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1.
Domest Anim Endocrinol ; 65: 56-66, 2018 10.
Article in English | MEDLINE | ID: mdl-29909240

ABSTRACT

Nesfatin-1 is a naturally occurring 82-amino acid protein encoded in the precursor nucleobindin-2 (NUCB2) and has been implicated in multiple physiological functions, including food intake and blood glucose regulation. This study aimed to characterize nesfatin-1 in domestic species, especially cats (Felis catus), dogs (Canis lupus familiaris), and pigs (Sus scrofa). Our in silico analysis demonstrated that the NUCB2/nesfatin-1 amino acid sequence, especially the bioactive core region of the peptide, is very highly conserved (more than 90% identity) in domestic animals. Expression of mRNAs encoding NUCB2/nesfatin-1 was detected in the cat, dog, and pig stomach and pancreas. Immunohistochemistry revealed the presence of nesfatin-1 in the gastric mucosa of the stomach of dogs, cats, and pigs, and in the pancreatic islet ß-cells of dogs and pigs. No nesfatin-1 immunoreactivity was found in the cat pancreas. Nesfatin-1 was detected in the serum of dog, cat, pig, bison, cow, horse, sheep, and chicken. Circulating nesfatin-1 in male and female dogs remained unchanged at 60 min after glucose administration, suggesting a lack of meal responsiveness in nesfatin-1 secretion in this species. The presence of nesfatin-1 in the gastric and endocrine pancreatic tissues suggests possible roles for this peptide in the metabolism of domestic animals. Future research should focus on elucidating the species-specific functions and mechanisms of action of nesfatin-1 in health and disease of domestic animals.


Subject(s)
Animals, Domestic/blood , Calcium-Binding Proteins/analysis , Calcium-Binding Proteins/blood , DNA-Binding Proteins/analysis , DNA-Binding Proteins/blood , Nerve Tissue Proteins/analysis , Nerve Tissue Proteins/blood , Amino Acid Sequence , Animals , Bison , Calcium-Binding Proteins/genetics , Cats , Cattle , Chickens , Conserved Sequence , DNA-Binding Proteins/genetics , Dogs , Female , Gastric Mucosa/chemistry , Horses , Immunohistochemistry , Islets of Langerhans/chemistry , Male , Nerve Tissue Proteins/genetics , Nucleobindins , Organ Specificity , RNA, Messenger/analysis , Sheep , Sus scrofa
2.
J Comp Physiol B ; 186(6): 727-38, 2016 08.
Article in English | MEDLINE | ID: mdl-27062032

ABSTRACT

The periprandial profile and effects of short- (7 days) and long-term (30 days) fasting on the ghrelinergic system were studied in goldfish (Carassius auratus). Plasma levels of acyl-ghrelin, desacyl-ghrelin, and ghrelin O-acyl transferase (GOAT) were analyzed by enzymoimmunoassays, and expression of preproghrelin, goat and growth hormone secretagogue receptors (ghs-r) was quantified by real-time PCR. Circulating levels of acyl-ghrelin and GOAT rise preprandially, supporting the role of acyl-ghrelin as a meal initiator in this teleost. Consistently, preproghrelin and ghs-r1a1 expression increases 1 h before feeding time in intestinal bulb, suggesting that this receptor subtype might be involved in the preprandial action of ghrelin in this tissue. Significant postfeeding variations are detected for preproghrelin in telencephalon, goat in telencephalon and hypothalamus, ghs-r1a1 in vagal lobe, ghs-r1a2 and ghs-r2a1 in hypothalamus and ghs-r2a2 in telencephalon and vagal lobe, especially in unfed fish. Short- and long-term fasting significantly increase preproghrelin expression in telencephalon and gut. Goat expression is upregulated by short-term fasting in telencephalon and hypothalamus, and by both short- and long-term fasting in gut. Expression of ghs-r increases by fasting in telencephalon, while an upregulation of type 2, but not type 1, receptors is observed in vagal lobe. In intestinal bulb, ghs-r1a2 transcripts increase after both short- and long-term fasting. These results show a high dependence of the ghrelinergic system on feeding and nutritional status in fish, and demonstrate for the first time a differential implication of the various components of this system suggesting different roles for the four ghrelinergic receptor subtypes.


Subject(s)
Acyltransferases , Eating/physiology , Fasting/metabolism , Fish Proteins , Ghrelin , Goldfish/metabolism , Receptors, Ghrelin , Acyltransferases/blood , Acyltransferases/genetics , Animals , Brain/metabolism , Fish Proteins/blood , Fish Proteins/genetics , Ghrelin/blood , Ghrelin/genetics , Goldfish/blood , Goldfish/genetics , Intestinal Mucosa/metabolism , RNA, Messenger/metabolism , Receptors, Ghrelin/genetics
3.
Article in English | MEDLINE | ID: mdl-26051613

ABSTRACT

Cholecystokinin (CCK) plays a key role in the digestive physiology of vertebrates. However, very little is known about the role of CCK on intestinal functions in fish. The present study identifies two CCK receptor subtypes in a stomachless teleost, the goldfish (Carassius auratus), and investigates by using an in vitro system their involvement mediating the effects of the sulfated octapeptide of CCK (CCK-8S) on the motility of isolated proximal intestine. Partial-length mRNAs encoding two CCK receptor isoforms (CCKAR and CCKBR.I) were sequenced and the structural analysis showed that both receptors belong to the G-protein coupled receptor superfamily. Both goldfish CCK receptor sequences were more closely related to zebrafish sequences, sharing the lowest similarities with cavefish and tilapia. The highest expression of goldfish CCKAR was observed along the whole intestine whereas the CCKBR gen was predominantly expressed in the hypothalamus, vagal lobe and posterior intestine. Application of CCK-8S to the organ bath evoked a concentration-dependent contractile response in intestine strips. The contractions were not blocked by either tetrodotoxin or atropine, suggesting that CCK-8S acts on the gut smooth muscle directly. Preincubations of intestine strips with devazepide and L365,260 (CCKAR and CCKBR receptor selective antagonists) showed that the CCK-8S-induced contraction could be partially mediated by the CCKAR receptor subtype, which is also the most abundant CCK receptor found in gastrointestinal tissues. In conclusion, two CCK receptors with a differential distribution pattern has been identified in goldfish, and the CCKAR subtype is mainly involved in the regulation of intestinal motility by the CCK-8S.


Subject(s)
Gastrointestinal Motility/physiology , Goldfish/physiology , Protein Isoforms/pharmacology , Receptors, Cholecystokinin/physiology , Animals , Protein Isoforms/chemistry , Receptors, Cholecystokinin/chemistry
4.
Article in English | MEDLINE | ID: mdl-25956213

ABSTRACT

Brain glycogen is depleted when used as an emergency energy substrate. In mammals, brain glycogen levels rebound to higher than normal levels after a hypoglycemic episode and a few hours after refeeding or administration of glucose. This phenomenon is called glycogen supercompensation. However, this mechanism has not been investigated in lower vertebrates. The aim of this study was therefore to determine whether brain glycogen supercompensation occurs in the rainbow trout brain. For this purpose, short-term brain glucose and glycogen contents were determined in rainbow trout after being subjected to the following experimental conditions: i) a 5-day or 10-day fasting period and refeeding; ii) a single injection of insulin (4 mg kg(-1)) and refeeding; and iii) sustained swimming and injection of glucose (500 mg kg(-1)). Food deprivation during the fasting periods and insulin administration both induced a decrease in glucose and glycogen levels in the brain. However, only refeeding after 10 days of fasting significantly increased the brain glycogen content above control levels, in a clear short-term supercompensation response. Unlike in mammals, prolonged exercise did not alter brain glucose or glycogen levels. Furthermore, brain glycogen supercompensation was not observed after glucose administration in fish undergoing sustained swimming. To our knowledge, this is the first study providing direct experimental evidence for the existence of a short-term glycogen supercompensation response in a teleost brain, although the response was only detectable after prolonged fasting.


Subject(s)
Brain/metabolism , Glycogen/metabolism , Hypoglycemia/metabolism , Oncorhynchus mykiss/physiology , Swimming , Animals , Feeding Behavior , Hypoglycemia/chemically induced , Hypoglycemia/physiopathology , Insulin/administration & dosage
7.
Cytopathology ; 18(1): 33-9, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17250601

ABSTRACT

OBJECTIVE: The objective of this study was to establish the value of different markers in differentiating reactive mesothelial cells from metastatic adenocarcinomatous cells in serous effusions (SE). METHODS: Forty-five SE were processed for morphological examination (Papanicolaou stain), assessment of ploidy, AgNOR counting and immunocytochemical assay of carcinoembryonic antigen (CEA), epithelial membrane antigens (EMA), Ber-EP4 and Leu-M1. Ploidy was established in an image-analyser in smears stained by the Feulgen stain method. AgNOR dots were counted in the smears stained with the silver nitrate assay for non-histone proteins present in the nucleolar organizer region. CEA, EMA, Ber-EP4 and Leu-M1 were evaluated by immunocytochemistry using the streptavidin-biotin complex method. RESULTS: All the smears with positive cytology were aneuploid. Three false negatives by morphological studies were aneuploid, with AgNOR values in two of them corresponding to the neoplastic group. CEA and Leu-M1 showed a low specificity; EMA and Ber-EP4 showed moderate sensitivity. CONCLUSIONS: The assessment of ploidy and the study of AgNOR were better methods than immunocytochemistry for distinguishing between reactive mesothelial cells and adenocarcinomatous cells in serous fluid.


Subject(s)
Adenocarcinoma/pathology , Antigens, Nuclear/metabolism , Ascitic Fluid/cytology , Neoplasms/pathology , Nuclear Proteins/metabolism , Pleural Effusion/cytology , Adenocarcinoma/genetics , Adenocarcinoma/metabolism , Ascitic Fluid/metabolism , Epithelial Cells/metabolism , Epithelial Cells/pathology , Humans , Immunohistochemistry/methods , Neoplasms/genetics , Neoplasms/metabolism , Pleural Effusion/genetics , Pleural Effusion/metabolism , Ploidies , Vaginal Smears/methods
8.
Inmunología (1987) ; 25(3): 188-200, jul.-sept. 2006. ilus
Article in Es | IBECS | ID: ibc-054768

ABSTRACT

La expresión de mediadores inflamatorios y citocinas están implicadas en la patogénesis de diversas enfermedades neurodegenerativas. Una característica importante de la neuroinflamación es la activación de las células gliales, especialmente microglia y astroglia, que producen citocinas, compuestos pro-inflamatorios y tóxicos, desencadenando una respuesta inflamatoria y daño cerebral. Estudios recientes sugieren que los receptores TLRs (Toll-like), junto a las células gliales desempeñan un papel relevante en la respuesta inmune del sistema nervioso central (SNC), y una alteración en la regulación de dicha respuesta puede causar neurodegeneración. El abuso de alcohol y el alcoholismo inducen daño cerebral y, en algunos casos causan neurodegeneración. Los procesos neuropatológicos implicados en estos efectos no están totalmente esclarecidos. Evidencias recientes sugieren que el etanol es capaz de activar a las células gliales y de inducir procesos inflamatorios en el cerebro que pueden conducir a muerte neural. Estas evidencias demuestran que el etanol favorece la activación de vías de señalización intracelular (IKK, MAPKs) y factores de transcripción (NF-κB, AP-1) que conllevan a la producción de citocinas y de mediadores inflamatorios (iNOS, NO, COX-2) en cerebro y en células astrogliales. La respuesta inflamatoria inducida por el etanol parece estar mediada por una activación de los receptores TLR4/IL-1RI, ya que cuando se bloquea su función, se eliminan los efectos del etanol sobre la inducción de mediadores inflamatorios y muerte celular. Aunque los mecanismos que subyacen a la activación de estos receptores se desconoce, proponemos que el etanol a través de su interacción con los lípidos de membrana, podría facilitar el reclutamiento de los receptores TLR4 e IL-1RI en los microdominios de membrana (lipid rafts), conllevando a un aumento en su respuesta y señalización. En conclusión, aunque se requieren más trabajos para evaluar el mecanismo de la activación de los TLR4/IL-1RI por el etanol, en esta revisión se presentan estudios que apoyan la idea de que un aumento en la respuesta innata inmune a través de los receptores TLR4/IL-1RI, podría participar en el daño cerebral asociado al consumo de alcohol


Inflammatory mediators and cytokine expression are implicated in the pathogenesis of several neurodegenerative diseases. The hallmark of brain inflammation is the activation of glial cells, especially microglia and astroglia, which produce a variety of pro-inflammatory and toxic compounds that can induce brain damage. Recent developments in our understanding of neurodegeneration implicate glial cells and Toll-like receptors (TLRs) as vital players in the immune response within the central nervous system, and that deregulation of this response plays an important role in brain injury and neurodegeneration. Alcohol abuse and alcoholism induce brain damage, and in some cases, neurodegeneration. The neuropathologic processes underlying these effects remain poorly understood. Recent data demonstrate that ethanol promotes inflammatory processes in the brain and in glial cells by upregulating cytokines and inflammatory mediators (iNOS, NO, COX-2), and by activating signalling pathways (IKK, MAPKs) and transcriptional factors (NF-κB, AP-1) implicated in inflammatory injury. TLR4 and IL-1RI are involved in the signalling of ethanol-induced inflammatory response, since blocking these receptors abolishes the production of ethanolinduced inflammatory mediators and cell death in astrocytes. Although the mechanisms involved in the ethanol-induced activation of TLR4/IL-1RI receptors are unknown, we propose that ethanol can facilitate TLR4/IL- 1RI recruitment into lipid raft microdomains through its interaction with membrane lipids, leading to the activation and signalling of these receptors. In summary, although further work is needed to evaluate this hypothesis, this review presents evidences supporting the notion that the activation of innate immune system and TLR4/IL-1RI by ethanol triggers inflammatory mediators in the brain and causes brain damage


Subject(s)
Humans , Alcoholism/immunology , Astrocytes/immunology , Encephalitis/immunology , Encephalitis/etiology , Immune System/immunology , Immune System , Ethanol/immunology , Ethanol/pharmacology , Inflammation Mediators/immunology
12.
Arch Androl ; 49(5): 343-9, 2003.
Article in English | MEDLINE | ID: mdl-12893510

ABSTRACT

Spermatozoa travel a long distance to meet and fertilize the oocyte, so sperm motility is a requisite for normal fertilization. Asthenozoospermia, or low sperm motility, is a common cause of human male infertility. This is a retrospective study (1992-1999) to document the prevalence of this pathology in infertile men and to clarify the probable factors associated to its etiology. The prevalence was 18.71% for asthenozoospermia and 63.13% for asthenozoospermia associated with oligo- and/or teratozoo-spermia; thus, 81.84% of the studied samples had altered motility. Leukocytospermia, the ratio of germ cells/sperm, anti-sperm antibodies, consistency, biochemical markers of accessory sex glands, and sperm response after swim-up were studied in normospermic (N), asthenozoospermic (A), and combined asthenozoospermic (C) samples. No significant difference was found in the frequency of leukocytospermia among groups. The rate of germ cells/(spermatozoa + germ cells) between C and N (p < .01) and C and A (p < .01) was statistically different, while no difference was found on comparing N and A. MAR-test over 40% was found in 6% of the A samples and 7.6% of the C, while no positive values were observed in the N group. The percentage of hyperviscous samples was higher in the low sperm motility samples than in the normal group. Data on concentration of the biochemical markers seem to be decreased in asthenozoospermia. Pure and combined asthenozoo-spermia showed different behavior in sperm recovery after swim-up. Two different asthenozoospermias could be defined: the pure one where sperm environment is involved (immunological factor, hyperviscosity, and secretory gland function) and the combined, where the testis is comprised.


Subject(s)
Oligospermia , Sperm Maturation/physiology , Sperm Motility/physiology , Spermatozoa/pathology , Acid Phosphatase , Antibodies/immunology , Argentina/epidemiology , Citric Acid/analysis , Fructose/analysis , Humans , Leukocyte Count , Leukocytosis/complications , Leukocytosis/physiopathology , Male , Oligospermia/epidemiology , Oligospermia/etiology , Oligospermia/physiopathology , Protein Tyrosine Phosphatases/analysis , Retrospective Studies , Semen/chemistry , Spermatozoa/immunology
16.
Arch Androl ; 49(4): 247-55, 2003.
Article in English | MEDLINE | ID: mdl-12851026

ABSTRACT

The purpose of this research was to investigate, using light, transmission, and scanning electron microscope, the effect of hypothyroidism on the ultrastructure of the rat epididymis. Thyroidectomy was obtained by ip injection of 270 microCi of (131)I per rat. One month later, several portions of cauda epididymis were examined. Morphological differences were detected in the epididymis of the hypothyroid animals when compared to the control normal rats. The hypothyroid conditions were associated with important changes in the epididymis. The light observations showed cells with clearing of the chromatin and increased density and thickness of the chromatic rim, chromatinic net, and disappearance of the segment of the chromatin rim. In the scanning electron microscope broken, oblique, denuded epithelial cells with loss of stereocilia were observed, as well as flattening of the tubule. The hypothyroid condition under transmission electron microscope was associated with a decrease in the height of the cells, diminution of the internal lumen and number of mitoses, and decreased chromatin decondensation. Results obtained confirmed that hypothyroidism causes marked structural changes in the ductus epididymis and could adversely affect the maturation and motility of sperm.


Subject(s)
Epididymis/ultrastructure , Hypothyroidism/pathology , Animals , Hypothyroidism/complications , Male , Microscopy, Electron, Scanning , Rats , Rats, Wistar , Thyroidectomy
19.
Arch Androl ; 48(2): 127-31, 2002.
Article in English | MEDLINE | ID: mdl-11868625

ABSTRACT

The immature germ cells (IGC) constitute the highest percentage (90%) of nonsperm cells (NSpC) in ejaculates from fertile or infertile men. The objective of this study was to evaluate IGC concentration and the IGC/(IGC + Sp) ratio, in normozoospermia and dispermia. Normozoospermia from men with proven fertility (NPF). nonproven fertility (NNPF). dispermia (D) and semen samples with excessive shedding of immature germ cells (GI 1.7 x 10(6) to 5 x 10(6) IGC/mL and GII > 5.0 x 10(6) IGC/mL) were used in this study. The mean value +2 SD for the NNPF (1.7 x 10(6)/mL) and the value proposed by WHO (5 x 10(6)/mL) were employed to define GI and GII groups. IGC concentration is statistically different in the studied groups. The IGC/Sp ratio showed a significant difference only between the NNPF and the D. When comparing semen parameters (Sp/ejaculate. grade (a) motility and morphology) there was a highly significant difference between NNPF and GI and GII: no difference was found between GI and GII. While studying 200 cases of dispermias 83% showed a high shedding of immature germ cells. The cytological study of nonsperm cells and the count and identification of the immature germ cells could be used to evaluate the dispermic disorders.


Subject(s)
Sperm Motility/physiology , Spermatozoa/cytology , Ejaculation , Humans , Male , Oligospermia/physiopathology , Reference Values
20.
Arch Androl ; 46(1): 73-7, 2001.
Article in English | MEDLINE | ID: mdl-11204621

ABSTRACT

The purpose of this research was to investigate, using scanning electron microscopy, the effect of hypothyroidism on the ultrastructure of the rat cauda epididymis. Thyroidectomy was obtained by ip injection of 270 muCi of 131I per rat. One month later, several portions of cauda epididymis were examined. Morphological and physiological differences were detected in the cauda epididymis of the hypothyroid animals when compared to the control normal rats. The hypothyroid condition was associated with important changes in the luminal surface of the cauda epididymis epithelium. Broken, oblique, and loss of stereocilia, denuded epithelial cells, and flattening of the tubule were observed. The results confirm that hypothyroidism causes marked structural changes in the cauda ductus epididymis and could be adversely affect sperm maturation motility.


Subject(s)
Epididymis/ultrastructure , Hypothyroidism/pathology , Animals , Male , Mice , Microscopy, Electron, Scanning , Rats , Rats, Wistar , Thyroidectomy
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