percent (P<0.01) in all membrane fractions from obese animals. However, the total FFE GLUT 4 content per cell was increased...

No effect of intramuscular gold therapy on serological parameters of Helicobacter pylori infection in patients with rheumatoid arthritis: a 12 month prospective study.

OBJECTIVES: To assess prospectively the influence of intramuscular gold therapy on Helicobacter pylori serology in patients with rheumatoid arthritis (RA). METHODS: Fifty patients with RA were started on intramuscular gold or chloroquine, as the control group and were followed serologically for H pylori infection for 12 months. RESULTS: Twelve patients treated with gold and eight control patients treated with chloroquine, all with serological evidence for H pylori infection, showed no significant decline of IgA and IgG anti-H pylori antibody levels or serum pepsinogen A and C levels. Total serum IgA and IgG levels declined significantly during gold therapy, while they remained unchanged during chloroquine therapy. CONCLUSIONS: Intramuscular gold therapy in patients with RA does not influence the serological parameters of H pylori infection.

[Fatal diffuse alveolar damage after gold medication]. / Letaler diffuser Alveolarschaden nach Goldmedikation.

We report about the case of a 74-year-old woman who suffered diffuse alveolar damage and consecutive lethal pulmonary failure after gold therapy for rheumatoid arthritis. This is the fourth documented case of fatal pulmonary failure following gold therapy. The clinical findings were dominated by severe dyspnoea that warranted respirator therapy shortly after admission. Chest radiographs showed progressing confluent perihilar patchy infiltrates that suggested interstitial involvement. Steroid therapy had only a short-lasting effect on the respiratory failure, the patient died in prolonged hypoxic circulatory failure. Post-mortem examination showed the organotypical findings of diffuse alveolar damage in proliferative stage with advanced pulmonary fibrosis. With the discontinuation of gold medication and early steroid therapy, this disease which is based on immunological pathomechanisms is usually reversible. Both the knowledge of this entity and early diagnosis are essential for a promising therapeutic intervention.