PRELIMINARY INSIGHTS IN OXYTOCIN ASSOCIATION WITH THE ONSET OF DIABETIC NEUROPATHY.

Diabetes is one of the most prevalent chronic disorders, associating numerous somatic and behavioral modifications. Oxytocin has been widely studied for its involvement in social behavior and psychiatric disorders. This pilot study presents a series of 3 patients with type 1 diabetes and diabetic neuropathy in which the values of plasma oxytocin, neurotensin, ß-endorphins, α-MSH, substance P and orexin A were measured in comparison to 3 healthy controls with matching ages. In the diabetic patients group, there was a strong negative correlation between the value of plasma glucose and oxytocin (r=-0.99, p=0.04), respectively neurotensin (r=-0.99, p=0.03). These values did not correlate in the control group. The results suggest that oxytocin, in conjunction with neurotensin, could be investigated as a potential early detection marker of diabetic neuropathy and, to our knowledge, this is the first report focusing on plasma oxytocin levels in patients with diabetic neuropathy.

Impact of chronic administration of anabolic androgenic steroids and taurine on blood pressure in rats.

Supraphysiological administration of anabolic androgenic steroids has been linked to increased blood pressure. The widely distributed amino acid taurine seems to be an effective depressor agent in drug-induced hypertension. The purpose of this study was to assess the impact of chronic high dose administration of nandrolone decanoate (DECA) and taurine on blood pressure in rats and to verify the potentially involved mechanisms. The study was conducted in 4 groups of 8 adult male Wistar rats, aged 14 weeks, treated for 12 weeks with: DECA (A group); vehicle (C group); taurine (T group), or with both drugs (AT group). Systolic blood pressure (SBP) was measured at the beginning of the study (SBP1), 2 (SBP2) and 3 months (SBP3) later. Plasma angiotensin-converting enzyme (ACE) activity and plasma end products of nitric oxide metabolism (NOx) were also determined. SBP3 and SBP2 were significantly increased compared to SBP1 only in the A group (P<0.002 for both). SBP2, SBP3 and ACE activity showed a statistically significant increase in the A vs C (P<0.005), andvs AT groups (P<0.05), while NOx was significantly decreased in the A and AT groups vs controls (P=0.01). ACE activity was strongly correlated with SBP3 in the A group (r=0.71, P=0.04). These findings suggest that oral supplementation of taurine may prevent the increase in SBP induced by DECA, an effect potentially mediated by angiotensin-converting enzyme.

Catecholamines reduce transient receptor potential vanilloid type 1 desensitization in cultured dorsal root ganglia neurons.

Sympathetic nervous system and adrenergic receptors are involved in the modulation of dorsal root ganglia neuronal activity, with TRPV1 receptor as an important downstream effector. It is already known that adrenergic sensitization of TRPV1 receptors or catecholamine-induced TRPV1 upregulation are involved in increased excitability and pain via mainly α1 adrenergic receptors, but it is not known if reduced TRPV1 desensitization is involved in this process, as well. Therefore, the aims of this study were to evaluate the effects of epinephrine and norepinephrine on TRPV1 desensitization induced by repeated applications of capsaicin and to assess what would be the involvement of the major α1, α2 and ß adrenergic receptor subtypes. Using calcium microfluorimetry, the effects were evaluated by exposure to 1 µM epinephrine or 10 µM norepinephrine, alone or in the presence of adrenergic receptor inhibitors (phentolamine, prazosin and propranolol) before a 4th capsaicin application in a series of 5 consecutive capsaicin applications. The results showed that both catecholamines produced significant reduction of TRPV1 desensitization, which was mediated by α1, α2 and ß2 receptors. This study completes the general information about TRPV1 sensitization via adrenergic stimulation and may open perspectives for novel pharmacological approaches in skin inflammatory disorders and pain therapy.

THE ROLE OF ESTROGENS AND ESTROGEN RECEPTORS IN MELANOMA DEVELOPMENT AND PROGRESSION.

Melanoma has a significant mortality and its growing incidence is associated with important social and health care costs. Thus, investigation of the complex mechanisms contributing to emergence and development of melanoma are of real interest both in scientific research and clinical practice. Estrogens play an important role in the emergence and development of certain types of cancer, such as breast cancer, endometrial cancer and ovarian cancer, but their role in development of cutaneous melanoma is still a matter of debate. Various data suggest that increased levels of endogenous estrogens during pregnancy or exposure to exogenous estrogens by use of oral contraceptives (OCs) and hormone replacement therapy (HRT) may have a potential role in melanoma development and progression. Moreover, there were revealed several intracellular pathways which can support the connection between estrogens, estrogen receptors (ER) and melanoma. While ER-ß plays an antiproliferative role, ER-α promotes cell growth and cellular atypia. Thus, inhibition of ER-ß activity in the skin can increase the risk for development of cutaneous melanoma and spread of metastatic cells. However, despite recent advances in this area, the exact role and clinical implications of estrogens and estrogen receptors in melanoma are still not entirely understood and require further investigations.

Impact of chronic administration of anabolic androgenic steroids and taurine on blood pressure in rats

Supraphysiological administration of anabolic androgenic steroids has been linked to increased blood pressure. The widely distributed amino acid taurine seems to be an effective depressor agent in drug-induced hypertension. The purpose of this study was to assess the impact of chronic high dose administration of nandrolone decanoate (DECA) and taurine on blood pressure in rats and to verify the potentially involved mechanisms. The study was conducted in 4 groups of 8 adult male Wistar rats, aged 14 weeks, treated for 12 weeks with: DECA (A group); vehicle (C group); taurine (T group), or with both drugs (AT group). Systolic blood pressure (SBP) was measured at the beginning of the study (SBP1), 2 (SBP2) and 3 months (SBP3) later. Plasma angiotensin-converting enzyme (ACE) activity and plasma end products of nitric oxide metabolism (NOx) were also determined. SBP3 and SBP2 were significantly increased compared to SBP1 only in the A group (P<0.002 for both). SBP2, SBP3 and ACE activity showed a statistically significant increase in the A vs C (P<0.005), andvs AT groups (P<0.05), while NOx was significantly decreased in the A and AT groups vs controls (P=0.01). ACE activity was strongly correlated with SBP3 in the A group (r=0.71, P=0.04). These findings suggest that oral supplementation of taurine may prevent the increase in SBP induced by DECA, an effect potentially mediated by angiotensin-converting enzyme.

The role of confocal microscopy in the dermato-oncology practice.

Reflectance-mode confocal microscopy (RCM) is a new in vivo skin imaging technique. We present our one-year experience in RCM examinations in skin tumors and the retrospective analysis of patients enrolled in the Dermatological Department of 'N. Paulescu' Institute using the Fotofinder Dermoscope IIW for the dermatoscopy analysis and VivaScope 1500W for in vivo RCM. We established the rank of RCM in the complex algorithm of skin cancer diagnose, showing that the presented experience can open new possibilities to implement this automated image analyzing system in the routine practice. Our analyzed cases clearly showed that confocal microscopy, therefore, optical biopsy, could guide the clinician towards an accurate diagnosis before surgical removal. Moreover, we emphasized that the development of this technique increases the potential of future teledermatologic applications.