Retroperitoneal non-secreting paraganglioma. Apropos of a case

Paragangliomas are rare tumors arising from extraadrenal chromaffin cells. These tumors are most commonly found in the adrenal gland but other locations are possible. A 79-year-old woman with abdominal pain underwent computed tomography (CT scan). Surgery was indicated because of the increase in the size of the tumor. Histopathological examination revealed a non secreting paraganglioma in the left retroperitoneum. Paragangliomas are rare neuroendocrine tumors. They have a greater potential for malignancy than pheochromocytomas due to metastases or local recurrence making surgical excision the treatment of choice.     

The neuroprotective effects of a locally acting IGF-1 isoform

In the last decade, dramatic progress has been made in elucidating the molecular defects underlying a number of neuromuscular diseases. With the characterization of mutations responsible for muscle and nerve dysfunction in several inherited pathologies, and the identification of novel signaling pathways, in which subtle alterations can lead to significant defects in tissue metabolism, the field is poised to devise successful strategies for treatment of this debilitating and often fatal group of human ailments. Yet progress in therapeutic application has been slow despite our newly gained knowledge of basic biology. Hence, where direct therapeutic approaches to address the primary diseases are still sub-optimal, it may be more effective to focus on strategies for improving neuromuscular function. Among potential candidates, insulin-like growth factor (IGF-1) has been involved in several anabolic pathways in both skeletal muscle and the nervous system and it is a promising candidate to attenuate neuromuscular diseases. In this review, we will discuss the role of IGF-1 isoforms in neuromuscular diseases and the contribution of muscle-produced IGF-1 (mIGF-1) to motor neuron survival and activity.     

Functional characterization of naturally occurring NR3C2 gene mutations in Italian patients suffering from pseudohypoaldosteronism type 1

OBJECTIVE: The renal form of pseudohypoaldosteronism type 1 (PHA1) is a rare disease caused by mutations in the human mineralocorticoid receptor gene (NR3C2). DESIGN: Aim of the study was to analyze the NR3C2 gene in three Italian patients with clinical signs of renal PHA1 and to evaluate the distribution of the -2G > C, c.538A > G, and c.722C > T single nucleotide polymorphism (SNP) pattern in the PHA1 patients and in 90 controls of the same ethnic origin. METHODS: Analysis of the NR3C2 gene sequence and of the polymorphic SNP markers. Functional characterization of the detected novel NR3C2 mutations utilizing aldosterone-binding assays and reporter gene transactivation assays. RESULTS: One novel nonsense (Y134X) and one novel frameshift (2125delA) mutation were detected. They exhibited no aldosterone binding and no transactivation abilities. No mutation was detected in the third patient. Haploinsufficiency of NR3C2 was ruled out by microsatellite analysis in this patient. The c.722T SNP was detected in 97% of alleles in the Italian population which is significantly different from the general German or US population. CONCLUSIONS: Molecular analysis of the NR3C2 gene in PHA1 patients is warranted to detect novel mutations in order to clarify the underlying genetic cause, which may extend the insight into relevant functional regions of the hMR protein. The effect the different distribution of the c.722T SNP is not clear to date. Further studies are necessary to provide evidence as to a possible advantage of a less sensitive hMR in southern countries.     

Detection of aromatase and estrogen receptors (ERalpha, ERbeta1, ERbeta2) in human Leydig cell tumor

A Leydig cell tumor is a rare neoplasm, deriving from the interstitial cells, whose pathogenesis has not been still defined. Leydig cells of normal adult testis are known as physiological targets for estrogens. However, some studies on transgenic rodents suggest a role of estrogens in the development of Leydig cell hyperplasia and Leydig cell tumor. Therefore, with the aim to evaluate a possible link between estrogens and testicular tumorigenesis, this study investigated the expression of aromatase and estrogen receptors (ERalpha, ERbeta(1), ERbeta(2)) in testes from two patients with Leydig cell tumor. A strong immunoreactivity for aromatase, ERbeta(1), and ERbeta(2), together with a detectable ERalpha immunostaining, was revealed in tumoral tissues. These findings were confirmed by western blot analysis of tumor extracts detecting a 55 kDa P450arom, a 67 kDa ERalpha band, a 59 kDa ERbeta(1) band, and a 53 kDa ERbeta(2) band. The pattern of ER expression in neoplastic cells appears different from that of control Leydig cells exhibiting only ERbeta(1) and ERbeta(2) isoforms. The authors hypothesize how the high estrogen production could play a role in the neoplastic transformation of Leydig cells, while the exclusive presence of ERalpha in tumoral cells could amplify estradiol-17beta signaling contributing to the tumor cell growth and progression.     

RhoA/Rho-kinase pathway: much more than just a modulation of vascular tone. Evidence from studies in humans

RhoA/Rho-kinase signaling and its relationship/balance with the nitric oxide level, angiotensin II and vasopressors for cardiovascular pathophysiology is of increasing importance, and its involvement goes far beyond blood pressure regulation. The deep involvement of this pathway in cardiovascular biology is now known to include a wide spectrum of conditions relating to the long-term complications of hypertension, and in general of cardiovascular pathophysiology, such as changes in cardiovascular structure (remodeling) and the induction of atherosclerosis, involvement in the pathophysiological relationships between inflammation and hypertension, and in those between hypertension, glucose metabolism and insulin resistance. Studies from our laboratory have made an important contribution to the understanding of the cellular and molecular mechanisms mediated by the RhoA/Rho-kinase pathway, which include all the aspects of cardiovascular pathophysiology in which this pathway plays a role. In addition, if it is considered that our contribution to the clarification of these mechanisms only comes from studies in humans, their impact on the scenario of the RhoA/Rho-kinase pathway's biology, essentially supported by studies 'in vitro' or in animal models, is immediate. This review examines all the aspects of RhoA/Rho-kinase signaling in the light of the available data, and gives an updated and useful overall picture of its involvement in cardiovascular pathophysiology.     

Do non-steroidal anti-inflammatory drugs influence the steroid hormone milieu in male athletes?

Prostaglandins modulate the hypothalamus-pituitary-adrenal and -gonadal axis pathways. We explored the effects of a single course of treatment with acetylsalicylic acid (ASA), an inhibitor of prostaglandin synthesis, on the steroid milieu in athletes. Morning plasma cortisol (F), dehydroepiandrosterone sulphate, free-testosterone, testosterone (T) and their ratios were evaluated before and after the administration of either ASA or placebo in twelve male athletes, when affected by minor musculoskeletal trauma and, as control, after a five/six week wash-out in healthy conditions respectively. One tablet of ASA (800 mg), or placebo, was administered two times daily for 10 days during treatment. All the volunteers suspended exercise training during treatment. The results revealed that compared to placebo, plasma F was significantly lower after ASA treatment (p = 0.023). Furthermore, the comparison of hormone's absolute and percentage of variations (Delta and Delta%) between ASA and placebo treatment showed significant differences respectively for DeltaF (p = 0.045), for DeltaT (p = 0.047), for DeltaT/F (p = 0.042), for DeltaF% (p = 0.04) and for DeltaT% (p = 0.049). Our data suggest that in comparison to placebo, a short-term ASA treatment is able to influence the plasma steroid milieu in athletes. Due to the observed variability of the individual hormonal patterns, further research is required to substantiate these findings.