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1.
CienciaUAT ; 17(2): 146-164, ene.-jun. 2023. tab, graf
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1447826

RÉSUMÉ

RESUMEN Las plantas purificadoras de agua que carecen de un adecuado sistema de control de calidad pueden generar problemas de salud pública. El objetivo de este estudio fue examinar la calidad microbiológica del agua proveniente de pequeñas plantas purificadoras de la ciudad de Puebla, así como, determinar la existencia de bacterias Aeromonas sp y Pseudomonas sp, y caracterizar si presentan un fenotipo patógeno oportunista. Se recolectaron 70 muestras de garrafones de agua de 25 establecimientos. La cuantificación bacteriana se realizó mediante el método de goteo en placa. Se comprobaron los géneros microbianos mediante análisis bioquímico. En las cepas que mostraron discrepancia se utilizó la identificación molecular con base a secuencias parciales del gen 16S rRNA para confirmar su especie y se les evaluaron sus características de patogenicidad: multirresistencia a antibióticos, producción de biopelícula y actividad hemolítica. El 40 % de las plantas purificadoras no cumplieron con la calidad microbiológica del agua para consumo humano. El 41.4 % de los garrafones de agua muestreados incumplió la normativa, presentando coliformes totales 35.7 %, Pseudomonas 30 %, Enterococcus faecalis 8.6 % y bacterias coliformes fecales el 5.7 %. Se obtuvieron 56 aislados, provenientes de los 29 garrafones contaminados; 10 de ellos se caracterizaron molecularmente, resultando 7 aislados relacionados con especies diferentes de P. aeruginosa y 3 con especies de Aeromonas. De los aislados de Pseudomonas, 5 presentaron resistencia a 2 familias de antibióticos y 2 mostraron multirresistencia. El 36 % de los 10 aislados produjeron hemólisis y biopelícula. Dos cepas de Aeromonas mostraron resistencia a Cefalosporina 3a generación pero no produjeron hemólisis. Los 10 aislados analizados fueron clasificados como no patógenos. Es necesario un seguimiento sanitario más estricto para lograr el cumplimiento de las normas nacionales e internacionales relacionadas con el consumo de agua purificada, para evitar dañar la salud de los consumidores.


ABSTRACT Water purification establishments that lack an adequate quality control system can cause public health problems. The objective of this study was to examine the microbiological quality of water from small purification establishments in the city of Puebla, as well as to determine the existence of Aeromonas sp and Pseudomonas sp bacteria, and to characterize whether they present an opportunistic pathogenic phenotype. 70 water jug samples were collected from 25 establishments. Bacterial quantification was performed using the drop plate method. Microbial genera were determined by biochemical analysis using the standard methodology. In the strains that showed discrepancy, molecular identification based on partial sequences of the 16S rRNA gene was used to confirm their species, and their pathogenic characteristics were evaluated: multiresistance to antibiotics, biofilm production, and hemolytic activity. The results showed that 40 % of the purification establishments did not comply with the microbiological quality of water for human consumption. Similarly, 41.4 % of the jugs of water sampled failed to comply with the regulations, presenting total coliforms 35.7 %, Pseudomonas 30 %, Enterococcus faecalis 8.6 % and fecal coliform bacteria 5.7 %. Likewise, 56 isolates were obtained from the 29 contaminated jugs, of which 10 were molecularly characterized, resulting in 4 different species for P. aeruginosa and 3 for Aeromonas. Of the 7 Pseudomonas isolates, 5 presented resistance to 2 families of antibiotics and 2 showed multiresistance. In total, 36 % of the 10 isolates produced hemolysis and biofilm. Two Aeromonas strains showed resistance to 3rd generation Cephalosporin but did not produce hemolysis. The 10 isolates analyzed were classified as non-pathogenic. A stricter sanitary monitoring is necessary to achieve compliance with national and international standards related to the consumption of purified water, to avoid harming the health of consumers.

2.
J Chem Neuroanat ; 129: 102237, 2023 04.
Article de Anglais | MEDLINE | ID: mdl-36736441

RÉSUMÉ

The number of people diagnosed with metabolic syndrome (MetS) has increased dramatically to reach alarming proportions worldwide. The origin of MetS derives from bad eating habits and sedentary lifestyle. Most people consume foods high in carbohydrates and saturated fat. In recent years, it has been reported that alterations in insulin at the brain level could have an impact on the appearance of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, dementia, depression, and other types of disorders that compromise brain function. These alterations have been associated with damage to the structure and function of neurons located in the reptilian and limbic systems, a decrease in dendritic arborization and an exacerbated inflammatory state that impaired learning and memory and increased in the state of stress and anxiety. Although the molecular mechanisms induced by MetS to cause neurodegeneration are not fully understood. The aim of this study is to know the effect of the intake of hypercaloric diets on the structure and function of neurons located in the frontal cortex, hypothalamus and hippocampus and its impact on behavior in rats with metabolic syndrome. In conclusion, the present study illustrated that chronic exposure to hypercaloric diets, with a high content of sugars and saturated fatty acids, induces a proinflammatory state and exacerbates oxidative stress in brain regions such as the hypothalamus, hippocampus, and frontal cortex, leading to dysfunction. metabolism, neuronal damage, and recognition memory loss.


Sujet(s)
Maladie d'Alzheimer , Syndrome métabolique X , Animaux , Rats , Glucides , Régime alimentaire , Alimentation riche en graisse , Syndrome métabolique X/étiologie , Syndrome métabolique X/métabolisme , Neurones/métabolisme , Troubles de la mémoire/métabolisme
3.
Synapse ; 76(9-10): 1-16, 2022 08.
Article de Anglais | MEDLINE | ID: mdl-35709361

RÉSUMÉ

Cadmium (Cd) is a heavy metal classified as a carcinogen whose exposure could affect the function of the central nervous system. Studies suggest that Cd modifies neuronal morphology in the hippocampus and affects cognitive tasks. The oxidative stress pathway is proposed as a mechanism of toxicity. However, this mechanism is not precise yet. This study aimed to evaluate the effect of Cd administration on oxidative stress markers in the male rat's hippocampus. Male Wistar rats were divided into (1) control (drinking water) and (2) treatment with Cd (32.5 ppm of cadmium chloride (CdCl2 ) in water). The Cd was administered for 2, 3, and 4 months. The results show that the oral administration of CdCl2 increased the concentration of Cd in plasma and hippocampus, and this response is time-dependent on its administration. Likewise, it caused an increase in lipid peroxidation and nitrosative stress markers. Moreover, it increased reactive astrogliosis and antioxidant enzyme activity. Consequently, the progression of the oxidative response exacerbated neurodegeneration in hippocampal cells. Our results suggest that Cd exposure induces a severe oxidative response that contributes critically to hippocampal neurodegeneration. It is suggested that exposure to Cd increases the risk of developing neurological diseases, which contributes to a decrease in the quality of life of the human and the environment in which it lives.


Sujet(s)
Antioxydants , Cadmium , Animaux , Antioxydants/pharmacologie , Cadmium/métabolisme , Cadmium/toxicité , Chlorure de cadmium/métabolisme , Chlorure de cadmium/toxicité , Hippocampe/métabolisme , Humains , Peroxydation lipidique , Mâle , Stress oxydatif , Qualité de vie , Rats , Rat Wistar
4.
J Mol Histol ; 53(2): 347-356, 2022 Apr.
Article de Anglais | MEDLINE | ID: mdl-35217964

RÉSUMÉ

Ovarian functions decrease with perimenopause. The ovary has extrinsic innervation, but the neural influence on ovarian functions and dysfunction is not well-studied. The present study aimed to biochemically and morphometrically characterize the intrinsic neurons in ovaries from young adult, middle-aged, and senescent Long Evans CII-ZV rats (3, 12, and 15 months old, respectively). Ovaries were extracted from four rats of each age group (n = 12 total), cryopreserved, and processed for immunofluorescence studies with the primary NeuN/ß-tubulin and NeuN/tyrosine hydroxylase (TH) antibodies. The soma area and number of intrinsic neurons in the ovarian stroma, surrounding follicles, corpus luteum, or cyst were evaluated. The intrinsic neurons were grouped in cluster-like shapes in ovarian structures. In senescent rats, the intrinsic neurons were mainly localized in the ovarian stroma and around the cysts. The number of neurons was lower in senescent rats than in young adult rats (p < 0.05), but the soma size was larger than in young adult rats. Immunoreactivity to TH indicated the presence of noradrenergic neurons in the ovary with the same characteristics as NeuN/ß-tubulin, which indicates that they are part of the same neuronal group. Taken together, the findings indicate that the intrinsic neurons may be related to the loss of ovarian functions associated with aging.


Sujet(s)
Ovaire , Tubuline , Vieillissement , Animaux , Femelle , Rats , Rat Long-Evans , Tyrosine 3-monooxygenase
5.
Neurochem Res ; 46(5): 1151-1165, 2021 May.
Article de Anglais | MEDLINE | ID: mdl-33559829

RÉSUMÉ

The consumption of foods rich in carbohydrates, saturated fat, and sodium, accompanied by a sedentary routine, are factors that contribute to the progress of metabolic syndrome (MS). In this way, they cause the accumulation of body fat, hypertension, dyslipidemia, and hyperglycemia. Additionally, MS has been shown to cause oxidative stress, inflammation, and death of neurons in the hippocampus. Consequently, spatial and recognition memory is affected. It has recently been proposed that metformin decavanadate (MetfDeca) exerts insulin mimetic effects that enhance metabolism in MS animals; however, what effects it can cause on the hippocampal neurons of rats with MS are unknown. The objective of the work was to evaluate the effect of MetfDeca on hippocampal neurodegeneration and recognition memory in rats with MS. Administration of MetfDeca for 60 days in MS rats improved object recognition memory (NORt). In addition, MetfDeca reduced markers of oxidative stress and hippocampal neuroinflammation. Accompanied by an increase in the density and length of the dendritic spines of the hippocampus of rats with MS. We conclude that MetfDeca represents an important therapeutic agent to treat MS and induce neuronal and cognitive restoration mechanisms.


Sujet(s)
Mémoire/effets des médicaments et des substances chimiques , Syndrome métabolique X/traitement médicamenteux , Metformine/usage thérapeutique , Maladies neurodégénératives/traitement médicamenteux , Neuroprotecteurs/usage thérapeutique , Vanadates/usage thérapeutique , Animaux , Catalase/métabolisme , Association médicamenteuse , Hippocampe/effets des médicaments et des substances chimiques , Inflammation/traitement médicamenteux , Inflammation/étiologie , Inflammation/anatomopathologie , Mâle , Syndrome métabolique X/complications , Syndrome métabolique X/anatomopathologie , Maladies neurodégénératives/étiologie , Maladies neurodégénératives/anatomopathologie , Neurones/effets des médicaments et des substances chimiques , Neurones/anatomopathologie , Stress oxydatif/effets des médicaments et des substances chimiques , Rat Wistar , Superoxide dismutase/effets des médicaments et des substances chimiques
6.
Synapse ; 75(6): e22193, 2021 06.
Article de Anglais | MEDLINE | ID: mdl-33141999

RÉSUMÉ

In the aging process, the brain presents biochemical and morphological alterations. The neurons of the limbic system show reduced size dendrites, in addition to the loss of dendritic spines. These disturbances trigger a decrease in motor and cognitive function. Likewise, it is reported that during aging, in the brain, there is a significant decrease in neurotrophic factors, which are essential in promoting the survival and plasticity of neurons. The carboxyl-terminal fragment of the heavy chain of the tetanus toxin (Hc-TeTx) acts similarly to neurotrophic factors, inducing neuroprotection in different models of neuronal damage. The aim here, was to evaluate the effect of Hc-TeTx on the motor processes of elderly mice (18 months old), and its impact on the dendritic morphology and density of dendritic spines of neurons in the limbic system. The morphological analysis in the dendrites was evaluated employing Golgi-Cox staining. Hc-TeTx was administered (0.5 mg/kg) intraperitoneally for three days in 18-month-old mice. Locomotor activity was evaluated in a novel environment 30 days after the last administration of Hc-TeTx. Mice treated with Hc-TeTx showed significant changes in their motor behavior, and an increased dendritic spine density of pyramidal neurons in layers 3 and 5 of the prefrontal cortex in the hippocampus, and medium spiny neurons of the nucleus accumbens (NAcc). In conclusion, the Hc-TeTx improves the plasticity of the brain regions of the limbic system of aged mice. Therefore, it is proposed as a pharmacological alternative to prevent or delay brain damage during aging.


Sujet(s)
Neurones , Toxine tétanique , Animaux , Dendrites/métabolisme , Hippocampe/métabolisme , Système limbique/métabolisme , Souris , Activité motrice , Neurones/métabolisme , Toxine tétanique/métabolisme , Toxine tétanique/pharmacologie , Toxine tétanique/usage thérapeutique
7.
Synapse ; 74(9): e22153, 2020 09.
Article de Anglais | MEDLINE | ID: mdl-32190918

RÉSUMÉ

Metabolic syndrome (MS) is a health problem that is characterized by body fat accumulation, hypertension, dyslipidemia, and hyperglycemia; recently, it has been demonstrated that MS also damages memory processes. The first-line drug in the treatment of MS and type 2 diabetes mellitus is metformin, which is an antihyperglycemic agent. This drug has been shown to produce neuroprotection and to improve memory processes. However, the mechanism involved in this neuroprotection is unknown. A 90-day administration of metformin improved the cognitive processes of rats with MS as evaluated by the novel object recognition test, and this finding could be explained by an increase in the neuronal spine density and spine length. We also found that metformin increased the immunoreactivity of synaptophysin, sirtuin-1, AMP-activated protein kinase, and brain-derived neuronal factor, which are important plasticity markers. We conclude that metformin is an important therapeutic agent that increases neural plasticity and protects cognitive processes. The use of this drug is important in the minimization of the damage caused by MS.


Sujet(s)
Hippocampe/effets des médicaments et des substances chimiques , Hypoglycémiants/pharmacologie , Syndrome métabolique X/physiopathologie , Metformine/pharmacologie , Plasticité neuronale , Neuroprotecteurs/pharmacologie , , AMP-activated protein kinase kinases , Animaux , Facteur neurotrophique dérivé du cerveau/métabolisme , Hippocampe/métabolisme , Hippocampe/physiologie , Hypoglycémiants/administration et posologie , Hypoglycémiants/usage thérapeutique , Mâle , Syndrome métabolique X/traitement médicamenteux , Syndrome métabolique X/métabolisme , Metformine/administration et posologie , Metformine/usage thérapeutique , Neuroprotecteurs/administration et posologie , Neuroprotecteurs/usage thérapeutique , Protein kinases/métabolisme , Rats , Rat Wistar , Sirtuine-1/métabolisme , Synaptophysine/métabolisme
8.
Reprod Biol Endocrinol ; 17(1): 95, 2019 Nov 19.
Article de Anglais | MEDLINE | ID: mdl-31744506

RÉSUMÉ

BACKGROUND: Polycystic ovary syndrome is characterized by hyperactivity of the ovarian sympathetic nervous system, increases in the content and release of norepinephrine, as well as decreases in the number of ß-adrenoreceptors. In the present study, ß-adrenoreceptors in the ovaries of rats with polycystic ovary syndrome were blocked and analyzed the resultant effects on ovulation, hormone secretion and the enzymes responsible for the synthesis of catecholamines. METHODS: At 60 days of age, vehicle or estradiol valerate-treated rats were injected with propranolol [10- 4 M] into the ovarian bursas on oestrus day. The animals were sacrificed on the next day of oestrus, and the ovulation response, the steroid hormone levels in the serum and the immunoreactivity of tyrosine hydroxylase and dopamine ß-hydroxylase in the ovaries were measured. RESULTS: In animals with the induction of polycystic ovary syndrome and ß-adrenoreceptor blocking, ovulation was restored in more than half of the animals and resulted in decreased hyperandrogenism with respect to the levels observed in the estradiol valerate-treated group. Tyrosine hydroxylase and dopamine ß-hydroxylase were present in the theca cells of the growing follicles and the interstitial gland. Injection of propranolol restored the tyrosine hydroxylase and ovarian dopamine ß-hydroxylase levels in rats with polycystic ovary syndrome induction. CONCLUSIONS: The results suggest that a single injection into the ovarian bursas of propranolol, a nonselective antagonist of ß-adrenoreceptor receptors, decreases the serum testosterone concentration and the formation of ovarian cysts, improving the ovulation rate that accompanies lower levels of tyrosine hydroxylase and dopamine ß-hydroxylase in the ovary.


Sujet(s)
Ovulation/effets des médicaments et des substances chimiques , Syndrome des ovaires polykystiques/métabolisme , Propranolol/pharmacologie , Récepteurs bêta-adrénergiques/métabolisme , Antagonistes bêta-adrénergiques/pharmacologie , Animaux , Oestradiol , Oestrus/effets des médicaments et des substances chimiques , Oestrus/physiologie , Femelle , Humains , Ovaire/effets des médicaments et des substances chimiques , Ovaire/métabolisme , Syndrome des ovaires polykystiques/induit chimiquement , Syndrome des ovaires polykystiques/physiopathologie , Rats , Testostérone/sang , Tyrosine 3-monooxygenase/métabolisme
9.
Reprod Biol Endocrinol ; 16(1): 86, 2018 Sep 07.
Article de Anglais | MEDLINE | ID: mdl-30193590

RÉSUMÉ

BACKGROUND: The injection of estradiol valerate in female rats induces polycystic ovary syndrome, which is characterized by polycystic ovaries, anovulation, and hyperandrogenism. These characteristics have been associated with an increase in the ovarian concentration of norepinephrine, which occurs before establishing the polycystic ovary syndrome. The bilateral section of the superior ovarian nerve restores ovarian functions in animals with polycystic ovary syndrome. The superior ovarian nerve provides norepinephrine and vasoactive intestinal peptide to the ovary. An increase in the activity of both neurotransmitters has been associated with the development of polycystic ovary syndrome. The purpose of the present study was analyzed the participation of the noradrenergic nervous system in the development of polycystic ovary syndrome using guanethidine as a pharmacological tool that destroys peripheral noradrenergic nerve fibers. METHODS: Fourteen-day old female rats of the CIIZ-V strain were injected with estradiol valerate or vehicle solution. Rats were randomly allotted to one of three guanethidine treatment groups for denervation: 1) guanethidine treatment at age 7 to 27-days, 2) guanethidine treatment at age 14 to 34- days, and 3) guanethidine treatment at age 70 to 90- days. All animals were sacrificed when presenting vaginal oestrus at age 90 to 94-days. The parameters analyzed were the number of ova shed by ovulating animals, the ovulation rate (i.e., the numbers of ovulating animals/the numbers of used animals), the serum concentration of progesterone, testosterone, oestradiol and the immunoreactivity for tyrosine hydroxylase enzyme. All data were analyzed statistically. A p-value of less than 0.05 was considered significant. RESULTS: Our results show that the elimination of noradrenergic fibers before the establishment of polycystic ovary syndrome prevents two characteristics of the syndrome, blocking of ovulation and hyperandrogenism. We also found that in animals that have already developed polycystic ovary syndrome, sympathetic denervation restores ovulatory capacity, but it was not as efficient in reducing hyperandrogenism. CONCLUSION: The results of the present study suggest that the noradrenergic fibers play a stimulant role in the establishment of polycystic ovary syndrome.


Sujet(s)
Guanéthidine/usage thérapeutique , Syndrome des ovaires polykystiques/anatomopathologie , Neurones adrénergiques/effets des médicaments et des substances chimiques , Animaux , Oestradiol/analogues et dérivés , Femelle , Ovaire/effets des médicaments et des substances chimiques , Ovaire/innervation , Répartition aléatoire , Lignées consanguines de rats , Sympathectomie chimique , Facteurs temps
10.
Oxid Med Cell Longev ; 2018: 1358057, 2018.
Article de Anglais | MEDLINE | ID: mdl-30154946

RÉSUMÉ

An important worldwide health problem as the result of current lifestyle is metabolic syndrome (MS). It has been shown that MS induced by a high-calorie diet (HCD) in rats produces cognitive deterioration in the novel object recognition test (NORt) and decreases synaptic connections and dendritic order in the hippocampus and temporal cortex. However, it is unknown whether MS induced by an HCD participates in the cognitive process observed with the injection of Aß1-42 into the hippocampus of rats as a model of Alzheimer disease (AD). The induction of MS in rats produces a deterioration in NORt; however, rats with MS injected with Aß1-42 show a major deterioration in the cognitive process. This event could be explained by the increment in the oxidative stress in both cases studied (MS and Aß1-42): together, the hippocampus and temporal cortex produce an enhancer effect. In the same way, we observed an increment in interleukin-1ß, TNF-α, and GFAP, indicative of exacerbated inflammatory processes by the combination of MS and Aß1-42. We can conclude that MS might play a key role in the apparition and development of cognitive disorders, including AD. We propose that metabolic theory is important to explain the apparition of cognitive diseases.


Sujet(s)
Peptides bêta-amyloïdes/usage thérapeutique , Inflammation/anatomopathologie , Troubles de la mémoire/étiologie , Syndrome métabolique X/complications , Stress oxydatif/physiologie , Peptides bêta-amyloïdes/pharmacologie , Animaux , Modèles animaux de maladie humaine , Hippocampe/effets des médicaments et des substances chimiques , Mâle , Troubles de la mémoire/anatomopathologie , Rats , Rat Wistar
11.
Synapse ; 71(10): e21987, 2017 Oct.
Article de Anglais | MEDLINE | ID: mdl-28545157

RÉSUMÉ

The aging brain shows biochemical and morphological changes in the dendrites of pyramidal neurons from the limbic system associated with memory loss. Prolame (N-(3-hydroxy-1,3,5 (10)-estratrien-17ß-yl)-3-hydroxypropylamine) is a non-feminizing aminoestrogen with antithrombotic activity that prevents neuronal deterioration, oxidative stress, and neuroinflammation. Our aim was to evaluate the effect of prolame on motor and cognitive processes, as well as its influence on the dendritic morphology of neurons at the CA1, CA3, and granule cells of the dentate gyrus (DG) regions of hippocampus (HP), and medium spiny neurons of the nucleus accumbens (NAcc) of aged mice. Dendritic morphology was assessed with the Golgi-Cox stain procedure followed by Sholl analysis. Prolame (60 µg/kg) was subcutaneously injected daily for 60 days in 18-month-old mice. Immediately after treatment, locomotor activity in a new environment and recognition memory using the Novel Object Recognition Task (NORT) were evaluated. Prolame-treated mice showed a significant increase in the long-term exploration quotient, but locomotor activity was not modified in comparison to control animals. Prolame-treated mice showed a significant increase in dendritic spines density and dendritic length in neurons of the CA1, CA3, and DG regions of the HP, whereas dendrites of neurons in the NAcc remained unmodified. In conclusion, prolame administration promotes hippocampal plasticity processes but not in the NAcc neurons of aged mice, thus improving long-term recognition memory. Prolame could become a pharmacological alternative to prevent or delay the brain aging process, and thus the emergence of neurodegenerative diseases that affect memory.

12.
Oxid Med Cell Longev ; 2016: 8725354, 2016.
Article de Anglais | MEDLINE | ID: mdl-27069534

RÉSUMÉ

Energy drinks (EDs) are often consumed in combination with alcohol because they reduce the depressant effects of alcohol. However, different researches suggest that chronic use of these psychoactive substances in combination with alcohol can trigger an oxidative and inflammatory response. These processes are regulated by both a reactive astrogliosis and an increase of proinflammatory cytokines such as IL-1ß, TNF-α, and iNOS, causing cell death (apoptosis) at the central and peripheral nervous systems. Currently, mechanisms of toxicity caused by mixing alcohol and ED in the brain are not well known. In this study, we evaluated the effect of chronic alcohol consumption in combination with ED on inflammatory response and oxidative stress in the temporal cortex (TCx) and hippocampus (Hp) of adult rats (90 days old). Our results demonstrated that consuming a mixture of alcohol and ED for 60 days induced an increase in reactive gliosis, IL-1ß, TNF-α, iNOS, reactive oxygen species, lipid peroxidation, and nitric oxide, in the TCx and Hp. We also found immunoreactivity to caspase-3 and a decrease of synaptophysin in the same brain regions. The results suggested that chronic consumption of alcohol in combination with ED causes an inflammatory response and oxidative stress, which induced cell death via apoptosis in the TCx and Hp of the adult rats.


Sujet(s)
Boissons énergisantes/effets indésirables , Éthanol/effets indésirables , Hippocampe/anatomopathologie , Inflammation/anatomopathologie , Stress oxydatif , Lobe temporal/anatomopathologie , Animaux , Caspase-3/métabolisme , Cytokines/métabolisme , Éthanol/sang , Protéine gliofibrillaire acide/métabolisme , Médiateurs de l'inflammation/métabolisme , Mâle , Monoxyde d'azote/métabolisme , Nitric oxide synthase type II/métabolisme , Stress oxydatif/effets des médicaments et des substances chimiques , Rat Wistar , Synaptophysine/métabolisme
13.
Mol Pharm ; 12(10): 3724-34, 2015 Oct 05.
Article de Anglais | MEDLINE | ID: mdl-26355665

RÉSUMÉ

Combretastatin A4 disodium phosphate (CA4P) is a fluorescent, water-soluble prodrug able to induce vascular shutdown within tumors at doses less than one-tenth of the maximum tolerated dose. As a continued effort to develop efficient liposomal CA4P to treat solid tumor, we herein investigate the physical and spectroscopic properties of CA4P in aqueous solution and the mechanism of CA4P release from archaeal tetraether liposomes (archaeosomes). We found that cis-CA4P can be photoisomerized to trans-CA4P. This photoisomerization results in an increase in fluorescence intensity. Both cis- and trans-CA4P undergo fluorescence intensity self-quenching after they reach a critical concentration Cq (∼0.15-0.25 mM). Moreover, both cis- and trans-CA4P in buffer exhibit a red shift in their excitation spectrum and an increase in excitation spectrum band sharpness with increasing concentration, which can be attributed to the formation of J-aggregates. The onset of the dramatic change in excitation maximum occurs at concentrations close to Cq, suggesting that the self-quenching arises from extensive J-aggregate formation and that, when CA4P concentration exceeds Cq, J-aggregate formation begins to increase sharply. Our data also suggest that the extent of J-aggregate formation plays a critical role in CA4P release from tetraether archaeosomes and in the subsequent cytotoxicity on cultured human breast cancer MCF-7 cells. The drug leakage and cytotoxicity rate constants vary with the initial CA4P concentration entrapped inside archaeosomes in a biphasic manner, reaching a local maximum at 0.25-0.50 mM. A mechanism based on the concept of J-aggregate formation has been proposed to explain the biphasic changes in drug release and cytotoxicity with increasing drug concentration. Tetraether archaeosomes are extraordinarily stable and relatively nontoxic to animals; thus, they are promising nano drug carriers. The results obtained from this study pave the way for future development of archaeosomal CA4P to treat solid tumors.


Sujet(s)
Antinéoplasiques d'origine végétale/pharmacocinétique , Liposomes/métabolisme , Cellules MCF-7/effets des médicaments et des substances chimiques , Stilbènes/pharmacocinétique , Antinéoplasiques d'origine végétale/pharmacologie , Tumeurs du sein/traitement médicamenteux , Systèmes de délivrance de médicaments/méthodes , Femelle , Colorants fluorescents/métabolisme , Humains , Cellules MCF-7/métabolisme , Stilbènes/pharmacologie
14.
Synapse ; 69(9): 421-33, 2015 Sep.
Article de Anglais | MEDLINE | ID: mdl-26073877

RÉSUMÉ

A high calorie intake can induce the appearance of the metabolic syndrome (MS), which is a serious public health problem because it affects glucose levels and triglycerides in the blood. Recently, it has been suggested that MS can cause complications in the brain, since chronic hyperglycemia and insulin resistance are risk factors for triggering neuronal death by inducing a state of oxidative stress and inflammatory response that affect cognitive processes. This process, however, is not clear. In this study, we evaluated the effect of the consumption of a high-calorie diet (HCD) on both neurodegeneration and spatial memory impairment in rats. Our results demonstrated that HCD (90 day consumption) induces an alteration of the main energy metabolism markers, indicating the development of MS in rats. Moreover, an impairment of spatial memory was observed. Subsequently, the brains of these animals showed activation of an inflammatory response (increase in reactive astrocytes and interleukin1-ß as well as tumor necrosis factor-α) and oxidative stress (reactive oxygen species and lipid peroxidation), causing a reduction in the number of neurons in the temporal cortex and hippocampus. Altogether, these results suggest that a HCD promotes the development of MS and contributes to the development of a neurodegenerative process and cognitive failure. In this regard, it is important to understand the relationship between MS and neuronal damage in order to prevent the onset of neurodegenerative disorders.


Sujet(s)
Régime alimentaire/effets indésirables , Hippocampe/métabolisme , Troubles de la mémoire/métabolisme , Maladies métaboliques/métabolisme , Stress oxydatif/physiologie , Lobe temporal/métabolisme , Animaux , Astrocytes/métabolisme , Astrocytes/anatomopathologie , Protéine gliofibrillaire acide/métabolisme , Hippocampe/anatomopathologie , Interleukine-1 bêta/métabolisme , Peroxydation lipidique/physiologie , Mâle , Troubles de la mémoire/étiologie , Troubles de la mémoire/anatomopathologie , Maladies métaboliques/étiologie , Maladies métaboliques/anatomopathologie , Maladies neurodégénératives/métabolisme , Maladies neurodégénératives/anatomopathologie , Neuro-immunomodulation/physiologie , Rat Wistar , Espèces réactives de l'oxygène/métabolisme , Apprentissage spatial/physiologie , Mémoire spatiale/physiologie , Lobe temporal/anatomopathologie , Facteur de nécrose tumorale alpha/métabolisme
15.
Rev. bras. farmacogn ; 25(2): 145-151, Mar-Apr/2015. graf
Article de Anglais | LILACS | ID: lil-749853

RÉSUMÉ

Abstract Stevia rebaudiana (Bertoni) Bertoni, Asteraceae, is a plant with hypoglycemic and antihyperlipidemic properties. S. rebaudiana (SrB) has become a lead candidate for the treatment of the diabetes mellitus. However, chronic administrations of S. rebaudiana are required to cause the normoglycemic effect. Importantly, nanomaterials in general and titanium dioxide (TiO2) in particular have become effective tools for drug delivery. In this work, we obtained TiO2 nanomaterials with SrB at different concentrations (10, 20 and 30 µM) by sol–gel method. After this nanomaterials were characterized by Fourier transform infrared spectroscopy and transmission electron microscopy. Where it was demonstrated, the presence of the S. rebaudiana in TiO2 nanomaterials, which were observed as hemispherical agglomerated particles of different sizes. The nanomaterials were evaluated in male rats whose diabetes mellitus-phenotype was induced by alloxan (200 mg/kg, i.p.). The co-administration of TiO2-SrB (20 and 30 µM) induced a significant and permanent decrease in the glucose concentration since 4 h, until 30 days post-administration. Likewise, the concentrations of insulin, glycosylated hemoglobin, cholesterol, and triacylglycerides showed a significant recovery to basal levels. The major finding of the study was that the TiO2-SrB (20 and 30 µM) has a potent and prolonged activity antidiabetic. TiO2 can be considered like an appropriated vehicle in the continuous freeing of active substances to treat of diabetes mellitus.

16.
Rev. bras. farmacogn ; 24(4): 419-424, Jul-Aug/2014. graf
Article de Anglais | LILACS | ID: lil-725632

RÉSUMÉ

Diarrhea is a serious public health problem in Mexico and other countries. A widely used alternative in the treatment of diarrhea is the use of herbal medicines. Infusions of chamomile and star anise possess anti-inflammatory and antimotility properties that could help alleviate gastrointestinal disorders. The aim of this study was to determine the effect of the mixture of chamomile and star anise infusions on gastrointestinal activity in mice. A gastrointestinal assessment of the mixture of chamomile and star anise was carried out in mice, and the percentage of advance of administered activated carbon through the intestinal tract of the animals was measured. Furthermore, the diarrhea model was induced with castor oil. The infusions were prepared using a mix with a 50:50 ratio of the herbs, and were administered at Mix-10, 20, 40 and 80 (mg/kg) orally. The results indicate that Mix-40 and Mix-80 decreased the completion percentage of the activated carbon, delayed the appearance of diarrhea and decreased the number of evacuations in comparison with the control group. This suggests that the combination of chamomile and star anise can be used as an alternative antidiarrheal treatment.

17.
Biophys J ; 102(9): 2086-94, 2012 May 02.
Article de Anglais | MEDLINE | ID: mdl-22824272

RÉSUMÉ

Liposomal drugs are a useful alternative to conventional drugs and hold great promise for targeted delivery in the treatment of many diseases. Most of the liposomal drugs on the market or under clinical trials include cholesterol as a membrane stabilizing agent. Here, we used liposomal CA4P, an antivascular drug, to demonstrate that cholesterol content can actually modulate the release and cytotoxicity of liposomal drugs in a delicate and predictable manner. We found that both the rate of the CA4P release from the interior aqueous compartment of the liposomes to the bulk aqueous phase and the extent of the drug's cytotoxicity undergo a biphasic variation, as large as 50%, with liposomal cholesterol content at the theoretically predicted C(r), e.g., 22.0, 22.2, 25.0, 33.3, 40.0, and 50.0 mol % cholesterol for maximal superlattice formation. It appears that at C(r), CA4P can be released from the liposomes more readily than at non-C(r), probably due to the increased domain boundaries between superlattice and nonsuperlattice regions, which consequently results in increased cytotoxicity. The idea that the increased domain boundaries at C(r) would facilitate the escape of molecules from membranes was further supported by the data of dehydroergosterol transfer from liposomes to MßCD. These results together show that the functional importance of sterol superlattice formation in liposomes can be propagated to distal targeted cells and reveal a new, to our knowledge, mechanism for how sterol content and membrane lateral organization can control the release of entrapped or embedded molecules in membranes.


Sujet(s)
Tumeurs du sein/anatomopathologie , Tumeurs du sein/physiopathologie , Préparations à action retardée/composition chimique , Liposomes/composition chimique , Stilbènes/administration et posologie , Stilbènes/composition chimique , Antinéoplasiques d'origine végétale/administration et posologie , Antinéoplasiques d'origine végétale/composition chimique , Tumeurs du sein/traitement médicamenteux , Lignée cellulaire tumorale , Survie cellulaire , Diffusion , Préparation de médicament/méthodes , Femelle , Humains
18.
Neurosci Res ; 65(1): 98-106, 2009 Sep.
Article de Anglais | MEDLINE | ID: mdl-19523997

RÉSUMÉ

Recently it has been shown that the C-terminus fragment of the tetanus toxin (Hc-TeTx) is transported retrogradely and had shown neuroprotective effects, preventing neuronal death by apoptosis. This could be a new alternative preventing ongoing cell death and restoring the motor function in Parkinson's disease (PD), which is characterized by dopaminergic neurodegeneration. Our aim was to evaluate the effects of local administration of Hc-TeTx on motor behavior and the dopamine (DA) levels in the striatum of MPP(+)-treated rats. In the rotational behavior task, the Hc-TeTx [2 microM]+MPP(+) group had a decreased number of contralateral rotations and the cylinder test improved for both forelimb-use asymmetry compared to the MPP(+) group. The staircase test showed that the Hc-TeTx+MPP(+) group had an improvement of fine motor skills compared to the same limb performance of the MPP(+) group. The group of animals with Hc-TeTx+MPP(+) had higher DA and metabolite levels compared to the MPP(+) group. Our study clearly shows that Hc-TeTx improves different motor behavior strongly, which favors the hypothesis of the Hc-TeTx fragment enhancing survival pathways that result in amelioration of the dopaminergic system of rats with a dopaminergic lesion.


Sujet(s)
Intoxication au MPTP/traitement médicamenteux , Activité motrice/effets des médicaments et des substances chimiques , Fragments peptidiques/usage thérapeutique , Toxine tétanique/usage thérapeutique , 1-Méthyl-4-phényl-pyridinium/pharmacologie , Animaux , Corps strié/effets des médicaments et des substances chimiques , Corps strié/anatomopathologie , Corps strié/physiopathologie , Dopamine/métabolisme , Intoxication au MPTP/anatomopathologie , Intoxication au MPTP/physiopathologie , Mâle , Dégénérescence nerveuse/métabolisme , Dégénérescence nerveuse/anatomopathologie , Dégénérescence nerveuse/physiopathologie , Neurones/métabolisme , Rats , Rat Wistar
19.
Chem Phys Lipids ; 159(2): 95-103, 2009 Jun.
Article de Anglais | MEDLINE | ID: mdl-19477316

RÉSUMÉ

The stability of liposomes made of the polar lipid fraction E (PLFE) isolated from the thermoacidophilic archaeon Sulfolobus acidocaldarius against autoclaving has been studied by using dynamic light scattering and transmission electron microscopy. PLFE lipids have structures distinctly different from those derived from eukaryotes and prokaryotes. PLFE lipids are bipolar tetraether molecules and may contain up to four cyclopentane rings in each of the two dibiphytanyl chains. In the pH range 4-10, PLFE-based archaeosomes, with and without polyethyleneglycol- and maleimide-lipids, are able to retain vesicle size, size distribution, and morphology through at least six autoclaving cycles. The cell growth temperature (65 degrees C vs. 78 degrees C), hence the number of cyclopentane rings in the hydrocarbon chains, does not affect this general conclusion. By contrast, at the same pH range, most conventional liposomes made of monopolar diester lipids and cholesterol or pegylated lipids cannot withhold vesicle size and size distribution against just one cycle of autoclaving. At pH<4, the particle size and polydispersity of PLFE-based archaeosomes increase with autoclaving cycles, suggesting that aggregation or membrane disruption may have occurred at extreme acidic conditions during heat sterilization. Under high salt conditions, dye leakage from PLFE archaeosomes due to autoclaving is significantly less than that from pegylated liposomes composed of conventional lipids. The ability to maintain vesicle integrity after multiple autoclaving cycles indicates the potential usefulness of utilizing PLFE-based archaeosomes as autoclavable and durable drug (including genes, peptides, vaccines, siRNA) delivery vehicles.


Sujet(s)
Température élevée , Liposomes/composition chimique , Stabilité de médicament , Concentration en ions d'hydrogène , Microscopie électronique en transmission à balayage , Taille de particule , Diffusion de rayonnements , Sulfolobus acidocaldarius/composition chimique
20.
Pharm Res ; 26(5): 1093-100, 2009 May.
Article de Anglais | MEDLINE | ID: mdl-19172383

RÉSUMÉ

PURPOSE: Radiation upregulates expression of endothelial cell adhesion molecules providing a potential avenue for targeting drugs to irradiated tissue. Induced upregulation of E-selectin can be used to target immunoliposomes to solid tumors. The effects of targeting immunoliposomes containing the antivascular drug combretastatin disodium phosphate (CA4P) to irradiated mammary tumors were investigated in this study. METHODS: Mice bearing transplanted MCa-4 mouse mammary tumors were assigned to one of the factorial treatments permuting the administration of free CA4P, tumor irradiation, CA4P encapsulated liposomes, and CA4P encapsulated immunoliposomes (conjugated with anti-E-selectin). Single and fractionated dosing of radiation and/or CA4P was evaluated. RESULTS: For single dose treatments the group that received a single dose of radiation plus a single dose of immunoliposomes showed a significant delay in tumor growth compared to all other treatment groups. Fractionated radiation plus fractionated doses of immunoliposomes resulted in further tumor growth delay; however, it was not significantly different from other fractionated dose treatment groups that combined radiation and CA4P. CONCLUSIONS: Targeting of antivascular drugs to irradiated tumors via ligand-bearing liposomes results in significant tumor growth delay. This effect can be further potentiated using a fractionated irradiation dosing schedule combined with fractionated immunoliposome treatments.


Sujet(s)
Antinéoplasiques d'origine végétale/administration et posologie , Bibenzyles/administration et posologie , Tumeurs du sein/traitement médicamenteux , Systèmes de délivrance de médicaments , Sélectine E/immunologie , Liposomes/immunologie , Animaux , Antinéoplasiques d'origine végétale/usage thérapeutique , Bibenzyles/usage thérapeutique , Tumeurs du sein/vascularisation , Tumeurs du sein/génétique , Tumeurs du sein/radiothérapie , Sélectine E/génétique , Femelle , Liposomes/pharmacocinétique , Souris , Souris de lignée C3H , Transplantation tumorale , Rayonnement , Régulation positive
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