The Effect of Metformin Treatment on Disease Control in Patients with Acromegaly

BACKGROUND

The increase in portal insulin levels has been shown to upregulate growth hormone receptor expression in the liver, leading to increased insulin-like growth hormone- 1 levels. Metformin inhibits hepatic gluconeogenesis and reduces fasting insulin.

OBJECTIVE

We evaluated the effect of metformin treatment in patients with acromegaly on growth hormone, insulin-like growth hormone-1, and pituitary adenoma size.

METHODS

Patients who were followed up with the diagnosis of acromegaly in Istanbul University- Cerrahpaşa, Cerrahpaşa Medical Faculty were evaluated. The patients were divided into three groups after pituitary adenectomy as those who received somatostatin receptor ligand and metformin treatment (group A), somatostatin receptor ligand treatment only (group B), and those who received metformin treatment only (group C). Groups A and B were compared with each other, and patients in group C were compared among themselves.

RESULTS

While the median insulin-like growth factor-1 level decreased to 170 ng/ml in Group A after the treatment, the median insulin-like growth factor-1 level decreased to 229 ng/ml in Group B, and a statistically significant difference was found between the two groups (p =0.020). There was no significant difference in post-treatment growth hormone levels and residual adenoma sizes between groups A and B (p >0.005). In group C, there was no significant difference in growth hormone values pre-and post-metformin treatment (p =0.078); however, the median insulin-like growth factor-1 level decreased from 205 ng/ml to 168 ng/ml during metformin treatment and was found to be statistically significant (p =0.027).

CONCLUSION

Due to the effect of metformin treatment on insulin-like growth factor-1 values in patients with acromegaly, it can be used in disease control, as well as diabetes treatment.

Risk of impulse control disorders in patients with Cushing's disease: do not blame cabergoline but do not give up caution

PURPOSE

To asses risk of new-onset impulse control disorders (ICDs) in patients with Cushing's disease (CD) who initiated cabergoline (CBG) and to determine frequency of ICDs in CBG-treated patients with CD.

METHODS

This naturalistic observational study had prospective and cross-sectional arms which included patients at five referral centers based in Istanbul. Patients who were scheduled for CBG were assigned to prospective arm. These patients underwent neuropsychological tests (Barratt Impulsiveness Scale, Minnesota Impulsive Disorders Interview, Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease-Rating Scale, Go/No-Go Task, Iowa Gambling Task, and Short Penn Continuous Performance Test) for assessment of impulsivity and psychiatric evaluations at baseline, 3, 6, and 12 months of CBG treatment. Impulsivity and new-onset ICDs were prospectively assessed. Patients with CD with current CBG treatment for ≥ 3 months and matched CBG-naïve patients with CD were included in cross-sectional arm. These patients underwent the same neuropsychological and psychiatric assessments. The impulsivity and frequency of ICDs were compared between CBG-treated and CBG-naïve patients with CD.

RESULTS

The follow-up duration of prospective cohort (n = 14) was 7.3 ± 2.3 months. One patient developed major depressive episode and another patient developed compulsive gambling after CBG. We observed no significant changes in impulsivity scores during follow-up. In cross-sectional arm, CBG-treated (n = 34) and CBG-naïve patients (n = 34) were similar in impulsivity scores and frequency of ICDs [3 patients (8.8%) vs. 2 patients (5.9%) respectively, p = 1.0].

CONCLUSION

CBG-treated patients with CD appeared to have a low risk of ICDs, suggesting that CBG still holds promise as a safe agent in CD.

MO055THE IMPACT OF THE COVID-19 PANDEMIC ON MOOD STATUS AND TREATMENT ADHERENCE IN PATIENTS WITH FABRY DISEASE

Background and Aims

Fabry disease is a rare metabolic disorder, lifelong enzyme replacement therapy with recombinant human alpha-galactosidase A (agalsidase) constituted the cornerstone of disease-specific therapy. COVID-19 pandemic and epidemic control measures including lockdowns impaired access to health care services. We examined the effect of COVID-19 pandemic and lockdown measures on mood status and management of Fabry disease patients.

Method

We conducted a cross-sectional study between October 2020 and December 2020. We used the Hospital Anxiety and Depression Scale (HADS) to evaluate the mood statuses of FD patients and the Morisky Medication Adherence Scale (MMAS-4) to assess patient adherence. We also examined age and sex-matched control group to compare mood status.

Results

A total of 68 (Male 48.5 %, mean age 37.0) FD patients were under regular follow-up in our institution, 59 of those patients were taking ERT every other week. Two of our patients had reported having a COVID-19 infection, and both of them recovered. 25 patients reported to miss an ERT for a median of one dose, 16 of these 25 patients have reported that they did not come to the hospital because of infection fear. Half of the patients had adopted home-based infusion; they arranged a nurse for home-based infusion therapy by their own means. According to MMAS-4 FD patients had good adherence to their therapy (Median score 0, range 0-2).  Mood status of FD patients and controls are shown in Table 1. Both HADS depression and anxiety scores were higher in the control group compared to FD patients. Additionally, abnormal scores were more prevalent for HADS depression scores in controls (Figure 1).

Conclusion

We found that the mood status of FD patients was better than the control group. Traumatic growth may be an important factor to explain this finding. Their adherence to therapy was good. Home-based therapy was the preferred method by the patients. Government-supported home therapy programs might be beneficial for FD patients to increase adherence to the therapy.

Investigation the relaxant effects of proton pump ınhibitors and their relaxation mechanism on sheep sphincter of Oddi

Background

Using a relaxant agent before an endoscopic retrograde cholangiopancreatography (ERCP) might reduce complications.

Study Aims

We aimed to investigate the relaxant effects of proton pump inhibitors (PPIs) on sheep sphincter of Oddi (SO) and the mechanisms that might take part in this relaxant effect.

Patients and Methods

The sheep SO was mounted in an organ bath filled with Krebs-Ringer bicarbonate solution under 1.5 g tension and the relaxant effects of PPIs were evaluated in the tissues precontracted by carbachol (10^-6 mol/l). The relaxant responses to the PPIs were tested in the presence of various blockers to enlighten the underlying mechanism by the PPIs.

Results

The PPIs exerted relaxant responses in a concentration-dependent manner in the sheep SO (P < 0.05). Esomeprazole produced the strongest relaxation. The administration of atropine, indomethacin, L-NAME, methylene blue, clotrimazole, glibenclamide, and 4-aminopyridine into the organ baths did not change the relaxations induced by PPIs in vitro (P> 0.05). On the other hand, Ca⁺²-activated potassium channel blocker tetraethylammonium (TEA) reduced the relaxation responses created by PPIs (P < 0.05).

Conclusions

The present study suggests that PPIs create relaxation on SO partially via Ca⁺²-activated potassium channels. PPIs, especially esomeprazole, may be beneficial during the ERCP procedure. Further clinical studies are needed to confirm our results.

Elastostatic reversibility in thermally formed bulk metallic glasses: nanobeam diffraction fluctuation electron microscopy

The unparalleled shaping ability of bulk metallic glasses can revolutionize commercial products having multi-length scale features with a processing time of several minutes. Despite the widespread shaping ability of these polymer-like multicomponent alloys, thermoplastic forming (TPF) can severely degrade the intrinsic properties, particularly when complex stress states are activated. The present work emphasizes the importance of elastostatic loading (ESL) which not only fully reverses deteriorated room temperature plasticity originating under TPF or post-cryostatic conditions, but also activates a rejuvenation mechanism by rendering an extended resistance against strain softening. Furthermore, the reduction in the supercooled liquid region and crystallization enthalpy measured by differential scanning calorimetry are found to be temporary, and can be fully reversed to the initial condition. HRTEM imaging of the samples are performed with an imaging spherical aberration corrector. Individual nanobeam diffraction patterns obtained by the fluctuation electron microscopy (FEM) measurements are acquired using a scanning transmission electron microscope with a probe size of 1.2 nm from a 10 × 10 raster, yielding 100 diffraction patterns. The normalized variance of a series of nanodiffraction patterns of the post-elastostatically loaded sample reveals a height decrease in the first broad peak of normalized intensity variance V(k) suggesting modifications in the medium-range structural order which in turn dramatically restores the mechanical and thermal properties. Overall, the combination of TPF and post-ESL treatment in advanced glassy metals can open a new avenue for ultra-high mechanical and thermal performance micro- and nanomechanical devices for biosensors, MOSFETs and robotics.

Effect of hypothyroidism on the purinergic responses of corpus cavernosal smooth muscle in rabbits

AIMS

Several studies have reported evidence of hormonal abnormalities in 25-35% of impotent men. Hypothyroidism has been reported to occur in 6% of impotent men. In the present study, we examined purinergic relaxation responses in hypothyroidism in an experimental rabbit model and compared them with controls to evaluate the possible involvement of the purinergic pathway.

MATERIALS AND METHODS

The study comprised 20 male New Zealand white rabbits. The rabbits were divided into two equal groups. We tested the effects of ATP, alpha beta ATP, and adenosine precontracted with phenylephrine on the isolated corpus cavernosum preparations from control and hypothyroid rabbits. We also evaluated the effects of ATP, alpha beta ATP, and adenosine on the cGMP levels in the isolated corpus cavernosum preparations from control and hypothyroid rabbits.

RESULTS

T3, T4, and testosterone levels were significantly lower in hypothyroid rabbits. ATP, alpha beta ATP, carbachol, and electrical field stimulation (EFS)-induced frequency-dependent relaxation responses in the isolated rabbit corpus cavernosum strips precontracted with phenylephrine reduced significantly (P<0.05). Adenosine-induced relaxation responses did not change significantly in hypothyroid rabbits.

CONCLUSION

Reduction of relaxation response in hypothyroid rabbits corpus cavernosum can depend on a decreased release of nitric oxide (NO) from nitrergic nerves and endothelium.

The evaluation of the effects of renal failure on erectile dysfunction in a rabbit model of chronic renal failure

OBJECTIVE

To determine whether chronic renal failure (CRF) reduces nitrergic relaxant responses in a rabbit model.

MATERIALS AND METHODS

Ten rabbits underwent surgery to induce uraemia (CRF rabbits) and a further 10 a sham operation (controls). Corpus cavernosal tissue was prepared and used in organ-chamber experiments, with relaxation assessed against a background of pre-contraction with phenylephrine. At the plateau of contraction, relaxation responses to cumulative concentrations of carbachol or sodium nitroprusside (SNP), to test endothelium-dependent and -independent relaxations, respectively, were assessed. Before electrical-field stimulation (EFS), the tissue was treated with an adrenergic nerve blocker and a muscarinic receptor blocker to eliminate the adrenergic and cholinergic components, and to determine the relaxation responses to the stimulation of nonadrenergic, noncholinergic (NANC) nerves. The relaxation responses in corporal strips obtained from CRF rabbits were compared with those from controls.

RESULTS

When tissues were contracted with KCl, tensions were similar in all groups. The impairment in concentration-dependent relaxation with carbachol was significant in CRF rabbits, but SNP- and papaverine-induced concentration-dependent relaxation responses were no different among the groups. EFS-induced frequency-dependent relaxations were significantly lower in CRF rabbits than in controls.

CONCLUSION

CRF inhibits the NANC-mediated relaxation of rabbit corpus cavernosum smooth muscle. Changes in NANC-mediated and carbachol-induced (endothelium-dependent) relaxation of corporal smooth muscle in the rabbit are probably caused by uraemia and subsequently, hyperthyroidism, hyperparathyroidism or low testosterone levels in CRF. These results also suggest that if vasoactive agents are to be used for treating erectile dysfunction in uraemic patients, direct-acting vasodilators and phosphodiesterase inhibitors will be useful.

Effect of chronic renal failure on the purinergic responses of corpus cavernosal smooth muscle in rabbits

OBJECTIVE

To examine purinergic relaxation responses in chronic renal failure (CRF) in an experimental rabbit model, and thus evaluate the possible involvement of the purinergic system in erectile dysfunction with CRF.

MATERIALS AND METHODS

The relaxant effects of ATP were measured in strips of corpus cavernosum smooth muscle taken from control and CRF rabbits. CRF was induced in New Zealand white rabbits as previously described. Penises were excised from CRF rabbits 4 weeks after inducing uraemia. In an organ bath the strips from controls and CRF rabbit corpus cavernosum were pre-contracted with phenylephrine and increasing doses of adenosine and ATP added.

RESULTS

In the pre-contracted rabbit cavernosal tissue the relaxations induced by adenosine and ATP were unchanged in CRF.

CONCLUSION

The lack of any relaxant effect of adenosine or ATP on the relaxation of cavernosal smooth muscle in rabbits with CRF might be because the relaxant effects of these agents are endothelium-independent and the endothelial purinergic receptor density was unchanged in CRF.