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1.
Toxicol Appl Pharmacol ; : 117049, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39098745

RESUMEN

Both copper and zinc are known to be important for maintaining health, but most research has focused on deficiencies of these elements. Recent studies have shown that high levels of Cu can be toxic, especially to the cardiovascular (CV) system. However, little research has been done on the effects of higher levels of Zn on the CV system. In this study, male Wistar rats aged 12 months were given a diet with twice the recommended daily allowance of zinc (31.8 mg/kg of diet) and compared to a control group (15.9 mg/kg of diet) after 8 weeks. Blood plasma and internal organs of both groups were examined for levels of copper, zinc, selenium and iron, as well as several key enzymes. Aortic rings from both groups were also examined to determine vascular functioning. There were very few changes in the vascular system functioning after chronic exposure to zinc, and only one enzyme, heme oxygenase-1 (HO-1) was elevated, whereas vascular contraction to noradrenaline decreased with no changes in vasodilation to acetylcholine. Of the micronutrients, zinc and selenium were elevated in the blood plasma, while copper decreased. Meanwhile, the total antioxidant status increased. These were not observed in the liver. Therefore, it is proposed that there is a mechanism in place within the vascular system to protect against the overproduction of heme, caused by chronic zinc exposure.

2.
Int J Mol Sci ; 24(10)2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37240271

RESUMEN

Articular cartilage has very low metabolic activity. While minor injuries may be spontaneously repaired within the joint by chondrocytes, there is very little chance of a severely impaired joint regenerating itself when damaged. Therefore, any significant joint injury has little chance of spontaneously healing without some type of therapy. This article is a review that will examine the causes of osteoarthritis, both acute and chronic, and how it may be treated using traditional methods as well as with the latest stem cell technology. The latest regenerative therapy is discussed, including the use and potential risks of mesenchymal stem cells for tissue regeneration and implantation. Applications are then discussed for the treatment of OA in humans after using canine animal models. Since the most successful research models of OA were dogs, the first applications for treatment were veterinary. However, the treatment options have now advanced to the point where patients suffering from osteoarthritis may be treated with this technology. A survey of the literature was performed in order to determine the current state of stem cell technology being used in the treatment of osteoarthritis. Then, the stem cell technology was compared with traditional treatment options.


Asunto(s)
Cartílago Articular , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Osteoartritis , Humanos , Animales , Perros , Células Madre , Condrocitos , Osteoartritis/terapia
3.
Nutrients ; 14(5)2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-35268093

RESUMEN

Oxidative stress induces functional changes in arteries. Therefore, the effect of myo-inositol, a possible anti-inflammatory/antioxidant agent was studied on human plasma and rat thoracic arteries. Aortic rings from male Wistar rats (3 months of age) were incubated with myo-inositol (1, 10 and 100 µM, 120 min) and analyzed using the gas chromatography (GC) method. In another experiment, aortic rings were protected first with myo-inositol (1 µM, 60 min) and then subjected to a thromboxane receptor agonist (U-46619, 0.1 nM, 60 min). Therefore, these four groups under the following conditions were studied: (i) the control in the vehicle; (ii) myo-inositol; (iii) the vehicle plus U-46619; (iv) myo-inositol plus U-46619. The hemostatic parameters of human plasma and an H2O2/Fe2+ challenge for lipid and protein peroxidation were also performed. Myo-inositol was not absorbed into the pre-incubated aortic rings as measured by the GC method (0.040 µg/mg, p ≥ 0.8688). The effect of myo-inositol was more significant in the impaired arteries due to U-46619 incubation, which resulted in an improved response to acetylcholine (% Emax: 58.47 vs. 86.69), sodium nitroprusside (logEC50: −7.478 vs. −8.076), CORM-2 (% Emax: 44.08 vs. 83.29), pinacidil (logEC50: −6.489 vs. −6.988) and noradrenaline (logEC50: −7.264 vs. −6.525). This was most likely a possible response to increased nitric oxide release (×2.6-fold, p < 0001), and decreased hydrogen peroxide production (×0.7-fold, p = 0.0012). KCl-induced membrane depolarization was not modified (p ≥ 0.4768). Both the plasma protein carbonylation (×0.7-fold, p = 0.0006), and the level of thiol groups (×3.2-fold, p = 0.0462) were also improved, which was not significant for TBARS (×0.8-fold, p = 0.0872). The hemostatic parameters were also not modified (p ≥ 0.8171). A protective effect of myo-inositol was demonstrated against prooxidant damage to human plasma and rat thoracic arteries, suggesting a strong role of this nutraceutical agent on vasculature which may be of benefit against harmful environmental effects.


Asunto(s)
Peróxido de Hidrógeno , Inositol , Animales , Hemodinámica , Inositol/farmacología , Masculino , Ratas , Ratas Wistar , Resistencia Vascular
4.
Toxics ; 9(5)2021 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-34070027

RESUMEN

Bisphenol A (BPA) is an endocrine-disrupting compound (EDC) that can be found nearly everywhere in our polluted world. BPA has been correlated with pathophysiologies that include psychological disorders, especially in children. This study used juvenile porcine models to investigate the effects of BPA on the liver of developing vertebrates in order to determine the effects of BPA on innervated hepatic samples with the use of double-labeled immunofluorescence. This study specifically investigated the sympathetic nervous system (SNS) colocalized with a specific neural marker (PACAP) that has previously been correlated with specific pathophysiologies in the literature. In the liver, it was observed that there were significantly increased nerve fibers in the SNS colocalized with the neural marker PACAP after exposure to BPA at concentrations considered to be "safe" with the same or more profound effects at higher exposure levels. The implications of childhood exposure to BPA are then discussed with regard to several correlation studies that have linked BPA exposure to behavioral/psychological disorders. It is possible that BPA exposure in childhood may upregulate the SNS and PACAP levels, thereby contributing to the correlations in the literature.

5.
Nutrients ; 12(2)2020 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-32092919

RESUMEN

In recent years, bisphenol analogues such as bisphenol S (BPS) have come to replace bisphenol A in food packaging and food containers, since bisphenol A (BPA) has been shown to leach into food and water, causing numerous negative health effects. Unfortunately, little or no research was done to determine the safety of these BPA-free products before they were marketed to the public as a healthier alternative. The latest studies have shown that some of these bisphenol analogues may be even more harmful than the original BPA in some situations. This article used a literature survey to investigate the bisphenol analogue BPS and compare it to BPA and other analogues with regards to increased obesity, metabolic disorders, cancer, and reproductive defects; among others. It was found that BPS works via different pathways than does BPA while causing equivalent obesogenic effects, such as activating preadipocytes, and that BPS was correlated with metabolic disorders, such as gestational diabetes, that BPA was not correlated with. BPS was also shown to be more toxic to the reproductive system than BPA and was shown to hormonally promote certain breast cancers at the same rate as BPA. Therefore, a strong argument may be made to regulate BPS in exactly the same manner as BPA.


Asunto(s)
Compuestos de Bencidrilo/toxicidad , Contaminación de Alimentos/análisis , Obesidad/etiología , Fenoles/toxicidad , Sulfonas/toxicidad , Embalaje de Alimentos , Humanos
6.
Toxicol Appl Pharmacol ; 390: 114877, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31917326

RESUMEN

Copper (Cu) deficiency plays an important role in the development of cardiovascular disorders. Resveratrol (RSV) possesses pleiotropic cardiovascular benefits; however, the mechanism(s) by which RSV exerts protective effects are not completely understood. Male Wistar rats at 6 weeks of age were fed for 8 weeks with a Cu deficient diet (no added Cu, Cu = 0). In addition, Cu deficient rats were supplemented with RSV (500 mg/kg of diet, n = 9). Blood and intestinal samples were taken for further analysis together with internal organs and thoracic arteries. RSV supplementation resulted in elevated blood plasma levels of Cu (x2.1) and Zn (x1.1), in an increased activity of superoxide dismutase (SOD, x1.5) and ferric reducing antioxidant power (FRAP, x1.2). Meanwhile, markers of lipid peroxidation expressed as malondialdehyde (MDA, x1.5) and lipid hydroperoxides (LOOH, x1.1) were also increased in a significant way. Food intake, body weight, blood glucose, catalase, ceruloplasmin, lipid profile and intestinal samples were not modified. RSV enhanced the vasoconstriction of isolated thoracic arteries to noradrenaline (x1.4), potentiated the vasodilation to acetylcholine (ACh, x1.4) and increased the sensitivity to sodium nitroprusside (SNP). In addition, preincubation with the cyclooxygenase (COX)-inhibitor, indomethacin, potentiated the ACh-induced vasodilation, which was more pronounced in animals not supplemented with RSV. The KATP channel opener, pinacidil, induced a similar response in both studied groups. In conclusion, this study demonstrates that RSV supplementation influences oxidative stress and the antioxidant status, which may modify the vascular response in Cu deficiency.


Asunto(s)
Antioxidantes/farmacología , Cobre/sangre , Resveratrol/farmacología , Arterias Torácicas/efectos de los fármacos , Zinc/sangre , Animales , Antioxidantes/metabolismo , Glucemia , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratas , Ratas Wistar , Arterias Torácicas/fisiología , Vasoconstricción/efectos de los fármacos , Vasodilatación/efectos de los fármacos
7.
Toxicol Res (Camb) ; 7(3): 371-380, 2018 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-30090587

RESUMEN

Bisphenol compounds are a class of chemical epoxy resins that are found throughout the world in food packaging, thermal paper products, dental materials, and more. These compounds were deemed to be safe until recently, when some studies noticed adverse effects at very low doses, due to the fact that bisphenol acts as an endocrine disruptor. Over the last ten years, studies have been performed to detect bisphenols (especially BPA) in serum and blood samples throughout the world. Essentially, the majority of the earth's population seems to have significantly measurable levels of bisphenol in their blood plasma or urine. However, the majority of the population is unaware that a potential danger may exist. The purpose of this mini-review is to report upon the state of bisphenol research in the lesser developed member-states of the European Union and to increase awareness of the exposure level and possible adverse health effects of this endocrine disruptor. The results show that only three of the most newly admitted members of the European Union have published research concerning the health effects and/or environmental exposure of EU citizens to bisphenol compounds. Those countries were Slovenia, Poland and the Czech Republic. The rest of the surveyed member-states had little or no published research in relation to bisphenol compounds. Furthermore, even the three nations referred to above still lagged far behind the more advanced EU member-states. The lack of research could translate into a lack of awareness amongst the citizenry of nearly half of the EU, and may be unnecessarily putting those EU citizens at an increased risk of exposure.

8.
Folia Histochem Cytobiol ; 1(2): 113-121, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29888781

RESUMEN

INTRODUCTION: Bisphenol A (BPA) is used in the chemical industry for manufacturing plastics which are used as food packaging. Data indicate that BPA is released from such products and is widely present in the environment and the human body. So far, the EFSA and the US FDA have determined "safe" BPA oral exposure levels, and a large amount of data indicates that BPA is harmful even at low-doses. Our previously performed analyses concerning BPA exposure demonstrated the impact of this substance on parasympathetic and peptidergic nerve fibers present within the liver. Therefore, this study concerns BPA exposure and sympathetic intrahepatic in-nervation in reference to several neuropeptides which modulate neuronal responses: cocaine and amphetamine regulated transcript (CART), galanin (GAL), calcitonin gene-regulated peptide (CGRP) and substance P (SP). MATERIALS AND METHODS: Fifteen young swine at 8 weeks of age were used as experimental models of the juvenile human liver. The pigs were divided into 3 groups and received capsules orally with bisphenol at a dose of 0.05 mg/kg b.w./day; a dose of 0.5 mg/kg b.w./day and placebo capsules as a control. After 28 days of oral BPA intake, the animals were euthanized, perfused with 4% paraformaldehyde (PFA), and livers were collected and fixed in PFA. The cryostat sections were subjected to a routine double-labeling immunofluorescence technique. The primary antibodies were directed against dopamine beta hydroxylase (DbH), which is a marker for sympathetic nerves, and one of the investigated neuropeptides: CART, GAL, CGRP and SP, which co-localized the inves-tigated nerves. Immunoreactive nerves were counted in the liver and the percentage presence of each neuronal combination in particular samples of each experimental group were determined and analyzed statistically. RESULTS: The BPA oral intake at low and ten times higher dosage caused an increase of the number of sympa-thetic nerve fibers within the porcine liver by 48.6% and 63.7%, respectively. Moreover, BPA exposure caused an increased presence of sympathetic nerve fibers in these two experimental groups, which were co-localized with CART and GAL up to 65.9%/173.2% and 147.4%/126.3%, respectively. At the lower BPA doses of 50 µg/kg b.w./day, the percentages of SP+/DbH+ and CGRP+/DbH+ nerve fibers were similar to the control. However at a ten times higher dose, BPA caused an increased number of SP+/ DbH+ and CGRP+/ DbH+ nerve fibers in the liver, up to 46.4% and 73.5% respectively. CONCLUSIONS: BPA caused an increase in the number of sympathetic nerve fibers as well as sympathetic nerve fibers which co-localized with neuropeptides in the porcine liver. The increase in CART and GAL were excep-tionally high even at low BPA doses. BPA food contamination may dysregulate liver sympathetic innervation, and thereby may change the oxygenated blood supply, alter metabolism and disrupt the activity of hepatic pa-renchymal cells.


Asunto(s)
Fibras Adrenérgicas/efectos de los fármacos , Compuestos de Bencidrilo/administración & dosificación , Hígado/efectos de los fármacos , Fenoles/administración & dosificación , Animales , Compuestos de Bencidrilo/farmacología , Relación Dosis-Respuesta a Droga , Femenino , Técnica del Anticuerpo Fluorescente , Fenoles/farmacología , Porcinos
9.
Biomed Res Int ; 2018: 2715831, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29607316

RESUMEN

AIM: The aim of the study was to determine the most commonly diagnosed neoplasms in the MRI scanned patient population and indicate correlations based on the descriptive variables. METHODS: The SPSS software was used to determine the incidence of neoplasms within the specific diagnoses based on the descriptive variables of the studied population. Over a five year period, 791 patients and 839 MRI scans were identified in neoplasm category (C00-D48 according to the International Statistical Classification of Diseases and Related Health Problems ICD-10). RESULTS: More women (56%) than men (44%) represented C00-D48. Three categories of neoplasms were recorded. Furthermore, benign neoplasms were the most numerous, diagnosed mainly in patients in the fifth decade of life, and included benign neoplasms of the brain and other parts of the central nervous system. CONCLUSIONS: Males ≤ 30 years of age with neoplasms had three times higher MRI scans rate than females of the same age group; even though females had much higher scans rate in every other category. The young males are more often selected for these scans if a neoplasm is suspected. Finally, the number of MRI-diagnosed neoplasms showed a linear annual increase.


Asunto(s)
Imagen por Resonancia Magnética , Neoplasias/clasificación , Neoplasias/diagnóstico por imagen , Adulto , Factores de Edad , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/epidemiología , Factores Sexuales
10.
Int J Mol Sci ; 18(12)2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-29244763

RESUMEN

Bisphenol A (BPA) is an extremely common polymer that is used in typical everyday products throughout the world, especially in food and beverage containers. Within the last ten years, it has been found that the BPA monomer tends to leach into foodstuffs, and nanogram concentrations of it may cause a variety of deleterious health effects. These health problems are very evident in developing children and in young adults. The aim of this study was to expose developing pigs to dietary BPA at both legally acceptable and ten-fold higher levels. Livers that had been exposed to BPA showed vacuolar degeneration, sinusoidal dilatation, vascular congestion and glycogen depletion that increased with exposure levels. Furthermore, the livers of these models were then examined for irregularities and double-labeled immunofluorescence was used to check the innervated hepatic samples for varying neuronal expression of selected neuronal markers in the parasympathetic nervous system (PSNS). It was found that both the PSNS and all of the neuronal markers showed increased expression, with some of them being significant even at recommended safe exposure levels. The implications are quite serious since these effects have been observed at recommended safe levels with expression increasing in-line with exposure levels. The increased neuronal markers studied here have been previously correlated with behavioral/psychological disorders of children and young adults, as well as with childhood obesity and diabetes. However, further research must be performed in order to develop a mechanism for the above-mentioned correlations.


Asunto(s)
Compuestos de Bencidrilo/toxicidad , Biomarcadores/sangre , Enfermedad Hepática Inducida por Sustancias y Drogas/sangre , Sistema Nervioso Parasimpático/fisiopatología , Fenoles/toxicidad , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/fisiopatología , Disruptores Endocrinos/toxicidad , Humanos , Hígado/efectos de los fármacos , Hígado/fisiopatología , Sistema Nervioso Parasimpático/efectos de los fármacos , Porcinos
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