RAGE inhibition blunts insulin-induced oncogenic signals in breast cancer

The receptor for advanced glycation end products (RAGE) is implicated in diabetes and obesity complications, as well as in breast cancer (BC). Herein, we evaluated whether RAGE contributes to the oncogenic actions of Insulin, which plays a key role in BC progression particularly in obese and diabetic patients. Analysis of the publicly available METABRIC study, which collects gene expression and clinical data from a large cohort (n = 1904) of BC patients, revealed that RAGE and the Insulin Receptor (IR) are co-expressed and associated with negative prognostic parameters. In MCF-7, ZR75 and 4T1 BC cells, as well as in patient-derived Cancer-Associated Fibroblasts, the pharmacological inhibition of RAGE as well as its genetic depletion interfered with Insulin-induced activation of the oncogenic pathway IR/IRS1/AKT/CD1. Mechanistically, IR and RAGE directly interacted upon Insulin stimulation, as shown by in situ proximity ligation assays and coimmunoprecipitation studies. Of note, RAGE inhibition halted the activation of both IR and insulin like growth factor 1 receptor (IGF-1R), as demonstrated in MCF-7 cells KO for the IR and the IGF-1R gene via CRISPR-cas9 technology. An unbiased label-free proteomic analysis uncovered proteins and predicted pathways affected by RAGE inhibition in Insulin-stimulated BC cells. Biologically, RAGE inhibition reduced cell proliferation, migration, and patient-derived mammosphere formation triggered by Insulin. In vivo, the pharmacological inhibition of RAGE halted Insulin-induced tumor growth, without affecting blood glucose homeostasis. Together, our findings suggest that targeting RAGE may represent an appealing opportunity to blunt Insulin-induced oncogenic signaling in BC.

The effect of noise on serum and urinary magnesium and catecholamines in humans

We have studied whether a short-term exposure to loud noise was able to modify urinary catecholamine excretion and serum concentration and urinary excretion of magnesium and other related electrolytes. In 25 healthy volunteers, blood and urine concentrations of magnesium, calcium, phosphorus and creatinine, and urinary catecholamines were measured before and after exposure to noise in an industrial plant. Samples were collected at 08:00 h on the day of the experiment and soon after noise exposure (at 20:00 h). Two further urine samples were collected the following day and 2 days after the experiment, always at 08:00 h in the morning. The sound energy average level was 98 dB(A), but peak levels reached 108 dB(A). Urinary catecholamines were determined by high-performance liquid chromatography. Serum magnesium and calcium were significantly increased after exposure to noise, whereas phosphorus displayed a similar but non-significant trend (P = 0.065). Multivariate analysis of variance (ANOVA) showed significant differences both among subjects (P < 0.001) and after exposure (P < 0.001). Adrenaline, noradrenaline and dopamine values were not significantly different after exposure to noise (P > 0.05). Urinary magnesium levels were significantly different across time (P = 0.017). Urinary calcium levels were not significantly different across time (P = 0.36). Urinary phosphate values were increased after exposure to noise (P = 0.007); urinary creatinine was not changed after exposure (P > 0.05). Our study shows that noise induces significant increases of serum calcium and magnesium, with a borderline increase of serum phosphorus; this in turn is reflected in a significantly increased urinary excretion of magnesium and phosphate after exposure, which lasts for the following 2 days. Urinary calcium and creatinine were not modified by noise. The difference in catecholamine values did not reach statistical significance. Thus, we failed to substantiate a significant correlation between catecholamine secretion and magnesium metabolism, as others had suggested.

The time course of high-frequency bands (15-45 Hz) in all-night spectral analysis of sleep EEG

OBJECTIVE

The EEG spectral content of all-night sleep recordings obtained in 7 healthy young subjects, aged 18-20 years, including frequencies up to 45 Hz, was studied in order to detect eventual changes in the high-frequency range similar to those reported by magnetic field recording during REM sleep at 40 Hz.

METHODS

For this purpose, power spectra were calculated with a fast Fourier transform and the power of the bands ranging 0.75-4.50 Hz (Delta), 4.75-7.75 (Theta), 8.00-12.25 (Alpha), 12.50-15.00 (Sigma), 15.25-24.75 (Beta), 25.00-34.75 (Gamma1), and 35.00-44.75 (Gamma 2) was calculated for-the whole period of analysis (7 h). Also two additional time series: the ratio between Beta and Gamma2, and between Gamma1 and Gamma2 were calculated (Beta and Gamma ratios).

RESULTS

Beta and Gamma1 showed small changes with a tendency to increase during REM sleep; Gamma2, on the contrary, showed small changes with a tendency to decrease during REM sleep. Beta and Gamma ratio peaks were clearly correlated with the occurrence of REM sleep. The small changes shown by Beta, Gamma1 and Gamma2 were not statistically significant; on the contrary, Beta ratio and Gamma ratio showed the most important statistical significance values being highest during REM sleep and lowest during slow-wave sleep. Finally, the calculation of the linear correlation coefficient and of the cross-correlation between the different bands showed a clear reciprocity between Delta and Beta and Gamma ratios.

CONCLUSIONS

Our study shows a new method for the analysis of high frequencies (up to 45 Hz) in the scalp-recorded sleep EEG which allowed us to better define, as compared to previous studies on the same topic, the changes in power characteristically associated with REM sleep and correlated with the REM/non-REM ultradian rhythm, and to propose it as a tool for future studies.

Cyclic alternating pattern and spectral analysis of heart rate variability during normal sleep

The natural arousal rhythm of non-rapid eye movement (NREM) sleep is known as the cyclic alternating pattern (CAP), which consists of arousal-related phasic events (Phase A) that periodically interrupt the tonic theta/delta activities of NREM sleep (Phase B). The complementary condition, i.e. non-CAP (NCAP), consists of a rhythmic electroencephalogram background with few, randomly distributed arousal-related phasic events. Recently, some relation between CAP and autonomic function has been preliminarily reported during sleep in young adults by means of spectral analysis of heart rate variability (HRV). The present study was aimed at analysing the effects of CAP on HRV in a group of normal children and adolescents. Six normal children and adolescents (age range 10.0-17.5 y) were included in this study. All-night polygraphic recordings were performed after adaptation to the sleep laboratory. Six 5-min epochs were selected from sleep Stage 2 and six from Stages 3 and 4 (slow-wave sleep), both in CAP and NCAP conditions. From such epochs, a series of parameters describing HRV was then calculated, in both time and frequency domains, on the electrocardiographic R-R intervals. Statistical comparison between CAP and NCAP epochs revealed a significant difference for most of the frequency domain parameters (increase of the low-frequency band, increase of the low-frequency/high-frequency ratio and decrease in the high-frequency band during CAP) both in Stage 2 and in slow-wave sleep. Our results demonstrate that the physiological fluctuations of arousal during sleep described as CAP are accompanied by subtle, but significant, changes in balance between the sympathetic and vagal components of the autonomic system.

Correlation dimension of EEG slow-wave activity during sleep in narcoleptic patients under bed rest conditions

The calculation of the correlation dimension (D2) was applied to the study of the profiles of EEG slow-wave activity in nine narcoleptic subjects and nine sex- and age-matched control subjects who, following a baseline night recording, were maintained on 16 h of diurnal sleep deprivation and, thereafter, submitted to a 32-h bed rest protocol. The reversibility test allowed us to reject the null hypothesis that the time series considered in our study were generated by a static transformation of a linear Gaussian random process. Similarly, all profiles showed a positive largest Lyapunov exponent. Finally, the computation of D2 showed an average value of 5.27 (0.68 S.D.) in normal controls and 4.05 (1.49 S.D.) in narcoleptic patients (p = 0.067). Four of the narcoleptic patients showed values of D2 lower than 4, this was never observed in the normal controls (p = 0.0294). This study indicates that the mechanism of sleep-wake regulation in narcolepsy shows a somewhat lower degree of complexity as compared to normal controls. In particular, these data seem to confirm the already suggested different and simpler coupling between the homeostatic process of sleep regulation and the circadian and ultradian drives to sleep that occurs in bed rest condition in this disease.

AKEntAnnos. The Sardinia Study of Extreme Longevity

This paper describes an epidemiological study performed in all centenarians living in Sardinia, a large island located in the Mediterranean sea, 120 Km from the Italian coast. Due to its long-standing isolation, low immigration rate, high endogamy and rather uniform lifestyle, Sardinia offers an ideal setting in which to study the genetic traits associated with extreme longevity and successful aging. A total of 233 potentially eligible centenarians were traced in the entire territory. Of these, 66 died prior to being interviewed, 11 were not found and unknown, and 15 refused to be interviewed. A multidimensional home interview was administered to 141 centenarians, and an equivalent number of 60-year-old controls matched for gender and area of residence. Furthermore, 41 living siblings of the centenarians, and 41 age- and sex-matched controls for these siblings were also studied. The prevalence of centenarians was 13.56 per 100,000, and the female/male ratio was approximately 2. Prevalence and female/male ratio were consistent across the four Sardinian municipalities and are, respectively, higher and lower than those reported in other population-based surveys. A number of methodological problems confronted in doing the field work, and plans for future analysis of this rich dataset are discussed.

Heart rate variability and apnea during sleep in Down's syndrome

Autonomic system dysfunction has been reported to occur frequently in patients with Down's syndrome (DS) and is constituted mainly by an imbalance between the sympathetic and vagal systems. The analysis of heart rate variability (HRV) during sleep is a quantitative reliable method for studying such a mechanism, but it has not yet been extensively and adequately applied in DS. In this study, HRV during sleep was evaluated in seven DS patients and in six normal controls, by also controlling for the presence of sleep apnea or arousal. The main results were an increased sympathetic function (low-frequency component of HRV) and a decreased vagal activity (high-frequency component of HRV) in DS with respect to normal controls, during apnea-free periods. Moreover, the presence of apnea, in DS, induced a further significant increase in low-frequency and very low-frequency components of HRV during sleep Stage 2. This study provides additional evidence of a brainstem dysfunctioning in DS, responsible for the abnormal imbalance between the sympathetic and vagal systems and confirms the brainstem involvement already suggested in the literature in order to explain brainstem-auditory evoked potential abnormalities and central sleep apnea in these patients.

Correlation dimension of EEG slow-wave activity during sleep in children and young adults

In a recent work, the calculation of the correlation dimension (CD) of the profiles of EEG slow-wave activity during sleep in 7 young subjects, allowed us to conclude that sleep-regulation might be considered a deterministic non-linear process with an average dimension above 3. In this paper we report the results of the calculation of the CD of EEG slow-wave activity in 20 normal subjects (children and young adults) who slept in the laboratory for 3 consecutive nights. The results confirm that it is possible to calculate the CD in most normal profiles (33 out of 40) and to discriminate between chaos and noise. The lower limit of CD was found as ranging between approximately 2.5 and 4.5, it did not show significant changes across consecutive nights in the same subject and did not seem to change significantly with age in children and young adults.

Lack of influence of apolipoprotein E4 on lipoprotein levels in the island population of Sardinia

BACKGROUND

In this study, the apolipoprotein E (apoE) genotypes as well as plasma lipid and lipoprotein levels have been determined for the first time in 633 healthy and unrelated inhabitants on the island of Sardinia (291 men and 342 women, age range 6-89 years), randomly selected in the four districts of Sardinia among healthy people having parents and grandparents born in the same geographic area. This island lies in the centre of the western Mediterranean sea with a well-recognized peculiar and preserved genetic background. The epsilon 3 allele frequency (0.897) is higher than that previously reported in southern and mainland Italy and is one of the highest in Europe and among Caucasians; epsilon 2 allele frequency (0.040) is the lowest in Europe; epsilon 4 (0.063) is unusually low and, most interestingly, does not change in the different age groups, i.e. does not decrease in old subjects.

RESULTS

Lipid and lipoprotein analysis confirm that total cholesterol and low-density lipoprotein (LDL)-cholesterol levels are lower than those described in mainland Italy; moreover, in this large Sardinian series, accurately selected, epsilon 4 allele did not influence total cholesterol (P = 0.270), LDL-cholesterol (P = 0.667) and high-density lipoprotein (HDL)-cholesterol (P = 0.549) as in other populations. In contrast, subjects carrying the epsilon 2 allele were found to have significantly lower total cholesterol (P = 0.001) and LDL-cholesterol (P = 0.001) levels than epsilon 3 carriers.

CONCLUSION

The low epsilon 4 frequency and the lack of influence of this allele on lipid metabolism is a unique characteristic and, to date, has been described only in Sardinia among Caucasians; it might contribute to the low prevalence of coronary artery disease in this island.

[The usefulness of thyroxine treatment after subtotal thyroidectomy for endemic goiter]

The aim of the present study was to assess the appropriateness and value of prophylactic thyroxine therapy in the treatment of postoperative complications (relapse, postoperative hypothyroidism) following subtotal thyroidectomy for endemic goiter. The study was carried out in a group of 139 patients undergoing subtotal thyroidectomy for endemic goiter between 1978 and 1987. Clinical follow-up included hematochemical and scintigraphic analyses. Patients were divided into two groups. The first group included 74 patients who received postoperative hormone replacement therapy. The second group of 65 patients did not receive any treatment. results show that hormone replacement therapy is unnecessary in most cases since the majority of patients require euthyroid values a few months after operation. Thyroxine therapy was indicated, however, in cases of clinically evident postoperative hypothyroidism which persisted during follow-up.

Plasma lipids in beta-thalassemia minor

Because total cholesterol levels have been found to be lower in patients affected by thalassemia major and intermedia, we examined the plasma lipid pattern of 628 beta-thalassemia trait carriers and 4552 controls in order to evaluate whether the plasma lipid impairment is also present in the heterozygous state. Total cholesterol and low density lipoprotein (LDL)-cholesterol levels were significantly lower in beta-thalassemia trait carriers when compared to controls, whereas plasma triglycerides and high density lipoprotein (HDL)-cholesterol levels did not differ between the two groups. We suggest that accelerated erythropoiesis and increased uptake of LDL by macrophages and histiocytes of the reticuloendothelial system are the main determinants of low plasma cholesterol levels in heterozygous thalassemia.

[Incidence of Australia antigen (HBs Ag) in a group of apparently healthy population of the Sassari province]

In 3828 subjects (1489 males and 2339 females) apparently healthy was investigated the presence in the serum of Australia antigen and of corrispondent antibody with electrosyneresis, the activity of the G6PD eritrocytic and the eventual condition of carrier of microcytemic tare. An incidence of HBs Ag of 1.83% (2.75% in males and 1.24% in females) without any statistically important differences in the age groups and habitual residence and also the grade of G6PD eritrocytary activity was detected. A more elevated statistical incidence was observed among the carriers of thalassemic caracter never transfused. The anti HBs Ag antibodes were observed in 0.26% of the examined subjects.