Histology and histopathology Vol.27, nº11 (2012)

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  • Publication
    Open Access
    Regulation of neuronal and endothelial nitric oxide synthase by anabolic-androgenic steroid in skeletal muscles
    (F. Hernández y Juan F. Madrid. Universidad de Murcia. Departamento de Biología Celular e Histología, 2012) Fontana, Karina; Rocha, Thalita; da Cruz-Höfling, Maria Alice
    Anabolic-androgenic steroids (AAS) and exercise share comparable effects on myogenic differentiation, force development, fiber growth and skeletal muscle plasticity. The participation of nitric oxide synthase (NOS) on these effects was only demonstrated in response to exercise. Using immunohistochemistry and western blotting we examined the effect of AAS on the expression of NOS I and III isoforms in three muscles, distinct metabolically and physiologically: soleus (SOL), tibialis anterioris (TA) and gastrocnemius (GAS). Mice with a lipid profile akin to humans were used. Sedentary mice (Sed-C) or exercised, submitted to six-weeks of aerobic treadmill running (one hour/day, 5 days/week) were administered mesterolone (Sed-M and Ex-M, respectively) or gum arabic (vehicle, Ex-C) during the last three weeks, three alternate days per week. Consistently, The TA showed the strongest labeling and the SOL the weakest with NOS III predominating over NOS I. Mesterolone administered to sedentary mice (Sed-C x Sed-M) significantly upregulated NOS I in TA and SOL and NOS III in all three muscles. Mesterolone administered to exercised mice (Ex-C x Ex-M) upregulated NOS I in all three muscles and NOS III in TA and SOL. The exercise to mesterolone-treated mice (Sed-M x Ex-M) produced a strong increase in NOS I expression in GAS; in contrast it antagonized the mesterolone-induced upregulation of NOS I in TA muscle and NOS III in SOL and GAS. The data show nitric oxide (NO) as a potential signaling mediator of AAS effects in skeletal muscle and that NOS I and NOS III upregulations were muscle phenotype-specific. These may be regarded as an indication of the complex NOS/NO signaling mechanism related with AAS effects vs. metabolic/physiological muscle characteristics.
  • Publication
    Open Access
    Experimental diabetes modulates collagen remodelling of joints in rats
    (F. Hernández y Juan F. Madrid. Universidad de Murcia. Departamento de Biología Celular e Histología, 2012) Atayde, Sandra A.; Yoshinari, Natalino H.; Nascimento, Dafne P.; Catanozi, Sérgio; Andrade, Priscila C.; Velosa, Ana Paula P.; R. Parra, Edwin; Passarelli, Marisa; Nakandakare, Edna R.; Capelozzi, Vera L.; Teodoro, Walcy R.
    The aim of this study was to evaluate extracellular matrix components in articular cartilage, ligaments and synovia in an experimental model of diabetes. Young Wistar rats were divided into a streptozotocin-induced (STZ; 35 mg/kg) diabetic group (DG; n=15) and a control group (CG; n=15). Weight, blood glucose and plasma anti-carboxymethyllysine were measured 70 days after STZ infusions. Knee joints, patellar ligaments, and lateral and medial collateral ligaments were isolated and stained with hematoxylin-eosin and Picrosirius. The total collagen content was determined by morphometry. Immunofluorescence was employed to evaluate types I, III, and V collagen in ligaments and synovial tissues and types II and XI collagen in cartilage. Results: Higher blood glucose levels and plasma anti-carboxymethyllysine were observed in DG rats when compared to those in CG rats. The final weight was significantly lower in the DG rats than in the CG rats. Histomorphometric evaluation depicted a small quantity of collagen fibers in ligaments and articular cartilage in DG rats, as well as increased collagen in synovial tissue. There was a decrease in cartilage proteoglycans in DG rats when compared with CG rats. Immunofluorescence staining revealed an increase of collagen III and V in ligaments, collagen XI in cartilage, and collagen I in synovial tissue of DG rats compared with CG rats. Conclusion: The ligaments, cartilage and synovia are highly affected following STZ-induced diabetes in rats, due the remodeling of collagen types in these tissues. This process may promote the degradation of the extracellular matrix, thus compromising joint function. Our data may help to better understand the pathogenesis of joint involvement related to diabetes.
  • Publication
    Open Access
    Angiotensinergic innervation of the kidney: Localization and relationship with catecholaminergic postganglionic and sensory nerve fibers
    (F. Hernández y Juan F. Madrid. Universidad de Murcia. Departamento de Biología Celular e Histología, 2012) Bohlender, Jürgen; Pfarrer, Beat; Patil, Jaspal; Nussberger, Jürg; Thalmann, Georg N. Thalmann; Imboden, Hans
    We describe an angiotensin (Ang) II-containing innervation of the kidney. Cryosections of rat, pig and human kidneys were investigated for the presence of Ang II-containing nerve fibers using a mouse monoclonal antibody against Ang II (4B3). Co-staining was performed with antibodies against synaptophysin, tyrosine 3-hydroxylase, and dopamine beta-hydroxylase to detect catecholaminergic efferent fibers and against calcitonin gene-related peptide to detect sensory fibers. Tagged secondary antibodies and confocal light or laser scanning microscopy were used for immunofluorescence detection. Ang II-containing nerve fibers were densely present in the renal pelvis, the subepithelial layer of the urothelium, the arterial nervous plexus, and the peritubular interstitium of the cortex and outer medulla. They were infrequent in central veins and the renal capsule and absent within glomeruli and the renal papilla. Ang II-positive fibers represented phenotypic subgroups of catecholaminergic postganglionic or sensory fibers with different morphology and intrarenal distribution compared to their Ang II-negative counterparts. The Ang II-positive postganglionic fibers were thicker, produced typically fusiform varicosities and preferentially innervated the outer medulla and periglomerular arterioles. Ang II-negative sensory fibers were highly varicose, prevailing in the pelvis and scarce in the renal periphery compared to the rarely varicose Ang II-positive fibers. Neurons within renal microganglia displayed angiotensinergic, cate-cholaminergic, or combined phenotypes. Our results suggest that autonomic fibers may be an independent source of intrarenal Ang II acting as a neuropeptide co-transmitter or neuromodulator. The angiotensinergic renal innervation may play a distinct role in the neuronal control of renal sodium reabsorption, vasomotion and renin secretion.
  • Publication
    Open Access
    Clinicopathologic features of molecular subtypes of triple negative breast cancer based on immunohistochemical markers
    (F. Hernández y Juan F. Madrid. Universidad de Murcia. Departamento de Biología Celular e Histología, 2012) Choi, Junjeong; Jung, Woo-Hee; Koo, Ja Seung
    This study was performed to identify molecular subtypes of triple negative breast carcinoma (TNBC) based on immunohistochemical markers. We prepared a tissue microarray from TNBC specimens of 122 patients and performed immunohistochemical staining for cytokeratin (CK) 5/6, epidermal growth factor receptor (EGFR), claudin 3, claudin 4, claudin 7, E-cadherin, androgen receptor (AR), and gammma-glutamyltransferase (GGT1). Based on immunoreactivity, tumors were classified into basal-like (CK5/6 positive and/or EGFR positive), molecular apocrine (AR positive and/or GGT1 positive), claudin low (claudin 3, claudin 4, claudin 7 negative and/or E-cadherin negative), mixed (tumors belonging to two or more subtypes), and null (tumors not matching any other subtypes). The TNBC specimens of 122 patients included 27 basal-like (22.1%), 28 claudin low (23.0%), 12 molecular apocrine (9.8%), 23 mixed (18.9%) and 32 null (26.2%) subtype tumors. The molecular apocrine subtype showed the highest percentage of apocrine differentiation and the lowest Ki-67 labeling index (p<0.001 and p=0.040, respectively). In univariate analysis, tumor cell discohesiveness was related with shorter disease free survival (DFS) and overall survival (OS) (p=0.005, and 0.002, respectively). In multivariate analysis, tumor cell discohesiveness was related with shorter OS and CK5/6 positivity (p=0.018), and claudin 7 positivity (p=0.019) was related with shorter DFS. In conclusion, using immunohistochemical staining for CK5/6, EGFR, claudin 3, claudin 4, claudin 7, E-cadherin, AR, and GGT1, we categorized TNBC into a basal-like subtype, a claudin low subtype, a molecular apocrine subtype, a mixed subtype showing characteristics of two different subtypes, and a null subtype not belonging to any of the subtypes identified.
  • Publication
    Open Access
    Distribution of exogenous metallothionein following intraperitoneal and intramuscular injection of metallothionein-deficient mice
    (F. Hernández y Juan F. Madrid. Universidad de Murcia. Departamento de Biología Celular e Histología, 2012) Lewis, Katherine E. Lewis; Chung, Roger S.; West, Adrian K.; Chuah, Meng Inn
    Metallothionein-I/II (MT-I/II) is a small metal-binding protein with antioxidant and neuroprotective properties, which has been used experimentally as a neurotherapeutic agent in multiple conditions. Therefore it is important to determine whether exogenous MT-I/II is retained in specific organs or expelled from the body following intramuscular and intraperitoneal injection. The distribution of exogenous MT-IIA (the major human MT-I/II isoform) was examined in MT-I/II-deficient mice, by immunohistochemistry of tissue samples and western blotting of urine samples. MT-IIA was detected within epithelial cells of the kidney cortical and medullary tubules within 1 hour of either intramuscular or intraperitoneal injection. Additionally, MT-IIA was detected within the urine at 1 hour after injection, indicating rapid absorbance into the circulation and filtration through the kidney glomerulus. A portion of the intramuscularly-injected MT-IIA remained within the muscle for at least 24 hours after injection. No MT-IIA was observed within the liver or the brain after either a single injection or a series of MT-IIA injections. These results are consistent with earlier reports that exogenously administered MT-IIA does not cross the intact blood-brain barrier, although a receptor for MT-I/II (megalin) is present in the choroid plexus. We postulate that due to losses through the urine, circulating MT-IIA levels drop rapidly after injection and do not permit transport across the choroid plexus. Peptide analogues of MT-I/II with similar neuroactive properties (emtins) may be more suited for CNS delivery.