Paolo Falaschi

The brain-gut-skin triangle: New peptides

New data on tachykinins and bombesins are displayed and the present situation of research on the novel amphibian skin peptides sauvagine and dermorphin is illustrated. The potent stimulant effect of sauvagine on ACTH and beta-endorphin release has been confirmed both in vivo and on columns of isolated and dispersed rat pituitary cells, and similarly the potent inhibitory effect on PRL and GH release, both in the rat and man. Particular emphasis is laid on the occurrence of sauvagine-like immunoreactivity in fish urophysis and in amphibian nervous structures, including the retina. It is suggested that the long-searched corticotropin releasing factor and PRL release-inhibiting factor may be a sauvagine-like peptide. Dermorphin, in its turn, has been found to cause, by intracerebroventricular injection, not only analgesia and catalepsy, but also conspicuous EEG and behavioral changes in the rabbit and chick, as well as a sharp reduction in gastric emptying time and gastric acid output in the rat, together with marked stimulation of PRL release.

INFLUENCE OF HYPERPROLACTINAEMIA DUE TO METOCLOPRAMIDE ON GONADAL FUNCTION IN MEN

Five clinically normal male volunteers were given metoclopramide, 10 mg t.d.s. for 6 weeks. During treatment prolactin concentrations were elevated (over 50 ng/ml) in all. LH, FSH, testosterone and cortisol concentrations were not altered. No change was observed in LH or FSH responses to LHRH testing 4 weeks after the beginning of therapy, compared with pre‐treatment values. A reduction in seminal volume and total sperm count were observed in each subject. Four noticed a decrease in libido and three lost spontaneous erections. While the metoclopramide‐induced hyperprolactinaemia could be the cause of the observed changes in semen and erectile activity, it is possible that this dopamine receptor blocking drug might directly affect central or peripheral mechanism of erection, the testes or accessory organs.

Recent advances in the role of cortisol and metabolic syndrome in age-related degenerative diseases

AbstractThe metabolic syndrome (MetS) presents an increasing prevalence in elderly people. A significant role in MetS is played by the stress response and cortisol. The hypothalamic–pituitary–adrenal (HPA) axis activity is increased by central (loss of hippocampal glucocorticoid receptors) and peripheral (11β-hydroxysteroid dehydrogenase type 1, 11β-HSD1, hyperactivity) mechanisms. The HPA hyperactivity has been found in chronic diseases affecting the endocrine (abdominal obesity with MetS, type 2 diabetes), cardiovascular (atherosclerosis, essential hypertension), and nervous systems (dementia, depression), in aging. A novel therapeutic approach (11β-HSD1 inhibition) is promising in treating the HPA axis hyperactivity in chronic diseases with MetS. A large-scale national clinical trial (AGICO, AGIng, and COrtisol study) has been proposed by our group to evaluate the role of cortisol and MetS in the main pathologies of aging (vascular and degenerative dementia, cardiovascular diseases, type 2 diabetes, abdominal obesity).

Sex-related variations in serum nerve growth factor concentration in humans

A role of nerve growth factor (NGF) in the neuro-endocrine-immune interactions has been recently suggested by the presence of NGF and its receptors in cells of the immune and endocrine systems. The improvement in the comprehension of the role played by NGF in humans is linked to the availability of a sensitive and reliable method to quantify NGF concentrations in body fluids and tissues. As a consequence of different methods used, normal levels of human serum NGF reported in the literature show wide differences. The present results indicate that ELISA appears very sensitive (detection limit 1.4pg/ml) and allows the discrimination of subtle variations of serum NGF concentrations. ELISA performed in serum obtained from men indicated that NGF concentration was 40.8+/-10.8pg/ml, whereas women showed significantly lower levels that were influenced by the menstrual cycle. In particular, the mean value of this neurotrophin during the follicular phase was 8.2+/-1.4pg/ml; the luteal phase, in turn, showed levels up to 14.4+/-2.9pg/ml. The difference of serum NGF concentrations between the follicular and luteal phase in each woman was statistically significant. Differences in NGF concentrations between men and women (in both phases of the menstrual cycles) were also statistically significant. In conclusion, a possible role of sex steroids as modulators of NGF secretion in humans is strongly supported by the present paper. However, mechanisms underlying this phenomenon are still unknown. The evidence indicating physiological sex hormone-related variations in NGF levels would be of interest in view of the possible use of circulating NGF modifications as a laboratory biomarker in different diseases.

The management of hip fracture in the older population. Joint position statement by Gruppo Italiano Ortogeriatria (GIOG).

This document is a Joint Position Statement by Gruppo Italiano di OrtoGeriatria (GIOG) supported by Società Italiana di Gerontologia e Geriatria (SIGG), and Associazione Italiana Psicogeriatria (AIP) on management of hip fracture older patients. Orthogeriatric care is at present the best model of care to improve results in older patients after hip fracture. The implementation of orthogeriatric model of care, based on the collaboration between orthopaedic surgeons and geriatricians, must take into account the local availability of resources and facilities and should be integrated into the local context. At the same time the programme must be based on the best available evidences and planned following accepted quality standards that ensure the efficacy of the intervention. The position paper focused on eight quality standards for the management of hip fracture older patients in orthogeriatric model of care. The GIOG promotes the development of a clinic database with the aim of obtaining a qualitative improvement in the management of hip fracture.

Targets of Anti-glucocorticoid Therapy for Stress-related Diseases

The stress response during chronic conditions increases vulnerability to diseases through the activation of adaptive systems, in particular, the hypothalamus-pituitary-adrenal (HPA) axis. Dysregulation in HPA activity (central and peripheral) has been reported in chronic diseases, like metabolic syndrome, type-2 diabetes mellitus, atherosclerosis-related disease, essential hypertension, dementia, depression, particularly during comorbid conditions. Different targets of anti-glucocorticoid treatment have been proposed, acting at supra-hypothalamic, HPA axis, glucocorticoid receptor and post-receptor levels. The recent promising patents on the therapy against glucocorticoid-mediated damage will be presented and discussed.

Amino acid sequence homologies between HCV polyprotein and thyroid antigens

Recent evidence in the literature suggests that molecular mimicry between viral and self antigens may be involved in the pathogenesis of autoimmune thyroid diseases in patients with chronic hepatitis C virus (HCV) infections [1–3]. Chronic HCV infection has been reported to be associated with thyroid autoimmunity and thyroid function disorders with a mean incidence of 10% and 3%, respectively [4, 5]. Alfa-IFN therapy may exacerbate or induce underlying latent thyroid disorders, increasing the incidence of thyroid autoimmunity and thyroid function disorders to 20% and 11%, respectively [4, 5]. In keeping with the tenets of the clonal selection theory of acquired immunity, an infectious agent may circumvent the deletion of anti-self lymphocytes activating clones with receptors sufficiently degenerated to respond to mimicking epitopes and host antigens [6]. A minimum of five to six amino acids are necessary to induce an immune response, and the probability of 20 amino acids occurring in six identical residues between two proteins is 206 (for each peptide, irrespective of the sequence) or 1 in 128 000 000 [7]. We performed the comparison between the amino acid sequence of the HCV polyprotein and five tissue-specific antigens of human thyroid, available in the database on www.ncbi.nlm.nih.gov/pubmed. In particular, we examined the following HCV genotypes (with the respective NCBI sequence identification number): HCV1a (GI:130455), HCV1b (GI:130469), HCV1c (GI:385131), HCV2a (GI:130466), HCV2b (GI:130468), HCV2c (GI:555104), HCV3a (GI:514395), HCV3b (GI:676877), HCV4a (GI:402474), HCV5a (GI:2462303) and HCV6a (GI:2326455). Regarding the thyroid gland, we examined the following tissue-specific antigens: the thyroglobulin (Tg) (GI:12644093), the thyroid peroxidase (TPO) (GI:129830), the thyrotropin receptor (TSHr) (GI:136448), the sodium/iodide symporter (NaIS) (GI:12643359) and Pendrin (GI:6174895). Sequence alignments were carried out using the BLASTp, short nearly exact matches and BLASTp2 protein-protein comparison program (available at www.ncbi.nlm.nih.gov/BLAST). Amino acid sequence homologies between the HCV polyprotein and the thyroid antigens are given in detail in Fig. 1, showing the presence of identical/conservative residues in the peptides. The following proteins of the HCV polyprotein have been examined: C (capsule, core protein), E1 (envelope glycoprotein 1), E2 (envelope glycoprotein 2, NS1), p7, NS2 (non-structural protein 2), NS3 (non-structural protein 3, protease/helicase), NS4a (non-structural protein 4a), NS4b (nonstructural protein 4b), NS5a (non-structural protein 5a) and NS5b (non-structural protein 5b, RNA polymerase). The homologies between the thyroid and the viral peptides ranged from 62.5 % (five identical residues out of eight amino acids in the sequence) to 87.5% (seven identical residues out of eight amino acids in the sequence). The frequency of the homology increased up to 100%, when the conservative substitutions were included in the analysis (ten out of ten identical/conservative amino acids in the sequence, as indicated in Fig. ​Fig.11 for NaIS444 and HCV1a-NS4a1665). Fig. 1 Amino acid sequence homologies between the thyroid antigens and the HCV polyprotein (see text for abbreviations). *, Identical residues; +, conservative substitution. In each sequence, the first left-side residue inside the box corresponds to the number ... We found the presence of short peptides (eight to eleven amino acids) with a high degree of homology (62.5–100%) between the HCV polyprotein and five thyroid antigens (Tg, TPO, TSHr, NaIS and Pendrin). The homology was not restricted to a single HCV genotype or to a single thyroid antigen. The highest degree of homology was between the NaIs and the HCV1a-NS4a protein. The Tg antigen had the highest number of homologies with the different HCV genotypes. Previous studies examining 20 amino acid-length peptides showed 41.7–58.3% sequence homologies between TPO and HCV-NS5a and HCV-NS2, increased to 75.0% when including conservative/identical residues [3]. We found mimicry between the TSH-r and the N-terminal hypervariable region 1 (HVR1) of E2 in HCV1a, which is well known to be involved in chronic HCV infection [8]. The length of the short peptides is consistent with the presentation of the self/viral antigens with the I class HLA molecules to CD8 positive lymphocytes, as the II class HLA molecules usually bind longer peptides, and the mimic peptides may be involved in the acceleration of autoimmune disorders occurring in chronic HCV infection [9]. In our examination, the RLGVRATRK-HCV2b-C43 sequence presented homology with the RLGVNVTWK-Tg1361 sequence; the same viral peptide has been recently identified as a HLA-A3 supertype-restricted cytotoxic T-lymphocyte epitope in patients with HCV infections [10]. The more frequent and earlier appearance of anti-Tg antibodies in the clinical course of the thyroid autoimmunity in HCV IFN-treated patients may be related to the high number of homologies between the Tg antigen and the HCV polyprotein, whereas the anti-TPO antibodies reflect a more advanced and aggressive autoimmune thyroid destruction [11]. Further studies are necessary in order to evaluate the clinical relevance of the presence of the molecular mimicry between the HCV and the thyroid antigens in the progression of autoimmune disease.

Diagnosis of hepatic glycogenosis in poorly controlled type 1 diabetes mellitus

Hepatic glycogenosis (HG) in type 1 diabetes is a underrecognized complication. Mauriac firstly described the syndrome characterized by hepatomegaly with altered liver enzymes, growth impairment, delay puberty and Cushingoid features, during childhood. HG in adulthood is characterized by the liver disorder (with circulating aminotransferase increase) in the presence of poor glycemic control (elevation of glycated hemoglobin, HbA1c levels). The advances in the comprehension of the metabolic pathways driving to the hepatic glycogen deposition point out the role of glucose transporters and insulin mediated activations of glucokinase and glycogen synthase, with inhibition of glucose-6-phosphatase. The differential diagnosis of HG consists in the exclusion of causes of liver damage (infectious, metabolic, obstructive and autoimmune disease). The imaging study (ultrasonography and/or radiological examinations) gives information about the liver alterations (hepatomegaly), but the diagnosis needs to be confirmed by the liver biopsy. The main treatment of HG is the amelioration of glycemic control that is usually accompanied by the reversal of the liver disorder. In selected cases, more aggressive treatment options (transplantation) have been successfully reported.

Association of Severity of Osteoarthritis and Carotid Atherosclerosis in Patients with Metabolic Syndrome

Study Background: Increasing evidence in the literature suggests a link between osteoarthritis and atherosclerosis represented by the pro-inflammatory state, independently by concurrent factors such as the joint overload caused by obesity. In this study we examined the role of metabolic syndrome, a cluster of cardiovascular risk factors with a significant pro-inflammatory background, on the severity of both carotid atherosclerosis and osteoarthritis. Methods: We evaluated 68 patients (14 males, 54 females) with (mean±standard error) age and body mass index of 76.99±1.01 years and 27.63±0.62, respectively. The subjects were divided in two groups by the presence of metabolic syndrome (according to Adult Treatment Panel III criteria). Each patient received a score of severity for carotid atherosclerosis (by echo-doppler examination of supra-aortic arteries) and for osteoarthritis (by standard X-ray). The s ites of osteoarthritis was divided in related or not related to weight overload. Results: The body mass index of patients with (n.42) or without metabolic syndrome (n.26) were 28.94±0.84 and 25.87±0.77, respectively (p<0.025). The severity of carotid atherosclerosis were 1.59±0.17 and 0.82±0.18 in the patients with or without metabolic syndrome (p<0.01). The severity of osteoarthritis were 2.59±0.15 and 2.04±0.27 in the patients with or without metabolic syndrome (p=0.06). Metabolic syndrome was significantly related to severity score of carotid atherosclerosis and osteoarthritis (r=0.932 p<0.01 and r=0.936 p<0.01, respectively). Severity score of carotid atherosclerosis and osteoarthritis were significantly related (r=0.895 p<0.05). Conclusion: In this preliminary study, we showed a link between severity of osteoarthritis and atherosclerosis in metabolic syndrome, pointing out the possibility of a common background belonging to the degenerative and inflammatory reactions involving both the cardiovascular and articular system.

Association of diffuse liver glycogenosis and mild focal macrovesicular steatosis in a patient with poorly controlled type 1 diabetes

We report a case of a 17-year-old female with type 1 diabetes, presenting hepatomegaly and elevated aminotransferases. She received frequent hospitalization for hyperglycaemia and poor glycaemic control (HbA1c = 13%, weight = 52 kg, height = 156 cm, BMI = 21.4). In particular, her compliance to the prescribed diet was poor, with frequent meals and subsequently self-prescribed extra-dose of insulin, in order to control her blood glucose concentrations. During the clinical course she presented hepatomegaly and raised aminotransferase levels (up to AST = 1,620 U/l and ALT = 629 U/l). An extensive evaluation for infectious, autoimmune, toxic, obstructive and metabolic liver disorders (including HAV, HBV, HCV, cytomegalovirus, EBV, ANA, SMA, LKM, AMA, ENA, Wilson’s disease, a1-antitrypsin deficiency, haemochromatosis, ornithine transcarbamylase deficiency, celiac disease) resulted completely negative. An ultrasound (US) scan confirmed an enlargement of the liver with an increased echo level, the absence of the echo attenuation in the deep liver regions and the normal diameters of hepatic and portal veins. A liver biopsy was carried out after 6 months of repeated persisting high aminotransferase levels. Normal lobular structure, absence of portal and lobular inflammation, presence of a mild macrovesicular steatosis with a focal distribution and a large aumont of cytoplasmic glycogen storage with nuclear inclusions in the hepatocytes (Fig. 1), were observed. In order to obtain an improvement of the glycaemic control and a reduction of both hepatomegaly and aminotransferases levels adherence to a hypoglycidic diet, proper psychological support and progressive reduction of insulin requirement were started. In fact, reductions of both HbA1c and GOT/GPT levels (10.7% and 54/61 U/l, respectively), were progressively obtained after over a year of follow-up, even though without reaching a normalization yet, due to a persisting poor diet compliance. Hepatomegaly was reduced but still present.